blob: ec93335901ddc45d09f7c85c53270ea9a6772207 [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 options processing module for ip.c
7 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07008 * Authors: A.N.Kuznetsov
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +09009 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070010 */
11
Randy Dunlap4fc268d2006-01-11 12:17:47 -080012#include <linux/capability.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070013#include <linux/module.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090014#include <linux/slab.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070015#include <linux/types.h>
16#include <asm/uaccess.h>
Chris Metcalf48bdf0722011-05-29 10:55:44 +000017#include <asm/unaligned.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070018#include <linux/skbuff.h>
19#include <linux/ip.h>
20#include <linux/icmp.h>
21#include <linux/netdevice.h>
22#include <linux/rtnetlink.h>
23#include <net/sock.h>
24#include <net/ip.h>
25#include <net/icmp.h>
Arnaldo Carvalho de Melo14c85022005-12-27 02:43:12 -020026#include <net/route.h>
Paul Moore11a03f72006-08-03 16:46:20 -070027#include <net/cipso_ipv4.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070028
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +090029/*
Linus Torvalds1da177e2005-04-16 15:20:36 -070030 * Write options to IP header, record destination address to
31 * source route option, address of outgoing interface
32 * (we should already know it, so that this function is allowed be
33 * called only after routing decision) and timestamp,
34 * if we originate this datagram.
35 *
36 * daddr is real destination address, next hop is recorded in IP header.
37 * saddr is address of outgoing interface.
38 */
39
Eric Dumazetf6d8bd02011-04-21 09:45:37 +000040void ip_options_build(struct sk_buff *skb, struct ip_options *opt,
David S. Miller8e363602011-05-13 17:29:41 -040041 __be32 daddr, struct rtable *rt, int is_frag)
Linus Torvalds1da177e2005-04-16 15:20:36 -070042{
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -070043 unsigned char *iph = skb_network_header(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -070044
45 memcpy(&(IPCB(skb)->opt), opt, sizeof(struct ip_options));
46 memcpy(iph+sizeof(struct iphdr), opt->__data, opt->optlen);
47 opt = &(IPCB(skb)->opt);
Linus Torvalds1da177e2005-04-16 15:20:36 -070048
49 if (opt->srr)
50 memcpy(iph+opt->srr+iph[opt->srr+1]-4, &daddr, 4);
51
52 if (!is_frag) {
53 if (opt->rr_needaddr)
David S. Miller8e363602011-05-13 17:29:41 -040054 ip_rt_get_source(iph+opt->rr+iph[opt->rr+2]-5, skb, rt);
Linus Torvalds1da177e2005-04-16 15:20:36 -070055 if (opt->ts_needaddr)
David S. Miller8e363602011-05-13 17:29:41 -040056 ip_rt_get_source(iph+opt->ts+iph[opt->ts+2]-9, skb, rt);
Linus Torvalds1da177e2005-04-16 15:20:36 -070057 if (opt->ts_needtime) {
YOSHIFUJI Hideakif25c3d62008-04-21 02:34:08 -070058 struct timespec tv;
Al Viroe25d2ca2006-09-27 18:28:47 -070059 __be32 midtime;
YOSHIFUJI Hideakif25c3d62008-04-21 02:34:08 -070060 getnstimeofday(&tv);
61 midtime = htonl((tv.tv_sec % 86400) * MSEC_PER_SEC + tv.tv_nsec / NSEC_PER_MSEC);
Linus Torvalds1da177e2005-04-16 15:20:36 -070062 memcpy(iph+opt->ts+iph[opt->ts+2]-5, &midtime, 4);
63 }
64 return;
65 }
66 if (opt->rr) {
67 memset(iph+opt->rr, IPOPT_NOP, iph[opt->rr+1]);
68 opt->rr = 0;
69 opt->rr_needaddr = 0;
70 }
71 if (opt->ts) {
72 memset(iph+opt->ts, IPOPT_NOP, iph[opt->ts+1]);
73 opt->ts = 0;
74 opt->ts_needaddr = opt->ts_needtime = 0;
75 }
76}
77
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +090078/*
Linus Torvalds1da177e2005-04-16 15:20:36 -070079 * Provided (sopt, skb) points to received options,
80 * build in dopt compiled option set appropriate for answering.
