/* * SPDX-License-Identifier: BSD-3-Clause * * https://opensource.org/license/bsd-3-clause * * Copyright (C) 2011, 2012, 2013 Citrix Systems * * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the project nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include "ns_turn_msg.h" #include "ns_turn_msg_addr.h" ///////////// Security functions implementation from ns_turn_msg.h /////////// #include "ns_turn_openssl.h" #include "ns_turn_utils.h" /////////// #include // for tolower #include #include // for fprintf, printf, stderr, snprintf #include #include // for memcpy, strlen, memset, strncpy, strcmp /////////// #define FINGERPRINT_XOR 0x5354554e /////////// int stun_method_str(uint16_t method, char *smethod) { int ret = 0; const char *s = "UNKNOWN"; switch (method) { case STUN_METHOD_BINDING: s = "BINDING"; break; case STUN_METHOD_ALLOCATE: s = "ALLOCATE"; break; case STUN_METHOD_REFRESH: s = "REFRESH"; break; case STUN_METHOD_SEND: s = "SEND"; break; case STUN_METHOD_DATA: s = "DATA"; break; case STUN_METHOD_CREATE_PERMISSION: s = "CREATE_PERMISSION"; break; case STUN_METHOD_CHANNEL_BIND: s = "CHANNEL_BIND"; break; case STUN_METHOD_CONNECT: s = "CONNECT"; break; case STUN_METHOD_CONNECTION_BIND: s = "CONNECTION_BIND"; break; case STUN_METHOD_CONNECTION_ATTEMPT: s = "CONNECTION_ATTEMPT"; break; default: ret = -1; }; if (smethod) { strcpy(smethod, s); } return ret; } long turn_random_number(void) { long ret = 0; if (!RAND_bytes((unsigned char *)&ret, sizeof(ret))) #if defined(WINDOWS) ret = rand(); #else ret = random(); #endif return ret; } static void generate_random_nonce(unsigned char *nonce, size_t sz) { if (!RAND_bytes(nonce, (int)sz)) { for (size_t i = 0; i < sz; ++i) { nonce[i] = (unsigned char)turn_random_number(); } } } static void turn_random_tid_size(void *id) { uint32_t *ar = (uint32_t *)id; if (!RAND_bytes((unsigned char *)ar, 12)) { for (size_t i = 0; i < 3; ++i) { ar[i] = (uint32_t)turn_random_number(); } } } bool stun_calculate_hmac(const uint8_t *buf, size_t len, const uint8_t *key, size_t keylen, uint8_t *hmac, unsigned int *hmac_len, SHATYPE shatype) { ERR_clear_error(); UNUSED_ARG(shatype); if (shatype == SHATYPE_SHA256) { #if !defined(OPENSSL_NO_SHA256) && defined(SHA256_DIGEST_LENGTH) if (!HMAC(EVP_sha256(), key, (int)keylen, buf, len, hmac, hmac_len)) { return false; } #else fprintf(stderr, "SHA256 is not supported\n"); return false; #endif } else if (shatype == SHATYPE_SHA384) { #if !defined(OPENSSL_NO_SHA384) && defined(SHA384_DIGEST_LENGTH) if (!HMAC(EVP_sha384(), key, (int)keylen, buf, len, hmac, hmac_len)) { return false; } #else fprintf(stderr, "SHA384 is not supported\n"); return false; #endif } else if (shatype == SHATYPE_SHA512) { #if !defined(OPENSSL_NO_SHA512) && defined(SHA512_DIGEST_LENGTH) if (!HMAC(EVP_sha512(), key, (int)keylen, buf, len, hmac, hmac_len)) { return false; } #else fprintf(stderr, "SHA512 is not supported\n"); return false; #endif } else if (!HMAC(EVP_sha1(), key, (int)keylen, buf, len, hmac, hmac_len)) { return false; } return true; } bool stun_produce_integrity_key_str(const uint8_t *uname, const uint8_t *realm, const uint8_t *upwd, hmackey_t key, SHATYPE shatype) { bool ret; ERR_clear_error(); UNUSED_ARG(shatype); size_t ulen = strlen((const char *)uname); size_t rlen = strlen((const char *)realm); size_t plen = strlen((const char *)upwd); size_t sz = ulen + 1 + rlen + 1 + plen + 1 + 10; size_t strl = ulen + 1 + rlen + 1 + plen; uint8_t *str = (uint8_t *)malloc(sz + 1); strncpy((char *)str, (const char *)uname, sz); str[ulen] = ':'; strncpy((char *)str + ulen + 1, (const char *)realm, sz - ulen - 1); str[ulen + 1 + rlen] = ':'; strncpy((char *)str + ulen + 1 + rlen + 1, (const char *)upwd, sz - ulen - 1 - rlen - 1); str[strl] = 0; if (shatype == SHATYPE_SHA256) { #if !defined(OPENSSL_NO_SHA256) && defined(SHA256_DIGEST_LENGTH) unsigned int keylen = 0; EVP_MD_CTX *ctx = EVP_MD_CTX_new(); EVP_DigestInit(ctx, EVP_sha256()); EVP_DigestUpdate(ctx, str, strl); EVP_DigestFinal(ctx, key, &keylen); EVP_MD_CTX_free(ctx); ret = true; #else fprintf(stderr, "SHA256 is not supported\n"); ret = false; #endif } else if (shatype == SHATYPE_SHA384) { #if !defined(OPENSSL_NO_SHA384) && defined(SHA384_DIGEST_LENGTH) unsigned int keylen = 0; EVP_MD_CTX *ctx = EVP_MD_CTX_new(); EVP_DigestInit(ctx, EVP_sha384()); EVP_DigestUpdate(ctx, str, strl); EVP_DigestFinal(ctx, key, &keylen); EVP_MD_CTX_free(ctx); ret = true; #else fprintf(stderr, "SHA384 is not supported\n"); ret = false; #endif } else if (shatype == SHATYPE_SHA512) { #if !defined(OPENSSL_NO_SHA512) && defined(SHA512_DIGEST_LENGTH) unsigned int keylen = 0; EVP_MD_CTX *ctx = EVP_MD_CTX_new(); EVP_DigestInit(ctx, EVP_sha512()); EVP_DigestUpdate(ctx, str, strl); EVP_DigestFinal(ctx, key, &keylen); EVP_MD_CTX_free(ctx); ret = true; #else fprintf(stderr, "SHA512 is not supported\n"); ret = false; #endif } else { #if OPENSSL_VERSION_NUMBER >= 0x30000000L unsigned int keylen = 0; EVP_MD_CTX *ctx = EVP_MD_CTX_new(); if (EVP_default_properties_is_fips_enabled(NULL)) { EVP_default_properties_enable_fips(NULL, 0); } EVP_DigestInit_ex(ctx, EVP_md5(), NULL); EVP_DigestUpdate(ctx, str, strl); EVP_DigestFinal(ctx, key, &keylen); EVP_MD_CTX_free(ctx); #else // OPENSSL_VERSION_NUMBER < 0x30000000L unsigned int keylen = 0; EVP_MD_CTX *ctx = EVP_MD_CTX_new(); #if defined EVP_MD_CTX_FLAG_NON_FIPS_ALLOW && !defined(LIBRESSL_VERSION_NUMBER) if (FIPS_mode()) { EVP_MD_CTX_set_flags(ctx, EVP_MD_CTX_FLAG_NON_FIPS_ALLOW); } #endif EVP_DigestInit_ex(ctx, EVP_md5(), NULL); EVP_DigestUpdate(ctx, str, strl); EVP_DigestFinal(ctx, key, &keylen); EVP_MD_CTX_free(ctx); #endif // OPENSSL_VERSION_NUMBER >= 0X30000000L ret = true; } free(str); return ret; } #define PWD_SALT_SIZE (8) static void readable_string(unsigned char *orig, unsigned char *out, size_t sz) { out[0] = '\0'; for (size_t i = 0; i < sz; ++i) { snprintf((char *)(out + (i * 2)), 3, "%02x", (unsigned int)orig[i]); } out[sz * 2] = 0; } static void generate_enc_password(const char *pwd, char *result, const unsigned char *orig_salt) { unsigned char salt[PWD_SALT_SIZE + 1]; if (!orig_salt) { generate_random_nonce(salt, PWD_SALT_SIZE); } else { memcpy(salt, orig_salt, PWD_SALT_SIZE); salt[PWD_SALT_SIZE] = 0; } unsigned char rsalt[PWD_SALT_SIZE * 2 + 1]; readable_string(salt, rsalt, PWD_SALT_SIZE); result[0] = '$'; result[1] = '5'; result[2] = '$'; memcpy(result + 3, (char *)rsalt, PWD_SALT_SIZE + PWD_SALT_SIZE); result[3 + PWD_SALT_SIZE + PWD_SALT_SIZE] = '$'; unsigned char *out = (unsigned char *)(result + 3 + PWD_SALT_SIZE + PWD_SALT_SIZE + 1); { EVP_MD_CTX *ctx = EVP_MD_CTX_new(); #if !defined(OPENSSL_NO_SHA256) && defined(SHA256_DIGEST_LENGTH) EVP_DigestInit(ctx, EVP_sha256()); #else EVP_DigestInit(ctx, EVP_sha1()); #endif EVP_DigestUpdate(ctx, salt, PWD_SALT_SIZE); EVP_DigestUpdate(ctx, pwd, strlen(pwd)); { unsigned char hash[129]; unsigned int keylen = 0; EVP_DigestFinal(ctx, hash, &keylen); readable_string(hash, out, keylen); } EVP_MD_CTX_free(ctx); } } void generate_new_enc_password(const char *pwd, char *result) { generate_enc_password(pwd, result, NULL); } static bool encrypted_password(const char *pin, unsigned char *salt) { static const size_t min_len = 3 + PWD_SALT_SIZE + PWD_SALT_SIZE + 1 + 32; if (strlen(pin) >= min_len) { if ((pin[0] == '$') && (pin[1] == '5') && (pin[2] == '$') && (pin[3 + PWD_SALT_SIZE + PWD_SALT_SIZE] == '$')) { for (size_t i = 0; i < PWD_SALT_SIZE; ++i) { const char *c = pin + 3 + i + i; char sc[3]; sc[0] = c[0]; sc[1] = c[1]; sc[2] = 0; salt[i] = (unsigned char)strtoul(sc, NULL, 16); } return true; } } return false; } bool check_password_equal(const