Guestbook
A guestbook is an early use of CGI to provide a way for website visitors to leave a trace on a page, typically in the form of a short message, like signing a physical "guestbook" (a practice still in use in art galleries, weddings, and funerals). As these early scripts typically allowed text (and possibly HTML markup) to be anonymously attached to a page, the guestbook goes hand in hand with the development of online spam practices.
See: wikipedia:Guestbook, wikipedia:Guestbook spam
Examples
Example: Code
An example guestbook written by Matthew Wright, written in the PERL language. (Source: http://www.scriptarchive.com/guestbook.html)
#!/usr/bin/perl
##############################################################################
# Guestbook Version 2.3.1 #
# Copyright 1996 Matt Wright mattw@scriptarchive.com #
# Created 4/21/95 Last Modified 10/29/95 #
# Scripts Archive at: http://www.scriptarchive.com/ #
##############################################################################
# COPYRIGHT NOTICE #
# Copyright 1996 Matthew M. Wright All Rights Reserved. #
# #
# Guestbook may be used and modified free of charge by anyone so long as #
# this copyright notice and the comments above remain intact. By using this #
# code you agree to indemnify Matthew M. Wright from any liability that #
# might arise from it's use. #
# #
# Selling the code for this program without prior written consent is #
# expressly forbidden. In other words, please ask first before you try and #
# make money off of my program. #
# #
# Obtain permission before redistributing this software over the Internet or #
# in any other medium. In all cases copyright and header must remain intact.#
##############################################################################
# Set Variables
$guestbookurl = "http://your.host.com/~yourname/guestbook.html";
$guestbookreal = "/home/yourname/public_html/guestbook.html";
$guestlog = "/home/yourname/public_html/guestlog.html";
$cgiurl = "http://your.host.com/cgi-bin/guestbook.pl";
$date_command = "/usr/bin/date";
# Set Your Options:
$mail = 0; # 1 = Yes; 0 = No
$uselog = 1; # 1 = Yes; 0 = No
$linkmail = 1; # 1 = Yes; 0 = No
$separator = 1; # 1 = <hr>; 0 = <p>
$redirection = 0; # 1 = Yes; 0 = No
$entry_order = 1; # 1 = Newest entries added first;
# 0 = Newest Entries added last.
$remote_mail = 0; # 1 = Yes; 0 = No
$allow_html = 1; # 1 = Yes; 0 = No
$line_breaks = 0; # 1 = Yes; 0 = No
# If you answered 1 to $mail or $remote_mail you will need to fill out
# these variables below:
$mailprog = '/usr/lib/sendmail';
$recipient = 'you@your.com';
# Done
##############################################################################
# Get the Date for Entry
$date = `$date_command +"%A, %B %d, %Y at %T (%Z)"`; chop($date);
$shortdate = `$date_command +"%D %T %Z"`; chop($shortdate);
# Get the input
read(STDIN, $buffer, $ENV{'CONTENT_LENGTH'});
# Split the name-value pairs
@pairs = split(/&/, $buffer);
foreach $pair (@pairs) {
($name, $value) = split(/=/, $pair);
# Un-Webify plus signs and %-encoding
$value =~ tr/+/ /;
$value =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C", hex($1))/eg;
$value =~ s/<!--(.|\n)*-->//g;
if ($allow_html != 1) {
$value =~ s/<([^>]|\n)*>//g;
}
$FORM{$name} = $value;
}
# Print the Blank Response Subroutines
&no_comments unless $FORM{'comments'};
&no_name unless $FORM{'realname'};
# Begin the Editing of the Guestbook File
open (FILE,"$guestbookreal") || die "Can't Open $guestbookreal: $!\n";
