forked from Minki/linux
net: IP defrag: encapsulate rbtree defrag code into callable functions
This is a refactoring patch: without changing runtime behavior, it moves rbtree-related code from IPv4-specific files/functions into .h/.c defrag files shared with IPv6 defragmentation code. Signed-off-by: Peter Oskolkov <posk@google.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Florian Westphal <fw@strlen.de> Cc: Tom Herbert <tom@herbertland.com> Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
parent
ccaceadc4e
commit
c23f35d19d
@ -77,8 +77,8 @@ struct inet_frag_queue {
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struct timer_list timer;
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struct timer_list timer;
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spinlock_t lock;
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spinlock_t lock;
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refcount_t refcnt;
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refcount_t refcnt;
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struct sk_buff *fragments; /* Used in IPv6. */
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struct sk_buff *fragments; /* used in 6lopwpan IPv6. */
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struct rb_root rb_fragments; /* Used in IPv4. */
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struct rb_root rb_fragments; /* Used in IPv4/IPv6. */
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struct sk_buff *fragments_tail;
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struct sk_buff *fragments_tail;
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struct sk_buff *last_run_head;
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struct sk_buff *last_run_head;
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ktime_t stamp;
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ktime_t stamp;
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@ -153,4 +153,16 @@ static inline void add_frag_mem_limit(struct netns_frags *nf, long val)
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extern const u8 ip_frag_ecn_table[16];
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extern const u8 ip_frag_ecn_table[16];
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/* Return values of inet_frag_queue_insert() */
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#define IPFRAG_OK 0
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#define IPFRAG_DUP 1
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#define IPFRAG_OVERLAP 2
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int inet_frag_queue_insert(struct inet_frag_queue *q, struct sk_buff *skb,
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int offset, int end);
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void *inet_frag_reasm_prepare(struct inet_frag_queue *q, struct sk_buff *skb,
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struct sk_buff *parent);
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void inet_frag_reasm_finish(struct inet_frag_queue *q, struct sk_buff *head,
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void *reasm_data);
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struct sk_buff *inet_frag_pull_head(struct inet_frag_queue *q);
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#endif
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#endif
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@ -25,6 +25,62 @@
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#include <net/sock.h>
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#include <net/sock.h>
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#include <net/inet_frag.h>
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#include <net/inet_frag.h>
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#include <net/inet_ecn.h>
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#include <net/inet_ecn.h>
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#include <net/ip.h>
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#include <net/ipv6.h>
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/* Use skb->cb to track consecutive/adjacent fragments coming at
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* the end of the queue. Nodes in the rb-tree queue will
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* contain "runs" of one or more adjacent fragments.
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*
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* Invariants:
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* - next_frag is NULL at the tail of a "run";
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* - the head of a "run" has the sum of all fragment lengths in frag_run_len.
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*/
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struct ipfrag_skb_cb {
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union {
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struct inet_skb_parm h4;
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struct inet6_skb_parm h6;
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};
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struct sk_buff *next_frag;
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int frag_run_len;
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};
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#define FRAG_CB(skb) ((struct ipfrag_skb_cb *)((skb)->cb))
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static void fragcb_clear(struct sk_buff *skb)
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{
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RB_CLEAR_NODE(&skb->rbnode);
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FRAG_CB(skb)->next_frag = NULL;
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FRAG_CB(skb)->frag_run_len = skb->len;
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}
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/* Append skb to the last "run". */
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static void fragrun_append_to_last(struct inet_frag_queue *q,
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struct sk_buff *skb)
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{
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fragcb_clear(skb);
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FRAG_CB(q->last_run_head)->frag_run_len += skb->len;
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FRAG_CB(q->fragments_tail)->next_frag = skb;
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q->fragments_tail = skb;
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}
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/* Create a new "run" with the skb. */
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static void fragrun_create(struct inet_frag_queue *q, struct sk_buff *skb)
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{
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BUILD_BUG_ON(sizeof(struct ipfrag_skb_cb) > sizeof(skb->cb));
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fragcb_clear(skb);
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if (q->last_run_head)
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rb_link_node(&skb->rbnode, &q->last_run_head->rbnode,
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&q->last_run_head->rbnode.rb_right);
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else
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rb_link_node(&skb->rbnode, NULL, &q->rb_fragments.rb_node);
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rb_insert_color(&skb->rbnode, &q->rb_fragments);
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q->fragments_tail = skb;
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q->last_run_head = skb;
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}
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/* Given the OR values of all fragments, apply RFC 3168 5.3 requirements
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/* Given the OR values of all fragments, apply RFC 3168 5.3 requirements
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* Value : 0xff if frame should be dropped.
