[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"


/* establish a proxy connection on an open socket to a web roxy by using the CONNECT
   method */
static int establish_proxy_connection(int fd, char *host, int port)
{
	char buffer[1024];
	char *cp;

	slprintf(buffer, sizeof(buffer), "CONNECT %s:%d HTTP/1.0\r\n\r\n", host, port);
	if (write(fd, buffer, strlen(buffer)) != strlen(buffer)) {
		rprintf(FERROR, "failed to write to proxy - %s\n",
			strerror(errno));
		return -1;
	}

	for (cp = buffer; cp < &buffer[sizeof(buffer) - 1]; cp++) {
		if (read(fd, cp, 1) != 1) {
			rprintf(FERROR, "failed to read from proxy\n");
			return -1;
		}
		if (*cp == '\n')
			break;
	}

	if (*cp != '\n')
		cp++;
	*cp-- = '\0';
	if (*cp == '\r')
		*cp = '\0';
	if (strncmp(buffer, "HTTP/", 5) != 0) {
		rprintf(FERROR, "bad response from proxy - %s\n",
			buffer);
		return -1;
	}
	for (cp = &buffer[5]; isdigit(*cp) || (*cp == '.'); cp++)
		;
	while (*cp == ' ')
		cp++;
	if (*cp != '2') {
		rprintf(FERROR, "bad response from proxy - %s\n",
			buffer);
		return -1;
	}
	/* throw away the rest of the HTTP header */
	while (1) {
		for (cp = buffer; cp < &buffer[sizeof(buffer) - 1];
		     cp++) {
			if (read(fd, cp, 1) != 1) {
				rprintf(FERROR, "failed to read from proxy\n");
				return -1;
			}
			if (*cp == '\n')
				break;
		}
		if ((cp > buffer) && (*cp == '\n'))
			cp--;
		if ((cp == buffer) && ((*cp == '\n') || (*cp == '\r')))
			break;
	}
	return 0;
}


/* open a socket to a tcp remote host with the specified port 
   based on code from Warren
   proxy support by Stephen Rothwell */
int open_socket_out(char *host, int port, struct in_addr *address)
{
	int type = SOCK_STREAM;
	struct sockaddr_in sock_out;
	struct sockaddr_in sock;
	int res;
	struct hostent *hp;
	char *h;
	unsigned p;
	int proxied = 0;
	char buffer[1024];
	char *cp;

	/* if we have a RSYNC_PROXY env variable then redirect our connetcion via a web proxy
	   at the given address. The format is hostname:port */
	h = getenv("RSYNC_PROXY");
	proxied = (h != NULL) && (*h != '\0');

	if (proxied) {
		strlcpy(buffer, h, sizeof(buffer));
		cp = strchr(buffer, ':');
		if (cp == NULL) {
			rprintf(FERROR, "invalid proxy specification\n");
			return -1;
		}
		*cp++ = '\0';
		p = atoi(cp);
		h = buffer;
	} else {
		h = host;
		p = port;
	}

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

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

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

	if (address) {
		sock.sin_addr = *address;
		sock.sin_port = 0;
		sock.sin_family = hp->h_addrtype;
		bind(res, (struct sockaddr * ) &sock,sizeof(sock));
	}

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

	if (proxied && establish_proxy_connection(res, host, port) != 0) {
		close(res);
		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 in_addr *address)
{
	struct hostent *hp;
	struct sockaddr_in sock;
	char host_name[MAXHOSTNAMELEN];
	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;
	if (address) {
		sock.sin_addr = *address;
	} else {
		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;
	extern struct in_addr socket_address;

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

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


	/* 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
                while (waitpid(-1, NULL, WNOHANG) > 0);
#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)
{
	int i;

	if (fork()) {
		_exit(0);
	}

	/* detach from the terminal */
#ifdef HAVE_SETSID
	setsid();
#else
#ifdef TIOCNOTTY
	i = open("/dev/tty", O_RDWR);
	if (i >= 0) {
		ioctl(i, (int) TIOCNOTTY, (char *)0);      
		close(i);
	}
#endif /* TIOCNOTTY */
#endif
	/* make sure that stdin, stdout an stderr don't stuff things
           up (library functions, for example) */
	for (i=0;i<3;i++) {
		close(i); 
		open("/dev/null", O_RDWR);
	}
}

/*******************************************************************
 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];
	static int initialised;

	if (initialised) return addr_buf;

	initialised = 1;

	if (getpeername(fd, &sa, &length)) {
		exit_cleanup(RERR_SOCKETIO);
	}
	
	strlcpy(addr_buf,(char *)inet_ntoa(sockin->sin_addr), sizeof(addr_buf));
	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";
	static int initialised;

	if (initialised) return name_buf;

	initialised = 1;

	strcpy(name_buf,def);

