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 | |
11 | * | |
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 LT |
28 | |
29 | /* | |
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 LT |
42 | { |
43 | unsigned char * iph = skb->nh.raw; | |
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); | |
48 | opt->is_data = 0; | |
49 | ||
50 | if (opt->srr) | |
51 | memcpy(iph+opt->srr+iph[opt->srr+1]-4, &daddr, 4); | |
52 | ||
53 | if (!is_frag) { | |
54 | if (opt->rr_needaddr) | |
55 | ip_rt_get_source(iph+opt->rr+iph[opt->rr+2]-5, rt); | |
56 | if (opt->ts_needaddr) | |
57 | ip_rt_get_source(iph+opt->ts+iph[opt->ts+2]-9, rt); | |
58 | if (opt->ts_needtime) { | |
59 | struct timeval tv; | |
e25d2ca6 | 60 | __be32 midtime; |
1da177e4 LT |
61 | do_gettimeofday(&tv); |
62 | midtime = htonl((tv.tv_sec % 86400) * 1000 + tv.tv_usec / 1000); | |
63 | memcpy(iph+opt->ts+iph[opt->ts+2]-5, &midtime, 4); | |
64 | } | |
65 | return; | |
66 | } | |
67 | if (opt->rr) { | |
68 | memset(iph+opt->rr, IPOPT_NOP, iph[opt->rr+1]); | |
69 | opt->rr = 0; | |
70 | opt->rr_needaddr = 0; | |
71 | } | |
72 | if (opt->ts) { | |
73 | memset(iph+opt->ts, IPOPT_NOP, iph[opt->ts+1]); | |
74 | opt->ts = 0; | |
75 | opt->ts_needaddr = opt->ts_needtime = 0; | |
76 | } | |
77 | } | |
78 | ||
79 | /* | |
80 | * Provided (sopt, skb) points to received options, | |
81 | * build in dopt compiled option set appropriate for answering. | |
82 | * i.e. invert SRR option, copy anothers, | |
83 | * and grab room in RR/TS options. | |
84 | * | |
85 | * NOTE: dopt cannot point to skb. | |
86 | */ | |
87 | ||
88 | int ip_options_echo(struct ip_options * dopt, struct sk_buff * skb) | |
89 | { | |
90 | struct ip_options *sopt; | |
91 | unsigned char *sptr, *dptr; | |
92 | int soffset, doffset; | |
93 | int optlen; | |
e25d2ca6 | 94 | __be32 daddr; |
1da177e4 LT |
95 | |
96 | memset(dopt, 0, sizeof(struct ip_options)); | |
97 | ||
98 | dopt->is_data = 1; | |
99 | ||
100 | sopt = &(IPCB(skb)->opt); | |
101 | ||
102 | if (sopt->optlen == 0) { | |
103 | dopt->optlen = 0; | |
104 | return 0; | |
105 | } | |
106 | ||
107 | sptr = skb->nh.raw; | |
108 | dptr = dopt->__data; | |
109 | ||
110 | if (skb->dst) | |
111 | daddr = ((struct rtable*)skb->dst)->rt_spec_dst; | |
112 | else | |
113 | daddr = skb->nh.iph->daddr; | |
114 | ||
115 | if (sopt->rr) { | |
116 | optlen = sptr[sopt->rr+1]; | |
117 | soffset = sptr[sopt->rr+2]; | |
118 | dopt->rr = dopt->optlen + sizeof(struct iphdr); | |
119 | memcpy(dptr, sptr+sopt->rr, optlen); | |
120 | if (sopt->rr_needaddr && soffset <= optlen) { | |
121 | if (soffset + 3 > optlen) | |
122 | return -EINVAL; | |
123 | dptr[2] = soffset + 4; | |
124 | dopt->rr_needaddr = 1; | |
125 | } | |
