Public Private Key Generator C Rating: 7,7/10 2897 votes
  • Nov 06, 2019  sh-4.4$ ssh-keygen -t rsa -b 4096 -f jwtRS256.key Generating public/private rsa key pair. Enter passphrase (empty for no passphrase): Enter same passphrase again: Your identification has been saved in jwtRS256.key. Your public key has been saved in jwtRS256.key.pub.
  • May 06, 2014  Private Key: A private key is a tiny bit of code that is paired with a public key to set off algorithms for text encryption and decryption. It is created as part of public key cryptography during asymmetric-key encryption and used to decrypt and transform a message to a readable format. Public and private keys are paired for secure.
  • MyLocalHost% ssh-keygen Generating public/private rsa key pair. Enter file in which to save the key(/home/johndoe/.ssh/idrsa): Enter the path to the file that will hold the key. By default, the file name idrsa, which represents an RSA v2 key, appears in parentheses.
Documentation » Getting Started » Protocols » SSH » Using Public Keys for Authentication »

Jul 30, 2018  Private Key: A private key is a sophisticated form of cryptography that allows a user to access his or her cryptocurrency. A private key is an integral aspect of bitcoin and altcoins, and its. The private key is created from a secure random number generator, or derived from a seed value (that is created by a secure random number generator). The public key is created from the private key (in Elliptic Curve Cryptography), and the address is the cryptographic hash of that public key (with potentially some other data, like network ID and checksum, to prevent mistyping). An Online RSA Public and Private Key Generator. Sep 6 th, 2013. I was recently in a meeting where a person needed to generate a private and public key for RSA encryption, but they were using a PC (Windows). This is something that is easily done via a terminal using ssh-keygen on Mac and Linux.

PuTTYgen is a key generator. It generates pairs of public and private keys to be used with WinSCP. PuTTYgen generates RSA, DSA, ECDSA, and Ed25519 keys.

PuTTYgen is included in the WinSCP installation package. You can also download it separately from the WinSCP download page.

PuTTYgen originates from PuTTY and is also part of the PuTTY installation package. It does not matter if you use PuTTYgen from WinSCP or the PuTTY installation package, they are identical.

To start PuTTYgen, go to Tools > PuTTYgen on Login dialog.

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When you run PuTTYgen you will see a window where you have two main choices: Generate, to generate a new public/private key pair, or Load to load in an existing private key.

This is a general outline of the procedure for generating a new key pair. The following sections describe the process in more detail.

  • First, you need to select which type of key you want to generate, and also select the strength of the key.
  • Then press the Generate button, to actually generate the key.
  • Once you have generated the key, select a comment field and a passphrase.
  • Now you’re ready to save the private key to disk; press the Save private key button.

Your key pair is now ready for use. You may also want to copy the public key to your server, either by copying it out of the Public key for pasting into OpenSSH authorized_keys file box, or by using the Save public key button. However, you don’t need to do this immediately; if you want, you can load the private key back into PuTTYgen later and the public key will be available for copying and pasting again.

For more details refer to guide to setting up public key authentication.

Before generating a key pair using PuTTYgen, you need to select which type of key you need.

The current version of the SSH protocol, SSH-2, supports several different key types. PuTTYgen can generate:

  • An RSA key for use with the SSH-2 protocol.
  • A DSA key for use with the SSH-2 protocol.
  • An ECDSA (elliptic curve DSA) key for use with the SSH-2 protocol.
  • An Ed25519 key (another elliptic curve algorithm) for use with the SSH-2 protocol.

PuTTYgen can also generate an RSA key suitable for use with the old SSH-1 protocol (which only supports RSA); for this, you need to select the SSH-1 (RSA) option. Since the SSH-1 protocol is no longer considered secure, it’s rare to need this option.

The Number of bits input box allows you to choose the strength of the key PuTTYgen will generate.

For RSA, 2048 bits should currently be sufficient for most purposes.

For ECDSA, only 256, 384, and 521 bits are supported. (ECDSA offers equivalent security to RSA with smaller key sizes.)

For Ed25519, the only valid size is 256 bits.

Once you have chosen the type of key you want, and the strength of the key, press the Generate button and PuTTYgen will begin the process of actually generating the key.

First, a progress bar will appear and PuTTYgen will ask you to move the mouse around to generate randomness. Wave the mouse in circles over the blank area in the PuTTYgen window, and the progress bar will gradually fill up as PuTTYgen collects enough randomness. You don’t need to wave the mouse in particularly imaginative patterns (although it can’t hurt); PuTTYgen will collect enough randomness just from the fine detail of exactly how far the mouse has moved each time Windows samples its position.

When the progress bar reaches the end, PuTTYgen will begin creating the key. The progress bar will reset to the start, and gradually move up again to track the progress of the key generation. It will not move evenly, and may occasionally slow down to a stop; this is unfortunately unavoidable, because key generation is a random process and it is impossible to reliably predict how long it will take.

