diff options
Diffstat (limited to 'net/ieee802154/6lowpan')
| -rw-r--r-- | net/ieee802154/6lowpan/6lowpan_i.h | 48 | ||||
| -rw-r--r-- | net/ieee802154/6lowpan/Kconfig | 5 | ||||
| -rw-r--r-- | net/ieee802154/6lowpan/Makefile | 3 | ||||
| -rw-r--r-- | net/ieee802154/6lowpan/core.c | 283 | ||||
| -rw-r--r-- | net/ieee802154/6lowpan/reassembly.c | 635 | ||||
| -rw-r--r-- | net/ieee802154/6lowpan/rx.c | 331 | ||||
| -rw-r--r-- | net/ieee802154/6lowpan/tx.c | 317 |
7 files changed, 1622 insertions, 0 deletions
diff --git a/net/ieee802154/6lowpan/6lowpan_i.h b/net/ieee802154/6lowpan/6lowpan_i.h new file mode 100644 index 000000000..44a7e16bf --- /dev/null +++ b/net/ieee802154/6lowpan/6lowpan_i.h @@ -0,0 +1,48 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __IEEE802154_6LOWPAN_I_H__ +#define __IEEE802154_6LOWPAN_I_H__ + +#include <linux/list.h> + +#include <net/ieee802154_netdev.h> +#include <net/inet_frag.h> +#include <net/6lowpan.h> + +typedef unsigned __bitwise lowpan_rx_result; +#define RX_CONTINUE ((__force lowpan_rx_result) 0u) +#define RX_DROP_UNUSABLE ((__force lowpan_rx_result) 1u) +#define RX_DROP ((__force lowpan_rx_result) 2u) +#define RX_QUEUED ((__force lowpan_rx_result) 3u) + +#define LOWPAN_DISPATCH_FRAG1 0xc0 +#define LOWPAN_DISPATCH_FRAGN 0xe0 + +struct frag_lowpan_compare_key { + u16 tag; + u16 d_size; + struct ieee802154_addr src; + struct ieee802154_addr dst; +}; + +/* Equivalent of ipv4 struct ipq + */ +struct lowpan_frag_queue { + struct inet_frag_queue q; +}; + +int lowpan_frag_rcv(struct sk_buff *skb, const u8 frag_type); +void lowpan_net_frag_exit(void); +int lowpan_net_frag_init(void); + +void lowpan_rx_init(void); +void lowpan_rx_exit(void); + +int lowpan_header_create(struct sk_buff *skb, struct net_device *dev, + unsigned short type, const void *_daddr, + const void *_saddr, unsigned int len); +netdev_tx_t lowpan_xmit(struct sk_buff *skb, struct net_device *dev); + +int lowpan_iphc_decompress(struct sk_buff *skb); +lowpan_rx_result lowpan_rx_h_ipv6(struct sk_buff *skb); + +#endif /* __IEEE802154_6LOWPAN_I_H__ */ diff --git a/net/ieee802154/6lowpan/Kconfig b/net/ieee802154/6lowpan/Kconfig new file mode 100644 index 000000000..d24f985b0 --- /dev/null +++ b/net/ieee802154/6lowpan/Kconfig @@ -0,0 +1,5 @@ +config IEEE802154_6LOWPAN + tristate "6lowpan support over IEEE 802.15.4" + depends on 6LOWPAN + ---help--- + IPv6 compression over IEEE 802.15.4. diff --git a/net/ieee802154/6lowpan/Makefile b/net/ieee802154/6lowpan/Makefile new file mode 100644 index 000000000..6bfb270a8 --- /dev/null +++ b/net/ieee802154/6lowpan/Makefile @@ -0,0 +1,3 @@ +obj-$(CONFIG_IEEE802154_6LOWPAN) += ieee802154_6lowpan.o + +ieee802154_6lowpan-y := core.o rx.o reassembly.o tx.o diff --git a/net/ieee802154/6lowpan/core.c b/net/ieee802154/6lowpan/core.c new file mode 100644 index 000000000..3297e7fa9 --- /dev/null +++ b/net/ieee802154/6lowpan/core.c @@ -0,0 +1,283 @@ +/* Copyright 2011, Siemens AG + * written by Alexander Smirnov <alex.bluesman.smirnov@gmail.com> + */ + +/* Based on patches from Jon Smirl <jonsmirl@gmail.com> + * Copyright (c) 2011 Jon Smirl <jonsmirl@gmail.com> + * + * 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. + */ + +/* Jon's code is based on 6lowpan implementation for Contiki which is: + * Copyright (c) 2008, Swedish Institute of Computer Science. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of the Institute nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include <linux/module.h> +#include <linux/netdevice.h> +#include <linux/ieee802154.h> + +#include <net/ipv6.h> + +#include "6lowpan_i.h" + +static int open_count; + +static const struct header_ops lowpan_header_ops = { + .create = lowpan_header_create, +}; + +static int lowpan_dev_init(struct net_device *ldev) +{ + netdev_lockdep_set_classes(ldev); + + return 0; +} + +static int lowpan_open(struct net_device *dev) +{ + if (!open_count) + lowpan_rx_init(); + open_count++; + return 0; +} + +static int lowpan_stop(struct net_device *dev) +{ + open_count--; + if (!open_count) + lowpan_rx_exit(); + return 0; +} + +static int lowpan_neigh_construct(struct