Commit | Line | Data |
---|---|---|
5afc289d | 1 | /* |
0880b18e | 2 | * Copyright (c) 1982, 1986 Regents of the University of California. |
5afc289d MK |
3 | * All rights reserved. The Berkeley software License Agreement |
4 | * specifies the terms and conditions for redistribution. | |
5 | * | |
85b035eb | 6 | * @(#)ip_output.c 7.6 (Berkeley) %G% |
5afc289d | 7 | */ |
6e8b2eca | 8 | |
20666ad3 JB |
9 | #include "param.h" |
10 | #include "mbuf.h" | |
11 | #include "errno.h" | |
53ba4464 | 12 | #include "protosw.h" |
20666ad3 JB |
13 | #include "socket.h" |
14 | #include "socketvar.h" | |
f4d55810 SL |
15 | |
16 | #include "../net/if.h" | |
17 | #include "../net/route.h" | |
18 | ||
20666ad3 | 19 | #include "in.h" |
53ba4464 | 20 | #include "in_pcb.h" |
20666ad3 | 21 | #include "in_systm.h" |
dfce8240 | 22 | #include "in_var.h" |
20666ad3 JB |
23 | #include "ip.h" |
24 | #include "ip_var.h" | |
f4d55810 | 25 | |
b152d3c4 | 26 | #ifdef vax |
f112c673 | 27 | #include "../machine/mtpr.h" |
b152d3c4 | 28 | #endif |
ac904f92 | 29 | |
53ba4464 MK |
30 | struct mbuf *ip_insertoptions(); |
31 | ||
32 | /* | |
33 | * IP output. The packet in mbuf chain m contains a skeletal IP | |
99fe25ae MK |
34 | * header (with len, off, ttl, proto, tos, src, dst). |
35 | * The mbuf chain containing the packet will be freed. | |
36 | * The mbuf opt, if present, will not be freed. | |
53ba4464 | 37 | */ |
0e3f761f | 38 | ip_output(m, opt, ro, flags) |
2b4b57cd | 39 | struct mbuf *m; |
8a13b737 | 40 | struct mbuf *opt; |
ee787340 | 41 | struct route *ro; |
0e3f761f | 42 | int flags; |
ac904f92 | 43 | { |
53ba4464 | 44 | register struct ip *ip; |
8a13b737 | 45 | register struct ifnet *ifp; |
8a2f82db | 46 | int len, hlen = sizeof (struct ip), off, error = 0; |
ee787340 | 47 | struct route iproute; |
a8671e7e | 48 | struct sockaddr_in *dst; |
ac904f92 | 49 | |
53ba4464 MK |
50 | if (opt) |
51 | m = ip_insertoptions(m, opt, &hlen); | |
52 | ip = mtod(m, struct ip *); | |
e8d11875 | 53 | /* |
2b4b57cd | 54 | * Fill in IP header. |
e8d11875 | 55 | */ |
0e3f761f SL |
56 | if ((flags & IP_FORWARDING) == 0) { |
57 | ip->ip_v = IPVERSION; | |
58 | ip->ip_off &= IP_DF; | |
59 | ip->ip_id = htons(ip_id++); | |
4adcd589 | 60 | ip->ip_hl = hlen >> 2; |
53ba4464 MK |
61 | } else |
62 | hlen = ip->ip_hl << 2; | |
8a13b737 BJ |
63 | |
64 | /* | |
a13c006d | 65 | * Route packet. |
8a13b737 | 66 | */ |
ee787340 SL |
67 | if (ro == 0) { |
68 | ro = &iproute; | |
69 | bzero((caddr_t)ro, sizeof (*ro)); | |
70 | } | |
a8671e7e | 71 | dst = (struct sockaddr_in *)&ro->ro_dst; |
ccb87262 MK |
72 | /* |
73 | * If there is a cached route, | |
74 | * check that it is to the same destination | |
75 | * and is still up. If not, free it and try again. | |
76 | */ | |
77 | if (ro->ro_rt && ((ro->ro_rt->rt_flags & RTF_UP) == 0 || | |
78 | dst->sin_addr.s_addr != ip->ip_dst.s_addr)) { | |
79 | RTFREE(ro->ro_rt); | |
80 | ro->ro_rt = (struct rtentry *)0; | |
81 | } | |
ee787340 | 82 | if (ro->ro_rt == 0) { |
a8671e7e SL |
83 | dst->sin_family = AF_INET; |
84 | dst->sin_addr = ip->ip_dst; | |
d55475b1 MK |
85 | } |
86 | /* | |
87 | * If routing to interface only, | |
88 | * short circuit routing lookup. | |
