mpls_ttl.c revision 1.3.2.2
1 1.3.2.2 yamt /* $NetBSD: mpls_ttl.c,v 1.3.2.2 2010/08/11 22:54:58 yamt Exp $ */ 2 1.3.2.2 yamt 3 1.3.2.2 yamt /* 4 1.3.2.2 yamt * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 5 1.3.2.2 yamt * All rights reserved. 6 1.3.2.2 yamt * 7 1.3.2.2 yamt * Redistribution and use in source and binary forms, with or without 8 1.3.2.2 yamt * modification, are permitted provided that the following conditions 9 1.3.2.2 yamt * are met: 10 1.3.2.2 yamt * 1. Redistributions of source code must retain the above copyright 11 1.3.2.2 yamt * notice, this list of conditions and the following disclaimer. 12 1.3.2.2 yamt * 2. Redistributions in binary form must reproduce the above copyright 13 1.3.2.2 yamt * notice, this list of conditions and the following disclaimer in the 14 1.3.2.2 yamt * documentation and/or other materials provided with the distribution. 15 1.3.2.2 yamt * 3. Neither the name of the project nor the names of its contributors 16 1.3.2.2 yamt * may be used to endorse or promote products derived from this software 17 1.3.2.2 yamt * without specific prior written permission. 18 1.3.2.2 yamt * 19 1.3.2.2 yamt * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 20 1.3.2.2 yamt * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 1.3.2.2 yamt * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 1.3.2.2 yamt * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 23 1.3.2.2 yamt * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 1.3.2.2 yamt * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 1.3.2.2 yamt * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 1.3.2.2 yamt * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 1.3.2.2 yamt * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 1.3.2.2 yamt * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 1.3.2.2 yamt * SUCH DAMAGE. 30 1.3.2.2 yamt */ 31 1.3.2.2 yamt 32 1.3.2.2 yamt /*- 33 1.3.2.2 yamt * Copyright (c) 2010 The NetBSD Foundation, Inc. 34 1.3.2.2 yamt * All rights reserved. 35 1.3.2.2 yamt * 36 1.3.2.2 yamt * This code is derived from software contributed to The NetBSD Foundation 37 1.3.2.2 yamt * by Public Access Networks Corporation ("Panix"). It was developed under 38 1.3.2.2 yamt * contract to Panix by Eric Haszlakiewicz and Thor Lancelot Simon. 39 1.3.2.2 yamt * 40 1.3.2.2 yamt * This code is derived from software contributed to The NetBSD Foundation 41 1.3.2.2 yamt * by Jason R. Thorpe of Zembu Labs, Inc. 42 1.3.2.2 yamt * 43 1.3.2.2 yamt * This code is derived from software contributed to The NetBSD Foundation 44 1.3.2.2 yamt * by Mihai Chelaru <kefren (at) NetBSD.org> 45 1.3.2.2 yamt * 46 1.3.2.2 yamt * Redistribution and use in source and binary forms, with or without 47 1.3.2.2 yamt * modification, are permitted provided that the following conditions 48 1.3.2.2 yamt * are met: 49 1.3.2.2 yamt * 1. Redistributions of source code must retain the above copyright 50 1.3.2.2 yamt * notice, this list of conditions and the following disclaimer. 