11da177e4SLinus Torvalds /* 21da177e4SLinus Torvalds * INET An implementation of the TCP/IP protocol suite for the LINUX 31da177e4SLinus Torvalds * operating system. INET is implemented using the BSD Socket 41da177e4SLinus Torvalds * interface as the means of communication with the user level. 51da177e4SLinus Torvalds * 61da177e4SLinus Torvalds * IPv4 Forwarding Information Base: semantics. 71da177e4SLinus Torvalds * 81da177e4SLinus Torvalds * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> 91da177e4SLinus Torvalds * 101da177e4SLinus Torvalds * This program is free software; you can redistribute it and/or 111da177e4SLinus Torvalds * modify it under the terms of the GNU General Public License 121da177e4SLinus Torvalds * as published by the Free Software Foundation; either version 131da177e4SLinus Torvalds * 2 of the License, or (at your option) any later version. 141da177e4SLinus Torvalds */ 151da177e4SLinus Torvalds 161da177e4SLinus Torvalds #include <asm/uaccess.h> 171da177e4SLinus Torvalds #include <linux/bitops.h> 181da177e4SLinus Torvalds #include <linux/types.h> 191da177e4SLinus Torvalds #include <linux/kernel.h> 201da177e4SLinus Torvalds #include <linux/jiffies.h> 211da177e4SLinus Torvalds #include <linux/mm.h> 221da177e4SLinus Torvalds #include <linux/string.h> 231da177e4SLinus Torvalds #include <linux/socket.h> 241da177e4SLinus Torvalds #include <linux/sockios.h> 251da177e4SLinus Torvalds #include <linux/errno.h> 261da177e4SLinus Torvalds #include <linux/in.h> 271da177e4SLinus Torvalds #include <linux/inet.h> 2814c85021SArnaldo Carvalho de Melo #include <linux/inetdevice.h> 291da177e4SLinus Torvalds #include <linux/netdevice.h> 301da177e4SLinus Torvalds #include <linux/if_arp.h> 311da177e4SLinus Torvalds #include <linux/proc_fs.h> 321da177e4SLinus Torvalds #include <linux/skbuff.h> 331da177e4SLinus Torvalds #include <linux/init.h> 345a0e3ad6STejun Heo #include <linux/slab.h> 351da177e4SLinus Torvalds 3614c85021SArnaldo Carvalho de Melo #include <net/arp.h> 371da177e4SLinus Torvalds #include <net/ip.h> 381da177e4SLinus Torvalds #include <net/protocol.h> 391da177e4SLinus Torvalds #include <net/route.h> 401da177e4SLinus Torvalds #include <net/tcp.h> 411da177e4SLinus Torvalds #include <net/sock.h> 421da177e4SLinus Torvalds #include <net/ip_fib.h> 43f21c7bc5SThomas Graf #include <net/netlink.h> 444e902c57SThomas Graf #include <net/nexthop.h> 451da177e4SLinus Torvalds 461da177e4SLinus Torvalds #include "fib_lookup.h" 471da177e4SLinus Torvalds 48832b4c5eSStephen Hemminger static DEFINE_SPINLOCK(fib_info_lock); 491da177e4SLinus Torvalds static struct hlist_head *fib_info_hash; 501da177e4SLinus Torvalds static struct hlist_head *fib_info_laddrhash; 51123b9731SDavid S. Miller static unsigned int fib_info_hash_size; 521da177e4SLinus Torvalds static unsigned int fib_info_cnt; 531da177e4SLinus Torvalds 541da177e4SLinus Torvalds #define DEVINDEX_HASHBITS 8 551da177e4SLinus Torvalds #define DEVINDEX_HASHSIZE (1U << DEVINDEX_HASHBITS) 561da177e4SLinus Torvalds static struct hlist_head fib_info_devhash[DEVINDEX_HASHSIZE]; 571da177e4SLinus Torvalds 581da177e4SLinus Torvalds #ifdef CONFIG_IP_ROUTE_MULTIPATH 591da177e4SLinus Torvalds 601da177e4SLinus Torvalds static DEFINE_SPINLOCK(fib_multipath_lock); 611da177e4SLinus Torvalds 626a31d2a9SEric Dumazet #define for_nexthops(fi) { \ 636a31d2a9SEric Dumazet int nhsel; const struct fib_nh *nh; \ 646a31d2a9SEric Dumazet for (nhsel = 0, nh = (fi)->fib_nh; \ 656a31d2a9SEric Dumazet nhsel < (fi)->fib_nhs; \ 666a31d2a9SEric Dumazet nh++, nhsel++) 671da177e4SLinus Torvalds 686a31d2a9SEric Dumazet #define change_nexthops(fi) { \ 696a31d2a9SEric Dumazet int nhsel; struct fib_nh *nexthop_nh; \ 706a31d2a9SEric Dumazet for (nhsel = 0, nexthop_nh = (struct fib_nh *)((fi)->fib_nh); \ 716a31d2a9SEric Dumazet nhsel < (fi)->fib_nhs; \ 726a31d2a9SEric Dumazet nexthop_nh++, nhsel++) 731da177e4SLinus Torvalds 741da177e4SLinus Torvalds #else /* CONFIG_IP_ROUTE_MULTIPATH */ 751da177e4SLinus Torvalds 761da177e4SLinus Torvalds /* Hope, that gcc will optimize it to get rid of dummy loop */ 771da177e4SLinus Torvalds 786a31d2a9SEric Dumazet #define for_nexthops(fi) { \ 796a31d2a9SEric Dumazet int nhsel; const struct fib_nh *nh = (fi)->fib_nh; \ 801da177e4SLinus Torvalds for (nhsel = 0; nhsel < 1; nhsel++) 811da177e4SLinus Torvalds 826a31d2a9SEric Dumazet #define change_nexthops(fi) { \ 836a31d2a9SEric Dumazet int nhsel; \ 846a31d2a9SEric Dumazet struct fib_nh *nexthop_nh = (struct fib_nh *)((fi)->fib_nh); \ 851da177e4SLinus Torvalds for (nhsel = 0; nhsel < 1; nhsel++) 861da177e4SLinus Torvalds 871da177e4SLinus Torvalds #endif /* CONFIG_IP_ROUTE_MULTIPATH */ 881da177e4SLinus Torvalds 891da177e4SLinus Torvalds #define endfor_nexthops(fi) } 901da177e4SLinus Torvalds 911da177e4SLinus Torvalds 923be0686bSDavid S. Miller const struct fib_prop fib_props[RTN_MAX + 1] = { 936a31d2a9SEric Dumazet [RTN_UNSPEC] = { 941da177e4SLinus Torvalds .error = 0, 951da177e4SLinus Torvalds .scope = RT_SCOPE_NOWHERE, 966a31d2a9SEric Dumazet }, 976a31d2a9SEric Dumazet [RTN_UNICAST] = { 981da177e4SLinus Torvalds .error = 0, 991da177e4SLinus Torvalds .scope = RT_SCOPE_UNIVERSE, 1006a31d2a9SEric Dumazet }, 1016a31d2a9SEric Dumazet [RTN_LOCAL] = { 1021da177e4SLinus Torvalds .error = 0, 1031da177e4SLinus Torvalds .scope = RT_SCOPE_HOST, 1046a31d2a9SEric Dumazet }, 1056a31d2a9SEric Dumazet [RTN_BROADCAST] = { 1061da177e4SLinus Torvalds .error = 0, 1071da177e4SLinus Torvalds .scope = RT_SCOPE_LINK, 1086a31d2a9SEric Dumazet }, 1096a31d2a9SEric Dumazet [RTN_ANYCAST] = { 1101da177e4SLinus Torvalds .error = 0, 1111da177e4SLinus Torvalds .scope = RT_SCOPE_LINK, 1126a31d2a9SEric Dumazet }, 1136a31d2a9SEric Dumazet [RTN_MULTICAST] = { 1141da177e4SLinus Torvalds .error = 0, 1151da177e4SLinus Torvalds .scope = RT_SCOPE_UNIVERSE, 1166a31d2a9SEric Dumazet }, 1176a31d2a9SEric Dumazet [RTN_BLACKHOLE] = { 1181da177e4SLinus Torvalds .error = -EINVAL, 1191da177e4SLinus Torvalds .scope = RT_SCOPE_UNIVERSE, 1206a31d2a9SEric Dumazet }, 1216a31d2a9SEric Dumazet [RTN_UNREACHABLE] = { 1221da177e4SLinus Torvalds .error = -EHOSTUNREACH, 1231da177e4SLinus Torvalds .scope = RT_SCOPE_UNIVERSE, 1246a31d2a9SEric Dumazet }, 1256a31d2a9SEric Dumazet [RTN_PROHIBIT] = { 1261da177e4SLinus Torvalds .error = -EACCES, 1271da177e4SLinus Torvalds .scope = RT_SCOPE_UNIVERSE, 1286a31d2a9SEric Dumazet }, 1296a31d2a9SEric Dumazet [RTN_THROW] = { 1301da177e4SLinus Torvalds .error = -EAGAIN, 1311da177e4SLinus Torvalds .scope = RT_SCOPE_UNIVERSE, 1326a31d2a9SEric Dumazet }, 1336a31d2a9SEric Dumazet [RTN_NAT] = { 1341da177e4SLinus Torvalds .error = -EINVAL, 1351da177e4SLinus Torvalds .scope = RT_SCOPE_NOWHERE, 1366a31d2a9SEric Dumazet }, 1376a31d2a9SEric Dumazet [RTN_XRESOLVE] = { 1381da177e4SLinus Torvalds .error = -EINVAL, 1391da177e4SLinus Torvalds .scope = RT_SCOPE_NOWHERE, 1406a31d2a9SEric Dumazet }, 1411da177e4SLinus Torvalds }; 1421da177e4SLinus Torvalds 1434895c771SDavid S. Miller static void free_nh_exceptions(struct fib_nh *nh) 1444895c771SDavid S. Miller { 1454895c771SDavid S. Miller struct fnhe_hash_bucket *hash = nh->nh_exceptions; 1464895c771SDavid S. Miller int i; 1474895c771SDavid S. Miller 1484895c771SDavid S. Miller for (i = 0; i < FNHE_HASH_SIZE; i++) { 1494895c771SDavid S. Miller struct fib_nh_exception *fnhe; 1504895c771SDavid S. Miller 1515abf7f7eSEric Dumazet fnhe = rcu_dereference_protected(hash[i].chain, 1); 1524895c771SDavid S. Miller while (fnhe) { 1534895c771SDavid S. Miller struct fib_nh_exception *next; 1544895c771SDavid S. Miller 1555abf7f7eSEric Dumazet next = rcu_dereference_protected(fnhe->fnhe_next, 1); 1564895c771SDavid S. Miller kfree(fnhe); 1574895c771SDavid S. Miller 1584895c771SDavid S. Miller fnhe = next; 1594895c771SDavid S. Miller } 1604895c771SDavid S. Miller } 1614895c771SDavid S. Miller kfree(hash); 1624895c771SDavid S. Miller } 1634895c771SDavid S. Miller 16454764bb6SEric Dumazet static void rt_nexthop_free(struct rtable __rcu **rtp) 16554764bb6SEric Dumazet { 16654764bb6SEric Dumazet struct rtable *rt = rcu_dereference_protected(*rtp, 1); 16754764bb6SEric Dumazet 16854764bb6SEric Dumazet