mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-21 19:53:59 +08:00
6lowpan: handling 6lowpan fragmentation via inet_frag api
This patch drops the current way of 6lowpan fragmentation on receiving side and replace it with a implementation which use the inet_frag api. The old fragmentation handling has some race conditions and isn't rfc4944 compatible. Also adding support to match fragments on destination address, source address, tag value and datagram_size which is missing in the current implementation. Signed-off-by: Alexander Aring <alex.aring@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
parent
633fc86ff6
commit
7240cdec60
@ -7,7 +7,16 @@
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#ifndef __NETNS_IEEE802154_6LOWPAN_H__
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#define __NETNS_IEEE802154_6LOWPAN_H__
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struct netns_sysctl_lowpan {
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#ifdef CONFIG_SYSCTL
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struct ctl_table_header *frags_hdr;
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#endif
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};
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struct netns_ieee802154_lowpan {
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struct netns_sysctl_lowpan sysctl;
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struct netns_frags frags;
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u16 max_dsize;
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};
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#endif
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@ -54,6 +54,7 @@
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#include <net/ieee802154_netdev.h>
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#include <net/ipv6.h>
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#include "reassembly.h"
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#include "6lowpan.h"
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static LIST_HEAD(lowpan_devices);
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@ -70,18 +71,6 @@ struct lowpan_dev_record {
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struct list_head list;
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};
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struct lowpan_fragment {
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struct sk_buff *skb; /* skb to be assembled */
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u16 length; /* length to be assemled */
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u32 bytes_rcv; /* bytes received */
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u16 tag; /* current fragment tag */
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struct timer_list timer; /* assembling timer */
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struct list_head list; /* fragments list */
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};
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static LIST_HEAD(lowpan_fragments);
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static DEFINE_SPINLOCK(flist_lock);
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static inline struct
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lowpan_dev_info *lowpan_dev_info(const struct net_device *dev)
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{
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@ -179,69 +168,6 @@ static int lowpan_give_skb_to_devices(struct sk_buff *skb,
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return stat;
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}
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static void lowpan_fragment_timer_expired(unsigned long entry_addr)
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{
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struct lowpan_fragment *entry = (struct lowpan_fragment *)entry_addr;
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pr_debug("timer expired for frame with tag %d\n", entry->tag);
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list_del(&entry->list);
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dev_kfree_skb(entry->skb);
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kfree(entry);
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}
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static struct lowpan_fragment *
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lowpan_alloc_new_frame(struct sk_buff *skb, u16 len, u16 tag)
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{
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struct lowpan_fragment *frame;
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frame = kzalloc(sizeof(struct lowpan_fragment),
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GFP_ATOMIC);
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if (!frame)
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goto frame_err;
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INIT_LIST_HEAD(&frame->list);
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frame->length = len;
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frame->tag = tag;
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/* allocate buffer for frame assembling */
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frame->skb = netdev_alloc_skb_ip_align(skb->dev, frame->length +
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sizeof(struct ipv6hdr));
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if (!frame->skb)
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goto skb_err;
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frame->skb->priority = skb->priority;
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/* reserve headroom for uncompressed ipv6 header */
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skb_reserve(frame->skb, sizeof(struct ipv6hdr));
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skb_put(frame->skb, frame->length);
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/* copy the first control block to keep a
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* trace of the link-layer addresses in case
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* of a link-local compressed address
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*/
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memcpy(frame->skb->cb, skb->cb, sizeof(skb->cb));
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init_timer(&frame->timer);
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/* time out is the same as for ipv6 - 60 sec */
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frame->timer.expires = jiffies + LOWPAN_FRAG_TIMEOUT;
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frame->timer.data = (unsigned long)frame;
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frame->timer.function = lowpan_fragment_timer_expired;
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add_timer(&frame->timer);
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list_add_tail(&frame->list, &lowpan_fragments);
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return frame;
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skb_err:
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kfree(frame);
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frame_err:
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return NULL;
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}
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static int process_data(struct sk_buff *skb)
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{
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u8 iphc0, iphc1;
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@ -255,94 +181,6 @@ static int process_data(struct sk_buff *skb)
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if (lowpan_fetch_skb_u8(skb, &iphc0))
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goto drop;
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/* fragments assembling */
