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aba5acdf SH |
1 | /* |
2 | * arpd.c ARP helper daemon. | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or | |
5 | * modify it under the terms of the GNU General Public License | |
6 | * as published by the Free Software Foundation; either version | |
7 | * 2 of the License, or (at your option) any later version. | |
8 | * | |
9 | * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> | |
10 | */ | |
11 | ||
12 | #include <stdio.h> | |
13 | #include <syslog.h> | |
14 | #include <malloc.h> | |
15 | #include <string.h> | |
16 | #include <unistd.h> | |
17 | #include <stdlib.h> | |
18 | #include <netdb.h> | |
16efac57 | 19 | #include <db_185.h> |
aba5acdf SH |
20 | #include <sys/ioctl.h> |
21 | #include <sys/poll.h> | |
22 | #include <errno.h> | |
23 | #include <fcntl.h> | |
24 | #include <sys/uio.h> | |
25 | #include <sys/socket.h> | |
26 | #include <sys/time.h> | |
27 | #include <time.h> | |
28 | #include <signal.h> | |
29 | #include <linux/if.h> | |
17ce7fd5 | 30 | #include <linux/if_ether.h> |
aba5acdf SH |
31 | #include <linux/if_arp.h> |
32 | #include <netinet/in.h> | |
33 | #include <arpa/inet.h> | |
34 | #include <linux/if_packet.h> | |
35 | #include <linux/filter.h> | |
36 | ||
37 | #include "libnetlink.h" | |
38 | #include "utils.h" | |
39 | ||
40 | int resolve_hosts; | |
41 | ||
42 | DB *dbase; | |
43 | char *dbname = "/var/lib/arpd/arpd.db"; | |
44 | ||
45 | int ifnum; | |
46 | int *ifvec; | |
47 | char **ifnames; | |
48 | ||
49 | struct dbkey | |
50 | { | |
51 | __u32 iface; | |
52 | __u32 addr; | |
53 | }; | |
54 | ||
55 | #define IS_NEG(x) (((__u8*)(x))[0] == 0xFF) | |
56 | #define NEG_TIME(x) (((x)[2]<<24)|((x)[3]<<16)|((x)[4]<<8)|(x)[5]) | |
57 | #define NEG_AGE(x) ((__u32)time(NULL) - NEG_TIME((__u8*)x)) | |
58 | #define NEG_VALID(x) (NEG_AGE(x) < negative_timeout) | |
59 | #define NEG_CNT(x) (((__u8*)(x))[1]) | |
60 | ||
61 | struct rtnl_handle rth; | |
62 | ||
63 | struct pollfd pset[2]; | |
64 | int udp_sock = -1; | |
65 | ||
66 | volatile int do_exit; | |
67 | volatile int do_sync; | |
68 | volatile int do_stats; | |
69 | ||
70 | struct { | |
71 | unsigned long arp_new; | |
72 | unsigned long arp_change; | |
73 | ||
74 | unsigned long app_recv; | |
75 | unsigned long app_success; | |
76 | unsigned long app_bad; | |
77 | unsigned long app_neg; | |
78 | unsigned long app_suppressed; | |
79 | ||
80 | unsigned long kern_neg; | |
81 | unsigned long kern_new; | |
82 | unsigned long kern_change; | |
83 | ||
84 | unsigned long probes_sent; | |
85 | unsigned long probes_suppressed; | |
86 | } stats; | |
87 | ||
88 | int active_probing; | |
89 | int negative_timeout = 60; | |
90 | int no_kernel_broadcasts; | |
91 | int broadcast_rate = 1000; | |
92 | int broadcast_burst = 3000; | |
93 | ||
94 | void usage(void) | |
95 | { | |
96 | fprintf(stderr, | |
97 | "Usage: arpd [ -lk ] [ -a N ] [ -b dbase ] [ -f file ] [ interfaces ]\n"); | |
98 | exit(1); | |
99 | } | |
100 | ||
101 | int handle_if(int ifindex) | |
102 | { | |
103 | int i; | |
104 | ||
105 | if (ifnum == 0) | |