126 | dptr += optlen; | |
127 | dopt->optlen += optlen; | |
128 | } | |
129 | if (sopt->ts) { | |
130 | optlen = sptr[sopt->ts+1]; | |
131 | soffset = sptr[sopt->ts+2]; | |
132 | dopt->ts = dopt->optlen + sizeof(struct iphdr); | |
133 | memcpy(dptr, sptr+sopt->ts, optlen); | |
134 | if (soffset <= optlen) { | |
135 | if (sopt->ts_needaddr) { | |
136 | if (soffset + 3 > optlen) | |
137 | return -EINVAL; | |
138 | dopt->ts_needaddr = 1; | |
139 | soffset += 4; | |
140 | } | |
141 | if (sopt->ts_needtime) { | |
142 | if (soffset + 3 > optlen) | |
143 | return -EINVAL; | |
144 | if ((dptr[3]&0xF) != IPOPT_TS_PRESPEC) { | |
145 | dopt->ts_needtime = 1; | |
146 | soffset += 4; | |
147 | } else { | |
148 | dopt->ts_needtime = 0; | |
149 | ||
150 | if (soffset + 8 <= optlen) { | |
fd683222 | 151 | __be32 addr; |
1da177e4 LT |
152 | |
153 | memcpy(&addr, sptr+soffset-1, 4); | |
154 | if (inet_addr_type(addr) != RTN_LOCAL) { | |
155 | dopt->ts_needtime = 1; | |
156 | soffset += 8; | |
157 | } | |
158 | } | |
159 | } | |
160 | } | |
161 | dptr[2] = soffset; | |
162 | } | |
163 | dptr += optlen; | |
164 | dopt->optlen += optlen; | |
165 | } | |
166 | if (sopt->srr) { | |
167 | unsigned char * start = sptr+sopt->srr; | |
3ca3c68e | 168 | __be32 faddr; |
1da177e4 LT |
169 | |
170 | optlen = start[1]; | |
171 | soffset = start[2]; | |
172 | doffset = 0; | |
173 | if (soffset > optlen) | |
174 | soffset = optlen + 1; | |
175 | soffset -= 4; | |
176 | if (soffset > 3) { | |
177 | memcpy(&faddr, &start[soffset-1], 4); | |
178 | for (soffset-=4, doffset=4; soffset > 3; soffset-=4, doffset+=4) | |
179 | memcpy(&dptr[doffset-1], &start[soffset-1], 4); | |
180 | /* | |
181 | * RFC1812 requires to fix illegal source routes. | |
182 | */ | |
183 | if (memcmp(&skb->nh.iph->saddr, &start[soffset+3], 4) == 0) | |
184 | doffset -= 4; | |
185 | } | |
186 | if (doffset > 3) { | |
187 | memcpy(&start[doffset-1], &daddr, 4); | |
188 | dopt->faddr = faddr; | |
189 | dptr[0] = start[0]; | |
190 | dptr[1] = doffset+3; | |
191 | dptr[2] = 4; | |
192 | dptr += doffset+3; | |
193 | dopt->srr = dopt->optlen + sizeof(struct iphdr); | |
194 | dopt->optlen += doffset+3; | |
195 | dopt->is_strictroute = sopt->is_strictroute; | |
196 | } | |
197 | } | |
11a03f78 PM |
198 | if (sopt->cipso) { |
199 | optlen = sptr[sopt->cipso+1]; | |
200 | dopt->cipso = dopt->optlen+sizeof(struct iphdr); | |
201 | memcpy(dptr, sptr+sopt->cipso, optlen); | |
202 | dptr += optlen; | |
203 | dopt->optlen += optlen; | |
204 | } | |
1da177e4 LT |
205 | while (dopt->optlen & 3) { |
206 | *dptr++ = IPOPT_END; | |
207 | dopt->optlen++; | |
208 | } | |
209 | return 0; | |
210 | } | |
211 | ||
212 | /* | |
213 | * Options "fragmenting", just fill options not | |
