Class Net::SSH::Authentication::KeyManager
In: lib/net/ssh/authentication/key_manager.rb
lib/net/ssh/authentication/key_manager.rb
Parent: Object

This class encapsulates all operations done by clients on a user‘s private keys. In practice, the client should never need a reference to a private key; instead, they grab a list of "identities" (public keys) that are available from the KeyManager, and then use the KeyManager to do various private key operations using those identities.

The KeyManager also uses the Agent class to encapsulate the ssh-agent. Thus, from a client‘s perspective it is completely hidden whether an identity comes from the ssh-agent or from a file on disk.

Methods

add   add   agent   agent   clear!   clear!   each_identity   each_identity   finish   finish   new   new   sign   sign   use_agent=   use_agent=   use_agent?   use_agent?  

Included Modules

Loggable Loggable

Attributes

key_files  [R]  The list of user key files that will be examined
key_files  [R]  The list of user key files that will be examined
known_identities  [R]  The map of loaded identities
known_identities  [R]  The map of loaded identities
options  [R]  The map of options that were passed to the key-manager
options  [R]  The map of options that were passed to the key-manager

Public Class methods

Create a new KeyManager. By default, the manager will use the ssh-agent (if it is running).

[Source]

    # File lib/net/ssh/authentication/key_manager.rb, line 38
38:         def initialize(logger, options={})
39:           self.logger = logger
40:           @key_files = []
41:           @use_agent = true
42:           @known_identities = {}
43:           @agent = nil
44:           @options = options
45:         end

Create a new KeyManager. By default, the manager will use the ssh-agent (if it is running).

[Source]

    # File lib/net/ssh/authentication/key_manager.rb, line 38
38:         def initialize(logger, options={})
39:           self.logger = logger
40:           @key_files = []
41:           @use_agent = true
42:           @known_identities = {}
43:           @agent = nil
44:           @options = options
45:         end

Public Instance methods

Add the given key_file to the list of key files that will be used.

[Source]

    # File lib/net/ssh/authentication/key_manager.rb, line 58
58:         def add(key_file)
59:           key_files.push(File.expand_path(key_file)).uniq!
60:           self
61:         end

Add the given key_file to the list of key files that will be used.

[Source]

    # File lib/net/ssh/authentication/key_manager.rb, line 58
58:         def add(key_file)
59:           key_files.push(File.expand_path(key_file)).uniq!
60:           self
61:         end

Returns an Agent instance to use for communicating with an SSH agent process. Returns nil if use of an SSH agent has been disabled, or if the agent is otherwise not available.

[Source]

     # File lib/net/ssh/authentication/key_manager.rb, line 155
155:         def agent
156:           return unless use_agent?
157:           @agent ||= Agent.connect(logger)
158:         rescue AgentNotAvailable
159:           @use_agent = false
160:           nil
161:         end

Returns an Agent instance to use for communicating with an SSH agent process. Returns nil if use of an SSH agent has been disabled, or if the agent is otherwise not available.

[Source]

     # File lib/net/ssh/authentication/key_manager.rb, line 155
155:         def agent
156:           return unless use_agent?
157:           @agent ||= Agent.connect(logger)
158:         rescue AgentNotAvailable
159:           @use_agent = false
160:           nil
161:         end

Clear all knowledge of any loaded user keys. This also clears the list of default identity files that are to be loaded, thus making it appropriate to use if a client wishes to NOT use the default identity files.

[Source]

    # File lib/net/ssh/authentication/key_manager.rb, line 51
51:         def clear!
52:           key_files.clear
53:           known_identities.clear
54:           self
55:         end

Clear all knowledge of any loaded user keys. This also clears the list of default identity files that are to be loaded, thus making it appropriate to use if a client wishes to NOT use the default identity files.

[Source]

    # File lib/net/ssh/authentication/key_manager.rb, line 51
51:         def clear!
52:           key_files.clear
53:           known_identities.clear
54:           self
55:         end

Iterates over all available identities (public keys) known to this manager. As it finds one, it will then yield it to the caller. The origin of the identities may be from files on disk or from an ssh-agent. Note that identities from an ssh-agent are always listed first in the array, with other identities coming after.

[Source]

     # File lib/net/ssh/authentication/key_manager.rb, line 82
 82:         def each_identity
 83:           if agent
 84:             agent.identities.each do |key|
 85:               known_identities[key] = { :from => :agent }
 86:               yield key
 87:             end
 88:           end
 89:           
 90:           key_files.each do |file|
 91:             if File.readable?(file)
 92:               begin
 93:                 private_key = KeyFactory.load_private_key(file)
 94:                 key = private_key.send :public_key
 95:                 known_identities[key] = { :from => :file, :file => file }
 96:                 yield key
 97:               rescue Exception => e
 98:                 error { "could not load public key file `#{file}.pub': #{e.class} (#{e.message})" }
 99:               end
100:             end
101:           end
102: 
103:           self
104:         end

Iterates over all available identities (public keys) known to this manager. As it finds one, it will then yield it to the caller. The origin of the identities may be from files on disk or from an ssh-agent. Note that identities from an ssh-agent are always listed first in the array, with other identities coming after.

