implement file descriptor passing in the imsg/msgbuf framework, and use

it to let the main process to prepare new listening sockets (socket() and
bind()) on behalf of the session engine, which of course cannot bind() to
ports < 1024 any more once it dropped privileges. with some help from theo,
claudio ok

7 files changed, 188 insertions, 68 deletions

diff --git a/usr.sbin/bgpd/bgpd.c b/usr.sbin/bgpd/bgpd.c
index bce647303fc..3cfcafbd986 100644
--- a/usr.sbin/bgpd/bgpd.c
+++ b/usr.sbin/bgpd/bgpd.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: bgpd.c,v 1.95 2004/06/06 17:38:10 henning Exp $ */
+/*	$OpenBSD: bgpd.c,v 1.96 2004/06/20 17:49:46 henning Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -176,22 +176,24 @@ main(int argc, char *argv[])
 
 	log_info("startup");
 
-	if (pipe(pipe_m2s) == -1)
-		fatal("pipe");
+	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pipe_m2s) == -1)
+		fatal("socketpair");
 	if (fcntl(pipe_m2s[0], F_SETFL, O_NONBLOCK) == -1 ||
 	    fcntl(pipe_m2s[1], F_SETFL, O_NONBLOCK) == -1)
 		fatal("fcntl");
-	if (pipe(pipe_m2r) == -1)
-		fatal("pipe");
+	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pipe_m2r) == -1)
+		fatal("socketpair");
 	if (fcntl(pipe_m2r[0], F_SETFL, O_NONBLOCK) == -1 ||
 	    fcntl(pipe_m2r[1], F_SETFL, O_NONBLOCK) == -1)
 		fatal("fcntl");
-	if (pipe(pipe_s2r) == -1)
-		fatal("pipe");
+	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pipe_s2r) == -1)
+		fatal("socketpair");
 	if (fcntl(pipe_s2r[0], F_SETFL, O_NONBLOCK) == -1 ||
 	    fcntl(pipe_s2r[1], F_SETFL, O_NONBLOCK) == -1)
 		fatal("fcntl");
 
+	prepare_listeners(&conf);
+
 	/* fork children */
 	rde_pid = rde_main(&conf, &net_l, rules_l, &mrt_l, pipe_m2r, pipe_s2r);
 	io_pid = session_main(&conf, peer_l, &net_l, rules_l, &mrt_l,
@@ -382,6 +384,8 @@ reconfigure(char *conffile, struct bgpd_config *conf, struct mrt_head *mrt_l,
 		return (-1);
 	}
 
+	prepare_listeners(conf);
+
 	if (imsg_compose(&ibuf_se, IMSG_RECONF_CONF, 0,
 	    conf, sizeof(struct bgpd_config)) == -1)
 		return (-1);
@@ -407,7 +411,7 @@ reconfigure(char *conffile, struct bgpd_config *conf, struct mrt_head *mrt_l,
 		free(r);
 	}
 	while ((la = TAILQ_FIRST(conf->listen_addrs)) != NULL) {
-		if (imsg_compose(&ibuf_se, IMSG_RECONF_LISTENER, 0,
+		if (imsg_compose_fdpass(&ibuf_se, IMSG_RECONF_LISTENER, la->fd,
 		    la, sizeof(struct listen_addr)) == -1)
 			return (-1);
 		TAILQ_REMOVE(conf->listen_addrs, la, entry);
diff --git a/usr.sbin/bgpd/bgpd.h b/usr.sbin/bgpd/bgpd.h
index 967c45d1de2..d4d34ada083 100644
--- a/usr.sbin/bgpd/bgpd.h
+++ b/usr.sbin/bgpd/bgpd.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: bgpd.h,v 1.126 2004/06/06 17:38:10 henning Exp $ */
+/*	$OpenBSD: bgpd.h,v 1.127 2004/06/20 17:49:46 henning Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -83,6 +83,7 @@ struct buf {
 	ssize_t			 size;
 	ssize_t			 wpos;
 	ssize_t			 rpos;
+	int			 fd;
 };
 
 struct msgbuf {
@@ -109,6 +110,7 @@ struct bgpd_addr {
 };
 
