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 struct inet6_dev *idev = f6i ? f6i->fib6_idev : NULL; 118 int err = 0; 119 120 if (f6i && f6i->fib6_prefsrc.plen) 121 *saddr = f6i->fib6_prefsrc.addr; 122 else 123 err = ipv6_dev_get_saddr(net, idev ? idev->dev : NULL, 124 daddr, prefs, saddr); 125 126 return err; 127 } 128 129 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr, 130 const struct in6_addr *saddr, int oif, 131 const struct sk_buff *skb, int flags); 132 u32 rt6_multipath_hash(const struct net *net, const struct flowi6 *fl6, 133 const struct sk_buff *skb, struct flow_keys *hkeys); 134 135 struct dst_entry *icmp6_dst_alloc(struct net_device *dev, struct flowi6 *fl6); 136 137 void fib6_force_start_gc(struct net *net); 138 139 struct fib6_info *addrconf_f6i_alloc(struct net *net, struct inet6_dev *idev, 140 const struct in6_addr *addr, bool anycast, 141 gfp_t gfp_flags); 142 143 struct rt6_info *ip6_dst_alloc(struct net *net, struct net_device *dev, 144 int flags); 145 146 /* 147 * support functions for ND 148 * 149 */ 150 struct fib6_info *rt6_get_dflt_router(struct net *net, 151 const struct in6_addr *addr, 152 struct net_device *dev); 153 struct fib6_info *rt6_add_dflt_router(struct net *net, 154 const struct in6_addr *gwaddr, 155 struct net_device *dev, unsigned int pref); 156 157 void rt6_purge_dflt_routers(struct net *net); 158 159 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len, 160 const struct in6_addr *gwaddr); 161 162 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu, int oif, 163 u32 mark, kuid_t uid); 164 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu); 165 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark, 166 kuid_t uid); 167 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif, 168 u32 mark); 169 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk); 170 171 struct netlink_callback; 172 173 struct rt6_rtnl_dump_arg { 174 struct sk_buff *skb; 175 struct netlink_callback *cb; 176 struct net *net; 177 }; 178 179 int rt6_dump_route(struct fib6_info *f6i, void *p_arg); 180 void rt6_mtu_change(struct net_device *dev, unsigned int mtu); 181 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp); 182 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway); 183 void rt6_sync_up(struct net_device *dev, unsigned int nh_flags); 184 void rt6_disable_ip(struct net_device *dev, unsigned long event); 185 void rt6_sync_down_dev(struct net_device *dev, unsigned long event); 186 void rt6_multipath_rebalance(struct fib6_info *f6i); 187 188 void rt6_uncached_list_add(struct rt6_info *rt); 189 void rt6_uncached_list_del(struct rt6_info *rt); 190 191 static inline const struct rt6_info *skb_rt6_info(const struct sk_buff *skb) 192 { 193 const struct dst_entry *dst = skb_dst(skb); 194 const struct rt6_info *rt6 = NULL; 195 196 if (dst) 197 rt6 = container_of(dst, struct rt6_info, dst); 198 199 return rt6; 200 } 201 202 /* 203 * Store a destination cache entry in a socket 204 */ 205 static inline void ip6_dst_store(struct sock *sk, struct dst_entry *dst, 206 const struct in6_addr *daddr, 207 const struct in6_addr *saddr) 208 { 209 struct ipv6_pinfo *np = inet6_sk(sk); 210 211 np->dst_cookie = rt6_get_cookie((struct rt6_info *)dst); 212 sk_setup_caps(sk, dst); 213 np->daddr_cache = daddr; 214 #ifdef CONFIG_IPV6_SUBTREES 215 np->saddr_cache = saddr; 216 #endif 217 } 218 219 void ip6_sk_dst_store_flow(struct sock *sk, struct dst_entry *dst, 220 const struct flowi6 *fl6); 221 222 static inline bool ipv6_unicast_destination(const struct sk_buff *skb) 223 { 224 struct rt6_info *rt = (struct rt6_info *) skb_dst(skb); 225 226 return rt->rt6i_flags & RTF_LOCAL; 227 } 228 229 static inline bool ipv6_anycast_destination(const struct dst_entry *dst, 230 const struct in6_addr *daddr) 231 { 232 struct rt6_info *rt = (struct rt6_info *)dst; 233 234 return rt->rt6i_flags & RTF_ANYCAST || 235 (rt->rt6i_dst.plen < 127 && 236 ipv6_addr_equal(&rt->rt6i_dst.addr, daddr)); 237 } 238 239 int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb, 240 int (*output)(struct net *, struct sock *, struct sk_buff *)); 241 242 static inline int ip6_skb_dst_mtu(struct sk_buff *skb) 243 { 244 struct ipv6_pinfo *np = skb->sk && !dev_recursion_level() ? 245 inet6_sk(skb->sk) : NULL; 246 247 return (np && np->pmtudisc >= IPV6_PMTUDISC_PROBE) ? 248 skb_dst(skb)->dev->mtu : dst_mtu(skb_dst(skb)); 249 } 250 251 static inline bool ip6_sk_accept_pmtu(const struct sock *sk) 252 { 253 return inet6_sk(sk)->pmtudisc != IPV6_PMTUDISC_INTERFACE && 254 inet6_sk(sk)->pmtudisc != IPV6_PMTUDISC_OMIT; 255 } 256 257 static inline bool ip6_sk_ignore_df(const struct sock *sk) 258 { 259 return inet6_sk(sk)->pmtudisc < IPV6_PMTUDISC_DO || 260 inet6_sk(sk)->pmtudisc == IPV6_PMTUDISC_OMIT; 261 } 262 263 static inline struct in6_addr *rt6_nexthop(struct rt6_info *rt, 264 struct in6_addr *daddr) 265 { 266 if (rt->rt6i_flags & RTF_GATEWAY) 267 return &rt->rt6i_gateway; 268 else if (unlikely(rt->rt6i_flags & RTF_CACHE)) 269 return &rt->rt6i_dst.addr; 270 else 271 return daddr; 272 } 273 274 static inline bool rt6_duplicate_nexthop(struct fib6_info *a, struct fib6_info *b) 275 { 276 return a->fib6_nh.nh_dev == b->fib6_nh.nh_dev && 277 a->fib6_idev == b->fib6_idev && 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 struct neighbour *ip6_neigh_lookup(const struct in6_addr *gw, 283 struct net_device *dev, struct sk_buff *skb, 284 const void *daddr); 285 #endif 286