I have to generate two keys (private and public) to encrypt a text with the public and let the user with the private key decrypt the text. How to create a pair private/public keys using Node.js crypto? Ask Question Asked 8 years. What if I need OpenSSH (ssh-rsa) public key? Is there a native js way to do, without 3rd party modules. Public key cryptography uses a public key to encrypt a piece of data, and then the recipient uses the private key to decrypt the data. The public and private keys are known as a key pair.

Create Rsa Key Pair

How to Create a Public/Private Key Pair

The standard procedure for creating a Secure Shell public/private key pair follows. For information on additional options, see ssh-keygen(1).

1. Start the key generation program.

2. Enter the path to the file that will hold the key.

   By default, the file name id_rsa, which represents an RSA v2 key, appears in parentheses. You can select this file by pressing Return. Or, you can type an alternative filename.

   The public key name is created automatically and the string .pub is appended to the private key name.

3. Enter a passphrase for using your key.

   This passphrase is used for encrypting your private key. A good passphrase is 10–30 characters long, mixes alphabetic and numeric characters, and avoids simple English prose and English names. A null entry means no passphrase is used, but this entry is strongly discouragedfor user accounts. Note that the passphrase is not displayed when you type it in.

4. Re-enter the passphrase to confirm it.

5. Check the results.

   The key fingerprint (a colon-separated series of 2 digit hexadecimal values) is displayed. Check that the path to the key is correct. In the example, the path is /home/johndoe/.ssh/id_rsa.pub. At this point, you have created a public/private key pair.

6. Copy the public key and append the key to the $HOME/.ssh/authorized_keys file in your home directory on the remote host.

This article explains public key authentication in general. Ms office 2007 key generator free download. You may want to see guide to setting up public key authentication instead.

Do not confuse your user key pair used for authentication with host public key verification. Learn about all SSH key types.

Rsa

Public key authentication is an alternative means of identifying yourself to a login server, instead of typing a password. It is more secure and more flexible, but more difficult to set up.

In conventional password authentication, you prove you are who you claim to be by proving that you know the correct password. The only way to prove you know the password is to tell the server what you think the password is. This means that if the server has been hacked, or spoofed, an attacker can learn your password.

Public key authentication solves this problem. You generate a key pair, consisting of a public key (which everybody is allowed to know) and a private key (which you keep secret and do not give to anybody). The private key is able to generate signatures. A signature created using your private key cannot be forged by anybody who does not have that key; but anybody who has your public key can verify that a particular signature is genuine.

So you generate a key pair on your own computer, and you copy the public key to the server under a certain name. Then, when the server asks you to prove who you are, WinSCP can generate a signature using your private key. The server can verify that signature (since it has your public key) and allow you to log in. Now if the server is hacked or spoofed, the attacker does not gain your private key or password; they only gain one signature. And signatures cannot be re-used, so they have gained nothing.

There is a problem with this: if your private key is stored unprotected on your own computer, then anybody who gains access to that will be able to generate signatures as if they were you. So they will be able to log in to your server under your account. For this reason, your private key is usually encrypted when it is stored on your local machine, using a passphrase of your choice. In order to generate a signature, WinSCP must decrypt the key, so you have to type your passphrase.

This can make public-key authentication less convenient than password authentication: every time you log in to the server, instead of typing a short password, you have to type a longer passphrase. One solution to this is to use an authentication agent, a separate program which holds decrypted private keys and generates signatures on request. WinSCP can use PuTTY’s authentication agent, called Pageant. When you begin a Windows session, you start Pageant and load your private key into it (typing your passphrase once). For the rest of your session, you can start WinSCP any number of times and Pageant will automatically generate signatures without you having to do anything. When you close your Windows session, Pageant shuts down, without ever having stored your decrypted private key on disk. Many people feel this is a good compromise between security and convenience.

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Generating Public Private Rsa Key Pair Signature V1

There is more than one public-key algorithm available. The most common are RSA and ECDSA, but others exist, notably DSA (otherwise known as DSS), the USA’s federal Digital Signature Standard.1

To generate a key pair, use the PuTTYgen application.

You can start PuTTYgen directly from Authentication page of Advanced Site Settings dialog. If you start PuTTYgen this way, WinSCP will automatically pick up the generated key.

Different file formats are used to store SSH-2 private keys. WinSCP supports PuTTY format, as authors of PuTTY claim that it is the best one.

WinSCP also recognizes (but does not accept) the other two formats (OpenSSH and ssh.com), and it can convert the keys to PuTTY format for you. To convert the key file you can also use /keygen command-line switch or PuTTYgen application.

Generating Public/private Rsa Key Pair Ubuntu

1. The text is copy of PuTTY User Manual or was inspired by it.Back