/***
This file is part of systemd.
Copyright 2013 Daniel Mack
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see .
***/
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include "kdbus.h"
#include "sd-bus.h"
#include "bus-internal.h"
#include "sd-daemon.h"
#include "sd-event.h"
#include "event-util.h"
#include "bus-util.h"
#include "bus-error.h"
#include "bus-message.h"
#include "bus-kernel.h"
#include "socket-util.h"
#include "util.h"
#include "build.h"
#include "strv.h"
#include "sd-id128.h"
#include "async.h"
#include "hashmap.h"
#include "def.h"
#include "unit-name.h"
#include "bus-control.h"
#define CLIENTS_MAX 1024
#define MATCHES_MAX 1024
typedef struct Match Match;
typedef struct Client Client;
typedef struct Context Context;
struct Match {
Client *client;
char *match;
uint64_t cookie;
LIST_FIELDS(Match, matches);
};
struct Client {
Context *context;
uint64_t id;
uint64_t next_cookie;
Hashmap *matches;
unsigned n_matches;
char *watch;
};
struct Context {
sd_bus *bus;
sd_event *event;
Hashmap *clients;
};
static void match_free(Match *m) {
if (!m)
return;
if (m->client) {
Match *first;
first = hashmap_get(m->client->matches, m->match);
LIST_REMOVE(matches, first, m);
if (first)
assert_se(hashmap_replace(m->client->matches, m->match, first) >= 0);
else
hashmap_remove(m->client->matches, m->match);
m->client->n_matches--;
}
free(m->match);
free(m);
}
static int match_new(Client *c, struct bus_match_component *components, unsigned n_components, Match **_m) {
Match *m, *first;
int r;
assert(c);
assert(_m);
r = hashmap_ensure_allocated(&c->matches, string_hash_func, string_compare_func);
if (r < 0)
return r;
m = new0(Match, 1);
if (!m)
return -ENOMEM;
m->match = bus_match_to_string(components, n_components);
if (!m->match) {
r = -ENOMEM;
goto fail;
}
m->cookie = ++c->next_cookie;
first = hashmap_get(c->matches, m->match);
LIST_PREPEND(matches, first, m);
r = hashmap_replace(c->matches, m->match, first);
if (r < 0) {
LIST_REMOVE(matches, first, m);
goto fail;
}
m->client = c;
c->n_matches++;
*_m = m;
m = NULL;
return 0;
fail:
match_free(m);
return r;
}
static int on_name_owner_changed(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error);
static void client_free(Client *c) {
Match *m;
if (!c)
return;
if (c->context) {
if (c->watch)
sd_bus_remove_match(c->context->bus, c->watch, on_name_owner_changed, c);
assert_se(hashmap_remove(c->context->clients, &c->id) == c);
}
while ((m = hashmap_first(c->matches)))
match_free(m);
hashmap_free(c->matches);
free(c->watch);
free(c);
}
static int on_name_owner_changed(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
Client *c = userdata;
assert(bus);
assert(m);
client_free(c);
return 0;
}
static int client_acquire(Context *context, uint64_t id, Client **_c) {
char *watch = NULL;
Client *c;
int r;
assert(context);
assert(_c);
c = hashmap_get(context->clients, &id);
if (c) {
*_c = c;
return 0;
}
if (hashmap_size(context->clients) >= CLIENTS_MAX)
return -ENOBUFS;
r = hashmap_ensure_allocated(&context->clients, uint64_hash_func, uint64_compare_func);
if (r < 0)
return r;
c = new0(Client, 1);
if (!c)
return -ENOMEM;
c->id = id;
r = hashmap_put(context->clients, &c->id, c);
if (r < 0)
goto fail;
c->context = context;
if (asprintf(&watch,
"type='signal',"
"sender='org.freedesktop.DBus',"
"path='/org/freedesktop/DBus',"
"interface='org.freedesktop.DBus',"
"member='NameOwnerChanged',"
"arg0=':1.%llu'", (unsigned long long) id) < 0) {
r = -ENOMEM;
goto fail;
}
r = sd_bus_add_match(context->bus, watch, on_name_owner_changed, c);
if (r < 0) {
free(watch);
goto fail;
}
c->watch = watch;
*_c = c;
return 0;
fail:
client_free(c);