 #define DEFAULT_LISTENER	0x01
+#define LISTENER_LISTENING	0x02
 
 struct listen_addr {
 	TAILQ_ENTRY(listen_addr)	 entry;
@@ -238,11 +240,17 @@ struct network {
 #define	IMSG_HEADER_SIZE	sizeof(struct imsg_hdr)
 #define	MAX_IMSGSIZE		8192
 
-struct imsgbuf {
+struct imsg_fd {
+	TAILQ_ENTRY(imsg_fd)	entry;
 	int			fd;
-	pid_t			pid;
-	struct buf_read		r;
-	struct msgbuf		w;
+};
+
+struct imsgbuf {
+	int				fd;
+	pid_t				pid;
+	TAILQ_HEAD(fds, imsg_fd)	fds;	
+	struct buf_read			r;
+	struct msgbuf			w;
 };
 
 enum imsg_type {
@@ -565,11 +573,13 @@ int	 imsg_read(struct imsgbuf *);
 int	 imsg_get(struct imsgbuf *, struct imsg *);
 int	 imsg_compose(struct imsgbuf *, int, u_int32_t, void *, u_int16_t);
 int	 imsg_compose_pid(struct imsgbuf *, int, pid_t, void *, u_int16_t);
+int	 imsg_compose_fdpass(struct imsgbuf *, int, int, void *, u_int16_t);
 struct buf *imsg_create(struct imsgbuf *, int, u_int32_t, u_int16_t);
 struct buf *imsg_create_pid(struct imsgbuf *, int, pid_t, u_int16_t);
 int	 imsg_add(struct buf *, void *, u_int16_t);
 int	 imsg_close(struct imsgbuf *, struct buf *);
 void	 imsg_free(struct imsg *);
+int	 imsg_get_fd(struct imsgbuf *);
 
 /* kroute.c */
 int	kr_init(int);
diff --git a/usr.sbin/bgpd/buffer.c b/usr.sbin/bgpd/buffer.c
index 4d91dc05434..087cc0e4f69 100644
--- a/usr.sbin/bgpd/buffer.c
+++ b/usr.sbin/bgpd/buffer.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: buffer.c,v 1.18 2004/04/29 19:56:04 deraadt Exp $ */
+/*	$OpenBSD: buffer.c,v 1.19 2004/06/20 17:49:46 henning Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -45,6 +45,7 @@ buf_open(ssize_t len)
 		return (NULL);
 	}
 	buf->size = len;
+	buf->fd = -1;
 
 	return (buf);
 }
@@ -142,17 +143,36 @@ msgbuf_write(struct msgbuf *msgbuf)
 	struct buf	*buf, *next;
 	int		 i = 0;
 	ssize_t		 n;
+	struct msghdr	 msg;
+	struct cmsghdr	*cmsg;
+	char		 cmsgbuf[CMSG_SPACE(sizeof(int))];
 
 	bzero(&iov, sizeof(iov));
+	bzero(&msg, sizeof(msg));
 	TAILQ_FOREACH(buf, &msgbuf->bufs, entries) {
 		if (i >= IOV_MAX)
 			break;
 		iov[i].iov_base = buf->buf + buf->rpos;
 		iov[i].iov_len = buf->size - buf->rpos;
 		i++;
+		if (buf->fd != -1)
+			break;
+	}
+
+	msg.msg_iov = iov;
+	msg.msg_iovlen = i;
+
+	if (buf != NULL && buf->fd != -1) {
+		msg.msg_control = (caddr_t)cmsgbuf;
+		msg.msg_controllen = CMSG_LEN(sizeof(int));
+		cmsg = CMSG_FIRSTHDR(&msg);
+		cmsg->cmsg_len = CMSG_LEN(sizeof(int));
+		cmsg->cmsg_level = SOL_SOCKET;
+		cmsg->cmsg_type = SCM_RIGHTS;
+		*(int *)CMSG_DATA(cmsg) = buf->fd;
 	}
 
