class Net::IMAP::DigestMD5Authenticator

# File lib/net/imap.rb, line 3525
def initialize(user, password, authname = nil)
 @user, @password, @authname = user, password, authname
 @nc, @stage = {}, STAGE_ONE
end

# File lib/net/imap.rb, line 3460
def process(challenge)
 case @stage
 when STAGE_ONE
 @stage = STAGE_TWO
 sparams = {}
 c = StringScanner.new(challenge)
 while c.scan(/(?:\s*,)?\s*(\w+)=("(?:[^\"]+|\.)*"|[^,]+)\s*/)
 k, v = c[1], c[2]
 if v =~ /^"(.*)"$/
 v = 1ドル
 if v =~ /,/
 v = v.split(',')
 end
 end
 sparams[k] = v
 end
 raise DataFormatError, "Bad Challenge: '#{challenge}'" unless c.rest.size == 0
 raise Error, "Server does not support auth (qop = #{sparams['qop'].join(',')})" unless sparams['qop'].include?("auth")
 response = {
 :nonce => sparams['nonce'],
 :username => @user,
 :realm => sparams['realm'],
 :cnonce => Digest::MD5.hexdigest("%.15f:%.15f:%d" % [Time.now.to_f, rand, Process.pid.to_s]),
 :'digest-uri' => 'imap/' + sparams['realm'],
 :qop => 'auth',
 :maxbuf => 65535,
 :nc => "%08d" % nc(sparams['nonce']),
 :charset => sparams['charset'],
 }
 response[:authzid] = @authname unless @authname.nil?
 # now, the real thing
 a0 = Digest::MD5.digest( [ response.values_at(:username, :realm), @password ].join(':') )
 a1 = [ a0, response.values_at(:nonce,:cnonce) ].join(':')
 a1 << ':' + response[:authzid] unless response[:authzid].nil?
 a2 = "AUTHENTICATE:" + response[:'digest-uri']
 a2 << ":00000000000000000000000000000000" if response[:qop] and response[:qop] =~ /^auth-(?:conf|int)$/
 response[:response] = Digest::MD5.hexdigest(
 [
 Digest::MD5.hexdigest(a1),
 response.values_at(:nonce, :nc, :cnonce, :qop),
 Digest::MD5.hexdigest(a2)
 ].join(':')
 )
 return response.keys.map {|key| qdval(key.to_s, response[key]) }.join(',')
 when STAGE_TWO
 @stage = nil
 # if at the second stage, return an empty string
 if challenge =~ /rspauth=/
 return ''
 else
 raise ResponseParseError, challenge
 end
 else
 raise ResponseParseError, challenge
 end
end

# File lib/net/imap.rb, line 3535
def nc(nonce)
 if @nc.has_key? nonce
 @nc[nonce] = @nc[nonce] + 1
 else
 @nc[nonce] = 1
 end
 return @nc[nonce]
end

# File lib/net/imap.rb, line 3545
def qdval(k, v)
 return if k.nil? or v.nil?
 if %w"username authzid realm nonce cnonce digest-uri qop".include? k
 v.gsub!(/([\"])/, "\\1円")
 return '%s="%s"' % [k, v]
 else
 return '%s=%s' % [k, v]
 end
end