return r;
}
static int driver_add_match(sd_bus *bus, sd_bus_message *message, void *userdata, sd_bus_error *error) {
struct bus_match_component *components = NULL;
Context *context = userdata;
unsigned n_components = 0;
Match *m = NULL;
Client *c = NULL;
char *arg0;
uint64_t id;
int r;
assert(bus);
assert(message);
assert(context);
r = sd_bus_message_read(message, "s", &arg0);
if (r < 0)
return r;
r = bus_kernel_parse_unique_name(message->sender, &id);
if (r < 0)
return r;
r = client_acquire(context, id, &c);
if (r == -ENOBUFS)
return sd_bus_error_setf(error, SD_BUS_ERROR_LIMITS_EXCEEDED, "Reached limit of %u clients", CLIENTS_MAX);
if (r < 0)
return r;
if (c->n_matches >= MATCHES_MAX) {
r = sd_bus_error_setf(error, SD_BUS_ERROR_LIMITS_EXCEEDED, "Reached limit of %u matches per client", MATCHES_MAX);
goto fail;
}
r = bus_match_parse(arg0, &components, &n_components);
if (r < 0) {
r = sd_bus_error_setf(error, SD_BUS_ERROR_MATCH_RULE_INVALID, "Match rule \"%s\" is not valid", arg0);
goto fail;
}
r = match_new(c, components, n_components, &m);
if (r < 0)
goto fail;
r = bus_add_match_internal_kernel(bus, id, components, n_components, m->cookie);
if (r < 0)
goto fail;
bus_match_parse_free(components, n_components);
return sd_bus_reply_method_return(message, NULL);
fail:
bus_match_parse_free(components, n_components);
match_free(m);
if (c->n_matches <= 0)
client_free(c);
return r;
}
static int driver_remove_match(sd_bus *bus, sd_bus_message *message, void *userdata, sd_bus_error *error) {
struct bus_match_component *components = NULL;
_cleanup_free_ char *normalized = NULL;
Context *context = userdata;
unsigned n_components = 0;
Client *c = NULL;
Match *m = NULL;
char *arg0;
uint64_t id;
int r;
assert(bus);
assert(message);
assert(context);
r = sd_bus_message_read(message, "s", &arg0);
if (r < 0)
return r;
r = bus_kernel_parse_unique_name(message->sender, &id);
if (r < 0)
return r;
c = hashmap_get(context->clients, &id);
if (!c)
return sd_bus_error_setf(error, SD_BUS_ERROR_MATCH_RULE_NOT_FOUND, "You have not registered any matches.");
r = bus_match_parse(arg0, &components, &n_components);
if (r < 0) {
r = sd_bus_error_setf(error, SD_BUS_ERROR_MATCH_RULE_INVALID, "Match rule \"%s\" is not valid", arg0);
goto finish;
}
normalized = bus_match_to_string(components, n_components);
if (!normalized) {
r = -ENOMEM;
goto finish;
}
m = hashmap_get(c->matches, normalized);
if (!m) {
r = sd_bus_error_setf(error, SD_BUS_ERROR_MATCH_RULE_NOT_FOUND, "Match rule \"%s\" not found.");
goto finish;
}
bus_remove_match_internal_kernel(bus, id, m->cookie);
match_free(m);
r = sd_bus_reply_method_return(message, NULL);
finish:
bus_match_parse_free(components, n_components);
if (c->n_matches <= 0)
client_free(c);
return r;
}
static int get_creds(sd_bus *bus, sd_bus_message *m, uint64_t mask, sd_bus_creds **_creds, sd_bus_error *error) {
_cleanup_bus_creds_unref_ sd_bus_creds *c = NULL;
const char *name;
int r;
assert(bus);
assert(m);
assert(_creds);
r = sd_bus_message_read(m, "s", &name);
if (r < 0)
return r;
assert_return(service_name_is_valid(name), -EINVAL);
r = sd_bus_get_owner(bus, name, mask, &c);
if (r == -ENOENT || r == -ENXIO)
return sd_bus_error_setf(error, SD_BUS_ERROR_NAME_HAS_NO_OWNER, "Name %s is currently not owned by anyone.", name);
if (r < 0)
return r;
if ((c->mask & mask) != mask)
return -ENOTSUP;
*_creds = c;
c = NULL;
return 0;
}
static int driver_get_security_context(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
_cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
_cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL;
int r;