51 1.3.2.2 yamt * 2. Redistributions in binary form must reproduce the above copyright 52 1.3.2.2 yamt * notice, this list of conditions and the following disclaimer in the 53 1.3.2.2 yamt * documentation and/or other materials provided with the distribution. 54 1.3.2.2 yamt * 55 1.3.2.2 yamt * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 56 1.3.2.2 yamt * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 57 1.3.2.2 yamt * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 58 1.3.2.2 yamt * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 59 1.3.2.2 yamt * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 60 1.3.2.2 yamt * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 61 1.3.2.2 yamt * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 62 1.3.2.2 yamt * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 63 1.3.2.2 yamt * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 64 1.3.2.2 yamt * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 65 1.3.2.2 yamt * POSSIBILITY OF SUCH DAMAGE. 66 1.3.2.2 yamt */ 67 1.3.2.2 yamt 68 1.3.2.2 yamt /* 69 1.3.2.2 yamt * Copyright (c) 1982, 1986, 1988, 1993 70 1.3.2.2 yamt * The Regents of the University of California. All rights reserved. 71 1.3.2.2 yamt * 72 1.3.2.2 yamt * Redistribution and use in source and binary forms, with or without 73 1.3.2.2 yamt * modification, are permitted provided that the following conditions 74 1.3.2.2 yamt * are met: 75 1.3.2.2 yamt * 1. Redistributions of source code must retain the above copyright 76 1.3.2.2 yamt * notice, this list of conditions and the following disclaimer. 77 1.3.2.2 yamt * 2. Redistributions in binary form must reproduce the above copyright 78 1.3.2.2 yamt * notice, this list of conditions and the following disclaimer in the 79 1.3.2.2 yamt * documentation and/or other materials provided with the distribution. 80 1.3.2.2 yamt * 3. Neither the name of the University nor the names of its contributors 81 1.3.2.2 yamt * may be used to endorse or promote products derived from this software 82 1.3.2.2 yamt * without specific prior written permission. 