\u7269\u7406\u63a5\u53e3：\u76f4\u63a5\u7ed1\u5b9a\u7f51\u7edc\u8bbe\u5907<\/p>\n<\/li>\n
\u96a7\u9053\u63a5\u53e3（VIFF_TUNNEL）：\u7528\u4e8e\u8de8\u7f51\u7edc\u8f6c\u53d1<\/p>\n<\/li>\n
\u6ce8\u518c\u63a5\u53e3（VIFF_REGISTER）：\u4e0e\u7528\u6237\u6001\u5b88\u62a4\u8fdb\u7a0b\u901a\u4fe1<\/p>\n<\/li>\n<\/ul>\n
3. \u591a\u64ad\u8f6c\u53d1\u7f13\u5b58（struct mfc_cache）<\/h5>\n
struct mfc_cache {
\n struct mfc_common _c;
\n __be32 mfc_origin; \/\/ \u6e90\u5730\u5740
\n __be32 mfc_mcastgrp; \/\/ \u7ec4\u5730\u5740
\n struct mfc_cache_cmp_arg cmparg; \/\/ \u54c8\u5e0c\u6bd4\u8f83\u53c2\u6570
\n};<\/p>\n
\u5173\u952e\u5b57\u6bb5res.ttls[MAXVIFS]\u5b58\u50a8\u6bcf\u4e2a\u51fa\u53e3\u7684TTL\u9608\u503c，\u5b9e\u73b0\u7cbe\u7ec6\u5316\u7684\u51fa\u53e3\u63a7\u5236\u3002<\/p>\n
\n
\u4e8c\u3001\u6570\u636e\u5305\u8f6c\u53d1\u6d41\u7a0b：\u901f\u5ea6\u4e0e\u7cbe\u786e\u7684\u5e73\u8861<\/h4>\n\u8f6c\u53d1\u8def\u5f84（ip_mr_forward）<\/h5>\n
![\"\"](\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2025\/07\/20250729205726-688935b62982b.png\")
<\/p>\n
graph TD
\n A[\u6570\u636e\u5305\u5230\u8fbe] –> B{\u5339\u914dMFC?}
\n B –>|\u662f| C[\u6821\u9a8c\u8f93\u5165\u63a5\u53e3]
\n B –>|\u5426| D[\u52a0\u5165\u672a\u89e3\u6790\u961f\u5217]
\n C –> E[\u904d\u5386\u6240\u6709\u51fa\u53e3]
\n E –> F{TTL\u6709\u6548?}
\n F –>|\u662f| G[\u514b\u9686\u5e76\u53d1\u9001]
\n F –>|\u5426| H[\u8df3\u8fc7\u63a5\u53e3]
\n G –> I[\u66f4\u65b0\u7edf\u8ba1\u4fe1\u606f]<\/p>\n
\u5173\u952e\u4f18\u5316\u70b9：<\/h5>\n
\u5feb\u901f\u514b\u9686\u673a\u5236：\u5bf9\u6bcf\u4e2a\u6709\u6548\u51fa\u53e3\u53ea\u514b\u9686\u5305\u5934，\u907f\u514d\u6570\u636e\u590d\u5236<\/p>\n
if (psend != -1) {
\n struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
\n ipmr_queue_xmit(…, skb2, …);
\n}\n<\/li>\n
\u667a\u80fdTTL\u7ba1\u7406：\u8df3\u8fc7TTL\u4e0d\u8db3\u7684\u63a5\u53e3，\u51cf\u5c11\u65e0\u6548\u64cd\u4f5c<\/p>\n<\/li>\n
\u7edf\u8ba1\u539f\u5b50\u66f4\u65b0：\u65e0\u9501\u66f4\u65b0\u8ba1\u6570\u5668\u786e\u4fdd\u9ad8\u6027\u80fd<\/p>\n<\/li>\n
\n
\u4e09\u3001\u63a7\u5236\u5e73\u9762：\u52a8\u6001\u8def\u7531\u7ba1\u7406<\/h4>\n1. MFC\u751f\u547d\u5468\u671f\u7ba1\u7406<\/h5>\n\n- \n
\u52a8\u6001\u5b66\u4e60：\u901a\u8fc7PIM\/IGMP\u6d88\u606f\u81ea\u52a8\u521b\u5efa\u6761\u76ee<\/p>\n<\/li>\n
- \n
\u9759\u6001\u914d\u7f6e：Netlink\u547d\u4ee4\u624b\u52a8\u6dfb\u52a0<\/p>\n
ip mroute add 192.168.1.100 224.0.0.1 dev eth0\n<\/li>\n
- \n
\u8d85\u65f6\u6e05\u7406：10\u79d2\u672a\u89e3\u6790\u81ea\u52a8\u4e22\u5f03（\u53ef\u914d\u7f6e）<\/p>\n
#define MFC_UNRES_TIMEOUT (10*HZ)\n<\/li>\n<\/ul>\n
2. \u7528\u6237\u6001\u534f\u540c\u673a\u5236<\/h5>\n
\u5185\u6838\u901a\u8fc7\u539f\u59cb\u5957\u63a5\u5b57\u4e0emrouted\/pimd\u4ea4\u4e92：<\/p>\n
static void igmpmsg_netlink_event(struct mr_table *mrt, struct sk_buff *pkt)
\n{
\n \/\/ \u6784\u9020IGMPMSG_NOCACHE\u6d88\u606f
\n \/\/ \u901a\u8fc7NETLINK\u53d1\u9001\u5230\u7528\u6237\u6001
\n}<\/p>\n
\u5b9e\u73b0\u5b9e\u65f6\u8def\u7531\u66f4\u65b0\u548c\u672a\u89e3\u6790\u5305\u901a\u77e5\u3002<\/p>\n
\n\u56db\u3001\u534f\u8bae\u652f\u6301：\u7075\u6d3b\u7684\u5904\u7406\u6846\u67b6<\/h4>\n1. PIM\u534f\u8bae\u5904\u7406<\/h5>\n
\/\/ PIMv2\u5904\u7406\u51fd\u6570
\nstatic int pim_rcv(struct sk_buff *skb)
\n{
\n if (pim->type != ((PIM_VERSION<<4)|PIM_TYPE_REGISTER))
\n goto drop;
\n \/\/ \u9a8c\u8bc1\u6821\u9a8c\u548c
\n \/\/ \u8f6c\u53d1\u5230\u6ce8\u518c\u63a5\u53e3
\n}<\/p>\n
\u652f\u6301PIM-SM\/PIM-DM\u5173\u952e\u7279\u6027，\u5305\u62ec\u6ce8\u518c\u505c\u6b62\u673a\u5236\u3002<\/p>\n
2. IGMP\u4ee3\u7406<\/h5>\n
static int ipmr_cache_report(struct mr_table *mrt,
\n struct sk_buff *pkt, vifi_t vifi, int assert)
\n{
\n \/\/ \u6784\u9020IGMPMSG_WHOLEPKT\u6d88\u606f
\n \/\/ \u53d1\u9001\u5230\u7528\u6237\u6001\u5957\u63a5\u5b57
\n}<\/p>\n
\u5b9e\u73b0\u7ec4\u64ad\u7ec4\u6210\u5458\u5173\u7cfb\u7684\u8de8\u7f51\u7edc\u4f20\u64ad\u3002<\/p>\n
\n\u4e94\u3001\u521b\u65b0\u8bbe\u8ba1：\u6027\u80fd\u4e0e\u6269\u5c55\u6027<\/h4>\n
- \n
\u591a\u8868\u652f\u6301（CONFIG_IP_MROUTE_MULTIPLE_TABLES）<\/p>\n
struct mr_table *ipmr_new_table(struct net *net, u32 id)
\n{
\n \/\/ \u521b\u5efa\u72ec\u7acb\u8def\u7531\u8868
\n}<\/p>\n
\u652f\u6301VRF\u573a\u666f，\u5b9e\u73b0\u7f51\u7edc\u9694\u79bb\u3002<\/p>\n<\/li>\n
- \n
RCU+\u54c8\u5e0c\u8868\u68c0\u7d22<\/p>\n
struct mfc_cache *ipmr_cache_find(struct mr_table *mrt,
\n __be32 origin, __be32 mcastgrp)
\n{
\n \/\/ RCU\u4fdd\u62a4\u7684\u54c8\u5e0c\u67e5\u627e
\n}<\/p>\n
\u5b9e\u73b0\u767e\u4e07\u7ea7\u8def\u7531\u6761\u76ee\u4e0b\u7684\u5fae\u79d2\u7ea7\u68c0\u7d22\u3002<\/p>\n<\/li>\n
- \n
\u52a8\u6001\u5b9a\u65f6\u5668\u7ba1\u7406
\n\u4ec5\u5f53\u5b58\u5728\u672a\u89e3\u6790\u6761\u76ee\u65f6\u6fc0\u6d3b\u5b9a\u65f6\u5668，\u51cf\u5c11\u7a7a\u8f6c\u5f00\u9500\u3002<\/p>\n<\/li>\n
\n\u516d\u3001\u5b9e\u6218\u6d1e\u5bdf：\u5b9a\u4f4d\u591a\u64ad\u95ee\u9898\u7684\u5173\u952e\u70b9<\/h4>\n
- \n
\u67e5\u770b\u8def\u7531\u8868<\/p>\n
cat \/proc\/net\/ip_mr_cache
\n# \u8f93\u51fa\u793a\u4f8b：
\n# Group Origin Iif Pkts Bytes Wrong Oifs
\n# E0000001 C0A80101 2 104 8576 0 1:3<\/p>\n
\u5173\u6ce8"Wrong Oifs"\u8ba1\u6570，\u9ad8\u6570\u503c\u8868\u660e\u63a5\u53e3\u914d\u7f6e\u9519\u8bef\u3002<\/p>\n<\/li>\n
- \n
\u76d1\u63a7\u865a\u62df\u63a5\u53e3<\/p>\n
cat \/proc\/net\/ip_mr_vif
\n# \u8f93\u51fa\u793a\u4f8b：
\n# Interface BytesIn PktsIn BytesOut PktsOut Flags
\n# vif0 15MB 1200 12MB 900 VIFF_TUNNEL<\/p>\n
\u5f02\u5e38\u5b57\u8282\u6570\u6307\u793a\u8def\u7531\u73af\u8def\u6216\u914d\u7f6e\u9519\u8bef\u3002<\/p>\n<\/li>\n
- \n
\u52a8\u6001\u8c03\u8bd5
\n\u542f\u7528\u5185\u6838\u8c03\u8bd5\u9009\u9879：<\/p>\n
echo 1 > \/proc\/sys\/net\/ipv4\/route\/mcast_debug\n<\/li>\n
\n\u7ed3\u8bed<\/h4>\n
Linux\u7684IPv4\u591a\u64ad\u8def\u7531\u901a\u8fc7\u5206\u5c42\u67b6\u6784\u548c\u52a8\u6001\u7ba1\u7406\u673a\u5236，\u5728\u590d\u6742\u7f51\u7edc\u73af\u5883\u4e2d\u5b9e\u73b0\u4e86\u9ad8\u6548\u7a33\u5b9a\u7684\u6570\u636e\u5206\u53d1\u3002\u5176\u6838\u5fc3\u8bbe\u8ba1\u601d\u60f3\u5305\u62ec：<\/p>\n
- \n
\u63a7\u5236\u4e0e\u8f6c\u53d1\u5206\u79bb：\u7528\u6237\u6001\u534f\u8bae\u5904\u7406+\u5185\u6838\u6001\u5feb\u901f\u8f6c\u53d1<\/p>\n<\/li>\n
- \n
\u65f6\u95f4\u7a7a\u95f4\u5e73\u8861：\u54c8\u5e0c\u8868+\u94fe\u8868\u7684\u6df7\u5408\u5b58\u50a8\u7ed3\u6784<\/p>\n<\/li>\n
- \n
\u60f0\u6027\u8ba1\u7b97：\u6309\u9700\u6fc0\u6d3b\u5904\u7406\u6d41\u7a0b<\/p>\n<\/li>\n
\u8fd9\u4e9b\u8bbe\u8ba1\u4f7f\u5f97Linux\u6210\u4e3a\u4ece\u6570\u636e\u4e2d\u5fc3\u5230\u7535\u4fe1\u7f51\u7edc\u7684\u591a\u64ad\u89e3\u51b3\u65b9\u6848\u57fa\u77f3，\u4e3a5G\u7f51\u7edc\u3001IPTV\u7b49\u573a\u666f\u63d0\u4f9b\u4e86\u5173\u952e\u57fa\u7840\u8bbe\u65bd\u652f\u6301\u3002<\/p>\n
![\"\"](\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2025\/07\/20250729205732-688935bcddc50.png\")
<\/p>\n
\/*
\n *IP multicast routing support for mrouted 3.6\/3.8
\n *
\n *(c) 1995 Alan Cox, <alan@lxorguk.ukuu.org.uk>
\n * Linux Consultancy and Custom Driver Development
\n *
\n *This program is free software; you can redistribute it and\/or
\n *modify it under the terms of the GNU General Public License
\n *as published by the Free Software Foundation; either version
\n *2 of the License, or (at your option) any later version.
\n *
\n *Fixes:
\n *Michael Chastain:Incorrect size of copying.
\n *Alan Cox:Added the cache manager code
\n *Alan Cox:Fixed the clone\/copy bug and device race.
\n *Mike McLagan:Routing by source
\n *Malcolm Beattie:Buffer handling fixes.
\n *Alexey Kuznetsov:Double buffer free and other fixes.
\n *SVR Anand:Fixed several multicast bugs and problems.
\n *Alexey Kuznetsov:Status, optimisations and more.
\n *Brad Parker:Better behaviour on mrouted upcall
\n *overflow.
\n * Carlos Picoto : PIMv1 Support
\n *Pavlin Ivanov Radoslavov:PIMv2 Registers must checksum only PIM header
\n *Relax this requirement to work with older peers.
\n *
\n *\/<\/p>\n
#include <linux\/uaccess.h>
\n#include <linux\/types.h>
\n#include <linux\/cache.h>
\n#include <linux\/capability.h>
\n#include <linux\/errno.h>
\n#include <linux\/mm.h>
\n#include <linux\/kernel.h>
\n#include <linux\/fcntl.h>
\n#include <linux\/stat.h>
\n#include <linux\/socket.h>
\n#include <linux\/in.h>
\n#include <linux\/inet.h>
\n#include <linux\/netdevice.h>
\n#include <linux\/inetdevice.h>
\n#include <linux\/igmp.h>
\n#include <linux\/proc_fs.h>
\n#include <linux\/seq_file.h>
\n#include <linux\/mroute.h>
\n#include <linux\/init.h>
\n#include <linux\/if_ether.h>
\n#include <linux\/slab.h>
\n#include <net\/net_namespace.h>
\n#include <net\/ip.h>
\n#include <net\/protocol.h>
\n#include <linux\/skbuff.h>
\n#include <net\/route.h>
\n#include <net\/icmp.h>
\n#include <net\/udp.h>
\n#include <net\/raw.h>
\n#include <linux\/notifier.h>
\n#include <linux\/if_arp.h>
\n#include <linux\/netfilter_ipv4.h>
\n#include <linux\/compat.h>
\n#include <linux\/export.h>
\n#include <linux\/rhashtable.h>
\n#include <net\/ip_tunnels.h>
\n#include <net\/checksum.h>
\n#include <net\/netlink.h>
\n#include <net\/fib_rules.h>
\n#include <linux\/netconf.h>
\n#include <net\/nexthop.h>
\n#include <net\/switchdev.h><\/p>\n
#include <linux\/nospec.h><\/p>\n
struct ipmr_rule {
\nstruct fib_rulecommon;
\n};<\/p>\n
struct ipmr_result {
\nstruct mr_table*mrt;
\n};<\/p>\n
\/* Big lock, protecting vif table, mrt cache and mroute socket state.
\n * Note that the changes are semaphored via rtnl_lock.
\n *\/<\/p>\n
static DEFINE_RWLOCK(mrt_lock);<\/p>\n
\/* Multicast router control variables *\/<\/p>\n
\/* Special spinlock for queue of unresolved entries *\/
\nstatic DEFINE_SPINLOCK(mfc_unres_lock);<\/p>\n
\/* We return to original Alan's scheme. Hash table of resolved
\n * entries is changed only in process context and protected
\n * with weak lock mrt_lock. Queue of unresolved entries is protected
\n * with strong spinlock mfc_unres_lock.
\n *
\n * In this case data path is free of exclusive locks at all.
\n *\/<\/p>\n
static struct kmem_cache *mrt_cachep __ro_after_init;<\/p>\n
static struct mr_table *ipmr_new_table(struct net *net, u32 id);
\nstatic void ipmr_free_table(struct mr_table *mrt);<\/p>\n
static void ip_mr_forward(struct net *net, struct mr_table *mrt,
\n struct net_device *dev, struct sk_buff *skb,
\n struct mfc_cache *cache, int local);
\nstatic int ipmr_cache_report(struct mr_table *mrt,
\n struct sk_buff *pkt, vifi_t vifi, int assert);
\nstatic void mroute_netlink_event(struct mr_table *mrt, struct mfc_cache *mfc,
\n int cmd);
\nstatic void igmpmsg_netlink_event(struct mr_table *mrt, struct sk_buff *pkt);
\nstatic void mroute_clean_tables(struct mr_table *mrt, bool all);
\nstatic void ipmr_expire_process(struct timer_list *t);<\/p>\n
#ifdef CONFIG_IP_MROUTE_MULTIPLE_TABLES
\n#define ipmr_for_each_table(mrt, net) \\\\
\nlist_for_each_entry_rcu(mrt, &net->ipv4.mr_tables, list)<\/p>\n
static struct mr_table *ipmr_mr_table_iter(struct net *net,
\n struct mr_table *mrt)
\n{
\nstruct mr_table *ret;<\/p>\n
if (!mrt)
\nret = list_entry_rcu(net->ipv4.mr_tables.next,
\n struct mr_table, list);
\nelse
\nret = list_entry_rcu(mrt->list.next,
\n struct mr_table, list);<\/p>\n
if (&ret->list == &net->ipv4.mr_tables)
\nreturn NULL;
\nreturn ret;
\n}<\/p>\n
static struct mr_table *ipmr_get_table(struct net *net, u32 id)
\n{
\nstruct mr_table *mrt;<\/p>\n
ipmr_for_each_table(mrt, net) {
\nif (mrt->id == id)
\nreturn mrt;
\n}
\nreturn NULL;
\n}<\/p>\n
static int ipmr_fib_lookup(struct net *net, struct flowi4 *flp4,
\n struct mr_table **mrt)
\n{
\nint err;
\nstruct ipmr_result res;
\nstruct fib_lookup_arg arg = {
\n.result = &res,
\n.flags = FIB_LOOKUP_NOREF,
\n};<\/p>\n
\/* update flow if oif or iif point to device enslaved to l3mdev *\/
\nl3mdev_update_flow(net, flowi4_to_flowi(flp4));<\/p>\n
err = fib_rules_lookup(net->ipv4.mr_rules_ops,
\n flowi4_to_flowi(flp4), 0, &arg);
\nif (err < 0)
\nreturn err;
\n*mrt = res.mrt;
\nreturn 0;
\n}<\/p>\n
static int ipmr_rule_action(struct fib_rule *rule, struct flowi *flp,
\n int flags, struct fib_lookup_arg *arg)
\n{
\nstruct ipmr_result *res = arg->result;
\nstruct mr_table *mrt;<\/p>\n
switch (rule->action) {
\ncase FR_ACT_TO_TBL:
\nbreak;
\ncase FR_ACT_UNREACHABLE:
\nreturn -ENETUNREACH;
\ncase FR_ACT_PROHIBIT:
\nreturn -EACCES;
\ncase FR_ACT_BLACKHOLE:
\ndefault:
\nreturn -EINVAL;
\n}<\/p>\n
arg->table = fib_rule_get_table(rule, arg);<\/p>\n
mrt = ipmr_get_table(rule->fr_net, arg->table);
\nif (!mrt)
\nreturn -EAGAIN;
\nres->mrt = mrt;
\nreturn 0;
\n}<\/p>\n
static int ipmr_rule_match(struct fib_rule *rule, struct flowi *fl, int flags)
\n{
\nreturn 1;
\n}<\/p>\n
static const struct nla_policy ipmr_rule_policy[FRA_MAX + 1] = {
\nFRA_GENERIC_POLICY,
\n};<\/p>\n
static int ipmr_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
\n struct fib_rule_hdr *frh, struct nlattr **tb,
\n struct netlink_ext_ack *extack)
\n{
\nreturn 0;
\n}<\/p>\n
static int ipmr_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
\n struct nlattr **tb)
\n{
\nreturn 1;
\n}<\/p>\n
static int ipmr_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
\n struct fib_rule_hdr *frh)
\n{
\nfrh->dst_len = 0;
\nfrh->src_len = 0;
\nfrh->tos = 0;
\nreturn 0;
\n}<\/p>\n
static const struct fib_rules_ops __net_initconst ipmr_rules_ops_template = {
\n.family= RTNL_FAMILY_IPMR,
\n.rule_size= sizeof(struct ipmr_rule),
\n.addr_size= sizeof(u32),
\n.action= ipmr_rule_action,
\n.match= ipmr_rule_match,
\n.configure= ipmr_rule_configure,
\n.compare= ipmr_rule_compare,
\n.fill= ipmr_rule_fill,
\n.nlgroup= RTNLGRP_IPV4_RULE,
\n.policy= ipmr_rule_policy,
\n.owner= THIS_MODULE,
\n};<\/p>\n
static int __net_init ipmr_rules_init(struct net *net)
\n{
\nstruct fib_rules_ops *ops;
\nstruct mr_table *mrt;
\nint err;<\/p>\n
ops = fib_rules_register(&ipmr_rules_ops_template, net);
\nif (IS_ERR(ops))
\nreturn PTR_ERR(ops);<\/p>\n
INIT_LIST_HEAD(&net->ipv4.mr_tables);<\/p>\n
mrt = ipmr_new_table(net, RT_TABLE_DEFAULT);
\nif (IS_ERR(mrt)) {
\nerr = PTR_ERR(mrt);
\ngoto err1;
\n}<\/p>\n
err = fib_default_rule_add(ops, 0x7fff, RT_TABLE_DEFAULT, 0);
\nif (err < 0)
\ngoto err2;<\/p>\n
net->ipv4.mr_rules_ops = ops;
\nreturn 0;<\/p>\n
err2:
\nipmr_free_table(mrt);
\nerr1:
\nfib_rules_unregister(ops);
\nreturn err;
\n}<\/p>\n
static void __net_exit ipmr_rules_exit(struct net *net)
\n{
\nstruct mr_table *mrt, *next;<\/p>\n
rtnl_lock();
\nlist_for_each_entry_safe(mrt, next, &net->ipv4.mr_tables, list) {
\nlist_del(&mrt->list);
\nipmr_free_table(mrt);
\n}
\nfib_rules_unregister(net->ipv4.mr_rules_ops);
\nrtnl_unlock();
\n}<\/p>\n
static int ipmr_rules_dump(struct net *net, struct notifier_block *nb)
\n{
\nreturn fib_rules_dump(net, nb, RTNL_FAMILY_IPMR);
\n}<\/p>\n
static unsigned int ipmr_rules_seq_read(struct net *net)
\n{
\nreturn fib_rules_seq_read(net, RTNL_FAMILY_IPMR);
\n}<\/p>\n
bool ipmr_rule_default(const struct fib_rule *rule)
\n{
\nreturn fib_rule_matchall(rule) && rule->table == RT_TABLE_DEFAULT;
\n}
\nEXPORT_SYMBOL(ipmr_rule_default);
\n#else
\n#define ipmr_for_each_table(mrt, net) \\\\
\nfor (mrt = net->ipv4.mrt; mrt; mrt = NULL)<\/p>\n
static struct mr_table *ipmr_mr_table_iter(struct net *net,
\n struct mr_table *mrt)
\n{
\nif (!mrt)
\nreturn net->ipv4.mrt;
\nreturn NULL;
\n}<\/p>\n
static struct mr_table *ipmr_get_table(struct net *net, u32 id)
\n{
\nreturn net->ipv4.mrt;
\n}<\/p>\n
static int ipmr_fib_lookup(struct net *net, struct flowi4 *flp4,
\n struct mr_table **mrt)
\n{
\n*mrt = net->ipv4.mrt;
\nreturn 0;
\n}<\/p>\n
static int __net_init ipmr_rules_init(struct net *net)
\n{
\nstruct mr_table *mrt;<\/p>\n
mrt = ipmr_new_table(net, RT_TABLE_DEFAULT);
\nif (IS_ERR(mrt))
\nreturn PTR_ERR(mrt);
\nnet->ipv4.mrt = mrt;
\nreturn 0;
\n}<\/p>\n
static void __net_exit ipmr_rules_exit(struct net *net)
\n{
\nrtnl_lock();
\nipmr_free_table(net->ipv4.mrt);
\nnet->ipv4.mrt = NULL;
\nrtnl_unlock();
\n}<\/p>\n
static int ipmr_rules_dump(struct net *net, struct notifier_block *nb)
\n{
\nreturn 0;
\n}<\/p>\n
static unsigned int ipmr_rules_seq_read(struct net *net)
\n{
\nreturn 0;
\n}<\/p>\n
bool ipmr_rule_default(const struct fib_rule *rule)
\n{
\nreturn true;
\n}
\nEXPORT_SYMBOL(ipmr_rule_default);
\n#endif<\/p>\n
static inline int ipmr_hash_cmp(struct rhashtable_compare_arg *arg,
\nconst void *ptr)
\n{
\nconst struct mfc_cache_cmp_arg *cmparg = arg->key;
\nstruct mfc_cache *c = (struct mfc_cache *)ptr;<\/p>\n
return cmparg->mfc_mcastgrp != c->mfc_mcastgrp ||
\n cmparg->mfc_origin != c->mfc_origin;
\n}<\/p>\n
static const struct rhashtable_params ipmr_rht_params = {
\n.head_offset = offsetof(struct mr_mfc, mnode),
\n.key_offset = offsetof(struct mfc_cache, cmparg),
\n.key_len = sizeof(struct mfc_cache_cmp_arg),
\n.nelem_hint = 3,
\n.locks_mul = 1,
\n.obj_cmpfn = ipmr_hash_cmp,
\n.automatic_shrinking = true,
\n};<\/p>\n
static void ipmr_new_table_set(struct mr_table *mrt,
\n struct net *net)
\n{
\n#ifdef CONFIG_IP_MROUTE_MULTIPLE_TABLES
\nlist_add_tail_rcu(&mrt->list, &net->ipv4.mr_tables);
\n#endif
\n}<\/p>\n
static struct mfc_cache_cmp_arg ipmr_mr_table_ops_cmparg_any = {
\n.mfc_mcastgrp = htonl(INADDR_ANY),
\n.mfc_origin = htonl(INADDR_ANY),
\n};<\/p>\n
static struct mr_table_ops ipmr_mr_table_ops = {
\n.rht_params = &ipmr_rht_params,
\n.cmparg_any = &ipmr_mr_table_ops_cmparg_any,
\n};<\/p>\n
static struct mr_table *ipmr_new_table(struct net *net, u32 id)
\n{
\nstruct mr_table *mrt;<\/p>\n
\/* "pimreg%u" should not exceed 16 bytes (IFNAMSIZ) *\/
\nif (id != RT_TABLE_DEFAULT && id >= 1000000000)
\nreturn ERR_PTR(-EINVAL);<\/p>\n
mrt = ipmr_get_table(net, id);
\nif (mrt)
\nreturn mrt;<\/p>\n
return mr_table_alloc(net, id, &ipmr_mr_table_ops,
\n ipmr_expire_process, ipmr_new_table_set);
\n}<\/p>\n
static void ipmr_free_table(struct mr_table *mrt)
\n{
\ndel_timer_sync(&mrt->ipmr_expire_timer);
\nmroute_clean_tables(mrt, true);
\nrhltable_destroy(&mrt->mfc_hash);
\nkfree(mrt);
\n}<\/p>\n
\/* Service routines creating virtual interfaces: DVMRP tunnels and PIMREG *\/<\/p>\n
static void ipmr_del_tunnel(struct net_device *dev, struct vifctl *v)
\n{
\nstruct net *net = dev_net(dev);<\/p>\n
dev_close(dev);<\/p>\n
dev = __dev_get_by_name(net, "tunl0");
\nif (dev) {
\nconst struct net_device_ops *ops = dev->netdev_ops;
\nstruct ifreq ifr;
\nstruct ip_tunnel_parm p;<\/p>\n
memset(&p, 0, sizeof(p));
\np.iph.daddr = v->vifc_rmt_addr.s_addr;
\np.iph.saddr = v->vifc_lcl_addr.s_addr;
\np.iph.version = 4;
\np.iph.ihl = 5;
\np.iph.protocol = IPPROTO_IPIP;
\nsprintf(p.name, "dvmrp%d", v->vifc_vifi);
\nifr.ifr_ifru.ifru_data = (__force void __user *)&p;<\/p>\n
if (ops->ndo_do_ioctl) {
\nmm_segment_t oldfs = get_fs();<\/p>\n
set_fs(KERNEL_DS);
\nops->ndo_do_ioctl(dev, &ifr, SIOCDELTUNNEL);
\nset_fs(oldfs);
\n}
\n}
\n}<\/p>\n
\/* Initialize ipmr pimreg\/tunnel in_device *\/
\nstatic bool ipmr_init_vif_indev(const struct net_device *dev)
\n{
\nstruct in_device *in_dev;<\/p>\n
ASSERT_RTNL();<\/p>\n
in_dev = __in_dev_get_rtnl(dev);
\nif (!in_dev)
\nreturn false;
\nipv4_devconf_setall(in_dev);
\nneigh_parms_data_state_setall(in_dev->arp_parms);
\nIPV4_DEVCONF(in_dev->cnf, RP_FILTER) = 0;<\/p>\n
return true;
\n}<\/p>\n
static struct net_device *ipmr_new_tunnel(struct net *net, struct vifctl *v)
\n{
\nstruct net_device *dev;<\/p>\n
dev = __dev_get_by_name(net, "tunl0");<\/p>\n
if (dev) {
\nconst struct net_device_ops *ops = dev->netdev_ops;
\nint err;
\nstruct ifreq ifr;
\nstruct ip_tunnel_parm p;<\/p>\n
memset(&p, 0, sizeof(p));
\np.iph.daddr = v->vifc_rmt_addr.s_addr;
\np.iph.saddr = v->vifc_lcl_addr.s_addr;
\np.iph.version = 4;
\np.iph.ihl = 5;
\np.iph.protocol = IPPROTO_IPIP;
\nsprintf(p.name, "dvmrp%d", v->vifc_vifi);
\nifr.ifr_ifru.ifru_data = (__force void __user *)&p;<\/p>\n
if (ops->ndo_do_ioctl) {
\nmm_segment_t oldfs = get_fs();<\/p>\n
set_fs(KERNEL_DS);
\nerr = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
\nset_fs(oldfs);
\n} else {
\nerr = -EOPNOTSUPP;
\n}
\ndev = NULL;<\/p>\n
if (err == 0 &&
\n (dev = __dev_get_by_name(net, p.name)) != NULL) {
\ndev->flags |= IFF_MULTICAST;
\nif (!ipmr_init_vif_indev(dev))
\ngoto failure;
\nif (dev_open(dev))
\ngoto failure;
\ndev_hold(dev);
\n}
\n}
\nreturn dev;<\/p>\n
failure:
\nunregister_netdevice(dev);
\nreturn NULL;
\n}<\/p>\n
#if defined(CONFIG_IP_PIMSM_V1) || defined(CONFIG_IP_PIMSM_V2)
\nstatic netdev_tx_t reg_vif_xmit(struct sk_buff *skb, struct net_device *dev)
\n{
\nstruct net *net = dev_net(dev);
\nstruct mr_table *mrt;
\nstruct flowi4 fl4 = {
\n.flowi4_oif= dev->ifindex,
\n.flowi4_iif= skb->skb_iif ? : LOOPBACK_IFINDEX,
\n.flowi4_mark= skb->mark,
\n};
\nint err;<\/p>\n
err = ipmr_fib_lookup(net, &fl4, &mrt);
\nif (err < 0) {
\nkfree_skb(skb);
\nreturn err;
\n}<\/p>\n
read_lock(&mrt_lock);
\ndev->stats.tx_bytes += skb->len;
\ndev->stats.tx_packets++;
\nipmr_cache_report(mrt, skb, mrt->mroute_reg_vif_num, IGMPMSG_WHOLEPKT);
\nread_unlock(&mrt_lock);
\nkfree_skb(skb);
\nreturn NETDEV_TX_OK;
\n}<\/p>\n
static int reg_vif_get_iflink(const struct net_device *dev)
\n{
\nreturn 0;
\n}<\/p>\n
static const struct net_device_ops reg_vif_netdev_ops = {
\n.ndo_start_xmit= reg_vif_xmit,
\n.ndo_get_iflink = reg_vif_get_iflink,
\n};<\/p>\n
static void reg_vif_setup(struct net_device *dev)
\n{
\ndev->type= ARPHRD_PIMREG;
\ndev->mtu= ETH_DATA_LEN – sizeof(struct iphdr) – 8;
\ndev->flags= IFF_NOARP;
\ndev->netdev_ops= ®_vif_netdev_ops;
\ndev->needs_free_netdev= true;
\ndev->features|= NETIF_F_NETNS_LOCAL;
\n}<\/p>\n
static struct net_device *ipmr_reg_vif(struct net *net, struct mr_table *mrt)
\n{
\nstruct net_device *dev;
\nchar name[IFNAMSIZ];<\/p>\n
if (mrt->id == RT_TABLE_DEFAULT)
\nsprintf(name, "pimreg");
\nelse
\nsprintf(name, "pimreg%u", mrt->id);<\/p>\n
dev = alloc_netdev(0, name, NET_NAME_UNKNOWN, reg_vif_setup);<\/p>\n
if (!dev)
\nreturn NULL;<\/p>\n
dev_net_set(dev, net);<\/p>\n
if (register_netdevice(dev)) {
\nfree_netdev(dev);
\nreturn NULL;
\n}<\/p>\n
if (!ipmr_init_vif_indev(dev))
\ngoto failure;
\nif (dev_open(dev))
\ngoto failure;<\/p>\n
dev_hold(dev);<\/p>\n
return dev;<\/p>\n
failure:
\nunregister_netdevice(dev);
\nreturn NULL;
\n}<\/p>\n
\/* called with rcu_read_lock() *\/
\nstatic int __pim_rcv(struct mr_table *mrt, struct sk_buff *skb,
\n unsigned int pimlen)
\n{
\nstruct net_device *reg_dev = NULL;
\nstruct iphdr *encap;<\/p>\n
encap = (struct iphdr *)(skb_transport_header(skb) + pimlen);
\n\/* Check that:
\n * a. packet is really sent to a multicast group
\n * b. packet is not a NULL-REGISTER
\n * c. packet is not truncated
\n *\/
\nif (!ipv4_is_multicast(encap->daddr) ||
\n encap->tot_len == 0 ||
\n ntohs(encap->tot_len) + pimlen > skb->len)
\nreturn 1;<\/p>\n
read_lock(&mrt_lock);
\nif (mrt->mroute_reg_vif_num >= 0)
\nreg_dev = mrt->vif_table[mrt->mroute_reg_vif_num].dev;
\nread_unlock(&mrt_lock);<\/p>\n
if (!reg_dev)
\nreturn 1;<\/p>\n
skb->mac_header = skb->network_header;
\nskb_pull(skb, (u8 *)encap – skb->data);
\nskb_reset_network_header(skb);
\nskb->protocol = htons(ETH_P_IP);
\nskb->ip_summed = CHECKSUM_NONE;<\/p>\n
skb_tunnel_rx(skb, reg_dev, dev_net(reg_dev));<\/p>\n
netif_rx(skb);<\/p>\n
return NET_RX_SUCCESS;
\n}
\n#else
\nstatic struct net_device *ipmr_reg_vif(struct net *net, struct mr_table *mrt)
\n{
\nreturn NULL;
\n}
\n#endif<\/p>\n
static int call_ipmr_vif_entry_notifiers(struct net *net,
\n enum fib_event_type event_type,
\n struct vif_device *vif,
\n vifi_t vif_index, u32 tb_id)
\n{
\nreturn mr_call_vif_notifiers(net, RTNL_FAMILY_IPMR, event_type,
\n vif, vif_index, tb_id,
\n &net->ipv4.ipmr_seq);
\n}<\/p>\n
static int call_ipmr_mfc_entry_notifiers(struct net *net,
\n enum fib_event_type event_type,
\n struct mfc_cache *mfc, u32 tb_id)
\n{
\nreturn mr_call_mfc_notifiers(net, RTNL_FAMILY_IPMR, event_type,
\n &mfc->_c, tb_id, &net->ipv4.ipmr_seq);
\n}<\/p>\n
\/**
\n *vif_delete – Delete a VIF entry
\n *@notify: Set to 1, if the caller is a notifier_call
\n *\/
\nstatic int vif_delete(struct mr_table *mrt, int vifi, int notify,
\n struct list_head *head)
\n{
\nstruct net *net = read_pnet(&mrt->net);
\nstruct vif_device *v;
\nstruct net_device *dev;
\nstruct in_device *in_dev;<\/p>\n
if (vifi < 0 || vifi >= mrt->maxvif)
\nreturn -EADDRNOTAVAIL;<\/p>\n
v = &mrt->vif_table[vifi];<\/p>\n
if (VIF_EXISTS(mrt, vifi))
\ncall_ipmr_vif_entry_notifiers(net, FIB_EVENT_VIF_DEL, v, vifi,
\n mrt->id);<\/p>\n
write_lock_bh(&mrt_lock);
\ndev = v->dev;
\nv->dev = NULL;<\/p>\n
if (!dev) {
\nwrite_unlock_bh(&mrt_lock);
\nreturn -EADDRNOTAVAIL;
\n}<\/p>\n
if (vifi == mrt->mroute_reg_vif_num)
\nmrt->mroute_reg_vif_num = -1;<\/p>\n
if (vifi + 1 == mrt->maxvif) {
\nint tmp;<\/p>\n
for (tmp = vifi – 1; tmp >= 0; tmp–) {
\nif (VIF_EXISTS(mrt, tmp))
\nbreak;
\n}
\nmrt->maxvif = tmp+1;
\n}<\/p>\n
write_unlock_bh(&mrt_lock);<\/p>\n
dev_set_allmulti(dev, -1);<\/p>\n
in_dev = __in_dev_get_rtnl(dev);
\nif (in_dev) {
\nIPV4_DEVCONF(in_dev->cnf, MC_FORWARDING)–;
\ninet_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
\n NETCONFA_MC_FORWARDING,
\n dev->ifindex, &in_dev->cnf);
\nip_rt_multicast_event(in_dev);
\n}<\/p>\n
if (v->flags & (VIFF_TUNNEL | VIFF_REGISTER) && !notify)
\nunregister_netdevice_queue(dev, head);<\/p>\n
dev_put(dev);
\nreturn 0;
\n}<\/p>\n
static void ipmr_cache_free_rcu(struct rcu_head *head)
\n{
\nstruct mr_mfc *c = container_of(head, struct mr_mfc, rcu);<\/p>\n
kmem_cache_free(mrt_cachep, (struct mfc_cache *)c);
\n}<\/p>\n
static void ipmr_cache_free(struct mfc_cache *c)
\n{
\ncall_rcu(&c->_c.rcu, ipmr_cache_free_rcu);
\n}<\/p>\n
\/* Destroy an unresolved cache entry, killing queued skbs
\n * and reporting error to netlink readers.