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switch (iphc0 & LOWPAN_DISPATCH_MASK) {
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case LOWPAN_DISPATCH_FRAG1:
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case LOWPAN_DISPATCH_FRAGN:
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{
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struct lowpan_fragment *frame;
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/* slen stores the rightmost 8 bits of the 11 bits length */
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u8 slen, offset = 0;
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u16 len, tag;
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bool found = false;
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if (lowpan_fetch_skb_u8(skb, &slen) || /* frame length */
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lowpan_fetch_skb_u16(skb, &tag)) /* fragment tag */
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goto drop;
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/* adds the 3 MSB to the 8 LSB to retrieve the 11 bits length */
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len = ((iphc0 & 7) << 8) | slen;
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if ((iphc0 & LOWPAN_DISPATCH_MASK) == LOWPAN_DISPATCH_FRAG1) {
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pr_debug("%s received a FRAG1 packet (tag: %d, "
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"size of the entire IP packet: %d)",
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__func__, tag, len);
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} else { /* FRAGN */
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if (lowpan_fetch_skb_u8(skb, &offset))
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goto unlock_and_drop;
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pr_debug("%s received a FRAGN packet (tag: %d, "
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"size of the entire IP packet: %d, "
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"offset: %d)", __func__, tag, len, offset * 8);
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}
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/*
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* check if frame assembling with the same tag is
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* already in progress
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*/
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spin_lock_bh(&flist_lock);
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list_for_each_entry(frame, &lowpan_fragments, list)
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if (frame->tag == tag) {
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found = true;
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break;
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}
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/* alloc new frame structure */
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if (!found) {
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pr_debug("%s first fragment received for tag %d, "
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"begin packet reassembly", __func__, tag);
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frame = lowpan_alloc_new_frame(skb, len, tag);
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if (!frame)
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goto unlock_and_drop;
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}
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/* if payload fits buffer, copy it */
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if (likely((offset * 8 + skb->len) <= frame->length))
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skb_copy_to_linear_data_offset(frame->skb, offset * 8,
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skb->data, skb->len);
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else
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goto unlock_and_drop;
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frame->bytes_rcv += skb->len;
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/* frame assembling complete */
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if ((frame->bytes_rcv == frame->length) &&
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frame->timer.expires > jiffies) {
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/* if timer haven't expired - first of all delete it */
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del_timer_sync(&frame->timer);
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list_del(&frame->list);
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spin_unlock_bh(&flist_lock);
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pr_debug("%s successfully reassembled fragment "
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"(tag %d)", __func__, tag);
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dev_kfree_skb(skb);
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skb = frame->skb;
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kfree(frame);
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if (lowpan_fetch_skb_u8(skb, &iphc0))
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goto drop;
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break;
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}
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spin_unlock_bh(&flist_lock);
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return kfree_skb(skb), 0;
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}
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default:
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break;
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}
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if (lowpan_fetch_skb_u8(skb, &iphc1))
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goto drop;
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@ -355,8 +193,6 @@ static int process_data(struct sk_buff *skb)
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IEEE802154_ADDR_LEN, iphc0, iphc1,
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lowpan_give_skb_to_devices);
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unlock_and_drop:
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spin_unlock_bh(&flist_lock);
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drop:
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kfree_skb(skb);
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return -EINVAL;
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@ -603,44 +439,53 @@ static int lowpan_rcv(struct sk_buff *skb, struct net_device *dev,
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struct packet_type *pt, struct net_device *orig_dev)
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{
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struct sk_buff *local_skb;
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int ret;
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if (!netif_running(dev))
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goto drop;
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goto drop_skb;
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if (dev->type != ARPHRD_IEEE802154)
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goto drop;
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goto drop_skb;
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local_skb = skb_clone(skb, GFP_ATOMIC);
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if (!local_skb)
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goto drop_skb;
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kfree_skb(skb);
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/* check that it's our buffer */
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if (skb->data[0] == LOWPAN_DISPATCH_IPV6) {
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/* Copy the packet so that the IPv6 header is
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* properly aligned.
