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 void ip6_route_input(struct sk_buff *skb); 70 struct dst_entry *ip6_route_input_lookup(struct net *net, 71 struct net_device *dev, 72 struct flowi6 *fl6, int flags); 73 74 struct dst_entry *ip6_route_output_flags(struct net *net, const struct sock *sk, 75 struct flowi6 *fl6, int flags); 76 77 static inline struct dst_entry *ip6_route_output(struct net *net, 78 const struct sock *sk, 79 struct flowi6 *fl6) 80 { 81 return ip6_route_output_flags(net, sk, fl6, 0); 82 } 83 84 struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6, 85 int flags); 86 struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table, 87 int ifindex, struct flowi6 *fl6, int flags); 88 89 void ip6_route_init_special_entries(void); 90 int ip6_route_init(void); 91 void ip6_route_cleanup(void); 92 93 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg); 94 95 int ip6_route_add(struct fib6_config *cfg, struct netlink_ext_ack *extack); 96 int ip6_ins_rt(struct rt6_info *); 97 int ip6_del_rt(struct rt6_info *); 98 99 void rt6_flush_exceptions(struct rt6_info *rt); 100 int rt6_remove_exception_rt(struct rt6_info *rt); 101 void rt6_age_exceptions(struct rt6_info *rt, struct fib6_gc_args *gc_args, 102 unsigned long now); 103 104 static inline int ip6_route_get_saddr(struct net *net, struct rt6_info *rt, 105 const struct in6_addr *daddr, 106 unsigned int prefs, 107 struct in6_addr *saddr) 108 { 109 struct inet6_dev *idev = 110 rt ? ip6_dst_idev((struct dst_entry *)rt) : NULL; 111 int err = 0; 112 113 if (rt && rt->rt6i_prefsrc.plen) 114 *saddr = rt->rt6i_prefsrc.addr; 115 else 116 err = ipv6_dev_get_saddr(net, idev ? idev->dev : NULL, 117 daddr, prefs, saddr); 118 119 return err; 120 } 121 122 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr, 123 const struct in6_addr *saddr, int oif, int flags); 124 u32 rt6_multipath_hash(const struct flowi6 *fl6, const struct sk_buff *skb); 125 126 struct dst_entry *icmp6_dst_alloc(struct net_device *dev, struct flowi6 *fl6); 127 128 void fib6_force_start_gc(struct net *net); 129 130 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev, 131 const struct in6_addr *addr, bool anycast); 132 133 struct rt6_info *ip6_dst_alloc(struct net *net, struct net_device *dev, 134 int flags); 135 136 /* 137 * support functions for ND 138 * 139 */ 140 struct rt6_info *rt6_get_dflt_router(const struct in6_addr *addr, 141 struct net_device *dev); 142 struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr, 143 struct net_device *dev, unsigned int pref); 144 145 void rt6_purge_dflt_routers(struct net *net); 146 147 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len, 148 const struct in6_addr *gwaddr); 149 150 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu, int oif, 151 u32 mark, kuid_t uid); 152 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu); 153 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark, 154 kuid_t uid); 155 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif, 156 u32 mark); 157 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk); 158 159 struct netlink_callback; 160 161 struct rt6_rtnl_dump_arg { 162 struct sk_buff *skb; 163 struct netlink_callback *cb; 164 struct net *net; 165 }; 166 167 int rt6_dump_route(struct rt6_info *rt, void *p_arg); 168 void rt6_ifdown(struct net *net, struct net_device *dev); 169 void rt6_mtu_change(struct net_device *dev, unsigned int mtu); 170 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp); 171 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway); 172 173 static inline const struct rt6_info *skb_rt6_info(const struct sk_buff *skb) 174 { 175 const struct dst_entry *dst = skb_dst(skb); 176 const struct rt6_info *rt6 = NULL; 177 178 if (dst) 179 rt6 = container_of(dst, struct rt6_info, dst); 180 181 return rt6; 182 } 183 184 /* 185 * Store a destination cache entry in a socket 186 */ 187 static inline void ip6_dst_store(struct sock *sk, struct dst_entry *dst, 188 const struct in6_addr *daddr, 189 const struct in6_addr *saddr) 190 { 191 struct ipv6_pinfo *np = inet6_sk(sk); 192 193 np->dst_cookie = rt6_get_cookie((struct rt6_info *)dst); 194 sk_setup_caps(sk, dst); 195 np->daddr_cache = daddr; 196 #ifdef CONFIG_IPV6_SUBTREES 197 np->saddr_cache = saddr; 198 #endif 199 } 200 201 static inline bool ipv6_unicast_destination(const struct sk_buff *skb) 202 { 203 struct rt6_info *rt = (struct rt6_info *) skb_dst(skb); 204 205 return rt->rt6i_flags & RTF_LOCAL; 206 } 207 208 static inline bool ipv6_anycast_destination(const struct dst_entry *dst, 209 const struct in6_addr *daddr) 210 { 211 struct rt6_info *rt = (struct rt6_info *)dst; 212 213 return rt->rt6i_flags & RTF_ANYCAST || 214 (rt->rt6i_dst.plen < 127 && 215 ipv6_addr_equal(&rt->rt6i_dst.addr, daddr)); 216 } 217 218 int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb, 219 int (*output)(struct net *, struct sock *, struct sk_buff *)); 220 221 static inline int ip6_skb_dst_mtu(struct sk_buff *skb) 222 { 223 struct ipv6_pinfo *np = skb->sk && !dev_recursion_level() ? 224 inet6_sk(skb->sk) : NULL; 225 226 return (np && np->pmtudisc >= IPV6_PMTUDISC_PROBE) ? 227 skb_dst(skb)->dev->mtu : dst_mtu(skb_dst(skb)); 228 } 229 230 static inline bool ip6_sk_accept_pmtu(const struct sock *sk) 231 { 232 return inet6_sk(sk)->pmtudisc != IPV6_PMTUDISC_INTERFACE && 233 inet6_sk(sk)->pmtudisc != IPV6_PMTUDISC_OMIT; 234 } 235 236 static inline bool ip6_sk_ignore_df(const struct sock *sk) 237 { 238 return inet6_sk(sk)->pmtudisc < IPV6_PMTUDISC_DO || 239 inet6_sk(sk)->pmtudisc == IPV6_PMTUDISC_OMIT; 240 } 241 242 static inline struct in6_addr *rt6_nexthop(struct rt6_info *rt, 243 struct in6_addr *daddr) 244 { 245 if (rt->rt6i_flags & RTF_GATEWAY) 246 return &rt->rt6i_gateway; 247 else if (unlikely(rt->rt6i_flags & RTF_CACHE)) 248 return &rt->rt6i_dst.addr; 249 else 250 return daddr; 251 } 252 253 static inline bool rt6_duplicate_nexthop(struct rt6_info *a, struct rt6_info *b) 254 { 255 return a->dst.dev == b->dst.dev && 256 a->rt6i_idev == b->rt6i_idev && 257 ipv6_addr_equal(&a->rt6i_gateway, &b->rt6i_gateway) && 258 !lwtunnel_cmp_encap(a->dst.lwtstate, b->dst.lwtstate); 259 } 260 #endif 261