83 1.3.2.2 yamt * 84 1.3.2.2 yamt * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 85 1.3.2.2 yamt * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 86 1.3.2.2 yamt * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 87 1.3.2.2 yamt * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 88 1.3.2.2 yamt * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 89 1.3.2.2 yamt * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 90 1.3.2.2 yamt * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 91 1.3.2.2 yamt * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 92 1.3.2.2 yamt * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 93 1.3.2.2 yamt * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 94 1.3.2.2 yamt * SUCH DAMAGE. 95 1.3.2.2 yamt * 96 1.3.2.2 yamt * @(#)ip_icmp.c 8.2 (Berkeley) 1/4/94 97 1.3.2.2 yamt */ 98 1.3.2.2 yamt 99 1.3.2.2 yamt #include <sys/cdefs.h> 100 1.3.2.2 yamt __KERNEL_RCSID(0, "$NetBSD: mpls_ttl.c,v 1.3.2.2 2010/08/11 22:54:58 yamt Exp $"); 101 1.3.2.2 yamt 102 1.3.2.2 yamt #include "opt_inet.h" 103 1.3.2.2 yamt #include "opt_mpls.h" 104 1.3.2.2 yamt 105 1.3.2.2 yamt #include <sys/param.h> 106 1.3.2.2 yamt #include <sys/malloc.h> 107 1.3.2.2 yamt #include <sys/mbuf.h> 108 1.3.2.2 yamt #include <sys/errno.h> 109 1.3.2.2 yamt #include <sys/socket.h> 110 1.3.2.2 yamt #include <sys/systm.h> 111 1.3.2.2 yamt 112 1.3.2.2 yamt #include <net/if.h> 113 1.3.2.2 yamt #include <net/if_dl.h> 114 1.3.2.2 yamt #include <net/route.h> 115 1.3.2.2 yamt 116 1.3.2.2 yamt #include <netinet/in.h> 117 1.3.2.2 yamt #include <netinet/in_systm.h> 118 1.3.2.2 yamt #include <netinet/ip.h> 119 1.3.2.2 yamt #include <netinet/ip_icmp.h> 120 1.3.2.2 yamt #include <netinet/icmp_private.h> 121 1.3.2.2 yamt #include <netinet/icmp_var.h> 122 1.3.2.2 yamt 123 1.3.2.2 yamt #include <netmpls/mpls.h> 124 1.3.2.2 yamt #include <netmpls/mpls_var.h> 125 1.3.2.2 yamt 126 1.3.2.2 yamt #ifdef INET 127 1.3.2.2 yamt 128 1.3.2.2 yamt /* in netinet/ip_icmp.c */ 129 1.3.2.2 yamt extern int icmpreturndatabytes; 130 1.3.2.2 yamt 131 1.3.2.2 yamt /* ICMP Extensions */ 132 1.3.2.2 yamt 133 1.3.2.2 yamt #define ICMP_EXT_VERSION 2 134 1.3.2.2 yamt #define MPLS_RETURN_DATA 128 135 1.3.2.2 yamt #define ICMP_EXT_OFFSET 128 136 1.3.2.2 yamt 137 1.3.2.2 yamt struct icmp_ext_cmn_hdr { 138 1.3.2.2 yamt #if BYTE_ORDER == BIG_ENDIAN 139 1.3.2.2 yamt unsigned char version:4; 140 1.3.2.2 yamt unsigned char reserved1:4; 141 1.3.2.2 yamt #else 142 1.3.2.2 yamt unsigned char reserved1:4; 143 1.3.2.2 yamt unsigned char version:4; 144 1.3.2.2 yamt #endif 145 1.3.2.2 yamt unsigned char reserved2; 146 1.3.2.2 yamt unsigned short checksum; 147 1.3.2.2 yamt }; 148 1.3.2.2 yamt 149 1.3.2.2 yamt struct icmp_ext_obj_hdr { 150 1.3.2.2 yamt u_short length; 151 1.3.2.2 yamt u_char class_num; 152 1.3.2.2 yamt #define MPLS_STACK_ENTRY_CLASS 1 153 1.3.2.2 yamt u_char c_type; 154 1.3.2.2 yamt #define MPLS_STACK_ENTRY_C_TYPE 1 155 1.3.2.2 yamt }; 156 1.3.2.2 yamt 157 1.3.2.2 