lib: privs: always look up VTY group

Even if we're running without user switch, we should still try to honor
the VTY group.  This applies both to watchquagga (which always runs as
root) as well as "no-userswitch" configurations for other daemons.

Signed-off-by: David Lamparter <equinox@opensourcerouting.org>

1 files changed, 28 insertions, 23 deletions

diff --git a/lib/privs.c b/lib/privs.c
index 6cf87c18d4..ac2a8454c5 100644
--- a/lib/privs.c
+++ b/lib/privs.c
@@ -679,6 +679,15 @@ zprivs_init(struct zebra_privs_t *zprivs)
       exit (1);
     }
 
+  if (zprivs->vty_group)
+    {
+      /* in a "NULL" setup, this is allowed to fail too, but still try. */
+      if ((grentry = getgrnam (zprivs->vty_group)))
+        zprivs_state.vtygrp = grentry->gr_gid;
+      else
+        zprivs_state.vtygrp = (gid_t)-1;
+    }
+
   /* NULL privs */
   if (! (zprivs->user || zprivs->group 
          || zprivs->cap_num_p || zprivs->cap_num_i) )
@@ -731,34 +740,30 @@ zprivs_init(struct zebra_privs_t *zprivs)
   if (zprivs->vty_group)
     /* Add the vty_group to the supplementary groups so it can be chowned to */
     {
-      if ( (grentry = getgrnam (zprivs->vty_group)) )
-        {
-          zprivs_state.vtygrp = grentry->gr_gid;
-
-          for ( i = 0; i < ngroups; i++ )
-            if ( groups[i] == zprivs_state.vtygrp )
-              {
-                found++;
-                break;
-              }
-
-          if (!found)
-            {
-	      fprintf (stderr, "privs_init: user(%s) is not part of vty group specified(%s)\n",
-		       zprivs->user, zprivs->vty_group);
-              exit (1);
-            }
-          if ( i >= ngroups && ngroups < (int) ZEBRA_NUM_OF(groups) )
-            {
-              groups[i] = zprivs_state.vtygrp;
-            }
-        }
-      else
+      if (zprivs_state.vtygrp == (gid_t)-1)
         {
           fprintf (stderr, "privs_init: could not lookup vty group %s\n",
                    zprivs->vty_group);
           exit (1);
         }
+
+      for ( i = 0; i < ngroups; i++ )
+        if ( groups[i] == zprivs_state.vtygrp )
+          {
+            found++;
+            break;
+          }
+
+      if (!found)
+        {
+          fprintf (stderr, "privs_init: user(%s) is not part of vty group specified(%s)\n",
+                   zprivs->user, zprivs->vty_group);
+          exit (1);
+        }
+      if ( i >= ngroups && ngroups < (int) ZEBRA_NUM_OF(groups) )
+        {
+          groups[i] = zprivs_state.vtygrp;
+        }
     }
 
   if (ngroups)