/*      $OpenBSD: queue.c,v 1.196 2024/01/20 09:01:03 claudio Exp $     */

/*
 * Copyright (c) 2008 Gilles Chehade <gilles@poolp.org>
 * Copyright (c) 2008 Pierre-Yves Ritschard <pyr@openbsd.org>
 * Copyright (c) 2012 Eric Faurot <eric@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <inttypes.h>
#include <pwd.h>
#include <signal.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>

#include "smtpd.h"
#include "log.h"

static void queue_imsg(struct mproc *, struct imsg *);
static void queue_timeout(int, short, void *);
static void queue_bounce(struct envelope *, struct delivery_bounce *);
static void queue_shutdown(void);
static void queue_log(const struct envelope *, const char *, const char *);
static void queue_msgid_walk(int, short, void *);


static void
queue_imsg(struct mproc *p, struct imsg *imsg)
{
        struct delivery_bounce   bounce;
        struct msg_walkinfo     *wi;
        struct timeval           tv;
        struct bounce_req_msg   *req_bounce;
        struct envelope          evp;
        struct msg               m;
        const char              *reason;
        uint64_t                 reqid, evpid, holdq;
        uint32_t                 msgid;
        time_t                   nexttry;
        size_t                   n_evp;
        int                      fd, mta_ext, ret, v, flags, code;

        if (imsg == NULL)
                queue_shutdown();

        memset(&bounce, 0, sizeof(struct delivery_bounce));

        switch (imsg->hdr.type) {
        case IMSG_SMTP_MESSAGE_CREATE:
                m_msg(&m, imsg);
                m_get_id(&m, &reqid);
                m_end(&m);

                ret = queue_message_create(&msgid);

                m_create(p, IMSG_SMTP_MESSAGE_CREATE, 0, 0, -1);
                m_add_id(p, reqid);
                if (ret == 0)
                        m_add_int(p, 0);
                else {
                        m_add_int(p, 1);
                        m_add_msgid(p, msgid);
                }
                m_close(p);
                return;

        case IMSG_SMTP_MESSAGE_ROLLBACK:
                m_msg(&m, imsg);
                m_get_msgid(&m, &msgid);
                m_end(&m);

                queue_message_delete(msgid);

                m_create(p_scheduler, IMSG_QUEUE_MESSAGE_ROLLBACK,
                    0, 0, -1);
                m_add_msgid(p_scheduler, msgid);
                m_close(p_scheduler);
                return;

        case IMSG_SMTP_MESSAGE_COMMIT:
                m_msg(&m, imsg);
                m_get_id(&m, &reqid);
                m_get_msgid(&m, &msgid);
                m_end(&m);

                ret = queue_message_commit(msgid);

                m_create(p, IMSG_SMTP_MESSAGE_COMMIT, 0, 0, -1);
                m_add_id(p, reqid);
                m_add_int(p, (ret == 0) ? 0 : 1);
                m_close(p);

                if (ret) {
                        m_create(p_scheduler, IMSG_QUEUE_MESSAGE_COMMIT,
                            0, 0, -1);
                        m_add_msgid(p_scheduler, msgid);
                        m_close(p_scheduler);
                }
                return;

        case IMSG_SMTP_MESSAGE_OPEN:
                m_msg(&m, imsg);
                m_get_id(&m, &reqid);
                m_get_msgid(&m, &msgid);
                m_end(&m);

                fd = queue_message_fd_rw(msgid);

                m_create(p, IMSG_SMTP_MESSAGE_OPEN, 0, 0, fd);
                m_add_id(p, reqid);
                m_add_int(p, (fd == -1) ? 0 : 1);
                m_close(p);
                return;

        case IMSG_QUEUE_SMTP_SESSION:
                bounce_fd(imsg_get_fd(imsg));
                return;

        case IMSG_LKA_ENVELOPE_SUBMIT:
                m_msg(&m, imsg);
                m_get_id(&m, &reqid);
                m_get_envelope(&m, &evp);
                m_end(&m);

