This file is part of systemd.
Copyright 2010 Lennart Poettering
+ Copyright 2013 Daniel Mack
+ Copyright 2014 Kay Sievers
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
#include "build.h"
#include "strv.h"
#include "def.h"
-
-static const char *arg_address = DEFAULT_SYSTEM_BUS_PATH;
+#include "capability.h"
+#include "bus-control.h"
+#include "smack-util.h"
+#include "set.h"
+#include "bus-xml-policy.h"
+#include "driver.h"
+#include "proxy.h"
+#include "synthesize.h"
+
+static char *arg_address = NULL;
static char *arg_command_line_buffer = NULL;
+static bool arg_drop_privileges = false;
+static char **arg_configuration = NULL;
static int help(void) {
printf("%s [OPTIONS...]\n\n"
"Connect STDIO or a socket to a given bus address.\n\n"
- " -h --help Show this help\n"
- " --version Show package version\n"
- " --address=ADDRESS Connect to the bus specified by ADDRESS\n"
- " (default: " DEFAULT_SYSTEM_BUS_PATH ")\n",
+ " -h --help Show this help\n"
+ " --version Show package version\n"
+ " --drop-privileges Drop privileges\n"
+ " --configuration=PATH Configuration file or directory\n"
+ " --machine=MACHINE Connect to specified machine\n"
+ " --address=ADDRESS Connect to the bus specified by ADDRESS\n"
+ " (default: " DEFAULT_SYSTEM_BUS_ADDRESS ")\n",
program_invocation_short_name);
return 0;
enum {
ARG_VERSION = 0x100,
ARG_ADDRESS,
+ ARG_DROP_PRIVILEGES,
+ ARG_CONFIGURATION,
+ ARG_MACHINE,
};
static const struct option options[] = {
- { "help", no_argument, NULL, 'h' },
- { "version", no_argument, NULL, ARG_VERSION },
- { "address", required_argument, NULL, ARG_ADDRESS },
- { NULL, 0, NULL, 0 }
+ { "help", no_argument, NULL, 'h' },
+ { "version", no_argument, NULL, ARG_VERSION },
+ { "address", required_argument, NULL, ARG_ADDRESS },
+ { "drop-privileges", no_argument, NULL, ARG_DROP_PRIVILEGES },
+ { "configuration", required_argument, NULL, ARG_CONFIGURATION },
+ { "machine", required_argument, NULL, ARG_MACHINE },
+ {},
};
- int c;
+ int c, r;
assert(argc >= 0);
assert(argv);
- while ((c = getopt_long(argc, argv, "h", options, NULL)) >= 0) {
+ while ((c = getopt_long(argc, argv, "h", options, NULL)) >= 0)
switch (c) {
puts(SYSTEMD_FEATURES);
return 0;
- case ARG_ADDRESS:
- arg_address = optarg;
+ case ARG_ADDRESS: {
+ char *a;
+
+ a = strdup(optarg);
+ if (!a)
+ return log_oom();
+
+ free(arg_address);
+ arg_address = a;
+ break;
+ }
+
+ case ARG_DROP_PRIVILEGES:
+ arg_drop_privileges = true;
+ break;
+
+ case ARG_CONFIGURATION:
+ r = strv_extend(&arg_configuration, optarg);
+ if (r < 0)
+ return log_oom();
break;
+ case ARG_MACHINE: {
+ _cleanup_free_ char *e = NULL;
+ char *a;
+
+ e = bus_address_escape(optarg);
+ if (!e)
+ return log_oom();
+
+#ifdef ENABLE_KDBUS
+ a = strjoin("x-machine-kernel:machine=", e, ";x-machine-unix:machine=", e, NULL);
+#else
+ a = strjoin("x-machine-unix:machine=", e, NULL);
+#endif
+ if (!a)
+ return log_oom();
+
+ free(arg_address);
+ arg_address = a;
+
+ break;
+ }
+
case '?':
return -EINVAL;
default:
assert_not_reached("Unhandled option");
