// SPDX-License-Identifier: GPL-2.0-or-later /* * INET An implementation of the TCP/IP protocol suite for the LINUX * operating system. INET is implemented using the BSD Socket * interface as the means of communication with the user level. * * ROUTE - implementation of the IP router. * * Authors: Ross Biro * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> * Alan Cox, <gw4pts@gw4pts.ampr.org> * Linus Torvalds, <Linus.Torvalds@helsinki.fi> * Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> * * Fixes: * Alan Cox : Verify area fixes. * Alan Cox : cli() protects routing changes * Rui Oliveira : ICMP routing table updates * (rco@di.uminho.pt) Routing table insertion and update * Linus Torvalds : Rewrote bits to be sensible * Alan Cox : Added BSD route gw semantics * Alan Cox : Super /proc >4K * Alan Cox : MTU in route table * Alan Cox : MSS actually. Also added the window * clamper. * Sam Lantinga : Fixed route matching in rt_del() * Alan Cox : Routing cache support. * Alan Cox : Removed compatibility cruft. * Alan Cox : RTF_REJECT support. * Alan Cox : TCP irtt support. * Jonathan Naylor : Added Metric support. * Miquel van Smoorenburg : BSD API fixes. * Miquel van Smoorenburg : Metrics. * Alan Cox : Use __u32 properly * Alan Cox : Aligned routing errors more closely with BSD * our system is still very different. * Alan Cox : Faster /proc handling * Alexey Kuznetsov : Massive rework to support tree based routing, * routing caches and better behaviour. * * Olaf Erb : irtt wasn't being copied right. * Bjorn Ekwall : Kerneld route support. * Alan Cox : Multicast fixed (I hope) * Pavel Krauz : Limited broadcast fixed * Mike McLagan : Routing by source * Alexey Kuznetsov : End of old history. Split to fib.c and * route.c and rewritten from scratch. * Andi Kleen : Load-limit warning messages. * Vitaly E. Lavrov : Transparent proxy revived after year coma. * Vitaly E. Lavrov : Race condition in ip_route_input_slow. * Tobias Ringstrom : Uninitialized res.type in ip_route_output_slow. * Vladimir V. Ivanov : IP rule info (flowid) is really useful. * Marc Boucher : routing by fwmark * Robert Olsson : Added rt_cache statistics * Arnaldo C. Melo : Convert proc stuff to seq_file * Eric Dumazet : hashed spinlocks and rt_check_expire() fixes. * Ilia Sotnikov : Ignore TOS on PMTUD and Redirect * Ilia Sotnikov : Removed TOS from hash calculations */ #define pr_fmt(fmt) "IPv4: " fmt #include <linux/module.h> #include <linux/uaccess.h> #include <linux/bitops.h> #include <linux/types.h> #include <linux/kernel.h> #include <linux/mm.h> #include <linux/memblock.h> #include <linux/string.h> #include <linux/socket.h> #include <linux/sockios.h> #include <linux/errno.h> #include <linux/in.h> #include <linux/inet.h> #include <linux/netdevice.h> #include <linux/proc_fs.h> #include <linux/init.h> #include <linux/skbuff.h> #include <linux/inetdevice.h> #include <linux/igmp.h> #include <linux/pkt_sched.h> #include <linux/mroute.h> #include <linux/netfilter_ipv4.h> #include <linux/random.h> #include <linux/rcupdate.h> #include <linux/times.h> #include <linux/slab.h> #include <linux/jhash.h> #include <net/dst.h> #include <net/dst_metadata.h> #include <net/net_namespace.h> #include <net/protocol.h> #include <net/ip.h> #include <net/route.h> #include <net/inetpeer.h> #include <net/sock.h> #include <net/ip_fib.h> #include <net/nexthop.h> #include <net/arp.h> #include <net/tcp.h> #include <net/icmp.h> #include <net/xfrm.h> #include <net/lwtunnel.h> #include <net/netevent.h> #include <net/rtnetlink.h> #ifdef CONFIG_SYSCTL #include <linux/sysctl.h> #endif #include <net/secure_seq.h> #include <net/ip_tunnels.h> #include <net/l3mdev.h> #include "fib_lookup.h" #define RT_FL_TOS(oldflp4) \ <------>((oldflp4)->flowi4_tos & (IPTOS_RT_MASK | RTO_ONLINK)) #define RT_GC_TIMEOUT (300*HZ) static int ip_rt_max_size; static int ip_rt_redirect_number __read_mostly = 9; static int ip_rt_redirect_load __read_mostly = HZ / 50; static int ip_rt_redirect_silence __read_mostly = ((HZ / 50) << (9 + 1)); static int ip_rt_error_cost __read_mostly = HZ; static int ip_rt_error_burst __read_mostly = 5 * HZ; static int ip_rt_mtu_expires __read_mostly = 10 * 60 * HZ; static u32 ip_rt_min_pmtu __read_mostly = 512 + 20 + 20; static int ip_rt_min_advmss __read_mostly = 256; static int ip_rt_gc_timeout __read_mostly = RT_GC_TIMEOUT; /* * Interface to generic destination cache. */ static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie); static unsigned int ipv4_default_advmss(const struct dst_entry *dst); static unsigned int ipv4_mtu(const struct dst_entry *dst); static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst); static void ipv4_link_failure(struct sk_buff *skb); static void ip_rt_update_pmtu(struct dst_entry *dst, struct sock *sk, <------><------><------><------><------> struct sk_buff *skb, u32 mtu, <------><------><------><------><------> bool confirm_neigh); static void ip_do_redirect(struct dst_entry *dst, struct sock *sk, <------><------><------><------><------>struct sk_buff *skb); static void ipv4_dst_destroy(struct dst_entry *dst); static u32 *ipv4_cow_metrics(struct dst_entry *dst, unsigned long old) { <------>WARN_ON(1); <------>return NULL; } static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst, <------><------><------><------><------> struct sk_buff *skb, <------><------><------><------><------> const void *daddr); static void ipv4_confirm_neigh(const struct dst_entry *dst, const void *daddr); static struct dst_ops ipv4_dst_ops = { <------>.family = AF_INET, <------>.check = ipv4_dst_check, <------>.default_advmss = ipv4_default_advmss, <------>.mtu = ipv4_mtu, <------>.cow_metrics = ipv4_cow_metrics, <------>.destroy = ipv4_dst_destroy, <------>.negative_advice = ipv4_negative_advice, <------>.link_failure = ipv4_link_failure, <------>.update_pmtu = ip_rt_update_pmtu, <------>.redirect = ip_do_redirect, <------>.local_out = __ip_local_out, <------>.neigh_lookup = ipv4_neigh_lookup, <------>.confirm_neigh = ipv4_confirm_neigh, }; #define ECN_OR_COST(class) TC_PRIO_##class const __u8 ip_tos2prio[16] = { <------>TC_PRIO_BESTEFFORT, <------>ECN_OR_COST(BESTEFFORT), <------>TC_PRIO_BESTEFFORT, <------>ECN_OR_COST(BESTEFFORT), <------>TC_PRIO_BULK, <------>ECN_OR_COST(BULK), <------>TC_PRIO_BULK, <------>ECN_OR_COST(BULK), <------>TC_PRIO_INTERACTIVE, <------>ECN_OR_COST(INTERACTIVE), <------>TC_PRIO_INTERACTIVE, <------>ECN_OR_COST(INTERACTIVE), <------>TC_PRIO_INTERACTIVE_BULK, <------>ECN_OR_COST(INTERACTIVE_BULK), <------>TC_PRIO_INTERACTIVE_BULK, <------>ECN_OR_COST(INTERACTIVE_BULK) }; EXPORT_SYMBOL(ip_tos2prio); static DEFINE_PER_CPU(struct rt_cache_stat, rt_cache_stat); #define RT_CACHE_STAT_INC(field) raw_cpu_inc(rt_cache_stat.field) #ifdef CONFIG_PROC_FS static void *rt_cache_seq_start(struct seq_file *seq, loff_t *pos) { <------>if (*pos) <------><------>return NULL; <------>return SEQ_START_TOKEN; } static void *rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos) { <------>++*pos; <------>return NULL; } static void rt_cache_seq_stop(struct seq_file *seq, void *v) { } static int rt_cache_seq_show(struct seq_file *seq, void *v) { <------>if (v == SEQ_START_TOKEN) <------><------>seq_printf(seq, "%-127s\n", <------><------><------> "Iface\tDestination\tGateway \tFlags\t\tRefCnt\tUse\t" <------><------><------> "Metric\tSource\t\tMTU\tWindow\tIRTT\tTOS\tHHRef\t" <------><------><------> "HHUptod\tSpecDst"); <------>return 0; } static const struct seq_operations rt_cache_seq_ops = { <------>.start = rt_cache_seq_start, <------>.next = rt_cache_seq_next, <------>.stop = rt_cache_seq_stop, <------>.show = rt_cache_seq_show, }; static int rt_cache_seq_open(struct inode *inode, struct file *file) { <------>return seq_open(file, &rt_cache_seq_ops); } static const struct proc_ops rt_cache_proc_ops = { <------>.proc_open = rt_cache_seq_open, <------>.proc_read = seq_read, <------>.proc_lseek = seq_lseek, <------>.proc_release = seq_release, }; static void *rt_cpu_seq_start(struct seq_file *seq, loff_t *pos) { <------>int cpu; <------>if (*pos == 0) <------><------>return SEQ_START_TOKEN; <------>for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) { <------><------>if (!cpu_possible(cpu)) <------><------><------>continue; <------><------>*pos = cpu+1; <------><------>return &per_cpu(rt_cache_stat, cpu); <------>} <------>return NULL; } static void *rt_cpu_seq_next(struct seq_file *seq, void *v, loff_t *pos) { <------>int cpu; <------>for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) { <------><------>if (!cpu_possible(cpu)) <------><------><------>continue; <------><------>*pos = cpu+1; <------><------>return &per_cpu(rt_cache_stat, cpu); <------>} <------>(*pos)++; <------>return NULL; } static void rt_cpu_seq_stop(struct seq_file *seq, void *v) { } static int rt_cpu_seq_show(struct seq_file *seq, void *v) { <------>struct rt_cache_stat *st = v; <------>if (v == SEQ_START_TOKEN) { <------><------>seq_printf(seq, "entries in_hit in_slow_tot in_slow_mc in_no_route in_brd in_martian_dst in_martian_src out_hit out_slow_tot out_slow_mc gc_total gc_ignored gc_goal_miss gc_dst_overflow in_hlist_search out_hlist_search\n"); <------><------>return 0; <------>} <------>seq_printf(seq,"%08x %08x %08x %08x %08x %08x %08x %08x " <------><------> " %08x %08x %08x %08x %08x %08x %08x %08x %08x \n", <------><------> dst_entries_get_slow(&ipv4_dst_ops), <------><------> 0, /* st->in_hit */ <------><------> st->in_slow_tot, <------><------> st->in_slow_mc, <------><------> st->in_no_route, <------><------> st->in_brd, <------><------> st->in_martian_dst, <------><------> st->in_martian_src, <------><------> 0, /* st->out_hit */ <------><------> st->out_slow_tot, <------><------> st->out_slow_mc, <------><------> 0, /* st->gc_total */ <------><------> 0, /* st->gc_ignored */ <------><------> 0, /* st->gc_goal_miss */ <------><------> 0, /* st->gc_dst_overflow */ <------><------> 0, /* st->in_hlist_search */ <------><------> 0 /* st->out_hlist_search */ <------><------>); <------>return 0; } static const struct seq_operations rt_cpu_seq_ops = { <------>.start = rt_cpu_seq_start, <------>.next = rt_cpu_seq_next, <------>.stop = rt_cpu_seq_stop, <------>.show = rt_cpu_seq_show, }; static int rt_cpu_seq_open(struct inode *inode, struct file *file) { <------>return seq_open(file, &rt_cpu_seq_ops); } static const struct proc_ops rt_cpu_proc_ops = { <------>.proc_open = rt_cpu_seq_open, <------>.proc_read = seq_read, <------>.proc_lseek = seq_lseek, <------>.proc_release = seq_release, }; #ifdef CONFIG_IP_ROUTE_CLASSID static int rt_acct_proc_show(struct seq_file *m, void *v) { <------>struct ip_rt_acct *dst, *src; <------>unsigned int i, j; <------>dst = kcalloc(256, sizeof(struct ip_rt_acct), GFP_KERNEL); <------>if (!dst) <------><------>return -ENOMEM; <------>for_each_possible_cpu(i) { <------><------>src = (struct ip_rt_acct *)per_cpu_ptr(ip_rt_acct, i); <------><------>for (j = 0; j < 256; j++) { <------><------><------>dst[j].o_bytes += src[j].o_bytes; <------><------><------>dst[j].o_packets += src[j].o_packets; <------><------><------>dst[j].i_bytes += src[j].i_bytes; <------><------><------>dst[j].i_packets += src[j].i_packets; <------><------>} <------>} <------>seq_write(m, dst, 256 * sizeof(struct ip_rt_acct)); <------>kfree(dst); <------>return 0; } #endif static int __net_init ip_rt_do_proc_init(struct net *net) { <------>struct proc_dir_entry *pde; <------>pde = proc_create("rt_cache", 0444, net->proc_net, <------><------><------> &rt_cache_proc_ops); <------>if (!pde) <------><------>goto err1; <------>pde = proc_create("rt_cache", 0444, <------><------><------> net->proc_net_stat, &rt_cpu_proc_ops); <------>if (!pde) <------><------>goto err2; #ifdef CONFIG_IP_ROUTE_CLASSID <------>pde = proc_create_single("rt_acct", 0, net->proc_net, <------><------><------>rt_acct_proc_show); <------>if (!pde) <------><------>goto err3; #endif <------>return 0; #ifdef CONFIG_IP_ROUTE_CLASSID err3: <------>remove_proc_entry("rt_cache", net->proc_net_stat); #endif err2: <------>remove_proc_entry("rt_cache", net->proc_net); err1: <------>return -ENOMEM; } static void __net_exit ip_rt_do_proc_exit(struct net *net) { <------>remove_proc_entry("rt_cache", net->proc_net_stat); <------>remove_proc_entry("rt_cache", net->proc_net); #ifdef CONFIG_IP_ROUTE_CLASSID <------>remove_proc_entry("rt_acct", net->proc_net); #endif } static struct pernet_operations ip_rt_proc_ops __net_initdata = { <------>.init = ip_rt_do_proc_init, <------>.exit = ip_rt_do_proc_exit, }; static int __init ip_rt_proc_init(void) { <------>return register_pernet_subsys(&ip_rt_proc_ops); } #else static inline int ip_rt_proc_init(void) { <------>return 0; } #endif /* CONFIG_PROC_FS */ static inline bool rt_is_expired(const struct rtable *rth) { <------>return rth->rt_genid != rt_genid_ipv4(dev_net(rth->dst.dev)); } void rt_cache_flush(struct net *net) { <------>rt_genid_bump_ipv4(net); } static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst, <------><------><------><------><------> struct sk_buff *skb, <------><------><------><------><------> const void *daddr) { <------>const struct rtable *rt = container_of(dst, struct rtable, dst); <------>struct net_device *dev = dst->dev; <------>struct neighbour *n; <------>rcu_read_lock_bh(); <------>if (likely(rt->rt_gw_family == AF_INET)) { <------><------>n = ip_neigh_gw4(dev, rt->rt_gw4); <------>} else if (rt->rt_gw_family == AF_INET6) { <------><------>n = ip_neigh_gw6(dev, &rt->rt_gw6); } else { <------><------>__be32 pkey; <------><------>pkey = skb ? ip_hdr(skb)->daddr : *((__be32 *) daddr); <------><------>n = ip_neigh_gw4(dev, pkey); <------>} <------>if (!IS_ERR(n) && !refcount_inc_not_zero(&n->refcnt)) <------><------>n = NULL; <------>rcu_read_unlock_bh(); <------>return n; } static void ipv4_confirm_neigh(const struct dst_entry *dst, const void *daddr) { <------>const struct rtable *rt = container_of(dst, struct rtable, dst); <------>struct net_device *dev = dst->dev; <------>const __be32 *pkey = daddr; <------>if (rt->rt_gw_family == AF_INET) { <------><------>pkey = (const __be32 *)&rt->rt_gw4; <------>} else if (rt->rt_gw_family == AF_INET6) { <------><------>return __ipv6_confirm_neigh_stub(dev, &rt->rt_gw6); <------>} else if (!daddr || <------><------> (rt->rt_flags & <------><------> (RTCF_MULTICAST | RTCF_BROADCAST | RTCF_LOCAL))) { <------><------>return; <------>} <------>__ipv4_confirm_neigh(dev, *(__force u32 *)pkey); } /* Hash tables of size 2048..262144 depending on RAM size. * Each bucket uses 8 bytes. */ static u32 ip_idents_mask __read_mostly; static atomic_t *ip_idents __read_mostly; static u32 *ip_tstamps __read_mostly; /* In order to protect privacy, we add a perturbation to identifiers * if one generator is seldom used. This makes hard for an attacker * to infer how many packets were sent between two points in time. */ u32 ip_idents_reserve(u32 hash, int segs) { <------>u32 bucket, old, now = (u32)jiffies; <------>atomic_t *p_id; <------>u32 *p_tstamp; <------>u32 delta = 0; <------>bucket = hash & ip_idents_mask; <------>p_tstamp = ip_tstamps + bucket; <------>p_id = ip_idents + bucket; <------>old = READ_ONCE(*p_tstamp); <------>if (old != now && cmpxchg(p_tstamp, old, now) == old) <------><------>delta = prandom_u32_max(now - old); <------>/* If UBSAN reports an error there, please