zte's code,first commit

Change-Id: I9a04da59e459a9bc0d67f101f700d9d7dc8d681b
diff --git a/ap/os/linux/linux-3.4.x/include/net/sctp/sctp.h b/ap/os/linux/linux-3.4.x/include/net/sctp/sctp.h
new file mode 100644
index 0000000..43c8bbc
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/include/net/sctp/sctp.h
@@ -0,0 +1,725 @@
+/* SCTP kernel implementation
+ * (C) Copyright IBM Corp. 2001, 2004
+ * Copyright (c) 1999-2000 Cisco, Inc.
+ * Copyright (c) 1999-2001 Motorola, Inc.
+ * Copyright (c) 2001-2003 Intel Corp.
+ *
+ * This file is part of the SCTP kernel implementation
+ *
+ * The base lksctp header.
+ *
+ * This SCTP implementation is free software;
+ * you can redistribute it and/or modify it under the terms of
+ * the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This SCTP implementation is distributed in the hope that it
+ * will be useful, but WITHOUT ANY WARRANTY; without even the implied
+ *                 ************************
+ * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GNU CC; see the file COPYING.  If not, write to
+ * the Free Software Foundation, 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ *
+ * Please send any bug reports or fixes you make to the
+ * email address(es):
+ *    lksctp developers <lksctp-developers@lists.sourceforge.net>
+ *
+ * Or submit a bug report through the following website:
+ *    http://www.sf.net/projects/lksctp
+ *
+ * Written or modified by:
+ *    La Monte H.P. Yarroll <piggy@acm.org>
+ *    Xingang Guo           <xingang.guo@intel.com>
+ *    Jon Grimm             <jgrimm@us.ibm.com>
+ *    Daisy Chang           <daisyc@us.ibm.com>
+ *    Sridhar Samudrala     <sri@us.ibm.com>
+ *    Ardelle Fan           <ardelle.fan@intel.com>
+ *    Ryan Layer            <rmlayer@us.ibm.com>
+ *    Kevin Gao             <kevin.gao@intel.com> 
+ *
+ * Any bugs reported given to us we will try to fix... any fixes shared will
+ * be incorporated into the next SCTP release.
+ */
+
+#ifndef __net_sctp_h__
+#define __net_sctp_h__
+
+/* Header Strategy.
+ *    Start getting some control over the header file depencies:
+ *       includes
+ *       constants
+ *       structs
+ *       prototypes
+ *       macros, externs, and inlines
+ *
+ *   Move test_frame specific items out of the kernel headers
+ *   and into the test frame headers.   This is not perfect in any sense
+ *   and will continue to evolve.
+ */
+
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/in.h>
+#include <linux/tty.h>
+#include <linux/proc_fs.h>
+#include <linux/spinlock.h>
+#include <linux/jiffies.h>
+#include <linux/idr.h>
+
+#if IS_ENABLED(CONFIG_IPV6)
+#include <net/ipv6.h>
+#include <net/ip6_route.h>
+#endif
+
+#include <asm/uaccess.h>
+#include <asm/page.h>
+#include <net/sock.h>
+#include <net/snmp.h>
+#include <net/sctp/structs.h>
+#include <net/sctp/constants.h>
+
+
+/* Set SCTP_DEBUG flag via config if not already set. */
+#ifndef SCTP_DEBUG
+#ifdef CONFIG_SCTP_DBG_MSG
+#define SCTP_DEBUG	1
+#else
+#define SCTP_DEBUG      0
+#endif /* CONFIG_SCTP_DBG */
+#endif /* SCTP_DEBUG */
+
+#ifdef CONFIG_IP_SCTP_MODULE
+#define SCTP_PROTOSW_FLAG 0
+#else /* static! */
+#define SCTP_PROTOSW_FLAG INET_PROTOSW_PERMANENT
+#endif
+
+
+/* Certain internal static functions need to be exported when
+ * compiled into the test frame.
+ */
+#ifndef SCTP_STATIC
+#define SCTP_STATIC static
+#endif
+
+/*
+ * Function declarations.
