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| import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class ImageHexViewer {
public static void main(String[] args) throws IOException {
String filePath = "C:\\Users\\admin\\Desktop\\sdaf\\1.pdf";
boolean flag = checkImgCrack(new File(filePath));
System.out.println(flag);
}
private static final String regex = "(3c3f.*?706870)";
public static boolean checkImgCrack(File file) throws IOException {
boolean flag = isImageFile(file);
if (!flag) {
return false;
}
FileInputStream fis = new FileInputStream(file);
byte[] imageBytes = new byte[(int) file.length()];
fis.read(imageBytes);
StringBuilder hexString = new StringBuilder();
for (byte b : imageBytes) {
String hex = Integer.toHexString(0xFF & b);
if (hex.length() == 1) {
hexString.append('0');
}
hexString.append(hex);
}
fis.close();
String hex = hexString.toString();
if (null == hex) {
return false;
}
Pattern pattern = Pattern.compile(regex);
Matcher matcher = pattern.matcher(hex);
return matcher.find();
}
private static boolean isImageFile(File file) throws IOException {
FileInputStream input = new FileInputStream(file);
byte[] buffer = new byte[8];
int bytesRead = input.read(buffer);
if (bytesRead < 8) {
return false;
}
if (isJPEG(buffer) || isPNG(buffer) || isGIF(buffer) || isBMP(buffer)) {
return true;
}
return false;
}
private static boolean isJPEG(byte[] buffer) {
return buffer[0] == (byte) 0xFF && buffer[1] == (byte) 0xD8;
}
private static boolean isPNG(byte[] buffer) {
return buffer[0] == (byte) 0x89 && buffer[1] == 0x50 && buffer[2] == 0x4E && buffer[3] == 0x47 && buffer[4] == 0x0D && buffer[5] == 0x0A && buffer[6] == 0x1A && buffer[7] == 0x0A;
}
private static boolean isGIF(byte[] buffer) {
return buffer[0] == 'G' && buffer[1] == 'I' && buffer[2] == 'F' && buffer[3] == '8';
}
private static boolean isBMP(byte[] buffer) {
return buffer[0] == 0x42 && buffer[1] == 0x4D;
}
}
|
