blob: 1c8bb2b7309a7ad0c77a1107e54c78da5d633eaf
1 | /* vi: set sw=4 ts=4: */ |
2 | /* |
3 | * Utility routines. |
4 | * |
5 | * Connect to host at port using address resolution from getaddrinfo |
6 | * |
7 | * Licensed under GPLv2, see file LICENSE in this source tree. |
8 | */ |
9 | |
10 | #include <sys/types.h> |
11 | #include <sys/socket.h> /* netinet/in.h needs it */ |
12 | #include <netinet/in.h> |
13 | #include <net/if.h> |
14 | #include <sys/un.h> |
15 | #include "libbb.h" |
16 | |
17 | void FAST_FUNC setsockopt_reuseaddr(int fd) |
18 | { |
19 | setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &const_int_1, sizeof(const_int_1)); |
20 | } |
21 | int FAST_FUNC setsockopt_broadcast(int fd) |
22 | { |
23 | return setsockopt(fd, SOL_SOCKET, SO_BROADCAST, &const_int_1, sizeof(const_int_1)); |
24 | } |
25 | |
26 | #ifdef SO_BINDTODEVICE |
27 | int FAST_FUNC setsockopt_bindtodevice(int fd, const char *iface) |
28 | { |
29 | int r; |
30 | struct ifreq ifr; |
31 | strncpy_IFNAMSIZ(ifr.ifr_name, iface); |
32 | /* NB: passing (iface, strlen(iface) + 1) does not work! |
33 | * (maybe it works on _some_ kernels, but not on 2.6.26) |
34 | * Actually, ifr_name is at offset 0, and in practice |
35 | * just giving char[IFNAMSIZ] instead of struct ifreq works too. |
36 | * But just in case it's not true on some obscure arch... */ |
37 | r = setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE, &ifr, sizeof(ifr)); |
38 | if (r) |
39 | bb_perror_msg("can't bind to interface %s", iface); |
40 | return r; |
41 | } |
42 | #else |
43 | int FAST_FUNC setsockopt_bindtodevice(int fd UNUSED_PARAM, |
44 | const char *iface UNUSED_PARAM) |
45 | { |
46 | bb_error_msg("SO_BINDTODEVICE is not supported on this system"); |
47 | return -1; |
48 | } |
49 | #endif |
50 | |
51 | static len_and_sockaddr* get_lsa(int fd, int (*get_name)(int fd, struct sockaddr *addr, socklen_t *addrlen)) |
52 | { |
53 | len_and_sockaddr lsa; |
54 | len_and_sockaddr *lsa_ptr; |
55 | |
56 | lsa.len = LSA_SIZEOF_SA; |
57 | if (get_name(fd, &lsa.u.sa, &lsa.len) != 0) |
58 | return NULL; |
59 | |
60 | lsa_ptr = xzalloc(LSA_LEN_SIZE + lsa.len); |
61 | if (lsa.len > LSA_SIZEOF_SA) { /* rarely (if ever) happens */ |
62 | lsa_ptr->len = lsa.len; |
63 | get_name(fd, &lsa_ptr->u.sa, &lsa_ptr->len); |
64 | } else { |
65 | memcpy(lsa_ptr, &lsa, LSA_LEN_SIZE + lsa.len); |
66 | } |
67 | return lsa_ptr; |
68 | } |
69 | |
70 | len_and_sockaddr* FAST_FUNC get_sock_lsa(int fd) |
71 | { |
72 | return get_lsa(fd, getsockname); |
73 | } |
74 | |
75 | len_and_sockaddr* FAST_FUNC get_peer_lsa(int fd) |
76 | { |
77 | return get_lsa(fd, getpeername); |
78 | } |
79 | |
80 | void FAST_FUNC xconnect(int s, const struct sockaddr *s_addr, socklen_t addrlen) |
81 | { |
82 | if (connect(s, s_addr, addrlen) < 0) { |
83 | if (ENABLE_FEATURE_CLEAN_UP) |
84 | close(s); |
85 | if (s_addr->sa_family == AF_INET) |
86 | bb_perror_msg_and_die("%s (%s)", |
87 | "can't connect to remote host", |
88 | inet_ntoa(((struct sockaddr_in *)s_addr)->sin_addr)); |
89 | bb_perror_msg_and_die("can't connect to remote host"); |
90 | } |
91 | } |
92 | |
93 | /* Return port number for a service. |
94 | * If "port" is a number use it as the port. |
