blob: acdc9be833ccf968bc4343ee06be85c46d300719 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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 *
Jesper Juhl02c30a82005-05-05 16:16:16 -07008 * Authors: Ross Biro
Linus Torvalds1da177e2005-04-16 15:20:36 -07009 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
10 * Arnt Gulbrandsen, <agulbra@nvg.unit.no>
Alan Cox113aa832008-10-13 19:01:08 -070011 * Alan Cox, <alan@lxorguk.ukuu.org.uk>
Linus Torvalds1da177e2005-04-16 15:20:36 -070012 * 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
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +090021 * Alan Cox : Tidied select() semantics.
22 * Alan Cox : udp_err() fixed properly, also now
Linus Torvalds1da177e2005-04-16 15:20:36 -070023 * 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
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +090057 * for connect.
Linus Torvalds1da177e2005-04-16 15:20:36 -070058 * 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
James Chapman342f0232007-06-27 15:37:46 -070071 * James Chapman : Add L2TP encapsulation type.
Linus Torvalds1da177e2005-04-16 15:20:36 -070072 *
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 */
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +090079
Linus Torvalds1da177e2005-04-16 15:20:36 -070080#include <asm/system.h>
81#include <asm/uaccess.h>
82#include <asm/ioctls.h>
Hideo Aoki95766ff2007-12-31 00:29:24 -080083#include <linux/bootmem.h>
Eric Dumazet8203efb2008-10-29 02:32:32 -070084#include <linux/highmem.h>
85#include <linux/swap.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070086#include <linux/types.h>
87#include <linux/fcntl.h>
88#include <linux/module.h>
89#include <linux/socket.h>
90#include <linux/sockios.h>
Arnaldo Carvalho de Melo14c85022005-12-27 02:43:12 -020091#include <linux/igmp.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070092#include <linux/in.h>
93#include <linux/errno.h>
94#include <linux/timer.h>
95#include <linux/mm.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070096#include <linux/inet.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070097#include <linux/netdevice.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090098#include <linux/slab.h>
Arnaldo Carvalho de Meloc752f072005-08-09 20:08:28 -070099#include <net/tcp_states.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700100#include <linux/skbuff.h>
101#include <linux/proc_fs.h>
102#include <linux/seq_file.h>
Eric W. Biederman457c4cb2007-09-12 12:01:34 +0200103#include <net/net_namespace.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700104#include <net/icmp.h>
105#include <net/route.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700106#include <net/checksum.h>
107#include <net/xfrm.h>
Gerrit Renkerba4e58e2006-11-27 11:10:57 -0800108#include "udp_impl.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700109
Eric Dumazetf86dcc52009-10-07 00:37:59 +0000110struct udp_table udp_table __read_mostly;
Eric Dumazet645ca702008-10-29 01:41:45 -0700111EXPORT_SYMBOL(udp_table);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700112
Hideo Aoki95766ff2007-12-31 00:29:24 -0800113int sysctl_udp_mem[3] __read_mostly;
Hideo Aoki95766ff2007-12-31 00:29:24 -0800114EXPORT_SYMBOL(sysctl_udp_mem);
Eric Dumazetc482c562009-07-17 00:26:32 +0000115
116int sysctl_udp_rmem_min __read_mostly;
Hideo Aoki95766ff2007-12-31 00:29:24 -0800117EXPORT_SYMBOL(sysctl_udp_rmem_min);
Eric Dumazetc482c562009-07-17 00:26:32 +0000118
119int sysctl_udp_wmem_min __read_mostly;
Hideo Aoki95766ff2007-12-31 00:29:24 -0800120EXPORT_SYMBOL(sysctl_udp_wmem_min);
121
122atomic_t udp_memory_allocated;
123EXPORT_SYMBOL(udp_memory_allocated);
124
Eric Dumazetf86dcc52009-10-07 00:37:59 +0000125#define MAX_UDP_PORTS 65536
126#define PORTS_PER_CHAIN (MAX_UDP_PORTS / UDP_HTABLE_SIZE_MIN)
Eric Dumazet98322f22009-01-26 21:35:35 -0800127
Eric Dumazetf24d43c2008-10-09 14:51:27 -0700128static int udp_lib_lport_inuse(struct net *net, __u16 num,
Eric Dumazet645ca702008-10-29 01:41:45 -0700129 const struct udp_hslot *hslot,
Eric Dumazet98322f22009-01-26 21:35:35 -0800130 unsigned long *bitmap,
Eric Dumazetf24d43c2008-10-09 14:51:27 -0700131 struct sock *sk,
132 int (*saddr_comp)(const struct sock *sk1,
Eric Dumazetf86dcc52009-10-07 00:37:59 +0000133 const struct sock *sk2),
134 unsigned int log)
Gerrit Renker25030a72006-08-26 20:06:05 -0700135{
Eric Dumazetf24d43c2008-10-09 14:51:27 -0700136 struct sock *sk2;
Eric Dumazet88ab1932008-11-16 19:39:21 -0800137 struct hlist_nulls_node *node;
Gerrit Renker25030a72006-08-26 20:06:05 -0700138
Eric Dumazet88ab1932008-11-16 19:39:21 -0800139 sk_nulls_for_each(sk2, node, &hslot->head)
Joe Perches9d4fb272009-11-23 10:41:23 -0800140 if (net_eq(sock_net(sk2), net) &&
141 sk2 != sk &&
Eric Dumazetd4cada42009-11-08 10:17:30 +0000142 (bitmap || udp_sk(sk2)->udp_port_hash == num) &&
Joe Perches9d4fb272009-11-23 10:41:23 -0800143 (!sk2->sk_reuse || !sk->sk_reuse) &&
144 (!sk2->sk_bound_dev_if || !sk->sk_bound_dev_if ||
145 sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
Eric Dumazet98322f22009-01-26 21:35:35 -0800146 (*saddr_comp)(sk, sk2)) {
147 if (bitmap)
Eric Dumazetd4cada42009-11-08 10:17:30 +0000148 __set_bit(udp_sk(sk2)->udp_port_hash >> log,
149 bitmap);
Eric Dumazet98322f22009-01-26 21:35:35 -0800150 else
151 return 1;
152 }
Gerrit Renker25030a72006-08-26 20:06:05 -0700153 return 0;
154}
155
Eric Dumazet30fff922009-11-09 05:26:33 +0000156/*
157 * Note: we still hold spinlock of primary hash chain, so no other writer
158 * can insert/delete a socket with local_port == num
159 */
160static int udp_lib_lport_inuse2(struct net *net, __u16 num,
161 struct udp_hslot *hslot2,
162 struct sock *sk,
163 int (*saddr_comp)(const struct sock *sk1,
164 const struct sock *sk2))
165{
166 struct sock *sk2;
167 struct hlist_nulls_node *node;
168 int res = 0;
169
170 spin_lock(&hslot2->lock);
171 udp_portaddr_for_each_entry(sk2, node, &hslot2->head)
Joe Perches9d4fb272009-11-23 10:41:23 -0800172 if (net_eq(sock_net(sk2), net) &&
173 sk2 != sk &&
174 (udp_sk(sk2)->udp_port_hash == num) &&
175 (!sk2->sk_reuse || !sk->sk_reuse) &&
176 (!sk2->sk_bound_dev_if || !sk->sk_bound_dev_if ||
177 sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
Eric Dumazet30fff922009-11-09 05:26:33 +0000178 (*saddr_comp)(sk, sk2)) {
179 res = 1;
180 break;
181 }
182 spin_unlock(&hslot2->lock);
183 return res;
184}
185
Gerrit Renker25030a72006-08-26 20:06:05 -0700186/**
Pavel Emelyanov6ba5a3c2008-03-22 16:51:21 -0700187 * udp_lib_get_port - UDP/-Lite port lookup for IPv4 and IPv6
Gerrit Renker25030a72006-08-26 20:06:05 -0700188 *
189 * @sk: socket struct in question
190 * @snum: port number to look up
David S. Millerdf2bc452007-06-05 15:18:43 -0700191 * @saddr_comp: AF-dependent comparison of bound local IP addresses
Eric Dumazet30fff922009-11-09 05:26:33 +0000192 * @hash2_nulladdr: AF-dependant hash value in secondary hash chains,
193 * with NULL address
Gerrit Renker25030a72006-08-26 20:06:05 -0700194 */
Pavel Emelyanov6ba5a3c2008-03-22 16:51:21 -0700195int udp_lib_get_port(struct sock *sk, unsigned short snum,
David S. Millerdf2bc452007-06-05 15:18:43 -0700196 int (*saddr_comp)(const struct sock *sk1,
Eric Dumazet30fff922009-11-09 05:26:33 +0000197 const struct sock *sk2),
198 unsigned int hash2_nulladdr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700199{
Eric Dumazet512615b2009-11-08 10:17:58 +0000200 struct udp_hslot *hslot, *hslot2;
Eric Dumazet645ca702008-10-29 01:41:45 -0700201 struct udp_table *udptable = sk->sk_prot->h.udp_table;
Gerrit Renker25030a72006-08-26 20:06:05 -0700202 int error = 1;
YOSHIFUJI Hideaki3b1e0a62008-03-26 02:26:21 +0900203 struct net *net = sock_net(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700204
Stephen Hemminger32c1da72007-08-24 23:09:41 -0700205 if (!snum) {
Eric Dumazet9088c562008-10-08 11:44:17 -0700206 int low, high, remaining;
207 unsigned rand;
Eric Dumazet98322f22009-01-26 21:35:35 -0800208 unsigned short first, last;
209 DECLARE_BITMAP(bitmap, PORTS_PER_CHAIN);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700210
Stephen Hemminger227b60f2007-10-10 17:30:46 -0700211 inet_get_local_port_range(&low, &high);
Anton Arapova25de532007-10-18 22:00:17 -0700212 remaining = (high - low) + 1;
Stephen Hemminger227b60f2007-10-10 17:30:46 -0700213
Eric Dumazet9088c562008-10-08 11:44:17 -0700214 rand = net_random();
Eric Dumazet98322f22009-01-26 21:35:35 -0800215 first = (((u64)rand * remaining) >> 32) + low;
216 /*
217 * force rand to be an odd multiple of UDP_HTABLE_SIZE
218 */
Eric Dumazetf86dcc52009-10-07 00:37:59 +0000219 rand = (rand | 1) * (udptable->mask + 1);
Eric Dumazet5781b232009-12-13 19:32:39 -0800220 last = first + udptable->mask + 1;
221 do {
Eric Dumazetf86dcc52009-10-07 00:37:59 +0000222 hslot = udp_hashslot(udptable, net, first);
Eric Dumazet98322f22009-01-26 21:35:35 -0800223 bitmap_zero(bitmap, PORTS_PER_CHAIN);
Eric Dumazet645ca702008-10-29 01:41:45 -0700224 spin_lock_bh(&hslot->lock);
Eric Dumazet98322f22009-01-26 21:35:35 -0800225 udp_lib_lport_inuse(net, snum, hslot, bitmap, sk,
Eric Dumazetf86dcc52009-10-07 00:37:59 +0000226 saddr_comp, udptable->log);
Eric Dumazet98322f22009-01-26 21:35:35 -0800227
228 snum = first;
229 /*
230 * Iterate on all possible values of snum for this hash.
231 * Using steps of an odd multiple of UDP_HTABLE_SIZE
232 * give us randomization and full range coverage.
