RSA (Rivest–Shamir–Adleman) is one of the first public-key cryptosystems and is widely used for secure data transmission. In such a cryptosystem, the encryption key is public and distinct from the decryption key which is kept secret (private). 1 Generate a random 256-bit AES key. 2 Encrypt it with RSA2048 or 3072 or whatever size of RSA you have. 3 Encrypt your actual plaintext with AES256, using that random key. The two algorithms do different things; it's a little like asking why we need a hammer when we've got a power screwdriver. Now, RSA's strength depends on the size of its. Oct 01, 2019 # Generate Private Key and Certificate using RSA 256 encryption (4096-bit key) openssl req -x509 -newkey rsa:4096 -keyout privatekey.pem -out certificate.pem -days 365 # Alternatively, setting the '-newkey' parameter to 'rsa:2048' will generate a 2048-bit key.
That generates a 2048-bit RSA key pair, encrypts them with a password you provide and writes them to a file. You need to next extract the public key file. You will use this, for instance, on your web server to encrypt content so that it can only be read with the private key. Export the RSA Public Key to a File. This is a command that is. Nov 06, 2019 How to generate JWT RS256 key. GitHub Gist: instantly share code, notes, and snippets. 2048-bit RSA keys to 112-bit symmetric keys and 3072-bit RSA keys to 128-bit symmetric keys. RSA claims that. 2048-bit keys are sufficient until 2030. It's also possible to generate keys using openssl only. Generate 4098 Bit Key Generate 4096 Bit DSA Key. RSA is very old and popular asymmetric encryption algorithm. It is used most of the systems by default. There are some alternatives to RSA like DSA. We can not generate 4096 bit DSA keys because it algorithm do not supports. Generate 2048 Bit Key. The default key size for the ssh-keygen is 2048. Hyper Crypt is a free portable RSA key generator for Windows. It is basically a free software to encrypt files and folder with AES-256 encryption. You can also use it to encrypt a phrase with RSA, AES-256, or One Time Pad algorithm, to compute text, file, or folder hash values, and to securely shred files and folders. From its Tools section, you can find a Key Generator.
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.
Microsoft office professional 2007 keys. 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.
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.)
router (Config) # Line VTY 0 15
router (Config-line)# login local
router (Config-line)# Exit
router (Config)# username [loginid] password [cisco]
router (Config)# username loginid1 password cisco1
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.
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 |
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.
| 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. |
On September 19, in a conference room at the Pelican Hill Resort in Newport Beach, California, Crown Sterling CEO Robert Grant, COO Joseph Hopkins, and a pair of programmers staged a demonstration of Grant's claimed cryptography-cracking algorithm. Before an audience that a Crown Sterling spokesperson described as 'approximately 100 academics and business professionals,' Grant and Hopkins had their minions generate two pairs of 256-bit RSA encryption keys and then derive the prime numbers used to generate them from the public key in about 50 seconds.
In a phone interview with Ars Technica today, Grant said the video was filmed during a 'business session' at the event. The 'academic' presentation, which went into math behind his claims and a new paper yet to be published, was attended by 'mostly people from local colleges,' Hopkins said. Grant said that he didn't know who attended both sessions, and the CEO added that he didn't have access to the invitation list.
During the presentation, Grant called out to Chris Novak, the global director of Verizon Enterprise Solutions' Threat Research Advisory Center, naming him as a member of Crown Sterling's advisory board. The shout-out was during introductory remarks that Grant made about a survey of chief information security officers that the company had conducted. The survey found only 3% had an understanding of the fundamental math behind encryption.
The video of the demonstration is here. (The video was briefly marked as private, but is now back again.)
The demo was displayed from a MacBook Pro, but it appeared that it was being run in part via a secure shell session to a server. Grant claimed that the work could be used to 'decrypt' a 512-bit RSA key in 'as little as five hours' using what Grant described as 'standard computing.'