95 | * If "port" is a name it is looked up in /etc/services, |
96 | * if it isnt found return default_port |
97 | */ |
98 | unsigned FAST_FUNC bb_lookup_port(const char *port, const char *protocol, unsigned default_port) |
99 | { |
100 | unsigned port_nr = default_port; |
101 | if (port) { |
102 | int old_errno; |
103 | |
104 | /* Since this is a lib function, we're not allowed to reset errno to 0. |
105 | * Doing so could break an app that is deferring checking of errno. */ |
106 | old_errno = errno; |
107 | port_nr = bb_strtou(port, NULL, 10); |
108 | if (errno || port_nr > 65535) { |
109 | struct servent *tserv = getservbyname(port, protocol); |
110 | port_nr = default_port; |
111 | if (tserv) |
112 | port_nr = ntohs(tserv->s_port); |
113 | } |
114 | errno = old_errno; |
115 | } |
116 | return (uint16_t)port_nr; |
117 | } |
118 | |
119 | |
120 | /* "New" networking API */ |
121 | |
122 | |
123 | int FAST_FUNC get_nport(const struct sockaddr *sa) |
124 | { |
125 | #if ENABLE_FEATURE_IPV6 |
126 | if (sa->sa_family == AF_INET6) { |
127 | return ((struct sockaddr_in6*)sa)->sin6_port; |
128 | } |
129 | #endif |
130 | if (sa->sa_family == AF_INET) { |
131 | return ((struct sockaddr_in*)sa)->sin_port; |
132 | } |
133 | /* What? UNIX socket? IPX?? :) */ |
134 | return -1; |
135 | } |
136 | |
137 | void FAST_FUNC set_nport(struct sockaddr *sa, unsigned port) |
138 | { |
139 | #if ENABLE_FEATURE_IPV6 |
140 | if (sa->sa_family == AF_INET6) { |
141 | struct sockaddr_in6 *sin6 = (void*) sa; |
142 | sin6->sin6_port = port; |
143 | return; |
144 | } |
145 | #endif |
146 | if (sa->sa_family == AF_INET) { |
147 | struct sockaddr_in *sin = (void*) sa; |
148 | sin->sin_port = port; |
149 | return; |
150 | } |
151 | /* What? UNIX socket? IPX?? :) */ |
152 | } |
153 | |
154 | /* We hijack this constant to mean something else */ |
155 | /* It doesn't hurt because we will remove this bit anyway */ |
156 | #define DIE_ON_ERROR AI_CANONNAME |
157 | |
158 | /* host: "1.2.3.4[:port]", "www.google.com[:port]" |
159 | * port: if neither of above specifies port # */ |
160 | static len_and_sockaddr* str2sockaddr( |
161 | const char *host, int port, |
162 | IF_FEATURE_IPV6(sa_family_t af,) |
163 | int ai_flags) |
164 | { |
165 | IF_NOT_FEATURE_IPV6(sa_family_t af = AF_INET;) |
166 | int rc; |
167 | len_and_sockaddr *r; |
168 | struct addrinfo *result = NULL; |
169 | struct addrinfo *used_res; |
170 | const char *org_host = host; /* only for error msg */ |
171 | const char *cp; |
172 | struct addrinfo hint; |
173 | |
174 | if (ENABLE_FEATURE_UNIX_LOCAL && strncmp(host, "local:", 6) == 0) { |
175 | struct sockaddr_un *sun; |
176 | |
177 | r = xzalloc(LSA_LEN_SIZE + sizeof(struct sockaddr_un)); |
178 | r->len = sizeof(struct sockaddr_un); |
179 | r->u.sa.sa_family = AF_UNIX; |
180 | sun = (struct sockaddr_un *)&r->u.sa; |
181 | safe_strncpy(sun->sun_path, host + 6, sizeof(sun->sun_path)); |
182 | return r; |
183 | } |
184 | |
185 | r = NULL; |
186 | |
187 | /* Ugly parsing of host:addr */ |
188 | if (ENABLE_FEATURE_IPV6 && host[0] == '[') { |
189 | /* Even uglier parsing of [xx]:nn */ |
190 | host++; |
191 | cp = strchr(host, ']'); |