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*/
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local_skb = skb_copy_expand(skb, NET_SKB_PAD - 1,
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skb_tailroom(skb), GFP_ATOMIC);
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if (!local_skb)
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goto drop;
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local_skb->protocol = htons(ETH_P_IPV6);
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local_skb->pkt_type = PACKET_HOST;
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/* Pull off the 1-byte of 6lowpan header. */
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skb_pull(local_skb, 1);
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lowpan_give_skb_to_devices(local_skb, NULL);
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kfree_skb(local_skb);
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kfree_skb(skb);
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ret = lowpan_give_skb_to_devices(local_skb, NULL);
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if (ret == NET_RX_DROP)
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goto drop;
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} else {
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switch (skb->data[0] & 0xe0) {
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case LOWPAN_DISPATCH_IPHC: /* ipv6 datagram */
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case LOWPAN_DISPATCH_FRAG1: /* first fragment header */
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case LOWPAN_DISPATCH_FRAGN: /* next fragments headers */
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local_skb = skb_clone(skb, GFP_ATOMIC);
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if (!local_skb)
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ret = process_data(local_skb);
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if (ret == NET_RX_DROP)
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goto drop;
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process_data(local_skb);
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kfree_skb(skb);
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break;
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case LOWPAN_DISPATCH_FRAG1: /* first fragment header */
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ret = lowpan_frag_rcv(local_skb, LOWPAN_DISPATCH_FRAG1);
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if (ret == 1) {
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ret = process_data(local_skb);
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if (ret == NET_RX_DROP)
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goto drop;
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}
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break;
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case LOWPAN_DISPATCH_FRAGN: /* next fragments headers */
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ret = lowpan_frag_rcv(local_skb, LOWPAN_DISPATCH_FRAGN);
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if (ret == 1) {
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ret = process_data(local_skb);
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if (ret == NET_RX_DROP)
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goto drop;
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}
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break;
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default:
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break;
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@ -648,9 +493,9 @@ static int lowpan_rcv(struct sk_buff *skb, struct net_device *dev,
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}
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return NET_RX_SUCCESS;
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drop:
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drop_skb:
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kfree_skb(skb);
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drop:
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return NET_RX_DROP;
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}
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@ -778,43 +623,40 @@ static int __init lowpan_init_module(void)
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{
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int err = 0;
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err = lowpan_netlink_init();
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err = lowpan_net_frag_init();
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if (err < 0)
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goto out;
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err = lowpan_netlink_init();
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if (err < 0)
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goto out_frag;
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dev_add_pack(&lowpan_packet_type);
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err = register_netdevice_notifier(&lowpan_dev_notifier);
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if (err < 0) {
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dev_remove_pack(&lowpan_packet_type);
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lowpan_netlink_fini();
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}
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if (err < 0)
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goto out_pack;
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return 0;
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out_pack:
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dev_remove_pack(&lowpan_packet_type);
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lowpan_netlink_fini();
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out_frag:
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lowpan_net_frag_exit();
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out:
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return err;
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}
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static void __exit lowpan_cleanup_module(void)
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{
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struct lowpan_fragment *frame, *tframe;
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lowpan_netlink_fini();
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dev_remove_pack(&lowpan_packet_type);
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unregister_netdevice_notifier(&lowpan_dev_notifier);
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lowpan_net_frag_exit();
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/* Now 6lowpan packet_type is removed, so no new fragments are
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* expected on RX, therefore that's the time to clean incomplete
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* fragments.
