/** * \file ssl_misc.h * * \brief Internal functions shared by the SSL modules */ /* * Copyright The Mbed TLS Contributors * SPDX-License-Identifier: Apache-2.0 * * Licensed under the Apache License, Version 2.0 (the "License"); you may * not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License 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. */ #ifndef MBEDTLS_SSL_MISC_H #define MBEDTLS_SSL_MISC_H #include "mbedtls/build_info.h" #include "mbedtls/ssl.h" #include "mbedtls/cipher.h" #if defined(MBEDTLS_USE_PSA_CRYPTO) #include "psa/crypto.h" #endif #if defined(MBEDTLS_MD5_C) #include "mbedtls/md5.h" #endif #if defined(MBEDTLS_SHA1_C) #include "mbedtls/sha1.h" #endif #if defined(MBEDTLS_SHA256_C) #include "mbedtls/sha256.h" #endif #if defined(MBEDTLS_SHA512_C) #include "mbedtls/sha512.h" #endif #if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) #include "mbedtls/ecjpake.h" #endif #if defined(MBEDTLS_USE_PSA_CRYPTO) #include "psa/crypto.h" #include "mbedtls/psa_util.h" #endif /* MBEDTLS_USE_PSA_CRYPTO */ #if ( defined(__ARMCC_VERSION) || defined(_MSC_VER) ) && \ !defined(inline) && !defined(__cplusplus) #define inline __inline #endif /* Legacy minor version numbers as defined by: * - RFC 2246: ProtocolVersion version = { 3, 1 }; // TLS v1.0 * - RFC 4346: ProtocolVersion version = { 3, 2 }; // TLS v1.1 * * We no longer support these versions, but some code still references those * constants as part of negotiating with the peer, so keep them available * internally. */ #define MBEDTLS_SSL_MINOR_VERSION_1 1 #define MBEDTLS_SSL_MINOR_VERSION_2 2 /* Determine minimum supported version */ #define MBEDTLS_SSL_MIN_MAJOR_VERSION MBEDTLS_SSL_MAJOR_VERSION_3 #if defined(MBEDTLS_SSL_PROTO_TLS1_2) #define MBEDTLS_SSL_MIN_MINOR_VERSION MBEDTLS_SSL_MINOR_VERSION_3 #endif /* MBEDTLS_SSL_PROTO_TLS1_2 */ #define MBEDTLS_SSL_MIN_VALID_MINOR_VERSION MBEDTLS_SSL_MINOR_VERSION_3 #define MBEDTLS_SSL_MIN_VALID_MAJOR_VERSION MBEDTLS_SSL_MAJOR_VERSION_3 /* Determine maximum supported version */ #define MBEDTLS_SSL_MAX_MAJOR_VERSION MBEDTLS_SSL_MAJOR_VERSION_3 #if defined(MBEDTLS_SSL_PROTO_TLS1_2) #define MBEDTLS_SSL_MAX_MINOR_VERSION MBEDTLS_SSL_MINOR_VERSION_3 #endif /* MBEDTLS_SSL_PROTO_TLS1_2 */ /* Shorthand for restartable ECC */ #if defined(MBEDTLS_ECP_RESTARTABLE) && \ defined(MBEDTLS_SSL_CLI_C) && \ defined(MBEDTLS_SSL_PROTO_TLS1_2) && \ defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) #define MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED #endif #define MBEDTLS_SSL_INITIAL_HANDSHAKE 0 #define MBEDTLS_SSL_RENEGOTIATION_IN_PROGRESS 1 /* In progress */ #define MBEDTLS_SSL_RENEGOTIATION_DONE 2 /* Done or aborted */ #define MBEDTLS_SSL_RENEGOTIATION_PENDING 3 /* Requested (server only) */ /* * Mask of TLS 1.3 handshake extensions used in extensions_present * of mbedtls_ssl_handshake_params. */ #define MBEDTLS_SSL_EXT_NONE 0 #define MBEDTLS_SSL_EXT_SERVERNAME ( 1 << 0 ) #define MBEDTLS_SSL_EXT_MAX_FRAGMENT_LENGTH ( 1 << 1 ) #define MBEDTLS_SSL_EXT_STATUS_REQUEST ( 1 << 2 ) #define MBEDTLS_SSL_EXT_SUPPORTED_GROUPS ( 1 << 3 ) #define MBEDTLS_SSL_EXT_SIG_ALG ( 1 << 4 ) #define MBEDTLS_SSL_EXT_USE_SRTP ( 1 << 5 ) #define MBEDTLS_SSL_EXT_HEARTBEAT ( 1 << 6 ) #define MBEDTLS_SSL_EXT_ALPN ( 1 << 7 ) #define MBEDTLS_SSL_EXT_SCT ( 1 << 8 ) #define MBEDTLS_SSL_EXT_CLI_CERT_TYPE ( 1 << 9 ) #define MBEDTLS_SSL_EXT_SERV_CERT_TYPE ( 1 << 10 ) #define MBEDTLS_SSL_EXT_PADDING ( 1 << 11 ) #define MBEDTLS_SSL_EXT_PRE_SHARED_KEY ( 1 << 12 ) #define MBEDTLS_SSL_EXT_EARLY_DATA ( 1 << 13 ) #define MBEDTLS_SSL_EXT_SUPPORTED_VERSIONS ( 1 << 14 ) #define MBEDTLS_SSL_EXT_COOKIE ( 1 << 15 ) #define MBEDTLS_SSL_EXT_PSK_KEY_EXCHANGE_MODES ( 1 << 16 ) #define MBEDTLS_SSL_EXT_CERT_AUTH ( 1 << 17 ) #define MBEDTLS_SSL_EXT_OID_FILTERS ( 1 << 18 ) #define MBEDTLS_SSL_EXT_POST_HANDSHAKE_AUTH ( 1 << 19 ) #define MBEDTLS_SSL_EXT_SIG_ALG_CERT ( 1 << 20 ) #define MBEDTLS_SSL_EXT_KEY_SHARE ( 1 << 21 ) /* * Helper macros for function call with return check. */ /* * Exit when return non-zero value */ #define MBEDTLS_SSL_PROC_CHK( f ) \ do { \ ret = ( f ); \ if( ret != 0 ) \ { \ goto cleanup; \ } \ } while( 0 ) /* * Exit when return negative value */ #define MBEDTLS_SSL_PROC_CHK_NEG( f ) \ do { \ ret = ( f ); \ if( ret < 0 ) \ { \ goto cleanup; \ } \ } while( 0 ) /* * DTLS retransmission states, see RFC 6347 4.2.4 * * The SENDING state is merged in PREPARING for initial sends, * but is distinct for resends. * * Note: initial state is wrong for server, but is not used anyway. */ #define MBEDTLS_SSL_RETRANS_PREPARING 0 #define MBEDTLS_SSL_RETRANS_SENDING 1 #define MBEDTLS_SSL_RETRANS_WAITING 2 #define MBEDTLS_SSL_RETRANS_FINISHED 3 /* * Allow extra bytes for record, authentication and encryption overhead: * counter (8) + header (5) + IV(16) + MAC (16-48) + padding (0-256). */ #if defined(MBEDTLS_SSL_PROTO_TLS1_2) /* This macro determines whether CBC is supported. */ #if defined(MBEDTLS_CIPHER_MODE_CBC) && \ ( defined(MBEDTLS_AES_C) || \ defined(MBEDTLS_CAMELLIA_C) || \ defined(MBEDTLS_ARIA_C) || \ defined(MBEDTLS_DES_C) ) #define MBEDTLS_SSL_SOME_SUITES_USE_CBC #endif /* This macro determines whether a ciphersuite using a * stream cipher can be used. */ #if defined(MBEDTLS_CIPHER_NULL_CIPHER) #define MBEDTLS_SSL_SOME_SUITES_USE_STREAM #endif /* This macro determines whether the CBC construct used in TLS 1.2 is supported. */ #if defined(MBEDTLS_SSL_SOME_SUITES_USE_CBC) && \ defined(MBEDTLS_SSL_PROTO_TLS1_2) #define MBEDTLS_SSL_SOME_SUITES_USE_TLS_CBC #endif #if defined(MBEDTLS_SSL_SOME_SUITES_USE_STREAM) || \ defined(MBEDTLS_SSL_SOME_SUITES_USE_CBC) #define MBEDTLS_SSL_SOME_SUITES_USE_MAC #endif #endif /* MBEDTLS_SSL_PROTO_TLS1_2 */ #if defined(MBEDTLS_SSL_SOME_SUITES_USE_MAC) /* Ciphersuites using HMAC */ #if defined(MBEDTLS_SHA384_C) #define MBEDTLS_SSL_MAC_ADD 48 /* SHA-384 used for HMAC */ #elif defined(MBEDTLS_SHA256_C) #define MBEDTLS_SSL_MAC_ADD 32 /* SHA-256 used for HMAC */ #else #define MBEDTLS_SSL_MAC_ADD 20 /* SHA-1 used for HMAC */ #endif #else /* MBEDTLS_SSL_SOME_SUITES_USE_MAC */ /* AEAD ciphersuites: GCM and CCM use a 128 bits tag */ #define MBEDTLS_SSL_MAC_ADD 16 #endif #if defined(MBEDTLS_CIPHER_MODE_CBC) #define MBEDTLS_SSL_PADDING_ADD 256 #else #define MBEDTLS_SSL_PADDING_ADD 0 #endif #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID) #define MBEDTLS_SSL_MAX_CID_EXPANSION MBEDTLS_SSL_CID_TLS1_3_PADDING_GRANULARITY #else #define MBEDTLS_SSL_MAX_CID_EXPANSION 0 #endif #define MBEDTLS_SSL_PAYLOAD_OVERHEAD ( MBEDTLS_MAX_IV_LENGTH + \ MBEDTLS_SSL_MAC_ADD + \ MBEDTLS_SSL_PADDING_ADD + \ MBEDTLS_SSL_MAX_CID_EXPANSION \ ) #define MBEDTLS_SSL_IN_PAYLOAD_LEN ( MBEDTLS_SSL_PAYLOAD_OVERHEAD + \ ( MBEDTLS_SSL_IN_CONTENT_LEN ) ) #define MBEDTLS_SSL_OUT_PAYLOAD_LEN ( MBEDTLS_SSL_PAYLOAD_OVERHEAD + \ ( MBEDTLS_SSL_OUT_CONTENT_LEN ) ) /* The maximum number of buffered handshake messages. */ #define MBEDTLS_SSL_MAX_BUFFERED_HS 4 /* Maximum length we can advertise as our max content length for RFC 6066 max_fragment_length extension negotiation purposes (the lesser of both sizes, if they are unequal.) */ #define MBEDTLS_TLS_EXT_ADV_CONTENT_LEN ( \ (MBEDTLS_SSL_IN_CONTENT_LEN > MBEDTLS_SSL_OUT_CONTENT_LEN) \ ? ( MBEDTLS_SSL_OUT_CONTENT_LEN ) \ : ( MBEDTLS_SSL_IN_CONTENT_LEN ) \ ) /* Maximum size in bytes of list in sig-hash algorithm ext., RFC 5246 */ #define MBEDTLS_SSL_MAX_SIG_HASH_ALG_LIST_LEN 65534 /* Maximum size in bytes of list in supported elliptic curve ext., RFC 4492 */ #define MBEDTLS_SSL_MAX_CURVE_LIST_LEN 65535 /* * Check that we obey the standard's message size bounds */ #if MBEDTLS_SSL_IN_CONTENT_LEN > 16384 #error "Bad configuration - incoming record content too large." #endif #if MBEDTLS_SSL_OUT_CONTENT_LEN > 16384 #error "Bad configuration - outgoing record content too large." #endif #if MBEDTLS_SSL_IN_PAYLOAD_LEN > MBEDTLS_SSL_IN_CONTENT_LEN + 2048 #error "Bad configuration - incoming protected record payload too large." #endif #if MBEDTLS_SSL_OUT_PAYLOAD_LEN > MBEDTLS_SSL_OUT_CONTENT_LEN + 2048 #error "Bad configuration - outgoing protected record payload too large." #endif /* Calculate buffer sizes */ /* Note: Even though the TLS record header is only 5 bytes long, we're internally using 8 bytes to store the implicit sequence number. */ #define MBEDTLS_SSL_HEADER_LEN 13 #if !defined(MBEDTLS_SSL_DTLS_CONNECTION_ID) #define MBEDTLS_SSL_IN_BUFFER_LEN \ ( ( MBEDTLS_SSL_HEADER_LEN ) + ( MBEDTLS_SSL_IN_PAYLOAD_LEN ) ) #else #define MBEDTLS_SSL_IN_BUFFER_LEN \ ( ( MBEDTLS_SSL_HEADER_LEN ) + ( MBEDTLS_SSL_IN_PAYLOAD_LEN ) \ + ( MBEDTLS_SSL_CID_IN_LEN_MAX ) ) #endif #if !defined(MBEDTLS_SSL_DTLS_CONNECTION_ID) #define MBEDTLS_SSL_OUT_BUFFER_LEN \ ( ( MBEDTLS_SSL_HEADER_LEN ) + ( MBEDTLS_SSL_OUT_PAYLOAD_LEN ) ) #else #define MBEDTLS_SSL_OUT_BUFFER_LEN \ ( ( MBEDTLS_SSL_HEADER_LEN ) + ( MBEDTLS_SSL_OUT_PAYLOAD_LEN ) \ + ( MBEDTLS_SSL_CID_OUT_LEN_MAX ) ) #endif #define MBEDTLS_CLIENT_HELLO_RANDOM_LEN 32 #define MBEDTLS_SERVER_HELLO_RANDOM_LEN 32 #if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH) /** * \brief Return the maximum fragment length (payload, in bytes) for * the output buffer. For the client, this is the configured * value. For the server, it is the minimum of two - the * configured value and the negotiated one. * * \sa mbedtls_ssl_conf_max_frag_len() * \sa mbedtls_ssl_get_max_out_record_payload() * * \param ssl SSL context * * \return Current maximum fragment length for the output buffer. */ size_t mbedtls_ssl_get_output_max_frag_len( const mbedtls_ssl_context *ssl ); /** * \brief Return the maximum fragment length (payload, in bytes) for * the input buffer. This is the negotiated maximum fragment * length, or, if there is none, MBEDTLS_SSL_IN_CONTENT_LEN. * If it is not defined either, the value is 2^14. This function * works as its predecessor, \c mbedtls_ssl_get_max_frag_len(). * * \sa mbedtls_ssl_conf_max_frag_len() * \sa mbedtls_ssl_get_max_in_record_payload() * * \param ssl SSL context * * \return Current maximum fragment length for the output buffer. */ size_t mbedtls_ssl_get_input_max_frag_len( const mbedtls_ssl_context *ssl ); #endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */ #if defined(MBEDTLS_SSL_VARIABLE_BUFFER_LENGTH) static inline size_t mbedtls_ssl_get_output_buflen( const mbedtls_ssl_context *ctx ) { #if defined (MBEDTLS_SSL_DTLS_CONNECTION_ID) return mbedtls_ssl_get_output_max_frag_len( ctx ) + MBEDTLS_SSL_HEADER_LEN + MBEDTLS_SSL_PAYLOAD_OVERHEAD + MBEDTLS_SSL_CID_OUT_LEN_MAX; #else return mbedtls_ssl_get_output_max_frag_len( ctx ) + MBEDTLS_SSL_HEADER_LEN + MBEDTLS_SSL_PAYLOAD_OVERHEAD; #endif } static inline size_t mbedtls_ssl_get_input_buflen( const mbedtls_ssl_context *ctx ) { #if defined (MBEDTLS_SSL_DTLS_CONNECTION_ID) return mbedtls_ssl_get_input_max_frag_len( ctx ) + MBEDTLS_SSL_HEADER_LEN + MBEDTLS_SSL_PAYLOAD_OVERHEAD + MBEDTLS_SSL_CID_IN_LEN_MAX; #else return mbedtls_ssl_get_input_max_frag_len( ctx ) + MBEDTLS_SSL_HEADER_LEN + MBEDTLS_SSL_PAYLOAD_OVERHEAD; #endif } #endif /* * TLS extension flags (for extensions with outgoing ServerHello content * that need it (e.g. for RENEGOTIATION_INFO the server already knows because * of state of the renegotiation flag, so no indicator is required) */ #define MBEDTLS_TLS_EXT_SUPPORTED_POINT_FORMATS_PRESENT (1 << 0) #define MBEDTLS_TLS_EXT_ECJPAKE_KKPP_OK (1 << 1) /** * \brief This function checks if the remaining size in a buffer is * greater or equal than a needed space. * * \param cur Pointer to the current position in the buffer. * \param end Pointer to one past the end of the buffer. * \param need Needed space in bytes. * * \return Zero if the needed space is available in the buffer, non-zero * otherwise. */ static inline int mbedtls_ssl_chk_buf_ptr( const uint8_t *cur, const uint8_t *end, size_t need ) { return( ( cur > end ) || ( need > (size_t)( end - cur ) ) ); } /** * \brief This macro checks if the remaining size in a buffer is * greater or equal than a needed space. If it is not the case, * it returns an SSL_BUFFER_TOO_SMALL error. * * \param cur Pointer to the current position in the buffer. * \param end Pointer to one past the end of the buffer. * \param need Needed space in bytes. * */ #define MBEDTLS_SSL_CHK_BUF_PTR( cur, end, need ) \ do { \ if( mbedtls_ssl_chk_buf_ptr( ( cur ), ( end ), ( need ) ) != 0 ) \ { \ return( MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL ); \ } \ } while( 0 ) /** * \brief This macro checks if the remaining length in an input buffer is * greater or equal than a needed length. If it is not the case, it * returns #MBEDTLS_ERR_SSL_DECODE_ERROR error and pends a * #MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR alert message. * * This is a function-like macro. It is guaranteed to evaluate each * argument exactly once. * * \param cur Pointer to the current position in the buffer. * \param end Pointer to one past the end of the buffer. * \param need Needed length in bytes. * */ #define MBEDTLS_SSL_CHK_BUF_READ_PTR( cur, end, need ) \ do { \ if( mbedtls_ssl_chk_buf_ptr( ( cur ), ( end ), ( need ) ) != 0 ) \ { \ MBEDTLS_SSL_DEBUG_MSG( 1, \ ( "missing input data in %s", __func__ ) ); \ MBEDTLS_SSL_PEND_FATAL_ALERT( MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR, \ MBEDTLS_ERR_SSL_DECODE_ERROR ); \ return( MBEDTLS_ERR_SSL_DECODE_ERROR ); \ } \ } while( 0 ) #ifdef __cplusplus extern "C" { #endif #if defined(MBEDTLS_SSL_PROTO_TLS1_2) && \ defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED) /* * Abstraction for a grid of allowed signature-hash-algorithm pairs. */ struct mbedtls_ssl_sig_hash_set_t { /* At the moment, we only need to remember a single suitable * hash algorithm per signature algorithm. As long as that's * the case - and we don't need a general lookup function - * we can implement the sig-hash-set as a map from signatures * to hash algorithms. */ mbedtls_md_type_t rsa; mbedtls_md_type_t ecdsa; }; #endif /* MBEDTLS_SSL_PROTO_TLS1_2 && MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED */ typedef int mbedtls_ssl_tls_prf_cb( const unsigned char *secret, size_t slen, const char *label, const unsigned char *random, size_t rlen, unsigned char *dstbuf, size_t dlen ); /* cipher.h exports the maximum IV, key and block length from * all ciphers enabled in the config, regardless of whether those * ciphers are actually usable in SSL/TLS. Notably, XTS is enabled * in the default configuration and uses 64 Byte keys, but it is * not used for record protection in SSL/TLS. * * In order to prevent unnecessary