+register_format('pve-tfa-secret', \&pve_verify_tfa_secret);
+sub pve_verify_tfa_secret {
+ my ($key, $noerr) = @_;
+
+ # The old format used 16 base32 chars or 40 hex digits. Since they have a common subset it's
+ # hard to distinguish them without the our previous length constraints, so add a 'v2' of the
+ # format to support arbitrary lengths properly:
+ if ($key =~ /^v2-0x[0-9a-fA-F]{16,128}$/ || # hex
+ $key =~ /^v2-[A-Z2-7=]{16,128}$/ || # base32
+ $key =~ /^(?:[A-Z2-7=]{16}|[A-Fa-f0-9]{40})$/) # and the old pattern copy&pasted
+ {
+ return $key;
+ }
+
+ return undef if $noerr;
+
+ die "unable to decode TFA secret\n";
+}
+