89 | */ | |
90 | if (flags & IP_ROUTETOIF) { | |
91 | struct in_ifaddr *ia; | |
52c6a991 | 92 | |
4a9e3e93 | 93 | ia = (struct in_ifaddr *)ifa_ifwithdstaddr(dst); |
52c6a991 MK |
94 | if (ia == 0) |
95 | ia = in_iaonnetof(in_netof(ip->ip_dst)); | |
d55475b1 MK |
96 | if (ia == 0) { |
97 | error = ENETUNREACH; | |
98 | goto bad; | |
a13c006d | 99 | } |
d55475b1 MK |
100 | ifp = ia->ia_ifp; |
101 | } else { | |
d55475b1 MK |
102 | if (ro->ro_rt == 0) |
103 | rtalloc(ro); | |
104 | if (ro->ro_rt == 0 || (ifp = ro->ro_rt->rt_ifp) == 0) { | |
6d22aa47 MK |
105 | if (in_localaddr(ip->ip_dst)) |
106 | error = EHOSTUNREACH; | |
107 | else | |
108 | error = ENETUNREACH; | |
d55475b1 MK |
109 | goto bad; |
110 | } | |
111 | ro->ro_rt->rt_use++; | |
39e4cc50 | 112 | if (ro->ro_rt->rt_flags & RTF_GATEWAY) |
d55475b1 | 113 | dst = (struct sockaddr_in *)&ro->ro_rt->rt_gateway; |
0e3f761f | 114 | } |
5afc289d MK |
115 | #ifndef notdef |
116 | /* | |
117 | * If source address not specified yet, use address | |
118 | * of outgoing interface. | |
119 | */ | |
120 | if (ip->ip_src.s_addr == INADDR_ANY) { | |
121 | register struct in_ifaddr *ia; | |
122 | ||
123 | for (ia = in_ifaddr; ia; ia = ia->ia_next) | |
124 | if (ia->ia_ifp == ifp) { | |
125 | ip->ip_src = IA_SIN(ia)->sin_addr; | |
126 | break; | |
127 | } | |
128 | } | |
129 | #endif | |
a13c006d | 130 | /* |
af099287 SL |
131 | * Look for broadcast address and |
132 | * and verify user is allowed to send | |
19f96414 | 133 | * such a packet. |
a13c006d | 134 | */ |
dfce8240 | 135 | if (in_broadcast(dst->sin_addr)) { |
19f96414 SL |
136 | if ((ifp->if_flags & IFF_BROADCAST) == 0) { |
137 | error = EADDRNOTAVAIL; | |
138 | goto bad; | |
139 | } | |
0e3f761f | 140 | if ((flags & IP_ALLOWBROADCAST) == 0) { |
a13c006d | 141 | error = EACCES; |
ee787340 | 142 | goto bad; |
8a2f82db | 143 | } |
19f96414 SL |
144 | /* don't allow broadcast messages to be fragmented */ |
145 | if (ip->ip_len > ifp->if_mtu) { | |
146 | error = EMSGSIZE; | |
147 | goto bad; | |
148 | } | |
ee787340 | 149 | } |
ac904f92 | 150 | |
2b4b57cd BJ |
151 | /* |
152 | * If small enough for interface, can just send directly. | |
153 | */ | |
8a13b737 BJ |
154 | if (ip->ip_len <= ifp->if_mtu) { |
155 | ip->ip_len = htons((u_short)ip->ip_len); | |
156 | ip->ip_off = htons((u_short)ip->ip_off); | |
157 | ip->ip_sum = 0; | |
158 | ip->ip_sum = in_cksum(m, hlen); | |
a8671e7e | 159 | error = (*ifp->if_output)(ifp, m, (struct sockaddr *)dst); |
a13c006d | 160 | goto done; |
cdad2eb1 | 161 | } |
2b4b57cd BJ |
162 | |
163 | /* | |
164 | * Too large for interface; fragment if possible. | |
165 | * Must be able to put at least 8 bytes per fragment. | |
166 | */ | |
8a2f82db SL |
167 | if (ip->ip_off & IP_DF) { |
168 | error = EMSGSIZE; | |
2b4b57cd | 169 | goto bad; |
8a2f82db | 170 | } |
8a13b737 | 171 | len = (ifp->if_mtu - hlen) &~ 7; |
8a2f82db SL |
172 | if (len < 8) { |
173 | error = EMSGSIZE; | |
2b4b57cd | 174 | goto bad; |
8a2f82db | 175 | } |
2b4b57cd BJ |
176 | |
177 | /* | |
178 | * Discard IP header from logical mbuf for m_copy's sake. | |
179 | * Loop through length of segment, make a copy of each | |
180 | * part and output. | |
181 | */ | |
