Commit | Line | Data |
---|---|---|
b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
1da177e4 LT |
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 | * | |
1da177e4 | 9 | * Authors: A.N.Kuznetsov |
e905a9ed | 10 | * |
1da177e4 LT |
11 | */ |
12 | ||
afd46503 JP |
13 | #define pr_fmt(fmt) "IPv4: " fmt |
14 | ||
4fc268d2 | 15 | #include <linux/capability.h> |
1da177e4 | 16 | #include <linux/module.h> |
5a0e3ad6 | 17 | #include <linux/slab.h> |
1da177e4 | 18 | #include <linux/types.h> |
7c0f6ba6 | 19 | #include <linux/uaccess.h> |
48bdf072 | 20 | #include <asm/unaligned.h> |
1da177e4 LT |
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> | |
14c85021 | 29 | #include <net/route.h> |
11a03f78 | 30 | #include <net/cipso_ipv4.h> |
35ebf65e | 31 | #include <net/ip_fib.h> |
1da177e4 | 32 | |
e905a9ed | 33 | /* |
1da177e4 LT |
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 | ||
f6d8bd05 | 44 | void ip_options_build(struct sk_buff *skb, struct ip_options *opt, |
8e36360a | 45 | __be32 daddr, struct rtable *rt, int is_frag) |
1da177e4 | 46 | { |
d56f90a7 | 47 | unsigned char *iph = skb_network_header(skb); |
1da177e4 LT |
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); | |
1da177e4 LT |
52 | |
53 | if (opt->srr) | |
54 | memcpy(iph+opt->srr+iph[opt->srr+1]-4, &daddr, 4); | |
55 | ||
56 | if (!is_frag) { | |
57 | if (opt->rr_needaddr) | |
8e36360a | 58 | ip_rt_get_source(iph+opt->rr+iph[opt->rr+2]-5, skb, rt); |
1da177e4 | 59 | if (opt->ts_needaddr) |
8e36360a | 60 | ip_rt_get_source(iph+opt->ts+iph[opt->ts+2]-9, skb, rt); |
1da177e4 | 61 | if (opt->ts_needtime) { |
e25d2ca6 | 62 | __be32 midtime; |
822c8685 DD |
63 | |
64 | midtime = inet_current_timestamp(); | |
1da177e4 LT |
65 | memcpy(iph+opt->ts+iph[opt->ts+2]-5, &midtime, 4); |
66 | } | |
67 | return; | |
68 | } | |
69 | if (opt->rr) { | |
70 | memset(iph+opt->rr, IPOPT_NOP, iph[opt->rr+1]); | |
71 | opt->rr = 0; | |
72 | opt->rr_needaddr = 0; | |
73 | } | |
74 | if (opt->ts) { | |
75 | memset(iph+opt->ts, IPOPT_NOP, iph[opt->ts+1]); | |
76 | opt->ts = 0; | |
77 | opt->ts_needaddr = opt->ts_needtime = 0; | |
78 | } | |
79 | } | |
80 | ||
e905a9ed | 81 | /* |
1da177e4 LT |
82 | * Provided (sopt, skb) points to received options, |
83 | * build in dopt compiled option set appropriate for answering. | |
84 | * i.e. invert SRR option, copy anothers, | |
85 | * and grab room in RR/TS options. | |
86 | * | |
87 | * NOTE: dopt cannot point to skb. | |
88 | */ | |
89 | ||
91ed1e66 PA |
90 | int __ip_options_echo(struct net *net, struct ip_options *dopt, |
91 | struct sk_buff *skb, const struct ip_options *sopt) | |
1da177e4 | 92 | { |
1da177e4 LT |
93 | unsigned char *sptr, *dptr; |
94 | int soffset, doffset; | |
95 | int optlen; | |
1da177e4 LT |
96 | |
97 | memset(dopt, 0, sizeof(struct ip_options)); | |
98 | ||
f6d8bd05 | 99 | if (sopt->optlen == 0) |
1da177e4 | 100 | return 0; |
1da177e4 | 101 | |
d56f90a7 | 102 | sptr = skb_network_header(skb); |
1da177e4 LT |
