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[tor/master] Do not try to download descriptors for bridges in ExcludeNodes.
by nickm＠torproject.org 27 Apr '11

27 Apr '11

commit b59a289365169cca228566826f19838403320cb2 Author: Nick Mathewson <nickm(a)torproject.org> Date: Sun Apr 3 18:12:26 2011 -0400 Do not try to download descriptors for bridges in ExcludeNodes. --- src/or/circuitbuild.c | 33 ++++++++++++++++++++++++++++++++- 1 files changed, 32 insertions(+), 1 deletions(-) diff --git a/src/or/circuitbuild.c b/src/or/circuitbuild.c index 714d636..4832cae 100644 --- a/src/or/circuitbuild.c +++ b/src/or/circuitbuild.c @@ -4539,6 +4539,24 @@ bridge_add_from_config(const tor_addr_t *addr, uint16_t port, char *digest) smartlist_add(bridge_list, b); } +/** Return true iff routerset contains the bridge bridge. */ +static int +routerset_contains_bridge(const routerset_t *routerset, + const bridge_info_t *bridge) +{ + int result; + extend_info_t *extinfo; + tor_assert(bridge); + if (!routerset) + return 0; + + extinfo = extend_info_alloc( + NULL, bridge->identity, NULL, &bridge->addr, bridge->port); + result = routerset_contains_extendinfo(routerset, extinfo); + extend_info_free(extinfo); + return result; +} + /** If digest is one of our known bridges, return it. */ static bridge_info_t * find_bridge_by_digest(const char *digest) @@ -4557,6 +4575,7 @@ static void launch_direct_bridge_descriptor_fetch(bridge_info_t *bridge) { char *address; + or_options_t *options = get_options(); if (connection_get_by_type_addr_port_purpose( CONN_TYPE_DIR, &bridge->addr, bridge->port, @@ -4564,7 +4583,13 @@ launch_direct_bridge_descriptor_fetch(bridge_info_t *bridge) return; /* it's already on the way */ address = tor_dup_addr(&bridge->addr); - /* XXX022-1090 if we ExcludeNodes this bridge, should this step fail? -RD */ + if (routerset_contains_bridge(options->ExcludeNodes, bridge)) { + download_status_mark_impossible(&bridge->fetch_status); + log_warn(LD_APP, "Not using bridge at %s: it is in ExcludeNodes.", + safe_str_client(fmt_addr(&bridge->addr))); + return; + } + directory_initiate_command(address, &bridge->addr, bridge->port, 0, 0, /* does not matter */ @@ -4605,6 +4630,12 @@ fetch_bridge_descriptors(or_options_t *options, time_t now) if (!download_status_is_ready(&bridge->fetch_status, now, IMPOSSIBLE_TO_DOWNLOAD)) continue; /* don't bother, no need to retry yet */ + if (routerset_contains_bridge(options->ExcludeNodes, bridge)) { + download_status_mark_impossible(&bridge->fetch_status); + log_warn(LD_APP, "Not using bridge at %s: it is in ExcludeNodes.", + safe_str_client(fmt_addr(&bridge->addr))); + continue; + } /* schedule another fetch as if this one will fail, in case it does */ download_status_failed(&bridge->fetch_status, 0);

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[tor/master] Do not automatically ignore Fast/Stable for exits when ExitNodes is set
by nickm＠torproject.org 27 Apr '11

