Cryptography Stack Exchange
Cryptography Stack Exchange

Questions tagged [crc]

The Cyclic Redundancy Check is a non-cryptographic error-detecting code. While CRCs occasionally appear as parts of a cryptosystem, questions purely about CRCs and other non-cryptographic checksums are off-topic here, and should be asked on Stack Overflow instead.

The Cyclic Redundancy Check is a non-cryptographic error-detecting code.

While CRCs occasionally appear as parts of a cryptosystem, questions purely about CRCs and other non-cryptographic checksums are off-topic here. Such questions may be asked on Stack Overflow instead.

45 questions
3
votes
2 answers

Achieving 32-bit verification code with 16-bit CRC?

I am programming an embedded chip that has a hardware 16-bit CRC module. I have to protect some data bytes $d_0,d_1,...,d_{n-1}$ against corruption caused by sudden loss of power; a 32-bit CRC would provide the level of protection that I need, but…
TonyK
  • 402
  • 2
  • 11
2
votes
2 answers

Reversing N CRC steps

Starting from a known CRC result(let's call it CRC1), could I undo the CRC operations for last N bits, so I could obtain the CRC (let's call it CRC2) of the message sequence without the last N bits. $$ M(x) - message \\ M = \{M1,LastBits\}…
TwoSan
  • 23
  • 2
2
votes
0 answers

How to prove that CRC (with an initial value of zero) is linear?

I understand that, as stated here, CRC is not linear (with respect to XOR operator) in general, because it could be initialized with a non-zero value. I was wondering how to prove linearity, when zero is used as the initial value for CRC. Basically,…
Ali Bababeig
  • 21
  • 3
1
vote
2 answers

Modifying a [CRC32] checksum protected file

I dont want to ask for help without showing how far I came by myself, so this is what I have so far: The file of interest is an encrypted/obfuscated .bin script, which cotains information on certain weaponstats eg. damage or accuracy. It is part of…
dontjudge
  • 11
  • 1
  • 4
0
votes
1 answer

Forming a 64 bit CRC from a 32 bit CRC

Suppose I have a 32 bit CRC function $\text{crc32}(x)$ that satisfies all the properties of a CRC. Suppose also that I am a lazy developer who wants to create a 64 bit CRC function but doesn't want to actually have to implement another CRC, so I…
user101145
  • 1
-2
votes
1 answer

CRC-16-IBM, Reversed 0xA001, Little Endian (DCBA) Implementation

Background I need to implement this algorithm in Node.js, but after searching everywhere I can't find an implementation. Code My first approach was reviewed by a member of StackOverflow and was considered…
Flame_Phoenix
  • 107
  • 1
  • 4