Commit | Line | Data |
---|---|---|
1da177e4 LT |
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 options processing module for ip.c | |
7 | * | |
8 | * Version: $Id: ip_options.c,v 1.21 2001/09/01 00:31:50 davem Exp $ | |
9 | * | |
10 | * Authors: A.N.Kuznetsov | |
e905a9ed | 11 | * |
1da177e4 LT |
12 | */ |
13 | ||
4fc268d2 | 14 | #include <linux/capability.h> |
1da177e4 LT |
15 | #include <linux/module.h> |
16 | #include <linux/types.h> | |
17 | #include <asm/uaccess.h> | |
18 | #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> | |
14c85021 | 26 | #include <net/route.h> |
11a03f78 | 27 | #include <net/cipso_ipv4.h> |
1da177e4 | 28 | |
e905a9ed | 29 | /* |
1da177e4 LT |
30 | * 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 | ||
40 | void ip_options_build(struct sk_buff * skb, struct ip_options * opt, | |
8712f774 | 41 | __be32 daddr, struct rtable *rt, int is_frag) |
1da177e4 | 42 | { |
d56f90a7 | 43 | unsigned char *iph = skb_network_header(skb); |
1da177e4 LT |
44 | |
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); | |
1da177e4 LT |
48 | |
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) | |
54 | ip_rt_get_source(iph+opt->rr+iph[opt->rr+2]-5, rt); | |
55 | if (opt->ts_needaddr) | |
56 | ip_rt_get_source(iph+opt->ts+iph[opt->ts+2]-9, rt); | |
57 | if (opt->ts_needtime) { | |
58 | struct timeval tv; | |
e25d2ca6 | 59 | __be32 midtime; |
1da177e4 LT |
60 | do_gettimeofday(&tv); |
61 | midtime = htonl((tv.tv_sec % 86400) * 1000 + tv.tv_usec / 1000); | |
62 | 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 | ||
e905a9ed | 78 | /* |
1da177e4 LT |
79 | * 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 | ||
e905a9ed | 87 | int ip_options_echo(struct ip_options * dopt, struct sk_buff * skb) |
1da177e4 LT |
88 | { |
89 | struct ip_options *sopt; | |
90 | unsigned char *sptr, *dptr; | |
91 | int soffset, doffset; | |
92 | int optlen; | |
e25d2ca6 | 93 | __be32 daddr; |
1da177e4 LT |
94 | |
95 | memset(dopt, 0, sizeof(struct ip_options)); | |
96 | ||
1da177e4 LT |
97 | sopt = &(IPCB(skb)->opt); |
98 | ||
99 | if (sopt->optlen == 0) { | |
100 | dopt->optlen = 0; | |
101 | return 0; | |
102 | } | |
103 | ||
d56f90a7 | 104 | sptr = skb_network_header(skb); |
1da177e4 LT |
105 | dptr = dopt->__data; |
106 | ||
ee6b9673 | 107 | daddr = skb->rtable->rt_spec_dst; |
1da177e4 LT |
108 | |
109 | if (sopt->rr) { | |
110 | optlen = sptr[sopt->rr+1]; | |
111 | soffset = sptr[sopt->rr+2]; | |
112 | dopt->rr = dopt->optlen + sizeof(struct iphdr); | |
113 | memcpy(dptr, sptr+sopt->rr, optlen); | |
114 | if (sopt->rr_needaddr && soffset <= optlen) { | |
115 | if (soffset + 3 > optlen) | |
116 | return -EINVAL; | |
117 | dptr[2] = soffset + 4; | |
118 | dopt->rr_needaddr = 1; | |
119 | } | |
120 | dptr += optlen; | |
121 | dopt->optlen += optlen; | |
122 | } | |
123 | if (sopt->ts) { | |
124 | optlen = sptr[sopt->ts+1]; | |
125 | soffset = sptr[sopt->ts+2]; | |
126 | dopt->ts = dopt->optlen + sizeof(struct iphdr); | |
127 | memcpy(dptr, sptr+sopt->ts, optlen); | |
