Re^2: converting tcpdump output

Another thing that I missed when running the code you mentioned is that POST payloads are getting stripped as well.

I managed to see the contents by commenting this line:

s/^\s+\S+\s+//; # remove initial address ind.
#s/\s{2}.*//;    # remove trailing dump  <-- commented
s/\s+//;
[download]

And redirecting the output to a file, then grepping it later. Is there a way of printing it along with the target?

EDIT: So far, I managed to get the values by modifying the regex line:

if (/^\S/) {
  while ($packet=~/(GET|POST|WWW-Authenticate|Authorization|[a-z]+=[a-
+z]+).+/g)  {
         ($sec,$min,$hour,$mday,$mon,$year,$wday,$yday,$isdst)=localti
+me(time);
[download]

Basically, I extended the regex to capture a string followed by "=" and then string again.

But as you can see, it's not a concise solution, since it gets a lot of rubbish as well.

Comment on Re^2: converting tcpdump output Select or Download Code

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Re^3: converting tcpdump output by RnC (Sexton) on May 18, 2005 at 11:29 UTC
Ok, I figured it out myself. Here's the complete code. #!/usr/bin/perl $\|=1; open (STDIN,"sudo /usr/sbin/tcpdump -lnx -s 1024 dst port 80 \|"); while (<>) { if (/^\S/) { while ($packet=~/(GET\|POST\|WWW-Authenticate\|Authorizat +ion\|Content-Length: \w+\s).+/g) { ($sec,$min,$hour,$mday,$mon,$year,$wday,$yday,$isdst)= +localtime(time); printf "%4d/%02d/%02d %02d:%02d:%02d",$year+1900,$mon+ +1,$mday,$hour,$min,$sec; print " - $client -> $host\t$&\n"; } undef $client; undef $host; undef $packet; ($client,$host) = /(\d+\.\d+\.\d+\.\d+\.\d+).+ > (\d+\.\d+\.\d ++\.\d+\.\d+)/ if /P \d+:\d+\((\d+)\)/ && $1 > 0; } next unless $client && $host; s/^\s+\S+\s+//; # remove initial address ind. s/\s{2}.//; # remove trailing dump s/\s+//; s/([0-9a-f]{2})\s?/chr(hex($1))/eg; tr/\x1F-\x7E\r\n//cd; $packet .= $_; } [download] Still not suitable, since it creates a line to just contain POST data, when it would be better if it appended the content to the end of a POST line, or something like that.	[reply] [d/l]

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Re^3: converting tcpdump output
by RnC (Sexton) on May 18, 2005 at 11:29 UTC

#!/usr/bin/perl

$|=1;

open (STDIN,"sudo /usr/sbin/tcpdump -lnx -s 1024 dst port 80 |");
while (<>) {
        if (/^\S/) {
                while ($packet=~/(GET|POST|WWW-Authenticate|Authorizat
+ion|Content-Length: \w+\s*).+/g)  {
                ($sec,$min,$hour,$mday,$mon,$year,$wday,$yday,$isdst)=
+localtime(time);
                printf "%4d/%02d/%02d %02d:%02d:%02d",$year+1900,$mon+
+1,$mday,$hour,$min,$sec;
                print " - $client -> $host\t$&\n";
        }
        undef $client; undef $host; undef $packet;

        ($client,$host) = /(\d+\.\d+\.\d+\.\d+\.\d+).+ > (\d+\.\d+\.\d
++\.\d+\.\d+)/
                if /P \d+:\d+\((\d+)\)/ && $1 > 0;

}
next unless $client && $host;
s/^\s+\S+\s+//; # remove initial address ind.
s/\s{2}.*//;    # remove trailing dump
s/\s+//;
s/([0-9a-f]{2})\s?/chr(hex($1))/eg;
tr/\x1F-\x7E\r\n//cd;
$packet .= $_;
}
[download]

Still

[reply]
[d/l]