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Diffstat (limited to 'net/ieee802154/reassembly.c')
-rw-r--r--net/ieee802154/reassembly.c585
1 files changed, 0 insertions, 585 deletions
diff --git a/net/ieee802154/reassembly.c b/net/ieee802154/reassembly.c
deleted file mode 100644
index 9d980ed3ffe2..000000000000
--- a/net/ieee802154/reassembly.c
+++ /dev/null
@@ -1,585 +0,0 @@
-/* 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.h>
-#include <net/inet_frag.h>
-
-#include "reassembly.h"
-
-static const char lowpan_frags_cache_name[] = "lowpan-frags";
-
-struct lowpan_frag_info {
- u16 d_tag;
- u16 d_size;
- u8 d_offset;
-};
-
-static struct lowpan_frag_info *lowpan_cb(struct sk_buff *skb)
-{
- return (struct lowpan_frag_info *)skb->cb;
-}
-
-static struct inet_frags lowpan_frags;
-
-static int lowpan_frag_reasm(struct lowpan_frag_queue *fq,
- struct sk_buff *prev, struct net_device *dev);
-
-static unsigned int lowpan_hash_frag(u16 tag, u16 d_size,
- const struct ieee802154_addr *saddr,
- const struct ieee802154_addr *daddr)
-{
- net_get_random_once(&lowpan_frags.rnd, sizeof(lowpan_frags.rnd));
- return jhash_3words(ieee802154_addr_hash(saddr),
- ieee802154_addr_hash(daddr),
- (__force u32)(tag + (d_size << 16)),
- lowpan_frags.rnd);
-}
-
-static unsigned int lowpan_hashfn(const struct inet_frag_queue *q)
-{
- const struct lowpan_frag_queue *fq;
-
- fq = container_of(q, struct lowpan_frag_queue, q);
- return lowpan_hash_frag(fq->tag, fq->d_size, &fq->saddr, &fq->daddr);
-}
-
-static bool lowpan_frag_match(const struct inet_frag_queue *q, const void *a)
-{
- const struct lowpan_frag_queue *fq;
- const struct lowpan_create_arg *arg = a;
-
- fq = container_of(q, struct lowpan_frag_queue, q);
- return fq->tag == arg->tag && fq->d_size == arg->d_size &&
- ieee802154_addr_equal(&fq->saddr, arg->src) &&
- ieee802154_addr_equal(&fq->daddr, arg->dst);
-}
-
-static void lowpan_frag_init(struct inet_frag_queue *q, const void *a)
-{
- const struct lowpan_create_arg *arg = a;
- struct lowpan_frag_queue *fq;
-
- fq = container_of(q, struct lowpan_frag_queue, q);
-
- fq->tag = arg->tag;
- fq->d_size = arg->d_size;
- fq->saddr = *arg->src;
- fq->daddr = *arg->dst;
-}
-
-static void lowpan_frag_expire(unsigned long data)
-{
- struct frag_queue *fq;
- struct net *net;
-
- fq = container_of((struct inet_frag_queue *)data, struct frag_queue, q);
- net = container_of(fq->q.net, struct net, ieee802154_lowpan.frags);
-
- spin_lock(&fq->q.lock);
-
- if (fq->q.flags & INET_FRAG_COMPLETE)
- goto out;
-
- inet_frag_kill(&fq->q, &lowpan_frags);
-out:
- spin_unlock(&fq->q.lock);
- inet_frag_put(&fq->q, &lowpan_frags);
-}
-
-static inline struct lowpan_frag_queue *
-fq_find(struct net *net, const struct lowpan_frag_info *frag_info,
- const struct ieee802154_addr *src,
- const struct ieee802154_addr *dst)
-{
- struct inet_frag_queue *q;
- struct lowpan_create_arg arg;
- unsigned int hash;
- struct netns_ieee802154_lowpan *ieee802154_lowpan =
- net_ieee802154_lowpan(net);
-
- arg.tag = frag_info->d_tag;
- arg.d_size = frag_info->d_size;
- arg.src = src;
- arg.dst = dst;
-
- hash = lowpan_hash_frag(frag_info->d_tag, frag_info->d_size, src, dst);
-
- q = inet_frag_find(&ieee802154_lowpan->frags,
- &lowpan_frags, &arg, hash);
- if (IS_ERR_OR_NULL(q)) {
- inet_frag_maybe_warn_overflow(q, pr_fmt());
- 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, const u8 frag_type)
-{
- struct sk_buff *prev, *next;
- struct net_device *dev;
- int end, offset;
-
- if (fq->q.flags & INET_FRAG_COMPLETE)
- goto err;
-
- offset = lowpan_cb(skb)->d_offset << 3;
- end = lowpan_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_cb(prev)->d_offset < lowpan_cb(skb)->d_offset) {
- next = NULL;
- goto found;
- }
- prev = NULL;
- for (next = fq->q.fragments; next != NULL; next = next->next) {
- if (lowpan_cb(next)->d_offset >= lowpan_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;
-
- dev = skb->dev;
- if (dev)
- skb->dev = NULL;
-
- fq->q.stamp = skb->tstamp;
- if (frag_type == LOWPAN_DISPATCH_FRAG1) {
- /* Calculate uncomp. 6lowpan header to estimate full size */
- fq->q.meat += lowpan_uncompress_size(skb, NULL);
- fq->q.flags |= INET_FRAG_FIRST_IN;
- } else {
- fq->q.meat += skb->len;
- }
- add_frag_mem_limit(&fq->q, 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, dev);
- 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 *dev)
-{
- struct sk_buff *fp, *head = fq->q.fragments;
- int sum_truesize;
-
- inet_frag_kill(&fq->q, &lowpan_frags);
-
- /* 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, 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, sum_truesize);
-
- head->next = NULL;
- head->dev = dev;
- 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_get_frag_info(struct sk_buff *skb, const u8 frag_type,
- struct lowpan_frag_info *frag_info)
-{
- bool fail;
- u8 pattern = 0, low = 0;
- __be16 d_tag = 0;
-
- fail = lowpan_fetch_skb(skb, &pattern, 1);
- fail |= lowpan_fetch_skb(skb, &low, 1);
- frag_info->d_size = (pattern & 7) << 8 | low;
- fail |= lowpan_fetch_skb(skb, &d_tag, 2);
- frag_info->d_tag = ntohs(d_tag);
-
- if (frag_type == LOWPAN_DISPATCH_FRAGN) {
- fail |= lowpan_fetch_skb(skb, &frag_info->d_offset, 1);
- } else {
- skb_reset_network_header(skb);
- frag_info->d_offset = 0;
- }
-
- if (unlikely(fail))
- return -EIO;
-
- return 0;
-}
-
-int lowpan_frag_rcv(struct sk_buff *skb, const u8 frag_type)
-{
- struct lowpan_frag_queue *fq;
- struct net *net = dev_net(skb->dev);
- struct lowpan_frag_info *frag_info = lowpan_cb(skb);
- struct ieee802154_addr source, dest;
- int err;
-
- source = mac_cb(skb)->source;
- dest = mac_cb(skb)->dest;
-
- err = lowpan_get_frag_info(skb, frag_type, frag_info);
- if (err < 0)
- goto err;
-
- if (frag_info->d_size > IPV6_MIN_MTU) {
- net_warn_ratelimited("lowpan_frag_rcv: datagram size exceeds MTU\n");
- goto err;
- }
-
- fq = fq_find(net, frag_info, &source, &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, &lowpan_frags);
- return ret;
- }
-
-err:
- kfree_skb(skb);
- return -1;
-}
-EXPORT_SYMBOL(lowpan_frag_rcv);
-
-#ifdef CONFIG_SYSCTL
-static int zero;
-
-static struct ctl_table lowpan_frags_ns_ctl_table[] = {
- {
- .procname = "6lowpanfrag_high_thresh",
- .data = &init_net.ieee802154_lowpan.frags.high_thresh,
- .maxlen = sizeof(int),
- .mode = 0644,
- .proc_handler = proc_dointvec_minmax,
- .extra1 = &init_net.ieee802154_lowpan.frags.low_thresh
- },
- {
- .procname = "6lowpanfrag_low_thresh",
- .data = &init_net.ieee802154_lowpan.frags.low_thresh,
- .maxlen = sizeof(int),
- .mode = 0644,
- .proc_handler = proc_dointvec_minmax,
- .extra1 = &zero,
- .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);
-
- 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;
-
- inet_frags_init_net(&ieee802154_lowpan->frags);
-
- return lowpan_frags_ns_sysctl_register(net);
-}
-
-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, &lowpan_frags);
-}
-
-static struct pernet_operations lowpan_frags_ops = {
- .init = lowpan_frags_init_net,
- .exit = lowpan_frags_exit_net,
-};
-
-int __init lowpan_net_frag_init(void)
-{
- int ret;
-
- ret = lowpan_frags_sysctl_register();
- if (ret)
- return ret;
-
- ret = register_pernet_subsys(&lowpan_frags_ops);
- if (ret)
- goto err_pernet;
-
- lowpan_frags.hashfn = lowpan_hashfn;
- lowpan_frags.constructor = lowpan_frag_init;
- lowpan_frags.destructor = NULL;
- lowpan_frags.skb_free = NULL;
- lowpan_frags.qsize = sizeof(struct frag_queue);
- lowpan_frags.match = lowpan_frag_match;
- lowpan_frags.frag_expire = lowpan_frag_expire;
- lowpan_frags.frags_cache_name = lowpan_frags_cache_name;
- ret = inet_frags_init(&lowpan_frags);
- if (ret)
- goto err_pernet;
-
- return ret;
-err_pernet:
- lowpan_frags_sysctl_unregister();
- return ret;
-}
-
-void lowpan_net_frag_exit(void)
-{
- inet_frags_fini(&lowpan_frags);
- lowpan_frags_sysctl_unregister();
- unregister_pernet_subsys(&lowpan_frags_ops);
-}
generated by cgit v1.2.3 (git 2.0.4) at 2025-06-05 20:31:14 +0000