MEDIUM: http: add a new option http-buffer-request
It is sometimes desirable to wait for the body of an HTTP request before
taking a decision. This is what is being done by "balance url_param" for
example. The first use case is to buffer requests from slow clients before
connecting to the server. Another use case consists in taking the routing
decision based on the request body's contents. This option placed in a
frontend or backend forces the HTTP processing to wait until either the whole
body is received, or the request buffer is full, or the first chunk is
complete in case of chunked encoding. It can have undesired side effects with
some applications abusing HTTP by expecting unbufferred transmissions between
the frontend and the backend, so this should definitely not be used by
default.
Note that it would not work for the response because we don't reset the
message state before starting to forward. For the response we need to
1) reset the message state to MSG_100_SENT or BODY , and 2) to reset
body_len in case of chunked encoding to avoid counting it twice.
diff --git a/doc/configuration.txt b/doc/configuration.txt
index 2dab50a..69dfbe7 100644
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -1482,6 +1482,7 @@
option forceclose (*) X X X X
-- keyword -------------------------- defaults - frontend - listen -- backend -
option forwardfor X X X X
+option http-buffer-request (*) X X X X
option http-ignore-probes (*) X X X -
option http-keep-alive (*) X X X X
option http-no-delay (*) X X X X
@@ -4453,6 +4454,28 @@
"option forceclose", "option http-keep-alive"
+option http-buffer-request
+no option http-buffer-request
+ Enable or disable waiting for whole HTTP request body before proceeding
+ May be used in sections : defaults | frontend | listen | backend
+ yes | yes | yes | yes
+ Arguments : none
+
+ It is sometimes desirable to wait for the body of an HTTP request before
+ taking a decision. This is what is being done by "balance url_param" for
+ example. The first use case is to buffer requests from slow clients before
+ connecting to the server. Another use case consists in taking the routing
+ decision based on the request body's contents. This option placed in a
+ frontend or backend forces the HTTP processing to wait until either the whole
+ body is received, or the request buffer is full, or the first chunk is
+ complete in case of chunked encoding. It can have undesired side effects with
+ some applications abusing HTTP by expecting unbufferred transmissions between
+ the frontend and the backend, so this should definitely not be used by
+ default.
+
+ See also : "option http-no-delay"
+
+
option http-ignore-probes
no option http-ignore-probes
Enable or disable logging of null connections and request timeouts
@@ -4578,6 +4601,8 @@
usage and CPU usage, which may significantly lower performance in high
latency environments.
+ See also : "option http-buffer-request"
+
option http-pretend-keepalive
no option http-pretend-keepalive
diff --git a/include/types/proxy.h b/include/types/proxy.h
index 34501f2..826a0f2 100644
--- a/include/types/proxy.h
+++ b/include/types/proxy.h
@@ -83,7 +83,8 @@
#define PR_O_FWDFOR 0x00000100 /* conditionally insert x-forwarded-for with client address */
#define PR_O_IGNORE_PRB 0x00000200 /* ignore empty requests (aborts and timeouts) */
#define PR_O_NULLNOLOG 0x00000400 /* a connect without request will not be logged */
