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!\n")); 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 } 102 103 /* 104 * Transform the Ethernet header into an Ethernet header 105 * with 802.1Q encapsulation. 106 */ 107 bcopy(mtod(m, char *) + EVL_ENCAPLEN, mtod(m, char *), 108 sizeof(struct ether_header)); 109 evl = mtod(m, struct ether_vlan_header *); 110 evl->evl_proto = evl->evl_encap_proto; 111 evl->evl_encap_proto = htons(ETHERTYPE_VLAN); 112 evl->evl_tag = htons(vlantag); 113 #ifdef DEBUG 114 kprintf("vlan_start: %*D\n", (int)sizeof *evl, 115 (unsigned char *)evl, ":"); 116 #endif 117 /* Hardware does not need to setup vlan tagging */ 118 m->m_flags &= ~M_VLANTAG; 119 } 120 ifq_handoff(ifp, m, &pktattr); 121 back: 122 ifnet_deserialize_tx(ifp); 123 } 124 125 void 126 vlan_ether_ptap(struct bpf_if *bp, struct mbuf *m, uint16_t vlantag) 127 { 128 const struct ether_header *eh; 129 struct ether_vlan_header evh; 130 131 KASSERT(m->m_len >= ETHER_HDR_LEN, 132 ("ether header is not contiguous!\n")); 133 134 eh = mtod(m, const struct ether_header *); 135 m_adj(m, ETHER_HDR_LEN); 136 137 bcopy(eh, &evh, 2 * ETHER_ADDR_LEN); 138 evh.evl_encap_proto = htons(ETHERTYPE_VLAN); 139 evh.evl_tag = htons(vlantag); 140 evh.evl_proto = eh->ether_type; 141 bpf_ptap(bp, m, &evh, ETHER_HDR_LEN + EVL_ENCAPLEN); 142 143 /* XXX assumes data was left intact */ 144 M_PREPEND(m, ETHER_HDR_LEN, MB_WAIT); 145 } 146 147 void 148 vlan_ether_decap(struct mbuf **m0) 149 { 150 struct mbuf *m = *m0; 151 struct ether_vlan_header *evh; 152 153 KKASSERT((m->m_flags & M_VLANTAG) == 0); 154 155 if (m->m_len < sizeof(*evh)) { 156 /* Error in the caller */ 157 m_freem(m); 158 *m0 = NULL; 159 return; 160 } 161 evh = mtod(m, struct ether_vlan_header *); 162 163 m->m_pkthdr.ether_vlantag = ntohs(evh->evl_tag); 164 m->m_flags |= M_VLANTAG; 165 166 bcopy((uint8_t *)evh, (uint8_t *)evh + EVL_ENCAPLEN, 167 2 * ETHER_ADDR_LEN); 168 m_adj(m, EVL_ENCAPLEN); 169 *m0 = m; 170 } 171