From 920f5a61b9ccb37fcc307d69cc3b5a4def2f8f09 Mon Sep 17 00:00:00 2001
From: deraadt <deraadt@openbsd.org>
Date: Mon, 14 Jul 2014 04:02:33 +0000
Subject: [PATCH] Create a socketpair() and tie one end to /dev/klog using
 ioctl LIOCSFD. This allows us to receive messages direct from programs using
 the fd-safe sendsyslog(2), aka. syslog_r(3).  Thanks to guenther for this
 part of the solution. ok beck tedu miod guenther

---
 usr.sbin/syslogd/syslogd.c | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/usr.sbin/syslogd/syslogd.c b/usr.sbin/syslogd/syslogd.c
index 165100ef9a8..9d50ff51dee 100644
--- a/usr.sbin/syslogd/syslogd.c
+++ b/usr.sbin/syslogd/syslogd.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: syslogd.c,v 1.110 2014/02/04 23:28:05 bluhm Exp $	*/
+/*	$OpenBSD: syslogd.c,v 1.111 2014/07/14 04:02:33 deraadt Exp $	*/
 
 /*
  * Copyright (c) 1983, 1988, 1993, 1994
@@ -286,7 +286,7 @@ main(int argc, char *argv[])
 	socklen_t len;
 	char *p, *line;
 	char resolve[MAXHOSTNAMELEN];
-	int lockpipe[2] = { -1, -1}, nullfd;
+	int lockpipe[2] = { -1, -1}, pair[2], nullfd;
 	struct addrinfo hints, *res, *res0;
 	FILE *fp;
 
@@ -436,6 +436,14 @@ main(int argc, char *argv[])
 		pfd[PFD_UNIX_0 + i].events = POLLIN;
 	}
 
+	nfunix++;
+	if (socketpair(AF_UNIX, SOCK_DGRAM, PF_UNSPEC, pair) == -1)
+		die(0);
+	fd = pair[0];
+	double_rbuf(fd);
+	pfd[PFD_UNIX_0 + i].fd = fd;
+	pfd[PFD_UNIX_0 + i].events = POLLIN;
+
 	if (ctlsock_path != NULL) {
 		fd = unix_socket(ctlsock_path, SOCK_STREAM, 0600);
 		if (fd != -1) {
@@ -456,6 +464,10 @@ main(int argc, char *argv[])
 		pfd[PFD_KLOG].events = POLLIN;
 	}
 
+	if (ioctl(fd, LIOCSFD, &pair[1]) == -1)
+		dprintf("LIOCSFD errno %d\n", errno);
+	close(pair[1]);
+
 	dprintf("off & running....\n");
 
 	chdir("/");
-- 
2.20.1