128 | if (soffset <= optlen) { | |
129 | if (sopt->ts_needaddr) { | |
130 | if (soffset + 3 > optlen) | |
131 | return -EINVAL; | |
132 | dopt->ts_needaddr = 1; | |
133 | soffset += 4; | |
134 | } | |
135 | if (sopt->ts_needtime) { | |
136 | if (soffset + 3 > optlen) | |
137 | return -EINVAL; | |
138 | if ((dptr[3]&0xF) != IPOPT_TS_PRESPEC) { | |
139 | dopt->ts_needtime = 1; | |
140 | soffset += 4; | |
141 | } else { | |
142 | dopt->ts_needtime = 0; | |
143 | ||
144 | if (soffset + 8 <= optlen) { | |
fd683222 | 145 | __be32 addr; |
1da177e4 LT |
146 | |
147 | memcpy(&addr, sptr+soffset-1, 4); | |
6b175b26 | 148 | if (inet_addr_type(&init_net, addr) != RTN_LOCAL) { |
1da177e4 LT |
149 | dopt->ts_needtime = 1; |
150 | soffset += 8; | |
151 | } | |
152 | } | |
153 | } | |
154 | } | |
155 | dptr[2] = soffset; | |
156 | } | |
157 | dptr += optlen; | |
158 | dopt->optlen += optlen; | |
159 | } | |
160 | if (sopt->srr) { | |
161 | unsigned char * start = sptr+sopt->srr; | |
3ca3c68e | 162 | __be32 faddr; |
1da177e4 LT |
163 | |
164 | optlen = start[1]; | |
165 | soffset = start[2]; | |
166 | doffset = 0; | |
167 | if (soffset > optlen) | |
168 | soffset = optlen + 1; | |
169 | soffset -= 4; | |
170 | if (soffset > 3) { | |
171 | memcpy(&faddr, &start[soffset-1], 4); | |
172 | for (soffset-=4, doffset=4; soffset > 3; soffset-=4, doffset+=4) | |
173 | memcpy(&dptr[doffset-1], &start[soffset-1], 4); | |
174 | /* | |
175 | * RFC1812 requires to fix illegal source routes. | |
176 | */ | |
eddc9ec5 ACM |
177 | if (memcmp(&ip_hdr(skb)->saddr, |
178 | &start[soffset + 3], 4) == 0) | |
1da177e4 LT |
179 | doffset -= 4; |
180 | } | |
181 | if (doffset > 3) { | |
182 | memcpy(&start[doffset-1], &daddr, 4); | |
183 | dopt->faddr = faddr; | |
184 | dptr[0] = start[0]; | |
185 | dptr[1] = doffset+3; | |
186 | dptr[2] = 4; | |
187 | dptr += doffset+3; | |
188 | dopt->srr = dopt->optlen + sizeof(struct iphdr); | |
189 | dopt->optlen += doffset+3; | |
190 | dopt->is_strictroute = sopt->is_strictroute; | |
191 | } | |
192 | } | |
11a03f78 PM |
193 | if (sopt->cipso) { |
194 | optlen = sptr[sopt->cipso+1]; | |
195 | dopt->cipso = dopt->optlen+sizeof(struct iphdr); | |
196 | memcpy(dptr, sptr+sopt->cipso, optlen); | |
197 | dptr += optlen; | |
198 | dopt->optlen += optlen; | |
199 | } | |
1da177e4 LT |
200 | while (dopt->optlen & 3) { |
201 | *dptr++ = IPOPT_END; | |
202 | dopt->optlen++; | |
203 | } | |
204 | return 0; | |
205 | } | |
206 | ||
207 | /* | |
208 | * Options "fragmenting", just fill options not | |
209 | * allowed in fragments with NOOPs. | |
210 | * Simple and stupid 8), but the most efficient way. | |
211 | */ | |
212 | ||
e905a9ed | 213 | void ip_options_fragment(struct sk_buff * skb) |
1da177e4 | 214 | { |
d56f90a7 | 215 | unsigned char *optptr = skb_network_header(skb) + sizeof(struct iphdr); |
1da177e4 LT |
216 | struct ip_options * opt = &(IPCB(skb)->opt); |
217 | int l = opt->optlen; | |
218 | int optlen; | |
219 | ||
220 | while (l > 0) { | |
221 | switch (*optptr) { | |
