[minimega] smartcard support

Adding smartcard support to minimega. Work in progress -- Needs testing for physical smart cards and different types of emulated smart cards.

Only one smartcard per launched VM at a time. Supports both physical and emulated cards.

This pull request will not change minimega functionality outside of smart cards. Upon a call to vm smartcard add VM_NAME, a usb-ccid device will be added to the VM, as well as usb-smartcard-emulated.

A smart card reader (usb-ccid) is added on the first call of vm smartcard add and remains for the lifespan of the VM. Launched VMs that are not using smart cards will not have a reader attached during start up.

TODO

Test connecting physical smart card to machine running the experiment
Test different types of emulated smart cards
- The provided arguments are rigid -- making all parameters configurable would be a good idea
- internal/qmp/qmp.go line 480
Add ability to attach multiple smart cards at once
- Does this require multiple usb-ccid devices?
Update documentation

Commands

vm smartcard - display attached smartcards vm smartcard add VM_NAME - add a physical smart card (and CCID bus if connecting for the first time) vm smartcard add VM_NAME /path/to/smartcard - add an emulated (or fake) smartcard vm smartcard remove VM_NAME - disconnect the attached smartcard

Tests

On a VM, install the following packages:

pcscd pcsc-tools libnss3-tools opensc

To view attached smart cards (and CCID interfaces):

lsusb
- show connected USB devices (will show smart card reader after first smart card attached)
opensc-tool -l
- list all connected smart card readers
pcsc_scan
- shows connected smart card readers and cards. Runs continuously, you can see the card being added and removed

Launch a VM as normal

Create a fake smartcard (As seen in the QEMU CCID article)

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

Make sure pcscd is running and run pcsc_scan on vm
```
$ sudo systemctl restart pcscd
$ pcsc_scan
```

Attach smartcard to VM, verify card appears in vm

#minimega commands
vm smartcard add foo /path/to/fake-smartcard
vm smartcard remove foo

Resources

QEMU CCID

sandia-minimega / minimega