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Revert "af_packet: add interframe drop cmsg (v6)"
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / ipv4 / udp.c
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 #include <asm/system.h>
81 #include <asm/uaccess.h>
82 #include <asm/ioctls.h>
83 #include <linux/bootmem.h>
84 #include <linux/highmem.h>
85 #include <linux/swap.h>
86 #include <linux/types.h>
87 #include <linux/fcntl.h>
88 #include <linux/module.h>
89 #include <linux/socket.h>
90 #include <linux/sockios.h>
91 #include <linux/igmp.h>
92 #include <linux/in.h>
93 #include <linux/errno.h>
94 #include <linux/timer.h>
95 #include <linux/mm.h>
96 #include <linux/inet.h>
97 #include <linux/netdevice.h>
98 #include <net/tcp_states.h>
99 #include <linux/skbuff.h>
100 #include <linux/proc_fs.h>
101 #include <linux/seq_file.h>
102 #include <net/net_namespace.h>
103 #include <net/icmp.h>
104 #include <net/route.h>
105 #include <net/checksum.h>
106 #include <net/xfrm.h>
107 #include "udp_impl.h"
108
109 struct udp_table udp_table __read_mostly;
110 EXPORT_SYMBOL(udp_table);
111
112 int sysctl_udp_mem[3] __read_mostly;
113 EXPORT_SYMBOL(sysctl_udp_mem);
114
115 int sysctl_udp_rmem_min __read_mostly;
116 EXPORT_SYMBOL(sysctl_udp_rmem_min);
117
118 int sysctl_udp_wmem_min __read_mostly;
119 EXPORT_SYMBOL(sysctl_udp_wmem_min);
120
121 atomic_t udp_memory_allocated;
122 EXPORT_SYMBOL(udp_memory_allocated);
123
124 #define MAX_UDP_PORTS 65536
125 #define PORTS_PER_CHAIN (MAX_UDP_PORTS / UDP_HTABLE_SIZE_MIN)
126
127 static int udp_lib_lport_inuse(struct net *net, __u16 num,
128 const struct udp_hslot *hslot,
129 unsigned long *bitmap,
130 struct sock *sk,
131 int (*saddr_comp)(const struct sock *sk1,
132 const struct sock *sk2),
133 unsigned int log)
134 {
135 struct sock *sk2;
136 struct hlist_nulls_node *node;
137
138 sk_nulls_for_each(sk2, node, &hslot->head)
139 if (net_eq(sock_net(sk2), net) &&
140 sk2 != sk &&
141 (bitmap || sk2->sk_hash == num) &&
142 (!sk2->sk_reuse || !sk->sk_reuse) &&
143 (!sk2->sk_bound_dev_if || !sk->sk_bound_dev_if
144 || sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
145 (*saddr_comp)(sk, sk2)) {
146 if (bitmap)
147 __set_bit(sk2->sk_hash >> log, bitmap);
148 else
149 return 1;
150 }
151 return 0;
152 }
153
154 /**
155 * udp_lib_get_port - UDP/-Lite port lookup for IPv4 and IPv6
156 *
157 * @sk: socket struct in question
158 * @snum: port number to look up
159 * @saddr_comp: AF-dependent comparison of bound local IP addresses
160 */
161 int udp_lib_get_port(struct sock *sk, unsigned short snum,
162 int (*saddr_comp)(const struct sock *sk1,
163 const struct sock *sk2))
164 {
165 struct udp_hslot *hslot;
166 struct udp_table *udptable = sk->sk_prot->h.udp_table;
167 int error = 1;
168 struct net *net = sock_net(sk);
169
170 if (!snum) {
171 int low, high, remaining;
172 unsigned rand;
173 unsigned short first, last;
174 DECLARE_BITMAP(bitmap, PORTS_PER_CHAIN);
175
176 inet_get_local_port_range(&low, &high);
177 remaining = (high - low) + 1;
178
179 rand = net_random();
180 first = (((u64)rand * remaining) >> 32) + low;
181 /*
182 * force rand to be an odd multiple of UDP_HTABLE_SIZE
183 */
184 rand = (rand | 1) * (udptable->mask + 1);
185 for (last = first + udptable->mask + 1;
186 first != last;
187 first++) {
188 hslot = udp_hashslot(udptable, net, first);
189 bitmap_zero(bitmap, PORTS_PER_CHAIN);
190 spin_lock_bh(&hslot->lock);
191 udp_lib_lport_inuse(net, snum, hslot, bitmap, sk,
192 saddr_comp, udptable->log);
193
194 snum = first;
195 /*
196 * Iterate on all possible values of snum for this hash.
197 * Using steps of an odd multiple of UDP_HTABLE_SIZE
198 * give us randomization and full range coverage.
199 */
200 do {
201 if (low <= snum && snum <= high &&
202 !test_bit(snum >> udptable->log, bitmap))
203 goto found;
204 snum += rand;
205 } while (snum != first);
206 spin_unlock_bh(&hslot->lock);
207 }
208 goto fail;
209 } else {
210 hslot = udp_hashslot(udptable, net, snum);
211 spin_lock_bh(&hslot->lock);
212 if (udp_lib_lport_inuse(net, snum, hslot, NULL, sk,
213 saddr_comp, 0))
214 goto fail_unlock;
215 }
216 found:
217 inet_sk(sk)->num = snum;
218 sk->sk_hash = snum;
219 if (sk_unhashed(sk)) {
220 sk_nulls_add_node_rcu(sk, &hslot->head);
221 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
222 }
223 error = 0;
224 fail_unlock:
225 spin_unlock_bh(&hslot->lock);
226 fail:
227 return error;
228 }
229 EXPORT_SYMBOL(udp_lib_get_port);
230
231 static int ipv4_rcv_saddr_equal(const struct sock *sk1, const struct sock *sk2)
232 {
233 struct inet_sock *inet1 = inet_sk(sk1), *inet2 = inet_sk(sk2);
234
235 return (!ipv6_only_sock(sk2) &&
236 (!inet1->rcv_saddr || !inet2->rcv_saddr ||
237 inet1->rcv_saddr == inet2->rcv_saddr));
238 }
239
240 int udp_v4_get_port(struct sock *sk, unsigned short snum)
241 {
242 return udp_lib_get_port(sk, snum, ipv4_rcv_saddr_equal);
243 }
244
245 static inline int compute_score(struct sock *sk, struct net *net, __be32 saddr,
246 unsigned short hnum,
247 __be16 sport, __be32 daddr, __be16 dport, int dif)
248 {
249 int score = -1;
250
251 if (net_eq(sock_net(sk), net) && sk->sk_hash == hnum &&
252 !ipv6_only_sock(sk)) {
253 struct inet_sock *inet = inet_sk(sk);
254
255 score = (sk->sk_family == PF_INET ? 1 : 0);
256 if (inet->rcv_saddr) {
257 if (inet->rcv_saddr != daddr)
258 return -1;
259 score += 2;
260 }
261 if (inet->daddr) {
262 if (inet->daddr != saddr)
263 return -1;
264 score += 2;
265 }
266 if (inet->dport) {
267 if (inet->dport != sport)
268 return -1;
269 score += 2;
270 }
271 if (sk->sk_bound_dev_if) {
272 if (sk->sk_bound_dev_if != dif)
273 return -1;
274 score += 2;
275 }
276 }
277 return score;
278 }
279
280 /* UDP is nearly always wildcards out the wazoo, it makes no sense to try
281 * harder than this. -DaveM
282 */
283 static struct sock *__udp4_lib_lookup(struct net *net, __be32 saddr,
284 __be16 sport, __be32 daddr, __be16 dport,
285 int dif, struct udp_table *udptable)
286 {
287 struct sock *sk, *result;
288 struct hlist_nulls_node *node;
289 unsigned short hnum = ntohs(dport);
290 unsigned int hash = udp_hashfn(net, hnum, udptable->mask);
291 struct udp_hslot *hslot = &udptable->hash[hash];
292 int score, badness;
293
294 rcu_read_lock();
295 begin:
296 result = NULL;
297 badness = -1;
298 sk_nulls_for_each_rcu(sk, node, &hslot->head) {
299 score = compute_score(sk, net, saddr, hnum, sport,
300 daddr, dport, dif);
301 if (score > badness) {
302 result = sk;
303 badness = score;
304 }
305 }
306 /*
307 * if the nulls value we got at the end of this lookup is
308 * not the expected one, we must restart lookup.
