module SecureRandom
Secure random number generator interface.
This library is an interface to secure random number generators which are suitable for generating session keys in HTTP cookies, etc.
You can use this library in your application by requiring it:
require 'securerandom'
It supports the following secure random number generators:
-
openssl
-
/dev/urandom
-
Win32
SecureRandom
is extended by the Random::Formatter
module which defines the following methods:
-
alphanumeric
-
base64
-
choose
-
hex
-
rand
-
random_bytes
-
random_number
-
urlsafe_base64
-
uuid
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"
Public Class Methods
# File lib/securerandom.rb, line 69 def bytes(n) return gen_random(n) end
Private Class Methods
# File lib/securerandom.rb, line 75 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
# File lib/securerandom.rb, line 90 def gen_random_urandom(n) ret = Random.urandom(n) unless ret raise NotImplementedError, "No random device" end unless ret.length == n raise NotImplementedError, "Unexpected partial read from random device: only #{ret.length} for #{n} bytes" end ret end
Ruby Core © 1993–2020 Yukihiro Matsumoto
Licensed under the Ruby License.
Ruby Standard Library © contributors
Licensed under their own licenses.