}
- }
/* If the first command line argument is only "x" characters
* we'll write who we are talking to into it, so that "ps" is
* explanatory */
arg_command_line_buffer = argv[optind];
- if (argc > optind + 1 ||
- (arg_command_line_buffer && arg_command_line_buffer[strspn(arg_command_line_buffer, "x")] != 0)) {
+ if (argc > optind + 1 || (arg_command_line_buffer && !in_charset(arg_command_line_buffer, "x"))) {
log_error("Too many arguments");
return -EINVAL;
}
+ if (!arg_address) {
+ arg_address = strdup(DEFAULT_SYSTEM_BUS_ADDRESS);
+ if (!arg_address)
+ return log_oom();
+ }
+
return 1;
}
assert(a);
assert(b);
- r = sd_bus_get_peer_creds(b, SD_BUS_CREDS_UID|SD_BUS_CREDS_PID|SD_BUS_CREDS_CMDLINE|SD_BUS_CREDS_COMM, &creds);
+ r = sd_bus_get_owner_creds(b, SD_BUS_CREDS_UID|SD_BUS_CREDS_PID|SD_BUS_CREDS_CMDLINE|SD_BUS_CREDS_COMM|SD_BUS_CREDS_AUGMENT, &creds);
if (r < 0)
return r;
pid, p,
uid, name,
a->unique_name);
- ;
- return 0;
-}
-
-static int synthesize_name_acquired(sd_bus *a, sd_bus *b, sd_bus_message *m) {
- _cleanup_bus_message_unref_ sd_bus_message *n = NULL;
- const char *name, *old_owner, *new_owner;
- int r;
-
- assert(a);
- assert(b);
- assert(m);
-
- /* If we get NameOwnerChanged for our own name, we need to
- * synthesize NameLost/NameAcquired, since socket clients need
- * that, even though it is obsoleted on kdbus */
-
- if (!a->is_kernel)
- return 0;
-
- if (!sd_bus_message_is_signal(m, "org.freedesktop.DBus", "NameOwnerChanged") ||
- !streq_ptr(m->path, "/org/freedesktop/DBus") ||
- !streq_ptr(m->sender, "org.freedesktop.DBus"))
- return 0;
-
- r = sd_bus_message_read(m, "sss", &name, &old_owner, &new_owner);
- if (r < 0)
- return r;
-
- r = sd_bus_message_rewind(m, true);
- if (r < 0)
- return r;
-
- if (streq(old_owner, a->unique_name)) {
-
- r = sd_bus_message_new_signal(
- b,
- &n,
- "/org/freedesktop/DBus",
- "org.freedesktop.DBus",
- "NameLost");
-
- } else if (streq(new_owner, a->unique_name)) {
-
- r = sd_bus_message_new_signal(
- b,
- &n,
- "/org/freedesktop/DBus",
- "org.freedesktop.DBus",
- "NameAcquired");
- } else
- return 0;
-
- if (r < 0)
- return r;
-
- r = sd_bus_message_append(n, "s", name);
- if (r < 0)
- return r;
-
- r = bus_message_append_sender(n, "org.freedesktop.DBus");
- if (r < 0)
- return r;
-
- r = bus_seal_synthetic_message(b, n);
- if (r < 0)
- return r;
-
- return sd_bus_send(b, n, NULL);
-}
-
-static int process_policy(sd_bus *a, sd_bus *b, sd_bus_message *m) {
- _cleanup_bus_message_unref_ sd_bus_message *n = NULL;
- int r;
-
- assert(a);
- assert(b);
- assert(m);
-
- if (!sd_bus_message_is_method_call(m, "org.freedesktop.DBus.Properties", "GetAll"))
- return 0;
-
- if (!streq_ptr(m->path, "/org/gnome/DisplayManager/Slave"))
- return 0;
-
- r = sd_bus_message_new_method_errorf(m, &n, SD_BUS_ERROR_ACCESS_DENIED, "gdm, you are stupid");
- if (r < 0)
- return r;
-
- r = bus_message_append_sender(n, "org.freedesktop.DBus");
- if (r < 0) {
- log_error("Failed to append sender to gdm reply: %s", strerror(-r));
- return r;
