[rsync/rsync.git] / socket.c

/* 
   Copyright (C) Andrew Tridgell 1998
   
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.
   
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
   
   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

/*
  socket functions used in rsync 

  */

#include "rsync.h"

/* open a socket to a tcp remote host with the specified port 
   based on code from Warren */
int open_socket_out(char *host, int port)
{
	int type = SOCK_STREAM;
	struct sockaddr_in sock_out;
	int res;
	struct hostent *hp;
  

	res = socket(PF_INET, type, 0);
	if (res == -1) {
		return -1;
	}

	hp = gethostbyname(host);
	if (!hp) {
		rprintf(FERROR,"unknown host: %s\n", host);
		return -1;
	}

	memcpy(&sock_out.sin_addr, hp->h_addr, hp->h_length);
	sock_out.sin_port = htons(port);
	sock_out.sin_family = PF_INET;

	if (connect(res,(struct sockaddr *)&sock_out,sizeof(sock_out))) {
		close(res);
		rprintf(FERROR,"failed to connect to %s - %s\n", host, strerror(errno));
		return -1;
	}

	return res;
}


/****************************************************************************
open a socket of the specified type, port and address for incoming data
****************************************************************************/
static int open_socket_in(int type, int port)
{
	struct hostent *hp;
	struct sockaddr_in sock;
	char host_name[200];
	int res;
	int one=1;

	/* get my host name */
	if (gethostname(host_name, sizeof(host_name)) == -1) { 
		rprintf(FERROR,"gethostname failed\n"); 
		return -1; 
	} 

	/* get host info */
	if ((hp = gethostbyname(host_name)) == 0) {
		rprintf(FERROR,"gethostbyname: Unknown host %s\n",host_name);
		return -1;
	}
  
	memset((char *)&sock,0,sizeof(sock));
	memcpy((char *)&sock.sin_addr,(char *)hp->h_addr, hp->h_length);
	sock.sin_port = htons(port);
	sock.sin_family = hp->h_addrtype;
	sock.sin_addr.s_addr = INADDR_ANY;
	res = socket(hp->h_addrtype, type, 0);
	if (res == -1) { 
		rprintf(FERROR,"socket failed\n"); 
		return -1; 
	}

	setsockopt(res,SOL_SOCKET,SO_REUSEADDR,(char *)&one,sizeof(one));

	/* now we've got a socket - we need to bind it */
	if (bind(res, (struct sockaddr * ) &sock,sizeof(sock)) == -1) { 
		rprintf(FERROR,"bind failed on port %d\n", port);
		close(res); 
		return -1;
	}

	return res;
}


/****************************************************************************
determine if a file descriptor is in fact a socket
****************************************************************************/
int is_a_socket(int fd)
{
  int v,l;
  l = sizeof(int);
  return(getsockopt(fd, SOL_SOCKET, SO_TYPE, (char *)&v, &l) == 0);
}


void start_accept_loop(int port, int (*fn)(int ))
{
	int s;

	/* open an incoming socket */
	s = open_socket_in(SOCK_STREAM, port);
	if (s == -1)
		exit_cleanup(1);

	/* ready to listen */
	if (listen(s, 5) == -1) {
		close(s);
		exit_cleanup(1);
	}


	/* now accept incoming connections - forking a new process
	   for each incoming connection */
	while (1) {
		fd_set fds;
		int fd;
		struct sockaddr addr;
		int in_addrlen = sizeof(addr);

		FD_ZERO(&fds);
		FD_SET(s, &fds);

		if (select(s+1, &fds, NULL, NULL, NULL) != 1) {
			continue;
		}

		if(!FD_ISSET(s, &fds)) continue;

		fd = accept(s,&addr,&in_addrlen);

		if (fd == -1) continue;

		signal(SIGCHLD, SIG_IGN);

