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Merge branch 'ldap-pdu-cleanup', remote branch 'halostatue/ldap-pdu-cleanup' into ldap-pdu-cleanup

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Rory O'Connell 2010-04-15 17:05:40 -05:00
parent e981a11208 6eaf87dc56
commit 0fce1048a5
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479
lib/net/ldap/pdu.rb
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@ -1,4 +1,3 @@
#
# LDAP PDU support classes # LDAP PDU support classes
# #
#---------------------------------------------------------------------------- #----------------------------------------------------------------------------
@ -25,233 +24,255 @@
require 'ostruct' require 'ostruct'
##
# Defines the Protocol Data Unit (PDU) for LDAP. An LDAP PDU always looks
# like a BER SEQUENCE with at least two elements: an INTEGER message ID
# number and an application-specific SEQUENCE. Some LDAPv3 packets also
# include an optional third element, a sequence of "controls" (see RFC 2251
# section 4.1.12 for more information).
#
# The application-specific tag in the sequence tells us what kind of packet
# it is, and each kind has its own format, defined in RFC-1777.
#
# Observe that many clients (such as ldapsearch) do not necessarily enforce
# the expected application tags on received protocol packets. This
# implementation does interpret the RFC strictly in this regard, and it
# remains to be seen whether there are servers out there that will not work
# well with our approach.
#
# Currently, we only support controls on SearchResult.
class Net::LDAP::PDU
class Error < RuntimeError; end
##
# This message packet is a bind request.
BindRequest = 0
BindResult = 1
UnbindRequest = 2
SearchRequest = 3
SearchReturnedData = 4
SearchResult = 5
ModifyResponse = 7
AddResponse = 9
DeleteResponse = 11
ModifyRDNResponse = 13
SearchResultReferral = 19
ExtendedRequest = 23
ExtendedResponse = 24
##
# The LDAP packet message ID.
attr_reader :message_id
alias_method :msg_id, :message_id
##
# The application protocol format tag.
attr_reader :app_tag
attr_reader :search_entry
attr_reader :search_referrals
attr_reader :search_parameters
attr_reader :bind_parameters
##
# Returns RFC-2251 Controls if any.
attr_reader :ldap_controls
alias_method :result_controls, :ldap_controls
# Messy. Does this functionality belong somewhere else?
def initialize(ber_object)
begin
@message_id = ber_object[0].to_i
# Grab the bottom five bits of the identifier so we know which type of
# PDU this is.
#
# This is safe enough in LDAP-land, but it is recommended that other
# approaches be taken for other protocols in the case that there's an
# app-specific tag that has both primitive and constructed forms.
@app_tag = ber_object[1].ber_identifier & 0x1f
@ldap_controls = []
rescue Exception => ex
raise Net::LDAP::PDU::Error, "LDAP PDU Format Error: #{ex.message}"
end
case @app_tag
when BindResult
parse_bind_response(ber_object[1])
when SearchReturnedData
parse_search_return(ber_object[1])
when SearchResultReferral
parse_search_referral(ber_object[1])
when SearchResult
parse_ldap_result(ber_object[1])
when ModifyResponse
parse_ldap_result(ber_object[1])
when AddResponse
parse_ldap_result(ber_object[1])
when DeleteResponse
parse_ldap_result(ber_object[1])
when ModifyRDNResponse
parse_ldap_result(ber_object[1])
when SearchRequest
parse_ldap_search_request(ber_object[1])
when BindRequest
parse_bind_request(ber_object[1])
when UnbindRequest
parse_unbind_request(ber_object[1])
when ExtendedResponse
parse_ldap_result(ber_object[1])
else
raise LdapPduError.new("unknown pdu-type: #{@app_tag}")
end
parse_controls(ber_object[2]) if ber_object[2]
end
##
# Returns a hash which (usually) defines the members :resultCode,
# :errorMessage, and :matchedDN. These values come directly from an LDAP
# response packet returned by the remote peer. Also see #result_code.
def result
@ldap_result || {}
end
##
# This returns an LDAP result code taken from the PDU, but it will be nil
# if there wasn't a result code. That can easily happen depending on the
# type of packet.
def result_code(code = :resultCode)
@ldap_result and @ldap_result[code]
