1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2020 Alexander V. Chernikov 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 /* 29 * This header file contains public definitions for the nexthop routing subsystem. 30 */ 31 32 #ifndef _NET_ROUTE_NHOP_H_ 33 #define _NET_ROUTE_NHOP_H_ 34 35 #include <netinet/in.h> /* sockaddr_in && sockaddr_in6 */ 36 37 #include <sys/counter.h> 38 39 enum nhop_type { 40 NH_TYPE_IPV4_ETHER_RSLV = 1, /* IPv4 ethernet without GW */ 41 NH_TYPE_IPV4_ETHER_NHOP = 2, /* IPv4 with pre-calculated ethernet encap */ 42 NH_TYPE_IPV6_ETHER_RSLV = 3, /* IPv6 ethernet, without GW */ 43 NH_TYPE_IPV6_ETHER_NHOP = 4 /* IPv6 with pre-calculated ethernet encap*/ 44 }; 45 46 #ifdef _KERNEL 47 48 /* 49 * Define shorter version of AF_LINK sockaddr. 50 * 51 * Currently the only use case of AF_LINK gateway is storing 52 * interface index of the interface of the source IPv6 address. 53 * This is used by the IPv6 code for the connections over loopback 54 * interface. 55 * 56 * The structure below copies 'struct sockaddr_dl', reducing the 57 * size of sdl_data buffer, as it is not used. This change 58 * allows to store the AF_LINK gateways in the nhop gateway itself, 59 * simplifying control plane handling. 60 */ 61 struct sockaddr_dl_short { 62 u_char sdl_len; /* Total length of sockaddr */ 63 u_char sdl_family; /* AF_LINK */ 64 u_short sdl_index; /* if != 0, system given index for interface */ 65 u_char sdl_type; /* interface type */ 66 u_char sdl_nlen; /* interface name length, no trailing 0 reqd. */ 67 u_char sdl_alen; /* link level address length */ 68 u_char sdl_slen; /* link layer selector length */ 69 char sdl_data[8]; /* unused */ 70 }; 71 72 #define NHOP_RELATED_FLAGS \ 73 (RTF_GATEWAY | RTF_HOST | RTF_REJECT | RTF_BLACKHOLE | \ 74 RTF_FIXEDMTU | RTF_LOCAL | RTF_BROADCAST | RTF_MULTICAST) 75 76 struct nh_control; 77 struct nhop_priv; 78 79 /* 80 * Struct 'nhop_object' field description: 81 * 82 * nh_flags: NHF_ flags used in the dataplane code. NHF_GATEWAY or NHF_BLACKHOLE 83 * can be examples of such flags. 84 * nh_mtu: ready-to-use nexthop mtu. Already accounts for the link-level header, 85 * interface MTU and protocol-specific limitations. 86 * nh_prepend_len: link-level prepend length. Currently unused. 87 * nh_ifp: logical transmit interface. The one from which if_transmit() will be 88 * called. Guaranteed to be non-NULL. 89 * nh_aifp: ifnet of the source address. Same as nh_ifp except IPv6 loopback 90 * routes. See the example below. 91 * nh_ifa: interface address to use. Guaranteed to be non-NULL. 92 * nh_pksent: counter(9) reflecting the number of packets transmitted. 93 * 94 * gw_: storage suitable to hold AF_INET, AF_INET6 or AF_LINK gateway. More 95 * details ara available in the examples below. 96 * 97 * Examples: 98 * 99 * Direct routes (routes w/o gateway): 100 * NHF_GATEWAY is NOT set. 101 * nh_ifp denotes the logical transmit interface (). 102 * nh_aifp is the same as nh_ifp 103 * gw_sa contains AF_LINK sa with nh_aifp ifindex (compat) 104 * Loopback routes: 105 * NHF_GATEWAY is NOT set. 106 * nh_ifp points to the loopback interface (lo0). 107 * nh_aifp points to the interface where the destination address belongs to. 108 * This is useful in IPv6 link-local-over-loopback communications. 109 * gw_sa contains AF_LINK sa with nh_aifp ifindex (compat) 110 * GW routes: 111 * NHF_GATEWAY is set. 112 * nh_ifp denotes the logical transmit interface. 113 * nh_aifp is the same as nh_ifp 114 * gw_sa contains L3 address (either AF_INET or AF_INET6). 