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1/*
2 * xfrm6_policy.c: based on xfrm4_policy.c
3 *
4 * Authors:
5 * Mitsuru KANDA @USAGI
6 * Kazunori MIYAZAWA @USAGI
7 * Kunihiro Ishiguro <kunihiro@ipinfusion.com>
8 * IPv6 support
9 * YOSHIFUJI Hideaki
10 * Split up af-specific portion
11 *
12 */
13
14#include <linux/err.h>
15#include <linux/kernel.h>
16#include <linux/netdevice.h>
17#include <net/addrconf.h>
18#include <net/dst.h>
19#include <net/xfrm.h>
20#include <net/ip.h>
21#include <net/ipv6.h>
22#include <net/ip6_route.h>
23#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
24#include <net/mip6.h>
25#endif
26
27static struct xfrm_policy_afinfo xfrm6_policy_afinfo;
28
29static struct dst_entry *xfrm6_dst_lookup(struct net *net, int tos,
30 const xfrm_address_t *saddr,
31 const xfrm_address_t *daddr)
32{
33 struct flowi6 fl6;
34 struct dst_entry *dst;
35 int err;
36
37 memset(&fl6, 0, sizeof(fl6));
38 memcpy(&fl6.daddr, daddr, sizeof(fl6.daddr));
39 if (saddr)
40 memcpy(&fl6.saddr, saddr, sizeof(fl6.saddr));
41
42 dst = ip6_route_output(net, NULL, &fl6);
43
44 err = dst->error;
45 if (dst->error) {
46 dst_release(dst);
47 dst = ERR_PTR(err);
48 }
49
50 return dst;
51}
52
53static int xfrm6_get_saddr(struct net *net,
54 xfrm_address_t *saddr, xfrm_address_t *daddr)
55{
56 struct dst_entry *dst;
57 struct net_device *dev;
58
59 dst = xfrm6_dst_lookup(net, 0, NULL, daddr);
60 if (IS_ERR(dst))
61 return -EHOSTUNREACH;
62
63 dev = ip6_dst_idev(dst)->dev;
64 ipv6_dev_get_saddr(dev_net(dev), dev,
65 (struct in6_addr *)&daddr->a6, 0,
66 (struct in6_addr *)&saddr->a6);
67 dst_release(dst);
68 return 0;
69}
70
71static int xfrm6_get_tos(const struct flowi *fl)
72{
73 return 0;
74}
75
76static int xfrm6_init_path(struct xfrm_dst *path, struct dst_entry *dst,
77 int nfheader_len)
78{
79 if (dst->ops->family == AF_INET6) {
80 struct rt6_info *rt = (struct rt6_info*)dst;
81 if (rt->rt6i_node)
82 path->path_cookie = rt->rt6i_node->fn_sernum;
83 }
84
85 path->u.rt6.rt6i_nfheader_len = nfheader_len;
86
87 return 0;
88}
89
90static int xfrm6_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
91 const struct flowi *fl)
92{
93 struct rt6_info *rt = (struct rt6_info*)xdst->route;
94
95 xdst->u.dst.dev = dev;
96 dev_hold(dev);
97
98 xdst->u.rt6.rt6i_idev = in6_dev_get(dev);
99 if (!xdst->u.rt6.rt6i_idev)
100 return -ENODEV;
101
102 xdst->u.rt6.rt6i_peer = rt->rt6i_peer;
103 if (rt->rt6i_peer)
104 atomic_inc(&rt->rt6i_peer->refcnt);
105
106 /* Sheit... I remember I did this right. Apparently,
107 * it was magically lost, so this code needs audit */
108 xdst->u.rt6.rt6i_flags = rt->rt6i_flags & (RTF_ANYCAST |
109 RTF_LOCAL);
110 xdst->u.rt6.rt6i_metric = rt->rt6i_metric;
