commit d43ba536df1b7a2433b4e1f7a2faa5a089b570c5 Author: Andrea Shepard <andrea@persephoneslair.org> Date: Fri Jun 15 20:19:02 2012 -0700 Clean up keys on stack in rend_service_introduce() --- src/or/rendservice.c | 40 +++++++++++++++++++++++++--------------- 1 files changed, 25 insertions(+), 15 deletions(-) diff --git a/src/or/rendservice.c b/src/or/rendservice.c index 2713596..85e8500 100644 --- a/src/or/rendservice.c +++ b/src/or/rendservice.c @@ -1055,6 +1055,7 @@ int rend_service_introduce(origin_circuit_t *circuit, const uint8_t *request, size_t request_len) { + int status = 0; char *ptr, *r_cookie; extend_info_t *extend_info = NULL; char buf[RELAY_PAYLOAD_SIZE]; @@ -1085,7 +1086,7 @@ rend_service_introduce(origin_circuit_t *circuit, const uint8_t *request, log_warn(LD_PROTOCOL, "Got an INTRODUCE2 over a non-introduction circuit %d.", circuit->_base.n_circ_id); - return -1; + goto err; } #ifndef NON_ANONYMOUS_MODE_ENABLED @@ -1103,7 +1104,7 @@ rend_service_introduce(origin_circuit_t *circuit, const uint8_t *request, DH_KEY_LEN+42) { log_warn(LD_PROTOCOL, "Got a truncated INTRODUCE2 cell on circ %d.", circuit->_base.n_circ_id); - return -1; + goto err; } /* look up service depending on circuit. */ @@ -1113,7 +1114,7 @@ rend_service_introduce(origin_circuit_t *circuit, const uint8_t *request, log_warn(LD_BUG, "Internal error: Got an INTRODUCE2 cell on an intro " "circ for an unrecognized service %s.", escaped(serviceid)); - return -1; + goto err; } /* use intro key instead of service key. */ @@ -1126,14 +1127,14 @@ rend_service_introduce(origin_circuit_t *circuit, const uint8_t *request, (char*)request, REND_SERVICE_ID_LEN); log_warn(LD_REND, "Got an INTRODUCE2 cell for the wrong service (%s).", escaped(serviceid)); - return -1; + goto err; } keylen = crypto_pk_keysize(intro_key); if (request_len < keylen+DIGEST_LEN) { log_warn(LD_PROTOCOL, "PK-encrypted portion of INTRODUCE2 cell was truncated."); - return -1; + goto err; } intro_point = find_intro_point(circuit); @@ -1141,7 +1142,7 @@ rend_service_introduce(origin_circuit_t *circuit, const uint8_t *request, log_warn(LD_BUG, "Internal error: Got an INTRODUCE2 cell on an intro circ " "(for service %s) with no corresponding rend_intro_point_t.", escaped(serviceid)); - return -1; + goto err; } if (!service->accepted_intro_dh_parts) @@ -1160,7 +1161,7 @@ rend_service_introduce(origin_circuit_t *circuit, const uint8_t *request, log_warn(LD_REND, "Possible replay detected! We received an " "INTRODUCE2 cell with same PK-encrypted part %d seconds ago. " "Dropping cell.", (int)(now-*access_time)); - return -1; + goto err; } access_time = tor_malloc(sizeof(time_t)); *access_time = now; @@ -1176,7 +1177,7 @@ rend_service_introduce(origin_circuit_t *circuit, const uint8_t *request, PK_PKCS1_OAEP_PADDING,1); if (r<0) { log_warn(LD_PROTOCOL, "Couldn't decrypt INTRODUCE2 cell."); - return -1; + goto err; } len = r; if (*buf == 3) { @@ -1191,7 +1192,7 @@ rend_service_introduce(origin_circuit_t *circuit, const uint8_t *request, if (auth_len != REND_DESC_COOKIE_LEN) { log_info(LD_REND, "Wrong auth data size %d, should be %d.", (int)auth_len, REND_DESC_COOKIE_LEN); - return -1; + goto err; } memcpy(auth_data, buf+4, sizeof(auth_data)); v3_shift += 2+REND_DESC_COOKIE_LEN; @@ -1252,12 +1253,12 @@ rend_service_introduce(origin_circuit_t *circuit, const uint8_t *request, if (!ptr || ptr == rp_nickname) { log_warn(LD_PROTOCOL, "Couldn't find a nul-padded nickname in INTRODUCE2 cell."); - return -1; + goto err; } if ((version == 0 && !is_legal_nickname(rp_nickname)) || (version == 1 && !is_legal_nickname_or_hexdigest(rp_nickname))) { log_warn(LD_PROTOCOL, "Bad nickname in INTRODUCE2 cell."); - return -1; + goto err; } /* Okay, now we know that a nickname is at the start of the buffer. */ ptr = rp_nickname+nickname_field_len; @@ -1421,15 +1422,24 @@ rend_service_introduce(origin_circuit_t *circuit, const uint8_t *request, memcpy(cpath->handshake_digest, keys, DIGEST_LEN); if (extend_info) extend_info_free(extend_info); - memset(keys, 0, sizeof(keys)); - return 0; + goto done; + err: - memset(keys, 0, sizeof(keys)); + status = -1; if (dh) crypto_dh_free(dh); if (launched) circuit_mark_for_close(TO_CIRCUIT(launched), reason); if (extend_info) extend_info_free(extend_info); - return -1; + done: + memset(keys, 0, sizeof(keys)); + memset(buf, 0, sizeof(buf)); + memset(serviceid, 0, sizeof(serviceid)); + memset(hexcookie, 0, sizeof(hexcookie)); + memset(intro_key_digest, 0, sizeof(intro_key_digest)); + memset(auth_data, 0, sizeof(auth_data)); + memset(diffie_hellman_hash, 0, sizeof(diffie_hellman_hash)); + + return status; } /** Called when we fail building a rendezvous circuit at some point other