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 return (f6i->fib6_flags & (RTF_GATEWAY|RTF_ADDRCONF|RTF_DYNAMIC)) == 72 RTF_GATEWAY; 73 } 74 75 void ip6_route_input(struct sk_buff *skb); 76 struct dst_entry *ip6_route_input_lookup(struct net *net, 77 struct net_device *dev, 78 struct flowi6 *fl6, 79 const struct sk_buff *skb, int flags); 80 81 struct dst_entry *ip6_route_output_flags(struct net *net, const struct sock *sk, 82 struct flowi6 *fl6, int flags); 83 84 static inline struct dst_entry *ip6_route_output(struct net *net, 85 const struct sock *sk, 86 struct flowi6 *fl6) 87 { 88 return ip6_route_output_flags(net, sk, fl6, 0); 89 } 90 91 struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6, 92 const struct sk_buff *skb, int flags); 93 struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table, 94 int ifindex, struct flowi6 *fl6, 95 const struct sk_buff *skb, int flags); 96 97 void ip6_route_init_special_entries(void); 98 int ip6_route_init(void); 99 void ip6_route_cleanup(void); 100 101 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg); 102 103 int ip6_route_add(struct fib6_config *cfg, gfp_t gfp_flags, 104 struct netlink_ext_ack *extack); 105 int ip6_ins_rt(struct net *net, struct fib6_info *f6i); 106 int ip6_del_rt(struct net *net, struct fib6_info *f6i); 107 108 void rt6_flush_exceptions(struct fib6_info *f6i); 109 void rt6_age_exceptions(struct fib6_info *f6i, struct fib6_gc_args *gc_args, 110 unsigned long now); 111 112 static inline int ip6_route_get_saddr(struct net *net, struct fib6_info *f6i, 113 const struct in6_addr *daddr, 114 unsigned int prefs, 115 struct in6_addr *saddr) 116 { 117 int err = 0; 118 119 if (f6i && f6i->fib6_prefsrc.plen) { 120 *saddr = f6i->fib6_prefsrc.addr; 121 } else { 122 struct net_device *dev = f6i ? fib6_info_nh_dev(f6i) : NULL; 123 124 err = ipv6_dev_get_saddr(net, dev, daddr, prefs, saddr); 125 } 126 127 return err; 128 } 129 130 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr, 131 const struct in6_addr *saddr, int oif, 132 const struct sk_buff *skb, int flags); 133 u32 rt6_multipath_hash(const struct net *net, const struct flowi6 *fl6, 134 const struct sk_buff *skb, struct flow_keys *hkeys); 135 136 struct dst_entry *icmp6_dst_alloc(struct net_device *dev, struct flowi6 *fl6); 137 138 void fib6_force_start_gc(struct net *net); 139 140 struct fib6_info *addrconf_f6i_alloc(struct net *net, struct inet6_dev *idev, 141 const struct in6_addr *addr, bool anycast, 142 gfp_t gfp_flags); 143 144 struct rt6_info *ip6_dst_alloc(struct net *net, struct net_device *dev, 145 int flags); 146 147 /* 148 * support functions for ND 149 * 150 */ 151 struct fib6_info *rt6_get_dflt_router(struct net *net, 152 const struct in6_addr *addr, 153 struct net_device *dev); 154 struct fib6_info *rt6_add_dflt_router(struct net *net, 155 const struct in6_addr *gwaddr, 156 struct net_device *dev, unsigned int pref); 157 158 void rt6_purge_dflt_routers(struct net *net); 159 160 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len, 161 const struct in6_addr *gwaddr); 162 163 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu, int oif, 164 u32 mark, kuid_t uid); 165 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu); 166 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark, 167 kuid_t uid); 168 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif, 169 u32 mark); 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 }; 179 180 int rt6_dump_route(struct fib6_info *f6i, void *p_arg); 181 void rt6_mtu_change(struct net_device *dev, unsigned int mtu); 182 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp); 183 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway); 184 void rt6_sync_up(struct net_device *dev, unsigned