-	if ((n = writev(msgbuf->fd, iov, i)) == -1) {
+	if ((n = sendmsg(msgbuf->fd, &msg, 0)) == -1) {
 		if (errno == EAGAIN)	/* cannot write immediately */
 			return (0);
 		else
@@ -164,6 +184,11 @@ msgbuf_write(struct msgbuf *msgbuf)
 		return (-2);
 	}
 
+	if (buf != NULL && buf->fd != -1) {
+		shutdown(buf->fd, SHUT_RDWR);
+		close(buf->fd);
+	}
+
 	for (buf = TAILQ_FIRST(&msgbuf->bufs); buf != NULL && n > 0;
 	    buf = next) {
 		next = TAILQ_NEXT(buf, entries);
diff --git a/usr.sbin/bgpd/config.c b/usr.sbin/bgpd/config.c
index 151f1f515a7..b5f67b8e951 100644
--- a/usr.sbin/bgpd/config.c
+++ b/usr.sbin/bgpd/config.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: config.c,v 1.38 2004/06/06 17:38:10 henning Exp $ */
+/*	$OpenBSD: config.c,v 1.39 2004/06/20 17:49:46 henning Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -224,3 +224,51 @@ host_v6(const char *s, struct bgpd_addr *h)
 
 	return (0);
 }
+
+void
+prepare_listeners(struct bgpd_config *conf)
+{
+	struct listen_addr	*la;
+	int			 opt = 1;
+
+	if (TAILQ_EMPTY(conf->listen_addrs)) {
+		if ((la = calloc(1, sizeof(struct listen_addr))) == NULL)
+			fatal("setup_listeners calloc");
+		la->fd = -1;
+		la->flags = DEFAULT_LISTENER;
+		la->sa.ss_len = sizeof(struct sockaddr_in);
+		((struct sockaddr_in *)&la->sa)->sin_family = AF_INET;
+		((struct sockaddr_in *)&la->sa)->sin_addr.s_addr =
+		    htonl(INADDR_ANY);
+		((struct sockaddr_in *)&la->sa)->sin_port = htons(BGP_PORT);
+		TAILQ_INSERT_TAIL(conf->listen_addrs, la, entry);
+
+		if ((la = calloc(1, sizeof(struct listen_addr))) == NULL)
+			fatal("setup_listeners calloc");
+		la->fd = -1;
+		la->flags = DEFAULT_LISTENER;
+		la->sa.ss_len = sizeof(struct sockaddr_in6);
+		((struct sockaddr_in6 *)&la->sa)->sin6_family = AF_INET6;
+		((struct sockaddr_in6 *)&la->sa)->sin6_port = htons(BGP_PORT);
+		TAILQ_INSERT_TAIL(conf->listen_addrs, la, entry);
+	}
+
+	TAILQ_FOREACH(la, conf->listen_addrs, entry) {
+		if ((la->fd = socket(la->sa.ss_family, SOCK_STREAM,
+		    IPPROTO_TCP)) == -1)
+			fatal("socket");
+
+		opt = 1;
+		if (setsockopt(la->fd, SOL_SOCKET, SO_REUSEPORT,
+		    &opt, sizeof(opt)) == -1)
+			fatal("setsockopt SO_REUSEPORT");
+
+		if (bind(la->fd, (struct sockaddr *)&la->sa, la->sa.ss_len) ==
+		    -1) {
+			log_warn("cannot bind to %s",
+			    log_sockaddr((struct sockaddr *)&la->sa));
+			close(la->fd);
+			la->fd = -1;
+		}
+	}
+}
diff --git a/usr.sbin/bgpd/imsg.c b/usr.sbin/bgpd/imsg.c
index eb81ad58b7b..20738c25058 100644
--- a/usr.sbin/bgpd/imsg.c
+++ b/usr.sbin/bgpd/imsg.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: imsg.c,v 1.25 2004/04/29 19:56:04 deraadt Exp $ */
+/*	$OpenBSD: imsg.c,v 1.26 2004/06/20 17:49:46 henning Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -17,6 +17,7 @@
  */
 
 #include <sys/types.h>
+#include <sys/uio.h>
 
 #include <errno.h>
 #include <stdlib.h>
@@ -26,7 +27,7 @@
 #include "bgpd.h"
 
 int		 imsg_compose_core(struct imsgbuf *, int, u_int32_t, void *,
-		     u_int16_t, pid_t);
+		     u_int16_t, pid_t, int);
 struct buf	*imsg_create_core(struct imsgbuf *, int, u_int32_t, u_int16_t,
 		     pid_t);
 
@@ -38,15 +39,29 @@ imsg_init(struct imsgbuf *ibuf, int fd)
 	ibuf->fd = fd;
 	ibuf->w.fd = fd;
 	ibuf->pid = getpid();
+	TAILQ_INIT(&ibuf->fds);
 }
 
 int
 imsg_read(struct imsgbuf *ibuf)
 {
+	struct msghdr		 msg;
+	struct cmsghdr		*cmsg;
+	char			 cmsgbuf[CMSG_SPACE(sizeof(int))];
+	struct iovec		 iov;
 	ssize_t			 n;
+	int			 fd;
+	struct imsg_fd		*ifd;
 
-	if ((n = read(ibuf->fd, ibuf->r.buf + ibuf->r.wpos,
-	    sizeof(ibuf->r.buf) - ibuf->r.wpos)) == -1) {
+	bzero(&msg, sizeof(msg));
+	iov.iov_base = ibuf->r.buf + ibuf->r.wpos;
+	iov.iov_len = sizeof(ibuf->r.buf) - ibuf->r.wpos;
+	msg.msg_iov = &iov;
+	msg.msg_iovlen = 1;
+	msg.msg_control = cmsgbuf;
+	msg.msg_controllen = sizeof(cmsgbuf);
+
+	if ((n = recvmsg(ibuf->fd, &msg, 0)) == -1) {
 		if (errno != EINTR && errno != EAGAIN) {
 			log_warn("imsg_read: pipe read error");
 			return (-1);
@@ -56,6 +71,19 @@ imsg_read(struct imsgbuf *ibuf)
 
 	ibuf->r.wpos += n;
 
+	if ((cmsg = CMSG_FIRSTHDR(&msg)) != NULL) {
+		if (cmsg->cmsg_level == SOL_SOCKET &&
+		    cmsg->cmsg_type == SCM_RIGHTS) {
+			fd = (*(int *)CMSG_DATA(cmsg));
+			if ((ifd = calloc(1, sizeof(struct imsg_fd))) == NULL)
+				fatal("imsg_read calloc");
+			ifd->fd = fd;
+			TAILQ_INSERT_TAIL(&ibuf->fds, ifd, entry);
+		} else
+			log_warn("imsg_read: got unexpected ctl data lvel %d"
+			    "type %d", cmsg->cmsg_level, cmsg->cmsg_type);
+	}
+
 	return (n);
 }
 
@@ -98,21 +126,29 @@ imsg_get(struct imsgbuf *ibuf, struct imsg *imsg)
 
 int
 imsg_compose(struct imsgbuf *ibuf, int type, u_int32_t peerid, void *data,
-    u_int16_t dlen)
+    u_int16_t datalen)
 {
-	return (imsg_compose_core(ibuf, type, peerid, data, dlen, ibuf->pid));
+	return (imsg_compose_core(ibuf, type, peerid, data, datalen,
+	    ibuf->pid, -1));
 }
 
 int
 imsg_compose_pid(struct imsgbuf *ibuf, int type, pid_t pid, void *data,
     u_int16_t datalen)
 {
-	return (imsg_compose_core(ibuf, type, 0, data, datalen, pid));
+	return (imsg_compose_core(ibuf, type, 0, data, datalen, pid, -1));
+}
+
+int
+imsg_compose_fdpass(struct imsgbuf *ibuf, int type, int fd, void *data,
+    u_int16_t datalen)
+{
+	return (imsg_compose_core(ibuf, type, 0, data, datalen, ibuf->pid, fd));
 }
 
 int
 imsg_compose_core(struct imsgbuf *ibuf, int type, u_int32_t peerid, void *data,
-    u_int16_t datalen, pid_t pid)
+    u_int16_t datalen, pid_t pid, int fd)
 {
 	struct buf	*wbuf;
 	struct imsg_hdr	 hdr;
@@ -139,6 +175,8 @@ imsg_compose_core(struct imsgbuf *ibuf, int type, u_int32_t peerid, void *data,
 			return (-1);
 		}
 
+	wbuf->fd = fd;
+
 	if ((n = buf_close(&ibuf->w, wbuf)) < 0) {
 			log_warnx("imsg_compose: buf_add error");
 			buf_free(wbuf);
@@ -213,3 +251,19 @@ imsg_free(struct imsg *imsg)
 {
 	free(imsg->data);
 }
+
+int
+imsg_get_fd(struct imsgbuf *ibuf)
+{
+	int		 fd;
+	struct imsg_fd	*ifd;
+
+	if ((ifd = TAILQ_FIRST(&ibuf->fds)) == NULL)
+		return (-1);
+
+	fd = ifd->fd;
+	TAILQ_REMOVE(&ibuf->fds, ifd, entry);
+	free(ifd);
+
+	return(fd);
+}
diff --git a/usr.sbin/bgpd/session.c b/usr.sbin/bgpd/session.c
index eee00b97f3d..1434556ade9 100644
--- a/usr.sbin/bgpd/session.c
+++ b/usr.sbin/bgpd/session.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: session.c,v 1.174 2004/06/09 13:01:44 henning Exp $ */
+/*	$OpenBSD: session.c,v 1.175 2004/06/20 17:49:46 henning Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -114,38 +114,18 @@ setup_listeners(u_int *la_cnt)
 	struct listen_addr	*la;
 	u_int			 cnt = 0;
 
-	if (TAILQ_EMPTY(conf->listen_addrs)) {
-		if ((la = calloc(1, sizeof(struct listen_addr))) == NULL)
-			fatal("setup_listeners calloc");
-		la->fd = -1;
-		la->flags = DEFAULT_LISTENER;
-		la->sa.ss_len = sizeof(struct sockaddr_in);
-		((struct sockaddr_in *)&la->sa)->sin_family = AF_INET;
-		((struct sockaddr_in *)&la->sa)->sin_addr.s_addr =
-		    htonl(INADDR_ANY);
-		((struct sockaddr_in *)&la->sa)->sin_port = htons(BGP_PORT);
-		TAILQ_INSERT_TAIL(conf->listen_addrs, la, entry);
-
-		if ((la = calloc(1, sizeof(struct listen_addr))) == NULL)
-			fatal("setup_listeners calloc");
-		la->fd = -1;
-		la->flags = DEFAULT_LISTENER;
-		la->sa.ss_len = sizeof(struct sockaddr_in6);
-		((struct sockaddr_in6 *)&la->sa)->sin6_family = AF_INET6;
-		((struct sockaddr_in6 *)&la->sa)->sin6_port = htons(BGP_PORT);
-		TAILQ_INSERT_TAIL(conf->listen_addrs, la, entry);
-	}
-
 	TAILQ_FOREACH(la, conf->listen_addrs, entry) {
 		la->reconf = RECONF_NONE;
 		cnt++;
 
-		if (la->fd != -1)
+		if (la->flags & LISTENER_LISTENING)
 			continue;
 
-		if ((la->fd = socket(la->sa.ss_family, SOCK_STREAM,
-		    IPPROTO_TCP)) == -1)
-			fatal("socket");
+		if (la->fd == -1) {
+			log_warn("cannot establish listener on %s: invalid fd",
+			    log_sockaddr((struct sockaddr *)&la->sa));
+			continue;
+		}
 
 		opt = 1;
 		if (setsockopt(la->fd, IPPROTO_TCP, TCP_MD5SIG,
@@ -157,18 +137,6 @@ setup_listeners(u_int *la_cnt)
 				fatal("setsockopt TCP_MD5SIG");
 		}
 
