Class | Net::SSH::Transport::CipherFactory |
In: |
lib/net/ssh/transport/cipher_factory.rb
lib/net/ssh/transport/cipher_factory.rb |
Parent: | Object |
Implements a factory of OpenSSL cipher algorithms.
SSH_TO_OSSL | = | { "3des-cbc" => "des-ede3-cbc", "blowfish-cbc" => "bf-cbc", "aes256-cbc" => "aes-256-cbc", "aes192-cbc" => "aes-192-cbc", "aes128-cbc" => "aes-128-cbc", "idea-cbc" => "idea-cbc", "cast128-cbc" => "cast-cbc", "rijndael-cbc@lysator.liu.se" => "aes-256-cbc", "none" => "none" | Maps the SSH name of a cipher to it‘s corresponding OpenSSL name | |
SSH_TO_OSSL | = | { "3des-cbc" => "des-ede3-cbc", "blowfish-cbc" => "bf-cbc", "aes256-cbc" => "aes-256-cbc", "aes192-cbc" => "aes-192-cbc", "aes128-cbc" => "aes-128-cbc", "idea-cbc" => "idea-cbc", "cast128-cbc" => "cast-cbc", "rijndael-cbc@lysator.liu.se" => "aes-256-cbc", "none" => "none" | Maps the SSH name of a cipher to it‘s corresponding OpenSSL name |
Retrieves a new instance of the named algorithm. The new instance will be initialized using an iv and key generated from the given iv, key, shared, hash and digester values. Additionally, the cipher will be put into encryption or decryption mode, based on the value of the encrypt parameter.
# File lib/net/ssh/transport/cipher_factory.rb, line 34 34: def self.get(name, options={}) 35: ossl_name = SSH_TO_OSSL[name] or raise NotImplementedError, "unimplemented cipher `#{name}'" 36: return IdentityCipher if ossl_name == "none" 37: 38: cipher = OpenSSL::Cipher::Cipher.new(ossl_name) 39: cipher.send(options[:encrypt] ? :encrypt : :decrypt) 40: 41: cipher.padding = 0 42: cipher.iv = make_key(cipher.iv_len, options[:iv], options) 43: cipher.key = make_key(cipher.key_len, options[:key], options) 44: 45: return cipher 46: end
Retrieves a new instance of the named algorithm. The new instance will be initialized using an iv and key generated from the given iv, key, shared, hash and digester values. Additionally, the cipher will be put into encryption or decryption mode, based on the value of the encrypt parameter.
# File lib/net/ssh/transport/cipher_factory.rb, line 34 34: def self.get(name, options={}) 35: ossl_name = SSH_TO_OSSL[name] or raise NotImplementedError, "unimplemented cipher `#{name}'" 36: return IdentityCipher if ossl_name == "none" 37: 38: cipher = OpenSSL::Cipher::Cipher.new(ossl_name) 39: cipher.send(options[:encrypt] ? :encrypt : :decrypt) 40: 41: cipher.padding = 0 42: cipher.iv = make_key(cipher.iv_len, options[:iv], options) 43: cipher.key = make_key(cipher.key_len, options[:key], options) 44: 45: return cipher 46: end
Returns a two-element array containing the [ key-length, block-size ] for the named cipher algorithm. If the cipher algorithm is unknown, or is "none", 0 is returned for both elements of the tuple.
# File lib/net/ssh/transport/cipher_factory.rb, line 52 52: def self.get_lengths(name) 53: ossl_name = SSH_TO_OSSL[name] 54: return [0, 0] if ossl_name.nil? || ossl_name == "none" 55: 56: cipher = OpenSSL::Cipher::Cipher.new(ossl_name) 57: return [cipher.key_len, cipher.block_size] 58: end
Returns a two-element array containing the [ key-length, block-size ] for the named cipher algorithm. If the cipher algorithm is unknown, or is "none", 0 is returned for both elements of the tuple.
# File lib/net/ssh/transport/cipher_factory.rb, line 52 52: def self.get_lengths(name) 53: ossl_name = SSH_TO_OSSL[name] 54: return [0, 0] if ossl_name.nil? || ossl_name == "none" 55: 56: cipher = OpenSSL::Cipher::Cipher.new(ossl_name) 57: return [cipher.key_len, cipher.block_size] 58: end
Returns true if the underlying OpenSSL library supports the given cipher, and false otherwise.
# File lib/net/ssh/transport/cipher_factory.rb, line 23 23: def self.supported?(name) 24: ossl_name = SSH_TO_OSSL[name] or raise NotImplementedError, "unimplemented cipher `#{name}'" 25: return true if ossl_name == "none" 26: return OpenSSL::Cipher.ciphers.include?(ossl_name) 27: end
Returns true if the underlying OpenSSL library supports the given cipher, and false otherwise.
# File lib/net/ssh/transport/cipher_factory.rb, line 23 23: def self.supported?(name) 24: ossl_name = SSH_TO_OSSL[name] or raise NotImplementedError, "unimplemented cipher `#{name}'" 25: return true if ossl_name == "none" 26: return OpenSSL::Cipher.ciphers.include?(ossl_name) 27: end