diff options
Diffstat (limited to 'FreeRTOS-Plus/Source/Application-Protocols/network_transport/using_mbedtls/using_mbedtls.c')
| -rw-r--r-- | FreeRTOS-Plus/Source/Application-Protocols/network_transport/using_mbedtls/using_mbedtls.c | 851 |
1 files changed, 851 insertions, 0 deletions
diff --git a/FreeRTOS-Plus/Source/Application-Protocols/network_transport/using_mbedtls/using_mbedtls.c b/FreeRTOS-Plus/Source/Application-Protocols/network_transport/using_mbedtls/using_mbedtls.c new file mode 100644 index 000000000..cd7270be9 --- /dev/null +++ b/FreeRTOS-Plus/Source/Application-Protocols/network_transport/using_mbedtls/using_mbedtls.c @@ -0,0 +1,851 @@ +/* + * FreeRTOS V202111.00 + * Copyright (C) 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a copy of + * this software and associated documentation files (the "Software"), to deal in + * the Software without restriction, including without limitation the rights to + * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of + * the Software, and to permit persons to whom the Software is furnished to do so, + * subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in all + * copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS + * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR + * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER + * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + * + * https://www.FreeRTOS.org + * https://github.com/FreeRTOS + * + */ + +/** + * @file tls_freertos.c + * @brief TLS transport interface implementations. This implementation uses + * mbedTLS. + */ + +/* Standard includes. */ +#include <string.h> + +/* FreeRTOS includes. */ +#include "FreeRTOS.h" + +/* FreeRTOS+TCP includes. */ +#include "FreeRTOS_IP.h" +#include "FreeRTOS_Sockets.h" + +/* TLS transport header. */ +#include "using_mbedtls.h" + +/* FreeRTOS Socket wrapper include. */ +#include "sockets_wrapper.h" + +/*-----------------------------------------------------------*/ + +/** + * @brief Each compilation unit that consumes the NetworkContext must define it. + * It should contain a single pointer as seen below whenever the header file + * of this transport implementation is included to your project. + * + * @note When using multiple transports in the same compilation unit, + * define this pointer as void *. + */ +struct NetworkContext +{ + TlsTransportParams_t * pParams; +}; + +/*-----------------------------------------------------------*/ + +/** + * @brief Represents string to be logged when mbedTLS returned error + * does not contain a high-level code. + */ +static const char * pNoHighLevelMbedTlsCodeStr = "<No-High-Level-Code>"; + +/** + * @brief Represents string to be logged when mbedTLS returned error + * does not contain a low-level code. + */ +static const char * pNoLowLevelMbedTlsCodeStr = "<No-Low-Level-Code>"; + +/** + * @brief Utility for converting the high-level code in an mbedTLS error to string, + * if the code-contains a high-level code; otherwise, using a default string. + */ +#define mbedtlsHighLevelCodeOrDefault( mbedTlsCode ) \ + ( mbedtls_high_level_strerr( mbedTlsCode ) != NULL ) ? \ + mbedtls_high_level_strerr( mbedTlsCode ) : pNoHighLevelMbedTlsCodeStr + +/** + * @brief Utility for converting the level-level code in an mbedTLS error to string, + * if the code-contains a level-level code; otherwise, using a default string. + */ +#define mbedtlsLowLevelCodeOrDefault( mbedTlsCode ) \ + ( mbedtls_low_level_strerr( mbedTlsCode ) != NULL ) ? \ + mbedtls_low_level_strerr( mbedTlsCode ) : pNoLowLevelMbedTlsCodeStr + +/*-----------------------------------------------------------*/ + +/** + * @brief Initialize the mbed TLS structures in a network connection. + * + * @param[in] pSslContext The SSL context to initialize. + */ +static void sslContextInit( SSLContext_t * pSslContext ); + +/** + * @brief Free the mbed TLS structures in a network connection. + * + * @param[in] pSslContext The SSL context to free. + */ +static void sslContextFree( SSLContext_t * pSslContext ); + +/** + * @brief Add X509 certificate to the trusted list of root certificates. + * + * OpenSSL does not provide a single function for reading and loading certificates + * from files into stores, so the file API must be called. Start with the + * root certificate. + * + * @param[out] pSslContext SSL context to which the trusted server root CA is to be added. + * @param[in] pRootCa PEM-encoded string of the trusted server root CA. + * @param[in] rootCaSize Size of the trusted server root CA. + * + * @return 0 on success; otherwise, failure; + */ +static int32_t setRootCa( SSLContext_t * pSslContext, + const uint8_t * pRootCa, + size_t rootCaSize ); + +/** + * @brief Set X509 certificate as client certificate for the server to authenticate. + * + * @param[out] pSslContext SSL context to which the client certificate is to be set. + * @param[in] pClientCert PEM-encoded string of the client certificate. + * @param[in] clientCertSize Size of the client certificate. + * + * @return 0 on success; otherwise, failure; + */ +static int32_t setClientCertificate( SSLContext_t * pSslContext, + const uint8_t * pClientCert, + size_t clientCertSize ); + +/** + * @brief Set private key for the client's certificate. + * + * @param[out] pSslContext SSL context to which the private key is to be set. + * @param[in] pPrivateKey PEM-encoded string of the client private key. + * @param[in] privateKeySize Size of the client private key. + * + * @return 0 on success; otherwise, failure; + */ +static int32_t setPrivateKey( SSLContext_t * pSslContext, + const uint8_t * pPrivateKey, + size_t privateKeySize ); + +/** + * @brief Passes TLS credentials to the OpenSSL library. + * + * Provides the root CA certificate, client certificate, and private key to the + * OpenSSL library. If the client certificate or private key is not NULL, mutual + * authentication is used when performing the TLS handshake. + * + * @param[out] pSslContext SSL context to which the credentials are to be imported. + * @param[in] pNetworkCredentials TLS credentials to be imported. + * + * @return 0 on success; otherwise, failure; + */ +static int32_t setCredentials( SSLContext_t * pSslContext, + const NetworkCredentials_t * pNetworkCredentials ); + +/** + * @brief Set optional configurations for the TLS connection. + * + * This function is used to set SNI and ALPN protocols. + * + * @param[in] pSslContext SSL context to which the optional configurations are to be set. + * @param[in] pHostName Remote host name, used for server name indication. + * @param[in] pNetworkCredentials TLS setup parameters. + */ +static void setOptionalConfigurations( SSLContext_t * pSslContext, + const char * pHostName, + const NetworkCredentials_t * pNetworkCredentials ); + +/** + * @brief Setup TLS by initializing contexts and setting configurations. + * + * @param[in] pNetworkContext