protocol.c

Linux Kernel 2.6.9 for OMAP1710

	} else if (IS_IPV4_LINK_ADDRESS(&addr->v4.sin_addr.s_addr)) {
		retval = SCTP_SCOPE_LINK;
	} else if (IS_IPV4_PRIVATE_ADDRESS(&addr->v4.sin_addr.s_addr)) {
		retval = SCTP_SCOPE_PRIVATE;
	} else {
		retval = SCTP_SCOPE_GLOBAL;
	}

	return retval;
}

/* Returns a valid dst cache entry for the given source and destination ip
 * addresses. If an association is passed, trys to get a dst entry with a
 * source address that matches an address in the bind address list.
 */
struct dst_entry *sctp_v4_get_dst(struct sctp_association *asoc,
				  union sctp_addr *daddr,
				  union sctp_addr *saddr)
{
	struct rtable *rt;
	struct flowi fl;
	struct sctp_bind_addr *bp;
	rwlock_t *addr_lock;
	struct sctp_sockaddr_entry *laddr;
	struct list_head *pos;
	struct dst_entry *dst = NULL;
	union sctp_addr dst_saddr;

	memset(&fl, 0x0, sizeof(struct flowi));
	fl.fl4_dst  = daddr->v4.sin_addr.s_addr;
	fl.proto = IPPROTO_SCTP;
	if (asoc) {
		fl.fl4_tos = RT_CONN_FLAGS(asoc->base.sk);
		fl.oif = asoc->base.sk->sk_bound_dev_if;
	}
	if (saddr)
		fl.fl4_src = saddr->v4.sin_addr.s_addr;

	SCTP_DEBUG_PRINTK("%s: DST:%u.%u.%u.%u, SRC:%u.%u.%u.%u - ",
			  __FUNCTION__, NIPQUAD(fl.fl4_dst),
			  NIPQUAD(fl.fl4_src));

	if (!ip_route_output_key(&rt, &fl)) {
		dst = &rt->u.dst;
	}

	/* If there is no association or if a source address is passed, no
	 * more validation is required.
	 */
	if (!asoc || saddr)
		goto out;

	bp = &asoc->base.bind_addr;
	addr_lock = &asoc->base.addr_lock;

	if (dst) {
		/* Walk through the bind address list and look for a bind
		 * address that matches the source address of the returned dst.
		 */
		sctp_read_lock(addr_lock);
		list_for_each(pos, &bp->address_list) {
			laddr = list_entry(pos, struct sctp_sockaddr_entry,
					   list);
			sctp_v4_dst_saddr(&dst_saddr, dst, bp->port);
			if (sctp_v4_cmp_addr(&dst_saddr, &laddr->a))
				goto out_unlock;
		}
		sctp_read_unlock(addr_lock);

		/* None of the bound addresses match the source address of the
		 * dst. So release it.
		 */
		dst_release(dst);
		dst = NULL;
	}

	/* Walk through the bind address list and try to get a dst that
	 * matches a bind address as the source address.
	 */
	sctp_read_lock(addr_lock);
	list_for_each(pos, &bp->address_list) {
		laddr = list_entry(pos, struct sctp_sockaddr_entry, list);

		if (AF_INET == laddr->a.sa.sa_family) {
			fl.fl4_src = laddr->a.v4.sin_addr.s_addr;
			if (!ip_route_output_key(&rt, &fl)) {
				dst = &rt->u.dst;
				goto out_unlock;
			}
		}
	}

out_unlock:
	sctp_read_unlock(addr_lock);
out:
	if (dst)
		SCTP_DEBUG_PRINTK("rt_dst:%u.%u.%u.%u, rt_src:%u.%u.%u.%u\n",
			  	  NIPQUAD(rt->rt_dst), NIPQUAD(rt->rt_src));
	else
		SCTP_DEBUG_PRINTK("NO ROUTE\n");

	return dst;
}

/* For v4, the source address is cached in the route entry(dst). So no need
 * to cache it separately and hence this is an empty routine.
 */
void sctp_v4_get_saddr(struct sctp_association *asoc,
		       struct dst_entry *dst,
		       union sctp_addr *daddr,
		       union sctp_addr *saddr)
{
	struct rtable *rt = (struct rtable *)dst;

	if (rt) {
		saddr->v4.sin_family = AF_INET;
		saddr->v4.sin_port = asoc->base.bind_addr.port;  
		saddr->v4.sin_addr.s_addr = rt->rt_src; 
	}
}

/* What interface did this skb arrive on? */
static int sctp_v4_skb_iif(const struct sk_buff *skb)
{
     	return ((struct rtable *)skb->dst)->rt_iif;
}

/* Was this packet marked by Explicit Congestion Notification? */
static int sctp_v4_is_ce(const struct sk_buff *skb)
{
	return INET_ECN_is_ce(skb->nh.iph->tos);
}

