• Martin Kreichgauer's avatar
    device/fido/mac: set the User Present (UP) bit in authenticator data · 9be10b62
    Martin Kreichgauer authored
    See https://www.w3.org/TR/webauthn/#sec-authenticator-data. AFAIU, the
    spec is not exactly clear whether or not to set this bit from a user
    verifying authenticator. It says that the bit should be set if the
    user is "present", which is defined as having successfully completed a
    "user presence test". User presence test is defined separately from user
    verification test (which is what Touch ID does). Logically, a user
    verification test always includes a user presence test, but the spec
    doesn't say so explicitly.
    
    Regardless of what the spec says, setting both bits seems less likely to
    confuse server implementations IMO. A naive server e.g. might *just*
    check for the UP bit, and if it is not set reject the response, even
    though the UV bit is set. Hence, we should probably set both.
    
    Bug: 678128
    Change-Id: I02be366dba324e4f9b83ba0d354a674242fc72dc
    Reviewed-on: https://chromium-review.googlesource.com/1137216
    Commit-Queue: Martin Kreichgauer <martinkr@google.com>
    Reviewed-by: default avatarKim Paulhamus <kpaulhamus@chromium.org>
    Cr-Commit-Position: refs/heads/master@{#575386}
    9be10b62
util.mm 5.43 KB