Commit | Line | Data |
---|---|---|
0f78b815 | 1 | /* |
d5d4b282 | 2 | * Socket functions used in rsync. |
362099a5 | 3 | * |
0f78b815 WD |
4 | * Copyright (C) 1992-2001 Andrew Tridgell <tridge@samba.org> |
5 | * Copyright (C) 2001, 2002 Martin Pool <mbp@samba.org> | |
b3bf9b9d | 6 | * Copyright (C) 2003-2009 Wayne Davison |
0f78b815 WD |
7 | * |
8 | * This program is free software; you can redistribute it and/or modify | |
8e41b68e WD |
9 | * it under the terms of the GNU General Public License as published by |
10 | * the Free Software Foundation; either version 3 of the License, or | |
11 | * (at your option) any later version. | |
0f78b815 WD |
12 | * |
13 | * This program is distributed in the hope that it will be useful, | |
14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
16 | * GNU General Public License for more details. | |
17 | * | |
e7c67065 | 18 | * You should have received a copy of the GNU General Public License along |
4fd842f9 | 19 | * with this program; if not, visit the http://fsf.org website. |
0f78b815 WD |
20 | */ |
21 | ||
22 | /* This file is now converted to use the new-style getaddrinfo() | |
362099a5 MP |
23 | * interface, which supports IPv6 but is also supported on recent |
24 | * IPv4-only machines. On systems that don't have that interface, we | |
0f78b815 | 25 | * emulate it using the KAME implementation. */ |
bc2e93eb | 26 | |
f0fca04e | 27 | #include "rsync.h" |
5dd14f0c | 28 | #include "itypes.h" |
5899b8cf WD |
29 | #include <netinet/in_systm.h> |
30 | #include <netinet/ip.h> | |
0f5c1c19 | 31 | #include <netinet/tcp.h> |
f0fca04e | 32 | |
2c7d63c7 | 33 | extern char *bind_address; |
1c3e6e8b | 34 | extern char *sockopts; |
2c7d63c7 | 35 | extern int default_af_hint; |
ba22c9e2 | 36 | extern int connect_timeout; |
9a5a8673 | 37 | |
44e604f4 | 38 | #ifdef HAVE_SIGACTION |
2b28968d WD |
39 | static struct sigaction sigact; |
40 | #endif | |
41 | ||
292a5c2b WD |
42 | static int sock_exec(const char *prog); |
43 | ||
44 | /* Establish a proxy connection on an open socket to a web proxy by using the | |
45 | * CONNECT method. If proxy_user and proxy_pass are not NULL, they are used to | |
46 | * authenticate to the proxy using the "Basic" proxy-authorization protocol. */ | |
a3a84107 WD |
47 | static int establish_proxy_connection(int fd, char *host, int port, |
48 | char *proxy_user, char *proxy_pass) | |
4c3b4b25 | 49 | { |
a3a84107 WD |
50 | char *cp, buffer[1024]; |
51 | char *authhdr, authbuf[1024]; | |
52 | int len; | |
53 | ||
54 | if (proxy_user && proxy_pass) { | |
893c4cc0 WD |
55 | stringjoin(buffer, sizeof buffer, |
56 | proxy_user, ":", proxy_pass, NULL); | |
a3a84107 | 57 | len = strlen(buffer); |
4c3b4b25 | 58 | |
8030b28f | 59 | if ((len*8 + 5) / 6 >= (int)sizeof authbuf - 3) { |
a3a84107 WD |
60 | rprintf(FERROR, |
61 | "authentication information is too long\n"); | |
62 | return -1; | |
63 | } | |
64 | ||
6854bf69 | 65 | base64_encode(buffer, len, authbuf, 1); |
a3a84107 WD |
66 | authhdr = "\r\nProxy-Authorization: Basic "; |
67 | } else { | |
68 | *authbuf = '\0'; | |
69 | authhdr = ""; | |
70 | } | |
71 | ||
72 | snprintf(buffer, sizeof buffer, "CONNECT %s:%d HTTP/1.0%s%s\r\n\r\n", | |
73 | host, port, authhdr, authbuf); | |
74 | len = strlen(buffer); | |
75 | if (write(fd, buffer, len) != len) { | |
d62bcc17 | 76 | rsyserr(FERROR, errno, "failed to write to proxy"); |
4c3b4b25 AT |
77 | return -1; |
78 | } | |
79 | ||
a3a84107 | 80 | for (cp = buffer; cp < &buffer[sizeof buffer - 1]; cp++) { |
4c3b4b25 | 81 | if (read(fd, cp, 1) != 1) { |
d62bcc17 | 82 | rsyserr(FERROR, errno, "failed to read from proxy"); |
4c3b4b25 AT |
83 | return -1; |
84 | } | |
85 | if (*cp == '\n') | |
86 | break; | |
87 | } | |
88 | ||
89 | if (*cp != '\n') | |
90 | cp++; | |
91 | *cp-- = '\0'; | |
92 | if (*cp == '\r') | |
93 | *cp = '\0'; | |
94 | if (strncmp(buffer, "HTTP/", 5) != 0) { | |
