| 1 | /* |
| 2 | * INET An implementation of the TCP/IP protocol suite for the LINUX |
| 3 | * operating system. INET is implemented using the BSD Socket |
| 4 | * interface as the means of communication with the user level. |
| 5 | * |
| 6 | * The User Datagram Protocol (UDP). |
| 7 | * |
| 8 | * Authors: Ross Biro |
| 9 | * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> |
| 10 | * Arnt Gulbrandsen, <agulbra@nvg.unit.no> |
| 11 | * Alan Cox, <alan@lxorguk.ukuu.org.uk> |
| 12 | * Hirokazu Takahashi, <taka@valinux.co.jp> |
| 13 | * |
| 14 | * Fixes: |
| 15 | * Alan Cox : verify_area() calls |
| 16 | * Alan Cox : stopped close while in use off icmp |
| 17 | * messages. Not a fix but a botch that |
| 18 | * for udp at least is 'valid'. |
| 19 | * Alan Cox : Fixed icmp handling properly |
| 20 | * Alan Cox : Correct error for oversized datagrams |
| 21 | * Alan Cox : Tidied select() semantics. |
| 22 | * Alan Cox : udp_err() fixed properly, also now |
| 23 | * select and read wake correctly on errors |
| 24 | * Alan Cox : udp_send verify_area moved to avoid mem leak |
| 25 | * Alan Cox : UDP can count its memory |
| 26 | * Alan Cox : send to an unknown connection causes |
| 27 | * an ECONNREFUSED off the icmp, but |
| 28 | * does NOT close. |
| 29 | * Alan Cox : Switched to new sk_buff handlers. No more backlog! |
| 30 | * Alan Cox : Using generic datagram code. Even smaller and the PEEK |
| 31 | * bug no longer crashes it. |
| 32 | * Fred Van Kempen : Net2e support for sk->broadcast. |
| 33 | * Alan Cox : Uses skb_free_datagram |
| 34 | * Alan Cox : Added get/set sockopt support. |
| 35 | * Alan Cox : Broadcasting without option set returns EACCES. |
| 36 | * Alan Cox : No wakeup calls. Instead we now use the callbacks. |
| 37 | * Alan Cox : Use ip_tos and ip_ttl |
| 38 | * Alan Cox : SNMP Mibs |
| 39 | * Alan Cox : MSG_DONTROUTE, and 0.0.0.0 support. |
| 40 | * Matt Dillon : UDP length checks. |
| 41 | * Alan Cox : Smarter af_inet used properly. |
| 42 | * Alan Cox : Use new kernel side addressing. |
| 43 | * Alan Cox : Incorrect return on truncated datagram receive. |
| 44 | * Arnt Gulbrandsen : New udp_send and stuff |
| 45 | * Alan Cox : Cache last socket |
| 46 | * Alan Cox : Route cache |
| 47 | * Jon Peatfield : Minor efficiency fix to sendto(). |
| 48 | * Mike Shaver : RFC1122 checks. |
| 49 | * Alan Cox : Nonblocking error fix. |
| 50 | * Willy Konynenberg : Transparent proxying support. |
| 51 | * Mike McLagan : Routing by source |
| 52 | * David S. Miller : New socket lookup architecture. |
| 53 | * Last socket cache retained as it |
| 54 | * does have a high hit rate. |
| 55 | * Olaf Kirch : Don't linearise iovec on sendmsg. |
| 56 | * Andi Kleen : Some cleanups, cache destination entry |
| 57 | * for connect. |
| 58 | * Vitaly E. Lavrov : Transparent proxy revived after year coma. |
| 59 | * Melvin Smith : Check msg_name not msg_namelen in sendto(), |
| 60 | * return ENOTCONN for unconnected sockets (POSIX) |
| 61 | * Janos Farkas : don't deliver multi/broadcasts to a different |
| 62 | * bound-to-device socket |
| 63 | * Hirokazu Takahashi : HW checksumming for outgoing UDP |
| 64 | * datagrams. |
| 65 | * Hirokazu Takahashi : sendfile() on UDP works now. |
| 66 | * Arnaldo C. Melo : convert /proc/net/udp to seq_file |
| 67 | * YOSHIFUJI Hideaki @USAGI and: Support IPV6_V6ONLY socket option, which |
| 68 | * Alexey Kuznetsov: allow both IPv4 and IPv6 sockets to bind |
| 69 | * a single port at the same time. |
| 70 | * Derek Atkins <derek@ihtfp.com>: Add Encapulation Support |
| 71 | * James Chapman : Add L2TP encapsulation type. |
| 72 | * |
| 73 | * |
| 74 | * This program is free software; you can redistribute it and/or |
| 75 | * modify it under the terms of the GNU General Public License |
| 76 | * as published by the Free Software Foundation; either version |
| 77 | * 2 of the License, or (at your option) any later version. |
| 78 | */ |
| 79 | |
| 80 | #define pr_fmt(fmt) "UDP: " fmt |
| 81 | |
| 82 | #include <asm/uaccess.h> |
| 83 | #include <asm/ioctls.h> |
| 84 | #include <linux/bootmem.h> |
| 85 | #include <linux/highmem.h> |
| 86 | #include <linux/swap.h> |
| 87 | #include <linux/types.h> |
| 88 | #include <linux/fcntl.h> |
| 89 | #include <linux/module.h> |
| 90 | #include <linux/socket.h> |
| 91 | #include <linux/sockios.h> |
| 92 | #include <linux/igmp.h> |
| 93 | #include <linux/in.h> |
| 94 | #include <linux/errno.h> |
| 95 | #include <linux/timer.h> |
| 96 | #include <linux/mm.h> |
| 97 | #include <linux/inet.h> |
| 98 | #include <linux/netdevice.h> |
| 99 | #include <linux/slab.h> |
| 100 | #include <net/tcp_states.h> |
| 101 | #include <linux/skbuff.h> |
| 102 | #include <linux/proc_fs.h> |
| 103 | #include <linux/seq_file.h> |
| 104 | #include <net/net_namespace.h> |
| 105 | #include <net/icmp.h> |
| 106 | #include <net/route.h> |
| 107 | #include <net/checksum.h> |
| 108 | #include <net/xfrm.h> |
| 109 | #include <trace/events/udp.h> |
| 110 | #include <linux/static_key.h> |
| 111 | #include <trace/events/skb.h> |
| 112 | #include "udp_impl.h" |
| 113 | |
| 114 | struct udp_table udp_table __read_mostly; |
| 115 | EXPORT_SYMBOL(udp_table); |
| 116 | |
| 117 | long sysctl_udp_mem[3] __read_mostly; |
| 118 | EXPORT_SYMBOL(sysctl_udp_mem); |
| 119 | |
| 120 | int sysctl_udp_rmem_min __read_mostly; |
| 121 | EXPORT_SYMBOL(sysctl_udp_rmem_min); |
| 122 | |
| 123 | int sysctl_udp_wmem_min __read_mostly; |
| 124 | EXPORT_SYMBOL(sysctl_udp_wmem_min); |
| 125 | |
| 126 | atomic_long_t udp_memory_allocated; |
| 127 | EXPORT_SYMBOL(udp_memory_allocated); |
| 128 | |
| 129 | #define MAX_UDP_PORTS 65536 |
| 130 | #define PORTS_PER_CHAIN (MAX_UDP_PORTS / UDP_HTABLE_SIZE_MIN) |
| 131 | |
| 132 | static int udp_lib_lport_inuse(struct net *net, __u16 num, |
| 133 | const struct udp_hslot *hslot, |
| 134 | unsigned long *bitmap, |
| 135 | struct sock *sk, |
| 136 | int (*saddr_comp)(const struct sock *sk1, |
| 137 | const struct sock *sk2), |
| 138 | unsigned int log) |
| 139 | { |
| 140 | struct sock *sk2; |
| 141 | struct hlist_nulls_node *node; |
| 142 | kuid_t uid = sock_i_uid(sk); |
| 143 | |
| 144 | sk_nulls_for_each(sk2, node, &hslot->head) |
| 145 | if (net_eq(sock_net(sk2), net) && |
| 146 | sk2 != sk && |
| 147 | (bitmap || udp_sk(sk2)->udp_port_hash == num) && |
| 148 | (!sk2->sk_reuse || !sk->sk_reuse) && |
| 149 | (!sk2->sk_bound_dev_if || !sk->sk_bound_dev_if || |
| 150 | sk2->sk_bound_dev_if == sk->sk_bound_dev_if) && |
| 151 | (!sk2->sk_reuseport || !sk->sk_reuseport || |
| 152 | !uid_eq(uid, sock_i_uid(sk2))) && |
| 153 | (*saddr_comp)(sk, sk2)) { |
| 154 | if (bitmap) |
| 155 | __set_bit(udp_sk(sk2)->udp_port_hash >> log, |
| 156 | bitmap); |
| 157 | else |
| 158 | return 1; |
| 159 | } |
| 160 | return 0; |
| 161 | } |
| 162 | |
| 163 | /* |
| 164 | * Note: we still hold spinlock of primary hash chain, so no other writer |
| 165 | * can insert/delete a socket with local_port == num |
| 166 | */ |
| 167 | static int udp_lib_lport_inuse2(struct net *net, __u16 num, |
| 168 | struct udp_hslot *hslot2, |
| 169 | struct sock *sk, |
| 170 | int (*saddr_comp)(const struct sock *sk1, |
| 171 | const struct sock *sk2)) |
| 172 | { |
| 173 | struct sock *sk2; |
| 174 | struct hlist_nulls_node *node; |
| 175 | kuid_t uid = sock_i_uid(sk); |
| 176 | int res = 0; |
| 177 | |
| 178 | spin_lock(&hslot2->lock); |
| 179 | udp_portaddr_for_each_entry(sk2, node, &hslot2->head) |
| 180 | if (net_eq(sock_net(sk2), net) && |
| 181 | sk2 != sk && |
| 182 | (udp_sk(sk2)->udp_port_hash == num) && |
| 183 | (!sk2->sk_reuse || !sk->sk_reuse) && |
| 184 | (!sk2->sk_bound_dev_if || !sk->sk_bound_dev_if || |
| 185 | sk2->sk_bound_dev_if == sk->sk_bound_dev_if) && |
| 186 | (!sk2->sk_reuseport || !sk->sk_reuseport || |
| 187 | !uid_eq(uid, sock_i_uid(sk2))) && |
| 188 | (*saddr_comp)(sk, sk2)) { |
| 189 | res = 1; |
| 190 | break; |
| 191 | } |
| 192 | spin_unlock(&hslot2->lock); |
| 193 | return res; |
| 194 | } |
| 195 | |
| 196 | /** |
| 197 | * udp_lib_get_port - UDP/-Lite port lookup for IPv4 and IPv6 |
| 198 | * |
| 199 | * @sk: socket struct in question |
| 200 | * @snum: port number to look up |
| 201 | * @saddr_comp: AF-dependent comparison of bound local IP addresses |
| 202 | * @hash2_nulladdr: AF-dependent hash value in secondary hash chains, |
| 203 | * with NULL address |
| 204 | */ |
| 205 | int udp_lib_get_port(struct sock *sk, unsigned short snum, |
| 206 | int (*saddr_comp)(const struct sock *sk1, |
| 207 | const struct sock *sk2), |
| 208 | unsigned int hash2_nulladdr) |
| 209 | { |
| 210 | struct udp_hslot *hslot, *hslot2; |
| 211 | struct udp_table *udptable = sk->sk_prot->h.udp_table; |
| 212 | int error = 1; |
| 213 | struct net *net = sock_net(sk); |
| 214 | |
| 215 | if (!snum) { |
| 216 | int low, high, remaining; |
| 217 | unsigned int rand; |
| 218 | unsigned short first, last; |
| 219 | DECLARE_BITMAP(bitmap, PORTS_PER_CHAIN); |
| 220 | |
| 221 | inet_get_local_port_range(&low, &high); |
| 222 | remaining = (high - low) + 1; |
| 223 | |
| 224 | rand = net_random(); |
| 225 | first = (((u64)rand * remaining) >> 32) + low; |
| 226 | /* |
| 227 | * force rand to be an odd multiple of UDP_HTABLE_SIZE |
| 228 | */ |
| 229 | rand = (rand | 1) * (udptable->mask + 1); |
| 230 | last = first + udptable->mask + 1; |
| 231 | do { |
| 232 | hslot = udp_hashslot(udptable, net, first); |
| 233 | bitmap_zero(bitmap, PORTS_PER_CHAIN); |
| 234 | spin_lock_bh(&hslot->lock); |
| 235 | udp_lib_lport_inuse(net, snum, hslot, bitmap, sk, |
| 236 | saddr_comp, udptable->log); |
| 237 | |
| 238 | snum = first; |
| 239 | /* |
| 240 | * Iterate on all possible values of snum for this hash. |
| 241 | * Using steps of an odd multiple of UDP_HTABLE_SIZE |
| 242 | * give us randomization and full range coverage. |
| 243 | */ |
| 244 | do { |
| 245 | if (low <= snum && snum <= high && |
| 246 | !test_bit(snum >> udptable->log, bitmap) && |
| 247 | !inet_is_reserved_local_port(snum)) |
| 248 | goto found; |
| 249 | snum += rand; |
| 250 | } while (snum != first); |
| 251 | spin_unlock_bh(&hslot->lock); |
| 252 | } while (++first != last); |
| 253 | goto fail; |
| 254 | } else { |
| 255 | hslot = udp_hashslot(udptable, net, snum); |
| 256 | spin_lock_bh(&hslot->lock); |
| 257 | if (hslot->count > 10) { |
| 258 | int exist; |
| 259 | unsigned int slot2 = udp_sk(sk)->udp_portaddr_hash ^ snum; |
| 260 | |
| 261 | slot2 &= udptable->mask; |
