#!/usr/bin/perl
#############################################################################
# v3.2  Needs perl5 and w3m/lynx; edit path above to the location of your perl
#       install. Run as root the first time to setup the index
#       or change $indexpath
# This is a work in progress but i'm really happy with how easy it's
# made my life.   Written by Derrick Daugherty  freix/sifr  #unixgods /
# #solaris efnet.  bug fixes/suggestions mail me at rfc@dewn.com
#############################################################################
#              TO DO
# add diff url for html (-l) and txt's for -m/d/o etc
# add element to array for diff sites if they have leading 00's or not
# obey $PAGER?
# add extension for BCP/STD/FYI related rfc's only
# Add ICMP types
# clean up and optimize some
#
#############################################################################
# Feel free to redistribute as long as you keep this header in tact.
# http://www.dewn.com/rfc/
# Please let me know if you find this useful, I'd love to hear about it!
# rfc@dewn.com
#############################################################################
use strict;

# what to use for browsing. example: $viewer="/usr/local/bin/lynx";
# null will use @VIEWER to search your path for possibilities
# OR it will use the ENV var of RFCVIEWER
my $viewer;
# potential browsers, order of perference
my @VIEWER=qw(w3m lynx);

my ($servlength,$indexlength,$indexpath,$servpath);
my ($grepper,$rfcvar,$rfcbaseurl,$index);
my $homedir=glob("~/");

# These make it avail for all users if you can't 
# run it as root. (full path, not ~/ )
$indexpath="/usr/local/etc/rfc-index";
$servpath="/usr/local/etc/nmap-services";

####################################
## add as many urls as you please ##
####################################
my @URLS=qw(http://www.ietf.org/rfc/
	    http://www.faqs.org/rfc/
	    http://www.isi.edu/in-notes/
	    http://www.cis.ohio-state.edu/htbin/rfc/
	    /local/path/to/rfcs/);   #MAKE SURE you have the trailing slashes

#######################
## Setup working Env ##
#######################

my $RFCVIEWER=$ENV{'RFCVIEWER'};
my $PATH=$ENV{'PATH'};
my $PAGER=$ENV{'PAGER'};
my @PATH = split /\:/, $PATH;
my @PAGER = split /\:/, $PAGER;

if (not -e "$homedir.rfcrc")
   {`echo $URLS[0] > $homedir.rfcrc`;
       print "* * Creating $homedir.rfcrc * *\n\n";
       open (USERRC, "$homedir.rfcrc");
       while (<USERRC>) { $rfcbaseurl = $_;}
       close (USERRC);
   }
else {
      open (USERRC, "$homedir.rfcrc");
      chomp($rfcbaseurl=<USERRC>);
      close (USERRC);
     }

my $grepstring = $ARGV[0];
unless ($grepstring) {
	help();
}

if ($ARGV[0] ne "-i" and not -e "$indexpath")
   {print "\nNo rfc-index!!!  Run with the -i option to download it!\n"
    . "     (as root if you didn't change \$indexpath)\n"
        .       "usage: rfc -i    updates the $indexpath via \$viewer\n\n";exit}

## Find browser
if ($RFCVIEWER) {$viewer = $RFCVIEWER}
elsif (! -x $viewer and not $viewer)
  { $viewer = browser();
    if (not $viewer)
      { print "\n*** Couldn't find suitable browser!!! ***\n";
        print "Please set the \$viewer variable or \$RFCVIEWER env variable\n\n";
	$viewer = "**undefined**";
      }
  }

################################
# Run with the given arguemens #
################################

if ($ARGV[0] eq "-i") {
    open (INDEXPATH,">>$indexpath") || die "$indexpath can not be opened for writting!!\n" .
    "Please make sure the directory exists and you have\npermission to write to it!";
    close (INDEXPATH);
    $indexlength=numlines($indexpath);
    print "Modem users one moment, it's about 400k \(doesn't need to be updated often\)\n";
    print "original lines \t= $indexlength\t$indexpath\n";
    #system ("$viewer -dump http://www.faqs.org/rfc/rfc-index.txt > $indexpath");
    #system ("$viewer -dump http://www.dewn.com/rfc/rfc-index.txt > $indexpath");
    system ("$viewer -dump http://ftp.isi.edu/in-notes/rfc-index.txt > $indexpath");
    $indexlength=numlines($indexpath); print "new lines \t= $indexlength\t$indexpath\n";
    exit }

