mpls_ttl.c revision 1.2.2.3
1 1.2.2.2 rmind /* $NetBSD: mpls_ttl.c,v 1.2.2.3 2011/03/05 20:56:02 rmind Exp $ */ 2 1.2.2.2 rmind 3 1.2.2.2 rmind /* 4 1.2.2.2 rmind * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 5 1.2.2.2 rmind * All rights reserved. 6 1.2.2.2 rmind * 7 1.2.2.2 rmind * Redistribution and use in source and binary forms, with or without 8 1.2.2.2 rmind * modification, are permitted provided that the following conditions 9 1.2.2.2 rmind * are met: 10 1.2.2.2 rmind * 1. Redistributions of source code must retain the above copyright 11 1.2.2.2 rmind * notice, this list of conditions and the following disclaimer. 12 1.2.2.2 rmind * 2. Redistributions in binary form must reproduce the above copyright 13 1.2.2.2 rmind * notice, this list of conditions and the following disclaimer in the 14 1.2.2.2 rmind * documentation and/or other materials provided with the distribution. 15 1.2.2.2 rmind * 3. Neither the name of the project nor the names of its contributors 16 1.2.2.2 rmind * may be used to endorse or promote products derived from this software 17 1.2.2.2 rmind * without specific prior written permission. 18 1.2.2.2 rmind * 19 1.2.2.2 rmind * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 20 1.2.2.2 rmind * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 1.2.2.2 rmind * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 1.2.2.2 rmind * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 23 1.2.2.2 rmind * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 1.2.2.2 rmind * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 1.2.2.2 rmind * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 1.2.2.2 rmind * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 1.2.2.2 rmind * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 1.2.2.2 rmind * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 1.2.2.2 rmind * SUCH DAMAGE. 30 1.2.2.2 rmind */ 31 1.2.2.2 rmind 32 1.2.2.2 rmind /*- 33 1.2.2.2 rmind * Copyright (c) 2010 The NetBSD Foundation, Inc. 34 1.2.2.2 rmind * All rights reserved. 35 1.2.2.2 rmind * 36 1.2.2.2 rmind * This code is derived from software contributed to The NetBSD Foundation 37 1.2.2.2 rmind * by Public Access Networks Corporation ("Panix"). It was developed under 38 1.2.2.2 rmind * contract to Panix by Eric Haszlakiewicz and Thor Lancelot Simon. 39 1.2.2.2 rmind * 40 1.2.2.2 rmind * This code is derived from software contributed to The NetBSD Foundation 41 1.2.2.2 rmind * by Jason R. Thorpe of Zembu Labs, Inc. 42 1.2.2.2 rmind * 43 1.2.2.2 rmind * This code is derived from software contributed to The NetBSD Foundation 44 1.2.2.2 rmind * by Mihai Chelaru <kefren (at) NetBSD.org> 45 1.2.2.2 rmind * 46 1.2.2.2 rmind * Redistribution and use in source and binary forms, with or without 47 1.2.2.2 rmind * modification, are permitted provided that the following conditions 48 1.2.2.2 rmind * are met: 49 1.2.2.2 rmind * 1. Redistributions of source code must retain the above copyright 50 1.2.2.2 rmind * notice, this list of conditions and the following disclaimer. 