214 | * allowed in fragments with NOOPs. | |
215 | * Simple and stupid 8), but the most efficient way. | |
216 | */ | |
217 | ||
218 | void ip_options_fragment(struct sk_buff * skb) | |
219 | { | |
63cbd2fd | 220 | unsigned char * optptr = skb->nh.raw + sizeof(struct iphdr); |
1da177e4 LT |
221 | struct ip_options * opt = &(IPCB(skb)->opt); |
222 | int l = opt->optlen; | |
223 | int optlen; | |
224 | ||
225 | while (l > 0) { | |
226 | switch (*optptr) { | |
227 | case IPOPT_END: | |
228 | return; | |
229 | case IPOPT_NOOP: | |
230 | l--; | |
231 | optptr++; | |
232 | continue; | |
233 | } | |
234 | optlen = optptr[1]; | |
235 | if (optlen<2 || optlen>l) | |
236 | return; | |
237 | if (!IPOPT_COPIED(*optptr)) | |
238 | memset(optptr, IPOPT_NOOP, optlen); | |
239 | l -= optlen; | |
240 | optptr += optlen; | |
241 | } | |
242 | opt->ts = 0; | |
243 | opt->rr = 0; | |
244 | opt->rr_needaddr = 0; | |
245 | opt->ts_needaddr = 0; | |
246 | opt->ts_needtime = 0; | |
247 | return; | |
248 | } | |
249 | ||
250 | /* | |
251 | * Verify options and fill pointers in struct options. | |
252 | * Caller should clear *opt, and set opt->data. | |
253 | * If opt == NULL, then skb->data should point to IP header. | |
254 | */ | |
255 | ||
256 | int ip_options_compile(struct ip_options * opt, struct sk_buff * skb) | |
257 | { | |
258 | int l; | |
259 | unsigned char * iph; | |
260 | unsigned char * optptr; | |
261 | int optlen; | |
262 | unsigned char * pp_ptr = NULL; | |
263 | struct rtable *rt = skb ? (struct rtable*)skb->dst : NULL; | |
264 | ||
265 | if (!opt) { | |
266 | opt = &(IPCB(skb)->opt); | |
1da177e4 LT |
267 | iph = skb->nh.raw; |
268 | opt->optlen = ((struct iphdr *)iph)->ihl*4 - sizeof(struct iphdr); | |
269 | optptr = iph + sizeof(struct iphdr); | |
270 | opt->is_data = 0; | |
271 | } else { | |
272 | optptr = opt->is_data ? opt->__data : (unsigned char*)&(skb->nh.iph[1]); | |
273 | iph = optptr - sizeof(struct iphdr); | |
274 | } | |
275 | ||
276 | for (l = opt->optlen; l > 0; ) { | |
277 | switch (*optptr) { | |
278 | case IPOPT_END: | |
279 | for (optptr++, l--; l>0; optptr++, l--) { | |
280 | if (*optptr != IPOPT_END) { | |
281 | *optptr = IPOPT_END; | |
282 | opt->is_changed = 1; | |
283 | } | |
284 | } | |
285 | goto eol; | |
286 | case IPOPT_NOOP: | |
287 | l--; | |
288 | optptr++; | |
289 | continue; | |
290 | } | |
291 | optlen = optptr[1]; | |
292 | if (optlen<2 || optlen>l) { | |
293 | pp_ptr = optptr; | |
294 | goto error; | |
295 | } | |
296 | switch (*optptr) { | |
297 | case IPOPT_SSRR: | |
298 | case IPOPT_LSRR: | |
299 | if (optlen < 3) { | |
300 | pp_ptr = optptr + 1; | |
301 | goto error; | |
302 | } | |
303 | if (optptr[2] < 4) { | |
304 | pp_ptr = optptr + 2; | |
