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/*
* Socket functions used in rsync.
*
* Copyright (C) 1992-2001 Andrew Tridgell <tridge@samba.org>
* Copyright (C) 2001, 2002 Martin Pool <mbp@samba.org>
* Copyright (C) 2003-2014 Wayne Davison
*
* 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 3 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, visit the http://fsf.org website.
*/
/* This file is now converted to use the new-style getaddrinfo()
* interface, which supports IPv6 but is also supported on recent
* IPv4-only machines. On systems that don't have that interface, we
* emulate it using the KAME implementation. */
#include "rsync.h"
#include "itypes.h"
#ifdef HAVE_NETINET_IN_SYSTM_H
#include <netinet/in_systm.h>
#endif
#ifdef HAVE_NETINET_IP_H
#include <netinet/ip.h>
#endif
#include <netinet/tcp.h>
extern char *bind_address;
extern char *sockopts;
extern int default_af_hint;
extern int connect_timeout;
#ifdef HAVE_SIGACTION
static struct sigaction sigact;
#endif
static int sock_exec(const char *prog);
/* Establish a proxy connection on an open socket to a web proxy by using the
* CONNECT method. If proxy_user and proxy_pass are not NULL, they are used to
* authenticate to the proxy using the "Basic" proxy-authorization protocol. */
static int establish_proxy_connection(int fd, char *host, int port,
char *proxy_user, char *proxy_pass)
{
char *cp, buffer[1024];
char *authhdr, authbuf[1024];
int len;
if (proxy_user && proxy_pass) {
stringjoin(buffer, sizeof buffer,
proxy_user, ":", proxy_pass, NULL);
len = strlen(buffer);
if ((len*8 + 5) / 6 >= (int)sizeof authbuf - 3) {
rprintf(FERROR,
"authentication information is too long\n");
return -1;
}
base64_encode(buffer, len, authbuf, 1);
authhdr = "\r\nProxy-Authorization: Basic ";
} else {
*authbuf = '\0';
authhdr = "";
}
snprintf(buffer, sizeof buffer, "CONNECT %s:%d HTTP/1.0%s%s\r\n\r\n",
host, port, authhdr, authbuf);
len = strlen(buffer);
if (write(fd, buffer, len) != len) {
rsyserr(FERROR, errno, "failed to write to proxy");
return -1;
}
for (cp = buffer; cp < &buffer[sizeof buffer - 1]; cp++) {
if (read(fd, cp, 1) != 1) {
rsyserr(FERROR, errno, "failed to read from proxy");
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) {
rsyserr(FERROR, errno,
"failed to read from proxy");
return -1;
}
if (*cp == '\n')
break;
}
if (cp > buffer && *cp == '\n')
cp--;
if (cp == buffer && (*cp == '\n' || *cp == '\r'))
break;
}
return 0;
}
/* Try to set the local address for a newly-created socket.
* Return -1 if this fails. */
int try_bind_local(int s, int ai_family, int ai_socktype,
const char *bind_addr)
{
int error;
struct addrinfo bhints, *bres_all, *r;
memset(&bhints, 0, sizeof bhints);
bhints.ai_family = ai_family;
bhints.ai_socktype = ai_socktype;
bhints.ai_flags = AI_PASSIVE;
if ((error = getaddrinfo(bind_addr, NULL, &bhints, &bres_all))) {
rprintf(FERROR, RSYNC_NAME ": getaddrinfo %s: %s\n",
bind_addr, gai_strerror(error));
return -1;
}
for (r = bres_all; r; r = r->ai_next) {
if (bind(s, r->ai_addr, r->ai_addrlen) == -1)
continue;
freeaddrinfo(bres_all);
return s;
}
/* no error message; there might be some problem that allows
* creation of the socket but not binding, perhaps if the
* machine has no ipv6 address of this name. */
freeaddrinfo(bres_all);
return -1;
}
/* connect() timeout handler based on alarm() */
static RETSIGTYPE contimeout_handler(UNUSED(int val))
{
connect_timeout = -1;
}
/* Open a socket to a tcp remote host with the specified port.
*
* Based on code from Warren. Proxy support by Stephen Rothwell.
* getaddrinfo() rewrite contributed by KAME.net.
*
* Now that we support IPv6 we need to look up the remote machine's address
* first, using af_hint to set a preference for the type of address. Then
* depending on whether it has v4 or v6 addresses we try to open a connection.
*
* The loop allows for machines with some addresses which may not be reachable,
* perhaps because we can't e.g. route ipv6 to that network but we can get ip4
* packets through.
*
* bind_addr: local address to use. Normally NULL to bind the wildcard address.
*
* af_hint: address family, e.g. AF_INET or AF_INET6. */
int open_socket_out(char *host, int port, const char *bind_addr,
int af_hint)
{
int type = SOCK_STREAM;
int error, s, j, addr_cnt, *errnos;
struct addrinfo hints, *res0, *res;
char portbuf[10];
char *h, *cp;
int proxied = 0;
char buffer[1024];
char *proxy_user = NULL, *proxy_pass = NULL;
/* if we have a RSYNC_PROXY env variable then redirect our
* connetcion via a web proxy at the given address. */
h = getenv("RSYNC_PROXY");
proxied = h != NULL && *h != '\0';
if (proxied) {
strlcpy(buffer, h, sizeof buffer);
/* Is the USER:PASS@ prefix present? */
if ((cp = strrchr(buffer, '@')) != NULL) {
*cp++ = '\0';
/* The remainder is the HOST:PORT part. */
h = cp;
if ((cp = strchr(buffer, ':')) == NULL) {
rprintf(FERROR,
"invalid proxy specification: should be USER:PASS@HOST:PORT\n");
return -1;
}
*cp++ = '\0';
proxy_user = buffer;
proxy_pass = cp;
} else {
/* The whole buffer is the HOST:PORT part. */
h = buffer;
}
if ((cp = strchr(h, ':')) == NULL) {
rprintf(FERROR,
"invalid proxy specification: should be HOST:PORT\n");
return -1;
}
*cp++ = '\0';
strlcpy(portbuf, cp, sizeof portbuf);
if (DEBUG_GTE(CONNECT, 1)) {
rprintf(FINFO, "connection via http proxy %s port %s\n",
h, portbuf);
}
} else {
snprintf(portbuf, sizeof portbuf, "%d", port);
h = host;
}
memset(&hints, 0, sizeof hints);
hints.ai_family = af_hint;
hints.ai_socktype = type;
error = getaddrinfo(h, portbuf, &hints, &res0);
if (error) {
rprintf(FERROR, RSYNC_NAME ": getaddrinfo: %s %s: %s\n",
h, portbuf, gai_strerror(error));
return -1;
}
for (res = res0, addr_cnt = 0; res; res = res->ai_next, addr_cnt++) {}
errnos = new_array0(int, addr_cnt);
if (!errnos)
out_of_memory("open_socket_out");
s = -1;
/* Try to connect to all addresses for this machine until we get
* through. It might e.g. be multi-homed, or have both IPv4 and IPv6
* addresses. We need to create a socket for each record, since the
* address record tells us what protocol to use to try to connect. */
for (res = res0, j = 0; res; res = res->ai_next, j++) {
s = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
if (s < 0)
continue;
if (bind_addr
&& try_bind_local(s, res->ai_family, type,
bind_addr) == -1) {
close(s);
s = -1;
continue;
}
if (connect_timeout > 0) {
SIGACTION(SIGALRM, contimeout_handler);
alarm(connect_timeout);
}
set_socket_options(s, sockopts);
while (connect(s, res->ai_addr, res->ai_addrlen) < 0) {
if (connect_timeout < 0)
exit_cleanup(RERR_CONTIMEOUT);
if (errno == EINTR)
continue;
close(s);
s = -1;
break;
}
if (connect_timeout > 0)
alarm(0);
if (s < 0) {
errnos[j] = errno;
continue;
}
if (proxied
&& establish_proxy_connection(s, host, port,
proxy_user, proxy_pass) != 0) {
close(s);
s = -1;
continue;
}
if (DEBUG_GTE(CONNECT, 2)) {
char buf[2048];
if ((error = getnameinfo(res->ai_addr, res->ai_addrlen, buf, sizeof buf, NULL, 0, NI_NUMERICHOST)) != 0)
snprintf(buf, sizeof buf, "*getnameinfo failure: %s*", gai_strerror(error));
rprintf(FINFO, "Connected to %s (%s)\n", h, buf);
}
break;
}
if (s < 0 || DEBUG_GTE(CONNECT, 2)) {
char buf[2048];
for (res = res0, j = 0; res; res = res->ai_next, j++) {
if (errnos[j] == 0)
continue;
if ((error = getnameinfo(res->ai_addr, res->ai_addrlen, buf, sizeof buf, NULL, 0, NI_NUMERICHOST)) != 0)
snprintf(buf, sizeof buf, "*getnameinfo failure: %s*", gai_strerror(error));
rsyserr(FERROR, errnos[j], "failed to connect to %s (%s)", h, buf);
}
if (s < 0)
s = -1;
}
freeaddrinfo(res0);
free(errnos);
return s;
}
/* Open an outgoing socket, but allow for it to be intercepted by
* $RSYNC_CONNECT_PROG, which will execute a program across a TCP
* socketpair rather than really opening a socket.