                if (evp.id == 0)
                        log_warnx("warn: imsg_queue_submit_envelope: evpid=0");
                if (evpid_to_msgid(evp.id) == 0)
                        log_warnx("warn: imsg_queue_submit_envelope: msgid=0, "
                            "evpid=%016"PRIx64, evp.id);
                ret = queue_envelope_create(&evp);
                m_create(p_dispatcher, IMSG_QUEUE_ENVELOPE_SUBMIT, 0, 0, -1);
                m_add_id(p_dispatcher, reqid);
                if (ret == 0)
                        m_add_int(p_dispatcher, 0);
                else {
                        m_add_int(p_dispatcher, 1);
                        m_add_evpid(p_dispatcher, evp.id);
                }
                m_close(p_dispatcher);
                if (ret) {
                        m_create(p_scheduler,
                            IMSG_QUEUE_ENVELOPE_SUBMIT, 0, 0, -1);
                        m_add_envelope(p_scheduler, &evp);
                        m_close(p_scheduler);
                }
                return;

        case IMSG_LKA_ENVELOPE_COMMIT:
                m_msg(&m, imsg);
                m_get_id(&m, &reqid);
                m_end(&m);
                m_create(p_dispatcher, IMSG_QUEUE_ENVELOPE_COMMIT, 0, 0, -1);
                m_add_id(p_dispatcher, reqid);
                m_add_int(p_dispatcher, 1);
                m_close(p_dispatcher);
                return;

        case IMSG_SCHED_ENVELOPE_REMOVE:
                m_msg(&m, imsg);
                m_get_evpid(&m, &evpid);
                m_end(&m);

                m_create(p_scheduler, IMSG_QUEUE_ENVELOPE_ACK, 0, 0, -1);
                m_add_evpid(p_scheduler, evpid);
                m_close(p_scheduler);

                /* already removed by scheduler */
                if (queue_envelope_load(evpid, &evp) == 0)
                        return;

                queue_log(&evp, "Remove", "Removed by administrator");
                queue_envelope_delete(evpid);
                return;

        case IMSG_SCHED_ENVELOPE_EXPIRE:
                m_msg(&m, imsg);
                m_get_evpid(&m, &evpid);
                m_end(&m);

                m_create(p_scheduler, IMSG_QUEUE_ENVELOPE_ACK, 0, 0, -1);
                m_add_evpid(p_scheduler, evpid);
                m_close(p_scheduler);

                /* already removed by scheduler*/
                if (queue_envelope_load(evpid, &evp) == 0)
                        return;

                bounce.type = B_FAILED;
                envelope_set_errormsg(&evp, "Envelope expired");
                envelope_set_esc_class(&evp, ESC_STATUS_PERMFAIL);
                envelope_set_esc_code(&evp, ESC_DELIVERY_TIME_EXPIRED);
                queue_bounce(&evp, &bounce);
                queue_log(&evp, "Expire", "Envelope expired");
                queue_envelope_delete(evpid);
                return;

        case IMSG_SCHED_ENVELOPE_BOUNCE:
                CHECK_IMSG_DATA_SIZE(imsg, sizeof *req_bounce);
                req_bounce = imsg->data;
                evpid = req_bounce->evpid;

                if (queue_envelope_load(evpid, &evp) == 0) {
                        log_warnx("queue: bounce: failed to load envelope");
                        m_create(p_scheduler, IMSG_QUEUE_ENVELOPE_REMOVE, 0, 0, -1);
                        m_add_evpid(p_scheduler, evpid);
                        m_add_u32(p_scheduler, 0); /* not in-flight */
                        m_close(p_scheduler);
                        return;
                }
                queue_bounce(&evp, &req_bounce->bounce);
                evp.lastbounce = req_bounce->timestamp;
                if (!queue_envelope_update(&evp))
                        log_warnx("warn: could not update envelope %016"PRIx64, evpid);
                return;

