1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * INET An implementation of the TCP/IP protocol suite for the LINUX |
4 | * operating system. INET is implemented using the BSD Socket |
5 | * interface as the means of communication with the user level. |
6 | * |
7 | * The options processing module for ip.c |
8 | * |
9 | * Authors: A.N.Kuznetsov |
10 | * |
11 | */ |
12 | |
13 | #define pr_fmt(fmt) "IPv4: " fmt |
14 | |
15 | #include <linux/capability.h> |
16 | #include <linux/module.h> |
17 | #include <linux/slab.h> |
18 | #include <linux/types.h> |
19 | #include <linux/uaccess.h> |
20 | #include <asm/unaligned.h> |
21 | #include <linux/skbuff.h> |
22 | #include <linux/ip.h> |
23 | #include <linux/icmp.h> |
24 | #include <linux/netdevice.h> |
25 | #include <linux/rtnetlink.h> |
26 | #include <net/sock.h> |
27 | #include <net/ip.h> |
28 | #include <net/icmp.h> |
29 | #include <net/route.h> |
30 | #include <net/cipso_ipv4.h> |
31 | #include <net/ip_fib.h> |
32 | |
33 | /* |
34 | * Write options to IP header, record destination address to |
35 | * source route option, address of outgoing interface |
36 | * (we should already know it, so that this function is allowed be |
37 | * called only after routing decision) and timestamp, |
38 | * if we originate this datagram. |
39 | * |
40 | * daddr is real destination address, next hop is recorded in IP header. |
41 | * saddr is address of outgoing interface. |
42 | */ |
43 | |
44 | void ip_options_build(struct sk_buff *skb, struct ip_options *opt, |
45 | __be32 daddr, struct rtable *rt) |
46 | { |
47 | unsigned char *iph = skb_network_header(skb); |
48 | |
49 | memcpy(&(IPCB(skb)->opt), opt, sizeof(struct ip_options)); |
50 | memcpy(iph + sizeof(struct iphdr), opt->__data, opt->optlen); |
51 | opt = &(IPCB(skb)->opt); |
52 | |
53 | if (opt->srr) |
54 | memcpy(iph + opt->srr + iph[opt->srr + 1] - 4, &daddr, 4); |
55 | |
56 | if (opt->rr_needaddr) |
57 | ip_rt_get_source(src: iph + opt->rr + iph[opt->rr + 2] - 5, skb, rt); |
58 | if (opt->ts_needaddr) |
59 | ip_rt_get_source(src: iph + opt->ts + iph[opt->ts + 2] - 9, skb, rt); |
60 | if (opt->ts_needtime) { |
61 | __be32 midtime; |
62 | |
63 | midtime = inet_current_timestamp(); |
64 | memcpy(iph + opt->ts + iph[opt->ts + 2] - 5, &midtime, 4); |
65 | } |
66 | } |
67 | |
68 | /* |
69 | * Provided (sopt, skb) points to received options, |
70 | * build in dopt compiled option set appropriate for answering. |
71 | * i.e. invert SRR option, copy anothers, |
72 | * and grab room in RR/TS options. |
73 | * |
74 | * NOTE: dopt cannot point to skb. |
75 | */ |
76 | |
77 | int __ip_options_echo(struct net *net, struct ip_options *dopt, |
78 | struct sk_buff *skb, const struct ip_options *sopt) |
79 | { |
80 | unsigned char *sptr, *dptr; |
81 | int soffset, doffset; |
82 | int optlen; |
83 | |
84 | memset(dopt, 0, sizeof(struct ip_options)); |
85 | |
86 | if (sopt->optlen == 0) |
87 | return 0; |
88 | |
89 | sptr = skb_network_header(skb); |
90 | dptr = dopt->__data; |
91 | |
