MINOR: htx: unconditionally handle parsing errors in requests or responses

The htx request and response processing functions currently only check
for HTX_FL_PARSING_ERROR on incomplete messages because that's how mux_h1
delivers these. However with H2 we have to detect some parsing errors in
the format of certain pseudo-headers (e.g. :path), so we do have a complete
message but we want to report an error.

Let's move the parse error check earlier so that it always triggers when
the flag is present. It was also moved for htx_wait_for_request_body()
since we definitely want to be able to abort processing such an invalid
request even if it appears complete, but it was not changed in the forward
functions so as not to truncate contents before the position of the first
error.

diff --git a/src/proto_htx.c b/src/proto_htx.c
index 2f100886f05ee9e2470252ca63bf7a5edd7573c6..9009fa9be7acf382dd7e3ed93088f3ec54822528 100644 (file)
--- a/src/proto_htx.c
+++ b/src/proto_htx.c
@@ -97,6 +97,14 @@ int htx_wait_for_request(struct stream *s, struct channel *req, int an_bit)
 
        htx = htxbuf(&req->buf);
 
+       /* Parsing errors are caught here */
+       if (htx->flags & HTX_FL_PARSING_ERROR) {
+               stream_inc_http_req_ctr(s);
+               stream_inc_http_err_ctr(s);
+               proxy_inc_fe_req_ctr(sess->fe);
+               goto return_bad_req;
+       }
+
        /* we're speaking HTTP here, so let's speak HTTP to the client */
        s->srv_error = http_return_srv_error;
 
@@ -126,12 +134,11 @@ int htx_wait_for_request(struct stream *s, struct channel *req, int an_bit)
         */
        if (unlikely(htx_is_empty(htx) || htx_get_tail_type(htx) < HTX_BLK_EOH)) {
                /*
-                * First catch invalid request because of a parsing error or
-                * because only part of headers have been transfered.
-                * Multiplexers have the responsibility to emit all headers at
-                * once.
+                * First catch invalid request because only part of headers have
+                * been transfered. Multiplexers have the responsibility to emit
+                * all headers at once.
                 */
-               if ((htx->flags & HTX_FL_PARSING_ERROR) || htx_is_not_empty(htx) || (s->si[0].flags & SI_FL_RXBLK_ROOM)) {
+               if (htx_is_not_empty(htx) || (s->si[0].flags & SI_FL_RXBLK_ROOM)) {
                        stream_inc_http_req_ctr(s);
                        stream_inc_http_err_ctr(s);
                        proxy_inc_fe_req_ctr(sess->fe);
@@ -1055,6 +1062,9 @@ int htx_wait_for_request_body(struct stream *s, struct channel *req, int an_bit)
 
        htx = htxbuf(&req->buf);
 
+       if (htx->flags & HTX_FL_PARSING_ERROR)
+               goto return_bad_req;
+
        if (msg->msg_state < HTTP_MSG_BODY)
                goto missing_data;
 
@@ -1093,9 +1103,6 @@ int htx_wait_for_request_body(struct stream *s, struct channel *req, int an_bit)
                goto http_end;
 
  missing_data:
-       if (htx->flags & HTX_FL_PARSING_ERROR)
-               goto return_bad_req;
-
        if ((req->flags & CF_READ_TIMEOUT) || tick_is_expired(req->analyse_exp, now_ms)) {
                txn->status = 408;
                htx_reply_and_close(s, txn->status, htx_error_message(s));
@@ -1446,6 +1453,10 @@ int htx_wait_for_response(struct stream *s, struct channel *rep, int an_bit)
 
        htx = htxbuf(&rep->buf);
 
+       /* Parsing errors are caught here */
+       if (htx->flags & HTX_FL_PARSING_ERROR)
+               goto return_bad_res;
+
        /*
         * Now we quickly check if we have found a full valid response.
         * If not so, we check the FD and buffer states before leaving.
@@ -1466,8 +1477,7 @@ int htx_wait_for_response(struct stream *s, struct channel *rep, int an_bit)
                 * once. We must be sure to have forwarded all outgoing data
                 * first.
                 */
-               if (!co_data(rep) &&
-                   ((htx->flags & HTX_FL_PARSING_ERROR) || htx_is_not_empty(htx) || (s->si[1].flags & SI_FL_RXBLK_ROOM)))
+               if (!co_data(rep) && (htx_is_not_empty(htx) || (s->si[1].flags & SI_FL_RXBLK_ROOM)))
                        goto return_bad_res;
 
                /* 1: have we encountered a read error ? */