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 rt6_info *rt) 70 { 71 return (rt->rt6i_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, struct netlink_ext_ack *extack); 104 int ip6_ins_rt(struct rt6_info *); 105 int ip6_del_rt(struct rt6_info *); 106 107 void rt6_flush_exceptions(struct rt6_info *rt); 108 int rt6_remove_exception_rt(struct rt6_info *rt); 109 void rt6_age_exceptions(struct rt6_info *rt, struct fib6_gc_args *gc_args, 110 unsigned long now); 111 112 static inline int ip6_route_get_saddr(struct net *net, struct rt6_info *rt, 113 const struct in6_addr *daddr, 114 unsigned int prefs, 115 struct in6_addr *saddr) 116 { 117 struct inet6_dev *idev = 118 rt ? ip6_dst_idev((struct dst_entry *)rt) : NULL; 119 int err = 0; 120 121 if (rt && rt->rt6i_prefsrc.plen) 122 *saddr = rt->rt6i_prefsrc.addr; 123 else 124 err = ipv6_dev_get_saddr(net, idev ? idev->dev : NULL, 125 daddr, prefs, saddr); 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 rt6_info *addrconf_dst_alloc(struct inet6_dev *idev, 141 const struct in6_addr *addr, bool anycast); 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 rt6_info *rt6_get_dflt_router(const struct in6_addr *addr, 151 struct net_device *dev); 152 struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr, 153 struct net_device *dev, unsigned int pref); 154 155 void rt6_purge_dflt_routers(struct net *net); 156 157 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len, 158 const struct in6_addr *gwaddr); 159 160 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu, int oif, 161 u32 mark, kuid_t uid); 162 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu); 163 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark, 164 kuid_t uid); 165 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif, 166 u32 mark); 167 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk); 168 169 struct netlink_callback; 170 171 struct rt6_rtnl_dump_arg { 172 struct sk_buff *skb; 173 struct netlink_callback *cb; 174 struct net *net; 175 }; 176 177 int rt6_dump_route(struct rt6_info *rt, void *p_arg); 178 void rt6_mtu_change(struct net_device *dev, unsigned int mtu); 179 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp); 180 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway); 181 void rt6_sync_up(struct net_device *dev, unsigned int nh_flags); 182 void rt6_disable_ip(struct net_device *dev, unsigned long event); 183 void rt6_sync_down_dev(struct net_device *dev, unsigned long event); 184 void rt6_multipath_rebalance(struct rt6_info *rt); 185 186 void rt6_uncached_list_add(struct rt6_info *rt); 187 void rt6_uncached_list_del(struct rt6_info *rt); 188 189 static inline const struct rt6_info *skb_rt6_info(const struct sk_buff *skb) 190 { 191 const struct dst_entry *dst = skb_dst(skb); 192 const struct rt6_info *rt6 = NULL; 193 194 if (dst) 195 rt6 = container_of(dst, struct rt6_info, dst); 196 197 return rt6; 198 } 199 200 /* 201 * Store a destination cache entry in a socket 202 */ 203 static inline void ip6_dst_store(struct sock *sk, struct dst_entry *dst, 204 const struct in6_addr *daddr, 205 const struct in6_addr *saddr) 206 { 207 struct ipv6_pinfo *np = inet6_sk(sk); 208 209 np->dst_cookie = rt6_get_cookie((struct rt6_info *)dst); 210 sk_setup_caps(sk, dst); 211 np->daddr_cache = daddr; 212 #ifdef CONFIG_IPV6_SUBTREES 213 np->saddr_cache = saddr; 214 #endif 215 } 216 217 void ip6_sk_dst_store_flow(struct sock *sk, struct dst_entry *dst, 218 const struct flowi6 *fl6); 219 220 static inline bool ipv6_unicast_destination(const struct sk_buff *skb) 221 { 222 struct rt6_info *rt = (struct rt6_info *) skb_dst(skb); 223 224 return rt->rt6i_flags & RTF_LOCAL; 225 } 226 227 static inline bool ipv6_anycast_destination(const struct dst_entry *dst, 228 const struct in6_addr *daddr) 229 { 230 struct rt6_info *rt = (struct rt6_info *)dst; 231 232 return rt->rt6i_flags & RTF_ANYCAST || 233 (rt->rt6i_dst.plen < 127 && 234 ipv6_addr_equal(&rt->rt6i_dst.addr, daddr)); 235 } 236 237 int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb, 238 int (*output)(struct net *, struct sock *, struct sk_buff *)); 239 240 static inline int ip6_skb_dst_mtu(struct sk_buff *skb) 241 { 242 struct ipv6_pinfo *np = skb->sk && !dev_recursion_level() ? 243 inet6_sk(skb->sk) : NULL; 244 245 return (np && np->pmtudisc >= IPV6_PMTUDISC_PROBE) ? 246 skb_dst(skb)->dev->mtu : dst_mtu(skb_dst(skb)); 247 } 248 249 static inline bool ip6_sk_accept_pmtu(const struct sock *sk) 250 { 251 return inet6_sk(sk)->pmtudisc != IPV6_PMTUDISC_INTERFACE && 252 inet6_sk(sk)->pmtudisc != IPV6_PMTUDISC_OMIT; 253 } 254 255 static inline bool ip6_sk_ignore_df(const struct sock *sk) 256 { 257 return inet6_sk(sk)->pmtudisc < IPV6_PMTUDISC_DO || 258 inet6_sk(sk)->pmtudisc == IPV6_PMTUDISC_OMIT; 259 } 260 261 static inline struct in6_addr *rt6_nexthop(struct rt6_info *rt, 262 struct in6_addr *daddr) 263 { 264 if (rt->rt6i_flags & RTF_GATEWAY) 265 return &rt->rt6i_gateway; 266 else if (unlikely(rt->rt6i_flags & RTF_CACHE)) 267 return &rt->rt6i_dst.addr; 268 else 269 return daddr; 270 } 271 272 static inline bool rt6_duplicate_nexthop(struct rt6_info *a, struct rt6_info *b) 273 { 274 return a->dst.dev == b->dst.dev && 275 a->rt6i_idev == b->rt6i_idev && 276 ipv6_addr_equal(&a->rt6i_gateway, &b->rt6i_gateway) && 277 !lwtunnel_cmp_encap(a->dst.lwtstate, b->dst.lwtstate); 278 } 279 280 #endif 281