/* * TLSv1 server - read handshake message * Copyright (c) 2006-2014, 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/md5.h" #include "crypto/sha1.h" #include "crypto/sha256.h" #include "crypto/tls.h" #include "x509v3.h" #include "tlsv1_common.h" #include "tlsv1_record.h" #include "tlsv1_server.h" #include "tlsv1_server_i.h" static int tls_process_client_key_exchange(struct tlsv1_server *conn, u8 ct, const u8 *in_data, size_t *in_len); static int tls_process_change_cipher_spec(struct tlsv1_server *conn, u8 ct, const u8 *in_data, size_t *in_len); static int testing_cipher_suite_filter(struct tlsv1_server *conn, u16 suite) { #ifdef CONFIG_TESTING_OPTIONS if ((conn->test_flags & (TLS_BREAK_SRV_KEY_X_HASH | TLS_BREAK_SRV_KEY_X_SIGNATURE | TLS_DHE_PRIME_511B | TLS_DHE_PRIME_767B | TLS_DHE_PRIME_15 | TLS_DHE_PRIME_58B | TLS_DHE_NON_PRIME)) && suite != TLS_DHE_RSA_WITH_AES_256_CBC_SHA256 && suite != TLS_DHE_RSA_WITH_AES_256_CBC_SHA && suite != TLS_DHE_RSA_WITH_AES_128_CBC_SHA256 && suite != TLS_DHE_RSA_WITH_AES_128_CBC_SHA && suite != TLS_DHE_RSA_WITH_3DES_EDE_CBC_SHA) return 1; #endif /* CONFIG_TESTING_OPTIONS */ return 0; } static int tls_process_client_hello(struct tlsv1_server *conn, u8 ct, const u8 *in_data, size_t *in_len) { const u8 *pos, *end, *c; size_t left, len, i, j; u16 cipher_suite; u16 num_suites; int compr_null_found; u16 ext_type, ext_len; if (ct != TLS_CONTENT_TYPE_HANDSHAKE) { tlsv1_server_log(conn, "Expected Handshake; received content type 0x%x", ct); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_UNEXPECTED_MESSAGE); return -1; } pos = in_data; left = *in_len; if (left < 4) goto decode_error; /* HandshakeType msg_type */ if (*pos != TLS_HANDSHAKE_TYPE_CLIENT_HELLO) { tlsv1_server_log(conn, "Received unexpected handshake message %d (expected ClientHello)", *pos); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_UNEXPECTED_MESSAGE); return -1; } tlsv1_server_log(conn, "Received ClientHello"); pos++; /* uint24 length */ len = WPA_GET_BE24(pos); pos += 3; left -= 4; if (len > left) goto decode_error; /* body - ClientHello */ wpa_hexdump(MSG_MSGDUMP, "TLSv1: ClientHello", pos, len); end = pos + len; /* ProtocolVersion client_version */ if (end - pos < 2) goto decode_error; conn->client_version = WPA_GET_BE16(pos); tlsv1_server_log(conn, "Client version %d.%d", conn->client_version >> 8, conn->client_version & 0xff); if (conn->client_version < TLS_VERSION_1) { tlsv1_server_log(conn, "Unexpected protocol version in ClientHello %u.%u", conn->client_version >> 8, conn->client_version & 0xff); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_PROTOCOL_VERSION); return -1; } pos += 2; if (TLS_VERSION == TLS_VERSION_1) conn->rl.tls_version = TLS_VERSION_1; #ifdef CONFIG_TLSV12 else if (conn->client_version >= TLS_VERSION_1_2) conn->rl.tls_version = TLS_VERSION_1_2; #endif /* CONFIG_TLSV12 */ else if (conn->client_version > TLS_VERSION_1_1) conn->rl.tls_version = TLS_VERSION_1_1; else conn->rl.tls_version = conn->client_version; tlsv1_server_log(conn, "Using TLS v%s", tls_version_str(conn->rl.tls_version)); /* Random random */ if (end - pos < TLS_RANDOM_LEN) goto decode_error; os_memcpy(conn->client_random, pos, TLS_RANDOM_LEN); pos += TLS_RANDOM_LEN; wpa_hexdump(MSG_MSGDUMP, "TLSv1: client_random", conn->client_random, TLS_RANDOM_LEN); /* SessionID session_id */ if (end - pos < 1) goto decode_error; if (end - pos < 1 + *pos || *pos > TLS_SESSION_ID_MAX_LEN) goto decode_error; wpa_hexdump(MSG_MSGDUMP, "TLSv1: client session_id", pos + 1, *pos); pos += 1 + *pos; /* TODO: add support for session resumption */ /* CipherSuite cipher_suites<2..2^16-1> */ if (end - pos < 2) goto decode_error; num_suites = WPA_GET_BE16(pos); pos += 2; if (end - pos < num_suites) goto decode_error; wpa_hexdump(MSG_MSGDUMP, "TLSv1: client cipher suites", pos, num_suites); if (num_suites & 1) goto decode_error; num_suites /= 2; cipher_suite = 0; for (i = 0; !cipher_suite && i < conn->num_cipher_suites; i++) { if (testing_cipher_suite_filter(conn, conn->cipher_suites[i])) continue; c = pos; for (j = 0; j < num_suites; j++) { u16 tmp = WPA_GET_BE16(c); c += 2; if (!cipher_suite && tmp == conn->cipher_suites[i]) { cipher_suite = tmp; break; } } } pos += num_suites * 2; if (!cipher_suite) { tlsv1_server_log(conn, "No supported cipher suite available"); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_ILLEGAL_PARAMETER); return -1; } if (tlsv1_record_set_cipher_suite(&conn->rl, cipher_suite) < 0) { wpa_printf(MSG_DEBUG, "TLSv1: Failed to set CipherSuite for " "record layer"); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_INTERNAL_ERROR); return -1; } conn->cipher_suite = cipher_suite; /* CompressionMethod compression_methods<1..2^8-1> */ if (end - pos < 1) goto decode_error; num_suites = *pos++; if (end - pos < num_suites) goto decode_error; wpa_hexdump(MSG_MSGDUMP, "TLSv1: client compression_methods", pos, num_suites); compr_null_found = 0; for (i = 0; i < num_suites; i++) { if (*pos++ == TLS_COMPRESSION_NULL) compr_null_found = 1; } if (!compr_null_found) { tlsv1_server_log(conn, "Client does not accept NULL compression"); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_ILLEGAL_PARAMETER); return -1; } if (end - pos == 1) { tlsv1_server_log(conn, "Unexpected extra octet in the end of ClientHello: 0x%02x", *pos); goto decode_error; } if (end - pos >= 2) { /* Extension client_hello_extension_list<0..2^16-1> */ ext_len = WPA_GET_BE16(pos); pos += 2; tlsv1_server_log(conn, "%u bytes of ClientHello extensions", ext_len); if (end - pos != ext_len) { tlsv1_server_log(conn, "Invalid ClientHello extension list length %u (expected %u)", ext_len, (unsigned int) (end - pos)); goto decode_error; } /* * struct { * ExtensionType extension_type (0..65535) * opaque extension_data<0..2^16-1> * } Extension; */ while (pos < end) { if (end - pos < 2) { tlsv1_server_log(conn, "Invalid extension_type field"); goto decode_error; } ext_type = WPA_GET_BE16(pos); pos += 2; if (end - pos < 2) { tlsv1_server_log(conn, "Invalid extension_data length field"); goto decode_error; } ext_len = WPA_GET_BE16(pos); pos += 2; if (end - pos < ext_len) { tlsv1_server_log(conn, "Invalid extension_data field"); goto decode_error; } tlsv1_server_log(conn, "ClientHello Extension type %u", ext_type); wpa_hexdump(MSG_MSGDUMP, "TLSv1: ClientHello " "Extension data", pos, ext_len); if (ext_type == TLS_EXT_SESSION_TICKET) { os_free(conn->session_ticket); conn->session_ticket = os_malloc(ext_len); if (conn->session_ticket) { os_memcpy(conn->session_ticket, pos, ext_len); conn->session_ticket_len = ext_len; } } pos += ext_len; } } *in_len = end - in_data; tlsv1_server_log(conn, "ClientHello OK - proceed to ServerHello"); conn->state = SERVER_HELLO; return 0; decode_error: tlsv1_server_log(conn, "Failed to decode ClientHello"); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_DECODE_ERROR); return -1; } static int tls_process_certificate(struct tlsv1_server *conn, u8 ct, const u8 *in_data, size_t *in_len) { const u8 *pos, *end; size_t left, len, list_len, cert_len, idx; u8 type; struct x509_certificate *chain = NULL, *last = NULL, *cert; int reason; if (ct != TLS_CONTENT_TYPE_HANDSHAKE) { tlsv1_server_log(conn, "Expected Handshake; received content type 