r = get_creds(bus, m, SD_BUS_CREDS_SELINUX_CONTEXT, &creds, error);
if (r < 0)
return r;
r = sd_bus_message_new_method_return(m, &reply);
if (r < 0)
return r;
r = sd_bus_message_append_array(reply, 'y', creds->label, strlen(creds->label));
if (r < 0)
return r;
return sd_bus_send(bus, reply, NULL);
}
static int driver_get_pid(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
_cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL;
int r;
r = get_creds(bus, m, SD_BUS_CREDS_PID, &creds, error);
if (r < 0)
return r;
return sd_bus_reply_method_return(m, "u", (uint32_t) creds->pid);
}
static int driver_get_user(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
_cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL;
int r;
r = get_creds(bus, m, SD_BUS_CREDS_UID, &creds, error);
if (r < 0)
return r;
return sd_bus_reply_method_return(m, "u", (uint32_t) creds->uid);
}
static int driver_get_name_owner(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
_cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL;
int r;
r = get_creds(bus, m, SD_BUS_CREDS_UNIQUE_NAME, &creds, error);
if (r < 0)
return r;
return sd_bus_reply_method_return(m, "s", creds->unique_name);
}
static int driver_get_id(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
sd_id128_t server_id;
char buf[SD_ID128_STRING_MAX];
int r;
r = sd_bus_get_server_id(bus, &server_id);
if (r < 0)
return r;
return sd_bus_reply_method_return(m, "s", sd_id128_to_string(server_id, buf));
}
static int driver_hello(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
return sd_bus_reply_method_return(m, "s", m->sender);
}
static int return_strv(sd_bus *bus, sd_bus_message *m, char **l) {
_cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
int r;
r = sd_bus_message_new_method_return(m, &reply);
if (r < 0)
return r;
r = sd_bus_message_append_strv(reply, l);
if (r < 0)
return r;
return sd_bus_send(bus, reply, NULL);
}
static int driver_list_names(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
_cleanup_strv_free_ char **names = NULL;
int r;
r = sd_bus_list_names(bus, &names, NULL);
if (r < 0)
return r;
/* Let's sort the names list to make it stable */
strv_sort(names);
return return_strv(bus, m, names);
}
static int driver_list_activatable_names(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
_cleanup_strv_free_ char **names = NULL;
int r;
r = sd_bus_list_names(bus, NULL, &names);
if (r < 0)
return r;
/* Let's sort the names list to make it stable */
strv_sort(names);
return return_strv(bus, m, names);
}
static int driver_list_queued_owners(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
struct kdbus_cmd_name_list cmd = {};
struct kdbus_name_list *name_list;
struct kdbus_cmd_name *name;
_cleanup_strv_free_ char **owners = NULL;
char *arg0;
int r;
r = sd_bus_message_read(m, "s", &arg0);
if (r < 0)
return r;
assert_return(service_name_is_valid(arg0), -EINVAL);
cmd.flags = KDBUS_NAME_LIST_QUEUED;
r = ioctl(bus->input_fd, KDBUS_CMD_NAME_LIST, &cmd);
if (r < 0)
return -errno;
name_list = (struct kdbus_name_list *) ((uint8_t *) bus->kdbus_buffer + cmd.offset);
KDBUS_ITEM_FOREACH(name, name_list, names) {
char *n;
if (name->size <= sizeof(*name))
continue;
if (!streq(name->name, arg0))
continue;
if (asprintf(&n, ":1.%llu", (unsigned long long) name->owner_id) < 0)
return -ENOMEM;
r = strv_push(&owners, n);
if (r < 0) {
free(n);
return -ENOMEM;
}
}
r = ioctl(bus->input_fd, KDBUS_CMD_FREE, &cmd.offset);
if (r < 0)
return -errno;
return return_strv(bus, m, owners);
}
static int driver_name_has_owner(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
const char *name;
int r;
r = sd_bus_message_read(m, "s", &name);
if (r < 0)
return r;
