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ruby-net-ldap/lib/net/ldap.rb
blackhedd bc54a9c826 added a compiler for ASN/BER syntax, avoids interpreting it for 
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2006-09-02 16:48:07 +00:00

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# $Id$
#
# Net::LDAP for Ruby
#
#
# Copyright (C) 2006 by Francis Cianfrocca. All Rights Reserved.
#
# Written and maintained by Francis Cianfrocca, gmail: garbagecat10.
#
# This program is free software.
# You may re-distribute and/or modify this program under the same terms
# as Ruby itself: Ruby Distribution License or GNU General Public License.
#
#
# See Net::LDAP for documentation and usage samples.
#
require 'socket'
require 'ostruct'
begin
require 'openssl'
$net_ldap_openssl_available = true
rescue LoadError
end
require 'net/ber'
require 'net/ldap/pdu'
require 'net/ldap/filter'
require 'net/ldap/dataset'
require 'net/ldap/psw'
require 'net/ldap/entry'
module Net
# == Net::LDAP
#
# This library provides a pure-Ruby implementation of the
# LDAP client protocol, per RFC-2251.
# It can be used to access any server which implements the
# LDAP protocol.
#
# Net::LDAP is intended to provide full LDAP functionality
# while hiding the more arcane aspects
# the LDAP protocol itself, and thus presenting as Ruby-like
# a programming interface as possible.
#
# == Quick-start for the Impatient
# === Quick Example of a user-authentication against an LDAP directory:
#
# require 'rubygems'
# require 'net/ldap'
#
# ldap = Net::LDAP.new
# ldap.host = your_server_ip_address
# ldap.port = 389
# ldap.auth "joe_user", "opensesame"
# if ldap.bind
# # authentication succeeded
# else
# # authentication failed
# end
#
#
# === Quick Example of a search against an LDAP directory:
#
# require 'rubygems'
# require 'net/ldap'
#
# ldap = Net::LDAP.new :host => server_ip_address,
# :port => 389,
# :auth => {
# :method => :simple,
# :username => "cn=manager,dc=example,dc=com",
# :password => "opensesame"
# }
#
# filter = Net::LDAP::Filter.eq( "cn", "George*" )
# treebase = "dc=example,dc=com"
#
# ldap.search( :base => treebase, :filter => filter ) do |entry|
# puts "DN: #{entry.dn}"
# entry.each do |attribute, values|
# puts " #{attribute}:"
# values.each do |value|
# puts " --->#{value}"
# end
# end
# end
#
# p ldap.get_operation_result
#
#
# == A Brief Introduction to LDAP
#
# We're going to provide a quick, informal introduction to LDAP
# terminology and
# typical operations. If you're comfortable with this material, skip
# ahead to "How to use Net::LDAP." If you want a more rigorous treatment
# of this material, we recommend you start with the various IETF and ITU
# standards that relate to LDAP.
#
# === Entities
# LDAP is an Internet-standard protocol used to access directory servers.
# The basic search unit is the <i>entity,</i> which corresponds to
# a person or other domain-specific object.
# A directory service which supports the LDAP protocol typically
# stores information about a number of entities.
#
# === Principals
# LDAP servers are typically used to access information about people,
# but also very often about such items as printers, computers, and other
# resources. To reflect this, LDAP uses the term <i>entity,</i> or less
# commonly, <i>principal,</i> to denote its basic data-storage unit.
#
#
# === Distinguished Names
# In LDAP's view of the world,
# an entity is uniquely identified by a globally-unique text string
# called a <i>Distinguished Name,</i> originally defined in the X.400
# standards from which LDAP is ultimately derived.
# Much like a DNS hostname, a DN is a "flattened" text representation
# of a string of tree nodes. Also like DNS (and unlike Java package
# names), a DN expresses a chain of tree-nodes written from left to right
# in order from the most-resolved node to the most-general one.
#
# If you know the DN of a person or other entity, then you can query
# an LDAP-enabled directory for information (attributes) about the entity.
# Alternatively, you can query the directory for a list of DNs matching
# a set of criteria that you supply.
#
# === Attributes
#
# In the LDAP view of the world, a DN uniquely identifies an entity.
# Information about the entity is stored as a set of <i>Attributes.</i>
# An attribute is a text string which is associated with zero or more
# values. Most LDAP-enabled directories store a well-standardized
# range of attributes, and constrain their values according to standard
# rules.
#
# A good example of an attribute is <tt>sn,</tt> which stands for "Surname."
# This attribute is generally used to store a person's surname, or last name.
# Most directories enforce the standard convention that
# an entity's <tt>sn</tt> attribute have <i>exactly one</i> value. In LDAP
# jargon, that means that <tt>sn</tt> must be <i>present</i> and
# <i>single-valued.</i>
#
# Another attribute is <tt>mail,</tt> which is used to store email addresses.
# (No, there is no attribute called "email," perhaps because X.400 terminology
# predates the invention of the term <i>email.</i>) <tt>mail</tt> differs
# from <tt>sn</tt> in that most directories permit any number of values for the
# <tt>mail</tt> attribute, including zero.
#
#
# === Tree-Base
# We said above that X.400 Distinguished Names are <i>globally unique.</i>
# In a manner reminiscent of DNS, LDAP supposes that each directory server
# contains authoritative attribute data for a set of DNs corresponding
# to a specific sub-tree of the (notional) global directory tree.
# This subtree is generally configured into a directory server when it is
# created. It matters for this discussion because most servers will not
# allow you to query them unless you specify a correct tree-base.
#
# Let's say you work for the engineering department of Big Company, Inc.,
# whose internet domain is bigcompany.com. You may find that your departmental
# directory is stored in a server with a defined tree-base of
# ou=engineering,dc=bigcompany,dc=com
# You will need to supply this string as the <i>tree-base</i> when querying this
# directory. (Ou is a very old X.400 term meaning "organizational unit."
# Dc is a more recent term meaning "domain component.")
#
# === LDAP Versions
# (stub, discuss v2 and v3)
#
# === LDAP Operations
# The essential operations are: #bind, #search, #add, #modify, #delete, and #rename.