make sure your compiler <------> * supports -fno-strict-overflow before reporting it that was a bug <------> * in UBSAN, and it has been fixed in GCC-8. <------> */ <------>return atomic_add_return(segs + delta, p_id) - segs; } EXPORT_SYMBOL(ip_idents_reserve); void __ip_select_ident(struct net *net, struct iphdr *iph, int segs) { <------>u32 hash, id; <------>/* Note the following code is not safe, but this is okay. */ <------>if (unlikely(siphash_key_is_zero(&net->ipv4.ip_id_key))) <------><------>get_random_bytes(&net->ipv4.ip_id_key, <------><------><------><------> sizeof(net->ipv4.ip_id_key)); <------>hash = siphash_3u32((__force u32)iph->daddr, <------><------><------> (__force u32)iph->saddr, <------><------><------> iph->protocol, <------><------><------> &net->ipv4.ip_id_key); <------>id = ip_idents_reserve(hash, segs); <------>iph->id = htons(id); } EXPORT_SYMBOL(__ip_select_ident); static void ip_rt_fix_tos(struct flowi4 *fl4) { <------>__u8 tos = RT_FL_TOS(fl4); <------>fl4->flowi4_tos = tos & IPTOS_RT_MASK; <------>fl4->flowi4_scope = tos & RTO_ONLINK ? <------><------><------> RT_SCOPE_LINK : RT_SCOPE_UNIVERSE; } static void __build_flow_key(const struct net *net, struct flowi4 *fl4, <------><------><------> const struct sock *sk, <------><------><------> const struct iphdr *iph, <------><------><------> int oif, u8 tos, <------><------><------> u8 prot, u32 mark, int flow_flags) { <------>if (sk) { <------><------>const struct inet_sock *inet = inet_sk(sk); <------><------>oif = sk->sk_bound_dev_if; <------><------>mark = sk->sk_mark; <------><------>tos = RT_CONN_FLAGS(sk); <------><------>prot = inet->hdrincl ? IPPROTO_RAW : sk->sk_protocol; <------>} <------>flowi4_init_output(fl4, oif, mark, tos, <------><------><------> RT_SCOPE_UNIVERSE, prot, <------><------><------> flow_flags, <------><------><------> iph->daddr, iph->saddr, 0, 0, <------><------><------> sock_net_uid(net, sk)); } static void build_skb_flow_key(struct flowi4 *fl4, const struct sk_buff *skb, <------><------><------> const struct sock *sk) { <------>const struct net *net = dev_net(skb->dev); <------>const struct iphdr *iph = ip_hdr(skb); <------>int oif = skb->dev->ifindex; <------>u8 tos = RT_TOS(iph->tos); <------>u8 prot = iph->protocol; <------>u32 mark = skb->mark; <------>__build_flow_key(net, fl4, sk, iph, oif, tos, prot, mark, 0); } static void build_sk_flow_key(struct flowi4 *fl4, const struct sock *sk) { <------>const struct inet_sock *inet = inet_sk(sk); <------>const struct ip_options_rcu *inet_opt; <------>__be32 daddr = inet->inet_daddr; <------>rcu_read_lock(); <------>inet_opt = rcu_dereference(inet->inet_opt); <------>if (inet_opt && inet_opt->opt.srr) <------><------>daddr = inet_opt->opt.faddr; <------>flowi4_init_output(fl4, sk->sk_bound_dev_if, sk->sk_mark, <------><------><------> RT_CONN_FLAGS(sk), RT_SCOPE_UNIVERSE, <------><------><------> inet->hdrincl ? IPPROTO_RAW : sk->sk_protocol, <------><------><------> inet_sk_flowi_flags(sk), <------><------><------> daddr, inet->inet_saddr, 0, 0, sk->sk_uid); <------>rcu_read_unlock(); } static void ip_rt_build_flow_key(struct flowi4 *fl4, const struct sock *sk, <------><------><------><------> const struct sk_buff *skb) { <------>if (skb) <------><------>build_skb_flow_key(fl4, skb, sk); <------>else <------><------>build_sk_flow_key(fl4, sk); } static DEFINE_SPINLOCK(fnhe_lock); static void fnhe_flush_routes(struct fib_nh_exception *fnhe) { <------>struct rtable *rt; <------>rt = rcu_dereference(fnhe->fnhe_rth_input); <------>if (rt) { <------><------>RCU_INIT_POINTER(fnhe->fnhe_rth_input, NULL); <------><------>dst_dev_put(&rt->dst); <------><------>dst_release(&rt->dst); <------>} <------>rt = rcu_dereference(fnhe->fnhe_rth_output); <------>if (rt) { <------><------>RCU_INIT_POINTER(fnhe->fnhe_rth_output, NULL); <------><------>dst_dev_put(&rt->dst); <------><------>dst_release(&rt->dst); <------>} } static void fnhe_remove_oldest(struct fnhe_hash_bucket *hash) { <------>struct fib_nh_exception __rcu **fnhe_p, **oldest_p; <------>struct fib_nh_exception *fnhe, *oldest = NULL; <------>for (fnhe_p = &hash->chain; ; fnhe_p = &fnhe->fnhe_next) { <------><------>fnhe = rcu_dereference_protected(*fnhe_p, <------><------><------><------><------><------> lockdep_is_held(&fnhe_lock)); <------><------>if (!fnhe) <------><------><------>break; <------><------>if (!oldest || <------><------> time_before(fnhe->fnhe_stamp, oldest->fnhe_stamp)) { <------><------><------>oldest = fnhe; <------><------><------>oldest_p = fnhe_p; <------><------>} <------>} <------>fnhe_flush_routes(oldest); <------>*oldest_p = oldest->fnhe_next; <------>kfree_rcu(oldest, rcu); } static u32 fnhe_hashfun(__be32 daddr) { <------>static siphash_key_t fnhe_hash_key __read_mostly; <------>u64 hval; <------>net_get_random_once(&fnhe_hash_key, sizeof(fnhe_hash_key)); <------>hval = siphash_1u32((__force u32)daddr, &fnhe_hash_key); <------>return hash_64(hval, FNHE_HASH_SHIFT); } static void fill_route_from_fnhe(struct rtable *rt, struct fib_nh_exception *fnhe) { <------>rt->rt_pmtu = fnhe->fnhe_pmtu; <------>rt->rt_mtu_locked = fnhe->fnhe_mtu_locked; <------>rt->dst.expires = fnhe->fnhe_expires; <------>if (fnhe->fnhe_gw) { <------><------>rt->rt_flags |= RTCF_REDIRECTED; <------><------>rt->rt_uses_gateway = 1; <------><------>rt->rt_gw_family = AF_INET; <------><------>rt->rt_gw4 = fnhe->fnhe_gw; <------>} } static void update_or_create_fnhe(struct fib_nh_common *nhc, __be32 daddr, <------><------><------><------> __be32 gw, u32 pmtu, bool lock, <------><------><------><------> unsigned long expires) { <------>struct fnhe_hash_bucket *hash; <------>struct fib_nh_exception *fnhe; <------>struct rtable *rt; <------>u32 genid, hval; <------>unsigned int i; <------>int depth; <------>genid = fnhe_genid(dev_net(nhc->nhc_dev)); <------>hval = fnhe_hashfun(daddr); <------>spin_lock_bh(&fnhe_lock); <------>hash = rcu_dereference(nhc->nhc_exceptions); <------>if (!hash) { <------><------>hash = kcalloc(FNHE_HASH_SIZE, sizeof(*hash), GFP_ATOMIC); <------><------>if (!hash) <------><------><------>goto out_unlock; <------><------>rcu_assign_pointer(nhc->nhc_exceptions, hash); <------>} <------>hash += hval; <------>depth = 0; <------>for (fnhe = rcu_dereference(hash->chain); fnhe; <------> fnhe = rcu_dereference(fnhe->fnhe_next)) { <------><------>if (fnhe->fnhe_daddr == daddr) <------><------><------>break; <------><------>depth++; <------>} <------>if (fnhe) { <------><------>if (fnhe->fnhe_genid != genid) <------><------><------>fnhe->fnhe_genid = genid; <------><------>if (gw) <------><------><------>fnhe->fnhe_gw = gw; <------><------>if (pmtu) { <------><------><------>fnhe->fnhe_pmtu = pmtu; <------><------><------>fnhe->fnhe_mtu_locked = lock; <------><------>} <------><------>fnhe->fnhe_expires = max(1UL, expires); <------><------>/* Update all cached dsts too */ <------><------>rt = rcu_dereference(fnhe->fnhe_rth_input); <------><------>if (rt) <------><------><------>fill_route_from_fnhe(rt, fnhe); <------><------>rt = rcu_dereference(fnhe->fnhe_rth_output); <------><------>if (rt) <------><------><------>fill_route_from_fnhe(rt, fnhe); <------>} else { <------><------>/* Randomize max depth to avoid some side channels attacks. */ <------><------>int max_depth = FNHE_RECLAIM_DEPTH + <------><------><------><------>prandom_u32_max(FNHE_RECLAIM_DEPTH); <------><------>while (depth > max_depth) { <------><------><------>fnhe_remove_oldest(hash); <------><------><------>depth--; <------><------>} <------><------>fnhe = kzalloc(sizeof(*fnhe), GFP_ATOMIC); <------><------>if (!fnhe) <------><------><------>goto out_unlock; <------><------>fnhe->fnhe_next = hash->chain; <------><------>fnhe->fnhe_genid = genid; <------><------>fnhe->fnhe_daddr = daddr; <------><------>fnhe->fnhe_gw = gw; <------><------>fnhe->fnhe_pmtu = pmtu; <------><------>fnhe->fnhe_mtu_locked = lock; <------><------>fnhe->fnhe_expires = max(1UL, expires); <------><------>rcu_assign_pointer(hash->chain, fnhe); <------><------>/* Exception created; mark the cached routes for the nexthop <------><------> * stale, so anyone caching it rechecks if this exception <------><------> * applies to them. <------><------> */ <------><------>rt = rcu_dereference(nhc->nhc_rth_input); <------><------>if (rt) <------><------><------>rt->dst.obsolete = DST_OBSOLETE_KILL; <------><------>for_each_possible_cpu(i) { <------><------><------>struct rtable __rcu **prt; <------><------><------>prt = per_cpu_ptr(nhc->nhc_pcpu_rth_output, i); <------><------><------>rt = rcu_dereference(*prt); <------><------><------>if (rt) <------><------><------><------>rt->dst.obsolete = DST_OBSOLETE_KILL; <------><------>} <------>} <------>fnhe->fnhe_stamp = jiffies; out_unlock: <------>spin_unlock_bh(&fnhe_lock); } static void __ip_do_redirect(struct rtable *rt, struct sk_buff *skb, struct flowi4 *fl4, <------><------><------> bool kill_route) { <------>__be32 new_gw = icmp_hdr(skb)->un.gateway; <------>__be32 old_gw = ip_hdr(skb)->saddr; <------>struct net_device *dev = skb->dev; <------>struct in_device *in_dev; <------>struct fib_result res; <------>struct neighbour *n; <------>struct net *net; <------>switch (icmp_hdr(skb)->code & 7) { <------>case ICMP_REDIR_NET: <------>case ICMP_REDIR_NETTOS: <------>case ICMP_REDIR_HOST: <------>case ICMP_REDIR_HOSTTOS: <------><------>break; <------>default: <------><------>return; <------>} <------>if (rt->rt_gw_family != AF_INET || rt->rt_gw4 != old_gw) <------><------>return; <------>in_dev = __in_dev_get_rcu(dev); <------>if (!in_dev) <------><------>return; <------>net = dev_net(dev); <------>if (new_gw == old_gw || !IN_DEV_RX_REDIRECTS(in_dev) || <------> ipv4_is_multicast(new_gw) || ipv4_is_lbcast(new_gw) || <------> ipv4_is_zeronet(new_gw)) <------><------>goto reject_redirect; <------>if (!IN_DEV_SHARED_MEDIA(in_dev)) { <------><------>if (!inet_addr_onlink(in_dev, new_gw, old_gw)) <------><------><------>goto reject_redirect; <------><------>if (IN_DEV_SEC_REDIRECTS(in_dev) && ip_fib_check_default(new_gw, dev)) <------><------><------>goto reject_redirect; <------>} else { <------><------>if (inet_addr_type(net, new_gw) != RTN_UNICAST) <------><------><------>goto reject_redirect; <------>} <------>n = __ipv4_neigh_lookup(rt->dst.dev, new_gw); <------>if (!n) <------><------>n = neigh_create(&arp_tbl, &new_gw, rt->dst.dev); <------>if (!IS_ERR(n)) { <------><------>if (!(n->nud_state & NUD_VALID)) { <------><------><------>neigh_event_send(n, NULL); <------><------>} else { <------><------><------>if (fib_lookup(net, fl4, &res, 0) == 0) { <------><------><------><------>struct fib_nh_common *nhc; <------><------><------><------>fib_select_path(net, &res, fl4, skb); <------><------><------><------>nhc = FIB_RES_NHC(res); <------><------><------><------>update_or_create_fnhe(nhc, fl4->daddr, new_gw, <------><------><------><------><------><------>0, false, <------><------><------><------><------><------>jiffies + ip_rt_gc_timeout); <------><------><------>} <------><------><------>if (kill_route) <------><------><------><------>rt->dst.obsolete = DST_OBSOLETE_KILL; <------><------><------>call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, n); <------><------>} <------><------>neigh_release(n); <------>} <------>return; reject_redirect: #ifdef CONFIG_IP_ROUTE_VERBOSE <------>if (IN_DEV_LOG_MARTIANS(in_dev)) { <------><------>const struct iphdr *iph = (const struct iphdr *) skb->data; <------><------>__be32 daddr = iph->daddr; <------><------>__be32 saddr = iph->saddr; <------><------>net_info_ratelimited("Redirect from %pI4 on %s about %pI4 ignored\n" <------><------><------><------> " Advised path = %pI4 -> %pI4\n", <------><------><------><------> &old_gw, dev->name, &new_gw, <------><------><------><------> &saddr, &daddr); <------>} #endif <------>; } static void ip_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb) { <------>struct rtable *rt; <------>struct flowi4 fl4; <------>const struct iphdr *iph = (const struct iphdr *) skb->data; <------>struct net *net = dev_net(skb->dev); <------>int oif = skb->dev->ifindex; <------>u8 tos = RT_TOS(iph->tos); <------>u8 prot = iph->protocol; <------>u32 mark = skb->mark; <------>rt = (struct rtable *) dst; <------>__build_flow_key(net, &fl4, sk, iph, oif, tos, prot, mark, 0); <------>ip_rt_fix_tos(&fl4); <------>__ip_do_redirect(rt, skb, &fl4, true); } static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst) { <------>struct rtable *rt = (struct rtable *)dst; <------>struct dst_entry *ret = dst; <------>if (rt) { <------><------>if (dst->obsolete > 0) { <------><------><------>ip_rt_put(rt); <------><------><------>ret = NULL; <------><------>} else if ((rt->rt_flags & RTCF_REDIRECTED) || <------><------><------> rt->dst.expires) { <------><------><------>ip_rt_put(rt); <------><------><------>ret = NULL; <------><------>} <------>} <------>return ret; } /* * Algorithm: * 1. The first ip_rt_redirect_number redirects are sent * with exponential backoff, then we stop sending them at all, * assuming that the host ignores our redirects. * 2. If we did not see packets requiring redirects * during ip_rt_redirect_silence, we assume that the host * forgot redirected route and start to send redirects again. * * This algorithm is much cheaper and more intelligent than dumb load limiting * in icmp.c. * * NOTE. Do not forget to inhibit load limiting for redirects (redundant) * and "frag. need" (breaks PMTU discovery) in icmp.c. */ void ip_rt_send_redirect(struct sk_buff *skb) { <------>struct rtable *rt = skb_rtable(skb); <------>struct in_device *in_dev; <------>struct inet_peer *peer; <------>struct net *net; <------>int log_martians; <------>int vif; <------>rcu_read_lock(); <------>in_dev = __in_dev_get_rcu(rt->dst.dev); <------>if (!in_dev || !IN_DEV_TX_REDIRECTS(in_dev)) { <------><------>rcu_read_unlock(); <------><------>return; <------>} <------>log_martians = IN_DEV_LOG_MARTIANS(in_dev); <------>vif = l3mdev_master_ifindex_rcu(rt->dst.dev); <------>rcu_read_unlock(); <------>net = dev_net(rt->dst.dev); <------>peer = inet_getpeer_v4(net->ipv4.peers, ip_hdr(skb)->saddr, vif, 1); <------>if (!peer) { <------><------>icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, <------><------><------> rt_nexthop(rt, ip_hdr(skb)->daddr)); <------><------>return; <------>} <------>/* No redirected packets during ip_rt_redirect_silence; <------> * reset the algorithm. <------> */ <------>if (time_after(jiffies, peer->rate_last + ip_rt_redirect_silence)) { <------><------>peer->rate_tokens = 0; <------><------>peer->n_redirects = 0; <------>} <------>/* Too many ignored redirects; do not send anything <------> * set dst.rate_last to the last seen redirected packet. <------> */ <------>if (peer->n_redirects >= ip_rt_redirect_number) { <------><------>peer->rate_last = jiffies; <------><------>goto out_put_peer; <------>} <------>/* Check for load limit; set rate_last to the latest sent <------> * redirect. <------> */ <------>if (peer->n_redirects == 0 || <------> time_after(jiffies, <------><------> (peer->rate_last + <------><------><------>(ip_rt_redirect_load << peer->n_redirects)))) { <------><------>__be32 gw = rt_nexthop(rt, ip_hdr(skb)->daddr); <------><------>icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, gw); <------><------>peer->rate_last = jiffies; <------><------>++peer->n_redirects; #ifdef CONFIG_IP_ROUTE_VERBOSE <------><------>if (log_martians && <------><------> peer->n_redirects == ip_rt_redirect_number) <------><------><------>net_warn_ratelimited("host %pI4/if%d ignores redirects for %pI4 to %pI4\n", <------><------><------><------><------> &ip_hdr(skb)->saddr, inet_iif(skb), <------><------><------><------><------> &ip_hdr(skb)->daddr, &gw); #endif <------>} out_put_peer: <------>inet_putpeer(peer); } static int ip_error(struct sk_buff *skb) { <------>struct rtable *rt = skb_rtable(skb); <------>struct net_device *dev = skb->dev; <------>struct in_device *in_dev; <------>struct inet_peer *peer; <------>unsigned long now; <------>struct net *net; <------>bool send; <------>int code; <------>if (netif_is_l3_master(skb->dev)) { <------><------>dev = __dev_get_by_index(dev_net(skb->dev), IPCB(skb)->iif); <------><------>if (!dev) <------><------><------>goto out; <------>} <------>in_dev = __in_dev_get_rcu(dev); <------>/* IP on this device is disabled. */ <------>if (!in_dev) <------><------>goto out; <------>net = dev_net(rt->dst.dev); <------>if (!IN_DEV_FORWARD(in_dev)) { <------><------>switch (rt->dst.error) { <------><------>case EHOSTUNREACH: <------><------><------>__IP_INC_STATS(net, IPSTATS_MIB_INADDRERRORS); <------><------><------>break; <------><------>case ENETUNREACH: <------><------><------>__IP_INC_STATS(net, IPSTATS_MIB_INNOROUTES); <------><------><------>break; <------><------>} <------><------>goto out; <------>} <------>switch (rt->dst.error) { <------>case EINVAL: <------>default: <------><------>goto out; <------>case EHOSTUNREACH: <------><------>code = ICMP_HOST_UNREACH; <------><------>break; <------>case ENETUNREACH: <------><------>code = ICMP_NET_UNREACH; <------><------>__IP_INC_STATS(net, IPSTATS_MIB_INNOROUTES); <------><------>break; <------>case EACCES: <------><------>code = ICMP_PKT_FILTERED; <------><------>break; <------>} <------>peer = inet_getpeer_v4(net->ipv4.peers, ip_hdr(skb)->saddr, <------><------><------> l3mdev_master_ifindex(skb->dev), 1); <------>send = true; <------>if (peer) { <------><------>now = jiffies; <------><------>peer->rate_tokens += now - peer->rate_last; <------><------>if (peer->rate_tokens > ip_rt_error_burst) <------><------><------>peer->rate_tokens = ip_rt_error_burst; <------><------>peer->rate_last = now; <------><------>if (peer->rate_tokens >= ip_rt_error_cost) <------><------><------>peer->rate_tokens -= ip_rt_error_cost; <------><------>else <------><------><------>send = false; <------><------>inet_putpeer(peer); <------>} <------>if (send) <------><------>icmp_send(skb, ICMP_DEST_UNREACH, code, 0); out: kfree_skb(skb); <------>return 0; } static void __ip_rt_update_pmtu(struct rtable *rt, struct flowi4 *fl4, u32 mtu) { <------>struct dst_entry *dst = &rt->dst; <------>struct net *net = dev_net(dst->dev); <------>struct fib_result res; <------>bool lock = false; <------>u32 old_mtu; <------>if (ip_mtu_locked(dst)) <------><------>return; <------>old_mtu = ipv4_mtu(dst); <------>if (old_mtu < mtu) <------><------>return; <------>if (mtu < ip_rt_min_pmtu) { <------><------>lock = true; <------><------>mtu = min(old_mtu, ip_rt_min_pmtu); <------>} <------>if (rt->rt_pmtu == mtu && !lock && <------> time_before(jiffies, dst->expires - ip_rt_mtu_expires / 2)) <------><------>return; <------>rcu_read_lock(); <------>if (fib_lookup(net, fl4, &res, 0) == 0) { <------><------>struct fib_nh_common *nhc; <------><------>fib_select_path(net, &res, fl4, NULL); <------><------>nhc = FIB_RES_NHC(res); <------><------>update_or_create_fnhe(nhc, fl4->daddr, 0, mtu, lock, <------><------><------><------> jiffies + ip_rt_mtu_expires); <------>} <------>rcu_read_unlock(); } static void ip_rt_update_pmtu(struct dst_entry *dst, struct sock *sk, <------><------><------> struct sk_buff *skb, u32 mtu, <------><------><------> bool confirm_neigh) { <------>struct rtable *rt = (struct rtable *) dst; <------>struct flowi4 fl4; <------>ip_rt_build_flow_key(&fl4, sk, skb); <------>ip_rt_fix_tos(&fl4); <------>/* Don't make lookup fail for bridged encapsulations */ <------>if (skb && netif_is_any_bridge_port(skb->dev)) <------><------>fl4.flowi4_oif = 0; <------>__ip_rt_update_pmtu(rt, &fl4, mtu); } void ipv4_update_pmtu(struct sk_buff *skb, struct net *net, u32 mtu, <------><------> int oif, u8 protocol) { <------>const struct iphdr *iph = (const struct iphdr *)skb->data; <------>struct flowi4 fl4; <------>struct rtable *rt; <------>u32 mark = IP4_REPLY_MARK(net, skb->mark); <------>__build_flow_key(net, &fl4, NULL, iph, oif, <------><------><------> RT_TOS(iph->tos), protocol, mark, 0); <------>rt = __ip_route_output_key(net, &fl4); <------>if (!IS_ERR(rt)) { <------><------>__ip_rt_update_pmtu(rt, &fl4, mtu); <------><------>ip_rt_put(rt); <------>} } EXPORT_SYMBOL_GPL(ipv4_update_pmtu); static void __ipv4_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, u32 mtu) { <------>const struct iphdr *iph = (const struct iphdr *)skb->data; <------>struct flowi4 fl4; <------>struct rtable *rt; <------>__build_flow_key(sock_net(sk), &fl4, sk, iph, 0, 0, 0, 0, 0); <------>if (!fl4.flowi4_mark) <------><------>fl4.flowi4_mark = IP4_REPLY_MARK(sock_net(sk), skb->mark); <------>rt = __ip_route_output_key(sock_net(sk), &fl4); <------>if (!IS_ERR(rt)) { <------><------>__ip_rt_update_pmtu(rt, &fl4, mtu); <------><------>ip_rt_put(rt); <------>} } void ipv4_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, u32 mtu) { <------>const struct iphdr *iph = (const struct iphdr *)skb->data; <------>struct flowi4 fl4; <------>struct rtable *rt; <------>struct dst_entry *odst = NULL; <------>bool new = false; <------>struct net *net = sock_net(sk); <------>bh_lock_sock(sk); <------>if (!ip_sk_accept_pmtu(sk)) <------><------>goto out; <------>odst = sk_dst_get(sk); <------>if (sock_owned_by_user(sk) || !odst) { <------><------>__ipv4_sk_update_pmtu(skb, sk, mtu); <------><------>goto out; <------>} <------>__build_flow_key(net, &fl4, sk, iph, 0, 0, 0, 0, 0); <------>rt = (struct rtable *)odst; <------>if (odst->obsolete && !odst->ops->check(odst, 0)) { <------><------>rt = ip_route_output_flow(sock_net(sk), &fl4, sk); <------><------>if (IS_ERR(rt)) <------><------><------>goto out; <------><------>new = true; <------>} else { <------><------>ip_rt_fix_tos(&fl4); <------>} <------>__ip_rt_update_pmtu((struct rtable *)xfrm_dst_path(&rt->dst), &fl4, mtu); <------>if (!dst_check(&rt->dst, 0)) { <------><------>if (new) <------><------><------>dst_release(&rt->dst); <------><------>rt = ip_route_output_flow(sock_net(sk), &fl4, sk); <------><------>if (IS_ERR(rt)) <------><------><------>goto out; <------><------>new = true; <------>} <------>if (new) <------><------>sk_dst_set(sk, &rt->dst); out: <------>bh_unlock_sock(sk); <------>dst_release(odst); } EXPORT_SYMBOL_GPL(ipv4_sk_update_pmtu); void ipv4_redirect(struct sk_buff *skb, struct net *net, <------><------> int oif, u8 protocol) { <------>const struct iphdr *iph = (const struct iphdr *)skb->data; <------>struct flowi4 fl4; <------>struct rtable *rt; <------>__build_flow_key(net, &fl4, NULL, iph, oif, <------><------><------> RT_TOS(iph->tos), protocol, 0, 0); <------>rt = __ip_route_output_key(net, &fl4); <------>if (!IS_ERR(rt)) { <------><------>__ip_do_redirect(rt, skb, &fl4, false); <------><------>ip_rt_put(rt); <------>} } EXPORT_SYMBOL_GPL(ipv4_redirect); void ipv4_sk_redirect(struct sk_buff *skb, struct sock *sk) { <------>const struct iphdr *iph = (const struct iphdr *)skb->data; <------>struct flowi4 fl4; <------>struct rtable *rt; <------>struct net *net = sock_net(sk); <------>__build_flow_key(net, &fl4, sk, iph, 0, 0, 0, 0, 0); <------>rt = __ip_route_output_key(net, &fl4); <------>if (!IS_ERR(rt)) { <------><------>__ip_do_redirect(rt, skb, &fl4, false); <------><------>ip_rt_put(rt); <------>} } EXPORT_SYMBOL_GPL(ipv4_sk_redirect); static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie) { <------>struct rtable *rt = (struct rtable *) dst; <------>/* All IPV4 dsts are created with ->obsolete set to the value <------> * DST_OBSOLETE_FORCE_CHK which forces validation calls down <------> * into this function always. <------> * <------> * When a PMTU/redirect information update invalidates a route, <------> * this is indicated by setting obsolete to DST_OBSOLETE_KILL or <------> * DST_OBSOLETE_DEAD. <------> */ <------>if (dst->obsolete != DST_OBSOLETE_FORCE_CHK || rt_is_expired(rt)) <------><------>return NULL; <------>return dst; } static void ipv4_send_dest_unreach(struct sk_buff *skb) { <------>struct ip_options opt; <------>int res; <------>/* Recompile ip options since IPCB may not be valid anymore. <------> * Also check we have a reasonable ipv4 header. <------> */ <------>if (!pskb_network_may_pull(skb, sizeof(struct iphdr)) || <------> ip_hdr(skb)->version != 4 || ip_hdr(skb)->ihl < 5) <------><------>return; <------>memset(&opt, 0, sizeof(opt)); <------>if (ip_hdr(skb)->ihl > 5) { <------><------>if (!pskb_network_may_pull(skb, ip_hdr(skb)->ihl * 4)) <------><------><------>return; <------><------>opt.optlen = ip_hdr(skb)->ihl * 4 - sizeof(struct iphdr); <------><------>rcu_read_lock(); <------><------>res = __ip_options_compile(dev_net(skb->dev), &opt, skb, NULL); <------><------>rcu_read_unlock(); <------><------>if (res) <------><------><------>return; <------>} <------>__icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0, &opt); } static void ipv4_link_failure(struct sk_buff *skb) { <------>struct rtable *rt; <------>ipv4_send_dest_unreach(skb); <------>rt = skb_rtable(skb); <------>if (rt) <------><------>dst_set_expires(&rt->dst, 0); } static int ip_rt_bug(struct net *net, struct sock *sk, struct sk_buff *skb) { <------>pr_debug("%s: %pI4 -> %pI4, %s\n", <------><------> __func__, &ip_hdr(skb)->saddr, &ip_hdr(skb)->daddr, <------><------> skb->dev ? skb->dev->name : "?"); <------>kfree_skb(skb); <------>WARN_ON(1); <------>return 0; } /* We do not cache source address of outgoing interface, because it is used only by IP RR, TS and SRR options, so that it out of fast path. BTW remember: "addr" is allowed to be not aligned in IP options! */ void ip_rt_get_source(u8 *addr, struct sk_buff *skb, struct rtable *rt) { <------>__be32 src; <------>if (rt_is_output_route(rt)) <------><------>src = ip_hdr(skb)->saddr; <------>else { <------><------>struct fib_result res; <------><------>struct iphdr *iph = ip_hdr(skb); <------><------>struct flowi4 fl4 = { <------><------><------>.daddr = iph->daddr, <------><------><------>.saddr = iph->saddr, <------><------><------>.flowi4_tos = RT_TOS(iph->tos), <------><------><------>.flowi4_oif = rt->dst.dev->ifindex, <------><------><------>.flowi4_iif = skb->dev->ifindex, <------><------><------>.flowi4_mark = skb->mark, <------><------>}; <------><------>rcu_read_lock(); <------><------>if (fib_lookup(dev_net(rt->dst.dev), &fl4, &res, 0) == 0) <------><------><------>src = fib_result_prefsrc(dev_net(rt->dst.dev), &res); <------><------>else <------><------><------>src = inet_select_addr(rt->dst.dev, <------><------><------><------><------> rt_nexthop(rt, iph->daddr), <------><------><------><------><------> RT_SCOPE_UNIVERSE); <------><------>rcu_read_unlock(); <------>} <------>memcpy(addr, &src, 4); } #ifdef CONFIG_IP_ROUTE_CLASSID static void set_class_tag(struct rtable *rt, u32 tag) { <------>if (!(rt->dst.tclassid & 0xFFFF)) <------><------>rt->dst.tclassid |= tag & 0xFFFF; <------>if (!(rt->dst.tclassid & 0xFFFF0000)) <------><------>rt->dst.tclassid |= tag & 0xFFFF0000; } #endif static unsigned int ipv4_default_advmss(const struct dst_entry *dst) { <------>unsigned int header_size = sizeof(struct tcphdr) + sizeof(struct iphdr); <------>unsigned int advmss = max_t(unsigned int, ipv4_mtu(dst) - header_size, <------><------><------><------> ip_rt_min_advmss); <------>return min(advmss, IPV4_MAX_PMTU - header_size); } static unsigned int ipv4_mtu(const struct dst_entry *dst) { <------>const struct rtable *rt = (const struct rtable *)dst; <------>unsigned int mtu = rt->rt_pmtu; <------>if (!mtu || time_after_eq(jiffies, rt->dst.expires)) <------><------>mtu = dst_metric_raw(dst, RTAX_MTU); <------>if (mtu) <------><------>goto out; <------>mtu = READ_ONCE(dst->dev->mtu); <------>if (unlikely(ip_mtu_locked(dst))) { <------><------>if (rt->rt_uses_gateway && mtu > 576) <------><------><------>mtu = 576; <------>} out: <------>mtu = min_t(unsigned int, mtu, IP_MAX_MTU); <------>return mtu - lwtunnel_headroom(dst->lwtstate, mtu); } static void ip_del_fnhe(struct fib_nh_common *nhc, __be32 daddr) { <------>struct fnhe_hash_bucket *hash; <------>struct fib_nh_exception *fnhe, __rcu **fnhe_p; <------>u32 hval = fnhe_hashfun(daddr); <------>spin_lock_bh(&fnhe_lock); <------>hash = rcu_dereference_protected(nhc->nhc_exceptions, <------><------><------><------><------> lockdep_is_held(&fnhe_lock)); <------>hash += hval; <------>fnhe_p = &hash->chain; <------>fnhe = rcu_dereference_protected(*fnhe_p, lockdep_is_held(&fnhe_lock)); <------>while (fnhe) { <------><------>if (fnhe->fnhe_daddr == daddr) { <------><------><------>rcu_assign_pointer(*fnhe_p, rcu_dereference_protected( <------><------><------><------>fnhe->fnhe_next, lockdep_is_held(&fnhe_lock))); <------><------><------>/* set fnhe_daddr to 0 to ensure it won't bind with <------><------><------> * new dsts in rt_bind_exception(). <------><------><------> */ <------><------><------>fnhe->fnhe_daddr = 0; <------><------><------>fnhe_flush_routes(fnhe); <------><------><------>kfree_rcu(fnhe, rcu); <------><------><------>break; <------><------>} <------><------>fnhe_p = &fnhe->fnhe_next; <------><------>fnhe = rcu_dereference_protected(fnhe->fnhe_next, <------><------><------><------><------><------> lockdep_is_held(&fnhe_lock)); <------>} <------>spin_unlock_bh(&fnhe_lock); } static struct fib_nh_exception *find_exception(struct fib_nh_common *nhc, <------><------><------><------><------> __be32 daddr) { <------>struct fnhe_hash_bucket *hash = rcu_dereference(nhc->nhc_exceptions); <------>struct fib_nh_exception *fnhe; <------>u32 hval; <------>if (!hash) <------><------>return NULL; <------>hval = fnhe_hashfun(daddr); <------>for (fnhe = rcu_dereference(hash[hval].chain); fnhe; <------> fnhe = rcu_dereference(fnhe->fnhe_next)) { <------><------>if (fnhe->fnhe_daddr == daddr) { <------><------><------>if (fnhe->fnhe_expires && <------><------><------> time_after(jiffies, fnhe->fnhe_expires)) { <------><------><------><------>ip_del_fnhe(nhc, daddr); <------><------><------><------>break; <------><------><------>} <------><------><------>return fnhe; <------><------>} <------>} <------>return NULL; } /* MTU selection: * 1. mtu on route is locked - use it * 2. mtu from nexthop exception * 3. mtu from egress device */ u32 ip_mtu_from_fib_result(struct fib_result *res, __be32 daddr) { <------>struct fib_nh_common *nhc = res->nhc; <------>struct net_device *dev = nhc->nhc_dev; <------>struct fib_info *fi = res->fi; <------>u32 mtu = 0; <------>if (dev_net(dev)->ipv4.sysctl_ip_fwd_use_pmtu || <------> fi->fib_metrics->metrics[RTAX_LOCK - 1] & (1 << RTAX_MTU)) <------><------>mtu = fi->fib_mtu; <------>if (likely(!mtu)) { <------><------>struct fib_nh_exception *fnhe; <------><------>fnhe = find_exception(nhc, daddr); <------><------>if (fnhe && !time_after_eq(jiffies, fnhe->fnhe_expires)) <------><------><------>mtu = fnhe->fnhe_pmtu; <------>} <------>if (likely(!mtu)) <------><------>mtu = min(READ_ONCE(dev->mtu), IP_MAX_MTU); <------>return mtu - lwtunnel_headroom(nhc->nhc_lwtstate, mtu); } static bool rt_bind_exception(struct rtable *rt, struct fib_nh_exception *fnhe, <------><------><------> __be32 daddr, const bool do_cache) { <------>bool ret = false; <------>spin_lock_bh(&fnhe_lock); <------>if (daddr == fnhe->fnhe_daddr) { <------><------>struct rtable __rcu **porig; <------><------>struct rtable *orig; <------><------>int genid = fnhe_genid(dev_net(rt->dst.dev)); <------><------>if (rt_is_input_route(rt)) <------><------><------>porig = &fnhe->fnhe_rth_input; <------><------>else <------><------><------>porig = &fnhe->fnhe_rth_output; <------><------>orig = rcu_dereference(*porig); <------><------>if (fnhe->fnhe_genid != genid) { <------><------><------>fnhe->fnhe_genid = genid; <------><------><------>fnhe->fnhe_gw = 0; <------><------><------>fnhe->fnhe_pmtu = 0; <------><------><------>fnhe->fnhe_expires = 0; <------><------><------>fnhe->fnhe_mtu_locked = false; <------><------><------>fnhe_flush_routes(fnhe); <------><------><------>orig = NULL; <------><------>} <------><------>fill_route_from_fnhe(rt, fnhe); <------><------>if (!rt->rt_gw4) { <------><------><------>rt->rt_gw4 = daddr; <------><------><------>rt->rt_gw_family = AF_INET; <------><------>} <------><------>if (do_cache) { <------><------><------>dst_hold(&rt->dst); <------><------><------>rcu_assign_pointer(*porig, rt); <------><------><------>if (orig) { <------><------><------><------>dst_dev_put(&orig->dst); <------><------><------><------>dst_release(&orig->dst); <------><------><------>} <------><------><------>ret = true; <------><------>} <------><------>fnhe->fnhe_stamp = jiffies; <------>} <------>spin_unlock_bh(&fnhe_lock); <------>return ret; } static bool rt_cache_route(struct fib_nh_common *nhc, struct rtable *rt) { <------>struct rtable *orig, *prev, **p; <------>bool ret = true; <------>if (rt_is_input_route(rt)) { <------><------>p = (struct rtable **)&nhc->nhc_rth_input; <------>} else { <------><------>p = (struct rtable **)raw_cpu_ptr(nhc->nhc_pcpu_rth_output); <------>} <------>orig = *p; <------>/* hold dst before doing cmpxchg() to avoid race condition <------> * on this dst <------> */ <------>dst_hold(&rt->dst); <------>prev = cmpxchg(p, orig, rt); <------>if (prev == orig) { <------><------>if (orig) { <------><------><------>rt_add_uncached_list(orig); <------><------><------>dst_release(&orig->dst); <------><------>} <------>} else { <------><------>dst_release(&rt->dst); <------><------>ret = false; <------>} <------>return ret; } struct uncached_list { <------>spinlock_t lock; <------>struct list_head head; }; static DEFINE_PER_CPU_ALIGNED(struct uncached_list, rt_uncached_list); void rt_add_uncached_list(struct rtable *rt) { <------>struct uncached_list *ul = raw_cpu_ptr(&rt_uncached_list); <------>rt->rt_uncached_list = ul; <------>spin_lock_bh(&ul->lock); <------>list_add_tail(&rt->rt_uncached, &ul->head); <------>spin_unlock_bh(&ul->lock); } void rt_del_uncached_list(struct rtable *rt) { <------>if (!list_empty(&rt->rt_uncached)) { <------><------>struct uncached_list *ul = rt->rt_uncached_list; <------><------>spin_lock_bh(&ul->lock); <------><------>list_del(&rt->rt_uncached); <------><------>spin_unlock_bh(&ul->lock); <------>} } static void ipv4_dst_destroy(struct dst_entry *dst) { <------>struct rtable *rt = (struct rtable *)dst; <------>ip_dst_metrics_put(dst); <------>rt_del_uncached_list(rt); } void rt_flush_dev(struct net_device *dev) { <------>struct rtable *rt; <------>int cpu; <------>for_each_possible_cpu(cpu) { <------><------>struct uncached_list *ul = &per_cpu(rt_uncached_list, cpu); <------><------>spin_lock_bh(&ul->lock); <------><------>list_for_each_entry(rt, &ul->head, rt_uncached) { <------><------><------>if (rt->dst.dev != dev) <------><------><------><------>continue; <------><------><------>rt->dst.dev = blackhole_netdev; <------><------><------>dev_hold(rt->dst.dev); <------><------><------>dev_put(dev); <------><------>} <------><------>spin_unlock_bh(&ul->lock); <------>} } static bool rt_cache_valid(const struct rtable *rt) { <------>return rt && <------><------>rt->dst.obsolete == DST_OBSOLETE_FORCE_CHK && <------><------>!rt_is_expired(rt); } static void rt_set_nexthop(struct rtable *rt, __be32 daddr, <------><------><------> const struct fib_result *res, <------><------><------> struct fib_nh_exception *fnhe, <------><------><------> struct fib_info *fi, u16 type, u32 itag, <------><------><------> const bool do_cache) { <------>bool cached = false; <------>if (fi) { <------><------>struct fib_nh_common *nhc = FIB_RES_NHC(*res); <------><------>if (nhc->nhc_gw_family && nhc->nhc_scope == RT_SCOPE_LINK) { <------><------><------>rt->rt_uses_gateway = 1; <------><------><------>rt->rt_gw_family = nhc->nhc_gw_family; <------><------><------>/* only INET and INET6 are supported */ <------><------><------>if (likely(nhc->nhc_gw_family == AF_INET)) <------><------><------><------>rt->rt_gw4 = nhc->nhc_gw.ipv4; <------><------><------>else <------><------><------><------>rt->rt_gw6 = nhc->nhc_gw.ipv6; <------><------>} <------><------>ip_dst_init_metrics(&rt->dst, fi->fib_metrics); #ifdef CONFIG_IP_ROUTE_CLASSID <------><------>if (nhc->nhc_family == AF_INET) { <------><------><------>struct fib_nh *nh; <------><------><------>nh = container_of(nhc, struct fib_nh, nh_common); <------><------><------>rt->dst.tclassid = nh->nh_tclassid; <------><------>} #endif <------><------>rt->dst.lwtstate = lwtstate_get(nhc->nhc_lwtstate); <------><------>if (unlikely(fnhe)) <------><------><------>cached = rt_bind_exception(rt, fnhe, daddr, do_cache); <------><------>else if (do_cache) <------><------><------>cached = rt_cache_route(nhc, rt); <------><------>if (unlikely(!cached)) { <------><------><------>/* Routes we intend to cache in nexthop exception or <------><------><------> * FIB nexthop have the DST_NOCACHE bit clear. <------><------><------> * However, if we are unsuccessful at storing this <------><------><------> * route into the cache we really need to set it. <------><------><------> */ <------><------><------>if (!rt->rt_gw4) { <------><------><------><------>rt->rt_gw_family = AF_INET; <------><------><------><------>rt->rt_gw4 = daddr; <------><------><------>} <------><------><------>rt_add_uncached_list(rt); <------><------>} <------>} else <------><------>rt_add_uncached_list(rt); #ifdef CONFIG_IP_ROUTE_CLASSID #ifdef CONFIG_IP_MULTIPLE_TABLES <------>set_class_tag(rt, res->tclassid); #endif <------>set_class_tag(rt, itag); #endif } struct rtable *rt_dst_alloc(struct net_device *dev, <------><------><------> unsigned int flags, u16 type, <------><------><------> bool nopolicy, bool noxfrm) { <------>struct rtable *rt; <------>rt = dst_alloc(&ipv4_dst_ops, dev, 1, DST_OBSOLETE_FORCE_CHK, <------><------> (nopolicy ? DST_NOPOLICY : 0) | <------><------> (noxfrm ? DST_NOXFRM : 0)); <------>if (rt) { <------><------>rt->rt_genid = rt_genid_ipv4(dev_net(dev)); <------><------>rt->rt_flags = flags; <------><------>rt->rt_type = type; <------><------>rt->rt_is_input = 0; <------><------>rt->rt_iif = 0; <------><------>rt->rt_pmtu = 0; <------><------>rt->rt_mtu_locked = 0; <------><------>rt->rt_uses_gateway = 0; <------><------>rt->rt_gw_family = 0; <------><------>rt->rt_gw4 = 0; <------><------>INIT_LIST_HEAD(&rt->rt_uncached); <------><------>rt->dst.output = ip_output; <------><------>if (flags & RTCF_LOCAL) <------><------><------>rt->dst.input = ip_local_deliver; <------>} <------>return rt; } EXPORT_SYMBOL(rt_dst_alloc); struct rtable *rt_dst_clone(struct net_device *dev, struct rtable *rt) { <------>struct rtable *new_rt; <------>new_rt = dst_alloc(&ipv4_dst_ops, dev, 1, DST_OBSOLETE_FORCE_CHK, <------><------><------> rt->dst.flags); <------>if (new_rt) { <------><------>new_rt->rt_genid = rt_genid_ipv4(dev_net(dev)); <------><------>new_rt->rt_flags = rt->rt_flags; <------><------>new_rt->rt_type = rt->rt_type; <------><------>new_rt->rt_is_input = rt->rt_is_input; <------><------>new_rt->rt_iif = rt->rt_iif; <------><------>new_rt->rt_pmtu = rt->rt_pmtu; <------><------>new_rt->rt_mtu_locked = rt->rt_mtu_locked; <------><------>new_rt->rt_gw_family = rt->rt_gw_family; <------><------>if (rt->rt_gw_family == AF_INET) <------><------><------>new_rt->rt_gw4 = rt->rt_gw4; <------><------>else if (rt->rt_gw_family == AF_INET6) <------><------><------>new_rt->rt_gw6 = rt->rt_gw6; <------><------>INIT_LIST_HEAD(&new_rt->rt_uncached); <------><------>new_rt->dst.input = rt->dst.input; <------><------>new_rt->dst.output = rt->dst.output; <------><------>new_rt->dst.error = rt->dst.error; <------><------>new_rt->dst.lastuse = jiffies; <------><------>new_rt->dst.lwtstate = lwtstate_get(rt->dst.lwtstate); <------>} <------>return new_rt; } EXPORT_SYMBOL(rt_dst_clone); /* called in rcu_read_lock() section */ int ip_mc_validate_source(struct sk_buff *skb, __be32 daddr, __be32 saddr, <------><------><------> u8 tos, struct net_device *dev, <------><------><------> struct in_device *in_dev, u32 *itag) { <------>int err; <------>/* Primary sanity checks. */ <------>if (!in_dev) <------><------>return -EINVAL; <------>if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr) || <------> skb->protocol != htons(ETH_P_IP)) <------><------>return -EINVAL; <------>if (ipv4_is_loopback(saddr) && !IN_DEV_ROUTE_LOCALNET(in_dev)) <------><------>return -EINVAL; <------>if (ipv4_is_zeronet(saddr)) { <------><------>if (!ipv4_is_local_multicast(daddr) && <------><------> ip_hdr(skb)->protocol != IPPROTO_IGMP) <------><------><------>return -EINVAL; <------>} else { <------><------>err = fib_validate_source(skb, saddr, 0, tos, 0, dev, <------><------><------><------><------> in_dev, itag); <------><------>if (err < 0) <------><------><------>return err; <------>} <------>return 0; } /* called in rcu_read_lock() section */ static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr, <------><------><------> u8 tos, struct net_device *dev, int our) { <------>struct in_device *in_dev = __in_dev_get_rcu(dev); <------>unsigned int flags = RTCF_MULTICAST; <------>struct rtable *rth; <------>u32 itag = 0; <------>int err; <------>err = ip_mc_validate_source(skb, daddr, saddr, tos, dev, in_dev, &itag); <------>if (err) <------><------>return err; <------>if (our) <------><------>flags |= RTCF_LOCAL; <------>rth = rt_dst_alloc(dev_net(dev)->loopback_dev, flags, RTN_MULTICAST, <------><------><------> IN_DEV_CONF_GET(in_dev, NOPOLICY), false); <------>if (!rth) <------><------>return -ENOBUFS; #ifdef CONFIG_IP_ROUTE_CLASSID <------>rth->dst.tclassid = itag; #endif <------>rth->dst.output = ip_rt_bug; <------>rth->rt_is_input= 1; #ifdef CONFIG_IP_MROUTE <------>if (!ipv4_is_local_multicast(daddr) && IN_DEV_MFORWARD(in_dev)) <------><------>rth->dst.input = ip_mr_input; #endif <------>RT_CACHE_STAT_INC(in_slow_mc); <------>skb_dst_set(skb, &rth->dst); <------>return 0; } static void ip_handle_martian_source(struct net_device *dev, <------><------><------><------> struct in_device *in_dev, <------><------><------><------> struct sk_buff *skb, <------><------><------><------> __be32 daddr, <------><------><------><------> __be32 saddr) { <------>RT_CACHE_STAT_INC(in_martian_src); #ifdef CONFIG_IP_ROUTE_VERBOSE <------>if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit()) { <------><------>/* <------><------> * RFC1812 recommendation, if source is martian, <------><------> * the only hint is MAC header. <------><------> */ <------><------>pr_warn("martian source %pI4 from %pI4, on dev %s\n", <------><------><------>&daddr, &saddr, dev->name); <------><------>if (dev->hard_header_len && skb_mac_header_was_set(skb)) { <------><------><------>print_hex_dump(KERN_WARNING, "ll header: ", <------><------><------><------> DUMP_PREFIX_OFFSET, 16, 1, <------><------><------><------> skb_mac_header(skb), <------><------><------><------> dev->hard_header_len, false); <------><------>} <------>} #endif } /* called in rcu_read_lock() section */ static int __mkroute_input(struct sk_buff *skb, <------><------><------> const struct fib_result *res, <------><------><------> struct in_device *in_dev, <------><------><------> __be32 daddr, __be32 saddr, u32 tos) { <------>struct fib_nh_common *nhc = FIB_RES_NHC(*res); <------>struct net_device *dev = nhc->nhc_dev; <------>struct fib_nh_exception *fnhe; <------>struct rtable *rth; <------>int err; <------>struct in_device *out_dev; <------>bool do_cache; <------>u32 itag = 0; <------>/* get a working reference to the output device */ <------>out_dev = __in_dev_get_rcu(dev); <------>if (!out_dev) { <------><------>net_crit_ratelimited("Bug in ip_route_input_slow(). Please report.\n"); <------><------>return -EINVAL; <------>} <------>err = fib_validate_source(skb, saddr, daddr, tos, FIB_RES_OIF(*res), <------><------><------><------> in_dev->dev, in_dev, &itag); <------>if (err < 0) { <------><------>ip_handle_martian_source(in_dev->dev, in_dev, skb, daddr, <------><------><------><------><------> saddr); <------><------>goto cleanup; <------>} <------>do_cache = res->fi && !itag; <------>if (out_dev == in_dev && err && IN_DEV_TX_REDIRECTS(out_dev) && <------> skb->protocol == htons(ETH_P_IP)) { <------><------>__be32 gw; <------><------>gw = nhc->nhc_gw_family == AF_INET ? nhc->nhc_gw.ipv4 : 0; <------><------>if (IN_DEV_SHARED_MEDIA(out_dev) || <------><------> inet_addr_onlink(out_dev, saddr, gw)) <------><------><------>IPCB(skb)->flags |= IPSKB_DOREDIRECT; <------>} <------>if (skb->protocol != htons(ETH_P_IP)) { <------><------>/* Not IP (i.e. ARP). Do not create route, if it is <------><------> * invalid for proxy arp. DNAT routes are always valid. <------><------> * <------><------> * Proxy arp feature have been extended to allow, ARP <------><------> * replies back to the same interface, to support <------><------> * Private VLAN switch technologies. See arp.c. <------><------> */ <------><------>if (out_dev == in_dev && <------><------> IN_DEV_PROXY_ARP_PVLAN(in_dev) == 0) { <------><------><------>err = -EINVAL; <------><------><------>goto cleanup; <------><------>} <------>} <------>fnhe = find_exception(nhc, daddr); <------>if (do_cache) { <------><------>if (fnhe) <------><------><------>rth = rcu_dereference(fnhe->fnhe_rth_input); <------><------>else <------><------><------>rth = rcu_dereference(nhc->nhc_rth_input); <------><------>if (rt_cache_valid(rth)) { <------><------><------>skb_dst_set_noref(skb, &rth->dst); <------><------><------>goto out; <------><------>} <------>} <------>rth = rt_dst_alloc(out_dev->dev, 0, res->type, <------><------><------> IN_DEV_CONF_GET(in_dev, NOPOLICY), <------><------><------> IN_DEV_CONF_GET(out_dev, NOXFRM)); <------>if (!rth) { <------><------>err = -ENOBUFS; <------><------>goto cleanup; <------>} <------>rth->rt_is_input = 1; <------>RT_CACHE_STAT_INC(in_slow_tot); <------>rth->dst.input = ip_forward; <------>rt_set_nexthop(rth, daddr, res, fnhe, res->fi, res->type, itag, <------><------> do_cache); <------>lwtunnel_set_redirect(&rth->dst); <------>skb_dst_set(skb, &rth->dst); out: <------>err = 0; cleanup: <------>return err; } #ifdef CONFIG_IP_ROUTE_MULTIPATH /* To make ICMP packets follow the right flow, the multipath hash is * calculated from the inner IP addresses. */ static void ip_multipath_l3_keys(const struct sk_buff *skb, <------><------><------><------> struct flow_keys *hash_keys) { <------>const struct iphdr *outer_iph = ip_hdr(skb); <------>const struct iphdr *key_iph = outer_iph; <------>const struct iphdr *inner_iph; <------>const struct icmphdr *icmph; <------>struct iphdr _inner_iph; <------>struct icmphdr _icmph; <------>if (likely(outer_iph->protocol != IPPROTO_ICMP)) <------><------>goto out; <------>if (unlikely((outer_iph->frag_off & htons(IP_OFFSET)) != 0)) <------><------>goto out; <------>icmph = skb_header_pointer(skb, outer_iph->ihl * 4, sizeof(_icmph), <------><------><------><------> &_icmph); <------>if (!icmph) <------><------>goto out; <------>if (!icmp_is_err(icmph->type)) <------><------>goto out; <------>inner_iph = skb_header_pointer(skb, <------><------><------><------> outer_iph->ihl * 4 + sizeof(_icmph), <------><------><------><------> sizeof(_inner_iph), &_inner_iph); <------>if (!inner_iph) <------><------>goto out; <------>key_iph = inner_iph; out: <------>hash_keys->addrs.v4addrs.src = key_iph->saddr; <------>hash_keys->addrs.v4addrs.dst = key_iph->daddr; } /* if skb is set it will be used and fl4 can be NULL */ int fib_multipath_hash(const struct net *net, const struct flowi4 *fl4, <------><------> const struct sk_buff *skb, struct flow_keys *flkeys) { <------>u32 multipath_hash = fl4 ? fl4->flowi4_multipath_hash : 0; <------>struct flow_keys hash_keys; <------>u32 mhash; <------>switch (net->ipv4.sysctl_fib_multipath_hash_policy) { <------>case 0: <------><------>memset(&hash_keys, 0, sizeof(hash_keys)); <------><------>hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS; <------><------>if (skb) { <------><------><------>ip_multipath_l3_keys(skb, &hash_keys); <------><------>} else { <------><------><------>hash_keys.addrs.v4addrs.src = fl4->saddr; <------><------><------>hash_keys.addrs.v4addrs.dst = fl4->daddr; <------><------>} <------><------>break; <------>case 1: <------><------>/* skb is currently provided only when forwarding */ <------><------>if (skb) { <------><------><------>unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP; <------><------><------>struct flow_keys keys; <------><------><------>/* short-circuit if we already have L4 hash present */ <------><------><------>if (skb->l4_hash) <------><------><------><------>return skb_get_hash_raw(skb) >> 1; <------><------><------>memset(&hash_keys, 0, sizeof(hash_keys)); <------><------><------>if (!flkeys) { <------><------><------><------>skb_flow_dissect_flow_keys(skb, &keys, flag); <------><------><------><------>flkeys = &keys; <------><------><------>} <------><------><------>hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS; <------><------><------>hash_keys.addrs.v4addrs.src = flkeys->addrs.v4addrs.src; <------><------><------>hash_keys.addrs.v4addrs.dst = flkeys->addrs.v4addrs.dst; <------><------><------>hash_keys.ports.src = flkeys->ports.src; <------><------><------>hash_keys.ports.dst = flkeys->ports.dst; <------><------><------>hash_keys.basic.ip_proto = flkeys->basic.ip_proto; <------><------>} else { <------><------><------>memset(&hash_keys, 0, sizeof(hash_keys)); <------><------><------>hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS; <------><------><------>hash_keys.addrs.v4addrs.src = fl4->saddr; <------><------><------>hash_keys.addrs.v4addrs.dst = fl4->daddr; <------><------><------>hash_keys.ports.src = fl4->fl4_sport; <------><------><------>hash_keys.ports.dst = fl4->fl4_dport; <------><------><------>hash_keys.basic.ip_proto = fl4->flowi4_proto; <------><------>} <------><------>break; <------>case 2: <------><------>memset(&hash_keys, 0, sizeof(hash_keys)); <------><------>/* skb is currently provided only when forwarding */ <------><------>if (skb) { <------><------><------>struct flow_keys keys; <------><------><------>skb_flow_dissect_flow_keys(skb, &keys, 0); <------><------><------>/* Inner can be v4 or v6 */ <------><------><------>if (keys.control.addr_type == FLOW_DISSECTOR_KEY_IPV4_ADDRS) { <------><------><------><------>hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS; <------><------><------><------>hash_keys.addrs.v4addrs.src = keys.addrs.v4addrs.src; <------><------><------><------>hash_keys.addrs.v4addrs.dst = keys.addrs.v4addrs.dst; <------><------><------>} else if (keys.control.addr_type == FLOW_DISSECTOR_KEY_IPV6_ADDRS) { <------><------><------><------>hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS; <------><------><------><------>hash_keys.addrs.v6addrs.src = keys.addrs.v6addrs.src; <------><------><------><------>hash_keys.addrs.v6addrs.dst = keys.addrs.v6addrs.dst; <------><------><------><------>hash_keys.tags.flow_label = keys.tags.flow_label; <------><------><------><------>hash_keys.basic.ip_proto = keys.basic.ip_proto; <------><------><------>} else { <------><------><------><------>/* Same as case 0 */ <------><------><------><------>hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS; <------><------><------><------>ip_multipath_l3_keys(skb, &hash_keys); <------><------><------>} <------><------>} else { <------><------><------>/* Same as case 0 */ <------><------><------>hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS; <------><------><------>hash_keys.addrs.v4addrs.src = fl4->saddr; <------><------><------>hash_keys.addrs.v4addrs.dst = fl4->daddr; <------><------>} <------><------>break; <------>} <------>mhash = flow_hash_from_keys(&hash_keys); <------>if (multipath_hash) <------><------>mhash = jhash_2words(mhash, multipath_hash, 0); <------>return mhash >> 1; } #endif /* CONFIG_IP_ROUTE_MULTIPATH */ static int ip_mkroute_input(struct sk_buff *skb, <------><------><------> struct fib_result *res, <------><------><------> struct in_device *in_dev, <------><------><------> __be32 daddr, __be32 saddr, u32 tos, <------><------><------> struct flow_keys *hkeys) { #ifdef CONFIG_IP_ROUTE_MULTIPATH <------>if (res->fi && fib_info_num_path(res->fi) > 1) { <------><------>int h = fib_multipath_hash(res->fi->fib_net, NULL, skb, hkeys); <------><------>fib_select_multipath(res, h); <------>} #endif <------>/* create a routing cache entry */ <------>return __mkroute_input(skb, res, in_dev, daddr, saddr, tos); } /* Implements all the saddr-related checks as ip_route_input_slow(), * assuming daddr is valid and the destination is not a local broadcast one. * Uses the provided hint instead of performing a route lookup. */ int ip_route_use_hint(struct sk_buff *skb, __be32 daddr, __be32 saddr, <------><------> u8 tos, struct net_device *dev, <------><------> const struct sk_buff *hint) { <------>struct in_device *in_dev = __in_dev_get_rcu(dev); <------>struct rtable *rt = skb_rtable(hint); <------>struct net *net = dev_net(dev); <------>int err = -EINVAL; <------>u32 tag = 0; <------>if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr)) <------><------>goto martian_source; <------>if (ipv4_is_zeronet(saddr)) <------><------>goto martian_source; <------>if (ipv4_is_loopback(saddr) && !IN_DEV_NET_ROUTE_LOCALNET(in_dev, net)) <------><------>goto martian_source; <------>if (rt->rt_type != RTN_LOCAL) <------><------>goto skip_validate_source; <------>tos &= IPTOS_RT_MASK; <------>err = fib_validate_source(skb, saddr, daddr, tos, 0, dev, in_dev, &tag); <------>if (err < 0) <------><------>goto martian_source; skip_validate_source: <------>skb_dst_copy(skb, hint); <------>return 0; martian_source: <------>ip_handle_martian_source(dev, in_dev, skb, daddr, saddr); <------>return err; } /* get device for dst_alloc with local routes */ static struct net_device *ip_rt_get_dev(struct net *net, <------><------><------><------><------>const struct fib_result *res) { <------>struct fib_nh_common *nhc = res->fi ? res->nhc : NULL; <------>struct net_device *dev = NULL; <------>if (nhc) <------><------>dev = l3mdev_master_dev_rcu(nhc->nhc_dev); <------>return dev ? : net->loopback_dev; } /* * NOTE. We drop all the packets that has local source * addresses, because every properly looped back packet * must have correct destination already attached by output routine. * Changes in the enforced policies must be applied also to * ip_route_use_hint(). * * Such approach solves two big problems: * 1. Not simplex devices are handled properly. * 2. IP spoofing attempts are filtered with 100% of guarantee. * called with rcu_read_lock() */ static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr, <------><------><------> u8 tos, struct net_device *dev, <------><------><------> struct fib_result *res) { <------>struct in_device *in_dev = __in_dev_get_rcu(dev); <------>struct flow_keys *flkeys = NULL, _flkeys; <------>struct net *net = dev_net(dev); <------>struct ip_tunnel_info *tun_info; <------>int err = -EINVAL; <------>unsigned int flags = 0; <------>u32 itag = 0; <------>struct rtable *rth; <------>struct flowi4 fl4; <------>bool do_cache = true; <------>/* IP on this device is disabled. */ <------>if (!in_dev) <------><------>goto out; <------>/* Check for the most weird martians, which can be not detected <------> by fib_lookup. <------> */ <------>tun_info = skb_tunnel_info(skb); <------>if (tun_info && !(tun_info->mode & IP_TUNNEL_INFO_TX)) <------><------>fl4.flowi4_tun_key.tun_id = tun_info->key.tun_id; <------>else <------><------>fl4.flowi4_tun_key.tun_id = 0; <------>skb_dst_drop(skb); <------>if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr)) <------><------>goto martian_source; <------>res->fi = NULL; <------>res->table = NULL; <------>if (ipv4_is_lbcast(daddr) || (saddr == 0 && daddr == 0)) <------><------>goto brd_input; <------>/* Accept zero addresses only to limited broadcast; <------> * I even do not know to fix it or not. Waiting for complains :-) <------> */ <------>if (ipv4_is_zeronet(saddr)) <------><------>goto martian_source; <------>if (ipv4_is_zeronet(daddr)) <------><------>goto martian_destination; <------>/* Following code try to avoid calling IN_DEV_NET_ROUTE_LOCALNET(), <------> * and call it once if daddr or/and saddr are loopback addresses <------> */ <------>if (ipv4_is_loopback(daddr)) { <------><------>if (!IN_DEV_NET_ROUTE_LOCALNET(in_dev, net)) <------><------><------>goto martian_destination; <------>} else if (ipv4_is_loopback(saddr)) { <------><------>if (!IN_DEV_NET_ROUTE_LOCALNET(in_dev, net)) <------><------><------>goto martian_source; <------>} <------>/* <------> * Now we are ready to route packet. <------> */ <------>fl4.flowi4_oif = 0; <------>fl4.flowi4_iif = dev->ifindex; <------>fl4.flowi4_mark = skb->mark; <------>fl4.flowi4_tos = tos; <------>fl4.flowi4_scope = RT_SCOPE_UNIVERSE; <------>fl4.flowi4_flags = 0; <------>fl4.daddr = daddr; <------>fl4.saddr = saddr; <------>fl4.flowi4_uid = sock_net_uid(net, NULL); <------>fl4.flowi4_multipath_hash = 0; <------>if (fib4_rules_early_flow_dissect(net, skb, &fl4, &_flkeys)) { <------><------>flkeys = &_flkeys; <------>} else { <------><------>fl4.flowi4_proto = 0; <------><------>fl4.fl4_sport = 0; <------><------>fl4.fl4_dport = 0; <------>} <------>err = fib_lookup(net, &fl4, res, 0); <------>if (err != 0) { <------><------>if (!IN_DEV_FORWARD(in_dev)) <------><------><------>err = -EHOSTUNREACH; <------><------>goto no_route; <------>} <------>if (res->type == RTN_BROADCAST) { <------><------>if (IN_DEV_BFORWARD(in_dev)) <------><------><------>goto make_route; <------><------>/* not do cache if bc_forwarding is enabled */ <------><------>if (IPV4_DEVCONF_ALL(net, BC_FORWARDING)) <------><------><------>do_cache = false; <------><------>goto brd_input; <------>} <------>if (res->type == RTN_LOCAL) { <------><------>err = fib_validate_source(skb, saddr, daddr, tos, <------><------><------><------><------> 0, dev, in_dev, &itag); <------><------>if (err < 0) <------><------><------>goto martian_source; <------><------>goto local_input; <------>} <------>if (!IN_DEV_FORWARD(in_dev)) { <------><------>err = -EHOSTUNREACH; <------><------>goto no_route; <------>} <------>if (res->type != RTN_UNICAST) <------><------>goto martian_destination; make_route: <------>err = ip_mkroute_input(skb, res, in_dev, daddr, saddr, tos, flkeys); out: return err; brd_input: <------>if (skb->protocol != htons(ETH_P_IP)) <------><------>goto e_inval; <------>if (!ipv4_is_zeronet(saddr)) { <------><------>err = fib_validate_source(skb, saddr, 0, tos, 0, dev, <------><------><------><------><------> in_dev, &itag); <------><------>if (err < 0) <------><------><------>goto martian_source; <------>} <------>flags |= RTCF_BROADCAST; <------>res->type = RTN_BROADCAST; <------>RT_CACHE_STAT_INC(in_brd); local_input: <------>do_cache &= res->fi && !itag; <------>if (do_cache) { <------><------>struct fib_nh_common *nhc = FIB_RES_NHC(*res); <------><------>rth = rcu_dereference(nhc->nhc_rth_input); <------><------>if (rt_cache_valid(rth)) { <------><------><------>skb_dst_set_noref(skb, &rth->dst); <------><------><------>err = 0; <------><------><------>goto out; <------><------>} <------>} <------>rth = rt_dst_alloc(ip_rt_get_dev(net, res), <------><------><------> flags | RTCF_LOCAL, res->type, <------><------><------> IN_DEV_CONF_GET(in_dev, NOPOLICY), false); <------>if (!rth) <------><------>goto e_nobufs; <------>rth->dst.output= ip_rt_bug; #ifdef CONFIG_IP_ROUTE_CLASSID <------>rth->dst.tclassid = itag; #endif <------>rth->rt_is_input = 1; <------>RT_CACHE_STAT_INC(in_slow_tot); <------>if (res->type == RTN_UNREACHABLE) { <------><------>rth->dst.input= ip_error; <------><------>rth->dst.error= -err; <------><------>rth->rt_flags &= ~RTCF_LOCAL; <------>} <------>if (do_cache) { <------><------>struct fib_nh_common *nhc = FIB_RES_NHC(*res); <------><------>rth->dst.lwtstate = lwtstate_get(nhc->nhc_lwtstate); <------><------>if (lwtunnel_input_redirect(rth->dst.lwtstate)) { <------><------><------>WARN_ON(rth->dst.input == lwtunnel_input); <------><------><------>rth->dst.lwtstate->orig_input = rth->dst.input; <------><------><------>rth->dst.input = lwtunnel_input; <------><------>} <------><------>if (unlikely(!rt_cache_route(nhc, rth))) <------><------><------>rt_add_uncached_list(rth); <------>} <------>skb_dst_set(skb, &rth->dst); <------>err = 0; <------>goto out; no_route: <------>RT_CACHE_STAT_INC(in_no_route); <------>res->type = RTN_UNREACHABLE; <------>res->fi = NULL; <------>res->table = NULL; <------>goto local_input; <------>/* <------> * Do not cache martian addresses: they should be logged (RFC1812) <------> */ martian_destination: <------>RT_CACHE_STAT_INC(in_martian_dst); #ifdef CONFIG_IP_ROUTE_VERBOSE <------>if (IN_DEV_LOG_MARTIANS(in_dev)) <------><------>net_warn_ratelimited("martian destination %pI4 from %pI4, dev %s\n", <------><------><------><------> &daddr, &saddr, dev->name); #endif e_inval: <------>err = -EINVAL; <------>goto out; e_nobufs: <------>err = -ENOBUFS; <------>goto out; martian_source: <------>ip_handle_martian_source(dev, in_dev, skb, daddr, saddr); <------>goto out; } int ip_route_input_noref(struct sk_buff *skb, __be32 daddr, __be32 saddr, <------><------><------> u8 tos, struct net_device *dev) { <------>struct fib_result res; <------>int err; <------>tos &= IPTOS_RT_MASK; <------>rcu_read_lock(); <------>err = ip_route_input_rcu(skb, daddr, saddr, tos, dev, &res); <------>rcu_read_unlock(); <------>return err; } EXPORT_SYMBOL(ip_route_input_noref); /* called with rcu_read_lock held */ int ip_route_input_rcu(struct sk_buff *skb, __be32 daddr, __be32 saddr, <------><------> u8 tos, struct net_device *dev, struct fib_result *res) { <------>/* Multicast recognition logic is moved from route cache to here. <------> The problem was that too many Ethernet cards have broken/missing <------> hardware multicast filters :-( As result the host on multicasting <------> network acquires a lot of useless route cache entries, sort of <------> SDR messages from all the world. Now we try to get rid of them. <------> Really, provided software IP multicast filter is organized <------> reasonably (at least, hashed), it does not result in a slowdown <------> comparing with route cache reject entries. <------> Note, that multicast routers are not affected, because <------> route cache entry is created eventually. <------> */ <------>if (ipv4_is_multicast(daddr)) { <------><------>struct in_device *in_dev = __in_dev_get_rcu(dev); <------><------>int our = 0; <------><------>int err = -EINVAL; <------><------>if (!in_dev) <------><------><------>return err; <------><------>our = ip_check_mc_rcu(in_dev, daddr, saddr, <------><------><------><------> ip_hdr(skb)->protocol); <------><------>/* check l3 master if no match yet */ <------><------>if (!our && netif_is_l3_slave(dev)) { <------><------><------>struct in_device *l3_in_dev; <------><------><------>l3_in_dev = __in_dev_get_rcu(skb->dev); <------><------><------>if (l3_in_dev) <------><------><------><------>our = ip_check_mc_rcu(l3_in_dev, daddr, saddr, <------><------><------><------><------><------> ip_hdr(skb)->protocol); <------><------>} <------><------>if (our #ifdef CONFIG_IP_MROUTE <------><------><------>|| <------><------> (!ipv4_is_local_multicast(daddr) && <------><------> IN_DEV_MFORWARD(in_dev)) #endif <------><------> ) { <------><------><------>err = ip_route_input_mc(skb, daddr, saddr, <------><------><------><------><------><------>tos, dev, our); <------><------>} <------><------>return err; <------>} <------>return ip_route_input_slow(skb, daddr, saddr, tos, dev, res); } /* called with rcu_read_lock() */ static struct rtable *__mkroute_output(const struct fib_result *res, <------><------><------><------> const struct flowi4 *fl4, int orig_oif, <------><------><------><------> struct net_device *dev_out, <------><------><------><------> unsigned int flags) { <------>struct fib_info *fi = res->fi; <------>struct fib_nh_exception *fnhe; <------>struct in_device *in_dev; <------>u16 type = res->type; <------>struct rtable *rth; <------>bool do_cache; <------>in_dev = __in_dev_get_rcu(dev_out); <------>if (!in_dev) <------><------>return ERR_PTR(-EINVAL); <------>if (likely(!IN_DEV_ROUTE_LOCALNET(in_dev))) <------><------>if (ipv4_is_loopback(fl4->saddr) && <------><------> !(dev_out->flags & IFF_LOOPBACK) && <------><------> !netif_is_l3_master(dev_out)) <------><------><------>return ERR_PTR(-EINVAL); <------>if (ipv4_is_lbcast(fl4->daddr)) <------><------>type = RTN_BROADCAST; <------>else if (ipv4_is_multicast(fl4->daddr)) <------><------>type = RTN_MULTICAST; <------>else if (ipv4_is_zeronet(fl4->daddr)) <------><------>return ERR_PTR(-EINVAL); <------>if (dev_out->flags & IFF_LOOPBACK) <------><------>flags |= RTCF_LOCAL; <------>do_cache = true; <------>if (type == RTN_BROADCAST) { <------><------>flags |= RTCF_BROADCAST | RTCF_LOCAL; <------><------>fi = NULL; <------>} else if (type == RTN_MULTICAST) { <------><------>flags |= RTCF_MULTICAST | RTCF_LOCAL; <------><------>if (!ip_check_mc_rcu(in_dev, fl4->daddr, fl4->saddr, <------><------><------><------> fl4->flowi4_proto)) <------><------><------>flags &= ~RTCF_LOCAL; <------><------>else <------><------><------>do_cache = false; <------><------>/* If multicast route do not exist use <------><------> * default one, but do not gateway in this case. <------><------> * Yes, it is hack. <------><------> */ <------><------>if (fi && res->prefixlen < 4) <------><------><------>fi = NULL; <------>} else if ((type == RTN_LOCAL) && (orig_oif != 0) && <------><------> (orig_oif != dev_out->ifindex)) { <------><------>/* For local routes that require a particular output interface <------><------> * we do not want to cache the result. Caching the result <------><------> * causes incorrect behaviour when there are multiple source <------><------> * addresses on the interface, the end result being that if the <------><------> * intended recipient is waiting on that interface for the <------><------> * packet he won't receive it because it will be delivered on <------><------> * the loopback interface and the IP_PKTINFO ipi_ifindex will <------><------> * be set to the loopback interface as well. <------><------> */ <------><------>do_cache = false; <------>} <------>fnhe = NULL; <------>do_cache &= fi != NULL; <------>if (fi) { <------><------>struct fib_nh_common *nhc = FIB_RES_NHC(*res); <------><------>struct rtable __rcu **prth; <------><------>fnhe = find_exception(nhc, fl4->daddr); <------><------>if (!do_cache) <------><------><------>goto add; <------><------>if (fnhe) { <------><------><------>prth = &fnhe->fnhe_rth_output; <------><------>} else { <------><------><------>if (unlikely(fl4->flowi4_flags & <------><------><------><------> FLOWI_FLAG_KNOWN_NH && <------><------><------><------> !(nhc->nhc_gw_family && <------><------><------><------> nhc->nhc_scope == RT_SCOPE_LINK))) { <------><------><------><------>do_cache = false; <------><------><------><------>goto add; <------><------><------>} <------><------><------>prth = raw_cpu_ptr(nhc->nhc_pcpu_rth_output); <------><------>} <------><------>rth = rcu_dereference(*prth); <------><------>if (rt_cache_valid(rth) && dst_hold_safe(&rth->dst)) <------><------><------>return rth; <------>} add: <------>rth = rt_dst_alloc(dev_out, flags, type, <------><------><------> IN_DEV_CONF_GET(in_dev, NOPOLICY), <------><------><------> IN_DEV_CONF_GET(in_dev, NOXFRM)); <------>if (!rth) <------><------>return ERR_PTR(-ENOBUFS); <------>rth->rt_iif = orig_oif; <------>RT_CACHE_STAT_INC(out_slow_tot); <------>if (flags & (RTCF_BROADCAST | RTCF_MULTICAST)) { <------><------>if (flags & RTCF_LOCAL && <------><------> !(dev_out->flags & IFF_LOOPBACK)) { <------><------><------>rth->dst.output = ip_mc_output; <------><------><------>RT_CACHE_STAT_INC(out_slow_mc); <------><------>} #ifdef CONFIG_IP_MROUTE <------><------>if (type == RTN_MULTICAST) { <------><------><------>if (IN_DEV_MFORWARD(in_dev) && <------><------><------> !ipv4_is_local_multicast(fl4->daddr)) { <------><------><------><------>rth->dst.input = ip_mr_input; <------><------><------><------>rth->dst.output = ip_mc_output; <------><------><------>} <------><------>} #endif <------>} <------>rt_set_nexthop(rth, fl4->daddr, res, fnhe, fi, type, 0, do_cache); <------>lwtunnel_set_redirect(&rth->dst); <------>return rth; } /* * Major route resolver routine. */ struct rtable *ip_route_output_key_hash(struct net *net, struct flowi4 *fl4, <------><------><------><------><------>const struct sk_buff *skb) { <------>struct fib_result res = { <------><------>.type = RTN_UNSPEC, <------><------>.fi = NULL, <------><------>.table = NULL, <------><------>.tclassid = 0, <------>}; <------>struct rtable *rth; <------>fl4->flowi4_iif = LOOPBACK_IFINDEX; <------>ip_rt_fix_tos(fl4); <------>rcu_read_lock(); <------>rth = ip_route_output_key_hash_rcu(net, fl4, &res, skb); <------>rcu_read_unlock(); <------>return rth; } EXPORT_SYMBOL_GPL(ip_route_output_key_hash); struct rtable *ip_route_output_key_hash_rcu(struct net *net, struct flowi4 *fl4, <------><------><------><------><------> struct fib_result *res, <------><------><------><------><------> const struct sk_buff *skb) { <------>struct net_device *dev_out = NULL; <------>int orig_oif = fl4->flowi4_oif; <------>unsigned int flags = 0; <------>struct rtable *rth; <------>int err; <------>if (fl4->saddr) { <------><------>if (ipv4_is_multicast(fl4->saddr) || <------><------> ipv4_is_lbcast(fl4->saddr) || <------><------> ipv4_is_zeronet(fl4->saddr)) { <------><------><------>rth = ERR_PTR(-EINVAL); <------><------><------>goto out; <------><------>} <------><------>rth = ERR_PTR(-ENETUNREACH); <------><------>/* I removed check for oif == dev_out->oif here. <------><------> It was wrong for two reasons: <------><------> 1. ip_dev_find(net, saddr) can return wrong iface, if saddr <------><------> is assigned to multiple interfaces. <------><------> 2. Moreover, we are allowed to send packets with saddr <------><------> of another iface. --ANK <------><------> */ <------><------>if (fl4->flowi4_oif == 0 && <------><------> (ipv4_is_multicast(fl4->daddr) || <------><------> ipv4_is_lbcast(fl4->daddr))) { <------><------><------>/* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */ <------><------><------>dev_out = __ip_dev_find(net, fl4->saddr, false); <------><------><------>if (!dev_out) <------><------><------><------>goto out; <------><------><------>/* Special hack: user can direct multicasts <------><------><------> and limited broadcast via necessary interface <------><------><------> without fiddling with IP_MULTICAST_IF or IP_PKTINFO. <------><------><------> This hack is not just for fun, it allows <------><------><------> vic,vat and friends to work. <------><------><------> They bind socket to loopback, set ttl to zero <------><------><------> and expect that it will work. <------><------><------> From the viewpoint of routing cache they are broken, <------><------><------> because we are not allowed to build multicast path <------><------><------> with loopback source addr (look, routing cache <------><------><------> cannot know, that ttl is zero, so that packet <------><------><------> will not leave this host and route is valid). <------><------><------> Luckily, this hack is good workaround. <------><------><------> */ <------><------><------>fl4->flowi4_oif = dev_out->ifindex; <------><------><------>goto make_route; <------><------>} <------><------>if (!(fl4->flowi4_flags & FLOWI_FLAG_ANYSRC)) { <------><------><------>/* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */ <------><------><------>if (!__ip_dev_find(net, fl4->saddr, false)) <------><------><------><------>goto out; <------><------>} <------>} <------>if (fl4->flowi4_oif) { <------><------>dev_out = dev_get_by_index_rcu(net, fl4->flowi4_oif); <------><------>rth = ERR_PTR(-ENODEV); <------><------>if (!dev_out) <------><------><------>goto out; <------><------>/* RACE: Check return value of inet_select_addr instead. */ <------><------>if (!(dev_out->flags & IFF_UP) || !__in_dev_get_rcu(dev_out)) { <------><------><------>rth = ERR_PTR(-ENETUNREACH); <------><------><------>goto out; <------><------>} <------><------>if (ipv4_is_local_multicast(fl4->daddr) || <------><------> ipv4_is_lbcast(fl4->daddr) || <------><------> fl4->flowi4_proto == IPPROTO_IGMP) { <------><------><------>if (!fl4->saddr) <------><------><------><------>fl4->saddr = inet_select_addr(dev_out, 0, <------><------><------><------><------><------><------> RT_SCOPE_LINK); <------><------><------>goto make_route; <------><------>} <------><------>if (!fl4->saddr) { <------><------><------>if (ipv4_is_multicast(fl4->daddr)) <------><------><------><------>fl4->saddr = inet_select_addr(dev_out, 0, <------><------><------><------><------><------><------> fl4->flowi4_scope); <------><------><------>else if (!fl4->daddr) <------><------><------><------>fl4->saddr = inet_select_addr(dev_out, 0, <------><------><------><------><------><------><------> RT_SCOPE_HOST); <------><------>} <------>} <------>if (!fl4->daddr) { <------><------>fl4->daddr = fl4->saddr; <------><------>if (!fl4->daddr) <------><------><------>fl4->daddr = fl4->saddr = htonl(INADDR_LOOPBACK); <------><------>dev_out = net->loopback_dev; <------><------>fl4->flowi4_oif = LOOPBACK_IFINDEX; <------><------>res->type = RTN_LOCAL; <------><------>flags |= RTCF_LOCAL; <------><------>goto make_route; <------>} <------>err = fib_lookup(net, fl4, res, 0); <------>if (err) { <------><------>res->fi = NULL; <------><------>res->table = NULL; <------><------>if (fl4->flowi4_oif && <------><------> (ipv4_is_multicast(fl4->daddr) || <------><------> !netif_index_is_l3_master(net, fl4->flowi4_oif))) { <------><------><------>/* Apparently, routing tables are wrong. Assume, <------><------><------> that the destination is on link. <------><------><------> WHY? DW. <------><------><------> Because we are allowed to send to iface <------><------><------> even if it has NO routes and NO assigned <------><------><------> addresses. When oif is specified, routing <------><------><------> tables are looked up with only one purpose: <------><------><------> to catch if destination is gatewayed, rather than <------><------><------> direct. Moreover, if MSG_DONTROUTE is set, <------><------><------> we send packet, ignoring both routing tables <------><------><------> and ifaddr state. --ANK <------><------><------> We could make it even if oif is unknown, <------><------><------> likely IPv6, but we do not. <------><------><------> */ <------><------><------>if (fl4->saddr == 0) <------><------><------><------>fl4->saddr = inet_select_addr(dev_out, 0, <------><------><------><------><------><------><------> RT_SCOPE_LINK); <------><------><------>res->type = RTN_UNICAST; <------><------><------>goto make_route; <------><------>} <------><------>rth = ERR_PTR(err); <------><------>goto out; <------>} <------>if (res->type == RTN_LOCAL) { <------><------>if (!fl4->saddr) { <------><------><------>if (res->fi->fib_prefsrc) <------><------><------><------>fl4->saddr = res->fi->fib_prefsrc; <------><------><------>else <------><------><------><------>fl4->saddr = fl4->daddr; <------><------>} <------><------>/* L3 master device is the loopback for that domain */ <------><------>dev_out = l3mdev_master_dev_rcu(FIB_RES_DEV(*res)) ? : <------><------><------>net->loopback_dev; <------><------>/* make sure orig_oif points to fib result device even <------><------> * though packet rx/tx happens over loopback or l3mdev <------><------> */ <------><------>orig_oif = FIB_RES_OIF(*res); <------><------>fl4->flowi4_oif = dev_out->ifindex; <------><------>flags |= RTCF_LOCAL; <------><------>goto make_route; <------>} <------>fib_select_path(net, res, fl4, skb); <------>dev_out = FIB_RES_DEV(*res); make_route: <------>rth = __mkroute_output(res, fl4, orig_oif, dev_out, flags); out: <------>return rth; } static struct dst_ops ipv4_dst_blackhole_ops = { <------>.family = AF_INET, <------>.default_advmss = ipv4_default_advmss, <------>.neigh_lookup = ipv4_neigh_lookup, <------>.check = dst_blackhole_check, <------>.cow_metrics = dst_blackhole_cow_metrics, <------>.update_pmtu = dst_blackhole_update_pmtu, <------>.redirect = dst_blackhole_redirect, <------>.mtu = dst_blackhole_mtu, }; struct dst_entry *ipv4_blackhole_route(struct net *net, struct dst_entry *dst_orig) { <------>struct rtable *ort = (struct rtable *) dst_orig; <------>struct rtable *rt; <------>rt = dst_alloc(&ipv4_dst_blackhole_ops, NULL, 1, DST_OBSOLETE_DEAD, 