		/* we shouldn't have any children left hanging around
		   but I have had reports that on Digital Unix zombies
		   are produced, so this ensures that they are reaped */
#ifdef WNOHANG
		waitpid(-1, NULL, WNOHANG);
#endif

		if (fork()==0) {
			close(s);

			_exit(fn(fd));
		}

		close(fd);
	}
}


enum SOCK_OPT_TYPES {OPT_BOOL,OPT_INT,OPT_ON};

struct
{
  char *name;
  int level;
  int option;
  int value;
  int opttype;
} socket_options[] = {
  {"SO_KEEPALIVE",      SOL_SOCKET,    SO_KEEPALIVE,    0,                 OPT_BOOL},
  {"SO_REUSEADDR",      SOL_SOCKET,    SO_REUSEADDR,    0,                 OPT_BOOL},
  {"SO_BROADCAST",      SOL_SOCKET,    SO_BROADCAST,    0,                 OPT_BOOL},
#ifdef TCP_NODELAY
  {"TCP_NODELAY",       IPPROTO_TCP,   TCP_NODELAY,     0,                 OPT_BOOL},
#endif
#ifdef IPTOS_LOWDELAY
  {"IPTOS_LOWDELAY",    IPPROTO_IP,    IP_TOS,          IPTOS_LOWDELAY,    OPT_ON},
#endif
#ifdef IPTOS_THROUGHPUT
  {"IPTOS_THROUGHPUT",  IPPROTO_IP,    IP_TOS,          IPTOS_THROUGHPUT,  OPT_ON},
#endif
#ifdef SO_SNDBUF
  {"SO_SNDBUF",         SOL_SOCKET,    SO_SNDBUF,       0,                 OPT_INT},
#endif
#ifdef SO_RCVBUF
  {"SO_RCVBUF",         SOL_SOCKET,    SO_RCVBUF,       0,                 OPT_INT},
#endif
#ifdef SO_SNDLOWAT
  {"SO_SNDLOWAT",       SOL_SOCKET,    SO_SNDLOWAT,     0,                 OPT_INT},
#endif
#ifdef SO_RCVLOWAT
  {"SO_RCVLOWAT",       SOL_SOCKET,    SO_RCVLOWAT,     0,                 OPT_INT},
#endif
#ifdef SO_SNDTIMEO
  {"SO_SNDTIMEO",       SOL_SOCKET,    SO_SNDTIMEO,     0,                 OPT_INT},
#endif
#ifdef SO_RCVTIMEO
  {"SO_RCVTIMEO",       SOL_SOCKET,    SO_RCVTIMEO,     0,                 OPT_INT},
#endif
  {NULL,0,0,0,0}};

	
/****************************************************************************
set user socket options
****************************************************************************/
void set_socket_options(int fd, char *options)
{
	char *tok;
	if (!options || !*options) return;

	options = strdup(options);
	
	if (!options) out_of_memory("set_socket_options");

	for (tok=strtok(options, " \t,"); tok; tok=strtok(NULL," \t,")) {
		int ret=0,i;
		int value = 1;
		char *p;
		int got_value = 0;

		if ((p = strchr(tok,'='))) {
			*p = 0;
			value = atoi(p+1);
			got_value = 1;
		}

		for (i=0;socket_options[i].name;i++)
			if (strcmp(socket_options[i].name,tok)==0)
				break;

		if (!socket_options[i].name) {
			rprintf(FERROR,"Unknown socket option %s\n",tok);
			continue;
		}

		switch (socket_options[i].opttype) {
		case OPT_BOOL:
		case OPT_INT:
			ret = setsockopt(fd,socket_options[i].level,
					 socket_options[i].option,(char *)&value,sizeof(int));
			break;
			
		case OPT_ON:
			if (got_value)
				rprintf(FERROR,"syntax error - %s does not take a value\n",tok);

