raw.c

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						 "raw sendmsg. Fix it!\n",
						 current->comm);
			err = -EINVAL;
			if (usin->sin_family)
				goto out;
		}
		daddr = usin->sin_addr.s_addr;
		/* ANK: I did not forget to get protocol from port field.
		 * I just do not know, who uses this weirdness.
		 * IP_HDRINCL is much more convenient.
		 */
	} else {
		err = -EINVAL;
		if (sk->state != TCP_ESTABLISHED) 
			goto out;
		daddr = sk->daddr;
	}

	ipc.addr = sk->saddr;
	ipc.opt = NULL;
	ipc.oif = sk->bound_dev_if;

	if (msg->msg_controllen) {
		err = ip_cmsg_send(msg, &ipc);
		if (err)
			goto out;
		if (ipc.opt)
			free = 1;
	}

	rfh.saddr = ipc.addr;
	ipc.addr = daddr;

	if (!ipc.opt)
		ipc.opt = sk->protinfo.af_inet.opt;

	if (ipc.opt) {
		err = -EINVAL;
		/* Linux does not mangle headers on raw sockets,
		 * so that IP options + IP_HDRINCL is non-sense.
		 */
		if (sk->protinfo.af_inet.hdrincl)
			goto done;
		if (ipc.opt->srr) {
			if (!daddr)
				goto done;
			daddr = ipc.opt->faddr;
		}
	}
	tos = RT_TOS(sk->protinfo.af_inet.tos) | sk->localroute;
	if (msg->msg_flags & MSG_DONTROUTE)
		tos |= RTO_ONLINK;

	if (MULTICAST(daddr)) {
		if (!ipc.oif)
			ipc.oif = sk->protinfo.af_inet.mc_index;
		if (!rfh.saddr)
			rfh.saddr = sk->protinfo.af_inet.mc_addr;
	}

	err = ip_route_output(&rt, daddr, rfh.saddr, tos, ipc.oif);

	if (err)
		goto done;

	err = -EACCES;
	if (rt->rt_flags & RTCF_BROADCAST && !sk->broadcast)
		goto done;

	if (msg->msg_flags & MSG_CONFIRM)
		goto do_confirm;
back_from_confirm:

	rfh.iov		= msg->msg_iov;
	rfh.saddr	= rt->rt_src;
	rfh.dst		= &rt->u.dst;
	if (!ipc.addr)
		ipc.addr = rt->rt_dst;
	err = ip_build_xmit(sk, sk->protinfo.af_inet.hdrincl ? raw_getrawfrag :
		       	    raw_getfrag, &rfh, len, &ipc, rt, msg->msg_flags);

done:
	if (free)
		kfree(ipc.opt);
	ip_rt_put(rt);

out:	return err < 0 ? err : len;

do_confirm:
	dst_confirm(&rt->u.dst);
	if (!(msg->msg_flags & MSG_PROBE) || len)
		goto back_from_confirm;
	err = 0;
	goto done;
}

static void raw_close(struct sock *sk, long timeout)
{
        /*
	 * Raw sockets may have direct kernel refereneces. Kill them.
	 */
	ip_ra_control(sk, 0, NULL);

	inet_sock_release(sk);
}

/* This gets rid of all the nasties in af_inet. -DaveM */
static int raw_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
{
	struct sockaddr_in *addr = (struct sockaddr_in *) uaddr;
	int ret = -EINVAL;
	int chk_addr_ret;

	if (sk->state != TCP_CLOSE || addr_len < sizeof(struct sockaddr_in))
		goto out;
	chk_addr_ret = inet_addr_type(addr->sin_addr.s_addr);
	ret = -EADDRNOTAVAIL;
	if (addr->sin_addr.s_addr && chk_addr_ret != RTN_LOCAL &&
	    chk_addr_ret != RTN_MULTICAST && chk_addr_ret != RTN_BROADCAST)
		goto out;
	sk->rcv_saddr = sk->saddr = addr->sin_addr.s_addr;
	if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST)
		sk->saddr = 0;  /* Use device */
	sk_dst_reset(sk);
	ret = 0;
out:	return ret;
}

/*
 *	This should be easy, if there is something there
 *	we return it, otherwise we block.
 */

int raw_recvmsg(struct sock *sk, struct msghdr *msg, int len,
		int noblock, int flags, int *addr_len)
{
	int copied = 0;
	int err = -EOPNOTSUPP;
	struct sockaddr_in *sin = (struct sockaddr_in *)msg->msg_name;
	struct sk_buff *skb;

	if (flags & MSG_OOB)
		goto out;

	if (addr_len)
		*addr_len = sizeof(*sin);

	if (flags & MSG_ERRQUEUE) {
		err = ip_recv_error(sk, msg, len);
		goto out;
	}

	skb = skb_recv_datagram(sk, flags, noblock, &err);
	if (!skb)
		goto out;

	copied = skb->len;
	if (len < copied) {
		msg->msg_flags |= MSG_TRUNC;
		copied = len;
	}

	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
	if (err)
		goto done;

	sock_recv_timestamp(msg, sk, skb);

