[PATCH v2 1/2] libsupport: Add xgetpeername

[PATCH v2 1/2] libsupport: Add xgetpeername

[Sergey Kolosov]

The patch adds redirections for getpeername.

Reviewed-by: Arjun Shankar <arjun@redhat.com>
---
 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 v2 2/2] socket: Add new test for connect

[Sergey Kolosov]

This commit adds a simple bind/accept/connect test for an IPv4 TCP
connection to a local process via the loopback interface.
---
Changes from v1:
1. open_socket function changed to open_socket_inet_tcp one without arguments
2. removed unneeded printf
3. added comment about a second connect
---
 socket/Makefile      |   1 +
 socket/tst-connect.c | 112 +++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 113 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..50334a08df
--- /dev/null
+++ b/socket/tst-connect.c
@@ -0,0 +1,112 @@
+/* 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_inet_tcp (void)
+{
+  int fd = socket (AF_INET, SOCK_STREAM, IPPROTO_TCP);
+  if (fd < 0)
+  {
+    if (errno == EAFNOSUPPORT)
+      FAIL_UNSUPPORTED ("The host does not support IPv4");
+    else
+      FAIL_EXIT1 ("socket (AF_INET, SOCK_STREAM, IPPROTO_TCP): %m\n");
+  }
+  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_inet_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);
+  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_inet_tcp ();
+  xconnect (client_sock, (const struct sockaddr *) &server_address,
+            sizeof (server_address));
+
+  /* A second connect with same arguments should fail with EISCONN.  */
+  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