selftest: af_unix: Add test for SO_INQ.

Let's add a simple test to check the basic functionality of SO_INQ.

The test does the following:

  1. Create socketpair in self->fd[]
  2. Enable SO_INQ
  3. Send data via self->fd[0]
  4. Receive data from self->fd[1]
  5. Compare the SCM_INQ cmsg with ioctl(SIOCINQ)

Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250702223606.1054680-8-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/tools/testing/selftests/net/.gitignore b/tools/testing/selftests/net/.gitignore
index c6dd2a335cf4d7bad339cd5cd1d6e885b4cf451d..47c293c2962f667745415a19edf0c057ebaa49a6 100644 (file)
--- a/tools/testing/selftests/net/.gitignore
+++ b/tools/testing/selftests/net/.gitignore
@@ -34,6 +34,7 @@ reuseport_bpf_numa
 reuseport_dualstack
 rxtimestamp
 sctp_hello
+scm_inq
 scm_pidfd
 scm_rights
 sk_bind_sendto_listen

diff --git a/tools/testing/selftests/net/af_unix/Makefile b/tools/testing/selftests/net/af_unix/Makefile
index 50584479540b0998b08dc5c1ba963554f78a2a8c..a4b61c6d029068955fcfc7b178404ff4357079cc 100644 (file)
--- a/tools/testing/selftests/net/af_unix/Makefile
+++ b/tools/testing/selftests/net/af_unix/Makefile
@@ -1,4 +1,4 @@
 CFLAGS += $(KHDR_INCLUDES)
-TEST_GEN_PROGS := diag_uid msg_oob scm_pidfd scm_rights unix_connect
+TEST_GEN_PROGS := diag_uid msg_oob scm_inq scm_pidfd scm_rights unix_connect
 
 include ../../lib.mk

diff --git a/tools/testing/selftests/net/af_unix/scm_inq.c b/tools/testing/selftests/net/af_unix/scm_inq.c
new file mode 100644 (file)
index 0000000..9d22561
--- /dev/null
+++ b/tools/testing/selftests/net/af_unix/scm_inq.c
@@ -0,0 +1,125 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright 2025 Google LLC */
+
+#include <linux/sockios.h>
+#include <sys/ioctl.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+
+#include "../../kselftest_harness.h"
+
+#define NR_CHUNKS      100
+#define MSG_LEN                256
+
+struct scm_inq {
+       struct cmsghdr cmsghdr;
+       int inq;
+};
+
+FIXTURE(scm_inq)
+{
+       int fd[2];
+};
+
+FIXTURE_VARIANT(scm_inq)
+{
+       int type;
+};
+
+FIXTURE_VARIANT_ADD(scm_inq, stream)
+{
+       .type = SOCK_STREAM,
+};
+
+FIXTURE_VARIANT_ADD(scm_inq, dgram)
+{
+       .type = SOCK_DGRAM,
+};
+
+FIXTURE_VARIANT_ADD(scm_inq, seqpacket)
+{
+       .type = SOCK_SEQPACKET,
+};
+
+FIXTURE_SETUP(scm_inq)
+{
+       int err;
+
+       err = socketpair(AF_UNIX, variant->type | SOCK_NONBLOCK, 0, self->fd);
+       ASSERT_EQ(0, err);
+}
+
+FIXTURE_TEARDOWN(scm_inq)
+{
+       close(self->fd[0]);
+       close(self->fd[1]);
+}
+
+static void send_chunks(struct __test_metadata *_metadata,
+                       FIXTURE_DATA(scm_inq) *self)
+{
+       char buf[MSG_LEN] = {};
+       int i, ret;
+
+       for (i = 0; i < NR_CHUNKS; i++) {
+               ret = send(self->fd[0], buf, sizeof(buf), 0);
+               ASSERT_EQ(sizeof(buf), ret);
+       }
+}
+
+static void recv_chunks(struct __test_metadata *_metadata,
+                       FIXTURE_DATA(scm_inq) *self)
+{
+       struct msghdr msg = {};
+       struct iovec iov = {};
+       struct scm_inq cmsg;
+       char buf[MSG_LEN];
+       int i, ret;
+       int inq;
+
+       msg.msg_iov = &iov;
+       msg.msg_iovlen = 1;
+       msg.msg_control = &cmsg;
+       msg.msg_controllen = CMSG_SPACE(sizeof(cmsg.inq));
+
+       iov.iov_base = buf;
+       iov.iov_len = sizeof(buf);
+
+       for (i = 0; i < NR_CHUNKS; i++) {
+               memset(buf, 0, sizeof(buf));
+               memset(&cmsg, 0, sizeof(cmsg));
+
+               ret = recvmsg(self->fd[1], &msg, 0);
+               ASSERT_EQ(MSG_LEN, ret);
+               ASSERT_NE(NULL, CMSG_FIRSTHDR(&msg));
+               ASSERT_EQ(CMSG_LEN(sizeof(cmsg.inq)), cmsg.cmsghdr.cmsg_len);
+               ASSERT_EQ(SOL_SOCKET, cmsg.cmsghdr.cmsg_level);
+               ASSERT_EQ(SCM_INQ, cmsg.cmsghdr.cmsg_type);
+
+               ret = ioctl(self->fd[1], SIOCINQ, &inq);
+               ASSERT_EQ(0, ret);
+               ASSERT_EQ(cmsg.inq, inq);
+       }
+}
+
+TEST_F(scm_inq, basic)
+{
+       int err, inq;
+
+       err = setsockopt(self->fd[1], SOL_SOCKET, SO_INQ, &(int){1}, sizeof(int));
+       if (variant->type != SOCK_STREAM) {
+               ASSERT_EQ(-ENOPROTOOPT, -errno);
+               return;
+       }
+
+       ASSERT_EQ(0, err);
+
+       err = ioctl(self->fd[1], SIOCINQ, &inq);
+       ASSERT_EQ(0, err);
+       ASSERT_EQ(0, inq);
+
+       send_chunks(_metadata, self);
+       recv_chunks(_metadata, self);
+}
+
+TEST_HARNESS_MAIN