src/sock.c - haproxy - Gitiles

 /*
  * Generic code for native (BSD-compatible) sockets
  *
  * Copyright 2000-2020 Willy Tarreau <w@1wt.eu>
  *
  * 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.
  *
  */

 #include <ctype.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <time.h>

 #include <sys/param.h>
 #include <sys/socket.h>
 #include <sys/types.h>

 #include <net/if.h>

 #include <haproxy/api.h>
 #include <haproxy/connection.h>
 #include <haproxy/listener-t.h>
 #include <haproxy/namespace.h>
 #include <haproxy/sock.h>
 #include <haproxy/sock_inet.h>
 #include <haproxy/tools.h>

 /* the list of remaining sockets transferred from an older process */
 struct xfer_sock_list *xfer_sock_list = NULL;

 /* Create a socket to connect to the server in conn->dst (which MUST be valid),
  * using the configured namespace if needed, or the one passed by the proxy
  * protocol if required to do so. It ultimately calls socket() or socketat()
  * and returns the FD or error code.
  */
 int sock_create_server_socket(struct connection *conn)
 {
 	const struct netns_entry *ns = NULL;

 #ifdef USE_NS
 	if (objt_server(conn->target)) {
 		if (__objt_server(conn->target)->flags & SRV_F_USE_NS_FROM_PP)
 			ns = conn->proxy_netns;
 		else
 			ns = __objt_server(conn->target)->netns;
 	}
 #endif
 	return my_socketat(ns, conn->dst->ss_family, SOCK_STREAM, 0);
 }

 /*
  * Retrieves the source address for the socket <fd>, with <dir> indicating
  * if we're a listener (=0) or an initiator (!=0). It returns 0 in case of
  * success, -1 in case of error. The socket's source address is stored in
  * <sa> for <salen> bytes.
  */
 int sock_get_src(int fd, struct sockaddr *sa, socklen_t salen, int dir)
 {
 	if (dir)
 		return getsockname(fd, sa, &salen);
 	else
 		return getpeername(fd, sa, &salen);
 }

 /*
  * Retrieves the original destination address for the socket <fd>, with <dir>
  * indicating if we're a listener (=0) or an initiator (!=0). It returns 0 in
  * case of success, -1 in case of error. The socket's source address is stored
  * in <sa> for <salen> bytes.
  */
 int sock_get_dst(int fd, struct sockaddr *sa, socklen_t salen, int dir)
 {
 	if (dir)
 		return getpeername(fd, sa, &salen);
 	else
 		return getsockname(fd, sa, &salen);
 }

 /* Try to retrieve exported sockets from worker at CLI <unixsocket>. These
  * ones will be placed into the xfer_sock_list for later use by function
  * sock_find_compatible_fd(). Returns 0 on success, -1 on failure.
  */
 int sock_get_old_sockets(const char *unixsocket)
 {
 	char *cmsgbuf = NULL, *tmpbuf = NULL;
 	int *tmpfd = NULL;
 	struct sockaddr_un addr;
 	struct cmsghdr *cmsg;
 	struct msghdr msghdr;
 	struct iovec iov;
 	struct xfer_sock_list *xfer_sock = NULL;
 	struct timeval tv = { .tv_sec = 1, .tv_usec = 0 };
 	int sock = -1;
 	int ret = -1;
 	int ret2 = -1;
 	int fd_nb;
 	int got_fd = 0;
 	int cur_fd = 0;
 	size_t maxoff = 0, curoff = 0;

 	memset(&msghdr, 0, sizeof(msghdr));
 	cmsgbuf = malloc(CMSG_SPACE(sizeof(int)) * MAX_SEND_FD);
 	if (!cmsgbuf) {
 		ha_warning("Failed to allocate memory to send sockets\n");
 		goto out;
 	}

 	sock = socket(PF_UNIX, SOCK_STREAM, 0);
 	if (sock < 0) {
 		ha_warning("Failed to connect to the old process socket '%s'\n", unixsocket);
 		goto out;
 	}

 	strncpy(addr.sun_path, unixsocket, sizeof(addr.sun_path) - 1);
 	addr.sun_path[sizeof(addr.sun_path) - 1] = 0;
 	addr.sun_family = PF_UNIX;

 	ret = connect(sock, (struct sockaddr *)&addr, sizeof(addr));
 	if (ret < 0) {
 		ha_warning("Failed to connect to the old process socket '%s'\n", unixsocket);
 		goto out;
 	}

 	setsockopt(sock, SOL_SOCKET, SO_RCVTIMEO, (void *)&tv, sizeof(tv));
 	iov.iov_base = &fd_nb;
 	iov.iov_len = sizeof(fd_nb);
 	msghdr.msg_iov = &iov;
 	msghdr.msg_iovlen = 1;

 	if (send(sock, "_getsocks\n", strlen("_getsocks\n"), 0) != strlen("_getsocks\n")) {
 		ha_warning("Failed to get the number of sockets to be transferred !\n");
 		goto out;
 	}

 	/* First, get the number of file descriptors to be received */
 	if (recvmsg(sock, &msghdr, MSG_WAITALL) != sizeof(fd_nb)) {
 		ha_warning("Failed to get the number of sockets to be transferred !\n");
 		goto out;
 	}

 	if (fd_nb == 0) {
 		ret2 = 0;
 		goto out;
 	}

 	tmpbuf = malloc(fd_nb * (1 + MAXPATHLEN + 1 + IFNAMSIZ + sizeof(int)));
 	if (tmpbuf == NULL) {
 		ha_warning("Failed to allocate memory while receiving sockets\n");
 		goto out;
 	}

 	tmpfd = malloc(fd_nb * sizeof(int));
 	if (tmpfd == NULL) {
 		ha_warning("Failed to allocate memory while receiving sockets\n");
 		goto out;
 	}

 	msghdr.msg_control = cmsgbuf;
 	msghdr.msg_controllen = CMSG_SPACE(sizeof(int)) * MAX_SEND_FD;
 	iov.iov_len = MAX_SEND_FD * (1 + MAXPATHLEN + 1 + IFNAMSIZ + sizeof(int));

 	do {
 		int ret3;

 		iov.iov_base = tmpbuf + curoff;

 		ret = recvmsg(sock, &msghdr, 0);

 		if (ret == -1 && errno == EINTR)
 			continue;

 		if (ret <= 0)
 			break;

 		/* Send an ack to let the sender know we got the sockets
 		 * and it can send some more
 		 */
 		do {
 			ret3 = send(sock, &got_fd, sizeof(got_fd), 0);
 		} while (ret3 == -1 && errno == EINTR);

 		for (cmsg = CMSG_FIRSTHDR(&msghdr); cmsg != NULL; cmsg = CMSG_NXTHDR(&msghdr, cmsg)) {
 			if (cmsg->cmsg_level == SOL_SOCKET && cmsg->cmsg_type == SCM_RIGHTS) {
 				size_t totlen = cmsg->cmsg_len - CMSG_LEN(0);

 				if (totlen / sizeof(int) + got_fd > fd_nb) {
 					ha_warning("Got to many sockets !\n");
 					goto out;
 				}

 				/*
 				 * Be paranoid and use memcpy() to avoid any
 				 * potential alignment issue.
 				 */
 				memcpy(&tmpfd[got_fd], CMSG_DATA(cmsg), totlen);
 				got_fd += totlen / sizeof(int);
 			}
 		}
 		curoff += ret;
 	} while (got_fd < fd_nb);

 	if (got_fd != fd_nb) {
 		ha_warning("We didn't get the expected number of sockets (expecting %d got %d)\n",
 			   fd_nb, got_fd);
 		goto out;
 	}

 	maxoff = curoff;
 	curoff = 0;

 	for (cur_fd = 0; cur_fd < got_fd; cur_fd++) {
 		int fd = tmpfd[cur_fd];
 		socklen_t socklen;
 		int val;
 		int len;

 		xfer_sock = calloc(1, sizeof(*xfer_sock));
 		if (!xfer_sock) {
 			ha_warning("Failed to allocate memory in get_old_sockets() !\n");
 			break;
 		}
 		xfer_sock->fd = -1;

 		socklen = sizeof(xfer_sock->addr);
 		if (getsockname(fd, (struct sockaddr *)&xfer_sock->addr, &socklen) != 0) {
 			ha_warning("Failed to get socket address\n");
 			free(xfer_sock);
 			xfer_sock = NULL;
 			continue;
 		}

 		if (curoff >= maxoff) {
 			ha_warning("Inconsistency while transferring sockets\n");
 			goto out;
 		}

