2 * Copyright 2011, Siemens AG
3 * written by Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
7 * Based on patches from Jon Smirl <jonsmirl@gmail.com>
8 * Copyright (c) 2011 Jon Smirl <jonsmirl@gmail.com>
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2
12 * as published by the Free Software Foundation.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License along
20 * with this program; if not, write to the Free Software Foundation, Inc.,
21 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
24 /* Jon's code is based on 6lowpan implementation for Contiki which is:
25 * Copyright (c) 2008, Swedish Institute of Computer Science.
26 * All rights reserved.
28 * Redistribution and use in source and binary forms, with or without
29 * modification, are permitted provided that the following conditions
31 * 1. Redistributions of source code must retain the above copyright
32 * notice, this list of conditions and the following disclaimer.
33 * 2. Redistributions in binary form must reproduce the above copyright
34 * notice, this list of conditions and the following disclaimer in the
35 * documentation and/or other materials provided with the distribution.
36 * 3. Neither the name of the Institute nor the names of its contributors
37 * may be used to endorse or promote products derived from this software
38 * without specific prior written permission.
40 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
41 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
43 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
44 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
45 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
46 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
48 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
49 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
53 #include <linux/bitops.h>
54 #include <linux/if_arp.h>
55 #include <linux/module.h>
56 #include <linux/moduleparam.h>
57 #include <linux/netdevice.h>
58 #include <linux/etherdevice.h>
59 #include <net/af_ieee802154.h>
60 #include <net/ieee802154.h>
61 #include <net/ieee802154_netdev.h>
66 /* TTL uncompression values */
67 static const u8 lowpan_ttl_values[] = {0, 1, 64, 255};
69 static LIST_HEAD(lowpan_devices);
72 * Uncompression of linklocal:
73 * 0 -> 16 bytes from packet
74 * 1 -> 2 bytes from prefix - bunch of zeroes and 8 from packet
75 * 2 -> 2 bytes from prefix - zeroes + 2 from packet
76 * 3 -> 2 bytes from prefix - infer 8 bytes from lladdr
78 * NOTE: => the uncompress function does change 0xf to 0x10
79 * NOTE: 0x00 => no-autoconfig => unspecified
81 static const u8 lowpan_unc_llconf[] = {0x0f, 0x28, 0x22, 0x20};
84 * Uncompression of ctx-based:
85 * 0 -> 0 bits from packet [unspecified / reserved]
86 * 1 -> 8 bytes from prefix - bunch of zeroes and 8 from packet
87 * 2 -> 8 bytes from prefix - zeroes + 2 from packet
88 * 3 -> 8 bytes from prefix - infer 8 bytes from lladdr
90 static const u8 lowpan_unc_ctxconf[] = {0x00, 0x88, 0x82, 0x80};
93 * Uncompression of ctx-base
94 * 0 -> 0 bits from packet
95 * 1 -> 2 bytes from prefix - bunch of zeroes 5 from packet
96 * 2 -> 2 bytes from prefix - zeroes + 3 from packet
97 * 3 -> 2 bytes from prefix - infer 1 bytes from lladdr
99 static const u8 lowpan_unc_mxconf[] = {0x0f, 0x25, 0x23, 0x21};
101 /* Link local prefix */
102 static const u8 lowpan_llprefix[] = {0xfe, 0x80};
104 /* private device info */
105 struct lowpan_dev_info {
106 struct net_device *real_dev; /* real WPAN device ptr */
107 struct mutex dev_list_mtx; /* mutex for list ops */
110 struct lowpan_dev_record {
111 struct net_device *ldev;
112 struct list_head list;
115 struct lowpan_fragment {
116 struct sk_buff *skb; /* skb to be assembled */
117 spinlock_t lock; /* concurency lock */
118 u16 length; /* length to be assemled */
119 u32 bytes_rcv; /* bytes received */
120 u16 tag; /* current fragment tag */
121 struct timer_list timer; /* assembling timer */
122 struct list_head list; /* fragments list */
125 static unsigned short fragment_tag;
126 static LIST_HEAD(lowpan_fragments);
127 spinlock_t flist_lock;
130 lowpan_dev_info *lowpan_dev_info(const struct net_device *dev)
132 return netdev_priv(dev);
135 static inline void lowpan_address_flip(u8 *src, u8 *dest)
138 for (i = 0; i < IEEE802154_ADDR_LEN; i++)
139 (dest)[IEEE802154_ADDR_LEN - i - 1] = (src)[i];
142 /* list of all 6lowpan devices, uses for package delivering */
143 /* print data in line */
144 static inline void lowpan_raw_dump_inline(const char *caller, char *msg,
145 unsigned char *buf, int len)
149 pr_debug("(%s) %s: ", caller, msg);
150 print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_NONE,
151 16, 1, buf, len, false);
156 * print data in a table format:
158 * addr: xx xx xx xx xx xx
159 * addr: xx xx xx xx xx xx
162 static inline void lowpan_raw_dump_table(const char *caller, char *msg,
163 unsigned char *buf, int len)
167 pr_debug("(%s) %s:\n", caller, msg);
168 print_hex_dump(KERN_DEBUG, "\t", DUMP_PREFIX_OFFSET,
169 16, 1, buf, len, false);
174 lowpan_compress_addr_64(u8 **hc06_ptr, u8 shift, const struct in6_addr *ipaddr,
175 const unsigned char *lladdr)
179 if (is_addr_mac_addr_based(ipaddr, lladdr))
180 val = 3; /* 0-bits */
181 else if (lowpan_is_iid_16_bit_compressable(ipaddr)) {
182 /* compress IID to 16 bits xxxx::XXXX */
183 memcpy(*hc06_ptr, &ipaddr->s6_addr16[7], 2);
185 val = 2; /* 16-bits */
187 /* do not compress IID => xxxx::IID */
188 memcpy(*hc06_ptr, &ipaddr->s6_addr16[4], 8);
190 val = 1; /* 64-bits */
193 return rol8(val, shift);
197 lowpan_uip_ds6_set_addr_iid(struct in6_addr *ipaddr, unsigned char *lladdr)
199 memcpy(&ipaddr->s6_addr[8], lladdr, IEEE802154_ADDR_LEN);
200 /* second bit-flip (Universe/Local) is done according RFC2464 */
201 ipaddr->s6_addr[8] ^= 0x02;
205 * Uncompress addresses based on a prefix and a postfix with zeroes in
206 * between. If the postfix is zero in length it will use the link address
207 * to configure the IP address (autoconf style).