| 262 | hash2_nulladdr &= udptable->mask; |
| 263 | |
| 264 | hslot2 = udp_hashslot2(udptable, slot2); |
| 265 | if (hslot->count < hslot2->count) |
| 266 | goto scan_primary_hash; |
| 267 | |
| 268 | exist = udp_lib_lport_inuse2(net, snum, hslot2, |
| 269 | sk, saddr_comp); |
| 270 | if (!exist && (hash2_nulladdr != slot2)) { |
| 271 | hslot2 = udp_hashslot2(udptable, hash2_nulladdr); |
| 272 | exist = udp_lib_lport_inuse2(net, snum, hslot2, |
| 273 | sk, saddr_comp); |
| 274 | } |
| 275 | if (exist) |
| 276 | goto fail_unlock; |
| 277 | else |
| 278 | goto found; |
| 279 | } |
| 280 | scan_primary_hash: |
| 281 | if (udp_lib_lport_inuse(net, snum, hslot, NULL, sk, |
| 282 | saddr_comp, 0)) |
| 283 | goto fail_unlock; |
| 284 | } |
| 285 | found: |
| 286 | inet_sk(sk)->inet_num = snum; |
| 287 | udp_sk(sk)->udp_port_hash = snum; |
| 288 | udp_sk(sk)->udp_portaddr_hash ^= snum; |
| 289 | if (sk_unhashed(sk)) { |
| 290 | sk_nulls_add_node_rcu(sk, &hslot->head); |
| 291 | hslot->count++; |
| 292 | sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1); |
| 293 | |
| 294 | hslot2 = udp_hashslot2(udptable, udp_sk(sk)->udp_portaddr_hash); |
| 295 | spin_lock(&hslot2->lock); |
| 296 | hlist_nulls_add_head_rcu(&udp_sk(sk)->udp_portaddr_node, |
| 297 | &hslot2->head); |
| 298 | hslot2->count++; |
| 299 | spin_unlock(&hslot2->lock); |
| 300 | } |
| 301 | error = 0; |
| 302 | fail_unlock: |
| 303 | spin_unlock_bh(&hslot->lock); |
| 304 | fail: |
| 305 | return error; |
| 306 | } |
| 307 | EXPORT_SYMBOL(udp_lib_get_port); |
| 308 | |
| 309 | static int ipv4_rcv_saddr_equal(const struct sock *sk1, const struct sock *sk2) |
| 310 | { |
| 311 | struct inet_sock *inet1 = inet_sk(sk1), *inet2 = inet_sk(sk2); |
| 312 | |
| 313 | return (!ipv6_only_sock(sk2) && |
| 314 | (!inet1->inet_rcv_saddr || !inet2->inet_rcv_saddr || |
| 315 | inet1->inet_rcv_saddr == inet2->inet_rcv_saddr)); |
| 316 | } |
| 317 | |
| 318 | static unsigned int udp4_portaddr_hash(struct net *net, __be32 saddr, |
| 319 | unsigned int port) |
| 320 | { |
| 321 | return jhash_1word((__force u32)saddr, net_hash_mix(net)) ^ port; |
| 322 | } |
| 323 | |
| 324 | int udp_v4_get_port(struct sock *sk, unsigned short snum) |
| 325 | { |
| 326 | unsigned int hash2_nulladdr = |
| 327 | udp4_portaddr_hash(sock_net(sk), htonl(INADDR_ANY), snum); |
| 328 | unsigned int hash2_partial = |
| 329 | udp4_portaddr_hash(sock_net(sk), inet_sk(sk)->inet_rcv_saddr, 0); |
| 330 | |
| 331 | /* precompute partial secondary hash */ |
| 332 | udp_sk(sk)->udp_portaddr_hash = hash2_partial; |
| 333 | return udp_lib_get_port(sk, snum, ipv4_rcv_saddr_equal, hash2_nulladdr); |
| 334 | } |
| 335 | |
| 336 | static inline int compute_score(struct sock *sk, struct net *net, __be32 saddr, |
| 337 | unsigned short hnum, |
| 338 | __be16 sport, __be32 daddr, __be16 dport, int dif) |
| 339 | { |
| 340 | int score = -1; |
| 341 | |
| 342 | if (net_eq(sock_net(sk), net) && udp_sk(sk)->udp_port_hash == hnum && |
| 343 | !ipv6_only_sock(sk)) { |
| 344 | struct inet_sock *inet = inet_sk(sk); |
| 345 | |
| 346 | score = (sk->sk_family == PF_INET ? 2 : 1); |
| 347 | if (inet->inet_rcv_saddr) { |
| 348 | if (inet->inet_rcv_saddr != daddr) |
| 349 | return -1; |
| 350 | score += 4; |
| 351 | } |
| 352 | if (inet->inet_daddr) { |
| 353 | if (inet->inet_daddr != saddr) |
| 354 | return -1; |
| 355 | score += 4; |
| 356 | } |
| 357 | if (inet->inet_dport) { |
| 358 | if (inet->inet_dport != sport) |
| 359 | return -1; |
| 360 | score += 4; |
| 361 | } |
| 362 | if (sk->sk_bound_dev_if) { |
| 363 | if (sk->sk_bound_dev_if != dif) |
| 364 | return -1; |
| 365 | score += 4; |
| 366 | } |
| 367 | } |
| 368 | return score; |
| 369 | } |
| 370 | |
| 371 | /* |
| 372 | * In this second variant, we check (daddr, dport) matches (inet_rcv_sadd, inet_num) |
| 373 | */ |
| 374 | static inline int compute_score2(struct sock *sk, struct net *net, |
| 375 | __be32 saddr, __be16 sport, |
| 376 | __be32 daddr, unsigned int hnum, int dif) |
| 377 | { |
| 378 | int score = -1; |
| 379 | |
| 380 | if (net_eq(sock_net(sk), net) && !ipv6_only_sock(sk)) { |
| 381 | struct inet_sock *inet = inet_sk(sk); |
| 382 | |
| 383 | if (inet->inet_rcv_saddr != daddr) |
| 384 | return -1; |
| 385 | if (inet->inet_num != hnum) |
| 386 | return -1; |
| 387 | |
| 388 | score = (sk->sk_family == PF_INET ? 2 : 1); |
| 389 | if (inet->inet_daddr) { |
| 390 | if (inet->inet_daddr != saddr) |
| 391 | return -1; |
| 392 | score += 4; |
| 393 | } |
| 394 | if (inet->inet_dport) { |
| 395 | if (inet->inet_dport != sport) |
| 396 | return -1; |
| 397 | score += 4; |
| 398 | } |
| 399 | if (sk->sk_bound_dev_if) { |
| 400 | if (sk->sk_bound_dev_if != dif) |
| 401 | return -1; |
| 402 | score += 4; |
| 403 | } |
| 404 | } |
| 405 | return score; |
| 406 | } |
| 407 | |
| 408 | |
| 409 | /* called with read_rcu_lock() */ |
| 410 | static struct sock *udp4_lib_lookup2(struct net *net, |
| 411 | __be32 saddr, __be16 sport, |
| 412 | __be32 daddr, unsigned int hnum, int dif, |
| 413 | struct udp_hslot *hslot2, unsigned int slot2) |
| 414 | { |
| 415 | struct sock *sk, *result; |
| 416 | struct hlist_nulls_node *node; |
| 417 | int score, badness, matches = 0, reuseport = 0; |
| 418 | u32 hash = 0; |
| 419 | |
| 420 | begin: |
| 421 | result = NULL; |
| 422 | badness = 0; |
| 423 | udp_portaddr_for_each_entry_rcu(sk, node, &hslot2->head) { |
| 424 | score = compute_score2(sk, net, saddr, sport, |
| 425 | daddr, hnum, dif); |
| 426 | if (score > badness) { |
| 427 | result = sk; |
| 428 | badness = score; |
| 429 | reuseport = sk->sk_reuseport; |
| 430 | if (reuseport) { |
| 431 | hash = inet_ehashfn(net, daddr, hnum, |
| 432 | saddr, htons(sport)); |
| 433 | matches = 1; |
| 434 | } |
| 435 | } else if (score == badness && reuseport) { |
| 436 | matches++; |
| 437 | if (((u64)hash * matches) >> 32 == 0) |
| 438 | result = sk; |
| 439 | hash = next_pseudo_random32(hash); |
| 440 | } |
| 441 | } |
| 442 | /* |
| 443 | * if the nulls value we got at the end of this lookup is |
| 444 | * not the expected one, we must restart lookup. |
| 445 | * We probably met an item that was moved to another chain. |
| 446 | */ |
| 447 | if (get_nulls_value(node) != slot2) |
| 448 | goto begin; |
| 449 | if (result) { |
| 450 | if (unlikely(!atomic_inc_not_zero_hint(&result->sk_refcnt, 2))) |
| 451 | result = NULL; |
| 452 | else if (unlikely(compute_score2(result, net, saddr, sport, |
| 453 | daddr, hnum, dif) < badness)) { |
| 454 | sock_put(result); |
| 455 | goto begin; |
| 456 | } |
| 457 | } |
| 458 | return result; |
| 459 | } |
| 460 | |
| 461 | /* UDP is nearly always wildcards out the wazoo, it makes no sense to try |
| 462 | * harder than this. -DaveM |
| 463 | */ |
| 464 | struct sock *__udp4_lib_lookup(struct net *net, __be32 saddr, |
| 465 | __be16 sport, __be32 daddr, __be16 dport, |
| 466 | int dif, struct udp_table *udptable) |
| 467 | { |
| 468 | struct sock *sk, *result; |
| 469 | struct hlist_nulls_node *node; |
| 470 | unsigned short hnum = ntohs(dport); |
| 471 | unsigned int hash2, slot2, slot = udp_hashfn(net, hnum, udptable->mask); |
| 472 | struct udp_hslot *hslot2, *hslot = &udptable->hash[slot]; |
| 473 | int score, badness, matches = 0, reuseport = 0; |
| 474 | u32 hash = 0; |
| 475 | |
| 476 | rcu_read_lock(); |
| 477 | if (hslot->count > 10) { |
| 478 | hash2 = udp4_portaddr_hash(net, daddr, hnum); |
| 479 | slot2 = hash2 & udptable->mask; |
| 480 | hslot2 = &udptable->hash2[slot2]; |
| 481 | if (hslot->count < hslot2->count) |
| 482 | goto begin; |
| 483 | |
| 484 | result = udp4_lib_lookup2(net, saddr, sport, |
| 485 | daddr, hnum, dif, |
| 486 | hslot2, slot2); |
| 487 | if (!result) { |
| 488 | hash2 = udp4_portaddr_hash(net, htonl(INADDR_ANY), hnum); |
| 489 | slot2 = hash2 & udptable->mask; |
| 490 | hslot2 = &udptable->hash2[slot2]; |
| 491 | if (hslot->count < hslot2->count) |
| 492 | goto begin; |
| 493 | |
| 494 | result = udp4_lib_lookup2(net, saddr, sport, |
| 495 | htonl(INADDR_ANY), hnum, dif, |
| 496 | hslot2, slot2); |
| 497 | } |
| 498 | rcu_read_unlock(); |
| 499 | return result; |
| 500 | } |
| 501 | begin: |
| 502 | result = NULL; |
| 503 | badness = 0; |
| 504 | sk_nulls_for_each_rcu(sk, node, &hslot->head) { |
| 505 | score = compute_score(sk, net, saddr, hnum, sport, |
| 506 | daddr, dport, dif); |
| 507 | if (score > badness) { |
| 508 | result = sk; |
| 509 | badness = score; |
| 510 | reuseport = sk->sk_reuseport; |
| 511 | if (reuseport) { |
| 512 | hash = inet_ehashfn(net, daddr, hnum, |
| 513 | saddr, htons(sport)); |
| 514 | matches = 1; |
| 515 | } |
| 516 | } else if (score == badness && reuseport) { |
| 517 | matches++; |
| 518 | if (((u64)hash * matches) >> 32 == 0) |
| 519 | result = sk; |
| 520 | hash = next_pseudo_random32(hash); |
| 521 | } |
| 522 | } |
| 523 | /* |
| 524 | * if the nulls value we got at the end of this lookup is |
| 525 | * not the expected one, we must restart lookup. |
| 526 | * We probably met an item that was moved to another chain. |
| 527 | */ |
| 528 | if (get_nulls_value(node) != slot) |
| 529 | goto begin; |
| 530 | |
| 531 | if (result) { |
| 532 | if (unlikely(!atomic_inc_not_zero_hint(&result->sk_refcnt, 2))) |
| 533 | result = NULL; |
| 534 | else if (unlikely(compute_score(result, net, saddr, hnum, sport, |
| 535 | daddr, dport, dif) < badness)) { |
| 536 | sock_put(result); |
| 537 | goto begin; |
| 538 | } |
| 539 | } |
| 540 | rcu_read_unlock(); |
| 541 | return result; |
| 542 | } |
| 543 | EXPORT_SYMBOL_GPL(__udp4_lib_lookup); |
| 544 | |
| 545 | static inline struct sock *__udp4_lib_lookup_skb(struct sk_buff *skb, |
| 546 | __be16 sport, __be16 dport, |
| 547 | struct udp_table *udptable) |
| 548 | { |
| 549 | struct sock *sk; |
| 550 | const struct iphdr *iph = ip_hdr(skb); |
| 551 | |
| 552 | if (unlikely(sk = skb_steal_sock(skb))) |
| 553 | return sk; |
| 554 | else |
| 555 | return __udp4_lib_lookup(dev_net(skb_dst(skb)->dev), iph->saddr, sport, |
| 556 | iph->daddr, dport, inet_iif(skb), |
| 557 | udptable); |
| 558 | } |
| 559 | |
| 560 | struct sock *udp4_lib_lookup(struct net *net, __be32 saddr, __be16 sport, |
| 561 | __be32 daddr, __be16 dport, int dif) |
| 562 | { |
| 563 | return __udp4_lib_lookup(net, saddr, sport, daddr, dport, dif, &udp_table); |
| 564 | } |
| 565 | EXPORT_SYMBOL_GPL(udp4_lib_lookup); |
| 566 | |
| 567 | static inline struct sock *udp_v4_mcast_next(struct net *net, struct sock *sk, |
| 568 | __be16 loc_port, __be32 loc_addr, |
| 569 | __be16 rmt_port, __be32 rmt_addr, |
| 570 | int dif) |
| 571 | { |
| 572 | struct hlist_nulls_node *node; |
| 573 | struct sock *s = sk; |
| 574 | unsigned short hnum = ntohs(loc_port); |
| 575 | |
| 576 | sk_nulls_for_each_from(s, node) { |
| 577 | struct inet_sock *inet = inet_sk(s); |
| 578 | |
| 579 | if (!net_eq(sock_net(s), net) || |
| 580 | udp_sk(s)->udp_port_hash != hnum || |
| 581 | (inet->inet_daddr && inet->inet_daddr != rmt_addr) || |
| 582 | (inet->inet_dport != rmt_port && inet->inet_dport) || |
| 583 | (inet->inet_rcv_saddr && |
| 584 | inet->inet_rcv_saddr != loc_addr) || |
| 585 | ipv6_only_sock(s) || |
| 586 | (s->sk_bound_dev_if && s->sk_bound_dev_if != dif)) |
| 587 | continue; |
| 588 | if (!ip_mc_sf_allow(s, loc_addr, rmt_addr, dif)) |
| 589 | continue; |
| 590 | goto found; |
| 591 | } |
| 592 | s = NULL; |
| 593 | found: |
| 594 | return s; |
| 595 | } |
| 596 | |
| 597 | /* |
| 598 | * This routine is called by the ICMP module when it gets some |
| 599 | * sort of error condition. If err < 0 then the socket should |
| 600 | * be closed and the error returned to the user. If err > 0 |
| 601 | * it's just the icmp type << 8 | icmp code. |
| 602 | * Header points to the ip header of the error packet. We move |
| 603 | * on past this. Then (as it used to claim before adjustment) |
| 604 | * header points to the first 8 bytes of the udp header. We need |
| 605 | * to find the appropriate port. |
| 606 | */ |
| 607 | |
| 608 | void __udp4_lib_err(struct sk_buff *skb, u32 info, struct udp_table *udptable) |
| 609 | { |
| 610 | struct inet_sock *inet; |
| 611 | const struct iphdr *iph = (const struct iphdr *)skb->data; |
| 612 | struct udphdr *uh = (struct udphdr *)(skb->data+(iph->ihl<<2)); |
| 613 | const int type = icmp_hdr(skb)->type; |
| 614 | const int code = icmp_hdr(skb)->code; |
| 615 | struct sock *sk; |
| 616 | int harderr; |
| 617 | int err; |
| 618 | struct net *net = dev_net(skb->dev); |
| 619 | |
| 620 | sk = __udp4_lib_lookup(net, iph->daddr, uh->dest, |
| 621 | iph->saddr, uh->source, skb->dev->ifindex, udptable); |
| 622 | if (sk == NULL) { |
| 623 | ICMP_INC_STATS_BH(net, ICMP_MIB_INERRORS); |
| 624 | return; /* No socket for error */ |
| 625 | } |
| 626 | |
| 627 | err = 0; |
| 628 | harderr = 0; |
| 629 | inet = inet_sk(sk); |
| 630 | |
| 631 | switch (type) { |
| 632 | default: |
| 633 | case ICMP_TIME_EXCEEDED: |
| 634 | err = EHOSTUNREACH; |
| 635 | break; |
| 636 | case ICMP_SOURCE_QUENCH: |
| 637 | goto out; |
| 638 | case ICMP_PARAMETERPROB: |
| 639 | err = EPROTO; |
| 640 | harderr = 1; |
| 641 | break; |
| 642 | case ICMP_DEST_UNREACH: |
| 643 | if (code == ICMP_FRAG_NEEDED) { /* Path MTU discovery */ |
| 644 | ipv4_sk_update_pmtu(skb, sk, info); |
| 645 | if (inet->pmtudisc != IP_PMTUDISC_DONT) { |
| 646 | err = EMSGSIZE; |
| 647 | harderr = 1; |
| 648 | break; |
| 649 | } |
| 650 | goto out; |
| 651 | } |
| 652 | err = EHOSTUNREACH; |
| 653 | if (code <= NR_ICMP_UNREACH) { |
| 654 | harderr = icmp_err_convert[code].fatal; |
| 655 | err = icmp_err_convert[code].errno; |
| 656 | } |
| 657 | break; |
| 658 | case ICMP_REDIRECT: |
| 659 | ipv4_sk_redirect(skb, sk); |
| 660 | break; |
| 661 | } |
| 662 | |
| 663 | /* |
| 664 | * RFC1122: OK. Passes ICMP errors back to application, as per |
| 665 | * 4.1.3.3. |
| 666 | */ |
| 667 | if (!inet->recverr) { |
| 668 | if (!harderr || sk->sk_state != TCP_ESTABLISHED) |
| 669 | goto out; |
| 670 | } else |
| 671 | ip_icmp_error(sk, skb, err, uh->dest, info, (u8 *)(uh+1)); |
| 672 | |
| 673 | sk->sk_err = err; |
| 674 | sk->sk_error_report(sk); |
| 675 | out: |
| 676 | sock_put(sk); |
| 677 | } |
| 678 | |
| 679 | void udp_err(struct sk_buff *skb, u32 info) |
| 680 | { |
| 681 | __udp4_lib_err(skb, info, &udp_table); |
| 682 | } |
| 683 | |
| 684 | /* |
| 685 | * Throw away all pending data and cancel the corking. Socket is locked. |
| 686 | */ |
| 687 | void udp_flush_pending_frames(struct sock *sk) |
| 688 | { |
| 689 | struct udp_sock *up = udp_sk(sk); |
| 690 | |
| 691 | if (up->pending) { |
| 692 | up->len = 0; |
| 693 | up->pending = 0; |
| 694 | ip_flush_pending_frames(sk); |
| 695 | } |
| 696 | } |
| 697 | EXPORT_SYMBOL(udp_flush_pending_frames); |
| 698 | |
| 699 | /** |
| 700 | * udp4_hwcsum - handle outgoing HW checksumming |
| 701 | * @skb: sk_buff containing the filled-in UDP header |
| 702 | * (checksum field must be zeroed out) |
| 703 | * @src: source IP address |
| 704 | * @dst: destination IP address |
| 705 | */ |
| 706 | static void udp4_hwcsum(struct sk_buff *skb, __be32 src, __be32 dst) |
| 707 | { |
| 708 | struct udphdr *uh = udp_hdr(skb); |
| 709 | struct sk_buff *frags = skb_shinfo(skb)->frag_list; |
| 710 | int offset = skb_transport_offset(skb); |
| 711 | int len = skb->len - offset; |
| 712 | int hlen = len; |
| 713 | __wsum csum = 0; |
| 714 | |
| 715 | if (!frags) { |
| 716 | /* |
| 717 | * Only one fragment on the socket. |
| 718 | */ |
| 719 | skb->csum_start = skb_transport_header(skb) - skb->head; |
| 720 | skb->csum_offset = offsetof(struct udphdr, check); |
| 721 | uh->check = ~csum_tcpudp_magic(src, dst, len, |
| 722 | IPPROTO_UDP, 0); |
| 723 | } else { |
| 724 | /* |
| 725 | * HW-checksum won't work as there are two or more |
| 726 | * fragments on the socket so that all csums of sk_buffs |
| 727 | * should be together |
| 728 | */ |
| 729 | do { |
| 730 | csum = csum_add(csum, frags->csum); |
| 731 | hlen -= frags->len; |
| 732 | } while ((frags = frags->next)); |
| 733 | |
| 734 | csum = skb_checksum(skb, offset, hlen, csum); |
| 735 | skb->ip_summed = CHECKSUM_NONE; |
| 736 | |
| 737 | uh->check = csum_tcpudp_magic(src, dst, len, IPPROTO_UDP, csum); |
| 738 | if (uh->check == 0) |
| 739 | uh->check = CSUM_MANGLED_0; |
| 740 | } |
| 741 | } |
| 742 | |
| 743 | static int udp_send_skb(struct sk_buff *skb, struct flowi4 *fl4) |
| 744 | { |
| 745 | struct sock *sk = skb->sk; |
| 746 | struct inet_sock *inet = inet_sk(sk); |
| 747 | struct udphdr *uh; |
| 748 | int err = 0; |
| 749 | int is_udplite = IS_UDPLITE(sk); |
| 750 | int offset = skb_transport_offset(skb); |
| 751 | int len = skb->len - offset; |
| 752 | __wsum csum = 0; |
| 753 | |
| 754 | /* |
| 755 | * Create a UDP header |
| 756 | */ |
| 757 | uh = udp_hdr(skb); |
| 758 | uh->source = inet->inet_sport; |
| 759 | uh->dest = fl4->fl4_dport; |
| 760 | uh->len = htons(len); |
| 761 | uh->check = 0; |
| 762 | |
| 763 | if (is_udplite) /* UDP-Lite */ |
| 764 | csum = udplite_csum(skb); |
| 765 | |
| 766 | else if (sk->sk_no_check == UDP_CSUM_NOXMIT && !skb_has_frags(skb)) { /* UDP csum off */ |
| 767 | |
| 768 | skb->ip_summed = CHECKSUM_NONE; |
| 769 | goto send; |
| 770 | |
| 771 | } else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */ |
| 772 | |
| 773 | udp4_hwcsum(skb, fl4->saddr, fl4->daddr); |
| 774 | goto send; |
| 775 | |
| 776 | } else |
| 777 | csum = udp_csum(skb); |
| 778 | |
| 779 | /* add protocol-dependent pseudo-header */ |
| 780 | uh->check = csum_tcpudp_magic(fl4->saddr, fl4->daddr, len, |
| 781 | sk->sk_protocol, csum); |
| 782 | if (uh->check == 0) |
| 783 | uh->check = CSUM_MANGLED_0; |
| 784 | |
| 785 | send: |
| 786 | err = ip_send_skb(sock_net(sk), skb); |
| 787 | if (err) { |
| 788 | if (err == -ENOBUFS && !inet->recverr) { |
| 789 | UDP_INC_STATS_USER(sock_net(sk), |
| 790 | UDP_MIB_SNDBUFERRORS, is_udplite); |
| 791 | err = 0; |
| 792 | } |
| 793 | } else |
| 794 | UDP_INC_STATS_USER(sock_net(sk), |
| 795 | UDP_MIB_OUTDATAGRAMS, is_udplite); |
| 796 | return err; |
| 797 | } |
| 798 | |
| 799 | /* |
| 800 | * Push out all pending data as one UDP datagram. Socket is locked. |
| 801 | */ |
| 802 | int udp_push_pending_frames(struct sock *sk) |
| 803 | { |
| 804 | struct udp_sock *up = udp_sk(sk); |
| 805 | struct inet_sock *inet = inet_sk(sk); |
| 806 | struct flowi4 *fl4 = &inet->cork.fl.u.ip4; |
| 807 | struct sk_buff *skb; |
| 808 | int err = 0; |
| 809 | |
| 810 | skb = ip_finish_skb(sk, fl4); |
| 811 | if (!skb) |
| 812 | goto out; |
| 813 | |
| 814 | err = udp_send_skb(skb, fl4); |
| 815 | |
| 816 | out: |
| 817 | up->len = 0; |
| 818 | up->pending = 0; |
| 819 | return err; |
| 820 | } |
| 821 | EXPORT_SYMBOL(udp_push_pending_frames); |
| 822 | |
| 823 | int udp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, |
| 824 | size_t len) |
| 825 | { |
| 826 | struct inet_sock *inet = inet_sk(sk); |
| 827 | struct udp_sock *up = udp_sk(sk); |
| 828 | struct flowi4 fl4_stack; |
| 829 | struct flowi4 *fl4; |
| 830 | int ulen = len; |
| 831 | struct ipcm_cookie ipc; |
| 832 | struct rtable *rt = NULL; |
| 833 | int free = 0; |
| 834 | int connected = 0; |
| 835 | __be32 daddr, faddr, saddr; |
| 836 | __be16 dport; |
| 837 | u8 tos; |
| 838 | int err, is_udplite = IS_UDPLITE(sk); |
| 839 | int corkreq = up->corkflag || msg->msg_flags&MSG_MORE; |
| 840 | int (*getfrag)(void *, char *, int, int, int, struct sk_buff *); |
| 841 | struct sk_buff *skb; |
| 842 | struct ip_options_data opt_copy; |
| 843 | |
| 844 | if (len > 0xFFFF) |
| 845 | return -EMSGSIZE; |
| 846 | |
| 847 | /* |
| 848 | * Check the flags. |
| 849 | */ |
| 850 | |
| 851 | if (msg->msg_flags & MSG_OOB) /* Mirror BSD error message compatibility */ |
| 852 | return -EOPNOTSUPP; |
| 853 | |
| 854 | ipc.opt = NULL; |
| 855 | ipc.tx_flags = 0; |
| 856 | |
| 857 | getfrag = is_udplite ? udplite_getfrag : ip_generic_getfrag; |
| 858 | |
| 859 | fl4 = &inet->cork.fl.u.ip4; |
| 860 | if (up->pending) { |
| 861 | /* |
| 862 | * There are pending frames. |
| 863 | * The socket lock must be held while it's corked. |
| 864 | */ |
| 865 | lock_sock(sk); |
| 866 | if (likely(up->pending)) { |
| 867 | if (unlikely(up->pending != AF_INET)) { |
| 868 | release_sock(sk); |
| 869 | return -EINVAL; |
| 870 | } |
| 871 | goto do_append_data; |
| 872 | } |
| 873 | release_sock(sk); |
| 874 | } |
| 875 | ulen += sizeof(struct udphdr); |
| 876 | |
| 877 | /* |
| 878 | * Get and verify the address. |
| 879 | */ |
| 880 | if (msg->msg_name) { |
| 881 | struct sockaddr_in *usin = (struct sockaddr_in *)msg->msg_name; |
| 882 | if (msg->msg_namelen < sizeof(*usin)) |
| 883 | return -EINVAL; |
| 884 | if (usin->sin_family != AF_INET) { |
| 885 | if (usin->sin_family != AF_UNSPEC) |
| 886 | return -EAFNOSUPPORT; |
| 887 | } |
| 888 | |
| 889 | daddr = usin->sin_addr.s_addr; |
| 890 | dport = usin->sin_port; |
| 891 | if (dport == 0) |
| 892 | return -EINVAL; |