The demonstration only raises more skepticism about Grant's work and about Crown Sterling's main thrust—an encryption product called Time AI that Grant claims will use the time signature of AI-generated music to generate 'quantum-entangled' keys. Grant's efforts to show how weak long-cracked versions of RSA are was met with what can only be described as derision by a number of cryptography and security experts.
Mark Carney, a PhD candidate at the University of Leeds, used Msieve, a well-established factoring method, on his laptop. Carney cracked compound numbers larger than RSA keys into primes in about 20 seconds. 'These [were] not 256-bit keys, just larger-than 256-bit numbers,' he explained, but 'these are using standard quadratic sieve methods. So long as I haven't messed this preliminary test up too much, this is un-optimized Msieve out-performing Crown Sterling's algorithm by roughly 50 percent.'
Henryk Plötz, a computer scientist in Berlin, ran a test of his own, with similar results:
Well, this is Sagemath on my Ultrabook (X1 Carbon 2017).
I'm assuming the default implementation is single-threaded. So, '50 seconds' is exactly the expected performance on a 4-core laptop. pic.twitter.com/2WlvZaR0vk
— Henryk Plötz (@henrykploetz) September 20, 2019
So did security researcher Rob Graham of Errata Seccurity.
Magicians sawing women in half on stage are more convincing than a laptop a factoring 256-bit RSA keys in a hotel room.
— Rob Graham (@ErrataRob) September 20, 2019
Pressed on the issue of performance by Ars, Grant said that the presentation was only to demonstrate the vulnerability of the RSA algorithm. Grant insisted that weak RSA keys were still widely in use. 'Some banks still use DES encryption,' he said, referring to the Digital Encryption Standard—the 56 bit symmetric encryption technology developed by IBM in the 1970s that was still a federally approved standard for legacy systems until 2003. So, Grant insisted, the demonstration was still relevant.
Ars shared the video with Jake Williams, the founder of Rendition Infosec and a former member of the National Security Agency's Tailored Access Operations group. 'I'm dumber for having watched that,' Williams said. 'Bragging that you can factor a 256 bit RSA key in 2019 is like bragging about hacking an unpatched Windows 2000 box. Sure you did it, but nobody should care.' The 256-bit key, Williams said, was 'absurdly small.' (Digital certificates from recognized certificate authorities have used RSA 2048-bit keys for more than seven years.)
Williams had publicly challenged Crown Sterling last month to a third-party assessment of their crypto cracking capabilities:
The demonstration must be administered by a third party of my choosing, who will generate RSA keys at 2019's industry standard lengths for sensitive data protection (2048). Data will be encrypted and Crown Sterling will have the public key (as would be the norm in the wild). 2/
— Jake Williams (@MalwareJake) August 29, 20191
Nicholas Weaver, lecturer at the University of California Berkeley's Department of Electrical Engineering and Computer Sciences, reacted to Grant's latest demonstration with this statement to Ars:
It was previously an open question whether Mr Grant was a fraud or just delusional. His new press release now makes me certain he is a deliberate fraud.
He received a lot of feedback from cryptographers, both polite and rude, so showing this level of continued ignorance is willful at this point. His video starts with the ridiculously false notion that factoring is all there is for public key. He then insists that breaking a 256 bit RSA key or even a 512b key is somehow revolutionary. It's not. Professor [Nadia] Heninger at UCSD, as part of her work on the FREAK attack, showed that factoring a 512 bit key is easily accomplished with less than $100 of computing time in 2015.
His further suggesting that breaking 512-bit breaks RSA is also ridiculous on its face. Modern RSA is usually 2048 bits or higher, and there is a near-exponential increase in the difficulty of factoring with the number of bits.
At this point I have to conclude he is an outright fraud, and the most likely explanation is he's looking to raise investment from ignorant accredited investors. And now I wonder how many other companies he's started are effectively fraudulent.
In a blog post earlier this month, security expert and Harvard Kennedy School lecturer Bruce Schneier declared, 'Crown Sterling is complete and utter snake oil.' Grant laughed at the term, telling Ars he had ordered bottles of Pride of Strathspey Scotch Whisky with custom 'snake oil' labels.