Contents of /trunk/mkinitrd-magellan/busybox/networking/arping.c
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Sat Sep 1 22:45:15 2007 UTC (17 years ago) by niro
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File size: 10025 byte(s)
Sat Sep 1 22:45:15 2007 UTC (17 years ago) by niro
File MIME type: text/plain
File size: 10025 byte(s)
-import if magellan mkinitrd; it is a fork of redhats mkinitrd-5.0.8 with all magellan patches and features; deprecates magellan-src/mkinitrd
1 | /* vi: set sw=4 ts=4: */ |
2 | /* |
3 | * arping.c - Ping hosts by ARP requests/replies |
4 | * |
5 | * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. |
6 | * |
7 | * Author: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> |
8 | * Busybox port: Nick Fedchik <nick@fedchik.org.ua> |
9 | */ |
10 | |
11 | #include <sys/ioctl.h> |
12 | #include <signal.h> |
13 | |
14 | #include <arpa/inet.h> |
15 | #include <net/if.h> |
16 | #include <netinet/ether.h> |
17 | #include <netpacket/packet.h> |
18 | |
19 | #include "busybox.h" |
20 | |
21 | static struct in_addr src; |
22 | static struct in_addr dst; |
23 | static struct sockaddr_ll me; |
24 | static struct sockaddr_ll he; |
25 | static struct timeval last; |
26 | |
27 | enum cfg_e { |
28 | dad = 1, |
29 | unsolicited = 2, |
30 | advert = 4, |
31 | quiet = 8, |
32 | quit_on_reply = 16, |
33 | broadcast_only = 32, |
34 | unicasting = 64 |
35 | }; |
36 | static int cfg; |
37 | |
38 | static int s; |
39 | static unsigned count = UINT_MAX; |
40 | static unsigned timeout; |
41 | static int sent; |
42 | static int brd_sent; |
43 | static int received; |
44 | static int brd_recv; |
45 | static int req_recv; |
46 | |
47 | #define MS_TDIFF(tv1,tv2) ( ((tv1).tv_sec-(tv2).tv_sec)*1000 + \ |
48 | ((tv1).tv_usec-(tv2).tv_usec)/1000 ) |
49 | |
50 | static int send_pack(int sock, struct in_addr *src_addr, |
51 | struct in_addr *dst_addr, struct sockaddr_ll *ME, |
52 | struct sockaddr_ll *HE) |
53 | { |
54 | int err; |
55 | struct timeval now; |
56 | RESERVE_CONFIG_UBUFFER(buf, 256); |
57 | struct arphdr *ah = (struct arphdr *) buf; |
58 | unsigned char *p = (unsigned char *) (ah + 1); |
59 | |
60 | ah->ar_hrd = htons(ME->sll_hatype); |
61 | ah->ar_hrd = htons(ARPHRD_ETHER); |
62 | ah->ar_pro = htons(ETH_P_IP); |
63 | ah->ar_hln = ME->sll_halen; |
64 | ah->ar_pln = 4; |
65 | ah->ar_op = cfg & advert ? htons(ARPOP_REPLY) : htons(ARPOP_REQUEST); |
66 | |
67 | memcpy(p, &ME->sll_addr, ah->ar_hln); |
68 | p += ME->sll_halen; |
69 | |
70 | memcpy(p, src_addr, 4); |
71 | p += 4; |
72 | |
73 | if (cfg & advert) |
74 | memcpy(p, &ME->sll_addr, ah->ar_hln); |
75 | else |
76 | memcpy(p, &HE->sll_addr, ah->ar_hln); |
77 | p += ah->ar_hln; |
78 | |
79 | memcpy(p, dst_addr, 4); |
80 | p += 4; |
81 | |
82 | gettimeofday(&now, NULL); |
83 | err = sendto(sock, buf, p - buf, 0, (struct sockaddr *) HE, sizeof(*HE)); |
84 | if (err == p - buf) { |
85 | last = now; |
86 | sent++; |
87 | if (!(cfg & unicasting)) |
88 | brd_sent++; |
89 | } |
90 | RELEASE_CONFIG_BUFFER(buf); |
91 | return err; |
92 | } |
93 | |
94 | static void finish(void) |
95 | { |
96 | if (!(cfg & quiet)) { |
97 | printf("Sent %d probe(s) (%d broadcast(s))\n" |
98 | "Received %d repl%s" |
99 | " (%d request(s), %d broadcast(s))\n", |