4ccfd96c | 95 | rprintf(FERROR, "bad response from proxy -- %s\n", |
4c3b4b25 AT |
96 | buffer); |
97 | return -1; | |
98 | } | |
2dc7b8bd | 99 | for (cp = &buffer[5]; isDigit(cp) || *cp == '.'; cp++) {} |
4c3b4b25 AT |
100 | while (*cp == ' ') |
101 | cp++; | |
102 | if (*cp != '2') { | |
4ccfd96c | 103 | rprintf(FERROR, "bad response from proxy -- %s\n", |
4c3b4b25 AT |
104 | buffer); |
105 | return -1; | |
106 | } | |
107 | /* throw away the rest of the HTTP header */ | |
108 | while (1) { | |
a3a84107 | 109 | for (cp = buffer; cp < &buffer[sizeof buffer - 1]; cp++) { |
4c3b4b25 | 110 | if (read(fd, cp, 1) != 1) { |
d62bcc17 WD |
111 | rsyserr(FERROR, errno, |
112 | "failed to read from proxy"); | |
4c3b4b25 AT |
113 | return -1; |
114 | } | |
115 | if (*cp == '\n') | |
116 | break; | |
117 | } | |
9c07d253 | 118 | if (cp > buffer && *cp == '\n') |
4c3b4b25 | 119 | cp--; |
9c07d253 | 120 | if (cp == buffer && (*cp == '\n' || *cp == '\r')) |
4c3b4b25 AT |
121 | break; |
122 | } | |
123 | return 0; | |
124 | } | |
125 | ||
126 | ||
292a5c2b WD |
127 | /* Try to set the local address for a newly-created socket. |
128 | * Return -1 if this fails. */ | |
e028b9ff | 129 | int try_bind_local(int s, int ai_family, int ai_socktype, |
4313d6f9 | 130 | const char *bind_addr) |
f8be7d42 MP |
131 | { |
132 | int error; | |
133 | struct addrinfo bhints, *bres_all, *r; | |
134 | ||
a3a84107 | 135 | memset(&bhints, 0, sizeof bhints); |
f8be7d42 MP |
136 | bhints.ai_family = ai_family; |
137 | bhints.ai_socktype = ai_socktype; | |
138 | bhints.ai_flags = AI_PASSIVE; | |
4313d6f9 | 139 | if ((error = getaddrinfo(bind_addr, NULL, &bhints, &bres_all))) { |
f8be7d42 | 140 | rprintf(FERROR, RSYNC_NAME ": getaddrinfo %s: %s\n", |
4313d6f9 | 141 | bind_addr, gai_strerror(error)); |
f8be7d42 MP |
142 | return -1; |
143 | } | |
144 | ||
145 | for (r = bres_all; r; r = r->ai_next) { | |
9ec75284 | 146 | if (bind(s, r->ai_addr, r->ai_addrlen) == -1) |
f8be7d42 | 147 | continue; |
6b2d24de | 148 | freeaddrinfo(bres_all); |
f8be7d42 MP |
149 | return s; |
150 | } | |
151 | ||
152 | /* no error message; there might be some problem that allows | |
153 | * creation of the socket but not binding, perhaps if the | |
154 | * machine has no ipv6 address of this name. */ | |
6b2d24de | 155 | freeaddrinfo(bres_all); |
f8be7d42 MP |
156 | return -1; |
157 | } | |
158 | ||
ba22c9e2 WD |
159 | /* connect() timeout handler based on alarm() */ |
160 | static RETSIGTYPE contimeout_handler(UNUSED(int val)) | |
161 | { | |
162 | connect_timeout = -1; | |
163 | } | |
eecd22ff | 164 | |
292a5c2b | 165 | /* Open a socket to a tcp remote host with the specified port. |
06963d0f | 166 | * |
d5d4b282 MP |
167 | * Based on code from Warren. Proxy support by Stephen Rothwell. |
168 | * getaddrinfo() rewrite contributed by KAME.net. | |
06963d0f | 169 | * |
292a5c2b WD |
170 | * Now that we support IPv6 we need to look up the remote machine's address |
171 | * first, using af_hint to set a preference for the type of address. Then | |
172 | * depending on whether it has v4 or v6 addresses we try to open a connection. | |
06963d0f | 173 | * |
292a5c2b WD |
174 | * The loop allows for machines with some addresses which may not be reachable, |
175 | * perhaps because we can't e.g. route ipv6 to that network but we can get ip4 | |
176 | * packets through. | |
d5d4b282 | 177 | * |
292a5c2b | 178 | * bind_addr: local address to use. Normally NULL to bind the wildcard address. |
d5d4b282 | 179 | * |
292a5c2b | 180 | * af_hint: address family, e.g. AF_INET or AF_INET6. */ |
4313d6f9 | 181 | int open_socket_out(char *host, int port, const char *bind_addr, |
d5d4b282 | 182 | int af_hint) |
bc2e93eb | 183 | { |
f0fca04e | 184 | int type = SOCK_STREAM; |
a3a84107 | 185 | int error, s; |
06963d0f MP |
186 | struct addrinfo hints, *res0, *res; |
187 | char portbuf[10]; | |
a3a84107 | 188 | char *h, *cp; |