208 * pref_post_count takes a byte where the first nibble specify prefix count
209 * and the second postfix count (NOTE: 15/0xf => 16 bytes copy).
212 lowpan_uncompress_addr(struct sk_buff *skb, struct in6_addr *ipaddr,
213 u8 const *prefix, u8 pref_post_count, unsigned char *lladdr)
215 u8 prefcount = pref_post_count >> 4;
216 u8 postcount = pref_post_count & 0x0f;
218 /* full nibble 15 => 16 */
219 prefcount = (prefcount == 15 ? 16 : prefcount);
220 postcount = (postcount == 15 ? 16 : postcount);
223 lowpan_raw_dump_inline(__func__, "linklocal address",
224 lladdr, IEEE802154_ADDR_LEN);
226 memcpy(ipaddr, prefix, prefcount);
228 if (prefcount + postcount < 16)
229 memset(&ipaddr->s6_addr[prefcount], 0,
230 16 - (prefcount + postcount));
233 memcpy(&ipaddr->s6_addr[16 - postcount], skb->data, postcount);
234 skb_pull(skb, postcount);
235 } else if (prefcount > 0) {
239 /* no IID based configuration if no prefix and no data */
240 lowpan_uip_ds6_set_addr_iid(ipaddr, lladdr);
243 pr_debug("(%s): uncompressing %d + %d => ", __func__, prefcount,
245 lowpan_raw_dump_inline(NULL, NULL, ipaddr->s6_addr, 16);
251 lowpan_compress_udp_header(u8 **hc06_ptr, struct sk_buff *skb)
253 struct udphdr *uh = udp_hdr(skb);
255 pr_debug("(%s): UDP header compression\n", __func__);
257 if (((uh->source & LOWPAN_NHC_UDP_4BIT_MASK) ==
258 LOWPAN_NHC_UDP_4BIT_PORT) &&
259 ((uh->dest & LOWPAN_NHC_UDP_4BIT_MASK) ==
260 LOWPAN_NHC_UDP_4BIT_PORT)) {
261 pr_debug("(%s): both ports compression to 4 bits\n", __func__);
262 **hc06_ptr = LOWPAN_NHC_UDP_CS_P_11;
263 **(hc06_ptr + 1) = /* subtraction is faster */
264 (u8)((uh->dest - LOWPAN_NHC_UDP_4BIT_PORT) +
265 ((uh->source & LOWPAN_NHC_UDP_4BIT_PORT) << 4));
267 } else if ((uh->dest & LOWPAN_NHC_UDP_8BIT_MASK) ==
268 LOWPAN_NHC_UDP_8BIT_PORT) {
269 pr_debug("(%s): remove 8 bits of dest\n", __func__);
270 **hc06_ptr = LOWPAN_NHC_UDP_CS_P_01;
271 memcpy(*hc06_ptr + 1, &uh->source, 2);
272 **(hc06_ptr + 3) = (u8)(uh->dest - LOWPAN_NHC_UDP_8BIT_PORT);
274 } else if ((uh->source & LOWPAN_NHC_UDP_8BIT_MASK) ==
275 LOWPAN_NHC_UDP_8BIT_PORT) {
276 pr_debug("(%s): remove 8 bits of source\n", __func__);
277 **hc06_ptr = LOWPAN_NHC_UDP_CS_P_10;
278 memcpy(*hc06_ptr + 1, &uh->dest, 2);
279 **(hc06_ptr + 3) = (u8)(uh->source - LOWPAN_NHC_UDP_8BIT_PORT);
282 pr_debug("(%s): can't compress header\n", __func__);
283 **hc06_ptr = LOWPAN_NHC_UDP_CS_P_00;
284 memcpy(*hc06_ptr + 1, &uh->source, 2);
285 memcpy(*hc06_ptr + 3, &uh->dest, 2);
289 /* checksum is always inline */
290 memcpy(*hc06_ptr, &uh->check, 2);
294 static u8 lowpan_fetch_skb_u8(struct sk_buff *skb)
304 static u16 lowpan_fetch_skb_u16(struct sk_buff *skb)
308 BUG_ON(!pskb_may_pull(skb, 2));
310 ret = skb->data[0] | (skb->data[1] << 8);
316 lowpan_uncompress_udp_header(struct sk_buff *skb)
318 struct udphdr *uh = udp_hdr(skb);
321 tmp = lowpan_fetch_skb_u8(skb);
323 if ((tmp & LOWPAN_NHC_UDP_MASK) == LOWPAN_NHC_UDP_ID) {
324 pr_debug("(%s): UDP header uncompression\n", __func__);
325 switch (tmp & LOWPAN_NHC_UDP_CS_P_11) {
