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require 'rasn1'
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module Rex::Proto::Gss
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  # Initial negotiation token
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  # https://datatracker.ietf.org/doc/html/rfc4178#section-4.2
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  class MechType < RASN1::Types::ObjectId
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  end
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  class MechTypeList < RASN1::Model
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    sequence_of(:mech_type, Rex::Proto::Gss::MechType)
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  end
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  class ContextFlags < RASN1::Types::BitString
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    def initialize(options = {})
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      options[:bit_length] = 32
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      super
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    end
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  end
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  class NegTokenInit < RASN1::Model
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    sequence :neg_token_init, explicit: 0, class: :context, constructed: true,
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             content: [wrapper(model(:mech_type_list, Rex::Proto::Gss::MechTypeList), explicit: 0, constructed: true),
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                       wrapper(model(:context_flags, Rex::Proto::Gss::ContextFlags), explicit: 1, constructed: true, optional: true),
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                       octet_string(:mech_token, explicit: 2, constructed: true, optional: true),
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                       octet_string(:mech_list_mic, explicit: 3, optional: true)
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             ]
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  end
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  class SpnegoNegTokenInit < RASN1::Model
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    sequence :gssapi, implicit: 0, class: :application, constructed: true,
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             content: [objectid(:oid),
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                       model(:neg_token_init, Rex::Proto::Gss::NegTokenInit)]
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    def mech_token
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      self[:gssapi][:neg_token_init][:mech_token].value
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    end
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    def mech_type_list
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      self[:gssapi][:neg_token_init][:mech_type_list][:mech_type]
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    end
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  end
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end
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