/*      $NetBSD: l2cap_socket.c,v 1.37 2024/07/05 04:31:53 rin Exp $    */

/*-
 * Copyright (c) 2005 Iain Hibbert.
 * Copyright (c) 2006 Itronix Inc.
 * 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. The name of Itronix Inc. may not be used to endorse
 *    or promote products derived from this software without specific
 *    prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY ITRONIX INC. ``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 ITRONIX INC. 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.
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: l2cap_socket.c,v 1.37 2024/07/05 04:31:53 rin Exp $");

/* load symbolic names */
#ifdef BLUETOOTH_DEBUG
#define PRUREQUESTS
#define PRCOREQUESTS
#endif

#include <sys/param.h>
#include <sys/domain.h>
#include <sys/kernel.h>
#include <sys/mbuf.h>
#include <sys/proc.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/systm.h>

#include <netbt/bluetooth.h>
#include <netbt/l2cap.h>

/*
 * L2CAP Sockets
 *
 *      SOCK_SEQPACKET - normal L2CAP connection
 *
 *      SOCK_DGRAM - connectionless L2CAP - XXX not yet
 */

static void l2cap_connecting(void *);
static void l2cap_connected(void *);
static void l2cap_disconnected(void *, int);
static void *l2cap_newconn(void *, struct sockaddr_bt *, struct sockaddr_bt *);
static void l2cap_complete(void *, int);
static void l2cap_linkmode(void *, int);
static void l2cap_input(void *, struct mbuf *);

static const struct btproto l2cap_proto = {
        l2cap_connecting,
        l2cap_connected,
        l2cap_disconnected,
        l2cap_newconn,
        l2cap_complete,
        l2cap_linkmode,
        l2cap_input,
};

/* sysctl variables */
int l2cap_sendspace = 4096;
int l2cap_recvspace = 4096;

static int
l2cap_attach(struct socket *so, int proto)
{
        int error;

        KASSERT(so->so_pcb == NULL);

        if (so->so_lock == NULL) {
                mutex_obj_hold(bt_lock);
                so->so_lock = bt_lock;
                solock(so);
        }
        KASSERT(solocked(so));

        /*
         * For L2CAP socket PCB we just use an l2cap_channel structure
         * since we have nothing to add..
         */
        error = soreserve(so, l2cap_sendspace, l2cap_recvspace);
        if (error)
                return error;

        return l2cap_attach_pcb((struct l2cap_channel **)&so->so_pcb,
                                &l2cap_proto, so);
}

static void
l2cap_detach(struct socket *so)
{
        KASSERT(so->so_pcb != NULL);
        l2cap_detach_pcb((struct l2cap_channel **)&so->so_pcb);
        KASSERT(so->so_pcb == NULL);
}

static int
l2cap_accept(struct socket *so, struct sockaddr *nam)
{
        struct l2cap_channel *pcb = so->so_pcb;

        KASSERT(solocked(so));
        KASSERT(nam != NULL);

        if (pcb == NULL)
                return EINVAL;

        return l2cap_peeraddr_pcb(pcb, (struct sockaddr_bt *)nam);
}

static int
l2cap_bind(struct socket *so, struct sockaddr *nam, struct lwp *l)
{
        struct l2cap_channel *pcb = so->so_pcb;
        struct sockaddr_bt *sa = (struct sockaddr_bt *)nam;

        KASSERT(solocked(so));
        KASSERT(nam != NULL);

        if (pcb == NULL)
                return EINVAL;

        if (sa->bt_len != sizeof(struct sockaddr_bt))
                return EINVAL;

        if (sa->bt_family != AF_BLUETOOTH)
                return EAFNOSUPPORT;

        return l2cap_bind_pcb(pcb, sa);
}

static int
l2cap_listen(struct socket *so, struct lwp *l)
{
        struct l2cap_channel *pcb = so->so_pcb;

        KASSERT(solocked(so));

        if (pcb == NULL)
                return EINVAL;

        return l2cap_listen_pcb(pcb);
}

static int
l2cap_connect(struct socket *so, struct sockaddr *nam, struct lwp *l)
{
        struct l2cap_channel *pcb = so->so_pcb;
        struct sockaddr_bt *sa = (struct sockaddr_bt *)nam;

        KASSERT(solocked(so));
        KASSERT(nam != NULL);

        if (pcb == NULL)
                return EINVAL;

        if (sa->bt_len != sizeof(struct sockaddr_bt))
                return EINVAL;

        if (sa->bt_family != AF_BLUETOOTH)
                return EAFNOSUPPORT;

        soisconnecting(so);
        return l2cap_connect_pcb(pcb, sa);
}

static int
l2cap_connect2(struct socket *so, struct socket *so2)
{
        KASSERT(solocked(so));

        if (so->so_pcb == NULL)
                return EINVAL;

        return EOPNOTSUPP;
}

static int
l2cap_disconnect(struct socket *so)
{
        struct l2cap_channel *pcb = so->so_pcb;

