-# Copyright (C) 2015 all contributors <meta@public-inbox.org>
-# License: AGPLv3 or later (https://www.gnu.org/licenses/agpl-3.0.txt)
+# Copyright (C) 2015-2021 all contributors <meta@public-inbox.org>
+# License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
+#
+# Various Message-ID-related functions.
package PublicInbox::MID;
use strict;
use warnings;
use base qw/Exporter/;
-our @EXPORT_OK = qw/mid_clean mid_compress mid2path/;
+our @EXPORT_OK = qw(mid_clean id_compress mid2path mid_escape MID_ESC
+ mids references mids_for_index mids_in $MID_EXTRACT);
+use URI::Escape qw(uri_escape_utf8);
use Digest::SHA qw/sha1_hex/;
-use constant MID_MAX => 40; # SHA-1 hex length
+require PublicInbox::Address;
+use constant {
+ ID_MAX => 40, # SHA-1 hex length for HTML id anchors
+ MAX_MID_SIZE => 244, # max term size (Xapian limitation) - length('Q')
+};
+
+our $MID_EXTRACT = qr/<([^>]+)>/s;
sub mid_clean {
my ($mid) = @_;
defined($mid) or die "no Message-ID";
# MDA->precheck did more checking for us
- if ($mid =~ /<([^>]+)>/) {
+ if ($mid =~ $MID_EXTRACT) {
$mid = $1;
}
$mid;
}
-# this is idempotent
-sub mid_compress {
- my ($mid, $force) = @_;
-
- # XXX dirty hack! FIXME!
- # Some HTTP servers (apache2 2.2.22-13+deb7u5 on my system)
- # apparently do not handle "%25" in the URL path component correctly.
- # I'm not yet sure if it's something weird with my rewrite rules
- # or what; will need to debug...
- return sha1_hex($mid) if (index($mid, '%') >= 0);
+# this is idempotent, used for HTML anchor/ids and such
+sub id_compress {
+ my ($id, $force) = @_;
- return $mid if (!$force && length($mid) <= MID_MAX);
- sha1_hex($mid);
+ if ($force || $id =~ /[^a-zA-Z0-9_\-]/ || length($id) > ID_MAX) {
+ utf8::encode($id);
+ return sha1_hex($id);
+ }
+ $id;
}
sub mid2path {
unless (defined $x38) {
# compatibility with old links (or short Message-IDs :)
- $mid = sha1_hex(mid_clean($mid));
+ $mid = mid_clean($mid);
+ utf8::encode($mid);
+ $mid = sha1_hex($mid);
($x2, $x38) = ($mid =~ /\A([a-f0-9]{2})([a-f0-9]{38})\z/);
}
"$x2/$x38";
}
+# only intended for Message-ID and X-Alt-Message-ID
+sub extract_mids {
+ my @mids;
+ for my $v (@_) {
+ my @cur = ($v =~ /$MID_EXTRACT/g);
+ if (@cur) {
+ push(@mids, @cur);
+ } else {
+ push(@mids, $v);
+ }
+ }
+ \@mids;
+}
+
+sub mids ($) {
+ my ($hdr) = @_;
+ my @mids = $hdr->header_raw('Message-ID');
+ uniq_mids(extract_mids(@mids));
+}
+
+# for Resent-Message-ID and maybe others
+sub mids_in ($@) {
+ my ($eml, @headers) = @_;
+ uniq_mids(extract_mids(map { ($eml->header_raw($_)) } @headers));
+}
+
+# we allow searching on X-Alt-Message-ID since PublicInbox::NNTP uses them
+# to placate some clients, and we want to ensure NNTP-only clients can
+# import and index without relying on HTTP endpoints
+sub mids_for_index ($) {
+ mids_in($_[0], qw(Message-ID X-Alt-Message-ID));
+}
+
+# last References should be IRT, but some mail clients do things
+# out of order, so trust IRT over References iff IRT exists
+sub references ($) {
+ my ($hdr) = @_;
+ my @mids;
+ foreach my $f (qw(References In-Reply-To)) {
+ my @v = $hdr->header_raw($f);
+ foreach my $v (@v) {
+ push(@mids, ($v =~ /$MID_EXTRACT/g));
+ }
+ }
+
+ # old versions of git-send-email would prompt users for
+ # In-Reply-To and users' muscle memory would use 'y' or 'n'
+ # as responses:
+ my %addr = ( y => 1, n => 1 );
+
+ foreach my $f (qw(To From Cc)) {
+ my @v = $hdr->header_raw($f);
+ foreach my $v (@v) {
+ $addr{$_} = 1 for (PublicInbox::Address::emails($v));
+ }
+ }
+ uniq_mids(\@mids, \%addr);
+}
+
+sub uniq_mids ($;$) {
+ my ($mids, $seen) = @_;
+ my @ret;
+ $seen ||= {};
+ foreach my $mid (@$mids) {
+ $mid =~ tr/\n\t\r//d;
+ if (length($mid) > MAX_MID_SIZE) {
+ warn "Message-ID: <$mid> too long, truncating\n";
+ $mid = substr($mid, 0, MAX_MID_SIZE);
+ }
+ $seen->{$mid} //= push(@ret, $mid);
+ }
+ \@ret;
+}
+
+# RFC3986, section 3.3:
+sub MID_ESC () { '^A-Za-z0-9\-\._~!\$\&\'\(\)\*\+,;=:@' }
+sub mid_escape ($) { uri_escape_utf8($_[0], MID_ESC) }
+
1;