1 #include <linux/skbuff.h> 2 #include <linux/netdevice.h> 3 #include <linux/if_vlan.h> 4 #include <linux/netpoll.h> 5 #include "vlan.h" 6 7 bool vlan_do_receive(struct sk_buff **skbp) 8 { 9 struct sk_buff *skb = *skbp; 10 u16 vlan_id = skb->vlan_tci & VLAN_VID_MASK; 11 struct net_device *vlan_dev; 12 struct vlan_pcpu_stats *rx_stats; 13 14 vlan_dev = vlan_find_dev(skb->dev, vlan_id); 15 if (!vlan_dev) { 16 if (vlan_id) 17 skb->pkt_type = PACKET_OTHERHOST; 18 return false; 19 } 20 21 skb = *skbp = skb_share_check(skb, GFP_ATOMIC); 22 if (unlikely(!skb)) 23 return false; 24 25 skb->dev = vlan_dev; 26 skb->priority = vlan_get_ingress_priority(vlan_dev, skb->vlan_tci); 27 skb->vlan_tci = 0; 28 29 rx_stats = this_cpu_ptr(vlan_dev_info(vlan_dev)->vlan_pcpu_stats); 30 31 u64_stats_update_begin(&rx_stats->syncp); 32 rx_stats->rx_packets++; 33 rx_stats->rx_bytes += skb->len; 34 35 switch (skb->pkt_type) { 36 case PACKET_BROADCAST: 37 break; 38 case PACKET_MULTICAST: 39 rx_stats->rx_multicast++; 40 break; 41 case PACKET_OTHERHOST: 42 /* Our lower layer thinks this is not local, let's make sure. 43 * This allows the VLAN to have a different MAC than the 44 * underlying device, and still route correctly. */ 45 if (!compare_ether_addr(eth_hdr(skb)->h_dest, 46 vlan_dev->dev_addr)) 47 skb->pkt_type = PACKET_HOST; 48 break; 49 } 50 u64_stats_update_end(&rx_stats->syncp); 51 52 return true; 53 } 54 55 struct net_device *vlan_dev_real_dev(const struct net_device *dev) 56 { 57 return vlan_dev_info(dev)->real_dev; 58 } 59 EXPORT_SYMBOL(vlan_dev_real_dev); 60 61 u16 vlan_dev_vlan_id(const struct net_device *dev) 62 { 63 return vlan_dev_info(dev)->vlan_id; 64 } 65 EXPORT_SYMBOL(vlan_dev_vlan_id); 66 67 /* VLAN rx hw acceleration helper. This acts like netif_{rx,receive_skb}(). */ 68 int __vlan_hwaccel_rx(struct sk_buff *skb, struct vlan_group *grp, 69 u16 vlan_tci, int polling) 70 { 71 __vlan_hwaccel_put_tag(skb, vlan_tci); 72 return polling ? netif_receive_skb(skb) : netif_rx(skb); 73 } 74 EXPORT_SYMBOL(__vlan_hwaccel_rx); 75 76 gro_result_t vlan_gro_receive(struct napi_struct *napi, struct vlan_group *grp, 77 unsigned int vlan_tci, struct sk_buff *skb) 78 { 79 __vlan_hwaccel_put_tag(skb, vlan_tci); 80 return napi_gro_receive(napi, skb); 81 } 82 EXPORT_SYMBOL(vlan_gro_receive); 83 84 gro_result_t vlan_gro_frags(struct napi_struct *napi, struct vlan_group *grp, 85 unsigned int vlan_tci) 86 { 87 __vlan_hwaccel_put_tag(napi->skb, vlan_tci); 88 return napi_gro_frags(napi); 89 } 90 EXPORT_SYMBOL(vlan_gro_frags); 91 92 static struct sk_buff *vlan_check_reorder_header(struct sk_buff *skb) 93 { 94 if (vlan_dev_info(skb->dev)->flags & VLAN_FLAG_REORDER_HDR) { 95 if (skb_cow(skb, skb_headroom(skb)) < 0) 96 skb = NULL; 97 if (skb) { 98 /* Lifted from Gleb's VLAN code... */ 99 memmove(skb->data - ETH_HLEN, 100 skb->data - VLAN_ETH_HLEN, 12); 101 skb->mac_header += VLAN_HLEN; 102 } 103 } 104 return skb; 105 } 106 107 static void vlan_set_encap_proto(struct sk_buff *skb, struct vlan_hdr *vhdr) 108 { 109 __be16 proto; 110 unsigned char *rawp; 111 112 /* 113 * Was a VLAN packet, grab the encapsulated protocol, which the layer 114 * three protocols care about. 115 */ 116 117 proto = vhdr->h_vlan_encapsulated_proto; 118 if (ntohs(proto) >= 1536) { 119 skb->protocol = proto; 120 return; 121 } 122 123 rawp = skb->data; 124 if (*(unsigned short *) rawp == 0xFFFF) 125 /* 126 * This is a magic hack to spot IPX packets. Older Novell 127 * breaks the protocol design and runs IPX over 802.3 without 128 * an 802.2 LLC layer. We look for FFFF which isn't a used 129 * 802.2 SSAP/DSAP. This won't work for fault tolerant netware 130 * but does for the rest. 131 */ 132 skb->protocol = htons(ETH_P_802_3); 133 else 134 /* 135 * Real 802.2 LLC 136 */ 137 skb->protocol = htons(ETH_P_802_2); 138 } 139 140 struct sk_buff *vlan_untag(struct sk_buff *skb) 141 { 142 struct vlan_hdr *vhdr; 143 u16 vlan_tci; 144 145 if (unlikely(vlan_tx_tag_present(skb))) { 146 /* vlan_tci is already set-up so leave this for another time */ 147 return skb; 148 } 149 150 skb = skb_share_check(skb, GFP_ATOMIC); 151 if (unlikely(!skb)) 152 goto err_free; 153 154 if (unlikely(!pskb_may_pull(skb, VLAN_HLEN))) 155 goto err_free; 156 157 vhdr = (struct vlan_hdr *) skb->data; 158 vlan_tci = ntohs(vhdr->h_vlan_TCI); 159 __vlan_hwaccel_put_tag(skb, vlan_tci); 160 161 skb_pull_rcsum(skb, VLAN_HLEN); 162 vlan_set_encap_proto(skb, vhdr); 163 164 skb = vlan_check_reorder_header(skb); 165 if (unlikely(!skb)) 166 goto err_free; 167 168 return skb; 169 170 err_free: 171 kfree_skb(skb); 172 return NULL; 173 } 174