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* Value : 0xff if frame should be dropped.
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@ -123,6 +179,28 @@ static void inet_frag_destroy_rcu(struct rcu_head *head)
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kmem_cache_free(f->frags_cachep, q);
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kmem_cache_free(f->frags_cachep, q);
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}
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}
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unsigned int inet_frag_rbtree_purge(struct rb_root *root)
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{
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struct rb_node *p = rb_first(root);
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unsigned int sum = 0;
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while (p) {
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struct sk_buff *skb = rb_entry(p, struct sk_buff, rbnode);
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p = rb_next(p);
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rb_erase(&skb->rbnode, root);
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while (skb) {
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struct sk_buff *next = FRAG_CB(skb)->next_frag;
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sum += skb->truesize;
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kfree_skb(skb);
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skb = next;
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}
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}
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return sum;
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}
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EXPORT_SYMBOL(inet_frag_rbtree_purge);
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void inet_frag_destroy(struct inet_frag_queue *q)
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void inet_frag_destroy(struct inet_frag_queue *q)
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{
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{
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struct sk_buff *fp;
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struct sk_buff *fp;
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@ -224,3 +302,218 @@ struct inet_frag_queue *inet_frag_find(struct netns_frags *nf, void *key)
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return fq;
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return fq;
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}
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}
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EXPORT_SYMBOL(inet_frag_find);
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EXPORT_SYMBOL(inet_frag_find);
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int inet_frag_queue_insert(struct inet_frag_queue *q, struct sk_buff *skb,
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int offset, int end)
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{
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struct sk_buff *last = q->fragments_tail;
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/* RFC5722, Section 4, amended by Errata ID : 3089
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* When reassembling an IPv6 datagram, if
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* one or more its constituent fragments is determined to be an
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* overlapping fragment, the entire datagram (and any constituent
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* fragments) MUST be silently discarded.
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*
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* Duplicates, however, should be ignored (i.e. skb dropped, but the
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* queue/fragments kept for later reassembly).
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*/
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if (!last)
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fragrun_create(q, skb); /* First fragment. */
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else if (last->ip_defrag_offset + last->len < end) {
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/* This is the common case: skb goes to the end. */
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/* Detect and discard overlaps. */
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if (offset < last->ip_defrag_offset + last->len)
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return IPFRAG_OVERLAP;
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if (offset == last->ip_defrag_offset + last->len)
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fragrun_append_to_last(q, skb);
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else
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fragrun_create(q, skb);
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} else {
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/* Binary search. Note that skb can become the first fragment,
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* but not the last (covered above).
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*/
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struct rb_node **rbn, *parent;
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rbn = &q->rb_fragments.rb_node;
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do {
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struct sk_buff *curr;
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int curr_run_end;
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parent = *rbn;
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curr = rb_to_skb(parent);
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curr_run_end = curr->ip_defrag_offset +
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FRAG_CB(curr)->frag_run_len;
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if (end <= curr->ip_defrag_offset)
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rbn = &parent->rb_left;
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else if (offset >= curr_run_end)
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rbn = &parent->rb_right;
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else if (offset >= curr->ip_defrag_offset &&
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end <= curr_run_end)
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return IPFRAG_DUP;
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else
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return IPFRAG_OVERLAP;
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} while (*rbn);
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/* Here we have parent properly set, and rbn pointing to
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* one of its NULL left/right children. Insert skb.
