3 files changed, 77 insertions, 2 deletions

diff --git a/.github/prepare_debian.sh b/.github/prepare_debian.sh
index d8a76da..5222659 100755
--- a/.github/prepare_debian.sh
+++ b/.github/prepare_debian.sh
@@ -5,6 +5,7 @@ set -e
 
 export DEBIAN_FRONTEND=noninteractive
 
+sed "s/main/non-free contrib/g" /etc/apt/sources.list.d/debian.sources > /etc/apt/sources.list.d/debian-nonfree.sources
 apt-get update
 apt-get -y install software-properties-common
 if [ $(lsb_release -is) = "Debian" ]; then
diff --git a/plugins/check_http.c b/plugins/check_http.c
index 5fa310f..8dda046 100644
--- a/plugins/check_http.c
+++ b/plugins/check_http.c
@@ -1462,7 +1462,13 @@ char *unchunk_content(const char *content) {
     memcpy(result + (overall_size - size_of_chunk), start_of_chunk, size_of_chunk);
   }
 
-  result[overall_size] = '\0';
+  if (overall_size == 0 && result == NULL) {
+    // We might just have received the end chunk without previous content, so result is never allocated
+    result = calloc(1, sizeof(char));
+    // No error handling here, we can only return NULL anyway
+  } else {
+    result[overall_size] = '\0';
+  }
   return result;
 }
 
diff --git a/plugins/tests/check_http.t b/plugins/tests/check_http.t
index d766ac3..6078b27 100755
--- a/plugins/tests/check_http.t
+++ b/plugins/tests/check_http.t
@@ -9,12 +9,14 @@ use strict;
 use Test::More;
 use NPTest;
 use FindBin qw($Bin);
+use IO::Socket::INET;
 
 $ENV{'LC_TIME'} = "C";
 
 my $common_tests = 71;
 my $virtual_port_tests = 8;
 my $ssl_only_tests = 12;
+my $chunked_encoding_special_tests = 1;
 # Check that all dependent modules are available
 eval "use HTTP::Daemon 6.01;";
 plan skip_all => 'HTTP::Daemon >= 6.01 required' if $@;
@@ -30,7 +32,7 @@ if ($@) {
         plan skip_all => "Missing required module for test: $@";
 } else {
         if (-x "./$plugin") {
-                plan tests => $common_tests * 2 + $ssl_only_tests + $virtual_port_tests;
+                plan tests => $common_tests * 2 + $ssl_only_tests + $virtual_port_tests + $chunked_encoding_special_tests;
         } else {
                 plan skip_all => "No $plugin compiled";
         }
@@ -51,6 +53,7 @@ my $port_http = 50000 + int(rand(1000));
 my $port_https = $port_http + 1;
 my $port_https_expired = $port_http + 2;
 my $port_https_clientcert = $port_http + 3;
+my $port_hacked_http = $port_http + 4;
 
 # This array keeps sockets around for implementing timeouts
 my @persist;
@@ -72,6 +75,28 @@ if (!$pid) {
 }
 push @pids, $pid;
 
+# Fork the hacked HTTP server
+undef $pid;
+$pid = fork;
+defined $pid or die "Failed to fork";
+if (!$pid) {
+        # this is the fork
+        undef @pids;
+        my $socket = new IO::Socket::INET (
+                LocalHost => '0.0.0.0',
+                LocalPort => $port_hacked_http,
+                Proto => 'tcp',
+                Listen => 5,
+                Reuse => 1
+        );
+        die "cannot create socket $!n" unless $socket;
+        my $local_sock = $socket->sockport();
+        print "server waiting for client connection on port $local_sock\n";
+        run_hacked_http_server ( $socket );
+        die "hacked http server stopped";
+}
+push @pids, $pid;
+
 if (exists $servers->{https}) {
         # Fork a normal HTTPS server
         $pid = fork;
@@ -207,6 +232,37 @@ sub run_server {
         }
 }
 
+sub run_hacked_http_server {
+        my $socket = shift;
+
+        # auto-flush on socket
+        $| = 1;
+
+
+        while(1)
+        {
+                # waiting for a new client connection
+                my $client_socket = $socket->accept();
+
+                # get information about a newly connected client
+                my $client_address = $client_socket->peerhost();
+                my $client_portn = $client_socket->peerport();
+                print "connection from $client_address:$client_portn";
+
+                # read up to 1024 characters from the connected client
+                my $data = "";
+                $client_socket->recv($data, 1024);
+                print "received data: $data";
+
+                # write response data to the connected client
+                $data = "HTTP/1.1 200 OK\r\nTransfer-Encoding: chunked\r\n\r\n0\r\n\r\n";
+                $client_socket->send($data);
+
+                # notify client that response has been sent
+                shutdown($client_socket, 1);
+        }
+}
+
 END {
         foreach my $pid (@pids) {
                 if ($pid) { print "Killing $pid\n"; kill "INT", $pid }
@@ -222,6 +278,7 @@ if ($ARGV[0] && $ARGV[0] eq "-d") {
 my $result;
 my $command = "./$plugin -H 127.0.0.1";
 
+run_chunked_encoding_special_test( {command => "$command -p $port_hacked_http"});
 run_common_tests( { command => "$command -p $port_http" } );
 SKIP: {
         skip "HTTP::Daemon::SSL not installed", $common_tests + $ssl_only_tests if ! exists $servers->{https};
@@ -511,3 +568,14 @@ sub run_common_tests {
         };
         is( $@, "", $cmd );
 }
+
+sub run_chunked_encoding_special_test {
+        my ($opts) = @_;
+        my $command = $opts->{command};
+
+        $cmd = "$command -u / -s 'ChunkedEncodingSpecialTest'";
+        eval {
+                $result = NPTest->testCmd( $cmd, 5 );
+        };
+        is( $@, "", $cmd );
+}