# ==== Bind
# #bind supplies a user's authentication credentials to a server, which in turn verifies
# or rejects them. There is a range of possibilities for credentials, but most directories
# support a simple username and password authentication.
#
# Taken by itself, #bind can be used to authenticate a user against information
# stored in a directory, for example to permit or deny access to some other resource.
# In terms of the other LDAP operations, most directories require a successful #bind to
# be performed before the other operations will be permitted. Some servers permit certain
# operations to be performed with an "anonymous" binding, meaning that no credentials are
# presented by the user. (We're glossing over a lot of platform-specific detail here.)
#
# ==== Search
# Calling #search against the directory involves specifying a treebase, a set of <i>search filters,</i>
# and a list of attribute values.
# The filters specify ranges of possible values for particular attributes. Multiple
# filters can be joined together with AND, OR, and NOT operators.
# A server will respond to a #search by returning a list of matching DNs together with a
# set of attribute values for each entity, depending on what attributes the search requested.
#
# ==== Add
# #add specifies a new DN and an initial set of attribute values. If the operation
# succeeds, a new entity with the corresponding DN and attributes is added to the directory.
#
# ==== Modify
# #modify specifies an entity DN, and a list of attribute operations. #modify is used to change
# the attribute values stored in the directory for a particular entity.
# #modify may add or delete attributes (which are lists of values) or it change attributes by
# adding to or deleting from their values.
# Net::LDAP provides three easier methods to modify an entry's attribute values:
# #add_attribute, #replace_attribute, and #delete_attribute.
#
# ==== Delete
# #delete specifies an entity DN. If it succeeds, the entity and all its attributes
# is removed from the directory.
#
# ==== Rename (or Modify RDN)
# #rename (or #modify_rdn) is an operation added to version 3 of the LDAP protocol. It responds to
# the often-arising need to change the DN of an entity without discarding its attribute values.
# In earlier LDAP versions, the only way to do this was to delete the whole entity and add it
# again with a different DN.
#
# #rename works by taking an "old" DN (the one to change) and a "new RDN," which is the left-most
# part of the DN string. If successful, #rename changes the entity DN so that its left-most
# node corresponds to the new RDN given in the request. (RDN, or "relative distinguished name,"
# denotes a single tree-node as expressed in a DN, which is a chain of tree nodes.)
#
# == How to use Net::LDAP
#
# To access Net::LDAP functionality in your Ruby programs, start by requiring
# the library:
#
# require 'net/ldap'
#
# If you installed the Gem version of Net::LDAP, and depending on your version of
# Ruby and rubygems, you _may_ also need to require rubygems explicitly:
#
# require 'rubygems'
# require 'net/ldap'
#
# Most operations with Net::LDAP start by instantiating a Net::LDAP object.
# The constructor for this object takes arguments specifying the network location
# (address and port) of the LDAP server, and also the binding (authentication)
# credentials, typically a username and password.
# Given an object of class Net:LDAP, you can then perform LDAP operations by calling
# instance methods on the object. These are documented with usage examples below.
#
# The Net::LDAP library is designed to be very disciplined about how it makes network
# connections to servers. This is different from many of the standard native-code
# libraries that are provided on most platforms, which share bloodlines with the
# original Netscape/Michigan LDAP client implementations. These libraries sought to
# insulate user code from the workings of the network. This is a good idea of course,
# but the practical effect has been confusing and many difficult bugs have been caused
# by the opacity of the native libraries, and their variable behavior across platforms.
#
# In general, Net::LDAP instance methods which invoke server operations make a connection
# to the server when the method is called. They execute the operation (typically binding first)
# and then disconnect from the server. The exception is Net::LDAP#open, which makes a connection
# to the server and then keeps it open while it executes a user-supplied block. Net::LDAP#open
# closes the connection on completion of the block.
#
class LDAP
class LdapError < Exception; end
VERSION = "0.1.0"
SearchScope_BaseObject = 0
SearchScope_SingleLevel = 1
SearchScope_WholeSubtree = 2
SearchScopes = [SearchScope_BaseObject, SearchScope_SingleLevel, SearchScope_WholeSubtree]
AsnSyntax = BER.compile_syntax({
:application => {
:constructed => {
0 => :array, # BindRequest
1 => :array, # BindResponse
2 => :array, # UnbindRequest
3 => :array, # SearchRequest
4 => :array, # SearchData
5 => :array, # SearchResult
6 => :array, # ModifyRequest
7 => :array, # ModifyResponse
8 => :array, # AddRequest
9 => :array, # AddResponse
10 => :array, # DelRequest
11 => :array, # DelResponse
12 => :array, # ModifyRdnRequest
13 => :array, # ModifyRdnResponse
14 => :array, # CompareRequest
15 => :array, # CompareResponse
16 => :array, # AbandonRequest
19 => :array, # SearchResultReferral
24 => :array, # Unsolicited Notification
}
},
:context_specific => {
:primitive => {
0 => :string, # password
1 => :string, # Kerberos v4
2 => :string, # Kerberos v5
},
:constructed => {
0 => :array, # RFC-2251 Control
3 => :array, # Seach referral
}
}
})
DefaultHost = "127.0.0.1"
DefaultPort = 389
DefaultAuth = {:method => :anonymous}
DefaultTreebase = "dc=com"
ResultStrings = {
0 => "Success",
1 => "Operations Error",
2 => "Protocol Error",
3 => "Time Limit Exceeded",
4 => "Size Limit Exceeded",
12 => "Unavailable crtical extension",
16 => "No Such Attribute",
17 => "Undefined Attribute Type",
20 => "Attribute or Value Exists",
32 => "No Such Object",
34 => "Invalid DN Syntax",
48 => "Invalid DN Syntax",
48 => "Inappropriate Authentication",
49 => "Invalid Credentials",
50 => "Insufficient Access Rights",
51 => "Busy",
52 => "Unavailable",
53 => "Unwilling to perform",
65 => "Object Class Violation",
68 => "Entry Already Exists"
}
module LdapControls
PagedResults = "1.2.840.113556.1.4.319" # Microsoft evil from RFC 2696
end
#
# LDAP::result2string
#
def LDAP::result2string code # :nodoc:
ResultStrings[code] || "unknown result (#{code})"
