Beispiel #1
0
/** process handshake packets from the client */
static int _sx_ack_process(sx_t s, sx_plugin_t p, nad_t nad) {
    int attr;

    /* not interested if we're not a server */
    if(s->type != type_SERVER)
        return 1;

    /* only want ack packets */
    if((NAD_ENS(nad, 0) < 0 || NAD_NURI_L(nad, NAD_ENS(nad, 0)) != strlen(uri_ACK) || strncmp(NAD_NURI(nad, NAD_ENS(nad, 0)), uri_ACK, strlen(uri_ACK)) != 0))
        return 1;

    /* pings */
    if(NAD_ENAME_L(nad, 0) == 4 && strncmp(NAD_ENAME(nad, 0), "ping", 4) == 0) {
        jqueue_push(s->wbufq, _sx_buffer_new("<ack:pong/>", 11, NULL, NULL), 0);
        s->want_write = 1;

        /* handled the packet */
        nad_free(nad);
        return 0;
    }

    /* enable only when authenticated */
    if(s->state == state_OPEN && NAD_ENAME_L(nad, 0) == 6 && strncmp(NAD_ENAME(nad, 0), "enable", 6) == 0) {
        jqueue_push(s->wbufq, _sx_buffer_new("<ack:enabled/>", 14, NULL, NULL), 254);
        s->want_write = 1;

        s->plugin_data[p->index] = (void *) 1;

        /* handled the packet */
        nad_free(nad);
        return 0;
    }

    /* 'r' or 'a' when enabled */
    if(s->plugin_data[p->index] != NULL && NAD_ENAME_L(nad, 0) == 1 && (strncmp(NAD_ENAME(nad, 0), "r", 1) == 0 || strncmp(NAD_ENAME(nad, 0), "a", 1) == 0) ) {
        attr = nad_find_attr(nad, 0, -1, "c", NULL);
        if(attr >= 0) {
            char *buf = (char *) malloc(sizeof(char) * (NAD_AVAL_L(nad, attr) + 13 + 1));
            snprintf(buf, NAD_AVAL_L(nad, attr) + 13 + 1, "<ack:a b='%.*s'/>", NAD_AVAL_L(nad, attr), NAD_AVAL(nad, attr));
            jqueue_push(s->wbufq, _sx_buffer_new(buf, NAD_AVAL_L(nad, attr) + 13, NULL, NULL), 255);
            free(buf);
            s->want_write = 1;
        }
        
        /* handled the packet */
        nad_free(nad);
        return 0;
    }

    _sx_debug(ZONE, "unhandled ack namespace element '%.*s', dropping packet", NAD_ENAME_L(nad, 0), NAD_ENAME(nad, 0));
    nad_free(nad);
    return 0;
}
Beispiel #2
0
static int _router_sx_callback(sx_t s, sx_event_t e, void *data, void *arg) {
    component_t comp = (component_t) arg;
    sx_buf_t buf = (sx_buf_t) data;
    int rlen, len, attr, ns, sns, n;
    sx_error_t *sxe;
    nad_t nad;
    struct jid_st sto, sfrom;
    jid_static_buf sto_buf, sfrom_buf;
    jid_t to, from;
    alias_t alias;

    /* init static jid */
    jid_static(&sto,&sto_buf);
    jid_static(&sfrom,&sfrom_buf);

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

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

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

            /* check rate limits */
            if(comp->rate != NULL) {
                if(rate_check(comp->rate) == 0) {

                    /* inform the app if we haven't already */
                    if(!comp->rate_log) {
                        log_write(comp->r->log, LOG_NOTICE, "[%s, port=%d] is being byte rate limited", comp->ip, comp->port);

                        comp->rate_log = 1;
                    }

                    log_debug(ZONE, "%d is throttled, delaying read", comp->fd->fd);

                    buf->len = 0;
                    return 0;
                }

                /* find out how much we can have */
                rlen = rate_left(comp->rate);
                if(rlen > buf->len)
                    rlen = buf->len;
            }

            /* no limit, just read as much as we can */
            else
                rlen = buf->len;
            
            /* do the read */
            len = recv(comp->fd->fd, buf->data, rlen, 0);

            /* update rate limits */
            if(comp->rate != NULL && len > 0) {
                comp->rate_log = 0;
                rate_add(comp->rate, len);
            }

            if(len < 0) {
                if(MIO_WOULDBLOCK) {
                    buf->len = 0;
                    return 0;
                }

                log_debug(ZONE, "read failed: %s", strerror(errno));

                sx_kill(comp->s);
                
                return -1;
            }

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

                return -1;
            }

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

            buf->len = len;

            return len;

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

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

            if(MIO_WOULDBLOCK)
                return 0;

            log_debug(ZONE, "write failed: %s", strerror(errno));
        
            sx_kill(comp->s);
        
            return -1;

        case event_ERROR:
            sxe = (sx_error_t *) data;
            log_write(comp->r->log, LOG_NOTICE, "[%s, port=%d] error: %s (%s)", comp->ip, comp->port, sxe->generic, sxe->specific);

            break;

        case event_STREAM:
            
            /* legacy check */
            if(s->ns == NULL || strcmp("jabber:component:accept", s->ns) != 0)
                return 0;

            /* component, old skool */
            comp->legacy = 1;

            /* enabled? */
            if(comp->r->local_secret == NULL) {
                sx_error(s, stream_err_INVALID_NAMESPACE, "support for legacy components not available");      /* !!! correct error? */
                sx_close(s);
                return 0;
            }
            
            /* sanity */
            if(s->req_to == NULL) {
                sx_error(s, stream_err_HOST_UNKNOWN, "no 'to' attribute on stream header");
                sx_close(s);
                return 0;
            }

            break;

        case event_OPEN:
            
            log_write(comp->r->log, LOG_NOTICE, "[%s, port=%d] authenticated as %s", comp->ip, comp->port, comp->s->auth_id);