92 | if (sopt->rr) { |
93 | optlen = sptr[sopt->rr+1]; |
94 | soffset = sptr[sopt->rr+2]; |
95 | dopt->rr = dopt->optlen + sizeof(struct iphdr); |
96 | memcpy(dptr, sptr+sopt->rr, optlen); |
97 | if (sopt->rr_needaddr && soffset <= optlen) { |
98 | if (soffset + 3 > optlen) |
99 | return -EINVAL; |
100 | dptr[2] = soffset + 4; |
101 | dopt->rr_needaddr = 1; |
102 | } |
103 | dptr += optlen; |
104 | dopt->optlen += optlen; |
105 | } |
106 | if (sopt->ts) { |
107 | optlen = sptr[sopt->ts+1]; |
108 | soffset = sptr[sopt->ts+2]; |
109 | dopt->ts = dopt->optlen + sizeof(struct iphdr); |
110 | memcpy(dptr, sptr+sopt->ts, optlen); |
111 | if (soffset <= optlen) { |
112 | if (sopt->ts_needaddr) { |
113 | if (soffset + 3 > optlen) |
114 | return -EINVAL; |
115 | dopt->ts_needaddr = 1; |
116 | soffset += 4; |
117 | } |
118 | if (sopt->ts_needtime) { |
119 | if (soffset + 3 > optlen) |
120 | return -EINVAL; |
121 | if ((dptr[3]&0xF) != IPOPT_TS_PRESPEC) { |
122 | dopt->ts_needtime = 1; |
123 | soffset += 4; |
124 | } else { |
125 | dopt->ts_needtime = 0; |
126 | |
127 | if (soffset + 7 <= optlen) { |
128 | __be32 addr; |
129 | |
130 | memcpy(&addr, dptr+soffset-1, 4); |
131 | if (inet_addr_type(net, addr) != RTN_UNICAST) { |
132 | dopt->ts_needtime = 1; |
133 | soffset += 8; |
134 | } |
135 | } |
136 | } |
137 | } |
138 | dptr[2] = soffset; |
139 | } |
140 | dptr += optlen; |
141 | dopt->optlen += optlen; |
142 | } |
143 | if (sopt->srr) { |
144 | unsigned char *start = sptr+sopt->srr; |
145 | __be32 faddr; |
146 | |
147 | optlen = start[1]; |
148 | soffset = start[2]; |
149 | doffset = 0; |
150 | if (soffset > optlen) |
151 | soffset = optlen + 1; |
152 | soffset -= 4; |
153 | if (soffset > 3) { |
154 | memcpy(&faddr, &start[soffset-1], 4); |
155 | for (soffset -= 4, doffset = 4; soffset > 3; soffset -= 4, doffset += 4) |
156 | memcpy(&dptr[doffset-1], &start[soffset-1], 4); |
157 | /* |
158 | * RFC1812 requires to fix illegal source routes. |
159 | */ |
160 | if (memcmp(p: &ip_hdr(skb)->saddr, |
161 | q: &start[soffset + 3], size: 4) == 0) |
162 | doffset -= 4; |
163 | } |
164 | if (doffset > 3) { |
165 | dopt->faddr = faddr; |
166 | dptr[0] = start[0]; |
167 | dptr[1] = doffset+3; |
168 | dptr[2] = 4; |
169 | dptr += doffset+3; |
170 | dopt->srr = dopt->optlen + sizeof(struct iphdr); |
171 | dopt->optlen += doffset+3; |
172 | dopt->is_strictroute = sopt->is_strictroute; |
173 | } |
174 | } |
175 | if (sopt->cipso) { |
176 | optlen = sptr[sopt->cipso+1]; |
177 | dopt->cipso = dopt->optlen+sizeof(struct iphdr); |
178 | memcpy(dptr, sptr+sopt->cipso, optlen); |
179 | dptr += optlen; |
180 | dopt->optlen += optlen; |
181 | } |
182 | while (dopt->optlen & 3) { |
183 | *dptr++ = IPOPT_END; |
184 | dopt->optlen++; |
185 | } |
186 | return 0; |
187 | } |
188 | |
189 | /* |
190 | * Options "fragmenting", just fill options not |
191 | * allowed in fragments with NOOPs. |
192 | * Simple and stupid 8), but the most efficient way. |
193 | */ |
194 | |
195 | void ip_options_fragment(struct sk_buff *skb) |
