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-rw-r--r--include/net/inet_frag.h184
1 files changed, 184 insertions, 0 deletions
diff --git a/include/net/inet_frag.h b/include/net/inet_frag.h
new file mode 100644
index 000000000..4cbd413e7
--- /dev/null
+++ b/include/net/inet_frag.h
@@ -0,0 +1,184 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __NET_FRAG_H__
+#define __NET_FRAG_H__
+
+#include <linux/rhashtable-types.h>
+#include <linux/completion.h>
+
+/* Per netns frag queues directory */
+struct fqdir {
+ /* sysctls */
+ long high_thresh;
+ long low_thresh;
+ int timeout;
+ int max_dist;
+ struct inet_frags *f;
+ struct net *net;
+ bool dead;
+
+ struct rhashtable rhashtable ____cacheline_aligned_in_smp;
+
+ /* Keep atomic mem on separate cachelines in structs that include it */
+ atomic_long_t mem ____cacheline_aligned_in_smp;
+ struct work_struct destroy_work;
+};
+
+/**
+ * fragment queue flags
+ *
+ * @INET_FRAG_FIRST_IN: first fragment has arrived
+ * @INET_FRAG_LAST_IN: final fragment has arrived
+ * @INET_FRAG_COMPLETE: frag queue has been processed and is due for destruction
+ * @INET_FRAG_HASH_DEAD: inet_frag_kill() has not removed fq from rhashtable
+ */
+enum {
+ INET_FRAG_FIRST_IN = BIT(0),
+ INET_FRAG_LAST_IN = BIT(1),
+ INET_FRAG_COMPLETE = BIT(2),
+ INET_FRAG_HASH_DEAD = BIT(3),
+};
+
+struct frag_v4_compare_key {
+ __be32 saddr;
+ __be32 daddr;
+ u32 user;
+ u32 vif;
+ __be16 id;
+ u16 protocol;
+};
+
+struct frag_v6_compare_key {
+ struct in6_addr saddr;
+ struct in6_addr daddr;
+ u32 user;
+ __be32 id;
+ u32 iif;
+};
+
+/**
+ * struct inet_frag_queue - fragment queue
+ *
+ * @node: rhash node
+ * @key: keys identifying this frag.
+ * @timer: queue expiration timer
+ * @lock: spinlock protecting this frag
+ * @refcnt: reference count of the queue
+ * @rb_fragments: received fragments rb-tree root
+ * @fragments_tail: received fragments tail
+ * @last_run_head: the head of the last "run". see ip_fragment.c
+ * @stamp: timestamp of the last received fragment
+ * @len: total length of the original datagram
+ * @meat: length of received fragments so far
+ * @flags: fragment queue flags
+ * @max_size: maximum received fragment size
+ * @fqdir: pointer to struct fqdir
+ * @rcu: rcu head for freeing deferall
+ */
+struct inet_frag_queue {
+ struct rhash_head node;
+ union {
+ struct frag_v4_compare_key v4;
+ struct frag_v6_compare_key v6;
+ } key;
+ struct timer_list timer;
+ spinlock_t lock;
+ refcount_t refcnt;
+ struct rb_root rb_fragments;
+ struct sk_buff *fragments_tail;
+ struct sk_buff *last_run_head;
+ ktime_t stamp;
+ int len;
+ int meat;
+ __u8 flags;
+ u16 max_size;
+ struct fqdir *fqdir;
+ struct rcu_head rcu;
+};
+
+struct inet_frags {
+ unsigned int qsize;
+
+ void (*constructor)(struct inet_frag_queue *q,
+ const void *arg);
+ void (*destructor)(struct inet_frag_queue *);
+ void (*frag_expire)(struct timer_list *t);
+ struct kmem_cache *frags_cachep;
+ const char *frags_cache_name;
+ struct rhashtable_params rhash_params;
+ refcount_t refcnt;
+ struct completion completion;
+};
+
+int inet_frags_init(struct inet_frags *);
+void inet_frags_fini(struct inet_frags *);
+
+int fqdir_init(struct fqdir **fqdirp, struct inet_frags *f, struct net *net);
+
+static inline void fqdir_pre_exit(struct fqdir *fqdir)
+{
+ /* Prevent creation of new frags.
+ * Pairs with READ_ONCE() in inet_frag_find().
+ */
+ WRITE_ONCE(fqdir->high_thresh, 0);
+
+ /* Pairs with READ_ONCE() in inet_frag_kill(), ip_expire()
+ * and ip6frag_expire_frag_queue().
+ */
+ WRITE_ONCE(fqdir->dead, true);
+}
+void fqdir_exit(struct fqdir *fqdir);
+
+void inet_frag_kill(struct inet_frag_queue *q);
+void inet_frag_destroy(struct inet_frag_queue *q);
+struct inet_frag_queue *inet_frag_find(struct fqdir *fqdir, void *key);
+
+/* Free all skbs in the queue; return the sum of their truesizes. */
+unsigned int inet_frag_rbtree_purge(struct rb_root *root);
+
+static inline void inet_frag_put(struct inet_frag_queue *q)
+{
+ if (refcount_dec_and_test(&q->refcnt))
+ inet_frag_destroy(q);
+}
+
+/* Memory Tracking Functions. */
+
+static inline long frag_mem_limit(const struct fqdir *fqdir)
+{
+ return atomic_long_read(&fqdir->mem);
+}
+
+static inline void sub_frag_mem_limit(struct fqdir *fqdir, long val)
+{
+ atomic_long_sub(val, &fqdir->mem);
+}
+
+static inline void add_frag_mem_limit(struct fqdir *fqdir, long val)
+{
+ atomic_long_add(val, &fqdir->mem);
+}
+
+/* RFC 3168 support :
+ * We want to check ECN values of all fragments, do detect invalid combinations.
+ * In ipq->ecn, we store the OR value of each ip4_frag_ecn() fragment value.
+ */
+#define IPFRAG_ECN_NOT_ECT 0x01 /* one frag had ECN_NOT_ECT */
+#define IPFRAG_ECN_ECT_1 0x02 /* one frag had ECN_ECT_1 */
+#define IPFRAG_ECN_ECT_0 0x04 /* one frag had ECN_ECT_0 */
+#define IPFRAG_ECN_CE 0x08 /* one frag had ECN_CE */
+
+extern const u8 ip_frag_ecn_table[16];
+
+/* Return values of inet_frag_queue_insert() */
+#define IPFRAG_OK 0
+#define IPFRAG_DUP 1
+#define IPFRAG_OVERLAP 2
+int inet_frag_queue_insert(struct inet_frag_queue *q, struct sk_buff *skb,
+ int offset, int end);
+void *inet_frag_reasm_prepare(struct inet_frag_queue *q, struct sk_buff *skb,
+ struct sk_buff *parent);
+void inet_frag_reasm_finish(struct inet_frag_queue *q, struct sk_buff *head,
+ void *reasm_data, bool try_coalesce);
+struct sk_buff *inet_frag_pull_head(struct inet_frag_queue *q);
+
+#endif