+ */
+
+/*
+ * sctp/protocol.c
+ */
+extern struct sock *sctp_get_ctl_sock(void);
+extern int sctp_copy_local_addr_list(struct sctp_bind_addr *,
+				     sctp_scope_t, gfp_t gfp,
+				     int flags);
+extern struct sctp_pf *sctp_get_pf_specific(sa_family_t family);
+extern int sctp_register_pf(struct sctp_pf *, sa_family_t);
+extern void sctp_addr_wq_mgmt(struct sctp_sockaddr_entry *, int);
+
+/*
+ * sctp/socket.c
+ */
+int sctp_backlog_rcv(struct sock *sk, struct sk_buff *skb);
+int sctp_inet_listen(struct socket *sock, int backlog);
+void sctp_write_space(struct sock *sk);
+void sctp_data_ready(struct sock *sk, int len);
+unsigned int sctp_poll(struct file *file, struct socket *sock,
+		poll_table *wait);
+void sctp_sock_rfree(struct sk_buff *skb);
+void sctp_copy_sock(struct sock *newsk, struct sock *sk,
+		    struct sctp_association *asoc);
+extern struct percpu_counter sctp_sockets_allocated;
+extern int sctp_asconf_mgmt(struct sctp_sock *, struct sctp_sockaddr_entry *);
+
+/*
+ * sctp/primitive.c
+ */
+int sctp_primitive_ASSOCIATE(struct sctp_association *, void *arg);
+int sctp_primitive_SHUTDOWN(struct sctp_association *, void *arg);
+int sctp_primitive_ABORT(struct sctp_association *, void *arg);
+int sctp_primitive_SEND(struct sctp_association *, void *arg);
+int sctp_primitive_REQUESTHEARTBEAT(struct sctp_association *, void *arg);
+int sctp_primitive_ASCONF(struct sctp_association *, void *arg);
+
+/*
+ * sctp/input.c
+ */
+int sctp_rcv(struct sk_buff *skb);
+void sctp_v4_err(struct sk_buff *skb, u32 info);
+void sctp_hash_established(struct sctp_association *);
+void sctp_unhash_established(struct sctp_association *);
+void sctp_hash_endpoint(struct sctp_endpoint *);
+void sctp_unhash_endpoint(struct sctp_endpoint *);
+struct sock *sctp_err_lookup(int family, struct sk_buff *,
+			     struct sctphdr *, struct sctp_association **,
+			     struct sctp_transport **);
+void sctp_err_finish(struct sock *, struct sctp_association *);
+void sctp_icmp_frag_needed(struct sock *, struct sctp_association *,
+			   struct sctp_transport *t, __u32 pmtu);
+void sctp_icmp_proto_unreachable(struct sock *sk,
+				 struct sctp_association *asoc,
+				 struct sctp_transport *t);
+void sctp_backlog_migrate(struct sctp_association *assoc,
+			  struct sock *oldsk, struct sock *newsk);
+
+/*
+ * sctp/proc.c
+ */
+int sctp_snmp_proc_init(void);
+void sctp_snmp_proc_exit(void);
+int sctp_eps_proc_init(void);
+void sctp_eps_proc_exit(void);
+int sctp_assocs_proc_init(void);
+void sctp_assocs_proc_exit(void);
+int sctp_remaddr_proc_init(void);
+void sctp_remaddr_proc_exit(void);
+
+
+/*
+ * Module global variables
+ */
+
+ /*
+  * sctp/protocol.c
+  */