*
* We use this primarily in testing to detect TCP flow bugs, but not
* cause security problems by really opening remote connections.
*
* This is based on the Samba LIBSMB_PROG feature.
*
* bind_addr: local address to use. Normally NULL to get the stack default. */
int open_socket_out_wrapped(char *host, int port, const char *bind_addr,
int af_hint)
{
char *prog = getenv("RSYNC_CONNECT_PROG");
if (prog && strchr(prog, '%')) {
int hlen = strlen(host);
int len = strlen(prog) + 1;
char *f, *t;
for (f = prog; *f; f++) {
if (*f != '%')
continue;
/* Compute more than enough room. */
if (f[1] == '%')
f++;
else
len += hlen;
}
f = prog;
if (!(prog = new_array(char, len)))
out_of_memory("open_socket_out_wrapped");
for (t = prog; *f; f++) {
if (*f == '%') {
switch (*++f) {
case '%':
/* Just skips the extra '%'. */
break;
case 'H':
memcpy(t, host, hlen);
t += hlen;
continue;
default:
f--; /* pass % through */
break;
}
}
*t++ = *f;
}
*t = '\0';
}
if (DEBUG_GTE(CONNECT, 1)) {
rprintf(FINFO, "%sopening tcp connection to %s port %d\n",
prog ? "Using RSYNC_CONNECT_PROG instead of " : "",
host, port);
}
if (prog)
return sock_exec(prog);
return open_socket_out(host, port, bind_addr, af_hint);
}
/* Open one or more sockets for incoming data using the specified type,
* port, and address.
*
* The getaddrinfo() call may return several address results, e.g. for
* the machine's IPv4 and IPv6 name.
*
* We return an array of file-descriptors to the sockets, with a trailing
* -1 value to indicate the end of the list.
*
* bind_addr: local address to bind, or NULL to allow it to default. */
static int *open_socket_in(int type, int port, const char *bind_addr,
int af_hint)
{
int one = 1;
int s, *socks, maxs, i, ecnt;
struct addrinfo hints, *all_ai, *resp;
char portbuf[10], **errmsgs;
int error;
memset(&hints, 0, sizeof hints);
hints.ai_family = af_hint;
hints.ai_socktype = type;
hints.ai_flags = AI_PASSIVE;
snprintf(portbuf, sizeof portbuf, "%d", port);
error = getaddrinfo(bind_addr, portbuf, &hints, &all_ai);
if (error) {
rprintf(FERROR, RSYNC_NAME ": getaddrinfo: bind address %s: %s\n",
bind_addr, gai_strerror(error));
return NULL;
}
/* Count max number of sockets we might open. */
for (maxs = 0, resp = all_ai; resp; resp = resp->ai_next, maxs++) {}
socks = new_array(int, maxs + 1);
errmsgs = new_array(char *, maxs);
if (!socks || !errmsgs)
out_of_memory("open_socket_in");
/* We may not be able to create the socket, if for example the
* machine knows about IPv6 in the C library, but not in the
* kernel. */
for (resp = all_ai, i = ecnt = 0; resp; resp = resp->ai_next) {
s = socket(resp->ai_family, resp->ai_socktype,
resp->ai_protocol);
if (s == -1) {
int r = asprintf(&errmsgs[ecnt++],
"socket(%d,%d,%d) failed: %s\n",
(int)resp->ai_family, (int)resp->ai_socktype,
(int)resp->ai_protocol, strerror(errno));
if (r < 0)
out_of_memory("open_socket_in");
/* See if there's another address that will work... */
continue;
}
setsockopt(s, SOL_SOCKET, SO_REUSEADDR,
(char *)&one, sizeof one);
if (sockopts)
set_socket_options(s, sockopts);
else
set_socket_options(s, lp_socket_options());
#ifdef IPV6_V6ONLY
if (resp->ai_family == AF_INET6) {
if (setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY,
(char *)&one, sizeof one) < 0