        KASSERT(solocked(so));

        if (pcb == NULL)
                return EINVAL;

        soisdisconnecting(so);
        return l2cap_disconnect_pcb(pcb, so->so_linger);
}

static int
l2cap_shutdown(struct socket *so)
{
        KASSERT(solocked(so));

        socantsendmore(so);
        return 0;
}

static int
l2cap_abort(struct socket *so)
{
        struct l2cap_channel *pcb = so->so_pcb;

        KASSERT(solocked(so));

        if (pcb == NULL)
                return EINVAL;

        l2cap_disconnect_pcb(pcb, 0);
        soisdisconnected(so);
        l2cap_detach(so);
        return 0;
}

static int
l2cap_ioctl(struct socket *so, u_long cmd, void *nam, struct ifnet *ifp)
{
        return EPASSTHROUGH;
}

static int
l2cap_stat(struct socket *so, struct stat *ub)
{
        KASSERT(solocked(so));

        return 0;
}

static int
l2cap_peeraddr(struct socket *so, struct sockaddr *nam)
{
        struct l2cap_channel *pcb = so->so_pcb;

        KASSERT(solocked(so));
        KASSERT(pcb != NULL);
        KASSERT(nam != NULL);

        return l2cap_peeraddr_pcb(pcb, (struct sockaddr_bt *)nam);
}

static int
l2cap_sockaddr(struct socket *so, struct sockaddr *nam)
{
        struct l2cap_channel *pcb = so->so_pcb;

        KASSERT(solocked(so));
        KASSERT(pcb != NULL);
        KASSERT(nam != NULL);

        return l2cap_sockaddr_pcb(pcb, (struct sockaddr_bt *)nam);
}

static int
l2cap_rcvd(struct socket *so, int flags, struct lwp *l)
{
        KASSERT(solocked(so));

        return EOPNOTSUPP;
}

static int
l2cap_recvoob(struct socket *so, struct mbuf *m, int flags)
{
        KASSERT(solocked(so));

        return EOPNOTSUPP;
}

static int
l2cap_send(struct socket *so, struct mbuf *m, struct sockaddr *nam,
    struct mbuf *control, struct lwp *l)
{
        struct l2cap_channel *pcb = so->so_pcb;
        struct mbuf *m0;
        int error = 0;

        KASSERT(solocked(so));
        KASSERT(m != NULL);

        m_freem(control);

        if (pcb == NULL) {
                error = EINVAL;
                goto release;
        }

        if (m->m_pkthdr.len == 0)
                goto release;

        if (m->m_pkthdr.len > pcb->lc_omtu) {
                error = EMSGSIZE;
                goto release;
        }

        m0 = m_copypacket(m, M_DONTWAIT);
        if (m0 == NULL) {
                error = ENOMEM;
                goto release;
        }

        sbappendrecord(&so->so_snd, m);
        return l2cap_send_pcb(pcb, m0);

release:
        m_freem(m);

        return error;
}

static int
l2cap_sendoob(struct socket *so, struct mbuf *m, struct mbuf *control)
{
        KASSERT(solocked(so));

        m_freem(m);
        m_freem(control);

        return EOPNOTSUPP;
}

static int
l2cap_purgeif(struct socket *so, struct ifnet *ifp)
{

        return EOPNOTSUPP;
}

/*
 * l2cap_ctloutput(req, socket, sockopt)
 *
 *      Apply configuration commands to channel. This corresponds to
 *      "Reconfigure Channel Request" in the L2CAP specification.
 */
int
l2cap_ctloutput(int req, struct socket *so, struct sockopt *sopt)
{
        struct l2cap_channel *pcb = so->so_pcb;
        int err = 0;

        DPRINTFN(2, "%s\n", prcorequests[req]);

        if (pcb == NULL)
                return EINVAL;

        if (sopt->sopt_level != BTPROTO_L2CAP)
                return ENOPROTOOPT;

        switch(req) {
        case PRCO_GETOPT:
                err = l2cap_getopt(pcb, sopt);
                break;

        case PRCO_SETOPT:
                err = l2cap_setopt(pcb, sopt);
                break;

        default:
                err = ENOPROTOOPT;
                break;
        }

        return err;
}

/**********************************************************************
 *
 *      L2CAP Protocol socket callbacks
 *
 */

static void
l2cap_connecting(void *arg)
{
        struct socket *so = arg;

        DPRINTF("Connecting\n");
        soisconnecting(so);
}

static void
l2cap_connected(void *arg)
{
        struct socket *so = arg;