end
attr_accessor :host, :port, :base
# Instantiate an object of type Net::LDAP to perform directory operations.
# This constructor takes a Hash containing arguments, all of which are either optional or may be specified later with other methods as described below. The following arguments
# are supported:
# * :host => the LDAP server's IP-address (default 127.0.0.1)
# * :port => the LDAP server's TCP port (default 389)
# * :auth => a Hash containing authorization parameters. Currently supported values include:
# {:method => :anonymous} and
# {:method => :simple, :username => your_user_name, :password => your_password }
# The password parameter may be a Proc that returns a String.
# * :base => a default treebase parameter for searches performed against the LDAP server. If you don't give this value, then each call to #search must specify a treebase parameter. If you do give this value, then it will be used in subsequent calls to #search that do not specify a treebase. If you give a treebase value in any particular call to #search, that value will override any treebase value you give here.
# * :encryption => specifies the encryption to be used in communicating with the LDAP server. The value is either a Hash containing additional parameters, or the Symbol :simple_tls, which is equivalent to specifying the Hash {:method => :simple_tls}. There is a fairly large range of potential values that may be given for this parameter. See #encryption for details.
#
# Instantiating a Net::LDAP object does <i>not</i> result in network traffic to
# the LDAP server. It simply stores the connection and binding parameters in the
# object.
#
def initialize args = {}
@host = args[:host] || DefaultHost
@port = args[:port] || DefaultPort
@verbose = false # Make this configurable with a switch on the class.
@auth = args[:auth] || DefaultAuth
@base = args[:base] || DefaultTreebase
encryption args[:encryption] # may be nil
if pr = @auth[:password] and pr.respond_to?(:call)
@auth[:password] = pr.call
end
# This variable is only set when we are created with LDAP::open.
# All of our internal methods will connect using it, or else
# they will create their own.
@open_connection = nil
end
# Convenience method to specify authentication credentials to the LDAP
# server. Currently supports simple authentication requiring
# a username and password.
#
# Observe that on most LDAP servers,
# the username is a complete DN. However, with A/D, it's often possible
# to give only a user-name rather than a complete DN. In the latter
# case, beware that many A/D servers are configured to permit anonymous
# (uncredentialled) binding, and will silently accept your binding
# as anonymous if you give an unrecognized username. This is not usually
# what you want. (See #get_operation_result.)
#
# <b>Important:</b> The password argument may be a Proc that returns a string.
# This makes it possible for you to write client programs that solicit
# passwords from users or from other data sources without showing them
# in your code or on command lines.
#
# require 'net/ldap'
#
# ldap = Net::LDAP.new
# ldap.host = server_ip_address
# ldap.authenticate "cn=Your Username,cn=Users,dc=example,dc=com", "your_psw"
#
# Alternatively (with a password block):
#
# require 'net/ldap'
#
# ldap = Net::LDAP.new
# ldap.host = server_ip_address
# psw = proc { your_psw_function }
# ldap.authenticate "cn=Your Username,cn=Users,dc=example,dc=com", psw
#
def authenticate username, password
password = password.call if password.respond_to?(:call)
