[mirror_qemu.git] / docs / ccid.txt

QEMU CCID Device Documentation.

Contents
1. USB CCID device
2. Building
3. Using ccid-card-emulated with hardware
4. Using ccid-card-emulated with certificates
5. Using ccid-card-passthru with client side hardware
6. Using ccid-card-passthru with client side certificates
7. Passthrough protocol scenario
8. libcacard

1. USB CCID device

The USB CCID device is a USB device implementing the CCID specification, which
lets one connect smart card readers that implement the same spec. For more
information see the specification:

 Universal Serial Bus
 Device Class: Smart Card
 CCID
 Specification for
 Integrated Circuit(s) Cards Interface Devices
 Revision 1.1
 April 22rd, 2005

Smartcards are used for authentication, single sign on, decryption in
public/private schemes and digital signatures. A smartcard reader on the client
cannot be used on a guest with simple usb passthrough since it will then not be
available on the client, possibly locking the computer when it is "removed". On
the other hand this device can let you use the smartcard on both the client and
the guest machine. It is also possible to have a completely virtual smart card
reader and smart card (i.e. not backed by a physical device) using this device.

2. Building

The cryptographic functions and access to the physical card is done via NSS.

Installing NSS:

In redhat/fedora:
    yum install nss-devel
In ubuntu/debian:
    apt-get install libnss3-dev
    (not tested on ubuntu)

Configuring and building:
    ./configure --enable-smartcard && make


3. Using ccid-card-emulated with hardware

Assuming you have a working smartcard on the host with the current
user, using NSS, qemu acts as another NSS client using ccid-card-emulated:

    qemu -usb -device usb-ccid -device ccid-card-emulated


4. Using ccid-card-emulated with certificates stored in files

You must create the CA and card certificates. This is a one time process.
We use NSS certificates:

    mkdir fake-smartcard
    cd fake-smartcard
    certutil -N -d sql:$PWD
    certutil -S -d sql:$PWD -s "CN=Fake Smart Card CA" -x -t TC,TC,TC -n fake-smartcard-ca
    certutil -S -d sql:$PWD -t ,, -s "CN=John Doe" -n id-cert -c fake-smartcard-ca
    certutil -S -d sql:$PWD -t ,, -s "CN=John Doe (signing)" --nsCertType smime -n signing-cert -c fake-smartcard-ca
    certutil -S -d sql:$PWD -t ,, -s "CN=John Doe (encryption)" --nsCertType sslClient -n encryption-cert -c fake-smartcard-ca

Note: you must have exactly three certificates.

You can use the emulated card type with the certificates backend:

    qemu -usb -device usb-ccid -device ccid-card-emulated,backend=certificates,db=sql:$PWD,cert1=id-cert,cert2=signing-cert,cert3=encryption-cert

To use the certificates in the guest, export the CA certificate:

    certutil -L -r -d sql:$PWD -o fake-smartcard-ca.cer -n fake-smartcard-ca

and import it in the guest:

    certutil -A -d /etc/pki/nssdb -i fake-smartcard-ca.cer -t TC,TC,TC -n fake-smartcard-ca

In a Linux guest you can then use the CoolKey PKCS #11 module to access
the card:

    certutil -d /etc/pki/nssdb -L -h all

It will prompt you for the PIN (which is the password you assigned to the
certificate database early on), and then show you all three certificates
together with the manually imported CA cert:

    Certificate Nickname                        Trust Attributes
    fake-smartcard-ca                           CT,C,C
    John Doe:CAC ID Certificate                 u,u,u
    John Doe:CAC Email Signature Certificate    u,u,u
    John Doe:CAC Email Encryption Certificate   u,u,u

If this does not happen, CoolKey is not installed or not registered with
NSS.  Registration can be done from Firefox or the command line:

    modutil -dbdir /etc/pki/nssdb -add "CAC Module" -libfile /usr/lib64/pkcs11/libcoolkeypk11.so
    modutil -dbdir /etc/pki/nssdb -list


5. Using ccid-card-passthru with client side hardware

on the host specify the ccid-card-passthru device with a suitable chardev:

    qemu -chardev socket,server=on,host=0.0.0.0,port=2001,id=ccid,wait=off \
         -usb -device usb-ccid -device ccid-card-passthru,chardev=ccid

on the client run vscclient, built when you built QEMU:

    vscclient <qemu-host> 2001


6. Using ccid-card-passthru with client side certificates

This case is not particularly useful, but you can use it to debug
your setup if #4 works but #5 does not.

