sctp.h

优龙2410linux2.6.8内核源代码

#define sctp_crypto_free_tfm crypto_free_tfm
#define sctp_crypto_hmac crypto_hmac
#else
#define sctp_crypto_alloc_tfm(x...) NULL
#define sctp_crypto_free_tfm(x...)
#define sctp_crypto_hmac(x...)
#endif


/* Map an association to an assoc_id. */
static inline sctp_assoc_t sctp_assoc2id(const struct sctp_association *asoc)
{
	return (asoc?asoc->assoc_id:NULL);
}

/* Look up the association by its id.  */
struct sctp_association *sctp_id2assoc(struct sock *sk, sctp_assoc_t id);


/* A macro to walk a list of skbs.  */
#define sctp_skb_for_each(pos, head, tmp) \
for (pos = (head)->next;\
     tmp = (pos)->next, pos != ((struct sk_buff *)(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);

	list_splice((struct list_head *)list, (struct list_head *)head->prev);

	head->qlen += list->qlen;
	list->qlen = 0;

	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;
}

/* 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));
}

/* Calculate the size (in bytes) occupied by the data of an iovec.  */
static inline size_t get_user_iov_size(struct iovec *iov, int iovlen)
{
	size_t retval = 0;

	for (; iovlen > 0; --iovlen) {
		retval += iov->iov_len;
		iov++;
	}

	return retval;
}

/* 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_opt *sp, int pmtu)
{
	int frag = pmtu;

	frag -= sp->pf->af->net_header_len;
	frag -= sizeof(struct sctphdr) + sizeof(struct sctp_data_chunk);

	if (sp->user_frag)
		frag = min_t(int, frag, sp->user_frag);

	frag = min_t(int, frag, SCTP_MAX_CHUNK_LEN);

	return frag;
}

/* 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), WORD_ROUND(ntohs((chunk)->chunk_hdr.length)), member)

#define _sctp_walk_params(pos, chunk, end, member)\
for (pos.v = chunk->member;\
     pos.v <= (void *)chunk + end - sizeof(sctp_paramhdr_t) &&\
     pos.v <= (void *)chunk + end - WORD_ROUND(ntohs(pos.p->length)); \
     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 - sizeof(sctp_errhdr_t) &&\
     (void *)err <= (void *)chunk_hdr + end - \
		    WORD_ROUND(ntohs(err->length));\
     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 *)kmalloc(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 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(__u16 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));
}

/* WARNING: Do not change the layout of the members in sctp_sock! */
struct sctp_sock {
	struct sock	  sk;
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
	struct ipv6_pinfo *pinet6;
#endif /* CONFIG_IPV6 */
	struct inet_opt	  inet;
	struct sctp_opt	  sctp;
};

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
struct sctp6_sock {
	struct sock	  sk;
	struct ipv6_pinfo *pinet6;
	struct inet_opt	  inet;
	struct sctp_opt	  sctp;
	struct ipv6_pinfo inet6;
};
#endif /* CONFIG_IPV6 */

#define sctp_sk(__sk) (&((struct sctp_sock *)__sk)->sctp)
#define sctp_opt2sk(__sp) &container_of(__sp, struct sctp_sock, sctp)->sk

/* Is a socket of this style? */
#define sctp_style(sk, style) __sctp_style((sk), (SCTP_SOCKET_##style))
int static inline __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))
int static inline __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))
int static inline __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);
}

#endif /* __net_sctp_h__ */