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, int flags); 79 80 struct dst_entry *ip6_route_output_flags(struct net *net, const struct sock *sk, 81 struct flowi6 *fl6, int flags); 82 83 static inline struct dst_entry *ip6_route_output(struct net *net, 84 const struct sock *sk, 85 struct flowi6 *fl6) 86 { 87 return ip6_route_output_flags(net, sk, fl6, 0); 88 } 89 90 struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6, 91 int flags); 92 struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table, 93 int ifindex, struct flowi6 *fl6, int flags); 94 95 void ip6_route_init_special_entries(void); 96 int ip6_route_init(void); 97 void ip6_route_cleanup(void); 98 99 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg); 100 101 int ip6_route_add(struct fib6_config *cfg, struct netlink_ext_ack *extack); 102 int ip6_ins_rt(struct rt6_info *); 103 int ip6_del_rt(struct rt6_info *); 104 105 void rt6_flush_exceptions(struct rt6_info *rt); 106 int rt6_remove_exception_rt(struct rt6_info *rt); 107 void rt6_age_exceptions(struct rt6_info *rt, struct fib6_gc_args *gc_args, 108 unsigned long now); 109 110 static inline int ip6_route_get_saddr(struct net *net, struct rt6_info *rt, 111 const struct in6_addr *daddr, 112 unsigned int prefs, 113 struct in6_addr *saddr) 114 { 115 struct inet6_dev *idev = 116 rt ? ip6_dst_idev((struct dst_entry *)rt) : NULL; 117 int err = 0; 118 119 if (rt && rt->rt6i_prefsrc.plen) 120 *saddr = rt->rt6i_prefsrc.addr; 121 else 122 err = ipv6_dev_get_saddr(net, idev ? idev->dev : NULL, 123 daddr, prefs, saddr); 124 125 return err; 126 } 127 128 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr, 129 const struct in6_addr *saddr, int oif, int flags); 130 u32 rt6_multipath_hash(const struct flowi6 *fl6, const struct sk_buff *skb); 131 132 struct dst_entry *icmp6_dst_alloc(struct net_device *dev, struct flowi6 *fl6); 133 134 void fib6_force_start_gc(struct net *net); 135 136 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev, 137 const struct in6_addr *addr, bool anycast); 138 139 struct rt6_info *ip6_dst_alloc(struct net *net, struct net_device *dev, 140 int flags); 141 142 /* 143 * support functions for ND 144 * 145 */ 146 struct rt6_info *rt6_get_dflt_router(const struct in6_addr *addr, 147 struct net_device *dev); 148 struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr, 149 struct net_device *dev, unsigned int pref); 150 151 void rt6_purge_dflt_routers(struct net *net); 152 153 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len, 154 const struct in6_addr *gwaddr); 155 156 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu, int oif, 157 u32 mark, kuid_t uid); 158 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu); 159 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark, 160 kuid_t uid); 161 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif, 162 u32 mark); 163 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk); 164 165 struct netlink_callback; 166 167 struct rt6_rtnl_dump_arg { 168 struct sk_buff *skb; 169 struct netlink_callback *cb; 170 struct net *net; 171 }; 172 173 int rt6_dump_route(struct rt6_info *rt, void *p_arg); 174 void rt6_mtu_change(struct net_device *dev, unsigned int mtu); 175 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp); 176 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway); 177 void rt6_sync_up(struct net_device *dev, unsigned int nh_flags); 178 void rt6_disable_ip(struct net_device *dev, unsigned long event); 179 void rt6_sync_down_dev(struct net_device *dev, unsigned long event); 180 void rt6_multipath_rebalance(struct rt6_info *rt); 181 182 static inline const struct rt6_info *skb_rt6_info(const struct sk_buff *skb) 183 { 184 const struct dst_entry *dst = skb_dst(skb); 185 const struct rt6_info *rt6 = NULL; 186 187 if (dst) 188 rt6 = container_of(dst, struct rt6_info, dst); 189 190 return rt6; 191 } 192 193 /* 194 * Store a destination cache entry in a socket 195 */ 196 static inline void ip6_dst_store(struct sock *sk, struct dst_entry *dst, 197 const struct in6_addr *daddr, 198 const struct in6_addr *saddr) 199 { 200 struct ipv6_pinfo *np = inet6_sk(sk); 201 202 np->dst_cookie = rt6_get_cookie((struct rt6_info *)dst); 203 sk_setup_caps(sk, dst); 204 np->daddr_cache = daddr; 205 #ifdef CONFIG_IPV6_SUBTREES 206 np->saddr_cache = saddr; 207 #endif 208 } 209 210 static inline bool ipv6_unicast_destination(const struct sk_buff *skb) 211 { 212 struct rt6_info *rt = (struct rt6_info *) skb_dst(skb); 213 214 return rt->rt6i_flags & RTF_LOCAL; 215 } 216 217 static inline bool ipv6_anycast_destination(const struct dst_entry *dst, 218 const struct in6_addr *daddr) 219 { 220 struct rt6_info *rt = (struct rt6_info *)dst; 221 222 return rt->rt6i_flags & RTF_ANYCAST || 223 (rt->rt6i_dst.plen < 127 && 224 ipv6_addr_equal(&rt->rt6i_dst.addr, daddr)); 225 } 226 227 int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb, 228 int (*output)(struct net *, struct sock *, struct sk_buff *)); 229 230 static inline int ip6_skb_dst_mtu(struct sk_buff *skb) 231 { 232 struct ipv6_pinfo *np = skb->sk && !dev_recursion_level() ? 233 inet6_sk(skb->sk) : NULL; 234 235 return (np && np->pmtudisc >= IPV6_PMTUDISC_PROBE) ? 236 skb_dst(skb)->dev->mtu : dst_mtu(skb_dst(skb)); 237 } 238 239 static inline bool ip6_sk_accept_pmtu(const struct sock *sk) 240 { 241 return inet6_sk(sk)->pmtudisc != IPV6_PMTUDISC_INTERFACE && 242 inet6_sk(sk)->pmtudisc != IPV6_PMTUDISC_OMIT; 243 } 244 245 static inline bool ip6_sk_ignore_df(const struct sock *sk) 246 { 247 return inet6_sk(sk)->pmtudisc < IPV6_PMTUDISC_DO || 248 inet6_sk(sk)->pmtudisc == IPV6_PMTUDISC_OMIT; 249 } 250 251 static inline struct in6_addr *rt6_nexthop(struct rt6_info *rt, 252 struct in6_addr *daddr) 253 { 254 if (rt->rt6i_flags & RTF_GATEWAY) 255 return &rt->rt6i_gateway; 256 else if (unlikely(rt->rt6i_flags & RTF_CACHE)) 257 return &rt->rt6i_dst.addr; 258 else 259 return daddr; 260 } 261 262 static inline bool rt6_duplicate_nexthop(struct rt6_info *a, struct rt6_info *b) 263 { 264 return a->dst.dev == b->dst.dev && 265 a->rt6i_idev == b->rt6i_idev && 266 ipv6_addr_equal(&a->rt6i_gateway, &b->rt6i_gateway) && 267 !lwtunnel_cmp_encap(a->dst.lwtstate, b->dst.lwtstate); 268 } 269 #endif 270