            /* make a route for legacy components */
            if(comp->legacy) {
                for(alias = comp->r->aliases; alias != NULL; alias = alias->next)
                    if(strcmp(alias->name, s->req_to) == 0) {
                        sx_error(s, stream_err_HOST_UNKNOWN, "requested name is aliased");   /* !!! correct error? */
                        sx_close(s);
                        return 0;
                    }


                n = _route_add(comp->r->routes, s->req_to, comp, route_MULTI_FROM);
                xhash_put(comp->routes, pstrdup(xhash_pool(comp->routes), s->req_to), (void *) comp);

                if(n>1)
                    log_write(comp->r->log, LOG_NOTICE, "[%s]:%d online (bound to %s, port %d)", s->req_to, n, comp->ip, comp->port);
                else
                    log_write(comp->r->log, LOG_NOTICE, "[%s] online (bound to %s, port %d)", s->req_to, comp->ip, comp->port);

                /* advertise the name */
                _router_advertise(comp->r, s->req_to, comp, 0);

                /* this is a legacy component, so we don't tell it about other routes */

                /* bind aliases */
                for(alias = comp->r->aliases; alias != NULL; alias = alias->next) {
                    if(strcmp(alias->target, s->req_to) == 0) {
                        _route_add(comp->r->routes, alias->name, comp, route_MULTI_FROM);
                        xhash_put(comp->routes, pstrdup(xhash_pool(comp->routes), alias->name), (void *) comp);
            
                        log_write(comp->r->log, LOG_NOTICE, "[%s] online (alias of '%s', bound to %s, port %d)", alias->name, s->req_to, comp->ip, comp->port);

                        /* advertise name */
                        _router_advertise(comp->r, alias->name, comp, 0);
                    }
                }
            }

            break;

        case event_PACKET:
            nad = (nad_t) data;

            /* preauth */
            if(comp->s->state == state_STREAM) {
                /* non-legacy components can't do anything before auth */
                if(!comp->legacy) {
                    log_debug(ZONE, "stream is preauth, dropping packet");
                    nad_free(nad);
                    return 0;
                }

                /* watch for handshake requests */
                if(NAD_ENAME_L(nad, 0) != 9 || strncmp("handshake", NAD_ENAME(nad, 0), NAD_ENAME_L(nad, 0)) != 0) { 
                    log_debug(ZONE, "unknown preauth packet %.*s, dropping", NAD_ENAME_L(nad, 0), NAD_ENAME(nad, 0));

                    nad_free(nad);
                    return 0;
                }

                /* process incoming handshakes */
                _router_process_handshake(comp, nad);

                return 0;
            }

            /* legacy processing */
            if(comp->legacy) {
                log_debug(ZONE, "packet from legacy component, munging it");

                attr = nad_find_attr(nad, 0, -1, "to", NULL);
                if(attr < 0 || (to = jid_reset(&sto, NAD_AVAL(nad, attr), NAD_AVAL_L(nad, attr))) == NULL) {
                    log_debug(ZONE, "invalid or missing 'to' address on legacy packet, dropping it");
                    nad_free(nad);
                    return 0;
                }

                attr = nad_find_attr(nad, 0, -1, "from", NULL);
                if(attr < 0 || (from = jid_reset(&sfrom, NAD_AVAL(nad, attr), NAD_AVAL_L(nad, attr))) == NULL) {
                    log_debug(ZONE, "invalid or missing 'from' address on legacy packet, dropping it");
                    nad_free(nad);
                    return 0;
                }

                /* rewrite component packets into client packets */
                ns = nad_find_namespace(nad, 0, "jabber:component:accept", NULL);
                if(ns >= 0) {
                    if(nad->elems[0].ns == ns)
                        nad->elems[0].ns = nad->nss[nad->elems[0].ns].next;
                    else {
                        for(sns = nad->elems[0].ns; sns >= 0 && nad->nss[sns].next != ns; sns = nad->nss[sns].next);
                        nad->nss[sns].next = nad->nss[nad->nss[sns].next].next;
                    }
                }

                ns = nad_find_namespace(nad, 0, uri_CLIENT, NULL);
                if(ns < 0) {
                    ns = nad_add_namespace(nad, uri_CLIENT, NULL);
                    nad->scope = -1;
                    nad->nss[ns].next = nad->elems[0].ns;
                    nad->elems[0].ns = ns;
                }
                nad->elems[0].my_ns = ns;

                /* wrap up the packet */
                ns = nad_add_namespace(nad, uri_COMPONENT, NULL);

                nad_wrap_elem(nad, 0, ns, "route");

                nad_set_attr(nad, 0, -1, "to", to->domain, 0);
                nad_set_attr(nad, 0, -1, "from", from->domain, 0);
            }

            /* top element must be router scoped */
            if(NAD_ENS(nad, 0) < 0 || 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) {
                log_debug(ZONE, "invalid packet namespace, dropping");
                nad_free(nad);
                return 0;
            }

            /* bind a name to this component */
            if(NAD_ENAME_L(nad, 0) == 4 && strncmp("bind", NAD_ENAME(nad, 0), 4) == 0) {
                _router_process_bind(comp, nad);
                return 0;
            }

            /* unbind a name from this component */
            if(NAD_ENAME_L(nad, 0) == 6 && strncmp("unbind", NAD_ENAME(nad, 0), 6) == 0) {
                _router_process_unbind(comp, nad);
                return 0;
            }

            /* route packets */
            if(NAD_ENAME_L(nad, 0) == 5 && strncmp("route", NAD_ENAME(nad, 0), 5) == 0) {
                _router_process_route(comp, nad);
                return 0;
            }