222 | case IPOPT_END: | |
223 | return; | |
224 | case IPOPT_NOOP: | |
225 | l--; | |
226 | optptr++; | |
227 | continue; | |
228 | } | |
229 | optlen = optptr[1]; | |
230 | if (optlen<2 || optlen>l) | |
231 | return; | |
232 | if (!IPOPT_COPIED(*optptr)) | |
233 | memset(optptr, IPOPT_NOOP, optlen); | |
234 | l -= optlen; | |
235 | optptr += optlen; | |
236 | } | |
237 | opt->ts = 0; | |
238 | opt->rr = 0; | |
239 | opt->rr_needaddr = 0; | |
240 | opt->ts_needaddr = 0; | |
241 | opt->ts_needtime = 0; | |
242 | return; | |
243 | } | |
244 | ||
245 | /* | |
246 | * Verify options and fill pointers in struct options. | |
247 | * Caller should clear *opt, and set opt->data. | |
248 | * If opt == NULL, then skb->data should point to IP header. | |
249 | */ | |
250 | ||
251 | int ip_options_compile(struct ip_options * opt, struct sk_buff * skb) | |
252 | { | |
253 | int l; | |
254 | unsigned char * iph; | |
255 | unsigned char * optptr; | |
256 | int optlen; | |
257 | unsigned char * pp_ptr = NULL; | |
22aba383 | 258 | struct rtable *rt = NULL; |
1da177e4 | 259 | |
22aba383 DL |
260 | if (skb != NULL) { |
261 | rt = skb->rtable; | |
262 | optptr = (unsigned char *)&(ip_hdr(skb)[1]); | |
263 | } else | |
10fe7d85 | 264 | optptr = opt->__data; |
22aba383 | 265 | iph = optptr - sizeof(struct iphdr); |
1da177e4 LT |
266 | |
267 | for (l = opt->optlen; l > 0; ) { | |
268 | switch (*optptr) { | |
269 | case IPOPT_END: | |
270 | for (optptr++, l--; l>0; optptr++, l--) { | |
271 | if (*optptr != IPOPT_END) { | |
272 | *optptr = IPOPT_END; | |
273 | opt->is_changed = 1; | |
274 | } | |
275 | } | |
276 | goto eol; | |
277 | case IPOPT_NOOP: | |
278 | l--; | |
279 | optptr++; | |
280 | continue; | |
281 | } | |
282 | optlen = optptr[1]; | |
283 | if (optlen<2 || optlen>l) { | |
284 | pp_ptr = optptr; | |
285 | goto error; | |
286 | } | |
287 | switch (*optptr) { | |
288 | case IPOPT_SSRR: | |
289 | case IPOPT_LSRR: | |
290 | if (optlen < 3) { | |
291 | pp_ptr = optptr + 1; | |
292 | goto error; | |
293 | } | |
294 | if (optptr[2] < 4) { | |
295 | pp_ptr = optptr + 2; | |
296 | goto error; | |
297 | } | |
298 | /* NB: cf RFC-1812 5.2.4.1 */ | |
299 | if (opt->srr) { | |
300 | pp_ptr = optptr; | |
301 | goto error; | |
302 | } | |
303 | if (!skb) { | |
304 | if (optptr[2] != 4 || optlen < 7 || ((optlen-3) & 3)) { | |
305 | pp_ptr = optptr + 1; | |
306 | goto error; | |
307 | } | |
308 | memcpy(&opt->faddr, &optptr[3], 4); | |
309 | if (optlen > 7) | |
310 | memmove(&optptr[3], &optptr[7], optlen-7); | |
311 | } | |
312 | opt->is_strictroute = (optptr[0] == IPOPT_SSRR); | |
313 | opt->srr = optptr - iph; | |
314 | break; | |
315 | case IPOPT_RR: | |
316 | if (opt->rr) { | |
317 | pp_ptr = optptr; | |
318 | goto error; | |
319 | } | |
320 | if (optlen < 3) { | |
321 | pp_ptr = optptr + 1; | |
322 | goto error; | |
323 | } | |
324 | if (optptr[2] < 4) { | |
325 | pp_ptr = optptr + 2; | |
326 | goto error; | |
327 | } | |
328 | if (optptr[2] <= optlen) { | |
329 | if (optptr[2]+3 > optlen) { | |