\n *\/
\nstatic void ipmr_destroy_unres(struct mr_table *mrt, struct mfc_cache *c)
\n{
\nstruct net *net = read_pnet(&mrt->net);
\nstruct sk_buff *skb;
\nstruct nlmsgerr *e;<\/p>\n
atomic_dec(&mrt->cache_resolve_queue_len);<\/p>\n
while ((skb = skb_dequeue(&c->_c.mfc_un.unres.unresolved))) {
\nif (ip_hdr(skb)->version == 0) {
\nstruct nlmsghdr *nlh = skb_pull(skb,
\nsizeof(struct iphdr));
\nnlh->nlmsg_type = NLMSG_ERROR;
\nnlh->nlmsg_len = nlmsg_msg_size(sizeof(struct nlmsgerr));
\nskb_trim(skb, nlh->nlmsg_len);
\ne = nlmsg_data(nlh);
\ne->error = -ETIMEDOUT;
\nmemset(&e->msg, 0, sizeof(e->msg));<\/p>\n
rtnl_unicast(skb, net, NETLINK_CB(skb).portid);
\n} else {
\nkfree_skb(skb);
\n}
\n}<\/p>\n
ipmr_cache_free(c);
\n}<\/p>\n
\/* Timer process for the unresolved queue. *\/
\nstatic void ipmr_expire_process(struct timer_list *t)
\n{
\nstruct mr_table *mrt = from_timer(mrt, t, ipmr_expire_timer);
\nstruct mr_mfc *c, *next;
\nunsigned long expires;
\nunsigned long now;<\/p>\n
if (!spin_trylock(&mfc_unres_lock)) {
\nmod_timer(&mrt->ipmr_expire_timer, jiffies+HZ\/10);
\nreturn;
\n}<\/p>\n
if (list_empty(&mrt->mfc_unres_queue))
\ngoto out;<\/p>\n
now = jiffies;
\nexpires = 10*HZ;<\/p>\n
list_for_each_entry_safe(c, next, &mrt->mfc_unres_queue, list) {
\nif (time_after(c->mfc_un.unres.expires, now)) {
\nunsigned long interval = c->mfc_un.unres.expires – now;
\nif (interval < expires)
\nexpires = interval;
\ncontinue;
\n}<\/p>\n
list_del(&c->list);
\nmroute_netlink_event(mrt, (struct mfc_cache *)c, RTM_DELROUTE);
\nipmr_destroy_unres(mrt, (struct mfc_cache *)c);
\n}<\/p>\n
if (!list_empty(&mrt->mfc_unres_queue))
\nmod_timer(&mrt->ipmr_expire_timer, jiffies + expires);<\/p>\n
out:
\nspin_unlock(&mfc_unres_lock);
\n}<\/p>\n
\/* Fill oifs list. It is called under write locked mrt_lock. *\/
\nstatic void ipmr_update_thresholds(struct mr_table *mrt, struct mr_mfc *cache,
\n unsigned char *ttls)
\n{
\nint vifi;<\/p>\n
cache->mfc_un.res.minvif = MAXVIFS;
\ncache->mfc_un.res.maxvif = 0;
\nmemset(cache->mfc_un.res.ttls, 255, MAXVIFS);<\/p>\n
for (vifi = 0; vifi < mrt->maxvif; vifi++) {
\nif (VIF_EXISTS(mrt, vifi) &&
\n ttls[vifi] && ttls[vifi] < 255) {
\ncache->mfc_un.res.ttls[vifi] = ttls[vifi];
\nif (cache->mfc_un.res.minvif > vifi)
\ncache->mfc_un.res.minvif = vifi;
\nif (cache->mfc_un.res.maxvif <= vifi)
\ncache->mfc_un.res.maxvif = vifi + 1;
\n}
\n}
\ncache->mfc_un.res.lastuse = jiffies;
\n}<\/p>\n
static int vif_add(struct net *net, struct mr_table *mrt,
\n struct vifctl *vifc, int mrtsock)
\n{
\nint vifi = vifc->vifc_vifi;
\nstruct switchdev_attr attr = {
\n.id = SWITCHDEV_ATTR_ID_PORT_PARENT_ID,
\n};
\nstruct vif_device *v = &mrt->vif_table[vifi];
\nstruct net_device *dev;
\nstruct in_device *in_dev;
\nint err;<\/p>\n
\/* Is vif busy ? *\/
\nif (VIF_EXISTS(mrt, vifi))
\nreturn -EADDRINUSE;<\/p>\n
switch (vifc->vifc_flags) {
\ncase VIFF_REGISTER:
\nif (!ipmr_pimsm_enabled())
\nreturn -EINVAL;
\n\/* Special Purpose VIF in PIM
\n * All the packets will be sent to the daemon
\n *\/
\nif (mrt->mroute_reg_vif_num >= 0)
\nreturn -EADDRINUSE;
\ndev = ipmr_reg_vif(net, mrt);
\nif (!dev)
\nreturn -ENOBUFS;
\nerr = dev_set_allmulti(dev, 1);
\nif (err) {
\nunregister_netdevice(dev);
\ndev_put(dev);
\nreturn err;
\n}
\nbreak;
\ncase VIFF_TUNNEL:
\ndev = ipmr_new_tunnel(net, vifc);
\nif (!dev)
\nreturn -ENOBUFS;
\nerr = dev_set_allmulti(dev, 1);
\nif (err) {
\nipmr_del_tunnel(dev, vifc);
\ndev_put(dev);
\nreturn err;
\n}
\nbreak;
\ncase VIFF_USE_IFINDEX:
\ncase 0:
\nif (vifc->vifc_flags == VIFF_USE_IFINDEX) {
\ndev = dev_get_by_index(net, vifc->vifc_lcl_ifindex);
\nif (dev && !__in_dev_get_rtnl(dev)) {
\ndev_put(dev);
\nreturn -EADDRNOTAVAIL;
\n}
\n} else {
\ndev = ip_dev_find(net, vifc->vifc_lcl_addr.s_addr);
\n}
\nif (!dev)
\nreturn -EADDRNOTAVAIL;
\nerr = dev_set_allmulti(dev, 1);
\nif (err) {
\ndev_put(dev);
\nreturn err;
\n}
\nbreak;
\ndefault:
\nreturn -EINVAL;
\n}<\/p>\n
in_dev = __in_dev_get_rtnl(dev);
\nif (!in_dev) {
\ndev_put(dev);
\nreturn -EADDRNOTAVAIL;
\n}
\nIPV4_DEVCONF(in_dev->cnf, MC_FORWARDING)++;
\ninet_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_MC_FORWARDING,
\n dev->ifindex, &in_dev->cnf);
\nip_rt_multicast_event(in_dev);<\/p>\n
\/* Fill in the VIF structures *\/
\nvif_device_init(v, dev, vifc->vifc_rate_limit,
\nvifc->vifc_threshold,
\nvifc->vifc_flags | (!mrtsock ? VIFF_STATIC : 0),
\n(VIFF_TUNNEL | VIFF_REGISTER));<\/p>\n
attr.orig_dev = dev;
\nif (!switchdev_port_attr_get(dev, &attr)) {
\nmemcpy(v->dev_parent_id.id, attr.u.ppid.id, attr.u.ppid.id_len);
\nv->dev_parent_id.id_len = attr.u.ppid.id_len;
\n} else {
\nv->dev_parent_id.id_len = 0;
\n}<\/p>\n
v->local = vifc->vifc_lcl_addr.s_addr;
\nv->remote = vifc->vifc_rmt_addr.s_addr;<\/p>\n
\/* And finish update writing critical data *\/
\nwrite_lock_bh(&mrt_lock);
\nv->dev = dev;
\nif (v->flags & VIFF_REGISTER)
\nmrt->mroute_reg_vif_num = vifi;
\nif (vifi+1 > mrt->maxvif)
\nmrt->maxvif = vifi+1;
\nwrite_unlock_bh(&mrt_lock);
\ncall_ipmr_vif_entry_notifiers(net, FIB_EVENT_VIF_ADD, v, vifi, mrt->id);
\nreturn 0;
\n}<\/p>\n
\/* called with rcu_read_lock() *\/
\nstatic struct mfc_cache *ipmr_cache_find(struct mr_table *mrt,
\n __be32 origin,
\n __be32 mcastgrp)
\n{
\nstruct mfc_cache_cmp_arg arg = {
\n.mfc_mcastgrp = mcastgrp,
\n.mfc_origin = origin
\n};<\/p>\n
return mr_mfc_find(mrt, &arg);
\n}<\/p>\n
\/* Look for a (*,G) entry *\/
\nstatic struct mfc_cache *ipmr_cache_find_any(struct mr_table *mrt,
\n __be32 mcastgrp, int vifi)
\n{
\nstruct mfc_cache_cmp_arg arg = {
\n.mfc_mcastgrp = mcastgrp,
\n.mfc_origin = htonl(INADDR_ANY)
\n};<\/p>\n
if (mcastgrp == htonl(INADDR_ANY))
\nreturn mr_mfc_find_any_parent(mrt, vifi);
\nreturn mr_mfc_find_any(mrt, vifi, &arg);
\n}<\/p>\n
\/* Look for a (S,G,iif) entry if parent != -1 *\/
\nstatic struct mfc_cache *ipmr_cache_find_parent(struct mr_table *mrt,
\n__be32 origin, __be32 mcastgrp,
\nint parent)
\n{
\nstruct mfc_cache_cmp_arg arg = {
\n.mfc_mcastgrp = mcastgrp,
\n.mfc_origin = origin,
\n};<\/p>\n
return mr_mfc_find_parent(mrt, &arg, parent);
\n}<\/p>\n
\/* Allocate a multicast cache entry *\/
\nstatic struct mfc_cache *ipmr_cache_alloc(void)
\n{
\nstruct mfc_cache *c = kmem_cache_zalloc(mrt_cachep, GFP_KERNEL);<\/p>\n
if (c) {
\nc->_c.mfc_un.res.last_assert = jiffies – MFC_ASSERT_THRESH – 1;
\nc->_c.mfc_un.res.minvif = MAXVIFS;
\nc->_c.free = ipmr_cache_free_rcu;
\nrefcount_set(&c->_c.mfc_un.res.refcount, 1);
\n}
\nreturn c;
\n}<\/p>\n
static struct mfc_cache *ipmr_cache_alloc_unres(void)
\n{
\nstruct mfc_cache *c = kmem_cache_zalloc(mrt_cachep, GFP_ATOMIC);<\/p>\n
if (c) {
\nskb_queue_head_init(&c->_c.mfc_un.unres.unresolved);
\nc->_c.mfc_un.unres.expires = jiffies + 10 * HZ;
\n}
\nreturn c;
\n}<\/p>\n
\/* A cache entry has gone into a resolved state from queued *\/
\nstatic void ipmr_cache_resolve(struct net *net, struct mr_table *mrt,
\n struct mfc_cache *uc, struct mfc_cache *c)
\n{
\nstruct sk_buff *skb;
\nstruct nlmsgerr *e;<\/p>\n
\/* Play the pending entries through our router *\/
\nwhile ((skb = __skb_dequeue(&uc->_c.mfc_un.unres.unresolved))) {
\nif (ip_hdr(skb)->version == 0) {
\nstruct nlmsghdr *nlh = skb_pull(skb,
\nsizeof(struct iphdr));<\/p>\n
if (mr_fill_mroute(mrt, skb, &c->_c,
\n nlmsg_data(nlh)) > 0) {
\nnlh->nlmsg_len = skb_tail_pointer(skb) –
\n (u8 *)nlh;
\n} else {
\nnlh->nlmsg_type = NLMSG_ERROR;
\nnlh->nlmsg_len = nlmsg_msg_size(sizeof(struct nlmsgerr));
\nskb_trim(skb, nlh->nlmsg_len);
\ne = nlmsg_data(nlh);
\ne->error = -EMSGSIZE;
\nmemset(&e->msg, 0, sizeof(e->msg));
\n}<\/p>\n
rtnl_unicast(skb, net, NETLINK_CB(skb).portid);
\n} else {
\nip_mr_forward(net, mrt, skb->dev, skb, c, 0);
\n}
\n}
\n}<\/p>\n
\/* Bounce a cache query up to mrouted and netlink.
\n *
\n * Called under mrt_lock.
\n *\/
\nstatic int ipmr_cache_report(struct mr_table *mrt,
\n struct sk_buff *pkt, vifi_t vifi, int assert)
\n{
\nconst int ihl = ip_hdrlen(pkt);
\nstruct sock *mroute_sk;
\nstruct igmphdr *igmp;
\nstruct igmpmsg *msg;
\nstruct sk_buff *skb;
\nint ret;<\/p>\n
if (assert == IGMPMSG_WHOLEPKT || assert == IGMPMSG_WRVIFWHOLE)
\nskb = skb_realloc_headroom(pkt, sizeof(struct iphdr));
\nelse
\nskb = alloc_skb(128, GFP_ATOMIC);<\/p>\n
if (!skb)
\nreturn -ENOBUFS;<\/p>\n
if (assert == IGMPMSG_WHOLEPKT || assert == IGMPMSG_WRVIFWHOLE) {
\n\/* Ugly, but we have no choice with this interface.
\n * Duplicate old header, fix ihl, length etc.
\n * And all this only to mangle msg->im_msgtype and
\n * to set msg->im_mbz to "mbz" \ud83d\ude42
\n *\/
\nskb_push(skb, sizeof(struct iphdr));
\nskb_reset_network_header(skb);
\nskb_reset_transport_header(skb);
\nmsg = (struct igmpmsg *)skb_network_header(skb);
\nmemcpy(msg, skb_network_header(pkt), sizeof(struct iphdr));
\nmsg->im_msgtype = assert;
\nmsg->im_mbz = 0;
\nif (assert == IGMPMSG_WRVIFWHOLE)
\nmsg->im_vif = vifi;
\nelse
\nmsg->im_vif = mrt->mroute_reg_vif_num;
\nip_hdr(skb)->ihl = sizeof(struct iphdr) >> 2;
\nip_hdr(skb)->tot_len = htons(ntohs(ip_hdr(pkt)->tot_len) +
\n sizeof(struct iphdr));
\n} else {
\n\/* Copy the IP header *\/
\nskb_set_network_header(skb, skb->len);
\nskb_put(skb, ihl);
\nskb_copy_to_linear_data(skb, pkt->data, ihl);
\n\/* Flag to the kernel this is a route add *\/
\nip_hdr(skb)->protocol = 0;
\nmsg = (struct igmpmsg *)skb_network_header(skb);
\nmsg->im_vif = vifi;
\nskb_dst_set(skb, dst_clone(skb_dst(pkt)));
\n\/* Add our header *\/
\nigmp = skb_put(skb, sizeof(struct igmphdr));
\nigmp->type = assert;
\nmsg->im_msgtype = assert;
\nigmp->code = 0;
\nip_hdr(skb)->tot_len = htons(skb->len);\/* Fix the length *\/
\nskb->transport_header = skb->network_header;
\n}<\/p>\n
rcu_read_lock();
\nmroute_sk = rcu_dereference(mrt->mroute_sk);
\nif (!mroute_sk) {
\nrcu_read_unlock();
\nkfree_skb(skb);
\nreturn -EINVAL;
\n}<\/p>\n
igmpmsg_netlink_event(mrt, skb);<\/p>\n
\/* Deliver to mrouted *\/
\nret = sock_queue_rcv_skb(mroute_sk, skb);
\nrcu_read_unlock();
\nif (ret < 0) {
\nnet_warn_ratelimited("mroute: pending queue full, dropping entries\\\\n");
\nkfree_skb(skb);
\n}<\/p>\n
return ret;
\n}<\/p>\n
\/* Queue a packet for resolution. It gets locked cache entry! *\/
\nstatic int ipmr_cache_unresolved(struct mr_table *mrt, vifi_t vifi,
\n struct sk_buff *skb, struct net_device *dev)
\n{
\nconst struct iphdr *iph = ip_hdr(skb);
\nstruct mfc_cache *c;
\nbool found = false;
\nint err;<\/p>\n
spin_lock_bh(&mfc_unres_lock);
\nlist_for_each_entry(c, &mrt->mfc_unres_queue, _c.list) {
\nif (c->mfc_mcastgrp == iph->daddr &&
\n c->mfc_origin == iph->saddr) {
\nfound = true;
\nbreak;
\n}
\n}<\/p>\n
if (!found) {
\n\/* Create a new entry if allowable *\/
\nif (atomic_read(&mrt->cache_resolve_queue_len) >= 10 ||
\n (c = ipmr_cache_alloc_unres()) == NULL) {
\nspin_unlock_bh(&mfc_unres_lock);<\/p>\n
kfree_skb(skb);
\nreturn -ENOBUFS;
\n}<\/p>\n
\/* Fill in the new cache entry *\/
\nc->_c.mfc_parent = -1;
\nc->mfc_origin= iph->saddr;
\nc->mfc_mcastgrp= iph->daddr;<\/p>\n
\/* Reflect first query at mrouted. *\/
\nerr = ipmr_cache_report(mrt, skb, vifi, IGMPMSG_NOCACHE);<\/p>\n
if (err < 0) {
\n\/* If the report failed throw the cache entry
\n out – Brad Parker
\n *\/
\nspin_unlock_bh(&mfc_unres_lock);<\/p>\n
ipmr_cache_free(c);
\nkfree_skb(skb);
\nreturn err;
\n}<\/p>\n
atomic_inc(&mrt->cache_resolve_queue_len);
\nlist_add(&c->_c.list, &mrt->mfc_unres_queue);
\nmroute_netlink_event(mrt, c, RTM_NEWROUTE);<\/p>\n
if (atomic_read(&mrt->cache_resolve_queue_len) == 1)
\nmod_timer(&mrt->ipmr_expire_timer,
\n c->_c.mfc_un.unres.expires);
\n}<\/p>\n
\/* See if we can append the packet *\/
\nif (c->_c.mfc_un.unres.unresolved.qlen > 3) {
\nkfree_skb(skb);
\nerr = -ENOBUFS;
\n} else {
\nif (dev) {
\nskb->dev = dev;
\nskb->skb_iif = dev->ifindex;
\n}
\nskb_queue_tail(&c->_c.mfc_un.unres.unresolved, skb);
\nerr = 0;
\n}<\/p>\n
spin_unlock_bh(&mfc_unres_lock);
\nreturn err;
\n}<\/p>\n
\/* MFC cache manipulation by user space mroute daemon *\/<\/p>\n
static int ipmr_mfc_delete(struct mr_table *mrt, struct mfcctl *mfc, int parent)
\n{
\nstruct net *net = read_pnet(&mrt->net);
\nstruct mfc_cache *c;<\/p>\n
\/* The entries are added\/deleted only under RTNL *\/
\nrcu_read_lock();
\nc = ipmr_cache_find_parent(mrt, mfc->mfcc_origin.s_addr,
\n mfc->mfcc_mcastgrp.s_addr, parent);
\nrcu_read_unlock();
\nif (!c)
\nreturn -ENOENT;
\nrhltable_remove(&mrt->mfc_hash, &c->_c.mnode, ipmr_rht_params);
\nlist_del_rcu(&c->_c.list);
\ncall_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_DEL, c, mrt->id);
\nmroute_netlink_event(mrt, c, RTM_DELROUTE);
\nmr_cache_put(&c->_c);<\/p>\n
return 0;
\n}<\/p>\n
static int ipmr_mfc_add(struct net *net, struct mr_table *mrt,
\nstruct mfcctl *mfc, int mrtsock, int parent)
\n{
\nstruct mfc_cache *uc, *c;
\nstruct mr_mfc *_uc;
\nbool found;
\nint ret;<\/p>\n
if (mfc->mfcc_parent >= MAXVIFS)
\nreturn -ENFILE;<\/p>\n
\/* The entries are added\/deleted only under RTNL *\/
\nrcu_read_lock();
\nc = ipmr_cache_find_parent(mrt, mfc->mfcc_origin.s_addr,
\n mfc->mfcc_mcastgrp.s_addr, parent);
\nrcu_read_unlock();
\nif (c) {
\nwrite_lock_bh(&mrt_lock);
\nc->_c.mfc_parent = mfc->mfcc_parent;
\nipmr_update_thresholds(mrt, &c->_c, mfc->mfcc_ttls);
\nif (!mrtsock)
\nc->_c.mfc_flags |= MFC_STATIC;
\nwrite_unlock_bh(&mrt_lock);
\ncall_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_REPLACE, c,
\n mrt->id);
\nmroute_netlink_event(mrt, c, RTM_NEWROUTE);
\nreturn 0;
\n}<\/p>\n
if (mfc->mfcc_mcastgrp.s_addr != htonl(INADDR_ANY) &&
\n !ipv4_is_multicast(mfc->mfcc_mcastgrp.s_addr))
\nreturn -EINVAL;<\/p>\n
c = ipmr_cache_alloc();
\nif (!c)
\nreturn -ENOMEM;<\/p>\n
c->mfc_origin = mfc->mfcc_origin.s_addr;
\nc->mfc_mcastgrp = mfc->mfcc_mcastgrp.s_addr;
\nc->_c.mfc_parent = mfc->mfcc_parent;
\nipmr_update_thresholds(mrt, &c->_c, mfc->mfcc_ttls);
\nif (!mrtsock)
\nc->_c.mfc_flags |= MFC_STATIC;<\/p>\n
ret = rhltable_insert_key(&mrt->mfc_hash, &c->cmparg, &c->_c.mnode,
\n ipmr_rht_params);
\nif (ret) {
\npr_err("ipmr: rhtable insert error %d\\\\n", ret);
\nipmr_cache_free(c);
\nreturn ret;
\n}
\nlist_add_tail_rcu(&c->_c.list, &mrt->mfc_cache_list);
\n\/* Check to see if we resolved a queued list. If so we
\n * need to send on the frames and tidy up.
\n *\/
\nfound = false;
\nspin_lock_bh(&mfc_unres_lock);
\nlist_for_each_entry(_uc, &mrt->mfc_unres_queue, list) {
\nuc = (struct mfc_cache *)_uc;
\nif (uc->mfc_origin == c->mfc_origin &&
\n uc->mfc_mcastgrp == c->mfc_mcastgrp) {
\nlist_del(&_uc->list);
\natomic_dec(&mrt->cache_resolve_queue_len);
\nfound = true;
\nbreak;
\n}
\n}
\nif (list_empty(&mrt->mfc_unres_queue))
\ndel_timer(&mrt->ipmr_expire_timer);
\nspin_unlock_bh(&mfc_unres_lock);<\/p>\n
if (found) {
\nipmr_cache_resolve(net, mrt, uc, c);
\nipmr_cache_free(uc);
\n}
\ncall_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_ADD, c, mrt->id);
\nmroute_netlink_event(mrt, c, RTM_NEWROUTE);
\nreturn 0;
\n}<\/p>\n
\/* Close the multicast socket, and clear the vif tables etc *\/
\nstatic void mroute_clean_tables(struct mr_table *mrt, bool all)
\n{
\nstruct net *net = read_pnet(&mrt->net);
\nstruct mr_mfc *c, *tmp;
\nstruct mfc_cache *cache;
\nLIST_HEAD(list);
\nint i;<\/p>\n
\/* Shut down all active vif entries *\/
\nfor (i = 0; i < mrt->maxvif; i++) {
\nif (!all && (mrt->vif_table[i].flags & VIFF_STATIC))
\ncontinue;
\nvif_delete(mrt, i, 0, &list);
\n}
\nunregister_netdevice_many(&list);<\/p>\n
\/* Wipe the cache *\/
\nlist_for_each_entry_safe(c, tmp, &mrt->mfc_cache_list, list) {
\nif (!all && (c->mfc_flags & MFC_STATIC))
\ncontinue;
\nrhltable_remove(&mrt->mfc_hash, &c->mnode, ipmr_rht_params);
\nlist_del_rcu(&c->list);
\ncache = (struct mfc_cache *)c;
\ncall_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_DEL, cache,
\n mrt->id);
\nmroute_netlink_event(mrt, cache, RTM_DELROUTE);
\nmr_cache_put(c);
\n}<\/p>\n
if (atomic_read(&mrt->cache_resolve_queue_len) != 0) {
\nspin_lock_bh(&mfc_unres_lock);
\nlist_for_each_entry_safe(c, tmp, &mrt->mfc_unres_queue, list) {
\nlist_del(&c->list);
\ncache = (struct mfc_cache *)c;
\nmroute_netlink_event(mrt, cache, RTM_DELROUTE);
\nipmr_destroy_unres(mrt, cache);
\n}
\nspin_unlock_bh(&mfc_unres_lock);
\n}
\n}<\/p>\n
\/* called from ip_ra_control(), before an RCU grace period,
\n * we dont need to call synchronize_rcu() here
\n *\/
\nstatic void mrtsock_destruct(struct sock *sk)
\n{
\nstruct net *net = sock_net(sk);
\nstruct mr_table *mrt;<\/p>\n
rtnl_lock();
\nipmr_for_each_table(mrt, net) {
\nif (sk == rtnl_dereference(mrt->mroute_sk)) {
\nIPV4_DEVCONF_ALL(net, MC_FORWARDING)–;
\ninet_netconf_notify_devconf(net, RTM_NEWNETCONF,
\n NETCONFA_MC_FORWARDING,
\n NETCONFA_IFINDEX_ALL,
\n net->ipv4.devconf_all);
\nRCU_INIT_POINTER(mrt->mroute_sk, NULL);
\nmroute_clean_tables(mrt, false);
\n}
\n}
\nrtnl_unlock();
\n}<\/p>\n
\/* Socket options and virtual interface manipulation. The whole
\n * virtual interface system is a complete heap, but unfortunately
\n * that's how BSD mrouted happens to think. Maybe one day with a proper
\n * MOSPF\/PIM router set up we can clean this up.
\n *\/<\/p>\n
int ip_mroute_setsockopt(struct sock *sk, int optname, char __user *optval,
\n unsigned int optlen)
\n{
\nstruct net *net = sock_net(sk);
\nint val, ret = 0, parent = 0;
\nstruct mr_table *mrt;
\nstruct vifctl vif;
\nstruct mfcctl mfc;
\nbool do_wrvifwhole;
\nu32 uval;<\/p>\n
\/* There's one exception to the lock – MRT_DONE which needs to unlock *\/
\nrtnl_lock();
\nif (sk->sk_type != SOCK_RAW ||
\n inet_sk(sk)->inet_num != IPPROTO_IGMP) {
\nret = -EOPNOTSUPP;
\ngoto out_unlock;
\n}<\/p>\n
mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
\nif (!mrt) {
\nret = -ENOENT;
\ngoto out_unlock;
\n}
\nif (optname != MRT_INIT) {
\nif (sk != rcu_access_pointer(mrt->mroute_sk) &&
\n !ns_capable(net->user_ns, CAP_NET_ADMIN)) {
\nret = -EACCES;
\ngoto out_unlock;
\n}
\n}<\/p>\n
switch (optname) {
\ncase MRT_INIT:
\nif (optlen != sizeof(int)) {
\nret = -EINVAL;
\nbreak;
\n}
\nif (rtnl_dereference(mrt->mroute_sk)) {
\nret = -EADDRINUSE;
\nbreak;
\n}<\/p>\n
ret = ip_ra_control(sk, 1, mrtsock_destruct);
\nif (ret == 0) {
\nrcu_assign_pointer(mrt->mroute_sk, sk);
\nIPV4_DEVCONF_ALL(net, MC_FORWARDING)++;
\ninet_netconf_notify_devconf(net, RTM_NEWNETCONF,
\n NETCONFA_MC_FORWARDING,
\n NETCONFA_IFINDEX_ALL,
\n net->ipv4.devconf_all);
\n}
\nbreak;
\ncase MRT_DONE:
\nif (sk != rcu_access_pointer(mrt->mroute_sk)) {
\nret = -EACCES;
\n} else {
\n\/* We need to unlock here because mrtsock_destruct takes
\n * care of rtnl itself and we can't change that due to
\n * the IP_ROUTER_ALERT setsockopt which runs without it.
\n *\/
\nrtnl_unlock();
\nret = ip_ra_control(sk, 0, NULL);
\ngoto out;
\n}
\nbreak;
\ncase MRT_ADD_VIF:
\ncase MRT_DEL_VIF:
\nif (optlen != sizeof(vif)) {
\nret = -EINVAL;
\nbreak;
\n}
\nif (copy_from_user(&vif, optval, sizeof(vif))) {
\nret = -EFAULT;
\nbreak;
\n}
\nif (vif.vifc_vifi >= MAXVIFS) {
\nret = -ENFILE;
\nbreak;
\n}
\nif (optname == MRT_ADD_VIF) {
\nret = vif_add(net, mrt, &vif,
\n sk == rtnl_dereference(mrt->mroute_sk));
\n} else {
\nret = vif_delete(mrt, vif.vifc_vifi, 0, NULL);
\n}
\nbreak;
\n\/* Manipulate the forwarding caches. These live
\n * in a sort of kernel\/user symbiosis.