			{
				int on = socket_options[i].value;
				ret = setsockopt(fd,socket_options[i].level,
						 socket_options[i].option,(char *)&on,sizeof(int));
			}
			break;	  
		}
		
		if (ret != 0)
			rprintf(FERROR,"Failed to set socket option %s\n",tok);
	}

	free(options);
}

/****************************************************************************
become a daemon, discarding the controlling terminal
****************************************************************************/
void become_daemon(void)
{
	if (fork())
		_exit(0);

	/* detach from the terminal */
#ifdef HAVE_SETSID
	setsid();
#else
#ifdef TIOCNOTTY
	{
		int i = open("/dev/tty", O_RDWR);
		if (i >= 0) 
			{
				ioctl(i, (int) TIOCNOTTY, (char *)0);      
				close(i);
			}
	}
#endif /* TIOCNOTTY */
#endif
	close(0);
	close(1);
	close(2);
}

/*******************************************************************
 return the IP addr of the client as a string 
 ******************************************************************/
char *client_addr(int fd)
{
	struct sockaddr sa;
	struct sockaddr_in *sockin = (struct sockaddr_in *) (&sa);
	int     length = sizeof(sa);
	static char addr_buf[100];

	if (getpeername(fd, &sa, &length)) {
		exit_cleanup(1);
	}

	strlcpy(addr_buf,(char *)inet_ntoa(sockin->sin_addr), sizeof(addr_buf)-1);

	return addr_buf;
}


/*******************************************************************
 return the DNS name of the client 
 ******************************************************************/
char *client_name(int fd)
{
	struct sockaddr sa;
	struct sockaddr_in *sockin = (struct sockaddr_in *) (&sa);
	int     length = sizeof(sa);
	static char name_buf[100];
	struct hostent *hp;
	char **p;
	char *def = "UNKNOWN";

	strcpy(name_buf,def);

	if (getpeername(fd, &sa, &length)) {
		exit_cleanup(1);
	}

	/* Look up the remote host name. */
	if ((hp = gethostbyaddr((char *) &sockin->sin_addr,
				sizeof(sockin->sin_addr),
				AF_INET))) {
		strlcpy(name_buf,(char *)hp->h_name,sizeof(name_buf) - 1);
	}


	/* do a forward lookup as well to prevent spoofing */
	hp = gethostbyname(name_buf);
	if (!hp) {
		strcpy(name_buf,def);
		rprintf(FERROR,"reverse name lookup failed\n");
	} else {
		for (p=hp->h_addr_list;*p;p++) {
			if (memcmp(*p, &sockin->sin_addr, hp->h_length) == 0) {
				break;
			}
		}
		if (!*p) {
			strcpy(name_buf,def);
			rprintf(FERROR,"reverse name lookup mismatch - spoofed address?\n");
		} 
	}