inflation of key structures, * we introduce SSL-specific variants of the max-{key,block,IV} * macros here which are meant to only take those ciphers into * account which can be negotiated in SSL/TLS. * * Since the current definitions of MBEDTLS_MAX_{KEY|BLOCK|IV}_LENGTH * in cipher.h are rough overapproximations of the real maxima, here * we content ourselves with replicating those overapproximations * for the maximum block and IV length, and excluding XTS from the * computation of the maximum key length. */ #define MBEDTLS_SSL_MAX_BLOCK_LENGTH 16 #define MBEDTLS_SSL_MAX_IV_LENGTH 16 #define MBEDTLS_SSL_MAX_KEY_LENGTH 32 /** * \brief The data structure holding the cryptographic material (key and IV) * used for record protection in TLS 1.3. */ struct mbedtls_ssl_key_set { /*! The key for client->server records. */ unsigned char client_write_key[ MBEDTLS_SSL_MAX_KEY_LENGTH ]; /*! The key for server->client records. */ unsigned char server_write_key[ MBEDTLS_SSL_MAX_KEY_LENGTH ]; /*! The IV for client->server records. */ unsigned char client_write_iv[ MBEDTLS_SSL_MAX_IV_LENGTH ]; /*! The IV for server->client records. */ unsigned char server_write_iv[ MBEDTLS_SSL_MAX_IV_LENGTH ]; size_t key_len; /*!< The length of client_write_key and * server_write_key, in Bytes. */ size_t iv_len; /*!< The length of client_write_iv and * server_write_iv, in Bytes. */ }; typedef struct mbedtls_ssl_key_set mbedtls_ssl_key_set; typedef struct { unsigned char binder_key [ MBEDTLS_TLS1_3_MD_MAX_SIZE ]; unsigned char client_early_traffic_secret [ MBEDTLS_TLS1_3_MD_MAX_SIZE ]; unsigned char early_exporter_master_secret[ MBEDTLS_TLS1_3_MD_MAX_SIZE ]; } mbedtls_ssl_tls1_3_early_secrets; typedef struct { unsigned char client_handshake_traffic_secret[ MBEDTLS_TLS1_3_MD_MAX_SIZE ]; unsigned char server_handshake_traffic_secret[ MBEDTLS_TLS1_3_MD_MAX_SIZE ]; } mbedtls_ssl_tls1_3_handshake_secrets; /* * This structure contains the parameters only needed during handshake. */ struct mbedtls_ssl_handshake_params { /* * Handshake specific crypto variables */ #if defined(MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL) int tls1_3_kex_modes; /*!< key exchange modes for TLS 1.3 */ #endif /* MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL */ #if !defined(MBEDTLS_DEPRECATED_REMOVED) const uint16_t *group_list; unsigned char group_list_heap_allocated; #endif #if defined(MBEDTLS_SSL_PROTO_TLS1_2) && \ defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED) mbedtls_ssl_sig_hash_set_t hash_algs; /*!< Set of suitable sig-hash pairs */ #endif #if defined(MBEDTLS_DHM_C) mbedtls_dhm_context dhm_ctx; /*!< DHM key exchange */ #endif /* Adding guard for MBEDTLS_ECDSA_C to ensure no compile errors due * to guards also being in ssl_srv.c and ssl_cli.c. There is a gap * in functionality that access to ecdh_ctx structure is needed for * MBEDTLS_ECDSA_C which does not seem correct. */ #if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) mbedtls_ecdh_context ecdh_ctx; /*!< ECDH key exchange */ #if defined(MBEDTLS_USE_PSA_CRYPTO) psa_key_type_t ecdh_psa_type; uint16_t ecdh_bits; psa_key_id_t ecdh_psa_privkey; unsigned char ecdh_psa_peerkey[MBEDTLS_PSA_MAX_EC_PUBKEY_LENGTH]; size_t ecdh_psa_peerkey_len; #endif /* MBEDTLS_USE_PSA_CRYPTO */ #endif /* MBEDTLS_ECDH_C || MBEDTLS_ECDSA_C */ #if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) mbedtls_ecjpake_context ecjpake_ctx; /*!< EC J-PAKE key exchange */ #if defined(MBEDTLS_SSL_CLI_C) unsigned char *ecjpake_cache; /*!< Cache for ClientHello ext */ size_t ecjpake_cache_len; /*!< Length of cached data */ #endif #endif /* MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */ #if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \ defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) const mbedtls_ecp_curve_info **curves; /*!< Supported elliptic curves */ #endif #if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED) #if defined(MBEDTLS_USE_PSA_CRYPTO) psa_key_id_t psk_opaque; /*!< Opaque PSK from the callback */ #endif /* MBEDTLS_USE_PSA_CRYPTO */ unsigned char *psk; /*!< PSK from the callback */ size_t psk_len; /*!< Length of PSK from callback */ #endif /* MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED */ #if defined(MBEDTLS_X509_CRT_PARSE_C) mbedtls_ssl_key_cert *key_cert; /*!< chosen key/cert pair (server) */ #if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION) int sni_authmode; /*!< authmode from SNI callback */ mbedtls_ssl_key_cert *sni_key_cert; /*!< key/cert list from SNI */ mbedtls_x509_crt *sni_ca_chain; /*!< trusted CAs from SNI callback */ mbedtls_x509_crl *sni_ca_crl; /*!< trusted CAs CRLs from SNI */ #endif /* MBEDTLS_SSL_SERVER_NAME_INDICATION */ #endif /* MBEDTLS_X509_CRT_PARSE_C */ #if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED) int ecrs_enabled; /*!< Handshake supports EC restart? */ mbedtls_x509_crt_restart_ctx ecrs_ctx; /*!< restart context */ enum { /* this complements ssl->state with info on intra-state operations */ ssl_ecrs_none = 0, /*!< nothing going on (yet) */ ssl_ecrs_crt_verify, /*!< Certificate: crt_verify() */ ssl_ecrs_ske_start_processing, /*!< ServerKeyExchange: pk_verify() */ ssl_ecrs_cke_ecdh_calc_secret, /*!< ClientKeyExchange: ECDH step 2 */ ssl_ecrs_crt_vrfy_sign, /*!< CertificateVerify: pk_sign() */ } ecrs_state; /*!< current (or last) operation */ mbedtls_x509_crt *ecrs_peer_cert; /*!< The peer's CRT chain. */ size_t ecrs_n; /*!< place for saving a length */ #endif #if defined(MBEDTLS_X509_CRT_PARSE_C) && \ !defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE) mbedtls_pk_context peer_pubkey; /*!< The public key from the peer. */ #endif /* MBEDTLS_X509_CRT_PARSE_C && !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */ #if defined(MBEDTLS_SSL_PROTO_DTLS) unsigned int out_msg_seq; /*!< Outgoing handshake sequence number */ unsigned int in_msg_seq; /*!< Incoming handshake sequence number */ unsigned char *verify_cookie; /*!< Cli: HelloVerifyRequest cookie Srv: unused */ unsigned char verify_cookie_len; /*!< Cli: cookie length Srv: flag for sending a cookie */ uint32_t retransmit_timeout; /*!< Current value of timeout */ unsigned char retransmit_state; /*!< Retransmission state */ mbedtls_ssl_flight_item *flight; /*!< Current outgoing flight */ mbedtls_ssl_flight_item *cur_msg; /*!< Current message in flight */ unsigned char *cur_msg_p; /*!< Position in current message */ unsigned int in_flight_start_seq; /*!< Minimum message sequence in the flight being received */ mbedtls_ssl_transform *alt_transform_out; /*!< Alternative transform for resending messages */ unsigned char alt_out_ctr[MBEDTLS_SSL_SEQUENCE_NUMBER_LEN]; /*!< Alternative record epoch/counter for resending messages */ #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID) /* The state of CID configuration in this handshake. */ uint8_t cid_in_use; /*!< This indicates whether the use of the CID extension * has been negotiated. Possible values are * #MBEDTLS_SSL_CID_ENABLED and * #MBEDTLS_SSL_CID_DISABLED. */ unsigned char peer_cid[ MBEDTLS_SSL_CID_OUT_LEN_MAX ]; /*! The peer's CID */ uint8_t peer_cid_len; /*!< The length of * \c peer_cid. */ #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */ struct { size_t total_bytes_buffered; /*!