+extern struct kmem_cache *sctp_chunk_cachep __read_mostly;
+extern struct kmem_cache *sctp_bucket_cachep __read_mostly;
+
+/*
+ *  Section:  Macros, externs, and inlines
+ */
+
+
+#ifdef TEST_FRAME
+#include <test_frame.h>
+#else
+
+/* spin lock wrappers. */
+#define sctp_spin_lock_irqsave(lock, flags) spin_lock_irqsave(lock, flags)
+#define sctp_spin_unlock_irqrestore(lock, flags)  \
+       spin_unlock_irqrestore(lock, flags)
+#define sctp_local_bh_disable() local_bh_disable()
+#define sctp_local_bh_enable()  local_bh_enable()
+#define sctp_spin_lock(lock)    spin_lock(lock)
+#define sctp_spin_unlock(lock)  spin_unlock(lock)
+#define sctp_write_lock(lock)   write_lock(lock)
+#define sctp_write_unlock(lock) write_unlock(lock)
+#define sctp_read_lock(lock)    read_lock(lock)
+#define sctp_read_unlock(lock)  read_unlock(lock)
+
+/* sock lock wrappers. */
+#define sctp_lock_sock(sk)       lock_sock(sk)
+#define sctp_release_sock(sk)    release_sock(sk)
+#define sctp_bh_lock_sock(sk)    bh_lock_sock(sk)
+#define sctp_bh_unlock_sock(sk)  bh_unlock_sock(sk)
+
+/* SCTP SNMP MIB stats handlers */
+DECLARE_SNMP_STAT(struct sctp_mib, sctp_statistics);
+#define SCTP_INC_STATS(field)      SNMP_INC_STATS(sctp_statistics, field)
+#define SCTP_INC_STATS_BH(field)   SNMP_INC_STATS_BH(sctp_statistics, field)
+#define SCTP_INC_STATS_USER(field) SNMP_INC_STATS_USER(sctp_statistics, field)
+#define SCTP_DEC_STATS(field)      SNMP_DEC_STATS(sctp_statistics, field)
+
+#endif /* !TEST_FRAME */
+
+/* sctp mib definitions */
+enum {
+	SCTP_MIB_NUM = 0,
+	SCTP_MIB_CURRESTAB,			/* CurrEstab */
+	SCTP_MIB_ACTIVEESTABS,			/* ActiveEstabs */
+	SCTP_MIB_PASSIVEESTABS,			/* PassiveEstabs */
+	SCTP_MIB_ABORTEDS,			/* Aborteds */
+	SCTP_MIB_SHUTDOWNS,			/* Shutdowns */
+	SCTP_MIB_OUTOFBLUES,			/* OutOfBlues */
+	SCTP_MIB_CHECKSUMERRORS,		/* ChecksumErrors */
+	SCTP_MIB_OUTCTRLCHUNKS,			/* OutCtrlChunks */
+	SCTP_MIB_OUTORDERCHUNKS,		/* OutOrderChunks */
+	SCTP_MIB_OUTUNORDERCHUNKS,		/* OutUnorderChunks */
+	SCTP_MIB_INCTRLCHUNKS,			/* InCtrlChunks */
+	SCTP_MIB_INORDERCHUNKS,			/* InOrderChunks */
+	SCTP_MIB_INUNORDERCHUNKS,		/* InUnorderChunks */
+	SCTP_MIB_FRAGUSRMSGS,			/* FragUsrMsgs */
+	SCTP_MIB_REASMUSRMSGS,			/* ReasmUsrMsgs */
+	SCTP_MIB_OUTSCTPPACKS,			/* OutSCTPPacks */
+	SCTP_MIB_INSCTPPACKS,			/* InSCTPPacks */
+	SCTP_MIB_T1_INIT_EXPIREDS,
+	SCTP_MIB_T1_COOKIE_EXPIREDS,
+	SCTP_MIB_T2_SHUTDOWN_EXPIREDS,
+	SCTP_MIB_T3_RTX_EXPIREDS,
+	SCTP_MIB_T4_RTO_EXPIREDS,
+	SCTP_MIB_T5_SHUTDOWN_GUARD_EXPIREDS,
+	SCTP_MIB_DELAY_SACK_EXPIREDS,
+	SCTP_MIB_AUTOCLOSE_EXPIREDS,
+	SCTP_MIB_T1_RETRANSMITS,
+	SCTP_MIB_T3_RETRANSMITS,
+	SCTP_MIB_PMTUD_RETRANSMITS,
+	SCTP_MIB_FAST_RETRANSMITS,
+	SCTP_MIB_IN_PKT_SOFTIRQ,
+	SCTP_MIB_IN_PKT_BACKLOG,