196 | { |
197 | unsigned char *optptr = skb_network_header(skb) + sizeof(struct iphdr); |
198 | struct ip_options *opt = &(IPCB(skb)->opt); |
199 | int l = opt->optlen; |
200 | int optlen; |
201 | |
202 | while (l > 0) { |
203 | switch (*optptr) { |
204 | case IPOPT_END: |
205 | return; |
206 | case IPOPT_NOOP: |
207 | l--; |
208 | optptr++; |
209 | continue; |
210 | } |
211 | optlen = optptr[1]; |
212 | if (optlen < 2 || optlen > l) |
213 | return; |
214 | if (!IPOPT_COPIED(*optptr)) |
215 | memset(optptr, IPOPT_NOOP, optlen); |
216 | l -= optlen; |
217 | optptr += optlen; |
218 | } |
219 | opt->ts = 0; |
220 | opt->rr = 0; |
221 | opt->rr_needaddr = 0; |
222 | opt->ts_needaddr = 0; |
223 | opt->ts_needtime = 0; |
224 | } |
225 | |
226 | /* helper used by ip_options_compile() to call fib_compute_spec_dst() |
227 | * at most one time. |
228 | */ |
229 | static void spec_dst_fill(__be32 *spec_dst, struct sk_buff *skb) |
230 | { |
231 | if (*spec_dst == htonl(INADDR_ANY)) |
232 | *spec_dst = fib_compute_spec_dst(skb); |
233 | } |
234 | |
235 | /* |
236 | * Verify options and fill pointers in struct options. |
237 | * Caller should clear *opt, and set opt->data. |
238 | * If opt == NULL, then skb->data should point to IP header. |
239 | */ |
240 | |
241 | int __ip_options_compile(struct net *net, |
242 | struct ip_options *opt, struct sk_buff *skb, |
243 | __be32 *info) |
244 | { |
245 | __be32 spec_dst = htonl(INADDR_ANY); |
246 | unsigned char *pp_ptr = NULL; |
247 | struct rtable *rt = NULL; |
248 | unsigned char *optptr; |
249 | unsigned char *iph; |
250 | int optlen, l; |
251 | |
252 | if (skb) { |
253 | rt = skb_rtable(skb); |
254 | optptr = (unsigned char *)&(ip_hdr(skb)[1]); |
255 | } else |
256 | optptr = opt->__data; |
257 | iph = optptr - sizeof(struct iphdr); |
258 | |
259 | for (l = opt->optlen; l > 0; ) { |
260 | switch (*optptr) { |
261 | case IPOPT_END: |
262 | for (optptr++, l--; l > 0; optptr++, l--) { |
263 | if (*optptr != IPOPT_END) { |
264 | *optptr = IPOPT_END; |
265 | opt->is_changed = 1; |
266 | } |
267 | } |
268 | goto eol; |
269 | case IPOPT_NOOP: |
270 | l--; |
271 | optptr++; |
272 | continue; |
273 | } |
274 | if (unlikely(l < 2)) { |
275 | pp_ptr = optptr; |
276 | goto error; |
277 | } |
278 | optlen = optptr[1]; |
279 | if (optlen < 2 || optlen > l) { |
280 | pp_ptr = optptr; |
281 | goto error; |
282 | } |
283 | switch (*optptr) { |
284 | case IPOPT_SSRR: |
285 | case IPOPT_LSRR: |
286 | if (optlen < 3) { |
287 | pp_ptr = optptr + 1; |
288 | goto error; |
289 | } |
290 | if (optptr[2] < 4) { |
291 | pp_ptr = optptr + 2; |
292 | goto error; |
293 | } |
294 | /* NB: cf RFC-1812 5.2.4.1 */ |
295 | if (opt->srr) { |
296 | pp_ptr = optptr; |
297 | goto error; |
298 | } |
299 | if (!skb) { |
300 | if (optptr[2] != 4 || optlen < 7 || ((optlen-3) & 3)) { |
301 | pp_ptr = optptr + 1; |
302 | goto error; |
303 | } |
304 | memcpy(&opt->faddr, &optptr[3], 4); |
305 | if (optlen > 7) |
306 | memmove(&optptr[3], &optptr[7], optlen-7); |
307 | } |