        case IMSG_SCHED_ENVELOPE_DELIVER:
                m_msg(&m, imsg);
                m_get_evpid(&m, &evpid);
                m_end(&m);
                if (queue_envelope_load(evpid, &evp) == 0) {
                        log_warnx("queue: deliver: failed to load envelope");
                        m_create(p_scheduler, IMSG_QUEUE_ENVELOPE_REMOVE, 0, 0, -1);
                        m_add_evpid(p_scheduler, evpid);
                        m_add_u32(p_scheduler, 1); /* in-flight */
                        m_close(p_scheduler);
                        return;
                }
                evp.lasttry = time(NULL);
                m_create(p_dispatcher, IMSG_QUEUE_DELIVER, 0, 0, -1);
                m_add_envelope(p_dispatcher, &evp);
                m_close(p_dispatcher);
                return;

        case IMSG_SCHED_ENVELOPE_INJECT:
                m_msg(&m, imsg);
                m_get_evpid(&m, &evpid);
                m_end(&m);
                bounce_add(evpid);
                return;

        case IMSG_SCHED_ENVELOPE_TRANSFER:
                m_msg(&m, imsg);
                m_get_evpid(&m, &evpid);
                m_end(&m);
                if (queue_envelope_load(evpid, &evp) == 0) {
                        log_warnx("queue: failed to load envelope");
                        m_create(p_scheduler, IMSG_QUEUE_ENVELOPE_REMOVE, 0, 0, -1);
                        m_add_evpid(p_scheduler, evpid);
                        m_add_u32(p_scheduler, 1); /* in-flight */
                        m_close(p_scheduler);
                        return;
                }
                evp.lasttry = time(NULL);
                m_create(p_dispatcher, IMSG_QUEUE_TRANSFER, 0, 0, -1);
                m_add_envelope(p_dispatcher, &evp);
                m_close(p_dispatcher);
                return;

        case IMSG_CTL_LIST_ENVELOPES:
                if (imsg->hdr.len == sizeof imsg->hdr) {
                        m_forward(p_control, imsg);
                        return;
                }

                m_msg(&m, imsg);
                m_get_evpid(&m, &evpid);
                m_get_int(&m, &flags);
                m_get_time(&m, &nexttry);
                m_end(&m);

                if (queue_envelope_load(evpid, &evp) == 0)
                        return; /* Envelope is gone, drop it */

                /*
                 * XXX consistency: The envelope might already be on
                 * its way back to the scheduler.  We need to detect
                 * this properly and report that state.
                 */
                if (flags & EF_INFLIGHT) {
                        /*
                         * Not exactly correct but pretty close: The
                         * value is not recorded on the envelope unless
                         * a tempfail occurs.
                         */
                        evp.lasttry = nexttry;
                }

                m_create(p_control, IMSG_CTL_LIST_ENVELOPES,
                    imsg->hdr.peerid, 0, -1);
                m_add_int(p_control, flags);
                m_add_time(p_control, nexttry);
                m_add_envelope(p_control, &evp);
                m_close(p_control);
                return;

        case IMSG_MDA_OPEN_MESSAGE:
        case IMSG_MTA_OPEN_MESSAGE:
                m_msg(&m, imsg);
                m_get_id(&m, &reqid);
                m_get_msgid(&m, &msgid);
                m_end(&m);
                fd = queue_message_fd_r(msgid);
                m_create(p, imsg->hdr.type, 0, 0, fd);
                m_add_id(p, reqid);
                m_close(p);
                return;

