Add accessor functions for cipher_info fields
Add functions to read the type, mode, name and key_bitlen fields from
mbedtls_cipher_info_t. These are the fields that applications are most
likely to care about.
TLS code also uses iv_size and block_size, which it might make sense to
expose, but most applications shouldn't need those, so I'm not exposing them
for now.
Call the new functions in unit tests, so they're at least smoke-tested.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/include/mbedtls/cipher.h b/include/mbedtls/cipher.h
index 9c9a2e8..7921f4d 100644
--- a/include/mbedtls/cipher.h
+++ b/include/mbedtls/cipher.h
@@ -415,6 +415,82 @@
const mbedtls_cipher_mode_t mode );
/**
+ * \brief Retrieve the identifier for a cipher info structure.
+ *
+ * \param[in] info The cipher info structure to query.
+ * This may be \c NULL.
+ *
+ * \return The full cipher identifier (\c MBEDTLS_CIPHER_xxx).
+ * \return #MBEDTLS_CIPHER_NONE if \p info is \c NULL.
+ */
+static inline mbedtls_cipher_type_t mbedtls_cipher_info_get_type(
+ const mbedtls_cipher_info_t *info )
+{
+ if( info == NULL )
+ return( MBEDTLS_CIPHER_NONE );
+ else
+ return( info->MBEDTLS_PRIVATE(type) );
+}
+
+/**
+ * \brief Retrieve the operation mode for a cipher info structure.
+ *
+ * \param[in] info The cipher info structure to query.
+ * This may be \c NULL.
+ *
+ * \return The cipher mode (\c MBEDTLS_MODE_xxx).
+ * \return #MBEDTLS_MODE_NONE if \p info is \c NULL.
+ */
+static inline mbedtls_cipher_mode_t mbedtls_cipher_info_get_mode(
+ const mbedtls_cipher_info_t *info )
+{
+ if( info == NULL )
+ return( MBEDTLS_MODE_NONE );
+ else
+ return( info->MBEDTLS_PRIVATE(mode) );
+}
+
+/**
+ * \brief Retrieve the key size for a cipher info structure.
+ *
+ * \param[in] info The cipher info structure to query.
+ * This may be \c NULL.
+ *
+ * \return The key length in bits.
+ * For variable-sized ciphers, this is the default length.
+ * For DES, this includes the parity bits.
+ * \return \c 0 if \p info is \c NULL.
+ */
+static inline size_t mbedtls_cipher_info_get_key_bitlen(
+ const mbedtls_cipher_info_t *info )
+{
+ if( info == NULL )
+ return( 0 );
+ else
+ return( info->MBEDTLS_PRIVATE(key_bitlen) );
+}
+
+/**
+ * \brief Retrieve the human-readable name for a
+ * cipher info structure.
+ *
+ * \param[in] info The cipher info structure to query.
+ * This may be \c NULL.
+ *
+ * \return The cipher name, which is a human readable string,
+ * with static storage duration.
+ * \return \c NULL if \c info is \p NULL.
+ */
+static inline const char *mbedtls_cipher_info_get_name(
+ const mbedtls_cipher_info_t *info )
+{
+ if( info == NULL )
+ return( NULL );
+ else
+ return( info->MBEDTLS_PRIVATE(name) );
+}
+
+/**
* \brief This function initializes a \p cipher_context as NONE.
*
* \param ctx The context to be initialized. This must not be \c NULL.