/*-
 * Copyright (c) 2012 The FreeBSD Foundation
 *
 * This software was developed by Edward Tomasz Napierala under sponsorship
 * from the FreeBSD Foundation.
 *
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
 *
 */
/*-
 * Copyright (c) 1982, 1986, 1989, 1990, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * sendfile(2) and related extensions:
 * Copyright (c) 1998, David Greenman. 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 University 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 REGENTS 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 REGENTS 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.
 */

/*
 * iSCSI Common Layer, kernel proxy part.
 */

#ifdef ICL_KERNEL_PROXY

#include <sys/param.h>
#include <sys/capsicum.h>
#include <sys/condvar.h>
#include <sys/conf.h>
#include <sys/lock.h>
#include <sys/kernel.h>
#include <sys/kthread.h>
#include <sys/malloc.h>
#include <sys/mutex.h>
#include <sys/proc.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sx.h>
#include <sys/systm.h>
#include <netinet/in.h>
#include <netinet/tcp.h>

#include <dev/iscsi/icl.h>

struct icl_listen_sock {
        TAILQ_ENTRY(icl_listen_sock)    ils_next;
        struct icl_listen               *ils_listen;
        struct socket                   *ils_socket;
        bool                            ils_running;
        int                             ils_id;
};

struct icl_listen       {
        TAILQ_HEAD(, icl_listen_sock)   il_sockets;
        struct sx                       il_lock;
        void                            (*il_accept)(struct socket *,
                                            struct sockaddr *, int);
};

static MALLOC_DEFINE(M_ICL_PROXY, "ICL_PROXY", "iSCSI common layer proxy");

int
icl_soft_proxy_connect(struct icl_conn *ic, int domain, int socktype,
    int protocol, struct sockaddr *from_sa, struct sockaddr *to_sa)
{
        struct socket *so;
        int error;

        error = socreate(domain, &so, socktype, protocol,
            curthread->td_ucred, curthread);
        if (error != 0)
                return (error);

        if (from_sa != NULL) {
                error = sobind(so, from_sa, curthread);
                if (error != 0) {
                        soclose(so);
                        return (error);
                }
        }

        error = soconnect(so, to_sa, curthread);
        if (error != 0) {
                soclose(so);
                return (error);
        }

        SOCK_LOCK(so);
        while ((so->so_state & SS_ISCONNECTING) && so->so_error == 0) {
                error = msleep(&so->so_timeo, SOCK_MTX(so), PSOCK | PCATCH,
                    "icl_connect", 0);
                if (error)
                        break;
        }
        if (error == 0) {
                error = so->so_error;
                so->so_error = 0;
        }
        SOCK_UNLOCK(so);

        if (error != 0) {
                soclose(so);
                return (error);
        }

        error = icl_soft_handoff_sock(ic, so);
        if (error != 0)
                soclose(so);

        return (error);
}

struct icl_listen *
icl_listen_new(void (*accept_cb)(struct socket *, struct sockaddr *, int))
{
        struct icl_listen *il;

        il = malloc(sizeof(*il), M_ICL_PROXY, M_ZERO | M_WAITOK);
        TAILQ_INIT(&il->il_sockets);
        sx_init(&il->il_lock, "icl_listen");
        il->il_accept = accept_cb;

        return (il);
}

void
icl_listen_free(struct icl_listen *il)
{
        struct icl_listen_sock *ils;
        sbintime_t sbt, pr;

        sx_xlock(&il->il_lock);
        while (!TAILQ_EMPTY(&il->il_sockets)) {
                ils = TAILQ_FIRST(&il->il_sockets);
                while (ils->ils_running) {
                        ICL_DEBUG("waiting for accept thread to terminate");
                        sx_xunlock(&il->il_lock);
                        SOLISTEN_LOCK(ils->ils_socket);
                        ils->ils_socket->so_error = ENOTCONN;
                        SOLISTEN_UNLOCK(ils->ils_socket);
                        wakeup(&ils->ils_socket->so_timeo);
                        sbt = mstosbt(995);
                        pr = mstosbt(10);
                        pause_sbt("icl_unlisten", sbt, pr, 0);
                        sx_xlock(&il->il_lock);
                }

