[core] add strict.post_content_length option

Change-Id: Ie9d67eceed7e957b667554925d562018a3217209

doc/plugin_core.xml

@@ -100,6 +100,15 @@
 				</textile>
 			</description>
 		</option>
+		<option name="strict.post_content_length">
+			<short>require Content-Length for POST requests</short>
+			<default><value>true</value></default>
+			<description>
+				<textile>
+					Some clients don't send Content-Length for POST requests with empty body; they should send @Content-Length: 0@.  When this check is enabled they'll get a @411 Length required@ error.
+				</textile>
+			</description>
+		</option>
 
 		<option name="static.exclude_extensions">
 			<short>don't deliver static files with one of the listed extensions</short>

include/lighttpd/plugin_core.h

@@ -17,7 +17,9 @@ enum liCoreOptions {
 
 	LI_CORE_OPTION_ASYNC_STAT,
 
-	LI_CORE_OPTION_BUFFER_ON_DISK_REQUEST_BODY
+	LI_CORE_OPTION_BUFFER_ON_DISK_REQUEST_BODY,
+
+	LI_CORE_OPTION_STRICT_POST_CONTENT_LENGTH,
 };
 
 enum liCoreOptionPtrs {

src/main/plugin_core.c

@@ -2079,6 +2079,8 @@ static const liPluginOption options[] = {
 
 	{ "buffer_request_body", LI_VALUE_BOOLEAN, TRUE, NULL },
 
+	{ "strict.post_content_length", LI_VALUE_BOOLEAN, TRUE, NULL },
+
 	{ NULL, 0, 0, NULL }
 };
 

src/main/request.c

@@ -1,5 +1,6 @@
 
 #include <lighttpd/base.h>
+#include <lighttpd/plugin_core.h>
 #include <lighttpd/url_parser.h>
 
 void li_request_init(liRequest *req) {
@@ -292,10 +293,14 @@ gboolean li_request_validate_header(liConnection *con) {
 		/* content-length or chunked encoding is required for them */
 		if (con->mainvr->request.content_length == -1 && !transfer_encoding_chunked) {
 			/* content-length is missing */
-			VR_ERROR(con->mainvr, "%s", "POST-request, but content-length missing -> 411");
+			if (_CORE_OPTION(con->mainvr, LI_CORE_OPTION_STRICT_POST_CONTENT_LENGTH).boolean) {
+				VR_ERROR(con->mainvr, "%s", "POST-request, but content-length missing -> 411");
 
-			bad_request(con, 411); /* Length Required */
-			return FALSE;
+				bad_request(con, 411); /* Length Required */
+				return FALSE;
+			} else {
+				con->mainvr->request.content_length = 0;
+			}
 		}
 		break;
 	default: