Add buffers struct and prototypes for alloc API
Add function prototypes for psa_crypto_alloc_and_copy() and
psa_crypto_alloc_and_free(), along with the necessary state struct.
Signed-off-by: David Horstmann <david.horstmann@arm.com>
diff --git a/library/psa_crypto_core.h b/library/psa_crypto_core.h
index 4c38a75..78550f8 100644
--- a/library/psa_crypto_core.h
+++ b/library/psa_crypto_core.h
@@ -884,4 +884,57 @@
psa_status_t psa_crypto_copy_output(const uint8_t *output_copy, size_t output_copy_len,
uint8_t *output, size_t output_len);
+/**
+ * \brief Structure to store a pair of copied buffers (input, output) with a
+ * reference to the original output to be used during copy-back.
+ */
+struct psa_crypto_buffer_copy_s {
+ uint8_t *input;
+ size_t input_len;
+
+ uint8_t *output_original;
+ uint8_t *output;
+ size_t output_len;
+};
+typedef struct psa_crypto_buffer_copy_s psa_crypto_buffer_copy_t;
+
+/**
+ * \brief Allocate copies of provided input and output
+ * buffers and store references to them along with
+ * the original output buffer in the provided
+ * psa_crypto_buffer_copy_t struct.
+ * Either or both buffers may be NULL, in which case
+ * they are not copied.
+ *
+ * \note The input and output buffers may overlap.
+ *
+ * \param[in] input Pointer to the input buffer.
+ * \param[in] input_len Length of the input buffer.
+ * \param[in] output Pointer to the output buffer.
+ * \param[in] output_len Length of the output buffer.
+ * \param[out] buffers Struct containing pointers to the allocated
+ * copies and the original output buffer.
+ * \retval #PSA_SUCCESS
+ * The buffers were successfully allocated and copied.
+ * \retval #PSA_ERROR_INSUFFICIENT_MEMORY
+ * Failed to allocate buffers.
+ */
+psa_status_t psa_crypto_alloc_and_copy(const uint8_t *input, size_t input_len,
+ uint8_t *output, size_t output_len,
+ psa_crypto_buffer_copy_t *buffers);
+
+/**
+ * \brief Free an allocated pair of buffers after first
+ * copying the output buffer back to its original.
+ *
+ * \param[in] buffers psa_crypto_buffer_copy_t created by a previous
+ * call to psa_crypto_alloc_and_copy().
+ * \retval #PSA_SUCCESS
+ * The buffers were successfully copied-back and the
+ * copies freed.
+ * \retval #PSA_ERROR_INVALID_ARGUMENT
+ * Could not copy-back as \p buffers is invalid.
+ */
+psa_status_t psa_crypto_copy_and_free(psa_crypto_buffer_copy_t *buffers);
+
#endif /* PSA_CRYPTO_CORE_H */