309 * We probably met an item that was moved to another chain.
310 */
311 if (get_nulls_value(node) != hash)
312 goto begin;
313
314 if (result) {
315 if (unlikely(!atomic_inc_not_zero(&result->sk_refcnt)))
316 result = NULL;
317 else if (unlikely(compute_score(result, net, saddr, hnum, sport,
318 daddr, dport, dif) < badness)) {
319 sock_put(result);
320 goto begin;
321 }
322 }
323 rcu_read_unlock();
324 return result;
325 }
326
327 static inline struct sock *__udp4_lib_lookup_skb(struct sk_buff *skb,
328 __be16 sport, __be16 dport,
329 struct udp_table *udptable)
330 {
331 struct sock *sk;
332 const struct iphdr *iph = ip_hdr(skb);
333
334 if (unlikely(sk = skb_steal_sock(skb)))
335 return sk;
336 else
337 return __udp4_lib_lookup(dev_net(skb_dst(skb)->dev), iph->saddr, sport,
338 iph->daddr, dport, inet_iif(skb),
339 udptable);
340 }
341
342 struct sock *udp4_lib_lookup(struct net *net, __be32 saddr, __be16 sport,
343 __be32 daddr, __be16 dport, int dif)
344 {
345 return __udp4_lib_lookup(net, saddr, sport, daddr, dport, dif, &udp_table);
346 }
347 EXPORT_SYMBOL_GPL(udp4_lib_lookup);
348
349 static inline struct sock *udp_v4_mcast_next(struct net *net, struct sock *sk,
350 __be16 loc_port, __be32 loc_addr,
351 __be16 rmt_port, __be32 rmt_addr,
352 int dif)
353 {
354 struct hlist_nulls_node *node;
355 struct sock *s = sk;
356 unsigned short hnum = ntohs(loc_port);
357
358 sk_nulls_for_each_from(s, node) {
359 struct inet_sock *inet = inet_sk(s);
360
361 if (!net_eq(sock_net(s), net) ||
362 s->sk_hash != hnum ||
363 (inet->daddr && inet->daddr != rmt_addr) ||
364 (inet->dport != rmt_port && inet->dport) ||
365 (inet->rcv_saddr && inet->rcv_saddr != loc_addr) ||
366 ipv6_only_sock(s) ||
367 (s->sk_bound_dev_if && s->sk_bound_dev_if != dif))
368 continue;
369 if (!ip_mc_sf_allow(s, loc_addr, rmt_addr, dif))
370 continue;
371 goto found;
372 }
373 s = NULL;
374 found:
375 return s;
376 }
377
378 /*
379 * This routine is called by the ICMP module when it gets some
380 * sort of error condition. If err < 0 then the socket should
381 * be closed and the error returned to the user. If err > 0
382 * it's just the icmp type << 8 | icmp code.
383 * Header points to the ip header of the error packet. We move
384 * on past this. Then (as it used to claim before adjustment)
385 * header points to the first 8 bytes of the udp header. We need
386 * to find the appropriate port.
387 */
388
389 void __udp4_lib_err(struct sk_buff *skb, u32 info, struct udp_table *udptable)
390 {
391 struct inet_sock *inet;
392 struct iphdr *iph = (struct iphdr *)skb->data;
393 struct udphdr *uh = (struct udphdr *)(skb->data+(iph->ihl<<2));
394 const int type = icmp_hdr(skb)->type;
395 const int code = icmp_hdr(skb)->code;
396 struct sock *sk;
397 int harderr;
398 int err;
399 struct net *net = dev_net(skb->dev);
400
401 sk = __udp4_lib_lookup(net, iph->daddr, uh->dest,
402 iph->saddr, uh->source, skb->dev->ifindex, udptable);
403 if (sk == NULL) {
404 ICMP_INC_STATS_BH(net, ICMP_MIB_INERRORS);
405 return; /* No socket for error */
406 }
407
408 err = 0;
409 harderr = 0;
410 inet = inet_sk(sk);
411
412 switch (type) {
413 default:
414 case ICMP_TIME_EXCEEDED:
415 err = EHOSTUNREACH;
416 break;
417 case ICMP_SOURCE_QUENCH:
418 goto out;
419 case ICMP_PARAMETERPROB:
420 err = EPROTO;
421 harderr = 1;
422 break;
423 case ICMP_DEST_UNREACH:
424 if (code == ICMP_FRAG_NEEDED) { /* Path MTU discovery */
425 if (inet->pmtudisc != IP_PMTUDISC_DONT) {
426 err = EMSGSIZE;
427 harderr = 1;
428 break;
429 }
430 goto out;
431 }
432 err = EHOSTUNREACH;
433 if (code <= NR_ICMP_UNREACH) {
434 harderr = icmp_err_convert[code].fatal;
435 err = icmp_err_convert[code].errno;
436 }
437 break;
438 }
439
440 /*
441 * RFC1122: OK. Passes ICMP errors back to application, as per
442 * 4.1.3.3.
443 */
444 if (!inet->recverr) {
445 if (!harderr || sk->sk_state != TCP_ESTABLISHED)
446 goto out;
447 } else {
448 ip_icmp_error(sk, skb, err, uh->dest, info, (u8 *)(uh+1));
449 }
450 sk->sk_err = err;
451 sk->sk_error_report(sk);
452 out:
453 sock_put(sk);
454 }
455
456 void udp_err(struct sk_buff *skb, u32 info)
457 {
458 __udp4_lib_err(skb, info, &udp_table);
459 }
460
461 /*
462 * Throw away all pending data and cancel the corking. Socket is locked.
463 */
464 void udp_flush_pending_frames(struct sock *sk)
465 {
466 struct udp_sock *up = udp_sk(sk);
467
468 if (up->pending) {
469 up->len = 0;
470 up->pending = 0;
471 ip_flush_pending_frames(sk);
472 }
473 }
474 EXPORT_SYMBOL(udp_flush_pending_frames);
475
476 /**
477 * udp4_hwcsum_outgoing - handle outgoing HW checksumming
478 * @sk: socket we are sending on
479 * @skb: sk_buff containing the filled-in UDP header
480 * (checksum field must be zeroed out)
481 */
482 static void udp4_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb,
483 __be32 src, __be32 dst, int len)
484 {
485 unsigned int offset;
486 struct udphdr *uh = udp_hdr(skb);
487 __wsum csum = 0;
488
489 if (skb_queue_len(&sk->sk_write_queue) == 1) {
490 /*
491 * Only one fragment on the socket.
492 */
493 skb->csum_start = skb_transport_header(skb) - skb->head;
494 skb->csum_offset = offsetof(struct udphdr, check);
495 uh->check = ~csum_tcpudp_magic(src, dst, len, IPPROTO_UDP, 0);
496 } else {
497 /*
498 * HW-checksum won't work as there are two or more
499 * fragments on the socket so that all csums of sk_buffs
500 * should be together
501 */
502 offset = skb_transport_offset(skb);
503 skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
504
505 skb->ip_summed = CHECKSUM_NONE;
506
507 skb_queue_walk(&sk->sk_write_queue, skb) {
508 csum = csum_add(csum, skb->csum);
509 }
510
511 uh->check = csum_tcpudp_magic(src, dst, len, IPPROTO_UDP, csum);
512 if (uh->check == 0)
513 uh->check = CSUM_MANGLED_0;
514 }
515 }
516
517 /*
518 * Push out all pending data as one UDP datagram. Socket is locked.
