commit 40922629fe92a947ef3d84e71826a5030884cf08 Author: David Goulet dgoulet@torproject.org Date: Thu Jun 25 13:45:05 2020 -0400

addr: Look at /48 for IPv6 in is_local_addr()

Closes #33618

Signed-off-by: David Goulet dgoulet@torproject.org --- src/app/config/resolve_addr.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/app/config/resolve_addr.c b/src/app/config/resolve_addr.c index 15a94cb82..c8b44de84 100644 --- a/src/app/config/resolve_addr.c +++ b/src/app/config/resolve_addr.c @@ -603,8 +603,10 @@ is_local_to_resolve_addr, (const tor_addr_t *addr)) return tor_addr_compare_masked(addr, last_resolved_addr, 24, CMP_SEMANTIC) == 0; case AF_INET6: - /* Look at the /32 like addrs_in_same_network_family() does. */ - return tor_addr_compare_masked(addr, last_resolved_addr, 32, + /* Look at /48 because it is typically the smallest network in the global + * IPv6 routing tables, and it was previously the recommended per-customer + * network block. (See [RFC 6177: IPv6 End Site Address Assignment].) */ + return tor_addr_compare_masked(addr, last_resolved_addr, 48, CMP_SEMANTIC) == 0; break; default: