Implement support for MTU setting

This commit is contained in:
Manuel Pégourié-Gonnard 2017-09-21 13:49:50 +02:00
parent 0b1d9b2c75
commit 9468ff1966
2 changed files with 92 additions and 20 deletions

View file

@ -2430,6 +2430,7 @@ void mbedtls_ssl_conf_cert_req_ca_list( mbedtls_ssl_config *conf,
#if defined(MBEDTLS_SSL_PROTO_DTLS)
/**
* \brief Set the Maximum Tranport Unit (MTU).
* Special value: 0 means unset (no limit).
* This represents the maximum size of a datagram payload
* handled by the transport layer (usually UDP) as determined
* by the network link and stack. In practice, this controls
@ -2446,7 +2447,8 @@ void mbedtls_ssl_conf_cert_req_ca_list( mbedtls_ssl_config *conf,
*
* \note Values larger than \c MBEDTLS_SSL_OUT_CONTENT_LEN have no
* effect. This can only be used to decrease the maximum size
* of detagrams sent.
* of datagrams sent. Values lower than record layer expansion
* are ignored.
*
* \param conf SSL configuration
* \param mtu Value of the path MTU in bytes
@ -2738,6 +2740,9 @@ const char *mbedtls_ssl_get_version( const mbedtls_ssl_context *ssl );
* \brief Return the (maximum) number of bytes added by the record
* layer: header + encryption/MAC overhead (inc. padding)
*
* \note This function is not available (always returns an error)
* when record compression is enabled.
*
* \param ssl SSL context
*
* \return Current maximum record expansion in bytes, or
@ -2752,12 +2757,8 @@ int mbedtls_ssl_get_record_expansion( const mbedtls_ssl_context *ssl );
* This is the value negotiated with peer if any,
* or the locally configured value.
*
* \note With DTLS, \c mbedtls_ssl_write() will return an error if
* called with a larger length value.
* With TLS, \c mbedtls_ssl_write() will fragment the input if
* necessary and return the number of bytes written; it is up
* to the caller to call \c mbedtls_ssl_write() again in
* order to send the remaining bytes if any.
* \sa mbedtls_ssl_conf_max_frag_len()
* \sa mbedtls_ssl_get_max_record_payload()
*
* \param ssl SSL context
*
@ -2766,6 +2767,34 @@ int mbedtls_ssl_get_record_expansion( const mbedtls_ssl_context *ssl );
size_t mbedtls_ssl_get_max_frag_len( const mbedtls_ssl_context *ssl );
#endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */
/**
* \brief Return the current maximum outgoing record payload in bytes.
* This takes into account the config.h setting \c
* MBEDTLS_SSL_OUT_CONTENT_LEN, the configured and negotiated
* max fragment length extension if used, and for DTLS the
* path MTU as configured and current record expansion.
*
* \note With DTLS, \c mbedtls_ssl_write() will return an error if
* called with a larger length value.
* With TLS, \c mbedtls_ssl_write() will fragment the input if
* necessary and return the number of bytes written; it is up
* to the caller to call \c mbedtls_ssl_write() again in
* order to send the remaining bytes if any.
*
* \note This function is not available (always returns an error)
* when record compression is enabled.
*
* \sa mbedtls_ssl_conf_mtu()
* \sa mbedtls_ssl_get_max_frag_len()
* \sa mbedtls_ssl_get_record_expansion()
*
* \param ssl SSL context
*
* \return Current maximum payload for an outgoing record,
* or a negative error code.
*/
int mbedtls_ssl_get_max_out_record_payload( const mbedtls_ssl_context *ssl );
#if defined(MBEDTLS_X509_CRT_PARSE_C)
/**
* \brief Return the peer certificate from the current connection