JezK
Edit File: digest_md5.rb
# frozen_string_literal: true require "digest/md5" require "strscan" # Net::IMAP authenticator for the "`DIGEST-MD5`" SASL mechanism type, specified # in RFC2831(https://tools.ietf.org/html/rfc2831). See Net::IMAP#authenticate. # # == Deprecated # # "+DIGEST-MD5+" has been deprecated by # {RFC6331}[https://tools.ietf.org/html/rfc6331] and should not be relied on for # security. It is included for compatibility with existing servers. class Net::IMAP::DigestMD5Authenticator 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 = $1 if v =~ /,/ v = v.split(',') end end sparams[k] = v end raise DataFormatError, "Bad Challenge: '#{challenge}'" unless c.rest.size == 0 raise Error, "Server does not support auth (qop = #{sparams['qop'].join(',')})" unless sparams['qop'].include?("auth") response = { :nonce => sparams['nonce'], :username => @user, :realm => sparams['realm'], :cnonce => Digest::MD5.hexdigest("%.15f:%.15f:%d" % [Time.now.to_f, rand, Process.pid.to_s]), :'digest-uri' => 'imap/' + sparams['realm'], :qop => 'auth', :maxbuf => 65535, :nc => "%08d" % nc(sparams['nonce']), :charset => sparams['charset'], } response[:authzid] = @authname unless @authname.nil? # now, the real thing a0 = Digest::MD5.digest( [ response.values_at(:username, :realm), @password ].join(':') ) a1 = [ a0, response.values_at(:nonce,:cnonce) ].join(':') a1 << ':' + response[:authzid] unless response[:authzid].nil? a2 = "AUTHENTICATE:" + response[:'digest-uri'] a2 << ":00000000000000000000000000000000" if response[:qop] and response[:qop] =~ /^auth-(?:conf|int)$/ 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 def initialize(user, password, authname = nil) @user, @password, @authname = user, password, authname @nc, @stage = {}, STAGE_ONE end private STAGE_ONE = :stage_one STAGE_TWO = :stage_two def nc(nonce) if @nc.has_key? nonce @nc[nonce] = @nc[nonce] + 1 else @nc[nonce] = 1 end return @nc[nonce] end # some responses need quoting 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") return '%s="%s"' % [k, v] else return '%s=%s' % [k, v] end end Net::IMAP.add_authenticator "DIGEST-MD5", self end