tests: add another test of SO_TIMESTAMP and SO_TIMESTAMPNS decoding

Unlike msg_control test, this new test makes the kernel generate
SO_TIMESTAMP and SO_TIMESTAMPNS messages.

* tests/sockopt-timestamp.c: New file.
* tests/gen_tests.in (sockopt-timestamp): New entry.
* tests/pure_executables.list: Add sockopt-timestamp.
* tests/.gitignore: Likewise.

4 files changed, 161 insertions, 0 deletions

diff --git a/tests/.gitignore b/tests/.gitignore
index 5a601641f..0d881d935 100644
--- a/tests/.gitignore
+++ b/tests/.gitignore
@@ -546,6 +546,7 @@ sockaddr_xlat-Xraw
 sockaddr_xlat-Xverbose
 socketcall
 sockopt-sol_netlink
+sockopt-timestamp
 splice
 stack-fcall
 stack-fcall-mangled
diff --git a/tests/gen_tests.in b/tests/gen_tests.in
index 314608eb2..8bdf6ba82 100644
--- a/tests/gen_tests.in
+++ b/tests/gen_tests.in
@@ -455,6 +455,7 @@ sockaddr_xlat-Xraw	-Xraw -e trace=connect
 sockaddr_xlat-Xverbose	-Xverbose -e trace=connect
 socketcall	-a20
 sockopt-sol_netlink	-e trace=getsockopt,setsockopt
+sockopt-timestamp	-e trace=recvmsg
 splice
 stat	-a32 -v -P stat.sample -P /dev/full
 stat64	-a32 -v -P stat.sample -P /dev/full
diff --git a/tests/pure_executables.list b/tests/pure_executables.list
index b695a0ece..502ce5b37 100755
--- a/tests/pure_executables.list
+++ b/tests/pure_executables.list
@@ -460,6 +460,7 @@ sockaddr_xlat-Xraw
 sockaddr_xlat-Xverbose
 socketcall
 sockopt-sol_netlink
+sockopt-timestamp
 splice
 stat
 stat64
diff --git a/tests/sockopt-timestamp.c b/tests/sockopt-timestamp.c
new file mode 100644
index 000000000..0f60d64c2
--- /dev/null
+++ b/tests/sockopt-timestamp.c
@@ -0,0 +1,158 @@
+/*
+ * Check decoding of timestamp control messages.
+ *
+ * Copyright (c) 2019 Dmitry V. Levin <ldv@altlinux.org>
+ * All rights reserved.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "tests.h"
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/socket.h>
+
+#ifndef SO_TIMESTAMP_OLD
+# define SO_TIMESTAMP_OLD SO_TIMESTAMP
+#endif
+
+#ifndef SO_TIMESTAMPNS_OLD
+# ifdef SO_TIMESTAMPNS
+#  define SO_TIMESTAMPNS_OLD SO_TIMESTAMPNS
+# endif
+#endif
+
+static void
+print_timestamp_old(const struct cmsghdr *c)
+{
+	const void *cmsg_header = c;
+	const void *cmsg_data = CMSG_DATA(c);
+	const struct timeval *tv = cmsg_data;
+	const unsigned int expected_len = sizeof(*tv);
+	const unsigned int data_len = c->cmsg_len - (cmsg_data - cmsg_header);
+
+	if (expected_len != data_len)
+		perror_msg_and_fail("sizeof(struct timeval) = %u"
+				    ", data_len = %u\n",
+				    expected_len, data_len);
+	printf("{tv_sec=%lld, tv_usec=%lld}",
+	       (long long) tv->tv_sec, (long long) tv->tv_usec);
+}
+
+#ifdef SO_TIMESTAMPNS_OLD
+static void
+print_timestampns_old(const struct cmsghdr *c)
+{
+	const void *cmsg_header = c;
+	const void *cmsg_data = CMSG_DATA(c);
+	const struct timespec *ts = cmsg_data;
