added --address option for virtual hosting
[rsync/rsync.git] / socket.c
CommitLineData
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1/*
2 Copyright (C) Andrew Tridgell 1998
3
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2 of the License, or
7 (at your option) any later version.
8
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
13
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software
16 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
17*/
18
19/*
20 socket functions used in rsync
21
22 */
23
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24#include "rsync.h"
25
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26
27/* establish a proxy connection on an open socket to a web roxy by using the CONNECT
28 method */
29static int establish_proxy_connection(int fd, char *host, int port)
30{
31 char buffer[1024];
32 char *cp;
33
34 slprintf(buffer, sizeof(buffer), "CONNECT %s:%d HTTP/1.0\r\n\r\n", host, port);
35 if (write(fd, buffer, strlen(buffer)) != strlen(buffer)) {
36 rprintf(FERROR, "failed to write to proxy - %s\n",
37 strerror(errno));
38 return -1;
39 }
40
41 for (cp = buffer; cp < &buffer[sizeof(buffer) - 1]; cp++) {
42 if (read(fd, cp, 1) != 1) {
43 rprintf(FERROR, "failed to read from proxy\n");
44 return -1;
45 }
46 if (*cp == '\n')
47 break;
48 }
49
50 if (*cp != '\n')
51 cp++;
52 *cp-- = '\0';
53 if (*cp == '\r')
54 *cp = '\0';
55 if (strncmp(buffer, "HTTP/", 5) != 0) {
56 rprintf(FERROR, "bad response from proxy - %s\n",
57 buffer);
58 return -1;
59 }
60 for (cp = &buffer[5]; isdigit(*cp) || (*cp == '.'); cp++)
61 ;
62 while (*cp == ' ')
63 cp++;
64 if (*cp != '2') {
65 rprintf(FERROR, "bad response from proxy - %s\n",
66 buffer);
67 return -1;
68 }
69 /* throw away the rest of the HTTP header */
70 while (1) {
71 for (cp = buffer; cp < &buffer[sizeof(buffer) - 1];
72 cp++) {
73 if (read(fd, cp, 1) != 1) {
74 rprintf(FERROR, "failed to read from proxy\n");
75 return -1;
76 }
77 if (*cp == '\n')
78 break;
79 }
80 if ((cp > buffer) && (*cp == '\n'))
81 cp--;
82 if ((cp == buffer) && ((*cp == '\n') || (*cp == '\r')))
83 break;
84 }
85 return 0;
86}
87
88
f0fca04e 89/* open a socket to a tcp remote host with the specified port
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90 based on code from Warren
91 proxy support by Stephen Rothwell */
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92int open_socket_out(char *host, int port)
93{
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94 int type = SOCK_STREAM;
95 struct sockaddr_in sock_out;
96 int res;
97 struct hostent *hp;
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98 char *h;
99 unsigned p;
100 int proxied = 0;
101 char buffer[1024];
102 char *cp;
103
104 /* if we have a RSYNC_PROXY env variable then redirect our connetcion via a web proxy
105 at the given address. The format is hostname:port */
106 h = getenv("RSYNC_PROXY");
107 proxied = (h != NULL) && (*h != '\0');
108
109 if (proxied) {
110 strlcpy(buffer, h, sizeof(buffer));
111 cp = strchr(buffer, ':');
112 if (cp == NULL) {
113 rprintf(FERROR, "invalid proxy specification\n");
114 return -1;
115 }
116 *cp++ = '\0';
117 p = atoi(cp);
118 h = buffer;
119 } else {
120 h = host;
121 p = port;
122 }
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123
124 res = socket(PF_INET, type, 0);
125 if (res == -1) {
126 return -1;
127 }
128
4c3b4b25 129 hp = gethostbyname(h);
f0fca04e 130 if (!hp) {
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131 rprintf(FERROR,"unknown host: %s\n", h);
132 close(res);
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133 return -1;
134 }
135
136 memcpy(&sock_out.sin_addr, hp->h_addr, hp->h_length);
4c3b4b25 137 sock_out.sin_port = htons(p);
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138 sock_out.sin_family = PF_INET;
139
140 if (connect(res,(struct sockaddr *)&sock_out,sizeof(sock_out))) {
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141 rprintf(FERROR,"failed to connect to %s - %s\n", h, strerror(errno));