if (!rt) 16954764bb6SEric Dumazet return; 17054764bb6SEric Dumazet 17154764bb6SEric Dumazet /* Not even needed : RCU_INIT_POINTER(*rtp, NULL); 17254764bb6SEric Dumazet * because we waited an RCU grace period before calling 17354764bb6SEric Dumazet * free_fib_info_rcu() 17454764bb6SEric Dumazet */ 17554764bb6SEric Dumazet 17654764bb6SEric Dumazet dst_free(&rt->dst); 17754764bb6SEric Dumazet } 17854764bb6SEric Dumazet 179*d26b3a7cSEric Dumazet static void rt_nexthop_free_cpus(struct rtable __rcu * __percpu *rtp) 180*d26b3a7cSEric Dumazet { 181*d26b3a7cSEric Dumazet int cpu; 182*d26b3a7cSEric Dumazet 183*d26b3a7cSEric Dumazet if (!rtp) 184*d26b3a7cSEric Dumazet return; 185*d26b3a7cSEric Dumazet 186*d26b3a7cSEric Dumazet for_each_possible_cpu(cpu) { 187*d26b3a7cSEric Dumazet struct rtable *rt; 188*d26b3a7cSEric Dumazet 189*d26b3a7cSEric Dumazet rt = rcu_dereference_protected(*per_cpu_ptr(rtp, cpu), 1); 190*d26b3a7cSEric Dumazet if (rt) 191*d26b3a7cSEric Dumazet dst_free(&rt->dst); 192*d26b3a7cSEric Dumazet } 193*d26b3a7cSEric Dumazet free_percpu(rtp); 194*d26b3a7cSEric Dumazet } 195*d26b3a7cSEric Dumazet 1961da177e4SLinus Torvalds /* Release a nexthop info record */ 19719c1ea14SYan, Zheng static void free_fib_info_rcu(struct rcu_head *head) 19819c1ea14SYan, Zheng { 19919c1ea14SYan, Zheng struct fib_info *fi = container_of(head, struct fib_info, rcu); 20019c1ea14SYan, Zheng 201e49cc0daSYanmin Zhang change_nexthops(fi) { 202e49cc0daSYanmin Zhang if (nexthop_nh->nh_dev) 203e49cc0daSYanmin Zhang dev_put(nexthop_nh->nh_dev); 2044895c771SDavid S. Miller if (nexthop_nh->nh_exceptions) 2054895c771SDavid S. Miller free_nh_exceptions(nexthop_nh); 206*d26b3a7cSEric Dumazet rt_nexthop_free_cpus(nexthop_nh->nh_pcpu_rth_output); 20754764bb6SEric Dumazet rt_nexthop_free(&nexthop_nh->nh_rth_input); 208e49cc0daSYanmin Zhang } endfor_nexthops(fi); 209e49cc0daSYanmin Zhang 210e49cc0daSYanmin Zhang release_net(fi->fib_net); 21119c1ea14SYan, Zheng if (fi->fib_metrics != (u32 *) dst_default_metrics) 21219c1ea14SYan, Zheng kfree(fi->fib_metrics); 21319c1ea14SYan, Zheng kfree(fi); 21419c1ea14SYan, Zheng } 2151da177e4SLinus Torvalds 2161da177e4SLinus Torvalds void free_fib_info(struct fib_info *fi) 2171da177e4SLinus Torvalds { 2181da177e4SLinus Torvalds if (fi->fib_dead == 0) { 219058bd4d2SJoe Perches pr_warn("Freeing alive fib_info %p\n", fi); 2201da177e4SLinus Torvalds return; 2211da177e4SLinus Torvalds } 2221da177e4SLinus Torvalds fib_info_cnt--; 2237a9bc9b8SDavid S. Miller #ifdef CONFIG_IP_ROUTE_CLASSID 2247a9bc9b8SDavid S. Miller change_nexthops(fi) { 2257a9bc9b8SDavid S. Miller if (nexthop_nh->nh_tclassid) 226f4530fa5SDavid S. Miller fi->fib_net->ipv4.fib_num_tclassid_users--; 2277a9bc9b8SDavid S. Miller } endfor_nexthops(fi); 2287a9bc9b8SDavid S. Miller #endif 22919c1ea14SYan, Zheng call_rcu(&fi->rcu, free_fib_info_rcu); 2301da177e4SLinus Torvalds } 2311da177e4SLinus Torvalds 2321da177e4SLinus Torvalds void fib_release_info(struct fib_info *fi) 2331da177e4SLinus Torvalds { 234832b4c5eSStephen Hemminger spin_lock_bh(&fib_info_lock); 2351da177e4SLinus Torvalds if (fi && --fi->fib_treeref == 0) { 2361da177e4SLinus Torvalds hlist_del(&fi->fib_hash); 2371da177e4SLinus Torvalds if (fi->fib_prefsrc) 2381da177e4SLinus Torvalds hlist_del(&fi->fib_lhash); 2391da177e4SLinus Torvalds change_nexthops(fi) { 24071fceff0SDavid S. Miller if (!nexthop_nh->nh_dev) 2411da177e4SLinus Torvalds continue; 24271fceff0SDavid S. Miller hlist_del(&nexthop_nh->nh_hash); 2431da177e4SLinus Torvalds } endfor_nexthops(fi) 2441da177e4SLinus Torvalds fi->fib_dead = 1; 2451da177e4SLinus Torvalds fib_info_put(fi); 2461da177e4SLinus Torvalds } 247832b4c5eSStephen Hemminger spin_unlock_bh(&fib_info_lock); 2481da177e4SLinus Torvalds } 2491da177e4SLinus Torvalds 2506a31d2a9SEric Dumazet static inline int nh_comp(const struct fib_info *fi, const struct fib_info *ofi) 2511da177e4SLinus Torvalds { 2521da177e4SLinus Torvalds const struct fib_nh *onh = ofi->fib_nh; 2531da177e4SLinus Torvalds 2541da177e4SLinus Torvalds for_nexthops(fi) { 2551da177e4SLinus Torvalds if (nh->nh_oif != onh->nh_oif || 2561da177e4SLinus Torvalds nh->nh_gw != onh->nh_gw || 2571da177e4SLinus Torvalds nh->nh_scope != onh->nh_scope || 2581da177e4SLinus Torvalds #ifdef CONFIG_IP_ROUTE_MULTIPATH 2591da177e4SLinus Torvalds nh->nh_weight != onh->nh_weight || 2601da177e4SLinus Torvalds #endif 261c7066f70SPatrick McHardy #ifdef CONFIG_IP_ROUTE_CLASSID 2621da177e4SLinus Torvalds nh->nh_tclassid != onh->nh_tclassid || 2631da177e4SLinus Torvalds #endif 2641da177e4SLinus Torvalds ((nh->nh_flags ^ onh->nh_flags) & ~RTNH_F_DEAD)) 2651da177e4SLinus Torvalds return -1; 2661da177e4SLinus Torvalds onh++; 2671da177e4SLinus Torvalds } endfor_nexthops(fi); 2681da177e4SLinus Torvalds return 0; 2691da177e4SLinus Torvalds } 2701da177e4SLinus Torvalds 27188ebc72fSDavid S. Miller static inline unsigned int fib_devindex_hashfn(unsigned int val) 27288ebc72fSDavid S. Miller { 27388ebc72fSDavid S. Miller unsigned int mask = DEVINDEX_HASHSIZE - 1; 27488ebc72fSDavid S. Miller 27588ebc72fSDavid S. Miller return (val ^ 27688ebc72fSDavid S. Miller (val >> DEVINDEX_HASHBITS) ^ 27788ebc72fSDavid S. Miller (val >> (DEVINDEX_HASHBITS * 2))) & mask; 27888ebc72fSDavid S. Miller } 27988ebc72fSDavid S. Miller 2801da177e4SLinus Torvalds static inline unsigned int fib_info_hashfn(const struct fib_info *fi) 2811da177e4SLinus Torvalds { 282123b9731SDavid S. Miller unsigned int mask = (fib_info_hash_size - 1); 2831da177e4SLinus Torvalds unsigned int val = fi->fib_nhs; 2841da177e4SLinus Torvalds 28537e826c5SDavid S. Miller val ^= (fi->fib_protocol << 8) | fi->fib_scope; 28681f7bf6cSAl Viro val ^= (__force u32)fi->fib_prefsrc; 2871da177e4SLinus Torvalds val ^= fi->fib_priority; 28888ebc72fSDavid S. Miller for_nexthops(fi) { 28988ebc72fSDavid S. Miller val ^= fib_devindex_hashfn(nh->nh_oif); 29088ebc72fSDavid S. Miller } endfor_nexthops(fi) 2911da177e4SLinus Torvalds 2921da177e4SLinus Torvalds return (val ^ (val >> 7) ^ (val >> 12)) & mask; 2931da177e4SLinus Torvalds } 2941da177e4SLinus Torvalds 2951da177e4SLinus Torvalds static struct fib_info *fib_find_info(const struct fib_info *nfi) 2961da177e4SLinus Torvalds { 2971da177e4SLinus Torvalds struct hlist_head *head; 2981da177e4SLinus Torvalds struct hlist_node *node; 2991da177e4SLinus Torvalds struct fib_info *fi; 3001da177e4SLinus Torvalds unsigned int hash; 3011da177e4SLinus Torvalds 3021da177e4SLinus Torvalds hash = fib_info_hashfn(nfi); 3031da177e4SLinus Torvalds head = &fib_info_hash[hash]; 3041da177e4SLinus Torvalds 3051da177e4SLinus Torvalds hlist_for_each_entry(fi, node, head, fib_hash) { 30609ad9bc7SOctavian Purdila if (!net_eq(fi->fib_net, nfi->fib_net)) 3074814bdbdSDenis V. Lunev continue; 3081da177e4SLinus Torvalds if (fi->fib_nhs != nfi->fib_nhs) 3091da177e4SLinus Torvalds continue; 3101da177e4SLinus Torvalds if (nfi->fib_protocol == fi->fib_protocol && 31137e826c5SDavid S. Miller nfi->fib_scope == fi->fib_scope && 3121da177e4SLinus Torvalds nfi->fib_prefsrc == fi->fib_prefsrc && 3131da177e4SLinus Torvalds nfi->fib_priority == fi->fib_priority && 3141da177e4SLinus Torvalds memcmp(nfi->fib_metrics, fi->fib_metrics, 315fcd13f42SEric Dumazet sizeof(u32) * RTAX_MAX) == 0 && 3161da177e4SLinus Torvalds ((nfi->fib_flags ^ fi->fib_flags) & ~RTNH_F_DEAD) == 0 && 3171da177e4SLinus Torvalds (nfi->fib_nhs == 0 || nh_comp(fi, nfi) == 0)) 3181da177e4SLinus Torvalds return fi; 3191da177e4SLinus Torvalds } 3201da177e4SLinus Torvalds 3211da177e4SLinus Torvalds return NULL; 3221da177e4SLinus Torvalds } 3231da177e4SLinus Torvalds 3241da177e4SLinus Torvalds /* Check, that the gateway is already configured. 3256a31d2a9SEric Dumazet * Used only by redirect accept routine. 3261da177e4SLinus Torvalds */ 327d878e72eSAl Viro int ip_fib_check_default(__be32 gw, struct net_device *dev) 3281da177e4SLinus Torvalds { 3291da177e4SLinus Torvalds struct hlist_head *head; 3301da177e4SLinus Torvalds struct hlist_node *node; 3311da177e4SLinus Torvalds struct fib_nh *nh; 3321da177e4SLinus Torvalds unsigned int hash; 3331da177e4SLinus Torvalds 334832b4c5eSStephen Hemminger spin_lock(&fib_info_lock); 3351da177e4SLinus Torvalds 3361da177e4SLinus Torvalds hash = fib_devindex_hashfn(dev->ifindex); 3371da177e4SLinus Torvalds head = &fib_info_devhash[hash]; 3381da177e4SLinus Torvalds hlist_for_each_entry(nh, node, head, nh_hash) { 3391da177e4SLinus Torvalds if (nh->nh_dev == dev && 3401da177e4SLinus Torvalds nh->nh_gw == gw && 3411da177e4SLinus Torvalds !