305 | goto error; | |
306 | } | |
307 | /* NB: cf RFC-1812 5.2.4.1 */ | |
308 | if (opt->srr) { | |
309 | pp_ptr = optptr; | |
310 | goto error; | |
311 | } | |
312 | if (!skb) { | |
313 | if (optptr[2] != 4 || optlen < 7 || ((optlen-3) & 3)) { | |
314 | pp_ptr = optptr + 1; | |
315 | goto error; | |
316 | } | |
317 | memcpy(&opt->faddr, &optptr[3], 4); | |
318 | if (optlen > 7) | |
319 | memmove(&optptr[3], &optptr[7], optlen-7); | |
320 | } | |
321 | opt->is_strictroute = (optptr[0] == IPOPT_SSRR); | |
322 | opt->srr = optptr - iph; | |
323 | break; | |
324 | case IPOPT_RR: | |
325 | if (opt->rr) { | |
326 | pp_ptr = optptr; | |
327 | goto error; | |
328 | } | |
329 | if (optlen < 3) { | |
330 | pp_ptr = optptr + 1; | |
331 | goto error; | |
332 | } | |
333 | if (optptr[2] < 4) { | |
334 | pp_ptr = optptr + 2; | |
335 | goto error; | |
336 | } | |
337 | if (optptr[2] <= optlen) { | |
338 | if (optptr[2]+3 > optlen) { | |
339 | pp_ptr = optptr + 2; | |
340 | goto error; | |
341 | } | |
342 | if (skb) { | |
343 | memcpy(&optptr[optptr[2]-1], &rt->rt_spec_dst, 4); | |
344 | opt->is_changed = 1; | |
345 | } | |
346 | optptr[2] += 4; | |
347 | opt->rr_needaddr = 1; | |
348 | } | |
349 | opt->rr = optptr - iph; | |
350 | break; | |
351 | case IPOPT_TIMESTAMP: | |
352 | if (opt->ts) { | |
353 | pp_ptr = optptr; | |
354 | goto error; | |
355 | } | |
356 | if (optlen < 4) { | |
357 | pp_ptr = optptr + 1; | |
358 | goto error; | |
359 | } | |
360 | if (optptr[2] < 5) { | |
361 | pp_ptr = optptr + 2; | |
362 | goto error; | |
363 | } | |
364 | if (optptr[2] <= optlen) { | |
e25d2ca6 | 365 | __be32 *timeptr = NULL; |
1da177e4 LT |
366 | if (optptr[2]+3 > optptr[1]) { |
367 | pp_ptr = optptr + 2; | |
368 | goto error; | |
369 | } | |
370 | switch (optptr[3]&0xF) { | |
371 | case IPOPT_TS_TSONLY: | |
372 | opt->ts = optptr - iph; | |
373 | if (skb) | |
e25d2ca6 | 374 | timeptr = (__be32*)&optptr[optptr[2]-1]; |
1da177e4 LT |
375 | opt->ts_needtime = 1; |
376 | optptr[2] += 4; | |
377 | break; | |
378 | case IPOPT_TS_TSANDADDR: | |
379 | if (optptr[2]+7 > optptr[1]) { | |
380 | pp_ptr = optptr + 2; | |
381 | goto error; | |
382 | } | |
383 | opt->ts = optptr - iph; | |
384 | if (skb) { | |
385 | memcpy(&optptr[optptr[2]-1], &rt->rt_spec_dst, 4); | |
e25d2ca6 | 386 | timeptr = (__be32*)&optptr[optptr[2]+3]; |
1da177e4 LT |
387 | } |
388 | opt->ts_needaddr = 1; | |
389 | opt->ts_needtime = 1; | |
390 | optptr[2] += 8; | |
391 | break; | |
392 | case IPOPT_TS_PRESPEC: | |
393 | if (optptr[2]+7 > optptr[1]) { | |
394 | pp_ptr = optptr + 2; | |
395 | goto error; | |
396 | } | |
397 | opt->ts = optptr - iph; | |
398 | { | |
fd683222 | 399 | __be32 addr; |
1da177e4 LT |
400 | memcpy(&addr, &optptr[optptr[2]-1], 4); |