        case IMSG_MDA_DELIVERY_OK:
        case IMSG_MTA_DELIVERY_OK:
                m_msg(&m, imsg);
                m_get_evpid(&m, &evpid);
                if (imsg->hdr.type == IMSG_MTA_DELIVERY_OK)
                        m_get_int(&m, &mta_ext);
                m_end(&m);
                if (queue_envelope_load(evpid, &evp) == 0) {
                        log_warn("queue: dsn: failed to load envelope");
                        return;
                }
                if (evp.dsn_notify & DSN_SUCCESS) {
                        bounce.type = B_DELIVERED;
                        bounce.dsn_ret = evp.dsn_ret;
                        envelope_set_esc_class(&evp, ESC_STATUS_OK);
                        if (imsg->hdr.type == IMSG_MDA_DELIVERY_OK)
                                queue_bounce(&evp, &bounce);
                        else if (imsg->hdr.type == IMSG_MTA_DELIVERY_OK &&
                            (mta_ext & MTA_EXT_DSN) == 0) {
                                bounce.mta_without_dsn = 1;
                                queue_bounce(&evp, &bounce);
                        }
                }
                queue_envelope_delete(evpid);
                m_create(p_scheduler, IMSG_QUEUE_DELIVERY_OK, 0, 0, -1);
                m_add_evpid(p_scheduler, evpid);
                m_close(p_scheduler);
                return;

        case IMSG_MDA_DELIVERY_TEMPFAIL:
        case IMSG_MTA_DELIVERY_TEMPFAIL:
                m_msg(&m, imsg);
                m_get_evpid(&m, &evpid);
                m_get_string(&m, &reason);
                m_get_int(&m, &code);
                m_end(&m);
                if (queue_envelope_load(evpid, &evp) == 0) {
                        log_warnx("queue: tempfail: failed to load envelope");
                        m_create(p_scheduler, IMSG_QUEUE_ENVELOPE_REMOVE, 0, 0, -1);
                        m_add_evpid(p_scheduler, evpid);
                        m_add_u32(p_scheduler, 1); /* in-flight */
                        m_close(p_scheduler);
                        return;
                }
                envelope_set_errormsg(&evp, "%s", reason);
                envelope_set_esc_class(&evp, ESC_STATUS_TEMPFAIL);
                envelope_set_esc_code(&evp, code);
                evp.retry++;
                if (!queue_envelope_update(&evp))
                        log_warnx("warn: could not update envelope %016"PRIx64, evpid);
                m_create(p_scheduler, IMSG_QUEUE_DELIVERY_TEMPFAIL, 0, 0, -1);
                m_add_envelope(p_scheduler, &evp);
                m_close(p_scheduler);
                return;

        case IMSG_MDA_DELIVERY_PERMFAIL:
        case IMSG_MTA_DELIVERY_PERMFAIL:
                m_msg(&m, imsg);
                m_get_evpid(&m, &evpid);
                m_get_string(&m, &reason);
                m_get_int(&m, &code);
                m_end(&m);
                if (queue_envelope_load(evpid, &evp) == 0) {
                        log_warnx("queue: permfail: failed to load envelope");
                        m_create(p_scheduler, IMSG_QUEUE_ENVELOPE_REMOVE, 0, 0, -1);
                        m_add_evpid(p_scheduler, evpid);
                        m_add_u32(p_scheduler, 1); /* in-flight */
                        m_close(p_scheduler);
                        return;
                }
                bounce.type = B_FAILED;
                envelope_set_errormsg(&evp, "%s", reason);
                envelope_set_esc_class(&evp, ESC_STATUS_PERMFAIL);
                envelope_set_esc_code(&evp, code);
                queue_bounce(&evp, &bounce);
                queue_envelope_delete(evpid);
                m_create(p_scheduler, IMSG_QUEUE_DELIVERY_PERMFAIL, 0, 0, -1);
                m_add_evpid(p_scheduler, evpid);
                m_close(p_scheduler);
                return;

