diff --git a/src/acl.c b/src/acl.c
index c02ad70..ffed826 100644
--- a/src/acl.c
+++ b/src/acl.c
@@ -20,6 +20,28 @@
 
 #include <proto/acl.h>
 
+/* The capabilities of filtering hooks describe the type of information
+ * available to each of them.
+ */
+const unsigned int filt_cap[] = {
+	[ACL_HOOK_REQ_FE_TCP]         = ACL_USE_TCP4_ANY|ACL_USE_TCP6_ANY|ACL_USE_TCP_ANY,
+	[ACL_HOOK_REQ_FE_TCP_CONTENT] = ACL_USE_TCP4_ANY|ACL_USE_TCP6_ANY|ACL_USE_TCP_ANY|ACL_USE_L4REQ_ANY,
+	[ACL_HOOK_REQ_FE_HTTP_IN]     = ACL_USE_TCP4_ANY|ACL_USE_TCP6_ANY|ACL_USE_TCP_ANY|ACL_USE_L4REQ_ANY|ACL_USE_L7REQ_ANY|ACL_USE_HDR_ANY,
+	[ACL_HOOK_REQ_FE_SWITCH]      = ACL_USE_TCP4_ANY|ACL_USE_TCP6_ANY|ACL_USE_TCP_ANY|ACL_USE_L4REQ_ANY|ACL_USE_L7REQ_ANY|ACL_USE_HDR_ANY,
+	[ACL_HOOK_REQ_BE_TCP_CONTENT] = ACL_USE_TCP4_ANY|ACL_USE_TCP6_ANY|ACL_USE_TCP_ANY|ACL_USE_L4REQ_ANY|ACL_USE_L7REQ_ANY|ACL_USE_HDR_ANY,
+	[ACL_HOOK_REQ_BE_HTTP_IN]     = ACL_USE_TCP4_ANY|ACL_USE_TCP6_ANY|ACL_USE_TCP_ANY|ACL_USE_L4REQ_ANY|ACL_USE_L7REQ_ANY|ACL_USE_HDR_ANY,
+	[ACL_HOOK_REQ_BE_SWITCH]      = ACL_USE_TCP4_ANY|ACL_USE_TCP6_ANY|ACL_USE_TCP_ANY|ACL_USE_L4REQ_ANY|ACL_USE_L7REQ_ANY|ACL_USE_HDR_ANY,
+	[ACL_HOOK_REQ_FE_HTTP_OUT]    = ACL_USE_TCP4_ANY|ACL_USE_TCP6_ANY|ACL_USE_TCP_ANY|ACL_USE_L4REQ_ANY|ACL_USE_L7REQ_ANY|ACL_USE_HDR_ANY,
+	[ACL_HOOK_REQ_BE_HTTP_OUT]    = ACL_USE_TCP4_ANY|ACL_USE_TCP6_ANY|ACL_USE_TCP_ANY|ACL_USE_L4REQ_ANY|ACL_USE_L7REQ_ANY|ACL_USE_HDR_ANY,
+
+	[ACL_HOOK_RTR_BE_TCP_CONTENT] = ACL_USE_REQ_PERMANENT|ACL_USE_REQ_CACHEABLE|ACL_USE_L4RTR_ANY,
+	[ACL_HOOK_RTR_BE_HTTP_IN]     = ACL_USE_REQ_PERMANENT|ACL_USE_REQ_CACHEABLE|ACL_USE_L4RTR_ANY|ACL_USE_L7RTR_ANY,
+	[ACL_HOOK_RTR_FE_TCP_CONTENT] = ACL_USE_REQ_PERMANENT|ACL_USE_REQ_CACHEABLE|ACL_USE_L4RTR_ANY|ACL_USE_L7RTR_ANY,
+	[ACL_HOOK_RTR_FE_HTTP_IN]     = ACL_USE_REQ_PERMANENT|ACL_USE_REQ_CACHEABLE|ACL_USE_L4RTR_ANY|ACL_USE_L7RTR_ANY,
+	[ACL_HOOK_RTR_BE_HTTP_OUT]    = ACL_USE_REQ_PERMANENT|ACL_USE_REQ_CACHEABLE|ACL_USE_L4RTR_ANY|ACL_USE_L7RTR_ANY,
+	[ACL_HOOK_RTR_FE_HTTP_OUT]    = ACL_USE_REQ_PERMANENT|ACL_USE_REQ_CACHEABLE|ACL_USE_L4RTR_ANY|ACL_USE_L7RTR_ANY,
+};
+
 /* List head of all known ACL keywords */
 static struct acl_kw_list acl_keywords = {
 	.list = LIST_HEAD_INIT(acl_keywords.list)
@@ -753,6 +775,7 @@
 		cur_acl->name = name;
 	}
 
+	cur_acl->requires |= acl_expr->kw->requires;
 	LIST_ADDQ(&cur_acl->expr, &acl_expr->list);
 	return cur_acl;
 
@@ -919,6 +942,7 @@
 
 		cur_term->acl = cur_acl;
 		cur_term->neg = neg;
+		cond->requires |= cur_acl->requires;
 
 		if (!cur_suite) {
 			cur_suite = (struct acl_term_suite *)calloc(1, sizeof(*cur_suite));