330 | pp_ptr = optptr + 2; | |
331 | goto error; | |
332 | } | |
333 | if (skb) { | |
334 | memcpy(&optptr[optptr[2]-1], &rt->rt_spec_dst, 4); | |
335 | opt->is_changed = 1; | |
336 | } | |
337 | optptr[2] += 4; | |
338 | opt->rr_needaddr = 1; | |
339 | } | |
340 | opt->rr = optptr - iph; | |
341 | break; | |
342 | case IPOPT_TIMESTAMP: | |
343 | if (opt->ts) { | |
344 | pp_ptr = optptr; | |
345 | goto error; | |
346 | } | |
347 | if (optlen < 4) { | |
348 | pp_ptr = optptr + 1; | |
349 | goto error; | |
350 | } | |
351 | if (optptr[2] < 5) { | |
352 | pp_ptr = optptr + 2; | |
353 | goto error; | |
354 | } | |
355 | if (optptr[2] <= optlen) { | |
e25d2ca6 | 356 | __be32 *timeptr = NULL; |
1da177e4 LT |
357 | if (optptr[2]+3 > optptr[1]) { |
358 | pp_ptr = optptr + 2; | |
359 | goto error; | |
360 | } | |
361 | switch (optptr[3]&0xF) { | |
362 | case IPOPT_TS_TSONLY: | |
363 | opt->ts = optptr - iph; | |
e905a9ed | 364 | if (skb) |
e25d2ca6 | 365 | timeptr = (__be32*)&optptr[optptr[2]-1]; |
1da177e4 LT |
366 | opt->ts_needtime = 1; |
367 | optptr[2] += 4; | |
368 | break; | |
369 | case IPOPT_TS_TSANDADDR: | |
370 | if (optptr[2]+7 > optptr[1]) { | |
371 | pp_ptr = optptr + 2; | |
372 | goto error; | |
373 | } | |
374 | opt->ts = optptr - iph; | |
375 | if (skb) { | |
376 | memcpy(&optptr[optptr[2]-1], &rt->rt_spec_dst, 4); | |
e25d2ca6 | 377 | timeptr = (__be32*)&optptr[optptr[2]+3]; |
1da177e4 LT |
378 | } |
379 | opt->ts_needaddr = 1; | |
380 | opt->ts_needtime = 1; | |
381 | optptr[2] += 8; | |
382 | break; | |
383 | case IPOPT_TS_PRESPEC: | |
384 | if (optptr[2]+7 > optptr[1]) { | |
385 | pp_ptr = optptr + 2; | |
386 | goto error; | |
387 | } | |
388 | opt->ts = optptr - iph; | |
389 | { | |
fd683222 | 390 | __be32 addr; |
1da177e4 | 391 | memcpy(&addr, &optptr[optptr[2]-1], 4); |
6b175b26 | 392 | if (inet_addr_type(&init_net, addr) == RTN_UNICAST) |
1da177e4 LT |
393 | break; |
394 | if (skb) | |
e25d2ca6 | 395 | timeptr = (__be32*)&optptr[optptr[2]+3]; |
1da177e4 LT |
396 | } |
397 | opt->ts_needtime = 1; | |
398 | optptr[2] += 8; | |
399 | break; | |
400 | default: | |
401 | if (!skb && !capable(CAP_NET_RAW)) { | |
402 | pp_ptr = optptr + 3; | |
403 | goto error; | |
404 | } | |
405 | break; | |
406 | } | |
407 | if (timeptr) { | |
408 | struct timeval tv; | |
e25d2ca6 | 409 | __be32 midtime; |
1da177e4 LT |
410 | do_gettimeofday(&tv); |
411 | midtime = htonl((tv.tv_sec % 86400) * 1000 + tv.tv_usec / 1000); | |
e25d2ca6 | 412 | memcpy(timeptr, &midtime, sizeof(__be32)); |
1da177e4 LT |
413 | opt->is_changed = 1; |
414 | } | |
415 | } else { | |
416 | unsigned overflow = optptr[3]>>4; | |
417 | if (overflow == 15) { | |
418 | pp_ptr = optptr + 3; | |
419 | goto error; | |
420 | } | |
421 | opt->ts = optptr - iph; | |
422 | if (skb) { | |
423 | optptr[3] = (optptr[3]&0xF)|((overflow+1)<<4); | |
424 | opt->is_changed = 1; | |
425 | } | |
426 | } | |
427 | break; | |
428 | case IPOPT_RA: | |
429 | if (optlen < 4) { | |
430 | pp_ptr = optptr + 1; | |
431 | goto error; | |