Follow instructions as per #4, except run QEMU and vscclient as follows:
Run qemu as per #5, and run vscclient from the "fake-smartcard"
directory as follows:

    qemu -chardev socket,server=on,host=0.0.0.0,port=2001,id=ccid,wait=off \
         -usb -device usb-ccid -device ccid-card-passthru,chardev=ccid
    vscclient -e "db=\"sql:$PWD\" use_hw=no soft=(,Test,CAC,,id-cert,signing-cert,encryption-cert)" <qemu-host> 2001


7. Passthrough protocol scenario

This is a typical interchange of messages when using the passthru card device.
usb-ccid is a usb device. It defaults to an unattached usb device on startup.
usb-ccid expects a chardev and expects the protocol defined in
cac_card/vscard_common.h to be passed over that.
The usb-ccid device can be in one of three modes:
 * detached
 * attached with no card
 * attached with card

A typical interchange is: (the arrow shows who started each exchange, it can be client
originated or guest originated)

client event      |      vscclient           |    passthru    |     usb-ccid  |  guest event
----------------------------------------------------------------------------------------------
                  |      VSC_Init            |                |               |
                  |      VSC_ReaderAdd       |                |     attach    |
                  |                          |                |               |  sees new usb device.
card inserted ->  |                          |                |               |
                  |      VSC_ATR             |   insert       |     insert    |  see new card
                  |                          |                |               |
                  |      VSC_APDU            |   VSC_APDU     |               | <- guest sends APDU
client<->physical |                          |                |               |
card APDU exchange|                          |                |               |
client response ->|      VSC_APDU            |   VSC_APDU     |               |  receive APDU response
                                                    ...
                                    [APDU<->APDU repeats several times]
                                                    ...
card removed  ->  |                          |                |               |
                  |      VSC_CardRemove      |   remove       |    remove     |   card removed
                                                    ...
                                    [(card insert, apdu's, card remove) repeat]
                                                    ...
kill/quit         |                          |                |               |
  vscclient       |                          |                |               |
                  |      VSC_ReaderRemove    |                |    detach     |
                  |                          |                |               |   usb device removed.


8. libcacard

Both ccid-card-emulated and vscclient use libcacard as the card emulator.
libcacard implements a completely virtual CAC (DoD standard for smart
cards) compliant card and uses NSS to retrieve certificates and do
any encryption.  The backend can then be a real reader and card, or
certificates stored in files.

