an asymmetric (e.g. public-key) cryptosystem, based on modular exponentiation with big exponents and modulus. RSA can be used both for signature and encryption.
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61 views
Is there a big RSA Data Set
Is there a big dataset containing RSA public $(n,e)$ and private keys $d$ and primes $p,q$ where $n = p.q$ ?
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2answers
278 views
Are there any standards of multi-prime RSA key generation?
FIPS 186-3 specifies a method to generate DSA parameters.
Is there anything similar (official standard or widely-accepted recommendation) that shows how to generate the primes for multi-prime RSA?
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2answers
207 views
RSA blind signatures in practice
Hi I have a problem with moving my blind signature implementation from educational (textbook RSA) to more practical (padded RSA) side.
David Chaums paper gives a following figure:
$r$ - blinding ...
18
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2answers
865 views
How are primes generated for RSA?
As I understand it, the RSA algorithm is based on finding two large primes (p and q) and multiplying them. The security aspect is based on the fact that it's difficult to factor it back into p and q. ...
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1answer
136 views
using Post-quantum asymmetric ciphers instead of RSA
We can't trust RSA to encrypt our Emails so what is best post-quantum cryptography system as alternative for RSA which provide good security and don't be breakable? because McEliece cryptosystem looks ...
2
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1answer
110 views
RSA Key generation Public exponent too big
I'm currently writing a paper about RSA (a self-chosen subject).
I'm writing about the key-generation in RSA, and I have problem finding the public exponent e.
I have chosen p = 61 and q = 53.
Then ...
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0answers
77 views
Factorize RSA knowing several N and E
I did a CRT challenge yesterday and there`s one problem I was unable to solve, probably due to my lack of understanding advanced crypto math.
It`s about RSA. There are ten given pairs of N and E ...
2
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1answer
110 views
RSA Without Padding?
I've been looking at the weakness with plain/textbook RSA, where the same message is encrypted and sent to multiple destinations. In this case, it is possible to recover the message.
Given that an ...
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1answer
101 views
Does RSA-OEAP have integrity and authenticity properties?
RSA-OAEP is IND-CCA2 secure (indistinguishable under an adaptive chosen ciphertext attack). Does it also have the INT-CTXT (integrity of ciphertext) and INT-PTXT (integrity of plaintext) properties?
...
4
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1answer
260 views
Get RSA PlainText without Knowing Private Key
If I have an algorithm,RSA-Crack(), that, for a given RSA public key (n,e), is able to decrypt 1% of the messages encrypted with that key (without knowledge of the corresponding private key).Can there ...
4
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1answer
153 views
In RSA encryption, does the value of e need to be random?
I am a novice programmer and am just finishing up an RSA encryption program that I am writing for practice. Currently I have the program generate a relatively small random value for the public key e. ...
5
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1answer
376 views
RSA-OAEP Input Parameters
When creating padding for RSA using OAEP, a message is prepared as follows:
Hash(Input Parameter) || Zeros || 1 || Message
My question is, what should the Input ...
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1answer
180 views
Weakness in using only one RSA key pair for two-way communication?
In Alice/Bob/Cindy terms (EDIT: and with a little more detail):
Alice and Bob have each securely obtained one key of an RSA keypair from a trusted third party. Alice has one key ($e$ and $n$), Bob ...
2
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1answer
236 views
Constructing RSA private key, given public key
As part of a puzzle I was given an RSA 256-bit public key and an encrypted message.
The key itself is very weak, having exponent e = 65537 and modulus N = ...
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0answers
78 views
Actual weakness RSA [closed]
I need modern trends analysis RSA. Hinek books "Cryptanalys RSA and Yan "Cryptanalytic RSA" have been read. What else?
2
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3answers
621 views
Is it safer to encrypt twice with RSA?
I wonder if it's safer to encrypt a plain text with RSA twice than it is to encrypt it just once. It should make a big difference if you assume that the two private keys are different, and that the ...
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4answers
557 views
Is Wiener's attack on RSA extendable to larger keys with low hamming weight?
Using small private exponents with RSA improves performance.