81 * i.e. invert SRR option, copy anothers,
82 * and grab room in RR/TS options.
83 *
84 * NOTE: dopt cannot point to skb.
85 */
86
Eric Dumazetf6d8bd02011-04-21 09:45:37 +000087int ip_options_echo(struct ip_options *dopt, struct sk_buff *skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -070088{
Eric Dumazetf6d8bd02011-04-21 09:45:37 +000089 const struct ip_options *sopt;
Linus Torvalds1da177e2005-04-16 15:20:36 -070090 unsigned char *sptr, *dptr;
91 int soffset, doffset;
92 int optlen;
Al Viroe25d2ca2006-09-27 18:28:47 -070093 __be32 daddr;
Linus Torvalds1da177e2005-04-16 15:20:36 -070094
95 memset(dopt, 0, sizeof(struct ip_options));
96
Linus Torvalds1da177e2005-04-16 15:20:36 -070097 sopt = &(IPCB(skb)->opt);
98
Eric Dumazetf6d8bd02011-04-21 09:45:37 +000099 if (sopt->optlen == 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700100 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700101
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700102 sptr = skb_network_header(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700103 dptr = dopt->__data;
104
Eric Dumazet511c3f92009-06-02 05:14:27 +0000105 daddr = skb_rtable(skb)->rt_spec_dst;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700106
107 if (sopt->rr) {
108 optlen = sptr[sopt->rr+1];
109 soffset = sptr[sopt->rr+2];
110 dopt->rr = dopt->optlen + sizeof(struct iphdr);
111 memcpy(dptr, sptr+sopt->rr, optlen);
112 if (sopt->rr_needaddr && soffset <= optlen) {
113 if (soffset + 3 > optlen)
114 return -EINVAL;
115 dptr[2] = soffset + 4;
116 dopt->rr_needaddr = 1;
117 }
118 dptr += optlen;
119 dopt->optlen += optlen;
120 }
121 if (sopt->ts) {
122 optlen = sptr[sopt->ts+1];
123 soffset = sptr[sopt->ts+2];
124 dopt->ts = dopt->optlen + sizeof(struct iphdr);
125 memcpy(dptr, sptr+sopt->ts, optlen);
126 if (soffset <= optlen) {
127 if (sopt->ts_needaddr) {
128 if (soffset + 3 > optlen)
129 return -EINVAL;
130 dopt->ts_needaddr = 1;
131 soffset += 4;
132 }
133 if (sopt->ts_needtime) {
134 if (soffset + 3 > optlen)
135 return -EINVAL;
136 if ((dptr[3]&0xF) != IPOPT_TS_PRESPEC) {
137 dopt->ts_needtime = 1;
138 soffset += 4;
139 } else {
140 dopt->ts_needtime = 0;
141
Jan Luebbe8628bd82011-03-24 07:44:22 +0000142 if (soffset + 7 <= optlen) {
Al Virofd683222006-09-26 22:17:51 -0700143 __be32 addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700144
Jan Luebbe8628bd82011-03-24 07:44:22 +0000145 memcpy(&addr, dptr+soffset-1, 4);
146 if (inet_addr_type(dev_net(skb_dst(skb)->dev), addr) != RTN_UNICAST) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700147 dopt->ts_needtime = 1;
148 soffset += 8;
149 }
150 }
151 }
152 }
153 dptr[2] = soffset;
154 }
155 dptr += optlen;
156 dopt->optlen += optlen;
157 }
158 if (sopt->srr) {
Eric Dumazetf6d8bd02011-04-21 09:45:37 +0000159 unsigned char *start = sptr+sopt->srr;
Al Viro3ca3c682006-09-27 18:28:07 -0700160 __be32 faddr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700161
162 optlen = start[1];
163 soffset = start[2];
164 doffset = 0;
165 if (soffset > optlen)
166 soffset = optlen + 1;
167 soffset -= 4;
168 if (soffset > 3) {
169 memcpy(&faddr, &start[soffset-1], 4);
170 for (soffset-=4, doffset=4; soffset > 3; soffset-=4, doffset+=4)
171 memcpy(&dptr[doffset-1], &start[soffset-1], 4);
172 /*
173 * RFC1812 requires to fix illegal source routes.