111 xdst->u.rt6.rt6i_node = rt->rt6i_node;
112 if (rt->rt6i_node)
113 xdst->route_cookie = rt->rt6i_node->fn_sernum;
114 xdst->u.rt6.rt6i_gateway = rt->rt6i_gateway;
115 xdst->u.rt6.rt6i_dst = rt->rt6i_dst;
116 xdst->u.rt6.rt6i_src = rt->rt6i_src;
117
118 return 0;
119}
120
121static inline void
122_decode_session6(struct sk_buff *skb, struct flowi *fl, int reverse)
123{
124 struct flowi6 *fl6 = &fl->u.ip6;
125 int onlyproto = 0;
126 u16 offset = skb_network_header_len(skb);
127 const struct ipv6hdr *hdr = ipv6_hdr(skb);
128 struct ipv6_opt_hdr *exthdr;
129 const unsigned char *nh = skb_network_header(skb);
130 u8 nexthdr = nh[IP6CB(skb)->nhoff];
131
132 memset(fl6, 0, sizeof(struct flowi6));
133 fl6->flowi6_mark = skb->mark;
134
135 fl6->daddr = reverse ? hdr->saddr : hdr->daddr;
136 fl6->saddr = reverse ? hdr->daddr : hdr->saddr;
137
138 while (nh + offset + 1 < skb->data ||
139 pskb_may_pull(skb, nh + offset + 1 - skb->data)) {
140 nh = skb_network_header(skb);
141 exthdr = (struct ipv6_opt_hdr *)(nh + offset);
142
143 switch (nexthdr) {
144 case NEXTHDR_FRAGMENT:
145 onlyproto = 1;
146 case NEXTHDR_ROUTING:
147 case NEXTHDR_HOP:
148 case NEXTHDR_DEST:
149 offset += ipv6_optlen(exthdr);
150 nexthdr = exthdr->nexthdr;
151 exthdr = (struct ipv6_opt_hdr *)(nh + offset);
152 break;
153
154 case IPPROTO_UDP:
155 case IPPROTO_UDPLITE:
156 case IPPROTO_TCP:
157 case IPPROTO_SCTP:
158 case IPPROTO_DCCP:
159 if (!onlyproto && (nh + offset + 4 < skb->data ||
160 pskb_may_pull(skb, nh + offset + 4 - skb->data))) {
161 __be16 *ports = (__be16 *)exthdr;
162
163 fl6->fl6_sport = ports[!!reverse];
164 fl6->fl6_dport = ports[!reverse];
165 }
166 fl6->flowi6_proto = nexthdr;
167 return;
168
169 case IPPROTO_ICMPV6:
170 if (!onlyproto && pskb_may_pull(skb, nh + offset + 2 - skb->data)) {
171 u8 *icmp = (u8 *)exthdr;
172
173 fl6->fl6_icmp_type = icmp[0];
174 fl6->fl6_icmp_code = icmp[1];
175 }
176 fl6->flowi6_proto = nexthdr;
177 return;
178
179#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
180 case IPPROTO_MH:
181 if (!onlyproto && pskb_may_pull(skb, nh + offset + 3 - skb->data)) {
182 struct ip6_mh *mh;
183 mh = (struct ip6_mh *)exthdr;
184
185 fl6->fl6_mh_type = mh->ip6mh_type;
186 }
187 fl6->flowi6_proto = nexthdr;
188 return;
189#endif
190
191 /* XXX Why are there these headers? */
192 case IPPROTO_AH:
193 case IPPROTO_ESP:
194 case IPPROTO_COMP:
195 default:
196 fl6->fl6_ipsec_spi = 0;
197 fl6->flowi6_proto = nexthdr;
198 return;
199 }
200 }
201}
202
203static inline int xfrm6_garbage_collect(struct dst_ops *ops)
204{
205 struct net *net = container_of(ops, struct net, xfrm.xfrm6_dst_ops);
206
207 xfrm6_policy_afinfo.garbage_collect(net);
208 return dst_entries_get_fast(ops) > ops->gc_thresh * 2;