519 */
520 static int udp_push_pending_frames(struct sock *sk)
521 {
522 struct udp_sock *up = udp_sk(sk);
523 struct inet_sock *inet = inet_sk(sk);
524 struct flowi *fl = &inet->cork.fl;
525 struct sk_buff *skb;
526 struct udphdr *uh;
527 int err = 0;
528 int is_udplite = IS_UDPLITE(sk);
529 __wsum csum = 0;
530
531 /* Grab the skbuff where UDP header space exists. */
532 if ((skb = skb_peek(&sk->sk_write_queue)) == NULL)
533 goto out;
534
535 /*
536 * Create a UDP header
537 */
538 uh = udp_hdr(skb);
539 uh->source = fl->fl_ip_sport;
540 uh->dest = fl->fl_ip_dport;
541 uh->len = htons(up->len);
542 uh->check = 0;
543
544 if (is_udplite) /* UDP-Lite */
545 csum = udplite_csum_outgoing(sk, skb);
546
547 else if (sk->sk_no_check == UDP_CSUM_NOXMIT) { /* UDP csum disabled */
548
549 skb->ip_summed = CHECKSUM_NONE;
550 goto send;
551
552 } else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */
553
554 udp4_hwcsum_outgoing(sk, skb, fl->fl4_src, fl->fl4_dst, up->len);
555 goto send;
556
557 } else /* `normal' UDP */
558 csum = udp_csum_outgoing(sk, skb);
559
560 /* add protocol-dependent pseudo-header */
561 uh->check = csum_tcpudp_magic(fl->fl4_src, fl->fl4_dst, up->len,
562 sk->sk_protocol, csum);
563 if (uh->check == 0)
564 uh->check = CSUM_MANGLED_0;
565
566 send:
567 err = ip_push_pending_frames(sk);
568 if (err) {
569 if (err == -ENOBUFS && !inet->recverr) {
570 UDP_INC_STATS_USER(sock_net(sk),
571 UDP_MIB_SNDBUFERRORS, is_udplite);
572 err = 0;
573 }
574 } else
575 UDP_INC_STATS_USER(sock_net(sk),
576 UDP_MIB_OUTDATAGRAMS, is_udplite);
577 out:
578 up->len = 0;
579 up->pending = 0;
580 return err;
581 }
582
583 int udp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
584 size_t len)
585 {
586 struct inet_sock *inet = inet_sk(sk);
587 struct udp_sock *up = udp_sk(sk);
588 int ulen = len;
589 struct ipcm_cookie ipc;
590 struct rtable *rt = NULL;
591 int free = 0;
592 int connected = 0;
593 __be32 daddr, faddr, saddr;
594 __be16 dport;
595 u8 tos;
596 int err, is_udplite = IS_UDPLITE(sk);
597 int corkreq = up->corkflag || msg->msg_flags&MSG_MORE;
598 int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
599
600 if (len > 0xFFFF)
601 return -EMSGSIZE;
602
603 /*
604 * Check the flags.
605 */
606
607 if (msg->msg_flags & MSG_OOB) /* Mirror BSD error message compatibility */
608 return -EOPNOTSUPP;
609
610 ipc.opt = NULL;
611 ipc.shtx.flags = 0;
612
613 if (up->pending) {
614 /*
615 * There are pending frames.
616 * The socket lock must be held while it's corked.
617 */
618 lock_sock(sk);
619 if (likely(up->pending)) {
620 if (unlikely(up->pending != AF_INET)) {
621 release_sock(sk);
622 return -EINVAL;
623 }
624 goto do_append_data;
625 }
626 release_sock(sk);
627 }
628 ulen += sizeof(struct udphdr);
629
630 /*
631 * Get and verify the address.
632 */
633 if (msg->msg_name) {
634 struct sockaddr_in * usin = (struct sockaddr_in *)msg->msg_name;
635 if (msg->msg_namelen < sizeof(*usin))
636 return -EINVAL;
637 if (usin->sin_family != AF_INET) {
638 if (usin->sin_family != AF_UNSPEC)
639 return -EAFNOSUPPORT;
640 }
641
642 daddr = usin->sin_addr.s_addr;
643 dport = usin->sin_port;
644 if (dport == 0)
645 return -EINVAL;
646 } else {
647 if (sk->sk_state != TCP_ESTABLISHED)
648 return -EDESTADDRREQ;
649 daddr = inet->daddr;
650 dport = inet->dport;
651 /* Open fast path for connected socket.
652 Route will not be used, if at least one option is set.
653 */
654 connected = 1;
655 }
656 ipc.addr = inet->saddr;
657
658 ipc.oif = sk->sk_bound_dev_if;
659 err = sock_tx_timestamp(msg, sk, &ipc.shtx);
660 if (err)
661 return err;
662 if (msg->msg_controllen) {
663 err = ip_cmsg_send(sock_net(sk), msg, &ipc);
664 if (err)
665 return err;
666 if (ipc.opt)
667 free = 1;
668 connected = 0;
669 }
670 if (!ipc.opt)
671 ipc.opt = inet->opt;
672
673 saddr = ipc.addr;
674 ipc.addr = faddr = daddr;
675
676 if (ipc.opt && ipc.opt->srr) {
677 if (!daddr)
678 return -EINVAL;
679 faddr = ipc.opt->faddr;
680 connected = 0;
681 }
682 tos = RT_TOS(inet->tos);
683 if (sock_flag(sk, SOCK_LOCALROUTE) ||
684 (msg->msg_flags & MSG_DONTROUTE) ||
685 (ipc.opt && ipc.opt->is_strictroute)) {
686 tos |= RTO_ONLINK;
687 connected = 0;
688 }
689
690 if (ipv4_is_multicast(daddr)) {
691 if (!ipc.oif)
692 ipc.oif = inet->mc_index;
693 if (!saddr)
694 saddr = inet->mc_addr;
695 connected = 0;
696 }
697
698 if (connected)
699 rt = (struct rtable *)sk_dst_check(sk, 0);
700
701 if (rt == NULL) {
702 struct flowi fl = { .oif = ipc.oif,
703 .mark = sk->sk_mark,
704 .nl_u = { .ip4_u =
705 { .daddr = faddr,
706 .saddr = saddr,
707 .tos = tos } },
708 .proto = sk->sk_protocol,
709 .flags = inet_sk_flowi_flags(sk),
710 .uli_u = { .ports =
711 { .sport = inet->sport,
712 .dport = dport } } };
713 struct net *net = sock_net(sk);
714
715 security_sk_classify_flow(sk, &fl);
716 err = ip_route_output_flow(net, &rt, &fl, sk, 1);
717 if (err) {
718 if (err == -ENETUNREACH)
719 IP_INC_STATS_BH(net, IPSTATS_MIB_OUTNOROUTES);
720 goto out;
721 }
722
723 err = -EACCES;
724 if ((rt->rt_flags & RTCF_BROADCAST) &&
725 !sock_flag(sk, SOCK_BROADCAST))
726 goto out;
727 if (connected)
728 sk_dst_set(sk, dst_clone(&rt->u.dst));
729 }
730
731 if (msg->msg_flags&MSG_CONFIRM)
732 goto do_confirm;
733 back_from_confirm:
734
735 saddr = rt->rt_src;
736 if (!ipc.addr)
737 daddr = ipc.addr = rt->rt_dst;
738
739 lock_sock(sk);
740 if (unlikely(up->pending)) {
741 /* The socket is already corked while preparing it. */
742 /* ... which is an evident application bug. --ANK */
743 release_sock(sk);
744
745 LIMIT_NETDEBUG(KERN_DEBUG "udp cork app bug 2\n");
746 err = -EINVAL;
747 goto out;
748 }
749 /*
750 * Now cork the socket to pend data.
751 */
752 inet->cork.fl.fl4_dst = daddr;
753 inet->cork.fl.fl_ip_dport = dport;
754 inet->cork.fl.fl4_src = saddr;
755 inet->cork.fl.fl_ip_sport = inet->sport;
756 up->pending = AF_INET;
757
758 do_append_data:
759 up->len += ulen;
760 getfrag = is_udplite ? udplite_getfrag : ip_generic_getfrag;
761 err = ip_append_data(sk, getfrag, msg->msg_iov, ulen,
762 sizeof(struct udphdr), &ipc, &rt,
763 corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags);
764 if (err)
765 udp_flush_pending_frames(sk);
766 else if (!corkreq)
767 err = udp_push_pending_frames(sk);
768 else if (unlikely(skb_queue_empty(&sk->sk_write_queue)))
769 up->pending = 0;
770 release_sock(sk);
771
772 out:
773 ip_rt_put(rt);
774 if (free)
775 kfree(ipc.opt);
776 if (!err)
777 return len;
778 /*
779 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space. Reporting
780 * ENOBUFS might not be good (it's not tunable per se), but otherwise
781 * we don't have a good statistic (IpOutDiscards but it can be too many
782 * things). We could add another new stat but at least for now that
783 * seems like overkill.