< Cumulative size of heap allocated * buffers used for message buffering. */ uint8_t seen_ccs; /*!< Indicates if a CCS message has * been seen in the current flight. */ struct mbedtls_ssl_hs_buffer { unsigned is_valid : 1; unsigned is_fragmented : 1; unsigned is_complete : 1; unsigned char *data; size_t data_len; } hs[MBEDTLS_SSL_MAX_BUFFERED_HS]; struct { unsigned char *data; size_t len; unsigned epoch; } future_record; } buffering; uint16_t mtu; /*!< Handshake mtu, used to fragment outgoing messages */ #endif /* MBEDTLS_SSL_PROTO_DTLS */ #if defined(MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL) /*! TLS 1.3 transforms for 0-RTT and encrypted handshake messages. * Those pointers own the transforms they reference. */ mbedtls_ssl_transform *transform_handshake; mbedtls_ssl_transform *transform_earlydata; #endif /* MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL */ /* * Checksum contexts */ #if defined(MBEDTLS_SSL_PROTO_TLS1_2) #if defined(MBEDTLS_SHA256_C) #if defined(MBEDTLS_USE_PSA_CRYPTO) psa_hash_operation_t fin_sha256_psa; #else mbedtls_sha256_context fin_sha256; #endif #endif #if defined(MBEDTLS_SHA384_C) #if defined(MBEDTLS_USE_PSA_CRYPTO) psa_hash_operation_t fin_sha384_psa; #else mbedtls_sha512_context fin_sha512; #endif #endif #endif /* MBEDTLS_SSL_PROTO_TLS1_2 */ void (*update_checksum)(mbedtls_ssl_context *, const unsigned char *, size_t); void (*calc_verify)(const mbedtls_ssl_context *, unsigned char *, size_t *); void (*calc_finished)(mbedtls_ssl_context *, unsigned char *, int); mbedtls_ssl_tls_prf_cb *tls_prf; #if defined(MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL) uint16_t offered_group_id; /* The NamedGroup value for the group * that is being used for ephemeral * key exchange. * * On the client: Defaults to the first * entry in the client's group list, * but can be overwritten by the HRR. */ #endif /* MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL */ /* * State-local variables used during the processing * of a specific handshake state. */ union { /* Outgoing Finished message */ struct { uint8_t preparation_done; /* Buffer holding digest of the handshake up to * but excluding the outgoing finished message. */ unsigned char digest[MBEDTLS_TLS1_3_MD_MAX_SIZE]; size_t digest_len; } finished_out; /* Incoming Finished message */ struct { uint8_t preparation_done; /* Buffer holding digest of the handshake up to but * excluding the peer's incoming finished message. */ unsigned char digest[MBEDTLS_TLS1_3_MD_MAX_SIZE]; size_t digest_len; } finished_in; } state_local; /* End of state-local variables. */ mbedtls_ssl_ciphersuite_t const *ciphersuite_info; size_t pmslen; /*!< premaster length */ unsigned char randbytes[MBEDTLS_CLIENT_HELLO_RANDOM_LEN + MBEDTLS_SERVER_HELLO_RANDOM_LEN]; /*!< random bytes */ unsigned char premaster[MBEDTLS_PREMASTER_SIZE]; /*!< premaster secret */ int resume; /*!< session resume indicator*/ int max_major_ver; /*!< max. major version client*/ int max_minor_ver; /*!< max. minor version client*/ int cli_exts; /*!< client extension presence*/ #if defined(MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL) int extensions_present; /*!< extension presence; Each bitfield represents an extension and defined as \c MBEDTLS_SSL_EXT_XXX */ union { unsigned char early [MBEDTLS_TLS1_3_MD_MAX_SIZE]; unsigned char handshake[MBEDTLS_TLS1_3_MD_MAX_SIZE]; unsigned char app [MBEDTLS_TLS1_3_MD_MAX_SIZE]; } tls1_3_master_secrets; mbedtls_ssl_tls1_3_handshake_secrets tls13_hs_secrets; #endif /* MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL */ #if defined(MBEDTLS_SSL_SESSION_TICKETS) int new_session_ticket; /*!< use NewSessionTicket? */ #endif /* MBEDTLS_SSL_SESSION_TICKETS */ #if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET) int extended_ms; /*!< use Extended Master Secret? */ #endif #if defined(MBEDTLS_SSL_ASYNC_PRIVATE) unsigned int async_in_progress : 1; /*!< an asynchronous operation is in progress */ #endif /* MBEDTLS_SSL_ASYNC_PRIVATE */ #if defined(MBEDTLS_SSL_ASYNC_PRIVATE) /** Asynchronous operation context. This field is meant for use by the * asynchronous operation callbacks (mbedtls_ssl_config::f_async_sign_start, * mbedtls_ssl_config::f_async_decrypt_start, * mbedtls_ssl_config::f_async_resume, mbedtls_ssl_config::f_async_cancel). * The library does not use it internally. */ void *user_async_ctx; #endif /* MBEDTLS_SSL_ASYNC_PRIVATE */ }; typedef struct mbedtls_ssl_hs_buffer mbedtls_ssl_hs_buffer; /* * Representation of decryption/encryption transformations on records * * There are the following general types of record transformations: * - Stream transformations (TLS versions == 1.2 only) * Transformation adding a MAC and applying a stream-cipher * to the authenticated message. * - CBC block cipher transformations ([D]TLS versions == 1.2 only) * For TLS 1.2, no IV is generated at key extraction time, but every * encrypted record is explicitly prefixed by the IV with which it was * encrypted. * - AEAD transformations ([D]TLS versions == 1.2 only) * These come in two fundamentally different versions, the first one * used in TLS 1.2, excluding ChaChaPoly ciphersuites, and the second * one used for ChaChaPoly ciphersuites in TLS 1.2 as well as for TLS 1.3. * In the first transformation, the IV to be used for a record is obtained * as the concatenation of an explicit, static 4-byte IV and the 8-byte * record sequence number, and explicitly prepending this sequence number * to the encrypted record. In contrast, in the second transformation * the IV is obtained by XOR'ing a static IV obtained at key extraction * time with the 8-byte record sequence number, without prepending the * latter to the encrypted record. * * Additionally, DTLS 1.2 + CID as well as TLS 1.3 use an inner plaintext * which allows to add flexible length padding and to hide a record's true * content type. * * In addition to type and version, the following parameters are relevant: * - The symmetric cipher algorithm to be used. * - The (static) encryption/decryption keys for the cipher. * - For stream/CBC, the type of message digest to be used. * - For stream/CBC, (static) encryption/decryption keys for the digest. * - For AEAD transformations, the size (potentially 0) of an explicit, * random initialization vector placed in encrypted records. * - For some transformations (currently AEAD) an implicit IV. It is static * and (if present) is combined with the explicit IV in a transformation- * -dependent way (e.g. appending in TLS 1.2 and XOR'ing in TLS 1.3). * - For stream/CBC, a flag determining the order of encryption and MAC. * - The details of the transformation depend on the SSL/TLS version. * - The length of the authentication tag. * * The struct below refines this abstract view as follows: * - The cipher underlying the transformation is managed in * cipher contexts cipher_ctx_{enc/dec}, which must have the * same cipher type. The mode of these cipher contexts determines * the type of the transformation in the sense above: e.g., if * the type is MBEDTLS_CIPHER_AES_256_CBC resp. MBEDTLS_CIPHER_AES_192_GCM * then the transformation has type CBC resp. AEAD. * - The cipher keys are never stored explicitly but * are maintained within cipher_ctx_{enc/dec}. * - For stream/CBC transformations, the message