4c3b4b25 AT |
189 | int proxied = 0; |
190 | char buffer[1024]; | |
a3a84107 | 191 | char *proxy_user = NULL, *proxy_pass = NULL; |
4c3b4b25 | 192 | |
660c6fbd | 193 | /* if we have a RSYNC_PROXY env variable then redirect our |
a3a84107 | 194 | * connetcion via a web proxy at the given address. */ |
4c3b4b25 | 195 | h = getenv("RSYNC_PROXY"); |
9c07d253 | 196 | proxied = h != NULL && *h != '\0'; |
4c3b4b25 AT |
197 | |
198 | if (proxied) { | |
a3a84107 WD |
199 | strlcpy(buffer, h, sizeof buffer); |
200 | ||
201 | /* Is the USER:PASS@ prefix present? */ | |
b31c92ed | 202 | if ((cp = strrchr(buffer, '@')) != NULL) { |
a3a84107 WD |
203 | *cp++ = '\0'; |
204 | /* The remainder is the HOST:PORT part. */ | |
205 | h = cp; | |
206 | ||
207 | if ((cp = strchr(buffer, ':')) == NULL) { | |
208 | rprintf(FERROR, | |
209 | "invalid proxy specification: should be USER:PASS@HOST:PORT\n"); | |
210 | return -1; | |
211 | } | |
212 | *cp++ = '\0'; | |
213 | ||
214 | proxy_user = buffer; | |
215 | proxy_pass = cp; | |
216 | } else { | |
217 | /* The whole buffer is the HOST:PORT part. */ | |
218 | h = buffer; | |
219 | } | |
220 | ||
221 | if ((cp = strchr(h, ':')) == NULL) { | |
660c6fbd MP |
222 | rprintf(FERROR, |
223 | "invalid proxy specification: should be HOST:PORT\n"); | |
4c3b4b25 AT |
224 | return -1; |
225 | } | |
226 | *cp++ = '\0'; | |
a3a84107 | 227 | strlcpy(portbuf, cp, sizeof portbuf); |
951e826b | 228 | if (DEBUG_GTE(CONNECT, 1)) { |
7bea78ce MP |
229 | rprintf(FINFO, "connection via http proxy %s port %s\n", |
230 | h, portbuf); | |
231 | } | |
4c3b4b25 | 232 | } else { |
a3a84107 | 233 | snprintf(portbuf, sizeof portbuf, "%d", port); |
4c3b4b25 | 234 | h = host; |
4c3b4b25 | 235 | } |
f0fca04e | 236 | |
a3a84107 | 237 | memset(&hints, 0, sizeof hints); |
d5d4b282 | 238 | hints.ai_family = af_hint; |
06963d0f MP |
239 | hints.ai_socktype = type; |
240 | error = getaddrinfo(h, portbuf, &hints, &res0); | |
241 | if (error) { | |
d5d4b282 MP |
242 | rprintf(FERROR, RSYNC_NAME ": getaddrinfo: %s %s: %s\n", |
243 | h, portbuf, gai_strerror(error)); | |
f0fca04e AT |
244 | return -1; |
245 | } | |
246 | ||
06963d0f | 247 | s = -1; |
2d6dbe29 MP |
248 | /* Try to connect to all addresses for this machine until we get |
249 | * through. It might e.g. be multi-homed, or have both IPv4 and IPv6 | |
250 | * addresses. We need to create a socket for each record, since the | |
251 | * address record tells us what protocol to use to try to connect. */ | |
06963d0f MP |
252 | for (res = res0; res; res = res->ai_next) { |
253 | s = socket(res->ai_family, res->ai_socktype, res->ai_protocol); | |
254 | if (s < 0) | |
255 | continue; | |
f0fca04e | 256 | |
4313d6f9 | 257 | if (bind_addr |
a3a84107 | 258 | && try_bind_local(s, res->ai_family, type, |
4313d6f9 | 259 | bind_addr) == -1) { |
a3a84107 WD |
260 | close(s); |
261 | s = -1; | |
262 | continue; | |
263 | } | |
ba22c9e2 WD |
264 | if (connect_timeout > 0) { |
265 | SIGACTION(SIGALRM, contimeout_handler); | |
266 | alarm(connect_timeout); | |
267 | } | |
268 | ||
1c3e6e8b | 269 | set_socket_options(s, sockopts); |
ba22c9e2 WD |
270 | while (connect(s, res->ai_addr, res->ai_addrlen) < 0) { |
271 | if (connect_timeout < 0) | |
272 | exit_cleanup(RERR_CONTIMEOUT); | |
273 | if (errno == EINTR) | |
274 | continue; | |
06963d0f MP |
275 | close(s); |
276 | s = -1; | |
ba22c9e2 | 277 | break; |
06963d0f | 278 | } |
ba22c9e2 WD |
279 | |
280 | if (connect_timeout > 0) | |
281 | alarm(0); | |
282 | ||
283 | if (s < 0) | |
284 | continue; | |
285 | ||
a3a84107 WD |
286 | if (proxied |
287 | && establish_proxy_connection(s, host, port, | |
288 | proxy_user, proxy_pass) != 0) { | |
06963d0f MP |
289 | close(s); |
290 | s = -1; | |
291 | continue; | |
a3a84107 WD |
292 | } |
293 | break; | |
4c3b4b25 | 294 | } |
06963d0f MP |
295 | freeaddrinfo(res0); |
296 | if (s < 0) { | |