my ($grepmod,$caretmod);
    if (int($ARGV[0]) and ($ARGV[0] =~ /^\d+$/) ) {
       $grepmod = int($ARGV[0]);
    } else {
       $grepmod = int($ARGV[1]);
    }
    my $numdigits = length($grepmod);
    while ($numdigits < 4) {
       $grepmod = "0" . $grepmod;
       $numdigits++;
    }
    $caretmod = "^$grepmod";


if ($ARGV[0] =~ /^\d+$/) {
mygrep ($ARGV[0]);
}


if ($ARGV[0] eq "-d") {
    if ( (defined $ARGV[1]) and ($ARGV[1] =~ /^\d+$/) ){
     print "Making... $ARGV[2]rfc$grepmod.txt\n";
     system ("$viewer -dump $rfcbaseurl"."rfc$grepmod.txt > $ARGV[2]rfc$grepmod.txt");
        my $dumplength=numlines("$ARGV[2]rfc$grepmod.txt"); print "lines = $dumplength .. ";
     print "Done.\n";
     exit;
  } else { print "Must specify the RFC to dump!\n";
    print "\trfc -d \#  \/path\/-optional; dumps plain text RFC. default is current dir\n";
    exit } }

if ($ARGV[0] eq "-o") {
    if ( (defined $ARGV[1]) and ($ARGV[1] =~ /^\d+$/) ){
     print "Dumping... rfc$grepmod.txt\n";
     system ("$viewer -dump $rfcbaseurl"."rfc$grepmod.txt");
     print "Done.\n";
     exit;
  } else { print "Must specify the RFC to dump to STDOUT!\n";
    print "\trfc -o \#  dumps plain text RFC to STDOUT.\n";
    exit } }


if ($ARGV[0] eq "-r") {
  if (defined $ARGV[1]) {
    print "here's perl grep's argv $ARGV[1]\n";
	mygrepstrings($ARGV[1]);
  } else { print "Must give a regular expression in quotes!\n";
    print "\trfc -r    go wild with your own regexp on $indexpath\n";
    exit } }


if ($ARGV[0] eq "-k" or $ARGV[0] eq "-s") {
  if (defined $ARGV[1]) {
    mygrepstrings($ARGV[1]);
  } else { print "Must specify a string to search for!\n";
    print "\trfc $ARGV[0] search for specified string in $indexpath\n";
    exit } }


if ($ARGV[0] eq "-l") {
  if (defined $ARGV[1] and ($ARGV[1] =~ /^\d+$/)) {
    print "Found browser at $viewer\n";
    exec "$viewer $rfcbaseurl"."rfc$grepmod.txt";
 } else {print "Need to specify the RFC to display!\n";
     print "\trfc -l \#  spawns $viewer to the specified RFC\n"; exit }}


### email the rfc

if ($ARGV[0] eq "-m") {
    if (( $ARGV[1] =~ /^\d+$/) and defined $ARGV[2]) {
     print "Retreiving rfc$grepmod.txt...\n";
     open(RFC,"$viewer -dump $rfcbaseurl"."rfc$grepmod.txt |");
     print "Mailing $ARGV[2]\n";
     open(MAIL, "| sendmail -t ");
     print MAIL "To: $ARGV[2]\n";

     	if ($ARGV[3]) 
	{ 
	 my $i=3;
	 my $subject;
	 while ($i <= $#ARGV)
	   { $subject = join " ", ($subject, $ARGV[$i]); $i++ }
	print MAIL "Subject:$subject\n";
	}
     	else {print MAIL "Subject: RFCutil:- $rfcbaseurl"."rfc$grepmod.txt\n"}

     	#if ($ARGV[3]) { print MAIL "Subject: $ARGV[3]\n"}
     	#else {print MAIL "Subject: RFCutil:- $rfcbaseurl"."rfc$grepmod.txt\n"}
     print MAIL "This was generated and sent to you by the RFCutil\nhttp://www.dewn.com/rfc/\n";
     print MAIL "\n\n\n$rfcbaseurl"."rfc$grepmod.txt";
     while (<RFC>) { print MAIL; }
        close (MAIL);
        close (RFC);
     exit;
  }else { print "Must specify the RFC and email addy!!\n";
    print "\trfc -m \# user\@remote.net [opt subject]; emails the RFC to given address\n";
    exit } }


