tlsv1_client.c

WLAN无线网络管理的最新程序

		tls_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);

	/*
	 * RFC 2246, 4.7:
	 * In digital signing, one-way hash functions are used as input for a
	 * signing algorithm. A digitally-signed element is encoded as an
	 * opaque vector <0..2^16-1>, where the length is specified by the
	 * signing algorithm and key.
	 *
	 * In RSA signing, a 36-byte structure of two hashes (one SHA and one
	 * MD5) is signed (encrypted with the private key). It is encoded with
	 * PKCS #1 block type 0 or type 1 as described in [PKCS1].
	 */
	signed_start = pos; /* length to be filled */
	pos += 2;
	clen = end - pos;
	if (crypto_private_key_sign_pkcs1(conn->client_key, hash, hlen,
					  pos, &clen) < 0) {
		wpa_printf(MSG_DEBUG, "TLSv1: Failed to sign hash (PKCS #1)");
		tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
			  TLS_ALERT_INTERNAL_ERROR);
		return -1;
	}
	WPA_PUT_BE16(signed_start, clen);

	pos += clen;

	WPA_PUT_BE24(hs_length, pos - hs_length - 3);

	if (tlsv1_record_send(&conn->rl, TLS_CONTENT_TYPE_HANDSHAKE,
			      rhdr, end - rhdr, pos - hs_start, &rlen) < 0) {
		wpa_printf(MSG_DEBUG, "TLSv1: Failed to generate a record");
		tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
			  TLS_ALERT_INTERNAL_ERROR);
		return -1;
	}
	pos = rhdr + rlen;

	tls_verify_hash_add(conn, hs_start, pos - hs_start);

	*msgpos = pos;

	return 0;
}


static int tls_write_client_change_cipher_spec(struct tlsv1_client *conn,
					       u8 **msgpos, u8 *end)
{
	u8 *pos, *rhdr;
	size_t rlen;

	pos = *msgpos;

	wpa_printf(MSG_DEBUG, "TLSv1: Send ChangeCipherSpec");
	rhdr = pos;
	pos += TLS_RECORD_HEADER_LEN;
	*pos = TLS_CHANGE_CIPHER_SPEC;
	if (tlsv1_record_send(&conn->rl, TLS_CONTENT_TYPE_CHANGE_CIPHER_SPEC,
			      rhdr, end - rhdr, 1, &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;
	}

	if (tlsv1_record_change_write_cipher(&conn->rl) < 0) {
		wpa_printf(MSG_DEBUG, "TLSv1: Failed to set write cipher for "
			   "record layer");
		tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
			  TLS_ALERT_INTERNAL_ERROR);
		return -1;
	}

	*msgpos = rhdr + rlen;

	return 0;
}


static int tls_write_client_finished(struct tlsv1_client *conn,
				     u8 **msgpos, u8 *end)
{
	u8 *pos, *rhdr, *hs_start, *hs_length;
	size_t rlen, hlen;
	u8 verify_data[TLS_VERIFY_DATA_LEN];
	u8 hash[MD5_MAC_LEN + SHA1_MAC_LEN];

	pos = *msgpos;

	wpa_printf(MSG_DEBUG, "TLSv1: Send Finished");

	/* Encrypted Handshake Message: Finished */

	hlen = MD5_MAC_LEN;
	if (conn->verify_md5_client == NULL ||
	    crypto_hash_finish(conn->verify_md5_client, hash, &hlen) < 0) {
		tls_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;
		tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
			  TLS_ALERT_INTERNAL_ERROR);
		return -1;
	}
	conn->verify_sha1_client = NULL;

	if (tls_prf(conn->master_secret, TLS_MASTER_SECRET_LEN,
		    "client finished", hash, MD5_MAC_LEN + SHA1_MAC_LEN,
		    verify_data, TLS_VERIFY_DATA_LEN)) {
		wpa_printf(MSG_DEBUG, "TLSv1: Failed to generate verify_data");
		tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
			  TLS_ALERT_INTERNAL_ERROR);
		return -1;
	}
	wpa_hexdump_key(MSG_DEBUG, "TLSv1: verify_data (client)",
			verify_data, TLS_VERIFY_DATA_LEN);