| 893 | } else { |
| 894 | if (sk->sk_state != TCP_ESTABLISHED) |
| 895 | return -EDESTADDRREQ; |
| 896 | daddr = inet->inet_daddr; |
| 897 | dport = inet->inet_dport; |
| 898 | /* Open fast path for connected socket. |
| 899 | Route will not be used, if at least one option is set. |
| 900 | */ |
| 901 | connected = 1; |
| 902 | } |
| 903 | ipc.addr = inet->inet_saddr; |
| 904 | |
| 905 | ipc.oif = sk->sk_bound_dev_if; |
| 906 | |
| 907 | sock_tx_timestamp(sk, &ipc.tx_flags); |
| 908 | |
| 909 | if (msg->msg_controllen) { |
| 910 | err = ip_cmsg_send(sock_net(sk), msg, &ipc); |
| 911 | if (err) |
| 912 | return err; |
| 913 | if (ipc.opt) |
| 914 | free = 1; |
| 915 | connected = 0; |
| 916 | } |
| 917 | if (!ipc.opt) { |
| 918 | struct ip_options_rcu *inet_opt; |
| 919 | |
| 920 | rcu_read_lock(); |
| 921 | inet_opt = rcu_dereference(inet->inet_opt); |
| 922 | if (inet_opt) { |
| 923 | memcpy(&opt_copy, inet_opt, |
| 924 | sizeof(*inet_opt) + inet_opt->opt.optlen); |
| 925 | ipc.opt = &opt_copy.opt; |
| 926 | } |
| 927 | rcu_read_unlock(); |
| 928 | } |
| 929 | |
| 930 | saddr = ipc.addr; |
| 931 | ipc.addr = faddr = daddr; |
| 932 | |
| 933 | if (ipc.opt && ipc.opt->opt.srr) { |
| 934 | if (!daddr) |
| 935 | return -EINVAL; |
| 936 | faddr = ipc.opt->opt.faddr; |
| 937 | connected = 0; |
| 938 | } |
| 939 | tos = RT_TOS(inet->tos); |
| 940 | if (sock_flag(sk, SOCK_LOCALROUTE) || |
| 941 | (msg->msg_flags & MSG_DONTROUTE) || |
| 942 | (ipc.opt && ipc.opt->opt.is_strictroute)) { |
| 943 | tos |= RTO_ONLINK; |
| 944 | connected = 0; |
| 945 | } |
| 946 | |
| 947 | if (ipv4_is_multicast(daddr)) { |
| 948 | if (!ipc.oif) |
| 949 | ipc.oif = inet->mc_index; |
| 950 | if (!saddr) |
| 951 | saddr = inet->mc_addr; |
| 952 | connected = 0; |
| 953 | } else if (!ipc.oif) |
| 954 | ipc.oif = inet->uc_index; |
| 955 | |
| 956 | if (connected) |
| 957 | rt = (struct rtable *)sk_dst_check(sk, 0); |
| 958 | |
| 959 | if (rt == NULL) { |
| 960 | struct net *net = sock_net(sk); |
| 961 | |
| 962 | fl4 = &fl4_stack; |
| 963 | flowi4_init_output(fl4, ipc.oif, sk->sk_mark, tos, |
| 964 | RT_SCOPE_UNIVERSE, sk->sk_protocol, |
| 965 | inet_sk_flowi_flags(sk)|FLOWI_FLAG_CAN_SLEEP, |
| 966 | faddr, saddr, dport, inet->inet_sport, |
| 967 | sk->sk_uid); |
| 968 | |
| 969 | security_sk_classify_flow(sk, flowi4_to_flowi(fl4)); |
| 970 | rt = ip_route_output_flow(net, fl4, sk); |
| 971 | if (IS_ERR(rt)) { |
| 972 | err = PTR_ERR(rt); |
| 973 | rt = NULL; |
| 974 | if (err == -ENETUNREACH) |
| 975 | IP_INC_STATS(net, IPSTATS_MIB_OUTNOROUTES); |
| 976 | goto out; |
| 977 | } |
| 978 | |
| 979 | err = -EACCES; |
| 980 | if ((rt->rt_flags & RTCF_BROADCAST) && |
| 981 | !sock_flag(sk, SOCK_BROADCAST)) |
| 982 | goto out; |
| 983 | if (connected) |
| 984 | sk_dst_set(sk, dst_clone(&rt->dst)); |
| 985 | } |
| 986 | |
| 987 | if (msg->msg_flags&MSG_CONFIRM) |
| 988 | goto do_confirm; |
| 989 | back_from_confirm: |
| 990 | |
| 991 | saddr = fl4->saddr; |
| 992 | if (!ipc.addr) |
| 993 | daddr = ipc.addr = fl4->daddr; |
| 994 | |
| 995 | /* Lockless fast path for the non-corking case. */ |
| 996 | if (!corkreq) { |
| 997 | skb = ip_make_skb(sk, fl4, getfrag, msg->msg_iov, ulen, |
| 998 | sizeof(struct udphdr), &ipc, &rt, |
| 999 | msg->msg_flags); |
| 1000 | err = PTR_ERR(skb); |
| 1001 | if (!IS_ERR_OR_NULL(skb)) |
| 1002 | err = udp_send_skb(skb, fl4); |
| 1003 | goto out; |
| 1004 | } |
| 1005 | |
| 1006 | lock_sock(sk); |
| 1007 | if (unlikely(up->pending)) { |
| 1008 | /* The socket is already corked while preparing it. */ |
| 1009 | /* ... which is an evident application bug. --ANK */ |
| 1010 | release_sock(sk); |
| 1011 | |
| 1012 | LIMIT_NETDEBUG(KERN_DEBUG pr_fmt("cork app bug 2\n")); |
| 1013 | err = -EINVAL; |
| 1014 | goto out; |
| 1015 | } |
| 1016 | /* |
| 1017 | * Now cork the socket to pend data. |
| 1018 | */ |
| 1019 | fl4 = &inet->cork.fl.u.ip4; |
| 1020 | fl4->daddr = daddr; |
| 1021 | fl4->saddr = saddr; |
| 1022 | fl4->fl4_dport = dport; |
| 1023 | fl4->fl4_sport = inet->inet_sport; |
| 1024 | up->pending = AF_INET; |
| 1025 | |
| 1026 | do_append_data: |
| 1027 | up->len += ulen; |
| 1028 | err = ip_append_data(sk, fl4, getfrag, msg->msg_iov, ulen, |
| 1029 | sizeof(struct udphdr), &ipc, &rt, |
| 1030 | corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags); |
| 1031 | if (err) |
| 1032 | udp_flush_pending_frames(sk); |
| 1033 | else if (!corkreq) |
| 1034 | err = udp_push_pending_frames(sk); |
| 1035 | else if (unlikely(skb_queue_empty(&sk->sk_write_queue))) |
| 1036 | up->pending = 0; |
| 1037 | release_sock(sk); |
| 1038 | |
| 1039 | out: |
| 1040 | ip_rt_put(rt); |
| 1041 | if (free) |
| 1042 | kfree(ipc.opt); |
| 1043 | if (!err) |
| 1044 | return len; |
| 1045 | /* |
| 1046 | * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space. Reporting |
| 1047 | * ENOBUFS might not be good (it's not tunable per se), but otherwise |
| 1048 | * we don't have a good statistic (IpOutDiscards but it can be too many |
| 1049 | * things). We could add another new stat but at least for now that |
| 1050 | * seems like overkill. |
| 1051 | */ |
| 1052 | if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) { |
| 1053 | UDP_INC_STATS_USER(sock_net(sk), |
| 1054 | UDP_MIB_SNDBUFERRORS, is_udplite); |
| 1055 | } |
| 1056 | return err; |
| 1057 | |
| 1058 | do_confirm: |
| 1059 | dst_confirm(&rt->dst); |
| 1060 | if (!(msg->msg_flags&MSG_PROBE) || len) |
| 1061 | goto back_from_confirm; |
| 1062 | err = 0; |
| 1063 | goto out; |
| 1064 | } |
| 1065 | EXPORT_SYMBOL(udp_sendmsg); |
| 1066 | |
| 1067 | int udp_sendpage(struct sock *sk, struct page *page, int offset, |
| 1068 | size_t size, int flags) |
| 1069 | { |
| 1070 | struct inet_sock *inet = inet_sk(sk); |
| 1071 | struct udp_sock *up = udp_sk(sk); |
| 1072 | int ret; |
| 1073 | |
| 1074 | if (flags & MSG_SENDPAGE_NOTLAST) |
| 1075 | flags |= MSG_MORE; |
| 1076 | |
| 1077 | if (!up->pending) { |
| 1078 | struct msghdr msg = { .msg_flags = flags|MSG_MORE }; |
| 1079 | |
| 1080 | /* Call udp_sendmsg to specify destination address which |
| 1081 | * sendpage interface can't pass. |
| 1082 | * This will succeed only when the socket is connected. |
| 1083 | */ |
| 1084 | ret = udp_sendmsg(NULL, sk, &msg, 0); |
| 1085 | if (ret < 0) |
| 1086 | return ret; |
| 1087 | } |
| 1088 | |
| 1089 | lock_sock(sk); |
| 1090 | |
| 1091 | if (unlikely(!up->pending)) { |
| 1092 | release_sock(sk); |
| 1093 | |
| 1094 | LIMIT_NETDEBUG(KERN_DEBUG pr_fmt("udp cork app bug 3\n")); |
| 1095 | return -EINVAL; |
| 1096 | } |
| 1097 | |
| 1098 | ret = ip_append_page(sk, &inet->cork.fl.u.ip4, |
| 1099 | page, offset, size, flags); |
| 1100 | if (ret == -EOPNOTSUPP) { |
| 1101 | release_sock(sk); |
| 1102 | return sock_no_sendpage(sk->sk_socket, page, offset, |
| 1103 | size, flags); |
| 1104 | } |
| 1105 | if (ret < 0) { |
| 1106 | udp_flush_pending_frames(sk); |
| 1107 | goto out; |
| 1108 | } |
| 1109 | |
| 1110 | up->len += size; |
| 1111 | if (!(up->corkflag || (flags&MSG_MORE))) |
| 1112 | ret = udp_push_pending_frames(sk); |
| 1113 | if (!ret) |
| 1114 | ret = size; |
| 1115 | out: |
| 1116 | release_sock(sk); |
| 1117 | return ret; |
| 1118 | } |
| 1119 | |
| 1120 | |
| 1121 | /** |
| 1122 | * first_packet_length - return length of first packet in receive queue |
| 1123 | * @sk: socket |
| 1124 | * |
| 1125 | * Drops all bad checksum frames, until a valid one is found. |
| 1126 | * Returns the length of found skb, or 0 if none is found. |
| 1127 | */ |
| 1128 | static unsigned int first_packet_length(struct sock *sk) |
| 1129 | { |
| 1130 | struct sk_buff_head list_kill, *rcvq = &sk->sk_receive_queue; |
| 1131 | struct sk_buff *skb; |
| 1132 | unsigned int res; |
| 1133 | |
| 1134 | __skb_queue_head_init(&list_kill); |
| 1135 | |
| 1136 | spin_lock_bh(&rcvq->lock); |
| 1137 | while ((skb = skb_peek(rcvq)) != NULL && |
| 1138 | udp_lib_checksum_complete(skb)) { |
| 1139 | UDP_INC_STATS_BH(sock_net(sk), UDP_MIB_CSUMERRORS, |
| 1140 | IS_UDPLITE(sk)); |
| 1141 | UDP_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, |
| 1142 | IS_UDPLITE(sk)); |
| 1143 | atomic_inc(&sk->sk_drops); |
| 1144 | __skb_unlink(skb, rcvq); |
| 1145 | __skb_queue_tail(&list_kill, skb); |
| 1146 | } |
| 1147 | res = skb ? skb->len : 0; |
| 1148 | spin_unlock_bh(&rcvq->lock); |
| 1149 | |
| 1150 | if (!skb_queue_empty(&list_kill)) { |
| 1151 | bool slow = lock_sock_fast(sk); |
| 1152 | |
| 1153 | __skb_queue_purge(&list_kill); |
| 1154 | sk_mem_reclaim_partial(sk); |
| 1155 | unlock_sock_fast(sk, slow); |
| 1156 | } |
| 1157 | return res; |
| 1158 | } |
| 1159 | |
| 1160 | /* |
| 1161 | * IOCTL requests applicable to the UDP protocol |
| 1162 | */ |
| 1163 | |
| 1164 | int udp_ioctl(struct sock *sk, int cmd, unsigned long arg) |
| 1165 | { |
| 1166 | switch (cmd) { |
| 1167 | case SIOCOUTQ: |
| 1168 | { |
| 1169 | int amount = sk_wmem_alloc_get(sk); |
| 1170 | |
| 1171 | return put_user(amount, (int __user *)arg); |
| 1172 | } |
| 1173 | |
| 1174 | case SIOCINQ: |
| 1175 | { |
| 1176 | unsigned int amount = first_packet_length(sk); |
| 1177 | |
| 1178 | if (amount) |
| 1179 | /* |
| 1180 | * We will only return the amount |
| 1181 | * of this packet since that is all |
| 1182 | * that will be read. |
| 1183 | */ |
| 1184 | amount -= sizeof(struct udphdr); |
| 1185 | |
| 1186 | return put_user(amount, (int __user *)arg); |
| 1187 | } |
| 1188 | |
| 1189 | default: |
| 1190 | return -ENOIOCTLCMD; |
| 1191 | } |
| 1192 | |
| 1193 | return 0; |
| 1194 | } |
| 1195 | EXPORT_SYMBOL(udp_ioctl); |
| 1196 | |
| 1197 | /* |
| 1198 | * This should be easy, if there is something there we |
| 1199 | * return it, otherwise we block. |
| 1200 | */ |
| 1201 | |
| 1202 | int udp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, |
| 1203 | size_t len, int noblock, int flags, int *addr_len) |
| 1204 | { |
| 1205 | struct inet_sock *inet = inet_sk(sk); |
| 1206 | struct sockaddr_in *sin = (struct sockaddr_in *)msg->msg_name; |
| 1207 | struct sk_buff *skb; |
| 1208 | unsigned int ulen, copied; |
| 1209 | int peeked, off = 0; |
| 1210 | int err; |
| 1211 | int is_udplite = IS_UDPLITE(sk); |
| 1212 | bool checksum_valid = false; |
| 1213 | bool slow; |
| 1214 | |
| 1215 | if (flags & MSG_ERRQUEUE) |
| 1216 | return ip_recv_error(sk, msg, len, addr_len); |
| 1217 | |
| 1218 | try_again: |
| 1219 | skb = __skb_recv_datagram(sk, flags | (noblock ? MSG_DONTWAIT : 0), |
| 1220 | &peeked, &off, &err); |
