Module: Kitchen::Driver::Oci::Mixin::SshKeys::ED25519

Defined in:
lib/kitchen/driver/oci/mixin/ssh_keys.rb

Overview

Mixins required to generate a ED25519 key pair.

Author:

  • Justin Steele <justin.steele@oracle.com>

Instance Method Summary collapse

Instance Method Details

#encode_private_key(public_key, private_seed) ⇒ String

Encodes the private key.

Parameters:

  • public_key (String) —

    the byte representation of the Ed25519::VerifyKey.

  • private_seed (String) —

    the byte representation of the Ed25519::SigningKey.

Returns:

  • (String) 


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# File 'lib/kitchen/driver/oci/mixin/ssh_keys.rb', line 150

def encode_private_key(public_key, private_seed)
  buf  = header(public_key)
  priv = private_section(public_key, private_seed)
  padlen = (-priv.bytesize) & 7
  priv << (1..padlen).to_a.pack("C*")
  buf << pack_string(priv)
  b64 = Base64.strict_encode64(buf).scan(/.{1,70}/).join("\n")
  "-----BEGIN OPENSSH PRIVATE KEY-----\n#{b64}\n-----END OPENSSH PRIVATE KEY-----\n"
end

#encode_public_key(public_key) ⇒ String

Encodes the public key.

Parameters:

  • public_key (String) —

    the byte representation of the Ed25519::VerifyKey.

Returns:

  • (String) 


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# File 'lib/kitchen/driver/oci/mixin/ssh_keys.rb', line 195

def encode_public_key(public_key)
  blob = [algorithm.bytesize].pack("N") + algorithm + [public_key.bytesize].pack("N") + public_key
  [algorithm, Base64.strict_encode64(blob), config[:instance_name]].compact.join(" ")
end

#generate_key_pair ⇒ Object

Generates an ED25519 key pair to be used to SSH to the instance and updates the state with the full path to the private key.



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# File 'lib/kitchen/driver/oci/mixin/ssh_keys.rb', line 109

def generate_key_pair
  signing_key = Ed25519::SigningKey.generate
  private_seed = signing_key.to_bytes
  public_key = signing_key.verify_key.to_bytes
  write_private_key(public_key, private_seed)
  write_public_key(public_key)
  state.store(:ssh_key, private_key_file)
end

#header(public_key) ⇒ String

“openssh-key-v1” header: magic, cipher/kdf, nkeys, and the public key blob(s).

Parameters:

  • public_key (String) —

    the byte representation of the Ed25519::VerifyKey.

Returns:

  • (String) 


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# File 'lib/kitchen/driver/oci/mixin/ssh_keys.rb', line 164

def header(public_key)
  [
    "openssh-key-v1\0",
    pack_string("none"),  # ciphername
    pack_string("none"),  # kdfname
    pack_string(""),      # kdfoptions
    [1].pack("N"),        # nkeys
    pack_string(pub_blob(public_key)),
  ].join
end

#pack_string(str) ⇒ String

Packs a string as SSH “string” (4-byte len + bytes).

Parameters:

  • str (String) —

    the portion of the key being packed.

Returns:

  • (String) 


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# File 'lib/kitchen/driver/oci/mixin/ssh_keys.rb', line 122

def pack_string(str)
  [str.bytesize].pack("N") + str
end

#private_section(public_key, private_seed) ⇒ String

Correct private section: checkints, key fields, comment, padding

Parameters:

  • public_key (String) —

    the byte representation of the Ed25519::VerifyKey.

  • private_seed (String) —

    the byte representation of the Ed25519::SigningKey.

Returns:

  • (String) 


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# File 'lib/kitchen/driver/oci/mixin/ssh_keys.rb', line 180

def private_section(public_key, private_seed)
  checkint = SecureRandom.random_number(2**32)
  [
    [checkint, checkint].pack("N*"),
    pack_string(algorithm),
    pack_string(public_key),
    pack_string(private_seed + public_key),
    pack_string(config[:instance_name] || ""),
  ].join
end

#pub_blob(public_key) ⇒ String

SSH public key blob: string keytype + string key (32 bytes).

Parameters:

  • public_key (String) —

    the byte representation of the Ed25519::VerifyKey.

Returns:

  • (String) 


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# File 'lib/kitchen/driver/oci/mixin/ssh_keys.rb', line 204

def pub_blob(public_key)
  pack_string(algorithm) + pack_string(public_key)
end

#write_private_key(public_key, private_seed) ⇒ Object

Writes the encoded private key.

Parameters:

  • public_key (String) —

    the byte representation of the Ed25519::VerifyKey.

  • private_seed (String) —

    the byte representation of the Ed25519::SigningKey.



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# File 'lib/kitchen/driver/oci/mixin/ssh_keys.rb', line 130

def write_private_key(public_key, private_seed)
  private_key = encode_private_key(public_key, private_seed)
  File.open(private_key_file, "w") { |f| f.write(private_key) }
  File.chmod(0600, private_key_file)
end

#write_public_key(public_key) ⇒ Object

Writes the encoded public key.

Parameters:

  • public_key (String) —

    the byte representation of the Ed25519::VerifyKey.



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# File 'lib/kitchen/driver/oci/mixin/ssh_keys.rb', line 139

def write_public_key(public_key)
  pub_key = encode_public_key(public_key)
  File.open(public_key_file, "w") { |f| f.write(pub_key) }
  File.chmod(0600, public_key_file)
end