432 | } | |
433 | if (optptr[2] == 0 && optptr[3] == 0) | |
434 | opt->router_alert = optptr - iph; | |
435 | break; | |
11a03f78 | 436 | case IPOPT_CIPSO: |
f8687afe | 437 | if ((!skb && !capable(CAP_NET_RAW)) || opt->cipso) { |
11a03f78 PM |
438 | pp_ptr = optptr; |
439 | goto error; | |
440 | } | |
441 | opt->cipso = optptr - iph; | |
e905a9ed | 442 | if (cipso_v4_validate(&optptr)) { |
11a03f78 PM |
443 | pp_ptr = optptr; |
444 | goto error; | |
445 | } | |
446 | break; | |
1da177e4 LT |
447 | case IPOPT_SEC: |
448 | case IPOPT_SID: | |
449 | default: | |
450 | if (!skb && !capable(CAP_NET_RAW)) { | |
451 | pp_ptr = optptr; | |
452 | goto error; | |
453 | } | |
454 | break; | |
455 | } | |
456 | l -= optlen; | |
457 | optptr += optlen; | |
458 | } | |
459 | ||
460 | eol: | |
461 | if (!pp_ptr) | |
462 | return 0; | |
463 | ||
464 | error: | |
465 | if (skb) { | |
466 | icmp_send(skb, ICMP_PARAMETERPROB, 0, htonl((pp_ptr-iph)<<24)); | |
467 | } | |
468 | return -EINVAL; | |
469 | } | |
470 | ||
471 | ||
472 | /* | |
473 | * Undo all the changes done by ip_options_compile(). | |
474 | */ | |
475 | ||
476 | void ip_options_undo(struct ip_options * opt) | |
477 | { | |
478 | if (opt->srr) { | |
479 | unsigned char * optptr = opt->__data+opt->srr-sizeof(struct iphdr); | |
480 | memmove(optptr+7, optptr+3, optptr[1]-7); | |
481 | memcpy(optptr+3, &opt->faddr, 4); | |
482 | } | |
483 | if (opt->rr_needaddr) { | |
484 | unsigned char * optptr = opt->__data+opt->rr-sizeof(struct iphdr); | |
485 | optptr[2] -= 4; | |
486 | memset(&optptr[optptr[2]-1], 0, 4); | |
487 | } | |
488 | if (opt->ts) { | |
489 | unsigned char * optptr = opt->__data+opt->ts-sizeof(struct iphdr); | |
490 | if (opt->ts_needtime) { | |
491 | optptr[2] -= 4; | |
492 | memset(&optptr[optptr[2]-1], 0, 4); | |
493 | if ((optptr[3]&0xF) == IPOPT_TS_PRESPEC) | |
494 | optptr[2] -= 4; | |
495 | } | |
496 | if (opt->ts_needaddr) { | |
497 | optptr[2] -= 4; | |
498 | memset(&optptr[optptr[2]-1], 0, 4); | |
499 | } | |
500 | } | |
501 | } | |
502 | ||
4c6ea29d | 503 | static struct ip_options *ip_options_get_alloc(const int optlen) |
1da177e4 | 504 | { |
37640703 MK |
505 | return kzalloc(sizeof(struct ip_options) + ((optlen + 3) & ~3), |
506 | GFP_KERNEL); | |
4c6ea29d | 507 | } |
1da177e4 | 508 | |
4c6ea29d ACM |
509 | static int ip_options_get_finish(struct ip_options **optp, |
510 | struct ip_options *opt, int optlen) | |
511 | { | |
1da177e4 LT |
512 | while (optlen & 3) |
513 | opt->__data[optlen++] = IPOPT_END; | |
514 | opt->optlen = optlen; | |
1da177e4 LT |
515 | if (optlen && ip_options_compile(opt, NULL)) { |
516 | kfree(opt); | |
517 | return -EINVAL; | |
518 | } | |
a51482bd | 519 | kfree(*optp); |
1da177e4 LT |
520 | *optp = opt; |
521 | return 0; | |
522 | } | |
523 | ||
4c6ea29d ACM |
524 | int ip_options_get_from_user(struct ip_options **optp, unsigned char __user *data, int optlen) |
525 | { | |
526 | struct ip_options *opt = ip_options_get_alloc(optlen); | |
527 | ||
528 | if (!opt) | |
529 | return -ENOMEM; | |
