/*	$KAME: keysock.c,v 1.13 2000/03/25 07:24:13 sumikawa Exp $	*/

/*
 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the project nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

/* This code has derived from sys/net/rtsock.c on FreeBSD2.2.5 */

#include <sys/types.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <sys/mbuf.h>
#include <sys/malloc.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/domain.h>
#include <sys/protosw.h>
#include <sys/errno.h>

#include <kern/locks.h>

#include <net/raw_cb.h>
#include <net/route.h>

#include <net/pfkeyv2.h>
#include <netkey/keydb.h>
#include <netkey/key.h>
#include <netkey/keysock.h>
#include <netkey/key_debug.h>

extern lck_mtx_t *raw_mtx;
extern lck_mtx_t *sadb_mutex;
extern void key_init(void);

struct sockaddr key_dst = { 2, PF_KEY, };
struct sockaddr key_src = { 2, PF_KEY, };

static int key_sendup0(struct rawcb *, struct mbuf *, int);

struct pfkeystat pfkeystat;

/*
 * key_output()
 */
int
#ifdef __APPLE__
/* No variable argument support? */
key_output(struct mbuf *m, struct socket *so)
#else
#if __STDC__
key_output(struct mbuf *m, ...)
#else
key_output(m, va_alist)
	struct mbuf *m;
	va_dcl
#endif
#endif
{
	struct sadb_msg *msg;
	int len, error = 0;
#ifndef __APPLE__
	struct socket *so;
	va_list ap;

	va_start(ap, m);
	so = va_arg(ap, struct socket *);
	va_end(ap);
#endif

	if (m == 0)
		panic("key_output: NULL pointer was passed.\n");

	socket_unlock(so, 0);
	lck_mtx_lock(sadb_mutex);
	pfkeystat.out_total++;
	pfkeystat.out_bytes += m->m_pkthdr.len;

	len = m->m_pkthdr.len;
	if (len < sizeof(struct sadb_msg)) {
#if IPSEC_DEBUG
		printf("key_output: Invalid message length.\n");
#endif
		pfkeystat.out_tooshort++;
		error = EINVAL;
		goto end;
	}

	if (m->m_len < sizeof(struct sadb_msg)) {
		if ((m = m_pullup(m, sizeof(struct sadb_msg))) == 0) {
#if IPSEC_DEBUG
			printf("key_output: can't pullup mbuf\n");
#endif
			pfkeystat.out_nomem++;
			error = ENOBUFS;
			goto end;
		}
	}

	if ((m->m_flags & M_PKTHDR) == 0)
		panic("key_output: not M_PKTHDR ??");

#if IPSEC_DEBUG
	KEYDEBUG(KEYDEBUG_KEY_DUMP, kdebug_mbuf(m));
#endif /* defined(IPSEC_DEBUG) */

	msg = mtod(m, struct sadb_msg *);
	pfkeystat.out_msgtype[msg->sadb_msg_type]++;
	if (len != PFKEY_UNUNIT64(msg->sadb_msg_len)) {
#if IPSEC_DEBUG
		printf("key_output: Invalid message length.\n");
#endif
		pfkeystat.out_invlen++;
		error = EINVAL;
		goto end;
	}

	error = key_parse(m, so);
	m = NULL;

end:
	if (m)
		m_freem(m);
	lck_mtx_unlock(sadb_mutex);
	socket_lock(so, 0);
	return error;
}

/*
 * send message to the socket.
 */
static int
key_sendup0(rp, m, promisc)
	struct rawcb *rp;
	struct mbuf *m;
	int promisc;
{
	int error;

	lck_mtx_assert(sadb_mutex, LCK_MTX_ASSERT_OWNED);
	if (promisc) {
		struct sadb_msg *pmsg;

		M_PREPEND(m, sizeof(struct sadb_msg), M_NOWAIT);
		if (m && m->m_len < sizeof(struct sadb_msg))
			m = m_pullup(m, sizeof(struct sadb_msg));
		if (!m) {
#if IPSEC_DEBUG
			printf("key_sendup0: cannot pullup\n");
#endif
			pfkeystat.in_nomem++;
			m_freem(m);
			return ENOBUFS;
		}
		m->m_pkthdr.len += sizeof(*pmsg);

		pmsg = mtod(m, struct sadb_msg *);
		bzero(pmsg, sizeof(*pmsg));
		pmsg->sadb_msg_version = PF_KEY_V2;
		pmsg->sadb_msg_type = SADB_X_PROMISC;
		pmsg->sadb_msg_len = PFKEY_UNIT64(m->m_pkthdr.len);
		/* pid and seq? */

		pfkeystat.in_msgtype[pmsg->sadb_msg_type]++;
	}

	if (!sbappendaddr(&rp->rcb_socket->so_rcv, (struct sockaddr *)&key_src,
	    m, NULL, &error)) {
#if IPSEC_DEBUG
		printf("key_sendup0: sbappendaddr failed\n");
#endif
		pfkeystat.in_nomem++;
	}
	else {
		sorwakeup(rp->rcb_socket);
	}
	return error;
}