-		if (bind(la->fd, (struct sockaddr *)&la->sa, la->sa.ss_len) ==
-		    -1) {
-			if (errno == EACCES) {
-				log_warnx("can't establish listener on %s",
-				    log_sockaddr((struct sockaddr *)&la->sa));
-				close(la->fd);
-				la->fd = -1;
-				return (-1);
-			} else
-				fatal("bind");
-		}
-
 		session_socket_blockmode(la->fd, BM_NONBLOCK);
 
 		if (listen(la->fd, MAX_BACKLOG)) {
@@ -176,6 +144,8 @@ setup_listeners(u_int *la_cnt)
 			fatal("listen");
 		}
 
+		la->flags |= LISTENER_LISTENING;
+
 		log_info("listening on %s",
 		    log_sockaddr((struct sockaddr *)&la->sa));
 	}
@@ -234,9 +204,6 @@ session_main(struct bgpd_config *config, struct peer *cpeers,
 	setproctitle("session engine");
 	bgpd_process = PROC_SE;
 
-	listener_cnt = 0;
-	setup_listeners(&listener_cnt);
-
 	if (pfkey_init(&sysdep) == -1)
 		fatalx("pfkey setup failed");
 
@@ -247,6 +214,9 @@ session_main(struct bgpd_config *config, struct peer *cpeers,
 
 	endpwent();
 
+	listener_cnt = 0;
+	setup_listeners(&listener_cnt);
+
 	signal(SIGTERM, session_sighdlr);
 	signal(SIGINT, session_sighdlr);
 	signal(SIGPIPE, SIG_IGN);
@@ -2066,18 +2036,25 @@ session_dispatch_imsg(struct imsgbuf *ibuf, int idx, u_int *listener_cnt)
 					break;
 			}
 
+			if ((nla->fd = imsg_get_fd(ibuf)) == -1)
+				log_warnx("expected to receive fd for %s "
+				    "but didn't receive any",
+				    log_sockaddr((struct sockaddr *)&la->sa));
+
 			if (la == NULL) {
 				la = calloc(1, sizeof(struct listen_addr));
 				if (la == NULL)
 					fatal(NULL);
 				memcpy(&la->sa, &nla->sa, sizeof(la->sa));
-				la->fd = nla->fd;
 				la->flags = nla->flags;
+				la->fd = nla->fd;
 				la->reconf = RECONF_REINIT;
 				TAILQ_INSERT_TAIL(nconf->listen_addrs, la,
 				    entry);
 			} else {
 				la->reconf = RECONF_KEEP;
+				shutdown(nla->fd, SHUT_RDWR);
+				close(nla->fd);
 			}
 			break;
 		case IMSG_RECONF_DONE:
@@ -2118,6 +2095,7 @@ session_dispatch_imsg(struct imsgbuf *ibuf, int idx, u_int *listener_cnt)
 					    (struct sockaddr *)&la->sa));
 					TAILQ_REMOVE(conf->listen_addrs, la,
 					    entry);
+					shutdown(la->fd, SHUT_RDWR);
 					close(la->fd);
 					free(la);
 				}
diff --git a/usr.sbin/bgpd/session.h b/usr.sbin/bgpd/session.h
index d224198c37a..61a5a4d8951 100644
--- a/usr.sbin/bgpd/session.h
+++ b/usr.sbin/bgpd/session.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: session.h,v 1.55 2004/06/09 13:01:44 henning Exp $ */
+/*	$OpenBSD: session.h,v 1.56 2004/06/20 17:49:46 henning Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -210,6 +210,7 @@ int	 parse_config(char *, struct bgpd_config *, struct mrt_head *,
 /* config.c */
 int	 merge_config(struct bgpd_config *, struct bgpd_config *,
 	    struct peer *, struct listen_addrs *);
+void	 prepare_listeners(struct bgpd_config *);
 
 /* rde.c */
 int	 rde_main(struct bgpd_config *, struct network_head *,