        DPRINTF("Connected\n");
        soisconnected(so);
}

static void
l2cap_disconnected(void *arg, int err)
{
        struct socket *so = arg;

        DPRINTF("Disconnected (%d)\n", err);

        so->so_error = err;
        soisdisconnected(so);
}

static void *
l2cap_newconn(void *arg, struct sockaddr_bt *laddr,
    struct sockaddr_bt *raddr)
{
        struct socket *so = arg;

        DPRINTF("New Connection\n");
        so = sonewconn(so, false);
        if (so == NULL)
                return NULL;

        soisconnecting(so);

        return so->so_pcb;
}

static void
l2cap_complete(void *arg, int count)
{
        struct socket *so = arg;

        while (count-- > 0)
                sbdroprecord(&so->so_snd);

        sowwakeup(so);
}

static void
l2cap_linkmode(void *arg, int new)
{
        struct socket *so = arg;
        struct sockopt sopt;
        int mode;

        DPRINTF("auth %s, encrypt %s, secure %s\n",
                (new & L2CAP_LM_AUTH ? "on" : "off"),
                (new & L2CAP_LM_ENCRYPT ? "on" : "off"),
                (new & L2CAP_LM_SECURE ? "on" : "off"));

        sockopt_init(&sopt, BTPROTO_L2CAP, SO_L2CAP_LM, 0);
        (void)l2cap_getopt(so->so_pcb, &sopt);
        (void)sockopt_getint(&sopt, &mode);
        sockopt_destroy(&sopt);

        if (((mode & L2CAP_LM_AUTH) && !(new & L2CAP_LM_AUTH))
            || ((mode & L2CAP_LM_ENCRYPT) && !(new & L2CAP_LM_ENCRYPT))
            || ((mode & L2CAP_LM_SECURE) && !(new & L2CAP_LM_SECURE)))
                l2cap_disconnect_pcb(so->so_pcb, 0);
}

static void
l2cap_input(void *arg, struct mbuf *m)
{
        struct socket *so = arg;

        if (m->m_pkthdr.len > sbspace(&so->so_rcv)) {
                printf("%s: packet (%d bytes) dropped (socket buffer full)\n",
                        __func__, m->m_pkthdr.len);
                m_freem(m);
                return;
        }

        DPRINTFN(10, "received %d bytes\n", m->m_pkthdr.len);

        sbappendrecord(&so->so_rcv, m);
        sorwakeup(so);
}

PR_WRAP_USRREQS(l2cap)

#define l2cap_attach            l2cap_attach_wrapper
#define l2cap_detach            l2cap_detach_wrapper
#define l2cap_accept            l2cap_accept_wrapper
#define l2cap_bind              l2cap_bind_wrapper
#define l2cap_listen            l2cap_listen_wrapper
#define l2cap_connect           l2cap_connect_wrapper
#define l2cap_connect2          l2cap_connect2_wrapper
#define l2cap_disconnect        l2cap_disconnect_wrapper
#define l2cap_shutdown          l2cap_shutdown_wrapper
#define l2cap_abort             l2cap_abort_wrapper
#define l2cap_ioctl             l2cap_ioctl_wrapper
#define l2cap_stat              l2cap_stat_wrapper
#define l2cap_peeraddr          l2cap_peeraddr_wrapper
#define l2cap_sockaddr          l2cap_sockaddr_wrapper
#define l2cap_rcvd              l2cap_rcvd_wrapper
#define l2cap_recvoob           l2cap_recvoob_wrapper
#define l2cap_send              l2cap_send_wrapper
#define l2cap_sendoob           l2cap_sendoob_wrapper
#define l2cap_purgeif           l2cap_purgeif_wrapper

const struct pr_usrreqs l2cap_usrreqs = {
        .pr_attach      = l2cap_attach,
        .pr_detach      = l2cap_detach,
        .pr_accept      = l2cap_accept,
        .pr_bind        = l2cap_bind,
        .pr_listen      = l2cap_listen,
        .pr_connect     = l2cap_connect,
        .pr_connect2    = l2cap_connect2,
        .pr_disconnect  = l2cap_disconnect,
        .pr_shutdown    = l2cap_shutdown,
        .pr_abort       = l2cap_abort,
        .pr_ioctl       = l2cap_ioctl,
        .pr_stat        = l2cap_stat,
        .pr_peeraddr    = l2cap_peeraddr,
        .pr_sockaddr    = l2cap_sockaddr,
        .pr_rcvd        = l2cap_rcvd,
        .pr_recvoob     = l2cap_recvoob,
        .pr_send        = l2cap_send,
        .pr_sendoob     = l2cap_sendoob,
        .pr_purgeif     = l2cap_purgeif,
};