instruction stringlengths 32 27.2k |
|---|
Summary: The operation of the Enigma Bombe is well documented. I manage to use it and a candidate checking machine to recover the plugboard pairs and the ring setting for the fast rotor. I struggle to recover ring settings for the slow and the middle rotors.
Question: Where can I find out more technical details on the ... |
I am working on a chat feature to use both post quantum cryptography along with RSA, and want to confirm my thoughts.
As these algorithms haven't been fully battle tested, I have decided to use a combination of both PQE and usual public, secret key cryptography
I decided upon the best algorithms to use for security.
S... |
I'd like for two machines on a network to be able to prove to each other that they both have knowledge of a pre-shared secret, without revealing the secret to each other. Let's assume that all traffic over the connection between the parties, A and B, is encrypted.
Here are the steps I'm currently imagining:
1. A->B: no... |
I have been researching the best encryption to use in a .NET application for managing a sensitive database field (column). This encryption is on top of e.g. AWS at-rest encryption applied to the whole of the database and is aimed at frustrating use of the sensitive data by anyone other than the application (which knows... |
I'm drafing an RFC for a low computation crypto algorithm, intended for low power bluetooth communication. Likely without a connection using advertisements only.
It's going to include raw C code examples so it should be quite portable.
Is there a good site to post my RFC to, where it will be more visible than say, my d... |
assuming that I have an RSA key of length 4k bit which I'm interested to wrap using AES-GCM, and I have a (limited) AES-GCM cipher which can only encrypt limited input in size (say 256-bit/512-bit input) per invocation.
Is there a way/conditions to fulfill when splitting this 4k bit key into smaller keys to fit my (lim... |
Disclaimer: I first posted this question on security.stackexchange some minutes ago but deleted it, this is probably a better place for it.
My goal is to use JWE with hybrid encryption (ECDH+AES) for exchanging sensitive data with another party. However, the example code I can find for various Java libraries doesn't ma... |
When we take the coin flip in Blum's algorithm in "Coin flipping by telephone a protocol for solving impossible problems", where Alice and Bob both want ownership over the same car, then one party (the adversary / Alice) can abort the protocol. Provided there does exist a powerful third party (e.g. the law), the protoc... |
The PLONK paper uses the term preprocessed polynomial a lot of times.
For e.g. page 14
The protocol definition includes a set of preprocessed polynomials $g1, . . . , g_l \in F<d[X]$
Page 20
Preprocessed polynomials: The polynomial $S_{ID} \in F<n[X]$ defined by $S_{ID}(\mathbf g^i) = i$ for each $i \in [n]$ and... |
I'm trying to understand some cryptographic properties of the s-box so I can have my own code. Example of balanced properties I read in this document that they say
A boolean function S : $ GF(2^n) $ $ \to $ $ GF(2) $ is called balanced if the output
set contains equal number of ones and zeros in the corresponding tru... |
I am working with lossy ID-schemes and their security in the QROM. Following the article of Kiltz et al. , I am at a loss of the number 8 appearing in most reductions throughout the article. I know it comes from the Generic Search Problem for Bounded Probabilites, however how?
The Lemma from the article as wee as the g... |
I am working on MPCs (multi party computation) in crypto, and now I am developing a implementation of GG 18.
In sign phase, algorithm needs MtA (Multiplicative to Additive) and uses a Paillier key pair for this.
Paillier uses modulus $N$ ($N=p_1 * p_2$†, prime numbers drawn at key generation). But we need to consider t... |
From this blog post: https://medium.com/@VitalikButerin/exploring-elliptic-curve-pairings-c73c1864e627
if P = G * p, Q = G * q and R = G * r, you can check whether or not p * q = r, having just P, Q and R as inputs.
How?
It's easy to see p * Q = q * P = R. But I don't see the leap to proving p * q = r.
|
In a previous question, I asked how to implement arbitrary s-box in side-channel-free fashion. The code I posted in the question loops over all 256 values of a byte to avoid timing channel, and I want to change it to loop over the values of a word.
Before getting carried away and lost, I'm considering lazy-initializing... |
Passkeys have this complicated QR code + Bluetooth dance to enroll a new device which seems like it ought to be securely creating a key on the device in a TPM.
