Backport r16450 to 0.2.0.x: open /dev/pf before dropping privileges.

svn:r16726

ChangeLog

@@ -22,6 +22,10 @@ Changes in version 0.2.0.31 - 2008-08-??
       trying session resumption at this point, but apparently some
       did, in ways that caused the handshake to fail.  Bugfix on
       0.2.0.20-rc.  Bug found by Geoff Goodell.
+    - When using the TransPort option on OpenBSD, and using the User
+      option to change UID and drop privileges, make sure to open
+      /dev/pf before dropping privileges.  Fixes bug 782.  Patch from
+      Christopher Davis.  Bugfix on 0.1.2.1-alpha.
 
 
 Changes in version 0.2.0.30 - 2008-07-15

doc/TODO.020

@@ -11,7 +11,7 @@ Backport for 0.2.0 once better tested:
   o r15821: fix bug related to TLS session negotiation.
   o r16136: prevent circid collision.  [Also backport to 0.1.2.x??]
   - r16143: generate stream close events from connection_edge_destroy().
-  - r16450: open /dev/pf before dropping privileges.
+  o r16450: open /dev/pf before dropping privileges.
   - r16605: relays reject risky extend cells.
   - r16698: don't use a new entry guard that's also your exit.
 

src/or/config.c

@@ -1022,6 +1022,16 @@ options_act_reversible(or_options_t *old_options, char **msg)
     }
   }
 
+#if defined(HAVE_NET_IF_H) && defined(HAVE_NET_PFVAR_H)
+  /* Open /dev/pf before dropping privileges. */
+  if (options->TransPort) {
+    if (get_pf_socket() < 0) {
+      *msg = tor_strdup("Unable to open /dev/pf for transparent proxy.");
+      goto rollback;
+    }
+  }
+#endif
+
   /* Setuid/setgid as appropriate */
   if (options->User || options->Group) {
     /* XXXX021 We should only do this the first time through, not on

src/or/connection_edge.c

@@ -1636,11 +1636,11 @@ connection_ap_handshake_rewrite_and_attach(edge_connection_t *conn,
 
 #ifdef TRANS_PF
 static int pf_socket = -1;
-static int
+int
 get_pf_socket(void)
 {
   int pf;
-  /*  Ideally, this should be opened before dropping privs. */
+  /* This should be opened before dropping privs. */
   if (pf_socket >= 0)
     return pf_socket;
 

src/or/or.h

@@ -2856,6 +2856,10 @@ typedef enum hostname_type_t {
 } hostname_type_t;
 hostname_type_t parse_extended_hostname(char *address);
 
+#if defined(HAVE_NET_IF_H) && defined(HAVE_NET_PFVAR_H)
+int get_pf_socket(void);
+#endif
+
 /********************************* connection_or.c ***************************/
 
 void connection_or_remove_from_identity_map(or_connection_t *conn);