 		len = tmpbuf[curoff++];
 		if (len > 0) {
 			/* We have a namespace */
 			if (curoff + len > maxoff) {
 				ha_warning("Inconsistency while transferring sockets\n");
 				goto out;
 			}
 			xfer_sock->namespace = malloc(len + 1);
 			if (!xfer_sock->namespace) {
 				ha_warning("Failed to allocate memory while transferring sockets\n");
 				goto out;
 			}
 			memcpy(xfer_sock->namespace, &tmpbuf[curoff], len);
 			xfer_sock->namespace[len] = 0;
 			xfer_sock->ns_namelen = len;
 			curoff += len;
 		}

 		if (curoff >= maxoff) {
 			ha_warning("Inconsistency while transferring sockets\n");
 			goto out;
 		}

 		len = tmpbuf[curoff++];
 		if (len > 0) {
 			/* We have an interface */
 			if (curoff + len > maxoff) {
 				ha_warning("Inconsistency while transferring sockets\n");
 				goto out;
 			}
 			xfer_sock->iface = malloc(len + 1);
 			if (!xfer_sock->iface) {
 				ha_warning("Failed to allocate memory while transferring sockets\n");
 				goto out;
 			}
 			memcpy(xfer_sock->iface, &tmpbuf[curoff], len);
 			xfer_sock->iface[len] = 0;
 			xfer_sock->if_namelen = len;
 			curoff += len;
 		}

 		if (curoff + sizeof(int) > maxoff) {
 			ha_warning("Inconsistency while transferring sockets\n");
 			goto out;
 		}

 		/* we used to have 32 bits of listener options here but we don't
 		 * use them anymore.
 		 */
 		curoff += sizeof(int);

 		/* determine the foreign status directly from the socket itself */
 		if (sock_inet_is_foreign(fd, xfer_sock->addr.ss_family))
 			xfer_sock->options |= SOCK_XFER_OPT_FOREIGN;

 		socklen = sizeof(val);
 		if (getsockopt(fd, SOL_SOCKET, SO_TYPE, &val, &socklen) == 0 && val == SOCK_DGRAM)
 			xfer_sock->options |= SOCK_XFER_OPT_DGRAM;

 #if defined(IPV6_V6ONLY)
 		/* keep only the v6only flag depending on what's currently
 		 * active on the socket, and always drop the v4v6 one.
 		 */
 		socklen = sizeof(val);
 		if (xfer_sock->addr.ss_family == AF_INET6 &&
 		    getsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &val, &socklen) == 0 && val > 0)
 			xfer_sock->options |= SOCK_XFER_OPT_V6ONLY;
 #endif

 		xfer_sock->fd = fd;
 		if (xfer_sock_list)
 			xfer_sock_list->prev = xfer_sock;
 		xfer_sock->next = xfer_sock_list;
 		xfer_sock->prev = NULL;
 		xfer_sock_list = xfer_sock;
 		xfer_sock = NULL;
 	}

 	ret2 = 0;
 out:
 	/* If we failed midway make sure to close the remaining
 	 * file descriptors
 	 */
 	if (tmpfd != NULL && cur_fd < got_fd) {
 		for (; cur_fd < got_fd; cur_fd++) {
 			close(tmpfd[cur_fd]);
 		}
 	}

 	free(tmpbuf);
 	free(tmpfd);
 	free(cmsgbuf);

 	if (sock != -1)
 		close(sock);

 	if (xfer_sock) {
 		free(xfer_sock->namespace);
 		free(xfer_sock->iface);
 		if (xfer_sock->fd != -1)
 			close(xfer_sock->fd);
 		free(xfer_sock);
 	}
 	return (ret2);
 }