142 close(res);
143 return -1;
144 }
145
146 if (proxied && establish_proxy_connection(res, host, port) != 0) {
f0fca04e 147 close(res);
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148 return -1;
149 }
150
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151 set_nonblocking(res);
152
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153 return res;
154}
155
156
157/****************************************************************************
158open a socket of the specified type, port and address for incoming data
159****************************************************************************/
5c9730a4 160static int open_socket_in(int type, int port, struct in_addr *address)
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161{
162 struct hostent *hp;
163 struct sockaddr_in sock;
d41c7d02 164 char host_name[MAXHOSTNAMELEN];
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165 int res;
166 int one=1;
167
168 /* get my host name */
169 if (gethostname(host_name, sizeof(host_name)) == -1) {
170 rprintf(FERROR,"gethostname failed\n");
171 return -1;
172 }
173
174 /* get host info */
175 if ((hp = gethostbyname(host_name)) == 0) {
176 rprintf(FERROR,"gethostbyname: Unknown host %s\n",host_name);
177 return -1;
178 }
179
f5780433 180 memset((char *)&sock,0,sizeof(sock));
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181 memcpy((char *)&sock.sin_addr,(char *)hp->h_addr, hp->h_length);
182 sock.sin_port = htons(port);
183 sock.sin_family = hp->h_addrtype;
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184 if (address) {
185 sock.sin_addr = *address;
186 } else {
187 sock.sin_addr.s_addr = INADDR_ANY;
188 }
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189 res = socket(hp->h_addrtype, type, 0);
190 if (res == -1) {
191 rprintf(FERROR,"socket failed\n");
192 return -1;
193 }
194
195 setsockopt(res,SOL_SOCKET,SO_REUSEADDR,(char *)&one,sizeof(one));
196
197 /* now we've got a socket - we need to bind it */
198 if (bind(res, (struct sockaddr * ) &sock,sizeof(sock)) == -1) {
199 rprintf(FERROR,"bind failed on port %d\n", port);
200 close(res);
201 return -1;
202 }
203
204 return res;
205}
206
207
208/****************************************************************************
209determine if a file descriptor is in fact a socket
210****************************************************************************/
211int is_a_socket(int fd)
212{
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213 int v,l;
214 l = sizeof(int);
215 return(getsockopt(fd, SOL_SOCKET, SO_TYPE, (char *)&v, &l) == 0);
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216}
217
218
8ef4ffd6 219void start_accept_loop(int port, int (*fn)(int ))
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220{
221 int s;
5c9730a4 222 extern struct in_addr socket_address;
f0fca04e 223
f0fca04e 224 /* open an incoming socket */
5c9730a4 225 s = open_socket_in(SOCK_STREAM, port, &socket_address);
f0fca04e 226 if (s == -1)
65417579 227 exit_cleanup(RERR_SOCKETIO);
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228
229 /* ready to listen */
230 if (listen(s, 5) == -1) {
231 close(s);
65417579 232 exit_cleanup(RERR_SOCKETIO);
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233 }
234
235
236 /* now accept incoming connections - forking a new process
237 for each incoming connection */
238 while (1) {
239 fd_set fds;
240 int fd;
241 struct sockaddr addr;
242 int in_addrlen = sizeof(addr);
243
244 FD_ZERO(&fds);
245 FD_SET(s, &fds);
246
247 if (select(s+1, &fds, NULL, NULL, NULL) != 1) {
248 continue;
249 }
250
251 if(!FD_ISSET(s, &fds)) continue;
252
253 fd = accept(s,&addr,&in_addrlen);
254
255 if (fd == -1) continue;
256
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257 signal(SIGCHLD, SIG_IGN);
258
259 /* we shouldn't have any children left hanging around
260 but I have had reports that on Digital Unix zombies
261 are produced, so this ensures that they are reaped */
262#ifdef WNOHANG