However, it has been shown (Wiener, 1990) that if $\log d \leq \frac14 \log N$, the private exponent $d$ can be reconstructed from the ...
4
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1answer
128 views
Why does OAEP have 2 rounds with 2 random oracles?
I strive into understanding why OAEP has two rounds of computations and not just one. I.e: Wouldn't it be safe to hash the random number r and XOR it with the original message?What security risks if ...
2
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0answers
104 views
Ring Signature - paper/code difference in trying to solve inverse trap door function?
there is a paper on ring signatures and a python implementation of it here.
The Step 4 in the paper describes $y_s = v =C_k,_v(y_1, y_2, ... y_r)$ for all $1 \leq i \leq r$ where $i \neq s$. The ...
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2answers
120 views
Breaking RSA, given a special kind of oracle that decrypts related ciphertexts for us
Let $c=E^{RSA}_{e}(w)$ be the ciphertext belonging to the plaintext $w$ if an $RSA$ system is used. Assume that the public exponent $e$ satisfies $e \le 10$. Furthermore, assume there is an oracle ...
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1answer
167 views
What is a trapdoor permutation?
Can anyone explain to me what a trapdoor one-way permutation is? Is RSA a trapdoor one-way permutation?
Context: I was reading about ring signatures. On page 560, it describes steps to ...
6
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4answers
408 views
Is an RSA variant with public exponent $e=f+(p-1)\cdot(q-1)$ safe (for $f$ random in some small interval)?
Alice is going to use some existing RSA scheme (employing industry-standard signature or/and encryption with proper padding), which she can't change, or influence beyond her choice of key. In this ...
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2answers
357 views
RSA and prime difference
It is known that the two prime factors $p$ and $q$ of an RSA modulus $n$ should not be too close to each other, otherwise an attacker may factor the modulus. In other words, $\Delta = \left| p - q ...
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2answers
820 views
Can two different pairs of RSA key have the same modulus?
Can $n=pq$ be part of two different pairs of RSA keys?
If such keys exist, say $(e_1,n)$ and $(e_2,n)$, how are they related?
What will be the security concerns for the two users?
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1answer
140 views
Why do we need in RSA the modulus to be product of 2 primes?
I think I roughly understand how the RSA alorithm is working.
However, I don't understand why we need the $N$, which we use as a modulus, to be $pq$ for some large primes $p, q$.
I vaguely know it ...
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1answer
506 views
ABC Conjecture's Impact on RSA Encryption
A recent proof of the ABC Conjecture has been released by one Shinichi Mochizuki. Now, I'm not well versed in mathematics but it would appear that this proof implies that finding prime factors could ...
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3answers
464 views
Would the ability to efficiently find Discrete Logs have any impact on the security of RSA?
This answer makes the claim that the Discrete Log problem and RSA are independent from a security perspective.
RSA labs makes a similar statement:
The discrete logarithm problem bears the same ...
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2answers
124 views
RSA keys finding when messages are known
I have this situation, where, in a game, people send messages to each other (game moves etc...) These messages need to be encrypted, and should only be readable by the destination person. I am using ...
3
votes
1answer
172 views
What's the main difference between Pohlig-Hellman and RSA?
Both Pohlig-Hellman and RSA perform encryption and decryption by exponentiation modulo some integer ($p$ prime for PH, $n$ composite for RSA). They both use a key $e$ as the exponent to encrypt a ...
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1answer
109 views
RSA encryption input range - plaintexts that map to ciphertexts?
According to the wiki article on the RSA encryption function, the valid range of input $m$ is $0 \leq m \lt n$. However I have found that the following values of $m$ always return themselves when ...
6
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2answers
2k views
What's the fundamental difference between Diffie-Hellman and RSA?
What is the difference in the purpose of DH and RSA? Aren't they both public-key encryption?
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1answer
164 views
What is the strength of unpadded RSA?
I would like to use unpadded RSA for homomorphic encryption in a toy P2P game, for things like fair coin flips and shuffling.
How many bits of security does unpadded RSA have, in relation to its key ...
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1answer
221 views
is this RSA private key valid?
is this RSA private key valid?