end
##
# Return serverSaslCreds, which are only present in BindResponse packets.
#--
# Messy. Does this functionality belong somewhere else? We ought to
# refactor the accessors of this class before they get any kludgier.
def result_server_sasl_creds
@ldap_result && @ldap_result[:serverSaslCreds]
end
def parse_ldap_result(sequence)
sequence.length >= 3 or raise Net::LDAP::PDU::Error, "Invalid LDAP result length."
@ldap_result = {
:resultCode => sequence[0],
:matchedDN => sequence[1],
:errorMessage => sequence[2]
}
end
private :parse_ldap_result
##
# A Bind Response may have an additional field, ID [7], serverSaslCreds,
# per RFC 2251 pgh 4.2.3.
def parse_bind_response(sequence)
sequence.length >= 3 or raise Net::LDAP::PDU::Error, "Invalid LDAP Bind Response length."
parse_ldap_result(sequence)
@ldap_result[:serverSaslCreds] = sequence[3] if sequence.length >= 4
@ldap_result
end
private :parse_bind_response
# Definition from RFC 1777 (we're handling application-4 here).
#
# Search Response ::=
# CHOICE {
# entry [APPLICATION 4] SEQUENCE {
# objectName LDAPDN,
# attributes SEQUENCE OF SEQUENCE {
# AttributeType,
# SET OF AttributeValue
# }
# },
# resultCode [APPLICATION 5] LDAPResult
# }
#
# We concoct a search response that is a hash of the returned attribute
# values.
#
# NOW OBSERVE CAREFULLY: WE ARE DOWNCASING THE RETURNED ATTRIBUTE NAMES.
#
# This is to make them more predictable for user programs, but it may not
# be a good idea. Maybe this should be configurable.
def parse_search_return(sequence)
sequence.length >= 2 or raise Net::LDAP::PDU::Error, "Invalid Search Response length."
@search_entry = LDAP::Entry.new(sequence[0])
sequence[1].each { |seq| @search_entry[seq[0]] = seq[1] }
end
private :parse_search_return
##
# A search referral is a sequence of one or more LDAP URIs. Any number of
# search-referral replies can be returned by the server, interspersed with
# normal replies in any order.
#--
# Until I can think of a better way to do this, we'll return the referrals
# as an array. It'll be up to higher-level handlers to expose something
# reasonable to the client.
def parse_search_referral(uris)
@search_referrals = uris
end
private :parse_search_referral
##
# Per RFC 2251, an LDAP "control" is a sequence of tuples, each consisting
# of an OID, a boolean criticality flag defaulting FALSE, and an OPTIONAL
# Octet String. If only two fields are given, the second one may be either
# criticality or data, since criticality has a default value. Someday we
# may want to come back here and add support for some of more-widely used
# controls. RFC-2696 is a good example.
def parse_controls(sequence)
@ldap_controls = sequence.map do |control|
o = OpenStruct.new
o.oid, o.criticality, o.value = control[0], control[1], control[2]
if o.criticality and o.criticality.is_a?(String)
o.value = o.criticality
o.criticality = false
end
o
end
end
private :parse_controls
# (provisional, must document)
def parse_ldap_search_request(sequence)
s = OpenStruct.new
s.base_object, s.scope, s.deref_aliases, s.size_limit, s.time_limit,
s.types_only, s.filter, s.attributes = sequence
@search_parameters = s
end
private :parse_ldap_search_request
# (provisional, must document)
def parse_bind_request sequence
s = OpenStruct.new
s.version, s.name, s.authentication = sequence
@bind_parameters = s
end
private :parse_bind_request
# (provisional, must document)
# UnbindRequest has no content so this is a no-op.
def parse_unbind_request(sequence)
nil
end
private :parse_unbind_request
end
module Net module Net
class LdapPduError < StandardError; end ##
# Handle the renamed constants.
class LdapPdu def self.const_missing(name) #:nodoc:
BindRequest = 0 case name.to_s
BindResult = 1 when "LdapPdu"
UnbindRequest = 2 warn "Net::#{name} has been deprecated. Use Net::LDAP::PDU instead."