103 | dptr = dopt->__data; |
104 | ||
1da177e4 LT |
105 | if (sopt->rr) { |
106 | optlen = sptr[sopt->rr+1]; | |
107 | soffset = sptr[sopt->rr+2]; | |
108 | dopt->rr = dopt->optlen + sizeof(struct iphdr); | |
109 | memcpy(dptr, sptr+sopt->rr, optlen); | |
110 | if (sopt->rr_needaddr && soffset <= optlen) { | |
111 | if (soffset + 3 > optlen) | |
112 | return -EINVAL; | |
113 | dptr[2] = soffset + 4; | |
114 | dopt->rr_needaddr = 1; | |
115 | } | |
116 | dptr += optlen; | |
117 | dopt->optlen += optlen; | |
118 | } | |
119 | if (sopt->ts) { | |
120 | optlen = sptr[sopt->ts+1]; | |
121 | soffset = sptr[sopt->ts+2]; | |
122 | dopt->ts = dopt->optlen + sizeof(struct iphdr); | |
123 | memcpy(dptr, sptr+sopt->ts, optlen); | |
124 | if (soffset <= optlen) { | |
125 | if (sopt->ts_needaddr) { | |
126 | if (soffset + 3 > optlen) | |
127 | return -EINVAL; | |
128 | dopt->ts_needaddr = 1; | |
129 | soffset += 4; | |
130 | } | |
131 | if (sopt->ts_needtime) { | |
132 | if (soffset + 3 > optlen) | |
133 | return -EINVAL; | |
134 | if ((dptr[3]&0xF) != IPOPT_TS_PRESPEC) { | |
135 | dopt->ts_needtime = 1; | |
136 | soffset += 4; | |
137 | } else { | |
138 | dopt->ts_needtime = 0; | |
139 | ||
8628bd8a | 140 | if (soffset + 7 <= optlen) { |
fd683222 | 141 | __be32 addr; |
1da177e4 | 142 | |
8628bd8a | 143 | memcpy(&addr, dptr+soffset-1, 4); |
91ed1e66 | 144 | if (inet_addr_type(net, addr) != RTN_UNICAST) { |
1da177e4 LT |
145 | dopt->ts_needtime = 1; |
146 | soffset += 8; | |
147 | } | |
148 | } | |
149 | } | |
150 | } | |
151 | dptr[2] = soffset; | |
152 | } | |
153 | dptr += optlen; | |
154 | dopt->optlen += optlen; | |
155 | } | |
156 | if (sopt->srr) { | |
f6d8bd05 | 157 | unsigned char *start = sptr+sopt->srr; |
3ca3c68e | 158 | __be32 faddr; |
1da177e4 LT |
159 | |
160 | optlen = start[1]; | |
161 | soffset = start[2]; | |
162 | doffset = 0; | |
163 | if (soffset > optlen) | |
164 | soffset = optlen + 1; | |
165 | soffset -= 4; | |
166 | if (soffset > 3) { | |
167 | memcpy(&faddr, &start[soffset-1], 4); | |
a22318e8 | 168 | for (soffset -= 4, doffset = 4; soffset > 3; soffset -= 4, doffset += 4) |
1da177e4 LT |
169 | memcpy(&dptr[doffset-1], &start[soffset-1], 4); |
170 | /* | |
171 | * RFC1812 requires to fix illegal source routes. | |
172 | */ | |
eddc9ec5 ACM |
173 | if (memcmp(&ip_hdr(skb)->saddr, |
174 | &start[soffset + 3], 4) == 0) | |
1da177e4 LT |
175 | doffset -= 4; |
176 | } | |
177 | if (doffset > 3) { | |
1da177e4 LT |
178 | dopt->faddr = faddr; |
179 | dptr[0] = start[0]; | |
180 | dptr[1] = doffset+3; | |
181 | dptr[2] = 4; | |
182 | dptr += doffset+3; | |
183 | dopt->srr = dopt->optlen + sizeof(struct iphdr); | |
184 | dopt->optlen += doffset+3; | |
185 | dopt->is_strictroute = sopt->is_strictroute; | |
186 | } | |
187 | } | |
11a03f78 PM |
188 | if (sopt->cipso) { |
189 | optlen = sptr[sopt->cipso+1]; | |
190 | dopt->cipso = dopt->optlen+sizeof(struct iphdr); | |
191 | memcpy(dptr, sptr+sopt->cipso, optlen); | |
192 | dptr += optlen; | |
