Pull RLM_TOTP 6 digit commit in master to 3.2

[Peter Lambrechtsen]

Hi

Just trying to get the TOTP module working on 3.2.x using the latest RPM
package of 3.2.4.1

However noticed that the default config is 8 digits for the OTP Length in
the 3.2 branch

https://github.com/FreeRADIUS/freeradius-server/blob/v3.2.x/raddb/mods-available/totp

However this commit that was merged into master should be pulled into the
3.2 branch to default to 6 digits.

https://github.com/FreeRADIUS/freeradius-server/commit/534d165e71ec87a526e0e0f33a441666e5fd100a

If you wanted to follow the rfc6238 spec to the letter then the default is:

Hash: SHA1
Length: 6 Digits
Time-step Size: 30 Seconds

But I know there are various implementations that support:

Hash: SHA1 or SHA256
Digit: 6 or 8 Digits
Time-step Size: 30 or 60 Seconds

Additionally if hardware TOTP tokens are being used there is an issue where
the time set when manufactured can get wildly out of skew as I have had
more than one device that arrived that wasn't synced to UTC. The worst I
have seen was a hardware token over 3 minutes behind.

So if someone was looking to make changes in the module adding a per device
hardware skew with a set number of seconds plus or minus UTC such as:

TOTP-HardwareSkew = -180

Or similar to set the number of seconds the particular hardware token is
known to be out of skew.

I know patches are always welcome, but pulling the commit into 3.2 would be
appreciated.

Would you like me to raise an issue on Github about this? Or update
https://github.com/FreeRADIUS/freeradius-server/issues/4809

Cheers, Peter