Copy input and output in psa_cipher_encrypt()

Signed-off-by: David Horstmann <david.horstmann@arm.com>
diff --git a/library/psa_crypto.c b/library/psa_crypto.c
index ddc834f..36c5f75 100644
--- a/library/psa_crypto.c
+++ b/library/psa_crypto.c
@@ -4346,6 +4346,20 @@
     size_t default_iv_length = 0;
     psa_key_attributes_t attributes;
 
+    psa_crypto_local_input_t local_input = PSA_CRYPTO_LOCAL_INPUT_INIT;
+    status = psa_crypto_local_input_alloc(input, input_length, &local_input);
+    if (status != PSA_SUCCESS) {
+        goto exit;
+    }
+    input = local_input.buffer;
+
+    psa_crypto_local_output_t local_output = PSA_CRYPTO_LOCAL_OUTPUT_INIT;
+    status = psa_crypto_local_output_alloc(output, output_size, &local_output);
+    if (status != PSA_SUCCESS) {
+        goto exit;
+    }
+    output = local_output.buffer;
+
     if (!PSA_ALG_IS_CIPHER(alg)) {
         status = PSA_ERROR_INVALID_ARGUMENT;
         goto exit;
@@ -4401,6 +4415,9 @@
         *output_length = 0;
     }
 
+    psa_crypto_local_input_free(&local_input);
+    psa_crypto_local_output_free(&local_output);
+
     return status;
 }