sm.c   [plain text]

/*
 * jabberd - Jabber Open Source Server
 * Copyright (c) 2002 Jeremie Miller, Thomas Muldowney,
 *                    Ryan Eatmon, Robert Norris
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA02111-1307USA
 */

#include "sm.h"

/** @file sm/sm.c
  * @brief stream / io callbacks
  * @author Robert Norris
  * $Date: 2006/03/14 23:27:28 $
  * $Revision: 1.1 $
  */

/** our master callback */
int sm_sx_callback(sx_t s, sx_event_t e, void *data, void *arg) {
    sm_t sm = (sm_t) arg;
    sx_buf_t buf = (sx_buf_t) data;
    sx_error_t *sxe;
    nad_t nad;
    pkt_t pkt;
    int len, ns, elem, attr;

    switch(e) {
        case event_WANT_READ:
            log_debug(ZONE, "want read");
            mio_read(sm->mio, sm->fd);
            break;

        case event_WANT_WRITE:
            log_debug(ZONE, "want write");
            mio_write(sm->mio, sm->fd);
            break;

        case event_READ:
            log_debug(ZONE, "reading from %d", sm->fd);

            /* do the read */
            len = recv(sm->fd, buf->data, buf->len, 0);

            if(len < 0) {
                if(errno == EWOULDBLOCK || errno == EINTR || errno == EAGAIN) {
                    buf->len = 0;
                    return 0;
                }

                log_write(sm->log, LOG_NOTICE, "[%d] [router] read error: %s (%d)", sm->fd, strerror(errno), errno);

                sx_kill(s);
                
                return -1;
            }

            else if(len == 0) {
                /* they went away */
                sx_kill(s);

                return -1;
            }

            log_debug(ZONE, "read %d bytes", len);

            buf->len = len;

            return len;

        case event_WRITE:
            log_debug(ZONE, "writing to %d", sm->fd);

            len = send(sm->fd, buf->data, buf->len, 0);
            if(len >= 0) {
                log_debug(ZONE, "%d bytes written", len);
                return len;
            }

            if(errno == EWOULDBLOCK || errno == EINTR || errno == EAGAIN)
                return 0;

            log_write(sm->log, LOG_NOTICE, "[%d] [router] write error: %s (%d)", sm->fd, strerror(errno), errno);

            sx_kill(s);

            return -1;

        case event_ERROR:
            sxe = (sx_error_t *) data;
            log_write(sm->log, LOG_NOTICE, "error from router: %s (%s)", sxe->generic, sxe->specific);

            if(sxe->code == SX_ERR_AUTH)
                sx_close(s);

            break;

        case event_STREAM:
            break;

        case event_OPEN:
            log_write(sm->log, LOG_NOTICE, "connection to router established");

            /* reset connection attempts counter */
            sm->retry_left = sm->retry_init;

            nad = nad_new(sm->router->nad_cache);
            ns = nad_add_namespace(nad, uri_COMPONENT, NULL);
            nad_append_elem(nad, ns, "bind", 0);
            nad_append_attr(nad, -1, "name", sm->id);

            log_debug(ZONE, "requesting component bind for '%s'", sm->id);

            sx_nad_write(sm->router, nad);

            break;

        case event_PACKET:
            nad = (nad_t) data;

            /* drop unqualified packets */
            if(NAD_ENS(nad, 0) < 0) {
                nad_free(nad);
                return 0;
            }
            /* watch for the features packet */
            if(s->state == state_STREAM) {
                if(NAD_NURI_L(nad, NAD_ENS(nad, 0)) != strlen(uri_STREAMS) || strncmp(uri_STREAMS, NAD_NURI(nad, NAD_ENS(nad, 0)), strlen(uri_STREAMS)) != 0 || NAD_ENAME_L(nad, 0) != 8 || strncmp("features", NAD_ENAME(nad, 0), 8) != 0) {
                    log_debug(ZONE, "got a non-features packet on an unauth'd stream, dropping");
                    nad_free(nad);
                    return 0;
                }

#ifdef HAVE_SSL
                /* starttls if we can */
                if(sm->sx_ssl != NULL && s->ssf == 0) {
                    ns = nad_find_scoped_namespace(nad, uri_TLS, NULL);
                    if(ns >= 0) {
                        elem = nad_find_elem(nad, 0, ns, "starttls", 1);
                        if(elem >= 0) {
                            if(sx_ssl_client_starttls(sm->sx_ssl, s, NULL) == 0) {
                                nad_free(nad);
                                return 0;
                            }
                            log_write(sm->log, LOG_NOTICE, "unable to establish encrypted session with router");
                        }
                    }
                }
#endif

                /* !!! pull the list of mechanisms, and choose the best one.
                 *     if there isn't an appropriate one, error and bail */