When the key generation is complete, a new set of controls will appear in the window to indicate this.

The Key fingerprint box shows you a fingerprint value for the generated key. This is derived cryptographically from the public key value, so it doesn’t need to be kept secret; it is supposed to be more manageable for human beings than the public key itself.

The fingerprint value is intended to be cryptographically secure, in the sense that it is computationally infeasible for someone to invent a second key with the same fingerprint, or to find a key with a particular fingerprint.

If you have more than one key and use them for different purposes, you don’t need to memorize the key fingerprints in order to tell them apart. PuTTYgen allows you to enter a comment for your key, which will be displayed whenever WinSCP or Pageant asks you for the passphrase.

The default comment format, if you don’t specify one, contains the key type and the date of generation, such as rsa-key-20011212. Another commonly used approach is to use your name and the name of the computer the key will be used on, such as simon@simons-pc.

To alter the key comment, just type your comment text into the Key comment box before saving the private key. If you want to change the comment later, you can load the private key back into PuTTYgen, change the comment, and save it again.

The Key passphrase and Confirm passphrase boxes allow you to choose a passphrase for your key. The passphrase will be used to encrypt the key on disk, so you will not be able to use the key without first entering the passphrase.

When you save the key, PuTTYgen will check that the Key passphrase and Confirm passphrase boxes both contain exactly the same passphrase, and will refuse to save the key otherwise.

If you leave the passphrase fields blank, the key will be saved unencrypted. /world-of-warships-key-generator.html. You should not do this without good reason; if you do, your private key file on disk will be all an attacker needs to gain access to any machine configured to accept that key. If you want to be able to passwordless log in without having to type a passphrase every time, you should consider using Pageant so that your decrypted key is only held in memory rather than on disk.

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Under special circumstances you may genuinely need to use a key with no passphrase; for example, if you need to run an automated batch script that needs to make an SSH connection, you can’t be there to type the passphrase. In this case we recommend you generate a special key for each specific batch script (or whatever) that needs one, and on the server side you should arrange that each key is restricted so that it can only be used for that specific purpose. The documentation for your SSH server should explain how to do this (it will probably vary between servers).

Choosing a good passphrase is difficult. Just as you shouldn’t use a dictionary word as a password because it’s easy for an attacker to run through a whole dictionary, you should not use a song lyric, quotation or other well-known sentence as a passphrase. If you want your passphrase to make grammatical sense, this cuts down the possibilities a lot and you should use a longer one as a result.

Do not forget your passphrase. There is no way to recover it.

Once you have generated a key, set a comment field and set a passphrase, you are ready to save your private key to disk.

Press the Save private key button. PuTTYgen will put up a dialog box asking you where to save the file. Select a directory, type in a file name, and press Save.

This file is in PuTTY’s native format (*.PPK); it is the one you will need to tell WinSCP to use for authentication.

If you have started PuTTYgen from SSH > Authentication page of Advanced Site Settings dialog, WinSCP automatically detects the saved key and will insert its path it into Private key file box.

RFC 4716 specifies a standard format for storing SSH-2 public keys on disk. Some SSH servers (such as ssh.com’s) require a public key in this format in order to accept authentication with the corresponding private key. (Others, such as OpenSSH, use a different format)

To save your public key in the SSH-2 standard format, press the Save public key button in PuTTYgen. PuTTYgen will put up a dialog box asking you where to save the file. Select a directory, type in a file name, and press Save.

You will then probably want to copy the public key file to your SSH server machine.

If you use this option with an SSH-1 key, the file PuTTYgen saves will contain exactly the same text that appears in the Public key for pasting box. This is the only existing standard for SSH-1 public keys.

The OpenSSH server, among others, requires your public key to be given to it in a one-line format before it will accept authentication with your private key. (SSH-1 servers also used this method.)

The Public key for pasting into OpenSSH authorized_keys file gives the public-key data in the correct one-line format.

For more details refer to guide to setting up public key authentication.

WinSCP can show you the public key too.

PuTTYgen allows you to load an existing private key file into memory. If you do this, you can then change the passphrase and comment before saving it again; you can also make extra copies of the public key.

To load an existing key, press the Load button. PuTTYgen will display a dialog box where you can browse around the file system and find your key file. Once you select the file, PuTTYgen will ask you for a passphrase (if necessary) and will then display the key details in the same way as if it had just generated the key.

If you use the Load command to load a foreign key format, it will work, but you will see a message box warning you that the key you have loaded is not a PuTTY native key. See below for information about importing foreign key formats.

SSH-2 private keys have no standard format. OpenSSH and ssh.com have different formats, and WinSCP’s is different again. So a key generated with one client cannot immediately be used with another.

