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Commit | Line | Data |
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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); | |
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 | ||
e905a9ed | 79 | /* |
1da177e4 LT |
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 | ||
e905a9ed | 88 | int ip_options_echo(struct ip_options * dopt, struct sk_buff * skb) |
1da177e4 LT |
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 | ||
d56f90a7 | 107 | sptr = skb_network_header(skb); |
1da177e4 LT |
108 | dptr = dopt->__data; |
109 | ||
ee6b9673 | 110 | daddr = skb->rtable->rt_spec_dst; |
1da177e4 LT |
111 | |
112 | if (sopt->rr) { | |
113 | optlen = sptr[sopt->rr+1]; | |
114 | soffset = sptr[sopt->rr+2]; | |
115 | dopt->rr = dopt->optlen + sizeof(struct iphdr); | |
116 | memcpy(dptr, sptr+sopt->rr, optlen); | |
117 | if (sopt->rr_needaddr && soffset <= optlen) { | |
118 | if (soffset + 3 > optlen) | |
119 | return -EINVAL; | |
120 | dptr[2] = soffset + 4; | |
121 | dopt->rr_needaddr = 1; | |
122 | } | |
123 | dptr += optlen; | |
124 | dopt->optlen += optlen; | |
125 | } | |
126 | if (sopt->ts) { | |
127 | optlen = sptr[sopt->ts+1]; | |
128 | soffset = sptr[sopt->ts+2]; | |
129 | dopt->ts = dopt->optlen + sizeof(struct iphdr); | |
130 | memcpy(dptr, sptr+sopt->ts, optlen); | |
131 | if (soffset <= optlen) { | |
132 | if (sopt->ts_needaddr) { | |
133 | if (soffset + 3 > optlen) | |
134 | return -EINVAL; | |
135 | dopt->ts_needaddr = 1; | |
136 | soffset += 4; | |
137 | } | |
138 | if (sopt->ts_needtime) { | |
139 | if (soffset + 3 > optlen) | |
140 | return -EINVAL; | |
141 | if ((dptr[3]&0xF) != IPOPT_TS_PRESPEC) { | |
142 | dopt->ts_needtime = 1; | |
143 | soffset += 4; | |
144 | } else { | |
145 | dopt->ts_needtime = 0; | |
146 | ||
147 | if (soffset + 8 <= optlen) { | |
fd683222 | 148 | __be32 addr; |
1da177e4 LT |
149 | |
150 | memcpy(&addr, sptr+soffset-1, 4); | |
6b175b26 | 151 | if (inet_addr_type(&init_net, addr) != RTN_LOCAL) { |
1da177e4 LT |
152 | dopt->ts_needtime = 1; |
153 | soffset += 8; | |
154 | } | |
155 | } | |
156 | } | |
157 | } | |
158 | dptr[2] = soffset; | |
159 | } | |
160 | dptr += optlen; | |
161 | dopt->optlen += optlen; | |
162 | } | |
163 | if (sopt->srr) { | |
164 | unsigned char * start = sptr+sopt->srr; | |
3ca3c68e | 165 | __be32 faddr; |
1da177e4 LT |
166 | |
167 | optlen = start[1]; | |
168 | soffset = start[2]; | |
169 | doffset = 0; | |
170 | if (soffset > optlen) | |
171 | soffset = optlen + 1; | |
172 | soffset -= 4; | |
173 | if (soffset > 3) { | |
174 | memcpy(&faddr, &start[soffset-1], 4); | |
175 | for (soffset-=4, doffset=4; soffset > 3; soffset-=4, doffset+=4) | |
176 | memcpy(&dptr[doffset-1], &start[soffset-1], 4); | |
177 | /* | |
178 | * RFC1812 requires to fix illegal source routes. | |
179 | */ | |
eddc9ec5 ACM |
180 | if (memcmp(&ip_hdr(skb)->saddr, |
181 | &start[soffset + 3], 4) == 0) | |
1da177e4 LT |
182 | doffset -= 4; |
183 | } | |
184 | if (doffset > 3) { | |
185 | memcpy(&start[doffset-1], &daddr, 4); | |
186 | dopt->faddr = faddr; | |
187 | dptr[0] = start[0]; | |
188 | dptr[1] = doffset+3; | |
189 | dptr[2] = 4; | |
190 | dptr += doffset+3; | |
191 | dopt->srr = dopt->optlen + sizeof(struct iphdr); | |
192 | dopt->optlen += doffset+3; | |
193 | dopt->is_strictroute = sopt->is_strictroute; | |
194 | } | |
195 | } | |
11a03f78 PM |
196 | if (sopt->cipso) { |
197 | optlen = sptr[sopt->cipso+1]; | |
198 | dopt->cipso = dopt->optlen+sizeof(struct iphdr); | |
199 | memcpy(dptr, sptr+sopt->cipso, optlen); | |
200 | dptr += optlen; | |
201 | dopt->optlen += optlen; | |
202 | } | |
1da177e4 LT |
203 | while (dopt->optlen & 3) { |
204 | *dptr++ = IPOPT_END; | |
205 | dopt->optlen++; | |
206 | } | |
207 | return 0; | |
208 | } | |
209 | ||
210 | /* | |
211 | * Options "fragmenting", just fill options not | |
212 | * allowed in fragments with NOOPs. | |
213 | * Simple and stupid 8), but the most efficient way. | |
214 | */ | |
215 | ||
e905a9ed | 216 | void ip_options_fragment(struct sk_buff * skb) |
1da177e4 | 217 | { |
d56f90a7 | 218 | unsigned char *optptr = skb_network_header(skb) + sizeof(struct iphdr); |
1da177e4 LT |
219 | struct ip_options * opt = &(IPCB(skb)->opt); |
220 | int l = opt->optlen; | |
221 | int optlen; | |
222 | ||
223 | while (l > 0) { | |
224 | switch (*optptr) { | |
225 | case IPOPT_END: | |
226 | return; | |
227 | case IPOPT_NOOP: | |
228 | l--; | |
229 | optptr++; | |
230 | continue; | |
231 | } | |
232 | optlen = optptr[1]; | |
233 | if (optlen<2 || optlen>l) | |
234 | return; | |
235 | if (!IPOPT_COPIED(*optptr)) | |
236 | memset(optptr, IPOPT_NOOP, optlen); | |
237 | l -= optlen; | |
238 | optptr += optlen; | |
239 | } | |
240 | opt->ts = 0; | |
241 | opt->rr = 0; | |
242 | opt->rr_needaddr = 0; | |
243 | opt->ts_needaddr = 0; | |
244 | opt->ts_needtime = 0; | |
245 | return; | |
246 | } | |
247 | ||
248 | /* | |
249 | * Verify options and fill pointers in struct options. | |
250 | * Caller should clear *opt, and set opt->data. | |
251 | * If opt == NULL, then skb->data should point to IP header. | |
252 | */ | |
253 | ||
254 | int ip_options_compile(struct ip_options * opt, struct sk_buff * skb) | |
255 | { | |
256 | int l; | |
257 | unsigned char * iph; | |
258 | unsigned char * optptr; | |
259 | int optlen; | |
260 | unsigned char * pp_ptr = NULL; | |
ee6b9673 | 261 | struct rtable *rt = skb ? skb->rtable : NULL; |
1da177e4 LT |
262 | |
263 | if (!opt) { | |
264 | opt = &(IPCB(skb)->opt); | |
d56f90a7 | 265 | iph = skb_network_header(skb); |
1da177e4 LT |
266 | opt->optlen = ((struct iphdr *)iph)->ihl*4 - sizeof(struct iphdr); |
267 | optptr = iph + sizeof(struct iphdr); | |
268 | opt->is_data = 0; | |
269 | } else { | |
eddc9ec5 ACM |
270 | optptr = opt->is_data ? opt->__data : |
271 | (unsigned char *)&(ip_hdr(skb)[1]); | |
1da177e4 LT |
272 | iph = optptr - sizeof(struct iphdr); |