+	SCTP_MIB_IN_PKT_DISCARDS,
+	SCTP_MIB_IN_DATA_CHUNK_DISCARDS,
+	__SCTP_MIB_MAX
+};
+
+#define SCTP_MIB_MAX    __SCTP_MIB_MAX
+struct sctp_mib {
+        unsigned long   mibs[SCTP_MIB_MAX];
+};
+
+
+/* Print debugging messages.  */
+#if SCTP_DEBUG
+extern int sctp_debug_flag;
+#define SCTP_DEBUG_PRINTK(fmt, args...)			\
+do {							\
+	if (sctp_debug_flag)				\
+		printk(KERN_DEBUG pr_fmt(fmt), ##args);	\
+} while (0)
+#define SCTP_DEBUG_PRINTK_CONT(fmt, args...)		\
+do {							\
+	if (sctp_debug_flag)				\
+		pr_cont(fmt, ##args);			\
+} while (0)
+#define SCTP_DEBUG_PRINTK_IPADDR(fmt_lead, fmt_trail,			\
+				 args_lead, addr, args_trail...)	\
+do {									\
+	const union sctp_addr *_addr = (addr);				\
+	if (sctp_debug_flag) {						\
+		if (_addr->sa.sa_family == AF_INET6) {			\
+			printk(KERN_DEBUG				\
+			       pr_fmt(fmt_lead "%pI6" fmt_trail),	\
+			       args_lead,				\
+			       &_addr->v6.sin6_addr,			\
+			       args_trail);				\
+		} else {						\
+			printk(KERN_DEBUG				\
+			       pr_fmt(fmt_lead "%pI4" fmt_trail),	\
+			       args_lead,				\
+			       &_addr->v4.sin_addr.s_addr,		\
+			       args_trail);				\
+		}							\
+	}								\
+} while (0)
+#define SCTP_ENABLE_DEBUG { sctp_debug_flag = 1; }
+#define SCTP_DISABLE_DEBUG { sctp_debug_flag = 0; }
+
+#define SCTP_ASSERT(expr, str, func) \
+	if (!(expr)) { \
+		SCTP_DEBUG_PRINTK("Assertion Failed: %s(%s) at %s:%s:%d\n", \
+			str, (#expr), __FILE__, __func__, __LINE__); \
+		func; \
+	}
+
+#else	/* SCTP_DEBUG */
+
+#define SCTP_DEBUG_PRINTK(whatever...)
+#define SCTP_DEBUG_PRINTK_CONT(fmt, args...)
+#define SCTP_DEBUG_PRINTK_IPADDR(whatever...)
+#define SCTP_ENABLE_DEBUG
+#define SCTP_DISABLE_DEBUG
+#define SCTP_ASSERT(expr, str, func)
+
+#endif /* SCTP_DEBUG */
+
+
+/*
+ * Macros for keeping a global reference of object allocations.
+ */
+#ifdef CONFIG_SCTP_DBG_OBJCNT
+
+extern atomic_t sctp_dbg_objcnt_sock;
+extern atomic_t sctp_dbg_objcnt_ep;
+extern atomic_t sctp_dbg_objcnt_assoc;
+extern atomic_t sctp_dbg_objcnt_transport;
+extern atomic_t sctp_dbg_objcnt_chunk;
+extern atomic_t sctp_dbg_objcnt_bind_addr;
+extern atomic_t sctp_dbg_objcnt_bind_bucket;
+extern atomic_t sctp_dbg_objcnt_addr;
+extern atomic_t sctp_dbg_objcnt_ssnmap;
+extern atomic_t sctp_dbg_objcnt_datamsg;
+extern atomic_t sctp_dbg_objcnt_keys;
+
+/* Macros to atomically increment/decrement objcnt counters.  */
+#define SCTP_DBG_OBJCNT_INC(name) \
+atomic_inc(&sctp_dbg_objcnt_## name)
+#define SCTP_DBG_OBJCNT_DEC(name) \
+atomic_dec(&sctp_dbg_objcnt_## name)
+#define SCTP_DBG_OBJCNT(name) \
+atomic_t sctp_dbg_objcnt_## name = ATOMIC_INIT(0)
+
+/* Macro to help create new entries in in the global array of
+ * objcnt counters.