27 Apr '11

commit 4851de554d5fc473cc9418b15bfb752e45b7d81d Author: Nick Mathewson <nickm(a)torproject.org> Date: Mon Mar 28 17:29:59 2011 -0400 Do not automatically ignore Fast/Stable for exits when ExitNodes is set This once maybe made sense when ExitNodes meant "Here are 3 exits; use them all", but now it more typically means "Here are 3 countries; exit from there." Using non-Fast/Stable exits created a potential partitioning opportunity and an annoying stability problem. (Don't worry about the case where all of our ExitNodes are non-Fast or non-Stable: we handle that later in the function by retrying with need_capacity and need_uptime set to 0.) --- changes/exitnodes_reliable | 7 +++++++ src/or/circuitbuild.c | 18 +++++------------- 2 files changed, 12 insertions(+), 13 deletions(-) diff --git a/changes/exitnodes_reliable b/changes/exitnodes_reliable new file mode 100644 index 0000000..62ef03a --- /dev/null +++ b/changes/exitnodes_reliable @@ -0,0 +1,7 @@ + o Minor features: + - If ExitNodes is set, still pay attention to the Fast/Stable + status of exits when picking exit nodes. (We used to ignore + these flags when ExitNodes was set, on the grounds that people + who set exitnodes wanted all of those nodes to get used, but + with the ability to pick exits by country and IP range, this + doesn't necessarily make sense any more.) diff --git a/src/or/circuitbuild.c b/src/or/circuitbuild.c index b6627a0..714d636 100644 --- a/src/or/circuitbuild.c +++ b/src/or/circuitbuild.c @@ -2697,20 +2697,12 @@ choose_good_exit_server_general(routerlist_t *dir, int need_uptime, continue; /* not one of our chosen exit nodes */ } - if (router_is_unreliable(router, need_uptime, need_capacity, 0) && - !options->ExitNodes) { - /* FFFF Someday, differentiate between a routerset that names - * routers, and a routerset that names countries, and only do this - * check if they've asked for specific exit relays. Or if the country - * they ask for is rare. Or something. */ - /* XXX022-1090 We need to pick a tradeoff here: if we throw it out because - * it's unreliable, users might end up with no exit options even - * though some options are up. If we don't throw it out, users who - * set ExitNodes will have partitioning problems because they'll be - * the only folks willing to use this node. */ + if (router_is_unreliable(router, need_uptime, need_capacity, 0)) { n_supported[i] = -1; - continue; /* skip routers that are not suitable, unless we have - * ExitNodes set, in which case we asked for it */ + continue; /* skip routers that are not suitable. Don't worry if + * this makes us reject all the possible routers: if so, + * we'll retry later in this function with need_update and + * need_capacity set to 0. */ } if (!(router->is_valid || options->_AllowInvalid & ALLOW_INVALID_EXIT)) { /* if it's invalid and we don't want it */

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[tor/master] Correct the behavior of .exit with ExcludeNodes, StrictNodes, etc.
by nickm＠torproject.org 27 Apr '11

