tor-commits November 2012

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1508 discussions

[tor/master] Record, send, and receive flags in BEGIN cells
by nickm＠torproject.org 15 Nov '12

15 Nov '12

commit c64ee7099f32c2630d8ed65febf92357cd5e9487 Author: Nick Mathewson <nickm(a)torproject.org> Date: Wed Oct 24 23:39:28 2012 -0400 Record, send, and receive flags in BEGIN cells --- src/or/connection_edge.c | 8 ++++++-- src/or/or.h | 2 ++ 2 files changed, 8 insertions(+), 2 deletions(-) diff --git a/src/or/connection_edge.c b/src/or/connection_edge.c index a840b43..9a4f274 100644 --- a/src/or/connection_edge.c +++ b/src/or/connection_edge.c @@ -1656,6 +1656,10 @@ connection_ap_handshake_send_begin(entry_connection_t *ap_conn) ap_conn->socks_request->address : "", ap_conn->socks_request->port); payload_len = (int)strlen(payload)+1; + if (payload_len <= RELAY_PAYLOAD_SIZE - 4) { + set_uint32(payload + payload_len, htonl(edge_conn->begincell_flags)); + payload_len += 4; + } log_info(LD_APP, "Sending relay cell %d to begin stream %d.", @@ -2235,14 +2239,14 @@ connection_exit_begin_conn(cell_t *cell, circuit_t *circ) } log_debug(LD_EXIT,"Creating new exit connection."); - n_stream = edge_connection_new(CONN_TYPE_EXIT, AF_INET); + n_stream = edge_connection_new(CONN_TYPE_EXIT, AF_INET);/*XXXX IPv6*/ /* Remember the tunneled request ID in the new edge connection, so that * we can measure download times. */ n_stream->dirreq_id = circ->dirreq_id; n_stream->base_.purpose = EXIT_PURPOSE_CONNECT; - + n_stream->begincell_flags = bcell.flags; n_stream->stream_id = rh.stream_id; n_stream->base_.port = port; /* leave n_stream->s at -1, because it's not yet valid */ diff --git a/src/or/or.h b/src/or/or.h index 05d27b1..fa90aae 100644 --- a/src/or/or.h +++ b/src/or/or.h @@ -1414,6 +1414,8 @@ typedef struct edge_connection_t { uint32_t address_ttl; /**< TTL for address-to-addr mapping on exit * connection. Exit connections only. */ + uint32_t begincell_flags; /** Flags sent or received in the BEGIN cell + * for this connection */ streamid_t stream_id; /**< The stream ID used for this edge connection on its * circuit */

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[tor/master] Add IPv6 support to compare_to_addr_to_node_policy
by nickm＠torproject.org 15 Nov '12

15 Nov '12

commit b35a0d113233fa29439500555201b85c1dec64b1 Author: Nick Mathewson <nickm(a)torproject.org> Date: Wed Oct 24 23:05:44 2012 -0400 Add IPv6 support to compare_to_addr_to_node_policy --- src/or/policies.c | 19 ++++++++++++++++--- src/or/router.c | 19 +++++++++++++++++++ 2 files changed, 35 insertions(+), 3 deletions(-) diff --git a/src/or/policies.c b/src/or/policies.c index 8367446..16b3e4f 100644 --- a/src/or/policies.c +++ b/src/or/policies.c @@ -1616,16 +1616,29 @@ compare_tor_addr_to_node_policy(const tor_addr_t *addr, uint16_t port, if (node->rejects_all) return ADDR_POLICY_REJECTED; - if (node->ri) + if (addr && tor_addr_family(addr) == AF_INET6) { + const short_policy_t *p = NULL; + if (node->ri) + p = node->ri->ipv6_exit_policy; + else if (node->md) + p = node->md->ipv6_exit_policy; + if (p) + return compare_tor_addr_to_short_policy(addr, port, p); + else + return ADDR_POLICY_REJECTED; + } + + if (node->ri) { return compare_tor_addr_to_addr_policy(addr, port, node->ri->exit_policy); - else if (node->md) { + } else if (node->md) { if (node->md->exit_policy == NULL) return ADDR_POLICY_REJECTED; else return compare_tor_addr_to_short_policy(addr, port, node->md->exit_policy); - } else + } else { return ADDR_POLICY_PROBABLY_REJECTED; + } } /** Implementation for GETINFO control command: knows the answer for questions diff --git a/src/or/router.c b/src/or/router.c index efe24d7..cdd33bb 100644 --- a/src/or/router.c +++ b/src/or/router.c @@ -1609,6 +1609,11 @@ router_rebuild_descriptor(int force) } ri->policy_is_reject_star = policy_is_reject_star(ri->exit_policy); +#if 0 + /* XXXX024 Don't actually enable this code until exiting to an IPv6 + * address works. */ + ri->ipv6_exit_policy = policy_summarize(&ri->exit_policy, AF_INET6); +#endif #if 0 /* XXXX NM NM I belive this is safe to remove */ @@ -2150,6 +2155,20 @@ router_dump_router_to_string(char *s, size_t maxlen, routerinfo_t *router, } } + if (router->ipv6_exit_policy) { + char *p6 = write_short_policy(router->ipv6_exit_policy); + if (p6 && strcmp(p6, "reject 1-65535")) { + result = tor_snprintf(s+written, maxlen-written, + "ipv6-policy %s\n", p6); + if (result<0) { + log_warn(LD_BUG,"Descriptor printf of policy ran out of room"); + return -1; + } + written += result; + } + tor_free(p6); + } + if (written + DIROBJ_MAX_SIG_LEN > maxlen) { /* Not enough room for signature. */ log_warn(LD_BUG,"not enough room left in descriptor for signature!");

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[tor/master] Simplest version of server-side IPv6 support (no dns)
by nickm＠torproject.org 15 Nov '12

15 Nov '12

commit c3faa0ebd55f7de80db1a3aa5e64a79c72708722 Author: Nick Mathewson <nickm(a)torproject.org> Date: Wed Oct 24 23:45:24 2012 -0400 Simplest version of server-side IPv6 support (no dns) This is a relatively simple set of changes: we mostly need to remove a few "but not for IPv6" changes. We also needed to tweak the handling of DNS code to generate RESOLVED cells that could get an IPv6 answer in return. --- src/or/connection_edge.c | 3 +++ src/or/dns.c | 38 +++++++++++++++++++++++++++++++------- src/or/router.c | 4 ++-- 3 files changed, 36 insertions(+), 9 deletions(-) diff --git a/src/or/connection_edge.c b/src/or/connection_edge.c index 9a4f274..d97bea7 100644 --- a/src/or/connection_edge.c +++ b/src/or/connection_edge.c @@ -2408,6 +2408,9 @@ connection_exit_connect(edge_connection_t *edge_conn) addr = &conn->addr; port = conn->port; + if (tor_addr_family(addr) == AF_INET6) + conn->socket_family = AF_INET6; + log_debug(LD_EXIT,"about to try connecting"); switch (connection_connect(conn, conn->address, addr, port, &socket_error)) { case -1: { diff --git a/src/or/dns.c b/src/or/dns.c index 5e1d0b4..d26314a 100644 --- a/src/or/dns.c +++ b/src/or/dns.c @@ -160,7 +160,8 @@ typedef struct cached_resolve_t { static void purge_expired_resolves(time_t now); static void dns_found_answer(const char *address, uint8_t is_reverse, - uint32_t addr, const char *hostname, char outcome, + uint32_t addr, + const char *hostname, char outcome, uint32_t ttl); static void send_resolved_cell(edge_connection_t *conn, uint8_t answer_type); static int launch_resolve(edge_connection_t *exitconn); @@ -490,9 +491,13 @@ purge_expired_resolves(time_t now) assert_cache_ok(); } +/* argument for send_resolved_cell only, meaning "let the answer type be ipv4 + * or ipv6 depending on the connection's address". */ +#define RESOLVED_TYPE_AUTO 0xff + /** Send a response to the RESOLVE request of a connection. * answer_type must be one of - * RESOLVED_TYPE_(IPV4|ERROR|ERROR_TRANSIENT). + * RESOLVED_TYPE_(IPV4|IPV6|ERROR|ERROR_TRANSIENT|AUTO). * * If circ is provided, and we have a cached answer, send the * answer back along circ; otherwise, send the answer back along @@ -505,6 +510,16 @@ send_resolved_cell(edge_connection_t *conn, uint8_t answer_type) size_t buflen; uint32_t ttl; + if (answer_type == RESOLVED_TYPE_AUTO) { + sa_family_t family = tor_addr_family(&conn->base_.addr); + if (family == AF_INET) + answer_type = RESOLVED_TYPE_IPV4; + else if (family == AF_INET6) + answer_type = RESOLVED_TYPE_IPV6; + else + answer_type = RESOLVED_TYPE_ERROR_TRANSIENT; + } + buf[0] = answer_type; ttl = dns_clip_ttl(conn->address_ttl); @@ -516,7 +531,15 @@ send_resolved_cell(edge_connection_t *conn, uint8_t answer_type) set_uint32(buf+6, htonl(ttl)); buflen = 10; break; - /*XXXX IP6 need ipv6 implementation */ + case RESOLVED_TYPE_IPV6: + { + const uint8_t *bytes = tor_addr_to_in6_addr8(&conn->base_.addr); + buf[1] = 16; + memcpy(buf+2, bytes, 16); + set_uint32(buf+18, htonl(ttl)); + buflen = 22; + } + break; case RESOLVED_TYPE_ERROR_TRANSIENT: case RESOLVED_TYPE_ERROR: { @@ -614,7 +637,7 @@ dns_resolve(edge_connection_t *exitconn) if (hostname) send_resolved_hostname_cell(exitconn, hostname); else - send_resolved_cell(exitconn, RESOLVED_TYPE_IPV4); + send_resolved_cell(exitconn, RESOLVED_TYPE_AUTO); exitconn->on_circuit = NULL; } else { /* Add to the n_streams list; the calling function will send back a @@ -693,12 +716,13 @@ dns_resolve_impl(edge_connection_t *exitconn, int is_resolve, /* first check if exitconn->base_.address is an IP. If so, we already * know the answer. */ if (tor_addr_parse(&addr, exitconn->base_.address) >= 0) { - if (tor_addr_family(&addr) == AF_INET) { + if (tor_addr_family(&addr) == AF_INET || + tor_addr_family(&addr) == AF_INET6) { tor_addr_copy(&exitconn->base_.addr, &addr); exitconn->address_ttl = DEFAULT_DNS_TTL; return 1; } else { - /* XXXX IPv6 */ + /* XXXX unspec? Bogus? */ return -1; } } @@ -1140,7 +1164,7 @@ dns_found_answer(const char *address, uint8_t is_reverse, uint32_t addr, if (is_reverse) send_resolved_hostname_cell(pendconn, hostname); else - send_resolved_cell(pendconn, RESOLVED_TYPE_IPV4); + send_resolved_cell(pendconn, RESOLVED_TYPE_AUTO); circ = circuit_get_by_edge_conn(pendconn); tor_assert(circ); circuit_detach_stream(circ, pendconn); diff --git a/src/or/router.c b/src/or/router.c index cdd33bb..642656f 100644 --- a/src/or/router.c +++ b/src/or/router.c @@ -1380,8 +1380,8 @@ router_compare_to_my_exit_policy(edge_connection_t *conn) if (tor_addr_is_null(&conn->base_.addr)) return -1; - /* XXXX IPv6 */ - if (tor_addr_family(&conn->base_.addr) != AF_INET) + if (tor_addr_family(&conn->base_.addr) != AF_INET && + tor_addr_family(&conn->base_.addr) != AF_INET6) return -1; return compare_tor_addr_to_addr_policy(&conn->base_.addr, conn->base_.port,

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[tor/master] Authorities put p6 lines into microdescriptors.
by nickm＠torproject.org 15 Nov '12

15 Nov '12

commit 04ea55014182776871841279f6917d1a03c4e905 Author: Nick Mathewson <nickm(a)torproject.org> Date: Wed Oct 24 22:34:55 2012 -0400 Authorities put p6 lines into microdescriptors. --- src/or/dirvote.c | 11 +++++++++++ src/or/dirvote.h | 5 ++++- 2 files changed, 15 insertions(+), 1 deletions(-) diff --git a/src/or/dirvote.c b/src/or/dirvote.c index f8b8d37..9810c82 100644 --- a/src/or/dirvote.c +++ b/src/or/dirvote.c @@ -3569,6 +3569,17 @@ dirvote_create_microdescriptor(const routerinfo_t *ri, int consensus_method) if (summary && strcmp(summary, "reject 1-65535")) smartlist_add_asprintf(chunks, "p %s\n", summary); + if (consensus_method >= MIN_METHOD_FOR_P6_LINES && + ri->ipv6_exit_policy) { + /* XXXX024 This doesn't match proposal 208, which says these should + * be taken unchanged from the routerinfo. That's bogosity, IMO: + * the proposal should have said to do this instead.*/ + char *p6 = write_short_policy(ri->ipv6_exit_policy); + if (p6 && strcmp(p6, "reject 1-65535")) + smartlist_add_asprintf(chunks, "p6 %s\n", p6); + tor_free(p6); + } + output = smartlist_join_strings(chunks, "", 0, NULL); { diff --git a/src/or/dirvote.h b/src/or/dirvote.h index 04cf2f9..d14a375 100644 --- a/src/or/dirvote.h +++ b/src/or/dirvote.h @@ -20,7 +20,7 @@ #define MIN_VOTE_INTERVAL 300 /** The highest consensus method that we currently support. */ -#define MAX_SUPPORTED_CONSENSUS_METHOD 14 +#define MAX_SUPPORTED_CONSENSUS_METHOD 15 /** Lowest consensus method that contains a 'directory-footer' marker */ #define MIN_METHOD_FOR_FOOTER 9 @@ -45,6 +45,9 @@ /** Lowest consensus method that contains "a" lines. */ #define MIN_METHOD_FOR_A_LINES 14 +/** Lowest consensus method where microdescs may include a "p6" line. */ +#define MIN_METHOD_FOR_P6_LINES 15 + void dirvote_free_all(void); /* vote manipulation */

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[tor/master] Add an IPv6Exit configuration option
by nickm＠torproject.org 15 Nov '12