- }
-
- r = bus_seal_synthetic_message(b, n);
- if (r < 0) {
- log_error("Failed to seal gdm reply: %s", strerror(-r));
- return r;
- }
-
- r = sd_bus_send(b, n, NULL);
- if (r < 0) {
- log_error("Failed to send gdm reply: %s", strerror(-r));
- return r;
- }
-
- return 1;
-}
-
-static int process_driver(sd_bus *a, sd_bus *b, sd_bus_message *m) {
- int r;
-
- assert(a);
- assert(b);
- assert(m);
-
- if (!streq_ptr(sd_bus_message_get_destination(m), "org.freedesktop.DBus"))
- return 0;
-
- if (sd_bus_message_is_method_call(m, "org.freedesktop.DBus", "AddMatch")) {
- const char *match;
-
- r = sd_bus_message_read(m, "s", &match);
- if (r < 0)
- return r;
-
- r = sd_bus_add_match(a, match, NULL, NULL);
- if (r < 0)
- return r;
-
- return sd_bus_reply_method_return(m, NULL);
-
- } else if (sd_bus_message_is_method_call(m, "org.freedesktop.DBus", "RemoveMatch")) {
- const char *match;
-
- r = sd_bus_message_read(m, "s", &match);
- if (r < 0)
- return r;
-
- r = sd_bus_remove_match(a, match, NULL, NULL);
- if (r < 0)
- return r;
-
- return sd_bus_reply_method_return(m, NULL);
- } else
- return 0;
-
- return r;
-}
-
-static int process_hello(sd_bus *a, sd_bus *b, sd_bus_message *m, bool *got_hello) {
- _cleanup_bus_message_unref_ sd_bus_message *n = NULL;
- bool is_hello;
- int r;
-
- assert(a);
- assert(b);
- assert(m);
- assert(got_hello);
-
- /* As reaction to hello we need to respond with two messages:
- * the callback reply and the NameAcquired for the unique
- * name, since hello is otherwise obsolete on kdbus. */
-
- is_hello =
- sd_bus_message_is_method_call(m, "org.freedesktop.DBus", "Hello") &&
- streq_ptr(m->destination, "org.freedesktop.DBus");
-
- if (!is_hello) {
-
- if (*got_hello)
- return 0;
-
- log_error("First packet isn't hello (it's %s.%s), aborting.", m->interface, m->member);
- return -EIO;
- }
-
- if (*got_hello) {
- log_error("Got duplicate hello, aborting.");
- return -EIO;
- }
-
- *got_hello = true;
-
- if (!a->is_kernel)
- return 0;
-
- r = sd_bus_message_new_method_return(m, &n);
- if (r < 0) {
- log_error("Failed to generate HELLO reply: %s", strerror(-r));
- return r;
- }
-
- r = sd_bus_message_append(n, "s", a->unique_name);
- if (r < 0) {
- log_error("Failed to append unique name to HELLO reply: %s", strerror(-r));
- return r;
- }
-
- r = bus_message_append_sender(n, "org.freedesktop.DBus");
- if (r < 0) {
- log_error("Failed to append sender to HELLO reply: %s", strerror(-r));
- return r;
- }
-
- r = bus_seal_synthetic_message(b, n);
- if (r < 0) {
- log_error("Failed to seal HELLO reply: %s", strerror(-r));
- return r;
- }
-
- r = sd_bus_send(b, n, NULL);
- if (r < 0) {
- log_error("Failed to send HELLO reply: %s", strerror(-r));
- return r;
- }
-
- n = sd_bus_message_unref(n);
- r = sd_bus_message_new_signal(
- b,
- &n,
- "/org/freedesktop/DBus",
- "org.freedesktop.DBus",
- "NameAcquired");
- if (r < 0) {
- log_error("Failed to allocate initial NameAcquired message: %s", strerror(-r));
- return r;
- }
-
- r = sd_bus_message_append(n, "s", a->unique_name);