27 Apr '11

commit ad78bafb71fbd66e83b29aba612d17f7d03e575b Author: Nick Mathewson <nickm(a)torproject.org> Date: Sun Apr 3 17:08:59 2011 -0400 Correct the behavior of .exit with ExcludeNodes, StrictNodes, etc. ExcludeExitNodes foo now means that foo.exit doesn't work. If StrictNodes is set, then ExcludeNodes foo also overrides foo.exit. foo.exit , however, still works even if foo is not listed in ExitNodes. --- src/or/connection_edge.c | 56 +++++++++++++++++++++++++++++++-------------- 1 files changed, 38 insertions(+), 18 deletions(-) diff --git a/src/or/connection_edge.c b/src/or/connection_edge.c index 1f5eb70..f435976 100644 --- a/src/or/connection_edge.c +++ b/src/or/connection_edge.c @@ -1497,9 +1497,13 @@ connection_ap_handshake_rewrite_and_attach(edge_connection_t *conn, hostname_type_t addresstype; or_options_t *options = get_options(); struct in_addr addr_tmp; + /* We set this to true if this is an address we should automatically + * remap to a local address in VirtualAddrNetwork */ int automap = 0; char orig_address[MAX_SOCKS_ADDR_LEN]; time_t map_expires = TIME_MAX; + /* This will be set to true iff the address starts out as a non-.exit + address, and we remap it to one because of an entry in the addressmap. */ int remapped_to_exit = 0; time_t now = time(NULL); @@ -1610,18 +1614,24 @@ connection_ap_handshake_rewrite_and_attach(edge_connection_t *conn, /* foo.exit -- modify conn->chosen_exit_node to specify the exit * node, and conn->address to hold only the address portion. */ char *s = strrchr(socks->address,'.'); + + /* If StrictNodes is not set, then .exit overrides ExcludeNodes. */ + routerset_t *excludeset = options->StrictNodes ? + options->_ExcludeExitNodesUnion : options->ExcludeExitNodes; + /*XXX023 make this a node_t. */ + routerinfo_t *router; + tor_assert(!automap); if (s) { + /* The address was of the form "(stuff).(name).exit */ if (s[1] != '\0') { - /* XXX022-1090 we should look this up as a relay and see if it's - * in our excluded set, and refuse it here if so. But first, - * figure out what's up with this 'remapped_to_exit' business - * and whether that needs careful treatment. -RD */ conn->chosen_exit_name = tor_strdup(s+1); + router = router_get_by_nickname(conn->chosen_exit_name, 1); if (remapped_to_exit) /* 5 tries before it expires the addressmap */ conn->chosen_exit_retries = TRACKHOSTEXITS_RETRIES; *s = 0; } else { + /* Oops, the address was (stuff)..exit. That's not okay. */ log_warn(LD_APP,"Malformed exit address '%s.exit'. Refusing.", safe_str_client(socks->address)); control_event_client_status(LOG_WARN, "SOCKS_BAD_HOSTNAME HOSTNAME=%s", @@ -1630,23 +1640,33 @@ connection_ap_handshake_rewrite_and_attach(edge_connection_t *conn, return -1; } } else { - routerinfo_t *r; + /* It looks like they just asked for "foo.exit". */ conn->chosen_exit_name = tor_strdup(socks->address); - r = router_get_by_nickname(conn->chosen_exit_name, 1); - *socks->address = 0; - if (r && (!options->_ExcludeExitNodesUnion || - !routerset_contains_router(options->_ExcludeExitNodesUnion, - r))) { - strlcpy(socks->address, r->address, sizeof(socks->address)); - } else { - log_warn(LD_APP, - "%s relay in exit address '%s.exit'. Refusing.", - r ? "Excluded" : "Unrecognized", - safe_str_client(socks->address)); - connection_mark_unattached_ap(conn, END_STREAM_REASON_TORPROTOCOL); - return -1; + router = router_get_by_nickname(conn->chosen_exit_name, 1); + if (router) { + *socks->address = 0; + strlcpy(socks->address, router->address, sizeof(socks->address)); } } + /* Now make sure that the chosen exit exists... */ + if (!router) { + log_warn(LD_APP, + "Unrecognized relay in exit address '%s.exit'. Refusing.", + safe_str_client(socks->address)); + connection_mark_unattached_ap(conn, END_STREAM_REASON_TORPROTOCOL); + return -1; + } + /* ...and make sure that it isn't excluded. */ + if (routerset_contains_router(excludeset, router)) { + log_warn(LD_APP, + "Excluded relay in exit address '%s.exit'. Refusing.", + safe_str_client(socks->address)); + connection_mark_unattached_ap(conn, END_STREAM_REASON_TORPROTOCOL); + return -1; + } + /* XXXX022-1090 Should we also allow foo.bar.exit if ExitNodes is set and + Bar is not listed in it? I say yes, but our revised manpage branch + implies no. */ } if (addresstype != ONION_HOSTNAME) {

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[tor/master] Simplify calls to routerset_equal
by nickm＠torproject.org 27 Apr '11

