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15637ed4 RG |
1 | /* |
2 | * Copyright (c) 1982, 1986, 1988 Regents of the University of California. | |
3 | * All rights reserved. | |
4 | * | |
5 | * Redistribution and use in source and binary forms, with or without | |
6 | * modification, are permitted provided that the following conditions | |
7 | * are met: | |
8 | * 1. Redistributions of source code must retain the above copyright | |
9 | * notice, this list of conditions and the following disclaimer. | |
10 | * 2. Redistributions in binary form must reproduce the above copyright | |
11 | * notice, this list of conditions and the following disclaimer in the | |
12 | * documentation and/or other materials provided with the distribution. | |
13 | * 3. All advertising materials mentioning features or use of this software | |
14 | * must display the following acknowledgement: | |
15 | * This product includes software developed by the University of | |
16 | * California, Berkeley and its contributors. | |
17 | * 4. Neither the name of the University nor the names of its contributors | |
18 | * may be used to endorse or promote products derived from this software | |
19 | * without specific prior written permission. | |
20 | * | |
21 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND | |
22 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | |
23 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | |
24 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE | |
25 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL | |
26 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS | |
27 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) | |
28 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT | |
29 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY | |
30 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF | |
31 | * SUCH DAMAGE. | |
32 | * | |
33 | * @(#)if_ether.c 7.13 (Berkeley) 10/31/90 | |
34 | */ | |
35 | ||
36 | /* | |
37 | * Ethernet address resolution protocol. | |
38 | * TODO: | |
39 | * run at splnet (add ARP protocol intr.) | |
40 | * link entries onto hash chains, keep free list | |
41 | * add "inuse/lock" bit (or ref. count) along with valid bit | |
42 | */ | |
43 | ||
44 | #include "param.h" | |
45 | #include "systm.h" | |
46 | #include "malloc.h" | |
47 | #include "mbuf.h" | |
48 | #include "socket.h" | |
49 | #include "time.h" | |
50 | #include "kernel.h" | |
51 | #include "errno.h" | |
52 | #include "ioctl.h" | |
53 | #include "syslog.h" | |
54 | ||
55 | #include "../net/if.h" | |
56 | #include "in.h" | |
57 | #include "in_systm.h" | |
58 | #include "in_var.h" | |
59 | #include "ip.h" | |
60 | #include "if_ether.h" | |
61 | ||
62 | #ifdef GATEWAY | |
63 | #define ARPTAB_BSIZ 16 /* bucket size */ | |
64 | #define ARPTAB_NB 37 /* number of buckets */ | |
65 | #else | |
66 | #define ARPTAB_BSIZ 9 /* bucket size */ | |
67 | #define ARPTAB_NB 19 /* number of buckets */ | |
68 | #endif | |
69 | #define ARPTAB_SIZE (ARPTAB_BSIZ * ARPTAB_NB) | |
70 | struct arptab arptab[ARPTAB_SIZE]; | |
71 | int arptab_size = ARPTAB_SIZE; /* for arp command */ | |
72 | ||
73 | /* | |
74 | * ARP trailer negotiation. Trailer protocol is not IP specific, | |
75 | * but ARP request/response use IP addresses. | |
76 | */ | |
77 | #define ETHERTYPE_IPTRAILERS ETHERTYPE_TRAIL | |
78 | ||
79 | #define ARPTAB_HASH(a) \ | |
80 | ((u_long)(a) % ARPTAB_NB) | |
81 | ||
82 | #define ARPTAB_LOOK(at,addr) { \ | |
83 | register n; \ | |
84 | at = &arptab[ARPTAB_HASH(addr) * ARPTAB_BSIZ]; \ | |
85 | for (n = 0 ; n < ARPTAB_BSIZ ; n++,at++) \ | |
86 | if (at->at_iaddr.s_addr == addr) \ | |
87 | break; \ | |
88 | if (n >= ARPTAB_BSIZ) \ | |
89 | at = 0; \ | |
90 | } | |
91 | ||
92 | /* timer values */ | |
93 | #define ARPT_AGE (60*1) /* aging timer, 1 min. */ | |
94 | #define ARPT_KILLC 20 /* kill completed entry in 20 mins. */ | |
95 | #define ARPT_KILLI 3 /* kill incomplete entry in 3 minutes */ | |
96 | ||
97 | extern struct ifnet loif; | |
98 | ||
99 | /* | |
100 | * Timeout routine. Age arp_tab entries once a minute. | |
101 | */ | |
102 | arptimer() | |
103 | { | |
104 | register struct arptab *at; | |
105 | register i; | |
106 | ||
107 | timeout(arptimer, (caddr_t)0, ARPT_AGE * hz); | |
108 | at = &arptab[0]; | |
109 | for (i = 0; i < ARPTAB_SIZE; i++, at++) { | |
110 | if (at->at_flags == 0 || (at->at_flags & ATF_PERM)) | |
111 | continue; | |
112 | if (++at->at_timer < ((at->at_flags&ATF_COM) ? | |
113 | ARPT_KILLC : ARPT_KILLI)) | |
114 | continue; | |
115 | /* timer has expired, clear entry */ | |
116 | arptfree(at); | |
117 | } | |
118 | } | |
119 | ||
120 | /* | |
121 | * Broadcast an ARP packet, asking who has addr on interface ac. | |
122 | */ | |
123 | arpwhohas(ac, addr) | |
124 | register struct arpcom *ac; | |
125 | struct in_addr *addr; | |
126 | { | |
127 | register struct mbuf *m; | |
128 | register struct ether_header *eh; | |
129 | register struct ether_arp *ea; | |
130 | struct sockaddr sa; | |
131 | ||
132 | if ((m = m_gethdr(M_DONTWAIT, MT_DATA)) == NULL) | |
133 | return; | |
134 | m->m_len = sizeof(*ea); | |
135 | m->m_pkthdr.len = sizeof(*ea); | |
136 | MH_ALIGN(m, sizeof(*ea)); | |
137 | ea = mtod(m, struct ether_arp *); | |
138 | eh = (struct ether_header *)sa.sa_data; | |
139 | bzero((caddr_t)ea, sizeof (*ea)); | |
140 | bcopy((caddr_t)etherbroadcastaddr, (caddr_t)eh->ether_dhost, | |
141 | sizeof(eh->ether_dhost)); | |
142 | eh->ether_type = ETHERTYPE_ARP; /* if_output will swap */ | |
143 | ea->arp_hrd = htons(ARPHRD_ETHER); | |
144 | ea->arp_pro = htons(ETHERTYPE_IP); | |
145 | ea->arp_hln = sizeof(ea->arp_sha); /* hardware address length */ | |
146 | ea->arp_pln = sizeof(ea->arp_spa); /* protocol address length */ | |
147 | ea->arp_op = htons(ARPOP_REQUEST); | |
148 | bcopy((caddr_t)ac->ac_enaddr, (caddr_t)ea->arp_sha, | |
149 | sizeof(ea->arp_sha)); | |
150 | bcopy((caddr_t)&ac->ac_ipaddr, (caddr_t)ea->arp_spa, | |
151 | sizeof(ea->arp_spa)); | |
152 | bcopy((caddr_t)addr, (caddr_t)ea->arp_tpa, sizeof(ea->arp_tpa)); | |
153 | sa.sa_family = AF_UNSPEC; | |
154 | sa.sa_len = sizeof(sa); | |
155 | (*ac->ac_if.if_output)(&ac->ac_if, m, &sa, (struct rtentry *)0); | |
156 | } | |
157 | ||