/* Create and initialize a new sk for the socket returned by accept(). */
struct sock *sctp_v4_create_accept_sk(struct sock *sk,
				      struct sctp_association *asoc)
{
	struct sock *newsk;
	struct inet_opt *inet = inet_sk(sk);
	struct inet_opt *newinet;

	newsk = sk_alloc(PF_INET, GFP_KERNEL, sk->sk_prot->slab_obj_size,
			 sk->sk_prot->slab);
	if (!newsk)
		goto out;

	sock_init_data(NULL, newsk);
	sk_set_owner(newsk, THIS_MODULE);

	newsk->sk_type = SOCK_STREAM;

	newsk->sk_prot = sk->sk_prot;
	newsk->sk_no_check = sk->sk_no_check;
	newsk->sk_reuse = sk->sk_reuse;
	newsk->sk_shutdown = sk->sk_shutdown;

	newsk->sk_destruct = inet_sock_destruct;
	newsk->sk_zapped = 0;
	newsk->sk_family = PF_INET;
	newsk->sk_protocol = IPPROTO_SCTP;
	newsk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;

	newinet = inet_sk(newsk);

	/* Initialize sk's sport, dport, rcv_saddr and daddr for
	 * getsockname() and getpeername()
	 */
	newinet->sport = inet->sport;
	newinet->saddr = inet->saddr;
	newinet->rcv_saddr = inet->rcv_saddr;
	newinet->dport = htons(asoc->peer.port);
	newinet->daddr = asoc->peer.primary_addr.v4.sin_addr.s_addr;
	newinet->pmtudisc = inet->pmtudisc;
      	newinet->id = 0;

	newinet->uc_ttl = -1;
	newinet->mc_loop = 1;
	newinet->mc_ttl = 1;
	newinet->mc_index = 0;
	newinet->mc_list = NULL;

#ifdef INET_REFCNT_DEBUG
	atomic_inc(&inet_sock_nr);
#endif

	if (newsk->sk_prot->init(newsk)) {
		sk_common_release(newsk);
		newsk = NULL;
	}

out:
	return newsk;
}

/* Map address, empty for v4 family */
static void sctp_v4_addr_v4map(struct sctp_opt *sp, union sctp_addr *addr)
{
	/* Empty */
}

/* Dump the v4 addr to the seq file. */
static void sctp_v4_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
{
	seq_printf(seq, "%d.%d.%d.%d ", NIPQUAD(addr->v4.sin_addr));
}

/* Event handler for inet address addition/deletion events.
 * Basically, whenever there is an event, we re-build our local address list.
 */
static int sctp_inetaddr_event(struct notifier_block *this, unsigned long ev,
			       void *ptr)
{
	unsigned long flags;

	sctp_spin_lock_irqsave(&sctp_local_addr_lock, flags);
	__sctp_free_local_addr_list();
	__sctp_get_local_addr_list();
	sctp_spin_unlock_irqrestore(&sctp_local_addr_lock, flags);

	return NOTIFY_DONE;
}

/*
 * Initialize the control inode/socket with a control endpoint data
 * structure.  This endpoint is reserved exclusively for the OOTB processing.
 */
int sctp_ctl_sock_init(void)
{
	int err;
	sa_family_t family;

	if (sctp_get_pf_specific(PF_INET6))
		family = PF_INET6;
	else
		family = PF_INET;

	err = sock_create_kern(family, SOCK_SEQPACKET, IPPROTO_SCTP,
			       &sctp_ctl_socket);
	if (err < 0) {
		printk(KERN_ERR
		       "SCTP: Failed to create the SCTP control socket.\n");
		return err;
	}
	sctp_ctl_socket->sk->sk_allocation = GFP_ATOMIC;
	inet_sk(sctp_ctl_socket->sk)->uc_ttl = -1;

	return 0;
}

/* Register address family specific functions. */
int sctp_register_af(struct sctp_af *af)
{
	switch (af->sa_family) {
	case AF_INET:
		if (sctp_af_v4_specific)
			return 0;
		sctp_af_v4_specific = af;
		break;
	case AF_INET6:
		if (sctp_af_v6_specific)
			return 0;
		sctp_af_v6_specific = af;
		break;
	default:
		return 0;
	}

	INIT_LIST_HEAD(&af->list);
	list_add_tail(&af->list, &sctp_address_families);
	return 1;
}

/* Get the table of functions for manipulating a particular address
 * family.
 */
struct sctp_af *sctp_get_af_specific(sa_family_t family)
{
	switch (family) {
	case AF_INET:
		return sctp_af_v4_specific;
	case AF_INET6:
		return sctp_af_v6_specific;
	default:
		return NULL;
	}
}

