/*      $NetBSD: evt.c,v 1.12 2025/03/07 15:55:29 christos Exp $        */

/* Id: evt.c,v 1.5 2006/06/22 20:11:35 manubsd Exp */

/*
 * Copyright (C) 2004 Emmanuel Dreyfus
 * Copyright (C) 2008 Timo Teras
 * 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.
 */

#include "config.h"

#include <errno.h>
#include <string.h>
#include <stdio.h>
#include <time.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/queue.h>
#include <sys/socket.h>

#include "vmbuf.h"
#include "plog.h"
#include "misc.h"
#include "admin.h"
#include "handler.h"
#include "session.h"
#include "gcmalloc.h"
#include "evt.h"
#include "var.h"

#ifdef ENABLE_ADMINPORT

static EVT_LISTENER_LIST(evt_listeners);

struct evt_message {
        struct admin_com adm;
        struct evt_async evt;
};

struct evt {
        struct evtdump *dump;
        TAILQ_ENTRY(evt) next;
};

TAILQ_HEAD(evtlist, evt);

#define EVTLIST_MAX     32

static struct evtlist evtlist = TAILQ_HEAD_INITIALIZER(evtlist);
static int evtlist_len = 0;
static int evtlist_inuse = 0;

static struct {
        int newtype, oldtype;
} evttype_map[] = {
        { EVT_RACOON_QUIT,              EVTT_RACOON_QUIT },
        { EVT_PHASE1_UP,                EVTT_PHASE1_UP },
        { EVT_PHASE1_DOWN,              EVTT_PHASE1_DOWN },
        { EVT_PHASE1_NO_RESPONSE,       EVTT_PEER_NO_RESPONSE },
        { EVT_PHASE1_NO_PROPOSAL,       EVTT_PEERPH1_NOPROP },
        { EVT_PHASE1_AUTH_FAILED,       EVTT_PEERPH1AUTH_FAILED },
        { EVT_PHASE1_DPD_TIMEOUT,       EVTT_DPD_TIMEOUT },
        { EVT_PHASE1_PEER_DELETED,      EVTT_PEER_DELETE },
        { EVT_PHASE1_MODE_CFG,          EVTT_ISAKMP_CFG_DONE },
        { EVT_PHASE1_XAUTH_SUCCESS,     EVTT_XAUTH_SUCCESS },
        { EVT_PHASE1_XAUTH_FAILED,      EVTT_XAUTH_FAILED },
        { EVT_PHASE2_NO_PHASE1,         -1 },
        { EVT_PHASE2_UP,                EVTT_PHASE2_UP },
        { EVT_PHASE2_DOWN,              EVTT_PHASE2_DOWN },
        { EVT_PHASE2_NO_RESPONSE,       EVTT_PEER_NO_RESPONSE },
};

static void
evt_push(struct sockaddr_storage *src, struct sockaddr_storage *dst, int type, vchar_t *optdata)
{
        struct evtdump *evtdump;
        struct evt *evt;
        size_t len;
        int i;

        /* If admin socket is disabled, silently discard anything */
        if (adminsock_path == NULL || !evtlist_inuse)
                return;

        /* Map the event type to old */
        for (i = 0; i < sizeof(evttype_map) / sizeof(evttype_map[0]); i++)
                if (evttype_map[i].newtype == type)
                        break;
        if (i >= sizeof(evttype_map) / sizeof(evttype_map[0]))
                return;

        type = evttype_map[i].oldtype;
        if (type < 0)
                return;

        /* If we are above the limit, don't record anything */
        if (evtlist_len > EVTLIST_MAX) {
                plog(LLV_DEBUG, LOCATION, NULL, 
                    "Cannot record event: event queue overflowed\n");
                return;
        }

        /* If we hit the limit, record an overflow event instead */
        if (evtlist_len == EVTLIST_MAX) {
                plog(LLV_ERROR, LOCATION, NULL, 
                    "Cannot record event: event queue overflow\n");
                src = NULL;
                dst = NULL;
                type = EVTT_OVERFLOW;
                optdata = NULL;
        }

        len = sizeof(*evtdump);
        if (optdata)
                len += optdata->l;

        if ((evtdump = racoon_malloc(len)) == NULL) {
                plog(LLV_ERROR, LOCATION, NULL, "Cannot record event: %s\n",
                    strerror(errno));
                return;
        }

        if ((evt = racoon_malloc(sizeof(*evt))) == NULL) {
                plog(LLV_ERROR, LOCATION, NULL, "Cannot record event: %s\n",
                    strerror(errno));
                racoon_free(evtdump);
                return;
        }

        if (src)
                memcpy(&evtdump->src, src, sysdep_sa_len((struct sockaddr *)src));
        if (dst)
                memcpy(&evtdump->dst, dst, sysdep_sa_len((struct sockaddr *)dst));
        evtdump->len = len;
        evtdump->type = type;
        time(&evtdump->timestamp);

        if (optdata)
                memcpy(evtdump + 1, optdata->v, optdata->l);

        evt->dump = evtdump;
        TAILQ_INSERT_TAIL(&evtlist, evt, next);

        evtlist_len++;

        return;
}

static struct evtdump *
evt_pop(void) {
        struct evtdump *evtdump;
        struct evt *evt;

        if ((evt = TAILQ_FIRST(&evtlist)) == NULL)
                return NULL;

        evtdump = evt->dump;
        TAILQ_REMOVE(&evtlist, evt, next);
        racoon_free(evt);
        evtlist_len--;

        return evtdump;
}

vchar_t *
evt_dump(void) {
        struct evtdump *evtdump;
        vchar_t *buf = NULL;

