/* * TLS v1.0/v1.1/v1.2 client (RFC 2246, RFC 4346, RFC 5246) * Copyright (c) 2006-2011, Jouni Malinen <j@w1.fi> * * This software may be distributed under the terms of the BSD license. * See README for more details. */ #include "includes.h" #include "common.h" #include "crypto/sha1.h" #include "crypto/tls.h" #include "tlsv1_common.h" #include "tlsv1_record.h" #include "tlsv1_client.h" #include "tlsv1_client_i.h" /* TODO: * Support for a message fragmented across several records (RFC 2246, 6.2.1) */ void tls_alert(struct tlsv1_client *conn, u8 level, u8 description) { conn->alert_level = level; conn->alert_description = description; } void tlsv1_client_free_dh(struct tlsv1_client *conn) { os_free(conn->dh_p); os_free(conn->dh_g); os_free(conn->dh_ys); conn->dh_p = conn->dh_g = conn->dh_ys = NULL; } int tls_derive_pre_master_secret(u8 *pre_master_secret) { WPA_PUT_BE16(pre_master_secret, TLS_VERSION); if (os_get_random(pre_master_secret + 2, TLS_PRE_MASTER_SECRET_LEN - 2)) return -1; return 0; } int tls_derive_keys(struct tlsv1_client *conn, const u8 *pre_master_secret, size_t pre_master_secret_len) { u8 seed[2 * TLS_RANDOM_LEN]; u8 key_block[TLS_MAX_KEY_BLOCK_LEN]; u8 *pos; size_t key_block_len; if (pre_master_secret) { wpa_hexdump_key(MSG_MSGDUMP, "TLSv1: pre_master_secret", pre_master_secret, pre_master_secret_len); os_memcpy(seed, conn->client_random, TLS_RANDOM_LEN); os_memcpy(seed + TLS_RANDOM_LEN, conn->server_random, TLS_RANDOM_LEN); if (tls_prf(conn->rl.tls_version, pre_master_secret, pre_master_secret_len, "master secret", seed, 2 * TLS_RANDOM_LEN, conn->master_secret, TLS_MASTER_SECRET_LEN)) { wpa_printf(MSG_DEBUG, "TLSv1: Failed to derive " "master_secret"); return -1; } wpa_hexdump_key(MSG_MSGDUMP, "TLSv1: master_secret", conn->master_secret, TLS_MASTER_SECRET_LEN); } os_memcpy(seed, conn->server_random, TLS_RANDOM_LEN); os_memcpy(seed + TLS_RANDOM_LEN, conn->client_random, TLS_RANDOM_LEN); key_block_len = 2 * (conn->rl.hash_size + conn->rl.key_material_len); if (conn->rl.tls_version == TLS_VERSION_1) key_block_len += 2 * conn->rl.iv_size; if (tls_prf(conn->rl.tls_version, conn->master_secret, TLS_MASTER_SECRET_LEN, "key expansion", seed, 2 * TLS_RANDOM_LEN, key_block, key_block_len)) { wpa_printf(MSG_DEBUG, "TLSv1: Failed to derive key_block"); return -1; } wpa_hexdump_key(MSG_MSGDUMP, "TLSv1: key_block", key_block, key_block_len); pos = key_block; /* client_write_MAC_secret */ os_memcpy(conn->rl.write_mac_secret, pos, conn->rl.hash_size); pos += conn->rl.hash_size; /* server_write_MAC_secret */ os_memcpy(conn->rl.read_mac_secret, pos, conn->rl.hash_size); pos += conn->rl.hash_size; /* client_write_key */ os_memcpy(conn->rl.write_key, pos, conn->rl.key_material_len); pos += conn->rl.key_material_len; /* server_write_key */ os_memcpy(conn->rl.read_key, pos, conn->rl.key_material_len); pos += conn->rl.key_material_len; if (conn->rl.tls_version == TLS_VERSION_1) { /* client_write_IV */ os_memcpy(conn->rl.write_iv, pos, conn->rl.iv_size); pos += conn->rl.iv_size; /* server_write_IV */ os_memcpy(conn->rl.read_iv, pos, conn->rl.iv_size); pos += conn->rl.iv_size; } else { /* * Use IV field to set the mask value for TLS v1.1. A fixed * mask of zero is used per the RFC 4346, 6.2.3.2 CBC Block * Cipher option 2a. */ os_memset(conn->rl.write_iv, 0, conn->rl.iv_size); } return 0; } /** * tlsv1_client_handshake - Process TLS handshake * @conn: TLSv1 client connection data from tlsv1_client_init() * @in_data: Input data from TLS peer * @in_len: Input data length * @out_len: Length of the output buffer. * @appl_data: Pointer to application data pointer, or %NULL if dropped * @appl_data_len: Pointer to variable that is set to appl_data length * @need_more_data: Set to 1 if more data would be needed to complete * processing * Returns: Pointer to output data, %NULL on failure */ u8 * tlsv1_client_handshake(struct tlsv1_client *conn, const u8 *in_data, size_t in_len, size_t *out_len, u8 **appl_data, size_t *appl_data_len, int *need_more_data) { const u8 *pos, *end; u8 *msg = NULL, *in_msg = NULL, *in_pos, *in_end, alert, ct; size_t in_msg_len; int no_appl_data; int used; if (need_more_data) *need_more_data = 0; if (conn->state == CLIENT_HELLO) { if (in_len) return NULL; return tls_send_client_hello(conn, out_len); } if (conn->partial_input) { if (wpabuf_resize(&conn->partial_input, in_len) < 0) { wpa_printf(MSG_DEBUG, "TLSv1: Failed to allocate " "memory for pending record"); tls_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_INTERNAL_ERROR); goto failed; } wpabuf_put_data(conn->partial_input, in_data, in_len); in_data = wpabuf_head(conn->partial_input); in_len = wpabuf_len(conn->partial_input); } if (in_data == NULL || in_len == 0) return NULL; pos = in_data; end = in_data + in_len; in_msg = os_malloc(in_len); if (in_msg == NULL) return NULL; /* Each received packet may include multiple records */ while (pos < end) { in_msg_len = in_len; used = tlsv1_record_receive(&conn->rl, pos, end - pos, in_msg, &in_msg_len, &alert); if (used < 0) { wpa_printf(MSG_DEBUG, "TLSv1: Processing received " "record failed"); tls_alert(conn, TLS_ALERT_LEVEL_FATAL, alert); goto failed; } if (used == 0) { struct wpabuf *partial; wpa_printf(MSG_DEBUG, "TLSv1: Need more data"); partial = wpabuf_alloc_copy(pos, end - pos); wpabuf_free(conn->partial_input); conn->partial_input = partial; if (conn->partial_input == NULL) { wpa_printf(MSG_DEBUG, "TLSv1: Failed to " "allocate memory for pending " "record"); tls_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_INTERNAL_ERROR); goto failed; } os_free(in_msg); if (need_more_data) *need_more_data = 1; return NULL; } ct = pos[0]; in_pos = in_msg; in_end = in_msg + in_msg_len; /* Each received record may include multiple messages of the * same ContentType. */ while (in_pos < in_end) { in_msg_len = in_end - in_pos; if (tlsv1_client_process_handshake(conn, ct, in_pos, &in_msg_len, appl_data, appl_data_len) < 0) goto failed; in_pos += in_msg_len; } pos += used; } os_free(in_msg); in_msg = NULL; no_appl_data = appl_data == NULL || *appl_data == NULL; msg = tlsv1_client_handshake_write(conn, out_len, no_appl_data); failed: os_free(in_msg); if (conn->alert_level) { wpabuf_free(conn->partial_input); conn->partial_input = NULL; conn->state = FAILED; os_free(msg); msg = tlsv1_client_send_alert(conn, conn->alert_level, conn->alert_description, out_len); } else if (msg == NULL) { msg = os_zalloc(1); *out_len = 0; } if (need_more_data == NULL || !