\n *\/
\ncase MRT_ADD_MFC:
\ncase MRT_DEL_MFC:
\nparent = -1;
\n\/* fall through *\/
\ncase MRT_ADD_MFC_PROXY:
\ncase MRT_DEL_MFC_PROXY:
\nif (optlen != sizeof(mfc)) {
\nret = -EINVAL;
\nbreak;
\n}
\nif (copy_from_user(&mfc, optval, sizeof(mfc))) {
\nret = -EFAULT;
\nbreak;
\n}
\nif (parent == 0)
\nparent = mfc.mfcc_parent;
\nif (optname == MRT_DEL_MFC || optname == MRT_DEL_MFC_PROXY)
\nret = ipmr_mfc_delete(mrt, &mfc, parent);
\nelse
\nret = ipmr_mfc_add(net, mrt, &mfc,
\n sk == rtnl_dereference(mrt->mroute_sk),
\n parent);
\nbreak;
\n\/* Control PIM assert. *\/
\ncase MRT_ASSERT:
\nif (optlen != sizeof(val)) {
\nret = -EINVAL;
\nbreak;
\n}
\nif (get_user(val, (int __user *)optval)) {
\nret = -EFAULT;
\nbreak;
\n}
\nmrt->mroute_do_assert = val;
\nbreak;
\ncase MRT_PIM:
\nif (!ipmr_pimsm_enabled()) {
\nret = -ENOPROTOOPT;
\nbreak;
\n}
\nif (optlen != sizeof(val)) {
\nret = -EINVAL;
\nbreak;
\n}
\nif (get_user(val, (int __user *)optval)) {
\nret = -EFAULT;
\nbreak;
\n}<\/p>\n
do_wrvifwhole = (val == IGMPMSG_WRVIFWHOLE);
\nval = !!val;
\nif (val != mrt->mroute_do_pim) {
\nmrt->mroute_do_pim = val;
\nmrt->mroute_do_assert = val;
\nmrt->mroute_do_wrvifwhole = do_wrvifwhole;
\n}
\nbreak;
\ncase MRT_TABLE:
\nif (!IS_BUILTIN(CONFIG_IP_MROUTE_MULTIPLE_TABLES)) {
\nret = -ENOPROTOOPT;
\nbreak;
\n}
\nif (optlen != sizeof(uval)) {
\nret = -EINVAL;
\nbreak;
\n}
\nif (get_user(uval, (u32 __user *)optval)) {
\nret = -EFAULT;
\nbreak;
\n}<\/p>\n
if (sk == rtnl_dereference(mrt->mroute_sk)) {
\nret = -EBUSY;
\n} else {
\nmrt = ipmr_new_table(net, uval);
\nif (IS_ERR(mrt))
\nret = PTR_ERR(mrt);
\nelse
\nraw_sk(sk)->ipmr_table = uval;
\n}
\nbreak;
\n\/* Spurious command, or MRT_VERSION which you cannot set. *\/
\ndefault:
\nret = -ENOPROTOOPT;
\n}
\nout_unlock:
\nrtnl_unlock();
\nout:
\nreturn ret;
\n}<\/p>\n
\/* Getsock opt support for the multicast routing system. *\/
\nint ip_mroute_getsockopt(struct sock *sk, int optname, char __user *optval, int __user *optlen)
\n{
\nint olr;
\nint val;
\nstruct net *net = sock_net(sk);
\nstruct mr_table *mrt;<\/p>\n
if (sk->sk_type != SOCK_RAW ||
\n inet_sk(sk)->inet_num != IPPROTO_IGMP)
\nreturn -EOPNOTSUPP;<\/p>\n
mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
\nif (!mrt)
\nreturn -ENOENT;<\/p>\n
switch (optname) {
\ncase MRT_VERSION:
\nval = 0x0305;
\nbreak;
\ncase MRT_PIM:
\nif (!ipmr_pimsm_enabled())
\nreturn -ENOPROTOOPT;
\nval = mrt->mroute_do_pim;
\nbreak;
\ncase MRT_ASSERT:
\nval = mrt->mroute_do_assert;
\nbreak;
\ndefault:
\nreturn -ENOPROTOOPT;
\n}<\/p>\n
if (get_user(olr, optlen))
\nreturn -EFAULT;
\nolr = min_t(unsigned int, olr, sizeof(int));
\nif (olr < 0)
\nreturn -EINVAL;
\nif (put_user(olr, optlen))
\nreturn -EFAULT;
\nif (copy_to_user(optval, &val, olr))
\nreturn -EFAULT;
\nreturn 0;
\n}<\/p>\n
\/* The IP multicast ioctl support routines. *\/
\nint ipmr_ioctl(struct sock *sk, int cmd, void __user *arg)
\n{
\nstruct sioc_sg_req sr;
\nstruct sioc_vif_req vr;
\nstruct vif_device *vif;
\nstruct mfc_cache *c;
\nstruct net *net = sock_net(sk);
\nstruct mr_table *mrt;<\/p>\n
mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
\nif (!mrt)
\nreturn -ENOENT;<\/p>\n
switch (cmd) {
\ncase SIOCGETVIFCNT:
\nif (copy_from_user(&vr, arg, sizeof(vr)))
\nreturn -EFAULT;
\nif (vr.vifi >= mrt->maxvif)
\nreturn -EINVAL;
\nvr.vifi = array_index_nospec(vr.vifi, mrt->maxvif);
\nread_lock(&mrt_lock);
\nvif = &mrt->vif_table[vr.vifi];
\nif (VIF_EXISTS(mrt, vr.vifi)) {
\nvr.icount = vif->pkt_in;
\nvr.ocount = vif->pkt_out;
\nvr.ibytes = vif->bytes_in;
\nvr.obytes = vif->bytes_out;
\nread_unlock(&mrt_lock);<\/p>\n
if (copy_to_user(arg, &vr, sizeof(vr)))
\nreturn -EFAULT;
\nreturn 0;
\n}
\nread_unlock(&mrt_lock);
\nreturn -EADDRNOTAVAIL;
\ncase SIOCGETSGCNT:
\nif (copy_from_user(&sr, arg, sizeof(sr)))
\nreturn -EFAULT;<\/p>\n
rcu_read_lock();
\nc = ipmr_cache_find(mrt, sr.src.s_addr, sr.grp.s_addr);
\nif (c) {
\nsr.pktcnt = c->_c.mfc_un.res.pkt;
\nsr.bytecnt = c->_c.mfc_un.res.bytes;
\nsr.wrong_if = c->_c.mfc_un.res.wrong_if;
\nrcu_read_unlock();<\/p>\n
if (copy_to_user(arg, &sr, sizeof(sr)))
\nreturn -EFAULT;
\nreturn 0;
\n}
\nrcu_read_unlock();
\nreturn -EADDRNOTAVAIL;
\ndefault:
\nreturn -ENOIOCTLCMD;
\n}
\n}<\/p>\n
#ifdef CONFIG_COMPAT
\nstruct compat_sioc_sg_req {
\nstruct in_addr src;
\nstruct in_addr grp;
\ncompat_ulong_t pktcnt;
\ncompat_ulong_t bytecnt;
\ncompat_ulong_t wrong_if;
\n};<\/p>\n
struct compat_sioc_vif_req {
\nvifi_tvifi;\/* Which iface *\/
\ncompat_ulong_t icount;
\ncompat_ulong_t ocount;
\ncompat_ulong_t ibytes;
\ncompat_ulong_t obytes;
\n};<\/p>\n
int ipmr_compat_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
\n{
\nstruct compat_sioc_sg_req sr;
\nstruct compat_sioc_vif_req vr;
\nstruct vif_device *vif;
\nstruct mfc_cache *c;
\nstruct net *net = sock_net(sk);
\nstruct mr_table *mrt;<\/p>\n
mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
\nif (!mrt)
\nreturn -ENOENT;<\/p>\n
switch (cmd) {
\ncase SIOCGETVIFCNT:
\nif (copy_from_user(&vr, arg, sizeof(vr)))
\nreturn -EFAULT;
\nif (vr.vifi >= mrt->maxvif)
\nreturn -EINVAL;
\nvr.vifi = array_index_nospec(vr.vifi, mrt->maxvif);
\nread_lock(&mrt_lock);
\nvif = &mrt->vif_table[vr.vifi];
\nif (VIF_EXISTS(mrt, vr.vifi)) {
\nvr.icount = vif->pkt_in;
\nvr.ocount = vif->pkt_out;
\nvr.ibytes = vif->bytes_in;
\nvr.obytes = vif->bytes_out;
\nread_unlock(&mrt_lock);<\/p>\n
if (copy_to_user(arg, &vr, sizeof(vr)))
\nreturn -EFAULT;
\nreturn 0;
\n}
\nread_unlock(&mrt_lock);
\nreturn -EADDRNOTAVAIL;
\ncase SIOCGETSGCNT:
\nif (copy_from_user(&sr, arg, sizeof(sr)))
\nreturn -EFAULT;<\/p>\n
rcu_read_lock();
\nc = ipmr_cache_find(mrt, sr.src.s_addr, sr.grp.s_addr);
\nif (c) {
\nsr.pktcnt = c->_c.mfc_un.res.pkt;
\nsr.bytecnt = c->_c.mfc_un.res.bytes;
\nsr.wrong_if = c->_c.mfc_un.res.wrong_if;
\nrcu_read_unlock();<\/p>\n
if (copy_to_user(arg, &sr, sizeof(sr)))
\nreturn -EFAULT;
\nreturn 0;
\n}
\nrcu_read_unlock();
\nreturn -EADDRNOTAVAIL;
\ndefault:
\nreturn -ENOIOCTLCMD;
\n}
\n}
\n#endif<\/p>\n
static int ipmr_device_event(struct notifier_block *this, unsigned long event, void *ptr)
\n{
\nstruct net_device *dev = netdev_notifier_info_to_dev(ptr);
\nstruct net *net = dev_net(dev);
\nstruct mr_table *mrt;
\nstruct vif_device *v;
\nint ct;<\/p>\n
if (event != NETDEV_UNREGISTER)
\nreturn NOTIFY_DONE;<\/p>\n
ipmr_for_each_table(mrt, net) {
\nv = &mrt->vif_table[0];
\nfor (ct = 0; ct < mrt->maxvif; ct++, v++) {
\nif (v->dev == dev)
\nvif_delete(mrt, ct, 1, NULL);
\n}
\n}
\nreturn NOTIFY_DONE;
\n}<\/p>\n
static struct notifier_block ip_mr_notifier = {
\n.notifier_call = ipmr_device_event,
\n};<\/p>\n
\/* Encapsulate a packet by attaching a valid IPIP header to it.
\n * This avoids tunnel drivers and other mess and gives us the speed so
\n * important for multicast video.
\n *\/
\nstatic void ip_encap(struct net *net, struct sk_buff *skb,
\n __be32 saddr, __be32 daddr)
\n{
\nstruct iphdr *iph;
\nconst struct iphdr *old_iph = ip_hdr(skb);<\/p>\n
skb_push(skb, sizeof(struct iphdr));
\nskb->transport_header = skb->network_header;
\nskb_reset_network_header(skb);
\niph = ip_hdr(skb);<\/p>\n
iph->version=4;
\niph->tos=old_iph->tos;
\niph->ttl=old_iph->ttl;
\niph->frag_off=0;
\niph->daddr=daddr;
\niph->saddr=saddr;
\niph->protocol=IPPROTO_IPIP;
\niph->ihl=5;
\niph->tot_len=htons(skb->len);
\nip_select_ident(net, skb, NULL);
\nip_send_check(iph);<\/p>\n
memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
\nnf_reset(skb);
\n}<\/p>\n
static inline int ipmr_forward_finish(struct net *net, struct sock *sk,
\n struct sk_buff *skb)
\n{
\nstruct ip_options *opt = &(IPCB(skb)->opt);<\/p>\n
IP_INC_STATS(net, IPSTATS_MIB_OUTFORWDATAGRAMS);
\nIP_ADD_STATS(net, IPSTATS_MIB_OUTOCTETS, skb->len);<\/p>\n
if (unlikely(opt->optlen))
\nip_forward_options(skb);<\/p>\n
return dst_output(net, sk, skb);
\n}<\/p>\n
#ifdef CONFIG_NET_SWITCHDEV
\nstatic bool ipmr_forward_offloaded(struct sk_buff *skb, struct mr_table *mrt,
\n int in_vifi, int out_vifi)
\n{
\nstruct vif_device *out_vif = &mrt->vif_table[out_vifi];
\nstruct vif_device *in_vif = &mrt->vif_table[in_vifi];<\/p>\n
if (!skb->offload_mr_fwd_mark)
\nreturn false;
\nif (!out_vif->dev_parent_id.id_len || !in_vif->dev_parent_id.id_len)
\nreturn false;
\nreturn netdev_phys_item_id_same(&out_vif->dev_parent_id,
\n&in_vif->dev_parent_id);
\n}
\n#else
\nstatic bool ipmr_forward_offloaded(struct sk_buff *skb, struct mr_table *mrt,
\n int in_vifi, int out_vifi)
\n{
\nreturn false;
\n}
\n#endif<\/p>\n
\/* Processing handlers for ipmr_forward *\/<\/p>\n
static void ipmr_queue_xmit(struct net *net, struct mr_table *mrt,
\n int in_vifi, struct sk_buff *skb,
\n struct mfc_cache *c, int vifi)
\n{
\nconst struct iphdr *iph = ip_hdr(skb);
\nstruct vif_device *vif = &mrt->vif_table[vifi];
\nstruct net_device *dev;
\nstruct rtable *rt;
\nstruct flowi4 fl4;
\nint encap = 0;<\/p>\n
if (!vif->dev)
\ngoto out_free;<\/p>\n
if (vif->flags & VIFF_REGISTER) {
\nvif->pkt_out++;
\nvif->bytes_out += skb->len;
\nvif->dev->stats.tx_bytes += skb->len;
\nvif->dev->stats.tx_packets++;
\nipmr_cache_report(mrt, skb, vifi, IGMPMSG_WHOLEPKT);
\ngoto out_free;
\n}<\/p>\n
if (ipmr_forward_offloaded(skb, mrt, in_vifi, vifi))
\ngoto out_free;<\/p>\n
if (vif->flags & VIFF_TUNNEL) {
\nrt = ip_route_output_ports(net, &fl4, NULL,
\n vif->remote, vif->local,
\n 0, 0,
\n IPPROTO_IPIP,
\n RT_TOS(iph->tos), vif->link);
\nif (IS_ERR(rt))
\ngoto out_free;
\nencap = sizeof(struct iphdr);
\n} else {
\nrt = ip_route_output_ports(net, &fl4, NULL, iph->daddr, 0,
\n 0, 0,
\n IPPROTO_IPIP,
\n RT_TOS(iph->tos), vif->link);
\nif (IS_ERR(rt))
\ngoto out_free;
\n}<\/p>\n
dev = rt->dst.dev;<\/p>\n
if (skb->len+encap > dst_mtu(&rt->dst) && (ntohs(iph->frag_off) & IP_DF)) {
\n\/* Do not fragment multicasts. Alas, IPv4 does not
\n * allow to send ICMP, so that packets will disappear
\n * to blackhole.
\n *\/
\nIP_INC_STATS(net, IPSTATS_MIB_FRAGFAILS);
\nip_rt_put(rt);
\ngoto out_free;
\n}<\/p>\n
encap += LL_RESERVED_SPACE(dev) + rt->dst.header_len;<\/p>\n
if (skb_cow(skb, encap)) {
\nip_rt_put(rt);
\ngoto out_free;
\n}<\/p>\n
vif->pkt_out++;
\nvif->bytes_out += skb->len;<\/p>\n
skb_dst_drop(skb);
\nskb_dst_set(skb, &rt->dst);
\nip_decrease_ttl(ip_hdr(skb));<\/p>\n
\/* FIXME: forward and output firewalls used to be called here.
\n * What do we do with netfilter? — RR
\n *\/
\nif (vif->flags & VIFF_TUNNEL) {
\nip_encap(net, skb, vif->local, vif->remote);
\n\/* FIXME: extra output firewall step used to be here. –RR *\/
\nvif->dev->stats.tx_packets++;
\nvif->dev->stats.tx_bytes += skb->len;
\n}<\/p>\n
IPCB(skb)->flags |= IPSKB_FORWARDED;<\/p>\n
\/* RFC1584 teaches, that DVMRP\/PIM router must deliver packets locally
\n * not only before forwarding, but after forwarding on all output
\n * interfaces. It is clear, if mrouter runs a multicasting
\n * program, it should receive packets not depending to what interface
\n * program is joined.
\n * If we will not make it, the program will have to join on all
\n * interfaces. On the other hand, multihoming host (or router, but
\n * not mrouter) cannot join to more than one interface – it will
\n * result in receiving multiple packets.
\n *\/
\nNF_HOOK(NFPROTO_IPV4, NF_INET_FORWARD,
\nnet, NULL, skb, skb->dev, dev,
\nipmr_forward_finish);
\nreturn;<\/p>\n
out_free:
\nkfree_skb(skb);
\n}<\/p>\n
static int ipmr_find_vif(struct mr_table *mrt, struct net_device *dev)
\n{
\nint ct;<\/p>\n
for (ct = mrt->maxvif-1; ct >= 0; ct–) {
\nif (mrt->vif_table[ct].dev == dev)
\nbreak;
\n}
\nreturn ct;
\n}<\/p>\n
\/* "local" means that we should preserve one skb (for local delivery) *\/
\nstatic void ip_mr_forward(struct net *net, struct mr_table *mrt,
\n struct net_device *dev, struct sk_buff *skb,
\n struct mfc_cache *c, int local)
\n{
\nint true_vifi = ipmr_find_vif(mrt, dev);
\nint psend = -1;
\nint vif, ct;<\/p>\n
vif = c->_c.mfc_parent;
\nc->_c.mfc_un.res.pkt++;
\nc->_c.mfc_un.res.bytes += skb->len;
\nc->_c.mfc_un.res.lastuse = jiffies;<\/p>\n
if (c->mfc_origin == htonl(INADDR_ANY) && true_vifi >= 0) {
\nstruct mfc_cache *cache_proxy;<\/p>\n
\/* For an (*,G) entry, we only check that the incomming
\n * interface is part of the static tree.
\n *\/
\ncache_proxy = mr_mfc_find_any_parent(mrt, vif);
\nif (cache_proxy &&
\n cache_proxy->_c.mfc_un.res.ttls[true_vifi] < 255)
\ngoto forward;
\n}<\/p>\n
\/* Wrong interface: drop packet and (maybe) send PIM assert. *\/
\nif (mrt->vif_table[vif].dev != dev) {
\nif (rt_is_output_route(skb_rtable(skb))) {
\n\/* It is our own packet, looped back.
\n * Very complicated situation…
\n *
\n * The best workaround until routing daemons will be
\n * fixed is not to redistribute packet, if it was
\n * send through wrong interface. It means, that
\n * multicast applications WILL NOT work for
\n * (S,G), which have default multicast route pointing
\n * to wrong oif. In any case, it is not a good
\n * idea to use multicasting applications on router.
\n *\/
\ngoto dont_forward;
\n}<\/p>\n
c->_c.mfc_un.res.wrong_if++;<\/p>\n
if (true_vifi >= 0 && mrt->mroute_do_assert &&
\n \/* pimsm uses asserts, when switching from RPT to SPT,
\n * so that we cannot check that packet arrived on an oif.
\n * It is bad, but otherwise we would need to move pretty
\n * large chunk of pimd to kernel. Ough… –ANK
\n *\/
\n (mrt->mroute_do_pim ||
\n c->_c.mfc_un.res.ttls[true_vifi] < 255) &&
\n time_after(jiffies,
\n c->_c.mfc_un.res.last_assert +
\n MFC_ASSERT_THRESH)) {
\nc->_c.mfc_un.res.last_assert = jiffies;
\nipmr_cache_report(mrt, skb, true_vifi, IGMPMSG_WRONGVIF);
\nif (mrt->mroute_do_wrvifwhole)
\nipmr_cache_report(mrt, skb, true_vifi,
\n IGMPMSG_WRVIFWHOLE);
\n}
\ngoto dont_forward;
\n}<\/p>\n
forward:
\nmrt->vif_table[vif].pkt_in++;
\nmrt->vif_table[vif].bytes_in += skb->len;<\/p>\n
\/* Forward the frame *\/
\nif (c->mfc_origin == htonl(INADDR_ANY) &&
\n c->mfc_mcastgrp == htonl(INADDR_ANY)) {
\nif (true_vifi >= 0 &&
\n true_vifi != c->_c.mfc_parent &&
\n ip_hdr(skb)->ttl >
\nc->_c.mfc_un.res.ttls[c->_c.mfc_parent]) {
\n\/* It's an (*,*) entry and the packet is not coming from
\n * the upstream: forward the packet to the upstream
\n * only.
\n *\/
\npsend = c->_c.mfc_parent;
\ngoto last_forward;
\n}
\ngoto dont_forward;
\n}
\nfor (ct = c->_c.mfc_un.res.maxvif – 1;
\n ct >= c->_c.mfc_un.res.minvif; ct–) {
\n\/* For (*,G) entry, don't forward to the incoming interface *\/
\nif ((c->mfc_origin != htonl(INADDR_ANY) ||
\n ct != true_vifi) &&
\n ip_hdr(skb)->ttl > c->_c.mfc_un.res.ttls[ct]) {
\nif (psend != -1) {
\nstruct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);<\/p>\n
if (skb2)
\nipmr_queue_xmit(net, mrt, true_vifi,
\nskb2, c, psend);
\n}
\npsend = ct;
\n}
\n}
\nlast_forward:
\nif (psend != -1) {
\nif (local) {
\nstruct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);<\/p>\n
if (skb2)
\nipmr_queue_xmit(net, mrt, true_vifi, skb2,
\nc, psend);
\n} else {
\nipmr_queue_xmit(net, mrt, true_vifi, skb, c, psend);
\nreturn;
\n}
\n}<\/p>\n
dont_forward:
\nif (!local)
\nkfree_skb(skb);
\n}<\/p>\n
static struct mr_table *ipmr_rt_fib_lookup(struct net *net, struct sk_buff *skb)
\n{
\nstruct rtable *rt = skb_rtable(skb);
\nstruct iphdr *iph = ip_hdr(skb);
\nstruct flowi4 fl4 = {
\n.daddr = iph->daddr,
\n.saddr = iph->saddr,
\n.flowi4_tos = RT_TOS(iph->tos),
\n.flowi4_oif = (rt_is_output_route(rt) ?
\n skb->dev->ifindex : 0),
\n.flowi4_iif = (rt_is_output_route(rt) ?
\n LOOPBACK_IFINDEX :
\n skb->dev->ifindex),
\n.flowi4_mark = skb->mark,
\n};
\nstruct mr_table *mrt;
\nint err;<\/p>\n
err = ipmr_fib_lookup(net, &fl4, &mrt);
\nif (err)
\nreturn ERR_PTR(err);
\nreturn mrt;
\n}<\/p>\n
\/* Multicast packets for forwarding arrive here
\n * Called with rcu_read_lock();
\n *\/
\nint ip_mr_input(struct sk_buff *skb)
\n{
\nstruct mfc_cache *cache;
\nstruct net *net = dev_net(skb->dev);
\nint local = skb_rtable(skb)->rt_flags & RTCF_LOCAL;
\nstruct mr_table *mrt;
\nstruct net_device *dev;<\/p>\n
\/* skb->dev passed in is the loX master dev for vrfs.
\n * As there are no vifs associated with loopback devices,
\n * get the proper interface that does have a vif associated with it.
\n *\/
\ndev = skb->dev;
\nif (netif_is_l3_master(skb->dev)) {
\ndev = dev_get_by_index_rcu(net, IPCB(skb)->iif);
\nif (!dev) {
\nkfree_skb(skb);
\nreturn -ENODEV;
\n}
\n}<\/p>\n
\/* Packet is looped back after forward, it should not be
\n * forwarded second time, but still can be delivered locally.
\n *\/
\nif (IPCB(skb)->flags & IPSKB_FORWARDED)
\ngoto dont_forward;<\/p>\n
mrt = ipmr_rt_fib_lookup(net, skb);
\nif (IS_ERR(mrt)) {
\nkfree_skb(skb);
\nreturn PTR_ERR(mrt);
\n}
\nif (!local) {
\nif (IPCB(skb)->opt.router_alert) {
\nif (ip_call_ra_chain(skb))
\nreturn 0;
\n} else if (ip_hdr(skb)->protocol == IPPROTO_IGMP) {
\n\/* IGMPv1 (and broken IGMPv2 implementations sort of
\n * Cisco IOS <= 11.2(8)) do not put router alert
\n * option to IGMP packets destined to routable
\n * groups. It is very bad, because it means
\n * that we can forward NO IGMP messages.
\n *\/
\nstruct sock *mroute_sk;<\/p>\n
mroute_sk = rcu_dereference(mrt->mroute_sk);
\nif (mroute_sk) {
\nnf_reset(skb);
\nraw_rcv(mroute_sk, skb);
\nreturn 0;
\n}
\n }
\n}<\/p>\n
\/* already under rcu_read_lock() *\/
\ncache = ipmr_cache_find(mrt, ip_hdr(skb)->saddr, ip_hdr(skb)->daddr);
\nif (!cache) {
\nint vif = ipmr_find_vif(mrt, dev);<\/p>\n
if (vif >= 0)
\ncache = ipmr_cache_find_any(mrt, ip_hdr(skb)->daddr,
\n vif);
\n}<\/p>\n
\/* No usable cache entry *\/
\nif (!cache) {
\nint vif;<\/p>\n
if (local) {
\nstruct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
\nip_local_deliver(skb);
\nif (!skb2)
\nreturn -ENOBUFS;
\nskb = skb2;
\n}<\/p>\n
read_lock(&mrt_lock);
\nvif = ipmr_find_vif(mrt, dev);
\nif (vif >= 0) {
\nint err2 = ipmr_cache_unresolved(mrt, vif, skb, dev);
\nread_unlock(&mrt_lock);<\/p>\n
return err2;
\n}
\nread_unlock(&mrt_lock);
\nkfree_skb(skb);
\nreturn -ENODEV;
\n}<\/p>\n
read_lock(&mrt_lock);
\nip_mr_forward(net, mrt, dev, skb, cache, local);
\nread_unlock(&mrt_lock);<\/p>\n
if (local)
\nreturn ip_local_deliver(skb);<\/p>\n
return 0;<\/p>\n
dont_forward:
\nif (local)
\nreturn ip_local_deliver(skb);
\nkfree_skb(skb);
\nreturn 0;
\n}<\/p>\n
#ifdef CONFIG_IP_PIMSM_V1
\n\/* Handle IGMP messages of PIMv1 *\/
\nint pim_rcv_v1(struct sk_buff *skb)
\n{
\nstruct igmphdr *pim;
\nstruct net *net = dev_net(skb->dev);
\nstruct mr_table *mrt;<\/p>\n
if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(struct iphdr)))
\ngoto drop;<\/p>\n
pim = igmp_hdr(skb);<\/p>\n
mrt = ipmr_rt_fib_lookup(net, skb);
\nif (IS_ERR(mrt))
\ngoto drop;
\nif (!mrt->mroute_do_pim ||
\n pim->group != PIM_V1_VERSION || pim->code != PIM_V1_REGISTER)
\ngoto drop;<\/p>\n
if (__pim_rcv(mrt, skb, sizeof(*pim))) {
\ndrop:
\nkfree_skb(skb);
\n}
\nreturn 0;
\n}
\n#endif<\/p>\n
#ifdef CONFIG_IP_PIMSM_V2
\nstatic int pim_rcv(struct sk_buff *skb)
\n{
\nstruct pimreghdr *pim;
\nstruct net *net = dev_net(skb->dev);
\nstruct mr_table *mrt;<\/p>\n
if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(struct iphdr)))
\ngoto drop;<\/p>\n
pim = (struct pimreghdr *)skb_transport_header(skb);
\nif (pim->type != ((PIM_VERSION << 4) | (PIM_TYPE_REGISTER)) ||
\n (pim->flags & PIM_NULL_REGISTER) ||
\n (ip_compute_csum((void *)pim, sizeof(*pim)) != 0 &&
\n csum_fold(skb_checksum(skb, 0, skb->len, 0))))
\ngoto drop;<\/p>\n
mrt = ipmr_rt_fib_lookup(net, skb);
\nif (IS_ERR(mrt))
\ngoto drop;
\nif (__pim_rcv(mrt, skb, sizeof(*pim))) {
\ndrop:
\nkfree_skb(skb);
\n}
\nreturn 0;
\n}
\n#endif<\/p>\n
int ipmr_get_route(struct net *net, struct sk_buff *skb,
\n __be32 saddr, __be32 daddr,
\n struct rtmsg *rtm, u32 portid)
\n{
\nstruct mfc_cache *cache;
\nstruct mr_table *mrt;
\nint err;<\/p>\n
mrt = ipmr_get_table(net, RT_TABLE_DEFAULT);
\nif (!mrt)
\nreturn -ENOENT;<\/p>\n
rcu_read_lock();
\ncache = ipmr_cache_find(mrt, saddr, daddr);
\nif (!cache && skb->dev) {
\nint vif = ipmr_find_vif(mrt, skb->dev);<\/p>\n
if (vif >= 0)
\ncache = ipmr_cache_find_any(mrt, daddr, vif);
\n}
\nif (!cache) {
\nstruct sk_buff *skb2;
\nstruct iphdr *iph;
\nstruct net_device *dev;
\nint vif = -1;<\/p>\n
dev = skb->dev;
\nread_lock(&mrt_lock);
\nif (dev)
\nvif = ipmr_find_vif(mrt, dev);
\nif (vif < 0) {
\nread_unlock(&mrt_lock);
\nrcu_read_unlock();
\nreturn -ENODEV;
\n}
\nskb2 = skb_clone(skb, GFP_ATOMIC);
\nif (!skb2) {
\nread_unlock(&mrt_lock);
\nrcu_read_unlock();
\nreturn -ENOMEM;
\n}<\/p>\n
NETLINK_CB(skb2).portid = portid;
\nskb_push(skb2, sizeof(struct iphdr));
\nskb_reset_network_header(skb2);
\niph = ip_hdr(skb2);
\niph->ihl = sizeof(struct iphdr) >> 2;
\niph->saddr = saddr;
\niph->daddr = daddr;
\niph->version = 0;
\nerr = ipmr_cache_unresolved(mrt, vif, skb2, dev);
\nread_unlock(&mrt_lock);
\nrcu_read_unlock();
\nreturn err;
\n}<\/p>\n
read_lock(&mrt_lock);
\nerr = mr_fill_mroute(mrt, skb, &cache->_c, rtm);
\nread_unlock(&mrt_lock);
\nrcu_read_unlock();
\nreturn err;
\n}<\/p>\n
static int ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
\n u32 portid, u32 seq, struct mfc_cache *c, int cmd,
\n int flags)
\n{
\nstruct nlmsghdr *nlh;
\nstruct rtmsg *rtm;
\nint err;<\/p>\n
nlh = nlmsg_put(skb, portid, seq, cmd, sizeof(*rtm), flags);
\nif (!nlh)
\nreturn -EMSGSIZE;<\/p>\n
rtm = nlmsg_data(nlh);
\nrtm->rtm_family = RTNL_FAMILY_IPMR;
\nrtm->rtm_dst_len = 32;
\nrtm->rtm_src_len = 32;
\nrtm->rtm_tos = 0;
\nrtm->rtm_table = mrt->id;
\nif (nla_put_u32(skb, RTA_TABLE, mrt->id))
\ngoto nla_put_failure;
\nrtm->rtm_type = RTN_MULTICAST;
\nrtm->rtm_scope = RT_SCOPE_UNIVERSE;
\nif (c->_c.mfc_flags & MFC_STATIC)
\nrtm->rtm_protocol = RTPROT_STATIC;
\nelse
\nrtm->rtm_protocol = RTPROT_MROUTED;
\nrtm->rtm_flags = 0;<\/p>\n
if (nla_put_in_addr(skb, RTA_SRC, c->mfc_origin) ||
\n nla_put_in_addr(skb, RTA_DST, c->mfc_mcastgrp))
\ngoto nla_put_failure;
\nerr = mr_fill_mroute(mrt, skb, &c->_c, rtm);
\n\/* do not break the dump if cache is unresolved *\/
\nif (err < 0 && err != -ENOENT)
\ngoto nla_put_failure;<\/p>\n
nlmsg_end(skb, nlh);
\nreturn 0;<\/p>\n
nla_put_failure:
\nnlmsg_cancel(skb, nlh);
\nreturn -EMSGSIZE;
\n}<\/p>\n
static int _ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
\n u32 portid, u32 seq, struct mr_mfc *c, int cmd,
\n int flags)
\n{
\nreturn ipmr_fill_mroute(mrt, skb, portid, seq, (struct mfc_cache *)c,
\ncmd, flags);
\n}<\/p>\n
static size_t mroute_msgsize(bool unresolved, int maxvif)
\n{
\nsize_t len =
\nNLMSG_ALIGN(sizeof(struct rtmsg))
\n+ nla_total_size(4)\/* RTA_TABLE *\/
\n+ nla_total_size(4)\/* RTA_SRC *\/
\n+ nla_total_size(4)\/* RTA_DST *\/
\n;<\/p>\n
if (!unresolved)
\nlen = len
\n + nla_total_size(4)\/* RTA_IIF *\/
\n + nla_total_size(0)\/* RTA_MULTIPATH *\/
\n + maxvif * NLA_ALIGN(sizeof(struct rtnexthop))
\n\/* RTA_MFC_STATS *\/
\n + nla_total_size_64bit(sizeof(struct rta_mfc_stats))
\n;<\/p>\n
return len;
\n}<\/p>\n
static void mroute_netlink_event(struct mr_table *mrt, struct mfc_cache *mfc,
\n int cmd)
\n{
\nstruct net *net = read_pnet(&mrt->net);
\nstruct sk_buff *skb;
\nint err = -ENOBUFS;<\/p>\n
skb = nlmsg_new(mroute_msgsize(mfc->_c.mfc_parent >= MAXVIFS,
\n mrt->maxvif),
\nGFP_ATOMIC);
\nif (!skb)
\ngoto errout;<\/p>\n
err = ipmr_fill_mroute(mrt, skb, 0, 0, mfc, cmd, 0);
\nif (err < 0)
\ngoto errout;<\/p>\n
rtnl_notify(skb, net, 0, RTNLGRP_IPV4_MROUTE, NULL, GFP_ATOMIC);
\nreturn;<\/p>\n
errout:
\nkfree_skb(skb);
\nif (err < 0)
\nrtnl_set_sk_err(net, RTNLGRP_IPV4_MROUTE, err);
\n}<\/p>\n
static size_t igmpmsg_netlink_msgsize(size_t payloadlen)
\n{
\nsize_t len =
\nNLMSG_ALIGN(sizeof(struct rtgenmsg))
\n+ nla_total_size(1)\/* IPMRA_CREPORT_MSGTYPE *\/
\n+ nla_total_size(4)\/* IPMRA_CREPORT_VIF_ID *\/
\n+ nla_total_size(4)\/* IPMRA_CREPORT_SRC_ADDR *\/
\n+ nla_total_size(4)\/* IPMRA_CREPORT_DST_ADDR *\/
\n\/* IPMRA_CREPORT_PKT *\/
\n+ nla_total_size(payloadlen)
\n;<\/p>\n
return len;
\n}<\/p>\n
static void igmpmsg_netlink_event(struct mr_table *mrt, struct sk_buff *pkt)
\n{
\nstruct net *net = read_pnet(&mrt->net);
\nstruct nlmsghdr *nlh;
\nstruct rtgenmsg *rtgenm;
\nstruct igmpmsg *msg;
\nstruct sk_buff *skb;
\nstruct nlattr *nla;
\nint payloadlen;<\/p>\n
payloadlen = pkt->len – sizeof(struct igmpmsg);
\nmsg = (struct igmpmsg *)skb_network_header(pkt);<\/p>\n
skb = nlmsg_new(igmpmsg_netlink_msgsize(payloadlen), GFP_ATOMIC);
\nif (!skb)
\ngoto errout;<\/p>\n
nlh = nlmsg_put(skb, 0, 0, RTM_NEWCACHEREPORT,
\nsizeof(struct rtgenmsg), 0);
\nif (!nlh)
\ngoto errout;
\nrtgenm = nlmsg_data(nlh);
\nrtgenm->rtgen_family = RTNL_FAMILY_IPMR;
\nif (nla_put_u8(skb, IPMRA_CREPORT_MSGTYPE, msg->im_msgtype) ||
\n nla_put_u32(skb, IPMRA_CREPORT_VIF_ID, msg->im_vif) ||
\n nla_put_in_addr(skb, IPMRA_CREPORT_SRC_ADDR,
\n msg->im_src.s_addr) ||
\n nla_put_in_addr(skb, IPMRA_CREPORT_DST_ADDR,
\n msg->im_dst.s_addr))
\ngoto nla_put_failure;<\/p>\n
nla = nla_reserve(skb, IPMRA_CREPORT_PKT, payloadlen);
\nif (!nla || skb_copy_bits(pkt, sizeof(struct igmpmsg),
\n nla_data(nla), payloadlen))
\ngoto nla_put_failure;<\/p>\n
nlmsg_end(skb, nlh);<\/p>\n
rtnl_notify(skb, net, 0, RTNLGRP_IPV4_MROUTE_R, NULL, GFP_ATOMIC);
\nreturn;<\/p>\n
nla_put_failure:
\nnlmsg_cancel(skb, nlh);
\nerrout:
\nkfree_skb(skb);
\nrtnl_set_sk_err(net, RTNLGRP_IPV4_MROUTE_R, -ENOBUFS);
\n}<\/p>\n
static int ipmr_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh,
\n struct netlink_ext_ack *extack)
\n{
\nstruct net *net = sock_net(in_skb->sk);
\nstruct nlattr *tb[RTA_MAX + 1];
\nstruct sk_buff *skb = NULL;
\nstruct mfc_cache *cache;
\nstruct mr_table *mrt;
\nstruct rtmsg *rtm;
\n__be32 src, grp;
\nu32 tableid;
\nint err;<\/p>\n
err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX,
\n rtm_ipv4_policy, extack);
\nif (err < 0)
\ngoto errout;<\/p>\n
rtm = nlmsg_data(nlh);<\/p>\n
src = tb[RTA_SRC] ? nla_get_in_addr(tb[RTA_SRC]) : 0;
\ngrp = tb[RTA_DST] ? nla_get_in_addr(tb[RTA_DST]) : 0;
\ntableid = tb[RTA_TABLE] ? nla_get_u32(tb[RTA_TABLE]) : 0;<\/p>\n
mrt = ipmr_get_table(net, tableid ? tableid : RT_TABLE_DEFAULT);
\nif (!mrt) {
\nerr = -ENOENT;
\ngoto errout_free;
\n}<\/p>\n
\/* entries are added\/deleted only under RTNL *\/
\nrcu_read_lock();
\ncache = ipmr_cache_find(mrt, src, grp);
\nrcu_read_unlock();
\nif (!cache) {
\nerr = -ENOENT;
\ngoto errout_free;
\n}<\/p>\n
skb = nlmsg_new(mroute_msgsize(false, mrt->maxvif), GFP_KERNEL);
\nif (!skb) {
\nerr = -ENOBUFS;
\ngoto errout_free;
\n}<\/p>\n
err = ipmr_fill_mroute(mrt, skb, NETLINK_CB(in_skb).portid,
\n nlh->nlmsg_seq, cache,
\n RTM_NEWROUTE, 0);
\nif (err < 0)
