1 /*- 2 * Copyright 1994, 1995 Massachusetts Institute of Technology 3 * 4 * Permission to use, copy, modify, and distribute this software and 5 * its documentation for any purpose and without fee is hereby 6 * granted, provided that both the above copyright notice and this 7 * permission notice appear in all copies, that both the above 8 * copyright notice and this permission notice appear in all 9 * supporting documentation, and that the name of M.I.T. not be used 10 * in advertising or publicity pertaining to distribution of the 11 * software without specific, written prior permission. M.I.T. makes 12 * no representations about the suitability of this software for any 13 * purpose. It is provided "as is" without express or implied 14 * warranty. 15 * 16 * THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''. M.I.T. DISCLAIMS 17 * ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE, 18 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT 20 * SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF 23 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 25 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 26 * 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 <sys/param.h> 34 #include <sys/systm.h> 35 #include <sys/kernel.h> 36 #include <sys/sysctl.h> 37 #include <sys/socket.h> 38 #include <sys/mbuf.h> 39 40 #include <net/if.h> 41 #include <net/if_var.h> 42 #include <net/route.h> 43 #include <net/vnet.h> 44 45 #include <netinet/in.h> 46 #include <netinet/in_var.h> 47 #include <netinet/ip.h> 48 #include <netinet/ip_icmp.h> 49 #include <netinet/ip_var.h> 50 51 extern int in_inithead(void **head, int off); 52 #ifdef VIMAGE 53 extern int in_detachhead(void **head, int off); 54 #endif 55 56 /* 57 * Do what we need to do when inserting a route. 58 */ 59 static struct radix_node * 60 in_addroute(void *v_arg, void *n_arg, struct radix_node_head *head, 61 struct radix_node *treenodes) 62 { 63 struct rtentry *rt = (struct rtentry *)treenodes; 64 struct sockaddr_in *sin = (struct sockaddr_in *)rt_key(rt); 65 66 RADIX_NODE_HEAD_WLOCK_ASSERT(head); 67 /* 68 * A little bit of help for both IP output and input: 69 * For host routes, we make sure that RTF_BROADCAST 70 * is set for anything that looks like a broadcast address. 71 * This way, we can avoid an expensive call to in_broadcast() 72 * in ip_output() most of the time (because the route passed 73 * to ip_output() is almost always a host route). 74 * 75 * We also do the same for local addresses, with the thought 76 * that this might one day be used to speed up ip_input(). 77 * 78 * We also mark routes to multicast addresses as such, because 79 * it's easy to do and might be useful (but this is much more 80 * dubious since it's so easy to inspect the address). 81 */ 82 if (rt->rt_flags & RTF_HOST) { 83 if (in_broadcast(sin->sin_addr, rt->rt_ifp)) { 84 rt->rt_flags |= RTF_BROADCAST; 85 } else if (satosin(rt->rt_ifa->ifa_addr)->sin_addr.s_addr == 86 sin->sin_addr.s_addr) { 87 rt->rt_flags |= RTF_LOCAL; 88 } 89 } 90 if (IN_MULTICAST(ntohl(sin->sin_addr.s_addr))) 91 rt->rt_flags |= RTF_MULTICAST; 92 93 if (rt->rt_ifp != NULL) { 94 95 /* 96 * Check route MTU: 97 * inherit interface MTU if not set or 98 * check if MTU is too large. 