[RFC PATCH v2 4/6] test/vsock: rework message bounds test

[Arseniy Krasnov]

This updates message bound test making it more complex. Instead of
sending 1 bytes messages with one MSG_EOR bit, it sends messages of
random length(one half of messages are smaller than page size, second
half are bigger) with random number of MSG_EOR bits set. Receiver
also don't know total number of messages.

Signed-off-by: Arseniy Krasnov <AVKrasnov@xxxxxxxxxxxxxx>
---
 tools/testing/vsock/control.c    |  28 +++++++
 tools/testing/vsock/control.h    |   2 +
 tools/testing/vsock/util.c       |  13 ++++
 tools/testing/vsock/util.h       |   1 +
 tools/testing/vsock/vsock_test.c | 124 +++++++++++++++++++++++++++----
 5 files changed, 155 insertions(+), 13 deletions(-)

diff --git a/tools/testing/vsock/control.c b/tools/testing/vsock/control.c
index 4874872fc5a3..d2deb4b15b94 100644
--- a/tools/testing/vsock/control.c
+++ b/tools/testing/vsock/control.c
@@ -141,6 +141,34 @@ void control_writeln(const char *str)
 	timeout_end();
 }
 
+void control_writeulong(unsigned long value)
+{
+	char str[32];
+
+	if (snprintf(str, sizeof(str), "%lu", value) >= sizeof(str)) {
+		perror("snprintf");
+		exit(EXIT_FAILURE);
+	}
+
+	control_writeln(str);
+}
+
+unsigned long control_readulong(void)
+{
+	unsigned long value;
+	char *str;
+
+	str = control_readln();
+
+	if (!str)
+		exit(EXIT_FAILURE);
+
+	value = strtoul(str, NULL, 10);
+	free(str);
+
+	return value;
+}
+
 /* Return the next line from the control socket (without the trailing newline).
  *
  * The program terminates if a timeout occurs.
diff --git a/tools/testing/vsock/control.h b/tools/testing/vsock/control.h
index 51814b4f9ac1..c1f77fdb2c7a 100644
--- a/tools/testing/vsock/control.h
+++ b/tools/testing/vsock/control.h
@@ -9,7 +9,9 @@ void control_init(const char *control_host, const char *control_port,
 void control_cleanup(void);
 void control_writeln(const char *str);
 char *control_readln(void);
+unsigned long control_readulong(void);
 void control_expectln(const char *str);
 bool control_cmpln(char *line, const char *str, bool fail);
+void control_writeulong(unsigned long value);
 
 #endif /* CONTROL_H */
diff --git a/tools/testing/vsock/util.c b/tools/testing/vsock/util.c
index 2acbb7703c6a..01b636d3039a 100644
--- a/tools/testing/vsock/util.c
+++ b/tools/testing/vsock/util.c
@@ -395,3 +395,16 @@ void skip_test(struct test_case *test_cases, size_t test_cases_len,
 
 	test_cases[test_id].skip = true;
 }
+
+unsigned long hash_djb2(const void *data, size_t len)
+{
+	unsigned long hash = 5381;
+	int i = 0;
+
+	while (i < len) {
+		hash = ((hash << 5) + hash) + ((unsigned char *)data)[i];
+		i++;
+	}
+
+	return hash;
+}
diff --git a/tools/testing/vsock/util.h b/tools/testing/vsock/util.h
index a3375ad2fb7f..fb99208a95ea 100644
--- a/tools/testing/vsock/util.h
+++ b/tools/testing/vsock/util.h
@@ -49,4 +49,5 @@ void run_tests(const struct test_case *test_cases,
 void list_tests(const struct test_case *test_cases);
 void skip_test(struct test_case *test_cases, size_t test_cases_len,
 	       const char *test_id_str);
+unsigned long hash_djb2(const void *data, size_t len);
 #endif /* UTIL_H */
diff --git a/tools/testing/vsock/vsock_test.c b/tools/testing/vsock/vsock_test.c
index bb6d691cb30d..12ef0cca6f93 100644
--- a/tools/testing/vsock/vsock_test.c
+++ b/tools/testing/vsock/vsock_test.c
@@ -284,10 +284,14 @@ static void test_stream_msg_peek_server(const struct test_opts *opts)
 	close(fd);
 }
 
-#define MESSAGES_CNT 7
-#define MSG_EOR_IDX (MESSAGES_CNT / 2)
+#define SOCK_BUF_SIZE (2 * 1024 * 1024)
+#define MAX_MSG_SIZE (32 * 1024)
+
 static void test_seqpacket_msg_bounds_client(const struct test_opts *opts)
 {
+	unsigned long curr_hash;
+	int page_size;
+	int msg_count;
 	int fd;
 
 	fd = vsock_seqpacket_connect(opts->peer_cid, 1234);
@@ -296,18 +300,78 @@ static void test_seqpacket_msg_bounds_client(const struct test_opts *opts)
 		exit(EXIT_FAILURE);
 	}
 