yamt struct mpls_extension { 158 1.3.2.2 yamt struct icmp_ext_cmn_hdr cmn_hdr; 159 1.3.2.2 yamt struct icmp_ext_obj_hdr obj_hdr; 160 1.3.2.2 yamt union mpls_shim ms; 161 1.3.2.2 yamt } __packed; 162 1.3.2.2 yamt 163 1.3.2.2 yamt static void mpls_icmp_error(struct mbuf *, int, int, n_long, int, 164 1.3.2.2 yamt union mpls_shim *); 165 1.3.2.2 yamt static bool ip4_check(struct mbuf *); 166 1.3.2.2 yamt 167 1.3.2.2 yamt /* 168 1.3.2.2 yamt * Reference: http://tools.ietf.org/html/rfc4950 169 1.3.2.2 yamt * This should be in sync with icmp_error() in sys/netinet/ip_icmp.c 170 1.3.2.2 yamt */ 171 1.3.2.2 yamt 172 1.3.2.2 yamt static void 173 1.3.2.2 yamt mpls_icmp_error(struct mbuf *n, int type, int code, n_long dest, 174 1.3.2.2 yamt int destmtu, union mpls_shim *shim) 175 1.3.2.2 yamt { 176 1.3.2.2 yamt struct ip *oip = mtod(n, struct ip *), *nip; 177 1.3.2.2 yamt unsigned oiplen = oip->ip_hl << 2; 178 1.3.2.2 yamt struct icmp *icp; 179 1.3.2.2 yamt struct mbuf *m; 180 1.3.2.2 yamt unsigned icmplen, mblen, packetlen; 181 1.3.2.2 yamt struct mpls_extension mpls_icmp_ext; 182 1.3.2.2 yamt 183 1.3.2.2 yamt memset(&mpls_icmp_ext, 0, sizeof(mpls_icmp_ext)); 184 1.3.2.2 yamt mpls_icmp_ext.cmn_hdr.version = ICMP_EXT_VERSION; 185 1.3.2.2 yamt mpls_icmp_ext.cmn_hdr.checksum = 0; 186 1.3.2.2 yamt 187 1.3.2.2 yamt mpls_icmp_ext.obj_hdr.length = htons(sizeof(union mpls_shim) + 188 1.3.2.2 yamt sizeof(struct icmp_ext_obj_hdr)); 189 1.3.2.2 yamt mpls_icmp_ext.obj_hdr.class_num = MPLS_STACK_ENTRY_CLASS; 190 1.3.2.2 yamt mpls_icmp_ext.obj_hdr.c_type = MPLS_STACK_ENTRY_C_TYPE; 191 1.3.2.2 yamt 192 1.3.2.2 yamt mpls_icmp_ext.ms.s_addr = shim->s_addr; 193 1.3.2.2 yamt 194 1.3.2.2 yamt #ifdef ICMPPRINTFS 195 1.3.2.2 yamt if (icmpprintfs) 196 1.3.2.2 yamt printf("mpls_icmp_error(%p, type:%d, code:%d)\n", oip, type, 197 1.3.2.2 yamt code); 198 1.3.2.2 yamt #endif 199 1.3.2.2 yamt if (type != ICMP_REDIRECT) 200 1.3.2.2 yamt ICMP_STATINC(ICMP_STAT_ERROR); 201 1.3.2.2 yamt /* 202 1.3.2.2 yamt * Don't send error if the original packet was encrypted. 203 1.3.2.2 yamt * Don't send error if not the first fragment of message. 204 1.3.2.2 yamt * Don't error if the old packet protocol was ICMP 205 1.3.2.2 yamt * error message, only known informational types. 206 1.3.2.2 yamt */ 207 1.3.2.2 yamt if (n->m_flags & M_DECRYPTED) 208 1.3.2.2 yamt goto freeit; 209 1.3.2.2 yamt if (oip->ip_off &~ htons(IP_MF|IP_DF)) 210 1.3.2.2 yamt goto freeit; 211 1.3.2.2 yamt if (oip->ip_p == IPPROTO_ICMP && type != ICMP_REDIRECT && 212 1.3.2.2 yamt n->m_len >= oiplen + ICMP_MINLEN && 213 1.3.2.2 yamt !ICMP_INFOTYPE(((struct icmp *)((char *)oip + oiplen))->icmp_type)) 214 1.3.2.2 yamt { 215 1.3.2.2 yamt ICMP_STATINC(ICMP_STAT_OLDICMP); 216 1.3.2.2 yamt goto freeit; 217 1.3.2.2 yamt } 218 1.3.2.2 yamt /* Don't send error in response to a multicast or broadcast packet */ 219 1.3.2.2 yamt if (n->m_flags & (M_BCAST|M_MCAST)) 220 1.3.2.2 yamt goto freeit; 221 1.3.2.2 yamt 222 1.3.2.2 yamt /* 223 1.3.2.2 yamt * First, do a rate limitation check. 224 1.3.2.2 yamt */ 225 1.3.2.2 yamt if (icmp_ratelimit(&oip->ip_src, type, code)) 226 1.3.2.2 yamt /* XXX stats */ 227 1.3.2.2 yamt goto freeit; 228 1.3.2.2 yamt 229 1.3.2.2 yamt /* 230 1.3.2.2 yamt * Now, formulate icmp message 231 1.3.2.2 yamt */ 232 1.3.2.2 yamt icmplen = min(ICMP_EXT_OFFSET, ntohs(oip->ip_len)); 233 1.3.2.2 yamt /* 234 1.3.2.2 yamt * Defend against mbuf chains shorter than oip->ip_len - oiplen: 235 1.3.2.2 yamt */ 236 1.3.2.2 yamt mblen = 0; 237 1.3.2.2 yamt for (m = n; m && (mblen < icmplen); m = m->m_next) 238 1.3.2.2 yamt mblen += m->m_len; 239 1.3.2.2 yamt icmplen = min(mblen, icmplen); 240 1.3.2.2 yamt 241 1.3.2.2 yamt packetlen = sizeof(struct ip) + ICMP_EXT_OFFSET + sizeof(mpls_icmp_ext); 242 1.3.2.2 yamt 243 1.3.2.2 yamt /* 244 1.3.2.2 yamt * As we are not required to return everything we have, 245 1.3.2.2 yamt * we return whatever we can return at ease. 246 1.3.2.2 yamt * 247 1.3.2.2 yamt * Note that ICMP datagrams longer than 576 octets are out of spec 248 1.3.2.2 yamt * according to RFC1812; the limit on icmpreturndatabytes below in 249 1.3.2.2 yamt * icmp_sysctl will keep things below that limit. 250 1.3.2.2 yamt */ 251 1.3.2.2 yamt 252 1.3.2.2 yamt KASSERT (packetlen <= MCLBYTES); 253 1.3.2.2 yamt 254 1.3.2.2 yamt m = m_gethdr(M_DONTWAIT, MT_HEADER); 255 1.3.2.2 yamt if (m && (packetlen > MHLEN)) { 256 1.3.2.2 yamt MCLGET(m, M_DONTWAIT); 257 1.3.2.2 yamt if ((m->m_flags & M_EXT) == 0) { 258 1.3.2.2 yamt m_freem(m); 259 1.3.2.2 yamt m = NULL; 260 1.3.2.2 yamt } 261 1.3.2.2 yamt } 262 1.3.2.2 yamt if (m == NULL) 263 1.3.2.2 yamt goto freeit; 264 1.3.2.2 yamt MCLAIM(m, n->m_owner); 265 1.3.2.2 yamt m->m_len = packetlen; 266 1.3.2.2 yamt if ((m->m_flags & M_EXT) == 0) 267 1.3.2.2 yamt MH_ALIGN(m, m->m_len); 268 1.3.2.2 yamt else { 269 1.3.2.2 yamt m->m_data += sizeof(struct ip); 270 1.3.2.2 yamt m->m_len -= sizeof(struct ip); 271 1.3.2.2 yamt } 272 1.3.2.2 yamt icp = mtod(m, struct icmp *); 273 1.3.2.2 yamt if ((u_int)type > ICMP_MAXTYPE) 274 1.3.2.2 yamt panic("icmp error"); 275 1.3.2.2 yamt ICMP_STATINC(ICMP_STAT_OUTHIST + type); 276 1.3.2.2 yamt icp->icmp_type = type; 277 1.3.2.2 yamt if (type == ICMP_REDIRECT) 278 1.3.2.2 yamt icp->icmp_gwaddr.s_addr = dest; 279 1.3.2.2 yamt else { 280 1.3.2.2 yamt icp->icmp_void = 0; 281 1.3.2.2 yamt /* 282 1.3.2.2 yamt * The following assignments assume an overlay with the 283 1.3.2.2 yamt * zeroed icmp_void field. 284 1.3.2.2 yamt */ 285 1.3.2.2 yamt if (type == ICMP_PARAMPROB) { 286 1.3.2.2 yamt icp->icmp_pptr = code; 287 1.3.2.2 yamt code = 0; 288 1.3.2.2 yamt } else if (type == ICMP_UNREACH && 289 1.3.2.2 yamt code == ICMP_UNREACH_NEEDFRAG && destmtu) 290 1.3.2.2 yamt icp->icmp_nextmtu = htons(destmtu); 291 1.3.2.2 yamt } 292 1.3.2.2 yamt 293 1.3.2.2 yamt icp->icmp_code = code; 294 1.3.2.2 yamt 295 1.3.2.2 yamt memset(&icp->icmp_ip, 0, ICMP_EXT_OFFSET); 296 1.3.2.2 yamt m_copydata(n, 0, icmplen, (char *)&icp->icmp_ip); 297 1.3.2.2 yamt 298 1.3.2.2 yamt /* Append the extension structure */ 299 1.3.2.2 yamt memcpy(((char*)&icp->icmp_ip) + ICMP_EXT_OFFSET, 300 1.3.2.2 yamt &mpls_icmp_ext, sizeof(mpls_icmp_ext)); 301 1.3.2.2 yamt 302 1.3.2.2 yamt /* 303 1.3.2.2 yamt * Now, copy old ip header (without options) 304 1.3.2.2 yamt * in front of icmp message. 305 1.3.2.2 yamt */ 306 1.3.2.2 yamt if ((m->m_flags & M_EXT) == 0 && 307 1.3.2.2 yamt m->m_data - sizeof(struct ip) < m->m_pktdat) 308 1.3.2.2 yamt panic("icmp len"); 309 1.3.2.2 yamt m->m_data -= sizeof(struct ip); 310 1.3.2.2 yamt m->m_len += sizeof(struct ip); 311 1.3.2.2 yamt m->m_pkthdr.len = m->m_len; 312 1.3.2.2 yamt m->m_pkthdr.rcvif = n->m_pkthdr.rcvif; 313 1.3.2.2 yamt nip = mtod(m, struct ip *); 314 1.3.2.2 yamt /* ip_v set in ip_output */ 315 1.3.2.2 yamt nip->ip_hl = sizeof(struct ip) >> 2; 316 1.3.2.2 yamt nip->ip_tos = 0; 317 1.3.2.2 yamt nip->ip_len = htons(m->m_len); 318 1.3.2.2 yamt /* ip_id set in ip_output */ 319 1.3.2.2 yamt nip->ip_off = htons(0); 320 1.3.2.2 yamt /* ip_ttl set in icmp_reflect */ 321 1.3.2.2 yamt nip->ip_p = IPPROTO_ICMP; 322 1.3.2.2 yamt nip->ip_src = oip->ip_src; 323 1.3.2.2 yamt nip->ip_dst = oip->ip_dst; 324 1.3.2.2 yamt icmp_reflect(m); 325 1.3.2.2 yamt 326 1.3.2.2 yamt freeit: 327 1.3.2.2 yamt m_freem(n); 328 1.3.2.2 yamt 329 1.3.2.2 yamt } 330 1.3.2.2 yamt 331 1.3.2.2 yamt static bool 332 1.3.2.2 yamt ip4_check(struct mbuf *m) 333 1.3.2.2 yamt { 334 1.3.2.2 yamt struct ip *iph; 335 1.3.2.2 yamt int hlen, len; 336 1.3.2.2 yamt 337 1.3.2.2 yamt if (m->m_len < sizeof(struct ip) && 338 1.3.2.2 yamt (m = m_pullup(m, sizeof(struct ip))) == NULL) 339 1.3.2.2 yamt return false; 340 1.3.2.2 yamt 341 1.3.2.2 yamt iph = mtod(m, struct ip *); 342 1.3.2.2 yamt 343 1.3.2.2 yamt if (iph->ip_v != IPVERSION) 344 1.3.2.2 yamt goto freeit; 345 1.3.2.2 yamt hlen = iph->ip_hl << 2; 346 1.3.2.2 yamt if (hlen < sizeof(struct ip)) 347 1.3.2.2 yamt goto freeit; 348 1.3.2.2 yamt if (hlen > m->m_len) { 349 1.3.2.2 yamt if ((m = m_pullup(m, hlen)) == NULL) 350 1.3.2.2 yamt return false; 351 1.3.2.2 yamt iph = mtod(m, struct ip *); 352 