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*/
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spin_lock_bh(&flist_lock);
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list_for_each_entry_safe(frame, tframe, &lowpan_fragments, list) {
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del_timer_sync(&frame->timer);
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list_del(&frame->list);
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dev_kfree_skb(frame->skb);
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kfree(frame);
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}
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spin_unlock_bh(&flist_lock);
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unregister_netdevice_notifier(&lowpan_dev_notifier);
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}
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module_init(lowpan_init_module);
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@ -2,6 +2,6 @@ obj-$(CONFIG_IEEE802154) += ieee802154.o af_802154.o
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obj-$(CONFIG_IEEE802154_6LOWPAN) += 6lowpan.o
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obj-$(CONFIG_6LOWPAN_IPHC) += 6lowpan_iphc.o
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6lowpan-y := 6lowpan_rtnl.o
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6lowpan-y := 6lowpan_rtnl.o reassembly.o
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ieee802154-y := netlink.o nl-mac.o nl-phy.o nl_policy.o wpan-class.o
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af_802154-y := af_ieee802154.o raw.o dgram.o
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564
net/ieee802154/reassembly.c
Normal file
564
net/ieee802154/reassembly.c
Normal file
@ -0,0 +1,564 @@
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/* 6LoWPAN fragment reassembly
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*
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*
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* Authors:
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* Alexander Aring <aar@pengutronix.de>
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*
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* Based on: net/ipv6/reassembly.c
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*/
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#define pr_fmt(fmt) "6LoWPAN: " fmt
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#include <linux/net.h>
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#include <linux/list.h>
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#include <linux/netdevice.h>
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#include <linux/random.h>
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#include <linux/jhash.h>
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#include <linux/skbuff.h>
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#include <linux/slab.h>
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#include <linux/export.h>
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#include <net/ieee802154_netdev.h>
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#include <net/ipv6.h>
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#include <net/inet_frag.h>
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#include "6lowpan.h"
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#include "reassembly.h"
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static struct inet_frags lowpan_frags;
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static int lowpan_frag_reasm(struct lowpan_frag_queue *fq,
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struct sk_buff *prev, struct net_device *dev);
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static unsigned int lowpan_hash_frag(__be16 tag, __be16 d_size,
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const struct ieee802154_addr *saddr,
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const struct ieee802154_addr *daddr)
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{
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u32 c;
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net_get_random_once(&lowpan_frags.rnd, sizeof(lowpan_frags.rnd));
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c = jhash_3words(ieee802154_addr_hash(saddr),
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ieee802154_addr_hash(daddr),
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(__force u32)(tag + (d_size << 16)),
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lowpan_frags.rnd);
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return c & (INETFRAGS_HASHSZ - 1);
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}
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static unsigned int lowpan_hashfn(struct inet_frag_queue *q)
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{
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struct lowpan_frag_queue *fq;
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fq = container_of(q, struct lowpan_frag_queue, q);