100 | sent, brd_sent, |
101 | received, (received == 1) ? "ies" : "y", |
102 | req_recv, brd_recv); |
103 | } |
104 | if (cfg & dad) |
105 | exit(!!received); |
106 | if (cfg & unsolicited) |
107 | exit(0); |
108 | exit(!received); |
109 | } |
110 | |
111 | static void catcher(void) |
112 | { |
113 | struct timeval tv; |
114 | static struct timeval start; |
115 | |
116 | gettimeofday(&tv, NULL); |
117 | |
118 | if (start.tv_sec == 0) |
119 | start = tv; |
120 | |
121 | if (count-- == 0 |
122 | || (timeout && MS_TDIFF(tv, start) > timeout * 1000 + 500)) |
123 | finish(); |
124 | |
125 | if (last.tv_sec == 0 || MS_TDIFF(tv, last) > 500) { |
126 | send_pack(s, &src, &dst, &me, &he); |
127 | if (count == 0 && (cfg & unsolicited)) |
128 | finish(); |
129 | } |
130 | alarm(1); |
131 | } |
132 | |
133 | static int recv_pack(unsigned char *buf, int len, struct sockaddr_ll *FROM) |
134 | { |
135 | struct arphdr *ah = (struct arphdr *) buf; |
136 | unsigned char *p = (unsigned char *) (ah + 1); |
137 | struct in_addr src_ip, dst_ip; |
138 | |
139 | /* Filter out wild packets */ |
140 | if (FROM->sll_pkttype != PACKET_HOST |
141 | && FROM->sll_pkttype != PACKET_BROADCAST |
142 | && FROM->sll_pkttype != PACKET_MULTICAST) |
143 | return 0; |
144 | |
145 | /* Only these types are recognised */ |
146 | if (ah->ar_op != htons(ARPOP_REQUEST) && ah->ar_op != htons(ARPOP_REPLY)) |
147 | return 0; |
148 | |
149 | /* ARPHRD check and this darned FDDI hack here :-( */ |
150 | if (ah->ar_hrd != htons(FROM->sll_hatype) |
151 | && (FROM->sll_hatype != ARPHRD_FDDI || ah->ar_hrd != htons(ARPHRD_ETHER))) |
152 | return 0; |
153 | |
154 | /* Protocol must be IP. */ |
155 | if (ah->ar_pro != htons(ETH_P_IP)) |
156 | return 0; |
157 | if (ah->ar_pln != 4) |
158 | return 0; |
159 | if (ah->ar_hln != me.sll_halen) |
160 | return 0; |
161 | if (len < sizeof(*ah) + 2 * (4 + ah->ar_hln)) |
162 | return 0; |
163 | memcpy(&src_ip, p + ah->ar_hln, 4); |
164 | memcpy(&dst_ip, p + ah->ar_hln + 4 + ah->ar_hln, 4); |
165 | if (!(cfg & dad)) { |
166 | if (src_ip.s_addr != dst.s_addr) |
167 | return 0; |
168 | if (src.s_addr != dst_ip.s_addr) |
169 | return 0; |
170 | if (memcmp(p + ah->ar_hln + 4, &me.sll_addr, ah->ar_hln)) |
171 | return 0; |
172 | } else { |
173 | /* DAD packet was: |
174 | src_ip = 0 (or some src) |
175 | src_hw = ME |
176 | dst_ip = tested address |
177 | dst_hw = <unspec> |
178 | |
179 | We fail, if receive request/reply with: |
180 | src_ip = tested_address |
181 | src_hw != ME |
182 | if src_ip in request was not zero, check |
183 | also that it matches to dst_ip, otherwise |
184 | dst_ip/dst_hw do not matter. |
185 | */ |
186 | if (src_ip.s_addr != dst.s_addr) |
187 | return 0; |
188 | if (memcmp(p, &me.sll_addr, me.sll_halen) == 0) |
189 | return 0; |
190 | if (src.s_addr && src.s_addr != dst_ip.s_addr) |
191 | return 0; |
192 | } |
193 | if (!(cfg & quiet)) { |
194 | int s_printed = 0; |
195 | struct timeval tv; |
196 | |
197 | gettimeofday(&tv, NULL); |
198 | |
199 | printf("%scast re%s from %s [%s]", |
200 | FROM->sll_pkttype == PACKET_HOST ? "Uni" : "Broad", |
201 | ah->ar_op == htons(ARPOP_REPLY) ? "ply" : "quest", |
202 | inet_ntoa(src_ip), |
203 | ether_ntoa((struct ether_addr *) p)); |
204 | if (dst_ip.s_addr != src.s_addr) { |
