319 lines
8.6 KiB
C
319 lines
8.6 KiB
C
|
/* This program is free software; you can redistribute it and/or modify
|
||
|
|
* it under the terms of the GNU General Public License version 2
|
||
|
|
* as published by the Free Software Foundation.
|
||
|
|
*
|
||
|
|
* This program is distributed in the hope that it will be useful,
|
||
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
|
|
* GNU General Public License for more details.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <net/6lowpan.h>
|
||
|
|
#include <net/ndisc.h>
|
||
|
|
#include <net/ieee802154_netdev.h>
|
||
|
|
#include <net/mac802154.h>
|
||
|
|
|
||
|
|
#include "6lowpan_i.h"
|
||
|
|
|
||
|
|
#define LOWPAN_FRAG1_HEAD_SIZE 0x4
|
||
|
|
#define LOWPAN_FRAGN_HEAD_SIZE 0x5
|
||
|
|
|
||
|
|
struct lowpan_addr_info {
|
||
|
|
struct ieee802154_addr daddr;
|
||
|
|
struct ieee802154_addr saddr;
|
||
|
|
};
|
||
|
|
|
||
|
|
static inline struct
|
||
|
|
lowpan_addr_info *lowpan_skb_priv(const struct sk_buff *skb)
|
||
|
|
{
|
||
|
|
WARN_ON_ONCE(skb_headroom(skb) < sizeof(struct lowpan_addr_info));
|
||
|
|
return (struct lowpan_addr_info *)(skb->data -
|
||
|
|
sizeof(struct lowpan_addr_info));
|
||
|
|
}
|
||
|
|
|
||
|
|
/* This callback will be called from AF_PACKET and IPv6 stack, the AF_PACKET
|
||
|
|
* sockets gives an 8 byte array for addresses only!
|
||
|
|
*
|
||
|
|
* TODO I think AF_PACKET DGRAM (sending/receiving) RAW (sending) makes no
|
||
|
|
* sense here. We should disable it, the right use-case would be AF_INET6
|
||
|
|
* RAW/DGRAM sockets.
|
||
|
|
*/
|
||
|
|
int lowpan_header_create(struct sk_buff *skb, struct net_device *ldev,
|
||
|
|
unsigned short type, const void *daddr,
|
||
|
|
const void *saddr, unsigned int len)
|
||
|
|
{
|
||
|
|
struct wpan_dev *wpan_dev = lowpan_802154_dev(ldev)->wdev->ieee802154_ptr;
|
||
|
|
struct lowpan_addr_info *info = lowpan_skb_priv(skb);
|
||
|
|
struct lowpan_802154_neigh *llneigh = NULL;
|
||
|
|
const struct ipv6hdr *hdr = ipv6_hdr(skb);
|
||
|
|
struct neighbour *n;
|
||
|
|
|
||
|
|
if (!daddr)
|
||
|
|
return -EINVAL;
|
||
|
|
|
||
|
|
/* TODO:
|
||
|
|
* if this package isn't ipv6 one, where should it be routed?
|
||
|
|
*/
|
||
|
|
if (type != ETH_P_IPV6)
|
||
|
|
return 0;
|
||
|
|
|
||
|
|
/* intra-pan communication */
|
||
|
|
info->saddr.pan_id = wpan_dev->pan_id;
|
||
|
|
info->daddr.pan_id = info->saddr.pan_id;
|
||
|
|
|
||
|
|
if (!memcmp(daddr, ldev->broadcast, EUI64_ADDR_LEN)) {
|
||
|
|
info->daddr.short_addr = cpu_to_le16(IEEE802154_ADDR_BROADCAST);
|
||
|
|
info->daddr.mode = IEEE802154_ADDR_SHORT;
|
||
|
|
} else {
|
||
|
|
__le16 short_addr = cpu_to_le16(IEEE802154_ADDR_SHORT_UNSPEC);
|
||
|
|
|
||
|
|
n = neigh_lookup(&nd_tbl, &hdr->daddr, ldev);
|
||
|
|
if (n) {
|
||
|
|
llneigh = lowpan_802154_neigh(neighbour_priv(n));
|
||
|
|
read_lock_bh(&n->lock);
|
||
|
|
short_addr = llneigh->short_addr;
|
||
|
|
read_unlock_bh(&n->lock);
|
||
|
|
}
|
||
|
|
|
||
|
|
if (llneigh &&
|
||
|
|
lowpan_802154_is_valid_src_short_addr(short_addr)) {
|
||
|
|
info->daddr.short_addr = short_addr;
|
||
|
|
info->daddr.mode = IEEE802154_ADDR_SHORT;
|
||
|
|
} else {
|
||
|
|
info->daddr.mode = IEEE802154_ADDR_LONG;
|
||
|
|
ieee802154_be64_to_le64(&info->daddr.extended_addr,
|
||
|
|
daddr);
|
||
|
|
}
|
||
|
|
|
||
|
|
if (n)
|
||
|
|
neigh_release(n);
|
||
|
|
}
|
||
|
|
|
||
|
|
if (!saddr) {
|
||
|
|
if (lowpan_802154_is_valid_src_short_addr(wpan_dev->short_addr)) {
|
||
|
|
info->saddr.mode = IEEE802154_ADDR_SHORT;
|
||
|
|
info->saddr.short_addr = wpan_dev->short_addr;
|
||
|
|
} else {
|
||
|
|
info->saddr.mode = IEEE802154_ADDR_LONG;
|
||
|
|
info->saddr.extended_addr = wpan_dev->extended_addr;
|
||
|
|
}
|
||
|
|
} else {
|
||
|
|
info->saddr.mode = IEEE802154_ADDR_LONG;
|
||
|
|
ieee802154_be64_to_le64(&info->saddr.extended_addr, saddr);
|
||
|
|
}
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static struct sk_buff*
|
||
|
|
lowpan_alloc_frag(struct sk_buff *skb, int size,
|
||
|
|
const struct ieee802154_hdr *master_hdr, bool frag1)
|
||
|
|
{
|
||
|
|
struct net_device *wdev = lowpan_802154_dev(skb->dev)->wdev;
|
||
|
|
struct sk_buff *frag;
|
||
|
|
int rc;
|
||
|
|
|
||
|
|
frag = alloc_skb(wdev->needed_headroom + wdev->needed_tailroom + size,
|
||
|
|
GFP_ATOMIC);
|
||
|
|
|
||
|
|
if (likely(frag)) {
|
||
|
|
frag->dev = wdev;
|
||
|
|
frag->priority = skb->priority;
|
||
|
|
skb_reserve(frag, wdev->needed_headroom);
|
||
|
|
skb_reset_network_header(frag);
|
||
|
|
*mac_cb(frag) = *mac_cb(skb);
|
||
|
|
|
||
|
|
if (frag1) {
|
||
|
|
memcpy(skb_put(frag, skb->mac_len),
|
||
|
|
skb_mac_header(skb), skb->mac_len);
|
||
|
|
} else {
|
||
|
|
rc = wpan_dev_hard_header(frag, wdev,
|
||
|
|
&master_hdr->dest,
|
||
|
|
&master_hdr->source, size);
|
||
|
|
if (rc < 0) {
|
||
|
|
kfree_skb(frag);
|
||
|
|
return ERR_PTR(rc);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
} else {
|
||
|
|
frag = ERR_PTR(-ENOMEM);
|
||
|
|
}
|
||
|
|
|
||
|
|
return frag;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int
|
||
|
|
lowpan_xmit_fragment(struct sk_buff *skb, const struct ieee802154_hdr *wpan_hdr,
|
||
|
|
u8 *frag_hdr, int frag_hdrlen,
|
||
|
|
int offset, int len, bool frag1)
|
||
|
|
{
|
||
|
|
struct sk_buff *frag;
|
||
|
|
|
||
|
|
raw_dump_inline(__func__, " fragment header", frag_hdr, frag_hdrlen);
|
||
|
|
|
||
|
|
frag = lowpan_alloc_frag(skb, frag_hdrlen + len, wpan_hdr, frag1);
|
||
|
|
if (IS_ERR(frag))
|
||
|
|
return PTR_ERR(frag);
|
||
|
|
|
||
|
|
memcpy(skb_put(frag, frag_hdrlen), frag_hdr, frag_hdrlen);
|
||
|
|
memcpy(skb_put(frag, len), skb_network_header(skb) + offset, len);
|
||
|
|
|
||
|
|
raw_dump_table(__func__, " fragment dump", frag->data, frag->len);
|
||
|
|
|
||
|
|
return dev_queue_xmit(frag);
|
||
|
|
}
|
||
|
|
|
||
|
|
static int
|
||
|
|
lowpan_xmit_fragmented(struct sk_buff *skb, struct net_device *ldev,
|
||
|
|
const struct ieee802154_hdr *wpan_hdr, u16 dgram_size,
|
||
|
|
u16 dgram_offset)
|
||
|
|
{
|
||
|
|
__be16 frag_tag;
|
||
|
|
u8 frag_hdr[5];
|
||
|
|
int frag_cap, frag_len, payload_cap, rc;
|
||
|
|
int skb_unprocessed, skb_offset;
|
||
|
|
|
||
|
|
frag_tag = htons(lowpan_802154_dev(ldev)->fragment_tag);
|
||
|
|
lowpan_802154_dev(ldev)->fragment_tag++;
|
||
|
|
|
||
|
|
frag_hdr[0] = LOWPAN_DISPATCH_FRAG1 | ((dgram_size >> 8) & 0x07);
|
||
|
|
frag_hdr[1] = dgram_size & 0xff;
|
||
|
|
memcpy(frag_hdr + 2, &frag_tag, sizeof(frag_tag));
|
||
|
|
|
||
|
|
payload_cap = ieee802154_max_payload(wpan_hdr);
|
||
|
|
|
||
|
|
frag_len = round_down(payload_cap - LOWPAN_FRAG1_HEAD_SIZE -
|
||
|
|
skb_network_header_len(skb), 8);
|
||
|
|
|
||
|
|
skb_offset = skb_network_header_len(skb);
|
||
|
|
skb_unprocessed = skb->len - skb->mac_len - skb_offset;
|
||
|
|
|
||
|
|
rc = lowpan_xmit_fragment(skb, wpan_hdr, frag_hdr,
|
||
|
|
LOWPAN_FRAG1_HEAD_SIZE, 0,
|
||
|
|
frag_len + skb_network_header_len(skb),
|
||
|
|
true);
|
||
|
|
if (rc) {
|
||
|
|
pr_debug("%s unable to send FRAG1 packet (tag: %d)",
|
||
|
|
__func__, ntohs(frag_tag));
|
||
|
|
goto err;
|
||
|
|
}
|
||
|
|
|
||
|
|
frag_hdr[0] &= ~LOWPAN_DISPATCH_FRAG1;
|
||
|
|
frag_hdr[0] |= LOWPAN_DISPATCH_FRAGN;
|
||
|
|
frag_cap = round_down(payload_cap - LOWPAN_FRAGN_HEAD_SIZE, 8);
|
||
|
|
|
||
|
|
do {
|
||
|
|
dgram_offset += frag_len;
|
||
|
|
skb_offset += frag_len;
|
||
|
|
skb_unprocessed -= frag_len;
|
||
|
|
frag_len = min(frag_cap, skb_unprocessed);
|
||
|
|
|
||
|
|
frag_hdr[4] = dgram_offset >> 3;
|
||
|
|
|
||
|
|
rc = lowpan_xmit_fragment(skb, wpan_hdr, frag_hdr,
|
||
|
|
LOWPAN_FRAGN_HEAD_SIZE, skb_offset,
|
||
|
|
frag_len, false);
|
||
|
|
if (rc) {
|
||
|
|
pr_debug("%s unable to send a FRAGN packet. (tag: %d, offset: %d)\n",
|
||
|
|
__func__, ntohs(frag_tag), skb_offset);
|
||
|
|
goto err;
|
||
|
|
}
|
||
|
|
} while (skb_unprocessed > frag_cap);
|
||
|
|
|
||
|
|
ldev->stats.tx_packets++;
|
||
|
|
ldev->stats.tx_bytes += dgram_size;
|
||
|
|
consume_skb(skb);
|
||
|
|
return NET_XMIT_SUCCESS;
|
||
|
|
|
||
|
|
err:
|
||
|
|
kfree_skb(skb);
|
||
|
|
return rc;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int lowpan_header(struct sk_buff *skb, struct net_device *ldev,
|
||
|
|
u16 *dgram_size, u16 *dgram_offset)
|
||
|
|
{
|
||
|
|
struct wpan_dev *wpan_dev = lowpan_802154_dev(ldev)->wdev->ieee802154_ptr;
|
||
|
|
struct ieee802154_mac_cb *cb = mac_cb_init(skb);
|
||
|
|
struct lowpan_addr_info info;
|
||
|
|
|
||
|
|
memcpy(&info, lowpan_skb_priv(skb), sizeof(info));
|
||
|
|
|
||
|
|
*dgram_size = skb->len;
|
||
|
|
lowpan_header_compress(skb, ldev, &info.daddr, &info.saddr);
|
||
|
|
/* dgram_offset = (saved bytes after compression) + lowpan header len */
|
||
|
|
*dgram_offset = (*dgram_size - skb->len) + skb_network_header_len(skb);
|
||
|
|
|
||
|
|
cb->type = IEEE802154_FC_TYPE_DATA;
|
||
|
|
|
||
|
|
if (info.daddr.mode == IEEE802154_ADDR_SHORT &&
|
||
|
|
ieee802154_is_broadcast_short_addr(info.daddr.short_addr))
|
||
|
|
cb->ackreq = false;
|
||
|
|
else
|
||
|
|
cb->ackreq = wpan_dev->ackreq;
|
||
|
|
|
||
|
|
return wpan_dev_hard_header(skb, lowpan_802154_dev(ldev)->wdev,
|
||
|
|
&info.daddr, &info.saddr, 0);
|
||
|
|
}
|
||
|
|
|
||
|
|
netdev_tx_t lowpan_xmit(struct sk_buff *skb, struct net_device *ldev)
|
||
|
|
{
|
||
|
|
struct ieee802154_hdr wpan_hdr;
|
||
|
|
int max_single, ret;
|
||
|
|
u16 dgram_size, dgram_offset;
|
||
|
|
|
||
|
|
pr_debug("package xmit\n");
|
||
|
|
|
||
|
|
WARN_ON_ONCE(skb->len > IPV6_MIN_MTU);
|
||
|
|
|
||
|
|
/* We must take a copy of the skb before we modify/replace the ipv6
|
||
|
|
* header as the header could be used elsewhere
|
||
|
|
*/
|
||
|
|
if (unlikely(skb_headroom(skb) < ldev->needed_headroom ||
|
||
|
|
skb_tailroom(skb) < ldev->needed_tailroom)) {
|
||
|
|
struct sk_buff *nskb;
|
||
|
|
|
||
|
|
nskb = skb_copy_expand(skb, ldev->needed_headroom,
|
||
|
|
ldev->needed_tailroom, GFP_ATOMIC);
|
||
|
|
if (likely(nskb)) {
|
||
|
|
consume_skb(skb);
|
||
|
|
skb = nskb;
|
||
|
|
} else {
|
||
|
|
kfree_skb(skb);
|
||
|
|
return NET_XMIT_DROP;
|
||
|
|
}
|
||
|
|
} else {
|
||
|
|
skb = skb_unshare(skb, GFP_ATOMIC);
|
||
|
|
if (!skb)
|
||
|
|
return NET_XMIT_DROP;
|
||
|
|
}
|
||
|
|
|
||
|
|
ret = lowpan_header(skb, ldev, &dgram_size, &dgram_offset);
|
||
|
|
if (ret < 0) {
|
||
|
|
kfree_skb(skb);
|
||
|
|
return NET_XMIT_DROP;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (ieee802154_hdr_peek(skb, &wpan_hdr) < 0) {
|
||
|
|
kfree_skb(skb);
|
||
|
|
return NET_XMIT_DROP;
|
||
|
|
}
|
||
|
|
|
||
|
|
max_single = ieee802154_max_payload(&wpan_hdr);
|
||
|
|
|
||
|
|
if (skb_tail_pointer(skb) - skb_network_header(skb) <= max_single) {
|
||
|
|
skb->dev = lowpan_802154_dev(ldev)->wdev;
|
||
|
|
ldev->stats.tx_packets++;
|
||
|
|
ldev->stats.tx_bytes += dgram_size;
|
||
|
|
return dev_queue_xmit(skb);
|
||
|
|
} else {
|
||
|
|
netdev_tx_t rc;
|
||
|
|
|
||
|
|
pr_debug("frame is too big, fragmentation is needed\n");
|
||
|
|
rc = lowpan_xmit_fragmented(skb, ldev, &wpan_hdr, dgram_size,
|
||
|
|
dgram_offset);
|
||
|
|
|
||
|
|
return rc < 0 ? NET_XMIT_DROP : rc;
|
||
|
|
}
|
||
|
|
}
|