Expand documentation of internal mbedtls_record structure
diff --git a/include/mbedtls/ssl_internal.h b/include/mbedtls/ssl_internal.h
index c2bc3b7..4028abe 100644
--- a/include/mbedtls/ssl_internal.h
+++ b/include/mbedtls/ssl_internal.h
@@ -672,18 +672,29 @@
typedef struct
{
- uint8_t ctr[8]; /* Record sequence number */
- uint8_t type; /* Record type */
- uint8_t ver[2]; /* SSL/TLS version */
+ uint8_t ctr[8]; /* 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 */
+ 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 */
+ 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;