27 Apr '11

commit 128582cc1f9fd363f3fb2a96b61fde1701a56970 Author: Nick Mathewson <nickm(a)torproject.org> Date: Sun Apr 3 19:13:36 2011 -0400 Simplify calls to routerset_equal The routerset_equal function explicitly handles NULL inputs, so there's no need to check inputs for NULL before calling it. Also fix a bug in routerset_equal where a non-NULL routerset with no entries didn't get counted as equal to a NULL routerset. This was untriggerable, I think, but potentially annoying down the road. --- src/or/config.c | 14 +++++--------- src/or/routerlist.c | 11 +++++++---- 2 files changed, 12 insertions(+), 13 deletions(-) diff --git a/src/or/config.c b/src/or/config.c index 404e648..44cde85 100644 --- a/src/or/config.c +++ b/src/or/config.c @@ -1260,15 +1260,11 @@ options_act(or_options_t *old_options) /* Check for transitions that need action. */ if (old_options) { if ((options->UseEntryGuards && !old_options->UseEntryGuards) || - (options->ExcludeNodes && - !routerset_equal(old_options->ExcludeNodes,options->ExcludeNodes)) || - (options->ExcludeExitNodes && - !routerset_equal(old_options->ExcludeExitNodes, - options->ExcludeExitNodes)) || - (options->EntryNodes && - !routerset_equal(old_options->EntryNodes, options->EntryNodes)) || - (options->ExitNodes && - !routerset_equal(old_options->ExitNodes, options->ExitNodes)) || + !routerset_equal(old_options->ExcludeNodes,options->ExcludeNodes) || + !routerset_equal(old_options->ExcludeExitNodes, + options->ExcludeExitNodes) || + !routerset_equal(old_options->EntryNodes, options->EntryNodes) || + !routerset_equal(old_options->ExitNodes, options->ExitNodes) || options->StrictNodes != old_options->StrictNodes) { log_info(LD_CIRC, "Changed to using entry guards, or changed preferred or " diff --git a/src/or/routerlist.c b/src/or/routerlist.c index a9a216b..d5e8a6b 100644 --- a/src/or/routerlist.c +++ b/src/or/routerlist.c @@ -5473,14 +5473,12 @@ routerset_needs_geoip(const routerset_t *set) return set && smartlist_len(set->country_names); } -#if 0 /** Return true iff there are no entries in set. */ static int routerset_is_empty(const routerset_t *set) { return !set || smartlist_len(set->list) == 0; } -#endif /** Helper. Return true iff set contains a router based on the other * provided fields. Return higher values for more specific subentries: a @@ -5659,10 +5657,15 @@ routerset_to_string(const routerset_t *set) int routerset_equal(const routerset_t *old, const routerset_t *new) { - if (old == NULL && new == NULL) + if (routerset_is_empty(old) && routerset_is_empty(new)) { + /* Two empty sets are equal */ return 1; - else if (old == NULL || new == NULL) + } else if (routerset_is_empty(old) || routerset_is_empty(new)) { + /* An empty set is equal to nothing else. */ return 0; + } + tor_assert(old != NULL); + tor_assert(new != NULL); if (smartlist_len(old->list) != smartlist_len(new->list)) return 0;

1 0

[tor/master] When cannibalizing a circuit, make sure it has no ExcludeNodes on it
by nickm＠torproject.org 27 Apr '11

27 Apr '11

commit 6afad6b691d577fba2fe88f2fe9ed76a2f80002d Author: Nick Mathewson <nickm(a)torproject.org> Date: Sun Apr 3 19:58:28 2011 -0400 When cannibalizing a circuit, make sure it has no ExcludeNodes on it This could happen if StrictNodes was 0 and we were forced to pick an excluded node as the last hop of the circuit. --- src/or/circuitlist.c | 19 ++++++++++++++----- 1 files changed, 14 insertions(+), 5 deletions(-) diff --git a/src/or/circuitlist.c b/src/or/circuitlist.c index 42073fb..ce324ca 100644 --- a/src/or/circuitlist.c +++ b/src/or/circuitlist.c @@ -923,6 +923,7 @@ circuit_find_to_cannibalize(uint8_t purpose, extend_info_t *info, int need_uptime = (flags & CIRCLAUNCH_NEED_UPTIME) != 0; int need_capacity = (flags & CIRCLAUNCH_NEED_CAPACITY) != 0; int internal = (flags & CIRCLAUNCH_IS_INTERNAL) != 0; + or_options_t *options = get_options(); /* Make sure we're not trying to create a onehop circ by * cannibalization. */ @@ -933,11 +934,6 @@ circuit_find_to_cannibalize(uint8_t purpose, extend_info_t *info, "capacity %d, internal %d", purpose, need_uptime, need_capacity, internal); - /* XXX022-1090 We should make sure that when we cannibalize a circuit, it - * contains no excluded nodes. (This is possible if StrictNodes is 0, and - * we thought we needed to use an excluded exit node for, say, a directory - * operation.) -NM */ - for (_circ=global_circuitlist; _circ; _circ = _circ->next) { if (CIRCUIT_IS_ORIGIN(_circ) && _circ->state == CIRCUIT_STATE_OPEN && @@ -966,6 +962,19 @@ circuit_find_to_cannibalize(uint8_t purpose, extend_info_t *info, hop=hop->next; } while (hop!=circ->cpath); } + if (options->ExcludeNodes) { + /* Make sure no existing nodes in the circuit are excluded for + * general use. (This may be possible if StrictNodes is 0, and we + * thought we needed to use an otherwise excluded node for, say, a + * directory operation.) */ + crypt_path_t *hop = circ->cpath; + do { + if (routerset_contains_extendinfo(options->ExcludeNodes, + hop->extend_info)) + goto next; + hop = hop->next; + } while (hop != circ->cpath); + } if (!best || (best->build_state->need_uptime && !need_uptime)) best = circ; next: ;

