client: Capture server stderr and send it to the logfile.

[tripe] / server / tun-linux.c

diff --git a/server/tun-linux.c b/server/tun-linux.c
index 3cfa5d72d03778362fc59eef55163f606e7d8b04..11c7f37a1667b3906253a98e9daf3319ea108f89 100644 (file)
--- a/server/tun-linux.c
+++ b/server/tun-linux.c
@@ -1,13 +1,11 @@
 /* -*-c-*-
- *
- * $Id$
  *
  * Tunnel interface based on Linux TUN/TAP driver
  *
  * (c) 2003 Straylight/Edgeware
  */
 
-/*----- Licensing notice --------------------------------------------------* 
+/*----- Licensing notice --------------------------------------------------*
  *
  * This file is part of Trivial IP Encryption (TrIPE).
  *
@@ -15,12 +13,12 @@
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
  * (at your option) any later version.
- * 
+ *
  * TrIPE 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 TrIPE; if not, write to the Free Software Foundation,
  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
@@ -46,8 +44,7 @@ struct tunnel {
   const tunnel_ops *ops;               /* Pointer to operations */
   sel_file f;                          /* Selector for TUN/TAP device */
   struct peer *p;                      /* Pointer to my peer */
-  char ifn[IFNAMSIZ];                  /* Interface name buffer */
-};  
+};
 
 /* --- @t_read@ --- *
  *
@@ -68,7 +65,7 @@ static void t_read(int fd, unsigned mode, void *v)
 
   n = read(fd, buf_i, sizeof(buf_i));
   if (n < 0) {
-    a_warn("TUN", "%s", t->ifn, "read-error", "?ERRNO", A_END);
+    a_warn("TUN", "%s", p_ifname(t->p), "read-error", "?ERRNO", A_END);
     return;
   }
   IF_TRACING(T_TUNNEL, {
@@ -91,57 +88,63 @@ static void t_read(int fd, unsigned mode, void *v)
 
 static void t_init(void) { return; }
 
-/* --- @t_create@ --- *
+/* --- @t_open@ --- *
  *
- * Arguments:  @peer *p@ = pointer to peer block
+ * Arguments:  @char **ifn@ = where to put the interface name
  *
- * Returns:    A tunnel block if it worked, or null on failure.
+ * Returns:    A file descriptor, or @-1@ on failure.
  *
- * Use:                Initializes a new tunnel.
+ * Use:                Opens a tunnel device.  This will run with root privileges
+ *             even if the rest of the server has dropped them.
  */
 
-static tunnel *t_create(peer *p)
+static int t_open(char **ifn)
 {
   int fd;
-  int f;
   struct ifreq iff;
-  tunnel *t;
 
   if ((fd = open("/dev/net/tun", O_RDWR)) < 0) {
     a_warn("TUN", "-", "linux",
-           "open-error", "/dev/net/tun", "?ERRNO",
-           A_END);
-    return (0);
+          "open-error", "/dev/net/tun", "?ERRNO",
+          A_END);
+    return (-1);
   }
-  fdflags(fd, O_NONBLOCK, O_NONBLOCK, FD_CLOEXEC, FD_CLOEXEC);
   memset(&iff, 0, sizeof(iff));
   iff.ifr_name[0] = 0;
   iff.ifr_flags = IFF_TUN | IFF_NO_PI;
-  if ((f = ioctl(fd, TUNSETIFF, &iff)) < 0) {
+  if (ioctl(fd, TUNSETIFF, &iff) < 0) {
     a_warn("TUN", "-", "linux", "config-error", "?ERRNO", A_END);
     close(fd);
-    return (0);
+    return (-1);
   }
-  t = CREATE(tunnel);
-  t->ops = &tun_linux;
-  t->p = p;
-  sel_initfile(&sel, &t->f, fd, SEL_READ, t_read, t);
-  sel_addfile(&t->f);
   iff.ifr_name[IFNAMSIZ - 1] = 0;
-  strcpy(t->ifn, iff.ifr_name);
-  T( trace(T_TUNNEL, "tun-linux: attached interface %s to peer `%s'",
-          t->ifn, p_name(p)); )
-  return (t);
+  *ifn = xstrdup(iff.ifr_name);
+  return (fd);
 }
 
-/* --- @t_ifname@ --- *
+/* --- @t_create@ --- *
  *
- * Arguments:  @tunnel *t@ = pointer to tunnel block
+ * Arguments:  @peer *p@ = pointer to peer block
+ *             @int fd@ = file descriptor of tunnel device
+ *             @char **ifn@ = where to put the interface name
+ *
+ * Returns:    A tunnel block if it worked, or null on failure.
  *
- * Returns:    A pointer to the tunnel's interface name.
+ * Use:                Initializes a new tunnel.
  */
 
-static const char *t_ifname(tunnel *t) { return (t->ifn); }
+static tunnel *t_create(peer *p, int fd, char **ifn)
+{
+  tunnel *t;
+
+  fdflags(fd, O_NONBLOCK, O_NONBLOCK, FD_CLOEXEC, FD_CLOEXEC);
+  t = CREATE(tunnel);
+  t->ops = &tun_linux;
+  t->p = p;
+  sel_initfile(&sel, &t->f, fd, SEL_READ, t_read, t);
+  sel_addfile(&t->f);
+  return (t);
+}
 
 /* --- @t_inject@ --- *
  *
@@ -172,17 +175,14 @@ static void t_inject(tunnel *t, buf *b)
  */
 
 static void t_destroy(tunnel *t)
-{
-  sel_rmfile(&t->f);
-  close(t->f.fd);
-  DESTROY(t);
-}
+  { sel_rmfile(&t->f); close(t->f.fd); DESTROY(t); }
 
 const tunnel_ops tun_linux = {
   "linux",
   t_init,
+  t_open,
   t_create,
-  t_ifname,
+  0,
   t_inject,
   t_destroy
 };