	return name_buf;
}
Commit	Line	Data
bc2e93eb AT	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
f0fca04e AT	24	#include "rsync.h"
	25
	26	/* open a socket to a tcp remote host with the specified port
	27	based on code from Warren */
bc2e93eb AT	28	int open_socket_out(char *host, int port)
bc2e93eb AT	29	{
f0fca04e AT	30	int type = SOCK_STREAM;
	31	struct sockaddr_in sock_out;
	32	int res;
	33	struct hostent *hp;
	34
	35
	36	res = socket(PF_INET, type, 0);
	37	if (res == -1) {
	38	return -1;
	39	}
	40
	41	hp = gethostbyname(host);
	42	if (!hp) {
	43	rprintf(FERROR,"unknown host: %s\n", host);
	44	return -1;
	45	}
	46
	47	memcpy(&sock_out.sin_addr, hp->h_addr, hp->h_length);
	48	sock_out.sin_port = htons(port);
	49	sock_out.sin_family = PF_INET;
	50
	51	if (connect(res,(struct sockaddr *)&sock_out,sizeof(sock_out))) {
	52	close(res);
	53	rprintf(FERROR,"failed to connect to %s - %s\n", host, strerror(errno));
	54	return -1;
	55	}
	56
	57	return res;
	58	}
	59
	60
	61	/****************************************************************************
	62	open a socket of the specified type, port and address for incoming data
	63	****************************************************************************/
	64	static int open_socket_in(int type, int port)
	65	{
	66	struct hostent *hp;
	67	struct sockaddr_in sock;
	68	char host_name[200];
	69	int res;
	70	int one=1;
	71
	72	/* get my host name */
	73	if (gethostname(host_name, sizeof(host_name)) == -1) {
	74	rprintf(FERROR,"gethostname failed\n");
	75	return -1;
	76	}
	77
	78	/* get host info */
	79	if ((hp = gethostbyname(host_name)) == 0) {
	80	rprintf(FERROR,"gethostbyname: Unknown host %s\n",host_name);
	81	return -1;
	82	}
	83
f5780433	84	memset((char *)&sock,0,sizeof(sock));
f0fca04e AT	85	memcpy((char )&sock.sin_addr,(char )hp->h_addr, hp->h_length);
	86	sock.sin_port = htons(port);
	87	sock.sin_family = hp->h_addrtype;
	88	sock.sin_addr.s_addr = INADDR_ANY;
	89	res = socket(hp->h_addrtype, type, 0);
	90	if (res == -1) {
	91	rprintf(FERROR,"socket failed\n");
	92	return -1;
	93	}
	94
	95	setsockopt(res,SOL_SOCKET,SO_REUSEADDR,(char *)&one,sizeof(one));
	96
	97	/* now we've got a socket - we need to bind it */
	98	if (bind(res, (struct sockaddr * ) &sock,sizeof(sock)) == -1) {
	99	rprintf(FERROR,"bind failed on port %d\n", port);
	100	close(res);
	101	return -1;
	102	}
	103
	104	return res;
	105	}
	106
	107
	108	/****************************************************************************
	109	determine if a file descriptor is in fact a socket
	110	****************************************************************************/
	111	int is_a_socket(int fd)
	112	{
	113	int v,l;
	114	l = sizeof(int);
	115	return(getsockopt(fd, SOL_SOCKET, SO_TYPE, (char *)&v, &l) == 0);
	116	}
	117
	118
8ef4ffd6	119	void start_accept_loop(int port, int (*fn)(int ))
f0fca04e AT	120	{
	121	int s;
	122
f0fca04e AT	123	/* open an incoming socket */
	124	s = open_socket_in(SOCK_STREAM, port);
	125	if (s == -1)
8d9dc9f9	126	exit_cleanup(1);
f0fca04e AT	127
	128	/* ready to listen */
	129	if (listen(s, 5) == -1) {
	130	close(s);
8d9dc9f9	131	exit_cleanup(1);
f0fca04e AT	132	}
	133
	134