193 | dopt->optlen += optlen; | |
194 | } | |
1da177e4 LT |
195 | while (dopt->optlen & 3) { |
196 | *dptr++ = IPOPT_END; | |
197 | dopt->optlen++; | |
198 | } | |
199 | return 0; | |
200 | } | |
201 | ||
202 | /* | |
203 | * Options "fragmenting", just fill options not | |
204 | * allowed in fragments with NOOPs. | |
205 | * Simple and stupid 8), but the most efficient way. | |
206 | */ | |
207 | ||
5e73ea1a | 208 | void ip_options_fragment(struct sk_buff *skb) |
1da177e4 | 209 | { |
d56f90a7 | 210 | unsigned char *optptr = skb_network_header(skb) + sizeof(struct iphdr); |
5e73ea1a | 211 | struct ip_options *opt = &(IPCB(skb)->opt); |
1da177e4 LT |
212 | int l = opt->optlen; |
213 | int optlen; | |
214 | ||
215 | while (l > 0) { | |
216 | switch (*optptr) { | |
217 | case IPOPT_END: | |
218 | return; | |
219 | case IPOPT_NOOP: | |
220 | l--; | |
221 | optptr++; | |
222 | continue; | |
223 | } | |
224 | optlen = optptr[1]; | |
a22318e8 | 225 | if (optlen < 2 || optlen > l) |
1da177e4 LT |
226 | return; |
227 | if (!IPOPT_COPIED(*optptr)) | |
228 | memset(optptr, IPOPT_NOOP, optlen); | |
229 | l -= optlen; | |
230 | optptr += optlen; | |
231 | } | |
232 | opt->ts = 0; | |
233 | opt->rr = 0; | |
234 | opt->rr_needaddr = 0; | |
235 | opt->ts_needaddr = 0; | |
236 | opt->ts_needtime = 0; | |
1da177e4 LT |
237 | } |
238 | ||
bf5e53e3 ED |
239 | /* helper used by ip_options_compile() to call fib_compute_spec_dst() |
240 | * at most one time. | |
241 | */ | |
242 | static void spec_dst_fill(__be32 *spec_dst, struct sk_buff *skb) | |
243 | { | |
244 | if (*spec_dst == htonl(INADDR_ANY)) | |
245 | *spec_dst = fib_compute_spec_dst(skb); | |
246 | } | |
247 | ||
1da177e4 LT |
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 | ||
980a7167 NS |
254 | int __ip_options_compile(struct net *net, |
255 | struct ip_options *opt, struct sk_buff *skb, | |
256 | __be32 *info) | |
1da177e4 | 257 | { |
bf5e53e3 | 258 | __be32 spec_dst = htonl(INADDR_ANY); |
5e73ea1a | 259 | unsigned char *pp_ptr = NULL; |
11604721 | 260 | struct rtable *rt = NULL; |
35ebf65e DM |
261 | unsigned char *optptr; |
262 | unsigned char *iph; | |
263 | int optlen, l; | |
1da177e4 | 264 | |
00db4124 | 265 | if (skb) { |
11604721 | 266 | rt = skb_rtable(skb); |
22aba383 DL |
267 | optptr = (unsigned char *)&(ip_hdr(skb)[1]); |
268 | } else | |
10fe7d85 | 269 | optptr = opt->__data; |
22aba383 | 270 | iph = optptr - sizeof(struct iphdr); |
1da177e4 LT |
271 | |
272 | for (l = opt->optlen; l > 0; ) { | |
273 | switch (*optptr) { | |
dd9b4559 | 274 | case IPOPT_END: |
a22318e8 | 275 | for (optptr++, l--; l > 0; optptr++, l--) { |
1da177e4 LT |
276 | if (*optptr != IPOPT_END) { |
277 | *optptr = IPOPT_END; | |
278 | opt->is_changed = 1; | |
279 | } | |
280 | } | |
281 | goto eol; | |
dd9b4559 | 282 | case IPOPT_NOOP: |
1da177e4 LT |
283 | l--; |
284 | optptr++; | |
285 | continue; | |
286 | } | |
10ec9472 ED |
287 | if (unlikely(l < 2)) { |
288 | pp_ptr = optptr; | |
289 | goto error; | |