784 */
785 if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
786 UDP_INC_STATS_USER(sock_net(sk),
787 UDP_MIB_SNDBUFERRORS, is_udplite);
788 }
789 return err;
790
791 do_confirm:
792 dst_confirm(&rt->u.dst);
793 if (!(msg->msg_flags&MSG_PROBE) || len)
794 goto back_from_confirm;
795 err = 0;
796 goto out;
797 }
798 EXPORT_SYMBOL(udp_sendmsg);
799
800 int udp_sendpage(struct sock *sk, struct page *page, int offset,
801 size_t size, int flags)
802 {
803 struct udp_sock *up = udp_sk(sk);
804 int ret;
805
806 if (!up->pending) {
807 struct msghdr msg = { .msg_flags = flags|MSG_MORE };
808
809 /* Call udp_sendmsg to specify destination address which
810 * sendpage interface can't pass.
811 * This will succeed only when the socket is connected.
812 */
813 ret = udp_sendmsg(NULL, sk, &msg, 0);
814 if (ret < 0)
815 return ret;
816 }
817
818 lock_sock(sk);
819
820 if (unlikely(!up->pending)) {
821 release_sock(sk);
822
823 LIMIT_NETDEBUG(KERN_DEBUG "udp cork app bug 3\n");
824 return -EINVAL;
825 }
826
827 ret = ip_append_page(sk, page, offset, size, flags);
828 if (ret == -EOPNOTSUPP) {
829 release_sock(sk);
830 return sock_no_sendpage(sk->sk_socket, page, offset,
831 size, flags);
832 }
833 if (ret < 0) {
834 udp_flush_pending_frames(sk);
835 goto out;
836 }
837
838 up->len += size;
839 if (!(up->corkflag || (flags&MSG_MORE)))
840 ret = udp_push_pending_frames(sk);
841 if (!ret)
842 ret = size;
843 out:
844 release_sock(sk);
845 return ret;
846 }
847
848 /*
849 * IOCTL requests applicable to the UDP protocol
850 */
851
852 int udp_ioctl(struct sock *sk, int cmd, unsigned long arg)
853 {
854 switch (cmd) {
855 case SIOCOUTQ:
856 {
857 int amount = sk_wmem_alloc_get(sk);
858
859 return put_user(amount, (int __user *)arg);
860 }
861
862 case SIOCINQ:
863 {
864 struct sk_buff *skb;
865 unsigned long amount;
866
867 amount = 0;
868 spin_lock_bh(&sk->sk_receive_queue.lock);
869 skb = skb_peek(&sk->sk_receive_queue);
870 if (skb != NULL) {
871 /*
872 * We will only return the amount
873 * of this packet since that is all
874 * that will be read.
875 */
876 amount = skb->len - sizeof(struct udphdr);
877 }
878 spin_unlock_bh(&sk->sk_receive_queue.lock);
879 return put_user(amount, (int __user *)arg);
880 }
881
882 default:
883 return -ENOIOCTLCMD;
884 }
885
886 return 0;
887 }
888 EXPORT_SYMBOL(udp_ioctl);
889
890 /*
891 * This should be easy, if there is something there we
892 * return it, otherwise we block.
893 */
894
895 int udp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
896 size_t len, int noblock, int flags, int *addr_len)
897 {
898 struct inet_sock *inet = inet_sk(sk);
899 struct sockaddr_in *sin = (struct sockaddr_in *)msg->msg_name;
900 struct sk_buff *skb;
901 unsigned int ulen, copied;
902 int peeked;
903 int err;
904 int is_udplite = IS_UDPLITE(sk);
905
906 /*
907 * Check any passed addresses
908 */
909 if (addr_len)
910 *addr_len = sizeof(*sin);
911
912 if (flags & MSG_ERRQUEUE)
913 return ip_recv_error(sk, msg, len);
914
915 try_again:
916 skb = __skb_recv_datagram(sk, flags | (noblock ? MSG_DONTWAIT : 0),
917 &peeked, &err);
918 if (!skb)
919 goto out;
920
921 ulen = skb->len - sizeof(struct udphdr);
922 copied = len;
923 if (copied > ulen)
924 copied = ulen;
925 else if (copied < ulen)
926 msg->msg_flags |= MSG_TRUNC;
927
928 /*
929 * If checksum is needed at all, try to do it while copying the
930 * data. If the data is truncated, or if we only want a partial
931 * coverage checksum (UDP-Lite), do it before the copy.
932 */
933
934 if (copied < ulen || UDP_SKB_CB(skb)->partial_cov) {
935 if (udp_lib_checksum_complete(skb))
936 goto csum_copy_err;
937 }
938
939 if (skb_csum_unnecessary(skb))
940 err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr),
941 msg->msg_iov, copied);
942 else {
943 err = skb_copy_and_csum_datagram_iovec(skb,
944 sizeof(struct udphdr),
945 msg->msg_iov);
946
947 if (err == -EINVAL)
948 goto csum_copy_err;
949 }
950
951 if (err)
952 goto out_free;
953
954 if (!peeked)
955 UDP_INC_STATS_USER(sock_net(sk),
956 UDP_MIB_INDATAGRAMS, is_udplite);
957
958 sock_recv_timestamp(msg, sk, skb);
959
960 /* Copy the address. */
961 if (sin) {
962 sin->sin_family = AF_INET;
963 sin->sin_port = udp_hdr(skb)->source;
964 sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
965 memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
966 }
967 if (inet->cmsg_flags)
968 ip_cmsg_recv(msg, skb);
969
970 err = copied;
971 if (flags & MSG_TRUNC)
972 err = ulen;
973
974 out_free:
975 lock_sock(sk);
976 skb_free_datagram(sk, skb);
977 release_sock(sk);
978 out:
979 return err;
980
981 csum_copy_err:
982 lock_sock(sk);
983 if (!skb_kill_datagram(sk, skb, flags))
984 UDP_INC_STATS_USER(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
985 release_sock(sk);
986
987 if (noblock)
988 return -EAGAIN;
989 goto try_again;
990 }
991
992
993 int udp_disconnect(struct sock *sk, int flags)
994 {
995 struct inet_sock *inet = inet_sk(sk);
996 /*
997 * 1003.1g - break association.
998 */
999
1000 sk->sk_state = TCP_CLOSE;
1001 inet->daddr = 0;
1002 inet->dport = 0;
1003 sk->sk_bound_dev_if = 0;
1004 if (!(sk->sk_userlocks & SOCK_BINDADDR_LOCK))
1005 inet_reset_saddr(sk);
1006
1007 if (!(sk->sk_userlocks & SOCK_BINDPORT_LOCK)) {
1008 sk->sk_prot->unhash(sk);
1009 inet->sport = 0;
1010 }
1011 sk_dst_reset(sk);
1012 return 0;
1013 }
1014 EXPORT_SYMBOL(udp_disconnect);
1015
1016 void udp_lib_unhash(struct sock *sk)
1017 {
1018 if (sk_hashed(sk)) {
1019 struct udp_table *udptable = sk->sk_prot->h.udp_table;
1020 struct udp_hslot *hslot = udp_hashslot(udptable, sock_net(sk),
1021 sk->sk_hash);
1022
1023 spin_lock_bh(&hslot->lock);
1024 if (sk_nulls_del_node_init_rcu(sk)) {
1025 inet_sk(sk)->num = 0;
1026 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
1027 }
1028 spin_unlock_bh(&hslot->lock);
1029 }
1030 }
1031 EXPORT_SYMBOL(udp_lib_unhash);
1032
1033 static int __udp_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
1034 {
1035 int is_udplite = IS_UDPLITE(sk);
1036 int rc;
1037
1038 if ((rc = sock_queue_rcv_skb(sk, skb)) < 0) {
1039 /* Note that an ENOMEM error is charged twice */
1040 if (rc == -ENOMEM) {
1041 UDP_INC_STATS_BH(sock_net(sk), UDP_MIB_RCVBUFERRORS,
1042 is_udplite);
1043 atomic_inc(&sk->sk_drops);
1044 }
1045 goto drop;
1046 }
1047
1048 return 0;
1049
1050 drop:
1051 UDP_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
1052 kfree_skb(skb);
1053 return -1;
1054 }
1055
1056 /* returns:
1057 * -1: error
1058 * 0: success
1059 * >0: "udp encap" protocol resubmission
1060 *
1061 * Note that in the success and error cases, the skb is assumed to
1062 * have either been requeued or freed.
