commit 6edf7f6710600962f95e7f5458787dbc5e5c7411 Author: Nick Mathewson nickm@torproject.org Date: Wed Jun 24 14:52:44 2020 -0400

Add two new networkstatus parameters to emulate AssumeReachable.

These parameters do not suppress checks, but they tell relays that it's okay to publish even when those checks fail.

I have chosen lowercase hyphenated names, since these seem to be more common in networkstatus params.

Closes #33224 and part of #34064. --- changes/ticket34064 | 5 +++++ src/feature/nodelist/networkstatus.c | 1 + src/feature/relay/router.c | 43 ++++++++++++++++++++++++++++++++++-- src/feature/relay/router.h | 2 ++ 4 files changed, 49 insertions(+), 2 deletions(-)

diff --git a/changes/ticket34064 b/changes/ticket34064 new file mode 100644 index 000000000..13ed70c8f --- /dev/null +++ b/changes/ticket34064 @@ -0,0 +1,5 @@ + o Minor features (relay, ipv6): + - Add new "assume-reachable" and "assume-reachable-ipv6" parameters + to be used in an emergency to tell relays that they should publish + even if they cannot complete their ORPort self-checks. + Closes ticket 34064 and part of 33224. diff --git a/src/feature/nodelist/networkstatus.c b/src/feature/nodelist/networkstatus.c index 010963cda..f63d598ef 100644 --- a/src/feature/nodelist/networkstatus.c +++ b/src/feature/nodelist/networkstatus.c @@ -1698,6 +1698,7 @@ notify_after_networkstatus_changes(void) get_circuit_build_times_mutable(), c); channelpadding_new_consensus_params(c); circpad_new_consensus_params(c); + router_new_consensus_params(c); }

/** Copy all the ancillary information (like router download status and so on) diff --git a/src/feature/relay/router.c b/src/feature/relay/router.c index 1933f61ed..97b630add 100644 --- a/src/feature/relay/router.c +++ b/src/feature/relay/router.c @@ -1335,6 +1335,17 @@ should_refuse_unknown_exits(const or_options_t *options) } }

+/** + * If true, then we will publish our descriptor even if our own IPv4 ORPort + * seems to be unreachable. + **/ +static bool publish_even_when_ipv4_orport_unreachable = false; +/** + * If true, then we will publish our descriptor even if our own IPv6 ORPort + * seems to be unreachable. + **/ +static bool publish_even_when_ipv6_orport_unreachable = false; + /** Decide if we're a publishable server. We are a publishable server if: * - We don't have the ClientOnly option set * and @@ -1363,8 +1374,18 @@ decide_if_publishable_server(void) return 1; if (!router_get_advertised_or_port(options)) return 0; - if (!router_all_orports_seem_reachable(options)) - return 0; + if (!router_orport_seems_reachable(AF_INET)) { + // We have an ipv4 orport, and it doesn't seem reachable. + if (!publish_even_when_ipv4_orport_unreachable) { + return 0; + } + } + if (!router_orport_seems_reachable(AF_INET6)) { + // We have an ipv6 orport, and it doesn't seem reachable. + if (!publish_even_when_ipv6_orport_unreachable) { + return 0; + } + } if (router_have_consensus_path() == CONSENSUS_PATH_INTERNAL) { /* All set: there are no exits in the consensus (maybe this is a tiny * test network), so we can't check our DirPort reachability. */ @@ -2388,6 +2409,24 @@ router_rebuild_descriptor(int force) return 0; }

+/** Called when we have a new set of consensus parameters. */ +void +router_new_consensus_params(const networkstatus_t *ns) +{ + const int32_t DEFAULT_ASSUME_REACHABLE = 0; + const int32_t DEFAULT_ASSUME_REACHABLE_IPV6 = 0; + int ar, ar6; + ar = networkstatus_get_param(ns, + "assume-reachable", + DEFAULT_ASSUME_REACHABLE, 0, 1); + ar6 = networkstatus_get_param(ns, + "assume-reachable-ipv6", + DEFAULT_ASSUME_REACHABLE_IPV6, 0, 1); + + publish_even_when_ipv4_orport_unreachable = ar; + publish_even_when_ipv6_orport_unreachable = ar || ar6; +} + /** If our router descriptor ever goes this long without being regenerated * because something changed, we force an immediate regenerate-and-upload. */ #define FORCE_REGENERATE_DESCRIPTOR_INTERVAL (18*60*60) diff --git a/src/feature/relay/router.h b/src/feature/relay/router.h index 50790a73d..b1f90699a 100644 --- a/src/feature/relay/router.h +++ b/src/feature/relay/router.h @@ -34,6 +34,7 @@ void set_server_identity_key(crypto_pk_t *k); MOCK_DECL(crypto_pk_t *,get_server_identity_key,(void)); #else #define get_server_identity_key() (tor_abort_(),NULL) +#define router_new_consensus_params(c) ((void)(c)) #endif int server_identity_key_is_set(void); void set_client_identity_key(crypto_pk_t *k); @@ -81,6 +82,7 @@ int router_should_advertise_dirport(const or_options_t *options, void consider_publishable_server(int force); int should_refuse_unknown_exits(const or_options_t *options);

+void router_new_consensus_params(const networkstatus_t *); void router_upload_dir_desc_to_dirservers(int force); void mark_my_descriptor_dirty_if_too_old(time_t now); void mark_my_descriptor_dirty(const char *reason);