+ */
+#define SCTP_DBG_OBJCNT_ENTRY(name) \
+{.label= #name, .counter= &sctp_dbg_objcnt_## name}
+
+void sctp_dbg_objcnt_init(void);
+void sctp_dbg_objcnt_exit(void);
+
+#else
+
+#define SCTP_DBG_OBJCNT_INC(name)
+#define SCTP_DBG_OBJCNT_DEC(name)
+
+static inline void sctp_dbg_objcnt_init(void) { return; }
+static inline void sctp_dbg_objcnt_exit(void) { return; }
+
+#endif /* CONFIG_SCTP_DBG_OBJCOUNT */
+
+#if defined CONFIG_SYSCTL
+void sctp_sysctl_register(void);
+void sctp_sysctl_unregister(void);
+#else
+static inline void sctp_sysctl_register(void) { return; }
+static inline void sctp_sysctl_unregister(void) { return; }
+#endif
+
+/* Size of Supported Address Parameter for 'x' address types. */
+#define SCTP_SAT_LEN(x) (sizeof(struct sctp_paramhdr) + (x) * sizeof(__u16))
+
+#if IS_ENABLED(CONFIG_IPV6)
+
+void sctp_v6_pf_init(void);
+void sctp_v6_pf_exit(void);
+int sctp_v6_protosw_init(void);
+void sctp_v6_protosw_exit(void);
+int sctp_v6_add_protocol(void);
+void sctp_v6_del_protocol(void);
+
+#else /* #ifdef defined(CONFIG_IPV6) */
+
+static inline void sctp_v6_pf_init(void) { return; }
+static inline void sctp_v6_pf_exit(void) { return; }
+static inline int sctp_v6_protosw_init(void) { return 0; }
+static inline void sctp_v6_protosw_exit(void) { return; }
+static inline int sctp_v6_add_protocol(void) { return 0; }
+static inline void sctp_v6_del_protocol(void) { return; }
+
+#endif /* #if defined(CONFIG_IPV6) */
+
+
+/* Map an association to an assoc_id. */
+static inline sctp_assoc_t sctp_assoc2id(const struct sctp_association *asoc)
+{
+	return asoc ? asoc->assoc_id : 0;
+}
+
+/* Look up the association by its id.  */
+struct sctp_association *sctp_id2assoc(struct sock *sk, sctp_assoc_t id);
+
+int sctp_do_peeloff(struct sock *sk, sctp_assoc_t id, struct socket **sockp);
+
+/* A macro to walk a list of skbs.  */
+#define sctp_skb_for_each(pos, head, tmp) \
+	skb_queue_walk_safe(head, pos, tmp)
+
+/* A helper to append an entire skb list (list) to another (head). */
+static inline void sctp_skb_list_tail(struct sk_buff_head *list,
+				      struct sk_buff_head *head)
+{
+	unsigned long flags;
+
+	sctp_spin_lock_irqsave(&head->lock, flags);
+	sctp_spin_lock(&list->lock);
+
+	skb_queue_splice_tail_init(list, head);
+
+	sctp_spin_unlock(&list->lock);
+	sctp_spin_unlock_irqrestore(&head->lock, flags);
+}
+
+/**
+ *	sctp_list_dequeue - remove from the head of the queue
+ *	@list: list to dequeue from
+ *
+ *	Remove the head of the list. The head item is
+ *	returned or %NULL if the list is empty.
+ */
+
+static inline struct list_head *sctp_list_dequeue(struct list_head *list)
+{
+	struct list_head *result = NULL;
+
+	if (list->next != list) {
+		result = list->next;
+		list->next = result->next;
+		list->next->prev = list;
+		INIT_LIST_HEAD(result);
+	}
+	return result;
+}
+
+/* SCTP version of skb_set_owner_r.  We need this one because
+ * of the way we have to do receive buffer accounting on bundled
+ * chunks.
+ */
+static inline void sctp_skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
+{
+	struct sctp_ulpevent *event = sctp_skb2event(skb);
+
+	skb_orphan(skb);
+	skb->sk = sk;
+	skb->destructor = sctp_sock_rfree;
+	atomic_add(event->rmem_len, &sk->sk_rmem_alloc);
+	/*
+	 * This mimics the behavior of skb_set_owner_r
+	 */
+	sk->sk_forward_alloc -= event->rmem_len;
+}
+
+/* Tests if the list has one and only one entry. */
+static inline int sctp_list_single_entry(struct list_head *head)
+{
+	return (head->next != head) && (head->next == head->prev);
+}
+
+/* Generate a random jitter in the range of -50% ~ +50% of input RTO. */
+static inline __s32 sctp_jitter(__u32 rto)
+{
+	static __u32 sctp_rand;
+	__s32 ret;
+
+	/* Avoid divide by zero. */
+	if (!rto)
+		rto = 1;
+
+	sctp_rand += jiffies;
+	sctp_rand ^= (sctp_rand << 12);
+	sctp_rand ^= (sctp_rand >> 20);
+
+	/* Choose random number from 0 to rto, then move to -50% ~ +50%
+	 * of rto.