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

	/* 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));
	}


	/* 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;
}

/*******************************************************************
convert a string to an IP address. The string can be a name or
dotted decimal number
  ******************************************************************/
struct in_addr *ip_address(const char *str)
{
	static struct in_addr ret;
	struct hostent *hp;

	/* try as an IP address */
	if (inet_aton(str, &ret) != 0) {
		return &ret;
	}

	/* otherwise assume it's a network name of some sort and use 
	   gethostbyname */
	if ((hp = gethostbyname(str)) == 0) {
		rprintf(FERROR, "gethostbyname: Unknown host. %s\n",str);
		return NULL;
	}

	if (hp->h_addr == NULL) {
		rprintf(FERROR, "gethostbyname: host address is invalid for host %s\n",str);
		return NULL;
	}

	if (hp->h_length > sizeof(ret)) {
		rprintf(FERROR, "gethostbyname: host address is too large\n");
		return NULL;
	}

	memcpy(&ret.s_addr, hp->h_addr, hp->h_length);

	return(&ret);
}
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"
f0fca04e AT	25
4c3b4b25 AT	26
	27	/* establish a proxy connection on an open socket to a web roxy by using the CONNECT
	28	method */
	29	static 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
4c3b4b25 AT	90	based on code from Warren
4c3b4b25 AT	91	proxy support by Stephen Rothwell */
e30f0657	92	int open_socket_out(char host, int port, struct in_addr address)
bc2e93eb	93	{
f0fca04e AT	94	int type = SOCK_STREAM;
f0fca04e AT	95	struct sockaddr_in sock_out;
e30f0657	96	struct sockaddr_in sock;
f0fca04e AT	97	int res;
f0fca04e AT	98	struct hostent *hp;
4c3b4b25 AT	99	char *h;
	100	unsigned p;
	101	int proxied = 0;
	102	char buffer[1024];
	103	char *cp;
	104
	105	/* if we have a RSYNC_PROXY env variable then redirect our connetcion via a web proxy
	106	at the given address. The format is hostname:port */
	107	h = getenv("RSYNC_PROXY");
	108	proxied = (h != NULL) && (*h != '\0');
	109
	110	if (proxied) {
	111	strlcpy(buffer, h, sizeof(buffer));
	112	cp = strchr(buffer, ':');
	113	if (cp == NULL) {
	114	rprintf(FERROR, "invalid proxy specification\n");
	115	return -1;
	116	}
	117	*cp++ = '\0';
	118	p = atoi(cp);
	119	h = buffer;
	120	} else {
	121	h = host;
	122	p = port;
	123	}
f0fca04e AT	124
	125	res = socket(PF_INET, type, 0);
	126	if (res == -1) {
	127	return -1;
	128	}
	129
4c3b4b25	130	hp = gethostbyname(h);
f0fca04e	131	if (!hp) {
4c3b4b25 AT	132	rprintf(FERROR,"unknown host: %s\n", h);
4c3b4b25 AT	133	close(res);
f0fca04e AT	134	return -1;
	135	}
	136
	137	memcpy(&sock_out.sin_addr, hp->h_addr, hp->h_length);
4c3b4b25	138	sock_out.sin_port = htons(p);
f0fca04e AT	139	sock_out.sin_family = PF_INET;
f0fca04e AT	140
e30f0657 AT	141	if (address) {
	142	sock.sin_addr = *address;
	143	sock.sin_port = 0;
	144	sock.sin_family = hp->h_addrtype;
	145	bind(res, (struct sockaddr * ) &sock,sizeof(sock));
	146	}
	147
f0fca04e	148	if (connect(res,(struct sockaddr *)&sock_out,sizeof(sock_out))) {
4c3b4b25 AT	149	rprintf(FERROR,"failed to connect to %s - %s\n", h, strerror(errno));
	150	close(res);
	151	return -1;
	152	}
	153
	154	if (proxied && establish_proxy_connection(res, host, port) != 0) {
f0fca04e	155	close(res);
f0fca04e AT	156	return -1;
	157	}
	158
	159	return res;
	160	}
	161
	162
	163	/****************************************************************************
