1 # Copyright (C) 2016-2019 all contributors <meta@public-inbox.org>
2 # License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
4 # Generic PSGI server for convenience. It aims to provide
5 # a consistent experience for public-inbox admins so they don't have
6 # to learn different ways to admin both NNTP and HTTP components.
7 # There's nothing which depends on public-inbox, here.
8 # Each instance of this class represents a HTTP client socket
10 package PublicInbox::HTTP;
13 use base qw(PublicInbox::DS);
14 use fields qw(httpd env input_left remote_addr remote_port forward);
15 use bytes (); # only for bytes::length
17 use Plack::HTTPParser qw(parse_http_request); # XS or pure Perl
18 use HTTP::Status qw(status_message);
19 use HTTP::Date qw(time2str);
21 use PublicInbox::DS qw(msg_more);
22 use PublicInbox::Syscall qw(EPOLLIN EPOLLONESHOT);
23 use PublicInbox::Tmpfile;
25 CHUNK_START => -1, # [a-f0-9]+\r\n
26 CHUNK_END => -2, # \r\n
27 CHUNK_ZEND => -3, # \r\n
33 sub process_pipelineq () {
37 next unless $_->{sock};
42 # Use the same configuration parameter as git since this is primarily
43 # a slow-client sponge for git-http-backend
44 # TODO: support per-respository http.maxRequestBuffer somehow...
45 our $MAX_REQUEST_BUFFER = $ENV{GIT_HTTP_MAX_REQUEST_BUFFER} ||
48 open(my $null_io, '<', '/dev/null') or die "failed to open /dev/null: $!";
53 $now == $prev ? $http_date : ($http_date = time2str($prev = $now));
57 my ($class, $sock, $addr, $httpd) = @_;
58 my $self = fields::new($class);
61 if (ref($sock) eq 'IO::Socket::SSL' && !$sock->accept_SSL) {
62 return CORE::close($sock) if $! != EAGAIN;
63 $ev = PublicInbox::TLS::epollbit();
64 $wbuf = [ \&PublicInbox::DS::accept_tls_step ];
66 $self->SUPER::new($sock, $ev | EPOLLONESHOT);
67 $self->{httpd} = $httpd;
68 $self->{wbuf} = $wbuf if $wbuf;
69 ($self->{remote_addr}, $self->{remote_port}) =
70 PublicInbox::Daemon::host_with_port($addr);
74 sub event_step { # called by PublicInbox::DS
77 return unless $self->flush_write && $self->{sock};
79 # only read more requests if we've drained the write buffer,
80 # otherwise we can be buffering infinitely w/o backpressure
82 return read_input($self) if defined $self->{env};
83 my $rbuf = $self->{rbuf} // (\(my $x = ''));
84 $self->do_read($rbuf, 8192, bytes::length($$rbuf)) or return;
85 rbuf_process($self, $rbuf);
89 my ($self, $rbuf) = @_;
90 $rbuf //= $self->{rbuf} // (\(my $x = ''));
92 my %env = %{$self->{httpd}->{env}}; # full hash copy
93 my $r = parse_http_request($$rbuf, \%env);
95 # We do not support Trailers in chunked requests, for now
96 # (they are rarely-used and git (as of 2.7.2) does not use them)
97 if ($r == -1 || $env{HTTP_TRAILER} ||
98 # this length-check is necessary for PURE_PERL=1:
99 ($r == -2 && bytes::length($$rbuf) > 0x4000)) {
100 return quit($self, 400);
102 if ($r < 0) { # incomplete
103 $self->rbuf_idle($rbuf);
104 return $self->requeue;
106 $$rbuf = substr($$rbuf, $r);
107 my $len = input_prepare($self, \%env);
108 defined $len or return write_err($self, undef); # EMFILE/ENFILE
110 $len ? read_input($self, $rbuf) : app_dispatch($self, undef, $rbuf);
113 # IO::Handle::write returns boolean, this returns bytes written:
115 my ($fh, $rbuf, $max) = @_;
116 my $w = bytes::length($$rbuf);
117 $w = $max if $w > $max;
118 $fh->write($$rbuf, $w) or return;
122 sub read_input ($;$) {
123 my ($self, $rbuf) = @_;
124 $rbuf //= $self->{rbuf} // (\(my $x = ''));
125 my $env = $self->{env};
126 return if $env->{REMOTE_ADDR}; # in app dispatch
127 return read_input_chunked($self, $rbuf) if env_chunked($env);
129 # env->{CONTENT_LENGTH} (identity)
130 my $len = delete $self->{input_left};
