commit 90f6071d8dc0c23c0a2e7713ae1bba5ef44d09c2 Author: Nick Mathewson <nickm@torproject.org> Date: Mon Sep 10 18:13:28 2012 -0400 New FallbackDir option to add extra directories for bootstraping This replaces the old FallbackConsensus notion, and should provide a way -- assuming we pick reasonable nodes! -- to give clients suggestions of placs to go to get their first consensus. --- changes/fallback_dirsource | 9 +++ doc/tor.1.txt | 5 ++ src/or/config.c | 136 ++++++++++++++++++++++++++++++++++++++++---- src/or/or.h | 4 + src/or/router.c | 2 +- src/or/routerlist.c | 15 +++-- src/or/routerlist.h | 4 +- 7 files changed, 155 insertions(+), 20 deletions(-) diff --git a/changes/fallback_dirsource b/changes/fallback_dirsource new file mode 100644 index 0000000..61db81b --- /dev/null +++ b/changes/fallback_dirsource @@ -0,0 +1,9 @@ + o Major features: + - Add a new FallbackDir option to use when we can't use a directory + from the consensus (either because we lack a consensus, or because + they're all down). Currently, all authorities are fallbacks by + default, and there are no other default fallbacks, but that will + change. This option will allow us to give clients a longer list + of servers to try to get a consensus from when first connecting + to the Tor network, and thereby reduce load on the directory + authorities. diff --git a/doc/tor.1.txt b/doc/tor.1.txt index 112af81..2633899 100644 --- a/doc/tor.1.txt +++ b/doc/tor.1.txt @@ -292,6 +292,11 @@ GENERAL OPTIONS **DataDirectory** __DIR__:: Store working data in DIR (Default: @LOCALSTATEDIR@/lib/tor) +**FallbackDir** __address__:__port__ orport=__port__ id=__fingerprint__:: + When we're unable to connect to any directory cache for directory info + (usually because we don't know about any yet) we try a FallbackDir. + By default, the directory authorities are also FallbackDirs. + **DirAuthority** [__nickname__] [**flags**] __address__:__port__ __fingerprint__:: Use a nonstandard authoritative directory server at the provided address and port, with the specified key fingerprint. This option can be repeated diff --git a/src/or/config.c b/src/or/config.c index a4ccf07..63c8d48 100644 --- a/src/or/config.c +++ b/src/or/config.c @@ -228,6 +228,7 @@ static config_var_t option_vars_[] = { V(ExitPortStatistics, BOOL, "0"), V(ExtendAllowPrivateAddresses, BOOL, "0"), V(ExtraInfoStatistics, BOOL, "1"), + V(FallbackDir, LINELIST, NULL), #if defined (WINCE) V(FallbackNetworkstatusFile, FILENAME, "fallback-consensus"), @@ -474,6 +475,8 @@ static char *get_bindaddr_from_transport_listen_line(const char *line, static int parse_dir_authority_line(const char *line, dirinfo_type_t required_type, int validate_only); +static int parse_dir_fallback_line(const char *line, + int validate_only); static void port_cfg_free(port_cfg_t *port); static int parse_ports(or_options_t *options, int validate_only, char **msg_out, int *n_ports_out); @@ -756,7 +759,7 @@ static void add_default_trusted_dir_authorities(dirinfo_type_t type) { int i; - const char *dirservers[] = { + const char *authorities[] = { "moria1 orport=9101 no-v2 " "v3ident=D586D18309DED4CD6D57C18FDB97EFA96D330566 " "128.31.0.39:9131 9695 DFC3 5FFE B861 329B 9F1A B04C 4639 7020 CE31", @@ -785,10 +788,27 @@ add_default_trusted_dir_authorities(dirinfo_type_t type) "154.35.32.5:80 CF6D 0AAF B385 BE71 B8E1 11FC 5CFF 4B47 9237 33BC", NULL }; - for (i=0; dirservers[i]; i++) { - if (parse_dir_authority_line(dirservers[i], type, 0)<0) { - log_err(LD_BUG, "Couldn't parse internal dirserver line %s", - dirservers[i]); + for (i=0; authorities[i]; i++) { + if (parse_dir_authority_line(authorities[i], type, 0)<0) { + log_err(LD_BUG, "Couldn't parse internal DirAuthority line %s", + authorities[i]); + } + } +} + +/** Add the default fallback directory servers into the fallback directory + * server list. */ +static void +add_default_fallback_dir_servers(void) +{ + int i; + const char *fallback[] = { + NULL + }; + for (i=0; fallback[i]; i++) { + if (parse_dir_fallback_line(fallback[i], 0)<0) { + log_err(LD_BUG, "Couldn't parse internal FallbackDir line %s", + fallback[i]); } } } @@ -798,7 +818,7 @@ add_default_trusted_dir_authorities(dirinfo_type_t type) * user if we changed any dangerous ones. */ static int -validate_dir_authorities(or_options_t *options, or_options_t *old_options) +validate_dir_servers(or_options_t *options, or_options_t *old_options) { config_line_t *cl; @@ -842,6 +862,9 @@ validate_dir_authorities(or_options_t *options, or_options_t *old_options) for (cl = options->AlternateHSAuthority; cl; cl = cl->next) if (parse_dir_authority_line(cl->value, NO_DIRINFO, 1)<0) return -1; + for (cl = options->FallbackDir; cl; cl = cl->next) + if (parse_dir_fallback_line(cl->value, 1)<0) + return -1; return 0; } @@ -849,14 +872,15 @@ validate_dir_authorities(or_options_t *options, or_options_t *old_options) * as appropriate. */ static int -consider_adding_dir_authorities(const or_options_t *options, - const or_options_t *old_options) +consider_adding_dir_servers(const or_options_t *options, + const or_options_t *old_options) { config_line_t *cl; int need_to_update = !smartlist_len(router_get_trusted_dir_servers()) || !smartlist_len(router_get_fallback_dir_servers()) || !old_options || !config_lines_eq(options->DirAuthorities, old_options->DirAuthorities) || + !config_lines_eq(options->FallbackDir, old_options->FallbackDir) || !config_lines_eq(options->AlternateBridgeAuthority, old_options->AlternateBridgeAuthority) || !config_lines_eq(options->AlternateDirAuthority, @@ -882,6 +906,8 @@ consider_adding_dir_authorities(const or_options_t *options, type |= HIDSERV_DIRINFO; add_default_trusted_dir_authorities(type); } + if (!options->FallbackDir) + add_default_fallback_dir_servers(); for (cl = options->DirAuthorities; cl; cl = cl->next) if (parse_dir_authority_line(cl->value, NO_DIRINFO, 0)<0) @@ -895,6 +921,9 @@ consider_adding_dir_authorities(const or_options_t *options, for (cl = options->AlternateHSAuthority; cl; cl = cl->next) if (parse_dir_authority_line(cl->value, NO_DIRINFO, 0)<0) return -1; + for (cl = options->FallbackDir; cl; cl = cl->next) + if (parse_dir_fallback_line(cl->value, 0)<0) + return -1; return 0; } @@ -1217,7 +1246,7 @@ options_act(const or_options_t *old_options) return -1; } - if (consider_adding_dir_authorities(options, old_options) < 0) + if (consider_adding_dir_servers(options, old_options) < 0) return -1; #ifdef NON_ANONYMOUS_MODE_ENABLED @@ -2844,8 +2873,9 @@ options_validate(or_options_t *old_options, or_options_t *options, if (validate_addr_policies(options, msg) < 0) return -1; - if (validate_dir_authorities(options, old_options) < 0) - REJECT("Directory authority line did not parse. See logs for details."); + if (validate_dir_servers(options, old_options) < 0) + REJECT("Directory authority/fallback line did not parse. See logs " + "for details."); if (options->UseBridges && !options->Bridges) REJECT("If you set UseBridges, you must specify at least one bridge."); @@ -4439,7 +4469,7 @@ parse_dir_authority_line(const char *line, dirinfo_type_t required_type, log_debug(LD_DIR, "Trusted %d dirserver at %s:%d (%s)", (int)type, address, (int)dir_port, (char*)smartlist_get(items,0)); if (!