15 Nov '12

commit 9016d9e8294a35295851d12b62de4ac9a5549709 Author: Nick Mathewson <nickm(a)torproject.org> Date: Thu Oct 25 00:20:41 2012 -0400 Add an IPv6Exit configuration option Don't advertise an IPv6 exit policy, or accept IPv6 exit requests, if IPv6Exit is not true. --- src/or/config.c | 3 ++- src/or/connection_edge.c | 17 +++++++++++++++-- src/or/connection_edge.h | 5 +++++ src/or/or.h | 2 ++ src/or/policies.c | 5 +++++ src/or/policies.h | 1 + src/or/router.c | 1 + src/test/test.c | 6 +++--- 8 files changed, 34 insertions(+), 6 deletions(-) diff --git a/src/or/config.c b/src/or/config.c index f8ac67e..76038d5 100644 --- a/src/or/config.c +++ b/src/or/config.c @@ -276,7 +276,7 @@ static config_var_t option_vars_[] = { V(HTTPProxyAuthenticator, STRING, NULL), V(HTTPSProxy, STRING, NULL), V(HTTPSProxyAuthenticator, STRING, NULL), - // V(IPv6EXit, BOOL, "0"), + V(IPv6Exit, BOOL, "0"), VAR("ServerTransportPlugin", LINELIST, ServerTransportPlugin, NULL), V(Socks4Proxy, STRING, NULL), V(Socks5Proxy, STRING, NULL), @@ -3170,6 +3170,7 @@ options_transition_affects_descriptor(const or_options_t *old_options, !config_lines_eq(old_options->ExitPolicy,new_options->ExitPolicy) || old_options->ExitPolicyRejectPrivate != new_options->ExitPolicyRejectPrivate || + old_options->IPv6Exit != new_options->IPv6Exit || !config_lines_eq(old_options->ORPort_lines, new_options->ORPort_lines) || !config_lines_eq(old_options->DirPort_lines, diff --git a/src/or/connection_edge.c b/src/or/connection_edge.c index d97bea7..373edf7 100644 --- a/src/or/connection_edge.c +++ b/src/or/connection_edge.c @@ -2238,6 +2238,17 @@ connection_exit_begin_conn(cell_t *cell, circuit_t *circ) return 0; } + if (! options->IPv6Exit) { + /* I don't care if you prefer IPv6; I can't give you any. */ + bcell.flags &= ~BEGIN_FLAG_IPV6_PREFERRED; + /* If you don't want IPv4, I can't help. */ + if (bcell.flags & BEGIN_FLAG_IPV4_NOT_OK) { + tor_free(address); + relay_send_end_cell_from_edge(rh.stream_id, circ, + END_STREAM_REASON_EXITPOLICY, NULL); + } + } + log_debug(LD_EXIT,"Creating new exit connection."); n_stream = edge_connection_new(CONN_TYPE_EXIT, AF_INET);/*XXXX IPv6*/ @@ -2395,8 +2406,10 @@ connection_exit_connect(edge_connection_t *edge_conn) connection_t *conn = TO_CONN(edge_conn); int socket_error = 0; - if (!connection_edge_is_rendezvous_stream(edge_conn) && - router_compare_to_my_exit_policy(edge_conn)) { + if ( (!connection_edge_is_rendezvous_stream(edge_conn) && + router_compare_to_my_exit_policy(edge_conn)) || + (tor_addr_family(&conn->addr) == AF_INET6 && + ! get_options()->IPv6Exit)) { log_info(LD_EXIT,"%s:%d failed exit policy. Closing.", escaped_safe_str_client(conn->address), conn->port); connection_edge_end(edge_conn, END_STREAM_REASON_EXITPOLICY); diff --git a/src/or/connection_edge.h b/src/or/connection_edge.h index f3d1038..39f492d 100644 --- a/src/or/connection_edge.h +++ b/src/or/connection_edge.h @@ -92,6 +92,11 @@ int connection_edge_update_circuit_isolation(const entry_connection_t *conn, void circuit_clear_isolation(origin_circuit_t *circ); #ifdef CONNECTION_EDGE_PRIVATE + +#define BEGIN_FLAG_IPV6_OK (1u<<0) +#define BEGIN_FLAG_IPV4_NOT_OK (1u<<1) +#define BEGIN_FLAG_IPV6_PREFERRED (1u<<2) + /*DOCDOC*/ typedef struct begin_cell_t { char *address; diff --git a/src/or/or.h b/src/or/or.h index fa90aae..9d22e11 100644 --- a/src/or/or.h +++ b/src/or/or.h @@ -3745,6 +3745,8 @@ typedef struct { int PathBiasScaleFactor; /** @} */ + int IPv6Exit; /**< DOCDOC*/ + } or_options_t; /** Persistent state for an onion router, as saved to disk. */ diff --git a/src/or/policies.c b/src/or/policies.c index 16b3e4f..f9646f8 100644 --- a/src/or/policies.c +++ b/src/or/policies.c @@ -437,6 +437,7 @@ validate_addr_policies(const or_options_t *options, char **msg) *msg = NULL; if (policies_parse_exit_policy(options->ExitPolicy, &addr_policy, + options->IPv6Exit, options->ExitPolicyRejectPrivate, NULL, !options->BridgeRelay)) REJECT("Error in ExitPolicy entry."); @@ -938,9 +939,13 @@ exit_policy_remove_redundancies(smartlist_t *dest) */ int policies_parse_exit_policy(config_line_t *cfg, smartlist_t **dest, + int ipv6_exit, int rejectprivate, const char *local_address, int add_default_policy) { + if (!ipv6_exit) { + append_exit_policy_string(dest, "reject *6:*"); + } if (rejectprivate) { append_exit_policy_string(dest, "reject private:*"); if (local_address) { diff --git a/src/or/policies.h b/src/or/policies.h index e9d214d..f8de911 100644 --- a/src/or/policies.h +++ b/src/or/policies.h @@ -43,6 +43,7 @@ addr_policy_result_t compare_tor_addr_to_node_policy(const tor_addr_t *addr, uint16_t port, const node_t *node); int policies_parse_exit_policy(config_line_t *cfg, smartlist_t **dest, + int ipv6exit, int rejectprivate, const char *local_address, int add_default_policy); void policies_exit_policy_append_reject_star(smartlist_t **dest); diff --git a/src/or/router.c b/src/or/router.c index 642656f..5e9f3d5 100644 --- a/src/or/router.c +++ b/src/or/router.c @@ -1604,6 +1604,7 @@ router_rebuild_descriptor(int force) policies_exit_policy_append_reject_star(&ri->exit_policy); } else { policies_parse_exit_policy(options->ExitPolicy, &ri->exit_policy, + options->IPv6Exit, options->ExitPolicyRejectPrivate, ri->address, !options->BridgeRelay); } diff --git a/src/test/test.c b/src/test/test.c index 6652e77..d70f255 100644 --- a/src/test/test.c +++ b/src/test/test.c @@ -1044,7 +1044,7 @@ test_policy_summary_helper(const char *policy_str, line.value = (char *)policy_str; line.next = NULL; - r = policies_parse_exit_policy(&line, &policy, 0, NULL, 1); + r = policies_parse_exit_policy(&line, &policy, 1, 0, NULL, 1); test_eq(r, 0); summary = policy_summarize(policy, AF_INET); @@ -1101,7 +1101,7 @@ test_policies(void) test_assert(ADDR_POLICY_REJECTED == compare_tor_addr_to_addr_policy(&tar, 2, policy)); - test_assert(0 == policies_parse_exit_policy(NULL, &policy2, 1, NULL, 1)); + test_assert(0 == policies_parse_exit_policy(NULL, &policy2, 1, 1, NULL, 1)); test_assert(policy2); policy3 = smartlist_new(); @@ -1188,7 +1188,7 @@ test_policies(void) line.key = (char*)"foo"; line.value = (char*)"accept *:80,reject private:*,reject *:*"; line.next = NULL; - test_assert(0 == policies_parse_exit_policy(&line, &policy, 0, NULL, 1)); + test_assert(0 == policies_parse_exit_policy(&line, &policy, 1, 0, NULL, 1)); test_assert(policy); //test_streq(policy->string, "accept *:80"); //test_streq(policy->next->string, "reject *:*");

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[tor/master] Refactor begin cell parsing into its own function, with tests.
by nickm＠torproject.org 15 Nov '12

15 Nov '12

commit 462ebb270a10f02573b1847649db45b94c0e0fc3 Author: Nick Mathewson <nickm(a)torproject.org> Date: Mon Oct 22 11:28:37 2012 -0400 Refactor begin cell parsing into its own function, with tests. Add 'flags' argument to begin cells, per proposal 208. --- src/or/connection_edge.c | 105 ++++++++++++++----- src/or/connection_edge.h | 15 +++ src/test/include.am | 1 + src/test/test.c | 2 + src/test/test_cell_formats.c | 234 ++++++++++++++++++++++++++++++++++++++++++ 5 files changed, 330 insertions(+), 27 deletions(-) diff --git a/src/or/connection_edge.c b/src/or/connection_edge.c index f548576..a840b43 100644 --- a/src/or/connection_edge.c +++ b/src/or/connection_edge.c @@ -8,6 +8,7 @@ * \file connection_edge.c * \brief Handle edge streams. **/ +#define CONNECTION_EDGE_PRIVATE #include "or.h" #include "addressmap.h" @@ -2059,6 +2060,64 @@ connection_ap_handshake_socks_reply(entry_connection_t *conn, char *reply, return; } +/* DOCDOC */ +/* static */ int +begin_cell_parse(const cell_t *cell, begin_cell_t *bcell, + uint8_t *end_reason_out) +{ + relay_header_t rh; + const uint8_t *body, *nul; + + memset(bcell, 0, sizeof(*bcell)); + *end_reason_out = END_STREAM_REASON_MISC; + + relay_header_unpack(&rh, cell->payload); + if (rh.length > RELAY_PAYLOAD_SIZE) { + return -2; /*XXXX why not TORPROTOL? */ + } + + bcell->stream_id = rh.stream_id; + + if (rh.command == RELAY_COMMAND_BEGIN_DIR) { + bcell->is_begindir = 1; + return 0; + } else if (rh.command != RELAY_COMMAND_BEGIN) { + log_warn(LD_BUG, "Got an unexpected command %d", (int)rh.command); + *end_reason_out = END_STREAM_REASON_INTERNAL; + return -1; + } + + body = cell->payload + RELAY_HEADER_SIZE; + nul = memchr(body, 0, rh.length); + if (! nul) { + log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, + "Relay begin cell has no \\0. Closing."); + *end_reason_out = END_STREAM_REASON_TORPROTOCOL; + return -1; + } + + if (tor_addr_port_split(LOG_PROTOCOL_WARN, + (char*)(body), + &bcell->address,&bcell->port)<0) { + log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, + "Unable to parse addr:port in relay begin cell. Closing."); + *end_reason_out = END_STREAM_REASON_TORPROTOCOL; + return -1; + } + if (bcell->port == 0) { + log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, + "Missing port in relay begin cell. Closing."); + tor_free(bcell->address); + *end_reason_out = END_STREAM_REASON_TORPROTOCOL; + return -1; + } + if (body + rh.length >= nul + 4) + bcell->flags = ntohl(get_uint32(nul+1)); + + return 0; +} + + /** A relay 'begin' or 'begin_dir' cell has arrived, and either we are * an exit hop for the circuit, or we are the origin and it is a * rendezvous begin. @@ -2082,10 +2141,13 @@ connection_exit_begin_conn(cell_t *cell, circuit_t *circ) { edge_connection_t *n_stream; relay_header_t rh; - char *address=NULL; - uint16_t port; + char *address = NULL; + uint16_t port = 0; or_circuit_t *or_circ = NULL; const or_options_t *options = get_options(); + begin_cell_t bcell; + int r; + uint8_t end_reason=0; assert_circuit_ok(circ); if (!CIRCUIT_IS_ORIGIN(circ)) @@ -2109,31 +2171,20 @@ connection_exit_begin_conn(cell_t *cell, circuit_t *circ) return 0; } - if (rh.command == RELAY_COMMAND_BEGIN) { - if (!memchr(cell->payload+RELAY_HEADER_SIZE, 0, rh.length)) { - log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, - "Relay begin cell has no \\0. Closing."); - relay_send_end_cell_from_edge(rh.stream_id, circ, - END_STREAM_REASON_TORPROTOCOL, NULL); - return 0; - } - if (tor_addr_port_split(LOG_PROTOCOL_WARN, - (char*)(cell->payload+RELAY_HEADER_SIZE), - &address,&port)<0) { - log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, - "Unable to parse addr:port in relay begin cell. Closing."); - relay_send_end_cell_from_edge(rh.stream_id, circ, - END_STREAM_REASON_TORPROTOCOL, NULL); - return 0; - } - if (port==0) { - log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, - "Missing port in relay begin cell. Closing."); - relay_send_end_cell_from_edge(rh.stream_id, circ, - END_STREAM_REASON_TORPROTOCOL, NULL); - tor_free(address); - return 0; - } + r = begin_cell_parse(cell, &bcell, &end_reason); + if (r < -1) { + return -1; + } else if (r == -1) { + tor_free(bcell.address); + relay_send_end_cell_from_edge(rh.stream_id, circ, end_reason, NULL); + return 0; + } + + if (! bcell.is_begindir) { + /* Steal reference */ + address = bcell.address; + port = bcell.port; + if (or_circ && or_circ->p_chan) { if (!options->AllowSingleHopExits && (or_circ->is_first_hop || diff --git a/src/or/connection_edge.h b/src/or/connection_edge.h index b5938b3..f3d1038 100644 --- a/src/or/connection_edge.h +++ b/src/or/connection_edge.h @@ -91,5 +91,20 @@ int connection_edge_update_circuit_isolation(const entry_connection_t *conn, int dry_run); void circuit_clear_isolation(origin_circuit_t *circ); +#ifdef CONNECTION_EDGE_PRIVATE +/*DOCDOC*/ +typedef struct begin_cell_t { + char *address; + uint32_t flags; + uint16_t port; + uint16_t stream_id; + unsigned is_begindir : 1; +} begin_cell_t; + +int begin_cell_parse(const cell_t *cell, begin_cell_t *bcell, + uint8_t *end_reason_out); +#endif + + #endif diff --git a/src/test/include.am b/src/test/include.am index bdfe498..075df36 100644 --- a/src/test/include.am +++ b/src/test/include.am @@ -14,6 +14,7 @@ src_test_AM_CPPFLAGS = -DSHARE_DATADIR="\"$(datadir)\"" \ src_test_test_SOURCES = \ src/test/test.c \ src/test/test_addr.c \ + src/test/test_cell_formats.c \ src/test/test_containers.c \ src/test/test_crypto.c \ src/test/test_data.c \ diff --git a/src/test/test.c b/src/test/test.c index 1eaa65c..fc3c36e 100644 --- a/src/test/test.c +++ b/src/test/test.c @@ -1983,6 +1983,7 @@ extern struct testcase_t pt_tests[]; extern struct testcase_t config_tests[]; extern struct testcase_t introduce_tests[]; extern struct testcase_t replaycache_tests[]; +extern struct testcase_t cell_format_tests[]; static struct testgroup_t testgroups[] = { { "", test_array }, @@ -1991,6 +1992,7 @@ static struct testgroup_t testgroups[] = { { "crypto/", crypto_tests }, { "container/", container_tests }, { "util/", util_tests }, + { "cellfmt/", cell_format_tests }, { "dir/", dir_tests }, { "dir/md/", microdesc_tests }, { "pt/", pt_tests }, diff --git a/src/test/test_cell_formats.c b/src/test/test_cell_formats.c new file mode 100644 index 0000000..2199a05 --- /dev/null +++ b/src/test/test_cell_formats.c @@ -0,0 +1,234 @@ +/* Copyright (c) 2001-2004, Roger Dingledine. + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2012, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +#include "orconfig.h" + +#define CONNECTION_EDGE_PRIVATE +#include "or.h" +#include "connection_edge.h" +#include "relay.h" +#include "test.h" + +#include <stdlib.h> +#include <string.h> + +static void +test_cfmt_relay_header(void *arg) +{ + relay_header_t rh; + const uint8_t hdr_1[RELAY_HEADER_SIZE] = + "\x03" "\x00\x00" "\x21\x22" "ABCD" "\x01\x03"; + uint8_t hdr_out[RELAY_HEADER_SIZE]; + (void)arg; + + tt_int_op(sizeof(hdr_1), ==, RELAY_HEADER_SIZE); + relay_header_unpack(&rh, hdr_1); + tt_int_op(rh.command, ==, 3); + tt_int_op(rh.recognized, ==, 0); + tt_int_op(rh.stream_id, ==, 0x2122); + test_mem_op(rh.integrity, ==, "ABCD", 4); + tt_int_op(rh.length, ==, 0x103); + + relay_header_pack(hdr_out, &rh); + test_mem_op(hdr_out, ==, hdr_1, RELAY_HEADER_SIZE); + + done: + ; +} + +static void +make_relay_cell(cell_t *out, uint8_t command, + const void *body, size_t bodylen) +{ + relay_header_t rh; + + memset(&rh, 0, sizeof(rh)); + rh.stream_id = 5; + rh.command = command; + rh.length = bodylen; + + out->command = CELL_RELAY; + out->circ_id = 10; + relay_header_pack(out->payload, &rh); + + memcpy(out->payload + RELAY_HEADER_SIZE, body, bodylen); +} + +static void +test_cfmt_begin_cells(void *arg) +{ + cell_t cell; + begin_cell_t bcell; + uint8_t end_reason; + (void)arg; + + /* Try begindir. */ + memset(&bcell, 0x7f, sizeof(bcell)); + make_relay_cell(&cell, RELAY_COMMAND_BEGIN_DIR, "", 0); + tt_int_op(0, ==, begin_cell_parse(&cell, &bcell, &end_reason)); + tt_ptr_op(NULL, ==, bcell.address); + tt_int_op(0, ==, bcell.flags); + tt_int_op(0, ==, bcell.port); + tt_int_op(5, ==, bcell.stream_id); + tt_int_op(1, ==, bcell.is_begindir); + + /* A Begindir with extra stuff. */ + memset(&bcell, 0x7f, sizeof(bcell)); + make_relay_cell(&cell, RELAY_COMMAND_BEGIN_DIR, "12345", 5); + tt_int_op(0, ==, begin_cell_parse(&cell, &bcell, &end_reason)); + tt_ptr_op(NULL, ==, bcell.address); + tt_int_op(0, ==, bcell.flags); + tt_int_op(0, ==, bcell.port); + tt_int_op(5, ==, bcell.stream_id); + tt_int_op(1, ==, bcell.is_begindir); + + /* A short but valid begin cell */ + memset(&bcell, 0x7f, sizeof(bcell)); + make_relay_cell(&cell, RELAY_COMMAND_BEGIN, "a.b:9", 6); + tt_int_op(0, ==, begin_cell_parse(&cell, &bcell, &end_reason)); + tt_str_op("a.b", ==, bcell.address); + tt_int_op(0, ==, bcell.flags); + tt_int_op(9, ==, bcell.port); + tt_int_op(5, ==, bcell.stream_id); + tt_int_op(0, ==, bcell.is_begindir); + tor_free(bcell.address); + + /* A significantly loner begin cell */ + memset(&bcell, 0x7f, sizeof(bcell)); + { + const char c[] = "here-is-a-nice-long.hostname.com:65535"; + make_relay_cell(&cell, RELAY_COMMAND_BEGIN, c, strlen(c)+1); + } + tt_int_op(0, ==, begin_cell_parse(&cell, &bcell, &end_reason)); + tt_str_op("here-is-a-nice-long.hostname.com", ==, bcell.address); + tt_int_op(0, ==, bcell.flags); + tt_int_op(65535, ==, bcell.port); + tt_int_op(5, ==, bcell.stream_id); + tt_int_op(0, ==, bcell.is_begindir); + tor_free(bcell.address); + + /* An IPv4 begin cell. */ + memset(&bcell, 0x7f, sizeof(bcell)); + make_relay_cell(&cell, RELAY_COMMAND_BEGIN, "18.9.22.169:80", 15); + tt_int_op(0, ==, begin_cell_parse(&cell, &bcell, &end_reason)); + tt_str_op("18.9.22.169", ==, bcell.address); + tt_int_op(0, ==, bcell.flags); + tt_int_op(80, ==, bcell.port); + tt_int_op(5, ==, bcell.stream_id); + tt_int_op(0, ==, bcell.is_begindir); + tor_free(bcell.address); + + /* An IPv6 begin cell. Let's make sure we handle colons*/ + memset(&bcell, 0x7f, sizeof(bcell)); + make_relay_cell(&cell, RELAY_COMMAND_BEGIN, + "[2620::6b0:b:1a1a:0:26e5:480e]:80", 34); + tt_int_op(0, ==, begin_cell_parse(&cell, &bcell, &end_reason)); + tt_str_op("[2620::6b0:b:1a1a:0:26e5:480e]", ==, bcell.address); + tt_int_op(0, ==, bcell.flags); + tt_int_op(80, ==, bcell.port); + tt_int_op(5, ==, bcell.stream_id); + tt_int_op(0, ==, bcell.is_begindir); + tor_free(bcell.address); + + /* a begin cell with extra junk but not enough for flags. */ + memset(&bcell, 0x7f, sizeof(bcell)); + { + const char c[] = "another.example.com:80\x00\x01\x02"; + make_relay_cell(&cell, RELAY_COMMAND_BEGIN, c, sizeof(c)-1); + } + tt_int_op(0, ==, begin_cell_parse(&cell, &bcell, &end_reason)); + tt_str_op("another.example.com", ==, bcell.address); + tt_int_op(0, ==, bcell.flags); + tt_int_op(80, ==, bcell.port); + tt_int_op(5, ==, bcell.stream_id); + tt_int_op(0, ==, bcell.is_begindir); + tor_free(bcell.address); + + /* a begin cell with flags. */ + memset(&bcell, 0x7f, sizeof(bcell)); + { + const char c[] = "another.example.com:443\x00\x01\x02\x03\x04"; + make_relay_cell(&cell, RELAY_COMMAND_BEGIN, c, sizeof(c)-1); + } + tt_int_op(0, ==, begin_cell_parse(&cell, &bcell, &end_reason)); + tt_str_op("another.example.com", ==, bcell.address); + tt_int_op(0x1020304, ==, bcell.flags); + tt_int_op(443, ==, bcell.port); + tt_int_op(5, ==, bcell.stream_id); + tt_int_op(0, ==, bcell.is_begindir); + tor_free(bcell.address); + + /* a begin cell with flags and even more cruft after that. */ + memset(&bcell, 0x7f, sizeof(bcell)); + { + const char c[] = "a-further.example.com:22\x00\xee\xaa\x00\xffHi mom"; + make_relay_cell(&cell, RELAY_COMMAND_BEGIN, c, sizeof(c)-1); + } + tt_int_op(0, ==, begin_cell_parse(&cell, &bcell, &end_reason)); + tt_str_op("a-further.example.com", ==, bcell.address); + tt_int_op(0xeeaa00ff, ==, bcell.flags); + tt_int_op(22, ==, bcell.port); + tt_int_op(5, ==, bcell.stream_id); + tt_int_op(0, ==, bcell.is_begindir); + tor_free(bcell.address); + + /* bad begin cell: impossible length. */ + memset(&bcell, 0x7f, sizeof(bcell)); + make_relay_cell(&cell, RELAY_COMMAND_BEGIN, "a.b:80", 7); + cell.payload[9] = 0x01; /* Set length to 510 */ + cell.payload[10] = 0xfe; + { + relay_header_t rh; + relay_header_unpack(&rh, cell.payload); + tt_int_op(rh.length, ==, 510); + } + tt_int_op(-2, ==, begin_cell_parse(&cell, &bcell, &end_reason)); + + /* Bad begin cell: no body. */ + memset(&bcell, 0x7f, sizeof(bcell)); + make_relay_cell(&cell, RELAY_COMMAND_BEGIN, "", 0); + tt_int_op(-1, ==, begin_cell_parse(&cell, &bcell, &end_reason)); + + /* bad begin cell: no body. */ + memset(&bcell, 0x7f, sizeof(bcell)); + make_relay_cell(&cell, RELAY_COMMAND_BEGIN, "", 0); + tt_int_op(-1, ==, begin_cell_parse(&cell, &bcell, &end_reason)); + + /* bad begin cell: no colon */ + memset(&bcell, 0x7f, sizeof(bcell)); + make_relay_cell(&cell, RELAY_COMMAND_BEGIN, "a.b", 4); + tt_int_op(-1, ==, begin_cell_parse(&cell, &bcell, &end_reason)); + + /* bad begin cell: no ports */ + memset(&bcell, 0x7f, sizeof(bcell)); + make_relay_cell(&cell, RELAY_COMMAND_BEGIN, "a.b:", 5); + tt_int_op(-1, ==, begin_cell_parse(&cell, &bcell, &end_reason)); + + /* bad begin cell: bad port */ + memset(&bcell, 0x7f, sizeof(bcell)); + make_relay_cell(&cell, RELAY_COMMAND_BEGIN, "a.b:xyz", 8); + tt_int_op(-1, ==, begin_cell_parse(&cell, &bcell, &end_reason)); + memset(&bcell, 0x7f, sizeof(bcell)); + make_relay_cell(&cell, RELAY_COMMAND_BEGIN, "a.b:100000", 11); + tt_int_op(-1, ==, begin_cell_parse(&cell, &bcell, &end_reason)); + + /* bad begin cell: no nul */ + memset(&bcell, 0x7f, sizeof(bcell)); + make_relay_cell(&cell, RELAY_COMMAND_BEGIN, "a.b:80", 6); + tt_int_op(-1, ==, begin_cell_parse(&cell, &bcell, &end_reason)); + + done: + tor_free(bcell.address); +} + +#define TEST(name, flags) \ + { #name, test_cfmt_ ## name, flags, 0, NULL } + +struct testcase_t cell_format_tests[] = { + TEST(relay_header, 0), + TEST(begin_cells, 0), + END_OF_TESTCASES +}; +

