Changes:

2.3.3: Ludovic Rousseau

2 April 2025

• Make polkit rules work again (bug introduced in 2.3.2)

Use case

"This is similar to the existing filtering support provided by PCSCLITE_FILTER_IGNORE_READER_NAMES (Remove and/or customize PC/SC reader names), but allows using the full range of udev rules to match specific devices. For example, if you have several Yubikeys and one is attached to a specific USB port that is being forwarded to a virtual machine (viz. it should not be touched by programs on the host machine), this facility allows setting a rule to keep pcscd away from that Yubikey. Yubikeys attached to other ports keep working normally."

udev

By default pcsc-lite uses libudev to detect readers events (plug or unplug of a USB reader). The idea is to use a flag set by udev to tell pcsc-lite to ignore a reader.

Example rule that targets a Yubikey attached to a specific USB port and causes pcscd to ignore that device:

ACTION!="remove|unbind", SUBSYSTEM=="usb", ATTR{idVendor}=="1050",
ATTR{idProduct}=="0406", KERNEL=="1-2.3", ENV{PCSCLITE_IGNORE}="1"

The KERNEL match targets a USB device attached to port 3 of a hub on port 2 of USB bus 1, and rule sets property PCSCLITE_IGNORE to cause the device to be ignored.

The reader with idVendor=0x1050 and idProduct=0x0406 is the YubiKey FIDO+CCID from Yubico.

Or if you want to ignore any reader connected to USB port 1-3:

ACTION!="remove|unbind", SUBSYSTEM=="usb", KERNEL=="1-3", ENV{PCSCLITE_IGNORE}="1"

You put the above rule is a file /etc/udev/rules.d/foobar.rules and voila.

Config

To know what value for KERNEL= to use you can run udevadm monitor and connect a USB reader. You will get something like:

$ udevadm monitor
monitor will print the received events for:
UDEV - the event which udev sends out after rule processing
KERNEL - the kernel uevent

KERNEL[2022.067560] add      /devices/pci0000:00/0000:00:14.0/usb1/1-3 (usb)
KERNEL[2022.069016] change   /devices/pci0000:00/0000:00:14.0/usb1/1-3 (usb)
KERNEL[2022.069332] add      /devices/pci0000:00/0000:00:14.0/usb1/1-3/1-3:1.0 (usb)
KERNEL[2022.069416] bind     /devices/pci0000:00/0000:00:14.0/usb1/1-3 (usb)
UDEV  [2022.690370] add      /devices/pci0000:00/0000:00:14.0/usb1/1-3 (usb)
UDEV  [2022.695881] change   /devices/pci0000:00/0000:00:14.0/usb1/1-3 (usb)
UDEV  [2022.700310] add      /devices/pci0000:00/0000:00:14.0/usb1/1-3/1-3:1.0 (usb)
UDEV  [2022.728691] bind     /devices/pci0000:00/0000:00:14.0/usb1/1-3 (usb)

You can see the "1-3" information to use in the .rules file.

Debug

To debug your configuration and check the new field PCSCLITE_IGNORE is correctly set you can use udevadm monitor --property and you get something like:

$ udevadm monitor --property
monitor will print the received events for:
UDEV - the event which udev sends out after rule processing
KERNEL - the kernel uevent

KERNEL[2265.405075] add      /devices/pci0000:00/0000:00:14.0/usb1/1-3 (usb)
ACTION=add
DEVPATH=/devices/pci0000:00/0000:00:14.0/usb1/1-3
SUBSYSTEM=usb
DEVNAME=/dev/bus/usb/001/015
DEVTYPE=usb_device
PRODUCT=8e6/3437/100
TYPE=0/0/0
BUSNUM=001
DEVNUM=015
SEQNUM=4692
MAJOR=189
MINOR=14

[...]

UDEV  [2266.066186] bind     /devices/pci0000:00/0000:00:14.0/usb1/1-3 (usb)
ACTION=bind
DEVPATH=/devices/pci0000:00/0000:00:14.0/usb1/1-3
SUBSYSTEM=usb
DEVNAME=/dev/bus/usb/001/015
DEVTYPE=usb_device
DRIVER=usb
PRODUCT=8e6/3437/100
TYPE=0/0/0
BUSNUM=001
DEVNUM=015
SEQNUM=4695
USEC_INITIALIZED=2265405122
ID_BUS=usb
ID_MODEL=USB_SmartCard_Reader
ID_MODEL_ENC=USB\x20SmartCard\x20Reader
ID_MODEL_ID=3437
ID_SERIAL=Gemplus_USB_SmartCard_Reader
ID_VENDOR=Gemplus
ID_VENDOR_ENC=Gemplus
ID_VENDOR_ID=08e6
ID_REVISION=0100
ID_USB_MODEL=USB_SmartCard_Reader
ID_USB_MODEL_ENC=USB\x20SmartCard\x20Reader
ID_USB_MODEL_ID=3437
ID_USB_SERIAL=Gemplus_USB_SmartCard_Reader
ID_USB_VENDOR=Gemplus
ID_USB_VENDOR_ENC=Gemplus
ID_USB_VENDOR_ID=08e6
ID_USB_REVISION=0100
ID_USB_INTERFACES=:0b0000:
ID_VENDOR_FROM_DATABASE=Gemalto (was Gemplus)
ID_MODEL_FROM_DATABASE=GemPC Twin SmartCard Reader
ID_PATH_WITH_USB_REVISION=pci-0000:00:14.0-usbv2-0:3
ID_PATH=pci-0000:00:14.0-usb-0:3
ID_PATH_TAG=pci-0000_00_14_0-usb-0_3
ID_SMARTCARD_READER=1
ID_FOR_SEAT=usb-pci-0000_00_14_0-usb-0_3
SYSTEMD_WANTS=smartcard.target
SYSTEMD_USER_WANTS=smartcard.target
PCSCLITE_IGNORE=1
MAJOR=189
MINOR=14
TAGS=:uaccess:security-device:seat:systemd:
CURRENT_TAGS=:uaccess:security-device:seat:systemd:

In pcscd logs I get:

04337722 [140613033731776] ../src/hotplug_libudev.c:656:HPEstablishUSBNotifications() USB Device add
00000411 [140613033731776] ../src/hotplug_libudev.c:299:get_driver() Looking for a driver for VID: 0x08E6, PID: 0x3437, path: /dev/bus/usb/001/016
00000303 [140613033731776] ../src/hotplug_libudev.c:417:HPAddDevice() Device Gemalto PC Twin Reader at /dev/bus/usb/001/016 (1-3:1.0) has PCSCLITE_IGNORE set: ignored

And I do not see the PC/SC reader with pcsc_scan command:

$ pcsc_scan -r
No reader found.

Conclusion

I am sure you will find other use cases for this new feature.

Thanks to Valtteri Vuorikoski for the patch. If you have ideas of changes or improvements for pcsc-lite do not hesitate to submit them.

Changes:

2.3.2: Ludovic Rousseau

26 March 2025

• Hardening systemd pcscd.service file

• pcscd.service: add missing Requires=polkit.service

• pcsc-spy: add missing PCSCv2_PART10_PROPERTY_* definitions

• Support udev PCSCLITE_IGNORE property to filter readers

• debuglog: force use of colors when --color is used

• Some other minor improvements

Changes:

1.7.3 - 22 March 2025, Ludovic ROUSSEAU

• 199 new ATRs

• meson:

  • add Windows support

  • add macOS support

  • add option to set ATRparser

• minor fixes and improvements

Changes:

1.6.2 - 19 March 2025, Ludovic Rousseau

• Add support of

  • Arculus AuthentiKey

  • BHDC Reader-HHD02

  • CHERRY Smart Terminal 1150

  • HSIC CCID-Reader

  • Ledger Flex

  • SYC USB CCID Reader

  • Thales RF CR2000

  • TOKEN2 FIDO2 Security Key(0026)

• Give more time to initialize the ACS ACR122U

• Do not build examples and contrib by default

• meson: add missing check for pthread_condattr_setclock

• Don't assume that all notifications are NotifySlotChange

• Hide unexported functions and variables

• Some other minor improvements

Since how long do you use smart cards?

I am surprised to have so many users of smart cards for such a long time.

Maybe I should have been more explicit in my question. I have been using smart cards myself since around 1990 with French public phone cards and bank cards as a normal user. My question was more, since when do you use smart cards as a professional?.

It is interesting to see very experienced smart card users and also all the possible groups of experiences.

Since how long do you read my blog?

This question has a trap. My blog started in 2000, so the oldest article is 15 years old. It is not possible to read it since more than 16 years.

The distribution of results is fairly even.

What is your activity?

With no real surprise, the vast majority of my readers are developers. This is not surprising since the majority of the blog content is about programs and programming interfaces.

In the "other" category, we have:

• sysadmin

• manufacturer

• functional and technical expert

• driver packager

How do you read/find my blog?

Many readers find the articles using a search engine. I guess it's the normal way to find a solution to a problem or some documentation.

I will continue to include references to my blog articles in the emails I send. I find that writing a blog article is a good way to not write again and again the same thing.

Few readers are using the RSS feed (but see RSS feed for my blog).

In the "other" category, we have:

• bookmark

• redirected by a colleague

• Firefox Update Scanner (maybe the RSS feed could be used instead?)

What content do you like?

No surprise, with a large part of developers, the main interest is in technical explanations and new software announcements.

I am happy to see that few people are looking for content about Windows issues.

Some people are looking for news about my holidays. That is nice, but I do not plan to share many photos here. Great game contest: Where was the picture below taken?

Free form

Thanks for your answers in the free forms.

What content would you like to find on my blog?

In no specific order:

• news about pcsc-lite

• more details about PC/SC and Smartcard

• sample code and technical explanations

  Yes, of course.

• more card specific stuff like reading passport information or discussing a bit about EMV processing

  My expertise lies more in PKI cards. I agree that it's interesting to have more details on common cards like EMV, passport or ID cards.

• chart of specifics/features/bugs between smartcard readers, cards and OS/driver versions

  You can find a list of readers you can't use at Disabled CCID readers and readers you should not use at Unsupported or partly supported CCID readers.

  I have never seen a really bogus smart card.

• your history with smart cards

  I started in the smart card industry in 1997. At first, it was difficult to use a smart card on a GNU/Linux system. I started by writing a driver for a serial smart card reader, then submitted patches to pcsc-lite and continued developing different smart card related software.

Conclusion

Do not expect posts about my holidays or my life.

I will continue to publish technical articles. If you know about a subject and want to share your knowledge, I am open to co-author articles. If you wrote a Free Software program or library that uses a smart card, I can take a look and write about it.

In any case you can contact me. My e-mail address is available from About me.

Changes:

2.2.1 (January 2025)

• patches from Ludovic Rousseau

  • waitforcardevent(): do not miss events between 2 calls

  • Use Windows locale to decode Unicode text

  • ACKS: add missing contributors

• patches from Kurt McKee

  • Test, fix, and simplify ATR parsing

Web hosting

Since May 2023 I host the blog myself (on my own server using my own domain name) and no more on Google blogger servers. I am very happy with this change.

Statistics

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Conclusion

Thank you to you, readers.

Do not hesitate to suggest new subjects, or tools, et caetera you would like to read about. See About me to contact me.

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