(ds = trusted_dir_server_new(nickname, address, dir_port, or_port, - digest, v3_digest, type))) + digest, v3_digest, type, 1.0))) goto err; dir_server_add(ds); } @@ -4460,6 +4490,88 @@ parse_dir_authority_line(const char *line, dirinfo_type_t required_type, return r; } +/** Read the contents of a FallbackDir line from <b>line</b>. If + * <b>validate_only</b> is 0, and the line is well-formed, then add the + * dirserver described in the line as a fallback directory. Return 0 on + * success, or -1 if the line isn't well-formed or if we can't add it. */ +static int +parse_dir_fallback_line(const char *line, + int validate_only) +{ + int r = -1; + smartlist_t *items = smartlist_new(), *positional = smartlist_new(); + int orport = -1; + uint16_t dirport; + tor_addr_t addr; + int ok; + char id[DIGEST_LEN]; + char *address=NULL; + + memset(id, 0, sizeof(id)); + smartlist_split_string(items, line, NULL, + SPLIT_SKIP_SPACE|SPLIT_IGNORE_BLANK, -1); + SMARTLIST_FOREACH_BEGIN(items, const char *, cp) { + const char *eq = strchr(cp, '='); + ok = 1; + if (! eq) { + smartlist_add(positional, (char*)cp); + continue; + } + if (!strcmpstart(cp, "orport=")) + orport = (int)tor_parse_long(cp+strlen("orport="), 10, + 1, 65535, &ok, NULL); + else if (!strcmpstart(cp, "id=")) + ok = !base16_decode(id, DIGEST_LEN, + cp+strlen("id="), strlen(cp)-strlen("id=")); + if (!ok) { + log_warn(LD_CONFIG, "Bad FallbackDir option %s", escaped(cp)); + goto end; + } + } SMARTLIST_FOREACH_END(cp); + + if (smartlist_len(positional) != 1) { + log_warn(LD_CONFIG, "Couldn't parse FallbackDir line %s", escaped(line)); + goto end; + } + + if (tor_digest_is_zero(id)) { + log_warn(LD_CONFIG, "Missing identity on FallbackDir line"); + goto end; + } + + if (orport <= 0) { + log_warn(LD_CONFIG, "Missing orport on FallbackDir line"); + goto end; + } + + if (tor_addr_port_split(LOG_INFO, smartlist_get(positional, 0), + &address, &dirport) < 0 || + tor_addr_parse(&addr, address)<0) { + log_warn(LD_CONFIG, "Couldn't parse address:port %s on FallbackDir line", + (const char*)smartlist_get(positional, 0)); + goto end; + } + + if (!validate_only) { + dir_server_t *ds; + ds = fallback_dir_server_new(&addr, dirport, orport, id, 1.0); + if (!ds) { + log_warn(LD_CONFIG, "Couldn't create FallbackDir %s", escaped(line)); + goto end; + } + dir_server_add(ds); + } + + r = 0; + + end: + SMARTLIST_FOREACH(items, char *, cp, tor_free(cp)); + smartlist_free(items); + smartlist_free(positional); + tor_free(address); + return r; +} + /** Free all storage held in <b>port</b> */ static void port_cfg_free(port_cfg_t *port) diff --git a/src/or/or.h b/src/or/or.h index 70490a6..70e0007 100644 --- a/src/or/or.h +++ b/src/or/or.h @@ -3428,6 +3428,9 @@ typedef struct { * use the "Alternate*Authority" options below instead. */ config_line_t *DirAuthorities; + /** List of fallback directory servers */ + config_line_t *FallbackDir; + /** If set, use these main (currently v3) directory authorities