+	 */
+	ret = sctp_rand % rto - (rto >> 1);
+	return ret;
+}
+
+/* Break down data chunks at this point.  */
+static inline int sctp_frag_point(const struct sctp_association *asoc, int pmtu)
+{
+	struct sctp_sock *sp = sctp_sk(asoc->base.sk);
+	int frag = pmtu;
+
+	frag -= sp->pf->af->net_header_len;
+	frag -= sizeof(struct sctphdr) + sizeof(struct sctp_data_chunk);
+
+	if (asoc->user_frag)
+		frag = min_t(int, frag, asoc->user_frag);
+
+	frag = min_t(int, frag, SCTP_MAX_CHUNK_LEN);
+
+	return frag;
+}
+
+static inline void sctp_assoc_pending_pmtu(struct sctp_association *asoc)
+{
+
+	sctp_assoc_sync_pmtu(asoc);
+	asoc->pmtu_pending = 0;
+}
+
+static inline bool sctp_chunk_pending(const struct sctp_chunk *chunk)
+{
+	return !list_empty(&chunk->list);
+}
+
+/* Walk through a list of TLV parameters.  Don't trust the
+ * individual parameter lengths and instead depend on
+ * the chunk length to indicate when to stop.  Make sure
+ * there is room for a param header too.
+ */
+#define sctp_walk_params(pos, chunk, member)\
+_sctp_walk_params((pos), (chunk), ntohs((chunk)->chunk_hdr.length), member)
+
+#define _sctp_walk_params(pos, chunk, end, member)\
+for (pos.v = chunk->member;\
+     pos.v <= (void *)chunk + end - ntohs(pos.p->length) &&\
+     ntohs(pos.p->length) >= sizeof(sctp_paramhdr_t);\
+     pos.v += WORD_ROUND(ntohs(pos.p->length)))
+
+#define sctp_walk_errors(err, chunk_hdr)\
+_sctp_walk_errors((err), (chunk_hdr), ntohs((chunk_hdr)->length))
+
+#define _sctp_walk_errors(err, chunk_hdr, end)\
+for (err = (sctp_errhdr_t *)((void *)chunk_hdr + \
+	    sizeof(sctp_chunkhdr_t));\
+     (void *)err <= (void *)chunk_hdr + end - ntohs(err->length) &&\
+     ntohs(err->length) >= sizeof(sctp_errhdr_t); \
+     err = (sctp_errhdr_t *)((void *)err + WORD_ROUND(ntohs(err->length))))
+
+#define sctp_walk_fwdtsn(pos, chunk)\
+_sctp_walk_fwdtsn((pos), (chunk), ntohs((chunk)->chunk_hdr->length) - sizeof(struct sctp_fwdtsn_chunk))
+
+#define _sctp_walk_fwdtsn(pos, chunk, end)\
+for (pos = chunk->subh.fwdtsn_hdr->skip;\
+     (void *)pos <= (void *)chunk->subh.fwdtsn_hdr->skip + end - sizeof(struct sctp_fwdtsn_skip);\
+     pos++)
+
+/* Round an int up to the next multiple of 4.  */
+#define WORD_ROUND(s) (((s)+3)&~3)
+
+/* Make a new instance of type.  */
+#define t_new(type, flags)	(type *)kzalloc(sizeof(type), flags)
+
+/* Compare two timevals.  */
+#define tv_lt(s, t) \
+   (s.tv_sec < t.tv_sec || (s.tv_sec == t.tv_sec && s.tv_usec < t.tv_usec))
+
+/* Add tv1 to tv2. */
+#define TIMEVAL_ADD(tv1, tv2) \
+({ \
+        suseconds_t usecs = (tv2).tv_usec + (tv1).tv_usec; \
+        time_t secs = (tv2).tv_sec + (tv1).tv_sec; \
+\
+        if (usecs >= 1000000) { \
+                usecs -= 1000000; \
+                secs++; \
+        } \
+        (tv2).tv_sec = secs; \
+        (tv2).tv_usec = usecs; \
+})
+
+/* External references. */
+
+extern struct proto sctp_prot;
+extern struct proto sctpv6_prot;
+extern struct proc_dir_entry *proc_net_sctp;
+void sctp_put_port(struct sock *sk);
+
+extern struct idr sctp_assocs_id;
+extern spinlock_t sctp_assocs_id_lock;
+
+/* Static inline functions. */
+
+/* Convert from an IP version number to an Address Family symbol.  */
+static inline int ipver2af(__u8 ipver)
+{
+	switch (ipver) {
+	case 4:
+	        return  AF_INET;
