tests: Get rid of mbedtls_test_unhexify() in unit test code

In test functions calling mbedtls_test_unhexify(), change the
type of the associated parameters from `char*` to `data_t`.

That way the `unhexify` operation is done by the test
framework and not by the unit test code.

Use for the new parameters of type data_t the name of the
local variable that used to store the `unhexify` version of
the `char*` parameter.

Signed-off-by: Ronald Cron <ronald.cron@arm.com>
diff --git a/tests/suites/test_suite_nist_kw.function b/tests/suites/test_suite_nist_kw.function
index 15370b2..6a81052 100644
--- a/tests/suites/test_suite_nist_kw.function
+++ b/tests/suites/test_suite_nist_kw.function
@@ -242,42 +242,31 @@
 /* END_CASE */
 
 /* BEGIN_CASE */
-void mbedtls_nist_kw_wrap( int cipher_id, int mode,
-                           char *key_hex, char *msg_hex,
-                           char *expected_result_hex )
+void mbedtls_nist_kw_wrap( int cipher_id, int mode, data_t *key, data_t *msg,
+                           data_t *expected_result )
 {
-    unsigned char key[32];
-    unsigned char msg[512];
     unsigned char result[528];
-    unsigned char expected_result[528];
     mbedtls_nist_kw_context ctx;
-    size_t key_len, msg_len, result_len, expected_result_len, i, padlen;
+    size_t result_len, i, padlen;
 
     mbedtls_nist_kw_init( &ctx );
 
-    memset( key, 0x00, sizeof( key ) );
-    memset( msg, 0x00, sizeof( msg ) );
     memset( result, '+', sizeof( result ) );
 
-    key_len = mbedtls_test_unhexify( key, key_hex );
-    msg_len = mbedtls_test_unhexify( msg, msg_hex );
-    expected_result_len = mbedtls_test_unhexify( expected_result, expected_result_hex );
-    result_len = sizeof( result );
-
-    TEST_ASSERT( mbedtls_nist_kw_setkey( &ctx, cipher_id, key, key_len * 8, 1 )
-                 == 0 );
+    TEST_ASSERT( mbedtls_nist_kw_setkey( &ctx, cipher_id,
+                                         key->x, key->len * 8, 1 ) == 0 );
 
     /* Test with input == output */
-    TEST_ASSERT( mbedtls_nist_kw_wrap( &ctx, mode, msg, msg_len,
+    TEST_ASSERT( mbedtls_nist_kw_wrap( &ctx, mode, msg->x, msg->len,
                  result, &result_len, sizeof( result ) ) == 0 );
 
-    TEST_ASSERT( result_len == expected_result_len );
+    TEST_ASSERT( result_len == expected_result->len );
 
-    TEST_ASSERT( memcmp( expected_result, result, expected_result_len ) == 0 );
+    TEST_ASSERT( memcmp( expected_result->x, result, result_len ) == 0 );
 
-    padlen = ( msg_len % 8 != 0 ) ? 8 - (msg_len % 8 ) : 0;
+    padlen = ( msg->len % 8 != 0 ) ? 8 - (msg->len % 8 ) : 0;
     /* Check that the function didn't write beyond the end of the buffer. */
-    for( i = msg_len + 8 + padlen; i < sizeof( result ); i++ )
+    for( i = msg->len + 8 + padlen; i < sizeof( result ); i++ )
     {
         TEST_ASSERT( result[i] == '+' );
     }
@@ -288,39 +277,27 @@
 /* END_CASE */
 
 /* BEGIN_CASE */
-void mbedtls_nist_kw_unwrap( int cipher_id, int mode,
-                             char *key_hex, char *msg_hex,
-                             char *expected_result_hex, int expected_ret )
+void mbedtls_nist_kw_unwrap( int cipher_id, int mode, data_t *key, data_t *msg,
+                             data_t *expected_result, int expected_ret )
 {
-    unsigned char key[32];
-    unsigned char msg[528];
     unsigned char result[528];
-    unsigned char expected_result[528];
     mbedtls_nist_kw_context ctx;
-    size_t key_len, msg_len, result_len, expected_result_len, i;
+    size_t result_len, i;
 
     mbedtls_nist_kw_init( &ctx );
 
-    memset( key, 0x00, sizeof( key ) );
-    memset( msg, 0x00, sizeof( msg ) );
     memset( result, '+', sizeof( result ) );
-    memset( expected_result, 0x00, sizeof( expected_result ) );
 
-    key_len = mbedtls_test_unhexify( key, key_hex );
-    msg_len = mbedtls_test_unhexify( msg, msg_hex );
-    expected_result_len = mbedtls_test_unhexify( expected_result, expected_result_hex );
-    result_len = sizeof( result );
-
-    TEST_ASSERT( mbedtls_nist_kw_setkey( &ctx, cipher_id, key, key_len * 8, 0 )
-                 == 0 );
+    TEST_ASSERT( mbedtls_nist_kw_setkey( &ctx, cipher_id,
+                                         key->x, key->len * 8, 0 ) == 0 );
 
     /* Test with input == output */
-    TEST_ASSERT( mbedtls_nist_kw_unwrap( &ctx, mode, msg, msg_len,
+    TEST_ASSERT( mbedtls_nist_kw_unwrap( &ctx, mode, msg->x, msg->len,
                  result, &result_len, sizeof( result ) ) == expected_ret );
     if( expected_ret == 0 )
     {
-        TEST_ASSERT( result_len == expected_result_len );
-        TEST_ASSERT( memcmp( expected_result, result, expected_result_len ) == 0 );
+        TEST_ASSERT( result_len == expected_result->len );
+        TEST_ASSERT( memcmp( expected_result->x, result, result_len ) == 0 );
     }
     else
     {
@@ -328,7 +305,7 @@
     }
 
     /* Check that the function didn't write beyond the end of the buffer. */
-    for( i = msg_len - 8; i < sizeof( result ); i++ )
+    for( i = msg->len - 8; i < sizeof( result ); i++ )
     {
         TEST_ASSERT( result[i] == '+' );
     }