209}
210
211static void xfrm6_update_pmtu(struct dst_entry *dst, u32 mtu)
212{
213 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
214 struct dst_entry *path = xdst->route;
215
216 path->ops->update_pmtu(path, mtu);
217}
218
219static void xfrm6_dst_destroy(struct dst_entry *dst)
220{
221 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
222
223 if (likely(xdst->u.rt6.rt6i_idev))
224 in6_dev_put(xdst->u.rt6.rt6i_idev);
225 dst_destroy_metrics_generic(dst);
226 if (likely(xdst->u.rt6.rt6i_peer))
227 inet_putpeer(xdst->u.rt6.rt6i_peer);
228 xfrm_dst_destroy(xdst);
229}
230
231static void xfrm6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
232 int unregister)
233{
234 struct xfrm_dst *xdst;
235
236 if (!unregister)
237 return;
238
239 xdst = (struct xfrm_dst *)dst;
240 if (xdst->u.rt6.rt6i_idev->dev == dev) {
241 struct inet6_dev *loopback_idev =
242 in6_dev_get(dev_net(dev)->loopback_dev);
243 BUG_ON(!loopback_idev);
244
245 do {
246 in6_dev_put(xdst->u.rt6.rt6i_idev);
247 xdst->u.rt6.rt6i_idev = loopback_idev;
248 in6_dev_hold(loopback_idev);
249 xdst = (struct xfrm_dst *)xdst->u.dst.child;
250 } while (xdst->u.dst.xfrm);
251
252 __in6_dev_put(loopback_idev);
253 }
254
255 xfrm_dst_ifdown(dst, dev);
256}
257
258static struct dst_ops xfrm6_dst_ops = {
259 .family = AF_INET6,
260 .protocol = cpu_to_be16(ETH_P_IPV6),
261 .gc = xfrm6_garbage_collect,
262 .update_pmtu = xfrm6_update_pmtu,
263 .cow_metrics = dst_cow_metrics_generic,
264 .destroy = xfrm6_dst_destroy,
265 .ifdown = xfrm6_dst_ifdown,
266 .local_out = __ip6_local_out,
267 .gc_thresh = 1024,
268};
269
270static struct xfrm_policy_afinfo xfrm6_policy_afinfo = {
271 .family = AF_INET6,
272 .dst_ops = &xfrm6_dst_ops,
273 .dst_lookup = xfrm6_dst_lookup,
274 .get_saddr = xfrm6_get_saddr,
275 .decode_session = _decode_session6,
276 .get_tos = xfrm6_get_tos,
277 .init_path = xfrm6_init_path,
278 .fill_dst = xfrm6_fill_dst,
279 .blackhole_route = ip6_blackhole_route,
280};
281
282static int __init xfrm6_policy_init(void)
283{
284 return xfrm_policy_register_afinfo(&xfrm6_policy_afinfo);
285}
286
287static void xfrm6_policy_fini(void)
288{
289 xfrm_policy_unregister_afinfo(&xfrm6_policy_afinfo);
290}
291
292#ifdef CONFIG_SYSCTL
293static struct ctl_table xfrm6_policy_table[] = {
294 {
295 .procname = "xfrm6_gc_thresh",
296 .data = &init_net.xfrm.xfrm6_dst_ops.gc_thresh,
297 .maxlen = sizeof(int),
298 .mode = 0644,
299 .proc_handler = proc_dointvec,
300 },
301 { }
302};
303
304static struct ctl_table_header *sysctl_hdr;
305#endif
306
307int __init xfrm6_init(void)
308{
309 int ret;
310 unsigned int gc_thresh;
311
312 /*
313 * We need a good default value for the xfrm6 gc threshold.
