/* -*- linux-c -*- * INET 802.1Q VLAN * Ethernet-type device handling. * * Authors: Ben Greear * Please send support related email to: vlan@scry.wanfear.com * VLAN Home Page: http://www.candelatech.com/~greear/vlan.html * * Fixes: Mar 22 2001: Martin Bokaemper * - reset skb->pkt_type on incoming packets when MAC was changed * - see that changed MAC is saddr for outgoing packets * Oct 20, 2001: Ard van Breeman: * - Fix MC-list, finally. * - Flush MC-list on VLAN destroy. * * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. */ #include #include #include #include #include /* for copy_from_user */ #include #include #include #include #include #include #include "vlan.h" #include "vlanproc.h" #include #include /* * Rebuild the Ethernet MAC header. This is called after an ARP * (or in future other address resolution) has completed on this * sk_buff. We now let ARP fill in the other fields. * * This routine CANNOT use cached dst->neigh! * Really, it is used only when dst->neigh is wrong. * * TODO: This needs a checkup, I'm ignorant here. --BLG */ static int vlan_dev_rebuild_header(struct sk_buff *skb) { struct net_device *dev = skb->dev; struct vlan_ethhdr *veth = (struct vlan_ethhdr *)(skb->data); switch (veth->h_vlan_encapsulated_proto) { #ifdef CONFIG_INET case __constant_htons(ETH_P_IP): /* TODO: Confirm this will work with VLAN headers... */ return arp_find(veth->h_dest, skb); #endif default: printk(VLAN_DBG "%s: unable to resolve type %X addresses.\n", dev->name, ntohs(veth->h_vlan_encapsulated_proto)); memcpy(veth->h_source, dev->dev_addr, ETH_ALEN); break; } return 0; } static inline struct sk_buff *vlan_check_reorder_header(struct sk_buff *skb) { if (VLAN_DEV_INFO(skb->dev)->flags & VLAN_FLAG_REORDER_HDR) { if (skb_shared(skb) || skb_cloned(skb)) { struct sk_buff *nskb = skb_copy(skb, GFP_ATOMIC); kfree_skb(skb); skb = nskb; } if (skb) { /* Lifted from Gleb's VLAN code... */ memmove(skb->data - ETH_HLEN, skb->data - VLAN_ETH_HLEN, 12); skb->mac_header += VLAN_HLEN; } } return skb; } /* * Determine the packet's protocol ID. The rule here is that we * assume 802.3 if the type field is short enough to be a length. * This is normal practice and works for any 'now in use' protocol. * * Also, at this point we assume that we ARE dealing exclusively with * VLAN packets, or packets that should be made into VLAN packets based * on a default VLAN ID. * * NOTE: Should be similar to ethernet/eth.c. * * SANITY NOTE: This method is called when a packet is moving up the stack * towards userland. To get here, it would have already passed * through the ethernet/eth.c eth_type_trans() method. * SANITY NOTE 2: We are referencing to the VLAN_HDR frields, which MAY be * stored UNALIGNED in the memory. RISC systems don't like * such cases very much... * SANITY NOTE 2a: According to Dave Miller & Alexey, it will always be aligned, * so there doesn't need to be any of the unaligned stuff. It has * been commented out now... --Ben * */ int vlan_skb_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type* ptype, struct net_device *orig_dev) { unsigned char *rawp = NULL; struct vlan_hdr *vhdr; unsigned short vid; struct net_device_stats *stats; unsigned short vlan_TCI; __be16 proto; if (dev->nd_net != &init_net) { kfree_skb(skb); return -1; } if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL) return -1; if (unlikely(!pskb_may_pull(skb, VLAN_HLEN))) { kfree_skb(skb); return -1; } vhdr = (struct vlan_hdr *)(skb->data); /* vlan_TCI = ntohs(get_unaligned(&vhdr->h_vlan_TCI)); */ vlan_TCI = ntohs(vhdr->h_vlan_TCI); vid = (vlan_TCI & VLAN_VID_MASK); #ifdef VLAN_DEBUG printk(VLAN_DBG "%s: skb: %p vlan_id: %hx\n", __FUNCTION__, skb, vid); #endif /* Ok, we will find the correct VLAN device, strip the header, * and then go on as usual. */ /* We have 12 bits of vlan ID. * * We must not drop allow preempt until we hold a * reference to the device (netif_rx does that) or we * fail. */ rcu_read_lock(); skb->dev = __find_vlan_dev(dev, vid); if (!skb->dev) { rcu_read_unlock(); #ifdef VLAN_DEBUG printk(VLAN_DBG "%s: ERROR: No net_device for VID: %i on dev: %s [%i]\n", __FUNCTION__, (unsigned int)(vid), dev->name, dev->ifindex); #endif kfree_skb(skb); return -1; } skb->dev->last_rx = jiffies; /* Bump the rx counters for the VLAN device. */ stats = &skb->dev->stats; stats->rx_packets++; stats->rx_bytes += skb->len; /* Take off the VLAN header (4 bytes currently) */ skb_pull_rcsum(skb, VLAN_HLEN); /* * Deal with ingress priority mapping. */ skb->priority = vlan_get_ingress_priority(skb->dev, ntohs(vhdr->h_vlan_TCI)); #ifdef VLAN_DEBUG printk(VLAN_DBG "%s: priority: %lu for TCI: %hu (hbo)\n", __FUNCTION__, (unsigned long)(skb->priority), ntohs(vhdr->h_vlan_TCI)); #endif /* The ethernet driver already did the pkt_type calculations * for us... */ switch (skb->pkt_type) { case PACKET_BROADCAST: /* Yeah, stats collect these together.. */ // stats->broadcast ++; // no such counter :-( break; case PACKET_MULTICAST: stats->multicast++; break; case PACKET_OTHERHOST: /* Our lower layer thinks this is not local, let's make sure. * This allows the VLAN to have a different MAC than the underlying * device, and still route correctly. */ if (!compare_ether_addr(eth_hdr(skb)->h_dest, skb->dev->dev_addr)) { /* It is for our (changed) MAC-address! */ skb->pkt_type = PACKET_HOST; } break; default: break; } /* Was a VLAN packet, grab the encapsulated protocol, which the layer * three protocols care about. */ /* proto = get_unaligned(&vhdr->h_vlan_encapsulated_proto); */ proto = vhdr->h_vlan_encapsulated_proto; skb->protocol = proto; if (ntohs(proto) >= 1536) { /* place it back on the queue to be handled by * true layer 3 protocols. */ /* See if we are configured to re-write the VLAN header * to make it look like ethernet... */ skb = vlan_check_reorder_header(skb); /* Can be null if skb-clone fails when re-ordering */ if (skb) { netif_rx(skb); } else { /* TODO: Add a more specific counter here. */ stats->rx_errors++; } rcu_read_unlock(); return 0; } rawp = skb->data; /* * This is a magic hack to spot IPX packets. Older Novell breaks * the protocol design and runs IPX over 802.3 without an 802.2 LLC * layer. We look for FFFF which isn't a used 802.2 SSAP/DSAP. This * won't work for fault tolerant netware but does for the rest. */ if (*(unsigned short *)rawp == 0xFFFF) { skb->protocol = htons(ETH_P_802_3); /* place it back on the queue to be handled by true layer 3 protocols. */ /* See if we are configured to re-write the VLAN header * to make it look like ethernet... */ skb = vlan_check_reorder_header(skb); /* Can be null if skb-clone fails when re-ordering */ if (skb) { netif_rx(skb); } else { /* TODO: Add a more specific counter here. */ stats->rx_errors++; } rcu_read_unlock(); return 0; } /* * Real 802.2 LLC */ skb->protocol = htons(ETH_P_802_2); /* place it back on the queue to be handled by upper layer protocols. */ /* See if we are configured to re-write the VLAN header * to make it look like ethernet... */ skb = vlan_check_reorder_header(skb); /* Can be null if skb-clone fails when re-ordering */ if (skb) { netif_rx(skb); } else { /* TODO: Add a more specific counter here. */ stats->rx_errors++; } rcu_read_unlock(); return 0; } static inline unsigned short vlan_dev_get_egress_qos_mask(struct net_device* dev, struct sk_buff* skb) { struct vlan_priority_tci_mapping *mp = VLAN_DEV_INFO(dev)->egress_priority_map[(skb->priority & 0xF)]; while (mp) { if (mp->priority == skb->priority) { return mp->vlan_qos; /* This should already be shifted to mask * correctly with the VLAN's TCI */ } mp = mp->next; } return 0; } /* * Create the VLAN header for an arbitrary protocol layer * * saddr=NULL means use device source address * daddr=NULL means leave destination address (eg unresolved arp) * * This is called when the SKB is moving down the stack towards the * physical devices. */ static int vlan_dev_hard_header(struct sk_buff *skb, struct net_device *dev, unsigned short type, const void *daddr, const void *saddr, unsigned int len) { struct vlan_hdr *vhdr; unsigned short veth_TCI = 0; int rc = 0; int build_vlan_header = 0; struct net_device *vdev = dev; /* save this for the bottom of the method */ #ifdef VLAN_DEBUG printk(VLAN_DBG "%s: skb: %p type: %hx len: %x vlan_id: %hx, daddr: %p\n", __FUNCTION__, skb, type, len, VLAN_DEV_INFO(dev)->vlan_id, daddr); #endif /* build vlan header only if re_order_header flag is NOT set. This * fixes some programs that get confused when they see a VLAN device * sending a frame that is VLAN encoded (the consensus is that the VLAN * device should look completely like an Ethernet device when the * REORDER_HEADER flag is set) The drawback to this is some extra * header shuffling in the hard_start_xmit. Users can turn off this * REORDER behaviour with the vconfig tool. */ if (!(VLAN_DEV_INFO(dev)->flags & VLAN_FLAG_REORDER_HDR)) build_vlan_header = 1; if (build_vlan_header) { vhdr = (struct vlan_hdr *) skb_push(skb, VLAN_HLEN); /* build the four bytes that make this a VLAN header. */ /* Now, construct the second two bytes. This field looks something * like: * usr_priority: 3 bits (high bits) * CFI 1 bit * VLAN ID 12 bits (low bits) * */ veth_TCI = VLAN_DEV_INFO(dev)->vlan_id; veth_TCI |= vlan_dev_get_egress_qos_mask(dev, skb); vhdr->h_vlan_TCI = htons(veth_TCI); /* * Set the protocol type. * For a packet of type ETH_P_802_3 we put the length in here instead. * It is up to the 802.2 layer to carry protocol information. */ if (type != ETH_P_802_3) { vhdr->h_vlan_encapsulated_proto = htons(type); } else { vhdr->h_vlan_encapsulated_proto = htons(len); } skb->protocol = htons(ETH_P_8021Q); skb_reset_network_header(skb); } /* Before delegating work to the lower layer, enter our MAC-address */ if (saddr == NULL) saddr = dev->dev_addr; dev = VLAN_DEV_INFO(dev)->real_dev; /* MPLS can send us skbuffs w/out enough space. This check will grow the * skb if it doesn't have enough headroom. Not a beautiful solution, so * I'll tick a counter so that users can know it's happening... If they * care... */ /* NOTE: This may still break if the underlying device is not the final * device (and thus there are more headers to add...) It should work for * good-ole-ethernet though. */ if (skb_headroom(skb) < dev->hard_header_len) { struct sk_buff *sk_tmp = skb; skb = skb_realloc_headroom(sk_tmp, dev->hard_header_len); kfree_skb(sk_tmp); if (skb == NULL) { struct net_device_stats *stats = &vdev->stats; stats->tx_dropped++; return -ENOMEM; } VLAN_DEV_INFO(vdev)->cnt_inc_headroom_on_tx++; #ifdef VLAN_DEBUG printk(VLAN_DBG "%s: %s: had to grow skb.\n", __FUNCTION__, vdev->name); #endif } if (build_vlan_header) { /* Now make the underlying real hard header */ rc = dev_hard_header(skb, dev, ETH_P_8021Q, daddr, saddr, len + VLAN_HLEN); if (rc > 0) rc += VLAN_HLEN; else if (rc < 0) rc -= VLAN_HLEN; } else /* If here, then we'll just make a normal looking ethernet frame, * but, the hard_start_xmit method will insert the tag (it has to * be able to do this for bridged and other skbs that don't come * down the protocol stack in an orderly manner. */ rc = dev_hard_header(skb, dev, type, daddr, saddr, len); return rc; } static int vlan_dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev) { struct net_device_stats *stats = &dev->stats; struct vlan_ethhdr *veth = (struct vlan_ethhdr *)(skb->data); /* Handle non-VLAN frames if they are sent to us, for example by DHCP. * * NOTE: THIS ASSUMES DIX ETHERNET, SPECIFICALLY NOT SUPPORTING * OTHER THINGS LIKE FDDI/TokenRing/802.3 SNAPs... */ if (veth->h_vlan_proto != htons(ETH_P_8021Q) || VLAN_DEV_INFO(dev)->flags & VLAN_FLAG_REORDER_HDR) { int orig_headroom = skb_headroom(skb); unsigned short veth_TCI; /* This is not a VLAN frame...but we can fix that! */ VLAN_DEV_INFO(dev)->cnt_encap_on_xmit++; #ifdef VLAN_DEBUG printk(VLAN_DBG "%s: proto to encap: 0x%hx (hbo)\n", __FUNCTION__, htons(veth->h_vlan_proto)); #endif /* Construct the second two bytes. This field looks something * like: * usr_priority: 3 bits (high bits) * CFI 1 bit * VLAN ID 12 bits (low bits) */ veth_TCI = VLAN_DEV_INFO(dev)->vlan_id; veth_TCI |= vlan_dev_get_egress_qos_mask(dev, skb); skb = __vlan_put_tag(skb, veth_TCI); if (!skb) { stats->tx_dropped++; return 0; } if (orig_headroom < VLAN_HLEN) { VLAN_DEV_INFO(dev)->cnt_inc_headroom_on_tx++; } } #ifdef VLAN_DEBUG printk(VLAN_DBG "%s: about to send skb: %p to dev: %s\n", __FUNCTION__, skb, skb->dev->name); printk(VLAN_DBG " %2hx.%2hx.%2hx.%2xh.%2hx.%2hx %2hx.%2hx.%2hx.%2hx.%2hx.%2hx %4hx %4hx %4hx\n", veth->h_dest[0], veth->h_dest[1], veth->h_dest[2], veth->h_dest[3], veth->h_dest[4], veth->h_dest[5], veth->h_source[0], veth->h_source[1], veth->h_source[2], veth->h_source[3], veth->h_source[4], veth->h_source[5], veth->h_vlan_proto, veth->h_vlan_TCI, veth->h_vlan_encapsulated_proto); #endif stats->tx_packets++; /* for statics only */ stats->tx_bytes += skb->len; skb->dev = VLAN_DEV_INFO(dev)->real_dev; dev_queue_xmit(skb); return 0; } static int vlan_dev_hwaccel_hard_start_xmit(struct sk_buff *skb, struct net_device *dev) { struct net_device_stats *stats = &dev->stats; unsigned short veth_TCI; /* Construct the second two bytes. This field looks something * like: * usr_priority: 3 bits (high bits) * CFI 1 bit * VLAN ID 12 bits (low bits) */ veth_TCI = VLAN_DEV_INFO(dev)->vlan_id; veth_TCI |= vlan_dev_get_egress_qos_mask(dev, skb); skb = __vlan_hwaccel_put_tag(skb, veth_TCI); stats->tx_packets++; stats->tx_bytes += skb->len; skb->dev = VLAN_DEV_INFO(dev)->real_dev; dev_queue_xmit(skb); return 0; } static int vlan_dev_change_mtu(struct net_device *dev, int new_mtu) { /* TODO: gotta make sure the underlying layer can handle it, * maybe an IFF_VLAN_CAPABLE flag for devices? */ if (VLAN_DEV_INFO(dev)->real_dev->mtu < new_mtu) return -ERANGE; dev->mtu = new_mtu; return 0; } void vlan_dev_set_ingress_priority(const struct net_device *dev, u32 skb_prio, short vlan_prio) { struct vlan_dev_info *vlan = VLAN_DEV_INFO(dev); if (vlan->ingress_priority_map[vlan_prio & 0x7] && !skb_prio) vlan->nr_ingress_mappings--; else if (!vlan->ingress_priority_map[vlan_prio & 0x7] && skb_prio) vlan->nr_ingress_mappings++; vlan->ingress_priority_map[vlan_prio & 0x7] = skb_prio; } int vlan_dev_set_egress_priority(const struct net_device *dev, u32 skb_prio, short vlan_prio) { struct vlan_dev_info *vlan = VLAN_DEV_INFO(dev); struct vlan_priority_tci_mapping *mp = NULL; struct vlan_priority_tci_mapping *np; u32 vlan_qos = (vlan_prio << 13) & 0xE000; /* See if a priority mapping exists.. */ mp = vlan->egress_priority_map[skb_prio & 0xF]; while (mp) { if (mp->priority == skb_prio) { if (mp->vlan_qos && !vlan_qos) vlan->nr_egress_mappings--; else if (!mp->vlan_qos && vlan_qos) vlan->nr_egress_mappings++; mp->vlan_qos = vlan_qos; return 0; } mp = mp->next; } /* Create a new mapping then. */ mp = vlan->egress_priority_map[skb_prio & 0xF]; np = kmalloc(sizeof(struct vlan_priority_tci_mapping), GFP_KERNEL); if (!np) return -ENOBUFS; np->next = mp; np->priority = skb_prio; np->vlan_qos = vlan_qos; vlan->egress_priority_map[skb_prio & 0xF] = np; if (vlan_qos) vlan->nr_egress_mappings++; return 0; } /* Flags are defined in the vlan_flags enum in include/linux/if_vlan.h file. */ int vlan_dev_set_vlan_flag(const struct net_device *dev, u32 flag, short flag_val) { /* verify flag is supported */ if (flag == VLAN_FLAG_REORDER_HDR) { if (flag_val) { VLAN_DEV_INFO(dev)->flags |= VLAN_FLAG_REORDER_HDR; } else { VLAN_DEV_INFO(dev)->flags &= ~VLAN_FLAG_REORDER_HDR; } return 0; } printk(KERN_ERR "%s: flag %i is not valid.\n", __FUNCTION__, flag); return -EINVAL; } void vlan_dev_get_realdev_name(const struct net_device *dev, char *result) { strncpy(result, VLAN_DEV_INFO(dev)->real_dev->name, 23); } void vlan_dev_get_vid(const struct net_device *dev, unsigned short *result) { *result = VLAN_DEV_INFO(dev)->vlan_id; } static int vlan_dev_open(struct net_device *dev) { struct vlan_dev_info *vlan = VLAN_DEV_INFO(dev); struct net_device *real_dev = vlan->real_dev; int err; if (!(real_dev->flags & IFF_UP)) return -ENETDOWN; if (compare_ether_addr(dev->dev_addr, real_dev->dev_addr)) { err = dev_unicast_add(real_dev, dev->dev_addr, ETH_ALEN); if (err < 0) return err; } memcpy(vlan->real_dev_addr, real_dev->dev_addr, ETH_ALEN); if (dev->flags & IFF_ALLMULTI) dev_set_allmulti(real_dev, 1); if (dev->flags & IFF_PROMISC) dev_set_promiscuity(real_dev, 1); return 0; } static int vlan_dev_stop(struct net_device *dev) { struct net_device *real_dev = VLAN_DEV_INFO(dev)->real_dev; dev_mc_unsync(real_dev, dev); if (dev->flags & IFF_ALLMULTI) dev_set_allmulti(real_dev, -1); if (dev->flags & IFF_PROMISC) dev_set_promiscuity(real_dev, -1); if (compare_ether_addr(dev->dev_addr, real_dev->dev_addr)) dev_unicast_delete(real_dev, dev->dev_addr, dev->addr_len); return 0; } static int vlan_dev_set_mac_address(struct net_device *dev, void *p) { struct net_device *real_dev = VLAN_DEV_INFO(dev)->real_dev; struct sockaddr *addr = p; int err; if (!is_valid_ether_addr(addr->sa_data)) return -EADDRNOTAVAIL; if (!