assert_return(service_name_is_valid(name), -EINVAL);
r = sd_bus_get_owner(bus, name, 0, NULL);
if (r < 0 && r != -ENOENT && r != -ENXIO)
return r;
return sd_bus_reply_method_return(m, "b", r >= 0);
}
static int driver_request_name(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
struct kdbus_cmd_name *n;
uint32_t flags;
size_t size, l;
uint64_t id;
const char *name;
int r;
r = sd_bus_message_read(m, "su", &name, &flags);
if (r < 0)
return r;
assert_return(service_name_is_valid(name), -EINVAL);
assert_return((flags & ~(BUS_NAME_ALLOW_REPLACEMENT|BUS_NAME_REPLACE_EXISTING|BUS_NAME_DO_NOT_QUEUE)) == 0, -EINVAL);
l = strlen(name);
size = offsetof(struct kdbus_cmd_name, name) + l + 1;
n = alloca0(size);
n->size = size;
memcpy(n->name, name, l+1);
kdbus_translate_request_name_flags(flags, (uint64_t *) &n->flags);
/* This function is open-coded because we request the name 'on behalf'
* of the requesting connection */
r = bus_kernel_parse_unique_name(m->sender, &id);
if (r < 0)
return r;
n->owner_id = id;
r = ioctl(bus->input_fd, KDBUS_CMD_NAME_ACQUIRE, n);
if (r < 0) {
if (errno == EEXIST)
return sd_bus_reply_method_return(m, "u", BUS_NAME_EXISTS);
if (errno == EALREADY)
return sd_bus_reply_method_return(m, "u", BUS_NAME_ALREADY_OWNER);
return -errno;
}
if (n->flags & KDBUS_NAME_IN_QUEUE)
return sd_bus_reply_method_return(m, "u", BUS_NAME_IN_QUEUE);
return sd_bus_reply_method_return(m, "u", BUS_NAME_PRIMARY_OWNER);
}
static int driver_release_name(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
struct kdbus_cmd_name *n;
const char *name;
size_t l, size;
uint64_t id;
int r;
r = sd_bus_message_read(m, "s", &name);
if (r < 0)
return r;
assert_return(service_name_is_valid(name), -EINVAL);
l = strlen(name);
size = offsetof(struct kdbus_cmd_name, name) + l + 1;
n = alloca0(size);
n->size = size;
memcpy(n->name, name, l+1);
/* This function is open-coded because we request the name 'on behalf'
* of the requesting connection */
r = bus_kernel_parse_unique_name(m->sender, &id);
if (r < 0)
return r;
n->owner_id = id;
r = ioctl(bus->input_fd, KDBUS_CMD_NAME_RELEASE, n);
if (r < 0) {
if (errno == ESRCH)
return sd_bus_reply_method_return(m, "u", BUS_NAME_NON_EXISTENT);
if (errno == EADDRINUSE)
return sd_bus_reply_method_return(m, "u", BUS_NAME_NOT_OWNER);
return -errno;
}
return sd_bus_reply_method_return(m, "u", BUS_NAME_RELEASED);
}
static int driver_start_service_by_name(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
_cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
_cleanup_strv_free_ char **t = NULL;
_cleanup_free_ char *path = NULL;
uint32_t flags;
char *name, *u;
int r;
r = sd_bus_message_read(m, "su", &name, &flags);
if (r < 0)
return r;
assert_return(service_name_is_valid(name), -EINVAL);
assert_return(flags == 0, -ENOTSUP);
r = sd_bus_get_owner(bus, name, 0, NULL);
if (r >= 0)
return sd_bus_reply_method_return(m, "u", BUS_START_REPLY_ALREADY_RUNNING);
if (r != -ENOENT)
return r;
u = strappenda(name, ".busname");
path = unit_dbus_path_from_name(u);
if (!path)
return -ENOMEM;
r = sd_bus_get_property_strv(
bus,
"org.freedesktop.systemd1",
path,
"org.freedesktop.systemd1.Unit",
"Triggers",
error,
&t);
if (r < 0)
return r;
if (!t || !t[0] || t[1])
return -EIO;
r = sd_bus_call_method(
bus,
"org.freedesktop.systemd1",
"/org/freedesktop/systemd1",
"org.freedesktop.systemd1.Manager",
"StartUnit",
error,
&reply,
"ss",
t[0],
"replace");
if (r < 0)
return r;
return sd_bus_reply_method_return(m, "u", BUS_START_REPLY_SUCCESS);
}
static int driver_unsupported(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