First, here's the RSA private key in question:
...
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2answers
466 views
Is RSASSA-PKCS1-v1_5 a good signature scheme for new systems?
Is RSASSA-PKCS1-v1_5 a good signature scheme to recommend that people use in new systems? Is it believed to be secure and represent the state-of-the-art in RSA-based signatures?
I understand that ...
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2answers
481 views
Why RSA can't handle numbers above 76?
I'm going to encrypt the characters Zhu, and decrypt them using RSA. I'm using the public key $\{e, n\}$ and private key $\{d, n\}$. The values of $e$, $d$ and $p$ ...
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3answers
336 views
How do ciphers change plaintext into numeric digits for computing?
For example, in RSA, we use this for encryption: $ciphertext = (m^e \mod n)$ and for decryption.
If our message is "hello world", then what number do we have to ...
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1answer
88 views
modulus condition [closed]
In RSA algorithm, the modulus $n$ should be chosen based on the below condition
$2^{8(k-1)} \leqslant n < 2^{8k}$
Where $k$ is the byte length of the modulus $n$.
for this condition I want the ...
2
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1answer
278 views
What is the harm if I publish an encrypted RSA private key publicly?
What is the harm if I publish an encrypted RSA private key publicly? Or in this case, what is the harm if I publish many thousands or millions of them?
Assuming that the private key is encrypted ...
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2answers
66 views
find solutions that solve the equations
I am implementing a timing attack on RSA for school and I need to generate two sets of messages $Y$ and $Z$ for which holds:
$ (Y^d \mod N) \cdot Y < N $ and
$ (Z^d \mod N) \cdot Z > N $
where ...
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4answers
1k views
Encrypting small values with RSA private key
I'm looking for best practices when it comes to encrypting small (< 128 bytes) amounts of data with the RSA private key. Signing it would make the resulting payload too large.
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4answers
1k views
Why is padding used for RSA encryption given that it is not a block cipher?
In AES we use some padded bytes at end of message to fit 128/256
byte blocks. But as RSA is not a block cipher why is padding used?
Can the message size be any byte length (is the encrypting agent
...
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1answer
162 views
RSA 1024bit decryption performance
i want to know how many RSA 1024 bit long key decryption can a regular pentium4 computer do per second ? how to calculate RSA performance and determine its remaining time ?
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2answers
361 views
Homomorphic cryptosystems in RSA
Hopefully Crypto can help me understand homomorphic cryptosystems.
I'm designing a high score server for a game I made, and because of facets in the language i'm using, the player would be able to ...
4
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1answer
1k views
Common modulus attack on RSA when the 2 public exponents differ by a single bit
This is an exam question an i have no idea how to recover the message m.
John wants to send an encrypted message to mary who has a pair of RSA keys, However, John does not know Mary's public key and ...
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3answers
349 views
What is the length of an RSA signature?
Is it the same as the bits of the key (So a 2048 bit system will yield a 2048 bit signature)? At most as the key? Or something else entirely?
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1answer
50 views
Design question for a service that signs messages on behalf of a user
I'm working on a messaging service that lets users author messages and have them signed with an RSA key. The key is used for identity purposes only and can be revoked, so compromising the private key ...
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2answers
809 views
Secure private key storage
I'm developing application in Java that has to store RSA keys in software for foreseeable future (that is, at least 10 years).
The two most common standards of storing private keys are PKCS12 and JKS ...
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1answer
78 views
inverse of 985 mod(φ60131)
Alright Ive been working on this one for a while
I found φ(60131) to be 97294
½(60131+60131(5)^.5) = 97294
then I worked through the GCD
...
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1answer
260 views
How to jusify {e,n} is a valid RSA public key?
I have a two set of key {36,77} and {50,117},
How can validate if it is a valid RSA public keys?
Is there any simple method?
6
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2answers
271 views
What is the key strength reduction encrypting only 160 bits of data using RSA1024 for signatures
I am attempting to determine the strength of an incorrectly implemented 1024 bit RSA signature scheme. The weakness in the implementation is that the padding data lacks random numbers. As a result, ...