char *pin, const char *pwd) { unsigned char salt[PWD_SALT_SIZE]; if (!encrypted_password(pwd, salt)) { return 0 == strcmp(pin, pwd); } char enc_pin[257]; generate_enc_password(pin, enc_pin, salt); return 0 == strcmp(enc_pin, pwd); } ///////////////////////////////////////////////////////////////// static uint32_t ns_crc32(const uint8_t *buffer, uint32_t len); ///////////////////////////////////////////////////////////////// int stun_get_command_message_len_str(const uint8_t *buf, size_t len) { if (len < STUN_HEADER_LENGTH) { return -1; } /* Validate the size the buffer claims to be */ size_t bufLen = (size_t)(nswap16(((const uint16_t *)(buf))[1]) + STUN_HEADER_LENGTH); if (bufLen > len) { return -1; } return bufLen; } static bool stun_set_command_message_len_str(uint8_t *buf, int len) { if (len < STUN_HEADER_LENGTH) { return false; } ((uint16_t *)buf)[1] = nswap16((uint16_t)(len - STUN_HEADER_LENGTH)); return true; } /////////// Low-level binary ////////////////////////////////////////////// uint16_t stun_make_type(uint16_t method) { method = method & 0x0FFF; return ((method & 0x000F) | ((method & 0x0070) << 1) | ((method & 0x0380) << 2) | ((method & 0x0C00) << 2)); } uint16_t stun_get_method_str(const uint8_t *buf, size_t len) { if (!buf || len < 2) { return (uint16_t)-1; } uint16_t tt = nswap16(((const uint16_t *)buf)[0]); return (tt & 0x000F) | ((tt & 0x00E0) >> 1) | ((tt & 0x0E00) >> 2) | ((tt & 0x3000) >> 2); } uint16_t stun_get_msg_type_str(const uint8_t *buf, size_t len) { if (!buf || len < 2) { return (uint16_t)-1; } return ((nswap16(((const uint16_t *)buf)[0])) & 0x3FFF); } bool is_channel_msg_str(const uint8_t *buf, size_t blen) { return (buf && blen >= 4 && STUN_VALID_CHANNEL(nswap16(((const uint16_t *)buf)[0]))); } /////////////// message types ///////////////////////////////// bool stun_is_command_message_str(const uint8_t *buf, size_t blen) { if (buf && blen >= STUN_HEADER_LENGTH) { if (!STUN_VALID_CHANNEL(nswap16(((const uint16_t *)buf)[0]))) { if ((((uint8_t)buf[0]) & ((uint8_t)(0xC0))) == 0) { if (nswap32(((const uint32_t *)(buf))[1]) == STUN_MAGIC_COOKIE) { uint16_t len = nswap16(((const uint16_t *)(buf))[1]); if ((len & 0x0003) == 0) { if ((size_t)(len + STUN_HEADER_LENGTH) == blen) { return true; } } } } } } return false; } bool old_stun_is_command_message_str(const uint8_t *buf, size_t blen, uint32_t *cookie) { if (buf && blen >= STUN_HEADER_LENGTH) { if (!STUN_VALID_CHANNEL(nswap16(((const uint16_t *)buf)[0]))) { if ((((uint8_t)buf[0]) & ((uint8_t)(0xC0))) == 0) { if (nswap32(((const uint32_t *)(buf))[1]) != STUN_MAGIC_COOKIE) { uint16_t len = nswap16(((const uint16_t *)(buf))[1]); if ((len & 0x0003) == 0) { if ((size_t)(len + STUN_HEADER_LENGTH) == blen) { *cookie = nswap32(((const uint32_t *)(buf))[1]); return true; } } } } } } return false; } bool stun_is_command_message_full_check_str(const uint8_t *buf, size_t blen, int must_check_fingerprint, int *fingerprint_present) { if (!stun_is_command_message_str(buf, blen)) { return false; } stun_attr_ref sar = stun_attr_get_first_by_type_str(buf, blen, STUN_ATTRIBUTE_FINGERPRINT); if (!sar) { if (fingerprint_present) { *fingerprint_present = 0; } if (stun_get_method_str(buf, blen) == STUN_METHOD_BINDING) { return true; } return !must_check_fingerprint; } if (stun_attr_get_len(sar) != 4) { return false; } const uint32_t *fingerprint = (const uint32_t *)stun_attr_get_value(sar); if (!fingerprint) { return !must_check_fingerprint; } uint32_t crc32len = (uint32_t)((((const uint8_t *)fingerprint) - buf) - 4); bool ret = (*fingerprint == nswap32(ns_crc32(buf, crc32len) ^ ((uint32_t)FINGERPRINT_XOR))); if (ret && fingerprint_present) { *fingerprint_present = ret; } return ret; } bool stun_is_request_str(const uint8_t *buf, size_t len) { if (is_channel_msg_str(buf, len)) { return false; } return IS_STUN_REQUEST(stun_get_msg_type_str(buf, len)); } bool stun_is_success_response_str(const uint8_t *buf, size_t len) { if (is_channel_msg_str(buf, len)) { return false; } return IS_STUN_SUCCESS_RESP(stun_get_msg_type_str(buf, len)); } bool stun_is_error_response_str(const uint8_t *buf, size_t len, int *err_code, uint8_t *err_msg, size_t err_msg_size) { if (is_channel_msg_str(buf, len)) { return false; } if (IS_STUN_ERR_RESP(stun_get_msg_type_str(buf, len))) { if (err_code) { stun_attr_ref sar = stun_attr_get_first_by_type_str(buf, len, STUN_ATTRIBUTE_ERROR_CODE); if (sar) { if (stun_attr_get_len(sar) >= 4) { const uint8_t *val = (const uint8_t *)stun_attr_get_value(sar); *err_code = (int)(val[2] * 100 + val[3]); if (err_msg && err_msg_size > 0) { err_msg[0] = 0; if (stun_attr_get_len(sar) > 4) { size_t msg_len = stun_attr_get_len(sar) - 4; if (msg_len > (err_msg_size - 1)) { msg_len = err_msg_size - 1; } memcpy(err_msg, val + 4, msg_len); err_msg[msg_len] = 0; } } } } } return true; } return false; } bool stun_is_challenge_response_str(const uint8_t *buf, size_t len, int *err_code, uint8_t *err_msg, size_t err_msg_size, uint8_t *realm, uint8_t *nonce, uint8_t *server_name, bool *oauth) { bool ret = stun_is_error_response_str(buf, len, err_code, err_msg, err_msg_size); if (ret && (((*err_code) == 401) || ((*err_code) == 438))) { stun_attr_ref sar = stun_attr_get_first_by_type_str(buf, len, STUN_ATTRIBUTE_REALM); if (sar) { bool found_oauth = false; const uint8_t *value = stun_attr_get_value(sar); if (value) { size_t vlen = (size_t)stun_attr_get_len(sar); vlen = min(vlen, (size_t)STUN_MAX_REALM_SIZE); memcpy(realm, value, vlen); realm[vlen] = 0; { sar = stun_attr_get_first_by_type_str(buf, len, STUN_ATTRIBUTE_THIRD_PARTY_AUTHORIZATION); if (sar) { value = stun_attr_get_value(sar); if (value) { vlen = (size_t)stun_attr_get_len(sar); vlen = min(vlen, (size_t)STUN_MAX_SERVER_NAME_SIZE); if (vlen > 0) { if (server_name) { memcpy(server_name, value, vlen); } found_oauth = true; } } } } sar = stun_attr_get_first_by_type_str(buf, len, STUN_ATTRIBUTE_NONCE); if (sar) { value = stun_attr_get_value(sar); if (value) { vlen = (size_t)stun_attr_get_len(sar); vlen = min(vlen, (size_t)STUN_MAX_NONCE_SIZE); memcpy(nonce, value, vlen); nonce[vlen] = 0; if (oauth) { *oauth = found_oauth; } return true; } } } } } return false; } bool stun_is_response_str(const uint8_t *buf, size_t len) { if (is_channel_msg_str(buf, len)) { return false; } if (IS_STUN_SUCCESS_RESP(stun_get_msg_type_str(buf, len))) { return true; } if (IS_STUN_ERR_RESP(stun_get_msg_type_str(buf, len))) { return true; } return false; } bool stun_is_indication_str(const uint8_t *buf, size_t len) { if (is_channel_msg_str(buf, len)) { return false; } return IS_STUN_INDICATION(stun_get_msg_type_str(buf, len)); } uint16_t stun_make_request(uint16_t method) { return GET_STUN_REQUEST(stun_make_type(method)); } uint16_t stun_make_indication(uint16_t method) { return GET_STUN_INDICATION(stun_make_type(method)); } uint16_t stun_make_success_response(uint16_t method) { return GET_STUN_SUCCESS_RESP(stun_make_type(method)); } uint16_t stun_make_error_response(uint16_t method) { return GET_STUN_ERR_RESP(stun_make_type(method)); } //////////////// INIT //////////////////////////////////////////// void stun_init_buffer_str(uint8_t *buf, size_t *len) { *len = STUN_HEADER_LENGTH; memset(buf, 0, *len); } void stun_init_command_str(uint16_t message_type, uint8_t *buf, size_t *len) { stun_init_buffer_str(buf, len); message_type &= (uint16_t)(0x3FFF); ((uint16_t *)buf)[0] = nswap16(message_type); ((uint16_t *)buf)[1] = 0; ((uint32_t *)buf)[1] = nswap32(STUN_MAGIC_COOKIE); stun_tid_generate_in_message_str(buf, NULL); } void old_stun_init_command_str(uint16_t message_type, uint8_t *buf, size_t *len, uint32_t