Add a new VCL variable "client.identity" which defaults to client.ip

(without port number).

This variable is used by the "client" director to distribute sessions
across multiple backends.

Having it be a separate variable from client.ip makes it possible to
fill it from X-Forwarded-For: or Cookie headers.



git-svn-id: http://www.varnish-cache.org/svn/trunk/varnish-cache@5080 d4fa192b-c00b-0410-8231-f00ffab90ce4

bin/varnishd/cache.h

@@ -390,6 +390,7 @@ struct sess {
 	/* formatted ascii client address */
 	char			*addr;
 	char			*port;
+	char			*client_identity;
 
 	/* HTTP request */
 	const char		*doclose;

bin/varnishd/cache_center.c

@@ -1038,6 +1038,7 @@ cnt_recv(struct sess *sp)
 
 	sp->disable_esi = 0;
 	sp->pass = 0;
+	sp->client_identity = NULL;
 
 	VCL_recv_method(sp);
 	recv_handling = sp->handling;

bin/varnishd/cache_dir_random.c

@@ -106,7 +106,11 @@ vdi_random_getfd(const struct director *d, struct sess *sp)
 		 */
 		SHA256_Init(&ctx);
 		AN(sp->addr);
-		SHA256_Update(&ctx, sp->addr, strlen(sp->addr));
+		if (sp->client_identity != NULL)
+			SHA256_Update(&ctx, sp->client_identity,
+			    strlen(sp->client_identity));
+		else
+			SHA256_Update(&ctx, sp->addr, strlen(sp->addr));
 		SHA256_Final(sign, &ctx);
 		hp = sign;
 	}

bin/varnishd/cache_vrt.c

@@ -371,7 +371,7 @@ VRT_r_resp_status(const struct sess *sp)
 
 /*--------------------------------------------------------------------*/
 
-#define VBEREQ(dir, type,onm,field)					\
+#define VBEREQ(dir, type, onm, field)					\
 void									\
 VRT_l_##dir##_##onm(const struct sess *sp, type a)			\
 {									\
@@ -389,6 +389,30 @@ VRT_r_##dir##_##onm(const struct sess *sp)				\
 VBEREQ(beresp, unsigned, cacheable, cacheable)
 VBEREQ(beresp, double, grace, grace)
 
+/*--------------------------------------------------------------------*/
+
+const char *
+VRT_r_client_identity(struct sess *sp)
+{
+	CHECK_OBJ_NOTNULL(sp, SESS_MAGIC);
+	if (sp->client_identity != NULL)
+		return (sp->client_identity);
+	else
+		return (sp->addr);
+}
+
+void
+VRT_l_client_identity(struct sess *sp, const char *str, ...)
+{
+	va_list ap;
+	char *b;
+
+	va_start(ap, str);
+	b = vrt_assemble_string(sp->http, NULL, str, ap);
+	va_end(ap);
+	sp->client_identity = b;
+}
+
 /*--------------------------------------------------------------------
  * XXX: Working relative to t_req is maybe not the right thing, we could
  * XXX: have spent a long time talking to the backend since then.

bin/varnishd/mgt_cli.c

@@ -187,8 +187,7 @@ mcf_askchild(struct cli *cli, const char * const *av, void *priv)
 	}
 
 	assert(i == 1 || errno == EPIPE);
-	(void)cli_readres(cli_i,
-	    &u, &q, params->cli_timeout);
+	(void)cli_readres(cli_i, &u, &q, params->cli_timeout);
 	cli_result(cli, u);
 	cli_out(cli, "%s", q);
 	free(q);

bin/varnishtest/tests/v00028.vtc

+# $Id$
+
+test "Client director"
+
+server s1 {
+	rxreq
+	txresp -hdr "be: s1" -bodylen 1
+} -start
+
+server s2 {
+	rxreq
+	txresp -hdr "be: s2" -bodylen 2
+	rxreq
+	txresp -hdr "be: s2" -bodylen 4
+} -start
+
+varnish v1 -vcl+backend {
+	director d1 client {
+		{ .backend = s1; .weight = 1; }
+		{ .backend = s2; .weight = 1; }
+	}
+
+	sub vcl_recv {
+		set req.backend = d1;
+		if (req.http.id) {
+			set client.identity = req.http.id;
+		}
+		return (pass);
+	}
+	sub vcl_deliver {
+		set resp.http.id = client.identity;
+	}
+} -start
+
+
+client c1 {
+	txreq
+	rxresp
+	expect resp.http.id == "127.0.0.1"
+	expect resp.http.be == s2
+	expect resp.bodylen == 2
+
+	txreq -hdr "id: foo"
+	rxresp
+	expect resp.http.id == "foo"
+	expect resp.http.be == s1
+	expect resp.bodylen == 1
+
+	txreq -hdr "id: baz"
+	rxresp
+	expect resp.http.id == "baz"
+	expect resp.http.be == s2
+	expect resp.bodylen == 4
+} -run
+
+

lib/libvcl/generate.py

@@ -106,6 +106,12 @@ sp_variables = (
 		( ),
 		'const struct sess *'
 	),
+	('client.identity',
+		'STRING',
+		( 'all',),
+		( 'all',),
+		'struct sess *'
+	),
 	('server.ip',
 		'IP',
 		( 'all',),