233 */
Eric Dumazet9088c562008-10-08 11:44:17 -0700234 do {
Eric Dumazet98322f22009-01-26 21:35:35 -0800235 if (low <= snum && snum <= high &&
Amerigo Wange3826f12010-05-05 00:27:06 +0000236 !test_bit(snum >> udptable->log, bitmap) &&
237 !inet_is_reserved_local_port(snum))
Eric Dumazet98322f22009-01-26 21:35:35 -0800238 goto found;
239 snum += rand;
240 } while (snum != first);
241 spin_unlock_bh(&hslot->lock);
Eric Dumazet5781b232009-12-13 19:32:39 -0800242 } while (++first != last);
Eric Dumazet98322f22009-01-26 21:35:35 -0800243 goto fail;
Eric Dumazet645ca702008-10-29 01:41:45 -0700244 } else {
Eric Dumazetf86dcc52009-10-07 00:37:59 +0000245 hslot = udp_hashslot(udptable, net, snum);
Eric Dumazet645ca702008-10-29 01:41:45 -0700246 spin_lock_bh(&hslot->lock);
Eric Dumazet30fff922009-11-09 05:26:33 +0000247 if (hslot->count > 10) {
248 int exist;
249 unsigned int slot2 = udp_sk(sk)->udp_portaddr_hash ^ snum;
250
251 slot2 &= udptable->mask;
252 hash2_nulladdr &= udptable->mask;
253
254 hslot2 = udp_hashslot2(udptable, slot2);
255 if (hslot->count < hslot2->count)
256 goto scan_primary_hash;
257
258 exist = udp_lib_lport_inuse2(net, snum, hslot2,
259 sk, saddr_comp);
260 if (!exist && (hash2_nulladdr != slot2)) {
261 hslot2 = udp_hashslot2(udptable, hash2_nulladdr);
262 exist = udp_lib_lport_inuse2(net, snum, hslot2,
263 sk, saddr_comp);
264 }
265 if (exist)
266 goto fail_unlock;
267 else
268 goto found;
269 }
270scan_primary_hash:
Eric Dumazetf86dcc52009-10-07 00:37:59 +0000271 if (udp_lib_lport_inuse(net, snum, hslot, NULL, sk,
272 saddr_comp, 0))
Eric Dumazet645ca702008-10-29 01:41:45 -0700273 goto fail_unlock;
274 }
Eric Dumazet98322f22009-01-26 21:35:35 -0800275found:
Eric Dumazetc720c7e2009-10-15 06:30:45 +0000276 inet_sk(sk)->inet_num = snum;
Eric Dumazetd4cada42009-11-08 10:17:30 +0000277 udp_sk(sk)->udp_port_hash = snum;
278 udp_sk(sk)->udp_portaddr_hash ^= snum;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279 if (sk_unhashed(sk)) {
Eric Dumazet88ab1932008-11-16 19:39:21 -0800280 sk_nulls_add_node_rcu(sk, &hslot->head);
Eric Dumazetfdcc8aa92009-11-08 10:17:05 +0000281 hslot->count++;
Pavel Emelyanovc29a0bc2008-03-31 19:41:46 -0700282 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
Eric Dumazet512615b2009-11-08 10:17:58 +0000283
284 hslot2 = udp_hashslot2(udptable, udp_sk(sk)->udp_portaddr_hash);
285 spin_lock(&hslot2->lock);
286 hlist_nulls_add_head_rcu(&udp_sk(sk)->udp_portaddr_node,
287 &hslot2->head);
288 hslot2->count++;
289 spin_unlock(&hslot2->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290 }
Gerrit Renker25030a72006-08-26 20:06:05 -0700291 error = 0;
Eric Dumazet645ca702008-10-29 01:41:45 -0700292fail_unlock:
293 spin_unlock_bh(&hslot->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700294fail:
Gerrit Renker25030a72006-08-26 20:06:05 -0700295 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700296}
Eric Dumazetc482c562009-07-17 00:26:32 +0000297EXPORT_SYMBOL(udp_lib_get_port);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700298
Vlad Yasevich499923c2009-04-09 17:37:33 +0000299static int ipv4_rcv_saddr_equal(const struct sock *sk1, const struct sock *sk2)
David S. Millerdb8dac22008-03-06 16:22:02 -0800300{
301 struct inet_sock *inet1 = inet_sk(sk1), *inet2 = inet_sk(sk2);
302
Eric Dumazetc482c562009-07-17 00:26:32 +0000303 return (!ipv6_only_sock(sk2) &&
Eric Dumazetc720c7e2009-10-15 06:30:45 +0000304 (!inet1->inet_rcv_saddr || !inet2->inet_rcv_saddr ||
305 inet1->inet_rcv_saddr == inet2->inet_rcv_saddr));
David S. Millerdb8dac22008-03-06 16:22:02 -0800306}
307
Eric Dumazetd4cada42009-11-08 10:17:30 +0000308static unsigned int udp4_portaddr_hash(struct net *net, __be32 saddr,
309 unsigned int port)
310{
Eric Dumazet0eae88f2010-04-20 19:06:52 -0700311 return jhash_1word((__force u32)saddr, net_hash_mix(net)) ^ port;
Eric Dumazetd4cada42009-11-08 10:17:30 +0000312}
313
Pavel Emelyanov6ba5a3c2008-03-22 16:51:21 -0700314int udp_v4_get_port(struct sock *sk, unsigned short snum)
David S. Millerdb8dac22008-03-06 16:22:02 -0800315{
Eric Dumazet30fff922009-11-09 05:26:33 +0000316 unsigned int hash2_nulladdr =
Eric Dumazet0eae88f2010-04-20 19:06:52 -0700317 udp4_portaddr_hash(sock_net(sk), htonl(INADDR_ANY), snum);
Eric Dumazet30fff922009-11-09 05:26:33 +0000318 unsigned int hash2_partial =
319 udp4_portaddr_hash(sock_net(sk), inet_sk(sk)->inet_rcv_saddr, 0);
320
Eric Dumazetd4cada42009-11-08 10:17:30 +0000321 /* precompute partial secondary hash */
Eric Dumazet30fff922009-11-09 05:26:33 +0000322 udp_sk(sk)->udp_portaddr_hash = hash2_partial;
323 return udp_lib_get_port(sk, snum, ipv4_rcv_saddr_equal, hash2_nulladdr);
David S. Millerdb8dac22008-03-06 16:22:02 -0800324}
325
Eric Dumazet645ca702008-10-29 01:41:45 -0700326static inline int compute_score(struct sock *sk, struct net *net, __be32 saddr,
327 unsigned short hnum,
328 __be16 sport, __be32 daddr, __be16 dport, int dif)
329{
330 int score = -1;
331
Eric Dumazetd4cada42009-11-08 10:17:30 +0000332 if (net_eq(sock_net(sk), net) && udp_sk(sk)->udp_port_hash == hnum &&
Eric Dumazet645ca702008-10-29 01:41:45 -0700333 !ipv6_only_sock(sk)) {
334 struct inet_sock *inet = inet_sk(sk);
335
336 score = (sk->sk_family == PF_INET ? 1 : 0);
Eric Dumazetc720c7e2009-10-15 06:30:45 +0000337 if (inet->inet_rcv_saddr) {
338 if (inet->inet_rcv_saddr != daddr)
Eric Dumazet645ca702008-10-29 01:41:45 -0700339 return -1;
340 score += 2;
341 }
Eric Dumazetc720c7e2009-10-15 06:30:45 +0000342 if (inet->inet_daddr) {
343 if (inet->inet_daddr != saddr)
Eric Dumazet645ca702008-10-29 01:41:45 -0700344 return -1;
345 score += 2;
346 }
Eric Dumazetc720c7e2009-10-15 06:30:45 +0000347 if (inet->inet_dport) {
348 if (inet->inet_dport != sport)
Eric Dumazet645ca702008-10-29 01:41:45 -0700349 return -1;
350 score += 2;
351 }
352 if (sk->sk_bound_dev_if) {
353 if (sk->sk_bound_dev_if != dif)
354 return -1;
355 score += 2;
356 }
357 }
358 return score;
359}
360
Eric Dumazet5051ebd2009-11-08 10:18:11 +0000361/*
362 * In this second variant, we check (daddr, dport) matches (inet_rcv_sadd, inet_num)
363 */
364#define SCORE2_MAX (1 + 2 + 2 + 2)
365static inline int compute_score2(struct sock *sk, struct net *net,
366 __be32 saddr, __be16 sport,
367 __be32 daddr, unsigned int hnum, int dif)
368{
369 int score = -1;
370
371 if (net_eq(sock_net(sk), net) && !ipv6_only_sock(sk)) {
372 struct inet_sock *inet = inet_sk(sk);
373
374 if (inet->inet_rcv_saddr != daddr)
375 return -1;
376 if (inet->inet_num != hnum)
377 return -1;
378
379 score = (sk->sk_family == PF_INET ? 1 : 0);
380 if (inet->inet_daddr) {
381 if (inet->inet_daddr != saddr)
382 return -1;
383 score += 2;
384 }
385 if (inet->inet_dport) {
386 if (inet->inet_dport != sport)
387 return -1;
388 score += 2;
389 }
390 if (sk->sk_bound_dev_if) {
391 if (sk->sk_bound_dev_if != dif)
392 return -1;
393 score += 2;
394 }
395 }
396 return score;
397}
398
Eric Dumazet5051ebd2009-11-08 10:18:11 +0000399
400/* called with read_rcu_lock() */
401static struct sock *udp4_lib_lookup2(struct net *net,
402 __be32 saddr, __be16 sport,
403 __be32 daddr, unsigned int hnum, int dif,
404 struct udp_hslot *hslot2, unsigned int slot2)
405{
406 struct sock *sk, *result;
407 struct hlist_nulls_node *node;
408 int score, badness;
409
410begin:
411 result = NULL;
412 badness = -1;
413 udp_portaddr_for_each_entry_rcu(sk, node, &hslot2->head) {
414 score = compute_score2(sk, net, saddr, sport,
415 daddr, hnum, dif);
416 if (score > badness) {
417 result = sk;
418 badness = score;
419 if (score == SCORE2_MAX)
420 goto exact_match;
421 }
422 }
423 /*
424 * if the nulls value we got at the end of this lookup is
425 * not the expected one, we must restart lookup.
426 * We probably met an item that was moved to another chain.
427 */
428 if (get_nulls_value(node) != slot2)
429 goto begin;
430
431 if (result) {
432exact_match:
433 if (unlikely(!atomic_inc_not_zero(&result->sk_refcnt)))
434 result = NULL;
435 else if (unlikely(compute_score2(result, net, saddr, sport,
436 daddr, hnum, dif) < badness)) {
437 sock_put(result);
438 goto begin;
439 }
440 }
441 return result;
442}
443
David S. Millerdb8dac22008-03-06 16:22:02 -0800444/* UDP is nearly always wildcards out the wazoo, it makes no sense to try
445 * harder than this. -DaveM
446 */
447static struct sock *__udp4_lib_lookup(struct net *net, __be32 saddr,
448 __be16 sport, __be32 daddr, __be16 dport,
Eric Dumazet645ca702008-10-29 01:41:45 -0700449 int dif, struct udp_table *udptable)
David S. Millerdb8dac22008-03-06 16:22:02 -0800450{
Eric Dumazet271b72c2008-10-29 02:11:14 -0700451 struct sock *sk, *result;
Eric Dumazet88ab1932008-11-16 19:39:21 -0800452 struct hlist_nulls_node *node;
David S. Millerdb8dac22008-03-06 16:22:02 -0800453 unsigned short hnum = ntohs(dport);
Eric Dumazet5051ebd2009-11-08 10:18:11 +0000454 unsigned int hash2, slot2, slot = udp_hashfn(net, hnum, udptable->mask);
455 struct udp_hslot *hslot2, *hslot = &udptable->hash[slot];
Eric Dumazet271b72c2008-10-29 02:11:14 -0700456 int score, badness;
David S. Millerdb8dac22008-03-06 16:22:02 -0800457
Eric Dumazet271b72c2008-10-29 02:11:14 -0700458 rcu_read_lock();
Eric Dumazet5051ebd2009-11-08 10:18:11 +0000459 if (hslot->count > 10) {
460 hash2 = udp4_portaddr_hash(net, daddr, hnum);
461 slot2 = hash2 & udptable->mask;
462 hslot2 = &udptable->hash2[slot2];
463 if (hslot->count < hslot2->count)
464 goto begin;
465
466 result = udp4_lib_lookup2(net, saddr, sport,
467 daddr, hnum, dif,
468 hslot2, slot2);
469 if (!result) {
Eric Dumazet0eae88f2010-04-20 19:06:52 -0700470 hash2 = udp4_portaddr_hash(net, htonl(INADDR_ANY), hnum);
Eric Dumazet5051ebd2009-11-08 10:18:11 +0000471 slot2 = hash2 & udptable->mask;
472 hslot2 = &udptable->hash2[slot2];
473 if (hslot->count < hslot2->count)
474 goto begin;
475
Jorge Boncompte [DTI2]1223c672010-04-08 04:56:48 +0000476 result = udp4_lib_lookup2(net, saddr, sport,
Eric Dumazet0eae88f2010-04-20 19:06:52 -0700477 htonl(INADDR_ANY), hnum, dif,
Eric Dumazet5051ebd2009-11-08 10:18:11 +0000478 hslot2, slot2);
479 }
480 rcu_read_unlock();
481 return result;
482 }
Eric Dumazet271b72c2008-10-29 02:11:14 -0700483begin:
484 result = NULL;
485 badness = -1;
Eric Dumazet88ab1932008-11-16 19:39:21 -0800486 sk_nulls_for_each_rcu(sk, node, &hslot->head) {
Eric Dumazet645ca702008-10-29 01:41:45 -0700487 score = compute_score(sk, net, saddr, hnum, sport,
488 daddr, dport, dif);
489 if (score > badness) {
490 result = sk;
491 badness = score;
David S. Millerdb8dac22008-03-06 16:22:02 -0800492 }
493 }
Eric Dumazet88ab1932008-11-16 19:39:21 -0800494 /*
495 * if the nulls value we got at the end of this lookup is
496 * not the expected one, we must restart lookup.
497 * We probably met an item that was moved to another chain.
498 */
Eric Dumazet5051ebd2009-11-08 10:18:11 +0000499 if (get_nulls_value(node) != slot)
Eric Dumazet88ab1932008-11-16 19:39:21 -0800500 goto begin;
501
Eric Dumazet271b72c2008-10-29 02:11:14 -0700502 if (result) {
503 if (unlikely(!atomic_inc_not_zero(&result->sk_refcnt)))
504 result = NULL;
505 else if (unlikely(compute_score(result, net, saddr, hnum, sport,
506 daddr, dport, dif) < badness)) {
507 sock_put(result);
508 goto begin;
509 }
510 }
511 rcu_read_unlock();
David S. Millerdb8dac22008-03-06 16:22:02 -0800512 return result;
513}
514
KOVACS Krisztian607c4aa2008-10-07 12:38:32 -0700515static inline struct sock *__udp4_lib_lookup_skb(struct sk_buff *skb,
516 __be16 sport, __be16 dport,
Eric Dumazet645ca702008-10-29 01:41:45 -0700517 struct udp_table *udptable)
KOVACS Krisztian607c4aa2008-10-07 12:38:32 -0700518{
KOVACS Krisztian23542612008-10-07 12:41:01 -0700519 struct sock *sk;
KOVACS Krisztian607c4aa2008-10-07 12:38:32 -0700520 const struct iphdr *iph = ip_hdr(skb);
521
KOVACS Krisztian23542612008-10-07 12:41:01 -0700522 if (unlikely(sk = skb_steal_sock(skb)))
523 return sk;
524 else
Eric Dumazetadf30902009-06-02 05:19:30 +0000525 return __udp4_lib_lookup(dev_net(skb_dst(skb)->dev), iph->saddr, sport,
KOVACS Krisztian23542612008-10-07 12:41:01 -0700526 iph->daddr, dport, inet_iif(skb),
527 udptable);
KOVACS Krisztian607c4aa2008-10-07 12:38:32 -0700528}
529
KOVACS Krisztianbcd41302008-10-01 07:48:10 -0700530struct sock *udp4_lib_lookup(struct net *net, __be32 saddr, __be16 sport,
531 __be32 daddr, __be16 dport, int dif)
532{
Eric Dumazet645ca702008-10-29 01:41:45 -0700533 return __udp4_lib_lookup(net, saddr, sport, daddr, dport, dif, &udp_table);
KOVACS Krisztianbcd41302008-10-01 07:48:10 -0700534}
535EXPORT_SYMBOL_GPL(udp4_lib_lookup);
536
Eric Dumazet920a4612008-11-01 21:22:23 -0700537static inline struct sock *udp_v4_mcast_next(struct net *net, struct sock *sk,
David S. Millerdb8dac22008-03-06 16:22:02 -0800538 __be16 loc_port, __be32 loc_addr,
539 __be16 rmt_port, __be32 rmt_addr,
540 int dif)
541{
Eric Dumazet88ab1932008-11-16 19:39:21 -0800542 struct hlist_nulls_node *node;
David S. Millerdb8dac22008-03-06 16:22:02 -0800543 struct sock *s = sk;
544 unsigned short hnum = ntohs(loc_port);
545
Eric Dumazet88ab1932008-11-16 19:39:21 -0800546 sk_nulls_for_each_from(s, node) {
David S. Millerdb8dac22008-03-06 16:22:02 -0800547 struct inet_sock *inet = inet_sk(s);
548
Joe Perches9d4fb272009-11-23 10:41:23 -0800549 if (!net_eq(sock_net(s), net) ||
550 udp_sk(s)->udp_port_hash != hnum ||
551 (inet->inet_daddr && inet->inet_daddr != rmt_addr) ||
552 (inet->inet_dport != rmt_port && inet->inet_dport) ||
553 (inet->inet_rcv_saddr &&
554 inet->inet_rcv_saddr != loc_addr) ||
555 ipv6_only_sock(s) ||
David S. Millerdb8dac22008-03-06 16:22:02 -0800556 (s->sk_bound_dev_if && s->sk_bound_dev_if != dif))
557 continue;
558 if (!ip_mc_sf_allow(s, loc_addr, rmt_addr, dif))
559 continue;
560 goto found;
561 }
562 s = NULL;
563found:
564 return s;
565}
566
567/*
568 * This routine is called by the ICMP module when it gets some
569 * sort of error condition. If err < 0 then the socket should
570 * be closed and the error returned to the user. If err > 0
571 * it's just the icmp type << 8 | icmp code.