106 | return 1; | |
107 | ||
108 | for (i=0; i<ifnum; i++) | |
109 | if (ifvec[i] == ifindex) | |
110 | return 1; | |
111 | return 0; | |
112 | } | |
113 | ||
114 | int sysctl_adjusted; | |
115 | ||
116 | void do_sysctl_adjustments(void) | |
117 | { | |
118 | int i; | |
119 | ||
120 | if (!ifnum) | |
121 | return; | |
122 | ||
123 | for (i=0; i<ifnum; i++) { | |
124 | char buf[128]; | |
125 | FILE *fp; | |
126 | ||
127 | if (active_probing) { | |
128 | sprintf(buf, "/proc/sys/net/ipv4/neigh/%s/mcast_solicit", ifnames[i]); | |
129 | if ((fp = fopen(buf, "w")) != NULL) { | |
130 | if (no_kernel_broadcasts) | |
131 | strcpy(buf, "0\n"); | |
132 | else | |
133 | sprintf(buf, "%d\n", active_probing>=2 ? 1 : 3-active_probing); | |
134 | fputs(buf, fp); | |
135 | fclose(fp); | |
136 | } | |
137 | } | |
138 | ||
139 | sprintf(buf, "/proc/sys/net/ipv4/neigh/%s/app_solicit", ifnames[i]); | |
140 | if ((fp = fopen(buf, "w")) != NULL) { | |
141 | sprintf(buf, "%d\n", active_probing<=1 ? 1 : active_probing); | |
142 | fputs(buf, fp); | |
143 | fclose(fp); | |
144 | } | |
145 | } | |
146 | sysctl_adjusted = 1; | |
147 | } | |
148 | ||
149 | void undo_sysctl_adjustments(void) | |
150 | { | |
151 | int i; | |
152 | ||
153 | if (!sysctl_adjusted) | |
154 | return; | |
155 | ||
156 | for (i=0; i<ifnum; i++) { | |
157 | char buf[128]; | |
158 | FILE *fp; | |
159 | ||
160 | if (active_probing) { | |
161 | sprintf(buf, "/proc/sys/net/ipv4/neigh/%s/mcast_solicit", ifnames[i]); | |
162 | if ((fp = fopen(buf, "w")) != NULL) { | |
163 | strcpy(buf, "3\n"); | |
164 | fputs(buf, fp); | |
165 | fclose(fp); | |
166 | } | |
167 | } | |
168 | sprintf(buf, "/proc/sys/net/ipv4/neigh/%s/app_solicit", ifnames[i]); | |
169 | if ((fp = fopen(buf, "w")) != NULL) { | |
170 | strcpy(buf, "0\n"); | |
171 | fputs(buf, fp); | |
172 | fclose(fp); | |
173 | } | |
174 | } | |
175 | sysctl_adjusted = 0; | |
176 | } | |
177 | ||
178 | ||
179 | int send_probe(int ifindex, __u32 addr) | |
180 | { | |
181 | struct ifreq ifr; | |
182 | struct sockaddr_in dst; | |
f332d169 | 183 | socklen_t len; |
aba5acdf SH |
184 | unsigned char buf[256]; |
185 | struct arphdr *ah = (struct arphdr*)buf; | |
186 | unsigned char *p = (unsigned char *)(ah+1); | |
187 | struct sockaddr_ll sll; | |
188 | ||
189 | memset(&ifr, 0, sizeof(ifr)); | |
190 | ifr.ifr_ifindex = ifindex; | |
191 | if (ioctl(udp_sock, SIOCGIFNAME, &ifr)) | |
192 | return -1; | |
193 | if (ioctl(udp_sock, SIOCGIFHWADDR, &ifr)) | |
194 | return -1; | |
195 | if (ifr.ifr_hwaddr.sa_family != ARPHRD_ETHER) | |
196 | return -1; | |
197 | if (setsockopt(udp_sock, SOL_SOCKET, SO_BINDTODEVICE, ifr.ifr_name, strlen(ifr.ifr_name)+1) < 0) | |
198 | return -1; | |
199 | ||
200 | dst.sin_family = AF_INET; | |
201 | dst.sin_port = htons(1025); | |
202 | dst.sin_addr.s_addr = addr; | |
203 | if (connect(udp_sock, (struct sockaddr*)&dst, sizeof(dst)) < 0) | |
204 | return -1; | |
205 | len = sizeof(dst); | |
206 | if (getsockname(udp_sock, (struct sockaddr*)&dst, &len) < 0) | |
207 | return -1; | |
208 | ||
209 | ah->ar_hrd = htons(ifr.ifr_hwaddr.sa_family); | |
