eap_tls_common.c

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			wpa_printf(MSG_INFO, "SSL: more data than TLS message "
				   "length indicated");
			data->tls_in_left = 0;
			return NULL;
		}
		data->tls_in_left -= in_len;
		if (data->tls_in_left > 0) {
			wpa_printf(MSG_DEBUG, "SSL: Need %lu bytes more input "
				   "data", (unsigned long) data->tls_in_left);
			*need_more_input = 1;
			return NULL;
		}
	} else {
		data->tls_in_left = 0;
		data->tls_in = os_malloc(in_len ? in_len : 1);
		if (data->tls_in == NULL)
			return NULL;
		os_memcpy(data->tls_in, in_data, in_len);
		data->tls_in_len = in_len;
	}

	*out_len = data->tls_in_len;
	return data->tls_in;
}


static int eap_tls_process_input(struct eap_sm *sm, struct eap_ssl_data *data,
				 const u8 *in_data, size_t in_len,
				 u8 **out_data, size_t *out_len)
{
	const u8 *msg;
	size_t msg_len;
	int need_more_input;
	u8 *appl_data;
	size_t appl_data_len;

	msg = eap_tls_data_reassemble(sm, data, in_data, in_len,
				      &msg_len, &need_more_input);
	if (msg == NULL)
		return need_more_input ? 1 : -1;

	/* Full TLS message reassembled - continue handshake processing */
	if (data->tls_out) {
		/* This should not happen.. */
		wpa_printf(MSG_INFO, "SSL: eap_tls_process_helper - pending "
			   "tls_out data even though tls_out_len = 0");
		os_free(data->tls_out);
		WPA_ASSERT(data->tls_out == NULL);
	}
	appl_data = NULL;
	data->tls_out = tls_connection_handshake(sm->ssl_ctx, data->conn,
						 msg, msg_len,
						 &data->tls_out_len,
						 &appl_data, &appl_data_len);

	/* Clear reassembled input data (if the buffer was needed). */
	data->tls_in_left = data->tls_in_total = data->tls_in_len = 0;
	os_free(data->tls_in);
	data->tls_in = NULL;

	if (appl_data &&
	    tls_connection_established(sm->ssl_ctx, data->conn) &&
	    !tls_connection_get_failed(sm->ssl_ctx, data->conn)) {
		wpa_hexdump_key(MSG_MSGDUMP, "SSL: Application data",
				appl_data, appl_data_len);
		*out_data = appl_data;
		*out_len = appl_data_len;
		return 2;
	}

	os_free(appl_data);

	return 0;
}


static int eap_tls_process_output(struct eap_ssl_data *data, EapType eap_type,
				  int peap_version, u8 id, int ret,
				  u8 **out_data, size_t *out_len)
{
	size_t len;
	u8 *pos, *flags;
	int more_fragments, length_included;
	
	wpa_printf(MSG_DEBUG, "SSL: %lu bytes left to be sent out (of total "
		   "%lu bytes)",
		   (unsigned long) data->tls_out_len - data->tls_out_pos,
		   (unsigned long) data->tls_out_len);

	len = data->tls_out_len - data->tls_out_pos;
	if (len > data->tls_out_limit) {
		more_fragments = 1;
		len = data->tls_out_limit;
		wpa_printf(MSG_DEBUG, "SSL: sending %lu bytes, more fragments "
			   "will follow", (unsigned long) len);
	} else
		more_fragments = 0;

	length_included = data->tls_out_pos == 0 &&
		(data->tls_out_len > data->tls_out_limit ||
		 data->include_tls_length);