1 0

[tor/master] Make DNS callback pass IPv6 answers to dns_answer_found
by nickm＠torproject.org 15 Nov '12

15 Nov '12

commit b7843ca5544e741e74fe5f93fb49579e01b468c8 Author: Nick Mathewson <nickm(a)torproject.org> Date: Sat Oct 27 16:34:49 2012 -0400 Make DNS callback pass IPv6 answers to dns_answer_found Also, count ipv6 timeouts vs others. If we have too many ipv6 requests time out, then we could be degrading performance because of a broken DNS server that ignores AAAA requests. Other cases in which we never learn an AAAA address aren't so bad, since they don't slow A (ipv4) answers down very much. --- src/or/dns.c | 74 ++++++++++++++++++++++++++++++++++++++++++++++++++++----- src/or/dns.h | 1 + 2 files changed, 68 insertions(+), 7 deletions(-) diff --git a/src/or/dns.c b/src/or/dns.c index c590e01..3832421 100644 --- a/src/or/dns.c +++ b/src/or/dns.c @@ -1342,6 +1342,10 @@ configure_nameservers(int force) return -1; } +static uint64_t n_ipv6_requests_made = 0; +static uint64_t n_ipv6_timeouts = 0; +static int dns_is_broken_for_ipv6 = 0; + /** For eventdns: Called when we get an answer for a request we launched. * See eventdns.h for arguments; 'arg' holds the address we tried to resolve. */ @@ -1352,20 +1356,39 @@ evdns_callback(int result, char type, int count, int ttl, void *addresses, char *string_address = arg; uint8_t is_reverse = 0; int status = DNS_RESOLVE_FAILED_PERMANENT; - uint32_t addr = 0; + tor_addr_t addr; const char *hostname = NULL; int was_wildcarded = 0; + tor_addr_make_unspec(&addr); /*WRONG WRONG WRONG XXXX XXXXX IPV6 prop208*/ + + /* Keep track of whether IPv6 is working */ + if (type == DNS_IPv6_AAAA) { + if (result == DNS_ERR_TIMEOUT) { + ++n_ipv6_timeouts; + } + + if (n_ipv6_timeouts > 10 && + n_ipv6_timeouts > n_ipv6_requests_made / 2) { + if (! dns_is_broken_for_ipv6) { + log_notice(LD_EXIT, "More than half of our IPv6 requests seem to " + "have timed out. I'm going to assume I can't get AAAA " + "responses."); + dns_is_broken_for_ipv6 = 1; + } + } + } + if (result == DNS_ERR_NONE) { if (type == DNS_IPv4_A && count) { char answer_buf[INET_NTOA_BUF_LEN+1]; struct in_addr in; char *escaped_address; uint32_t *addrs = addresses; - in.s_addr = addrs[0]; - addr = ntohl(addrs[0]); + tor_addr_from_ipv4n(&addr, addrs[0]); status = DNS_RESOLVE_SUCCEEDED; - tor_inet_ntoa(&in, answer_buf, sizeof(answer_buf)); + + tor_addr_to_str(answer_buf, &addr, sizeof(answer_buf), 0); escaped_address = esc_for_log(string_address); if (answer_is_wildcarded(answer_buf)) { @@ -1382,6 +1405,29 @@ evdns_callback(int result, char type, int count, int ttl, void *addresses, escaped_safe_str(answer_buf)); } tor_free(escaped_address); + } else if (type == DNS_IPv6_AAAA && count) { + char answer_buf[TOR_ADDR_BUF_LEN]; + char *escaped_address; + struct in6_addr *addrs = addresses; + tor_addr_from_in6(&addr, &addrs[0]); + status = DNS_RESOLVE_SUCCEEDED; + tor_inet_ntop(AF_INET6, &addrs[0], answer_buf, sizeof(answer_buf)); + escaped_address = esc_for_log(string_address); + + if (answer_is_wildcarded(answer_buf)) { + log_debug(LD_EXIT, "eventdns said that %s resolves to ISP-hijacked " + "address %s; treating as a failure.", + safe_str(escaped_address), + escaped_safe_str(answer_buf)); + was_wildcarded = 1; + tor_addr_make_unspec(&addr); /* WRONG WRONG ETC XXXXXXXX */ + status = DNS_RESOLVE_FAILED_PERMANENT; + } else { + log_debug(LD_EXIT, "eventdns said that %s resolves to %s", + safe_str(escaped_address), + escaped_safe_str(answer_buf)); + } + tor_free(escaped_address); } else if (type == DNS_PTR && count) { char *escaped_address; is_reverse = 1; @@ -1666,8 +1712,8 @@ launch_test_addresses(int fd, short event, void *args) /* This situation is worse than the failure-hijacking situation. When this * happens, we're no good for DNS requests at all, and we shouldn't really * be an exit server.*/ - if (!options->ServerDNSTestAddresses) - return; + if (options->ServerDNSTestAddresses) { + tor_assert(the_evdns_base); SMARTLIST_FOREACH_BEGIN(options->ServerDNSTestAddresses, const char *, address) { @@ -1683,12 +1729,16 @@ launch_test_addresses(int fd, short event, void *args) a = tor_strdup(address); req = evdns_base_resolve_ipv6(the_evdns_base, address, DNS_QUERY_NO_SEARCH, evdns_callback, a); + ++n_ipv6_requests_made; if (!req) { log_info(LD_EXIT, "eventdns rejected test address %s", escaped_safe_str(address)); tor_free(a); } } SMARTLIST_FOREACH_END(address); + + } /*XXXX REINDENT */ + } #define N_WILDCARD_CHECKS 2 @@ -1756,6 +1806,13 @@ dns_seems_to_be_broken(void) return dns_is_completely_invalid; } +/** DOCDOC */ +int +dns_seems_to_be_broken_for_ipv6(void) +{ + return dns_is_broken_for_ipv6; +} + /** Forget what we've previously learned about our DNS servers' correctness. */ void dns_reset_correctness_checks(void) @@ -1765,6 +1822,8 @@ dns_reset_correctness_checks(void) n_wildcard_requests = 0; + n_ipv6_requests_made = n_ipv6_timeouts = 0; + if (dns_wildcard_list) { SMARTLIST_FOREACH(dns_wildcard_list, char *, cp, tor_free(cp)); smartlist_clear(dns_wildcard_list); @@ -1775,7 +1834,8 @@ dns_reset_correctness_checks(void) smartlist_clear(dns_wildcarded_test_address_list); } dns_wildcard_one_notice_given = dns_wildcard_notice_given = - dns_wildcarded_test_address_notice_given = dns_is_completely_invalid = 0; + dns_wildcarded_test_address_notice_given = dns_is_completely_invalid = + dns_is_broken_for_ipv6 = 0; } /** Return true iff we have noticed that the dotted-quad ip has been diff --git a/src/or/dns.h b/src/or/dns.h index 441a6c3..d2f6614 100644 --- a/src/or/dns.h +++ b/src/or/dns.h @@ -24,6 +24,7 @@ void dns_cancel_pending_resolve(const char *question); int dns_resolve(edge_connection_t *exitconn); void dns_launch_correctness_checks(void); int dns_seems_to_be_broken(void); +int dns_seems_to_be_broken_for_ipv6(void); void dns_reset_correctness_checks(void); void dump_dns_mem_usage(int severity);

1 0

[tor/master] Move address map into its own file.
by nickm＠torproject.org 15 Nov '12

