Adding upstream version 4.96.upstream/4.96upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 159 insertions, 0 deletions

diff --git a/util/ratelimit.pl b/util/ratelimit.pl
new file mode 100644
index 0000000..e212fa2
--- /dev/null
+++ b/util/ratelimit.pl
@@ -0,0 +1,159 @@
+#!/usr/bin/perl -wT
+
+use strict;
+
+BEGIN { pop @INC if $INC[-1] eq '.' };
+
+sub usage () {
+  print <<END;
+usage: ratelimit.pl [options] <period> <regex> <logfile>
+
+The aim of this script is to compute clients' peak sending rates
+from an Exim log file, using the same formula as Exim's ratelimit
+ACL condition. This is so that you can get an idea of a reasonable
+limit setting before you deploy the restrictions.
+
+options:
+
+-d          Show debugging information to stderr
+-p          Show progress of parse the log to stderr
+
+<period>    The smoothing period in seconds, as defined by the
+            documentation for the ratelimit ACL condition.
+
+            This script isn't perfectly accurate, because the time
+            stamps in Exim's log files are only accurate to a second
+            whereas internally Exim computes sender rates to the
+            accuracy of your computer's clock (typically 10ms).
+
+<regex>     The second argument is a regular expression.
+
+            Each line is matched against the regular expression.
+            Lines that do not match are ignored. The regex may
+            contain 0, 1, or 2 () capturing sub-expressions.
+
+            If there are no () sub-expressions, then every line that
+            matches is used to compute a single rate. Its maximum
+            value is reported when the script finishes.
+
+            If there is one () sub-expression, then the text matched
+            by the sub-expression is used to identify a rate lookup
+            key, similar to the lookup key used by the ratelimit
+            ACL condition. For example, you might write a regex
+            to match the client IP address, or the authenticated
+            username. Separate rates are computed for each different
+            client and the maximum rate for each client is reported
+            when the script finishes.
+
+            If there are two () sub-expressions, then the text matched
+            by the first sub-expression is used to identify a rate
+            lookup key as above, and the second is used to match the
+            message size recorded in the log line, e.g. "S=(\\d+)".
+            In this case the byte rate is computed instead of the
+            message rate, similar to the per_byte option of the
+            ratelimit ACL condition.
+
+<logfile>   The log files to be processed can be specified on the
+            command line after the other arguments; if no filenames
+            are specified the script will read from stdin.
+
+examples:
+
+./ratelimit.pl 1 ' <= .*? \[(.*?)\]' <logfile>
+
+            Compute burst sending rate like ACL condition
+            ratelimit = 0 / 1s / strict / \$sender_host_address
+
+./ratelimit.pl 3600 '<= (.*?) ' <logfile>
+
+            Compute sending rate like ACL condition
+            ratelimit = 0 / 1h / strict / \$sender_address
+
+END
+  exit 1;
+}
+
+sub iso2unix (@) {
+  my ($y,$m,$d,$H,$M,$S,$zs,$zh,$zm) = @_;
+  use integer;
+  $y -= $m < 3;
+  $m += $m < 3 ? 10 : -2;
+  my $z = defined $zs ? "${zs}1" * ($zh * 60 + $zm) : 0;
+  my $t = $y/400 - $y/100 + $y/4 + $y*365
+        + $m*367/12 + $d - 719499;
+  return $t * 86400
+       + $H * 3600
+       + $M * 60
+       + $S
+       - $z;
+}
+
+my $debug = 0;
+my $progress = 0;
+while (@ARGV && $ARGV[0] =~ /^-\w+$/) {
+  $debug = 1    if $ARGV[0] =~ s/(-\w*)d(\w*)/$1$2/;
+  $progress = 1 if $ARGV[0] =~ s/(-\w*)p(\w*)/$1$2/;
+  shift if $ARGV[0] eq "-";
+}
+
+usage if @ARGV < 2;
+
+my $progtime = "";
+
+my $period = shift;
+
+my $re_txt = shift;
+my $re = qr{$re_txt}o;
+
+my %time;
+my %rate;
+my %max;
+
+sub debug ($) {
+  my $key = shift;
+  printf STDERR "%s\t%12d %8s %5.2f %5.2f\n",
+    $_, $time{$key}, $key, $max{$key}, $rate{$key};
+}
+
+while (<>) {
+  next unless $_ =~ $re;
+  my $key = $1 || "";
+  my $size = $2 || 1.0;
+  my $time = iso2unix
+    ($_ =~ m{^(\d{4})-(\d\d)-(\d\d)[ ]
+              (\d\d):(\d\d):(\d\d)[ ]
+              (?:([+-])(\d\d)(\d\d)[ ])?
+            }x);
+  if ($progress) {
+    my $prog_now = substr $_, 0, 14;
+    if ($progtime ne $prog_now) {
+      $progtime = $prog_now;
+      print STDERR "$progtime\n";
+    }
+  }
+  if (not defined $time{$key}) {
+    $time{$key} = $time;
+    $rate{$key} = 0.0;
+    $max{$key} = 0.0;
+    debug $key if $debug;
+    next;
+  }
+  # see acl_ratelimit() for details of the following
+  my $interval = $time - $time{$key};
+  $interval = 1e-9 if $interval <= 0.0;
+  my $i_over_p = $interval / $period;
+  my $a = exp(-$i_over_p);
+  $time{$key} = $time;
+  $rate{$key} = $size * (1.0 - $a) / $i_over_p + $a * $rate{$key};
+  $max{$key} = $rate{$key} if $rate{$key} > $max{$key};
+  debug $key if $debug;
+}
+
+print map {
+  " " x (20 - length) .
+  "$_ : $max{$_}\n"
+} sort {
+  $max{$a} <=> $max{$b}
+} keys %max;
+
+# eof