-
Notifications
You must be signed in to change notification settings - Fork 15
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
* Add CRC32 class and tests. * Improve CRC check * Add CRC32 class * Update target framework for tests. * Updating tests to look for the correct target framework * Making class static * Now, every validator will have one private httpclient instead of sharing between different classes Co-authored-by: Eddy Nakamura <ednakamu@microsoft.com> Co-authored-by: Eddy Nakamura <eddynaka@gmail.com>
- Loading branch information
3 people
committed
Aug 1, 2021
1 parent
285b41a
commit d7da9f5
Showing
16 changed files
with
200 additions
and
89 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,96 @@ | ||
| // Copyright (c) Microsoft. All rights reserved. | ||
| // Licensed under the MIT license. See LICENSE file in the project root for full license information. | ||
|
|
||
| using System.Text; | ||
|
|
||
| namespace Microsoft.CodeAnalysis.Sarif.PatternMatcher.Sdk | ||
| { | ||
| public static class Crc32 | ||
| { | ||
| // https://crc32.online/ | ||
| // https://github.com/force-net/Crc32.NET | ||
| // https://en.wikipedia.org/wiki/Cyclic_redundancy_check | ||
| // This is the 'reversed representation' polynomial for | ||
| // little-endian implementations, i.e., the bitwise | ||
| // reflection of 0x04C11DB7; | ||
| private const uint Crc32Polynomial = 0xedb88320u; | ||
|
|
||
| private static readonly uint[] Crc32Table = CreateCrcTable(Crc32Polynomial); | ||
|
|
||
| public static uint Calculate(string text) | ||
| { | ||
| byte[] data = Encoding.ASCII.GetBytes(text); | ||
| return Calculate(data); | ||
| } | ||
|
|
||
| public static uint Calculate(byte[] buffer) | ||
| { | ||
| return Calculate(0, buffer, 0, buffer.Length); | ||
| } | ||
|
|
||
| public static uint Calculate(uint checksum, byte[] buffer, int offset, int length) | ||
| { | ||
| checksum ^= 0xffffffffU; | ||
|
|
||
| while (length >= 16) | ||
| { | ||
| uint a = Crc32Table[(3 * 256) + buffer[offset + 12]] ^ | ||
| Crc32Table[(2 * 256) + buffer[offset + 13]] ^ | ||
| Crc32Table[(1 * 256) + buffer[offset + 14]] ^ | ||
| Crc32Table[(0 * 256) + buffer[offset + 15]]; | ||
|
|
||
| uint b = Crc32Table[(7 * 256) + buffer[offset + 8]] ^ | ||
| Crc32Table[(6 * 256) + buffer[offset + 9]] ^ | ||
| Crc32Table[(5 * 256) + buffer[offset + 10]] ^ | ||
| Crc32Table[(4 * 256) + buffer[offset + 11]]; | ||
|
|
||
| uint c = Crc32Table[(11 * 256) + buffer[offset + 4]] ^ | ||
| Crc32Table[(10 * 256) + buffer[offset + 5]] ^ | ||
| Crc32Table[(9 * 256) + buffer[offset + 6]] ^ | ||
| Crc32Table[(8 * 256) + buffer[offset + 7]]; | ||
|
|
||
| uint d = Crc32Table[(15 * 256) + ((byte)checksum ^ buffer[offset])] ^ | ||
| Crc32Table[(14 * 256) + ((byte)(checksum >> 8) ^ buffer[offset + 1])] ^ | ||
| Crc32Table[(13 * 256) + ((byte)(checksum >> 16) ^ buffer[offset + 2])] ^ | ||
| Crc32Table[(12 * 256) + ((checksum >> 24) ^ buffer[offset + 3])]; | ||
|
|
||
| checksum = d ^ c ^ b ^ a; | ||
| offset += 16; | ||
| length -= 16; | ||
| } | ||
|
|
||
| while (--length >= 0) | ||
| { | ||
| checksum = Crc32Table[(checksum ^ buffer[offset++]) & 0xFF] ^ (checksum >> 8); | ||
| } | ||
|
|
||
| checksum ^= 0xffffffffU; | ||
|
|
||
| return checksum; | ||
| } | ||
|
|
||
| private static uint[] CreateCrcTable(uint polynomial) | ||
| { | ||
| var table = new uint[16 * 256]; | ||
|
|
||
| for (uint i = 0; i < 256; i++) | ||
| { | ||
| uint res = i; | ||
|
|
||
| for (int t = 0; t < 16; t++) | ||
| { | ||
| for (int k = 0; k < 8; k++) | ||
| { | ||
| res = (res & 1) == 1 | ||
| ? polynomial ^ (res >> 1) | ||
| : (res >> 1); | ||
| } | ||
|
|
||
| table[(t * 256) + i] = res; | ||
| } | ||
| } | ||
|
|
||
| return table; | ||
| } | ||
| } | ||
| } |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Oops, something went wrong.