if ($ARGV[0] eq "-n") {
	if ($ARGV[1] ne "-i" and not -e "$servpath")
	   {print "\nNo $servpath!!! Run with the -n -i option to download it!\n"
	    . "     (as root if you didn't change \$servpath)\n"
		.       "usage: \`rfc -n -i\` updates the $servpath via $viewer\n\n";exit}
    if (defined $ARGV[1]) {
	if ($ARGV[1] eq "-i") {
	    open (SERVPATH, ">>$servpath"); close (SERVPATH);
	    my $servlength=numlines("$servpath");
	    print "One moment, it's fairly small \(doesn't need to be updated often\)\n";
	    print "original lines \t= $servlength\t$servpath\n";
	    system ("$viewer -dump http://www.dewn.com/rfc/nmap-services > $servpath");
	    my $servlength=numlines("$servpath"); print "new lines \t= $servlength\t$servpath\n";
	    exit}
     print "Looking up service...\n";
     my $string = $ARGV[1];
     chomp($string);
  open (SERVINDEX, $servpath);
     my $place;
     foreach $place (<SERVINDEX>) {
   	if ($place =~ /(.*$string.+)/i){ 
   	print "$1\n";}
   	}
   close (SERVINDEX);
        exit;
  } else { print "Must specify the port number\/service that you're looking for!!\n";
    print "\trfc -n \#\/daemon local search for non-stanard service/port nums\n\t(BO Netbus etc)\n";
    exit } }


if ($ARGV[0] eq "-u") {
    if (defined $ARGV[1] and $ARGV[1]=~ /^\d+$/) {
     my $url=($ARGV[1] - 1);
     `echo $URLS[$url] > $homedir.rfcrc`;
     print "BaseURL is $URLS[$url]\n";
     exit;
    } else { print "Must specify a \# of the webserver listed in -w !!\n";
   print "\trfc -u \#  sets the base URL to the number listed with -w\n";
   print "BaseURL is $rfcbaseurl\n";
exit}}


if ($ARGV[0] eq "-w") {
   print "Use -u # to set the URL\n";
   my $list;
   my $placement = 1;
   foreach $list (@URLS){
   print "$placement) $list\n";
   $placement++;
   }
   print "BaseURL is $rfcbaseurl\n";
   exit  }

if ($ARGV[0] eq "-p") {
   rfc1700($ARGV[1],$ARGV[2],$ARGV[3]);
   print "\n";
   exit  }


if ($ARGV[0] eq "-h") {
 help();
}



sub mygrep
{

    if (int($_[0]) and ($_[0] =~ /^\d+$/) ) {
       $grepmod = int($_[0]);
    } else {
       $grepmod = int($_[1]);
    }
    my $numdigits = length($grepmod);
    while ($numdigits < 4) {
       $grepmod = "0" . $grepmod;
       $numdigits++;
    }
    $caretmod = "^$grepmod";

open (RFCINDEX, $indexpath);
  # This will get us where we're going...
  while (<RFCINDEX>) {
	#next if (!/^$grepmod/);
	next if (!/$caretmod/);
	print "The Result:\n$_";
	last; }
  # Roll through the rest of the lines and print.
  while (<RFCINDEX>) {
	last if (/^$/);
	print; }
close (RFCINDEX);
}

sub mygrepstrings
  {
    my ($thing,$line);
    my $found = 0;
    my ($lookingfor) = @_;
    print "The Result:\n";
    open (RFCINDEX, $indexpath);
        foreach $line (<RFCINDEX>) 
	{
	    if ($line !~ /^\s*$/){
	        $thing .= $line; 
	        if ($line =~ /$lookingfor/i) {
		    $found = 1;  	     }
	    }
	   else { 
		  if ($found) { 
			#print $thing,"\n";
			print $thing;
	    		      }
		$thing = ""; $found = 0;
		}
	}
    close (RFCINDEX);
  }

sub browser
{
   #print "checking for a suitable browser\n";
   my $possibility; 
   foreach $viewer (@VIEWER)
     {
        foreach $possibility (@PATH)
          {
           if (-x "$possibility/" . "$viewer")
            { $viewer = "$possibility/"."$viewer"; return $viewer}
          }
     }
}

sub numlines
{
 my $lines=0;
  open (COUNTFILE, "$_[0]");
   my $i=0;
   foreach $lines (<COUNTFILE>)
    { $i++; }
  close (COUNTFILE);
 return $i;
}

my
($looking_for,$start,$end,$search_proto,$url,$search_port,$line,$name,$port,$proto,$descript,$last_line_match,$number,$keyword,$desc,$references,$local_refs,$send_of_refs,$local_ref,$found,$end_of_refs);
my @refs;
my @local_refs;

sub rfc1700                  #THANKS to Derek J. Balling for this!!!!
{

    $looking_for = shift @_;