cookie) { stun_init_buffer_str(buf, len); message_type &= (uint16_t)(0x3FFF); ((uint16_t *)buf)[0] = nswap16(message_type); ((uint16_t *)buf)[1] = 0; ((uint32_t *)buf)[1] = nswap32(cookie); stun_tid_generate_in_message_str(buf, NULL); } void stun_init_request_str(uint16_t method, uint8_t *buf, size_t *len) { stun_init_command_str(stun_make_request(method), buf, len); } void stun_init_indication_str(uint16_t method, uint8_t *buf, size_t *len) { stun_init_command_str(stun_make_indication(method), buf, len); } void stun_init_success_response_str(uint16_t method, uint8_t *buf, size_t *len, stun_tid *id) { stun_init_command_str(stun_make_success_response(method), buf, len); if (id) { stun_tid_message_cpy(buf, id); } } void old_stun_init_success_response_str(uint16_t method, uint8_t *buf, size_t *len, stun_tid *id, uint32_t cookie) { old_stun_init_command_str(stun_make_success_response(method), buf, len, cookie); if (id) { stun_tid_message_cpy(buf, id); } } const uint8_t *get_default_reason(int error_code) { const char *reason = "Unknown error"; switch (error_code) { case 300: reason = "Try Alternate"; break; case 400: reason = "Bad Request"; break; case 401: reason = "Unauthorized"; break; case 403: reason = "Forbidden"; break; case 404: reason = "Not Found"; break; case 420: reason = "Unknown Attribute"; break; case 437: reason = "Allocation Mismatch"; break; case 438: reason = "Stale Nonce"; break; case 440: reason = "Address Family not Supported"; break; case 441: reason = "Wrong Credentials"; break; case 442: reason = "Unsupported Transport Protocol"; break; case 443: reason = "Peer Address Family Mismatch"; break; case 446: reason = "Connection Already Exists"; break; case 447: reason = "Connection Timeout or Failure"; break; case 486: reason = "Allocation Quota Reached"; break; case 487: reason = "Role Conflict"; break; case 500: reason = "Server Error"; break; case 508: reason = "Insufficient Capacity"; break; default:; }; return (const uint8_t *)reason; } static void stun_init_error_response_common_str(uint8_t *buf, size_t *len, uint16_t error_code, const uint8_t *reason, stun_tid *id) { if (!reason || !strcmp((const char *)reason, "Unknown error")) { reason = get_default_reason(error_code); } uint8_t avalue[513]; avalue[0] = 0; avalue[1] = 0; avalue[2] = (uint8_t)(error_code / 100); avalue[3] = (uint8_t)(error_code % 100); strncpy((char *)(avalue + 4), (const char *)reason, sizeof(avalue) - 4); avalue[sizeof(avalue) - 1] = 0; int alen = 4 + (int)strlen((const char *)(avalue + 4)); //"Manual" padding for compatibility with classic old stun: { int rem = alen % 4; if (rem) { alen += (4 - rem); } } stun_attr_add_str(buf, len, STUN_ATTRIBUTE_ERROR_CODE, (uint8_t *)avalue, alen); if (id) { stun_tid_message_cpy(buf, id); } } void old_stun_init_error_response_str(uint16_t method, uint8_t *buf, size_t *len, uint16_t error_code, const uint8_t *reason, stun_tid *id, uint32_t cookie) { old_stun_init_command_str(stun_make_error_response(method), buf, len, cookie); stun_init_error_response_common_str(buf, len, error_code, reason, id); } void stun_init_error_response_str(uint16_t method, uint8_t *buf, size_t *len, uint16_t error_code, const uint8_t *reason, stun_tid *id) { stun_init_command_str(stun_make_error_response(method), buf, len); stun_init_error_response_common_str(buf, len, error_code, reason, id); } /////////// CHANNEL //////////////////////////////////////////////// bool stun_init_channel_message_str(uint16_t chnumber, uint8_t *buf, size_t *len, int length, bool do_padding) { uint16_t rlen = (uint16_t)length; if (length < 0 || (MAX_STUN_MESSAGE_SIZE < (4 + length))) { return false; } ((uint16_t *)(buf))[0] = nswap16(chnumber); ((uint16_t *)(buf))[1] = nswap16((uint16_t)length); if (do_padding && (rlen & 0x0003)) { rlen = ((rlen >> 2) + 1) << 2; } *len = 4 + rlen; return true; } bool stun_is_channel_message_str(const uint8_t *buf, size_t *blen, uint16_t *chnumber, bool mandatory_padding) { uint16_t datalen_header; uint16_t datalen_actual; if (!blen || (*blen < 4)) { return false; } uint16_t chn = nswap16(((const uint16_t *)(buf))[0]); if (!STUN_VALID_CHANNEL(chn)) { return false; } if (*blen > (uint16_t)-1) { *blen = (uint16_t)-1; } datalen_actual = (uint16_t)(*blen) - 4; datalen_header = ((const uint16_t *)buf)[1]; datalen_header = nswap16(datalen_header); if (datalen_header > datalen_actual) { return false; } if (datalen_header != datalen_actual) { /* maybe there are padding bytes for 32-bit alignment. Mandatory for TCP. Optional for UDP */ if (datalen_actual & 0x0003) { if (mandatory_padding) { return false; } else if (datalen_header == 0) { return false; } else { uint16_t diff = datalen_actual - datalen_header; if (diff > 3) { return false; } } } } *blen = datalen_header + 4; if (chnumber) { *chnumber = chn; } return true; } ////////// STUN message /////////////////////////////// static inline bool sheadof(const char *head, const char *full, bool ignore_case) { while (*head) { if (*head != *full) { if (ignore_case && (tolower((int)*head) == tolower((int)*full))) { // OK } else { return false; } } ++head; ++full; } return true; } static inline const char *findstr(const char *hay, size_t slen, const char *needle, bool ignore_case) { const char *ret = NULL; if (hay && slen && needle) { size_t nlen = strlen(needle); if (nlen <= slen) { size_t smax = slen - nlen + 1; const char *sp = hay; for (size_t i = 0; i < smax; ++i) { if (sheadof(needle, sp + i, ignore_case)) { ret = sp + i; break; } } } } return ret; } int is_http(const char *s, size_t blen) { if (s && blen >= 12) { if ((strstr(s, "GET ") == s) || (strstr(s, "POST ") == s) || (strstr(s, "DELETE ") == s) || (strstr(s, "PUT ") == s)) { const char *sp = findstr(s + 4, blen - 4, " HTTP/", false); if (sp) { sp += 6; size_t diff_blen = sp - s; if (diff_blen + 4 <= blen) { sp = findstr(sp, blen - diff_blen, "\r\n\r\n", false); if (sp) { int ret_len = (int)(sp - s + 4); const char *clheader = "content-length: "; const char *cl = findstr(s, sp - s, clheader, true); if (cl) { unsigned long clen = strtoul(cl + strlen(clheader), NULL, 10); if (clen > 0 && clen < (0x0FFFFFFF)) { ret_len += (int)clen; } } return ret_len; } } } } } return 0; } int stun_get_message_len_str(uint8_t *buf, size_t blen, int padding, size_t *app_len) { if (buf && blen) { /* STUN request/response ? */ if (buf && blen >= STUN_HEADER_LENGTH) { if (!STUN_VALID_CHANNEL(nswap16(((const uint16_t *)buf)[0]))) { if ((((uint8_t)buf[0]) & ((uint8_t)(0xC0))) == 0) { if (nswap32(((const uint32_t *)(buf))[1]) == STUN_MAGIC_COOKIE) { uint16_t len = nswap16(((const uint16_t *)(buf))[1]); if ((len & 0x0003) == 0) { len += STUN_HEADER_LENGTH; if ((size_t)len <= blen) { *app_len = (size_t)len; return (int)len; } } } } } } // HTTP request ? { int http_len = is_http(((char *)buf), blen); if ((http_len > 0) && ((size_t)http_len <= blen)) { *app_len = (size_t)http_len; return http_len; } } /* STUN channel ? */ if (blen >= 4) { uint16_t chn = nswap16(((const uint16_t *)(buf))[0]); if (STUN_VALID_CHANNEL(chn)) { uint16_t bret = (4 + (nswap16(((const uint16_t *)(buf))[1]))); *app_len = bret; if (padding && (bret & 0x0003)) { bret = ((bret >> 2) + 1) << 2; } if (bret <= blen) { return bret; } } } } return -1; } ////////// ALLOCATE /////////////////////////////////// bool stun_set_allocate_request_str(uint8_t *buf, size_t *len, uint32_t lifetime, bool af4, bool af6, uint8_t transport, bool mobile, const char *rt, int ep) { stun_init_request_str(STUN_METHOD_ALLOCATE, buf, len); // REQUESTED-TRANSPORT { uint8_t field[4]; field[0] = transport; field[1] = 0; field[2] = 0; field[3] = 0; if (!stun_attr_add_str(buf, len, STUN_ATTRIBUTE_REQUESTED_TRANSPORT, field, sizeof(field))) { return false; } } // LIFETIME { if (lifetime < 1) { lifetime = STUN_DEFAULT_ALLOCATE_LIFETIME; } uint32_t field = nswap32(lifetime); if (!stun_attr_add_str(buf, len, STUN_ATTRIBUTE_LIFETIME, (uint8_t *)(&field), sizeof(field))) { return false; } } // MICE if (mobile) { if (!stun_attr_add_str(buf, len, STUN_ATTRIBUTE_MOBILITY_TICKET, (const uint8_t *)"", 0)) { return false; } } if (ep > -1) { uint8_t value = ep ? 