15 Nov '12

commit 7908ab209350782646dfc112d346ea75974b9dec Author: Nick Mathewson <nickm(a)torproject.org> Date: Sun Oct 28 16:13:58 2012 -0400 Move address map into its own file. --- changes/split_addressmap | 3 + src/or/addressmap.c | 958 ++++++++++++++++++++++++++++++++++++++++++++++ src/or/addressmap.h | 42 ++ src/or/buffers.c | 1 + src/or/circuituse.c | 1 + src/or/config.c | 1 + src/or/connection_edge.c | 944 +--------------------------------------------- src/or/connection_edge.h | 24 -- src/or/control.c | 1 + src/or/include.am | 2 + src/or/main.c | 1 + src/or/relay.c | 1 + src/test/test_config.c | 1 + 13 files changed, 1013 insertions(+), 967 deletions(-) diff --git a/changes/split_addressmap b/changes/split_addressmap new file mode 100644 index 0000000..9f377c5 --- /dev/null +++ b/changes/split_addressmap @@ -0,0 +1,3 @@ + o Code simplification and refactoring: + - Move the client-side address-map/virtual-address/DNS-cache code + out of connection_edge.c into a new addressmap.c module. diff --git a/src/or/addressmap.c b/src/or/addressmap.c new file mode 100644 index 0000000..fec83a7 --- /dev/null +++ b/src/or/addressmap.c @@ -0,0 +1,958 @@ +/* Copyright (c) 2001 Matej Pfajfar. + * Copyright (c) 2001-2004, Roger Dingledine. + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2012, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +#include "or.h" +#include "addressmap.h" +#include "circuituse.h" +#include "config.h" +#include "connection_edge.h" +#include "control.h" +#include "dns.h" +#include "routerset.h" +#include "nodelist.h" + +/** A client-side struct to remember requests to rewrite addresses + * to new addresses. These structs are stored in the hash table + * "addressmap" below. + * + * There are 5 ways to set an address mapping: + * - A MapAddress command from the controller [permanent] + * - An AddressMap directive in the torrc [permanent] + * - When a TrackHostExits torrc directive is triggered [temporary] + * - When a DNS resolve succeeds [temporary] + * - When a DNS resolve fails [temporary] + * + * When an addressmap request is made but one is already registered, + * the new one is replaced only if the currently registered one has + * no "new_address" (that is, it's in the process of DNS resolve), + * or if the new one is permanent (expires==0 or 1). + * + * (We overload the 'expires' field, using "0" for mappings set via + * the configuration file, "1" for mappings set from the control + * interface, and other values for DNS and TrackHostExit mappings that can + * expire.) + * + * A mapping may be 'wildcarded'. If "src_wildcard" is true, then + * any address that ends with a . followed by the key for this entry will + * get remapped by it. If "dst_wildcard" is also true, then only the + * matching suffix of such addresses will get replaced by new_address. + */ +typedef struct { + char *new_address; + time_t expires; + addressmap_entry_source_t source:3; + unsigned src_wildcard:1; + unsigned dst_wildcard:1; + short num_resolve_failures; +} addressmap_entry_t; + +/** Entry for mapping addresses to which virtual address we mapped them to. */ +typedef struct { + char *ipv4_address; + char *hostname_address; +} virtaddress_entry_t; + +/** A hash table to store client-side address rewrite instructions. */ +static strmap_t *addressmap=NULL; +/** + * Table mapping addresses to which virtual address, if any, we + * assigned them to. + * + * We maintain the following invariant: if [A,B] is in + * virtaddress_reversemap, then B must be a virtual address, and [A,B] + * must be in addressmap. We do not require that the converse hold: + * if it fails, then we could end up mapping two virtual addresses to + * the same address, which is no disaster. + **/ +static strmap_t *virtaddress_reversemap=NULL; + +/** Initialize addressmap. */ +void +addressmap_init(void) +{ + addressmap = strmap_new(); + virtaddress_reversemap = strmap_new(); +} + +/** Free the memory associated with the addressmap entry _ent. */ +static void +addressmap_ent_free(void *_ent) +{ + addressmap_entry_t *ent; + if (!_ent) + return; + + ent = _ent; + tor_free(ent->new_address); + tor_free(ent); +} + +/** Free storage held by a virtaddress_entry_t* entry in ent. */ +static void +addressmap_virtaddress_ent_free(void *_ent) +{ + virtaddress_entry_t *ent; + if (!_ent) + return; + + ent = _ent; + tor_free(ent->ipv4_address); + tor_free(ent->hostname_address); + tor_free(ent); +} + +/** Free storage held by a virtaddress_entry_t* entry in ent. */ +static void +addressmap_virtaddress_remove(const char *address, addressmap_entry_t *ent) +{ + if (ent && ent->new_address && + address_is_in_virtual_range(ent->new_address)) { + virtaddress_entry_t *ve = + strmap_get(virtaddress_reversemap, ent->new_address); + /*log_fn(LOG_NOTICE,"remove reverse mapping for %s",ent->new_address);*/ + if (ve) { + if (!strcmp(address, ve->ipv4_address)) + tor_free(ve->ipv4_address); + if (!strcmp(address, ve->hostname_address)) + tor_free(ve->hostname_address); + if (!ve->ipv4_address && !ve->hostname_address) { + tor_free(ve); + strmap_remove(virtaddress_reversemap, ent->new_address); + } + } + } +} + +/** Remove ent (which must be mapped to by address) from the + * client address maps. */ +static void +addressmap_ent_remove(const char *address, addressmap_entry_t *ent) +{ + addressmap_virtaddress_remove(address, ent); + addressmap_ent_free(ent); +} + +/** Unregister all TrackHostExits mappings from any address to + * *.exitname.exit. */ +void +clear_trackexithost_mappings(const char *exitname) +{ + char *suffix = NULL; + if (!addressmap || !exitname) + return; + tor_asprintf(&suffix, ".%s.exit", exitname); + tor_strlower(suffix); + + STRMAP_FOREACH_MODIFY(addressmap, address, addressmap_entry_t *, ent) { + if (ent->source == ADDRMAPSRC_TRACKEXIT && + !strcmpend(ent->new_address, suffix)) { + addressmap_ent_remove(address, ent); + MAP_DEL_CURRENT(address); + } + } STRMAP_FOREACH_END; + + tor_free(suffix); +} + +/** Remove all TRACKEXIT mappings from the addressmap for which the target + * host is unknown or no longer allowed, or for which the source address + * is no longer in trackexithosts. */ +void +addressmap_clear_excluded_trackexithosts(const 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; + const node_t *node; + + if (!target) { + /* DNS resolving in progress */ + continue; + } else 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 */ + while (dot > target && *dot != '.') + dot--; + if (*dot == '.') dot++; + nodename = tor_strndup(dot, len-5-(dot-target));; + node = node_get_by_nickname(nodename, 0); + tor_free(nodename); + if (!node || + (allow_nodes && !routerset_contains_node(allow_nodes, node)) || + routerset_contains_node(exclude_nodes, node) || + !hostname_in_track_host_exits(options, address)) { + /* 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 AUTOMAP mappings from the addressmap for which the + * source address no longer matches AutomapHostsSuffixes, which is + * no longer allowed by AutomapHostsOnResolve, or for which the + * target address is no longer in the virtual network. */ +void +addressmap_clear_invalid_automaps(const or_options_t *options) +{ + int clear_all = !options->AutomapHostsOnResolve; + const smartlist_t *suffixes = options->AutomapHostsSuffixes; + + if (!addressmap) + return; + + if (!suffixes) + clear_all = 1; /* This should be impossible, but let's be sure. */ + + STRMAP_FOREACH_MODIFY(addressmap, src_address, addressmap_entry_t *, ent) { + int remove = clear_all; + if (ent->source != ADDRMAPSRC_AUTOMAP) + continue; /* not an automap mapping. */ + + if (!remove) { + int suffix_found = 0; + SMARTLIST_FOREACH(suffixes, const char *, suffix, { + if (!strcasecmpend(src_address, suffix)) { + suffix_found = 1; + break; + } + }); + if (!suffix_found) + remove = 1; + } + + if (!remove && ! address_is_in_virtual_range(ent->new_address)) + remove = 1; + + if (remove) { + addressmap_ent_remove(src_address, ent); + MAP_DEL_CURRENT(src_address); + } + } STRMAP_FOREACH_END; +} + +/** Remove all entries from the addressmap that were set via the + * configuration file or the command line. */ +void +addressmap_clear_configured(void) +{ + addressmap_get_mappings(NULL, 0, 0, 0); +} + +/** Remove all entries from the addressmap that are set to expire, ever. */ +void +addressmap_clear_transient(void) +{ + addressmap_get_mappings(NULL, 2, TIME_MAX, 0); +} + +/** Clean out entries from the addressmap cache that were + * added long enough ago that they are no longer valid. + */ +void +addressmap_clean(time_t now) +{ + addressmap_get_mappings(NULL, 2, now, 0); +} + +/** Free all the elements in the addressmap, and free the addressmap + * itself. */ +void +addressmap_free_all(void) +{ + strmap_free(addressmap, addressmap_ent_free); + addressmap = NULL; + + strmap_free(virtaddress_reversemap, addressmap_virtaddress_ent_free); + virtaddress_reversemap = NULL; +} + +/** Try to find a match for AddressMap expressions that use + * wildcard notation such as '*.c.d *.e.f' (so 'a.c.d' will map to 'a.e.f') or + * '*.c.d a.b.c' (so 'a.c.d' will map to a.b.c). + * Return the matching entry in AddressMap or NULL if no match is found. + * For expressions such as '*.c.d *.e.f', truncate address 'a.c.d' + * to 'a' before we return the matching AddressMap entry. + * + * This function does not handle the case where a pattern of the form "*.c.d" + * matches the address c.d -- that's done by the main addressmap_rewrite + * function. + */ +static addressmap_entry_t * +addressmap_match_superdomains(char *address) +{ + addressmap_entry_t *val; + char *cp; + + cp = address; + while ((cp = strchr(cp, '.'))) { + /* cp now points to a suffix of address that begins with a . */ + val = strmap_get_lc(addressmap, cp+1); + if (val && val->src_wildcard) { + if (val->dst_wildcard) + *cp = '\0'; + return val; + } + ++cp; + } + return NULL; +} + +/** Look at address, and rewrite it until it doesn't want any + * more rewrites; but don't get into an infinite loop. + * Don't write more than maxlen chars into address. Return true if the + * address changed; false otherwise. Set *expires_out to the + * expiry time of the result, or to time_max if the result does + * not expire. + * + * If exit_source_out is non-null, we set it as follows. If we the + * address starts out as a non-exit address, and we remap it to an .exit + * address at any point, then set *exit_source_out to the + * address_entry_source_t of the first such rule. Set *exit_source_out + * to ADDRMAPSRC_NONE if there is no such rewrite, or if the original address + * was a .exit. + */ +int +addressmap_rewrite(char *address, size_t maxlen, time_t *expires_out, + addressmap_entry_source_t *exit_source_out) +{ + addressmap_entry_t *ent; + int rewrites; + time_t expires = TIME_MAX; + addressmap_entry_source_t exit_source = ADDRMAPSRC_NONE; + char *addr_orig = tor_strdup(address); + char *log_addr_orig = NULL; + + for (rewrites = 0; rewrites < 16; rewrites++) { + int exact_match = 0; + log_addr_orig = tor_strdup(escaped_safe_str_client(address)); + + ent = strmap_get(addressmap, address); + + if (!ent || !ent->new_address) { + ent = addressmap_match_superdomains(address); + } else { + if (ent->src_wildcard && !ent->dst_wildcard && + !strcasecmp(address, ent->new_address)) { + /* This is a rule like *.example.com example.com, and we just got + * "example.com" */ + goto done; + } + + exact_match = 1; + } + + if (!ent || !ent->new_address) { + goto done; + } + + if (ent->dst_wildcard && !exact_match) { + strlcat(address, ".", maxlen); + strlcat(address, ent->new_address, maxlen); + } else { + strlcpy(address, ent->new_address, maxlen); + } + + if (!strcmpend(address, ".exit") && + strcmpend(addr_orig, ".exit") && + exit_source == ADDRMAPSRC_NONE) { + exit_source = ent->source; + } + + log_info(LD_APP, "Addressmap: rewriting %s to %s", + log_addr_orig, escaped_safe_str_client(address)); + if (ent->expires > 1 && ent->expires < expires) + expires = ent->expires; + + tor_free(log_addr_orig); + } + log_warn(LD_CONFIG, + "Loop detected: we've rewritten %s 16 times! Using it as-is.", + escaped_safe_str_client(address)); + /* it's fine to rewrite a rewrite, but don't loop forever */ + + done: + tor_free(addr_orig); + tor_free(log_addr_orig); + if (exit_source_out) + *exit_source_out = exit_source; + if (expires_out) + *expires_out = TIME_MAX; + return (rewrites > 0); +} + +/** If we have a cached reverse DNS entry for the address stored in the + * maxlen-byte buffer address (typically, a dotted quad) then + * rewrite to the cached value and return 1. Otherwise return 0. Set + * *expires_out to the expiry time of the result, or to time_max + * if the result does not expire. */ +int +addressmap_rewrite_reverse(char *address, size_t maxlen, time_t *expires_out) +{ + char *s, *cp; + addressmap_entry_t *ent; + int r = 0; + tor_asprintf(&s, "REVERSE[%s]", address); + ent = strmap_get(addressmap, s); + if (ent) { + cp = tor_strdup(escaped_safe_str_client(ent->new_address)); + log_info(LD_APP, "Rewrote reverse lookup %s -> %s", + escaped_safe_str_client(s), cp); + tor_free(cp); + strlcpy(address, ent->new_address, maxlen); + r = 1; + } + + if (expires_out) + *expires_out = (ent && ent->expires > 1) ? ent->expires : TIME_MAX; + + tor_free(s); + return r; +} + +/** Return 1 if address is already registered, else return 0. If address + * is already registered, and update_expires is non-zero, then update + * the expiry time on the mapping with update_expires if it is a + * mapping created by TrackHostExits. */ +int +addressmap_have_mapping(const char *address, int update_expiry) +{ + addressmap_entry_t *ent; + if (!(ent=strmap_get_lc(addressmap, address))) + return 0; + if (update_expiry && ent->source==ADDRMAPSRC_TRACKEXIT) + ent->expires=time(NULL) + update_expiry; + return 1; +} + +/** Register a request to map address to new_address, + * which will expire on expires (or 0 if never expires from + * config file, 1 if never expires from controller, 2 if never expires + * (virtual address mapping) from the controller.) + * + * new_address should be a newly dup'ed string, which we'll use or + * free as appropriate. We will leave address alone. + * + * If wildcard_addr is true, then the mapping will match any address + * equal to address, or any address ending with a period followed by + * address. If wildcard_addr and wildcard_new_addr are + * both true, the mapping will rewrite addresses that end with + * ".address" into ones that end with ".new_address." + * + * If new_address is NULL, or new_address is equal to + * address and wildcard_addr is equal to + * wildcard_new_addr, remove any mappings that exist from + * address. + * + * + * It is an error to set wildcard_new_addr if wildcard_addr is + * not set. */ +void +addressmap_register(const char *address, char *new_address, time_t expires, + addressmap_entry_source_t source, + const int wildcard_addr, + const int wildcard_new_addr) +{ + addressmap_entry_t *ent; + + if (wildcard_new_addr) + tor_assert(wildcard_addr); + + ent = strmap_get(addressmap, address); + if (!new_address || (!strcasecmp(address,new_address) && + wildcard_addr == wildcard_new_addr)) { + /* Remove the mapping, if any. */ + tor_free(new_address); + if (ent) { + addressmap_ent_remove(address,ent); + strmap_remove(addressmap, address); + } + return; + } + if (!ent) { /* make a new one and register it */ + ent = tor_malloc_zero(sizeof(addressmap_entry_t)); + strmap_set(addressmap, address, ent); + } else if (ent->new_address) { /* we need to clean up the old mapping. */ + if (expires > 1) { + log_info(LD_APP,"Temporary addressmap ('%s' to '%s') not performed, " + "since it's already mapped to '%s'", + safe_str_client(address), + safe_str_client(new_address), + safe_str_client(ent->new_address)); + tor_free(new_address); + return; + } + if (address_is_in_virtual_range(ent->new_address) && + expires != 2) { + /* XXX This isn't the perfect test; we want to avoid removing + * mappings set from the control interface _as virtual mapping */ + addressmap_virtaddress_remove(address, ent); + } + tor_free(ent->new_address); + } /* else { we have an in-progress resolve with no mapping. } */ + + ent->new_address = new_address; + ent->expires = expires==2 ? 1 : expires; + ent->num_resolve_failures = 0; + ent->source = source; + ent->src_wildcard = wildcard_addr ? 1 : 0; + ent->dst_wildcard = wildcard_new_addr ? 1 : 0; + + log_info(LD_CONFIG, "Addressmap: (re)mapped '%s' to '%s'", + safe_str_client(address), + safe_str_client(ent->new_address)); + control_event_address_mapped(address, ent->new_address, expires, NULL); +} + +/** An attempt to resolve address failed at some OR. + * Increment the number of resolve failures we have on record + * for it, and then return that number. + */ +int +client_dns_incr_failures(const char *address) +{ + addressmap_entry_t *ent = strmap_get(addressmap, address); + if (!ent) { + ent = tor_malloc_zero(sizeof(addressmap_entry_t)); + ent->expires = time(NULL) + MAX_DNS_ENTRY_AGE; + strmap_set(addressmap,address,ent); + } + if (ent->num_resolve_failures < SHORT_MAX) + ++ent->num_resolve_failures; /* don't overflow */ + log_info(LD_APP, "Address %s now has %d resolve failures.", + safe_str_client(address), + ent->num_resolve_failures); + return ent->num_resolve_failures; +} + +/** If address is in the client DNS addressmap, reset + * the number of resolve failures we have on record for it. + * This is used when we fail a stream because it won't resolve: + * otherwise future attempts on that address will only try once. + */ +void +client_dns_clear_failures(const char *address) +{ + addressmap_entry_t *ent = strmap_get(addressmap, address); + if (ent) + ent->num_resolve_failures = 0; +} + +/** Record the fact that address resolved to name. + * We can now use this in subsequent streams via addressmap_rewrite() + * so we can more correctly choose an exit that will allow address. + * + * If exitname is defined, then append the addresses with + * ".exitname.exit" before registering the mapping. + * + * If ttl is nonnegative, the mapping will be valid for + * ttlseconds; otherwise, we use the default. + */ +static void +client_dns_set_addressmap_impl(const char *address, const char *name, + const char *exitname, + int ttl) +{ + /* <address>.<hex or nickname>.exit\0 or just <address>\0 */ + char extendedaddress[MAX_SOCKS_ADDR_LEN+MAX_VERBOSE_NICKNAME_LEN+10]; + /* 123.123.123.123.<hex or nickname>.exit\0 or just 123.123.123.123\0 */ + char extendedval[INET_NTOA_BUF_LEN+MAX_VERBOSE_NICKNAME_LEN+10]; + + tor_assert(address); + tor_assert(name); + + if (ttl<0) + ttl = DEFAULT_DNS_TTL; + else + ttl = dns_clip_ttl(ttl); + + if (exitname) { + /* XXXX fails to ever get attempts to get an exit address of + * google.com.digest[=~]nickname.exit; we need a syntax for this that + * won't make strict RFC952-compliant applications (like us) barf. */ + tor_snprintf(extendedaddress, sizeof(extendedaddress), + "%s.%s.exit", address, exitname); + tor_snprintf(extendedval, sizeof(extendedval), + "%s.