| 1221 | if (!skb) |
| 1222 | goto out; |
| 1223 | |
| 1224 | ulen = skb->len - sizeof(struct udphdr); |
| 1225 | copied = len; |
| 1226 | if (copied > ulen) |
| 1227 | copied = ulen; |
| 1228 | else if (copied < ulen) |
| 1229 | msg->msg_flags |= MSG_TRUNC; |
| 1230 | |
| 1231 | /* |
| 1232 | * If checksum is needed at all, try to do it while copying the |
| 1233 | * data. If the data is truncated, or if we only want a partial |
| 1234 | * coverage checksum (UDP-Lite), do it before the copy. |
| 1235 | */ |
| 1236 | |
| 1237 | if (copied < ulen || UDP_SKB_CB(skb)->partial_cov) { |
| 1238 | checksum_valid = !udp_lib_checksum_complete(skb); |
| 1239 | if (!checksum_valid) |
| 1240 | goto csum_copy_err; |
| 1241 | } |
| 1242 | |
| 1243 | if (checksum_valid || skb_csum_unnecessary(skb)) |
| 1244 | err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr), |
| 1245 | msg->msg_iov, copied); |
| 1246 | else { |
| 1247 | err = skb_copy_and_csum_datagram_iovec(skb, |
| 1248 | sizeof(struct udphdr), |
| 1249 | msg->msg_iov, copied); |
| 1250 | |
| 1251 | if (err == -EINVAL) |
| 1252 | goto csum_copy_err; |
| 1253 | } |
| 1254 | |
| 1255 | if (unlikely(err)) { |
| 1256 | trace_kfree_skb(skb, udp_recvmsg); |
| 1257 | if (!peeked) { |
| 1258 | atomic_inc(&sk->sk_drops); |
| 1259 | UDP_INC_STATS_USER(sock_net(sk), |
| 1260 | UDP_MIB_INERRORS, is_udplite); |
| 1261 | } |
| 1262 | goto out_free; |
| 1263 | } |
| 1264 | |
| 1265 | if (!peeked) |
| 1266 | UDP_INC_STATS_USER(sock_net(sk), |
| 1267 | UDP_MIB_INDATAGRAMS, is_udplite); |
| 1268 | |
| 1269 | sock_recv_ts_and_drops(msg, sk, skb); |
| 1270 | |
| 1271 | /* Copy the address. */ |
| 1272 | if (sin) { |
| 1273 | sin->sin_family = AF_INET; |
| 1274 | sin->sin_port = udp_hdr(skb)->source; |
| 1275 | sin->sin_addr.s_addr = ip_hdr(skb)->saddr; |
| 1276 | memset(sin->sin_zero, 0, sizeof(sin->sin_zero)); |
| 1277 | *addr_len = sizeof(*sin); |
| 1278 | } |
| 1279 | if (inet->cmsg_flags) |
| 1280 | ip_cmsg_recv(msg, skb); |
| 1281 | |
| 1282 | err = copied; |
| 1283 | if (flags & MSG_TRUNC) |
| 1284 | err = ulen; |
| 1285 | |
| 1286 | out_free: |
| 1287 | skb_free_datagram_locked(sk, skb); |
| 1288 | out: |
| 1289 | return err; |
| 1290 | |
| 1291 | csum_copy_err: |
| 1292 | slow = lock_sock_fast(sk); |
| 1293 | if (!skb_kill_datagram(sk, skb, flags)) { |
| 1294 | UDP_INC_STATS_USER(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite); |
| 1295 | UDP_INC_STATS_USER(sock_net(sk), UDP_MIB_INERRORS, is_udplite); |
| 1296 | } |
| 1297 | unlock_sock_fast(sk, slow); |
| 1298 | |
| 1299 | /* starting over for a new packet, but check if we need to yield */ |
| 1300 | cond_resched(); |
| 1301 | msg->msg_flags &= ~MSG_TRUNC; |
| 1302 | goto try_again; |
| 1303 | } |
| 1304 | |
| 1305 | |
| 1306 | int udp_disconnect(struct sock *sk, int flags) |
| 1307 | { |
| 1308 | struct inet_sock *inet = inet_sk(sk); |
| 1309 | /* |
| 1310 | * 1003.1g - break association. |
| 1311 | */ |
| 1312 | |
| 1313 | sk->sk_state = TCP_CLOSE; |
| 1314 | inet->inet_daddr = 0; |
| 1315 | inet->inet_dport = 0; |
| 1316 | sock_rps_reset_rxhash(sk); |
| 1317 | sk->sk_bound_dev_if = 0; |
| 1318 | if (!(sk->sk_userlocks & SOCK_BINDADDR_LOCK)) |
| 1319 | inet_reset_saddr(sk); |
| 1320 | |
| 1321 | if (!(sk->sk_userlocks & SOCK_BINDPORT_LOCK)) { |
| 1322 | sk->sk_prot->unhash(sk); |
| 1323 | inet->inet_sport = 0; |
| 1324 | } |
| 1325 | sk_dst_reset(sk); |
| 1326 | return 0; |
| 1327 | } |
| 1328 | EXPORT_SYMBOL(udp_disconnect); |
| 1329 | |
| 1330 | void udp_lib_unhash(struct sock *sk) |
| 1331 | { |
| 1332 | if (sk_hashed(sk)) { |
| 1333 | struct udp_table *udptable = sk->sk_prot->h.udp_table; |
| 1334 | struct udp_hslot *hslot, *hslot2; |
| 1335 | |
| 1336 | hslot = udp_hashslot(udptable, sock_net(sk), |
| 1337 | udp_sk(sk)->udp_port_hash); |
| 1338 | hslot2 = udp_hashslot2(udptable, udp_sk(sk)->udp_portaddr_hash); |
| 1339 | |
| 1340 | spin_lock_bh(&hslot->lock); |
| 1341 | if (sk_nulls_del_node_init_rcu(sk)) { |
| 1342 | hslot->count--; |
| 1343 | inet_sk(sk)->inet_num = 0; |
| 1344 | sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1); |
| 1345 | |
| 1346 | spin_lock(&hslot2->lock); |
| 1347 | hlist_nulls_del_init_rcu(&udp_sk(sk)->udp_portaddr_node); |
| 1348 | hslot2->count--; |
| 1349 | spin_unlock(&hslot2->lock); |
| 1350 | } |
| 1351 | spin_unlock_bh(&hslot->lock); |
| 1352 | } |
| 1353 | } |
| 1354 | EXPORT_SYMBOL(udp_lib_unhash); |
| 1355 | |
| 1356 | /* |
| 1357 | * inet_rcv_saddr was changed, we must rehash secondary hash |
| 1358 | */ |
| 1359 | void udp_lib_rehash(struct sock *sk, u16 newhash) |
| 1360 | { |
| 1361 | if (sk_hashed(sk)) { |
| 1362 | struct udp_table *udptable = sk->sk_prot->h.udp_table; |
| 1363 | struct udp_hslot *hslot, *hslot2, *nhslot2; |
| 1364 | |
| 1365 | hslot2 = udp_hashslot2(udptable, udp_sk(sk)->udp_portaddr_hash); |
| 1366 | nhslot2 = udp_hashslot2(udptable, newhash); |
| 1367 | udp_sk(sk)->udp_portaddr_hash = newhash; |
| 1368 | if (hslot2 != nhslot2) { |
| 1369 | hslot = udp_hashslot(udptable, sock_net(sk), |
| 1370 | udp_sk(sk)->udp_port_hash); |
| 1371 | /* we must lock primary chain too */ |
| 1372 | spin_lock_bh(&hslot->lock); |
| 1373 | |
| 1374 | spin_lock(&hslot2->lock); |
| 1375 | hlist_nulls_del_init_rcu(&udp_sk(sk)->udp_portaddr_node); |
| 1376 | hslot2->count--; |
| 1377 | spin_unlock(&hslot2->lock); |
| 1378 | |
| 1379 | spin_lock(&nhslot2->lock); |
| 1380 | hlist_nulls_add_head_rcu(&udp_sk(sk)->udp_portaddr_node, |
| 1381 | &nhslot2->head); |
| 1382 | nhslot2->count++; |
| 1383 | spin_unlock(&nhslot2->lock); |
| 1384 | |
| 1385 | spin_unlock_bh(&hslot->lock); |
| 1386 | } |
| 1387 | } |
| 1388 | } |
| 1389 | EXPORT_SYMBOL(udp_lib_rehash); |
| 1390 | |
| 1391 | static void udp_v4_rehash(struct sock *sk) |
| 1392 | { |
| 1393 | u16 new_hash = udp4_portaddr_hash(sock_net(sk), |
| 1394 | inet_sk(sk)->inet_rcv_saddr, |
| 1395 | inet_sk(sk)->inet_num); |
| 1396 | udp_lib_rehash(sk, new_hash); |
| 1397 | } |
| 1398 | |
| 1399 | static int __udp_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) |
| 1400 | { |
| 1401 | int rc; |
| 1402 | |
| 1403 | if (inet_sk(sk)->inet_daddr) |
| 1404 | sock_rps_save_rxhash(sk, skb); |
| 1405 | |
| 1406 | rc = sock_queue_rcv_skb(sk, skb); |
| 1407 | if (rc < 0) { |
| 1408 | int is_udplite = IS_UDPLITE(sk); |
| 1409 | |
| 1410 | /* Note that an ENOMEM error is charged twice */ |
| 1411 | if (rc == -ENOMEM) |
| 1412 | UDP_INC_STATS_BH(sock_net(sk), UDP_MIB_RCVBUFERRORS, |
| 1413 | is_udplite); |
| 1414 | UDP_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite); |
| 1415 | kfree_skb(skb); |
| 1416 | trace_udp_fail_queue_rcv_skb(rc, sk); |
| 1417 | return -1; |
| 1418 | } |
| 1419 | |
| 1420 | return 0; |
| 1421 | |
| 1422 | } |
| 1423 | |
| 1424 | static struct static_key udp_encap_needed __read_mostly; |
| 1425 | void udp_encap_enable(void) |
| 1426 | { |
| 1427 | if (!static_key_enabled(&udp_encap_needed)) |
| 1428 | static_key_slow_inc(&udp_encap_needed); |
| 1429 | } |
| 1430 | EXPORT_SYMBOL(udp_encap_enable); |
| 1431 | |
| 1432 | /* returns: |
| 1433 | * -1: error |
| 1434 | * 0: success |
| 1435 | * >0: "udp encap" protocol resubmission |
| 1436 | * |
| 1437 | * Note that in the success and error cases, the skb is assumed to |
| 1438 | * have either been requeued or freed. |
| 1439 | */ |
| 1440 | int udp_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) |
| 1441 | { |
| 1442 | struct udp_sock *up = udp_sk(sk); |
| 1443 | int rc; |
| 1444 | int is_udplite = IS_UDPLITE(sk); |
| 1445 | |
| 1446 | /* |
| 1447 | * Charge it to the socket, dropping if the queue is full. |
| 1448 | */ |
| 1449 | if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) |
| 1450 | goto drop; |
| 1451 | nf_reset(skb); |
| 1452 | |
| 1453 | if (static_key_false(&udp_encap_needed) && up->encap_type) { |
| 1454 | int (*encap_rcv)(struct sock *sk, struct sk_buff *skb); |
| 1455 | |
| 1456 | /* |
| 1457 | * This is an encapsulation socket so pass the skb to |
| 1458 | * the socket's udp_encap_rcv() hook. Otherwise, just |
| 1459 | * fall through and pass this up the UDP socket. |
| 1460 | * up->encap_rcv() returns the following value: |
| 1461 | * =0 if skb was successfully passed to the encap |
| 1462 | * handler or was discarded by it. |
| 1463 | * >0 if skb should be passed on to UDP. |
| 1464 | * <0 if skb should be resubmitted as proto -N |
| 1465 | */ |
| 1466 | |
| 1467 | /* if we're overly short, let UDP handle it */ |
| 1468 | encap_rcv = ACCESS_ONCE(up->encap_rcv); |
| 1469 | if (skb->len > sizeof(struct udphdr) && encap_rcv != NULL) { |
| 1470 | int ret; |
| 1471 | |
| 1472 | ret = encap_rcv(sk, skb); |
| 1473 | if (ret <= 0) { |
| 1474 | UDP_INC_STATS_BH(sock_net(sk), |
| 1475 | UDP_MIB_INDATAGRAMS, |
| 1476 | is_udplite); |
| 1477 | return -ret; |
| 1478 | } |
| 1479 | } |
| 1480 | |
| 1481 | /* FALLTHROUGH -- it's a UDP Packet */ |
| 1482 | } |
| 1483 | |
| 1484 | /* |
| 1485 | * UDP-Lite specific tests, ignored on UDP sockets |
| 1486 | */ |
| 1487 | if ((is_udplite & UDPLITE_RECV_CC) && UDP_SKB_CB(skb)->partial_cov) { |
| 1488 | |
| 1489 | /* |
| 1490 | * MIB statistics other than incrementing the error count are |
| 1491 | * disabled for the following two types of errors: these depend |
| 1492 | * on the application settings, not on the functioning of the |
| 1493 | * protocol stack as such. |
| 1494 | * |
| 1495 | * RFC 3828 here recommends (sec 3.3): "There should also be a |
| 1496 | * way ... to ... at least let the receiving application block |
| 1497 | * delivery of packets with coverage values less than a value |
| 1498 | * provided by the application." |
| 1499 | */ |
| 1500 | if (up->pcrlen == 0) { /* full coverage was set */ |
| 1501 | LIMIT_NETDEBUG(KERN_WARNING "UDPLite: partial coverage %d while full coverage %d requested\n", |
| 1502 | UDP_SKB_CB(skb)->cscov, skb->len); |
| 1503 | goto drop; |
| 1504 | } |
| 1505 | /* The next case involves violating the min. coverage requested |
| 1506 | * by the receiver. This is subtle: if receiver wants x and x is |
| 1507 | * greater than the buffersize/MTU then receiver will complain |
| 1508 | * that it wants x while sender emits packets of smaller size y. |
| 1509 | * Therefore the above ...()->partial_cov statement is essential. |
| 1510 | */ |
| 1511 | if (UDP_SKB_CB(skb)->cscov < up->pcrlen) { |
| 1512 | LIMIT_NETDEBUG(KERN_WARNING "UDPLite: coverage %d too small, need min %d\n", |
