tests: (test_mkfds::sockdiag) new factory

The factory is for detecting whether a platform provides
NETLINK_SOCK_DIAG sockets for a given family.

Signed-off-by: Masatake YAMATO <yamato@redhat.com>

2 files changed, 142 insertions, 0 deletions

diff --git a/tests/helpers/test_mkfds.c b/tests/helpers/test_mkfds.c
index bbce228fd5..15e9016963 100644
--- a/tests/helpers/test_mkfds.c
+++ b/tests/helpers/test_mkfds.c
@@ -34,6 +34,8 @@
 #include <linux/if_packet.h>
 #include <linux/if_tun.h>
 #include <linux/netlink.h>
+#include <linux/sock_diag.h>
+# include <linux/unix_diag.h> /* for UNIX domain sockets */
 #include <linux/sockios.h>  /* SIOCGSKNS */
 #include <mqueue.h>
 #include <net/if.h>
@@ -70,6 +72,7 @@
 #define EXIT_ENOPROTOOPT 19
 #define EXIT_EPROTONOSUPPORT 20
 #define EXIT_EACCES 21
+#define EXIT_ENOENT 22
 
 #define _U_ __attribute__((__unused__))
 
@@ -3307,6 +3310,100 @@ static void free_mmap(const struct factory * factory _U_, void *data)
 	       ((struct mmap_data *)data)->len);
 }
 
+static int send_diag_request(int diagsd, void *req, size_t req_size)
+{
+	struct sockaddr_nl nladdr = {
+		.nl_family = AF_NETLINK,
+	};
+
+	struct nlmsghdr nlh = {
+		.nlmsg_len = sizeof(nlh) + req_size,
+		.nlmsg_type = SOCK_DIAG_BY_FAMILY,
+		.nlmsg_flags = NLM_F_REQUEST | NLM_F_DUMP,
+	};
+
+	struct iovec iovecs[] = {
+		{ &nlh, sizeof(nlh) },
+		{ req, req_size },
+	};
+
+	const struct msghdr mhd = {
+		.msg_namelen = sizeof(nladdr),
+		.msg_name = &nladdr,
+		.msg_iovlen = ARRAY_SIZE(iovecs),
+		.msg_iov = iovecs,
+	};
+
+	if (sendmsg(diagsd, &mhd, 0) < 0)
+		return errno;
+
+	return 0;
+}
+
+static void *make_sockdiag(const struct factory *factory, struct fdesc fdescs[],
+			   int argc, char ** argv)
+{
+	struct arg family = decode_arg("family", factory->params, argc, argv);
+	const char *sfamily = ARG_STRING(family);
+	int ifamily;
+	int diagsd;
+	void *req = NULL;
+	size_t reqlen = 0;
+	int e;
+	struct unix_diag_req udr;
+
+	if (strcmp(sfamily, "unix") == 0)
+		ifamily = AF_UNIX;
+	else
+		errx(EXIT_FAILURE, "unknown/unsupported family: %s", sfamily);
+	free_arg(&family);
+
+	diagsd = socket(AF_NETLINK, SOCK_DGRAM, NETLINK_SOCK_DIAG);
+	if (diagsd < 0)
+		err(errno == EPROTONOSUPPORT? EXIT_EPROTONOSUPPORT: EXIT_FAILURE,
+		    "failed in sendmsg()");
+
+	if (ifamily == AF_UNIX) {
+		udr = (struct unix_diag_req) {
+			.sdiag_family = AF_UNIX,
+			.udiag_states = -1, /* set the all bits. */
+			.udiag_show = UDIAG_SHOW_NAME | UDIAG_SHOW_PEER | UNIX_DIAG_SHUTDOWN,
+		};
+		req = &udr;
+		reqlen = sizeof(udr);
+	}
+
+	e = send_diag_request(diagsd, req, reqlen);
+	if (e) {
+		close (diagsd);
+		errno = e;
+		if (errno == EACCES)
+			err(EXIT_EACCES, "failed in sendmsg()");
+		if (errno == ENOENT)
+			err(EXIT_ENOENT, "failed in sendmsg()");
+		err(EXIT_FAILURE, "failed in sendmsg()");
+	}
+
+
+	if (diagsd != fdescs[0].fd) {
+		if (dup2(diagsd, fdescs[0].fd) < 0) {
+			e = errno;
+			close(diagsd);
+			errno = e;
+			err(EXIT_FAILURE, "failed to dup %d -> %d", diagsd, fdescs[0].fd);
+		}
+		close(diagsd);
+	}
+
+	fdescs[0] = (struct fdesc){
+		.fd    = fdescs[0].fd,
+		.close = close_fdesc,
+		.data  = NULL
+	};
+
+	return NULL;
+}
+
 #define PARAM_END { .name = NULL, }
 static const struct factory factories[] = {
 	{
@@ -4168,6 +4265,24 @@ static const struct factory factories[] = {
 			PARAM_END
 		}
 	},
+	{
+		.name = "sockdiag",
+		.desc = "make a sockdiag netlink socket",
+		.priv = false,
+		.N = 1,
+		.EX_N = 0,
+		.make = make_sockdiag,
+		.params = (struct parameter []) {
+			{
+				.name = "family",
+				.type = PTYPE_STRING,
+				/* TODO: inet, inet6 */
+				.desc = "name of a protocol family ([unix])",
+				.defv.string = "unix",
+			},
+			PARAM_END
+		}
+	},
 };
 
 static int count_parameters(const struct factory *factory)
diff --git a/tests/ts/lsfd/lsfd-functions.bash b/tests/ts/lsfd/lsfd-functions.bash
index d7eab146a7..3a3f58f0c8 100644
--- a/tests/ts/lsfd/lsfd-functions.bash
+++ b/tests/ts/lsfd/lsfd-functions.bash
@@ -20,6 +20,7 @@ readonly EPERM=18
 readonly ENOPROTOOPT=19
 readonly EPROTONOSUPPORT=20
 readonly EACCES=21
+readonly ENOENT=22
 
 function lsfd_wait_for_pausing {
 	ts_check_prog "sleep"
@@ -92,3 +93,29 @@ function lsfd_check_mkfds_factory
 		ts_skip "test_mkfds has no factory for $FACTORY"
 	fi
 }
+
+function lsfd_check_sockdiag
+{
+	local family=$1
+
+	ts_check_test_command "$TS_HELPER_MKFDS"
+
+	local msg
+	local err
+
+	msg=$("$TS_HELPER_MKFDS" -c sockdiag 9 family=$family 2>&1)
+	err=$?
+
+	case $err in
+	    0)
+		return;;
+	    $EPROTONOSUPPORT)
+		ts_skip "NETLINK_SOCK_DIAG protocol is not supported in socket(2)";;
+	    $EACCES)
+		ts_skip "sending a msg via a sockdiag netlink socket is not permitted";;
+	    $ENOENT)
+		ts_skip "sockdiag netlink socket is not available";;
+	    *)
+		ts_failed "failed to create a sockdiag netlink socket $family ($err): $msg";;
+	esac
+}