-/* unused: 0x0800, 0x1000 */
+#define PR_O_WREQ_BODY 0x00000800 /* always wait for the HTTP request body */
+/* unused: 0x1000 */
#define PR_O_FF_ALWAYS 0x00002000 /* always set x-forwarded-for */
#define PR_O_PERSIST 0x00004000 /* server persistence stays effective even when server is down */
#define PR_O_LOGASAP 0x00008000 /* log as soon as possible, without waiting for the stream to complete */
diff --git a/src/cfgparse.c b/src/cfgparse.c
index e8004c6..8578bc5 100644
--- a/src/cfgparse.c
+++ b/src/cfgparse.c
@@ -154,6 +154,7 @@
{ "contstats", PR_O_CONTSTATS, PR_CAP_FE, 0, 0 },
{ "dontlognull", PR_O_NULLNOLOG, PR_CAP_FE, 0, 0 },
{ "http_proxy", PR_O_HTTP_PROXY, PR_CAP_FE | PR_CAP_BE, 0, PR_MODE_HTTP },
+ { "http-buffer-request", PR_O_WREQ_BODY, PR_CAP_FE | PR_CAP_BE, 0, PR_MODE_HTTP },
{ "http-ignore-probes", PR_O_IGNORE_PRB, PR_CAP_FE, 0, PR_MODE_HTTP },
{ "prefer-last-server", PR_O_PREF_LAST, PR_CAP_BE, 0, PR_MODE_HTTP },
{ "logasap", PR_O_LOGASAP, PR_CAP_FE, 0, 0 },
diff --git a/src/proto_http.c b/src/proto_http.c
index dc59981..6bd89bc 100644
--- a/src/proto_http.c
+++ b/src/proto_http.c
@@ -3133,6 +3133,11 @@
((sess->fe->options & PR_O_HTTP_MODE) != (s->be->options & PR_O_HTTP_MODE)))
http_adjust_conn_mode(s, txn, msg);
+ /* we may have to wait for the request's body */
+ if ((s->be->options & PR_O_WREQ_BODY) &&
+ (msg->body_len || (msg->flags & HTTP_MSGF_TE_CHNK)))
+ req->analysers |= AN_REQ_HTTP_BODY;
+
/* end of job, return OK */
req->analysers &= ~an_bit;
req->analyse_exp = TICK_ETERNITY;
@@ -3288,7 +3293,7 @@
}
/* Was the status page requested with a POST ? */
- if (unlikely(txn->meth == HTTP_METH_POST && txn->req.body_len > 0)) {
+ if (unlikely(txn->meth == HTTP_METH_POST && txn->req.body_len > 0 && msg->msg_state < HTTP_MSG_BODY)) {
if (appctx->ctx.stats.flags & STAT_ADMIN) {
/* we'll need the request body, possibly after sending 100-continue */
req->analysers |= AN_REQ_HTTP_BODY;
diff --git a/src/proxy.c b/src/proxy.c
index 12e8aa3..ed3b582 100644
--- a/src/proxy.c
+++ b/src/proxy.c
@@ -940,6 +940,13 @@
if (be->options2 & PR_O2_INDEPSTR)
s->si[1].flags |= SI_FL_INDEP_STR;
+ /* We want to enable the backend-specific analysers except those which
+ * were already run as part of the frontend/listener. Note that it would
+ * be more reliable to store the list of analysers that have been run,
+ * but what we do here is OK for now.
+ */
+ s->req.analysers |= be->be_req_ana & ~strm_li(s)->analysers;
+
/* If the target backend requires HTTP processing, we have to allocate
* the HTTP transaction and hdr_idx if we did not have one.
*/
@@ -971,6 +978,11 @@
if (be->mode == PR_MODE_HTTP &&
(be->lbprm.algo & (BE_LB_KIND | BE_LB_PARM)) == (BE_LB_KIND_HI | BE_LB_HASH_PRM))
s->txn->req.flags |= HTTP_MSGF_WAIT_CONN;
+
+ /* we may request to parse a request body */
+ if ((be->options & PR_O_WREQ_BODY) &&
+ (s->txn->req.body_len || (s->txn->req.flags & HTTP_MSGF_TE_CHNK)))
+ s->req.analysers |= AN_REQ_HTTP_BODY;
}
s->flags |= SF_BE_ASSIGNED;
@@ -979,13 +991,6 @@
s->res.flags |= CF_NEVER_WAIT;
}
- /* We want to enable the backend-specific analysers except those which
- * were already run as part of the frontend/listener. Note that it would
- * be more reliable to store the list of analysers that have been run,
- * but what we do here is OK for now.
- */
- s->req.analysers |= be->be_req_ana & ~strm_li(s)->analysers;
-
return 1;
}