308 | opt->is_strictroute = (optptr[0] == IPOPT_SSRR); |
309 | opt->srr = optptr - iph; |
310 | break; |
311 | case IPOPT_RR: |
312 | if (opt->rr) { |
313 | pp_ptr = optptr; |
314 | goto error; |
315 | } |
316 | if (optlen < 3) { |
317 | pp_ptr = optptr + 1; |
318 | goto error; |
319 | } |
320 | if (optptr[2] < 4) { |
321 | pp_ptr = optptr + 2; |
322 | goto error; |
323 | } |
324 | if (optptr[2] <= optlen) { |
325 | if (optptr[2]+3 > optlen) { |
326 | pp_ptr = optptr + 2; |
327 | goto error; |
328 | } |
329 | if (rt) { |
330 | spec_dst_fill(spec_dst: &spec_dst, skb); |
331 | memcpy(&optptr[optptr[2]-1], &spec_dst, 4); |
332 | opt->is_changed = 1; |
333 | } |
334 | optptr[2] += 4; |
335 | opt->rr_needaddr = 1; |
336 | } |
337 | opt->rr = optptr - iph; |
338 | break; |
339 | case IPOPT_TIMESTAMP: |
340 | if (opt->ts) { |
341 | pp_ptr = optptr; |
342 | goto error; |
343 | } |
344 | if (optlen < 4) { |
345 | pp_ptr = optptr + 1; |
346 | goto error; |
347 | } |
348 | if (optptr[2] < 5) { |
349 | pp_ptr = optptr + 2; |
350 | goto error; |
351 | } |
352 | if (optptr[2] <= optlen) { |
353 | unsigned char *timeptr = NULL; |
354 | if (optptr[2]+3 > optlen) { |
355 | pp_ptr = optptr + 2; |
356 | goto error; |
357 | } |
358 | switch (optptr[3]&0xF) { |
359 | case IPOPT_TS_TSONLY: |
360 | if (skb) |
361 | timeptr = &optptr[optptr[2]-1]; |
362 | opt->ts_needtime = 1; |
363 | optptr[2] += 4; |
364 | break; |
365 | case IPOPT_TS_TSANDADDR: |
366 | if (optptr[2]+7 > optlen) { |
367 | pp_ptr = optptr + 2; |
368 | goto error; |
369 | } |
370 | if (rt) { |
371 | spec_dst_fill(spec_dst: &spec_dst, skb); |
372 | memcpy(&optptr[optptr[2]-1], &spec_dst, 4); |
373 | timeptr = &optptr[optptr[2]+3]; |
374 | } |
375 | opt->ts_needaddr = 1; |
376 | opt->ts_needtime = 1; |
377 | optptr[2] += 8; |
378 | break; |
379 | case IPOPT_TS_PRESPEC: |
380 | if (optptr[2]+7 > optlen) { |
381 | pp_ptr = optptr + 2; |
382 | goto error; |
383 | } |
384 | { |
385 | __be32 addr; |
386 | memcpy(&addr, &optptr[optptr[2]-1], 4); |
387 | if (inet_addr_type(net, addr) == RTN_UNICAST) |
388 | break; |
389 | if (skb) |
390 | timeptr = &optptr[optptr[2]+3]; |
391 | } |
392 | opt->ts_needtime = 1; |
393 | optptr[2] += 8; |
394 | break; |
395 | default: |
396 | if (!skb && !ns_capable(ns: net->user_ns, CAP_NET_RAW)) { |
397 | pp_ptr = optptr + 3; |
398 | goto error; |
399 | } |
400 | break; |
401 | } |
402 | if (timeptr) { |
403 | __be32 midtime; |
404 | |
405 | midtime = inet_current_timestamp(); |
406 | memcpy(timeptr, &midtime, 4); |
407 | opt->is_changed = 1; |
408 | } |
409 | } else if ((optptr[3]&0xF) != IPOPT_TS_PRESPEC) { |
410 | unsigned int overflow = optptr[3]>>4; |
411 | if (overflow == 15) { |
412 | pp_ptr = optptr + 3; |
413 | goto error; |
414 | } |
415 | if (skb) { |
416 | optptr[3] = (optptr[3]&0xF)|((overflow+1)<<4); |
417 | opt->is_changed = 1; |
418 | } |
419 | } |
420 | opt->ts = optptr - iph; |
421 | break; |
422 | case IPOPT_RA: |
423 | if (optlen < 4) { |
424 | pp_ptr = optptr + 1; |
425 | goto error; |