314 * In ipv4 we set it to the route hash table size * 8, which
315 * is half the size of the maximaum route cache for ipv4. It
316 * would be good to do the same thing for v6, except the table is
317 * constructed differently here. Here each table for a net namespace
318 * can have FIB_TABLE_HASHSZ entries, so lets go with the same
319 * computation that we used for ipv4 here. Also, lets keep the initial
320 * gc_thresh to a minimum of 1024, since, the ipv6 route cache defaults
321 * to that as a minimum as well
322 */
323 gc_thresh = FIB6_TABLE_HASHSZ * 8;
324 xfrm6_dst_ops.gc_thresh = (gc_thresh < 1024) ? 1024 : gc_thresh;
325 dst_entries_init(&xfrm6_dst_ops);
326
327 ret = xfrm6_policy_init();
328 if (ret) {
329 dst_entries_destroy(&xfrm6_dst_ops);
330 goto out;
331 }
332 ret = xfrm6_state_init();
333 if (ret)
334 goto out_policy;
335
336#ifdef CONFIG_SYSCTL
337 sysctl_hdr = register_net_sysctl(&init_net, "net/ipv6",
338 xfrm6_policy_table);
339#endif
340out:
341 return ret;
342out_policy:
343 xfrm6_policy_fini();
344 goto out;
345}
346
347void xfrm6_fini(void)
348{
349#ifdef CONFIG_SYSCTL
350 if (sysctl_hdr)
351 unregister_net_sysctl_table(sysctl_hdr);
352#endif
353 //xfrm6_input_fini();
354 xfrm6_policy_fini();
355 xfrm6_state_fini();
356 dst_entries_destroy(&xfrm6_dst_ops);
357}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * xfrm6_policy.c: based on xfrm4_policy.c
4 *
5 * Authors:
6 * Mitsuru KANDA @USAGI
7 * Kazunori MIYAZAWA @USAGI
8 * Kunihiro Ishiguro <kunihiro@ipinfusion.com>
9 * IPv6 support
10 * YOSHIFUJI Hideaki
11 * Split up af-specific portion
12 *
13 */
14
15#include <linux/err.h>
16#include <linux/kernel.h>
17#include <linux/netdevice.h>
18#include <net/addrconf.h>
19#include <net/dst.h>
20#include <net/xfrm.h>
21#include <net/ip.h>
22#include <net/ipv6.h>
23#include <net/ip6_route.h>
24#include <net/l3mdev.h>
25
26static struct dst_entry *xfrm6_dst_lookup(struct net *net, int tos, int oif,
27 const xfrm_address_t *saddr,
28 const xfrm_address_t *daddr,
29 u32 mark)
30{
31 struct flowi6 fl6;
32 struct dst_entry *dst;
33 int err;
34
35 memset(&fl6, 0, sizeof(fl6));
36 fl6.flowi6_oif = l3mdev_master_ifindex_by_index(net, oif);
37 fl6.flowi6_flags = FLOWI_FLAG_SKIP_NH_OIF;
38 fl6.flowi6_mark = mark;
39 memcpy(&fl6.daddr, daddr, sizeof(fl6.daddr));
40 if (saddr)
41 memcpy(&fl6.saddr, saddr, sizeof(fl6.saddr));
42
43 dst = ip6_route_output(net, NULL, &fl6);
44
45 err = dst->error;
46 if (dst->error) {
47 dst_release(dst);
48 dst = ERR_PTR(err);
49 }
50
51 return dst;
52}
53
54static int xfrm6_get_saddr(struct net *net, int oif,
55 xfrm_address_t *saddr, xfrm_address_t *daddr,
56 u32 mark)
57{
58 struct dst_entry *dst;
59 struct net_device *dev;
60
61 dst = xfrm6_dst_lookup(net, 0, oif, NULL, daddr, mark);
62 if (IS_ERR(dst))
63 return -EHOSTUNREACH;
64
65 dev = ip6_dst_idev(dst)->dev;
66 ipv6_dev_get_saddr(dev_net(dev), dev, &daddr->in6, 0, &saddr->in6);
67 dst_release(dst);
68 return 0;
69}