572 * Header points to the ip header of the error packet. We move
573 * on past this. Then (as it used to claim before adjustment)
574 * header points to the first 8 bytes of the udp header. We need
575 * to find the appropriate port.
576 */
577
Eric Dumazet645ca702008-10-29 01:41:45 -0700578void __udp4_lib_err(struct sk_buff *skb, u32 info, struct udp_table *udptable)
David S. Millerdb8dac22008-03-06 16:22:02 -0800579{
580 struct inet_sock *inet;
Eric Dumazetc482c562009-07-17 00:26:32 +0000581 struct iphdr *iph = (struct iphdr *)skb->data;
582 struct udphdr *uh = (struct udphdr *)(skb->data+(iph->ihl<<2));
David S. Millerdb8dac22008-03-06 16:22:02 -0800583 const int type = icmp_hdr(skb)->type;
584 const int code = icmp_hdr(skb)->code;
585 struct sock *sk;
586 int harderr;
587 int err;
Pavel Emelyanovfd54d712008-07-14 23:01:40 -0700588 struct net *net = dev_net(skb->dev);
David S. Millerdb8dac22008-03-06 16:22:02 -0800589
Pavel Emelyanovfd54d712008-07-14 23:01:40 -0700590 sk = __udp4_lib_lookup(net, iph->daddr, uh->dest,
David S. Millerdb8dac22008-03-06 16:22:02 -0800591 iph->saddr, uh->source, skb->dev->ifindex, udptable);
592 if (sk == NULL) {
Pavel Emelyanovdcfc23c2008-07-14 23:03:00 -0700593 ICMP_INC_STATS_BH(net, ICMP_MIB_INERRORS);
David S. Millerdb8dac22008-03-06 16:22:02 -0800594 return; /* No socket for error */
595 }
596
597 err = 0;
598 harderr = 0;
599 inet = inet_sk(sk);
600
601 switch (type) {
602 default:
603 case ICMP_TIME_EXCEEDED:
604 err = EHOSTUNREACH;
605 break;
606 case ICMP_SOURCE_QUENCH:
607 goto out;
608 case ICMP_PARAMETERPROB:
609 err = EPROTO;
610 harderr = 1;
611 break;
612 case ICMP_DEST_UNREACH:
613 if (code == ICMP_FRAG_NEEDED) { /* Path MTU discovery */
614 if (inet->pmtudisc != IP_PMTUDISC_DONT) {
615 err = EMSGSIZE;
616 harderr = 1;
617 break;
618 }
619 goto out;
620 }
621 err = EHOSTUNREACH;
622 if (code <= NR_ICMP_UNREACH) {
623 harderr = icmp_err_convert[code].fatal;
624 err = icmp_err_convert[code].errno;
625 }
626 break;
627 }
628
629 /*
630 * RFC1122: OK. Passes ICMP errors back to application, as per
631 * 4.1.3.3.
632 */
633 if (!inet->recverr) {
634 if (!harderr || sk->sk_state != TCP_ESTABLISHED)
635 goto out;
636 } else {
Eric Dumazet29030372010-05-29 00:20:48 -0700637 bh_lock_sock(sk);
Eric Dumazetc482c562009-07-17 00:26:32 +0000638 ip_icmp_error(sk, skb, err, uh->dest, info, (u8 *)(uh+1));
Eric Dumazet29030372010-05-29 00:20:48 -0700639 bh_unlock_sock(sk);
David S. Millerdb8dac22008-03-06 16:22:02 -0800640 }
641 sk->sk_err = err;
642 sk->sk_error_report(sk);
643out:
644 sock_put(sk);
645}
646
647void udp_err(struct sk_buff *skb, u32 info)
648{
Eric Dumazet645ca702008-10-29 01:41:45 -0700649 __udp4_lib_err(skb, info, &udp_table);
David S. Millerdb8dac22008-03-06 16:22:02 -0800650}
651
652/*
653 * Throw away all pending data and cancel the corking. Socket is locked.
654 */
Denis V. Lunev36d926b2008-06-04 15:49:07 +0400655void udp_flush_pending_frames(struct sock *sk)
David S. Millerdb8dac22008-03-06 16:22:02 -0800656{
657 struct udp_sock *up = udp_sk(sk);
658
659 if (up->pending) {
660 up->len = 0;
661 up->pending = 0;
662 ip_flush_pending_frames(sk);
663 }
664}
Denis V. Lunev36d926b2008-06-04 15:49:07 +0400665EXPORT_SYMBOL(udp_flush_pending_frames);
David S. Millerdb8dac22008-03-06 16:22:02 -0800666
667/**
668 * udp4_hwcsum_outgoing - handle outgoing HW checksumming
669 * @sk: socket we are sending on
670 * @skb: sk_buff containing the filled-in UDP header
671 * (checksum field must be zeroed out)
672 */
673static void udp4_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb,
Eric Dumazetc482c562009-07-17 00:26:32 +0000674 __be32 src, __be32 dst, int len)
David S. Millerdb8dac22008-03-06 16:22:02 -0800675{
676 unsigned int offset;
677 struct udphdr *uh = udp_hdr(skb);
678 __wsum csum = 0;
679
680 if (skb_queue_len(&sk->sk_write_queue) == 1) {
681 /*
682 * Only one fragment on the socket.
683 */
684 skb->csum_start = skb_transport_header(skb) - skb->head;
685 skb->csum_offset = offsetof(struct udphdr, check);
686 uh->check = ~csum_tcpudp_magic(src, dst, len, IPPROTO_UDP, 0);
687 } else {
688 /*
689 * HW-checksum won't work as there are two or more
690 * fragments on the socket so that all csums of sk_buffs
691 * should be together
692 */
693 offset = skb_transport_offset(skb);
694 skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
695
696 skb->ip_summed = CHECKSUM_NONE;
697
698 skb_queue_walk(&sk->sk_write_queue, skb) {
699 csum = csum_add(csum, skb->csum);
700 }
701
702 uh->check = csum_tcpudp_magic(src, dst, len, IPPROTO_UDP, csum);
703 if (uh->check == 0)
704 uh->check = CSUM_MANGLED_0;
705 }
706}
707
708/*
709 * Push out all pending data as one UDP datagram. Socket is locked.
710 */
711static int udp_push_pending_frames(struct sock *sk)
712{
713 struct udp_sock *up = udp_sk(sk);
714 struct inet_sock *inet = inet_sk(sk);
715 struct flowi *fl = &inet->cork.fl;
716 struct sk_buff *skb;
717 struct udphdr *uh;
718 int err = 0;
719 int is_udplite = IS_UDPLITE(sk);
720 __wsum csum = 0;
721
722 /* Grab the skbuff where UDP header space exists. */
723 if ((skb = skb_peek(&sk->sk_write_queue)) == NULL)
724 goto out;
725
726 /*
727 * Create a UDP header
728 */
729 uh = udp_hdr(skb);
730 uh->source = fl->fl_ip_sport;
731 uh->dest = fl->fl_ip_dport;
732 uh->len = htons(up->len);
733 uh->check = 0;
734
735 if (is_udplite) /* UDP-Lite */
736 csum = udplite_csum_outgoing(sk, skb);
737
738 else if (sk->sk_no_check == UDP_CSUM_NOXMIT) { /* UDP csum disabled */
739
740 skb->ip_summed = CHECKSUM_NONE;
741 goto send;
742
743 } else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */
744
Eric Dumazetc482c562009-07-17 00:26:32 +0000745 udp4_hwcsum_outgoing(sk, skb, fl->fl4_src, fl->fl4_dst, up->len);
David S. Millerdb8dac22008-03-06 16:22:02 -0800746 goto send;
747
748 } else /* `normal' UDP */
749 csum = udp_csum_outgoing(sk, skb);
750
751 /* add protocol-dependent pseudo-header */
752 uh->check = csum_tcpudp_magic(fl->fl4_src, fl->fl4_dst, up->len,
Eric Dumazetc482c562009-07-17 00:26:32 +0000753 sk->sk_protocol, csum);
David S. Millerdb8dac22008-03-06 16:22:02 -0800754 if (uh->check == 0)
755 uh->check = CSUM_MANGLED_0;
756
757send:
758 err = ip_push_pending_frames(sk);
Eric Dumazet6ce9e7b2009-09-02 18:05:33 -0700759 if (err) {
760 if (err == -ENOBUFS && !inet->recverr) {
761 UDP_INC_STATS_USER(sock_net(sk),
762 UDP_MIB_SNDBUFERRORS, is_udplite);
763 err = 0;
764 }
765 } else
766 UDP_INC_STATS_USER(sock_net(sk),
767 UDP_MIB_OUTDATAGRAMS, is_udplite);
David S. Millerdb8dac22008-03-06 16:22:02 -0800768out:
769 up->len = 0;
770 up->pending = 0;
David S. Millerdb8dac22008-03-06 16:22:02 -0800771 return err;
772}
773
774int udp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
775 size_t len)
776{
777 struct inet_sock *inet = inet_sk(sk);
778 struct udp_sock *up = udp_sk(sk);
779 int ulen = len;
780 struct ipcm_cookie ipc;
781 struct rtable *rt = NULL;
782 int free = 0;
783 int connected = 0;
784 __be32 daddr, faddr, saddr;
785 __be16 dport;
786 u8 tos;
787 int err, is_udplite = IS_UDPLITE(sk);
788 int corkreq = up->corkflag || msg->msg_flags&MSG_MORE;
789 int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
790
791 if (len > 0xFFFF)
792 return -EMSGSIZE;
793
794 /*
795 * Check the flags.
796 */
797
Eric Dumazetc482c562009-07-17 00:26:32 +0000798 if (msg->msg_flags & MSG_OOB) /* Mirror BSD error message compatibility */
David S. Millerdb8dac22008-03-06 16:22:02 -0800799 return -EOPNOTSUPP;
800
801 ipc.opt = NULL;
Patrick Ohly51f31ca2009-02-12 05:03:39 +0000802 ipc.shtx.flags = 0;
David S. Millerdb8dac22008-03-06 16:22:02 -0800803
804 if (up->pending) {
805 /*
806 * There are pending frames.
807 * The socket lock must be held while it's corked.
808 */
809 lock_sock(sk);
810 if (likely(up->pending)) {
811 if (unlikely(up->pending != AF_INET)) {
812 release_sock(sk);
813 return -EINVAL;
814 }
815 goto do_append_data;
816 }
817 release_sock(sk);
818 }
819 ulen += sizeof(struct udphdr);
820
821 /*
822 * Get and verify the address.
823 */
824 if (msg->msg_name) {
Eric Dumazetc482c562009-07-17 00:26:32 +0000825 struct sockaddr_in * usin = (struct sockaddr_in *)msg->msg_name;
David S. Millerdb8dac22008-03-06 16:22:02 -0800826 if (msg->msg_namelen < sizeof(*usin))
827 return -EINVAL;
828 if (usin->sin_family != AF_INET) {
829 if (usin->sin_family != AF_UNSPEC)
830 return -EAFNOSUPPORT;
831 }
832
833 daddr = usin->sin_addr.s_addr;
834 dport = usin->sin_port;
835 if (dport == 0)
836 return -EINVAL;
837 } else {
838 if (sk->sk_state != TCP_ESTABLISHED)
839 return -EDESTADDRREQ;
Eric Dumazetc720c7e2009-10-15 06:30:45 +0000840 daddr = inet->inet_daddr;
841 dport = inet->inet_dport;
David S. Millerdb8dac22008-03-06 16:22:02 -0800842 /* Open fast path for connected socket.