326 case LOWPAN_NHC_UDP_CS_P_00:
327 memcpy(&uh->source, &skb->data[0], 2);
328 memcpy(&uh->dest, &skb->data[2], 2);
331 case LOWPAN_NHC_UDP_CS_P_01:
332 memcpy(&uh->source, &skb->data[0], 2);
334 skb->data[2] + LOWPAN_NHC_UDP_8BIT_PORT;
337 case LOWPAN_NHC_UDP_CS_P_10:
338 uh->source = skb->data[0] + LOWPAN_NHC_UDP_8BIT_PORT;
339 memcpy(&uh->dest, &skb->data[1], 2);
342 case LOWPAN_NHC_UDP_CS_P_11:
344 LOWPAN_NHC_UDP_4BIT_PORT + (skb->data[0] >> 4);
346 LOWPAN_NHC_UDP_4BIT_PORT + (skb->data[0] & 0x0f);
350 pr_debug("(%s) ERROR: unknown UDP format\n", __func__);
355 pr_debug("(%s): uncompressed UDP ports: src = %d, dst = %d\n",
356 __func__, uh->source, uh->dest);
359 memcpy(&uh->check, &skb->data[0], 2);
362 pr_debug("(%s): ERROR: unsupported NH format\n", __func__);
371 static int lowpan_header_create(struct sk_buff *skb,
372 struct net_device *dev,
373 unsigned short type, const void *_daddr,
374 const void *_saddr, unsigned int len)
376 u8 tmp, iphc0, iphc1, *hc06_ptr;
378 const u8 *saddr = _saddr;
379 const u8 *daddr = _daddr;
381 struct ieee802154_addr sa, da;
383 if (type != ETH_P_IPV6)
386 * if this package isn't ipv6 one, where should it be routed?
388 head = kzalloc(100, GFP_KERNEL);
395 pr_debug("(%s): IPv6 header dump:\n\tversion = %d\n\tlength = %d\n"
396 "\tnexthdr = 0x%02x\n\thop_lim = %d\n", __func__,
397 hdr->version, ntohs(hdr->payload_len), hdr->nexthdr,
400 lowpan_raw_dump_table(__func__, "raw skb network header dump",
401 skb_network_header(skb), sizeof(struct ipv6hdr));
404 saddr = dev->dev_addr;
406 lowpan_raw_dump_inline(__func__, "saddr", (unsigned char *)saddr, 8);
409 * As we copy some bit-length fields, in the IPHC encoding bytes,
410 * we sometimes use |=
411 * If the field is 0, and the current bit value in memory is 1,
412 * this does not work. We therefore reset the IPHC encoding here
414 iphc0 = LOWPAN_DISPATCH_IPHC;
417 /* TODO: context lookup */
419 lowpan_raw_dump_inline(__func__, "daddr", (unsigned char *)daddr, 8);
422 * Traffic class, flow label
423 * If flow label is 0, compress it. If traffic class is 0, compress it
424 * We have to process both in the same time as the offset of traffic
425 * class depends on the presence of version and flow label
428 /* hc06 format of TC is ECN | DSCP , original one is DSCP | ECN */
429 tmp = (hdr->priority << 4) | (hdr->flow_lbl[0] >> 4);
430 tmp = ((tmp & 0x03) << 6) | (tmp >> 2);
432 if (((hdr->flow_lbl[0] & 0x0F) == 0) &&
433 (hdr->flow_lbl[1] == 0) && (hdr->flow_lbl[2] == 0)) {
434 /* flow label can be compressed */
435 iphc0 |= LOWPAN_IPHC_FL_C;
436 if ((hdr->priority == 0) &&
437 ((hdr->flow_lbl[0] & 0xF0) == 0)) {
438 /* compress (elide) all */
439 iphc0 |= LOWPAN_IPHC_TC_C;
441 /* compress only the flow label */
446 /* Flow label cannot be compressed */
447 if ((hdr->priority == 0) &&
448 ((hdr->flow_lbl[0] & 0xF0) == 0)) {
449 /* compress only traffic class */
450 iphc0 |= LOWPAN_IPHC_TC_C;
451 *hc06_ptr = (tmp & 0xc0) | (hdr->flow_lbl[0] & 0x0F);
452 memcpy(hc06_ptr + 1, &hdr->flow_lbl[1], 2);
