Generate 1024-bit Rsa Keys Command
/ Using Encrypted Connections / Creating SSL and RSA Certificates and Keys / Creating SSL Certificates and Keys Using openssl 5.3.2 Creating SSL Certificates and Keys Using openssl This section describes how to use the openssl command to set up SSL certificate and key files for use by MySQL servers and clients.
Download and install the OpenSSL runtimes. If you are running Windows, grab the Cygwin package.
- Use this command to generate RSA key pairs for your Cisco device (such as a router). RSA keys are generated in pairs-one public RSA key and one private RSA key. If your router already has RSA keys when you issue this command, you will be warned and prompted to replace the existing keys with new keys.
- While Encrypting a File with a Password from the Command Line using OpenSSL is very useful in its own right, the real power of the OpenSSL library is its ability to support the use of public key cryptograph for encrypting or validating data in an unattended manner (where the password is not required to encrypt) is done with public keys.
- How I create RSA key and enable SSH access in Cisco VG202, in a Cisco router I use the next commands(but in a VG not exists): conf t crypto key generate rsa modulus 1024 ip domain-name domain-name ip ssh version 2 ip ssh time-out 120 ip ssh authentication-retries 3 line vty 0 4 transport input telne.
OpenSSL can generate several kinds of public/private keypairs.RSA is the most common kind of keypair generation.[1]
Other popular ways of generating RSA public key / private key pairs include PuTTYgen and ssh-keygen.[2][3]
Generate an RSA keypair with a 2048 bit private key[edit]
Execute command: 'openssl genpkey -algorithm RSA -out private_key.pem -pkeyopt rsa_keygen_bits:2048'[4] (previously “openssl genrsa -out private_key.pem 2048”)
e.g.
Make sure to prevent other users from reading your key by executing chmod go-r private_key.pem afterward.
Extracting the public key from an RSA keypair[edit]
Execute command: 'openssl rsa -pubout -in private_key.pem -out public_key.pem'
e.g.
A new file is created, public_key.pem, with the public key.
It is relatively easy to do some cryptographic calculations to calculate the public key from the prime1 and prime2 values in the public key file.However, OpenSSL has already pre-calculated the public key and stored it in the private key file.So this command doesn't actually do any cryptographic calculation -- it merely copies the public key bytes out of the file and writes the Base64 PEM encoded version of those bytes into the output public key file.[5]
Viewing the key elements[edit]
Execute command: 'openssl rsa -text -in private_key.pem'
All parts of private_key.pem are printed to the screen. This includes the modulus (also referred to as public key and n), public exponent (also referred to as e and exponent; default value is 0x010001), private exponent, and primes used to create keys (prime1, also called p, and prime2, also called q), a few other variables used to perform RSA operations faster, and the Base64 PEM encoded version of all that data.[6](The Base64 PEM encoded version of all that data is identical to the private_key.pem file).
Password-less login[edit]
Often a person will set up an automated backup process that periodically backs up all the content on one 'working' computer onto some other 'backup' computer.
Because that person wants this process to run every night, even if no human is anywhere near either one of these computers, using a 'password-protected' private key won't work -- that person wants the backup to proceed right away, not wait until some human walks by and types in the password to unlock the private key.Many of these people generate 'a private key with no password'.[7]Some of these people, instead, generate a private key with a password,and then somehow type in that password to 'unlock' the private key every time the server reboots so that automated toolscan make use of the password-protected keys.[8][3]
Patch Rsa 1024 Public Key
Further reading[edit]
- ↑Key Generation
- ↑Michael Stahnke.'Pro OpenSSH'.p. 247.
- ↑ ab'SourceForge.net Documentation: SSH Key Overview'
- ↑'genpkey(1) - Linux man page'
- ↑'Public – Private key encryption using OpenSSL'
- ↑'OpenSSL 1024 bit RSA Private Key Breakdown'
- ↑'DreamHost: Personal Backup'.
- ↑Troy Johnson.'Using Rsync and SSH: Keys, Validating, and Automation'.
- Internet_Technologies/SSH describes how to use 'ssh-keygen' and 'ssh-copy-id' on your local machine so you can quickly and securely ssh from your local machine to a remote host.
- October 2, 2015
- Posted by: Syed Shujaat
- Category: Cisco, Networking Solutions
Use this command to generate RSA key pairs for your Cisco device (such as a router). keys are generated in pairs–one public RSA key and one private RSA key.
