diff mbox series

[v2,2/2] socket: Add socket timestamp test

Message ID 20210706145035.1657874-3-adhemerval.zanella@linaro.org
State Superseded
Headers show
Series Add test for socket timestamp | expand

Checks

Context Check Description
dj/TryBot-apply_patch success Patch applied to master at the time it was sent
dj/TryBot-32bit fail Patch caused testsuite regressions

Commit Message

Adhemerval Zanella July 6, 2021, 2:50 p.m. UTC
Changes from previous version:

  - Merged both recvmsg and recvmmsg on only one test and renamed
    to tst-socket-timestamp-time64.c.
  - Call setsockopt instead of xsetsockopt so it calls the possible
    64-bit wrapper.

---

The test check if SO_TIMESTAMP and SO_TIMESTAMPNS is correctly generated
by recvmsg and recvmmsg for both _TIME_BITS.  The recvmsg()/recvmmsg()
is called with different ancilliary data buffers, to check if the
conversion for 64-bit time on 32-bit legacy ABIs are handled correctly.

For legacy ABI with 32-bit time_t support, depending of the remmaning
ancially data space the timestamp can not be appended and MSG_TRUNC
is returned instead.

Checked on x86_64-linux and on i686-linux-gnu on both 5.11 and
4.15 kernel.
---
 sysdeps/unix/sysv/linux/Makefile              |   3 +
 .../sysv/linux/tst-socket-timestamp-time64.c  |   1 +
 .../unix/sysv/linux/tst-socket-timestamp.c    | 201 ++++++++++++++++++
 3 files changed, 205 insertions(+)
 create mode 100644 sysdeps/unix/sysv/linux/tst-socket-timestamp-time64.c
 create mode 100644 sysdeps/unix/sysv/linux/tst-socket-timestamp.c

Comments

Adhemerval Zanella July 6, 2021, 6:20 p.m. UTC | #1
On 06/07/2021 11:50, Adhemerval Zanella wrote:
> Changes from previous version:
> 
>   - Merged both recvmsg and recvmmsg on only one test and renamed
>     to tst-socket-timestamp-time64.c.
>   - Call setsockopt instead of xsetsockopt so it calls the possible
>     64-bit wrapper.
> 
> ---
> 
> The test check if SO_TIMESTAMP and SO_TIMESTAMPNS is correctly generated
> by recvmsg and recvmmsg for both _TIME_BITS.  The recvmsg()/recvmmsg()
> is called with different ancilliary data buffers, to check if the
> conversion for 64-bit time on 32-bit legacy ABIs are handled correctly.
> 
> For legacy ABI with 32-bit time_t support, depending of the remmaning
> ancially data space the timestamp can not be appended and MSG_TRUNC
> is returned instead.
> 
> Checked on x86_64-linux and on i686-linux-gnu on both 5.11 and
> 4.15 kernel.

I also noted that I haven't used support_next_to_fault_free, I will send
an update.
diff mbox series

Patch

diff --git a/sysdeps/unix/sysv/linux/Makefile b/sysdeps/unix/sysv/linux/Makefile
index faea02bd1b..509175c092 100644
--- a/sysdeps/unix/sysv/linux/Makefile
+++ b/sysdeps/unix/sysv/linux/Makefile
@@ -237,6 +237,9 @@  sysdep_routines += cmsg_nxthdr
 CFLAGS-recvmmsg.c = -fexceptions -fasynchronous-unwind-tables
 CFLAGS-sendmmsg.c = -fexceptions -fasynchronous-unwind-tables
 