                /* authenticate */
                sx_sasl_auth(sm->sx_sasl, s, "jabberd-router", "DIGEST-MD5", sm->router_user, sm->router_pass);

                nad_free(nad);
                return 0;
            }

            /* watch for the bind response */
            if(s->state == state_OPEN && !sm->online) {
                if(NAD_NURI_L(nad, NAD_ENS(nad, 0)) != strlen(uri_COMPONENT) || strncmp(uri_COMPONENT, NAD_NURI(nad, NAD_ENS(nad, 0)), strlen(uri_COMPONENT)) != 0 || NAD_ENAME_L(nad, 0) != 4 || strncmp("bind", NAD_ENAME(nad, 0), 4)) {
                    log_debug(ZONE, "got a packet from router, but we're not online, dropping");
                    nad_free(nad);
                    return 0;
                }

                /* catch errors */
                attr = nad_find_attr(nad, 0, -1, "error", NULL);
                if(attr >= 0) {
                    log_write(sm->log, LOG_NOTICE, "router refused bind request (%.*s)", NAD_AVAL_L(nad, attr), NAD_AVAL(nad, attr));
                    exit(1);
                }

                log_debug(ZONE, "coming online");

                /* we're online */
                sm->online = sm->started = 1;
                log_write(sm->log, LOG_NOTICE, "ready for sessions", sm->id);

                nad_free(nad);
                return 0;
            }

            log_debug(ZONE, "got a packet");

            pkt = pkt_new(sm, (nad_t) data);
            if(pkt == NULL) {
                log_debug(ZONE, "invalid packet, dropping");

                nad_free(nad);
                return 0;
            }

            /* go */
            dispatch(sm, pkt);

            return 0;

        case event_CLOSED:
            mio_close(sm->mio, sm->fd);
            break;
    }

    return 0;
}

int sm_mio_callback(mio_t m, mio_action_t a, int fd, void *data, void *arg) {
    sm_t sm = (sm_t) arg;
    int nbytes;

    switch(a) {
        case action_READ:
            log_debug(ZONE, "read action on fd %d", fd);

            ioctl(fd, FIONREAD, &nbytes);
            if(nbytes == 0) {
                sx_kill(sm->router);
                return 0;
            }

            return sx_can_read(sm->router);

        case action_WRITE:
            log_debug(ZONE, "write action on fd %d", fd);
            return sx_can_write(sm->router);

        case action_CLOSE:
            log_debug(ZONE, "close action on fd %d", fd);
            log_write(sm->log, LOG_NOTICE, "connection to router closed");

            sm_lost_router = 1;

            /* we're offline */
            sm->online = 0;

            break;

        case action_ACCEPT:
            break;
    }

    return 0;
}

/** this was jutil_timestamp in a former life */
void sm_timestamp(time_t t, char timestamp[18])
{
    struct tm *gm = gmtime(&t);

    snprintf(timestamp, 18, "%d%02d%02dT%02d:%02d:%02d", 1900 + gm->tm_year,
             gm->tm_mon + 1, gm->tm_mday, gm->tm_hour, gm->tm_min, gm->tm_sec);

    return;
}

/** send a new action route */
void sm_c2s_action(sess_t dest, char *action, char *target) {
    nad_t nad;
    int rns, sns;

    nad = nad_new(dest->user->sm->router->nad_cache);

    rns = nad_add_namespace(nad, uri_COMPONENT, NULL);
    nad_append_elem(nad, rns, "route", 0);

    nad_append_attr(nad, -1, "to", dest->c2s);
    nad_append_attr(nad, -1, "from", dest->user->sm->id);

    sns = nad_add_namespace(nad, uri_SESSION, "sc");
    nad_append_elem(nad, sns, "session", 1);

    if(dest->c2s_id[0] != '\0')
        nad_append_attr(nad, sns, "c2s", dest->c2s_id);
    if(dest->sm_id[0] != '\0')
        nad_append_attr(nad, sns, "sm", dest->sm_id);

    nad_append_attr(nad, -1, "action", action);
    if(target != NULL)
        nad_append_attr(nad, -1, "target", target);

    log_debug(ZONE, "routing nad to %s from %s c2s %s s2s %s action %s target %s", dest->c2s, dest->user->sm->id, dest->c2s_id, dest->sm_id, action, target);

    sx_nad_write(dest->user->sm->router, nad);
}

/** this is gratuitous, but apache gets one, so why not? */
void sm_signature(sm_t sm, char *str) {
    if(sm->siglen == 0) {
        snprintf(&sm->signature[sm->siglen], 2048 - sm->siglen, "%s", str);
        sm->siglen += strlen(str);
    } else {
        snprintf(&sm->signature[sm->siglen], 2048 - sm->siglen, " %s", str);
        sm->siglen += strlen(str) + 1;
    }
}