(*need_more_data)) { wpabuf_free(conn->partial_input); conn->partial_input = NULL; } return msg; } /** * tlsv1_client_encrypt - Encrypt data into TLS tunnel * @conn: TLSv1 client connection data from tlsv1_client_init() * @in_data: Pointer to plaintext data to be encrypted * @in_len: Input buffer length * @out_data: Pointer to output buffer (encrypted TLS data) * @out_len: Maximum out_data length * Returns: Number of bytes written to out_data, -1 on failure * * This function is used after TLS handshake has been completed successfully to * send data in the encrypted tunnel. */ int tlsv1_client_encrypt(struct tlsv1_client *conn, const u8 *in_data, size_t in_len, u8 *out_data, size_t out_len) { size_t rlen; wpa_hexdump_key(MSG_MSGDUMP, "TLSv1: Plaintext AppData", in_data, in_len); if (tlsv1_record_send(&conn->rl, TLS_CONTENT_TYPE_APPLICATION_DATA, out_data, out_len, in_data, in_len, &rlen) < 0) { wpa_printf(MSG_DEBUG, "TLSv1: Failed to create a record"); tls_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_INTERNAL_ERROR); return -1; } return rlen; } /** * tlsv1_client_decrypt - Decrypt data from TLS tunnel * @conn: TLSv1 client connection data from tlsv1_client_init() * @in_data: Pointer to input buffer (encrypted TLS data) * @in_len: Input buffer length * @need_more_data: Set to 1 if more data would be needed to complete * processing * Returns: Decrypted data or %NULL on failure * * This function is used after TLS handshake has been completed successfully to * receive data from the encrypted tunnel. */ struct wpabuf * tlsv1_client_decrypt(struct tlsv1_client *conn, const u8 *in_data, size_t in_len, int *need_more_data) { const u8 *in_end, *pos; int used; u8 alert, *out_pos, ct; size_t olen; struct wpabuf *buf = NULL; if (need_more_data) *need_more_data = 0; if (conn->partial_input) { if (wpabuf_resize(&conn->partial_input, in_len) < 0) { wpa_printf(MSG_DEBUG, "TLSv1: Failed to allocate " "memory for pending record"); alert = TLS_ALERT_INTERNAL_ERROR; goto fail; } wpabuf_put_data(conn->partial_input, in_data, in_len); in_data = wpabuf_head(conn->partial_input); in_len = wpabuf_len(conn->partial_input); } pos = in_data; in_end = in_data + in_len; while (pos < in_end) { ct = pos[0]; if (wpabuf_resize(&buf, in_end - pos) < 0) { alert = TLS_ALERT_INTERNAL_ERROR; goto fail; } out_pos = wpabuf_put(buf, 0); olen = wpabuf_tailroom(buf); used = tlsv1_record_receive(&conn->rl, pos, in_end - pos, out_pos, &olen, &alert); if (used < 0) { wpa_printf(MSG_DEBUG, "TLSv1: Record layer processing " "failed"); goto fail; } if (used == 0) { struct wpabuf *partial; wpa_printf(MSG_DEBUG, "TLSv1: Need more data"); partial = wpabuf_alloc_copy(pos, in_end - pos); wpabuf_free(conn->partial_input); conn->partial_input = partial; if (conn->partial_input == NULL) { wpa_printf(MSG_DEBUG, "TLSv1: Failed to " "allocate memory for pending " "record"); alert = TLS_ALERT_INTERNAL_ERROR; goto fail; } if (need_more_data) *need_more_data = 1; return buf; } if (ct == TLS_CONTENT_TYPE_ALERT) { if (olen < 2) { wpa_printf(MSG_DEBUG, "TLSv1: Alert " "underflow"); alert = TLS_ALERT_DECODE_ERROR; goto fail; } wpa_printf(MSG_DEBUG, "TLSv1: Received alert %d:%d", out_pos[0], out_pos[1]); if (out_pos[0] == TLS_ALERT_LEVEL_WARNING) { /* Continue processing */ pos += used; continue; } alert = out_pos[1]; goto fail; } if (ct != TLS_CONTENT_TYPE_APPLICATION_DATA) { wpa_printf(MSG_DEBUG, "TLSv1: Unexpected content type " "0x%x when decrypting application data", pos[0]); alert = TLS_ALERT_UNEXPECTED_MESSAGE; goto fail; } wpabuf_put(buf, olen); pos += used; } wpabuf_free(conn->partial_input); conn->partial_input = NULL; return