192 | if (!cp || (cp[1] != ':' && cp[1] != '\0')) { |
193 | /* Malformed: must be [xx]:nn or [xx] */ |
194 | bb_error_msg("bad address '%s'", org_host); |
195 | if (ai_flags & DIE_ON_ERROR) |
196 | xfunc_die(); |
197 | return NULL; |
198 | } |
199 | } else { |
200 | cp = strrchr(host, ':'); |
201 | if (ENABLE_FEATURE_IPV6 && cp && strchr(host, ':') != cp) { |
202 | /* There is more than one ':' (e.g. "::1") */ |
203 | cp = NULL; /* it's not a port spec */ |
204 | } |
205 | } |
206 | if (cp) { /* points to ":" or "]:" */ |
207 | int sz = cp - host + 1; |
208 | |
209 | host = safe_strncpy(alloca(sz), host, sz); |
210 | if (ENABLE_FEATURE_IPV6 && *cp != ':') { |
211 | cp++; /* skip ']' */ |
212 | if (*cp == '\0') /* [xx] without port */ |
213 | goto skip; |
214 | } |
215 | cp++; /* skip ':' */ |
216 | port = bb_strtou(cp, NULL, 10); |
217 | if (errno || (unsigned)port > 0xffff) { |
218 | bb_error_msg("bad port spec '%s'", org_host); |
219 | if (ai_flags & DIE_ON_ERROR) |
220 | xfunc_die(); |
221 | return NULL; |
222 | } |
223 | skip: ; |
224 | } |
225 | |
226 | /* Next two if blocks allow to skip getaddrinfo() |
227 | * in case host name is a numeric IP(v6) address. |
228 | * getaddrinfo() initializes DNS resolution machinery, |
229 | * scans network config and such - tens of syscalls. |
230 | */ |
231 | /* If we were not asked specifically for IPv6, |
232 | * check whether this is a numeric IPv4 */ |
233 | IF_FEATURE_IPV6(if(af != AF_INET6)) { |
234 | struct in_addr in4; |
235 | if (inet_aton(host, &in4) != 0) { |
236 | r = xzalloc(LSA_LEN_SIZE + sizeof(struct sockaddr_in)); |
237 | r->len = sizeof(struct sockaddr_in); |
238 | r->u.sa.sa_family = AF_INET; |
239 | r->u.sin.sin_addr = in4; |
240 | goto set_port; |
241 | } |
242 | } |
243 | #if ENABLE_FEATURE_IPV6 |
244 | /* If we were not asked specifically for IPv4, |
245 | * check whether this is a numeric IPv6 */ |
246 | if (af != AF_INET) { |
247 | struct in6_addr in6; |
248 | if (inet_pton(AF_INET6, host, &in6) > 0) { |
249 | r = xzalloc(LSA_LEN_SIZE + sizeof(struct sockaddr_in6)); |
250 | r->len = sizeof(struct sockaddr_in6); |
251 | r->u.sa.sa_family = AF_INET6; |
252 | r->u.sin6.sin6_addr = in6; |
253 | goto set_port; |
254 | } |
255 | } |
256 | #endif |
257 | |
258 | memset(&hint, 0 , sizeof(hint)); |
259 | hint.ai_family = af; |
260 | /* Need SOCK_STREAM, or else we get each address thrice (or more) |
261 | * for each possible socket type (tcp,udp,raw...): */ |
262 | hint.ai_socktype = SOCK_STREAM; |
263 | hint.ai_flags = ai_flags & ~DIE_ON_ERROR; |
264 | rc = getaddrinfo(host, NULL, &hint, &result); |
265 | if (rc || !result) { |
266 | bb_error_msg("bad address '%s'", org_host); |
267 | if (ai_flags & DIE_ON_ERROR) |
268 | xfunc_die(); |
269 | goto ret; |
270 | } |
271 | used_res = result; |
272 | #if ENABLE_FEATURE_PREFER_IPV4_ADDRESS |
273 | while (1) { |
274 | if (used_res->ai_family == AF_INET) |
275 | break; |
276 | used_res = used_res->ai_next; |
277 | if (!used_res) { |
278 | used_res = result; |
279 | break; |
280 | } |
281 | } |
282 | #endif |
283 | r = xmalloc(LSA_LEN_SIZE + used_res->ai_addrlen); |
284 | r->len = used_res->ai_addrlen; |
285 | memcpy(&r->u.sa, used_res->ai_addr, used_res->ai_addrlen); |
