1 /*- 2 * Copyright (c) 2015 3 * Alexander V. Chernikov <melifaro@FreeBSD.org> 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30 #include <sys/cdefs.h> 31 __FBSDID("$FreeBSD$"); 32 33 #include "opt_inet.h" 34 #include "opt_route.h" 35 36 #include <sys/param.h> 37 #include <sys/systm.h> 38 #include <sys/lock.h> 39 #include <sys/rmlock.h> 40 #include <sys/malloc.h> 41 #include <sys/mbuf.h> 42 #include <sys/socket.h> 43 #include <sys/sysctl.h> 44 #include <sys/kernel.h> 45 46 #include <net/if.h> 47 #include <net/if_var.h> 48 #include <net/if_dl.h> 49 #include <net/route.h> 50 #include <net/route/route_ctl.h> 51 #include <net/route/route_var.h> 52 #include <net/route/nhop.h> 53 #include <net/toeplitz.h> 54 #include <net/vnet.h> 55 56 #include <netinet/in.h> 57 #include <netinet/in_var.h> 58 #include <netinet/in_fib.h> 59 60 #ifdef INET 61 62 /* Verify struct route compatiblity */ 63 /* Assert 'struct route_in' is compatible with 'struct route' */ 64 CHK_STRUCT_ROUTE_COMPAT(struct route_in, ro_dst4); 65 66 #ifdef ROUTE_MPATH 67 struct _hash_5tuple_ipv4 { 68 struct in_addr src; 69 struct in_addr dst; 70 unsigned short src_port; 71 unsigned short dst_port; 72 char proto; 73 char spare[3]; 74 }; 75 _Static_assert(sizeof(struct _hash_5tuple_ipv4) == 16, 76 "_hash_5tuple_ipv4 size is wrong"); 77 78 79 uint32_t 80 fib4_calc_software_hash(struct in_addr src, struct in_addr dst, 81 unsigned short src_port, unsigned short dst_port, char proto, 82 uint32_t *phashtype) 83 { 84 struct _hash_5tuple_ipv4 data; 85 86 data.src = src; 87 data.dst = dst; 88 data.src_port = src_port; 89 data.dst_port = dst_port; 90 data.proto = proto; 91 data.spare[0] = data.spare[1] = data.spare[2] = 0; 92 93 *phashtype = M_HASHTYPE_OPAQUE; 94 95 return (toeplitz_hash(MPATH_ENTROPY_KEY_LEN, mpath_entropy_key, 96 sizeof(data), (uint8_t *)&data)); 97 } 98 #endif 99 100 /* 101 * Looks up path in fib @fibnum specified by @dst. 102 * Returns path nexthop on success. Nexthop is safe to use 103 * within the current network epoch. If longer lifetime is required, 104 * one needs to pass NHR_REF as a flag. This will return referenced 105 * nexthop. 106 */ 107 struct nhop_object * 108 fib4_lookup(uint32_t fibnum, struct in_addr dst, uint32_t scopeid, 109 uint32_t flags, uint32_t flowid) 110 { 111 RIB_RLOCK_TRACKER; 112 struct rib_head *rh; 113 struct radix_node *rn; 114 struct nhop_object *nh; 115 116 KASSERT((fibnum < rt_numfibs), ("fib4_lookup: bad fibnum")); 117 rh = rt_tables_get_rnh(fibnum, AF_INET); 118 if (rh == NULL) 119 return (NULL); 120 121 /* Prepare lookup key */ 122 struct sockaddr_in sin4; 123 memset(&sin4, 0, sizeof(sin4)); 124 sin4.sin_family = AF_INET; 125 sin4.sin_len = sizeof(struct sockaddr_in); 126 sin4.sin_addr = dst; 127 128 nh = NULL; 129 RIB_RLOCK(rh); 130 rn = rh->rnh_matchaddr((void *)&sin4, &rh->head); 131 if (rn != NULL && ((rn->rn_flags & RNF_ROOT) == 0)) { 132 nh = nhop_select((RNTORT(rn))->rt_nhop, flowid); 133 /* Ensure route & ifp is UP */ 134 if (RT_LINK_IS_UP(nh->nh_ifp)) { 135 if (flags & NHR_REF) 136 nhop_ref_object(nh); 137 RIB_RUNLOCK(rh); 138 return (nh); 139 } 140 } 141 