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// Copyright (c) 2009-2017 The OTS Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "config.h"
#if !defined(_MSC_VER)
#if defined(HAVE_CORETEXT)
#include <ApplicationServices/ApplicationServices.h>
#elif defined(HAVE_FREETYPE)
#include <ft2build.h>
#include FT_FREETYPE_H
#include FT_OUTLINE_H
#endif
#else
// Windows
// TODO(yusukes): Support Windows.
#endif // _MSC_VER
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include "opentype-sanitiser.h"
#include "ots-memory-stream.h"
namespace {
#if !defined(_MSC_VER)
#if defined(HAVE_CORETEXT)
int OpenAndLoadChars(
const char *file_name, uint8_t *trans_font, size_t trans_len) {
CFDataRef data = CFDataCreate(0, trans_font, trans_len);
if (!data) {
std::fprintf(stderr,
"OK: font renderer couldn't open the transcoded font: %s\n",
file_name);
return 0;
}
CGDataProviderRef dataProvider = CGDataProviderCreateWithCFData(data);
CGFontRef cgFontRef = CGFontCreateWithDataProvider(dataProvider);
CGDataProviderRelease(dataProvider);
CFRelease(data);
if (!cgFontRef) {
std::fprintf(stderr,
"OK: font renderer couldn't open the transcoded font: %s\n",
file_name);
return 0;
}
size_t numGlyphs = CGFontGetNumberOfGlyphs(cgFontRef);
CGFontRelease(cgFontRef);
if (!numGlyphs) {
std::fprintf(stderr,
"OK: font renderer couldn't open the transcoded font: %s\n",
file_name);
return 0;
}
std::fprintf(stderr, "OK: font renderer didn't crash: %s\n", file_name);
// TODO(yusukes): would be better to perform LoadChar() like Linux.
return 0;
}
#elif defined(HAVE_FREETYPE)
void LoadChar(FT_Face face, int pt, FT_ULong c) {
FT_Matrix matrix;
matrix.xx = matrix.yy = 1 << 16;
matrix.xy = matrix.yx = 0 << 16;
FT_Set_Char_Size(face, pt * (1 << 6), 0, 72, 0);
FT_Set_Transform(face, &matrix, 0);
FT_Load_Char(face, c, FT_LOAD_RENDER);
}
int OpenAndLoadChars(
const char *file_name, uint8_t *trans_font, size_t trans_len) {
FT_Library library;
FT_Error error = FT_Init_FreeType(&library);
if (error) {
std::fprintf(stderr, "Failed to initialize FreeType2!\n");
return 1;
}
FT_Face trans_face;
error = FT_New_Memory_Face(library, trans_font, trans_len, 0, &trans_face);
if (error) {
std::fprintf(stderr,
"OK: FreeType2 couldn't open the transcoded font: %s\n",
file_name);
return 0;
}
static const int kPts[] = {100, 20, 18, 16, 12, 10, 8}; // pt
static const size_t kPtsLen = sizeof(kPts) / sizeof(kPts[0]);
static const int kUnicodeRanges[] = {
0x0020, 0x007E, // Basic Latin (ASCII)
0x00A1, 0x017F, // Latin-1
0x1100, 0x11FF, // Hangul
0x3040, 0x309F, // Japanese HIRAGANA letters
0x3130, 0x318F, // Hangul
0x4E00, 0x4F00, // CJK Kanji/Hanja
0xAC00, 0xAD00, // Hangul
};
static const size_t kUnicodeRangesLen
= sizeof(kUnicodeRanges) / sizeof(kUnicodeRanges[0]);
for (size_t i = 0; i < kPtsLen; ++i) {
for (size_t j = 0; j < kUnicodeRangesLen; j += 2) {
for (int k = 0; k <= kUnicodeRanges[j + 1] - kUnicodeRanges[j]; ++k) {
LoadChar(trans_face, kPts[i], kUnicodeRanges[j] + k);
}
}
}
std::fprintf(stderr, "OK: FreeType2 didn't crash: %s\n", file_name);
return 0;
}
#endif
#else
// Windows
// TODO(yusukes): Support Windows.
#endif // _MSC_VER
} // namespace
int main(int argc, char **argv) {
if (argc != 2) {
std::fprintf(stderr, "Usage: %s ttf_or_otf_filename\n", argv[0]);
return 1;
}
// load the font to memory.
const int fd = ::open(argv[1], O_RDONLY);
if (fd < 0) {
::perror("open");
return 1;
}
struct stat st;
::fstat(fd, &st);
const off_t orig_len = st.st_size;
uint8_t *orig_font = new uint8_t[orig_len];
if (::read(fd, orig_font, orig_len) != orig_len) {
std::fprintf(stderr, "Failed to read file!\n");
return 1;
}
::close(fd);
// transcode the malicious font.
static const size_t kBigPadLen = 1024 * 1024; // 1MB
uint8_t *trans_font = new uint8_t[orig_len + kBigPadLen];
ots::MemoryStream output(trans_font, orig_len + kBigPadLen);
ots::OTSContext context;
bool result = context.Process(&output, orig_font, orig_len);
if (!result) {
std::fprintf(stderr, "OK: the malicious font was filtered: %s\n", argv[1]);
return 0;
}
const size_t trans_len = output.Tell();
return OpenAndLoadChars(argv[1], trans_font, trans_len);
}
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