chacha20: fix bug in starts() and add test for it
Previously the streaming API would fail when encrypting multiple messages with
the same key.
diff --git a/tests/suites/test_suite_chacha20.function b/tests/suites/test_suite_chacha20.function
index 9c0b985..fb3ad3e 100644
--- a/tests/suites/test_suite_chacha20.function
+++ b/tests/suites/test_suite_chacha20.function
@@ -23,6 +23,7 @@
size_t nonce_len;
size_t src_len;
size_t dst_len;
+ mbedtls_chacha20_context ctx;
memset( key_str, 0x00, sizeof( key_str ) );
memset( nonce_str, 0x00, sizeof( nonce_str ) );
@@ -39,11 +40,45 @@
TEST_ASSERT( key_len == 32U );
TEST_ASSERT( nonce_len == 12U );
+ /*
+ * Test the integrated API
+ */
TEST_ASSERT( mbedtls_chacha20_crypt( key_str, nonce_str, counter, src_len, src_str, output ) == 0 );
hexify( dst_str, output, src_len );
+ TEST_ASSERT( strcmp( (char*) dst_str, hex_dst_string ) == 0 );
- TEST_ASSERT( strcmp( (char*) dst_str, hex_dst_string ) == 0);
+ /*
+ * Test the streaming API
+ */
+ mbedtls_chacha20_init( &ctx );
+
+ TEST_ASSERT( mbedtls_chacha20_setkey( &ctx, key_str ) == 0 );
+
+ TEST_ASSERT( mbedtls_chacha20_starts( &ctx, nonce_str, counter ) == 0 );
+
+ memset( output, 0x00, sizeof( output ) );
+ TEST_ASSERT( mbedtls_chacha20_update( &ctx, src_len, src_str, output ) == 0 );
+
+ hexify( dst_str, output, src_len );
+ TEST_ASSERT( strcmp( (char*) dst_str, hex_dst_string ) == 0 );
+
+ /*
+ * Test the streaming API again, piecewise
+ */
+
+ /* Don't reset the context of key, in order to test that starts() do the
+ * right thing. */
+ TEST_ASSERT( mbedtls_chacha20_starts( &ctx, nonce_str, counter ) == 0 );
+
+ memset( output, 0x00, sizeof( output ) );
+ TEST_ASSERT( mbedtls_chacha20_update( &ctx, 1, src_str, output ) == 0 );
+ TEST_ASSERT( mbedtls_chacha20_update( &ctx, src_len - 1, src_str + 1, output + 1 ) == 0 );
+
+ hexify( dst_str, output, src_len );
+ TEST_ASSERT( strcmp( (char*) dst_str, hex_dst_string ) == 0 );
+
+ mbedtls_chacha20_free( &ctx );
}
/* END_CASE */