401 | if (inet_addr_type(addr) == RTN_UNICAST) | |
402 | break; | |
403 | if (skb) | |
e25d2ca6 | 404 | timeptr = (__be32*)&optptr[optptr[2]+3]; |
1da177e4 LT |
405 | } |
406 | opt->ts_needtime = 1; | |
407 | optptr[2] += 8; | |
408 | break; | |
409 | default: | |
410 | if (!skb && !capable(CAP_NET_RAW)) { | |
411 | pp_ptr = optptr + 3; | |
412 | goto error; | |
413 | } | |
414 | break; | |
415 | } | |
416 | if (timeptr) { | |
417 | struct timeval tv; | |
e25d2ca6 | 418 | __be32 midtime; |
1da177e4 LT |
419 | do_gettimeofday(&tv); |
420 | midtime = htonl((tv.tv_sec % 86400) * 1000 + tv.tv_usec / 1000); | |
e25d2ca6 | 421 | memcpy(timeptr, &midtime, sizeof(__be32)); |
1da177e4 LT |
422 | opt->is_changed = 1; |
423 | } | |
424 | } else { | |
425 | unsigned overflow = optptr[3]>>4; | |
426 | if (overflow == 15) { | |
427 | pp_ptr = optptr + 3; | |
428 | goto error; | |
429 | } | |
430 | opt->ts = optptr - iph; | |
431 | if (skb) { | |
432 | optptr[3] = (optptr[3]&0xF)|((overflow+1)<<4); | |
433 | opt->is_changed = 1; | |
434 | } | |
435 | } | |
436 | break; | |
437 | case IPOPT_RA: | |
438 | if (optlen < 4) { | |
439 | pp_ptr = optptr + 1; | |
440 | goto error; | |
441 | } | |
442 | if (optptr[2] == 0 && optptr[3] == 0) | |
443 | opt->router_alert = optptr - iph; | |
444 | break; | |
11a03f78 | 445 | case IPOPT_CIPSO: |
f8687afe | 446 | if ((!skb && !capable(CAP_NET_RAW)) || opt->cipso) { |
11a03f78 PM |
447 | pp_ptr = optptr; |
448 | goto error; | |
449 | } | |
450 | opt->cipso = optptr - iph; | |
451 | if (cipso_v4_validate(&optptr)) { | |
452 | pp_ptr = optptr; | |
453 | goto error; | |
454 | } | |
455 | break; | |
1da177e4 LT |
456 | case IPOPT_SEC: |
457 | case IPOPT_SID: | |
458 | default: | |
459 | if (!skb && !capable(CAP_NET_RAW)) { | |
460 | pp_ptr = optptr; | |
461 | goto error; | |
462 | } | |
463 | break; | |
464 | } | |
465 | l -= optlen; | |
466 | optptr += optlen; | |
467 | } | |
468 | ||
469 | eol: | |
470 | if (!pp_ptr) | |
471 | return 0; | |
472 | ||
473 | error: | |
474 | if (skb) { | |
475 | icmp_send(skb, ICMP_PARAMETERPROB, 0, htonl((pp_ptr-iph)<<24)); | |
476 | } | |
477 | return -EINVAL; | |
478 | } | |
479 | ||
480 | ||
481 | /* | |
482 | * Undo all the changes done by ip_options_compile(). | |
483 | */ | |
484 | ||
485 | void ip_options_undo(struct ip_options * opt) | |
486 | { | |
487 | if (opt->srr) { | |
488 | unsigned char * optptr = opt->__data+opt->srr-sizeof(struct iphdr); | |
489 | memmove(optptr+7, optptr+3, optptr[1]-7); | |
490 | memcpy(optptr+3, &opt->faddr, 4); | |
491 | } | |
492 | if (opt->rr_needaddr) { | |
493 | unsigned char * optptr = opt->__data+opt->rr-sizeof(struct iphdr); | |
494 | optptr[2] -= 4; | |
495 | memset(&optptr[optptr[2]-1], 0, 4); | |
