Adding testing support (#3)

* adding a testing "framework", a few tests and fixing some minor bugs

* addressing easy PR comments, adding a .editorconfig to help maintain a consistent coding style, changing the tests indetation to tabs.

* preventing the compiler to optimize cc_clear

* fixing typo

Co-authored-by: Andrew Hyatt <ahyattdev@icloud.com>

.editorconfig

@@ -0,0 +1,9 @@
+[*]
+end_of_line = lf
+insert_final_newline = true
+
+[*.{c,h}]
+indent_style = tab
+
+[CMakeLists.txt]
+indent_style = tab

.gitignore

@@ -0,0 +1,2 @@
+/build
+/.idea/

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "external/ctest"]
+	path = external/ctest
+	url = git@github.com:farmisen/ctest.git

CMakeLists.txt

@@ -1,10 +1,41 @@
-project(darling-corecrypto)
+project(darling-corecrypto C)
 
-add_compile_options(
-	-nostdinc
-	-Wno-return-type
-	-Werror
-)
+# User option to turn the corecrypto specific tests
+option(CORECRYPTO_ENABLE_TESTS
+	"Enable the compilation and running of corecrypto's unit tests" OFF)
+
+# Test are built only if BUILD_TESTING && CORECRYPTO_ENABLE_TESTS are set to ON
+include(CTest)
+if (BUILD_TESTING AND CORECRYPTO_ENABLE_TESTS)
+	set(BUILD_CORECRYPTO_TESTS ON)
+else (BUILD_TESTING AND CORECRYPTO_ENABLE_TESTS)
+	set(BUILD_CORECRYPTO_TESTS OFF)
+endif (BUILD_TESTING AND CORECRYPTO_ENABLE_TESTS)
+
+# Set endianess for test builds
+if (BUILD_CORECRYPTO_TESTS)
+	include (TestBigEndian)
+	TEST_BIG_ENDIAN(IS_BIG_ENDIAN)
+	if(IS_BIG_ENDIAN)
+		add_definitions(-D__BIG_ENDIAN__=1)
+	else(IS_BIG_ENDIAN)
+		add_definitions(-D__LITTLE_ENDIAN__=1)
+	endif(IS_BIG_ENDIAN)
+endif (BUILD_CORECRYPTO_TESTS)
+
+# Set env dependent compile options
+if (NOT BUILD_CORECRYPTO_TESTS)
+	add_compile_options(
+		-nostdinc
+		-Wno-return-type
+    -Werror
+	)
+else (NOT BUILD_CORECRYPTO_TESTS)
+	add_compile_options(
+		-Wno-return-type
+    -Werror
+	)
+endif (NOT BUILD_CORECRYPTO_TESTS)
 
 add_definitions(
 	-DDEBUG
@@ -15,9 +46,8 @@ include_directories(
 	${CMAKE_CURRENT_SOURCE_DIR}/include
 )
 
-set(DYLIB_INSTALL_NAME "/usr/lib/system/libcorecrypto.dylib")
-add_circular(corecrypto FAT
-	SOURCES
+
+set(corecrypto_sources
 		src/cc.c
 		src/ccdigest.c
 		src/ccmd2.c
@@ -55,19 +85,40 @@ add_circular(corecrypto FAT
 		src/ccansikdf.c
 		src/ccecies.c
 		src/ccrng_pbkdf2.c
-
-	SIBLINGS
-		system_dyld
-		compiler_rt
-		system_kernel
-		platform
-		system_malloc
-		system_c
-		system_blocks
-		system_pthread
-		macho
-		libdispatch_shared
 )
-make_fat(corecrypto)
 
-install(TARGETS corecrypto DESTINATION libexec/darling/usr/lib/system)
+if (NOT BUILD_CORECRYPTO_TESTS)
+	set(DYLIB_INSTALL_NAME "/usr/lib/system/libcorecrypto.dylib")
+	add_circular(corecrypto FAT
+		SOURCES
+			${corecrypto_sources}
+		SIBLINGS
+			system_dyld
+			compiler_rt
+			system_kernel
+			platform
+			system_malloc
+			system_c
+			system_blocks
+			system_pthread
+			macho
+			libdispatch_shared
+	)
+	make_fat(corecrypto)
+else (NOT BUILD_CORECRYPTO_TESTS)
+	add_library(corecrypto
+		SHARED
+			${corecrypto_sources}
+	)
+endif (NOT BUILD_CORECRYPTO_TESTS)
+
+if (NOT BUILD_CORECRYPTO_TESTS)
+	install(TARGETS corecrypto DESTINATION libexec/darling/usr/lib/system)
+else (NOT BUILD_CORECRYPTO_TESTS)
+	enable_testing()
+	include_directories(
+		${CMAKE_CURRENT_SOURCE_DIR}/tests/include
+	)
+	add_subdirectory(external/ctest)
+	add_subdirectory(tests)
+endif (NOT BUILD_CORECRYPTO_TESTS)