\ngoto errout_free;<\/p>\n
err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);<\/p>\n
errout:
\nreturn err;<\/p>\n
errout_free:
\nkfree_skb(skb);
\ngoto errout;
\n}<\/p>\n
static int ipmr_rtm_dumproute(struct sk_buff *skb, struct netlink_callback *cb)
\n{
\nreturn mr_rtm_dumproute(skb, cb, ipmr_mr_table_iter,
\n_ipmr_fill_mroute, &mfc_unres_lock);
\n}<\/p>\n
static const struct nla_policy rtm_ipmr_policy[RTA_MAX + 1] = {
\n[RTA_SRC]= { .type = NLA_U32 },
\n[RTA_DST]= { .type = NLA_U32 },
\n[RTA_IIF]= { .type = NLA_U32 },
\n[RTA_TABLE]= { .type = NLA_U32 },
\n[RTA_MULTIPATH]= { .len = sizeof(struct rtnexthop) },
\n};<\/p>\n
static bool ipmr_rtm_validate_proto(unsigned char rtm_protocol)
\n{
\nswitch (rtm_protocol) {
\ncase RTPROT_STATIC:
\ncase RTPROT_MROUTED:
\nreturn true;
\n}
\nreturn false;
\n}<\/p>\n
static int ipmr_nla_get_ttls(const struct nlattr *nla, struct mfcctl *mfcc)
\n{
\nstruct rtnexthop *rtnh = nla_data(nla);
\nint remaining = nla_len(nla), vifi = 0;<\/p>\n
while (rtnh_ok(rtnh, remaining)) {
\nmfcc->mfcc_ttls[vifi] = rtnh->rtnh_hops;
\nif (++vifi == MAXVIFS)
\nbreak;
\nrtnh = rtnh_next(rtnh, &remaining);
\n}<\/p>\n
return remaining > 0 ? -EINVAL : vifi;
\n}<\/p>\n
\/* returns < 0 on error, 0 for ADD_MFC and 1 for ADD_MFC_PROXY *\/
\nstatic int rtm_to_ipmr_mfcc(struct net *net, struct nlmsghdr *nlh,
\n struct mfcctl *mfcc, int *mrtsock,
\n struct mr_table **mrtret,
\n struct netlink_ext_ack *extack)
\n{
\nstruct net_device *dev = NULL;
\nu32 tblid = RT_TABLE_DEFAULT;
\nstruct mr_table *mrt;
\nstruct nlattr *attr;
\nstruct rtmsg *rtm;
\nint ret, rem;<\/p>\n
ret = nlmsg_validate(nlh, sizeof(*rtm), RTA_MAX, rtm_ipmr_policy,
\n extack);
\nif (ret < 0)
\ngoto out;
\nrtm = nlmsg_data(nlh);<\/p>\n
ret = -EINVAL;
\nif (rtm->rtm_family != RTNL_FAMILY_IPMR || rtm->rtm_dst_len != 32 ||
\n rtm->rtm_type != RTN_MULTICAST ||
\n rtm->rtm_scope != RT_SCOPE_UNIVERSE ||
\n !ipmr_rtm_validate_proto(rtm->rtm_protocol))
\ngoto out;<\/p>\n
memset(mfcc, 0, sizeof(*mfcc));
\nmfcc->mfcc_parent = -1;
\nret = 0;
\nnlmsg_for_each_attr(attr, nlh, sizeof(struct rtmsg), rem) {
\nswitch (nla_type(attr)) {
\ncase RTA_SRC:
\nmfcc->mfcc_origin.s_addr = nla_get_be32(attr);
\nbreak;
\ncase RTA_DST:
\nmfcc->mfcc_mcastgrp.s_addr = nla_get_be32(attr);
\nbreak;
\ncase RTA_IIF:
\ndev = __dev_get_by_index(net, nla_get_u32(attr));
\nif (!dev) {
\nret = -ENODEV;
\ngoto out;
\n}
\nbreak;
\ncase RTA_MULTIPATH:
\nif (ipmr_nla_get_ttls(attr, mfcc) < 0) {
\nret = -EINVAL;
\ngoto out;
\n}
\nbreak;
\ncase RTA_PREFSRC:
\nret = 1;
\nbreak;
\ncase RTA_TABLE:
\ntblid = nla_get_u32(attr);
\nbreak;
\n}
\n}
\nmrt = ipmr_get_table(net, tblid);
\nif (!mrt) {
\nret = -ENOENT;
\ngoto out;
\n}
\n*mrtret = mrt;
\n*mrtsock = rtm->rtm_protocol == RTPROT_MROUTED ? 1 : 0;
\nif (dev)
\nmfcc->mfcc_parent = ipmr_find_vif(mrt, dev);<\/p>\n
out:
\nreturn ret;
\n}<\/p>\n
\/* takes care of both newroute and delroute *\/
\nstatic int ipmr_rtm_route(struct sk_buff *skb, struct nlmsghdr *nlh,
\n struct netlink_ext_ack *extack)
\n{
\nstruct net *net = sock_net(skb->sk);
\nint ret, mrtsock, parent;
\nstruct mr_table *tbl;
\nstruct mfcctl mfcc;<\/p>\n
mrtsock = 0;
\ntbl = NULL;
\nret = rtm_to_ipmr_mfcc(net, nlh, &mfcc, &mrtsock, &tbl, extack);
\nif (ret < 0)
\nreturn ret;<\/p>\n
parent = ret ? mfcc.mfcc_parent : -1;
\nif (nlh->nlmsg_type == RTM_NEWROUTE)
\nreturn ipmr_mfc_add(net, tbl, &mfcc, mrtsock, parent);
\nelse
\nreturn ipmr_mfc_delete(tbl, &mfcc, parent);
\n}<\/p>\n
static bool ipmr_fill_table(struct mr_table *mrt, struct sk_buff *skb)
\n{
\nu32 queue_len = atomic_read(&mrt->cache_resolve_queue_len);<\/p>\n
if (nla_put_u32(skb, IPMRA_TABLE_ID, mrt->id) ||
\n nla_put_u32(skb, IPMRA_TABLE_CACHE_RES_QUEUE_LEN, queue_len) ||
\n nla_put_s32(skb, IPMRA_TABLE_MROUTE_REG_VIF_NUM,
\nmrt->mroute_reg_vif_num) ||
\n nla_put_u8(skb, IPMRA_TABLE_MROUTE_DO_ASSERT,
\n mrt->mroute_do_assert) ||
\n nla_put_u8(skb, IPMRA_TABLE_MROUTE_DO_PIM, mrt->mroute_do_pim) ||
\n nla_put_u8(skb, IPMRA_TABLE_MROUTE_DO_WRVIFWHOLE,
\n mrt->mroute_do_wrvifwhole))
\nreturn false;<\/p>\n
return true;
\n}<\/p>\n
static bool ipmr_fill_vif(struct mr_table *mrt, u32 vifid, struct sk_buff *skb)
\n{
\nstruct nlattr *vif_nest;
\nstruct vif_device *vif;<\/p>\n
\/* if the VIF doesn't exist just continue *\/
\nif (!VIF_EXISTS(mrt, vifid))
\nreturn true;<\/p>\n
vif = &mrt->vif_table[vifid];
\nvif_nest = nla_nest_start(skb, IPMRA_VIF);
\nif (!vif_nest)
\nreturn false;
\nif (nla_put_u32(skb, IPMRA_VIFA_IFINDEX, vif->dev->ifindex) ||
\n nla_put_u32(skb, IPMRA_VIFA_VIF_ID, vifid) ||
\n nla_put_u16(skb, IPMRA_VIFA_FLAGS, vif->flags) ||
\n nla_put_u64_64bit(skb, IPMRA_VIFA_BYTES_IN, vif->bytes_in,
\n IPMRA_VIFA_PAD) ||
\n nla_put_u64_64bit(skb, IPMRA_VIFA_BYTES_OUT, vif->bytes_out,
\n IPMRA_VIFA_PAD) ||
\n nla_put_u64_64bit(skb, IPMRA_VIFA_PACKETS_IN, vif->pkt_in,
\n IPMRA_VIFA_PAD) ||
\n nla_put_u64_64bit(skb, IPMRA_VIFA_PACKETS_OUT, vif->pkt_out,
\n IPMRA_VIFA_PAD) ||
\n nla_put_be32(skb, IPMRA_VIFA_LOCAL_ADDR, vif->local) ||
\n nla_put_be32(skb, IPMRA_VIFA_REMOTE_ADDR, vif->remote)) {
\nnla_nest_cancel(skb, vif_nest);
\nreturn false;
\n}
\nnla_nest_end(skb, vif_nest);<\/p>\n
return true;
\n}<\/p>\n
static int ipmr_rtm_dumplink(struct sk_buff *skb, struct netlink_callback *cb)
\n{
\nstruct net *net = sock_net(skb->sk);
\nstruct nlmsghdr *nlh = NULL;
\nunsigned int t = 0, s_t;
\nunsigned int e = 0, s_e;
\nstruct mr_table *mrt;<\/p>\n
s_t = cb->args[0];
\ns_e = cb->args[1];<\/p>\n
ipmr_for_each_table(mrt, net) {
\nstruct nlattr *vifs, *af;
\nstruct ifinfomsg *hdr;
\nu32 i;<\/p>\n
if (t < s_t)
\ngoto skip_table;
\nnlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid,
\ncb->nlh->nlmsg_seq, RTM_NEWLINK,
\nsizeof(*hdr), NLM_F_MULTI);
\nif (!nlh)
\nbreak;<\/p>\n
hdr = nlmsg_data(nlh);
\nmemset(hdr, 0, sizeof(*hdr));
\nhdr->ifi_family = RTNL_FAMILY_IPMR;<\/p>\n
af = nla_nest_start(skb, IFLA_AF_SPEC);
\nif (!af) {
\nnlmsg_cancel(skb, nlh);
\ngoto out;
\n}<\/p>\n
if (!ipmr_fill_table(mrt, skb)) {
\nnlmsg_cancel(skb, nlh);
\ngoto out;
\n}<\/p>\n
vifs = nla_nest_start(skb, IPMRA_TABLE_VIFS);
\nif (!vifs) {
\nnla_nest_end(skb, af);
\nnlmsg_end(skb, nlh);
\ngoto out;
\n}
\nfor (i = 0; i < mrt->maxvif; i++) {
\nif (e < s_e)
\ngoto skip_entry;
\nif (!ipmr_fill_vif(mrt, i, skb)) {
\nnla_nest_end(skb, vifs);
\nnla_nest_end(skb, af);
\nnlmsg_end(skb, nlh);
\ngoto out;
\n}
\nskip_entry:
\ne++;
\n}
\ns_e = 0;
\ne = 0;
\nnla_nest_end(skb, vifs);
\nnla_nest_end(skb, af);
\nnlmsg_end(skb, nlh);
\nskip_table:
\nt++;
\n}<\/p>\n
out:
\ncb->args[1] = e;
\ncb->args[0] = t;<\/p>\n
return skb->len;
\n}<\/p>\n
#ifdef CONFIG_PROC_FS
\n\/* The \/proc interfaces to multicast routing :
\n * \/proc\/net\/ip_mr_cache & \/proc\/net\/ip_mr_vif
\n *\/<\/p>\n
static void *ipmr_vif_seq_start(struct seq_file *seq, loff_t *pos)
\n__acquires(mrt_lock)
\n{
\nstruct mr_vif_iter *iter = seq->private;
\nstruct net *net = seq_file_net(seq);
\nstruct mr_table *mrt;<\/p>\n
mrt = ipmr_get_table(net, RT_TABLE_DEFAULT);
\nif (!mrt)
\nreturn ERR_PTR(-ENOENT);<\/p>\n
iter->mrt = mrt;<\/p>\n
read_lock(&mrt_lock);
\nreturn mr_vif_seq_start(seq, pos);
\n}<\/p>\n
static void ipmr_vif_seq_stop(struct seq_file *seq, void *v)
\n__releases(mrt_lock)
\n{
\nread_unlock(&mrt_lock);
\n}<\/p>\n
static int ipmr_vif_seq_show(struct seq_file *seq, void *v)
\n{
\nstruct mr_vif_iter *iter = seq->private;
\nstruct mr_table *mrt = iter->mrt;<\/p>\n
if (v == SEQ_START_TOKEN) {
\nseq_puts(seq,
\n "Interface BytesIn PktsIn BytesOut PktsOut Flags Local Remote\\\\n");
\n} else {
\nconst struct vif_device *vif = v;
\nconst char *name = vif->dev ?
\n vif->dev->name : "none";<\/p>\n
seq_printf(seq,
\n "%2td %-10s %8ld %7ld %8ld %7ld %05X %08X %08X\\\\n",
\n vif – mrt->vif_table,
\n name, vif->bytes_in, vif->pkt_in,
\n vif->bytes_out, vif->pkt_out,
\n vif->flags, vif->local, vif->remote);
\n}
\nreturn 0;
\n}<\/p>\n
static const struct seq_operations ipmr_vif_seq_ops = {
\n.start = ipmr_vif_seq_start,
\n.next = mr_vif_seq_next,
\n.stop = ipmr_vif_seq_stop,
\n.show = ipmr_vif_seq_show,
\n};<\/p>\n
static void *ipmr_mfc_seq_start(struct seq_file *seq, loff_t *pos)
\n{
\nstruct net *net = seq_file_net(seq);
\nstruct mr_table *mrt;<\/p>\n
mrt = ipmr_get_table(net, RT_TABLE_DEFAULT);
\nif (!mrt)
\nreturn ERR_PTR(-ENOENT);<\/p>\n
return mr_mfc_seq_start(seq, pos, mrt, &mfc_unres_lock);
\n}<\/p>\n
static int ipmr_mfc_seq_show(struct seq_file *seq, void *v)
\n{
\nint n;<\/p>\n
if (v == SEQ_START_TOKEN) {
\nseq_puts(seq,
\n "Group Origin Iif Pkts Bytes Wrong Oifs\\\\n");
\n} else {
\nconst struct mfc_cache *mfc = v;
\nconst struct mr_mfc_iter *it = seq->private;
\nconst struct mr_table *mrt = it->mrt;<\/p>\n
seq_printf(seq, "%08X %08X %-3hd",
\n (__force u32) mfc->mfc_mcastgrp,
\n (__force u32) mfc->mfc_origin,
\n mfc->_c.mfc_parent);<\/p>\n
if (it->cache != &mrt->mfc_unres_queue) {
\nseq_printf(seq, " %8lu %8lu %8lu",
\n mfc->_c.mfc_un.res.pkt,
\n mfc->_c.mfc_un.res.bytes,
\n mfc->_c.mfc_un.res.wrong_if);
\nfor (n = mfc->_c.mfc_un.res.minvif;
\n n < mfc->_c.mfc_un.res.maxvif; n++) {
\nif (VIF_EXISTS(mrt, n) &&
\n mfc->_c.mfc_un.res.ttls[n] < 255)
\nseq_printf(seq,
\n " %2d:%-3d",
\n n, mfc->_c.mfc_un.res.ttls[n]);
\n}
\n} else {
\n\/* unresolved mfc_caches don't contain
\n * pkt, bytes and wrong_if values
\n *\/
\nseq_printf(seq, " %8lu %8lu %8lu", 0ul, 0ul, 0ul);
\n}
\nseq_putc(seq, '\\\\n');
\n}
\nreturn 0;
\n}<\/p>\n
static const struct seq_operations ipmr_mfc_seq_ops = {
\n.start = ipmr_mfc_seq_start,
\n.next = mr_mfc_seq_next,
\n.stop = mr_mfc_seq_stop,
\n.show = ipmr_mfc_seq_show,
\n};
\n#endif<\/p>\n
#ifdef CONFIG_IP_PIMSM_V2
\nstatic const struct net_protocol pim_protocol = {
\n.handler=pim_rcv,
\n.netns_ok=1,
\n};
\n#endif<\/p>\n
static unsigned int ipmr_seq_read(struct net *net)
\n{
\nASSERT_RTNL();<\/p>\n
return net->ipv4.ipmr_seq + ipmr_rules_seq_read(net);
\n}<\/p>\n
static int ipmr_dump(struct net *net, struct notifier_block *nb)
\n{
\nreturn mr_dump(net, nb, RTNL_FAMILY_IPMR, ipmr_rules_dump,
\n ipmr_mr_table_iter, &mrt_lock);
\n}<\/p>\n
static const struct fib_notifier_ops ipmr_notifier_ops_template = {
\n.family= RTNL_FAMILY_IPMR,
\n.fib_seq_read= ipmr_seq_read,
\n.fib_dump= ipmr_dump,
\n.owner= THIS_MODULE,
\n};<\/p>\n
static int __net_init ipmr_notifier_init(struct net *net)
\n{
\nstruct fib_notifier_ops *ops;<\/p>\n
net->ipv4.ipmr_seq = 0;<\/p>\n
ops = fib_notifier_ops_register(&ipmr_notifier_ops_template, net);
\nif (IS_ERR(ops))
\nreturn PTR_ERR(ops);
\nnet->ipv4.ipmr_notifier_ops = ops;<\/p>\n
return 0;
\n}<\/p>\n
static void __net_exit ipmr_notifier_exit(struct net *net)
\n{
\nfib_notifier_ops_unregister(net->ipv4.ipmr_notifier_ops);
\nnet->ipv4.ipmr_notifier_ops = NULL;
\n}<\/p>\n
\/* Setup for IP multicast routing *\/
\nstatic int __net_init ipmr_net_init(struct net *net)
\n{
\nint err;<\/p>\n
err = ipmr_notifier_init(net);
\nif (err)
\ngoto ipmr_notifier_fail;<\/p>\n
err = ipmr_rules_init(net);
\nif (err < 0)
\ngoto ipmr_rules_fail;<\/p>\n
#ifdef CONFIG_PROC_FS
\nerr = -ENOMEM;
\nif (!proc_create_net("ip_mr_vif", 0, net->proc_net, &ipmr_vif_seq_ops,
\nsizeof(struct mr_vif_iter)))
\ngoto proc_vif_fail;
\nif (!proc_create_net("ip_mr_cache", 0, net->proc_net, &ipmr_mfc_seq_ops,
\nsizeof(struct mr_mfc_iter)))
\ngoto proc_cache_fail;
\n#endif
\nreturn 0;<\/p>\n
#ifdef CONFIG_PROC_FS
\nproc_cache_fail:
\nremove_proc_entry("ip_mr_vif", net->proc_net);
\nproc_vif_fail:
\nipmr_rules_exit(net);
\n#endif
\nipmr_rules_fail:
\nipmr_notifier_exit(net);
\nipmr_notifier_fail:
\nreturn err;
\n}<\/p>\n
static void __net_exit ipmr_net_exit(struct net *net)
\n{
\n#ifdef CONFIG_PROC_FS
\nremove_proc_entry("ip_mr_cache", net->proc_net);
\nremove_proc_entry("ip_mr_vif", net->proc_net);
\n#endif
\nipmr_notifier_exit(net);
\nipmr_rules_exit(net);
\n}<\/p>\n
static struct pernet_operations ipmr_net_ops = {
\n.init = ipmr_net_init,
\n.exit = ipmr_net_exit,
\n};<\/p>\n
int __init ip_mr_init(void)
\n{
\nint err;<\/p>\n
mrt_cachep = kmem_cache_create("ip_mrt_cache",
\n sizeof(struct mfc_cache),
\n 0, SLAB_HWCACHE_ALIGN | SLAB_PANIC,
\n NULL);<\/p>\n
err = register_pernet_subsys(&ipmr_net_ops);
\nif (err)
\ngoto reg_pernet_fail;<\/p>\n
err = register_netdevice_notifier(&ip_mr_notifier);
\nif (err)
\ngoto reg_notif_fail;
\n#ifdef CONFIG_IP_PIMSM_V2
\nif (inet_add_protocol(&pim_protocol, IPPROTO_PIM) < 0) {
\npr_err("%s: can't add PIM protocol\\\\n", __func__);
\nerr = -EAGAIN;
\ngoto add_proto_fail;
\n}
\n#endif
\nrtnl_register(RTNL_FAMILY_IPMR, RTM_GETROUTE,
\n ipmr_rtm_getroute, ipmr_rtm_dumproute, 0);
\nrtnl_register(RTNL_FAMILY_IPMR, RTM_NEWROUTE,
\n ipmr_rtm_route, NULL, 0);
\nrtnl_register(RTNL_FAMILY_IPMR, RTM_DELROUTE,
\n ipmr_rtm_route, NULL, 0);<\/p>\n
rtnl_register(RTNL_FAMILY_IPMR, RTM_GETLINK,
\n NULL, ipmr_rtm_dumplink, 0);
\nreturn 0;<\/p>\n
#ifdef CONFIG_IP_PIMSM_V2
\nadd_proto_fail:
\nunregister_netdevice_notifier(&ip_mr_notifier);
\n#endif
\nreg_notif_fail:
\nunregister_pernet_subsys(&ipmr_net_ops);
\nreg_pernet_fail:
\nkmem_cache_destroy(mrt_cachep);
\nreturn err;
\n}<\/p>\n
net\/ipv4\/ipmr.c\u00a0\u662f Linux \u5185\u6838\u4e2d\u5b9e\u73b0 IPv4 \u591a\u64ad\u8def\u7531\u7684\u6838\u5fc3\u6587\u4ef6，\u4e3b\u8981\u652f\u6301\u00a0mrouted\u00a0\u548c PIM（Protocol Independent Multicast）\u534f\u8bae\u3002\u4ee5\u4e0b\u662f\u5bf9\u5176\u5173\u952e\u90e8\u5206\u7684\u8be6\u7ec6\u5206\u6790：<\/p>\n
\n1. \u6838\u5fc3\u6570\u636e\u7ed3\u6784<\/h4>\na) \u591a\u64ad\u8def\u7531\u8868 (struct mr_table)<\/h5>\n
\u7ba1\u7406\u591a\u64ad\u8def\u7531\u4fe1\u606f，\u5305\u542b：<\/p>\n
\n- \n
\u865a\u62df\u63a5\u53e3\u8868 (vif_table): \u5b58\u50a8\u6240\u6709\u865a\u62df\u63a5\u53e3（VIF）\u4fe1\u606f\u3002<\/p>\n<\/li>\n
- \n
\u591a\u64ad\u8f6c\u53d1\u7f13\u5b58 (MFC): \u4f7f\u7528\u54c8\u5e0c\u8868 (mfc_hash) \u5b58\u50a8\u5df2\u89e3\u6790\u7684\u8def\u7531\u6761\u76ee\u3002<\/p>\n<\/li>\n
- \n
\u672a\u89e3\u6790\u961f\u5217 (mfc_unres_queue): \u4e34\u65f6\u5b58\u653e\u5f85\u5904\u7406\u7684\u591a\u64ad\u5305\u3002<\/p>\n<\/li>\n
- \n
\u5b9a\u65f6\u5668 (ipmr_expire_timer): \u6e05\u7406\u8d85\u65f6\u672a\u89e3\u6790\u7684\u6761\u76ee\u3002<\/p>\n<\/li>\n<\/ul>\n
b) \u865a\u62df\u63a5\u53e3 (struct vif_device)<\/h5>\n
\u8868\u793a\u4e00\u4e2a\u591a\u64ad\u865a\u62df\u63a5\u53e3：<\/p>\n
\n- \n
\u8bbe\u5907\u6307\u9488 (dev): \u5173\u8054\u7684\u7f51\u7edc\u8bbe\u5907\u3002<\/p>\n<\/li>\n
- \n
\u672c\u5730\/\u8fdc\u7a0b\u5730\u5740 (local,\u00a0remote): \u96a7\u9053\u7aef\u70b9\u5730\u5740\u3002<\/p>\n<\/li>\n
- \n
\u7edf\u8ba1\u4fe1\u606f: \u6536\u53d1\u5305\u6570\u3001\u5b57\u8282\u6570\u7b49\u3002<\/p>\n<\/li>\n
- \n
\u6807\u5fd7\u4f4d (flags):
\nVIFF_TUNNEL（\u96a7\u9053\u63a5\u53e3）\u3001VIFF_REGISTER（\u6ce8\u518c\u5230\u7528\u6237\u6001）\u3001VIFF_STATIC（\u9759\u6001\u914d\u7f6e）\u3002<\/p>\n<\/li>\n<\/ul>\n
c) \u591a\u64ad\u8f6c\u53d1\u7f13\u5b58 (struct mfc_cache)<\/h5>\n
\u5b58\u50a8\u591a\u64ad\u8def\u7531\u6761\u76ee：<\/p>\n
\n- \n
\u6e90\u5730\u5740\/\u7ec4\u5730\u5740 (mfc_origin,\u00a0mfc_mcastgrp): \u6807\u8bc6\u6d41\u3002<\/p>\n<\/li>\n
- \n
\u8f93\u5165\u63a5\u53e3 (mfc_parent): \u63a5\u6536\u6d41\u91cf\u7684 VIF\u3002<\/p>\n<\/li>\n
- \n
\u8f93\u51fa\u63a5\u53e3 TTL \u6620\u5c04 (res.ttls): \u6bcf\u4e2a VIF \u7684 TTL \u9608\u503c\u3002<\/p>\n<\/li>\n
- \n
\u7edf\u8ba1\u4fe1\u606f: \u8f6c\u53d1\u5305\u6570\u3001\u5b57\u8282\u6570\u3001\u9519\u8bef\u8ba1\u6570\u3002<\/p>\n<\/li>\n<\/ul>\n
\n2. \u6838\u5fc3\u529f\u80fd\u5b9e\u73b0<\/h4>\na) \u865a\u62df\u63a5\u53e3\u7ba1\u7406<\/h5>\n\n- \n
\u521b\u5efa (vif_add)
\n\u652f\u6301\u4e09\u79cd\u7c7b\u578b\u63a5\u53e3：<\/p>\n
\n- \n
VIFF_REGISTER: \u6ce8\u518c\u5230\u7528\u6237\u6001\u5b88\u62a4\u8fdb\u7a0b（\u5982\u00a0pimd）\u3002<\/p>\n<\/li>\n
- \n
VIFF_TUNNEL: \u521b\u5efa IP-in-IP \u96a7\u9053（\u5982 DVMRP）\u3002<\/p>\n<\/li>\n
- \n
\u7269\u7406\u63a5\u53e3: \u7ed1\u5b9a\u5230\u5b9e\u9645\u7f51\u7edc\u8bbe\u5907\u3002<\/p>\n<\/li>\n<\/ul>\n<\/li>\n
- \n
\u5220\u9664 (vif_delete)
\n\u89e3\u9664\u8bbe\u5907\u7ed1\u5b9a，\u66f4\u65b0\u7edf\u8ba1，\u6e05\u7406\u5173\u8054\u8d44\u6e90\u3002<\/p>\n<\/li>\n<\/ul>\n
b) MFC \u6761\u76ee\u7ba1\u7406<\/h5>\n\n- \n
\u52a8\u6001\u5b66\u4e60 (ipmr_cache_find)
\n\u901a\u8fc7\u54c8\u5e0c\u8868\u5feb\u901f\u67e5\u627e MFC \u6761\u76ee\u3002<\/p>\n<\/li>\n
- \n
\u9759\u6001\u914d\u7f6e (ipmr_mfc_add)
\n\u901a\u8fc7 Netlink \u6216 Socket \u6dfb\u52a0\u9759\u6001\u8def\u7531\u3002<\/p>\n<\/li>\n
- \n
\u8d85\u65f6\u5904\u7406 (ipmr_expire_process)
\n\u6e05\u7406\u672a\u89e3\u6790\u7684 MFC \u6761\u76ee（\u9ed8\u8ba4 10 \u79d2\u8d85\u65f6）\u3002<\/p>\n<\/li>\n<\/ul>\n
c) \u6570\u636e\u5305\u8f6c\u53d1 (ip_mr_forward)<\/h5>\n
\u5904\u7406\u6d41\u7a0b：<\/p>\n
- \n
\u67e5\u627e MFC: \u5339\u914d\u6e90\u5730\u5740\u548c\u7ec4\u5730\u5740\u3002<\/p>\n<\/li>\n
- \n
\u9a8c\u8bc1\u8f93\u5165\u63a5\u53e3: \u68c0\u67e5\u5305\u662f\u5426\u4ece\u6b63\u786e VIF \u8fdb\u5165\u3002<\/p>\n<\/li>\n
- \n
TTL \u68c0\u67e5: \u8df3\u8fc7 TTL \u4e0d\u8db3\u7684\u51fa\u53e3\u3002<\/p>\n<\/li>\n
- \n
\u514b\u9686\u5305\u591a\u64ad\u8f6c\u53d1:<\/p>\n
\n- \n
\u96a7\u9053\u63a5\u53e3：\u5c01\u88c5 IP-in-IP \u5934\u3002<\/p>\n<\/li>\n
- \n
\u7269\u7406\u63a5\u53e3：\u76f4\u63a5\u53d1\u9001\u3002<\/p>\n<\/li>\n
- \n
\u6ce8\u518c\u63a5\u53e3：\u63d0\u4ea4\u7ed9\u7528\u6237\u6001\u5b88\u62a4\u8fdb\u7a0b\u3002<\/p>\n<\/li>\n<\/ul>\n<\/li>\n
d) \u672a\u89e3\u6790\u5305\u5904\u7406 (ipmr_cache_unresolved)<\/h5>\n
\u5f53 MFC \u4e0d\u5b58\u5728\u65f6：<\/p>\n
- \n
\u521b\u5efa\u4e34\u65f6 MFC \u6761\u76ee\u5e76\u52a0\u5165\u672a\u89e3\u6790\u961f\u5217\u3002<\/p>\n<\/li>\n
- \n
\u53d1\u9001\u00a0IGMPMSG_NOCACHE\u00a0\u901a\u77e5\u7528\u6237\u6001\u3002<\/p>\n<\/li>\n
- \n
\u6536\u5230\u54cd\u5e94\u540e\u89e3\u6790\u6761\u76ee\u5e76\u8f6c\u53d1\u7f13\u5b58\u7684\u5305\u3002<\/p>\n<\/li>\n
\n3. \u5173\u952e\u534f\u8bae\u652f\u6301<\/h4>\na) PIM \u534f\u8bae\u5904\u7406<\/h5>\n\n- \n
PIMv1 (pim_rcv_v1)
\n\u5904\u7406 PIM \u6ce8\u518c\u6d88\u606f，\u5c01\u88c5\u5305\u8f6c\u53d1\u5230 RP\u3002<\/p>\n<\/li>\n
- \n
PIMv2 (pim_rcv)
\n\u6821\u9a8c\u6d88\u606f\u6709\u6548\u6027，\u8f6c\u53d1\u5230\u6ce8\u518c\u63a5\u53e3\u3002<\/p>\n<\/li>\n<\/ul>\n
b) IGMP \u6d88\u606f<\/h5>\n\n- \n
\u7f13\u5b58\u62a5\u544a (ipmr_cache_report)
\n\u53d1\u9001\u00a0IGMPMSG_WHOLEPKT\u00a0\u901a\u77e5\u7528\u6237\u6001\u65b0\u6d41\u91cf\u3002<\/p>\n<\/li>\n<\/ul>\n
\n4. \u63a7\u5236\u5e73\u9762\u63a5\u53e3<\/h4>\na) Netlink \u64cd\u4f5c<\/h5>\n\n- \n
\u8def\u7531\u64cd\u4f5c (ipmr_rtm_route)
\n\u5904\u7406\u00a0RTM_NEWROUTE\/RTM_DELROUTE\u00a0\u6dfb\u52a0\/\u5220\u9664 MFC\u3002<\/p>\n<\/li>\n
- \n
\u4fe1\u606f\u67e5\u8be2 (ipmr_rtm_dumplink)
\n\u901a\u8fc7\u00a0RTM_GETLINK\u00a0\u8fd4\u56de VIF \u548c MFC \u8868\u4fe1\u606f\u3002<\/p>\n<\/li>\n<\/ul>\n
b) Sysctl \/ Procfs<\/h5>\n\n- \n
\/proc\/net\/ip_mr_vif
\n\u663e\u793a\u6240\u6709 VIF \u7684\u7edf\u8ba1\u4fe1\u606f\u3002<\/p>\n<\/li>\n
- \n
\/proc\/net\/ip_mr_cache
\n\u5217\u51fa MFC \u6761\u76ee，\u5305\u62ec\u6e90\u7ec4\u5730\u5740\u3001\u8f6c\u53d1\u8ba1\u6570\u3002<\/p>\n<\/li>\n<\/ul>\n
c) Socket IOCTL<\/h5>\n\n- \n
SIOCGETVIFCNT
\n\u83b7\u53d6\u6307\u5b9a VIF \u7684\u6d41\u91cf\u7edf\u8ba1\u3002<\/p>\n<\/li>\n
- \n
SIOCGETSGCNT
\n\u67e5\u8be2\u7279\u5b9a\u591a\u64ad\u6d41\u7684\u8f6c\u53d1\u7edf\u8ba1\u3002<\/p>\n<\/li>\n<\/ul>\n
\n5. \u521d\u59cb\u5316\u548c\u6e05\u7406<\/h4>\n\n- \n
\u521d\u59cb\u5316 (ip_mr_init)<\/p>\n
- \n
\u6ce8\u518c\u7f51\u7edc\u5b50\u7cfb\u7edf (register_pernet_subsys)\u3002<\/p>\n<\/li>\n
- \n
\u521b\u5efa MFC \u7f13\u5b58\u5185\u5b58\u6c60 (kmem_cache_create)\u3002<\/p>\n<\/li>\n
- \n
\u6ce8\u518c Netlink \u64cd\u4f5c\u548c PIM \u534f\u8bae\u5904\u7406\u5668\u3002<\/p>\n<\/li>\n
- \n
\u6302\u8f7d Procfs \u6587\u4ef6\u3002<\/p>\n<\/li>\n<\/li>\n
- \n
\u9000\u51fa\u6e05\u7406
\n\u91ca\u653e\u6240\u6709\u8def\u7531\u8868\u3001\u5b9a\u65f6\u5668\u3001Procfs \u9879\u3002<\/p>\n<\/li>\n<\/ul>\n
\n6. \u8bbe\u8ba1\u4eae\u70b9<\/h4>\n\n- \n
\u591a\u8868\u652f\u6301 (CONFIG_IP_MROUTE_MULTIPLE_TABLES)
\n\u5141\u8bb8\u521b\u5efa\u591a\u4e2a\u72ec\u7acb\u7684\u591a\u64ad\u8def\u7531\u8868\u3002<\/p>\n<\/li>\n
- \n
\u9ad8\u6548\u67e5\u627e
\n\u4f7f\u7528 RCU \u4fdd\u62a4\u7684\u54c8\u5e0c\u8868\u7ba1\u7406 MFC\u3002<\/p>\n<\/li>\n
- \n
\u7528\u6237\u6001\u534f\u4f5c
\n\u901a\u8fc7\u539f\u59cb\u5957\u63a5\u5b57 (mroute_sk) \u4e0e\u00a0mrouted\/pimd\u00a0\u4ea4\u4e92\u3002<\/p>\n<\/li>\n
- \n
\u6a21\u5757\u5316\u7ed3\u6784
\n\u5206\u79bb\u8f6c\u53d1\/\u63a7\u5236\u903b\u8f91，\u652f\u6301\u52a8\u6001\u6269\u5c55\u3002<\/p>\n<\/li>\n<\/ul>\n
\n\u603b\u7ed3<\/h4>\n
ipmr.c\u00a0\u5b9e\u73b0\u4e86\u5b8c\u6574\u7684 IPv4 \u591a\u64ad\u8def\u7531\u6846\u67b6，\u6838\u5fc3\u529f\u80fd\u5305\u62ec：<\/p>\n
- \n
\u865a\u62df\u63a5\u53e3\u7ba1\u7406：\u652f\u6301\u7269\u7406\u63a5\u53e3\u3001\u96a7\u9053\u548c\u6ce8\u518c\u63a5\u53e3\u3002<\/p>\n<\/li>\n
- \n
\u8f6c\u53d1\u5f15\u64ce：\u57fa\u4e8e MFC \u6761\u76ee\u9ad8\u6548\u514b\u9686\u8f6c\u53d1\u5305\u3002<\/p>\n<\/li>\n
- \n
\u534f\u8bae\u652f\u6301：\u4e0e PIM\/DVMRP \u5b88\u62a4\u8fdb\u7a0b\u534f\u540c\u5de5\u4f5c\u3002<\/p>\n<\/li>\n
- \n
\u63a7\u5236\u63a5\u53e3：\u63d0\u4f9b Netlink\u3001IOCTL\u3001Procfs \u7b49\u7ba1\u7406\u65b9\u5f0f\u3002
\n\u5176\u8bbe\u8ba1\u5e73\u8861\u4e86\u6027\u80fd\u548c\u7075\u6d3b\u6027，\u662f Linux \u591a\u64ad\u8def\u7531\u7684\u57fa\u77f3\u3002<\/p>\n<\/li>\n","protected":false},"excerpt":{"rendered":"
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\u52a8\u6001\u5b66\u4e60：\u901a\u8fc7PIM\/IGMP\u6d88\u606f\u81ea\u52a8\u521b\u5efa\u6761\u76ee<\/p>\n<\/li>\n
- \n
\u9759\u6001\u914d\u7f6e：Netlink\u547d\u4ee4\u624b\u52a8\u6dfb\u52a0<\/p>\n
ip mroute add 192.168.1.100 224.0.0.1 dev eth0\n<\/li>\n
- \n
\u8d85\u65f6\u6e05\u7406：10\u79d2\u672a\u89e3\u6790\u81ea\u52a8\u4e22\u5f03（\u53ef\u914d\u7f6e）<\/p>\n
#define MFC_UNRES_TIMEOUT (10*HZ)\n<\/li>\n<\/ul>\n
2. \u7528\u6237\u6001\u534f\u540c\u673a\u5236<\/h5>\n
\u5185\u6838\u901a\u8fc7\u539f\u59cb\u5957\u63a5\u5b57\u4e0emrouted\/pimd\u4ea4\u4e92：<\/p>\n
static void igmpmsg_netlink_event(struct mr_table *mrt, struct sk_buff *pkt)
\n{
\n \/\/ \u6784\u9020IGMPMSG_NOCACHE\u6d88\u606f
\n \/\/ \u901a\u8fc7NETLINK\u53d1\u9001\u5230\u7528\u6237\u6001
\n}<\/p>\n\u5b9e\u73b0\u5b9e\u65f6\u8def\u7531\u66f4\u65b0\u548c\u672a\u89e3\u6790\u5305\u901a\u77e5\u3002<\/p>\n
\n\u56db\u3001\u534f\u8bae\u652f\u6301：\u7075\u6d3b\u7684\u5904\u7406\u6846\u67b6<\/h4>\n
1. PIM\u534f\u8bae\u5904\u7406<\/h5>\n
\/\/ PIMv2\u5904\u7406\u51fd\u6570
\nstatic int pim_rcv(struct sk_buff *skb)
\n{
\n if (pim->type != ((PIM_VERSION<<4)|PIM_TYPE_REGISTER))
\n goto drop;
\n \/\/ \u9a8c\u8bc1\u6821\u9a8c\u548c
\n \/\/ \u8f6c\u53d1\u5230\u6ce8\u518c\u63a5\u53e3
\n}<\/p>\n\u652f\u6301PIM-SM\/PIM-DM\u5173\u952e\u7279\u6027，\u5305\u62ec\u6ce8\u518c\u505c\u6b62\u673a\u5236\u3002<\/p>\n
2. IGMP\u4ee3\u7406<\/h5>\n
static int ipmr_cache_report(struct mr_table *mrt,
\n struct sk_buff *pkt, vifi_t vifi, int assert)
\n{
\n \/\/ \u6784\u9020IGMPMSG_WHOLEPKT\u6d88\u606f
\n \/\/ \u53d1\u9001\u5230\u7528\u6237\u6001\u5957\u63a5\u5b57
\n}<\/p>\n\u5b9e\u73b0\u7ec4\u64ad\u7ec4\u6210\u5458\u5173\u7cfb\u7684\u8de8\u7f51\u7edc\u4f20\u64ad\u3002<\/p>\n
\n\u4e94\u3001\u521b\u65b0\u8bbe\u8ba1：\u6027\u80fd\u4e0e\u6269\u5c55\u6027<\/h4>\n
- \n
\u591a\u8868\u652f\u6301（CONFIG_IP_MROUTE_MULTIPLE_TABLES）<\/p>\n
struct mr_table *ipmr_new_table(struct net *net, u32 id)
\n{
\n \/\/ \u521b\u5efa\u72ec\u7acb\u8def\u7531\u8868
\n}<\/p>\n\u652f\u6301VRF\u573a\u666f，\u5b9e\u73b0\u7f51\u7edc\u9694\u79bb\u3002<\/p>\n<\/li>\n
- \n
RCU+\u54c8\u5e0c\u8868\u68c0\u7d22<\/p>\n
struct mfc_cache *ipmr_cache_find(struct mr_table *mrt,
\n __be32 origin, __be32 mcastgrp)
\n{
\n \/\/ RCU\u4fdd\u62a4\u7684\u54c8\u5e0c\u67e5\u627e
\n}<\/p>\n\u5b9e\u73b0\u767e\u4e07\u7ea7\u8def\u7531\u6761\u76ee\u4e0b\u7684\u5fae\u79d2\u7ea7\u68c0\u7d22\u3002<\/p>\n<\/li>\n
- \n
\u52a8\u6001\u5b9a\u65f6\u5668\u7ba1\u7406
\n\u4ec5\u5f53\u5b58\u5728\u672a\u89e3\u6790\u6761\u76ee\u65f6\u6fc0\u6d3b\u5b9a\u65f6\u5668，\u51cf\u5c11\u7a7a\u8f6c\u5f00\u9500\u3002<\/p>\n<\/li>\n
\n\u516d\u3001\u5b9e\u6218\u6d1e\u5bdf：\u5b9a\u4f4d\u591a\u64ad\u95ee\u9898\u7684\u5173\u952e\u70b9<\/h4>\n
- \n
\u67e5\u770b\u8def\u7531\u8868<\/p>\n
cat \/proc\/net\/ip_mr_cache
\n# \u8f93\u51fa\u793a\u4f8b：
\n# Group Origin Iif Pkts Bytes Wrong Oifs
\n# E0000001 C0A80101 2 104 8576 0 1:3<\/p>\n\u5173\u6ce8"Wrong Oifs"\u8ba1\u6570，\u9ad8\u6570\u503c\u8868\u660e\u63a5\u53e3\u914d\u7f6e\u9519\u8bef\u3002<\/p>\n<\/li>\n
- \n
\u76d1\u63a7\u865a\u62df\u63a5\u53e3<\/p>\n
cat \/proc\/net\/ip_mr_vif
\n# \u8f93\u51fa\u793a\u4f8b：
\n# Interface BytesIn PktsIn BytesOut PktsOut Flags
\n# vif0 15MB 1200 12MB 900 VIFF_TUNNEL<\/p>\n\u5f02\u5e38\u5b57\u8282\u6570\u6307\u793a\u8def\u7531\u73af\u8def\u6216\u914d\u7f6e\u9519\u8bef\u3002<\/p>\n<\/li>\n
- \n
\u52a8\u6001\u8c03\u8bd5
\n\u542f\u7528\u5185\u6838\u8c03\u8bd5\u9009\u9879：<\/p>\necho 1 > \/proc\/sys\/net\/ipv4\/route\/mcast_debug\n<\/li>\n
\n\u7ed3\u8bed<\/h4>\n
Linux\u7684IPv4\u591a\u64ad\u8def\u7531\u901a\u8fc7\u5206\u5c42\u67b6\u6784\u548c\u52a8\u6001\u7ba1\u7406\u673a\u5236，\u5728\u590d\u6742\u7f51\u7edc\u73af\u5883\u4e2d\u5b9e\u73b0\u4e86\u9ad8\u6548\u7a33\u5b9a\u7684\u6570\u636e\u5206\u53d1\u3002\u5176\u6838\u5fc3\u8bbe\u8ba1\u601d\u60f3\u5305\u62ec：<\/p>\n
- \n
\u63a7\u5236\u4e0e\u8f6c\u53d1\u5206\u79bb：\u7528\u6237\u6001\u534f\u8bae\u5904\u7406+\u5185\u6838\u6001\u5feb\u901f\u8f6c\u53d1<\/p>\n<\/li>\n
- \n
\u65f6\u95f4\u7a7a\u95f4\u5e73\u8861：\u54c8\u5e0c\u8868+\u94fe\u8868\u7684\u6df7\u5408\u5b58\u50a8\u7ed3\u6784<\/p>\n<\/li>\n
- \n
\u60f0\u6027\u8ba1\u7b97：\u6309\u9700\u6fc0\u6d3b\u5904\u7406\u6d41\u7a0b<\/p>\n<\/li>\n
\u8fd9\u4e9b\u8bbe\u8ba1\u4f7f\u5f97Linux\u6210\u4e3a\u4ece\u6570\u636e\u4e2d\u5fc3\u5230\u7535\u4fe1\u7f51\u7edc\u7684\u591a\u64ad\u89e3\u51b3\u65b9\u6848\u57fa\u77f3，\u4e3a5G\u7f51\u7edc\u3001IPTV\u7b49\u573a\u666f\u63d0\u4f9b\u4e86\u5173\u952e\u57fa\u7840\u8bbe\u65bd\u652f\u6301\u3002<\/p>\n
<\/p>\n\/*
\n *IP multicast routing support for mrouted 3.6\/3.8
\n *
\n *(c) 1995 Alan Cox, <alan@lxorguk.ukuu.org.uk>
\n * Linux Consultancy and Custom Driver Development
\n *
\n *This program is free software; you can redistribute it and\/or
\n *modify it under the terms of the GNU General Public License
\n *as published by the Free Software Foundation; either version
\n *2 of the License, or (at your option) any later version.