	*out_data = (u8 *)
		eap_msg_alloc(EAP_VENDOR_IETF, eap_type, out_len,
			      1 + length_included * 4 + len, EAP_CODE_RESPONSE,
			      id, &pos);
	if (*out_data == NULL)
		return -1;

	flags = pos++;
	*flags = peap_version;
	if (more_fragments)
		*flags |= EAP_TLS_FLAGS_MORE_FRAGMENTS;
	if (length_included) {
		*flags |= EAP_TLS_FLAGS_LENGTH_INCLUDED;
		WPA_PUT_BE32(pos, data->tls_out_len);
		pos += 4;
	}

	os_memcpy(pos, &data->tls_out[data->tls_out_pos], len);
	data->tls_out_pos += len;

	if (!more_fragments) {
		data->tls_out_len = 0;
		data->tls_out_pos = 0;
		os_free(data->tls_out);
		data->tls_out = NULL;
	}

	return ret;
}


/**
 * eap_tls_process_helper - Process TLS handshake message
 * @sm: Pointer to EAP state machine allocated with eap_sm_init()
 * @data: Data for TLS processing
 * @eap_type: EAP type (EAP_TYPE_TLS, EAP_TYPE_PEAP, ...)
 * @peap_version: Version number for EAP-PEAP/TTLS
 * @id: EAP identifier for the response
 * @in_data: Message received from the server
 * @in_len: Length of in_data
 * @out_data: Buffer for returning a pointer to the response message
 * @out_len: Buffer for returning the length of the response message
 * Returns: 0 on success, 1 if more input data is needed, or -1 on failure
 *
 * This function can be used to process TLS handshake messages. It reassembles
 * the received fragments and uses a TLS library to process the messages. The
 * response data from the TLS library is fragmented to suitable output messages
 * that the caller can send out.
 *
 * out_data is used to return the response message if the return value of this
 * function is 0 or -1. In case of failure, the message is likely a TLS alarm
 * message. The caller is responsible for freeing the allocated buffer if
 * *out_data is not %NULL.
 */
int eap_tls_process_helper(struct eap_sm *sm, struct eap_ssl_data *data,
			   EapType eap_type, int peap_version,
			   u8 id, const u8 *in_data, size_t in_len,
			   u8 **out_data, size_t *out_len)
{
	int ret = 0;

	WPA_ASSERT(data->tls_out_len == 0 || in_len == 0);
	*out_len = 0;
	*out_data = NULL;

	if (data->tls_out_len == 0) {
		/* No more data to send out - expect to receive more data from
		 * the AS. */
		int res = eap_tls_process_input(sm, data, in_data, in_len,
						out_data, out_len);
		if (res)
			return res;
	}

	if (data->tls_out == NULL) {
		data->tls_out_len = 0;
		return -1;
	}

	if (tls_connection_get_failed(sm->ssl_ctx, data->conn)) {
		wpa_printf(MSG_DEBUG, "SSL: Failed - tls_out available to "
			   "report error");
		ret = -1;
		/* TODO: clean pin if engine used? */
	}

	if (data->tls_out_len == 0) {
		/* TLS negotiation should now be complete since all other cases
		 * needing more data should have been caught above based on
		 * the TLS Message Length field. */
		wpa_printf(MSG_DEBUG, "SSL: No data to be sent out");
		os_free(data->tls_out);
		data->tls_out = NULL;
		return 1;
	}

	return eap_tls_process_output(data, eap_type, peap_version, id, ret,
				      out_data, out_len);
}


/**
 * eap_tls_build_ack - Build a TLS ACK frames
 * @data: Data for TLS processing
 * @respDataLen: Buffer for returning the length of the response message
 * @id: EAP identifier for the response
 * @eap_type: EAP type (EAP_TYPE_TLS, EAP_TYPE_PEAP, ...)
 * @peap_version: Version number for EAP-PEAP/TTLS
 * Returns: Pointer to allocated ACK frames or %NULL on failure
 */
u8 * eap_tls_build_ack(struct eap_ssl_data *data, size_t *respDataLen, u8 id,
		       EapType eap_type, int peap_version)
{
	struct eap_hdr *resp;
	u8 *pos;

	resp = eap_msg_alloc(EAP_VENDOR_IETF, eap_type, respDataLen,
			     1, EAP_CODE_RESPONSE, id, &pos);
	if (resp == NULL)
		return NULL;
	wpa_printf(MSG_DEBUG, "SSL: Building ACK");
	*pos = peap_version; /* Flags */
	return (u8 *) resp;
}