- if (r < 0) {
- log_error("Failed to append unique name to NameAcquired message: %s", strerror(-r));
- return r;
- }
-
- r = bus_message_append_sender(n, "org.freedesktop.DBus");
- if (r < 0) {
- log_error("Failed to append sender to NameAcquired message: %s", strerror(-r));
- return r;
- }
-
- r = bus_seal_synthetic_message(b, n);
- if (r < 0) {
- log_error("Failed to seal NameAcquired message: %s", strerror(-r));
- return r;
- }
-
- r = sd_bus_send(b, n, NULL);
- if (r < 0) {
- log_error("Failed to send NameAcquired message: %s", strerror(-r));
- return r;
- }
-
- return 1;
-}
-
-static int patch_sender(sd_bus *a, sd_bus_message *m) {
- char **well_known = NULL;
- sd_bus_creds *c;
- int r;
-
- assert(a);
- assert(m);
-
- if (!a->is_kernel)
- return 0;
-
- /* We will change the sender of messages from the bus driver
- * so that they originate from the bus driver. This is a
- * speciality originating from dbus1, where the bus driver did
- * not have a unique id, but only the well-known name. */
-
- c = sd_bus_message_get_creds(m);
- if (!c)
- return 0;
-
- r = sd_bus_creds_get_well_known_names(c, &well_known);
- if (r < 0)
- return r;
-
- if (strv_contains(well_known, "org.freedesktop.DBus"))
- m->sender = "org.freedesktop.DBus";
return 0;
}
int main(int argc, char *argv[]) {
-
- _cleanup_bus_unref_ sd_bus *a = NULL, *b = NULL;
- sd_id128_t server_id;
+ _cleanup_(proxy_freep) Proxy *p = NULL;
int r, in_fd, out_fd;
- bool got_hello = false;
- bool is_unix;
- struct ucred ucred = {};
- _cleanup_free_ char *peersec = NULL;
+ uid_t original_uid;
log_set_target(LOG_TARGET_JOURNAL_OR_KMSG);
log_parse_environment();
goto finish;
}
- is_unix =
- sd_is_socket(in_fd, AF_UNIX, 0, 0) > 0 &&
- sd_is_socket(out_fd, AF_UNIX, 0, 0) > 0;
-
- if (is_unix) {
- getpeercred(in_fd, &ucred);
- getpeersec(in_fd, &peersec);
- }
-
- r = sd_bus_new(&a);
- if (r < 0) {
- log_error("Failed to allocate bus: %s", strerror(-r));
- goto finish;
- }
-
- r = sd_bus_set_name(a, "sd-proxy");
- if (r < 0) {
- log_error("Failed to set bus name: %s", strerror(-r));
- goto finish;
- }
-
- r = sd_bus_set_address(a, arg_address);
- if (r < 0) {
- log_error("Failed to set address to connect to: %s", strerror(-r));
- goto finish;
- }
-
- r = sd_bus_negotiate_fds(a, is_unix);
- if (r < 0) {
- log_error("Failed to set FD negotiation: %s", strerror(-r));
- goto finish;
- }
-
- if (ucred.pid > 0) {
- a->fake_creds.pid = ucred.pid;
- a->fake_creds.uid = ucred.uid;
- a->fake_creds.gid = ucred.gid;
- a->fake_creds_valid = true;
- }
-
- if (peersec) {
- a->fake_label = peersec;
- peersec = NULL;
- }
-
- a->manual_peer_interface = true;
-
- r = sd_bus_start(a);
- if (r < 0) {
- log_error("Failed to start bus client: %s", strerror(-r));
- goto finish;
- }
-
- r = sd_bus_get_server_id(a, &server_id);
- if (r < 0) {
- log_error("Failed to get server ID: %s", strerror(-r));
- goto finish;
- }
-
- r = sd_bus_new(&b);
- if (r < 0) {
- log_error("Failed to allocate bus: %s", strerror(-r));
- goto finish;
- }
-
- r = sd_bus_set_fd(b, in_fd, out_fd);
- if (r < 0) {
- log_error("Failed to set fds: %s", strerror(-r));
- goto finish;
- }
-
- r = sd_bus_set_server(b, 1, server_id);
- if (r < 0) {
- log_error("Failed to set server mode: %s", strerror(-r));
- goto finish;
- }
+ original_uid = getuid();
- r = sd_bus_negotiate_fds(b, is_unix);
- if (r < 0) {
- log_error("Failed to set FD negotiation: %s", strerror(-r));
- goto finish;
- }
+ if (arg_drop_privileges) {
+ const char *user = "systemd-bus-proxy";
+ uid_t uid;
+ gid_t gid;
- r = sd_bus_set_anonymous(b, true);
- if (r < 0) {
- log_error("Failed to set anonymous authentication: %s", strerror(-r));
- goto finish;
- }
-
- b->manual_peer_interface = true;
-
- r = sd_bus_start(b);
- if (r < 0) {
- log_error("Failed to start bus client: %s", strerror(-r));
- goto finish;
- }
-
- r = rename_service(a, b);
- if (r < 0)
- log_debug("Failed to rename process: %s", strerror(-r));
-
- if (a->is_kernel) {
- _cleanup_free_ char *match = NULL;
- const char *unique;
-
- r = sd_bus_get_unique_name(a, &unique);
- if (r < 0) {
- log_error("Failed to get unique name: %s", strerror(-r));
- goto finish;
- }
-
- match = strjoin("type='signal',"
- "sender='org.freedesktop.DBus',"
- "path='/org/freedesktop/DBus',"
- "interface='org.freedesktop.DBus',"
- "member='NameOwnerChanged',"
- "arg1='",
- unique,
- "'",
- NULL);
- if (!match) {
- log_oom();
- goto finish;
- }
-
- r = sd_bus_add_match(a, match, NULL, NULL);
+ r = get_user_creds(&user, &uid, &gid, NULL, NULL);
if (r < 0) {
- log_error("Failed to add match for NameLost: %s", strerror(-r));
+ log_error_errno(r, "Cannot resolve user name %s: %m", user);
goto finish;
}
- free(match);
- match = strjoin("type='signal',"
- "sender='org.freedesktop.DBus',"
- "path='/org/freedesktop/DBus',"
- "interface='org.freedesktop.DBus',"
- "member='NameOwnerChanged',"
- "arg2='",
- unique,
- "'",
- NULL);
- if (!match) {
- log_oom();
- goto finish;
- }
-
- r = sd_bus_add_match(a, match, NULL, NULL);
- if (r < 0) {
- log_error("Failed to add match for NameAcquired: %s", strerror(-r));
+ r = drop_privileges(uid, gid, 1ULL << CAP_IPC_OWNER);
+ if (r < 0)
goto finish;
- }
}
- for (;;) {
- _cleanup_bus_message_unref_ sd_bus_message *m = NULL;
- int events_a, events_b, fd;
- uint64_t timeout_a, timeout_b, t;
- struct timespec _ts, *ts;
- struct pollfd *pollfd;
- int k;
-
- if (got_hello) {
- r = sd_bus_process(a, &m);
- if (r < 0) {
- /* treat 'connection reset by peer' as clean exit condition */
- if (r == -ECONNRESET)
- r = 0;
- else
- log_error("Failed to process bus a: %s", strerror(-r));
-
- goto finish;
- }
-
- if (m) {
- /* We officially got EOF, let's quit */
- if (sd_bus_message_is_signal(m, "org.freedesktop.DBus.Local", "Disconnected")) {
- r = 0;
- goto finish;
- }
-
- k = synthesize_name_acquired(a, b, m);
- if (k < 0) {
- r = k;
- log_error("Failed to synthesize message: %s", strerror(-r));
- goto finish;
- }
-
- patch_sender(a, m);
-
- k = sd_bus_send(b, m, NULL);
- if (k < 0) {
- if (k == -ECONNRESET)
- r = 0;
- else {