Using the Import command from the Conversions menu, PuTTYgen can load SSH-2 private keys in OpenSSH’s format and ssh.com’s format. Once you have loaded one of these key types, you can then save it back out as a PuTTY-format key (*.PPK) so that you can use it with the WinSCP. The passphrase will be unchanged by this process (unless you deliberately change it). You may want to change the key comment before you save the key, since some OpenSSH key formats contained no space for a comment, and ssh.com’s default comment format is long and verbose.

PuTTYgen can also export private keys in OpenSSH format and in ssh.com format. To do so, select one of the Export options from the Conversions menu. Exporting a key works exactly like saving it – you need to have typed your passphrase in beforehand, and you will be warned if you are about to save a key without a passphrase.

For OpenSSH there are two options. Modern OpenSSH actually has two formats it uses for storing private keys. Export OpenSSH key will automatically choose the oldest format supported for the key type, for maximum backward compatibility with older versions of OpenSSH; for newer key types like Ed25519, it will use the newer format as that is the only legal option. If you have some specific reason for wanting to use OpenSSH’s newer format even for RSA, DSA, or ECDSA keys, you can choose Export OpenSSH key (force new file format).

Most clients for the older SSH-1 protocol use a standard format for storing private keys on disk. PuTTY uses this format as well; so if you have generated an SSH-1 private key using OpenSSH or ssh.com’s client, you can use it with WinSCP, and vice versa. Hence, the export options are not available if you have generated an SSH-1 key.1

You can also use WinSCP /keygen command-line switch to convert the private key from other formats.

  1. The text is copy of PuTTY User Manual or was inspired by it.Back
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Creating and managing keys is an important part of the cryptographic process. Symmetric algorithms require the creation of a key and an initialization vector (IV). The key must be kept secret from anyone who should not decrypt your data. The IV does not have to be secret, but should be changed for each session. Asymmetric algorithms require the creation of a public key and a private key. The public key can be made public to anyone, while the private key must known only by the party who will decrypt the data encrypted with the public key. This section describes how to generate and manage keys for both symmetric and asymmetric algorithms.

Symmetric Keys

The symmetric encryption classes supplied by the .NET Framework require a key and a new initialization vector (IV) to encrypt and decrypt data. Whenever you create a new instance of one of the managed symmetric cryptographic classes using the parameterless constructor, a new key and IV are automatically created. Anyone that you allow to decrypt your data must possess the same key and IV and use the same algorithm. Generally, a new key and IV should be created for every session, and neither the key nor IV should be stored for use in a later session.

To communicate a symmetric key and IV to a remote party, you would usually encrypt the symmetric key by using asymmetric encryption. Sending the key across an insecure network without encrypting it is unsafe, because anyone who intercepts the key and IV can then decrypt your data. For more information about exchanging data by using encryption, see Creating a Cryptographic Scheme.

The following example shows the creation of a new instance of the TripleDESCryptoServiceProvider class that implements the TripleDES algorithm.

When the previous code is executed, a new key and IV are generated and placed in the Key and IV properties, respectively.

Key

Sometimes you might need to generate multiple keys. In this situation, you can create a new instance of a class that implements a symmetric algorithm and then create a new key and IV by calling the GenerateKey and GenerateIV methods. The following code example illustrates how to create new keys and IVs after a new instance of the symmetric cryptographic class has been made.

Private Key Generator 3.0

When the previous code is executed, a key and IV are generated when the new instance of TripleDESCryptoServiceProvider is made. Another key and IV are created when the GenerateKey and GenerateIV methods are called.

Asymmetric Keys

The .NET Framework provides the RSACryptoServiceProvider and DSACryptoServiceProvider classes for asymmetric encryption. These classes create a public/private key pair when you use the parameterless constructor to create a new instance. Asymmetric keys can be either stored for use in multiple sessions or generated for one session only. While the public key can be made generally available, the private key should be closely guarded.

A public/private key pair is generated whenever a new instance of an asymmetric algorithm class is created. After a new instance of the class is created, the key information can be extracted using one of two methods:

  • The ToXmlString method, which returns an XML representation of the key information.

  • The ExportParameters method, which returns an RSAParameters structure that holds the key information.

Both methods accept a Boolean value that indicates whether to return only the public key information or to return both the public-key and the private-key information. An RSACryptoServiceProvider class can be initialized to the value of an RSAParameters structure by using the ImportParameters method.

Public Private Key Generator

Asymmetric private keys should never be stored verbatim or in plain text on the local computer. If you need to store a private key, you should use a key container. For more on how to store a private key in a key container, see How to: Store Asymmetric Keys in a Key Container.

The following code example creates a new instance of the RSACryptoServiceProvider class, creating a public/private key pair, and saves the public key information to an RSAParameters structure.

Public Private Key Generator Cost

See also