426 | } |
427 | if (optptr[2] == 0 && optptr[3] == 0) |
428 | opt->router_alert = optptr - iph; |
429 | break; |
430 | case IPOPT_CIPSO: |
431 | if ((!skb && !ns_capable(ns: net->user_ns, CAP_NET_RAW)) || opt->cipso) { |
432 | pp_ptr = optptr; |
433 | goto error; |
434 | } |
435 | opt->cipso = optptr - iph; |
436 | if (cipso_v4_validate(skb, option: &optptr)) { |
437 | pp_ptr = optptr; |
438 | goto error; |
439 | } |
440 | break; |
441 | case IPOPT_SEC: |
442 | case IPOPT_SID: |
443 | default: |
444 | if (!skb && !ns_capable(ns: net->user_ns, CAP_NET_RAW)) { |
445 | pp_ptr = optptr; |
446 | goto error; |
447 | } |
448 | break; |
449 | } |
450 | l -= optlen; |
451 | optptr += optlen; |
452 | } |
453 | |
454 | eol: |
455 | if (!pp_ptr) |
456 | return 0; |
457 | |
458 | error: |
459 | if (info) |
460 | *info = htonl((pp_ptr-iph)<<24); |
461 | return -EINVAL; |
462 | } |
463 | EXPORT_SYMBOL(__ip_options_compile); |
464 | |
465 | int ip_options_compile(struct net *net, |
466 | struct ip_options *opt, struct sk_buff *skb) |
467 | { |
468 | int ret; |
469 | __be32 info; |
470 | |
471 | ret = __ip_options_compile(net, opt, skb, &info); |
472 | if (ret != 0 && skb) |
473 | icmp_send(skb_in: skb, ICMP_PARAMETERPROB, code: 0, info); |
474 | return ret; |
475 | } |
476 | EXPORT_SYMBOL(ip_options_compile); |
477 | |
478 | /* |
479 | * Undo all the changes done by ip_options_compile(). |
480 | */ |
481 | |
482 | void ip_options_undo(struct ip_options *opt) |
483 | { |
484 | if (opt->srr) { |
485 | unsigned char *optptr = opt->__data + opt->srr - sizeof(struct iphdr); |
486 | |
487 | memmove(optptr + 7, optptr + 3, optptr[1] - 7); |
488 | memcpy(optptr + 3, &opt->faddr, 4); |
489 | } |
490 | if (opt->rr_needaddr) { |
491 | unsigned char *optptr = opt->__data + opt->rr - sizeof(struct iphdr); |
492 | |
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 | |
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 | |
512 | int ip_options_get(struct net *net, struct ip_options_rcu **optp, |
513 | sockptr_t data, int optlen) |
514 | { |
515 | struct ip_options_rcu *opt; |
516 | |
517 | opt = kzalloc(size: sizeof(struct ip_options_rcu) + ((optlen + 3) & ~3), |
518 | GFP_KERNEL); |
519 | if (!opt) |
520 | return -ENOMEM; |
521 | if (optlen && copy_from_sockptr(dst: opt->opt.__data, src: data, size: optlen)) { |
522 | kfree(objp: opt); |
523 | return -EFAULT; |
524 | } |
525 | |
526 | while (optlen & 3) |
527 | opt->opt.__data[optlen++] = IPOPT_END; |
528 | opt->opt.optlen = optlen; |
529 | if (optlen && ip_options_compile(net, &opt->opt, NULL)) { |
530 | kfree(objp: opt); |
531 | return -EINVAL; |
532 | } |
533 | kfree(objp: *optp); |
534 | *optp = opt; |
535 | return 0; |
536 | } |
537 | |
538 | void ip_forward_options(struct sk_buff *skb) |
539 | { |
540 | struct ip_options *opt = &(IPCB(skb)->opt); |
541 | unsigned char *optptr; |
542 | struct rtable *rt = skb_rtable(skb); |
543 | unsigned char *raw = skb_network_header(skb); |
544 | |
545 | if (opt->rr_needaddr) { |