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*/
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fragcb_clear(skb);
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rb_link_node(&skb->rbnode, parent, rbn);
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rb_insert_color(&skb->rbnode, &q->rb_fragments);
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}
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skb->ip_defrag_offset = offset;
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return IPFRAG_OK;
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}
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EXPORT_SYMBOL(inet_frag_queue_insert);
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void *inet_frag_reasm_prepare(struct inet_frag_queue *q, struct sk_buff *skb,
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struct sk_buff *parent)
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{
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struct sk_buff *fp, *head = skb_rb_first(&q->rb_fragments);
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struct sk_buff **nextp;
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int delta;
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if (head != skb) {
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fp = skb_clone(skb, GFP_ATOMIC);
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if (!fp)
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return NULL;
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FRAG_CB(fp)->next_frag = FRAG_CB(skb)->next_frag;
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if (RB_EMPTY_NODE(&skb->rbnode))
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FRAG_CB(parent)->next_frag = fp;
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else
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rb_replace_node(&skb->rbnode, &fp->rbnode,
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&q->rb_fragments);
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if (q->fragments_tail == skb)
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q->fragments_tail = fp;
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skb_morph(skb, head);
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FRAG_CB(skb)->next_frag = FRAG_CB(head)->next_frag;
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rb_replace_node(&head->rbnode, &skb->rbnode,
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&q->rb_fragments);
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consume_skb(head);
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head = skb;
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}
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WARN_ON(head->ip_defrag_offset != 0);
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delta = -head->truesize;
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/* Head of list must not be cloned. */
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if (skb_unclone(head, GFP_ATOMIC))
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return NULL;
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delta += head->truesize;
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if (delta)
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add_frag_mem_limit(q->net, delta);
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/* If the first fragment is fragmented itself, we split
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* it to two chunks: the first with data and paged part
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* and the second, holding only fragments.
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*/
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if (skb_has_frag_list(head)) {
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struct sk_buff *clone;
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int i, plen = 0;
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clone = alloc_skb(0, GFP_ATOMIC);
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if (!clone)
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return NULL;
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skb_shinfo(clone)->frag_list = skb_shinfo(head)->frag_list;
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skb_frag_list_init(head);
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for (i = 0; i < skb_shinfo(head)->nr_frags; i++)
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plen += skb_frag_size(&skb_shinfo(head)->frags[i]);
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clone->data_len = head->data_len - plen;
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clone->len = clone->data_len;
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head->truesize += clone->truesize;
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clone->csum = 0;
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clone->ip_summed = head->ip_summed;
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add_frag_mem_limit(q->net, clone->truesize);
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skb_shinfo(head)->frag_list = clone;
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nextp = &clone->next;
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} else {
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nextp = &skb_shinfo(head)->frag_list;
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}
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return nextp;
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}
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EXPORT_SYMBOL(inet_frag_reasm_prepare);
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void inet_frag_reasm_finish(struct inet_frag_queue *q, struct sk_buff *head,
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void *reasm_data)
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{
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struct sk_buff **nextp = (struct sk_buff **)reasm_data;
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struct rb_node *rbn;
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struct sk_buff *fp;
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skb_push(head, head->data - skb_network_header(head));
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/* Traverse the tree in order, to build frag_list. */
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fp = FRAG_CB(head)->next_frag;
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rbn = rb_next(&head->rbnode);
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rb_erase(&head->rbnode, &q->rb_fragments);
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while (rbn || fp) {
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/* fp points to the next sk_buff in the current run;
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* rbn points to the next run.
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*/
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/* Go through the current run. */
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while (fp) {
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*nextp = fp;
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nextp = &fp->next;
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fp->prev = NULL;
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memset(&fp->rbnode, 0, sizeof(fp->rbnode));
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fp->sk = NULL;
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head->data_len += fp->len;
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head->len += fp->len;
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if (head->ip_summed != fp->ip_summed)
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head->ip_summed = CHECKSUM_NONE;
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else if (head->ip_summed == CHECKSUM_COMPLETE)
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head->csum = csum_add(head->csum, fp->csum);
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head->truesize += fp->truesize;
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fp = FRAG_CB(fp)->next_frag;
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}
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/* Move to the next run. */
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if (rbn) {
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struct rb_node *rbnext = rb_next(rbn);
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fp = rb_to_skb(rbn);
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rb_erase(rbn, &q->rb_fragments);
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rbn = rbnext;
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}
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}
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sub_frag_mem_limit(q->net, head->truesize);
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*nextp = NULL;
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skb_mark_not_on_list(head);
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head->prev = NULL;
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head->tstamp = q->stamp;
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}
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EXPORT_SYMBOL(inet_frag_reasm_finish);
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struct sk_buff *inet_frag_pull_head(struct inet_frag_queue *q)
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{
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struct sk_buff *head;
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if (q->fragments) {
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head = q->fragments;
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q->fragments = head->next;
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} else {
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struct sk_buff *skb;
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head = skb_rb_first(&q->rb_fragments);
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if (!head)
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return NULL;
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skb = FRAG_CB(head)->next_frag;
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if (skb)
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rb_replace_node(&head->rbnode, &skb->rbnode,
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&q->rb_fragments);
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else
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rb_erase(&head->rbnode, &q->rb_fragments);
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memset(&head->rbnode, 0, sizeof(head->rbnode));
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barrier();
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}
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if (head == q->fragments_tail)
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q->fragments_tail = NULL;
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sub_frag_mem_limit(q->net, head->truesize);
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return head;
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}
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EXPORT_SYMBOL(inet_frag_pull_head);
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@ -57,57 +57,6 @@
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*/
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*/
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static const char ip_frag_cache_name[] = "ip4-frags";
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static const char ip_frag_cache_name[] = "ip4-frags";
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/* Use skb->cb to track consecutive/adjacent fragments coming at
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* the end of the queue. Nodes in the rb-tree queue will
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* contain "runs" of one or more adjacent fragments.