290 | } | |
1da177e4 | 291 | optlen = optptr[1]; |
a22318e8 | 292 | if (optlen < 2 || optlen > l) { |
1da177e4 LT |
293 | pp_ptr = optptr; |
294 | goto error; | |
295 | } | |
296 | switch (*optptr) { | |
dd9b4559 WC |
297 | case IPOPT_SSRR: |
298 | case IPOPT_LSRR: | |
1da177e4 LT |
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; | |
dd9b4559 | 324 | case IPOPT_RR: |
1da177e4 LT |
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 | } | |
11604721 | 342 | if (rt) { |
bf5e53e3 | 343 | spec_dst_fill(&spec_dst, skb); |
35ebf65e | 344 | memcpy(&optptr[optptr[2]-1], &spec_dst, 4); |
1da177e4 LT |
345 | opt->is_changed = 1; |
346 | } | |
347 | optptr[2] += 4; | |
348 | opt->rr_needaddr = 1; | |
349 | } | |
350 | opt->rr = optptr - iph; | |
351 | break; | |
dd9b4559 | 352 | case IPOPT_TIMESTAMP: |
1da177e4 LT |
353 | if (opt->ts) { |
354 | pp_ptr = optptr; | |
355 | goto error; | |
356 | } | |
357 | if (optlen < 4) { | |
358 | pp_ptr = optptr + 1; | |
359 | goto error; | |
360 | } | |
361 | if (optptr[2] < 5) { | |
362 | pp_ptr = optptr + 2; | |
363 | goto error; | |
364 | } | |
365 | if (optptr[2] <= optlen) { | |
48bdf072 | 366 | unsigned char *timeptr = NULL; |
5a2b646f | 367 | if (optptr[2]+3 > optlen) { |
1da177e4 LT |
368 | pp_ptr = optptr + 2; |
369 | goto error; | |
370 | } | |
371 | switch (optptr[3]&0xF) { | |
dd9b4559 | 372 | case IPOPT_TS_TSONLY: |
e905a9ed | 373 | if (skb) |
48bdf072 | 374 | timeptr = &optptr[optptr[2]-1]; |
1da177e4 LT |
375 | opt->ts_needtime = 1; |
376 | optptr[2] += 4; | |
377 | break; | |
dd9b4559 | 378 | case IPOPT_TS_TSANDADDR: |
5a2b646f | 379 | if (optptr[2]+7 > optlen) { |
1da177e4 LT |
380 | pp_ptr = optptr + 2; |
381 | goto error; | |
382 | } | |
11604721 | 383 | if (rt) { |
bf5e53e3 | 384 | spec_dst_fill(&spec_dst, skb); |
35ebf65e | 385 | memcpy(&optptr[optptr[2]-1], &spec_dst, 4); |
48bdf072 | 386 | timeptr = &optptr[optptr[2]+3]; |
1da177e4 LT |
387 | } |
388 | opt->ts_needaddr = 1; | |
389 | opt->ts_needtime = 1; | |
390 | optptr[2] += 8; | |
391 | break; | |
dd9b4559 | 392 | case IPOPT_TS_PRESPEC: |
5a2b646f | 393 | if (optptr[2]+7 > optlen) { |
1da177e4 LT |
394 | pp_ptr = optptr + 2; |
395 | goto error; | |
396 | } | |
1da177e4 | 397 | { |
fd683222 | 398 | __be32 addr; |
1da177e4 | 399 | memcpy(&addr, &optptr[optptr[2]-1], 4); |
0e6bd4a1 | 400 | if (inet_addr_type(net, addr) == RTN_UNICAST) |
1da177e4 LT |
401 | break; |
402 | if (skb) | |
48bdf072 | 403 | timeptr = &optptr[optptr[2]+3]; |
1da177e4 LT |
404 | } |
405 | opt->ts_needtime = 1; | |
406 | optptr[2] += 8; | |
407 | break; | |
dd9b4559 | 408 | default: |
52e804c6 | 409 | if (!skb && !ns_capable(net->user_ns, CAP_NET_RAW)) { |
1da177e4 LT |
410 | pp_ptr = optptr + 3; |
411 | goto error; | |
412 | } | |
413 | break; | |
414 | } | |
415 | if (timeptr) { | |
822c8685 DD |
416 | __be32 midtime; |
417 | ||
418 | midtime = inet_current_timestamp(); | |
419 | memcpy(timeptr, &midtime, 4); | |
1da177e4 LT |
420 | opt->is_changed = 1; |