(nh->nh_flags & RTNH_F_DEAD)) { 342832b4c5eSStephen Hemminger spin_unlock(&fib_info_lock); 3431da177e4SLinus Torvalds return 0; 3441da177e4SLinus Torvalds } 3451da177e4SLinus Torvalds } 3461da177e4SLinus Torvalds 347832b4c5eSStephen Hemminger spin_unlock(&fib_info_lock); 3481da177e4SLinus Torvalds 3491da177e4SLinus Torvalds return -1; 3501da177e4SLinus Torvalds } 3511da177e4SLinus Torvalds 352339bf98fSThomas Graf static inline size_t fib_nlmsg_size(struct fib_info *fi) 353339bf98fSThomas Graf { 354339bf98fSThomas Graf size_t payload = NLMSG_ALIGN(sizeof(struct rtmsg)) 355339bf98fSThomas Graf + nla_total_size(4) /* RTA_TABLE */ 356339bf98fSThomas Graf + nla_total_size(4) /* RTA_DST */ 357339bf98fSThomas Graf + nla_total_size(4) /* RTA_PRIORITY */ 358339bf98fSThomas Graf + nla_total_size(4); /* RTA_PREFSRC */ 359339bf98fSThomas Graf 360339bf98fSThomas Graf /* space for nested metrics */ 361339bf98fSThomas Graf payload += nla_total_size((RTAX_MAX * nla_total_size(4))); 362339bf98fSThomas Graf 363339bf98fSThomas Graf if (fi->fib_nhs) { 364339bf98fSThomas Graf /* Also handles the special case fib_nhs == 1 */ 365339bf98fSThomas Graf 366339bf98fSThomas Graf /* each nexthop is packed in an attribute */ 367339bf98fSThomas Graf size_t nhsize = nla_total_size(sizeof(struct rtnexthop)); 368339bf98fSThomas Graf 369339bf98fSThomas Graf /* may contain flow and gateway attribute */ 370339bf98fSThomas Graf nhsize += 2 * nla_total_size(4); 371339bf98fSThomas Graf 372339bf98fSThomas Graf /* all nexthops are packed in a nested attribute */ 373339bf98fSThomas Graf payload += nla_total_size(fi->fib_nhs * nhsize); 374339bf98fSThomas Graf } 375339bf98fSThomas Graf 376339bf98fSThomas Graf return payload; 377339bf98fSThomas Graf } 378339bf98fSThomas Graf 37981f7bf6cSAl Viro void rtmsg_fib(int event, __be32 key, struct fib_alias *fa, 380b8f55831SMilan Kocian int dst_len, u32 tb_id, struct nl_info *info, 381b8f55831SMilan Kocian unsigned int nlm_flags) 3821da177e4SLinus Torvalds { 3831da177e4SLinus Torvalds struct sk_buff *skb; 3844e902c57SThomas Graf u32 seq = info->nlh ? info->nlh->nlmsg_seq : 0; 385f21c7bc5SThomas Graf int err = -ENOBUFS; 3861da177e4SLinus Torvalds 387339bf98fSThomas Graf skb = nlmsg_new(fib_nlmsg_size(fa->fa_info), GFP_KERNEL); 388f21c7bc5SThomas Graf if (skb == NULL) 389f21c7bc5SThomas Graf goto errout; 3901da177e4SLinus Torvalds 3914e902c57SThomas Graf err = fib_dump_info(skb, info->pid, seq, event, tb_id, 39237e826c5SDavid S. Miller fa->fa_type, key, dst_len, 393b8f55831SMilan Kocian fa->fa_tos, fa->fa_info, nlm_flags); 39426932566SPatrick McHardy if (err < 0) { 39526932566SPatrick McHardy /* -EMSGSIZE implies BUG in fib_nlmsg_size() */ 39626932566SPatrick McHardy WARN_ON(err == -EMSGSIZE); 39726932566SPatrick McHardy kfree_skb(skb); 39826932566SPatrick McHardy goto errout; 39926932566SPatrick McHardy } 4001ce85fe4SPablo Neira Ayuso rtnl_notify(skb, info->nl_net, info->pid, RTNLGRP_IPV4_ROUTE, 4014e902c57SThomas Graf info->nlh, GFP_KERNEL); 4021ce85fe4SPablo Neira Ayuso return; 403f21c7bc5SThomas Graf errout: 404f21c7bc5SThomas Graf if (err < 0) 4054d1169c1SDenis V. Lunev rtnl_set_sk_err(info->nl_net, RTNLGRP_IPV4_ROUTE, err); 4061da177e4SLinus Torvalds } 4071da177e4SLinus Torvalds 4081da177e4SLinus Torvalds /* Return the first fib alias matching TOS with 4091da177e4SLinus Torvalds * priority less than or equal to PRIO. 4101da177e4SLinus Torvalds */ 4111da177e4SLinus Torvalds struct fib_alias *fib_find_alias(struct list_head *fah, u8 tos, u32 prio) 4121da177e4SLinus Torvalds { 4131da177e4SLinus Torvalds if (fah) { 4141da177e4SLinus Torvalds struct fib_alias *fa; 4151da177e4SLinus Torvalds list_for_each_entry(fa, fah, fa_list) { 4161da177e4SLinus Torvalds if (fa->fa_tos > tos) 4171da177e4SLinus Torvalds continue; 4181da177e4SLinus Torvalds if (fa->fa_info->fib_priority >= prio || 4191da177e4SLinus Torvalds fa->fa_tos < tos) 4201da177e4SLinus Torvalds return fa; 4211da177e4SLinus Torvalds } 4221da177e4SLinus Torvalds } 4231da177e4SLinus Torvalds return NULL; 4241da177e4SLinus Torvalds } 4251da177e4SLinus Torvalds 4261da177e4SLinus Torvalds int fib_detect_death(struct fib_info *fi, int order, 427c17860a0SDenis V. Lunev struct fib_info **last_resort, int *last_idx, int dflt) 4281da177e4SLinus Torvalds { 4291da177e4SLinus Torvalds struct neighbour *n; 4301da177e4SLinus Torvalds int state = NUD_NONE; 4311da177e4SLinus Torvalds 4321da177e4SLinus Torvalds n = neigh_lookup(&arp_tbl, &fi->fib_nh[0].nh_gw, fi->fib_dev); 4331da177e4SLinus Torvalds if (n) { 4341da177e4SLinus Torvalds state = n->nud_state; 4351da177e4SLinus Torvalds neigh_release(n); 4361da177e4SLinus Torvalds } 4371da177e4SLinus Torvalds if (state == NUD_REACHABLE) 4381da177e4SLinus Torvalds return 0; 439c17860a0SDenis V. Lunev if ((state & NUD_VALID) && order != dflt) 4401da177e4SLinus Torvalds return 0; 4411da177e4SLinus Torvalds if ((state & NUD_VALID) || 442c17860a0SDenis V. Lunev (*last_idx < 0 && order > dflt)) { 4431da177e4SLinus Torvalds *last_resort = fi; 4441da177e4SLinus Torvalds *last_idx = order; 4451da177e4SLinus Torvalds } 4461da177e4SLinus Torvalds return 1; 4471da177e4SLinus Torvalds } 4481da177e4SLinus Torvalds 4491da177e4SLinus Torvalds #ifdef CONFIG_IP_ROUTE_MULTIPATH 4501da177e4SLinus Torvalds 4514e902c57SThomas Graf static int fib_count_nexthops(struct rtnexthop *rtnh, int remaining) 4521da177e4SLinus Torvalds { 4531da177e4SLinus Torvalds int nhs = 0; 4541da177e4SLinus Torvalds 4554e902c57SThomas Graf while (rtnh_ok(rtnh, remaining)) { 4561da177e4SLinus Torvalds nhs++; 4574e902c57SThomas Graf rtnh = rtnh_next(rtnh, &remaining); 4581da177e4SLinus Torvalds } 4591da177e4SLinus Torvalds 4604e902c57SThomas Graf /* leftover implies invalid nexthop configuration, discard it */ 4614e902c57SThomas Graf return remaining > 0 ? 0 : nhs; 4624e902c57SThomas Graf } 4631da177e4SLinus Torvalds 4644e902c57SThomas Graf static int fib_get_nhs(struct fib_info *fi, struct rtnexthop *rtnh, 4654e902c57SThomas Graf int remaining, struct fib_config *cfg) 4664e902c57SThomas Graf { 4671da177e4SLinus Torvalds change_nexthops(fi) { 4684e902c57SThomas Graf int attrlen; 4694e902c57SThomas Graf 4704e902c57SThomas Graf if (!rtnh_ok(rtnh, remaining)) 4711da177e4SLinus Torvalds return -EINVAL; 4724e902c57SThomas Graf 47371fceff0SDavid S. Miller nexthop_nh->nh_flags = 47471fceff0SDavid S. Miller (cfg->fc_flags & ~0xFF) | rtnh->rtnh_flags; 47571fceff0SDavid S. Miller nexthop_nh->nh_oif = rtnh->rtnh_ifindex; 47671fceff0SDavid S. Miller nexthop_nh->nh_weight = rtnh->rtnh_hops + 1; 4774e902c57SThomas Graf 4784e902c57SThomas Graf attrlen = rtnh_attrlen(rtnh); 4794e902c57SThomas Graf if (attrlen > 0) { 4804e902c57SThomas Graf struct nlattr *nla, *attrs = rtnh_attrs(rtnh); 4814e902c57SThomas Graf 4824e902c57SThomas Graf nla = nla_find(attrs, attrlen, RTA_GATEWAY); 48371fceff0SDavid S. Miller nexthop_nh->nh_gw = nla ? nla_get_be32(nla) : 0; 484c7066f70SPatrick McHardy #ifdef CONFIG_IP_ROUTE_CLASSID 4854e902c57SThomas Graf nla = nla_find(attrs, attrlen, RTA_FLOW); 48671fceff0SDavid S. Miller nexthop_nh->nh_tclassid = nla ? nla_get_u32(nla) : 0; 4877a9bc9b8SDavid S. Miller if (nexthop_nh->nh_tclassid) 488f4530fa5SDavid S. Miller fi->fib_net->ipv4.fib_num_tclassid_users++; 4891da177e4SLinus Torvalds #endif 4901da177e4SLinus Torvalds } 4914e902c57SThomas Graf 4924e902c57SThomas Graf rtnh = rtnh_next(rtnh, &remaining); 4931da177e4SLinus Torvalds } endfor_nexthops(fi); 4944e902c57SThomas Graf 4951da177e4SLinus Torvalds return 0; 4961da177e4SLinus Torvalds } 4971da177e4SLinus Torvalds 4981da177e4SLinus Torvalds #endif 4991da177e4SLinus Torvalds 5004e902c57SThomas Graf int fib_nh_match(struct fib_config *cfg, struct fib_info *fi) 5011da177e4SLinus Torvalds { 5021da177e4SLinus Torvalds #ifdef CONFIG_IP_ROUTE_MULTIPATH 5034e902c57SThomas Graf struct rtnexthop *rtnh; 5044e902c57SThomas Graf int remaining; 5051da177e4SLinus Torvalds #endif 5061da177e4SLinus Torvalds 5074e902c57SThomas Graf if (cfg->fc_priority && cfg->fc_priority != fi->fib_priority) 5081da177e4SLinus Torvalds return 1; 5091da177e4SLinus Torvalds 5104e902c57SThomas Graf if (cfg->fc_oif || cfg->fc_gw) { 5114e902c57SThomas Graf if ((!cfg->fc_oif || cfg->fc_oif == fi->fib_nh->nh_oif) && 5124e902c57SThomas Graf (!cfg->fc_gw || cfg->fc_gw == fi->fib_nh->nh_gw)) 5131da177e4SLinus Torvalds return 0; 5141da177e4SLinus Torvalds return 1; 5151da177e4SLinus Torvalds } 5161da177e4SLinus Torvalds 5171da177e4SLinus Torvalds #ifdef CONFIG_IP_ROUTE_MULTIPATH 5184e902c57SThomas Graf if (cfg->fc_mp == NULL) 5191da177e4SLinus Torvalds return 0; 5204e902c57SThomas Graf 5214e902c57SThomas Graf rtnh = cfg->fc_mp; 5224e902c57SThomas Graf remaining = cfg->fc_mp_len; 5231da177e4SLinus Torvalds 5241da177e4SLinus Torvalds for_nexthops(fi) { 5254e902c57SThomas Graf int attrlen; 5261da177e4SLinus Torvalds 5274e902c57SThomas Graf if (!rtnh_ok(rtnh, remaining)) 5281da177e4SLinus Torvalds return -EINVAL; 5294e902c57SThomas Graf 5304e902c57SThomas Graf if (rtnh->rtnh_ifindex && rtnh->rtnh_ifindex != nh->nh_oif) 5311da177e4SLinus Torvalds return 1; 5324e902c57SThomas Graf 5334e902c57SThomas Graf attrlen = rtnh_attrlen(rtnh); 5344e902c57SThomas Graf if (attrlen < 0) { 5354e902c57SThomas Graf struct nlattr *nla, *attrs = rtnh_attrs(rtnh); 5364e902c57SThomas Graf 5374e902c57SThomas Graf nla = nla_find(attrs, attrlen, RTA_GATEWAY); 53817fb2c64SAl Viro if (nla && nla_get_be32(nla) != nh->nh_gw) 5391da177e4SLinus Torvalds return 1; 540c7066f70SPatrick McHardy #ifdef CONFIG_IP_ROUTE_CLASSID 5414e902c57SThomas Graf nla = nla_find(attrs, attrlen, RTA_FLOW); 5424e902c57SThomas Graf if (nla && nla_get_u32(nla) != nh->nh_tclassid) 5431da177e4SLinus Torvalds return 1; 5441da177e4SLinus Torvalds #endif 5451da177e4SLinus Torvalds } 5464e902c57SThomas Graf 5474e902c57SThomas Graf rtnh = rtnh_next(rtnh, &remaining); 5481da177e4SLinus Torvalds } endfor_nexthops(fi); 5491da177e4SLinus Torvalds #endif 5501da177e4SLinus Torvalds return 0; 5511da177e4SLinus Torvalds } 5521da177e4SLinus Torvalds 5531da177e4SLinus Torvalds 5541da177e4SLinus Torvalds /* 5556a31d2a9SEric Dumazet * Picture 5566a31d2a9SEric Dumazet * ------- 5576a31d2a9SEric Dumazet * 5586a31d2a9SEric Dumazet * Semantics of nexthop is very messy by historical reasons. 5596a31d2a9SEric Dumazet * We have to take into account, that: 5606a31d2a9SEric Dumazet * a) gateway can be actually local interface address, 5616a31d2a9SEric Dumazet * so that gatewayed route is direct. 5626a31d2a9SEric Dumazet * b) gateway must be on-link address, possibly 5636a31d2a9SEric Dumazet * described not by an ifaddr, but also by a direct route. 5646a31d2a9SEric Dumazet * c) If both gateway and interface are specified, they should not 5656a31d2a9SEric Dumazet * contradict. 5666a31d2a9SEric Dumazet * d) If we use tunnel routes, gateway could be not on-link. 5676a31d2a9SEric Dumazet * 5686a31d2a9SEric Dumazet * Attempt to reconcile all of these (alas, self-contradictory) conditions 5696a31d2a9SEric Dumazet * results in pretty ugly and hairy code with obscure logic. 5706a31d2a9SEric Dumazet * 5716a31d2a9SEric Dumazet * I chose to generalized it instead, so that the size 5726a31d2a9SEric Dumazet * of code does not increase practically, but it becomes 5736a31d2a9SEric Dumazet * much more general. 5746a31d2a9SEric Dumazet * Every prefix is assigned a "scope" value: "host" is local address, 5756a31d2a9SEric Dumazet * "link" is direct route, 5766a31d2a9SEric Dumazet * [ ... "site" ... "interior" ... ] 5776a31d2a9SEric Dumazet * and "universe" is true gateway route with global meaning. 5786a31d2a9SEric Dumazet * 5796a31d2a9SEric Dumazet * Every prefix refers to a set of "nexthop"s (gw, oif), 5806a31d2a9SEric Dumazet * where gw must have narrower scope. This recursion stops 5816a31d2a9SEric Dumazet * when gw has LOCAL scope or if "nexthop" is declared ONLINK, 5826a31d2a9SEric Dumazet * which means that gw is forced to be on link. 5836a31d2a9SEric Dumazet * 5846a31d2a9SEric Dumazet * Code is still hairy, but now it is apparently logically 5856a31d2a9SEric Dumazet * consistent and very flexible. F.e. as by-product it allows 5866a31d2a9SEric Dumazet * to co-exists in peace independent exterior and interior 5876a31d2a9SEric Dumazet * routing processes. 5886a31d2a9SEric Dumazet * 5896a31d2a9SEric Dumazet * Normally it looks as following. 5906a31d2a9SEric Dumazet * 5916a31d2a9SEric Dumazet * {universe prefix} -> (gw, oif) [scope link] 5926a31d2a9SEric Dumazet * | 5936a31d2a9SEric Dumazet * |-> {link prefix} -> (gw, oif) [scope local] 5946a31d2a9SEric Dumazet * | 5956a31d2a9SEric Dumazet * |-> {local prefix} (terminal node) 5961da177e4SLinus Torvalds */ 5974e902c57SThomas Graf static int fib_check_nh(struct fib_config *cfg, struct fib_info *fi, 5984e902c57SThomas Graf struct fib_nh *nh) 5991da177e4SLinus Torvalds { 6001da177e4SLinus Torvalds int err; 60186167a37SDenis V. Lunev struct net *net; 6026a31d2a9SEric Dumazet struct net_device *dev; 6031da177e4SLinus Torvalds 60486167a37SDenis V. Lunev net = cfg->fc_nlinfo.nl_net; 6051da177e4SLinus Torvalds if (nh->nh_gw) { 6061da177e4SLinus Torvalds struct fib_result res; 6071da177e4SLinus Torvalds 6081da177e4SLinus Torvalds if (nh->nh_flags & RTNH_F_ONLINK) { 6091da177e4SLinus Torvalds 6104e902c57SThomas Graf if (cfg->fc_scope >= RT_SCOPE_LINK) 6111da177e4SLinus Torvalds return -EINVAL; 61286167a37SDenis V. Lunev if (inet_addr_type(net, nh->nh_gw) != RTN_UNICAST) 6131da177e4SLinus Torvalds return -EINVAL; 6146a31d2a9SEric Dumazet dev = __dev_get_by_index(net, nh->nh_oif); 6156a31d2a9SEric Dumazet if (!dev) 6161da177e4SLinus Torvalds return -ENODEV; 6171da177e4SLinus Torvalds if (!(dev->flags & IFF_UP)) 6181da177e4SLinus Torvalds return -ENETDOWN; 6191da177e4SLinus Torvalds nh->nh_dev = dev; 6201da177e4SLinus Torvalds dev_hold(dev); 6211da177e4SLinus Torvalds nh->nh_scope = RT_SCOPE_LINK; 6221da177e4SLinus Torvalds return 0; 6231da177e4SLinus Torvalds } 624ebc0ffaeSEric Dumazet rcu_read_lock(); 6251da177e4SLinus Torvalds { 6269ade2286SDavid S. Miller struct flowi4 fl4 = { 6279ade2286SDavid S. Miller .daddr = nh->nh_gw, 6289ade2286SDavid S. Miller .flowi4_scope = cfg->fc_scope + 1, 6299ade2286SDavid S. Miller .flowi4_oif = nh->nh_oif, 6304e902c57SThomas Graf }; 6311da177e4SLinus Torvalds 6321da177e4SLinus Torvalds /* It is not necessary, but requires a bit of thinking */ 6339ade2286SDavid S. Miller if (fl4.flowi4_scope < RT_SCOPE_LINK) 6349ade2286SDavid S. Miller fl4.flowi4_scope = RT_SCOPE_LINK; 6359ade2286SDavid S. Miller err = fib_lookup(net, &fl4, &res); 636ebc0ffaeSEric Dumazet if (err) { 637ebc0ffaeSEric Dumazet rcu_read_unlock(); 6381da177e4SLinus Torvalds return err; 6391da177e4SLinus Torvalds } 640ebc0ffaeSEric Dumazet } 6411da177e4SLinus Torvalds err = -EINVAL; 6421da177e4SLinus Torvalds if (res.type != RTN_UNICAST && res.type != RTN_LOCAL) 6431da177e4SLinus Torvalds goto out; 6441da177e4SLinus Torvalds nh->nh_scope = res.scope; 6451da177e4SLinus Torvalds nh->nh_oif = FIB_RES_OIF(res); 6466a31d2a9SEric Dumazet nh->nh_dev = dev = FIB_RES_DEV(res); 6476a31d2a9SEric Dumazet if (!dev) 6481da177e4SLinus Torvalds goto out; 6496a31d2a9SEric Dumazet dev_hold(dev); 6508723e1b4SEric Dumazet err = (dev->flags & IFF_UP) ? 0 : -ENETDOWN; 6511da177e4SLinus Torvalds } else { 6521da177e4SLinus Torvalds struct in_device *in_dev; 6531da177e4SLinus Torvalds 6541da177e4SLinus Torvalds if (nh->nh_flags & (RTNH_F_PERVASIVE | RTNH_F_ONLINK)) 6551da177e4SLinus Torvalds return -EINVAL; 6561da177e4SLinus Torvalds 6578723e1b4SEric Dumazet rcu_read_lock(); 6588723e1b4SEric Dumazet err = -ENODEV; 65986167a37SDenis V. Lunev in_dev = inetdev_by_index(net, nh->nh_oif); 6601da177e4SLinus Torvalds if (in_dev == NULL) 6618723e1b4SEric Dumazet goto out; 6628723e1b4SEric Dumazet err = -ENETDOWN; 6638723e1b4SEric Dumazet if (!