0x%x", ct); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_UNEXPECTED_MESSAGE); return -1; } pos = in_data; left = *in_len; if (left < 4) { tlsv1_server_log(conn, "Too short Certificate message (len=%lu)", (unsigned long) left); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_DECODE_ERROR); return -1; } type = *pos++; len = WPA_GET_BE24(pos); pos += 3; left -= 4; if (len > left) { tlsv1_server_log(conn, "Unexpected Certificate message length (len=%lu != left=%lu)", (unsigned long) len, (unsigned long) left); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_DECODE_ERROR); return -1; } if (type == TLS_HANDSHAKE_TYPE_CLIENT_KEY_EXCHANGE) { if (conn->verify_peer) { tlsv1_server_log(conn, "Client did not include Certificate"); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_UNEXPECTED_MESSAGE); return -1; } return tls_process_client_key_exchange(conn, ct, in_data, in_len); } if (type != TLS_HANDSHAKE_TYPE_CERTIFICATE) { tlsv1_server_log(conn, "Received unexpected handshake message %d (expected Certificate/ClientKeyExchange)", type); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_UNEXPECTED_MESSAGE); return -1; } tlsv1_server_log(conn, "Received Certificate (certificate_list len %lu)", (unsigned long) len); /* * opaque ASN.1Cert<2^24-1>; * * struct { * ASN.1Cert certificate_list<1..2^24-1>; * } Certificate; */ end = pos + len; if (end - pos < 3) { tlsv1_server_log(conn, "Too short Certificate (left=%lu)", (unsigned long) left); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_DECODE_ERROR); return -1; } list_len = WPA_GET_BE24(pos); pos += 3; if ((size_t) (end - pos) != list_len) { tlsv1_server_log(conn, "Unexpected certificate_list length (len=%lu left=%lu)", (unsigned long) list_len, (unsigned long) (end - pos)); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_DECODE_ERROR); return -1; } idx = 0; while (pos < end) { if (end - pos < 3) { tlsv1_server_log(conn, "Failed to parse certificate_list"); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_DECODE_ERROR); x509_certificate_chain_free(chain); return -1; } cert_len = WPA_GET_BE24(pos); pos += 3; if ((size_t) (end - pos) < cert_len) { tlsv1_server_log(conn, "Unexpected certificate length (len=%lu left=%lu)", (unsigned long) cert_len, (unsigned long) (end - pos)); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_DECODE_ERROR); x509_certificate_chain_free(chain); return -1; } tlsv1_server_log(conn, "Certificate %lu (len %lu)", (unsigned long) idx, (unsigned long) cert_len); if (idx == 0) { crypto_public_key_free(conn->client_rsa_key); if (tls_parse_cert(pos, cert_len, &conn->client_rsa_key)) { tlsv1_server_log(conn, "Failed to parse the certificate"); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_BAD_CERTIFICATE); x509_certificate_chain_free(chain); return -1; } } cert = x509_certificate_parse(pos, cert_len); if (cert == NULL) { tlsv1_server_log(conn, "Failed to parse the certificate"); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_BAD_CERTIFICATE); x509_certificate_chain_free(chain); return -1; } if (last == NULL) chain = cert; else last->next = cert; last = cert; idx++; pos += cert_len; } if (x509_certificate_chain_validate(conn->cred->trusted_certs, chain, &reason, 0) < 0) { int tls_reason; tlsv1_server_log(conn, "Server certificate chain validation failed (reason=%d)", reason); switch (reason) { case X509_VALIDATE_BAD_CERTIFICATE: tls_reason = TLS_ALERT_BAD_CERTIFICATE; break; case X509_VALIDATE_UNSUPPORTED_CERTIFICATE: tls_reason = TLS_ALERT_UNSUPPORTED_CERTIFICATE; break; case X509_VALIDATE_CERTIFICATE_REVOKED: tls_reason = TLS_ALERT_CERTIFICATE_REVOKED; break; case X509_VALIDATE_CERTIFICATE_EXPIRED: tls_reason = TLS_ALERT_CERTIFICATE_EXPIRED; break; case X509_VALIDATE_CERTIFICATE_UNKNOWN: tls_reason = TLS_ALERT_CERTIFICATE_UNKNOWN; break; case X509_VALIDATE_UNKNOWN_CA: tls_reason = TLS_ALERT_UNKNOWN_CA; break; default: tls_reason = TLS_ALERT_BAD_CERTIFICATE; break; } tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, tls_reason); x509_certificate_chain_free(chain); return -1; } x509_certificate_chain_free(chain); *in_len = end - in_data; conn->state = CLIENT_KEY_EXCHANGE; return 0; } static int tls_process_client_key_exchange_rsa( struct tlsv1_server *conn, const u8 *pos, const u8 *end) { u8 *out; size_t outlen, outbuflen; u16 encr_len; int res; int use_random = 0; if (end - pos < 2) { tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_DECODE_ERROR); return -1; } encr_len = WPA_GET_BE16(pos); pos += 2; if (pos + encr_len > end) { tlsv1_server_log(conn, "Invalid ClientKeyExchange format: encr_len=%u left=%u", encr_len, (unsigned int) (end - pos)); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_DECODE_ERROR); return -1; } outbuflen = outlen = end - pos; out = os_malloc(outlen >= TLS_PRE_MASTER_SECRET_LEN ? outlen : TLS_PRE_MASTER_SECRET_LEN); if (out == NULL) { tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_INTERNAL_ERROR); return -1; } /* * struct { * ProtocolVersion client_version; * opaque random[46]; * } PreMasterSecret; * * struct { * public-key-encrypted PreMasterSecret pre_master_secret; * } EncryptedPreMasterSecret; */ /* * Note: To avoid Bleichenbacher attack, we do not report decryption or * parsing errors from EncryptedPreMasterSecret processing to the * client. Instead, a random pre-master secret is used to force the * handshake to fail. */ if (crypto_private_key_decrypt_pkcs1_v15(conn->cred->key, pos, encr_len, out, &outlen) < 0) { wpa_printf(MSG_DEBUG, "TLSv1: Failed to decrypt " "PreMasterSecret (encr_len=%u outlen=%lu)", encr_len, (unsigned long) outlen); use_random = 1; } if (!use_random && outlen != TLS_PRE_MASTER_SECRET_LEN) { tlsv1_server_log(conn, "Unexpected PreMasterSecret length %lu", (unsigned long) outlen); use_random = 1; } if (!use_random && WPA_GET_BE16(out) != conn->client_version) { tlsv1_server_log(conn, "Client version in ClientKeyExchange does not match with version in ClientHello"); use_random = 1; } if (use_random) { wpa_printf(MSG_DEBUG, "TLSv1: Using random premaster secret " "to avoid revealing information about private key"); outlen = TLS_PRE_MASTER_SECRET_LEN; if (os_get_random(out, outlen)) { wpa_printf(MSG_DEBUG, "TLSv1: Failed to get random " "data"); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_INTERNAL_ERROR); os_free(out); return -1; } } res = tlsv1_server_derive_keys(conn, out, outlen); /* Clear the pre-master secret since it is not needed anymore */ os_memset(out, 0, outbuflen); os_free(out); if (res) { wpa_printf(MSG_DEBUG, "TLSv1: Failed to derive keys"); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_INTERNAL_ERROR); return -1; } return 0; } static int tls_process_client_key_exchange_dh( struct tlsv1_server *conn, const u8 *pos, const u8 *end) { const u8 *dh_yc; u16 dh_yc_len; u8 *shared; size_t shared_len; int res; const u8 *dh_p; size_t dh_p_len; /* * struct { * select (PublicValueEncoding) { * case implicit: struct { }; * case explicit: opaque dh_Yc<1..2^16-1>; * } dh_public; * } ClientDiffieHellmanPublic; */ tlsv1_server_log(conn, "ClientDiffieHellmanPublic received"); wpa_hexdump(MSG_MSGDUMP, "TLSv1: ClientDiffieHellmanPublic", pos, end - pos); if (end == pos) { wpa_printf(MSG_DEBUG, "TLSv1: Implicit public value encoding " "not supported"); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_INTERNAL_ERROR); return -1; } if (end - pos < 3) { tlsv1_server_log(conn, "Invalid client public value length"); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_DECODE_ERROR); return -1; } dh_yc_len = WPA_GET_BE16(pos); dh_yc = pos + 2; if (dh_yc + dh_yc_len > end) { tlsv1_server_log(conn, "Client public value overflow (length %d)", dh_yc_len); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_DECODE_ERROR); return -1; } wpa_hexdump(MSG_DEBUG, "TLSv1: DH Yc (client's public value)", dh_yc, dh_yc_len); if (conn->cred == NULL || conn->cred->dh_p == NULL || conn->dh_secret == NULL) { wpa_printf(MSG_DEBUG, "TLSv1: No DH parameters available"); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_INTERNAL_ERROR); return -1; } tlsv1_server_get_dh_p(conn, &dh_p, &dh_p_len); shared_len = dh_p_len; shared = os_malloc(shared_len); if (shared == NULL) { wpa_printf(MSG_DEBUG, "TLSv1: Could not allocate memory for " "DH"); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_INTERNAL_ERROR); return -1; } /* shared = Yc^secret mod p */ if (crypto_mod_exp(dh_yc, dh_yc_len, conn->dh_secret, conn->dh_secret_len, dh_p, dh_p_len, shared, &shared_len)) { os_free(shared); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_INTERNAL_ERROR); return -1; } wpa_hexdump_key(MSG_DEBUG, "TLSv1: Shared secret from DH key exchange", shared, shared_len); os_memset(conn->dh_secret, 0, conn->dh_secret_len); os_free(conn->dh_secret); conn->dh_secret = NULL; res = tlsv1_server_derive_keys(conn, shared, shared_len); /* Clear the pre-master secret since it is not needed anymore */ os_memset(shared, 0, shared_len); os_free(shared); if (res) { wpa_printf(MSG_DEBUG, "TLSv1: Failed to derive keys"); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_INTERNAL_ERROR); return -1; } return 0; } static int tls_process_client_key_exchange(struct tlsv1_server *conn, u8 ct, const u8 *in_data, size_t *in_len) { const u8 *pos, *end; size_t left, len; u8 type; tls_key_exchange keyx; const struct tls_cipher_suite *suite; if (ct != TLS_CONTENT_TYPE_HANDSHAKE) { tlsv1_server_log(conn, "Expected Handshake; received content type 0x%x", ct); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_UNEXPECTED_MESSAGE); return -1; } pos = in_data; left = *in_len; if (left < 4) { tlsv1_server_log(conn, "Too short ClientKeyExchange (Left=%lu)", (unsigned long) left); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_DECODE_ERROR); return -1; } type = *pos++; len = WPA_GET_BE24(pos); pos += 3; left -= 4; if (len > left) { tlsv1_server_log(conn, "Mismatch in ClientKeyExchange length (len=%lu != left=%lu)", (unsigned long) len, (unsigned long) left); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_DECODE_ERROR); return -1; } end = pos + len; if (type != TLS_HANDSHAKE_TYPE_CLIENT_KEY_EXCHANGE) { tlsv1_server_log(conn, "Received unexpected handshake message %d (expected ClientKeyExchange)", type); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_UNEXPECTED_MESSAGE); return -1; } tlsv1_server_log(conn, "Received ClientKeyExchange"); wpa_hexdump(MSG_DEBUG, "TLSv1: ClientKeyExchange", pos, len); suite = tls_get_cipher_suite(conn->rl.cipher_suite); if (suite == NULL) keyx = TLS_KEY_X_NULL; else keyx = suite->key_exchange; if ((keyx == TLS_KEY_X_DH_anon || keyx == TLS_KEY_X_DHE_RSA) && tls_process_client_key_exchange_dh(conn, pos, end) < 0) return -1; if (keyx != TLS_KEY_X_DH_anon && keyx != TLS_KEY_X_DHE_RSA && tls_process_client_key_exchange_rsa(conn, pos, end) < 0) return -1; *in_len = end - in_data; conn->state = CERTIFICATE_VERIFY; return 0; } static int tls_process_certificate_verify(struct tlsv1_server *conn, u8 ct, const u8 *in_data, size_t *in_len) { const u8 *pos, *end; size_t left, len; u8 type; size_t hlen; u8 hash[MD5_MAC_LEN + SHA1_MAC_LEN], *hpos; enum { SIGN_ALG_RSA, SIGN_ALG_DSA } alg = SIGN_ALG_RSA; u8 alert; if (ct == TLS_CONTENT_TYPE_CHANGE_CIPHER_SPEC) { if (conn->verify_peer) { tlsv1_server_log(conn, "Client did not include CertificateVerify"); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_UNEXPECTED_MESSAGE); return -1; } return tls_process_change_cipher_spec(conn, ct, in_data, in_len); } if (ct != TLS_CONTENT_TYPE_HANDSHAKE) { tlsv1_server_log(conn, "Expected Handshake; received content type 0x%x", ct); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_UNEXPECTED_MESSAGE); return -1; } pos = in_data; left = *in_len; if (left < 4) { tlsv1_server_log(conn, "Too short CertificateVerify message (len=%lu)", (unsigned long) left); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_DECODE_ERROR); return -1; } type = *pos++; len = WPA_GET_BE24(pos); pos += 3; left -= 4; if (len > left) { tlsv1_server_log(conn, "Unexpected CertificateVerify message length (len=%lu != left=%lu)", (unsigned long) len, (unsigned long) left); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_DECODE_ERROR); return -1; } end = pos + len; if (type != TLS_HANDSHAKE_TYPE_CERTIFICATE_VERIFY) { tlsv1_server_log(conn, "Received unexpected handshake message %d (expected CertificateVerify)", type); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_UNEXPECTED_MESSAGE); return -1; } tlsv1_server_log(conn, "Received CertificateVerify"); /* * struct { * Signature signature; * } CertificateVerify; */ hpos = hash; #ifdef CONFIG_TLSV12 if (conn->rl.tls_version == TLS_VERSION_1_2) { /* * RFC 5246, 4.7: * TLS v1.2 adds explicit indication of the used signature and * hash algorithms. * * struct { * HashAlgorithm hash; * SignatureAlgorithm signature; * } SignatureAndHashAlgorithm; */ if (end - pos < 2) { tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_DECODE_ERROR); return -1; } if (pos[0] != TLS_HASH_ALG_SHA256 || pos[1] != TLS_SIGN_ALG_RSA) { wpa_printf(MSG_DEBUG, "TLSv1.2: Unsupported hash(%u)/" "signature(%u) algorithm", pos[0], pos[1]); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_INTERNAL_ERROR); return -1; } pos += 2; hlen = SHA256_MAC_LEN; if (conn->verify.sha256_cert == NULL || crypto_hash_finish(conn->verify.sha256_cert, hpos, &hlen) < 0) { conn->verify.sha256_cert = NULL; tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_INTERNAL_ERROR); return -1; } conn->verify.sha256_cert = NULL; } else { #endif /* CONFIG_TLSV12 */ if (alg == SIGN_ALG_RSA) { hlen = MD5_MAC_LEN; if (conn->verify.md5_cert == NULL || crypto_hash_finish(conn->verify.md5_cert, hpos, &hlen) < 0) { tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_INTERNAL_ERROR); conn->verify.md5_cert = NULL; crypto_hash_finish(conn->verify.sha1_cert, NULL, NULL); conn->verify.sha1_cert = NULL; return -1; } hpos += MD5_MAC_LEN; } else crypto_hash_finish(conn->verify.md5_cert, NULL, NULL); conn->verify.md5_cert = NULL; hlen = SHA1_MAC_LEN; if (conn->verify.sha1_cert == NULL || crypto_hash_finish(conn->verify.sha1_cert, hpos, &hlen) < 0) { conn->verify.sha1_cert = NULL; tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_INTERNAL_ERROR); return -1; } conn->verify.sha1_cert = NULL; if (alg == SIGN_ALG_RSA) hlen += MD5_MAC_LEN; #ifdef CONFIG_TLSV12 } #endif /* CONFIG_TLSV12 */ wpa_hexdump(MSG_MSGDUMP, "TLSv1: CertificateVerify hash", hash, hlen); if (tls_verify_signature(conn->rl.tls_version, conn->client_rsa_key, hash, hlen, pos, end - pos, &alert) < 0) { tlsv1_server_log(conn, "Invalid Signature in