Add tests for the nist key wrapping feature

Add tests for Key wrapping.
Test vectors taken from the standards.
diff --git a/tests/suites/test_suite_nist_kw.function b/tests/suites/test_suite_nist_kw.function
new file mode 100644
index 0000000..eb67c03
--- /dev/null
+++ b/tests/suites/test_suite_nist_kw.function
@@ -0,0 +1,343 @@
+/* BEGIN_HEADER */
+#include "mbedtls/nist_kw.h"
+/* END_HEADER */
+
+/* BEGIN_DEPENDENCIES
+ * depends_on:MBEDTLS_NIST_KW_C
+ * END_DEPENDENCIES
+ */
+
+/* BEGIN_CASE depends_on:MBEDTLS_SELF_TEST:MBEDTLS_AES_C */
+void mbedtls_nist_kw_self_test( )
+{
+    TEST_ASSERT( mbedtls_nist_kw_self_test( 1 ) == 0 );
+}
+/* END_CASE */
+
+/* BEGIN_CASE depends_on:MBEDTLS_AES_C */
+void mbedtls_nist_kw_mix_contexts( )
+{
+    mbedtls_nist_kw_context ctx1, ctx2;
+    unsigned char key[16];
+    unsigned char plaintext[32];
+    unsigned char ciphertext1[40];
+    unsigned char ciphertext2[40];
+    size_t output_len, i;
+
+    memset( plaintext, 0, sizeof( plaintext ) );
+    memset( ciphertext1, 0, sizeof( ciphertext1 ) );
+    memset( ciphertext2, 0, sizeof( ciphertext2 ) );
+    memset( key, 0, sizeof( key ) );
+
+    /*
+     * 1. Check wrap and unwrap with two seperate contexts
+     */
+    mbedtls_nist_kw_init( &ctx1 );
+    mbedtls_nist_kw_init( &ctx2 );
+
+    TEST_ASSERT( mbedtls_nist_kw_setkey( &ctx1,
+                                         MBEDTLS_CIPHER_ID_AES,
+                                         key, sizeof( key ) * 8,
+                                         1 ) == 0 );
+
+    TEST_ASSERT( mbedtls_nist_kw_wrap( &ctx1, MBEDTLS_KW_MODE_KW,
+                                       plaintext, sizeof( plaintext ),
+                                       ciphertext1, &output_len,
+                                       sizeof( ciphertext1 ) ) == 0 );
+    TEST_ASSERT( output_len == sizeof( ciphertext1 ) );
+
+    TEST_ASSERT( mbedtls_nist_kw_setkey( &ctx2,
+                                         MBEDTLS_CIPHER_ID_AES,
+                                         key, sizeof( key ) * 8,
+                                         0 ) == 0 );
+
+    TEST_ASSERT( mbedtls_nist_kw_unwrap( &ctx2, MBEDTLS_KW_MODE_KW,
+                                         ciphertext1, output_len,
+                                         plaintext, &output_len,
+                                         sizeof( plaintext ) ) == 0 );
+
+    TEST_ASSERT( output_len == sizeof( plaintext ) );
+    for( i = 0; i < sizeof( plaintext ); i++ )
+    {
+        TEST_ASSERT( plaintext[i] == 0 );
+    }
+    mbedtls_nist_kw_free( &ctx1 );
+    mbedtls_nist_kw_free( &ctx2 );
+
+    /*
+     * 2. Check wrapping with two modes, on same context
+     */
+    mbedtls_nist_kw_init( &ctx1 );
+    mbedtls_nist_kw_init( &ctx2 );
+    output_len = sizeof( ciphertext1 );
+
+    TEST_ASSERT( mbedtls_nist_kw_setkey( &ctx1,
+                                         MBEDTLS_CIPHER_ID_AES,
+                                         key, sizeof( key ) * 8,
+                                         1 ) == 0 );
+
+    TEST_ASSERT( mbedtls_nist_kw_wrap( &ctx1, MBEDTLS_KW_MODE_KW,
+                                       plaintext, sizeof( plaintext ),
+                                       ciphertext1, &output_len,
+                                       sizeof( ciphertext1 ) ) == 0 );
+    TEST_ASSERT( output_len == sizeof( ciphertext1 ) );
+
+    TEST_ASSERT( mbedtls_nist_kw_wrap( &ctx1, MBEDTLS_KW_MODE_KWP,
+                                       plaintext, sizeof( plaintext ),
+                                       ciphertext2, &output_len,