(dev->flags & IFF_UP)) goto out; if (compare_ether_addr(addr->sa_data, real_dev->dev_addr)) { err = dev_unicast_add(real_dev, addr->sa_data, ETH_ALEN); if (err < 0) return err; } if (compare_ether_addr(dev->dev_addr, real_dev->dev_addr)) dev_unicast_delete(real_dev, dev->dev_addr, ETH_ALEN); out: memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN); return 0; } static int vlan_dev_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) { struct net_device *real_dev = VLAN_DEV_INFO(dev)->real_dev; struct ifreq ifrr; int err = -EOPNOTSUPP; strncpy(ifrr.ifr_name, real_dev->name, IFNAMSIZ); ifrr.ifr_ifru = ifr->ifr_ifru; switch(cmd) { case SIOCGMIIPHY: case SIOCGMIIREG: case SIOCSMIIREG: if (real_dev->do_ioctl && netif_device_present(real_dev)) err = real_dev->do_ioctl(real_dev, &ifrr, cmd); break; } if (!err) ifr->ifr_ifru = ifrr.ifr_ifru; return err; } static void vlan_dev_change_rx_flags(struct net_device *dev, int change) { struct net_device *real_dev = VLAN_DEV_INFO(dev)->real_dev; if (change & IFF_ALLMULTI) dev_set_allmulti(real_dev, dev->flags & IFF_ALLMULTI ? 1 : -1); if (change & IFF_PROMISC) dev_set_promiscuity(real_dev, dev->flags & IFF_PROMISC ? 1 : -1); } static void vlan_dev_set_multicast_list(struct net_device *vlan_dev) { dev_mc_sync(VLAN_DEV_INFO(vlan_dev)->real_dev, vlan_dev); } /* * vlan network devices have devices nesting below it, and are a special * "super class" of normal network devices; split their locks off into a * separate class since they always nest. */ static struct lock_class_key vlan_netdev_xmit_lock_key; static const struct header_ops vlan_header_ops = { .create = vlan_dev_hard_header, .rebuild = vlan_dev_rebuild_header, .parse = eth_header_parse, }; static int vlan_dev_init(struct net_device *dev) { struct net_device *real_dev = VLAN_DEV_INFO(dev)->real_dev; int subclass = 0; /* IFF_BROADCAST|IFF_MULTICAST; ??? */ dev->flags = real_dev->flags & ~IFF_UP; dev->iflink = real_dev->ifindex; dev->state = (real_dev->state & ((1<<__LINK_STATE_NOCARRIER) | (1<<__LINK_STATE_DORMANT))) | (1<<__LINK_STATE_PRESENT); /* ipv6 shared card related stuff */ dev->dev_id = real_dev->dev_id; if (is_zero_ether_addr(dev->dev_addr)) memcpy(dev->dev_addr, real_dev->dev_addr, dev->addr_len); if (is_zero_ether_addr(dev->broadcast)) memcpy(dev->broadcast, real_dev->broadcast, dev->addr_len); if (real_dev->features & NETIF_F_HW_VLAN_TX) { dev->header_ops = real_dev->header_ops; dev->hard_header_len = real_dev->hard_header_len; dev->hard_start_xmit = vlan_dev_hwaccel_hard_start_xmit; } else { dev->header_ops = &vlan_header_ops; dev->hard_header_len = real_dev->hard_header_len + VLAN_HLEN; dev->hard_start_xmit = vlan_dev_hard_start_xmit; } if (real_dev->priv_flags & IFF_802_1Q_VLAN) subclass = 1; lockdep_set_class_and_subclass(&dev->_xmit_lock, &vlan_netdev_xmit_lock_key, subclass); return 0; } void vlan_setup(struct net_device *dev) { ether_setup(dev); dev->priv_flags |= IFF_802_1Q_VLAN; dev->tx_queue_len = 0; dev->change_mtu = vlan_dev_change_mtu; dev->init = vlan_dev_init; dev->open = vlan_dev_open; dev->stop = vlan_dev_stop; dev->set_mac_address = vlan_dev_set_mac_address; dev->set_multicast_list = vlan_dev_set_multicast_list; dev->change_rx_flags = vlan_dev_change_rx_flags; dev->do_ioctl = vlan_dev_ioctl; dev->destructor = free_netdev; memset(dev->broadcast, 0, ETH_ALEN); }