rfc6287 1.0.2 · OCaml Package

RFC6287 (OCRA)

see http://tools.ietf.org/html/rfc6287
RFC6287

see https://www.rfc-editor.org/errata_search.php?eid=3729
Errata 3729

type t

The abstract OCRA suite type

type err =

| Invalid_suite_string
| DataInput of string
| Window of string

val t_of_string : string -> (t, err) Rresult.result

val string_of_t : t -> string

type di = {

c : bool;
(*
C
*)
q : [ `A | `N | `H ] * int;
(*
Q
*)
p : [ `SHA1 | `SHA256 | `SHA512 ] option;
(*
P
*)
s : int option;
(*
S
*)
t : int option;
(*
T
*)

}

val di_of_t : t -> di

returns
DataInput spec

val challenge : t -> string

returns
random challenge string q with format and length as specified in suite

type pinhash = [

| `String of string
| `Digest of Cstruct.t

]

if pinhash is `String x, gen and verify will apply the Pin Hash algorithm specified in suite to calculate the digest of x.

if pinhash is `Digest d, its length must equal digests size of Pin Hash function (as specified in suite)

type timestamp = [

| `Now
| `Int64 of int64

]

if timestamp is `Now, gen and verify will use Unix.time and the timestep specified in suite to calculate the timestamp value

val gen : 
  ?c:int64 ->
  ?p:pinhash ->
  ?s:Cstruct.t ->
  ?t:timestamp ->
  key:Cstruct.t ->
  q:string ->
  t ->
  (Cstruct.t, err) Rresult.result

Generate OCRA(K, {[C] | Q | [P | S | T]}).

returns
- Ok a the response
- Error (DataInput error_message) if parameters do not match suite

parameter c
DataInput C: Counter

parameter p
DataInput P: Pin Hash

parameter s
DataInput S: Session; length must equal session size (as specified in suite)

parameter t
DataInput T: Timestamp

parameter key
CryptoFunction key K

parameter q
DataInput Q: Challenge

val gen1 : 
  c:int64 option ->
  p:pinhash option ->
  s:Cstruct.t option ->
  t:timestamp option ->
  key:Cstruct.t ->
  q:string ->
  t ->
  (Cstruct.t, err) Rresult.result

val verify : 
  ?c:int64 ->
  ?p:pinhash ->
  ?s:Cstruct.t ->
  ?t:timestamp ->
  ?cw:int ->
  ?tw:int ->
  key:Cstruct.t ->
  q:string ->
  a:Cstruct.t ->
  t ->
  (bool * int64 option, err) Rresult.result

Verify OCRA Response.

returns
- Ok (true, None) upon successful verification for suite without C DataInput
- Ok (true, Some next_counter) upon successful verification for suite with C DataInput
- Ok (false, None) if verification failed
- Error (DataInput error_message) if parameters do not match suite
- Error (Window error_message) on invalid cw and tw parameters

parameter c
DataInput C: Counter

parameter p
DataInput P: Pin Hash

parameter s
DataInput S: Session; length must equal session size (as specified in suite)

parameter t
DataInput T: Timestamp

parameter cw
Counter Window

parameter tw
Timestamp Window

parameter key
CryptoFunction key K

parameter q
DataInput Q: Challenge

parameter a
Response to check against

val verify1 : 
  c:int64 option ->
  p:pinhash option ->
  s:Cstruct.t option ->
  t:timestamp option ->
  cw:int option ->
  tw:int option ->
  key:Cstruct.t ->
  q:string ->
  a:Cstruct.t ->
  t ->
  (bool * int64 option, err) Rresult.result

package rfc6287