210 | ah->ar_pro = htons(ETH_P_IP); | |
211 | ah->ar_hln = 6; | |
212 | ah->ar_pln = 4; | |
213 | ah->ar_op = htons(ARPOP_REQUEST); | |
214 | ||
215 | memcpy(p, ifr.ifr_hwaddr.sa_data, ah->ar_hln); | |
216 | p += ah->ar_hln; | |
217 | ||
218 | memcpy(p, &dst.sin_addr, 4); | |
219 | p+=4; | |
220 | ||
221 | sll.sll_family = AF_PACKET; | |
222 | memset(sll.sll_addr, 0xFF, sizeof(sll.sll_addr)); | |
223 | sll.sll_ifindex = ifindex; | |
224 | sll.sll_protocol = htons(ETH_P_ARP); | |
225 | memcpy(p, &sll.sll_addr, ah->ar_hln); | |
226 | p+=ah->ar_hln; | |
227 | ||
228 | memcpy(p, &addr, 4); | |
229 | p+=4; | |
230 | ||
f332d169 | 231 | if (sendto(pset[0].fd, buf, p-buf, 0, (struct sockaddr*)&sll, sizeof(sll)) < 0) |
aba5acdf SH |
232 | return -1; |
233 | stats.probes_sent++; | |
234 | return 0; | |
235 | } | |
236 | ||
237 | /* Be very tough on sending probes: 1 per second with burst of 3. */ | |
238 | ||
239 | int queue_active_probe(int ifindex, __u32 addr) | |
240 | { | |
241 | static struct timeval prev; | |
242 | static int buckets; | |
243 | struct timeval now; | |
244 | ||
245 | gettimeofday(&now, NULL); | |
246 | if (prev.tv_sec) { | |
247 | int diff = (now.tv_sec-prev.tv_sec)*1000+(now.tv_usec-prev.tv_usec)/1000; | |
248 | buckets += diff; | |
249 | } else { | |
250 | buckets = broadcast_burst; | |
251 | } | |
252 | if (buckets > broadcast_burst) | |
253 | buckets = broadcast_burst; | |
254 | if (buckets >= broadcast_rate && !send_probe(ifindex, addr)) { | |
255 | buckets -= broadcast_rate; | |
256 | prev = now; | |
257 | return 0; | |
258 | } | |
259 | stats.probes_suppressed++; | |
260 | return -1; | |
261 | } | |
262 | ||
263 | int respond_to_kernel(int ifindex, __u32 addr, char *lla, int llalen) | |
264 | { | |
265 | struct { | |
266 | struct nlmsghdr n; | |
267 | struct ndmsg ndm; | |
268 | char buf[256]; | |
269 | } req; | |
270 | ||
271 | memset(&req.n, 0, sizeof(req.n)); | |
272 | memset(&req.ndm, 0, sizeof(req.ndm)); | |
273 | ||
274 | req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct ndmsg)); | |
275 | req.n.nlmsg_flags = NLM_F_REQUEST; | |
276 | req.n.nlmsg_type = RTM_NEWNEIGH; | |
277 | req.ndm.ndm_family = AF_INET; | |
278 | req.ndm.ndm_state = NUD_STALE; | |
279 | req.ndm.ndm_ifindex = ifindex; | |
280 | req.ndm.ndm_type = RTN_UNICAST; | |
281 | ||
282 | addattr_l(&req.n, sizeof(req), NDA_DST, &addr, 4); | |
283 | addattr_l(&req.n, sizeof(req), NDA_LLADDR, lla, llalen); | |
284 | return rtnl_send(&rth, (char*)&req, req.n.nlmsg_len) <= 0; | |
285 | } | |
286 | ||
287 | void prepare_neg_entry(__u8 *ndata, __u32 stamp) | |
288 | { | |
289 | ndata[0] = 0xFF; | |
290 | ndata[1] = 0; | |
291 | ndata[2] = stamp>>24; | |
292 | ndata[3] = stamp>>16; | |
293 | ndata[4] = stamp>>8; | |
294 | ndata[5] = stamp; | |
295 | } | |
296 | ||
297 | ||
298 | int do_one_request(struct nlmsghdr *n) | |
299 | { | |
300 | struct ndmsg *ndm = NLMSG_DATA(n); | |
301 | int len = n->nlmsg_len; | |
302 | struct rtattr * tb[NDA_MAX+1]; | |
303 | struct dbkey key; | |
304 | DBT dbkey, dbdat; | |
305 | int do_acct = 0; | |
306 | ||