+                                       sizeof( ciphertext2 ) ) == 0 );
+
+    TEST_ASSERT( output_len == sizeof( ciphertext2 ) );
+
+    TEST_ASSERT( mbedtls_nist_kw_setkey( &ctx2,
+                                         MBEDTLS_CIPHER_ID_AES,
+                                         key, sizeof( key ) * 8,
+                                         0 ) == 0 );
+
+    TEST_ASSERT( mbedtls_nist_kw_unwrap( &ctx2, MBEDTLS_KW_MODE_KW,
+                                         ciphertext1, sizeof( ciphertext1 ),
+                                         plaintext, &output_len,
+                                         sizeof( plaintext ) ) == 0 );
+
+    TEST_ASSERT( output_len == sizeof( plaintext ) );
+
+    for( i = 0; i < sizeof( plaintext ); i++ )
+    {
+        TEST_ASSERT( plaintext[i] == 0 );
+    }
+
+    TEST_ASSERT( mbedtls_nist_kw_unwrap( &ctx2, MBEDTLS_KW_MODE_KWP,
+                                         ciphertext2, sizeof( ciphertext2 ),
+                                         plaintext, &output_len,
+                                         sizeof( plaintext ) ) == 0 );
+
+    TEST_ASSERT( output_len == sizeof( plaintext ) );
+
+    for( i = 0; i < sizeof( plaintext ); i++ )
+    {
+        TEST_ASSERT( plaintext[i] == 0 );
+    }
+
+exit:
+    mbedtls_nist_kw_free( &ctx1 );
+    mbedtls_nist_kw_free( &ctx2 );
+}
+/* END_CASE */
+
+/* BEGIN_CASE */
+void mbedtls_nist_kw_setkey( int cipher_id, int key_size,
+                             int is_wrap, int result )
+{
+    mbedtls_nist_kw_context ctx;
+    unsigned char key[32];
+    int ret;
+
+    mbedtls_nist_kw_init( &ctx );
+
+    memset( key, 0x2A, sizeof( key ) );
+    TEST_ASSERT( (unsigned) key_size <= 8 * sizeof( key ) );
+
+    ret = mbedtls_nist_kw_setkey( &ctx, cipher_id, key, key_size, is_wrap );
+    TEST_ASSERT( ret == result );
+
+exit:
+    mbedtls_nist_kw_free( &ctx );
+}
+/* END_CASE */
+
+/* BEGIN_CASE depends_on:MBEDTLS_AES_C */
+void nist_kw_plaintext_lengths( int in_len, int out_len, int mode, int res )
+{
+    mbedtls_nist_kw_context ctx;
+    unsigned char key[16];
+    unsigned char *plaintext = NULL;
+    unsigned char *ciphertext = NULL;
+    size_t output_len = out_len;
+
+    mbedtls_nist_kw_init( &ctx );
+
+    memset( key, 0, sizeof( key ) );
+
+    if (in_len == 0)
+    {
+        /* mbedtls_calloc can return NULL for zero-length buffers. Make sure we
+         * always have a plaintext buffer, even if the length is 0. */
+        plaintext = mbedtls_calloc( 1, 1 );
+    }
+    else
+    {
+        plaintext = mbedtls_calloc( 1, in_len );
+    }
+    TEST_ASSERT( plaintext != NULL );
+    ciphertext = mbedtls_calloc( 1, output_len );
+    TEST_ASSERT( ciphertext != NULL );
+
+    memset( plaintext, 0, in_len );
+    memset( ciphertext, 0, output_len );
+
+
+    TEST_ASSERT( mbedtls_nist_kw_setkey( &ctx, MBEDTLS_CIPHER_ID_AES,
+                                         key, 8 * sizeof( key ), 1 ) == 0 );
+
+    TEST_ASSERT( mbedtls_nist_kw_wrap( &ctx, mode, plaintext, in_len,
+                                      ciphertext, &output_len,
+                                      output_len ) == res );
+    if( res == 0 )
+    {
+        if( mode == MBEDTLS_KW_MODE_KWP )
+            TEST_ASSERT( output_len == (size_t) in_len + 8 -
+                         ( in_len % 8 ) + 8 );
+        else
+            TEST_ASSERT( output_len == (size_t) in_len + 8 );
+    }
+    else
+    {
+        TEST_ASSERT( output_len == 0 );
+    }
+
+exit:
+    mbedtls_free( ciphertext );
+    mbedtls_free( plaintext );
+    mbedtls_nist_kw_free( &ctx );
+}
+/* END_CASE */
+