buf; fail: wpabuf_free(buf); wpabuf_free(conn->partial_input); conn->partial_input = NULL; tls_alert(conn, TLS_ALERT_LEVEL_FATAL, alert); return NULL; } /** * tlsv1_client_global_init - Initialize TLSv1 client * Returns: 0 on success, -1 on failure * * This function must be called before using any other TLSv1 client functions. */ int tlsv1_client_global_init(void) { return crypto_global_init(); } /** * tlsv1_client_global_deinit - Deinitialize TLSv1 client * * This function can be used to deinitialize the TLSv1 client that was * initialized by calling tlsv1_client_global_init(). No TLSv1 client functions * can be called after this before calling tlsv1_client_global_init() again. */ void tlsv1_client_global_deinit(void) { crypto_global_deinit(); } /** * tlsv1_client_init - Initialize TLSv1 client connection * Returns: Pointer to TLSv1 client connection data or %NULL on failure */ struct tlsv1_client * tlsv1_client_init(void) { struct tlsv1_client *conn; size_t count; u16 *suites; conn = os_zalloc(sizeof(*conn)); if (conn == NULL) return NULL; conn->state = CLIENT_HELLO; if (tls_verify_hash_init(&conn->verify) < 0) { wpa_printf(MSG_DEBUG, "TLSv1: Failed to initialize verify " "hash"); os_free(conn); return NULL; } count = 0; suites = conn->cipher_suites; suites[count++] = TLS_RSA_WITH_AES_256_CBC_SHA256; suites[count++] = TLS_RSA_WITH_AES_256_CBC_SHA; suites[count++] = TLS_RSA_WITH_AES_128_CBC_SHA256; suites[count++] = TLS_RSA_WITH_AES_128_CBC_SHA; suites[count++] = TLS_RSA_WITH_3DES_EDE_CBC_SHA; suites[count++] = TLS_RSA_WITH_RC4_128_SHA; suites[count++] = TLS_RSA_WITH_RC4_128_MD5; conn->num_cipher_suites = count; conn->rl.tls_version = TLS_VERSION; return conn; } /** * tlsv1_client_deinit - Deinitialize TLSv1 client connection * @conn: TLSv1 client connection data from tlsv1_client_init() */ void tlsv1_client_deinit(struct tlsv1_client *conn) { crypto_public_key_free(conn->server_rsa_key); tlsv1_record_set_cipher_suite(&conn->rl, TLS_NULL_WITH_NULL_NULL); tlsv1_record_change_write_cipher(&conn->rl); tlsv1_record_change_read_cipher(&conn->rl); tls_verify_hash_free(&conn->verify); os_free(conn->client_hello_ext); tlsv1_client_free_dh(conn); tlsv1_cred_free(conn->cred); wpabuf_free(conn->partial_input); os_free(conn); } /** * tlsv1_client_established - Check whether connection has been established * @conn: TLSv1 client connection data from tlsv1_client_init() * Returns: 1 if connection is established, 0 if not */ int tlsv1_client_established(struct tlsv1_client *conn) { return conn->state == ESTABLISHED; } /** * tlsv1_client_prf - Use TLS-PRF to derive keying material * @conn: TLSv1 client connection data from tlsv1_client_init() * @label: Label (e.g., description of the key) for PRF * @server_random_first: seed is 0 = client_random|server_random, * 1 = server_random|client_random * @out: Buffer for output data from TLS-PRF * @out_len: Length of the output buffer * Returns: 0 on success, -1 on failure */ int tlsv1_client_prf(struct tlsv1_client *conn, const char *label, int server_random_first, u8 *out, size_t out_len) { u8 seed[2 * TLS_RANDOM_LEN]; if (conn->state != ESTABLISHED) return -1; if (server_random_first) { os_memcpy(seed, conn->server_random, TLS_RANDOM_LEN); os_memcpy(seed + TLS_RANDOM_LEN, conn->client_random, TLS_RANDOM_LEN); } else { os_memcpy(seed, conn->client_random, TLS_RANDOM_LEN); os_memcpy(seed + TLS_RANDOM_LEN, conn->server_random, TLS_RANDOM_LEN); } return tls_prf(conn->rl.tls_version, conn->master_secret, TLS_MASTER_SECRET_LEN, label, seed, 2 * TLS_RANDOM_LEN, out, out_len); } /** * tlsv1_client_get_cipher - Get current cipher name * @conn: TLSv1 client connection data from tlsv1_client_init() * @buf: Buffer for the cipher name * @buflen: buf size * Returns: 0 on success, -1 on failure * * Get the name of the currently used cipher. */ int tlsv1_client_get_cipher(struct tlsv1_client *conn, char *buf, size_t buflen) { char *cipher; switch (conn->rl.cipher_suite) { case TLS_RSA_WITH_RC4_128_MD5: cipher = "RC4-MD5"; break; case TLS_RSA_WITH_RC4_128_SHA: cipher = "RC4-SHA"; break; case TLS_RSA_WITH_DES_CBC_SHA: cipher = "DES-CBC-SHA"; break; case TLS_RSA_WITH_3DES_EDE_CBC_SHA: cipher = "DES-CBC3-SHA"; break; case TLS_DH_anon_WITH_AES_128_CBC_SHA256: cipher = "ADH-AES-128-SHA256"; break; case TLS_DH_anon_WITH_AES_128_CBC_SHA: cipher = "ADH-AES-128-SHA"; break; case TLS_RSA_WITH_AES_256_CBC_SHA: cipher = "AES-256-SHA"; break; case TLS_RSA_WITH_AES_256_CBC_SHA256: cipher = "AES-256-SHA256"; break; case TLS_RSA_WITH_AES_128_CBC_SHA: cipher = "AES-128-SHA"; break; case TLS_RSA_WITH_AES_128_CBC_SHA256: cipher = "AES-128-SHA256"; break; default: return -1; } if (os_strlcpy(buf, cipher, buflen) >= buflen) return -1; return 0; } /** * tlsv1_client_shutdown - Shutdown TLS connection * @conn: TLSv1 client connection data from tlsv1_client_init() * Returns: 0 on success, -1 on failure */ int tlsv1_client_shutdown(struct tlsv1_client *conn) { conn->state = CLIENT_HELLO; if (tls_verify_hash_init(&conn->verify) < 0) { wpa_printf(MSG_DEBUG, "TLSv1: Failed to re-initialize verify " "hash"); return -1; } tlsv1_record_set_cipher_suite(&conn->rl, TLS_NULL_WITH_NULL_NULL); tlsv1_record_change_write_cipher(&conn->rl); tlsv1_record_change_read_cipher(&conn->rl); conn->certificate_requested = 0; crypto_public_key_free(conn->server_rsa_key); conn->server_rsa_key = NULL; conn->session_resumed = 0; return 0; } /** * tlsv1_client_resumed - Was session resumption used * @conn: TLSv1 client connection data from tlsv1_client_init() * Returns: 1 if current session used session resumption, 0 if not */ int tlsv1_client_resumed(struct tlsv1_client *conn) { return !!conn->session_resumed; } /** * tlsv1_client_hello_ext - Set TLS extension for ClientHello * @conn: TLSv1 client connection data from tlsv1_client_init() * @ext_type: Extension type * @data: Extension payload (%NULL to remove extension) * @data_len: Extension payload length * Returns: 0 on success, -1 on failure */ int tlsv1_client_hello_ext(struct tlsv1_client *conn, int ext_type, const u8 *data, size_t data_len) { u8 *pos; conn->session_ticket_included = 0; os_free(conn->client_hello_ext); conn->client_hello_ext = NULL; conn->client_hello_ext_len = 0; if (data == NULL || data_len == 0) return 0; pos = conn->client_hello_ext = os_malloc(6 + data_len); if (pos == NULL) return -1; WPA_PUT_BE16(pos, 4 + data_len); pos += 2; WPA_PUT_BE16(pos, ext_type); pos += 2; WPA_PUT_BE16(pos, data_len); pos += 2; os_memcpy(pos, data, data_len); conn->client_hello_ext_len = 6 + data_len; if (ext_type == TLS_EXT_PAC_OPAQUE) { conn->session_ticket_included = 1; wpa_printf(MSG_DEBUG, "TLSv1: Using session ticket"); } return 0; } /** * tlsv1_client_get_keys - Get master key and random data