Module: UUID47

Defined in:
lib/uuid47.rb,
lib/uuid47/version.rb

Defined Under Namespace

Classes: Error

Constant Summary collapse

VERSION = 
"0.1.0"

Class Method Summary collapse

Class Method Details

.decode_v4facade(v4facade, key) ⇒ Object 



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# File 'lib/uuid47.rb', line 22

def self.decode_v4facade(v4facade, key)
  uuid_str = UUIDTools::UUID.parse(v4facade).raw
  mask = self.mask48(uuid_str, key)
  # (de)apply mask
  new_uuid_str = self.xor_strings(mask, uuid_str[0..5]) + uuid_str[6..]
  # then set version
  self.set_version(new_uuid_str, 7)
  # then convert to UUID string
  UUIDTools::UUID.parse_raw(new_uuid_str).to_str
end

.encode_v4facade(id_v7, key) ⇒ Object

Your code goes here...



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# File 'lib/uuid47.rb', line 11

def self.encode_v4facade(id_v7, key)
  uuid_str = UUIDTools::UUID.parse(id_v7).raw
  mask = self.mask48(uuid_str, key)
  # apply mask
  new_uuid_str = self.xor_strings(mask, uuid_str[0..5]) + uuid_str[6..]
  # then set version
  self.set_version(new_uuid_str, 4)
  # then convert to UUID string
  UUIDTools::UUID.parse_raw(new_uuid_str).to_str
end

.mask48(raw, key) ⇒ Object 



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# File 'lib/uuid47.rb', line 34

def self.mask48(raw, key)
  msg = ''
  msg += (raw[6].ord & 0x0f).chr
  msg += raw[7]
  msg += (raw[8].ord & 0x3F).chr
  msg += raw[9..15]
  mask_int = SipHash.digest(key, msg)
  mask = ''
  mask += (mask_int >> 40 & 0xff).chr
  mask += (mask_int >> 32 & 0xff).chr
  mask += (mask_int >> 24 & 0xff).chr
  mask += (mask_int >> 16 & 0xff).chr
  mask += (mask_int >> 8  & 0xff).chr
  mask += (mask_int >> 0  & 0xff).chr
  mask
end

.set_version(uuid_str, version) ⇒ Object 



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# File 'lib/uuid47.rb', line 55

def self.set_version(uuid_str, version)
  uuid_str[6] = ((uuid_str[6].ord & 0x0f) | ((version & 0x0f) << 4)).chr
end

.xor_strings(a, b) ⇒ Object 



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# File 'lib/uuid47.rb', line 51

def self.xor_strings(a, b)
  a.bytes.zip(b.bytes).map { |x, y| (x ^ y).chr }.join
end