return sd_bus_error_setf(error, SD_BUS_ERROR_NOT_SUPPORTED, "%s() is not supported", sd_bus_message_get_member(m));
}
static const sd_bus_vtable driver_vtable[] = {
SD_BUS_VTABLE_START(0),
SD_BUS_METHOD("AddMatch", "s", NULL, driver_add_match, SD_BUS_VTABLE_UNPRIVILEGED),
SD_BUS_METHOD("GetConnectionSELinuxSecurityContext", "s", "ay", driver_get_security_context, SD_BUS_VTABLE_UNPRIVILEGED),
SD_BUS_METHOD("GetConnectionUnixProcessID", "s", "u", driver_get_pid, SD_BUS_VTABLE_UNPRIVILEGED),
SD_BUS_METHOD("GetConnectionUnixUser", "s", "u", driver_get_user, SD_BUS_VTABLE_UNPRIVILEGED),
SD_BUS_METHOD("GetId", NULL, "s", driver_get_id, SD_BUS_VTABLE_UNPRIVILEGED),
SD_BUS_METHOD("GetNameOwner", "s", "s", driver_get_name_owner, SD_BUS_VTABLE_UNPRIVILEGED),
SD_BUS_METHOD("Hello", NULL, "s", driver_hello, SD_BUS_VTABLE_UNPRIVILEGED),
SD_BUS_METHOD("ListActivatableNames", NULL, "as", driver_list_activatable_names, SD_BUS_VTABLE_UNPRIVILEGED),
SD_BUS_METHOD("ListNames", NULL, "as", driver_list_names, SD_BUS_VTABLE_UNPRIVILEGED),
SD_BUS_METHOD("ListQueuedOwners", "s", "as", driver_list_queued_owners, SD_BUS_VTABLE_UNPRIVILEGED),
SD_BUS_METHOD("NameHasOwner", "s", "b", driver_name_has_owner, SD_BUS_VTABLE_UNPRIVILEGED),
SD_BUS_METHOD("ReleaseName", "s", "u", driver_release_name, SD_BUS_VTABLE_UNPRIVILEGED),
SD_BUS_METHOD("ReloadConfig", NULL, NULL, driver_unsupported, SD_BUS_VTABLE_DEPRECATED),
SD_BUS_METHOD("RemoveMatch", "s", NULL, driver_remove_match, SD_BUS_VTABLE_UNPRIVILEGED),
SD_BUS_METHOD("RequestName", "su", "u", driver_request_name, SD_BUS_VTABLE_UNPRIVILEGED),
SD_BUS_METHOD("StartServiceByName", "su", "u", driver_start_service_by_name, SD_BUS_VTABLE_UNPRIVILEGED),
SD_BUS_METHOD("UpdateActivationEnvironment", "a{ss}", NULL, driver_unsupported, SD_BUS_VTABLE_DEPRECATED),
SD_BUS_SIGNAL("NameAcquired", "s", SD_BUS_VTABLE_DEPRECATED),
SD_BUS_SIGNAL("NameLost", "s", SD_BUS_VTABLE_DEPRECATED),
SD_BUS_SIGNAL("NameOwnerChanged", "sss", 0),
SD_BUS_VTABLE_END
};
static int connect_bus(Context *c) {
int r;
assert(c);
r = sd_bus_default_system(&c->bus);
if (r < 0) {
log_error("Failed to create bus: %s", strerror(-r));
return r;
}
if (!c->bus->is_kernel) {
log_error("Not running on kdbus");
return -EPERM;
}
r = sd_bus_add_object_vtable(c->bus, "/org/freedesktop/DBus", "org.freedesktop.DBus", driver_vtable, c);
if (r < 0) {
log_error("Failed to add manager object vtable: %s", strerror(-r));
return r;
}
r = sd_bus_request_name(c->bus, "org.freedesktop.DBus", 0);
if (r < 0) {
log_error("Unable to request name: %s", strerror(-r));
return r;
}
r = sd_bus_attach_event(c->bus, c->event, 0);
if (r < 0) {
log_error("Error while adding bus to event loop: %s", strerror(-r));
return r;
}
return 0;
}
static bool check_idle(void *userdata) {
Context *c = userdata;
assert(c);
return hashmap_isempty(c->clients);
}
int main(int argc, char *argv[]) {
Context context = {};
Client *c;
int r;
log_set_target(LOG_TARGET_AUTO);
log_parse_environment();
log_open();
if (argc != 1) {
log_error("This program takes no arguments.");
r = -EINVAL;
goto finish;
}
r = sd_event_default(&context.event);
if (r < 0) {
log_error("Failed to allocate event loop: %s", strerror(-r));
goto finish;
}
sd_event_set_watchdog(context.event, true);
r = connect_bus(&context);
if (r < 0)
goto finish;
r = bus_event_loop_with_idle(context.event, context.bus, "org.freedesktop.DBus", DEFAULT_EXIT_USEC, check_idle, &context);
if (r < 0) {
log_error("Failed to run event loop: %s", strerror(-r));
goto finish;
}
finish:
while ((c = hashmap_first(context.clients)))
client_free(c);
sd_bus_unref(context.bus);
sd_event_unref(context.event);
return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
}