For documentation of the library see docs/libcacard.txt.
Commit	Line	Data
6576b74b	1	QEMU CCID Device Documentation.
1056c02b AL	2
	3	Contents
	4	1. USB CCID device
	5	2. Building
	6	3. Using ccid-card-emulated with hardware
	7	4. Using ccid-card-emulated with certificates
	8	5. Using ccid-card-passthru with client side hardware
	9	6. Using ccid-card-passthru with client side certificates
	10	7. Passthrough protocol scenario
	11	8. libcacard
	12
	13	1. USB CCID device
	14
	15	The USB CCID device is a USB device implementing the CCID specification, which
	16	lets one connect smart card readers that implement the same spec. For more
	17	information see the specification:
	18
	19	Universal Serial Bus
	20	Device Class: Smart Card
	21	CCID
	22	Specification for
	23	Integrated Circuit(s) Cards Interface Devices
	24	Revision 1.1
	25	April 22rd, 2005
	26
e03ba136	27	Smartcards are used for authentication, single sign on, decryption in
1056c02b AL	28	public/private schemes and digital signatures. A smartcard reader on the client
	29	cannot be used on a guest with simple usb passthrough since it will then not be
	30	available on the client, possibly locking the computer when it is "removed". On
	31	the other hand this device can let you use the smartcard on both the client and
	32	the guest machine. It is also possible to have a completely virtual smart card
	33	reader and smart card (i.e. not backed by a physical device) using this device.
	34
	35	2. Building
	36
	37	The cryptographic functions and access to the physical card is done via NSS.
	38
	39	Installing NSS:
	40
	41	In redhat/fedora:
	42	yum install nss-devel
	43	In ubuntu/debian:
	44	apt-get install libnss3-dev
	45	(not tested on ubuntu)
	46
	47	Configuring and building:
	48	./configure --enable-smartcard && make
	49
471f7e30	50
1056c02b AL	51	3. Using ccid-card-emulated with hardware
	52
	53	Assuming you have a working smartcard on the host with the current
	54	user, using NSS, qemu acts as another NSS client using ccid-card-emulated:
	55
5f32804c	56	qemu -usb -device usb-ccid -device ccid-card-emulated
1056c02b	57
1056c02b	58
471f7e30 PB	59	4. Using ccid-card-emulated with certificates stored in files
	60
	61	You must create the CA and card certificates. This is a one time process.
	62	We use NSS certificates:
1056c02b	63
471f7e30 PB	64	mkdir fake-smartcard
	65	cd fake-smartcard
	66	certutil -N -d sql:$PWD
	67	certutil -S -d sql:$PWD -s "CN=Fake Smart Card CA" -x -t TC,TC,TC -n fake-smartcard-ca
	68	certutil -S -d sql:$PWD -t ,, -s "CN=John Doe" -n id-cert -c fake-smartcard-ca
	69	certutil -S -d sql:$PWD -t ,, -s "CN=John Doe (signing)" --nsCertType smime -n signing-cert -c fake-smartcard-ca
	70	certutil -S -d sql:$PWD -t ,, -s "CN=John Doe (encryption)" --nsCertType sslClient -n encryption-cert -c fake-smartcard-ca
1056c02b AL	71
	72	Note: you must have exactly three certificates.
	73
471f7e30 PB	74	You can use the emulated card type with the certificates backend:
	75
	76	qemu -usb -device usb-ccid -device ccid-card-emulated,backend=certificates,db=sql:$PWD,cert1=id-cert,cert2=signing-cert,cert3=encryption-cert
	77
	78	To use the certificates in the guest, export the CA certificate:
	79
	80	certutil -L -r -d sql:$PWD -o fake-smartcard-ca.cer -n fake-smartcard-ca
	81
	82	and import it in the guest:
	83
	84	certutil -A -d /etc/pki/nssdb -i fake-smartcard-ca.cer -t TC,TC,TC -n fake-smartcard-ca
	85
	86	In a Linux guest you can then use the CoolKey PKCS #11 module to access
	87	the card:
	88
	89	certutil -d /etc/pki/nssdb -L -h all
	90
	91	It will prompt you for the PIN (which is the password you assigned to the
	92	certificate database early on), and then show you all three certificates
	93	together with the manually imported CA cert:
	94
	95	Certificate Nickname Trust Attributes
	96	fake-smartcard-ca CT,C,C
	97	John Doe:CAC ID Certificate u,u,u
	98	John Doe:CAC Email Signature Certificate u,u,u
	99	John Doe:CAC Email Encryption Certificate u,u,u
	100
	101	If this does not happen, CoolKey is not installed or not registered with
	102	NSS. Registration can be done from Firefox or the command line:
	103
	104	modutil -dbdir /etc/pki/nssdb -add "CAC Module" -libfile /usr/lib64/pkcs11/libcoolkeypk11.so
	105	modutil -dbdir /etc/pki/nssdb -list
1056c02b	106
1056c02b AL	107
	108	5. Using ccid-card-passthru with client side hardware
	109
	110	on the host specify the ccid-card-passthru device with a suitable chardev:
	111
c2387413 DB	112	qemu -chardev socket,server=on,host=0.0.0.0,port=2001,id=ccid,wait=off \
c2387413 DB	113	-usb -device usb-ccid -device ccid-card-passthru,chardev=ccid
1056c02b	114
471f7e30 PB	115	on the client run vscclient, built when you built QEMU:
	116
	117	vscclient <qemu-host> 2001
	118
1056c02b AL	119
	120	6. Using ccid-card-passthru with client side certificates
	121
471f7e30 PB	122	This case is not particularly useful, but you can use it to debug
	123	your setup if #4 works but #5 does not.
	124
	125	Follow instructions as per #4, except run QEMU and vscclient as follows:
	126	Run qemu as per #5, and run vscclient from the "fake-smartcard"
	127	directory as follows:
	128
c2387413 DB	129	qemu -chardev socket,server=on,host=0.0.0.0,port=2001,id=ccid,wait=off \
c2387413 DB	130	-usb -device usb-ccid -device ccid-card-passthru,chardev=ccid
471f7e30	131	vscclient -e "db=\"sql:$PWD\" use_hw=no soft=(,Test,CAC,,id-cert,signing-cert,encryption-cert)" <qemu-host> 2001
1056c02b	132
1056c02b AL	133
	134	7. Passthrough protocol scenario
	135
	136	This is a typical interchange of messages when using the passthru card device.
	137	usb-ccid is a usb device. It defaults to an unattached usb device on startup.
	138	usb-ccid expects a chardev and expects the protocol defined in
	139	cac_card/vscard_common.h to be passed over that.
	140	The usb-ccid device can be in one of three modes:
	141	* detached
	142	* attached with no card
	143	* attached with card
	144
	145	A typical interchange is: (the arrow shows who started each exchange, it can be client
	146	originated or guest originated)
	147
	148	client event \| vscclient \| passthru \| usb-ccid \| guest event
	149	----------------------------------------------------------------------------------------------
	150	\| VSC_Init \| \| \|
	151	\| VSC_ReaderAdd \| \| attach \|
	152	\| \| \| \| sees new usb device.
	153	card inserted -> \| \| \| \|
	154	\| VSC_ATR \| insert \| insert \| see new card
	155	\| \| \| \|
	156	\| VSC_APDU \| VSC_APDU \| \| <- guest sends APDU
	157	client<->physical \| \| \| \|
	158	card APDU exchange\| \| \| \|
	159	client response ->\| VSC_APDU \| VSC_APDU \| \| receive APDU response
	160	...
	161	[APDU<->APDU repeats several times]
	162	...
	163	card removed -> \| \| \| \|
	164	\| VSC_CardRemove \| remove \| remove \| card removed
	165	...
	166	[(card insert, apdu's, card remove) repeat]
	167	...
	168	kill/quit \| \| \| \|
	169	vscclient \| \| \| \|
	170	\| VSC_ReaderRemove \| \| detach \|
	171	\| \| \| \| usb device removed.
	172
	173
	174	8. libcacard
	175
471f7e30 PB	176	Both ccid-card-emulated and vscclient use libcacard as the card emulator.
	177	libcacard implements a completely virtual CAC (DoD standard for smart
	178	cards) compliant card and uses NSS to retrieve certificates and do
	179	any encryption. The backend can then be a real reader and card, or
	180	certificates stored in files.
1056c02b	181
471f7e30	182	For documentation of the library see docs/libcacard.txt.
1056c02b	183