-# Copyright (C) 2016-2020 all contributors <meta@public-inbox.org>
+# Copyright (C) all contributors <meta@public-inbox.org>
# License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
# For retrieving attachments from messages in the WWW interface
package PublicInbox::WwwAttach; # internal package
use strict;
+use v5.10.1;
use parent qw(PublicInbox::GzipFilter);
-use bytes (); # only for bytes::length
-use PublicInbox::EmlContentFoo qw(parse_content_type);
use PublicInbox::Eml;
+sub referer_match ($) {
+ my ($ctx) = @_;
+ my $env = $ctx->{env};
+ return 1 if $env->{REQUEST_METHOD} eq 'POST';
+ my $referer = lc($env->{HTTP_REFERER} // '');
+ return 1 if $referer eq ''; # no referer is always OK for wget/curl
+
+ # prevent deep-linking from other domains on some browsers (Firefox)
+ # n.b.: $ctx->{ibx}->base_url($env) with INBOX_URL won't work
+ # with dillo, we can only match "$url_scheme://$HTTP_HOST/" without
+ # path components
+ my $base_url = lc($env->{'psgi.url_scheme'} . '://' .
+ ($env->{HTTP_HOST} //
+ "$env->{SERVER_NAME}:$env->{SERVER_PORT}") . '/');
+ index($referer, $base_url) == 0;
+}
+
sub get_attach_i { # ->each_part callback
my ($part, $depth, $idx) = @{$_[0]};
my $ctx = $_[1];
return if $idx ne $ctx->{idx}; # [0-9]+(?:\.[0-9]+)+
my $res = $ctx->{res};
$res->[0] = 200;
- my $ct = $part->content_type;
- $ct = parse_content_type($ct) if $ct;
-
+ my $ct = $part->ct;
if ($ct && (($ct->{type} || '') eq 'text')) {
# display all text as text/plain:
my $cset = $ct->{attributes}->{charset};
$ctx->{env});
$part = $ctx->zflush($part->body);
} else { # TODO: allow user to configure safe types
- $res->[1]->[1] = 'application/octet-stream';
- $part = $part->body;
+ if (referer_match($ctx)) {
+ $res->[1]->[1] = 'application/octet-stream';
+ $part = $part->body;
+ } else {
+ $res->[0] = 403;
+ $res->[1]->[1] = 'text/html';
+ $part = <<"";
+<html><head><title>download
+attachment</title><body><pre>Deep-linking prevented</pre><form
+method=post\naction=""><input type=submit value="Download attachment"
+/></form></body></html>
+
+ }
}
- push @{$res->[1]}, 'Content-Length', bytes::length($part);
+ push @{$res->[1]}, 'Content-Length', length($part);
$res->[2]->[0] = $part;
}
-sub async_eml { # ->{async_eml} for async_blob_cb
+sub async_eml { # for async_blob_cb
my ($ctx, $eml) = @_;
eval { $eml->each_part(\&get_attach_i, $ctx, 1) };
if ($@) {
sub scan_attach ($) { # public-inbox-httpd only
my ($ctx) = @_;
$ctx->{env}->{'psgix.io'}->{forward} = $ctx;
- $ctx->{async_eml} = \&async_eml;
- $ctx->{async_next} = \&async_next;
$ctx->smsg_blob($ctx->{smsg});
}
$ctx->{idx} = $idx;
bless $ctx, __PACKAGE__;
my $eml;
- if ($ctx->{smsg} = $ctx->{-inbox}->smsg_by_mid($ctx->{mid})) {
+ if ($ctx->{smsg} = $ctx->{ibx}->smsg_by_mid($ctx->{mid})) {
return sub { # public-inbox-httpd-only
$ctx->{wcb} = $_[0];
scan_attach($ctx);
} if $ctx->{env}->{'pi-httpd.async'};
# generic PSGI:
- $eml = $ctx->{-inbox}->smsg_eml($ctx->{smsg});
- } elsif (!$ctx->{-inbox}->over) {
- if (my $bref = $ctx->{-inbox}->msg_by_mid($ctx->{mid})) {
+ $eml = $ctx->{ibx}->smsg_eml($ctx->{smsg});
+ } elsif (!$ctx->{ibx}->over) {
+ if (my $bref = $ctx->{ibx}->msg_by_mid($ctx->{mid})) {
$eml = PublicInbox::Eml->new($bref);
}
}