digest contexts * used for the MAC's are stored in md_ctx_{enc/dec}. These contexts * are unused for AEAD transformations. * - For stream/CBC transformations, the MAC keys are not stored explicitly * but maintained within md_ctx_{enc/dec}. * - The mac_enc and mac_dec fields are unused for EAD transformations. * - For transformations using an implicit IV maintained within * the transformation context, its contents are stored within * iv_{enc/dec}. * - The value of ivlen indicates the length of the IV. * This is redundant in case of stream/CBC transformations * which always use 0 resp. the cipher's block length as the * IV length, but is needed for AEAD ciphers and may be * different from the underlying cipher's block length * in this case. * - The field fixed_ivlen is nonzero for AEAD transformations only * and indicates the length of the static part of the IV which is * constant throughout the communication, and which is stored in * the first fixed_ivlen bytes of the iv_{enc/dec} arrays. * - minor_ver denotes the SSL/TLS version * - For stream/CBC transformations, maclen denotes the length of the * authentication tag, while taglen is unused and 0. * - For AEAD transformations, taglen denotes the length of the * authentication tag, while maclen is unused and 0. * - For CBC transformations, encrypt_then_mac determines the * order of encryption and authentication. This field is unused * in other transformations. * */ struct mbedtls_ssl_transform { /* * Session specific crypto layer */ size_t minlen; /*!< min. ciphertext length */ size_t ivlen; /*!< IV length */ size_t fixed_ivlen; /*!< Fixed part of IV (AEAD) */ size_t maclen; /*!< MAC(CBC) len */ size_t taglen; /*!< TAG(AEAD) len */ unsigned char iv_enc[16]; /*!< IV (encryption) */ unsigned char iv_dec[16]; /*!< IV (decryption) */ #if defined(MBEDTLS_SSL_SOME_SUITES_USE_MAC) mbedtls_md_context_t md_ctx_enc; /*!< MAC (encryption) */ mbedtls_md_context_t md_ctx_dec; /*!< MAC (decryption) */ #if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC) int encrypt_then_mac; /*!< flag for EtM activation */ #endif #endif /* MBEDTLS_SSL_SOME_SUITES_USE_MAC */ mbedtls_cipher_context_t cipher_ctx_enc; /*!< encryption context */ mbedtls_cipher_context_t cipher_ctx_dec; /*!< decryption context */ int minor_ver; #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID) uint8_t in_cid_len; uint8_t out_cid_len; unsigned char in_cid [ MBEDTLS_SSL_CID_OUT_LEN_MAX ]; unsigned char out_cid[ MBEDTLS_SSL_CID_OUT_LEN_MAX ]; #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */ #if defined(MBEDTLS_SSL_CONTEXT_SERIALIZATION) /* We need the Hello random bytes in order to re-derive keys from the * Master Secret and other session info, * see ssl_tls12_populate_transform() */ unsigned char randbytes[MBEDTLS_SERVER_HELLO_RANDOM_LEN + MBEDTLS_CLIENT_HELLO_RANDOM_LEN]; /*!< ServerHello.random+ClientHello.random */ #endif /* MBEDTLS_SSL_CONTEXT_SERIALIZATION */ }; /* * Return 1 if the transform uses an AEAD cipher, 0 otherwise. * Equivalently, return 0 if a separate MAC is used, 1 otherwise. */ static inline int mbedtls_ssl_transform_uses_aead( const mbedtls_ssl_transform *transform ) { #if defined(MBEDTLS_SSL_SOME_SUITES_USE_MAC) return( transform->maclen == 0 && transform->taglen != 0 ); #else (void) transform; return( 1 ); #endif } /* * Internal representation of record frames * * Instances come in two flavors: * (1) Encrypted * These always have data_offset = 0 * (2) Unencrypted * These have data_offset set to the amount of * pre-expansion during record protection. Concretely, * this is the length of the fixed part of the explicit IV * used for encryption, or 0 if no explicit IV is used * (e.g. for stream ciphers). * * The reason for the data_offset in the unencrypted case * is to allow for in-place conversion of an unencrypted to * an encrypted record. If the offset wasn't included, the * encrypted content would need to be shifted afterwards to * make space for the fixed IV. * */ #if MBEDTLS_SSL_CID_OUT_LEN_MAX > MBEDTLS_SSL_CID_IN_LEN_MAX #define MBEDTLS_SSL_CID_LEN_MAX MBEDTLS_SSL_CID_OUT_LEN_MAX #else #define MBEDTLS_SSL_CID_LEN_MAX MBEDTLS_SSL_CID_IN_LEN_MAX #endif typedef struct { uint8_t ctr[MBEDTLS_SSL_SEQUENCE_NUMBER_LEN]; /* In TLS: The implicit record sequence number. * In DTLS: The 2-byte epoch followed by * the 6-byte sequence number. * This is stored as a raw big endian byte array * as opposed to a uint64_t because we rarely * need to perform arithmetic on this, but do * need it as a Byte array for the purpose of * MAC computations. */ uint8_t type; /* The record content type. */ uint8_t ver[2]; /* SSL/TLS version as present on the wire. * Convert to internal presentation of versions * using mbedtls_ssl_read_version() and * mbedtls_ssl_write_version(). * Keep wire-format for MAC computations. */ unsigned char *buf; /* Memory buffer enclosing the record content */ size_t buf_len; /* Buffer length */ size_t data_offset; /* Offset of record content */ size_t data_len; /* Length of record content */ #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID) uint8_t cid_len; /* Length of the CID (0 if not present) */ unsigned char cid[ MBEDTLS_SSL_CID_LEN_MAX ]; /* The CID */ #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */ } mbedtls_record; #if defined(MBEDTLS_X509_CRT_PARSE_C) /* * List of certificate + private key pairs */ struct mbedtls_ssl_key_cert { mbedtls_x509_crt *cert; /*!< cert */ mbedtls_pk_context *key; /*!< private key */ mbedtls_ssl_key_cert *next; /*!< next key/cert pair */ }; #endif /* MBEDTLS_X509_CRT_PARSE_C */ #if defined(MBEDTLS_SSL_PROTO_DTLS) /* * List of handshake messages kept around for resending */ struct mbedtls_ssl_flight_item { unsigned char *p; /*!< message, including handshake headers */ size_t len; /*!< length of p */ unsigned char type; /*!< type of the message: handshake or CCS */ mbedtls_ssl_flight_item *next; /*!< next handshake message(s) */ }; #endif /* MBEDTLS_SSL_PROTO_DTLS */ #if defined(MBEDTLS_SSL_PROTO_TLS1_2) && \ defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED) /* Find an entry in a signature-hash set matching a given hash algorithm. */ mbedtls_md_type_t mbedtls_ssl_sig_hash_set_find( mbedtls_ssl_sig_hash_set_t *set, mbedtls_pk_type_t sig_alg ); /* Add a signature-hash-pair to a signature-hash set */ void mbedtls_ssl_sig_hash_set_add( mbedtls_ssl_sig_hash_set_t *set, mbedtls_pk_type_t sig_alg, mbedtls_md_type_t md_alg ); /* Allow exactly one hash algorithm for each signature. */ void mbedtls_ssl_sig_hash_set_const_hash( mbedtls_ssl_sig_hash_set_t *set, mbedtls_md_type_t md_alg ); /* Setup an empty signature-hash set */ static inline void mbedtls_ssl_sig_hash_set_init( mbedtls_ssl_sig_hash_set_t *set ) { mbedtls_ssl_sig_hash_set_const_hash( set, MBEDTLS_MD_NONE ); } #endif /* MBEDTLS_SSL_PROTO_TLS1_2) && MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED */ /** * \brief Free referenced items in an SSL transform context and clear * memory * * \param transform SSL transform context */ void mbedtls_ssl_transform_free( mbedtls_ssl_transform *transform ); /** * \brief Free referenced items in an SSL handshake context and clear * memory * * \param ssl SSL context */ void mbedtls_ssl_handshake_free( mbedtls_ssl_context *ssl ); /* set