SearchRequest = 3 Net::LDAP::PDU
SearchReturnedData = 4 when "LdapPduError"
SearchResult = 5 warn "Net::#{name} has been deprecated. Use Net::LDAP::PDU::Error instead."
ModifyResponse = 7 Net::LDAP::PDU::Error
AddResponse = 9 else
DeleteResponse = 11 super
ModifyRDNResponse = 13 end
SearchResultReferral = 19 end
ExtendedRequest = 23
ExtendedResponse = 24
attr_reader :msg_id, :app_tag
attr_reader :search_dn, :search_attributes, :search_entry
attr_reader :search_referrals
attr_reader :search_parameters, :bind_parameters
# An LDAP PDU always looks like a BerSequence with
# at least two elements: an integer (message-id number), and
# an application-specific sequence.
# Some LDAPv3 packets also include an optional
# third element, which is a sequence of "controls"
# (See RFC 2251, section 4.1.12).
# The application-specific tag in the sequence tells
# us what kind of packet it is, and each kind has its
# own format, defined in RFC-1777.
# Observe that many clients (such as ldapsearch)
# do not necessarily enforce the expected application
# tags on received protocol packets. This implementation
# does interpret the RFC strictly in this regard, and
# it remains to be seen whether there are servers out
# there that will not work well with our approach.
#
# Added a controls-processor to SearchResult.
# Didn't add it everywhere because it just _feels_
# like it will need to be refactored.
#
def initialize ber_object
begin
@msg_id = ber_object[0].to_i
# Modified 25Nov06. We want to "un-decorate" the ber-identifier
# of the incoming packet. Originally we did this by subtracting 0x60,
# which ASSUMES the identifier is a constructed app-specific value.
# But at least one value (UnbindRequest) is app-specific primitive.
# So it makes more sense just to grab the bottom five bits.
#@app_tag = ber_object[1].ber_identifier - 0x60
@app_tag = ber_object[1].ber_identifier & 31
@ldap_controls = []
rescue
# any error becomes a data-format error
raise LdapPduError.new( "ldap-pdu format error" )
end
case @app_tag
when BindResult
parse_bind_response ber_object[1]
when SearchReturnedData
parse_search_return ber_object[1]
when SearchResultReferral
parse_search_referral ber_object[1]
when SearchResult
parse_ldap_result ber_object[1]
parse_controls(ber_object[2]) if ber_object[2]
when ModifyResponse
parse_ldap_result ber_object[1]
when AddResponse
parse_ldap_result ber_object[1]
when DeleteResponse
parse_ldap_result ber_object[1]
when ModifyRDNResponse
parse_ldap_result ber_object[1]
when SearchRequest
parse_ldap_search_request ber_object[1]
when BindRequest
parse_bind_request ber_object[1]
when UnbindRequest
parse_unbind_request ber_object[1]
when ExtendedResponse
parse_ldap_result ber_object[1]
else
raise LdapPduError.new( "unknown pdu-type: #{@app_tag}" )
end
end
# Returns a hash which (usually) defines the members :resultCode, :errorMessage, and :matchedDN.
# These values come directly from an LDAP response packet returned by the remote peer.
# See #result_code for a sugaring.
#
def result
@ldap_result || {}
end
# This returns an LDAP result code taken from the PDU,
# but it will be nil if there wasn't a result code.
# That can easily happen depending on the type of packet.
#
def result_code code = :resultCode
@ldap_result and @ldap_result[code]
