OpenSSH Public Key Parser for Python

This library validates OpenSSH public keys.

Currently ssh-rsa, ssh-dss (DSA), ssh-ed25519 and ecdsa keys with NIST curves are supported.

Installation:

pip install sshpubkeys

or clone the repository and use

python setup.py install

Usage:

from sshpubkeys import SSHKey
ssh = SSHKey("ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAAAYQCxO38tKAJXIs9ivPxt7AY"
      "dfybgtAR1ow3Qkb9GPQ6wkFHQqcFDe6faKCxH6iDRteo4D8L8B"
      "xwzN42uZSB0nfmjkIxFTcEU3mFSXEbWByg78aoddMrAAjatyrh"
      "H1pON6P0= ojarva@ojar-laptop")
print(ssh.bits) # 768
print(ssh.hash()) # 56:84:1e:90:08:3b:60:c7:29:70:5f:5e:25:a6:3b:86

Exceptions

• NotImplementedError if invalid ecdsa curve or unknown key type is encountered.

• InvalidKeyException if any other error is encountered:

  • TooShortKeyException if key is too short (<768 bits for RSA, <1024 for DSA, <256 for ED25519)
  • TooLongKeyException if key is too long (>16384 for RSA, >1024 for DSA, >256 for ED25519)
  • InvalidTypeException if key type (“ssh-rsa” in above example) does not match to what is included in base64 encoded data.
  • MalformedDataException if decoding and extracting the data fails.

Tests

See “tests/” folder for unit tests. Use

python setup.py test

or

python3 setup.py test

to run test suite. If you have keys that are not parsed properly, or malformed keys that raise incorrect exception, please send your public key to olli@jarva.fi, and I’ll include it. Alternatively, create a new issue or make a pull request in github.