1 /* $NetBSD: sortlist.c,v 1.4 2014/12/10 04:37:52 christos Exp $ */
2
3 /*
4 * Copyright (C) 2004-2007 Internet Systems Consortium, Inc. ("ISC")
5 * Copyright (C) 2000, 2001 Internet Software Consortium.
6 *
7 * Permission to use, copy, modify, and/or distribute this software for any
8 * purpose with or without fee is hereby granted, provided that the above
9 * copyright notice and this permission notice appear in all copies.
10 *
11 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
12 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
13 * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
14 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
15 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
16 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
17 * PERFORMANCE OF THIS SOFTWARE.
18 */
19
20 /* Id: sortlist.c,v 1.17 2007/09/14 01:46:05 marka Exp */
21
22 /*! \file */
23
24 #include <config.h>
25
26 #include <isc/mem.h>
27 #include <isc/util.h>
28
29 #include <dns/acl.h>
30 #include <dns/result.h>
31
32 #include <named/globals.h>
33 #include <named/server.h>
34 #include <named/sortlist.h>
35
36 ns_sortlisttype_t
ns_sortlist_setup(dns_acl_t * acl,isc_netaddr_t * clientaddr,const void ** argp)37 ns_sortlist_setup(dns_acl_t *acl, isc_netaddr_t *clientaddr,
38 const void **argp)
39 {
40 unsigned int i;
41
42 if (acl == NULL)
43 goto dont_sort;
44
45 for (i = 0; i < acl->length; i++) {
46 /*
47 * 'e' refers to the current 'top level statement'
48 * in the sortlist (see ARM).
49 */
50 dns_aclelement_t *e = &acl->elements[i];
51 dns_aclelement_t *try_elt;
52 dns_aclelement_t *order_elt = NULL;
53 const dns_aclelement_t *matched_elt = NULL;
54
55 if (e->type == dns_aclelementtype_nestedacl) {
56 dns_acl_t *inner = e->nestedacl;
57
58 if (inner->length == 0)
59 try_elt = e;
60 else if (inner->length > 2)
61 goto dont_sort;
62 else if (inner->elements[0].negative)
63 goto dont_sort;
64 else {
65 try_elt = &inner->elements[0];
66 if (inner->length == 2)
67 order_elt = &inner->elements[1];
68 }
69 } else {
70 /*
71 * BIND 8 allows bare elements at the top level
72 * as an undocumented feature.
73 */
74 try_elt = e;
75 }
76
77 if (dns_aclelement_match(clientaddr, NULL, try_elt,
78 &ns_g_server->aclenv,
79 &matched_elt)) {
80 if (order_elt != NULL) {
81 if (order_elt->type ==
82 dns_aclelementtype_nestedacl) {
83 *argp = order_elt->nestedacl;
84 return (NS_SORTLISTTYPE_2ELEMENT);
85 } else if (order_elt->type ==
86 dns_aclelementtype_localhost &&
87 ns_g_server->aclenv.localhost != NULL) {
88 *argp = ns_g_server->aclenv.localhost;
89 return (NS_SORTLISTTYPE_2ELEMENT);
90 } else if (order_elt->type ==
91 dns_aclelementtype_localnets &&
92 ns_g_server->aclenv.localnets != NULL) {
93 *argp = ns_g_server->aclenv.localnets;
94 return (NS_SORTLISTTYPE_2ELEMENT);
95 } else {
96 /*
97 * BIND 8 allows a bare IP prefix as
98 * the 2nd element of a 2-element
99 * sortlist statement.
100 */
101 *argp = order_elt;
102 return (NS_SORTLISTTYPE_1ELEMENT);
103 }
104 } else {
105 INSIST(matched_elt != NULL);
106 *argp = matched_elt;
107 return (NS_SORTLISTTYPE_1ELEMENT);
108 }
109 }
110 }
111
112 /* No match; don't sort. */
113 dont_sort:
114 *argp = NULL;
115 return (NS_SORTLISTTYPE_NONE);
116 }
117
118 int
ns_sortlist_addrorder2(const isc_netaddr_t * addr,const void * arg)119 ns_sortlist_addrorder2(const isc_netaddr_t *addr, const void *arg) {
120 const dns_acl_t *sortacl = (const dns_acl_t *) arg;
121 int match;
122
123 (void)dns_acl_match(addr, NULL, sortacl,
124 &ns_g_server->aclenv,
125 &match, NULL);
126 if (match > 0)
127 return (match);
128 else if (match < 0)
129 return (INT_MAX - (-match));
130 else
131 return (INT_MAX / 2);
132 }
133
134 int
ns_sortlist_addrorder1(const isc_netaddr_t * addr,const void * arg)135 ns_sortlist_addrorder1(const isc_netaddr_t *addr, const void *arg) {
136 const dns_aclelement_t *matchelt = (const dns_aclelement_t *) arg;
137 if (dns_aclelement_match(addr, NULL, matchelt,
138 &ns_g_server->aclenv,
139 NULL)) {
140 return (0);
141 } else {
142 return (INT_MAX);
143 }
144 }
145
146 void
ns_sortlist_byaddrsetup(dns_acl_t * sortlist_acl,isc_netaddr_t * client_addr,dns_addressorderfunc_t * orderp,const void ** argp)147 ns_sortlist_byaddrsetup(dns_acl_t *sortlist_acl, isc_netaddr_t *client_addr,
148 dns_addressorderfunc_t *orderp,
149 const void **argp)
150 {
151 ns_sortlisttype_t sortlisttype;
152
153 sortlisttype = ns_sortlist_setup(sortlist_acl, client_addr, argp);
154
155 switch (sortlisttype) {
156 case NS_SORTLISTTYPE_1ELEMENT:
157 *orderp = ns_sortlist_addrorder1;
158 break;
159 case NS_SORTLISTTYPE_2ELEMENT:
160 *orderp = ns_sortlist_addrorder2;
161 break;
162 case NS_SORTLISTTYPE_NONE:
163 *orderp = NULL;
164 break;
165 default:
166 UNEXPECTED_ERROR(__FILE__, __LINE__,
167 "unexpected return from ns_sortlist_setup(): "
168 "%d", sortlisttype);
169 break;
170 }
171 }
172
173