158 | int useloopback = 1; /* use loopback interface for local traffic */ | |
159 | ||
160 | /* | |
161 | * Resolve an IP address into an ethernet address. If success, | |
162 | * desten is filled in. If there is no entry in arptab, | |
163 | * set one up and broadcast a request for the IP address. | |
164 | * Hold onto this mbuf and resend it once the address | |
165 | * is finally resolved. A return value of 1 indicates | |
166 | * that desten has been filled in and the packet should be sent | |
167 | * normally; a 0 return indicates that the packet has been | |
168 | * taken over here, either now or for later transmission. | |
169 | * | |
170 | * We do some (conservative) locking here at splimp, since | |
171 | * arptab is also altered from input interrupt service (ecintr/ilintr | |
172 | * calls arpinput when ETHERTYPE_ARP packets come in). | |
173 | */ | |
174 | arpresolve(ac, m, destip, desten, usetrailers) | |
175 | register struct arpcom *ac; | |
176 | struct mbuf *m; | |
177 | register struct in_addr *destip; | |
178 | register u_char *desten; | |
179 | int *usetrailers; | |
180 | { | |
181 | register struct arptab *at; | |
182 | struct sockaddr_in sin; | |
183 | register struct in_ifaddr *ia; | |
184 | u_long lna; | |
185 | int s; | |
186 | ||
187 | *usetrailers = 0; | |
188 | if (m->m_flags & M_BCAST) { /* broadcast */ | |
189 | bcopy((caddr_t)etherbroadcastaddr, (caddr_t)desten, | |
190 | sizeof(etherbroadcastaddr)); | |
191 | return (1); | |
192 | } | |
193 | lna = in_lnaof(*destip); | |
194 | /* if for us, use software loopback driver if up */ | |
195 | for (ia = in_ifaddr; ia; ia = ia->ia_next) | |
196 | if ((ia->ia_ifp == &ac->ac_if) && | |
197 | (destip->s_addr == ia->ia_addr.sin_addr.s_addr)) { | |
198 | /* | |
199 | * This test used to be | |
200 | * if (loif.if_flags & IFF_UP) | |
201 | * It allowed local traffic to be forced | |
202 | * through the hardware by configuring the loopback down. | |
203 | * However, it causes problems during network configuration | |
204 | * for boards that can't receive packets they send. | |
205 | * It is now necessary to clear "useloopback" | |
206 | * to force traffic out to the hardware. | |
207 | */ | |
208 | if (useloopback) { | |
209 | sin.sin_family = AF_INET; | |
210 | sin.sin_addr = *destip; | |
211 | (void) looutput(&loif, m, (struct sockaddr *)&sin, 0); | |
212 | /* | |
213 | * The packet has already been sent and freed. | |
214 | */ | |
215 | return (0); | |
216 | } else { | |
217 | bcopy((caddr_t)ac->ac_enaddr, (caddr_t)desten, | |
218 | sizeof(ac->ac_enaddr)); | |
219 | return (1); | |
220 | } | |
221 | } | |
222 | s = splimp(); | |
223 | ARPTAB_LOOK(at, destip->s_addr); | |
224 | if (at == 0) { /* not found */ | |
225 | if (ac->ac_if.if_flags & IFF_NOARP) { | |
226 | bcopy((caddr_t)ac->ac_enaddr, (caddr_t)desten, 3); | |
227 | desten[3] = (lna >> 16) & 0x7f; | |
228 | desten[4] = (lna >> 8) & 0xff; | |
229 | desten[5] = lna & 0xff; | |
230 | splx(s); | |
231 | return (1); | |
232 | } else { | |
233 | at = arptnew(destip); | |
234 | if (at == 0) | |
235 | panic("arpresolve: no free entry"); | |
236 | at->at_hold = m; | |
237 | arpwhohas(ac, destip); | |