However the messaging around "sync" seems to suggest that while that is happening, the device key is only used to encrypt a software key which is encrypted and ... |
I am working on manual decryption of application data in TLS 1.3 by going through example in RFC8448. I successfully derived and expanded key and IV, but the IV in examples is only 12 bytes long instead of 16, which is required for AES-128-GCM.
|
I am new at cryptography and start to learn some terms. I just saw an question in the book and didn't got a clue about this question. Could someone can explain me the answer of this question? Because all of the questions seems to be fine for me.
Assuming the block length is 8 bytes (L = 8) Which of the following is/are... |
I have stuck in two problems when understanding the noise management of BFV scheme, and I don't have any idea about the two problem, help me please.
Problem 1:
In the Lemma 3 , the paper demonstrates that the norm of the noise after multiplying two ciphertexts $ct_0$ and $ct_1$ is $\left \|v_{mul}\right\|$=$E\cdot\del... |
From the PLONK paper.
Page 29, Round 3
The paper doesn't explain the need or the use of the quotient challenge $\alpha$.
I understand why each of the polynomials is multiplied by $\frac {1}{Z_H}$ but don't understand why the second is also multiplied by $\alpha$ & the last by $\alpha^2$ - what purpose does the quotien... |
While exploring secp256k1, I came across what seems like the official definition at https://www.secg.org/, specifically in https://www.secg.org/sec2-v2.pdf. In terms of authorship, the document only contains references to the Standards for Efficient Cryptography group and Certicom (acquired by Blackberry). However, man... |
In this image, It describes the basic idea of an iterative hash function. I am confused as to why the i value is set to be m+t+1 as default. Specifically, where does the 1 come from as m+t is just the arbitrary output size + t the message chunk size but the 1 im confused about
|
I try to understand a oracle Padding Oracle Attack example. I try to solve this question but I didn't figure out the answer.
A 7-byte message is padded per PKCS#5 and encrypted using the CBC mode of operation. The resulting ciphertext is
0x07 06 05 04 03 02 01 01, 0x08 09 0A 0B 0C 0D 0E 0F
Assume an Attacker modified t... |
What is meant by "supported groups" in the section 4.2.7. "Supported Groups" of RFC 8446:
/* Finite Field Groups (DHE) */
ffdhe2048(0x0100), ffdhe3072(0x0101), etc:
Is the digits - 2048, 3072 (and groups) etc - are simply numbers of bits of the parameter p (module) in DF algorythm or something else ?
|
Section 2 of RFC 8446 says about the phase "Key Exchange": … Everything after this phase is encrypted.
The "Certificate" message is sent after "Key exchange" as the scheme in that section shows. So it seems to be encrypted.
I am confused that I haven't found a mention of certificate encrypting in the "Certificate" sec... |
The sequence number should be a 64 bit number in every TLS record, but the record header layer is only 5 bytes long and I am looking at a Wireshark pcap, where the TLS record only includes the header and encrypted application data. There is no sequence number.
|
I'm developing a custom Authentication Socialite ADFS Provider using OpenID Connect: Authentication Flow.
Since I have a TLS connection between the client App and the Authentication server that issues the token, what is the point of verifying the access token signature?
From my perspective, the connection is already au... |
What are some ways to produce a pre-determined sequence of a large number of dice rolls (on the order of 100-1000 times) using biased dice or a biased human roller given the constraints that multiple dice (more than 2) have to be projected in one go from a height of at least 1 meter onto a transparent (acrylic/glass) p... |
Suggested by u/HolgerBier on reddit
Is it unpredictable enough or too difficult to manipulate (as in more than a few hundred million USD) to have a sequence of blocks?
|
I'm looking for a mechanism for a type of cert/key signing, where multiple keys need to sign/encrypt something, and a final key/method does not product a valid confirmation unless all those keys did sign/encrypt.