273 | } | |
274 | ||
275 | for (l = opt->optlen; l > 0; ) { | |
276 | switch (*optptr) { | |
277 | case IPOPT_END: | |
278 | for (optptr++, l--; l>0; optptr++, l--) { | |
279 | if (*optptr != IPOPT_END) { | |
280 | *optptr = IPOPT_END; | |
281 | opt->is_changed = 1; | |
282 | } | |
283 | } | |
284 | goto eol; | |
285 | case IPOPT_NOOP: | |
286 | l--; | |
287 | optptr++; | |
288 | continue; | |
289 | } | |
290 | optlen = optptr[1]; | |
291 | if (optlen<2 || optlen>l) { | |
292 | pp_ptr = optptr; | |
293 | goto error; | |
294 | } | |
295 | switch (*optptr) { | |
296 | case IPOPT_SSRR: | |
297 | case IPOPT_LSRR: | |
298 | if (optlen < 3) { | |
299 | pp_ptr = optptr + 1; | |
300 | goto error; | |
301 | } | |
302 | if (optptr[2] < 4) { | |
303 | pp_ptr = optptr + 2; | |
304 | goto error; | |
305 | } | |
306 | /* NB: cf RFC-1812 5.2.4.1 */ | |
307 | if (opt->srr) { | |
308 | pp_ptr = optptr; | |
309 | goto error; | |
310 | } | |
311 | if (!skb) { | |
312 | if (optptr[2] != 4 || optlen < 7 || ((optlen-3) & 3)) { | |
313 | pp_ptr = optptr + 1; | |
314 | goto error; | |
315 | } | |
316 | memcpy(&opt->faddr, &optptr[3], 4); | |
317 | if (optlen > 7) | |
318 | memmove(&optptr[3], &optptr[7], optlen-7); | |
319 | } | |
320 | opt->is_strictroute = (optptr[0] == IPOPT_SSRR); | |
321 | opt->srr = optptr - iph; | |
322 | break; | |
323 | case IPOPT_RR: | |
324 | if (opt->rr) { | |
325 | pp_ptr = optptr; | |
326 | goto error; | |
327 | } | |
328 | if (optlen < 3) { | |
329 | pp_ptr = optptr + 1; | |
330 | goto error; | |
331 | } | |
332 | if (optptr[2] < 4) { | |
333 | pp_ptr = optptr + 2; | |
334 | goto error; | |
335 | } | |
336 | if (optptr[2] <= optlen) { | |
337 | if (optptr[2]+3 > optlen) { | |
338 | pp_ptr = optptr + 2; | |
339 | goto error; | |
340 | } | |
341 | if (skb) { | |
342 | memcpy(&optptr[optptr[2]-1], &rt->rt_spec_dst, 4); | |
343 | opt->is_changed = 1; | |
344 | } | |
345 | optptr[2] += 4; | |
346 | opt->rr_needaddr = 1; | |
347 | } | |
348 | opt->rr = optptr - iph; | |
349 | break; | |
350 | case IPOPT_TIMESTAMP: | |
351 | if (opt->ts) { | |
352 | pp_ptr = optptr; | |
353 | goto error; | |
354 | } | |
355 | if (optlen < 4) { | |
356 | pp_ptr = optptr + 1; | |
357 | goto error; | |
358 | } | |
359 | if (optptr[2] < 5) { | |
360 | pp_ptr = optptr + 2; | |
361 | goto error; | |
362 | } | |
363 | if (optptr[2] <= optlen) { | |
e25d2ca6 | 364 | __be32 *timeptr = NULL; |
1da177e4 LT |
365 | if (optptr[2]+3 > optptr[1]) { |
366 | pp_ptr = optptr + 2; | |
367 | goto error; | |
368 | } | |
369 | switch (optptr[3]&0xF) { | |
370 | case IPOPT_TS_TSONLY: | |
371 | opt->ts = optptr - iph; | |
e905a9ed | 372 | if (skb) |
e25d2ca6 | 373 | timeptr = (__be32*)&optptr[optptr[2]-1]; |
1da177e4 LT |
374 | opt->ts_needtime = 1; |
375 | optptr[2] += 4; | |
376 | break; | |
377 | case IPOPT_TS_TSANDADDR: | |
378 | if (optptr[2]+7 > optptr[1]) { | |
379 | pp_ptr = optptr + 2; | |
380 | goto error; | |
381 | } | |