CertificateVerify"); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, alert); return -1; } *in_len = end - in_data; conn->state = CHANGE_CIPHER_SPEC; return 0; } static int tls_process_change_cipher_spec(struct tlsv1_server *conn, u8 ct, const u8 *in_data, size_t *in_len) { const u8 *pos; size_t left; if (ct != TLS_CONTENT_TYPE_CHANGE_CIPHER_SPEC) { tlsv1_server_log(conn, "Expected ChangeCipherSpec; received content type 0x%x", ct); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_UNEXPECTED_MESSAGE); return -1; } pos = in_data; left = *in_len; if (left < 1) { tlsv1_server_log(conn, "Too short ChangeCipherSpec"); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_DECODE_ERROR); return -1; } if (*pos != TLS_CHANGE_CIPHER_SPEC) { tlsv1_server_log(conn, "Expected ChangeCipherSpec; received data 0x%x", *pos); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_UNEXPECTED_MESSAGE); return -1; } tlsv1_server_log(conn, "Received ChangeCipherSpec"); if (tlsv1_record_change_read_cipher(&conn->rl) < 0) { wpa_printf(MSG_DEBUG, "TLSv1: Failed to change read cipher " "for record layer"); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_INTERNAL_ERROR); return -1; } *in_len = pos + 1 - in_data; conn->state = CLIENT_FINISHED; return 0; } static int tls_process_client_finished(struct tlsv1_server *conn, u8 ct, const u8 *in_data, size_t *in_len) { const u8 *pos, *end; size_t left, len, hlen; u8 verify_data[TLS_VERIFY_DATA_LEN]; u8 hash[MD5_MAC_LEN + SHA1_MAC_LEN]; #ifdef CONFIG_TESTING_OPTIONS if ((conn->test_flags & (TLS_BREAK_SRV_KEY_X_HASH | TLS_BREAK_SRV_KEY_X_SIGNATURE)) && !conn->test_failure_reported) { tlsv1_server_log(conn, "TEST-FAILURE: Client Finished received after invalid ServerKeyExchange"); conn->test_failure_reported = 1; } if ((conn->test_flags & TLS_DHE_PRIME_15) && !conn->test_failure_reported) { tlsv1_server_log(conn, "TEST-FAILURE: Client Finished received after bogus DHE \"prime\" 15"); conn->test_failure_reported = 1; } if ((conn->test_flags & TLS_DHE_PRIME_58B) && !conn->test_failure_reported) { tlsv1_server_log(conn, "TEST-FAILURE: Client Finished received after short 58-bit DHE prime in long container"); conn->test_failure_reported = 1; } if ((conn->test_flags & TLS_DHE_PRIME_511B) && !conn->test_failure_reported) { tlsv1_server_log(conn, "TEST-WARNING: Client Finished received after short 511-bit DHE prime (insecure)"); conn->test_failure_reported = 1; } if ((conn->test_flags & TLS_DHE_PRIME_767B) && !conn->test_failure_reported) { tlsv1_server_log(conn, "TEST-NOTE: Client Finished received after 767-bit DHE prime (relatively insecure)"); conn->test_failure_reported = 1; } if ((conn->test_flags & TLS_DHE_NON_PRIME) && !conn->test_failure_reported) { tlsv1_server_log(conn, "TEST-NOTE: Client Finished received after non-prime claimed as DHE prime"); conn->test_failure_reported = 1; } #endif /* CONFIG_TESTING_OPTIONS */ if (ct != TLS_CONTENT_TYPE_HANDSHAKE) { tlsv1_server_log(conn, "Expected Finished; received content type 0x%x", ct); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_UNEXPECTED_MESSAGE); return -1; } pos = in_data; left = *in_len; if (left < 4) { tlsv1_server_log(conn, "Too short record (left=%lu) forFinished", (unsigned long) left); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_DECODE_ERROR); return -1; } if (pos[0] != TLS_HANDSHAKE_TYPE_FINISHED) { wpa_printf(MSG_DEBUG, "TLSv1: Expected Finished; received " "type 0x%x", pos[0]); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_UNEXPECTED_MESSAGE); return -1; } len = WPA_GET_BE24(pos + 1); pos += 4; left -= 4; if (len > left) { tlsv1_server_log(conn, "Too short buffer for Finished (len=%lu > left=%lu)", (unsigned