51 1.2.2.2 rmind * 2. Redistributions in binary form must reproduce the above copyright 52 1.2.2.2 rmind * notice, this list of conditions and the following disclaimer in the 53 1.2.2.2 rmind * documentation and/or other materials provided with the distribution. 54 1.2.2.2 rmind * 55 1.2.2.2 rmind * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 56 1.2.2.2 rmind * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 57 1.2.2.2 rmind * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 58 1.2.2.2 rmind * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 59 1.2.2.2 rmind * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 60 1.2.2.2 rmind * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 61 1.2.2.2 rmind * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 62 1.2.2.2 rmind * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 63 1.2.2.2 rmind * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 64 1.2.2.2 rmind * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 65 1.2.2.2 rmind * POSSIBILITY OF SUCH DAMAGE. 66 1.2.2.2 rmind */ 67 1.2.2.2 rmind 68 1.2.2.2 rmind /* 69 1.2.2.2 rmind * Copyright (c) 1982, 1986, 1988, 1993 70 1.2.2.2 rmind * The Regents of the University of California. All rights reserved. 71 1.2.2.2 rmind * 72 1.2.2.2 rmind * Redistribution and use in source and binary forms, with or without 73 1.2.2.2 rmind * modification, are permitted provided that the following conditions 74 1.2.2.2 rmind * are met: 75 1.2.2.2 rmind * 1. Redistributions of source code must retain the above copyright 76 1.2.2.2 rmind * notice, this list of conditions and the following disclaimer. 77 1.2.2.2 rmind * 2. Redistributions in binary form must reproduce the above copyright 78 1.2.2.2 rmind * notice, this list of conditions and the following disclaimer in the 79 1.2.2.2 rmind * documentation and/or other materials provided with the distribution. 80 1.2.2.2 rmind * 3. Neither the name of the University nor the names of its contributors 81 1.2.2.2 rmind * may be used to endorse or promote products derived from this software 82 1.2.2.2 rmind * without specific prior written permission. 