382 | opt->ts = optptr - iph; | |
383 | if (skb) { | |
384 | memcpy(&optptr[optptr[2]-1], &rt->rt_spec_dst, 4); | |
e25d2ca6 | 385 | timeptr = (__be32*)&optptr[optptr[2]+3]; |
1da177e4 LT |
386 | } |
387 | opt->ts_needaddr = 1; | |
388 | opt->ts_needtime = 1; | |
389 | optptr[2] += 8; | |
390 | break; | |
391 | case IPOPT_TS_PRESPEC: | |
392 | if (optptr[2]+7 > optptr[1]) { | |
393 | pp_ptr = optptr + 2; | |
394 | goto error; | |
395 | } | |
396 | opt->ts = optptr - iph; | |
397 | { | |
fd683222 | 398 | __be32 addr; |
1da177e4 | 399 | memcpy(&addr, &optptr[optptr[2]-1], 4); |
6b175b26 | 400 | if (inet_addr_type(&init_net, addr) == RTN_UNICAST) |
1da177e4 LT |
401 | break; |
402 | if (skb) | |
e25d2ca6 | 403 | timeptr = (__be32*)&optptr[optptr[2]+3]; |
1da177e4 LT |
404 | } |
405 | opt->ts_needtime = 1; | |
406 | optptr[2] += 8; | |
407 | break; | |
408 | default: | |
409 | if (!skb && !capable(CAP_NET_RAW)) { | |
410 | pp_ptr = optptr + 3; | |
411 | goto error; | |
412 | } | |
413 | break; | |
414 | } | |
415 | if (timeptr) { | |
416 | struct timeval tv; | |
e25d2ca6 | 417 | __be32 midtime; |
1da177e4 LT |
418 | do_gettimeofday(&tv); |
419 | midtime = htonl((tv.tv_sec % 86400) * 1000 + tv.tv_usec / 1000); | |
e25d2ca6 | 420 | memcpy(timeptr, &midtime, sizeof(__be32)); |
1da177e4 LT |
421 | opt->is_changed = 1; |
422 | } | |
423 | } else { | |
424 | unsigned overflow = optptr[3]>>4; | |
425 | if (overflow == 15) { | |
426 | pp_ptr = optptr + 3; | |
427 | goto error; | |
428 | } | |
429 | opt->ts = optptr - iph; | |
430 | if (skb) { | |
431 | optptr[3] = (optptr[3]&0xF)|((overflow+1)<<4); | |
432 | opt->is_changed = 1; | |
433 | } | |
434 | } | |
435 | break; | |
436 | case IPOPT_RA: | |
437 | if (optlen < 4) { | |
438 | pp_ptr = optptr + 1; | |
439 | goto error; | |
440 | } | |
441 | if (optptr[2] == 0 && optptr[3] == 0) | |
442 | opt->router_alert = optptr - iph; | |
443 | break; | |
11a03f78 | 444 | case IPOPT_CIPSO: |
f8687afe | 445 | if ((!skb && !capable(CAP_NET_RAW)) || opt->cipso) { |
11a03f78 PM |
446 | pp_ptr = optptr; |
447 | goto error; | |
448 | } | |
449 | opt->cipso = optptr - iph; | |
e905a9ed | 450 | if (cipso_v4_validate(&optptr)) { |
11a03f78 PM |
451 | pp_ptr = optptr; |
452 | goto error; | |
453 | } | |
454 | break; | |
1da177e4 LT |
455 | case IPOPT_SEC: |
456 | case IPOPT_SID: | |
457 | default: | |
458 | if (!skb && !capable(CAP_NET_RAW)) { | |
459 | pp_ptr = optptr; | |
460 | goto error; | |
461 | } | |
462 | break; | |
463 | } | |
464 | l -= optlen; | |
465 | optptr += optlen; | |
466 | } | |
467 | ||
468 | eol: | |
469 | if (!pp_ptr) | |
470 | return 0; | |
471 | ||
472 | error: | |
473 | if (skb) { | |
474 | icmp_send(skb, ICMP_PARAMETERPROB, 0, htonl((pp_ptr-iph)<<24)); | |
475 | } | |
476 | return -EINVAL; | |
477 | } | |
478 | ||
479 | ||
480 | /* | |
481 | * Undo all the changes done by ip_options_compile(). | |
482 | */ | |
483 | ||
484 | void ip_options_undo(struct ip_options * opt) | |