174 */
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -0700175 if (memcmp(&ip_hdr(skb)->saddr,
176 &start[soffset + 3], 4) == 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700177 doffset -= 4;
178 }
179 if (doffset > 3) {
180 memcpy(&start[doffset-1], &daddr, 4);
181 dopt->faddr = faddr;
182 dptr[0] = start[0];
183 dptr[1] = doffset+3;
184 dptr[2] = 4;
185 dptr += doffset+3;
186 dopt->srr = dopt->optlen + sizeof(struct iphdr);
187 dopt->optlen += doffset+3;
188 dopt->is_strictroute = sopt->is_strictroute;
189 }
190 }
Paul Moore11a03f72006-08-03 16:46:20 -0700191 if (sopt->cipso) {
192 optlen = sptr[sopt->cipso+1];
193 dopt->cipso = dopt->optlen+sizeof(struct iphdr);
194 memcpy(dptr, sptr+sopt->cipso, optlen);
195 dptr += optlen;
196 dopt->optlen += optlen;
197 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700198 while (dopt->optlen & 3) {
199 *dptr++ = IPOPT_END;
200 dopt->optlen++;
201 }
202 return 0;
203}
204
205/*
206 * Options "fragmenting", just fill options not
207 * allowed in fragments with NOOPs.
208 * Simple and stupid 8), but the most efficient way.
209 */
210
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +0900211void ip_options_fragment(struct sk_buff * skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700212{
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700213 unsigned char *optptr = skb_network_header(skb) + sizeof(struct iphdr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700214 struct ip_options * opt = &(IPCB(skb)->opt);
215 int l = opt->optlen;
216 int optlen;
217
218 while (l > 0) {
219 switch (*optptr) {
220 case IPOPT_END:
221 return;
222 case IPOPT_NOOP:
223 l--;
224 optptr++;
225 continue;
226 }
227 optlen = optptr[1];
228 if (optlen<2 || optlen>l)
229 return;
230 if (!IPOPT_COPIED(*optptr))
231 memset(optptr, IPOPT_NOOP, optlen);
232 l -= optlen;
233 optptr += optlen;
234 }
235 opt->ts = 0;
236 opt->rr = 0;
237 opt->rr_needaddr = 0;
238 opt->ts_needaddr = 0;
239 opt->ts_needtime = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700240}
241
242/*
243 * Verify options and fill pointers in struct options.
244 * Caller should clear *opt, and set opt->data.
245 * If opt == NULL, then skb->data should point to IP header.
246 */
247
Denis V. Lunev0e6bd4a2008-03-24 15:29:23 -0700248int ip_options_compile(struct net *net,
249 struct ip_options * opt, struct sk_buff * skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700250{
251 int l;
252 unsigned char * iph;
253 unsigned char * optptr;
254 int optlen;
255 unsigned char * pp_ptr = NULL;
Denis V. Lunev22aba382008-03-22 16:36:20 -0700256 struct rtable *rt = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700257
Denis V. Lunev22aba382008-03-22 16:36:20 -0700258 if (skb != NULL) {
Eric Dumazet511c3f92009-06-02 05:14:27 +0000259 rt = skb_rtable(skb);
Denis V. Lunev22aba382008-03-22 16:36:20 -0700260 optptr = (unsigned char *)&(ip_hdr(skb)[1]);
261 } else
Denis V. Lunev10fe7d82008-03-22 16:35:00 -0700262 optptr = opt->__data;
Denis V. Lunev22aba382008-03-22 16:36:20 -0700263 iph = optptr - sizeof(struct iphdr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700264
265 for (l = opt->optlen; l > 0; ) {
266 switch (*optptr) {
267 case IPOPT_END:
268 for (optptr++, l--; l>0; optptr++, l--) {
269 if (*optptr != IPOPT_END) {
270 *optptr = IPOPT_END;
271 opt->is_changed = 1;
272 }
273 }
274 goto eol;
275 case IPOPT_NOOP:
276 l--;
277 optptr++;
278 continue;
279 }
280 optlen = optptr[1];
281 if (optlen<2 || optlen>l) {
282 pp_ptr = optptr;
283 goto error;
284 }
285 switch (*optptr) {
286 case IPOPT_SSRR:
287 case IPOPT_LSRR:
288 if (optlen < 3) {
289 pp_ptr = optptr + 1;
290 goto error;
291 }
292 if (optptr[2] < 4) {
293 pp_ptr = optptr + 2;
294 goto error;
295 }
296 /* NB: cf RFC-1812 5.2.4.1 */
297 if (opt->srr) {
298 pp_ptr = optptr;
299 goto error;
300 }
301 if (!skb) {
302 if (optptr[2] != 4 || optlen < 7 || ((optlen-3) & 3)) {
303 pp_ptr = optptr + 1;
304 goto error;
305 }
306 memcpy(&opt->faddr, &optptr[3], 4);
307 if (optlen > 7)
308 memmove(&optptr[3], &optptr[7], optlen-7);
309 }
310 opt->is_strictroute = (optptr[0] == IPOPT_SSRR);
311 opt->srr = optptr - iph;
312 break;
313 case IPOPT_RR:
314 if (opt->rr) {
315 pp_ptr = optptr;
316 goto error;
317 }
318 if (optlen < 3) {
319 pp_ptr = optptr + 1;
320 goto error;
321 }
322 if (optptr[2] < 4) {
323 pp_ptr = optptr + 2;
324 goto error;
325 }
326 if (optptr[2] <= optlen) {
327 if (optptr[2]+3 > optlen) {
328 pp_ptr = optptr + 2;
329 goto error;
330 }
Eric Dumazetc65353d2011-04-14 05:55:37 +0000331 if (rt) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700332 memcpy(&optptr[optptr[2]-1], &rt->rt_spec_dst, 4);
333 opt->is_changed = 1;
334 }
335 optptr[2] += 4;
336 opt->rr_needaddr = 1;
337 }
338 opt->rr = optptr - iph;
339 break;
340 case IPOPT_TIMESTAMP:
341 if (opt->ts) {
342 pp_ptr = optptr;
343 goto error;
344 }
345 if (optlen < 4) {
346 pp_ptr = optptr + 1;
347 goto error;
348 }
349 if (optptr[2] < 5) {
350 pp_ptr = optptr + 2;
351 goto error;
352 }
353 if (optptr[2] <= optlen) {
Chris Metcalf48bdf0722011-05-29 10:55:44 +0000354 unsigned char *timeptr = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700355 if (optptr[2]+3 > optptr[1]) {
356 pp_ptr = optptr + 2;
357 goto error;
358 }
359 switch (optptr[3]&0xF) {
360 case IPOPT_TS_TSONLY:
361 opt->ts = optptr - iph;
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +0900362 if (skb)
Chris Metcalf48bdf0722011-05-29 10:55:44 +0000363 timeptr = &optptr[optptr[2]-1];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700364 opt->ts_needtime = 1;
365 optptr[2] += 4;
366 break;
367 case IPOPT_TS_TSANDADDR:
368 if (optptr[2]+7 > optptr[1]) {
369 pp_ptr = optptr + 2;
370 goto error;
371 }
372 opt->ts = optptr - iph;
Eric Dumazetc65353d2011-04-14 05:55:37 +0000373 if (rt) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700374 memcpy(&optptr[optptr[2]-1], &rt->rt_spec_dst, 4);
Chris Metcalf48bdf0722011-05-29 10:55:44 +0000375 timeptr = &optptr[optptr[2]+3];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700376 }
377 opt->ts_needaddr = 1;
378 opt->ts_needtime = 1;
379 optptr[2] += 8;
380 break;
381 case IPOPT_TS_PRESPEC:
382 if (optptr[2]+7 > optptr[1]) {
383 pp_ptr = optptr + 2;
384 goto error;
385 }
386 opt->ts = optptr - iph;
387 {
Al Virofd683222006-09-26 22:17:51 -0700388 __be32 addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700389 memcpy(&addr, &optptr[optptr[2]-1], 4);
Denis V. Lunev0e6bd4a2008-03-24 15:29:23 -0700390 if (inet_addr_type(net, addr) == RTN_UNICAST)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700391 break;
392 if (skb)
Chris Metcalf48bdf0722011-05-29 10:55:44 +0000393 timeptr = &optptr[optptr[2]+3];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700394 }
395 opt->ts_needtime = 1;
