EE Certificate Too Weak

If you are using some monitoring tools like Nagios, you might have run into this error – Cannot verify certificate: EE Certificate Too Weak. It means that the matching key is too short for todays standards. I found it myself when having SSL certificate check watching for expiring certs on iDRAC interface of Dell R510.

What is funny that it was happening only for 2 out of 3 of them and it wasn’t fixed by upgrading to the latest iDRAC version. You can’t set the key size from the web interface either. You need to use racadm either locally or via SSH session to iDRAC itself. First lets check the key size that’s currently set:

/admin1-> racadm getconfig -g cfgracsecurity -o cfgRacSecCsrKeySize

And then change it to bigger value and confirm:

/admin1-> racadm config -g cfgRacSecurity -o cfgRacSecCsrKeySize 2048
Object value modified successfully
/admin1-> racadm getconfig -g cfgracsecurity -o cfgRacSecCsrKeySize

After that you are ready to generale CSR again, this time with a longer key. Please note that this significantly increases time required for that task to finish, but it doesn’t affect performance of iDRAC interface later.

Using SoloKey on vanilla Ubuntu

It has been almost a year since last time I posted here so today we will have a quick one. I recently bought a SoloKey U2F key. It is a much cheaper and opensorce replacement for YubiKey (which is also a great product – I had a chance to use it for almost 2 years and it was flawless). In vanilla Ubuntu 18.04 when you plugin the key it gets detected correctly:

[Tue Feb 19 21:13:28 2019] usb 1-1: new full-speed USB device number 8 using xhci_hcd
[Tue Feb 19 21:13:28 2019] usb 1-1: New USB device found, idVendor=0483, idProduct=a2ca
[Tue Feb 19 21:13:28 2019] usb 1-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[Tue Feb 19 21:13:28 2019] usb 1-1: Product: Solo
[Tue Feb 19 21:13:28 2019] usb 1-1: Manufacturer: Solo Keys
[Tue Feb 19 21:13:28 2019] usb 1-1: SerialNumber: 0123456789ABCDEF
[Tue Feb 19 21:13:28 2019] hid-generic 0003:0483:A2CA.0008: hiddev1,hidraw3: USB HID v1.11 Device [Solo Keys Solo] on usb-0000:00:14.0-1/input0

Unfortunately permissions for device are incorrect and the key won’t be accessible from the browser:

$ ls -la /dev/hidraw*
crw------- 1 root root 243, 0 lut 19 21:03 hidraw0
crw------- 1 root root 243, 1 lut 19 21:03 hidraw1
crw------- 1 root root 243, 2 lut 19 21:03 hidraw2
crw------- 1 root root 243, 3 lut 19 21:13 hidraw3

To fix it we need a simple udev rule in /etc/udev/rules.d/90-solokey.rules:

KERNEL=="hidraw*", SUBSYSTEM=="hidraw", MODE="0664", GROUP="plugdev", ATTRS{idVendor}=="0483", ATTRS{idProduct}=="a2ca"

And then reload the udev rules:

sudo udevadm control --reload-rules

Thanks to that rule it will have group set to plugdev and read/write permissions for that device. By default user created in Ubuntu is a member of such group so it will work out of the box:

$ id
uid=1000(alchemyx) gid=1000(alchemyx) grupy=1000(alchemyx),4(adm),20(dialout),24(cdrom),27(sudo),30(dip),46(plugdev),116(lpadmin),126(sambashare),128(kismet)

Now you can test it by going to using Google Chrome. Click Next on first page and allow access to the key. The LED on SoloKey should turn amber and after clicking its hardware button it will get registered correctly.

If you want to do the same from the Firefox you need to reconfigure it first. Open about:config URL and confirm that you accept the risk. Find security.webauth.u2f there and flip it to True.