inbound transform of ssl context */ void mbedtls_ssl_set_inbound_transform( mbedtls_ssl_context *ssl, mbedtls_ssl_transform *transform ); /* set outbound transform of ssl context */ void mbedtls_ssl_set_outbound_transform( mbedtls_ssl_context *ssl, mbedtls_ssl_transform *transform ); #if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION) int mbedtls_ssl_write_hostname_ext( mbedtls_ssl_context *ssl, unsigned char *buf, const unsigned char *end, size_t *olen ); #endif int mbedtls_ssl_handshake_client_step( mbedtls_ssl_context *ssl ); int mbedtls_ssl_handshake_server_step( mbedtls_ssl_context *ssl ); void mbedtls_ssl_handshake_wrapup( mbedtls_ssl_context *ssl ); #if defined(MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL) /** * \brief TLS 1.3 client side state machine entry * * \param ssl SSL context */ int mbedtls_ssl_tls13_handshake_client_step( mbedtls_ssl_context *ssl ); /** * \brief TLS 1.3 server side state machine entry * * \param ssl SSL context */ int mbedtls_ssl_tls13_handshake_server_step( mbedtls_ssl_context *ssl ); #endif int mbedtls_ssl_send_fatal_handshake_failure( mbedtls_ssl_context *ssl ); void mbedtls_ssl_reset_checksum( mbedtls_ssl_context *ssl ); int mbedtls_ssl_derive_keys( mbedtls_ssl_context *ssl ); int mbedtls_ssl_handle_message_type( mbedtls_ssl_context *ssl ); int mbedtls_ssl_prepare_handshake_record( mbedtls_ssl_context *ssl ); void mbedtls_ssl_update_handshake_status( mbedtls_ssl_context *ssl ); /** * \brief Update record layer * * This function roughly separates the implementation * of the logic of (D)TLS from the implementation * of the secure transport. * * \param ssl The SSL context to use. * \param update_hs_digest This indicates if the handshake digest * should be automatically updated in case * a handshake message is found. * * \return 0 or non-zero error code. * * \note A clarification on what is called 'record layer' here * is in order, as many sensible definitions are possible: * * The record layer takes as input an untrusted underlying * transport (stream or datagram) and transforms it into * a serially multiplexed, secure transport, which * conceptually provides the following: * * (1) Three datagram based, content-agnostic transports * for handshake, alert and CCS messages. * (2) One stream- or datagram-based transport * for application data. * (3) Functionality for changing the underlying transform * securing the contents. * * The interface to this functionality is given as follows: * * a Updating * [Currently implemented by mbedtls_ssl_read_record] * * Check if and on which of the four 'ports' data is pending: * Nothing, a controlling datagram of type (1), or application * data (2). In any case data is present, internal buffers * provide access to the data for the user to process it. * Consumption of type (1) datagrams is done automatically * on the next update, invalidating that the internal buffers * for previous datagrams, while consumption of application * data (2) is user-controlled. * * b Reading of application data * [Currently manual adaption of ssl->in_offt pointer] * * As mentioned in the last paragraph, consumption of data * is different from the automatic consumption of control * datagrams (1) because application data is treated as a stream. * * c Tracking availability of application data * [Currently manually through decreasing ssl->in_msglen] * * For efficiency and to retain datagram semantics for * application data in case of DTLS, the record layer * provides functionality for checking how much application * data is still available in the internal buffer. * * d Changing the transformation securing the communication. * * Given an opaque implementation of the record layer in the * above sense, it should be possible to implement the logic * of (D)TLS on top of it without the need to know anything * about the record layer's internals. This is done e.g. * in all the handshake handling functions, and in the * application data reading function mbedtls_ssl_read. * * \note The above tries to give a conceptual picture of the * record layer, but the current implementation deviates * from it in some places. For example, our implementation of * the update functionality through mbedtls_ssl_read_record * discards datagrams depending on the current state, which * wouldn't fall under the record layer's responsibility * following the above definition. * */ int mbedtls_ssl_read_record( mbedtls_ssl_context *ssl, unsigned update_hs_digest ); int mbedtls_ssl_fetch_input( mbedtls_ssl_context *ssl, size_t nb_want ); int mbedtls_ssl_write_handshake_msg_ext( mbedtls_ssl_context *ssl, int update_checksum ); static inline int mbedtls_ssl_write_handshake_msg( mbedtls_ssl_context *ssl ) { return( mbedtls_ssl_write_handshake_msg_ext( ssl, 1 /* update checksum */ ) ); } int mbedtls_ssl_write_record( mbedtls_ssl_context *ssl, uint8_t force_flush ); int mbedtls_ssl_flush_output( mbedtls_ssl_context *ssl ); int mbedtls_ssl_tls13_process_finished_message( mbedtls_ssl_context *ssl ); int mbedtls_ssl_tls13_write_finished_message( mbedtls_ssl_context *ssl ); int mbedtls_ssl_parse_certificate( mbedtls_ssl_context *ssl ); int mbedtls_ssl_write_certificate( mbedtls_ssl_context *ssl ); int mbedtls_ssl_parse_change_cipher_spec( mbedtls_ssl_context *ssl ); int mbedtls_ssl_write_change_cipher_spec( mbedtls_ssl_context *ssl ); int mbedtls_ssl_parse_finished( mbedtls_ssl_context *ssl ); int mbedtls_ssl_write_finished( mbedtls_ssl_context *ssl ); void mbedtls_ssl_optimize_checksum( mbedtls_ssl_context *ssl, const mbedtls_ssl_ciphersuite_t *ciphersuite_info ); #if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED) int mbedtls_ssl_psk_derive_premaster( mbedtls_ssl_context *ssl, mbedtls_key_exchange_type_t key_ex ); /** * Get the first defined PSK by order of precedence: * 1. handshake PSK set by \c mbedtls_ssl_set_hs_psk() in the PSK callback * 2. static PSK configured by \c mbedtls_ssl_conf_psk() * Return a code and update the pair (PSK, PSK length) passed to this function */ static inline int mbedtls_ssl_get_psk( const mbedtls_ssl_context *ssl, const unsigned char **psk, size_t *psk_len ) { if( ssl->handshake->psk != NULL && ssl->handshake->psk_len > 0 ) { *psk = ssl->handshake->psk; *psk_len = ssl->handshake->psk_len; } else if( ssl->conf->psk != NULL && ssl->conf->psk_len > 0 ) { *psk = ssl->conf->psk; *psk_len = ssl->conf->psk_len; } else { *psk = NULL; *psk_len = 0; return( MBEDTLS_ERR_SSL_PRIVATE_KEY_REQUIRED ); } return( 0 ); } #if defined(MBEDTLS_USE_PSA_CRYPTO) /** * Get the first defined opaque PSK by order of precedence: * 1. handshake PSK set by \c mbedtls_ssl_set_hs_psk_opaque() in the PSK * callback * 2. static PSK configured by \c mbedtls_ssl_conf_psk_opaque() * Return an opaque PSK */ static inline psa_key_id_t mbedtls_ssl_get_opaque_psk( const mbedtls_ssl_context *ssl ) { if( ! mbedtls_svc_key_id_is_null( ssl->handshake->psk_opaque ) ) return( ssl->handshake->psk_opaque ); if( ! mbedtls_svc_key_id_is_null( ssl->conf->psk_opaque ) ) return( ssl->conf->psk_opaque ); return( MBEDTLS_SVC_KEY_ID_INIT ); } #endif /* MBEDTLS_USE_PSA_CRYPTO */ #endif /* MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED */ #if defined(MBEDTLS_PK_C) unsigned char mbedtls_ssl_sig_from_pk( mbedtls_pk_context *pk ); unsigned char mbedtls_ssl_sig_from_pk_alg( mbedtls_pk_type_t type ); mbedtls_pk_type_t mbedtls_ssl_pk_alg_from_sig( unsigned char sig ); #endif mbedtls_md_type_t mbedtls_ssl_md_alg_from_hash( unsigned char hash ); unsigned char mbedtls_ssl_hash_from_md_alg( int md ); int mbedtls_ssl_set_calc_verify_md( mbedtls_ssl_context *ssl, int md ); #if defined(MBEDTLS_ECP_C) int mbedtls_ssl_check_curve( const mbedtls_ssl_context *ssl, mbedtls_ecp_group_id grp_id ); #endif #if defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED) int mbedtls_ssl_check_sig_hash( const mbedtls_ssl_context *ssl, mbedtls_md_type_t md ); #endif #if defined(MBEDTLS_SSL_DTLS_SRTP) static inline mbedtls_ssl_srtp_profile mbedtls_ssl_check_srtp_profile_value ( const uint16_t srtp_profile_value ) { switch( srtp_profile_value ) { case MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_80: case MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32: case MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_80: case MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_32: return srtp_profile_value; default: break; } return( MBEDTLS_TLS_SRTP_UNSET ); } #endif #if defined(MBEDTLS_X509_CRT_PARSE_C) static inline mbedtls_pk_context *mbedtls_ssl_own_key( mbedtls_ssl_context *ssl ) { mbedtls_ssl_key_cert *key_cert; if( ssl->handshake != NULL && ssl->handshake->key_cert != NULL ) key_cert = ssl->handshake->key_cert; else key_cert = ssl->conf->key_cert; return( key_cert == NULL ? NULL : key_cert->key ); } static inline mbedtls_x509_crt *mbedtls_ssl_own_cert( mbedtls_ssl_context *ssl ) { mbedtls_ssl_key_cert *key_cert; if( ssl->handshake != NULL && ssl->handshake->key_cert != NULL ) key_cert = ssl->handshake->key_cert; else key_cert = ssl->conf->key_cert; return( key_cert == NULL ? NULL : key_cert->cert ); } /* * Check usage of a certificate wrt extensions: * keyUsage, extendedKeyUsage (later), and nSCertType (later). * * Warning: cert_endpoint is the endpoint of the cert (ie, of our peer when we * check a cert we received from them)! * * Return 0 if everything is OK, -1 if not. */ int mbedtls_ssl_check_cert_usage( const mbedtls_x509_crt *cert, const mbedtls_ssl_ciphersuite_t *ciphersuite, int cert_endpoint, uint32_t *flags ); #endif /* MBEDTLS_X509_CRT_PARSE_C */ void mbedtls_ssl_write_version( int major, int minor, int transport, unsigned char ver[2] ); void mbedtls_ssl_read_version( int *major, int *minor, int transport, const unsigned char ver[2] ); static inline size_t mbedtls_ssl_in_hdr_len( const mbedtls_ssl_context *ssl ) { #if !defined(MBEDTLS_SSL_PROTO_DTLS) ((void) ssl); #endif #if defined(MBEDTLS_SSL_PROTO_DTLS) if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM ) { return( 13 ); } else #endif /* MBEDTLS_SSL_PROTO_DTLS */ { return( 5 ); } } static inline size_t mbedtls_ssl_out_hdr_len( const mbedtls_ssl_context *ssl ) { return( (size_t) ( ssl->out_iv - ssl->out_hdr ) ); } static inline size_t mbedtls_ssl_hs_hdr_len( const mbedtls_ssl_context *ssl ) { #if defined(MBEDTLS_SSL_PROTO_DTLS) if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM ) return( 12 ); #else ((void) ssl); #endif return( 4 ); } #if defined(MBEDTLS_SSL_PROTO_DTLS) void mbedtls_ssl_send_flight_completed( mbedtls_ssl_context *ssl ); void mbedtls_ssl_recv_flight_completed( mbedtls_ssl_context *ssl ); int mbedtls_ssl_resend( mbedtls_ssl_context *ssl ); int mbedtls_ssl_flight_transmit( mbedtls_ssl_context *ssl ); #endif /* Visible for testing purposes only */ #if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY) int mbedtls_ssl_dtls_replay_check( mbedtls_ssl_context const *ssl ); void mbedtls_ssl_dtls_replay_update( mbedtls_ssl_context *ssl ); #endif int mbedtls_ssl_session_copy( mbedtls_ssl_session *dst, const mbedtls_ssl_session *src ); /* constant-time buffer comparison */ static inline int mbedtls_ssl_safer_memcmp( const void *a, const void *b, size_t n ) { size_t i; volatile const unsigned char *A = (volatile const unsigned char *) a; volatile const unsigned char *B = (volatile const unsigned char *) b; volatile unsigned char diff = 0; for( i = 0; i < n; i++ ) { /* Read volatile data in order before computing diff. * This avoids IAR compiler warning: * 'the order of volatile accesses is undefined ..' */ unsigned char x = A[i], y = B[i]; diff |= x ^ y; } return( diff ); } #if defined(MBEDTLS_SSL_PROTO_TLS1_2) /* The hash buffer must have at least MBEDTLS_MD_MAX_SIZE bytes of length. */ int mbedtls_ssl_get_key_exchange_md_tls1_2( mbedtls_ssl_context *ssl, unsigned char *hash, size_t *hashlen, unsigned char *data, size_t data_len, mbedtls_md_type_t md_alg ); #endif /* MBEDTLS_SSL_PROTO_TLS1_2 */ #ifdef __cplusplus } #endif void mbedtls_ssl_transform_init( mbedtls_ssl_transform *transform ); int mbedtls_ssl_encrypt_buf( mbedtls_ssl_context *ssl, mbedtls_ssl_transform *transform, mbedtls_record *rec, int (*f_rng)(void *, unsigned char *, size_t), void *p_rng ); int mbedtls_ssl_decrypt_buf( mbedtls_ssl_context const *ssl, mbedtls_ssl_transform *transform, mbedtls_record *rec ); /* Length of the "epoch" field in the record header */ static inline size_t mbedtls_ssl_ep_len( const mbedtls_ssl_context *ssl ) { #if defined(MBEDTLS_SSL_PROTO_DTLS) if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM ) return( 2 ); #else ((void) ssl); #endif return( 0 ); } #if defined(MBEDTLS_SSL_PROTO_DTLS) int mbedtls_ssl_resend_hello_request( mbedtls_ssl_context *ssl ); #endif /* MBEDTLS_SSL_PROTO_DTLS */ void mbedtls_ssl_set_timer( mbedtls_ssl_context *ssl, uint32_t millisecs ); int mbedtls_ssl_check_timer( mbedtls_ssl_context *ssl ); void mbedtls_ssl_reset_in_out_pointers( mbedtls_ssl_context *ssl ); void mbedtls_ssl_update_out_pointers( mbedtls_ssl_context *ssl, mbedtls_ssl_transform *transform ); void mbedtls_ssl_update_in_pointers( mbedtls_ssl_context *ssl ); int mbedtls_ssl_session_reset_int( mbedtls_ssl_context *ssl, int partial ); /* * Send pending alert */ int mbedtls_ssl_handle_pending_alert( mbedtls_ssl_context *ssl ); /* * Set pending fatal alert flag. */ void mbedtls_ssl_pend_fatal_alert( mbedtls_ssl_context *ssl, unsigned char alert_type, int alert_reason ); /* Alias of mbedtls_ssl_pend_fatal_alert */ #define MBEDTLS_SSL_PEND_FATAL_ALERT( type, user_return_value ) \ mbedtls_ssl_pend_fatal_alert( ssl, type, user_return_value ) #if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY) void mbedtls_ssl_dtls_replay_reset( mbedtls_ssl_context *ssl ); #endif void mbedtls_ssl_handshake_wrapup_free_hs_transform( mbedtls_ssl_context *ssl ); #if defined(MBEDTLS_SSL_RENEGOTIATION) int mbedtls_ssl_start_renegotiation( mbedtls_ssl_context *ssl ); #endif /* MBEDTLS_SSL_RENEGOTIATION */ #if defined(MBEDTLS_SSL_PROTO_DTLS) size_t mbedtls_ssl_get_current_mtu( const mbedtls_ssl_context *ssl ); void mbedtls_ssl_buffering_free( mbedtls_ssl_context *ssl ); void mbedtls_ssl_flight_free( mbedtls_ssl_flight_item *flight ); #endif /* MBEDTLS_SSL_PROTO_DTLS */ #if defined(MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL) /* * Helper functions around key exchange modes. */ static inline unsigned mbedtls_ssl_conf_tls13_check_kex_modes( mbedtls_ssl_context *ssl, int kex_mode_mask ) { return( ( ssl->conf->tls13_kex_modes & kex_mode_mask ) != 0 ); } static inline int