70
71static int xfrm6_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
72 const struct flowi *fl)
73{
74 struct rt6_info *rt = (struct rt6_info *)xdst->route;
75
76 xdst->u.dst.dev = dev;
77 dev_hold(dev);
78
79 xdst->u.rt6.rt6i_idev = in6_dev_get(dev);
80 if (!xdst->u.rt6.rt6i_idev) {
81 dev_put(dev);
82 return -ENODEV;
83 }
84
85 /* Sheit... I remember I did this right. Apparently,
86 * it was magically lost, so this code needs audit */
87 xdst->u.rt6.rt6i_flags = rt->rt6i_flags & (RTF_ANYCAST |
88 RTF_LOCAL);
89 xdst->route_cookie = rt6_get_cookie(rt);
90 xdst->u.rt6.rt6i_gateway = rt->rt6i_gateway;
91 xdst->u.rt6.rt6i_dst = rt->rt6i_dst;
92 xdst->u.rt6.rt6i_src = rt->rt6i_src;
93 INIT_LIST_HEAD(&xdst->u.rt6.rt6i_uncached);
94 rt6_uncached_list_add(&xdst->u.rt6);
95 atomic_inc(&dev_net(dev)->ipv6.rt6_stats->fib_rt_uncache);
96
97 return 0;
98}
99
100static void xfrm6_update_pmtu(struct dst_entry *dst, struct sock *sk,
101 struct sk_buff *skb, u32 mtu,
102 bool confirm_neigh)
103{
104 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
105 struct dst_entry *path = xdst->route;
106
107 path->ops->update_pmtu(path, sk, skb, mtu, confirm_neigh);
108}
109
110static void xfrm6_redirect(struct dst_entry *dst, struct sock *sk,
111 struct sk_buff *skb)
112{
113 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
114 struct dst_entry *path = xdst->route;
115
116 path->ops->redirect(path, sk, skb);
117}
118
119static void xfrm6_dst_destroy(struct dst_entry *dst)
120{
121 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
122
123 if (likely(xdst->u.rt6.rt6i_idev))
124 in6_dev_put(xdst->u.rt6.rt6i_idev);
125 dst_destroy_metrics_generic(dst);
126 if (xdst->u.rt6.rt6i_uncached_list)
127 rt6_uncached_list_del(&xdst->u.rt6);
128 xfrm_dst_destroy(xdst);
129}
130
131static void xfrm6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
132 int unregister)
133{
134 struct xfrm_dst *xdst;
135
136 if (!unregister)
137 return;
138
139 xdst = (struct xfrm_dst *)dst;
140 if (xdst->u.rt6.rt6i_idev->dev == dev) {
141 struct inet6_dev *loopback_idev =
142 in6_dev_get(dev_net(dev)->loopback_dev);
143
144 do {
145 in6_dev_put(xdst->u.rt6.rt6i_idev);
146 xdst->u.rt6.rt6i_idev = loopback_idev;
147 in6_dev_hold(loopback_idev);
148 xdst = (struct xfrm_dst *)xfrm_dst_child(&xdst->u.dst);
149 } while (xdst->u.dst.xfrm);
150
151 __in6_dev_put(loopback_idev);
152 }
153
154 xfrm_dst_ifdown(dst, dev);
155}
156
157static struct dst_ops xfrm6_dst_ops_template = {
158 .family = AF_INET6,
159 .update_pmtu = xfrm6_update_pmtu,
160 .redirect = xfrm6_redirect,
161 .cow_metrics = dst_cow_metrics_generic,
162 .destroy = xfrm6_dst_destroy,
163 .ifdown = xfrm6_dst_ifdown,
164 .local_out = __ip6_local_out,
165 .gc_thresh = 32768,
166};
167
168static const struct xfrm_policy_afinfo xfrm6_policy_afinfo = {
169 .dst_ops = &xfrm6_dst_ops_template,
170 .dst_lookup = xfrm6_dst_lookup,
171 .get_saddr = xfrm6_get_saddr,
172 .fill_dst = xfrm6_fill_dst,