        case IMSG_MDA_DELIVERY_LOOP:
        case IMSG_MTA_DELIVERY_LOOP:
                m_msg(&m, imsg);
                m_get_evpid(&m, &evpid);
                m_end(&m);
                if (queue_envelope_load(evpid, &evp) == 0) {
                        log_warnx("queue: loop: failed to load envelope");
                        m_create(p_scheduler, IMSG_QUEUE_ENVELOPE_REMOVE, 0, 0, -1);
                        m_add_evpid(p_scheduler, evpid);
                        m_add_u32(p_scheduler, 1); /* in-flight */
                        m_close(p_scheduler);
                        return;
                }
                envelope_set_errormsg(&evp, "%s", "Loop detected");
                envelope_set_esc_class(&evp, ESC_STATUS_TEMPFAIL);
                envelope_set_esc_code(&evp, ESC_ROUTING_LOOP_DETECTED);
                bounce.type = B_FAILED;
                queue_bounce(&evp, &bounce);
                queue_envelope_delete(evp.id);
                m_create(p_scheduler, IMSG_QUEUE_DELIVERY_LOOP, 0, 0, -1);
                m_add_evpid(p_scheduler, evp.id);
                m_close(p_scheduler);
                return;

        case IMSG_MTA_DELIVERY_HOLD:
        case IMSG_MDA_DELIVERY_HOLD:
                imsg->hdr.type = IMSG_QUEUE_HOLDQ_HOLD;
                m_forward(p_scheduler, imsg);
                return;

        case IMSG_MTA_SCHEDULE:
                imsg->hdr.type = IMSG_QUEUE_ENVELOPE_SCHEDULE;
                m_forward(p_scheduler, imsg);
                return;

        case IMSG_MTA_HOLDQ_RELEASE:
        case IMSG_MDA_HOLDQ_RELEASE:
                m_msg(&m, imsg);
                m_get_id(&m, &holdq);
                m_get_int(&m, &v);
                m_end(&m);
                m_create(p_scheduler, IMSG_QUEUE_HOLDQ_RELEASE, 0, 0, -1);
                if (imsg->hdr.type == IMSG_MTA_HOLDQ_RELEASE)
                        m_add_int(p_scheduler, D_MTA);
                else
                        m_add_int(p_scheduler, D_MDA);
                m_add_id(p_scheduler, holdq);
                m_add_int(p_scheduler, v);
                m_close(p_scheduler);
                return;

        case IMSG_CTL_PAUSE_MDA:
        case IMSG_CTL_PAUSE_MTA:
        case IMSG_CTL_RESUME_MDA:
        case IMSG_CTL_RESUME_MTA:
                m_forward(p_scheduler, imsg);
                return;

        case IMSG_CTL_VERBOSE:
                m_msg(&m, imsg);
                m_get_int(&m, &v);
                m_end(&m);
                log_trace_verbose(v);
                return;

        case IMSG_CTL_PROFILE:
                m_msg(&m, imsg);
                m_get_int(&m, &v);
                m_end(&m);
                profiling = v;
                return;

        case IMSG_CTL_DISCOVER_EVPID:
                m_msg(&m, imsg);
                m_get_evpid(&m, &evpid);
                m_end(&m);
                if (queue_envelope_load(evpid, &evp) == 0) {
                        log_warnx("queue: discover: failed to load "
                            "envelope %016" PRIx64, evpid);
                        n_evp = 0;
                        m_compose(p_control, imsg->hdr.type,
                            imsg->hdr.peerid, 0, -1,
                            &n_evp, sizeof n_evp);
                        return;
                }

                m_create(p_scheduler, IMSG_QUEUE_DISCOVER_EVPID,
                    0, 0, -1);
                m_add_envelope(p_scheduler, &evp);
                m_close(p_scheduler);

                m_create(p_scheduler, IMSG_QUEUE_DISCOVER_MSGID,
                    0, 0, -1);
                m_add_msgid(p_scheduler, evpid_to_msgid(evpid));
                m_close(p_scheduler);
                n_evp = 1;
                m_compose(p_control, imsg->hdr.type, imsg->hdr.peerid,
                    0, -1, &n_evp, sizeof n_evp);
                return;