| 1513 | UDP_SKB_CB(skb)->cscov, up->pcrlen); |
| 1514 | goto drop; |
| 1515 | } |
| 1516 | } |
| 1517 | |
| 1518 | if (rcu_access_pointer(sk->sk_filter) && |
| 1519 | udp_lib_checksum_complete(skb)) |
| 1520 | goto csum_error; |
| 1521 | |
| 1522 | |
| 1523 | if (sk_rcvqueues_full(sk, skb, sk->sk_rcvbuf)) |
| 1524 | goto drop; |
| 1525 | |
| 1526 | rc = 0; |
| 1527 | |
| 1528 | ipv4_pktinfo_prepare(skb); |
| 1529 | bh_lock_sock(sk); |
| 1530 | if (!sock_owned_by_user(sk)) |
| 1531 | rc = __udp_queue_rcv_skb(sk, skb); |
| 1532 | else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) { |
| 1533 | bh_unlock_sock(sk); |
| 1534 | goto drop; |
| 1535 | } |
| 1536 | bh_unlock_sock(sk); |
| 1537 | |
| 1538 | return rc; |
| 1539 | |
| 1540 | csum_error: |
| 1541 | UDP_INC_STATS_BH(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite); |
| 1542 | drop: |
| 1543 | UDP_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite); |
| 1544 | atomic_inc(&sk->sk_drops); |
| 1545 | kfree_skb(skb); |
| 1546 | return -1; |
| 1547 | } |
| 1548 | |
| 1549 | |
| 1550 | static void flush_stack(struct sock **stack, unsigned int count, |
| 1551 | struct sk_buff *skb, unsigned int final) |
| 1552 | { |
| 1553 | unsigned int i; |
| 1554 | struct sk_buff *skb1 = NULL; |
| 1555 | struct sock *sk; |
| 1556 | |
| 1557 | for (i = 0; i < count; i++) { |
| 1558 | sk = stack[i]; |
| 1559 | if (likely(skb1 == NULL)) |
| 1560 | skb1 = (i == final) ? skb : skb_clone(skb, GFP_ATOMIC); |
| 1561 | |
| 1562 | if (!skb1) { |
| 1563 | atomic_inc(&sk->sk_drops); |
| 1564 | UDP_INC_STATS_BH(sock_net(sk), UDP_MIB_RCVBUFERRORS, |
| 1565 | IS_UDPLITE(sk)); |
| 1566 | UDP_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, |
| 1567 | IS_UDPLITE(sk)); |
| 1568 | } |
| 1569 | |
| 1570 | if (skb1 && udp_queue_rcv_skb(sk, skb1) <= 0) |
| 1571 | skb1 = NULL; |
| 1572 | } |
| 1573 | if (unlikely(skb1)) |
| 1574 | kfree_skb(skb1); |
| 1575 | } |
| 1576 | |
| 1577 | /* |
| 1578 | * Multicasts and broadcasts go to each listener. |
| 1579 | * |
| 1580 | * Note: called only from the BH handler context. |
| 1581 | */ |
| 1582 | static int __udp4_lib_mcast_deliver(struct net *net, struct sk_buff *skb, |
| 1583 | struct udphdr *uh, |
| 1584 | __be32 saddr, __be32 daddr, |
| 1585 | struct udp_table *udptable) |
| 1586 | { |
| 1587 | struct sock *sk, *stack[256 / sizeof(struct sock *)]; |
| 1588 | struct udp_hslot *hslot = udp_hashslot(udptable, net, ntohs(uh->dest)); |
| 1589 | int dif; |
| 1590 | unsigned int i, count = 0; |
| 1591 | |
| 1592 | spin_lock(&hslot->lock); |
| 1593 | sk = sk_nulls_head(&hslot->head); |
| 1594 | dif = skb->dev->ifindex; |
| 1595 | sk = udp_v4_mcast_next(net, sk, uh->dest, daddr, uh->source, saddr, dif); |
| 1596 | while (sk) { |
| 1597 | stack[count++] = sk; |
| 1598 | sk = udp_v4_mcast_next(net, sk_nulls_next(sk), uh->dest, |
| 1599 | daddr, uh->source, saddr, dif); |
| 1600 | if (unlikely(count == ARRAY_SIZE(stack))) { |
| 1601 | if (!sk) |
| 1602 | break; |
| 1603 | flush_stack(stack, count, skb, ~0); |
| 1604 | count = 0; |
| 1605 | } |
| 1606 | } |
| 1607 | /* |
| 1608 | * before releasing chain lock, we must take a reference on sockets |
| 1609 | */ |
| 1610 | for (i = 0; i < count; i++) |
| 1611 | sock_hold(stack[i]); |
| 1612 | |
| 1613 | spin_unlock(&hslot->lock); |
| 1614 | |
| 1615 | /* |
| 1616 | * do the slow work with no lock held |
| 1617 | */ |
| 1618 | if (count) { |
| 1619 | flush_stack(stack, count, skb, count - 1); |
| 1620 | |
| 1621 | for (i = 0; i < count; i++) |
| 1622 | sock_put(stack[i]); |
| 1623 | } else { |
| 1624 | kfree_skb(skb); |
| 1625 | } |
| 1626 | return 0; |
| 1627 | } |
| 1628 | |
| 1629 | /* Initialize UDP checksum. If exited with zero value (success), |
| 1630 | * CHECKSUM_UNNECESSARY means, that no more checks are required. |
| 1631 | * Otherwise, csum completion requires chacksumming packet body, |
| 1632 | * including udp header and folding it to skb->csum. |
| 1633 | */ |
| 1634 | static inline int udp4_csum_init(struct sk_buff *skb, struct udphdr *uh, |
| 1635 | int proto) |
| 1636 | { |
| 1637 | const struct iphdr *iph; |
| 1638 | int err; |
| 1639 | |
| 1640 | UDP_SKB_CB(skb)->partial_cov = 0; |
| 1641 | UDP_SKB_CB(skb)->cscov = skb->len; |
| 1642 | |
| 1643 | if (proto == IPPROTO_UDPLITE) { |
| 1644 | err = udplite_checksum_init(skb, uh); |
| 1645 | if (err) |
| 1646 | return err; |
| 1647 | } |
| 1648 | |
| 1649 | iph = ip_hdr(skb); |
| 1650 | if (uh->check == 0) { |
| 1651 | skb->ip_summed = CHECKSUM_UNNECESSARY; |
| 1652 | } else if (skb->ip_summed == CHECKSUM_COMPLETE) { |
| 1653 | if (!csum_tcpudp_magic(iph->saddr, iph->daddr, skb->len, |
| 1654 | proto, skb->csum)) |
| 1655 | skb->ip_summed = CHECKSUM_UNNECESSARY; |
| 1656 | } |
| 1657 | if (!skb_csum_unnecessary(skb)) |
| 1658 | skb->csum = csum_tcpudp_nofold(iph->saddr, iph->daddr, |
| 1659 | skb->len, proto, 0); |
| 1660 | /* Probably, we should checksum udp header (it should be in cache |
| 1661 | * in any case) and data in tiny packets (< rx copybreak). |
| 1662 | */ |
| 1663 | |
| 1664 | return 0; |
| 1665 | } |
| 1666 | |
| 1667 | /* |
| 1668 | * All we need to do is get the socket, and then do a checksum. |
| 1669 | */ |
| 1670 | |
| 1671 | int __udp4_lib_rcv(struct sk_buff *skb, struct udp_table *udptable, |
| 1672 | int proto) |
| 1673 | { |
| 1674 | struct sock *sk; |
| 1675 | struct udphdr *uh; |
| 1676 | unsigned short ulen; |
| 1677 | struct rtable *rt = skb_rtable(skb); |
| 1678 | __be32 saddr, daddr; |
| 1679 | struct net *net = dev_net(skb->dev); |
| 1680 | |
| 1681 | /* |
| 1682 | * Validate the packet. |
| 1683 | */ |
| 1684 | if (!pskb_may_pull(skb, sizeof(struct udphdr))) |
| 1685 | goto drop; /* No space for header. */ |
| 1686 | |
| 1687 | uh = udp_hdr(skb); |
| 1688 | ulen = ntohs(uh->len); |
| 1689 | saddr = ip_hdr(skb)->saddr; |
| 1690 | daddr = ip_hdr(skb)->daddr; |
| 1691 | |
| 1692 | if (ulen > skb->len) |
| 1693 | goto short_packet; |
| 1694 | |
| 1695 | if (proto == IPPROTO_UDP) { |
| 1696 | /* UDP validates ulen. */ |
| 1697 | if (ulen < sizeof(*uh) || pskb_trim_rcsum(skb, ulen)) |
| 1698 | goto short_packet; |
| 1699 | uh = udp_hdr(skb); |
| 1700 | } |
| 1701 | |
| 1702 | if (udp4_csum_init(skb, uh, proto)) |
| 1703 | goto csum_error; |
| 1704 | |
| 1705 | if (rt->rt_flags & (RTCF_BROADCAST|RTCF_MULTICAST)) |
| 1706 | return __udp4_lib_mcast_deliver(net, skb, uh, |
| 1707 | saddr, daddr, udptable); |
| 1708 | |
| 1709 | sk = __udp4_lib_lookup_skb(skb, uh->source, uh->dest, udptable); |
| 1710 | |
| 1711 | if (sk != NULL) { |
| 1712 | int ret = udp_queue_rcv_skb(sk, skb); |
| 1713 | sock_put(sk); |
| 1714 | |
| 1715 | /* a return value > 0 means to resubmit the input, but |
| 1716 | * it wants the return to be -protocol, or 0 |
| 1717 | */ |
| 1718 | if (ret > 0) |
| 1719 | return -ret; |
| 1720 | return 0; |
| 1721 | } |
| 1722 | |
| 1723 | if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) |
| 1724 | goto drop; |
| 1725 | nf_reset(skb); |
| 1726 | |
| 1727 | /* No socket. Drop packet silently, if checksum is wrong */ |
| 1728 | if (udp_lib_checksum_complete(skb)) |
| 1729 | goto csum_error; |
| 1730 | |
| 1731 | UDP_INC_STATS_BH(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE); |
| 1732 | icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0); |
| 1733 | |
| 1734 | /* |
| 1735 | * Hmm. We got an UDP packet to a port to which we |
| 1736 | * don't wanna listen. Ignore it. |
| 1737 | */ |
| 1738 | kfree_skb(skb); |
| 1739 | return 0; |
| 1740 | |
| 1741 | short_packet: |
| 1742 | LIMIT_NETDEBUG(KERN_DEBUG "UDP%s: short packet: From %pI4:%u %d/%d to %pI4:%u\n", |
| 1743 | proto == IPPROTO_UDPLITE ? "Lite" : "", |
| 1744 | &saddr, ntohs(uh->source), |
| 1745 | ulen, skb->len, |
| 1746 | &daddr, ntohs(uh->dest)); |
| 1747 | goto drop; |
| 1748 | |
| 1749 | csum_error: |
| 1750 | /* |
| 1751 | * RFC1122: OK. Discards the bad packet silently (as far as |
| 1752 | * the network is concerned, anyway) as per 4.1.3.4 (MUST). |
| 1753 | */ |
| 1754 | LIMIT_NETDEBUG(KERN_DEBUG "UDP%s: bad checksum. From %pI4:%u to %pI4:%u ulen %d\n", |
| 1755 | proto == IPPROTO_UDPLITE ? "Lite" : "", |
| 1756 | &saddr, ntohs(uh->source), &daddr, ntohs(uh->dest), |
| 1757 | ulen); |
| 1758 | UDP_INC_STATS_BH(net, UDP_MIB_CSUMERRORS, proto == IPPROTO_UDPLITE); |
| 1759 | drop: |
| 1760 | UDP_INC_STATS_BH(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE); |
| 1761 | kfree_skb(skb); |
| 1762 | return 0; |
| 1763 | } |
| 1764 | |
| 1765 | int udp_rcv(struct sk_buff *skb) |
| 1766 | { |
| 1767 | return __udp4_lib_rcv(skb, &udp_table, IPPROTO_UDP); |
| 1768 | } |
| 1769 | |
| 1770 | void udp_destroy_sock(struct sock *sk) |
| 1771 | { |
| 1772 | struct udp_sock *up = udp_sk(sk); |
| 1773 | bool slow = lock_sock_fast(sk); |
| 1774 | udp_flush_pending_frames(sk); |
| 1775 | unlock_sock_fast(sk, slow); |
| 1776 | if (static_key_false(&udp_encap_needed) && up->encap_type) { |
| 1777 | void (*encap_destroy)(struct sock *sk); |
| 1778 | encap_destroy = ACCESS_ONCE(up->encap_destroy); |
| 1779 | if (encap_destroy) |
| 1780 | encap_destroy(sk); |
| 1781 | } |
| 1782 | } |
| 1783 | |
| 1784 | /* |
| 1785 | * Socket option code for UDP |
| 1786 | */ |
| 1787 | int udp_lib_setsockopt(struct sock *sk, int level, int optname, |
| 1788 | char __user *optval, unsigned int optlen, |
| 1789 | int (*push_pending_frames)(struct sock *)) |
| 1790 | { |
| 1791 | struct udp_sock *up = udp_sk(sk); |
| 1792 | int val; |
| 1793 | int err = 0; |
| 1794 | int is_udplite = IS_UDPLITE(sk); |
| 1795 | |
| 1796 | if (optlen < sizeof(int)) |
| 1797 | return -EINVAL; |
| 1798 | |
| 1799 | if (get_user(val, (int __user *)optval)) |
| 1800 | return -EFAULT; |
| 1801 | |
| 1802 | switch (optname) { |
| 1803 | case UDP_CORK: |
| 1804 | if (val != 0) { |
| 1805 | up->corkflag = 1; |
| 1806 | } else { |
| 1807 | up->corkflag = 0; |
| 1808 | lock_sock(sk); |
| 1809 | (*push_pending_frames)(sk); |
| 1810 | release_sock(sk); |
| 1811 | } |
| 1812 | break; |
| 1813 | |
| 1814 | case UDP_ENCAP: |
| 1815 | switch (val) { |
| 1816 | case 0: |
| 1817 | case UDP_ENCAP_ESPINUDP: |
| 1818 | case UDP_ENCAP_ESPINUDP_NON_IKE: |
| 1819 | up->encap_rcv = xfrm4_udp_encap_rcv; |
| 1820 | /* FALLTHROUGH */ |
| 1821 | case UDP_ENCAP_L2TPINUDP: |
| 1822 | up->encap_type = val; |
| 1823 | udp_encap_enable(); |
| 1824 | break; |
| 1825 | default: |
| 1826 | err = -ENOPROTOOPT; |
| 1827 | break; |
| 1828 | } |
| 1829 | break; |
