Questions tagged [dsa]
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39 questions
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Generating a DER-encoded DSA public key of a particular file size
I am reverse engineering a binary that contains a raw, DER-encoded X.509 certificate containing a DSA public key. I want to replace this certificate with one that I have generated so that I have ...
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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 ...
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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 ...
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924
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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 ...
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Is it safe if SSH and HTTPS server share the same RSA/DSA keys?
I'm configuring an ssh server for an embedded device. This device already has an x.509 certificate and a pair of public key and private keys stored in it that is used for its HTTPS server. Is it safe ...
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What are the differences between the RSA, DSA, and ECDSA keys that SSH uses?
In my /etc/ssh/ directory, I can see three keys which contains three different types of ssh keys:
-rw------- 1 root root 607 Oct 4 22:43 ssh_host_dsa_key
-rw-r--r-- 1 root root 623 Oct 4 22:43 ...
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726
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TLS - DHE_DSS: How does client know public DSS-server key?
I wonder where the public server key g^x for DSS authentication is communicated to the client when a DHE_DSS cipher suite is used in TLS 1.2. Precisely:
A DSS certificate contains crypto parameters (...
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645
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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 ...
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5
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Impact analysis of CVE-2016-1000341 affecting BouncyCastle
I am analyzing the impact of CVE-2016-1000341 having CVSS score 7.5 and description "DSA signature generation vulnerable to timing attack. Where timings can be closely observed for the generation of ...
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DSA/Digital Signature Algorithm, how is it applied in web applications? LAYMAN explanation please! [closed]
I understand how the digital signature algorithm works. However all the explanations and examples are only about Bob sending a message to Alice.
What i want to know is how digital signature is used ...
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Website uses an unsupported protocol. ERR_SSL_VERSION_OR_CIPHER_MISMATCH
I just installed a new wildcard certificate on my Ubuntu server (there was a single certificate installed before). I modified /etc/apache2/sites-available/000-default.conf which is for one specific ...
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Does SSH support DSA with 2048 bit keys?
In FIPS 186-1 and 186-2 L could be any number between 512 and 1024 (inclusive) that was a multiple of 64. N was fixed at 160.
FIPS 186-3 changed it so that L and N could be any combination of the ...
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How do I sign a short text message with ~/.ssh/id_{dsa,ecdsa,ed25519}?
There are already a number of questions about reusing SSH keys for something else:
Converting keys between openssl and openssh
How to use public key in ~/.ssh for asymmetrical encryption with OpenSSL
...
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Found DSA and RSA private keys hard-coded in a file during penetration testing. How to use them for SSH authentication?
We are performing a penetration test as part of a study where the hardware unit listens for connection over FTP, SSH, and Telnet. All of these are password-protected. The hardware unit must first be ...
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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 "...
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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 ...
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Why OpenSSH deprecated DSA keys
There was a question RSA vs. DSA for SSH authentication keys asking which key is better. Basically all answers were more in a favour of RSA over DSA but didn't really tell that DSA would be somehow ...
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838
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Is it possible to have an RSA authentication subkey with a DSA master key?
My key setup is as follows:
sec dsa3072/CA72E53A
created: 2013-05-12 expires: never usage: SCA
trust: ultimate validity: ultimate
The following key was revoked on 2016-01-13 ...
- 133
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561
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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, ...
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Generation of the primes p,q and g for DSA using an Hash Function in OpenSSL
We can generate primes p,q and g for DSA in OpenSSL by using command:
openssl dsaparam -text -out dsaparam.pem 1024
Is it possible to generate primes p , q and g using an Hash Function in OpenSSL ...
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12
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Should DSA keys be considered deprecated?
The gist of openssh deprecates dss-keys appears to be:
"In light of recently discovered vulnerabilities openssh deprecates DSA keys."
Does this mean I should generally consider DSA keys deprecated?...
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Significance of the difference between DSA and RSA in signature verifying speed
I have run openssl speed and the output on my CPU for longest available DSA key size, which is 2048 bits:
sign verify sign/s verify/s
rsa 2048 bits 0.029185s 0....
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GPG: Can't encrypt DSA 3072 keys
I would like to ask this question as I'm not the first person which has
this behavior.
I'm trying to encrypt a simple message using GnuPG using a public key I've
received from a friend, he's using ...
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RSA vs DSA Digital Signature Message Digest Recovery
I'm learning about signatures using RSA and DSA, I've come across this little fact:
RSA can recover the message digest from the signature, whereas in DSA this isn’t possible – you have to have the ...
- 2,617
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RSA vs DSA working methodolgy?
I have looked for various answers but I am being confused on how does RSA can be used for both Digital Signatures and Encryption/Decryption like in "TLS_DHE_RSA_..." or "TLS_RSA_.." cipher suite ...
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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 ...
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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 ...
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New PGP key: RSA/RSA or DSA/Elgamal?
I wanted to create a new PGP key using GPG Keychain Access on my Mac. One of the options was to choose keytype:
RSA and RSA
DSA and Elgamal
RSA (Sign only)
DSA (Sign only)
I found this Superuser ...
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openssl ECDHE-RSA... cipher suite selected while using RSA server cert and ECDSA client cert
The scene:
s_server using RSA certificate.
s_client using ECC-ECDSA certificate.
Client authentication is required (option -Verify set on s_server)
Cipher-suite selected after handshake is ECDHE-...
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768
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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".
...
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Are DSA keys breakable?
Are the DSA keys breakable? If so, what is the maximum key size that is breakable with the latest technology ?
Why are DSA keys not used during authentication?
Can we use DSA keys for encryption?
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Are RSA 2048, ECDSA, and the SHA uncrackable in the sense that AES-256 is uncrackable?
The answer
https://security.stackexchange.com/a/25392
has seemingly shown that AES-256 will not be directly cracked for at least the next 200 years (unless we manage to harvest the energy output of ...
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Why are DSA keys referred to as DSS keys when used with SSH?
When I generate a DSA key with ssh-keygen -t dsa, the resulting public key will begin with ssh-dss.
How come? Why not ssh-dsa?
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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 ...
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DSA Generates different signatures with the same data [closed]
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 ...
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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 ...
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461
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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 ...
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915
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Does DSA need padding?
So I read on wikipedia that digital signatures need padding (like PSS) and I know this is true for RSA.
But now I ask myself does DSA also need padding?
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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 ...
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