150 lines
4.8 KiB
Ruby
150 lines
4.8 KiB
Ruby
# -*- coding: binary -*-
|
|
|
|
module Rex
|
|
module Proto
|
|
module Kerberos
|
|
module Model
|
|
# This class provides a representation of a Kerberos AP-REP (response) data
|
|
# definition
|
|
class ApRep < Element
|
|
# @!attribute pvno
|
|
# @return [Integer] The protocol version number
|
|
attr_accessor :pvno
|
|
# @!attribute msg_type
|
|
# @return [Integer] The type of a protocol message
|
|
attr_accessor :msg_type
|
|
# @!attribute enc_part
|
|
# @return [Rex::Proto::Kerberos::Model::EncryptedData] The encrypted part of the response
|
|
attr_accessor :enc_part
|
|
|
|
# Decodes the Rex::Proto::Kerberos::Model::ApRep from an input
|
|
#
|
|
# @param input [String, OpenSSL::ASN1::ASN1Data] the input to decode from
|
|
# @return [self] if decoding succeeds
|
|
# @raise [Rex::Proto::Kerberos::Model::Error::KerberosDecodingError] if decoding doesn't succeed
|
|
def decode(input)
|
|
case input
|
|
when String
|
|
decode_string(input)
|
|
when OpenSSL::ASN1::ASN1Data
|
|
decode_asn1(input)
|
|
else
|
|
raise ::Rex::Proto::Kerberos::Model::Error::KerberosDecodingError, 'Failed to decode ApRep, invalid input'
|
|
end
|
|
|
|
self
|
|
end
|
|
|
|
# Encodes the Rex::Proto::Kerberos::Model::ApReq into an ASN.1 String
|
|
#
|
|
# @return [String]
|
|
def encode
|
|
to_asn1.to_der
|
|
end
|
|
|
|
# @return [OpenSSL::ASN1::ASN1Data] The ap_req ASN1Data
|
|
def to_asn1
|
|
elems = []
|
|
|
|
elems << OpenSSL::ASN1::ASN1Data.new([encode_pvno], 0, :CONTEXT_SPECIFIC)
|
|
elems << OpenSSL::ASN1::ASN1Data.new([encode_msg_type], 1, :CONTEXT_SPECIFIC)
|
|
elems << OpenSSL::ASN1::ASN1Data.new([encode_enc_part], 2, :CONTEXT_SPECIFIC)
|
|
|
|
seq = OpenSSL::ASN1::Sequence.new(elems)
|
|
|
|
seq_asn1 = OpenSSL::ASN1::ASN1Data.new([seq], AP_REP, :APPLICATION)
|
|
seq_asn1
|
|
end
|
|
|
|
def decrypt_enc_part(key)
|
|
data = enc_part.decrypt_asn1(key, Rex::Proto::Kerberos::Crypto::KeyUsage::AP_REP_ENCPART)
|
|
|
|
result = Rex::Proto::Kerberos::Model::EncApRepPart::decode(data)
|
|
end
|
|
|
|
private
|
|
|
|
# Encodes the pvno field
|
|
#
|
|
# @return [OpenSSL::ASN1::Integer]
|
|
def encode_pvno
|
|
bn = OpenSSL::BN.new(pvno.to_s)
|
|
int = OpenSSL::ASN1::Integer.new(bn)
|
|
|
|
int
|
|
end
|
|
|
|
# Encodes the msg_type field
|
|
#
|
|
# @return [OpenSSL::ASN1::Integer]
|
|
def encode_msg_type
|
|
bn = OpenSSL::BN.new(msg_type.to_s)
|
|
int = OpenSSL::ASN1::Integer.new(bn)
|
|
|
|
int
|
|
end
|
|
|
|
# Encodes the enc_part field
|
|
#
|
|
# @return [String]
|
|
def encode_enc_part
|
|
enc_part.encode
|
|
end
|
|
|
|
# Decodes a Rex::Proto::Kerberos::Model::ApRep from an String
|
|
#
|
|
# @param input [String] the input to decode from
|
|
def decode_string(input)
|
|
asn1 = OpenSSL::ASN1.decode(input)
|
|
|
|
decode_asn1(asn1)
|
|
end
|
|
|
|
# Decodes a Rex::Proto::Kerberos::Model::ApRep
|
|
#
|
|
# @param input [OpenSSL::ASN1::ASN1Data] the input to decode from
|
|
# @raise [Rex::Proto::Kerberos::Model::Error::KerberosDecodingError] if decoding doesn't succeed
|
|
def decode_asn1(input)
|
|
input.value[0].value.each do |val|
|
|
case val.tag
|
|
when 0
|
|
self.pvno = decode_pvno(val)
|
|
when 1
|
|
self.msg_type = decode_msg_type(val)
|
|
when 2
|
|
self.enc_part = decode_enc_part(val)
|
|
else
|
|
raise ::Rex::Proto::Kerberos::Model::Error::KerberosDecodingError, "Failed to decode AP-REP SEQUENCE (#{val.tag})"
|
|
end
|
|
end
|
|
end
|
|
|
|
# Decodes the pvno from an OpenSSL::ASN1::ASN1Data
|
|
#
|
|
# @param input [OpenSSL::ASN1::ASN1Data] the input to decode from
|
|
# @return [Integer]
|
|
def decode_pvno(input)
|
|
input.value[0].value.to_i
|
|
end
|
|
|
|
# Decodes the msg_type from an OpenSSL::ASN1::ASN1Data
|
|
#
|
|
# @param input [OpenSSL::ASN1::ASN1Data] the input to decode from
|
|
# @return [Integer]
|
|
def decode_msg_type(input)
|
|
input.value[0].value.to_i
|
|
end
|
|
|
|
# Decodes the enc_part
|
|
#
|
|
# @param input [OpenSSL::ASN1::ASN1Data] the input to decode from
|
|
# @return [Rex::Proto::Kerberos::Model::EncryptedData]
|
|
def decode_enc_part(input)
|
|
Rex::Proto::Kerberos::Model::EncryptedData.decode(input.value[0])
|
|
end
|
|
end
|
|
end
|
|
end
|
|
end
|
|
end
|