#!/usr/bin/perl # A simple web server that just listens for textarea filter requests # and runs an editor to manipulate the text. Is intended to be # used with the TextAid extention for Chrome. # # NOTE: If you use this on a shared system, you should configure TextAid # with a username & password and make sure that the saved authorization # config file stays secret! use strict; use warnings; use threads; use Socket; use IO::Select; use File::Temp; use Getopt::Long; # If you don't want to require authentication, set $REQUIRE_AUTH to 0. # When it is set to 1, the first authenticated request that is received # will be saved to the $SAVE_AUTH_FILE file. All subsequent requests # are compared to that value. To change your password, just remove the # file and make a new edit-server request using the new auth info. our $REQUIRE_AUTH = 1; our $SAVE_AUTH_FILE = "$ENV{HOME}/.edit-server-auth"; # Only accept requests from something that claims to be a chrome-extension. # Set this to 0 if you want other things to be able to use this script. our $REQUIRE_CHROME_EXTENSION = 1; # Configures the port we listen on and if we allow only localhost requests. our $PORT = 8888; our $LOCALHOST_ONLY = 1; # Configure the program that you want to run to handle the requests. # This editor invocation must NOT return control to this script until # you are done editing. our $EDITOR_CMD = '/home/users/nico/bin/vim-term "%s"'; #our $EDITOR_CMD = '/usr/bin/emacsclient -c "%s"'; # The settings to configure the temp dir and how soon old files are removed. # If TMPTEMPLATE contains the string -URL64-, then up to 64 chars of the munged # URL for the textarea's page will be included in the tmp file's filename. our $TMPDIR = "$ENV{HOME}/.tmp"; our $TMPTEMPLATE = 'edit-server-URL64-XXXXXX'; our $TMPSUFFIX = '.txt'; our $CLEAN_AFTER_HOURS = 4; &Getopt::Long::Configure('bundling'); GetOptions( 'verbose|v+' => \( my $verbosity = 0 ), 'help|h' => \( my $help_opt ), ) or usage(); usage() if $help_opt; umask 0077; # Disables all "group" and "other" perms when saving files. $| = 1; local *S; socket(S, PF_INET, SOCK_STREAM , getprotobyname('tcp')) or die "couldn't open socket: $!\n"; setsockopt(S, SOL_SOCKET, SO_REUSEADDR, 1); if ($LOCALHOST_ONLY) { bind(S, sockaddr_in($PORT, INADDR_LOOPBACK)); } else { bind(S, sockaddr_in($PORT, INADDR_ANY)); } listen(S, 5) or die "listen failed: $!\n"; my $sel = IO::Select->new(); $sel->add(*S); while (1) { my @con = $sel->can_read(); foreach my $con (@con) { my $fh; my $remote = accept($fh, $con); my($port, $iaddr) = sockaddr_in($remote); my $addr = inet_ntoa($iaddr); my $t = threads->create(\&do_edit, $fh); $t->detach(); } } exit; # Read the text from the content body, edit it, and write it back as our output. sub do_edit { my($fh) = @_; binmode $fh; local $_ = <$fh>; my($method, $path, $ver) = /^(GET|HEAD|POST)\s+(.*?)\s+(HTTP\S+)/; print "Path: $path\n" if $verbosity >= 1; unless (defined $ver) { http_header($fh, 500, 'Invalid request.'); close $fh; return; } if ($method ne 'POST') { http_header($fh, 200, 'OK', 'Server is up and running. To use it, issue a POST request with the file to edit as the content body.'); close $fh; return; } my %header; while (<$fh>) { s/\r?\n$//; last if $_ eq ''; my($name, $value) = /^(.*?): +(.*)/; $header{lc($name)} = $value; print "Header: \L$name\E = $value\n" if $verbosity >= 2; } print "-------------------------------------------------------------------\n" if $verbosity >= 2; if ($REQUIRE_AUTH) { my $authorized; my $auth = $header{authorization}; # e.g. "Basic 01234567890ABCDEF==" if (defined $auth) { my $line; if (open AUTH, '<', $SAVE_AUTH_FILE) { chomp($line = ); close AUTH; } elsif ($!{ENOENT} && open AUTH, '>', $SAVE_AUTH_FILE) { # The first request w/o an auth file saves the auth info. print AUTH $auth, "\n"; close AUTH; $line = $auth; } else { http_header($fh, 501, 'Internal failure -- auth-file failed.'); close $fh; return; } if ($line eq $auth) { $authorized = 1; } } unless ($authorized) { http_header($fh, 401, 'Unauthorized!'); close $fh; return; } } if ($REQUIRE_CHROME_EXTENSION) { my $origin = $header{origin}; unless (defined $origin && $origin =~ /^chrome-extension:/) { http_header($fh, 401, 'Unauthorized.'); close $fh; return; } } my $len = $header{'content-length'}; unless (defined $len && $len =~ /^\d+$/) { http_header($fh, 500, 'Invalid request -- no content-length.'); close $fh; return; } my $got = read($fh, $_, $len); if ($got != $len) { http_header($fh, 500, 'Invalid request -- wrong content-length.'); close $fh; return; } my($query) = $path =~ /\?(.+)/; (my $template_fn = $TMPTEMPLATE) =~ s/-URL(\d+)-/ '-' . url_filename($query, $1) . '-' /e; my $tmp = new File::Temp( TEMPLATE => $template_fn, DIR => $TMPDIR, SUFFIX => $TMPSUFFIX, UNLINK => 0, ); my $name = $tmp->filename; print $tmp $_; close $tmp; my $cmd = sprintf($EDITOR_CMD, $name); system $cmd; unless (open FILE, '<', $name) { http_header($fh, 500, "Unable to re-open $name: $!"); close $fh; return; } http_header($fh, 200, 'OK', ''); print $fh ; close FILE; close $fh; # Clean-up old tmp files that have been around for a few hours. if (opendir(DP, $TMPDIR)) { (my $match = quotemeta($TMPTEMPLATE . $TMPSUFFIX)) =~ s/(.*[^X])(X+)/ $1 . ('\w' x length($2)) /e; $match =~ s/\\-URL\d+\\-/-.*-/; print "Match: $match\n" if $verbosity >= 3; foreach my $fn (grep /^$match$/o, readdir DP) { $fn = "$TMPDIR/$fn"; print "Fn: $fn\n" if $verbosity >= 3; my $age = -M $fn; if ($age > $CLEAN_AFTER_HOURS/24) { unlink $fn; } else { print "Age: $age\n" if $verbosity >= 3; } } closedir DP; } } sub http_header { my $fh = shift; my $status = shift; my $status_txt = shift; @_ = $status_txt unless @_; print $fh "HTTP/1.0 $status $status_txt\r\n", "Server: edit-server\r\n", "Content-Type: text/plain\r\n", "\r\n", @_; } sub url_filename { my($query, $max_chars) = @_; print "Query: $query\n" if $verbosity >= 4; if (defined $query) { foreach my $var_val (split /&/, $query) { my($var, $val) = split /=/, $var_val, 2; if ($var eq 'url') { print "Before: $val\n" if $verbosity >= 4; $val =~ s/\%([0-9a-fA-F]{2})/ chr hex $1 /eg; $val =~ s{^https?://}{}; $val =~ s/[^-\w.]+/_/g; $val =~ s/^(.{1,$max_chars}).*/$1/; print "After: $val\n" if $verbosity >= 4; return $val; } } } return 'unknown-url'; } sub usage { die <