@auth = {:method => :simple, :username => username, :password => password}
end
alias_method :auth, :authenticate
# Convenience method to specify encryption characteristics for connections
# to LDAP servers. Called implicitly by #new and #open, but may also be called
# by user code if desired.
# The single argument is generally a Hash (but see below for convenience alternatives).
# This implementation is currently a stub, supporting only a few encryption
# alternatives. As additional capabilities are added, more configuration values
# will be added here.
#
# Currently, the only supported argument is {:method => :simple_tls}.
# (Equivalently, you may pass the symbol :simple_tls all by itself, without
# enclosing it in a Hash.)
#
# The :simple_tls encryption method encrypts <i>all</i> communications with the LDAP
# server.
# It completely establishes SSL/TLS encryption with the LDAP server
# before any LDAP-protocol data is exchanged.
# There is no plaintext negotiation and no special encryption-request controls
# are sent to the server.
# <i>The :simple_tls option is the simplest, easiest way to encrypt communications
# between Net::LDAP and LDAP servers.</i>
# It's intended for cases where you have an implicit level of trust in the authenticity
# of the LDAP server. No validation of the LDAP server's SSL certificate is
# performed. This means that :simple_tls will not produce errors if the LDAP
# server's encryption certificate is not signed by a well-known Certification
# Authority.
# If you get communications or protocol errors when using this option, check
# with your LDAP server administrator. Pay particular attention to the TCP port
# you are connecting to. It's impossible for an LDAP server to support plaintext
# LDAP communications and <i>simple TLS</i> connections on the same port.
# The standard TCP port for unencrypted LDAP connections is 389, but the standard
# port for simple-TLS encrypted connections is 636. Be sure you are using the
# correct port.
#
# <i>[Note: a future version of Net::LDAP will support the STARTTLS LDAP control,
# which will enable encrypted communications on the same TCP port used for
# unencrypted connections.]</i>
#
def encryption args
if args == :simple_tls
args = {:method => :simple_tls}
end
@encryption = args
end
# #open takes the same parameters as #new. #open makes a network connection to the
# LDAP server and then passes a newly-created Net::LDAP object to the caller-supplied block.
# Within the block, you can call any of the instance methods of Net::LDAP to
# perform operations against the LDAP directory. #open will perform all the
# operations in the user-supplied block on the same network connection, which
# will be closed automatically when the block finishes.
#
# # (PSEUDOCODE)
# auth = {:method => :simple, :username => username, :password => password}
# Net::LDAP.open( :host => ipaddress, :port => 389, :auth => auth ) do |ldap|
# ldap.search( ... )
# ldap.add( ... )
# ldap.modify( ... )
# end
#
def LDAP::open args
ldap1 = LDAP.new args
ldap1.open {|ldap| yield ldap }
end
# Returns a meaningful result any time after
# a protocol operation (#bind, #search, #add, #modify, #rename, #delete)
# has completed.
# It returns an #OpenStruct containing an LDAP result code (0 means success),
# and a human-readable string.
# unless ldap.bind
# puts "Result: #{ldap.get_operation_result.code}"
# puts "Message: #{ldap.get_operation_result.message}"
# end
#
def get_operation_result
os = OpenStruct.new
if @result
os.code = @result
else
os.code = 0
end
os.message = LDAP.result2string( os.code )
os
end
# Opens a network connection to the server and then
# passes <tt>self</tt> to the caller-supplied block. The connection is
# closed when the block completes. Used for executing multiple
# LDAP operations without requiring a separate network connection
# (and authentication) for each one.
# <i>Note:</i> You do not need to log-in or "bind" to the server. This will
# be done for you automatically.
# For an even simpler approach, see the class method Net::LDAP#open.
#
# # (PSEUDOCODE)
# auth = {:method => :simple, :username => username, :password => password}
# ldap = Net::LDAP.new( :host => ipaddress, :port => 389, :auth => auth )
# ldap.open do |ldap|
# ldap.search( ... )
# ldap.add( ... )
# ldap.modify( ... )
# end
#--
# First we make a connection and then a binding, but we don't
# do anything with the bind results.
# We then pass self to the caller's block, where he will execute
# his LDAP operations. Of course they will all generate auth failures
# if the bind was unsuccessful.
def open
raise LdapError.new( "open already in progress" ) if @open_connection
@open_connection = Connection.new( :host => @host, :port => @port, :encryption => @encryption )
@open_connection.bind @auth
yield self
@open_connection.close
@open_connection = nil
end
# Searches the LDAP directory for directory entries.
# Takes a hash argument with parameters. Supported parameters include:
# * :base (a string specifying the tree-base for the search);
# * :filter (an object of type Net::LDAP::Filter, defaults to objectclass=*);
# * :attributes (a string or array of strings specifying the LDAP attributes to return from the server);
# * :return_result (a boolean specifying whether to return a result set).
# * :attributes_only (a boolean flag, defaults false)
# * :scope (one of: Net::LDAP::SearchScope_BaseObject, Net::LDAP::SearchScope_SingleLevel, Net::LDAP::SearchScope_WholeSubtree. Default is WholeSubtree.)
#
# #search queries the LDAP server and passes <i>each entry</i> to the
# caller-supplied block, as an object of type Net::LDAP::Entry.
# If the search returns 1000 entries, the block will
# be called 1000 times. If the search returns no entries, the block will
# not be called.
#
#--
# ORIGINAL TEXT, replaced 04May06.
# #search returns either a result-set or a boolean, depending on the
# value of the <tt>:return_result</tt> argument. The default behavior is to return
# a result set, which is a hash. Each key in the hash is a string specifying
# the DN of an entry. The corresponding value for each key is a Net::LDAP::Entry object.
# If you request a result set and #search fails with an error, it will return nil.
# Call #get_operation_result to get the error information returned by
# the LDAP server.
#++
# #search returns either a result-set or a boolean, depending on the
# value of the <tt>:return_result</tt> argument. The default behavior is to return
# a result set, which is an Array of objects of class Net::LDAP::Entry.
# If you request a result set and #search fails with an error, it will return nil.
# Call #get_operation_result to get the error information returned by
# the LDAP server.
#
# When <tt>:return_result => false,</tt> #search will
# return only a Boolean, to indicate whether the operation succeeded. This can improve performance
# with very large result sets, because the library can discard each entry from memory after
# your block processes it.
#
#
# treebase = "dc=example,dc=com"
# filter = Net::LDAP::Filter.eq( "mail", "a*.com" )
# attrs = ["mail", "cn", "sn", "objectclass"]
# ldap.search( :base => treebase, :filter => filter, :attributes => attrs, :return_result => false ) do |entry|
# puts "DN: #{entry.dn}"
# entry.each do |attr, values|
# puts ".......#{attr}:"
# values.each do |value|
# puts " #{value}"
# end
# end
# end
#
#--
# This is a re-implementation of search that replaces the
# original one (now renamed searchx and possibly destined to go away).
# The difference is that we return a dataset (or nil) from the
# call, and pass _each entry_ as it is received from the server
# to the caller-supplied block. This will probably make things
# far faster as we can do useful work during the network latency
# of the search. The downside is that we have no access to the
# whole set while processing the blocks, so we can't do stuff
# like sort the DNs until after the call completes.
# It's also possible that this interacts badly with server timeouts.
# We'll have to ensure that something reasonable happens if
# the caller has processed half a result set when we throw a timeout
# error.
# Another important difference is that we return a result set from
# this method rather than a T/F indication.
# Since this can be very heavy-weight, we define an argument flag
# that the caller can set to suppress the return of a result set,
# if he's planning to process every entry as it comes from the server.
#
# REINTERPRETED the result set, 04May06. Originally this was a hash
# of entries keyed by DNs. But let's get away from making users
# handle DNs. Change it to a plain array. Eventually we may
# want to return a Dataset object that delegates to an internal
# array, so we can provide sort methods and what-not.
#
def search args = {}
args[:base] ||= @base
result_set = (args and args[:return_result] == false) ? nil : []
if @open_connection
@result = @open_connection.search( args ) {|entry|
result_set << entry if result_set
yield( entry ) if block_given?