1063 */
1064 int udp_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
1065 {
1066 struct udp_sock *up = udp_sk(sk);
1067 int rc;
1068 int is_udplite = IS_UDPLITE(sk);
1069
1070 /*
1071 * Charge it to the socket, dropping if the queue is full.
1072 */
1073 if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb))
1074 goto drop;
1075 nf_reset(skb);
1076
1077 if (up->encap_type) {
1078 /*
1079 * This is an encapsulation socket so pass the skb to
1080 * the socket's udp_encap_rcv() hook. Otherwise, just
1081 * fall through and pass this up the UDP socket.
1082 * up->encap_rcv() returns the following value:
1083 * =0 if skb was successfully passed to the encap
1084 * handler or was discarded by it.
1085 * >0 if skb should be passed on to UDP.
1086 * <0 if skb should be resubmitted as proto -N
1087 */
1088
1089 /* if we're overly short, let UDP handle it */
1090 if (skb->len > sizeof(struct udphdr) &&
1091 up->encap_rcv != NULL) {
1092 int ret;
1093
1094 ret = (*up->encap_rcv)(sk, skb);
1095 if (ret <= 0) {
1096 UDP_INC_STATS_BH(sock_net(sk),
1097 UDP_MIB_INDATAGRAMS,
1098 is_udplite);
1099 return -ret;
1100 }
1101 }
1102
1103 /* FALLTHROUGH -- it's a UDP Packet */
1104 }
1105
1106 /*
1107 * UDP-Lite specific tests, ignored on UDP sockets
1108 */
1109 if ((is_udplite & UDPLITE_RECV_CC) && UDP_SKB_CB(skb)->partial_cov) {
1110
1111 /*
1112 * MIB statistics other than incrementing the error count are
1113 * disabled for the following two types of errors: these depend
1114 * on the application settings, not on the functioning of the
1115 * protocol stack as such.
1116 *
1117 * RFC 3828 here recommends (sec 3.3): "There should also be a
1118 * way ... to ... at least let the receiving application block
1119 * delivery of packets with coverage values less than a value
1120 * provided by the application."
1121 */
1122 if (up->pcrlen == 0) { /* full coverage was set */
1123 LIMIT_NETDEBUG(KERN_WARNING "UDPLITE: partial coverage "
1124 "%d while full coverage %d requested\n",
1125 UDP_SKB_CB(skb)->cscov, skb->len);
1126 goto drop;
1127 }
1128 /* The next case involves violating the min. coverage requested
1129 * by the receiver. This is subtle: if receiver wants x and x is
1130 * greater than the buffersize/MTU then receiver will complain
1131 * that it wants x while sender emits packets of smaller size y.
1132 * Therefore the above ...()->partial_cov statement is essential.
1133 */
1134 if (UDP_SKB_CB(skb)->cscov < up->pcrlen) {
1135 LIMIT_NETDEBUG(KERN_WARNING
1136 "UDPLITE: coverage %d too small, need min %d\n",
1137 UDP_SKB_CB(skb)->cscov, up->pcrlen);
1138 goto drop;
1139 }
1140 }
1141
1142 if (sk->sk_filter) {
1143 if (udp_lib_checksum_complete(skb))
1144 goto drop;
1145 }
1146
1147 rc = 0;
1148
1149 bh_lock_sock(sk);
1150 if (!sock_owned_by_user(sk))
1151 rc = __udp_queue_rcv_skb(sk, skb);
1152 else
1153 sk_add_backlog(sk, skb);
1154 bh_unlock_sock(sk);
1155
1156 return rc;
1157
1158 drop:
1159 UDP_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
1160 kfree_skb(skb);
1161 return -1;
1162 }
1163
1164 /*
1165 * Multicasts and broadcasts go to each listener.
1166 *
1167 * Note: called only from the BH handler context,
1168 * so we don't need to lock the hashes.
1169 */
1170 static int __udp4_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
1171 struct udphdr *uh,
1172 __be32 saddr, __be32 daddr,
1173 struct udp_table *udptable)
1174 {
1175 struct sock *sk;
1176 struct udp_hslot *hslot = udp_hashslot(udptable, net, ntohs(uh->dest));
1177 int dif;
1178
1179 spin_lock(&hslot->lock);
1180 sk = sk_nulls_head(&hslot->head);
1181 dif = skb->dev->ifindex;
1182 sk = udp_v4_mcast_next(net, sk, uh->dest, daddr, uh->source, saddr, dif);
1183 if (sk) {
1184 struct sock *sknext = NULL;
1185
1186 do {
1187 struct sk_buff *skb1 = skb;
1188
1189 sknext = udp_v4_mcast_next(net, sk_nulls_next(sk), uh->dest,
1190 daddr, uh->source, saddr,
1191 dif);
1192 if (sknext)
1193 skb1 = skb_clone(skb, GFP_ATOMIC);
1194
1195 if (skb1) {
1196 int ret = udp_queue_rcv_skb(sk, skb1);
1197 if (ret > 0)
1198 /* we should probably re-process instead
1199 * of dropping packets here. */
1200 kfree_skb(skb1);
1201 }
1202 sk = sknext;
1203 } while (sknext);
1204 } else
1205 consume_skb(skb);
1206 spin_unlock(&hslot->lock);
1207 return 0;
1208 }
1209
1210 /* Initialize UDP checksum. If exited with zero value (success),
1211 * CHECKSUM_UNNECESSARY means, that no more checks are required.
1212 * Otherwise, csum completion requires chacksumming packet body,
1213 * including udp header and folding it to skb->csum.
1214 */
1215 static inline int udp4_csum_init(struct sk_buff *skb, struct udphdr *uh,
1216 int proto)
1217 {
1218 const struct iphdr *iph;
1219 int err;
1220
1221 UDP_SKB_CB(skb)->partial_cov = 0;
1222 UDP_SKB_CB(skb)->cscov = skb->len;
1223
1224 if (proto == IPPROTO_UDPLITE) {
1225 err = udplite_checksum_init(skb, uh);
1226 if (err)
1227 return err;
1228 }
1229
1230 iph = ip_hdr(skb);
1231 if (uh->check == 0) {
1232 skb->ip_summed = CHECKSUM_UNNECESSARY;
1233 } else if (skb->ip_summed == CHECKSUM_COMPLETE) {
1234 if (!csum_tcpudp_magic(iph->saddr, iph->daddr, skb->len,
1235 proto, skb->csum))
1236 skb->ip_summed = CHECKSUM_UNNECESSARY;
1237 }
1238 if (!skb_csum_unnecessary(skb))
1239 skb->csum = csum_tcpudp_nofold(iph->saddr, iph->daddr,
1240 skb->len, proto, 0);
1241 /* Probably, we should checksum udp header (it should be in cache
1242 * in any case) and data in tiny packets (< rx copybreak).
1243 */
1244
1245 return 0;
1246 }
1247
1248 /*
1249 * All we need to do is get the socket, and then do a checksum.
1250 */
1251
1252 int __udp4_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
1253 int proto)
1254 {
1255 struct sock *sk;
1256 struct udphdr *uh;
1257 unsigned short ulen;
1258 struct rtable *rt = skb_rtable(skb);
1259 __be32 saddr, daddr;
1260 struct net *net = dev_net(skb->dev);
1261
1262 /*
1263 * Validate the packet.