 /* When binding the receivers, check if a socket has been sent to us by the
  * previous process that we could reuse, instead of creating a new one. Note
  * that some address family-specific options are checked on the listener and
  * on the socket. Typically for AF_INET and AF_INET6, we check for transparent
  * mode, and for AF_INET6 we also check for "v4v6" or "v6only". The reused
  * socket is automatically removed from the list so that it's not proposed
  * anymore.
  */
 int sock_find_compatible_fd(const struct receiver *rx)
 {
 	struct xfer_sock_list *xfer_sock = xfer_sock_list;
 	int options = 0;
 	int if_namelen = 0;
 	int ns_namelen = 0;
 	int ret = -1;

 	if (!rx->proto->fam->addrcmp)
 		return -1;

 	if (rx->proto->sock_type == SOCK_DGRAM)
 		options |= SOCK_XFER_OPT_DGRAM;

 	if (rx->settings->options & RX_O_FOREIGN)
 		options |= SOCK_XFER_OPT_FOREIGN;

 	if (rx->addr.ss_family == AF_INET6) {
 		/* Prepare to match the v6only option against what we really want. Note
 		 * that sadly the two options are not exclusive to each other and that
 		 * v6only is stronger than v4v6.
 		 */
 		if ((rx->settings->options & RX_O_V6ONLY) ||
 		    (sock_inet6_v6only_default && !(rx->settings->options & RX_O_V4V6)))
 			options |= SOCK_XFER_OPT_V6ONLY;
 	}

 	if (rx->settings->interface)
 		if_namelen = strlen(rx->settings->interface);
 #ifdef USE_NS
 	if (rx->settings->netns)
 		ns_namelen = rx->settings->netns->name_len;
 #endif

 	while (xfer_sock) {
 		if ((options == xfer_sock->options) &&
 		    (if_namelen == xfer_sock->if_namelen) &&
 		    (ns_namelen == xfer_sock->ns_namelen) &&
 		    (!if_namelen || strcmp(rx->settings->interface, xfer_sock->iface) == 0) &&
 #ifdef USE_NS
 		    (!ns_namelen || strcmp(rx->settings->netns->node.key, xfer_sock->namespace) == 0) &&
 #endif
 		    rx->proto->fam->addrcmp(&xfer_sock->addr, &rx->addr) == 0)
 			break;
 		xfer_sock = xfer_sock->next;
 	}

 	if (xfer_sock != NULL) {
 		ret = xfer_sock->fd;
 		if (xfer_sock == xfer_sock_list)
 			xfer_sock_list = xfer_sock->next;
 		if (xfer_sock->prev)
 			xfer_sock->prev->next = xfer_sock->next;
 		if (xfer_sock->next)
 			xfer_sock->next->prev = xfer_sock->prev;
 		free(xfer_sock->iface);
 		free(xfer_sock->namespace);
 		free(xfer_sock);
 	}
 	return ret;
 }

 /*
  * Local variables:
  *  c-indent-level: 8
  *  c-basic-offset: 8
  * End:
  */
	/*
	* Generic code for native (BSD-compatible) sockets
	*
	* Copyright 2000-2020 Willy Tarreau <w@1wt.eu>
	*
	* 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.
	*
	*/

	#include <ctype.h>
	#include <errno.h>
	#include <fcntl.h>
	#include <stdio.h>
	#include <stdlib.h>
	#include <string.h>
	#include <time.h>

	#include <sys/param.h>
	#include <sys/socket.h>
	#include <sys/types.h>

	#include <net/if.h>

	#include <haproxy/api.h>
	#include <haproxy/connection.h>
	#include <haproxy/listener-t.h>
	#include <haproxy/namespace.h>
	#include <haproxy/sock.h>
	#include <haproxy/sock_inet.h>
	#include <haproxy/tools.h>

	/* the list of remaining sockets transferred from an older process */
	struct xfer_sock_list *xfer_sock_list = NULL;

	/* Create a socket to connect to the server in conn->dst (which MUST be valid),
	* using the configured namespace if needed, or the one passed by the proxy
	* protocol if required to do so. It ultimately calls socket() or socketat()
	* and returns the FD or error code.
	*/
	int sock_create_server_socket(struct connection *conn)
	{
	const struct netns_entry *ns = NULL;

	#ifdef USE_NS
	if (objt_server(conn->target)) {
	if (__objt_server(conn->target)->flags & SRV_F_USE_NS_FROM_PP)
	ns = conn->proxy_netns;
	else
	ns = __objt_server(conn->target)->netns;
	}
	#endif
	return my_socketat(ns, conn->dst->ss_family, SOCK_STREAM, 0);
	}

