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) { wpa_printf(MSG_DEBUG, "TLSv1: Alert underflow"); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_DECODE_ERROR); return -1; } wpa_printf(MSG_DEBUG, "TLSv1: 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: wpa_printf(MSG_DEBUG, "TLSv1: 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; }
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, buflen; u8 hash[MD5_MAC_LEN + SHA1_MAC_LEN], *hpos, *buf; enum { SIGN_ALG_RSA, SIGN_ALG_DSA } alg = SIGN_ALG_RSA; u16 slen; if (ct == TLS_CONTENT_TYPE_CHANGE_CIPHER_SPEC) { if (conn->verify_peer) { wpa_printf(MSG_DEBUG, "TLSv1: 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) { wpa_printf(MSG_DEBUG, "TLSv1: 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) { wpa_printf(MSG_DEBUG, "TLSv1: 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) { wpa_printf(MSG_DEBUG, "TLSv1: 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) { wpa_printf(MSG_DEBUG, "TLSv1: Received unexpected handshake " "message %d (expected CertificateVerify)", type); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_UNEXPECTED_MESSAGE); return -1; } wpa_printf(MSG_DEBUG, "TLSv1: Received CertificateVerify"); /* * struct { * Signature signature; * } CertificateVerify; */ hpos = hash; 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; wpa_hexdump(MSG_MSGDUMP, "TLSv1: CertificateVerify hash", hash, hlen); if (end - pos < 2) { tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_DECODE_ERROR); return -1; } slen = WPA_GET_BE16(pos); pos += 2; if (end - pos < slen) { tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_DECODE_ERROR); return -1; } wpa_hexdump(MSG_MSGDUMP, "TLSv1: Signature", pos, end - pos); if (conn->client_rsa_key == NULL) { wpa_printf(MSG_DEBUG, "TLSv1: No client public key to verify " "signature"); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_INTERNAL_ERROR); return -1; } buflen = end - pos; buf = os_malloc(end - pos); if (crypto_public_key_decrypt_pkcs1(conn->client_rsa_key, pos, end - pos, buf, &buflen) < 0) { wpa_printf(MSG_DEBUG, "TLSv1: Failed to decrypt signature"); os_free(buf); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_DECRYPT_ERROR); return -1; } wpa_hexdump_key(MSG_MSGDUMP, "TLSv1: Decrypted Signature", buf, buflen); if (buflen != hlen || os_memcmp(buf, hash, buflen) != 0) { wpa_printf(MSG_DEBUG, "TLSv1: Invalid Signature in " "CertificateVerify - did not match with calculated " "hash"); os_free(buf); tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_DECRYPT_ERROR); return -1; } os_free(buf); *in_len = end - in_data; conn->state = CHANGE_CIPHER_SPEC; return 0; }