83 1.2.2.2 rmind * 84 1.2.2.2 rmind * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 85 1.2.2.2 rmind * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 86 1.2.2.2 rmind * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 87 1.2.2.2 rmind * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 88 1.2.2.2 rmind * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 89 1.2.2.2 rmind * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 90 1.2.2.2 rmind * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 91 1.2.2.2 rmind * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 92 1.2.2.2 rmind * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 93 1.2.2.2 rmind * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 94 1.2.2.2 rmind * SUCH DAMAGE. 95 1.2.2.2 rmind * 96 1.2.2.2 rmind * @(#)ip_icmp.c 8.2 (Berkeley) 1/4/94 97 1.2.2.2 rmind */ 98 1.2.2.2 rmind 99 1.2.2.2 rmind #include <sys/cdefs.h> 100 1.2.2.2 rmind __KERNEL_RCSID(0, "$NetBSD: mpls_ttl.c,v 1.2.2.3 2011/03/05 20:56:02 rmind Exp $"); 101 1.2.2.2 rmind 102 1.2.2.2 rmind #include "opt_inet.h" 103 1.2.2.2 rmind #include "opt_mpls.h" 104 1.2.2.2 rmind 105 1.2.2.2 rmind #include <sys/param.h> 106 1.2.2.2 rmind #include <sys/malloc.h> 107 1.2.2.2 rmind #include <sys/mbuf.h> 108 1.2.2.2 rmind #include <sys/errno.h> 109 1.2.2.2 rmind #include <sys/socket.h> 110 1.2.2.2 rmind #include <sys/systm.h> 111 1.2.2.2 rmind 112 1.2.2.2 rmind #include <net/if.h> 113 1.2.2.2 rmind #include <net/if_dl.h> 114 1.2.2.2 rmind #include <net/route.h> 115 1.2.2.2 rmind 116 1.2.2.2 rmind #include <netinet/in.h> 117 1.2.2.2 rmind #include <netinet/in_systm.h> 118 1.2.2.2 rmind #include <netinet/ip.h> 119 1.2.2.2 rmind #include <netinet/ip_icmp.h> 120 1.2.2.2 rmind #include <netinet/icmp_private.h> 121 1.2.2.2 rmind #include <netinet/icmp_var.h> 122 1.2.2.2 rmind 123 1.2.2.2 rmind #include <netmpls/mpls.h> 124 1.2.2.2 rmind #include <netmpls/mpls_var.h> 125 1.2.2.2 rmind 126 1.2.2.2 rmind #ifdef INET 127 1.2.2.2 rmind 128 1.2.2.2 rmind /* in netinet/ip_icmp.c */ 129 1.2.2.2 rmind extern int icmpreturndatabytes; 130 1.2.2.2 rmind 131 1.2.2.2 rmind /* ICMP Extensions */ 132 1.2.2.2 rmind 133 1.2.2.2 rmind #define ICMP_EXT_VERSION 2 134 1.2.2.2 rmind #define MPLS_RETURN_DATA 128 135 1.2.2.2 rmind #define ICMP_EXT_OFFSET 128 136 1.2.2.2 rmind 137 1.2.2.2 rmind struct icmp_ext_cmn_hdr { 138 1.2.2.2 rmind #if BYTE_ORDER == BIG_ENDIAN 139 1.2.2.2 rmind unsigned char version:4; 140 1.2.2.2 rmind unsigned char reserved1:4; 141 1.2.2.2 rmind #else 142 1.2.2.2 rmind unsigned char reserved1:4; 143 1.2.2.2 rmind unsigned char version:4; 144 1.2.2.2 rmind #endif 145 1.2.2.2 rmind unsigned char reserved2; 146 1.2.2.2 rmind unsigned short checksum; 147 1.2.2.2 rmind }; 148 1.2.2.2 rmind 149 1.2.2.2 rmind struct icmp_ext_obj_hdr { 150 1.2.2.2 rmind u_short length; 151 1.2.2.2 rmind u_char class_num; 152 1.2.2.2 rmind #define MPLS_STACK_ENTRY_CLASS 1 153 1.2.2.2 rmind u_char c_type; 154 1.2.2.2 rmind #define MPLS_STACK_ENTRY_C_TYPE 1 155 1.2.2.2 rmind }; 156 1.2.2.2 rmind 157 1.2.2.2 rmind struct mpls_extension { 158 1.2.2.2 rmind struct icmp_ext_cmn_hdr cmn_hdr; 159 1.2.2.2 rmind struct icmp_ext_obj_hdr obj_hdr; 160 1.2.2.2 rmind union mpls_shim ms; 161 1.2.2.2 rmind } __packed; 162 1.2.2.2 rmind 163 1.2.2.3 rmind static void mpls_icmp_error(struct mbuf *, int, int, n_long, int, 164 1.2.2.3 rmind union mpls_shim *); 165 1.2.2.3 rmind static bool ip4_check(struct mbuf *); 166 1.2.2.2 rmind 167 1.2.2.2 rmind /* 168 1.2.2.3 rmind * Reference: http://tools.ietf.org/html/rfc4950 169 1.2.2.2 rmind * This should be in sync with icmp_error() in sys/netinet/ip_icmp.c 170 1.2.2.2 rmind */ 171 1.2.2.2 rmind 172 1.2.2.2 rmind static void 173 1.2.2.2 rmind mpls_icmp_error(struct mbuf *n, int type, int code, n_long dest, 174 1.2.2.2 rmind int destmtu, union mpls_shim *shim) 175 1.2.2.2 rmind { 176 1.2.2.2 rmind struct ip *oip = mtod(n, struct ip *), *nip; 177 1.2.2.2 rmind unsigned oiplen = oip->ip_hl << 2; 178 1.2.2.2 rmind struct icmp *icp; 179 1.2.2.2 rmind struct mbuf *m; 180 1.2.2.2 rmind unsigned icmplen, mblen, packetlen; 181 1.2.2.2 rmind struct mpls_extension mpls_icmp_ext; 182 1.2.2.2 rmind 183 1.2.2.2 rmind memset(&mpls_icmp_ext, 0, sizeof(mpls_icmp_ext)); 184 1.2.2.2 rmind mpls_icmp_ext.cmn_hdr.version = ICMP_EXT_VERSION; 185 1.2.2.2 rmind mpls_icmp_ext.cmn_hdr.checksum = 0; 186 1.2.2.2 rmind 187 1.2.2.2 rmind mpls_icmp_ext.obj_hdr.length = htons(sizeof(union mpls_shim) + 188 1.2.2.2 rmind sizeof(struct icmp_ext_obj_hdr)); 189 1.2.2.2 rmind mpls_icmp_ext.obj_hdr.class_num = MPLS_STACK_ENTRY_CLASS; 190 1.2.2.2 rmind mpls_icmp_ext.obj_hdr.c_type = MPLS_STACK_ENTRY_C_TYPE; 191 1.2.2.2 rmind 192 1.2.2.2 rmind mpls_icmp_ext.ms.s_addr = shim->s_addr; 193 1.2.2.2 rmind 194 1.2.2.2 rmind #ifdef ICMPPRINTFS 195 1.2.2.2 rmind if (icmpprintfs) 196 1.2.2.2 rmind printf("mpls_icmp_error(%p, type:%d, code:%d)\n", oip, type, 197 1.2.2.2 rmind code); 198 1.2.2.2 rmind #endif 199 1.2.2.2 rmind if (type != ICMP_REDIRECT) 200 1.2.2.2 rmind ICMP_STATINC(ICMP_STAT_ERROR); 201 1.2.2.2 rmind /* 202 1.2.2.2 rmind * Don't send error if the original packet was encrypted. 203 1.2.2.2 rmind * Don't send error if not the first fragment of message. 204 1.2.2.2 rmind * Don't error if the old packet protocol was ICMP 205 1.2.2.2 rmind * error message, only known informational types. 206 1.2.2.2 rmind */ 207 1.2.2.2 rmind if (n->m_flags & M_DECRYPTED) 208 1.2.2.2 rmind goto freeit; 209 1.2.2.2 rmind if (oip->ip_off &~ htons(IP_MF|IP_DF)) 210 1.2.2.2 rmind goto freeit; 211 1.2.2.2 rmind if (oip->ip_p == IPPROTO_ICMP && type != ICMP_REDIRECT && 212 1.2.2.2 rmind n->m_len >= oiplen + ICMP_MINLEN && 213 1.2.2.2 rmind !ICMP_INFOTYPE(((struct icmp *)((char *)oip + oiplen))->icmp_type)) 214 1.2.2.2 rmind { 215 1.2.2.2 rmind ICMP_STATINC(ICMP_STAT_OLDICMP); 216 1.2.2.2 rmind goto freeit; 217 1.2.2.2 rmind } 218 1.2.2.2 rmind /* Don't send error in response to a multicast or broadcast packet */ 219 1.2.2.2 rmind if (n->m_flags & (M_BCAST|M_MCAST)) 220 1.2.2.2 rmind goto freeit; 221 1.2.2.2 rmind 222 1.2.2.2 rmind /* 223 1.2.2.2 rmind * First, do a rate limitation check. 