IT Security Stack Exchange
IT Security Stack Exchange

Questions tagged [dsa]

39 questions
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Does public key encryption/decryption speed actually matter?

There have been wars fought over RSA, DSA, and I'm sure other public key encryption algorithms, and usually the arguments are "Algorithm A is faster to encode, but algorithm B is faster to decode". However, from what I understand, the slow…
IQAndreas
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DSA Generates different signatures with the same data

I'm using the example given in msdn article about the DSACryptoServiceProvider Class. The problem is that I get a different signature each time I run the code. I tried OpenSSL and didn't get this problem but I need to work with…
Ibrahim.I
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Was DSA invented from RSA?

I'm wondering if the two algorithms are similar and whether DSA was really just based off RSA? Is DSA based on RSA and public key encryption? If so how does DSA introduce signing and makes it different from RSA?
pandoragami
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What will be the key size for rsa, ecdhe and ecdsa from the cipher suite given?

From the cipher suites tls_rsa_with_aes_128_cbc_sha256 and tls_ecdhe_ecdsa_with_aes_128_cbc_sha256 how do I know what will be the RSA , ECDHE, and ECDSA key support in IBM cloud Watson? here is the link to IBM cipher suites support
wanglen soram
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Is the `ssh-agent`'s DSA signature deterministic?

In my hopes to use ssh-agent to generate a signature as password I implicitly assumed a deterministic signature. DSA is however supposed to take random value k for signing. However that randomness is merely required for preventing attackers from…
Tobias Kienzler
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Should I stop using DSA key algorithm self-signed certificates in production in favor of RSA Certificates?

We use a self-signed certificate with DSA key algorithm (and RSA signature algorithm) for securing a Kafka cluster in production. The access to the Kafka servers is already limited (by firewall) by allowing access only to specific IP subnets. The…
avm
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Can an attacker replace the hash of a download, a download, and the public key?

I have a question about DSA and GPG. Suppose you are trying to verify a downloaded file is 'legit' (i.e., no malicious code and it is the intended file). I'll just use Ubuntu's 16.04 LTS ISO image as an example. Following through the instructions, I…
coolboyjules
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RSA-1024 vs. DSA-1024: Claim DSA SSH key is much faster to brute force

Does the brute force speed vary significantly between 1024-bit RSA and DSA SSH keys? DSA like gpu keypairs are probably DSA/Elgamal? (Can't find docs) EDIT: The reason I ask is an instructor that "has been involved with computer security for 10+…
StackAbstraction
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TLS DSA signature inputs

Each TLS1.0 implementation must support the use of the TLS_DHE_DSS_WITH_3DES_EDE_CBC_SHA cipher suite. This cipher suite dictates that the server must send a ServerKeyExchange message with the following structures: struct { opaque…
evgeni tsvetanov
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Why is DSA is faster than RSA for signature generation but slower for validation?

Almost on every post comparing DSA and RSA, I see a point brought up: DSA is faster for signature generation, but slower for validation. I wonder why this is? For example, in DSA, to sign something, you have to do the same mod_pow as RSA, but then…
Chin
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Rest WebService with signed requests in Java

I'm currently implementing a rest web service with Spring+Java+Tomcat and a cmd client to access it. The most important requirement is to restrict the usage to authenticated users - encryption isn't that important. Because I can't guarantee that…
Peter Clause
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Any way to revoke old key pair?

There is a many-year-old 1024 DSA key in the public keyservers under my name. There is a 2048 ELG-E subkey for it. I didn't create these keys, they were created for me by a former employer without my consent. I don't have the private key and it…
RichardX
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why are the first few characters of a DSA Private Key similar?

I noticed most DSA private keys often start with the same few characters, MIIBvAIBAAKBgQD . For example, generate a private key on Ubuntu, by running: ssh-keygen -t dsa -N '' -f /tmp/id_dsa This results in a private key file that begins with…
JamesThomasMoon
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Using secp256k1 and ECDSA with IKE

I just tried using an IKE daemon and EC certificates. I used the secp256k1 curve for key generation. The daemon claims signature scheme ECDSA-256 not supported by private key Now I am wondering if that is due to incompatibilities in the IKE daemon…
fr00tyl00p
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How can we ensure non-repudiation without a personal certificate (eg. using ID authentication)

I need a help to understand some specific points about non-repudiation, nonetheless I implemented some authentication methods: Digital Signature Authentication; CHAP (Challenge Authentication Protocol) Zero-knowledge password proof Let's imagine a…
Maf
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