Network context. + * @param[in] pHostName Remote host name, used for server name indication. + * @param[in] pNetworkCredentials TLS setup parameters. + * + * @return #TLS_TRANSPORT_SUCCESS, #TLS_TRANSPORT_INSUFFICIENT_MEMORY, #TLS_TRANSPORT_INVALID_CREDENTIALS, + * or #TLS_TRANSPORT_INTERNAL_ERROR. + */ +static TlsTransportStatus_t tlsSetup( NetworkContext_t * pNetworkContext, + const char * pHostName, + const NetworkCredentials_t * pNetworkCredentials ); + +/** + * @brief Perform the TLS handshake on a TCP connection. + * + * @param[in] pNetworkContext Network context. + * @param[in] pNetworkCredentials TLS setup parameters. + * + * @return #TLS_TRANSPORT_SUCCESS, #TLS_TRANSPORT_HANDSHAKE_FAILED, or #TLS_TRANSPORT_INTERNAL_ERROR. + */ +static TlsTransportStatus_t tlsHandshake( NetworkContext_t * pNetworkContext, + const NetworkCredentials_t * pNetworkCredentials ); + +/** + * @brief Initialize mbedTLS. + * + * @param[out] entropyContext mbed TLS entropy context for generation of random numbers. + * @param[out] ctrDrgbContext mbed TLS CTR DRBG context for generation of random numbers. + * + * @return #TLS_TRANSPORT_SUCCESS, or #TLS_TRANSPORT_INTERNAL_ERROR. + */ +static TlsTransportStatus_t initMbedtls( mbedtls_entropy_context * pEntropyContext, + mbedtls_ctr_drbg_context * pCtrDrgbContext ); + +/*-----------------------------------------------------------*/ + +static void sslContextInit( SSLContext_t * pSslContext ) +{ + configASSERT( pSslContext != NULL ); + + mbedtls_ssl_config_init( &( pSslContext->config ) ); + mbedtls_x509_crt_init( &( pSslContext->rootCa ) ); + mbedtls_pk_init( &( pSslContext->privKey ) ); + mbedtls_x509_crt_init( &( pSslContext->clientCert ) ); + mbedtls_ssl_init( &( pSslContext->context ) ); +} +/*-----------------------------------------------------------*/ + +static void sslContextFree( SSLContext_t * pSslContext ) +{ + configASSERT( pSslContext != NULL ); + + mbedtls_ssl_free( &( pSslContext->context ) ); + mbedtls_x509_crt_free( &( pSslContext->rootCa ) ); + mbedtls_x509_crt_free( &( pSslContext->clientCert ) ); + mbedtls_pk_free( &( pSslContext->privKey ) ); + mbedtls_entropy_free( &( pSslContext->entropyContext ) ); + mbedtls_ctr_drbg_free( &( pSslContext->ctrDrgbContext ) ); + mbedtls_ssl_config_free( &( pSslContext->config ) ); +} +/*-----------------------------------------------------------*/ + +static int32_t setRootCa( SSLContext_t * pSslContext, + const uint8_t * pRootCa, + size_t rootCaSize ) +{ + int32_t mbedtlsError = -1; + + configASSERT( pSslContext != NULL ); + configASSERT( pRootCa != NULL ); + + /* Parse the server root CA certificate into the SSL context. */ + mbedtlsError = mbedtls_x509_crt_parse( &( pSslContext->rootCa ), + pRootCa, + rootCaSize ); + + if( mbedtlsError != 0 ) + { + LogError( ( "Failed to parse server root CA certificate: mbedTLSError= %s : %s.", + mbedtlsHighLevelCodeOrDefault( mbedtlsError ), + mbedtlsLowLevelCodeOrDefault( mbedtlsError ) ) ); + } + else + { + mbedtls_ssl_conf_ca_chain( &( pSslContext->config ), + &( pSslContext->rootCa ), + NULL ); + } + + return mbedtlsError; +} +/*-----------------------------------------------------------*/ + +static int32_t setClientCertificate( SSLContext_t * pSslContext, + const uint8_t * pClientCert, + size_t clientCertSize ) +{ + int32_t mbedtlsError = -1; + + configASSERT( pSslContext != NULL ); + configASSERT( pClientCert != NULL ); + + /* Setup the client certificate. */ + mbedtlsError = mbedtls_x509_crt_parse( &( pSslContext->clientCert ), + pClientCert, + clientCertSize ); + + if( mbedtlsError != 0 ) + { + LogError( ( "Failed to parse the client certificate: mbedTLSError= %s : %s.", + mbedtlsHighLevelCodeOrDefault( mbedtlsError ), + mbedtlsLowLevelCodeOrDefault( mbedtlsError ) ) ); + } + + return mbedtlsError; +} +/*-----------------------------------------------------------*/ + +static int32_t setPrivateKey( SSLContext_t * pSslContext, + const uint8_t * pPrivateKey, + size_t privateKeySize ) +{ + int32_t mbedtlsError = -1; + + configASSERT( pSslContext != NULL ); + configASSERT( pPrivateKey != NULL ); + + /* Setup the client private key. */ + mbedtlsError = mbedtls_pk_parse_key( &( pSslContext->privKey ), + pPrivateKey, + privateKeySize, + NULL, + 0 ); + + if( mbedtlsError != 0 ) + { + LogError( ( "Failed to parse the client key: mbedTLSError= %s : %s.", + mbedtlsHighLevelCodeOrDefault( mbedtlsError ), + mbedtlsLowLevelCodeOrDefault( mbedtlsError ) ) ); + } + + return mbedtlsError; +} +/*-----------------------------------------------------------*/ + +static int32_t setCredentials( SSLContext_t * pSslContext, + const NetworkCredentials_t * pNetworkCredentials ) +{ + int32_t mbedtlsError = -1; + + configASSERT( pSslContext != NULL ); + configASSERT( pNetworkCredentials != NULL ); + + /* Set up the certificate security profile, starting from the default value. */ + pSslContext->certProfile = mbedtls_x509_crt_profile_default; + + /* Set SSL authmode and the RNG context. */ + mbedtls_ssl_conf_authmode( &( pSslContext->config ), + MBEDTLS_SSL_VERIFY_REQUIRED ); + mbedtls_ssl_conf_rng( &( pSslContext->config ), + mbedtls_ctr_drbg_random, + &( pSslContext->ctrDrgbContext ) ); + mbedtls_ssl_conf_cert_profile( &( pSslContext->config ), + &( pSslContext->certProfile ) ); + + mbedtlsError = setRootCa( pSslContext, + pNetworkCredentials->pRootCa, + pNetworkCredentials->rootCaSize ); + + if( ( pNetworkCredentials->pClientCert != NULL ) && + ( pNetworkCredentials->pPrivateKey != NULL ) ) + { + if( mbedtlsError == 0 ) + { + mbedtlsError = setClientCertificate( pSslContext, + pNetworkCredentials->pClientCert, + pNetworkCredentials->clientCertSize ); + } + + if( mbedtlsError == 0 ) + { + mbedtlsError = setPrivateKey( pSslContext, + pNetworkCredentials->pPrivateKey, + pNetworkCredentials->privateKeySize ); + } + + if( mbedtlsError == 0 ) + { + mbedtlsError = mbedtls_ssl_conf_own_cert( &( pSslContext->config ), + &( pSslContext->clientCert ), + &( pSslContext->privKey ) ); + } + } + + return mbedtlsError; +} +/*-----------------------------------------------------------*/ + +static void setOptionalConfigurations( SSLContext_t * pSslContext, + const char * pHostName, + const NetworkCredentials_t * pNetworkCredentials ) +{ + int32_t mbedtlsError = -1; + + configASSERT( pSslContext != NULL ); + configASSERT( pHostName != NULL ); + configASSERT( pNetworkCredentials != NULL ); + + if( pNetworkCredentials->pAlpnProtos != NULL ) + { + /* Include an application protocol list in the TLS ClientHello + * message. */ + mbedtlsError = mbedtls_ssl_conf_alpn_protocols( &( pSslContext->config ), + pNetworkCredentials->pAlpnProtos ); + + if( mbedtlsError != 0 ) + { + LogError( ( "Failed to configure ALPN protocol in mbed TLS: mbedTLSError= %s : %s.", + mbedtlsHighLevelCodeOrDefault( mbedtlsError ), + mbedtlsLowLevelCodeOrDefault( mbedtlsError ) ) ); + } + } + + /* Enable SNI if requested. */ + if( pNetworkCredentials->disableSni == pdFALSE ) + { + mbedtlsError = mbedtls_ssl_set_hostname( &( pSslContext->context ), + pHostName ); + + if( mbedtlsError != 0 ) + { + LogError( ( "Failed to set server name: mbedTLSError= %s : %s.", + mbedtlsHighLevelCodeOrDefault( mbedtlsError ), + mbedtlsLowLevelCodeOrDefault( mbedtlsError ) ) ); + } + } + + /* Set Maximum Fragment Length if enabled. */ + #ifdef MBEDTLS_SSL_MAX_FRAGMENT_LENGTH + + /* Enable the max fragment extension. 