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return lowpan_hash_frag(fq->tag, fq->d_size, &fq->saddr, &fq->daddr);
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}
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bool lowpan_frag_match(struct inet_frag_queue *q, void *a)
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{
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struct lowpan_frag_queue *fq;
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struct lowpan_create_arg *arg = a;
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fq = container_of(q, struct lowpan_frag_queue, q);
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return fq->tag == arg->tag && fq->d_size == arg->d_size &&
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ieee802154_addr_addr_equal(&fq->saddr, arg->src) &&
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ieee802154_addr_addr_equal(&fq->daddr, arg->dst);
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}
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EXPORT_SYMBOL(lowpan_frag_match);
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void lowpan_frag_init(struct inet_frag_queue *q, void *a)
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{
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struct lowpan_frag_queue *fq;
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struct lowpan_create_arg *arg = a;
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fq = container_of(q, struct lowpan_frag_queue, q);
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fq->tag = arg->tag;
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fq->d_size = arg->d_size;
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fq->saddr = *arg->src;
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fq->daddr = *arg->dst;
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}
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EXPORT_SYMBOL(lowpan_frag_init);
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void lowpan_expire_frag_queue(struct frag_queue *fq, struct inet_frags *frags)
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{
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spin_lock(&fq->q.lock);
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if (fq->q.last_in & INET_FRAG_COMPLETE)
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goto out;
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inet_frag_kill(&fq->q, frags);
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out:
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spin_unlock(&fq->q.lock);
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||||
inet_frag_put(&fq->q, frags);
|
||||
}
|
||||
EXPORT_SYMBOL(lowpan_expire_frag_queue);
|
||||
|
||||
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);
|
||||
|
||||
lowpan_expire_frag_queue(fq, &lowpan_frags);
|
||||
}
|
||||
|
||||
static inline struct lowpan_frag_queue *
|
||||
fq_find(struct net *net, const struct ieee802154_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;
|
||||
|
||||
arg.tag = frag_info->d_tag;
|
||||
arg.d_size = frag_info->d_size;
|
||||
arg.src = src;
|
||||
arg.dst = dst;
|
||||
|
||||
read_lock(&lowpan_frags.lock);
|
||||
hash = lowpan_hash_frag(frag_info->d_tag, frag_info->d_size, src, dst);
|
||||
|
||||
q = inet_frag_find(&net->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.last_in & INET_FRAG_COMPLETE)
|
||||
goto err;
|
||||
|
||||
offset = mac_cb(skb)->frag_info.d_offset << 3;
|
||||
end = mac_cb(skb)->frag_info.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.last_in & INET_FRAG_LAST_IN) && end != fq->q.len))
|
||||
goto err;
|
||||
fq->q.last_in |= INET_FRAG_LAST_IN;
|
||||
fq->q.len = end;
|
||||
} else {
|
||||
if (end > fq->q.len) {
|
||||
/* Some bits beyond end -> corruption. */
|
||||
if (fq->q.last_in & 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 || mac_cb(prev)->frag_info.d_offset <
|
||||
mac_cb(skb)->frag_info.d_offset) {
|
||||
next = NULL;
|
||||
goto found;
|
||||
}
|
||||
prev = NULL;
|
||||
for (next = fq->q.fragments; next != NULL; next = next->next) {
|
||||
if (mac_cb(next)->frag_info.d_offset >=
|
||||
mac_cb(skb)->frag_info.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.last_in |= INET_FRAG_FIRST_IN;
|
||||
} else {
|
||||
fq->q.meat += skb->len;
|
||||
}
|
||||
add_frag_mem_limit(&fq->q, skb->truesize);
|
||||
|
||||
if (fq->q.last_in == (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;
|
||||
}
|
||||
|
||||
inet_frag_lru_move(&fq->q);
|
||||
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 ieee802154_frag_info *frag_info)
|
||||
{
|
||||
bool fail;
|
||||
u8 pattern = 0, low = 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, &frag_info->d_tag, 2);
|
||||
|
||||
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 ieee802154_frag_info *frag_info = &mac_cb(skb)->frag_info;
|
||||
int err;
|
||||
|
||||
err = lowpan_get_frag_info(skb, frag_type, frag_info);
|
||||
if (err < 0)
|
||||
goto err;
|
||||
|
||||
if (frag_info->d_size > net->ieee802154_lowpan.max_dsize)
