class BCrypt::Engine
A Ruby wrapper for the bcrypt() C extension calls and the Java calls.
Constants
- DEFAULT_COST
The default computational expense parameter.
- MAX_SALT_LENGTH
Maximum possible size of bcrypt() salts.
- MIN_COST
The minimum cost supported by the algorithm.
Public Class Methods
Given a secret and a salt, generates a salted hash (which you can then store safely).
static VALUE bc_crypt(VALUE self, VALUE key, VALUE setting) { char * value; void * data; int size; VALUE out; data = NULL; size = 0xDEADBEEF; if(NIL_P(key) || NIL_P(setting)) return Qnil; value = crypt_ra( NIL_P(key) ? NULL : StringValuePtr(key), NIL_P(setting) ? NULL : StringValuePtr(setting), &data, &size); if(!value) return Qnil; out = rb_str_new(data, size - 1); xfree(data); return out; }
Given a logarithmic cost parameter, generates a salt for use with
bc_crypt
.
static VALUE bc_salt(VALUE self, VALUE prefix, VALUE count, VALUE input) { char * salt; VALUE str_salt; salt = crypt_gensalt_ra( StringValuePtr(prefix), NUM2ULONG(count), NIL_P(input) ? NULL : StringValuePtr(input), NIL_P(input) ? 0 : RSTRING_LEN(input)); if(!salt) return Qnil; str_salt = rb_str_new2(salt); xfree(salt); return str_salt; }
Autodetects the cost from the salt string.
# File lib/bcrypt/engine.rb, line 111 def self.autodetect_cost(salt) salt[4..5].to_i end
Returns the cost factor which will result in computation times less than
upper_time_limit_in_ms
.
Example:
BCrypt::Engine.calibrate(200) #=> 10 BCrypt::Engine.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)
# File lib/bcrypt/engine.rb, line 101 def self.calibrate(upper_time_limit_in_ms) 40.times do |i| start_time = Time.now Password.create("testing testing", :cost => i+1) end_time = Time.now - start_time return i if end_time * 1_000 > upper_time_limit_in_ms end end
Returns the cost factor that will be used if one is not specified when creating a password hash. Defaults to DEFAULT_COST if not set.
# File lib/bcrypt/engine.rb, line 22 def self.cost @cost || DEFAULT_COST end
Set a default cost factor that will be used if one is not specified when creating a password hash.
Example:
BCrypt::Engine::DEFAULT_COST #=> 10 BCrypt::Password.create('secret').cost #=> 10 BCrypt::Engine.cost = 8 BCrypt::Password.create('secret').cost #=> 8 # cost can still be overridden as needed BCrypt::Password.create('secret', :cost => 6).cost #=> 6
# File lib/bcrypt/engine.rb, line 39 def self.cost=(cost) @cost = cost end
Generates a random salt with a given computational cost.
# File lib/bcrypt/engine.rb, line 62 def self.generate_salt(cost = self.cost) cost = cost.to_i if cost > 0 if cost < MIN_COST cost = MIN_COST end if RUBY_PLATFORM == "java" Java.bcrypt_jruby.BCrypt.gensalt(cost) else prefix = "$2a$05$CCCCCCCCCCCCCCCCCCCCC.E5YPO9kmyuRGyh0XouQYb4YMJKvyOeW" __bc_salt(prefix, cost, OpenSSL::Random.random_bytes(MAX_SALT_LENGTH)) end else raise Errors::InvalidCost.new("cost must be numeric and > 0") end end
Given a secret and a valid salt (see ::generate_salt) calculates a bcrypt() password hash.
# File lib/bcrypt/engine.rb, line 45 def self.hash_secret(secret, salt, _ = nil) if valid_secret?(secret) if valid_salt?(salt) if RUBY_PLATFORM == "java" Java.bcrypt_jruby.BCrypt.hashpw(secret.to_s, salt.to_s) else __bc_crypt(secret.to_s, salt) end else raise Errors::InvalidSalt.new("invalid salt") end else raise Errors::InvalidSecret.new("invalid secret") end end
Returns true if salt
is a valid bcrypt() salt, false if not.
# File lib/bcrypt/engine.rb, line 80 def self.valid_salt?(salt) !!(salt =~ /^\$[0-9a-z]{2,}\$[0-9]{2,}\$[A-Za-z0-9\.\/]{22,}$/) end
Returns true if secret
is a valid bcrypt() secret, false if
not.
# File lib/bcrypt/engine.rb, line 85 def self.valid_secret?(secret) secret.respond_to?(:to_s) end