1264 */
1265 if (!pskb_may_pull(skb, sizeof(struct udphdr)))
1266 goto drop; /* No space for header. */
1267
1268 uh = udp_hdr(skb);
1269 ulen = ntohs(uh->len);
1270 if (ulen > skb->len)
1271 goto short_packet;
1272
1273 if (proto == IPPROTO_UDP) {
1274 /* UDP validates ulen. */
1275 if (ulen < sizeof(*uh) || pskb_trim_rcsum(skb, ulen))
1276 goto short_packet;
1277 uh = udp_hdr(skb);
1278 }
1279
1280 if (udp4_csum_init(skb, uh, proto))
1281 goto csum_error;
1282
1283 saddr = ip_hdr(skb)->saddr;
1284 daddr = ip_hdr(skb)->daddr;
1285
1286 if (rt->rt_flags & (RTCF_BROADCAST|RTCF_MULTICAST))
1287 return __udp4_lib_mcast_deliver(net, skb, uh,
1288 saddr, daddr, udptable);
1289
1290 sk = __udp4_lib_lookup_skb(skb, uh->source, uh->dest, udptable);
1291
1292 if (sk != NULL) {
1293 int ret = udp_queue_rcv_skb(sk, skb);
1294 sock_put(sk);
1295
1296 /* a return value > 0 means to resubmit the input, but
1297 * it wants the return to be -protocol, or 0
1298 */
1299 if (ret > 0)
1300 return -ret;
1301 return 0;
1302 }
1303
1304 if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb))
1305 goto drop;
1306 nf_reset(skb);
1307
1308 /* No socket. Drop packet silently, if checksum is wrong */
1309 if (udp_lib_checksum_complete(skb))
1310 goto csum_error;
1311
1312 UDP_INC_STATS_BH(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE);
1313 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
1314
1315 /*
1316 * Hmm. We got an UDP packet to a port to which we
1317 * don't wanna listen. Ignore it.
1318 */
1319 kfree_skb(skb);
1320 return 0;
1321
1322 short_packet:
1323 LIMIT_NETDEBUG(KERN_DEBUG "UDP%s: short packet: From %pI4:%u %d/%d to %pI4:%u\n",
1324 proto == IPPROTO_UDPLITE ? "-Lite" : "",
1325 &saddr,
1326 ntohs(uh->source),
1327 ulen,
1328 skb->len,
1329 &daddr,
1330 ntohs(uh->dest));
1331 goto drop;
1332
1333 csum_error:
1334 /*
1335 * RFC1122: OK. Discards the bad packet silently (as far as
1336 * the network is concerned, anyway) as per 4.1.3.4 (MUST).
1337 */
1338 LIMIT_NETDEBUG(KERN_DEBUG "UDP%s: bad checksum. From %pI4:%u to %pI4:%u ulen %d\n",
1339 proto == IPPROTO_UDPLITE ? "-Lite" : "",
1340 &saddr,
1341 ntohs(uh->source),
1342 &daddr,
1343 ntohs(uh->dest),
1344 ulen);
1345 drop:
1346 UDP_INC_STATS_BH(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE);
1347 kfree_skb(skb);
1348 return 0;
1349 }
1350
1351 int udp_rcv(struct sk_buff *skb)
1352 {
1353 return __udp4_lib_rcv(skb, &udp_table, IPPROTO_UDP);
1354 }
1355
1356 void udp_destroy_sock(struct sock *sk)
1357 {
1358 lock_sock(sk);
1359 udp_flush_pending_frames(sk);
1360 release_sock(sk);
1361 }
1362
1363 /*
1364 * Socket option code for UDP
1365 */
1366 int udp_lib_setsockopt(struct sock *sk, int level, int optname,
1367 char __user *optval, unsigned int optlen,
1368 int (*push_pending_frames)(struct sock *))
1369 {
1370 struct udp_sock *up = udp_sk(sk);
1371 int val;
1372 int err = 0;
1373 int is_udplite = IS_UDPLITE(sk);
1374
1375 if (optlen < sizeof(int))
1376 return -EINVAL;
1377
1378 if (get_user(val, (int __user *)optval))
1379 return -EFAULT;
1380
1381 switch (optname) {
1382 case UDP_CORK:
1383 if (val != 0) {
1384 up->corkflag = 1;
1385 } else {
1386 up->corkflag = 0;
1387 lock_sock(sk);
1388 (*push_pending_frames)(sk);
1389 release_sock(sk);
1390 }
1391 break;
1392
1393 case UDP_ENCAP:
1394 switch (val) {
1395 case 0:
1396 case UDP_ENCAP_ESPINUDP:
1397 case UDP_ENCAP_ESPINUDP_NON_IKE:
1398 up->encap_rcv = xfrm4_udp_encap_rcv;
1399 /* FALLTHROUGH */
1400 case UDP_ENCAP_L2TPINUDP:
1401 up->encap_type = val;
1402 break;
1403 default:
1404 err = -ENOPROTOOPT;
1405 break;
1406 }
1407 break;
1408
1409 /*
1410 * UDP-Lite's partial checksum coverage (RFC 3828).
1411 */
1412 /* The sender sets actual checksum coverage length via this option.
1413 * The case coverage > packet length is handled by send module. */
1414 case UDPLITE_SEND_CSCOV:
1415 if (!is_udplite) /* Disable the option on UDP sockets */
1416 return -ENOPROTOOPT;
1417 if (val != 0 && val < 8) /* Illegal coverage: use default (8) */
1418 val = 8;
1419 else if (val > USHORT_MAX)
1420 val = USHORT_MAX;
1421 up->pcslen = val;
1422 up->pcflag |= UDPLITE_SEND_CC;
1423 break;
1424
1425 /* The receiver specifies a minimum checksum coverage value. To make
1426 * sense, this should be set to at least 8 (as done below). If zero is
1427 * used, this again means full checksum coverage. */
1428 case UDPLITE_RECV_CSCOV:
1429 if (!is_udplite) /* Disable the option on UDP sockets */
1430 return -ENOPROTOOPT;
1431 if (val != 0 && val < 8) /* Avoid silly minimal values. */
1432 val = 8;
1433 else if (val > USHORT_MAX)
1434 val = USHORT_MAX;
1435 up->pcrlen = val;
1436 up->pcflag |= UDPLITE_RECV_CC;
1437 break;
1438
1439 default:
1440 err = -ENOPROTOOPT;
1441 break;
1442 }
1443
1444 return err;
1445 }
1446 EXPORT_SYMBOL(udp_lib_setsockopt);
1447
1448 int udp_setsockopt(struct sock *sk, int level, int optname,
1449 char __user *optval, unsigned int optlen)
1450 {
1451 if (level == SOL_UDP || level == SOL_UDPLITE)
1452 return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1453 udp_push_pending_frames);
1454 return ip_setsockopt(sk, level, optname, optval, optlen);
1455 }
1456
1457 #ifdef CONFIG_COMPAT
1458 int compat_udp_setsockopt(struct sock *sk, int level, int optname,
1459 char __user *optval, unsigned int optlen)
1460 {
1461 if (level == SOL_UDP || level == SOL_UDPLITE)
1462 return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1463 udp_push_pending_frames);
1464 return compat_ip_setsockopt(sk, level, optname, optval, optlen);
1465 }
1466 #endif
1467
1468 int udp_lib_getsockopt(struct sock *sk, int level, int optname,
1469 char __user *optval, int __user *optlen)
1470 {
1471 struct udp_sock *up = udp_sk(sk);
1472 int val, len;
1473
1474 if (get_user(len, optlen))
1475 return -EFAULT;
1476
1477 len = min_t(unsigned int, len, sizeof(int));
1478
1479 if (len < 0)
1480 return -EINVAL;
1481
1482 switch (optname) {
1483 case UDP_CORK:
1484 val = up->corkflag;
1485 break;
1486
1487 case UDP_ENCAP:
1488 val = up->encap_type;
1489 break;
1490
1491 /* The following two cannot be changed on UDP sockets, the return is
1492 * always 0 (which corresponds to the full checksum coverage of UDP). */
1493 case UDPLITE_SEND_CSCOV:
1494 val = up->pcslen;
1495 break;
1496
1497 case UDPLITE_RECV_CSCOV:
1498 val = up->pcrlen;
1499 break;
1500
1501 default:
1502 return -ENOPROTOOPT;
1503 }
1504
1505 if (put_user(len, optlen))
1506 return -EFAULT;
1507 if (copy_to_user(optval, &val, len))
1508 return -EFAULT;
1509 return 0;
1510 }
1511 EXPORT_SYMBOL(udp_lib_getsockopt);
1512
1513 int udp_getsockopt(struct sock *sk, int level, int optname,
1514 char __user *optval, int __user *optlen)
1515 {
1516 if (level == SOL_UDP || level == SOL_UDPLITE)
1517 return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1518 return ip_getsockopt(sk, level, optname, optval, optlen);
1519 }
1520
1521 #ifdef CONFIG_COMPAT
1522 int compat_udp_getsockopt(struct sock *sk, int level, int optname,
1523 char __user *optval, int __user *optlen)
1524 {
1525 if (level == SOL_UDP || level == SOL_UDPLITE)
1526 return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1527 return compat_ip_getsockopt(sk, level, optname, optval, optlen);
1528 }
1529 #endif
1530 /**
1531 * udp_poll - wait for a UDP event.
