1 /* 2 * Copyright (c) 2007 The DragonFly Project. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 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 12 * the documentation and/or other materials provided with the 13 * distribution. 14 * 3. Neither the name of The DragonFly Project nor the names of its 15 * contributors may be used to endorse or promote products derived 16 * from this software without specific, prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 21 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 22 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 23 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 24 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 25 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 26 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 27 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 28 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * $DragonFly: src/sys/netproto/mpls/mpls_demux.c,v 1.2 2008/08/05 15:11:32 nant Exp $ 32 */ 33 34 #include <sys/param.h> 35 #include <sys/mbuf.h> 36 37 #include <net/netisr.h> 38 #include <netinet/in_var.h> 39 40 #include <netproto/mpls/mpls.h> 41 #include <netproto/mpls/mpls_var.h> 42 43 static __inline int 44 MPLSP_MPORT_HASH(mpls_label_t label, u_short if_index) 45 { 46 /* Use low order byte (demux up to 256 cpus) */ 47 KASSERT(netisr_ncpus <= 256, ("need different hash function")); /* XXX */ 48 #if BYTE_ORDER == LITTLE_ENDIAN 49 label &= 0x00ff0000; 50 label = label >> 16; 51 #endif 52 return ((label ^ if_index) % netisr_ncpus); 53 } 54 55 static void 56 mpls_lengthcheck(struct mbuf **mp, int hoff) 57 { 58 struct mbuf *m = *mp; 59 int hlen = hoff + sizeof(struct mpls); 60 61 /* The packet must be at least the size of an MPLS header. */ 62 if (m->m_pkthdr.len < hlen) { 63 mplsstat.mplss_tooshort++; 64 m_free(m); 65 *mp = NULL; 66 return; 67 } 68 69 /* The MPLS header must reside completely in the first mbuf. */ 70 if (m->m_len < hlen) { 71 m = m_pullup(m, hlen); 72 if (m == NULL) { 73 mplsstat.mplss_toosmall++; 74 *mp = NULL; 75 return; 76 } 77 } 78 *mp = m; 79 } 80 81 void 82 mpls_hashfn(struct mbuf **mp, int hoff) 83 { 84 struct mbuf *m = *mp; 85 struct mpls *mpls; 86 mpls_label_t label; 87 struct ifnet *ifp; 88 89 mpls_lengthcheck(mp, hoff); 90 if ((m = *mp) == NULL) 91 return; 92 93 mpls = mtodoff(m, struct mpls *, hoff); 94 95 label = MPLS_LABEL(ntohl(mpls->mpls_shim)); 96 ifp = m->m_pkthdr.rcvif; 97 m_sethash(m, MPLSP_MPORT_HASH(label, ifp->if_index)); 98 } 99