455 /* compress nothing */
456 memcpy(hc06_ptr, &hdr, 4);
457 /* replace the top byte with new ECN | DSCP format */
463 /* NOTE: payload length is always compressed */
465 /* Next Header is compress if UDP */
466 if (hdr->nexthdr == UIP_PROTO_UDP)
467 iphc0 |= LOWPAN_IPHC_NH_C;
469 if ((iphc0 & LOWPAN_IPHC_NH_C) == 0) {
470 *hc06_ptr = hdr->nexthdr;
476 * if 1: compress, encoding is 01
477 * if 64: compress, encoding is 10
478 * if 255: compress, encoding is 11
479 * else do not compress
481 switch (hdr->hop_limit) {
483 iphc0 |= LOWPAN_IPHC_TTL_1;
486 iphc0 |= LOWPAN_IPHC_TTL_64;
489 iphc0 |= LOWPAN_IPHC_TTL_255;
492 *hc06_ptr = hdr->hop_limit;
496 /* source address compression */
497 if (is_addr_unspecified(&hdr->saddr)) {
498 pr_debug("(%s): source address is unspecified, setting SAC\n",
500 iphc1 |= LOWPAN_IPHC_SAC;
501 /* TODO: context lookup */
502 } else if (is_addr_link_local(&hdr->saddr)) {
503 pr_debug("(%s): source address is link-local\n", __func__);
504 iphc1 |= lowpan_compress_addr_64(&hc06_ptr,
505 LOWPAN_IPHC_SAM_BIT, &hdr->saddr, saddr);
507 pr_debug("(%s): send the full source address\n", __func__);
508 memcpy(hc06_ptr, &hdr->saddr.s6_addr16[0], 16);
512 /* destination address compression */
513 if (is_addr_mcast(&hdr->daddr)) {
514 pr_debug("(%s): destination address is multicast", __func__);
515 iphc1 |= LOWPAN_IPHC_M;
516 if (lowpan_is_mcast_addr_compressable8(&hdr->daddr)) {
517 pr_debug("compressed to 1 octet\n");
518 iphc1 |= LOWPAN_IPHC_DAM_11;
520 *hc06_ptr = hdr->daddr.s6_addr[15];
522 } else if (lowpan_is_mcast_addr_compressable32(&hdr->daddr)) {
523 pr_debug("compressed to 4 octets\n");
524 iphc1 |= LOWPAN_IPHC_DAM_10;
525 /* second byte + the last three */
526 *hc06_ptr = hdr->daddr.s6_addr[1];
527 memcpy(hc06_ptr + 1, &hdr->daddr.s6_addr[13], 3);
529 } else if (lowpan_is_mcast_addr_compressable48(&hdr->daddr)) {
530 pr_debug("compressed to 6 octets\n");
531 iphc1 |= LOWPAN_IPHC_DAM_01;
532 /* second byte + the last five */
533 *hc06_ptr = hdr->daddr.s6_addr[1];
534 memcpy(hc06_ptr + 1, &hdr->daddr.s6_addr[11], 5);
537 pr_debug("using full address\n");
538 iphc1 |= LOWPAN_IPHC_DAM_00;
539 memcpy(hc06_ptr, &hdr->daddr.s6_addr[0], 16);
543 pr_debug("(%s): destination address is unicast: ", __func__);
544 /* TODO: context lookup */
545 if (is_addr_link_local(&hdr->daddr)) {
546 pr_debug("destination address is link-local\n");
547 iphc1 |= lowpan_compress_addr_64(&hc06_ptr,
548 LOWPAN_IPHC_DAM_BIT, &hdr->daddr, daddr);
550 pr_debug("using full address\n");
551 memcpy(hc06_ptr, &hdr->daddr.s6_addr16[0], 16);
556 /* UDP header compression */
557 if (hdr->nexthdr == UIP_PROTO_UDP)
558 lowpan_compress_udp_header(&hc06_ptr, skb);
563 skb_pull(skb, sizeof(struct ipv6hdr));
564 memcpy(skb_push(skb, hc06_ptr - head), head, hc06_ptr - head);
568 lowpan_raw_dump_table(__func__, "raw skb data dump", skb->data,
572 * NOTE1: I'm still unsure about the fact that compression and WPAN
573 * header are created here and not later in the xmit. So wait for
574 * an opinion of net maintainers.