1 0

[tor/master] When there is a transition in permitted nodes, apply it to trackexithosts map
by nickm＠torproject.org 27 Apr '11

27 Apr '11

commit 80adb3de507db4cd67208396e1ea301f131c1228 Author: Nick Mathewson <nickm(a)torproject.org> Date: Sun Apr 3 19:43:47 2011 -0400 When there is a transition in permitted nodes, apply it to trackexithosts map IOW, if we were using TrackExitHosts, and we added an excluded node or removed a node from exitnodes, we wouldn't actually remove the mapping that points us at the new node. Also, note with an XXX022 comment a place that I think we are looking at the wrong string. --- src/or/config.c | 1 + src/or/connection_edge.c | 54 +++++++++++++++++++++++++++++++++++++++++++-- src/or/connection_edge.h | 1 + src/or/routerlist.c | 2 +- src/or/routerlist.h | 1 + 5 files changed, 55 insertions(+), 4 deletions(-) diff --git a/src/or/config.c b/src/or/config.c index 44cde85..f003e4d 100644 --- a/src/or/config.c +++ b/src/or/config.c @@ -1271,6 +1271,7 @@ options_act(or_options_t *old_options) "excluded node lists. Abandoning previous circuits."); circuit_mark_all_unused_circs(); circuit_expire_all_dirty_circs(); + addressmap_clear_excluded_trackexithosts(options); } /* How long should we delay counting bridge stats after becoming a bridge? diff --git a/src/or/connection_edge.c b/src/or/connection_edge.c index f435976..5f322ca 100644 --- a/src/or/connection_edge.c +++ b/src/or/connection_edge.c @@ -789,9 +789,6 @@ addressmap_ent_remove(const char *address, addressmap_entry_t *ent) static void clear_trackexithost_mappings(const char *exitname) { - /* XXXX022-1090 We need a variant of this that clears all mappings no longer - permitted because of changes to the ExcludeNodes, ExitNodes, or - ExcludeExitNodes settings. */ char *suffix; size_t suffix_len; if (!addressmap || !exitname) @@ -802,6 +799,7 @@ clear_trackexithost_mappings(const char *exitname) tor_strlower(suffix); STRMAP_FOREACH_MODIFY(addressmap, address, addressmap_entry_t *, ent) { + /* XXXX022 HEY! Shouldn't this look at ent->new_address? */ if (ent->source == ADDRMAPSRC_TRACKEXIT && !strcmpend(address, suffix)) { addressmap_ent_remove(address, ent); MAP_DEL_CURRENT(address); @@ -811,6 +809,56 @@ clear_trackexithost_mappings(const char *exitname) tor_free(suffix); } +/** Remove all TRACKEXIT mappings from the addressmap for which the target + * host is unknown or no longer allowed. */ +void +addressmap_clear_excluded_trackexithosts(or_options_t *options) +{ + const routerset_t *allow_nodes = options->ExitNodes; + const routerset_t *exclude_nodes = options->_ExcludeExitNodesUnion; + + if (!addressmap) + return; + if (routerset_is_empty(allow_nodes)) + allow_nodes = NULL; + if (allow_nodes == NULL && routerset_is_empty(exclude_nodes)) + return; + + STRMAP_FOREACH_MODIFY(addressmap, address, addressmap_entry_t *, ent) { + size_t len; + const char *target = ent->new_address, *dot; + char *nodename; + routerinfo_t *ri; /* XXX023 Use node_t. */ + + if (strcmpend(target, ".exit")) { + /* Not a .exit mapping */ + continue; + } else if (ent->source != ADDRMAPSRC_TRACKEXIT) { + /* Not a trackexit mapping. */ + continue; + } + len = strlen(target); + if (len < 6) + continue; /* malformed. */ + dot = target + len - 6; /* dot now points to just before .exit */ + dot = strrchr(dot, '.'); /* dot now points to the . before .exit, or NULL */ + if (!dot) { + nodename = tor_strndup(target, len-5); + } else { + nodename = tor_strndup(dot+1, strlen(dot+1)-5); + } + ri = router_get_by_nickname(nodename, 0); + tor_free(nodename); + if (!ri || + (allow_nodes && !routerset_contains_router(allow_nodes, ri)) || + routerset_contains_router(exclude_nodes, ri)) { + /* We don't know this one, or we want to be rid of it. */ + addressmap_ent_remove(address, ent); + MAP_DEL_CURRENT(address); + } + } STRMAP_FOREACH_END; +} + /** Remove all entries from the addressmap that were set via the * configuration file or the command line. */ void diff --git a/src/or/connection_edge.h b/src/or/connection_edge.h index 0b08dd0..c4ae467 100644 --- a/src/or/connection_edge.h +++ b/src/or/connection_edge.h @@ -62,6 +62,7 @@ int connection_ap_process_transparent(edge_connection_t *conn); int address_is_invalid_destination(const char *address, int client); void addressmap_init(void); +void addressmap_clear_excluded_trackexithosts(or_options_t *options); void addressmap_clean(time_t now); void addressmap_clear_configured(void); void addressmap_clear_transient(void); diff --git a/src/or/routerlist.c b/src/or/routerlist.c index d5e8a6b..d9f099b 100644 --- a/src/or/routerlist.c +++ b/src/or/routerlist.c @@ -5474,7 +5474,7 @@ routerset_needs_geoip(const routerset_t *set) } /** Return true iff there are no entries in set. */ -static int +int routerset_is_empty(const routerset_t *set) { return !set || smartlist_len(set->list) == 0; diff --git a/src/or/routerlist.h b/src/or/routerlist.h index 3bbdc42..fec1870 100644 --- a/src/or/routerlist.h +++ b/src/or/routerlist.h @@ -167,6 +167,7 @@ int routerset_parse(routerset_t *target, const char *s, void routerset_union(routerset_t *target, const routerset_t *source); int routerset_is_list(const routerset_t *set); int routerset_needs_geoip(const routerset_t *set); +int routerset_is_empty(const routerset_t *set); int routerset_contains_router(const routerset_t *set, routerinfo_t *ri); int routerset_contains_routerstatus(const routerset_t *set, routerstatus_t *rs);

