BUG/MEDIUM: mux-h1: Don't add "transfer-encoding" if message-body is forbidden
When a HTTP/1.1 or above response is emitted to a client, if the flag
H1_MF_XFER_LEN is set whereas H1_MF_CLEN and H1_MF_CHNK are not, the header
"transfer-encoding" is added. It is a way to make HTX chunking consistent with
H2. But we must exclude all cases where the message-body is explicitly forbidden
by the RFC:
* for all 1XX, 204 and 304 responses
* for any responses to HEAD requests
* for 200 responses to CONNECT requests
For these 3 cases, the flag H1_MF_XFER_LEN is set but H1_MF_CLEN and H1_MF_CHNK
not. And the header "transfer-encoding" must not be added.
See issue #27 on github for details about the bug.
This patch must be backported in 1.9.
diff --git a/src/mux_h1.c b/src/mux_h1.c
index d928cef..cce0c44 100644
--- a/src/mux_h1.c
+++ b/src/mux_h1.c
@@ -1576,7 +1576,9 @@
}
}
- if ((h1m->flags & (H1_MF_VER_11|H1_MF_RESP|H1_MF_CLEN|H1_MF_CHNK|H1_MF_XFER_LEN)) ==
+ if (h1s->status >= 200 && h1s->status != 204 && h1s->status != 304 &&
+ h1s->meth != HTTP_METH_HEAD && !(h1s->meth == HTTP_METH_CONNECT && h1s->status == 200) &&
+ (h1m->flags & (H1_MF_VER_11|H1_MF_RESP|H1_MF_CLEN|H1_MF_CHNK|H1_MF_XFER_LEN)) ==
(H1_MF_VER_11|H1_MF_RESP|H1_MF_XFER_LEN)) {
/* chunking needed but header not seen */
if (!chunk_memcat(tmp, "transfer-encoding: chunked\r\n", 28))