README.md

@@ -0,0 +1,24 @@
+# Darling-CoreCrypto
+
+Rewrite of Apple CoreCrypto for the Darling project.
+
+## Testing
+
+Setting the CORECRYPTO_ENABLE_TESTS CMake option to ON as shown below will build CoreCrypto and the test suite
+ for your native host instead of Darling. It has only been tested on Ubuntu 18.04 and OSX 10.14.
+
+```
+$ mkdir build
+$ cd build
+$ cmake -DCORECRYPTO_ENABLE_TESTS=ON ..
+$ make
+$ ./tests/test_corecrypto
+```
+
+### Continuous testing
+
+The following command will watch for a any change in the CoreCrypto lib, CMake files or tests and will rebuild and run the test suite.
+
+```
+$ ./tests/watch.sh
+```

external/ctest

@@ -0,0 +1 @@
+Subproject commit 632ec756145658f060cc812b13860b0f490815e9

include/corecrypto/ccasn1.h

@@ -88,7 +88,7 @@ size_t ccoid_size(ccoid_t oid) {
     return 2 + CCOID(oid)[1];
 }
 
-CC_INLINE CC_PURE CC_NONNULL((1)) CC_NONNULL((2))
+CC_INLINE CC_PURE CC_NONNULL_TU((1)) CC_NONNULL_TU((2))
 bool ccoid_equal(ccoid_t oid1, ccoid_t oid2) {
     return  (ccoid_size(oid1) == ccoid_size(oid2)
             && memcmp(CCOID(oid1), CCOID(oid2), ccoid_size(oid1))== 0);

src/cc.c

@@ -33,7 +33,10 @@ struct ccrng_state * ccDRBGGetRngState(int *error) {
 
 void cc_clear(size_t len, void *dst)
 {
-	memset(dst, 0, len);
+	volatile unsigned char *ptr = (volatile unsigned char*) dst;
+	while (len--) {
+		*ptr++ = 0;
+	}
 }
 
 /* https://cryptocoding.net/index.php/Coding_rules#Avoid_branchings_controlled_by_secret_data */
@@ -41,13 +44,16 @@ void* cc_muxp(int s, const void *a, const void *b)
 {
 	uintptr_t mask = -(s != 0);
 	uintptr_t ret = mask & (((uintptr_t)a) ^ ((uintptr_t)b));
-	ret = ret ^ ((uintptr_t)a);
+	ret = ret ^ ((uintptr_t)b);
 	return (void*) ret;
 }
 
 /* https://cryptocoding.net/index.php/Coding_rules#Compare_secret_strings_in_constant_time */
 int cc_cmp_safe(size_t size, const void* a, const void* b)
 {
+	if ( size == 0) {
+		return 1;
+	}
 	const unsigned char *_a = (const unsigned char *) a;
 	const unsigned char *_b = (const unsigned char *) b;
 	unsigned char result = 0;
@@ -55,9 +61,9 @@ int cc_cmp_safe(size_t size, const void* a, const void* b)
 
 	for (i = 0; i < size; i++)
 	{
-		result |= _a[i] ^ _b[i];
+		result |=  (unsigned) _a[i] ^ _b[i];
 	}
 
-	return result;
+	return result ? 1 : 0;
 }
 

tests/CMakeLists.txt

@@ -0,0 +1,11 @@
+set(TEST_SOURCES
+	main.c
+	cc_tests.c
+	cc_priv_tests.c
+)
+
+add_executable(test_corecrypto ${TEST_SOURCES})
+
+target_link_libraries(test_corecrypto ctest corecrypto)
+
+add_test(TestCorecrypto test_corecrypto)

tests/cc_priv_tests.c

@@ -0,0 +1,9 @@
+#include <ctest.h>
+#include "../include/corecrypto/cc_priv.h"
+
+CTEST(cc, cc_muxp) {
+	const unsigned char a;
+	const unsigned char b;
+	ASSERT_TRUE(&a == cc_muxp(1, (void *) &a, (void *) &b));
+	ASSERT_TRUE(&b == cc_muxp(0, (void *) &a, (void *) &b));
+}

