[PATCH 1/2] libsupport: Add xgetpeername

[PATCH 1/2] libsupport: Add xgetpeername

[Sergey Kolosov]

The patch adds redirections for getpeername.
---
 support/Makefile       |  1 +
 support/xgetpeername.c | 30 ++++++++++++++++++++++++++++++
 support/xsocket.h      |  1 +
 3 files changed, 32 insertions(+)
 create mode 100644 support/xgetpeername.c

diff --git a/support/Makefile b/support/Makefile
index 362a51f882..aa57207bdc 100644
--- a/support/Makefile
+++ b/support/Makefile
@@ -131,6 +131,7 @@ libsupport-routines = \
   xfreopen \
   xftruncate \
   xgetline \
+  xgetpeername \
   xgetsockname \
   xlisten \
   xlseek \
diff --git a/support/xgetpeername.c b/support/xgetpeername.c
new file mode 100644
index 0000000000..6f448e456a
--- /dev/null
+++ b/support/xgetpeername.c
@@ -0,0 +1,30 @@
+/* getpeername with error checking.
+   Copyright (C) 2024 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 <support/xsocket.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <support/check.h>
+
+void
+xgetpeername (int fd, struct sockaddr *sa, socklen_t *plen)
+{
+  if (getpeername (fd, sa, plen) != 0)
+    FAIL_EXIT1 ("getpeername (%d): %m", fd);
+}
diff --git a/support/xsocket.h b/support/xsocket.h
index 3e44103546..4ac0e1f5ff 100644
--- a/support/xsocket.h
+++ b/support/xsocket.h
@@ -26,6 +26,7 @@
 int xsocket (int, int, int);
 void xsetsockopt (int, int, int, const void *, socklen_t);
 void xgetsockname (int, struct sockaddr *, socklen_t *);
+void xgetpeername (int, struct sockaddr *, socklen_t *);
 void xconnect (int, const struct sockaddr *, socklen_t);
 void xbind (int, const struct sockaddr *, socklen_t);
 void xlisten (int, int);
-- 
2.44.0

[PATCH 2/2] socket: Add new test for connect

[Sergey Kolosov]

This commit adds a new test for the connect function.
---
 socket/Makefile      |   1 +
 socket/tst-connect.c | 109 +++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 110 insertions(+)
 create mode 100644 socket/tst-connect.c

diff --git a/socket/Makefile b/socket/Makefile
index 74ca5b8452..fc1bd0a260 100644
--- a/socket/Makefile
+++ b/socket/Makefile
@@ -70,6 +70,7 @@ tests := \
   tst-accept4 \
   tst-cmsg_cloexec \
   tst-cmsghdr \
+  tst-connect \
   tst-sockopt \
   # tests
 