843 Route will not be used, if at least one option is set.
844 */
845 connected = 1;
846 }
Eric Dumazetc720c7e2009-10-15 06:30:45 +0000847 ipc.addr = inet->inet_saddr;
David S. Millerdb8dac22008-03-06 16:22:02 -0800848
849 ipc.oif = sk->sk_bound_dev_if;
Patrick Ohly51f31ca2009-02-12 05:03:39 +0000850 err = sock_tx_timestamp(msg, sk, &ipc.shtx);
851 if (err)
852 return err;
David S. Millerdb8dac22008-03-06 16:22:02 -0800853 if (msg->msg_controllen) {
YOSHIFUJI Hideaki3b1e0a62008-03-26 02:26:21 +0900854 err = ip_cmsg_send(sock_net(sk), msg, &ipc);
David S. Millerdb8dac22008-03-06 16:22:02 -0800855 if (err)
856 return err;
857 if (ipc.opt)
858 free = 1;
859 connected = 0;
860 }
861 if (!ipc.opt)
862 ipc.opt = inet->opt;
863
864 saddr = ipc.addr;
865 ipc.addr = faddr = daddr;
866
867 if (ipc.opt && ipc.opt->srr) {
868 if (!daddr)
869 return -EINVAL;
870 faddr = ipc.opt->faddr;
871 connected = 0;
872 }
873 tos = RT_TOS(inet->tos);
874 if (sock_flag(sk, SOCK_LOCALROUTE) ||
875 (msg->msg_flags & MSG_DONTROUTE) ||
876 (ipc.opt && ipc.opt->is_strictroute)) {
877 tos |= RTO_ONLINK;
878 connected = 0;
879 }
880
881 if (ipv4_is_multicast(daddr)) {
882 if (!ipc.oif)
883 ipc.oif = inet->mc_index;
884 if (!saddr)
885 saddr = inet->mc_addr;
886 connected = 0;
887 }
888
889 if (connected)
Eric Dumazetc482c562009-07-17 00:26:32 +0000890 rt = (struct rtable *)sk_dst_check(sk, 0);
David S. Millerdb8dac22008-03-06 16:22:02 -0800891
892 if (rt == NULL) {
893 struct flowi fl = { .oif = ipc.oif,
Atis Elsts914a9ab2009-10-01 15:16:49 -0700894 .mark = sk->sk_mark,
David S. Millerdb8dac22008-03-06 16:22:02 -0800895 .nl_u = { .ip4_u =
896 { .daddr = faddr,
897 .saddr = saddr,
898 .tos = tos } },
899 .proto = sk->sk_protocol,
Balazs Scheidlera134f852008-11-20 01:07:24 -0800900 .flags = inet_sk_flowi_flags(sk),
David S. Millerdb8dac22008-03-06 16:22:02 -0800901 .uli_u = { .ports =
Eric Dumazetc720c7e2009-10-15 06:30:45 +0000902 { .sport = inet->inet_sport,
David S. Millerdb8dac22008-03-06 16:22:02 -0800903 .dport = dport } } };
Pavel Emelyanov84a3aa02008-07-16 20:19:08 -0700904 struct net *net = sock_net(sk);
905
David S. Millerdb8dac22008-03-06 16:22:02 -0800906 security_sk_classify_flow(sk, &fl);
Pavel Emelyanov84a3aa02008-07-16 20:19:08 -0700907 err = ip_route_output_flow(net, &rt, &fl, sk, 1);
David S. Millerdb8dac22008-03-06 16:22:02 -0800908 if (err) {
909 if (err == -ENETUNREACH)
Pavel Emelyanov7c73a6f2008-07-16 20:20:11 -0700910 IP_INC_STATS_BH(net, IPSTATS_MIB_OUTNOROUTES);
David S. Millerdb8dac22008-03-06 16:22:02 -0800911 goto out;
912 }
913
914 err = -EACCES;
915 if ((rt->rt_flags & RTCF_BROADCAST) &&
916 !sock_flag(sk, SOCK_BROADCAST))
917 goto out;
918 if (connected)
919 sk_dst_set(sk, dst_clone(&rt->u.dst));
920 }
921
922 if (msg->msg_flags&MSG_CONFIRM)
923 goto do_confirm;
924back_from_confirm:
925
926 saddr = rt->rt_src;
927 if (!ipc.addr)
928 daddr = ipc.addr = rt->rt_dst;
929
930 lock_sock(sk);
931 if (unlikely(up->pending)) {
932 /* The socket is already corked while preparing it. */
933 /* ... which is an evident application bug. --ANK */
934 release_sock(sk);
935
936 LIMIT_NETDEBUG(KERN_DEBUG "udp cork app bug 2\n");
937 err = -EINVAL;
938 goto out;
939 }
940 /*
941 * Now cork the socket to pend data.
942 */
943 inet->cork.fl.fl4_dst = daddr;
944 inet->cork.fl.fl_ip_dport = dport;
945 inet->cork.fl.fl4_src = saddr;
Eric Dumazetc720c7e2009-10-15 06:30:45 +0000946 inet->cork.fl.fl_ip_sport = inet->inet_sport;
David S. Millerdb8dac22008-03-06 16:22:02 -0800947 up->pending = AF_INET;
948
949do_append_data:
950 up->len += ulen;
951 getfrag = is_udplite ? udplite_getfrag : ip_generic_getfrag;
952 err = ip_append_data(sk, getfrag, msg->msg_iov, ulen,
Eric Dumazet2e77d892008-11-24 15:52:46 -0800953 sizeof(struct udphdr), &ipc, &rt,
David S. Millerdb8dac22008-03-06 16:22:02 -0800954 corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags);
955 if (err)
956 udp_flush_pending_frames(sk);
957 else if (!corkreq)
958 err = udp_push_pending_frames(sk);
959 else if (unlikely(skb_queue_empty(&sk->sk_write_queue)))
960 up->pending = 0;
961 release_sock(sk);
962
963out:
964 ip_rt_put(rt);
965 if (free)
966 kfree(ipc.opt);
967 if (!err)
968 return len;
969 /*
970 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space. Reporting
971 * ENOBUFS might not be good (it's not tunable per se), but otherwise
972 * we don't have a good statistic (IpOutDiscards but it can be too many
973 * things). We could add another new stat but at least for now that
974 * seems like overkill.
975 */
976 if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
Pavel Emelyanov629ca232008-07-05 21:18:07 -0700977 UDP_INC_STATS_USER(sock_net(sk),
978 UDP_MIB_SNDBUFERRORS, is_udplite);
David S. Millerdb8dac22008-03-06 16:22:02 -0800979 }
980 return err;
981
982do_confirm:
983 dst_confirm(&rt->u.dst);
984 if (!(msg->msg_flags&MSG_PROBE) || len)
985 goto back_from_confirm;
986 err = 0;
987 goto out;
988}
Eric Dumazetc482c562009-07-17 00:26:32 +0000989EXPORT_SYMBOL(udp_sendmsg);
David S. Millerdb8dac22008-03-06 16:22:02 -0800990
991int udp_sendpage(struct sock *sk, struct page *page, int offset,
992 size_t size, int flags)
993{
994 struct udp_sock *up = udp_sk(sk);
995 int ret;
996
997 if (!up->pending) {
998 struct msghdr msg = { .msg_flags = flags|MSG_MORE };
999
1000 /* Call udp_sendmsg to specify destination address which
1001 * sendpage interface can't pass.
1002 * This will succeed only when the socket is connected.
1003 */
1004 ret = udp_sendmsg(NULL, sk, &msg, 0);
1005 if (ret < 0)
1006 return ret;
1007 }
1008
1009 lock_sock(sk);
1010
1011 if (unlikely(!up->pending)) {
1012 release_sock(sk);
1013
1014 LIMIT_NETDEBUG(KERN_DEBUG "udp cork app bug 3\n");
1015 return -EINVAL;
1016 }
1017
1018 ret = ip_append_page(sk, page, offset, size, flags);
1019 if (ret == -EOPNOTSUPP) {
1020 release_sock(sk);
1021 return sock_no_sendpage(sk->sk_socket, page, offset,
1022 size, flags);
1023 }
1024 if (ret < 0) {
1025 udp_flush_pending_frames(sk);
1026 goto out;
1027 }
1028
1029 up->len += size;
1030 if (!(up->corkflag || (flags&MSG_MORE)))
1031 ret = udp_push_pending_frames(sk);
1032 if (!ret)
1033 ret = size;
1034out:
1035 release_sock(sk);
1036 return ret;
1037}
1038
Eric Dumazet85584672009-10-09 04:43:40 +00001039
1040/**
1041 * first_packet_length - return length of first packet in receive queue
1042 * @sk: socket
1043 *
1044 * Drops all bad checksum frames, until a valid one is found.
1045 * Returns the length of found skb, or 0 if none is found.
1046 */
1047static unsigned int first_packet_length(struct sock *sk)
1048{
1049 struct sk_buff_head list_kill, *rcvq = &sk->sk_receive_queue;
1050 struct sk_buff *skb;
1051 unsigned int res;
1052
1053 __skb_queue_head_init(&list_kill);
1054
1055 spin_lock_bh(&rcvq->lock);
1056 while ((skb = skb_peek(rcvq)) != NULL &&
1057 udp_lib_checksum_complete(skb)) {
1058 UDP_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS,
1059 IS_UDPLITE(sk));
Eric Dumazet8edf19c2009-10-15 00:12:40 +00001060 atomic_inc(&sk->sk_drops);
Eric Dumazet85584672009-10-09 04:43:40 +00001061 __skb_unlink(skb, rcvq);
1062 __skb_queue_tail(&list_kill, skb);
1063 }
1064 res = skb ? skb->len : 0;
1065 spin_unlock_bh(&rcvq->lock);
1066
1067 if (!skb_queue_empty(&list_kill)) {
Eric Dumazet8a74ad62010-05-26 19:20:18 +00001068 bool slow = lock_sock_fast(sk);
1069
Eric Dumazet85584672009-10-09 04:43:40 +00001070 __skb_queue_purge(&list_kill);
1071 sk_mem_reclaim_partial(sk);
Eric Dumazet8a74ad62010-05-26 19:20:18 +00001072 unlock_sock_fast(sk, slow);
Eric Dumazet85584672009-10-09 04:43:40 +00001073 }
1074 return res;
1075}
1076
Linus Torvalds1da177e2005-04-16 15:20:36 -07001077/*
1078 * IOCTL requests applicable to the UDP protocol
1079 */
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +09001080
Linus Torvalds1da177e2005-04-16 15:20:36 -07001081int udp_ioctl(struct sock *sk, int cmd, unsigned long arg)
1082{
Stephen Hemminger6516c652007-03-08 20:41:55 -08001083 switch (cmd) {
1084 case SIOCOUTQ:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001085 {
Eric Dumazet31e6d362009-06-17 19:05:41 -07001086 int amount = sk_wmem_alloc_get(sk);
1087
Stephen Hemminger6516c652007-03-08 20:41:55 -08001088 return put_user(amount, (int __user *)arg);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001089 }
Stephen Hemminger6516c652007-03-08 20:41:55 -08001090
1091 case SIOCINQ:
1092 {
Eric Dumazet85584672009-10-09 04:43:40 +00001093 unsigned int amount = first_packet_length(sk);
Stephen Hemminger6516c652007-03-08 20:41:55 -08001094
Eric Dumazet85584672009-10-09 04:43:40 +00001095 if (amount)
Stephen Hemminger6516c652007-03-08 20:41:55 -08001096 /*
1097 * We will only return the amount
1098 * of this packet since that is all
1099 * that will be read.
1100 */
Eric Dumazet85584672009-10-09 04:43:40 +00001101 amount -= sizeof(struct udphdr);
1102
Stephen Hemminger6516c652007-03-08 20:41:55 -08001103 return put_user(amount, (int __user *)arg);
1104 }
1105
1106 default:
1107 return -ENOIOCTLCMD;
1108 }
1109
1110 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001111}
Eric Dumazetc482c562009-07-17 00:26:32 +00001112EXPORT_SYMBOL(udp_ioctl);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001113
David S. Millerdb8dac22008-03-06 16:22:02 -08001114/*
1115 * This should be easy, if there is something there we
1116 * return it, otherwise we block.
1117 */
1118
1119int udp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
1120 size_t len, int noblock, int flags, int *addr_len)
1121{
1122 struct inet_sock *inet = inet_sk(sk);
1123 struct sockaddr_in *sin = (struct sockaddr_in *)msg->msg_name;
1124 struct sk_buff *skb;
Gerrit Renker81d54ec2010-02-10 20:26:19 +00001125 unsigned int ulen;
David S. Millerdb8dac22008-03-06 16:22:02 -08001126 int peeked;
1127 int err;
1128 int is_udplite = IS_UDPLITE(sk);
Eric Dumazet8a74ad62010-05-26 19:20:18 +00001129 bool slow;
David S. Millerdb8dac22008-03-06 16:22:02 -08001130
1131 /*
1132 * Check any passed addresses
1133 */
1134 if (addr_len)
Eric Dumazetc482c562009-07-17 00:26:32 +00001135 *addr_len = sizeof(*sin);
David S. Millerdb8dac22008-03-06 16:22:02 -08001136
1137 if (flags & MSG_ERRQUEUE)
1138 return ip_recv_error(sk, msg, len);
1139
1140try_again:
1141 skb = __skb_recv_datagram(sk, flags | (noblock ? MSG_DONTWAIT : 0),
1142 &peeked, &err);
1143 if (!skb)
1144 goto out;
1145
1146 ulen = skb->len - sizeof(struct udphdr);
Gerrit Renker81d54ec2010-02-10 20:26:19 +00001147 if (len > ulen)
1148 len = ulen;
1149 else if (len < ulen)
David S. Millerdb8dac22008-03-06 16:22:02 -08001150 msg->msg_flags |= MSG_TRUNC;
1151
1152 /*
1153 * If checksum is needed at all, try to do it while copying the
1154 * data. If the data is truncated, or if we only want a partial
1155 * coverage checksum (UDP-Lite), do it before the copy.