4096 bytes is currently the largest fragment size permitted. + * See RFC 8449 https://tools.ietf.org/html/rfc8449 for more information. + * + * Smaller values can be found in "mbedtls/include/ssl.h". + */ + mbedtlsError = mbedtls_ssl_conf_max_frag_len( &( pSslContext->config ), MBEDTLS_SSL_MAX_FRAG_LEN_4096 ); + + if( mbedtlsError != 0 ) + { + LogError( ( "Failed to maximum fragment length extension: mbedTLSError= %s : %s.", + mbedtlsHighLevelCodeOrDefault( mbedtlsError ), + mbedtlsLowLevelCodeOrDefault( mbedtlsError ) ) ); + } + #endif /* ifdef MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */ +} +/*-----------------------------------------------------------*/ + +static TlsTransportStatus_t tlsSetup( NetworkContext_t * pNetworkContext, + const char * pHostName, + const NetworkCredentials_t * pNetworkCredentials ) +{ + TlsTransportParams_t * pTlsTransportParams = NULL; + TlsTransportStatus_t returnStatus = TLS_TRANSPORT_SUCCESS; + int32_t mbedtlsError = 0; + + configASSERT( pNetworkContext != NULL ); + configASSERT( pNetworkContext->pParams != NULL ); + configASSERT( pHostName != NULL ); + configASSERT( pNetworkCredentials != NULL ); + configASSERT( pNetworkCredentials->pRootCa != NULL ); + + pTlsTransportParams = pNetworkContext->pParams; + /* Initialize the mbed TLS context structures. */ + sslContextInit( &( pTlsTransportParams->sslContext ) ); + + mbedtlsError = mbedtls_ssl_config_defaults( &( pTlsTransportParams->sslContext.config ), + MBEDTLS_SSL_IS_CLIENT, + MBEDTLS_SSL_TRANSPORT_STREAM, + MBEDTLS_SSL_PRESET_DEFAULT ); + + if( mbedtlsError != 0 ) + { + LogError( ( "Failed to set default SSL configuration: mbedTLSError= %s : %s.", + mbedtlsHighLevelCodeOrDefault( mbedtlsError ), + mbedtlsLowLevelCodeOrDefault( mbedtlsError ) ) ); + + /* Per mbed TLS docs, mbedtls_ssl_config_defaults only fails on memory allocation. */ + returnStatus = TLS_TRANSPORT_INSUFFICIENT_MEMORY; + } + + if( returnStatus == TLS_TRANSPORT_SUCCESS ) + { + mbedtlsError = setCredentials( &( pTlsTransportParams->sslContext ), + pNetworkCredentials ); + + if( mbedtlsError != 0 ) + { + returnStatus = TLS_TRANSPORT_INVALID_CREDENTIALS; + } + else + { + /* Optionally set SNI and ALPN protocols. */ + setOptionalConfigurations( &( pTlsTransportParams->sslContext ), + pHostName, + pNetworkCredentials ); + } + } + + return returnStatus; +} +/*-----------------------------------------------------------*/ + +static TlsTransportStatus_t tlsHandshake( NetworkContext_t * pNetworkContext, + const NetworkCredentials_t * pNetworkCredentials ) +{ + TlsTransportParams_t * pTlsTransportParams = NULL; + TlsTransportStatus_t returnStatus = TLS_TRANSPORT_SUCCESS; + int32_t mbedtlsError = 0; + + configASSERT( pNetworkContext != NULL ); + configASSERT( pNetworkContext->pParams != NULL ); + configASSERT( pNetworkCredentials != NULL ); + + pTlsTransportParams = pNetworkContext->pParams; + /* Initialize the mbed TLS secured