(in_dev->dev->flags & IFF_UP)) 6648723e1b4SEric Dumazet goto out; 6651da177e4SLinus Torvalds nh->nh_dev = in_dev->dev; 6661da177e4SLinus Torvalds dev_hold(nh->nh_dev); 6671da177e4SLinus Torvalds nh->nh_scope = RT_SCOPE_HOST; 6688723e1b4SEric Dumazet err = 0; 6691da177e4SLinus Torvalds } 6708723e1b4SEric Dumazet out: 6718723e1b4SEric Dumazet rcu_read_unlock(); 6728723e1b4SEric Dumazet return err; 6731da177e4SLinus Torvalds } 6741da177e4SLinus Torvalds 67581f7bf6cSAl Viro static inline unsigned int fib_laddr_hashfn(__be32 val) 6761da177e4SLinus Torvalds { 677123b9731SDavid S. Miller unsigned int mask = (fib_info_hash_size - 1); 6781da177e4SLinus Torvalds 6796a31d2a9SEric Dumazet return ((__force u32)val ^ 6806a31d2a9SEric Dumazet ((__force u32)val >> 7) ^ 6816a31d2a9SEric Dumazet ((__force u32)val >> 14)) & mask; 6821da177e4SLinus Torvalds } 6831da177e4SLinus Torvalds 684123b9731SDavid S. Miller static struct hlist_head *fib_info_hash_alloc(int bytes) 6851da177e4SLinus Torvalds { 6861da177e4SLinus Torvalds if (bytes <= PAGE_SIZE) 68788f83491SJoonwoo Park return kzalloc(bytes, GFP_KERNEL); 6881da177e4SLinus Torvalds else 6891da177e4SLinus Torvalds return (struct hlist_head *) 6906a31d2a9SEric Dumazet __get_free_pages(GFP_KERNEL | __GFP_ZERO, 6916a31d2a9SEric Dumazet get_order(bytes)); 6921da177e4SLinus Torvalds } 6931da177e4SLinus Torvalds 694123b9731SDavid S. Miller static void fib_info_hash_free(struct hlist_head *hash, int bytes) 6951da177e4SLinus Torvalds { 6961da177e4SLinus Torvalds if (!hash) 6971da177e4SLinus Torvalds return; 6981da177e4SLinus Torvalds 6991da177e4SLinus Torvalds if (bytes <= PAGE_SIZE) 7001da177e4SLinus Torvalds kfree(hash); 7011da177e4SLinus Torvalds else 7021da177e4SLinus Torvalds free_pages((unsigned long) hash, get_order(bytes)); 7031da177e4SLinus Torvalds } 7041da177e4SLinus Torvalds 705123b9731SDavid S. Miller static void fib_info_hash_move(struct hlist_head *new_info_hash, 7061da177e4SLinus Torvalds struct hlist_head *new_laddrhash, 7071da177e4SLinus Torvalds unsigned int new_size) 7081da177e4SLinus Torvalds { 709b7656e7fSDavid S. Miller struct hlist_head *old_info_hash, *old_laddrhash; 710123b9731SDavid S. Miller unsigned int old_size = fib_info_hash_size; 711b7656e7fSDavid S. Miller unsigned int i, bytes; 7121da177e4SLinus Torvalds 713832b4c5eSStephen Hemminger spin_lock_bh(&fib_info_lock); 714b7656e7fSDavid S. Miller old_info_hash = fib_info_hash; 715b7656e7fSDavid S. Miller old_laddrhash = fib_info_laddrhash; 716123b9731SDavid S. Miller fib_info_hash_size = new_size; 7171da177e4SLinus Torvalds 7181da177e4SLinus Torvalds for (i = 0; i < old_size; i++) { 7191da177e4SLinus Torvalds struct hlist_head *head = &fib_info_hash[i]; 7201da177e4SLinus Torvalds struct hlist_node *node, *n; 7211da177e4SLinus Torvalds struct fib_info *fi; 7221da177e4SLinus Torvalds 7231da177e4SLinus Torvalds hlist_for_each_entry_safe(fi, node, n, head, fib_hash) { 7241da177e4SLinus Torvalds struct hlist_head *dest; 7251da177e4SLinus Torvalds unsigned int new_hash; 7261da177e4SLinus Torvalds 7271da177e4SLinus Torvalds hlist_del(&fi->fib_hash); 7281da177e4SLinus Torvalds 7291da177e4SLinus Torvalds new_hash = fib_info_hashfn(fi); 7301da177e4SLinus Torvalds dest = &new_info_hash[new_hash]; 7311da177e4SLinus Torvalds hlist_add_head(&fi->fib_hash, dest); 7321da177e4SLinus Torvalds } 7331da177e4SLinus Torvalds } 7341da177e4SLinus Torvalds fib_info_hash = new_info_hash; 7351da177e4SLinus Torvalds 7361da177e4SLinus Torvalds for (i = 0; i < old_size; i++) { 7371da177e4SLinus Torvalds struct hlist_head *lhead = &fib_info_laddrhash[i]; 7381da177e4SLinus Torvalds struct hlist_node *node, *n; 7391da177e4SLinus Torvalds struct fib_info *fi; 7401da177e4SLinus Torvalds 7411da177e4SLinus Torvalds hlist_for_each_entry_safe(fi, node, n, lhead, fib_lhash) { 7421da177e4SLinus Torvalds struct hlist_head *ldest; 7431da177e4SLinus Torvalds unsigned int new_hash; 7441da177e4SLinus Torvalds 7451da177e4SLinus Torvalds hlist_del(&fi->fib_lhash); 7461da177e4SLinus Torvalds 7471da177e4SLinus Torvalds new_hash = fib_laddr_hashfn(fi->fib_prefsrc); 7481da177e4SLinus Torvalds ldest = &new_laddrhash[new_hash]; 7491da177e4SLinus Torvalds hlist_add_head(&fi->fib_lhash, ldest); 7501da177e4SLinus Torvalds } 7511da177e4SLinus Torvalds } 7521da177e4SLinus Torvalds fib_info_laddrhash = new_laddrhash; 7531da177e4SLinus Torvalds 754832b4c5eSStephen Hemminger spin_unlock_bh(&fib_info_lock); 755b7656e7fSDavid S. Miller 756b7656e7fSDavid S. Miller bytes = old_size * sizeof(struct hlist_head *); 757123b9731SDavid S. Miller fib_info_hash_free(old_info_hash, bytes); 758123b9731SDavid S. Miller fib_info_hash_free(old_laddrhash, bytes); 7591da177e4SLinus Torvalds } 7601da177e4SLinus Torvalds 761436c3b66SDavid S. Miller __be32 fib_info_update_nh_saddr(struct net *net, struct fib_nh *nh) 762436c3b66SDavid S. Miller { 763436c3b66SDavid S. Miller nh->nh_saddr = inet_select_addr(nh->nh_dev, 764436c3b66SDavid S. Miller nh->nh_gw, 76537e826c5SDavid S. Miller nh->nh_parent->fib_scope); 766436c3b66SDavid S. Miller nh->nh_saddr_genid = atomic_read(&net->ipv4.dev_addr_genid); 767436c3b66SDavid S. Miller 768436c3b66SDavid S. Miller return nh->nh_saddr; 769436c3b66SDavid S. Miller } 770436c3b66SDavid S. Miller 7714e902c57SThomas Graf struct fib_info *fib_create_info(struct fib_config *cfg) 7721da177e4SLinus Torvalds { 7731da177e4SLinus Torvalds int err; 7741da177e4SLinus Torvalds struct fib_info *fi = NULL; 7751da177e4SLinus Torvalds struct fib_info *ofi; 7761da177e4SLinus Torvalds int nhs = 1; 7777462bd74SDenis V. Lunev struct net *net = cfg->fc_nlinfo.nl_net; 7781da177e4SLinus Torvalds 7794c8237cdSDavid S. Miller if (cfg->fc_type > RTN_MAX) 7804c8237cdSDavid S. Miller goto err_inval; 7814c8237cdSDavid S. Miller 7821da177e4SLinus Torvalds /* Fast check to catch the most weird cases */ 7834e902c57SThomas Graf if (fib_props[cfg->fc_type].scope > cfg->fc_scope) 7841da177e4SLinus Torvalds goto err_inval; 7851da177e4SLinus Torvalds 7861da177e4SLinus Torvalds #ifdef CONFIG_IP_ROUTE_MULTIPATH 7874e902c57SThomas Graf if (cfg->fc_mp) { 7884e902c57SThomas Graf nhs = fib_count_nexthops(cfg->fc_mp, cfg->fc_mp_len); 7891da177e4SLinus Torvalds if (nhs == 0) 7901da177e4SLinus Torvalds goto err_inval; 7911da177e4SLinus Torvalds } 7921da177e4SLinus Torvalds #endif 7931da177e4SLinus Torvalds 7941da177e4SLinus Torvalds err = -ENOBUFS; 795123b9731SDavid S. Miller if (fib_info_cnt >= fib_info_hash_size) { 796123b9731SDavid S. Miller unsigned int new_size = fib_info_hash_size << 1; 7971da177e4SLinus Torvalds struct hlist_head *new_info_hash; 7981da177e4SLinus Torvalds struct hlist_head *new_laddrhash; 7991da177e4SLinus Torvalds unsigned int bytes; 8001da177e4SLinus Torvalds 8011da177e4SLinus Torvalds if (!new_size) 8021da177e4SLinus Torvalds new_size = 1; 8031da177e4SLinus Torvalds bytes = new_size * sizeof(struct hlist_head *); 804123b9731SDavid S. Miller new_info_hash = fib_info_hash_alloc(bytes); 805123b9731SDavid S. Miller new_laddrhash = fib_info_hash_alloc(bytes); 8061da177e4SLinus Torvalds if (!new_info_hash || !new_laddrhash) { 807123b9731SDavid S. Miller fib_info_hash_free(new_info_hash, bytes); 808123b9731SDavid S. Miller fib_info_hash_free(new_laddrhash, bytes); 80988f83491SJoonwoo Park } else 810123b9731SDavid S. Miller fib_info_hash_move(new_info_hash, new_laddrhash, new_size); 8111da177e4SLinus Torvalds 812123b9731SDavid S. Miller if (!fib_info_hash_size) 8131da177e4SLinus Torvalds goto failure; 8141da177e4SLinus Torvalds } 8151da177e4SLinus Torvalds 8160da974f4SPanagiotis Issaris fi = kzalloc(sizeof(*fi)+nhs*sizeof(struct fib_nh), GFP_KERNEL); 8171da177e4SLinus Torvalds if (fi == NULL) 8181da177e4SLinus Torvalds goto failure; 819725d1e1bSDavid S. Miller if (cfg->fc_mx) { 8209c150e82SDavid S. Miller fi->fib_metrics = kzalloc(sizeof(u32) * RTAX_MAX, GFP_KERNEL); 8219c150e82SDavid S. Miller if (!fi->fib_metrics) 8229c150e82SDavid S. Miller goto failure; 823725d1e1bSDavid S. Miller } else 824725d1e1bSDavid S. Miller fi->fib_metrics = (u32 *) dst_default_metrics; 8251da177e4SLinus Torvalds fib_info_cnt++; 8261da177e4SLinus Torvalds 82757d7a600SDenis V. Lunev fi->fib_net = hold_net(net); 8284e902c57SThomas Graf fi->fib_protocol = cfg->fc_protocol; 82937e826c5SDavid S. Miller fi->fib_scope = cfg->fc_scope; 8304e902c57SThomas Graf fi->fib_flags = cfg->fc_flags; 8314e902c57SThomas Graf fi->fib_priority = cfg->fc_priority; 8324e902c57SThomas Graf fi->fib_prefsrc = cfg->fc_prefsrc; 8331da177e4SLinus Torvalds 8341da177e4SLinus Torvalds fi->fib_nhs = nhs; 8351da177e4SLinus Torvalds change_nexthops(fi) { 83671fceff0SDavid S. Miller nexthop_nh->nh_parent = fi; 837*d26b3a7cSEric Dumazet nexthop_nh->nh_pcpu_rth_output = alloc_percpu(struct rtable __rcu *); 8381da177e4SLinus Torvalds } endfor_nexthops(fi) 8391da177e4SLinus Torvalds 8404e902c57SThomas Graf if (cfg->fc_mx) { 8414e902c57SThomas Graf struct nlattr *nla; 8424e902c57SThomas Graf int remaining; 8431da177e4SLinus Torvalds 8444e902c57SThomas Graf nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) { 8458f4c1f9bSThomas Graf int type = nla_type(nla); 8464e902c57SThomas Graf 8474e902c57SThomas Graf if (type) { 8486fac2625SDavid S. Miller u32 val; 8496fac2625SDavid S. Miller 8504e902c57SThomas Graf if (type > RTAX_MAX) 8511da177e4SLinus Torvalds goto err_inval; 8526fac2625SDavid S. Miller val = nla_get_u32(nla); 8536fac2625SDavid S. Miller if (type == RTAX_ADVMSS && val > 65535 - 40) 8546fac2625SDavid S. Miller val = 65535 - 40; 855710ab6c0SDavid S. Miller if (type == RTAX_MTU && val > 65535 - 15) 856710ab6c0SDavid S. Miller val = 65535 - 15; 8576fac2625SDavid S. Miller fi->fib_metrics[type - 1] = val; 8581da177e4SLinus Torvalds } 8591da177e4SLinus Torvalds } 8604e902c57SThomas Graf } 8611da177e4SLinus Torvalds 8624e902c57SThomas Graf if (cfg->fc_mp) { 8631da177e4SLinus Torvalds #ifdef CONFIG_IP_ROUTE_MULTIPATH 8644e902c57SThomas Graf err = fib_get_nhs(fi, cfg->fc_mp, cfg->fc_mp_len, cfg); 8654e902c57SThomas Graf if (err != 0) 8661da177e4SLinus Torvalds goto failure; 8674e902c57SThomas Graf if (cfg->fc_oif && fi->fib_nh->nh_oif != cfg->fc_oif) 8681da177e4SLinus Torvalds goto err_inval; 8694e902c57SThomas Graf if (cfg->fc_gw && fi->fib_nh->nh_gw != cfg->fc_gw) 8701da177e4SLinus Torvalds goto err_inval; 871c7066f70SPatrick McHardy #ifdef CONFIG_IP_ROUTE_CLASSID 8724e902c57SThomas Graf if (cfg->fc_flow && fi->fib_nh->nh_tclassid != cfg->fc_flow) 8731da177e4SLinus Torvalds goto err_inval; 8741da177e4SLinus Torvalds #endif 8751da177e4SLinus Torvalds #else 8761da177e4SLinus Torvalds goto err_inval; 8771da177e4SLinus Torvalds #endif 8781da177e4SLinus Torvalds } else { 8791da177e4SLinus Torvalds struct fib_nh *nh = fi->fib_nh; 8804e902c57SThomas Graf 8814e902c57SThomas Graf nh->nh_oif = cfg->fc_oif; 8824e902c57SThomas Graf nh->nh_gw = cfg->fc_gw; 8834e902c57SThomas Graf nh->nh_flags = cfg->fc_flags; 884c7066f70SPatrick McHardy #ifdef CONFIG_IP_ROUTE_CLASSID 8854e902c57SThomas Graf nh->nh_tclassid = cfg->fc_flow; 8867a9bc9b8SDavid S. Miller if (nh->nh_tclassid) 887f4530fa5SDavid S. Miller fi->fib_net->ipv4.fib_num_tclassid_users++; 8881da177e4SLinus Torvalds #endif 8891da177e4SLinus Torvalds #ifdef CONFIG_IP_ROUTE_MULTIPATH 8901da177e4SLinus Torvalds nh->nh_weight = 1; 8911da177e4SLinus Torvalds #endif 8921da177e4SLinus Torvalds } 8931da177e4SLinus Torvalds 8944e902c57SThomas Graf if (fib_props[cfg->fc_type].error) { 8954e902c57SThomas Graf if (cfg->fc_gw || cfg->fc_oif || cfg->fc_mp) 8961da177e4SLinus Torvalds goto err_inval; 8971da177e4SLinus Torvalds goto link_it; 8984c8237cdSDavid S. Miller } else { 8994c8237cdSDavid S. Miller switch (cfg->fc_type) { 9004c8237cdSDavid S. Miller case RTN_UNICAST: 9014c8237cdSDavid S. Miller case RTN_LOCAL: 9024c8237cdSDavid S. Miller case RTN_BROADCAST: 9034c8237cdSDavid S. Miller case RTN_ANYCAST: 9044c8237cdSDavid S. Miller case RTN_MULTICAST: 9054c8237cdSDavid S. Miller break; 9064c8237cdSDavid S. Miller default: 9074c8237cdSDavid S. Miller goto err_inval; 9084c8237cdSDavid S. Miller } 9091da177e4SLinus Torvalds } 9101da177e4SLinus Torvalds 9114e902c57SThomas Graf if (cfg->fc_scope > RT_SCOPE_HOST) 9121da177e4SLinus Torvalds goto err_inval; 9131da177e4SLinus Torvalds 9144e902c57SThomas Graf if (cfg->fc_scope == RT_SCOPE_HOST) { 9151da177e4SLinus Torvalds struct fib_nh *nh = fi->fib_nh; 9161da177e4SLinus Torvalds 9171da177e4SLinus Torvalds /* Local address is added. */ 9181da177e4SLinus Torvalds if (nhs != 1 || nh->nh_gw) 9191da177e4SLinus Torvalds goto err_inval; 9201da177e4SLinus Torvalds nh->nh_scope = RT_SCOPE_NOWHERE; 9217462bd74SDenis V. Lunev nh->nh_dev = dev_get_by_index(net, fi->fib_nh->nh_oif); 9221da177e4SLinus Torvalds err = -ENODEV; 9231da177e4SLinus Torvalds if (nh->nh_dev == NULL) 9241da177e4SLinus Torvalds goto failure; 9251da177e4SLinus Torvalds } else { 9261da177e4SLinus Torvalds change_nexthops(fi) { 9276a31d2a9SEric Dumazet err = fib_check_nh(cfg, fi, nexthop_nh); 9286a31d2a9SEric Dumazet if (err != 0) 9291da177e4SLinus Torvalds goto failure; 9301da177e4SLinus Torvalds } endfor_nexthops(fi) 9311da177e4SLinus Torvalds } 9321da177e4SLinus Torvalds 9331da177e4SLinus Torvalds if (fi->fib_prefsrc) { 9344e902c57SThomas Graf if (cfg->fc_type != RTN_LOCAL || !cfg->fc_dst || 9354e902c57SThomas Graf fi->fib_prefsrc != cfg->fc_dst) 9367462bd74SDenis V. Lunev if (inet_addr_type(net, fi->fib_prefsrc) != RTN_LOCAL) 9371da177e4SLinus Torvalds goto err_inval; 9381da177e4SLinus Torvalds } 9391da177e4SLinus Torvalds 9401fc050a1SDavid S. Miller change_nexthops(fi) { 941436c3b66SDavid S. Miller fib_info_update_nh_saddr(net, nexthop_nh); 9421fc050a1SDavid S. Miller } endfor_nexthops(fi) 9431fc050a1SDavid S. Miller 9441da177e4SLinus Torvalds link_it: 9456a31d2a9SEric Dumazet ofi = fib_find_info(fi); 9466a31d2a9SEric Dumazet if (ofi) { 9471da177e4SLinus Torvalds fi->fib_dead = 1; 9481da177e4SLinus Torvalds free_fib_info(fi); 9491da177e4SLinus Torvalds ofi->fib_treeref++; 9501da177e4SLinus Torvalds return ofi; 9511da177e4SLinus Torvalds } 9521da177e4SLinus Torvalds 9531da177e4SLinus Torvalds fi->fib_treeref++; 9541da177e4SLinus Torvalds atomic_inc(&fi->fib_clntref); 955832b4c5eSStephen Hemminger spin_lock_bh(&fib_info_lock); 9561da177e4SLinus Torvalds hlist_add_head(&fi->fib_hash, 9571da177e4SLinus Torvalds &fib_info_hash[fib_info_hashfn(fi)]); 9581da177e4SLinus Torvalds if (fi->fib_prefsrc) { 9591da177e4SLinus Torvalds struct hlist_head *head; 9601da177e4SLinus Torvalds 9611da177e4SLinus Torvalds head = &fib_info_laddrhash[fib_laddr_hashfn(fi->fib_prefsrc)]; 9621da177e4SLinus Torvalds hlist_add_head(&fi->fib_lhash, head); 9631da177e4SLinus Torvalds } 9641da177e4SLinus Torvalds change_nexthops(fi) { 9651da177e4SLinus Torvalds struct hlist_head *head; 9661da177e4SLinus Torvalds unsigned int hash; 9671da177e4SLinus Torvalds 96871fceff0SDavid S. Miller if (!nexthop_nh->nh_dev) 9691da177e4SLinus Torvalds continue; 97071fceff0SDavid S. Miller hash = fib_devindex_hashfn(nexthop_nh->nh_dev->ifindex); 9711da177e4SLinus Torvalds head = &fib_info_devhash[hash]; 97271fceff0SDavid S. Miller hlist_add_head(&nexthop_nh->nh_hash, head); 9731da177e4SLinus Torvalds } endfor_nexthops(fi) 974832b4c5eSStephen Hemminger spin_unlock_bh(&fib_info_lock); 9751da177e4SLinus Torvalds return fi; 9761da177e4SLinus Torvalds 9771da177e4SLinus Torvalds err_inval: 9781da177e4SLinus Torvalds err = -EINVAL; 9791da177e4SLinus Torvalds 9801da177e4SLinus Torvalds failure: 9811da177e4SLinus Torvalds if (fi) { 9821da177e4SLinus Torvalds fi->fib_dead = 1; 9831da177e4SLinus Torvalds free_fib_info(fi); 9841da177e4SLinus Torvalds } 9854e902c57SThomas Graf 9864e902c57SThomas Graf return ERR_PTR(err); 9871da177e4SLinus Torvalds } 9881da177e4SLinus Torvalds 989be403ea1SThomas Graf int fib_dump_info(struct sk_buff *skb, u32 pid, u32 seq, int event, 99037e826c5SDavid S. Miller u32 tb_id, u8 type, __be32 dst, int dst_len, u8 tos, 991b6544c0bSJamal Hadi Salim struct fib_info *fi, unsigned int flags) 9921da177e4SLinus Torvalds { 9931da177e4SLinus Torvalds struct nlmsghdr *nlh; 994be403ea1SThomas Graf struct rtmsg *rtm; 9951da177e4SLinus Torvalds 996be403ea1SThomas Graf nlh = nlmsg_put(skb, pid, seq, event, sizeof(*rtm), flags); 997be403ea1SThomas Graf if (nlh == NULL) 99826932566SPatrick McHardy return -EMSGSIZE; 999be403ea1SThomas Graf 1000be403ea1SThomas Graf rtm = nlmsg_data(nlh); 10011da177e4SLinus Torvalds rtm->rtm_family = AF_INET; 10021da177e4SLinus Torvalds rtm->rtm_dst_len = dst_len; 10031da177e4SLinus Torvalds rtm->rtm_src_len = 0; 10041da177e4SLinus Torvalds rtm->rtm_tos = tos; 1005709772e6SKrzysztof Piotr Oledzki if (tb_id < 256) 10061da177e4SLinus Torvalds rtm->rtm_table = tb_id; 1007709772e6SKrzysztof Piotr Oledzki else 1008709772e6SKrzysztof Piotr Oledzki rtm->rtm_table = RT_TABLE_COMPAT; 1009f3756b79SDavid S. Miller if (nla_put_u32(skb, RTA_TABLE, tb_id)) 1010f3756b79SDavid S. Miller goto nla_put_failure; 10111da177e4SLinus Torvalds rtm->rtm_type = type; 10121da177e4SLinus Torvalds rtm->rtm_flags = fi->fib_flags; 101337e826c5SDavid S. Miller rtm->rtm_scope = fi->fib_scope; 10141da177e4SLinus Torvalds rtm->rtm_protocol = fi->fib_protocol; 1015be403ea1SThomas Graf 1016f3756b79SDavid S. Miller if (rtm->rtm_dst_len && 1017f3756b79SDavid S. Miller nla_put_be32(skb, RTA_DST, dst)) 1018f3756b79SDavid S. Miller goto nla_put_failure; 1019f3756b79SDavid S. Miller if (fi->fib_priority && 1020f3756b79SDavid S. Miller nla_put_u32(skb, RTA_PRIORITY, fi->fib_priority)) 1021f3756b79SDavid S. Miller goto nla_put_failure; 10221da177e4SLinus Torvalds if (rtnetlink_put_metrics(skb, fi->fib_metrics) < 0) 1023be403ea1SThomas Graf goto nla_put_failure; 1024be403ea1SThomas Graf 1025f3756b79SDavid S. Miller if (fi->fib_prefsrc && 1026f3756b79SDavid S. Miller nla_put_be32(skb, RTA_PREFSRC, fi->fib_prefsrc)) 1027f3756b79SDavid S. Miller goto nla_put_failure; 10281da177e4SLinus Torvalds if (fi->fib_nhs == 1) { 1029f3756b79SDavid S. Miller if (fi->fib_nh->nh_gw && 1030f3756b79SDavid S. Miller nla_put_be32(skb, RTA_GATEWAY, fi->fib_nh->nh_gw)) 1031f3756b79SDavid S. Miller goto nla_put_failure; 1032f3756b79SDavid S. Miller if (fi->fib_nh->nh_oif && 1033f3756b79SDavid S. Miller nla_put_u32(skb, RTA_OIF, fi->fib_nh->nh_oif)) 1034f3756b79SDavid S. Miller goto nla_put_failure; 1035c7066f70SPatrick McHardy #ifdef CONFIG_IP_ROUTE_CLASSID 1036f3756b79SDavid S. Miller if (fi->fib_nh[0].nh_tclassid && 1037f3756b79SDavid S. Miller nla_put_u32(skb, RTA_FLOW, fi->fib_nh[0].nh_tclassid)) 1038f3756b79SDavid S. Miller goto nla_put_failure; 10398265abc0SPatrick McHardy #endif 10401da177e4SLinus Torvalds } 10411da177e4SLinus Torvalds #ifdef CONFIG_IP_ROUTE_MULTIPATH 10421da177e4SLinus Torvalds if (fi->fib_nhs > 1) { 1043be403ea1SThomas Graf struct rtnexthop *rtnh; 1044be403ea1SThomas Graf struct nlattr *mp; 1045be403ea1SThomas Graf 1046be403ea1SThomas Graf mp = nla_nest_start(skb, RTA_MULTIPATH); 1047be403ea1SThomas Graf if (mp == NULL) 1048be403ea1SThomas Graf goto nla_put_failure; 10491da177e4SLinus Torvalds 10501da177e4SLinus Torvalds for_nexthops(fi) { 1051be403ea1SThomas Graf rtnh = nla_reserve_nohdr(skb, sizeof(*rtnh)); 1052be403ea1SThomas Graf if (rtnh == NULL) 1053be403ea1SThomas Graf goto nla_put_failure; 1054be403ea1SThomas Graf 1055be403ea1SThomas Graf rtnh->rtnh_flags = nh->nh_flags & 0xFF; 1056be403ea1SThomas Graf rtnh->rtnh_hops = nh->nh_weight - 1; 1057be403ea1SThomas Graf rtnh->rtnh_ifindex = nh->nh_oif; 1058be403ea1SThomas Graf 1059f3756b79SDavid S. Miller if (nh->nh_gw && 1060f3756b79SDavid S. Miller nla_put_be32(skb, RTA_GATEWAY, nh->nh_gw)) 1061f3756b79SDavid S. Miller goto nla_put_failure; 1062c7066f70SPatrick McHardy #ifdef CONFIG_IP_ROUTE_CLASSID 1063f3756b79SDavid S. Miller if (nh->nh_tclassid && 1064f3756b79SDavid S. Miller nla_put_u32(skb, RTA_FLOW, nh->nh_tclassid)) 1065f3756b79SDavid S. Miller goto nla_put_failure; 10668265abc0SPatrick McHardy #endif 1067be403ea1SThomas Graf /* length of rtnetlink header + attributes */ 1068be403ea1SThomas Graf rtnh->rtnh_len = nlmsg_get_pos(skb) - (void *) rtnh; 10691da177e4SLinus Torvalds } endfor_nexthops(fi); 1070be403ea1SThomas Graf 1071be403ea1SThomas Graf nla_nest_end(skb, mp); 10721da177e4SLinus Torvalds } 10731da177e4SLinus Torvalds #endif 1074be403ea1SThomas Graf return nlmsg_end(skb, nlh); 10751da177e4SLinus Torvalds 1076be403ea1SThomas Graf nla_put_failure: 107726932566SPatrick McHardy nlmsg_cancel(skb, nlh); 107826932566SPatrick McHardy return -EMSGSIZE; 10791da177e4SLinus Torvalds } 10801da177e4SLinus Torvalds 10811da177e4SLinus Torvalds /* 10826a31d2a9SEric Dumazet * Update FIB if: 10836a31d2a9SEric Dumazet * - local address disappeared -> we must delete all the entries 10846a31d2a9SEric Dumazet * referring to it. 10856a31d2a9SEric Dumazet * - device went down -> we must shutdown all nexthops going via it. 10861da177e4SLinus Torvalds */ 10874814bdbdSDenis V. Lunev int fib_sync_down_addr(struct net *net, __be32 local) 10881da177e4SLinus Torvalds { 10891da177e4SLinus Torvalds int ret = 0; 10901da177e4SLinus Torvalds unsigned int hash = fib_laddr_hashfn(local); 10911da177e4SLinus Torvalds struct hlist_head *head = &fib_info_laddrhash[hash]; 10921da177e4SLinus Torvalds struct hlist_node *node; 10931da177e4SLinus Torvalds struct fib_info *fi; 10941da177e4SLinus Torvalds 109585326fa5SDenis V. Lunev if (fib_info_laddrhash == NULL || local == 0) 109685326fa5SDenis V. Lunev return 0; 109785326fa5SDenis V. Lunev 10981da177e4SLinus Torvalds hlist_for_each_entry(fi, node, head, fib_lhash) { 109909ad9bc7SOctavian Purdila if (!net_eq(fi->fib_net, net)) 11004814bdbdSDenis V. Lunev continue; 11011da177e4SLinus Torvalds if (fi->fib_prefsrc == local) { 11021da177e4SLinus Torvalds fi->fib_flags |= RTNH_F_DEAD; 11031da177e4SLinus Torvalds ret++; 11041da177e4SLinus Torvalds } 11051da177e4SLinus Torvalds } 110685326fa5SDenis V. Lunev return ret; 11071da177e4SLinus Torvalds } 11081da177e4SLinus Torvalds 110985326fa5SDenis V. Lunev int fib_sync_down_dev(struct net_device *dev, int force) 111085326fa5SDenis V. Lunev { 111185326fa5SDenis V. Lunev int ret = 0; 111285326fa5SDenis V. Lunev int scope = RT_SCOPE_NOWHERE; 11131da177e4SLinus Torvalds struct fib_info *prev_fi = NULL; 11141da177e4SLinus Torvalds unsigned int hash = fib_devindex_hashfn(dev->ifindex); 11151da177e4SLinus Torvalds struct hlist_head *head = &fib_info_devhash[hash]; 11161da177e4SLinus Torvalds struct hlist_node *node; 11171da177e4SLinus Torvalds struct fib_nh *nh; 11181da177e4SLinus Torvalds 111985326fa5SDenis V. Lunev if (force) 112085326fa5SDenis V. Lunev scope = -1; 112185326fa5SDenis V. Lunev 11221da177e4SLinus Torvalds hlist_for_each_entry(nh, node, head, nh_hash) { 11231da177e4SLinus Torvalds struct fib_info *fi = nh->nh_parent; 11241da177e4SLinus Torvalds int dead; 11251da177e4SLinus Torvalds 11261da177e4SLinus Torvalds BUG_ON(!fi->fib_nhs); 11271da177e4SLinus Torvalds if (nh->nh_dev != dev || fi == prev_fi) 11281da177e4SLinus Torvalds continue; 11291da177e4SLinus Torvalds prev_fi = fi; 11301da177e4SLinus Torvalds dead = 0; 11311da177e4SLinus Torvalds change_nexthops(fi) { 113271fceff0SDavid S. Miller if (nexthop_nh->nh_flags & RTNH_F_DEAD) 11331da177e4SLinus Torvalds dead++; 113471fceff0SDavid S. Miller else if (nexthop_nh->nh_dev == dev && 113571fceff0SDavid S. Miller nexthop_nh->nh_scope != scope) { 113671fceff0SDavid S. Miller nexthop_nh->nh_flags |= RTNH_F_DEAD; 11371da177e4SLinus Torvalds #ifdef CONFIG_IP_ROUTE_MULTIPATH 11381da177e4SLinus Torvalds spin_lock_bh(&fib_multipath_lock); 113971fceff0SDavid S. Miller fi->fib_power -= nexthop_nh->nh_power; 114071fceff0SDavid S. Miller nexthop_nh->nh_power = 0; 11411da177e4SLinus Torvalds spin_unlock_bh(&fib_multipath_lock); 11421da177e4SLinus Torvalds #endif 11431da177e4SLinus Torvalds dead++; 11441da177e4SLinus Torvalds } 11451da177e4SLinus Torvalds #ifdef CONFIG_IP_ROUTE_MULTIPATH 114671fceff0SDavid S. Miller if (force > 1 && nexthop_nh->nh_dev == dev) { 11471da177e4SLinus Torvalds dead = fi->fib_nhs; 11481da177e4SLinus Torvalds break; 11491da177e4SLinus Torvalds } 11501da177e4SLinus Torvalds #endif 11511da177e4SLinus Torvalds } endfor_nexthops(fi) 11521da177e4SLinus Torvalds if (dead == fi->fib_nhs) { 11531da177e4SLinus Torvalds fi->fib_flags |= RTNH_F_DEAD; 11541da177e4SLinus Torvalds ret++; 11551da177e4SLinus Torvalds } 11561da177e4SLinus Torvalds } 11571da177e4SLinus Torvalds 11581da177e4SLinus Torvalds return ret; 11591da177e4SLinus Torvalds } 11601da177e4SLinus Torvalds 