src/libstrongswan/networking/streams/stream_service_unix.c

   1 /*
   2  * Copyright (C) 2013 Martin Willi
   3  * Copyright (C) 2013 revosec AG
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License as published by the
   7  * Free Software Foundation; either version 2 of the License, or (at your
   8  * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  12  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  13  * for more details.
  14  */
  15
  16 #include <library.h>
  17 #include <networking/streams/stream_unix.h>
  18
  19 #include <errno.h>
  20 #include <unistd.h>
  21 #include <sys/socket.h>
  22 #include <sys/un.h>
  23 #include <sys/stat.h>
  24
  25 /**
  26  * See header
  27  */
  28 stream_service_t *stream_service_create_unix(char *uri, int backlog)
  29 {
  30         struct sockaddr_un addr;
  31         mode_t old;
  32         int fd, len;
  33
  34         len = stream_parse_uri_unix(uri, &addr);
  35         if (len == -1)
  36         {
  37                 DBG1(DBG_NET, "invalid stream URI: '%s'", uri);
  38                 return NULL;
  39         }
  40         if (!lib->caps->check(lib->caps, CAP_CHOWN))
  41         {       /* required to chown(2) service socket */
  42                 DBG1(DBG_NET, "cannot change ownership of socket '%s' without "
  43                          "CAP_CHOWN capability. socket directory should be accessible to "
  44                          "UID/GID under which the deamon will run", uri);
  45         }
  46         fd = socket(AF_UNIX, SOCK_STREAM, 0);
  47         if (fd == -1)
  48         {
  49                 DBG1(DBG_NET, "opening socket '%s' failed: %s", uri, strerror(errno));
  50                 return NULL;
  51         }
  52         unlink(addr.sun_path);
  53
  54         old = umask(S_IRWXO);
  55         if (bind(fd, (struct sockaddr*)&addr, len) < 0)
  56         {
  57                 DBG1(DBG_NET, "binding socket '%s' failed: %s", uri, strerror(errno));
  58                 close(fd);
  59                 return NULL;
  60         }
  61         umask(old);
  62         /* only attempt to chown() socket if we have CAP_CHOWN */
  63         if (lib->caps->check(lib->caps, CAP_CHOWN) &&
  64                 chown(addr.sun_path, lib->caps->get_uid(lib->caps),
  65                           lib->caps->get_gid(lib->caps)) != 0)
  66         {
  67                 DBG1(DBG_NET, "changing socket permissions for '%s' failed: %s",
  68                          uri, strerror(errno));
  69         }
  70         if (listen(fd, backlog) < 0)
  71         {
  72                 DBG1(DBG_NET, "listen on socket '%s' failed: %s", uri, strerror(errno));
  73                 unlink(addr.sun_path);
  74                 close(fd);
  75                 return NULL;
  76         }
  77         return stream_service_create_from_fd(fd);
  78 }