421 | } | |
fa2b04f4 | 422 | } else if ((optptr[3]&0xF) != IPOPT_TS_PRESPEC) { |
95c96174 | 423 | unsigned int overflow = optptr[3]>>4; |
1da177e4 LT |
424 | if (overflow == 15) { |
425 | pp_ptr = optptr + 3; | |
426 | goto error; | |
427 | } | |
1da177e4 LT |
428 | if (skb) { |
429 | optptr[3] = (optptr[3]&0xF)|((overflow+1)<<4); | |
430 | opt->is_changed = 1; | |
431 | } | |
432 | } | |
4660c7f4 | 433 | opt->ts = optptr - iph; |
1da177e4 | 434 | break; |
dd9b4559 | 435 | case IPOPT_RA: |
1da177e4 LT |
436 | if (optlen < 4) { |
437 | pp_ptr = optptr + 1; | |
438 | goto error; | |
439 | } | |
440 | if (optptr[2] == 0 && optptr[3] == 0) | |
441 | opt->router_alert = optptr - iph; | |
442 | break; | |
dd9b4559 | 443 | case IPOPT_CIPSO: |
52e804c6 | 444 | if ((!skb && !ns_capable(net->user_ns, CAP_NET_RAW)) || opt->cipso) { |
11a03f78 PM |
445 | pp_ptr = optptr; |
446 | goto error; | |
447 | } | |
448 | opt->cipso = optptr - iph; | |
15c45f7b | 449 | if (cipso_v4_validate(skb, &optptr)) { |
11a03f78 PM |
450 | pp_ptr = optptr; |
451 | goto error; | |
452 | } | |
453 | break; | |
dd9b4559 WC |
454 | case IPOPT_SEC: |
455 | case IPOPT_SID: | |
456 | default: | |
52e804c6 | 457 | if (!skb && !ns_capable(net->user_ns, CAP_NET_RAW)) { |
1da177e4 LT |
458 | pp_ptr = optptr; |
459 | goto error; | |
460 | } | |
461 | break; | |
462 | } | |
463 | l -= optlen; | |
464 | optptr += optlen; | |
465 | } | |
466 | ||
467 | eol: | |
468 | if (!pp_ptr) | |
469 | return 0; | |
470 | ||
471 | error: | |
980a7167 NS |
472 | if (info) |
473 | *info = htonl((pp_ptr-iph)<<24); | |
1da177e4 LT |
474 | return -EINVAL; |
475 | } | |
980a7167 NS |
476 | |
477 | int ip_options_compile(struct net *net, | |
478 | struct ip_options *opt, struct sk_buff *skb) | |
479 | { | |
480 | int ret; | |
481 | __be32 info; | |
482 | ||
483 | ret = __ip_options_compile(net, opt, skb, &info); | |
484 | if (ret != 0 && skb) | |
485 | icmp_send(skb, ICMP_PARAMETERPROB, 0, info); | |
486 | return ret; | |
487 | } | |
462fb2af | 488 | EXPORT_SYMBOL(ip_options_compile); |
1da177e4 LT |
489 | |
490 | /* | |
491 | * Undo all the changes done by ip_options_compile(). | |
492 | */ | |
493 | ||
5e73ea1a | 494 | void ip_options_undo(struct ip_options *opt) |
1da177e4 LT |
495 | { |
496 | if (opt->srr) { | |
5e73ea1a | 497 | unsigned char *optptr = opt->__data+opt->srr-sizeof(struct iphdr); |
1da177e4 LT |
498 | memmove(optptr+7, optptr+3, optptr[1]-7); |
499 | memcpy(optptr+3, &opt->faddr, 4); | |
500 | } | |
501 | if (opt->rr_needaddr) { | |
5e73ea1a | 502 | unsigned char *optptr = opt->__data+opt->rr-sizeof(struct iphdr); |
1da177e4 LT |
503 | optptr[2] -= 4; |
504 | memset(&optptr[optptr[2]-1], 0, 4); | |
505 | } | |
506 | if (opt->ts) { | |
5e73ea1a | 507 | unsigned char *optptr = opt->__data+opt->ts-sizeof(struct iphdr); |
1da177e4 LT |
508 | if (opt->ts_needtime) { |
509 | optptr[2] -= 4; | |
510 | memset(&optptr[optptr[2]-1], 0, 4); | |
511 | if ((optptr[3]&0xF) == IPOPT_TS_PRESPEC) | |
