Make hardened builds by default because we can.

Properly convert label to CP850.

Author: profi200

Makefile

@@ -5,20 +5,20 @@ TARGET   := $(notdir $(CURDIR))
 BUILD    := build
 INCLUDES := include
 SOURCES  := source
-DEFINES  :=
+DEFINES  := -D_FORTIFY_SOURCE=2
 
 
 # Compiler settings
 ARCH     :=
-CFLAGS   := $(ARCH) -std=c17 -O2 -g -fstrict-aliasing \
-			-ffunction-sections -fdata-sections -Wall -Wextra \
-			-Wstrict-aliasing=2
-CXXFLAGS := $(ARCH) -std=c++20 -O2 -g -fstrict-aliasing \
-			-ffunction-sections -fdata-sections -Wall -Wextra \
-			-Wstrict-aliasing=2
-ASFLAGS  := $(ARCH) -O2 -g -x assembler-with-cpp
+CFLAGS   := $(ARCH) -std=c17 -O2 -g -fPIE -fstrict-aliasing \
+			-ffunction-sections -fdata-sections -fstack-protector-strong \
+			-Wall -Wextra -Wstrict-aliasing=2
+CXXFLAGS := $(ARCH) -std=c++20 -O2 -g -fPIE -fstrict-aliasing \
+			-ffunction-sections -fdata-sections -fstack-protector-strong \
+			-Wall -Wextra -Wstrict-aliasing=2
+ASFLAGS  := $(ARCH) -O2 -g -fPIE -x assembler-with-cpp
 ARFLAGS  := -rcs
-LDFLAGS  := $(ARCH) -O2 -s -Wl,--gc-sections
+LDFLAGS  := $(ARCH) -O2 -s -pie -fPIE -Wl,--gc-sections,-z,relro,-z,now,-z,noexecstack
 
 PREFIX   :=
 CC       := $(PREFIX)gcc

include/fat_label.h

@@ -0,0 +1,7 @@
+#pragma once
+
+#include "types.h"
+
+
+
+size_t convertCheckLabel(const char *const label, char *dosLabel);

source/fat_label.cpp

@@ -0,0 +1,116 @@
+#include <cstdio>
+#include <cstdlib>
+#include <cwctype>
+#include "types.h"
+
+
+// http://www.unicode.org/Public/MAPPINGS/VENDORS/MICSFT/PC/CP850.TXT
+// Range 0x80-0xFF.
+static const wchar_t cp850Lut[128] =
+{
+	0x00C7, 0x00FC, 0x00E9, 0x00E2, 0x00E4, 0x00E0, 0x00E5, 0x00E7,
+	0x00EA, 0x00EB, 0x00E8, 0x00EF, 0x00EE, 0x00EC, 0x00C4, 0x00C5,
+	0x00C9, 0x00E6, 0x00C6, 0x00F4, 0x00F6, 0x00F2, 0x00FB, 0x00F9,
+	0x00FF, 0x00D6, 0x00DC, 0x00F8, 0x00A3, 0x00D8, 0x00D7, 0x0192,
+	0x00E1, 0x00ED, 0x00F3, 0x00FA, 0x00F1, 0x00D1, 0x00AA, 0x00BA,
+	0x00BF, 0x00AE, 0x00AC, 0x00BD, 0x00BC, 0x00A1, 0x00AB, 0x00BB,
+	0x2591, 0x2592, 0x2593, 0x2502, 0x2524, 0x00C1, 0x00C2, 0x00C0,
+	0x00A9, 0x2563, 0x2551, 0x2557, 0x255D, 0x00A2, 0x00A5, 0x2510,
+	0x2514, 0x2534, 0x252C, 0x251C, 0x2500, 0x253C, 0x00E3, 0x00C3,
+	0x255A, 0x2554, 0x2569, 0x2566, 0x2560, 0x2550, 0x256C, 0x00A4,
+	0x00F0, 0x00D0, 0x00CA, 0x00CB, 0x00C8, 0x0131, 0x00CD, 0x00CE,
+	0x00CF, 0x2518, 0x250C, 0x2588, 0x2584, 0x00A6, 0x00CC, 0x2580,
+	0x00D3, 0x00DF, 0x00D4, 0x00D2, 0x00F5, 0x00D5, 0x00B5, 0x00FE,
+	0x00DE, 0x00DA, 0x00DB, 0x00D9, 0x00FD, 0x00DD, 0x00AF, 0xACCE,
+	0x00AD, 0x00B1, 0x2017, 0x00BE, 0x00B6, 0x00A7, 0x00F7, 0x00B8,
+	0x00B0, 0x00A8, 0x00B7, 0x00B9, 0x00B3, 0x00B2, 0x25A0, 0x00A0
+};
+
+
+
+// Make sure dosStr is big enough!
+static bool wchar2cp850(const wchar_t *wStr, char *dosStr)
+{
+	while(*wStr != L'\0')
+	{
+		const wchar_t wc = *wStr++;
+		if(wc > 0 && wc < 128)
+		{
+			*dosStr++ = wc;
+			continue;
+		}
+
+		unsigned i;
+		for(i = 0; i < 128; i++)
+		{
+			if(wc == cp850Lut[i])
+			{
+				*dosStr++ = 0x80 | i;
+				break;
+			}
+		}
+
+		if(i == 128)
+		{
+			fprintf(stderr, "Error: Can't convert wide character 0x%08" PRIX32 " to CP850.\n", wc);
+			return false;
+		}
+	}
+
+	*dosStr = '\0';
+
+	return true;
+}
+
+size_t convertCheckLabel(const char *const label, char *dosLabel)
+{
+	// Reserve one more char so we can detect if the label is too long.
+	wchar_t wLabel[13];
+	wLabel[12] = L'\0';
+	const size_t wideChars = mbstowcs(wLabel, label, 12);
+	if(wideChars == (size_t)-1)
+	{
+		fputs("Failed to convert label to wide characters.\n", stderr);
+		return 0;
+	}
+
+	if(wideChars > 11)
+	{
+		fputs("Error: Label is too long.\n", stderr);
+		return 0;
+	}
+
+	for(unsigned i = 0; wLabel[i] != L'\0'; i++)
+	{
+		if(iswlower(wLabel[i]) != 0)
+		{
+			fputs("Warning: Label contains lowercase characters.\n", stderr);
+			break;
+		}
+	}
+
+	if(!wchar2cp850(wLabel, dosLabel)) return 0;
+
+	if(*dosLabel == ' ')
+	{
+		fputs("Error: First character in label must nut be a space.\n", stderr);
+		return 0;
+	}
+
+	while(*dosLabel != '\0')
+	{
+		const unsigned char c = *dosLabel++;
+		if(c < 0x20 || c == 0x22 ||
+		   (c >= 0x2A && c <= 0x2C) ||
+		   c == 0x2E || c == 0x2F ||
+		   (c >= 0x3A && c <= 0x3F) ||
+		   (c >= 0x5B && c <= 0x5D) ||
+		   c == 0x7C)
+		{
+			fputs("Error: Label contains invalid characters.\n", stderr);
+			return 0;
+		}
+	}
+
+	return wideChars;
+}

source/main.cpp

@@ -1,10 +1,12 @@
+#include <clocale>
 #include <cstdio>
 #include <cstdlib>
 #include <cstring>
 #include <exception>
 #include <getopt.h>
 #include "errors.h"
 #include "format.h"
+#include "fat_label.h"
 #include "verbose_printf.h"
 
 
@@ -32,6 +34,8 @@ static void printHelp(void)
 
 int main(const int argc, char *const argv[])
 {
+	setlocale(LC_CTYPE, ""); // We could also default to "en_US.UTF-8".
+
 	static const struct option long_options[] =
 	{{"big-clusters",       no_argument, NULL, 'b'},
 	 {    "capacity", required_argument, NULL, 'c'},
@@ -89,29 +93,8 @@ int main(const int argc, char *const argv[])
 				break;
 			case 'l':
 				{
-					if(strlen(optarg) > 11)
-					{
-						fputs("Error: Label is longer than 11 characters.\n", stderr);
+					if(convertCheckLabel(optarg, label) == 0)
 						return ERR_INVALID_ARG;
-					}
-					strncpy(label, optarg, 11);
-					/*for(u32 i = 0; i < 11; i++)
-					{
-						const unsigned char lc = label[i];
-						if(lc < 0x20 || lc == 0x22 ||
-						   (lc >= 0x2A && lc <= 0x2C) ||
-						   lc == 0x2E || lc == 0x2F ||
-						   (lc >= 0x3A && lc <= 0x3F) ||
-						   (lc >= 0x5B && lc <= 0x5D) ||
-						   lc == 0x7C)
-						{
-							fputs("Error: Label contains invalid characters.\n", stderr);
-							return ERR_INVALID_ARG;
-						}
-						// TODO: The label should be encoded in the system's DOS code page. Convert from UTF-8 to DOS code page.
-						// TODO: Check for uppercase chars and give a warning.
-						// TODO: Do not allow the "NO NAME" label?
-					}*/
 				}
 				break;
 			case 'v':