205 | printf("for %s ", inet_ntoa(dst_ip)); |
206 | s_printed = 1; |
207 | } |
208 | if (memcmp(p + ah->ar_hln + 4, me.sll_addr, ah->ar_hln)) { |
209 | if (!s_printed) |
210 | printf("for "); |
211 | printf("[%s]", |
212 | ether_ntoa((struct ether_addr *) p + ah->ar_hln + 4)); |
213 | } |
214 | |
215 | if (last.tv_sec) { |
216 | long usecs = (tv.tv_sec - last.tv_sec) * 1000000 + |
217 | tv.tv_usec - last.tv_usec; |
218 | long msecs = (usecs + 500) / 1000; |
219 | |
220 | usecs -= msecs * 1000 - 500; |
221 | printf(" %ld.%03ldms\n", msecs, usecs); |
222 | } else { |
223 | printf(" UNSOLICITED?\n"); |
224 | } |
225 | fflush(stdout); |
226 | } |
227 | received++; |
228 | if (FROM->sll_pkttype != PACKET_HOST) |
229 | brd_recv++; |
230 | if (ah->ar_op == htons(ARPOP_REQUEST)) |
231 | req_recv++; |
232 | if (cfg & quit_on_reply) |
233 | finish(); |
234 | if (!(cfg & broadcast_only)) { |
235 | memcpy(he.sll_addr, p, me.sll_halen); |
236 | cfg |= unicasting; |
237 | } |
238 | return 1; |
239 | } |
240 | |
241 | int arping_main(int argc, char **argv) |
242 | { |
243 | char *device = "eth0"; |
244 | int ifindex; |
245 | char *source = NULL; |
246 | char *target; |
247 | |
248 | s = xsocket(PF_PACKET, SOCK_DGRAM, 0); |
249 | |
250 | // Drop suid root privileges |
251 | xsetuid(getuid()); |
252 | |
253 | { |
254 | unsigned opt; |
255 | char *_count, *_timeout; |
256 | |
257 | /* Dad also sets quit_on_reply. |
258 | * Advert also sets unsolicited. |
259 | */ |
260 | opt_complementary = "Df:AU"; |
261 | opt = getopt32(argc, argv, "DUAqfbc:w:i:s:", |
262 | &_count, &_timeout, &device, &source); |
263 | cfg |= opt & 0x3f; /* set respective flags */ |
264 | if (opt & 0x40) /* -c: count */ |
265 | count = xatou(_count); |
266 | if (opt & 0x80) /* -w: timeout */ |
267 | timeout = xatoul_range(_timeout, 0, INT_MAX/2000); |
268 | //if (opt & 0x100) /* -i: interface */ |
269 | if (strlen(device) > IF_NAMESIZE) { |
270 | bb_error_msg_and_die("interface name '%s' is too long", |
271 | device); |
272 | } |
273 | //if (opt & 0x200) /* -s: source */ |
274 | } |
275 | argc -= optind; |
276 | argv += optind; |
277 | |
278 | if (argc != 1) |
279 | bb_show_usage(); |
280 | |
281 | target = *argv; |
282 | |
283 | xfunc_error_retval = 2; |
284 | |
285 | { |
286 | struct ifreq ifr; |
287 | |
288 | memset(&ifr, 0, sizeof(ifr)); |
289 | strncpy(ifr.ifr_name, device, IFNAMSIZ - 1); |
290 | if (ioctl(s, SIOCGIFINDEX, &ifr) < 0) { |
291 | bb_error_msg_and_die("interface %s not found", device); |
292 | } |
293 | ifindex = ifr.ifr_ifindex; |
294 | |
295 | if (ioctl(s, SIOCGIFFLAGS, (char *) &ifr)) { |
296 | bb_error_msg_and_die("SIOCGIFFLAGS"); |
297 | } |
298 | if (!(ifr.ifr_flags & IFF_UP)) { |
299 | bb_error_msg_and_die("interface %s is down", device); |
300 | } |
301 | if (ifr.ifr_flags & (IFF_NOARP | IFF_LOOPBACK)) { |
302 | bb_error_msg("interface %s is not ARPable", device); |
303 | return (cfg & dad ? 0 : 2); |
304 | } |
305 | } |
306 | |
307 | if (!inet_aton(target, &dst)) { |
308 | struct hostent *hp; |
309 | |
310 | hp = gethostbyname2(target, AF_INET); |
311 | if (!hp) { |
312 | bb_error_msg_and_die("invalid or unknown target %s", target); |
313 | } |
314 | memcpy(&dst, hp->h_addr, 4); |
315 | } |
316 | |
