--- /dev/null
+require 'base64'
+require 'openssl'
+
+module MCollective
+ module Security
+ # Impliments a public/private key based message validation system using SSL
+ # public and private keys.
+ #
+ # The design goal of the plugin is two fold:
+ #
+ # - give different security credentials to clients and servers to avoid
+ # a compromised server from sending new client requests.
+ # - create a token that uniquely identify the client - based on the filename
+ # of the public key
+ #
+ # To setup you need to create a SSL key pair that is shared by all nodes.
+ #
+ # openssl genrsa -out mcserver-private.pem 1024
+ # openssl rsa -in mcserver-private.pem -out mcserver-public.pem -outform PEM -pubout
+ #
+ # Distribute the private and public file to /etc/mcollective/ssl on all the nodes.
+ # Distribute the public file to /etc/mcollective/ssl everywhere the client code runs.
+ #
+ # Now you should create a key pair for every one of your clients, here we create one
+ # for user john - you could also if you are less concerned with client id create one
+ # pair and share it with all clients:
+ #
+ # openssl genrsa -out john-private.pem 1024
+ # openssl rsa -in john-private.pem -out john-public.pem -outform PEM -pubout
+ #
+ # Each user has a unique userid, this is based on the name of the public key.
+ # In this example case the userid would be 'john-public'.
+ #
+ # Store these somewhere like:
+ #
+ # /home/john/.mc/john-private.pem
+ # /home/john/.mc/john-public.pem
+ #
+ # Every users public key needs to be distributed to all the nodes, save the john one
+ # in a file called:
+ #
+ # /etc/mcollective/ssl/clients/john-public.pem
+ #
+ # If you wish to use registration or auditing that sends connections over MC to a
+ # central host you will need also put the server-public.pem in the clients directory.
+ #
+ # You should be aware if you do add the node public key to the clients dir you will in
+ # effect be weakening your overall security. You should consider doing this only if
+ # you also set up an Authorization method that limits the requests the nodes can make.
+ #
+ # client.cfg:
+ #
+ # securityprovider = ssl
+ # plugin.ssl_server_public = /etc/mcollective/ssl/server-public.pem
+ # plugin.ssl_client_private = /home/john/.mc/john-private.pem
+ # plugin.ssl_client_public = /home/john/.mc/john-public.pem
+ #
+ # If you have many clients per machine and dont want to configure the main config file
+ # with the public/private keys you can set the following environment variables:
+ #
+ # export MCOLLECTIVE_SSL_PRIVATE=/home/john/.mc/john-private.pem
+ # export MCOLLECTIVE_SSL_PUBLIC=/home/john/.mc/john-public.pem
+ #
+ # server.cfg:
+ #
+ # securityprovider = ssl
+ # plugin.ssl_server_private = /etc/mcollective/ssl/server-private.pem
+ # plugin.ssl_server_public = /etc/mcollective/ssl/server-public.pem
+ # plugin.ssl_client_cert_dir = /etc/mcollective/etc/ssl/clients/
+ #
+ # # Log but accept messages that may have been tampered with
+ # plugin.ssl.enforce_ttl = 0
+ #
+ # Serialization can be configured to use either Marshal or YAML, data types
+ # in and out of mcollective will be preserved from client to server and reverse
+ #
+ # You can configure YAML serialization:
+ #
+ # plugins.ssl_serializer = yaml
+ #
+ # else the default is Marshal. Use YAML if you wish to write a client using
+ # a language other than Ruby that doesn't support Marshal.
