diff --git a/library/psa_crypto_core.h b/library/psa_crypto_core.h
index a53824e..f3f7dfb 100644
--- a/library/psa_crypto_core.h
+++ b/library/psa_crypto_core.h
@@ -911,4 +911,43 @@
  */
 void psa_crypto_input_copy_free(psa_crypto_input_copy_t *input_copy);
 
+typedef struct psa_crypto_output_copy_s {
+  uint8_t *original;
+  uint8_t *buffer;
+  size_t len;
+} psa_crypto_output_copy_t;
+
+/** Allocate a local copy of an output buffer.
+ *
+ * \note                        This does not copy any data from the original
+ *                              output buffer but only allocates a buffer
+ *                              whose contents will be copied back to the
+ *                              original in a future call to
+ *                              psa_crypto_output_copy_free().
+ *
+ * \param[in] output            Pointer to output buffer.
+ * \param[in] output_len        Length of the output buffer.
+ * \param[out] output_copy      Pointer to a psa_crypto_output_copy_t struct to
+ *                              populate with the output copy.
+ * \return                      #PSA_SUCCESS, if the buffer was successfully
+ *                              copied.
+ * \return                      #PSA_ERROR_INSUFFICIENT_MEMORY, if a copy of
+ *                              the buffer cannot be allocated.
+ */
+psa_status_t psa_crypto_output_copy_alloc(uint8_t *output, size_t output_len,
+                                          psa_crypto_output_copy_t *output_copy);
+
+/** Copy from a local copy of an output buffer back to the original, then
+ *  free the local copy.
+ *
+ * \param[in] output_copy       Pointer to a psa_crypto_output_copy_t struct
+ *                              populated by a previous call to
+ *                              psa_crypto_output_copy_alloc().
+ * \return                      #PSA_SUCCESS, if the output copy was
+ *                              successfully copied back to the original.
+ * \return                      #PSA_ERROR_CORRUPTION_DETECTED, if the output
+ *                              could not be copied back to the original.
+ */
+psa_status_t psa_crypto_output_copy_free(psa_crypto_output_copy_t *output_copy);
+
 #endif /* PSA_CRYPTO_CORE_H */