577 * NOTE2: to be absolutely correct, we must derive PANid information
578 * from MAC subif of the 'dev' and 'real_dev' network devices, but
579 * this isn't implemented in mainline yet, so currently we assign 0xff
582 /* prepare wpan address data */
583 sa.addr_type = IEEE802154_ADDR_LONG;
586 da.addr_type = IEEE802154_ADDR_LONG;
589 memcpy(&(da.hwaddr), daddr, 8);
590 memcpy(&(sa.hwaddr), saddr, 8);
592 mac_cb(skb)->flags = IEEE802154_FC_TYPE_DATA;
594 return dev_hard_header(skb, lowpan_dev_info(dev)->real_dev,
595 type, (void *)&da, (void *)&sa, skb->len);
599 static int lowpan_skb_deliver(struct sk_buff *skb, struct ipv6hdr *hdr)
602 struct lowpan_dev_record *entry;
603 int stat = NET_RX_SUCCESS;
605 new = skb_copy_expand(skb, sizeof(struct ipv6hdr), skb_tailroom(skb),
612 skb_push(new, sizeof(struct ipv6hdr));
613 skb_reset_network_header(new);
614 skb_copy_to_linear_data(new, hdr, sizeof(struct ipv6hdr));
616 new->protocol = htons(ETH_P_IPV6);
617 new->pkt_type = PACKET_HOST;
620 list_for_each_entry_rcu(entry, &lowpan_devices, list)
621 if (lowpan_dev_info(entry->ldev)->real_dev == new->dev) {
622 skb = skb_copy(new, GFP_ATOMIC);
628 skb->dev = entry->ldev;
629 stat = netif_rx(skb);
638 static void lowpan_fragment_timer_expired(unsigned long entry_addr)
640 struct lowpan_fragment *entry = (struct lowpan_fragment *)entry_addr;
642 pr_debug("%s: timer expired for frame with tag %d\n", __func__,
645 spin_lock(&flist_lock);
646 list_del(&entry->list);
647 spin_unlock(&flist_lock);
649 dev_kfree_skb(entry->skb);
653 static struct lowpan_fragment *
654 lowpan_alloc_new_frame(struct sk_buff *skb, u8 iphc0, u8 len, u8 tag)
656 struct lowpan_fragment *frame;
658 frame = kzalloc(sizeof(struct lowpan_fragment),
663 INIT_LIST_HEAD(&frame->list);
665 frame->length = (iphc0 & 7) | (len << 3);
668 /* allocate buffer for frame assembling */
669 frame->skb = alloc_skb(frame->length +
670 sizeof(struct ipv6hdr), GFP_ATOMIC);
675 frame->skb->priority = skb->priority;
676 frame->skb->dev = skb->dev;
678 /* reserve headroom for uncompressed ipv6 header */
679 skb_reserve(frame->skb, sizeof(struct ipv6hdr));
680 skb_put(frame->skb, frame->length);
682 init_timer(&frame->timer);
683 /* time out is the same as for ipv6 - 60 sec */
684 frame->timer.expires = jiffies + LOWPAN_FRAG_TIMEOUT;
685 frame->timer.data = (unsigned long)frame;
686 frame->timer.function = lowpan_fragment_timer_expired;
688 add_timer(&frame->timer);
690 list_add_tail(&frame->list, &lowpan_fragments);
701 lowpan_process_data(struct sk_buff *skb)
704 u8 tmp, iphc0, iphc1, num_context = 0;
708 lowpan_raw_dump_table(__func__, "raw skb data dump", skb->data,
710 /* at least two bytes will be used for the encoding */
713 iphc0 = lowpan_fetch_skb_u8(skb);
715 /* fragments assembling */
716 switch (iphc0 & LOWPAN_DISPATCH_MASK) {
717 case LOWPAN_DISPATCH_FRAG1:
718 case LOWPAN_DISPATCH_FRAGN:
720 struct lowpan_fragment *frame;
725 len = lowpan_fetch_skb_u8(skb); /* frame length */
726 tag = lowpan_fetch_skb_u16(skb);
729 * check if frame assembling with the same tag is
730 * already in progress
732 spin_lock(&flist_lock);
734 list_for_each_entry(frame, &lowpan_fragments, list)
735 if (frame->tag == tag) {
740 /* alloc new frame structure */
742 frame = lowpan_alloc_new_frame(skb, iphc0, len, tag);
744 goto unlock_and_drop;
747 if ((iphc0 & LOWPAN_DISPATCH_MASK) == LOWPAN_DISPATCH_FRAG1)
748 goto unlock_and_drop;
750 offset = lowpan_fetch_skb_u8(skb); /* fetch offset */
752 /* if payload fits buffer, copy it */
753 if (likely((offset * 8 + skb->len) <= frame->length))
754 skb_copy_to_linear_data_offset(frame->skb, offset * 8,
755 skb->data, skb->len);
757 goto unlock_and_drop;
759 frame->bytes_rcv += skb->len;
761 /* frame assembling complete */
