Collaborate Disseminate
I recently generated a new SSH key in the ed25519 format.
The public key is only 69 bytes long while my old RSA key is 373 bytes.
From my perception ed25519 is the more recent and secure format.
So why isn’t longer better h… Continue reading Is it bad that my ed25519 key is so short compared to a RSA key?
Found a few issue threads, notably for Chrome (Chromium issue #478225), and the browser does appear to have dropped support for the secp521r1 curve (can test your browser using SSLLabs). There were other issue threads for other software pa… Continue reading Why is secp521r1 no longer supported in Chrome, others?
A lot of people recommend using Ed25519 instead of RSA keys for SSH.
The introduction page of Ed25519 (http://ed25519.cr.yp.to/) says:
[..] breaking it has similar difficulty to breaking [..] RSA with ~3000-bit keys [..]
So speaking only… Continue reading SSH Key: Ed25519 vs RSA
As far as I know, Curve25519 offers “only” a security level equal to an 128bit symmetric cipher.
I’d like to know if there are new (not NIST) curves, which provide a security-level comparable to a 256bit cipher AND already used by some app… Continue reading More secure curve than Curve25519
Is there any way to convert an ECC private key to RSA PKCS#1 format?
I have tried converting it to PKCS#8 first using OpenSSL:
openssl pkcs8 -topk8 -nocrypt -in EC_key.pem -out pkcs8_key.pem
This results in a pem file that is in (what … Continue reading Converting ECC Private key to PKCS#1 format
In elliptic curve cryptography what should be the length of session key? Is there a specific metric to choose one, or are they randomly generated?
I was studying one paper about defence against a Sybil attack. In the initial deployment sta… Continue reading length of a session key in EC?
I know how to do this with RSA keys (see this article: Determine if private key belongs to certificate?) however I do not know how to do this for ECDSA certificate / key pairs.
With RSA keys, the modulus can be used for this. However I’m … Continue reading How can you check if a private key and certificate match in OpenSSL with ECDSA?
Similar to how it can be easily done for RSA:
openssl req -x509 -nodes -newkey rsa:2048 -rand /dev/urandom -keyout example.key -out example.crt -days 365
I’d like to generate an ECDSA cert/key in one step. I’ve tried:
ope… Continue reading Generating ECDSA certificate and private key in one step
Among the Elliptic Curve Cryptography (ECC) algorithms available in OpenSSH (ECDH, ECDSA, Ed25519, Curve25519), which offers the best level of security, and (ideally) why?
Forgive me if this should be in the crypto sub, but sometimes the answers there are very mathematical and I would rather have an answer which is a bit lighter on the math.
I was watching the Cryptographer’s panel from RSA 2013 and at abou… Continue reading Why is ECC more vulnerable than RSA in a post-quantum world?