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 26 static struct dst_entry *xfrm6_dst_lookup(const struct xfrm_dst_lookup_params *params) 27 { 28 struct flowi6 fl6; 29 struct dst_entry *dst; 30 int err; 31 32 memset(&fl6, 0, sizeof(fl6)); 33 fl6.flowi6_l3mdev = l3mdev_master_ifindex_by_index(params->net, 34 params->oif); 35 fl6.flowi6_mark = params->mark; 36 memcpy(&fl6.daddr, params->daddr, sizeof(fl6.daddr)); 37 if (params->saddr) 38 memcpy(&fl6.saddr, params->saddr, sizeof(fl6.saddr)); 39 40 fl6.flowi4_proto = params->ipproto; 41 fl6.uli = params->uli; 42 43 dst = ip6_route_output(params->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 54 static int xfrm6_get_saddr(xfrm_address_t *saddr, 55 const struct xfrm_dst_lookup_params *params) 56 { 57 struct dst_entry *dst; 58 struct net_device *dev; 59 struct inet6_dev *idev; 60 61 dst = xfrm6_dst_lookup(params); 62 if (IS_ERR(dst)) 63 return -EHOSTUNREACH; 64 65 idev = ip6_dst_idev(dst); 66 if (!idev) { 67 dst_release(dst); 68 return -EHOSTUNREACH; 69 } 70 dev = idev->dev; 71 ipv6_dev_get_saddr(dev_net(dev), dev, ¶ms->daddr->in6, 0, 72 &saddr->in6); 73 dst_release(dst); 74 return 0; 75 } 76 77 static int xfrm6_fill_dst(struct xfrm_dst *xdst, struct net_device *dev, 78 const struct flowi *fl) 79 { 80 struct rt6_info *rt = (struct rt6_info *)xdst->route; 81 82 xdst->u.dst.dev = dev; 83 netdev_hold(dev, &xdst->u.dst.dev_tracker, GFP_ATOMIC); 84 85 xdst->u.rt6.rt6i_idev = in6_dev_get(dev); 86 if (!xdst->u.rt6.rt6i_idev) { 87 netdev_put(dev, &xdst->u.dst.dev_tracker); 88 return -ENODEV; 89 } 90 91 /* Sheit... I remember I did this right. Apparently, 92 * it was magically lost, so this code needs audit */ 93 xdst->u.rt6.rt6i_flags = rt->rt6i_flags & (RTF_ANYCAST | 94 RTF_LOCAL); 95 xdst->route_cookie = rt6_get_cookie(rt); 96 xdst->u.rt6.rt6i_gateway = rt->rt6i_gateway; 97 xdst->u.rt6.rt6i_dst = rt->rt6i_dst; 98 xdst->u.rt6.rt6i_src = rt->rt6i_src; 99 rt6_uncached_list_add(&xdst->u.rt6); 100 101 return 0; 102 } 103 104 static void xfrm6_update_pmtu(struct dst_entry *dst, struct sock *sk, 105 struct sk_buff *skb, u32 mtu, 106 bool confirm_neigh) 107 { 108 struct xfrm_dst *xdst = (struct xfrm_dst *)dst; 109 struct dst_entry *path = xdst->route; 110 111 path->ops->update_pmtu(path, sk, skb, mtu, confirm_neigh); 112 } 113 114 static void xfrm6_redirect(struct dst_entry *dst, struct sock *sk, 115 struct sk_buff *skb) 116 { 117 struct xfrm_dst *xdst = (struct xfrm_dst *)dst; 118 struct dst_entry *path = xdst->route; 119 120 path->ops->redirect(path, sk, skb); 121 } 122 123 static void xfrm6_dst_destroy(struct dst_entry *dst) 124 { 125 struct xfrm_dst *xdst = (struct xfrm_dst *)dst; 126 127 dst_destroy_metrics_generic(dst); 128 rt6_uncached_list_del(&xdst->u.rt6); 129 if (likely(xdst->u.rt6.rt6i_idev)) 130 in6_dev_put(xdst->u.rt6.rt6i_idev); 131 xfrm_dst_destroy(xdst); 132 } 133 134 static void xfrm6_dst_ifdown(struct dst_entry *dst, struct net_device *dev) 135 { 136 struct xfrm_dst *xdst; 137 138 xdst = (struct xfrm_dst *)dst; 139 if (xdst->u.rt6.rt6i_idev->dev == dev) { 140 struct inet6_dev *loopback_idev = 141 