Fix LOCAL_PEERCRED with socketpair(2)

Enable the LOCAL_PEERCRED socket option for unix domain stream sockets
created with socketpair(2). Previously, it only worked with unix domain
stream sockets created with socket(2)/listen(2)/connect(2)/accept(2).

PR:		176419
Reported by:	Nicholas Wilson <nicholas@nicholaswilson.me.uk>
MFC after:	2 weeks
Differential Revision:	https://reviews.freebsd.org/D16350

2 files changed, 78 insertions, 1 deletions

diff --git a/tests/sys/kern/Makefile b/tests/sys/kern/Makefile
index 079d494b11d5..0ab4a70a41b8 100644
--- a/tests/sys/kern/Makefile
+++ b/tests/sys/kern/Makefile
@@ -12,9 +12,10 @@ TEST_METADATA.ptrace_test+=		timeout="15"
 ATF_TESTS_C+=	reaper
 PLAIN_TESTS_C+=	subr_unit_test
 ATF_TESTS_C+=	sys_getrandom
-ATF_TESTS_C+=	unix_seqpacket_test
 ATF_TESTS_C+=	unix_passfd_test
+ATF_TESTS_C+=	unix_seqpacket_test
 TEST_METADATA.unix_seqpacket_test+=	timeout="15"
+ATF_TESTS_C+=	unix_socketpair_test
 ATF_TESTS_C+=	waitpid_nohang
 ATF_TESTS_C+=	pdeathsig
 
diff --git a/tests/sys/kern/unix_socketpair_test.c b/tests/sys/kern/unix_socketpair_test.c
new file mode 100644
index 000000000000..2bcd6b7a8778
--- /dev/null
+++ b/tests/sys/kern/unix_socketpair_test.c
@@ -0,0 +1,76 @@
+/*-
+ * Copyright (c) 2018 Alan Somers
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <errno.h>
+#include <fcntl.h>
+#include <pthread.h>
+#include <signal.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+
+#include <stdio.h>
+
+#include <atf-c.h>
+
+/* getpeereid(3) should work with stream sockets created via socketpair(2) */
+ATF_TC_WITHOUT_HEAD(getpeereid);
+ATF_TC_BODY(getpeereid, tc)
+{
+	int sv[2];
+	int s;
+	uid_t real_euid, euid;
+	gid_t real_egid, egid;
+
+	real_euid = geteuid();
+	real_egid = getegid();
+
+	s = socketpair(PF_LOCAL, SOCK_STREAM, 0, sv);
+	ATF_CHECK_EQ(0, s);
+	ATF_CHECK(sv[0] >= 0);
+	ATF_CHECK(sv[1] >= 0);
+	ATF_CHECK(sv[0] != sv[1]);
+
+	ATF_REQUIRE_EQ(0, getpeereid(sv[0], &euid, &egid));
+	ATF_CHECK_EQ(real_euid, euid);
+	ATF_CHECK_EQ(real_egid, egid);
+
+	ATF_REQUIRE_EQ(0, getpeereid(sv[1], &euid, &egid));
+	ATF_CHECK_EQ(real_euid, euid);
+	ATF_CHECK_EQ(real_egid, egid);
+
+	close(sv[0]);
+	close(sv[1]);
+}
+
+
+ATF_TP_ADD_TCS(tp)
+{
+	ATF_TP_ADD_TC(tp, getpeereid);
+
+	return atf_no_error();
+}