                TAILQ_REMOVE(&il->il_sockets, ils, ils_next);
                soclose(ils->ils_socket);
                free(ils, M_ICL_PROXY);
        }
        sx_xunlock(&il->il_lock);

        free(il, M_ICL_PROXY);
}

/*
 * XXX: Doing accept in a separate thread in each socket might not be the
 * best way to do stuff, but it's pretty clean and debuggable - and you
 * probably won't have hundreds of listening sockets anyway.
 */
static void
icl_accept_thread(void *arg)
{
        struct icl_listen_sock *ils;
        struct socket *head, *so;
        struct sockaddr_storage ss = { .ss_len = sizeof(ss) };
        int error;

        ils = arg;
        head = ils->ils_socket;

        ils->ils_running = true;

        for (;;) {
                SOLISTEN_LOCK(head);
                error = solisten_dequeue(head, &so, 0);
                if (error == ENOTCONN) {
                        /*
                         * XXXGL: ENOTCONN is our mark from icl_listen_free().
                         * Neither socket code, nor msleep(9) may return it.
                         */
                        ICL_DEBUG("terminating");
                        ils->ils_running = false;
                        kthread_exit();
                        return;
                }
                if (error) {
                        ICL_WARN("solisten_dequeue error %d", error);
                        continue;
                }

                error = soaccept(so, (struct sockaddr *)&ss);
                if (error != 0) {
                        ICL_WARN("soaccept error %d", error);
                        soclose(so);
                        continue;
                }

                (ils->ils_listen->il_accept)(so, (struct sockaddr *)&ss,
                    ils->ils_id);
        }
}

static int
icl_listen_add_tcp(struct icl_listen *il, int domain, int socktype,
    int protocol, struct sockaddr *sa, int portal_id)
{
        struct icl_listen_sock *ils;
        struct socket *so;
        struct sockopt sopt;
        int error, one = 1;

        error = socreate(domain, &so, socktype, protocol,
            curthread->td_ucred, curthread);
        if (error != 0) {
                ICL_WARN("socreate failed with error %d", error);
                return (error);
        }

        sopt.sopt_dir = SOPT_SET;
        sopt.sopt_level = SOL_SOCKET;
        sopt.sopt_name = SO_REUSEADDR;
        sopt.sopt_val = &one;
        sopt.sopt_valsize = sizeof(one);
        sopt.sopt_td = NULL;
        error = sosetopt(so, &sopt);
        if (error != 0) {
                ICL_WARN("failed to set SO_REUSEADDR with error %d", error);
                soclose(so);
                return (error);
        }

        error = sobind(so, sa, curthread);
        if (error != 0) {
                ICL_WARN("sobind failed with error %d", error);
                soclose(so);
                return (error);
        }

        error = solisten(so, -1, curthread);
        if (error != 0) {
                ICL_WARN("solisten failed with error %d", error);
                soclose(so);
                return (error);
        }

        ils = malloc(sizeof(*ils), M_ICL_PROXY, M_ZERO | M_WAITOK);
        ils->ils_listen = il;
        ils->ils_socket = so;
        ils->ils_id = portal_id;

        error = kthread_add(icl_accept_thread, ils, NULL, NULL, 0, 0, "iclacc");
        if (error != 0) {
                ICL_WARN("kthread_add failed with error %d", error);
                soclose(so);
                free(ils, M_ICL_PROXY);

                return (error);
        }

        sx_xlock(&il->il_lock);
        TAILQ_INSERT_TAIL(&il->il_sockets, ils, ils_next);
        sx_xunlock(&il->il_lock);

        return (0);
}

int
icl_listen_add(struct icl_listen *il, bool rdma, int domain, int socktype,
    int protocol, struct sockaddr *sa, int portal_id)
{

        if (rdma) {
                ICL_DEBUG("RDMA not supported");
                return (EOPNOTSUPP);
        }

        return (icl_listen_add_tcp(il, domain, socktype, protocol, sa,
            portal_id));
}

int
icl_listen_remove(struct icl_listen *il, struct sockaddr *sa)
{

        /*
         * XXX
         */

        return (EOPNOTSUPP);
}

#endif /* ICL_KERNEL_PROXY */