485 | { | |
486 | if (opt->srr) { | |
487 | unsigned char * optptr = opt->__data+opt->srr-sizeof(struct iphdr); | |
488 | memmove(optptr+7, optptr+3, optptr[1]-7); | |
489 | memcpy(optptr+3, &opt->faddr, 4); | |
490 | } | |
491 | if (opt->rr_needaddr) { | |
492 | unsigned char * optptr = opt->__data+opt->rr-sizeof(struct iphdr); | |
493 | optptr[2] -= 4; | |
494 | memset(&optptr[optptr[2]-1], 0, 4); | |
495 | } | |
496 | if (opt->ts) { | |
497 | unsigned char * optptr = opt->__data+opt->ts-sizeof(struct iphdr); | |
498 | if (opt->ts_needtime) { | |
499 | optptr[2] -= 4; | |
500 | memset(&optptr[optptr[2]-1], 0, 4); | |
501 | if ((optptr[3]&0xF) == IPOPT_TS_PRESPEC) | |
502 | optptr[2] -= 4; | |
503 | } | |
504 | if (opt->ts_needaddr) { | |
505 | optptr[2] -= 4; | |
506 | memset(&optptr[optptr[2]-1], 0, 4); | |
507 | } | |
508 | } | |
509 | } | |
510 | ||
4c6ea29d | 511 | static struct ip_options *ip_options_get_alloc(const int optlen) |
1da177e4 | 512 | { |
37640703 MK |
513 | return kzalloc(sizeof(struct ip_options) + ((optlen + 3) & ~3), |
514 | GFP_KERNEL); | |
4c6ea29d | 515 | } |
1da177e4 | 516 | |
4c6ea29d ACM |
517 | static int ip_options_get_finish(struct ip_options **optp, |
518 | struct ip_options *opt, int optlen) | |
519 | { | |
1da177e4 LT |
520 | while (optlen & 3) |
521 | opt->__data[optlen++] = IPOPT_END; | |
522 | opt->optlen = optlen; | |
523 | opt->is_data = 1; | |
1da177e4 LT |
524 | if (optlen && ip_options_compile(opt, NULL)) { |
525 | kfree(opt); | |
526 | return -EINVAL; | |
527 | } | |
a51482bd | 528 | kfree(*optp); |
1da177e4 LT |
529 | *optp = opt; |
530 | return 0; | |
531 | } | |
532 | ||
4c6ea29d ACM |
533 | int ip_options_get_from_user(struct ip_options **optp, unsigned char __user *data, int optlen) |
534 | { | |
535 | struct ip_options *opt = ip_options_get_alloc(optlen); | |
536 | ||
537 | if (!opt) | |
538 | return -ENOMEM; | |
539 | if (optlen && copy_from_user(opt->__data, data, optlen)) { | |
540 | kfree(opt); | |
541 | return -EFAULT; | |
542 | } | |
543 | return ip_options_get_finish(optp, opt, optlen); | |
544 | } | |
545 | ||
546 | int ip_options_get(struct ip_options **optp, unsigned char *data, int optlen) | |
547 | { | |
548 | struct ip_options *opt = ip_options_get_alloc(optlen); | |
549 | ||
550 | if (!opt) | |
551 | return -ENOMEM; | |
552 | if (optlen) | |
553 | memcpy(opt->__data, data, optlen); | |
554 | return ip_options_get_finish(optp, opt, optlen); | |
555 | } | |
556 | ||
1da177e4 LT |
557 | void ip_forward_options(struct sk_buff *skb) |
558 | { | |
559 | struct ip_options * opt = &(IPCB(skb)->opt); | |
560 | unsigned char * optptr; | |
ee6b9673 | 561 | struct rtable *rt = skb->rtable; |
d56f90a7 | 562 | unsigned char *raw = skb_network_header(skb); |
1da177e4 LT |
563 | |
564 | if (opt->rr_needaddr) { | |
565 | optptr = (unsigned char *)raw + opt->rr; | |
566 | ip_rt_get_source(&optptr[optptr[2]-5], rt); | |
567 | opt->is_changed = 1; | |