d62bcc17 | 297 | rsyserr(FERROR, errno, "failed to connect to %s", h); |
f0fca04e AT |
298 | return -1; |
299 | } | |
06963d0f | 300 | return s; |
f0fca04e AT |
301 | } |
302 | ||
303 | ||
292a5c2b | 304 | /* Open an outgoing socket, but allow for it to be intercepted by |
eecd22ff MP |
305 | * $RSYNC_CONNECT_PROG, which will execute a program across a TCP |
306 | * socketpair rather than really opening a socket. | |
307 | * | |
308 | * We use this primarily in testing to detect TCP flow bugs, but not | |
309 | * cause security problems by really opening remote connections. | |
310 | * | |
311 | * This is based on the Samba LIBSMB_PROG feature. | |
06963d0f | 312 | * |
292a5c2b | 313 | * bind_addr: local address to use. Normally NULL to get the stack default. */ |
4313d6f9 | 314 | int open_socket_out_wrapped(char *host, int port, const char *bind_addr, |
9c07d253 | 315 | int af_hint) |
eecd22ff | 316 | { |
df5cd107 | 317 | char *prog = getenv("RSYNC_CONNECT_PROG"); |
eecd22ff | 318 | |
4eff3051 | 319 | if (prog && strchr(prog, '%')) { |
e5f1a96f WD |
320 | int hlen = strlen(host); |
321 | int len = strlen(prog) + 1; | |
322 | char *f, *t; | |
323 | for (f = prog; *f; f++) { | |
324 | if (*f != '%') | |
325 | continue; | |
326 | /* Compute more than enough room. */ | |
327 | if (f[1] == '%') | |
328 | f++; | |
329 | else | |
330 | len += hlen; | |
331 | } | |
332 | f = prog; | |
333 | if (!(prog = new_array(char, len))) | |
334 | out_of_memory("open_socket_out_wrapped"); | |
335 | for (t = prog; *f; f++) { | |
336 | if (*f == '%') { | |
337 | switch (*++f) { | |
338 | case '%': | |
339 | /* Just skips the extra '%'. */ | |
340 | break; | |
341 | case 'H': | |
342 | memcpy(t, host, hlen); | |
343 | t += hlen; | |
344 | continue; | |
345 | default: | |
346 | f--; /* pass % through */ | |
347 | break; | |
348 | } | |
349 | } | |
350 | *t++ = *f; | |
351 | } | |
352 | *t = '\0'; | |
353 | } | |
354 | ||
951e826b | 355 | if (DEBUG_GTE(CONNECT, 1)) { |
df5cd107 WD |
356 | rprintf(FINFO, "%sopening tcp connection to %s port %d\n", |
357 | prog ? "Using RSYNC_CONNECT_PROG instead of " : "", | |
358 | host, port); | |
359 | } | |
360 | if (prog) | |
9c07d253 | 361 | return sock_exec(prog); |
4313d6f9 | 362 | return open_socket_out(host, port, bind_addr, af_hint); |
eecd22ff MP |
363 | } |
364 | ||
365 | ||
292a5c2b | 366 | /* Open one or more sockets for incoming data using the specified type, |
2c7d63c7 | 367 | * port, and address. |
06963d0f | 368 | * |
2c7d63c7 WD |
369 | * The getaddrinfo() call may return several address results, e.g. for |
370 | * the machine's IPv4 and IPv6 name. | |
9c07d253 | 371 | * |
2c7d63c7 WD |
372 | * We return an array of file-descriptors to the sockets, with a trailing |
373 | * -1 value to indicate the end of the list. | |
9c07d253 | 374 | * |
292a5c2b | 375 | * bind_addr: local address to bind, or NULL to allow it to default. */ |
4313d6f9 | 376 | static int *open_socket_in(int type, int port, const char *bind_addr, |
b0fd253a | 377 | int af_hint) |
f0fca04e | 378 | { |
2c7d63c7 | 379 | int one = 1; |
5c6d4632 | 380 | int s, *socks, maxs, i, ecnt; |
13e29995 | 381 | struct addrinfo hints, *all_ai, *resp; |
5c6d4632 | 382 | char portbuf[10], **errmsgs; |
06963d0f MP |
383 | int error; |
384 | ||
a3a84107 | 385 | memset(&hints, 0, sizeof hints); |
d5d4b282 | 386 | hints.ai_family = af_hint; |
06963d0f MP |
387 | hints.ai_socktype = type; |
388 | hints.ai_flags = AI_PASSIVE; | |
a3a84107 | 389 | snprintf(portbuf, sizeof portbuf, "%d", port); |
4313d6f9 | 390 | error = getaddrinfo(bind_addr, portbuf, &hints, &all_ai); |
06963d0f | 391 | if (error) { |
7ef6aa64 | 392 | rprintf(FERROR, RSYNC_NAME ": getaddrinfo: bind address %s: %s\n", |
4313d6f9 | 393 | bind_addr, gai_strerror(error)); |
b0fd253a WD |
394 | return NULL; |
395 | } | |
396 | ||
397 | /* Count max number of sockets we might open. */ | |
398 | for (maxs = 0, resp = all_ai; resp; resp = resp->ai_next, maxs++) {} | |
2c7d63c7 | 399 | |
5c6d4632 WD |
400 | socks = new_array(int, maxs + 1); |
401 | errmsgs = new_array(char *, maxs); | |
402 | if (!socks || !errmsgs) | |
2c7d63c7 | 403 | out_of_memory("open_socket_in"); |
06963d0f | 404 | |
13e29995 MP |
405 | /* We may not be able to create the socket, if for example the |
406 | * machine knows about IPv6 in the C library, but not in the | |
407 | * kernel. */ | |
5c6d4632 | 408 | for (resp = all_ai, i = ecnt = 0; resp; resp = resp->ai_next) { |
13e29995 MP |
409 | s = socket(resp->ai_family, resp->ai_socktype, |
410 | resp->ai_protocol); | |
411 | ||
b0fd253a | 412 | if (s == -1) { |
5c6d4632 WD |
413 | int r = asprintf(&errmsgs[ecnt++], |
414 | "socket(%d,%d,%d) failed: %s\n", | |
415 | (int)resp->ai_family, (int)resp->ai_socktype, | |
416 | (int)resp->ai_protocol, strerror(errno)); | |
417 | if (r < 0) | |
418 | out_of_memory("open_socket_in"); | |
13e29995 MP |
419 | /* See if there's another address that will work... */ |
420 | continue; | |
b0fd253a | 421 | } |
9c07d253 | 422 | |
13e29995 MP |
423 | setsockopt(s, SOL_SOCKET, SO_REUSEADDR, |
424 | (char *)&one, sizeof one); | |
1c3e6e8b WD |
425 | if (sockopts) |
426 | set_socket_options(s, sockopts); | |
427 | else | |
428 | set_socket_options(s, lp_socket_options()); | |
9c07d253 | 429 | |
b0fd253a WD |
430 | #ifdef IPV6_V6ONLY |
431 | if (resp->ai_family == AF_INET6) { | |
dcd08dc5 WD |
432 | if (setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY, |
433 | (char *)&one, sizeof one) < 0 | |
434 | && default_af_hint != AF_INET6) { | |
435 | close(s); | |
436 | continue; | |
437 | } | |
b0fd253a WD |
438 | } |
439 | #endif | |
440 | ||
e028b9ff WD |
441 | /* Now we've got a socket - we need to bind it. */ |
442 | if (bind(s, resp->ai_addr, resp->ai_addrlen) < 0) { | |
13e29995 | 443 | /* Nope, try another */ |
5c6d4632 | 444 | int r = asprintf(&errmsgs[ecnt++], |
e2d774cd WD |
445 | "bind() failed: %s (address-family %d)\n", |
446 | strerror(errno), (int)resp->ai_family); | |
5c6d4632 WD |
447 | if (r < 0) |
448 | out_of_memory("open_socket_in"); | |
13e29995 MP |
449 | close(s); |
450 | continue; | |
b8771f96 | 451 | } |
e23d790f | 452 | |
2c7d63c7 | 453 | socks[i++] = s; |
f0fca04e | 454 | } |
2c7d63c7 | 455 | socks[i] = -1; |
f0fca04e | 456 | |
b0fd253a WD |
457 | if (all_ai) |
458 | freeaddrinfo(all_ai); | |
b8771f96 | 459 | |
5c6d4632 WD |
460 | /* Only output the socket()/bind() messages if we were totally |
461 | * unsuccessful, or if the daemon is being run with -vv. */ | |
462 | for (s = 0; s < ecnt; s++) { | |
951e826b | 463 | if (!i || DEBUG_GTE(BIND, 1)) |
332cf6df | 464 | rwrite(FLOG, errmsgs[s], strlen(errmsgs[s]), 0); |
5c6d4632 WD |
465 | free(errmsgs[s]); |
466 | } | |
467 | free(errmsgs); | |
468 | ||
2c7d63c7 | 469 | if (!i) { |
b0fd253a | 470 | rprintf(FERROR, |
2c7d63c7 WD |
471 | "unable to bind any inbound sockets on port %d\n", |
472 | port); | |
b0fd253a WD |
473 | free(socks); |
474 | return NULL; | |
475 | } | |
476 | return socks; | |
f0fca04e AT |
477 | } |
478 | ||
479 | ||
292a5c2b | 480 | /* Determine if a file descriptor is in fact a socket. */ |
f0fca04e AT |
481 | int is_a_socket(int fd) |
482 | { | |
ac2a1a44 | 483 | int v; |
a3a84107 WD |
484 | socklen_t l = sizeof (int); |
485 | ||
486 | /* Parameters to getsockopt, setsockopt etc are very | |
487 | * unstandardized across platforms, so don't be surprised if | |
488 | * there are compiler warnings on e.g. SCO OpenSwerver or AIX. | |
489 | * It seems they all eventually get the right idea. | |
490 | * | |
491 | * Debian says: ``The fifth argument of getsockopt and | |
492 | * setsockopt is in reality an int [*] (and this is what BSD | |
493 | * 4.* and libc4 and libc5 have). Some POSIX confusion | |
494 | * resulted in the present socklen_t. The draft standard has | |
495 | * not been adopted yet, but glibc2 already follows it and | |