/* so can be NULL if target != KEY_SENDUP_ONE */
int
key_sendup_mbuf(so, m, target)
	struct socket *so;
	struct mbuf *m;
	int target;
{
	struct mbuf *n;
	struct keycb *kp;
	int sendup;
	struct rawcb *rp;
	int error = 0;

	lck_mtx_assert(sadb_mutex, LCK_MTX_ASSERT_OWNED);
	if (m == NULL)
		panic("key_sendup_mbuf: NULL pointer was passed.\n");
	if (so == NULL && target == KEY_SENDUP_ONE)
		panic("key_sendup_mbuf: NULL pointer was passed.\n");

	pfkeystat.in_total++;
	pfkeystat.in_bytes += m->m_pkthdr.len;
	if (m->m_len < sizeof(struct sadb_msg)) {
#if 1
		m = m_pullup(m, sizeof(struct sadb_msg));
		if (m == NULL) {
			pfkeystat.in_nomem++;
			return ENOBUFS;
		}
#else
		/* don't bother pulling it up just for stats */
#endif
	}
	if (m->m_len >= sizeof(struct sadb_msg)) {
		struct sadb_msg *msg;
		msg = mtod(m, struct sadb_msg *);
		pfkeystat.in_msgtype[msg->sadb_msg_type]++;
	}
	
	lck_mtx_lock(raw_mtx);
	LIST_FOREACH(rp, &rawcb_list, list)
	{
		if (rp->rcb_proto.sp_family != PF_KEY)
			continue;
		if (rp->rcb_proto.sp_protocol
		 && rp->rcb_proto.sp_protocol != PF_KEY_V2) {
			continue;
		}

		kp = (struct keycb *)rp;
		
		socket_lock(rp->rcb_socket, 1);
		/*
		 * If you are in promiscuous mode, and when you get broadcasted
		 * reply, you'll get two PF_KEY messages.
		 * (based on pf_key@inner.net message on 14 Oct 1998)
		 */
		if (((struct keycb *)rp)->kp_promisc) {
			if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) {
				(void)key_sendup0(rp, n, 1);
				n = NULL;
			}
		}

		/* the exact target will be processed later */
		if (so && sotorawcb(so) == rp) {
			socket_unlock(rp->rcb_socket, 1);
			continue;
		}

		sendup = 0;
		switch (target) {
		case KEY_SENDUP_ONE:
			/* the statement has no effect */
			break;
		case KEY_SENDUP_ALL:
			sendup++;
			break;
		case KEY_SENDUP_REGISTERED:
			if (kp->kp_registered)
				sendup++;
			break;
		}
		pfkeystat.in_msgtarget[target]++;

		if (!sendup) {
			socket_unlock(rp->rcb_socket, 1);
			continue;
		}
		else
			sendup = 0;  // clear for next iteration

		if ((n = m_copy(m, 0, (int)M_COPYALL)) == NULL) {
#if IPSEC_DEBUG
			printf("key_sendup: m_copy fail\n");
#endif
			m_freem(m);
			pfkeystat.in_nomem++;
			socket_unlock(rp->rcb_socket, 1);
			lck_mtx_unlock(raw_mtx);
			return ENOBUFS;
		}

		/*
		 * ignore error even if queue is full.  PF_KEY does not
		 * guarantee the delivery of the message.
		 * this is important when target == KEY_SENDUP_ALL.
		 */
		key_sendup0(rp, n, 0);
		socket_unlock(rp->rcb_socket, 1);
		n = NULL;
	}

	lck_mtx_unlock(raw_mtx);
	if (so) {
		socket_lock(so, 1);
		error = key_sendup0(sotorawcb(so), m, 0);
		socket_unlock(so, 1);
		m = NULL;
	} else {
		error = 0;
		m_freem(m);
	}
	return error;
}

/*
 * key_abort()
 * derived from net/rtsock.c:rts_abort()
 */
static int
key_abort(struct socket *so)
{
	int error;
	error = raw_usrreqs.pru_abort(so);
	return error;
}