286 | |
287 | set_port: |
288 | set_nport(&r->u.sa, htons(port)); |
289 | ret: |
290 | if (result) |
291 | freeaddrinfo(result); |
292 | return r; |
293 | } |
294 | #if !ENABLE_FEATURE_IPV6 |
295 | #define str2sockaddr(host, port, af, ai_flags) str2sockaddr(host, port, ai_flags) |
296 | #endif |
297 | |
298 | #if ENABLE_FEATURE_IPV6 |
299 | len_and_sockaddr* FAST_FUNC host_and_af2sockaddr(const char *host, int port, sa_family_t af) |
300 | { |
301 | return str2sockaddr(host, port, af, 0); |
302 | } |
303 | |
304 | len_and_sockaddr* FAST_FUNC xhost_and_af2sockaddr(const char *host, int port, sa_family_t af) |
305 | { |
306 | return str2sockaddr(host, port, af, DIE_ON_ERROR); |
307 | } |
308 | #endif |
309 | |
310 | len_and_sockaddr* FAST_FUNC host2sockaddr(const char *host, int port) |
311 | { |
312 | return str2sockaddr(host, port, AF_UNSPEC, 0); |
313 | } |
314 | |
315 | len_and_sockaddr* FAST_FUNC xhost2sockaddr(const char *host, int port) |
316 | { |
317 | return str2sockaddr(host, port, AF_UNSPEC, DIE_ON_ERROR); |
318 | } |
319 | |
320 | len_and_sockaddr* FAST_FUNC xdotted2sockaddr(const char *host, int port) |
321 | { |
322 | return str2sockaddr(host, port, AF_UNSPEC, AI_NUMERICHOST | DIE_ON_ERROR); |
323 | } |
324 | |
325 | int FAST_FUNC xsocket_type(len_and_sockaddr **lsap, int family, int sock_type) |
326 | { |
327 | len_and_sockaddr *lsa; |
328 | int fd; |
329 | int len; |
330 | |
331 | if (family == AF_UNSPEC) { |
332 | #if ENABLE_FEATURE_IPV6 |
333 | fd = socket(AF_INET6, sock_type, 0); |
334 | if (fd >= 0) { |
335 | family = AF_INET6; |
336 | goto done; |
337 | } |
338 | #endif |
339 | family = AF_INET; |
340 | } |
341 | |
342 | fd = xsocket(family, sock_type, 0); |
343 | |
344 | len = sizeof(struct sockaddr_in); |
345 | if (family == AF_UNIX) |
346 | len = sizeof(struct sockaddr_un); |
347 | #if ENABLE_FEATURE_IPV6 |
348 | if (family == AF_INET6) { |
349 | done: |
350 | len = sizeof(struct sockaddr_in6); |
351 | } |
352 | #endif |
353 | lsa = xzalloc(LSA_LEN_SIZE + len); |
354 | lsa->len = len; |
355 | lsa->u.sa.sa_family = family; |
356 | *lsap = lsa; |
357 | return fd; |
358 | } |
359 | |
360 | int FAST_FUNC xsocket_stream(len_and_sockaddr **lsap) |
361 | { |
362 | return xsocket_type(lsap, AF_UNSPEC, SOCK_STREAM); |
363 | } |
364 | |
365 | static int create_and_bind_or_die(const char *bindaddr, int port, int sock_type) |
366 | { |
367 | int fd; |
368 | len_and_sockaddr *lsa; |
369 | |
370 | if (bindaddr && bindaddr[0]) { |
371 | lsa = xdotted2sockaddr(bindaddr, port); |
372 | /* user specified bind addr dictates family */ |
373 | fd = xsocket(lsa->u.sa.sa_family, sock_type, 0); |
374 | } else { |
375 | fd = xsocket_type(&lsa, AF_UNSPEC, sock_type); |
376 | set_nport(&lsa->u.sa, htons(port)); |
377 | } |
378 | setsockopt_reuseaddr(fd); |
379 | xbind(fd, &lsa->u.sa, lsa->len); |
380 | free(lsa); |
381 | return fd; |
382 | } |
383 | |
384 | int FAST_FUNC create_and_bind_stream_or_die(const char *bindaddr, int port) |
385 | { |
386 | return create_and_bind_or_die(bindaddr, port, SOCK_STREAM); |
387 | } |
388 | |
389 | int FAST_FUNC create_and_bind_dgram_or_die(const char *bindaddr, int port) |
390 | { |