+	const unsigned int expected_len = sizeof(*ts);
+	const unsigned int data_len = c->cmsg_len - (cmsg_data - cmsg_header);
+
+	if (expected_len != data_len)
+		perror_msg_and_fail("sizeof(struct timespec) = %u"
+				    ", data_len = %u\n",
+				    expected_len, data_len);
+	printf("{tv_sec=%lld, tv_nsec=%lld}",
+	       (long long) ts->tv_sec, (long long) ts->tv_nsec);
+}
+#endif /* SO_TIMESTAMPNS_OLD */
+
+static unsigned int
+test_sockopt(int so_val, const char *str, void (*fun)(const struct cmsghdr *))
+{
+	static const char data[] = "socketpair";
+	const size_t size = sizeof(data) - 1;
+
+	int sv[2];
+	if (socketpair(AF_UNIX, SOCK_DGRAM, 0, sv))
+		perror_msg_and_skip(data);
+
+	const int opt_1 = 1;
+	if (setsockopt(sv[0], SOL_SOCKET, so_val, &opt_1, sizeof(opt_1))) {
+		perror(str);
+		return 0;
+	}
+
+	if (send(sv[1], data, size, 0) != (int) size)
+		perror_msg_and_fail("send");
+	if (close(sv[1]))
+		perror_msg_and_fail("close send");
+
+	char buf[size];
+	struct iovec iov = {
+		.iov_base = buf,
+		.iov_len = sizeof(buf)
+	};
+	struct cmsghdr control[16];
+	struct msghdr mh = {
+		.msg_iov = &iov,
+		.msg_iovlen = 1,
+		.msg_control = control,
+		.msg_controllen = sizeof(control)
+	};
+
+	if (recvmsg(sv[0], &mh, 0) != (int) size)
+		perror_msg_and_fail("recvmsg");
+	if (close(sv[0]))
+		perror_msg_and_fail("close recv");
+
+	printf("recvmsg(%d, {msg_name=NULL, msg_namelen=0"
+	       ", msg_iov=[{iov_base=\"%s\", iov_len=%u}], msg_iovlen=1",
+	       sv[0], data, (unsigned int) size);
+
+	unsigned int tested = 0;
+	if (mh.msg_controllen) {
+		printf(", msg_control=[");
+		for (struct cmsghdr *c = CMSG_FIRSTHDR(&mh); c;
+		     c = CMSG_NXTHDR(&mh, c)) {
+			printf("%s{cmsg_len=%lu, cmsg_level=",
+			       (c == control ? "" : ", "),
+			       (unsigned long) c->cmsg_len);
+			if (c->cmsg_level == SOL_SOCKET) {
+				printf("SOL_SOCKET");
+			} else {
+				printf("%d", c->cmsg_level);
+			}
+			printf(", cmsg_type=");
+			if (c->cmsg_type == so_val) {
+				printf("SCM_%s, cmsg_data=", str);
+				fun(c);
+				tested = 1;
+			} else {
+				printf("%d", c->cmsg_type);
+			}
+			printf("}");
+		}
+		printf("]");
+	}
+	printf(", msg_controllen=%lu, msg_flags=0}, 0) = %u\n",
+	       (unsigned long) mh.msg_controllen, (unsigned int) size);
+
+	return tested;
+}
+
+int
+main(void)
+{
+	static const struct {
+		int val;
+		const char *str;
+		void (*fun)(const struct cmsghdr *);
+	} tests[] = {
+		{ SO_TIMESTAMP_OLD, "TIMESTAMP", print_timestamp_old },
+#ifdef SO_TIMESTAMPNS_OLD
+		{ SO_TIMESTAMPNS_OLD, "TIMESTAMPNS", print_timestampns_old },
+#endif
+	};
+	unsigned int tested = 0;
+	for (unsigned int i = 0; i < ARRAY_SIZE(tests); ++i)
+		tested |= test_sockopt(tests[i].val,
+				       tests[i].str,
+				       tests[i].fun);
+	if (!tested)
+		return 77;
+
+	puts("+++ exited with 0 +++");
+	return 0;
+}