        case IMSG_CTL_DISCOVER_MSGID:
                m_msg(&m, imsg);
                m_get_msgid(&m, &msgid);
                m_end(&m);
                /* handle concurrent walk requests */
                wi = xcalloc(1, sizeof *wi);
                wi->msgid = msgid;
                wi->peerid = imsg->hdr.peerid;
                evtimer_set(&wi->ev, queue_msgid_walk, wi);
                tv.tv_sec = 0;
                tv.tv_usec = 10;
                evtimer_add(&wi->ev, &tv);
                return;
        }

        fatalx("queue_imsg: unexpected %s imsg", imsg_to_str(imsg->hdr.type));
}

static void
queue_msgid_walk(int fd, short event, void *arg)
{
        struct envelope          evp;
        struct timeval           tv;
        struct msg_walkinfo     *wi = arg;
        int                      r;

        r = queue_message_walk(&evp, wi->msgid, &wi->done, &wi->data);
        if (r == -1) {
                if (wi->n_evp) {
                        m_create(p_scheduler, IMSG_QUEUE_DISCOVER_MSGID,
                            0, 0, -1);
                        m_add_msgid(p_scheduler, wi->msgid);
                        m_close(p_scheduler);
                }

                m_compose(p_control, IMSG_CTL_DISCOVER_MSGID, wi->peerid, 0, -1,
                    &wi->n_evp, sizeof wi->n_evp);
                evtimer_del(&wi->ev);
                free(wi);
                return;
        }

        if (r) {
                m_create(p_scheduler, IMSG_QUEUE_DISCOVER_EVPID, 0, 0, -1);
                m_add_envelope(p_scheduler, &evp);
                m_close(p_scheduler);
                wi->n_evp += 1;
        }

        tv.tv_sec = 0;
        tv.tv_usec = 10;
        evtimer_set(&wi->ev, queue_msgid_walk, wi);
        evtimer_add(&wi->ev, &tv);
}

static void
queue_bounce(struct envelope *e, struct delivery_bounce *d)
{
        struct envelope b;

        b = *e;
        b.type = D_BOUNCE;
        b.agent.bounce = *d;
        b.retry = 0;
        b.lasttry = 0;
        b.creation = time(NULL);
        b.ttl = 3600 * 24 * 7;

        if (e->dsn_notify & DSN_NEVER)
                return;

        if (b.id == 0)
                log_warnx("warn: queue_bounce: evpid=0");
        if (evpid_to_msgid(b.id) == 0)
                log_warnx("warn: queue_bounce: msgid=0, evpid=%016"PRIx64,
                        b.id);
        if (e->type == D_BOUNCE) {
                log_warnx("warn: queue: double bounce!");
        } else if (e->sender.user[0] == '\0') {
                log_warnx("warn: queue: no return path!");
        } else if (!queue_envelope_create(&b)) {
                log_warnx("warn: queue: cannot bounce!");
        } else {
                log_debug("debug: queue: bouncing evp:%016" PRIx64
                    " as evp:%016" PRIx64, e->id, b.id);

                m_create(p_scheduler, IMSG_QUEUE_ENVELOPE_SUBMIT, 0, 0, -1);
                m_add_envelope(p_scheduler, &b);
                m_close(p_scheduler);

                m_create(p_scheduler, IMSG_QUEUE_MESSAGE_COMMIT, 0, 0, -1);
                m_add_msgid(p_scheduler, evpid_to_msgid(b.id));
                m_close(p_scheduler);

                stat_increment("queue.bounce", 1);
        }
}

static void
queue_shutdown(void)
{
        log_debug("debug: queue agent exiting");
        queue_close();
        _exit(0);
}

int
queue(void)
{
        struct passwd   *pw;
        struct timeval   tv;
        struct event     ev_qload;

        purge_config(PURGE_EVERYTHING & ~PURGE_DISPATCHERS);

        if ((pw = getpwnam(SMTPD_QUEUE_USER)) == NULL)
                if ((pw = getpwnam(SMTPD_USER)) == NULL)
                        fatalx("unknown user " SMTPD_USER);