1.3.2.2 yamt } 353 1.3.2.2 yamt if (IN_MULTICAST(iph->ip_src.s_addr) || 354 1.3.2.2 yamt (ntohl(iph->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET || 355 1.3.2.2 yamt (ntohl(iph->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET || 356 1.3.2.2 yamt in_cksum(m, hlen) != 0) 357 1.3.2.2 yamt goto freeit; 358 1.3.2.2 yamt 359 1.3.2.2 yamt len = ntohs(iph->ip_len); 360 1.3.2.2 yamt if (len < hlen || m->m_pkthdr.len < len) 361 1.3.2.2 yamt goto freeit; 362 1.3.2.2 yamt 363 1.3.2.2 yamt return true; 364 1.3.2.2 yamt freeit: 365 1.3.2.2 yamt m_freem(m); 366 1.3.2.2 yamt return false; 367 1.3.2.2 yamt 368 1.3.2.2 yamt } 369 1.3.2.2 yamt 370 1.3.2.2 yamt #endif /* INET */ 371 1.3.2.2 yamt 372 1.3.2.2 yamt struct mbuf * 373 1.3.2.2 yamt mpls_ttl_dec(struct mbuf *m) 374 1.3.2.2 yamt { 375 1.3.2.2 yamt union mpls_shim *mshim; 376 1.3.2.2 yamt #ifdef INET 377 1.3.2.2 yamt union mpls_shim top_shim, bossh; 378 1.3.2.2 yamt #endif 379 1.3.2.2 yamt 380 1.3.2.2 yamt if (m->m_len < sizeof(union mpls_shim) && 381 1.3.2.2 yamt (m = m_pullup(m, sizeof(union mpls_shim))) == NULL) 382 1.3.2.2 yamt return NULL; 383 1.3.2.2 yamt mshim = mtod(m, union mpls_shim *); 384 1.3.2.2 yamt mshim->s_addr = ntohl(mshim->s_addr); 385 1.3.2.2 yamt mshim->shim.ttl--; 386 1.3.2.2 yamt 387 1.3.2.2 yamt if (mshim->shim.ttl == 0) { 388 1.3.2.2 yamt if (!mpls_icmp_respond) { 389 1.3.2.2 yamt m_freem(m); 390 1.3.2.2 yamt return NULL; 391 1.3.2.2 yamt } 392 1.3.2.2 yamt 393 1.3.2.2 yamt #ifdef INET 394 1.3.2.2 yamt /* 395 1.3.2.2 yamt * shim ttl exceeded 396 1.3.2.2 yamt * send back ICMP type 11 code 0 397 1.3.2.2 yamt */ 398 1.3.2.2 yamt bossh.s_addr = mshim->s_addr; 399 1.3.2.2 yamt top_shim.s_addr = htonl(mshim->s_addr); 400 1.3.2.2 yamt m_adj(m, sizeof(union mpls_shim)); 401 1.3.2.2 yamt 402 1.3.2.2 yamt /* Goto BOS */ 403 1.3.2.2 yamt while(bossh.shim.bos == 0) { 404 1.3.2.2 yamt if (m->m_len < sizeof(union mpls_shim) && 405 1.3.2.2 yamt (m = m_pullup(m, sizeof(union mpls_shim))) == NULL) { 406 1.3.2.2 yamt m_freem(m); 407 1.3.2.2 yamt return NULL; 408 1.3.2.2 yamt } 409 1.3.2.2 yamt bossh.s_addr = ntohl(mtod(m, union mpls_shim *)->s_addr); 410 1.3.2.2 yamt m_adj(m, sizeof(union mpls_shim)); 411 1.3.2.2 yamt } 412 1.3.2.2 yamt 413 1.3.2.2 yamt if (ip4_check(m) == true) 414 1.3.2.2 yamt mpls_icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, 415 1.3.2.2 yamt 0, 0, &top_shim); 416 1.3.2.2 yamt #else 417 1.3.2.2 yamt m_freem(m); 418 1.3.2.2 yamt #endif 419 1.3.2.2 yamt return NULL; 420 1.3.2.2 yamt } 421 1.3.2.2 yamt 422 1.3.2.2 yamt mshim->s_addr = htonl(mshim->s_addr); 423 1.3.2.2 yamt 424 1.3.2.2 yamt return m; 425 1.3.2.2 yamt } 426
Indexes created Mon Sep 22 21:09:42 GMT 2025