pattern_finder

pattern_finder is a compact library written in Dart language that is primarily used for signature matching and/or wildcard pattern finder in byte streams.

In addition, you can pass an anonymous function that will be called once signature is found. This function only accepts one parameter the 'offset' where pattern was found.

Usage

A simple usage example:

import 'dart:typed_data';
import 'package:pattern_finder/pattern_finder.dart';

main() {
  /* Search for patterns using PatternFinder.Find and PatternFinder.Find_B functions */
  var pattern = PatternFinder.Transform('456?89?B');

  var buf1 = [0x01, 0x23, 0x45, 0x67, 0x89, 0xAB, 0xCD, 0xEF];
  var buf2 = [0x01, 0x23, 0x45, 0x66, 0x89, 0x6B, 0xCD, 0xEF];
  var buf3 = [0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11];

  int foundOffset1 =
      PatternFinder.Find_B(buf1, 8, pattern); // foundOffset1: 2
  int foundOffset2 =
      PatternFinder.Find(buf2, 8, '456?89?B'); // foundOffset2: 2
  int foundOffset3 =
      PatternFinder.Find_B(buf3, 8, pattern); // foundOffset3: -1

  /* Search for patterns using signatures */
  var buf = [
    0x01,
    0x23,
    0x45,
    0x67,
    0x89,
    0xAB,
    0xCD,
    0xEF,
    0x45,
    0x65,
    0x67,
    0x89
  ];

  Signature sig1 = new Signature("pattern1", "456?89?B",
      func: (offset) => print('Found Pattern1!!! @ ${offset}'));
  Signature sig2 = new Signature("pattern2", "1111111111",
      func: () => print('Will I make it?'));
  Signature sig3 =
      new Signature("pattern3", "AB??EF", func: () => print('Found pattern3'));
  Signature sig4 = new Signature("pattern4", "45??67", func: (int offset) {
    // do something
    int new_offset = offset + 4;
    print('Found pattern4!!! Old Offset: ${offset}, New Offset: ${new_offset}');
  });
  List<Signature> signatures = [sig1, sig2, sig3, sig4];

  // Run `Scan` to execute founded signatures function
  SignatureFinder.Scan(buf, buf.length, signatures);

  //  Found Pattern1!!! @ 2
  //  Found pattern3
  //  Found pattern4!!! Old Offset: 8, New Offset: 12
}

License

Copyright (c) 2021 Mbadiwe Nnaemeka Ronald ron2tele@gmail.com

This software is provided 'as-is', without any express or implied
warranty. In no event will the author be held liable for any damages
arising from the use of this software.
Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it
freely, subject to the following restrictions:

1. The origin of this software must not be misrepresented; you must not
claim that you wrote the original software. If you use this software
in a product, an acknowledgment in the product documentation must be
specified.

2. Altered source versions must be plainly marked as such, and must not be
misrepresented as being the original software.

3. This notice may not be removed or altered from any source distribution.

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