            /* throttle packets */
            if(NAD_ENAME_L(nad, 0) == 8 && strncmp("throttle", NAD_ENAME(nad, 0), 8) == 0) {
                _router_process_throttle(comp, nad);
                return 0;
            }

            log_debug(ZONE, "unknown packet, dropping");

            nad_free(nad);
            return 0;

        case event_CLOSED:
        {
            /* close comp->fd by putting it in closefd ... unless it is already there */
            _jqueue_node_t n;
            for (n = comp->r->closefd->front; n != NULL; n = n->prev)
                if (n->data == comp->fd) break;
            if (!n) jqueue_push(comp->r->closefd, (void *) comp->fd, 0 /*priority*/);
            return 0;
        }
    }

    return 0;
}
Beispiel #3
0
static void _router_process_route(component_t comp, nad_t nad) {
    int atype, ato, afrom;
    unsigned int dest;
    struct jid_st sto, sfrom;
    jid_static_buf sto_buf, sfrom_buf;
    jid_t to = NULL, from = NULL;
    routes_t targets;
    component_t target;
    union xhashv xhv;

    /* init static jid */
    jid_static(&sto,&sto_buf);
    jid_static(&sfrom,&sfrom_buf);

    if(nad_find_attr(nad, 0, -1, "error", NULL) >= 0) {
        log_debug(ZONE, "dropping error packet, trying to avoid loops");
        nad_free(nad);
        return;
    }

    atype = nad_find_attr(nad, 0, -1, "type", NULL);
    ato = nad_find_attr(nad, 0, -1, "to", NULL);
    afrom = nad_find_attr(nad, 0, -1, "from", NULL);

    if(ato >= 0) to = jid_reset(&sto, NAD_AVAL(nad, ato), NAD_AVAL_L(nad, ato));
    if(afrom >= 0) from = jid_reset(&sfrom, NAD_AVAL(nad, afrom), NAD_AVAL_L(nad, afrom));

    /* unicast */
    if(atype < 0) {
        if(to == NULL || from == NULL) {
            log_debug(ZONE, "unicast route with missing or invalid to or from, bouncing");
            nad_set_attr(nad, 0, -1, "error", "400", 3);
            _router_comp_write(comp, nad);
            return;
        }
        
        log_debug(ZONE, "unicast route from %s to %s", from->domain, to->domain);

        /* check the from */
        if(xhash_get(comp->routes, from->domain) == NULL) {
            log_write(comp->r->log, LOG_NOTICE, "[%s, port=%d] tried to send a packet from '%s', but that name is not bound to this component", comp->ip, comp->port, from->domain);
            nad_set_attr(nad, 0, -1, "error", "401", 3);
            _router_comp_write(comp, nad);
            return;
        }

        /* filter it */
        if(comp->r->filter != NULL) {
            int ret = filter_packet(comp->r, nad);
            if(ret == stanza_err_REDIRECT) {
                ato = nad_find_attr(nad, 0, -1, "to", NULL);
                if(ato >= 0) to = jid_reset(&sto, NAD_AVAL(nad, ato), NAD_AVAL_L(nad, ato));
            }
            else if(ret > 0) {
                log_debug(ZONE, "packet filtered out: %s (%s)", _stanza_errors[ret - stanza_err_BAD_REQUEST].name, _stanza_errors[ret - stanza_err_BAD_REQUEST].code);
                nad_set_attr(nad, 0, -1, "error", _stanza_errors[ret - stanza_err_BAD_REQUEST].code, 3);
                _router_comp_write(comp, nad);
                return;
            }
        }

        /* find a target */
        targets = xhash_get(comp->r->routes, to->domain);
        if(targets == NULL) {
            if(comp->r->default_route != NULL && strcmp(from->domain, comp->r->default_route) == 0) {
                log_debug(ZONE, "%s is unbound, bouncing", from->domain);
                nad_set_attr(nad, 0, -1, "error", "404", 3);
                _router_comp_write(comp, nad);
                return;
            }
            targets = xhash_get(comp->r->routes, comp->r->default_route);
        }

        if(targets == NULL) {
            log_debug(ZONE, "%s is unbound, and no default route, bouncing", to->domain);
            nad_set_attr(nad, 0, -1, "error", "404", 3);
            _router_comp_write(comp, nad);
            return;
        }

        /* copy to any log sinks */
        if(xhash_count(comp->r->log_sinks) > 0)
            xhash_walk(comp->r->log_sinks, _router_route_log_sink, (void *) nad);

        /* get route candidate */
        if(targets->ncomp == 1) {
            dest = 0;
        }
        else {
            switch(targets->rtype) {
                case route_MULTI_TO:
                    ato = nad_find_attr(nad, 1, -1, "to", NULL);
                    if(ato >= 0) to = jid_reset(&sto, NAD_AVAL(nad, ato), NAD_AVAL_L(nad, ato));
                    else {
                        ato = nad_find_attr(nad, 1, -1, "target", NULL);
                        if(ato >= 0) to = jid_reset(&sto, NAD_AVAL(nad, ato), NAD_AVAL_L(nad, ato));
                        else {
                            const char *out; int len;
                            nad_print(nad, 0, &out, &len);
                            log_write(comp->r->log, LOG_ERR, "Cannot get destination for multiple route: %.*s", len, out);
                        }
                    }
                    break;
                case route_MULTI_FROM:
                    ato = nad_find_attr(nad, 1, -1, "from", NULL);
                    if(ato >= 0) to = jid_reset(&sto, NAD_AVAL(nad, ato), NAD_AVAL_L(nad, ato));
                    else {
                        const char *out; int len;
                        nad_print(nad, 0, &out, &len);
                        log_write(comp->r->log, LOG_ERR, "Cannot get source for multiple route: %.*s", len, out);
                    }
                    break;
                default:
                    log_write(comp->r->log, LOG_ERR, "Multiple components bound to single component route '%s'", targets->name);
                    /* simulate no 'to' info in this case */
            }
            if(to->node == NULL || strlen(to->node) == 0) {
                /* no node in destination JID - going random */
                dest = rand();
                log_debug(ZONE, "randomized to %u %% %d = %d", dest, targets->ncomp, dest % targets->ncomp);
            }
            else {
                /* use JID hash */
                unsigned char hashval[20];
                unsigned int *val;
                int i;
                