%s.exit", name, exitname); + } else { + tor_snprintf(extendedaddress, sizeof(extendedaddress), + "%s", address); + tor_snprintf(extendedval, sizeof(extendedval), + "%s", name); + } + addressmap_register(extendedaddress, tor_strdup(extendedval), + time(NULL) + ttl, ADDRMAPSRC_DNS, 0, 0); +} + +/** Record the fact that address resolved to val. + * We can now use this in subsequent streams via addressmap_rewrite() + * so we can more correctly choose an exit that will allow address. + * + * If exitname is defined, then append the addresses with + * ".exitname.exit" before registering the mapping. + * + * If ttl is nonnegative, the mapping will be valid for + * ttlseconds; otherwise, we use the default. + */ +void +client_dns_set_addressmap(const char *address, uint32_t val, + const char *exitname, + int ttl) +{ + struct in_addr in; + char valbuf[INET_NTOA_BUF_LEN]; + + tor_assert(address); + + if (tor_inet_aton(address, &in)) + return; /* If address was an IP address already, don't add a mapping. */ + in.s_addr = htonl(val); + tor_inet_ntoa(&in,valbuf,sizeof(valbuf)); + + client_dns_set_addressmap_impl(address, valbuf, exitname, ttl); +} + +/** Add a cache entry noting that address (ordinarily a dotted quad) + * resolved via a RESOLVE_PTR request to the hostname v. + * + * If exitname is defined, then append the addresses with + * ".exitname.exit" before registering the mapping. + * + * If ttl is nonnegative, the mapping will be valid for + * ttlseconds; otherwise, we use the default. + */ +void +client_dns_set_reverse_addressmap(const char *address, const char *v, + const char *exitname, + int ttl) +{ + char *s = NULL; + tor_asprintf(&s, "REVERSE[%s]", address); + client_dns_set_addressmap_impl(s, v, exitname, ttl); + tor_free(s); +} + +/* By default, we hand out 127.192.0.1 through 127.254.254.254. + * These addresses should map to localhost, so even if the + * application accidentally tried to connect to them directly (not + * via Tor), it wouldn't get too far astray. + * + * These options are configured by parse_virtual_addr_network(). + */ +/** Which network should we use for virtual IPv4 addresses? Only the first + * bits of this value are fixed. */ +static uint32_t virtual_addr_network = 0x7fc00000u; +/** How many bits of virtual_addr_network are fixed? */ +static maskbits_t virtual_addr_netmask_bits = 10; +/** What's the next virtual address we will hand out? */ +static uint32_t next_virtual_addr = 0x7fc00000u; + +/** Read a netmask of the form 127.192.0.0/10 from "val", and check whether + * it's a valid set of virtual addresses to hand out in response to MAPADDRESS + * requests. Return 0 on success; set *msg (if provided) to a newly allocated + * string and return -1 on failure. If validate_only is false, sets the + * actual virtual address range to the parsed value. */ +int +parse_virtual_addr_network(const char *val, int validate_only, + char **msg) +{ + uint32_t addr; + uint16_t port_min, port_max; + maskbits_t bits; + + if (parse_addr_and_port_range(val, &addr, &bits, &port_min, &port_max)) { + if (msg) *msg = tor_strdup("Error parsing VirtualAddressNetwork"); + return -1; + } + + if (port_min != 1 || port_max != 65535) { + if (msg) *msg = tor_strdup("Can't specify ports on VirtualAddressNetwork"); + return -1; + } + + if (bits > 16) { + if (msg) *msg = tor_strdup("VirtualAddressNetwork expects a /16 " + "network or larger"); + return -1; + } + + if (validate_only) + return 0; + + virtual_addr_network = (uint32_t)( addr & (0xfffffffful << (32-bits)) ); + virtual_addr_netmask_bits = bits; + + if (addr_mask_cmp_bits(next_virtual_addr, addr, bits)) + next_virtual_addr = addr; + + return 0; +} + +/** + * Return true iff addr is likely to have been returned by + * client_dns_get_unused_address. + **/ +int +address_is_in_virtual_range(const char *address) +{ + struct in_addr in; + tor_assert(address); + if (!strcasecmpend(address, ".virtual")) { + return 1; + } else if (tor_inet_aton(address, &in)) { + uint32_t addr = ntohl(in.s_addr); + if (!addr_mask_cmp_bits(addr, virtual_addr_network, + virtual_addr_netmask_bits)) + return 1; + } + return 0; +} + +/** Increment the value of next_virtual_addr; reset it to the start of the + * virtual address range if it wraps around. + */ +static INLINE void +increment_virtual_addr(void) +{ + ++next_virtual_addr; + if (addr_mask_cmp_bits(next_virtual_addr, virtual_addr_network, + virtual_addr_netmask_bits)) + next_virtual_addr = virtual_addr_network; +} + +/** Return a newly allocated string holding an address of type + * (one of RESOLVED_TYPE_{IPV4|HOSTNAME}) that has not yet been mapped, + * and that is very unlikely to be the address of any real host. + * + * May return NULL if we have run out of virtual addresses. + */ +static char * +addressmap_get_virtual_address(int type) +{ + char buf[64]; + tor_assert(addressmap); + + if (type == RESOLVED_TYPE_HOSTNAME) { + char rand[10]; + do { + crypto_rand(rand, sizeof(rand)); + base32_encode(buf,sizeof(buf),rand,sizeof(rand)); + strlcat(buf, ".virtual", sizeof(buf)); + } while (strmap_get(addressmap, buf)); + return tor_strdup(buf); + } else if (type == RESOLVED_TYPE_IPV4) { + // This is an imperfect estimate of how many addresses are available, but + // that's ok. + struct in_addr in; + uint32_t available = 1u << (32-virtual_addr_netmask_bits); + while (available) { + /* Don't hand out any .0 or .255 address. */ + while ((next_virtual_addr & 0xff) == 0 || + (next_virtual_addr & 0xff) == 0xff) { + increment_virtual_addr(); + if (! --available) { + log_warn(LD_CONFIG, "Ran out of virtual addresses!"); + return NULL; + } + } + in.s_addr = htonl(next_virtual_addr); + tor_inet_ntoa(&in, buf, sizeof(buf)); + if (!strmap_get(addressmap, buf)) { + increment_virtual_addr(); + break; + } + + increment_virtual_addr(); + --available; + // log_info(LD_CONFIG, "%d addrs available", (int)available); + if (! available) { + log_warn(LD_CONFIG, "Ran out of virtual addresses!"); + return NULL; + } + } + return tor_strdup(buf); + } else { + log_warn(LD_BUG, "Called with unsupported address type (%d)", type); + return NULL; + } +} + +/** A controller has requested that we map some address of type + * type to the address new_address. Choose an address + * that is unlikely to be used, and map it, and return it in a newly + * allocated string. If another address of the same type is already + * mapped to new_address, try to return a copy of that address. + * + * The string in new_address may be freed or inserted into a map + * as appropriate. May return NULL if are out of virtual addresses. + **/ +const char * +addressmap_register_virtual_address(int type, char *new_address) +{ + char **addrp; + virtaddress_entry_t *vent; + int vent_needs_to_be_added = 0; + + tor_assert(new_address); + tor_assert(addressmap); + tor_assert(virtaddress_reversemap); + + vent = strmap_get(virtaddress_reversemap, new_address); + if (!vent) { + vent = tor_malloc_zero(sizeof(virtaddress_entry_t)); + vent_needs_to_be_added = 1; + } + + addrp = (type == RESOLVED_TYPE_IPV4) ? + &vent->ipv4_address : &vent->hostname_address; + if (*addrp) { + addressmap_entry_t *ent = strmap_get(addressmap, *addrp); + if (ent && ent->new_address && + !strcasecmp(new_address, ent->new_address)) { + tor_free(new_address); + tor_assert(!vent_needs_to_be_added); + return tor_strdup(*addrp); + } else + log_warn(LD_BUG, + "Internal confusion: I thought that '%s' was mapped to by " + "'%s', but '%s' really maps to '%s'. This is a harmless bug.", + safe_str_client(new_address), + safe_str_client(*addrp), + safe_str_client(*addrp), + ent?safe_str_client(ent->new_address):"(nothing)"); + } + + tor_free(*addrp); + *addrp = addressmap_get_virtual_address(type); + if (!*addrp) { + tor_free(vent); + tor_free(new_address); + return NULL; + } + log_info(LD_APP, "Registering map from %s to %s", *addrp, new_address); + if (vent_needs_to_be_added) + strmap_set(virtaddress_reversemap, new_address, vent); + addressmap_register(*addrp, new_address, 2, ADDRMAPSRC_AUTOMAP, 0, 0); + +#if 0 + { + /* Try to catch possible bugs */ + addressmap_entry_t *ent; + ent = strmap_get(addressmap, *addrp); + tor_assert(ent); + tor_assert(!strcasecmp(ent->new_address,new_address)); + vent = strmap_get(virtaddress_reversemap, new_address); + tor_assert(vent); + tor_assert(!strcasecmp(*addrp, + (type == RESOLVED_TYPE_IPV4) ? + vent->ipv4_address : vent->hostname_address)); + log_info(LD_APP, "Map from %s to %s okay.", + safe_str_client(*addrp), + safe_str_client(new_address)); + } +#endif + + return *addrp; +} + +/** Return 1 if address has funny characters in it like colons. Return + * 0 if it's fine, or if we're configured to allow it anyway. client + * should be true if we're using this address as a client; false if we're + * using it as a server. + */ +int +address_is_invalid_destination(const char *address, int client) +{ + if (client) { + if (get_options()->AllowNonRFC953Hostnames) + return 0; + } else { + if (get_options()->ServerDNSAllowNonRFC953Hostnames) + return 0; + } + + while (*address) { + if (TOR_ISALNUM(*address) || + *address == '-' || + *address == '.' || + *address == '_') /* Underscore is not allowed, but Windows does it + * sometimes, just to thumb its nose at the IETF. */ + ++address; + else + return 1; + } + return 0; +} + +/** Iterate over all address mappings which have expiry times between + * min_expires and max_expires, inclusive. If sl is provided, add an + * "old-addr new-addr expiry" string to sl for each mapping, omitting + * the expiry time if want_expiry is false. If sl is NULL, remove the + * mappings. + */ +void +addressmap_get_mappings(smartlist_t *sl, time_t min_expires, + time_t max_expires, int want_expiry) +{ + strmap_iter_t *iter; + const char *key; + void *val_; + addressmap_entry_t *val; + + if (!addressmap) + addressmap_init(); + + for (iter = strmap_iter_init(addressmap); !strmap_iter_done(iter); ) { + strmap_iter_get(iter, &key, &val_); + val = val_; + if (val->expires >= min_expires && val->expires <= max_expires) { + if (!sl) { + iter = strmap_iter_next_rmv(addressmap,iter); + addressmap_ent_remove(key, val); + continue; + } else if (val->new_address) { + const char *src_wc = val->src_wildcard ? "*." : ""; + const char *dst_wc = val->dst_wildcard ? "*." : ""; + if (want_expiry) { + if (val->expires < 3 || val->expires == TIME_MAX) + smartlist_add_asprintf(sl, "%s%s %s%s NEVER", + src_wc, key, dst_wc, val->new_address); + else { + char time[ISO_TIME_LEN+1]; + format_iso_time(time, val->expires); + smartlist_add_asprintf(sl, "%s%s %s%s \"%s\"", + src_wc, key, dst_wc, val->new_address, + time); + } + } else { + smartlist_add_asprintf(sl, "%s%s %s%s", + src_wc, key, dst_wc, val->new_address); + } + } + } + iter = strmap_iter_next(addressmap,iter); + } +} + diff --git a/src/or/addressmap.h b/src/or/addressmap.h new file mode 100644 index 0000000..911c7ac --- /dev/null +++ b/src/or/addressmap.h @@ -0,0 +1,42 @@ +/* Copyright (c) 2001 Matej Pfajfar. + * Copyright (c) 2001-2004, Roger Dingledine. + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2012, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +#ifndef TOR_ADDRESSMAP_H +#define TOR_ADDRESSMAP_H + +void addressmap_init(void); +void addressmap_clear_excluded_trackexithosts(const or_options_t *options); +void addressmap_clear_invalid_automaps(const or_options_t *options); +void addressmap_clean(time_t now); +void addressmap_clear_configured(void); +void addressmap_clear_transient(void); +void addressmap_free_all(void); +int addressmap_rewrite(char *address, size_t maxlen, time_t *expires_out, + addressmap_entry_source_t *exit_source_out); +int addressmap_rewrite_reverse(char *address, size_t maxlen, + time_t *expires_out); +int addressmap_have_mapping(const char *address, int update_timeout); + +void addressmap_register(const char *address, char *new_address, + time_t expires, addressmap_entry_source_t source, + const int address_wildcard, + const int new_address_wildcard); +int parse_virtual_addr_network(const char *val, int validate_only, + char **msg); +int client_dns_incr_failures(const char *address); +void client_dns_clear_failures(const char *address); +void client_dns_set_addressmap(const char *address, uint32_t val, + const char *exitname, int ttl); +const char *addressmap_register_virtual_address(int type, char *new_address); +void addressmap_get_mappings(smartlist_t *sl, time_t min_expires, + time_t max_expires, int want_expiry); +int address_is_in_virtual_range(const char *addr); +void clear_trackexithost_mappings(const char *exitname); +void client_dns_set_reverse_addressmap(const char *address, const char *v, + const char *exitname, int ttl); + +#endif + diff --git a/src/or/buffers.c b/src/or/buffers.c index f03047a..3a1b4d5 100644 --- a/src/or/buffers.c +++ b/src/or/buffers.c @@ -12,6 +12,7 @@ **/ #define BUFFERS_PRIVATE #include "or.h" +#include "addressmap.h" #include "buffers.h" #include "config.h" #include "connection_edge.h" diff --git a/src/or/circuituse.c b/src/or/circuituse.c index ded7855..d3cde1d 100644 --- a/src/or/circuituse.c +++ b/src/or/circuituse.c @@ -10,6 +10,7 @@ **/ #include "or.h" +#include "addressmap.h" #include "channel.h" #include "circuitbuild.h" #include "circuitlist.h" diff --git a/src/or/config.c b/src/or/config.c index bf32fae..9af55e9 100644 --- a/src/or/config.c +++ b/src/or/config.c @@ -12,6 +12,7 @@ #define CONFIG_PRIVATE #include "or.h" +#include "addressmap.h" #include "channel.h" #include "circuitbuild.h" #include "circuitlist.h" diff --git a/src/or/connection_edge.c b/src/or/connection_edge.c index 162de2e..1ee88f3 100644 --- a/src/or/connection_edge.c +++ b/src/or/connection_edge.c @@ -10,6 +10,7 @@ **/ #include "or.h" +#include "addressmap.h" #include "buffers.h" #include "channel.h" #include "circuitlist.h" @@ -56,9 +57,7 @@ static int connection_ap_handshake_process_socks(entry_connection_t *conn); static int connection_ap_process_natd(entry_connection_t *conn); static int connection_exit_connect_dir(edge_connection_t *exitconn); -static int address_is_in_virtual_range(const char *addr); static int consider_plaintext_ports(entry_connection_t *conn, uint16_t port); -static void clear_trackexithost_mappings(const char *exitname); static int connection_ap_supports_optimistic_data(const entry_connection_t *); /** An AP stream has failed/finished. If it hasn't already sent back @@ -784,947 +783,6 @@ connection_ap_detach_retriable(entry_connection_t *conn, } } -/** A client-side struct to remember requests to rewrite addresses - * to new addresses. These structs are stored in the hash table - * "addressmap" below. - * - * There are 5 ways to set an address mapping: - * - A MapAddress command from the controller [permanent] - * - An AddressMap directive in the torrc [permanent] - * - When a TrackHostExits torrc directive is triggered [temporary] - * - When a DNS resolve succeeds [temporary] - * - When a DNS resolve fails [temporary] - * - * When an addressmap request is made but one is already registered, - * the new one is replaced only if the currently registered one has - * no "new_address" (that is, it's in the process of DNS resolve), - * or if the new one is permanent (expires==0 or 1). - * - * (We overload the 'expires' field, using "0" for mappings set via - * the configuration file, "1" for mappings set from the control - * interface, and other values for DNS and TrackHostExit mappings that can - * expire.) - * - * A mapping may be 'wildcarded'. If "src_wildcard" is true, then - * any address that ends with a . followed by the key for this entry will - * get remapped by it. If "dst_wildcard" is also true, then only the - * matching suffix of such addresses will get replaced by new_address. - */ -typedef struct { - char *new_address; - time_t expires; - addressmap_entry_source_t source:3; - unsigned src_wildcard:1; - unsigned dst_wildcard:1; - short num_resolve_failures; -} addressmap_entry_t; - -/** Entry for mapping addresses to which virtual address we mapped them to. */ -typedef struct { - char *ipv4_address; - char *hostname_address; -} virtaddress_entry_t; - -/** A hash table to store client-side address rewrite instructions. */ -static strmap_t *addressmap=NULL; -/** - * Table mapping addresses to which virtual address, if any, we - * assigned them to. - * - * We maintain the following invariant: if [A,B] is in - * virtaddress_reversemap, then B must be a virtual address, and [A,B] - * must be in addressmap. We do not require that the converse hold: - * if it fails, then we could end up mapping two virtual addresses to - * the same address, which is no disaster. - **/ -static strmap_t *virtaddress_reversemap=NULL; - -/** Initialize addressmap. */ -void -addressmap_init(void) -{ - addressmap = strmap_new(); - virtaddress_reversemap = strmap_new(); -} - -/** Free the memory associated with the addressmap entry _ent. */ -static void -addressmap_ent_free(void *_ent) -{ - addressmap_entry_t *ent; - if (!_ent) - return; - - ent = _ent; - tor_free(ent->new_address); - tor_free(ent); -} - -/** Free storage held by a virtaddress_entry_t* entry in ent. */ -static void -addressmap_virtaddress_ent_free(void *_ent) -{ - virtaddress_entry_t *ent; - if (!_ent) - return; - - ent = _ent; - tor_free(ent->ipv4_address); - tor_free(ent->hostname_address); - tor_free(ent); -} - -/** Free storage held by a virtaddress_entry_t* entry in ent. */ -static void -addressmap_virtaddress_remove(const char *address, addressmap_entry_t *ent) -{ - if (ent && ent->new_address && - address_is_in_virtual_range(ent->new_address)) { - virtaddress_entry_t *ve = - strmap_get(virtaddress_reversemap, ent->new_address); - /*log_fn(LOG_NOTICE,"remove reverse mapping for %s",ent->new_address);*/ - if (ve) { - if (!strcmp(address, ve->ipv4_address)) - tor_free(ve->ipv4_address); - if (!strcmp(address, ve->hostname_address)) - tor_free(ve->hostname_address); - if (!ve->ipv4_address && !ve->hostname_address) { - tor_free(ve); - strmap_remove(virtaddress_reversemap, ent->new_address); - } - } - } -} - -/** Remove ent (which must be mapped to by address) from the - * client address maps. */ -static void -addressmap_ent_remove(const char *address, addressmap_entry_t *ent) -{ - addressmap_virtaddress_remove(address, ent); - addressmap_ent_free(ent); -} - -/** Unregister all TrackHostExits mappings from any address to - * *.exitname.exit. */ -static void -clear_trackexithost_mappings(const char *exitname) -{ - char *suffix = NULL; - if (!addressmap || !exitname) - return; - tor_asprintf(&suffix, ".%s.exit", exitname); - tor_strlower(suffix); - - STRMAP_FOREACH_MODIFY(addressmap, address, addressmap_entry_t *, ent) { - if (ent->source == ADDRMAPSRC_TRACKEXIT && - !strcmpend(ent->new_address, suffix)) { - addressmap_ent_remove(address, ent); - MAP_DEL_CURRENT(address); - } - } STRMAP_FOREACH_END; - - tor_free(suffix); -} - -/** Remove all TRACKEXIT mappings from the addressmap for which the target - * host is unknown or no longer allowed, or for which the source address - * is no longer in trackexithosts. */ -void -addressmap_clear_excluded_trackexithosts(const 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; - const node_t *node; - - if (!target) { - /* DNS resolving in progress */ - continue; - } else 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 */ - while (dot > target && *dot != '.') - dot--; - if (*dot == '.') dot++; - nodename = tor_strndup(dot, len-5-(dot-target));; - node = node_get_by_nickname(nodename, 0); - tor_free(nodename); - if (!node || - (allow_nodes && !routerset_contains_node(allow_nodes, node)) || - routerset_contains_node(exclude_nodes, node) || - !hostname_in_track_host_exits(options, address)) { - /* 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 AUTOMAP mappings from the addressmap for which the - * source address no longer matches AutomapHostsSuffixes, which is - * no longer allowed by AutomapHostsOnResolve, or for which the - * target address is no longer in the virtual network. */ -void -addressmap_clear_invalid_automaps(const or_options_t *options) -{ - int clear_all = !options->AutomapHostsOnResolve; - const smartlist_t *suffixes = options->AutomapHostsSuffixes; - - if (!addressmap) - return; - - if (!suffixes) - clear_all = 1; /* This should be impossible, but let's be sure. */ - - STRMAP_FOREACH_MODIFY(addressmap, src_address, addressmap_entry_t *, ent) { - int remove = clear_all; - if (ent->source != ADDRMAPSRC_AUTOMAP) - continue; /* not an automap mapping. */ - - if (!remove) { - int suffix_found = 0; - SMARTLIST_FOREACH(suffixes, const char *, suffix, { - if (!strcasecmpend(src_address, suffix)) { - suffix_found = 1; - break; - } - }); - if (!suffix_found) - remove = 1; - } - - if (!remove && ! address_is_in_virtual_range(ent->new_address)) - remove = 1; - - if (remove) { - addressmap_ent_remove(src_address, ent); - MAP_DEL_CURRENT(src_address); - } - } STRMAP_FOREACH_END; -} - -/** Remove all entries from the addressmap that were set via the - * configuration file or the command line. */ -void -addressmap_clear_configured(void) -{ - addressmap_get_mappings(NULL, 0, 0, 0); -} - -/** Remove all entries from the addressmap that are set to expire, ever. */ -void -addressmap_clear_transient(void) -{ - addressmap_get_mappings(NULL, 2, TIME_MAX, 0); -} - -/** Clean out entries from the addressmap cache that were - * added long enough ago that they are no longer valid. - */ -void -addressmap_clean(time_t now) -{ - addressmap_get_mappings(NULL, 2, now, 0); -} - -/** Free all the elements in the addressmap, and free the addressmap - * itself. */ -void -addressmap_free_all(void) -{ - strmap_free(addressmap, addressmap_ent_free); - addressmap = NULL; - - strmap_free(virtaddress_reversemap, addressmap_virtaddress_ent_free); - virtaddress_reversemap = NULL; -} - -/** Try to find a match for AddressMap expressions that use - * wildcard notation such as '*.c.d *.e.f' (so 'a.c.d' will map to 'a.e.f') or - * '*.c.d a.b.c' (so 'a.c.d' will map to a.b.c). - * Return the matching entry in AddressMap or NULL if no match is found. - * For expressions such as '*.c.d *.e.f', truncate address 'a.c.d' - * to 'a' before we return the matching AddressMap entry. - * - * This function does not handle the case where a pattern of the form "*.c.d" - * matches the address c.d -- that's done by the main addressmap_rewrite - * function. - */ -static addressmap_entry_t * -addressmap_match_superdomains(char *address) -{ - addressmap_entry_t *val; - char *cp; - - cp = address; - while ((cp = strchr(cp, '.'))) { - /* cp now points to a suffix of address that begins with a . */ - val = strmap_get_lc(addressmap, cp+1); - if (val && val->src_wildcard) { - if (val->dst_wildcard) - *cp = '\0'; - return val; - } - ++cp; - } - return NULL; -} - -/** Look at address, and rewrite it until it doesn't want any - * more rewrites; but don't get into an infinite loop. - * Don't write more than maxlen chars into address. Return true if the - * address changed; false otherwise. Set *expires_out to the - * expiry time of the result, or to time_max if the result does - * not expire. - * - * If exit_source_out is non-null, we set it as follows. If we the - * address starts out as a non-exit address, and we remap it to an .exit - * address at any point, then set *exit_source_out to the - * address_entry_source_t of the first such rule. Set *exit_source_out - * to ADDRMAPSRC_NONE if there is no such rewrite, or if the original address - * was a .exit. - */ -int -addressmap_rewrite(char *address, size_t maxlen, time_t *expires_out, - addressmap_entry_source_t *exit_source_out) -{ - addressmap_entry_t *ent; - int rewrites; - time_t expires = TIME_MAX; - addressmap_entry_source_t exit_source = ADDRMAPSRC_NONE; - char *addr_orig = tor_strdup(address); - char *log_addr_orig = NULL; - - for (rewrites = 0; rewrites < 16; rewrites++) { - int exact_match = 0; - log_addr_orig = tor_strdup(escaped_safe_str_client(address)); - - ent = strmap_get(addressmap, address); - - if (!ent || !ent->new_address) { - ent = addressmap_match_superdomains(address); - } else { - if (ent->src_wildcard && !ent->dst_wildcard && - !strcasecmp(address, ent->new_address)) { - /* This is a rule like *.example.com example.com, and we just got - * "example.com" */ - goto done; - } - - exact_match = 1; - } - - if (!ent || !ent->new_address) { - goto done; - } - - if (ent->dst_wildcard && !exact_match) { - strlcat(address, ".", maxlen); - strlcat(address, ent->new_address, maxlen); - } else { - strlcpy(address, ent->new_address, maxlen); - } - - if (!strcmpend(address, ".exit") && - strcmpend(addr_orig, ".exit") && - exit_source == ADDRMAPSRC_NONE) { - exit_source = ent->source; - } - - log_info(LD_APP, "Addressmap: rewriting %s to %s", - log_addr_orig, escaped_safe_str_client(address)); - if (ent->expires > 1 && ent->expires < expires) - expires = ent->expires; - - tor_free(log_addr_orig); - } - log_warn(LD_CONFIG, - "Loop detected: we've rewritten %s 16 times! Using it as-is.", - escaped_safe_str_client(address)); - /* it's fine to rewrite a rewrite, but don't loop forever */ - - done: - tor_free(addr_orig); - tor_free(log_addr_orig); - if (exit_source_out) - *exit_source_out = exit_source; - if (expires_out) - *expires_out = TIME_MAX; - return (rewrites > 0); -} - -/** If we have a cached reverse DNS entry for the address stored in the - * maxlen-byte buffer address (typically, a dotted quad) then - * rewrite to the cached value and return 1. Otherwise return 0. Set - * *expires_out to the expiry time of the result, or to time_max - * if the result does not expire. */ -static int -addressmap_rewrite_reverse(char *address, size_t maxlen, time_t *expires_out) -{ - char *s, *cp; - addressmap_entry_t *ent; - int r = 0; - tor_asprintf(&s, "REVERSE[%s]", address); - ent = strmap_get(addressmap, s); - if (ent) { - cp = tor_strdup(escaped_safe_str_client(ent->new_address)); - log_info(LD_APP, "Rewrote reverse lookup %s -> %s", - escaped_safe_str_client(s), cp); - tor_free(cp); - strlcpy(address, ent->new_address, maxlen); - r = 1; - } - - if (expires_out) - *expires_out = (ent && ent->expires > 1) ? ent->expires : TIME_MAX; - - tor_free(s); - return r; -} - -/** Return 1 if address is already registered, else return 0. If address - * is already registered, and update_expires is non-zero, then update - * the expiry time on the mapping with update_expires if it is a - * mapping created by TrackHostExits. */ -int -addressmap_have_mapping(const char *address, int update_expiry) -{ - addressmap_entry_t *ent; - if (!