	164	open a socket of the specified type, port and address for incoming data
	165	****************************************************************************/
5c9730a4	166	static int open_socket_in(int type, int port, struct in_addr *address)
f0fca04e AT	167	{
	168	struct hostent *hp;
	169	struct sockaddr_in sock;
d41c7d02	170	char host_name[MAXHOSTNAMELEN];
f0fca04e AT	171	int res;
	172	int one=1;
	173
	174	/* get my host name */
	175	if (gethostname(host_name, sizeof(host_name)) == -1) {
	176	rprintf(FERROR,"gethostname failed\n");
	177	return -1;
	178	}
	179
	180	/* get host info */
	181	if ((hp = gethostbyname(host_name)) == 0) {
	182	rprintf(FERROR,"gethostbyname: Unknown host %s\n",host_name);
	183	return -1;
	184	}
	185
f5780433	186	memset((char *)&sock,0,sizeof(sock));
f0fca04e AT	187	memcpy((char )&sock.sin_addr,(char )hp->h_addr, hp->h_length);
	188	sock.sin_port = htons(port);
	189	sock.sin_family = hp->h_addrtype;
5c9730a4 AT	190	if (address) {
	191	sock.sin_addr = *address;
	192	} else {
	193	sock.sin_addr.s_addr = INADDR_ANY;
	194	}
f0fca04e AT	195	res = socket(hp->h_addrtype, type, 0);
	196	if (res == -1) {
	197	rprintf(FERROR,"socket failed\n");
	198	return -1;
	199	}
	200
	201	setsockopt(res,SOL_SOCKET,SO_REUSEADDR,(char *)&one,sizeof(one));
	202
	203	/* now we've got a socket - we need to bind it */
	204	if (bind(res, (struct sockaddr * ) &sock,sizeof(sock)) == -1) {
	205	rprintf(FERROR,"bind failed on port %d\n", port);
	206	close(res);
	207	return -1;
	208	}
	209
	210	return res;
	211	}
	212
	213
	214	/****************************************************************************
	215	determine if a file descriptor is in fact a socket
	216	****************************************************************************/
	217	int is_a_socket(int fd)
	218	{
3eb38818 AT	219	int v,l;
	220	l = sizeof(int);
	221	return(getsockopt(fd, SOL_SOCKET, SO_TYPE, (char *)&v, &l) == 0);
f0fca04e AT	222	}
	223
	224
8ef4ffd6	225	void start_accept_loop(int port, int (*fn)(int ))
f0fca04e AT	226	{
f0fca04e AT	227	int s;
5c9730a4	228	extern struct in_addr socket_address;
f0fca04e	229
f0fca04e	230	/* open an incoming socket */
5c9730a4	231	s = open_socket_in(SOCK_STREAM, port, &socket_address);
f0fca04e	232	if (s == -1)
65417579	233	exit_cleanup(RERR_SOCKETIO);
f0fca04e AT	234
	235	/* ready to listen */
	236	if (listen(s, 5) == -1) {
	237	close(s);
65417579	238	exit_cleanup(RERR_SOCKETIO);
f0fca04e AT	239	}
	240
	241
	242	/* now accept incoming connections - forking a new process
	243	for each incoming connection */
	244	while (1) {
	245	fd_set fds;
	246	int fd;
	247	struct sockaddr addr;
	248	int in_addrlen = sizeof(addr);
	249
	250	FD_ZERO(&fds);
	251	FD_SET(s, &fds);
	252
	253	if (select(s+1, &fds, NULL, NULL, NULL) != 1) {
	254	continue;
	255	}
	256
	257	if(!FD_ISSET(s, &fds)) continue;
	258
	259	fd = accept(s,&addr,&in_addrlen);
	260
	261	if (fd == -1) continue;
	262
31f440e6 AT	263	signal(SIGCHLD, SIG_IGN);
	264
	265	/* we shouldn't have any children left hanging around
	266	but I have had reports that on Digital Unix zombies
	267	are produced, so this ensures that they are reaped */
	268	#ifdef WNOHANG
0503f060	269	while (waitpid(-1, NULL, WNOHANG) > 0);
31f440e6 AT	270	#endif
31f440e6 AT	271
f0fca04e AT	272	if (fork()==0) {
	273	close(s);
	274
	275	_exit(fn(fd));
	276	}
	277
	278	close(fd);
	279	}
f0fca04e AT	280	}
	281
	282
	283	enum SOCK_OPT_TYPES {OPT_BOOL,OPT_INT,OPT_ON};
	284
	285	struct
	286	{
	287	char *name;
	288	int level;
	289	int option;