                shahash_raw(jid_user(to), hashval);
                
                val = (unsigned int *) hashval;
                dest = *val;
                for(i=1; i < 20 / (sizeof(unsigned int)/sizeof(unsigned char)); i++, val++) {
                    dest ^= *val;
                }
                dest >>= 2;

                log_debug(ZONE, "JID %s hashed to %u %% %d = %d", jid_user(to), dest, targets->ncomp, dest % targets->ncomp);

                /* jid_user() calls jid_expand() which may allocate some memory in _user and _full */
                if (to->_user != NULL )
                    free(to->_user);
                if (to->_full != NULL )
                    free(to->_full);
            }
            dest = dest % targets->ncomp;
        }

        target = targets->comp[dest];

        /* push it out */
        log_debug(ZONE, "writing route for '%s'*%u to %s, port %d", to->domain, dest+1, target->ip, target->port);

        /* if logging enabled, log messages that match our criteria */
        if (comp->r->message_logging_enabled && comp->r->message_logging_file != NULL) {
            int attr_msg_to;
            int attr_msg_from;
            int attr_route_to;
            int attr_route_from;
            jid_t jid_msg_from = NULL;
            jid_t jid_msg_to = NULL;
            jid_t jid_route_from = NULL;
            jid_t jid_route_to = NULL;

            if ((NAD_ENAME_L(nad, 1) == 7 && strncmp("message", NAD_ENAME(nad, 1), 7) == 0) &&		// has a "message" element 
                ((attr_route_from = nad_find_attr(nad, 0, -1, "from", NULL)) >= 0) &&
                ((attr_route_to = nad_find_attr(nad, 0, -1, "to", NULL)) >= 0) &&
                ((strncmp(NAD_AVAL(nad, attr_route_to), "c2s", 3)) != 0) &&							// ignore messages to "c2s" or we'd have dups
                ((jid_route_from = jid_new(NAD_AVAL(nad, attr_route_from), NAD_AVAL_L(nad, attr_route_from))) != NULL) &&	// has valid JID source in route
                ((jid_route_to = jid_new(NAD_AVAL(nad, attr_route_to), NAD_AVAL_L(nad, attr_route_to))) != NULL) &&		// has valid JID destination in route
                ((attr_msg_from = nad_find_attr(nad, 1, -1, "from", NULL)) >= 0) &&
                ((attr_msg_to = nad_find_attr(nad, 1, -1, "to", NULL)) >= 0) &&
                ((jid_msg_from = jid_new(NAD_AVAL(nad, attr_msg_from), NAD_AVAL_L(nad, attr_msg_from))) != NULL) &&	// has valid JID source in message 
                ((jid_msg_to = jid_new(NAD_AVAL(nad, attr_msg_to), NAD_AVAL_L(nad, attr_msg_to))) != NULL))			// has valid JID dest in message
            {
                message_log(nad, comp->r, jid_full(jid_msg_from), jid_full(jid_msg_to));
            }
            if (jid_msg_from != NULL)
                jid_free(jid_msg_from);
            if (jid_msg_to != NULL)
                jid_free(jid_msg_to);
            if (jid_route_from != NULL)
                jid_free(jid_route_from);
            if (jid_route_to != NULL)
                jid_free(jid_route_to);
        }

        _router_comp_write(target, nad);

        return;
    }

    /* broadcast */
    if(NAD_AVAL_L(nad, atype) == 9 && strncmp("broadcast", NAD_AVAL(nad, atype), 9) == 0) {
        if(from == NULL) {
            log_debug(ZONE, "broadcast route with missing or invalid from, bouncing");
            nad_set_attr(nad, 0, -1, "error", "400", 3);
            _router_comp_write(comp, nad);
            return;
        }
        
        log_debug(ZONE, "broadcast route from %s", from->domain);

        /* check the from */
        if(xhash_get(comp->routes, from->domain) == NULL) {
            log_write(comp->r->log, LOG_NOTICE, "[%s, port=%d] tried to send a packet from '%s', but that name is not bound to this component", comp->ip, comp->port, from->domain);
            nad_set_attr(nad, 0, -1, "error", "401", 3);
            _router_comp_write(comp, nad);
            return;
        }

        /* loop the components and distribute */
        if(xhash_iter_first(comp->r->components))
            do {
                xhv.comp_val = &target;
                xhash_iter_get(comp->r->components, NULL, NULL, xhv.val);

                if(target != comp) {
                    log_debug(ZONE, "writing broadcast to %s, port %d", target->ip, target->port);

                    _router_comp_write(target, nad_copy(nad));
                }
            } while(xhash_iter_next(comp->r->components));

        nad_free(nad);

        return;
    }

    log_debug(ZONE, "unknown route type '%.*s', dropping", NAD_AVAL_L(nad, atype), NAD_AVAL(nad, atype));

    nad_free(nad);
}
Beispiel #4
0
int message_log(nad_t nad, router_t r, const char *msg_from, const char *msg_to)
{
    time_t t;
    char *time_pos;
    int time_sz;
    struct stat filestat;
    FILE *message_file;
    short int new_msg_file = 0;
    int i;
    int nad_body_len = 0;
    const char *nad_body_start = 0;
    int body_count;
    const char *nad_body = NULL;
    char body[MAX_MESSAGE*2];

    assert((int) (nad != NULL));