If your router already has RSA keys when you issue this command, you will be warned and prompted to replace the existing keys with new keys. /putty-generate-rsa-public-key.html.
NOTE: Before issuing this command, ensure that your router has a hostname and IP domain name configured (with the hostname and ipdomain-name commands).
You will be unable to complete the cryptokeygeneratersacommand without a hostname and IP domain name. (This situation is not true when you generate only a named key pair.)
Here are the steps to Enable SSH and Crypto Key setup : 2 config must requried for SSH
1 Setup Local VTY line User ID and password
router (Config) # Line VTY 0 15
router (Config-line)# login local
router (Config-line)# Exit
!!! create local login ID/Pass
router (Config)# username [loginid] password [cisco]
router (Config)# username loginid1 password cisco1
2. router (Config)# ip domain-name example.com
router (Config)# crypto key generate rsa
how many bits in the modulus [512] :1024
router (Config)# ip ssh version2
router (Config)# CTRL Z
Note | Secure Shell (SSH) may generate an additional RSA key pair if you generate a key pair on a router having no RSA keys. The additional key pair is used only by SSH and will have a name such as {router_FQDN }.server. For example, if a router name is “router1.cisco.com,” the key name is “router1.cisco.com.server.” |
This command is not saved in the router configuration; however, the RSA keys generated by this command are saved in the private configuration in NVRAM (which is never displayed to the user or backed up to another device) the next time the configuration is written to NVRAM.
Modulus Length
When you generate RSA keys, you will be prompted to enter a modulus length. The longer the modulus, the stronger the security. However, a longer modules take longer to generate (see the table below for sample times) and takes longer to use.
The size of Key Modulus range from 360 to 2048. Choosing modulus greater than 512 will take longer time.
Router | 360 bits | 512 bits | 1024 bits | 2048 bits (maximum) |
---|---|---|---|---|
Cisco 2500 | 11 seconds | 20 seconds | 4 minutes, 38 seconds | More than 1 hour |
Cisco 4700 | Less than 1 second | 1 second | 4 seconds | 50 seconds |
Generate 1024-bit Rsa Keys
Cisco IOS software does not support a modulus greater than 4096 bits. A length of less than 512 bits is normally not recommended. In certain situations, the shorter modulus may not function properly with IKE, so we recommend using a minimum modulus of 2048 bits.
Syntax Description : Optional Strings to embed with SSH Crypto key
general-keys | (Optional) Specifies that a general-purpose key pair will be generated, which is the default. | ||
usage-keys | (Optional) Specifies that two RSA special-usage key pairs, one encryption pair and one signature pair, will be generated. | ||
signature | (Optional) Specifies that the RSA public key generated will be a signature special usage key. | ||
encryption | (Optional) Specifies that the RSA public key generated will be an encryption special usage key. | ||
labelkey-label | (Optional) Specifies the name that is used for an RSA key pair when they are being exported.If a key label is not specified, the fully qualified domain name (FQDN) of the router is used. | ||
exportable | (Optional) Specifies that the RSA key pair can be exported to another Cisco device, such as a router. | ||
modulusmodulus-size | (Optional) Specifies the IP size of the key modulus.By default, the modulus of a certification authority (CA) key is 1024 bits. The recommended modulus for a CA key is 2048 bits. The range of a CA key modulus is from 350 to 4096 bits.
| ||
storagedevicename: | (Optional) Specifies the key storage location. The name of the storage device is followed by a colon (:). | ||
redundancy | (Optional) Specifies that the key should be synchronized to the standby CA. | ||
ondevicename: | (Optional) Specifies that the RSA key pair will be created on the specified device, including a Universal Serial Bus (USB) token, local disk, or NVRAM. The name of the device is followed by a colon (:).Keys created on a USB token must be 2048 bits or less. |
Command | Description |
---|---|
copy | Copies any file from a source to a destination, use the copy command in privileged EXEC mode. |
cryptokeystorage | Sets the default storage location for RSA key pairs. |
debugcryptoengine | Displays debug messages about crypto engines. |
hostname | Specifies or modifies the hostname for the network server. |
ipdomain-name | Defines a default domain name to complete unqualified hostnames (names without a dotted-decimal domain name). |
showcryptokeymypubkeyrsa | Displays the RSA public keys of your router. |
show crypto pki certificates | Displays information about your PKI certificate, certification authority, and any registration authority certificates. |