Fix content and style of constraints documentation
Be specific about the constraints: be a readable/writable buffer of length
X, be an initialized context, be a context initialized and bound to a key...
Always use full sentences with all the required pronouns.
@@ -121,14 +121,16 @@ typedef struct mbedtls_aes_xts_context
* It must be the first API called before using
* the context.
*
- * \param ctx The AES context to initialize. Must not be \c NULL.
+ * \param ctx The AES context to initialize. This must not be \c NULL.
*/
void mbedtls_aes_init( mbedtls_aes_context *ctx );
/**
* \brief This function releases and clears the specified AES context.
*
- * \param ctx The AES context to clear. If \c NULL, no action is taken.
+ * \param ctx The AES context to clear.
+ * If this is \c NULL, this function does nothing.
+ * Otherwise, the context must have been at least initialized.
*/
void mbedtls_aes_free( mbedtls_aes_context *ctx );
@@ -139,14 +141,16 @@ void mbedtls_aes_free( mbedtls_aes_context *ctx );
* It must be the first API called before using
* the context.
*
- * \param ctx The AES XTS context to initialize. Must not be \c NULL.
+ * \param ctx The AES XTS context to initialize. This must not be \c NULL.
*/
void mbedtls_aes_xts_init( mbedtls_aes_xts_context *ctx );
/**
* \brief This function releases and clears the specified AES XTS context.
*
- * \param ctx The AES XTS context to clear. If \c NULL, no action is taken.
+ * \param ctx The AES XTS context to clear.
+ * If this is \c NULL, this function does nothing.
+ * Otherwise, the context must have been at least initialized.
*/
void mbedtls_aes_xts_free( mbedtls_aes_xts_context *ctx );
#endif /* MBEDTLS_CIPHER_MODE_XTS */
@@ -154,9 +158,10 @@ void mbedtls_aes_xts_free( mbedtls_aes_xts_context *ctx );
/**
* \brief This function sets the encryption key.
*
- * \param ctx The AES context to which the key should be bound. Must not
- * be \c NULL.
- * \param key The encryption key. Must not be \c NULL.
+ * \param ctx The AES context to which the key should be bound.
+ * It must be initialized.
+ * \param key The encryption key.
+ * This must be a readable buffer of size \p keybits bits.
* \param keybits The size of data passed in bits. Valid options are:
* <ul><li>128 bits</li>
* <li>192 bits</li>
@@ -171,9 +176,10 @@ int mbedtls_aes_setkey_enc( mbedtls_aes_context *ctx, const unsigned char *key,
/**
* \brief This function sets the decryption key.
*
- * \param ctx The AES context to which the key should be bound. Must not
- * be \c NULL.
- * \param key The decryption key. Must not be \c NULL.
+ * \param ctx The AES context to which the key should be bound.
+ * It must be initialized.
+ * \param key The decryption key.
+ * This must be a readable buffer of size \p keybits bits.
* \param keybits The size of data passed. Valid options are:
* <ul><li>128 bits</li>
* <li>192 bits</li>