long) len, (unsigned long) left); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_DECODE_ERROR); return -1; } end = pos + len; if (len != TLS_VERIFY_DATA_LEN) { tlsv1_server_log(conn, "Unexpected verify_data length in Finished: %lu (expected %d)", (unsigned long) len, TLS_VERIFY_DATA_LEN); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_DECODE_ERROR); return -1; } wpa_hexdump(MSG_MSGDUMP, "TLSv1: verify_data in Finished", pos, TLS_VERIFY_DATA_LEN); #ifdef CONFIG_TLSV12 if (conn->rl.tls_version >= TLS_VERSION_1_2) { hlen = SHA256_MAC_LEN; if (conn->verify.sha256_client == NULL || crypto_hash_finish(conn->verify.sha256_client, hash, &hlen) < 0) { tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_INTERNAL_ERROR); conn->verify.sha256_client = NULL; return -1; } conn->verify.sha256_client = NULL; } else { #endif /* CONFIG_TLSV12 */ hlen = MD5_MAC_LEN; if (conn->verify.md5_client == NULL || crypto_hash_finish(conn->verify.md5_client, hash, &hlen) < 0) { tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_INTERNAL_ERROR); conn->verify.md5_client = NULL; crypto_hash_finish(conn->verify.sha1_client, NULL, NULL); conn->verify.sha1_client = NULL; return -1; } conn->verify.md5_client = NULL; hlen = SHA1_MAC_LEN; if (conn->verify.sha1_client == NULL || crypto_hash_finish(conn->verify.sha1_client, hash + MD5_MAC_LEN, &hlen) < 0) { conn->verify.sha1_client = NULL; tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_INTERNAL_ERROR); return -1; } conn->verify.sha1_client = NULL; hlen = MD5_MAC_LEN + SHA1_MAC_LEN; #ifdef CONFIG_TLSV12 } #endif /* CONFIG_TLSV12 */ if (tls_prf(conn->rl.tls_version, conn->master_secret, TLS_MASTER_SECRET_LEN, "client finished", hash, hlen, verify_data, TLS_VERIFY_DATA_LEN)) { wpa_printf(MSG_DEBUG, "TLSv1: Failed to derive verify_data"); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_DECRYPT_ERROR); return -1; } wpa_hexdump_key(MSG_DEBUG, "TLSv1: verify_data (client)", verify_data, TLS_VERIFY_DATA_LEN); if (os_memcmp_const(pos, verify_data, TLS_VERIFY_DATA_LEN) != 0) { tlsv1_server_log(conn, "Mismatch in verify_data"); return -1; } tlsv1_server_log(conn, "Received Finished"); *in_len = end - in_data; if (conn->use_session_ticket) { /* Abbreviated handshake using session ticket; RFC 4507 */ tlsv1_server_log(conn, "Abbreviated handshake completed successfully"); conn->state = ESTABLISHED; } else { /* Full handshake */ conn->state = SERVER_CHANGE_CIPHER_SPEC; } return 0; } int tlsv1_server_process_handshake(struct tlsv1_server *conn, u8 ct, const u8 *buf, size_t *len) { if (ct == TLS_CONTENT_TYPE_ALERT) { if (*len < 2) { tlsv1_server_log(conn, "Alert underflow"); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_DECODE_ERROR); return -1; } tlsv1_server_log(conn, "Received alert %d:%d", buf[0], buf[1]); *len = 2; conn->state = FAILED; return -1; } switch (conn->state) { case CLIENT_HELLO: if (tls_process_client_hello(conn, ct, buf, len)) return -1; break; case CLIENT_CERTIFICATE: if (tls_process_certificate(conn, ct, buf, len)) return -1; break; case CLIENT_KEY_EXCHANGE: if (tls_process_client_key_exchange(conn, ct, buf, len)) return -1; break; case CERTIFICATE_VERIFY: if (tls_process_certificate_verify(conn, ct, buf, len)) return -1; break; case CHANGE_CIPHER_SPEC: if (tls_process_change_cipher_spec(conn, ct, buf, len)) return -1; break; case CLIENT_FINISHED: if (tls_process_client_finished(conn, ct, buf, len)) return -1; break; default: tlsv1_server_log(conn, "Unexpected state %d while processing received message", conn->state); return -1; } if (ct == TLS_CONTENT_TYPE_HANDSHAKE) tls_verify_hash_add(&conn->verify, buf, *len); return 0; }