	290	int value;
	291	int opttype;
	292	} socket_options[] = {
	293	{"SO_KEEPALIVE", SOL_SOCKET, SO_KEEPALIVE, 0, OPT_BOOL},
	294	{"SO_REUSEADDR", SOL_SOCKET, SO_REUSEADDR, 0, OPT_BOOL},
	295	{"SO_BROADCAST", SOL_SOCKET, SO_BROADCAST, 0, OPT_BOOL},
	296	#ifdef TCP_NODELAY
	297	{"TCP_NODELAY", IPPROTO_TCP, TCP_NODELAY, 0, OPT_BOOL},
	298	#endif
	299	#ifdef IPTOS_LOWDELAY
	300	{"IPTOS_LOWDELAY", IPPROTO_IP, IP_TOS, IPTOS_LOWDELAY, OPT_ON},
	301	#endif
	302	#ifdef IPTOS_THROUGHPUT
	303	{"IPTOS_THROUGHPUT", IPPROTO_IP, IP_TOS, IPTOS_THROUGHPUT, OPT_ON},
	304	#endif
	305	#ifdef SO_SNDBUF
	306	{"SO_SNDBUF", SOL_SOCKET, SO_SNDBUF, 0, OPT_INT},
	307	#endif
	308	#ifdef SO_RCVBUF
	309	{"SO_RCVBUF", SOL_SOCKET, SO_RCVBUF, 0, OPT_INT},
	310	#endif
	311	#ifdef SO_SNDLOWAT
	312	{"SO_SNDLOWAT", SOL_SOCKET, SO_SNDLOWAT, 0, OPT_INT},
	313	#endif
	314	#ifdef SO_RCVLOWAT
	315	{"SO_RCVLOWAT", SOL_SOCKET, SO_RCVLOWAT, 0, OPT_INT},
	316	#endif
	317	#ifdef SO_SNDTIMEO
	318	{"SO_SNDTIMEO", SOL_SOCKET, SO_SNDTIMEO, 0, OPT_INT},
	319	#endif
	320	#ifdef SO_RCVTIMEO
	321	{"SO_RCVTIMEO", SOL_SOCKET, SO_RCVTIMEO, 0, OPT_INT},
	322	#endif
	323	{NULL,0,0,0,0}};
	324
	325
	326
	327	/****************************************************************************
	328	set user socket options
	329	****************************************************************************/
	330	void set_socket_options(int fd, char *options)
	331	{
	332	char *tok;
a6801c39 AT	333	if (!options \|\| !*options) return;
a6801c39 AT	334
f0fca04e AT	335	options = strdup(options);
	336
	337	if (!options) out_of_memory("set_socket_options");
	338
	339	for (tok=strtok(options, " \t,"); tok; tok=strtok(NULL," \t,")) {
	340	int ret=0,i;
	341	int value = 1;
	342	char *p;
	343	int got_value = 0;
	344
	345	if ((p = strchr(tok,'='))) {
	346	*p = 0;
	347	value = atoi(p+1);
	348	got_value = 1;
	349	}
	350
	351	for (i=0;socket_options[i].name;i++)
	352	if (strcmp(socket_options[i].name,tok)==0)
	353	break;
	354
	355	if (!socket_options[i].name) {
	356	rprintf(FERROR,"Unknown socket option %s\n",tok);
	357	continue;
	358	}
	359
	360	switch (socket_options[i].opttype) {
	361	case OPT_BOOL:
	362	case OPT_INT:
	363	ret = setsockopt(fd,socket_options[i].level,
	364	socket_options[i].option,(char *)&value,sizeof(int));
	365	break;
	366
	367	case OPT_ON:
	368	if (got_value)
	369	rprintf(FERROR,"syntax error - %s does not take a value\n",tok);
	370
	371	{
	372	int on = socket_options[i].value;
	373	ret = setsockopt(fd,socket_options[i].level,
	374	socket_options[i].option,(char *)&on,sizeof(int));
	375	}
	376	break;
	377	}
	378
	379	if (ret != 0)
	380	rprintf(FERROR,"Failed to set socket option %s\n",tok);
	381	}
	382
	383	free(options);
	384	}
	385
	386	/****************************************************************************
	387	become a daemon, discarding the controlling terminal
	388	****************************************************************************/
	389	void become_daemon(void)
	390	{
b11ed3b1 AT	391	int i;
b11ed3b1 AT	392
c46ded46	393	if (fork()) {
f0fca04e	394	_exit(0);
c46ded46	395	}
f0fca04e AT	396
	397	/* detach from the terminal */
	398	#ifdef HAVE_SETSID
	399	setsid();
	400	#else
	401	#ifdef TIOCNOTTY
c46ded46 AT	402	i = open("/dev/tty", O_RDWR);
	403	if (i >= 0) {
	404	ioctl(i, (int) TIOCNOTTY, (char *)0);
	405	close(i);
f0fca04e AT	406	}
	407	#endif /* TIOCNOTTY */
	408	#endif
b11ed3b1 AT	409	/* make sure that stdin, stdout an stderr don't stuff things
	410	up (library functions, for example) */