1 0

[tor/master] Fix a log msg
by nickm＠torproject.org 27 Apr '11

27 Apr '11

commit 8e2904e269e039713c2b2e7be10b82e11f239cd0 Author: Sebastian Hahn <sebastian(a)torproject.org> Date: Fri Apr 8 04:03:50 2011 +0200 Fix a log msg --- src/or/router.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/src/or/router.c b/src/or/router.c index 64cb079..0ef4728 100644 --- a/src/or/router.c +++ b/src/or/router.c @@ -865,7 +865,7 @@ consider_testing_reachability(int test_or, int test_dir) if ((msg = rate_limit_log(&warning_limit, approx_time()))) { log_warn(LD_CIRC, "Can't peform self-tests for this relay: we have " "listed ourself in ExcludeNodes, and StrictNodes is set. " - "We will cannot learn whether we are usable, and will not " + "We cannot learn whether we are usable, and will not " "be able to advertise ourself.%s", msg); tor_free(msg); }

1 0

[tor/master] Explain the "using anyway" log message better
by nickm＠torproject.org 27 Apr '11

27 Apr '11

commit 92ec36a061de17dd4e378d5ce34d82f91eee9f86 Author: Sebastian Hahn <sebastian(a)torproject.org> Date: Fri Apr 8 04:01:23 2011 +0200 Explain the "using anyway" log message better Also add a request to report any cases where we are not honoring StrictNodes to the developers: These should now all be bugs. --- src/or/circuitbuild.c | 18 ++++++++++++------ 1 files changed, 12 insertions(+), 6 deletions(-) diff --git a/src/or/circuitbuild.c b/src/or/circuitbuild.c index c58509f..681f524 100644 --- a/src/or/circuitbuild.c +++ b/src/or/circuitbuild.c @@ -2896,7 +2896,7 @@ warn_if_last_router_excluded(origin_circuit_t *circ, const extend_info_t *exit) case CIRCUIT_PURPOSE_C_GENERAL: if (circ->build_state->is_internal) return; - description = "Requested exit node"; + description = "requested exit node"; rs = options->_ExcludeExitNodesUnion; break; case CIRCUIT_PURPOSE_C_INTRODUCING: @@ -2911,22 +2911,28 @@ warn_if_last_router_excluded(origin_circuit_t *circ, const extend_info_t *exit) case CIRCUIT_PURPOSE_C_REND_READY: case CIRCUIT_PURPOSE_C_REND_READY_INTRO_ACKED: case CIRCUIT_PURPOSE_C_REND_JOINED: - description = "Chosen rendezvous point"; + description = "chosen rendezvous point"; domain = LD_BUG; break; case CIRCUIT_PURPOSE_CONTROLLER: rs = options->_ExcludeExitNodesUnion; - description = "Controller-selected circuit target"; + description = "controller-selected circuit target"; break; } if (routerset_contains_extendinfo(rs, exit)) { - log_fn(LOG_WARN, domain, "%s '%s' is in ExcludeNodes%s. Using anyway " - "(circuit purpose %d).", + /* We should never get here if StrictNodes is set to 1. */ + if (options->StrictNodes) + log_warn(LD_BUG, "Using an excluded node with StrictNodes set. " + "Please report the following log message to the " + "developers."); + log_fn(LOG_WARN, domain, "Using %s '%s' which is listed in " + "ExcludeNodes%s, because no other options were available. To " + "prevent this, set the StrictNodes configuration option." + "(Circuit purpose is %d)", description,exit->nickname, rs==options->ExcludeNodes?"":" or ExcludeExitNodes", (int)purpose); - /* XXX022-1090 "using anyway" is freaking people out -RD */ circuit_log_path(LOG_WARN, domain, circ); }

1 0

[tor/master] Add a big changelog entry for bug 1090 fixes
by nickm＠torproject.org 27 Apr '11

27 Apr '11

