1 /* This program is free software; you can redistribute it and/or modify
2 * it under the terms of the GNU General Public License version 2
3 * as published by the Free Software Foundation.
5 * This program is distributed in the hope that it will be useful,
6 * but WITHOUT ANY WARRANTY; without even the implied warranty of
7 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
8 * GNU General Public License for more details.
11 #include <net/6lowpan.h>
12 #include <net/ieee802154_netdev.h>
13 #include <net/mac802154.h>
15 #include "6lowpan_i.h"
17 /* don't save pan id, it's intra pan */
21 /* IPv6 needs big endian here */
27 struct lowpan_addr_info {
28 struct lowpan_addr daddr;
29 struct lowpan_addr saddr;
33 lowpan_addr_info *lowpan_skb_priv(const struct sk_buff *skb)
35 WARN_ON_ONCE(skb_headroom(skb) < sizeof(struct lowpan_addr_info));
36 return (struct lowpan_addr_info *)(skb->data -
37 sizeof(struct lowpan_addr_info));
40 /* This callback will be called from AF_PACKET and IPv6 stack, the AF_PACKET
41 * sockets gives an 8 byte array for addresses only!
43 * TODO I think AF_PACKET DGRAM (sending/receiving) RAW (sending) makes no
44 * sense here. We should disable it, the right use-case would be AF_INET6
47 int lowpan_header_create(struct sk_buff *skb, struct net_device *ldev,
48 unsigned short type, const void *_daddr,
49 const void *_saddr, unsigned int len)
51 const u8 *saddr = _saddr;
52 const u8 *daddr = _daddr;
53 struct lowpan_addr_info *info;
56 * if this package isn't ipv6 one, where should it be routed?
58 if (type != ETH_P_IPV6)
62 saddr = ldev->dev_addr;
64 raw_dump_inline(__func__, "saddr", (unsigned char *)saddr, 8);
65 raw_dump_inline(__func__, "daddr", (unsigned char *)daddr, 8);
67 info = lowpan_skb_priv(skb);
69 /* TODO: Currently we only support extended_addr */
70 info->daddr.mode = IEEE802154_ADDR_LONG;
71 memcpy(&info->daddr.u.extended_addr, daddr,
72 sizeof(info->daddr.u.extended_addr));
73 info->saddr.mode = IEEE802154_ADDR_LONG;
74 memcpy(&info->saddr.u.extended_addr, saddr,
75 sizeof(info->daddr.u.extended_addr));
80 static struct sk_buff*
81 lowpan_alloc_frag(struct sk_buff *skb, int size,
82 const struct ieee802154_hdr *master_hdr, bool frag1)
84 struct net_device *wdev = lowpan_dev_info(skb->dev)->wdev;
88 frag = alloc_skb(wdev->needed_headroom + wdev->needed_tailroom + size,
93 frag->priority = skb->priority;
94 skb_reserve(frag, wdev->needed_headroom);
95 skb_reset_network_header(frag);
96 *mac_cb(frag) = *mac_cb(skb);
99 memcpy(skb_put(frag, skb->mac_len),
100 skb_mac_header(skb), skb->mac_len);
102 rc = wpan_dev_hard_header(frag, wdev,
104 &master_hdr->source, size);
111 frag = ERR_PTR(-ENOMEM);
118 lowpan_xmit_fragment(struct sk_buff *skb, const struct ieee802154_hdr *wpan_hdr,
119 u8 *frag_hdr, int frag_hdrlen,
120 int offset, int len, bool frag1)
122 struct sk_buff *frag;
124 raw_dump_inline(__func__, " fragment header", frag_hdr, frag_hdrlen);
126 frag = lowpan_alloc_frag(skb, frag_hdrlen + len, wpan_hdr, frag1);
128 return PTR_ERR(frag);
130 memcpy(skb_put(frag, frag_hdrlen), frag_hdr, frag_hdrlen);
131 memcpy(skb_put(frag, len), skb_network_header(skb) + offset, len);
133 raw_dump_table(__func__, " fragment dump", frag->data, frag->len);
135 return dev_queue_xmit(frag);
139 lowpan_xmit_fragmented(struct sk_buff *skb, struct net_device *ldev,
140 const struct ieee802154_hdr *wpan_hdr, u16 dgram_size,
145 int frag_cap, frag_len, payload_cap, rc;
146 int skb_unprocessed, skb_offset;
148 frag_tag = htons(lowpan_dev_info(ldev)->fragment_tag);
149 lowpan_dev_info(ldev)->fragment_tag++;
151 frag_hdr[0] = LOWPAN_DISPATCH_FRAG1 | ((dgram_size >> 8) & 0x07);
152 frag_hdr[1] = dgram_size & 0xff;