115 * 116 * 117 * Note: struct nhop_object fields are ordered in a way that 118 * supports memcmp-based comparisons. 119 * 120 */ 121 #define NHOP_END_CMP (__offsetof(struct nhop_object, nh_pksent)) 122 123 struct nhop_object { 124 uint16_t nh_flags; /* nhop flags */ 125 uint16_t nh_mtu; /* nexthop mtu */ 126 union { 127 struct sockaddr_in gw4_sa; /* GW accessor as IPv4 */ 128 struct sockaddr_in6 gw6_sa; /* GW accessor as IPv6 */ 129 struct sockaddr gw_sa; 130 struct sockaddr_dl_short gwl_sa; /* AF_LINK gw (compat) */ 131 char gw_buf[28]; 132 }; 133 struct ifnet *nh_ifp; /* Logical egress interface. Always != NULL */ 134 struct ifaddr *nh_ifa; /* interface address to use. Always != NULL */ 135 struct ifnet *nh_aifp; /* ifnet of the source address. Always != NULL */ 136 counter_u64_t nh_pksent; /* packets sent using this nhop */ 137 /* 32 bytes + 4xPTR == 64(amd64) / 48(i386) */ 138 uint8_t nh_prepend_len; /* length of prepend data */ 139 uint8_t spare[3]; 140 uint32_t spare1; /* alignment */ 141 char nh_prepend[48]; /* L2 prepend */ 142 struct nhop_priv *nh_priv; /* control plane data */ 143 /* -- 128 bytes -- */ 144 }; 145 146 /* 147 * Nhop validness. 148 * 149 * Currently we verify whether link is up or not on every packet, which can be 150 * quite costy. 151 * TODO: subscribe for the interface notifications and update the nexthops 152 * with NHF_INVALID flag. 153 */ 154 155 #define NH_IS_VALID(_nh) RT_LINK_IS_UP((_nh)->nh_ifp) 156 #define NH_IS_NHGRP(_nh) ((_nh)->nh_flags & NHF_MULTIPATH) 157 158 #define NH_FREE(_nh) do { \ 159 nhop_free(_nh); \ 160 /* guard against invalid refs */ \ 161 _nh = NULL; \ 162 } while (0) 163 164 struct weightened_nhop { 165 struct nhop_object *nh; 166 uint32_t weight; 167 uint32_t storage; 168 }; 169 170 void nhop_free(struct nhop_object *nh); 171 172 struct sysctl_req; 173 struct sockaddr_dl; 174 struct rib_head; 175 176 /* flags that can be set using nhop_set_rtflags() */ 177 #define RT_SET_RTFLAGS_MASK (RTF_PROTO1 | RTF_PROTO2 | RTF_PROTO3 | RTF_STATIC) 178 #define RT_CHANGE_RTFLAGS_MASK RT_SET_RTFLAGS_MASK 179 180 struct nhop_object *nhop_alloc(uint32_t fibnum, int family); 181 void nhop_copy(struct nhop_object *nh, const struct nhop_object *nh_orig); 182 struct nhop_object *nhop_get_nhop(struct nhop_object *nh, int *perror); 183 int nhop_get_unlinked(struct nhop_object *nh); 184 185 void nhop_set_direct_gw(struct nhop_object *nh, struct ifnet *ifp); 186 bool nhop_set_gw(struct nhop_object *nh, const struct sockaddr *sa, bool is_gw); 187 188 189 void nhop_set_mtu(struct nhop_object *nh, uint32_t mtu, bool from_user); 190 void nhop_set_rtflags(struct nhop_object *nh, int rt_flags); 191 void nhop_set_pxtype_flag(struct nhop_object *nh, int nh_flag); 192 void nhop_set_broadcast(struct nhop_object *nh, bool is_broadcast); 193 void nhop_set_blackhole(struct nhop_object *nh, int blackhole_rt_flag); 194 void nhop_set_pinned(struct nhop_object *nh, bool is_pinned); 195 void nhop_set_redirect(struct nhop_object *nh, bool is_redirect); 196 void nhop_set_type(struct nhop_object *nh, enum nhop_type nh_type); 197 void nhop_set_src(struct nhop_object *nh, struct ifaddr *ifa); 198 void nhop_set_transmit_ifp(struct nhop_object *nh, struct ifnet *ifp); 199 200 #define NH_ORIGIN_UNSPEC 0 /* not set */ 201 #define NH_ORIGIN_REDIRECT 1 /* kernel-originated redirect */ 202 #define NH_ORIGIN_KERNEL 2 /* kernel (interface) routes */ 203 #define NH_ORIGIN_BOOT 3 /* kernel-originated routes at boot */ 204 #define NH_ORIGIN_STATIC 4 /* route(8) routes */ 205 void nhop_set_origin(struct nhop_object *nh, uint8_t origin); 206 uint8_t nhop_get_origin(const struct nhop_object *nh); 207 208 uint32_t nhop_get_idx(const struct nhop_object *nh); 209 uint32_t nhop_get_uidx(const struct nhop_object *nh); 210 void nhop_set_uidx(struct nhop_object *nh, uint32_t uidx); 211 enum nhop_type nhop_get_type(const struct nhop_object *nh); 212 int nhop_get_rtflags(const struct nhop_object *nh); 213 struct vnet *nhop_get_vnet(const struct nhop_object *nh); 214 struct nhop_object *nhop_select_func(struct nhop_object *nh, uint32_t flowid); 215 int nhop_get_upper_family(const struct nhop_object *nh); 216 bool nhop_set_upper_family(struct nhop_object *nh, int family); 217 int nhop_get_neigh_family(const struct nhop_object *nh); 218 uint32_t nhop_get_fibnum(const struct nhop_object *nh); 219 void nhop_set_fibnum(struct nhop_object *nh, uint32_t fibnum); 220 uint32_t nhop_get_expire(const struct nhop_object *nh); 221 void nhop_set_expire(struct nhop_object *nh, uint32_t expire); 222 struct rib_head *nhop_get_rh(const struct nhop_object *nh); 223 224 struct nhgrp_object; 225 struct nhgrp_object *nhgrp_alloc(uint32_t fibnum, int family, 226 struct weightened_nhop *wn, int num_nhops, int *perror); 227 struct nhgrp_object *nhgrp_get_nhgrp(struct nhgrp_object *nhg, int *perror); 228 void nhgrp_set_uidx(struct nhgrp_object *nhg, uint32_t uidx); 229 uint32_t nhgrp_get_uidx(const struct nhgrp_object *nhg); 230 uint8_t nhgrp_get_origin(const struct nhgrp_object *nhg); 231 void nhgrp_set_origin(struct nhgrp_object *nhg, uint8_t origin); 232 #endif /* _KERNEL */ 233 234 /* Kernel <> userland structures */ 235 236 /* Structure usage and layout are described in dump_nhop_entry() */ 237 struct nhop_external { 238 uint32_t nh_len; /* length of the datastructure */ 239 uint32_t nh_idx; /* Nexthop index */ 240 uint32_t nh_fib; /* Fib nexhop is attached to */ 241 uint32_t ifindex; /* transmit interface ifindex */ 242 uint32_t aifindex; /* address ifindex */ 243 uint8_t prepend_len; /* length of the prepend */ 244 uint8_t nh_family; /* address family */ 245 uint16_t nh_type; /* nexthop type */ 246 uint16_t nh_mtu; /* nexthop mtu */ 247 248 uint16_t nh_flags; /* nhop flags */ 249 struct in_addr nh_addr; /* GW/DST IPv4 address */ 250 struct in_addr nh_src; /* default source IPv4 address */ 251 uint64_t nh_pksent; 252 /* control plane */ 253 /* lookup key: address, family, type */ 254 char nh_prepend[64]; /* L2 prepend */ 255 uint64_t nh_refcount; /* number of references */ 256 }; 257 258 struct nhop_addrs { 259 uint32_t na_len; /* length of the datastructure */ 260 uint16_t gw_sa_off; /* offset of gateway SA */ 261 uint16_t src_sa_off; /* offset of src address SA */ 262 }; 263 264 #define NHG_C_TYPE_CNHOPS 0x1 /* Control plane nhops list */ 265 #define NHG_C_TYPE_DNHOPS 0x2 /* Dataplane nhops list */ 266 struct nhgrp_container { 267 uint32_t nhgc_len; /* container length */ 268 uint16_t nhgc_count; /* number of items */ 269 uint8_t nhgc_type; /* container type */ 270 uint8_t nhgc_subtype; /* container subtype */ 271 }; 272 273 struct nhgrp_nhop_external { 274 uint32_t nh_idx; 275 uint32_t nh_weight; 276 }; 277 278 /* 279 * Layout: 280 * - nhgrp_external 281 * - nhgrp_container (control plane nhops list) 282 * - nhgrp_nhop_external 283 * - nhgrp_nhop_external 284 * .. 285 * - nhgrp_container (dataplane nhops list) 286 * - nhgrp_nhop_external 287 * - nhgrp_nhop_external 288 */ 289 struct nhgrp_external { 290 uint32_t nhg_idx; /* Nexthop group index */ 291 uint32_t nhg_refcount; /* number of references */ 292 }; 293 294 #endif 295