(ent=strmap_get_lc(addressmap, address))) - return 0; - if (update_expiry && ent->source==ADDRMAPSRC_TRACKEXIT) - ent->expires=time(NULL) + update_expiry; - return 1; -} - -/** Register a request to map address to new_address, - * which will expire on expires (or 0 if never expires from - * config file, 1 if never expires from controller, 2 if never expires - * (virtual address mapping) from the controller.) - * - * new_address should be a newly dup'ed string, which we'll use or - * free as appropriate. We will leave address alone. - * - * If wildcard_addr is true, then the mapping will match any address - * equal to address, or any address ending with a period followed by - * address. If wildcard_addr and wildcard_new_addr are - * both true, the mapping will rewrite addresses that end with - * ".address" into ones that end with ".new_address." - * - * If new_address is NULL, or new_address is equal to - * address and wildcard_addr is equal to - * wildcard_new_addr, remove any mappings that exist from - * address. - * - * - * It is an error to set wildcard_new_addr if wildcard_addr is - * not set. */ -void -addressmap_register(const char *address, char *new_address, time_t expires, - addressmap_entry_source_t source, - const int wildcard_addr, - const int wildcard_new_addr) -{ - addressmap_entry_t *ent; - - if (wildcard_new_addr) - tor_assert(wildcard_addr); - - ent = strmap_get(addressmap, address); - if (!new_address || (!strcasecmp(address,new_address) && - wildcard_addr == wildcard_new_addr)) { - /* Remove the mapping, if any. */ - tor_free(new_address); - if (ent) { - addressmap_ent_remove(address,ent); - strmap_remove(addressmap, address); - } - return; - } - if (!ent) { /* make a new one and register it */ - ent = tor_malloc_zero(sizeof(addressmap_entry_t)); - strmap_set(addressmap, address, ent); - } else if (ent->new_address) { /* we need to clean up the old mapping. */ - if (expires > 1) { - log_info(LD_APP,"Temporary addressmap ('%s' to '%s') not performed, " - "since it's already mapped to '%s'", - safe_str_client(address), - safe_str_client(new_address), - safe_str_client(ent->new_address)); - tor_free(new_address); - return; - } - if (address_is_in_virtual_range(ent->new_address) && - expires != 2) { - /* XXX This isn't the perfect test; we want to avoid removing - * mappings set from the control interface _as virtual mapping */ - addressmap_virtaddress_remove(address, ent); - } - tor_free(ent->new_address); - } /* else { we have an in-progress resolve with no mapping. } */ - - ent->new_address = new_address; - ent->expires = expires==2 ? 1 : expires; - ent->num_resolve_failures = 0; - ent->source = source; - ent->src_wildcard = wildcard_addr ? 1 : 0; - ent->dst_wildcard = wildcard_new_addr ? 1 : 0; - - log_info(LD_CONFIG, "Addressmap: (re)mapped '%s' to '%s'", - safe_str_client(address), - safe_str_client(ent->new_address)); - control_event_address_mapped(address, ent->new_address, expires, NULL); -} - -/** An attempt to resolve address failed at some OR. - * Increment the number of resolve failures we have on record - * for it, and then return that number. - */ -int -client_dns_incr_failures(const char *address) -{ - addressmap_entry_t *ent = strmap_get(addressmap, address); - if (!ent) { - ent = tor_malloc_zero(sizeof(addressmap_entry_t)); - ent->expires = time(NULL) + MAX_DNS_ENTRY_AGE; - strmap_set(addressmap,address,ent); - } - if (ent->num_resolve_failures < SHORT_MAX) - ++ent->num_resolve_failures; /* don't overflow */ - log_info(LD_APP, "Address %s now has %d resolve failures.", - safe_str_client(address), - ent->num_resolve_failures); - return ent->num_resolve_failures; -} - -/** If address is in the client DNS addressmap, reset - * the number of resolve failures we have on record for it. - * This is used when we fail a stream because it won't resolve: - * otherwise future attempts on that address will only try once. - */ -void -client_dns_clear_failures(const char *address) -{ - addressmap_entry_t *ent = strmap_get(addressmap, address); - if (ent) - ent->num_resolve_failures = 0; -} - -/** Record the fact that address resolved to name. - * We can now use this in subsequent streams via addressmap_rewrite() - * so we can more correctly choose an exit that will allow address. - * - * If exitname is defined, then append the addresses with - * ".exitname.exit" before registering the mapping. - * - * If ttl is nonnegative, the mapping will be valid for - * ttlseconds; otherwise, we use the default. - */ -static void -client_dns_set_addressmap_impl(const char *address, const char *name, - const char *exitname, - int ttl) -{ - /* <address>.<hex or nickname>.exit\0 or just <address>\0 */ - char extendedaddress[MAX_SOCKS_ADDR_LEN+MAX_VERBOSE_NICKNAME_LEN+10]; - /* 123.123.123.123.<hex or nickname>.exit\0 or just 123.123.123.123\0 */ - char extendedval[INET_NTOA_BUF_LEN+MAX_VERBOSE_NICKNAME_LEN+10]; - - tor_assert(address); - tor_assert(name); - - if (ttl<0) - ttl = DEFAULT_DNS_TTL; - else - ttl = dns_clip_ttl(ttl); - - if (exitname) { - /* XXXX fails to ever get attempts to get an exit address of - * google.com.digest[=~]nickname.exit; we need a syntax for this that - * won't make strict RFC952-compliant applications (like us) barf. */ - tor_snprintf(extendedaddress, sizeof(extendedaddress), - "%s.%s.exit", address, exitname); - tor_snprintf(extendedval, sizeof(extendedval), - "%s.%s.exit", name, exitname); - } else { - tor_snprintf(extendedaddress, sizeof(extendedaddress), - "%s", address); - tor_snprintf(extendedval, sizeof(extendedval), - "%s", name); - } - addressmap_register(extendedaddress, tor_strdup(extendedval), - time(NULL) + ttl, ADDRMAPSRC_DNS, 0, 0); -} - -/** Record the fact that address resolved to val. - * We can now use this in subsequent streams via addressmap_rewrite() - * so we can more correctly choose an exit that will allow address. - * - * If exitname is defined, then append the addresses with - * ".exitname.exit" before registering the mapping. - * - * If ttl is nonnegative, the mapping will be valid for - * ttlseconds; otherwise, we use the default. - */ -void -client_dns_set_addressmap(const char *address, uint32_t val, - const char *exitname, - int ttl) -{ - struct in_addr in; - char valbuf[INET_NTOA_BUF_LEN]; - - tor_assert(address); - - if (tor_inet_aton(address, &in)) - return; /* If address was an IP address already, don't add a mapping. */ - in.s_addr = htonl(val); - tor_inet_ntoa(&in,valbuf,sizeof(valbuf)); - - client_dns_set_addressmap_impl(address, valbuf, exitname, ttl); -} - -/** Add a cache entry noting that address (ordinarily a dotted quad) - * resolved via a RESOLVE_PTR request to the hostname v. - * - * If exitname is defined, then append the addresses with - * ".exitname.exit" before registering the mapping. - * - * If ttl is nonnegative, the mapping will be valid for - * ttlseconds; otherwise, we use the default. - */ -static void -client_dns_set_reverse_addressmap(const char *address, const char *v, - const char *exitname, - int ttl) -{ - char *s = NULL; - tor_asprintf(&s, "REVERSE[%s]", address); - client_dns_set_addressmap_impl(s, v, exitname, ttl); - tor_free(s); -} - -/* By default, we hand out 127.192.0.1 through 127.254.254.254. - * These addresses should map to localhost, so even if the - * application accidentally tried to connect to them directly (not - * via Tor), it wouldn't get too far astray. - * - * These options are configured by parse_virtual_addr_network(). - */ -/** Which network should we use for virtual IPv4 addresses? Only the first - * bits of this value are fixed. */ -static uint32_t virtual_addr_network = 0x7fc00000u; -/** How many bits of virtual_addr_network are fixed? */ -static maskbits_t virtual_addr_netmask_bits = 10; -/** What's the next virtual address we will hand out? */ -static uint32_t next_virtual_addr = 0x7fc00000u; - -/** Read a netmask of the form 127.192.0.0/10 from "val", and check whether - * it's a valid set of virtual addresses to hand out in response to MAPADDRESS - * requests. Return 0 on success; set *msg (if provided) to a newly allocated - * string and return -1 on failure. If validate_only is false, sets the - * actual virtual address range to the parsed value. */ -int -parse_virtual_addr_network(const char *val, int validate_only, - char **msg) -{ - uint32_t addr; - uint16_t port_min, port_max; - maskbits_t bits; - - if (parse_addr_and_port_range(val, &addr, &bits, &port_min, &port_max)) { - if (msg) *msg = tor_strdup("Error parsing VirtualAddressNetwork"); - return -1; - } - - if (port_min != 1 || port_max != 65535) { - if (msg) *msg = tor_strdup("Can't specify ports on VirtualAddressNetwork"); - return -1; - } - - if (bits > 16) { - if (msg) *msg = tor_strdup("VirtualAddressNetwork expects a /16 " - "network or larger"); - return -1; - } - - if (validate_only) - return 0; - - virtual_addr_network = (uint32_t)( addr & (0xfffffffful << (32-bits)) ); - virtual_addr_netmask_bits = bits; - - if (addr_mask_cmp_bits(next_virtual_addr, addr, bits)) - next_virtual_addr = addr; - - return 0; -} - -/** - * Return true iff addr is likely to have been returned by - * client_dns_get_unused_address. - **/ -static int -address_is_in_virtual_range(const char *address) -{ - struct in_addr in; - tor_assert(address); - if (!strcasecmpend(address, ".virtual")) { - return 1; - } else if (tor_inet_aton(address, &in)) { - uint32_t addr = ntohl(in.s_addr); - if (!addr_mask_cmp_bits(addr, virtual_addr_network, - virtual_addr_netmask_bits)) - return 1; - } - return 0; -} - -/** Increment the value of next_virtual_addr; reset it to the start of the - * virtual address range if it wraps around. - */ -static INLINE void -increment_virtual_addr(void) -{ - ++next_virtual_addr; - if (addr_mask_cmp_bits(next_virtual_addr, virtual_addr_network, - virtual_addr_netmask_bits)) - next_virtual_addr = virtual_addr_network; -} - -/** Return a newly allocated string holding an address of type - * (one of RESOLVED_TYPE_{IPV4|HOSTNAME}) that has not yet been mapped, - * and that is very unlikely to be the address of any real host. - * - * May return NULL if we have run out of virtual addresses. - */ -static char * -addressmap_get_virtual_address(int type) -{ - char buf[64]; - tor_assert(addressmap); - - if (type == RESOLVED_TYPE_HOSTNAME) { - char rand[10]; - do { - crypto_rand(rand, sizeof(rand)); - base32_encode(buf,sizeof(buf),rand,sizeof(rand)); - strlcat(buf, ".virtual", sizeof(buf)); - } while (strmap_get(addressmap, buf)); - return tor_strdup(buf); - } else if (type == RESOLVED_TYPE_IPV4) { - // This is an imperfect estimate of how many addresses are available, but - // that's ok. - struct in_addr in; - uint32_t available = 1u << (32-virtual_addr_netmask_bits); - while (available) { - /* Don't hand out any .0 or .255 address. */ - while ((next_virtual_addr & 0xff) == 0 || - (next_virtual_addr & 0xff) == 0xff) { - increment_virtual_addr(); - if (! --available) { - log_warn(LD_CONFIG, "Ran out of virtual addresses!"); - return NULL; - } - } - in.s_addr = htonl(next_virtual_addr); - tor_inet_ntoa(&in, buf, sizeof(buf)); - if (!strmap_get(addressmap, buf)) { - increment_virtual_addr(); - break; - } - - increment_virtual_addr(); - --available; - // log_info(LD_CONFIG, "%d addrs available", (int)available); - if (! available) { - log_warn(LD_CONFIG, "Ran out of virtual addresses!"); - return NULL; - } - } - return tor_strdup(buf); - } else { - log_warn(LD_BUG, "Called with unsupported address type (%d)", type); - return NULL; - } -} - -/** A controller has requested that we map some address of type - * type to the address new_address. Choose an address - * that is unlikely to be used, and map it, and return it in a newly - * allocated string. If another address of the same type is already - * mapped to new_address, try to return a copy of that address. - * - * The string in new_address may be freed or inserted into a map - * as appropriate. May return NULL if are out of virtual addresses. - **/ -const char * -addressmap_register_virtual_address(int type, char *new_address) -{ - char **addrp; - virtaddress_entry_t *vent; - int vent_needs_to_be_added = 0; - - tor_assert(new_address); - tor_assert(addressmap); - tor_assert(virtaddress_reversemap); - - vent = strmap_get(virtaddress_reversemap, new_address); - if (!vent) { - vent = tor_malloc_zero(sizeof(virtaddress_entry_t)); - vent_needs_to_be_added = 1; - } - - addrp = (type == RESOLVED_TYPE_IPV4) ? - &vent->ipv4_address : &vent->hostname_address; - if (*addrp) { - addressmap_entry_t *ent = strmap_get(addressmap, *addrp); - if (ent && ent->new_address && - !strcasecmp(new_address, ent->new_address)) { - tor_free(new_address); - tor_assert(!vent_needs_to_be_added); - return tor_strdup(*addrp); - } else - log_warn(LD_BUG, - "Internal confusion: I thought that '%s' was mapped to by " - "'%s', but '%s' really maps to '%s'. This is a harmless bug.", - safe_str_client(new_address), - safe_str_client(*addrp), - safe_str_client(*addrp), - ent?safe_str_client(ent->new_address):"(nothing)"); - } - - tor_free(*addrp); - *addrp = addressmap_get_virtual_address(type); - if (!*addrp) { - tor_free(vent); - tor_free(new_address); - return NULL; - } - log_info(LD_APP, "Registering map from %s to %s", *addrp, new_address); - if (vent_needs_to_be_added) - strmap_set(virtaddress_reversemap, new_address, vent); - addressmap_register(*addrp, new_address, 2, ADDRMAPSRC_AUTOMAP, 0, 0); - -#if 0 - { - /* Try to catch possible bugs */ - addressmap_entry_t *ent; - ent = strmap_get(addressmap, *addrp); - tor_assert(ent); - tor_assert(!strcasecmp(ent->new_address,new_address)); - vent = strmap_get(virtaddress_reversemap, new_address); - tor_assert(vent); - tor_assert(!strcasecmp(*addrp, - (type == RESOLVED_TYPE_IPV4) ? - vent->ipv4_address : vent->hostname_address)); - log_info(LD_APP, "Map from %s to %s okay.", - safe_str_client(*addrp), - safe_str_client(new_address)); - } -#endif - - return *addrp; -} - -/** Return 1 if address has funny characters in it like colons. Return - * 0 if it's fine, or if we're configured to allow it anyway. client - * should be true if we're using this address as a client; false if we're - * using it as a server. - */ -int -address_is_invalid_destination(const char *address, int client) -{ - if (client) { - if (get_options()->AllowNonRFC953Hostnames) - return 0; - } else { - if (get_options()->ServerDNSAllowNonRFC953Hostnames) - return 0; - } - - while (*address) { - if (TOR_ISALNUM(*address) || - *address == '-' || - *address == '.' || - *address == '_') /* Underscore is not allowed, but Windows does it - * sometimes, just to thumb its nose at the IETF. */ - ++address; - else - return 1; - } - return 0; -} - -/** Iterate over all address mappings which have expiry times between - * min_expires and max_expires, inclusive. If sl is provided, add an - * "old-addr new-addr expiry" string to sl for each mapping, omitting - * the expiry time if want_expiry is false. If sl is NULL, remove the - * mappings. - */ -void -addressmap_get_mappings(smartlist_t *sl, time_t min_expires, - time_t max_expires, int want_expiry) -{ - strmap_iter_t *iter; - const char *key; - void *val_; - addressmap_entry_t *val; - - if (!addressmap) - addressmap_init(); - - for (iter = strmap_iter_init(addressmap); !strmap_iter_done(iter); ) { - strmap_iter_get(iter, &key, &val_); - val = val_; - if (val->expires >= min_expires && val->expires <= max_expires) { - if (!sl) { - iter = strmap_iter_next_rmv(addressmap,iter); - addressmap_ent_remove(key, val); - continue; - } else if (val->new_address) { - const char *src_wc = val->src_wildcard ? "*." : ""; - const char *dst_wc = val->dst_wildcard ? "*." : ""; - if (want_expiry) { - if (val->expires < 3 || val->expires == TIME_MAX) - smartlist_add_asprintf(sl, "%s%s %s%s NEVER", - src_wc, key, dst_wc, val->new_address); - else { - char time[ISO_TIME_LEN+1]; - format_iso_time(time, val->expires); - smartlist_add_asprintf(sl, "%s%s %s%s \"%s\"", - src_wc, key, dst_wc, val->new_address, - time); - } - } else { - smartlist_add_asprintf(sl, "%s%s %s%s", - src_wc, key, dst_wc, val->new_address); - } - } - } - iter = strmap_iter_next(addressmap,iter); - } -} /** Check if conn is using a dangerous port. Then warn and/or * reject depending on our config options. */ diff --git a/src/or/connection_edge.h b/src/or/connection_edge.h index 42fb73c..b5938b3 100644 --- a/src/or/connection_edge.h +++ b/src/or/connection_edge.h @@ -67,30 +67,6 @@ int connection_ap_process_transparent(entry_connection_t *conn); int address_is_invalid_destination(const char *address, int client); -void addressmap_init(void); -void addressmap_clear_excluded_trackexithosts(const or_options_t *options); -void addressmap_clear_invalid_automaps(const or_options_t *options); -void addressmap_clean(time_t now); -void addressmap_clear_configured(void); -void addressmap_clear_transient(void); -void addressmap_free_all(void); -int addressmap_rewrite(char *address, size_t maxlen, time_t *expires_out, - addressmap_entry_source_t *exit_source_out); -int addressmap_have_mapping(const char *address, int update_timeout); - -void addressmap_register(const char *address, char *new_address, - time_t expires, addressmap_entry_source_t source, - const int address_wildcard, - const int new_address_wildcard); -int parse_virtual_addr_network(const char *val, int validate_only, - char **msg); -int client_dns_incr_failures(const char *address); -void client_dns_clear_failures(const char *address); -void client_dns_set_addressmap(const char *address, uint32_t val, - const char *exitname, int ttl); -const char *addressmap_register_virtual_address(int type, char *new_address); -void addressmap_get_mappings(smartlist_t *sl, time_t min_expires, - time_t max_expires, int want_expiry); int connection_ap_rewrite_and_attach_if_allowed(entry_connection_t *conn, origin_circuit_t *circ, crypt_path_t *cpath); diff --git a/src/or/control.c b/src/or/control.c index ad2f278..c6a66ae 100644 --- a/src/or/control.c +++ b/src/or/control.c @@ -11,6 +11,7 @@ #define CONTROL_PRIVATE #include "or.h" +#include "addressmap.h" #include "buffers.h" #include "channel.h" #include "channeltls.h" diff --git a/src/or/include.am b/src/or/include.am index 01f4784..405cbd0 100644 --- a/src/or/include.am +++ b/src/or/include.am @@ -16,6 +16,7 @@ evdns_source=src/ext/eventdns.c endif src_or_libtor_a_SOURCES = \ + src/or/addressmap.c \ src/or/buffers.c \ src/or/channel.c \ src/or/channeltls.c \ @@ -91,6 +92,7 @@ src_or_tor_LDADD = src/or/libtor.a src/common/libor.a src/common/libor-crypto.a @TOR_LIB_WS32@ @TOR_LIB_GDI@ ORHEADERS = \ + src/or/addressmap.h \ src/or/buffers.h \ src/or/channel.h \ src/or/channeltls.h \ diff --git a/src/or/main.c b/src/or/main.c index fd8f941..446836a 100644 --- a/src/or/main.c +++ b/src/or/main.c @@ -12,6 +12,7 @@ #define MAIN_PRIVATE #include "or.h" +#include "addressmap.h" #include "buffers.h" #include "channel.h" #include "channeltls.h" diff --git a/src/or/relay.c b/src/or/relay.c index 0f0d1df..25fc2e7 100644 --- a/src/or/relay.c +++ b/src/or/relay.c @@ -12,6 +12,7 @@ #define RELAY_PRIVATE #include "or.h" +#include "addressmap.h" #include "buffers.h" #include "channel.h" #include "circuitbuild.h" diff --git a/src/test/test_config.c b/src/test/test_config.c index d9fcd8b..e04b9df 100644 --- a/src/test/test_config.c +++ b/src/test/test_config.c @@ -5,6 +5,7 @@ #include "orconfig.h" #include "or.h" +#include "addressmap.h" #include "config.h" #include "confparse.h" #include "connection_edge.h"