    /* timestamp */
    t = time(NULL);
    time_pos = ctime(&t);
    time_sz = strlen(time_pos);
    /* chop off the \n */
    time_pos[time_sz-1]=' ';

    // Find the message body
    for (i = 0; NAD_ENAME_L(nad, i) > 0; i++)
    {
        if((NAD_ENAME_L(nad, i) == 4) && (strncmp("body", NAD_ENAME(nad, i), 4) == 0))
        {
            nad_body_len = NAD_CDATA_L(nad, i);
            if (nad_body_len > 0) {
                nad_body = NAD_CDATA(nad, i);
            } else {
                log_write(r->log, LOG_NOTICE, "message_log received a message with empty body");
                return 0;
            }
            break;
        }
    }

    // Don't log anything if we found no NAD body
    if (nad_body == NULL) {
        return 0;
    }

    // Store original pointer address so that we know when to stop iterating through nad_body
    nad_body_start = nad_body;

    // replace line endings with "\n"
    for (body_count = 0; (nad_body < nad_body_start + nad_body_len) && (body_count < (MAX_MESSAGE*2)-3); nad_body++) {
        if (*nad_body == '\n') {
            body[body_count++] = '\\';
            body[body_count++] = 'n';
        } else {
            body[body_count++] = *nad_body;
        }
    }
    body[body_count] = '\0';

    // Log our message
    umask((mode_t) 0077);
    if (stat(r->message_logging_file, &filestat)) {
        new_msg_file = 1;
    }

    if ((message_file = fopen(r->message_logging_file, "a")) == NULL)
    {
        log_write(r->log, LOG_ERR, "Unable to open message log for writing: %s", strerror(errno));
        return 1;
    }

    if (new_msg_file) {
        if (! fprintf(message_file, "# This message log is created by the jabberd router.\n"))
        {
            log_write(r->log, LOG_ERR, "Unable to write to message log: %s", strerror(errno));
            return 1;
        }
        fprintf(message_file, "# See router.xml for logging options.\n");
        fprintf(message_file, "# Format: (Date)<tab>(From JID)<tab>(To JID)<tab>(Message Body)<line end>\n");
    }

    if (! fprintf(message_file, "%s\t%s\t%s\t%s\n", time_pos, msg_from, msg_to, body))
    {
        log_write(r->log, LOG_ERR, "Unable to write to message log: %s", strerror(errno));
        return 1;
    }

    fclose(message_file);

    return 0;
}
Beispiel #5
0
Datei: in.c Projekt: zipo/zipo
static int _in_sx_callback(sx_t s, sx_event_t e, void *data, void *arg) {
    conn_t in = (conn_t) arg;
    sx_buf_t buf = (sx_buf_t) data;
    int len;
    sx_error_t *sxe;
    nad_t nad;
    char ipport[INET6_ADDRSTRLEN + 17];

    switch(e) {
        case event_WANT_READ:
            log_debug(ZONE, "want read");
            mio_read(in->s2s->mio, in->fd);
            break;

        case event_WANT_WRITE:
            log_debug(ZONE, "want write");
            mio_write(in->s2s->mio, in->fd);
            break;

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

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

            if(len < 0) {
                if(MIO_WOULDBLOCK) {
                    buf->len = 0;
                    return 0;
                }

                log_write(in->s2s->log, LOG_NOTICE, "[%d] [%s, port=%d] read error: %s (%d)", in->fd->fd, in->ip, in->port, MIO_STRERROR(MIO_ERROR), MIO_ERROR);

                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", in->fd->fd);

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

            if(MIO_WOULDBLOCK)
                return 0;

            log_write(in->s2s->log, LOG_NOTICE, "[%d] [%s, port=%d] write error: %s (%d)", in->fd->fd, in->ip, in->port, MIO_STRERROR(MIO_ERROR), MIO_ERROR);

            sx_kill(s);

            return -1;

        case event_ERROR:
            sxe = (sx_error_t *) data;
            log_write(in->s2s->log, LOG_NOTICE, "[%d] [%s, port=%d] error: %s (%s)", in->fd->fd, in->ip, in->port, sxe->generic, sxe->specific);

            break;

        case event_STREAM:
        case event_OPEN:

            log_debug(ZONE, "STREAM or OPEN event from %s port %d (id %s)", in->ip, in->port, s->id);

            /* first time, bring them online */
            if ((!in->online)||(strcmp(in->key,s->id)!=0)) { 
                log_write(in->s2s->log, LOG_NOTICE, "[%d] [%s, port=%d] incoming stream online (id %s)", in->fd->fd, in->ip, in->port, s->id);

                in->online = 1;

                /* record the id */
                if (in->key != NULL) {
                   log_debug(ZONE,"adding new SSL stream id %s for stream id %s", s->id, in->key);

                   /* remove the initial (non-SSL) stream id from the in connections hash */
                   xhash_zap(in->s2s->in, in->key);
                   free(in->key);
                }

                in->key = strdup(s->id);

                /* track it - add to open streams hash and remove from new connections hash */
                xhash_put(in->s2s->in, in->key, (void *) in);

                snprintf(ipport, INET6_ADDRSTRLEN + 16, "%s/%d", in->ip, in->port);
                xhash_zap(in->s2s->in_accept, ipport);
            }  

            break;

        case event_PACKET:
            /* we're counting packets */
            in->packet_count++;
            in->s2s->packet_count++;

            nad = (nad_t) data;

            /* update last packet timestamp */
            in->last_packet = time(NULL);