307 | if (n->nlmsg_type == NLMSG_DONE) { | |
308 | dbase->sync(dbase, 0); | |
309 | ||
310 | /* Now we have at least mirror of kernel db, so that | |
311 | * may start real resolution. | |
312 | */ | |
313 | do_sysctl_adjustments(); | |
314 | return 0; | |
315 | } | |
316 | ||
317 | if (n->nlmsg_type != RTM_GETNEIGH && n->nlmsg_type != RTM_NEWNEIGH) | |
318 | return 0; | |
319 | ||
320 | len -= NLMSG_LENGTH(sizeof(*ndm)); | |
321 | if (len < 0) | |
322 | return -1; | |
323 | ||
324 | if (ndm->ndm_family != AF_INET || | |
325 | (ifnum && !handle_if(ndm->ndm_ifindex)) || | |
326 | ndm->ndm_flags || | |
327 | ndm->ndm_type != RTN_UNICAST || | |
328 | !(ndm->ndm_state&~NUD_NOARP)) | |
329 | return 0; | |
330 | ||
aba5acdf SH |
331 | parse_rtattr(tb, NDA_MAX, NDA_RTA(ndm), len); |
332 | ||
333 | if (!tb[NDA_DST]) | |
334 | return 0; | |
335 | ||
336 | key.iface = ndm->ndm_ifindex; | |
337 | memcpy(&key.addr, RTA_DATA(tb[NDA_DST]), 4); | |
338 | dbkey.data = &key; | |
339 | dbkey.size = sizeof(key); | |
340 | ||
341 | if (dbase->get(dbase, &dbkey, &dbdat, 0) != 0) { | |
342 | dbdat.data = 0; | |
343 | dbdat.size = 0; | |
344 | } | |
345 | ||
346 | if (n->nlmsg_type == RTM_GETNEIGH) { | |
347 | if (!(n->nlmsg_flags&NLM_F_REQUEST)) | |
348 | return 0; | |
349 | ||
350 | if (!(ndm->ndm_state&(NUD_PROBE|NUD_INCOMPLETE))) { | |
351 | stats.app_bad++; | |
352 | return 0; | |
353 | } | |
354 | ||
355 | if (ndm->ndm_state&NUD_PROBE) { | |
356 | /* If we get this, kernel still has some valid | |
357 | * address, but unicast probing failed and host | |
358 | * is either dead or changed its mac address. | |
359 | * Kernel is going to initiate broadcast resolution. | |
360 | * OK, we invalidate our information as well. | |
361 | */ | |
362 | if (dbdat.data && !IS_NEG(dbdat.data)) | |
363 | stats.app_neg++; | |
364 | ||
365 | dbase->del(dbase, &dbkey, 0); | |
366 | } else { | |
367 | /* If we get this kernel does not have any information. | |
368 | * If we have something tell this to kernel. */ | |
369 | stats.app_recv++; | |
370 | if (dbdat.data && !IS_NEG(dbdat.data)) { | |
371 | stats.app_success++; | |
372 | respond_to_kernel(key.iface, key.addr, dbdat.data, dbdat.size); | |
373 | return 0; | |
374 | } | |
375 | ||
376 | /* Sheeit! We have nothing to tell. */ | |
377 | /* If we have recent negative entry, be silent. */ | |
378 | if (dbdat.data && NEG_VALID(dbdat.data)) { | |
379 | if (NEG_CNT(dbdat.data) >= active_probing) { | |
380 | stats.app_suppressed++; | |
381 | return 0; | |
382 | } | |
383 | do_acct = 1; | |
384 | } | |
385 | } | |
386 | ||
387 | if (active_probing && | |
388 | queue_active_probe(ndm->ndm_ifindex, key.addr) == 0 && | |
389 | do_acct) { | |
390 | NEG_CNT(dbdat.data)++; | |
391 | dbase->put(dbase, &dbkey, &dbdat, 0); | |
392 | } | |
393 | } else if (n->nlmsg_type == RTM_NEWNEIGH) { | |
394 | if (n->nlmsg_flags&NLM_F_REQUEST) | |
395 | return 0; | |
396 | ||
397 | if (ndm->ndm_state&NUD_FAILED) { | |
398 | /* Kernel was not able to resolve. Host is dead. | |
399 | * Create negative entry if it is not present | |