        env->sc_queue_flags |= QUEUE_EVPCACHE;
        env->sc_queue_evpcache_size = 1024;

        if (chroot(PATH_SPOOL) == -1)
                fatal("queue: chroot");
        if (chdir("/") == -1)
                fatal("queue: chdir(\"/\")");

        config_process(PROC_QUEUE);

        if (env->sc_queue_flags & QUEUE_COMPRESSION)
                log_info("queue: queue compression enabled");

        if (env->sc_queue_key) {
                if (!crypto_setup(env->sc_queue_key, strlen(env->sc_queue_key)))
                        fatalx("crypto_setup: invalid key for queue encryption");
                log_info("queue: queue encryption enabled");
        }

        if (setgroups(1, &pw->pw_gid) ||
            setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) ||
            setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid))
                fatal("queue: cannot drop privileges");

        imsg_callback = queue_imsg;
        event_init();

        signal(SIGINT, SIG_IGN);
        signal(SIGTERM, SIG_IGN);
        signal(SIGPIPE, SIG_IGN);
        signal(SIGHUP, SIG_IGN);

        config_peer(PROC_PARENT);
        config_peer(PROC_CONTROL);
        config_peer(PROC_LKA);
        config_peer(PROC_SCHEDULER);
        config_peer(PROC_DISPATCHER);

        /* setup queue loading task */
        evtimer_set(&ev_qload, queue_timeout, &ev_qload);
        tv.tv_sec = 0;
        tv.tv_usec = 10;
        evtimer_add(&ev_qload, &tv);

        if (pledge("stdio rpath wpath cpath flock recvfd sendfd", NULL) == -1)
                fatal("pledge");

        event_dispatch();
        fatalx("exited event loop");

        return (0);
}

static void
queue_timeout(int fd, short event, void *p)
{
        static uint32_t  msgid = 0;
        struct envelope  evp;
        struct event    *ev = p;
        struct timeval   tv;
        int              r;

        r = queue_envelope_walk(&evp);
        if (r == -1) {
                if (msgid) {
                        m_create(p_scheduler, IMSG_QUEUE_MESSAGE_COMMIT,
                            0, 0, -1);
                        m_add_msgid(p_scheduler, msgid);
                        m_close(p_scheduler);
                }
                log_debug("debug: queue: done loading queue into scheduler");
                return;
        }

        if (r) {
                if (msgid && evpid_to_msgid(evp.id) != msgid) {
                        m_create(p_scheduler, IMSG_QUEUE_MESSAGE_COMMIT,
                            0, 0, -1);
                        m_add_msgid(p_scheduler, msgid);
                        m_close(p_scheduler);
                }
                msgid = evpid_to_msgid(evp.id);
                m_create(p_scheduler, IMSG_QUEUE_ENVELOPE_SUBMIT, 0, 0, -1);
                m_add_envelope(p_scheduler, &evp);
                m_close(p_scheduler);
        }

        tv.tv_sec = 0;
        tv.tv_usec = 10;
        evtimer_add(ev, &tv);
}

static void
queue_log(const struct envelope *e, const char *prefix, const char *status)
{
        char rcpt[LINE_MAX];

        (void)strlcpy(rcpt, "-", sizeof rcpt);
        if (strcmp(e->rcpt.user, e->dest.user) ||
            strcmp(e->rcpt.domain, e->dest.domain))
                (void)snprintf(rcpt, sizeof rcpt, "%s@%s",
                    e->rcpt.user, e->rcpt.domain);

        log_info("%s: %s for %016" PRIx64 ": from=<%s@%s>, to=<%s@%s>, "
            "rcpt=<%s>, delay=%s, stat=%s",
            e->type == D_MDA ? "delivery" : "relay",
            prefix,
            e->id, e->sender.user, e->sender.domain,
            e->dest.user, e->dest.domain,
            rcpt,
            duration_to_text(time(NULL) - e->creation),
            status);
}