| /* |
| * VLAN An implementation of 802.1Q VLAN tagging. |
| * |
| * Authors: Ben Greear <greearb@candelatech.com> |
| * |
| * 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. |
| * |
| */ |
| #ifndef _LINUX_IF_VLAN_H_ |
| #define _LINUX_IF_VLAN_H_ |
| |
| #include <linux/netdevice.h> |
| #include <linux/etherdevice.h> |
| #include <linux/rtnetlink.h> |
| #include <linux/bug.h> |
| #include <uapi/linux/if_vlan.h> |
| |
| #define VLAN_HLEN 4 /* The additional bytes required by VLAN |
| * (in addition to the Ethernet header) |
| */ |
| #define VLAN_ETH_HLEN 18 /* Total octets in header. */ |
| #define VLAN_ETH_ZLEN 64 /* Min. octets in frame sans FCS */ |
| |
| /* |
| * According to 802.3ac, the packet can be 4 bytes longer. --Klika Jan |
| */ |
| #define VLAN_ETH_DATA_LEN 1500 /* Max. octets in payload */ |
| #define VLAN_ETH_FRAME_LEN 1518 /* Max. octets in frame sans FCS */ |
| |
| /* |
| * struct vlan_hdr - vlan header |
| * @h_vlan_TCI: priority and VLAN ID |
| * @h_vlan_encapsulated_proto: packet type ID or len |
| */ |
| struct vlan_hdr { |
| __be16 h_vlan_TCI; |
| __be16 h_vlan_encapsulated_proto; |
| }; |
| |
| /** |
| * struct vlan_ethhdr - vlan ethernet header (ethhdr + vlan_hdr) |
| * @h_dest: destination ethernet address |
| * @h_source: source ethernet address |
| * @h_vlan_proto: ethernet protocol (always 0x8100) |
| * @h_vlan_TCI: priority and VLAN ID |
| * @h_vlan_encapsulated_proto: packet type ID or len |
| */ |
| struct vlan_ethhdr { |
| unsigned char h_dest[ETH_ALEN]; |
| unsigned char h_source[ETH_ALEN]; |
| __be16 h_vlan_proto; |
| __be16 h_vlan_TCI; |
| __be16 h_vlan_encapsulated_proto; |
| }; |
| |
| #include <linux/skbuff.h> |
| |
| static inline struct vlan_ethhdr *vlan_eth_hdr(const struct sk_buff *skb) |
| { |
| return (struct vlan_ethhdr *)skb_mac_header(skb); |
| } |
| |
| #define VLAN_PRIO_MASK 0xe000 /* Priority Code Point */ |
| #define VLAN_PRIO_SHIFT 13 |
| #define VLAN_CFI_MASK 0x1000 /* Canonical Format Indicator */ |
| #define VLAN_TAG_PRESENT VLAN_CFI_MASK |
| #define VLAN_VID_MASK 0x0fff /* VLAN Identifier */ |
| #define VLAN_N_VID 4096 |
| |
| /* found in socket.c */ |
| extern void vlan_ioctl_set(int (*hook)(struct net *, void __user *)); |
| |
| static inline int is_vlan_dev(struct net_device *dev) |
| { |
| return dev->priv_flags & IFF_802_1Q_VLAN; |
| } |
| |
| #define vlan_tx_tag_present(__skb) ((__skb)->vlan_tci & VLAN_TAG_PRESENT) |
| #define vlan_tx_nonzero_tag_present(__skb) \ |
| (vlan_tx_tag_present(__skb) && ((__skb)->vlan_tci & VLAN_VID_MASK)) |
| #define vlan_tx_tag_get(__skb) ((__skb)->vlan_tci & ~VLAN_TAG_PRESENT) |
| |
| #if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE) |
| |
| extern struct net_device *__vlan_find_dev_deep(struct net_device *real_dev, |
| __be16 vlan_proto, u16 vlan_id); |
| extern struct net_device *vlan_dev_real_dev(const struct net_device *dev); |
| extern u16 vlan_dev_vlan_id(const struct net_device *dev); |
| |
| extern bool vlan_do_receive(struct sk_buff **skb); |
| extern struct sk_buff *vlan_untag(struct sk_buff *skb); |
| |
| extern int vlan_vid_add(struct net_device *dev, __be16 proto, u16 vid); |
| extern void vlan_vid_del(struct net_device *dev, __be16 proto, u16 vid); |
| |
| extern int vlan_vids_add_by_dev(struct net_device *dev, |
| const struct net_device *by_dev); |
| extern void vlan_vids_del_by_dev(struct net_device *dev, |