0); <------>if (rt) { <------><------>struct dst_entry *new = &rt->dst; <------><------>new->__use = 1; <------><------>new->input = dst_discard; <------><------>new->output = dst_discard_out; <------><------>new->dev = net->loopback_dev; <------><------>if (new->dev) <------><------><------>dev_hold(new->dev); <------><------>rt->rt_is_input = ort->rt_is_input; <------><------>rt->rt_iif = ort->rt_iif; <------><------>rt->rt_pmtu = ort->rt_pmtu; <------><------>rt->rt_mtu_locked = ort->rt_mtu_locked; <------><------>rt->rt_genid = rt_genid_ipv4(net); <------><------>rt->rt_flags = ort->rt_flags; <------><------>rt->rt_type = ort->rt_type; <------><------>rt->rt_uses_gateway = ort->rt_uses_gateway; <------><------>rt->rt_gw_family = ort->rt_gw_family; <------><------>if (rt->rt_gw_family == AF_INET) <------><------><------>rt->rt_gw4 = ort->rt_gw4; <------><------>else if (rt->rt_gw_family == AF_INET6) <------><------><------>rt->rt_gw6 = ort->rt_gw6; <------><------>INIT_LIST_HEAD(&rt->rt_uncached); <------>} <------>dst_release(dst_orig); <------>return rt ? &rt->dst : ERR_PTR(-ENOMEM); } struct rtable *ip_route_output_flow(struct net *net, struct flowi4 *flp4, <------><------><------><------> const struct sock *sk) { <------>struct rtable *rt = __ip_route_output_key(net, flp4); <------>if (IS_ERR(rt)) <------><------>return rt; <------>if (flp4->flowi4_proto) { <------><------>flp4->flowi4_oif = rt->dst.dev->ifindex; <------><------>rt = (struct rtable *)xfrm_lookup_route(net, &rt->dst, <------><------><------><------><------><------><------>flowi4_to_flowi(flp4), <------><------><------><------><------><------><------>sk, 0); <------>} <------>return rt; } EXPORT_SYMBOL_GPL(ip_route_output_flow); struct rtable *ip_route_output_tunnel(struct sk_buff *skb, <------><------><------><------> struct net_device *dev, <------><------><------><------> struct net *net, __be32 *saddr, <------><------><------><------> const struct ip_tunnel_info *info, <------><------><------><------> u8 protocol, bool use_cache) { #ifdef CONFIG_DST_CACHE <------>struct dst_cache *dst_cache; #endif <------>struct rtable *rt = NULL; <------>struct flowi4 fl4; <------>__u8 tos; #ifdef CONFIG_DST_CACHE <------>dst_cache = (struct dst_cache *)&info->dst_cache; <------>if (use_cache) { <------><------>rt = dst_cache_get_ip4(dst_cache, saddr); <------><------>if (rt) <------><------><------>return rt; <------>} #endif <------>memset(&fl4, 0, sizeof(fl4)); <------>fl4.flowi4_mark = skb->mark; <------>fl4.flowi4_proto = protocol; <------>fl4.daddr = info->key.u.ipv4.dst; <------>fl4.saddr = info->key.u.ipv4.src; <------>tos = info->key.tos; <------>fl4.flowi4_tos = RT_TOS(tos); <------>rt = ip_route_output_key(net, &fl4); <------>if (IS_ERR(rt)) { <------><------>netdev_dbg(dev, "no route to %pI4\n", &fl4.daddr); <------><------>return ERR_PTR(-ENETUNREACH); <------>} <------>if (rt->dst.dev == dev) { /* is this necessary? */ <------><------>netdev_dbg(dev, "circular route to %pI4\n", &fl4.daddr); <------><------>ip_rt_put(rt); <------><------>return ERR_PTR(-ELOOP); <------>} #ifdef CONFIG_DST_CACHE <------>if (use_cache) <------><------>dst_cache_set_ip4(dst_cache, &rt->dst, fl4.saddr); #endif <------>*saddr = fl4.saddr; <------>return rt; } EXPORT_SYMBOL_GPL(ip_route_output_tunnel); /* called with rcu_read_lock held */ static int rt_fill_info(struct net *net, __be32 dst, __be32 src, <------><------><------>struct rtable *rt, u32 table_id, struct flowi4 *fl4, <------><------><------>struct sk_buff *skb, u32 portid, u32 seq, <------><------><------>unsigned int flags) { <------>struct rtmsg *r; <------>struct nlmsghdr *nlh; <------>unsigned long expires = 0; <------>u32 error; <------>u32 metrics[RTAX_MAX]; <------>nlh = nlmsg_put(skb, portid, seq, RTM_NEWROUTE, sizeof(*r), flags); <------>if (!nlh) <------><------>return -EMSGSIZE; <------>r = nlmsg_data(nlh); <------>r->rtm_family = AF_INET; <------>r->rtm_dst_len = 32; <------>r->rtm_src_len = 0; <------>r->rtm_tos = fl4 ? fl4->flowi4_tos : 0; <------>r->rtm_table = table_id < 256 ? table_id : RT_TABLE_COMPAT; <------>if (nla_put_u32(skb, RTA_TABLE, table_id)) <------><------>goto nla_put_failure; <------>r->rtm_type = rt->rt_type; <------>r->rtm_scope = RT_SCOPE_UNIVERSE; <------>r->rtm_protocol = RTPROT_UNSPEC; <------>r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED; <------>if (rt->rt_flags & RTCF_NOTIFY) <------><------>r->rtm_flags |= RTM_F_NOTIFY; <------>if (IPCB(skb)->flags & IPSKB_DOREDIRECT) <------><------>r->rtm_flags |= RTCF_DOREDIRECT; <------>if (nla_put_in_addr(skb, RTA_DST, dst)) <------><------>goto nla_put_failure; <------>if (src) { <------><------>r->rtm_src_len = 32; <------><------>if (nla_put_in_addr(skb, RTA_SRC, src)) <------><------><------>goto nla_put_failure; <------>} <------>if (rt->dst.dev && <------> nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex)) <------><------>goto nla_put_failure; #ifdef CONFIG_IP_ROUTE_CLASSID <------>if (rt->dst.tclassid && <------> nla_put_u32(skb, RTA_FLOW, rt->dst.tclassid)) <------><------>goto nla_put_failure; #endif <------>if (fl4 && !rt_is_input_route(rt) && <------> fl4->saddr != src) { <------><------>if (nla_put_in_addr(skb, RTA_PREFSRC, fl4->saddr)) <------><------><------>goto nla_put_failure; <------>} <------>if (rt->rt_uses_gateway) { <------><------>if (rt->rt_gw_family == AF_INET && <------><------> nla_put_in_addr(skb, RTA_GATEWAY, rt->rt_gw4)) { <------><------><------>goto nla_put_failure; <------><------>} else if (rt->rt_gw_family == AF_INET6) { <------><------><------>int alen = sizeof(struct in6_addr); <------><------><------>struct nlattr *nla; <------><------><------>struct rtvia *via; <------><------><------>nla = nla_reserve(skb, RTA_VIA, alen + 2); <------><------><------>if (!nla) <------><------><------><------>goto nla_put_failure; <------><------><------>via = nla_data(nla); <------><------><------>via->rtvia_family = AF_INET6; <------><------><------>memcpy(via->rtvia_addr, &rt->rt_gw6, alen); <------><------>} <------>} <------>expires = rt->dst.expires; <------>if (expires) { <------><------>unsigned long now = jiffies; <------><------>if (time_before(now, expires)) <------><------><------>expires -= now; <------><------>else <------><------><------>expires = 0; <------>} <------>memcpy(metrics, dst_metrics_ptr(&rt->dst), sizeof(metrics)); <------>if (rt->rt_pmtu && expires) <------><------>metrics[RTAX_MTU - 1] = rt->rt_pmtu; <------>if (rt->rt_mtu_locked && expires) <------><------>metrics[RTAX_LOCK - 1] |= BIT(RTAX_MTU); <------>if (rtnetlink_put_metrics(skb, metrics) < 0) <------><------>goto nla_put_failure; <------>if (fl4) { <------><------>if (fl4->flowi4_mark && <------><------> nla_put_u32(skb, RTA_MARK, fl4->flowi4_mark)) <------><------><------>goto nla_put_failure; <------><------>if (!uid_eq(fl4->flowi4_uid, INVALID_UID) && <------><------> nla_put_u32(skb, RTA_UID, <------><------><------><------>from_kuid_munged(current_user_ns(), <------><------><------><------><------><------> fl4->flowi4_uid))) <------><------><------>goto nla_put_failure; <------><------>if (rt_is_input_route(rt)) { #ifdef CONFIG_IP_MROUTE <------><------><------>if (ipv4_is_multicast(dst) && <------><------><------> !ipv4_is_local_multicast(dst) && <------><------><------> IPV4_DEVCONF_ALL(net, MC_FORWARDING)) { <------><------><------><------>int err = ipmr_get_route(net, skb, <------><------><------><------><------><------><------> fl4->saddr, fl4->daddr, <------><------><------><------><------><------><------> r, portid); <------><------><------><------>if (err <= 0) { <------><------><------><------><------>if (err == 0) <------><------><------><------><------><------>return 0; <------><------><------><------><------>goto nla_put_failure; <------><------><------><------>} <------><------><------>} else #endif <------><------><------><------>if (nla_put_u32(skb, RTA_IIF, fl4->flowi4_iif)) <------><------><------><------><------>goto nla_put_failure; <------><------>} <------>} <------>error = rt->dst.error; <------>if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires, error) < 0) <------><------>goto nla_put_failure; <------>nlmsg_end(skb, nlh); <------>return 0; nla_put_failure: <------>nlmsg_cancel(skb, nlh); <------>return -EMSGSIZE; } static int fnhe_dump_bucket(struct net *net, struct sk_buff *skb, <------><------><------> struct netlink_callback *cb, u32 table_id, <------><------><------> struct fnhe_hash_bucket *bucket, int genid, <------><------><------> int *fa_index, int fa_start, unsigned int flags) { <------>int i; <------>for (i = 0; i < FNHE_HASH_SIZE; i++) { <------><------>struct fib_nh_exception *fnhe; <------><------>for (fnhe = rcu_dereference(bucket[i].chain); fnhe; <------><------> fnhe = rcu_dereference(fnhe->fnhe_next)) { <------><------><------>struct rtable *rt; <------><------><------>int err; <------><------><------>if (*fa_index < fa_start) <------><------><------><------>goto next; <------><------><------>if (fnhe->fnhe_genid != genid) <------><------><------><------>goto next; <------><------><------>if (fnhe->fnhe_expires && <------><------><------> time_after(jiffies, fnhe->fnhe_expires)) <------><------><------><------>goto next; <------><------><------>rt = rcu_dereference(fnhe->fnhe_rth_input); <------><------><------>if (!rt) <------><------><------><------>rt = rcu_dereference(fnhe->fnhe_rth_output); <------><------><------>if (!rt) <------><------><------><------>goto next; <------><------><------>err = rt_fill_info(net, fnhe->fnhe_daddr, 0, rt, <------><------><------><------><------> table_id, NULL, skb, <------><------><------><------><------> NETLINK_CB(cb->skb).portid, <------><------><------><------><------> cb->nlh->nlmsg_seq, flags); <------><------><------>if (err) <------><------><------><------>return err; next: <------><------><------>(*fa_index)++; <------><------>} <------>} <------>return 0; } int fib_dump_info_fnhe(struct sk_buff *skb, struct netlink_callback *cb, <------><------> u32 table_id, struct fib_info *fi, <------><------> int *fa_index, int fa_start, unsigned int flags) { <------>struct net *net = sock_net(cb->skb->sk); <------>int nhsel, genid = fnhe_genid(net); <------>for (nhsel = 0; nhsel < fib_info_num_path(fi); nhsel++) { <------><------>struct fib_nh_common *nhc = fib_info_nhc(fi, nhsel); <------><------>struct fnhe_hash_bucket *bucket; <------><------>int err; <------><------>if (nhc->nhc_flags & RTNH_F_DEAD) <------><------><------>continue; <------><------>rcu_read_lock(); <------><------>bucket = rcu_dereference(nhc->nhc_exceptions); <------><------>err = 0; <------><------>if (bucket) <------><------><------>err = fnhe_dump_bucket(net, skb, cb, table_id, bucket, <------><------><------><------><------> genid, fa_index, fa_start, <------><------><------><------><------> flags); <------><------>rcu_read_unlock(); <------><------>if (err) <------><------><------>return err; <------>} <------>return 0; } static struct sk_buff *inet_rtm_getroute_build_skb(__be32 src, __be32 dst, <------><------><------><------><------><------> u8 ip_proto, __be16 sport, <------><------><------><------><------><------> __be16 dport) { <------>struct sk_buff *skb; <------>struct iphdr *iph; <------>skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); <------>if (!skb) <------><------>return NULL; <------>/* Reserve room for dummy headers, this skb can pass <------> * through good chunk of routing engine. <------> */ <------>skb_reset_mac_header(skb); <------>skb_reset_network_header(skb); <------>skb->protocol = htons(ETH_P_IP); <------>iph = skb_put(skb, sizeof(struct iphdr)); <------>iph->protocol = ip_proto; <------>iph->saddr = src; <------>iph->daddr = dst; <------>iph->version = 0x4; <------>iph->frag_off = 0; <------>iph->ihl = 0x5; <------>skb_set_transport_header(skb, skb->len); <------>switch (iph->protocol) { <------>case IPPROTO_UDP: { <------><------>struct udphdr *udph; <------><------>udph = skb_put_zero(skb, sizeof(struct udphdr)); <------><------>udph->source = sport; <------><------>udph->dest = dport; <------><------>udph->len = htons(sizeof(struct udphdr)); <------><------>udph->check = 0; <------><------>break; <------>} <------>case IPPROTO_TCP: { <------><------>struct tcphdr *tcph; <------><------>tcph = skb_put_zero(skb, sizeof(struct tcphdr)); <------><------>tcph->source = sport; <------><------>tcph->dest = dport; <------><------>tcph->doff = sizeof(struct tcphdr) / 4; <------><------>tcph->rst = 1; <------><------>tcph->check = ~tcp_v4_check(sizeof(struct tcphdr), <------><------><------><------><------> src, dst, 0); <------><------>break; <------>} <------>case IPPROTO_ICMP: { <------><------>struct icmphdr *icmph; <------><------>icmph = skb_put_zero(skb, sizeof(struct icmphdr)); <------><------>icmph->type = ICMP_ECHO; <------><------>icmph->code = 0; <------>} <------>} <------>return skb; } static int inet_rtm_valid_getroute_req(struct sk_buff *skb, <------><------><------><------> const struct nlmsghdr *nlh, <------><------><------><------> struct nlattr **tb, <------><------><------><------> struct netlink_ext_ack *extack) { <------>struct rtmsg *rtm; <------>int i, err; <------>if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*rtm))) { <------><------>NL_SET_ERR_MSG(extack, <------><------><------> "ipv4: Invalid header for route get request"); <------><------>return -EINVAL; <------>} <------>if (!netlink_strict_get_check(skb)) <------><------>return nlmsg_parse_deprecated(nlh, sizeof(*rtm), tb, RTA_MAX, <------><------><------><------><------> rtm_ipv4_policy, extack); <------>rtm = nlmsg_data(nlh); <------>if ((rtm->rtm_src_len && rtm->rtm_src_len != 32) || <------> (rtm->rtm_dst_len && rtm->rtm_dst_len != 32) || <------> rtm->rtm_table || rtm->rtm_protocol || <------> rtm->rtm_scope || rtm->rtm_type) { <------><------>NL_SET_ERR_MSG(extack, "ipv4: Invalid values in header for route get request"); <------><------>return -EINVAL; <------>} <------>if (rtm->rtm_flags & ~(RTM_F_NOTIFY | <------><------><------> RTM_F_LOOKUP_TABLE | <------><------><------> RTM_F_FIB_MATCH)) { <------><------>NL_SET_ERR_MSG(extack, "ipv4: Unsupported rtm_flags for route get request"); <------><------>return -EINVAL; <------>} <------>err = nlmsg_parse_deprecated_strict(nlh, sizeof(*rtm), tb, RTA_MAX, <------><------><------><------><------> rtm_ipv4_policy, extack); <------>if (err) <------><------>return err; <------>if ((tb[RTA_SRC] && !rtm->rtm_src_len) || <------> (tb[RTA_DST] && !rtm->rtm_dst_len)) { <------><------>NL_SET_ERR_MSG(extack, "ipv4: rtm_src_len and rtm_dst_len must be 32 for IPv4"); <------><------>return -EINVAL; <------>} <------>for (i = 0; i <= RTA_MAX; i++) { <------><------>if (!tb[i]) <------><------><------>continue; <------><------>switch (i) { <------><------>case RTA_IIF: <------><------>case RTA_OIF: <------><------>case RTA_SRC: <------><------>case RTA_DST: <------><------>case RTA_IP_PROTO: <------><------>case RTA_SPORT: <------><------>case RTA_DPORT: <------><------>case RTA_MARK: <------><------>case RTA_UID: <------><------><------>break; <------><------>default: <------><------><------>NL_SET_ERR_MSG(extack, "ipv4: Unsupported attribute in route get request"); <------><------><------>return -EINVAL; <------><------>} <------>} <------>return 