546 | optptr = (unsigned char *)raw + opt->rr; |
547 | ip_rt_get_source(src: &optptr[optptr[2]-5], skb, rt); |
548 | opt->is_changed = 1; |
549 | } |
550 | if (opt->srr_is_hit) { |
551 | int srrptr, srrspace; |
552 | |
553 | optptr = raw + opt->srr; |
554 | |
555 | for ( srrptr = optptr[2], srrspace = optptr[1]; |
556 | srrptr <= srrspace; |
557 | srrptr += 4 |
558 | ) { |
559 | if (srrptr + 3 > srrspace) |
560 | break; |
561 | if (memcmp(p: &opt->nexthop, q: &optptr[srrptr-1], size: 4) == 0) |
562 | break; |
563 | } |
564 | if (srrptr + 3 <= srrspace) { |
565 | opt->is_changed = 1; |
566 | ip_hdr(skb)->daddr = opt->nexthop; |
567 | ip_rt_get_source(src: &optptr[srrptr-1], skb, rt); |
568 | optptr[2] = srrptr+4; |
569 | } else { |
570 | net_crit_ratelimited("%s(): Argh! Destination lost!\n" , |
571 | __func__); |
572 | } |
573 | if (opt->ts_needaddr) { |
574 | optptr = raw + opt->ts; |
575 | ip_rt_get_source(src: &optptr[optptr[2]-9], skb, rt); |
576 | opt->is_changed = 1; |
577 | } |
578 | } |
579 | if (opt->is_changed) { |
580 | opt->is_changed = 0; |
581 | ip_send_check(ip: ip_hdr(skb)); |
582 | } |
583 | } |
584 | |
585 | int ip_options_rcv_srr(struct sk_buff *skb, struct net_device *dev) |
586 | { |
587 | struct ip_options *opt = &(IPCB(skb)->opt); |
588 | int srrspace, srrptr; |
589 | __be32 nexthop; |
590 | struct iphdr *iph = ip_hdr(skb); |
591 | unsigned char *optptr = skb_network_header(skb) + opt->srr; |
592 | struct rtable *rt = skb_rtable(skb); |
593 | struct rtable *rt2; |
594 | unsigned long orefdst; |
595 | int err; |
596 | |
597 | if (!rt) |
598 | return 0; |
599 | |
600 | if (skb->pkt_type != PACKET_HOST) |
601 | return -EINVAL; |
602 | if (rt->rt_type == RTN_UNICAST) { |
603 | if (!opt->is_strictroute) |
604 | return 0; |
605 | icmp_send(skb_in: skb, ICMP_PARAMETERPROB, code: 0, htonl(16<<24)); |
606 | return -EINVAL; |
607 | } |
608 | if (rt->rt_type != RTN_LOCAL) |
609 | return -EINVAL; |
610 | |
611 | for (srrptr = optptr[2], srrspace = optptr[1]; srrptr <= srrspace; srrptr += 4) { |
612 | if (srrptr + 3 > srrspace) { |
613 | icmp_send(skb_in: skb, ICMP_PARAMETERPROB, code: 0, htonl((opt->srr+2)<<24)); |
614 | return -EINVAL; |
615 | } |
616 | memcpy(&nexthop, &optptr[srrptr-1], 4); |
617 | |
618 | orefdst = skb->_skb_refdst; |
619 | skb_dst_set(skb, NULL); |
620 | err = ip_route_input(skb, dst: nexthop, src: iph->saddr, tos: iph->tos, devin: dev); |
621 | rt2 = skb_rtable(skb); |
622 | if (err || (rt2->rt_type != RTN_UNICAST && rt2->rt_type != RTN_LOCAL)) { |
623 | skb_dst_drop(skb); |
624 | skb->_skb_refdst = orefdst; |
625 | return -EINVAL; |
626 | } |
627 | refdst_drop(refdst: orefdst); |
628 | if (rt2->rt_type != RTN_LOCAL) |
629 | break; |
630 | /* Superfast 8) loopback forward */ |
631 | iph->daddr = nexthop; |
632 | opt->is_changed = 1; |
633 | } |
634 | if (srrptr <= srrspace) { |
635 | opt->srr_is_hit = 1; |
636 | opt->nexthop = nexthop; |
637 | opt->is_changed = 1; |
638 | } |
639 | return 0; |
640 | } |
641 | EXPORT_SYMBOL(ip_options_rcv_srr); |
642 | |