+tests += tst-socket-timestamp
+tests-time64 += tst-socket-timestamp-time64
+
 tests-special += $(objpfx)tst-socket-consts.out
 $(objpfx)tst-socket-consts.out: ../sysdeps/unix/sysv/linux/tst-socket-consts.py
 	PYTHONPATH=../scripts \
diff --git a/sysdeps/unix/sysv/linux/tst-socket-timestamp-time64.c b/sysdeps/unix/sysv/linux/tst-socket-timestamp-time64.c
new file mode 100644
index 0000000000..ae424c2a70
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/tst-socket-timestamp-time64.c
@@ -0,0 +1 @@ 
+#include "tst-socket-timestamp.c"
diff --git a/sysdeps/unix/sysv/linux/tst-socket-timestamp.c b/sysdeps/unix/sysv/linux/tst-socket-timestamp.c
new file mode 100644
index 0000000000..980cca4a31
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/tst-socket-timestamp.c
@@ -0,0 +1,201 @@ 
+/* Check recvmsg/recvmmsg timestamp support.
+   Copyright (C) 2021 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <array_length.h>
+#include <arpa/inet.h>
+#include <errno.h>
+#include <string.h>
+#include <stdio.h>
+#include <support/check.h>
+#include <support/support.h>
+#include <support/xunistd.h>
+#include <support/xsocket.h>
+#include <sys/mman.h>
+
+/* Some extra space added for ancillary data, it might be used to convert
+   32-bit timestamp to 64-bit for _TIME_BITS=64 on older kernels.  */
+static const int slack[] = { 0, 4, 8, 16, 32, 64 };
+
+static size_t pagesize;
+
+static bool support_64_timestamp;
+
+static int
+do_test_send (const struct sockaddr_in *addr, int nmsgs)
+{
+  int s = xsocket (AF_INET, SOCK_DGRAM | SOCK_CLOEXEC, 0);
+  xconnect (s, (const struct sockaddr *) addr, sizeof (*addr));
+
+  for (int i = 0; i < nmsgs; i++)
+    xsendto (s, &i, sizeof (i), 0, (const struct sockaddr *) addr,
+	     sizeof (*addr));
+
+  return 0;
+}
+
+static void
+do_recvmsg (bool use_multi_call, int s, void *cmsg, size_t slack, size_t tsize,
+	    int exp_msg)
+{
+  /* A timestamp is expected if 32-bit timestamp are used (support in every
+     configuration) or if underlying kernel support 64-bit timestamps.
+     Otherwise recvmsg will need extra space do add the 64-bit timestamp.  */
+  bool exp_timestamp;
+  if (sizeof (time_t) == 4 || support_64_timestamp)
+    exp_timestamp = true;
+  else
+    exp_timestamp = slack >= CMSG_SPACE (tsize);
+
+  int msg;
+  struct iovec iov =
+    {
+      .iov_base = &msg,
+      .iov_len = sizeof (msg)
+    };
+  size_t msgs = CMSG_SPACE (tsize) + slack;
+  struct mmsghdr mmhdr =
+    {
+      .msg_hdr =
+      {
+        .msg_name = NULL,
+        .msg_namelen = 0,
+        .msg_iov = &iov,
+        .msg_iovlen = 1,
+        .msg_controllen = msgs,
+        .msg_control = cmsg != NULL ? cmsg + pagesize - msgs : NULL,
+      },
+    };
+
+  int r;
+  if (use_multi_call)
+    {
+      r = recvmmsg (s, &mmhdr, 1, 0, NULL);
+      if (r >= 0)
+	r = mmhdr.msg_len;
+    }
+  else
+    r = recvmsg (s, &mmhdr.msg_hdr, 0);
+  TEST_COMPARE (r, sizeof (int));
+  TEST_COMPARE (msg, exp_msg);
+
+  if (cmsg == NULL)
+    return;
+
+  int timestamp = false;
+  for (struct cmsghdr *cmsg = CMSG_FIRSTHDR (&mmhdr.msg_hdr);
+       cmsg != NULL;
+       cmsg = CMSG_NXTHDR (&mmhdr.msg_hdr, cmsg))
+    {
+      if (cmsg->cmsg_level != SOL_SOCKET)
+	continue;
+      if (cmsg->cmsg_type == SCM_TIMESTAMP