        if (!evtlist_inuse) {
                evtlist_inuse = 1;
                plog(LLV_ERROR, LOCATION, NULL,
                     "evt_dump: deprecated event polling used\n");
        }

        if ((evtdump = evt_pop()) != NULL) {
                if ((buf = vmalloc(evtdump->len)) == NULL) {
                        plog(LLV_ERROR, LOCATION, NULL, 
                            "evt_dump failed: %s\n", strerror(errno));
                        return NULL;
                }
                memcpy(buf->v, evtdump, evtdump->len);  
                racoon_free(evtdump);
        }

        return buf;
}

static struct evt_message *
evtmsg_create(int type, vchar_t *optdata)
{
        struct evt_message *e;
        size_t len;

        len = sizeof(struct evt_message);
        if (optdata != NULL)
                len += optdata->l;

        if ((e = racoon_malloc(len)) == NULL) {
                plog(LLV_ERROR, LOCATION, NULL, "Cannot allocate event: %s\n",
                     strerror(errno));
                return NULL;
        }

        memset(e, 0, sizeof(struct evt_message));
        e->adm.ac_len = len;
        e->adm.ac_cmd = ADMIN_SHOW_EVT;
        e->adm.ac_errno = 0;
        e->adm.ac_proto = 0;
        e->evt.ec_type = type;
        time(&e->evt.ec_timestamp);
        if (optdata != NULL)
                memcpy(e + 1, optdata->v, optdata->l);

        return e;
}

static void
evt_unsubscribe(struct evt_listener *l)
{
        plog(LLV_DEBUG, LOCATION, NULL,
             "[%d] admin connection released\n", l->fd);

        LIST_REMOVE(l, ll_chain);
        unmonitor_fd(l->fd);
        close(l->fd);
        racoon_free(l);
}

/*ARGSUSED*/
static int
evt_unsubscribe_cb(void *ctx, int fd __unused)
{
        evt_unsubscribe((struct evt_listener *) ctx);
        return 0;
}

static void
evtmsg_broadcast(const struct evt_listener_list *ll, struct evt_message *e)
{
        struct evt_listener *l, *nl;

        for (l = LIST_FIRST(ll); l != NULL; l = nl) {
                nl = LIST_NEXT(l, ll_chain);

                if (send(l->fd, e, e->adm.ac_len, MSG_DONTWAIT) < 0) {
                        plog(LLV_DEBUG, LOCATION, NULL, "Cannot send event to fd: %s\n",
                                strerror(errno));
                        evt_unsubscribe(l);
                }
        }
}

void
evt_generic(int type, vchar_t *optdata)
{
        struct evt_message *e;

        if ((e = evtmsg_create(type, optdata)) == NULL)
                return;

        evtmsg_broadcast(&evt_listeners, e);
        evt_push(&e->evt.ec_ph1src, &e->evt.ec_ph1dst, type, optdata);

        racoon_free(e);
}

void
evt_phase1(const struct ph1handle *ph1, int type, vchar_t *optdata)
{
        struct evt_message *e;

        if ((e = evtmsg_create(type, optdata)) == NULL)
                return;

        if (ph1->local)
                memcpy(&e->evt.ec_ph1src, ph1->local, sysdep_sa_len(ph1->local));
        if (ph1->remote)
                memcpy(&e->evt.ec_ph1dst, ph1->remote, sysdep_sa_len(ph1->remote));

        evtmsg_broadcast(&ph1->evt_listeners, e);
        evtmsg_broadcast(&evt_listeners, e);
        evt_push(&e->evt.ec_ph1src, &e->evt.ec_ph1dst, type, optdata);

        racoon_free(e);
}

void
evt_phase2(const struct ph2handle *ph2, int type, vchar_t *optdata)
{
        struct evt_message *e;
        struct ph1handle *ph1 = ph2->ph1;

        if ((e = evtmsg_create(type, optdata)) == NULL)
                return;

        if (ph1) {
                if (ph1->local)
                        memcpy(&e->evt.ec_ph1src, ph1->local, sysdep_sa_len(ph1->local));
                if (ph1->remote)
                        memcpy(&e->evt.ec_ph1dst, ph1->remote, sysdep_sa_len(ph1->remote));
        }
        e->evt.ec_ph2msgid = ph2->msgid;

        evtmsg_broadcast(&ph2->evt_listeners, e);
        if (ph1)
                evtmsg_broadcast(&ph1->evt_listeners, e);
        evtmsg_broadcast(&evt_listeners, e);
        evt_push(&e->evt.ec_ph1src, &e->evt.ec_ph1dst, type, optdata);

        racoon_free(e);
}

int
evt_subscribe(struct evt_listener_list *list, int fd)
{
        struct evt_listener *l;

        if ((l = racoon_malloc(sizeof(*l))) == NULL) {
                plog(LLV_ERROR, LOCATION, NULL,
                     "Cannot allocate event listener: %s\n",
                     strerror(errno));
                return errno;
        }

        if (list == NULL)
                list = &evt_listeners;

        LIST_INSERT_HEAD(list, l, ll_chain);
        l->fd = fd;
        monitor_fd(l->fd, evt_unsubscribe_cb, l, 0);

        plog(LLV_DEBUG, LOCATION, NULL,
             "[%d] admin connection is polling events\n", fd);

        return -2;
}

void
evt_list_init(struct evt_listener_list *list)
{
        LIST_INIT(list);
}

void
evt_list_cleanup(struct evt_listener_list *list)
{
        while (!LIST_EMPTY(list))
                evt_unsubscribe(LIST_FIRST(list));
}

#endif /* ENABLE_ADMINPORT */