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 | * | |
1da177e4 | 8 | * Authors: A.N.Kuznetsov |
e905a9ed | 9 | * |
1da177e4 LT |
10 | */ |
11 | ||
4fc268d2 | 12 | #include <linux/capability.h> |
1da177e4 LT |
13 | #include <linux/module.h> |
14 | #include <linux/types.h> | |
15 | #include <asm/uaccess.h> | |
16 | #include <linux/skbuff.h> | |
17 | #include <linux/ip.h> | |
18 | #include <linux/icmp.h> | |
19 | #include <linux/netdevice.h> | |
20 | #include <linux/rtnetlink.h> | |
21 | #include <net/sock.h> | |
22 | #include <net/ip.h> | |
23 | #include <net/icmp.h> | |
14c85021 | 24 | #include <net/route.h> |
11a03f78 | 25 | #include <net/cipso_ipv4.h> |
1da177e4 | 26 | |
e905a9ed | 27 | /* |
1da177e4 LT |
28 | * Write options to IP header, record destination address to |
29 | * source route option, address of outgoing interface | |
30 | * (we should already know it, so that this function is allowed be | |
31 | * called only after routing decision) and timestamp, | |
32 | * if we originate this datagram. | |
33 | * | |
34 | * daddr is real destination address, next hop is recorded in IP header. | |
35 | * saddr is address of outgoing interface. | |
36 | */ | |
37 | ||
38 | void ip_options_build(struct sk_buff * skb, struct ip_options * opt, | |
8712f774 | 39 | __be32 daddr, struct rtable *rt, int is_frag) |
1da177e4 | 40 | { |
d56f90a7 | 41 | unsigned char *iph = skb_network_header(skb); |
1da177e4 LT |
42 | |
43 | memcpy(&(IPCB(skb)->opt), opt, sizeof(struct ip_options)); | |
44 | memcpy(iph+sizeof(struct iphdr), opt->__data, opt->optlen); | |
45 | opt = &(IPCB(skb)->opt); | |
1da177e4 LT |
46 | |
47 | if (opt->srr) | |
48 | memcpy(iph+opt->srr+iph[opt->srr+1]-4, &daddr, 4); | |
49 | ||
50 | if (!is_frag) { | |
51 | if (opt->rr_needaddr) | |
52 | ip_rt_get_source(iph+opt->rr+iph[opt->rr+2]-5, rt); | |
53 | if (opt->ts_needaddr) | |
54 | ip_rt_get_source(iph+opt->ts+iph[opt->ts+2]-9, rt); | |
55 | if (opt->ts_needtime) { | |
f25c3d61 | 56 | struct timespec tv; |
e25d2ca6 | 57 | __be32 midtime; |
f25c3d61 YH |
58 | getnstimeofday(&tv); |
59 | midtime = htonl((tv.tv_sec % 86400) * MSEC_PER_SEC + tv.tv_nsec / NSEC_PER_MSEC); | |
1da177e4 LT |
60 | memcpy(iph+opt->ts+iph[opt->ts+2]-5, &midtime, 4); |
61 | } | |
62 | return; | |
63 | } | |
64 | if (opt->rr) { | |
65 | memset(iph+opt->rr, IPOPT_NOP, iph[opt->rr+1]); | |
66 | opt->rr = 0; | |
67 | opt->rr_needaddr = 0; | |
68 | } | |
69 | if (opt->ts) { | |
70 | memset(iph+opt->ts, IPOPT_NOP, iph[opt->ts+1]); | |
71 | opt->ts = 0; | |
72 | opt->ts_needaddr = opt->ts_needtime = 0; | |
73 | } | |
74 | } | |
75 | ||
e905a9ed | 76 | /* |
1da177e4 LT |
77 | * Provided (sopt, skb) points to received options, |
78 | * build in dopt compiled option set appropriate for answering. | |
79 | * i.e. invert SRR option, copy anothers, | |
80 | * and grab room in RR/TS options. | |
81 | * | |
82 | * NOTE: dopt cannot point to skb. | |
