commit 9321ddf3a1cae9e8f0e59b368ff3c57aed5ac1a8 Author: David Goulet dgoulet@torproject.org Date: Tue Jan 19 12:36:44 2021 -0500

config: Prioritize port with explicit address

When selecting the first advertised port, we always prefer the one with an explicit address.

Closes #40246

Signed-off-by: David Goulet dgoulet@torproject.org --- src/app/config/config.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/src/app/config/config.c b/src/app/config/config.c index d8bc5f6025..7db5e5cfa8 100644 --- a/src/app/config/config.c +++ b/src/app/config/config.c @@ -6651,20 +6651,28 @@ get_first_listener_addrport_string(int listener_type) static const port_cfg_t * portconf_get_first_advertised(int listener_type, int address_family) { + const port_cfg_t *first_port = NULL; + const port_cfg_t *first_port_explicit_addr = NULL; + if (address_family == AF_UNSPEC) return NULL;

const smartlist_t *conf_ports = get_configured_ports(); SMARTLIST_FOREACH_BEGIN(conf_ports, const port_cfg_t *, cfg) { - if (cfg->type == listener_type && - !cfg->server_cfg.no_advertise) { + if (cfg->type == listener_type && !cfg->server_cfg.no_advertise) { if ((address_family == AF_INET && port_binds_ipv4(cfg)) || (address_family == AF_INET6 && port_binds_ipv6(cfg))) { - return cfg; + if (cfg->explicit_addr && !first_port_explicit_addr) { + first_port_explicit_addr = cfg; + } else if (!first_port) { + first_port = cfg; + } } } } SMARTLIST_FOREACH_END(cfg); - return NULL; + + /* Prefer the port with the explicit address if any. */ + return (first_port_explicit_addr) ? first_port_explicit_addr : first_port; }

/** Return the first advertised port of type <b>listener_type</b> in