496 | * also has socklen_t [*]. See also accept(2).'' | |
497 | * | |
498 | * We now return to your regularly scheduled programming. */ | |
9c07d253 | 499 | return getsockopt(fd, SOL_SOCKET, SO_TYPE, (char *)&v, &l) == 0; |
f0fca04e AT |
500 | } |
501 | ||
502 | ||
067669da WD |
503 | static RETSIGTYPE sigchld_handler(UNUSED(int val)) |
504 | { | |
ca20c7fd WD |
505 | #ifdef WNOHANG |
506 | while (waitpid(-1, NULL, WNOHANG) > 0) {} | |
507 | #endif | |
44e604f4 | 508 | #ifndef HAVE_SIGACTION |
cb984e62 | 509 | signal(SIGCHLD, sigchld_handler); |
2b28968d | 510 | #endif |
ca20c7fd WD |
511 | } |
512 | ||
513 | ||
39993af5 | 514 | void start_accept_loop(int port, int (*fn)(int, int)) |
f0fca04e | 515 | { |
b0fd253a | 516 | fd_set deffds; |
d8d36af4 | 517 | int *sp, maxfd, i; |
f0fca04e | 518 | |
44e604f4 | 519 | #ifdef HAVE_SIGACTION |
2b28968d WD |
520 | sigact.sa_flags = SA_NOCLDSTOP; |
521 | #endif | |
522 | ||
f0fca04e | 523 | /* open an incoming socket */ |
b0fd253a WD |
524 | sp = open_socket_in(SOCK_STREAM, port, bind_address, default_af_hint); |
525 | if (sp == NULL) | |
65417579 | 526 | exit_cleanup(RERR_SOCKETIO); |
f0fca04e AT |
527 | |
528 | /* ready to listen */ | |
b0fd253a | 529 | FD_ZERO(&deffds); |
2c7d63c7 WD |
530 | for (i = 0, maxfd = -1; sp[i] >= 0; i++) { |
531 | if (listen(sp[i], 5) < 0) { | |
d62bcc17 | 532 | rsyserr(FERROR, errno, "listen() on socket failed"); |
4f5b0756 | 533 | #ifdef INET6 |
2c7d63c7 WD |
534 | if (errno == EADDRINUSE && i > 0) { |
535 | rprintf(FINFO, | |
880570f2 | 536 | "Try using --ipv4 or --ipv6 to avoid this listen() error.\n"); |
2c7d63c7 WD |
537 | } |
538 | #endif | |
b0fd253a WD |
539 | exit_cleanup(RERR_SOCKETIO); |
540 | } | |
541 | FD_SET(sp[i], &deffds); | |
542 | if (maxfd < sp[i]) | |
543 | maxfd = sp[i]; | |
f0fca04e AT |
544 | } |
545 | ||
f0fca04e | 546 | /* now accept incoming connections - forking a new process |
a3a84107 | 547 | * for each incoming connection */ |
f0fca04e AT |
548 | while (1) { |
549 | fd_set fds; | |
c4a5c57d | 550 | pid_t pid; |
f0fca04e | 551 | int fd; |
2d6dbe29 | 552 | struct sockaddr_storage addr; |
d54765c4 | 553 | socklen_t addrlen = sizeof addr; |
f0fca04e | 554 | |
15b84e14 | 555 | /* close log file before the potentially very long select so |
a3a84107 WD |
556 | * file can be trimmed by another process instead of growing |
557 | * forever */ | |
8ee6adef | 558 | logfile_close(); |
45a83540 | 559 | |
b0fd253a WD |
560 | #ifdef FD_COPY |
561 | FD_COPY(&deffds, &fds); | |
562 | #else | |
563 | fds = deffds; | |
564 | #endif | |
f0fca04e | 565 | |
bb499bd7 | 566 | if (select(maxfd + 1, &fds, NULL, NULL, NULL) < 1) |
9c07d253 | 567 | continue; |
f0fca04e | 568 | |
2c7d63c7 | 569 | for (i = 0, fd = -1; sp[i] >= 0; i++) { |
b0fd253a WD |
570 | if (FD_ISSET(sp[i], &fds)) { |
571 | fd = accept(sp[i], (struct sockaddr *)&addr, | |
572 | &addrlen); | |
573 | break; | |
574 | } | |
575 | } | |
f0fca04e | 576 | |
b0fd253a | 577 | if (fd < 0) |
9c07d253 | 578 | continue; |
f0fca04e | 579 | |
2b28968d | 580 | SIGACTION(SIGCHLD, sigchld_handler); |
31f440e6 | 581 | |
c4a5c57d | 582 | if ((pid = fork()) == 0) { |
9f639210 | 583 | int ret; |
2c7d63c7 WD |
584 | for (i = 0; sp[i] >= 0; i++) |
585 | close(sp[i]); | |
1da05366 | 586 | /* Re-open log file in child before possibly giving |
8ee6adef WD |
587 | * up privileges (see logfile_close() above). */ |
588 | logfile_reopen(); | |
9f639210 DD |
589 | ret = fn(fd, fd); |
590 | close_all(); | |
591 | _exit(ret); | |
c4a5c57d | 592 | } else if (pid < 0) { |
d62bcc17 WD |
593 | rsyserr(FERROR, errno, |
594 | "could not create child server process"); | |
c4a5c57d MP |
595 | close(fd); |
596 | /* This might have happened because we're | |
597 | * overloaded. Sleep briefly before trying to | |
598 | * accept again. */ | |
599 | sleep(2); | |
bd37c666 | 600 | } else { |