	135	/* now accept incoming connections - forking a new process
	136	for each incoming connection */
	137	while (1) {
	138	fd_set fds;
	139	int fd;
	140	struct sockaddr addr;
	141	int in_addrlen = sizeof(addr);
	142
	143	FD_ZERO(&fds);
	144	FD_SET(s, &fds);
	145
	146	if (select(s+1, &fds, NULL, NULL, NULL) != 1) {
	147	continue;
	148	}
	149
	150	if(!FD_ISSET(s, &fds)) continue;
	151
	152	fd = accept(s,&addr,&in_addrlen);
	153
	154	if (fd == -1) continue;
	155
31f440e6 AT	156	signal(SIGCHLD, SIG_IGN);
	157
	158	/* we shouldn't have any children left hanging around
	159	but I have had reports that on Digital Unix zombies
	160	are produced, so this ensures that they are reaped */
	161	#ifdef WNOHANG
	162	waitpid(-1, NULL, WNOHANG);
	163	#endif
	164
f0fca04e AT	165	if (fork()==0) {
	166	close(s);
	167
	168	_exit(fn(fd));
	169	}
	170
	171	close(fd);
	172	}
f0fca04e AT	173	}
	174
	175
	176	enum SOCK_OPT_TYPES {OPT_BOOL,OPT_INT,OPT_ON};
	177
	178	struct
	179	{
	180	char *name;
	181	int level;
	182	int option;
	183	int value;
	184	int opttype;
	185	} socket_options[] = {
	186	{"SO_KEEPALIVE", SOL_SOCKET, SO_KEEPALIVE, 0, OPT_BOOL},
	187	{"SO_REUSEADDR", SOL_SOCKET, SO_REUSEADDR, 0, OPT_BOOL},
	188	{"SO_BROADCAST", SOL_SOCKET, SO_BROADCAST, 0, OPT_BOOL},
	189	#ifdef TCP_NODELAY
	190	{"TCP_NODELAY", IPPROTO_TCP, TCP_NODELAY, 0, OPT_BOOL},
	191	#endif
	192	#ifdef IPTOS_LOWDELAY
	193	{"IPTOS_LOWDELAY", IPPROTO_IP, IP_TOS, IPTOS_LOWDELAY, OPT_ON},
	194	#endif
	195	#ifdef IPTOS_THROUGHPUT
	196	{"IPTOS_THROUGHPUT", IPPROTO_IP, IP_TOS, IPTOS_THROUGHPUT, OPT_ON},
	197	#endif
	198	#ifdef SO_SNDBUF
	199	{"SO_SNDBUF", SOL_SOCKET, SO_SNDBUF, 0, OPT_INT},
	200	#endif
	201	#ifdef SO_RCVBUF
	202	{"SO_RCVBUF", SOL_SOCKET, SO_RCVBUF, 0, OPT_INT},
	203	#endif
	204	#ifdef SO_SNDLOWAT
	205	{"SO_SNDLOWAT", SOL_SOCKET, SO_SNDLOWAT, 0, OPT_INT},
	206	#endif
	207	#ifdef SO_RCVLOWAT
	208	{"SO_RCVLOWAT", SOL_SOCKET, SO_RCVLOWAT, 0, OPT_INT},
	209	#endif
	210	#ifdef SO_SNDTIMEO
	211	{"SO_SNDTIMEO", SOL_SOCKET, SO_SNDTIMEO, 0, OPT_INT},
	212	#endif
	213	#ifdef SO_RCVTIMEO
	214	{"SO_RCVTIMEO", SOL_SOCKET, SO_RCVTIMEO, 0, OPT_INT},
	215	#endif
	216	{NULL,0,0,0,0}};
	217
	218
	219
	220	/****************************************************************************
	221	set user socket options
	222	****************************************************************************/
	223	void set_socket_options(int fd, char *options)
	224	{
	225	char *tok;
a6801c39 AT	226	if (!options \|\| !*options) return;
a6801c39 AT	227
f0fca04e AT	228	options = strdup(options);
	229
	230	if (!options) out_of_memory("set_socket_options");
	231
	232	for (tok=strtok(options, " \t,"); tok; tok=strtok(NULL," \t,")) {
	233	int ret=0,i;
	234	int value = 1;
	235	char *p;
	236	int got_value = 0;
	237
	238	if ((p = strchr(tok,'='))) {
	239	*p = 0;
	240	value = atoi(p+1);
	241	got_value = 1;
	242	}
	243
	244	for (i=0;socket_options[i].name;i++)
	245	if (strcmp(socket_options[i].name,tok)==0)
	246	break;
	247
	248	if (!socket_options[i].name) {
	249	rprintf(FERROR,"Unknown socket option %s\n",tok);
	250	continue;
	251	}
	252
	253	switch (socket_options[i].opttype) {
	254	case OPT_BOOL:
	255	case OPT_INT:
	256	ret = setsockopt(fd,socket_options[i].level,
	257	socket_options[i].option,(char *)&value,sizeof(int));
	258	break;
	259
	260	case OPT_ON:
	261	if (got_value)
	262	rprintf(FERROR,"syntax error - %s does not take a value\n",tok);
	263
	264	{
	265	int on = socket_options[i].value;
	266	ret = setsockopt(fd,socket_options[i].level,
	267	socket_options[i].option,(char *)&on,sizeof(int));
	268	}
	269	break;
	270	}
	271
	272	if (ret != 0)
	273	rprintf(FERROR,"Failed to set socket option %s\n",tok);
	274	}
	275
	276	free(options);
	277	}
	278
	279	/****************************************************************************
	280	become a daemon, discarding the controlling terminal
	281	****************************************************************************/
	282	void become_daemon(void)
	283	{
	284	if (fork())
	285	_exit(0);
	286
	287	/* detach from the terminal */
	288	#ifdef HAVE_SETSID
	289	setsid();
	290	#else
	291	#ifdef TIOCNOTTY
292	{
293	int i = open("/dev/tty", O_RDWR);
294	if (i >= 0)
295	{
296	ioctl(i, (int) TIOCNOTTY, (char *)0);
297	close(i);
298	}
299	}
300	#endif /* TIOCNOTTY */
301	#endif
302	close(0);
303	close(1);
304	close(2);
bc2e93eb	305	}
ff8b29b8 AT	306
	307	/*******************************************************************
	308	return the IP addr of the client as a string
	309	******************************************************************/
	310	char *client_addr(int fd)
	311	{
	312	struct sockaddr sa;
	313	struct sockaddr_in sockin = (struct sockaddr_in ) (&sa);
	314	int length = sizeof(sa);
	315	static char addr_buf[100];
	316
	317	if (getpeername(fd, &sa, &length)) {
8d9dc9f9	318	exit_cleanup(1);
ff8b29b8 AT	319	}
	320
	321	strlcpy(addr_buf,(char *)inet_ntoa(sockin->sin_addr), sizeof(addr_buf)-1);
	322
	323	return addr_buf;
	324	}
	325
	326
	327	/*******************************************************************
	328	return the DNS name of the client
	329	******************************************************************/
	330	char *client_name(int fd)
	331	{
	332	struct sockaddr sa;
	333	struct sockaddr_in sockin = (struct sockaddr_in ) (&sa);
	334	int length = sizeof(sa);
	335	static char name_buf[100];
	336	struct hostent *hp;
de5fb374 AT	337	char **p;
de5fb374 AT	338	char *def = "UNKNOWN";
ff8b29b8	339
de5fb374	340	strcpy(name_buf,def);
ff8b29b8 AT	341
ff8b29b8 AT	342	if (getpeername(fd, &sa, &length)) {
8d9dc9f9	343	exit_cleanup(1);
ff8b29b8 AT	344	}
	345
	346	/* Look up the remote host name. */
	347	if ((hp = gethostbyaddr((char *) &sockin->sin_addr,
	348	sizeof(sockin->sin_addr),
	349	AF_INET))) {
	350	strlcpy(name_buf,(char *)hp->h_name,sizeof(name_buf) - 1);
	351	}
	352
de5fb374 AT	353
	354	/* do a forward lookup as well to prevent spoofing */
	355	hp = gethostbyname(name_buf);
	356	if (!hp) {
	357	strcpy(name_buf,def);
	358	rprintf(FERROR,"reverse name lookup failed\n");
	359	} else {
	360	for (p=hp->h_addr_list;*p;p++) {
	361	if (memcmp(*p, &sockin->sin_addr, hp->h_length) == 0) {
	362	break;
	363	}
	364	}
	365	if (!*p) {
	366	strcpy(name_buf,def);
	367	rprintf(FERROR,"reverse name lookup mismatch - spoofed address?\n");
	368	}
	369	}
	370
ff8b29b8 AT	371	return name_buf;
ff8b29b8 AT	372	}