+/* BEGIN_CASE depends_on:MBEDTLS_AES_C */
+void nist_kw_ciphertext_lengths( int in_len, int out_len, int mode, int res )
+{
+    mbedtls_nist_kw_context ctx;
+    unsigned char key[16];
+    unsigned char *plaintext = NULL;
+    unsigned char *ciphertext = NULL;
+    int unwrap_ret;
+    size_t output_len = out_len;
+
+    mbedtls_nist_kw_init( &ctx );
+
+    memset( key, 0, sizeof( key ) );
+
+    plaintext = mbedtls_calloc( 1, output_len );
+    TEST_ASSERT( plaintext != NULL );
+    ciphertext = mbedtls_calloc( 1, in_len );
+    TEST_ASSERT( ciphertext != NULL );
+
+    memset( plaintext, 0, output_len );
+    memset( ciphertext, 0, in_len );
+
+
+    TEST_ASSERT( mbedtls_nist_kw_setkey( &ctx, MBEDTLS_CIPHER_ID_AES,
+                                         key, 8 * sizeof( key ), 0 ) == 0 );
+    unwrap_ret = mbedtls_nist_kw_unwrap( &ctx, mode, ciphertext, in_len,
+                                         plaintext, &output_len,
+                                         output_len );
+
+    if( res == 0 )
+        TEST_ASSERT( unwrap_ret == MBEDTLS_ERR_CIPHER_AUTH_FAILED );
+    else
+        TEST_ASSERT( unwrap_ret == res );
+
+    TEST_ASSERT( output_len == 0 );
+
+exit:
+    mbedtls_free( ciphertext );
+    mbedtls_free( plaintext );
+    mbedtls_nist_kw_free( &ctx );
+}
+/* END_CASE */
+
+/* BEGIN_CASE */
+void mbedtls_nist_kw_wrap( int cipher_id, int mode,
+                           char *key_hex, char *msg_hex,
+                           char *result_hex )
+{
+    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, output_len, 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 = unhexify( key, key_hex );
+    msg_len = unhexify( msg, msg_hex );
+    result_len = unhexify( expected_result, result_hex );
+    output_len = sizeof( result );
+
+    TEST_ASSERT( mbedtls_nist_kw_setkey( &ctx, cipher_id, key, key_len * 8, 1 )
+                 == 0 );
+
+    /* Test with input == output */
+    TEST_ASSERT( mbedtls_nist_kw_wrap( &ctx, mode, msg, msg_len,
+                 result, &output_len, sizeof( result ) ) == 0 );
+
+    TEST_ASSERT( output_len == result_len );
+
+    TEST_ASSERT( memcmp( expected_result, result, result_len ) == 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++ )
+    {
+        TEST_ASSERT( result[i] == '+' );
+    }
+
+exit:
+    mbedtls_nist_kw_free( &ctx );
+}
+/* END_CASE */
+
+/* BEGIN_CASE */
+void mbedtls_nist_kw_unwrap( int cipher_id, int mode,
+                             char *key_hex, char *msg_hex,
+                             char *result_hex, 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, output_len, 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 = unhexify( key, key_hex );
+    msg_len = unhexify( msg, msg_hex );
+    result_len = unhexify( expected_result, result_hex );
+    output_len = sizeof( result );
+
+    TEST_ASSERT( mbedtls_nist_kw_setkey( &ctx, cipher_id, key, key_len * 8, 0 )
+                 == 0 );
+
+    /* Test with input == output */
+    TEST_ASSERT( mbedtls_nist_kw_unwrap( &ctx, mode, msg, msg_len,
+                 result, &output_len, sizeof( result ) ) == expected_ret );
+    if( expected_ret == 0 )
+    {
+        TEST_ASSERT( output_len == result_len );
+        TEST_ASSERT( memcmp( expected_result, result, result_len ) == 0 );
+    }
+    else
+    {
+        TEST_ASSERT( output_len == 0 );
+    }
+
+    /* Check that the function didn't write beyond the end of the buffer. */
+    for( i = msg_len - 8; i < sizeof( result ); i++ )
+    {
+        TEST_ASSERT( result[i] == '+' );
+    }
+
+exit:
+    mbedtls_nist_kw_free( &ctx );
+}
+/* END_CASE */