Use the getrandom() syscall on systems that support it.

frontend/MCrypt.rc

@@ -0,0 +1,55 @@
+/////////////////////////////////////////////////////////////////////////////
+//
+// Microsoft Visual C++ generated resource script.
+//
+#define APSTUDIO_READONLY_SYMBOLS
+#include "WinResrc.h" //"afxres.h"
+#undef APSTUDIO_READONLY_SYMBOLS
+
+/////////////////////////////////////////////////////////////////////////////
+//
+// Neutral resources
+//
+#ifdef _WIN32
+LANGUAGE LANG_NEUTRAL, SUBLANG_NEUTRAL
+#pragma code_page(1252)
+#endif //_WIN32
+
+/////////////////////////////////////////////////////////////////////////////
+//
+// Version
+//
+VS_VERSION_INFO VERSIONINFO
+ FILEVERSION    1,0,0,0
+ PRODUCTVERSION 1,0,0,0
+ FILEFLAGSMASK 0x17L
+#ifdef _DEBUG
+ FILEFLAGS 0x3L
+#else
+ FILEFLAGS 0x2L
+#endif
+ FILEOS 0x40004L
+ FILETYPE 0x1L
+ FILESUBTYPE 0x0L
+BEGIN
+    BLOCK "StringFileInfo"
+    BEGIN
+        BLOCK "000004b0"
+        BEGIN
+            VALUE "ProductName", "MCrypt"
+            VALUE "FileDescription", "MCrypt Utility"
+            VALUE "ProductVersion", "1.0.0"
+            VALUE "FileVersion", "1.0.0"
+            VALUE "InternalName", "mcrypt"
+            VALUE "OriginalFilename", "mcrypt.exe"
+            VALUE "LegalCopyright", "Created by LoRd_MuldeR <MuldeR2@GMX.de>"
+            VALUE "CompanyName", "Muldersoft"
+            VALUE "LegalTrademarks", "Muldersoft"
+            VALUE "Comments", "This work has been released under the CC0 1.0 Universal license!"
+        END
+    END
+    BLOCK "VarFileInfo"
+    BEGIN
+        VALUE "Translation", 0x0, 1200
+    END
+END

frontend/MCrypt.vcxproj

@@ -33,12 +33,15 @@
     <ClInclude Include="src\platform.h" />
     <ClInclude Include="src\utils.h" />
   </ItemGroup>
+  <ItemGroup>
+    <ResourceCompile Include="MCrypt.rc" />
+  </ItemGroup>
   <PropertyGroup Label="Globals">
     <VCProjectVersion>16.0</VCProjectVersion>
     <Keyword>Win32Proj</Keyword>
     <ProjectGuid>{86d28793-713e-4cec-9686-335514ac5ef0}</ProjectGuid>
     <RootNamespace>MCrypt</RootNamespace>
-    <WindowsTargetPlatformVersion>10.0</WindowsTargetPlatformVersion>
+    <WindowsTargetPlatformVersion>7.0</WindowsTargetPlatformVersion>
   </PropertyGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.Default.props" />
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'" Label="Configuration">
@@ -89,21 +92,25 @@
     <LinkIncremental>true</LinkIncremental>
     <OutDir>$(SolutionDir)bin\$(Platform)\$(Configuration)\</OutDir>
     <IntDir>$(SolutionDir)obj\$(Platform)\$(Configuration)\$(ProjectName)\</IntDir>
+    <TargetName>mcrypt</TargetName>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <OutDir>$(SolutionDir)bin\$(Platform)\$(Configuration)\</OutDir>
     <IntDir>$(SolutionDir)obj\$(Platform)\$(Configuration)\$(ProjectName)\</IntDir>
+    <TargetName>mcrypt</TargetName>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">
     <LinkIncremental>true</LinkIncremental>
     <OutDir>$(SolutionDir)bin\$(Platform)\$(Configuration)\</OutDir>
     <IntDir>$(SolutionDir)obj\$(Platform)\$(Configuration)\$(ProjectName)\</IntDir>
+    <TargetName>mcrypt</TargetName>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|x64'">
     <LinkIncremental>false</LinkIncremental>
     <OutDir>$(SolutionDir)bin\$(Platform)\$(Configuration)\</OutDir>
     <IntDir>$(SolutionDir)obj\$(Platform)\$(Configuration)\$(ProjectName)\</IntDir>
+    <TargetName>mcrypt</TargetName>
   </PropertyGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <ClCompile>
@@ -140,7 +147,8 @@
       <SubSystem>Console</SubSystem>
       <EnableCOMDATFolding>true</EnableCOMDATFolding>
       <OptimizeReferences>true</OptimizeReferences>
-      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <GenerateDebugInformation>false</GenerateDebugInformation>
+      <LinkTimeCodeGeneration>UseLinkTimeCodeGeneration</LinkTimeCodeGeneration>
     </Link>
   </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">
@@ -177,7 +185,8 @@
       <SubSystem>Console</SubSystem>
       <EnableCOMDATFolding>true</EnableCOMDATFolding>
       <OptimizeReferences>true</OptimizeReferences>
-      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <GenerateDebugInformation>false</GenerateDebugInformation>
+      <LinkTimeCodeGeneration>UseLinkTimeCodeGeneration</LinkTimeCodeGeneration>
     </Link>
   </ItemDefinitionGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />

frontend/MCrypt.vcxproj.filters

@@ -36,4 +36,9 @@
       <Filter>Header Files</Filter>
     </ClInclude>
   </ItemGroup>
+  <ItemGroup>
+    <ResourceCompile Include="MCrypt.rc">
+      <Filter>Resource Files</Filter>
+    </ResourceCompile>
+  </ItemGroup>
 </Project>

frontend/src/main.c

@@ -11,6 +11,7 @@
 #include <string.h>
 #include <time.h>
 #include <inttypes.h>
+#include <ctype.h>
 
 static void print_string(const char *const text, const size_t length)
 {
@@ -42,16 +43,34 @@ static int open_files(FILE** const fin, FILE** const fout, const CHR* const inpu
 	return 0;
 }
 
+static int weak_passphrase(const CHR *str)
+{
+	int flags[4U] = { 0, 0, 0, 0 };
+	while (*str)
+	{
+		const CHR c = *str++;
+		if      (iswupper(c)) flags[0U] = 1;
+		else if (iswlower(c)) flags[1U] = 1;
+		else if (iswdigit(c)) flags[2U] = 1;
+		else if (iswgraph(c)) flags[3U] = 1;
+	}
+	const int strong = flags[0U] && flags[1U] && flags[2U] && flags[3U];
+	return !strong;
+}
+
 static int encrypt(const CHR* const passphrase, const CHR* const input, const CHR* const output)
 {
 	mcrypt_t ctx = NULL;
 	FILE *fin = NULL, *fout = NULL;
 	int result = -1;
 
-	if (!passphrase[0U])
+	if (STRLEN(passphrase) < 8U)
 	{
-		FPUTS(T("Error: The given passphrase is empty!\n\n"), stderr);
+		FPUTS(L"Warning: Using a short passphrase. Eight characters or more are recommended!\n\n", stderr);
-		goto clean_up;
+	}
+	else if (weak_passphrase(passphrase))
+	{
+		FPUTS(L"Warning: Using a weak passphrase. A mix of upper-case characters, lower-case characters, digits and 'special' characters is recommended!\n\n", stderr);
 	}
 
 	char *const passphrase_utf8 = utf16_to_bytes(passphrase, CP_UTF8);
@@ -188,12 +207,6 @@ static int decrypt(const CHR* const passphrase, const CHR* const input, const CH
 	FILE *fin = NULL, *fout = NULL;
 	int result = -1;
 
