In practice and with respect to security, no, mathematically, yes. If you have a private key (N, D), there is algebraically an infinite number of solutions to the equation 1 = E*D (mod Phi(N)). However, if you make two such solutions (E, N) and (E’, N) that both satisfy the equation public, you will have … Read more
In RSA you should use the public key for encryption and the private key for decryption. Your sample code uses for encryption and decryption the public key – this can not work. Hence in the decryption part you should initialize the cipher this way: cipher1.init(Cipher.DECRYPT_MODE, privateKey); Furthermor your code has a second significant bug: You … Read more
I just ran into this issue, on the gpg CLI in Arch Linux. I needed to kill the existing “gpg-agent” process, then everything was back to normal ( a new gpg-agent should auto-launch when you invoke the gpg command, again; …). edit: if the process fails to reload (e.g. within a minute), execute gpg-agent in … Read more
Your teacher gave you: Public Key: (10142789312725007, 5) which means n = 10142789312725007 e = 5 where n is the modulus and e is the public exponent. In addition, you’re given Private Key: (10142789312725007, 8114231289041741) meaning that d = 8114231289041741 where d is the decryption exponent that should remain secret. You can “break” RSA by … Read more
id_rsa.pub and id_dsa.pub are the public keys for id_rsa and id_dsa. If you are asking in relation to SSH, id_rsa is an RSA key and can be used with the SSH protocol 1 or 2, whereas id_dsa is a DSA key and can only be used with SSH protocol 2. Both are very secure, but … Read more
Following are setup steps for OpenSSH shipped with Windows 10 v.1803 (April 2018 update. See comments to this post, it might not work with 1809). Server setup (elevated powershell): Install OpenSSH server: Add-WindowsCapability -Online -Name OpenSSH.Server~~~~0.0.1.0. Start agent and sshd services: Start-Service ssh-agent; Start-Service sshd (this will generate host keys and default configuration automatically in … Read more
openssl rsa -in privkey.pem -pubout > key.pub That writes the public key to key.pub
I had the same issue after copying my key pair from one machine to another. The solution for me was the set the trust level of the keys: gpg –edit-key <KEY_ID> gpg> trust You will be asked to select the trust level from the following: 1 = I don’t know or won’t say 2 = … Read more
You can’t just change the delimiters from —- BEGIN SSH2 PUBLIC KEY —- to —–BEGIN RSA PUBLIC KEY—– and expect that it will be sufficient to convert from one format to another (which is what you’ve done in your example). This article has a good explanation about both formats. What you get in an RSA … Read more