/**
 * eap_tls_reauth_init - Re-initialize shared TLS for session resumption
 * @sm: Pointer to EAP state machine allocated with eap_sm_init()
 * @data: Data for TLS processing
 * Returns: 0 on success, -1 on failure
 */
int eap_tls_reauth_init(struct eap_sm *sm, struct eap_ssl_data *data)
{
	os_free(data->tls_in);
	data->tls_in = NULL;
	data->tls_in_len = data->tls_in_left = data->tls_in_total = 0;
	os_free(data->tls_out);
	data->tls_out = NULL;
	data->tls_out_len = data->tls_out_pos = 0;

	return tls_connection_shutdown(sm->ssl_ctx, data->conn);
}


/**
 * eap_tls_status - Get TLS status
 * @sm: Pointer to EAP state machine allocated with eap_sm_init()
 * @data: Data for TLS processing
 * @buf: Buffer for status information
 * @buflen: Maximum buffer length
 * @verbose: Whether to include verbose status information
 * Returns: Number of bytes written to buf.
 */
int eap_tls_status(struct eap_sm *sm, struct eap_ssl_data *data, char *buf,
		   size_t buflen, int verbose)
{
	char name[128];
	int len = 0, ret;

	if (tls_get_cipher(sm->ssl_ctx, data->conn, name, sizeof(name)) == 0) {
		ret = os_snprintf(buf + len, buflen - len,
				  "EAP TLS cipher=%s\n", name);
		if (ret < 0 || (size_t) ret >= buflen - len)
			return len;
		len += ret;
	}

	return len;
}


/**
 * eap_tls_process_init - Initial validation and processing of EAP requests
 * @sm: Pointer to EAP state machine allocated with eap_sm_init()
 * @data: Data for TLS processing
 * @eap_type: EAP type (EAP_TYPE_TLS, EAP_TYPE_PEAP, ...)
 * @ret: Return values from EAP request validation and processing
 * @reqData: EAP request to be processed (eapReqData)
 * @reqDataLen: Length of the EAP request
 * @len: Buffer for returning length of the remaining payload
 * @flags: Buffer for returning TLS flags
 * Returns: Buffer to payload after TLS flags and length or %NULL on failure
 */
const u8 * eap_tls_process_init(struct eap_sm *sm, struct eap_ssl_data *data,
				EapType eap_type, struct eap_method_ret *ret,
				const u8 *reqData, size_t reqDataLen,
				size_t *len, u8 *flags)
{
	const u8 *pos;
	size_t left;
	unsigned int tls_msg_len;

	if (tls_get_errors(sm->ssl_ctx)) {
		wpa_printf(MSG_INFO, "SSL: TLS errors detected");
		ret->ignore = TRUE;
		return NULL;
	}

	pos = eap_hdr_validate(EAP_VENDOR_IETF, eap_type, reqData, reqDataLen,
			       &left);
	if (pos == NULL) {
		ret->ignore = TRUE;
		return NULL;
	}
	*flags = *pos++;
	left--;
	wpa_printf(MSG_DEBUG, "SSL: Received packet(len=%lu) - "
		   "Flags 0x%02x", (unsigned long) reqDataLen, *flags);
	if (*flags & EAP_TLS_FLAGS_LENGTH_INCLUDED) {
		if (left < 4) {
			wpa_printf(MSG_INFO, "SSL: Short frame with TLS "
				   "length");
			ret->ignore = TRUE;
			return NULL;
		}
		tls_msg_len = WPA_GET_BE32(pos);
		wpa_printf(MSG_DEBUG, "SSL: TLS Message Length: %d",
			   tls_msg_len);
		if (data->tls_in_left == 0) {
			data->tls_in_total = tls_msg_len;
			data->tls_in_left = tls_msg_len;
			os_free(data->tls_in);
			data->tls_in = NULL;
			data->tls_in_len = 0;
		}
		pos += 4;
		left -= 4;
	}

	ret->ignore = FALSE;
	ret->methodState = METHOD_MAY_CONT;
	ret->decision = DECISION_FAIL;
	ret->allowNotifications = TRUE;

	*len = (size_t) left;
	return pos;
}