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Diffstat (limited to 'qemu/docs/ccid.txt')
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diff --git a/qemu/docs/ccid.txt b/qemu/docs/ccid.txt new file mode 100644 index 000000000..c7fda6d07 --- /dev/null +++ b/qemu/docs/ccid.txt @@ -0,0 +1,181 @@ +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:$PWD -o fake-smartcard-ca.cer -n fake-smartcard-ca + +and import it in the guest: + + certutil -A -d /etc/pki/nssdb -i fake-smartcard-ca.cer -t TC,TC,TC -n fake-smartcard-ca + +In a Linux guest you can then use the CoolKey PKCS #11 module to access +the card: + + certutil -d /etc/pki/nssdb -L -h all + +It will prompt you for the PIN (which is the password you assigned to the +certificate database early on), and then show you all three certificates +together with the manually imported CA cert: + + Certificate Nickname Trust Attributes + fake-smartcard-ca CT,C,C + John Doe:CAC ID Certificate u,u,u + John Doe:CAC Email Signature Certificate u,u,u + John Doe:CAC Email Encryption Certificate u,u,u + +If this does not happen, CoolKey is not installed or not registered with +NSS. Registration can be done from Firefox or the command line: + + modutil -dbdir /etc/pki/nssdb -add "CAC Module" -libfile /usr/lib64/pkcs11/libcoolkeypk11.so + modutil -dbdir /etc/pki/nssdb -list + + +5. Using ccid-card-passthru with client side hardware + +on the host specify the ccid-card-passthru device with a suitable chardev: + + qemu -chardev socket,server,host=0.0.0.0,port=2001,id=ccid,nowait -usb -device usb-ccid -device ccid-card-passthru,chardev=ccid + +on the client run vscclient, built when you built QEMU: + + vscclient <qemu-host> 2001 + + +6. Using ccid-card-passthru with client side certificates + +This case is not particularly useful, but you can use it to debug +your setup if #4 works but #5 does not. + +Follow instructions as per #4, except run QEMU and vscclient as follows: +Run qemu as per #5, and run vscclient from the "fake-smartcard" +directory as follows: + + qemu -chardev socket,server,host=0.0.0.0,port=2001,id=ccid,nowait -usb -device usb-ccid -device ccid-card-passthru,chardev=ccid + vscclient -e "db=\"sql:$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. + |