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 alive);
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_write ($$) {
227 return if $_[1] eq '';
228 msg_more($self, sprintf("%x\r\n", bytes::length($_[1])));
229 msg_more($self, $_[1]);
231 # use $self->write(\"\n\n") if you care about real-time
232 # streaming responses, public-inbox WWW does not.
233 msg_more($self, "\r\n");
236 sub identity_write ($$) {
238 $self->write(\($_[1])) if $_[1] ne '';
241 sub next_request ($) {
244 # avoid recursion for pipelined requests
245 PublicInbox::DS::requeue(\&process_pipelineq) if !@$pipelineq;
246 push @$pipelineq, $self;
247 } else { # wait for next request
253 my ($self, $alive) = @_;
254 delete $self->{env}; # we're no longer busy
255 $self->write(\"0\r\n\r\n") if $alive == 2;
256 $self->write($alive ? \&next_request : \&close);
261 my $forward = $self->{forward};
263 # limit our own running time for fairness with other
264 # clients and to avoid buffering too much:
271 # may close in PublicInbox::DS::write
272 if ($self->{alive} == 2) {
273 chunked_write($self, $buf);
275 identity_write($self, $buf);
279 my $wbuf = $self->{wbuf} //= [];
280 push @$wbuf, \&getline_pull;
282 # wbuf may be populated by {chunked,identity}_write()
283 # above, no need to rearm if so:
284 $self->requeue if scalar(@$wbuf) == 1;
288 err($self, "response ->getline error: $@");
292 if (delete $self->{forward}) {
293 eval { $forward->close };
295 err($self, "response ->close error: $@");
296 $self->close; # idempotent
299 response_done($self, delete $self->{alive});
303 my ($self, $env, $res) = @_;
304 my $alive = response_header_write($self, $env, $res);
305 if (defined(my $body = $res->[2])) {
306 if (ref $body eq 'ARRAY') {
308 chunked_write($self, $_) for @$body;
310 identity_write($self, $_) for @$body;
312 response_done($self, $alive);
314 $self->{forward} = $body;
315 $self->{alive} = $alive;
316 getline_pull($self); # kick-off!
318 # these are returned to the calling application:
319 } elsif ($alive == 2) {
320 bless [ $self, $alive ], 'PublicInbox::HTTP::Chunked';
322 bless [ $self, $alive ], 'PublicInbox::HTTP::Identity';
326 sub input_tmpfile ($) {
327 my $input = tmpfile('http.input', $_[0]->{sock}) or return;
328 $input->autoflush(1);
333 my ($self, $env) = @_;
335 my $len = $env->{CONTENT_LENGTH};
337 if ($len > $MAX_REQUEST_BUFFER) {
341 $input = input_tmpfile($self);
342 } elsif (env_chunked($env)) {
344 $input = input_tmpfile($self);
349 # TODO: expire idle clients on ENFILE / EMFILE
350 return unless $input;
352 $env->{'psgi.input'} = $input;
354 $self->{input_left} = $len || 0;
357 sub env_chunked { ($_[0]->{HTTP_TRANSFER_ENCODING} || '') =~ /\bchunked\b/i }
360 eval { $_[0]->{httpd}->{env}->{'psgi.errors'}->print($_[1]."\n") };
364 my ($self, $len) = @_;
365 my $msg = $! || '(zero write)';
366 $msg .= " ($len bytes remaining)" if defined $len;
367 err($self, "error buffering to input: $msg");
372 my ($self, $len) = @_;
373 if ($! == EAGAIN) { # epoll/kevent watch already set by do_read
374 $self->{input_left} = $len;
376 err($self, "error reading input: $! ($len bytes remaining)");
380 sub read_input_chunked { # unlikely...
381 my ($self, $rbuf) = @_;
382 $rbuf //= $self->{rbuf} // (\(my $x = ''));
383 my $input = $self->{env}->{'psgi.input'};
384 my $len = delete $self->{input_left};
386 while (1) { # chunk start
387 if ($len == CHUNK_ZEND) {
388 $$rbuf =~ s/\A\r\n//s and
389 return app_dispatch($self, $input, $rbuf);
391 return quit($self, 400) if bytes::length($$rbuf) > 2;
393 if ($len == CHUNK_END) {
394 if ($$rbuf =~ s/\A\r\n//s) {
396 } elsif (bytes::length($$rbuf) > 2) {
397 return quit($self, 400);
400 if ($len == CHUNK_START) {
401 if ($$rbuf =~ s/\A([a-f0-9]+).*?\r\n//i) {
403 if (($len + -s $input) > $MAX_REQUEST_BUFFER) {
404 return quit($self, 413);
406 } elsif (bytes::length($$rbuf) > CHUNK_MAX_HDR) {
407 return quit($self, 400);
409 # will break from loop since $len >= 0
412 if ($len < 0) { # chunk header is trickled, read more
413 $self->do_read($rbuf, 8192, bytes::length($$rbuf)) or
414 return recv_err($self, $len);
415 # (implicit) goto chunk_start if $r > 0;
417 $len = CHUNK_ZEND if $len == 0;
419 # drain the current chunk
422 my $w = xwrite($input, $rbuf, $len);
423 return write_err($self, "$len chunk") if !$w;
426 # we may have leftover data to parse
428 $$rbuf = substr($$rbuf, $w);
431 die "BUG: len < 0: $len";
437 # read more of current chunk
438 $self->do_read($rbuf, 8192) or
439 return recv_err($self, $len);
446 my ($self, $status) = @_;
447 my $h = "HTTP/1.1 $status " . status_message($status) . "\r\n\r\n";
454 delete $self->{env}; # prevent circular references
455 if (my $forward = delete $self->{forward}) {
456 eval { $forward->close };
457 err($self, "forward ->close error: $@") if $@;
459 $self->SUPER::close; # PublicInbox::DS::close
462 # for graceful shutdown in PublicInbox::Daemon:
465 ($self->{rbuf} || $self->{env} || $self->{wbuf});
468 # Chunked and Identity packages are used for writing responses.
469 # They may be exposed to the PSGI application when the PSGI app
470 # returns a CODE ref for "push"-based responses
471 package PublicInbox::HTTP::Chunked;
475 # ([$http], $buf) = @_;
476 PublicInbox::HTTP::chunked_write($_[0]->[0], $_[1])
480 # $_[0] = [$http, $alive]
481 PublicInbox::HTTP::response_done(@{$_[0]});
484 package PublicInbox::HTTP::Identity;
486 our @ISA = qw(PublicInbox::HTTP::Chunked);
489 # ([$http], $buf) = @_;
490 PublicInbox::HTTP::identity_write($_[0]->[0], $_[1]);