-	/* Send several messages, one with MSG_EOR flag */
-	for (int i = 0; i < MESSAGES_CNT; i++)
-		send_byte(fd, 1, (i == MSG_EOR_IDX) ? MSG_EOR : 0);
+	/* Wait, until receiver sets buffer size. */
+	control_expectln("SRVREADY");
+
+	curr_hash = 0;
+	page_size = getpagesize();
+	msg_count = SOCK_BUF_SIZE / MAX_MSG_SIZE;
+
+	for (int i = 0; i < msg_count; i++) {
+		ssize_t send_size;
+		size_t buf_size;
+		int flags;
+		void *buf;
+
+		/* Use "small" buffers and "big" buffers. */
+		if (i & 1)
+			buf_size = page_size +
+					(rand() % (MAX_MSG_SIZE - page_size));
+		else
+			buf_size = 1 + (rand() % page_size);
+
+		buf = malloc(buf_size);
+
+		if (!buf) {
+			perror("malloc");
+			exit(EXIT_FAILURE);
+		}
+
+		/* Set at least one MSG_EOR + some random. */
+		if (i == (msg_count / 2) || (rand() & 1)) {
+			flags = MSG_EOR;
+			curr_hash++;
+		} else {
+			flags = 0;
+		}
+
+		send_size = send(fd, buf, buf_size, flags);
+
+		if (send_size < 0) {
+			perror("send");
+			exit(EXIT_FAILURE);
+		}
+
+		if (send_size != buf_size) {
+			fprintf(stderr, "Invalid send size\n");
+			exit(EXIT_FAILURE);
+		}
+
+		/*
+		 * Hash sum is computed at both client and server in
+		 * the same way: H = hash(H + 'message length'). Idea
+		 * is simple: such hash "accumulates" length and order
+		 * of every sent/received message. After data exchange,
+		 * both sums are compared using control socket, and if
+		 * message bounds wasn't broken - two values must be
+		 * equal.
+		 */
+		curr_hash += send_size;
+		curr_hash = hash_djb2(&curr_hash, sizeof(curr_hash));
+	}
 
 	control_writeln("SENDDONE");
+	control_writeulong(curr_hash);
 	close(fd);
 }
 
 static void test_seqpacket_msg_bounds_server(const struct test_opts *opts)
 {
+	unsigned long sock_buf_size;
+	unsigned long remote_hash;
+	unsigned long curr_hash;
 	int fd;
-	char buf[16];
+	char buf[MAX_MSG_SIZE];
 	struct msghdr msg = {0};
 	struct iovec iov = {0};
 
@@ -317,25 +381,58 @@ static void test_seqpacket_msg_bounds_server(const struct test_opts *opts)
 		exit(EXIT_FAILURE);
 	}
 
+	sock_buf_size = SOCK_BUF_SIZE;
+
+	if (setsockopt(fd, AF_VSOCK, SO_VM_SOCKETS_BUFFER_MAX_SIZE,
+		       &sock_buf_size, sizeof(sock_buf_size))) {
+		perror("getsockopt");
+		exit(EXIT_FAILURE);
+	}
+
+	if (setsockopt(fd, AF_VSOCK, SO_VM_SOCKETS_BUFFER_SIZE,
+		       &sock_buf_size, sizeof(sock_buf_size))) {
+		perror("getsockopt");
+		exit(EXIT_FAILURE);
+	}
+
+	/* Ready to receive data. */
+	control_writeln("SRVREADY");
+	/* Wait, until peer sends whole data. */
 	control_expectln("SENDDONE");
 	iov.iov_base = buf;
 	iov.iov_len = sizeof(buf);
 	msg.msg_iov = &iov;
 	msg.msg_iovlen = 1;
 
-	for (int i = 0; i < MESSAGES_CNT; i++) {
-		if (recvmsg(fd, &msg, 0) != 1) {
-			perror("message bound violated");
-			exit(EXIT_FAILURE);
-		}
+	curr_hash = 0;
 
-		if ((i == MSG_EOR_IDX) ^ !!(msg.msg_flags & MSG_EOR)) {
-			perror("MSG_EOR");
+	while (1) {
+		ssize_t recv_size;
+
+		recv_size = recvmsg(fd, &msg, 0);
+
+		if (!recv_size)
+			break;
+
+		if (recv_size < 0) {
+			perror("recvmsg");
 			exit(EXIT_FAILURE);
 		}
+
+		if (msg.msg_flags & MSG_EOR)
+			curr_hash++;
+
+		curr_hash += recv_size;
+		curr_hash = hash_djb2(&curr_hash, sizeof(curr_hash));
 	}
 
 	close(fd);
+	remote_hash = control_readulong();
+
+	if (curr_hash != remote_hash) {
+		fprintf(stderr, "Message bounds broken\n");
+		exit(EXIT_FAILURE);
+	}
 }
 
 #define MESSAGE_TRUNC_SZ 32
@@ -837,6 +934,7 @@ int main(int argc, char **argv)
 		.peer_cid = VMADDR_CID_ANY,
 	};
 
+	srand(time(NULL));
 	init_signals();
 
 	for (;;) {
-- 
2.25.1