\n *
\n *Fixes:
\n *Michael Chastain:Incorrect size of copying.
\n *Alan Cox:Added the cache manager code
\n *Alan Cox:Fixed the clone\/copy bug and device race.
\n *Mike McLagan:Routing by source
\n *Malcolm Beattie:Buffer handling fixes.
\n *Alexey Kuznetsov:Double buffer free and other fixes.
\n *SVR Anand:Fixed several multicast bugs and problems.
\n *Alexey Kuznetsov:Status, optimisations and more.
\n *Brad Parker:Better behaviour on mrouted upcall
\n *overflow.
\n * Carlos Picoto : PIMv1 Support
\n *Pavlin Ivanov Radoslavov:PIMv2 Registers must checksum only PIM header
\n *Relax this requirement to work with older peers.
\n *
\n *\/<\/p>\n#include <linux\/uaccess.h>
\n#include <linux\/types.h>
\n#include <linux\/cache.h>
\n#include <linux\/capability.h>
\n#include <linux\/errno.h>
\n#include <linux\/mm.h>
\n#include <linux\/kernel.h>
\n#include <linux\/fcntl.h>
\n#include <linux\/stat.h>
\n#include <linux\/socket.h>
\n#include <linux\/in.h>
\n#include <linux\/inet.h>
\n#include <linux\/netdevice.h>
\n#include <linux\/inetdevice.h>
\n#include <linux\/igmp.h>
\n#include <linux\/proc_fs.h>
\n#include <linux\/seq_file.h>
\n#include <linux\/mroute.h>
\n#include <linux\/init.h>
\n#include <linux\/if_ether.h>
\n#include <linux\/slab.h>
\n#include <net\/net_namespace.h>
\n#include <net\/ip.h>
\n#include <net\/protocol.h>
\n#include <linux\/skbuff.h>
\n#include <net\/route.h>
\n#include <net\/icmp.h>
\n#include <net\/udp.h>
\n#include <net\/raw.h>
\n#include <linux\/notifier.h>
\n#include <linux\/if_arp.h>
\n#include <linux\/netfilter_ipv4.h>
\n#include <linux\/compat.h>
\n#include <linux\/export.h>
\n#include <linux\/rhashtable.h>
\n#include <net\/ip_tunnels.h>
\n#include <net\/checksum.h>
\n#include <net\/netlink.h>
\n#include <net\/fib_rules.h>
\n#include <linux\/netconf.h>
\n#include <net\/nexthop.h>
\n#include <net\/switchdev.h><\/p>\n#include <linux\/nospec.h><\/p>\n
struct ipmr_rule {
\nstruct fib_rulecommon;
\n};<\/p>\nstruct ipmr_result {
\nstruct mr_table*mrt;
\n};<\/p>\n\/* Big lock, protecting vif table, mrt cache and mroute socket state.
\n * Note that the changes are semaphored via rtnl_lock.
\n *\/<\/p>\nstatic DEFINE_RWLOCK(mrt_lock);<\/p>\n
\/* Multicast router control variables *\/<\/p>\n
\/* Special spinlock for queue of unresolved entries *\/
\nstatic DEFINE_SPINLOCK(mfc_unres_lock);<\/p>\n\/* We return to original Alan's scheme. Hash table of resolved
\n * entries is changed only in process context and protected
\n * with weak lock mrt_lock. Queue of unresolved entries is protected
\n * with strong spinlock mfc_unres_lock.
\n *
\n * In this case data path is free of exclusive locks at all.
\n *\/<\/p>\nstatic struct kmem_cache *mrt_cachep __ro_after_init;<\/p>\n
static struct mr_table *ipmr_new_table(struct net *net, u32 id);
\nstatic void ipmr_free_table(struct mr_table *mrt);<\/p>\nstatic void ip_mr_forward(struct net *net, struct mr_table *mrt,
\n struct net_device *dev, struct sk_buff *skb,
\n struct mfc_cache *cache, int local);
\nstatic int ipmr_cache_report(struct mr_table *mrt,
\n struct sk_buff *pkt, vifi_t vifi, int assert);
\nstatic void mroute_netlink_event(struct mr_table *mrt, struct mfc_cache *mfc,
\n int cmd);
\nstatic void igmpmsg_netlink_event(struct mr_table *mrt, struct sk_buff *pkt);
\nstatic void mroute_clean_tables(struct mr_table *mrt, bool all);
\nstatic void ipmr_expire_process(struct timer_list *t);<\/p>\n#ifdef CONFIG_IP_MROUTE_MULTIPLE_TABLES
\n#define ipmr_for_each_table(mrt, net) \\\\
\nlist_for_each_entry_rcu(mrt, &net->ipv4.mr_tables, list)<\/p>\nstatic struct mr_table *ipmr_mr_table_iter(struct net *net,
\n struct mr_table *mrt)
\n{
\nstruct mr_table *ret;<\/p>\nif (!mrt)
\nret = list_entry_rcu(net->ipv4.mr_tables.next,
\n struct mr_table, list);
\nelse
\nret = list_entry_rcu(mrt->list.next,
\n struct mr_table, list);<\/p>\nif (&ret->list == &net->ipv4.mr_tables)
\nreturn NULL;
\nreturn ret;
\n}<\/p>\nstatic struct mr_table *ipmr_get_table(struct net *net, u32 id)
\n{
\nstruct mr_table *mrt;<\/p>\nipmr_for_each_table(mrt, net) {
\nif (mrt->id == id)
\nreturn mrt;
\n}
\nreturn NULL;
\n}<\/p>\nstatic int ipmr_fib_lookup(struct net *net, struct flowi4 *flp4,
\n struct mr_table **mrt)
\n{
\nint err;
\nstruct ipmr_result res;
\nstruct fib_lookup_arg arg = {
\n.result = &res,
\n.flags = FIB_LOOKUP_NOREF,
\n};<\/p>\n\/* update flow if oif or iif point to device enslaved to l3mdev *\/
\nl3mdev_update_flow(net, flowi4_to_flowi(flp4));<\/p>\nerr = fib_rules_lookup(net->ipv4.mr_rules_ops,
\n flowi4_to_flowi(flp4), 0, &arg);
\nif (err < 0)
\nreturn err;
\n*mrt = res.mrt;
\nreturn 0;
\n}<\/p>\nstatic int ipmr_rule_action(struct fib_rule *rule, struct flowi *flp,
\n int flags, struct fib_lookup_arg *arg)
\n{
\nstruct ipmr_result *res = arg->result;
\nstruct mr_table *mrt;<\/p>\nswitch (rule->action) {
\ncase FR_ACT_TO_TBL:
\nbreak;
\ncase FR_ACT_UNREACHABLE:
\nreturn -ENETUNREACH;
\ncase FR_ACT_PROHIBIT:
\nreturn -EACCES;
\ncase FR_ACT_BLACKHOLE:
\ndefault:
\nreturn -EINVAL;
\n}<\/p>\narg->table = fib_rule_get_table(rule, arg);<\/p>\n
mrt = ipmr_get_table(rule->fr_net, arg->table);
\nif (!mrt)
\nreturn -EAGAIN;
\nres->mrt = mrt;
\nreturn 0;
\n}<\/p>\nstatic int ipmr_rule_match(struct fib_rule *rule, struct flowi *fl, int flags)
\n{
\nreturn 1;
\n}<\/p>\nstatic const struct nla_policy ipmr_rule_policy[FRA_MAX + 1] = {
\nFRA_GENERIC_POLICY,
\n};<\/p>\nstatic int ipmr_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
\n struct fib_rule_hdr *frh, struct nlattr **tb,
\n struct netlink_ext_ack *extack)
\n{
\nreturn 0;
\n}<\/p>\nstatic int ipmr_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
\n struct nlattr **tb)
\n{
\nreturn 1;
\n}<\/p>\nstatic int ipmr_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
\n struct fib_rule_hdr *frh)
\n{
\nfrh->dst_len = 0;
\nfrh->src_len = 0;
\nfrh->tos = 0;
\nreturn 0;
\n}<\/p>\nstatic const struct fib_rules_ops __net_initconst ipmr_rules_ops_template = {
\n.family= RTNL_FAMILY_IPMR,
\n.rule_size= sizeof(struct ipmr_rule),
\n.addr_size= sizeof(u32),
\n.action= ipmr_rule_action,
\n.match= ipmr_rule_match,
\n.configure= ipmr_rule_configure,
\n.compare= ipmr_rule_compare,
\n.fill= ipmr_rule_fill,
\n.nlgroup= RTNLGRP_IPV4_RULE,
\n.policy= ipmr_rule_policy,
\n.owner= THIS_MODULE,
\n};<\/p>\nstatic int __net_init ipmr_rules_init(struct net *net)
\n{
\nstruct fib_rules_ops *ops;
\nstruct mr_table *mrt;
\nint err;<\/p>\nops = fib_rules_register(&ipmr_rules_ops_template, net);
\nif (IS_ERR(ops))
\nreturn PTR_ERR(ops);<\/p>\nINIT_LIST_HEAD(&net->ipv4.mr_tables);<\/p>\n
mrt = ipmr_new_table(net, RT_TABLE_DEFAULT);
\nif (IS_ERR(mrt)) {
\nerr = PTR_ERR(mrt);
\ngoto err1;
\n}<\/p>\nerr = fib_default_rule_add(ops, 0x7fff, RT_TABLE_DEFAULT, 0);
\nif (err < 0)
\ngoto err2;<\/p>\nnet->ipv4.mr_rules_ops = ops;
\nreturn 0;<\/p>\nerr2:
\nipmr_free_table(mrt);
\nerr1:
\nfib_rules_unregister(ops);
\nreturn err;
\n}<\/p>\nstatic void __net_exit ipmr_rules_exit(struct net *net)
\n{
\nstruct mr_table *mrt, *next;<\/p>\nrtnl_lock();
\nlist_for_each_entry_safe(mrt, next, &net->ipv4.mr_tables, list) {
\nlist_del(&mrt->list);
\nipmr_free_table(mrt);
\n}
\nfib_rules_unregister(net->ipv4.mr_rules_ops);
\nrtnl_unlock();
\n}<\/p>\nstatic int ipmr_rules_dump(struct net *net, struct notifier_block *nb)
\n{
\nreturn fib_rules_dump(net, nb, RTNL_FAMILY_IPMR);
\n}<\/p>\nstatic unsigned int ipmr_rules_seq_read(struct net *net)
\n{
\nreturn fib_rules_seq_read(net, RTNL_FAMILY_IPMR);
\n}<\/p>\nbool ipmr_rule_default(const struct fib_rule *rule)
\n{
\nreturn fib_rule_matchall(rule) && rule->table == RT_TABLE_DEFAULT;
\n}
\nEXPORT_SYMBOL(ipmr_rule_default);
\n#else
\n#define ipmr_for_each_table(mrt, net) \\\\
\nfor (mrt = net->ipv4.mrt; mrt; mrt = NULL)<\/p>\nstatic struct mr_table *ipmr_mr_table_iter(struct net *net,
\n struct mr_table *mrt)
\n{
\nif (!mrt)
\nreturn net->ipv4.mrt;
\nreturn NULL;
\n}<\/p>\nstatic struct mr_table *ipmr_get_table(struct net *net, u32 id)
\n{
\nreturn net->ipv4.mrt;
\n}<\/p>\nstatic int ipmr_fib_lookup(struct net *net, struct flowi4 *flp4,
\n struct mr_table **mrt)
\n{
\n*mrt = net->ipv4.mrt;
\nreturn 0;
\n}<\/p>\nstatic int __net_init ipmr_rules_init(struct net *net)
\n{
\nstruct mr_table *mrt;<\/p>\nmrt = ipmr_new_table(net, RT_TABLE_DEFAULT);
\nif (IS_ERR(mrt))
\nreturn PTR_ERR(mrt);
\nnet->ipv4.mrt = mrt;
\nreturn 0;
\n}<\/p>\nstatic void __net_exit ipmr_rules_exit(struct net *net)
\n{
\nrtnl_lock();
\nipmr_free_table(net->ipv4.mrt);
\nnet->ipv4.mrt = NULL;
\nrtnl_unlock();
\n}<\/p>\nstatic int ipmr_rules_dump(struct net *net, struct notifier_block *nb)
\n{
\nreturn 0;
\n}<\/p>\nstatic unsigned int ipmr_rules_seq_read(struct net *net)
\n{
\nreturn 0;
\n}<\/p>\nbool ipmr_rule_default(const struct fib_rule *rule)
\n{
\nreturn true;
\n}
\nEXPORT_SYMBOL(ipmr_rule_default);
\n#endif<\/p>\nstatic inline int ipmr_hash_cmp(struct rhashtable_compare_arg *arg,
\nconst void *ptr)
\n{
\nconst struct mfc_cache_cmp_arg *cmparg = arg->key;
\nstruct mfc_cache *c = (struct mfc_cache *)ptr;<\/p>\nreturn cmparg->mfc_mcastgrp != c->mfc_mcastgrp ||
\n cmparg->mfc_origin != c->mfc_origin;
\n}<\/p>\nstatic const struct rhashtable_params ipmr_rht_params = {
\n.head_offset = offsetof(struct mr_mfc, mnode),
\n.key_offset = offsetof(struct mfc_cache, cmparg),
\n.key_len = sizeof(struct mfc_cache_cmp_arg),
\n.nelem_hint = 3,
\n.locks_mul = 1,
\n.obj_cmpfn = ipmr_hash_cmp,
\n.automatic_shrinking = true,
\n};<\/p>\nstatic void ipmr_new_table_set(struct mr_table *mrt,
\n struct net *net)
\n{
\n#ifdef CONFIG_IP_MROUTE_MULTIPLE_TABLES
\nlist_add_tail_rcu(&mrt->list, &net->ipv4.mr_tables);
\n#endif
\n}<\/p>\nstatic struct mfc_cache_cmp_arg ipmr_mr_table_ops_cmparg_any = {
\n.mfc_mcastgrp = htonl(INADDR_ANY),
\n.mfc_origin = htonl(INADDR_ANY),
\n};<\/p>\nstatic struct mr_table_ops ipmr_mr_table_ops = {
\n.rht_params = &ipmr_rht_params,
\n.cmparg_any = &ipmr_mr_table_ops_cmparg_any,
\n};<\/p>\nstatic struct mr_table *ipmr_new_table(struct net *net, u32 id)
\n{
\nstruct mr_table *mrt;<\/p>\n\/* "pimreg%u" should not exceed 16 bytes (IFNAMSIZ) *\/
\nif (id != RT_TABLE_DEFAULT && id >= 1000000000)
\nreturn ERR_PTR(-EINVAL);<\/p>\nmrt = ipmr_get_table(net, id);
\nif (mrt)
\nreturn mrt;<\/p>\nreturn mr_table_alloc(net, id, &ipmr_mr_table_ops,
\n ipmr_expire_process, ipmr_new_table_set);
\n}<\/p>\nstatic void ipmr_free_table(struct mr_table *mrt)
\n{
\ndel_timer_sync(&mrt->ipmr_expire_timer);
\nmroute_clean_tables(mrt, true);
\nrhltable_destroy(&mrt->mfc_hash);
\nkfree(mrt);
\n}<\/p>\n\/* Service routines creating virtual interfaces: DVMRP tunnels and PIMREG *\/<\/p>\n
static void ipmr_del_tunnel(struct net_device *dev, struct vifctl *v)
\n{
\nstruct net *net = dev_net(dev);<\/p>\ndev_close(dev);<\/p>\n
dev = __dev_get_by_name(net, "tunl0");
\nif (dev) {
\nconst struct net_device_ops *ops = dev->netdev_ops;
\nstruct ifreq ifr;
\nstruct ip_tunnel_parm p;<\/p>\nmemset(&p, 0, sizeof(p));
\np.iph.daddr = v->vifc_rmt_addr.s_addr;
\np.iph.saddr = v->vifc_lcl_addr.s_addr;
\np.iph.version = 4;
\np.iph.ihl = 5;
\np.iph.protocol = IPPROTO_IPIP;
\nsprintf(p.name, "dvmrp%d", v->vifc_vifi);
\nifr.ifr_ifru.ifru_data = (__force void __user *)&p;<\/p>\nif (ops->ndo_do_ioctl) {
\nmm_segment_t oldfs = get_fs();<\/p>\nset_fs(KERNEL_DS);
\nops->ndo_do_ioctl(dev, &ifr, SIOCDELTUNNEL);
\nset_fs(oldfs);
\n}
\n}
\n}<\/p>\n\/* Initialize ipmr pimreg\/tunnel in_device *\/
\nstatic bool ipmr_init_vif_indev(const struct net_device *dev)
\n{
\nstruct in_device *in_dev;<\/p>\nASSERT_RTNL();<\/p>\n
in_dev = __in_dev_get_rtnl(dev);
\nif (!in_dev)
\nreturn false;
\nipv4_devconf_setall(in_dev);
\nneigh_parms_data_state_setall(in_dev->arp_parms);
\nIPV4_DEVCONF(in_dev->cnf, RP_FILTER) = 0;<\/p>\nreturn true;
\n}<\/p>\nstatic struct net_device *ipmr_new_tunnel(struct net *net, struct vifctl *v)
\n{
\nstruct net_device *dev;<\/p>\ndev = __dev_get_by_name(net, "tunl0");<\/p>\n
if (dev) {
\nconst struct net_device_ops *ops = dev->netdev_ops;
\nint err;
\nstruct ifreq ifr;
\nstruct ip_tunnel_parm p;<\/p>\nmemset(&p, 0, sizeof(p));
\np.iph.daddr = v->vifc_rmt_addr.s_addr;
\np.iph.saddr = v->vifc_lcl_addr.s_addr;
\np.iph.version = 4;
\np.iph.ihl = 5;
\np.iph.protocol = IPPROTO_IPIP;
\nsprintf(p.name, "dvmrp%d", v->vifc_vifi);
\nifr.ifr_ifru.ifru_data = (__force void __user *)&p;<\/p>\nif (ops->ndo_do_ioctl) {
\nmm_segment_t oldfs = get_fs();<\/p>\nset_fs(KERNEL_DS);
\nerr = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
\nset_fs(oldfs);
\n} else {
\nerr = -EOPNOTSUPP;
\n}
\ndev = NULL;<\/p>\nif (err == 0 &&
\n (dev = __dev_get_by_name(net, p.name)) != NULL) {
\ndev->flags |= IFF_MULTICAST;
\nif (!ipmr_init_vif_indev(dev))
\ngoto failure;
\nif (dev_open(dev))
\ngoto failure;
\ndev_hold(dev);
\n}
\n}
\nreturn dev;<\/p>\nfailure:
\nunregister_netdevice(dev);
\nreturn NULL;
\n}<\/p>\n#if defined(CONFIG_IP_PIMSM_V1) || defined(CONFIG_IP_PIMSM_V2)
\nstatic netdev_tx_t reg_vif_xmit(struct sk_buff *skb, struct net_device *dev)
\n{
\nstruct net *net = dev_net(dev);
\nstruct mr_table *mrt;
\nstruct flowi4 fl4 = {
\n.flowi4_oif= dev->ifindex,
\n.flowi4_iif= skb->skb_iif ? : LOOPBACK_IFINDEX,
\n.flowi4_mark= skb->mark,
\n};
\nint err;<\/p>\nerr = ipmr_fib_lookup(net, &fl4, &mrt);
\nif (err < 0) {
\nkfree_skb(skb);
\nreturn err;
\n}<\/p>\nread_lock(&mrt_lock);
\ndev->stats.tx_bytes += skb->len;
\ndev->stats.tx_packets++;
\nipmr_cache_report(mrt, skb, mrt->mroute_reg_vif_num, IGMPMSG_WHOLEPKT);
\nread_unlock(&mrt_lock);
\nkfree_skb(skb);
\nreturn NETDEV_TX_OK;
\n}<\/p>\nstatic int reg_vif_get_iflink(const struct net_device *dev)
\n{
\nreturn 0;
\n}<\/p>\nstatic const struct net_device_ops reg_vif_netdev_ops = {
\n.ndo_start_xmit= reg_vif_xmit,
\n.ndo_get_iflink = reg_vif_get_iflink,
\n};<\/p>\nstatic void reg_vif_setup(struct net_device *dev)
\n{
\ndev->type= ARPHRD_PIMREG;
\ndev->mtu= ETH_DATA_LEN – sizeof(struct iphdr) – 8;
\ndev->flags= IFF_NOARP;
\ndev->netdev_ops= ®_vif_netdev_ops;
\ndev->needs_free_netdev= true;
\ndev->features|= NETIF_F_NETNS_LOCAL;
\n}<\/p>\nstatic struct net_device *ipmr_reg_vif(struct net *net, struct mr_table *mrt)
\n{
\nstruct net_device *dev;
\nchar name[IFNAMSIZ];<\/p>\nif (mrt->id == RT_TABLE_DEFAULT)
\nsprintf(name, "pimreg");
\nelse
\nsprintf(name, "pimreg%u", mrt->id);<\/p>\ndev = alloc_netdev(0, name, NET_NAME_UNKNOWN, reg_vif_setup);<\/p>\n
if (!dev)
\nreturn NULL;<\/p>\ndev_net_set(dev, net);<\/p>\n
if (register_netdevice(dev)) {
\nfree_netdev(dev);
\nreturn NULL;
\n}<\/p>\nif (!ipmr_init_vif_indev(dev))
\ngoto failure;
\nif (dev_open(dev))
\ngoto failure;<\/p>\ndev_hold(dev);<\/p>\n
return dev;<\/p>\n
failure:
\nunregister_netdevice(dev);
\nreturn NULL;
\n}<\/p>\n\/* called with rcu_read_lock() *\/
\nstatic int __pim_rcv(struct mr_table *mrt, struct sk_buff *skb,
\n unsigned int pimlen)
\n{
\nstruct net_device *reg_dev = NULL;
\nstruct iphdr *encap;<\/p>\nencap = (struct iphdr *)(skb_transport_header(skb) + pimlen);
\n\/* Check that:
\n * a. packet is really sent to a multicast group
\n * b. packet is not a NULL-REGISTER
\n * c. packet is not truncated
\n *\/
\nif (!ipv4_is_multicast(encap->daddr) ||
\n encap->tot_len == 0 ||
\n ntohs(encap->tot_len) + pimlen > skb->len)
\nreturn 1;<\/p>\nread_lock(&mrt_lock);
\nif (mrt->mroute_reg_vif_num >= 0)
\nreg_dev = mrt->vif_table[mrt->mroute_reg_vif_num].dev;
\nread_unlock(&mrt_lock);<\/p>\nif (!reg_dev)
\nreturn 1;<\/p>\nskb->mac_header = skb->network_header;
\nskb_pull(skb, (u8 *)encap – skb->data);
\nskb_reset_network_header(skb);
\nskb->protocol = htons(ETH_P_IP);
\nskb->ip_summed = CHECKSUM_NONE;<\/p>\nskb_tunnel_rx(skb, reg_dev, dev_net(reg_dev));<\/p>\n
netif_rx(skb);<\/p>\n
return NET_RX_SUCCESS;
\n}
\n#else
\nstatic struct net_device *ipmr_reg_vif(struct net *net, struct mr_table *mrt)
\n{
\nreturn NULL;
\n}
\n#endif<\/p>\nstatic int call_ipmr_vif_entry_notifiers(struct net *net,
\n enum fib_event_type event_type,
\n struct vif_device *vif,
\n vifi_t vif_index, u32 tb_id)
\n{
\nreturn mr_call_vif_notifiers(net, RTNL_FAMILY_IPMR, event_type,
\n vif, vif_index, tb_id,
\n &net->ipv4.ipmr_seq);
\n}<\/p>\nstatic int call_ipmr_mfc_entry_notifiers(struct net *net,
\n enum fib_event_type event_type,
\n struct mfc_cache *mfc, u32 tb_id)
\n{
\nreturn mr_call_mfc_notifiers(net, RTNL_FAMILY_IPMR, event_type,
\n &mfc->_c, tb_id, &net->ipv4.ipmr_seq);
\n}<\/p>\n\/**
\n *vif_delete – Delete a VIF entry
\n *@notify: Set to 1, if the caller is a notifier_call
\n *\/
\nstatic int vif_delete(struct mr_table *mrt, int vifi, int notify,
\n struct list_head *head)
\n{
\nstruct net *net = read_pnet(&mrt->net);
\nstruct vif_device *v;
\nstruct net_device *dev;
\nstruct in_device *in_dev;<\/p>\nif (vifi < 0 || vifi >= mrt->maxvif)
\nreturn -EADDRNOTAVAIL;<\/p>\nv = &mrt->vif_table[vifi];<\/p>\n
if (VIF_EXISTS(mrt, vifi))
\ncall_ipmr_vif_entry_notifiers(net, FIB_EVENT_VIF_DEL, v, vifi,
\n mrt->id);<\/p>\nwrite_lock_bh(&mrt_lock);
\ndev = v->dev;
\nv->dev = NULL;<\/p>\nif (!dev) {
\nwrite_unlock_bh(&mrt_lock);
\nreturn -EADDRNOTAVAIL;
\n}<\/p>\nif (vifi == mrt->mroute_reg_vif_num)
\nmrt->mroute_reg_vif_num = -1;<\/p>\nif (vifi + 1 == mrt->maxvif) {
\nint tmp;<\/p>\nfor (tmp = vifi – 1; tmp >= 0; tmp–) {
\nif (VIF_EXISTS(mrt, tmp))
\nbreak;
\n}
\nmrt->maxvif = tmp+1;
\n}<\/p>\nwrite_unlock_bh(&mrt_lock);<\/p>\n
dev_set_allmulti(dev, -1);<\/p>\n
in_dev = __in_dev_get_rtnl(dev);
\nif (in_dev) {
\nIPV4_DEVCONF(in_dev->cnf, MC_FORWARDING)–;
\ninet_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
\n NETCONFA_MC_FORWARDING,
\n dev->ifindex, &in_dev->cnf);
\nip_rt_multicast_event(in_dev);
\n}<\/p>\nif (v->flags & (VIFF_TUNNEL | VIFF_REGISTER) && !notify)
\nunregister_netdevice_queue(dev, head);<\/p>\ndev_put(dev);
\nreturn 0;
\n}<\/p>\nstatic void ipmr_cache_free_rcu(struct rcu_head *head)
\n{
\nstruct mr_mfc *c = container_of(head, struct mr_mfc, rcu);<\/p>\nkmem_cache_free(mrt_cachep, (struct mfc_cache *)c);
\n}<\/p>\nstatic void ipmr_cache_free(struct mfc_cache *c)
\n{
\ncall_rcu(&c->_c.rcu, ipmr_cache_free_rcu);
\n}<\/p>\n\/* Destroy an unresolved cache entry, killing queued skbs
\n * and reporting error to netlink readers.
