tests/unix_passfd: compile SOCK_STREAM and SOCK_DGRAM versions

Most test pass identically on different kinds of sockets. However,
few edge cases work differently on stream and datagram sockets. We
want to exercise this and document.

Differential revision:	https://reviews.freebsd.org/D35420

ObsoleteFiles.inc

@@ -52,6 +52,8 @@
 #   xargs -n1 | sort | uniq -d;
 # done
 
+# 20220624: unix_passfd_test -> unix_passfd_stream/unix_passfd_dgram
+OLD_FILES+=usr/tests/sys/kern/unix_passfd_test
 
 # 20220621: ISA sound card drivers removed
 OLD_FILES+=usr/share/man/man4/snd_ad1816.4

tests/sys/kern/Makefile

@@ -37,8 +37,10 @@ PLAIN_TESTS_C+=	subr_unit_test
 ATF_TESTS_C+=	sysctl_kern_proc
 ATF_TESTS_C+=	sys_getrandom
 ATF_TESTS_C+=	unix_dgram
-ATF_TESTS_C+=	unix_passfd_test
-TEST_METADATA.unix_passfd_test+=	is_exclusive="true"
+ATF_TESTS_C+=	unix_passfd_dgram
+TEST_METADATA.unix_passfd_dgram+=	is_exclusive="true"
+ATF_TESTS_C+=	unix_passfd_stream
+TEST_METADATA.unix_passfd_stream+=	is_exclusive="true"
 ATF_TESTS_C+=	unix_seqpacket_test
 TEST_METADATA.unix_seqpacket_test+=	timeout="15"
 ATF_TESTS_C+=	unix_socketpair_test

tests/sys/kern/unix_passfd_dgram.c

@@ -0,0 +1,2 @@
+#define	TEST_PROTO	SOCK_DGRAM
+#include "unix_passfd_test.c"

tests/sys/kern/unix_passfd_stream.c

@@ -0,0 +1,2 @@
+#define	TEST_PROTO	SOCK_STREAM
+#include "unix_passfd_test.c"

tests/sys/kern/unix_passfd_test.c

@@ -1,6 +1,7 @@
 /*-
  * Copyright (c) 2005 Robert N. M. Watson
  * Copyright (c) 2015 Mark Johnston
+ * Copyright (c) 2022 Gleb Smirnoff <glebius@FreeBSD.org>
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -46,6 +47,10 @@ __FBSDID("$FreeBSD$");
 
 #include <atf-c.h>
 
+#if !defined(TEST_PROTO)
+#error Need TEST_PROTO defined to SOCK_STREAM or SOCK_DGRAM
+#endif
+
 /*
  * UNIX domain sockets allow file descriptors to be passed via "ancillary
  * data", or control messages.  This regression test is intended to exercise
@@ -59,8 +64,8 @@ static void
 domainsocketpair(int *fdp)
 {
 
-	ATF_REQUIRE_MSG(socketpair(PF_UNIX, SOCK_STREAM, 0, fdp) != -1,
-	    "socketpair(PF_UNIX, SOCK_STREAM) failed: %s", strerror(errno));
+	ATF_REQUIRE_MSG(socketpair(PF_UNIX, TEST_PROTO, 0, fdp) != -1,
+	    "socketpair(PF_UNIX, %u) failed: %s", TEST_PROTO, strerror(errno));
 }
 
 static void
@@ -153,13 +158,12 @@ samefile(struct stat *sb1, struct stat *sb2)
 	ATF_REQUIRE_MSG(sb1->st_ino == sb2->st_ino, "different inode");
 }
 
-static size_t
+static ssize_t
 sendfd_payload(int sockfd, int send_fd, void *payload, size_t paylen)
 {
 	struct iovec iovec;
 	char message[CMSG_SPACE(sizeof(int))];
 	struct msghdr msghdr;
-	ssize_t len;
 
 	bzero(&msghdr, sizeof(msghdr));
 	bzero(&message, sizeof(message));
@@ -174,9 +178,7 @@ sendfd_payload(int sockfd, int send_fd, void *payload, size_t paylen)
 	msghdr.msg_iovlen = 1;
 
 	putfds(message, send_fd, 1);
-	len = sendmsg(sockfd, &msghdr, 0);
-	ATF_REQUIRE_MSG(len != -1, "sendmsg failed: %s", strerror(errno));
-	return ((size_t)len);
+	return (sendmsg(sockfd, &msghdr, 0));
 }
 
 static void
@@ -253,6 +255,9 @@ recvfd_payload(int sockfd, int *recv_fd, void *buf, size_t buflen,
 	    "recvmsg: did not receive single-fd message");
 	ATF_REQUIRE_MSG(!localcreds(sockfd) || foundcreds,
 	    "recvmsg: expected credentials were not received");
+	if (recvmsg_flags & MSG_TRUNC)
+		ATF_REQUIRE_MSG(msghdr.msg_flags & MSG_TRUNC,
+		    "recvmsg: expected MSG_TRUNC missing");
 }
 
 static void
@@ -426,13 +431,25 @@ ATF_TC_BODY(send_a_lot, tc)
 	/* Such attempt shall fail with EMSGSIZE. */
 	ATF_REQUIRE(errno == EMSGSIZE);
 	ATF_REQUIRE(getnfds() == nfds);
+#if TEST_PROTO == SOCK_STREAM
 	/*
 	 * For the SOCK_STREAM the above attempt shall free the control in
 	 * the kernel, so that socket isn't left in a stuck state.  Next read
-	 * shall bring us the normal data only.
+	 * shall bring us the normal data only.  The stream data shall not
+	 * miss a byte.
 	 */
 	ATF_REQUIRE(recvmsg(fd[1], &msghdr, 0) == 1);
 	ATF_REQUIRE(msghdr.msg_controllen == 0);
+#elif TEST_PROTO == SOCK_DGRAM
+	/*
+	 * For SOCK_DGRAM there are two options for the previously failed
+	 * syscall: strip the control leaving datagram in the socket or
+	 * drop the whole datagram.  Our implementation drops the whole
+	 * datagram.
+	 */
+	ATF_REQUIRE(recvmsg(fd[1], &msghdr, MSG_DONTWAIT) == -1);
+	ATF_REQUIRE(errno == EAGAIN);
+#endif
 }
 
 /*
@@ -514,7 +531,11 @@ ATF_TC_BODY(devfs_orphan, tc)
 	closesocketpair(fd);
 }
 
+#if TEST_PROTO == SOCK_STREAM
 #define	LOCAL_SENDSPACE_SYSCTL	"net.local.stream.sendspace"
+#elif TEST_PROTO == SOCK_DGRAM
+#define	LOCAL_SENDSPACE_SYSCTL	"net.local.dgram.maxdgram"
+#endif
 
 /*
  * Test for PR 181741. Receiver sets LOCAL_CREDS, and kernel prepends a
@@ -527,7 +548,7 @@ ATF_TC_BODY(rights_creds_payload, tc)
 {
 	const int on = 1;
 	u_long sendspace;
-	size_t len;
+	ssize_t len;
 	void *buf;
 	int fd[2], getfd, putfd, rc;
 
@@ -551,9 +572,21 @@ ATF_TC_BODY(rights_creds_payload, tc)
 	    strerror(errno));
 
 	len = sendfd_payload(fd[0], putfd, buf, sendspace);
-	ATF_REQUIRE_MSG(len < sendspace, "sendmsg: %zu bytes sent", len);
+#if TEST_PROTO == SOCK_STREAM
+	ATF_REQUIRE_MSG(len != -1 , "sendmsg failed: %s", strerror(errno));
+	ATF_REQUIRE_MSG((size_t)len < sendspace,
+	    "sendmsg: %zu bytes sent", len);
 	recvfd_payload(fd[1], &getfd, buf, len,
 	    CMSG_SPACE(SOCKCREDSIZE(CMGROUP_MAX)) + CMSG_SPACE(sizeof(int)), 0);
+#endif
+#if TEST_PROTO == SOCK_DGRAM
+	ATF_REQUIRE_MSG(len != -1 , "sendmsg failed: %s", strerror(errno));
+	ATF_REQUIRE_MSG((size_t)len == sendspace,
+	    "sendmsg: %zu bytes sent", len);
+	recvfd_payload(fd[1], &getfd, buf, len,
+	    CMSG_SPACE(SOCKCREDSIZE(CMGROUP_MAX)) + CMSG_SPACE(sizeof(int)),
+	    MSG_TRUNC);
+#endif
 
 	close(putfd);
 	close(getfd);
@@ -719,7 +752,8 @@ ATF_TC_BODY(copyout_rights_error, tc)
 	devnull(&putfd);
 	nfds = getnfds();
 
-	sendfd_payload(fd[0], putfd, buf, sizeof(buf));
+	len = sendfd_payload(fd[0], putfd, buf, sizeof(buf));
+	ATF_REQUIRE_MSG(len != -1, "sendmsg failed: %s", strerror(errno));
 
 	bzero(&msghdr, sizeof(msghdr));