secmod: fchmod socket to ug+rw

src/util/Makefile.am

@@ -39,7 +39,8 @@ CLEANFILES = \
   taler-config
 
 taler_exchange_secmod_rsa_SOURCES = \
-  taler-exchange-secmod-rsa.c taler-exchange-secmod-rsa.h
+  taler-exchange-secmod-rsa.c taler-exchange-secmod-rsa.h \
+  secmod_common.c secmod_common.h
 taler_exchange_secmod_rsa_LDADD = \
   libtalerutil.la \
   -lgnunetutil \
@@ -48,7 +49,8 @@ taler_exchange_secmod_rsa_LDADD = \
   $(XLIB)
 
 taler_exchange_secmod_eddsa_SOURCES = \
-  taler-exchange-secmod-eddsa.c taler-exchange-secmod-eddsa.h
+  taler-exchange-secmod-eddsa.c taler-exchange-secmod-eddsa.h \
+  secmod_common.c secmod_common.h
 taler_exchange_secmod_eddsa_LDADD = \
   libtalerutil.la \
   -lgnunetutil \

src/util/secmod_common.c

@@ -0,0 +1,83 @@
+/*
+  This file is part of TALER
+  Copyright (C) 2020 Taler Systems SA
+
+  TALER is free software; you can redistribute it and/or modify it under the
+  terms of the GNU General Public License as published by the Free Software
+  Foundation; either version 3, or (at your option) any later version.
+
+  TALER 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 General Public License for more details.
+
+  You should have received a copy of the GNU General Public License along with
+  TALER; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
+*/
+/**
+ * @file util/secmod_common.c
+ * @brief Common functions for the exchange security modules
+ * @author Florian Dold <dold@taler.net>
+ */
+#include "platform.h"
+#include "taler_util.h"
+#include "taler_signatures.h"
+
+struct GNUNET_NETWORK_Handle *
+TES_open_socket (const char *unixpath)
+{
+  int sock;
+
+  sock = socket (PF_UNIX,
+                 SOCK_DGRAM,
+                 0);
+  if (-1 == sock)
+  {
+    GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR,
+                         "socket");
+    return NULL;
+  }
+  /* Change permissions so that group read/writes are allowed.
+   * We need this for multi-user exchange deployment with privilege
+   * separation, where taler-exchange-httpd is part of a group
+   * that allows it to talk to secmod.
+   *
+   * Importantly, we do this before binding the socket.
+   */
+  GNUNET_assert (0 == fchmod (sock, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP));
+  {
+    struct sockaddr_un un;
+
+    if (GNUNET_OK !=
+        GNUNET_DISK_directory_create_for_file (unixpath))
+    {
+      GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_WARNING,
+                                "mkdir(dirname)",
+                                unixpath);
+    }
+    if (0 != unlink (unixpath))
+    {
+      if (ENOENT != errno)
+        GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_WARNING,
+                                  "unlink",
+                                  unixpath);
+    }
+    memset (&un,
+            0,
+            sizeof (un));
+    un.sun_family = AF_UNIX;
+    strncpy (un.sun_path,
+             unixpath,
+             sizeof (un.sun_path) - 1);
+    if (0 != bind (sock,
+                   (const struct sockaddr *) &un,
+                   sizeof (un)))
+    {
+      GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_ERROR,
+                                "bind",
+                                unixpath);
+      GNUNET_break (0 == close (sock));
+      return NULL;
+    }
+  }
+  return GNUNET_NETWORK_socket_box_native (sock);
+}

src/util/secmod_common.h

@@ -0,0 +1,36 @@
+/*
+  This file is part of GNU Taler
+  Copyright (C) 2021 Taler Systems SA
+
+  GNU Taler is free software; you can redistribute it and/or modify it under the
+  terms of the GNU General Public License as published by the Free Software
+  Foundation; either version 3, or (at your option) any later version.
+
+  GNU Taler 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 General Public License for more details.
+
+  You should have received a copy of the GNU General Public License along with
+  TALER; see the file COPYING.  If not, see
+  <http://www.gnu.org/licenses/>
+*/
+/**
+ * @file util/secmod_common.h
+ * @brief Common functions for the exchange security modules
+ * @author Florian Dold <dold@taler.net>
+ */
+#ifndef SECMOD_COMMON_H
+#define SECMOD_COMMON_H
+
+#include <gnunet/gnunet_util_lib.h>
+#include <gnunet/gnunet_network_lib.h>
+
+/**
+ * Create the listen socket for a secmod daemon.
+ *
+ * @param unixpath socket path
+ */
+struct GNUNET_NETWORK_Handle *
+TES_open_socket (const char *unixpath);
+
+#endif

src/util/taler-exchange-secmod-eddsa.c

@@ -1521,69 +1521,27 @@ run (void *cls,
     return;
   }
 
-  /* open socket */
+  if (GNUNET_OK !=
+      GNUNET_CONFIGURATION_get_value_filename (kcfg,
+                                               "taler-exchange-secmod-eddsa",
+                                               "UNIXPATH",
+                                               &unixpath))
   {
-    int sock;
+    GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
+                               "taler-exchange-secmod-eddsa",
+                               "UNIXPATH");
+    global_ret = 3;
+    return;
+  }
 