400 | * or renew it if it is too old. */ | |
401 | if (!dbdat.data || | |
402 | !IS_NEG(dbdat.data) || | |
403 | !NEG_VALID(dbdat.data)) { | |
404 | __u8 ndata[6]; | |
405 | stats.kern_neg++; | |
406 | prepare_neg_entry(ndata, time(NULL)); | |
407 | dbdat.data = ndata; | |
408 | dbdat.size = sizeof(ndata); | |
409 | dbase->put(dbase, &dbkey, &dbdat, 0); | |
410 | } | |
411 | } else if (tb[NDA_LLADDR]) { | |
412 | if (dbdat.data && !IS_NEG(dbdat.data)) { | |
413 | if (memcmp(RTA_DATA(tb[NDA_LLADDR]), dbdat.data, dbdat.size) == 0) | |
414 | return 0; | |
415 | stats.kern_change++; | |
416 | } else { | |
417 | stats.kern_new++; | |
418 | } | |
419 | dbdat.data = RTA_DATA(tb[NDA_LLADDR]); | |
420 | dbdat.size = RTA_PAYLOAD(tb[NDA_LLADDR]); | |
421 | dbase->put(dbase, &dbkey, &dbdat, 0); | |
422 | } | |
423 | } | |
424 | return 0; | |
425 | } | |
426 | ||
427 | void load_initial_table(void) | |
428 | { | |
429 | rtnl_wilddump_request(&rth, AF_INET, RTM_GETNEIGH); | |
430 | } | |
431 | ||
432 | void get_kern_msg(void) | |
433 | { | |
434 | int status; | |
435 | struct nlmsghdr *h; | |
436 | struct sockaddr_nl nladdr; | |
437 | struct iovec iov; | |
438 | char buf[8192]; | |
439 | struct msghdr msg = { | |
440 | (void*)&nladdr, sizeof(nladdr), | |
441 | &iov, 1, | |
442 | NULL, 0, | |
443 | 0 | |
444 | }; | |
445 | ||
446 | memset(&nladdr, 0, sizeof(nladdr)); | |
447 | ||
448 | iov.iov_base = buf; | |
449 | iov.iov_len = sizeof(buf); | |
450 | ||
451 | status = recvmsg(rth.fd, &msg, MSG_DONTWAIT); | |
452 | ||
453 | if (status <= 0) | |
454 | return; | |
455 | ||
456 | if (msg.msg_namelen != sizeof(nladdr)) | |
457 | return; | |
458 | ||
459 | if (nladdr.nl_pid) | |
460 | return; | |
461 | ||
462 | for (h = (struct nlmsghdr*)buf; status >= sizeof(*h); ) { | |
463 | int len = h->nlmsg_len; | |
464 | int l = len - sizeof(*h); | |
465 | ||
466 | if (l < 0 || len > status) | |
467 | return; | |
468 | ||
469 | if (do_one_request(h) < 0) | |
470 | return; | |
471 | ||
472 | status -= NLMSG_ALIGN(len); | |
473 | h = (struct nlmsghdr*)((char*)h + NLMSG_ALIGN(len)); | |
474 | } | |
475 | } | |
476 | ||
477 | /* Receive gratuitous ARP messages and store them, that's all. */ | |
478 | void get_arp_pkt(void) | |
479 | { | |
480 | unsigned char buf[1024]; | |
481 | struct sockaddr_ll sll; | |
f332d169 | 482 | socklen_t sll_len = sizeof(sll); |
aba5acdf SH |
483 | struct arphdr *a = (struct arphdr*)buf; |
484 | struct dbkey key; | |
485 | DBT dbkey, dbdat; | |
486 | int n; | |
487 | ||
f332d169 SH |
488 | n = recvfrom(pset[0].fd, buf, sizeof(buf), MSG_DONTWAIT, |
489 | (struct sockaddr*)&sll, &sll_len); | |
aba5acdf SH |
490 | if (n < 0) { |
491 | if (errno != EINTR && errno != EAGAIN) | |
492 | syslog(LOG_ERR, "recvfrom: %m"); | |
493 | return; | |
494 | } | |
495 | ||
496 | if (ifnum && !handle_if(sll.sll_ifindex)) | |
497 | return; | |
498 | ||
499 | /* Sanity checks */ | |
500 | ||
501 | if (n < sizeof(*a) || | |
502 | (a->ar_op != htons(ARPOP_REQUEST) && | |
503 | a->ar_op != htons(ARPOP_REPLY)) || | |
504 | a->ar_pln != 4 || | |
505 | a->ar_pro != htons(ETH_P_IP) || | |
