Questions tagged [integrity]

In a cryptographic sense, integrity means unimpaired and complete.

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Implement true serverless (decentralized) online multiplayer game with cryptography

TLDR, this will be a discussion rather than my private problem. Nowadays, most game developers or publishers have central servers to manage player transactions such as movement, mouse position, and so ...
Muhammad Ikhwan Perwira's user avatar
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1 answer
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Signing a file vs. a manifest of cryptographic hashes

I’m interested in the tradeoffs of signing individual files vs. signing a manifest of cryptographic hashes and file names. Let’s say I do some work that results in a handful of files (10s to hundreds),...
baseboard49's user avatar
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Looking for a modifiable signature!

I am a graduate student and have encountered some problems in my research. When I generate a signature on the data block of the file, and the signature is composed of the user's private key, the data ...
nan gan's user avatar
1 vote
1 answer
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Hash-Then-Encrypt or Encrypt-Then-Hash on Keyed Hash Functions

I have seen other answers here on Stack Exchange regarding MAC-Then-Encrypt vs. Encrypt-Then-MAC (and this article regarding MAC-Then-Encrypt padding oracle attacks on SSL) as well as generic Hash-...
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Why does symmetric encryption not provide authentication and integrity? Is it only this type of encryption or cryptology in general have this issue?

Studying for Cryptology and came across a presentation regarding on "Integrity vs Authenticity" where the discussion briefly mentions how Encryption "does not provide integrity or ...
omar7439's user avatar
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Answering boolean question without knowing "Who" answer [closed]

Can cryptography solve this problem? Two people are chatting, Mr. X and Ms Y. They give each other a CRC16 hash of someone's name initials and salt a random number at the end (suffix). Ms Y: "I ...
Muhammad Ikhwan Perwira's user avatar
1 vote
1 answer
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DTLS 1.2 Cipher Suites With AES-GCM – What data (if any) is passed to the AES-GCM cipher as the Additional Authentication Data?

It is DTLS 1.2 version question of this question. I know from 4.1.2.4. of RFC 5246 (DTLS 1.2) AEAD Ciphers can be used in DTLS 1.2 exactly the same with TLS 1.2. In TLS 1.2 AAD = seq_num + ...
Jounghoo Lee's user avatar
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Does the order of validations and MAC with clear text matter?

I have a request in which I get a series of data in clear (nothing encrypted) and a MAC / authentication tag. The question is whether the MAC should be validated first or if the fields are filled in ...
Felipe Rodriguez Fonte's user avatar
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Does the private blockchain have to follow client-server model when considering BFT?

I'm a newbie, currently interested in data security & integrity. I'm quite new to blockchain and distributed system theories, and suffering from some unclear doubts/questions on the fault-tolerant ...
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Security proof of the Schnorr Signature

How Schnorr signature security can be proved for signature forgery, replacement, and Replay attacks?
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How do Pre-image, Second pre-image and collision resistance actually work? How does this affect data integrity?

I'm working on this past exam paper and found this question about pre-image resistance and its relation to data integrity: Displaying the hash of a file on a website in order to provide data integrity ...
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How can you prove that a certain file was downloaded from a certain website?

Let's say you downloaded a file from a certain website, and later the website claims that it didn't made that file available, is there any way to prove that the website is lying? Example 1: You ...
TimestampQuestion's user avatar
2 votes
1 answer
923 views

What does AES-GCM provide?

I am wondering does AES-GCM which uses Authenticated Encryption provide us with all 3 properties (Authenticity, Confidentiality, and Integrity), or does it not provide integrity?
CryptoGuru's user avatar
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1 answer
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Hash Function Vs Signature Vs MAC?

I read: What are the differences between a digital signature, a MAC and a hash? and Found this amazing answer: https://crypto.stackexchange.com/a/5647 But one question remains: I know that for huge ...
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Trustless deterministic fingerprint of additive subgroup of $GF(2^n)$

Suppose I have $k$ blocks $B_i$ each consisting of $n$ bits. For erasure code purposes I'd like to be able to produce a computationally binding deterministic hash/fingerprint/digest $H$ such that $\...
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Get Pixel Data from JPG/JPEG but still bring the integrity? [closed]

As far as I know, JPG is a lossy image compression format Meanwhile, BMP is a generally uncompressed image format, whose file structure consists of bitmapFileHeader (14 bytes) and bitmapInfoHeader (40 ...
akez's user avatar
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Has reducing MAC size and increasing message size the same effect on security?

I am evaluating ways to reduce the overhead of (H)MACs on small messages. I was primarily wondering if there is a difference between halving the MAC length or keeping the same MAC length but using it ...
Septatrix's user avatar
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1 answer
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Does CMS AuthEnvelopedData type provide message authentication?