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*
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* Invariants:
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* - next_frag is NULL at the tail of a "run";
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* - the head of a "run" has the sum of all fragment lengths in frag_run_len.
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*/
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struct ipfrag_skb_cb {
|
|
||||||
struct inet_skb_parm h;
|
|
||||||
struct sk_buff *next_frag;
|
|
||||||
int frag_run_len;
|
|
||||||
};
|
|
||||||
|
|
||||||
#define FRAG_CB(skb) ((struct ipfrag_skb_cb *)((skb)->cb))
|
|
||||||
|
|
||||||
static void ip4_frag_init_run(struct sk_buff *skb)
|
|
||||||
{
|
|
||||||
BUILD_BUG_ON(sizeof(struct ipfrag_skb_cb) > sizeof(skb->cb));
|
|
||||||
|
|
||||||
FRAG_CB(skb)->next_frag = NULL;
|
|
||||||
FRAG_CB(skb)->frag_run_len = skb->len;
|
|
||||||
}
|
|
||||||
|
|
||||||
/* Append skb to the last "run". */
|
|
||||||
static void ip4_frag_append_to_last_run(struct inet_frag_queue *q,
|
|
||||||
struct sk_buff *skb)
|
|
||||||
{
|
|
||||||
RB_CLEAR_NODE(&skb->rbnode);
|
|
||||||
FRAG_CB(skb)->next_frag = NULL;
|
|
||||||
|
|
||||||
FRAG_CB(q->last_run_head)->frag_run_len += skb->len;
|
|
||||||
FRAG_CB(q->fragments_tail)->next_frag = skb;
|
|
||||||
q->fragments_tail = skb;
|
|
||||||
}
|
|
||||||
|
|
||||||
/* Create a new "run" with the skb. */
|
|
||||||
static void ip4_frag_create_run(struct inet_frag_queue *q, struct sk_buff *skb)
|
|
||||||
{
|
|
||||||
if (q->last_run_head)
|
|
||||||
rb_link_node(&skb->rbnode, &q->last_run_head->rbnode,
|
|
||||||
&q->last_run_head->rbnode.rb_right);
|
|
||||||
else
|
|
||||||
rb_link_node(&skb->rbnode, NULL, &q->rb_fragments.rb_node);
|
|
||||||
rb_insert_color(&skb->rbnode, &q->rb_fragments);
|
|
||||||
|
|
||||||
ip4_frag_init_run(skb);
|
|
||||||
q->fragments_tail = skb;
|
|
||||||
q->last_run_head = skb;
|
|
||||||
}
|
|
||||||
|
|
||||||
/* Describe an entry in the "incomplete datagrams" queue. */
|
/* Describe an entry in the "incomplete datagrams" queue. */
|
||||||
struct ipq {
|
struct ipq {
|
||||||
struct inet_frag_queue q;
|
struct inet_frag_queue q;
|
||||||
@ -212,27 +161,9 @@ static void ip_expire(struct timer_list *t)
|
|||||||
* pull the head out of the tree in order to be able to
|
* pull the head out of the tree in order to be able to
|
||||||
* deal with head->dev.
|
* deal with head->dev.
