BUG/MINOR: http-check: Don't pretend a C-L heeader is set before adding it

When a GET/HEAD/OPTIONS/DELETE healthcheck request was formatted, we claimed
there was a "content-length" header set even when there was no payload,
leading to actually send a "content-length: 0" header to the server. It was
unexpected and could be rejected by servers.

When a healthcheck request is sent we must take care to state there is a
"content-length" header when it is explicitly added.

This patch should fix the issue #2851. It must be backported as far as 2.9.

diff --git a/src/tcpcheck.c b/src/tcpcheck.c
index 6e12eb6c28ca41ba92ac388498c3e77346ce23af..a366b9e59b4ac378a2286f84275c756753867bde 100644 (file)
--- a/src/tcpcheck.c
+++ b/src/tcpcheck.c
@@ -1569,7 +1569,7 @@ enum tcpcheck_eval_ret tcpcheck_eval_send(struct check *check, struct tcpcheck_r
                if ((istlen(vsn) == 6 && *(vsn.ptr+5) == '2') ||
                    (istlen(vsn) == 8 && (*(vsn.ptr+5) > '1' || (*(vsn.ptr+5) == '1' && *(vsn.ptr+7) >= '1'))))
                        slflags |= HTX_SL_F_VER_11;
-               slflags |= (HTX_SL_F_XFER_LEN|HTX_SL_F_CLEN);
+               slflags |= HTX_SL_F_XFER_LEN;
                if (!(send->http.flags & TCPCHK_SND_HTTP_FL_BODY_FMT) && !isttest(send->http.body))
                        slflags |= HTX_SL_F_BODYLESS;
 
@@ -1628,6 +1628,7 @@ enum tcpcheck_eval_ret tcpcheck_eval_send(struct check *check, struct tcpcheck_r
                        clen = ist((!istlen(body) ? "0" : ultoa(istlen(body))));
                        if (!htx_add_header(htx, ist("Content-length"), clen))
                                goto error_htx;
+                       sl->flags |= HTX_SL_F_CLEN;
                }
 
                if (!htx_add_endof(htx, HTX_BLK_EOH) ||