I was looking through the S/MIME Message specification (RFC 8551) to find out what security services it offers. Section 2.4.4 of this document describing AuthEnvelopedData content type (which uses the ...
Kirill Khakimov's user avatar
1 vote
4 answers
925 views

Does SSL connection provide integrity?

I'm new to cryptography and I'm trying to implement a secure chat application using OpenSSL. I want to ensure that public messages (which will be shown to all users) cannot be altered during ...
David's user avatar
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Quantum secure algorithms

I want to know if the below algorithm , secure against quantum computing attack, and how I can compute the running time for the original algorithm and the proposed attack Source: Yan Zhu, HuaiXi Wang,...
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Prove that secure authenticated encryption system composed with itself is secure

Suppose $(E,D)$ provides authenticated encryption with key space $K$. Define $(E',D')$ with key space $K^2$ as follows: $$ E'((k_1,k_2),m) = E(k_2,E(k_1,m)) \\ D'((k_1,k_2),c) = \begin{cases} D(k_1,E(...
ByteEater's user avatar
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2 answers
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Is there a way to sign a message so that any subset can be verified?

I would like to know if there's a scheme that can allow something like the following: Alice signs a message $M$ with signature $S$ and gives it to Bob and Mallory. Bob can present any subset of $M$, ...
Joseph Kaptur's user avatar
1 vote
1 answer
795 views

Can ChaCha20 provide integrity?

I have read that in general stream ciphers do not provide data integrity. Can ChaCha20 be implemented in such a way (perhaps like counter mode with message authentication in AES) to provide this?
WireInTheGhost's user avatar
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getting key $k_{2}$ somehow definitely compromise authentication scheme and attacker can see cipher text now...so not secure

I was going through this question of nested encryption: Given $\Pi$ = $({Gen}, {Enc}, {Dec})$ is authentication encryption we have designed new scheme $\Pi^{'}$ = $({Gen^{'}}, {Enc{'}}, {Dec{'}})$ ...
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Is the tag in a MAC scheme a fixed size?

I've been reading up on MAC schemes. But I cannot seem to find out whether the tag's that are output by running MAC(m) is of a fixed size? I can find a lot of stuff talking about the tag space being a ...
crypto_confuse's user avatar
1 vote
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Is Poly1305 enough for cascading ciphers? [duplicate]

ChaCha20 along with Poly1305 provides confidentiality and integrity. Now suppose I cascade AES on top of ChaCha20. Is it safe to assume that the Poly1305 MAC is still secure, even if I cascade ...
Evan Su's user avatar
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1 answer
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How can JWE support an integrity check given that it uses a public key to encrypt the message?

As far as I know JWE (JSON Web Encryption) supports both integrity and confidentiality. I agree about the confedintiality because only the recepient with a private key can decrypt a message. What ...
Abzal Serekov's user avatar
2 votes
2 answers
146 views

What security guarantees do blockchains provide for data storage?

When it's considered, like here a project where a user needs to store a (small piece of data) on a blockchain what does that really mean from a cryptographer's perspective? What security guarantees ...
fgrieu's user avatar
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MAC forgery using the DES's Complementary Property

I've started reading on MACs and working on a problem where given a MAC construction as $H_0=IV$ and for every $i>0$ $H_i=H_{i−1} \oplus E_{M[i]}(H_{i−1})$ and the tag is $(IV,E_{k_1}(H_ℓ))$, I ...
Alex's user avatar
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6 votes
1 answer
870 views

OpenSSL FIPS integrity check

As far as I know, FIPS requires a set of self tests (POST) to verify the cryptographic algorithms permitted and the integrity of the module. These tests are performed at run-time, so OpenSSL does a ...
Guille's user avatar
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1 vote
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Provable Data Possession

While Provable Data Possession seems to be a very useful and interesting tool for ensuring integrity of data outsourced into Cloud providers, I have never seen a reputed Cloud provider talk about this ...
Van-Hoan HOANG's user avatar
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35 views

Integrity for mixture of encrypted/unencrypted database fields

I have multiple blobs each (symmetrically) encrypted with its own randomly generated key. Now I want to encrypt these blob keys with user keys and store them in a database. A table could have the ...
darkdragon's user avatar
1 vote
1 answer
415 views

Is MAC process different for symmetric and asymmetric?

Message Authentication Code as far as I know works on the shared secret key. Do they work in the same way. Is there no difference between symmetric and asymmetric processes. Can anyone please explain ...
Aditya Shrivastava's user avatar
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2 answers
401 views

If I want Integrity and Authentication AND Non-Repudiation, can the Digital Signature be based on the MAC?

