From: Amaury Denoyelle <adenoyelle@haproxy.com>
Date: Wed, 6 Jan 2021 16:03:27 +0000 (+0100)
Subject: MINOR: connection: use sni as parameter for srv conn hash
X-Git-Tag: v2.4-dev8~70
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=9b626e3c19afa1ad1ecc623df97dc71abd7fc2a9;p=thirdparty%2Fhaproxy.git

MINOR: connection: use sni as parameter for srv conn hash

The sni parameter is an input to the server connection hash. Do not add
anymore connections with dynamic sni in the private list. Thus, it is
now possible to reuse a server connection if they use the same sni.
---

diff --git a/include/haproxy/connection-t.h b/include/haproxy/connection-t.h
index a8239b43fe..9ee00819bf 100644
--- a/include/haproxy/connection-t.h
+++ b/include/haproxy/connection-t.h
@@ -33,6 +33,7 @@
 #include <import/xxhash.h>
 
 #include <haproxy/api-t.h>
+#include <haproxy/buf-t.h>
 #include <haproxy/listener-t.h>
 #include <haproxy/obj_type-t.h>
 #include <haproxy/port_range-t.h>
@@ -471,8 +472,7 @@ struct conn_stream {
  * CAUTION! Always update CONN_HASH_PARAMS_TYPE_COUNT when adding a new entry.
  */
 enum conn_hash_params_t {
-	/* to remove as soon as one useful parameter is present */
-	CONN_HASH_DUMMY_PARAM,
+	CONN_HASH_PARAMS_TYPE_SNI = 0x1,
 };
 #define CONN_HASH_PARAMS_TYPE_COUNT 1
 
@@ -488,6 +488,7 @@ enum conn_hash_params_t {
  */
 struct conn_hash_params {
 	struct server *srv;
+	XXH64_hash_t *sni_prehash;
 };
 
 /* This structure describes a connection with its methods and data.
diff --git a/src/backend.c b/src/backend.c
index fed177c9bd..d9d5c97e19 100644
--- a/src/backend.c
+++ b/src/backend.c
@@ -1246,8 +1246,10 @@ int connect_server(struct stream *s)
 	int reuse = 0;
 	int init_mux = 0;
 	int err;
+	struct sample *sni_smp = NULL;
 	int64_t hash = 0;
 	struct conn_hash_params hash_params;
+	XXH64_hash_t sni_hash;
 
 	/* first, set unique connection parameters and then calculate hash */
 	memset(&hash_params, 0, sizeof(hash_params));
@@ -1255,6 +1257,20 @@ int connect_server(struct stream *s)
 	srv = objt_server(s->target);
 	hash_params.srv = srv;
 
+#ifdef USE_OPENSSL
+	/* 1. sni */
+	if (srv && srv->ssl_ctx.sni) {
+		sni_smp = sample_fetch_as_type(s->be, s->sess, s,
+		                               SMP_OPT_DIR_REQ | SMP_OPT_FINAL,
+		                               srv->ssl_ctx.sni, SMP_T_STR);
+		if (smp_make_safe(sni_smp)) {
+			sni_hash = conn_hash_prehash(sni_smp->data.u.str.area,
+			                             sni_smp->data.u.str.data);
+			hash_params.sni_prehash = &sni_hash;
+		}
+	}
+#endif /* USE_OPENSSL */
+
 	if (srv)
 		hash = conn_calculate_hash(&hash_params);
 
@@ -1547,19 +1563,8 @@ skip_reuse:
 		return err;
 
 #ifdef USE_OPENSSL
-	if (srv && srv->ssl_ctx.sni) {
-		struct sample *smp;
-
-		smp = sample_fetch_as_type(s->be, s->sess, s, SMP_OPT_DIR_REQ | SMP_OPT_FINAL,
-					   srv->ssl_ctx.sni, SMP_T_STR);
-		if (smp_make_safe(smp)) {
-			ssl_sock_set_servername(srv_conn, smp->data.u.str.area);
-			if (!(srv->ssl_ctx.sni->fetch->use & SMP_USE_INTRN) ||
-			    smp->flags & SMP_F_VOLATILE) {
-				conn_set_private(srv_conn);
-			}
-		}
-	}
+	if (smp_make_safe(sni_smp))
+		ssl_sock_set_servername(srv_conn, sni_smp->data.u.str.area);
 #endif /* USE_OPENSSL */
 
 	/* The CO_FL_SEND_PROXY flag may have been set by the connect method,
diff --git a/src/connection.c b/src/connection.c
index 3656b36366..6126dd1803 100644
--- a/src/connection.c
+++ b/src/connection.c
@@ -1423,6 +1423,12 @@ XXH64_hash_t conn_calculate_hash(const struct conn_hash_params *params)
 
 	conn_hash_update(buf, &idx, &params->srv, sizeof(params->srv), &hash_flags, 0);
 
+	if (params->sni_prehash) {
+		conn_hash_update(buf, &idx,
+		                 params->sni_prehash, sizeof(*params->sni_prehash),
+		                 &hash_flags, CONN_HASH_PARAMS_TYPE_SNI);
+	}
+
 	hash = conn_hash_digest(buf, idx, hash_flags);
 	return hash;
 }