end
# Return RFC-2251 Controls if any.
# Messy. Does this functionality belong somewhere else?
def result_controls
@ldap_controls
end
# Return serverSaslCreds, which are only present in BindResponse packets.
# Messy. Does this functionality belong somewhere else?
# We ought to refactor the accessors of this class before they get any kludgier.
def result_server_sasl_creds
@ldap_result && @ldap_result[:serverSaslCreds]
end
# parse_ldap_result
#
def parse_ldap_result sequence
sequence.length >= 3 or raise LdapPduError
@ldap_result = {:resultCode => sequence[0], :matchedDN => sequence[1], :errorMessage => sequence[2]}
end
private :parse_ldap_result
# A Bind Response may have an additional field, ID [7], serverSaslCreds, per RFC 2251 pgh 4.2.3.
#
def parse_bind_response sequence
sequence.length >= 3 or raise LdapPduError
@ldap_result = {:resultCode => sequence[0], :matchedDN => sequence[1], :errorMessage => sequence[2]}
@ldap_result[:serverSaslCreds] = sequence[3] if sequence.length >= 4
@ldap_result
end
private :parse_bind_response
# Definition from RFC 1777 (we're handling application-4 here)
#
# Search Response ::=
# CHOICE {
# entry [APPLICATION 4] SEQUENCE {
# objectName LDAPDN,
# attributes SEQUENCE OF SEQUENCE {
# AttributeType,
# SET OF AttributeValue
# }
# },
# resultCode [APPLICATION 5] LDAPResult
# }
#
# We concoct a search response that is a hash of the returned attribute values.
# NOW OBSERVE CAREFULLY: WE ARE DOWNCASING THE RETURNED ATTRIBUTE NAMES.
# This is to make them more predictable for user programs, but it
# may not be a good idea. Maybe this should be configurable.
# ALTERNATE IMPLEMENTATION: In addition to @search_dn and @search_attributes,
# we also return @search_entry, which is an LDAP::Entry object.
# If that works out well, then we'll remove the first two.
#
# Provisionally removed obsolete search_attributes and search_dn, 04May06.
#
def parse_search_return sequence
sequence.length >= 2 or raise LdapPduError
@search_entry = LDAP::Entry.new( sequence[0] )
sequence[1].each {|seq|
@search_entry[seq[0]] = seq[1]
}
end
# A search referral is a sequence of one or more LDAP URIs.
# Any number of search-referral replies can be returned by the server, interspersed
# with normal replies in any order.
# Until I can think of a better way to do this, we'll return the referrals as an array.
# It'll be up to higher-level handlers to expose something reasonable to the client.
def parse_search_referral uris
@search_referrals = uris
end
# Per RFC 2251, an LDAP "control" is a sequence of tuples, each consisting
# of an OID, a boolean criticality flag defaulting FALSE, and an OPTIONAL
# Octet String. If only two fields are given, the second one may be
# either criticality or data, since criticality has a default value.
# Someday we may want to come back here and add support for some of
# more-widely used controls. RFC-2696 is a good example.
#
def parse_controls sequence
@ldap_controls = sequence.map do |control|
o = OpenStruct.new
o.oid,o.criticality,o.value = control[0],control[1],control[2]
if o.criticality and o.criticality.is_a?(String)
o.value = o.criticality
o.criticality = false
end
o
end
end
private :parse_controls
# (provisional, must document)
def parse_ldap_search_request sequence
s = OpenStruct.new
s.base_object,
s.scope,
s.deref_aliases,
s.size_limit,
s.time_limit,
s.types_only,
s.filter,
s.attributes = sequence
@search_parameters = s
end
# (provisional, must document)
def parse_bind_request sequence
s = OpenStruct.new
s.version,
s.name,
s.authentication = sequence
@bind_parameters = s
end
# (provisional, must document)
# UnbindRequest has no content so this is a no-op.
def parse_unbind_request sequence
end
end
end # module Net end # module Net