1 /* -*- c-file-style: "linux" -*-
3 Copyright (C) 1998-2001 by Andrew Tridgell
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software
17 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21 socket functions used in rsync
28 /* Establish a proxy connection on an open socket to a web roxy by
29 * using the CONNECT method. */
30 static int establish_proxy_connection(int fd, char *host, int port)
35 snprintf(buffer, sizeof(buffer), "CONNECT %s:%d HTTP/1.0\r\n\r\n", host, port);
36 if (write(fd, buffer, strlen(buffer)) != strlen(buffer)) {
37 rprintf(FERROR, "failed to write to proxy: %s\n",
42 for (cp = buffer; cp < &buffer[sizeof(buffer) - 1]; cp++) {
43 if (read(fd, cp, 1) != 1) {
44 rprintf(FERROR, "failed to read from proxy: %s\n",
57 if (strncmp(buffer, "HTTP/", 5) != 0) {
58 rprintf(FERROR, "bad response from proxy - %s\n",
62 for (cp = &buffer[5]; isdigit(*cp) || (*cp == '.'); cp++)
67 rprintf(FERROR, "bad response from proxy - %s\n",
71 /* throw away the rest of the HTTP header */
73 for (cp = buffer; cp < &buffer[sizeof(buffer) - 1];
75 if (read(fd, cp, 1) != 1) {
76 rprintf(FERROR, "failed to read from proxy: %s\n",
83 if ((cp > buffer) && (*cp == '\n'))
85 if ((cp == buffer) && ((*cp == '\n') || (*cp == '\r')))
92 /* open a socket to a tcp remote host with the specified port
93 based on code from Warren
94 proxy support by Stephen Rothwell */
95 int open_socket_out(char *host, int port, struct in_addr *address)
97 int type = SOCK_STREAM;
98 struct sockaddr_in sock_out;
99 struct sockaddr_in sock;
108 /* if we have a RSYNC_PROXY env variable then redirect our
109 * connetcion via a web proxy at the given address. The format
110 * is hostname:port */
111 h = getenv("RSYNC_PROXY");
112 proxied = (h != NULL) && (*h != '\0');
115 strlcpy(buffer, h, sizeof(buffer));
116 cp = strchr(buffer, ':');
119 "invalid proxy specification: should be HOST:PORT\n");
130 res = socket(PF_INET, type, 0);
135 hp = gethostbyname(h);
137 rprintf(FERROR,"unknown host: %s\n", h);
142 memcpy(&sock_out.sin_addr, hp->h_addr, hp->h_length);
143 sock_out.sin_port = htons(p);
144 sock_out.sin_family = PF_INET;
147 sock.sin_addr = *address;
149 sock.sin_family = hp->h_addrtype;
150 bind(res, (struct sockaddr * ) &sock,sizeof(sock));
153 if (connect(res,(struct sockaddr *)&sock_out,sizeof(sock_out))) {
154 rprintf(FERROR,"failed to connect to %s - %s\n", h, strerror(errno));
159 if (proxied && establish_proxy_connection(res, host, port) != 0) {
168 /****************************************************************************
169 open a socket of the specified type, port and address for incoming data
170 ****************************************************************************/
171 static int open_socket_in(int type, int port, struct in_addr *address)
174 struct sockaddr_in sock;
175 char host_name[MAXHOSTNAMELEN];
179 /* get my host name */
180 if (gethostname(host_name, sizeof(host_name)) == -1) {
181 rprintf(FERROR,"gethostname failed\n");
186 if ((hp = gethostbyname(host_name)) == 0) {
187 rprintf(FERROR,"gethostbyname: Unknown host %s\n",host_name);
191 memset((char *)&sock,0,sizeof(sock));
192 memcpy((char *)&sock.sin_addr,(char *)hp->h_addr, hp->h_length);
193 sock.sin_port = htons(port);
194 sock.sin_family = hp->h_addrtype;
196 sock.sin_addr = *address;
198 sock.sin_addr.s_addr = INADDR_ANY;
200 res = socket(hp->h_addrtype, type, 0);
202 rprintf(FERROR,"socket failed: %s\n",
207 setsockopt(res,SOL_SOCKET,SO_REUSEADDR,(char *)&one,sizeof(one));
209 /* now we've got a socket - we need to bind it */
210 if (bind(res, (struct sockaddr * ) &sock,sizeof(sock)) == -1) {
211 rprintf(FERROR,"bind failed on port %d: %s\n", port,
213 if (errno == EACCES && port < 1024) {
214 rprintf(FERROR, "Note: you must be root to bind "
215 "to low-numbered ports");
226 * Determine if a file descriptor is in fact a socket
228 int is_a_socket(int fd)
234 /* Parameters to getsockopt, setsockopt etc are very
235 * unstandardized across platforms, so don't be surprised if
236 * there are compiler warnings on e.g. SCO OpenSwerver or AIX.