mbedtls_ssl_conf_tls13_psk_enabled( mbedtls_ssl_context *ssl ) { return( mbedtls_ssl_conf_tls13_check_kex_modes( ssl, MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_PSK ) ); } static inline int mbedtls_ssl_conf_tls13_psk_ephemeral_enabled( mbedtls_ssl_context *ssl ) { return( mbedtls_ssl_conf_tls13_check_kex_modes( ssl, MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_PSK_EPHEMERAL ) ); } static inline int mbedtls_ssl_conf_tls13_ephemeral_enabled( mbedtls_ssl_context *ssl ) { return( mbedtls_ssl_conf_tls13_check_kex_modes( ssl, MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_EPHEMERAL ) ); } static inline int mbedtls_ssl_conf_tls13_some_ephemeral_enabled( mbedtls_ssl_context *ssl ) { return( mbedtls_ssl_conf_tls13_check_kex_modes( ssl, MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_EPHEMERAL_ALL ) ); } static inline int mbedtls_ssl_conf_tls13_some_psk_enabled( mbedtls_ssl_context *ssl ) { return( mbedtls_ssl_conf_tls13_check_kex_modes( ssl, MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_PSK_ALL ) ); } /** * Given a list of key exchange modes, check if at least one of them is * supported. * * \param[in] ssl SSL context * \param kex_modes_mask Mask of the key exchange modes to check * * \return 0 if at least one of the key exchange modes is supported, * !=0 otherwise. */ static inline unsigned mbedtls_ssl_tls1_3_check_kex_modes( mbedtls_ssl_context *ssl, int kex_modes_mask ) { return( ( ssl->handshake->tls1_3_kex_modes & kex_modes_mask ) == 0 ); } static inline int mbedtls_ssl_tls1_3_psk_enabled( mbedtls_ssl_context *ssl ) { return( ! mbedtls_ssl_tls1_3_check_kex_modes( ssl, MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_PSK ) ); } static inline int mbedtls_ssl_tls1_3_psk_ephemeral_enabled( mbedtls_ssl_context *ssl ) { return( ! mbedtls_ssl_tls1_3_check_kex_modes( ssl, MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_PSK_EPHEMERAL ) ); } static inline int mbedtls_ssl_tls1_3_ephemeral_enabled( mbedtls_ssl_context *ssl ) { return( ! mbedtls_ssl_tls1_3_check_kex_modes( ssl, MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_EPHEMERAL ) ); } static inline int mbedtls_ssl_tls1_3_some_ephemeral_enabled( mbedtls_ssl_context *ssl ) { return( ! mbedtls_ssl_tls1_3_check_kex_modes( ssl, MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_EPHEMERAL_ALL ) ); } static inline int mbedtls_ssl_tls1_3_some_psk_enabled( mbedtls_ssl_context *ssl ) { return( ! mbedtls_ssl_tls1_3_check_kex_modes( ssl, MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_PSK_ALL ) ); } #endif /* MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL */ /** * ssl utils functions for checking configuration. */ #if defined(MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL) static inline int mbedtls_ssl_conf_is_tls13_only( const mbedtls_ssl_config *conf ) { if( conf->min_major_ver == MBEDTLS_SSL_MAJOR_VERSION_3 && conf->max_major_ver == MBEDTLS_SSL_MAJOR_VERSION_3 && conf->min_minor_ver == MBEDTLS_SSL_MINOR_VERSION_4 && conf->max_minor_ver == MBEDTLS_SSL_MINOR_VERSION_4 ) { return( 1 ); } return( 0 ); } #endif /* MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL */ #if defined(MBEDTLS_SSL_PROTO_TLS1_2) static inline int mbedtls_ssl_conf_is_tls12_only( const mbedtls_ssl_config *conf ) { if( conf->min_major_ver == MBEDTLS_SSL_MAJOR_VERSION_3 && conf->max_major_ver == MBEDTLS_SSL_MAJOR_VERSION_3 && conf->min_minor_ver == MBEDTLS_SSL_MINOR_VERSION_3 && conf->max_minor_ver == MBEDTLS_SSL_MINOR_VERSION_3 ) { return( 1 ); } return( 0 ); } #endif /* MBEDTLS_SSL_PROTO_TLS1_2 */ #if defined(MBEDTLS_SSL_PROTO_TLS1_2) && defined(MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL) static inline int mbedtls_ssl_conf_is_hybrid_tls12_tls13( const mbedtls_ssl_config *conf ) { if( conf->min_major_ver == MBEDTLS_SSL_MAJOR_VERSION_3 && conf->max_major_ver == MBEDTLS_SSL_MAJOR_VERSION_3 && conf->min_minor_ver == MBEDTLS_SSL_MINOR_VERSION_3 && conf->max_minor_ver == MBEDTLS_SSL_MINOR_VERSION_4 ) { return( 1 ); } return( 0 ); } #endif /* MBEDTLS_SSL_PROTO_TLS1_2 && MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL*/ #if defined(MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL) /* * Helper functions for NamedGroup. */ static inline int mbedtls_ssl_tls13_named_group_is_ecdhe( uint16_t named_group ) { return( named_group == MBEDTLS_SSL_IANA_TLS_GROUP_SECP256R1 || named_group == MBEDTLS_SSL_IANA_TLS_GROUP_SECP384R1 || named_group == MBEDTLS_SSL_IANA_TLS_GROUP_SECP521R1 || named_group == MBEDTLS_SSL_IANA_TLS_GROUP_X25519 || named_group == MBEDTLS_SSL_IANA_TLS_GROUP_X448 ); } static inline int mbedtls_ssl_tls13_named_group_is_dhe( uint16_t named_group ) { return( named_group >= MBEDTLS_SSL_IANA_TLS_GROUP_FFDHE2048 && named_group <= MBEDTLS_SSL_IANA_TLS_GROUP_FFDHE8192 ); } static inline void mbedtls_ssl_handshake_set_state( mbedtls_ssl_context *ssl, mbedtls_ssl_states state ) { ssl->state = ( int ) state; } /* * Fetch TLS 1.3 handshake message header */ int mbedtls_ssl_tls1_3_fetch_handshake_msg( mbedtls_ssl_context *ssl, unsigned hs_type, unsigned char **buf, size_t *buf_len ); /* * Write TLS 1.3 handshake message header */ int mbedtls_ssl_tls13_start_handshake_msg( mbedtls_ssl_context *ssl, unsigned hs_type, unsigned char **buf, size_t *buflen ); /* * Handler of TLS 1.3 server certificate message */ int mbedtls_ssl_tls13_process_certificate( mbedtls_ssl_context *ssl ); /* * Generic handler of Certificate Verify */ int mbedtls_ssl_tls13_process_certificate_verify( mbedtls_ssl_context *ssl ); /* * Write TLS 1.3 handshake message tail */ int mbedtls_ssl_tls13_finish_handshake_msg( mbedtls_ssl_context *ssl, size_t buf_len, size_t msg_len ); void mbedtls_ssl_tls13_add_hs_hdr_to_checksum( mbedtls_ssl_context *ssl, unsigned hs_type, size_t total_hs_len ); /* * Update checksum of handshake messages. */ void mbedtls_ssl_tls1_3_add_hs_msg_to_checksum( mbedtls_ssl_context *ssl, unsigned hs_type, unsigned char const *msg, size_t msg_len ); #if defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED) /* * Write TLS 1.3 Signature Algorithm extension */ int mbedtls_ssl_tls13_write_sig_alg_ext( mbedtls_ssl_context *ssl, unsigned char *buf, unsigned char *end, size_t *olen); #endif /* MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED */ #endif /* MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL */ /* Get handshake transcript */ int mbedtls_ssl_get_handshake_transcript( mbedtls_ssl_context *ssl, const mbedtls_md_type_t md, unsigned char *dst, size_t dst_len, size_t *olen ); /* * Return supported groups. * * In future, invocations can be changed to ssl->conf->group_list * when mbedtls_ssl_conf_curves() is deleted. * * ssl->handshake->group_list is either a translation of curve_list to IANA TLS group * identifiers when mbedtls_ssl_conf_curves() has been used, or a pointer to * ssl->conf->group_list when mbedtls_ssl_conf_groups() has been more recently invoked. * */ static inline const void *mbedtls_ssl_get_groups( const mbedtls_ssl_context *ssl ) { #if defined(MBEDTLS_DEPRECATED_REMOVED) || !defined(MBEDTLS_ECP_C) return( ssl->conf->group_list ); #else if( ( ssl->handshake != NULL ) && ( ssl->handshake->group_list != NULL ) ) return( ssl->handshake->group_list ); else return( ssl->conf->group_list ); #endif } #endif /* ssl_misc.h */