and * not the default ones. */ config_line_t *AlternateDirAuthority; @@ -4496,6 +4499,7 @@ typedef struct dir_server_t { uint32_t addr; /**< IPv4 address. */ uint16_t dir_port; /**< Directory port. */ uint16_t or_port; /**< OR port: Used for tunneling connections. */ + double weight; /** Weight used when selecting this node at random */ char digest[DIGEST_LEN]; /**< Digest of identity key. */ char v3_identity_digest[DIGEST_LEN]; /**< Digest of v3 (authority only, * high-security) identity key. */ diff --git a/src/or/router.c b/src/or/router.c index 34eb66a..5786103 100644 --- a/src/or/router.c +++ b/src/or/router.c @@ -737,7 +737,7 @@ init_keys(void) router_get_advertised_or_port(options), digest, v3_digest, - type); + type, 0.0); if (!ds) { log_err(LD_GENERAL,"We want to be a directory authority, but we " "couldn't add ourselves to the authority list. Failing."); diff --git a/src/or/routerlist.c b/src/or/routerlist.c index ac4e46d..e6e7413 100644 --- a/src/or/routerlist.c +++ b/src/or/routerlist.c @@ -3785,12 +3785,16 @@ dir_server_new(int is_authority, const char *hostname, uint16_t dir_port, uint16_t or_port, const char *digest, const char *v3_auth_digest, - dirinfo_type_t type) + dirinfo_type_t type, + double weight) { dir_server_t *ent; uint32_t a; char *hostname_ = NULL; + if (weight < 0) + return NULL; + if (tor_addr_family(addr) == AF_INET) a = tor_addr_to_ipv4h(addr); else @@ -3810,6 +3814,7 @@ dir_server_new(int is_authority, ent->is_running = 1; ent->is_authority = is_authority; ent->type = type; + ent->weight = weight; memcpy(ent->digest, digest, DIGEST_LEN); if (v3_auth_digest && (type & V3_DIRINFO)) memcpy(ent->v3_identity_digest, v3_auth_digest, DIGEST_LEN); @@ -3842,7 +3847,7 @@ dir_server_t * trusted_dir_server_new(const char *nickname, const char *address, uint16_t dir_port, uint16_t or_port, const char *digest, const char *v3_auth_digest, - dirinfo_type_t type) + dirinfo_type_t type, double weight) { uint32_t a; tor_addr_t addr; @@ -3869,7 +3874,7 @@ trusted_dir_server_new(const char *nickname, const char *address, result = dir_server_new(1, nickname, &addr, hostname, dir_port, or_port, digest, - v3_auth_digest, type); + v3_auth_digest, type, weight); tor_free(hostname); return result; } @@ -3880,10 +3885,10 @@ trusted_dir_server_new(const char *nickname, const char *address, dir_server_t * fallback_dir_server_new(const tor_addr_t *addr, uint16_t dir_port, uint16_t or_port, - const char *id_digest) + const char *id_digest, double weight) { return dir_server_new(0, NULL, addr, NULL, dir_port, or_port, id_digest, - NULL, ALL_DIRINFO); + NULL, ALL_DIRINFO, weight); } /** Add a directory server to the global list(s). */ diff --git a/src/or/routerlist.h b/src/or/routerlist.h index 1d527d0..81ba1ac 100644 --- a/src/or/routerlist.h +++ b/src/or/routerlist.h @@ -136,10 +136,10 @@ int router_exit_policy_rejects_all(const routerinfo_t *router); dir_server_t *trusted_dir_server_new(const char *nickname, const char *address, uint16_t dir_port, uint16_t or_port, const char *digest, const char *v3_auth_digest, - dirinfo_type_t type); + dirinfo_type_t type, double weight); dir_server_t *fallback_dir_server_new(const tor_addr_t *addr, uint16_t dir_port, uint16_t or_port, - const char *id_digest); + const char *id_digest, double weight); void dir_server_add(dir_server_t *ent); void authority_cert_free(authority_cert_t *cert);