+ #
+ # Validation is as default and is provided by MCollective::Security::Base
+ #
+ # Initial code was contributed by Vladimir Vuksan and modified by R.I.Pienaar
+ class Ssl < Base
+ # Decodes a message by unserializing all the bits etc, it also validates
+ # it as valid using the psk etc
+ def decodemsg(msg)
+ body = deserialize(msg.payload)
+
+ should_process_msg?(msg, body[:requestid])
+
+ if validrequest?(body)
+ body[:body] = deserialize(body[:body])
+
+ unless @initiated_by == :client
+ if body[:body].is_a?(Hash)
+ update_secure_property(body, :ssl_ttl, :ttl, "TTL")
+ update_secure_property(body, :ssl_msgtime, :msgtime, "Message Time")
+
+ body[:body] = body[:body][:ssl_msg] if body[:body].include?(:ssl_msg)
+ else
+ unless @config.pluginconf["ssl.enforce_ttl"] == nil
+ raise "Message %s is in an unknown or older security protocol, ignoring" % [request_description(body)]
+ end
+ end
+ end
+
+ return body
+ else
+ nil
+ end
+ end
+
+ # To avoid tampering we turn the origin body into a hash and copy some of the protocol keys
+ # like :ttl and :msg_time into the hash before hashing it.
+ #
+ # This function compares and updates the unhashed ones based on the hashed ones. By
+ # default it enforces matching and presense by raising exceptions, if ssl.enforce_ttl is set
+ # to 0 it will only log warnings about violations
+ def update_secure_property(msg, secure_property, property, description)
+ req = request_description(msg)
+
+ unless @config.pluginconf["ssl.enforce_ttl"] == "0"
+ raise "Request #{req} does not have a secure #{description}" unless msg[:body].include?(secure_property)
+ raise "Request #{req} #{description} does not match encrypted #{description} - possible tampering" unless msg[:body][secure_property] == msg[property]
+ else
+ if msg[:body].include?(secure_property)
+ Log.warn("Request #{req} #{description} does not match encrypted #{description} - possible tampering") unless msg[:body][secure_property] == msg[property]
+ else
+ Log.warn("Request #{req} does not have a secure #{description}") unless msg[:body].include?(secure_property)
+ end
+ end
+
+ msg[property] = msg[:body][secure_property] if msg[:body].include?(secure_property)
+ msg[:body].delete(secure_property)
+ end
+
+ # Encodes a reply
+ def encodereply(sender, msg, requestid, requestcallerid=nil)
+ serialized = serialize(msg)
+ digest = makehash(serialized)
+
+
+ req = create_reply(requestid, sender, serialized)
+ req[:hash] = digest
+
+ serialize(req)
+ end
+
+ # Encodes a request msg
+ def encoderequest(sender, msg, requestid, filter, target_agent, target_collective, ttl=60)
+ req = create_request(requestid, filter, "", @initiated_by, target_agent, target_collective, ttl)
+
+ ssl_msg = {:ssl_msg => msg,
+ :ssl_ttl => ttl,
+ :ssl_msgtime => req[:msgtime]}
+
+ serialized = serialize(ssl_msg)
+ digest = makehash(serialized)
+
+ req[:hash] = digest
+ req[:body] = serialized
+
+ serialize(req)
+ end
+
+ # Checks the SSL signature in the request body
+ def validrequest?(req)
+ message = req[:body]
+ signature = req[:hash]
+
+ Log.debug("Validating request from #{req[:callerid]}")
+
+ if verify(public_key_file(req[:callerid]), signature, message.to_s)
+ @stats.validated
+ return true
+ else
+ @stats.unvalidated
+ raise(SecurityValidationFailed, "Received an invalid signature in message")
+ end
+ end
+
+
+ # sets the caller id to the md5 of the public key
+ def callerid
+ if @initiated_by == :client
+ id = "cert=#{File.basename(client_public_key).gsub(/\.pem$/, '')}"
+ raise "Invalid callerid generated from client public key" unless valid_callerid?(id)
+ else
+ # servers need to set callerid as well, not usually needed but
+ # would be if you're doing registration or auditing or generating
+ # requests for some or other reason
+ id = "cert=#{File.basename(server_public_key).gsub(/\.pem$/, '')}"
+ raise "Invalid callerid generated from server public key" unless valid_callerid?(id)
