#include "system.h"
#include "conf.h"
#include "control.h"
+#include "control_common.h"
+#include "graph.h"
#include "logger.h"
#include "xalloc.h"
static int control_socket = -1;
static struct event control_event;
static splay_tree_t *control_socket_tree;
-extern char *controlfilename;
+extern char *controlsocketname;
-static void handle_control_data(int fd, short events, void *event) {
- char buf[MAXBUFSIZE];
- size_t inlen;
+static void handle_control_data(struct bufferevent *event, void *data) {
+ tinc_ctl_request_t req;
+ tinc_ctl_request_t res;
+ struct evbuffer *res_data = NULL;
+ void *req_data;
- inlen = read(fd, buf, sizeof buf);
+ if(EVBUFFER_LENGTH(event->input) < sizeof req)
+ return;
+
+ /* Copy the structure to ensure alignment */
+ memcpy(&req, EVBUFFER_DATA(event->input), sizeof req);
+
+ if(EVBUFFER_LENGTH(event->input) < req.length)
+ return;
+ req_data = EVBUFFER_DATA(event->input) + sizeof req;
+
+ if(req.length < sizeof req)
+ goto failure;
+
+ memset(&res, 0, sizeof res);
+ res.type = req.type;
+ res.id = req.id;
+
+ res_data = evbuffer_new();
+ if(res_data == NULL) {
+ res.res_errno = ENOMEM;
+ goto respond;
+ }
+
+ if(req.type == REQ_STOP) {
+ logger(LOG_NOTICE, _("Got '%s' command"), "stop");
+ event_loopexit(NULL);
+ goto respond;
+ }
+
+ if(req.type == REQ_DUMP_NODES) {
+ logger(LOG_NOTICE, _("Got '%s' command"), "dump nodes");
+ res.res_errno = dump_nodes(res_data);
+ goto respond;
+ }
+
+ if(req.type == REQ_DUMP_EDGES) {
+ logger(LOG_NOTICE, _("Got '%s' command"), "dump edges");
+ res.res_errno = dump_edges(res_data);
+ goto respond;
+ }
+
+ if(req.type == REQ_DUMP_SUBNETS) {
+ logger(LOG_NOTICE, _("Got '%s' command"), "dump subnets");
+ res.res_errno = dump_subnets(res_data);
+ goto respond;
+ }
- if(inlen <= 0) {
- logger(LOG_DEBUG, _("Closing control socket"));
- event_del(event);
- splay_delete(control_socket_tree, event);
- close(fd);
+ if(req.type == REQ_DUMP_CONNECTIONS) {
+ logger(LOG_NOTICE, _("Got '%s' command"), "dump connections");
+ res.res_errno = dump_connections(res_data);
+ goto respond;
}
+
+ if(req.type == REQ_DUMP_GRAPH) {
+ logger(LOG_NOTICE, _("Got '%s' command"), "dump graph");
+ res.res_errno = dump_graph(res_data);
+ goto respond;
+ }
+
+ if(req.type == REQ_PURGE) {
+ logger(LOG_NOTICE, _("Got '%s' command"), "purge");
+ purge();
+ goto respond;
+ }
+
+ if(req.type == REQ_SET_DEBUG) {
+ debug_t new_debug_level;
+
+ logger(LOG_NOTICE, _("Got '%s' command"), "debug");
+ if(req.length != sizeof req + sizeof debug_level)
+ res.res_errno = EINVAL;
+ else {
+ memcpy(&new_debug_level, req_data, sizeof new_debug_level);
+ logger(LOG_NOTICE, _("Changing debug level from %d to %d"),
+ debug_level, new_debug_level);
+ if(evbuffer_add_printf(res_data,
+ _("Changing debug level from %d to %d\n"),
+ debug_level, new_debug_level) == -1)
+ res.res_errno = errno;
+ debug_level = new_debug_level;
+ }
+ goto respond;
+ }
+
+ if(req.type == REQ_RETRY) {
+ logger(LOG_NOTICE, _("Got '%s' command"), "retry");
+ retry();
+ goto respond;
+ }
+
+ if(req.type == REQ_RELOAD) {
+ logger(LOG_NOTICE, _("Got '%s' command"), "reload");
+ res.res_errno = reload_configuration();
+ goto respond;
+ }
+
+ logger(LOG_DEBUG, _("Malformed control command received"));
+ res.res_errno = EINVAL;
+
+respond:
+ res.length = (sizeof res)
+ + ((res_data == NULL) ? 0 : EVBUFFER_LENGTH(res_data));
+ evbuffer_drain(event->input, req.length);
+ if(bufferevent_write(event, &res, sizeof res) == -1)
+ goto failure;
+ if(res_data != NULL) {
+ if(bufferevent_write_buffer(event, res_data) == -1)
+ goto failure;
+ evbuffer_free(res_data);
+ }
+ return;
+
+failure:
+ logger(LOG_INFO, _("Closing control socket on error"));
+ evbuffer_free(res_data);
+ close(event->ev_read.ev_fd);
+ splay_delete(control_socket_tree, event);
+}
+
+static void handle_control_error(struct bufferevent *event, short what, void *data) {
+ if(what & EVBUFFER_EOF)
+ logger(LOG_DEBUG, _("Control socket connection closed by peer"));
+ else
+ logger(LOG_DEBUG, _("Error while reading from control socket: %s"), strerror(errno));
+
+ close(event->ev_read.ev_fd);
+ splay_delete(control_socket_tree, event);
}
static void handle_new_control_socket(int fd, short events, void *data) {
int newfd;
- struct event *ev;
+ struct bufferevent *ev;
+ tinc_ctl_greeting_t greeting;
newfd = accept(fd, NULL, NULL);
return;
}
- ev = xmalloc(sizeof *ev);