    if ($looking_for eq "ip")
    {
    $start = "Assigned Internet Protocol Numbers";
    $end = "REFERENCES";
    ($search_proto) = @_;
    #$url = "ftp://ftp.isi.edu/in-notes/iana/assignments/protocol-numbers";
    $url = "http://ftp.isi.edu/in-notes/iana/assignments/protocol-numbers";
   print "Making connection to server.... \n$url\n";
    }
    elsif ($looking_for eq "port")
    {
    $start = "Port Assignments:";
    $end = "REFERENCES";
    ($search_port,$search_proto) = @_;
    #$url = "ftp://ftp.isi.edu/in-notes/iana/assignments/port-numbers";
    $url = "http://ftp.isi.edu/in-notes/iana/assignments/port-numbers";
   print "Making connection to server.... \n$url\n";
    }
    else
    {
    print "Usage: rfc -p port <port num> [protocol]\n";
    print "       rfc -p ip <proto num>\n";
    exit 1;
    }

    open RFC, "$viewer -dump $url |";

    while (<RFC>)
    {
    last if /^$start/;
    }

    while (<RFC>)
    {
    last if /$end/;

    $line = $_;

    if ($looking_for eq "port")
    {
        ($name,$port,$proto,$descript) = $line =~ /^(.*)\s+(\d+)\/(\w+)\s+(.*)/;
        if (
        ( ($port =~ /^\d+$/) and ($port eq $search_port) )
        or
        ( ($search_port =~ /\D/) and
          ( ($name =~ /$search_port/i) or ($descript =~ /$search_port/i) )
          )
        )
        {
        $last_line_match = 1;
        if ( (!defined $search_proto) or ($proto eq $search_proto) )
        {
            print $line;
        }
        }
        else
        {
        if ( ($line =~ /^\#/) and ($last_line_match) )
        {
            print $line;
        }
        else
        {
            $last_line_match = 0;
        }
        }
    }

    if ($looking_for eq "ip")
    {
        ($number,$keyword,$desc,$references) = $line =~ /^\s*([\d\-]+)\s+([A-Z\-\d]+)\s+(.*?)\s*\[(.*)\]/;

        if ( ($search_proto =~ /^\d+$/) and ($search_proto == $number) )
        {
        print $line;
        @local_refs = split /\,/, $references;
        push @refs, @local_refs;
        }
        elsif ( ($search_proto =~ /\D/) and
            ( ($keyword =~ /$search_proto/i) or ($desc =~ /$search_proto/i) )
            )
        {
        print $line;
        @local_refs = split /\,/, $references;
        push @refs, @local_refs;
        }
    }

    }

    if ($looking_for eq 'ip')
    {
    print "\n";
    # Find IP refs

    $end_of_refs = "URL =";

    while (<RFC>)
    {
        last if /$end_of_refs/;

        $line = $_;
        ($local_ref) = /^\[(.*?)\]/;
        if ($local_ref)
        {
        if (grep /^$local_ref$/, @refs)
        {
            $found = 1;
            print $line;
        }
        else
        {
            $found = 0;
        }
        }
        else
        {
        if ( ($found) and (/\w/))
        {
            print;
        }
        else
        {
            $found = 0;
        }
        }
    }
    }

    close RFC;

}

sub help 
{

 print  "rfc v3.2: perl util to search the rfc-index and disply the pages with \$viewer\n"
    .   "usage:  rfc \#     search rfc-index for specified RFC and list topic\n"
        .       "\trfc -d \# \/path\/ (optional) dumps plain text RFC. default is current dir\n"
        .       "\trfc -h    displays this stuff\n"
        .       "\trfc -i    updates the $indexpath via \$viewer\n"
        .       "\trfc -k    keyword; same as -s\n"
        .       "\trfc -l \#  spawns \$viewer to the specified RFC\n"
        .       "\trfc -m \# user\@remote.net [opt subject]; emails the RFC to given address\n"
        .       "\trfc -n \#\/daemon local search for non-standard service/port nums\n\t\t  (BO, Netbus, etc)\n"
        .       "\trfc -o \#  Dumps RFC to STDOUT\n"
        .       "\trfc -p    Connect to INI's assigned numbers for proto nums or \n\t\t  services/ports association\n"
        .       "\trfc -r    go wild with your own regexp on rfc-index\n"
        .       "\trfc -s \"string\" Search the index for specific string\n"
        .       "\trfc -u \#  sets the base URL to the number listed with -w\n"
        .       "\trfc -w    lists the available webservers to display\n"
        .       "baseURL=$rfcbaseurl\n"
    .   "comments\/bugfixes mailto: rfc\@dewn.com\n\n";
   exit;

}