| const struct net_device *by_dev); |
| |
| extern bool vlan_uses_dev(const struct net_device *dev); |
| #else |
| static inline struct net_device * |
| __vlan_find_dev_deep(struct net_device *real_dev, u16 vlan_id) |
| { |
| return NULL; |
| } |
| |
| static inline struct net_device *vlan_dev_real_dev(const struct net_device *dev) |
| { |
| BUG(); |
| return NULL; |
| } |
| |
| static inline u16 vlan_dev_vlan_id(const struct net_device *dev) |
| { |
| BUG(); |
| return 0; |
| } |
| |
| static inline bool vlan_do_receive(struct sk_buff **skb) |
| { |
| return false; |
| } |
| |
| static inline struct sk_buff *vlan_untag(struct sk_buff *skb) |
| { |
| return skb; |
| } |
| |
| static inline int vlan_vid_add(struct net_device *dev, unsigned short vid) |
| { |
| return 0; |
| } |
| |
| static inline void vlan_vid_del(struct net_device *dev, unsigned short vid) |
| { |
| } |
| |
| static inline int vlan_vids_add_by_dev(struct net_device *dev, |
| const struct net_device *by_dev) |
| { |
| return 0; |
| } |
| |
| static inline void vlan_vids_del_by_dev(struct net_device *dev, |
| const struct net_device *by_dev) |
| { |
| } |
| |
| static inline bool vlan_uses_dev(const struct net_device *dev) |
| { |
| return false; |
| } |
| #endif |
| |
| /** |
| * vlan_insert_tag - regular VLAN tag inserting |
| * @skb: skbuff to tag |
| * @vlan_tci: VLAN TCI to insert |
| * |
| * Inserts the VLAN tag into @skb as part of the payload |
| * Returns a VLAN tagged skb. If a new skb is created, @skb is freed. |
| * |
| * Following the skb_unshare() example, in case of error, the calling function |
| * doesn't have to worry about freeing the original skb. |
| * |
| * Does not change skb->protocol so this function can be used during receive. |
| */ |
| static inline struct sk_buff *vlan_insert_tag(struct sk_buff *skb, u16 vlan_tci) |
| { |
| struct vlan_ethhdr *veth; |
| |
| if (skb_cow_head(skb, VLAN_HLEN) < 0) { |
| kfree_skb(skb); |
| return NULL; |
| } |
| veth = (struct vlan_ethhdr *)skb_push(skb, VLAN_HLEN); |
| |
| /* Move the mac addresses to the beginning of the new header. */ |
| memmove(skb->data, skb->data + VLAN_HLEN, 2 * ETH_ALEN); |
| skb->mac_header -= VLAN_HLEN; |
| |
| /* first, the ethernet type */ |
| veth->h_vlan_proto = htons(ETH_P_8021Q); |
| |
| /* now, the TCI */ |
| veth->h_vlan_TCI = htons(vlan_tci); |
| |
| return skb; |
| } |
| |
| /** |
| * __vlan_put_tag - regular VLAN tag inserting |
| * @skb: skbuff to tag |
| * @vlan_tci: VLAN TCI to insert |
| * |
| * Inserts the VLAN tag into @skb as part of the payload |
| * Returns a VLAN tagged skb. If a new skb is created, @skb is freed. |
| * |
| * Following the skb_unshare() example, in case of error, the calling function |
| * doesn't have to worry about freeing the original skb. |
| */ |
| static inline struct sk_buff *__vlan_put_tag(struct sk_buff *skb, u16 vlan_tci) |
| { |
| skb = vlan_insert_tag(skb, vlan_tci); |
| if (skb) |
| skb->protocol = htons(ETH_P_8021Q); |
| return skb; |
| } |
| |
| /** |
| * __vlan_hwaccel_put_tag - hardware accelerated VLAN inserting |
| * @skb: skbuff to tag |
| * @vlan_tci: VLAN TCI to insert |
| * |
| * Puts the VLAN TCI in @skb->vlan_tci and lets the device do the rest |
| */ |
| static inline struct sk_buff *__vlan_hwaccel_put_tag(struct sk_buff *skb, |
| u16 vlan_tci) |
| { |
| skb->vlan_tci = VLAN_TAG_PRESENT | vlan_tci; |
| return skb; |
| } |
| |
| #define HAVE_VLAN_PUT_TAG |