1156 */
1157
Gerrit Renker81d54ec2010-02-10 20:26:19 +00001158 if (len < ulen || UDP_SKB_CB(skb)->partial_cov) {
David S. Millerdb8dac22008-03-06 16:22:02 -08001159 if (udp_lib_checksum_complete(skb))
1160 goto csum_copy_err;
1161 }
1162
1163 if (skb_csum_unnecessary(skb))
1164 err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr),
Gerrit Renker81d54ec2010-02-10 20:26:19 +00001165 msg->msg_iov, len);
David S. Millerdb8dac22008-03-06 16:22:02 -08001166 else {
Eric Dumazetc482c562009-07-17 00:26:32 +00001167 err = skb_copy_and_csum_datagram_iovec(skb,
1168 sizeof(struct udphdr),
1169 msg->msg_iov);
David S. Millerdb8dac22008-03-06 16:22:02 -08001170
1171 if (err == -EINVAL)
1172 goto csum_copy_err;
1173 }
1174
1175 if (err)
1176 goto out_free;
1177
1178 if (!peeked)
Pavel Emelyanov629ca232008-07-05 21:18:07 -07001179 UDP_INC_STATS_USER(sock_net(sk),
1180 UDP_MIB_INDATAGRAMS, is_udplite);
David S. Millerdb8dac22008-03-06 16:22:02 -08001181
Neil Horman3b885782009-10-12 13:26:31 -07001182 sock_recv_ts_and_drops(msg, sk, skb);
David S. Millerdb8dac22008-03-06 16:22:02 -08001183
1184 /* Copy the address. */
Eric Dumazetc482c562009-07-17 00:26:32 +00001185 if (sin) {
David S. Millerdb8dac22008-03-06 16:22:02 -08001186 sin->sin_family = AF_INET;
1187 sin->sin_port = udp_hdr(skb)->source;
1188 sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
1189 memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
1190 }
1191 if (inet->cmsg_flags)
1192 ip_cmsg_recv(msg, skb);
1193
Gerrit Renker81d54ec2010-02-10 20:26:19 +00001194 err = len;
David S. Millerdb8dac22008-03-06 16:22:02 -08001195 if (flags & MSG_TRUNC)
1196 err = ulen;
1197
1198out_free:
Eric Dumazet9d410c72009-10-30 05:03:53 +00001199 skb_free_datagram_locked(sk, skb);
David S. Millerdb8dac22008-03-06 16:22:02 -08001200out:
1201 return err;
1202
1203csum_copy_err:
Eric Dumazet8a74ad62010-05-26 19:20:18 +00001204 slow = lock_sock_fast(sk);
David S. Millerdb8dac22008-03-06 16:22:02 -08001205 if (!skb_kill_datagram(sk, skb, flags))
Pavel Emelyanov629ca232008-07-05 21:18:07 -07001206 UDP_INC_STATS_USER(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
Eric Dumazet8a74ad62010-05-26 19:20:18 +00001207 unlock_sock_fast(sk, slow);
David S. Millerdb8dac22008-03-06 16:22:02 -08001208
1209 if (noblock)
1210 return -EAGAIN;
1211 goto try_again;
1212}
1213
1214
Linus Torvalds1da177e2005-04-16 15:20:36 -07001215int udp_disconnect(struct sock *sk, int flags)
1216{
1217 struct inet_sock *inet = inet_sk(sk);
1218 /*
1219 * 1003.1g - break association.
1220 */
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +09001221
Linus Torvalds1da177e2005-04-16 15:20:36 -07001222 sk->sk_state = TCP_CLOSE;
Eric Dumazetc720c7e2009-10-15 06:30:45 +00001223 inet->inet_daddr = 0;
1224 inet->inet_dport = 0;
David S. Millerc58dc012010-04-27 15:05:31 -07001225 sock_rps_save_rxhash(sk, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001226 sk->sk_bound_dev_if = 0;
1227 if (!(sk->sk_userlocks & SOCK_BINDADDR_LOCK))
1228 inet_reset_saddr(sk);
1229
1230 if (!(sk->sk_userlocks & SOCK_BINDPORT_LOCK)) {
1231 sk->sk_prot->unhash(sk);
Eric Dumazetc720c7e2009-10-15 06:30:45 +00001232 inet->inet_sport = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001233 }
1234 sk_dst_reset(sk);
1235 return 0;
1236}
Eric Dumazetc482c562009-07-17 00:26:32 +00001237EXPORT_SYMBOL(udp_disconnect);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001238
Eric Dumazet645ca702008-10-29 01:41:45 -07001239void udp_lib_unhash(struct sock *sk)
1240{
Eric Dumazet723b4612008-11-25 13:55:15 -08001241 if (sk_hashed(sk)) {
1242 struct udp_table *udptable = sk->sk_prot->h.udp_table;
Eric Dumazet512615b2009-11-08 10:17:58 +00001243 struct udp_hslot *hslot, *hslot2;
1244
1245 hslot = udp_hashslot(udptable, sock_net(sk),
1246 udp_sk(sk)->udp_port_hash);
1247 hslot2 = udp_hashslot2(udptable, udp_sk(sk)->udp_portaddr_hash);
Eric Dumazet645ca702008-10-29 01:41:45 -07001248
Eric Dumazet723b4612008-11-25 13:55:15 -08001249 spin_lock_bh(&hslot->lock);
1250 if (sk_nulls_del_node_init_rcu(sk)) {
Eric Dumazetfdcc8aa92009-11-08 10:17:05 +00001251 hslot->count--;
Eric Dumazetc720c7e2009-10-15 06:30:45 +00001252 inet_sk(sk)->inet_num = 0;
Eric Dumazet723b4612008-11-25 13:55:15 -08001253 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
Eric Dumazet512615b2009-11-08 10:17:58 +00001254
1255 spin_lock(&hslot2->lock);
1256 hlist_nulls_del_init_rcu(&udp_sk(sk)->udp_portaddr_node);
1257 hslot2->count--;
1258 spin_unlock(&hslot2->lock);
Eric Dumazet723b4612008-11-25 13:55:15 -08001259 }
1260 spin_unlock_bh(&hslot->lock);
Eric Dumazet645ca702008-10-29 01:41:45 -07001261 }
Eric Dumazet645ca702008-10-29 01:41:45 -07001262}
1263EXPORT_SYMBOL(udp_lib_unhash);
1264
Herbert Xu93821772008-09-15 11:48:46 -07001265static int __udp_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
1266{
Tom Herbertfec5e652010-04-16 16:01:27 -07001267 int rc;
Herbert Xu93821772008-09-15 11:48:46 -07001268
Tom Herbertfec5e652010-04-16 16:01:27 -07001269 if (inet_sk(sk)->inet_daddr)
David S. Millerc58dc012010-04-27 15:05:31 -07001270 sock_rps_save_rxhash(sk, skb->rxhash);
Tom Herbertfec5e652010-04-16 16:01:27 -07001271
Eric Dumazetf84af322010-04-28 15:31:51 -07001272 rc = ip_queue_rcv_skb(sk, skb);
Eric Dumazet766e90372009-10-14 20:40:11 -07001273 if (rc < 0) {
1274 int is_udplite = IS_UDPLITE(sk);
1275
Herbert Xu93821772008-09-15 11:48:46 -07001276 /* Note that an ENOMEM error is charged twice */
Eric Dumazet766e90372009-10-14 20:40:11 -07001277 if (rc == -ENOMEM)
Herbert Xu93821772008-09-15 11:48:46 -07001278 UDP_INC_STATS_BH(sock_net(sk), UDP_MIB_RCVBUFERRORS,
1279 is_udplite);
Eric Dumazet766e90372009-10-14 20:40:11 -07001280 UDP_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
1281 kfree_skb(skb);
1282 return -1;
Herbert Xu93821772008-09-15 11:48:46 -07001283 }
1284
1285 return 0;
1286
Herbert Xu93821772008-09-15 11:48:46 -07001287}
1288
David S. Millerdb8dac22008-03-06 16:22:02 -08001289/* returns:
1290 * -1: error
1291 * 0: success
1292 * >0: "udp encap" protocol resubmission
1293 *
1294 * Note that in the success and error cases, the skb is assumed to
1295 * have either been requeued or freed.
1296 */
Eric Dumazetc482c562009-07-17 00:26:32 +00001297int udp_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
David S. Millerdb8dac22008-03-06 16:22:02 -08001298{
1299 struct udp_sock *up = udp_sk(sk);
1300 int rc;
1301 int is_udplite = IS_UDPLITE(sk);
1302
1303 /*
1304 * Charge it to the socket, dropping if the queue is full.
1305 */
1306 if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb))
1307 goto drop;
1308 nf_reset(skb);
1309
1310 if (up->encap_type) {
1311 /*
1312 * This is an encapsulation socket so pass the skb to
1313 * the socket's udp_encap_rcv() hook. Otherwise, just
1314 * fall through and pass this up the UDP socket.
1315 * up->encap_rcv() returns the following value:
1316 * =0 if skb was successfully passed to the encap
1317 * handler or was discarded by it.
1318 * >0 if skb should be passed on to UDP.
1319 * <0 if skb should be resubmitted as proto -N
1320 */
1321
1322 /* if we're overly short, let UDP handle it */
1323 if (skb->len > sizeof(struct udphdr) &&
1324 up->encap_rcv != NULL) {
1325 int ret;
1326
1327 ret = (*up->encap_rcv)(sk, skb);
1328 if (ret <= 0) {
Pavel Emelyanov02833282008-07-05 21:18:48 -07001329 UDP_INC_STATS_BH(sock_net(sk),
1330 UDP_MIB_INDATAGRAMS,
David S. Millerdb8dac22008-03-06 16:22:02 -08001331 is_udplite);
1332 return -ret;
1333 }
1334 }
1335
1336 /* FALLTHROUGH -- it's a UDP Packet */
1337 }
1338
1339 /*
1340 * UDP-Lite specific tests, ignored on UDP sockets
1341 */
1342 if ((is_udplite & UDPLITE_RECV_CC) && UDP_SKB_CB(skb)->partial_cov) {
1343
1344 /*
1345 * MIB statistics other than incrementing the error count are
1346 * disabled for the following two types of errors: these depend
1347 * on the application settings, not on the functioning of the
1348 * protocol stack as such.
1349 *
1350 * RFC 3828 here recommends (sec 3.3): "There should also be a
1351 * way ... to ... at least let the receiving application block
1352 * delivery of packets with coverage values less than a value
1353 * provided by the application."
1354 */
1355 if (up->pcrlen == 0) { /* full coverage was set */
1356 LIMIT_NETDEBUG(KERN_WARNING "UDPLITE: partial coverage "
1357 "%d while full coverage %d requested\n",
1358 UDP_SKB_CB(skb)->cscov, skb->len);
1359 goto drop;
1360 }
1361 /* The next case involves violating the min. coverage requested
1362 * by the receiver. This is subtle: if receiver wants x and x is
1363 * greater than the buffersize/MTU then receiver will complain
1364 * that it wants x while sender emits packets of smaller size y.
1365 * Therefore the above ...()->partial_cov statement is essential.
1366 */
1367 if (UDP_SKB_CB(skb)->cscov < up->pcrlen) {
1368 LIMIT_NETDEBUG(KERN_WARNING
1369 "UDPLITE: coverage %d too small, need min %d\n",
1370 UDP_SKB_CB(skb)->cscov, up->pcrlen);
1371 goto drop;
1372 }
1373 }
1374
1375 if (sk->sk_filter) {
1376 if (udp_lib_checksum_complete(skb))
1377 goto drop;
1378 }
1379
Eric Dumazetc3774112010-04-27 15:13:20 -07001380
1381 if (sk_rcvqueues_full(sk, skb))
1382 goto drop;
1383
Herbert Xu93821772008-09-15 11:48:46 -07001384 rc = 0;
David S. Millerdb8dac22008-03-06 16:22:02 -08001385
Herbert Xu93821772008-09-15 11:48:46 -07001386 bh_lock_sock(sk);
1387 if (!sock_owned_by_user(sk))
1388 rc = __udp_queue_rcv_skb(sk, skb);
Zhu Yia3a858f2010-03-04 18:01:47 +00001389 else if (sk_add_backlog(sk, skb)) {
Zhu Yi55349792010-03-04 18:01:42 +00001390 bh_unlock_sock(sk);
1391 goto drop;
1392 }
Herbert Xu93821772008-09-15 11:48:46 -07001393 bh_unlock_sock(sk);
1394
1395 return rc;
David S. Millerdb8dac22008-03-06 16:22:02 -08001396
1397drop:
Pavel Emelyanov02833282008-07-05 21:18:48 -07001398 UDP_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
Eric Dumazet8edf19c2009-10-15 00:12:40 +00001399 atomic_inc(&sk->sk_drops);
David S. Millerdb8dac22008-03-06 16:22:02 -08001400 kfree_skb(skb);
1401 return -1;
1402}
1403
Eric Dumazet1240d132009-11-08 10:18:44 +00001404
1405static void flush_stack(struct sock **stack, unsigned int count,
1406 struct sk_buff *skb, unsigned int final)
1407{
1408 unsigned int i;
1409 struct sk_buff *skb1 = NULL;
Eric Dumazetf6b8f322009-11-08 10:20:19 +00001410 struct sock *sk;
Eric Dumazet1240d132009-11-08 10:18:44 +00001411
1412 for (i = 0; i < count; i++) {
Eric Dumazetf6b8f322009-11-08 10:20:19 +00001413 sk = stack[i];
Eric Dumazet1240d132009-11-08 10:18:44 +00001414 if (likely(skb1 == NULL))
1415 skb1 = (i == final) ? skb : skb_clone(skb, GFP_ATOMIC);
1416
Eric Dumazetf6b8f322009-11-08 10:20:19 +00001417 if (!skb1) {
1418 atomic_inc(&sk->sk_drops);
1419 UDP_INC_STATS_BH(sock_net(sk), UDP_MIB_RCVBUFERRORS,
1420 IS_UDPLITE(sk));
1421 UDP_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS,
1422 IS_UDPLITE(sk));
1423 }
1424
1425 if (skb1 && udp_queue_rcv_skb(sk, skb1) <= 0)
Eric Dumazet1240d132009-11-08 10:18:44 +00001426 skb1 = NULL;
1427 }
1428 if (unlikely(skb1))
1429 kfree_skb(skb1);
1430}
1431
David S. Millerdb8dac22008-03-06 16:22:02 -08001432/*
1433 * Multicasts and broadcasts go to each listener.
1434 *
Eric Dumazet1240d132009-11-08 10:18:44 +00001435 * Note: called only from the BH handler context.
