ecc)

Asked Jan 16 '23 at 04:41

Active Jan 16 '23 at 04:50

Viewed 161 times

I have many private keys in a format looking like this:

-----BEGIN ENCRYPTED PRIVATE KEY-----
...
-----END ENCRYPTED PRIVATE KEY-----

I would like to remove the passphrase from these keys using the python PyCryptodome lib. I do know the passphrase.
However, I do not know the key type of each key (They are a mix of RSA/DSA/ECC keys).

Is there any way to detect the key type, so that I can use the correct procedure to import/export the key?
(e.g. Crypto.PublicKey.RSA.import_key , Crypto.PublicKey.ECC.import_key)

Currently, I'm doing this, which is rather ugly:

try:
    rsa_key_decrypted = RSA.import_key(key, key_passphrase)
    decrypted_key = rsa_key_decrypted.export_key(pkcs=8).decode('ascii')
except:
    try:
        dsa_key_decrypted = DSA.import_key(key, key_passphrase)
        decrypted_key = dsa_key_decrypted.export_key().decode('ascii')
    except:
        ecc_key_decrypted = ECC.import_key(key, key_passphrase)
        decrypted_key = ecc_key_decrypted.export_key(format='PEM')

edited Jan 16 '23 at 04:50

asked Jan 16 '23 at 04:41

Zulakis

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Decode them using the first algorithm, then try the next one if that fails. Repeat until you find the correct one. – Selcuk Jan 16 '23 at 04:44
@Selcuk That's what I'm currently doing (see edit). However, that is rather ugly and I'd love a more straight-forward solution. – Zulakis Jan 16 '23 at 04:50
Nope, that's the way. – Tim Roberts Jan 16 '23 at 05:00

Python - Detect type of private key (rsa/dsa/ecc)

0 Answers0