Add finish buffer size test

Signed-off-by: Paul Elliott <paul.elliott@arm.com>
diff --git a/tests/suites/test_suite_psa_crypto.data b/tests/suites/test_suite_psa_crypto.data
index 45d37b6..d223537 100644
--- a/tests/suites/test_suite_psa_crypto.data
+++ b/tests/suites/test_suite_psa_crypto.data
@@ -2626,22 +2626,35 @@
 depends_on:PSA_WANT_ALG_CHACHA20_POLY1305:PSA_WANT_KEY_TYPE_CHACHA20
 aead_multipart_set_nonce:PSA_KEY_TYPE_CHACHA20:"808182838485868788898a8b8c8d8e8f909192939495969798999a9b9c9d9e9f":PSA_ALG_CHACHA20_POLY1305:16:"":"":PSA_ERROR_INVALID_ARGUMENT
 
-PSA AEAD buffer test: AES - GCM, IN = 16, BUF = 10
+PSA AEAD output buffer test: AES - GCM, IN = 16, BUF = 10
 depends_on:PSA_WANT_ALG_GCM:PSA_WANT_KEY_TYPE_AES
 aead_multipart_update_buffer_test:PSA_KEY_TYPE_AES:"fbc0b4c56a714c83217b2d1bcadd2ed2e9efb0dcac6cc19f":PSA_ALG_AEAD_WITH_SHORTENED_TAG(PSA_ALG_GCM,16):10:"5f4b43e811da9c470d6a9b01":"":"d2ae38c4375954835d75b8e4c2f9bbb4":PSA_ERROR_BUFFER_TOO_SMALL
 
-PSA AEAD buffer test: AES - GCM, IN = 16, BUF = 16
+PSA AEAD output buffer test: AES - GCM, IN = 16, BUF = 16
 depends_on:PSA_WANT_ALG_GCM:PSA_WANT_KEY_TYPE_AES
 aead_multipart_update_buffer_test:PSA_KEY_TYPE_AES:"fbc0b4c56a714c83217b2d1bcadd2ed2e9efb0dcac6cc19f":PSA_ALG_AEAD_WITH_SHORTENED_TAG(PSA_ALG_GCM,16):16:"5f4b43e811da9c470d6a9b01":"":"d2ae38c4375954835d75b8e4c2f9bbb4":PSA_SUCCESS
 
-PSA AEAD buffer test: ChaCha20 - Poly1305 IN = 130, BUF = 10
+PSA AEAD output buffer test: ChaCha20 - Poly1305 IN = 130, BUF = 10
 depends_on:PSA_WANT_ALG_CHACHA20_POLY1305:PSA_WANT_KEY_TYPE_CHACHA20
 aead_multipart_update_buffer_test:PSA_KEY_TYPE_CHACHA20:"808182838485868788898a8b8c8d8e8f909192939495969798999a9b9c9d9e9f":PSA_ALG_CHACHA20_POLY1305:10:"070000004041424344454647":"50515253c0c1c2c3c4c5c6c7":"d31a8d34648e60db7b86afbc53ef7ec2a4aded51296e08fea9e2b5a736ee62d63dbea45e8ca9671282fafb69da92728b1a71de0a9e060b2905d6a5b67ecd3b3692ddbd7f2d778b8c9803aee328091b58fab324e4fad675945585808b4831d7bc3ff4def08e4b7a9de576d26586cec64b61161ae10b594f09e26a7e902ecbd0600691":PSA_ERROR_BUFFER_TOO_SMALL
 
-PSA AEAD buffer test: ChaCha20 - Poly1305 IN = 130, BUF = 130
+PSA AEAD output buffer test: ChaCha20 - Poly1305 IN = 130, BUF = 130
 depends_on:PSA_WANT_ALG_CHACHA20_POLY1305:PSA_WANT_KEY_TYPE_CHACHA20
 aead_multipart_update_buffer_test:PSA_KEY_TYPE_CHACHA20:"808182838485868788898a8b8c8d8e8f909192939495969798999a9b9c9d9e9f":PSA_ALG_CHACHA20_POLY1305:130:"070000004041424344454647":"50515253c0c1c2c3c4c5c6c7":"d31a8d34648e60db7b86afbc53ef7ec2a4aded51296e08fea9e2b5a736ee62d63dbea45e8ca9671282fafb69da92728b1a71de0a9e060b2905d6a5b67ecd3b3692ddbd7f2d778b8c9803aee328091b58fab324e4fad675945585808b4831d7bc3ff4def08e4b7a9de576d26586cec64b61161ae10b594f09e26a7e902ecbd0600691":PSA_SUCCESS
 