+ end
+
+ return id
+ end
+
+ private
+ # Serializes a message using the configured encoder
+ def serialize(msg)
+ serializer = @config.pluginconf["ssl_serializer"] || "marshal"
+
+ Log.debug("Serializing using #{serializer}")
+
+ case serializer
+ when "yaml"
+ return YAML.dump(msg)
+ else
+ return Marshal.dump(msg)
+ end
+ end
+
+ # De-Serializes a message using the configured encoder
+ def deserialize(msg)
+ serializer = @config.pluginconf["ssl_serializer"] || "marshal"
+
+ Log.debug("De-Serializing using #{serializer}")
+
+ case serializer
+ when "yaml"
+ return YAML.load(msg)
+ else
+ return Marshal.load(msg)
+ end
+ end
+
+ # Figures out where to get our private key
+ def private_key_file
+ if ENV.include?("MCOLLECTIVE_SSL_PRIVATE")
+ return ENV["MCOLLECTIVE_SSL_PRIVATE"]
+ else
+ if @initiated_by == :node
+ return server_private_key
+ else
+ return client_private_key
+ end
+ end
+ end
+
+ # Figures out the public key to use
+ #
+ # If the node is asking do it based on caller id
+ # If the client is asking just get the node public key
+ def public_key_file(callerid = nil)
+ if @initiated_by == :client
+ return server_public_key
+ else
+ if callerid =~ /cert=([\w\.\-]+)/
+ cid = $1
+
+ if File.exist?("#{client_cert_dir}/#{cid}.pem")
+ return "#{client_cert_dir}/#{cid}.pem"
+ else
+ raise("Could not find a public key for #{cid} in #{client_cert_dir}/#{cid}.pem")
+ end
+ else
+ raise("Caller id is not in the expected format")
+ end
+ end
+ end
+
+ # Figures out the client private key either from MCOLLECTIVE_SSL_PRIVATE or the
+ # plugin.ssl_client_private config option
+ def client_private_key
+ return ENV["MCOLLECTIVE_SSL_PRIVATE"] if ENV.include?("MCOLLECTIVE_SSL_PRIVATE")
+
+ raise("No plugin.ssl_client_private configuration option specified") unless @config.pluginconf.include?("ssl_client_private")
+
+ return @config.pluginconf["ssl_client_private"]
+ end
+
+ # Figures out the client public key either from MCOLLECTIVE_SSL_PUBLIC or the
+ # plugin.ssl_client_public config option
+ def client_public_key
+ return ENV["MCOLLECTIVE_SSL_PUBLIC"] if ENV.include?("MCOLLECTIVE_SSL_PUBLIC")
+
+ raise("No plugin.ssl_client_public configuration option specified") unless @config.pluginconf.include?("ssl_client_public")
+
+ return @config.pluginconf["ssl_client_public"]
+ end
+
+ # Figures out the server private key from the plugin.ssl_server_private config option
+ def server_private_key
+ raise("No plugin.ssl_server_private configuration option specified") unless @config.pluginconf.include?("ssl_server_private")
+ @config.pluginconf["ssl_server_private"]
+ end
+
+ # Figures out the server public key from the plugin.ssl_server_public config option
+ def server_public_key
+ raise("No ssl_server_public configuration option specified") unless @config.pluginconf.include?("ssl_server_public")
+ return @config.pluginconf["ssl_server_public"]
+ end
+
+ # Figures out where to get client public certs from the plugin.ssl_client_cert_dir config option
+ def client_cert_dir
+ raise("No plugin.ssl_client_cert_dir configuration option specified") unless @config.pluginconf.include?("ssl_client_cert_dir")
+ @config.pluginconf["ssl_client_cert_dir"]
+ end
+
+ # Retrieves the value of plugin.psk and builds a hash with it and the passed body
+ def makehash(body)
+ Log.debug("Creating message hash using #{private_key_file}")
+
+ sign(private_key_file, body.to_s)
+ end
+
+ # Code adapted from http://github.com/adamcooke/basicssl
+ # signs a message
+ def sign(key, string)
+ SSL.new(nil, key).sign(string, true)
+ end
+
+ # verifies a signature
+ def verify(key, signature, string)
+ SSL.new(key).verify_signature(signature, string, true)
+ end
+
+ def request_description(msg)
+ "%s from %s@%s" % [msg[:requestid], msg[:callerid], msg[:senderid]]
+ end
+ end
+ end
+end
Code Review / packages / precise / mcollective.git / blobdiff