	411	for (i=0;i<3;i++) {
	412	close(i);
	413	open("/dev/null", O_RDWR);
	414	}
bc2e93eb	415	}
ff8b29b8 AT	416
	417	/*******************************************************************
	418	return the IP addr of the client as a string
	419	******************************************************************/
	420	char *client_addr(int fd)
	421	{
	422	struct sockaddr sa;
	423	struct sockaddr_in sockin = (struct sockaddr_in ) (&sa);
	424	int length = sizeof(sa);
	425	static char addr_buf[100];
11a5a3c7 AT	426	static int initialised;
	427
	428	if (initialised) return addr_buf;
	429
	430	initialised = 1;
ff8b29b8 AT	431
ff8b29b8 AT	432	if (getpeername(fd, &sa, &length)) {
65417579	433	exit_cleanup(RERR_SOCKETIO);
ff8b29b8	434	}
11a5a3c7	435
37f9805d	436	strlcpy(addr_buf,(char *)inet_ntoa(sockin->sin_addr), sizeof(addr_buf));
ff8b29b8 AT	437	return addr_buf;
	438	}
	439
	440
	441	/*******************************************************************
	442	return the DNS name of the client
	443	******************************************************************/
	444	char *client_name(int fd)
	445	{
	446	struct sockaddr sa;
	447	struct sockaddr_in sockin = (struct sockaddr_in ) (&sa);
	448	int length = sizeof(sa);
	449	static char name_buf[100];
	450	struct hostent *hp;
de5fb374 AT	451	char **p;
de5fb374 AT	452	char *def = "UNKNOWN";
11a5a3c7 AT	453	static int initialised;
	454
	455	if (initialised) return name_buf;
	456
	457	initialised = 1;
ff8b29b8	458
de5fb374	459	strcpy(name_buf,def);
ff8b29b8 AT	460
ff8b29b8 AT	461	if (getpeername(fd, &sa, &length)) {
65417579	462	exit_cleanup(RERR_SOCKETIO);
ff8b29b8 AT	463	}
	464
	465	/* Look up the remote host name. */
	466	if ((hp = gethostbyaddr((char *) &sockin->sin_addr,
	467	sizeof(sockin->sin_addr),
	468	AF_INET))) {
37f9805d	469	strlcpy(name_buf,(char *)hp->h_name,sizeof(name_buf));
ff8b29b8 AT	470	}
ff8b29b8 AT	471
de5fb374 AT	472
	473	/* do a forward lookup as well to prevent spoofing */
	474	hp = gethostbyname(name_buf);
	475	if (!hp) {
	476	strcpy(name_buf,def);
	477	rprintf(FERROR,"reverse name lookup failed\n");
	478	} else {
	479	for (p=hp->h_addr_list;*p;p++) {
	480	if (memcmp(*p, &sockin->sin_addr, hp->h_length) == 0) {
	481	break;
	482	}
	483	}
	484	if (!*p) {
	485	strcpy(name_buf,def);
	486	rprintf(FERROR,"reverse name lookup mismatch - spoofed address?\n");
	487	}
	488	}
	489
ff8b29b8 AT	490	return name_buf;
ff8b29b8 AT	491	}
5c9730a4 AT	492
	493	/*******************************************************************
	494	convert a string to an IP address. The string can be a name or
	495	dotted decimal number
	496	******************************************************************/
	497	struct in_addr ip_address(const char str)
	498	{
	499	static struct in_addr ret;
	500	struct hostent *hp;
	501
	502	/* try as an IP address */
	503	if (inet_aton(str, &ret) != 0) {
	504	return &ret;
	505	}
	506
	507	/* otherwise assume it's a network name of some sort and use
	508	gethostbyname */
	509	if ((hp = gethostbyname(str)) == 0) {
	510	rprintf(FERROR, "gethostbyname: Unknown host. %s\n",str);
	511	return NULL;
	512	}
	513
	514	if (hp->h_addr == NULL) {
	515	rprintf(FERROR, "gethostbyname: host address is invalid for host %s\n",str);
	516	return NULL;
	517	}
	518
	519	if (hp->h_length > sizeof(ret)) {
	520	rprintf(FERROR, "gethostbyname: host address is too large\n");
	521	return NULL;
	522	}
	523
	524	memcpy(&ret.s_addr, hp->h_addr, hp->h_length);
	525
	526	return(&ret);
	527	}