\n *\/
\nstatic void ipmr_destroy_unres(struct mr_table *mrt, struct mfc_cache *c)
\n{
\nstruct net *net = read_pnet(&mrt->net);
\nstruct sk_buff *skb;
\nstruct nlmsgerr *e;<\/p>\natomic_dec(&mrt->cache_resolve_queue_len);<\/p>\n
while ((skb = skb_dequeue(&c->_c.mfc_un.unres.unresolved))) {
\nif (ip_hdr(skb)->version == 0) {
\nstruct nlmsghdr *nlh = skb_pull(skb,
\nsizeof(struct iphdr));
\nnlh->nlmsg_type = NLMSG_ERROR;
\nnlh->nlmsg_len = nlmsg_msg_size(sizeof(struct nlmsgerr));
\nskb_trim(skb, nlh->nlmsg_len);
\ne = nlmsg_data(nlh);
\ne->error = -ETIMEDOUT;
\nmemset(&e->msg, 0, sizeof(e->msg));<\/p>\nrtnl_unicast(skb, net, NETLINK_CB(skb).portid);
\n} else {
\nkfree_skb(skb);
\n}
\n}<\/p>\nipmr_cache_free(c);
\n}<\/p>\n\/* Timer process for the unresolved queue. *\/
\nstatic void ipmr_expire_process(struct timer_list *t)
\n{
\nstruct mr_table *mrt = from_timer(mrt, t, ipmr_expire_timer);
\nstruct mr_mfc *c, *next;
\nunsigned long expires;
\nunsigned long now;<\/p>\nif (!spin_trylock(&mfc_unres_lock)) {
\nmod_timer(&mrt->ipmr_expire_timer, jiffies+HZ\/10);
\nreturn;
\n}<\/p>\nif (list_empty(&mrt->mfc_unres_queue))
\ngoto out;<\/p>\nnow = jiffies;
\nexpires = 10*HZ;<\/p>\nlist_for_each_entry_safe(c, next, &mrt->mfc_unres_queue, list) {
\nif (time_after(c->mfc_un.unres.expires, now)) {
\nunsigned long interval = c->mfc_un.unres.expires – now;
\nif (interval < expires)
\nexpires = interval;
\ncontinue;
\n}<\/p>\nlist_del(&c->list);
\nmroute_netlink_event(mrt, (struct mfc_cache *)c, RTM_DELROUTE);
\nipmr_destroy_unres(mrt, (struct mfc_cache *)c);
\n}<\/p>\nif (!list_empty(&mrt->mfc_unres_queue))
\nmod_timer(&mrt->ipmr_expire_timer, jiffies + expires);<\/p>\nout:
\nspin_unlock(&mfc_unres_lock);
\n}<\/p>\n\/* Fill oifs list. It is called under write locked mrt_lock. *\/
\nstatic void ipmr_update_thresholds(struct mr_table *mrt, struct mr_mfc *cache,
\n unsigned char *ttls)
\n{
\nint vifi;<\/p>\ncache->mfc_un.res.minvif = MAXVIFS;
\ncache->mfc_un.res.maxvif = 0;
\nmemset(cache->mfc_un.res.ttls, 255, MAXVIFS);<\/p>\nfor (vifi = 0; vifi < mrt->maxvif; vifi++) {
\nif (VIF_EXISTS(mrt, vifi) &&
\n ttls[vifi] && ttls[vifi] < 255) {
\ncache->mfc_un.res.ttls[vifi] = ttls[vifi];
\nif (cache->mfc_un.res.minvif > vifi)
\ncache->mfc_un.res.minvif = vifi;
\nif (cache->mfc_un.res.maxvif <= vifi)
\ncache->mfc_un.res.maxvif = vifi + 1;
\n}
\n}
\ncache->mfc_un.res.lastuse = jiffies;
\n}<\/p>\nstatic int vif_add(struct net *net, struct mr_table *mrt,
\n struct vifctl *vifc, int mrtsock)
\n{
\nint vifi = vifc->vifc_vifi;
\nstruct switchdev_attr attr = {
\n.id = SWITCHDEV_ATTR_ID_PORT_PARENT_ID,
\n};
\nstruct vif_device *v = &mrt->vif_table[vifi];
\nstruct net_device *dev;
\nstruct in_device *in_dev;
\nint err;<\/p>\n\/* Is vif busy ? *\/
\nif (VIF_EXISTS(mrt, vifi))
\nreturn -EADDRINUSE;<\/p>\nswitch (vifc->vifc_flags) {
\ncase VIFF_REGISTER:
\nif (!ipmr_pimsm_enabled())
\nreturn -EINVAL;
\n\/* Special Purpose VIF in PIM
\n * All the packets will be sent to the daemon
\n *\/
\nif (mrt->mroute_reg_vif_num >= 0)
\nreturn -EADDRINUSE;
\ndev = ipmr_reg_vif(net, mrt);
\nif (!dev)
\nreturn -ENOBUFS;
\nerr = dev_set_allmulti(dev, 1);
\nif (err) {
\nunregister_netdevice(dev);
\ndev_put(dev);
\nreturn err;
\n}
\nbreak;
\ncase VIFF_TUNNEL:
\ndev = ipmr_new_tunnel(net, vifc);
\nif (!dev)
\nreturn -ENOBUFS;
\nerr = dev_set_allmulti(dev, 1);
\nif (err) {
\nipmr_del_tunnel(dev, vifc);
\ndev_put(dev);
\nreturn err;
\n}
\nbreak;
\ncase VIFF_USE_IFINDEX:
\ncase 0:
\nif (vifc->vifc_flags == VIFF_USE_IFINDEX) {
\ndev = dev_get_by_index(net, vifc->vifc_lcl_ifindex);
\nif (dev && !__in_dev_get_rtnl(dev)) {
\ndev_put(dev);
\nreturn -EADDRNOTAVAIL;
\n}
\n} else {
\ndev = ip_dev_find(net, vifc->vifc_lcl_addr.s_addr);
\n}
\nif (!dev)
\nreturn -EADDRNOTAVAIL;
\nerr = dev_set_allmulti(dev, 1);
\nif (err) {
\ndev_put(dev);
\nreturn err;
\n}
\nbreak;
\ndefault:
\nreturn -EINVAL;
\n}<\/p>\nin_dev = __in_dev_get_rtnl(dev);
\nif (!in_dev) {
\ndev_put(dev);
\nreturn -EADDRNOTAVAIL;
\n}
\nIPV4_DEVCONF(in_dev->cnf, MC_FORWARDING)++;
\ninet_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_MC_FORWARDING,
\n dev->ifindex, &in_dev->cnf);
\nip_rt_multicast_event(in_dev);<\/p>\n\/* Fill in the VIF structures *\/
\nvif_device_init(v, dev, vifc->vifc_rate_limit,
\nvifc->vifc_threshold,
\nvifc->vifc_flags | (!mrtsock ? VIFF_STATIC : 0),
\n(VIFF_TUNNEL | VIFF_REGISTER));<\/p>\nattr.orig_dev = dev;
\nif (!switchdev_port_attr_get(dev, &attr)) {
\nmemcpy(v->dev_parent_id.id, attr.u.ppid.id, attr.u.ppid.id_len);
\nv->dev_parent_id.id_len = attr.u.ppid.id_len;
\n} else {
\nv->dev_parent_id.id_len = 0;
\n}<\/p>\nv->local = vifc->vifc_lcl_addr.s_addr;
\nv->remote = vifc->vifc_rmt_addr.s_addr;<\/p>\n\/* And finish update writing critical data *\/
\nwrite_lock_bh(&mrt_lock);
\nv->dev = dev;
\nif (v->flags & VIFF_REGISTER)
\nmrt->mroute_reg_vif_num = vifi;
\nif (vifi+1 > mrt->maxvif)
\nmrt->maxvif = vifi+1;
\nwrite_unlock_bh(&mrt_lock);
\ncall_ipmr_vif_entry_notifiers(net, FIB_EVENT_VIF_ADD, v, vifi, mrt->id);
\nreturn 0;
\n}<\/p>\n\/* called with rcu_read_lock() *\/
\nstatic struct mfc_cache *ipmr_cache_find(struct mr_table *mrt,
\n __be32 origin,
\n __be32 mcastgrp)
\n{
\nstruct mfc_cache_cmp_arg arg = {
\n.mfc_mcastgrp = mcastgrp,
\n.mfc_origin = origin
\n};<\/p>\nreturn mr_mfc_find(mrt, &arg);
\n}<\/p>\n\/* Look for a (*,G) entry *\/
\nstatic struct mfc_cache *ipmr_cache_find_any(struct mr_table *mrt,
\n __be32 mcastgrp, int vifi)
\n{
\nstruct mfc_cache_cmp_arg arg = {
\n.mfc_mcastgrp = mcastgrp,
\n.mfc_origin = htonl(INADDR_ANY)
\n};<\/p>\nif (mcastgrp == htonl(INADDR_ANY))
\nreturn mr_mfc_find_any_parent(mrt, vifi);
\nreturn mr_mfc_find_any(mrt, vifi, &arg);
\n}<\/p>\n\/* Look for a (S,G,iif) entry if parent != -1 *\/
\nstatic struct mfc_cache *ipmr_cache_find_parent(struct mr_table *mrt,
\n__be32 origin, __be32 mcastgrp,
\nint parent)
\n{
\nstruct mfc_cache_cmp_arg arg = {
\n.mfc_mcastgrp = mcastgrp,
\n.mfc_origin = origin,
\n};<\/p>\nreturn mr_mfc_find_parent(mrt, &arg, parent);
\n}<\/p>\n\/* Allocate a multicast cache entry *\/
\nstatic struct mfc_cache *ipmr_cache_alloc(void)
\n{
\nstruct mfc_cache *c = kmem_cache_zalloc(mrt_cachep, GFP_KERNEL);<\/p>\nif (c) {
\nc->_c.mfc_un.res.last_assert = jiffies – MFC_ASSERT_THRESH – 1;
\nc->_c.mfc_un.res.minvif = MAXVIFS;
\nc->_c.free = ipmr_cache_free_rcu;
\nrefcount_set(&c->_c.mfc_un.res.refcount, 1);
\n}
\nreturn c;
\n}<\/p>\nstatic struct mfc_cache *ipmr_cache_alloc_unres(void)
\n{
\nstruct mfc_cache *c = kmem_cache_zalloc(mrt_cachep, GFP_ATOMIC);<\/p>\nif (c) {
\nskb_queue_head_init(&c->_c.mfc_un.unres.unresolved);
\nc->_c.mfc_un.unres.expires = jiffies + 10 * HZ;
\n}
\nreturn c;
\n}<\/p>\n\/* A cache entry has gone into a resolved state from queued *\/
\nstatic void ipmr_cache_resolve(struct net *net, struct mr_table *mrt,
\n struct mfc_cache *uc, struct mfc_cache *c)
\n{
\nstruct sk_buff *skb;
\nstruct nlmsgerr *e;<\/p>\n\/* Play the pending entries through our router *\/
\nwhile ((skb = __skb_dequeue(&uc->_c.mfc_un.unres.unresolved))) {
\nif (ip_hdr(skb)->version == 0) {
\nstruct nlmsghdr *nlh = skb_pull(skb,
\nsizeof(struct iphdr));<\/p>\nif (mr_fill_mroute(mrt, skb, &c->_c,
\n nlmsg_data(nlh)) > 0) {
\nnlh->nlmsg_len = skb_tail_pointer(skb) –
\n (u8 *)nlh;
\n} else {
\nnlh->nlmsg_type = NLMSG_ERROR;
\nnlh->nlmsg_len = nlmsg_msg_size(sizeof(struct nlmsgerr));
\nskb_trim(skb, nlh->nlmsg_len);
\ne = nlmsg_data(nlh);
\ne->error = -EMSGSIZE;
\nmemset(&e->msg, 0, sizeof(e->msg));
\n}<\/p>\nrtnl_unicast(skb, net, NETLINK_CB(skb).portid);
\n} else {
\nip_mr_forward(net, mrt, skb->dev, skb, c, 0);
\n}
\n}
\n}<\/p>\n\/* Bounce a cache query up to mrouted and netlink.
\n *
\n * Called under mrt_lock.
\n *\/
\nstatic int ipmr_cache_report(struct mr_table *mrt,
\n struct sk_buff *pkt, vifi_t vifi, int assert)
\n{
\nconst int ihl = ip_hdrlen(pkt);
\nstruct sock *mroute_sk;
\nstruct igmphdr *igmp;
\nstruct igmpmsg *msg;
\nstruct sk_buff *skb;
\nint ret;<\/p>\nif (assert == IGMPMSG_WHOLEPKT || assert == IGMPMSG_WRVIFWHOLE)
\nskb = skb_realloc_headroom(pkt, sizeof(struct iphdr));
\nelse
\nskb = alloc_skb(128, GFP_ATOMIC);<\/p>\nif (!skb)
\nreturn -ENOBUFS;<\/p>\nif (assert == IGMPMSG_WHOLEPKT || assert == IGMPMSG_WRVIFWHOLE) {
\n\/* Ugly, but we have no choice with this interface.
\n * Duplicate old header, fix ihl, length etc.
\n * And all this only to mangle msg->im_msgtype and
\n * to set msg->im_mbz to "mbz" \ud83d\ude42
\n *\/
\nskb_push(skb, sizeof(struct iphdr));
\nskb_reset_network_header(skb);
\nskb_reset_transport_header(skb);
\nmsg = (struct igmpmsg *)skb_network_header(skb);
\nmemcpy(msg, skb_network_header(pkt), sizeof(struct iphdr));
\nmsg->im_msgtype = assert;
\nmsg->im_mbz = 0;
\nif (assert == IGMPMSG_WRVIFWHOLE)
\nmsg->im_vif = vifi;
\nelse
\nmsg->im_vif = mrt->mroute_reg_vif_num;
\nip_hdr(skb)->ihl = sizeof(struct iphdr) >> 2;
\nip_hdr(skb)->tot_len = htons(ntohs(ip_hdr(pkt)->tot_len) +
\n sizeof(struct iphdr));
\n} else {
\n\/* Copy the IP header *\/
\nskb_set_network_header(skb, skb->len);
\nskb_put(skb, ihl);
\nskb_copy_to_linear_data(skb, pkt->data, ihl);
\n\/* Flag to the kernel this is a route add *\/
\nip_hdr(skb)->protocol = 0;
\nmsg = (struct igmpmsg *)skb_network_header(skb);
\nmsg->im_vif = vifi;
\nskb_dst_set(skb, dst_clone(skb_dst(pkt)));
\n\/* Add our header *\/
\nigmp = skb_put(skb, sizeof(struct igmphdr));
\nigmp->type = assert;
\nmsg->im_msgtype = assert;
\nigmp->code = 0;
\nip_hdr(skb)->tot_len = htons(skb->len);\/* Fix the length *\/
\nskb->transport_header = skb->network_header;
\n}<\/p>\nrcu_read_lock();
\nmroute_sk = rcu_dereference(mrt->mroute_sk);
\nif (!mroute_sk) {
\nrcu_read_unlock();
\nkfree_skb(skb);
\nreturn -EINVAL;
\n}<\/p>\nigmpmsg_netlink_event(mrt, skb);<\/p>\n
\/* Deliver to mrouted *\/
\nret = sock_queue_rcv_skb(mroute_sk, skb);
\nrcu_read_unlock();
\nif (ret < 0) {
\nnet_warn_ratelimited("mroute: pending queue full, dropping entries\\\\n");
\nkfree_skb(skb);
\n}<\/p>\nreturn ret;
\n}<\/p>\n\/* Queue a packet for resolution. It gets locked cache entry! *\/
\nstatic int ipmr_cache_unresolved(struct mr_table *mrt, vifi_t vifi,
\n struct sk_buff *skb, struct net_device *dev)
\n{
\nconst struct iphdr *iph = ip_hdr(skb);
\nstruct mfc_cache *c;
\nbool found = false;
\nint err;<\/p>\nspin_lock_bh(&mfc_unres_lock);
\nlist_for_each_entry(c, &mrt->mfc_unres_queue, _c.list) {
\nif (c->mfc_mcastgrp == iph->daddr &&
\n c->mfc_origin == iph->saddr) {
\nfound = true;
\nbreak;
\n}
\n}<\/p>\nif (!found) {
\n\/* Create a new entry if allowable *\/
\nif (atomic_read(&mrt->cache_resolve_queue_len) >= 10 ||
\n (c = ipmr_cache_alloc_unres()) == NULL) {
\nspin_unlock_bh(&mfc_unres_lock);<\/p>\nkfree_skb(skb);
\nreturn -ENOBUFS;
\n}<\/p>\n\/* Fill in the new cache entry *\/
\nc->_c.mfc_parent = -1;
\nc->mfc_origin= iph->saddr;
\nc->mfc_mcastgrp= iph->daddr;<\/p>\n\/* Reflect first query at mrouted. *\/
\nerr = ipmr_cache_report(mrt, skb, vifi, IGMPMSG_NOCACHE);<\/p>\nif (err < 0) {
\n\/* If the report failed throw the cache entry
\n out – Brad Parker
\n *\/
\nspin_unlock_bh(&mfc_unres_lock);<\/p>\nipmr_cache_free(c);
\nkfree_skb(skb);
\nreturn err;
\n}<\/p>\natomic_inc(&mrt->cache_resolve_queue_len);
\nlist_add(&c->_c.list, &mrt->mfc_unres_queue);
\nmroute_netlink_event(mrt, c, RTM_NEWROUTE);<\/p>\nif (atomic_read(&mrt->cache_resolve_queue_len) == 1)
\nmod_timer(&mrt->ipmr_expire_timer,
\n c->_c.mfc_un.unres.expires);
\n}<\/p>\n\/* See if we can append the packet *\/
\nif (c->_c.mfc_un.unres.unresolved.qlen > 3) {
\nkfree_skb(skb);
\nerr = -ENOBUFS;
\n} else {
\nif (dev) {
\nskb->dev = dev;
\nskb->skb_iif = dev->ifindex;
\n}
\nskb_queue_tail(&c->_c.mfc_un.unres.unresolved, skb);
\nerr = 0;
\n}<\/p>\nspin_unlock_bh(&mfc_unres_lock);
\nreturn err;
\n}<\/p>\n\/* MFC cache manipulation by user space mroute daemon *\/<\/p>\n
static int ipmr_mfc_delete(struct mr_table *mrt, struct mfcctl *mfc, int parent)
\n{
\nstruct net *net = read_pnet(&mrt->net);
\nstruct mfc_cache *c;<\/p>\n\/* The entries are added\/deleted only under RTNL *\/
\nrcu_read_lock();
\nc = ipmr_cache_find_parent(mrt, mfc->mfcc_origin.s_addr,
\n mfc->mfcc_mcastgrp.s_addr, parent);
\nrcu_read_unlock();
\nif (!c)
\nreturn -ENOENT;
\nrhltable_remove(&mrt->mfc_hash, &c->_c.mnode, ipmr_rht_params);
\nlist_del_rcu(&c->_c.list);
\ncall_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_DEL, c, mrt->id);
\nmroute_netlink_event(mrt, c, RTM_DELROUTE);
\nmr_cache_put(&c->_c);<\/p>\nreturn 0;
\n}<\/p>\nstatic int ipmr_mfc_add(struct net *net, struct mr_table *mrt,
\nstruct mfcctl *mfc, int mrtsock, int parent)
\n{
\nstruct mfc_cache *uc, *c;
\nstruct mr_mfc *_uc;
\nbool found;
\nint ret;<\/p>\nif (mfc->mfcc_parent >= MAXVIFS)
\nreturn -ENFILE;<\/p>\n\/* The entries are added\/deleted only under RTNL *\/
\nrcu_read_lock();
\nc = ipmr_cache_find_parent(mrt, mfc->mfcc_origin.s_addr,
\n mfc->mfcc_mcastgrp.s_addr, parent);
\nrcu_read_unlock();
\nif (c) {
\nwrite_lock_bh(&mrt_lock);
\nc->_c.mfc_parent = mfc->mfcc_parent;
\nipmr_update_thresholds(mrt, &c->_c, mfc->mfcc_ttls);
\nif (!mrtsock)
\nc->_c.mfc_flags |= MFC_STATIC;
\nwrite_unlock_bh(&mrt_lock);
\ncall_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_REPLACE, c,
\n mrt->id);
\nmroute_netlink_event(mrt, c, RTM_NEWROUTE);
\nreturn 0;
\n}<\/p>\nif (mfc->mfcc_mcastgrp.s_addr != htonl(INADDR_ANY) &&
\n !ipv4_is_multicast(mfc->mfcc_mcastgrp.s_addr))
\nreturn -EINVAL;<\/p>\nc = ipmr_cache_alloc();
\nif (!c)
\nreturn -ENOMEM;<\/p>\nc->mfc_origin = mfc->mfcc_origin.s_addr;
\nc->mfc_mcastgrp = mfc->mfcc_mcastgrp.s_addr;
\nc->_c.mfc_parent = mfc->mfcc_parent;
\nipmr_update_thresholds(mrt, &c->_c, mfc->mfcc_ttls);
\nif (!mrtsock)
\nc->_c.mfc_flags |= MFC_STATIC;<\/p>\nret = rhltable_insert_key(&mrt->mfc_hash, &c->cmparg, &c->_c.mnode,
\n ipmr_rht_params);
\nif (ret) {
\npr_err("ipmr: rhtable insert error %d\\\\n", ret);
\nipmr_cache_free(c);
\nreturn ret;
\n}
\nlist_add_tail_rcu(&c->_c.list, &mrt->mfc_cache_list);
\n\/* Check to see if we resolved a queued list. If so we
\n * need to send on the frames and tidy up.
\n *\/
\nfound = false;
\nspin_lock_bh(&mfc_unres_lock);
\nlist_for_each_entry(_uc, &mrt->mfc_unres_queue, list) {
\nuc = (struct mfc_cache *)_uc;
\nif (uc->mfc_origin == c->mfc_origin &&
\n uc->mfc_mcastgrp == c->mfc_mcastgrp) {
\nlist_del(&_uc->list);
\natomic_dec(&mrt->cache_resolve_queue_len);
\nfound = true;
\nbreak;
\n}
\n}
\nif (list_empty(&mrt->mfc_unres_queue))
\ndel_timer(&mrt->ipmr_expire_timer);
\nspin_unlock_bh(&mfc_unres_lock);<\/p>\nif (found) {
\nipmr_cache_resolve(net, mrt, uc, c);
\nipmr_cache_free(uc);
\n}
\ncall_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_ADD, c, mrt->id);
\nmroute_netlink_event(mrt, c, RTM_NEWROUTE);
\nreturn 0;
\n}<\/p>\n\/* Close the multicast socket, and clear the vif tables etc *\/
\nstatic void mroute_clean_tables(struct mr_table *mrt, bool all)
\n{
\nstruct net *net = read_pnet(&mrt->net);
\nstruct mr_mfc *c, *tmp;
\nstruct mfc_cache *cache;
\nLIST_HEAD(list);
\nint i;<\/p>\n\/* Shut down all active vif entries *\/
\nfor (i = 0; i < mrt->maxvif; i++) {
\nif (!all && (mrt->vif_table[i].flags & VIFF_STATIC))
\ncontinue;
\nvif_delete(mrt, i, 0, &list);
\n}
\nunregister_netdevice_many(&list);<\/p>\n\/* Wipe the cache *\/
\nlist_for_each_entry_safe(c, tmp, &mrt->mfc_cache_list, list) {
\nif (!all && (c->mfc_flags & MFC_STATIC))
\ncontinue;
\nrhltable_remove(&mrt->mfc_hash, &c->mnode, ipmr_rht_params);
\nlist_del_rcu(&c->list);
\ncache = (struct mfc_cache *)c;
\ncall_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_DEL, cache,
\n mrt->id);
\nmroute_netlink_event(mrt, cache, RTM_DELROUTE);
\nmr_cache_put(c);
\n}<\/p>\nif (atomic_read(&mrt->cache_resolve_queue_len) != 0) {
\nspin_lock_bh(&mfc_unres_lock);
\nlist_for_each_entry_safe(c, tmp, &mrt->mfc_unres_queue, list) {
\nlist_del(&c->list);
\ncache = (struct mfc_cache *)c;
\nmroute_netlink_event(mrt, cache, RTM_DELROUTE);
\nipmr_destroy_unres(mrt, cache);
\n}
\nspin_unlock_bh(&mfc_unres_lock);
\n}
\n}<\/p>\n\/* called from ip_ra_control(), before an RCU grace period,
\n * we dont need to call synchronize_rcu() here
\n *\/
\nstatic void mrtsock_destruct(struct sock *sk)
\n{
\nstruct net *net = sock_net(sk);
\nstruct mr_table *mrt;<\/p>\nrtnl_lock();
\nipmr_for_each_table(mrt, net) {
\nif (sk == rtnl_dereference(mrt->mroute_sk)) {
\nIPV4_DEVCONF_ALL(net, MC_FORWARDING)–;
\ninet_netconf_notify_devconf(net, RTM_NEWNETCONF,
\n NETCONFA_MC_FORWARDING,
\n NETCONFA_IFINDEX_ALL,
\n net->ipv4.devconf_all);
\nRCU_INIT_POINTER(mrt->mroute_sk, NULL);
\nmroute_clean_tables(mrt, false);
\n}
\n}
\nrtnl_unlock();
\n}<\/p>\n\/* Socket options and virtual interface manipulation. The whole
\n * virtual interface system is a complete heap, but unfortunately
\n * that's how BSD mrouted happens to think. Maybe one day with a proper
\n * MOSPF\/PIM router set up we can clean this up.
\n *\/<\/p>\nint ip_mroute_setsockopt(struct sock *sk, int optname, char __user *optval,
\n unsigned int optlen)
\n{
\nstruct net *net = sock_net(sk);
\nint val, ret = 0, parent = 0;
\nstruct mr_table *mrt;
\nstruct vifctl vif;
\nstruct mfcctl mfc;
\nbool do_wrvifwhole;
\nu32 uval;<\/p>\n\/* There's one exception to the lock – MRT_DONE which needs to unlock *\/
\nrtnl_lock();
\nif (sk->sk_type != SOCK_RAW ||
\n inet_sk(sk)->inet_num != IPPROTO_IGMP) {
\nret = -EOPNOTSUPP;
\ngoto out_unlock;
\n}<\/p>\nmrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
\nif (!mrt) {
\nret = -ENOENT;
\ngoto out_unlock;
\n}
\nif (optname != MRT_INIT) {
\nif (sk != rcu_access_pointer(mrt->mroute_sk) &&
\n !ns_capable(net->user_ns, CAP_NET_ADMIN)) {
\nret = -EACCES;
\ngoto out_unlock;
\n}
\n}<\/p>\nswitch (optname) {
\ncase MRT_INIT:
\nif (optlen != sizeof(int)) {
\nret = -EINVAL;
\nbreak;
\n}
\nif (rtnl_dereference(mrt->mroute_sk)) {
\nret = -EADDRINUSE;
\nbreak;
\n}<\/p>\nret = ip_ra_control(sk, 1, mrtsock_destruct);
\nif (ret == 0) {
\nrcu_assign_pointer(mrt->mroute_sk, sk);
\nIPV4_DEVCONF_ALL(net, MC_FORWARDING)++;
\ninet_netconf_notify_devconf(net, RTM_NEWNETCONF,
\n NETCONFA_MC_FORWARDING,
\n NETCONFA_IFINDEX_ALL,
\n net->ipv4.devconf_all);
\n}
\nbreak;
\ncase MRT_DONE:
\nif (sk != rcu_access_pointer(mrt->mroute_sk)) {
\nret = -EACCES;
\n} else {
\n\/* We need to unlock here because mrtsock_destruct takes
\n * care of rtnl itself and we can't change that due to
\n * the IP_ROUTER_ALERT setsockopt which runs without it.
\n *\/
\nrtnl_unlock();
\nret = ip_ra_control(sk, 0, NULL);
\ngoto out;
\n}
\nbreak;
\ncase MRT_ADD_VIF:
\ncase MRT_DEL_VIF:
\nif (optlen != sizeof(vif)) {
\nret = -EINVAL;
\nbreak;
\n}
\nif (copy_from_user(&vif, optval, sizeof(vif))) {
\nret = -EFAULT;
\nbreak;
\n}
\nif (vif.vifc_vifi >= MAXVIFS) {
\nret = -ENFILE;
\nbreak;
\n}
\nif (optname == MRT_ADD_VIF) {
\nret = vif_add(net, mrt, &vif,
\n sk == rtnl_dereference(mrt->mroute_sk));
\n} else {
\nret = vif_delete(mrt, vif.vifc_vifi, 0, NULL);
\n}
\nbreak;
\n\/* Manipulate the forwarding caches. These live
\n * in a sort of kernel\/user symbiosis.
\n *\/
\ncase MRT_ADD_MFC:
\ncase MRT_DEL_MFC:
\nparent = -1;
\n\/* fall through *\/
\ncase MRT_ADD_MFC_PROXY:
\ncase MRT_DEL_MFC_PROXY:
\nif (optlen != sizeof(mfc)) {
\nret = -EINVAL;
\nbreak;
\n}
\nif (copy_from_user(&mfc, optval, sizeof(mfc))) {
\nret = -EFAULT;
\nbreak;
\n}
\nif (parent == 0)
\nparent = mfc.mfcc_parent;
\nif (optname == MRT_DEL_MFC || optname == MRT_DEL_MFC_PROXY)
\nret = ipmr_mfc_delete(mrt, &mfc, parent);
\nelse
\nret = ipmr_mfc_add(net, mrt, &mfc,
\n sk == rtnl_dereference(mrt->mroute_sk),
\n parent);
\nbreak;
\n\/* Control PIM assert. *\/
\ncase MRT_ASSERT:
\nif (optlen != sizeof(val)) {
\nret = -EINVAL;
\nbreak;
\n}
\nif (get_user(val, (int __user *)optval)) {
\nret = -EFAULT;
\nbreak;
\n}
\nmrt->mroute_do_assert = val;
\nbreak;
\ncase MRT_PIM:
\nif (!ipmr_pimsm_enabled()) {
\nret = -ENOPROTOOPT;
\nbreak;
\n}
\nif (optlen != sizeof(val)) {
\nret = -EINVAL;
\nbreak;
\n}
\nif (get_user(val, (int __user *)optval)) {
\nret = -EFAULT;
\nbreak;
\n}<\/p>\ndo_wrvifwhole = (val == IGMPMSG_WRVIFWHOLE);
\nval = !!val;
\nif (val != mrt->mroute_do_pim) {
\nmrt->mroute_do_pim = val;
\nmrt->mroute_do_assert = val;
\nmrt->mroute_do_wrvifwhole = do_wrvifwhole;
\n}
\nbreak;
\ncase MRT_TABLE:
\nif (!IS_BUILTIN(CONFIG_IP_MROUTE_MULTIPLE_TABLES)) {
\nret = -ENOPROTOOPT;
\nbreak;
\n}
\nif (optlen != sizeof(uval)) {
\nret = -EINVAL;
\nbreak;
\n}
\nif (get_user(uval, (u32 __user *)optval)) {
\nret = -EFAULT;
\nbreak;
\n}<\/p>\nif (sk == rtnl_dereference(mrt->mroute_sk)) {
\nret = -EBUSY;
\n} else {
\nmrt = ipmr_new_table(net, uval);
\nif (IS_ERR(mrt))
\nret = PTR_ERR(mrt);
\nelse
\nraw_sk(sk)->ipmr_table = uval;
\n}
\nbreak;
\n\/* Spurious command, or MRT_VERSION which you cannot set. *\/
\ndefault:
\nret = -ENOPROTOOPT;
\n}
\nout_unlock:
\nrtnl_unlock();
\nout:
\nreturn ret;
\n}<\/p>\n\/* Getsock opt support for the multicast routing system. *\/
\nint ip_mroute_getsockopt(struct sock *sk, int optname, char __user *optval, int __user *optlen)
\n{
\nint olr;
\nint val;
\nstruct net *net = sock_net(sk);
\nstruct mr_table *mrt;<\/p>\nif (sk->sk_type != SOCK_RAW ||
\n inet_sk(sk)->inet_num != IPPROTO_IGMP)
\nreturn -EOPNOTSUPP;<\/p>\nmrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
\nif (!mrt)
\nreturn -ENOENT;<\/p>\nswitch (optname) {
\ncase MRT_VERSION:
\nval = 0x0305;
\nbreak;
\ncase MRT_PIM:
\nif (!ipmr_pimsm_enabled())
\nreturn -ENOPROTOOPT;
\nval = mrt->mroute_do_pim;
\nbreak;
\ncase MRT_ASSERT:
\nval = mrt->mroute_do_assert;
\nbreak;
\ndefault:
\nreturn -ENOPROTOOPT;
\n}<\/p>\nif (get_user(olr, optlen))
\nreturn -EFAULT;
\nolr = min_t(unsigned int, olr, sizeof(int));
\nif (olr < 0)
\nreturn -EINVAL;
\nif (put_user(olr, optlen))
\nreturn -EFAULT;
\nif (copy_to_user(optval, &val, olr))
\nreturn -EFAULT;
\nreturn 0;
\n}<\/p>\n\/* The IP multicast ioctl support routines. *\/
\nint ipmr_ioctl(struct sock *sk, int cmd, void __user *arg)
\n{
\nstruct sioc_sg_req sr;
\nstruct sioc_vif_req vr;
\nstruct vif_device *vif;
\nstruct mfc_cache *c;
\nstruct net *net = sock_net(sk);
\nstruct mr_table *mrt;<\/p>\nmrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
\nif (!mrt)
\nreturn -ENOENT;<\/p>\nswitch (cmd) {
\ncase SIOCGETVIFCNT:
\nif (copy_from_user(&vr, arg, sizeof(vr)))
\nreturn -EFAULT;
\nif (vr.vifi >= mrt->maxvif)
\nreturn -EINVAL;
\nvr.vifi = array_index_nospec(vr.vifi, mrt->maxvif);
\nread_lock(&mrt_lock);
\nvif = &mrt->vif_table[vr.vifi];
\nif (VIF_EXISTS(mrt, vr.vifi)) {
\nvr.icount = vif->pkt_in;
\nvr.ocount = vif->pkt_out;
\nvr.ibytes = vif->bytes_in;
\nvr.obytes = vif->bytes_out;
\nread_unlock(&mrt_lock);<\/p>\nif (copy_to_user(arg, &vr, sizeof(vr)))
\nreturn -EFAULT;
\nreturn 0;
\n}
\nread_unlock(&mrt_lock);
\nreturn -EADDRNOTAVAIL;
\ncase SIOCGETSGCNT:
\nif (copy_from_user(&sr, arg, sizeof(sr)))
\nreturn -EFAULT;<\/p>\nrcu_read_lock();
\nc = ipmr_cache_find(mrt, sr.src.s_addr, sr.grp.s_addr);
\nif (c) {
\nsr.pktcnt = c->_c.mfc_un.res.pkt;
\nsr.bytecnt = c->_c.mfc_un.res.bytes;
\nsr.wrong_if = c->_c.mfc_un.res.wrong_if;
\nrcu_read_unlock();<\/p>\nif (copy_to_user(arg, &sr, sizeof(sr)))
\nreturn -EFAULT;
\nreturn 0;
\n}
\nrcu_read_unlock();
\nreturn -EADDRNOTAVAIL;
\ndefault:
\nreturn -ENOIOCTLCMD;
\n}
\n}<\/p>\n#ifdef CONFIG_COMPAT
\nstruct compat_sioc_sg_req {
\nstruct in_addr src;
\nstruct in_addr grp;
\ncompat_ulong_t pktcnt;
\ncompat_ulong_t bytecnt;
\ncompat_ulong_t wrong_if;
\n};<\/p>\nstruct compat_sioc_vif_req {
\nvifi_tvifi;\/* Which iface *\/
\ncompat_ulong_t icount;
\ncompat_ulong_t ocount;
\ncompat_ulong_t ibytes;
\ncompat_ulong_t obytes;
\n};<\/p>\nint ipmr_compat_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
\n{
\nstruct compat_sioc_sg_req sr;
\nstruct compat_sioc_vif_req vr;
\nstruct vif_device *vif;
\nstruct mfc_cache *c;
\nstruct net *net = sock_net(sk);
\nstruct mr_table *mrt;<\/p>\nmrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
\nif (!mrt)
\nreturn -ENOENT;<\/p>\nswitch (cmd) {
\ncase SIOCGETVIFCNT:
\nif (copy_from_user(&vr, arg, sizeof(vr)))
\nreturn -EFAULT;
\nif (vr.vifi >= mrt->maxvif)
\nreturn -EINVAL;
\nvr.vifi = array_index_nospec(vr.vifi, mrt->maxvif);
\nread_lock(&mrt_lock);
\nvif = &mrt->vif_table[vr.vifi];
\nif (VIF_EXISTS(mrt, vr.vifi)) {
\nvr.icount = vif->pkt_in;
\nvr.ocount = vif->pkt_out;
\nvr.ibytes = vif->bytes_in;
\nvr.obytes = vif->bytes_out;
\nread_unlock(&mrt_lock);<\/p>\nif (copy_to_user(arg, &vr, sizeof(vr)))
\nreturn -EFAULT;
\nreturn 0;
\n}
\nread_unlock(&mrt_lock);
\nreturn -EADDRNOTAVAIL;
\ncase SIOCGETSGCNT:
\nif (copy_from_user(&sr, arg, sizeof(sr)))
\nreturn -EFAULT;<\/p>\nrcu_read_lock();
\nc = ipmr_cache_find(mrt, sr.src.s_addr, sr.grp.s_addr);
\nif (c) {
\nsr.pktcnt = c->_c.mfc_un.res.pkt;
\nsr.bytecnt = c->_c.mfc_un.res.bytes;
\nsr.wrong_if = c->_c.mfc_un.res.wrong_if;
\nrcu_read_unlock();<\/p>\nif (copy_to_user(arg, &sr, sizeof(sr)))
\nreturn -EFAULT;
\nreturn 0;
\n}
\nrcu_read_unlock();
\nreturn -EADDRNOTAVAIL;
\ndefault:
\nreturn -ENOIOCTLCMD;
\n}
\n}
\n#endif<\/p>\nstatic int ipmr_device_event(struct notifier_block *this, unsigned long event, void *ptr)
\n{
\nstruct net_device *dev = netdev_notifier_info_to_dev(ptr);
\nstruct net *net = dev_net(dev);
\nstruct mr_table *mrt;
\nstruct vif_device *v;
\nint ct;<\/p>\nif (event != NETDEV_UNREGISTER)
\nreturn NOTIFY_DONE;<\/p>\nipmr_for_each_table(mrt, net) {
\nv = &mrt->vif_table[0];
\nfor (ct = 0; ct < mrt->maxvif; ct++, v++) {
\nif (v->dev == dev)
\nvif_delete(mrt, ct, 1, NULL);
\n}
\n}
\nreturn NOTIFY_DONE;
\n}<\/p>\nstatic struct notifier_block ip_mr_notifier = {
\n.notifier_call = ipmr_device_event,
\n};<\/p>\n\/* Encapsulate a packet by attaching a valid IPIP header to it.