99 */ 100 if (rt->rt_mtu == 0) { 101 rt->rt_mtu = rt->rt_ifp->if_mtu; 102 } else if (rt->rt_mtu > rt->rt_ifp->if_mtu) 103 rt->rt_mtu = rt->rt_ifp->if_mtu; 104 } 105 106 return (rn_addroute(v_arg, n_arg, head, treenodes)); 107 } 108 109 static int _in_rt_was_here; 110 /* 111 * Initialize our routing tree. 112 */ 113 int 114 in_inithead(void **head, int off) 115 { 116 struct radix_node_head *rnh; 117 118 if (!rn_inithead(head, 32)) 119 return 0; 120 121 rnh = *head; 122 RADIX_NODE_HEAD_LOCK_INIT(rnh); 123 124 rnh->rnh_addaddr = in_addroute; 125 if (_in_rt_was_here == 0 ) { 126 _in_rt_was_here = 1; 127 } 128 return 1; 129 } 130 131 #ifdef VIMAGE 132 int 133 in_detachhead(void **head, int off) 134 { 135 136 return (1); 137 } 138 #endif 139 140 /* 141 * This zaps old routes when the interface goes down or interface 142 * address is deleted. In the latter case, it deletes static routes 143 * that point to this address. If we don't do this, we may end up 144 * using the old address in the future. The ones we always want to 145 * get rid of are things like ARP entries, since the user might down 146 * the interface, walk over to a completely different network, and 147 * plug back in. 148 */ 149 struct in_ifadown_arg { 150 struct radix_node_head *rnh; 151 struct ifaddr *ifa; 152 int del; 153 }; 154 155 static int 156 in_ifadownkill(struct radix_node *rn, void *xap) 157 { 158 struct in_ifadown_arg *ap = xap; 159 struct rtentry *rt = (struct rtentry *)rn; 160 161 RT_LOCK(rt); 162 if (rt->rt_ifa == ap->ifa && 163 (ap->del || !(rt->rt_flags & RTF_STATIC))) { 164 /* 165 * Aquire a reference so that it can later be freed 166 * as the refcount would be 0 here in case of at least 167 * ap->del. 168 */ 169 RT_ADDREF(rt); 170 /* 171 * Disconnect it from the tree and permit protocols 172 * to cleanup. 173 */ 174 rt_expunge(ap->rnh, rt); 175 /* 176 * At this point it is an rttrash node, and in case 177 * the above is the only reference we must free it. 178 * If we do not noone will have a pointer and the 179 * rtentry will be leaked forever. 180 * In case someone else holds a reference, we are 181 * fine as we only decrement the refcount. In that 182 * case if the other entity calls RT_REMREF, we 183 * will still be leaking but at least we tried. 184 */ 185 RTFREE_LOCKED(rt); 186 return (0); 187 } 188 RT_UNLOCK(rt); 189 return 0; 190 } 191 192 void 193 in_ifadown(struct ifaddr *ifa, int delete) 194 { 195 struct in_ifadown_arg arg; 196 struct radix_node_head *rnh; 197 int fibnum; 198 199 KASSERT(ifa->ifa_addr->sa_family == AF_INET, 200 ("%s: wrong family", __func__)); 201 202 for ( fibnum = 0; fibnum < rt_numfibs; fibnum++) { 203 rnh = rt_tables_get_rnh(fibnum, AF_INET); 204 arg.rnh = rnh; 205 arg.ifa = ifa; 206 arg.del = delete; 207 RADIX_NODE_HEAD_LOCK(rnh); 208 rnh->rnh_walktree(rnh, in_ifadownkill, &arg); 209 RADIX_NODE_HEAD_UNLOCK(rnh); 210 ifa->ifa_flags &= ~IFA_ROUTE; /* XXXlocking? */ 211 } 212 } 213 214 /* 215 * inet versions of rt functions. These have fib extensions and 216 * for now will just reference the _fib variants. 217 * eventually this order will be reversed, 218 */ 219 void 220 in_rtalloc_ign(struct route *ro, u_long ignflags, u_int fibnum) 221 { 222 rtalloc_ign_fib(ro, ignflags, fibnum); 223 } 224 225 int 226 in_rtrequest( int req, 227 struct sockaddr *dst, 228 struct sockaddr *gateway, 229 struct sockaddr *netmask, 230 int flags, 231 struct rtentry **ret_nrt, 232 u_int fibnum) 233 { 234 return (rtrequest_fib(req, dst, gateway, netmask, 235 flags, ret_nrt, fibnum)); 236 } 237 238 struct rtentry * 239 in_rtalloc1(struct sockaddr *dst, int report, u_long ignflags, u_int fibnum) 240 { 241 return (rtalloc1_fib(dst, report, ignflags, fibnum)); 242 } 243 244 void 245 in_rtredirect(struct sockaddr *dst, 246 struct sockaddr *gateway, 247 struct sockaddr *netmask, 248 int flags, 249 struct sockaddr *src, 250 u_int fibnum) 251 { 252 rtredirect_fib(dst, gateway, netmask, flags, src, fibnum); 253 } 254 255 void 256 in_rtalloc(struct route *ro, u_int fibnum) 257 { 258 rtalloc_ign_fib(ro, 0UL, fibnum); 259 } 260 261 #if 0 262 int in_rt_getifa(struct rt_addrinfo *, u_int fibnum); 263 int in_rtioctl(u_long, caddr_t, u_int); 264 int in_rtrequest1(int, struct rt_addrinfo *, struct rtentry **, u_int); 265 #endif 266 267 268