Class BCrypt::Engine
In: lib/bcrypt.rb
Parent: Object

A Ruby wrapper for the bcrypt() C extension calls and the Java calls.

Methods

Constants

DEFAULT_COST = 10   The default computational expense parameter.
MIN_COST = 4   The minimum cost supported by the algorithm.
MAX_SALT_LENGTH = 16   Maximum possible size of bcrypt() salts.

Public Class methods

Autodetects the cost from the salt string.

[Source]

     # File lib/bcrypt.rb, line 109
109:     def self.autodetect_cost(salt)
110:       salt[4..5].to_i
111:     end

Returns the cost factor which will result in computation times less than upper_time_limit_in_ms.

Example:

  BCrypt.calibrate(200)  #=> 10
  BCrypt.calibrate(1000) #=> 12

  # should take less than 200ms
  BCrypt::Password.create("woo", :cost => 10)

  # should take less than 1000ms
  BCrypt::Password.create("woo", :cost => 12)

[Source]

     # File lib/bcrypt.rb, line 99
 99:     def self.calibrate(upper_time_limit_in_ms)
100:       40.times do |i|
101:         start_time = Time.now
102:         Password.create("testing testing", :cost => i+1)
103:         end_time = Time.now - start_time
104:         return i if end_time * 1_000 > upper_time_limit_in_ms
105:       end
106:     end

Generates a random salt with a given computational cost.

[Source]

    # File lib/bcrypt.rb, line 61
61:     def self.generate_salt(cost = DEFAULT_COST)
62:       cost = cost.to_i
63:       if cost > 0
64:         if cost < MIN_COST
65:           cost = MIN_COST
66:         end
67:         if RUBY_PLATFORM == "java"
68:           Java.bcrypt_jruby.BCrypt.gensalt(cost)
69:         else
70:           __bc_salt(cost, OpenSSL::Random.random_bytes(MAX_SALT_LENGTH))
71:         end
72:       else
73:         raise Errors::InvalidCost.new("cost must be numeric and > 0")
74:       end
75:     end

Given a secret and a valid salt (see BCrypt::Engine.generate_salt) calculates a bcrypt() password hash.

[Source]

    # File lib/bcrypt.rb, line 40
40:     def self.hash_secret(secret, salt, cost = nil)
41:       if valid_secret?(secret)
42:         if valid_salt?(salt)
43:           if cost.nil?
44:             cost = autodetect_cost(salt)
45:           end
46:           
47:           if RUBY_PLATFORM == "java"
48:             Java.bcrypt_jruby.BCrypt.hashpw(secret.to_s, salt.to_s)
49:           else
50:             __bc_crypt(secret.to_s, salt, cost)
51:           end
52:         else
53:           raise Errors::InvalidSalt.new("invalid salt")
54:         end
55:       else
56:         raise Errors::InvalidSecret.new("invalid secret")
57:       end
58:     end

Returns true if salt is a valid bcrypt() salt, false if not.

[Source]

    # File lib/bcrypt.rb, line 78
78:     def self.valid_salt?(salt)
79:       salt =~ /^\$[0-9a-z]{2,}\$[0-9]{2,}\$[A-Za-z0-9\.\/]{22,}$/
80:     end

Returns true if secret is a valid bcrypt() secret, false if not.

[Source]

    # File lib/bcrypt.rb, line 83
83:     def self.valid_secret?(secret)
84:       secret.respond_to?(:to_s)
85:     end

[Validate]