}
else
@result = 0
conn = Connection.new( :host => @host, :port => @port, :encryption => @encryption )
if (@result = conn.bind( args[:auth] || @auth )) == 0
@result = conn.search( args ) {|entry|
result_set << entry if result_set
yield( entry ) if block_given?
}
end
conn.close
end
@result == 0 and result_set
end
# #bind connects to an LDAP server and requests authentication
# based on the <tt>:auth</tt> parameter passed to #open or #new.
# It takes no parameters.
#
# User code does not need to call #bind directly. It will be called
# implicitly by the library whenever you invoke an LDAP operation,
# such as #search or #add.
#
# It is useful, however, to call #bind in your own code when the
# only operation you intend to perform against the directory is
# to validate a login credential. #bind returns true or false
# to indicate whether the binding was successful. Reasons for
# failure include malformed or unrecognized usernames and
# incorrect passwords. Use #get_operation_result to find out
# what happened in case of failure.
#
# Here's a typical example using #bind to authenticate a
# credential which was (perhaps) solicited from the user of a
# web site:
#
# require 'net/ldap'
# ldap = Net::LDAP.new
# ldap.host = your_server_ip_address
# ldap.port = 389
# ldap.auth your_user_name, your_user_password
# if ldap.bind
# # authentication succeeded
# else
# # authentication failed
# p ldap.get_operation_result
# end
#
# You don't have to create a new instance of Net::LDAP every time
# you perform a binding in this way. If you prefer, you can cache the Net::LDAP object
# and re-use it to perform subsequent bindings, <i>provided</i> you call
# #auth to specify a new credential before calling #bind. Otherwise, you'll
# just re-authenticate the previous user! (You don't need to re-set
# the values of #host and #port.) As noted in the documentation for #auth,
# the password parameter can be a Ruby Proc instead of a String.
#
#--
# If there is an @open_connection, then perform the bind
# on it. Otherwise, connect, bind, and disconnect.
# The latter operation is obviously useful only as an auth check.
#
def bind auth=@auth
if @open_connection
@result = @open_connection.bind auth
else
conn = Connection.new( :host => @host, :port => @port , :encryption => @encryption)
@result = conn.bind @auth
conn.close
end
@result == 0
end
#
# #bind_as is for testing authentication credentials.
#
# As described under #bind, most LDAP servers require that you supply a complete DN
# as a binding-credential, along with an authenticator such as a password.
# But for many applications (such as authenticating users to a Rails application),
# you often don't have a full DN to identify the user. You usually get a simple
# identifier like a username or an email address, along with a password.
# #bind_as allows you to authenticate these user-identifiers.
#
# #bind_as is a combination of a search and an LDAP binding. First, it connects and
# binds to the directory as normal. Then it searches the directory for an entry
# corresponding to the email address, username, or other string that you supply.
# If the entry exists, then #bind_as will <b>re-bind</b> as that user with the
# password (or other authenticator) that you supply.
#
# #bind_as takes the same parameters as #search, <i>with the addition of an
# authenticator.</i> Currently, this authenticator must be <tt>:password</tt>.
# Its value may be either a String, or a +proc+ that returns a String.
# #bind_as returns +false+ on failure. On success, it returns a result set,
# just as #search does. This result set is an Array of objects of
# type Net::LDAP::Entry. It contains the directory attributes corresponding to
# the user. (Just test whether the return value is logically true, if you don't
# need this additional information.)
#
# Here's how you would use #bind_as to authenticate an email address and password:
#
# require 'net/ldap'
#
# user,psw = "joe_user@yourcompany.com", "joes_psw"
#
# ldap = Net::LDAP.new
# ldap.host = "192.168.0.100"
# ldap.port = 389
# ldap.auth "cn=manager,dc=yourcompany,dc=com", "topsecret"
#
# result = ldap.bind_as(
# :base => "dc=yourcompany,dc=com",
# :filter => "(mail=#{user})",
# :password => psw
# )
# if result
# puts "Authenticated #{result.first.dn}"
# else
# puts "Authentication FAILED."
# end
def bind_as args={}
result = false
open {|me|
rs = search args
if rs and rs.first and dn = rs.first.dn
password = args[:password]
password = password.call if password.respond_to?(:call)
result = rs if bind :method => :simple, :username => dn, :password => password
end
}
result
end
# Adds a new entry to the remote LDAP server.
# Supported arguments:
# :dn :: Full DN of the new entry
# :attributes :: Attributes of the new entry.
#
# The attributes argument is supplied as a Hash keyed by Strings or Symbols
# giving the attribute name, and mapping to Strings or Arrays of Strings
# giving the actual attribute values. Observe that most LDAP directories
# enforce schema constraints on the attributes contained in entries.
# #add will fail with a server-generated error if your attributes violate
# the server-specific constraints.
# Here's an example:
#
# dn = "cn=George Smith,ou=people,dc=example,dc=com"
# attr = {
# :cn => "George Smith",
# :objectclass => ["top", "inetorgperson"],
# :sn => "Smith",
# :mail => "gsmith@example.com"
# }
# Net::LDAP.open (:host => host) do |ldap|
# ldap.add( :dn => dn, :attributes => attr )
# end
#
def add args
if @open_connection
@result = @open_connection.add( args )
else
@result = 0
conn = Connection.new( :host => @host, :port => @port, :encryption => @encryption)
if (@result = conn.bind( args[:auth] || @auth )) == 0
@result = conn.add( args )
end
conn.close
end
@result == 0
end
# Modifies the attribute values of a particular entry on the LDAP directory.
# Takes a hash with arguments. Supported arguments are:
# :dn :: (the full DN of the entry whose attributes are to be modified)
# :operations :: (the modifications to be performed, detailed next)
#
# This method returns True or False to indicate whether the operation
# succeeded or failed, with extended information available by calling
# #get_operation_result.
#
# Also see #add_attribute, #replace_attribute, or #delete_attribute, which
# provide simpler interfaces to this functionality.
#
# The LDAP protocol provides a full and well thought-out set of operations
# for changing the values of attributes, but they are necessarily somewhat complex
# and not always intuitive. If these instructions are confusing or incomplete,
# please send us email or create a bug report on rubyforge.
#
# The :operations parameter to #modify takes an array of operation-descriptors.
# Each individual operation is specified in one element of the array, and
# most LDAP servers will attempt to perform the operations in order.
#
# Each of the operations appearing in the Array must itself be an Array
# with exactly three elements:
# an operator:: must be :add, :replace, or :delete
# an attribute name:: the attribute name (string or symbol) to modify
# a value:: either a string or an array of strings.
#
# The :add operator will, unsurprisingly, add the specified values to
# the specified attribute. If the attribute does not already exist,
# :add will create it. Most LDAP servers will generate an error if you
# try to add a value that already exists.
#
# :replace will erase the current value(s) for the specified attribute,
# if there are any, and replace them with the specified value(s).
#
# :delete will remove the specified value(s) from the specified attribute.
# If you pass nil, an empty string, or an empty array as the value parameter
# to a :delete operation, the _entire_ _attribute_ will be deleted, along
# with all of its values.
#
# For example:
#
# dn = "mail=modifyme@example.com,ou=people,dc=example,dc=com"
# ops = [
# [:add, :mail, "aliasaddress@example.com"],
# [:replace, :mail, ["newaddress@example.com", "newalias@example.com"]],
# [:delete, :sn, nil]
# ]
# ldap.modify :dn => dn, :operations => ops
#
# <i>(This example is contrived since you probably wouldn't add a mail
# value right before replacing the whole attribute, but it shows that order
# of execution matters. Also, many LDAP servers won't let you delete SN
# because that would be a schema violation.)</i>
#
# It's essential to keep in mind that if you specify more than one operation in
# a call to #modify, most LDAP servers will attempt to perform all of the operations
# in the order you gave them.
# This matters because you may specify operations on the
# same attribute which must be performed in a certain order.
#
# Most LDAP servers will _stop_ processing your modifications if one of them
# causes an error on the server (such as a schema-constraint violation).
# If this happens, you will probably get a result code from the server that
# reflects only the operation that failed, and you may or may not get extended
# information that will tell you which one failed. #modify has no notion
# of an atomic transaction. If you specify a chain of modifications in one
# call to #modify, and one of them fails, the preceding ones will usually
# not be "rolled back," resulting in a partial update. This is a limitation
# of the LDAP protocol, not of Net::LDAP.
#
# The lack of transactional atomicity in LDAP means that you're usually
# better off using the convenience methods #add_attribute, #replace_attribute,
# and #delete_attribute, which are are wrappers over #modify. However, certain
# LDAP servers may provide concurrency semantics, in which the several operations
# contained in a single #modify call are not interleaved with other
# modification-requests received simultaneously by the server.
# It bears repeating that this concurrency does _not_ imply transactional
# atomicity, which LDAP does not provide.
#
def modify args
if @open_connection
@result = @open_connection.modify( args )
else
@result = 0
conn = Connection.new( :host => @host, :port => @port, :encryption => @encryption )
if (@result = conn.bind( args[:auth] || @auth )) == 0
@result = conn.modify( args )
end
conn.close
end
@result == 0
end
# Add a value to an attribute.
# Takes the full DN of the entry to modify,
# the name (Symbol or String) of the attribute, and the value (String or
# Array). If the attribute does not exist (and there are no schema violations),
# #add_attribute will create it with the caller-specified values.
# If the attribute already exists (and there are no schema violations), the
# caller-specified values will be _added_ to the values already present.
#
# Returns True or False to indicate whether the operation
# succeeded or failed, with extended information available by calling
# #get_operation_result. See also #replace_attribute and #delete_attribute.
#
# dn = "cn=modifyme,dc=example,dc=com"
# ldap.add_attribute dn, :mail, "newmailaddress@example.com"
#
def add_attribute dn, attribute, value
modify :dn => dn, :operations => [[:add, attribute, value]]
end
# Replace the value of an attribute.
# #replace_attribute can be thought of as equivalent to calling #delete_attribute
# followed by #add_attribute. It takes the full DN of the entry to modify,
# the name (Symbol or String) of the attribute, and the value (String or
# Array). If the attribute does not exist, it will be created with the
# caller-specified value(s). If the attribute does exist, its values will be
# _discarded_ and replaced with the caller-specified values.
#
# Returns True or False to indicate whether the operation
# succeeded or failed, with extended information available by calling
# #get_operation_result. See also #add_attribute and #delete_attribute.
#
# dn = "cn=modifyme,dc=example,dc=com"
# ldap.replace_attribute dn, :mail, "newmailaddress@example.com"
#
def replace_attribute dn, attribute, value
modify :dn => dn, :operations => [[:replace, attribute, value]]
end
# Delete an attribute and all its values.
# Takes the full DN of the entry to modify, and the
# name (Symbol or String) of the attribute to delete.
#
# Returns True or False to indicate whether the operation
# succeeded or failed, with extended information available by calling
# #get_operation_result. See also #add_attribute and #replace_attribute.
#
# dn = "cn=modifyme,dc=example,dc=com"
# ldap.delete_attribute dn, :mail
#
def delete_attribute dn, attribute
modify :dn => dn, :operations => [[:delete, attribute, nil]]
end
# Rename an entry on the remote DIS by changing the last RDN of its DN.
# _Documentation_ _stub_
#
def rename args
if @open_connection
@result = @open_connection.rename( args )
else
@result = 0
conn = Connection.new( :host => @host, :port => @port, :encryption => @encryption )
if (@result = conn.bind( args[:auth] || @auth )) == 0
@result = conn.rename( args )