	/*
	* Retrieves the source address for the socket <fd>, with <dir> indicating
	* if we're a listener (=0) or an initiator (!=0). It returns 0 in case of
	* success, -1 in case of error. The socket's source address is stored in
	* <sa> for <salen> bytes.
	*/
	int sock_get_src(int fd, struct sockaddr *sa, socklen_t salen, int dir)
	{
	if (dir)
	return getsockname(fd, sa, &salen);
	else
	return getpeername(fd, sa, &salen);
	}

	/*
	* Retrieves the original destination address for the socket <fd>, with <dir>
	* indicating if we're a listener (=0) or an initiator (!=0). It returns 0 in
	* case of success, -1 in case of error. The socket's source address is stored
	* in <sa> for <salen> bytes.
	*/
	int sock_get_dst(int fd, struct sockaddr *sa, socklen_t salen, int dir)
	{
	if (dir)
	return getpeername(fd, sa, &salen);
	else
	return getsockname(fd, sa, &salen);
	}

	/* Try to retrieve exported sockets from worker at CLI <unixsocket>. These
	* ones will be placed into the xfer_sock_list for later use by function
	* sock_find_compatible_fd(). Returns 0 on success, -1 on failure.
	*/
	int sock_get_old_sockets(const char *unixsocket)
	{
	char cmsgbuf = NULL, tmpbuf = NULL;
	int *tmpfd = NULL;
	struct sockaddr_un addr;
	struct cmsghdr *cmsg;
	struct msghdr msghdr;
	struct iovec iov;
	struct xfer_sock_list *xfer_sock = NULL;
	struct timeval tv = { .tv_sec = 1, .tv_usec = 0 };
	int sock = -1;
	int ret = -1;
	int ret2 = -1;
	int fd_nb;
	int got_fd = 0;
	int cur_fd = 0;
	size_t maxoff = 0, curoff = 0;

	memset(&msghdr, 0, sizeof(msghdr));
	cmsgbuf = malloc(CMSG_SPACE(sizeof(int)) * MAX_SEND_FD);
	if (!cmsgbuf) {
	ha_warning("Failed to allocate memory to send sockets\n");
	goto out;
	}

	sock = socket(PF_UNIX, SOCK_STREAM, 0);
	if (sock < 0) {
	ha_warning("Failed to connect to the old process socket '%s'\n", unixsocket);
	goto out;
	}

	strncpy(addr.sun_path, unixsocket, sizeof(addr.sun_path) - 1);
	addr.sun_path[sizeof(addr.sun_path) - 1] = 0;
	addr.sun_family = PF_UNIX;

	ret = connect(sock, (struct sockaddr *)&addr, sizeof(addr));
	if (ret < 0) {
	ha_warning("Failed to connect to the old process socket '%s'\n", unixsocket);
	goto out;
	}

	setsockopt(sock, SOL_SOCKET, SO_RCVTIMEO, (void *)&tv, sizeof(tv));
	iov.iov_base = &fd_nb;
	iov.iov_len = sizeof(fd_nb);
	msghdr.msg_iov = &iov;
	msghdr.msg_iovlen = 1;

	if (send(sock, "_getsocks\n", strlen("_getsocks\n"), 0) != strlen("_getsocks\n")) {
	ha_warning("Failed to get the number of sockets to be transferred !\n");
	goto out;
	}

	/* First, get the number of file descriptors to be received */
	if (recvmsg(sock, &msghdr, MSG_WAITALL) != sizeof(fd_nb)) {
	ha_warning("Failed to get the number of sockets to be transferred !\n");
	goto out;
	}

	if (fd_nb == 0) {
	ret2 = 0;
	goto out;
	}

	tmpbuf = malloc(fd_nb * (1 + MAXPATHLEN + 1 + IFNAMSIZ + sizeof(int)));
	if (tmpbuf == NULL) {
	ha_warning("Failed to allocate memory while receiving sockets\n");
	goto out;
	}

	tmpfd = malloc(fd_nb * sizeof(int));
	if (tmpfd == NULL) {
	ha_warning("Failed to allocate memory while receiving sockets\n");
	goto out;
	}

	msghdr.msg_control = cmsgbuf;
	msghdr.msg_controllen = CMSG_SPACE(sizeof(int)) * MAX_SEND_FD;
	iov.iov_len = MAX_SEND_FD * (1 + MAXPATHLEN + 1 + IFNAMSIZ + sizeof(int));

	do {
	int ret3;

	iov.iov_base = tmpbuf + curoff;

	ret = recvmsg(sock, &msghdr, 0);

	if (ret == -1 && errno == EINTR)
	continue;

	if (ret <= 0)
	break;