So maybe something like
raw data
action by key1
action by key2
action by keyN
action by final user/system
... |
I've been studying the Schnorr signature scheme and recently came across an example that uses the STROBE protocol. In the classic version of Schnorr signatures, the challenge e is calculated as e = H(m || r), where m is the message, r is an ephemeral value, and H is a cryptographic hash function. However, in the STROBE... |
This is https://github.com/kokke/tiny-AES-c The column mixing function in the AES algorithm implemented.
static uint8_t xtime(uint8_t x)
{
return ((x << 1) ^ (((x >> 7) & 1) * 0x1b));
}
// MixColumns function mixes the columns of the state matrix
static void MixColumns(state_t *state)
{
uint8_t i;
uint8_t ... |
For EC Pedersen commitment: The two generators are G and H. Two messages and randomness are $m_1$, $m_2$, $r_1$, $r_2$,
so the two Pedersen commitments are $Gm_1+Hr_1$ and $Gm_2+Hr_2$.
When adding these two, I got a new Pedersen commitment as $G(m_1+m_2)+H(r_1+r_2)$ with message $m_1+m_2$ and randomness $r_1+r_2$. But... |
I have been reading a paper about accumulators (title of the paper: "Universal Accumulators with Efficient Nonmembership Proofs"). It mentions "auxiliary information" about a function, which I couldn't quite understand. Can anyone explain the term in this context?
|
ChaCha20 also provides 256-bit encryption, i.e, 2^256 possibilities of keys. But ChaCha20 is very fast, I think it provides at most 2^256 multiplied by decrypting time. 256-bit AES provides 254-bit security due to biclique attack, i.e., 2^254 multiplied by decrypting time. Since AES is slower than ChaCha20 (decrypting ... |
The terms "average-case", "worst-case" hardness are quite confusing.
What do they mean when they say certain problems (like lattices)
have an average-case to worst-case relationship? Do they mean there
is a polynomial reduction between two case of the problem? Because
polynomial reductions are of our interest as they ... |
I am wondering whether there are any current challenge problems for Discrete Logarithms.
Specifically in $\mathbb{Z}_p^\ast$ as well as in elliptic curve groups.
It turns out CERTICOM still has some ECC challenges, and it seems 131 bits is the smallest unsolved case. See the link
here.
One concern I have is that given ... |
I am studying TLS handshaking by example a program tlse, which uses libtomcrypt library.I see that in line 5236 (link above) the program call libtomcrypt procedure ecc_ansi_x963_export(context->ecc_dhe, out, &out_len) .I see that the procedure forms a ECC key in the buffer out and add it to client "key_share" extension... |
The section 4.4.1 of the RFC 8446 tells about Transcript-Hash.
My questions about the transcript-hash are:
Must a server hash (a) all own sent messages, enumerate in the section 4.4.1, or (b) own sent and received from client ?
Must a server send the calculated transcript hash in any message separately or the hash is ... |
I always get stuck at those kind of exercises in my Cryptography class. I just don't understand how should I build these scenarios of "sending m1 and m2 and then somehow telling if it was m1 or m2 etc..." attacks. Can someone explain to me in simple terms how can I describe a scenario for this exercise:
"Show that the ... |
This arose from a recent question's comment. Why is translating to Welsh less secure than encrypting the King's English?
|
Good day,
I've a question regarding Gaussian distribution properties over lattices :
Let $\mathcal{L}$ := $ \mathcal{L}(\,b_{1}$,..., $b_{m})$ be a lattice over $\mathbb{R}^{n}$, and $W$ = span($b_{1}$,..,$b_{m}$)$^{\perp}$. define $\pi_{W}$ to be the orthogonal projection onto $W$.
If i sample a vector b from a Gaussi... |
In the steps of “Append the padding bits” in SHA-512 system, the message is padded so that its length is congruent to 896 mod 1024. I'm new to cryptography and I can't figure out the difference between message-length field and message length. I'm not sure what is the correct value of SHA-512 message-length field..?
And... |
I want to ask about the confidence interval in NIST SP 800 22 so I can make sure I got it right. When evaluating the randomness of many binary strings, for example 1000 binary strings. In the NIST SP 800 22 document section 4.2.1, it is recommended to calculate the confidence interval given by the formula: $\hat{p} \pm... |
I'm hoping to get some help regarding an old problem that has eluded me. I'm trying to figure out how the VB6 PRNG was used to generate a byte output from the two byte seed that the Randomize() function provided it. I'm trying to replicate the code in C and seed it with my own 2 bytes, something like 0x12FF.