-	if (!passphrase[0U])
-	{
-		FPUTS(T("Error: The given passphrase is empty!\n\n"), stderr);
-		goto clean_up;
-	}
-
 	char *const passphrase_utf8 = utf16_to_bytes(passphrase, CP_UTF8);
 	if (!passphrase_utf8)
 	{
@@ -329,32 +342,50 @@ clean_up:
 
 int MAIN(int argc, CHR* argv[])
 {
-	FPRINTF(stderr, T("MCrypt Utility [%") T(PRIstr) T("]\n"), __DATE__" "__TIME__);
+	FPRINTF(stderr, T("MCrypt Utility [%") T(PRIstr) T("]\n"), __DATE__", "__TIME__);
 	FPRINTF(stderr, T("Powered by libMCrypt v%") T(PRIstr) T(" [%") T(PRIstr) T("]\n\n"), LIBMCRYPT_VERSION, LIBMCRYPT_BUILDNO);
 
-	if (argc < 4)
+	if ((argc < 5) || (!STRICMP(argv[1U], T("--help"))) || (!STRICMP(argv[1U], T("--version"))))
 	{
+		FPUTS(T("This software has been released under the CC0 1.0 Universal license:\n"), stderr);
+		FPUTS(T("https://creativecommons.org/publicdomain/zero/1.0/legalcode\n\n"), stderr);
+		if (argc < 2)
+		{
+			FPUTS(T("Nothing to do!\n\n"), stderr);
+		}
 		FPUTS(T("Usage:\n"), stderr);
-		FPRINTF(stderr, T("  %s [--decrypt] <passphrase> <input> <output>\n\n"), argv[0U]);
+		FPRINTF(stderr, T("  %") T(PRIwcs) T(" --encrypt <passphrase> <input.txt> <output.enc>\n"),   argv[0U]);
+		FPRINTF(stderr, T("  %") T(PRIwcs) T(" --decrypt <passphrase> <input.enc> <output.txt>\n\n"), argv[0U]);
 		return 1;
 	}
 
-	int result = -1;
+	if (!argv[1U][0U])
-	const clock_t clk_start = clock();
+	{
+		FPUTS(T("Error: The passphrase must not be empty!\n\n"), stderr);
+		return 1;
+	}
 
-	if ((argc > 4) && ((!STRICMP(argv[1U], T("-d"))) || (!STRICMP(argv[1U], T("--decrypt")))))
+	const clock_t clk_start = clock();
+	int result = -1;
+
+	if (!STRICMP(argv[1U], T("--encrypt")))
+	{
+		result = encrypt(argv[2U], argv[3U], argv[4U]);
+	}
+	else if (!STRICMP(argv[1U], T("--decrypt")))
 	{
 		result = decrypt(argv[2U], argv[3U], argv[4U]);
-		erase(argv[2U], STRLEN(argv[2U]) * sizeof(CHR));
 	}
 	else
 	{
-		result = encrypt(argv[1U], argv[2U], argv[3U]);
+		FPRINTF(stderr, T("Error: Command \"%") T(PRIwcs) T("\" is unknown!\n\n"), argv[1U]);
-		erase(argv[1U], STRLEN(argv[1U]) * sizeof(CHR));
+		erase(argv[2U], STRLEN(argv[2U]) * sizeof(CHR));
+		return 1;
 	}
 
 	FPUTS(T("--------\n\n"), stderr);
 	fflush(stderr);
+	erase(argv[2U], STRLEN(argv[2U]) * sizeof(CHR));
 
 	const clock_t clk_end = clock();
 	FPRINTF(stderr, T("Operation completed after %.1f seconds.\n\n"), (clk_end - clk_start) / ((double)CLOCKS_PER_SEC));

frontend/src/platform.h

@@ -20,8 +20,10 @@
 #define STAT64_T struct _stati64
 #ifdef __MINGW32__
 #define PRIstr "hs"
+#define PRIwcs "ls"
 #else
 #define PRIstr "S"
+#define PRIwcs "s"
 #endif
 #else
 #define MAIN main
@@ -36,6 +38,7 @@
 #define FSTAT64(X,Y) fstat64((X),(Y))
 #define STAT64_T struct stat64
 #define PRIstr "s"
+#define PRIwcs "ls"
 #endif
 
 #define T(X) _T(X)

libMCrypt/libMCrypt.vcxproj

@@ -31,7 +31,7 @@
     <Keyword>Win32Proj</Keyword>
     <ProjectGuid>{a4a3879c-bd2c-4304-af66-7349cef7e4c0}</ProjectGuid>
     <RootNamespace>libMCrypt</RootNamespace>
-    <WindowsTargetPlatformVersion>10.0</WindowsTargetPlatformVersion>
+    <WindowsTargetPlatformVersion>7.0</WindowsTargetPlatformVersion>
   </PropertyGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.Default.props" />
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'" Label="Configuration">
@@ -82,21 +82,25 @@
     <LinkIncremental>true</LinkIncremental>
     <OutDir>$(SolutionDir)bin\$(Platform)\$(Configuration)\</OutDir>
     <IntDir>$(SolutionDir)obj\$(Platform)\$(Configuration)\$(ProjectName)\</IntDir>
+    <TargetName>libmcrypt-1</TargetName>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <OutDir>$(SolutionDir)bin\$(Platform)\$(Configuration)\</OutDir>
     <IntDir>$(SolutionDir)obj\$(Platform)\$(Configuration)\$(ProjectName)\</IntDir>
+    <TargetName>libmcrypt-1</TargetName>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">
     <LinkIncremental>true</LinkIncremental>
     <OutDir>$(SolutionDir)bin\$(Platform)\$(Configuration)\</OutDir>
     <IntDir>$(SolutionDir)obj\$(Platform)\$(Configuration)\$(ProjectName)\</IntDir>
+    <TargetName>libmcrypt-1</TargetName>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|x64'">
     <LinkIncremental>false</LinkIncremental>
     <OutDir>$(SolutionDir)bin\$(Platform)\$(Configuration)\</OutDir>
     <IntDir>$(SolutionDir)obj\$(Platform)\$(Configuration)\$(ProjectName)\</IntDir>
+    <TargetName>libmcrypt-1</TargetName>
   </PropertyGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <ClCompile>

libMCrypt/src/mcrypt.c

@@ -12,7 +12,7 @@
 #include <string.h>
 
 const char* const LIBMCRYPT_VERSION = "1.0.0";
-const char* const LIBMCRYPT_BUILDNO = __DATE__" "__TIME__;
+const char* const LIBMCRYPT_BUILDNO = __DATE__", "__TIME__;
 
 typedef struct
 {

libMCrypt/src/utils.c

@@ -12,6 +12,12 @@
 #ifdef __unix__
 #include <unistd.h>
 #include <fcntl.h>
+#if (defined(__GLIBC__) && defined(__GLIBC_MINOR__) && (__GLIBC__ >= 2) && (__GLIBC_MINOR__ >= 25)) || (defined(__FreeBSD__) && (__FreeBSD__ >= 12))
+#define HAVE_GENRANDOM_SYSCALL 1
+#include <sys/random.h>
+#else
+#undef HAVE_GENRANDOM_SYSCALL
+#endif
 #endif
 
 int mcrypt_random_bytes(uint8_t* const buffer, const size_t length)
@@ -36,9 +42,16 @@ int mcrypt_random_bytes(uint8_t* const buffer, const size_t length)
 	return 0;
 #else
 #ifdef __unix__
-	static const char* const PATH[] = { "/dev/urandom", "/dev/random" };
+#ifdef HAVE_GENRANDOM_SYSCALL
+	if (getrandom(buffer, length, 0U) >= length)
+	{
+		return 0;
+	}
+	return -1;
+#else
+	static const char* const PATH[] = { "/dev/urandom", "/dev/arandom", "/dev/random" };
 	int result = -1;
-	for (size_t i = 0; (i < 2U) && (result < 0); ++i)
+	for (size_t i = 0; (i < 3U) && (result < 0); ++i)
 	{
 		const int fd = open(PATH[i], O_RDONLY);
 		if (fd >= 0)
@@ -51,6 +64,7 @@ int mcrypt_random_bytes(uint8_t* const buffer, const size_t length)
 		}
 	}
 	return result;
+#endif
 #else
 #error Unsupported target platform!
 #endif