+	  && cmsg->cmsg_len == CMSG_LEN (sizeof (struct timeval)))
+	{
+	  struct timeval tv;
+	  memcpy (&tv, CMSG_DATA (cmsg), sizeof (tv));
+	  printf ("SCM_TIMESTAMP:   {%jd, %jd}\n", (intmax_t)tv.tv_sec,
+		  (intmax_t)tv.tv_usec);
+	  timestamp = true;
+	}
+      else if (cmsg->cmsg_type == SCM_TIMESTAMPNS
+	       && cmsg->cmsg_len == CMSG_LEN (sizeof (struct timespec)))
+	{
+	  struct timespec ts;
+	  memcpy (&ts, CMSG_DATA (cmsg), sizeof (ts));
+	  printf ("SCM_TIMESTAMPNS: {%jd, %jd}\n", (intmax_t)ts.tv_sec,
+		  (intmax_t)ts.tv_nsec);
+	  timestamp = true;
+	}
+    }
+
+  /* If there is not timestamp in the ancilliary data, recvmsg should set
+     the flag inidcating it.  */
+  if (exp_timestamp && !timestamp)
+    TEST_VERIFY (mmhdr.msg_hdr.msg_flags & MSG_TRUNC);
+  else
+    TEST_COMPARE (exp_timestamp, timestamp);
+}
+
+static int
+do_test (void)
+{
+  int srv = xsocket (AF_INET, SOCK_DGRAM, 0);
+  struct sockaddr_in srv_addr =
+    {
+      .sin_family = AF_INET,
+      .sin_addr = {.s_addr = htonl (INADDR_LOOPBACK) },
+    };
+  xbind (srv, (struct sockaddr *) &srv_addr, sizeof (srv_addr));
+  {
+    socklen_t sa_len = sizeof (srv_addr);
+    xgetsockname (srv, (struct sockaddr *) &srv_addr, &sa_len);
+    TEST_VERIFY (sa_len == sizeof (srv_addr));
+  }
+
+  TEST_COMPARE (recvmsg (-1, NULL, 0), -1);
+  TEST_COMPARE (errno, EBADF);
+  TEST_COMPARE (recvmmsg (-1, NULL, 0, 0, NULL), -1);
+  TEST_COMPARE (errno, EBADF);
+
+  /* Setup the ancillary data buffer with an extra page with PROT_NONE to
+     check the possible timestamp conversion on some systems.  */
+  pagesize = sysconf (_SC_PAGESIZE);
+  if (pagesize == -1)
+    FAIL_EXIT1 ("sysconf (_SC_PAGESIZE): %m\n");
+  void *msgbuf = xmmap (0, 2 * pagesize, PROT_NONE,
+		       	MAP_ANONYMOUS | MAP_PRIVATE, -1);
+  xmprotect (msgbuf, pagesize, PROT_READ | PROT_WRITE);
+
+  /* If underlying kernel does not support   */
+  support_64_timestamp = support_socket_time64_timestamp (srv);
+
+  /* Enable the timestamp using struct timeval precision.  */
+  {
+    int r = setsockopt (srv, SOL_SOCKET, SO_TIMESTAMP, &(int){1},
+			sizeof (int));
+    TEST_VERIFY_EXIT (r != -1);
+  }
+  /* Check recvmsg.  */
+  do_test_send (&srv_addr, array_length (slack));
+  for (int s = 0; s < array_length (slack); s++)
+    do_recvmsg (false, srv, msgbuf, slack[s], sizeof (struct timeval), s);
+  /* Check recvmmsg.  */
+  do_test_send (&srv_addr, array_length (slack));
+  for (int s = 0; s < array_length (slack); s++)
+    do_recvmsg (true, srv, msgbuf, slack[s], sizeof (struct timeval), s);
+
+  /* Now enable timestamp using a higher precision, it overwrites the previous
+     precision.  */
+  {
+    int r = setsockopt (srv, SOL_SOCKET, SO_TIMESTAMPNS, &(int){1},
+			sizeof (int));
+    TEST_VERIFY_EXIT (r != -1);
+  }
+  /* Check recvmsg.  */
+  do_test_send (&srv_addr, array_length (slack));
+  for (int s = 0; s < array_length (slack); s++)
+    do_recvmsg (false, srv, msgbuf, slack[s], sizeof (struct timespec), s);
+  /* Check recvmmsg.  */
+  do_test_send (&srv_addr, array_length (slack));
+  for (int s = 0; s < array_length (slack); s++)
+    do_recvmsg (true, srv, msgbuf, slack[s], sizeof (struct timespec), s);
+
+  return 0;
+}
+
+#include <support/test-driver.c>