317 | if (source && !inet_aton(source, &src)) { |
318 | bb_error_msg_and_die("invalid source address %s", source); |
319 | } |
320 | |
321 | if (!(cfg & dad) && (cfg & unsolicited) && src.s_addr == 0) |
322 | src = dst; |
323 | |
324 | if (!(cfg & dad) || src.s_addr) { |
325 | struct sockaddr_in saddr; |
326 | int probe_fd = xsocket(AF_INET, SOCK_DGRAM, 0); |
327 | |
328 | if (device) { |
329 | if (setsockopt(probe_fd, SOL_SOCKET, SO_BINDTODEVICE, device, strlen(device) + 1) == -1) |
330 | bb_error_msg("warning: interface %s is ignored", device); |
331 | } |
332 | memset(&saddr, 0, sizeof(saddr)); |
333 | saddr.sin_family = AF_INET; |
334 | if (src.s_addr) { |
335 | saddr.sin_addr = src; |
336 | xbind(probe_fd, (struct sockaddr *) &saddr, sizeof(saddr)); |
337 | } else if (!(cfg & dad)) { |
338 | static const int on = 1; |
339 | socklen_t alen = sizeof(saddr); |
340 | |
341 | saddr.sin_port = htons(1025); |
342 | saddr.sin_addr = dst; |
343 | |
344 | if (setsockopt(probe_fd, SOL_SOCKET, SO_DONTROUTE, (char *) &on, sizeof(on)) == -1) |
345 | bb_perror_msg("warning: setsockopt(SO_DONTROUTE)"); |
346 | xconnect(probe_fd, (struct sockaddr *) &saddr, sizeof(saddr)); |
347 | if (getsockname(probe_fd, (struct sockaddr *) &saddr, &alen) == -1) { |
348 | bb_error_msg_and_die("getsockname"); |
349 | } |
350 | src = saddr.sin_addr; |
351 | } |
352 | close(probe_fd); |
353 | } |
354 | |
355 | me.sll_family = AF_PACKET; |
356 | me.sll_ifindex = ifindex; |
357 | me.sll_protocol = htons(ETH_P_ARP); |
358 | xbind(s, (struct sockaddr *) &me, sizeof(me)); |
359 | |
360 | { |
361 | socklen_t alen = sizeof(me); |
362 | |
363 | if (getsockname(s, (struct sockaddr *) &me, &alen) == -1) { |
364 | bb_error_msg_and_die("getsockname"); |
365 | } |
366 | } |
367 | if (me.sll_halen == 0) { |
368 | bb_error_msg("interface \"%s\" is not ARPable (no ll address)", device); |
369 | return (cfg & dad ? 0 : 2); |
370 | } |
371 | he = me; |
372 | memset(he.sll_addr, -1, he.sll_halen); |
373 | |
374 | if (!(cfg & quiet)) { |
375 | printf("ARPING to %s from %s via %s\n", |
376 | inet_ntoa(dst), inet_ntoa(src), |
377 | device ? device : "unknown"); |
378 | } |
379 | |
380 | if (!src.s_addr && !(cfg & dad)) { |
381 | bb_error_msg_and_die("no src address in the non-DAD mode"); |
382 | } |
383 | |
384 | { |
385 | struct sigaction sa; |
386 | |
387 | memset(&sa, 0, sizeof(sa)); |
388 | sa.sa_flags = SA_RESTART; |
389 | |
390 | sa.sa_handler = (void (*)(int)) finish; |
391 | sigaction(SIGINT, &sa, NULL); |
392 | |
393 | sa.sa_handler = (void (*)(int)) catcher; |
394 | sigaction(SIGALRM, &sa, NULL); |
395 | } |
396 | |
397 | catcher(); |
398 | |
399 | while (1) { |
400 | sigset_t sset, osset; |
401 | RESERVE_CONFIG_UBUFFER(packet, 4096); |
402 | struct sockaddr_ll from; |
403 | socklen_t alen = sizeof(from); |
404 | int cc; |
405 | |
406 | cc = recvfrom(s, packet, 4096, 0, (struct sockaddr *) &from, &alen); |
407 | if (cc < 0) { |
408 | bb_perror_msg("recvfrom"); |
409 | continue; |
410 | } |
411 | sigemptyset(&sset); |
412 | sigaddset(&sset, SIGALRM); |
413 | sigaddset(&sset, SIGINT); |
414 | sigprocmask(SIG_BLOCK, &sset, &osset); |
415 | recv_pack(packet, cc, &from); |
416 | sigprocmask(SIG_SETMASK, &osset, NULL); |
417 | RELEASE_CONFIG_BUFFER(packet); |
418 | } |
419 | } |