int nh_flags); 185 void rt6_disable_ip(struct net_device *dev, unsigned long event); 186 void rt6_sync_down_dev(struct net_device *dev, unsigned long event); 187 void rt6_multipath_rebalance(struct fib6_info *f6i); 188 189 void rt6_uncached_list_add(struct rt6_info *rt); 190 void rt6_uncached_list_del(struct rt6_info *rt); 191 192 static inline const struct rt6_info *skb_rt6_info(const struct sk_buff *skb) 193 { 194 const struct dst_entry *dst = skb_dst(skb); 195 const struct rt6_info *rt6 = NULL; 196 197 if (dst) 198 rt6 = container_of(dst, struct rt6_info, dst); 199 200 return rt6; 201 } 202 203 /* 204 * Store a destination cache entry in a socket 205 */ 206 static inline void ip6_dst_store(struct sock *sk, struct dst_entry *dst, 207 const struct in6_addr *daddr, 208 const struct in6_addr *saddr) 209 { 210 struct ipv6_pinfo *np = inet6_sk(sk); 211 212 np->dst_cookie = rt6_get_cookie((struct rt6_info *)dst); 213 sk_setup_caps(sk, dst); 214 np->daddr_cache = daddr; 215 #ifdef CONFIG_IPV6_SUBTREES 216 np->saddr_cache = saddr; 217 #endif 218 } 219 220 void ip6_sk_dst_store_flow(struct sock *sk, struct dst_entry *dst, 221 const struct flowi6 *fl6); 222 223 static inline bool ipv6_unicast_destination(const struct sk_buff *skb) 224 { 225 struct rt6_info *rt = (struct rt6_info *) skb_dst(skb); 226 227 return rt->rt6i_flags & RTF_LOCAL; 228 } 229 230 static inline bool ipv6_anycast_destination(const struct dst_entry *dst, 231 const struct in6_addr *daddr) 232 { 233 struct rt6_info *rt = (struct rt6_info *)dst; 234 235 return rt->rt6i_flags & RTF_ANYCAST || 236 (rt->rt6i_dst.plen < 127 && 237 ipv6_addr_equal(&rt->rt6i_dst.addr, daddr)); 238 } 239 240 int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb, 241 int (*output)(struct net *, struct sock *, struct sk_buff *)); 242 243 static inline int ip6_skb_dst_mtu(struct sk_buff *skb) 244 { 245 struct ipv6_pinfo *np = skb->sk && !dev_recursion_level() ? 246 inet6_sk(skb->sk) : NULL; 247 248 return (np && np->pmtudisc >= IPV6_PMTUDISC_PROBE) ? 249 skb_dst(skb)->dev->mtu : dst_mtu(skb_dst(skb)); 250 } 251 252 static inline bool ip6_sk_accept_pmtu(const struct sock *sk) 253 { 254 return inet6_sk(sk)->pmtudisc != IPV6_PMTUDISC_INTERFACE && 255 inet6_sk(sk)->pmtudisc != IPV6_PMTUDISC_OMIT; 256 } 257 258 static inline bool ip6_sk_ignore_df(const struct sock *sk) 259 { 260 return inet6_sk(sk)->pmtudisc < IPV6_PMTUDISC_DO || 261 inet6_sk(sk)->pmtudisc == IPV6_PMTUDISC_OMIT; 262 } 263 264 static inline struct in6_addr *rt6_nexthop(struct rt6_info *rt, 265 struct in6_addr *daddr) 266 { 267 if (rt->rt6i_flags & RTF_GATEWAY) 268 return &rt->rt6i_gateway; 269 else if (unlikely(rt->rt6i_flags & RTF_CACHE)) 270 return &rt->rt6i_dst.addr; 271 else 272 return daddr; 273 } 274 275 static inline bool rt6_duplicate_nexthop(struct fib6_info *a, struct fib6_info *b) 276 { 277 return a->fib6_nh.nh_dev == b->fib6_nh.nh_dev && 278 ipv6_addr_equal(&a->fib6_nh.nh_gw, &b->fib6_nh.nh_gw) && 279 !lwtunnel_cmp_encap(a->fib6_nh.nh_lwtstate, b->fib6_nh.nh_lwtstate); 280 } 281 282 static inline unsigned int ip6_dst_mtu_forward(const struct dst_entry *dst) 283 { 284 struct inet6_dev *idev; 285 unsigned int mtu; 286 287 if (dst_metric_locked(dst, RTAX_MTU)) { 288 mtu = dst_metric_raw(dst, RTAX_MTU); 289 if (mtu) 290 return mtu; 291 } 292 293 mtu = IPV6_MIN_MTU; 294 rcu_read_lock(); 295 idev = __in6_dev_get(dst->dev); 296 if (idev) 297 mtu = idev->cnf.mtu6; 298 rcu_read_unlock(); 299 300 return mtu; 301 } 302 303 u32 ip6_mtu_from_fib6(struct fib6_info *f6i, struct in6_addr *daddr, 304 struct in6_addr *saddr); 305 306 struct neighbour *ip6_neigh_lookup(const struct in6_addr *gw, 307 struct net_device *dev, struct sk_buff *skb, 308 const void *daddr); 309 #endif 310