238 | splx(s); | |
239 | return (0); | |
240 | } | |
241 | } | |
242 | at->at_timer = 0; /* restart the timer */ | |
243 | if (at->at_flags & ATF_COM) { /* entry IS complete */ | |
47110967 RG |
244 | |
245 | *(int *) desten = *(int *) at->at_enaddr; | |
246 | ((short *) desten)[2] = ((short *) at->at_enaddr)[2]; | |
247 | ||
15637ed4 RG |
248 | if (at->at_flags & ATF_USETRAILERS) |
249 | *usetrailers = 1; | |
250 | splx(s); | |
251 | return (1); | |
252 | } | |
253 | /* | |
254 | * There is an arptab entry, but no ethernet address | |
255 | * response yet. Replace the held mbuf with this | |
256 | * latest one. | |
257 | */ | |
258 | if (at->at_hold) | |
259 | m_freem(at->at_hold); | |
260 | at->at_hold = m; | |
261 | arpwhohas(ac, destip); /* ask again */ | |
262 | splx(s); | |
263 | return (0); | |
264 | } | |
265 | ||
266 | /* | |
267 | * Called from 10 Mb/s Ethernet interrupt handlers | |
268 | * when ether packet type ETHERTYPE_ARP | |
269 | * is received. Common length and type checks are done here, | |
270 | * then the protocol-specific routine is called. | |
271 | */ | |
272 | arpinput(ac, m) | |
273 | struct arpcom *ac; | |
274 | struct mbuf *m; | |
275 | { | |
276 | register struct arphdr *ar; | |
277 | ||
278 | if (ac->ac_if.if_flags & IFF_NOARP) | |
279 | goto out; | |
280 | if (m->m_len < sizeof(struct arphdr)) | |
281 | goto out; | |
282 | ar = mtod(m, struct arphdr *); | |
283 | if (ntohs(ar->ar_hrd) != ARPHRD_ETHER) | |
284 | goto out; | |
285 | if (m->m_len < sizeof(struct arphdr) + 2 * ar->ar_hln + 2 * ar->ar_pln) | |
286 | goto out; | |
287 | ||
288 | switch (ntohs(ar->ar_pro)) { | |
289 | ||
290 | case ETHERTYPE_IP: | |
291 | case ETHERTYPE_IPTRAILERS: | |
292 | in_arpinput(ac, m); | |
293 | return; | |
294 | ||
295 | default: | |
296 | break; | |
297 | } | |
298 | out: | |
299 | m_freem(m); | |
300 | } | |
301 | ||
302 | /* | |
303 | * ARP for Internet protocols on 10 Mb/s Ethernet. | |
304 | * Algorithm is that given in RFC 826. | |
305 | * In addition, a sanity check is performed on the sender | |
306 | * protocol address, to catch impersonators. | |
307 | * We also handle negotiations for use of trailer protocol: | |
308 | * ARP replies for protocol type ETHERTYPE_TRAIL are sent | |
309 | * along with IP replies if we want trailers sent to us, | |
310 | * and also send them in response to IP replies. | |
311 | * This allows either end to announce the desire to receive | |
312 | * trailer packets. | |
313 | * We reply to requests for ETHERTYPE_TRAIL protocol as well, | |
314 | * but don't normally send requests. | |
315 | */ | |
316 | in_arpinput(ac, m) | |
317 | register struct arpcom *ac; | |
318 | struct mbuf *m; | |
319 | { | |
320 | register struct ether_arp *ea; | |
321 | struct ether_header *eh; | |
322 | register struct arptab *at; /* same as "merge" flag */ | |
323 | register struct in_ifaddr *ia; | |
324 | struct in_ifaddr *maybe_ia = 0; | |
325 | struct mbuf *mcopy = 0; | |
326 | struct sockaddr_in sin; | |
327 | struct sockaddr sa; | |
328 | struct in_addr isaddr, itaddr, myaddr; | |
329 | int proto, op, s, completed = 0; | |
330 | ||
