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/mbuf.h> 34 #include <sys/serialize.h> 35 36 #include <net/bpf.h> 37 #include <net/ethernet.h> 38 #include <net/if.h> 39 #include <net/if_arp.h> 40 #include <net/ifq_var.h> 41 #include <net/netmsg.h> 42 43 #include <net/vlan/if_vlan_var.h> 44 #include <net/vlan/if_vlan_ether.h> 45 46 void 47 vlan_start_dispatch(netmsg_t msg) 48 { 49 struct netmsg_packet *nmp = &msg->packet; 50 struct mbuf *m; 51 struct ifnet *ifp; 52 struct altq_pktattr pktattr; 53 54 m = nmp->nm_packet; 55 ifp = msg->lmsg.u.ms_resultp; 56 57 M_ASSERTPKTHDR(m); 58 KASSERT(m->m_flags & M_VLANTAG, ("mbuf has not been vlan tagged!")); 59 60 ifnet_serialize_tx(ifp); 61 62 /* 63 * Make sure that the interface is still UP and RUNNING, 64 * since interface state may have been changed when the 65 * mbuf is pending on the msgport. 66 */ 67 if ((ifp->if_flags & (IFF_UP | IFF_RUNNING)) != 68 (IFF_UP | IFF_RUNNING)) { 69 m_freem(m); 70 goto back; 71 } 72 73 /* 74 * If ALTQ is enabled on the parent interface, do 75 * classification; the queueing discipline might 76 * not require classification, but might require 77 * the address family/header pointer in the pktattr. 78 */ 79 if (ifq_is_enabled(&ifp->if_snd)) 80 altq_etherclassify(&ifp->if_snd, m, &pktattr); 81 82 /* 83 * If underlying interface can do VLAN tag insertion itself, 84 * just pass the packet along. 85 */ 86 if ((ifp->if_capenable & IFCAP_VLAN_HWTAGGING) == 0) { 87 uint16_t vlantag = m->m_pkthdr.ether_vlantag; 88 struct ether_vlan_header *evl; 89 90 M_PREPEND(m, EVL_ENCAPLEN, MB_DONTWAIT); 91 if (m == NULL) { 92 if_printf(ifp, "vlan%u M_PREPEND failed", vlantag); 93 goto back; 94 } 95 /* M_PREPEND takes care of m_len, m_pkthdr.len for us */ 96 97 m = m_pullup(m, ETHER_HDR_LEN + EVL_ENCAPLEN); 98 if (m == NULL) { 99 if_printf(ifp, "vlan%u m_pullup failed", vlantag); 100 goto back; 101 } 102 m->m_pkthdr.csum_lhlen = sizeof(struct ether_vlan_header); 103 104 /* 105 * Transform the Ethernet header into an Ethernet header 106 * with 802.1Q encapsulation. 107 */ 108 bcopy(mtod(m, char *) + EVL_ENCAPLEN, mtod(m, char *), 109 sizeof(struct ether_header)); 110 evl = mtod(m, struct ether_vlan_header *); 111 evl->evl_proto = evl->evl_encap_proto; 112 evl->evl_encap_proto = htons(ETHERTYPE_VLAN); 113 evl->evl_tag = htons(vlantag); 114 #ifdef DEBUG 115 kprintf("vlan_start: %*D\n", (int)sizeof *evl, 116 (unsigned char *)evl, ":"); 117 #endif 118 /* Hardware does not need to setup vlan tagging */ 119 m->m_flags &= ~M_VLANTAG; 120 } 121 ifq_handoff(ifp, m, &pktattr); 122 back: 123 ifnet_deserialize_tx(ifp); 124 } 125 126 void 127 vlan_ether_ptap(struct bpf_if *bp, struct mbuf *m, uint16_t vlantag) 128 { 129 const struct ether_header *eh; 130 struct ether_vlan_header evh; 131 132 KASSERT(m->m_len >= ETHER_HDR_LEN, 133 ("ether header is not contiguous!")); 134 135 eh = mtod(m, const struct ether_header *); 136 m_adj(m, ETHER_HDR_LEN); 137 138 bcopy(eh, &evh, 2 * ETHER_ADDR_LEN); 139 evh.evl_encap_proto = htons(ETHERTYPE_VLAN); 140 evh.evl_tag = htons(vlantag); 141 evh.evl_proto = eh->ether_type; 142 bpf_ptap(bp, m, &evh, ETHER_HDR_LEN + EVL_ENCAPLEN); 143 144 /* XXX assumes data was left intact */ 145 M_PREPEND(m, ETHER_HDR_LEN, MB_WAIT); 146 } 147 148 void 149 vlan_ether_decap(struct mbuf **m0) 150 { 151 struct mbuf *m = *m0; 152 struct ether_vlan_header *evh; 153 154 KKASSERT((m->m_flags & M_VLANTAG) == 0); 155 156 if (m->m_len < sizeof(*evh)) { 157 /* Error in the caller */ 158 m_freem(m); 159 *m0 = NULL; 160 return; 161 } 162 evh = mtod(m, struct ether_vlan_header *); 163 164 m->m_pkthdr.ether_vlantag = ntohs(evh->evl_tag); 165 m->m_flags |= M_VLANTAG; 166 167 bcopy((uint8_t *)evh, (uint8_t *)evh + EVL_ENCAPLEN, 168 2 * ETHER_ADDR_LEN); 169 m_adj(m, EVL_ENCAPLEN); 170 *m0 = m; 171 } 172