131 my $input = $env->{'psgi.input'};
135 my $w = xwrite($input, $rbuf, $len);
136 return write_err($self, $len) unless $w;
138 die "BUG: $len < 0 (w=$w)" if $len < 0;
139 if ($len == 0) { # next request may be pipelined
140 $$rbuf = substr($$rbuf, $w);
145 $self->do_read($rbuf, 8192) or return recv_err($self, $len);
146 # continue looping if $r > 0;
148 app_dispatch($self, $input, $rbuf);
152 my ($self, $input, $rbuf) = @_;
153 $self->rbuf_idle($rbuf);
154 my $env = $self->{env};
155 $env->{REMOTE_ADDR} = $self->{remote_addr};
156 $env->{REMOTE_PORT} = $self->{remote_port};
157 if (my $host = $env->{HTTP_HOST}) {
158 $host =~ s/:([0-9]+)\z// and $env->{SERVER_PORT} = $1;
159 $env->{SERVER_NAME} = $host;
161 if (defined $input) {
162 sysseek($input, 0, SEEK_SET) or
163 die "BUG: psgi.input seek failed: $!";
165 # note: NOT $self->{sock}, we want our close (+ PublicInbox::DS::close),
166 # to do proper cleanup:
167 $env->{'psgix.io'} = $self; # only for ->close
168 my $res = Plack::Util::run_app($self->{httpd}->{app}, $env);
170 if (ref($res) eq 'CODE') {
171 $res->(sub { response_write($self, $env, $_[0]) });
173 response_write($self, $env, $res);
179 sub response_header_write {
180 my ($self, $env, $res) = @_;
181 my $proto = $env->{SERVER_PROTOCOL} or return; # HTTP/0.9 :P
182 my $status = $res->[0];
183 my $h = "$proto $status " . status_message($status) . "\r\n";
185 my $headers = $res->[1];
187 for (my $i = 0; $i < @$headers; $i += 2) {
188 my $k = $headers->[$i];
189 my $v = $headers->[$i + 1];
190 next if $k =~ /\A(?:Connection|Date)\z/i;
192 $len = $v if $k =~ /\AContent-Length\z/i;
193 if ($k =~ /\ATransfer-Encoding\z/i && $v =~ /\bchunked\b/i) {
199 my $conn = $env->{HTTP_CONNECTION} || '';
200 my $term = defined($len) || $chunked;
201 my $prot_persist = ($proto eq 'HTTP/1.1') && ($conn !~ /\bclose\b/i);
203 if (!$term && $prot_persist) { # auto-chunk
204 $chunked = $alive = 2;
205 $h .= "Transfer-Encoding: chunked\r\n";
206 # no need for "Connection: keep-alive" with HTTP/1.1
207 } elsif ($term && ($prot_persist || ($conn =~ /\bkeep-alive\b/i))) {
209 $h .= "Connection: keep-alive\r\n";
212 $h .= "Connection: close\r\n";
214 $h .= 'Date: ' . http_date() . "\r\n\r\n";
216 if (($len || $chunked) && $env->{REQUEST_METHOD} ne 'HEAD') {
224 # middlewares such as Deflater may write empty strings
225 sub chunked_wcb ($) {
228 return if $_[0] eq '';
229 msg_more($self, sprintf("%x\r\n", bytes::length($_[0])));
230 msg_more($self, $_[0]);
232 # use $self->write(\"\n\n") if you care about real-time
233 # streaming responses, public-inbox WWW does not.
234 msg_more($self, "\r\n");
238 sub identity_wcb ($) {
240 sub { $self->write(\($_[0])) if $_[0] ne '' }
243 sub next_request ($) {
246 # avoid recursion for pipelined requests
247 PublicInbox::DS::requeue(\&process_pipelineq) if !@$pipelineq;
248 push @$pipelineq, $self;
249 } else { # wait for next request
254 sub response_done_cb ($$) {
255 my ($self, $alive) = @_;
257 delete $self->{env}; # we're no longer busy
258 $self->write(\"0\r\n\r\n") if $alive == 2;
259 $self->write($alive ? \&next_request : \&close);
263 sub getline_response ($$$) {
264 my ($self, $write, $close) = @_;
265 my $pull; # DANGER: self-referential
267 my $forward = $self->{forward};
268 # limit our own running time for fairness with other
269 # clients and to avoid buffering too much:
276 $write->($buf); # may close in PublicInbox::DS::write
279 my $wbuf = $self->{wbuf} ||= [];
282 # wbuf may be populated by $write->($buf),
283 # no need to rearm if so:
284 $self->requeue if scalar(@$wbuf) == 1;
288 err($self, "response ->getline error: $@");
292 $pull = undef; # all done!