0503f060 263 while (waitpid(-1, NULL, WNOHANG) > 0);
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264#endif
265
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266 if (fork()==0) {
267 close(s);
268
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269 set_nonblocking(fd);
270
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271 _exit(fn(fd));
272 }
273
274 close(fd);
275 }
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276}
277
278
279enum SOCK_OPT_TYPES {OPT_BOOL,OPT_INT,OPT_ON};
280
281struct
282{
283 char *name;
284 int level;
285 int option;
286 int value;
287 int opttype;
288} socket_options[] = {
289 {"SO_KEEPALIVE", SOL_SOCKET, SO_KEEPALIVE, 0, OPT_BOOL},
290 {"SO_REUSEADDR", SOL_SOCKET, SO_REUSEADDR, 0, OPT_BOOL},
291 {"SO_BROADCAST", SOL_SOCKET, SO_BROADCAST, 0, OPT_BOOL},
292#ifdef TCP_NODELAY
293 {"TCP_NODELAY", IPPROTO_TCP, TCP_NODELAY, 0, OPT_BOOL},
294#endif
295#ifdef IPTOS_LOWDELAY
296 {"IPTOS_LOWDELAY", IPPROTO_IP, IP_TOS, IPTOS_LOWDELAY, OPT_ON},
297#endif
298#ifdef IPTOS_THROUGHPUT
299 {"IPTOS_THROUGHPUT", IPPROTO_IP, IP_TOS, IPTOS_THROUGHPUT, OPT_ON},
300#endif
301#ifdef SO_SNDBUF
302 {"SO_SNDBUF", SOL_SOCKET, SO_SNDBUF, 0, OPT_INT},
303#endif
304#ifdef SO_RCVBUF
305 {"SO_RCVBUF", SOL_SOCKET, SO_RCVBUF, 0, OPT_INT},
306#endif
307#ifdef SO_SNDLOWAT
308 {"SO_SNDLOWAT", SOL_SOCKET, SO_SNDLOWAT, 0, OPT_INT},
309#endif
310#ifdef SO_RCVLOWAT
311 {"SO_RCVLOWAT", SOL_SOCKET, SO_RCVLOWAT, 0, OPT_INT},
312#endif
313#ifdef SO_SNDTIMEO
314 {"SO_SNDTIMEO", SOL_SOCKET, SO_SNDTIMEO, 0, OPT_INT},
315#endif
316#ifdef SO_RCVTIMEO
317 {"SO_RCVTIMEO", SOL_SOCKET, SO_RCVTIMEO, 0, OPT_INT},
318#endif
319 {NULL,0,0,0,0}};
320
321
322
323/****************************************************************************
324set user socket options
325****************************************************************************/
326void set_socket_options(int fd, char *options)
327{
328 char *tok;
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329 if (!options || !*options) return;
330
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331 options = strdup(options);
332
333 if (!options) out_of_memory("set_socket_options");
334
335 for (tok=strtok(options, " \t,"); tok; tok=strtok(NULL," \t,")) {
336 int ret=0,i;
337 int value = 1;
338 char *p;
339 int got_value = 0;
340
341 if ((p = strchr(tok,'='))) {
342 *p = 0;
343 value = atoi(p+1);
344 got_value = 1;
345 }
346
347 for (i=0;socket_options[i].name;i++)
348 if (strcmp(socket_options[i].name,tok)==0)
349 break;
350
351 if (!socket_options[i].name) {
352 rprintf(FERROR,"Unknown socket option %s\n",tok);
353 continue;
354 }
355
356 switch (socket_options[i].opttype) {
357 case OPT_BOOL:
358 case OPT_INT:
359 ret = setsockopt(fd,socket_options[i].level,
360 socket_options[i].option,(char *)&value,sizeof(int));
361 break;
362
363 case OPT_ON:
364 if (got_value)
365 rprintf(FERROR,"syntax error - %s does not take a value\n",tok);
366
367 {
368 int on = socket_options[i].value;
369 ret = setsockopt(fd,socket_options[i].level,
370 socket_options[i].option,(char *)&on,sizeof(int));
371 }
372 break;
373 }
374
375 if (ret != 0)
376 rprintf(FERROR,"Failed to set socket option %s\n",tok);
377 }
378
379 free(options);
380}
381
382/****************************************************************************
383become a daemon, discarding the controlling terminal
384****************************************************************************/
385void become_daemon(void)
386{
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387 int i;
388
c46ded46 389 if (fork()) {
f0fca04e 390 _exit(0);
c46ded46 391 }
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392
393 /* detach from the terminal */
394#ifdef HAVE_SETSID
395 setsid();
396#else
397#ifdef TIOCNOTTY
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398 i = open("/dev/tty", O_RDWR);
399 if (i >= 0) {
400 ioctl(i, (int) TIOCNOTTY, (char *)0);
401 close(i);
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402 }