0; } static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, <------><------><------> struct netlink_ext_ack *extack) { <------>struct net *net = sock_net(in_skb->sk); <------>struct nlattr *tb[RTA_MAX+1]; <------>u32 table_id = RT_TABLE_MAIN; <------>__be16 sport = 0, dport = 0; <------>struct fib_result res = {}; <------>u8 ip_proto = IPPROTO_UDP; <------>struct rtable *rt = NULL; <------>struct sk_buff *skb; <------>struct rtmsg *rtm; <------>struct flowi4 fl4 = {}; <------>__be32 dst = 0; <------>__be32 src = 0; <------>kuid_t uid; <------>u32 iif; <------>int err; <------>int mark; <------>err = inet_rtm_valid_getroute_req(in_skb, nlh, tb, extack); <------>if (err < 0) <------><------>return err; <------>rtm = nlmsg_data(nlh); <------>src = tb[RTA_SRC] ? nla_get_in_addr(tb[RTA_SRC]) : 0; <------>dst = tb[RTA_DST] ? nla_get_in_addr(tb[RTA_DST]) : 0; <------>iif = tb[RTA_IIF] ? nla_get_u32(tb[RTA_IIF]) : 0; <------>mark = tb[RTA_MARK] ? nla_get_u32(tb[RTA_MARK]) : 0; <------>if (tb[RTA_UID]) <------><------>uid = make_kuid(current_user_ns(), nla_get_u32(tb[RTA_UID])); <------>else <------><------>uid = (iif ? INVALID_UID : current_uid()); <------>if (tb[RTA_IP_PROTO]) { <------><------>err = rtm_getroute_parse_ip_proto(tb[RTA_IP_PROTO], <------><------><------><------><------><------> &ip_proto, AF_INET, extack); <------><------>if (err) <------><------><------>return err; <------>} <------>if (tb[RTA_SPORT]) <------><------>sport = nla_get_be16(tb[RTA_SPORT]); <------>if (tb[RTA_DPORT]) <------><------>dport = nla_get_be16(tb[RTA_DPORT]); <------>skb = inet_rtm_getroute_build_skb(src, dst, ip_proto, sport, dport); <------>if (!skb) <------><------>return -ENOBUFS; <------>fl4.daddr = dst; <------>fl4.saddr = src; <------>fl4.flowi4_tos = rtm->rtm_tos & IPTOS_RT_MASK; <------>fl4.flowi4_oif = tb[RTA_OIF] ? nla_get_u32(tb[RTA_OIF]) : 0; <------>fl4.flowi4_mark = mark; <------>fl4.flowi4_uid = uid; <------>if (sport) <------><------>fl4.fl4_sport = sport; <------>if (dport) <------><------>fl4.fl4_dport = dport; <------>fl4.flowi4_proto = ip_proto; <------>rcu_read_lock(); <------>if (iif) { <------><------>struct net_device *dev; <------><------>dev = dev_get_by_index_rcu(net, iif); <------><------>if (!dev) { <------><------><------>err = -ENODEV; <------><------><------>goto errout_rcu; <------><------>} <------><------>fl4.flowi4_iif = iif; /* for rt_fill_info */ <------><------>skb->dev = dev; <------><------>skb->mark = mark; <------><------>err = ip_route_input_rcu(skb, dst, src, <------><------><------><------><------> rtm->rtm_tos & IPTOS_RT_MASK, dev, <------><------><------><------><------> &res); <------><------>rt = skb_rtable(skb); <------><------>if (err == 0 && rt->dst.error) <------><------><------>err = -rt->dst.error; <------>} else { <------><------>fl4.flowi4_iif = LOOPBACK_IFINDEX; <------><------>skb->dev = net->loopback_dev; <------><------>rt = ip_route_output_key_hash_rcu(net, &fl4, &res, skb); <------><------>err = 0; <------><------>if (IS_ERR(rt)) <------><------><------>err = PTR_ERR(rt); <------><------>else <------><------><------>skb_dst_set(skb, &rt->dst); <------>} <------>if (err) <------><------>goto errout_rcu; <------>if (rtm->rtm_flags & RTM_F_NOTIFY) <------><------>rt->rt_flags |= RTCF_NOTIFY; <------>if (rtm->rtm_flags & RTM_F_LOOKUP_TABLE) <------><------>table_id = res.table ? res.table->tb_id : 0; <------>/* reset skb for netlink reply msg */ <------>skb_trim(skb, 0); <------>skb_reset_network_header(skb); <------>skb_reset_transport_header(skb); <------>skb_reset_mac_header(skb); <------>if (rtm->rtm_flags & RTM_F_FIB_MATCH) { <------><------>struct fib_rt_info fri; <------><------>if (!res.fi) { <------><------><------>err = fib_props[res.type].error; <------><------><------>if (!err) <------><------><------><------>err = -EHOSTUNREACH; <------><------><------>goto errout_rcu; <------><------>} <------><------>fri.fi = res.fi; <------><------>fri.tb_id = table_id; <------><------>fri.dst = res.prefix; <------><------>fri.dst_len = res.prefixlen; <------><------>fri.tos = fl4.flowi4_tos; <------><------>fri.type = rt->rt_type; <------><------>fri.offload = 0; <------><------>fri.trap = 0; <------><------>if (res.fa_head) { <------><------><------>struct fib_alias *fa; <------><------><------>hlist_for_each_entry_rcu(fa, res.fa_head, fa_list) { <------><------><------><------>u8 slen = 32 - fri.dst_len; <------><------><------><------>if (fa->fa_slen == slen && <------><------><------><------> fa->tb_id == fri.tb_id && <------><------><------><------> fa->fa_tos == fri.tos && <------><------><------><------> fa->fa_info == res.fi && <------><------><------><------> fa->fa_type == fri.type) { <------><------><------><------><------>fri.offload = fa->offload; <------><------><------><------><------>fri.trap = fa->trap; <------><------><------><------><------>break; <------><------><------><------>} <------><------><------>} <------><------>} <------><------>err = fib_dump_info(skb, NETLINK_CB(in_skb).portid, <------><------><------><------> nlh->nlmsg_seq, RTM_NEWROUTE, &fri, 0); <------>} else { <------><------>err = rt_fill_info(net, dst, src, rt, table_id, &fl4, skb, <------><------><------><------> NETLINK_CB(in_skb).portid, <------><------><------><------> nlh->nlmsg_seq, 0); <------>} <------>if (err < 0) <------><------>goto errout_rcu; <------>rcu_read_unlock(); <------>err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid); errout_free: <------>return err; errout_rcu: <------>rcu_read_unlock(); <------>kfree_skb(skb); <------>goto errout_free; } void ip_rt_multicast_event(struct in_device *in_dev) { <------>rt_cache_flush(dev_net(in_dev->dev)); } #ifdef CONFIG_SYSCTL static int ip_rt_gc_interval __read_mostly = 60 * HZ; static int ip_rt_gc_min_interval __read_mostly = HZ / 2; static int ip_rt_gc_elasticity __read_mostly = 8; static int ip_min_valid_pmtu __read_mostly = IPV4_MIN_MTU; static int ipv4_sysctl_rtcache_flush(struct ctl_table *__ctl, int write, <------><------>void *buffer, size_t *lenp, loff_t *ppos) { <------>struct net *net = (struct net *)__ctl->extra1; <------>if (write) { <------><------>rt_cache_flush(net); <------><------>fnhe_genid_bump(net); <------><------>return 0; <------>} <------>return -EINVAL; } static struct ctl_table ipv4_route_table[] = { <------>{ <------><------>.procname = "gc_thresh", <------><------>.data = &ipv4_dst_ops.gc_thresh, <------><------>.maxlen = sizeof(int), <------><------>.mode = 0644, <------><------>.proc_handler = proc_dointvec, <------>}, <------>{ <------><------>.procname = "max_size", <------><------>.data = &ip_rt_max_size, <------><------>.maxlen = sizeof(int), <------><------>.mode = 0644, <------><------>.proc_handler = proc_dointvec, <------>}, <------>{ <------><------>/* Deprecated. Use gc_min_interval_ms */ <------><------>.procname = "gc_min_interval", <------><------>.data = &ip_rt_gc_min_interval, <------><------>.maxlen = sizeof(int), <------><------>.mode = 0644, <------><------>.proc_handler = proc_dointvec_jiffies, <------>}, <------>{ <------><------>.procname = "gc_min_interval_ms", <------><------>.data = &ip_rt_gc_min_interval, <------><------>.maxlen = sizeof(int), <------><------>.mode = 0644, <------><------>.proc_handler = proc_dointvec_ms_jiffies, <------>}, <------>{ <------><------>.procname = "gc_timeout", <------><------>.data = &ip_rt_gc_timeout, <------><------>.maxlen = sizeof(int), <------><------>.mode = 0644, <------><------>.proc_handler = proc_dointvec_jiffies, <------>}, <------>{ <------><------>.procname = "gc_interval", <------><------>.data = &ip_rt_gc_interval, <------><------>.maxlen = sizeof(int), <------><------>.mode = 0644, <------><------>.proc_handler = proc_dointvec_jiffies, <------>}, <------>{ <------><------>.procname = "redirect_load", <------><------>.data = &ip_rt_redirect_load, <------><------>.maxlen = sizeof(int), <------><------>.mode = 0644, <------><------>.proc_handler = proc_dointvec, <------>}, <------>{ <------><------>.procname = "redirect_number", <------><------>.data = &ip_rt_redirect_number, <------><------>.maxlen = sizeof(int), <------><------>.mode = 0644, <------><------>.proc_handler = proc_dointvec, <------>}, <------>{ <------><------>.procname = "redirect_silence", <------><------>.data = &ip_rt_redirect_silence, <------><------>.maxlen = sizeof(int), <------><------>.mode = 0644, <------><------>.proc_handler = proc_dointvec, <------>}, <------>{ <------><------>.procname = "error_cost", <------><------>.data = &ip_rt_error_cost, <------><------>.maxlen = sizeof(int), <------><------>.mode = 0644, <------><------>.proc_handler = proc_dointvec, <------>}, <------>{ <------><------>.procname = "error_burst", <------><------>.data = &ip_rt_error_burst, <------><------>.maxlen = sizeof(int), <------><------>.mode = 0644, <------><------>.proc_handler = proc_dointvec, <------>}, <------>{ <------><------>.procname = "gc_elasticity", <------><------>.data = &ip_rt_gc_elasticity, <------><------>.maxlen = sizeof(int), <------><------>.mode = 0644, <------><------>.proc_handler = proc_dointvec, <------>}, <------>{ <------><------>.procname = "mtu_expires", <------><------>.data = &ip_rt_mtu_expires, <------><------>.maxlen = sizeof(int), <------><------>.mode = 0644, <------><------>.proc_handler = proc_dointvec_jiffies, <------>}, <------>{ <------><------>.procname = "min_pmtu", <------><------>.data = &ip_rt_min_pmtu, <------><------>.maxlen = sizeof(int), <------><------>.mode = 0644, <------><------>.proc_handler = proc_dointvec_minmax, <------><------>.extra1 = &ip_min_valid_pmtu, <------>}, <------>{ <------><------>.procname = "min_adv_mss", <------><------>.data = &ip_rt_min_advmss, <------><------>.maxlen = sizeof(int), <------><------>.mode = 0644, <------><------>.proc_handler = proc_dointvec, <------>}, <------>{ } }; static const char ipv4_route_flush_procname[] = "flush"; static struct ctl_table ipv4_route_flush_table[] = { <------>{ <------><------>.procname = ipv4_route_flush_procname, <------><------>.maxlen = sizeof(int), <------><------>.mode = 0200, <------><------>.proc_handler = ipv4_sysctl_rtcache_flush, <------>}, <------>{ }, }; static __net_init int sysctl_route_net_init(struct net *net) { <------>struct ctl_table *tbl; <------>tbl = ipv4_route_flush_table; <------>if (!net_eq(net, &init_net)) { <------><------>tbl = kmemdup(tbl, sizeof(ipv4_route_flush_table), GFP_KERNEL); <------><------>if (!tbl) <------><------><------>goto err_dup; <------><------>/* Don't export non-whitelisted sysctls to unprivileged users */ <------><------>if (net->user_ns != &init_user_ns) { <------><------><------>if (tbl[0].procname != ipv4_route_flush_procname) <------><------><------><------>tbl[0].procname = NULL; <------><------>} <------>} <------>tbl[0].extra1 = net; <------>net->ipv4.route_hdr = register_net_sysctl(net, "net/ipv4/route", tbl); <------>if (!net->ipv4.route_hdr) <------><------>goto err_reg; <------>return 0; err_reg: <------>if (tbl != ipv4_route_flush_table) <------><------>kfree(tbl); err_dup: <------>return -ENOMEM; } static __net_exit void sysctl_route_net_exit(struct net *net) { <------>struct ctl_table *tbl; <------>tbl = net->ipv4.route_hdr->ctl_table_arg; <------>unregister_net_sysctl_table(net->ipv4.route_hdr); <------>BUG_ON(tbl == ipv4_route_flush_table); <------>kfree(tbl); } static __net_initdata struct pernet_operations sysctl_route_ops = { <------>.init = sysctl_route_net_init, <------>.exit = sysctl_route_net_exit, }; #endif static __net_init int rt_genid_init(struct net *net) { <------>atomic_set(&net->ipv4.rt_genid, 0); <------>atomic_set(&net->fnhe_genid, 0); <------>atomic_set(&net->ipv4.dev_addr_genid, get_random_int()); <------>return 0; } static __net_initdata struct pernet_operations rt_genid_ops = { <------>.init = rt_genid_init, }; static int __net_init ipv4_inetpeer_init(struct net *net) { <------>struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL); <------>if (!bp) <------><------>return -ENOMEM; <------>inet_peer_base_init(bp); <------>net->ipv4.peers = bp; <------>return 0; } static void __net_exit ipv4_inetpeer_exit(struct net *net) { <------>struct inet_peer_base *bp = net->ipv4.peers; <------>net->ipv4.peers = NULL; <------>inetpeer_invalidate_tree(bp); <------>kfree(bp); } static __net_initdata struct pernet_operations ipv4_inetpeer_ops = { <------>.init = ipv4_inetpeer_init, <------>.exit = ipv4_inetpeer_exit, }; #ifdef CONFIG_IP_ROUTE_CLASSID struct ip_rt_acct __percpu *ip_rt_acct __read_mostly; #endif /* CONFIG_IP_ROUTE_CLASSID */ int __init ip_rt_init(void) { <------>void *idents_hash; <------>int cpu; <------>/* For modern hosts, this will use 2 MB of memory */ <------>idents_hash = alloc_large_system_hash("IP idents", <------><------><------><------><------> sizeof(*ip_idents) + sizeof(*ip_tstamps), <------><------><------><------><------> 0, <------><------><------><------><------> 16, /* one bucket per 64 KB */ <------><------><------><------><------> HASH_ZERO, <------><------><------><------><------> NULL, <------><------><------><------><------> &ip_idents_mask, <------><------><------><------><------> 2048, <------><------><------><------><------> 256*1024); <------>ip_idents = idents_hash; <------>prandom_bytes(ip_idents, (ip_idents_mask + 1) * sizeof(*ip_idents)); <------>ip_tstamps = idents_hash + (ip_idents_mask + 1) * sizeof(*ip_idents); <------>for_each_possible_cpu(cpu) { <------><------>struct uncached_list *ul = &per_cpu(rt_uncached_list, cpu); <------><------>INIT_LIST_HEAD(&ul->head); <------><------>spin_lock_init(&ul->lock); <------>} #ifdef CONFIG_IP_ROUTE_CLASSID <------>ip_rt_acct = __alloc_percpu(256 * sizeof(struct ip_rt_acct), __alignof__(struct ip_rt_acct)); <------>if (!ip_rt_acct) <------><------>panic("IP: failed to allocate ip_rt_acct\n"); #endif <------>ipv4_dst_ops.kmem_cachep = <------><------>kmem_cache_create("ip_dst_cache", sizeof(struct rtable), 0, <------><------><------><------> SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL); <------>ipv4_dst_blackhole_ops.kmem_cachep = ipv4_dst_ops.kmem_cachep; <------>if (dst_entries_init(&ipv4_dst_ops) < 0) <------><------>panic("IP: failed to allocate ipv4_dst_ops counter\n"); <------>if (dst_entries_init(&ipv4_dst_blackhole_ops) < 0) <------><------>panic("IP: failed to allocate ipv4_dst_blackhole_ops counter\n"); <------>ipv4_dst_ops.gc_thresh = ~0; <------>ip_rt_max_size = INT_MAX; <------>devinet_init(); <------>ip_fib_init(); <------>if (ip_rt_proc_init()) <------><------>pr_err("Unable to create route proc files\n"); #ifdef CONFIG_XFRM <------>xfrm_init(); <------>xfrm4_init(); #endif <------>rtnl_register(PF_INET, RTM_GETROUTE, inet_rtm_getroute, NULL, <------><------> RTNL_FLAG_DOIT_UNLOCKED); #ifdef CONFIG_SYSCTL <------>register_pernet_subsys(&sysctl_route_ops); #endif <------>register_pernet_subsys(&rt_genid_ops); <------>register_pernet_subsys(&ipv4_inetpeer_ops); <------>return 0; } #ifdef CONFIG_SYSCTL /* * We really need to sanitize the damn ipv4 init order, then all * this nonsense will go away. */ void __init ip_static_sysctl_init(void) { <------>register_net_sysctl(&init_net, "net/ipv4/route", ipv4_route_table); } #endif
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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