182 | m->m_len -= sizeof (struct ip); | |
183 | m->m_off += sizeof (struct ip); | |
0b49870f | 184 | for (off = 0; off < ip->ip_len-hlen; off += len) { |
22bd8cdc | 185 | struct mbuf *mh = m_get(M_DONTWAIT, MT_HEADER); |
2b4b57cd BJ |
186 | struct ip *mhip; |
187 | ||
8a2f82db SL |
188 | if (mh == 0) { |
189 | error = ENOBUFS; | |
2b4b57cd | 190 | goto bad; |
8a2f82db | 191 | } |
2b4b57cd BJ |
192 | mh->m_off = MMAXOFF - hlen; |
193 | mhip = mtod(mh, struct ip *); | |
194 | *mhip = *ip; | |
4ad99bae | 195 | if (hlen > sizeof (struct ip)) { |
2b4b57cd BJ |
196 | int olen = ip_optcopy(ip, mhip, off); |
197 | mh->m_len = sizeof (struct ip) + olen; | |
198 | } else | |
199 | mh->m_len = sizeof (struct ip); | |
2e7801e0 | 200 | mhip->ip_off = (off >> 3) + (ip->ip_off & ~IP_MF); |
4adcd589 MK |
201 | if (ip->ip_off & IP_MF) |
202 | mhip->ip_off |= IP_MF; | |
0b49870f BJ |
203 | if (off + len >= ip->ip_len-hlen) |
204 | len = mhip->ip_len = ip->ip_len - hlen - off; | |
2b4b57cd BJ |
205 | else { |
206 | mhip->ip_len = len; | |
207 | mhip->ip_off |= IP_MF; | |
98444525 | 208 | } |
e8f40dc9 | 209 | mhip->ip_len += sizeof (struct ip); |
e8f40dc9 | 210 | mhip->ip_len = htons((u_short)mhip->ip_len); |
2b4b57cd BJ |
211 | mh->m_next = m_copy(m, off, len); |
212 | if (mh->m_next == 0) { | |
2752c877 | 213 | (void) m_free(mh); |
8a2f82db | 214 | error = ENOBUFS; /* ??? */ |
2b4b57cd | 215 | goto bad; |
98444525 | 216 | } |
0b49870f | 217 | mhip->ip_off = htons((u_short)mhip->ip_off); |
0b49870f BJ |
218 | mhip->ip_sum = 0; |
219 | mhip->ip_sum = in_cksum(mh, hlen); | |
a8671e7e | 220 | if (error = (*ifp->if_output)(ifp, mh, (struct sockaddr *)dst)) |
8a2f82db | 221 | break; |
2b4b57cd BJ |
222 | } |
223 | bad: | |
224 | m_freem(m); | |
a13c006d | 225 | done: |
0e3f761f | 226 | if (ro == &iproute && (flags & IP_ROUTETOIF) == 0 && ro->ro_rt) |
a13c006d | 227 | RTFREE(ro->ro_rt); |
8a2f82db | 228 | return (error); |
2b4b57cd BJ |
229 | } |
230 | ||
53ba4464 MK |
231 | /* |
232 | * Insert IP options into preformed packet. | |
233 | * Adjust IP destination as required for IP source routing, | |
234 | * as indicated by a non-zero in_addr at the start of the options. | |
235 | */ | |
236 | struct mbuf * | |
237 | ip_insertoptions(m, opt, phlen) | |
238 | register struct mbuf *m; | |
239 | struct mbuf *opt; | |
240 | int *phlen; | |
241 | { | |
242 | register struct ipoption *p = mtod(opt, struct ipoption *); | |
243 | struct mbuf *n; | |
244 | register struct ip *ip = mtod(m, struct ip *); | |
8011f5df | 245 | unsigned optlen; |
53ba4464 MK |
246 | |
247 | optlen = opt->m_len - sizeof(p->ipopt_dst); | |
248 | if (p->ipopt_dst.s_addr) | |
249 | ip->ip_dst = p->ipopt_dst; | |
250 | if (m->m_off >= MMAXOFF || MMINOFF + optlen > m->m_off) { | |
251 | MGET(n, M_DONTWAIT, MT_HEADER); | |
252 | if (n == 0) | |
253 | return (m); | |
254 | m->m_len -= sizeof(struct ip); | |
255 | m->m_off += sizeof(struct ip); | |
256 | n->m_next = m; | |
257 | m = n; | |
258 | m->m_off = MMAXOFF - sizeof(struct ip) - optlen; | |
259 | m->m_len = optlen + sizeof(struct ip); | |
260 | bcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip)); | |
261 | } else { | |
262 | m->m_off -= optlen; | |