83 | */ | |
84 | ||
e905a9ed | 85 | int ip_options_echo(struct ip_options * dopt, struct sk_buff * skb) |
1da177e4 LT |
86 | { |
87 | struct ip_options *sopt; | |
88 | unsigned char *sptr, *dptr; | |
89 | int soffset, doffset; | |
90 | int optlen; | |
e25d2ca6 | 91 | __be32 daddr; |
1da177e4 LT |
92 | |
93 | memset(dopt, 0, sizeof(struct ip_options)); | |
94 | ||
1da177e4 LT |
95 | sopt = &(IPCB(skb)->opt); |
96 | ||
97 | if (sopt->optlen == 0) { | |
98 | dopt->optlen = 0; | |
99 | return 0; | |
100 | } | |
101 | ||
d56f90a7 | 102 | sptr = skb_network_header(skb); |
1da177e4 LT |
103 | dptr = dopt->__data; |
104 | ||
ee6b9673 | 105 | daddr = skb->rtable->rt_spec_dst; |
1da177e4 LT |
106 | |
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 | ||
142 | if (soffset + 8 <= optlen) { | |
fd683222 | 143 | __be32 addr; |
1da177e4 LT |
144 | |
145 | memcpy(&addr, sptr+soffset-1, 4); | |
c346dca1 | 146 | if (inet_addr_type(dev_net(skb->dst->dev), addr) != RTN_LOCAL) { |
1da177e4 LT |
147 | 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) { | |
159 | unsigned char * start = sptr+sopt->srr; | |
3ca3c68e | 160 | __be32 faddr; |
1da177e4 LT |
161 | |
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 | */ | |
eddc9ec5 ACM |
175 | if (memcmp(&ip_hdr(skb)->saddr, |
176 | &start[soffset + 3], 4) == 0) | |
1da177e4 LT |
177 | 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 | } | |
11a03f78 PM |
191 | 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 | } | |
1da177e4 LT |
198 | 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 | ||
e905a9ed | 211 | void ip_options_fragment(struct sk_buff * skb) |
1da177e4 | 212 | { |
d56f90a7 | 213 | unsigned char *optptr = skb_network_header(skb) + sizeof(struct iphdr); |
1da177e4 LT |
214 | 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; | |
240 | return; | |
241 | } | |
242 | ||
243 | /* | |
244 | * Verify options and fill pointers in struct options. | |
245 | * Caller should clear *opt, and set opt->data. | |
246 | * If opt == NULL, then skb->data should point to IP header. | |
247 | */ | |
248 | ||
0e6bd4a1 DL |
249 | int ip_options_compile(struct net *net, |
250 | struct ip_options * opt, struct sk_buff * skb) | |
1da177e4 LT |
251 | { |
252 | int l; | |
253 | unsigned char * iph; | |
254 | unsigned char * optptr; | |
255 | int optlen; | |
256 | unsigned char * pp_ptr = NULL; | |
22aba383 | 257 | struct rtable *rt = NULL; |
1da177e4 | 258 | |
22aba383 DL |
259 | if (skb != NULL) { |
260 | rt = skb->rtable; | |
261 | optptr = (unsigned char *)&(ip_hdr(skb)[1]); | |
262 | } else | |
10fe7d85 | 263 | optptr = opt->__data; |
22aba383 | 264 | iph = optptr - sizeof(struct iphdr); |
1da177e4 LT |
265 | |
266 | for (l = opt->optlen; l > 0; ) { | |
267 | switch (*optptr) { | |
268 | case IPOPT_END: | |
269 | for (optptr++, l--; l>0; optptr++, l--) { | |
270 | if (*optptr != IPOPT_END) { | |