I'm lookin... |
In the IETF Draft Deterministic ECDSA and EdDSA Signatures with Additional Randomness, methods had been specified to seed RNG deterministically with external input, to securely obtain a nonce for use in signing formula. The external input is variable to mitigate certain side-channel that may occur with fully determinis... |
I am currently writing a paper in my old age for the fun of it. I feel that the enigma machine had gotten a bad wrap for some of its flaws. I decided to write a machine simulation to see if I can correct some of these flaws. The part of the "not being able to encode a character unto itself" isn't as large a flaw as fir... |
As I am studying ordinary (non-supersingular) binary elliptic curves in the Guide to ECC book by Hankerson (Section 3.1, page 81), for point doubling, the equations presented in the book are:
$x_3 = \lambda^2 + \lambda + a = {x_1}^2 + \frac{b}{{x_1}^2}$
$y_3 = {x_1}^2 + (\lambda + 1) x_3 $
$\lambda = x_1 + y_1/x_1$
I h... |
I'm learning provable security, and I'm a bit confused with the concept of reduction.
So, here's my understanding:
to prove a protocol/scheme/generic construction is at some level of security, there are three components: the scheme itself ---> a security proof ---> the scheme achieves a security property.
The security ... |
As learning to be an electronic engineer, my lecturer has requested, based on the original Xtea, to develop the FPGA solution to run 128-bit block size and 128-bit key size cryptography. I have decided to solve it by dividing the 128-bit block into four 32-bit blocks and running as double encryption. I wanted to make s... |
I don't have a deep mathematical background in cryptography. I am reading "The FFX Mode of Operation for Format-Preserving Encryption". Section D says the following.
Why feistel? The authors believe that, for FPE, there is, at present, no serious alternative to
some form of Feistel. The approach benefits from being a ... |
In the book The Design by Rijndael states that the design criteria for the S-box are nonlinearity and algebraic complexity. Can these two criteria be considered as two specific cryptographic properties of the AES S-box? if not is there any way to determine the cryptographic properties of AES S-Box ?
|
I'm designing an authenticated encryption scheme for a noninteractive one-way radio telemetry system. A number of devices in the field send back telemetry to a base station periodically, but no communications are sent from the base station to the devices.
My requirements and threat model are as follows:
The devices ca... |
I'm working in an embedded system that uses TLS v1.2 protocol for network security and it acts as a client.
Now I want to test some TLS security functions that require connecting with a TLS server and see how a client interacts if the server tries to perform unexpected behaviors that can be configured by me. Some of be... |
I am following the procedure described on p. 319 of the fourth edition of Douglas Stinson and (since that edition) Maura Paterson's Cryptography − Theory and Practice (IBSN 978-1-03-247604-9).
The context is recovery of the nonce $k$ in ElGamal signature in $\mathbb Z_p^*$, assuming nonce reuse. We have two message/sig... |
TL;DR: Is encrypting data with AES CBC with random IV + PBKDF2 key using the username as salt safe?
I have searched the internet, but I could not find a proper answer that encompasses the "AES CBC and random IV with PBKDF2 same salt" dilemma.
The scenario
I am developing a client/server/DB system, and my users need to ... |
The notion of security considered here is privacy. Is there a secure two-party protocol does not rely on randomness at all when considering passive adversaries (or active adversaries)? If the answer is no, are there any proofs of this in the literature? I tried to find relevant information, but still got nothing.
|
I'm not sure if anyone explored this area before. Blockcipher encryption definitely fullfills IND-CCA, but what about its inverse? Is there a proof that shows blockcipher decryption is as secure as encryption? Or is there an counter-example? Or it's an open problem?
|
With regard to AES encryption on blocks, the next diagram showcase how does a change in one cell in the block (every cell is a byte) creates a change in encryption for ALL cells:
Now I have the next question, from a network security course:
Say we change the "Mix Columns" stage to be "Rotate Clockwise", that works as ... |
I'm trying to implement AWS Encryption SDK for JavaScript in a browser environment within a React application. When I attempt to construct an instance of the encryption client using buildClient function with CommitmentPolicy.REQUIRE_ENCRYPT_REQUIRE_DECRYPT policy:
const { encrypt } = buildClient(CommitmentPolicy.REQUIR... |
I have some issue to understand the verify round of the KZG polynomial commitment scheme. The following diagram is associated to the scheme. I appreciate any help.