224 1.2.2.2 rmind */ 225 1.2.2.2 rmind if (icmp_ratelimit(&oip->ip_src, type, code)) 226 1.2.2.2 rmind /* XXX stats */ 227 1.2.2.2 rmind goto freeit; 228 1.2.2.2 rmind 229 1.2.2.2 rmind /* 230 1.2.2.2 rmind * Now, formulate icmp message 231 1.2.2.2 rmind */ 232 1.2.2.2 rmind icmplen = min(ICMP_EXT_OFFSET, ntohs(oip->ip_len)); 233 1.2.2.2 rmind /* 234 1.2.2.2 rmind * Defend against mbuf chains shorter than oip->ip_len - oiplen: 235 1.2.2.2 rmind */ 236 1.2.2.2 rmind mblen = 0; 237 1.2.2.2 rmind for (m = n; m && (mblen < icmplen); m = m->m_next) 238 1.2.2.2 rmind mblen += m->m_len; 239 1.2.2.2 rmind icmplen = min(mblen, icmplen); 240 1.2.2.2 rmind 241 1.2.2.2 rmind packetlen = sizeof(struct ip) + ICMP_EXT_OFFSET + sizeof(mpls_icmp_ext); 242 1.2.2.2 rmind 243 1.2.2.2 rmind /* 244 1.2.2.2 rmind * As we are not required to return everything we have, 245 1.2.2.2 rmind * we return whatever we can return at ease. 246 1.2.2.2 rmind * 247 1.2.2.2 rmind * Note that ICMP datagrams longer than 576 octets are out of spec 248 1.2.2.2 rmind * according to RFC1812; the limit on icmpreturndatabytes below in 249 1.2.2.2 rmind * icmp_sysctl will keep things below that limit. 250 1.2.2.2 rmind */ 251 1.2.2.2 rmind 252 1.2.2.2 rmind KASSERT (packetlen <= MCLBYTES); 253 1.2.2.2 rmind 254 1.2.2.2 rmind m = m_gethdr(M_DONTWAIT, MT_HEADER); 255 1.2.2.2 rmind if (m && (packetlen > MHLEN)) { 256 1.2.2.2 rmind MCLGET(m, M_DONTWAIT); 257 1.2.2.2 rmind if ((m->m_flags & M_EXT) == 0) { 258 1.2.2.2 rmind m_freem(m); 259 1.2.2.2 rmind m = NULL; 260 1.2.2.2 rmind } 261 1.2.2.2 rmind } 262 1.2.2.2 rmind if (m == NULL) 263 1.2.2.2 rmind goto freeit; 264 1.2.2.2 rmind MCLAIM(m, n->m_owner); 265 1.2.2.2 rmind m->m_len = packetlen; 266 1.2.2.2 rmind if ((m->m_flags & M_EXT) == 0) 267 1.2.2.2 rmind MH_ALIGN(m, m->m_len); 268 1.2.2.2 rmind else { 269 1.2.2.2 rmind m->m_data += sizeof(struct ip); 270 1.2.2.2 rmind m->m_len -= sizeof(struct ip); 271 1.2.2.2 rmind } 272 1.2.2.2 rmind icp = mtod(m, struct icmp *); 273 1.2.2.2 rmind if ((u_int)type > ICMP_MAXTYPE) 274 1.2.2.2 rmind panic("icmp error"); 275 1.2.2.2 rmind ICMP_STATINC(ICMP_STAT_OUTHIST + type); 276 1.2.2.2 rmind icp->icmp_type = type; 277 1.2.2.2 rmind if (type == ICMP_REDIRECT) 278 1.2.2.2 rmind icp->icmp_gwaddr.s_addr = dest; 279 1.2.2.2 rmind else { 280 1.2.2.2 rmind icp->icmp_void = 0; 281 1.2.2.2 rmind /* 282 1.2.2.2 rmind * The following assignments assume an overlay with the 283 1.2.2.2 rmind * zeroed icmp_void field. 