diff options
Diffstat (limited to 'lib/securerandom.rb')
| -rw-r--r-- | lib/securerandom.rb | 267 |
1 files changed, 23 insertions, 244 deletions
diff --git a/lib/securerandom.rb b/lib/securerandom.rb index 323d4af3b7..81757f3100 100644 --- a/lib/securerandom.rb +++ b/lib/securerandom.rb @@ -1,6 +1,8 @@ # -*- coding: us-ascii -*- # frozen_string_literal: true +require 'random/formatter' + # == Secure random number generator interface. # # This library is an interface to secure random number generators which are @@ -33,61 +35,32 @@ # These methods are usable as class methods of SecureRandom such as # +SecureRandom.hex+. # -# === Examples -# -# Generate random hexadecimal strings: -# -# require 'securerandom' -# -# SecureRandom.hex(10) #=> "52750b30ffbc7de3b362" -# SecureRandom.hex(10) #=> "92b15d6c8dc4beb5f559" -# SecureRandom.hex(13) #=> "39b290146bea6ce975c37cfc23" -# -# Generate random base64 strings: -# -# SecureRandom.base64(10) #=> "EcmTPZwWRAozdA==" -# SecureRandom.base64(10) #=> "KO1nIU+p9DKxGg==" -# SecureRandom.base64(12) #=> "7kJSM/MzBJI+75j8" -# -# Generate random binary strings: -# -# SecureRandom.random_bytes(10) #=> "\016\t{\370g\310pbr\301" -# SecureRandom.random_bytes(10) #=> "\323U\030TO\234\357\020\a\337" -# -# Generate alphanumeric strings: -# -# SecureRandom.alphanumeric(10) #=> "S8baxMJnPl" -# SecureRandom.alphanumeric(10) #=> "aOxAg8BAJe" -# -# Generate UUIDs: -# -# SecureRandom.uuid #=> "2d931510-d99f-494a-8c67-87feb05e1594" -# SecureRandom.uuid #=> "bad85eb9-0713-4da7-8d36-07a8e4b00eab" -# +# If a secure random number generator is not available, +# +NotImplementedError+ is raised. module SecureRandom + + # The version + VERSION = "0.3.1" + class << self + # Returns a random binary string containing +size+ bytes. + # + # See Random.bytes def bytes(n) return gen_random(n) end private + # :stopdoc: + + # Implementation using OpenSSL def gen_random_openssl(n) - @pid = 0 unless defined?(@pid) - pid = $$ - unless @pid == pid - now = Process.clock_gettime(Process::CLOCK_REALTIME, :nanosecond) - OpenSSL::Random.random_add([now, @pid, pid].join(""), 0.0) - seed = Random.urandom(16) - if (seed) - OpenSSL::Random.random_add(seed, 16) - end - @pid = pid - end return OpenSSL::Random.random_bytes(n) end + # Implementation using system random device def gen_random_urandom(n) ret = Random.urandom(n) unless ret @@ -99,8 +72,11 @@ module SecureRandom ret end - ret = Random.urandom(1) - if ret.nil? + begin + # Check if Random.urandom is available + Random.urandom(1) + alias gen_random gen_random_urandom + rescue RuntimeError begin require 'openssl' rescue NoMethodError @@ -108,209 +84,12 @@ module SecureRandom else alias gen_random gen_random_openssl end - else - alias gen_random gen_random_urandom end - public :gen_random - end -end - -module Random::Formatter - - # SecureRandom.random_bytes generates a random binary string. - # - # The argument _n_ specifies the length of the result string. - # - # If _n_ is not specified or is nil, 16 is assumed. - # It may be larger in future. - # - # The result may contain any byte: "\x00" - "\xff". - # - # require 'securerandom' - # - # SecureRandom.random_bytes #=> "\xD8\\\xE0\xF4\r\xB2\xFC*WM\xFF\x83\x18\xF45\xB6" - # SecureRandom.random_bytes #=> "m\xDC\xFC/\a\x00Uf\xB2\xB2P\xBD\xFF6S\x97" - # - # If a secure random number generator is not available, - # +NotImplementedError+ is raised. - def random_bytes(n=nil) - n = n ? n.to_int : 16 - gen_random(n) - end - - # SecureRandom.hex generates a random hexadecimal string. - # - # The argument _n_ specifies the length, in bytes, of the random number to be generated. - # The length of the resulting hexadecimal string is twice of _n_. - # - # If _n_ is not specified or is nil, 16 is assumed. - # It may be larger in the future. - # - # The result may contain 0-9 and a-f. - # - # require 'securerandom' - # - # SecureRandom.hex #=> "eb693ec8252cd630102fd0d0fb7c3485" - # SecureRandom.hex #=> "91dc3bfb4de5b11d029d376634589b61" - # - # If a secure random number generator is not available, - # +NotImplementedError+ is raised. - def hex(n=nil) - random_bytes(n).unpack("H*")[0] - end - - # SecureRandom.base64 generates a random base64 string. - # - # The argument _n_ specifies the length, in bytes, of the random number - # to be generated. The length of the result string is about 4/3 of _n_. - # - # If _n_ is not specified or is nil, 16 is assumed. - # It may be larger in the