/* Common code to initialize a AF_INET msg_name. */
static void sctp_inet_msgname(char *msgname, int *addr_len)
{
	struct sockaddr_in *sin;

	sin = (struct sockaddr_in *)msgname;
	*addr_len = sizeof(struct sockaddr_in);
	sin->sin_family = AF_INET;
	memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
}

/* Copy the primary address of the peer primary address as the msg_name. */
static void sctp_inet_event_msgname(struct sctp_ulpevent *event, char *msgname,
				    int *addr_len)
{
	struct sockaddr_in *sin, *sinfrom;

	if (msgname) {
		struct sctp_association *asoc;

		asoc = event->asoc;
		sctp_inet_msgname(msgname, addr_len);
		sin = (struct sockaddr_in *)msgname;
		sinfrom = &asoc->peer.primary_addr.v4;
		sin->sin_port = htons(asoc->peer.port);
		sin->sin_addr.s_addr = sinfrom->sin_addr.s_addr;
	}
}

/* Initialize and copy out a msgname from an inbound skb. */
static void sctp_inet_skb_msgname(struct sk_buff *skb, char *msgname, int *len)
{
	struct sctphdr *sh;
	struct sockaddr_in *sin;

	if (msgname) {
		sctp_inet_msgname(msgname, len);
		sin = (struct sockaddr_in *)msgname;
		sh = (struct sctphdr *)skb->h.raw;
		sin->sin_port = sh->source;
		sin->sin_addr.s_addr = skb->nh.iph->saddr;
	}
}

/* Do we support this AF? */
static int sctp_inet_af_supported(sa_family_t family, struct sctp_opt *sp)
{
	/* PF_INET only supports AF_INET addresses. */
	return (AF_INET == family);
}

/* Address matching with wildcards allowed. */
static int sctp_inet_cmp_addr(const union sctp_addr *addr1,
			      const union sctp_addr *addr2,
			      struct sctp_opt *opt)
{
	/* PF_INET only supports AF_INET addresses. */
	if (addr1->sa.sa_family != addr2->sa.sa_family)
		return 0;
	if (INADDR_ANY == addr1->v4.sin_addr.s_addr ||
	    INADDR_ANY == addr2->v4.sin_addr.s_addr)
		return 1;
	if (addr1->v4.sin_addr.s_addr == addr2->v4.sin_addr.s_addr)
		return 1;

	return 0;
}

/* Verify that provided sockaddr looks bindable.  Common verification has
 * already been taken care of.
 */
static int sctp_inet_bind_verify(struct sctp_opt *opt, union sctp_addr *addr)
{
	return sctp_v4_available(addr, opt);
}

/* Verify that sockaddr looks sendable.  Common verification has already
 * been taken care of.
 */
static int sctp_inet_send_verify(struct sctp_opt *opt, union sctp_addr *addr)
{
	return 1;
}

/* Fill in Supported Address Type information for INIT and INIT-ACK
 * chunks.  Returns number of addresses supported.
 */
static int sctp_inet_supported_addrs(const struct sctp_opt *opt,
				     __u16 *types)
{
	types[0] = SCTP_PARAM_IPV4_ADDRESS;
	return 1;
}

/* Wrapper routine that calls the ip transmit routine. */
static inline int sctp_v4_xmit(struct sk_buff *skb,
			       struct sctp_transport *transport, int ipfragok)
{
	SCTP_DEBUG_PRINTK("%s: skb:%p, len:%d, "
			  "src:%u.%u.%u.%u, dst:%u.%u.%u.%u\n",
			  __FUNCTION__, skb, skb->len,
			  NIPQUAD(((struct rtable *)skb->dst)->rt_src),
			  NIPQUAD(((struct rtable *)skb->dst)->rt_dst));

	SCTP_INC_STATS(SCTP_MIB_OUTSCTPPACKS);
	return ip_queue_xmit(skb, ipfragok);
}

struct sctp_af sctp_ipv4_specific;

static struct sctp_pf sctp_pf_inet = {
	.event_msgname = sctp_inet_event_msgname,
	.skb_msgname   = sctp_inet_skb_msgname,
	.af_supported  = sctp_inet_af_supported,
	.cmp_addr      = sctp_inet_cmp_addr,
	.bind_verify   = sctp_inet_bind_verify,
	.send_verify   = sctp_inet_send_verify,
	.supported_addrs = sctp_inet_supported_addrs,
	.create_accept_sk = sctp_v4_create_accept_sk,
	.addr_v4map	= sctp_v4_addr_v4map,
	.af            = &sctp_ipv4_specific,
};

/* Notifier for inetaddr addition/deletion events.  */
struct notifier_block sctp_inetaddr_notifier = {
	.notifier_call = sctp_inetaddr_event,
};