commit c49f660c1a9f196c8cbb4863bb377bdb6e642539 Author: Nick Mathewson <nickm(a)torproject.org> Date: Wed Apr 27 13:33:38 2011 -0400 Add a big changelog entry for bug 1090 fixes --- changes/bug1090-general | 73 +++++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 73 insertions(+), 0 deletions(-) diff --git a/changes/bug1090-general b/changes/bug1090-general new file mode 100644 index 0000000..4656315 --- /dev/null +++ b/changes/bug1090-general @@ -0,0 +1,73 @@ + o Major features and bugfixes (node selection) + + - Revise and unify the meaning of the ExitNodes, EntryNodes, + ExcludeEntryNodes, ExcludeExitNodes, ExcludeNodes, and + StrictNodes options. Previously, we had been ambiguous in + describing what counted as an "exit" node, and what operations + exactly "StrictNodes 0" would permit. This created confusion + when people saw nodes built through unexpected circuits, and + made it hard to tell real bugs from surprises. We now stipulate + that the intended behavior is: + + . "Exit", in the context of ExitNodes and ExcludeExitNodes, + means a node that delivers user traffic outside the Tor + network. + . "Entry", in the context of EntryNodes and ExcludeEntryNodes, + means a node used as the first hop of a multihop circuit: + it doesn't include direct connections to directory servers. + . "ExcludeNodes" applies to all nodes. + . "StrictNodes" changes the behavior of ExcludeNodes only. + When StrictNodes is set, Tor should avoid all nodes listed + in ExcludeNodes, even when it will make user requests + fail. When StrictNodes is *not* set, then Tor should + follow ExcludeNodes whenever it can, except when it must + use an excluded node to perform self-tests, connect to a + hidden service, provide a hidden service, fulfill a .exit + request, upload directory information, or fetch directory + information. + + Collectively, the changes to implement the behavior are a fix for + bug 1090. + + - ExcludeNodes now takes precedence over EntryNodes and ExitNodes: + if a node is listed in both, it's treated as excluded. + + - ExcludeNodes now applies to directory nodes: as a preference if + StrictNodes is 0, or an absolute requirement if StrictNodes is 1. + (Don't exclude all the directory authorities and set StrictNodes + to 1 unless you really want your Tor to break.) + + - ExcludeNodes and ExcludeExitNodes now override exit enclaving. + + - ExcludeExitNodes now overrides .exit requests. + + - We don't use bridges from ExcludeNodes. + + - When StrictNodes is 1: + . We now apply ExcludeNodes to hidden service introduction points + and to rendezvous points selected by hidden service users. + This can make your hidden service less reliable: use it with + caution! + . If we have used ExcludeNodes on ourself, do not try self-tests. + . If we have excluded all the directory authorities, we will + not even try to upload our descriptor if we're a server. + . Do not honor .exit requests to an excluded node. + + - Remove a misfeature that caused us to ignore the Fast/Stable flags + if ExitNodes was set. Bugfix on 0.2.2.7-alpha. + + - When the set of permitted nodes changes, we now remove any + mappings introduced via TrackExitHosts to now-excluded nodes. + Bugfix on 0.1.0.1-rc. + + - We never cannibalize a circuit that had excluded nodes on it, + even if StrictNodes is 0. Bugfix on 0.1.0.1-rc. + + - Improve log messages related to excluded nodes. + + - Revert a change where we would be laxer about attaching streams to + circuits than when building the circuits. This was meant to + prevent a set of bugs where streams were never attachable, but our + improved code here should make this unnecessary. Bugfix on + 0.2.2.7-alpha. +

