Questions tagged [checksum]

A checksum is a value created from a binary file that can be used to detect errors especially occurred in the transmission.

Filter by
Sorted by
Tagged with
3
votes
2answers
833 views

How easy is it to fake a file hashed with three functions, CRC32, MD5 and SHA-1?

File-A is hashed with CRC32, MD5 and SHA-1. How easy is it to create a fake file-B that has the same hashes of file-A? CRC32, MD5 and SHA-1? Can an average PC with a GPU calculate a triple hash ...
0
votes
1answer
32 views

How to do the WOTS checksum

As far as I understand, the Winternitz one-time signature is made by: Making an array of private keys. Making an array of public keys by hashing each private key X times, X being the number of ...
0
votes
0answers
48 views

Checksum - School Project

I'm working on a challenge at school on Internet, to learn programming and all security issue: "An api request is protected by checksum" and we have to bypass this. The checksum format is ...
1
vote
1answer
62 views

Remote Attestation: when to use Checksum and when to use a Cryptographic Hash function?

In computer security applications, to check the integrity of a specific data/program binary, a cryptographic hash function is normally deployed to generate a digest and compare it with a reference ...
1
vote
1answer
104 views

BIP 39: If I mix my 24 seed phrase with another 24 words, will the checksum property allow an attacker to retrieve the original seed phrase?

Assume that I have a 24-word passphrase that I want to store securely but online by mixing it with another 24 words in a manner only I know. Does the checksum property somehow help an attacker to ...
-1
votes
1answer
191 views

PGP private key format

I have a PGP Private Key from Bob. ...
4
votes
3answers
1k views

Is it possible to fake any file's SHA-256 checksum with a length extension attack?

Can a fake SHA-256 checksum be created trivially for any file by attacker after padding some data after original file i.e. using length extension attack? E.g: Alice creates fake linux installation ...
0
votes
0answers
26 views

How Should Multiple Checksums Be Performed On the Same Data?

I am using CRC32 to verify the integrity of received UDP packets. Along with the generator polynomial, the sender will also specify how many checksums to perform on the sent data, as well as what ...
0
votes
3answers
61 views

Is there an accepted way to cryptographically enforce tracked changes on a document?

I'm working on a document-editor project, and I would like to add a feature to lock tracked changes, similar to Microsoft Office. The goal is to allow one user to lock tracked changes with a password,...
0
votes
0answers
17 views

Check correctness of data using only publicly known variables and a server response

A smart contract (a publicly known program) needs to check if the data D is correct (belongs to some fixed set). It is by definition correct if our trusted server checks it and decides it's correct. ...
0
votes
1answer
824 views

Is CRC32C (any) better than CRC32(B)?

Is CRC32C (any) better than CRC32(B)? I read that CRC32C (alias Castagnoli) is better than CRC32 (sometimes referred as CRC32B) in detecting errors but what that exactly means and how to check it ...
1
vote
3answers
425 views

Identifying identical files without reading them completely

Imagine the following situation: there are many "big" files (100Gb+) lying on 2 different remote servers you have no direct access to these files you can only read a small amount of each file (e.g. ...
1
vote
1answer
123 views

Winternitz One Time Signature

I happened to watch Mr. Bill Buchanan lecture that explains Winternitz one time signature scheme (https://www.youtube.com/watch?v=eqMMlcN4zSc). The scheme shown in the lecture is susceptible to ...
1
vote
3answers
656 views

Do all files have a hash / checksum?

I am curious If every single digital file has a hash and/or a checksum. When verifying my downloaded files using hdiutil on mac os, about 90% of my files report some sort of checksum. However, when i ...
5
votes
2answers
914 views

Is it feasible to get a hash collision for CRC32, MD-5 and SHA-1 on one file?

I'm aware that individually, each has its weaknesses (especially CRC32), but is it feasible that a file could be created to falsely match all three?
0
votes
3answers
943 views

Are LRC (Longitudinal Redundancy Check) or CRC (Cyclic Redundancy Check) of any use in modern day computing?

I am currently learning about the history of Data integrity / Error detection. In the old days of tape drives, LRC was used for error detection. They were also used (at certain point in time) for ...
6
votes
2answers
348 views

Verify partial message given hash of full message

I need to verify partial downloads (retrieved sequentially), given a (preferably short) hash of the complete download. Given a message $m_0 \mathbin\| m_1 \mathbin\| m_2 \mathbin\| \cdots$, hash ...
3
votes
3answers
1k views

Suitable 16-bit checksum?

I am writing a toy1 transport protocol and I am trying to implement a feature whereby: A 16-bit checksum is included in every packet. This checksum can be extended to be 48-bit if the data is large, ...
5
votes
3answers
3k views

Blake2 vs md5 for checksum / file integrity

I'm working on something that requires computing a checksum / file integrity. I've heard MD5 was no longer recommended. Should I use Blake2 instead? Is there a specific variant of Blake2 I should use ...
1
vote
0answers
128 views

How can I calculate the feasibility of brute-forcing missing secret shares against the secret checksum?

Secret sharing has the problem of player cheating, where a forged share $s'_i$ can be sent to generate a fake secret $m'$ during reconstruction (and the cheaters can even collude to generate the real ...
1
vote
2answers
391 views

Why does WOTS+ need a checksum during signing operation?

I was reviewing WOTS+ scheme for consideration in our private blockchain, and noticed that it had a small overhead of calculating a checksum as seen in the following pseudocode excerpt from the ...
3
votes
3answers
139 views

How to calculate a multiple-character checksum for authentication using a tabula recta?

I am not sure if this is possible to do using a tabula recta, but I would like to know how to calculate a multiple-character checksum of a text. For a single-character checksum, it's easy. You just ...
4
votes
1answer
2k views

Why do digital signatures use a hash algorithm instead of a checksum?

Based on my knowledge, all digital signature algorithms use a hash function to sign a message, and then encrypt the hash result. So why do these algorithms not use a checksum instead of a hash ...
12
votes
2answers
6k views

Checksum vs. non-cryptographic hash

What are the differences between checksums (e.g. Fletcher, Adler, CRC), non-cryptographic hashes (e.g. xxHash, MurmurHash, CityHash) and cryptographic hashes (e.g. MD5, SHA1, SHA3)? I am familiar ...
3
votes
0answers
409 views

Optimal way to get checksum digits from hash?

Let msg be some data we want to hash using an arbitrary digest size algorithm such as blake2b. From that hash, we would like to compute a checksum field with n decimal digits. If we suppose that the ...
3
votes
1answer
1k views

Using checksum instead of hash for authenticating ciphers

Lets assume for a specific situation we cannot use authenticated encryption like GCM ... If we were to use CTR, what would you think of using a checksum on the plaintext then encrypt the whole. The ...
3
votes
0answers
163 views

Can XTS + checksum be used for authenticated encryption?

Is it possible to use XTS + a checksum for authenticated encryption? Specifically, it seems like a good $n$ bit checksum applied before encryption should ensure that any change to the ciphertext will ...