-    sock = socket (PF_UNIX,
+  GNUNET_assert (NULL != unixpath);
-                   SOCK_DGRAM,
+  unix_sock = TES_open_socket (unixpath);
-                   0);
-    if (-1 == sock)
-    {
-      GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR,
-                           "socket");
-      global_ret = 2;
-      return;
-    }
-    {
-      struct sockaddr_un un;
 
-      if (GNUNET_OK !=
+  if (NULL == unix_sock)
-          GNUNET_CONFIGURATION_get_value_filename (kcfg,
+  {
-                                                   "taler-exchange-secmod-eddsa",
+    GNUNET_free (unixpath);
-                                                   "UNIXPATH",
+    global_ret = 2;
-                                                   &unixpath))
+    return;
-      {
-        GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
-                                   "taler-exchange-secmod-eddsa",
-                                   "UNIXPATH");
-        global_ret = 3;
-        return;
-      }
-      if (GNUNET_OK !=
-          GNUNET_DISK_directory_create_for_file (unixpath))
-      {
-        GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_WARNING,
-                                  "mkdir(dirname)",
-                                  unixpath);
-      }
-      if (0 != unlink (unixpath))
-      {
-        if (ENOENT != errno)
-          GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_WARNING,
-                                    "unlink",
-                                    unixpath);
-      }
-      memset (&un,
-              0,
-              sizeof (un));
-      un.sun_family = AF_UNIX;
-      strncpy (un.sun_path,
-               unixpath,
-               sizeof (un.sun_path) - 1);
-      if (0 != bind (sock,
-                     (const struct sockaddr *) &un,
-                     sizeof (un)))
-      {
-        GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_ERROR,
-                                  "bind",
-                                  unixpath);
-        global_ret = 3;
-        GNUNET_break (0 == close (sock));
-        return;
-      }
-    }
-    unix_sock = GNUNET_NETWORK_socket_box_native (sock);
   }
 
   GNUNET_SCHEDULER_add_shutdown (&do_shutdown,
@@ -1675,7 +1633,6 @@ main (int argc,
   };
   int ret;
 
-  (void) umask (S_IWGRP | S_IROTH | S_IWOTH | S_IXOTH);
   /* force linker to link against libtalerutil; if we do
    not do this, the linker may "optimize" libtalerutil
    away and skip #TALER_OS_init(), which we do need */

src/util/taler-exchange-secmod-rsa.c

@@ -40,6 +40,7 @@
 #include <sys/eventfd.h>
 #include "taler_error_codes.h"
 #include "taler_signatures.h"
+#include "secmod_common.h"
 
 
 /**
@@ -1895,69 +1896,27 @@ run (void *cls,
     return;
   }
 
-  /* open socket */
+  if (GNUNET_OK !=
+      GNUNET_CONFIGURATION_get_value_filename (kcfg,
+                                               "taler-exchange-secmod-rsa",
+                                               "UNIXPATH",
+                                               &unixpath))
   {
-    int sock;
+    GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
+                               "taler-exchange-secmod-rsa",
+                               "UNIXPATH");
+    global_ret = 3;
+    return;
+  }
 
-    sock = socket (PF_UNIX,
+  GNUNET_assert (NULL != unixpath);
-                   SOCK_DGRAM,
+  unix_sock = TES_open_socket (unixpath);
-                   0);
-    if (-1 == sock)
-    {
-      GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR,
-                           "socket");
-      global_ret = 2;
-      return;
-    }
-    {
-      struct sockaddr_un un;
 
-      if (GNUNET_OK !=
+  if (NULL == unix_sock)
-          GNUNET_CONFIGURATION_get_value_filename (kcfg,
+  {
-                                                   "taler-exchange-secmod-rsa",
+    GNUNET_free (unixpath);
-                                                   "UNIXPATH",
+    global_ret = 2;
-                                                   &unixpath))
+    return;
-      {
-        GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
-                                   "taler-exchange-secmod-rsa",
-                                   "UNIXPATH");
-        global_ret = 3;
-        return;
-      }
-      if (GNUNET_OK !=
-          GNUNET_DISK_directory_create_for_file (unixpath))
-      {
-        GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_WARNING,
-                                  "mkdir(dirname)",
-                                  unixpath);
-      }
-      if (0 != unlink (unixpath))
-      {
-        if (ENOENT != errno)
-          GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_WARNING,
-                                    "unlink",
-                                    unixpath);
-      }
-      memset (&un,
-              0,
-              sizeof (un));
-      un.sun_family = AF_UNIX;
-      strncpy (un.sun_path,
-               unixpath,
-               sizeof (un.sun_path) - 1);
-      if (0 != bind (sock,
-                     (const struct sockaddr *) &un,
-                     sizeof (un)))
-      {
-        GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_ERROR,
-                                  "bind",
-                                  unixpath);
-        global_ret = 3;
-        GNUNET_break (0 == close (sock));
-        return;
-      }
-    }
-    unix_sock = GNUNET_NETWORK_socket_box_native (sock);
   }
 
   GNUNET_SCHEDULER_add_shutdown (&do_shutdown,