&& default_af_hint != AF_INET6) {
close(s);
continue;
}
}
#endif
/* Now we've got a socket - we need to bind it. */
if (bind(s, resp->ai_addr, resp->ai_addrlen) < 0) {
/* Nope, try another */
int r = asprintf(&errmsgs[ecnt++],
"bind() failed: %s (address-family %d)\n",
strerror(errno), (int)resp->ai_family);
if (r < 0)
out_of_memory("open_socket_in");
close(s);
continue;
}
socks[i++] = s;
}
socks[i] = -1;
if (all_ai)
freeaddrinfo(all_ai);
/* Only output the socket()/bind() messages if we were totally
* unsuccessful, or if the daemon is being run with -vv. */
for (s = 0; s < ecnt; s++) {
if (!i || DEBUG_GTE(BIND, 1))
rwrite(FLOG, errmsgs[s], strlen(errmsgs[s]), 0);
free(errmsgs[s]);
}
free(errmsgs);
if (!i) {
rprintf(FERROR,
"unable to bind any inbound sockets on port %d\n",
port);
free(socks);
return NULL;
}
return socks;
}
/* Determine if a file descriptor is in fact a socket. */
int is_a_socket(int fd)
{
int v;
socklen_t l = sizeof (int);
/* Parameters to getsockopt, setsockopt etc are very
* unstandardized across platforms, so don't be surprised if
* there are compiler warnings on e.g. SCO OpenSwerver or AIX.
* It seems they all eventually get the right idea.
*
* Debian says: ``The fifth argument of getsockopt and
* setsockopt is in reality an int [*] (and this is what BSD
* 4.* and libc4 and libc5 have). Some POSIX confusion
* resulted in the present socklen_t. The draft standard has
* not been adopted yet, but glibc2 already follows it and
* also has socklen_t [*]. See also accept(2).''
*
* We now return to your regularly scheduled programming. */
return getsockopt(fd, SOL_SOCKET, SO_TYPE, (char *)&v, &l) == 0;
}
static RETSIGTYPE sigchld_handler(UNUSED(int val))
{
#ifdef WNOHANG
while (waitpid(-1, NULL, WNOHANG) > 0) {}
#endif
#ifndef HAVE_SIGACTION
signal(SIGCHLD, sigchld_handler);
#endif
}
void start_accept_loop(int port, int (*fn)(int, int))
{
fd_set deffds;
int *sp, maxfd, i;
#ifdef HAVE_SIGACTION
sigact.sa_flags = SA_NOCLDSTOP;
#endif
/* open an incoming socket */
sp = open_socket_in(SOCK_STREAM, port, bind_address, default_af_hint);
if (sp == NULL)
exit_cleanup(RERR_SOCKETIO);
/* ready to listen */
FD_ZERO(&deffds);
for (i = 0, maxfd = -1; sp[i] >= 0; i++) {
if (listen(sp[i], lp_listen_backlog()) < 0) {
rsyserr(FERROR, errno, "listen() on socket failed");
#ifdef INET6
if (errno == EADDRINUSE && i > 0) {
rprintf(FINFO,
"Try using --ipv4 or --ipv6 to avoid this listen() error.\n");
}
#endif
exit_cleanup(RERR_SOCKETIO);
}
FD_SET(sp[i], &deffds);
if (maxfd < sp[i])
maxfd = sp[i];
}
/* now accept incoming connections - forking a new process
* for each incoming connection */
while (1) {
fd_set fds;
pid_t pid;
int fd;
struct sockaddr_storage addr;
socklen_t addrlen = sizeof addr;
/* close log file before the potentially very long select so
* file can be trimmed by another process instead of growing
* forever */
logfile_close();
#ifdef FD_COPY
FD_COPY(&deffds, &fds);
#else
fds = deffds;
#endif
if (select(maxfd + 1, &fds, NULL, NULL, NULL) < 1)
continue;
for (i = 0, fd = -1; sp[i] >= 0; i++) {
if (FD_ISSET(sp[i], &fds)) {
fd = accept(sp[i], (struct sockaddr *)&addr,
&addrlen);
break;
}
}
if (fd < 0)
continue;
SIGACTION(SIGCHLD, sigchld_handler);
if ((pid = fork()) == 0) {
int ret;
