Remove ref to CID from inner plaintext parsing/building functions
The internal functions
`ssl_cid_{build/parse}_inner_plaintext()`
implement the TLSInnerPlaintext mechanism used by DTLS 1.2 + CID
in order to allow for flexible length padding and to protect the
true content type of a record.
This feature is also present in TLS 1.3 support for which is under
development. As a preparatory step towards sharing the code between
the case of DTLS 1.2 + CID and TLS 1.3, this commit renames
`ssl_cid_{build/parse}_inner_plaintext()`
to
`ssl_{build/parse}_inner_plaintext()`.
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
diff --git a/library/ssl_msg.c b/library/ssl_msg.c
index 976fc7b..e5331a7 100644
--- a/library/ssl_msg.c
+++ b/library/ssl_msg.c
@@ -342,14 +342,16 @@
*/
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
-/* This functions transforms a DTLS plaintext fragment and a record content
- * type into an instance of the DTLSInnerPlaintext structure:
+/* This functions transforms a (D)TLS plaintext fragment and a record content
+ * type into an instance of the (D)TLSInnerPlaintext structure. This is used
+ * in DTLS 1.2 + CID and within TLS 1.3 to allow flexible padding and to protect
+ * a record's content type.
*
* struct {
* opaque content[DTLSPlaintext.length];
* ContentType real_type;
* uint8 zeros[length_of_padding];
- * } DTLSInnerPlaintext;
+ * } (D)TLSInnerPlaintext;
*
* Input:
* - `content`: The beginning of the buffer holding the
@@ -360,18 +362,18 @@
* - `rec_type`: The desired record content type.
*
* Output:
- * - `content`: The beginning of the resulting DTLSInnerPlaintext structure.
- * - `*content_size`: The length of the resulting DTLSInnerPlaintext structure.
+ * - `content`: The beginning of the resulting (D)TLSInnerPlaintext structure.
+ * - `*content_size`: The length of the resulting (D)TLSInnerPlaintext structure.
*
* Returns:
* - `0` on success.
* - A negative error code if `max_len` didn't offer enough space
* for the expansion.
*/
-static int ssl_cid_build_inner_plaintext( unsigned char *content,
- size_t *content_size,
- size_t remaining,
- uint8_t rec_type )
+static int ssl_build_inner_plaintext( unsigned char *content,
+ size_t *content_size,
+ size_t remaining,
+ uint8_t rec_type )
{
size_t len = *content_size;
size_t pad = ( MBEDTLS_SSL_CID_PADDING_GRANULARITY -
@@ -395,9 +397,9 @@
return( 0 );
}
-/* This function parses a DTLSInnerPlaintext structure.
- * See ssl_cid_build_inner_plaintext() for details. */
-static int ssl_cid_parse_inner_plaintext( unsigned char const *content,
+/* This function parses a (D)TLSInnerPlaintext structure.
+ * See ssl_build_inner_plaintext() for details. */
+static int ssl_parse_inner_plaintext( unsigned char const *content,
size_t *content_size,
uint8_t *rec_type )
{
@@ -586,12 +588,12 @@
{
/*
* Wrap plaintext into DTLSInnerPlaintext structure.
- * See ssl_cid_build_inner_plaintext() for more information.
+ * See ssl_build_inner_plaintext() for more information.
*
* Note that this changes `rec->data_len`, and hence
* `post_avail` needs to be recalculated afterwards.
*/
- if( ssl_cid_build_inner_plaintext( data,
+ if( ssl_build_inner_plaintext( data,
&rec->data_len,
post_avail,
rec->type ) != 0 )
@@ -1552,8 +1554,8 @@
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
if( rec->cid_len != 0 )
{
- ret = ssl_cid_parse_inner_plaintext( data, &rec->data_len,
- &rec->type );
+ ret = ssl_parse_inner_plaintext( data, &rec->data_len,
+ &rec->type );
if( ret != 0 )
return( MBEDTLS_ERR_SSL_INVALID_RECORD );
}