237 * It seems they all eventually get the right idea.
239 * Debian says: ``The fifth argument of getsockopt and
240 * setsockopt is in reality an int [*] (and this is what BSD
241 * 4.* and libc4 and libc5 have). Some POSIX confusion
242 * resulted in the present socklen_t. The draft standard has
243 * not been adopted yet, but glibc2 already follows it and
244 * also has socklen_t [*]. See also accept(2).''
246 * We now return to your regularly scheduled programming. */
247 return(getsockopt(fd, SOL_SOCKET, SO_TYPE, (char *)&v, &l) == 0);
251 void start_accept_loop(int port, int (*fn)(int ))
254 extern struct in_addr socket_address;
256 /* open an incoming socket */
257 s = open_socket_in(SOCK_STREAM, port, &socket_address);
259 exit_cleanup(RERR_SOCKETIO);
261 /* ready to listen */
262 if (listen(s, 5) == -1) {
264 exit_cleanup(RERR_SOCKETIO);
268 /* now accept incoming connections - forking a new process
269 for each incoming connection */
273 struct sockaddr addr;
274 socklen_t in_addrlen = sizeof(addr);
276 /* close log file before the potentially very long select so
277 file can be trimmed by another process instead of growing
284 if (select(s+1, &fds, NULL, NULL, NULL) != 1) {
288 if(!FD_ISSET(s, &fds)) continue;
290 /* See note above prototypes. */
291 fd = accept(s,&addr, &in_addrlen);
293 if (fd == -1) continue;
295 signal(SIGCHLD, SIG_IGN);
297 /* we shouldn't have any children left hanging around
298 but I have had reports that on Digital Unix zombies
299 are produced, so this ensures that they are reaped */
301 while (waitpid(-1, NULL, WNOHANG) > 0);
307 /* open log file in child before possibly giving
319 enum SOCK_OPT_TYPES {OPT_BOOL,OPT_INT,OPT_ON};
328 } socket_options[] = {
329 {"SO_KEEPALIVE", SOL_SOCKET, SO_KEEPALIVE, 0, OPT_BOOL},
330 {"SO_REUSEADDR", SOL_SOCKET, SO_REUSEADDR, 0, OPT_BOOL},
331 {"SO_BROADCAST", SOL_SOCKET, SO_BROADCAST, 0, OPT_BOOL},
333 {"TCP_NODELAY", IPPROTO_TCP, TCP_NODELAY, 0, OPT_BOOL},
335 #ifdef IPTOS_LOWDELAY
336 {"IPTOS_LOWDELAY", IPPROTO_IP, IP_TOS, IPTOS_LOWDELAY, OPT_ON},
338 #ifdef IPTOS_THROUGHPUT
339 {"IPTOS_THROUGHPUT", IPPROTO_IP, IP_TOS, IPTOS_THROUGHPUT, OPT_ON},
342 {"SO_SNDBUF", SOL_SOCKET, SO_SNDBUF, 0, OPT_INT},
345 {"SO_RCVBUF", SOL_SOCKET, SO_RCVBUF, 0, OPT_INT},
348 {"SO_SNDLOWAT", SOL_SOCKET, SO_SNDLOWAT, 0, OPT_INT},
351 {"SO_RCVLOWAT", SOL_SOCKET, SO_RCVLOWAT, 0, OPT_INT},
354 {"SO_SNDTIMEO", SOL_SOCKET, SO_SNDTIMEO, 0, OPT_INT},
357 {"SO_RCVTIMEO", SOL_SOCKET, SO_RCVTIMEO, 0, OPT_INT},
363 /****************************************************************************
364 set user socket options
365 ****************************************************************************/
366 void set_socket_options(int fd, char *options)
369 if (!options || !*options) return;
371 options = strdup(options);
373 if (!options) out_of_memory("set_socket_options");
375 for (tok=strtok(options, " \t,"); tok; tok=strtok(NULL," \t,")) {
381 if ((p = strchr(tok,'='))) {
387 for (i=0;socket_options[i].name;i++)
388 if (strcmp(socket_options[i].name,tok)==0)
391 if (!socket_options[i].name) {
392 rprintf(FERROR,"Unknown socket option %s\n",tok);
396 switch (socket_options[i].opttype) {
399 ret = setsockopt(fd,socket_options[i].level,
400 socket_options[i].option,(char *)&value,sizeof(int));