506 | a->ar_hln != sll.sll_halen || | |
507 | sizeof(*a) + 2*4 + 2*a->ar_hln > n) | |
508 | return; | |
509 | ||
510 | key.iface = sll.sll_ifindex; | |
511 | memcpy(&key.addr, (char*)(a+1) + a->ar_hln, 4); | |
512 | ||
513 | /* DAD message, ignore. */ | |
514 | if (key.addr == 0) | |
515 | return; | |
516 | ||
517 | dbkey.data = &key; | |
518 | dbkey.size = sizeof(key); | |
519 | ||
520 | if (dbase->get(dbase, &dbkey, &dbdat, 0) == 0 && !IS_NEG(dbdat.data)) { | |
521 | if (memcmp(dbdat.data, a+1, dbdat.size) == 0) | |
522 | return; | |
523 | stats.arp_change++; | |
524 | } else { | |
525 | stats.arp_new++; | |
526 | } | |
527 | ||
528 | dbdat.data = a+1; | |
529 | dbdat.size = a->ar_hln; | |
530 | dbase->put(dbase, &dbkey, &dbdat, 0); | |
531 | } | |
532 | ||
533 | void catch_signal(int sig, void (*handler)(int)) | |
534 | { | |
535 | struct sigaction sa; | |
536 | ||
537 | memset(&sa, 0, sizeof(sa)); | |
538 | sa.sa_handler = handler; | |
539 | #ifdef SA_INTERRUPT | |
540 | sa.sa_flags = SA_INTERRUPT; | |
541 | #endif | |
542 | sigaction(sig, &sa, NULL); | |
543 | } | |
544 | ||
545 | #include <setjmp.h> | |
546 | sigjmp_buf env; | |
547 | volatile int in_poll; | |
548 | ||
549 | void sig_exit(int signo) | |
550 | { | |
551 | do_exit = 1; | |
552 | if (in_poll) | |
553 | siglongjmp(env, 1); | |
554 | } | |
555 | ||
556 | void sig_sync(int signo) | |
557 | { | |
558 | do_sync = 1; | |
559 | if (in_poll) | |
560 | siglongjmp(env, 1); | |
561 | } | |
562 | ||
563 | void sig_stats(int signo) | |
564 | { | |
565 | do_sync = 1; | |
566 | do_stats = 1; | |
567 | if (in_poll) | |
568 | siglongjmp(env, 1); | |
569 | } | |
570 | ||
571 | void send_stats(void) | |
572 | { | |
573 | syslog(LOG_INFO, "arp_rcv: n%lu c%lu app_rcv: tot %lu hits %lu bad %lu neg %lu sup %lu", | |
574 | stats.arp_new, stats.arp_change, | |
575 | ||
576 | stats.app_recv, stats.app_success, | |
577 | stats.app_bad, stats.app_neg, stats.app_suppressed | |
578 | ); | |
579 | syslog(LOG_INFO, "kern: n%lu c%lu neg %lu arp_send: %lu rlim %lu", | |
580 | stats.kern_new, stats.kern_change, stats.kern_neg, | |
581 | ||
582 | stats.probes_sent, stats.probes_suppressed | |
583 | ); | |
584 | do_stats = 0; | |
585 | } | |
586 | ||
587 | ||
588 | int main(int argc, char **argv) | |
589 | { | |
590 | int opt; | |
591 | int do_list = 0; | |
592 | char *do_load = NULL; | |
593 | ||
594 | while ((opt = getopt(argc, argv, "h?b:lf:a:n:kR:B:")) != EOF) { | |
595 | switch (opt) { | |
596 | case 'b': | |
597 | dbname = optarg; | |
598 | break; | |
599 | case 'f': | |
600 | if (do_load) { | |
601 | fprintf(stderr, "Duplicate option -f\n"); | |
602 | usage(); | |
603 | } | |
604 | do_load = optarg; | |
605 | break; | |
606 | case 'l': | |
607 | do_list = 1; | |
608 | break; | |
609 | case 'a': | |
610 | active_probing = atoi(optarg); | |
611 | break; | |
612 | case 'n': | |
613 | negative_timeout = atoi(optarg); | |
614 | break; | |
615 | case 'k': | |
616 | no_kernel_broadcasts = 1; | |
617 | break; | |
618 | case 'R': | |
619 | if ((broadcast_rate = atoi(optarg)) <= 0 || | |