496 | } | |
497 | if (opt->ts) { | |
498 | unsigned char * optptr = opt->__data+opt->ts-sizeof(struct iphdr); | |
499 | if (opt->ts_needtime) { | |
500 | optptr[2] -= 4; | |
501 | memset(&optptr[optptr[2]-1], 0, 4); | |
502 | if ((optptr[3]&0xF) == IPOPT_TS_PRESPEC) | |
503 | optptr[2] -= 4; | |
504 | } | |
505 | if (opt->ts_needaddr) { | |
506 | optptr[2] -= 4; | |
507 | memset(&optptr[optptr[2]-1], 0, 4); | |
508 | } | |
509 | } | |
510 | } | |
511 | ||
4c6ea29d | 512 | static struct ip_options *ip_options_get_alloc(const int optlen) |
1da177e4 | 513 | { |
4c6ea29d ACM |
514 | struct ip_options *opt = kmalloc(sizeof(*opt) + ((optlen + 3) & ~3), |
515 | GFP_KERNEL); | |
516 | if (opt) | |
517 | memset(opt, 0, sizeof(*opt)); | |
518 | return opt; | |
519 | } | |
1da177e4 | 520 | |
4c6ea29d ACM |
521 | static int ip_options_get_finish(struct ip_options **optp, |
522 | struct ip_options *opt, int optlen) | |
523 | { | |
1da177e4 LT |
524 | while (optlen & 3) |
525 | opt->__data[optlen++] = IPOPT_END; | |
526 | opt->optlen = optlen; | |
527 | opt->is_data = 1; | |
1da177e4 LT |
528 | if (optlen && ip_options_compile(opt, NULL)) { |
529 | kfree(opt); | |
530 | return -EINVAL; | |
531 | } | |
a51482bd | 532 | kfree(*optp); |
1da177e4 LT |
533 | *optp = opt; |
534 | return 0; | |
535 | } | |
536 | ||
4c6ea29d ACM |
537 | int ip_options_get_from_user(struct ip_options **optp, unsigned char __user *data, int optlen) |
538 | { | |
539 | struct ip_options *opt = ip_options_get_alloc(optlen); | |
540 | ||
541 | if (!opt) | |
542 | return -ENOMEM; | |
543 | if (optlen && copy_from_user(opt->__data, data, optlen)) { | |
544 | kfree(opt); | |
545 | return -EFAULT; | |
546 | } | |
547 | return ip_options_get_finish(optp, opt, optlen); | |
548 | } | |
549 | ||
550 | int ip_options_get(struct ip_options **optp, unsigned char *data, int optlen) | |
551 | { | |
552 | struct ip_options *opt = ip_options_get_alloc(optlen); | |
553 | ||
554 | if (!opt) | |
555 | return -ENOMEM; | |
556 | if (optlen) | |
557 | memcpy(opt->__data, data, optlen); | |
558 | return ip_options_get_finish(optp, opt, optlen); | |
559 | } | |
560 | ||
1da177e4 LT |
561 | void ip_forward_options(struct sk_buff *skb) |
562 | { | |
563 | struct ip_options * opt = &(IPCB(skb)->opt); | |
564 | unsigned char * optptr; | |
565 | struct rtable *rt = (struct rtable*)skb->dst; | |
566 | unsigned char *raw = skb->nh.raw; | |
567 | ||
568 | if (opt->rr_needaddr) { | |
569 | optptr = (unsigned char *)raw + opt->rr; | |
570 | ip_rt_get_source(&optptr[optptr[2]-5], rt); | |
571 | opt->is_changed = 1; | |
572 | } | |
573 | if (opt->srr_is_hit) { | |
574 | int srrptr, srrspace; | |
575 | ||
576 | optptr = raw + opt->srr; | |
577 | ||
