class Crypto::Bcrypt
Overview
Pure Crystal implementation of the Bcrypt algorithm by Niels Provos and David Mazières, as presented at USENIX in 1999.
The algorithm has a maximum password length limit of 71 characters (see this comment on stackoverflow).
Refer to Crypto::Bcrypt::Password
for a higher level interface.
About the Cost
Bcrypt, like the PBKDF2 or scrypt ciphers, are designed to be slow, so generating rainbow tables or cracking passwords is nearly impossible. Yet, computers are always getting faster and faster, so the actual cost must be incremented every once in a while. Always use the maximum cost that is tolerable, performance wise, for your application. Be sure to test and select this based on your server, not your home computer.
This implementation of Bcrypt is currently 50% slower than pure C solutions, so keep this in mind when selecting your cost. It may be wise to test with Ruby's bcrypt gem which is a binding to OpenBSD's implementation.
Last but not least: beware of denial of services! Always protect your application using an external strategy (eg: rate limiting), otherwise endpoints that verifies bcrypt hashes will be an easy target.
NOTE To use Bcrypt
, you must explicitly import it with require "crypto/bcrypt"
Defined in:
crypto/bcrypt.crConstant Summary
-
COST_RANGE =
4..31
-
DEFAULT_COST =
11
-
PASSWORD_RANGE =
1..72
-
SALT_SIZE =
16
Constructors
-
.new(password : String, salt : String, cost = DEFAULT_COST)
Creates a new
Crypto::Bcrypt
object from the given password with salt and cost. -
.new(password : Bytes, salt : Bytes, cost : Int32 = DEFAULT_COST)
Creates a new
Crypto::Bcrypt
object from the given password with salt in bytes and cost.
Class Method Summary
-
.hash_secret(password, cost = DEFAULT_COST) : String
Hashes the password using bcrypt algorithm using salt obtained via
Random::Secure.random_bytes(SALT_SIZE)
.
Instance Method Summary
- #cost : Int32
- #digest : Bytes
-
#inspect(io : IO) : Nil
Appends a String representation of this object which includes its class name, its object address and the values of all instance variables.
- #password : Bytes
- #salt : Bytes
-
#to_s(io : IO) : Nil
Appends a short String representation of this object which includes its class name and its object address.
-
#to_s : String
Returns a nicely readable and concise string representation of this object, typically intended for users.
- #to_slice(*args, **options)
- #to_slice(*args, **options, &)
Instance methods inherited from class Reference
==(other : self)==(other : JSON::Any)
==(other : YAML::Any)
==(other) ==, dup dup, hash(hasher) hash, initialize initialize, inspect(io : IO) : Nil inspect, object_id : UInt64 object_id, pretty_print(pp) : Nil pretty_print, same?(other : Reference) : Bool
same?(other : Nil) same?, to_s(io : IO) : Nil to_s
Constructor methods inherited from class Reference
new
new,
unsafe_construct(address : Pointer, *args, **opts) : self
unsafe_construct
Class methods inherited from class Reference
pre_initialize(address : Pointer)
pre_initialize
Instance methods inherited from class Object
! : Bool
!,
!=(other)
!=,
!~(other)
!~,
==(other)
==,
===(other : JSON::Any)===(other : YAML::Any)
===(other) ===, =~(other) =~, as(type : Class) as, as?(type : Class) as?, class class, dup dup, hash(hasher)
hash hash, in?(collection : Object) : Bool
in?(*values : Object) : Bool in?, inspect(io : IO) : Nil
inspect : String inspect, is_a?(type : Class) : Bool is_a?, itself itself, nil? : Bool nil?, not_nil!(message)
not_nil! not_nil!, pretty_inspect(width = 79, newline = "\n", indent = 0) : String pretty_inspect, pretty_print(pp : PrettyPrint) : Nil pretty_print, responds_to?(name : Symbol) : Bool responds_to?, tap(&) tap, to_json(io : IO) : Nil
to_json : String to_json, to_pretty_json(indent : String = " ") : String
to_pretty_json(io : IO, indent : String = " ") : Nil to_pretty_json, to_s(io : IO) : Nil
to_s : String to_s, to_yaml(io : IO) : Nil
to_yaml : String to_yaml, try(&) try, unsafe_as(type : T.class) forall T unsafe_as
Class methods inherited from class Object
from_json(string_or_io, root : String)from_json(string_or_io) from_json, from_yaml(string_or_io : String | IO) from_yaml
Constructor Detail
Creates a new Crypto::Bcrypt
object from the given password with salt and cost.
require "crypto/bcrypt"
password = Crypto::Bcrypt.new "secret", "salt_of_16_chars"
password.digest
Creates a new Crypto::Bcrypt
object from the given password with salt in bytes and cost.
require "crypto/bcrypt"
password = Crypto::Bcrypt.new "secret".to_slice, "salt_of_16_chars".to_slice
password.digest
Class Method Detail
Hashes the password using bcrypt algorithm using salt obtained via Random::Secure.random_bytes(SALT_SIZE)
.
require "crypto/bcrypt"
Crypto::Bcrypt.hash_secret "secret"
Instance Method Detail
Appends a String representation of this object which includes its class name, its object address and the values of all instance variables.
class Person
def initialize(@name : String, @age : Int32)
end
end
Person.new("John", 32).inspect # => #<Person:0x10fd31f20 @name="John", @age=32>
Appends a short String representation of this object which includes its class name and its object address.
class Person
def initialize(@name : String, @age : Int32)
end
end
Person.new("John", 32).to_s # => #<Person:0x10a199f20>