            /* dialback packets */
            if(NAD_NURI_L(nad, NAD_ENS(nad, 0)) == strlen(uri_DIALBACK) && strncmp(uri_DIALBACK, NAD_NURI(nad, NAD_ENS(nad, 0)), strlen(uri_DIALBACK)) == 0) {
                /* only result and verify mean anything */
                if(NAD_ENAME_L(nad, 0) == 6) {
                    if(strncmp("result", NAD_ENAME(nad, 0), 6) == 0) {
                        _in_result(in, nad);
                        return 0;
                    }

                    if(strncmp("verify", NAD_ENAME(nad, 0), 6) == 0) {
                        _in_verify(in, nad);
                        return 0;
                    }
                }
                
                log_debug(ZONE, "unknown dialback packet, dropping it");

                nad_free(nad);
                return 0;
            }

            /*
             * not dialback, so it has to be a normal-ish jabber packet:
             *  - jabber:client or jabber:server
             *  - message, presence or iq
             *  - has to and from attributes
             */

            if(!(
                 /* must be jabber:client or jabber:server */
                 NAD_ENS(nad, 0) >= 0 &&
                 ((NAD_NURI_L(nad, NAD_ENS(nad, 0)) == strlen(uri_CLIENT) && strncmp(uri_CLIENT, NAD_NURI(nad, NAD_ENS(nad, 0)), strlen(uri_CLIENT)) == 0) ||
                 (NAD_NURI_L(nad, NAD_ENS(nad, 0)) == strlen(uri_SERVER) && strncmp(uri_SERVER, NAD_NURI(nad, NAD_ENS(nad, 0)), strlen(uri_SERVER)) == 0)) && (
                    /* can be message */
                    (NAD_ENAME_L(nad, 0) == 7 && strncmp("message", NAD_ENAME(nad, 0), 7) == 0) ||
                    /* or presence */
                    (NAD_ENAME_L(nad, 0) == 8 && strncmp("presence", NAD_ENAME(nad, 0), 8) == 0) ||
                    /* or iq */
                    (NAD_ENAME_L(nad, 0) == 2 && strncmp("iq", NAD_ENAME(nad, 0), 2) == 0)
                 ) &&
                 /* to and from required */
                 nad_find_attr(nad, 0, -1, "to", NULL) >= 0 && nad_find_attr(nad, 0, -1, "from", NULL) >= 0
               )) {
                log_debug(ZONE, "they sent us a non-jabber looking packet, dropping it");
                nad_free(nad);
                return 0;
            }

            _in_packet(in, nad);
            return 0;

        case event_CLOSED:
            mio_close(in->s2s->mio, in->fd);
            return -1;
    }

    return 0;
}
Beispiel #6
0
/** 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;
    char *domain;

    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->fd);

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

            if (len < 0) {
                if (MIO_WOULDBLOCK) {
                    buf->len = 0;
                    return 0;
                }

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

                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->fd);

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

            if (MIO_WOULDBLOCK)
                return 0;

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

            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");

            /* set connection attempts counter */
            sm->retry_left = sm->retry_lost;

            nad = nad_new();
            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);
            
            if(xhash_iter_first(sm->hosts))
            do {
                xhash_iter_get(sm->hosts, (void *) &domain, &len, NULL);

                /* skip already requested SM id */
                if (strlen(sm->id) == len && strncmp(sm->id, domain, len) == 0)
                    continue;

                nad = nad_new();
                ns = nad_add_namespace(nad, uri_COMPONENT, NULL);
                elem = nad_append_elem(nad, ns, "bind", 0);
                nad_set_attr(nad, elem, -1, "name", domain, len);
                nad_append_attr(nad, -1, "multi", "to");
                log_debug(ZONE, "requesting domain bind for '%.*s'", len, domain);
                sx_nad_write(sm->router, nad);
            } while(xhash_iter_next(sm->hosts));
            
            sm_update_host = 1;
            
            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, 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, "%s ready for sessions", sm->id);

                nad_free(nad);
                return 0;
            }

            log_debug(ZONE, "got a packet");

            pkt = pkt_new(sm, nad);
            if (pkt == NULL) {
                log_debug(ZONE, "invalid packet, dropping");
                return 0;
            }

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

            return 0;

        case event_CLOSED:
            mio_close(sm->mio, sm->fd);
            sm->fd = NULL;
            return -1;
    }

    return 0;
}
Beispiel #7
0
/**
 * processor for iq:auth and iq:register packets
 * return 0 if handled, 1 if not handled
 */
int authreg_process(c2s_t c2s, sess_t sess, nad_t nad) {
    int ns, query, type, authreg = -1, getset = -1;

    /* need iq */
    if(NAD_ENAME_L(nad, 0) != 2 || strncmp("iq", NAD_ENAME(nad, 0), 2) != 0)
        return 1;

    /* only want auth or register packets */
    if((ns = nad_find_scoped_namespace(nad, uri_AUTH, NULL)) >= 0 && (query = nad_find_elem(nad, 0, ns, "query", 1)) >= 0)
        authreg = 0;
    else if((ns = nad_find_scoped_namespace(nad, uri_REGISTER, NULL)) >= 0 && (query = nad_find_elem(nad, 0, ns, "query", 1)) >= 0)
        authreg = 1;
    else
        return 1;

    /* if its to someone else, pass it */
    if(nad_find_attr(nad, 0, -1, "to", NULL) >= 0 && nad_find_attr(nad, 0, -1, "to", sess->s->req_to) < 0)
        return 1;

    /* need a type */
    if((type = nad_find_attr(nad, 0, -1, "type", NULL)) < 0 || NAD_AVAL_L(nad, type) != 3)
    {
        sx_nad_write(sess->s, stanza_tofrom(stanza_error(nad, 0, stanza_err_BAD_REQUEST), 0));
        return 0;
    }