263 | m->m_len += optlen; | |
264 | ovbcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip)); | |
265 | } | |
266 | ip = mtod(m, struct ip *); | |
8011f5df | 267 | bcopy((caddr_t)p->ipopt_list, (caddr_t)(ip + 1), (unsigned)optlen); |
53ba4464 MK |
268 | *phlen = sizeof(struct ip) + optlen; |
269 | ip->ip_len += optlen; | |
270 | return (m); | |
271 | } | |
272 | ||
2b4b57cd BJ |
273 | /* |
274 | * Copy options from ip to jp. | |
4ad99bae | 275 | * If off is 0 all options are copied |
2b4b57cd BJ |
276 | * otherwise copy selectively. |
277 | */ | |
278 | ip_optcopy(ip, jp, off) | |
279 | struct ip *ip, *jp; | |
280 | int off; | |
281 | { | |
282 | register u_char *cp, *dp; | |
283 | int opt, optlen, cnt; | |
284 | ||
285 | cp = (u_char *)(ip + 1); | |
286 | dp = (u_char *)(jp + 1); | |
287 | cnt = (ip->ip_hl << 2) - sizeof (struct ip); | |
288 | for (; cnt > 0; cnt -= optlen, cp += optlen) { | |
289 | opt = cp[0]; | |
290 | if (opt == IPOPT_EOL) | |
291 | break; | |
292 | if (opt == IPOPT_NOP) | |
293 | optlen = 1; | |
294 | else | |
53ba4464 | 295 | optlen = cp[IPOPT_OLEN]; |
2b4b57cd BJ |
296 | if (optlen > cnt) /* XXX */ |
297 | optlen = cnt; /* XXX */ | |
298 | if (off == 0 || IPOPT_COPIED(opt)) { | |
4ad99bae | 299 | bcopy((caddr_t)cp, (caddr_t)dp, (unsigned)optlen); |
2b4b57cd | 300 | dp += optlen; |
ac904f92 | 301 | } |
e8d11875 | 302 | } |
2b4b57cd BJ |
303 | for (optlen = dp - (u_char *)(jp+1); optlen & 0x3; optlen++) |
304 | *dp++ = IPOPT_EOL; | |
305 | return (optlen); | |
ac904f92 | 306 | } |
53ba4464 MK |
307 | |
308 | /* | |
309 | * IP socket option processing. | |
310 | */ | |
311 | ip_ctloutput(op, so, level, optname, m) | |
312 | int op; | |
313 | struct socket *so; | |
314 | int level, optname; | |
315 | struct mbuf **m; | |
316 | { | |
317 | int error = 0; | |
318 | struct inpcb *inp = sotoinpcb(so); | |
319 | ||
320 | if (level != IPPROTO_IP) | |
321 | error = EINVAL; | |
322 | else switch (op) { | |
323 | ||
324 | case PRCO_SETOPT: | |
325 | switch (optname) { | |
326 | case IP_OPTIONS: | |
0c3fb1b4 | 327 | return (ip_pcbopts(&inp->inp_options, *m)); |
53ba4464 MK |
328 | |
329 | default: | |
330 | error = EINVAL; | |
331 | break; | |
332 | } | |
333 | break; | |
334 | ||
335 | case PRCO_GETOPT: | |
336 | switch (optname) { | |
337 | case IP_OPTIONS: | |
338 | *m = m_get(M_WAIT, MT_SOOPTS); | |
339 | if (inp->inp_options) { | |
340 | (*m)->m_off = inp->inp_options->m_off; | |
341 | (*m)->m_len = inp->inp_options->m_len; | |
342 | bcopy(mtod(inp->inp_options, caddr_t), | |
8011f5df | 343 | mtod(*m, caddr_t), (unsigned)(*m)->m_len); |
53ba4464 MK |
344 | } else |
345 | (*m)->m_len = 0; | |
346 | break; | |
347 | default: | |
348 | error = EINVAL; | |
349 | break; | |
350 | } | |
351 | break; | |
352 | } | |
85b035eb | 353 | if (op == PRCO_SETOPT && *m) |
8011f5df | 354 | (void)m_free(*m); |
53ba4464 MK |
355 | return (error); |
356 | } | |
357 | ||
358 | /* | |
0c3fb1b4 MK |
359 | * Set up IP options in pcb for insertion in output packets. |
360 | * Store in mbuf with pointer in pcbopt, adding pseudo-option | |
361 | * with destination address if source routed. | |
53ba4464 | 362 | */ |
0c3fb1b4 MK |
363 | ip_pcbopts(pcbopt, m) |