762 if ((frame->bytes_rcv == frame->length) &&
763 frame->timer.expires > jiffies) {
764 /* if timer haven't expired - first of all delete it */
765 del_timer(&frame->timer);
766 list_del(&frame->list);
767 spin_unlock(&flist_lock);
772 iphc0 = lowpan_fetch_skb_u8(skb);
775 spin_unlock(&flist_lock);
777 return kfree_skb(skb), 0;
783 iphc1 = lowpan_fetch_skb_u8(skb);
785 _saddr = mac_cb(skb)->sa.hwaddr;
786 _daddr = mac_cb(skb)->da.hwaddr;
788 pr_debug("(%s): iphc0 = %02x, iphc1 = %02x\n", __func__, iphc0, iphc1);
790 /* another if the CID flag is set */
791 if (iphc1 & LOWPAN_IPHC_CID) {
792 pr_debug("(%s): CID flag is set, increase header with one\n",
796 num_context = lowpan_fetch_skb_u8(skb);
801 /* Traffic Class and Flow Label */
802 switch ((iphc0 & LOWPAN_IPHC_TF) >> 3) {
804 * Traffic Class and FLow Label carried in-line
805 * ECN + DSCP + 4-bit Pad + Flow Label (4 bytes)
810 tmp = lowpan_fetch_skb_u8(skb);
811 memcpy(&hdr.flow_lbl, &skb->data[0], 3);
813 hdr.priority = ((tmp >> 2) & 0x0f);
814 hdr.flow_lbl[0] = ((tmp >> 2) & 0x30) | (tmp << 6) |
815 (hdr.flow_lbl[0] & 0x0f);
818 * Traffic class carried in-line
819 * ECN + DSCP (1 byte), Flow Label is elided
824 tmp = lowpan_fetch_skb_u8(skb);
825 hdr.priority = ((tmp >> 2) & 0x0f);
826 hdr.flow_lbl[0] = ((tmp << 6) & 0xC0) | ((tmp >> 2) & 0x30);
831 * Flow Label carried in-line
832 * ECN + 2-bit Pad + Flow Label (3 bytes), DSCP is elided
837 tmp = lowpan_fetch_skb_u8(skb);
838 hdr.flow_lbl[0] = (skb->data[0] & 0x0F) | ((tmp >> 2) & 0x30);
839 memcpy(&hdr.flow_lbl[1], &skb->data[0], 2);
842 /* Traffic Class and Flow Label are elided */
854 if ((iphc0 & LOWPAN_IPHC_NH_C) == 0) {
855 /* Next header is carried inline */
858 hdr.nexthdr = lowpan_fetch_skb_u8(skb);
859 pr_debug("(%s): NH flag is set, next header is carried "
860 "inline: %02x\n", __func__, hdr.nexthdr);
864 if ((iphc0 & 0x03) != LOWPAN_IPHC_TTL_I)
865 hdr.hop_limit = lowpan_ttl_values[iphc0 & 0x03];
869 hdr.hop_limit = lowpan_fetch_skb_u8(skb);
872 /* Extract SAM to the tmp variable */
873 tmp = ((iphc1 & LOWPAN_IPHC_SAM) >> LOWPAN_IPHC_SAM_BIT) & 0x03;
875 /* Source address uncompression */
876 pr_debug("(%s): source address stateless compression\n", __func__);
877 err = lowpan_uncompress_addr(skb, &hdr.saddr, lowpan_llprefix,
878 lowpan_unc_llconf[tmp], skb->data);
882 /* Extract DAM to the tmp variable */
883 tmp = ((iphc1 & LOWPAN_IPHC_DAM_11) >> LOWPAN_IPHC_DAM_BIT) & 0x03;
885 /* check for Multicast Compression */
886 if (iphc1 & LOWPAN_IPHC_M) {
887 if (iphc1 & LOWPAN_IPHC_DAC) {
888 pr_debug("(%s): destination address context-based "
889 "multicast compression\n", __func__);
890 /* TODO: implement this */
892 u8 prefix[] = {0xff, 0x02};
894 pr_debug("(%s): destination address non-context-based"
895 " multicast compression\n", __func__);
896 if (0 < tmp && tmp < 3) {
900 prefix[1] = lowpan_fetch_skb_u8(skb);
903 err = lowpan_uncompress_addr(skb, &hdr.daddr, prefix,
904 lowpan_unc_mxconf[tmp], NULL);
909 pr_debug("(%s): destination address stateless compression\n",
911 err = lowpan_uncompress_addr(skb, &hdr.daddr, lowpan_llprefix,
912 lowpan_unc_llconf[tmp], skb->data);
917 /* UDP data uncompression */
918 if (iphc0 & LOWPAN_IPHC_NH_C)
919 if (lowpan_uncompress_udp_header(skb))
922 /* Not fragmented package */
923 hdr.payload_len = htons(skb->len);
925 pr_debug("(%s): skb headroom size = %d, data length = %d\n", __func__,
926 skb_headroom(skb), skb->len);
928 pr_debug("(%s): IPv6 header dump:\n\tversion = %d\n\tlength = %d\n\t"
929 "nexthdr = 0x%02x\n\thop_lim = %d\n", __func__, hdr.version,
930 ntohs(hdr.payload_len), hdr.nexthdr, hdr.hop_limit);
932 lowpan_raw_dump_table(__func__, "raw header dump", (u8 *)&hdr,
934 return lowpan_skb_deliver(skb, &hdr);
937 spin_unlock(&flist_lock);