1 0

[tor/master] Make dns wildcarding checks work for ipv6
by nickm＠torproject.org 15 Nov '12

15 Nov '12

commit 00633b944672458bdfd3d79bab4e1230cee4a522 Author: Nick Mathewson <nickm(a)torproject.org> Date: Sat Oct 27 16:07:25 2012 -0400 Make dns wildcarding checks work for ipv6 --- src/or/dns.c | 93 ++++++++++++++++++++++++++++++++++++++-------------------- 1 files changed, 61 insertions(+), 32 deletions(-) diff --git a/src/or/dns.c b/src/or/dns.c index d26314a..c590e01 100644 --- a/src/or/dns.c +++ b/src/or/dns.c @@ -1506,8 +1506,8 @@ static int dns_wildcarded_test_address_notice_given = 0; /** True iff all addresses seem to be getting wildcarded. */ static int dns_is_completely_invalid = 0; -/** Called when we see id (a dotted quad) in response to a request for - * a hopefully bogus address. */ +/** Called when we see id (a dotted quad or IPv6 address) in response + * to a request for a hopefully bogus address. */ static void wildcard_increment_answer(const char *id) { @@ -1579,17 +1579,27 @@ evdns_wildcard_check_callback(int result, char type, int count, int ttl, { (void)ttl; ++n_wildcard_requests; - if (result == DNS_ERR_NONE && type == DNS_IPv4_A && count) { - uint32_t *addrs = addresses; - int i; + if (result == DNS_ERR_NONE && count) { char *string_address = arg; - for (i = 0; i < count; ++i) { - char answer_buf[INET_NTOA_BUF_LEN+1]; - struct in_addr in; - in.s_addr = addrs[i]; - tor_inet_ntoa(&in, answer_buf, sizeof(answer_buf)); - wildcard_increment_answer(answer_buf); + int i; + if (type == DNS_IPv4_A) { + const uint32_t *addrs = addresses; + for (i = 0; i < count; ++i) { + char answer_buf[INET_NTOA_BUF_LEN+1]; + struct in_addr in; + in.s_addr = addrs[i]; + tor_inet_ntoa(&in, answer_buf, sizeof(answer_buf)); + wildcard_increment_answer(answer_buf); + } + } else if (type == DNS_IPv6_AAAA) { + const struct in6_addr *addrs = addresses; + for (i = 0; i < count; ++i) { + char answer_buf[TOR_ADDR_BUF_LEN+1]; + tor_inet_ntop(AF_INET6, &addrs[i], answer_buf, sizeof(answer_buf)); + wildcard_increment_answer(answer_buf); + } } + log(dns_wildcard_one_notice_given ? LOG_INFO : LOG_NOTICE, LD_EXIT, "Your DNS provider gave an answer for \"%s\", which " "is not supposed to exist. Apparently they are hijacking " @@ -1606,7 +1616,8 @@ evdns_wildcard_check_callback(int result, char type, int count, int ttl, * min_len and max_len random (plausible) characters followed by * suffix */ static void -launch_wildcard_check(int min_len, int max_len, const char *suffix) +launch_wildcard_check(int min_len, int max_len, int is_ipv6, + const char *suffix) { char *addr; struct evdns_request *req; @@ -1616,7 +1627,15 @@ launch_wildcard_check(int min_len, int max_len, const char *suffix) "domains with request for bogus hostname \"%s\"", addr); tor_assert(the_evdns_base); - req = evdns_base_resolve_ipv4( + if (is_ipv6) + req = evdns_base_resolve_ipv6( + the_evdns_base, + /* This "addr" tells us which address to resolve */ + addr, + DNS_QUERY_NO_SEARCH, evdns_wildcard_check_callback, + /* This "addr" is an argument to the callback*/ addr); + else + req = evdns_base_resolve_ipv4( the_evdns_base, /* This "addr" tells us which address to resolve */ addr, @@ -1661,6 +1680,14 @@ launch_test_addresses(int fd, short event, void *args) escaped_safe_str(address)); tor_free(a); } + a = tor_strdup(address); + req = evdns_base_resolve_ipv6(the_evdns_base, + address, DNS_QUERY_NO_SEARCH, evdns_callback, a); + if (!req) { + log_info(LD_EXIT, "eventdns rejected test address %s", + escaped_safe_str(address)); + tor_free(a); + } } SMARTLIST_FOREACH_END(address); } @@ -1673,27 +1700,29 @@ launch_test_addresses(int fd, short event, void *args) static void dns_launch_wildcard_checks(void) { - int i; + int i, ipv6; log_info(LD_EXIT, "Launching checks to see whether our nameservers like " "to hijack DNS failures."); - for (i = 0; i < N_WILDCARD_CHECKS; ++i) { - /* RFC2606 reserves these. Sadly, some DNS hijackers, in a silly attempt - * to 'comply' with rfc2606, refrain from giving A records for these. - * This is the standards-compliance equivalent of making sure that your - * crackhouse's elevator inspection certificate is up to date. - */ - launch_wildcard_check(2, 16, ".invalid"); - launch_wildcard_check(2, 16, ".test"); - - /* These will break specs if there are ever any number of - * 8+-character top-level domains. */ - launch_wildcard_check(8, 16, ""); - - /* Try some random .com/org/net domains. This will work fine so long as - * not too many resolve to the same place. */ - launch_wildcard_check(8, 16, ".com"); - launch_wildcard_check(8, 16, ".org"); - launch_wildcard_check(8, 16, ".net"); + for (ipv6 = 0; ipv6 <= 1; ++ipv6) { + for (i = 0; i < N_WILDCARD_CHECKS; ++i) { + /* RFC2606 reserves these. Sadly, some DNS hijackers, in a silly + * attempt to 'comply' with rfc2606, refrain from giving A records for + * these. This is the standards-compliance equivalent of making sure + * that your crackhouse's elevator inspection certificate is up to date. + */ + launch_wildcard_check(2, 16, ipv6, ".invalid"); + launch_wildcard_check(2, 16, ipv6, ".test"); + + /* These will break specs if there are ever any number of + * 8+-character top-level domains. */ + launch_wildcard_check(8, 16, ipv6, ""); + + /* Try some random .com/org/net domains. This will work fine so long as + * not too many resolve to the same place. */ + launch_wildcard_check(8, 16, ipv6, ".com"); + launch_wildcard_check(8, 16, ipv6, ".org"); + launch_wildcard_check(8, 16, ipv6, ".net"); + } } }

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[tor/master] Get the client side of receiving an IPv6 address to work
by nickm＠torproject.org 15 Nov '12