	/* Send an ack to let the sender know we got the sockets
	* and it can send some more
	*/
	do {
	ret3 = send(sock, &got_fd, sizeof(got_fd), 0);
	} while (ret3 == -1 && errno == EINTR);

	for (cmsg = CMSG_FIRSTHDR(&msghdr); cmsg != NULL; cmsg = CMSG_NXTHDR(&msghdr, cmsg)) {
	if (cmsg->cmsg_level == SOL_SOCKET && cmsg->cmsg_type == SCM_RIGHTS) {
	size_t totlen = cmsg->cmsg_len - CMSG_LEN(0);

	if (totlen / sizeof(int) + got_fd > fd_nb) {
	ha_warning("Got to many sockets !\n");
	goto out;
	}

	/*
	* Be paranoid and use memcpy() to avoid any
	* potential alignment issue.
	*/
	memcpy(&tmpfd[got_fd], CMSG_DATA(cmsg), totlen);
	got_fd += totlen / sizeof(int);
	}
	}
	curoff += ret;
	} while (got_fd < fd_nb);

	if (got_fd != fd_nb) {
	ha_warning("We didn't get the expected number of sockets (expecting %d got %d)\n",
	fd_nb, got_fd);
	goto out;
	}

	maxoff = curoff;
	curoff = 0;

	for (cur_fd = 0; cur_fd < got_fd; cur_fd++) {
	int fd = tmpfd[cur_fd];
	socklen_t socklen;
	int val;
	int len;

	xfer_sock = calloc(1, sizeof(*xfer_sock));
	if (!xfer_sock) {
	ha_warning("Failed to allocate memory in get_old_sockets() !\n");
	break;
	}
	xfer_sock->fd = -1;

	socklen = sizeof(xfer_sock->addr);
	if (getsockname(fd, (struct sockaddr *)&xfer_sock->addr, &socklen) != 0) {
	ha_warning("Failed to get socket address\n");
	free(xfer_sock);
	xfer_sock = NULL;
	continue;
	}

	if (curoff >= maxoff) {
	ha_warning("Inconsistency while transferring sockets\n");
	goto out;
	}

	len = tmpbuf[curoff++];
	if (len > 0) {
	/* We have a namespace */
	if (curoff + len > maxoff) {
	ha_warning("Inconsistency while transferring sockets\n");
	goto out;
	}
	xfer_sock->namespace = malloc(len + 1);
	if (!xfer_sock->namespace) {
	ha_warning("Failed to allocate memory while transferring sockets\n");
	goto out;
	}
	memcpy(xfer_sock->namespace, &tmpbuf[curoff], len);
	xfer_sock->namespace[len] = 0;
	xfer_sock->ns_namelen = len;
	curoff += len;
	}

	if (curoff >= maxoff) {
	ha_warning("Inconsistency while transferring sockets\n");
	goto out;
	}

	len = tmpbuf[curoff++];
	if (len > 0) {
	/* We have an interface */
	if (curoff + len > maxoff) {
	ha_warning("Inconsistency while transferring sockets\n");
	goto out;
	}
	xfer_sock->iface = malloc(len + 1);
	if (!xfer_sock->iface) {
	ha_warning("Failed to allocate memory while transferring sockets\n");
	goto out;
	}
	memcpy(xfer_sock->iface, &tmpbuf[curoff], len);
	xfer_sock->iface[len] = 0;
	xfer_sock->if_namelen = len;
	curoff += len;
	}

	if (curoff + sizeof(int) > maxoff) {
	ha_warning("Inconsistency while transferring sockets\n");
	goto out;
	}

	/* we used to have 32 bits of listener options here but we don't
	* use them anymore.
	*/
	curoff += sizeof(int);

	/* determine the foreign status directly from the socket itself */
	if (sock_inet_is_foreign(fd, xfer_sock->addr.ss_family))
	xfer_sock->options \|= SOCK_XFER_OPT_FOREIGN;

	socklen = sizeof(val);
	if (getsockopt(fd, SOL_SOCKET, SO_TYPE, &val, &socklen) == 0 && val == SOCK_DGRAM)
	xfer_sock->options \|= SOCK_XFER_OPT_DGRAM;