1532 * @file - file struct
1533 * @sock - socket
1534 * @wait - poll table
1535 *
1536 * This is same as datagram poll, except for the special case of
1537 * blocking sockets. If application is using a blocking fd
1538 * and a packet with checksum error is in the queue;
1539 * then it could get return from select indicating data available
1540 * but then block when reading it. Add special case code
1541 * to work around these arguably broken applications.
1542 */
1543 unsigned int udp_poll(struct file *file, struct socket *sock, poll_table *wait)
1544 {
1545 unsigned int mask = datagram_poll(file, sock, wait);
1546 struct sock *sk = sock->sk;
1547 int is_lite = IS_UDPLITE(sk);
1548
1549 /* Check for false positives due to checksum errors */
1550 if ((mask & POLLRDNORM) &&
1551 !(file->f_flags & O_NONBLOCK) &&
1552 !(sk->sk_shutdown & RCV_SHUTDOWN)) {
1553 struct sk_buff_head *rcvq = &sk->sk_receive_queue;
1554 struct sk_buff *skb;
1555
1556 spin_lock_bh(&rcvq->lock);
1557 while ((skb = skb_peek(rcvq)) != NULL &&
1558 udp_lib_checksum_complete(skb)) {
1559 UDP_INC_STATS_BH(sock_net(sk),
1560 UDP_MIB_INERRORS, is_lite);
1561 __skb_unlink(skb, rcvq);
1562 kfree_skb(skb);
1563 }
1564 spin_unlock_bh(&rcvq->lock);
1565
1566 /* nothing to see, move along */
1567 if (skb == NULL)
1568 mask &= ~(POLLIN | POLLRDNORM);
1569 }
1570
1571 return mask;
1572
1573 }
1574 EXPORT_SYMBOL(udp_poll);
1575
1576 struct proto udp_prot = {
1577 .name = "UDP",
1578 .owner = THIS_MODULE,
1579 .close = udp_lib_close,
1580 .connect = ip4_datagram_connect,
1581 .disconnect = udp_disconnect,
1582 .ioctl = udp_ioctl,
1583 .destroy = udp_destroy_sock,
1584 .setsockopt = udp_setsockopt,
1585 .getsockopt = udp_getsockopt,
1586 .sendmsg = udp_sendmsg,
1587 .recvmsg = udp_recvmsg,
1588 .sendpage = udp_sendpage,
1589 .backlog_rcv = __udp_queue_rcv_skb,
1590 .hash = udp_lib_hash,
1591 .unhash = udp_lib_unhash,
1592 .get_port = udp_v4_get_port,
1593 .memory_allocated = &udp_memory_allocated,
1594 .sysctl_mem = sysctl_udp_mem,
1595 .sysctl_wmem = &sysctl_udp_wmem_min,
1596 .sysctl_rmem = &sysctl_udp_rmem_min,
1597 .obj_size = sizeof(struct udp_sock),
1598 .slab_flags = SLAB_DESTROY_BY_RCU,
1599 .h.udp_table = &udp_table,
1600 #ifdef CONFIG_COMPAT
1601 .compat_setsockopt = compat_udp_setsockopt,
1602 .compat_getsockopt = compat_udp_getsockopt,
1603 #endif
1604 };
1605 EXPORT_SYMBOL(udp_prot);
1606
1607 /* ------------------------------------------------------------------------ */
1608 #ifdef CONFIG_PROC_FS
1609
1610 static struct sock *udp_get_first(struct seq_file *seq, int start)
1611 {
1612 struct sock *sk;
1613 struct udp_iter_state *state = seq->private;
1614 struct net *net = seq_file_net(seq);
1615
1616 for (state->bucket = start; state->bucket <= state->udp_table->mask;
1617 ++state->bucket) {
1618 struct hlist_nulls_node *node;
1619 struct udp_hslot *hslot = &state->udp_table->hash[state->bucket];
1620
1621 if (hlist_nulls_empty(&hslot->head))
1622 continue;
1623
1624 spin_lock_bh(&hslot->lock);
1625 sk_nulls_for_each(sk, node, &hslot->head) {
1626 if (!net_eq(sock_net(sk), net))
1627 continue;
1628 if (sk->sk_family == state->family)
1629 goto found;
1630 }
1631 spin_unlock_bh(&hslot->lock);
1632 }
1633 sk = NULL;
1634 found:
1635 return sk;
1636 }
1637
1638 static struct sock *udp_get_next(struct seq_file *seq, struct sock *sk)
1639 {
1640 struct udp_iter_state *state = seq->private;
1641 struct net *net = seq_file_net(seq);
1642
1643 do {
1644 sk = sk_nulls_next(sk);
1645 } while (sk && (!net_eq(sock_net(sk), net) || sk->sk_family != state->family));
1646
1647 if (!sk) {
1648 if (state->bucket <= state->udp_table->mask)
1649 spin_unlock_bh(&state->udp_table->hash[state->bucket].lock);
1650 return udp_get_first(seq, state->bucket + 1);
1651 }
1652 return sk;
1653 }
1654
1655 static struct sock *udp_get_idx(struct seq_file *seq, loff_t pos)
1656 {
1657 struct sock *sk = udp_get_first(seq, 0);
1658
1659 if (sk)
1660 while (pos && (sk = udp_get_next(seq, sk)) != NULL)
1661 --pos;
1662 return pos ? NULL : sk;
1663 }
1664
1665 static void *udp_seq_start(struct seq_file *seq, loff_t *pos)
1666 {
1667 struct udp_iter_state *state = seq->private;
1668 state->bucket = MAX_UDP_PORTS;
1669
1670 return *pos ? udp_get_idx(seq, *pos-1) : SEQ_START_TOKEN;
1671 }
1672
1673 static void *udp_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1674 {
1675 struct sock *sk;
1676
1677 if (v == SEQ_START_TOKEN)
1678 sk = udp_get_idx(seq, 0);
1679 else
1680 sk = udp_get_next(seq, v);
1681
1682 ++*pos;
1683 return sk;
1684 }
1685
1686 static void udp_seq_stop(struct seq_file *seq, void *v)
1687 {
1688 struct udp_iter_state *state = seq->private;
1689
1690 if (state->bucket <= state->udp_table->mask)
1691 spin_unlock_bh(&state->udp_table->hash[state->bucket].lock);
1692 }
1693
1694 static int udp_seq_open(struct inode *inode, struct file *file)
1695 {
1696 struct udp_seq_afinfo *afinfo = PDE(inode)->data;
1697 struct udp_iter_state *s;
1698 int err;
1699
1700 err = seq_open_net(inode, file, &afinfo->seq_ops,
1701 sizeof(struct udp_iter_state));
1702 if (err < 0)
1703 return err;
1704
1705 s = ((struct seq_file *)file->private_data)->private;
1706 s->family = afinfo->family;
1707 s->udp_table = afinfo->udp_table;
1708 return err;
1709 }
1710
1711 /* ------------------------------------------------------------------------ */
1712 int udp_proc_register(struct net *net, struct udp_seq_afinfo *afinfo)
1713 {
1714 struct proc_dir_entry *p;
1715 int rc = 0;
1716
1717 afinfo->seq_fops.open = udp_seq_open;
1718 afinfo->seq_fops.read = seq_read;
1719 afinfo->seq_fops.llseek = seq_lseek;
1720 afinfo->seq_fops.release = seq_release_net;
1721
1722 afinfo->seq_ops.start = udp_seq_start;
1723 afinfo->seq_ops.next = udp_seq_next;
1724 afinfo->seq_ops.stop = udp_seq_stop;
1725
1726 p = proc_create_data(afinfo->name, S_IRUGO, net->proc_net,
1727 &afinfo->seq_fops, afinfo);
1728 if (!p)
1729 rc = -ENOMEM;
1730 return rc;
1731 }
1732 EXPORT_SYMBOL(udp_proc_register);
1733
1734 void udp_proc_unregister(struct net *net, struct udp_seq_afinfo *afinfo)
1735 {
