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Ruby

Generate RSA SSH Key

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Generates an RSA SSH key and saves to various public and private key file formats (OpenSSH and PuTTY).

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Ruby
require 'chilkat'

success = false

key = Chilkat::CkSshKey.new()

# numBits may range from 384 to 4096.  Typical values are
# 1024 or 2048.  (must be a multiple of 64)
# A good choice for the exponent is 65537.  Chilkat recommends
# always using this value.
numBits = 2048
exponent = 65537
success = key.GenerateRsaKey(numBits,exponent)
if (success != true)
    print "Bad params passed to RSA key generation method." + "\n";
    exit
end

# Note: Generating a public/private key pair is CPU intensive
# and may take a short amount of time (more than few seconds,
# but less than a minute).

# Export the RSA private key to OpenSSH, PuTTY, and XML and save. 
exportEncrypted = false
exportedKey = key.toOpenSshPrivateKey(exportEncrypted)
# Chilkat provides a SaveText method for convenience...
success = key.SaveText(exportedKey,"privkey_openssh_unencrypted.pem")

# Export with encryption to OpenSSH private key format:
key.put_Password("secret")
exportEncrypted = true
exportedKey = key.toOpenSshPrivateKey(exportEncrypted)
success = key.SaveText(exportedKey,"privkey_openssh_encrypted.pem")

# Export the RSA private key to unencrypted PuTTY format:
exportEncrypted = false
exportedKey = key.toPuttyPrivateKey(exportEncrypted)
success = key.SaveText(exportedKey,"privkey_putty_unencrypted.ppk")

# Export the RSA private key to encrypted PuTTY format:
key.put_Password("secret")
exportEncrypted = true
exportedKey = key.toPuttyPrivateKey(exportEncrypted)
success = key.SaveText(exportedKey,"privkey_putty_encrypted.ppk")

# Export private key to XML:
exportedKey = key.toXml()
success = key.SaveText(exportedKey,"privkey.xml")

# ----------------------------------------------------
# Now for the public key....
# ----------------------------------------------------

# The Secure Shell (SSH) Public Key File Format
# is documented in RFC 4716.
exportedKey = key.toRfc4716PublicKey()
success = key.SaveText(exportedKey,"pubkey_rfc4716.pub")

# OpenSSH has a separate public-key file format, which 
# is also supported by Chilkat SshKey:
exportedKey = key.toOpenSshPublicKey()
success = key.SaveText(exportedKey,"pubkey_openSsh.pub")

print "Finished." + "\n";