| |
| /** |
| * vlan_put_tag - inserts VLAN tag according to device features |
| * @skb: skbuff to tag |
| * @vlan_tci: VLAN TCI to insert |
| * |
| * Assumes skb->dev is the target that will xmit this frame. |
| * Returns a VLAN tagged skb. |
| */ |
| static inline struct sk_buff *vlan_put_tag(struct sk_buff *skb, u16 vlan_tci) |
| { |
| if (skb->dev->features & NETIF_F_HW_VLAN_CTAG_TX) { |
| return __vlan_hwaccel_put_tag(skb, vlan_tci); |
| } else { |
| return __vlan_put_tag(skb, vlan_tci); |
| } |
| } |
| |
| /** |
| * __vlan_get_tag - get the VLAN ID that is part of the payload |
| * @skb: skbuff to query |
| * @vlan_tci: buffer to store vlaue |
| * |
| * Returns error if the skb is not of VLAN type |
| */ |
| static inline int __vlan_get_tag(const struct sk_buff *skb, u16 *vlan_tci) |
| { |
| struct vlan_ethhdr *veth = (struct vlan_ethhdr *)skb->data; |
| |
| if (veth->h_vlan_proto != htons(ETH_P_8021Q)) { |
| return -EINVAL; |
| } |
| |
| *vlan_tci = ntohs(veth->h_vlan_TCI); |
| return 0; |
| } |
| |
| /** |
| * __vlan_hwaccel_get_tag - get the VLAN ID that is in @skb->cb[] |
| * @skb: skbuff to query |
| * @vlan_tci: buffer to store vlaue |
| * |
| * Returns error if @skb->vlan_tci is not set correctly |
| */ |
| static inline int __vlan_hwaccel_get_tag(const struct sk_buff *skb, |
| u16 *vlan_tci) |
| { |
| if (vlan_tx_tag_present(skb)) { |
| *vlan_tci = vlan_tx_tag_get(skb); |
| return 0; |
| } else { |
| *vlan_tci = 0; |
| return -EINVAL; |
| } |
| } |
| |
| #define HAVE_VLAN_GET_TAG |
| |
| /** |
| * vlan_get_tag - get the VLAN ID from the skb |
| * @skb: skbuff to query |
| * @vlan_tci: buffer to store vlaue |
| * |
| * Returns error if the skb is not VLAN tagged |
| */ |
| static inline int vlan_get_tag(const struct sk_buff *skb, u16 *vlan_tci) |
| { |
| if (skb->dev->features & NETIF_F_HW_VLAN_CTAG_TX) { |
| return __vlan_hwaccel_get_tag(skb, vlan_tci); |
| } else { |
| return __vlan_get_tag(skb, vlan_tci); |
| } |
| } |
| |
| /** |
| * vlan_get_protocol - get protocol EtherType. |
| * @skb: skbuff to query |
| * |
| * Returns the EtherType of the packet, regardless of whether it is |
| * vlan encapsulated (normal or hardware accelerated) or not. |
| */ |
| static inline __be16 vlan_get_protocol(const struct sk_buff *skb) |
| { |
| __be16 protocol = 0; |
| |
| if (vlan_tx_tag_present(skb) || |
| skb->protocol != cpu_to_be16(ETH_P_8021Q)) |
| protocol = skb->protocol; |
| else { |
| __be16 proto, *protop; |
| protop = skb_header_pointer(skb, offsetof(struct vlan_ethhdr, |
| h_vlan_encapsulated_proto), |
| sizeof(proto), &proto); |
| if (likely(protop)) |
| protocol = *protop; |
| } |
| |
| return protocol; |
| } |
| |
| static inline void vlan_set_encap_proto(struct sk_buff *skb, |
| struct vlan_hdr *vhdr) |
| { |
| __be16 proto; |
| unsigned short *rawp; |
| |
| /* |
| * Was a VLAN packet, grab the encapsulated protocol, which the layer |
| * three protocols care about. |
| */ |
| |
| proto = vhdr->h_vlan_encapsulated_proto; |
| if (ntohs(proto) >= ETH_P_802_3_MIN) { |
| skb->protocol = proto; |
| return; |
| } |
| |
| rawp = (unsigned short *)(vhdr + 1); |
| if (*rawp == 0xFFFF) |
| /* |
| * 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. |
| */ |
| skb->protocol = htons(ETH_P_802_3); |
| else |
| /* |
| * Real 802.2 LLC |
| */ |
| skb->protocol = htons(ETH_P_802_2); |
| } |
| #endif /* !(_LINUX_IF_VLAN_H_) */ |