To verify, the verifier should compute the pairing of $e(g^{f(\tau)-f(u)}, g)$ and $e(g^{\tau-u}, g^{q(\tau)})$.
However, to compute these pairings, verifie... |
While designing a crypto system based on existing standards and specifications i find myself questioning some of the accuracy in the current RFC-8037 and IANA specs around Edwards curves, 25519 and ed25519 notation
In RFC8037, they say that the public key in its compressed form (32 bytes) should be represented by X. Bu... |
Is there a simple way if counting the number of $S$-Boxes of length $\ell$ over $\mathbb{F}_{2}$? By $S$-box I mean an $S$-box satisfying the avalanche condition.
I mean it is quite easy to see that for $\ell=2$ the answer is $0$ but I want to know if there is a general formula, specifically for $\ell=3$?
|
I encounter an odd issue when I calculate SHA256 checksums in Javascript. I use the following code:
const hashBuffer = await window.crypto.subtle.digest("SHA-256", arrayBuffer)
const hashArray = Array.from(new Uint8Array(hashBuffer));
const hashHex = hashArray
.map((b) => b.toString(16).padStart(2, "0"))
.join(... |
I was looking at a layman explanation for zero-knowledge proofs in zk-SNARKs here.
The idea there is that if one knows a solution (3) to a question (find a value of x satisfying x^3 + x + 5 = 0), then one can prove this using a circuit to represent the computation and its intermediate variables. Further details on how ... |
I was (trying to) read the following paper: https://eprint.iacr.org/2015/673.pdf
Page 2 says:
A related attack is to replace a point P with P + T, where T lies in a small
subgroup. If the user multiplies by a scalar s, they will get sP + sT instead of
sP, where the difference sT gives away the low-order bits of s. The... |
In one online crash game website (casino betting game), every game has a hash that is made public after the plane crashes and the crash coefficient is supposed to be random. The coefficient can be retrieved using the game hash (so if you know the game hash you know the crash coefficient).
But what I find unclear is tha... |
I have used the threshold version of Paillier encryption without a trusted dealer in an application. I have tested the key generation phase with different security key sizes such as 80, 512, 1024, and 2048 bits.
With each security size, the key generation time is different and unpredictable due to the randomness involv... |
Following up this question
There are 4 parties:
Alice, who needs to prove a posession of some statement $m$, unique to her, say a street address, which is basically a string of some predefined format, to
Bob, who consumes the proof.
an Oracle, who "helps" Alice to prove $m$ by performing some external checks and signi... |
In Regev's paper(the right link now) in Lemma 3.12, can someone explain to me how we get from Eq. (15) to the next one?
(1) We can only have a superposition of finitely many states, how can we manage to store $x\mod\mathcal{P}(L)$? Isn't this set uncountably large?
(2) Afterwards we measure that register and get a $y \... |
Bit based division property is a great method of Integral attack on block ciphers, which was invented by Y. Todo.
According to the paper Bit-Based Division Property and Application to Simon Family (in proceedings of FSE 2016), how does the set $[11110000]$ will propagate bellow sets?
$[11110000]\rightarrow [11110000]; ... |
Can ECDSA signature signing and verification process replaces password hashed based login system?
The title of this question won't be exactly right.
This is a question that I asked long time ago. I would like to ask does the same application or the underlying mechanism still applicable or is still consider secure when ... |
I recently started to learn about Shamir secret sharing and Feldman's VSS Scheme.
I know the concepts But I can't figure out how it works. mostly because many of modulates are with "p" and some of them are with "q". I can't find a good sample that helps me understand it better.
here's the example I am working with:
ass... |
In previous versions of TLS, the choice of the Diffie-Hellman parameters was up to the participants. This resulted in some implementations choosing incorrectly, resulting in vulnerable implementations being deployed. How does TLS 1.3 takes this choice away?
