From d7c0a19aab847e61798c666eb61111508000b838 Mon Sep 17 00:00:00 2001
From: Howard Chu <hyc@openldap.org>
Date: Wed, 4 Dec 2002 16:03:02 +0000
Subject: [PATCH] Added check for sendmsg(). Added hack to use BSD
 sendmsg()/recvmsg() to propagate peer creds if no explicit PEERCRED facility
 exists. Works on Solaris 8.

---
 configure.in                    |  1 +
 libraries/libldap/os-local.c    | 27 +++++++++++++++++++++++++++
 libraries/liblutil/getpeereid.c | 25 +++++++++++++++++++++++++
 3 files changed, 53 insertions(+)

diff --git a/configure.in b/configure.in
index f4821fde25..e0594ebed2 100644
--- a/configure.in
+++ b/configure.in
@@ -2475,6 +2475,7 @@ AC_CHECK_FUNCS(		\
 	wait4			\
 	write			\
 	send			\
+	sendmsg			\
 	sendto			\
 )
 
diff --git a/libraries/libldap/os-local.c b/libraries/libldap/os-local.c
index b752a382fe..9bd69ca92c 100644
--- a/libraries/libldap/os-local.c
+++ b/libraries/libldap/os-local.c
@@ -131,6 +131,10 @@ ldap_pvt_is_socket_ready(LDAP *ld, int s)
 }
 #undef TRACE
 
+#if !defined(HAVE_GETPEEREID) && !defined(SO_PEERCRED) && !defined(LOCAL_PEERCRED) && defined(HAVE_SENDMSG)
+#define DO_SENDMSG
+#endif
+
 static int
 ldap_pvt_connect(LDAP *ld, ber_socket_t s, struct sockaddr_un *sa, int async)
 {
@@ -155,6 +159,25 @@ ldap_pvt_connect(LDAP *ld, ber_socket_t s, struct sockaddr_un *sa, int async)
 		if ( ldap_pvt_ndelay_off(ld, s) == -1 ) {
 			return ( -1 );
 		}
+#ifdef DO_SENDMSG
+	/* Send a dummy message with access rights. Remote side will
+	 * obtain our uid/gid by fstat'ing this descriptor.
+	 */
+sendcred:	 {
+			int fds[2];
+			struct iovec iov = {(char *)fds, sizeof(int)};
+			struct msghdr msg = {0};
+			if (pipe(fds) == 0) {
+				msg.msg_iov = &iov;
+				msg.msg_iovlen = 1;
+				msg.msg_accrights = (char *)fds;
+				msg.msg_accrightslen = sizeof(int);
+				sendmsg( s, &msg, 0 );
+			    	close(fds[0]);
+				close(fds[1]);
+			}
+		}
+#endif
 		return ( 0 );
 	}
 
@@ -181,7 +204,11 @@ ldap_pvt_connect(LDAP *ld, ber_socket_t s, struct sockaddr_un *sa, int async)
 			return ( -1 );
 		if ( ldap_pvt_ndelay_off(ld, s) == -1 )
 			return ( -1 );
+#ifdef DO_SENDMSG
+		goto sendcred;
+#else
 		return ( 0 );
+#endif
 	}
 	oslocal_debug(ld, "ldap_connect_timeout: timed out\n",0,0,0);
 	ldap_pvt_set_errno( ETIMEDOUT );
diff --git a/libraries/liblutil/getpeereid.c b/libraries/liblutil/getpeereid.c
index c64c98429b..80d90d1ffe 100644
--- a/libraries/liblutil/getpeereid.c
+++ b/libraries/liblutil/getpeereid.c
@@ -18,6 +18,11 @@
 #include <sys/ucred.h>
 #endif
 
+#if !defined(SO_PEERCRED) && !defined(LOCAL_PEERCRED) && defined(HAVE_SENDMSG)
+#define DO_SENDMSG
+#include <sys/stat.h>
+#endif
+
 int getpeereid( int s, uid_t *euid, gid_t *egid )
 {
 #ifdef LDAP_PF_LOCAL
@@ -46,6 +51,26 @@ int getpeereid( int s, uid_t *euid, gid_t *egid )
 		*egid = peercred.cr_gid;
 		return 0;
 	}
+#elif defined( DO_SENDMSG )
+	int dummy, fd[2];
+	struct iovec iov = {(char *)&dummy, sizeof(dummy)};
+	struct msghdr msg = {0};
+	struct stat st;
+	msg.msg_iov = &iov;
+	msg.msg_iovlen = 1;
+	msg.msg_accrights = (char *)fd;
+	msg.msg_accrightslen = sizeof(fd);
+	if( recvmsg( s, &msg, 0) >= 0 && msg.msg_accrightslen == sizeof(int) )
+	{
+		dummy = fstat( fd, &st );
+		close(fd[0]);
+		if( dummy == 0 )
+		{
+			*euid = st.st_uid;
+			*egid = st.st_gid;
+			return 0;
+		}
+	}
 #endif
 #endif
 
-- 
2.39.5