620 | (broadcast_rate = 1000/broadcast_rate) <= 0) { | |
621 | fprintf(stderr, "Invalid ARP rate\n"); | |
622 | exit(-1); | |
623 | } | |
624 | break; | |
625 | case 'B': | |
626 | if ((broadcast_burst = atoi(optarg)) <= 0 || | |
627 | (broadcast_burst = 1000*broadcast_burst) <= 0) { | |
628 | fprintf(stderr, "Invalid ARP burst\n"); | |
629 | exit(-1); | |
630 | } | |
631 | break; | |
632 | case 'h': | |
633 | case '?': | |
634 | default: | |
635 | usage(); | |
636 | } | |
637 | } | |
638 | argc -= optind; | |
639 | argv += optind; | |
640 | ||
641 | if (argc > 0) { | |
642 | ifnum = argc; | |
643 | ifnames = argv; | |
644 | ifvec = malloc(argc*sizeof(int)); | |
645 | if (!ifvec) { | |
646 | perror("malloc"); | |
647 | exit(-1); | |
648 | } | |
649 | } | |
650 | ||
651 | if ((udp_sock = socket(AF_INET, SOCK_DGRAM, 0)) < 0) { | |
652 | perror("socket"); | |
653 | exit(-1); | |
654 | } | |
655 | ||
656 | if (ifnum) { | |
657 | int i; | |
658 | struct ifreq ifr; | |
659 | memset(&ifr, 0, sizeof(ifr)); | |
660 | for (i=0; i<ifnum; i++) { | |
661 | strncpy(ifr.ifr_name, ifnames[i], IFNAMSIZ); | |
662 | if (ioctl(udp_sock, SIOCGIFINDEX, &ifr)) { | |
663 | perror("ioctl(SIOCGIFINDEX)"); | |
664 | exit(-1);; | |
665 | } | |
666 | ifvec[i] = ifr.ifr_ifindex; | |
667 | } | |
668 | } | |
669 | ||
670 | dbase = dbopen(dbname, O_CREAT|O_RDWR, 0644, DB_HASH, NULL); | |
671 | if (dbase == NULL) { | |
672 | perror("db_open"); | |
673 | exit(-1); | |
674 | } | |
675 | ||
676 | if (do_load) { | |
677 | char buf[128]; | |
678 | FILE *fp; | |
679 | struct dbkey k; | |
680 | DBT dbkey, dbdat; | |
681 | ||
682 | dbkey.data = &k; | |
683 | dbkey.size = sizeof(k); | |
684 | ||
685 | if (strcmp(do_load, "-") == 0 || strcmp(do_load, "--") == 0) { | |
686 | fp = stdin; | |
687 | } else if ((fp = fopen(do_load, "r")) == NULL) { | |
688 | perror("fopen"); | |
689 | goto do_abort; | |
690 | } | |
691 | ||
692 | buf[sizeof(buf)-1] = 0; | |
693 | while (fgets(buf, sizeof(buf)-1, fp)) { | |
694 | __u8 b1[6]; | |
695 | char ipbuf[128]; | |
696 | char macbuf[128]; | |
697 | ||
698 | if (buf[0] == '#') | |
699 | continue; | |
700 | ||
701 | if (sscanf(buf, "%u%s%s", &k.iface, ipbuf, macbuf) != 3) { | |
702 | fprintf(stderr, "Wrong format of input file \"%s\"\n", do_load); | |
703 | goto do_abort; | |
704 | } | |
705 | if (strncmp(macbuf, "FAILED:", 7) == 0) | |
706 | continue; | |
707 | if (!inet_aton(ipbuf, (struct in_addr*)&k.addr)) { | |
708 | fprintf(stderr, "Invalid IP address: \"%s\"\n", ipbuf); | |
709 | goto do_abort; | |
710 | } | |
f332d169 | 711 | |
aba5acdf SH |
712 | dbdat.data = hexstring_a2n(macbuf, b1, 6); |
713 | if (dbdat.data == NULL) | |
714 | goto do_abort; | |
715 | dbdat.size = 6; | |
716 | ||
717 | if (dbase->put(dbase, &dbkey, &dbdat, 0)) { | |
718 | perror("hash->put"); | |
719 | goto do_abort; | |
720 | } | |
721 | } | |
722 | dbase->sync(dbase, 0); | |
723 | if (fp != stdin) | |
724 | fclose(fp); | |
725 | } | |
726 | ||
727 | if (do_list) { | |
728 | DBT dbkey, dbdat; | |
729 | printf("%-8s %-15s %s\n", "#Ifindex", "IP", "MAC"); | |