	rhdr = pos;
	pos += TLS_RECORD_HEADER_LEN;
	/* Handshake */
	hs_start = pos;
	/* HandshakeType msg_type */
	*pos++ = TLS_HANDSHAKE_TYPE_FINISHED;
	/* uint24 length (to be filled) */
	hs_length = pos;
	pos += 3;
	os_memcpy(pos, verify_data, TLS_VERIFY_DATA_LEN);
	pos += TLS_VERIFY_DATA_LEN;
	WPA_PUT_BE24(hs_length, pos - hs_length - 3);
	tls_verify_hash_add(conn, hs_start, pos - hs_start);

	if (tlsv1_record_send(&conn->rl, TLS_CONTENT_TYPE_HANDSHAKE,
			      rhdr, end - rhdr, pos - hs_start, &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;
	}

	pos = rhdr + rlen;

	*msgpos = pos;

	return 0;
}


static size_t tls_client_cert_chain_der_len(struct tlsv1_client *conn)
{
	size_t len = 0;
	struct x509_certificate *cert;

	cert = conn->client_cert;
	while (cert) {
		len += 3 + cert->cert_len;
		if (x509_certificate_self_signed(cert))
			break;
		cert = x509_certificate_get_subject(conn->trusted_certs,
						    &cert->issuer);
	}

	return len;
}


static u8 * tls_send_client_key_exchange(struct tlsv1_client *conn,
					 size_t *out_len)
{
	u8 *msg, *end, *pos;
	size_t msglen;

	*out_len = 0;

	msglen = 1000;
	if (conn->certificate_requested)
		msglen += tls_client_cert_chain_der_len(conn);

	msg = os_malloc(msglen);
	if (msg == NULL)
		return NULL;

	pos = msg;
	end = msg + msglen;

	if (conn->certificate_requested) {
		if (tls_write_client_certificate(conn, &pos, end) < 0) {
			os_free(msg);
			return NULL;
		}
	}

	if (tls_write_client_key_exchange(conn, &pos, end) < 0 ||
	    (conn->certificate_requested && conn->client_key &&
	     tls_write_client_certificate_verify(conn, &pos, end) < 0) ||
	    tls_write_client_change_cipher_spec(conn, &pos, end) < 0 ||
	    tls_write_client_finished(conn, &pos, end) < 0) {
		os_free(msg);
		return NULL;
	}

	*out_len = pos - msg;

	conn->state = SERVER_CHANGE_CIPHER_SPEC;

	return msg;
}


static u8 * tls_send_change_cipher_spec(struct tlsv1_client *conn,
					size_t *out_len)
{
	u8 *msg, *end, *pos;

	*out_len = 0;

	msg = os_malloc(1000);
	if (msg == NULL)
		return NULL;

	pos = msg;
	end = msg + 1000;

	if (tls_write_client_change_cipher_spec(conn, &pos, end) < 0 ||
	    tls_write_client_finished(conn, &pos, end) < 0) {
		os_free(msg);
		return NULL;
	}

	*out_len = pos - msg;

	wpa_printf(MSG_DEBUG, "TLSv1: Session resumption completed "
		   "successfully");
	conn->state = ESTABLISHED;

	return msg;
}


static int tlsv1_client_process_handshake(struct tlsv1_client *conn, u8 ct,
					  const u8 *buf, size_t *len)
{
	if (ct == TLS_CONTENT_TYPE_HANDSHAKE && *len >= 4 &&
	    buf[0] == TLS_HANDSHAKE_TYPE_HELLO_REQUEST) {
		size_t hr_len = WPA_GET_BE24(buf + 1);
		if (hr_len > *len - 4) {
			wpa_printf(MSG_DEBUG, "TLSv1: HelloRequest underflow");
			tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
				  TLS_ALERT_DECODE_ERROR);
			return -1;
		}
		wpa_printf(MSG_DEBUG, "TLSv1: Ignored HelloRequest");
		*len = 4 + hr_len;
		return 0;
	}

	switch (conn->state) {
	case SERVER_HELLO:
		if (tls_process_server_hello(conn, ct, buf, len))
			return -1;
		break;
	case SERVER_CERTIFICATE:
		if (tls_process_certificate(conn, ct, buf, len))
			return -1;
		break;
	case SERVER_KEY_EXCHANGE:
		if (tls_process_server_key_exchange(conn, ct, buf, len))
			return -1;
		break;
	case SERVER_CERTIFICATE_REQUEST:
		if (tls_process_certificate_request(conn, ct, buf, len))
			return -1;
		break;
	case SERVER_HELLO_DONE:
		if (tls_process_server_hello_done(conn, ct, buf, len))
			return -1;
		break;
	case SERVER_CHANGE_CIPHER_SPEC:
		if (tls_process_server_change_cipher_spec(conn, ct, buf, len))
			return -1;
		break;
	case SERVER_FINISHED:
		if (tls_process_server_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, buf, *len);

