1 /* 2 * Copyright 1998 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 * $FreeBSD: src/sys/net/if_vlan.c,v 1.15.2.13 2003/02/14 22:25:58 fenner Exp $ 30 */ 31 32 #include <sys/param.h> 33 #include <sys/malloc.h> /* for M_NOWAIT */ 34 #include <sys/mbuf.h> 35 #include <sys/serialize.h> 36 37 #include <net/bpf.h> 38 #include <net/ethernet.h> 39 #include <net/if.h> 40 #include <net/if_arp.h> 41 #include <net/ifq_var.h> 42 #include <net/netmsg.h> 43 44 #include <net/vlan/if_vlan_var.h> 45 #include <net/vlan/if_vlan_ether.h> 46 47 void 48 vlan_start_dispatch(netmsg_t msg) 49 { 50 struct netmsg_packet *nmp = &msg->packet; 51 struct mbuf *m; 52 struct ifnet *ifp; 53 struct altq_pktattr pktattr; 54 #ifdef DEBUG 55 char hexstr[HEX_NCPYLEN(sizeof(struct ether_vlan_header))]; 56 #endif 57 m = nmp->nm_packet; 58 ifp = msg->lmsg.u.ms_resultp; 59 60 M_ASSERTPKTHDR(m); 61 KASSERT(m->m_flags & M_VLANTAG, ("mbuf has not been vlan tagged!")); 62 63 /* 64 * If ALTQ is enabled on the parent interface, do 65 * classification; the queueing discipline might 66 * not require classification, but might require 67 * the address family/header pointer in the pktattr. 68 */ 69 if (ifq_is_enabled(&ifp->if_snd)) 70 altq_etherclassify(&ifp->if_snd, m, &pktattr); 71 72 /* 73 * If underlying interface can do VLAN tag insertion itself, 74 * just pass the packet along. 75 */ 76 if ((ifp->if_capenable & IFCAP_VLAN_HWTAGGING) == 0) { 77 uint16_t vlantag = m->m_pkthdr.ether_vlantag; 78 struct ether_vlan_header *evl; 79 80 M_PREPEND(m, EVL_ENCAPLEN, M_NOWAIT); 81 if (m == NULL) { 82 if_printf(ifp, "vlan%u M_PREPEND failed", vlantag); 83 return; 84 } 85 /* M_PREPEND takes care of m_len, m_pkthdr.len for us */ 86 87 m = m_pullup(m, ETHER_HDR_LEN + EVL_ENCAPLEN); 88 if (m == NULL) { 89 if_printf(ifp, "vlan%u m_pullup failed", vlantag); 90 return; 91 } 92 m->m_pkthdr.csum_lhlen = sizeof(struct ether_vlan_header); 93 94 /* 95 * Transform the Ethernet header into an Ethernet header 96 * with 802.1Q encapsulation. 97 */ 98 bcopy(mtod(m, char *) + EVL_ENCAPLEN, mtod(m, char *), 99 sizeof(struct ether_header)); 100 evl = mtod(m, struct ether_vlan_header *); 101 evl->evl_proto = evl->evl_encap_proto; 102 evl->evl_encap_proto = htons(ETHERTYPE_VLAN); 103 evl->evl_tag = htons(vlantag); 104 #ifdef DEBUG 105 kprintf("vlan_start: %s\n", hexncpy((u_char *)evl, sizeof(*evl), 106 hexstr, HEX_NCPYLEN(sizeof(*evl)), ":")); 107 #endif 108 /* Hardware does not need to setup vlan tagging */ 109 m->m_flags &= ~M_VLANTAG; 110 } 111 ifq_dispatch(ifp, m, &pktattr); 112 } 113 114 void 115 vlan_ether_ptap(struct bpf_if *bp, struct mbuf *m, uint16_t vlantag) 116 { 117 const struct ether_header *eh; 118 struct ether_vlan_header evh; 119 120 KASSERT(m->m_len >= ETHER_HDR_LEN, 121 ("ether header is not contiguous!")); 122 123 eh = mtod(m, const struct ether_header *); 124 m_adj(m, ETHER_HDR_LEN); 125 126 bcopy(eh, &evh, 2 * ETHER_ADDR_LEN); 127 evh.evl_encap_proto = htons(ETHERTYPE_VLAN); 128 evh.evl_tag = htons(vlantag); 129 evh.evl_proto = eh->ether_type; 130 bpf_ptap(bp, m, &evh, ETHER_HDR_LEN + EVL_ENCAPLEN); 131 132 /* XXX assumes data was left intact */ 133 M_PREPEND(m, ETHER_HDR_LEN, M_WAITOK); 134 } 135 136 void 137 vlan_ether_decap(struct mbuf **m0) 138 { 139 struct mbuf *m = *m0; 140 struct ether_vlan_header *evh; 141 142 KKASSERT((m->m_flags & M_VLANTAG) == 0); 143 144 if (m->m_len < sizeof(*evh)) { 145 /* Error in the caller */ 146 m_freem(m); 147 *m0 = NULL; 148 return; 149 } 150 evh = mtod(m, struct ether_vlan_header *); 151 152 m->m_pkthdr.ether_vlantag = ntohs(evh->evl_tag); 153 m->m_flags |= M_VLANTAG; 154 155 bcopy((uint8_t *)evh, (uint8_t *)evh + EVL_ENCAPLEN, 156 2 * ETHER_ADDR_LEN); 157 m_adj(m, EVL_ENCAPLEN); 158 *m0 = m; 159 } 160