[Source]

     # File lib/net/ssh/authentication/key_manager.rb, line 82
 82:         def each_identity
 83:           if agent
 84:             agent.identities.each do |key|
 85:               known_identities[key] = { :from => :agent }
 86:               yield key
 87:             end
 88:           end
 89:           
 90:           key_files.each do |file|
 91:             if File.readable?(file)
 92:               begin
 93:                 private_key = KeyFactory.load_private_key(file)
 94:                 key = private_key.send :public_key
 95:                 known_identities[key] = { :from => :file, :file => file }
 96:                 yield key
 97:               rescue Exception => e
 98:                 error { "could not load public key file `#{file}.pub': #{e.class} (#{e.message})" }
 99:               end
100:             end
101:           end
102: 
103:           self
104:         end

This is used as a hint to the KeyManager indicating that the agent connection is no longer needed. Any other open resources may be closed at this time.

Calling this does NOT indicate that the KeyManager will no longer be used. Identities may still be requested and operations done on loaded identities, in which case, the agent will be automatically reconnected. This method simply allows the client connection to be closed when it will not be used in the immediate future.

[Source]

    # File lib/net/ssh/authentication/key_manager.rb, line 72
72:         def finish
73:           @agent.close if @agent
74:           @agent = nil
75:         end

This is used as a hint to the KeyManager indicating that the agent connection is no longer needed. Any other open resources may be closed at this time.

Calling this does NOT indicate that the KeyManager will no longer be used. Identities may still be requested and operations done on loaded identities, in which case, the agent will be automatically reconnected. This method simply allows the client connection to be closed when it will not be used in the immediate future.

[Source]

    # File lib/net/ssh/authentication/key_manager.rb, line 72
72:         def finish
73:           @agent.close if @agent
74:           @agent = nil
75:         end

Sign the given data, using the corresponding private key of the given identity. If the identity was originally obtained from an ssh-agent, then the ssh-agent will be used to sign the data, otherwise the private key for the identity will be loaded from disk (if it hasn‘t been loaded already) and will then be used to sign the data.

Regardless of the identity‘s origin or who does the signing, this will always return the signature in an SSH2-specified "signature blob" format.

[Source]

     # File lib/net/ssh/authentication/key_manager.rb, line 115
115:         def sign(identity, data)
116:           info = known_identities[identity] or raise KeyManagerError, "the given identity is unknown to the key manager"
117: 
118:           if info[:key].nil? && info[:from] == :file
119:             begin
120:               info[:key] = KeyFactory.load_private_key(info[:file], options[:passphrase])
121:             rescue Exception => e 
122:               raise KeyManagerError, "the given identity is known, but the private key could not be loaded: #{e.class} (#{e.message})"
123:             end
124:           end
125: 
126:           if info[:key]
127:             return Net::SSH::Buffer.from(:string, identity.ssh_type,
128:               :string, info[:key].ssh_do_sign(data.to_s)).to_s
129:           end
130: 
131:           if info[:from] == :agent
132:             raise KeyManagerError, "the agent is no longer available" unless agent
133:             return agent.sign(identity, data.to_s)
134:           end
135: 
136:           raise KeyManagerError, "[BUG] can't determine identity origin (#{info.inspect})"
137:         end

Sign the given data, using the corresponding private key of the given identity. If the identity was originally obtained from an ssh-agent, then the ssh-agent will be used to sign the data, otherwise the private key for the identity will be loaded from disk (if it hasn‘t been loaded already) and will then be used to sign the data.

Regardless of the identity‘s origin or who does the signing, this will always return the signature in an SSH2-specified "signature blob" format.

[Source]

     # File lib/net/ssh/authentication/key_manager.rb, line 115
115:         def sign(identity, data)
116:           info = known_identities[identity] or raise KeyManagerError, "the given identity is unknown to the key manager"
117: 
118:           if info[:key].nil? && info[:from] == :file
119:             begin
120:               info[:key] = KeyFactory.load_private_key(info[:file], options[:passphrase])
121:             rescue Exception => e 
122:               raise KeyManagerError, "the given identity is known, but the private key could not be loaded: #{e.class} (#{e.message})"
123:             end
124:           end
125: 
126:           if info[:key]
127:             return Net::SSH::Buffer.from(:string, identity.ssh_type,
128:               :string, info[:key].ssh_do_sign(data.to_s)).to_s
129:           end
130: 
131:           if info[:from] == :agent
132:             raise KeyManagerError, "the agent is no longer available" unless agent
133:             return agent.sign(identity, data.to_s)
134:           end
135: 
136:           raise KeyManagerError, "[BUG] can't determine identity origin (#{info.inspect})"
137:         end

Toggles whether the ssh-agent will be used or not. If true, an attempt will be made to use the ssh-agent. If false, any existing connection to an agent is closed and the agent will not be used.

[Source]

     # File lib/net/ssh/authentication/key_manager.rb, line 147
147:         def use_agent=(use_agent)
148:           finish if !use_agent
149:           @use_agent = use_agent
150:         end

Toggles whether the ssh-agent will be used or not. If true, an attempt will be made to use the ssh-agent. If false, any existing connection to an agent is closed and the agent will not be used.

[Source]

     # File lib/net/ssh/authentication/key_manager.rb, line 147
147:         def use_agent=(use_agent)
148:           finish if !use_agent
149:           @use_agent = use_agent
150:         end

Identifies whether the ssh-agent will be used or not.

[Source]

     # File lib/net/ssh/authentication/key_manager.rb, line 140
140:         def use_agent?
141:           @use_agent
142:         end

Identifies whether the ssh-agent will be used or not.

[Source]

     # File lib/net/ssh/authentication/key_manager.rb, line 140
140:         def use_agent?
141:           @use_agent
142:         end

[Validate]