+	case 6:
+		return AF_INET6;
+	default:
+		return 0;
+	}
+}
+
+/* Convert from an address parameter type to an address family.  */
+static inline int param_type2af(__be16 type)
+{
+	switch (type) {
+	case SCTP_PARAM_IPV4_ADDRESS:
+	        return  AF_INET;
+	case SCTP_PARAM_IPV6_ADDRESS:
+		return AF_INET6;
+	default:
+		return 0;
+	}
+}
+
+/* Perform some sanity checks. */
+static inline int sctp_sanity_check(void)
+{
+	SCTP_ASSERT(sizeof(struct sctp_ulpevent) <=
+		    sizeof(((struct sk_buff *)0)->cb),
+		    "SCTP: ulpevent does not fit in skb!\n", return 0);
+
+	return 1;
+}
+
+/* Warning: The following hash functions assume a power of two 'size'. */
+/* This is the hash function for the SCTP port hash table. */
+static inline int sctp_phashfn(__u16 lport)
+{
+	return lport & (sctp_port_hashsize - 1);
+}
+
+/* This is the hash function for the endpoint hash table. */
+static inline int sctp_ep_hashfn(__u16 lport)
+{
+	return lport & (sctp_ep_hashsize - 1);
+}
+
+/* This is the hash function for the association hash table. */
+static inline int sctp_assoc_hashfn(__u16 lport, __u16 rport)
+{
+	int h = (lport << 16) + rport;
+	h ^= h>>8;
+	return h & (sctp_assoc_hashsize - 1);
+}
+
+/* This is the hash function for the association hash table.  This is
+ * not used yet, but could be used as a better hash function when
+ * we have a vtag.
+ */
+static inline int sctp_vtag_hashfn(__u16 lport, __u16 rport, __u32 vtag)
+{
+	int h = (lport << 16) + rport;
+	h ^= vtag;
+	return h & (sctp_assoc_hashsize - 1);
+}
+
+#define sctp_for_each_hentry(epb, node, head) \
+	hlist_for_each_entry(epb, node, head, node)
+
+/* Is a socket of this style? */
+#define sctp_style(sk, style) __sctp_style((sk), (SCTP_SOCKET_##style))
+static inline int __sctp_style(const struct sock *sk, sctp_socket_type_t style)
+{
+	return sctp_sk(sk)->type == style;
+}
+
+/* Is the association in this state? */
+#define sctp_state(asoc, state) __sctp_state((asoc), (SCTP_STATE_##state))
+static inline int __sctp_state(const struct sctp_association *asoc,
+			       sctp_state_t state)
+{
+	return asoc->state == state;
+}
+
+/* Is the socket in this state? */
+#define sctp_sstate(sk, state) __sctp_sstate((sk), (SCTP_SS_##state))
+static inline int __sctp_sstate(const struct sock *sk, sctp_sock_state_t state)
+{
+	return sk->sk_state == state;
+}
+
+/* Map v4-mapped v6 address back to v4 address */
+static inline void sctp_v6_map_v4(union sctp_addr *addr)
+{
+	addr->v4.sin_family = AF_INET;
+	addr->v4.sin_port = addr->v6.sin6_port;
+	addr->v4.sin_addr.s_addr = addr->v6.sin6_addr.s6_addr32[3];
+}
+
+/* Map v4 address to v4-mapped v6 address */
+static inline void sctp_v4_map_v6(union sctp_addr *addr)
+{
+	addr->v6.sin6_family = AF_INET6;
+	addr->v6.sin6_port = addr->v4.sin_port;
+	addr->v6.sin6_addr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
+	addr->v6.sin6_addr.s6_addr32[0] = 0;
+	addr->v6.sin6_addr.s6_addr32[1] = 0;
+	addr->v6.sin6_addr.s6_addr32[2] = htonl(0x0000ffff);
+}
+
+/* The cookie is always 0 since this is how it's used in the
+ * pmtu code.
+ */
+static inline struct dst_entry *sctp_transport_dst_check(struct sctp_transport *t)
+{
+	if (t->dst && !dst_check(t->dst, 0)) {
+		dst_release(t->dst);
+		t->dst = NULL;
+	}
+
+	return t->dst;
+}
+
+#endif /* __net_sctp_h__ */