How to check the Public Key Algorithm used for a given gpg key (ie: RSA vs DSA) - Michael Altfield's Tech Blog (2024)

FAQs

How to check public key in GPG? ›

Open Terminal . Use the gpg --list-secret-keys --keyid-format=long command to list the long form of the GPG keys for which you have both a public and private key. A private key is required for signing commits or tags.

Public Key Cryptography (asymmetric) uses encryption algorithms such as RSA and Elliptic Curve Cryptography (ECC) to create the public and private keys.

➢ To create an RSA public/private key pair, here are the basic steps: 1- Choose two prime numbers, p and q such that p ≠ q . 2- Calculate the modulus, n = p × q. 3- Calcuate ϕ( n ) = ( p – 1 ) × ( q – 1 ). 4- Select integer e such that gcd (ϕ( n ), e) = 1 and 1 < e < ϕ( n ).

RSA is a popular and secure cryptographic algorithm that encrypts and decrypts data. It provides a secure method for transmitting sensitive data over the Internet. While RSA has some vulnerabilities, it is still utilized for various applications, like digital signatures to authenticate the source of a message.

RSA and ElGamal, the two public-key cryptosystems that we will examine, are both based upon number-theoretic problems. RSA is based upon the fact that it is easy to multiply together two large primes but it is hard to factor a large integer.

The Rivest-Sharmir-Adleman(RSA) algorithm is the cryptography system that is used for public key cryptography, which is commonly used when sending secure and sensitive data over an insecure network like the internet.

Public key cryptography is a method of encrypting or signing data with two different keys and making one of the keys, the public key, available for anyone to use. The other key is known as the private key. Data encrypted with the public key can only be decrypted with the private key.

To decrypt an RSA ciphertext given the private key (d), ciphertext (c), and the public exponent (e), you can use the following steps: Compute the modulus (n) from the private and public keys using the equation n = p * q, where p and q are prime numbers and d is the private exponent.

GnuPG uses public-key cryptography so that users may communicate securely. In a public-key system, each user has a pair of keys consisting of a private key and a public key. A user's private key is kept secret; it need never be revealed. The public key may be given to anyone with whom the user wants to communicate.

Export Your Public Key

Send the public-key. gpg file to the recipient in an email or copy and paste the contents of the public-key. gpg file. The recipient should import the public key and validate it in order to use it to decrypt a message sent by you.

How do I get my public key from my GPG Keychain? ›

To export your public key, select your key in GPG Keychain Access and then click Export in the menu. Do not select “Allow secret key export”; your secret key should never be given to anybody. Click save to export your public key as an asc file.