|
||||||
*/
|
*/
|
||||||
if (qp->q.fragments) {
|
head = inet_frag_pull_head(&qp->q);
|
||||||
head = qp->q.fragments;
|
if (!head)
|
||||||
qp->q.fragments = head->next;
|
goto out;
|
||||||
} else {
|
|
||||||
head = skb_rb_first(&qp->q.rb_fragments);
|
|
||||||
if (!head)
|
|
||||||
goto out;
|
|
||||||
if (FRAG_CB(head)->next_frag)
|
|
||||||
rb_replace_node(&head->rbnode,
|
|
||||||
&FRAG_CB(head)->next_frag->rbnode,
|
|
||||||
&qp->q.rb_fragments);
|
|
||||||
else
|
|
||||||
rb_erase(&head->rbnode, &qp->q.rb_fragments);
|
|
||||||
memset(&head->rbnode, 0, sizeof(head->rbnode));
|
|
||||||
barrier();
|
|
||||||
}
|
|
||||||
if (head == qp->q.fragments_tail)
|
|
||||||
qp->q.fragments_tail = NULL;
|
|
||||||
|
|
||||||
sub_frag_mem_limit(qp->q.net, head->truesize);
|
|
||||||
|
|
||||||
head->dev = dev_get_by_index_rcu(net, qp->iif);
|
head->dev = dev_get_by_index_rcu(net, qp->iif);
|
||||||
if (!head->dev)
|
if (!head->dev)
|
||||||
goto out;
|
goto out;
|
||||||
@ -344,12 +275,10 @@ static int ip_frag_reinit(struct ipq *qp)
|
|||||||
static int ip_frag_queue(struct ipq *qp, struct sk_buff *skb)
|
static int ip_frag_queue(struct ipq *qp, struct sk_buff *skb)
|
||||||
{
|
{
|
||||||
struct net *net = container_of(qp->q.net, struct net, ipv4.frags);
|
struct net *net = container_of(qp->q.net, struct net, ipv4.frags);
|
||||||
struct rb_node **rbn, *parent;
|
int ihl, end, flags, offset;
|
||||||
struct sk_buff *skb1, *prev_tail;
|
struct sk_buff *prev_tail;
|
||||||
int ihl, end, skb1_run_end;
|
|
||||||
struct net_device *dev;
|
struct net_device *dev;
|
||||||
unsigned int fragsize;
|
unsigned int fragsize;
|
||||||
int flags, offset;
|
|
||||||
int err = -ENOENT;
|
int err = -ENOENT;
|
||||||
u8 ecn;
|
u8 ecn;
|
||||||
|
|
||||||
@ -413,62 +342,13 @@ static int ip_frag_queue(struct ipq *qp, struct sk_buff *skb)
|
|||||||
/* Makes sure compiler wont do silly aliasing games */
|
/* Makes sure compiler wont do silly aliasing games */
|
||||||
barrier();
|
barrier();
|
||||||
|
|
||||||
/* RFC5722, Section 4, amended by Errata ID : 3089
|
|
||||||
* When reassembling an IPv6 datagram, if
|
|
||||||
* one or more its constituent fragments is determined to be an
|
|
||||||
* overlapping fragment, the entire datagram (and any constituent
|
|
||||||
* fragments) MUST be silently discarded.
|
|
||||||
*
|
|
||||||
* We do the same here for IPv4 (and increment an snmp counter) but
|
|
||||||
* we do not want to drop the whole queue in response to a duplicate
|
|
||||||
* fragment.
|
|
||||||
*/
|
|
||||||
|
|
||||||
err = -EINVAL;
|
|
||||||
/* Find out where to put this fragment. */
|
|
||||||
prev_tail = qp->q.fragments_tail;
|
prev_tail = qp->q.fragments_tail;
|
||||||
if (!prev_tail)
|
err = inet_frag_queue_insert(&qp->q, skb, offset, end);
|
||||||
ip4_frag_create_run(&qp->q, skb); /* First fragment. */
|
if (err)
|
||||||
else if (prev_tail->ip_defrag_offset + prev_tail->len < end) {
|
goto insert_error;
|
||||||
/* This is the common case: skb goes to the end. */
|
|
||||||
/* Detect and discard overlaps. */
|
|
||||||
if (offset < prev_tail->ip_defrag_offset + prev_tail->len)
|
|
||||||
goto overlap;
|
|
||||||
if (offset == prev_tail->ip_defrag_offset + prev_tail->len)
|
|
||||||
ip4_frag_append_to_last_run(&qp->q, skb);
|
|
||||||
else
|
|
||||||
ip4_frag_create_run(&qp->q, skb);
|
|
||||||
} else {
|
|
||||||
/* Binary search. Note that skb can become the first fragment,
|
|
||||||
* but not the last (covered above).