@LINES=<FILE>;
close(FILE);
$SIZE=@LINES;
# Open Link File to Output
open (GUEST,">$guestbookreal") || die "Can't Open $guestbookreal: $!\n";
for ($i=0;$i<=$SIZE;$i++) {
$_=$LINES[$i];
if (/<!--begin-->/) {
if ($entry_order eq '1') {
print GUEST "<!--begin-->\n";
}
if ($line_breaks == 1) {
$FORM{'comments'} =~ s/\cM\n/<br>\n/g;
}
print GUEST "<b>$FORM{'comments'}</b><br>\n";
if ($FORM{'url'}) {
print GUEST "<a href=\"$FORM{'url'}\">$FORM{'realname'}</a>";
}
else {
print GUEST "$FORM{'realname'}";
}
if ( $FORM{'username'} ){
if ($linkmail eq '1') {
print GUEST " \<<a href=\"mailto:$FORM{'username'}\">";
print GUEST "$FORM{'username'}</a>\>";
}
else {
print GUEST " <$FORM{'username'}>";
}
}
print GUEST "<br>\n";
if ( $FORM{'city'} ){
print GUEST "$FORM{'city'},";
}
if ( $FORM{'state'} ){
print GUEST " $FORM{'state'}";
}
if ( $FORM{'country'} ){
print GUEST " $FORM{'country'}";
}
if ($separator eq '1') {
print GUEST " - $date<hr>\n\n";
}
else {
print GUEST " - $date<p>\n\n";
}
if ($entry_order eq '0') {
print GUEST "<!--begin-->\n";
}
}
else {
print GUEST $_;
}
}
close (GUEST);
# Log The Entry
if ($uselog eq '1') {
&log('entry');
}
#########
# Options
# Mail Option
if ($mail eq '1') {
open (MAIL, "|$mailprog $recipient") || die "Can't open $mailprog!\n";
print MAIL "Reply-to: $FORM{'username'} ($FORM{'realname'})\n";
print MAIL "From: $FORM{'username'} ($FORM{'realname'})\n";
print MAIL "Subject: Entry to Guestbook\n\n";
print MAIL "You have a new entry in your guestbook:\n\n";
print MAIL "------------------------------------------------------\n";
print MAIL "$FORM{'comments'}\n";
print MAIL "$FORM{'realname'}";
if ( $FORM{'username'} ){
print MAIL " <$FORM{'username'}>";
}
print MAIL "\n";
if ( $FORM{'city'} ){
print MAIL "$FORM{'city'},";
}
if ( $FORM{'state'} ){
print MAIL " $FORM{'state'}";
}
if ( $FORM{'country'} ){
print MAIL " $FORM{'country'}";
}
print MAIL " - $date\n";
print MAIL "------------------------------------------------------\n";
close (MAIL);
}
if ($remote_mail eq '1' && $FORM{'username'}) {
open (MAIL, "|$mailprog -t") || die "Can't open $mailprog!\n";
print MAIL "To: $FORM{'username'}\n";
print MAIL "From: $recipient\n";
print MAIL "Subject: Entry to Guestbook\n\n";
print MAIL "Thank you for adding to my guestbook.\n\n";
print MAIL "------------------------------------------------------\n";
print MAIL "$FORM{'comments'}\n";
print MAIL "$FORM{'realname'}";
if ( $FORM{'username'} ){
print MAIL " <$FORM{'username'}>";
}
print MAIL "\n";
if ( $FORM{'city'} ){
print MAIL "$FORM{'city'},";
}
if ( $FORM{'state'} ){
print MAIL " $FORM{'state'}";
}
if ( $FORM{'country'} ){
print MAIL " $FORM{'country'}";
}
print MAIL " - $date\n";
print MAIL "------------------------------------------------------\n";
close (MAIL);
}
# Print Out Initial Output Location Heading
if ($redirection eq '1') {
print "Location: $guestbookurl\n\n";
}
else {
&no_redirection;
}
#######################
# Subroutines
sub no_comments {
print "Content-type: text/html\n\n";
print "<html><head><title>No Comments</title></head>\n";
print "<body><h1>Your Comments appear to be blank</h1>\n";
print "The comment section in the guestbook fillout form appears\n";
print "to be blank and therefore the Guestbook Addition was not\n";
print "added. Please enter your comments below.<p>\n";
print "<form method=POST action=\"$cgiurl\">\n";
print "Your Name:<input type=text name=\"realname\" size=30 ";