	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.
 * 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)
{
	const u8 *pos, *end;
	u8 *msg = NULL, *in_msg, *in_pos, *in_end, alert, ct;
	size_t in_msg_len;

	if (conn->state == CLIENT_HELLO) {
		if (in_len)
			return NULL;
		return tls_send_client_hello(conn, out_len);
	}

	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;
		if (tlsv1_record_receive(&conn->rl, pos, end - pos,
					 in_msg, &in_msg_len, &alert)) {
			wpa_printf(MSG_DEBUG, "TLSv1: Processing received "
				   "record failed");
			tls_alert(conn, TLS_ALERT_LEVEL_FATAL, alert);
			goto failed;
		}
		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) < 0)
				goto failed;
			in_pos += in_msg_len;
		}

		pos += TLS_RECORD_HEADER_LEN + WPA_GET_BE16(pos + 3);
	}

	os_free(in_msg);
	in_msg = NULL;

	switch (conn->state) {
	case CLIENT_KEY_EXCHANGE:
		msg = tls_send_client_key_exchange(conn, out_len);
		break;
	case CHANGE_CIPHER_SPEC:
		msg = tls_send_change_cipher_spec(conn, out_len);
		break;
	case ACK_FINISHED:
		wpa_printf(MSG_DEBUG, "TLSv1: Handshake completed "
			   "successfully");
		conn->state = ESTABLISHED;
		/* Need to return something to get final TLS ACK. */
		msg = os_malloc(1);
		*out_len = 0;
		break;
	default:
		wpa_printf(MSG_DEBUG, "TLSv1: Unexpected state %d while "
			   "generating reply", conn->state);
		break;
	}

failed:
	os_free(in_msg);
	if (conn->alert_level) {
		conn->state = FAILED;
		os_free(msg);
		msg = tls_send_alert(conn, conn->alert_level,
				     conn->alert_description, out_len);
	}

	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);

	os_memcpy(out_data + TLS_RECORD_HEADER_LEN, in_data, in_len);

	if (tlsv1_record_send(&conn->rl, TLS_CONTENT_TYPE_APPLICATION_DATA,
			      out_data, out_len, 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
 * @out_data: Pointer to output buffer (decrypted data from TLS tunnel)
 * @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
 * receive data from the encrypted tunnel.
 */
int tlsv1_client_decrypt(struct tlsv1_client *conn,
			 const u8 *in_data, size_t in_len,
			 u8 *out_data, size_t out_len)
{
	const u8 *in_end, *pos;
	int res;
	u8 alert, *out_end, *out_pos;
	size_t olen;

	pos = in_data;
	in_end = in_data + in_len;
	out_pos = out_data;
	out_end = out_data + out_len;

	while (pos < in_end) {
		if (pos[0] != TLS_CONTENT_TYPE_APPLICATION_DATA) {
			wpa_printf(MSG_DEBUG, "TLSv1: Unexpected content type "
				   "0x%x", pos[0]);
			tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
				  TLS_ALERT_UNEXPECTED_MESSAGE);
			return -1;
		}

		olen = out_end - out_pos;
		res = tlsv1_record_receive(&conn->rl, pos, in_end - pos,
					   out_pos, &olen, &alert);
		if (res < 0) {
			wpa_printf(MSG_DEBUG, "TLSv1: Record layer processing "
				   "failed");
			tls_alert(conn, TLS_ALERT_LEVEL_FATAL, alert);
			return -1;
		}
		out_pos += olen;
		if (out_pos > out_end) {
			wpa_printf(MSG_DEBUG, "TLSv1: Buffer not large enough "
				   "for processing the received record");
			tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
				  TLS_ALERT_INTERNAL_ERROR);
			return -1;