future. - # - # The result may contain A-Z, a-z, 0-9, "+", "/" and "=". - # - # require 'securerandom' - # - # SecureRandom.base64 #=> "/2BuBuLf3+WfSKyQbRcc/A==" - # SecureRandom.base64 #=> "6BbW0pxO0YENxn38HMUbcQ==" - # - # If a secure random number generator is not available, - # +NotImplementedError+ is raised. - # - # See RFC 3548 for the definition of base64. - def base64(n=nil) - [random_bytes(n)].pack("m0") - end - - # SecureRandom.urlsafe_base64 generates a random URL-safe base64 string. - # - # The argument _n_ specifies the length, in bytes, of the random number - # to be generated. The length of the result string is about 4/3 of _n_. - # - # If _n_ is not specified or is nil, 16 is assumed. - # It may be larger in the future. - # - # The boolean argument _padding_ specifies the padding. - # If it is false or nil, padding is not generated. - # Otherwise padding is generated. - # By default, padding is not generated because "=" may be used as a URL delimiter. - # - # The result may contain A-Z, a-z, 0-9, "-" and "_". - # "=" is also used if _padding_ is true. - # - # require 'securerandom' - # - # SecureRandom.urlsafe_base64 #=> "b4GOKm4pOYU_-BOXcrUGDg" - # SecureRandom.urlsafe_base64 #=> "UZLdOkzop70Ddx-IJR0ABg" - # - # SecureRandom.urlsafe_base64(nil, true) #=> "i0XQ-7gglIsHGV2_BNPrdQ==" - # SecureRandom.urlsafe_base64(nil, true) #=> "-M8rLhr7JEpJlqFGUMmOxg==" - # - # If a secure random number generator is not available, - # +NotImplementedError+ is raised. - # - # See RFC 3548 for the definition of URL-safe base64. - def urlsafe_base64(n=nil, padding=false) - s = [random_bytes(n)].pack("m0") - s.tr!("+/", "-_") - s.delete!("=") unless padding - s - end - - # SecureRandom.uuid generates a random v4 UUID (Universally Unique IDentifier). - # - # require 'securerandom' - # - # SecureRandom.uuid #=> "2d931510-d99f-494a-8c67-87feb05e1594" - # SecureRandom.uuid #=> "bad85eb9-0713-4da7-8d36-07a8e4b00eab" - # SecureRandom.uuid #=> "62936e70-1815-439b-bf89-8492855a7e6b" - # - # The version 4 UUID is purely random (except the version). - # It doesn't contain meaningful information such as MAC addresses, timestamps, etc. - # - # The result contains 122 random bits (15.25 random bytes). - # - # See RFC 4122 for details of UUID. - # - def uuid - ary = random_bytes(16).unpack("NnnnnN") - ary[2] = (ary[2] & 0x0fff) | 0x4000 - ary[3] = (ary[3] & 0x3fff) | 0x8000 - "%08x-%04x-%04x-%04x-%04x%08x" % ary - end - - private def gen_random(n) - self.bytes(n) - end + # :startdoc: - # SecureRandom.choose generates a string that randomly draws from a - # source array of characters. - # - # The argument _source_ specifies the array of characters from which - # to generate the string. - # The argument _n_ specifies the length, in characters, of the string to be - # generated. - # - # The result may contain whatever characters are in the source array. - # - # require 'securerandom' - # - # SecureRandom.choose([*'l'..'r'], 16) #=> "lmrqpoonmmlqlron" - # SecureRandom.choose([*'0'..'9'], 5) #=> "27309" - # - # If a secure random number generator is not available, - # +NotImplementedError+ is raised. - private def choose(source, n) - size = source.size - m = 1 - limit = size - while limit * size <= 0x100000000 - limit *= size - m += 1 - end - result = ''.dup - while m <= n - rs = random_number(limit) - is = rs.digits(size) - (m-is.length).times { is << 0 } - result << source.values_at(*is).join('') - n -= m - end - if 0 < n - rs = random_number(limit) - is = rs.digits(size) - if is.length < n - (n-is.length).times { is << 0 } - else - is.pop while n < is.length - end - result.concat source.values_at(*is).join('') - end - result - end - - ALPHANUMERIC = [*'A'..'Z', *'a'..'z', *'0'..'9'] - # SecureRandom.alphanumeric generates a random alphanumeric string. - # - # The argument _n_ specifies the length, in characters, of the alphanumeric - # string to be generated. - # - # If _n_ is not specified or is nil, 16 is assumed. - # It may be larger in the future. - # - # The result may contain A-Z, a-z and 0-9. - # - # require 'securerandom' - # - # SecureRandom.alphanumeric #=> "2BuBuLf3WfSKyQbR" - # SecureRandom.alphanumeric(10) #=> "i6K93NdqiH" - # - # If a secure random number generator is not available, - # +NotImplementedError+ is raised. - def alphanumeric(n=nil) - n = 16 if n.nil? - choose(ALPHANUMERIC, n) + # Generate random data bytes for Random::Formatter + public :gen_random end end |