How to make the platform send authenticatorGetInfo command

Bling Chiang

unread,

Mar 15, 2019, 5:25:29 AM3/15/19

to FIDO Dev (fido-dev)

I try to create an Authenticator with CTAPHID(HID over USB) protocol connected to the platform

Now I can Register and Login with CTAP1(U2F) protocol on the website https://webauthn.org/.

Howerver, I want to try CTAP2 protocol and the platform doesn't send authenticatorGetInfo command.

The first command when I Press the Register button is CTAPHID_INIT command.

How to make the platform send authenticatorGetInfo command and communicate with the Authenticator using CTAP2 protocol

Thank you!

Dao Thanh Long

unread,

Mar 18, 2019, 11:50:08 PM3/18/19

to Bling Chiang, FIDO Dev (fido-dev)

Hi Bling Chiang

authenticatorGetInfo is sub-command, CTAPHID_CBOR is mandatory-command.

So, I think that "Capabilities flag" parameter (in CTAPHID_INIT) must be set to CAPABILITY_CBOR

Thanks and Best regard!

Dao Thanh Long Mr.

Software Engineer

Headquarters: 12th Floor, TTC Tower, 19 Duy Tan, Cau Giay, Hanoi, Vietnam Tel: (+84-24) 6266 2703 (ext: 000)
Branch: 7th Floor, Thien Sơn Building, 5 Nguyen Gia Thieu, Ward 6, District 3, Hochiminh City Tel: (+84-28) 3930 5023

Factories:

Hanoi: Lot 40, Quang Minh IZ, Me Linh Tel: (+84-24) 3813 4646
Hochiminh City: Lot I3-3, N2 Street, Saigon Hi-Tech Park, District 9 Tel: (+84-28) 3736 1446

Vào Th 6, 15 thg 3, 2019 vào lúc 16:25 Bling Chiang <blin...@gmail.com> đã viết:

--
You received this message because you are subscribed to the Google Groups "FIDO Dev (fido-dev)" group.
To unsubscribe from this group and stop receiving emails from it, send an email to fido-dev+u...@fidoalliance.org.
To post to this group, send email to fido...@fidoalliance.org.
Visit this group at https://groups.google.com/a/fidoalliance.org/group/fido-dev/.
To view this discussion on the web visit https://groups.google.com/a/fidoalliance.org/d/msgid/fido-dev/65888a1c-ffb2-483b-932a-ffd03ab5be06%40fidoalliance.org.

Ackermann Yuriy

unread,

Mar 19, 2019, 6:09:52 AM3/19/19

to Dao Thanh Long, Bling Chiang, FIDO Dev (fido-dev)

First in HID you need establish session by sending CTAPHID_INIT. You then extract NewCID and generate request frame.

Then you can start sending other message types, such as CTAPHID_CBOR, which is used for sending CTAP2 cmds.

The CTAP2 specs says that CTAP2 request consists of CMD(1 byte) + DATA, so for getInfo it is 0x04 for CMD and nothing for data, since GetInfo does not need corresponding data.

So you need to send HID packed, on new CID, with HID cmd set to CTAPHID_CBOR, and it contains 1 bytes payload of 0x04.

Example would be: 0102030490000104

01020304 - example newCID that you recover from INIT.

90 - 0x80(HID CMD PREFIX) + 0x10(CTAPHID_CBOR) - HID CMD

0001 - BCNT - 1 byte payload

04 - GetInfo

Regards. Yuriy

Yuriy Ackermann

FIDO, Identity, Standards

skype: ackermann.yuriy

github: @herrjemand

twitter: @herrjemand

medium: @herrjemand

To view this discussion on the web visit https://groups.google.com/a/fidoalliance.org/d/msgid/fido-dev/CAJ1kOgqrb6N%3DrPWWOnsbeE6MkmBrcB4Di9Kw24BGGYNMUz3jgg%40mail.gmail.com.

Reply all

Reply to author

Forward