|
|
||||||
*/
|
|
||||||
rbn = &qp->q.rb_fragments.rb_node;
|
|
||||||
do {
|
|
||||||
parent = *rbn;
|
|
||||||
skb1 = rb_to_skb(parent);
|
|
||||||
skb1_run_end = skb1->ip_defrag_offset +
|
|
||||||
FRAG_CB(skb1)->frag_run_len;
|
|
||||||
if (end <= skb1->ip_defrag_offset)
|
|
||||||
rbn = &parent->rb_left;
|
|
||||||
else if (offset >= skb1_run_end)
|
|
||||||
rbn = &parent->rb_right;
|
|
||||||
else if (offset >= skb1->ip_defrag_offset &&
|
|
||||||
end <= skb1_run_end)
|
|
||||||
goto err; /* No new data, potential duplicate */
|
|
||||||
else
|
|
||||||
goto overlap; /* Found an overlap */
|
|
||||||
} while (*rbn);
|
|
||||||
/* Here we have parent properly set, and rbn pointing to
|
|
||||||
* one of its NULL left/right children. Insert skb.
|
|
||||||
*/
|
|
||||||
ip4_frag_init_run(skb);
|
|
||||||
rb_link_node(&skb->rbnode, parent, rbn);
|
|
||||||
rb_insert_color(&skb->rbnode, &qp->q.rb_fragments);
|
|
||||||
}
|
|
||||||
|
|
||||||
if (dev)
|
if (dev)
|
||||||
qp->iif = dev->ifindex;
|
qp->iif = dev->ifindex;
|
||||||
skb->ip_defrag_offset = offset;
|
|
||||||
|
|
||||||
qp->q.stamp = skb->tstamp;
|
qp->q.stamp = skb->tstamp;
|
||||||
qp->q.meat += skb->len;
|
qp->q.meat += skb->len;
|
||||||
@ -501,10 +381,16 @@ static int ip_frag_queue(struct ipq *qp, struct sk_buff *skb)
|
|||||||
skb_dst_drop(skb);
|
skb_dst_drop(skb);
|
||||||
return -EINPROGRESS;
|
return -EINPROGRESS;
|
||||||
|
|
||||||
overlap:
|
insert_error:
|
||||||
|
if (err == IPFRAG_DUP) {
|
||||||
|
kfree_skb(skb);
|
||||||
|
return -EINVAL;
|
||||||
|
}
|
||||||
|
err = -EINVAL;
|
||||||
__IP_INC_STATS(net, IPSTATS_MIB_REASM_OVERLAPS);
|
__IP_INC_STATS(net, IPSTATS_MIB_REASM_OVERLAPS);
|
||||||
discard_qp:
|
discard_qp:
|
||||||
inet_frag_kill(&qp->q);
|
inet_frag_kill(&qp->q);
|
||||||
|
__IP_INC_STATS(net, IPSTATS_MIB_REASMFAILS);
|
||||||
err:
|
err:
|
||||||
kfree_skb(skb);
|
kfree_skb(skb);
|
||||||
return err;
|
return err;
|
||||||
@ -516,13 +402,8 @@ static int ip_frag_reasm(struct ipq *qp, struct sk_buff *skb,
|
|||||||
{
|
{
|
||||||
struct net *net = container_of(qp->q.net, struct net, ipv4.frags);
|
struct net *net = container_of(qp->q.net, struct net, ipv4.frags);
|
||||||
struct iphdr *iph;
|
struct iphdr *iph;
|
||||||
struct sk_buff *fp, *head = skb_rb_first(&qp->q.rb_fragments);
|
void *reasm_data;
|
||||||
struct sk_buff **nextp; /* To build frag_list. */
|
int len, err;
|
||||||
struct rb_node *rbn;
|
|
||||||
int len;
|
|
||||||
int ihlen;
|
|
||||||
int delta;
|
|
||||||
int err;
|
|
||||||
u8 ecn;
|
u8 ecn;
|
||||||
|
|
||||||
ipq_kill(qp);
|
ipq_kill(qp);
|
||||||
@ -532,117 +413,23 @@ static int ip_frag_reasm(struct ipq *qp, struct sk_buff *skb,
|
|||||||
err = -EINVAL;
|
err = -EINVAL;
|
||||||
goto out_fail;