David S. Millerdb8dac22008-03-06 16:22:02 -08001436 */
Pavel Emelyanove3163492008-06-16 17:12:11 -07001437static int __udp4_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
David S. Millerdb8dac22008-03-06 16:22:02 -08001438 struct udphdr *uh,
1439 __be32 saddr, __be32 daddr,
Eric Dumazet645ca702008-10-29 01:41:45 -07001440 struct udp_table *udptable)
David S. Millerdb8dac22008-03-06 16:22:02 -08001441{
Eric Dumazet1240d132009-11-08 10:18:44 +00001442 struct sock *sk, *stack[256 / sizeof(struct sock *)];
Eric Dumazetf86dcc52009-10-07 00:37:59 +00001443 struct udp_hslot *hslot = udp_hashslot(udptable, net, ntohs(uh->dest));
David S. Millerdb8dac22008-03-06 16:22:02 -08001444 int dif;
Eric Dumazet1240d132009-11-08 10:18:44 +00001445 unsigned int i, count = 0;
David S. Millerdb8dac22008-03-06 16:22:02 -08001446
Eric Dumazet645ca702008-10-29 01:41:45 -07001447 spin_lock(&hslot->lock);
Eric Dumazet88ab1932008-11-16 19:39:21 -08001448 sk = sk_nulls_head(&hslot->head);
David S. Millerdb8dac22008-03-06 16:22:02 -08001449 dif = skb->dev->ifindex;
Eric Dumazet920a4612008-11-01 21:22:23 -07001450 sk = udp_v4_mcast_next(net, sk, uh->dest, daddr, uh->source, saddr, dif);
Eric Dumazet1240d132009-11-08 10:18:44 +00001451 while (sk) {
1452 stack[count++] = sk;
1453 sk = udp_v4_mcast_next(net, sk_nulls_next(sk), uh->dest,
1454 daddr, uh->source, saddr, dif);
1455 if (unlikely(count == ARRAY_SIZE(stack))) {
1456 if (!sk)
1457 break;
1458 flush_stack(stack, count, skb, ~0);
1459 count = 0;
1460 }
1461 }
1462 /*
1463 * before releasing chain lock, we must take a reference on sockets
1464 */
1465 for (i = 0; i < count; i++)
1466 sock_hold(stack[i]);
David S. Millerdb8dac22008-03-06 16:22:02 -08001467
Eric Dumazet645ca702008-10-29 01:41:45 -07001468 spin_unlock(&hslot->lock);
Eric Dumazet1240d132009-11-08 10:18:44 +00001469
1470 /*
1471 * do the slow work with no lock held
1472 */
1473 if (count) {
1474 flush_stack(stack, count, skb, count - 1);
1475
1476 for (i = 0; i < count; i++)
1477 sock_put(stack[i]);
1478 } else {
1479 kfree_skb(skb);
1480 }
David S. Millerdb8dac22008-03-06 16:22:02 -08001481 return 0;
1482}
1483
1484/* Initialize UDP checksum. If exited with zero value (success),
1485 * CHECKSUM_UNNECESSARY means, that no more checks are required.
1486 * Otherwise, csum completion requires chacksumming packet body,
1487 * including udp header and folding it to skb->csum.
1488 */
1489static inline int udp4_csum_init(struct sk_buff *skb, struct udphdr *uh,
1490 int proto)
1491{
1492 const struct iphdr *iph;
1493 int err;
1494
1495 UDP_SKB_CB(skb)->partial_cov = 0;
1496 UDP_SKB_CB(skb)->cscov = skb->len;
1497
1498 if (proto == IPPROTO_UDPLITE) {
1499 err = udplite_checksum_init(skb, uh);
1500 if (err)
1501 return err;
1502 }
1503
1504 iph = ip_hdr(skb);
1505 if (uh->check == 0) {
1506 skb->ip_summed = CHECKSUM_UNNECESSARY;
1507 } else if (skb->ip_summed == CHECKSUM_COMPLETE) {
Eric Dumazetc482c562009-07-17 00:26:32 +00001508 if (!csum_tcpudp_magic(iph->saddr, iph->daddr, skb->len,
David S. Millerdb8dac22008-03-06 16:22:02 -08001509 proto, skb->csum))
1510 skb->ip_summed = CHECKSUM_UNNECESSARY;
1511 }
1512 if (!skb_csum_unnecessary(skb))
1513 skb->csum = csum_tcpudp_nofold(iph->saddr, iph->daddr,
1514 skb->len, proto, 0);
1515 /* Probably, we should checksum udp header (it should be in cache
1516 * in any case) and data in tiny packets (< rx copybreak).
1517 */
1518
1519 return 0;
1520}
1521
1522/*
1523 * All we need to do is get the socket, and then do a checksum.
1524 */
1525
Eric Dumazet645ca702008-10-29 01:41:45 -07001526int __udp4_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
David S. Millerdb8dac22008-03-06 16:22:02 -08001527 int proto)
1528{
1529 struct sock *sk;
Jesper Dangaard Brouer7b5e56f2009-02-05 15:05:45 -08001530 struct udphdr *uh;
David S. Millerdb8dac22008-03-06 16:22:02 -08001531 unsigned short ulen;
Eric Dumazetadf30902009-06-02 05:19:30 +00001532 struct rtable *rt = skb_rtable(skb);
Jesper Dangaard Brouer2783ef22009-02-06 01:59:12 -08001533 __be32 saddr, daddr;
Pavel Emelyanov02833282008-07-05 21:18:48 -07001534 struct net *net = dev_net(skb->dev);
David S. Millerdb8dac22008-03-06 16:22:02 -08001535
1536 /*
1537 * Validate the packet.
1538 */
1539 if (!pskb_may_pull(skb, sizeof(struct udphdr)))
1540 goto drop; /* No space for header. */
1541
Jesper Dangaard Brouer7b5e56f2009-02-05 15:05:45 -08001542 uh = udp_hdr(skb);
David S. Millerdb8dac22008-03-06 16:22:02 -08001543 ulen = ntohs(uh->len);
Bjørn Morkccc2d972010-05-06 03:44:34 +00001544 saddr = ip_hdr(skb)->saddr;
1545 daddr = ip_hdr(skb)->daddr;
1546
David S. Millerdb8dac22008-03-06 16:22:02 -08001547 if (ulen > skb->len)
1548 goto short_packet;
1549
1550 if (proto == IPPROTO_UDP) {
1551 /* UDP validates ulen. */
1552 if (ulen < sizeof(*uh) || pskb_trim_rcsum(skb, ulen))
1553 goto short_packet;
1554 uh = udp_hdr(skb);
1555 }
1556
1557 if (udp4_csum_init(skb, uh, proto))
1558 goto csum_error;
1559
1560 if (rt->rt_flags & (RTCF_BROADCAST|RTCF_MULTICAST))
Pavel Emelyanove3163492008-06-16 17:12:11 -07001561 return __udp4_lib_mcast_deliver(net, skb, uh,
1562 saddr, daddr, udptable);
David S. Millerdb8dac22008-03-06 16:22:02 -08001563
KOVACS Krisztian607c4aa2008-10-07 12:38:32 -07001564 sk = __udp4_lib_lookup_skb(skb, uh->source, uh->dest, udptable);
David S. Millerdb8dac22008-03-06 16:22:02 -08001565
1566 if (sk != NULL) {
Herbert Xu93821772008-09-15 11:48:46 -07001567 int ret = udp_queue_rcv_skb(sk, skb);
David S. Millerdb8dac22008-03-06 16:22:02 -08001568 sock_put(sk);
1569
1570 /* a return value > 0 means to resubmit the input, but
1571 * it wants the return to be -protocol, or 0
1572 */
1573 if (ret > 0)
1574 return -ret;
1575 return 0;
1576 }
1577
1578 if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb))
1579 goto drop;
1580 nf_reset(skb);
1581
1582 /* No socket. Drop packet silently, if checksum is wrong */
1583 if (udp_lib_checksum_complete(skb))
1584 goto csum_error;
1585
Pavel Emelyanov02833282008-07-05 21:18:48 -07001586 UDP_INC_STATS_BH(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE);
David S. Millerdb8dac22008-03-06 16:22:02 -08001587 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
1588
1589 /*
1590 * Hmm. We got an UDP packet to a port to which we
1591 * don't wanna listen. Ignore it.
1592 */
1593 kfree_skb(skb);
1594 return 0;
1595
1596short_packet:
Harvey Harrison673d57e2008-10-31 00:53:57 -07001597 LIMIT_NETDEBUG(KERN_DEBUG "UDP%s: short packet: From %pI4:%u %d/%d to %pI4:%u\n",
David S. Millerdb8dac22008-03-06 16:22:02 -08001598 proto == IPPROTO_UDPLITE ? "-Lite" : "",
Harvey Harrison673d57e2008-10-31 00:53:57 -07001599 &saddr,
David S. Millerdb8dac22008-03-06 16:22:02 -08001600 ntohs(uh->source),
1601 ulen,
1602 skb->len,
Harvey Harrison673d57e2008-10-31 00:53:57 -07001603 &daddr,
David S. Millerdb8dac22008-03-06 16:22:02 -08001604 ntohs(uh->dest));
1605 goto drop;
1606
1607csum_error:
1608 /*
1609 * RFC1122: OK. Discards the bad packet silently (as far as
1610 * the network is concerned, anyway) as per 4.1.3.4 (MUST).
1611 */
Harvey Harrison673d57e2008-10-31 00:53:57 -07001612 LIMIT_NETDEBUG(KERN_DEBUG "UDP%s: bad checksum. From %pI4:%u to %pI4:%u ulen %d\n",
David S. Millerdb8dac22008-03-06 16:22:02 -08001613 proto == IPPROTO_UDPLITE ? "-Lite" : "",
Harvey Harrison673d57e2008-10-31 00:53:57 -07001614 &saddr,
David S. Millerdb8dac22008-03-06 16:22:02 -08001615 ntohs(uh->source),
Harvey Harrison673d57e2008-10-31 00:53:57 -07001616 &daddr,
David S. Millerdb8dac22008-03-06 16:22:02 -08001617 ntohs(uh->dest),
1618 ulen);
1619drop:
Pavel Emelyanov02833282008-07-05 21:18:48 -07001620 UDP_INC_STATS_BH(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE);
David S. Millerdb8dac22008-03-06 16:22:02 -08001621 kfree_skb(skb);
1622 return 0;
1623}
1624
1625int udp_rcv(struct sk_buff *skb)
1626{
Eric Dumazet645ca702008-10-29 01:41:45 -07001627 return __udp4_lib_rcv(skb, &udp_table, IPPROTO_UDP);
David S. Millerdb8dac22008-03-06 16:22:02 -08001628}
1629
Brian Haley7d06b2e2008-06-14 17:04:49 -07001630void udp_destroy_sock(struct sock *sk)
David S. Millerdb8dac22008-03-06 16:22:02 -08001631{
Eric Dumazet8a74ad62010-05-26 19:20:18 +00001632 bool slow = lock_sock_fast(sk);
David S. Millerdb8dac22008-03-06 16:22:02 -08001633 udp_flush_pending_frames(sk);
Eric Dumazet8a74ad62010-05-26 19:20:18 +00001634 unlock_sock_fast(sk, slow);
David S. Millerdb8dac22008-03-06 16:22:02 -08001635}
1636
Linus Torvalds1da177e2005-04-16 15:20:36 -07001637/*
1638 * Socket option code for UDP
1639 */
Gerrit Renker4c0a6cb2006-11-27 09:29:59 -08001640int udp_lib_setsockopt(struct sock *sk, int level, int optname,
David S. Millerb7058842009-09-30 16:12:20 -07001641 char __user *optval, unsigned int optlen,
Gerrit Renker4c0a6cb2006-11-27 09:29:59 -08001642 int (*push_pending_frames)(struct sock *))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001643{
1644 struct udp_sock *up = udp_sk(sk);
1645 int val;
1646 int err = 0;
Wang Chenb2bf1e22007-12-03 22:34:16 +11001647 int is_udplite = IS_UDPLITE(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001648
Eric Dumazetc482c562009-07-17 00:26:32 +00001649 if (optlen < sizeof(int))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001650 return -EINVAL;
1651
1652 if (get_user(val, (int __user *)optval))
1653 return -EFAULT;
1654
Stephen Hemminger6516c652007-03-08 20:41:55 -08001655 switch (optname) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001656 case UDP_CORK:
1657 if (val != 0) {
1658 up->corkflag = 1;
1659 } else {
1660 up->corkflag = 0;
1661 lock_sock(sk);
Gerrit Renker4c0a6cb2006-11-27 09:29:59 -08001662 (*push_pending_frames)(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001663 release_sock(sk);
1664 }
1665 break;
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +09001666
Linus Torvalds1da177e2005-04-16 15:20:36 -07001667 case UDP_ENCAP:
1668 switch (val) {
1669 case 0:
1670 case UDP_ENCAP_ESPINUDP:
1671 case UDP_ENCAP_ESPINUDP_NON_IKE:
James Chapman067b2072007-07-05 17:08:05 -07001672 up->encap_rcv = xfrm4_udp_encap_rcv;
1673 /* FALLTHROUGH */
James Chapman342f0232007-06-27 15:37:46 -07001674 case UDP_ENCAP_L2TPINUDP:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001675 up->encap_type = val;
1676 break;
1677 default:
1678 err = -ENOPROTOOPT;
1679 break;
1680 }
1681 break;
1682
Gerrit Renkerba4e58e2006-11-27 11:10:57 -08001683 /*
1684 * UDP-Lite's partial checksum coverage (RFC 3828).
1685 */
1686 /* The sender sets actual checksum coverage length via this option.
1687 * The case coverage > packet length is handled by send module. */
1688 case UDPLITE_SEND_CSCOV:
Wang Chenb2bf1e22007-12-03 22:34:16 +11001689 if (!is_udplite) /* Disable the option on UDP sockets */
Gerrit Renkerba4e58e2006-11-27 11:10:57 -08001690 return -ENOPROTOOPT;
1691 if (val != 0 && val < 8) /* Illegal coverage: use default (8) */
1692 val = 8;
Gerrit Renker47112e22008-07-21 13:35:08 -07001693 else if (val > USHORT_MAX)
1694 val = USHORT_MAX;
Gerrit Renkerba4e58e2006-11-27 11:10:57 -08001695 up->pcslen = val;
1696 up->pcflag |= UDPLITE_SEND_CC;
1697 break;
1698
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +09001699 /* The receiver specifies a minimum checksum coverage value. To make
1700 * sense, this should be set to at least 8 (as done below). If zero is
Gerrit Renkerba4e58e2006-11-27 11:10:57 -08001701 * used, this again means full checksum coverage. */
1702 case UDPLITE_RECV_CSCOV:
Wang Chenb2bf1e22007-12-03 22:34:16 +11001703 if (!is_udplite) /* Disable the option on UDP sockets */
Gerrit Renkerba4e58e2006-11-27 11:10:57 -08001704 return -ENOPROTOOPT;
1705 if (val != 0 && val < 8) /* Avoid silly minimal values. */
1706 val = 8;
Gerrit Renker47112e22008-07-21 13:35:08 -07001707 else if (val > USHORT_MAX)
1708 val = USHORT_MAX;
Gerrit Renkerba4e58e2006-11-27 11:10:57 -08001709 up->pcrlen = val;
1710 up->pcflag |= UDPLITE_RECV_CC;
1711 break;
1712
Linus Torvalds1da177e2005-04-16 15:20:36 -07001713 default:
1714 err = -ENOPROTOOPT;
1715 break;
Stephen Hemminger6516c652007-03-08 20:41:55 -08001716 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001717
1718 return err;
1719}
Eric Dumazetc482c562009-07-17 00:26:32 +00001720EXPORT_SYMBOL(udp_lib_setsockopt);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001721
David S. Millerdb8dac22008-03-06 16:22:02 -08001722int udp_setsockopt(struct sock *sk, int level, int optname,
David S. Millerb7058842009-09-30 16:12:20 -07001723 char __user *optval, unsigned int optlen)
David S. Millerdb8dac22008-03-06 16:22:02 -08001724{
1725 if (level == SOL_UDP || level == SOL_UDPLITE)
1726 return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1727 udp_push_pending_frames);
1728 return ip_setsockopt(sk, level, optname, optval, optlen);
1729}
1730
1731#ifdef CONFIG_COMPAT
1732int compat_udp_setsockopt(struct sock *sk, int level, int optname,
David S. Millerb7058842009-09-30 16:12:20 -07001733 char __user *optval, unsigned int optlen)
David S. Millerdb8dac22008-03-06 16:22:02 -08001734{
1735 if (level == SOL_UDP || level == SOL_UDPLITE)
1736 return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1737 udp_push_pending_frames);
1738 return compat_ip_setsockopt(sk, level, optname, optval, optlen);
1739}
1740#endif
1741
Gerrit Renker4c0a6cb2006-11-27 09:29:59 -08001742int udp_lib_getsockopt(struct sock *sk, int level, int optname,
1743 char __user *optval, int __user *optlen)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001744{
1745 struct udp_sock *up = udp_sk(sk);
1746 int val, len;
1747
Eric Dumazetc482c562009-07-17 00:26:32 +00001748 if (get_user(len, optlen))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001749 return -EFAULT;
1750
1751 len = min_t(unsigned int, len, sizeof(int));
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +09001752
Stephen Hemminger6516c652007-03-08 20:41:55 -08001753 if (len < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001754 return -EINVAL;
1755
Stephen Hemminger6516c652007-03-08 20:41:55 -08001756 switch (optname) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001757 case UDP_CORK:
1758 val = up->corkflag;
1759 break;
1760
1761 case UDP_ENCAP:
1762 val = up->encap_type;
1763 break;
1764
Gerrit Renkerba4e58e2006-11-27 11:10:57 -08001765 /* The following two cannot be changed on UDP sockets, the return is
1766 * always 0 (which corresponds to the full checksum coverage of UDP). */
1767 case UDPLITE_SEND_CSCOV:
1768 val = up->pcslen;
1769 break;
1770
1771 case UDPLITE_RECV_CSCOV:
1772 val = up->pcrlen;
1773 break;
1774
Linus Torvalds1da177e2005-04-16 15:20:36 -07001775 default:
1776 return -ENOPROTOOPT;
Stephen Hemminger6516c652007-03-08 20:41:55 -08001777 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001778
Stephen Hemminger6516c652007-03-08 20:41:55 -08001779 if (put_user(len, optlen))
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +09001780 return -EFAULT;
Eric Dumazetc482c562009-07-17 00:26:32 +00001781 if (copy_to_user(optval, &val, len))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001782 return -EFAULT;
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +09001783 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001784}
Eric Dumazetc482c562009-07-17 00:26:32 +00001785EXPORT_SYMBOL(udp_lib_getsockopt);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001786
David S. Millerdb8dac22008-03-06 16:22:02 -08001787int udp_getsockopt(struct sock *sk, int level, int optname,
1788 char __user *optval, int __user *optlen)
1789{
1790 if (level == SOL_UDP || level == SOL_UDPLITE)
1791 return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1792 return ip_getsockopt(sk, level, optname, optval, optlen);
1793}
1794
1795#ifdef CONFIG_COMPAT
1796int compat_udp_getsockopt(struct sock *sk, int level, int optname,
1797 char __user *optval, int __user *optlen)
1798{
1799 if (level == SOL_UDP || level == SOL_UDPLITE)
1800 return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1801 return compat_ip_getsockopt(sk, level, optname, optval, optlen);
1802}
1803#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07001804/**
1805 * udp_poll - wait for a UDP event.
1806 * @file - file struct
1807 * @sock - socket
1808 * @wait - poll table
1809 *
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +09001810 * This is same as datagram poll, except for the special case of
Linus Torvalds1da177e2005-04-16 15:20:36 -07001811 * blocking sockets. If application is using a blocking fd
1812 * and a packet with checksum error is in the queue;
1813 * then it could get return from select indicating data available
1814 * but then block when reading it. Add special case code
1815 * to work around these arguably broken applications.
1816 */
1817unsigned int udp_poll(struct file *file, struct socket *sock, poll_table *wait)
1818{
1819 unsigned int mask = datagram_poll(file, sock, wait);
1820 struct sock *sk = sock->sk;
Gerrit Renkerba4e58e2006-11-27 11:10:57 -08001821
Linus Torvalds1da177e2005-04-16 15:20:36 -07001822 /* Check for false positives due to checksum errors */
Eric Dumazet85584672009-10-09 04:43:40 +00001823 if ((mask & POLLRDNORM) && !(file->f_flags & O_NONBLOCK) &&
1824 !(sk->sk_shutdown & RCV_SHUTDOWN) && !first_packet_length(sk))
1825 mask &= ~(POLLIN | POLLRDNORM);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001826
1827 return mask;
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +09001828
Linus Torvalds1da177e2005-04-16 15:20:36 -07001829}
Eric Dumazetc482c562009-07-17 00:26:32 +00001830EXPORT_SYMBOL(udp_poll);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001831
David S. Millerdb8dac22008-03-06 16:22:02 -08001832struct proto udp_prot = {
1833 .name = "UDP",
1834 .owner = THIS_MODULE,
1835 .close = udp_lib_close,
1836 .connect = ip4_datagram_connect,
1837 .disconnect = udp_disconnect,
1838 .ioctl = udp_ioctl,
1839 .destroy = udp_destroy_sock,
1840 .setsockopt = udp_setsockopt,
1841 .getsockopt = udp_getsockopt,
1842 .sendmsg = udp_sendmsg,
1843 .recvmsg = udp_recvmsg,
1844 .sendpage = udp_sendpage,
Herbert Xu93821772008-09-15 11:48:46 -07001845 .backlog_rcv = __udp_queue_rcv_skb,
David S. Millerdb8dac22008-03-06 16:22:02 -08001846 .hash = udp_lib_hash,
1847 .unhash = udp_lib_unhash,
1848 .get_port = udp_v4_get_port,
1849 .memory_allocated = &udp_memory_allocated,
1850 .sysctl_mem = sysctl_udp_mem,
1851 .sysctl_wmem = &sysctl_udp_wmem_min,
1852 .sysctl_rmem = &sysctl_udp_rmem_min,
1853 .obj_size = sizeof(struct udp_sock),
Eric Dumazet271b72c2008-10-29 02:11:14 -07001854 .slab_flags = SLAB_DESTROY_BY_RCU,
Eric Dumazet645ca702008-10-29 01:41:45 -07001855 .h.udp_table = &udp_table,
David S. Millerdb8dac22008-03-06 16:22:02 -08001856#ifdef CONFIG_COMPAT
1857 .compat_setsockopt = compat_udp_setsockopt,
1858 .compat_getsockopt = compat_udp_getsockopt,
1859#endif
David S. Millerdb8dac22008-03-06 16:22:02 -08001860};
Eric Dumazetc482c562009-07-17 00:26:32 +00001861EXPORT_SYMBOL(udp_prot);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001862
1863/* ------------------------------------------------------------------------ */
1864#ifdef CONFIG_PROC_FS
1865
Eric Dumazet645ca702008-10-29 01:41:45 -07001866static struct sock *udp_get_first(struct seq_file *seq, int start)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001867{
1868 struct sock *sk;
1869 struct udp_iter_state *state = seq->private;
Denis V. Lunev6f191ef2008-03-28 18:23:33 -07001870 struct net *net = seq_file_net(seq);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001871
Eric Dumazetf86dcc52009-10-07 00:37:59 +00001872 for (state->bucket = start; state->bucket <= state->udp_table->mask;
1873 ++state->bucket) {
Eric Dumazet88ab1932008-11-16 19:39:21 -08001874 struct hlist_nulls_node *node;
Eric Dumazet645ca702008-10-29 01:41:45 -07001875 struct udp_hslot *hslot = &state->udp_table->hash[state->bucket];
Eric Dumazetf86dcc52009-10-07 00:37:59 +00001876
1877 if (hlist_nulls_empty(&hslot->head))
1878 continue;
1879
Eric Dumazet645ca702008-10-29 01:41:45 -07001880 spin_lock_bh(&hslot->lock);
Eric Dumazet88ab1932008-11-16 19:39:21 -08001881 sk_nulls_for_each(sk, node, &hslot->head) {
YOSHIFUJI Hideaki878628f2008-03-26 03:57:35 +09001882 if (!net_eq(sock_net(sk), net))
Daniel Lezcanoa91275e2008-03-21 04:11:58 -07001883 continue;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001884 if (sk->sk_family == state->family)
1885 goto found;
1886 }
Eric Dumazet645ca702008-10-29 01:41:45 -07001887 spin_unlock_bh(&hslot->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001888 }
1889 sk = NULL;
1890found:
1891 return sk;
1892}
1893
1894static struct sock *udp_get_next(struct seq_file *seq, struct sock *sk)
1895{
1896 struct udp_iter_state *state = seq->private;
Denis V. Lunev6f191ef2008-03-28 18:23:33 -07001897 struct net *net = seq_file_net(seq);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001898
1899 do {
Eric Dumazet88ab1932008-11-16 19:39:21 -08001900 sk = sk_nulls_next(sk);
YOSHIFUJI Hideaki878628f2008-03-26 03:57:35 +09001901 } while (sk && (!net_eq(sock_net(sk), net) || sk->sk_family != state->family));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001902
Eric Dumazet645ca702008-10-29 01:41:45 -07001903 if (!sk) {
Eric Dumazetf86dcc52009-10-07 00:37:59 +00001904 if (state->bucket <= state->udp_table->mask)
Vitaly Mayatskikh30842f22009-03-23 15:22:33 -07001905 spin_unlock_bh(&state->udp_table->hash[state->bucket].lock);
Eric Dumazet645ca702008-10-29 01:41:45 -07001906 return udp_get_first(seq, state->bucket + 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001907 }
1908 return sk;
1909}
1910
1911static struct sock *udp_get_idx(struct seq_file *seq, loff_t pos)
1912{
Eric Dumazet645ca702008-10-29 01:41:45 -07001913 struct sock *sk = udp_get_first(seq, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001914
1915 if (sk)
Stephen Hemminger6516c652007-03-08 20:41:55 -08001916 while (pos && (sk = udp_get_next(seq, sk)) != NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001917 --pos;
1918 return pos ? NULL : sk;
1919}
1920
1921static void *udp_seq_start(struct seq_file *seq, loff_t *pos)
1922{
Vitaly Mayatskikh30842f22009-03-23 15:22:33 -07001923 struct udp_iter_state *state = seq->private;
Eric Dumazetf86dcc52009-10-07 00:37:59 +00001924 state->bucket = MAX_UDP_PORTS;
Vitaly Mayatskikh30842f22009-03-23 15:22:33 -07001925
YOSHIFUJI Hideakib50660f2008-03-31 19:38:15 -07001926 return *pos ? udp_get_idx(seq, *pos-1) : SEQ_START_TOKEN;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001927}
1928
1929static void *udp_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1930{
1931 struct sock *sk;
1932
YOSHIFUJI Hideakib50660f2008-03-31 19:38:15 -07001933 if (v == SEQ_START_TOKEN)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001934 sk = udp_get_idx(seq, 0);
