Ignore accept6/reject6 IPv4, warn about unexpected rule outcomes

When parsing torrc ExitPolicies, we now warn if:
  * an IPv4 address is used on an accept6 or reject6 line. The line is
    ignored, but the rest of the policy items in the list are used.
    (accept/reject continue to allow both IPv4 and IPv6 addresses in torrcs.)
  * a "private" address alias is used on an accept6 or reject6 line.
    The line filters both IPv4 and IPv6 private addresses, disregarding
    the 6 in accept6/reject6.

When parsing torrc ExitPolicies, we now issue an info-level message:
  * when expanding an accept/reject * line to include both IPv4 and IPv6
    wildcard addresses.

In each instance, usage advice is provided to avoid the message.

Partial fix for ticket 16069. Patch by "teor".
Patch on 2eb7eafc9d78 and a96c0affcb4c (25 Oct 2012),
released in 0.2.4.7-alpha.

1 files changed, 16 insertions, 3 deletions

diff --git a/src/or/policies.c b/src/or/policies.c
index 07a3e18597..e1d7da1f5e 100644
--- a/src/or/policies.c
+++ b/src/or/policies.c
@@ -167,6 +167,7 @@ parse_addr_policy(config_line_t *cfg, smartlist_t **dest,
   smartlist_t *result;
   smartlist_t *entries;
   addr_policy_t *item;
+  int malformed_list;
   int r = 0;
 
   if (!cfg)
@@ -179,12 +180,22 @@ parse_addr_policy(config_line_t *cfg, smartlist_t **dest,
                            SPLIT_SKIP_SPACE|SPLIT_IGNORE_BLANK, 0);
     SMARTLIST_FOREACH_BEGIN(entries, const char *, ent) {
       log_debug(LD_CONFIG,"Adding new entry '%s'",ent);
-      item = router_parse_addr_policy_item_from_string(ent, assume_action);
+      malformed_list = 0;
+      item = router_parse_addr_policy_item_from_string(ent, assume_action,
+                                                       &malformed_list);
       if (item) {
         smartlist_add(result, item);
-      } else {
-        log_warn(LD_CONFIG,"Malformed policy '%s'.", ent);
+      } else if (malformed_list) {
+        /* the error is so severe the entire list should be discarded */
+        log_warn(LD_CONFIG, "Malformed policy '%s'. Discarding entire policy "
+                 "list.", ent);
         r = -1;
+      } else {
+        /* the error is minor: don't add the item, but keep processing the
+         * rest of the policies in the list */
+        log_debug(LD_CONFIG, "Ignored policy '%s' due to non-fatal error. "
+                  "The remainder of the policy list will be used.",
+                  ent);
       }
     } SMARTLIST_FOREACH_END(ent);
     SMARTLIST_FOREACH(entries, char *, ent, tor_free(ent));
@@ -568,6 +579,8 @@ cmp_single_addr_policy(addr_policy_t *a, addr_policy_t *b)
     return r;
   if ((r=((int)a->is_private - (int)b->is_private)))
     return r;
+  /* refcnt and is_canonical are irrelevant to equality,
+   * they are hash table implementation details */
   if ((r=tor_addr_compare(&a->addr, &b->addr, CMP_EXACT)))
     return r;
   if ((r=((int)a->maskbits - (int)b->maskbits)))