331 | ea = mtod(m, struct ether_arp *); | |
332 | proto = ntohs(ea->arp_pro); | |
333 | op = ntohs(ea->arp_op); | |
334 | bcopy((caddr_t)ea->arp_spa, (caddr_t)&isaddr, sizeof (isaddr)); | |
335 | bcopy((caddr_t)ea->arp_tpa, (caddr_t)&itaddr, sizeof (itaddr)); | |
336 | for (ia = in_ifaddr; ia; ia = ia->ia_next) | |
337 | if (ia->ia_ifp == &ac->ac_if) { | |
338 | maybe_ia = ia; | |
339 | if ((itaddr.s_addr == ia->ia_addr.sin_addr.s_addr) || | |
340 | (isaddr.s_addr == ia->ia_addr.sin_addr.s_addr)) | |
341 | break; | |
342 | } | |
343 | if (maybe_ia == 0) | |
344 | goto out; | |
345 | myaddr = ia ? ia->ia_addr.sin_addr : maybe_ia->ia_addr.sin_addr; | |
346 | if (!bcmp((caddr_t)ea->arp_sha, (caddr_t)ac->ac_enaddr, | |
347 | sizeof (ea->arp_sha))) | |
348 | goto out; /* it's from me, ignore it. */ | |
349 | if (!bcmp((caddr_t)ea->arp_sha, (caddr_t)etherbroadcastaddr, | |
350 | sizeof (ea->arp_sha))) { | |
351 | log(LOG_ERR, | |
352 | "arp: ether address is broadcast for IP address %x!\n", | |
353 | ntohl(isaddr.s_addr)); | |
354 | goto out; | |
355 | } | |
356 | if (isaddr.s_addr == myaddr.s_addr) { | |
357 | log(LOG_ERR, | |
358 | "duplicate IP address %x!! sent from ethernet address: %s\n", | |
359 | ntohl(isaddr.s_addr), ether_sprintf(ea->arp_sha)); | |
360 | itaddr = myaddr; | |
361 | if (op == ARPOP_REQUEST) | |
362 | goto reply; | |
363 | goto out; | |
364 | } | |
365 | s = splimp(); | |
366 | ARPTAB_LOOK(at, isaddr.s_addr); | |
367 | if (at) { | |
368 | bcopy((caddr_t)ea->arp_sha, (caddr_t)at->at_enaddr, | |
369 | sizeof(ea->arp_sha)); | |
370 | if ((at->at_flags & ATF_COM) == 0) | |
371 | completed = 1; | |
372 | at->at_flags |= ATF_COM; | |
373 | if (at->at_hold) { | |
374 | sin.sin_family = AF_INET; | |
375 | sin.sin_addr = isaddr; | |
376 | (*ac->ac_if.if_output)(&ac->ac_if, at->at_hold, | |
377 | (struct sockaddr *)&sin, (struct rtentry *)0); | |
378 | at->at_hold = 0; | |
379 | } | |
380 | } | |
381 | if (at == 0 && itaddr.s_addr == myaddr.s_addr) { | |
382 | /* ensure we have a table entry */ | |
383 | if (at = arptnew(&isaddr)) { | |
384 | bcopy((caddr_t)ea->arp_sha, (caddr_t)at->at_enaddr, | |
385 | sizeof(ea->arp_sha)); | |
386 | completed = 1; | |
387 | at->at_flags |= ATF_COM; | |
388 | } | |
389 | } | |
390 | splx(s); | |
391 | reply: | |
392 | switch (proto) { | |
393 | ||
394 | case ETHERTYPE_IPTRAILERS: | |
395 | /* partner says trailers are OK */ | |
396 | if (at) | |
397 | at->at_flags |= ATF_USETRAILERS; | |
398 | /* | |
399 | * Reply to request iff we want trailers. | |
400 | */ | |
401 | if (op != ARPOP_REQUEST || ac->ac_if.if_flags & IFF_NOTRAILERS) | |
402 | goto out; | |
403 | break; | |
404 | ||
405 | case ETHERTYPE_IP: | |
406 | /* | |
407 | * Reply if this is an IP request, | |
408 | * or if we want to send a trailer response. | |
409 | * Send the latter only to the IP response | |
410 | * that completes the current ARP entry. | |
411 | */ | |
412 | if (op != ARPOP_REQUEST && | |
413 | (completed == 0 || ac->ac_if.if_flags & IFF_NOTRAILERS)) | |
414 | goto out; | |
415 | } | |
416 | if (itaddr.s_addr == myaddr.s_addr) { | |
417 | /* I am the target */ | |