end
conn.close
end
@result == 0
end
# modify_rdn is an alias for #rename.
def modify_rdn args
rename args
end
# Delete an entry from the LDAP directory.
# Takes a hash of arguments.
# The only supported argument is :dn, which must
# give the complete DN of the entry to be deleted.
# Returns True or False to indicate whether the delete
# succeeded. Extended status information is available by
# calling #get_operation_result.
#
# dn = "mail=deleteme@example.com,ou=people,dc=example,dc=com"
# ldap.delete :dn => dn
#
def delete args
if @open_connection
@result = @open_connection.delete( args )
else
@result = 0
conn = Connection.new( :host => @host, :port => @port, :encryption => @encryption )
if (@result = conn.bind( args[:auth] || @auth )) == 0
@result = conn.delete( args )
end
conn.close
end
@result == 0
end
# (Experimental, subject to change).
# Return the rootDSE record from the LDAP server as a Net::LDAP::Entry, or an
# empty Entry if the server doesn't return the record.
#--
# cf. RFC4512 graf 5.1.
# Note that the rootDSE record we return on success has an empty DN, which is correct.
# On failure, the empty Entry will have a nil DN. There's no real reason for that,
# so it can be changed if desired.
# The funky number-disagreements in the set of attribute names is correct per the RFC.
#
def search_root_dse
rs = search(
:base=>"",
:scope=>SearchScope_BaseObject,
:attributes=>[:namingContexts,:supportedLdapVersion,:altServer,:supportedControl,:supportedExtension,:supportedFeatures,:supportedSASLMechanisms]
)
(rs and rs.first) or Entry.new
end
end # class LDAP
class LDAP
# This is a private class used internally by the library. It should not be called by user code.
class Connection # :nodoc:
LdapVersion = 3
#--
# initialize
#
def initialize server
begin
@conn = TCPsocket.new( server[:host], server[:port] )
rescue
raise LdapError.new( "no connection to server" )
end
if server[:encryption]
setup_encryption server[:encryption]
end
yield self if block_given?
end
#--
# Helper method called only from new, and only after we have a successfully-opened
# @conn instance variable, which is a TCP connection.
# Depending on the received arguments, we establish SSL, potentially replacing
# the value of @conn accordingly.
# Don't generate any errors here if no encryption is requested.
# DO raise LdapError objects if encryption is requested and we have trouble setting
# it up. That includes if OpenSSL is not set up on the machine. (Question:
# how does the Ruby OpenSSL wrapper react in that case?)
# DO NOT filter exceptions raised by the OpenSSL library. Let them pass back
# to the user. That should make it easier for us to debug the problem reports.
# Presumably (hopefully?) that will also produce recognizable errors if someone
# tries to use this on a machine without OpenSSL.
#
# The simple_tls method is intended as the simplest, stupidest, easiest solution
# for people who want nothing more than encrypted comms with the LDAP server.
# It doesn't do any server-cert validation and requires nothing in the way
# of key files and root-cert files, etc etc.
# OBSERVE: WE REPLACE the value of @conn, which is presumed to be a connected
# TCPsocket object.
#
def setup_encryption args
case args[:method]
when :simple_tls
raise LdapError.new("openssl unavailable") unless $net_ldap_openssl_available
ctx = OpenSSL::SSL::SSLContext.new
@conn = OpenSSL::SSL::SSLSocket.new(@conn, ctx)
@conn.connect
@conn.sync_close = true
# additional branches requiring server validation and peer certs, etc. go here.
else
raise LdapError.new( "unsupported encryption method #{args[:method]}" )
end
end
#--
# close
# This is provided as a convenience method to make
# sure a connection object gets closed without waiting
# for a GC to happen. Clients shouldn't have to call it,
# but perhaps it will come in handy someday.
def close
@conn.close
@conn = nil
end
#--
# next_msgid
#
def next_msgid
@msgid ||= 0
@msgid += 1
end
#--
# bind
#
def bind auth
user,psw = case auth[:method]
when :anonymous
["",""]
when :simple
[auth[:username] || auth[:dn], auth[:password]]
end
raise LdapError.new( "invalid binding information" ) unless (user && psw)
msgid = next_msgid.to_ber
request = [LdapVersion.to_ber, user.to_ber, psw.to_ber_contextspecific(0)].to_ber_appsequence(0)
request_pkt = [msgid, request].to_ber_sequence
@conn.write request_pkt
(be = @conn.read_ber(AsnSyntax) and pdu = Net::LdapPdu.new( be )) or raise LdapError.new( "no bind result" )
pdu.result_code
end
#--
# search
# Alternate implementation, this yields each search entry to the caller
# as it are received.
# TODO, certain search parameters are hardcoded.
# TODO, if we mis-parse the server results or the results are wrong, we can block
# forever. That's because we keep reading results until we get a type-5 packet,
# which might never come. We need to support the time-limit in the protocol.
#--
# WARNING: this code substantially recapitulates the searchx method.
#
# 02May06: Well, I added support for RFC-2696-style paged searches.
# This is used on all queries because the extension is marked non-critical.
# As far as I know, only A/D uses this, but it's required for A/D. Otherwise
# you won't get more than 1000 results back from a query.
# This implementation is kindof clunky and should probably be refactored.
# Also, is it my imagination, or are A/Ds the slowest directory servers ever???
# OpenLDAP newer than version 2.2.0 supports paged searches.
#
def search args = {}
search_filter = (args && args[:filter]) || Filter.eq( "objectclass", "*" )
search_filter = Filter.construct(search_filter) if search_filter.is_a?(String)
search_base = (args && args[:base]) || "dc=example,dc=com"
search_attributes = ((args && args[:attributes]) || []).map {|attr| attr.to_s.to_ber}
return_referrals = args && args[:return_referrals] == true
attributes_only = (args and args[:attributes_only] == true)
scope = args[:scope] || Net::LDAP::SearchScope_WholeSubtree
raise LdapError.new( "invalid search scope" ) unless SearchScopes.include?(scope)
# An interesting value for the size limit would be close to A/D's built-in
# page limit of 1000 records, but openLDAP newer than version 2.2.0 chokes
# on anything bigger than 126. You get a silent error that is easily visible
# by running slapd in debug mode. Go figure.
rfc2696_cookie = [126, ""]
result_code = 0
loop {
# should collect this into a private helper to clarify the structure
request = [
search_base.to_ber,
scope.to_ber_enumerated,
0.to_ber_enumerated,
0.to_ber,
0.to_ber,
attributes_only.to_ber,
search_filter.to_ber,
search_attributes.to_ber_sequence
].to_ber_appsequence(3)
controls = [
[
LdapControls::PagedResults.to_ber,
false.to_ber, # criticality MUST be false to interoperate with normal LDAPs.