|
||||
goto err;
|
||||
|
||||
inet_frag_evictor(&net->ieee802154_lowpan.frags, &lowpan_frags, false);
|
||||
|
||||
fq = fq_find(net, frag_info, &mac_cb(skb)->sa, &mac_cb(skb)->da);
|
||||
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 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
|
||||
},
|
||||
{
|
||||
.procname = "6lowpanfrag_low_thresh",
|
||||
.data = &init_net.ieee802154_lowpan.frags.low_thresh,
|
||||
.maxlen = sizeof(int),
|
||||
.mode = 0644,
|
||||
.proc_handler = proc_dointvec
|
||||
},
|
||||
{
|
||||
.procname = "6lowpanfrag_time",
|
||||
.data = &init_net.ieee802154_lowpan.frags.timeout,
|
||||
.maxlen = sizeof(int),
|
||||
.mode = 0644,
|
||||
.proc_handler = proc_dointvec_jiffies,
|
||||
},
|
||||
{
|
||||
.procname = "6lowpanfrag_max_datagram_size",
|
||||
.data = &init_net.ieee802154_lowpan.max_dsize,
|
||||
.maxlen = sizeof(int),
|
||||
.mode = 0644,
|
||||
.proc_handler = proc_dointvec
|
||||
},
|
||||
{ }
|
||||
};
|
||||
|
||||
static struct ctl_table lowpan_frags_ctl_table[] = {
|
||||
{
|
||||
.procname = "6lowpanfrag_secret_interval",
|
||||
.data = &lowpan_frags.secret_interval,
|
||||
.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;
|
||||
|
||||
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 = &net->ieee802154_lowpan.frags.high_thresh;
|
||||
table[1].data = &net->ieee802154_lowpan.frags.low_thresh;
|
||||
table[2].data = &net->ieee802154_lowpan.frags.timeout;
|
||||
table[2].data = &net->ieee802154_lowpan.max_dsize;
|
||||
|
||||
/* 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;
|
||||
|
||||
net->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;
|
||||
|
||||
table = net->ieee802154_lowpan.sysctl.frags_hdr->ctl_table_arg;
|
||||
unregister_net_sysctl_table(net->ieee802154_lowpan.sysctl.frags_hdr);
|
||||
if (!net_eq(net, &init_net))
|
||||
kfree(table);
|
||||
}
|
||||
|
||||
static struct ctl_table_header *lowpan_ctl_header;
|
||||
|
||||
static int 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 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)
|
||||
{
|
||||
net->ieee802154_lowpan.frags.high_thresh = IPV6_FRAG_HIGH_THRESH;
|
||||
net->ieee802154_lowpan.frags.low_thresh = IPV6_FRAG_LOW_THRESH;
|
||||
net->ieee802154_lowpan.frags.timeout = IPV6_FRAG_TIMEOUT;
|
||||
net->ieee802154_lowpan.max_dsize = 0xFFFF;
|
||||
|
||||
inet_frags_init_net(&net->ieee802154_lowpan.frags);
|
||||
|
||||
return lowpan_frags_ns_sysctl_register(net);
|
||||
}
|
||||
|
||||
static void __net_exit lowpan_frags_exit_net(struct net *net)
|
||||
{
|
||||
lowpan_frags_ns_sysctl_unregister(net);
|
||||
inet_frags_exit_net(&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)
|
||||
goto out;
|
||||
|
||||
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.secret_interval = 10 * 60 * HZ;
|
||||
inet_frags_init(&lowpan_frags);
|
||||
err_pernet:
|
||||
lowpan_frags_sysctl_unregister();
|
||||
out:
|
||||
return ret;
|
||||
}
|
||||
|
||||
void lowpan_net_frag_exit(void)
|
||||
{
|
||||
inet_frags_fini(&lowpan_frags);
|
||||
lowpan_frags_sysctl_unregister();
|
||||
unregister_pernet_subsys(&lowpan_frags_ops);
|
||||
}
|
66
net/ieee802154/reassembly.h
Normal file
66
net/ieee802154/reassembly.h
Normal file
@ -0,0 +1,66 @@
|
||||
#ifndef __IEEE802154_6LOWPAN_REASSEMBLY_H__
|
||||
#define __IEEE802154_6LOWPAN_REASSEMBLY_H__
|
||||
|
||||
#include <net/inet_frag.h>
|
||||
|
||||
struct lowpan_create_arg {
|
||||
__be16 tag;
|
||||
u16 d_size;
|
||||
const struct ieee802154_addr *src;
|
||||
const struct ieee802154_addr *dst;
|
||||
};
|
||||
|
||||
/* Equivalent of ipv4 struct ip
|
||||
*/
|
||||
struct lowpan_frag_queue {
|
||||
struct inet_frag_queue q;
|
||||
|
||||
__be16 tag;
|
||||
u16 d_size;
|
||||
struct ieee802154_addr saddr;
|
||||
struct ieee802154_addr daddr;
|
||||
};
|
||||
|
||||
static inline u32 ieee802154_addr_hash(const struct ieee802154_addr *a)
|
||||
{
|
||||
switch (a->addr_type) {
|
||||
case IEEE802154_ADDR_LONG:
|
||||
return (__force u32)((((u32 *)a->hwaddr))[0] ^
|
||||
((u32 *)(a->hwaddr))[1]);
|
||||
case IEEE802154_ADDR_SHORT:
|
||||
return (__force u32)(a->short_addr);
|
||||
default:
|
||||
return 0;
|
||||
}
|
||||
}
|
||||
|
||||
static inline bool ieee802154_addr_addr_equal(const struct ieee802154_addr *a1,
|
||||
const struct ieee802154_addr *a2)
|
||||
{
|
||||
if (a1->pan_id != a2->pan_id)
|
||||
return false;
|
||||
|
||||
if (a1->addr_type != a2->addr_type)
|
||||
return false;
|
||||
|
||||
switch (a1->addr_type) {
|
||||
case IEEE802154_ADDR_LONG:
|
||||
if (memcmp(a1->hwaddr, a2->hwaddr, IEEE802154_ADDR_LEN))
|
||||
return false;
|
||||
break;
|
||||
case IEEE802154_ADDR_SHORT:
|
||||
if (a1->short_addr != a2->short_addr)
|
||||
return false;
|
||||
break;
|
||||
default:
|
||||
return false;
|
||||
}
|
||||
|
||||
return true;
|
||||
}
|
||||
|
||||
int lowpan_frag_rcv(struct sk_buff *skb, const u8 frag_type);
|
||||
void lowpan_net_frag_exit(void);
|
||||
int lowpan_net_frag_init(void);
|
||||
|
||||
#endif /* __IEEE802154_6LOWPAN_REASSEMBLY_H__ */
|
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Block a user