/*
 * key_attach()
 * derived from net/rtsock.c:rts_attach()
 */
static int
key_attach(struct socket *so, int proto, struct proc *p)
{
	struct keycb *kp;
	int error;

	if (sotorawcb(so) != 0)
		return EISCONN;	/* XXX panic? */
	kp = (struct keycb *)_MALLOC(sizeof *kp, M_PCB, M_WAITOK); /* XXX */
	if (kp == 0)
		return ENOBUFS;
	bzero(kp, sizeof *kp);

	so->so_pcb = (caddr_t)kp;
	kp->kp_promisc = kp->kp_registered = 0;
	kp->kp_raw.rcb_laddr = &key_src;
	kp->kp_raw.rcb_faddr = &key_dst;

	error = raw_usrreqs.pru_attach(so, proto, p);
	kp = (struct keycb *)sotorawcb(so);
	if (error) {
		_FREE(kp, M_PCB);
		so->so_pcb = (caddr_t) 0;
		so->so_flags |= SOF_PCBCLEARING;
		printf("key_usrreq: key_usrreq results %d\n", error);
		return error;
	}

	/* so is already locked when calling key_attach */
	if (kp->kp_raw.rcb_proto.sp_protocol == PF_KEY) /* XXX: AF_KEY */
		key_cb.key_count++;
	key_cb.any_count++;
	soisconnected(so);
	so->so_options |= SO_USELOOPBACK;

	return 0;
}

/*
 * key_bind()
 * derived from net/rtsock.c:rts_bind()
 */
static int
key_bind(struct socket *so, struct sockaddr *nam, struct proc *p)
{
	int error;
	error = raw_usrreqs.pru_bind(so, nam, p); /* xxx just EINVAL */
	return error;
}

/*
 * key_connect()
 * derived from net/rtsock.c:rts_connect()
 */
static int
key_connect(struct socket *so, struct sockaddr *nam, struct proc *p)
{
	int error;
	error = raw_usrreqs.pru_connect(so, nam, p); /* XXX just EINVAL */
	return error;
}

/*
 * key_detach()
 * derived from net/rtsock.c:rts_detach()
 */
static int
key_detach(struct socket *so)
{
	struct keycb *kp = (struct keycb *)sotorawcb(so);
	int error;

	if (kp != 0) {
		if (kp->kp_raw.rcb_proto.sp_protocol == PF_KEY) /* XXX: AF_KEY */
			key_cb.key_count--;
		key_cb.any_count--;
		socket_unlock(so, 0);
		lck_mtx_lock(sadb_mutex);
		key_freereg(so);
		lck_mtx_unlock(sadb_mutex);
		socket_lock(so, 0);
	}
	error = raw_usrreqs.pru_detach(so);
	return error;
}

/*
 * key_disconnect()
 * derived from net/rtsock.c:key_disconnect()
 */
static int
key_disconnect(struct socket *so)
{
	int error;
	error = raw_usrreqs.pru_disconnect(so);
	return error;
}

/*
 * key_peeraddr()
 * derived from net/rtsock.c:rts_peeraddr()
 */
static int
key_peeraddr(struct socket *so, struct sockaddr **nam)
{
	int error;
	error = raw_usrreqs.pru_peeraddr(so, nam);
	return error;
}

/*
 * key_send()
 * derived from net/rtsock.c:rts_send()
 */
static int
key_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *nam,
	 struct mbuf *control, struct proc *p)
{
	int error;
	error = raw_usrreqs.pru_send(so, flags, m, nam, control, p);
	return error;
}

/*
 * key_shutdown()
 * derived from net/rtsock.c:rts_shutdown()
 */
static int
key_shutdown(struct socket *so)
{
	int error;
	error = raw_usrreqs.pru_shutdown(so);
	return error;
}

/*
 * key_sockaddr()
 * derived from net/rtsock.c:rts_sockaddr()
 */
static int
key_sockaddr(struct socket *so, struct sockaddr **nam)
{
	int error;
	error = raw_usrreqs.pru_sockaddr(so, nam);
	return error;
}

struct pr_usrreqs key_usrreqs = {
	key_abort, pru_accept_notsupp, key_attach, key_bind,
	key_connect,
	pru_connect2_notsupp, pru_control_notsupp, key_detach,
	key_disconnect, pru_listen_notsupp, key_peeraddr,
	pru_rcvd_notsupp,
	pru_rcvoob_notsupp, key_send, pru_sense_null, key_shutdown,
	key_sockaddr, sosend, soreceive, pru_sopoll_notsupp
};

/* sysctl */
SYSCTL_NODE(_net, PF_KEY, key, CTLFLAG_RW, 0, "Key Family");

/*
 * Definitions of protocols supported in the KEY domain.
 */

extern struct domain keydomain;

struct protosw keysw[] = {
{ SOCK_RAW,	&keydomain,	PF_KEY_V2,	PR_ATOMIC|PR_ADDR,
  0,		key_output,	raw_ctlinput,	0,
  0,
  key_init,	0,		0,		0,
  0,
  &key_usrreqs,
  0,		0,		0,
}
};

struct domain keydomain =
    { PF_KEY, "key", key_domain_init, 0, 0,
      keysw, 0,
      0,0,
      sizeof(struct key_cb), 0
    };

DOMAIN_SET(key);