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Ruby

Convert PuTTY Private Key (ppk) to OpenSSH (pem)

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Convert a PuTTY format private key file (.ppk) to OpenSSH (.pem).

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Ruby
require 'chilkat'

success = false

key = Chilkat::CkSshKey.new()

# Load an unencrypted or encrypted PuTTY private key.

# If  your PuTTY private key is encrypted, set the Password
# property before calling FromPuttyPrivateKey.
# If your PuTTY private key is not encrypted, it makes no diffference
# if Password is set or not set.
key.put_Password("secret")

# First load the .ppk file into a string:

keyStr = key.loadText("putty_private_key.ppk")

# Import into the SSH key object:
success = key.FromPuttyPrivateKey(keyStr)
if (success != true)
    print key.lastErrorText() + "\n";
    exit
end

# Convert to an encrypted or unencrypted OpenSSH key.

# First demonstrate converting to an unencrypted OpenSSH key

bEncrypt = false
unencryptedKeyStr = key.toOpenSshPrivateKey(bEncrypt)
success = key.SaveText(unencryptedKeyStr,"unencrypted_openssh.pem")
if (success != true)
    print key.lastErrorText() + "\n";
    exit
end

# Save to an encrypted OpenSSH PEM file:

bEncrypt = true
key.put_Password("myPassword")
encryptedKeyStr = key.toOpenSshPrivateKey(bEncrypt)
success = key.SaveText(encryptedKeyStr,"encrypted_openssh.pem")
if (success != true)
    print key.lastErrorText() + "\n";
    exit
end

print "Done!" + "\n";