271 | *optptr = IPOPT_END; | |
272 | opt->is_changed = 1; | |
273 | } | |
274 | } | |
275 | goto eol; | |
276 | case IPOPT_NOOP: | |
277 | l--; | |
278 | optptr++; | |
279 | continue; | |
280 | } | |
281 | optlen = optptr[1]; | |
282 | if (optlen<2 || optlen>l) { | |
283 | pp_ptr = optptr; | |
284 | goto error; | |
285 | } | |
286 | switch (*optptr) { | |
287 | case IPOPT_SSRR: | |
288 | case IPOPT_LSRR: | |
289 | if (optlen < 3) { | |
290 | pp_ptr = optptr + 1; | |
291 | goto error; | |
292 | } | |
293 | if (optptr[2] < 4) { | |
294 | pp_ptr = optptr + 2; | |
295 | goto error; | |
296 | } | |
297 | /* NB: cf RFC-1812 5.2.4.1 */ | |
298 | if (opt->srr) { | |
299 | pp_ptr = optptr; | |
300 | goto error; | |
301 | } | |
302 | if (!skb) { | |
303 | if (optptr[2] != 4 || optlen < 7 || ((optlen-3) & 3)) { | |
304 | pp_ptr = optptr + 1; | |
305 | goto error; | |
306 | } | |
307 | memcpy(&opt->faddr, &optptr[3], 4); | |
308 | if (optlen > 7) | |
309 | memmove(&optptr[3], &optptr[7], optlen-7); | |
310 | } | |
311 | opt->is_strictroute = (optptr[0] == IPOPT_SSRR); | |
312 | opt->srr = optptr - iph; | |
313 | break; | |
314 | case IPOPT_RR: | |
315 | if (opt->rr) { | |
316 | pp_ptr = optptr; | |
317 | goto error; | |
318 | } | |
319 | if (optlen < 3) { | |
320 | pp_ptr = optptr + 1; | |
321 | goto error; | |
322 | } | |
323 | if (optptr[2] < 4) { | |
324 | pp_ptr = optptr + 2; | |
325 | goto error; | |
326 | } | |
327 | if (optptr[2] <= optlen) { | |
328 | if (optptr[2]+3 > optlen) { | |
329 | pp_ptr = optptr + 2; | |
330 | goto error; | |
331 | } | |
332 | if (skb) { | |
333 | memcpy(&optptr[optptr[2]-1], &rt->rt_spec_dst, 4); | |
334 | opt->is_changed = 1; | |
335 | } | |
336 | optptr[2] += 4; | |
337 | opt->rr_needaddr = 1; | |
338 | } | |
339 | opt->rr = optptr - iph; | |
340 | break; | |
341 | case IPOPT_TIMESTAMP: | |
342 | if (opt->ts) { | |
343 | pp_ptr = optptr; | |
344 | goto error; | |
345 | } | |
346 | if (optlen < 4) { | |
347 | pp_ptr = optptr + 1; | |
348 | goto error; | |
349 | } | |
350 | if (optptr[2] < 5) { | |
351 | pp_ptr = optptr + 2; | |
352 | goto error; | |
353 | } | |
354 | if (optptr[2] <= optlen) { | |
e25d2ca6 | 355 | __be32 *timeptr = NULL; |
1da177e4 LT |
356 | if (optptr[2]+3 > optptr[1]) { |
357 | pp_ptr = optptr + 2; | |
358 | goto error; | |
359 | } | |
360 | switch (optptr[3]&0xF) { | |
361 | case IPOPT_TS_TSONLY: | |
362 | opt->ts = optptr - iph; | |
e905a9ed | 363 | if (skb) |
e25d2ca6 | 364 | timeptr = (__be32*)&optptr[optptr[2]-1]; |
1da177e4 LT |
365 | opt->ts_needtime = 1; |
366 | optptr[2] += 4; | |
367 | break; | |
368 | case IPOPT_TS_TSANDADDR: | |
369 | if (optptr[2]+7 > optptr[1]) { | |
370 | pp_ptr = optptr + 2; | |
371 | goto error; | |
372 | } | |
373 | opt->ts = optptr - iph; | |
374 | if (skb) { | |
375 | memcpy(&optptr[optptr[2]-1], &rt->rt_spec_dst, 4); | |
e25d2ca6 | 376 | timeptr = (__be32*)&optptr[optptr[2]+3]; |
