ligo/vendors/ocaml-pbkdf/src/pbkdf.ml
Grégoire Henry a1b30417e2 Fix indent
2018-02-20 18:29:56 +01:00

57 lines
2.1 KiB
OCaml

open Nocrypto
open Uncommon
module type S = sig
val pbkdf1 : password:Cstruct.t -> salt:Cstruct.t -> count:int -> dk_len:int -> Cstruct.t
val pbkdf2 : password:Cstruct.t -> salt:Cstruct.t -> count:int -> dk_len:int32 -> Cstruct.t
end
module Make (H: Hash.S) : S = struct
let pbkdf1 ~password ~salt ~count ~dk_len =
if Cstruct.len salt <> 8 then invalid_arg "salt should be 8 bytes"
else if count <= 0 then invalid_arg "count must be a positive integer"
else if dk_len <= 0 then invalid_arg "derived key length must be a positive integer"
else if dk_len > H.digest_size then invalid_arg "derived key too long"
else
let rec loop t = function
0 -> t
| i -> loop (H.digest t) (i - 1)
in
Cstruct.sub (loop (Cstruct.append password salt) count) 0 dk_len
let pbkdf2 ~password ~salt ~count ~dk_len =
if count <= 0 then invalid_arg "count must be a positive integer"
else if dk_len <= 0l then invalid_arg "derived key length must be a positive integer"
else
let h_len = H.digest_size
and dk_len = Int32.to_int dk_len in
let l = cdiv dk_len h_len in
let r = dk_len - (l - 1) * h_len in
let block i =
let rec f u xor = function
0 -> xor
| j -> let u = H.hmac ~key:password u in
f u (Cs.xor xor u) (j - 1)
in
let int_i = Cstruct.create 4 in
Cstruct.BE.set_uint32 int_i 0 (Int32.of_int i);
let u_1 = H.hmac ~key:password (Cstruct.append salt int_i) in
f u_1 u_1 (count - 1)
in
let rec loop blocks = function
0 -> blocks
| i -> loop ((block i)::blocks) (i - 1)
in
Cstruct.concat (loop [Cstruct.sub (block l) 0 r] (l - 1))
end
let pbkdf1 ~hash ~password ~salt ~count ~dk_len =
let module H = (val (Hash.module_of hash)) in
let module PBKDF = Make (H) in
PBKDF.pbkdf1 ~password ~salt ~count ~dk_len
let pbkdf2 ~prf ~password ~salt ~count ~dk_len =
let module H = (val (Hash.module_of prf)) in
let module PBKDF = Make (H) in
PBKDF.pbkdf2 ~password ~salt ~count ~dk_len