\n * This avoids tunnel drivers and other mess and gives us the speed so
\n * important for multicast video.
\n *\/
\nstatic void ip_encap(struct net *net, struct sk_buff *skb,
\n __be32 saddr, __be32 daddr)
\n{
\nstruct iphdr *iph;
\nconst struct iphdr *old_iph = ip_hdr(skb);<\/p>\nskb_push(skb, sizeof(struct iphdr));
\nskb->transport_header = skb->network_header;
\nskb_reset_network_header(skb);
\niph = ip_hdr(skb);<\/p>\niph->version=4;
\niph->tos=old_iph->tos;
\niph->ttl=old_iph->ttl;
\niph->frag_off=0;
\niph->daddr=daddr;
\niph->saddr=saddr;
\niph->protocol=IPPROTO_IPIP;
\niph->ihl=5;
\niph->tot_len=htons(skb->len);
\nip_select_ident(net, skb, NULL);
\nip_send_check(iph);<\/p>\nmemset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
\nnf_reset(skb);
\n}<\/p>\nstatic inline int ipmr_forward_finish(struct net *net, struct sock *sk,
\n struct sk_buff *skb)
\n{
\nstruct ip_options *opt = &(IPCB(skb)->opt);<\/p>\nIP_INC_STATS(net, IPSTATS_MIB_OUTFORWDATAGRAMS);
\nIP_ADD_STATS(net, IPSTATS_MIB_OUTOCTETS, skb->len);<\/p>\nif (unlikely(opt->optlen))
\nip_forward_options(skb);<\/p>\nreturn dst_output(net, sk, skb);
\n}<\/p>\n#ifdef CONFIG_NET_SWITCHDEV
\nstatic bool ipmr_forward_offloaded(struct sk_buff *skb, struct mr_table *mrt,
\n int in_vifi, int out_vifi)
\n{
\nstruct vif_device *out_vif = &mrt->vif_table[out_vifi];
\nstruct vif_device *in_vif = &mrt->vif_table[in_vifi];<\/p>\nif (!skb->offload_mr_fwd_mark)
\nreturn false;
\nif (!out_vif->dev_parent_id.id_len || !in_vif->dev_parent_id.id_len)
\nreturn false;
\nreturn netdev_phys_item_id_same(&out_vif->dev_parent_id,
\n&in_vif->dev_parent_id);
\n}
\n#else
\nstatic bool ipmr_forward_offloaded(struct sk_buff *skb, struct mr_table *mrt,
\n int in_vifi, int out_vifi)
\n{
\nreturn false;
\n}
\n#endif<\/p>\n\/* Processing handlers for ipmr_forward *\/<\/p>\n
static void ipmr_queue_xmit(struct net *net, struct mr_table *mrt,
\n int in_vifi, struct sk_buff *skb,
\n struct mfc_cache *c, int vifi)
\n{
\nconst struct iphdr *iph = ip_hdr(skb);
\nstruct vif_device *vif = &mrt->vif_table[vifi];
\nstruct net_device *dev;
\nstruct rtable *rt;
\nstruct flowi4 fl4;
\nint encap = 0;<\/p>\nif (!vif->dev)
\ngoto out_free;<\/p>\nif (vif->flags & VIFF_REGISTER) {
\nvif->pkt_out++;
\nvif->bytes_out += skb->len;
\nvif->dev->stats.tx_bytes += skb->len;
\nvif->dev->stats.tx_packets++;
\nipmr_cache_report(mrt, skb, vifi, IGMPMSG_WHOLEPKT);
\ngoto out_free;
\n}<\/p>\nif (ipmr_forward_offloaded(skb, mrt, in_vifi, vifi))
\ngoto out_free;<\/p>\nif (vif->flags & VIFF_TUNNEL) {
\nrt = ip_route_output_ports(net, &fl4, NULL,
\n vif->remote, vif->local,
\n 0, 0,
\n IPPROTO_IPIP,
\n RT_TOS(iph->tos), vif->link);
\nif (IS_ERR(rt))
\ngoto out_free;
\nencap = sizeof(struct iphdr);
\n} else {
\nrt = ip_route_output_ports(net, &fl4, NULL, iph->daddr, 0,
\n 0, 0,
\n IPPROTO_IPIP,
\n RT_TOS(iph->tos), vif->link);
\nif (IS_ERR(rt))
\ngoto out_free;
\n}<\/p>\ndev = rt->dst.dev;<\/p>\n
if (skb->len+encap > dst_mtu(&rt->dst) && (ntohs(iph->frag_off) & IP_DF)) {
\n\/* Do not fragment multicasts. Alas, IPv4 does not
\n * allow to send ICMP, so that packets will disappear
\n * to blackhole.
\n *\/
\nIP_INC_STATS(net, IPSTATS_MIB_FRAGFAILS);
\nip_rt_put(rt);
\ngoto out_free;
\n}<\/p>\nencap += LL_RESERVED_SPACE(dev) + rt->dst.header_len;<\/p>\n
if (skb_cow(skb, encap)) {
\nip_rt_put(rt);
\ngoto out_free;
\n}<\/p>\nvif->pkt_out++;
\nvif->bytes_out += skb->len;<\/p>\nskb_dst_drop(skb);
\nskb_dst_set(skb, &rt->dst);
\nip_decrease_ttl(ip_hdr(skb));<\/p>\n\/* FIXME: forward and output firewalls used to be called here.
\n * What do we do with netfilter? — RR
\n *\/
\nif (vif->flags & VIFF_TUNNEL) {
\nip_encap(net, skb, vif->local, vif->remote);
\n\/* FIXME: extra output firewall step used to be here. –RR *\/
\nvif->dev->stats.tx_packets++;
\nvif->dev->stats.tx_bytes += skb->len;
\n}<\/p>\nIPCB(skb)->flags |= IPSKB_FORWARDED;<\/p>\n
\/* RFC1584 teaches, that DVMRP\/PIM router must deliver packets locally
\n * not only before forwarding, but after forwarding on all output
\n * interfaces. It is clear, if mrouter runs a multicasting
\n * program, it should receive packets not depending to what interface
\n * program is joined.
\n * If we will not make it, the program will have to join on all
\n * interfaces. On the other hand, multihoming host (or router, but
\n * not mrouter) cannot join to more than one interface – it will
\n * result in receiving multiple packets.
\n *\/
\nNF_HOOK(NFPROTO_IPV4, NF_INET_FORWARD,
\nnet, NULL, skb, skb->dev, dev,
\nipmr_forward_finish);
\nreturn;<\/p>\nout_free:
\nkfree_skb(skb);
\n}<\/p>\nstatic int ipmr_find_vif(struct mr_table *mrt, struct net_device *dev)
\n{
\nint ct;<\/p>\nfor (ct = mrt->maxvif-1; ct >= 0; ct–) {
\nif (mrt->vif_table[ct].dev == dev)
\nbreak;
\n}
\nreturn ct;
\n}<\/p>\n\/* "local" means that we should preserve one skb (for local delivery) *\/
\nstatic void ip_mr_forward(struct net *net, struct mr_table *mrt,
\n struct net_device *dev, struct sk_buff *skb,
\n struct mfc_cache *c, int local)
\n{
\nint true_vifi = ipmr_find_vif(mrt, dev);
\nint psend = -1;
\nint vif, ct;<\/p>\nvif = c->_c.mfc_parent;
\nc->_c.mfc_un.res.pkt++;
\nc->_c.mfc_un.res.bytes += skb->len;
\nc->_c.mfc_un.res.lastuse = jiffies;<\/p>\nif (c->mfc_origin == htonl(INADDR_ANY) && true_vifi >= 0) {
\nstruct mfc_cache *cache_proxy;<\/p>\n\/* For an (*,G) entry, we only check that the incomming
\n * interface is part of the static tree.
\n *\/
\ncache_proxy = mr_mfc_find_any_parent(mrt, vif);
\nif (cache_proxy &&
\n cache_proxy->_c.mfc_un.res.ttls[true_vifi] < 255)
\ngoto forward;
\n}<\/p>\n\/* Wrong interface: drop packet and (maybe) send PIM assert. *\/
\nif (mrt->vif_table[vif].dev != dev) {
\nif (rt_is_output_route(skb_rtable(skb))) {
\n\/* It is our own packet, looped back.
\n * Very complicated situation…
\n *
\n * The best workaround until routing daemons will be
\n * fixed is not to redistribute packet, if it was
\n * send through wrong interface. It means, that
\n * multicast applications WILL NOT work for
\n * (S,G), which have default multicast route pointing
\n * to wrong oif. In any case, it is not a good
\n * idea to use multicasting applications on router.
\n *\/
\ngoto dont_forward;
\n}<\/p>\nc->_c.mfc_un.res.wrong_if++;<\/p>\n
if (true_vifi >= 0 && mrt->mroute_do_assert &&
\n \/* pimsm uses asserts, when switching from RPT to SPT,
\n * so that we cannot check that packet arrived on an oif.
\n * It is bad, but otherwise we would need to move pretty
\n * large chunk of pimd to kernel. Ough… –ANK
\n *\/
\n (mrt->mroute_do_pim ||
\n c->_c.mfc_un.res.ttls[true_vifi] < 255) &&
\n time_after(jiffies,
\n c->_c.mfc_un.res.last_assert +
\n MFC_ASSERT_THRESH)) {
\nc->_c.mfc_un.res.last_assert = jiffies;
\nipmr_cache_report(mrt, skb, true_vifi, IGMPMSG_WRONGVIF);
\nif (mrt->mroute_do_wrvifwhole)
\nipmr_cache_report(mrt, skb, true_vifi,
\n IGMPMSG_WRVIFWHOLE);
\n}
\ngoto dont_forward;
\n}<\/p>\nforward:
\nmrt->vif_table[vif].pkt_in++;
\nmrt->vif_table[vif].bytes_in += skb->len;<\/p>\n\/* Forward the frame *\/
\nif (c->mfc_origin == htonl(INADDR_ANY) &&
\n c->mfc_mcastgrp == htonl(INADDR_ANY)) {
\nif (true_vifi >= 0 &&
\n true_vifi != c->_c.mfc_parent &&
\n ip_hdr(skb)->ttl >
\nc->_c.mfc_un.res.ttls[c->_c.mfc_parent]) {
\n\/* It's an (*,*) entry and the packet is not coming from
\n * the upstream: forward the packet to the upstream
\n * only.
\n *\/
\npsend = c->_c.mfc_parent;
\ngoto last_forward;
\n}
\ngoto dont_forward;
\n}
\nfor (ct = c->_c.mfc_un.res.maxvif – 1;
\n ct >= c->_c.mfc_un.res.minvif; ct–) {
\n\/* For (*,G) entry, don't forward to the incoming interface *\/
\nif ((c->mfc_origin != htonl(INADDR_ANY) ||
\n ct != true_vifi) &&
\n ip_hdr(skb)->ttl > c->_c.mfc_un.res.ttls[ct]) {
\nif (psend != -1) {
\nstruct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);<\/p>\nif (skb2)
\nipmr_queue_xmit(net, mrt, true_vifi,
\nskb2, c, psend);
\n}
\npsend = ct;
\n}
\n}
\nlast_forward:
\nif (psend != -1) {
\nif (local) {
\nstruct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);<\/p>\nif (skb2)
\nipmr_queue_xmit(net, mrt, true_vifi, skb2,
\nc, psend);
\n} else {
\nipmr_queue_xmit(net, mrt, true_vifi, skb, c, psend);
\nreturn;
\n}
\n}<\/p>\ndont_forward:
\nif (!local)
\nkfree_skb(skb);
\n}<\/p>\nstatic struct mr_table *ipmr_rt_fib_lookup(struct net *net, struct sk_buff *skb)
\n{
\nstruct rtable *rt = skb_rtable(skb);
\nstruct iphdr *iph = ip_hdr(skb);
\nstruct flowi4 fl4 = {
\n.daddr = iph->daddr,
\n.saddr = iph->saddr,
\n.flowi4_tos = RT_TOS(iph->tos),
\n.flowi4_oif = (rt_is_output_route(rt) ?
\n skb->dev->ifindex : 0),
\n.flowi4_iif = (rt_is_output_route(rt) ?
\n LOOPBACK_IFINDEX :
\n skb->dev->ifindex),
\n.flowi4_mark = skb->mark,
\n};
\nstruct mr_table *mrt;
\nint err;<\/p>\nerr = ipmr_fib_lookup(net, &fl4, &mrt);
\nif (err)
\nreturn ERR_PTR(err);
\nreturn mrt;
\n}<\/p>\n\/* Multicast packets for forwarding arrive here
\n * Called with rcu_read_lock();
\n *\/
\nint ip_mr_input(struct sk_buff *skb)
\n{
\nstruct mfc_cache *cache;
\nstruct net *net = dev_net(skb->dev);
\nint local = skb_rtable(skb)->rt_flags & RTCF_LOCAL;
\nstruct mr_table *mrt;
\nstruct net_device *dev;<\/p>\n\/* skb->dev passed in is the loX master dev for vrfs.
\n * As there are no vifs associated with loopback devices,
\n * get the proper interface that does have a vif associated with it.
\n *\/
\ndev = skb->dev;
\nif (netif_is_l3_master(skb->dev)) {
\ndev = dev_get_by_index_rcu(net, IPCB(skb)->iif);
\nif (!dev) {
\nkfree_skb(skb);
\nreturn -ENODEV;
\n}
\n}<\/p>\n\/* Packet is looped back after forward, it should not be
\n * forwarded second time, but still can be delivered locally.
\n *\/
\nif (IPCB(skb)->flags & IPSKB_FORWARDED)
\ngoto dont_forward;<\/p>\nmrt = ipmr_rt_fib_lookup(net, skb);
\nif (IS_ERR(mrt)) {
\nkfree_skb(skb);
\nreturn PTR_ERR(mrt);
\n}
\nif (!local) {
\nif (IPCB(skb)->opt.router_alert) {
\nif (ip_call_ra_chain(skb))
\nreturn 0;
\n} else if (ip_hdr(skb)->protocol == IPPROTO_IGMP) {
\n\/* IGMPv1 (and broken IGMPv2 implementations sort of
\n * Cisco IOS <= 11.2(8)) do not put router alert
\n * option to IGMP packets destined to routable
\n * groups. It is very bad, because it means
\n * that we can forward NO IGMP messages.
\n *\/
\nstruct sock *mroute_sk;<\/p>\nmroute_sk = rcu_dereference(mrt->mroute_sk);
\nif (mroute_sk) {
\nnf_reset(skb);
\nraw_rcv(mroute_sk, skb);
\nreturn 0;
\n}
\n }
\n}<\/p>\n\/* already under rcu_read_lock() *\/
\ncache = ipmr_cache_find(mrt, ip_hdr(skb)->saddr, ip_hdr(skb)->daddr);
\nif (!cache) {
\nint vif = ipmr_find_vif(mrt, dev);<\/p>\nif (vif >= 0)
\ncache = ipmr_cache_find_any(mrt, ip_hdr(skb)->daddr,
\n vif);
\n}<\/p>\n\/* No usable cache entry *\/
\nif (!cache) {
\nint vif;<\/p>\nif (local) {
\nstruct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
\nip_local_deliver(skb);
\nif (!skb2)
\nreturn -ENOBUFS;
\nskb = skb2;
\n}<\/p>\nread_lock(&mrt_lock);
\nvif = ipmr_find_vif(mrt, dev);
\nif (vif >= 0) {
\nint err2 = ipmr_cache_unresolved(mrt, vif, skb, dev);
\nread_unlock(&mrt_lock);<\/p>\nreturn err2;
\n}
\nread_unlock(&mrt_lock);
\nkfree_skb(skb);
\nreturn -ENODEV;
\n}<\/p>\nread_lock(&mrt_lock);
\nip_mr_forward(net, mrt, dev, skb, cache, local);
\nread_unlock(&mrt_lock);<\/p>\nif (local)
\nreturn ip_local_deliver(skb);<\/p>\nreturn 0;<\/p>\n
dont_forward:
\nif (local)
\nreturn ip_local_deliver(skb);
\nkfree_skb(skb);
\nreturn 0;
\n}<\/p>\n#ifdef CONFIG_IP_PIMSM_V1
\n\/* Handle IGMP messages of PIMv1 *\/
\nint pim_rcv_v1(struct sk_buff *skb)
\n{
\nstruct igmphdr *pim;
\nstruct net *net = dev_net(skb->dev);
\nstruct mr_table *mrt;<\/p>\nif (!pskb_may_pull(skb, sizeof(*pim) + sizeof(struct iphdr)))
\ngoto drop;<\/p>\npim = igmp_hdr(skb);<\/p>\n
mrt = ipmr_rt_fib_lookup(net, skb);
\nif (IS_ERR(mrt))
\ngoto drop;
\nif (!mrt->mroute_do_pim ||
\n pim->group != PIM_V1_VERSION || pim->code != PIM_V1_REGISTER)
\ngoto drop;<\/p>\nif (__pim_rcv(mrt, skb, sizeof(*pim))) {
\ndrop:
\nkfree_skb(skb);
\n}
\nreturn 0;
\n}
\n#endif<\/p>\n#ifdef CONFIG_IP_PIMSM_V2
\nstatic int pim_rcv(struct sk_buff *skb)
\n{
\nstruct pimreghdr *pim;
\nstruct net *net = dev_net(skb->dev);
\nstruct mr_table *mrt;<\/p>\nif (!pskb_may_pull(skb, sizeof(*pim) + sizeof(struct iphdr)))
\ngoto drop;<\/p>\npim = (struct pimreghdr *)skb_transport_header(skb);
\nif (pim->type != ((PIM_VERSION << 4) | (PIM_TYPE_REGISTER)) ||
\n (pim->flags & PIM_NULL_REGISTER) ||
\n (ip_compute_csum((void *)pim, sizeof(*pim)) != 0 &&
\n csum_fold(skb_checksum(skb, 0, skb->len, 0))))
\ngoto drop;<\/p>\nmrt = ipmr_rt_fib_lookup(net, skb);
\nif (IS_ERR(mrt))
\ngoto drop;
\nif (__pim_rcv(mrt, skb, sizeof(*pim))) {
\ndrop:
\nkfree_skb(skb);
\n}
\nreturn 0;
\n}
\n#endif<\/p>\nint ipmr_get_route(struct net *net, struct sk_buff *skb,
\n __be32 saddr, __be32 daddr,
\n struct rtmsg *rtm, u32 portid)
\n{
\nstruct mfc_cache *cache;
\nstruct mr_table *mrt;
\nint err;<\/p>\nmrt = ipmr_get_table(net, RT_TABLE_DEFAULT);
\nif (!mrt)
\nreturn -ENOENT;<\/p>\nrcu_read_lock();
\ncache = ipmr_cache_find(mrt, saddr, daddr);
\nif (!cache && skb->dev) {
\nint vif = ipmr_find_vif(mrt, skb->dev);<\/p>\nif (vif >= 0)
\ncache = ipmr_cache_find_any(mrt, daddr, vif);
\n}
\nif (!cache) {
\nstruct sk_buff *skb2;
\nstruct iphdr *iph;
\nstruct net_device *dev;
\nint vif = -1;<\/p>\ndev = skb->dev;
\nread_lock(&mrt_lock);
\nif (dev)
\nvif = ipmr_find_vif(mrt, dev);
\nif (vif < 0) {
\nread_unlock(&mrt_lock);
\nrcu_read_unlock();
\nreturn -ENODEV;
\n}
\nskb2 = skb_clone(skb, GFP_ATOMIC);
\nif (!skb2) {
\nread_unlock(&mrt_lock);
\nrcu_read_unlock();
\nreturn -ENOMEM;
\n}<\/p>\nNETLINK_CB(skb2).portid = portid;
\nskb_push(skb2, sizeof(struct iphdr));
\nskb_reset_network_header(skb2);
\niph = ip_hdr(skb2);
\niph->ihl = sizeof(struct iphdr) >> 2;
\niph->saddr = saddr;
\niph->daddr = daddr;
\niph->version = 0;
\nerr = ipmr_cache_unresolved(mrt, vif, skb2, dev);
\nread_unlock(&mrt_lock);
\nrcu_read_unlock();
\nreturn err;
\n}<\/p>\nread_lock(&mrt_lock);
\nerr = mr_fill_mroute(mrt, skb, &cache->_c, rtm);
\nread_unlock(&mrt_lock);
\nrcu_read_unlock();
\nreturn err;
\n}<\/p>\nstatic int ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
\n u32 portid, u32 seq, struct mfc_cache *c, int cmd,
\n int flags)
\n{
\nstruct nlmsghdr *nlh;
\nstruct rtmsg *rtm;
\nint err;<\/p>\nnlh = nlmsg_put(skb, portid, seq, cmd, sizeof(*rtm), flags);
\nif (!nlh)
\nreturn -EMSGSIZE;<\/p>\nrtm = nlmsg_data(nlh);
\nrtm->rtm_family = RTNL_FAMILY_IPMR;
\nrtm->rtm_dst_len = 32;
\nrtm->rtm_src_len = 32;
\nrtm->rtm_tos = 0;
\nrtm->rtm_table = mrt->id;
\nif (nla_put_u32(skb, RTA_TABLE, mrt->id))
\ngoto nla_put_failure;
\nrtm->rtm_type = RTN_MULTICAST;
\nrtm->rtm_scope = RT_SCOPE_UNIVERSE;
\nif (c->_c.mfc_flags & MFC_STATIC)
\nrtm->rtm_protocol = RTPROT_STATIC;
\nelse
\nrtm->rtm_protocol = RTPROT_MROUTED;
\nrtm->rtm_flags = 0;<\/p>\nif (nla_put_in_addr(skb, RTA_SRC, c->mfc_origin) ||
\n nla_put_in_addr(skb, RTA_DST, c->mfc_mcastgrp))
\ngoto nla_put_failure;
\nerr = mr_fill_mroute(mrt, skb, &c->_c, rtm);
\n\/* do not break the dump if cache is unresolved *\/
\nif (err < 0 && err != -ENOENT)
\ngoto nla_put_failure;<\/p>\nnlmsg_end(skb, nlh);
\nreturn 0;<\/p>\nnla_put_failure:
\nnlmsg_cancel(skb, nlh);
\nreturn -EMSGSIZE;
\n}<\/p>\nstatic int _ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
\n u32 portid, u32 seq, struct mr_mfc *c, int cmd,
\n int flags)
\n{
\nreturn ipmr_fill_mroute(mrt, skb, portid, seq, (struct mfc_cache *)c,
\ncmd, flags);
\n}<\/p>\nstatic size_t mroute_msgsize(bool unresolved, int maxvif)
\n{
\nsize_t len =
\nNLMSG_ALIGN(sizeof(struct rtmsg))
\n+ nla_total_size(4)\/* RTA_TABLE *\/
\n+ nla_total_size(4)\/* RTA_SRC *\/
\n+ nla_total_size(4)\/* RTA_DST *\/
\n;<\/p>\nif (!unresolved)
\nlen = len
\n + nla_total_size(4)\/* RTA_IIF *\/
\n + nla_total_size(0)\/* RTA_MULTIPATH *\/
\n + maxvif * NLA_ALIGN(sizeof(struct rtnexthop))
\n\/* RTA_MFC_STATS *\/
\n + nla_total_size_64bit(sizeof(struct rta_mfc_stats))
\n;<\/p>\nreturn len;
\n}<\/p>\nstatic void mroute_netlink_event(struct mr_table *mrt, struct mfc_cache *mfc,
\n int cmd)
\n{
\nstruct net *net = read_pnet(&mrt->net);
\nstruct sk_buff *skb;
\nint err = -ENOBUFS;<\/p>\nskb = nlmsg_new(mroute_msgsize(mfc->_c.mfc_parent >= MAXVIFS,
\n mrt->maxvif),
\nGFP_ATOMIC);
\nif (!skb)
\ngoto errout;<\/p>\nerr = ipmr_fill_mroute(mrt, skb, 0, 0, mfc, cmd, 0);
\nif (err < 0)
\ngoto errout;<\/p>\nrtnl_notify(skb, net, 0, RTNLGRP_IPV4_MROUTE, NULL, GFP_ATOMIC);
\nreturn;<\/p>\nerrout:
\nkfree_skb(skb);
\nif (err < 0)
\nrtnl_set_sk_err(net, RTNLGRP_IPV4_MROUTE, err);
\n}<\/p>\nstatic size_t igmpmsg_netlink_msgsize(size_t payloadlen)
\n{
\nsize_t len =
\nNLMSG_ALIGN(sizeof(struct rtgenmsg))
\n+ nla_total_size(1)\/* IPMRA_CREPORT_MSGTYPE *\/
\n+ nla_total_size(4)\/* IPMRA_CREPORT_VIF_ID *\/
\n+ nla_total_size(4)\/* IPMRA_CREPORT_SRC_ADDR *\/
\n+ nla_total_size(4)\/* IPMRA_CREPORT_DST_ADDR *\/
\n\/* IPMRA_CREPORT_PKT *\/
\n+ nla_total_size(payloadlen)
\n;<\/p>\nreturn len;
\n}<\/p>\nstatic void igmpmsg_netlink_event(struct mr_table *mrt, struct sk_buff *pkt)
\n{
\nstruct net *net = read_pnet(&mrt->net);
\nstruct nlmsghdr *nlh;
\nstruct rtgenmsg *rtgenm;
\nstruct igmpmsg *msg;
\nstruct sk_buff *skb;
\nstruct nlattr *nla;
\nint payloadlen;<\/p>\npayloadlen = pkt->len – sizeof(struct igmpmsg);
\nmsg = (struct igmpmsg *)skb_network_header(pkt);<\/p>\nskb = nlmsg_new(igmpmsg_netlink_msgsize(payloadlen), GFP_ATOMIC);
\nif (!skb)
\ngoto errout;<\/p>\nnlh = nlmsg_put(skb, 0, 0, RTM_NEWCACHEREPORT,
\nsizeof(struct rtgenmsg), 0);
\nif (!nlh)
\ngoto errout;
\nrtgenm = nlmsg_data(nlh);
\nrtgenm->rtgen_family = RTNL_FAMILY_IPMR;
\nif (nla_put_u8(skb, IPMRA_CREPORT_MSGTYPE, msg->im_msgtype) ||
\n nla_put_u32(skb, IPMRA_CREPORT_VIF_ID, msg->im_vif) ||
\n nla_put_in_addr(skb, IPMRA_CREPORT_SRC_ADDR,
\n msg->im_src.s_addr) ||
\n nla_put_in_addr(skb, IPMRA_CREPORT_DST_ADDR,
\n msg->im_dst.s_addr))
\ngoto nla_put_failure;<\/p>\nnla = nla_reserve(skb, IPMRA_CREPORT_PKT, payloadlen);
\nif (!nla || skb_copy_bits(pkt, sizeof(struct igmpmsg),
\n nla_data(nla), payloadlen))
\ngoto nla_put_failure;<\/p>\nnlmsg_end(skb, nlh);<\/p>\n
rtnl_notify(skb, net, 0, RTNLGRP_IPV4_MROUTE_R, NULL, GFP_ATOMIC);
\nreturn;<\/p>\nnla_put_failure:
\nnlmsg_cancel(skb, nlh);
\nerrout:
\nkfree_skb(skb);
\nrtnl_set_sk_err(net, RTNLGRP_IPV4_MROUTE_R, -ENOBUFS);
\n}<\/p>\nstatic int ipmr_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh,
\n struct netlink_ext_ack *extack)
\n{
\nstruct net *net = sock_net(in_skb->sk);
\nstruct nlattr *tb[RTA_MAX + 1];
\nstruct sk_buff *skb = NULL;
\nstruct mfc_cache *cache;
\nstruct mr_table *mrt;
\nstruct rtmsg *rtm;
\n__be32 src, grp;
\nu32 tableid;
\nint err;<\/p>\nerr = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX,
\n rtm_ipv4_policy, extack);
\nif (err < 0)
\ngoto errout;<\/p>\nrtm = nlmsg_data(nlh);<\/p>\n
src = tb[RTA_SRC] ? nla_get_in_addr(tb[RTA_SRC]) : 0;
\ngrp = tb[RTA_DST] ? nla_get_in_addr(tb[RTA_DST]) : 0;
\ntableid = tb[RTA_TABLE] ? nla_get_u32(tb[RTA_TABLE]) : 0;<\/p>\nmrt = ipmr_get_table(net, tableid ? tableid : RT_TABLE_DEFAULT);
\nif (!mrt) {
\nerr = -ENOENT;
\ngoto errout_free;
\n}<\/p>\n\/* entries are added\/deleted only under RTNL *\/
\nrcu_read_lock();
\ncache = ipmr_cache_find(mrt, src, grp);
\nrcu_read_unlock();
\nif (!cache) {
\nerr = -ENOENT;
\ngoto errout_free;
\n}<\/p>\nskb = nlmsg_new(mroute_msgsize(false, mrt->maxvif), GFP_KERNEL);
\nif (!skb) {
\nerr = -ENOBUFS;
\ngoto errout_free;
\n}<\/p>\nerr = ipmr_fill_mroute(mrt, skb, NETLINK_CB(in_skb).portid,
\n nlh->nlmsg_seq, cache,
\n RTM_NEWROUTE, 0);
\nif (err < 0)
\ngoto errout_free;<\/p>\nerr = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);<\/p>\n
errout:
\nreturn err;<\/p>\nerrout_free:
\nkfree_skb(skb);
\ngoto errout;
\n}<\/p>\nstatic int ipmr_rtm_dumproute(struct sk_buff *skb, struct netlink_callback *cb)
\n{
\nreturn mr_rtm_dumproute(skb, cb, ipmr_mr_table_iter,
\n_ipmr_fill_mroute, &mfc_unres_lock);
\n}<\/p>\nstatic const struct nla_policy rtm_ipmr_policy[RTA_MAX + 1] = {
\n[RTA_SRC]= { .type = NLA_U32 },
\n[RTA_DST]= { .type = NLA_U32 },
\n[RTA_IIF]= { .type = NLA_U32 },
\n[RTA_TABLE]= { .type = NLA_U32 },
\n[RTA_MULTIPATH]= { .len = sizeof(struct rtnexthop) },
\n};<\/p>\nstatic bool ipmr_rtm_validate_proto(unsigned char rtm_protocol)
\n{
\nswitch (rtm_protocol) {
\ncase RTPROT_STATIC:
\ncase RTPROT_MROUTED:
\nreturn true;
\n}
\nreturn false;
\n}<\/p>\nstatic int ipmr_nla_get_ttls(const struct nlattr *nla, struct mfcctl *mfcc)
\n{
\nstruct rtnexthop *rtnh = nla_data(nla);
\nint remaining = nla_len(nla), vifi = 0;<\/p>\nwhile (rtnh_ok(rtnh, remaining)) {
\nmfcc->mfcc_ttls[vifi] = rtnh->rtnh_hops;
\nif (++vifi == MAXVIFS)
\nbreak;
\nrtnh = rtnh_next(rtnh, &remaining);
\n}<\/p>\nreturn remaining > 0 ? -EINVAL : vifi;
\n}<\/p>\n\/* returns < 0 on error, 0 for ADD_MFC and 1 for ADD_MFC_PROXY *\/
\nstatic int rtm_to_ipmr_mfcc(struct net *net, struct nlmsghdr *nlh,
\n struct mfcctl *mfcc, int *mrtsock,
\n struct mr_table **mrtret,
\n struct netlink_ext_ack *extack)
\n{
\nstruct net_device *dev = NULL;
\nu32 tblid = RT_TABLE_DEFAULT;
\nstruct mr_table *mrt;
\nstruct nlattr *attr;
\nstruct rtmsg *rtm;
\nint ret, rem;<\/p>\nret = nlmsg_validate(nlh, sizeof(*rtm), RTA_MAX, rtm_ipmr_policy,
\n extack);
\nif (ret < 0)
\ngoto out;
\nrtm = nlmsg_data(nlh);<\/p>\nret = -EINVAL;
\nif (rtm->rtm_family != RTNL_FAMILY_IPMR || rtm->rtm_dst_len != 32 ||
\n rtm->rtm_type != RTN_MULTICAST ||
\n rtm->rtm_scope != RT_SCOPE_UNIVERSE ||
\n !ipmr_rtm_validate_proto(rtm->rtm_protocol))
\ngoto out;<\/p>\nmemset(mfcc, 0, sizeof(*mfcc));
\nmfcc->mfcc_parent = -1;
\nret = 0;
\nnlmsg_for_each_attr(attr, nlh, sizeof(struct rtmsg), rem) {
\nswitch (nla_type(attr)) {
\ncase RTA_SRC:
\nmfcc->mfcc_origin.s_addr = nla_get_be32(attr);
\nbreak;
\ncase RTA_DST:
\nmfcc->mfcc_mcastgrp.s_addr = nla_get_be32(attr);
\nbreak;
\ncase RTA_IIF:
\ndev = __dev_get_by_index(net, nla_get_u32(attr));
\nif (!dev) {
\nret = -ENODEV;
\ngoto out;
\n}
\nbreak;
\ncase RTA_MULTIPATH:
\nif (ipmr_nla_get_ttls(attr, mfcc) < 0) {
\nret = -EINVAL;
\ngoto out;
\n}
\nbreak;
\ncase RTA_PREFSRC:
\nret = 1;
\nbreak;
\ncase RTA_TABLE:
\ntblid = nla_get_u32(attr);
\nbreak;
\n}
\n}
\nmrt = ipmr_get_table(net, tblid);
\nif (!mrt) {
\nret = -ENOENT;
\ngoto out;
\n}
\n*mrtret = mrt;
\n*mrtsock = rtm->rtm_protocol == RTPROT_MROUTED ? 1 : 0;
\nif (dev)
\nmfcc->mfcc_parent = ipmr_find_vif(mrt, dev);<\/p>\nout:
\nreturn ret;
\n}<\/p>\n\/* takes care of both newroute and delroute *\/
\nstatic int ipmr_rtm_route(struct sk_buff *skb, struct nlmsghdr *nlh,
\n struct netlink_ext_ack *extack)
\n{
\nstruct net *net = sock_net(skb->sk);
\nint ret, mrtsock, parent;
\nstruct mr_table *tbl;
\nstruct mfcctl mfcc;<\/p>\nmrtsock = 0;
\ntbl = NULL;
\nret = rtm_to_ipmr_mfcc(net, nlh, &mfcc, &mrtsock, &tbl, extack);
\nif (ret < 0)
\nreturn ret;<\/p>\nparent = ret ? mfcc.mfcc_parent : -1;
\nif (nlh->nlmsg_type == RTM_NEWROUTE)
\nreturn ipmr_mfc_add(net, tbl, &mfcc, mrtsock, parent);
\nelse
\nreturn ipmr_mfc_delete(tbl, &mfcc, parent);
\n}<\/p>\nstatic bool ipmr_fill_table(struct mr_table *mrt, struct sk_buff *skb)
\n{
\nu32 queue_len = atomic_read(&mrt->cache_resolve_queue_len);<\/p>\nif (nla_put_u32(skb, IPMRA_TABLE_ID, mrt->id) ||
\n nla_put_u32(skb, IPMRA_TABLE_CACHE_RES_QUEUE_LEN, queue_len) ||
\n nla_put_s32(skb, IPMRA_TABLE_MROUTE_REG_VIF_NUM,
\nmrt->mroute_reg_vif_num) ||
\n nla_put_u8(skb, IPMRA_TABLE_MROUTE_DO_ASSERT,
\n mrt->mroute_do_assert) ||
\n nla_put_u8(skb, IPMRA_TABLE_MROUTE_DO_PIM, mrt->mroute_do_pim) ||
\n nla_put_u8(skb, IPMRA_TABLE_MROUTE_DO_WRVIFWHOLE,
\n mrt->mroute_do_wrvifwhole))
\nreturn false;<\/p>\nreturn true;
\n}<\/p>\nstatic bool ipmr_fill_vif(struct mr_table *mrt, u32 vifid, struct sk_buff *skb)
\n{
\nstruct nlattr *vif_nest;
\nstruct vif_device *vif;<\/p>\n\/* if the VIF doesn't exist just continue *\/
\nif (!VIF_EXISTS(mrt, vifid))
\nreturn true;<\/p>\nvif = &mrt->vif_table[vifid];
\nvif_nest = nla_nest_start(skb, IPMRA_VIF);
\nif (!vif_nest)
\nreturn false;
\nif (nla_put_u32(skb, IPMRA_VIFA_IFINDEX, vif->dev->ifindex) ||
\n nla_put_u32(skb, IPMRA_VIFA_VIF_ID, vifid) ||
\n nla_put_u16(skb, IPMRA_VIFA_FLAGS, vif->flags) ||
\n nla_put_u64_64bit(skb, IPMRA_VIFA_BYTES_IN, vif->bytes_in,
\n IPMRA_VIFA_PAD) ||
\n nla_put_u64_64bit(skb, IPMRA_VIFA_BYTES_OUT, vif->bytes_out,
\n IPMRA_VIFA_PAD) ||
\n nla_put_u64_64bit(skb, IPMRA_VIFA_PACKETS_IN, vif->pkt_in,
\n IPMRA_VIFA_PAD) ||
\n nla_put_u64_64bit(skb, IPMRA_VIFA_PACKETS_OUT, vif->pkt_out,
\n IPMRA_VIFA_PAD) ||
\n nla_put_be32(skb, IPMRA_VIFA_LOCAL_ADDR, vif->local) ||
\n nla_put_be32(skb, IPMRA_VIFA_REMOTE_ADDR, vif->remote)) {
\nnla_nest_cancel(skb, vif_nest);
\nreturn false;
\n}
\nnla_nest_end(skb, vif_nest);<\/p>\nreturn true;
\n}<\/p>\nstatic int ipmr_rtm_dumplink(struct sk_buff *skb, struct netlink_callback *cb)
\n{
\nstruct net *net = sock_net(skb->sk);
\nstruct nlmsghdr *nlh = NULL;
\nunsigned int t = 0, s_t;
\nunsigned int e = 0, s_e;
\nstruct mr_table *mrt;<\/p>\ns_t = cb->args[0];
\ns_e = cb->args[1];<\/p>\nipmr_for_each_table(mrt, net) {
\nstruct nlattr *vifs, *af;
\nstruct ifinfomsg *hdr;
\nu32 i;<\/p>\nif (t < s_t)
\ngoto skip_table;
\nnlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid,
\ncb->nlh->nlmsg_seq, RTM_NEWLINK,
\nsizeof(*hdr), NLM_F_MULTI);
\nif (!nlh)
\nbreak;<\/p>\nhdr = nlmsg_data(nlh);
\nmemset(hdr, 0, sizeof(*hdr));
\nhdr->ifi_family = RTNL_FAMILY_IPMR;<\/p>\naf = nla_nest_start(skb, IFLA_AF_SPEC);
\nif (!af) {
\nnlmsg_cancel(skb, nlh);
\ngoto out;
\n}<\/p>\nif (!ipmr_fill_table(mrt, skb)) {
\nnlmsg_cancel(skb, nlh);
\ngoto out;
\n}<\/p>\nvifs = nla_nest_start(skb, IPMRA_TABLE_VIFS);
\nif (!vifs) {
\nnla_nest_end(skb, af);
\nnlmsg_end(skb, nlh);
\ngoto out;
\n}
\nfor (i = 0; i < mrt->maxvif; i++) {
\nif (e < s_e)
\ngoto skip_entry;
\nif (!ipmr_fill_vif(mrt, i, skb)) {
\nnla_nest_end(skb, vifs);
\nnla_nest_end(skb, af);
\nnlmsg_end(skb, nlh);
\ngoto out;
\n}
\nskip_entry:
\ne++;
\n}
\ns_e = 0;
\ne = 0;
\nnla_nest_end(skb, vifs);
\nnla_nest_end(skb, af);
\nnlmsg_end(skb, nlh);
\nskip_table:
\nt++;
\n}<\/p>\nout:
\ncb->args[1] = e;
\ncb->args[0] = t;<\/p>\nreturn skb->len;
\n}<\/p>\n#ifdef CONFIG_PROC_FS
\n\/* The \/proc interfaces to multicast routing :
\n * \/proc\/net\/ip_mr_cache & \/proc\/net\/ip_mr_vif
\n *\/<\/p>\nstatic void *ipmr_vif_seq_start(struct seq_file *seq, loff_t *pos)
\n__acquires(mrt_lock)
\n{
\nstruct mr_vif_iter *iter = seq->private;
\nstruct net *net = seq_file_net(seq);
\nstruct mr_table *mrt;<\/p>\nmrt = ipmr_get_table(net, RT_TABLE_DEFAULT);
\nif (!mrt)
\nreturn ERR_PTR(-ENOENT);<\/p>\niter->mrt = mrt;<\/p>\n
read_lock(&mrt_lock);
\nreturn mr_vif_seq_start(seq, pos);
\n}<\/p>\nstatic void ipmr_vif_seq_stop(struct seq_file *seq, void *v)
\n__releases(mrt_lock)
\n{
\nread_unlock(&mrt_lock);
\n}<\/p>\nstatic int ipmr_vif_seq_show(struct seq_file *seq, void *v)
\n{
\nstruct mr_vif_iter *iter = seq->private;
\nstruct mr_table *mrt = iter->mrt;<\/p>\nif (v == SEQ_START_TOKEN) {
\nseq_puts(seq,
\n "Interface BytesIn PktsIn BytesOut PktsOut Flags Local Remote\\\\n");
\n} else {
\nconst struct vif_device *vif = v;
\nconst char *name = vif->dev ?