RIB_RUNLOCK(rh); 142 143 RTSTAT_INC(rts_unreach); 144 return (NULL); 145 } 146 147 inline static int 148 check_urpf_nhop(const struct nhop_object *nh, uint32_t flags, 149 const struct ifnet *src_if) 150 { 151 152 if (src_if != NULL && nh->nh_aifp == src_if) { 153 return (1); 154 } 155 if (src_if == NULL) { 156 if ((flags & NHR_NODEFAULT) == 0) 157 return (1); 158 else if ((nh->nh_flags & NHF_DEFAULT) == 0) 159 return (1); 160 } 161 162 return (0); 163 } 164 165 static int 166 check_urpf(struct nhop_object *nh, uint32_t flags, 167 const struct ifnet *src_if) 168 { 169 #ifdef ROUTE_MPATH 170 if (NH_IS_NHGRP(nh)) { 171 struct weightened_nhop *wn; 172 uint32_t num_nhops; 173 wn = nhgrp_get_nhops((struct nhgrp_object *)nh, &num_nhops); 174 for (int i = 0; i < num_nhops; i++) { 175 if (check_urpf_nhop(wn[i].nh, flags, src_if) != 0) 176 return (1); 177 } 178 return (0); 179 } else 180 #endif 181 return (check_urpf_nhop(nh, flags, src_if)); 182 } 183 184 /* 185 * Performs reverse path forwarding lookup. 186 * If @src_if is non-zero, verifies that at least 1 path goes via 187 * this interface. 188 * If @src_if is zero, verifies that route exist. 189 * if @flags contains NHR_NOTDEFAULT, do not consider default route. 190 * 191 * Returns 1 if route matching conditions is found, 0 otherwise. 192 */ 193 int 194 fib4_check_urpf(uint32_t fibnum, struct in_addr dst, uint32_t scopeid, 195 uint32_t flags, const struct ifnet *src_if) 196 { 197 RIB_RLOCK_TRACKER; 198 struct rib_head *rh; 199 struct radix_node *rn; 200 int ret; 201 202 KASSERT((fibnum < rt_numfibs), ("fib4_check_urpf: bad fibnum")); 203 rh = rt_tables_get_rnh(fibnum, AF_INET); 204 if (rh == NULL) 205 return (0); 206 207 /* Prepare lookup key */ 208 struct sockaddr_in sin4; 209 memset(&sin4, 0, sizeof(sin4)); 210 sin4.sin_len = sizeof(struct sockaddr_in); 211 sin4.sin_addr = dst; 212 213 RIB_RLOCK(rh); 214 rn = rh->rnh_matchaddr((void *)&sin4, &rh->head); 215 if (rn != NULL && ((rn->rn_flags & RNF_ROOT) == 0)) { 216 ret = check_urpf(RNTORT(rn)->rt_nhop, flags, src_if); 217 RIB_RUNLOCK(rh); 218 return (ret); 219 } 220 RIB_RUNLOCK(rh); 221 222 return (0); 223 } 224 225 struct nhop_object * 226 fib4_lookup_debugnet(uint32_t fibnum, struct in_addr dst, uint32_t scopeid, 227 uint32_t flags) 228 { 229 struct rib_head *rh; 230 struct radix_node *rn; 231 struct nhop_object *nh; 232 233 KASSERT((fibnum < rt_numfibs), ("fib4_lookup_debugnet: bad fibnum")); 234 rh = rt_tables_get_rnh(fibnum, AF_INET); 235 if (rh == NULL) 236 return (NULL); 237 238 /* Prepare lookup key */ 239 struct sockaddr_in sin4; 240 memset(&sin4, 0, sizeof(sin4)); 241 sin4.sin_family = AF_INET; 242 sin4.sin_len = sizeof(struct sockaddr_in); 243 sin4.sin_addr = dst; 244 245 nh = NULL; 246 /* unlocked lookup */ 247 rn = rh->rnh_matchaddr((void *)&sin4, &rh->head); 248 if (rn != NULL && ((rn->rn_flags & RNF_ROOT) == 0)) { 249 nh = nhop_select((RNTORT(rn))->rt_nhop, 0); 250 /* Ensure route & ifp is UP */ 251 if (RT_LINK_IS_UP(nh->nh_ifp)) { 252 if (flags & NHR_REF) 253 nhop_ref_object(nh); 254 return (nh); 255 } 256 } 257 258 return (NULL); 259 } 260 261 #endif 262