943 static int lowpan_get_mac_header_length(struct sk_buff *skb)
946 * Currently long addressing mode is supported only, so the overall
948 * FC SeqNum DPAN DA SA Sec
949 * 2 + 1 + 2 + 8 + 8 + 0 = 21
955 lowpan_fragment_xmit(struct sk_buff *skb, u8 *head,
956 int mlen, int plen, int offset)
958 struct sk_buff *frag;
961 /* if payload length is zero, therefore it's a first fragment */
962 hlen = (plen == 0 ? LOWPAN_FRAG1_HEAD_SIZE : LOWPAN_FRAGN_HEAD_SIZE);
964 lowpan_raw_dump_inline(__func__, "6lowpan fragment header", head, hlen);
966 frag = dev_alloc_skb(hlen + mlen + plen + IEEE802154_MFR_SIZE);
970 frag->priority = skb->priority;
971 frag->dev = skb->dev;
973 /* copy header, MFR and payload */
974 memcpy(skb_put(frag, mlen), skb->data, mlen);
975 memcpy(skb_put(frag, hlen), head, hlen);
978 skb_copy_from_linear_data_offset(skb, offset + mlen,
979 skb_put(frag, plen), plen);
981 lowpan_raw_dump_table(__func__, " raw fragment dump", frag->data,
984 ret = dev_queue_xmit(frag);
990 lowpan_skb_fragmentation(struct sk_buff *skb)
992 int err, header_length, payload_length, tag, offset = 0;
995 header_length = lowpan_get_mac_header_length(skb);
996 payload_length = skb->len - header_length;
997 tag = fragment_tag++;
999 /* first fragment header */
1000 head[0] = LOWPAN_DISPATCH_FRAG1 | (payload_length & 0x7);
1001 head[1] = (payload_length >> 3) & 0xff;
1002 head[2] = tag & 0xff;
1005 err = lowpan_fragment_xmit(skb, head, header_length, 0, 0);
1007 /* next fragment header */
1008 head[0] &= ~LOWPAN_DISPATCH_FRAG1;
1009 head[0] |= LOWPAN_DISPATCH_FRAGN;
1011 while ((payload_length - offset > 0) && (err >= 0)) {
1012 int len = LOWPAN_FRAG_SIZE;
1014 head[4] = offset / 8;
1016 if (payload_length - offset < len)
1017 len = payload_length - offset;
1019 err = lowpan_fragment_xmit(skb, head, header_length,
1027 static netdev_tx_t lowpan_xmit(struct sk_buff *skb, struct net_device *dev)
1031 pr_debug("(%s): package xmit\n", __func__);
1033 skb->dev = lowpan_dev_info(dev)->real_dev;
1034 if (skb->dev == NULL) {
1035 pr_debug("(%s) ERROR: no real wpan device found\n", __func__);
1039 if (skb->len <= IEEE802154_MTU) {
1040 err = dev_queue_xmit(skb);
1044 pr_debug("(%s): frame is too big, fragmentation is needed\n",
1046 err = lowpan_skb_fragmentation(skb);
1051 pr_debug("(%s): ERROR: xmit failed\n", __func__);
1053 return (err < 0 ? NETDEV_TX_BUSY : NETDEV_TX_OK);
1056 static void lowpan_dev_free(struct net_device *dev)
1058 dev_put(lowpan_dev_info(dev)->real_dev);
1062 static struct wpan_phy *lowpan_get_phy(const struct net_device *dev)
1064 struct net_device *real_dev = lowpan_dev_info(dev)->real_dev;
1065 return ieee802154_mlme_ops(real_dev)->get_phy(real_dev);
1068 static u16 lowpan_get_pan_id(const struct net_device *dev)
1070 struct net_device *real_dev = lowpan_dev_info(dev)->real_dev;
1071 return ieee802154_mlme_ops(real_dev)->get_pan_id(real_dev);
1074 static u16 lowpan_get_short_addr(const struct net_device *dev)
1076 struct net_device *real_dev = lowpan_dev_info(dev)->real_dev;
1077 return ieee802154_mlme_ops(real_dev)->get_short_addr(real_dev);
1080 static struct header_ops lowpan_header_ops = {
1081 .create = lowpan_header_create,
1084 static const struct net_device_ops lowpan_netdev_ops = {
1085 .ndo_start_xmit = lowpan_xmit,
1086 .ndo_set_mac_address = eth_mac_addr,
1089 static struct ieee802154_mlme_ops lowpan_mlme = {
1090 .get_pan_id = lowpan_get_pan_id,
1091 .get_phy = lowpan_get_phy,
1092 .get_short_addr = lowpan_get_short_addr,
1095 static void lowpan_setup(struct net_device *dev)
1097 pr_debug("(%s)\n", __func__);
1099 dev->addr_len = IEEE802154_ADDR_LEN;
1100 memset(dev->broadcast, 0xff, IEEE802154_ADDR_LEN);
1101 dev->type = ARPHRD_IEEE802154;
1102 /* Frame Control + Sequence Number + Address fields + Security Header */