1da177e4 LT |
377 | } |
378 | opt->ts_needaddr = 1; | |
379 | opt->ts_needtime = 1; | |
380 | optptr[2] += 8; | |
381 | break; | |
382 | case IPOPT_TS_PRESPEC: | |
383 | if (optptr[2]+7 > optptr[1]) { | |
384 | pp_ptr = optptr + 2; | |
385 | goto error; | |
386 | } | |
387 | opt->ts = optptr - iph; | |
388 | { | |
fd683222 | 389 | __be32 addr; |
1da177e4 | 390 | memcpy(&addr, &optptr[optptr[2]-1], 4); |
0e6bd4a1 | 391 | if (inet_addr_type(net, addr) == RTN_UNICAST) |
1da177e4 LT |
392 | break; |
393 | if (skb) | |
e25d2ca6 | 394 | timeptr = (__be32*)&optptr[optptr[2]+3]; |
1da177e4 LT |
395 | } |
396 | opt->ts_needtime = 1; | |
397 | optptr[2] += 8; | |
398 | break; | |
399 | default: | |
400 | if (!skb && !capable(CAP_NET_RAW)) { | |
401 | pp_ptr = optptr + 3; | |
402 | goto error; | |
403 | } | |
404 | break; | |
405 | } | |
406 | if (timeptr) { | |
f25c3d61 | 407 | struct timespec tv; |
e25d2ca6 | 408 | __be32 midtime; |
f25c3d61 YH |
409 | getnstimeofday(&tv); |
410 | midtime = htonl((tv.tv_sec % 86400) * MSEC_PER_SEC + tv.tv_nsec / NSEC_PER_MSEC); | |
e25d2ca6 | 411 | memcpy(timeptr, &midtime, sizeof(__be32)); |
1da177e4 LT |
412 | opt->is_changed = 1; |
413 | } | |
414 | } else { | |
415 | unsigned overflow = optptr[3]>>4; | |
416 | if (overflow == 15) { | |
417 | pp_ptr = optptr + 3; | |
418 | goto error; | |
419 | } | |
420 | opt->ts = optptr - iph; | |
421 | if (skb) { | |
422 | optptr[3] = (optptr[3]&0xF)|((overflow+1)<<4); | |
423 | opt->is_changed = 1; | |
424 | } | |
425 | } | |
426 | break; | |
427 | case IPOPT_RA: | |
428 | if (optlen < 4) { | |
429 | pp_ptr = optptr + 1; | |
430 | goto error; | |
431 | } | |
432 | if (optptr[2] == 0 && optptr[3] == 0) | |
433 | opt->router_alert = optptr - iph; | |
434 | break; | |
11a03f78 | 435 | case IPOPT_CIPSO: |
f8687afe | 436 | if ((!skb && !capable(CAP_NET_RAW)) || opt->cipso) { |
11a03f78 PM |
437 | pp_ptr = optptr; |
438 | goto error; | |
439 | } | |
440 | opt->cipso = optptr - iph; | |
15c45f7b | 441 | if (cipso_v4_validate(skb, &optptr)) { |
11a03f78 PM |
442 | pp_ptr = optptr; |
443 | goto error; | |
444 | } | |
445 | break; | |
1da177e4 LT |
446 | case IPOPT_SEC: |
447 | case IPOPT_SID: | |
448 | default: | |
449 | if (!skb && !capable(CAP_NET_RAW)) { | |
450 | pp_ptr = optptr; | |
451 | goto error; | |
452 | } | |
453 | break; | |
454 | } | |
455 | l -= optlen; | |
456 | optptr += optlen; | |
457 | } | |
458 | ||
459 | eol: | |
460 | if (!pp_ptr) | |
461 | return 0; | |
462 | ||
463 | error: | |
464 | if (skb) { | |
465 | icmp_send(skb, ICMP_PARAMETERPROB, 0, htonl((pp_ptr-iph)<<24)); | |
466 | } | |
467 | return -EINVAL; | |
468 | } | |
469 | ||
470 | ||
471 | /* | |
472 | * Undo all the changes done by ip_options_compile(). | |
473 | */ | |
474 | ||
475 | void ip_options_undo(struct ip_options * opt) | |
476 | { | |
477 | if (opt->srr) { | |