rfc2696_cookie.map{|v| v.to_ber}.to_ber_sequence.to_s.to_ber
].to_ber_sequence
].to_ber_contextspecific(0)
pkt = [next_msgid.to_ber, request, controls].to_ber_sequence
@conn.write pkt
result_code = 0
controls = []
while (be = @conn.read_ber(AsnSyntax)) && (pdu = LdapPdu.new( be ))
case pdu.app_tag
when 4 # search-data
yield( pdu.search_entry ) if block_given?
when 19 # search-referral
if return_referrals
if block_given?
se = Net::LDAP::Entry.new
se[:search_referrals] = (pdu.search_referrals || [])
yield se
end
end
#p pdu.referrals
when 5 # search-result
result_code = pdu.result_code
controls = pdu.result_controls
break
else
raise LdapError.new( "invalid response-type in search: #{pdu.app_tag}" )
end
end
# When we get here, we have seen a type-5 response.
# If there is no error AND there is an RFC-2696 cookie,
# then query again for the next page of results.
# If not, we're done.
# Don't screw this up or we'll break every search we do.
#
# Noticed 02Sep06, look at the read_ber call in this loop,
# shouldn't that have a parameter of AsnSyntax? Does this
# just accidentally work? According to RFC-2696, the value
# expected in this position is of type OCTET STRING, covered
# in the default syntax supported by read_ber, so I guess
# we're ok.
#
more_pages = false
if result_code == 0 and controls
controls.each do |c|
if c.oid == LdapControls::PagedResults
more_pages = false # just in case some bogus server sends us >1 of these.
if c.value and c.value.length > 0
cookie = c.value.read_ber[1]
if cookie and cookie.length > 0
rfc2696_cookie[1] = cookie
more_pages = true
end
end
end
end
end
break unless more_pages
} # loop
result_code
end
#--
# modify
# TODO, need to support a time limit, in case the server fails to respond.
# TODO!!! We're throwing an exception here on empty DN.
# Should return a proper error instead, probaby from farther up the chain.
# TODO!!! If the user specifies a bogus opcode, we'll throw a
# confusing error here ("to_ber_enumerated is not defined on nil").
#
def modify args
modify_dn = args[:dn] or raise "Unable to modify empty DN"
modify_ops = []
a = args[:operations] and a.each {|op, attr, values|
# TODO, fix the following line, which gives a bogus error
# if the opcode is invalid.
op_1 = {:add => 0, :delete => 1, :replace => 2} [op.to_sym].to_ber_enumerated
modify_ops << [op_1, [attr.to_s.to_ber, values.to_a.map {|v| v.to_ber}.to_ber_set].to_ber_sequence].to_ber_sequence
}
request = [modify_dn.to_ber, modify_ops.to_ber_sequence].to_ber_appsequence(6)
pkt = [next_msgid.to_ber, request].to_ber_sequence
@conn.write pkt
(be = @conn.read_ber(AsnSyntax)) && (pdu = LdapPdu.new( be )) && (pdu.app_tag == 7) or raise LdapError.new( "response missing or invalid" )
pdu.result_code
end
#--
# add
# TODO, need to support a time limit, in case the server fails to respond.
#
def add args
add_dn = args[:dn] or raise LdapError.new("Unable to add empty DN")
add_attrs = []
a = args[:attributes] and a.each {|k,v|
add_attrs << [ k.to_s.to_ber, v.to_a.map {|m| m.to_ber}.to_ber_set ].to_ber_sequence
}
request = [add_dn.to_ber, add_attrs.to_ber_sequence].to_ber_appsequence(8)
pkt = [next_msgid.to_ber, request].to_ber_sequence
@conn.write pkt
(be = @conn.read_ber(AsnSyntax)) && (pdu = LdapPdu.new( be )) && (pdu.app_tag == 9) or raise LdapError.new( "response missing or invalid" )
pdu.result_code
end
#--
# rename
# TODO, need to support a time limit, in case the server fails to respond.
#
def rename args
old_dn = args[:olddn] or raise "Unable to rename empty DN"
new_rdn = args[:newrdn] or raise "Unable to rename to empty RDN"
delete_attrs = args[:delete_attributes] ? true : false
request = [old_dn.to_ber, new_rdn.to_ber, delete_attrs.to_ber].to_ber_appsequence(12)
pkt = [next_msgid.to_ber, request].to_ber_sequence
@conn.write pkt
(be = @conn.read_ber(AsnSyntax)) && (pdu = LdapPdu.new( be )) && (pdu.app_tag == 13) or raise LdapError.new( "response missing or invalid" )
pdu.result_code
end
#--
# delete
# TODO, need to support a time limit, in case the server fails to respond.
#
def delete args
dn = args[:dn] or raise "Unable to delete empty DN"
request = dn.to_s.to_ber_application_string(10)
pkt = [next_msgid.to_ber, request].to_ber_sequence
@conn.write pkt
(be = @conn.read_ber(AsnSyntax)) && (pdu = LdapPdu.new( be )) && (pdu.app_tag == 11) or raise LdapError.new( "response missing or invalid" )
pdu.result_code
end
end # class Connection
end # class LDAP
end # module Net
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