zdtm: Add scm06 test

This test makes looped unix sockets queues and tries
to iterate over them after the restore.
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>

test/zdtm/static/Makefile

@@ -171,6 +171,7 @@ TST_NOFILE	:=				\
 		scm03				\
 		scm04				\
 		scm05				\
+		scm06				\
 		aio00				\
 		aio01				\
 		fd				\

test/zdtm/static/scm06.c

+#include <sys/resource.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <sys/epoll.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+
+#include "zdtmtst.h"
+
+const char *test_doc	= "Check a send of looped unix sockets";
+const char *test_author	= "Kirill Tkhai <ktkhai@virtuozzo.com>";
+
+static int send_fd(int via, int fd)
+{
+	struct msghdr h = {};
+	struct cmsghdr *ch;
+	struct iovec iov;
+	char buf[CMSG_SPACE(sizeof(int))];
+	char c = '\0';
+	int *fdp;
+
+	memset(buf, 0, sizeof(buf));
+	h.msg_control = buf;
+	h.msg_controllen = sizeof(buf);
+	ch = CMSG_FIRSTHDR(&h);
+	ch->cmsg_level = SOL_SOCKET;
+	ch->cmsg_type = SCM_RIGHTS;
+	ch->cmsg_len = CMSG_LEN(sizeof(int));
+	fdp = (int *)CMSG_DATA(ch);
+	fdp[0] = fd;
+
+	h.msg_iov = &iov;
+	h.msg_iovlen = 1;
+	iov.iov_base = &c;
+	iov.iov_len = sizeof(c);
+
+	if (sendmsg(via, &h, 0) <= 0)
+		return -1;
+
+	return 0;
+}
+
+static int recv_fd(int via, int *fd)
+{
+	struct msghdr h = {};
+	struct cmsghdr *ch;
+	struct iovec iov;
+	char buf[CMSG_SPACE(sizeof(int))];
+	char c;
+	int *fdp;
+
+	h.msg_control = buf;
+	h.msg_controllen = sizeof(buf);
+	h.msg_iov = &iov;
+	h.msg_iovlen = 1;
+	iov.iov_base = &c;
+	iov.iov_len = sizeof(c);
+
+	if (recvmsg(via, &h, 0) <= 0)
+		return -1;
+
+	if (h.msg_flags & MSG_CTRUNC) {
+		test_msg("CTR\n");
+		return -2;
+	}
+
+	/* No 2 SCM-s here, kernel merges them upon send */
+	ch = CMSG_FIRSTHDR(&h);
+	if (h.msg_flags & MSG_TRUNC)
+		return -2;
+	if (ch == NULL)
+		return -3;
+	if (ch->cmsg_type != SCM_RIGHTS)
+		return -4;
+
+	fdp = (int *)CMSG_DATA(ch);
+	*fd = fdp[0];
+	return 0;
+}
+
+int main(int argc, char **argv)
+{
+	int ska[2], skc, i, j, ret;
+	struct sockaddr_un addr;
+	socklen_t len;
+
+	test_init(argc, argv);
+
+	if (socketpair(PF_UNIX, SOCK_DGRAM, 0, ska) < 0) {
+		fail("Can't make unix pair");
+		exit(1);
+	}
+
+	addr.sun_family = AF_UNIX;
+	for (i = 0; i < 2; i++) {
+		addr.sun_path[0] = '\0';
+		addr.sun_path[1] = i;
+		if (bind(ska[i], (struct sockaddr *)&addr,
+			 sizeof(addr.sun_family) + 2)) {
+			fail("Can't bind");
+			exit(1);
+		}
+	}
+
+	/* Make the vinaigrette */
+	for (i = 0; i < 2; i++) {
+		for (j = 0; j < 2; j++) {
+			if (send_fd(ska[i], ska[j]) < 0) {
+				fail("Can't send sk");
+				exit(1);
+			}
+		}
+	}
+
+	test_daemon();
+	test_waitsig();
+
+	ret = -1;
+	skc = ska[0];
+	for (i = 0; i < 3; i++) {
+		if (recv_fd(skc, &skc) < 0) {
+			fail("Can't recv");
+			goto out;
+		}
+
+		len = sizeof(addr.sun_family) + 2;
+
+		if (getsockname(skc, (struct sockaddr *)&addr, &len)) {
+			fail("Can't getsockname()");
+			goto out;
+		}
+
+		if (addr.sun_path[1] != (i % 2)) {
+			fail("Wrong socket or path");
+			goto out;
+		}
+	}
+
+	pass();
+	ret = 0;
+out:
+	return ret;
+}

test/zdtm/static/scm06.desc

+{'flags': 'suid'}