11610c838ff1SDavid S. Miller /* Must be invoked inside of an RCU protected region. */ 11620c838ff1SDavid S. Miller void fib_select_default(struct fib_result *res) 11630c838ff1SDavid S. Miller { 11640c838ff1SDavid S. Miller struct fib_info *fi = NULL, *last_resort = NULL; 11650c838ff1SDavid S. Miller struct list_head *fa_head = res->fa_head; 11660c838ff1SDavid S. Miller struct fib_table *tb = res->table; 11670c838ff1SDavid S. Miller int order = -1, last_idx = -1; 11680c838ff1SDavid S. Miller struct fib_alias *fa; 11690c838ff1SDavid S. Miller 11700c838ff1SDavid S. Miller list_for_each_entry_rcu(fa, fa_head, fa_list) { 11710c838ff1SDavid S. Miller struct fib_info *next_fi = fa->fa_info; 11720c838ff1SDavid S. Miller 117337e826c5SDavid S. Miller if (next_fi->fib_scope != res->scope || 11740c838ff1SDavid S. Miller fa->fa_type != RTN_UNICAST) 11750c838ff1SDavid S. Miller continue; 11760c838ff1SDavid S. Miller 11770c838ff1SDavid S. Miller if (next_fi->fib_priority > res->fi->fib_priority) 11780c838ff1SDavid S. Miller break; 11790c838ff1SDavid S. Miller if (!next_fi->fib_nh[0].nh_gw || 11800c838ff1SDavid S. Miller next_fi->fib_nh[0].nh_scope != RT_SCOPE_LINK) 11810c838ff1SDavid S. Miller continue; 11820c838ff1SDavid S. Miller 11830c838ff1SDavid S. Miller fib_alias_accessed(fa); 11840c838ff1SDavid S. Miller 11850c838ff1SDavid S. Miller if (fi == NULL) { 11860c838ff1SDavid S. Miller if (next_fi != res->fi) 11870c838ff1SDavid S. Miller break; 11880c838ff1SDavid S. Miller } else if (!fib_detect_death(fi, order, &last_resort, 11890c838ff1SDavid S. Miller &last_idx, tb->tb_default)) { 11900c838ff1SDavid S. Miller fib_result_assign(res, fi); 11910c838ff1SDavid S. Miller tb->tb_default = order; 11920c838ff1SDavid S. Miller goto out; 11930c838ff1SDavid S. Miller } 11940c838ff1SDavid S. Miller fi = next_fi; 11950c838ff1SDavid S. Miller order++; 11960c838ff1SDavid S. Miller } 11970c838ff1SDavid S. Miller 11980c838ff1SDavid S. Miller if (order <= 0 || fi == NULL) { 11990c838ff1SDavid S. Miller tb->tb_default = -1; 12000c838ff1SDavid S. Miller goto out; 12010c838ff1SDavid S. Miller } 12020c838ff1SDavid S. Miller 12030c838ff1SDavid S. Miller if (!fib_detect_death(fi, order, &last_resort, &last_idx, 12040c838ff1SDavid S. Miller tb->tb_default)) { 12050c838ff1SDavid S. Miller fib_result_assign(res, fi); 12060c838ff1SDavid S. Miller tb->tb_default = order; 12070c838ff1SDavid S. Miller goto out; 12080c838ff1SDavid S. Miller } 12090c838ff1SDavid S. Miller 12100c838ff1SDavid S. Miller if (last_idx >= 0) 12110c838ff1SDavid S. Miller fib_result_assign(res, last_resort); 12120c838ff1SDavid S. Miller tb->tb_default = last_idx; 12130c838ff1SDavid S. Miller out: 121431d40937SEric Dumazet return; 12150c838ff1SDavid S. Miller } 12160c838ff1SDavid S. Miller 12171da177e4SLinus Torvalds #ifdef CONFIG_IP_ROUTE_MULTIPATH 12181da177e4SLinus Torvalds 12191da177e4SLinus Torvalds /* 12206a31d2a9SEric Dumazet * Dead device goes up. We wake up dead nexthops. 12216a31d2a9SEric Dumazet * It takes sense only on multipath routes. 12221da177e4SLinus Torvalds */ 12231da177e4SLinus Torvalds int fib_sync_up(struct net_device *dev) 12241da177e4SLinus Torvalds { 12251da177e4SLinus Torvalds struct fib_info *prev_fi; 12261da177e4SLinus Torvalds unsigned int hash; 12271da177e4SLinus Torvalds struct hlist_head *head; 12281da177e4SLinus Torvalds struct hlist_node *node; 12291da177e4SLinus Torvalds struct fib_nh *nh; 12301da177e4SLinus Torvalds int ret; 12311da177e4SLinus Torvalds 12321da177e4SLinus Torvalds if (!(dev->flags & IFF_UP)) 12331da177e4SLinus Torvalds return 0; 12341da177e4SLinus Torvalds 12351da177e4SLinus Torvalds prev_fi = NULL; 12361da177e4SLinus Torvalds hash = fib_devindex_hashfn(dev->ifindex); 12371da177e4SLinus Torvalds head = &fib_info_devhash[hash]; 12381da177e4SLinus Torvalds ret = 0; 12391da177e4SLinus Torvalds 12401da177e4SLinus Torvalds hlist_for_each_entry(nh, node, head, nh_hash) { 12411da177e4SLinus Torvalds struct fib_info *fi = nh->nh_parent; 12421da177e4SLinus Torvalds int alive; 12431da177e4SLinus Torvalds 12441da177e4SLinus Torvalds BUG_ON(!fi->fib_nhs); 12451da177e4SLinus Torvalds if (nh->nh_dev != dev || fi == prev_fi) 12461da177e4SLinus Torvalds continue; 12471da177e4SLinus Torvalds 12481da177e4SLinus Torvalds prev_fi = fi; 12491da177e4SLinus Torvalds alive = 0; 12501da177e4SLinus Torvalds change_nexthops(fi) { 125171fceff0SDavid S. Miller if (!(nexthop_nh->nh_flags & RTNH_F_DEAD)) { 12521da177e4SLinus Torvalds alive++; 12531da177e4SLinus Torvalds continue; 12541da177e4SLinus Torvalds } 125571fceff0SDavid S. Miller if (nexthop_nh->nh_dev == NULL || 125671fceff0SDavid S. Miller !(nexthop_nh->nh_dev->flags & IFF_UP)) 12571da177e4SLinus Torvalds continue; 125871fceff0SDavid S. Miller if (nexthop_nh->nh_dev != dev || 125971fceff0SDavid S. Miller !__in_dev_get_rtnl(dev)) 12601da177e4SLinus Torvalds continue; 12611da177e4SLinus Torvalds alive++; 12621da177e4SLinus Torvalds spin_lock_bh(&fib_multipath_lock); 126371fceff0SDavid S. Miller nexthop_nh->nh_power = 0; 126471fceff0SDavid S. Miller nexthop_nh->nh_flags &= ~RTNH_F_DEAD; 12651da177e4SLinus Torvalds spin_unlock_bh(&fib_multipath_lock); 12661da177e4SLinus Torvalds } endfor_nexthops(fi) 12671da177e4SLinus Torvalds 12681da177e4SLinus Torvalds if (alive > 0) { 12691da177e4SLinus Torvalds fi->fib_flags &= ~RTNH_F_DEAD; 12701da177e4SLinus Torvalds ret++; 12711da177e4SLinus Torvalds } 12721da177e4SLinus Torvalds } 12731da177e4SLinus Torvalds 12741da177e4SLinus Torvalds return ret; 12751da177e4SLinus Torvalds } 12761da177e4SLinus Torvalds 12771da177e4SLinus Torvalds /* 12786a31d2a9SEric Dumazet * The algorithm is suboptimal, but it provides really 12796a31d2a9SEric Dumazet * fair weighted route distribution. 12801da177e4SLinus Torvalds */ 12811b7fe593SDavid S. Miller void fib_select_multipath(struct fib_result *res) 12821da177e4SLinus Torvalds { 12831da177e4SLinus Torvalds struct fib_info *fi = res->fi; 12841da177e4SLinus Torvalds int w; 12851da177e4SLinus Torvalds 12861da177e4SLinus Torvalds spin_lock_bh(&fib_multipath_lock); 12871da177e4SLinus Torvalds if (fi->fib_power <= 0) { 12881da177e4SLinus Torvalds int power = 0; 12891da177e4SLinus Torvalds change_nexthops(fi) { 129071fceff0SDavid S. Miller if (!(nexthop_nh->nh_flags & RTNH_F_DEAD)) { 129171fceff0SDavid S. Miller power += nexthop_nh->nh_weight; 129271fceff0SDavid S. Miller nexthop_nh->nh_power = nexthop_nh->nh_weight; 12931da177e4SLinus Torvalds } 12941da177e4SLinus Torvalds } endfor_nexthops(fi); 12951da177e4SLinus Torvalds fi->fib_power = power; 12961da177e4SLinus Torvalds if (power <= 0) { 12971da177e4SLinus Torvalds spin_unlock_bh(&fib_multipath_lock); 12981da177e4SLinus Torvalds /* Race condition: route has just become dead. */ 12991da177e4SLinus Torvalds res->nh_sel = 0; 13001da177e4SLinus Torvalds return; 13011da177e4SLinus Torvalds } 13021da177e4SLinus Torvalds } 13031da177e4SLinus Torvalds 13041da177e4SLinus Torvalds 13051da177e4SLinus Torvalds /* w should be random number [0..fi->fib_power-1], 13066a31d2a9SEric Dumazet * it is pretty bad approximation. 13071da177e4SLinus Torvalds */ 13081da177e4SLinus Torvalds 13091da177e4SLinus Torvalds w = jiffies % fi->fib_power; 13101da177e4SLinus Torvalds 13111da177e4SLinus Torvalds change_nexthops(fi) { 131271fceff0SDavid S. Miller if (!(nexthop_nh->nh_flags & RTNH_F_DEAD) && 131371fceff0SDavid S. Miller nexthop_nh->nh_power) { 13146a31d2a9SEric Dumazet w -= nexthop_nh->nh_power; 13156a31d2a9SEric Dumazet if (w <= 0) { 131671fceff0SDavid S. Miller nexthop_nh->nh_power--; 13171da177e4SLinus Torvalds fi->fib_power--; 13181da177e4SLinus Torvalds res->nh_sel = nhsel; 13191da177e4SLinus Torvalds spin_unlock_bh(&fib_multipath_lock); 13201da177e4SLinus Torvalds return; 13211da177e4SLinus Torvalds } 13221da177e4SLinus Torvalds } 13231da177e4SLinus Torvalds } endfor_nexthops(fi); 13241da177e4SLinus Torvalds 13251da177e4SLinus Torvalds /* Race condition: route has just become dead. */ 13261da177e4SLinus Torvalds res->nh_sel = 0; 13271da177e4SLinus Torvalds spin_unlock_bh(&fib_multipath_lock); 13281da177e4SLinus Torvalds } 13291da177e4SLinus Torvalds #endif 1330