add time constraints and other checks on PC9x timestamp

[spider.git] / perl / DXProtHandle.pm

diff --git a/perl/DXProtHandle.pm b/perl/DXProtHandle.pm
index f18089ffaa07db020cfde2bb724ef7e65220cb7f..7839e11c55ea868a81a159aa395b28188c50d98c 100644 (file)
--- a/perl/DXProtHandle.pm
+++ b/perl/DXProtHandle.pm
@@ -43,17 +43,19 @@ use vars qw($pc11_max_age $pc23_max_age $last_pc50 $eph_restime $eph_info_restim
                        $investigation_int $pc19_version $myprot_version
                        %nodehops $baddx $badspotter $badnode $censorpc
                        $allowzero $decode_dk0wcy $send_opernam @checklist
-                       $eph_pc15_restime $pc9x_past_age $pc9x_future_age
+                       $eph_pc15_restime $pc9x_past_age
                        $pc10_dupe_age $pc92_slug_changes $last_pc92_slug
-                       $pc92Ain $pc92Cin $pc92Din $pc92Kin
+                       $pc92Ain $pc92Cin $pc92Din $pc92Kin $pc9x_time_tolerance
                   );
 
-$pc9x_past_age = 62*60;                        # maximum age in the past of a px9x (a config record might be the only
-                                                               # thing a node might send - once an hour)
-$pc9x_future_age = 2*3600;             # maximum age in the future ditto
 $pc10_dupe_age = 45;                   # just something to catch duplicate PC10->PC93 conversions
 $pc92_slug_changes = 60;               # slug any changes going outward for this long
 $last_pc92_slug = 0;                   # the last time we sent out any delayed add or del PC92s
+$pc9x_time_tolerance = 15*60;  # the time on a pc9x is allowed to be out by this amount
+$pc9x_past_age = (122*60)+             # maximum age in the past of a px9x (a config record might be the only
+       $pc9x_time_tolerance;           # thing a node might send - once an hour and we allow an extra hour for luck)
+                                # this is actually the partition between "yesterday" and "today" but old.
+
 
 # incoming talk commands
 sub handle_10
@@ -1478,6 +1480,21 @@ sub check_pc9x_t
        my $pc = shift;
        my $create = shift;
 
+       # check that the time is between 0 >= $t < 86400
+       unless ($t >= 0 && $t < 86400) {
+               dbg("PCPROT: time invalid t: $t, ignored") if isdbg('chanerr');
+               return undef;
+       }
+
+       # check that the time of this pc9x is within tolerance (default 15 mins either way)
+       my $now = $main::systime - $main::systime_daystart ;
+       my $diff = abs($now - $t);
+       unless ($diff < $pc9x_time_tolerance || 86400 - $diff < $pc9x_time_tolerance) {
+               my $c = ref $call ? $call->call : $call;
+               dbg("PC9XERR: $c time out of range t: $t now: $now diff: $diff > $pc9x_time_tolerance, ignored") if isdbg('chan');
+               return undef;
+       }
+
        my $parent = ref $call ? $call : Route::Node::get($call);
        if ($parent) {
                # we only do this for external calls whose routing table
@@ -1489,19 +1506,23 @@ sub check_pc9x_t
                        my $lastid = $parent->lastid;
                        if (defined $lastid) {
                                if ($t < $lastid) {
-                                       if ($t+86400-$lastid > $pc9x_past_age) {
+                                       # note that this is where we determine whether this pc9x has come in yesterday
+                                       # but is still greater (modulo 86400) than the lastid or is simply an old
+                                       # duplicate sentence. To determine this we need to do some module 86400
+                                       # arithmetic. High numbers mean that this is an old duplicate sentence,
+                                       # low numbers that it is a new sentence.
+                                       #
+                                       # Typically you will see yesterday being taken on $t = 84, $lastid = 86235
+                                       # and old dupes with $t = 234, $lastid = 256 (which give answers 249 and
+                                       # 86378 respectively in the calculation below).
+                                       #
+                                       if (($t-$lastid)%86400 > $pc9x_past_age) {
                                                dbg("PCPROT: dup id on $t <= lastid $lastid, ignored") if isdbg('chanerr') || isdbg('pc92dedupe');
                                                return undef;
                                        }
                                } elsif ($t == $lastid) {
                                        dbg("PCPROT: dup id on $t == lastid $lastid, ignored") if isdbg('chanerr') || isdbg('pc92dedupe');
                                        return undef;
-                               } else {
-                                       # $t > $lastid, check that the timestamp offered isn't too far away from 'now'
-                                       if ($t-$lastid > $pc9x_future_age ) {
-                                               dbg("PCPROT: id $t too far in the future of lastid $lastid, ignored") if isdbg('chanerr') || isdbg('pc92dedupe');
-                                               return undef;
-                                       }
                                }
                        }
                }
@@ -1510,7 +1531,7 @@ sub check_pc9x_t
        } else {
                return undef;
        }
-       if ('pc92dedupe') {
+       if (isdbg('pc92dedupe')) {
                my $exists = exists $parent->{lastid}; # naughty, naughty :-)
                my $val = $parent->{lastid};
                my $s = $exists ? (defined $val ? $val : 'exists/undef') : 'undef';