linux-kernel - Re: [PATCH v3 1/3] usb: gadget: ccid: add support for USB CCID Gadget Device

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20180622164823.GA5351@gmail.com>
Date:   Fri, 22 Jun 2018 18:48:23 +0200
From:   Marcus Folkesson <marcus.folkesson@...il.com>
To:     Felipe Balbi <balbi@...nel.org>
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Jonathan Corbet <corbet@....net>, davem@...emloft.net,
        Mauro Carvalho Chehab <mchehab+samsung@...nel.org>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Randy Dunlap <rdunlap@...radead.org>,
        Ruslan Bilovol <ruslan.bilovol@...il.com>,
        Thomas Gleixner <tglx@...utronix.de>,
        Kate Stewart <kstewart@...uxfoundation.org>,
        linux-usb@...r.kernel.org, linux-doc@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH v3 1/3] usb: gadget: ccid: add support for USB CCID
 Gadget Device

Hi Filipe,

On Mon, Jun 18, 2018 at 11:22:04AM +0300, Felipe Balbi wrote:
> 
> Hi,
> 
> Marcus Folkesson <marcus.folkesson@...il.com> writes:
> > Hi Felipe,
> >
> > Should I send out v4 or what do you think?
> 
> sorry for the delay, have been busy with other tasks.
> 

It is no hurry :-)

> > On Wed, May 30, 2018 at 04:04:15PM +0200, Marcus Folkesson wrote:
> >> Hi Filipe,
> >> 
> >> On Wed, May 30, 2018 at 03:28:18PM +0300, Felipe Balbi wrote:
> >> > Marcus Folkesson <marcus.folkesson@...il.com> writes:
> >> > 
> >> > > Chip Card Interface Device (CCID) protocol is a USB protocol that
> >> > > allows a smartcard device to be connected to a computer via a card
> >> > > reader using a standard USB interface, without the need for each manufacturer
> >> > > of smartcards to provide its own reader or protocol.
> >> > >
> >> > > This gadget driver makes Linux show up as a CCID device to the host and let a
> >> > > userspace daemon act as the smartcard.
> >> > >
> >> > > This is useful when the Linux gadget itself should act as a cryptographic
> >> > > device or forward APDUs to an embedded smartcard device.
> >> > >
> >> > > Signed-off-by: Marcus Folkesson <marcus.folkesson@...il.com>
> >> > 
> >> > this could be done entirely in userspace with functionfs, why do we need
> >> > this part in the kernel? It does very little.
> >> 
> >> Andrzej pointed this out, and I actually do not have any good answer
> >> more than that the userspace application could be kept small and the
> >> important configuration of the CCID device is done with well (I hope)
> >> documented configfs attributes.
> 
> can we use existing open source applications without modification by
> accepting this glue layer?


If you mean existing open source application to talk to the "daemon", the answer is
yes. I have been using PCSC-lite and OpenSC on Linux, and PCSC on
Windows to communicate with the smartcard.

If you mean existing application as the "daemon", the answer is probably
no.

> 
> -- 
> balbi

Thanks,

Best regards
Marcus Folkesson