512 | optptr[2] -= 4; | |
513 | } | |
514 | if (opt->ts_needaddr) { | |
515 | optptr[2] -= 4; | |
516 | memset(&optptr[optptr[2]-1], 0, 4); | |
517 | } | |
518 | } | |
519 | } | |
520 | ||
f6d8bd05 | 521 | static struct ip_options_rcu *ip_options_get_alloc(const int optlen) |
1da177e4 | 522 | { |
f6d8bd05 | 523 | return kzalloc(sizeof(struct ip_options_rcu) + ((optlen + 3) & ~3), |
37640703 | 524 | GFP_KERNEL); |
4c6ea29d | 525 | } |
1da177e4 | 526 | |
f6d8bd05 ED |
527 | static int ip_options_get_finish(struct net *net, struct ip_options_rcu **optp, |
528 | struct ip_options_rcu *opt, int optlen) | |
4c6ea29d | 529 | { |
1da177e4 | 530 | while (optlen & 3) |
f6d8bd05 ED |
531 | opt->opt.__data[optlen++] = IPOPT_END; |
532 | opt->opt.optlen = optlen; | |
533 | if (optlen && ip_options_compile(net, &opt->opt, NULL)) { | |
1da177e4 LT |
534 | kfree(opt); |
535 | return -EINVAL; | |
536 | } | |
a51482bd | 537 | kfree(*optp); |
1da177e4 LT |
538 | *optp = opt; |
539 | return 0; | |
540 | } | |
541 | ||
f6d8bd05 | 542 | int ip_options_get_from_user(struct net *net, struct ip_options_rcu **optp, |
f2c4802b | 543 | unsigned char __user *data, int optlen) |
4c6ea29d | 544 | { |
f6d8bd05 | 545 | struct ip_options_rcu *opt = ip_options_get_alloc(optlen); |
4c6ea29d ACM |
546 | |
547 | if (!opt) | |
548 | return -ENOMEM; | |
f6d8bd05 | 549 | if (optlen && copy_from_user(opt->opt.__data, data, optlen)) { |
4c6ea29d ACM |
550 | kfree(opt); |
551 | return -EFAULT; | |
552 | } | |
f2c4802b | 553 | return ip_options_get_finish(net, optp, opt, optlen); |
4c6ea29d ACM |
554 | } |
555 | ||
f6d8bd05 | 556 | int ip_options_get(struct net *net, struct ip_options_rcu **optp, |
f2c4802b | 557 | unsigned char *data, int optlen) |
4c6ea29d | 558 | { |
f6d8bd05 | 559 | struct ip_options_rcu *opt = ip_options_get_alloc(optlen); |
4c6ea29d ACM |
560 | |
561 | if (!opt) | |
562 | return -ENOMEM; | |
563 | if (optlen) | |
f6d8bd05 | 564 | memcpy(opt->opt.__data, data, optlen); |
f2c4802b | 565 | return ip_options_get_finish(net, optp, opt, optlen); |
4c6ea29d ACM |
566 | } |
567 | ||
1da177e4 LT |
568 | void ip_forward_options(struct sk_buff *skb) |
569 | { | |
5e73ea1a DB |
570 | struct ip_options *opt = &(IPCB(skb)->opt); |
571 | unsigned char *optptr; | |
511c3f92 | 572 | struct rtable *rt = skb_rtable(skb); |
d56f90a7 | 573 | unsigned char *raw = skb_network_header(skb); |
1da177e4 LT |
574 | |
575 | if (opt->rr_needaddr) { | |
576 | optptr = (unsigned char *)raw + opt->rr; | |
8e36360a | 577 | ip_rt_get_source(&optptr[optptr[2]-5], skb, rt); |
1da177e4 LT |
578 | opt->is_changed = 1; |
579 | } | |
580 | if (opt->srr_is_hit) { | |
581 | int srrptr, srrspace; | |
582 | ||
583 | optptr = raw + opt->srr; | |
584 | ||
a22318e8 | 585 | for ( srrptr = optptr[2], srrspace = optptr[1]; |
1da177e4 LT |
586 | srrptr <= srrspace; |
587 | srrptr += 4 | |
588 | ) { | |
589 | if (srrptr + 3 > srrspace) | |
590 | break; | |
ac8a4810 | 591 | if (memcmp(&opt->nexthop, &optptr[srrptr-1], 4) == 0) |
