[PATCH v2 0/2] Add test for socket timestamp

[PATCH v2 0/2] Add test for socket timestamp

[Adhemerval Zanella]

It tests both recvmsg and recvmmsg timestamp with different ancilliary
data sizes (to check if convertion take this in consideration), and
with different time_t sizes.
 
I checked it on x86_64-linux-gnu and i686-linux-gnu on both 
5.11 kernel and on 4.15 kernel.  I am planning to run on some
different system with different kernels as well.

Adhemerval Zanella (2):
  support: Add support_socket_time64_timestamp
  socket: Add socket timestamp test

 support/Makefile                              |   1 +
 support/support.h                             |   3 +
 support/support_socket_time64_timestamp.c     |  64 ++++++
 sysdeps/unix/sysv/linux/Makefile              |   3 +
 .../sysv/linux/tst-socket-timestamp-time64.c  |   1 +
 .../unix/sysv/linux/tst-socket-timestamp.c    | 201 ++++++++++++++++++
 6 files changed, 273 insertions(+)
 create mode 100644 support/support_socket_time64_timestamp.c
 create mode 100644 sysdeps/unix/sysv/linux/tst-socket-timestamp-time64.c
 create mode 100644 sysdeps/unix/sysv/linux/tst-socket-timestamp.c

-- 
2.30.2

[PATCH v2 1/2] support: Add support_socket_time64_timestamp

[Adhemerval Zanella]

Changes from previous version:

  - Use getsockopt instead of setsockopt.
  - Fixed socketcall fallback.

---

Check if the socket support 64-bit network packages timestamps
(SO_TIMESTAMP and SO_TIMESTAMPNS).  This will be used on recvmsg
and recvmmsg tests to check if the timestamp should be generated.
---
 support/Makefile                          |  1 +
 support/support.h                         |  3 ++
 support/support_socket_time64_timestamp.c | 64 +++++++++++++++++++++++
 3 files changed, 68 insertions(+)
 create mode 100644 support/support_socket_time64_timestamp.c

diff --git a/support/Makefile b/support/Makefile
index 5c69f0de4b..7659357b28 100644
--- a/support/Makefile
+++ b/support/Makefile
@@ -76,6 +76,7 @@ libsupport-routines = \
   support_set_small_thread_stack_size \
   support_shared_allocate \
   support_small_stack_thread_attribute \
+  support_socket_time64_timestamp \
   support_stat_nanoseconds \
   support_subprocess \
   support_test_compare_blob \
diff --git a/support/support.h b/support/support.h
index 9ec8ecb8d7..bf74a2584b 100644
--- a/support/support.h
+++ b/support/support.h
@@ -154,6 +154,9 @@ extern bool support_select_modifies_timeout (void);
    tv_usec larger than 1000000.  */
 extern bool support_select_normalizes_timeout (void);
 
+/* Return true if socket FD supports 64-bit timestamps.  */
+extern bool support_socket_time64_timestamp (int fd);
+
 /* Create a timer that trigger after SEC seconds and NSEC nanoseconds.  If
    REPEAT is true the timer will repeat indefinitely.  If CALLBACK is not
    NULL, the function will be called when the timer expires; otherwise a
diff --git a/support/support_socket_time64_timestamp.c b/support/support_socket_time64_timestamp.c
new file mode 100644
index 0000000000..a2b059a13d
--- /dev/null
+++ b/support/support_socket_time64_timestamp.c
@@ -0,0 +1,64 @@
+/* Return whether socket supports 64-bit timestamps.
+   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 <errno.h>
+#include <unistd.h>
+#include <sys/syscall.h>
+#include <sys/socket.h>
+#include <support/support.h>
+
+#ifdef __linux__
+# include <socket-constants-time64.h>
+
+static int
+__attribute_used__
+getsockopt_syscall (int fd)
+{
+  int level = SOL_SOCKET;
+  int optname = COMPAT_SO_TIMESTAMP_NEW;
+  int optval;
+  socklen_t len = sizeof (optval);
+
+  int r = syscall (__NR_getsockopt, fd, level, optname, &optval, &len);
+#  ifdef __NR_socketcall
+  if (r == -1 && errno == ENOSYS)
+    {
+      long int args[] = { fd, level, optname, (long int) &optval,
+			  sizeof (optval) };
+      r = syscall (__NR_socketcall, 15 /* SOCKOP_getsockopt  */ , args);
+    }
+#  endif
+  return r;
+}
+#endif
+
+bool
+support_socket_time64_timestamp (int fd)
+{
+#ifdef __linux__
+# if __LINUX_KERNEL_VERSION >= 0x050100                          \
+   || __WORDSIZE == 64                                           \
+   || (defined __SYSCALL_WORDSIZE && __SYSCALL_WORDSIZE == 64)
+  return true;
+# else
+  return getsockopt_syscall (fd) != -1;
+# endif
+#else
+  return false;
+#endif
+}
-- 
2.30.2

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

[Adhemerval Zanella]

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

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>
-- 
2.30.2

Re: [PATCH v2 2/2] socket: Add socket timestamp test

[Adhemerval Zanella]

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.