0x80 : 0x00; if (!stun_attr_add_str(buf, len, STUN_ATTRIBUTE_EVEN_PORT, (const uint8_t *)&value, 1)) { return false; } } // RESERVATION-TOKEN, EVEN-PORT and DUAL-ALLOCATION are mutually exclusive: if (rt) { stun_attr_add_str(buf, len, STUN_ATTRIBUTE_RESERVATION_TOKEN, (const uint8_t *)rt, 8); } else { // ADRESS-FAMILY if (af4 && !af6) { uint8_t field[4]; field[0] = (uint8_t)STUN_ATTRIBUTE_REQUESTED_ADDRESS_FAMILY_VALUE_IPV4; field[1] = 0; field[2] = 0; field[3] = 0; if (!stun_attr_add_str(buf, len, STUN_ATTRIBUTE_REQUESTED_ADDRESS_FAMILY, field, sizeof(field))) { return false; } } if (af6 && !af4) { uint8_t field[4]; field[0] = (uint8_t)STUN_ATTRIBUTE_REQUESTED_ADDRESS_FAMILY_VALUE_IPV6; field[1] = 0; field[2] = 0; field[3] = 0; if (!stun_attr_add_str(buf, len, STUN_ATTRIBUTE_REQUESTED_ADDRESS_FAMILY, field, sizeof(field))) { return false; } } if (af4 && af6) { uint8_t field[4]; field[0] = (uint8_t)STUN_ATTRIBUTE_REQUESTED_ADDRESS_FAMILY_VALUE_IPV6; field[1] = 0; field[2] = 0; field[3] = 0; if (!stun_attr_add_str(buf, len, STUN_ATTRIBUTE_ADDITIONAL_ADDRESS_FAMILY, field, sizeof(field))) { return false; } } } return true; } bool stun_set_allocate_response_str(uint8_t *buf, size_t *len, stun_tid *tid, const ioa_addr *relayed_addr1, const ioa_addr *relayed_addr2, const ioa_addr *reflexive_addr, uint32_t lifetime, uint32_t max_lifetime, int error_code, const uint8_t *reason, uint64_t reservation_token, char *mobile_id) { if (!error_code) { stun_init_success_response_str(STUN_METHOD_ALLOCATE, buf, len, tid); if (relayed_addr1) { if (!stun_attr_add_addr_str(buf, len, STUN_ATTRIBUTE_XOR_RELAYED_ADDRESS, relayed_addr1)) { return false; } } if (relayed_addr2) { if (!stun_attr_add_addr_str(buf, len, STUN_ATTRIBUTE_XOR_RELAYED_ADDRESS, relayed_addr2)) { return false; } } if (reflexive_addr) { if (!stun_attr_add_addr_str(buf, len, STUN_ATTRIBUTE_XOR_MAPPED_ADDRESS, reflexive_addr)) { return false; } } if (reservation_token) { reservation_token = nswap64(reservation_token); stun_attr_add_str(buf, len, STUN_ATTRIBUTE_RESERVATION_TOKEN, (uint8_t *)(&reservation_token), 8); } { if (lifetime < 1) { lifetime = STUN_DEFAULT_ALLOCATE_LIFETIME; } else if (lifetime > max_lifetime) { lifetime = max_lifetime; } uint32_t field = nswap32(lifetime); if (!stun_attr_add_str(buf, len, STUN_ATTRIBUTE_LIFETIME, (uint8_t *)(&field), sizeof(field))) { return false; } } if (mobile_id && *mobile_id) { if (!stun_attr_add_str(buf, len, STUN_ATTRIBUTE_MOBILITY_TICKET, (uint8_t *)mobile_id, (int)strlen(mobile_id))) { return false; } } } else { stun_init_error_response_str(STUN_METHOD_ALLOCATE, buf, len, error_code, reason, tid); } return true; } /////////////// CHANNEL BIND /////////////////////////////////////// uint16_t stun_set_channel_bind_request_str(uint8_t *buf, size_t *len, const ioa_addr *peer_addr, uint16_t channel_number) { if (!STUN_VALID_CHANNEL(channel_number)) { channel_number = 0x4000 + ((uint16_t)(((uint32_t)turn_random_number()) % (0x7FFF - 0x4000 + 1))); } stun_init_request_str(STUN_METHOD_CHANNEL_BIND, buf, len); if (!stun_attr_add_channel_number_str(buf, len, channel_number)) { return 0; } if (!peer_addr) { ioa_addr ca; memset(&ca, 0, sizeof(ioa_addr)); if (!stun_attr_add_addr_str(buf, len, STUN_ATTRIBUTE_XOR_PEER_ADDRESS, &ca)) { return 0; } } else { if (!stun_attr_add_addr_str(buf, len, STUN_ATTRIBUTE_XOR_PEER_ADDRESS, peer_addr)) { return 0; } } return channel_number; } void stun_set_channel_bind_response_str(uint8_t *buf, size_t *len, stun_tid *tid, int error_code, const uint8_t *reason) { if (!error_code) { stun_init_success_response_str(STUN_METHOD_CHANNEL_BIND, buf, len, tid); } else { stun_init_error_response_str(STUN_METHOD_CHANNEL_BIND, buf, len, error_code, reason, tid); } } /////////////// BINDING /////////////////////////////////////// void stun_set_binding_request_str(uint8_t *buf, size_t *len) { stun_init_request_str(STUN_METHOD_BINDING, buf, len); } bool stun_set_binding_response_str(uint8_t *buf, size_t *len, stun_tid *tid, const ioa_addr *reflexive_addr, int error_code, const uint8_t *reason, uint32_t cookie, bool old_stun, bool stun_backward_compatibility) { if (!error_code) { if (!old_stun) { stun_init_success_response_str(STUN_METHOD_BINDING, buf, len, tid); } else { old_stun_init_success_response_str(STUN_METHOD_BINDING, buf, len, tid, cookie); } if (!old_stun && reflexive_addr) { if (!stun_attr_add_addr_str(buf, len, STUN_ATTRIBUTE_XOR_MAPPED_ADDRESS, reflexive_addr)) { return false; } } if (reflexive_addr) { if (stun_backward_compatibility && !stun_attr_add_addr_str(buf, len, STUN_ATTRIBUTE_MAPPED_ADDRESS, reflexive_addr)) { return false; } } } else if (!old_stun) { stun_init_error_response_str(STUN_METHOD_BINDING, buf, len, error_code, reason, tid); } else { old_stun_init_error_response_str(STUN_METHOD_BINDING, buf, len, error_code, reason, tid, cookie); } return true; } bool stun_is_binding_request_str(const uint8_t *buf, size_t len, size_t offset) { if (offset < len) { buf += offset; len -= offset; if (stun_is_command_message_str(buf, len)) { if (stun_is_request_str(buf, len) && (stun_get_method_str(buf, len) == STUN_METHOD_BINDING)) { return true; } } } return false; } bool stun_is_binding_response_str(const uint8_t *buf, size_t len) { if (stun_is_command_message_str(buf, len) && (stun_get_method_str(buf, len) == STUN_METHOD_BINDING)) { if (stun_is_response_str(buf, len)) { return true; } } return false; } /////////////////////////////// TID /////////////////////////////// bool stun_tid_equals(const stun_tid *id1, const stun_tid *id2) { if (!id1 || !id2) { return false; } if (id1 == id2) { return true; } for (size_t i = 0; i < STUN_TID_SIZE; ++i) { if (id1->tsx_id[i] != id2->tsx_id[i]) { return false; } } return true; } void stun_tid_cpy(stun_tid *id1, const stun_tid *id2) { if (!id1 || !id2) { return; } memcpy(id1->tsx_id, id2->tsx_id, STUN_TID_SIZE); } static void stun_tid_string_cpy(uint8_t *s, const stun_tid *id) { if (s && id) { memcpy(s, id->tsx_id, STUN_TID_SIZE); } } static void stun_tid_from_string(const uint8_t *s, stun_tid *id) { if (s && id) { memcpy(id->tsx_id, s, STUN_TID_SIZE); } } void stun_tid_from_message_str(const uint8_t *buf, size_t len, stun_tid *id) { UNUSED_ARG(len); stun_tid_from_string(buf + 8, id); } void stun_tid_message_cpy(uint8_t *buf, const stun_tid *id) { if (buf && id) { stun_tid_string_cpy(buf + 8, id); } } void stun_tid_generate(stun_tid *id) { if (id) { turn_random_tid_size(id->tsx_id); } } void stun_tid_generate_in_message_str(uint8_t *buf, stun_tid *id) { stun_tid tmp; if (!id) { id = &tmp; } stun_tid_generate(id); stun_tid_message_cpy(buf, id); } /////////////////// TIME //////////////////////////////////////////////////////// turn_time_t stun_adjust_allocate_lifetime(turn_time_t lifetime, turn_time_t max_allowed_lifetime, turn_time_t max_lifetime) { if (!lifetime) { lifetime = STUN_DEFAULT_ALLOCATE_LIFETIME; } else if (lifetime < STUN_MIN_ALLOCATE_LIFETIME) { lifetime = STUN_MIN_ALLOCATE_LIFETIME; } else if (lifetime > max_allowed_lifetime) { lifetime = max_allowed_lifetime; } if (max_lifetime && (max_lifetime < lifetime)) { lifetime = max_lifetime; } return lifetime; } ////////////// ATTR ///////////////////////////////////////////////////////////// int stun_attr_get_type(stun_attr_ref attr) { if (attr) { return (int)(nswap16(((const uint16_t *)attr)[0])); } return -1; } int stun_attr_get_len(stun_attr_ref attr) { if (attr) { return (int)(nswap16(((const uint16_t *)attr)[1])); } return -1; } const uint8_t *stun_attr_get_value(stun_attr_ref attr) { if (attr) { int len = (int)(nswap16(((const uint16_t *)attr)[1])); if (len < 1) { return NULL; } return ((const uint8_t *)attr) + 4; } return NULL; } int stun_get_requested_address_family(stun_attr_ref attr) { if (attr) { int len = (int)(nswap16(((const uint16_t *)attr)[1])); if (len != 4) { return STUN_ATTRIBUTE_REQUESTED_ADDRESS_FAMILY_VALUE_INVALID; } int val = ((const uint8_t *)attr)[4]; switch (val) { case STUN_ATTRIBUTE_REQUESTED_ADDRESS_FAMILY_VALUE_IPV4: case STUN_ATTRIBUTE_REQUESTED_ADDRESS_FAMILY_VALUE_IPV6: return val; default: return STUN_ATTRIBUTE_REQUESTED_ADDRESS_FAMILY_VALUE_INVALID; }; } return STUN_ATTRIBUTE_REQUESTED_ADDRESS_FAMILY_VALUE_DEFAULT; } uint16_t stun_attr_get_channel_number(stun_attr_ref attr) { if (attr) { const uint8_t *value = stun_attr_get_value(attr); if (value && (stun_attr_get_len(attr) >= 2)) { uint16_t cn = nswap16(((const uint16_t *)value)[0]); if (STUN_VALID_CHANNEL(cn)) { return cn; } } } return 0; } band_limit_t stun_attr_get_bandwidth(stun_attr_ref attr) { if (attr) { const uint8_t *value = stun_attr_get_value(attr); if (value && (stun_attr_get_len(attr) >= 4)) { uint32_t bps = nswap32(((const uint32_t *)value)[0]); return (band_limit_t)(bps << 7); } } return 0; } uint64_t stun_attr_get_reservation_token_value(stun_attr_ref attr) { if (attr) { const uint8_t *value = stun_attr_get_value(attr); if (value && (stun_attr_get_len(attr) == 8)) { uint64_t token; memcpy(&token, value, sizeof(uint64_t)); return nswap64(token); } } return 0; } bool stun_attr_is_addr(stun_attr_ref attr) { if (attr) { switch (stun_attr_get_type(attr)) { case STUN_ATTRIBUTE_XOR_MAPPED_ADDRESS: case STUN_ATTRIBUTE_XOR_PEER_ADDRESS: case STUN_ATTRIBUTE_XOR_RELAYED_ADDRESS: case STUN_ATTRIBUTE_MAPPED_ADDRESS: case STUN_ATTRIBUTE_ALTERNATE_SERVER: case OLD_STUN_ATTRIBUTE_RESPONSE_ADDRESS: case OLD_STUN_ATTRIBUTE_SOURCE_ADDRESS: case OLD_STUN_ATTRIBUTE_CHANGED_ADDRESS: case OLD_STUN_ATTRIBUTE_REFLECTED_FROM: case STUN_ATTRIBUTE_RESPONSE_ORIGIN: case STUN_ATTRIBUTE_OTHER_ADDRESS: return true; break; default:; }; } return false; } uint8_t stun_attr_get_even_port(stun_attr_ref attr) { if (attr) { const uint8_t *value = stun_attr_get_value(attr); if (value) { if ((uint8_t)(value[0]) > 0x7F) { return 1; } } } return 0; } stun_attr_ref stun_attr_get_first_by_type_str(const uint8_t *buf, size_t len, uint16_t attr_type) { stun_attr_ref attr = stun_attr_get_first_str(buf, len); while (attr) { if (stun_attr_get_type(attr) == attr_type) { return attr; } attr = stun_attr_get_next_str(buf, len, attr); } return NULL; } static stun_attr_ref stun_attr_check_valid(stun_attr_ref attr, size_t remaining) { if (remaining >= 4) { /* Read the size of the attribute */ size_t attrlen = stun_attr_get_len(attr); remaining -= 4; /* Round to boundary */ uint16_t rem4 = ((uint16_t)attrlen) & 0x0003; if (rem4) { attrlen = attrlen + 4 - (int)rem4; } /* Check that there's enough space remaining */ if (attrlen <= remaining) { return attr; } } return NULL; } stun_attr_ref stun_attr_get_first_str(const uint8_t *buf, size_t len) { int bufLen = stun_get_command_message_len_str(buf, len); if (bufLen > STUN_HEADER_LENGTH) { stun_attr_ref attr = (stun_attr_ref)(buf + STUN_HEADER_LENGTH); return stun_attr_check_valid(attr, bufLen - STUN_HEADER_LENGTH); } return NULL; } stun_attr_ref stun_attr_get_next_str(const uint8_t *buf, size_t len, stun_attr_ref prev) { if (!prev) { return stun_attr_get_first_str(buf, len); } else { const uint8_t *end = buf + stun_get_command_message_len_str(buf, len); int attrlen = stun_attr_get_len(prev); uint16_t rem4 = ((uint16_t)attrlen) & 0x0003; if (rem4) { attrlen = attrlen + 4 - (int)rem4; } /* Note the order here: operations on attrlen are untrusted as they may overflow */ if (attrlen < end - (const uint8_t *)prev - 4) { const uint8_t *attr_end = (const uint8_t *)prev + 4 + attrlen; return stun_attr_check_valid(attr_end, end - attr_end); } return NULL; } } bool stun_attr_add_str(uint8_t *buf, size_t *len, uint16_t attr, const uint8_t *avalue, int alen) { if (alen < 0) { alen = 0; } uint8_t tmp[1]; if (!avalue) { alen = 0; avalue = tmp; } int clen = stun_get_command_message_len_str(buf, *len); int newlen = clen + 4 + alen; int newlenrem4 = newlen & 0x00000003; int paddinglen = 0; if (newlenrem4) { paddinglen = 4 - newlenrem4; newlen = newlen + paddinglen; } if (newlen >= MAX_STUN_MESSAGE_SIZE) { return false; } uint8_t *attr_start = buf + clen; uint16_t *attr_start_16t = (uint16_t *)attr_start; stun_set_command_message_len_str(buf, newlen); *len = newlen; attr_start_16t[0] = nswap16(attr); attr_start_16t[1] = nswap16(alen); if (alen > 0) { memcpy(attr_start + 4, avalue, alen); } // Write 0 padding to not leak data memset(attr_start + 4 + alen, 0, paddinglen); return true; } bool stun_attr_add_addr_str(uint8_t *buf, size_t *len, uint16_t attr_type, const ioa_addr *ca) { stun_tid tid; stun_tid_from_message_str(buf, *len, &tid); int xor_ed = 0; switch (attr_type) { case STUN_ATTRIBUTE_XOR_MAPPED_ADDRESS: case STUN_ATTRIBUTE_XOR_PEER_ADDRESS: case STUN_ATTRIBUTE_XOR_RELAYED_ADDRESS: xor_ed = 1; break; default:; }; ioa_addr public_addr; map_addr_from_private_to_public(ca, &public_addr); uint8_t cfield[64]; int clen = 0; if (stun_addr_encode(&public_addr, cfield, &clen, xor_ed, STUN_MAGIC_COOKIE, tid.tsx_id) < 0) { return false; } if (!stun_attr_add_str(buf, len, attr_type, (uint8_t *)(&cfield), clen)) { return false; } return true; } bool stun_attr_get_addr_str(const uint8_t *buf, size_t len, stun_attr_ref attr, ioa_addr *ca, const ioa_addr *default_addr) { stun_tid tid; stun_tid_from_message_str(buf, len, &tid); ioa_addr public_addr; addr_set_any(ca); addr_set_any(&public_addr); int attr_type = stun_attr_get_type(attr); if (attr_type < 0) { return false; } int xor_ed = 0; switch (attr_type) { case STUN_ATTRIBUTE_XOR_MAPPED_ADDRESS: case STUN_ATTRIBUTE_XOR_PEER_ADDRESS: case STUN_ATTRIBUTE_XOR_RELAYED_ADDRESS: xor_ed = 1; break; default:; }; const uint8_t *cfield = stun_attr_get_value(attr); if (!cfield) { return false; } if (stun_addr_decode(&public_addr, cfield, stun_attr_get_len(attr), xor_ed, STUN_MAGIC_COOKIE, tid.tsx_id) < 0) { return false; } map_addr_from_public_to_private(&public_addr, ca); if (default_addr && addr_any_no_port(ca) && !addr_any_no_port(default_addr)) { int port = addr_get_port(ca); addr_cpy(ca, default_addr); addr_set_port(ca, port); } return true; } bool stun_attr_get_first_addr_str(const uint8_t *buf, size_t len, uint16_t attr_type, ioa_addr *ca, const ioa_addr *default_addr) { stun_attr_ref attr = stun_attr_get_first_str(buf, len); while (attr) { if (stun_attr_is_addr(attr) && (attr_type == stun_attr_get_type(attr))) { if (stun_attr_get_addr_str(buf, len, attr, ca, default_addr)) { return true; } } attr = stun_attr_get_next_str(buf, len, attr); } return false; } bool stun_attr_add_channel_number_str(uint8_t *buf, size_t *len, uint16_t chnumber) { uint16_t field[2]; field[0] = nswap16(chnumber); field[1] = 0; return stun_attr_add_str(buf, len, STUN_ATTRIBUTE_CHANNEL_NUMBER, (uint8_t *)(field), sizeof(field)); } bool stun_attr_add_bandwidth_str(uint8_t *buf, size_t *len, band_limit_t bps0) { uint32_t bps = (uint32_t)(band_limit_t)(bps0 >> 7); uint32_t field = nswap32(bps); return