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