578 | for ( srrptr=optptr[2], srrspace = optptr[1]; | |
579 | srrptr <= srrspace; | |
580 | srrptr += 4 | |
581 | ) { | |
582 | if (srrptr + 3 > srrspace) | |
583 | break; | |
584 | if (memcmp(&rt->rt_dst, &optptr[srrptr-1], 4) == 0) | |
585 | break; | |
586 | } | |
587 | if (srrptr + 3 <= srrspace) { | |
588 | opt->is_changed = 1; | |
589 | ip_rt_get_source(&optptr[srrptr-1], rt); | |
590 | skb->nh.iph->daddr = rt->rt_dst; | |
591 | optptr[2] = srrptr+4; | |
592 | } else if (net_ratelimit()) | |
593 | printk(KERN_CRIT "ip_forward(): Argh! Destination lost!\n"); | |
594 | if (opt->ts_needaddr) { | |
595 | optptr = raw + opt->ts; | |
596 | ip_rt_get_source(&optptr[optptr[2]-9], rt); | |
597 | opt->is_changed = 1; | |
598 | } | |
599 | } | |
600 | if (opt->is_changed) { | |
601 | opt->is_changed = 0; | |
602 | ip_send_check(skb->nh.iph); | |
603 | } | |
604 | } | |
605 | ||
606 | int ip_options_rcv_srr(struct sk_buff *skb) | |
607 | { | |
608 | struct ip_options *opt = &(IPCB(skb)->opt); | |
609 | int srrspace, srrptr; | |
9e12bb22 | 610 | __be32 nexthop; |
1da177e4 LT |
611 | struct iphdr *iph = skb->nh.iph; |
612 | unsigned char * optptr = skb->nh.raw + opt->srr; | |
613 | struct rtable *rt = (struct rtable*)skb->dst; | |
614 | struct rtable *rt2; | |
615 | int err; | |
616 | ||
617 | if (!opt->srr) | |
618 | return 0; | |
619 | ||
620 | if (skb->pkt_type != PACKET_HOST) | |
621 | return -EINVAL; | |
622 | if (rt->rt_type == RTN_UNICAST) { | |
623 | if (!opt->is_strictroute) | |
624 | return 0; | |
625 | icmp_send(skb, ICMP_PARAMETERPROB, 0, htonl(16<<24)); | |
626 | return -EINVAL; | |
627 | } | |
628 | if (rt->rt_type != RTN_LOCAL) | |
629 | return -EINVAL; | |
630 | ||
631 | for (srrptr=optptr[2], srrspace = optptr[1]; srrptr <= srrspace; srrptr += 4) { | |
632 | if (srrptr + 3 > srrspace) { | |
633 | icmp_send(skb, ICMP_PARAMETERPROB, 0, htonl((opt->srr+2)<<24)); | |
634 | return -EINVAL; | |
635 | } | |
636 | memcpy(&nexthop, &optptr[srrptr-1], 4); | |
637 | ||
638 | rt = (struct rtable*)skb->dst; | |
639 | skb->dst = NULL; | |
640 | err = ip_route_input(skb, nexthop, iph->saddr, iph->tos, skb->dev); | |
641 | rt2 = (struct rtable*)skb->dst; | |
642 | if (err || (rt2->rt_type != RTN_UNICAST && rt2->rt_type != RTN_LOCAL)) { | |
643 | ip_rt_put(rt2); | |
644 | skb->dst = &rt->u.dst; | |
645 | return -EINVAL; | |
646 | } | |
647 | ip_rt_put(rt); | |
648 | if (rt2->rt_type != RTN_LOCAL) | |
649 | break; | |
650 | /* Superfast 8) loopback forward */ | |
651 | memcpy(&iph->daddr, &optptr[srrptr-1], 4); | |
652 | opt->is_changed = 1; | |
653 | } | |
654 | if (srrptr <= srrspace) { | |
655 | opt->srr_is_hit = 1; | |
656 | opt->is_changed = 1; | |
657 | } | |
658 | return 0; | |
659 | } |