478 | unsigned char * optptr = opt->__data+opt->srr-sizeof(struct iphdr); | |
479 | memmove(optptr+7, optptr+3, optptr[1]-7); | |
480 | memcpy(optptr+3, &opt->faddr, 4); | |
481 | } | |
482 | if (opt->rr_needaddr) { | |
483 | unsigned char * optptr = opt->__data+opt->rr-sizeof(struct iphdr); | |
484 | optptr[2] -= 4; | |
485 | memset(&optptr[optptr[2]-1], 0, 4); | |
486 | } | |
487 | if (opt->ts) { | |
488 | unsigned char * optptr = opt->__data+opt->ts-sizeof(struct iphdr); | |
489 | if (opt->ts_needtime) { | |
490 | optptr[2] -= 4; | |
491 | memset(&optptr[optptr[2]-1], 0, 4); | |
492 | if ((optptr[3]&0xF) == IPOPT_TS_PRESPEC) | |
493 | optptr[2] -= 4; | |
494 | } | |
495 | if (opt->ts_needaddr) { | |
496 | optptr[2] -= 4; | |
497 | memset(&optptr[optptr[2]-1], 0, 4); | |
498 | } | |
499 | } | |
500 | } | |
501 | ||
4c6ea29d | 502 | static struct ip_options *ip_options_get_alloc(const int optlen) |
1da177e4 | 503 | { |
37640703 MK |
504 | return kzalloc(sizeof(struct ip_options) + ((optlen + 3) & ~3), |
505 | GFP_KERNEL); | |
4c6ea29d | 506 | } |
1da177e4 | 507 | |
f2c4802b | 508 | static int ip_options_get_finish(struct net *net, struct ip_options **optp, |
4c6ea29d ACM |
509 | struct ip_options *opt, int optlen) |
510 | { | |
1da177e4 LT |
511 | while (optlen & 3) |
512 | opt->__data[optlen++] = IPOPT_END; | |
513 | opt->optlen = optlen; | |
f2c4802b | 514 | if (optlen && ip_options_compile(net, opt, NULL)) { |
1da177e4 LT |
515 | kfree(opt); |
516 | return -EINVAL; | |
517 | } | |
a51482bd | 518 | kfree(*optp); |
1da177e4 LT |
519 | *optp = opt; |
520 | return 0; | |
521 | } | |
522 | ||
f2c4802b DL |
523 | int ip_options_get_from_user(struct net *net, struct ip_options **optp, |
524 | unsigned char __user *data, int optlen) | |
4c6ea29d ACM |
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 | } | |
f2c4802b | 534 | return ip_options_get_finish(net, optp, opt, optlen); |
4c6ea29d ACM |
535 | } |
536 | ||
f2c4802b DL |
537 | int ip_options_get(struct net *net, struct ip_options **optp, |
538 | unsigned char *data, int optlen) | |
4c6ea29d ACM |
539 | { |
540 | struct ip_options *opt = ip_options_get_alloc(optlen); | |
541 | ||
542 | if (!opt) | |
543 | return -ENOMEM; | |
544 | if (optlen) | |
545 | memcpy(opt->__data, data, optlen); | |
f2c4802b | 546 | return ip_options_get_finish(net, optp, opt, optlen); |
4c6ea29d ACM |
547 | } |
548 | ||
1da177e4 LT |
549 | void ip_forward_options(struct sk_buff *skb) |
550 | { | |
551 | struct ip_options * opt = &(IPCB(skb)->opt); | |
552 | unsigned char * optptr; | |
ee6b9673 | 553 | struct rtable *rt = skb->rtable; |
d56f90a7 | 554 | unsigned char *raw = skb_network_header(skb); |
1da177e4 LT |
555 | |
556 | if (opt->rr_needaddr) { | |
557 | optptr = (unsigned char *)raw + opt->rr; | |
558 | ip_rt_get_source(&optptr[optptr[2]-5], rt); | |
559 | opt->is_changed = 1; | |
560 | } | |
561 | if (opt->srr_is_hit) { | |
562 | int srrptr, srrspace; | |