418 | bcopy((caddr_t)ea->arp_sha, (caddr_t)ea->arp_tha, | |
419 | sizeof(ea->arp_sha)); | |
420 | bcopy((caddr_t)ac->ac_enaddr, (caddr_t)ea->arp_sha, | |
421 | sizeof(ea->arp_sha)); | |
422 | } else { | |
423 | ARPTAB_LOOK(at, itaddr.s_addr); | |
424 | if (at == NULL || (at->at_flags & ATF_PUBL) == 0) | |
425 | goto out; | |
426 | bcopy((caddr_t)ea->arp_sha, (caddr_t)ea->arp_tha, | |
427 | sizeof(ea->arp_sha)); | |
428 | bcopy((caddr_t)at->at_enaddr, (caddr_t)ea->arp_sha, | |
429 | sizeof(ea->arp_sha)); | |
430 | } | |
431 | ||
432 | bcopy((caddr_t)ea->arp_spa, (caddr_t)ea->arp_tpa, | |
433 | sizeof(ea->arp_spa)); | |
434 | bcopy((caddr_t)&itaddr, (caddr_t)ea->arp_spa, | |
435 | sizeof(ea->arp_spa)); | |
436 | ea->arp_op = htons(ARPOP_REPLY); | |
437 | /* | |
438 | * If incoming packet was an IP reply, | |
439 | * we are sending a reply for type IPTRAILERS. | |
440 | * If we are sending a reply for type IP | |
441 | * and we want to receive trailers, | |
442 | * send a trailer reply as well. | |
443 | */ | |
444 | if (op == ARPOP_REPLY) | |
445 | ea->arp_pro = htons(ETHERTYPE_IPTRAILERS); | |
446 | else if (proto == ETHERTYPE_IP && | |
447 | (ac->ac_if.if_flags & IFF_NOTRAILERS) == 0) | |
448 | mcopy = m_copy(m, 0, (int)M_COPYALL); | |
449 | eh = (struct ether_header *)sa.sa_data; | |
450 | bcopy((caddr_t)ea->arp_tha, (caddr_t)eh->ether_dhost, | |
451 | sizeof(eh->ether_dhost)); | |
452 | eh->ether_type = ETHERTYPE_ARP; | |
453 | sa.sa_family = AF_UNSPEC; | |
454 | sa.sa_len = sizeof(sa); | |
455 | (*ac->ac_if.if_output)(&ac->ac_if, m, &sa, (struct rtentry *)0); | |
456 | if (mcopy) { | |
457 | ea = mtod(mcopy, struct ether_arp *); | |
458 | ea->arp_pro = htons(ETHERTYPE_IPTRAILERS); | |
459 | (*ac->ac_if.if_output)(&ac->ac_if, | |
460 | mcopy, &sa, (struct rtentry *)0); | |
461 | } | |
462 | return; | |
463 | out: | |
464 | m_freem(m); | |
465 | return; | |
466 | } | |
467 | ||
468 | /* | |
469 | * Free an arptab entry. | |
470 | */ | |
471 | arptfree(at) | |
472 | register struct arptab *at; | |
473 | { | |
474 | int s = splimp(); | |
475 | ||
476 | if (at->at_hold) | |
477 | m_freem(at->at_hold); | |
478 | at->at_hold = 0; | |
479 | at->at_timer = at->at_flags = 0; | |
480 | at->at_iaddr.s_addr = 0; | |
481 | splx(s); | |
482 | } | |
483 | ||
484 | /* | |
485 | * Enter a new address in arptab, pushing out the oldest entry | |
486 | * from the bucket if there is no room. | |
487 | * This always succeeds since no bucket can be completely filled | |
488 | * with permanent entries (except from arpioctl when testing whether | |
489 | * another permanent entry will fit). | |
490 | * MUST BE CALLED AT SPLIMP. | |
491 | */ | |
492 | struct arptab * | |
493 | arptnew(addr) | |
494 | struct in_addr *addr; | |
495 | { | |
496 | register n; | |
497 | int oldest = -1; | |
498 | register struct arptab *at, *ato = NULL; | |
499 | static int first = 1; | |
500 | ||
501 | if (first) { | |
502 | first = 0; | |
503 | timeout(arptimer, (caddr_t)0, hz); | |
504 | } | |
505 | at = &arptab[ARPTAB_HASH(addr->s_addr) * ARPTAB_BSIZ]; | |
506 | for (n = 0; n < ARPTAB_BSIZ; n++,at++) { | |
507 | if (at->at_flags == 0) | |