| 1830 | |
| 1831 | /* |
| 1832 | * UDP-Lite's partial checksum coverage (RFC 3828). |
| 1833 | */ |
| 1834 | /* The sender sets actual checksum coverage length via this option. |
| 1835 | * The case coverage > packet length is handled by send module. */ |
| 1836 | case UDPLITE_SEND_CSCOV: |
| 1837 | if (!is_udplite) /* Disable the option on UDP sockets */ |
| 1838 | return -ENOPROTOOPT; |
| 1839 | if (val != 0 && val < 8) /* Illegal coverage: use default (8) */ |
| 1840 | val = 8; |
| 1841 | else if (val > USHRT_MAX) |
| 1842 | val = USHRT_MAX; |
| 1843 | up->pcslen = val; |
| 1844 | up->pcflag |= UDPLITE_SEND_CC; |
| 1845 | break; |
| 1846 | |
| 1847 | /* The receiver specifies a minimum checksum coverage value. To make |
| 1848 | * sense, this should be set to at least 8 (as done below). If zero is |
| 1849 | * used, this again means full checksum coverage. */ |
| 1850 | case UDPLITE_RECV_CSCOV: |
| 1851 | if (!is_udplite) /* Disable the option on UDP sockets */ |
| 1852 | return -ENOPROTOOPT; |
| 1853 | if (val != 0 && val < 8) /* Avoid silly minimal values. */ |
| 1854 | val = 8; |
| 1855 | else if (val > USHRT_MAX) |
| 1856 | val = USHRT_MAX; |
| 1857 | up->pcrlen = val; |
| 1858 | up->pcflag |= UDPLITE_RECV_CC; |
| 1859 | break; |
| 1860 | |
| 1861 | default: |
| 1862 | err = -ENOPROTOOPT; |
| 1863 | break; |
| 1864 | } |
| 1865 | |
| 1866 | return err; |
| 1867 | } |
| 1868 | EXPORT_SYMBOL(udp_lib_setsockopt); |
| 1869 | |
| 1870 | int udp_setsockopt(struct sock *sk, int level, int optname, |
| 1871 | char __user *optval, unsigned int optlen) |
| 1872 | { |
| 1873 | if (level == SOL_UDP || level == SOL_UDPLITE) |
| 1874 | return udp_lib_setsockopt(sk, level, optname, optval, optlen, |
| 1875 | udp_push_pending_frames); |
| 1876 | return ip_setsockopt(sk, level, optname, optval, optlen); |
| 1877 | } |
| 1878 | |
| 1879 | #ifdef CONFIG_COMPAT |
| 1880 | int compat_udp_setsockopt(struct sock *sk, int level, int optname, |
| 1881 | char __user *optval, unsigned int optlen) |
| 1882 | { |
| 1883 | if (level == SOL_UDP || level == SOL_UDPLITE) |
| 1884 | return udp_lib_setsockopt(sk, level, optname, optval, optlen, |
| 1885 | udp_push_pending_frames); |
| 1886 | return compat_ip_setsockopt(sk, level, optname, optval, optlen); |
| 1887 | } |
| 1888 | #endif |
| 1889 | |
| 1890 | int udp_lib_getsockopt(struct sock *sk, int level, int optname, |
| 1891 | char __user *optval, int __user *optlen) |
| 1892 | { |
| 1893 | struct udp_sock *up = udp_sk(sk); |
| 1894 | int val, len; |
| 1895 | |
| 1896 | if (get_user(len, optlen)) |
| 1897 | return -EFAULT; |
| 1898 | |
| 1899 | len = min_t(unsigned int, len, sizeof(int)); |
| 1900 | |
| 1901 | if (len < 0) |
| 1902 | return -EINVAL; |
| 1903 | |
| 1904 | switch (optname) { |
| 1905 | case UDP_CORK: |
| 1906 | val = up->corkflag; |
| 1907 | break; |
| 1908 | |
| 1909 | case UDP_ENCAP: |
| 1910 | val = up->encap_type; |
| 1911 | break; |
| 1912 | |
| 1913 | /* The following two cannot be changed on UDP sockets, the return is |
| 1914 | * always 0 (which corresponds to the full checksum coverage of UDP). */ |
| 1915 | case UDPLITE_SEND_CSCOV: |
| 1916 | val = up->pcslen; |
| 1917 | break; |
| 1918 | |
| 1919 | case UDPLITE_RECV_CSCOV: |
| 1920 | val = up->pcrlen; |
| 1921 | break; |
| 1922 | |
| 1923 | default: |
| 1924 | return -ENOPROTOOPT; |
| 1925 | } |
| 1926 | |
| 1927 | if (put_user(len, optlen)) |
| 1928 | return -EFAULT; |
| 1929 | if (copy_to_user(optval, &val, len)) |
| 1930 | return -EFAULT; |
| 1931 | return 0; |
| 1932 | } |
| 1933 | EXPORT_SYMBOL(udp_lib_getsockopt); |
| 1934 | |
| 1935 | int udp_getsockopt(struct sock *sk, int level, int optname, |
| 1936 | char __user *optval, int __user *optlen) |
| 1937 | { |
| 1938 | if (level == SOL_UDP || level == SOL_UDPLITE) |
| 1939 | return udp_lib_getsockopt(sk, level, optname, optval, optlen); |
| 1940 | return ip_getsockopt(sk, level, optname, optval, optlen); |
| 1941 | } |
| 1942 | |
| 1943 | #ifdef CONFIG_COMPAT |
| 1944 | int compat_udp_getsockopt(struct sock *sk, int level, int optname, |
| 1945 | char __user *optval, int __user *optlen) |
| 1946 | { |
| 1947 | if (level == SOL_UDP || level == SOL_UDPLITE) |
| 1948 | return udp_lib_getsockopt(sk, level, optname, optval, optlen); |
| 1949 | return compat_ip_getsockopt(sk, level, optname, optval, optlen); |
| 1950 | } |
| 1951 | #endif |
| 1952 | /** |
| 1953 | * udp_poll - wait for a UDP event. |
| 1954 | * @file - file struct |
| 1955 | * @sock - socket |
| 1956 | * @wait - poll table |
| 1957 | * |
| 1958 | * This is same as datagram poll, except for the special case of |
| 1959 | * blocking sockets. If application is using a blocking fd |
| 1960 | * and a packet with checksum error is in the queue; |
| 1961 | * then it could get return from select indicating data available |
| 1962 | * but then block when reading it. Add special case code |
| 1963 | * to work around these arguably broken applications. |
| 1964 | */ |
| 1965 | unsigned int udp_poll(struct file *file, struct socket *sock, poll_table *wait) |
| 1966 | { |
| 1967 | unsigned int mask = datagram_poll(file, sock, wait); |
| 1968 | struct sock *sk = sock->sk; |
| 1969 | |
| 1970 | /* Check for false positives due to checksum errors */ |
| 1971 | if ((mask & POLLRDNORM) && !(file->f_flags & O_NONBLOCK) && |
| 1972 | !(sk->sk_shutdown & RCV_SHUTDOWN) && !first_packet_length(sk)) |
| 1973 | mask &= ~(POLLIN | POLLRDNORM); |
| 1974 | |
| 1975 | return mask; |
| 1976 | |
| 1977 | } |
| 1978 | EXPORT_SYMBOL(udp_poll); |
| 1979 | |
| 1980 | struct proto udp_prot = { |
| 1981 | .name = "UDP", |
| 1982 | .owner = THIS_MODULE, |
| 1983 | .close = udp_lib_close, |
| 1984 | .connect = ip4_datagram_connect, |
| 1985 | .disconnect = udp_disconnect, |
| 1986 | .ioctl = udp_ioctl, |
| 1987 | .destroy = udp_destroy_sock, |
| 1988 | .setsockopt = udp_setsockopt, |
| 1989 | .getsockopt = udp_getsockopt, |
| 1990 | .sendmsg = udp_sendmsg, |
| 1991 | .recvmsg = udp_recvmsg, |
| 1992 | .sendpage = udp_sendpage, |
| 1993 | .backlog_rcv = __udp_queue_rcv_skb, |
| 1994 | .release_cb = ip4_datagram_release_cb, |
| 1995 | .hash = udp_lib_hash, |
| 1996 | .unhash = udp_lib_unhash, |
| 1997 | .rehash = udp_v4_rehash, |
| 1998 | .get_port = udp_v4_get_port, |
| 1999 | .memory_allocated = &udp_memory_allocated, |
| 2000 | .sysctl_mem = sysctl_udp_mem, |
| 2001 | .sysctl_wmem = &sysctl_udp_wmem_min, |
| 2002 | .sysctl_rmem = &sysctl_udp_rmem_min, |
| 2003 | .obj_size = sizeof(struct udp_sock), |
| 2004 | .slab_flags = SLAB_DESTROY_BY_RCU, |
| 2005 | .h.udp_table = &udp_table, |
| 2006 | #ifdef CONFIG_COMPAT |
| 2007 | .compat_setsockopt = compat_udp_setsockopt, |
| 2008 | .compat_getsockopt = compat_udp_getsockopt, |
| 2009 | #endif |
| 2010 | .clear_sk = sk_prot_clear_portaddr_nulls, |
| 2011 | }; |
| 2012 | EXPORT_SYMBOL(udp_prot); |
| 2013 | |
| 2014 | /* ------------------------------------------------------------------------ */ |
| 2015 | #ifdef CONFIG_PROC_FS |
| 2016 | |
| 2017 | static struct sock *udp_get_first(struct seq_file *seq, int start) |
| 2018 | { |
| 2019 | struct sock *sk; |
| 2020 | struct udp_iter_state *state = seq->private; |
| 2021 | struct net *net = seq_file_net(seq); |
| 2022 | |
| 2023 | for (state->bucket = start; state->bucket <= state->udp_table->mask; |
| 2024 | ++state->bucket) { |
| 2025 | struct hlist_nulls_node *node; |
| 2026 | struct udp_hslot *hslot = &state->udp_table->hash[state->bucket]; |
| 2027 | |
| 2028 | if (hlist_nulls_empty(&hslot->head)) |
| 2029 | continue; |
| 2030 | |
| 2031 | spin_lock_bh(&hslot->lock); |
| 2032 | sk_nulls_for_each(sk, node, &hslot->head) { |
| 2033 | if (!net_eq(sock_net(sk), net)) |
| 2034 | continue; |
| 2035 | if (sk->sk_family == state->family) |
| 2036 | goto found; |
| 2037 | } |
| 2038 | spin_unlock_bh(&hslot->lock); |
| 2039 | } |
| 2040 | sk = NULL; |
| 2041 | found: |
| 2042 | return sk; |
| 2043 | } |
| 2044 | |
| 2045 | static struct sock *udp_get_next(struct seq_file *seq, struct sock *sk) |
| 2046 | { |
| 2047 | struct udp_iter_state *state = seq->private; |
| 2048 | struct net *net = seq_file_net(seq); |
| 2049 | |
| 2050 | do { |
| 2051 | sk = sk_nulls_next(sk); |
| 2052 | } while (sk && (!net_eq(sock_net(sk), net) || sk->sk_family != state->family)); |
| 2053 | |
| 2054 | if (!sk) { |
| 2055 | if (state->bucket <= state->udp_table->mask) |
| 2056 | spin_unlock_bh(&state->udp_table->hash[state->bucket].lock); |
| 2057 | return udp_get_first(seq, state->bucket + 1); |
| 2058 | } |
| 2059 | return sk; |
| 2060 | } |
| 2061 | |
| 2062 | static struct sock *udp_get_idx(struct seq_file *seq, loff_t pos) |
| 2063 | { |
| 2064 | struct sock *sk = udp_get_first(seq, 0); |
| 2065 | |
| 2066 | if (sk) |
| 2067 | while (pos && (sk = udp_get_next(seq, sk)) != NULL) |
| 2068 | --pos; |
| 2069 | return pos ? NULL : sk; |
| 2070 | } |
| 2071 | |
| 2072 | static void *udp_seq_start(struct seq_file *seq, loff_t *pos) |
| 2073 | { |
| 2074 | struct udp_iter_state *state = seq->private; |
| 2075 | state->bucket = MAX_UDP_PORTS; |
| 2076 | |
| 2077 | return *pos ? udp_get_idx(seq, *pos-1) : SEQ_START_TOKEN; |
| 2078 | } |
| 2079 | |
| 2080 | static void *udp_seq_next(struct seq_file *seq, void *v, loff_t *pos) |
| 2081 | { |
| 2082 | struct sock *sk; |
| 2083 | |
| 2084 | if (v == SEQ_START_TOKEN) |
| 2085 | sk = udp_get_idx(seq, 0); |
| 2086 | else |
| 2087 | sk = udp_get_next(seq, v); |
| 2088 | |
| 2089 | ++*pos; |
| 2090 | return sk; |
| 2091 | } |
| 2092 | |
| 2093 | static void udp_seq_stop(struct seq_file *seq, void *v) |
| 2094 | { |
| 2095 | struct udp_iter_state *state = seq->private; |
| 2096 | |
| 2097 | if (state->bucket <= state->udp_table->mask) |
| 2098 | spin_unlock_bh(&state->udp_table->hash[state->bucket].lock); |
| 2099 | } |
| 2100 | |
| 2101 | int udp_seq_open(struct inode *inode, struct file *file) |
| 2102 | { |
| 2103 | struct udp_seq_afinfo *afinfo = PDE_DATA(inode); |
| 2104 | struct udp_iter_state *s; |
| 2105 | int err; |
| 2106 | |
| 2107 | err = seq_open_net(inode, file, &afinfo->seq_ops, |
| 2108 | sizeof(struct udp_iter_state)); |
| 2109 | if (err < 0) |
| 2110 | return err; |
| 2111 | |
| 2112 | s = ((struct seq_file *)file->private_data)->private; |
| 2113 | s->family = afinfo->family; |
| 2114 | s->udp_table = afinfo->udp_table; |
| 2115 | return err; |
| 2116 | } |
| 2117 | EXPORT_SYMBOL(udp_seq_open); |
| 2118 | |