391 | return create_and_bind_or_die(bindaddr, port, SOCK_DGRAM); |
392 | } |
393 | |
394 | |
395 | int FAST_FUNC create_and_connect_stream_or_die(const char *peer, int port) |
396 | { |
397 | int fd; |
398 | len_and_sockaddr *lsa; |
399 | |
400 | lsa = xhost2sockaddr(peer, port); |
401 | fd = xsocket(lsa->u.sa.sa_family, SOCK_STREAM, 0); |
402 | setsockopt_reuseaddr(fd); |
403 | xconnect(fd, &lsa->u.sa, lsa->len); |
404 | free(lsa); |
405 | return fd; |
406 | } |
407 | |
408 | int FAST_FUNC xconnect_stream(const len_and_sockaddr *lsa) |
409 | { |
410 | int fd = xsocket(lsa->u.sa.sa_family, SOCK_STREAM, 0); |
411 | xconnect(fd, &lsa->u.sa, lsa->len); |
412 | return fd; |
413 | } |
414 | |
415 | /* We hijack this constant to mean something else */ |
416 | /* It doesn't hurt because we will add this bit anyway */ |
417 | #define IGNORE_PORT NI_NUMERICSERV |
418 | static char* FAST_FUNC sockaddr2str(const struct sockaddr *sa, int flags) |
419 | { |
420 | char host[128]; |
421 | char serv[16]; |
422 | int rc; |
423 | socklen_t salen; |
424 | |
425 | if (ENABLE_FEATURE_UNIX_LOCAL && sa->sa_family == AF_UNIX) { |
426 | struct sockaddr_un *sun = (struct sockaddr_un *)sa; |
427 | return xasprintf("local:%.*s", |
428 | (int) sizeof(sun->sun_path), |
429 | sun->sun_path); |
430 | } |
431 | |
432 | salen = LSA_SIZEOF_SA; |
433 | #if ENABLE_FEATURE_IPV6 |
434 | if (sa->sa_family == AF_INET) |
435 | salen = sizeof(struct sockaddr_in); |
436 | if (sa->sa_family == AF_INET6) |
437 | salen = sizeof(struct sockaddr_in6); |
438 | #endif |
439 | rc = getnameinfo(sa, salen, |
440 | host, sizeof(host), |
441 | /* can do ((flags & IGNORE_PORT) ? NULL : serv) but why bother? */ |
442 | serv, sizeof(serv), |
443 | /* do not resolve port# into service _name_ */ |
444 | flags | NI_NUMERICSERV |
445 | ); |
446 | if (rc) |
447 | return NULL; |
448 | if (flags & IGNORE_PORT) |
449 | return xstrdup(host); |
450 | #if ENABLE_FEATURE_IPV6 |
451 | if (sa->sa_family == AF_INET6) { |
452 | if (strchr(host, ':')) /* heh, it's not a resolved hostname */ |
453 | return xasprintf("[%s]:%s", host, serv); |
454 | /*return xasprintf("%s:%s", host, serv);*/ |
455 | /* - fall through instead */ |
456 | } |
457 | #endif |
458 | /* For now we don't support anything else, so it has to be INET */ |
459 | /*if (sa->sa_family == AF_INET)*/ |
460 | return xasprintf("%s:%s", host, serv); |
461 | /*return xstrdup(host);*/ |
462 | } |
463 | |
464 | char* FAST_FUNC xmalloc_sockaddr2host(const struct sockaddr *sa) |
465 | { |
466 | return sockaddr2str(sa, 0); |
467 | } |
468 | |
469 | char* FAST_FUNC xmalloc_sockaddr2host_noport(const struct sockaddr *sa) |
470 | { |
471 | return sockaddr2str(sa, IGNORE_PORT); |
472 | } |
473 | |
474 | char* FAST_FUNC xmalloc_sockaddr2hostonly_noport(const struct sockaddr *sa) |
475 | { |
476 | return sockaddr2str(sa, NI_NAMEREQD | IGNORE_PORT); |
477 | } |
478 | char* FAST_FUNC xmalloc_sockaddr2dotted(const struct sockaddr *sa) |
479 | { |
480 | return sockaddr2str(sa, NI_NUMERICHOST); |
481 | } |
482 | |
483 | char* FAST_FUNC xmalloc_sockaddr2dotted_noport(const struct sockaddr *sa) |
484 | { |
485 | return sockaddr2str(sa, NI_NUMERICHOST | IGNORE_PORT); |
486 | } |
487 |