396 optptr[2] += 8;
397 break;
398 default:
399 if (!skb && !capable(CAP_NET_RAW)) {
400 pp_ptr = optptr + 3;
401 goto error;
402 }
403 break;
404 }
405 if (timeptr) {
YOSHIFUJI Hideakif25c3d62008-04-21 02:34:08 -0700406 struct timespec tv;
Chris Metcalf48bdf0722011-05-29 10:55:44 +0000407 u32 midtime;
YOSHIFUJI Hideakif25c3d62008-04-21 02:34:08 -0700408 getnstimeofday(&tv);
Chris Metcalf48bdf0722011-05-29 10:55:44 +0000409 midtime = (tv.tv_sec % 86400) * MSEC_PER_SEC + tv.tv_nsec / NSEC_PER_MSEC;
410 put_unaligned_be32(midtime, timeptr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700411 opt->is_changed = 1;
412 }
413 } else {
414 unsigned overflow = optptr[3]>>4;
415 if (overflow == 15) {
416 pp_ptr = optptr + 3;
417 goto error;
418 }
419 opt->ts = optptr - iph;
420 if (skb) {
421 optptr[3] = (optptr[3]&0xF)|((overflow+1)<<4);
422 opt->is_changed = 1;
423 }
424 }
425 break;
426 case IPOPT_RA:
427 if (optlen < 4) {
428 pp_ptr = optptr + 1;
429 goto error;
430 }
431 if (optptr[2] == 0 && optptr[3] == 0)
432 opt->router_alert = optptr - iph;
433 break;
Paul Moore11a03f72006-08-03 16:46:20 -0700434 case IPOPT_CIPSO:
Paul Mooref8687af2006-10-30 15:22:15 -0800435 if ((!skb && !capable(CAP_NET_RAW)) || opt->cipso) {
Paul Moore11a03f72006-08-03 16:46:20 -0700436 pp_ptr = optptr;
437 goto error;
438 }
439 opt->cipso = optptr - iph;
Paul Moore15c45f72008-10-10 10:16:34 -0400440 if (cipso_v4_validate(skb, &optptr)) {
Paul Moore11a03f72006-08-03 16:46:20 -0700441 pp_ptr = optptr;
442 goto error;
443 }
444 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700445 case IPOPT_SEC:
446 case IPOPT_SID:
447 default:
448 if (!skb && !capable(CAP_NET_RAW)) {
449 pp_ptr = optptr;
450 goto error;
451 }
452 break;
453 }
454 l -= optlen;
455 optptr += optlen;
456 }
457
458eol:
459 if (!pp_ptr)
460 return 0;
461
462error:
463 if (skb) {
464 icmp_send(skb, ICMP_PARAMETERPROB, 0, htonl((pp_ptr-iph)<<24));
465 }
466 return -EINVAL;
467}
Bandan Das462fb2a2010-09-19 09:34:33 +0000468EXPORT_SYMBOL(ip_options_compile);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700469
470/*
471 * Undo all the changes done by ip_options_compile().
472 */
473
474void ip_options_undo(struct ip_options * opt)
475{
476 if (opt->srr) {
477 unsigned char * optptr = opt->__data+opt->srr-sizeof(struct iphdr);
478 memmove(optptr+7, optptr+3, optptr[1]-7);
479 memcpy(optptr+3, &opt->faddr, 4);
480 }
481 if (opt->rr_needaddr) {
482 unsigned char * optptr = opt->__data+opt->rr-sizeof(struct iphdr);
483 optptr[2] -= 4;
484 memset(&optptr[optptr[2]-1], 0, 4);
485 }
486 if (opt->ts) {
487 unsigned char * optptr = opt->__data+opt->ts-sizeof(struct iphdr);
488 if (opt->ts_needtime) {
489 optptr[2] -= 4;
490 memset(&optptr[optptr[2]-1], 0, 4);
491 if ((optptr[3]&0xF) == IPOPT_TS_PRESPEC)
492 optptr[2] -= 4;
493 }
494 if (opt->ts_needaddr) {
495 optptr[2] -= 4;
496 memset(&optptr[optptr[2]-1], 0, 4);
497 }
498 }
499}
500
Eric Dumazetf6d8bd02011-04-21 09:45:37 +0000501static struct ip_options_rcu *ip_options_get_alloc(const int optlen)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700502{
Eric Dumazetf6d8bd02011-04-21 09:45:37 +0000503 return kzalloc(sizeof(struct ip_options_rcu) + ((optlen + 3) & ~3),
Mariusz Kozlowski37640702007-07-31 14:06:45 -0700504 GFP_KERNEL);
Arnaldo Carvalho de Melo4c6ea292005-08-16 19:46:48 -0300505}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700506