79845f28 | 601 | /* Parent doesn't need this fd anymore. */ |
bd37c666 | 602 | close(fd); |
f0fca04e | 603 | } |
f0fca04e | 604 | } |
f0fca04e AT |
605 | } |
606 | ||
607 | ||
608 | enum SOCK_OPT_TYPES {OPT_BOOL,OPT_INT,OPT_ON}; | |
609 | ||
610 | struct | |
611 | { | |
612 | char *name; | |
613 | int level; | |
614 | int option; | |
615 | int value; | |
616 | int opttype; | |
617 | } socket_options[] = { | |
618 | {"SO_KEEPALIVE", SOL_SOCKET, SO_KEEPALIVE, 0, OPT_BOOL}, | |
619 | {"SO_REUSEADDR", SOL_SOCKET, SO_REUSEADDR, 0, OPT_BOOL}, | |
620 | {"SO_BROADCAST", SOL_SOCKET, SO_BROADCAST, 0, OPT_BOOL}, | |
621 | #ifdef TCP_NODELAY | |
622 | {"TCP_NODELAY", IPPROTO_TCP, TCP_NODELAY, 0, OPT_BOOL}, | |
623 | #endif | |
624 | #ifdef IPTOS_LOWDELAY | |
625 | {"IPTOS_LOWDELAY", IPPROTO_IP, IP_TOS, IPTOS_LOWDELAY, OPT_ON}, | |
626 | #endif | |
627 | #ifdef IPTOS_THROUGHPUT | |
628 | {"IPTOS_THROUGHPUT", IPPROTO_IP, IP_TOS, IPTOS_THROUGHPUT, OPT_ON}, | |
629 | #endif | |
630 | #ifdef SO_SNDBUF | |
631 | {"SO_SNDBUF", SOL_SOCKET, SO_SNDBUF, 0, OPT_INT}, | |
632 | #endif | |
633 | #ifdef SO_RCVBUF | |
634 | {"SO_RCVBUF", SOL_SOCKET, SO_RCVBUF, 0, OPT_INT}, | |
635 | #endif | |
636 | #ifdef SO_SNDLOWAT | |
637 | {"SO_SNDLOWAT", SOL_SOCKET, SO_SNDLOWAT, 0, OPT_INT}, | |
638 | #endif | |
639 | #ifdef SO_RCVLOWAT | |
640 | {"SO_RCVLOWAT", SOL_SOCKET, SO_RCVLOWAT, 0, OPT_INT}, | |
641 | #endif | |
642 | #ifdef SO_SNDTIMEO | |
643 | {"SO_SNDTIMEO", SOL_SOCKET, SO_SNDTIMEO, 0, OPT_INT}, | |
644 | #endif | |
645 | #ifdef SO_RCVTIMEO | |
646 | {"SO_RCVTIMEO", SOL_SOCKET, SO_RCVTIMEO, 0, OPT_INT}, | |
647 | #endif | |
292a5c2b WD |
648 | {NULL,0,0,0,0} |
649 | }; | |
9c07d253 | 650 | |
f0fca04e | 651 | |
292a5c2b | 652 | /* Set user socket options. */ |
f0fca04e AT |
653 | void set_socket_options(int fd, char *options) |
654 | { | |
655 | char *tok; | |
9c07d253 WD |
656 | |
657 | if (!options || !*options) | |
658 | return; | |
a6801c39 | 659 | |
f0fca04e | 660 | options = strdup(options); |
f0fca04e | 661 | |
9c07d253 WD |
662 | if (!options) |
663 | out_of_memory("set_socket_options"); | |
664 | ||
665 | for (tok = strtok(options, " \t,"); tok; tok = strtok(NULL," \t,")) { | |
f0fca04e AT |
666 | int ret=0,i; |
667 | int value = 1; | |
668 | char *p; | |
669 | int got_value = 0; | |
670 | ||
671 | if ((p = strchr(tok,'='))) { | |
672 | *p = 0; | |
673 | value = atoi(p+1); | |
674 | got_value = 1; | |
675 | } | |
676 | ||
9c07d253 | 677 | for (i = 0; socket_options[i].name; i++) { |
f0fca04e AT |
678 | if (strcmp(socket_options[i].name,tok)==0) |
679 | break; | |
9c07d253 | 680 | } |
f0fca04e AT |
681 | |
682 | if (!socket_options[i].name) { | |
683 | rprintf(FERROR,"Unknown socket option %s\n",tok); | |
684 | continue; | |
685 | } | |
686 | ||
687 | switch (socket_options[i].opttype) { | |
688 | case OPT_BOOL: | |
689 | case OPT_INT: | |
690 | ret = setsockopt(fd,socket_options[i].level, | |
a3a84107 WD |
691 | socket_options[i].option, |
692 | (char *)&value, sizeof (int)); | |
f0fca04e | 693 | break; |
9c07d253 | 694 | |
f0fca04e AT |
695 | case OPT_ON: |
696 | if (got_value) | |
4ccfd96c | 697 | rprintf(FERROR,"syntax error -- %s does not take a value\n",tok); |
f0fca04e AT |
698 | |
699 | { | |
700 | int on = socket_options[i].value; | |
701 | ret = setsockopt(fd,socket_options[i].level, | |
a3a84107 WD |
702 | socket_options[i].option, |
703 | (char *)&on, sizeof (int)); | |
f0fca04e | 704 | } |
9c07d253 | 705 | break; |
f0fca04e | 706 | } |
9c07d253 | 707 | |
d62bcc17 WD |
708 | if (ret != 0) { |
709 | rsyserr(FERROR, errno, | |
710 | "failed to set socket option %s", tok); | |
711 | } | |
f0fca04e AT |
712 | } |
713 | ||
714 | free(options); | |
715 | } | |
716 | ||
eecd22ff | 717 | |
292a5c2b WD |
718 | /* This is like socketpair but uses tcp. The function guarantees that nobody |
719 | * else can attach to the socket, or if they do that this function fails and | |