net_device *dev, struct neighbour *n) +{ + struct lowpan_802154_neigh *neigh = lowpan_802154_neigh(neighbour_priv(n)); + + /* default no short_addr is available for a neighbour */ + neigh->short_addr = cpu_to_le16(IEEE802154_ADDR_SHORT_UNSPEC); + return 0; +} + +static int lowpan_get_iflink(const struct net_device *dev) +{ + return lowpan_802154_dev(dev)->wdev->ifindex; +} + +static const struct net_device_ops lowpan_netdev_ops = { + .ndo_init = lowpan_dev_init, + .ndo_start_xmit = lowpan_xmit, + .ndo_open = lowpan_open, + .ndo_stop = lowpan_stop, + .ndo_neigh_construct = lowpan_neigh_construct, + .ndo_get_iflink = lowpan_get_iflink, +}; + +static void lowpan_setup(struct net_device *ldev) +{ + memset(ldev->broadcast, 0xff, IEEE802154_ADDR_LEN); + /* We need an ipv6hdr as minimum len when calling xmit */ + ldev->hard_header_len = sizeof(struct ipv6hdr); + ldev->flags = IFF_BROADCAST | IFF_MULTICAST; + ldev->priv_flags |= IFF_NO_QUEUE; + + ldev->netdev_ops = &lowpan_netdev_ops; + ldev->header_ops = &lowpan_header_ops; + ldev->needs_free_netdev = true; + ldev->features |= NETIF_F_NETNS_LOCAL; +} + +static int lowpan_validate(struct nlattr *tb[], struct nlattr *data[], + struct netlink_ext_ack *extack) +{ + if (tb[IFLA_ADDRESS]) { + if (nla_len(tb[IFLA_ADDRESS]) != IEEE802154_ADDR_LEN) + return -EINVAL; + } + return 0; +} + +static int lowpan_newlink(struct net *src_net, struct net_device *ldev, + struct nlattr *tb[], struct nlattr *data[], + struct netlink_ext_ack *extack) +{ + struct net_device *wdev; + int ret; + + ASSERT_RTNL(); + + pr_debug("adding new link\n"); + + if (!tb[IFLA_LINK]) + return -EINVAL; + /* find and hold wpan device */ + wdev = dev_get_by_index(dev_net(ldev), nla_get_u32(tb[IFLA_LINK])); + if (!wdev) + return -ENODEV; + if (wdev->type != ARPHRD_IEEE802154) { + dev_put(wdev); + return -EINVAL; + } + + if (wdev->ieee802154_ptr->lowpan_dev) { + dev_put(wdev); + return -EBUSY; + } + + lowpan_802154_dev(ldev)->wdev = wdev; + /* Set the lowpan hardware address to the wpan hardware address. */ + memcpy(ldev->dev_addr, wdev->dev_addr, IEEE802154_ADDR_LEN); + /* We need headroom for possible wpan_dev_hard_header call and tailroom + * for encryption/fcs handling. The lowpan interface will replace + * the IPv6 header with 6LoWPAN header. At worst case the 6LoWPAN + * header has LOWPAN_IPHC_MAX_HEADER_LEN more bytes than the IPv6 + * header. + */ + ldev->needed_headroom = LOWPAN_IPHC_MAX_HEADER_LEN + + wdev->needed_headroom; + ldev->needed_tailroom = wdev->needed_tailroom; + + ldev->neigh_priv_len = sizeof(struct lowpan_802154_neigh); + + ret = lowpan_register_netdevice(ldev, LOWPAN_LLTYPE_IEEE802154); + if (ret < 0) { + dev_put(wdev); + return ret; + } + + wdev->ieee802154_ptr->lowpan_dev = ldev; + return 0; +} + +static void lowpan_dellink(struct net_device *ldev, struct list_head *head) +{ + struct net_device *wdev = lowpan_802154_dev(ldev)->wdev; + + ASSERT_RTNL(); + + wdev->ieee802154_ptr->lowpan_dev = NULL; + lowpan_unregister_netdevice(ldev); + dev_put(wdev); +} + +static struct rtnl_link_ops lowpan_link_ops __read_mostly = { + .kind = "lowpan", + .priv_size = LOWPAN_PRIV_SIZE(sizeof(struct lowpan_802154_dev)), + .setup = lowpan_setup, + .newlink = lowpan_newlink, + .dellink = lowpan_dellink, + .validate = lowpan_validate, +}; + +static inline int __init lowpan_netlink_init(void) +{ + return rtnl_link_register(&lowpan_link_ops); +} + +static inline void lowpan_netlink_fini(void) +{ + rtnl_link_unregister(&lowpan_link_ops); +} + +static int lowpan_device_event(struct notifier_block *unused, + unsigned long event, void *ptr) +{ + struct net_device *ndev = netdev_notifier_info_to_dev(ptr); + struct wpan_dev *wpan_dev; + + if (ndev->type != ARPHRD_IEEE802154) + return NOTIFY_DONE; + wpan_dev = ndev->ieee802154_ptr; + if (!wpan_dev) + return NOTIFY_DONE; + + switch (event) { + case NETDEV_UNREGISTER: + /* Check if wpan interface is unregistered that we + * also delete possible lowpan interfaces which belongs + * to the wpan interface. + */ + if (wpan_dev->lowpan_dev) + lowpan_dellink(wpan_dev->lowpan_dev, NULL); + break; + default: + return NOTIFY_DONE; + } + + return NOTIFY_OK; +} + +static struct notifier_block lowpan_dev_notifier = { + .notifier_call = lowpan_device_event, +}; + +static int __init lowpan_init_module(void) +{ + int err = 0; + + err = lowpan_net_frag_init(); + if (err < 0) + goto out; + + err = lowpan_netlink_init(); + if (err < 0) + goto out_frag; + + err = register_netdevice_notifier(&lowpan_dev_notifier); + if (err < 0) + goto out_pack; + + return 0; + +out_pack: + lowpan_netlink_fini(); +out_frag: + lowpan_net_frag_exit(); +out: + return err; +} + +static void __exit lowpan_cleanup_module(void) +{ + lowpan_netlink_fini(); + + lowpan_net_frag_exit(); + + unregister_netdevice_notifier(&lowpan_dev_notifier); +} + +module_init(lowpan_init_module); +module_exit(lowpan_cleanup_module); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_RTNL_LINK("lowpan"); diff --git a/net/ieee802154/6lowpan/reassembly.c b/net/ieee802154/6lowpan/reassembly.c new file mode 100644 index 000000000..f3074249c --- /dev/null +++ b/net/ieee802154/6lowpan/reassembly.c @@ -0,0 +1,635 @@ +/* 6LoWPAN fragment reassembly + * + * + * Authors: + * Alexander Aring <aar@pengutronix.de> + * + * Based on: net/ipv6/reassembly.c + * + * 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. + */ + +#define pr_fmt(fmt) "6LoWPAN: " fmt + +#include <linux/net.h> +#include <linux/list.h> +#include <linux/netdevice.h> +#include <linux/random.h> +#include <linux/jhash.h> +#include <linux/skbuff.h> +#include <linux/slab.h> +#include <linux/export.h> + +#include <net/ieee802154_netdev.h> +#include <net/6lowpan.h> +#include <net/ipv6_frag.h> +#include <net/inet_frag.h> + +#include "6lowpan_i.h" + +static const char lowpan_frags_cache_name[] = "lowpan-frags"; + +static struct inet_frags lowpan_frags; + +static int lowpan_frag_reasm(struct lowpan_frag_queue *fq, + struct sk_buff *prev, struct net_device *ldev); + +static void lowpan_frag_init(struct inet_frag_queue *q, const void *a) +{ + const struct frag_lowpan_compare_key *key = a; + + BUILD_BUG_ON(sizeof(*key) > sizeof(q->key)); + memcpy(&q->key, key, sizeof(*key)); +} + +static void lowpan_frag_expire(struct timer_list *t) +{ + struct inet_frag_queue *frag = from_timer(frag, t, timer); + struct frag_queue *fq; + + fq = container_of(frag, struct frag_queue, q); + + spin_lock(&fq->q.lock); + + if (fq->q.flags & INET_FRAG_COMPLETE) + goto out; + + inet_frag_kill(&fq->q); +out: + spin_unlock(&fq->q.lock); + inet_frag_put(&fq->q); +} + +static inline struct lowpan_frag_queue * +fq_find(struct net *net, const struct lowpan_802154_cb *cb, + const struct ieee802154_addr *src, + const struct ieee802154_addr *dst) +{ + struct netns_ieee802154_lowpan *ieee802154_lowpan = + net_ieee802154_lowpan(net); + struct frag_lowpan_compare_key key = {}; + struct inet_frag_queue *q; + + key.tag = cb->d_tag; + key.d_size = cb->d_size; + key.src = *src; + key.dst = *dst; + + q = inet_frag_find(&ieee802154_lowpan->frags, &key); + if (!q) + return NULL; + + return container_of(q, struct lowpan_frag_queue, q); +} + +static int lowpan_frag_queue(struct lowpan_frag_queue *fq, + struct sk_buff *skb, u8 frag_type) +{ + struct sk_buff *prev, *next; + struct net_device *ldev; + int end, offset; + + if (fq->q.flags & INET_FRAG_COMPLETE) + goto err; + + offset = lowpan_802154_cb(skb)->d_offset << 3; + end = lowpan_802154_cb(skb)->d_size; + + /* Is this the final fragment? */ + if (offset + skb->len == end) { + /* If we already have some bits beyond end + * or have different end, the segment is corrupted. + */ + if (end < fq->q.len || + ((fq->q.flags & INET_FRAG_LAST_IN) && end != fq->q.len)) + goto err; + fq->q.flags |= INET_FRAG_LAST_IN; + fq->q.len = end; + } else { + if (end > fq->q.len) { + /* Some bits beyond end -> corruption. */ + if (fq->q.flags & INET_FRAG_LAST_IN) + goto err; + fq->q.len = end; + } + } + + /* Find out which fragments are in front and at the back of us + * in the chain of fragments so far. We must know where to put + * this fragment, right? + */ + prev = fq->q.fragments_tail; + if (!prev || + lowpan_802154_cb(prev)->d_offset < + lowpan_802154_cb(skb)->d_offset) { + next = NULL; + goto found; + } + prev = NULL; + for (next = fq->q.fragments; next != NULL; next = next->next) { + if (lowpan_802154_cb(next)->d_offset >= + lowpan_802154_cb(skb)->d_offset) + break; /* bingo! */ + prev = next; + } + +found: + /* Insert this fragment in the chain of fragments. */ + skb->next = next; + if (!next) + fq->q.fragments_tail = skb; + if (prev) + prev->next = skb; + else + fq->q.fragments = skb; + + ldev = skb->dev; + if (ldev) + skb->dev = NULL; + + fq->q.stamp = skb->tstamp; + if (frag_type == LOWPAN_DISPATCH_FRAG1) + fq->q.flags |= INET_FRAG_FIRST_IN; + + fq->q.meat += skb->len; + add_frag_mem_limit(fq->q.net, skb->truesize); + + if (fq->q.flags == (INET_FRAG_FIRST_IN | INET_FRAG_LAST_IN) && + fq->q.meat == fq->q.len) { + int res; + unsigned long orefdst = skb->_skb_refdst; + + skb->_skb_refdst = 0UL; + res = lowpan_frag_reasm(fq, prev, ldev); + skb->_skb_refdst = orefdst; + return res; + } + + return -1; +err: + kfree_skb(skb); + return -1; +} + +/* Check if this packet is complete. + * Returns NULL on failure by any reason, and pointer + * to current nexthdr field in reassembled frame. + * + * It is called with locked fq, and caller must check that + * queue is eligible for reassembly i.e. it is not COMPLETE, + * the last and the first frames arrived and all the bits are here. + */ +static int lowpan_frag_reasm(struct lowpan_frag_queue *fq, struct sk_buff *prev, + struct net_device *ldev) +{ + struct sk_buff *fp, *head = fq->q.fragments; + int sum_truesize; + + inet_frag_kill(&fq->q); + + /* Make the one we just received the head. */ + if (prev) { + head = prev->next; + fp = skb_clone(head, GFP_ATOMIC); + + if (!fp) + goto out_oom; + + fp->next = head->next; + if (!fp->next) + fq->q.fragments_tail = fp; + prev->next = fp; + + skb_morph(head, fq->q.fragments); + head->next = fq->q.fragments->next; + + consume_skb(fq->q.fragments); + fq->q.fragments = head; + } + + /* Head of list must not be cloned. */ + if (skb_unclone(head, GFP_ATOMIC)) + goto out_oom; + + /* If the first fragment is fragmented itself, we split + * it to two chunks: the first with data and paged part + * and the second, holding only fragments. + */ + if (skb_has_frag_list(head)) { + struct sk_buff *clone; + int i, plen = 0; + + clone = alloc_skb(0, GFP_ATOMIC); + if (!clone) + goto out_oom; + clone->next = head->next; + head->next = clone; + skb_shinfo(clone)->frag_list = skb_shinfo(head)->frag_list; + skb_frag_list_init(head); + for (i = 0; i < skb_shinfo(head)->nr_frags; i++) + plen += skb_frag_size(&skb_shinfo(head)->frags[i]); + clone->len = head->data_len - plen; + clone->data_len = clone->len; + head->data_len -= clone->len; + head->len -= clone->len; + add_frag_mem_limit(fq->q.net, clone->truesize); + } + + WARN_ON(head == NULL); + + sum_truesize = head->truesize; + for (fp = head->next; fp;) { + bool headstolen; + int delta; + struct sk_buff *next = fp->next; + + sum_truesize += fp->truesize; + if (skb_try_coalesce(head, fp, &headstolen, &delta)) { + kfree_skb_partial(fp, headstolen); + } else { + if (!skb_shinfo(head)->frag_list) + skb_shinfo(head)->frag_list = fp; + head->data_len += fp->len; + head->len += fp->len; + head->truesize += fp->truesize; + } + fp = next; + } + sub_frag_mem_limit(fq->q.net, sum_truesize); + + head->next = NULL; + head->dev = ldev; + head->tstamp = fq->q.stamp; + + fq->q.fragments = NULL; + fq->q.fragments_tail = NULL; + + return 1; +out_oom: + net_dbg_ratelimited("lowpan_frag_reasm: no memory for reassembly\n"); + return -1; +} + +static int lowpan_frag_rx_handlers_result(struct sk_buff *skb, + lowpan_rx_result res) +{ + switch (res) { + case RX_QUEUED: + return NET_RX_SUCCESS; + case RX_CONTINUE: + /* nobody cared about this packet */ + net_warn_ratelimited("%s: received unknown dispatch\n", + __func__); + + /* fall-through */ + default: + /* all others failure */ + return NET_RX_DROP; + } +} + +static lowpan_rx_result lowpan_frag_rx_h_iphc(struct sk_buff *skb) +{ + int ret; + + if (!lowpan_is_iphc(*skb_network_header(skb))) + return RX_CONTINUE; + + ret = lowpan_iphc_decompress(skb); + if (ret < 