	/* Copy the address. */
	if (sin) {
		sin->sin_family = AF_INET;
		sin->sin_addr.s_addr = skb->nh.iph->saddr;
		memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
	}
	if (sk->protinfo.af_inet.cmsg_flags)
		ip_cmsg_recv(msg, skb);
done:
	skb_free_datagram(sk, skb);
out:	return err ? : copied;
}

static int raw_init(struct sock *sk)
{
	struct raw_opt *tp = &(sk->tp_pinfo.tp_raw4);
	if (sk->num == IPPROTO_ICMP)
		memset(&tp->filter, 0, sizeof(tp->filter));
	return 0;
}

static int raw_seticmpfilter(struct sock *sk, char *optval, int optlen)
{
	if (optlen > sizeof(struct icmp_filter))
		optlen = sizeof(struct icmp_filter);
	if (copy_from_user(&sk->tp_pinfo.tp_raw4.filter, optval, optlen))
		return -EFAULT;
	return 0;
}

static int raw_geticmpfilter(struct sock *sk, char *optval, int *optlen)
{
	int len, ret = -EFAULT;

	if (get_user(len, optlen))
		goto out;
	ret = -EINVAL;
	if (len < 0)
		goto out;
	if (len > sizeof(struct icmp_filter))
		len = sizeof(struct icmp_filter);
	ret = -EFAULT;
	if (put_user(len, optlen) ||
	    copy_to_user(optval, &sk->tp_pinfo.tp_raw4.filter, len))
		goto out;
	ret = 0;
out:	return ret;
}

static int raw_setsockopt(struct sock *sk, int level, int optname, 
			  char *optval, int optlen)
{
	if (level != SOL_RAW)
		return ip_setsockopt(sk, level, optname, optval, optlen);

	if (optname == ICMP_FILTER) {
		if (sk->num != IPPROTO_ICMP)
			return -EOPNOTSUPP;
		else
			return raw_seticmpfilter(sk, optval, optlen);
	}
	return -ENOPROTOOPT;
}

static int raw_getsockopt(struct sock *sk, int level, int optname, 
			  char *optval, int *optlen)
{
	if (level != SOL_RAW)
		return ip_getsockopt(sk, level, optname, optval, optlen);

	if (optname == ICMP_FILTER) {
		if (sk->num != IPPROTO_ICMP)
			return -EOPNOTSUPP;
		else
			return raw_geticmpfilter(sk, optval, optlen);
	}
	return -ENOPROTOOPT;
}

static int raw_ioctl(struct sock *sk, int cmd, unsigned long arg)
{
	switch (cmd) {
		case SIOCOUTQ: {
			int amount = atomic_read(&sk->wmem_alloc);
			return put_user(amount, (int *)arg);
		}
		case SIOCINQ: {
			struct sk_buff *skb;
			int amount = 0;

			spin_lock_irq(&sk->receive_queue.lock);
			skb = skb_peek(&sk->receive_queue);
			if (skb != NULL)
				amount = skb->len;
			spin_unlock_irq(&sk->receive_queue.lock);
			return put_user(amount, (int *)arg);
		}

		default:
#ifdef CONFIG_IP_MROUTE
			return ipmr_ioctl(sk, cmd, arg);
#else
			return -ENOIOCTLCMD;
#endif
	}
}

static void get_raw_sock(struct sock *sp, char *tmpbuf, int i)
{
	unsigned int dest = sp->daddr,
		     src = sp->rcv_saddr;
	__u16 destp = 0,
	      srcp  = sp->num;

	sprintf(tmpbuf, "%4d: %08X:%04X %08X:%04X"
		" %02X %08X:%08X %02X:%08lX %08X %5d %8d %ld %d %p",
		i, src, srcp, dest, destp, sp->state, 
		atomic_read(&sp->wmem_alloc), atomic_read(&sp->rmem_alloc),
		0, 0L, 0,
		sock_i_uid(sp), 0,
		sock_i_ino(sp),
		atomic_read(&sp->refcnt), sp);
}

int raw_get_info(char *buffer, char **start, off_t offset, int length)
{
	int len = 0, num = 0, i;
	off_t pos = 128;
	off_t begin;
	char tmpbuf[129];

	if (offset < 128) 
		len += sprintf(buffer, "%-127s\n",
			       "  sl  local_address rem_address   st tx_queue "
			       "rx_queue tr tm->when retrnsmt   uid  timeout "
			       "inode");
	read_lock(&raw_v4_lock);
	for (i = 0; i < RAWV4_HTABLE_SIZE; i++) {
		struct sock *sk;

		for (sk = raw_v4_htable[i]; sk; sk = sk->next, num++) {
			if (sk->family != PF_INET)
				continue;
			pos += 128;
			if (pos <= offset)
				continue;
			get_raw_sock(sk, tmpbuf, i);
			len += sprintf(buffer + len, "%-127s\n", tmpbuf);
			if (len >= length)
				goto out;
		}
	}
out:
	read_unlock(&raw_v4_lock);
	begin = len - (pos - offset);
	*start = buffer + begin;
	len -= begin;
	if (len > length)
		len = length;
	if (len < 0)
		len = 0; 
	return len;
}

struct proto raw_prot = {
	name:		"RAW",
	close:		raw_close,
	connect:	udp_connect,
	disconnect:	udp_disconnect,
	ioctl:		raw_ioctl,
	init:		raw_init,
	setsockopt:	raw_setsockopt,
	getsockopt:	raw_getsockopt,
	sendmsg:	raw_sendmsg,
	recvmsg:	raw_recvmsg,
	bind:		raw_bind,
	backlog_rcv:	raw_rcv_skb,
	hash:		raw_v4_hash,
	unhash:		raw_v4_unhash,
};