720 | * the socket gets closed. Returns 0 on success, -1 on failure. The resulting | |
721 | * file descriptors are symmetrical. Currently only for RSYNC_CONNECT_PROG. */ | |
eecd22ff MP |
722 | static int socketpair_tcp(int fd[2]) |
723 | { | |
724 | int listener; | |
725 | struct sockaddr_in sock; | |
726 | struct sockaddr_in sock2; | |
a3a84107 | 727 | socklen_t socklen = sizeof sock; |
eb8ffa90 | 728 | int connect_done = 0; |
9c07d253 | 729 | |
eecd22ff MP |
730 | fd[0] = fd[1] = listener = -1; |
731 | ||
a3a84107 | 732 | memset(&sock, 0, sizeof sock); |
9c07d253 WD |
733 | |
734 | if ((listener = socket(PF_INET, SOCK_STREAM, 0)) == -1) | |
735 | goto failed; | |
eecd22ff | 736 | |
a3a84107 | 737 | memset(&sock2, 0, sizeof sock2); |
4f5b0756 | 738 | #ifdef HAVE_SOCKADDR_IN_LEN |
a3a84107 | 739 | sock2.sin_len = sizeof sock2; |
eecd22ff | 740 | #endif |
a3a84107 | 741 | sock2.sin_family = PF_INET; |
292a5c2b | 742 | sock2.sin_addr.s_addr = htonl(INADDR_LOOPBACK); |
eecd22ff | 743 | |
292a5c2b WD |
744 | if (bind(listener, (struct sockaddr *)&sock2, sizeof sock2) != 0 |
745 | || listen(listener, 1) != 0 | |
746 | || getsockname(listener, (struct sockaddr *)&sock, &socklen) != 0 | |
747 | || (fd[1] = socket(PF_INET, SOCK_STREAM, 0)) == -1) | |
9c07d253 | 748 | goto failed; |
eecd22ff MP |
749 | |
750 | set_nonblocking(fd[1]); | |
751 | ||
752 | sock.sin_addr.s_addr = htonl(INADDR_LOOPBACK); | |
753 | ||
a3a84107 | 754 | if (connect(fd[1], (struct sockaddr *)&sock, sizeof sock) == -1) { |
9c07d253 WD |
755 | if (errno != EINPROGRESS) |
756 | goto failed; | |
757 | } else | |
eecd22ff | 758 | connect_done = 1; |
eecd22ff | 759 | |
292a5c2b | 760 | if ((fd[0] = accept(listener, (struct sockaddr *)&sock2, &socklen)) == -1) |
9c07d253 | 761 | goto failed; |
eecd22ff MP |
762 | |
763 | close(listener); | |
ab217f7f WD |
764 | listener = -1; |
765 | ||
766 | set_blocking(fd[1]); | |
767 | ||
eecd22ff | 768 | if (connect_done == 0) { |
a3a84107 | 769 | if (connect(fd[1], (struct sockaddr *)&sock, sizeof sock) != 0 |
9c07d253 WD |
770 | && errno != EISCONN) |
771 | goto failed; | |
eecd22ff MP |
772 | } |
773 | ||
eecd22ff MP |
774 | /* all OK! */ |
775 | return 0; | |
776 | ||
777 | failed: | |
9c07d253 WD |
778 | if (fd[0] != -1) |
779 | close(fd[0]); | |
780 | if (fd[1] != -1) | |
781 | close(fd[1]); | |
782 | if (listener != -1) | |
783 | close(listener); | |
eecd22ff MP |
784 | return -1; |
785 | } | |
786 | ||
787 | ||
292a5c2b WD |
788 | /* Run a program on a local tcp socket, so that we can talk to it's stdin and |
789 | * stdout. This is used to fake a connection to a daemon for testing -- not | |
790 | * for the normal case of running SSH. | |
d02984bb | 791 | * |
292a5c2b WD |
792 | * Retruns a socket which is attached to a subprocess running "prog". stdin and |
793 | * stdout are attached. stderr is left attached to the original stderr. */ | |
794 | static int sock_exec(const char *prog) | |
eecd22ff | 795 | { |
94112924 | 796 | pid_t pid; |
eecd22ff | 797 | int fd[2]; |
9c07d253 | 798 | |
eecd22ff | 799 | if (socketpair_tcp(fd) != 0) { |
d62bcc17 | 800 | rsyserr(FERROR, errno, "socketpair_tcp failed"); |
eecd22ff MP |
801 | return -1; |
802 | } | |
951e826b | 803 | if (DEBUG_GTE(CMD, 1)) |
df5cd107 | 804 | rprintf(FINFO, "Running socket program: \"%s\"\n", prog); |
94112924 WD |
805 | |
806 | pid = fork(); | |
807 | if (pid < 0) { | |
808 | rsyserr(FERROR, errno, "fork"); | |
809 | exit_cleanup(RERR_IPC); | |
810 | } | |
811 | ||
812 | if (pid == 0) { | |
eecd22ff | 813 | close(fd[0]); |
94112924 WD |
814 | if (dup2(fd[1], STDIN_FILENO) < 0 |
815 | || dup2(fd[1], STDOUT_FILENO) < 0) { | |
816 | fprintf(stderr, "Failed to run \"%s\"\n", prog); | |
817 | exit(1); | |
818 | } | |
9c07d253 | 819 | exit(system(prog)); |
eecd22ff | 820 | } |
94112924 | 821 | |
9c07d253 | 822 | close(fd[1]); |
eecd22ff MP |
823 | return fd[0]; |
824 | } |