0) + return RX_DROP; + + return RX_QUEUED; +} + +static int lowpan_invoke_frag_rx_handlers(struct sk_buff *skb) +{ + lowpan_rx_result res; + +#define CALL_RXH(rxh) \ + do { \ + res = rxh(skb); \ + if (res != RX_CONTINUE) \ + goto rxh_next; \ + } while (0) + + /* likely at first */ + CALL_RXH(lowpan_frag_rx_h_iphc); + CALL_RXH(lowpan_rx_h_ipv6); + +rxh_next: + return lowpan_frag_rx_handlers_result(skb, res); +#undef CALL_RXH +} + +#define LOWPAN_FRAG_DGRAM_SIZE_HIGH_MASK 0x07 +#define LOWPAN_FRAG_DGRAM_SIZE_HIGH_SHIFT 8 + +static int lowpan_get_cb(struct sk_buff *skb, u8 frag_type, + struct lowpan_802154_cb *cb) +{ + bool fail; + u8 high = 0, low = 0; + __be16 d_tag = 0; + + fail = lowpan_fetch_skb(skb, &high, 1); + fail |= lowpan_fetch_skb(skb, &low, 1); + /* remove the dispatch value and use first three bits as high value + * for the datagram size + */ + cb->d_size = (high & LOWPAN_FRAG_DGRAM_SIZE_HIGH_MASK) << + LOWPAN_FRAG_DGRAM_SIZE_HIGH_SHIFT | low; + fail |= lowpan_fetch_skb(skb, &d_tag, 2); + cb->d_tag = ntohs(d_tag); + + if (frag_type == LOWPAN_DISPATCH_FRAGN) { + fail |= lowpan_fetch_skb(skb, &cb->d_offset, 1); + } else { + skb_reset_network_header(skb); + cb->d_offset = 0; + /* check if datagram_size has ipv6hdr on FRAG1 */ + fail |= cb->d_size < sizeof(struct ipv6hdr); + /* check if we can dereference the dispatch value */ + fail |= !skb->len; + } + + if (unlikely(fail)) + return -EIO; + + return 0; +} + +int lowpan_frag_rcv(struct sk_buff *skb, u8 frag_type) +{ + struct lowpan_frag_queue *fq; + struct net *net = dev_net(skb->dev); + struct lowpan_802154_cb *cb = lowpan_802154_cb(skb); + struct ieee802154_hdr hdr = {}; + int err; + + if (ieee802154_hdr_peek_addrs(skb, &hdr) < 0) + goto err; + + err = lowpan_get_cb(skb, frag_type, cb); + if (err < 0) + goto err; + + if (frag_type == LOWPAN_DISPATCH_FRAG1) { + err = lowpan_invoke_frag_rx_handlers(skb); + if (err == NET_RX_DROP) + goto err; + } + + if (cb->d_size > IPV6_MIN_MTU) { + net_warn_ratelimited("lowpan_frag_rcv: datagram size exceeds MTU\n"); + goto err; + } + + fq = fq_find(net, cb, &hdr.source, &hdr.dest); + if (fq != NULL) { + int ret; + + spin_lock(&fq->q.lock); + ret = lowpan_frag_queue(fq, skb, frag_type); + spin_unlock(&fq->q.lock); + + inet_frag_put(&fq->q); + return ret; + } + +err: + kfree_skb(skb); + return -1; +} + +#ifdef CONFIG_SYSCTL + +static struct ctl_table lowpan_frags_ns_ctl_table[] = { + { + .procname = "6lowpanfrag_high_thresh", + .data = &init_net.ieee802154_lowpan.frags.high_thresh, + .maxlen = sizeof(unsigned long), + .mode = 0644, + .proc_handler = proc_doulongvec_minmax, + .extra1 = &init_net.ieee802154_lowpan.frags.low_thresh + }, + { + .procname = "6lowpanfrag_low_thresh", + .data = &init_net.ieee802154_lowpan.frags.low_thresh, + .maxlen = sizeof(unsigned long), + .mode = 0644, + .proc_handler = proc_doulongvec_minmax, + .extra2 = &init_net.ieee802154_lowpan.frags.high_thresh + }, + { + .procname = "6lowpanfrag_time", + .data = &init_net.ieee802154_lowpan.frags.timeout, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_jiffies, + }, + { } +}; + +/* secret interval has been deprecated */ +static int lowpan_frags_secret_interval_unused; +static struct ctl_table lowpan_frags_ctl_table[] = { + { + .procname = "6lowpanfrag_secret_interval", + .data = &lowpan_frags_secret_interval_unused, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_jiffies, + }, + { } +}; + +static int __net_init lowpan_frags_ns_sysctl_register(struct net *net) +{ + struct ctl_table *table; + struct ctl_table_header *hdr; + struct netns_ieee802154_lowpan *ieee802154_lowpan = + net_ieee802154_lowpan(net); + + table = lowpan_frags_ns_ctl_table; + if (!net_eq(net, &init_net)) { + table = kmemdup(table, sizeof(lowpan_frags_ns_ctl_table), + GFP_KERNEL); + if (table == NULL) + goto err_alloc; + + table[0].data = &ieee802154_lowpan->frags.high_thresh; + table[0].extra1 = &ieee802154_lowpan->frags.low_thresh; + table[0].extra2 = &init_net.ieee802154_lowpan.frags.high_thresh; + table[1].data = &ieee802154_lowpan->frags.low_thresh; + table[1].extra2 = &ieee802154_lowpan->frags.high_thresh; + table[2].data = &ieee802154_lowpan->frags.timeout; + + /* Don't export sysctls to unprivileged users */ + if (net->user_ns != &init_user_ns) + table[0].procname = NULL; + } + + hdr = register_net_sysctl(net, "net/ieee802154/6lowpan", table); + if (hdr == NULL) + goto err_reg; + + ieee802154_lowpan->sysctl.frags_hdr = hdr; + return 0; + +err_reg: + if (!net_eq(net, &init_net)) + kfree(table); +err_alloc: + return -ENOMEM; +} + +static void __net_exit lowpan_frags_ns_sysctl_unregister(struct net *net) +{ + struct ctl_table *table; + struct netns_ieee802154_lowpan *ieee802154_lowpan = + net_ieee802154_lowpan(net); + + table = ieee802154_lowpan->sysctl.frags_hdr->ctl_table_arg; + unregister_net_sysctl_table(ieee802154_lowpan->sysctl.frags_hdr); + if (!net_eq(net, &init_net)) + kfree(table); +} + +static struct ctl_table_header *lowpan_ctl_header; + +static int __init lowpan_frags_sysctl_register(void) +{ + lowpan_ctl_header = register_net_sysctl(&init_net, + "net/ieee802154/6lowpan", + lowpan_frags_ctl_table); + return lowpan_ctl_header == NULL ? -ENOMEM : 0; +} + +static void lowpan_frags_sysctl_unregister(void) +{ + unregister_net_sysctl_table(lowpan_ctl_header); +} +#else +static inline int lowpan_frags_ns_sysctl_register(struct net *net) +{ + return 0; +} + +static inline void lowpan_frags_ns_sysctl_unregister(struct net *net) +{ +} + +static inline int __init lowpan_frags_sysctl_register(void) +{ + return 0; +} + +static inline void lowpan_frags_sysctl_unregister(void) +{ +} +#endif + +static int __net_init lowpan_frags_init_net(struct net *net) +{ + struct netns_ieee802154_lowpan *ieee802154_lowpan = + net_ieee802154_lowpan(net); + int res; + + ieee802154_lowpan->frags.high_thresh = IPV6_FRAG_HIGH_THRESH; + ieee802154_lowpan->frags.low_thresh = IPV6_FRAG_LOW_THRESH; + ieee802154_lowpan->frags.timeout = IPV6_FRAG_TIMEOUT; + ieee802154_lowpan->frags.f = &lowpan_frags; + + res = inet_frags_init_net(&ieee802154_lowpan->frags); + if (res < 0) + return res; + res = lowpan_frags_ns_sysctl_register(net); + if (res < 0) + inet_frags_exit_net(&ieee802154_lowpan->frags); + return res; +} + +static void __net_exit lowpan_frags_exit_net(struct net *net) +{ + struct netns_ieee802154_lowpan *ieee802154_lowpan = + net_ieee802154_lowpan(net); + + lowpan_frags_ns_sysctl_unregister(net); + inet_frags_exit_net(&ieee802154_lowpan->frags); +} + +static struct pernet_operations lowpan_frags_ops = { + .init = lowpan_frags_init_net, + .exit = lowpan_frags_exit_net, +}; + +static u32 lowpan_key_hashfn(const void *data, u32 len, u32 seed) +{ + return jhash2(data, + sizeof(struct frag_lowpan_compare_key) / sizeof(u32), seed); +} + +static u32 lowpan_obj_hashfn(const void *data, u32 len, u32 seed) +{ + const struct inet_frag_queue *fq = data; + + return jhash2((const u32 *)&fq->key, + sizeof(struct frag_lowpan_compare_key) / sizeof(u32), seed); +} + +static int lowpan_obj_cmpfn(struct rhashtable_compare_arg *arg, const void *ptr) +{ + const struct frag_lowpan_compare_key *key = arg->key; + const struct inet_frag_queue *fq = ptr; + + return !!memcmp(&fq->key, key, sizeof(*key)); +} + +static const struct rhashtable_params lowpan_rhash_params = { + .head_offset = offsetof(struct inet_frag_queue, node), + .hashfn = lowpan_key_hashfn, + .obj_hashfn = lowpan_obj_hashfn, + .obj_cmpfn = lowpan_obj_cmpfn, + .automatic_shrinking = true, +}; + +int __init lowpan_net_frag_init(void) +{ + int ret; + + lowpan_frags.constructor = lowpan_frag_init; + lowpan_frags.destructor = NULL; + lowpan_frags.qsize = sizeof(struct frag_queue); + lowpan_frags.frag_expire = lowpan_frag_expire; + lowpan_frags.frags_cache_name = lowpan_frags_cache_name; + lowpan_frags.rhash_params = lowpan_rhash_params; + ret = inet_frags_init(&lowpan_frags); + if (ret) + goto out; + + ret = lowpan_frags_sysctl_register(); + if (ret) + goto err_sysctl; + + ret = register_pernet_subsys(&lowpan_frags_ops); + if (ret) + goto err_pernet; +out: + return ret; +err_pernet: + lowpan_frags_sysctl_unregister(); +err_sysctl: + inet_frags_fini(&lowpan_frags); + return ret; +} + +void lowpan_net_frag_exit(void) +{ + lowpan_frags_sysctl_unregister(); + unregister_pernet_subsys(&lowpan_frags_ops); + inet_frags_fini(&lowpan_frags); +} diff --git a/net/ieee802154/6lowpan/rx.c b/net/ieee802154/6lowpan/rx.c new file mode 100644 index 000000000..649e7d45e --- /dev/null +++ b/net/ieee802154/6lowpan/rx.c @@ -0,0 +1,331 @@ +/* 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 <linux/if_arp.h> + +#include <net/6lowpan.h> +#include <net/mac802154.h> +#include <net/ieee802154_netdev.h> + +#include "6lowpan_i.h" + +#define LOWPAN_DISPATCH_FIRST 0xc0 +#define LOWPAN_DISPATCH_FRAG_MASK 0xf8 + +#define LOWPAN_DISPATCH_NALP 0x00 +#define LOWPAN_DISPATCH_ESC 0x40 +#define LOWPAN_DISPATCH_HC1 0x42 +#define LOWPAN_DISPATCH_DFF 0x43 +#define LOWPAN_DISPATCH_BC0 0x50 +#define LOWPAN_DISPATCH_MESH 0x80 + +static int lowpan_give_skb_to_device(struct sk_buff *skb) +{ + skb->protocol = htons(ETH_P_IPV6); + skb->dev->stats.rx_packets++; + skb->dev->stats.rx_bytes += skb->len; + + return netif_rx(skb); +} + +static int lowpan_rx_handlers_result(struct sk_buff *skb, lowpan_rx_result res) +{ + switch (res) { + case RX_CONTINUE: + /* nobody cared about this packet */ + net_warn_ratelimited("%s: received unknown dispatch\n", + __func__); + + /* fall-through */ + case RX_DROP_UNUSABLE: + kfree_skb(skb); + + /* fall-through */ + case RX_DROP: + return NET_RX_DROP; + case RX_QUEUED: + return lowpan_give_skb_to_device(skb); + default: + break; + } + + return NET_RX_DROP; +} + +static inline bool lowpan_is_frag1(u8 dispatch) +{ + return (dispatch & LOWPAN_DISPATCH_FRAG_MASK) == LOWPAN_DISPATCH_FRAG1; +} + +static inline bool lowpan_is_fragn(u8 dispatch) +{ + return (dispatch & LOWPAN_DISPATCH_FRAG_MASK) == LOWPAN_DISPATCH_FRAGN; +} + +static lowpan_rx_result lowpan_rx_h_frag(struct sk_buff *skb) +{ + int ret; + + if (!(lowpan_is_frag1(*skb_network_header(skb)) || + lowpan_is_fragn(*skb_network_header(skb)))) + return RX_CONTINUE; + + ret = lowpan_frag_rcv(skb, *skb_network_header(skb) & + LOWPAN_DISPATCH_FRAG_MASK); + if (ret == 1) + return RX_QUEUED; + + /* Packet is freed by lowpan_frag_rcv on error or put into the frag + * bucket. + */ + return RX_DROP; +} + +int lowpan_iphc_decompress(struct sk_buff *skb) +{ + struct ieee802154_hdr hdr; + + if (ieee802154_hdr_peek_addrs(skb, &hdr) < 0) + return -EINVAL; + + return lowpan_header_decompress(skb, skb->dev, &hdr.dest, &hdr.source); +} + +static lowpan_rx_result lowpan_rx_h_iphc(struct sk_buff *skb) +{ + int ret; + + if (!lowpan_is_iphc(*skb_network_header(skb))) + return RX_CONTINUE; + + /* Setting datagram_offset to zero indicates non frag handling + * while doing lowpan_header_decompress. + */ + lowpan_802154_cb(skb)->d_size = 0; + + ret = lowpan_iphc_decompress(skb); + if (ret < 0) + return RX_DROP_UNUSABLE; + + return RX_QUEUED; +} + +lowpan_rx_result lowpan_rx_h_ipv6(struct sk_buff *skb) +{ + if (!lowpan_is_ipv6(*skb_network_header(skb))) + return RX_CONTINUE; + + /* Pull off the 1-byte of 6lowpan header. */ + skb_pull(skb, 1); + return RX_QUEUED; +} + +static inline bool lowpan_is_esc(u8 dispatch) +{ + return dispatch == LOWPAN_DISPATCH_ESC; +} + +static lowpan_rx_result lowpan_rx_h_esc(struct sk_buff *skb) +{ + if (!lowpan_is_esc(*skb_network_header(skb))) + return RX_CONTINUE; + + net_warn_ratelimited("%s: %s\n", skb->dev->name, + "6LoWPAN ESC not supported\n"); + + return RX_DROP_UNUSABLE; +} + +static inline bool lowpan_is_hc1(u8 dispatch) +{ + return dispatch == LOWPAN_DISPATCH_HC1; +} + +static lowpan_rx_result lowpan_rx_h_hc1(struct sk_buff *skb) +{ + if (!lowpan_is_hc1(*skb_network_header(skb))) + return RX_CONTINUE; + + net_warn_ratelimited("%s: %s\n", skb->dev->name, + "6LoWPAN HC1 not supported\n"); + + return RX_DROP_UNUSABLE; +} + +static inline bool lowpan_is_dff(u8 dispatch) +{ + return dispatch == LOWPAN_DISPATCH_DFF; +} + +static lowpan_rx_result lowpan_rx_h_dff(struct sk_buff *skb) +{ + if (!lowpan_is_dff(*skb_network_header(skb))) + return RX_CONTINUE; + + net_warn_ratelimited("%s: %s\n", skb->dev->name, + "6LoWPAN DFF not supported\n"); + + return RX_DROP_UNUSABLE; +} + +static inline bool lowpan_is_bc0(u8 dispatch) +{ + return dispatch == LOWPAN_DISPATCH_BC0; +} + +static lowpan_rx_result lowpan_rx_h_bc0(struct sk_buff *skb) +{ + if (!lowpan_is_bc0(*skb_network_header(skb))) + return RX_CONTINUE; + + net_warn_ratelimited("%s: %s\n", skb->dev->name, + "6LoWPAN BC0 not supported\n"); + + return RX_DROP_UNUSABLE; +} + +static inline bool lowpan_is_mesh(u8 dispatch) +{ + return (dispatch & LOWPAN_DISPATCH_FIRST) == LOWPAN_DISPATCH_MESH; +} + +static lowpan_rx_result lowpan_rx_h_mesh(struct sk_buff *skb) +{ + if (!lowpan_is_mesh(*skb_network_header(skb))) + return RX_CONTINUE; + + net_warn_ratelimited("%s: %s\n", skb->dev->name, + "6LoWPAN MESH not supported\n"); + + return RX_DROP_UNUSABLE; +} + +static int lowpan_invoke_rx_handlers(struct sk_buff *skb) +{ + lowpan_rx_result res; + +#define CALL_RXH(rxh) \ + do { \ + res = rxh(skb); \ + if (res != RX_CONTINUE) \ + goto rxh_next; \ + } while (0) + + /* likely at first */ + CALL_RXH(lowpan_rx_h_iphc); + CALL_RXH(lowpan_rx_h_frag); + CALL_RXH(lowpan_rx_h_ipv6); + CALL_RXH(lowpan_rx_h_esc); + CALL_RXH(lowpan_rx_h_hc1); + CALL_RXH(lowpan_rx_h_dff); + CALL_RXH(lowpan_rx_h_bc0); + CALL_RXH(lowpan_rx_h_mesh); + +rxh_next: + return lowpan_rx_handlers_result(skb, res); +#undef CALL_RXH +} + +static inline bool lowpan_is_nalp(u8 dispatch) +{ + return (dispatch & LOWPAN_DISPATCH_FIRST) == LOWPAN_DISPATCH_NALP; +} + +/* Lookup for reserved dispatch values at: + * https://www.iana.org/assignments/_6lowpan-parameters/_6lowpan-parameters.xhtml#_6lowpan-parameters-1 + * + * Last Updated: 2015-01-22 + */ +static inline bool lowpan_is_reserved(u8 dispatch) +{ + return ((dispatch >= 0x44 && dispatch <= 0x4F) || + (dispatch >= 0x51 && dispatch <= 0x5F) || + (dispatch >= 0xc8 && dispatch <= 0xdf) || + (dispatch >= 0xe8 && dispatch <= 0xff)); +} + +/* lowpan_rx_h_check checks on generic 6LoWPAN requirements + * in MAC and 6LoWPAN header. + * + * Don't manipulate the skb here, it could be shared buffer. + */ +static inline bool lowpan_rx_h_check(struct sk_buff *skb) +{ + __le16 fc = ieee802154_get_fc_from_skb(skb); + + /* check on ieee802154 conform 6LoWPAN header */ + if (!ieee802154_is_data(fc) || + !ieee802154_skb_is_intra_pan_addressing(fc, skb)) + return false; + + /* check if we can dereference the dispatch */ + if (unlikely(!skb->len)) + return false; + + if (lowpan_is_nalp(*skb_network_header(skb)) || + lowpan_is_reserved(*skb_network_header(skb))) + return false; + + return true; +} + +static int lowpan_rcv(struct sk_buff *skb, struct net_device *wdev, + struct packet_type *pt, struct net_device *orig_wdev) +{ + struct net_device *ldev; + + if (wdev->type != ARPHRD_IEEE802154 || + skb->pkt_type == PACKET_OTHERHOST || + !lowpan_rx_h_check(skb)) + goto drop; + + ldev = wdev->ieee802154_ptr->lowpan_dev; + if (!ldev || !netif_running(ldev)) + goto drop; + + /* Replacing skb->dev and followed rx handlers will manipulate skb. */ + skb = skb_share_check(skb, GFP_ATOMIC); + if (!skb) + goto out; + skb->dev = ldev; + + /* When receive frag1 it's likely that we manipulate the buffer. + * When recevie iphc we manipulate the data buffer. So we need + * to unshare the buffer. + */ + if (lowpan_is_frag1(*skb_network_header(skb)) || + lowpan_is_iphc(*skb_network_header(skb))) { + skb = skb_unshare(skb, GFP_ATOMIC); + if (!skb) + goto out; + } + + return lowpan_invoke_rx_handlers(skb); + +drop: + kfree_skb(skb); +out: + return NET_RX_DROP; +} + +static struct packet_type lowpan_packet_type = { + .type = htons(ETH_P_IEEE802154), + .func = lowpan_rcv, +}; + +void lowpan_rx_init(void) +{ + dev_add_pack(&lowpan_packet_type); +} + +void lowpan_rx_exit(void) +{ + dev_remove_pack(&lowpan_packet_type); +} diff --git a/net/ieee802154/6lowpan/tx.c b/net/ieee802154/6lowpan/tx.c new file mode 100644 index 000000000..8bec82708 --- /dev/null +++ b/net/ieee802154/6lowpan/tx.c @@ -0,0 +1,317 @@ +/* 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) { + skb_put_data(frag, 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); + + skb_put_data(frag, frag_hdr, frag_hdrlen); + skb_put_data(frag, 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; + } +} |