405 rprintf(FERROR,"syntax error - %s does not take a value\n",tok);
408 int on = socket_options[i].value;
409 ret = setsockopt(fd,socket_options[i].level,
410 socket_options[i].option,(char *)&on,sizeof(int));
416 rprintf(FERROR, "failed to set socket option %s: %s\n", tok,
423 /****************************************************************************
424 become a daemon, discarding the controlling terminal
425 ****************************************************************************/
426 void become_daemon(void)
434 /* detach from the terminal */
439 i = open("/dev/tty", O_RDWR);
441 ioctl(i, (int) TIOCNOTTY, (char *)0);
444 #endif /* TIOCNOTTY */
446 /* make sure that stdin, stdout an stderr don't stuff things
447 up (library functions, for example) */
450 open("/dev/null", O_RDWR);
454 /*******************************************************************
455 return the IP addr of the client as a string
456 ******************************************************************/
457 char *client_addr(int fd)
460 struct sockaddr_in *sockin = (struct sockaddr_in *) (&sa);
461 int length = sizeof(sa);
462 static char addr_buf[100];
463 static int initialised;
465 if (initialised) return addr_buf;
469 if (getpeername(fd, &sa, &length)) {
470 exit_cleanup(RERR_SOCKETIO);
473 strlcpy(addr_buf,(char *)inet_ntoa(sockin->sin_addr), sizeof(addr_buf));
478 /*******************************************************************
479 return the DNS name of the client
480 ******************************************************************/
481 char *client_name(int fd)
484 struct sockaddr_in *sockin = (struct sockaddr_in *) (&sa);
485 socklen_t length = sizeof(sa);
486 static char name_buf[100];
489 char *def = "UNKNOWN";
490 static int initialised;
492 if (initialised) return name_buf;
496 strcpy(name_buf,def);
498 if (getpeername(fd, &sa, &length)) {
499 exit_cleanup(RERR_SOCKETIO);
502 /* Look up the remote host name. */
503 if ((hp = gethostbyaddr((char *) &sockin->sin_addr,
504 sizeof(sockin->sin_addr),
506 strlcpy(name_buf,(char *)hp->h_name,sizeof(name_buf));
510 /* do a forward lookup as well to prevent spoofing */
511 hp = gethostbyname(name_buf);
513 strcpy(name_buf,def);
514 rprintf(FERROR,"reverse name lookup failed\n");
516 for (p=hp->h_addr_list;*p;p++) {
517 if (memcmp(*p, &sockin->sin_addr, hp->h_length) == 0) {
522 strcpy(name_buf,def);
523 rprintf(FERROR,"reverse name lookup mismatch - spoofed address?\n");
530 /*******************************************************************
531 convert a string to an IP address. The string can be a name or
532 dotted decimal number
533 ******************************************************************/
534 struct in_addr *ip_address(const char *str)
536 static struct in_addr ret;
539 /* try as an IP address */
540 if (inet_aton(str, &ret) != 0) {
544 /* otherwise assume it's a network name of some sort and use
546 if ((hp = gethostbyname(str)) == 0) {
547 rprintf(FERROR, "gethostbyname: Unknown host. %s\n",str);
551 if (hp->h_addr == NULL) {
552 rprintf(FERROR, "gethostbyname: host address is invalid for host %s\n",str);
556 if (hp->h_length > sizeof(ret)) {
557 rprintf(FERROR, "gethostbyname: host address is too large\n");
561 memcpy(&ret.s_addr, hp->h_addr, hp->h_length);