docs Do not promise constant-time at the hashing port

The port defines the check; the timing guarantee belongs to the adapter's comparison, not to the port. State that instead of asserting constant-time, which the port cannot guarantee.

Commit
40ac02a22d4481e4344a13a54d47d0d8a88c9335
Author
Marius Peter <dev@marius-peter.com>
Author date
Committer
Marius Peter <dev@marius-peter.com>
Committer date
lib/app/password_hash.mli
index f648d677..21c513bd 100644..100644
@@ -7,5 +7,6 @@
7 7 (** Salt and hash a new password into a stored verifier. *)
8 8
9 9 val verify : hash:string -> string -> bool
10 Removed: (** Constant-time check of a candidate password against a stored verifier. *)
10 Added: (** Check a candidate password against a stored verifier. The adapter supplies
11 Added: the comparison, so it decides the timing guarantee. *)
11 12 end