1103 dev->hard_header_len = 2 + 1 + 20 + 14;
1104 dev->needed_tailroom = 2; /* FCS */
1106 dev->tx_queue_len = 0;
1107 dev->flags = IFF_BROADCAST | IFF_MULTICAST;
1108 dev->watchdog_timeo = 0;
1110 dev->netdev_ops = &lowpan_netdev_ops;
1111 dev->header_ops = &lowpan_header_ops;
1112 dev->ml_priv = &lowpan_mlme;
1113 dev->destructor = lowpan_dev_free;
1116 static int lowpan_validate(struct nlattr *tb[], struct nlattr *data[])
1118 pr_debug("(%s)\n", __func__);
1120 if (tb[IFLA_ADDRESS]) {
1121 if (nla_len(tb[IFLA_ADDRESS]) != IEEE802154_ADDR_LEN)
1127 static int lowpan_rcv(struct sk_buff *skb, struct net_device *dev,
1128 struct packet_type *pt, struct net_device *orig_dev)
1130 if (!netif_running(dev))
1133 if (dev->type != ARPHRD_IEEE802154)
1136 /* check that it's our buffer */
1137 switch (skb->data[0] & 0xe0) {
1138 case LOWPAN_DISPATCH_IPHC: /* ipv6 datagram */
1139 case LOWPAN_DISPATCH_FRAG1: /* first fragment header */
1140 case LOWPAN_DISPATCH_FRAGN: /* next fragments headers */
1141 lowpan_process_data(skb);
1147 return NET_RX_SUCCESS;
1154 static int lowpan_newlink(struct net *src_net, struct net_device *dev,
1155 struct nlattr *tb[], struct nlattr *data[])
1157 struct net_device *real_dev;
1158 struct lowpan_dev_record *entry;
1160 pr_debug("(%s)\n", __func__);
1164 /* find and hold real wpan device */
1165 real_dev = dev_get_by_index(src_net, nla_get_u32(tb[IFLA_LINK]));
1169 lowpan_dev_info(dev)->real_dev = real_dev;
1170 mutex_init(&lowpan_dev_info(dev)->dev_list_mtx);
1172 entry = kzalloc(sizeof(struct lowpan_dev_record), GFP_KERNEL);
1175 lowpan_dev_info(dev)->real_dev = NULL;
1181 mutex_lock(&lowpan_dev_info(dev)->dev_list_mtx);
1182 INIT_LIST_HEAD(&entry->list);
1183 list_add_tail(&entry->list, &lowpan_devices);
1184 mutex_unlock(&lowpan_dev_info(dev)->dev_list_mtx);
1186 spin_lock_init(&flist_lock);
1188 register_netdevice(dev);
1193 static void lowpan_dellink(struct net_device *dev, struct list_head *head)
1195 struct lowpan_dev_info *lowpan_dev = lowpan_dev_info(dev);
1196 struct net_device *real_dev = lowpan_dev->real_dev;
1197 struct lowpan_dev_record *entry, *tmp;
1198 struct lowpan_fragment *frame, *tframe;
1202 spin_lock(&flist_lock);
1203 list_for_each_entry_safe(frame, tframe, &lowpan_fragments, list) {
1204 del_timer(&frame->timer);
1205 list_del(&frame->list);
1206 dev_kfree_skb(frame->skb);
1209 spin_unlock(&flist_lock);
1211 mutex_lock(&lowpan_dev_info(dev)->dev_list_mtx);
1212 list_for_each_entry_safe(entry, tmp, &lowpan_devices, list) {
1213 if (entry->ldev == dev) {
1214 list_del(&entry->list);
1218 mutex_unlock(&lowpan_dev_info(dev)->dev_list_mtx);
1220 mutex_destroy(&lowpan_dev_info(dev)->dev_list_mtx);
1222 unregister_netdevice_queue(dev, head);
1227 static struct rtnl_link_ops lowpan_link_ops __read_mostly = {
1229 .priv_size = sizeof(struct lowpan_dev_info),
1230 .setup = lowpan_setup,
1231 .newlink = lowpan_newlink,
1232 .dellink = lowpan_dellink,
1233 .validate = lowpan_validate,
1236 static inline int __init lowpan_netlink_init(void)
1238 return rtnl_link_register(&lowpan_link_ops);
1241 static inline void __init lowpan_netlink_fini(void)
1243 rtnl_link_unregister(&lowpan_link_ops);
1246 static struct packet_type lowpan_packet_type = {
1247 .type = __constant_htons(ETH_P_IEEE802154),
1251 static int __init lowpan_init_module(void)
1255 pr_debug("(%s)\n", __func__);
1257 err = lowpan_netlink_init();
1261 dev_add_pack(&lowpan_packet_type);
1266 static void __exit lowpan_cleanup_module(void)
1268 pr_debug("(%s)\n", __func__);
1270 lowpan_netlink_fini();
1272 dev_remove_pack(&lowpan_packet_type);
1275 module_init(lowpan_init_module);
1276 module_exit(lowpan_cleanup_module);
1277 MODULE_LICENSE("GPL");
1278 MODULE_ALIAS_RTNL_LINK("lowpan");