stun_attr_add_str(buf, len, STUN_ATTRIBUTE_NEW_BANDWIDTH, (uint8_t *)(&field), sizeof(field)); } bool stun_attr_add_address_error_code(uint8_t *buf, size_t *len, int requested_address_family, int error_code) { const uint8_t *reason = get_default_reason(error_code); uint8_t avalue[513]; avalue[0] = (uint8_t)requested_address_family; avalue[1] = 0; avalue[2] = (uint8_t)(error_code / 100); avalue[3] = (uint8_t)(error_code % 100); strncpy((char *)(avalue + 4), (const char *)reason, sizeof(avalue) - 4); avalue[sizeof(avalue) - 1] = 0; int alen = 4 + (int)strlen((const char *)(avalue + 4)); //"Manual" padding for compatibility with classic old stun: { int rem = alen % 4; if (rem) { alen += (4 - rem); } } return stun_attr_add_str(buf, len, STUN_ATTRIBUTE_ADDRESS_ERROR_CODE, (uint8_t *)avalue, alen); } uint16_t stun_attr_get_first_channel_number_str(const uint8_t *buf, size_t len) { stun_attr_ref attr = stun_attr_get_first_str(buf, len); while (attr) { if (stun_attr_get_type(attr) == STUN_ATTRIBUTE_CHANNEL_NUMBER) { uint16_t ret = stun_attr_get_channel_number(attr); if (STUN_VALID_CHANNEL(ret)) { return ret; } } attr = stun_attr_get_next_str(buf, len, attr); } return 0; } ////////////// FINGERPRINT //////////////////////////// bool stun_attr_add_fingerprint_str(uint8_t *buf, size_t *len) { uint32_t crc32 = 0; if (!stun_attr_add_str(buf, len, STUN_ATTRIBUTE_FINGERPRINT, (uint8_t *)&crc32, 4)) { return false; } crc32 = ns_crc32(buf, (int)*len - 8); *((uint32_t *)(buf + *len - 4)) = nswap32(crc32 ^ ((uint32_t)FINGERPRINT_XOR)); return true; } ////////////// CRC /////////////////////////////////////////////// #define CRC_MASK 0xFFFFFFFFUL #define UPDATE_CRC(crc, c) crc = crctable[(uint8_t)crc ^ (uint8_t)(c)] ^ (crc >> 8) static const uint32_t crctable[256] = { 0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f, 0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988, 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7, 0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9, 0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172, 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, 0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59, 0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423, 0xcfba9599, 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924, 0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, 0x01db7106, 0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433, 0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e, 0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950, 0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65, 0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0, 0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa, 0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f, 0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a, 0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1, 0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb, 0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc, 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b, 0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55, 0x316e8eef, 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236, 0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d, 0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38, 0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242, 0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777, 0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2, 0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc, 0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9, 0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693, 0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94, 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d, }; static uint32_t ns_crc32(const uint8_t *buffer, uint32_t len) { uint32_t crc = CRC_MASK; while (len--) { UPDATE_CRC(crc, *buffer++); } return (~crc); } //////////// SASLprep RFC 4013 ///////////////////////////////////////// /* We support only basic ASCII table */ bool SASLprep(uint8_t *s) { if (s) { uint8_t *strin = s; uint8_t *strout = s; for (;;) { uint8_t c = *strin; if (!c) { *strout = 0; break; } switch (c) { case 0xAD: ++strin; break; case 0xA0: case 0x20: *strout = 0x20; ++strout; ++strin; break; case 0x7F: return false; default: if (c < 0x1F) { return false; } if (c >= 0x80 && c <= 0x9F) { return false; } *strout = c; ++strout; ++strin; }; } } return true; } //////////////// Message Integrity //////////////////////////// size_t get_hmackey_size(SHATYPE shatype) { if (shatype == SHATYPE_SHA256) { return 32; } if (shatype == SHATYPE_SHA384) { return 48; } if (shatype == SHATYPE_SHA512) { return 64; } return 16; } void print_bin_func(const char *name, size_t len, const void *s, const char *func) { printf("<%s>:<%s>:len=%d:[", func, name, (int)len); for (size_t i = 0; i < len; i++) { printf("%02x", (int)((const uint8_t *)s)[i]); } printf("]\n"); } bool stun_attr_add_integrity_str(turn_credential_type ct, uint8_t *buf, size_t *len, hmackey_t key, password_t pwd, SHATYPE shatype) { uint8_t hmac[MAXSHASIZE]; unsigned int shasize; switch (shatype) { case SHATYPE_SHA256: shasize = SHA256SIZEBYTES; break; case SHATYPE_SHA384: shasize = SHA384SIZEBYTES; break; case SHATYPE_SHA512: shasize = SHA512SIZEBYTES; break; default: shasize = SHA1SIZEBYTES; }; if (!stun_attr_add_str(buf, len, STUN_ATTRIBUTE_MESSAGE_INTEGRITY, hmac, shasize)) { return false; } if (ct == TURN_CREDENTIALS_SHORT_TERM) { return stun_calculate_hmac(buf, *len - 4 - shasize, pwd, strlen((char *)pwd), buf + *len - shasize, &shasize, shatype); } else { return stun_calculate_hmac(buf, *len - 4 - shasize, key, get_hmackey_size(shatype), buf + *len - shasize, &shasize, shatype); } } bool stun_attr_add_integrity_by_key_str(uint8_t *buf, size_t *len, const uint8_t *uname, const uint8_t *realm, hmackey_t key, const uint8_t *nonce, SHATYPE shatype) { if (!stun_attr_add_str(buf, len, STUN_ATTRIBUTE_USERNAME, uname, (int)strlen((const char *)uname))) { return false; } if (!stun_attr_add_str(buf, len, STUN_ATTRIBUTE_NONCE, nonce, (int)strlen((const char *)nonce))) { return false; } if (!stun_attr_add_str(buf, len, STUN_ATTRIBUTE_REALM, realm, (int)strlen((const char *)realm))) { return false; } password_t p; return stun_attr_add_integrity_str(TURN_CREDENTIALS_LONG_TERM, buf, len, key, p, shatype); } bool stun_attr_add_integrity_by_user_str(uint8_t *buf, size_t *len, const uint8_t *uname, const uint8_t *realm, const uint8_t *upwd, const uint8_t *nonce, SHATYPE shatype) { hmackey_t key; if (!stun_produce_integrity_key_str(uname, realm, upwd, key, shatype)) { return false; } return stun_attr_add_integrity_by_key_str(buf, len, uname, realm, key, nonce, shatype); } bool stun_attr_add_integrity_by_user_short_term_str(uint8_t *buf, size_t *len, const uint8_t *uname, password_t pwd, SHATYPE shatype) { if (stun_attr_add_str(buf, len, STUN_ATTRIBUTE_USERNAME, uname, (int)strlen((const char *)uname))) { return false; } hmackey_t key; return stun_attr_add_integrity_str(TURN_CREDENTIALS_SHORT_TERM, buf, len, key, pwd, shatype); } /* * Return -1 if failure, 0 if the integrity is not correct, 1 if OK */ int stun_check_message_integrity_by_key_str(turn_credential_type ct, uint8_t *buf, size_t len, hmackey_t key, password_t pwd, SHATYPE shatype) { stun_attr_ref sar = stun_attr_get_first_by_type_str(buf, len, STUN_ATTRIBUTE_MESSAGE_INTEGRITY); if (!sar) { return -1; } unsigned int shasize = 0; switch (stun_attr_get_len(sar)) { case SHA256SIZEBYTES: shasize = SHA256SIZEBYTES; if (shatype != SHATYPE_SHA256) { return -1; } break; case SHA384SIZEBYTES: shasize = SHA384SIZEBYTES; if (shatype != SHATYPE_SHA384) { return -1; } break; case SHA512SIZEBYTES: shasize = SHA512SIZEBYTES; if (shatype != SHATYPE_SHA512) { return -1; } break; case SHA1SIZEBYTES: shasize = SHA1SIZEBYTES; if (shatype != SHATYPE_SHA1) { return -1; } break; default: return -1; }; int orig_len = stun_get_command_message_len_str(buf, len); if (orig_len < 0) { return -1; } int new_len = (int)((const uint8_t *)sar - buf) + 4 + shasize; if (new_len > orig_len) { return -1; } if (!stun_set_command_message_len_str(buf, new_len)) { return -1; } int res = 0; uint8_t new_hmac[MAXSHASIZE] = {0}; if (ct == TURN_CREDENTIALS_SHORT_TERM) { if (!stun_calculate_hmac(buf, (size_t)new_len - 4 - shasize, pwd, strlen((char *)pwd), new_hmac, &shasize, shatype)) { res = -1; } else { res = 0; } } else { if (!stun_calculate_hmac(buf, (size_t)new_len - 4 - shasize, key, get_hmackey_size(shatype), new_hmac, &shasize, shatype)) { res = -1; } else { res = 0; } } stun_set_command_message_len_str(buf, orig_len); if (res < 0) { return -1; } const uint8_t *old_hmac = stun_attr_get_value(sar); if (!old_hmac) { return -1; } if (0 != memcmp(old_hmac, new_hmac, shasize)) { return 0; } return +1; } /* * Return -1 if failure, 0 if the integrity is not correct, 1 if OK */ int stun_check_message_integrity_str(turn_credential_type ct, uint8_t *buf, size_t len, const uint8_t *uname, const uint8_t *realm, const uint8_t *upwd, SHATYPE shatype) { hmackey_t key; password_t pwd; if (ct == TURN_CREDENTIALS_SHORT_TERM) { strncpy((char *)pwd, (const char *)upwd, sizeof(password_t) - 1); pwd[sizeof(password_t) - 1] = 0; } else if (!stun_produce_integrity_key_str(uname, realm, upwd, key, shatype)) { return -1; } return stun_check_message_integrity_by_key_str(ct, buf, len, key, pwd, shatype); } /* RFC 5780 */ bool stun_attr_get_change_request_str(stun_attr_ref attr, bool *change_ip, bool *change_port) { if (stun_attr_get_len(attr) == 4) { const uint8_t *value = stun_attr_get_value(attr); if (value) { *change_ip = (value[3] & 0x04); *change_port = (value[3] & 0x02); return true; } } return false; } bool stun_attr_add_change_request_str(uint8_t *buf, size_t *len, bool change_ip, bool change_port) { uint8_t avalue[4] = {0, 0, 0, 0}; if (change_ip) { if (change_port) { avalue[3] = 0x06; } else { avalue[3] = 0x04; } } else if (change_port) { avalue[3] = 0x02; } return stun_attr_add_str(buf, len, STUN_ATTRIBUTE_CHANGE_REQUEST, avalue, 4); } int stun_attr_get_response_port_str(stun_attr_ref attr) { if (stun_attr_get_len(attr) >= 2) { const uint8_t *value = stun_attr_get_value(attr); if (value) { return nswap16(((const uint16_t *)value)[0]); } } return -1; } bool stun_attr_add_response_port_str(uint8_t *buf, size_t *len, uint16_t port) { uint8_t avalue[4] = {0, 0, 0, 0}; uint16_t *port_ptr = (uint16_t *)avalue; *port_ptr = nswap16(port); return stun_attr_add_str(buf, len, STUN_ATTRIBUTE_RESPONSE_PORT, avalue, 4); } int stun_attr_get_padding_len_str(stun_attr_ref attr) { int len = stun_attr_get_len(attr); if (len < 0) { return -1; } return (uint16_t)len; } bool stun_attr_add_padding_str(uint8_t *buf, size_t *len, uint16_t padding_len) { uint8_t avalue[0xFFFF]; memset(avalue, 0, padding_len); return stun_attr_add_str(buf, len, STUN_ATTRIBUTE_PADDING, avalue, padding_len); } /* OAUTH */ #define OAUTH_ERROR(...) fprintf(stderr, __VA_ARGS__) static void remove_spaces(char *s) { char *sfns = s; while (*sfns) { if (*sfns != ' ') { break; } ++sfns; } if (*sfns) { if (sfns != s) { while (*sfns && (*sfns != ' ')) { *s = *sfns; ++s; ++sfns; }; *s = 0; } else { while (*s) { if (*s == ' ') { *s = 0; break; } ++s; } } } } static void normalize_algorithm(char *s) { char c = *s; while (c) { if (c == '_') { *s = '-'; } else if ((c >= 'a') && (c <= 'z')) { *s = c - 'a' + 'A'; } ++s; c = *s; } } size_t calculate_enc_key_length(ENC_ALG a); size_t calculate_enc_key_length(ENC_ALG a) { switch (a) { #if !defined(TURN_NO_GCM) case A128GCM: return 16; #endif default: break; }; return 32; } size_t calculate_auth_key_length(ENC_ALG a); size_t calculate_auth_key_length(ENC_ALG a) { switch (a) { #if !defined(TURN_NO_GCM) case A256GCM: case A128GCM: return 0; #endif default: break; }; return 0; } static bool calculate_key(char *key, size_t key_size, char *new_key, size_t new_key_size); static bool calculate_key(char *key, size_t key_size, char *new_key, size_t new_key_size) { UNUSED_ARG(key_size); memcpy(new_key, key, new_key_size); return true; } bool convert_oauth_key_data(const oauth_key_data *oakd0, oauth_key *key, char *err_msg, size_t err_msg_size) { #if !defined(TURN_NO_OAUTH) if (oakd0 && key) { oauth_key_data oakd_obj; memcpy(&oakd_obj, oakd0, sizeof(oauth_key_data)); oauth_key_data *oakd = &oakd_obj; if (!(oakd->ikm_key_size)) { if (err_msg) { snprintf(err_msg, err_msg_size, "key is not defined"); } } remove_spaces(oakd->kid); remove_spaces(oakd->as_rs_alg); normalize_algorithm(oakd->as_rs_alg); if (!(oakd->kid[0])) { if (err_msg) { snprintf(err_msg, err_msg_size, "KID is not defined"); } OAUTH_ERROR("KID is not defined\n"); return false; } memset(key, 0, sizeof(oauth_key)); STRCPY(key->kid, oakd->kid); memcpy(key->ikm_key, oakd->ikm_key, sizeof(key->ikm_key)); key->ikm_key_size = oakd->ikm_key_size; key->timestamp = oakd->timestamp; key->lifetime = oakd->lifetime; if (!(key->timestamp)) { key->timestamp = OAUTH_DEFAULT_TIMESTAMP; } if (!(key->lifetime)) { key->lifetime = OAUTH_DEFAULT_LIFETIME; } key->as_rs_alg = ENC_ALG_ERROR; #if !defined(TURN_NO_GCM) key->as_rs_alg = ENC_ALG_DEFAULT; if (!strcmp(oakd->as_rs_alg, "A128GCM")) { key->as_rs_alg = A128GCM; key->auth_key_size = 0; key->auth_key[0] = 0; } else if (!strcmp(oakd->as_rs_alg, "A256GCM")) { key->as_rs_alg = A256GCM; key->auth_key_size = 0; key->auth_key[0] = 0; } else #endif { if (err_msg) { snprintf(err_msg, err_msg_size, "Wrong oAuth token encryption algorithm: %s (2)\n", oakd->as_rs_alg); } OAUTH_ERROR("Wrong oAuth token encryption algorithm: %s (3)\n", oakd->as_rs_alg); return false; } #if !defined(TURN_NO_GCM) key->auth_key_size = calculate_auth_key_length(key->as_rs_alg); if (key->auth_key_size) { if (!calculate_key(key->ikm_key, key->ikm_key_size, key->auth_key, key->auth_key_size)) { return false; } } key->as_rs_key_size = calculate_enc_key_length(key->as_rs_alg); if (!calculate_key(key->ikm_key, key->ikm_key_size, key->as_rs_key, key->as_rs_key_size)) { return false; } #endif } return true; #else OAUTH_ERROR("Oauth support not included"); return false; #endif } #if !defined(TURN_NO_OAUTH) const EVP_CIPHER *get_cipher_type(ENC_ALG enc_alg); const EVP_CIPHER *get_cipher_type(ENC_ALG enc_alg) { switch (enc_alg) { #if !defined(TURN_NO_GCM) case A128GCM: return EVP_aes_128_gcm(); case A256GCM: return EVP_aes_256_gcm(); #endif default: break; } OAUTH_ERROR("%s: Unsupported enc algorithm: %d\n", __FUNCTION__, (int)enc_alg); return NULL; } int my_EVP_EncryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl, const unsigned char *in, int inl); int my_EVP_EncryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl, const unsigned char *in, int inl) { int cycle = 0; int out_len = 0; while ((out_len < inl) && (++cycle < 128)) { int tmp_outl = 0; unsigned char *ptr = NULL; if (out) { ptr = out + out_len; } int ret = EVP_EncryptUpdate(ctx, ptr, &tmp_outl, in + out_len, inl - out_len); out_len += tmp_outl; if (ret < 1) { return ret; } } *outl = out_len; return 1; } int my_EVP_DecryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl, const unsigned char *in, int inl); int my_EVP_DecryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl, const unsigned char *in, int inl) { int cycle = 0; int out_len = 0; while ((out_len < inl) && (++cycle < 