530 | if (optlen && copy_from_user(opt->__data, data, optlen)) { | |
531 | kfree(opt); | |
532 | return -EFAULT; | |
533 | } | |
534 | return ip_options_get_finish(optp, opt, optlen); | |
535 | } | |
536 | ||
537 | int ip_options_get(struct ip_options **optp, unsigned char *data, int optlen) | |
538 | { | |
539 | struct ip_options *opt = ip_options_get_alloc(optlen); | |
540 | ||
541 | if (!opt) | |
542 | return -ENOMEM; | |
543 | if (optlen) | |
544 | memcpy(opt->__data, data, optlen); | |
545 | return ip_options_get_finish(optp, opt, optlen); | |
546 | } | |
547 | ||
1da177e4 LT |
548 | void ip_forward_options(struct sk_buff *skb) |
549 | { | |
550 | struct ip_options * opt = &(IPCB(skb)->opt); | |
551 | unsigned char * optptr; | |
ee6b9673 | 552 | struct rtable *rt = skb->rtable; |
d56f90a7 | 553 | unsigned char *raw = skb_network_header(skb); |
1da177e4 LT |
554 | |
555 | if (opt->rr_needaddr) { | |
556 | optptr = (unsigned char *)raw + opt->rr; | |
557 | ip_rt_get_source(&optptr[optptr[2]-5], rt); | |
558 | 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; | |
571 | if (memcmp(&rt->rt_dst, &optptr[srrptr-1], 4) == 0) | |
572 | break; | |
573 | } | |
574 | if (srrptr + 3 <= srrspace) { | |
575 | opt->is_changed = 1; | |
576 | ip_rt_get_source(&optptr[srrptr-1], rt); | |
eddc9ec5 | 577 | ip_hdr(skb)->daddr = rt->rt_dst; |
1da177e4 LT |
578 | optptr[2] = srrptr+4; |
579 | } else if (net_ratelimit()) | |
580 | printk(KERN_CRIT "ip_forward(): Argh! Destination lost!\n"); | |
581 | if (opt->ts_needaddr) { | |
582 | optptr = raw + opt->ts; | |
583 | ip_rt_get_source(&optptr[optptr[2]-9], rt); | |
584 | opt->is_changed = 1; | |
585 | } | |
586 | } | |
587 | if (opt->is_changed) { | |
588 | opt->is_changed = 0; | |
eddc9ec5 | 589 | ip_send_check(ip_hdr(skb)); |
1da177e4 LT |
590 | } |
591 | } | |
592 | ||
593 | int ip_options_rcv_srr(struct sk_buff *skb) | |
594 | { | |
595 | struct ip_options *opt = &(IPCB(skb)->opt); | |
596 | int srrspace, srrptr; | |
9e12bb22 | 597 | __be32 nexthop; |
eddc9ec5 | 598 | struct iphdr *iph = ip_hdr(skb); |
d56f90a7 | 599 | unsigned char *optptr = skb_network_header(skb) + opt->srr; |
ee6b9673 | 600 | struct rtable *rt = skb->rtable; |
1da177e4 LT |
601 | struct rtable *rt2; |
602 | int err; | |
603 | ||
604 | if (!opt->srr) | |
605 | 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 | ||
ee6b9673 ED |
625 | rt = skb->rtable; |
626 | skb->rtable = NULL; | |
1da177e4 | 627 | err = ip_route_input(skb, nexthop, iph->saddr, iph->tos, skb->dev); |
ee6b9673 | 628 | rt2 = skb->rtable; |
1da177e4 LT |
629 | if (err || (rt2->rt_type != RTN_UNICAST && rt2->rt_type != RTN_LOCAL)) { |
630 | ip_rt_put(rt2); | |
ee6b9673 | 631 | skb->rtable = rt; |
1da177e4 LT |
632 | return -EINVAL; |
633 | } | |
634 | ip_rt_put(rt); | |
635 | if (rt2->rt_type != RTN_LOCAL) | |
636 | break; | |
637 | /* Superfast 8) loopback forward */ | |
638 | memcpy(&iph->daddr, &optptr[srrptr-1], 4); | |
639 | 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 | } |