173 .blackhole_route = ip6_blackhole_route,
174};
175
176static int __init xfrm6_policy_init(void)
177{
178 return xfrm_policy_register_afinfo(&xfrm6_policy_afinfo, AF_INET6);
179}
180
181static void xfrm6_policy_fini(void)
182{
183 xfrm_policy_unregister_afinfo(&xfrm6_policy_afinfo);
184}
185
186#ifdef CONFIG_SYSCTL
187static struct ctl_table xfrm6_policy_table[] = {
188 {
189 .procname = "xfrm6_gc_thresh",
190 .data = &init_net.xfrm.xfrm6_dst_ops.gc_thresh,
191 .maxlen = sizeof(int),
192 .mode = 0644,
193 .proc_handler = proc_dointvec,
194 },
195 { }
196};
197
198static int __net_init xfrm6_net_sysctl_init(struct net *net)
199{
200 struct ctl_table *table;
201 struct ctl_table_header *hdr;
202
203 table = xfrm6_policy_table;
204 if (!net_eq(net, &init_net)) {
205 table = kmemdup(table, sizeof(xfrm6_policy_table), GFP_KERNEL);
206 if (!table)
207 goto err_alloc;
208
209 table[0].data = &net->xfrm.xfrm6_dst_ops.gc_thresh;
210 }
211
212 hdr = register_net_sysctl(net, "net/ipv6", table);
213 if (!hdr)
214 goto err_reg;
215
216 net->ipv6.sysctl.xfrm6_hdr = hdr;
217 return 0;
218
219err_reg:
220 if (!net_eq(net, &init_net))
221 kfree(table);
222err_alloc:
223 return -ENOMEM;
224}
225
226static void __net_exit xfrm6_net_sysctl_exit(struct net *net)
227{
228 struct ctl_table *table;
229
230 if (!net->ipv6.sysctl.xfrm6_hdr)
231 return;
232
233 table = net->ipv6.sysctl.xfrm6_hdr->ctl_table_arg;
234 unregister_net_sysctl_table(net->ipv6.sysctl.xfrm6_hdr);
235 if (!net_eq(net, &init_net))
236 kfree(table);
237}
238#else /* CONFIG_SYSCTL */
239static inline int xfrm6_net_sysctl_init(struct net *net)
240{
241 return 0;
242}
243
244static inline void xfrm6_net_sysctl_exit(struct net *net)
245{
246}
247#endif
248
249static int __net_init xfrm6_net_init(struct net *net)
250{
251 int ret;
252
253 memcpy(&net->xfrm.xfrm6_dst_ops, &xfrm6_dst_ops_template,
254 sizeof(xfrm6_dst_ops_template));
255 ret = dst_entries_init(&net->xfrm.xfrm6_dst_ops);
256 if (ret)
257 return ret;
258
259 ret = xfrm6_net_sysctl_init(net);
260 if (ret)
261 dst_entries_destroy(&net->xfrm.xfrm6_dst_ops);
262
263 return ret;
264}
265
266static void __net_exit xfrm6_net_exit(struct net *net)
267{
268 xfrm6_net_sysctl_exit(net);
269 dst_entries_destroy(&net->xfrm.xfrm6_dst_ops);
270}
271
272static struct pernet_operations xfrm6_net_ops = {
273 .init = xfrm6_net_init,
274 .exit = xfrm6_net_exit,
275};
276
277int __init xfrm6_init(void)
278{
279 int ret;
280
281 ret = xfrm6_policy_init();
282 if (ret)
283 goto out;
284 ret = xfrm6_state_init();
285 if (ret)
286 goto out_policy;
287
288 ret = xfrm6_protocol_init();
289 if (ret)
290 goto out_state;
291
292 register_pernet_subsys(&xfrm6_net_ops);
293out:
294 return ret;
295out_state:
296 xfrm6_state_fini();
297out_policy:
298 xfrm6_policy_fini();
299 goto out;
300}
301
302void xfrm6_fini(void)
303{
304 unregister_pernet_subsys(&xfrm6_net_ops);
305 xfrm6_protocol_fini();
306 xfrm6_policy_fini();
307 xfrm6_state_fini();
308}