294 if (delete $self->{forward}) {
295 eval { $forward->close };
297 err($self, "response ->close error: $@");
298 $self->close; # idempotent
302 $close->(); # call response_done_cb
305 $pull->(); # kick-off!
309 my ($self, $env, $res) = @_;
310 my $alive = response_header_write($self, $env, $res);
311 my $close = response_done_cb($self, $alive);
312 my $write = $alive == 2 ? chunked_wcb($self) : identity_wcb($self);
313 if (defined(my $body = $res->[2])) {
314 if (ref $body eq 'ARRAY') {
315 $write->($_) foreach @$body;
318 $self->{forward} = $body;
319 getline_response($self, $write, $close);
322 # this is returned to the calling application:
323 Plack::Util::inline_object(write => $write, close => $close);
327 sub input_tmpfile ($) {
328 my $input = tmpfile('http.input', $_[0]->{sock}) or return;
329 $input->autoflush(1);
334 my ($self, $env) = @_;
336 my $len = $env->{CONTENT_LENGTH};
338 if ($len > $MAX_REQUEST_BUFFER) {
342 $input = input_tmpfile($self);
343 } elsif (env_chunked($env)) {
345 $input = input_tmpfile($self);
350 # TODO: expire idle clients on ENFILE / EMFILE
351 return unless $input;
353 $env->{'psgi.input'} = $input;
355 $self->{input_left} = $len || 0;
358 sub env_chunked { ($_[0]->{HTTP_TRANSFER_ENCODING} || '') =~ /\bchunked\b/i }
361 eval { $_[0]->{httpd}->{env}->{'psgi.errors'}->print($_[1]."\n") };
365 my ($self, $len) = @_;
366 my $msg = $! || '(zero write)';
367 $msg .= " ($len bytes remaining)" if defined $len;
368 err($self, "error buffering to input: $msg");
373 my ($self, $len) = @_;
374 if ($! == EAGAIN) { # epoll/kevent watch already set by do_read
375 $self->{input_left} = $len;
377 err($self, "error reading input: $! ($len bytes remaining)");
381 sub read_input_chunked { # unlikely...
382 my ($self, $rbuf) = @_;
383 $rbuf //= $self->{rbuf} // (\(my $x = ''));
384 my $input = $self->{env}->{'psgi.input'};
385 my $len = delete $self->{input_left};
387 while (1) { # chunk start
388 if ($len == CHUNK_ZEND) {
389 $$rbuf =~ s/\A\r\n//s and
390 return app_dispatch($self, $input, $rbuf);
392 return quit($self, 400) if bytes::length($$rbuf) > 2;
394 if ($len == CHUNK_END) {
395 if ($$rbuf =~ s/\A\r\n//s) {
397 } elsif (bytes::length($$rbuf) > 2) {
398 return quit($self, 400);
401 if ($len == CHUNK_START) {
402 if ($$rbuf =~ s/\A([a-f0-9]+).*?\r\n//i) {
404 if (($len + -s $input) > $MAX_REQUEST_BUFFER) {
405 return quit($self, 413);
407 } elsif (bytes::length($$rbuf) > CHUNK_MAX_HDR) {
408 return quit($self, 400);
410 # will break from loop since $len >= 0
413 if ($len < 0) { # chunk header is trickled, read more
414 $self->do_read($rbuf, 8192, bytes::length($$rbuf)) or
415 return recv_err($self, $len);
416 # (implicit) goto chunk_start if $r > 0;
418 $len = CHUNK_ZEND if $len == 0;
420 # drain the current chunk
423 my $w = xwrite($input, $rbuf, $len);
424 return write_err($self, "$len chunk") if !$w;
427 # we may have leftover data to parse
429 $$rbuf = substr($$rbuf, $w);
432 die "BUG: len < 0: $len";
438 # read more of current chunk
439 $self->do_read($rbuf, 8192) or
440 return recv_err($self, $len);
447 my ($self, $status) = @_;
448 my $h = "HTTP/1.1 $status " . status_message($status) . "\r\n\r\n";
455 delete $self->{env}; # prevent circular references
456 if (my $forward = delete $self->{forward}) {
457 eval { $forward->close };
458 err($self, "forward ->close error: $@") if $@;
460 $self->SUPER::close; # PublicInbox::DS::close
463 # for graceful shutdown in PublicInbox::Daemon:
466 ($self->{rbuf} || $self->{env} || $self->{wbuf});