for (i = 0; sp[i] >= 0; i++)
close(sp[i]);
/* Re-open log file in child before possibly giving
* up privileges (see logfile_close() above). */
logfile_reopen();
ret = fn(fd, fd);
close_all();
_exit(ret);
} else if (pid < 0) {
rsyserr(FERROR, errno,
"could not create child server process");
close(fd);
/* This might have happened because we're
* overloaded. Sleep briefly before trying to
* accept again. */
sleep(2);
} else {
/* Parent doesn't need this fd anymore. */
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},
#ifdef SO_BROADCAST
{"SO_BROADCAST", SOL_SOCKET, SO_BROADCAST, 0, OPT_BOOL},
#endif
#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) {
rsyserr(FERROR, errno,
"failed to set socket option %s", tok);
}
}
free(options);
}
/* This is like socketpair but uses tcp. The function guarantees that nobody
* else can attach to the socket, or if they do that this function fails and
* the socket gets closed. Returns 0 on success, -1 on failure. The resulting
* file descriptors are symmetrical. Currently only for RSYNC_CONNECT_PROG. */
static int socketpair_tcp(int fd[2])
{
int listener;
struct sockaddr_in sock;
struct sockaddr_in sock2;
socklen_t socklen = sizeof sock;
int connect_done = 0;
fd[0] = fd[1] = listener = -1;
memset(&sock, 0, sizeof sock);
if ((listener = socket(PF_INET, SOCK_STREAM, 0)) == -1)
goto failed;
memset(&sock2, 0, sizeof sock2);
#ifdef HAVE_SOCKADDR_IN_LEN
sock2.sin_len = sizeof sock2;
#endif
sock2.sin_family = PF_INET;
sock2.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
if (bind(listener, (struct sockaddr *)&sock2, sizeof sock2) != 0
|| listen(listener, 1) != 0
|| getsockname(listener, (struct sockaddr *)&sock, &socklen) != 0
|| (fd[1] = socket(PF_INET, SOCK_STREAM, 0)) == -1)
goto failed;
set_nonblocking(fd[1]);
sock.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
if (connect(fd[1], (struct sockaddr *)&sock, sizeof sock) == -1) {
if (errno != EINPROGRESS)
goto failed;
} else
connect_done = 1;
if ((fd[0] = accept(listener, (struct sockaddr *)&sock2, &socklen)) == -1)
goto failed;
close(listener);
listener = -1;
set_blocking(fd[1]);
if (connect_done == 0) {
if (connect(fd[1], (struct sockaddr *)&sock, sizeof sock) != 0
&& errno != EISCONN)
goto failed;
}
/* all OK! */
return 0;
failed:
if (fd[0] != -1)
close(fd[0]);
if (fd[1] != -1)
close(fd[1]);
if (listener != -1)
close(listener);
return -1;
}
/* Run a program on a local tcp socket, so that we can talk to it's stdin and
* stdout. This is used to fake a connection to a daemon for testing -- not
* for the normal case of running SSH.
*
* Retruns a socket which is attached to a subprocess running "prog". stdin and
* stdout are attached. stderr is left attached to the original stderr. */
static int sock_exec(const char *prog)
{
pid_t pid;
int fd[2];
if (socketpair_tcp(fd) != 0) {
rsyserr(FERROR, errno, "socketpair_tcp failed");
return -1;
}
if (DEBUG_GTE(CMD, 1))
rprintf(FINFO, "Running socket program: \"%s\"\n", prog);
pid = fork();
if (pid < 0) {
rsyserr(FERROR, errno, "fork");
exit_cleanup(RERR_IPC);
}
if (pid == 0) {
close(fd[0]);
if (dup2(fd[1], STDIN_FILENO) < 0
|| dup2(fd[1], STDOUT_FILENO) < 0) {
fprintf(stderr, "Failed to run \"%s\"\n", prog);
exit(1);
}
exit(system(prog));
}
close(fd[1]);
return fd[0];
}