403#endif /* TIOCNOTTY */
404#endif
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405 /* make sure that stdin, stdout an stderr don't stuff things
406 up (library functions, for example) */
407 for (i=0;i<3;i++) {
408 close(i);
409 open("/dev/null", O_RDWR);
410 }
bc2e93eb 411}
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412
413/*******************************************************************
414 return the IP addr of the client as a string
415 ******************************************************************/
416char *client_addr(int fd)
417{
418 struct sockaddr sa;
419 struct sockaddr_in *sockin = (struct sockaddr_in *) (&sa);
420 int length = sizeof(sa);
421 static char addr_buf[100];
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422 static int initialised;
423
424 if (initialised) return addr_buf;
425
426 initialised = 1;
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427
428 if (getpeername(fd, &sa, &length)) {
65417579 429 exit_cleanup(RERR_SOCKETIO);
ff8b29b8 430 }
11a5a3c7 431
37f9805d 432 strlcpy(addr_buf,(char *)inet_ntoa(sockin->sin_addr), sizeof(addr_buf));
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433 return addr_buf;
434}
435
436
437/*******************************************************************
438 return the DNS name of the client
439 ******************************************************************/
440char *client_name(int fd)
441{
442 struct sockaddr sa;
443 struct sockaddr_in *sockin = (struct sockaddr_in *) (&sa);
444 int length = sizeof(sa);
445 static char name_buf[100];
446 struct hostent *hp;
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447 char **p;
448 char *def = "UNKNOWN";
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449 static int initialised;
450
451 if (initialised) return name_buf;
452
453 initialised = 1;
ff8b29b8 454
de5fb374 455 strcpy(name_buf,def);
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456
457 if (getpeername(fd, &sa, &length)) {
65417579 458 exit_cleanup(RERR_SOCKETIO);
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459 }
460
461 /* Look up the remote host name. */
462 if ((hp = gethostbyaddr((char *) &sockin->sin_addr,
463 sizeof(sockin->sin_addr),
464 AF_INET))) {
37f9805d 465 strlcpy(name_buf,(char *)hp->h_name,sizeof(name_buf));
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466 }
467
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468
469 /* do a forward lookup as well to prevent spoofing */
470 hp = gethostbyname(name_buf);
471 if (!hp) {
472 strcpy(name_buf,def);
473 rprintf(FERROR,"reverse name lookup failed\n");
474 } else {
475 for (p=hp->h_addr_list;*p;p++) {
476 if (memcmp(*p, &sockin->sin_addr, hp->h_length) == 0) {
477 break;
478 }
479 }
480 if (!*p) {
481 strcpy(name_buf,def);
482 rprintf(FERROR,"reverse name lookup mismatch - spoofed address?\n");
483 }
484 }
485
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486 return name_buf;
487}
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488
489/*******************************************************************
490convert a string to an IP address. The string can be a name or
491dotted decimal number
492 ******************************************************************/
493struct in_addr *ip_address(const char *str)
494{
495 static struct in_addr ret;
496 struct hostent *hp;
497
498 /* try as an IP address */
499 if (inet_aton(str, &ret) != 0) {
500 return &ret;
501 }
502
503 /* otherwise assume it's a network name of some sort and use
504 gethostbyname */
505 if ((hp = gethostbyname(str)) == 0) {
506 rprintf(FERROR, "gethostbyname: Unknown host. %s\n",str);
507 return NULL;
508 }
509
510 if (hp->h_addr == NULL) {
511 rprintf(FERROR, "gethostbyname: host address is invalid for host %s\n",str);
512 return NULL;
513 }
514
515 if (hp->h_length > sizeof(ret)) {
516 rprintf(FERROR, "gethostbyname: host address is too large\n");
517 return NULL;
518 }
519
520 memcpy(&ret.s_addr, hp->h_addr, hp->h_length);
521
522 return(&ret);
523}