15 Nov '12

commit cac5335195d3bb9a39af77886992ffa98b8c7817 Author: Nick Mathewson <nickm(a)torproject.org> Date: Wed Oct 31 18:27:48 2012 -0400 Get the client side of receiving an IPv6 address to work This makes it so we can handle getting an IPv6 in the 3 different formats we specified it for in RESOLVED cells, END_STREAM_REASON_EXITPOLICY cells, and CONNECTED cells. We don't cache IPv6 addresses yet, since proposal 205 isn't implemented. There's a refactored function for parsing connected cells; it has unit tests. --- src/or/addressmap.c | 35 ++++++----- src/or/addressmap.h | 2 +- src/or/connection_edge.c | 15 ++++- src/or/connection_edge.h | 1 + src/or/relay.c | 134 ++++++++++++++++++++++++++++++++--------- src/or/relay.h | 2 + src/test/test_cell_formats.c | 114 +++++++++++++++++++++++++++++++++++ 7 files changed, 254 insertions(+), 49 deletions(-) diff --git a/src/or/addressmap.c b/src/or/addressmap.c index 4aa46fc..45e29c1 100644 --- a/src/or/addressmap.c +++ b/src/or/addressmap.c @@ -576,10 +576,7 @@ client_dns_set_addressmap_impl(origin_circuit_t *on_circ, const char *exitname, int ttl) { - /* <address>.<hex or nickname>.exit\0 or just <address>\0 */ - char extendedaddress[MAX_SOCKS_ADDR_LEN+MAX_VERBOSE_NICKNAME_LEN+10]; - /* 123.123.123.123.<hex or nickname>.exit\0 or just 123.123.123.123\0 */ - char extendedval[INET_NTOA_BUF_LEN+MAX_VERBOSE_NICKNAME_LEN+10]; + char *extendedaddress=NULL, *extendedval=NULL; (void)on_circ; tor_assert(address); @@ -594,18 +591,19 @@ client_dns_set_addressmap_impl(origin_circuit_t *on_circ, /* XXXX fails to ever get attempts to get an exit address of * google.com.digest[=~]nickname.exit; we need a syntax for this that * won't make strict RFC952-compliant applications (like us) barf. */ - tor_snprintf(extendedaddress, sizeof(extendedaddress), + tor_asprintf(&extendedaddress, "%s.%s.exit", address, exitname); - tor_snprintf(extendedval, sizeof(extendedval), + tor_asprintf(&extendedval, "%s.%s.exit", name, exitname); } else { - tor_snprintf(extendedaddress, sizeof(extendedaddress), + tor_asprintf(&extendedaddress, "%s", address); - tor_snprintf(extendedval, sizeof(extendedval), + tor_asprintf(&extendedval, "%s", name); } - addressmap_register(extendedaddress, tor_strdup(extendedval), + addressmap_register(extendedaddress, extendedval, time(NULL) + ttl, ADDRMAPSRC_DNS, 0, 0); + tor_free(extendedaddress); } /** Record the fact that address resolved to val. @@ -620,19 +618,26 @@ client_dns_set_addressmap_impl(origin_circuit_t *on_circ, */ void client_dns_set_addressmap(origin_circuit_t *on_circ, - const char *address, uint32_t val, + const char *address, + const tor_addr_t *val, const char *exitname, int ttl) { - struct in_addr in; - char valbuf[INET_NTOA_BUF_LEN]; + tor_addr_t addr_tmp; + char valbuf[TOR_ADDR_BUF_LEN]; tor_assert(address); + tor_assert(val); - if (tor_inet_aton(address, &in)) + if (tor_addr_parse(&addr_tmp, address) == 0) return; /* If address was an IP address already, don't add a mapping. */ - in.s_addr = htonl(val); - tor_inet_ntoa(&in,valbuf,sizeof(valbuf)); + + /* XXXXX For now, don't cache IPv6 addresses. */ + if (tor_addr_family(val) != AF_INET) + return; + + if (! tor_addr_to_str(valbuf, val, sizeof(valbuf), 0)) /* XXXX decorate? */ + return; client_dns_set_addressmap_impl(on_circ, address, valbuf, exitname, ttl); } diff --git a/src/or/addressmap.h b/src/or/addressmap.h index dd8fc9b..9b07341 100644 --- a/src/or/addressmap.h +++ b/src/or/addressmap.h @@ -29,7 +29,7 @@ int parse_virtual_addr_network(const char *val, int validate_only, int client_dns_incr_failures(const char *address); void client_dns_clear_failures(const char *address); void client_dns_set_addressmap(origin_circuit_t *on_circ, - const char *address, uint32_t val, + const char *address, const tor_addr_t *val, const char *exitname, int ttl); const char *addressmap_register_virtual_address(int type, char *new_address); void addressmap_get_mappings(smartlist_t *sl, time_t min_expires, diff --git a/src/or/connection_edge.c b/src/or/connection_edge.c index dc7d863..969128f 100644 --- a/src/or/connection_edge.c +++ b/src/or/connection_edge.c @@ -1949,10 +1949,19 @@ connection_ap_handshake_socks_resolved(entry_connection_t *conn, if (CIRCUIT_IS_ORIGIN(circ)) /* should always be true */ origin_circ = TO_ORIGIN_CIRCUIT(circ); if (answer_type == RESOLVED_TYPE_IPV4 && answer_len == 4) { - uint32_t a = ntohl(get_uint32(answer)); - if (a) { + tor_addr_t a; + tor_addr_from_ipv4n(&a, get_uint32(answer)); + if (! tor_addr_is_null(&a)) { client_dns_set_addressmap(origin_circ, - conn->socks_request->address, a, + conn->socks_request->address, &a, + conn->chosen_exit_name, ttl); + } + } else if (answer_type == RESOLVED_TYPE_IPV6 && answer_len == 16) { + tor_addr_t a; + tor_addr_from_ipv6_bytes(&a, (char*)answer); + if (! tor_addr_is_null(&a)) { + client_dns_set_addressmap(origin_circ, + conn->socks_request->address, &a, conn->chosen_exit_name, ttl); } } else if (answer_type == RESOLVED_TYPE_HOSTNAME && answer_len < 256) { diff --git a/src/or/connection_edge.h b/src/or/connection_edge.h index 39f492d..9c4318c 100644 --- a/src/or/connection_edge.h +++ b/src/or/connection_edge.h @@ -108,6 +108,7 @@ typedef struct begin_cell_t { int begin_cell_parse(const cell_t *cell, begin_cell_t *bcell, uint8_t *end_reason_out); + #endif diff --git a/src/or/relay.c b/src/or/relay.c index 76e9d25..a05e955 100644 --- a/src/or/relay.c +++ b/src/or/relay.c @@ -705,21 +705,37 @@ connection_ap_process_end_not_open( switch (reason) { case END_STREAM_REASON_EXITPOLICY: if (rh->length >= 5) { - uint32_t addr = ntohl(get_uint32(cell->payload+RELAY_HEADER_SIZE+1)); - int ttl; - if (!addr) { + tor_addr_t addr; + int ttl = -1; + tor_addr_make_unspec(&addr); + if (rh->length == 5 || rh->length == 9) { + tor_addr_from_ipv4n(&addr, + get_uint32(cell->payload+RELAY_HEADER_SIZE+1)); + if (rh->length == 9) + ttl = (int)ntohl(get_uint32(cell->payload+RELAY_HEADER_SIZE+5)); + } else if (rh->length == 17 || rh->length == 21) { + tor_addr_from_ipv6_bytes(&addr, + (char*)(cell->payload+RELAY_HEADER_SIZE+1)); + if (rh->length == 21) + ttl = (int)ntohl(get_uint32(cell->payload+RELAY_HEADER_SIZE+17)); + } + if (tor_addr_is_null(&addr)) { log_info(LD_APP,"Address '%s' resolved to 0.0.0.0. Closing,", safe_str(conn->socks_request->address)); connection_mark_unattached_ap(conn, END_STREAM_REASON_TORPROTOCOL); return 0; } - if (rh->length >= 9) - ttl = (int)ntohl(get_uint32(cell->payload+RELAY_HEADER_SIZE+5)); - else - ttl = -1; + if ((tor_addr_family(&addr) == AF_INET && !conn->ipv4_traffic_ok) || + (tor_addr_family(&addr) == AF_INET6 && !conn->ipv6_traffic_ok)) { + log_fn(LOG_PROTOCOL_WARN, LD_APP, + "Got an EXITPOLICY failure on a connection with a " + "mismatched family. Closing."); + connection_mark_unattached_ap(conn, END_STREAM_REASON_TORPROTOCOL); + return 0; + } if (get_options()->ClientDNSRejectInternalAddresses && - is_internal_IP(addr, 0)) { + tor_addr_is_internal(&addr, 0)) { log_info(LD_APP,"Address '%s' resolved to internal. Closing,", safe_str(conn->socks_request->address)); connection_mark_unattached_ap(conn, END_STREAM_REASON_TORPROTOCOL); @@ -727,7 +743,7 @@ connection_ap_process_end_not_open( } client_dns_set_addressmap(circ, - conn->socks_request->address, addr, + conn->socks_request->address, &addr, conn->chosen_exit_name, ttl); } /* check if he *ought* to have allowed it */ @@ -830,20 +846,56 @@ connection_ap_process_end_not_open( } /** Helper: change the socks_request->address field on conn to the - * dotted-quad representation of new_addr (given in host order), + * dotted-quad representation of new_addr, * and send an appropriate REMAP event. */ static void -remap_event_helper(entry_connection_t *conn, uint32_t new_addr) +remap_event_helper(entry_connection_t *conn, const tor_addr_t *new_addr) { - struct in_addr in; - - in.s_addr = htonl(new_addr); - tor_inet_ntoa(&in, conn->socks_request->address, - sizeof(conn->socks_request->address)); + tor_addr_to_str(conn->socks_request->address, new_addr, + sizeof(conn->socks_request->address), + 0); /* XXXXX Should decorate be 1? */ control_event_stream_status(conn, STREAM_EVENT_REMAP, REMAP_STREAM_SOURCE_EXIT); } +/**DOCDOC*/ +int +connected_cell_parse(const relay_header_t *rh, const cell_t *cell, + tor_addr_t *addr_out, int *ttl_out) +{ + uint32_t bytes; + const uint8_t *payload = cell->payload + RELAY_HEADER_SIZE; + + tor_addr_make_unspec(addr_out); + *ttl_out = -1; + if (rh->length == 0) + return 0; + if (rh->length < 4) + return -1; + bytes = ntohl(get_uint32(payload)); + + /* If bytes is 0, this is maybe a v6 address. Otherwise it's a v4 address */ + if (bytes != 0) { + /* v4 address */ + tor_addr_from_ipv4h(addr_out, bytes); + if (rh->length >= 8) { + bytes = ntohl(get_uint32(payload + 4)); + if (bytes <= INT32_MAX) + *ttl_out = bytes; + } + } else { + if (rh->length < 25) /* 4 bytes of 0s, 1 addr, 16 ipv4, 4 ttl. */ + return -1; + if (get_uint8(payload + 4) != 6) + return -1; + tor_addr_from_ipv6_bytes(addr_out, (char*)(payload + 5)); + bytes = ntohl(get_uint32(payload + 21)); + if (bytes <= INT32_MAX) + *ttl_out = (int) bytes; + } + return 0; +} + /** An incoming relay cell has arrived from circuit circ to * stream conn. * @@ -874,6 +926,8 @@ connection_edge_process_relay_cell_not_open( if (conn->base_.type == CONN_TYPE_AP && rh->command == RELAY_COMMAND_CONNECTED) { + tor_addr_t addr; + int ttl; entry_connection_t *entry_conn = EDGE_TO_ENTRY_CONN(conn); tor_assert(CIRCUIT_IS_ORIGIN(circ)); if (conn->base_.state != AP_CONN_STATE_CONNECT_WAIT) { @@ -884,27 +938,41 @@ connection_edge_process_relay_cell_not_open( conn->base_.state = AP_CONN_STATE_OPEN; log_info(LD_APP,"'connected' received after %d seconds.", (int)(time(NULL) - conn->base_.timestamp_lastread)); - if (rh->length >= 4) { - uint32_t addr = ntohl(get_uint32(cell->payload+RELAY_HEADER_SIZE)); - int ttl; - if (!addr || (get_options()->ClientDNSRejectInternalAddresses && - is_internal_IP(addr, 0))) { + if (connected_cell_parse(rh, cell, &addr, &ttl) < 0) { + log_fn(LOG_PROTOCOL_WARN, LD_APP, + "Got a badly formatted connected cell. Closing."); + connection_edge_end(conn, END_STREAM_REASON_TORPROTOCOL); + connection_mark_unattached_ap(entry_conn, END_STREAM_REASON_TORPROTOCOL); + } + if (tor_addr_family(&addr) != AF_UNSPEC) { + const sa_family_t family = tor_addr_family(&addr); + if (tor_addr_is_null(&addr) || + (get_options()->ClientDNSRejectInternalAddresses && + tor_addr_is_internal(&addr, 0))) { log_info(LD_APP, "...but it claims the IP address was %s. Closing.", - fmt_addr32(addr)); + fmt_addr(&addr)); + connection_edge_end(conn, END_STREAM_REASON_TORPROTOCOL); + connection_mark_unattached_ap(entry_conn, + END_STREAM_REASON_TORPROTOCOL); + return 0; + } + + if ((family == AF_INET && ! entry_conn->ipv4_traffic_ok) || + (family == AF_INET6 && ! entry_conn->ipv6_traffic_ok)) { + log_fn(LOG_PROTOCOL_WARN, LD_APP, + "Got a connected cell to %s with unsupported address family." + " Closing.", fmt_addr(&addr)); connection_edge_end(conn, END_STREAM_REASON_TORPROTOCOL); connection_mark_unattached_ap(entry_conn, END_STREAM_REASON_TORPROTOCOL); return 0; } - if (rh->length >= 8) - ttl = (int)ntohl(get_uint32(cell->payload+RELAY_HEADER_SIZE+4)); - else - ttl = -1; + client_dns_set_addressmap(TO_ORIGIN_CIRCUIT(circ), - entry_conn->socks_request->address, addr, + entry_conn->socks_request->address, &addr, entry_conn->chosen_exit_name, ttl); - remap_event_helper(entry_conn, addr); + remap_event_helper(entry_conn, &addr); } circuit_log_path(LOG_INFO,LD_APP,TO_ORIGIN_CIRCUIT(circ)); /* don't send a socks reply to transparent conns */ @@ -994,8 +1062,14 @@ connection_edge_process_relay_cell_not_open( ttl, -1); if (answer_type == RESOLVED_TYPE_IPV4 && answer_len == 4) { - uint32_t addr = ntohl(get_uint32(cell->payload+RELAY_HEADER_SIZE+2)); - remap_event_helper(entry_conn, addr); + tor_addr_t addr; + tor_addr_from_ipv4n(&addr, get_uint32(cell->payload+RELAY_HEADER_SIZE+2)); + remap_event_helper(entry_conn, &addr); + } else if (answer_type == RESOLVED_TYPE_IPV6 && answer_len == 16) { + tor_addr_t addr; + tor_addr_from_ipv6_bytes(&addr, + (char*)(cell->payload+RELAY_HEADER_SIZE+2)); + remap_event_helper(entry_conn, &addr); } connection_mark_unattached_ap(entry_conn, END_STREAM_REASON_DONE | diff --git a/src/or/relay.h b/src/or/relay.h index 0f7b45f..57400fd 100644 --- a/src/or/relay.h +++ b/src/or/relay.h @@ -68,6 +68,8 @@ void circuit_clear_cell_queue(circuit_t *circ, channel_t *chan); #ifdef RELAY_PRIVATE int relay_crypt(circuit_t *circ, cell_t *cell, cell_direction_t cell_direction, crypt_path_t **layer_hint, char *recognized); +int connected_cell_parse(const relay_header_t *rh, const cell_t *cell, + tor_addr_t *addr_out, int *ttl_out); #endif #endif diff --git a/src/test/test_cell_formats.c b/src/test/test_cell_formats.c index 2199a05..3fac745 100644 --- a/src/test/test_cell_formats.c +++ b/src/test/test_cell_formats.c @@ -6,6 +6,7 @@ #include "orconfig.h" #define CONNECTION_EDGE_PRIVATE +#define RELAY_PRIVATE #include "or.h" #include "connection_edge.h" #include "relay.h" @@ -223,12 +224,125 @@ test_cfmt_begin_cells(void *arg) tor_free(bcell.address); } +static void +test_cfmt_connected_cells(void *arg) +{ + relay_header_t rh; + cell_t cell; + tor_addr_t addr; + int ttl, r; + (void)arg; + + /* Let's try an oldschool one with nothing in it. */ + make_relay_cell(&cell, RELAY_COMMAND_CONNECTED, "", 0); + relay_header_unpack(&rh, cell.payload); + r = connected_cell_parse(&rh, &cell, &addr, &ttl); + tt_int_op(r, ==, 0); + tt_int_op(tor_addr_family(&addr), ==, AF_UNSPEC); + tt_int_op(ttl, ==, -1); + + /* A slightly less oldschool one: only an IPv4 address */ + make_relay_cell(&cell, RELAY_COMMAND_CONNECTED, "\x20\x30\x40\x50", 4); + relay_header_unpack(&rh, cell.payload); + r = connected_cell_parse(&rh, &cell, &addr, &ttl); + tt_int_op(r, ==, 0); + tt_int_op(tor_addr_family(&addr), ==, AF_INET); + tt_str_op(fmt_addr(&addr), ==, "32.48.64.80"); + tt_int_op(ttl, ==, -1); + + /* Bogus but understandable: truncated TTL */ + make_relay_cell(&cell, RELAY_COMMAND_CONNECTED, "\x11\x12\x13\x14\x15", 5); + relay_header_unpack(&rh, cell.payload); + r = connected_cell_parse(&rh, &cell, &addr, &ttl); + tt_int_op(r, ==, 0); + tt_int_op(tor_addr_family(&addr), ==, AF_INET); + tt_str_op(fmt_addr(&addr), ==, "17.18.19.20"); + tt_int_op(ttl, ==, -1); + + /* Regular IPv4 one: address and TTL */ + make_relay_cell(&cell, RELAY_COMMAND_CONNECTED, + "\x02\x03\x04\x05\x00\x00\x0e\x10", 8); + relay_header_unpack(&rh, cell.payload); + r = connected_cell_parse(&rh, &cell, &addr, &ttl); + tt_int_op(r, ==, 0); + tt_int_op(tor_addr_family(&addr), ==, AF_INET); + tt_str_op(fmt_addr(&addr), ==, "2.3.4.5"); + tt_int_op(ttl, ==, 3600); + + /* IPv4 with too-big TTL */ + make_relay_cell(&cell, RELAY_COMMAND_CONNECTED, + "\x02\x03\x04\x05\xf0\x00\x00\x00", 8); + relay_header_unpack(&rh, cell.payload); + r = connected_cell_parse(&rh, &cell, &addr, &ttl); + tt_int_op(r, ==, 0); + tt_int_op(tor_addr_family(&addr), ==, AF_INET); + tt_str_op(fmt_addr(&addr), ==, "2.3.4.5"); + tt_int_op(ttl, ==, -1); + + /* IPv6 (ttl is mandatory) */ + make_relay_cell(&cell, RELAY_COMMAND_CONNECTED, + "\x00\x00\x00\x00\x06" + "\x26\x07\xf8\xb0\x40\x0c\x0c\x02" + "\x00\x00\x00\x00\x00\x00\x00\x68" + "\x00\x00\x02\x58", 25); + relay_header_unpack(&rh, cell.payload); + r = connected_cell_parse(&rh, &cell, &addr, &ttl); + tt_int_op(r, ==, 0); + tt_int_op(tor_addr_family(&addr), ==, AF_INET6); + tt_str_op(fmt_addr(&addr), ==, "2607:f8b0:400c:c02::68"); + tt_int_op(ttl, ==, 600); + + /* IPv6 (ttl too big) */ + make_relay_cell(&cell, RELAY_COMMAND_CONNECTED, + "\x00\x00\x00\x00\x06" + "\x26\x07\xf8\xb0\x40\x0c\x0c\x02" + "\x00\x00\x00\x00\x00\x00\x00\x68" + "\x90\x00\x02\x58", 25); + relay_header_unpack(&rh, cell.payload); + r = connected_cell_parse(&rh, &cell, &addr, &ttl); + tt_int_op(r, ==, 0); + tt_int_op(tor_addr_family(&addr), ==, AF_INET6); + tt_str_op(fmt_addr(&addr), ==, "2607:f8b0:400c:c02::68"); + tt_int_op(ttl, ==, -1); + + /* Bogus size: 3. */ + make_relay_cell(&cell, RELAY_COMMAND_CONNECTED, + "\x00\x01\x02", 3); + relay_header_unpack(&rh, cell.payload); + r = connected_cell_parse(&rh, &cell, &addr, &ttl); + tt_int_op(r, ==, -1); + + /* Bogus family: 7. */ + make_relay_cell(&cell, RELAY_COMMAND_CONNECTED, + "\x00\x00\x00\x00\x07" + "\x26\x07\xf8\xb0\x40\x0c\x0c\x02" + "\x00\x00\x00\x00\x00\x00\x00\x68" + "\x90\x00\x02\x58", 25); + relay_header_unpack(&rh, cell.payload); + r = connected_cell_parse(&rh, &cell, &addr, &ttl); + tt_int_op(r, ==, -1); + + /* Truncated IPv6. */ + make_relay_cell(&cell, RELAY_COMMAND_CONNECTED, + "\x00\x00\x00\x00\x06" + "\x26\x07\xf8\xb0\x40\x0c\x0c\x02" + "\x00\x00\x00\x00\x00\x00\x00\x68" + "\x00\x00\x02", 24); + relay_header_unpack(&rh, cell.payload); + r = connected_cell_parse(&rh, &cell, &addr, &ttl); + tt_int_op(r, ==, -1); + + done: + ; +} + #define TEST(name, flags) \ { #name, test_cfmt_ ## name, flags, 0, NULL } struct testcase_t cell_format_tests[] = { TEST(relay_header, 0), TEST(begin_cells, 0), + TEST(connected_cells, 0), END_OF_TESTCASES };

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tor-commits November 2012