|
goto out_fail;
|
||||||
}
|
}
|
||||||
|
|
||||||
/* Make the one we just received the head. */
|
/* Make the one we just received the head. */
|
||||||
if (head != skb) {
|
reasm_data = inet_frag_reasm_prepare(&qp->q, skb, prev_tail);
|
||||||
fp = skb_clone(skb, GFP_ATOMIC);
|
if (!reasm_data)
|
||||||
if (!fp)
|
goto out_nomem;
|
||||||
goto out_nomem;
|
|
||||||
FRAG_CB(fp)->next_frag = FRAG_CB(skb)->next_frag;
|
|
||||||
if (RB_EMPTY_NODE(&skb->rbnode))
|
|
||||||
FRAG_CB(prev_tail)->next_frag = fp;
|
|
||||||
else
|
|
||||||
rb_replace_node(&skb->rbnode, &fp->rbnode,
|
|
||||||
&qp->q.rb_fragments);
|
|
||||||
if (qp->q.fragments_tail == skb)
|
|
||||||
qp->q.fragments_tail = fp;
|
|
||||||
skb_morph(skb, head);
|
|
||||||
FRAG_CB(skb)->next_frag = FRAG_CB(head)->next_frag;
|
|
||||||
rb_replace_node(&head->rbnode, &skb->rbnode,
|
|
||||||
&qp->q.rb_fragments);
|
|
||||||
consume_skb(head);
|
|
||||||
head = skb;
|
|
||||||
}
|
|
||||||
|
|
||||||
WARN_ON(head->ip_defrag_offset != 0);
|
|
||||||
|
|
||||||
/* Allocate a new buffer for the datagram. */
|
|
||||||
ihlen = ip_hdrlen(head);
|
|
||||||
len = ihlen + qp->q.len;
|
|
||||||
|
|
||||||
|
len = ip_hdrlen(skb) + qp->q.len;
|
||||||
err = -E2BIG;
|
err = -E2BIG;
|
||||||
if (len > 65535)
|
if (len > 65535)
|
||||||
goto out_oversize;
|
goto out_oversize;
|
||||||
|
|
||||||
delta = - head->truesize;
|
inet_frag_reasm_finish(&qp->q, skb, reasm_data);
|
||||||
|
|
||||||
/* Head of list must not be cloned. */
|
skb->dev = dev;
|
||||||
if (skb_unclone(head, GFP_ATOMIC))
|
IPCB(skb)->frag_max_size = max(qp->max_df_size, qp->q.max_size);
|
||||||
goto out_nomem;
|
|
||||||
|
|
||||||
delta += head->truesize;
|
iph = ip_hdr(skb);
|
||||||
if (delta)
|
|
||||||
add_frag_mem_limit(qp->q.net, delta);
|
|
||||||
|
|
||||||
/* 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_nomem;
|
|
||||||
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 = clone->data_len = head->data_len - plen;
|
|
||||||
head->truesize += clone->truesize;
|
|
||||||
clone->csum = 0;
|
|
||||||
clone->ip_summed = head->ip_summed;
|
|
||||||
add_frag_mem_limit(qp->q.net, clone->truesize);
|
|
||||||
skb_shinfo(head)->frag_list = clone;
|
|
||||||
nextp = &clone->next;
|
|
||||||
} else {
|
|
||||||
nextp = &skb_shinfo(head)->frag_list;
|
|
||||||
}
|
|
||||||
|
|
||||||
skb_push(head, head->data - skb_network_header(head));
|
|
||||||
|
|
||||||
/* Traverse the tree in order, to build frag_list. */
|
|
||||||
fp = FRAG_CB(head)->next_frag;
|
|
||||||
rbn = rb_next(&head->rbnode);
|
|
||||||
rb_erase(&head->rbnode, &qp->q.rb_fragments);
|
|
||||||
while (rbn || fp) {
|
|
||||||
/* fp points to the next sk_buff in the current run;
|
|
||||||
* rbn points to the next run.