563 | ||
564 | optptr = raw + opt->srr; | |
565 | ||
566 | for ( srrptr=optptr[2], srrspace = optptr[1]; | |
567 | srrptr <= srrspace; | |
568 | srrptr += 4 | |
569 | ) { | |
570 | if (srrptr + 3 > srrspace) | |
571 | break; | |
572 | if (memcmp(&rt->rt_dst, &optptr[srrptr-1], 4) == 0) | |
573 | break; | |
574 | } | |
575 | if (srrptr + 3 <= srrspace) { | |
576 | opt->is_changed = 1; | |
577 | ip_rt_get_source(&optptr[srrptr-1], rt); | |
eddc9ec5 | 578 | ip_hdr(skb)->daddr = rt->rt_dst; |
1da177e4 LT |
579 | optptr[2] = srrptr+4; |
580 | } else if (net_ratelimit()) | |
581 | printk(KERN_CRIT "ip_forward(): Argh! Destination lost!\n"); | |
582 | if (opt->ts_needaddr) { | |
583 | optptr = raw + opt->ts; | |
584 | ip_rt_get_source(&optptr[optptr[2]-9], rt); | |
585 | opt->is_changed = 1; | |
586 | } | |
587 | } | |
588 | if (opt->is_changed) { | |
589 | opt->is_changed = 0; | |
eddc9ec5 | 590 | ip_send_check(ip_hdr(skb)); |
1da177e4 LT |
591 | } |
592 | } | |
593 | ||
594 | int ip_options_rcv_srr(struct sk_buff *skb) | |
595 | { | |
596 | struct ip_options *opt = &(IPCB(skb)->opt); | |
597 | int srrspace, srrptr; | |
9e12bb22 | 598 | __be32 nexthop; |
eddc9ec5 | 599 | struct iphdr *iph = ip_hdr(skb); |
d56f90a7 | 600 | unsigned char *optptr = skb_network_header(skb) + opt->srr; |
ee6b9673 | 601 | struct rtable *rt = skb->rtable; |
1da177e4 LT |
602 | struct rtable *rt2; |
603 | int err; | |
604 | ||
605 | if (!opt->srr) | |
606 | return 0; | |
607 | ||
608 | if (skb->pkt_type != PACKET_HOST) | |
609 | return -EINVAL; | |
610 | if (rt->rt_type == RTN_UNICAST) { | |
611 | if (!opt->is_strictroute) | |
612 | return 0; | |
613 | icmp_send(skb, ICMP_PARAMETERPROB, 0, htonl(16<<24)); | |
614 | return -EINVAL; | |
615 | } | |
616 | if (rt->rt_type != RTN_LOCAL) | |
617 | return -EINVAL; | |
618 | ||
619 | for (srrptr=optptr[2], srrspace = optptr[1]; srrptr <= srrspace; srrptr += 4) { | |
620 | if (srrptr + 3 > srrspace) { | |
621 | icmp_send(skb, ICMP_PARAMETERPROB, 0, htonl((opt->srr+2)<<24)); | |
622 | return -EINVAL; | |
623 | } | |
624 | memcpy(&nexthop, &optptr[srrptr-1], 4); | |
625 | ||
ee6b9673 ED |
626 | rt = skb->rtable; |
627 | skb->rtable = NULL; | |
1da177e4 | 628 | err = ip_route_input(skb, nexthop, iph->saddr, iph->tos, skb->dev); |
ee6b9673 | 629 | rt2 = skb->rtable; |
1da177e4 LT |
630 | if (err || (rt2->rt_type != RTN_UNICAST && rt2->rt_type != RTN_LOCAL)) { |
631 | ip_rt_put(rt2); | |
ee6b9673 | 632 | skb->rtable = rt; |
1da177e4 LT |
633 | return -EINVAL; |
634 | } | |
635 | ip_rt_put(rt); | |
636 | if (rt2->rt_type != RTN_LOCAL) | |
637 | break; | |
638 | /* Superfast 8) loopback forward */ | |
639 | memcpy(&iph->daddr, &optptr[srrptr-1], 4); | |
640 | opt->is_changed = 1; | |
641 | } | |
642 | if (srrptr <= srrspace) { | |
643 | opt->srr_is_hit = 1; | |
644 | opt->is_changed = 1; | |
645 | } | |
646 | return 0; | |
647 | } |