Eric Dumazetf6d8bd02011-04-21 09:45:37 +0000507static int ip_options_get_finish(struct net *net, struct ip_options_rcu **optp,
508 struct ip_options_rcu *opt, int optlen)
Arnaldo Carvalho de Melo4c6ea292005-08-16 19:46:48 -0300509{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700510 while (optlen & 3)
Eric Dumazetf6d8bd02011-04-21 09:45:37 +0000511 opt->opt.__data[optlen++] = IPOPT_END;
512 opt->opt.optlen = optlen;
513 if (optlen && ip_options_compile(net, &opt->opt, NULL)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700514 kfree(opt);
515 return -EINVAL;
516 }
Jesper Juhla51482b2005-11-08 09:41:34 -0800517 kfree(*optp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700518 *optp = opt;
519 return 0;
520}
521
Eric Dumazetf6d8bd02011-04-21 09:45:37 +0000522int ip_options_get_from_user(struct net *net, struct ip_options_rcu **optp,
Denis V. Lunevf2c48022008-03-24 15:29:55 -0700523 unsigned char __user *data, int optlen)
Arnaldo Carvalho de Melo4c6ea292005-08-16 19:46:48 -0300524{
Eric Dumazetf6d8bd02011-04-21 09:45:37 +0000525 struct ip_options_rcu *opt = ip_options_get_alloc(optlen);
Arnaldo Carvalho de Melo4c6ea292005-08-16 19:46:48 -0300526
527 if (!opt)
528 return -ENOMEM;
Eric Dumazetf6d8bd02011-04-21 09:45:37 +0000529 if (optlen && copy_from_user(opt->opt.__data, data, optlen)) {
Arnaldo Carvalho de Melo4c6ea292005-08-16 19:46:48 -0300530 kfree(opt);
531 return -EFAULT;
532 }
Denis V. Lunevf2c48022008-03-24 15:29:55 -0700533 return ip_options_get_finish(net, optp, opt, optlen);
Arnaldo Carvalho de Melo4c6ea292005-08-16 19:46:48 -0300534}
535
Eric Dumazetf6d8bd02011-04-21 09:45:37 +0000536int ip_options_get(struct net *net, struct ip_options_rcu **optp,
Denis V. Lunevf2c48022008-03-24 15:29:55 -0700537 unsigned char *data, int optlen)
Arnaldo Carvalho de Melo4c6ea292005-08-16 19:46:48 -0300538{
Eric Dumazetf6d8bd02011-04-21 09:45:37 +0000539 struct ip_options_rcu *opt = ip_options_get_alloc(optlen);
Arnaldo Carvalho de Melo4c6ea292005-08-16 19:46:48 -0300540
541 if (!opt)
542 return -ENOMEM;
543 if (optlen)
Eric Dumazetf6d8bd02011-04-21 09:45:37 +0000544 memcpy(opt->opt.__data, data, optlen);
Denis V. Lunevf2c48022008-03-24 15:29:55 -0700545 return ip_options_get_finish(net, optp, opt, optlen);
Arnaldo Carvalho de Melo4c6ea292005-08-16 19:46:48 -0300546}
547
Linus Torvalds1da177e2005-04-16 15:20:36 -0700548void ip_forward_options(struct sk_buff *skb)
549{
550 struct ip_options * opt = &(IPCB(skb)->opt);
551 unsigned char * optptr;
Eric Dumazet511c3f92009-06-02 05:14:27 +0000552 struct rtable *rt = skb_rtable(skb);
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700553 unsigned char *raw = skb_network_header(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700554
555 if (opt->rr_needaddr) {
556 optptr = (unsigned char *)raw + opt->rr;
David S. Miller8e363602011-05-13 17:29:41 -0400557 ip_rt_get_source(&optptr[optptr[2]-5], skb, rt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700558 opt->is_changed = 1;
559 }
560 if (opt->srr_is_hit) {
561 int srrptr, srrspace;
562
563 optptr = raw + opt->srr;
564
565 for ( srrptr=optptr[2], srrspace = optptr[1];
566 srrptr <= srrspace;
567 srrptr += 4
568 ) {
569 if (srrptr + 3 > srrspace)
570 break;
David S. Miller7be799a2011-05-13 17:31:02 -0400571 if (memcmp(&ip_hdr(skb)->daddr, &optptr[srrptr-1], 4) == 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700572 break;
