http: fix RFC conformance w.r.t. message length

[public-inbox.git] / lib / PublicInbox / HTTP.pm

diff --git a/lib/PublicInbox/HTTP.pm b/lib/PublicInbox/HTTP.pm
index df328904a86b57e318879afa67da71ecea35ee8f..b73ce2d733500f9f38a540806200183301d99079 100644 (file)
--- a/lib/PublicInbox/HTTP.pm
+++ b/lib/PublicInbox/HTTP.pm
@@ -335,19 +335,31 @@ sub input_tmpfile ($) {
 
 sub input_prepare {
        my ($self, $env) = @_;
-       my $input;
-       my $len = $env->{CONTENT_LENGTH};
-       if ($len) {
-               if ($len > $MAX_REQUEST_BUFFER) {
-                       quit($self, 413);
-                       return;
-               }
-               $input = input_tmpfile($self);
-       } elsif (env_chunked($env)) {
+       my ($input, $len);
+
+       # rfc 7230 3.3.2, 3.3.3,: favor Transfer-Encoding over Content-Length
+       my $hte = $env->{HTTP_TRANSFER_ENCODING};
+       if (defined $hte) {
+               # rfc7230 3.3.3, point 3 says only chunked is accepted
+               # as the final encoding.  Since neither public-inbox-httpd,
+               # git-http-backend, or our WWW-related code uses "gzip",
+               # "deflate" or "compress" as the Transfer-Encoding, we'll
+               # reject them:
+               return quit($self, 400) if $hte !~ /\Achunked\z/i;
+
                $len = CHUNK_START;
                $input = input_tmpfile($self);
        } else {
-               $input = $null_io;
+               $len = $env->{CONTENT_LENGTH};
+               if (defined $len) {
+                       # rfc7230 3.3.3.4
+                       return quit($self, 400) if $len !~ /\A[0-9]+\z/;
+
+                       return quit($self, 413) if $len > $MAX_REQUEST_BUFFER;
+                       $input = $len ? input_tmpfile($self) : $null_io;
+               } else {
+                       $input = $null_io;
+               }
        }
 
        # TODO: expire idle clients on ENFILE / EMFILE
@@ -358,7 +370,7 @@ sub input_prepare {
        $self->{input_left} = $len || 0;
 }
 
-sub env_chunked { ($_[0]->{HTTP_TRANSFER_ENCODING} || '') =~ /\bchunked\b/i }
+sub env_chunked { ($_[0]->{HTTP_TRANSFER_ENCODING} // '') =~ /\Achunked\z/i }
 
 sub err ($$) {
        eval { $_[0]->{httpd}->{env}->{'psgi.errors'}->print($_[1]."\n") };
@@ -451,6 +463,7 @@ sub quit {
        my $h = "HTTP/1.1 $status " . status_message($status) . "\r\n\r\n";
        $self->write(\$h);
        $self->close;
+       undef; # input_prepare expects this
 }
 
 sub close {