    /* get or set? */
    if(strncmp("get", NAD_AVAL(nad, type), NAD_AVAL_L(nad, type)) == 0)
        getset = 0;
    else if(strncmp("set", NAD_AVAL(nad, type), NAD_AVAL_L(nad, type)) == 0)
        getset = 1;
    else
    {
        sx_nad_write(sess->s, stanza_tofrom(stanza_error(nad, 0, stanza_err_BAD_REQUEST), 0));
        return 0;
    }

    /* hand to the correct handler */
    if(authreg == 0) {
        /* can't do iq:auth after sasl auth */
        if(sess->sasl_authd) {
            sx_nad_write(sess->s, stanza_tofrom(stanza_error(nad, 0, stanza_err_NOT_ALLOWED), 0));
            return 0;
        }

        if(getset == 0) {
            log_debug(ZONE, "auth get");
            _authreg_auth_get(c2s, sess, nad);
        } else if(getset == 1) {
            log_debug(ZONE, "auth set");
            _authreg_auth_set(c2s, sess, nad);
        }
    }

    if(authreg == 1) {
        if(getset == 0) {
            log_debug(ZONE, "register get");
            _authreg_register_get(c2s, sess, nad);
        } else if(getset == 1) {
            log_debug(ZONE, "register set");
            _authreg_register_set(c2s, sess, nad);
        }
    }

    /* handled */
    return 0;
}
Beispiel #8
0
/** handler for read data */
void _sx_process_read(sx_t s, sx_buf_t buf) {
    sx_error_t sxe;
    nad_t nad;
    char *errstring;
    int i;
    int ns, elem;

    /* Note that buf->len can validly be 0 here, if we got data from
       the socket but the plugin didn't return anything to us (e.g. a
       SSL packet was split across a tcp segment boundary) */

    /* count bytes parsed */
    s->pbytes += buf->len;

    /* parse it */
    if(XML_Parse(s->expat, buf->data, buf->len, 0) == 0) {
        /* only report error we haven't already */
        if(!s->fail) {
            /* parse error */
            errstring = (char *) XML_ErrorString(XML_GetErrorCode(s->expat));

            _sx_debug(ZONE, "XML parse error: %s, character %d: %.*s",
                      errstring, XML_GetCurrentByteIndex(s->expat) - s->tbytes, buf->len, buf->data);
            _sx_gen_error(sxe, SX_ERR_XML_PARSE, "XML parse error", errstring);
            _sx_event(s, event_ERROR, (void *) &sxe);

            _sx_error(s, stream_err_XML_NOT_WELL_FORMED, errstring);
            _sx_close(s);

            _sx_buffer_free(buf);

            return;
        }

        /* !!! is this the right thing to do? we should probably set
         *     s->fail and let the code further down handle it. */
        _sx_buffer_free(buf);

        return;
    }

    /* check if the stanza size limit is exceeded (it wasn't reset by parser) */
    if(s->rbytesmax && s->pbytes > s->rbytesmax) {
        /* parse error */
        _sx_debug(ZONE, "maximum stanza size (%d) exceeded by reading %d bytes", s->rbytesmax, s->pbytes);

        errstring = (char *) XML_ErrorString(XML_GetErrorCode(s->expat));

        _sx_gen_error(sxe, SX_ERR_XML_PARSE, "stream read error", "Maximum stanza size exceeded");
        _sx_event(s, event_ERROR, (void *) &sxe);

        _sx_error(s, stream_err_POLICY_VIOLATION, errstring);
        _sx_close(s);

        _sx_buffer_free(buf);

        return;
    }

    /* count bytes processed */
    s->tbytes += buf->len;

    /* done with the buffer */
    _sx_buffer_free(buf);

    /* process completed nads */
    if(s->state >= state_STREAM)
        while((nad = jqueue_pull(s->rnadq)) != NULL) {
            int plugin_error;
#ifdef SX_DEBUG
            const char *out; int len;
            nad_print(nad, 0, &out, &len);
            _sx_debug(ZONE, "completed nad: %.*s", len, out);
#endif

            /* check for errors */
            if(NAD_ENS(nad, 0) >= 0 && NAD_NURI_L(nad, NAD_ENS(nad, 0)) == strlen(uri_STREAMS) && strncmp(NAD_NURI(nad, NAD_ENS(nad, 0)), uri_STREAMS, strlen(uri_STREAMS)) == 0 && NAD_ENAME_L(nad, 0) == 5 && strncmp(NAD_ENAME(nad, 0), "error", 5) == 0) {

                errstring = NULL;

                /* get text error description if available - XMPP 4.7.2 */
                if((ns = nad_find_scoped_namespace(nad, uri_STREAM_ERR, NULL)) >= 0)
                    if((elem = nad_find_elem(nad, 0, ns, "text", 1)) >= 0)
                        if(NAD_CDATA_L(nad, elem) > 0) {
                            errstring = (char *) malloc(sizeof(char) * (NAD_CDATA_L(nad, elem) + 1));
                            sprintf(errstring, "%.*s", NAD_CDATA_L(nad, elem), NAD_CDATA(nad, elem));
                        }

                /* if not available, look for legacy error text as in <stream:error>description</stream:error> */
                if (errstring == NULL && NAD_CDATA_L(nad, 0) > 0) {
                    errstring = (char *) malloc(sizeof(char) * (NAD_CDATA_L(nad, 0) + 1));
                    sprintf(errstring, "%.*s", NAD_CDATA_L(nad, 0), NAD_CDATA(nad, 0));
                }