diff --git a/socket/tst-connect.c b/socket/tst-connect.c
new file mode 100644
index 0000000000..44999d2953
--- /dev/null
+++ b/socket/tst-connect.c
@@ -0,0 +1,109 @@
+/* Test the connect function.
+   Copyright (C) 2024 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 <arpa/inet.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <stdbool.h>
+#include <support/check.h>
+#include <support/xsocket.h>
+#include <support/xunistd.h>
+#include <sys/socket.h>
+#include <stdio.h>
+
+static struct sockaddr_in server_address;
+
+int
+open_socket (int domain, int type, int protocol)
+{
+  int fd = socket (domain, type, protocol);
+  if (fd < 0)
+  {
+    if (errno == EAFNOSUPPORT)
+      FAIL_UNSUPPORTED ("The host does not support IPv4");
+    else
+      FAIL_EXIT1 ("socket (%d, %d, %d): %m\n", domain, type, protocol);
+  }
+  return fd;
+}
+
+static pid_t
+start_server (void)
+{
+
+  server_address.sin_family = AF_INET;
+  server_address.sin_port = 0;
+  server_address.sin_addr.s_addr = htonl (INADDR_LOOPBACK);
+
+  int server_sock = open_socket (AF_INET, SOCK_STREAM, IPPROTO_TCP);
+
+  xbind (server_sock, (struct sockaddr *) &server_address,
+    sizeof (server_address));
+
+  socklen_t sa_len = sizeof (server_address);
+  xgetsockname (server_sock, (struct sockaddr *) &server_address, &sa_len);
+  printf ("Server listen on port %d\n",ntohs (server_address.sin_port));
+  xlisten (server_sock, 5);
+
+  pid_t my_pid = xfork ();
+  if (my_pid > 0)
+  {
+    xclose (server_sock);
+    return my_pid;
+  }
+
+  struct sockaddr_in client_address;
+  socklen_t ca_len = sizeof (server_address);
+  int client_sock = xaccept (server_sock,
+    (struct sockaddr *) &client_address, &ca_len);
+  printf ("socket accepted %d\n",client_sock);
+
+  _exit (0);
+}
+
+static int
+do_test (void)
+{
+  pid_t serv_pid;
+  struct sockaddr_in peer;
+  socklen_t peer_len;
+
+  serv_pid = start_server ();
+  int client_sock = open_socket (AF_INET, SOCK_STREAM, IPPROTO_TCP);
+  xconnect (client_sock, (const struct sockaddr *) &server_address,
+    sizeof (server_address));
+  int result = connect (client_sock, (const struct sockaddr *) &server_address,
+    sizeof (server_address));
+  if (result == 0  || errno != EISCONN)
+    FAIL_EXIT1 ("Second connect (%d), should fail with EISCONN: %m",
+      client_sock);
+
+  peer_len = sizeof (peer);
+  xgetpeername (client_sock, (struct sockaddr *) &peer, &peer_len);
+  TEST_COMPARE (peer_len, sizeof (peer));
+  TEST_COMPARE (peer.sin_port, server_address.sin_port);
+  TEST_COMPARE_BLOB (&peer.sin_addr, sizeof (peer.sin_addr),
+    &server_address.sin_addr, sizeof (server_address.sin_addr));
+
+  int status;
+  xwaitpid (serv_pid, &status, 0);
+  TEST_COMPARE (status, 0);
+  return 0;
+}
+#include <support/test-driver.c>
-- 
2.44.0

Re: [PATCH 1/2] libsupport: Add xgetpeername

[Arjun Shankar]

Hi Sergey,

> The patch adds redirections for getpeername.

This looks good to me.

Reviewed-by: Arjun Shankar <arjun@redhat.com>

> diff --git a/support/Makefile b/support/Makefile
> index 362a51f882..aa57207bdc 100644
> --- a/support/Makefile
> +++ b/support/Makefile
> @@ -131,6 +131,7 @@ libsupport-routines = \
>    xfreopen \
>    xftruncate \
>    xgetline \
> +  xgetpeername \
>    xgetsockname \
>    xlisten \
>    xlseek \

OK. New routine.

> diff --git a/support/xgetpeername.c b/support/xgetpeername.c
> new file mode 100644
> index 0000000000..6f448e456a
> --- /dev/null
> +++ b/support/xgetpeername.c
> @@ -0,0 +1,30 @@
> +/* getpeername with error checking.
> +   Copyright (C) 2024 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 <support/xsocket.h>
> +
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <support/check.h>
> +
> +void
> +xgetpeername (int fd, struct sockaddr *sa, socklen_t *plen)
> +{
> +  if (getpeername (fd, sa, plen) != 0)
> +    FAIL_EXIT1 ("getpeername (%d): %m", fd);
> +}

OK. I compared this with xgetsockname and it's in line with that.

> diff --git a/support/xsocket.h b/support/xsocket.h
> index 3e44103546..4ac0e1f5ff 100644
> --- a/support/xsocket.h
> +++ b/support/xsocket.h
> @@ -26,6 +26,7 @@
>  int xsocket (int, int, int);
>  void xsetsockopt (int, int, int, const void *, socklen_t);
>  void xgetsockname (int, struct sockaddr *, socklen_t *);
> +void xgetpeername (int, struct sockaddr *, socklen_t *);
>  void xconnect (int, const struct sockaddr *, socklen_t);
>  void xbind (int, const struct sockaddr *, socklen_t);
>  void xlisten (int, int);

OK.

Re: [PATCH 2/2] socket: Add new test for connect

[Arjun Shankar]

> This commit adds a new test for the connect function.

Overall, this looks fine to me. I have a couple of suggestions.

> diff --git a/socket/Makefile b/socket/Makefile
> index 74ca5b8452..fc1bd0a260 100644
> --- a/socket/Makefile
> +++ b/socket/Makefile
> @@ -70,6 +70,7 @@ tests := \
>    tst-accept4 \
>    tst-cmsg_cloexec \
>    tst-cmsghdr \
> +  tst-connect \
>    tst-sockopt \
>    # tests

OK. New test.