364 | struct mbuf **pcbopt; | |
365 | register struct mbuf *m; | |
53ba4464 MK |
366 | { |
367 | register cnt, optlen; | |
368 | register u_char *cp; | |
369 | u_char opt; | |
370 | ||
371 | /* turn off any old options */ | |
0c3fb1b4 | 372 | if (*pcbopt) |
8011f5df | 373 | (void)m_free(*pcbopt); |
0c3fb1b4 | 374 | *pcbopt = 0; |
53ba4464 MK |
375 | if (m == (struct mbuf *)0 || m->m_len == 0) { |
376 | /* | |
377 | * Only turning off any previous options. | |
378 | */ | |
379 | if (m) | |
8011f5df | 380 | (void)m_free(m); |
53ba4464 MK |
381 | return (0); |
382 | } | |
383 | ||
384 | #ifndef vax | |
385 | if (m->m_len % sizeof(long)) | |
386 | goto bad; | |
387 | #endif | |
388 | /* | |
389 | * IP first-hop destination address will be stored before | |
390 | * actual options; move other options back | |
391 | * and clear it when none present. | |
392 | */ | |
393 | #if MAX_IPOPTLEN >= MMAXOFF - MMINOFF | |
394 | if (m->m_off + m->m_len + sizeof(struct in_addr) > MAX_IPOPTLEN) | |
395 | goto bad; | |
396 | #else | |
397 | if (m->m_off + m->m_len + sizeof(struct in_addr) > MMAXOFF) | |
398 | goto bad; | |
399 | #endif | |
400 | cnt = m->m_len; | |
401 | m->m_len += sizeof(struct in_addr); | |
402 | cp = mtod(m, u_char *) + sizeof(struct in_addr); | |
8011f5df | 403 | ovbcopy(mtod(m, caddr_t), (caddr_t)cp, (unsigned)cnt); |
53ba4464 MK |
404 | bzero(mtod(m, caddr_t), sizeof(struct in_addr)); |
405 | ||
406 | for (; cnt > 0; cnt -= optlen, cp += optlen) { | |
407 | opt = cp[IPOPT_OPTVAL]; | |
408 | if (opt == IPOPT_EOL) | |
409 | break; | |
410 | if (opt == IPOPT_NOP) | |
411 | optlen = 1; | |
412 | else { | |
413 | optlen = cp[IPOPT_OLEN]; | |
414 | if (optlen <= IPOPT_OLEN || optlen > cnt) | |
415 | goto bad; | |
416 | } | |
417 | switch (opt) { | |
418 | ||
419 | default: | |
420 | break; | |
421 | ||
422 | case IPOPT_LSRR: | |
423 | case IPOPT_SSRR: | |
424 | /* | |
425 | * user process specifies route as: | |
426 | * ->A->B->C->D | |
427 | * D must be our final destination (but we can't | |
428 | * check that since we may not have connected yet). | |
429 | * A is first hop destination, which doesn't appear in | |
430 | * actual IP option, but is stored before the options. | |
431 | */ | |
432 | if (optlen < IPOPT_MINOFF - 1 + sizeof(struct in_addr)) | |
433 | goto bad; | |
434 | m->m_len -= sizeof(struct in_addr); | |
435 | cnt -= sizeof(struct in_addr); | |
436 | optlen -= sizeof(struct in_addr); | |
437 | cp[IPOPT_OLEN] = optlen; | |
438 | /* | |
439 | * Move first hop before start of options. | |
440 | */ | |
8011f5df | 441 | bcopy((caddr_t)&cp[IPOPT_OFFSET+1], mtod(m, caddr_t), |
53ba4464 MK |
442 | sizeof(struct in_addr)); |
443 | /* | |
444 | * Then copy rest of options back | |
445 | * to close up the deleted entry. | |
446 | */ | |
8011f5df MK |
447 | ovbcopy((caddr_t)(&cp[IPOPT_OFFSET+1] + |
448 | sizeof(struct in_addr)), | |
449 | (caddr_t)&cp[IPOPT_OFFSET+1], | |
450 | (unsigned)cnt + sizeof(struct in_addr)); | |
53ba4464 MK |
451 | break; |
452 | } | |
453 | } | |
0c3fb1b4 | 454 | *pcbopt = m; |
53ba4464 MK |
455 | return (0); |
456 | ||
457 | bad: | |
8011f5df | 458 | (void)m_free(m); |
53ba4464 MK |
459 | return (EINVAL); |
460 | } |