730 | while (dbase->seq(dbase, &dbkey, &dbdat, R_NEXT) == 0) { | |
731 | struct dbkey *key = dbkey.data; | |
732 | if (handle_if(key->iface)) { | |
733 | if (!IS_NEG(dbdat.data)) { | |
f332d169 | 734 | char b1[18]; |
aba5acdf SH |
735 | printf("%-8d %-15s %s\n", |
736 | key->iface, | |
737 | inet_ntoa(*(struct in_addr*)&key->addr), | |
738 | hexstring_n2a(dbdat.data, 6, b1, 18)); | |
739 | } else { | |
740 | printf("%-8d %-15s FAILED: %dsec ago\n", | |
741 | key->iface, | |
742 | inet_ntoa(*(struct in_addr*)&key->addr), | |
743 | NEG_AGE(dbdat.data)); | |
744 | } | |
745 | } | |
746 | } | |
747 | } | |
748 | ||
749 | if (do_load || do_list) | |
750 | goto out; | |
751 | ||
752 | pset[0].fd = socket(PF_PACKET, SOCK_DGRAM, 0); | |
753 | if (pset[0].fd < 0) { | |
754 | perror("socket"); | |
755 | exit(-1); | |
756 | } | |
757 | ||
758 | if (1) { | |
759 | struct sockaddr_ll sll; | |
760 | memset(&sll, 0, sizeof(sll)); | |
761 | sll.sll_family = AF_PACKET; | |
762 | sll.sll_protocol = htons(ETH_P_ARP); | |
763 | sll.sll_ifindex = (ifnum == 1 ? ifvec[0] : 0); | |
764 | if (bind(pset[0].fd, (struct sockaddr*)&sll, sizeof(sll)) < 0) { | |
765 | perror("bind"); | |
766 | goto do_abort; | |
767 | } | |
768 | } | |
769 | ||
770 | if (rtnl_open(&rth, RTMGRP_NEIGH) < 0) { | |
771 | perror("rtnl_open"); | |
772 | goto do_abort; | |
773 | } | |
774 | pset[1].fd = rth.fd; | |
775 | ||
776 | load_initial_table(); | |
777 | ||
778 | if (1) { | |
779 | int fd; | |
780 | pid_t pid = fork(); | |
781 | ||
782 | if (pid > 0) | |
783 | _exit(0); | |
784 | if (pid < 0) { | |
785 | perror("arpd: fork"); | |
786 | goto do_abort; | |
787 | } | |
788 | ||
789 | chdir("/"); | |
790 | fd = open("/dev/null", O_RDWR); | |
791 | if (fd >= 0) { | |
792 | dup2(fd, 0); | |
793 | dup2(fd, 1); | |
794 | dup2(fd, 2); | |
795 | if (fd > 2) | |
796 | close(fd); | |
797 | } | |
798 | setsid(); | |
799 | } | |
800 | ||
801 | openlog("arpd", LOG_PID | LOG_CONS, LOG_DAEMON); | |
802 | catch_signal(SIGINT, sig_exit); | |
803 | catch_signal(SIGTERM, sig_exit); | |
804 | catch_signal(SIGHUP, sig_sync); | |
805 | catch_signal(SIGUSR1, sig_stats); | |
806 | ||
807 | #define EVENTS (POLLIN|POLLPRI|POLLERR|POLLHUP) | |
808 | pset[0].events = EVENTS; | |
809 | pset[0].revents = 0; | |
810 | pset[1].events = EVENTS; | |
811 | pset[1].revents = 0; | |
812 | ||
813 | sigsetjmp(env, 1); | |
814 | ||
815 | for (;;) { | |
816 | in_poll = 1; | |
817 | ||
818 | if (do_exit) | |
819 | break; | |
820 | if (do_sync) { | |
821 | in_poll = 0; | |
822 | dbase->sync(dbase, 0); | |
823 | do_sync = 0; | |
824 | in_poll = 1; | |
825 | } | |
826 | if (do_stats) | |
827 | send_stats(); | |
828 | if (poll(pset, 2, 30000) > 0) { | |
829 | in_poll = 0; | |
830 | if (pset[0].revents&EVENTS) | |
831 | get_arp_pkt(); | |
832 | if (pset[1].revents&EVENTS) | |
833 | get_kern_msg(); | |
834 | } else { | |
835 | do_sync = 1; | |
836 | } | |
837 | } | |
838 | ||
839 | undo_sysctl_adjustments(); | |
840 | out: | |
841 | dbase->close(dbase); | |
842 | exit(0); | |
843 | ||
844 | do_abort: | |
845 | dbase->close(dbase); | |
846 | exit(-1); | |
847 | } |