284 1.2.2.2 rmind */ 285 1.2.2.2 rmind if (type == ICMP_PARAMPROB) { 286 1.2.2.2 rmind icp->icmp_pptr = code; 287 1.2.2.2 rmind code = 0; 288 1.2.2.2 rmind } else if (type == ICMP_UNREACH && 289 1.2.2.2 rmind code == ICMP_UNREACH_NEEDFRAG && destmtu) 290 1.2.2.2 rmind icp->icmp_nextmtu = htons(destmtu); 291 1.2.2.2 rmind } 292 1.2.2.2 rmind 293 1.2.2.2 rmind icp->icmp_code = code; 294 1.2.2.2 rmind 295 1.2.2.2 rmind memset(&icp->icmp_ip, 0, ICMP_EXT_OFFSET); 296 1.2.2.2 rmind m_copydata(n, 0, icmplen, (char *)&icp->icmp_ip); 297 1.2.2.2 rmind 298 1.2.2.2 rmind /* Append the extension structure */ 299 1.2.2.2 rmind memcpy(((char*)&icp->icmp_ip) + ICMP_EXT_OFFSET, 300 1.2.2.2 rmind &mpls_icmp_ext, sizeof(mpls_icmp_ext)); 301 1.2.2.2 rmind 302 1.2.2.2 rmind /* 303 1.2.2.2 rmind * Now, copy old ip header (without options) 304 1.2.2.2 rmind * in front of icmp message. 305 1.2.2.2 rmind */ 306 1.2.2.2 rmind if ((m->m_flags & M_EXT) == 0 && 307 1.2.2.2 rmind m->m_data - sizeof(struct ip) < m->m_pktdat) 308 1.2.2.2 rmind panic("icmp len"); 309 1.2.2.2 rmind m->m_data -= sizeof(struct ip); 310 1.2.2.2 rmind m->m_len += sizeof(struct ip); 311 1.2.2.2 rmind m->m_pkthdr.len = m->m_len; 312 1.2.2.2 rmind m->m_pkthdr.rcvif = n->m_pkthdr.rcvif; 313 1.2.2.2 rmind nip = mtod(m, struct ip *); 314 1.2.2.2 rmind /* ip_v set in ip_output */ 315 1.2.2.2 rmind nip->ip_hl = sizeof(struct ip) >> 2; 316 1.2.2.2 rmind nip->ip_tos = 0; 317 1.2.2.2 rmind nip->ip_len = htons(m->m_len); 318 1.2.2.2 rmind /* ip_id set in ip_output */ 319 1.2.2.2 rmind nip->ip_off = htons(0); 320 1.2.2.2 rmind /* ip_ttl set in icmp_reflect */ 321 1.2.2.2 rmind nip->ip_p = IPPROTO_ICMP; 322 1.2.2.2 rmind nip->ip_src = oip->ip_src; 323 1.2.2.2 rmind nip->ip_dst = oip->ip_dst; 324 1.2.2.2 rmind icmp_reflect(m); 325 1.2.2.2 rmind 326 1.2.2.2 rmind freeit: 327 1.2.2.2 rmind m_freem(n); 328 1.2.2.2 rmind 329 1.2.2.2 rmind } 330 1.2.2.2 rmind 331 1.2.2.3 rmind static bool 332 1.2.2.3 rmind ip4_check(struct mbuf *m) 333 1.2.2.3 rmind { 334 1.2.2.3 rmind struct ip *iph; 335 1.2.2.3 rmind int hlen, len; 336 1.2.2.3 rmind 337 1.2.2.3 rmind if (m->m_len < sizeof(struct ip) && 338 1.2.2.3 rmind (m = m_pullup(m, sizeof(struct ip))) == NULL) 339 1.2.2.3 rmind return false; 340 1.2.2.3 rmind 341 1.2.2.3 rmind iph = mtod(m, struct ip *); 342 1.2.2.3 rmind 343 1.2.2.3 rmind if (iph->ip_v != IPVERSION) 344 1.2.2.3 rmind goto freeit; 345 1.2.2.3 rmind hlen = iph->ip_hl << 2; 346 1.2.2.3 rmind if (hlen < sizeof(struct ip)) 347 1.2.2.3 rmind goto freeit; 348 1.2.2.3 rmind if (hlen > m->m_len) { 349 1.2.2.3 rmind if ((m = m_pullup(m, hlen)) == NULL) 350 1.2.2.3 rmind return false; 351 1.2.2.3 rmind iph = mtod(m, struct ip *); 352 1.2.2.3 rmind } 