1da177e4 LT |
592 | break; |
593 | } | |
594 | if (srrptr + 3 <= srrspace) { | |
595 | opt->is_changed = 1; | |
ac8a4810 | 596 | ip_hdr(skb)->daddr = opt->nexthop; |
5dc7883f | 597 | ip_rt_get_source(&optptr[srrptr-1], skb, rt); |
1da177e4 | 598 | optptr[2] = srrptr+4; |
e87cc472 JP |
599 | } else { |
600 | net_crit_ratelimited("%s(): Argh! Destination lost!\n", | |
601 | __func__); | |
602 | } | |
1da177e4 LT |
603 | if (opt->ts_needaddr) { |
604 | optptr = raw + opt->ts; | |
8e36360a | 605 | ip_rt_get_source(&optptr[optptr[2]-9], skb, rt); |
1da177e4 LT |
606 | opt->is_changed = 1; |
607 | } | |
608 | } | |
609 | if (opt->is_changed) { | |
610 | opt->is_changed = 0; | |
eddc9ec5 | 611 | ip_send_check(ip_hdr(skb)); |
1da177e4 LT |
612 | } |
613 | } | |
614 | ||
16b71423 | 615 | int ip_options_rcv_srr(struct sk_buff *skb, struct net_device *dev) |
1da177e4 LT |
616 | { |
617 | struct ip_options *opt = &(IPCB(skb)->opt); | |
618 | int srrspace, srrptr; | |
9e12bb22 | 619 | __be32 nexthop; |
eddc9ec5 | 620 | struct iphdr *iph = ip_hdr(skb); |
d56f90a7 | 621 | unsigned char *optptr = skb_network_header(skb) + opt->srr; |
511c3f92 | 622 | struct rtable *rt = skb_rtable(skb); |
1da177e4 | 623 | struct rtable *rt2; |
7fee226a | 624 | unsigned long orefdst; |
1da177e4 LT |
625 | int err; |
626 | ||
10949550 | 627 | if (!rt) |
1da177e4 LT |
628 | return 0; |
629 | ||
630 | if (skb->pkt_type != PACKET_HOST) | |
631 | return -EINVAL; | |
632 | if (rt->rt_type == RTN_UNICAST) { | |
633 | if (!opt->is_strictroute) | |
634 | return 0; | |
635 | icmp_send(skb, ICMP_PARAMETERPROB, 0, htonl(16<<24)); | |
636 | return -EINVAL; | |
637 | } | |
638 | if (rt->rt_type != RTN_LOCAL) | |
639 | return -EINVAL; | |
640 | ||
a22318e8 | 641 | for (srrptr = optptr[2], srrspace = optptr[1]; srrptr <= srrspace; srrptr += 4) { |
1da177e4 LT |
642 | if (srrptr + 3 > srrspace) { |
643 | icmp_send(skb, ICMP_PARAMETERPROB, 0, htonl((opt->srr+2)<<24)); | |
644 | return -EINVAL; | |
645 | } | |
646 | memcpy(&nexthop, &optptr[srrptr-1], 4); | |
647 | ||
7fee226a | 648 | orefdst = skb->_skb_refdst; |
adf30907 | 649 | skb_dst_set(skb, NULL); |
16b71423 | 650 | err = ip_route_input(skb, nexthop, iph->saddr, iph->tos, dev); |
511c3f92 | 651 | rt2 = skb_rtable(skb); |
1da177e4 | 652 | if (err || (rt2->rt_type != RTN_UNICAST && rt2->rt_type != RTN_LOCAL)) { |
7fee226a ED |
653 | skb_dst_drop(skb); |
654 | skb->_skb_refdst = orefdst; | |
1da177e4 LT |
655 | return -EINVAL; |
656 | } | |
7fee226a | 657 | refdst_drop(orefdst); |
1da177e4 LT |
658 | if (rt2->rt_type != RTN_LOCAL) |
659 | break; | |
660 | /* Superfast 8) loopback forward */ | |
c30883bd | 661 | iph->daddr = nexthop; |
1da177e4 LT |
662 | opt->is_changed = 1; |
663 | } | |
664 | if (srrptr <= srrspace) { | |
665 | opt->srr_is_hit = 1; | |
ac8a4810 | 666 | opt->nexthop = nexthop; |
1da177e4 LT |
667 | opt->is_changed = 1; |
668 | } | |
669 | return 0; | |
670 | } | |
462fb2af | 671 | EXPORT_SYMBOL(ip_options_rcv_srr); |