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[tor/master] Check transition of circuit purpose from INTRO->GENERAL if nodes are constrained
by nickm＠torproject.org 27 Apr '11

27 Apr '11

commit 79a3b3cd3719b3b87b0edbab62b256e42c7b42de Author: Nick Mathewson <nickm(a)torproject.org> Date: Sun Apr 3 20:06:31 2011 -0400 Check transition of circuit purpose from INTRO->GENERAL if nodes are constrained This looked at first like another fun way around our node selection logic: if we had introduction circuits, and we wound up building too many, we would turn extras into general-purpose circuits. But when we did so, we wouldn't necessarily check whether the general-purpose circuits conformed to our node constraints. For example, the last node could totally be in ExcludedExitNodes and we wouldn't have cared... ...except that the circuit should already be internal, so it won't get user streams attached to it, so the transition should generally be allowed. Add an assert to make sure we're right about this, and have it not check whether ExitNodes is set, since that's irrelevant to internal circuits. --- src/or/rendservice.c | 29 +++++++++++++++++++---------- 1 files changed, 19 insertions(+), 10 deletions(-) diff --git a/src/or/rendservice.c b/src/or/rendservice.c index 5b85394..cd8f9ea 100644 --- a/src/or/rendservice.c +++ b/src/or/rendservice.c @@ -1347,17 +1347,26 @@ rend_service_intro_has_opened(origin_circuit_t *circuit) } /* If we already have enough introduction circuits for this service, - * redefine this one as a general circuit. */ + * redefine this one as a general circuit or close it, depending. */ if (count_established_intro_points(serviceid) > NUM_INTRO_POINTS) { - log_info(LD_CIRC|LD_REND, "We have just finished an introduction " - "circuit, but we already have enough. Redefining purpose to " - "general."); - /* XXX022-1090: This can wind up violating ExcludeNodes/ - * ExitNodes/ExcludeExitNodes restrictions. - */ - TO_CIRCUIT(circuit)->purpose = CIRCUIT_PURPOSE_C_GENERAL; - circuit_has_opened(circuit); - return; + or_options_t *options = get_options(); + if (options->ExcludeNodes) { + /* XXXX in some future version, we can test whether the transition is + allowed or not given the actual nodes in the circuit. But for now, + this case, we might as well close the thing. */ + log_info(LD_CIRC|LD_REND, "We have just finished an introduction " + "circuit, but we already have enough. Closing it."); + circuit_mark_for_close(TO_CIRCUIT(circuit), END_CIRC_REASON_NONE); + return; + } else { + tor_assert(circuit->build_state->is_internal); + log_info(LD_CIRC|LD_REND, "We have just finished an introduction " + "circuit, but we already have enough. Redefining purpose to " + "general; leaving as internal."); + TO_CIRCUIT(circuit)->purpose = CIRCUIT_PURPOSE_C_GENERAL; + circuit_has_opened(circuit); + return; + } } log_info(LD_REND,

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