1935 else
1936 sk = udp_get_next(seq, v);
1937
1938 ++*pos;
1939 return sk;
1940}
1941
1942static void udp_seq_stop(struct seq_file *seq, void *v)
1943{
Eric Dumazet645ca702008-10-29 01:41:45 -07001944 struct udp_iter_state *state = seq->private;
1945
Eric Dumazetf86dcc52009-10-07 00:37:59 +00001946 if (state->bucket <= state->udp_table->mask)
Eric Dumazet645ca702008-10-29 01:41:45 -07001947 spin_unlock_bh(&state->udp_table->hash[state->bucket].lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001948}
1949
1950static int udp_seq_open(struct inode *inode, struct file *file)
1951{
1952 struct udp_seq_afinfo *afinfo = PDE(inode)->data;
Denis V. Luneva2be75c2008-03-28 18:25:06 -07001953 struct udp_iter_state *s;
1954 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001955
Denis V. Luneva2be75c2008-03-28 18:25:06 -07001956 err = seq_open_net(inode, file, &afinfo->seq_ops,
1957 sizeof(struct udp_iter_state));
1958 if (err < 0)
1959 return err;
Daniel Lezcanoa91275e2008-03-21 04:11:58 -07001960
Denis V. Luneva2be75c2008-03-28 18:25:06 -07001961 s = ((struct seq_file *)file->private_data)->private;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001962 s->family = afinfo->family;
Eric Dumazet645ca702008-10-29 01:41:45 -07001963 s->udp_table = afinfo->udp_table;
Denis V. Luneva2be75c2008-03-28 18:25:06 -07001964 return err;
Daniel Lezcanoa91275e2008-03-21 04:11:58 -07001965}
1966
Linus Torvalds1da177e2005-04-16 15:20:36 -07001967/* ------------------------------------------------------------------------ */
Daniel Lezcano0c96d8c2008-03-21 04:14:17 -07001968int udp_proc_register(struct net *net, struct udp_seq_afinfo *afinfo)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001969{
1970 struct proc_dir_entry *p;
1971 int rc = 0;
1972
Denis V. Lunev3ba94412008-03-28 18:25:32 -07001973 afinfo->seq_fops.open = udp_seq_open;
1974 afinfo->seq_fops.read = seq_read;
1975 afinfo->seq_fops.llseek = seq_lseek;
1976 afinfo->seq_fops.release = seq_release_net;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001977
Denis V. Lunevdda61922008-03-28 18:24:26 -07001978 afinfo->seq_ops.start = udp_seq_start;
1979 afinfo->seq_ops.next = udp_seq_next;
1980 afinfo->seq_ops.stop = udp_seq_stop;
1981
Denis V. Lunev84841c32008-05-02 04:10:08 -07001982 p = proc_create_data(afinfo->name, S_IRUGO, net->proc_net,
1983 &afinfo->seq_fops, afinfo);
1984 if (!p)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001985 rc = -ENOMEM;
1986 return rc;
1987}
Eric Dumazetc482c562009-07-17 00:26:32 +00001988EXPORT_SYMBOL(udp_proc_register);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001989
Daniel Lezcano0c96d8c2008-03-21 04:14:17 -07001990void udp_proc_unregister(struct net *net, struct udp_seq_afinfo *afinfo)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001991{
Daniel Lezcano0c96d8c2008-03-21 04:14:17 -07001992 proc_net_remove(net, afinfo->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001993}
Eric Dumazetc482c562009-07-17 00:26:32 +00001994EXPORT_SYMBOL(udp_proc_unregister);
David S. Millerdb8dac22008-03-06 16:22:02 -08001995
1996/* ------------------------------------------------------------------------ */
Pavel Emelyanov5e659e42008-04-24 01:02:16 -07001997static void udp4_format_sock(struct sock *sp, struct seq_file *f,
1998 int bucket, int *len)
David S. Millerdb8dac22008-03-06 16:22:02 -08001999{
2000 struct inet_sock *inet = inet_sk(sp);
Eric Dumazetc720c7e2009-10-15 06:30:45 +00002001 __be32 dest = inet->inet_daddr;
2002 __be32 src = inet->inet_rcv_saddr;
2003 __u16 destp = ntohs(inet->inet_dport);
2004 __u16 srcp = ntohs(inet->inet_sport);
David S. Millerdb8dac22008-03-06 16:22:02 -08002005
Eric Dumazetf86dcc52009-10-07 00:37:59 +00002006 seq_printf(f, "%5d: %08X:%04X %08X:%04X"
Eric Dumazetcb61cb92008-06-17 21:04:56 -07002007 " %02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %p %d%n",
David S. Millerdb8dac22008-03-06 16:22:02 -08002008 bucket, src, srcp, dest, destp, sp->sk_state,
Eric Dumazet31e6d362009-06-17 19:05:41 -07002009 sk_wmem_alloc_get(sp),
2010 sk_rmem_alloc_get(sp),
David S. Millerdb8dac22008-03-06 16:22:02 -08002011 0, 0L, 0, sock_i_uid(sp), 0, sock_i_ino(sp),
Eric Dumazetcb61cb92008-06-17 21:04:56 -07002012 atomic_read(&sp->sk_refcnt), sp,
2013 atomic_read(&sp->sk_drops), len);
David S. Millerdb8dac22008-03-06 16:22:02 -08002014}
2015
2016int udp4_seq_show(struct seq_file *seq, void *v)
2017{
2018 if (v == SEQ_START_TOKEN)
2019 seq_printf(seq, "%-127s\n",
2020 " sl local_address rem_address st tx_queue "
2021 "rx_queue tr tm->when retrnsmt uid timeout "
Eric Dumazetcb61cb92008-06-17 21:04:56 -07002022 "inode ref pointer drops");
David S. Millerdb8dac22008-03-06 16:22:02 -08002023 else {
David S. Millerdb8dac22008-03-06 16:22:02 -08002024 struct udp_iter_state *state = seq->private;
Pavel Emelyanov5e659e42008-04-24 01:02:16 -07002025 int len;
David S. Millerdb8dac22008-03-06 16:22:02 -08002026
Pavel Emelyanov5e659e42008-04-24 01:02:16 -07002027 udp4_format_sock(v, seq, state->bucket, &len);
Eric Dumazetc482c562009-07-17 00:26:32 +00002028 seq_printf(seq, "%*s\n", 127 - len, "");
David S. Millerdb8dac22008-03-06 16:22:02 -08002029 }
2030 return 0;
2031}
2032
2033/* ------------------------------------------------------------------------ */
David S. Millerdb8dac22008-03-06 16:22:02 -08002034static struct udp_seq_afinfo udp4_seq_afinfo = {
David S. Millerdb8dac22008-03-06 16:22:02 -08002035 .name = "udp",
2036 .family = AF_INET,
Eric Dumazet645ca702008-10-29 01:41:45 -07002037 .udp_table = &udp_table,
Denis V. Lunev4ad96d32008-03-28 18:25:53 -07002038 .seq_fops = {
2039 .owner = THIS_MODULE,
2040 },
Denis V. Lunevdda61922008-03-28 18:24:26 -07002041 .seq_ops = {
2042 .show = udp4_seq_show,
2043 },
David S. Millerdb8dac22008-03-06 16:22:02 -08002044};
2045
Alexey Dobriyan2c8c1e72010-01-17 03:35:32 +00002046static int __net_init udp4_proc_init_net(struct net *net)
Pavel Emelyanov15439fe2008-03-24 14:53:49 -07002047{
2048 return udp_proc_register(net, &udp4_seq_afinfo);
2049}
2050
Alexey Dobriyan2c8c1e72010-01-17 03:35:32 +00002051static void __net_exit udp4_proc_exit_net(struct net *net)
Pavel Emelyanov15439fe2008-03-24 14:53:49 -07002052{
2053 udp_proc_unregister(net, &udp4_seq_afinfo);
2054}
2055
2056static struct pernet_operations udp4_net_ops = {
2057 .init = udp4_proc_init_net,
2058 .exit = udp4_proc_exit_net,
2059};
2060
David S. Millerdb8dac22008-03-06 16:22:02 -08002061int __init udp4_proc_init(void)
2062{
Pavel Emelyanov15439fe2008-03-24 14:53:49 -07002063 return register_pernet_subsys(&udp4_net_ops);
David S. Millerdb8dac22008-03-06 16:22:02 -08002064}
2065
2066void udp4_proc_exit(void)
2067{
Pavel Emelyanov15439fe2008-03-24 14:53:49 -07002068 unregister_pernet_subsys(&udp4_net_ops);
David S. Millerdb8dac22008-03-06 16:22:02 -08002069}
Linus Torvalds1da177e2005-04-16 15:20:36 -07002070#endif /* CONFIG_PROC_FS */
2071
Eric Dumazetf86dcc52009-10-07 00:37:59 +00002072static __initdata unsigned long uhash_entries;
2073static int __init set_uhash_entries(char *str)
Eric Dumazet645ca702008-10-29 01:41:45 -07002074{
Eric Dumazetf86dcc52009-10-07 00:37:59 +00002075 if (!str)
2076 return 0;
2077 uhash_entries = simple_strtoul(str, &str, 0);
2078 if (uhash_entries && uhash_entries < UDP_HTABLE_SIZE_MIN)
2079 uhash_entries = UDP_HTABLE_SIZE_MIN;
2080 return 1;
2081}
2082__setup("uhash_entries=", set_uhash_entries);
Eric Dumazet645ca702008-10-29 01:41:45 -07002083
Eric Dumazetf86dcc52009-10-07 00:37:59 +00002084void __init udp_table_init(struct udp_table *table, const char *name)
2085{
2086 unsigned int i;
2087
2088 if (!CONFIG_BASE_SMALL)
2089 table->hash = alloc_large_system_hash(name,
Eric Dumazet512615b2009-11-08 10:17:58 +00002090 2 * sizeof(struct udp_hslot),
Eric Dumazetf86dcc52009-10-07 00:37:59 +00002091 uhash_entries,
2092 21, /* one slot per 2 MB */
2093 0,
2094 &table->log,
2095 &table->mask,
2096 64 * 1024);
2097 /*
2098 * Make sure hash table has the minimum size
2099 */
2100 if (CONFIG_BASE_SMALL || table->mask < UDP_HTABLE_SIZE_MIN - 1) {
2101 table->hash = kmalloc(UDP_HTABLE_SIZE_MIN *
Eric Dumazet512615b2009-11-08 10:17:58 +00002102 2 * sizeof(struct udp_hslot), GFP_KERNEL);
Eric Dumazetf86dcc52009-10-07 00:37:59 +00002103 if (!table->hash)
2104 panic(name);
2105 table->log = ilog2(UDP_HTABLE_SIZE_MIN);
2106 table->mask = UDP_HTABLE_SIZE_MIN - 1;
2107 }
Eric Dumazet512615b2009-11-08 10:17:58 +00002108 table->hash2 = table->hash + (table->mask + 1);
Eric Dumazetf86dcc52009-10-07 00:37:59 +00002109 for (i = 0; i <= table->mask; i++) {
Eric Dumazet88ab1932008-11-16 19:39:21 -08002110 INIT_HLIST_NULLS_HEAD(&table->hash[i].head, i);
Eric Dumazetfdcc8aa92009-11-08 10:17:05 +00002111 table->hash[i].count = 0;
Eric Dumazet645ca702008-10-29 01:41:45 -07002112 spin_lock_init(&table->hash[i].lock);
2113 }
Eric Dumazet512615b2009-11-08 10:17:58 +00002114 for (i = 0; i <= table->mask; i++) {
2115 INIT_HLIST_NULLS_HEAD(&table->hash2[i].head, i);
2116 table->hash2[i].count = 0;
2117 spin_lock_init(&table->hash2[i].lock);
2118 }
Eric Dumazet645ca702008-10-29 01:41:45 -07002119}
2120
Hideo Aoki95766ff2007-12-31 00:29:24 -08002121void __init udp_init(void)
2122{
Eric Dumazet8203efb2008-10-29 02:32:32 -07002123 unsigned long nr_pages, limit;
Hideo Aoki95766ff2007-12-31 00:29:24 -08002124
Eric Dumazetf86dcc52009-10-07 00:37:59 +00002125 udp_table_init(&udp_table, "UDP");
Hideo Aoki95766ff2007-12-31 00:29:24 -08002126 /* Set the pressure threshold up by the same strategy of TCP. It is a
2127 * fraction of global memory that is up to 1/2 at 256 MB, decreasing
2128 * toward zero with the amount of memory, with a floor of 128 pages.
2129 */
Eric Dumazet8203efb2008-10-29 02:32:32 -07002130 nr_pages = totalram_pages - totalhigh_pages;
2131 limit = min(nr_pages, 1UL<<(28-PAGE_SHIFT)) >> (20-PAGE_SHIFT);
2132 limit = (limit * (nr_pages >> (20-PAGE_SHIFT))) >> (PAGE_SHIFT-11);
Hideo Aoki95766ff2007-12-31 00:29:24 -08002133 limit = max(limit, 128UL);
2134 sysctl_udp_mem[0] = limit / 4 * 3;
2135 sysctl_udp_mem[1] = limit;
2136 sysctl_udp_mem[2] = sysctl_udp_mem[0] * 2;
2137
2138 sysctl_udp_rmem_min = SK_MEM_QUANTUM;
2139 sysctl_udp_wmem_min = SK_MEM_QUANTUM;
2140}
2141
Sridhar Samudralad7ca4cc2009-07-09 08:09:47 +00002142int udp4_ufo_send_check(struct sk_buff *skb)
2143{
2144 const struct iphdr *iph;
2145 struct udphdr *uh;
2146
2147 if (!pskb_may_pull(skb, sizeof(*uh)))
2148 return -EINVAL;
2149
2150 iph = ip_hdr(skb);
2151 uh = udp_hdr(skb);
2152
2153 uh->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr, skb->len,
2154 IPPROTO_UDP, 0);
2155 skb->csum_start = skb_transport_header(skb) - skb->head;
2156 skb->csum_offset = offsetof(struct udphdr, check);
2157 skb->ip_summed = CHECKSUM_PARTIAL;
2158 return 0;
2159}
2160
2161struct sk_buff *udp4_ufo_fragment(struct sk_buff *skb, int features)
2162{
2163 struct sk_buff *segs = ERR_PTR(-EINVAL);
2164 unsigned int mss;
2165 int offset;
2166 __wsum csum;
2167
2168 mss = skb_shinfo(skb)->gso_size;
2169 if (unlikely(skb->len <= mss))
2170 goto out;
2171
2172 if (skb_gso_ok(skb, features | NETIF_F_GSO_ROBUST)) {
2173 /* Packet is from an untrusted source, reset gso_segs. */
2174 int type = skb_shinfo(skb)->gso_type;
2175
2176 if (unlikely(type & ~(SKB_GSO_UDP | SKB_GSO_DODGY) ||
2177 !(type & (SKB_GSO_UDP))))
2178 goto out;
2179
2180 skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(skb->len, mss);
2181
2182 segs = NULL;
2183 goto out;
2184 }
2185
2186 /* Do software UFO. Complete and fill in the UDP checksum as HW cannot
2187 * do checksum of UDP packets sent as multiple IP fragments.
2188 */
2189 offset = skb->csum_start - skb_headroom(skb);
Eric Dumazetc482c562009-07-17 00:26:32 +00002190 csum = skb_checksum(skb, offset, skb->len - offset, 0);
Sridhar Samudralad7ca4cc2009-07-09 08:09:47 +00002191 offset += skb->csum_offset;
2192 *(__sum16 *)(skb->data + offset) = csum_fold(csum);
2193 skb->ip_summed = CHECKSUM_NONE;
2194
2195 /* Fragment the skb. IP headers of the fragments are updated in
2196 * inet_gso_segment()
2197 */
2198 segs = skb_segment(skb, features);
2199out:
2200 return segs;
2201}
2202