from TLS connection * @conn: TLSv1 client connection data from tlsv1_client_init() * @keys: Structure of key/random data (filled on success) * Returns: 0 on success, -1 on failure */ int tlsv1_client_get_keys(struct tlsv1_client *conn, struct tls_keys *keys) { os_memset(keys, 0, sizeof(*keys)); if (conn->state == CLIENT_HELLO) return -1; keys->client_random = conn->client_random; keys->client_random_len = TLS_RANDOM_LEN; if (conn->state != SERVER_HELLO) { keys->server_random = conn->server_random; keys->server_random_len = TLS_RANDOM_LEN; keys->master_key = conn->master_secret; keys->master_key_len = TLS_MASTER_SECRET_LEN; } return 0; } /** * tlsv1_client_get_keyblock_size - Get TLS key_block size * @conn: TLSv1 client connection data from tlsv1_client_init() * Returns: Size of the key_block for the negotiated cipher suite or -1 on * failure */ int tlsv1_client_get_keyblock_size(struct tlsv1_client *conn) { if (conn->state == CLIENT_HELLO || conn->state == SERVER_HELLO) return -1; return 2 * (conn->rl.hash_size + conn->rl.key_material_len + conn->rl.iv_size); } /** * tlsv1_client_set_cipher_list - Configure acceptable cipher suites * @conn: TLSv1 client connection data from tlsv1_client_init() * @ciphers: Zero (TLS_CIPHER_NONE) terminated list of allowed ciphers * (TLS_CIPHER_*). * Returns: 0 on success, -1 on failure */ int tlsv1_client_set_cipher_list(struct tlsv1_client *conn, u8 *ciphers) { size_t count; u16 *suites; /* TODO: implement proper configuration of cipher suites */ if (ciphers[0] == TLS_CIPHER_ANON_DH_AES128_SHA) { count = 0; suites = conn->cipher_suites; suites[count++] = TLS_DH_anon_WITH_AES_256_CBC_SHA256; suites[count++] = TLS_DH_anon_WITH_AES_256_CBC_SHA; suites[count++] = TLS_DH_anon_WITH_AES_128_CBC_SHA256; suites[count++] = TLS_DH_anon_WITH_AES_128_CBC_SHA; suites[count++] = TLS_DH_anon_WITH_3DES_EDE_CBC_SHA; suites[count++] = TLS_DH_anon_WITH_RC4_128_MD5; suites[count++] = TLS_DH_anon_WITH_DES_CBC_SHA; /* * Cisco AP (at least 350 and 1200 series) local authentication * server does not know how to search cipher suites from the * list and seem to require that the last entry in the list is * the one that it wants to use. However, TLS specification * requires the list to be in the client preference order. As a * workaround, add anon-DH AES-128-SHA1 again at the end of the * list to allow the Cisco code to find it. */ suites[count++] = TLS_DH_anon_WITH_AES_128_CBC_SHA; conn->num_cipher_suites = count; } return 0; } /** * tlsv1_client_set_cred - Set client credentials * @conn: TLSv1 client connection data from tlsv1_client_init() * @cred: Credentials from tlsv1_cred_alloc() * Returns: 0 on success, -1 on failure * * On success, the client takes ownership of the credentials block and caller * must not free it. On failure, caller is responsible for freeing the * credential block. */ int tlsv1_client_set_cred(struct tlsv1_client *conn, struct tlsv1_credentials *cred) { tlsv1_cred_free(conn->cred); conn->cred = cred; return 0; } void tlsv1_client_set_time_checks(struct tlsv1_client *conn, int enabled) { conn->disable_time_checks = !enabled; } void tlsv1_client_set_session_ticket_cb(struct tlsv1_client *conn, tlsv1_client_session_ticket_cb cb, void *ctx) { wpa_printf(MSG_DEBUG, "TLSv1: SessionTicket callback set %p (ctx %p)", cb, ctx); conn->session_ticket_cb = cb; conn->session_ticket_cb_ctx = ctx; }