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test
aws-iot/src/aws_iot_mqtt_client_connect.cpp
- Committer:
- peyo
- Date:
- 2017-04-12
- Revision:
- 1:3f75eb8d46f4
- Parent:
- 0:cd5404401c2f
File content as of revision 1:3f75eb8d46f4:
/* * Copyright 2015-2016 Amazon.com, Inc. or its affiliates. All Rights Reserved. * * Licensed under the Apache License, Version 2.0 (the "License"). * You may not use this file except in compliance with the License. * A copy of the License is located at * * http://aws.amazon.com/apache2.0 * * or in the "license" file accompanying this file. This file is distributed * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either * express or implied. See the License for the specific language governing * permissions and limitations under the License. */ // Based on Eclipse Paho. /******************************************************************************* * Copyright (c) 2014 IBM Corp. * * All rights reserved. This program and the accompanying materials * are made available under the terms of the Eclipse Public License v1.0 * and Eclipse Distribution License v1.0 which accompany this distribution. * * The Eclipse Public License is available at * http://www.eclipse.org/legal/epl-v10.html * and the Eclipse Distribution License is available at * http://www.eclipse.org/org/documents/edl-v10.php. * * Contributors: * Ian Craggs - initial API and implementation and/or initial documentation *******************************************************************************/ /** * @file aws_iot_mqtt_client_connect.c * @brief MQTT client connect API definition and related functions */ #ifdef __cplusplus extern "C" { #endif #include <aws_iot_mqtt_client.h> #include "aws_iot_mqtt_client_interface.h" #include "aws_iot_mqtt_client_common_internal.h" typedef union { uint8_t all; /**< all connect flags */ #if defined(REVERSED) struct { unsigned int username : 1; /**< 3.1 user name */ unsigned int password : 1; /**< 3.1 password */ unsigned int willRetain : 1; /**< will retain setting */ unsigned int willQoS : 2; /**< will QoS value */ unsigned int will : 1; /**< will flag */ unsigned int cleansession : 1; /**< clean session flag */ unsigned int : 1; /**< unused */ } bits; #else struct { unsigned int : 1; /**< unused */ unsigned int cleansession : 1; /**< cleansession flag */ unsigned int will : 1; /**< will flag */ unsigned int willQoS : 2; /**< will QoS value */ unsigned int willRetain : 1; /**< will retain setting */ unsigned int password : 1; /**< 3.1 password */ unsigned int username : 1; /**< 3.1 user name */ } bits; #endif } MQTT_Connect_Header_Flags; /**< connect flags byte */ typedef union { uint8_t all; /**< all connack flags */ #if defined(REVERSED) struct { unsigned int sessionpresent : 1; /**< session present flag */ unsigned int : 7; /**< unused */ } bits; #else struct { unsigned int : 7; /**< unused */ unsigned int sessionpresent : 1; /**< session present flag */ } bits; #endif } MQTT_Connack_Header_Flags; /**< connack flags byte */ typedef enum { CONNACK_CONNECTION_ACCEPTED = 0, CONNACK_UNACCEPTABLE_PROTOCOL_VERSION_ERROR = 1, CONNACK_IDENTIFIER_REJECTED_ERROR = 2, CONNACK_SERVER_UNAVAILABLE_ERROR = 3, CONNACK_BAD_USERDATA_ERROR = 4, CONNACK_NOT_AUTHORIZED_ERROR = 5 } MQTT_Connack_Return_Codes; /**< Connect request response codes from server */ /** * Determines the length of the MQTT connect packet that would be produced using the supplied connect options. * @param options the options to be used to build the connect packet * @param the length of buffer needed to contain the serialized version of the packet * @return IoT_Error_t indicating function execution status */ static uint32_t _aws_iot_get_connect_packet_length(IoT_Client_Connect_Params *pConnectParams) { uint32_t len; /* Enable when adding further MQTT versions */ /*size_t len = 0; switch(pConnectParams->MQTTVersion) { case MQTT_3_1_1: len = 10; break; }*/ FUNC_ENTRY; len = 10; // Len = 10 for MQTT_3_1_1 len = len + pConnectParams->clientIDLen + 2; if(pConnectParams->isWillMsgPresent) { len = len + pConnectParams->will.topicNameLen + 2 + pConnectParams->will.msgLen + 2; } if(NULL != pConnectParams->pUsername) { len = len + pConnectParams->usernameLen + 2; } if(NULL != pConnectParams->pPassword) { len = len + pConnectParams->passwordLen + 2; } FUNC_EXIT_RC(len); } /** * Serializes the connect options into the buffer. * @param buf the buffer into which the packet will be serialized * @param len the length in bytes of the supplied buffer * @param options the options to be used to build the connect packet * @param serialized length * @return IoT_Error_t indicating function execution status */ static IoT_Error_t _aws_iot_mqtt_serialize_connect(unsigned char *pTxBuf, size_t txBufLen, IoT_Client_Connect_Params *pConnectParams, size_t *pSerializedLen) { unsigned char *ptr; uint32_t len; IoT_Error_t rc; MQTTHeader header = {0}; MQTT_Connect_Header_Flags flags = {0}; FUNC_ENTRY; if(NULL == pTxBuf || NULL == pConnectParams || NULL == pSerializedLen || (NULL == pConnectParams->pClientID && 0 != pConnectParams->clientIDLen) || (NULL != pConnectParams->pClientID && 0 == pConnectParams->clientIDLen)) { FUNC_EXIT_RC(NULL_VALUE_ERROR); } /* Check needed here before we start writing to the Tx buffer */ switch(pConnectParams->MQTTVersion) { case MQTT_3_1_1: break; default: return MQTT_CONNACK_UNACCEPTABLE_PROTOCOL_VERSION_ERROR; } ptr = pTxBuf; len = _aws_iot_get_connect_packet_length(pConnectParams); if(aws_iot_mqtt_internal_get_final_packet_length_from_remaining_length(len) > txBufLen) { FUNC_EXIT_RC(MQTT_TX_BUFFER_TOO_SHORT_ERROR); } rc = aws_iot_mqtt_internal_init_header(&header, CONNECT, QOS0, 0, 0); if(SUCCESS != rc) { FUNC_EXIT_RC(rc); } aws_iot_mqtt_internal_write_char(&ptr, header.byte); /* write header */ ptr += aws_iot_mqtt_internal_write_len_to_buffer(ptr, len); /* write remaining length */ // Enable if adding support for more versions //if(MQTT_3_1_1 == pConnectParams->MQTTVersion) { aws_iot_mqtt_internal_write_utf8_string(&ptr, "MQTT", 4); aws_iot_mqtt_internal_write_char(&ptr, (unsigned char) pConnectParams->MQTTVersion); //} flags.all = 0; flags.bits.cleansession = (pConnectParams->isCleanSession) ? 1 : 0; flags.bits.will = (pConnectParams->isWillMsgPresent) ? 1 : 0; if(flags.bits.will) { flags.bits.willQoS = pConnectParams->will.qos; flags.bits.willRetain = (pConnectParams->will.isRetained) ? 1 : 0; } if(pConnectParams->pUsername) { flags.bits.username = 1; } if(pConnectParams->pPassword) { flags.bits.password = 1; } aws_iot_mqtt_internal_write_char(&ptr, flags.all); aws_iot_mqtt_internal_write_uint_16(&ptr, pConnectParams->keepAliveIntervalInSec); /* If the code have passed the check for incorrect values above, no client id was passed as argument */ if(NULL == pConnectParams->pClientID) { aws_iot_mqtt_internal_write_uint_16(&ptr, 0); } else { aws_iot_mqtt_internal_write_utf8_string(&ptr, pConnectParams->pClientID, pConnectParams->clientIDLen); } if(pConnectParams->isWillMsgPresent) { aws_iot_mqtt_internal_write_utf8_string(&ptr, pConnectParams->will.pTopicName, pConnectParams->will.topicNameLen); aws_iot_mqtt_internal_write_utf8_string(&ptr, pConnectParams->will.pMessage, pConnectParams->will.msgLen); } if(flags.bits.username) { aws_iot_mqtt_internal_write_utf8_string(&ptr, pConnectParams->pUsername, pConnectParams->usernameLen); } if(flags.bits.password) { aws_iot_mqtt_internal_write_utf8_string(&ptr, pConnectParams->pPassword, pConnectParams->passwordLen); } *pSerializedLen = (size_t) (ptr - pTxBuf); FUNC_EXIT_RC(SUCCESS); } /** * Deserializes the supplied (wire) buffer into connack data - return code * @param sessionPresent the session present flag returned (only for MQTT 3.1.1) * @param connack_rc returned integer value of the connack return code * @param buf the raw buffer data, of the correct length determined by the remaining length field * @param buflen the length in bytes of the data in the supplied buffer * @return IoT_Error_t indicating function execution status */ static IoT_Error_t _aws_iot_mqtt_deserialize_connack(unsigned char *pSessionPresent, IoT_Error_t *pConnackRc, unsigned char *pRxBuf, size_t rxBufLen) { unsigned char *curdata, *enddata; unsigned char connack_rc_char; uint32_t decodedLen, readBytesLen; IoT_Error_t rc; MQTT_Connack_Header_Flags flags = {0}; MQTTHeader header = {0}; FUNC_ENTRY; if(NULL == pSessionPresent || NULL == pConnackRc || NULL == pRxBuf) { FUNC_EXIT_RC(NULL_VALUE_ERROR); } /* CONNACK header size is fixed at two bytes for fixed and 2 bytes for variable, * using that as minimum size * MQTT v3.1.1 Specification 3.2.1 */ if(4 > rxBufLen) { FUNC_EXIT_RC(MQTT_RX_BUFFER_TOO_SHORT_ERROR); } curdata = pRxBuf; enddata = NULL; decodedLen = 0; readBytesLen = 0; header.byte = aws_iot_mqtt_internal_read_char(&curdata); if(CONNACK != header.bits.type) { FUNC_EXIT_RC(FAILURE); } /* read remaining length */ rc = aws_iot_mqtt_internal_decode_remaining_length_from_buffer(curdata, &decodedLen, &readBytesLen); if(SUCCESS != rc) { FUNC_EXIT_RC(rc); } /* CONNACK remaining length should always be 2 as per MQTT 3.1.1 spec */ curdata += (readBytesLen); enddata = curdata + decodedLen; if(2 != (enddata - curdata)) { FUNC_EXIT_RC(MQTT_DECODE_REMAINING_LENGTH_ERROR); } flags.all = aws_iot_mqtt_internal_read_char(&curdata); *pSessionPresent = flags.bits.sessionpresent; connack_rc_char = aws_iot_mqtt_internal_read_char(&curdata); switch(connack_rc_char) { case CONNACK_CONNECTION_ACCEPTED: *pConnackRc = MQTT_CONNACK_CONNECTION_ACCEPTED; break; case CONNACK_UNACCEPTABLE_PROTOCOL_VERSION_ERROR: *pConnackRc = MQTT_CONNACK_UNACCEPTABLE_PROTOCOL_VERSION_ERROR; break; case CONNACK_IDENTIFIER_REJECTED_ERROR: *pConnackRc = MQTT_CONNACK_IDENTIFIER_REJECTED_ERROR; break; case CONNACK_SERVER_UNAVAILABLE_ERROR: *pConnackRc = MQTT_CONNACK_SERVER_UNAVAILABLE_ERROR; break; case CONNACK_BAD_USERDATA_ERROR: *pConnackRc = MQTT_CONNACK_BAD_USERDATA_ERROR; break; case CONNACK_NOT_AUTHORIZED_ERROR: *pConnackRc = MQTT_CONNACK_NOT_AUTHORIZED_ERROR; break; default: *pConnackRc = MQTT_CONNACK_UNKNOWN_ERROR; break; } FUNC_EXIT_RC(SUCCESS); } /** * @brief Check if client state is valid for a connect request * * Called to check if client state is valid for a connect request * @param pClient Reference to the IoT Client * * @return bool true = state is valid, false = not valid */ static bool _aws_iot_mqtt_is_client_state_valid_for_connect(ClientState clientState) { bool isValid = false; switch(clientState) { case CLIENT_STATE_INVALID: isValid = false; break; case CLIENT_STATE_INITIALIZED: isValid = true; break; case CLIENT_STATE_CONNECTING: case CLIENT_STATE_CONNECTED_IDLE: case CLIENT_STATE_CONNECTED_YIELD_IN_PROGRESS: case CLIENT_STATE_CONNECTED_PUBLISH_IN_PROGRESS: case CLIENT_STATE_CONNECTED_SUBSCRIBE_IN_PROGRESS: case CLIENT_STATE_CONNECTED_UNSUBSCRIBE_IN_PROGRESS: case CLIENT_STATE_CONNECTED_RESUBSCRIBE_IN_PROGRESS: case CLIENT_STATE_CONNECTED_WAIT_FOR_CB_RETURN: case CLIENT_STATE_DISCONNECTING: isValid = false; break; case CLIENT_STATE_DISCONNECTED_ERROR: case CLIENT_STATE_DISCONNECTED_MANUALLY: case CLIENT_STATE_PENDING_RECONNECT: isValid = true; break; default: break; } return isValid; } /** * @brief MQTT Connection Function * * Called to establish an MQTT connection with the AWS IoT Service * This is the internal function which is called by the connect API to perform the operation. * Not meant to be called directly as it doesn't do validations or client state changes * * @param pClient Reference to the IoT Client * @param pConnectParams Pointer to MQTT connection parameters * * @return An IoT Error Type defining successful/failed connection */ static IoT_Error_t _aws_iot_mqtt_internal_connect(AWS_IoT_Client *pClient, IoT_Client_Connect_Params *pConnectParams) { TimerAWS connect_timer; IoT_Error_t connack_rc = FAILURE; char sessionPresent = 0; size_t len = 0; IoT_Error_t rc = FAILURE; FUNC_ENTRY; if(NULL != pConnectParams) { /* override default options if new options were supplied */ rc = aws_iot_mqtt_set_connect_params(pClient, pConnectParams); if(SUCCESS != rc) { FUNC_EXIT_RC(MQTT_CONNECTION_ERROR); } } rc = pClient->networkStack.connect(&(pClient->networkStack), NULL); if(SUCCESS != rc) { /* TLS Connect failed, return error */ FUNC_EXIT_RC(rc); } init_timer(&connect_timer); countdown_ms(&connect_timer, pClient->clientData.commandTimeoutMs); pClient->clientData.keepAliveInterval = pClient->clientData.options.keepAliveIntervalInSec; rc = _aws_iot_mqtt_serialize_connect(pClient->clientData.writeBuf, pClient->clientData.writeBufSize, &(pClient->clientData.options), &len); if(SUCCESS != rc || 0 >= len) { FUNC_EXIT_RC(rc); } /* send the connect packet */ rc = aws_iot_mqtt_internal_send_packet(pClient, len, &connect_timer); if(SUCCESS != rc) { FUNC_EXIT_RC(rc); } /* this will be a blocking call, wait for the CONNACK */ rc = aws_iot_mqtt_internal_wait_for_read(pClient, CONNACK, &connect_timer); if(SUCCESS != rc) { FUNC_EXIT_RC(rc); } /* Received CONNACK, check the return code */ rc = _aws_iot_mqtt_deserialize_connack((unsigned char *) &sessionPresent, &connack_rc, pClient->clientData.readBuf, pClient->clientData.readBufSize); if(SUCCESS != rc) { FUNC_EXIT_RC(rc); } if(MQTT_CONNACK_CONNECTION_ACCEPTED != connack_rc) { FUNC_EXIT_RC(connack_rc); } pClient->clientStatus.isPingOutstanding = false; countdown_sec(&pClient->pingTimer, pClient->clientData.keepAliveInterval); FUNC_EXIT_RC(SUCCESS); } /** * @brief MQTT Connection Function * * Called to establish an MQTT connection with the AWS IoT Service * This is the outer function which does the validations and calls the internal connect above * to perform the actual operation. It is also responsible for client state changes * * @param pClient Reference to the IoT Client * @param pConnectParams Pointer to MQTT connection parameters * * @return An IoT Error Type defining successful/failed connection */ IoT_Error_t aws_iot_mqtt_connect(AWS_IoT_Client *pClient, IoT_Client_Connect_Params *pConnectParams) { IoT_Error_t rc, disconRc; ClientState clientState; FUNC_ENTRY; if(NULL == pClient) { FUNC_EXIT_RC(NULL_VALUE_ERROR); } clientState = aws_iot_mqtt_get_client_state(pClient); if(false == _aws_iot_mqtt_is_client_state_valid_for_connect(clientState)) { /* Don't send connect packet again if we are already connected * or in the process of connecting/disconnecting */ FUNC_EXIT_RC(NETWORK_ALREADY_CONNECTED_ERROR); } aws_iot_mqtt_set_client_state(pClient, clientState, CLIENT_STATE_CONNECTING); rc = _aws_iot_mqtt_internal_connect(pClient, pConnectParams); if(SUCCESS != rc) { pClient->networkStack.disconnect(&(pClient->networkStack)); disconRc = pClient->networkStack.destroy(&(pClient->networkStack)); aws_iot_mqtt_set_client_state(pClient, CLIENT_STATE_CONNECTING, CLIENT_STATE_DISCONNECTED_ERROR); } else { aws_iot_mqtt_set_client_state(pClient, CLIENT_STATE_CONNECTING, CLIENT_STATE_CONNECTED_IDLE); } FUNC_EXIT_RC(rc); } /** * @brief Disconnect an MQTT Connection * * Called to send a disconnect message to the broker. * This is the internal function which is called by the disconnect API to perform the operation. * Not meant to be called directly as it doesn't do validations or client state changes * * @param pClient Reference to the IoT Client * * @return An IoT Error Type defining successful/failed send of the disconnect control packet. */ IoT_Error_t _aws_iot_mqtt_internal_disconnect(AWS_IoT_Client *pClient) { /* We might wait for incomplete incoming publishes to complete */ TimerAWS timer; size_t serialized_len = 0; IoT_Error_t rc; FUNC_ENTRY; rc = aws_iot_mqtt_internal_serialize_zero(pClient->clientData.writeBuf, pClient->clientData.writeBufSize, DISCONNECT, &serialized_len); if(SUCCESS != rc) { FUNC_EXIT_RC(rc); } init_timer(&timer); countdown_ms(&timer, pClient->clientData.commandTimeoutMs); /* send the disconnect packet */ if(serialized_len > 0) { rc = aws_iot_mqtt_internal_send_packet(pClient, serialized_len, &timer); if(SUCCESS != rc) { FUNC_EXIT_RC(rc); } } /* Clean network stack */ pClient->networkStack.disconnect(&(pClient->networkStack)); rc = pClient->networkStack.destroy(&(pClient->networkStack)); if(0 != rc) { /* TLS Destroy failed, return error */ FUNC_EXIT_RC(FAILURE); } FUNC_EXIT_RC(SUCCESS); } /** * @brief Disconnect an MQTT Connection * * Called to send a disconnect message to the broker. * This is the outer function which does the validations and calls the internal disconnect above * to perform the actual operation. It is also responsible for client state changes * * @param pClient Reference to the IoT Client * * @return An IoT Error Type defining successful/failed send of the disconnect control packet. */ IoT_Error_t aws_iot_mqtt_disconnect(AWS_IoT_Client *pClient) { ClientState clientState; IoT_Error_t rc; FUNC_ENTRY; if(NULL == pClient) { FUNC_EXIT_RC(NULL_VALUE_ERROR); } clientState = aws_iot_mqtt_get_client_state(pClient); if(!aws_iot_mqtt_is_client_connected(pClient)) { /* Network is already disconnected. Do nothing */ FUNC_EXIT_RC(NETWORK_DISCONNECTED_ERROR); } rc = aws_iot_mqtt_set_client_state(pClient, clientState, CLIENT_STATE_DISCONNECTING); if(SUCCESS != rc) { FUNC_EXIT_RC(rc); } rc = _aws_iot_mqtt_internal_disconnect(pClient); if(SUCCESS != rc) { pClient->clientStatus.clientState = clientState; } else { /* If called from Keepalive, this gets set to CLIENT_STATE_DISCONNECTED_ERROR */ pClient->clientStatus.clientState = CLIENT_STATE_DISCONNECTED_MANUALLY; } FUNC_EXIT_RC(rc); } /** * @brief MQTT Manual Re-Connection Function * * Called to establish an MQTT connection with the AWS IoT Service * using parameters from the last time a connection was attempted * Use after disconnect to start the reconnect process manually * Makes only one reconnect attempt. Sets the client state to * pending reconnect in case of failure * * @param pClient Reference to the IoT Client * * @return An IoT Error Type defining successful/failed connection */ IoT_Error_t aws_iot_mqtt_attempt_reconnect(AWS_IoT_Client *pClient) { IoT_Error_t rc; FUNC_ENTRY; if(NULL == pClient) { FUNC_EXIT_RC(NULL_VALUE_ERROR); } if(aws_iot_mqtt_is_client_connected(pClient)) { FUNC_EXIT_RC(NETWORK_ALREADY_CONNECTED_ERROR); } /* Ignoring return code. failures expected if network is disconnected */ rc = aws_iot_mqtt_connect(pClient, NULL); /* If still disconnected handle disconnect */ if(CLIENT_STATE_CONNECTED_IDLE != aws_iot_mqtt_get_client_state(pClient)) { aws_iot_mqtt_set_client_state(pClient, CLIENT_STATE_DISCONNECTED_ERROR, CLIENT_STATE_PENDING_RECONNECT); FUNC_EXIT_RC(NETWORK_ATTEMPTING_RECONNECT); } rc = aws_iot_mqtt_resubscribe(pClient); if(SUCCESS != rc) { FUNC_EXIT_RC(rc); } FUNC_EXIT_RC(NETWORK_RECONNECTED); } #ifdef __cplusplus } #endif