                /* if not available, log the whole packet for debugging */
                if (errstring == NULL) {
                    const char *xml;
                    int xlen;

                    nad_print(nad, 0, &xml, &xlen);
                    errstring = (char *) malloc(sizeof(char) * (xlen + 1));
                    sprintf(errstring, "%.*s", xlen, xml);
                }

                if(s->state < state_CLOSING) {
                    _sx_gen_error(sxe, SX_ERR_STREAM, "Stream error", errstring);
                    _sx_event(s, event_ERROR, (void *) &sxe);
                    _sx_state(s, state_CLOSING);
                }

                free(errstring);

                nad_free(nad);

                break;
            }

            /* check for close */
            if ((s->flags & SX_WEBSOCKET_WRAPPER) && NAD_ENS(nad, 0) >= 0 && NAD_NURI_L(nad, NAD_ENS(nad, 0)) == strlen(uri_XFRAMING) && strncmp(NAD_NURI(nad, NAD_ENS(nad, 0)), uri_XFRAMING, strlen(uri_XFRAMING)) == 0 && NAD_ENAME_L(nad, 0) == 5 && strncmp(NAD_ENAME(nad, 0), "close", 5) == 0) {
                _sx_debug(ZONE, "<close/> frame @ depth %d", s->depth);
                s->fail = 1;
                break;
            }

            /* run it by the plugins */
            if(_sx_chain_nad_read(s, nad) == 0)
                return;

            /* now let the plugins process the completed nad */
            plugin_error = 0;
            if(s->env != NULL)
                for(i = 0; i < s->env->nplugins; i++)
                    if(s->env->plugins[i]->process != NULL) {
                        int plugin_ret;
                        plugin_ret = (s->env->plugins[i]->process)(s, s->env->plugins[i], nad);
                        if(plugin_ret == 0) {
                            plugin_error ++;
                            break;
                        }
                    }

            /* hand it to the app */
            if ((plugin_error == 0) && (s->state < state_CLOSING))
                _sx_event(s, event_PACKET, (void *) nad);
        }

    /* something went wrong, bail */
    if(s->fail) {
        _sx_close(s);

        return;
    }

    /* stream was closed */
    if(s->depth < 0 && s->state < state_CLOSING) {
        /* close the stream if necessary */

        if(s->state >= state_STREAM_SENT) {
            if (s->flags & SX_WEBSOCKET_WRAPPER)
                jqueue_push(s->wbufq, _sx_buffer_new("<close xmlns='" uri_XFRAMING "' />", sizeof(uri_XFRAMING) + 17, NULL, NULL), 0);
            else
                jqueue_push(s->wbufq, _sx_buffer_new("</stream:stream>", 16, NULL, NULL), 0);
            s->want_write = 1;
        }

        _sx_state(s, state_CLOSING);

        return;
    }
}
Beispiel #9
0
static int _sx_compress_process(sx_t s, sx_plugin_t p, nad_t nad) {
    int flags;
    char *ns = NULL, *to = NULL, *from = NULL, *version = NULL;
    sx_error_t sxe;

    /* not interested if we're a server and we never offered it */
    if(s->type == type_SERVER && !(s->flags & SX_COMPRESS_OFFER))
        return 1;

    /* only want compress packets */
    if(NAD_ENS(nad, 0) < 0 || NAD_NURI_L(nad, NAD_ENS(nad, 0)) != sizeof(uri_COMPRESS)-1 || strncmp(NAD_NURI(nad, NAD_ENS(nad, 0)), uri_COMPRESS, sizeof(uri_COMPRESS)-1) != 0)
        return 1;

    /* compress from client */
    if(s->type == type_SERVER) {
        if(NAD_ENAME_L(nad, 0) == 8 && strncmp(NAD_ENAME(nad, 0), "compress", 8) == 0) {
            nad_free(nad);

            /* can't go on if we've been here before */
            if(s->compressed) {
                _sx_debug(ZONE, "compress requested on already compressed channel, dropping packet");
                return 0;
            }

            _sx_debug(ZONE, "compress requested, setting up");

            /* go ahead */
            jqueue_push(s->wbufq, _sx_buffer_new("<compressed xmlns='" uri_COMPRESS "'/>", sizeof(uri_COMPRESS)-1 + 22, _sx_compress_notify_compress, NULL), 0);
            s->want_write = 1;

            /* handled the packet */
            return 0;
        }
    }

    else if(s->type == type_CLIENT) {
        /* kick off the handshake */
        if(NAD_ENAME_L(nad, 0) == 7 && strncmp(NAD_ENAME(nad, 0), "compressed", 7) == 0) {
            nad_free(nad);

            /* save interesting bits */
            flags = s->flags;

            if(s->ns != NULL) ns = strdup(s->ns);

            if(s->req_to != NULL) to = strdup(s->req_to);
            if(s->req_from != NULL) from = strdup(s->req_from);
            if(s->req_version != NULL) version = strdup(s->req_version);

            /* reset state */
            _sx_reset(s);

            _sx_debug(ZONE, "server ready for compression, starting");

            /* second time round */
            sx_client_init(s, flags | SX_COMPRESS_WRAPPER, ns, to, from, version);

            /* free bits */
            if(ns != NULL) free(ns);
            if(to != NULL) free(to);
            if(from != NULL) free(from);
            if(version != NULL) free(version);

            return 0;
        }

        /* busted server */
        if(NAD_ENAME_L(nad, 0) == 7 && strncmp(NAD_ENAME(nad, 0), "failure", 7) == 0) {
            nad_free(nad);

            _sx_debug(ZONE, "server can't handle compression, business as usual");

            _sx_gen_error(sxe, SX_ERR_COMPRESS_FAILURE, "compress failure", "Server was unable to establish compression");
            _sx_event(s, event_ERROR, (void *) &sxe);

            return 0;
        }
    }

    _sx_debug(ZONE, "unknown compress namespace element '%.*s', dropping packet", NAD_ENAME_L(nad, 0), NAD_ENAME(nad, 0));
    nad_free(nad);
    return 0;
}