1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _NET_IP6_ROUTE_H 3 #define _NET_IP6_ROUTE_H 4 5 struct route_info { 6 __u8 type; 7 __u8 length; 8 __u8 prefix_len; 9 #if defined(__BIG_ENDIAN_BITFIELD) 10 __u8 reserved_h:3, 11 route_pref:2, 12 reserved_l:3; 13 #elif defined(__LITTLE_ENDIAN_BITFIELD) 14 __u8 reserved_l:3, 15 route_pref:2, 16 reserved_h:3; 17 #endif 18 __be32 lifetime; 19 __u8 prefix[0]; /* 0,8 or 16 */ 20 }; 21 22 #include <net/addrconf.h> 23 #include <net/flow.h> 24 #include <net/ip6_fib.h> 25 #include <net/sock.h> 26 #include <net/lwtunnel.h> 27 #include <linux/ip.h> 28 #include <linux/ipv6.h> 29 #include <linux/route.h> 30 31 #define RT6_LOOKUP_F_IFACE 0x00000001 32 #define RT6_LOOKUP_F_REACHABLE 0x00000002 33 #define RT6_LOOKUP_F_HAS_SADDR 0x00000004 34 #define RT6_LOOKUP_F_SRCPREF_TMP 0x00000008 35 #define RT6_LOOKUP_F_SRCPREF_PUBLIC 0x00000010 36 #define RT6_LOOKUP_F_SRCPREF_COA 0x00000020 37 #define RT6_LOOKUP_F_IGNORE_LINKSTATE 0x00000040 38 39 /* We do not (yet ?) support IPv6 jumbograms (RFC 2675) 40 * Unlike IPv4, hdr->seg_len doesn't include the IPv6 header 41 */ 42 #define IP6_MAX_MTU (0xFFFF + sizeof(struct ipv6hdr)) 43 44 /* 45 * rt6_srcprefs2flags() and rt6_flags2srcprefs() translate 46 * between IPV6_ADDR_PREFERENCES socket option values 47 * IPV6_PREFER_SRC_TMP = 0x1 48 * IPV6_PREFER_SRC_PUBLIC = 0x2 49 * IPV6_PREFER_SRC_COA = 0x4 50 * and above RT6_LOOKUP_F_SRCPREF_xxx flags. 51 */ 52 static inline int rt6_srcprefs2flags(unsigned int srcprefs) 53 { 54 /* No need to bitmask because srcprefs have only 3 bits. */ 55 return srcprefs << 3; 56 } 57 58 static inline unsigned int rt6_flags2srcprefs(int flags) 59 { 60 return (flags >> 3) & 7; 61 } 62 63 static inline bool rt6_need_strict(const struct in6_addr *daddr) 64 { 65 return ipv6_addr_type(daddr) & 66 (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK); 67 } 68 69 static inline bool rt6_qualify_for_ecmp(const struct fib6_info *f6i) 70 { 71 /* the RTF_ADDRCONF flag filters out RA's */ 72 return !(f6i->fib6_flags & RTF_ADDRCONF) && 73 f6i->fib6_nh.fib_nh_gw_family; 74 } 75 76 void ip6_route_input(struct sk_buff *skb); 77 struct dst_entry *ip6_route_input_lookup(struct net *net, 78 struct net_device *dev, 79 struct flowi6 *fl6, 80 const struct sk_buff *skb, int flags); 81 82 struct dst_entry *ip6_route_output_flags(struct net *net, const struct sock *sk, 83 struct flowi6 *fl6, int flags); 84 85 static inline struct dst_entry *ip6_route_output(struct net *net, 86 const struct sock *sk, 87 struct flowi6 *fl6) 88 { 89 return ip6_route_output_flags(net, sk, fl6, 0); 90 } 91 92 struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6, 93 const struct sk_buff *skb, int flags); 94 struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table, 95 int ifindex, struct flowi6 *fl6, 96 const struct sk_buff *skb, int flags); 97 98 void ip6_route_init_special_entries(void); 99 int ip6_route_init(void); 100 void ip6_route_cleanup(void); 101 102 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg); 103 104 int ip6_route_add(struct fib6_config *cfg, gfp_t gfp_flags, 105 struct netlink_ext_ack *extack); 106 int ip6_ins_rt(struct net *net, struct fib6_info *f6i); 107 int ip6_del_rt(struct net *net, struct fib6_info *f6i); 108 109 void rt6_flush_exceptions(struct fib6_info *f6i); 110 void rt6_age_exceptions(struct fib6_info *f6i, struct fib6_gc_args *gc_args, 111 unsigned long now); 112 113 static inline int ip6_route_get_saddr(struct net *net, struct fib6_info *f6i, 114 const struct in6_addr *daddr, 115 unsigned int prefs, 116 struct in6_addr *saddr) 117 { 118 int err = 0; 119 120 if (f6i && f6i->fib6_prefsrc.plen) { 121 *saddr = f6i->fib6_prefsrc.addr; 122 } else { 123 struct net_device *dev = f6i ? fib6_info_nh_dev(f6i) : NULL; 124 125 err = ipv6_dev_get_saddr(net, dev, daddr, prefs, saddr); 126 } 127 128 return err; 129 } 130 131 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr, 132 const struct in6_addr *saddr, int oif, 133 const struct sk_buff *skb, int flags); 134 u32 rt6_multipath_hash(const struct net *net, const struct flowi6 *fl6, 135 const struct sk_buff *skb, struct flow_keys *hkeys); 136 137 struct dst_entry *icmp6_dst_alloc(struct net_device *dev, struct flowi6 *fl6); 138 139 void fib6_force_start_gc(struct net *net); 140 141 struct fib6_info *addrconf_f6i_alloc(struct net *net, struct inet6_dev *idev, 142 const struct in6_addr *addr, bool anycast, 143 gfp_t gfp_flags); 144 145 struct rt6_info *ip6_dst_alloc(struct net *net, struct net_device *dev, 146 int flags); 147 148 /* 149 * support functions for ND 150 * 151 */ 152 struct fib6_info *rt6_get_dflt_router(struct net *net, 153 const struct in6_addr *addr, 154 struct net_device *dev); 155 struct fib6_info *rt6_add_dflt_router(struct net *net, 156 const struct in6_addr *gwaddr, 157 struct net_device *dev, unsigned int pref); 158 159 void rt6_purge_dflt_routers(struct net *net); 160 161 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len, 162 const struct in6_addr *gwaddr); 163 164 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu, int oif, 165 u32 mark, kuid_t uid); 166 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu); 167 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark, 168 kuid_t uid); 169 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif); 170 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk); 171 172 struct netlink_callback; 173 174 struct rt6_rtnl_dump_arg { 175 struct sk_buff *skb; 176 struct netlink_callback *cb; 177 struct net *net; 178 struct fib_dump_filter filter; 179 }; 180 181 int rt6_dump_route(struct fib6_info *f6i, void *p_arg); 182 void rt6_mtu_change(struct net_device *dev, unsigned int mtu); 183 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp); 184 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway); 185 void rt6_sync_up(struct net_device *dev, unsigned char nh_flags); 186 void rt6_disable_ip(struct net_device *dev, unsigned long event); 187 void rt6_sync_down_dev(struct net_device *dev, unsigned long event); 188 void rt6_multipath_rebalance(struct fib6_info *f6i); 189 190 void rt6_uncached_list_add(struct rt6_info *rt); 191 void rt6_uncached_list_del(struct rt6_info *rt); 192 193 static inline const struct rt6_info *skb_rt6_info(const struct sk_buff *skb) 194 { 195 const struct dst_entry *dst = skb_dst(skb); 196 const struct rt6_info *rt6 = NULL; 197 198 if (dst) 199 rt6 = container_of(dst, struct rt6_info, dst); 200 201 