568 | } | |
569 | if (opt->srr_is_hit) { | |
570 | int srrptr, srrspace; | |
571 | ||
572 | optptr = raw + opt->srr; | |
573 | ||
574 | for ( srrptr=optptr[2], srrspace = optptr[1]; | |
575 | srrptr <= srrspace; | |
576 | srrptr += 4 | |
577 | ) { | |
578 | if (srrptr + 3 > srrspace) | |
579 | break; | |
580 | if (memcmp(&rt->rt_dst, &optptr[srrptr-1], 4) == 0) | |
581 | break; | |
582 | } | |
583 | if (srrptr + 3 <= srrspace) { | |
584 | opt->is_changed = 1; | |
585 | ip_rt_get_source(&optptr[srrptr-1], rt); | |
eddc9ec5 | 586 | ip_hdr(skb)->daddr = rt->rt_dst; |
1da177e4 LT |
587 | optptr[2] = srrptr+4; |
588 | } else if (net_ratelimit()) | |
589 | printk(KERN_CRIT "ip_forward(): Argh! Destination lost!\n"); | |
590 | if (opt->ts_needaddr) { | |
591 | optptr = raw + opt->ts; | |
592 | ip_rt_get_source(&optptr[optptr[2]-9], rt); | |
593 | opt->is_changed = 1; | |
594 | } | |
595 | } | |
596 | if (opt->is_changed) { | |
597 | opt->is_changed = 0; | |
eddc9ec5 | 598 | ip_send_check(ip_hdr(skb)); |
1da177e4 LT |
599 | } |
600 | } | |
601 | ||
602 | int ip_options_rcv_srr(struct sk_buff *skb) | |
603 | { | |
604 | struct ip_options *opt = &(IPCB(skb)->opt); | |
605 | int srrspace, srrptr; | |
9e12bb22 | 606 | __be32 nexthop; |
eddc9ec5 | 607 | struct iphdr *iph = ip_hdr(skb); |
d56f90a7 | 608 | unsigned char *optptr = skb_network_header(skb) + opt->srr; |
ee6b9673 | 609 | struct rtable *rt = skb->rtable; |
1da177e4 LT |
610 | struct rtable *rt2; |
611 | int err; | |
612 | ||
613 | if (!opt->srr) | |
614 | return 0; | |
615 | ||
616 | if (skb->pkt_type != PACKET_HOST) | |
617 | return -EINVAL; | |
618 | if (rt->rt_type == RTN_UNICAST) { | |
619 | if (!opt->is_strictroute) | |
620 | return 0; | |
621 | icmp_send(skb, ICMP_PARAMETERPROB, 0, htonl(16<<24)); | |
622 | return -EINVAL; | |
623 | } | |
624 | if (rt->rt_type != RTN_LOCAL) | |
625 | return -EINVAL; | |
626 | ||
627 | for (srrptr=optptr[2], srrspace = optptr[1]; srrptr <= srrspace; srrptr += 4) { | |
628 | if (srrptr + 3 > srrspace) { | |
629 | icmp_send(skb, ICMP_PARAMETERPROB, 0, htonl((opt->srr+2)<<24)); | |
630 | return -EINVAL; | |
631 | } | |
632 | memcpy(&nexthop, &optptr[srrptr-1], 4); | |
633 | ||
ee6b9673 ED |
634 | rt = skb->rtable; |
635 | skb->rtable = NULL; | |
1da177e4 | 636 | err = ip_route_input(skb, nexthop, iph->saddr, iph->tos, skb->dev); |
ee6b9673 | 637 | rt2 = skb->rtable; |
1da177e4 LT |
638 | if (err || (rt2->rt_type != RTN_UNICAST && rt2->rt_type != RTN_LOCAL)) { |
639 | ip_rt_put(rt2); | |
ee6b9673 | 640 | skb->rtable = rt; |
1da177e4 LT |
641 | return -EINVAL; |
642 | } | |
643 | ip_rt_put(rt); | |
644 | if (rt2->rt_type != RTN_LOCAL) | |
645 | break; | |
646 | /* Superfast 8) loopback forward */ | |
647 | memcpy(&iph->daddr, &optptr[srrptr-1], 4); | |
648 | opt->is_changed = 1; | |
649 | } | |
650 | if (srrptr <= srrspace) { | |
651 | opt->srr_is_hit = 1; | |
652 | opt->is_changed = 1; | |
653 | } | |
654 | return 0; | |
655 | } |