| 2119 | /* ------------------------------------------------------------------------ */ |
| 2120 | int udp_proc_register(struct net *net, struct udp_seq_afinfo *afinfo) |
| 2121 | { |
| 2122 | struct proc_dir_entry *p; |
| 2123 | int rc = 0; |
| 2124 | |
| 2125 | afinfo->seq_ops.start = udp_seq_start; |
| 2126 | afinfo->seq_ops.next = udp_seq_next; |
| 2127 | afinfo->seq_ops.stop = udp_seq_stop; |
| 2128 | |
| 2129 | p = proc_create_data(afinfo->name, S_IRUGO, net->proc_net, |
| 2130 | afinfo->seq_fops, afinfo); |
| 2131 | if (!p) |
| 2132 | rc = -ENOMEM; |
| 2133 | return rc; |
| 2134 | } |
| 2135 | EXPORT_SYMBOL(udp_proc_register); |
| 2136 | |
| 2137 | void udp_proc_unregister(struct net *net, struct udp_seq_afinfo *afinfo) |
| 2138 | { |
| 2139 | remove_proc_entry(afinfo->name, net->proc_net); |
| 2140 | } |
| 2141 | EXPORT_SYMBOL(udp_proc_unregister); |
| 2142 | |
| 2143 | /* ------------------------------------------------------------------------ */ |
| 2144 | static void udp4_format_sock(struct sock *sp, struct seq_file *f, |
| 2145 | int bucket, int *len) |
| 2146 | { |
| 2147 | struct inet_sock *inet = inet_sk(sp); |
| 2148 | __be32 dest = inet->inet_daddr; |
| 2149 | __be32 src = inet->inet_rcv_saddr; |
| 2150 | __u16 destp = ntohs(inet->inet_dport); |
| 2151 | __u16 srcp = ntohs(inet->inet_sport); |
| 2152 | |
| 2153 | seq_printf(f, "%5d: %08X:%04X %08X:%04X" |
| 2154 | " %02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %pK %d%n", |
| 2155 | bucket, src, srcp, dest, destp, sp->sk_state, |
| 2156 | sk_wmem_alloc_get(sp), |
| 2157 | sk_rmem_alloc_get(sp), |
| 2158 | 0, 0L, 0, |
| 2159 | from_kuid_munged(seq_user_ns(f), sock_i_uid(sp)), |
| 2160 | 0, sock_i_ino(sp), |
| 2161 | atomic_read(&sp->sk_refcnt), sp, |
| 2162 | atomic_read(&sp->sk_drops), len); |
| 2163 | } |
| 2164 | |
| 2165 | int udp4_seq_show(struct seq_file *seq, void *v) |
| 2166 | { |
| 2167 | if (v == SEQ_START_TOKEN) |
| 2168 | seq_printf(seq, "%-127s\n", |
| 2169 | " sl local_address rem_address st tx_queue " |
| 2170 | "rx_queue tr tm->when retrnsmt uid timeout " |
| 2171 | "inode ref pointer drops"); |
| 2172 | else { |
| 2173 | struct udp_iter_state *state = seq->private; |
| 2174 | int len; |
| 2175 | |
| 2176 | udp4_format_sock(v, seq, state->bucket, &len); |
| 2177 | seq_printf(seq, "%*s\n", 127 - len, ""); |
| 2178 | } |
| 2179 | return 0; |
| 2180 | } |
| 2181 | |
| 2182 | static const struct file_operations udp_afinfo_seq_fops = { |
| 2183 | .owner = THIS_MODULE, |
| 2184 | .open = udp_seq_open, |
| 2185 | .read = seq_read, |
| 2186 | .llseek = seq_lseek, |
| 2187 | .release = seq_release_net |
| 2188 | }; |
| 2189 | |
| 2190 | /* ------------------------------------------------------------------------ */ |
| 2191 | static struct udp_seq_afinfo udp4_seq_afinfo = { |
| 2192 | .name = "udp", |
| 2193 | .family = AF_INET, |
| 2194 | .udp_table = &udp_table, |
| 2195 | .seq_fops = &udp_afinfo_seq_fops, |
| 2196 | .seq_ops = { |
| 2197 | .show = udp4_seq_show, |
| 2198 | }, |
| 2199 | }; |
| 2200 | |
| 2201 | static int __net_init udp4_proc_init_net(struct net *net) |
| 2202 | { |
| 2203 | return udp_proc_register(net, &udp4_seq_afinfo); |
| 2204 | } |
| 2205 | |
| 2206 | static void __net_exit udp4_proc_exit_net(struct net *net) |
| 2207 | { |
| 2208 | udp_proc_unregister(net, &udp4_seq_afinfo); |
| 2209 | } |
| 2210 | |
| 2211 | static struct pernet_operations udp4_net_ops = { |
| 2212 | .init = udp4_proc_init_net, |
| 2213 | .exit = udp4_proc_exit_net, |
| 2214 | }; |
| 2215 | |
| 2216 | int __init udp4_proc_init(void) |
| 2217 | { |
| 2218 | return register_pernet_subsys(&udp4_net_ops); |
| 2219 | } |
| 2220 | |
| 2221 | void udp4_proc_exit(void) |
| 2222 | { |
| 2223 | unregister_pernet_subsys(&udp4_net_ops); |
| 2224 | } |
| 2225 | #endif /* CONFIG_PROC_FS */ |
| 2226 | |
| 2227 | static __initdata unsigned long uhash_entries; |
| 2228 | static int __init set_uhash_entries(char *str) |
| 2229 | { |
| 2230 | ssize_t ret; |
| 2231 | |
| 2232 | if (!str) |
| 2233 | return 0; |
| 2234 | |
| 2235 | ret = kstrtoul(str, 0, &uhash_entries); |
| 2236 | if (ret) |
| 2237 | return 0; |
| 2238 | |
| 2239 | if (uhash_entries && uhash_entries < UDP_HTABLE_SIZE_MIN) |
| 2240 | uhash_entries = UDP_HTABLE_SIZE_MIN; |
| 2241 | return 1; |
| 2242 | } |
| 2243 | __setup("uhash_entries=", set_uhash_entries); |
| 2244 | |
| 2245 | void __init udp_table_init(struct udp_table *table, const char *name) |
| 2246 | { |
| 2247 | unsigned int i; |
| 2248 | |
| 2249 | table->hash = alloc_large_system_hash(name, |
| 2250 | 2 * sizeof(struct udp_hslot), |
| 2251 | uhash_entries, |
| 2252 | 21, /* one slot per 2 MB */ |
| 2253 | 0, |
| 2254 | &table->log, |
| 2255 | &table->mask, |
| 2256 | UDP_HTABLE_SIZE_MIN, |
| 2257 | 64 * 1024); |
| 2258 | |
| 2259 | table->hash2 = table->hash + (table->mask + 1); |
| 2260 | for (i = 0; i <= table->mask; i++) { |
| 2261 | INIT_HLIST_NULLS_HEAD(&table->hash[i].head, i); |
| 2262 | table->hash[i].count = 0; |
| 2263 | spin_lock_init(&table->hash[i].lock); |
| 2264 | } |
| 2265 | for (i = 0; i <= table->mask; i++) { |
| 2266 | INIT_HLIST_NULLS_HEAD(&table->hash2[i].head, i); |
| 2267 | table->hash2[i].count = 0; |
| 2268 | spin_lock_init(&table->hash2[i].lock); |
| 2269 | } |
| 2270 | } |
| 2271 | |
| 2272 | void __init udp_init(void) |
| 2273 | { |
| 2274 | unsigned long limit; |
| 2275 | |
| 2276 | udp_table_init(&udp_table, "UDP"); |
| 2277 | limit = nr_free_buffer_pages() / 8; |
| 2278 | limit = max(limit, 128UL); |
| 2279 | sysctl_udp_mem[0] = limit / 4 * 3; |
| 2280 | sysctl_udp_mem[1] = limit; |
| 2281 | sysctl_udp_mem[2] = sysctl_udp_mem[0] * 2; |
| 2282 | |
| 2283 | sysctl_udp_rmem_min = SK_MEM_QUANTUM; |
| 2284 | sysctl_udp_wmem_min = SK_MEM_QUANTUM; |
| 2285 | } |
| 2286 | |
| 2287 | int udp4_ufo_send_check(struct sk_buff *skb) |
| 2288 | { |
| 2289 | if (!pskb_may_pull(skb, sizeof(struct udphdr))) |
| 2290 | return -EINVAL; |
| 2291 | |
| 2292 | if (likely(!skb->encapsulation)) { |
| 2293 | const struct iphdr *iph; |
| 2294 | struct udphdr *uh; |
| 2295 | |
| 2296 | iph = ip_hdr(skb); |
| 2297 | uh = udp_hdr(skb); |
| 2298 | |
| 2299 | uh->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr, skb->len, |
| 2300 | IPPROTO_UDP, 0); |
| 2301 | skb->csum_start = skb_transport_header(skb) - skb->head; |
| 2302 | skb->csum_offset = offsetof(struct udphdr, check); |
| 2303 | skb->ip_summed = CHECKSUM_PARTIAL; |
| 2304 | } |
| 2305 | return 0; |
| 2306 | } |
| 2307 | |
| 2308 | static struct sk_buff *skb_udp_tunnel_segment(struct sk_buff *skb, |
| 2309 | netdev_features_t features) |
| 2310 | { |
| 2311 | struct sk_buff *segs = ERR_PTR(-EINVAL); |
| 2312 | int mac_len = skb->mac_len; |
| 2313 | int tnl_hlen = skb_inner_mac_header(skb) - skb_transport_header(skb); |
| 2314 | __be16 protocol = skb->protocol; |
| 2315 | netdev_features_t enc_features; |
| 2316 | int outer_hlen; |
| 2317 | |
| 2318 | if (unlikely(!pskb_may_pull(skb, tnl_hlen))) |
| 2319 | goto out; |
| 2320 | |
| 2321 | skb->encapsulation = 0; |
| 2322 | __skb_pull(skb, tnl_hlen); |
| 2323 | skb_reset_mac_header(skb); |
| 2324 | skb_set_network_header(skb, skb_inner_network_offset(skb)); |
| 2325 | skb->mac_len = skb_inner_network_offset(skb); |
| 2326 | skb->protocol = htons(ETH_P_TEB); |
| 2327 | |
| 2328 | /* segment inner packet. */ |
| 2329 | enc_features = skb->dev->hw_enc_features & netif_skb_features(skb); |
| 2330 | segs = skb_mac_gso_segment(skb, enc_features); |
| 2331 | if (!segs || IS_ERR(segs)) |
| 2332 | goto out; |
| 2333 | |
| 2334 | outer_hlen = skb_tnl_header_len(skb); |
| 2335 | skb = segs; |
| 2336 | do { |
| 2337 | struct udphdr *uh; |
| 2338 | int udp_offset = outer_hlen - tnl_hlen; |
| 2339 | |
| 2340 | skb->mac_len = mac_len; |
| 2341 | |
| 2342 | skb_push(skb, outer_hlen); |
| 2343 | skb_reset_mac_header(skb); |
| 2344 | skb_set_network_header(skb, mac_len); |
| 2345 | skb_set_transport_header(skb, udp_offset); |
| 2346 | uh = udp_hdr(skb); |
| 2347 | uh->len = htons(skb->len - udp_offset); |
| 2348 | |
| 2349 | /* csum segment if tunnel sets skb with csum. */ |
| 2350 | if (unlikely(uh->check)) { |
| 2351 | struct iphdr *iph = ip_hdr(skb); |
| 2352 | |
| 2353 | uh->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr, |
| 2354 | skb->len - udp_offset, |
| 2355 | IPPROTO_UDP, 0); |
| 2356 | uh->check = csum_fold(skb_checksum(skb, udp_offset, |
| 2357 | skb->len - udp_offset, 0)); |
| 2358 | if (uh->check == 0) |
| 2359 | uh->check = CSUM_MANGLED_0; |
| 2360 | |
| 2361 | } |
| 2362 | skb->ip_summed = CHECKSUM_NONE; |
| 2363 | skb->protocol = protocol; |
| 2364 | } while ((skb = skb->next)); |
| 2365 | out: |
| 2366 | return segs; |
| 2367 | } |
| 2368 | |
| 2369 | struct sk_buff *udp4_ufo_fragment(struct sk_buff *skb, |
| 2370 | netdev_features_t features) |
| 2371 | { |
| 2372 | struct sk_buff *segs = ERR_PTR(-EINVAL); |
| 2373 | unsigned int mss; |
| 2374 | mss = skb_shinfo(skb)->gso_size; |
| 2375 | if (unlikely(skb->len <= mss)) |
| 2376 | goto out; |
| 2377 | |
| 2378 | if (skb_gso_ok(skb, features | NETIF_F_GSO_ROBUST)) { |
| 2379 | /* Packet is from an untrusted source, reset gso_segs. */ |
| 2380 | int type = skb_shinfo(skb)->gso_type; |
| 2381 | |
| 2382 | if (unlikely(type & ~(SKB_GSO_UDP | SKB_GSO_DODGY | |
| 2383 | SKB_GSO_UDP_TUNNEL | |
| 2384 | SKB_GSO_GRE) || |
| 2385 | !(type & (SKB_GSO_UDP)))) |
| 2386 | goto out; |
| 2387 | |
| 2388 | skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(skb->len, mss); |
| 2389 | |
| 2390 | segs = NULL; |
| 2391 | goto out; |
| 2392 | } |
| 2393 | |
| 2394 | /* Fragment the skb. IP headers of the fragments are updated in |
| 2395 | * inet_gso_segment() |
| 2396 | */ |
| 2397 | if (skb->encapsulation && skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL) |
| 2398 | segs = skb_udp_tunnel_segment(skb, features); |
| 2399 | else { |
| 2400 | int offset; |
| 2401 | __wsum csum; |
| 2402 | |
| 2403 | /* Do software UFO. Complete and fill in the UDP checksum as |
| 2404 | * HW cannot do checksum of UDP packets sent as multiple |
| 2405 | * IP fragments. |
| 2406 | */ |
| 2407 | offset = skb_checksum_start_offset(skb); |
| 2408 | csum = skb_checksum(skb, offset, skb->len - offset, 0); |
| 2409 | offset += skb->csum_offset; |
| 2410 | *(__sum16 *)(skb->data + offset) = csum_fold(csum); |
| 2411 | skb->ip_summed = CHECKSUM_NONE; |
| 2412 | |
| 2413 | segs = skb_segment(skb, features); |
| 2414 | } |
| 2415 | out: |
| 2416 | return segs; |
| 2417 | } |