connection context. */ + mbedtlsError = mbedtls_ssl_setup( &( pTlsTransportParams->sslContext.context ), + &( pTlsTransportParams->sslContext.config ) ); + + if( mbedtlsError != 0 ) + { + LogError( ( "Failed to set up mbed TLS SSL context: mbedTLSError= %s : %s.", + mbedtlsHighLevelCodeOrDefault( mbedtlsError ), + mbedtlsLowLevelCodeOrDefault( mbedtlsError ) ) ); + + returnStatus = TLS_TRANSPORT_INTERNAL_ERROR; + } + else + { + /* Set the underlying IO for the TLS connection. */ + + /* MISRA Rule 11.2 flags the following line for casting the second + * parameter to void *. This rule is suppressed because + * #mbedtls_ssl_set_bio requires the second parameter as void *. + */ + /* coverity[misra_c_2012_rule_11_2_violation] */ + + /* These two macros MBEDTLS_SSL_SEND and MBEDTLS_SSL_RECV need to be + * defined in mbedtls_config.h according to which implementation you use. + */ + mbedtls_ssl_set_bio( &( pTlsTransportParams->sslContext.context ), + ( void * ) pTlsTransportParams->tcpSocket, + MBEDTLS_SSL_SEND, + MBEDTLS_SSL_RECV, + NULL ); + } + + if( returnStatus == TLS_TRANSPORT_SUCCESS ) + { + /* Perform the TLS handshake. */ + do + { + mbedtlsError = mbedtls_ssl_handshake( &( pTlsTransportParams->sslContext.context ) ); + } while( ( mbedtlsError == MBEDTLS_ERR_SSL_WANT_READ ) || + ( mbedtlsError == MBEDTLS_ERR_SSL_WANT_WRITE ) ); + + if( mbedtlsError != 0 ) + { + LogError( ( "Failed to perform TLS handshake: mbedTLSError= %s : %s.", + mbedtlsHighLevelCodeOrDefault( mbedtlsError ), + mbedtlsLowLevelCodeOrDefault( mbedtlsError ) ) ); + + returnStatus = TLS_TRANSPORT_HANDSHAKE_FAILED; + } + else + { + LogInfo( ( "(Network connection %p) TLS handshake successful.", + pNetworkContext ) ); + } + } + + return returnStatus; +} +/*-----------------------------------------------------------*/ + +static TlsTransportStatus_t initMbedtls( mbedtls_entropy_context * pEntropyContext, + mbedtls_ctr_drbg_context * pCtrDrgbContext ) +{ + TlsTransportStatus_t returnStatus = TLS_TRANSPORT_SUCCESS; + int32_t mbedtlsError = 0; + + /* Set the mutex functions for mbed TLS thread safety. */ + mbedtls_threading_set_alt( mbedtls_platform_mutex_init, + mbedtls_platform_mutex_free, + mbedtls_platform_mutex_lock, + mbedtls_platform_mutex_unlock ); + + /* Initialize contexts for random number generation. */ + mbedtls_entropy_init( pEntropyContext ); + mbedtls_ctr_drbg_init( pCtrDrgbContext ); + + /* Add a strong entropy source. At least one is required. */ + mbedtlsError = mbedtls_entropy_add_source( pEntropyContext, + mbedtls_platform_entropy_poll, + NULL, + 32, + MBEDTLS_ENTROPY_SOURCE_STRONG ); + + if( mbedtlsError != 0 ) + { + LogError( ( "Failed to add entropy source: mbedTLSError= %s : %s.", + mbedtlsHighLevelCodeOrDefault( mbedtlsError ), + mbedtlsLowLevelCodeOrDefault( mbedtlsError ) ) ); + returnStatus = TLS_TRANSPORT_INTERNAL_ERROR; + } + + if( returnStatus == TLS_TRANSPORT_SUCCESS ) + { + /* Seed the random number generator. */ + mbedtlsError = mbedtls_ctr_drbg_seed( pCtrDrgbContext, + mbedtls_entropy_func, + pEntropyContext, + NULL, + 0 ); + + if( mbedtlsError != 0 ) + { + LogError( ( "Failed to seed PRNG: mbedTLSError= %s : %s.", + mbedtlsHighLevelCodeOrDefault( mbedtlsError ), + mbedtlsLowLevelCodeOrDefault( mbedtlsError ) ) ); + returnStatus = TLS_TRANSPORT_INTERNAL_ERROR; + } + } + + if( returnStatus == TLS_TRANSPORT_SUCCESS ) + { + LogDebug( ( "Successfully initialized mbedTLS." ) ); + } + + return