153 memcpy(frag_hdr + 2, &frag_tag, sizeof(frag_tag));
155 payload_cap = ieee802154_max_payload(wpan_hdr);
157 frag_len = round_down(payload_cap - LOWPAN_FRAG1_HEAD_SIZE -
158 skb_network_header_len(skb), 8);
160 skb_offset = skb_network_header_len(skb);
161 skb_unprocessed = skb->len - skb->mac_len - skb_offset;
163 rc = lowpan_xmit_fragment(skb, wpan_hdr, frag_hdr,
164 LOWPAN_FRAG1_HEAD_SIZE, 0,
165 frag_len + skb_network_header_len(skb),
168 pr_debug("%s unable to send FRAG1 packet (tag: %d)",
169 __func__, ntohs(frag_tag));
173 frag_hdr[0] &= ~LOWPAN_DISPATCH_FRAG1;
174 frag_hdr[0] |= LOWPAN_DISPATCH_FRAGN;
175 frag_cap = round_down(payload_cap - LOWPAN_FRAGN_HEAD_SIZE, 8);
178 dgram_offset += frag_len;
179 skb_offset += frag_len;
180 skb_unprocessed -= frag_len;
181 frag_len = min(frag_cap, skb_unprocessed);
183 frag_hdr[4] = dgram_offset >> 3;
185 rc = lowpan_xmit_fragment(skb, wpan_hdr, frag_hdr,
186 LOWPAN_FRAGN_HEAD_SIZE, skb_offset,
189 pr_debug("%s unable to send a FRAGN packet. (tag: %d, offset: %d)\n",
190 __func__, ntohs(frag_tag), skb_offset);
193 } while (skb_unprocessed > frag_cap);
195 ldev->stats.tx_packets++;
196 ldev->stats.tx_bytes += dgram_size;
198 return NET_XMIT_SUCCESS;
205 static int lowpan_header(struct sk_buff *skb, struct net_device *ldev,
206 u16 *dgram_size, u16 *dgram_offset)
208 struct wpan_dev *wpan_dev = lowpan_dev_info(ldev)->wdev->ieee802154_ptr;
209 struct ieee802154_addr sa, da;
210 struct ieee802154_mac_cb *cb = mac_cb_init(skb);
211 struct lowpan_addr_info info;
214 memcpy(&info, lowpan_skb_priv(skb), sizeof(info));
216 /* TODO: Currently we only support extended_addr */
217 daddr = &info.daddr.u.extended_addr;
218 saddr = &info.saddr.u.extended_addr;
220 *dgram_size = skb->len;
221 lowpan_header_compress(skb, ldev, ETH_P_IPV6, daddr, saddr, skb->len);
222 /* dgram_offset = (saved bytes after compression) + lowpan header len */
223 *dgram_offset = (*dgram_size - skb->len) + skb_network_header_len(skb);
225 cb->type = IEEE802154_FC_TYPE_DATA;
227 /* prepare wpan address data */
228 sa.mode = IEEE802154_ADDR_LONG;
229 sa.pan_id = wpan_dev->pan_id;
230 sa.extended_addr = ieee802154_devaddr_from_raw(saddr);
232 /* intra-PAN communications */
233 da.pan_id = sa.pan_id;
235 /* if the destination address is the broadcast address, use the
236 * corresponding short address
238 if (lowpan_is_addr_broadcast((const u8 *)daddr)) {
239 da.mode = IEEE802154_ADDR_SHORT;
240 da.short_addr = cpu_to_le16(IEEE802154_ADDR_BROADCAST);
243 da.mode = IEEE802154_ADDR_LONG;
244 da.extended_addr = ieee802154_devaddr_from_raw(daddr);
245 cb->ackreq = wpan_dev->ackreq;
248 return wpan_dev_hard_header(skb, lowpan_dev_info(ldev)->wdev, &da, &sa,
252 netdev_tx_t lowpan_xmit(struct sk_buff *skb, struct net_device *ldev)
254 struct ieee802154_hdr wpan_hdr;
256 u16 dgram_size, dgram_offset;
258 pr_debug("package xmit\n");
260 WARN_ON_ONCE(skb->len > IPV6_MIN_MTU);
262 /* We must take a copy of the skb before we modify/replace the ipv6
263 * header as the header could be used elsewhere
265 skb = skb_unshare(skb, GFP_ATOMIC);
267 return NET_XMIT_DROP;
269 ret = lowpan_header(skb, ldev, &dgram_size, &dgram_offset);
272 return NET_XMIT_DROP;
275 if (ieee802154_hdr_peek(skb, &wpan_hdr) < 0) {
277 return NET_XMIT_DROP;
280 max_single = ieee802154_max_payload(&wpan_hdr);
282 if (skb_tail_pointer(skb) - skb_network_header(skb) <= max_single) {
283 skb->dev = lowpan_dev_info(ldev)->wdev;
284 ldev->stats.tx_packets++;
285 ldev->stats.tx_bytes += dgram_size;
286 return dev_queue_xmit(skb);
290 pr_debug("frame is too big, fragmentation is needed\n");
291 rc = lowpan_xmit_fragmented(skb, ldev, &wpan_hdr, dgram_size,
294 return rc < 0 ? NET_XMIT_DROP : rc;