Let's say I'm making a digital signature like this: hash = hash(message) digital signature = encrypt_with_private_key(hash) where the private key is Alice's ...
if_dogs_could_swim's user avatar
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1 answer
508 views

Boolean XOR function a valid way to verify the integrity of a message

Does the Boolean XOR function represent a valid way to verify the integrity of a message ?
Mohanish Nehete's user avatar
1 vote
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61 views

Using cryptography to protect database integrity

I'm designing a micro-services system where each service manages some set of entities (User, Account, e.g). I want to be able to verify the authenticity of entity identifiers (e.g User-Id and Account-...
somdoron's user avatar
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2 answers
4k views

How do AES and DES ensure data integrity?

I have been trying to study for cryptographic symmetric algorithms (AES,DES) and came up with a question whether these two on their own ensure integrity (i.e data has not been altered). Do these two ...
Javazzs's user avatar
1 vote
2 answers
531 views

Can a MAC be used as a HMAC?

I am reading through an information security book right now, and a confusing question poses itself to me: "Could you use a MAC as a HMAC? That is, does a MAC satisfy the same properties that a ...
John Michaels's user avatar
1 vote
1 answer
79 views

Integrity of format preserving Encryption

In this question regarding integrity of FPE, the main point of the answer is that: FFX is not malleable. [...] FFX can provide integrity protection in very limited circumstances. So I was ...
Marc Ilunga's user avatar
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3 votes
1 answer
225 views

Information security evaluation

I saw this exercise for evaluating the security(confidentiality, integrity, authenticity, and non-repudiation) of some schemes: ENC(M) || SignA(ENC(M)) ...
theantomc's user avatar
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1 vote
2 answers
446 views

SHA-3 for Integrity

We used to use CRCs to check the integrity of files. For safety analysis we could associate a probability for detecting a corrupted bit in a large file. Now we are using an RSA Signed SHA-3 hash for ...
Sal Navidi's user avatar
1 vote
0 answers
35 views

Keeping a backup of asymmetric keys with the help of a certificate authority without losing the privacy

First I'll explain the problem, then I will also give a solution(it might be wrong) I've found for it, you let me know what you think about this solution and whether you have a better one. Assume a ...
aderchox's user avatar
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2 votes
2 answers
475 views

Does stronger cryptographic hashes also imply being better at verifying integrity?

What I know so far Fact 1) I know that all cryptographic hash functions have the following properties They are many-to-one in nature They produce fixed size outputs Given an output ...
AlanSTACK's user avatar
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3 answers
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AES, is this method to say "The password you entered is wrong" secure?

(TL;DR at the end) Let's say the plaintext hello is encrypted with AES (CFB mode). I noticed that decryption works no matter the given password! Of course if the ...
Basj's user avatar
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0 votes
1 answer
173 views

Best method for checking integrity of 50 GiB files?

I'm making backups of compressed data (using ZPAQ), some compressed archives are large (50 GiB) I was just going to use sha3sum -a 512, for example: ...
Charles D. Ward's user avatar
1 vote
1 answer
177 views

How reassuring is CRC-then-XTS as authenticated encryption?

It is known that the "xz" compression format embeds a checksum in the compressed file to verify integrity during decompression or standalone testing. The algorithm of the checksum can be one of: CRC32,...
DannyNiu's user avatar
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345 views

How to validate the authenticity and integrity of an XML document?

I am working on a C++ desktop application that reads an XML (also created by my org) from a public server (does not require authentication). I would like to make sure that the downloaded XML has not ...
Vivek Kumar's user avatar
2 votes
1 answer
1k views

How are AEAD, GCM, CBC, Poly1305, EtM, MtE and E&M related?

I am using OpenSSL 1.1.1 to implement a TLS 1.3 communication module so I tried to learn how data integrity and authentication is ensured. I read a lot about AEAD, GCM, CBC, Poly1305, EtM, MtE and E&...
Sylvester's user avatar
1 vote
1 answer
149 views

Ensure Data Integrity In An ECDH Key Excange

Been playing around with the inner workings of onion routing and I have a problem. If I wanted to send the 2nd node of a relay network an ephemeral ECC public key, it has to go through node 1, so that ...
SamG101's user avatar
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1 vote
0 answers
178 views

SHA256 creates a unique hash for two *.wim that have identical content - are there better methods for verifying *.wim contents? [closed]

I'm trying to verify that the contents of a Windows Image are identical for two WIM files; however, I think the timestamps for the file modifications are affecting the final checksums--even though the ...
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