573 }
574 if (srrptr + 3 <= srrspace) {
575 opt->is_changed = 1;
David S. Miller8e363602011-05-13 17:29:41 -0400576 ip_rt_get_source(&optptr[srrptr-1], skb, rt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700577 optptr[2] = srrptr+4;
578 } else if (net_ratelimit())
579 printk(KERN_CRIT "ip_forward(): Argh! Destination lost!\n");
580 if (opt->ts_needaddr) {
581 optptr = raw + opt->ts;
David S. Miller8e363602011-05-13 17:29:41 -0400582 ip_rt_get_source(&optptr[optptr[2]-9], skb, rt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700583 opt->is_changed = 1;
584 }
585 }
586 if (opt->is_changed) {
587 opt->is_changed = 0;
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -0700588 ip_send_check(ip_hdr(skb));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700589 }
590}
591
592int ip_options_rcv_srr(struct sk_buff *skb)
593{
594 struct ip_options *opt = &(IPCB(skb)->opt);
595 int srrspace, srrptr;
Al Viro9e12bb22006-09-26 21:25:20 -0700596 __be32 nexthop;
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -0700597 struct iphdr *iph = ip_hdr(skb);
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700598 unsigned char *optptr = skb_network_header(skb) + opt->srr;
Eric Dumazet511c3f92009-06-02 05:14:27 +0000599 struct rtable *rt = skb_rtable(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700600 struct rtable *rt2;
Eric Dumazet7fee2262010-05-11 23:19:48 +0000601 unsigned long orefdst;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700602 int err;
603
David S. Miller10949552011-05-12 19:26:57 -0400604 if (!rt)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700605 return 0;
606
607 if (skb->pkt_type != PACKET_HOST)
608 return -EINVAL;
609 if (rt->rt_type == RTN_UNICAST) {
610 if (!opt->is_strictroute)
611 return 0;
612 icmp_send(skb, ICMP_PARAMETERPROB, 0, htonl(16<<24));
613 return -EINVAL;
614 }
615 if (rt->rt_type != RTN_LOCAL)
616 return -EINVAL;
617
618 for (srrptr=optptr[2], srrspace = optptr[1]; srrptr <= srrspace; srrptr += 4) {
619 if (srrptr + 3 > srrspace) {
620 icmp_send(skb, ICMP_PARAMETERPROB, 0, htonl((opt->srr+2)<<24));
621 return -EINVAL;
622 }
623 memcpy(&nexthop, &optptr[srrptr-1], 4);
624
Eric Dumazet7fee2262010-05-11 23:19:48 +0000625 orefdst = skb->_skb_refdst;
Eric Dumazetadf30902009-06-02 05:19:30 +0000626 skb_dst_set(skb, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700627 err = ip_route_input(skb, nexthop, iph->saddr, iph->tos, skb->dev);
Eric Dumazet511c3f92009-06-02 05:14:27 +0000628 rt2 = skb_rtable(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700629 if (err || (rt2->rt_type != RTN_UNICAST && rt2->rt_type != RTN_LOCAL)) {
Eric Dumazet7fee2262010-05-11 23:19:48 +0000630 skb_dst_drop(skb);
631 skb->_skb_refdst = orefdst;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700632 return -EINVAL;
633 }
Eric Dumazet7fee2262010-05-11 23:19:48 +0000634 refdst_drop(orefdst);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700635 if (rt2->rt_type != RTN_LOCAL)
636 break;
637 /* Superfast 8) loopback forward */
David S. Millerc30883b2011-05-12 19:30:58 -0400638 iph->daddr = nexthop;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700639 opt->is_changed = 1;
640 }
641 if (srrptr <= srrspace) {
642 opt->srr_is_hit = 1;
643 opt->is_changed = 1;
644 }
645 return 0;
646}
Bandan Das462fb2a2010-09-19 09:34:33 +0000647EXPORT_SYMBOL(ip_options_rcv_srr);