- event_set(ev, newfd, EV_READ | EV_PERSIST, handle_control_data, ev);
- event_add(ev, NULL);
+ ev = bufferevent_new(newfd, handle_control_data, NULL, handle_control_error, NULL);
+ if(!ev) {
+ logger(LOG_ERR, _("Could not create bufferevent for new control connection: %s"), strerror(errno));
+ close(newfd);
+ return;
+ }
+
+ memset(&greeting, 0, sizeof greeting);
+ greeting.version = TINC_CTL_VERSION_CURRENT;
+ greeting.pid = getpid();
+ if(bufferevent_write(ev, &greeting, sizeof greeting) == -1) {
+ logger(LOG_ERR,
+ _("Cannot send greeting for new control connection: %s"),
+ strerror(errno));
+ bufferevent_free(ev);
+ close(newfd);
+ return;
+ }
+
+ bufferevent_enable(ev, EV_READ);
splay_insert(control_socket_tree, ev);
logger(LOG_DEBUG, _("Control socket connection accepted"));
return a < b ? -1 : a > b ? 1 : 0;
}
-void init_control() {
+bool init_control() {
+ int result;
struct sockaddr_un addr;
+ char *lastslash;
- control_socket_tree = splay_alloc_tree((splay_compare_t)control_compare, (splay_action_t)free);
-
- if(strlen(controlfilename) >= sizeof addr.sun_path) {
+ if(strlen(controlsocketname) >= sizeof addr.sun_path) {
logger(LOG_ERR, _("Control socket filename too long!"));
- return;
+ goto bail;
}
memset(&addr, 0, sizeof addr);
addr.sun_family = AF_UNIX;
- strncpy(addr.sun_path, controlfilename, sizeof addr.sun_path - 1);
+ strncpy(addr.sun_path, controlsocketname, sizeof addr.sun_path - 1);
control_socket = socket(PF_UNIX, SOCK_STREAM, 0);
if(control_socket < 0) {
logger(LOG_ERR, _("Creating UNIX socket failed: %s"), strerror(errno));
- return;
+ goto bail;
}
- unlink(controlfilename);
- if(bind(control_socket, (struct sockaddr *)&addr, sizeof addr) < 0) {
- logger(LOG_ERR, _("Can't bind to %s: %s\n"), controlfilename, strerror(errno));
- close(control_socket);
- return;
+ /*
+ * Restrict connections to our control socket by ensuring the parent
+ * directory can be traversed only by root. Note this is not totally
+ * race-free unless all ancestors are writable only by trusted users,
+ * which we don't verify.
+ */
+
+ struct stat statbuf;
+ lastslash = strrchr(controlsocketname, '/');
+ if(lastslash != NULL) {
+ *lastslash = 0; /* temporarily change controlsocketname to be dir */
+ if(mkdir(controlsocketname, 0700) < 0 && errno != EEXIST) {
+ logger(LOG_ERR, _("Unable to create control socket directory %s: %s"), controlsocketname, strerror(errno));
+ *lastslash = '/';
+ goto bail;
+ }
+
+ result = stat(controlsocketname, &statbuf);
+ *lastslash = '/';
+ } else
+ result = stat(".", &statbuf);
+
+ if(result < 0) {
+ logger(LOG_ERR, _("Examining control socket directory failed: %s"), strerror(errno));
+ goto bail;
+ }
+
+ if(statbuf.st_uid != 0 || (statbuf.st_mode & S_IXOTH) != 0 || (statbuf.st_gid != 0 && (statbuf.st_mode & S_IXGRP)) != 0) {
+ logger(LOG_ERR, _("Control socket directory ownership/permissions insecure."));
+ goto bail;
+ }
+
+ result = bind(control_socket, (struct sockaddr *)&addr, sizeof addr);
+
+ if(result < 0 && errno == EADDRINUSE) {
+ result = connect(control_socket, (struct sockaddr *)&addr, sizeof addr);
+ if(result < 0) {
+ logger(LOG_WARNING, _("Removing old control socket."));
+ unlink(controlsocketname);
+ result = bind(control_socket, (struct sockaddr *)&addr, sizeof addr);
+ } else {
+ if(netname)
+ logger(LOG_ERR, _("Another tincd is already running for net `%s'."), netname);
+ else
+ logger(LOG_ERR, _("Another tincd is already running."));
+ goto bail;
+ }
+ }
+
+ if(result < 0) {
+ logger(LOG_ERR, _("Can't bind to %s: %s"), controlsocketname, strerror(errno));
+ goto bail;
}
if(listen(control_socket, 3) < 0) {
- logger(LOG_ERR, _("Can't listen on %s: %s\n"), controlfilename, strerror(errno));
- close(control_socket);
- return;
+ logger(LOG_ERR, _("Can't listen on %s: %s"), controlsocketname, strerror(errno));
+ goto bail;
}
+ control_socket_tree = splay_alloc_tree((splay_compare_t)control_compare, (splay_action_t)bufferevent_free);
+
event_set(&control_event, control_socket, EV_READ | EV_PERSIST, handle_new_control_socket, NULL);
event_add(&control_event, NULL);
-}
+ return true;
-void exit_control() {
- if(control_socket >= 0) {
- event_del(&control_event);
+bail:
+ if(control_socket != -1) {
close(control_socket);
+ control_socket = -1;
}
+ return false;
+}
+
+void exit_control() {
+ event_del(&control_event);
+ close(control_socket);
+ unlink(controlsocketname);
}