128)) { int tmp_outl = 0; unsigned char *ptr = NULL; if (out) { ptr = out + out_len; } int ret = EVP_DecryptUpdate(ctx, ptr, &tmp_outl, in + out_len, inl - out_len); out_len += tmp_outl; if (ret < 1) { return ret; } } *outl = out_len; return 1; } #if !defined(TURN_NO_GCM) static bool encode_oauth_token_gcm(const uint8_t *server_name, encoded_oauth_token *etoken, const oauth_key *key, const oauth_token *dtoken, const uint8_t *nonce0) { if (server_name && etoken && key && dtoken && (dtoken->enc_block.key_length <= MAXSHASIZE)) { unsigned char orig_field[MAX_ENCODED_OAUTH_TOKEN_SIZE]; memset(orig_field, 0, sizeof(orig_field)); unsigned char nonce[OAUTH_GCM_NONCE_SIZE]; if (nonce0) { memcpy(nonce, nonce0, sizeof(nonce)); } else { generate_random_nonce(nonce, sizeof(nonce)); } size_t len = 0; *((uint16_t *)(orig_field + len)) = nswap16(OAUTH_GCM_NONCE_SIZE); len += 2; memcpy(orig_field + len, nonce, OAUTH_GCM_NONCE_SIZE); len += OAUTH_GCM_NONCE_SIZE; *((uint16_t *)(orig_field + len)) = nswap16(dtoken->enc_block.key_length); len += 2; memcpy(orig_field + len, dtoken->enc_block.mac_key, dtoken->enc_block.key_length); len += dtoken->enc_block.key_length; uint64_t ts = nswap64(dtoken->enc_block.timestamp); memcpy((orig_field + len), &ts, sizeof(ts)); len += sizeof(ts); *((uint32_t *)(orig_field + len)) = nswap32(dtoken->enc_block.lifetime); len += 4; const EVP_CIPHER *cipher = get_cipher_type(key->as_rs_alg); if (!cipher) { return false; } EVP_CIPHER_CTX *ctxp = EVP_CIPHER_CTX_new(); EVP_CIPHER_CTX_init(ctxp); /* Initialize the encryption operation. */ if (1 != EVP_EncryptInit_ex(ctxp, cipher, NULL, NULL, NULL)) { return -1; } EVP_CIPHER_CTX_set_padding(ctxp, 1); /* Set IV length if default 12 bytes (96 bits) is not appropriate */ if (1 != EVP_CIPHER_CTX_ctrl(ctxp, EVP_CTRL_GCM_SET_IVLEN, OAUTH_GCM_NONCE_SIZE, NULL)) { return false; } /* Initialize key and IV */ if (1 != EVP_EncryptInit_ex(ctxp, NULL, NULL, (const unsigned char *)key->as_rs_key, nonce)) { return false; } int outl = 0; size_t sn_len = strlen((const char *)server_name); /* Provide any AAD data. This can be called zero or more times as * required */ if (1 != my_EVP_EncryptUpdate(ctxp, NULL, &outl, server_name, (int)sn_len)) { return false; } outl = 0; unsigned char *encoded_field = (unsigned char *)etoken->token; memcpy(encoded_field, orig_field, OAUTH_GCM_NONCE_SIZE + 2); encoded_field += OAUTH_GCM_NONCE_SIZE + 2; unsigned char *start_field = orig_field + OAUTH_GCM_NONCE_SIZE + 2; len -= OAUTH_GCM_NONCE_SIZE + 2; if (1 != my_EVP_EncryptUpdate(ctxp, encoded_field, &outl, start_field, (int)len)) { return -1; } int tmp_outl = 0; EVP_EncryptFinal_ex(ctxp, encoded_field + outl, &tmp_outl); outl += tmp_outl; EVP_CIPHER_CTX_ctrl(ctxp, EVP_CTRL_GCM_GET_TAG, OAUTH_GCM_TAG_SIZE, encoded_field + outl); outl += OAUTH_GCM_TAG_SIZE; etoken->size = 2 + OAUTH_GCM_NONCE_SIZE + outl; EVP_CIPHER_CTX_free(ctxp); return true; } return false; } static bool decode_oauth_token_gcm(const uint8_t *server_name, const encoded_oauth_token *etoken, const oauth_key *key, oauth_token *dtoken) { if (server_name && etoken && key && dtoken) { unsigned char snl[2]; memcpy(snl, (const unsigned char *)(etoken->token), 2); const unsigned char *csnl = snl; uint16_t nonce_len = nswap16(*((const uint16_t *)csnl)); dtoken->enc_block.nonce_length = nonce_len; size_t min_encoded_field_size = 2 + 4 + 8 + nonce_len + 2 + OAUTH_GCM_TAG_SIZE + 1; if (etoken->size < min_encoded_field_size) { OAUTH_ERROR("%s: token size too small: %d\n", __FUNCTION__, (int)etoken->size); return false; } const unsigned char *encoded_field = (const unsigned char *)(etoken->token + nonce_len + 2); unsigned int encoded_field_size = (unsigned int)etoken->size - nonce_len - 2 - OAUTH_GCM_TAG_SIZE; const unsigned char *nonce = ((const unsigned char *)etoken->token + 2); memcpy(dtoken->enc_block.nonce, nonce, nonce_len); unsigned char tag[OAUTH_GCM_TAG_SIZE]; memcpy(tag, ((const unsigned char *)etoken->token) + nonce_len + 2 + encoded_field_size, sizeof(tag)); unsigned char decoded_field[MAX_ENCODED_OAUTH_TOKEN_SIZE]; const EVP_CIPHER *cipher = get_cipher_type(key->as_rs_alg); if (!cipher) { OAUTH_ERROR("%s: Cannot find cipher for algorithm: %d\n", __FUNCTION__, (int)key->as_rs_alg); return false; } EVP_CIPHER_CTX *ctxp = EVP_CIPHER_CTX_new(); EVP_CIPHER_CTX_init(ctxp); /* Initialize the decryption operation. */ if (1 != EVP_DecryptInit_ex(ctxp, cipher, NULL, NULL, NULL)) { OAUTH_ERROR("%s: Cannot initialize decryption\n", __FUNCTION__); return false; } // EVP_CIPHER_CTX_set_padding(&ctx,1); /* Set IV length if default 12 bytes (96 bits) is not appropriate */ if (1 != EVP_CIPHER_CTX_ctrl(ctxp, EVP_CTRL_GCM_SET_IVLEN, nonce_len, NULL)) { OAUTH_ERROR("%s: Cannot set nonce length\n", __FUNCTION__); return false; } /* Initialize key and IV */ if (1 != EVP_DecryptInit_ex(ctxp, NULL, NULL, (const unsigned char *)key->as_rs_key, nonce)) { OAUTH_ERROR("%s: Cannot set nonce\n", __FUNCTION__); return false; } /* Set expected tag value. A restriction in OpenSSL 1.0.1c and earlier + * required the tag before any AAD or ciphertext */ EVP_CIPHER_CTX_ctrl(ctxp, EVP_CTRL_GCM_SET_TAG, OAUTH_GCM_TAG_SIZE, tag); int outl = 0; size_t sn_len = strlen((const char *)server_name); /* Provide any AAD data. This can be called zero or more times as * required */ if (1 != my_EVP_DecryptUpdate(ctxp, NULL, &outl, server_name, (int)sn_len)) { OAUTH_ERROR("%s: Cannot decrypt update server_name: %s, len=%d\n", __FUNCTION__, server_name, (int)sn_len); return false; } if (1 != my_EVP_DecryptUpdate(ctxp, decoded_field, &outl, encoded_field, (int)encoded_field_size)) { OAUTH_ERROR("%s: Cannot decrypt update\n", __FUNCTION__); return false; } int tmp_outl = 0; if (EVP_DecryptFinal_ex(ctxp, decoded_field + outl, &tmp_outl) < 1) { EVP_CIPHER_CTX_free(ctxp); OAUTH_ERROR("%s: token integrity check failed\n", __FUNCTION__); return false; } outl += tmp_outl; EVP_CIPHER_CTX_free(ctxp); size_t len = 0; dtoken->enc_block.key_length = nswap16(*((uint16_t *)(decoded_field + len))); len += 2; memcpy(dtoken->enc_block.mac_key, decoded_field + len, dtoken->enc_block.key_length); len += dtoken->enc_block.key_length; uint64_t ts; memcpy(&ts, (decoded_field + len), sizeof(ts)); dtoken->enc_block.timestamp = nswap64(ts); len += sizeof(ts); uint32_t lt; memcpy(<, (decoded_field + len), sizeof(lt)); dtoken->enc_block.lifetime = nswap32(lt); len += sizeof(lt); return true; } return false; } #endif #endif bool encode_oauth_token(const uint8_t *server_name, encoded_oauth_token *etoken, const oauth_key *key, const oauth_token *dtoken, const uint8_t *nonce) { #if !defined(TURN_NO_OAUTH) UNUSED_ARG(nonce); if (server_name && etoken && key && dtoken) { switch (key->as_rs_alg) { #if !defined(TURN_NO_GCM) case A256GCM: case A128GCM: return encode_oauth_token_gcm(server_name, etoken, key, dtoken, nonce); #endif default: fprintf(stderr, "Unsupported AS_RS algorithm: %d\n", (int)key->as_rs_alg); break; }; } return false; #else OAUTH_ERROR("Oauth support not included"); return false; #endif } bool decode_oauth_token(const uint8_t *server_name, const encoded_oauth_token *etoken, const oauth_key *key, oauth_token *dtoken) { #if !defined(TURN_NO_OAUTH) if (server_name && etoken && key && dtoken) { switch (key->as_rs_alg) { #if !defined(TURN_NO_GCM) case A256GCM: case A128GCM: return decode_oauth_token_gcm(server_name, etoken, key, dtoken); #endif default: fprintf(stderr, "Unsupported AS_RS algorithm: %d\n", (int)key->as_rs_alg); break; }; } return false; #else OAUTH_ERROR("Oauth support not included"); return false; #endif } ///////////////////////////////////////////////////////////////