1736 proc_net_remove(net, afinfo->name);
1737 }
1738 EXPORT_SYMBOL(udp_proc_unregister);
1739
1740 /* ------------------------------------------------------------------------ */
1741 static void udp4_format_sock(struct sock *sp, struct seq_file *f,
1742 int bucket, int *len)
1743 {
1744 struct inet_sock *inet = inet_sk(sp);
1745 __be32 dest = inet->daddr;
1746 __be32 src = inet->rcv_saddr;
1747 __u16 destp = ntohs(inet->dport);
1748 __u16 srcp = ntohs(inet->sport);
1749
1750 seq_printf(f, "%5d: %08X:%04X %08X:%04X"
1751 " %02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %p %d%n",
1752 bucket, src, srcp, dest, destp, sp->sk_state,
1753 sk_wmem_alloc_get(sp),
1754 sk_rmem_alloc_get(sp),
1755 0, 0L, 0, sock_i_uid(sp), 0, sock_i_ino(sp),
1756 atomic_read(&sp->sk_refcnt), sp,
1757 atomic_read(&sp->sk_drops), len);
1758 }
1759
1760 int udp4_seq_show(struct seq_file *seq, void *v)
1761 {
1762 if (v == SEQ_START_TOKEN)
1763 seq_printf(seq, "%-127s\n",
1764 " sl local_address rem_address st tx_queue "
1765 "rx_queue tr tm->when retrnsmt uid timeout "
1766 "inode ref pointer drops");
1767 else {
1768 struct udp_iter_state *state = seq->private;
1769 int len;
1770
1771 udp4_format_sock(v, seq, state->bucket, &len);
1772 seq_printf(seq, "%*s\n", 127 - len, "");
1773 }
1774 return 0;
1775 }
1776
1777 /* ------------------------------------------------------------------------ */
1778 static struct udp_seq_afinfo udp4_seq_afinfo = {
1779 .name = "udp",
1780 .family = AF_INET,
1781 .udp_table = &udp_table,
1782 .seq_fops = {
1783 .owner = THIS_MODULE,
1784 },
1785 .seq_ops = {
1786 .show = udp4_seq_show,
1787 },
1788 };
1789
1790 static int udp4_proc_init_net(struct net *net)
1791 {
1792 return udp_proc_register(net, &udp4_seq_afinfo);
1793 }
1794
1795 static void udp4_proc_exit_net(struct net *net)
1796 {
1797 udp_proc_unregister(net, &udp4_seq_afinfo);
1798 }
1799
1800 static struct pernet_operations udp4_net_ops = {
1801 .init = udp4_proc_init_net,
1802 .exit = udp4_proc_exit_net,
1803 };
1804
1805 int __init udp4_proc_init(void)
1806 {
1807 return register_pernet_subsys(&udp4_net_ops);
1808 }
1809
1810 void udp4_proc_exit(void)
1811 {
1812 unregister_pernet_subsys(&udp4_net_ops);
1813 }
1814 #endif /* CONFIG_PROC_FS */
1815
1816 static __initdata unsigned long uhash_entries;
1817 static int __init set_uhash_entries(char *str)
1818 {
1819 if (!str)
1820 return 0;
1821 uhash_entries = simple_strtoul(str, &str, 0);
1822 if (uhash_entries && uhash_entries < UDP_HTABLE_SIZE_MIN)
1823 uhash_entries = UDP_HTABLE_SIZE_MIN;
1824 return 1;
1825 }
1826 __setup("uhash_entries=", set_uhash_entries);
1827
1828 void __init udp_table_init(struct udp_table *table, const char *name)
1829 {
1830 unsigned int i;
1831
1832 if (!CONFIG_BASE_SMALL)
1833 table->hash = alloc_large_system_hash(name,
1834 sizeof(struct udp_hslot),
1835 uhash_entries,
1836 21, /* one slot per 2 MB */
1837 0,
1838 &table->log,
1839 &table->mask,
1840 64 * 1024);
1841 /*
1842 * Make sure hash table has the minimum size
1843 */
1844 if (CONFIG_BASE_SMALL || table->mask < UDP_HTABLE_SIZE_MIN - 1) {
1845 table->hash = kmalloc(UDP_HTABLE_SIZE_MIN *
1846 sizeof(struct udp_hslot), GFP_KERNEL);
1847 if (!table->hash)
1848 panic(name);
1849 table->log = ilog2(UDP_HTABLE_SIZE_MIN);
1850 table->mask = UDP_HTABLE_SIZE_MIN - 1;
1851 }
1852 for (i = 0; i <= table->mask; i++) {
1853 INIT_HLIST_NULLS_HEAD(&table->hash[i].head, i);
1854 spin_lock_init(&table->hash[i].lock);
1855 }
1856 }
1857
1858 void __init udp_init(void)
1859 {
1860 unsigned long nr_pages, limit;
1861
1862 udp_table_init(&udp_table, "UDP");
1863 /* Set the pressure threshold up by the same strategy of TCP. It is a
1864 * fraction of global memory that is up to 1/2 at 256 MB, decreasing
1865 * toward zero with the amount of memory, with a floor of 128 pages.
1866 */
1867 nr_pages = totalram_pages - totalhigh_pages;
1868 limit = min(nr_pages, 1UL<<(28-PAGE_SHIFT)) >> (20-PAGE_SHIFT);
1869 limit = (limit * (nr_pages >> (20-PAGE_SHIFT))) >> (PAGE_SHIFT-11);
1870 limit = max(limit, 128UL);
1871 sysctl_udp_mem[0] = limit / 4 * 3;
1872 sysctl_udp_mem[1] = limit;
1873 sysctl_udp_mem[2] = sysctl_udp_mem[0] * 2;
1874
1875 sysctl_udp_rmem_min = SK_MEM_QUANTUM;
1876 sysctl_udp_wmem_min = SK_MEM_QUANTUM;
1877 }
1878
1879 int udp4_ufo_send_check(struct sk_buff *skb)
1880 {
1881 const struct iphdr *iph;
1882 struct udphdr *uh;
1883
1884 if (!pskb_may_pull(skb, sizeof(*uh)))
1885 return -EINVAL;
1886
1887 iph = ip_hdr(skb);
1888 uh = udp_hdr(skb);
1889
1890 uh->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr, skb->len,
1891 IPPROTO_UDP, 0);
1892 skb->csum_start = skb_transport_header(skb) - skb->head;
1893 skb->csum_offset = offsetof(struct udphdr, check);
1894 skb->ip_summed = CHECKSUM_PARTIAL;
1895 return 0;
1896 }
1897
1898 struct sk_buff *udp4_ufo_fragment(struct sk_buff *skb, int features)
1899 {
1900 struct sk_buff *segs = ERR_PTR(-EINVAL);
1901 unsigned int mss;
1902 int offset;
1903 __wsum csum;
1904
1905 mss = skb_shinfo(skb)->gso_size;
1906 if (unlikely(skb->len <= mss))
1907 goto out;
1908
1909 if (skb_gso_ok(skb, features | NETIF_F_GSO_ROBUST)) {
1910 /* Packet is from an untrusted source, reset gso_segs. */
1911 int type = skb_shinfo(skb)->gso_type;
1912
1913 if (unlikely(type & ~(SKB_GSO_UDP | SKB_GSO_DODGY) ||
1914 !(type & (SKB_GSO_UDP))))
1915 goto out;
1916
1917 skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(skb->len, mss);
1918
1919 segs = NULL;
1920 goto out;
1921 }
1922
1923 /* Do software UFO. Complete and fill in the UDP checksum as HW cannot
1924 * do checksum of UDP packets sent as multiple IP fragments.
1925 */
1926 offset = skb->csum_start - skb_headroom(skb);
1927 csum = skb_checksum(skb, offset, skb->len - offset, 0);
1928 offset += skb->csum_offset;
1929 *(__sum16 *)(skb->data + offset) = csum_fold(csum);
1930 skb->ip_summed = CHECKSUM_NONE;
1931
1932 /* Fragment the skb. IP headers of the fragments are updated in
1933 * inet_gso_segment()
1934 */
1935 segs = skb_segment(skb, features);
1936 out:
1937 return segs;
1938 }
1939
kernel source for telekom puls (alcatel/mediatek)