How are the X(g^x mod p) and Y(g^y mod p) values determined wh... |
I want to conduct an anonymous Internet survey (e.g. “What’s your favorite fruit?” with a multiple choice answer) among a given set of people. Double answers by the same participant are not allowed.
I’m looking for a method to conduct this survey using only e-mail and a web page (and maybe trusted software) in a way s... |
I've been navigating through many of StackExchange's history questions about point at infinity, and there's something that still doesn't "click" for me.
Let me share my understanding (and its logic) and maybe become apparent where I fail.
Let's say I have an elliptic curve equation, particularly a Twisted Edwards Curve... |
I'm reading about the lecture of Yevgeniy Dodis. In his lecture 14, section 2.3.2, gives a commitment construction based on CRHF, but the proof of hiding is high-level. I want to know the rigorous proof that why even subject to $u(x)=m$, the still leaves distribution of $u$ look almost uniform to the adversary independ... |
Consider a verification equation $ e(\Delta,\tilde{G}) = e(W_x,x\tilde{G}+pk_{acc})$ from a pairing based accumulator which uses the value $x$ and the corresponding witness $W_x$ to verify that a value $x$ is accumulated in the accumulator $\Delta$.
For anonymous credential system for multishow unlinkability, we ofte... |
I asked this question on StackOverflow but it seems like it's more appropriate for this Crypto community.
I am using the browser built in SubtleCrypto library in javascript to generate public and private keys as such:
let keyPair = await crypto.subtle.generateKey(
{
name: "ECDSA",
namedCurve: "P-521... |
Are you aware of papers proposing secure multiparty computation protocols for stable matching problems such as Stable Roommates and Stable Marriage problems?
Specifically, I would like the ranking of each party to be kept private and either reveal the whole output to everybody (all the pairings) or just reveal each pai... |
I am reading the Lightweight Introduction to Lattices and it is a problem Challenge 8 that makes me quite struggle. Basically, the problem give us an encrypted version of a message using Merkle-Hellman Knapsack Cryptosystem. Each letter, before being encrypted, is converted into ASCII bytes (e.g. c: 01100011). Each num... |
I understand that we need 2-to-power cyclotomic ring to show that the solving decision RLWE is as hard as solving search RLWE.
Is there any chance to prove it without 'cyclotomic' property?
For example, in NTRU prime, using Z[x]/(x^p-x-1), can we show worst case reduction from LWE?
|
I'm trying to create a zk-proof of a neural network in https://github.com/berendjan/zk-neural-network using ZoKrates and PyTorch.
The steps to reproduce are in the README.md
However, when computing the witness I run into errors
time ./run.sh
Compiling network.zok
Compiled code written to 'out'
Number of constraints: ... |
There are two papers that propose oblivious transfer protocols, both claiming to be universally composable (UC). The first protocol is more complex, and I am convinced that it is indeed UC. The second protocol is simple, but reminds me of the so-called "simplest OT protocol" of Chou and Orlandi, which is well-known to ... |
I found information, that it is possible to construct a hash and signature that look valid if the hash is not computed within the contract itself (we are talking about ECDSA/ecrecover here).
So, the task is to construct a hash + v, r, s that would resolve to a particular address using ecrecover(). I have access to seve... |
Imagine this scenario:
On a particular PC is a service that provides cryptographic functions -- in particular AES-CBC and ECC (ECIES/ECDSA).
The service provides access to a single key stored in an HSM -- the key itself is never visible to any software on the PC (including the service itself).
Copying the service soft... |
I'm not sure if this is a good place to ask, but I have some issues with using plonky2 to make some proof.
In particular, I want to prove that a private element is part of a set (i.e. $x \in X$), and that this same element is the primitive of a hash function (i.e $\operatorname{SHA}256(x) = h$). The set $X$ and the has... |
In lemma4.5, of PlonK: Permutations over Lagrange-bases for
Oecumenical Noninteractive arguments of
Knowledge
they claim that we can construct a polynomial protocol $P^*$ with an $S$-ranged polynomial protocol $P$. However, in my opinion, I think it constructed $P$ using $P^*$ in the proof.