508 | goto out; /* found an empty entry */ | |
509 | if (at->at_flags & ATF_PERM) | |
510 | continue; | |
511 | if ((int) at->at_timer > oldest) { | |
512 | oldest = at->at_timer; | |
513 | ato = at; | |
514 | } | |
515 | } | |
516 | if (ato == NULL) | |
517 | return (NULL); | |
518 | at = ato; | |
519 | arptfree(at); | |
520 | out: | |
521 | at->at_iaddr = *addr; | |
522 | at->at_flags = ATF_INUSE; | |
523 | return (at); | |
524 | } | |
525 | ||
526 | arpioctl(cmd, data) | |
527 | int cmd; | |
528 | caddr_t data; | |
529 | { | |
530 | register struct arpreq *ar = (struct arpreq *)data; | |
531 | register struct arptab *at; | |
532 | register struct sockaddr_in *sin; | |
533 | int s; | |
534 | ||
535 | sin = (struct sockaddr_in *)&ar->arp_ha; | |
536 | #if defined(COMPAT_43) && BYTE_ORDER != BIG_ENDIAN | |
537 | if (sin->sin_family == 0 && sin->sin_len < 16) | |
538 | sin->sin_family = sin->sin_len; | |
539 | #endif | |
540 | sin->sin_len = sizeof(ar->arp_ha); | |
541 | sin = (struct sockaddr_in *)&ar->arp_pa; | |
542 | #if defined(COMPAT_43) && BYTE_ORDER != BIG_ENDIAN | |
543 | if (sin->sin_family == 0 && sin->sin_len < 16) | |
544 | sin->sin_family = sin->sin_len; | |
545 | #endif | |
546 | sin->sin_len = sizeof(ar->arp_pa); | |
547 | if (ar->arp_pa.sa_family != AF_INET || | |
548 | ar->arp_ha.sa_family != AF_UNSPEC) | |
549 | return (EAFNOSUPPORT); | |
550 | s = splimp(); | |
551 | ARPTAB_LOOK(at, sin->sin_addr.s_addr); | |
552 | if (at == NULL) { /* not found */ | |
553 | if (cmd != SIOCSARP) { | |
554 | splx(s); | |
555 | return (ENXIO); | |
556 | } | |
557 | if (ifa_ifwithnet(&ar->arp_pa) == NULL) { | |
558 | splx(s); | |
559 | return (ENETUNREACH); | |
560 | } | |
561 | } | |
562 | switch (cmd) { | |
563 | ||
564 | case SIOCSARP: /* set entry */ | |
565 | if (at == NULL) { | |
566 | at = arptnew(&sin->sin_addr); | |
567 | if (at == NULL) { | |
568 | splx(s); | |
569 | return (EADDRNOTAVAIL); | |
570 | } | |
571 | if (ar->arp_flags & ATF_PERM) { | |
572 | /* never make all entries in a bucket permanent */ | |
573 | register struct arptab *tat; | |
574 | ||
575 | /* try to re-allocate */ | |
576 | tat = arptnew(&sin->sin_addr); | |
577 | if (tat == NULL) { | |
578 | arptfree(at); | |
579 | splx(s); | |
580 | return (EADDRNOTAVAIL); | |
581 | } | |
582 | arptfree(tat); | |
583 | } | |
584 | } | |
585 | bcopy((caddr_t)ar->arp_ha.sa_data, (caddr_t)at->at_enaddr, | |
586 | sizeof(at->at_enaddr)); | |
587 | at->at_flags = ATF_COM | ATF_INUSE | | |
588 | (ar->arp_flags & (ATF_PERM|ATF_PUBL|ATF_USETRAILERS)); | |
589 | at->at_timer = 0; | |
590 | break; | |
591 | ||
592 | case SIOCDARP: /* delete entry */ | |
593 | arptfree(at); | |
594 | break; | |
595 | ||
596 | case SIOCGARP: /* get entry */ | |
597 | case OSIOCGARP: | |
598 | bcopy((caddr_t)at->at_enaddr, (caddr_t)ar->arp_ha.sa_data, | |
599 | sizeof(at->at_enaddr)); | |
600 | #ifdef COMPAT_43 | |
601 | if (cmd == OSIOCGARP) | |
602 | *(u_short *)&ar->arp_ha = ar->arp_ha.sa_family; | |
603 | #endif | |
604 | ar->arp_flags = at->at_flags; | |
605 | break; | |
606 | } | |
607 | splx(s); | |
608 | return (0); | |
609 | } |