- r = k;
- log_error("Failed to send message: %s", strerror(-r));
- }
-
- goto finish;
- }
- }
-
- if (r > 0)
- continue;
- }
-
- r = sd_bus_process(b, &m);
- if (r < 0) {
- /* treat 'connection reset by peer' as clean exit condition */
- if (r == -ECONNRESET)
- r = 0;
- else
- log_error("Failed to process bus b: %s", strerror(-r));
-
- goto finish;
- }
-
- if (m) {
- /* We officially got EOF, let's quit */
- if (sd_bus_message_is_signal(m, "org.freedesktop.DBus.Local", "Disconnected")) {
- r = 0;
- goto finish;
- }
-
- k = process_hello(a, b, m, &got_hello);
- if (k < 0) {
- r = k;
- log_error("Failed to process HELLO: %s", strerror(-r));
- goto finish;
- }
-
- if (k > 0)
- r = k;
- else {
- k = process_policy(a, b, m);
- if (k < 0) {
- r = k;
- log_error("Failed to process policy: %s", strerror(-r));
- goto finish;
- }
-
- k = process_driver(a, b, m);
- if (k < 0) {
- r = k;
- log_error("Failed to process driver calls: %s", strerror(-r));
- goto finish;
- }
-
- if (k > 0)
- r = k;
- else {
- k = sd_bus_send(a, m, NULL);
- if (k < 0) {
- if (r == -ECONNRESET)
- r = 0;
- else {
- r = k;
- log_error("Failed to send message: %s", strerror(-r));
- }
-
- goto finish;
- }
- }
- }
- }
-
- if (r > 0)
- continue;
-
- fd = sd_bus_get_fd(a);
- if (fd < 0) {
- log_error("Failed to get fd: %s", strerror(-r));
- goto finish;
- }
-
- events_a = sd_bus_get_events(a);
- if (events_a < 0) {
- log_error("Failed to get events mask: %s", strerror(-r));
- goto finish;
- }
-
- r = sd_bus_get_timeout(a, &timeout_a);
- if (r < 0) {
- log_error("Failed to get timeout: %s", strerror(-r));
- goto finish;
- }
-
- events_b = sd_bus_get_events(b);
- if (events_b < 0) {
- log_error("Failed to get events mask: %s", strerror(-r));
- goto finish;
- }
-
- r = sd_bus_get_timeout(b, &timeout_b);
- if (r < 0) {
- log_error("Failed to get timeout: %s", strerror(-r));
- goto finish;
- }
-
- t = timeout_a;
- if (t == (uint64_t) -1 || (timeout_b != (uint64_t) -1 && timeout_b < timeout_a))
- t = timeout_b;
-
- if (t == (uint64_t) -1)
- ts = NULL;
- else {
- usec_t nw;
+ r = proxy_new(&p, in_fd, out_fd, arg_address);
+ if (r < 0)
+ goto finish;
- nw = now(CLOCK_MONOTONIC);
- if (t > nw)
- t -= nw;
- else
- t = 0;
+ r = proxy_load_policy(p, arg_configuration);
+ if (r < 0)
+ goto finish;
- ts = timespec_store(&_ts, t);
- }
+ r = proxy_hello_policy(p, original_uid);
+ if (r < 0)
+ goto finish;
- pollfd = (struct pollfd[3]) {
- {.fd = fd, .events = events_a, },
- {.fd = in_fd, .events = events_b & POLLIN, },
- {.fd = out_fd, .events = events_b & POLLOUT, }
- };
+ r = rename_service(p->dest_bus, p->local_bus);
+ if (r < 0)
+ log_debug_errno(r, "Failed to rename process: %m");
- r = ppoll(pollfd, 3, ts, NULL);
- if (r < 0) {
- log_error("ppoll() failed: %m");
- goto finish;
- }
- }
+ r = proxy_run(p);
finish:
- sd_bus_flush(a);
- sd_bus_flush(b);
+ sd_notify(false,
+ "STOPPING=1\n"
+ "STATUS=Shutting down.");
+
+ strv_free(arg_configuration);
+ free(arg_address);
return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
}