returnStatus; +} +/*-----------------------------------------------------------*/ + +TlsTransportStatus_t TLS_FreeRTOS_Connect( NetworkContext_t * pNetworkContext, + const char * pHostName, + uint16_t port, + const NetworkCredentials_t * pNetworkCredentials, + uint32_t receiveTimeoutMs, + uint32_t sendTimeoutMs ) +{ + TlsTransportParams_t * pTlsTransportParams = NULL; + TlsTransportStatus_t returnStatus = TLS_TRANSPORT_SUCCESS; + BaseType_t socketStatus = 0; + + if( ( pNetworkContext == NULL ) || + ( pNetworkContext->pParams == NULL ) || + ( pHostName == NULL ) || + ( pNetworkCredentials == NULL ) ) + { + LogError( ( "Invalid input parameter(s): Arguments cannot be NULL. pNetworkContext=%p, " + "pHostName=%p, pNetworkCredentials=%p.", + pNetworkContext, + pHostName, + pNetworkCredentials ) ); + returnStatus = TLS_TRANSPORT_INVALID_PARAMETER; + } + else if( ( pNetworkCredentials->pRootCa == NULL ) ) + { + LogError( ( "pRootCa cannot be NULL." ) ); + returnStatus = TLS_TRANSPORT_INVALID_PARAMETER; + } + else + { + /* Empty else for MISRA 15.7 compliance. */ + } + + /* Establish a TCP connection with the server. */ + if( returnStatus == TLS_TRANSPORT_SUCCESS ) + { + pTlsTransportParams = pNetworkContext->pParams; + socketStatus = Sockets_Connect( &( pTlsTransportParams->tcpSocket ), + pHostName, + port, + receiveTimeoutMs, + sendTimeoutMs ); + + if( socketStatus != 0 ) + { + LogError( ( "Failed to connect to %s with error %d.", + pHostName, + socketStatus ) ); + returnStatus = TLS_TRANSPORT_CONNECT_FAILURE; + } + } + + /* Initialize mbedtls. */ + if( returnStatus == TLS_TRANSPORT_SUCCESS ) + { + returnStatus = initMbedtls( &( pTlsTransportParams->sslContext.entropyContext ), + &( pTlsTransportParams->sslContext.ctrDrgbContext ) ); + } + + /* Initialize TLS contexts and set credentials. */ + if( returnStatus == TLS_TRANSPORT_SUCCESS ) + { + returnStatus = tlsSetup( pNetworkContext, pHostName, pNetworkCredentials ); + } + + /* Perform TLS handshake. */ + if( returnStatus == TLS_TRANSPORT_SUCCESS ) + { + returnStatus = tlsHandshake( pNetworkContext, pNetworkCredentials ); + } + + /* Clean up on failure. */ + if( returnStatus != TLS_TRANSPORT_SUCCESS ) + { + if( ( pNetworkContext != NULL ) && ( pNetworkContext->pParams != NULL ) ) + { + sslContextFree( &( pTlsTransportParams->sslContext ) ); + + if( pTlsTransportParams->tcpSocket != FREERTOS_INVALID_SOCKET ) + { + ( void ) FreeRTOS_closesocket( pTlsTransportParams->tcpSocket ); + } + } + } + else + { + LogInfo( ( "(Network connection %p) Connection to %s established.", + pNetworkContext, + pHostName ) ); + } + + return returnStatus; +} +/*-----------------------------------------------------------*/ + +void TLS_FreeRTOS_Disconnect( NetworkContext_t * pNetworkContext ) +{ + TlsTransportParams_t * pTlsTransportParams = NULL; + BaseType_t tlsStatus = 0; + + if( ( pNetworkContext != NULL ) && ( pNetworkContext->pParams != NULL ) ) + { + pTlsTransportParams = pNetworkContext->pParams; + /* Attempting to terminate TLS connection. */ + tlsStatus = ( BaseType_t ) mbedtls_ssl_close_notify( &( pTlsTransportParams->sslContext.context ) ); + + /* Ignore the WANT_READ and WANT_WRITE return values. */ + if( ( tlsStatus != ( BaseType_t ) MBEDTLS_ERR_SSL_WANT_READ ) && + ( tlsStatus != ( BaseType_t ) MBEDTLS_ERR_SSL_WANT_WRITE ) ) + { + if( tlsStatus == 0 ) + { + LogInfo( ( "(Network connection %p) TLS close-notify sent.", + pNetworkContext ) ); + } + else + { + LogError( ( "(Network connection %p) Failed to send TLS close-notify: mbedTLSError= %s : %s.", + pNetworkContext, + mbedtlsHighLevelCodeOrDefault( tlsStatus ), + mbedtlsLowLevelCodeOrDefault( tlsStatus ) ) ); + } + } + else + { + /* WANT_READ and WANT_WRITE can be ignored. Logging for debugging purposes. */ + LogInfo( ( "(Network connection %p) TLS close-notify sent; ", + "received %s as the TLS status can be ignored for close-notify." + ( tlsStatus == MBEDTLS_ERR_SSL_WANT_READ ) ? "WANT_READ" : "WANT_WRITE", + pNetworkContext ) ); + } + + /* Call socket shutdown function to close connection. */ + Sockets_Disconnect( pTlsTransportParams->tcpSocket ); + + /* Free mbed TLS contexts. */ + sslContextFree( &( pTlsTransportParams->sslContext ) ); + } + + /* Clear the mutex functions for mbed TLS thread safety. */ + mbedtls_threading_free_alt(); +} +/*-----------------------------------------------------------*/ + +int32_t TLS_FreeRTOS_recv( NetworkContext_t * pNetworkContext, + void * pBuffer, + size_t bytesToRecv ) +{ + TlsTransportParams_t * pTlsTransportParams = NULL; + int32_t tlsStatus = 0; + + configASSERT( ( pNetworkContext != NULL ) && ( pNetworkContext->pParams != NULL ) ); + + pTlsTransportParams = pNetworkContext->pParams; + tlsStatus = ( int32_t ) mbedtls_ssl_read( &( pTlsTransportParams->sslContext.context ), + pBuffer, + bytesToRecv ); + + if( ( tlsStatus == MBEDTLS_ERR_SSL_TIMEOUT ) || + ( tlsStatus == MBEDTLS_ERR_SSL_WANT_READ ) || + ( tlsStatus == MBEDTLS_ERR_SSL_WANT_WRITE ) ) + { + LogDebug( ( "Failed to read data. However, a read can be retried on this error. " + "mbedTLSError= %s : %s.", + mbedtlsHighLevelCodeOrDefault( tlsStatus ), + mbedtlsLowLevelCodeOrDefault( tlsStatus ) ) ); + + /* Mark these set of errors as a timeout. The libraries may retry read + * on these errors. */ + tlsStatus = 0; + } + else if( tlsStatus < 0 ) + { + LogError( ( "Failed to read data: mbedTLSError= %s : %s.", + mbedtlsHighLevelCodeOrDefault( tlsStatus ), + mbedtlsLowLevelCodeOrDefault( tlsStatus ) ) ); + } + else + { + /* Empty else marker. */ + } + + return tlsStatus; +} +/*-----------------------------------------------------------*/ + +int32_t TLS_FreeRTOS_send( NetworkContext_t * pNetworkContext, + const void * pBuffer, + size_t bytesToSend ) +{ + TlsTransportParams_t * pTlsTransportParams = NULL; + int32_t tlsStatus = 0; + + configASSERT( ( pNetworkContext != NULL ) && ( pNetworkContext->pParams != NULL ) ); + + pTlsTransportParams = pNetworkContext->pParams; + tlsStatus = ( int32_t ) mbedtls_ssl_write( &( pTlsTransportParams->sslContext.context ), + pBuffer, + bytesToSend ); + + if( ( tlsStatus == MBEDTLS_ERR_SSL_TIMEOUT ) || + ( tlsStatus == MBEDTLS_ERR_SSL_WANT_READ ) || + ( tlsStatus == MBEDTLS_ERR_SSL_WANT_WRITE ) ) + { + LogDebug( ( "Failed to send data. However, send can be retried on this error. " + "mbedTLSError= %s : %s.", + mbedtlsHighLevelCodeOrDefault( tlsStatus ), + mbedtlsLowLevelCodeOrDefault( tlsStatus ) ) ); + + /* Mark these set of errors as a timeout. The libraries may retry send + * on these errors. */ + tlsStatus = 0; + } + else if( tlsStatus < 0 ) + { + LogError( ( "Failed to send data: mbedTLSError= %s : %s.", + mbedtlsHighLevelCodeOrDefault( tlsStatus ), + mbedtlsLowLevelCodeOrDefault( tlsStatus ) ) ); + } + else + { + /* Empty else marker. */ + } + + return tlsStatus; +} +/*-----------------------------------------------------------*/ |