353 1.2.2.3 rmind if (IN_MULTICAST(iph->ip_src.s_addr) || 354 1.2.2.3 rmind (ntohl(iph->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET || 355 1.2.2.3 rmind (ntohl(iph->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET || 356 1.2.2.3 rmind in_cksum(m, hlen) != 0) 357 1.2.2.3 rmind goto freeit; 358 1.2.2.3 rmind 359 1.2.2.3 rmind len = ntohs(iph->ip_len); 360 1.2.2.3 rmind if (len < hlen || m->m_pkthdr.len < len) 361 1.2.2.3 rmind goto freeit; 362 1.2.2.3 rmind 363 1.2.2.3 rmind return true; 364 1.2.2.3 rmind freeit: 365 1.2.2.3 rmind m_freem(m); 366 1.2.2.3 rmind return false; 367 1.2.2.3 rmind 368 1.2.2.3 rmind } 369 1.2.2.3 rmind 370 1.2.2.2 rmind #endif /* INET */ 371 1.2.2.2 rmind 372 1.2.2.2 rmind struct mbuf * 373 1.2.2.2 rmind mpls_ttl_dec(struct mbuf *m) 374 1.2.2.2 rmind { 375 1.2.2.2 rmind union mpls_shim *mshim; 376 1.2.2.2 rmind #ifdef INET 377 1.2.2.2 rmind union mpls_shim top_shim, bossh; 378 1.2.2.2 rmind #endif 379 1.2.2.2 rmind 380 1.2.2.2 rmind if (m->m_len < sizeof(union mpls_shim) && 381 1.2.2.2 rmind (m = m_pullup(m, sizeof(union mpls_shim))) == NULL) 382 1.2.2.2 rmind return NULL; 383 1.2.2.2 rmind mshim = mtod(m, union mpls_shim *); 384 1.2.2.2 rmind mshim->s_addr = ntohl(mshim->s_addr); 385 1.2.2.2 rmind mshim->shim.ttl--; 386 1.2.2.2 rmind 387 1.2.2.2 rmind if (mshim->shim.ttl == 0) { 388 1.2.2.2 rmind if (!mpls_icmp_respond) { 389 1.2.2.2 rmind m_freem(m); 390 1.2.2.2 rmind return NULL; 391 1.2.2.2 rmind } 392 1.2.2.2 rmind 393 1.2.2.2 rmind #ifdef INET 394 1.2.2.2 rmind /* 395 1.2.2.2 rmind * shim ttl exceeded 396 1.2.2.2 rmind * send back ICMP type 11 code 0 397 1.2.2.2 rmind */ 398 1.2.2.2 rmind bossh.s_addr = mshim->s_addr; 399 1.2.2.2 rmind top_shim.s_addr = htonl(mshim->s_addr); 400 1.2.2.2 rmind m_adj(m, sizeof(union mpls_shim)); 401 1.2.2.2 rmind 402 1.2.2.2 rmind /* Goto BOS */ 403 1.2.2.2 rmind while(bossh.shim.bos == 0) { 404 1.2.2.2 rmind if (m->m_len < sizeof(union mpls_shim) && 405 1.2.2.2 rmind (m = m_pullup(m, sizeof(union mpls_shim))) == NULL) { 406 1.2.2.2 rmind m_freem(m); 407 1.2.2.2 rmind return NULL; 408 1.2.2.2 rmind } 409 1.2.2.2 rmind bossh.s_addr = ntohl(mtod(m, union mpls_shim *)->s_addr); 410 1.2.2.2 rmind m_adj(m, sizeof(union mpls_shim)); 411 1.2.2.2 rmind } 412 1.2.2.3 rmind 413 1.2.2.3 rmind if (ip4_check(m) == true) 414 1.2.2.3 rmind mpls_icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, 415 1.2.2.3 rmind 0, 0, &top_shim); 416 1.2.2.2 rmind #else 417 1.2.2.2 rmind m_freem(m); 418 1.2.2.2 rmind #endif 419 1.2.2.2 rmind return NULL; 420 1.2.2.2 rmind } 421 1.2.2.2 rmind 422 1.2.2.2 rmind mshim->s_addr = htonl(mshim->s_addr); 423 1.2.2.2 rmind 424 1.2.2.2 rmind return m; 425 1.2.2.2 rmind } 426
Indexes created Mon Sep 22 21:09:42 GMT 2025