print "value=\"$FORM{'realname'}\"><br>\n";
print "E-Mail: <input type=text name=\"username\"";
print "value=\"$FORM{'username'}\" size=40><br>\n";
print "City: <input type=text name=\"city\" value=\"$FORM{'city'}\" ";
print "size=15>, State: <input type=text name=\"state\" ";
print "value=\"$FORM{'state'}\" size=15> Country: <input type=text ";
print "name=\"country\" value=\"$FORM{'country'}\" size=15><p>\n";
print "Comments:<br>\n";
print "<textarea name=\"comments\" COLS=60 ROWS=4></textarea><p>\n";
print "<input type=submit> * <input type=reset></form><hr>\n";
print "Return to the <a href=\"$guestbookurl\">Guestbook</a>.";
print "\n</body></html>\n";
# Log The Error
if ($uselog eq '1') {
&log('no_comments');
}
exit;
}
sub no_name {
print "Content-type: text/html\n\n";
print "<html><head><title>No Name</title></head>\n";
print "<body><h1>Your Name appears to be blank</h1>\n";
print "The Name Section in the guestbook fillout form appears to\n";
print "be blank and therefore your entry to the guestbook was not\n";
print "added. Please add your name in the blank below.<p>\n";
print "<form method=POST action=\"$cgiurl\">\n";
print "Your Name:<input type=text name=\"realname\" size=30><br>\n";
print "E-Mail: <input type=text name=\"username\"";
print " value=\"$FORM{'username'}\" size=40><br>\n";
print "City: <input type=text name=\"city\" value=\"$FORM{'city'}\" ";
print "size=15>, State: <input type=text name=\"state\" ";
print "value=\"$FORM{'state'}\" size=2> Country: <input type=text ";
print "value=USA name=\"country\" value=\"$FORM{'country'}\" ";
print "size=15><p>\n";
print "Comments have been retained.<p>\n";
print "<input type=hidden name=\"comments\" ";
print "value=\"$FORM{'comments'}\">\n";
print "<input type=submit> * <input type=reset><hr>\n";
print "Return to the <a href=\"$guestbookurl\">Guestbook</a>.";
print "\n</body></html>\n";
# Log The Error
if ($uselog eq '1') {
&log('no_name');
}
exit;
}
# Log the Entry or Error
sub log {
$log_type = $_[0];
open (LOG, ">>$guestlog");
if ($log_type eq 'entry') {
print LOG "$ENV{'REMOTE_HOST'} - [$shortdate]<br>\n";
}
elsif ($log_type eq 'no_name') {
print LOG "$ENV{'REMOTE_HOST'} - [$shortdate] - ERR: No Name<br>\n";
}
elsif ($log_type eq 'no_comments') {
print LOG "$ENV{'REMOTE_HOST'} - [$shortdate] - ERR: No ";
print LOG "Comments<br>\n";
}
}
# Redirection Option
sub no_redirection {
# Print Beginning of HTML
print "Content-Type: text/html\n\n";
print "<html><head><title>Thank You</title></head>\n";
print "<body><h1>Thank You For Signing The Guestbook</h1>\n";
# Print Response
print "Thank you for filling in the guestbook. Your entry has\n";
print "been added to the guestbook.<hr>\n";
print "Here is what you submitted:<p>\n";
print "<b>$FORM{'comments'}</b><br>\n";
if ($FORM{'url'}) {
print "<a href=\"$FORM{'url'}\">$FORM{'realname'}</a>";
}
else {
print "$FORM{'realname'}";
}
if ( $FORM{'username'} ){
if ($linkmail eq '1') {
print " <<a href=\"mailto:$FORM{'username'}\">";
print "$FORM{'username'}</a>>";
}
else {
print " <$FORM{'username'}>";
}
}
print "<br>\n";
if ( $FORM{'city'} ){
print "$FORM{'city'},";
}
if ( $FORM{'state'} ){
print " $FORM{'state'}";
}
if ( $FORM{'country'} ){
print " $FORM{'country'}";
}
print " - $date<p>\n";
# Print End of HTML
print "<hr>\n";
print "<a href=\"$guestbookurl\">Back to the Guestbook</a>\n"; print "- You may need to reload it when you get there to see your\n";
print "entry.\n";
print "</body></html>\n";
exit;
}