tests/cc_tests.c

@@ -0,0 +1,99 @@
+#include <stdlib.h>
+#include <ctest.h>
+#include "../include/corecrypto/cc.h"
+
+enum { SIZE = 256 };
+
+CTEST(cc, cc_zero) {
+	unsigned char buffer[SIZE];
+	for(size_t i = 0 ; i < SIZE; ++i) {
+		buffer[i] = (unsigned char) i;
+	}
+	cc_zero(SIZE, buffer);
+	for (size_t i = 0; i < SIZE; ++i) {
+		ASSERT_EQUAL('\0', buffer[i]);
+	}
+}
+
+CTEST(cc, cc_clear) {
+	unsigned char buffer[SIZE];
+	for(size_t i = 0 ; i < SIZE; ++i) {
+		buffer[i] = (unsigned char) i;
+	}
+	cc_clear(SIZE, buffer);
+	for (size_t i = 0; i < SIZE; ++i) {
+		ASSERT_EQUAL('\0', buffer[i]);
+	}
+}
+
+CTEST(cc, cc_copy) {
+	unsigned char buffer1[SIZE];
+	unsigned char buffer2[SIZE];
+
+	for(size_t i = 0 ; i < SIZE; ++i) {
+		buffer1[i] = (unsigned char) rand();
+	}
+	cc_copy(SIZE, buffer2, buffer1);
+	for (size_t i = 0; i < SIZE; ++i) {
+		ASSERT_EQUAL(buffer1[i], buffer2[i]);
+	}
+}
+
+CTEST(cc, cc_xor) {
+	unsigned char buffer1[SIZE];
+	unsigned char buffer2[SIZE];
+	unsigned char buffer3[SIZE];
+
+	for(size_t i = 0 ; i < SIZE; ++i) {
+		buffer1[i] = (unsigned char) rand();
+		buffer2[i] = (unsigned char) rand();
+	}
+	cc_xor(SIZE, buffer3, buffer1, buffer2);
+	for (size_t i = 0; i < SIZE; ++i) {
+		ASSERT_EQUAL(buffer3[i], buffer1[i] ^ buffer2[i]);
+	}
+	cc_xor(SIZE, buffer3, buffer3, buffer2);
+	for (size_t i = 0; i < SIZE; ++i) {
+		ASSERT_EQUAL(buffer3[i], buffer1[i]);
+	}
+	cc_xor(SIZE, buffer3, buffer3, buffer3);
+	for (size_t i = 0; i < SIZE; ++i) {
+		ASSERT_EQUAL('\0', buffer3[i]);
+	}
+}
+
+CTEST(cc, cc_cmp_safe) {
+	unsigned char buffer1[SIZE];
+	unsigned char buffer2[SIZE];
+	for(size_t i = 0 ; i < SIZE; ++i) {
+		buffer1[i] = (unsigned char) rand();
+		buffer2[i] = (unsigned char) rand();
+	}
+
+	ASSERT_EQUAL(0, cc_cmp_safe(SIZE, buffer1, buffer1));
+	ASSERT_EQUAL(1,cc_cmp_safe(SIZE, buffer1, buffer2));
+	ASSERT_EQUAL(1,cc_cmp_safe(0, buffer1, buffer1));
+}
+
+CTEST(cc, CC_SWAP) {
+	unsigned  int a = 127;
+	unsigned  int b = 257;
+	CC_SWAP(a,b);
+	ASSERT_EQUAL(a, 257);
+	ASSERT_EQUAL(b, 127);
+	CC_SWAP(a,b);
+	ASSERT_EQUAL(a, 127);
+	ASSERT_EQUAL(b, 257);
+}
+
+CTEST(cc, CC_MAX) {
+	ASSERT_EQUAL(128, CC_MAX(63, 128));
+	ASSERT_EQUAL(-128, CC_MAX(-163, -128));
+	ASSERT_EQUAL(128, CC_MAX(128, -128));
+}
+
+CTEST(cc, CC_MIN) {
+	ASSERT_EQUAL(63, CC_MIN(63, 128));
+	ASSERT_EQUAL(-163, CC_MIN(-163, -128));
+	ASSERT_EQUAL(-128, CC_MIN(128, -128));
+}

tests/include/libkern/OSByteOrder.h

@@ -0,0 +1,12 @@
+#if defined(__APPLE__)
+	#include <libkern/OSByteOrder.h>
+#else
+	#ifndef _OS_BYTE_ORDER_H
+	#define _OS_BYTE_ORDER_H 1
+	#include <byteswap.h>
+
+	#define OSSwapInt32(x) __bswap_32(x)
+	#define _OSSwapInt64 __bswap_64
+
+	#endif // _OS_BYTE_ORDER_H
+#endif // defined(__APPLE__)

tests/main.c

@@ -0,0 +1,12 @@
+#define CTEST_MAIN
+
+// uncomment lines below to enable/disable features. See README.md for details
+#define CTEST_SEGFAULT
+//#define CTEST_NO_COLORS
+#define CTEST_COLOR_OK
+
+#include <ctest.h>
+
+int main(int argc, const char *argv[]) {
+	return ctest_main(argc, argv);
+}