	#if defined(IPV6_V6ONLY)
	/* keep only the v6only flag depending on what's currently
	* active on the socket, and always drop the v4v6 one.
	*/
	socklen = sizeof(val);
	if (xfer_sock->addr.ss_family == AF_INET6 &&
	getsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &val, &socklen) == 0 && val > 0)
	xfer_sock->options \|= SOCK_XFER_OPT_V6ONLY;
	#endif

	xfer_sock->fd = fd;
	if (xfer_sock_list)
	xfer_sock_list->prev = xfer_sock;
	xfer_sock->next = xfer_sock_list;
	xfer_sock->prev = NULL;
	xfer_sock_list = xfer_sock;
	xfer_sock = NULL;
	}

	ret2 = 0;
	out:
	/* If we failed midway make sure to close the remaining
	* file descriptors
	*/
	if (tmpfd != NULL && cur_fd < got_fd) {
	for (; cur_fd < got_fd; cur_fd++) {
	close(tmpfd[cur_fd]);
	}
	}

	free(tmpbuf);
	free(tmpfd);
	free(cmsgbuf);

	if (sock != -1)
	close(sock);

	if (xfer_sock) {
	free(xfer_sock->namespace);
	free(xfer_sock->iface);
	if (xfer_sock->fd != -1)
	close(xfer_sock->fd);
	free(xfer_sock);
	}
	return (ret2);
	}

	/* When binding the receivers, check if a socket has been sent to us by the
	* previous process that we could reuse, instead of creating a new one. Note
	* that some address family-specific options are checked on the listener and
	* on the socket. Typically for AF_INET and AF_INET6, we check for transparent
	* mode, and for AF_INET6 we also check for "v4v6" or "v6only". The reused
	* socket is automatically removed from the list so that it's not proposed
	* anymore.
	*/
	int sock_find_compatible_fd(const struct receiver *rx)
	{
	struct xfer_sock_list *xfer_sock = xfer_sock_list;
	int options = 0;
	int if_namelen = 0;
	int ns_namelen = 0;
	int ret = -1;

	if (!rx->proto->fam->addrcmp)
	return -1;

	if (rx->proto->sock_type == SOCK_DGRAM)
	options \|= SOCK_XFER_OPT_DGRAM;

	if (rx->settings->options & RX_O_FOREIGN)
	options \|= SOCK_XFER_OPT_FOREIGN;

	if (rx->addr.ss_family == AF_INET6) {
	/* Prepare to match the v6only option against what we really want. Note
	* that sadly the two options are not exclusive to each other and that
	* v6only is stronger than v4v6.
	*/
	if ((rx->settings->options & RX_O_V6ONLY) \|\|
	(sock_inet6_v6only_default && !(rx->settings->options & RX_O_V4V6)))
	options \|= SOCK_XFER_OPT_V6ONLY;
	}

	if (rx->settings->interface)
	if_namelen = strlen(rx->settings->interface);
	#ifdef USE_NS
	if (rx->settings->netns)
	ns_namelen = rx->settings->netns->name_len;
	#endif

	while (xfer_sock) {
	if ((options == xfer_sock->options) &&
	(if_namelen == xfer_sock->if_namelen) &&
	(ns_namelen == xfer_sock->ns_namelen) &&
	(!if_namelen \|\| strcmp(rx->settings->interface, xfer_sock->iface) == 0) &&
	#ifdef USE_NS
	(!ns_namelen \|\| strcmp(rx->settings->netns->node.key, xfer_sock->namespace) == 0) &&
	#endif
	rx->proto->fam->addrcmp(&xfer_sock->addr, &rx->addr) == 0)
	break;
	xfer_sock = xfer_sock->next;
	}

	if (xfer_sock != NULL) {
	ret = xfer_sock->fd;
	if (xfer_sock == xfer_sock_list)
	xfer_sock_list = xfer_sock->next;
	if (xfer_sock->prev)
	xfer_sock->prev->next = xfer_sock->next;
	if (xfer_sock->next)
	xfer_sock->next->prev = xfer_sock->prev;
	free(xfer_sock->iface);
	free(xfer_sock->namespace);
	free(xfer_sock);
	}
	return ret;
	}

	/*
	* Local variables:
	* c-indent-level: 8
	* c-basic-offset: 8
	* End:
	*/