What is the relationship between the public and private keys generated by SSH and the host that generated them? What is the basis for their generation? How can I verify their authenticity?

一沙一世

What is the relationship between the public and private keys generated by SSH and the host that generated them? What is the basis for their generation? How can I verify their authenticity? [Copy link]

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What is the relationship between the public and private keys generated by SSH and the host that generated them? What is the basis for the generation? How to verify the authenticity? How to verify whether the public and private keys are a matching pair?

bigbat

The public key and private key have nothing to do with whether they are generated by SSH. As long as the algorithm supported by SSH is used, SSH can use it. As long as the algorithm is the same, the public key and private key are the same regardless of the software. You can also use other software to generate a "public key and private key pair" and then import it into the SSH certificate library. Then SSH can be used. For example, the key pair obtained by the CA organization can also be used by SSH. How to verify: You can use any encryption and decryption software. Only fixed key pairs can be used for asymmetric encryption

jimtien

It has nothing to do with the host. One key has one lock, and it has nothing to do with which room it is used in.

To generate the public key and private key, let's learn about the RSA algorithm. The basic principle is to randomly find two prime numbers a and b that are large enough, and tell you the product axb. You cannot factorize a and b. Use the product to generate the public key, and the two prime numbers to input the private key (roughly like this)

se7ens

jimtien posted on 2022-5-19 11:26 It has nothing to do with the host. One key and one lock have nothing to do with which room it is used in. The generation of public and private keys, understand the RSA algorithm, the basic principle...

The public key is the lock and the private key is the key.

The public key is public, but the private key is only held by the user.

Since the public key is visible during transmission, how can the private key be transmitted to the other party so that they can decrypt it?

jimtien

Public key encryption, private key decryption; private key signature, public key verification