in6_dev_get(dev_net(dev)->loopback_dev); 142 143 do { 144 in6_dev_put(xdst->u.rt6.rt6i_idev); 145 xdst->u.rt6.rt6i_idev = loopback_idev; 146 in6_dev_hold(loopback_idev); 147 xdst = (struct xfrm_dst *)xfrm_dst_child(&xdst->u.dst); 148 } while (xdst->u.dst.xfrm); 149 150 __in6_dev_put(loopback_idev); 151 } 152 153 xfrm_dst_ifdown(dst, dev); 154 } 155 156 static struct dst_ops xfrm6_dst_ops_template = { 157 .family = AF_INET6, 158 .update_pmtu = xfrm6_update_pmtu, 159 .redirect = xfrm6_redirect, 160 .cow_metrics = dst_cow_metrics_generic, 161 .destroy = xfrm6_dst_destroy, 162 .ifdown = xfrm6_dst_ifdown, 163 .local_out = __ip6_local_out, 164 .gc_thresh = 32768, 165 }; 166 167 static const struct xfrm_policy_afinfo xfrm6_policy_afinfo = { 168 .dst_ops = &xfrm6_dst_ops_template, 169 .dst_lookup = xfrm6_dst_lookup, 170 .get_saddr = xfrm6_get_saddr, 171 .fill_dst = xfrm6_fill_dst, 172 .blackhole_route = ip6_blackhole_route, 173 }; 174 175 static int __init xfrm6_policy_init(void) 176 { 177 return xfrm_policy_register_afinfo(&xfrm6_policy_afinfo, AF_INET6); 178 } 179 180 static void xfrm6_policy_fini(void) 181 { 182 xfrm_policy_unregister_afinfo(&xfrm6_policy_afinfo); 183 } 184 185 #ifdef CONFIG_SYSCTL 186 static struct ctl_table xfrm6_policy_table[] = { 187 { 188 .procname = "xfrm6_gc_thresh", 189 .data = &init_net.xfrm.xfrm6_dst_ops.gc_thresh, 190 .maxlen = sizeof(int), 191 .mode = 0644, 192 .proc_handler = proc_dointvec, 193 }, 194 { } 195 }; 196 197 static int __net_init xfrm6_net_sysctl_init(struct net *net) 198 { 199 struct ctl_table *table; 200 struct ctl_table_header *hdr; 201 202 table = xfrm6_policy_table; 203 if (!net_eq(net, &init_net)) { 204 table = kmemdup(table, sizeof(xfrm6_policy_table), GFP_KERNEL); 205 if (!table) 206 goto err_alloc; 207 208 table[0].data = &net->xfrm.xfrm6_dst_ops.gc_thresh; 209 } 210 211 hdr = register_net_sysctl_sz(net, "net/ipv6", table, 212 ARRAY_SIZE(xfrm6_policy_table)); 213 if (!hdr) 214 goto err_reg; 215 216 net->ipv6.sysctl.xfrm6_hdr = hdr; 217 return 0; 218 219 err_reg: 220 if (!net_eq(net, &init_net)) 221 kfree(table); 222 err_alloc: 223 return -ENOMEM; 224 } 225 226 static 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 */ 239 static inline int xfrm6_net_sysctl_init(struct net *net) 240 { 241 return 0; 242 } 243 244 static inline void xfrm6_net_sysctl_exit(struct net *net) 245 { 246 } 247 #endif 248 249 static 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 } 265 266 static 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 } 271 272 static struct pernet_operations xfrm6_net_ops = { 273 .init = xfrm6_net_init, 274 .exit = xfrm6_net_exit, 275 }; 276 277 int __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 ret = register_pernet_subsys(&xfrm6_net_ops); 293 if (ret) 294 goto out_protocol; 295 out: 296 return ret; 297 out_protocol: 298 xfrm6_protocol_fini(); 299 out_state: 300 xfrm6_state_fini(); 301 out_policy: 302 xfrm6_policy_fini(); 303 goto out; 304 } 305 306 void xfrm6_fini(void) 307 { 308 unregister_pernet_subsys(&xfrm6_net_ops); 309 xfrm6_protocol_fini(); 310 xfrm6_policy_fini(); 311 xfrm6_state_fini(); 312 } 313