|
|
||||||
*/
|
|
||||||
/* Go through the current run. */
|
|
||||||
while (fp) {
|
|
||||||
*nextp = fp;
|
|
||||||
nextp = &fp->next;
|
|
||||||
fp->prev = NULL;
|
|
||||||
memset(&fp->rbnode, 0, sizeof(fp->rbnode));
|
|
||||||
fp->sk = NULL;
|
|
||||||
head->data_len += fp->len;
|
|
||||||
head->len += fp->len;
|
|
||||||
if (head->ip_summed != fp->ip_summed)
|
|
||||||
head->ip_summed = CHECKSUM_NONE;
|
|
||||||
else if (head->ip_summed == CHECKSUM_COMPLETE)
|
|
||||||
head->csum = csum_add(head->csum, fp->csum);
|
|
||||||
head->truesize += fp->truesize;
|
|
||||||
fp = FRAG_CB(fp)->next_frag;
|
|
||||||
}
|
|
||||||
/* Move to the next run. */
|
|
||||||
if (rbn) {
|
|
||||||
struct rb_node *rbnext = rb_next(rbn);
|
|
||||||
|
|
||||||
fp = rb_to_skb(rbn);
|
|
||||||
rb_erase(rbn, &qp->q.rb_fragments);
|
|
||||||
rbn = rbnext;
|
|
||||||
}
|
|
||||||
}
|
|
||||||
sub_frag_mem_limit(qp->q.net, head->truesize);
|
|
||||||
|
|
||||||
*nextp = NULL;
|
|
||||||
skb_mark_not_on_list(head);
|
|
||||||
head->prev = NULL;
|
|
||||||
head->dev = dev;
|
|
||||||
head->tstamp = qp->q.stamp;
|
|
||||||
IPCB(head)->frag_max_size = max(qp->max_df_size, qp->q.max_size);
|
|
||||||
|
|
||||||
iph = ip_hdr(head);
|
|
||||||
iph->tot_len = htons(len);
|
iph->tot_len = htons(len);
|
||||||
iph->tos |= ecn;
|
iph->tos |= ecn;
|
||||||
|
|
||||||
@ -655,7 +442,7 @@ static int ip_frag_reasm(struct ipq *qp, struct sk_buff *skb,
|
|||||||
* from one very small df-fragment and one large non-df frag.
|
* from one very small df-fragment and one large non-df frag.
|
||||||
*/
|
*/
|
||||||
if (qp->max_df_size == qp->q.max_size) {
|
if (qp->max_df_size == qp->q.max_size) {
|
||||||
IPCB(head)->flags |= IPSKB_FRAG_PMTU;
|
IPCB(skb)->flags |= IPSKB_FRAG_PMTU;
|
||||||
iph->frag_off = htons(IP_DF);
|
iph->frag_off = htons(IP_DF);
|
||||||
} else {
|
} else {
|
||||||
iph->frag_off = 0;
|
iph->frag_off = 0;
|
||||||
@ -753,28 +540,6 @@ struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user)
|
|||||||
}
|
}
|
||||||
EXPORT_SYMBOL(ip_check_defrag);
|
EXPORT_SYMBOL(ip_check_defrag);
|
||||||
|
|
||||||
unsigned int inet_frag_rbtree_purge(struct rb_root *root)
|
|
||||||
{
|
|
||||||
struct rb_node *p = rb_first(root);
|
|
||||||
unsigned int sum = 0;
|
|
||||||
|
|
||||||
while (p) {
|
|
||||||
struct sk_buff *skb = rb_entry(p, struct sk_buff, rbnode);
|
|
||||||
|
|
||||||
p = rb_next(p);
|
|
||||||
rb_erase(&skb->rbnode, root);
|
|
||||||
while (skb) {
|
|
||||||
struct sk_buff *next = FRAG_CB(skb)->next_frag;
|
|
||||||
|
|
||||||
sum += skb->truesize;
|
|
||||||
kfree_skb(skb);
|
|
||||||
skb = next;
|
|
||||||
}
|
|
||||||
}
|
|
||||||
return sum;
|
|
||||||
}
|
|
||||||
EXPORT_SYMBOL(inet_frag_rbtree_purge);
|
|
||||||
|
|
||||||
#ifdef CONFIG_SYSCTL
|
#ifdef CONFIG_SYSCTL
|
||||||
static int dist_min;
|
static int dist_min;
|
||||||
|
|
||||||
|
Loading…
Reference in New Issue
Block a user