Specifically, in the last st... |
This is a followup to my recent question Discrete Logarithm Challenges and Records.
I am interested in confirming my understandings from the answer to that question, stated below:
For a discrete logarithm problem in a generic group of size $N$ with no special algebraic structure, the best known attack is the Pollard's... |
In the NIST 800-56A rev3 "Recommendation for Pair-Wise Key-Establishment Schemes Using Discrete Logarithm Cryptography" in section 6.1.1.2 "(Cofactor) Full Unified Model, C(2e, 2s, ECC CDH) Scheme" the shared secret is calculated as follows:
Party U Calculates:
$Z_s = d_{s,U} Q_{s,V}$
$Z_e = d_{e,U} Q_{e,V}$
$Z = Z_s ... |
There is a random scalar seed $s$ which we may call a master secret.
There are 2 public strings or scalars: $m1, m2$ and 2 corresponding EC keypairs: $a, A=a*G$ and $b, B=b*G$
$a$ and $b$ are somehow securely derived from $(s, m1)$ and $(s, m2)$ respectfully.
It might be $a = HKDF(s, m1)$ or $a = s + m1$, or some hash,... |
Let's say there's Alice and Bob.
Let Alice and Bob agree on a message $M_1$, a tag $T_1$, and a function $HMAC$.
Alice proves to Bob that she knows a key $K$ such that $T_1 = HMAC(M_1, K)$ without revealing what $K$ is, using a zero knowledge proof.
Alice sends Bob some cryptographic object $MysteryBox$.
Alice dies.
W... |
This is a rather simple question, but answers are nowhere to be found. Are there any variants of Poly-n hashing algorithms which provide bigger outputs (like 32 instead of 16 bytes)? Or, is there any research which discusses the variability of the constant $2^{130}-5$, why this number is special or whether there are ot... |
So originally a puzzle was given out to a community i'm a part of and what was given was this.
. .. . ... . . . . . . . ... . .. . . . . . .. . ... . . . . . .... . .. . . . . . .. .. .. . . . . . .. . . . . .. ..... . . . . . .. .. ..... . . . . . .. . . . . . . . .... . . . . . . . . . . . . . .... . . . . . .. . . .... |
I'm working on solving a encryption task, and I'm a bit stuck. I want to clarify that I'm only seeking hints and not direct answers since I want to solve it myself. The goal is to solve it on my own; otherwise, it wouldn't make sense. Therefore, I'm just looking for hints to help me progress from where I'm stuck or any... |
Let's start with what got me wondering about this issue:
It's a curious construction, that while most digital signature schemes come from public-key encryption (Impagliazzo's cryptomania), there are constructions like SPHINCS that construct secure signature out of a hash function (Impagliazzo's minicrypt).
Now there ex... |
I encountered a question while reading an article. My understanding is that fully homomorphic encryption supports ciphertext addition and multiplication. Why does the basic protocol given in this article include ciphertext subtracted by plaintext?
|
Let E be an elliptic curve of prime order n. If we assume that Alice and Bob both know a scalar value z, is there a known zero-knowledge protocol (ideally a Sigma protocol) that allows Bob to convince Alice that he knows some point R such that zR satisfies some equation?
The context of this is as follows. I've recently... |
I'm learning OQS OpenSSL and I'd like to create a certificate with dilithium in C, using liboqs and OQS OpenSSL. This is my code (based on https://stackoverflow.com/questions/256405/programmatically-create-x509-certificate-using-openssl and a lite bit of chagpt):
#include <stdio.h>
#include <stdlib.h>
#include <string.... |
I am looking for references for the most basic secret sharing and MPC arithmetic algorithms for generic rings or prime fields.
Problem:
Suppose there are $m$ parties $P_1, \ldots, P_m$ which wish to do arithmetic over a ring.
They hold some secret shared values $[x], [y]$ and they wish to compute $[x+y]$ and $[xy]$.
... |
I have been wondering if sending audio fragments over a phone call would be considered a form of cryptology.
Let's say that you own two mobile phones and say that one of your phones is on the Verizon network and the other is on the AT&T network. You have a friend who also owns two mobile phones. Say that one of his pho... |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.