+PSA AEAD finish buffer test: AES - GCM, BUF = 8
+depends_on:PSA_WANT_ALG_GCM:PSA_WANT_KEY_TYPE_AES
+aead_multipart_finish_buffer_test:PSA_KEY_TYPE_AES:"fbc0b4c56a714c83217b2d1bcadd2ed2e9efb0dcac6cc19f":PSA_ALG_AEAD_WITH_SHORTENED_TAG(PSA_ALG_GCM,16):8:"5f4b43e811da9c470d6a9b01":"":"d2ae38c4375954835d75b8e4c2f9bbb4":PSA_ERROR_BUFFER_TOO_SMALL
+
+PSA AEAD finish buffer test: AES - GCM, BUF = 15
+depends_on:PSA_WANT_ALG_GCM:PSA_WANT_KEY_TYPE_AES
+aead_multipart_finish_buffer_test:PSA_KEY_TYPE_AES:"fbc0b4c56a714c83217b2d1bcadd2ed2e9efb0dcac6cc19f":PSA_ALG_AEAD_WITH_SHORTENED_TAG(PSA_ALG_GCM,16):15:"5f4b43e811da9c470d6a9b01":"":"d2ae38c4375954835d75b8e4c2f9bbb4":PSA_SUCCESS
+
+PSA AEAD finish buffer test: ChaCha20 - Poly1305, BUF = 0
+depends_on:PSA_WANT_ALG_CHACHA20_POLY1305:PSA_WANT_KEY_TYPE_CHACHA20
+aead_multipart_finish_buffer_test:PSA_KEY_TYPE_CHACHA20:"808182838485868788898a8b8c8d8e8f909192939495969798999a9b9c9d9e9f":PSA_ALG_CHACHA20_POLY1305:0:"070000004041424344454647":"50515253c0c1c2c3c4c5c6c7":"d31a8d34648e60db7b86afbc53ef7ec2a4aded51296e08fea9e2b5a736ee62d63dbea45e8ca9671282fafb69da92728b1a71de0a9e060b2905d6a5b67ecd3b3692ddbd7f2d778b8c9803aee328091b58fab324e4fad675945585808b4831d7bc3ff4def08e4b7a9de576d26586cec64b61161ae10b594f09e26a7e902ecbd0600691":PSA_SUCCESS
+
+
 PSA Multipart State Checks, AES - GCM
 depends_on:PSA_WANT_ALG_GCM:PSA_WANT_KEY_TYPE_AES
 aead_multipart_state_test:PSA_KEY_TYPE_AES:"C0C1C2C3C4C5C6C7C8C9CACBCCCDCECF":PSA_ALG_GCM:"000102030405060708090A0B0C0D0E0F":"000102030405060708090A0B":"0C0D0E0F101112131415161718191A1B1C1D1E"
diff --git a/tests/suites/test_suite_psa_crypto.function b/tests/suites/test_suite_psa_crypto.function
index 32be56e..b8023ee 100644
--- a/tests/suites/test_suite_psa_crypto.function
+++ b/tests/suites/test_suite_psa_crypto.function
@@ -3950,6 +3950,87 @@
 }
 /* END_CASE */
 
+/* BEGIN_CASE */
+void aead_multipart_finish_buffer_test( int key_type_arg, data_t *key_data,
+                                        int alg_arg,
+                                        int buffer_size,
+                                        data_t *nonce,
+                                        data_t *additional_data,
+                                        data_t *input_data,
+                                        int expected_status_arg )
+{
+
+    mbedtls_svc_key_id_t key = MBEDTLS_SVC_KEY_ID_INIT;
+    psa_key_type_t key_type = key_type_arg;
+    psa_algorithm_t alg = alg_arg;
+    psa_aead_operation_t operation;
+    psa_key_attributes_t attributes = PSA_KEY_ATTRIBUTES_INIT;
+    psa_status_t status = PSA_ERROR_GENERIC_ERROR;
+    psa_status_t expected_status = expected_status_arg;
+    unsigned char *output_data = NULL;
+    unsigned char *final_data = NULL;
+    size_t output_size = 0;
+    size_t output_length = 0;
+    size_t tag_length = 0;
+    uint8_t tag_buffer[PSA_AEAD_TAG_MAX_SIZE];
+
+    PSA_ASSERT( psa_crypto_init( ) );
+
+    psa_set_key_usage_flags( &attributes, PSA_KEY_USAGE_ENCRYPT  );
+    psa_set_key_algorithm( &attributes, alg );
+    psa_set_key_type( &attributes, key_type );
+
+    PSA_ASSERT( psa_import_key( &attributes, key_data->x, key_data->len,
+                                &key ) );
+
+    PSA_ASSERT( psa_get_key_attributes( key, &attributes ) );
+
+    output_size = PSA_AEAD_UPDATE_OUTPUT_SIZE( key_type, alg, input_data->len );
+
+    ASSERT_ALLOC( output_data, output_size );
+
+    TEST_ASSERT( buffer_size <= PSA_AEAD_FINISH_OUTPUT_MAX_SIZE );
+
+    ASSERT_ALLOC( final_data, buffer_size );
+
+    operation = psa_aead_operation_init( );
+
+    status = psa_aead_encrypt_setup( &operation, key, alg );
+
+    /* If the operation is not supported, just skip and not fail in case the
+     * encryption involves a common limitation of cryptography hardwares and
+     * an alternative implementation. */
+    if( status == PSA_ERROR_NOT_SUPPORTED )
+    {
+        MBEDTLS_TEST_PSA_SKIP_IF_ALT_AES_192( key_type, key_data->len * 8 );
+        MBEDTLS_TEST_PSA_SKIP_IF_ALT_GCM_NOT_12BYTES_NONCE( alg, nonce->len );
+    }
+
+    PSA_ASSERT( status );
+
+    PSA_ASSERT( psa_aead_set_nonce( &operation, nonce->x, nonce->len ) );
+
+    PSA_ASSERT( psa_aead_update_ad( &operation, additional_data->x,
+                                    additional_data->len ) );
+
+    PSA_ASSERT( psa_aead_update( &operation, input_data->x, input_data->len,
+                              output_data, output_size, &output_length ) );
+
+    /* Ensure we can still complete operation. */
+    status = psa_aead_finish( &operation, final_data, buffer_size,
+                              &output_length, tag_buffer,
+                              PSA_AEAD_TAG_MAX_SIZE, &tag_length );
+
+    TEST_EQUAL( status, expected_status );
+
+exit:
+    psa_destroy_key( key );
+    mbedtls_free( output_data );
+    mbedtls_free( final_data );
+    psa_aead_abort( &operation );
+    PSA_DONE( );
+}
+/* END_CASE */
 
 /* BEGIN_CASE */
 void aead_multipart_state_test( int key_type_arg, data_t *key_data,