> diff --git a/socket/tst-connect.c b/socket/tst-connect.c
> new file mode 100644
> index 0000000000..44999d2953
> --- /dev/null
> +++ b/socket/tst-connect.c
> @@ -0,0 +1,109 @@
> +/* Test the connect function.
> +   Copyright (C) 2024 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 <arpa/inet.h>
> +#include <errno.h>
> +#include <fcntl.h>
> +#include <signal.h>
> +#include <stdbool.h>
> +#include <support/check.h>
> +#include <support/xsocket.h>
> +#include <support/xunistd.h>
> +#include <sys/socket.h>
> +#include <stdio.h>
> +
> +static struct sockaddr_in server_address;
> +
> +int
> +open_socket (int domain, int type, int protocol)
> +{
> +  int fd = socket (domain, type, protocol);
> +  if (fd < 0)
> +  {
> +    if (errno == EAFNOSUPPORT)
> +      FAIL_UNSUPPORTED ("The host does not support IPv4");

Considering we are assuming inside open_socket that we will be using
IPv4, and since both calls to open_socket are with the same args,
perhaps let's get rid of args for open_socket?

> +    else
> +      FAIL_EXIT1 ("socket (%d, %d, %d): %m\n", domain, type, protocol);
> +  }
> +  return fd;
> +}
> +
> +static pid_t
> +start_server (void)
> +{
> +
> +  server_address.sin_family = AF_INET;
> +  server_address.sin_port = 0;
> +  server_address.sin_addr.s_addr = htonl (INADDR_LOOPBACK);
> +
> +  int server_sock = open_socket (AF_INET, SOCK_STREAM, IPPROTO_TCP);
> +
> +  xbind (server_sock, (struct sockaddr *) &server_address,
> +    sizeof (server_address));
> +
> +  socklen_t sa_len = sizeof (server_address);
> +  xgetsockname (server_sock, (struct sockaddr *) &server_address, &sa_len);
> +  printf ("Server listen on port %d\n",ntohs (server_address.sin_port));
> +  xlisten (server_sock, 5);

The printf doesn't seem necessary.
OK otherwise.

> +
> +  pid_t my_pid = xfork ();
> +  if (my_pid > 0)
> +  {
> +    xclose (server_sock);
> +    return my_pid;

OK. Parent returns PID of child.

> +  }
> +
> +  struct sockaddr_in client_address;
> +  socklen_t ca_len = sizeof (server_address);
> +  int client_sock = xaccept (server_sock,
> +    (struct sockaddr *) &client_address, &ca_len);
> +  printf ("socket accepted %d\n",client_sock);
> +
> +  _exit (0);
> +}

OK. Child waits for a connection, then exits.
This printf can be skipped too.

> +
> +static int
> +do_test (void)
> +{
> +  pid_t serv_pid;
> +  struct sockaddr_in peer;
> +  socklen_t peer_len;
> +
> +  serv_pid = start_server ();
> +  int client_sock = open_socket (AF_INET, SOCK_STREAM, IPPROTO_TCP);
> +  xconnect (client_sock, (const struct sockaddr *) &server_address,
> +    sizeof (server_address));

OK.

> +  int result = connect (client_sock, (const struct sockaddr *) &server_address,
> +    sizeof (server_address));
> +  if (result == 0  || errno != EISCONN)
> +    FAIL_EXIT1 ("Second connect (%d), should fail with EISCONN: %m",
> +      client_sock);

OK. Testing that a second connect fails.
Took me a long moment to realize why there's a second connect call
right after an xconnect. Maybe worth a comment :)

> +
> +  peer_len = sizeof (peer);
> +  xgetpeername (client_sock, (struct sockaddr *) &peer, &peer_len);
> +  TEST_COMPARE (peer_len, sizeof (peer));
> +  TEST_COMPARE (peer.sin_port, server_address.sin_port);
> +  TEST_COMPARE_BLOB (&peer.sin_addr, sizeof (peer.sin_addr),
> +    &server_address.sin_addr, sizeof (server_address.sin_addr));

OK. Checking that the peer we just connected to matches the server.

> +
> +  int status;
> +  xwaitpid (serv_pid, &status, 0);
> +  TEST_COMPARE (status, 0);
> +  return 0;
> +}
> +#include <support/test-driver.c>

OK.

--
Arjun Shankar
he/him/his