1 # Copyright (C) 2016-2021 all contributors <meta@public-inbox.org>
2 # License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
4 # Standalone PSGI app to handle HTTP(s) unsubscribe links generated
5 # by milters like examples/unsubscribe.milter to mailing lists.
7 # This does not depend on any other modules in the PublicInbox::*
8 # and ought to be usable with any mailing list software.
9 package PublicInbox::Unsubscribe;
14 use MIME::Base64 qw(decode_base64url);
15 my @CODE_URL = qw(http://7fh6tueqddpjyxjmgtdiueylzoqt6pt7hec3pukyptlmohoowvhde4yd.onion/public-inbox.git
16 https://public-inbox.org/public-inbox.git);
17 my @CT_HTML = ('Content-Type', 'text/html; charset=UTF-8');
20 my ($class, %opt) = @_;
21 my $key_file = $opt{key_file};
22 defined $key_file or die "`key_file' needed";
23 open my $fh, '<', $key_file or die
24 "failed to open key_file=$key_file: $!\n";
26 if (read($fh, $key, 8) != 8 || read($fh, $iv, 8) != 8 ||
27 read($fh, my $end, 8) != 0) {
28 die "key_file must be 16 bytes\n";
31 # these parameters were chosen to generate shorter parameters
32 # to reduce the possibility of copy+paste errors
33 my $cipher = Crypt::CBC->new(-key => $key,
36 -cipher => 'Blowfish');
38 my $e = $opt{owner_email} or die "`owner_email' not specified\n";
39 my $unsubscribe = $opt{unsubscribe} or
40 die "`unsubscribe' callback not given\n";
42 my $code_url = $opt{code_url} || \@CODE_URL;
43 $code_url = [ $code_url ] if ref($code_url) ne 'ARRAY';
45 pi_cfg => $opt{pi_config}, # PublicInbox::Config
46 owner_email => $opt{owner_email},
48 unsubscribe => $unsubscribe,
49 contact => qq(<a\nhref="mailto:$e">$e</a>),
50 code_url => $code_url,
51 confirm => $opt{confirm},
55 # entry point for PSGI
57 my ($self, $env) = @_;
58 my $m = $env->{REQUEST_METHOD};
59 if ($m eq 'GET' || $m eq 'HEAD') {
60 $self->{confirm} ? confirm_prompt($self, $env)
61 : finalize_unsub($self, $env);
62 } elsif ($m eq 'POST') {
63 finalize_unsub($self, $env);
66 Plack::Util::encode_html($m).' method not allowed');
71 my ($self, $env) = @_;
72 my ($blank, $u, $list) = split('/', $env->{PATH_INFO});
74 if (!defined $u || $u eq '') {
75 return r($self, 400, 'Bad request',
76 'Missing encrypted email address in path component');
78 if (!defined $list && $list eq '') {
79 return r($self, 400, 'Bad request',
80 'Missing mailing list name in path component');
82 my $user = eval { $self->{cipher}->decrypt(decode_base64url($u)) };
83 if (!defined $user || index($user, '@') < 1) {
84 my $err = quotemeta($@);
85 my $errors = $env->{'psgi.errors'};
86 $errors->print("error decrypting: $u\n");
87 $errors->print("$_\n") for split("\n", $err);
88 $u = Plack::Util::encode_html($u);
89 return r($self, 400, 'Bad request', "Failed to decrypt: $u");
92 # The URLs are too damn long if we have the encrypted domain
93 # name in the PATH_INFO
94 if (index($list, '@') < 0) {
95 my $host = (split(':', $env->{HTTP_HOST}))[0];
101 sub confirm_prompt { # on GET
102 my ($self, $env) = @_;
103 my ($user_addr, $list_addr) = _user_list_addr($self, $env);
104 return $user_addr if ref $user_addr;
106 my $xl = Plack::Util::encode_html($list_addr);
107 my $xu = Plack::Util::encode_html($user_addr);
109 "Confirmation required to remove", '',
111 "from the mailing list at", '',
113 'You will get one last email once you hit "Confirm" below:',
114 qq(</pre><form\nmethod=post\naction="">) .
115 qq(<input\ntype=submit\nvalue="Confirm" />) .
118 push @body, archive_info($self, $env, $list_addr);
120 r($self, 200, "Confirm unsubscribe for $xl", @body);
123 sub finalize_unsub { # on POST
124 my ($self, $env) = @_;
125 my ($user_addr, $list_addr) = _user_list_addr($self, $env);
126 return $user_addr if ref $user_addr;
128 my @archive = archive_info($self, $env, $list_addr);
129 if (my $err = $self->{unsubscribe}->($user_addr, $list_addr)) {
130 return r($self, 500, Plack::Util::encode_html($err), @archive);
133 my $xl = Plack::Util::encode_html($list_addr);
134 r($self, 200, "Unsubscribed from $xl",
135 'You may get one final goodbye message', @archive);
139 my ($self, $code, $title, @body) = @_;
140 [ $code, [ @CT_HTML ], [
141 "<html><head><title>$title</title></head><body><pre>".
142 join("\n", "<b>$title</b>\n", @body) . '</pre><hr>'.
143 "<pre>This page is available under AGPL-3.0+\n" .
144 join('', map { "git clone $_\n" } @{$self->{code_url}}) .
145 qq(Email $self->{contact} if you have any questions).
146 '</pre></body></html>'
151 my ($self, $env, $list_addr) = @_;
152 my $archive_url = $self->{archive_urls}->{$list_addr};
154 unless ($archive_url) {
155 if (my $cfg = $self->{pi_cfg}) {
156 # PublicInbox::Config::lookup
157 my $ibx = $cfg->lookup($list_addr);
158 # PublicInbox::Inbox::base_url
159 $archive_url = $ibx->base_url if $ibx;
163 # protocol-relative URL: "//example.com/" => "https://example.com/"
164 if ($archive_url && $archive_url =~ m!\A//!) {
165 $archive_url = "$env->{'psgi.url_scheme'}:$archive_url";
168 # maybe there are other places where we could map
169 # list_addr => archive_url without ~/.public-inbox/config
171 $archive_url = Plack::Util::encode_html($archive_url);
173 'HTML and git clone-able archives are available at:',
174 qq(<a\nhref="$archive_url">$archive_url</a>))
177 'There ought to be archives for this list,',
178 'but unfortunately the admin did not configure '.
179 __PACKAGE__. ' to show you the URL');