Clients connect to public relays over IPv6.

Add ClientUseIPv6 and ClientPreferIPv6ORPort configuration options.

Use "preferred OR port" for all entry nodes, not only for bridges.

Mark bridges with "prefer IPv6 OR port" if an IPv6 address is
configured in Bridge line and ClientPreferIPv6ORPort is set.

Mark relays with "prefer IPv6 OR port" if an IPv6 address is found in
descriptor and ClientPreferIPv6ORPort is set.

Filter "preferred OR port" through the ClientUseIPv6 config option. We
might want to move this test to where actual connection is being set
up once we have a fall back mechanism in place.

Have only non-servers pick an IPv6 address for the first hop: We
don't want relays to connect over IPv6 yet. (IPv6 has never been used
for second or third hops.)

Implements ticket 5535.

1 files changed, 7 insertions, 0 deletions

diff --git a/src/or/or.h b/src/or/or.h
index 00a359c533..7536afc690 100644
--- a/src/or/or.h
+++ b/src/or/or.h
@@ -3487,6 +3487,13 @@ typedef struct {
    * over randomly chosen exits. */
   int ClientRejectInternalAddresses;
 
+  /** If true, clients may connect over IPv6. XXX we don't really
+      enforce this -- clients _may_ set up outgoing IPv6 connections
+      even when this option is not set. */
+  int ClientUseIPv6;
+  /** If true, prefer an IPv6 OR port over an IPv4 one. */
+  int ClientPreferIPv6ORPort;
+
   /** The length of time that we think a consensus should be fresh. */
   int V3AuthVotingInterval;
   /** The length of time we think it will take to distribute votes. */