\n vif->dev->name : "none";<\/p>\nseq_printf(seq,
\n "%2td %-10s %8ld %7ld %8ld %7ld %05X %08X %08X\\\\n",
\n vif – mrt->vif_table,
\n name, vif->bytes_in, vif->pkt_in,
\n vif->bytes_out, vif->pkt_out,
\n vif->flags, vif->local, vif->remote);
\n}
\nreturn 0;
\n}<\/p>\nstatic const struct seq_operations ipmr_vif_seq_ops = {
\n.start = ipmr_vif_seq_start,
\n.next = mr_vif_seq_next,
\n.stop = ipmr_vif_seq_stop,
\n.show = ipmr_vif_seq_show,
\n};<\/p>\nstatic void *ipmr_mfc_seq_start(struct seq_file *seq, loff_t *pos)
\n{
\nstruct net *net = seq_file_net(seq);
\nstruct mr_table *mrt;<\/p>\nmrt = ipmr_get_table(net, RT_TABLE_DEFAULT);
\nif (!mrt)
\nreturn ERR_PTR(-ENOENT);<\/p>\nreturn mr_mfc_seq_start(seq, pos, mrt, &mfc_unres_lock);
\n}<\/p>\nstatic int ipmr_mfc_seq_show(struct seq_file *seq, void *v)
\n{
\nint n;<\/p>\nif (v == SEQ_START_TOKEN) {
\nseq_puts(seq,
\n "Group Origin Iif Pkts Bytes Wrong Oifs\\\\n");
\n} else {
\nconst struct mfc_cache *mfc = v;
\nconst struct mr_mfc_iter *it = seq->private;
\nconst struct mr_table *mrt = it->mrt;<\/p>\nseq_printf(seq, "%08X %08X %-3hd",
\n (__force u32) mfc->mfc_mcastgrp,
\n (__force u32) mfc->mfc_origin,
\n mfc->_c.mfc_parent);<\/p>\nif (it->cache != &mrt->mfc_unres_queue) {
\nseq_printf(seq, " %8lu %8lu %8lu",
\n mfc->_c.mfc_un.res.pkt,
\n mfc->_c.mfc_un.res.bytes,
\n mfc->_c.mfc_un.res.wrong_if);
\nfor (n = mfc->_c.mfc_un.res.minvif;
\n n < mfc->_c.mfc_un.res.maxvif; n++) {
\nif (VIF_EXISTS(mrt, n) &&
\n mfc->_c.mfc_un.res.ttls[n] < 255)
\nseq_printf(seq,
\n " %2d:%-3d",
\n n, mfc->_c.mfc_un.res.ttls[n]);
\n}
\n} else {
\n\/* unresolved mfc_caches don't contain
\n * pkt, bytes and wrong_if values
\n *\/
\nseq_printf(seq, " %8lu %8lu %8lu", 0ul, 0ul, 0ul);
\n}
\nseq_putc(seq, '\\\\n');
\n}
\nreturn 0;
\n}<\/p>\nstatic const struct seq_operations ipmr_mfc_seq_ops = {
\n.start = ipmr_mfc_seq_start,
\n.next = mr_mfc_seq_next,
\n.stop = mr_mfc_seq_stop,
\n.show = ipmr_mfc_seq_show,
\n};
\n#endif<\/p>\n#ifdef CONFIG_IP_PIMSM_V2
\nstatic const struct net_protocol pim_protocol = {
\n.handler=pim_rcv,
\n.netns_ok=1,
\n};
\n#endif<\/p>\nstatic unsigned int ipmr_seq_read(struct net *net)
\n{
\nASSERT_RTNL();<\/p>\nreturn net->ipv4.ipmr_seq + ipmr_rules_seq_read(net);
\n}<\/p>\nstatic int ipmr_dump(struct net *net, struct notifier_block *nb)
\n{
\nreturn mr_dump(net, nb, RTNL_FAMILY_IPMR, ipmr_rules_dump,
\n ipmr_mr_table_iter, &mrt_lock);
\n}<\/p>\nstatic const struct fib_notifier_ops ipmr_notifier_ops_template = {
\n.family= RTNL_FAMILY_IPMR,
\n.fib_seq_read= ipmr_seq_read,
\n.fib_dump= ipmr_dump,
\n.owner= THIS_MODULE,
\n};<\/p>\nstatic int __net_init ipmr_notifier_init(struct net *net)
\n{
\nstruct fib_notifier_ops *ops;<\/p>\nnet->ipv4.ipmr_seq = 0;<\/p>\n
ops = fib_notifier_ops_register(&ipmr_notifier_ops_template, net);
\nif (IS_ERR(ops))
\nreturn PTR_ERR(ops);
\nnet->ipv4.ipmr_notifier_ops = ops;<\/p>\nreturn 0;
\n}<\/p>\nstatic void __net_exit ipmr_notifier_exit(struct net *net)
\n{
\nfib_notifier_ops_unregister(net->ipv4.ipmr_notifier_ops);
\nnet->ipv4.ipmr_notifier_ops = NULL;
\n}<\/p>\n\/* Setup for IP multicast routing *\/
\nstatic int __net_init ipmr_net_init(struct net *net)
\n{
\nint err;<\/p>\nerr = ipmr_notifier_init(net);
\nif (err)
\ngoto ipmr_notifier_fail;<\/p>\nerr = ipmr_rules_init(net);
\nif (err < 0)
\ngoto ipmr_rules_fail;<\/p>\n#ifdef CONFIG_PROC_FS
\nerr = -ENOMEM;
\nif (!proc_create_net("ip_mr_vif", 0, net->proc_net, &ipmr_vif_seq_ops,
\nsizeof(struct mr_vif_iter)))
\ngoto proc_vif_fail;
\nif (!proc_create_net("ip_mr_cache", 0, net->proc_net, &ipmr_mfc_seq_ops,
\nsizeof(struct mr_mfc_iter)))
\ngoto proc_cache_fail;
\n#endif
\nreturn 0;<\/p>\n#ifdef CONFIG_PROC_FS
\nproc_cache_fail:
\nremove_proc_entry("ip_mr_vif", net->proc_net);
\nproc_vif_fail:
\nipmr_rules_exit(net);
\n#endif
\nipmr_rules_fail:
\nipmr_notifier_exit(net);
\nipmr_notifier_fail:
\nreturn err;
\n}<\/p>\nstatic void __net_exit ipmr_net_exit(struct net *net)
\n{
\n#ifdef CONFIG_PROC_FS
\nremove_proc_entry("ip_mr_cache", net->proc_net);
\nremove_proc_entry("ip_mr_vif", net->proc_net);
\n#endif
\nipmr_notifier_exit(net);
\nipmr_rules_exit(net);
\n}<\/p>\nstatic struct pernet_operations ipmr_net_ops = {
\n.init = ipmr_net_init,
\n.exit = ipmr_net_exit,
\n};<\/p>\nint __init ip_mr_init(void)
\n{
\nint err;<\/p>\nmrt_cachep = kmem_cache_create("ip_mrt_cache",
\n sizeof(struct mfc_cache),
\n 0, SLAB_HWCACHE_ALIGN | SLAB_PANIC,
\n NULL);<\/p>\nerr = register_pernet_subsys(&ipmr_net_ops);
\nif (err)
\ngoto reg_pernet_fail;<\/p>\nerr = register_netdevice_notifier(&ip_mr_notifier);
\nif (err)
\ngoto reg_notif_fail;
\n#ifdef CONFIG_IP_PIMSM_V2
\nif (inet_add_protocol(&pim_protocol, IPPROTO_PIM) < 0) {
\npr_err("%s: can't add PIM protocol\\\\n", __func__);
\nerr = -EAGAIN;
\ngoto add_proto_fail;
\n}
\n#endif
\nrtnl_register(RTNL_FAMILY_IPMR, RTM_GETROUTE,
\n ipmr_rtm_getroute, ipmr_rtm_dumproute, 0);
\nrtnl_register(RTNL_FAMILY_IPMR, RTM_NEWROUTE,
\n ipmr_rtm_route, NULL, 0);
\nrtnl_register(RTNL_FAMILY_IPMR, RTM_DELROUTE,
\n ipmr_rtm_route, NULL, 0);<\/p>\nrtnl_register(RTNL_FAMILY_IPMR, RTM_GETLINK,
\n NULL, ipmr_rtm_dumplink, 0);
\nreturn 0;<\/p>\n#ifdef CONFIG_IP_PIMSM_V2
\nadd_proto_fail:
\nunregister_netdevice_notifier(&ip_mr_notifier);
\n#endif
\nreg_notif_fail:
\nunregister_pernet_subsys(&ipmr_net_ops);
\nreg_pernet_fail:
\nkmem_cache_destroy(mrt_cachep);
\nreturn err;
\n}<\/p>\nnet\/ipv4\/ipmr.c\u00a0\u662f Linux \u5185\u6838\u4e2d\u5b9e\u73b0 IPv4 \u591a\u64ad\u8def\u7531\u7684\u6838\u5fc3\u6587\u4ef6，\u4e3b\u8981\u652f\u6301\u00a0mrouted\u00a0\u548c PIM（Protocol Independent Multicast）\u534f\u8bae\u3002\u4ee5\u4e0b\u662f\u5bf9\u5176\u5173\u952e\u90e8\u5206\u7684\u8be6\u7ec6\u5206\u6790：<\/p>\n
\n1. \u6838\u5fc3\u6570\u636e\u7ed3\u6784<\/h4>\n
a) \u591a\u64ad\u8def\u7531\u8868 (struct mr_table)<\/h5>\n
\u7ba1\u7406\u591a\u64ad\u8def\u7531\u4fe1\u606f，\u5305\u542b：<\/p>\n
- \n
- \n
\u865a\u62df\u63a5\u53e3\u8868 (vif_table): \u5b58\u50a8\u6240\u6709\u865a\u62df\u63a5\u53e3（VIF）\u4fe1\u606f\u3002<\/p>\n<\/li>\n
- \n
\u591a\u64ad\u8f6c\u53d1\u7f13\u5b58 (MFC): \u4f7f\u7528\u54c8\u5e0c\u8868 (mfc_hash) \u5b58\u50a8\u5df2\u89e3\u6790\u7684\u8def\u7531\u6761\u76ee\u3002<\/p>\n<\/li>\n
- \n
\u672a\u89e3\u6790\u961f\u5217 (mfc_unres_queue): \u4e34\u65f6\u5b58\u653e\u5f85\u5904\u7406\u7684\u591a\u64ad\u5305\u3002<\/p>\n<\/li>\n
- \n
\u5b9a\u65f6\u5668 (ipmr_expire_timer): \u6e05\u7406\u8d85\u65f6\u672a\u89e3\u6790\u7684\u6761\u76ee\u3002<\/p>\n<\/li>\n<\/ul>\n
b) \u865a\u62df\u63a5\u53e3 (struct vif_device)<\/h5>\n
\u8868\u793a\u4e00\u4e2a\u591a\u64ad\u865a\u62df\u63a5\u53e3：<\/p>\n
- \n
- \n
\u8bbe\u5907\u6307\u9488 (dev): \u5173\u8054\u7684\u7f51\u7edc\u8bbe\u5907\u3002<\/p>\n<\/li>\n
- \n
\u672c\u5730\/\u8fdc\u7a0b\u5730\u5740 (local,\u00a0remote): \u96a7\u9053\u7aef\u70b9\u5730\u5740\u3002<\/p>\n<\/li>\n
- \n
\u7edf\u8ba1\u4fe1\u606f: \u6536\u53d1\u5305\u6570\u3001\u5b57\u8282\u6570\u7b49\u3002<\/p>\n<\/li>\n
- \n
\u6807\u5fd7\u4f4d (flags):
\nVIFF_TUNNEL（\u96a7\u9053\u63a5\u53e3）\u3001VIFF_REGISTER（\u6ce8\u518c\u5230\u7528\u6237\u6001）\u3001VIFF_STATIC（\u9759\u6001\u914d\u7f6e）\u3002<\/p>\n<\/li>\n<\/ul>\nc) \u591a\u64ad\u8f6c\u53d1\u7f13\u5b58 (struct mfc_cache)<\/h5>\n
\u5b58\u50a8\u591a\u64ad\u8def\u7531\u6761\u76ee：<\/p>\n
- \n
- \n
\u6e90\u5730\u5740\/\u7ec4\u5730\u5740 (mfc_origin,\u00a0mfc_mcastgrp): \u6807\u8bc6\u6d41\u3002<\/p>\n<\/li>\n
- \n
\u8f93\u5165\u63a5\u53e3 (mfc_parent): \u63a5\u6536\u6d41\u91cf\u7684 VIF\u3002<\/p>\n<\/li>\n
- \n
\u8f93\u51fa\u63a5\u53e3 TTL \u6620\u5c04 (res.ttls): \u6bcf\u4e2a VIF \u7684 TTL \u9608\u503c\u3002<\/p>\n<\/li>\n
- \n
\u7edf\u8ba1\u4fe1\u606f: \u8f6c\u53d1\u5305\u6570\u3001\u5b57\u8282\u6570\u3001\u9519\u8bef\u8ba1\u6570\u3002<\/p>\n<\/li>\n<\/ul>\n
\n2. \u6838\u5fc3\u529f\u80fd\u5b9e\u73b0<\/h4>\n
a) \u865a\u62df\u63a5\u53e3\u7ba1\u7406<\/h5>\n
- \n
- \n
\u521b\u5efa (vif_add)
\n\u652f\u6301\u4e09\u79cd\u7c7b\u578b\u63a5\u53e3：<\/p>\n- \n
- \n
VIFF_REGISTER: \u6ce8\u518c\u5230\u7528\u6237\u6001\u5b88\u62a4\u8fdb\u7a0b（\u5982\u00a0pimd）\u3002<\/p>\n<\/li>\n
- \n
VIFF_TUNNEL: \u521b\u5efa IP-in-IP \u96a7\u9053（\u5982 DVMRP）\u3002<\/p>\n<\/li>\n
- \n
\u7269\u7406\u63a5\u53e3: \u7ed1\u5b9a\u5230\u5b9e\u9645\u7f51\u7edc\u8bbe\u5907\u3002<\/p>\n<\/li>\n<\/ul>\n<\/li>\n
- \n
\u5220\u9664 (vif_delete)
\n\u89e3\u9664\u8bbe\u5907\u7ed1\u5b9a，\u66f4\u65b0\u7edf\u8ba1，\u6e05\u7406\u5173\u8054\u8d44\u6e90\u3002<\/p>\n<\/li>\n<\/ul>\nb) MFC \u6761\u76ee\u7ba1\u7406<\/h5>\n
- \n
- \n
\u52a8\u6001\u5b66\u4e60 (ipmr_cache_find)
\n\u901a\u8fc7\u54c8\u5e0c\u8868\u5feb\u901f\u67e5\u627e MFC \u6761\u76ee\u3002<\/p>\n<\/li>\n - \n
\u9759\u6001\u914d\u7f6e (ipmr_mfc_add)
\n\u901a\u8fc7 Netlink \u6216 Socket \u6dfb\u52a0\u9759\u6001\u8def\u7531\u3002<\/p>\n<\/li>\n - \n
\u8d85\u65f6\u5904\u7406 (ipmr_expire_process)
\n\u6e05\u7406\u672a\u89e3\u6790\u7684 MFC \u6761\u76ee（\u9ed8\u8ba4 10 \u79d2\u8d85\u65f6）\u3002<\/p>\n<\/li>\n<\/ul>\nc) \u6570\u636e\u5305\u8f6c\u53d1 (ip_mr_forward)<\/h5>\n
\u5904\u7406\u6d41\u7a0b：<\/p>\n
- \n
\u67e5\u627e MFC: \u5339\u914d\u6e90\u5730\u5740\u548c\u7ec4\u5730\u5740\u3002<\/p>\n<\/li>\n
- \n
\u9a8c\u8bc1\u8f93\u5165\u63a5\u53e3: \u68c0\u67e5\u5305\u662f\u5426\u4ece\u6b63\u786e VIF \u8fdb\u5165\u3002<\/p>\n<\/li>\n
- \n
TTL \u68c0\u67e5: \u8df3\u8fc7 TTL \u4e0d\u8db3\u7684\u51fa\u53e3\u3002<\/p>\n<\/li>\n
- \n
\u514b\u9686\u5305\u591a\u64ad\u8f6c\u53d1:<\/p>\n
- \n
- \n
\u96a7\u9053\u63a5\u53e3：\u5c01\u88c5 IP-in-IP \u5934\u3002<\/p>\n<\/li>\n
- \n
\u7269\u7406\u63a5\u53e3：\u76f4\u63a5\u53d1\u9001\u3002<\/p>\n<\/li>\n
- \n
\u6ce8\u518c\u63a5\u53e3：\u63d0\u4ea4\u7ed9\u7528\u6237\u6001\u5b88\u62a4\u8fdb\u7a0b\u3002<\/p>\n<\/li>\n<\/ul>\n<\/li>\n
d) \u672a\u89e3\u6790\u5305\u5904\u7406 (ipmr_cache_unresolved)<\/h5>\n
\u5f53 MFC \u4e0d\u5b58\u5728\u65f6：<\/p>\n
- \n
\u521b\u5efa\u4e34\u65f6 MFC \u6761\u76ee\u5e76\u52a0\u5165\u672a\u89e3\u6790\u961f\u5217\u3002<\/p>\n<\/li>\n
- \n
\u53d1\u9001\u00a0IGMPMSG_NOCACHE\u00a0\u901a\u77e5\u7528\u6237\u6001\u3002<\/p>\n<\/li>\n
- \n
\u6536\u5230\u54cd\u5e94\u540e\u89e3\u6790\u6761\u76ee\u5e76\u8f6c\u53d1\u7f13\u5b58\u7684\u5305\u3002<\/p>\n<\/li>\n
\n3. \u5173\u952e\u534f\u8bae\u652f\u6301<\/h4>\n
a) PIM \u534f\u8bae\u5904\u7406<\/h5>\n
- \n
- \n
PIMv1 (pim_rcv_v1)
\n\u5904\u7406 PIM \u6ce8\u518c\u6d88\u606f，\u5c01\u88c5\u5305\u8f6c\u53d1\u5230 RP\u3002<\/p>\n<\/li>\n - \n
PIMv2 (pim_rcv)
\n\u6821\u9a8c\u6d88\u606f\u6709\u6548\u6027，\u8f6c\u53d1\u5230\u6ce8\u518c\u63a5\u53e3\u3002<\/p>\n<\/li>\n<\/ul>\nb) IGMP \u6d88\u606f<\/h5>\n
- \n
- \n
\u7f13\u5b58\u62a5\u544a (ipmr_cache_report)
\n\u53d1\u9001\u00a0IGMPMSG_WHOLEPKT\u00a0\u901a\u77e5\u7528\u6237\u6001\u65b0\u6d41\u91cf\u3002<\/p>\n<\/li>\n<\/ul>\n
\n4. \u63a7\u5236\u5e73\u9762\u63a5\u53e3<\/h4>\n
a) Netlink \u64cd\u4f5c<\/h5>\n
- \n
- \n
\u8def\u7531\u64cd\u4f5c (ipmr_rtm_route)
\n\u5904\u7406\u00a0RTM_NEWROUTE\/RTM_DELROUTE\u00a0\u6dfb\u52a0\/\u5220\u9664 MFC\u3002<\/p>\n<\/li>\n - \n
\u4fe1\u606f\u67e5\u8be2 (ipmr_rtm_dumplink)
\n\u901a\u8fc7\u00a0RTM_GETLINK\u00a0\u8fd4\u56de VIF \u548c MFC \u8868\u4fe1\u606f\u3002<\/p>\n<\/li>\n<\/ul>\nb) Sysctl \/ Procfs<\/h5>\n
- \n
- \n
\/proc\/net\/ip_mr_vif
\n\u663e\u793a\u6240\u6709 VIF \u7684\u7edf\u8ba1\u4fe1\u606f\u3002<\/p>\n<\/li>\n - \n
\/proc\/net\/ip_mr_cache
\n\u5217\u51fa MFC \u6761\u76ee，\u5305\u62ec\u6e90\u7ec4\u5730\u5740\u3001\u8f6c\u53d1\u8ba1\u6570\u3002<\/p>\n<\/li>\n<\/ul>\nc) Socket IOCTL<\/h5>\n
- \n
- \n
SIOCGETVIFCNT
\n\u83b7\u53d6\u6307\u5b9a VIF \u7684\u6d41\u91cf\u7edf\u8ba1\u3002<\/p>\n<\/li>\n - \n
SIOCGETSGCNT
\n\u67e5\u8be2\u7279\u5b9a\u591a\u64ad\u6d41\u7684\u8f6c\u53d1\u7edf\u8ba1\u3002<\/p>\n<\/li>\n<\/ul>\n
\n5. \u521d\u59cb\u5316\u548c\u6e05\u7406<\/h4>\n
- \n
- \n
\u521d\u59cb\u5316 (ip_mr_init)<\/p>\n
- \n
\u6ce8\u518c\u7f51\u7edc\u5b50\u7cfb\u7edf (register_pernet_subsys)\u3002<\/p>\n<\/li>\n
- \n
\u521b\u5efa MFC \u7f13\u5b58\u5185\u5b58\u6c60 (kmem_cache_create)\u3002<\/p>\n<\/li>\n
- \n
\u6ce8\u518c Netlink \u64cd\u4f5c\u548c PIM \u534f\u8bae\u5904\u7406\u5668\u3002<\/p>\n<\/li>\n
- \n
\u6302\u8f7d Procfs \u6587\u4ef6\u3002<\/p>\n<\/li>\n<\/li>\n
- \n
\u9000\u51fa\u6e05\u7406
\n\u91ca\u653e\u6240\u6709\u8def\u7531\u8868\u3001\u5b9a\u65f6\u5668\u3001Procfs \u9879\u3002<\/p>\n<\/li>\n<\/ul>\n
\n6. \u8bbe\u8ba1\u4eae\u70b9<\/h4>\n
- \n
- \n
\u591a\u8868\u652f\u6301 (CONFIG_IP_MROUTE_MULTIPLE_TABLES)
\n\u5141\u8bb8\u521b\u5efa\u591a\u4e2a\u72ec\u7acb\u7684\u591a\u64ad\u8def\u7531\u8868\u3002<\/p>\n<\/li>\n - \n
\u9ad8\u6548\u67e5\u627e
\n\u4f7f\u7528 RCU \u4fdd\u62a4\u7684\u54c8\u5e0c\u8868\u7ba1\u7406 MFC\u3002<\/p>\n<\/li>\n - \n
\u7528\u6237\u6001\u534f\u4f5c
\n\u901a\u8fc7\u539f\u59cb\u5957\u63a5\u5b57 (mroute_sk) \u4e0e\u00a0mrouted\/pimd\u00a0\u4ea4\u4e92\u3002<\/p>\n<\/li>\n - \n
\u6a21\u5757\u5316\u7ed3\u6784
\n\u5206\u79bb\u8f6c\u53d1\/\u63a7\u5236\u903b\u8f91，\u652f\u6301\u52a8\u6001\u6269\u5c55\u3002<\/p>\n<\/li>\n<\/ul>\n
\n\u603b\u7ed3<\/h4>\n
ipmr.c\u00a0\u5b9e\u73b0\u4e86\u5b8c\u6574\u7684 IPv4 \u591a\u64ad\u8def\u7531\u6846\u67b6，\u6838\u5fc3\u529f\u80fd\u5305\u62ec：<\/p>\n
- \n
\u865a\u62df\u63a5\u53e3\u7ba1\u7406：\u652f\u6301\u7269\u7406\u63a5\u53e3\u3001\u96a7\u9053\u548c\u6ce8\u518c\u63a5\u53e3\u3002<\/p>\n<\/li>\n
- \n
\u8f6c\u53d1\u5f15\u64ce：\u57fa\u4e8e MFC \u6761\u76ee\u9ad8\u6548\u514b\u9686\u8f6c\u53d1\u5305\u3002<\/p>\n<\/li>\n
- \n
\u534f\u8bae\u652f\u6301：\u4e0e PIM\/DVMRP \u5b88\u62a4\u8fdb\u7a0b\u534f\u540c\u5de5\u4f5c\u3002<\/p>\n<\/li>\n
- \n
\u63a7\u5236\u63a5\u53e3：\u63d0\u4f9b Netlink\u3001IOCTL\u3001Procfs \u7b49\u7ba1\u7406\u65b9\u5f0f\u3002
\n\u5176\u8bbe\u8ba1\u5e73\u8861\u4e86\u6027\u80fd\u548c\u7075\u6d3b\u6027，\u662f Linux \u591a\u64ad\u8def\u7531\u7684\u57fa\u77f3\u3002<\/p>\n<\/li>\n","protected":false},"excerpt":{"rendered":"\u6587\u7ae0\u6d4f\u89c8\u9605\u8bfb227\u6b21\u3002\u672c\u6587\u6df1\u5165\u5256\u6790\u4e86Linux\u5185\u6838\u4e2dIPv4\u591a\u64ad\u8def\u7531\u7684\u6838\u5fc3\u5b9e\u73b0\u673a\u5236\uff0c\u4e3b\u8981\u5305\u542b\u4ee5\u4e0b\u5173\u952e\u5185\u5bb9\uff1a \u6838\u5fc3\u6570\u636e\u7ed3\u6784 \u591a\u64ad\u8def\u7531\u8868\uff08mr_table\uff09\uff1a\u7ba1\u7406\u865a\u62df\u63a5\u53e3\u8868\u3001\u8f6c\u53d1\u7f13\u5b58\u548c\u672a\u89e3\u6790\u961f\u5217 \u865a\u62df\u63a5\u53e3\uff08vif_device\uff09\uff1a\u652f\u6301\u7269\u7406\u3001\u96a7\u9053\u548c\u6ce8\u518c\u4e09\u79cd\u63a5\u53e3\u7c7b\u578b \u8f6c\u53d1\u7f13\u5b58\uff08mfc_cache\uff09\uff1a\u5b58\u50a8\u6e90\/\u7ec4\u5730\u5740\u3001\u8f93\u5165\u63a5\u53e3\u548c\u8f93\u51faTTL\u6620\u5c04 \u6570\u636e\u5305\u8f6c\u53d1\u6d41\u7a0b \u5feb\u901f\u5339\u914d\uff1a\u54c8\u5e0c\u8868\u67e5\u627eMFC\u6761\u76ee TTL\u6821\u9a8c\uff1a\u8fc7\u6ee4\u65e0\u6548\u51fa\u53e3\u63a5\u53e3 \u667a\u80fd\u514b\u9686\uff1a\u4ec5\u590d\u5236\u5305\u5934\u51cf\u5c11\u5f00\u9500 \u591a\u63a5\u53e3\u8f6c\u53d1\uff1a\u652f\u6301\u96a7\u9053\u5c01\u88c5\u548c\u76f4\u63a5\u53d1\u9001 \u63a7\u5236\u5e73\u9762\u8bbe\u8ba1 \u52a8\u6001\u5b66\u4e60\uff1a\u901a\u8fc7PIM\/IGMP\u6d88\u606f\u81ea\u52a8\u521b\u5efa<\/p>\n","protected":false},"author":2,"featured_media":46958,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[174,1084,50,78],"topic":[],"class_list":["post-46960","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-server","tag-c","tag-linux","tag-50","tag-78"],"yoast_head":"\n
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