return rt6; 202 } 203 204 /* 205 * Store a destination cache entry in a socket 206 */ 207 static inline void ip6_dst_store(struct sock *sk, struct dst_entry *dst, 208 const struct in6_addr *daddr, 209 const struct in6_addr *saddr) 210 { 211 struct ipv6_pinfo *np = inet6_sk(sk); 212 213 np->dst_cookie = rt6_get_cookie((struct rt6_info *)dst); 214 sk_setup_caps(sk, dst); 215 np->daddr_cache = daddr; 216 #ifdef CONFIG_IPV6_SUBTREES 217 np->saddr_cache = saddr; 218 #endif 219 } 220 221 void ip6_sk_dst_store_flow(struct sock *sk, struct dst_entry *dst, 222 const struct flowi6 *fl6); 223 224 static inline bool ipv6_unicast_destination(const struct sk_buff *skb) 225 { 226 struct rt6_info *rt = (struct rt6_info *) skb_dst(skb); 227 228 return rt->rt6i_flags & RTF_LOCAL; 229 } 230 231 static inline bool ipv6_anycast_destination(const struct dst_entry *dst, 232 const struct in6_addr *daddr) 233 { 234 struct rt6_info *rt = (struct rt6_info *)dst; 235 236 return rt->rt6i_flags & RTF_ANYCAST || 237 (rt->rt6i_dst.plen < 127 && 238 ipv6_addr_equal(&rt->rt6i_dst.addr, daddr)); 239 } 240 241 int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb, 242 int (*output)(struct net *, struct sock *, struct sk_buff *)); 243 244 static inline int ip6_skb_dst_mtu(struct sk_buff *skb) 245 { 246 struct ipv6_pinfo *np = skb->sk && !dev_recursion_level() ? 247 inet6_sk(skb->sk) : NULL; 248 249 return (np && np->pmtudisc >= IPV6_PMTUDISC_PROBE) ? 250 skb_dst(skb)->dev->mtu : dst_mtu(skb_dst(skb)); 251 } 252 253 static inline bool ip6_sk_accept_pmtu(const struct sock *sk) 254 { 255 return inet6_sk(sk)->pmtudisc != IPV6_PMTUDISC_INTERFACE && 256 inet6_sk(sk)->pmtudisc != IPV6_PMTUDISC_OMIT; 257 } 258 259 static inline bool ip6_sk_ignore_df(const struct sock *sk) 260 { 261 return inet6_sk(sk)->pmtudisc < IPV6_PMTUDISC_DO || 262 inet6_sk(sk)->pmtudisc == IPV6_PMTUDISC_OMIT; 263 } 264 265 static inline struct in6_addr *rt6_nexthop(struct rt6_info *rt, 266 struct in6_addr *daddr) 267 { 268 if (rt->rt6i_flags & RTF_GATEWAY) 269 return &rt->rt6i_gateway; 270 else if (unlikely(rt->rt6i_flags & RTF_CACHE)) 271 return &rt->rt6i_dst.addr; 272 else 273 return daddr; 274 } 275 276 static inline bool rt6_duplicate_nexthop(struct fib6_info *a, struct fib6_info *b) 277 { 278 struct fib6_nh *nha = &a->fib6_nh, *nhb = &b->fib6_nh; 279 280 return nha->fib_nh_dev == nhb->fib_nh_dev && 281 ipv6_addr_equal(&nha->fib_nh_gw6, &nhb->fib_nh_gw6) && 282 !lwtunnel_cmp_encap(nha->fib_nh_lws, nhb->fib_nh_lws); 283 } 284 285 static inline unsigned int ip6_dst_mtu_forward(const struct dst_entry *dst) 286 { 287 struct inet6_dev *idev; 288 unsigned int mtu; 289 290 if (dst_metric_locked(dst, RTAX_MTU)) { 291 mtu = dst_metric_raw(dst, RTAX_MTU); 292 if (mtu) 293 return mtu; 294 } 295 296 mtu = IPV6_MIN_MTU; 297 rcu_read_lock(); 298 idev = __in6_dev_get(dst->dev); 299 if (idev) 300 mtu = idev->cnf.mtu6; 301 rcu_read_unlock(); 302 303 return mtu; 304 } 305 306 u32 ip6_mtu_from_fib6(const struct fib6_result *res, 307 const struct in6_addr *daddr, 308 const struct in6_addr *saddr); 309 310 struct neighbour *ip6_neigh_lookup(const struct in6_addr *gw, 311 struct net_device *dev, struct sk_buff *skb, 312 const void *daddr); 313 #endif 314