/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ /*** 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 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 "log.h" #include "util.h" #include "socket-util.h" #include "sd-daemon.h" #include "sd-bus.h" #include "bus-internal.h" #include "bus-message.h" #include "bus-util.h" #include "bus-internal.h" #include "build.h" #include "strv.h" #include "def.h" #include "capability.h" #include "bus-policy.h" static const char *arg_address = DEFAULT_SYSTEM_BUS_PATH; static char *arg_command_line_buffer = NULL; static bool arg_drop_privileges = false; 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" " --drop-privileges Drop privileges\n" " --address=ADDRESS Connect to the bus specified by ADDRESS\n" " (default: " DEFAULT_SYSTEM_BUS_PATH ")\n", program_invocation_short_name); return 0; } static int parse_argv(int argc, char *argv[]) { enum { ARG_VERSION = 0x100, ARG_ADDRESS, ARG_DROP_PRIVILEGES, }; static const struct option options[] = { { "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 }, { NULL, 0, NULL, 0 }, }; int c; assert(argc >= 0); assert(argv); while ((c = getopt_long(argc, argv, "h", options, NULL)) >= 0) { switch (c) { case 'h': help(); return 0; case ARG_VERSION: puts(PACKAGE_STRING); puts(SYSTEMD_FEATURES); return 0; case ARG_ADDRESS: arg_address = optarg; break; case ARG_DROP_PRIVILEGES: arg_drop_privileges = true; 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)) { log_error("Too many arguments"); return -EINVAL; } return 1; } static int rename_service(sd_bus *a, sd_bus *b) { _cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL; _cleanup_free_ char *p = NULL, *name = NULL; const char *comm; char **cmdline; uid_t uid; pid_t pid; int r; 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); if (r < 0) return r; r = sd_bus_creds_get_uid(creds, &uid); if (r < 0) return r; r = sd_bus_creds_get_pid(creds, &pid); if (r < 0) return r; r = sd_bus_creds_get_cmdline(creds, &cmdline); if (r < 0) return r; r = sd_bus_creds_get_comm(creds, &comm); if (r < 0) return r; name = uid_to_name(uid); if (!name) return -ENOMEM; p = strv_join(cmdline, " "); if (!p) return -ENOMEM; /* The status string gets the full command line ... */ sd_notifyf(false, "STATUS=Processing requests from client PID "PID_FMT" (%s); UID "UID_FMT" (%s)", pid, p, uid, name); /* ... and the argv line only the short comm */ if (arg_command_line_buffer) { size_t m, w; m = strlen(arg_command_line_buffer); w = snprintf(arg_command_line_buffer, m, "[PID "PID_FMT"/%s; UID "UID_FMT"/%s]", pid, comm, uid, name); if (m > w) memzero(arg_command_line_buffer + w, m - w); } log_debug("Running on behalf of PID "PID_FMT" (%s), UID "UID_FMT" (%s), %s", 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 synthetic_driver_send(sd_bus *b, sd_bus_message *m) { int r; assert(b); assert(m); r = bus_message_append_sender(m, "org.freedesktop.DBus"); if (r < 0) return r; r = bus_seal_synthetic_message(b, m); if (r < 0) return r; return sd_bus_send(b, m, NULL); } static int synthetic_reply_method_error(sd_bus_message *call, const sd_bus_error *e) { _cleanup_bus_message_unref_ sd_bus_message *m = NULL; int r; if (call->header->flags & BUS_MESSAGE_NO_REPLY_EXPECTED) return 0; r = sd_bus_message_new_method_error(call, &m, e); if (r < 0) return r; return synthetic_driver_send(call->bus, m); } static int synthetic_reply_method_errno(sd_bus_message *call, int error, const sd_bus_error *p) { _cleanup_bus_error_free_ sd_bus_error berror = SD_BUS_ERROR_NULL; if (call->header->flags & BUS_MESSAGE_NO_REPLY_EXPECTED) return 0; if (sd_bus_error_is_set(p)) return synthetic_reply_method_error(call, p); sd_bus_error_set_errno(&berror, error); return synthetic_reply_method_error(call, &berror); } static int synthetic_reply_method_return(sd_bus_message *call, const char *types, ...) { _cleanup_bus_message_unref_ sd_bus_message *m = NULL; int r; if (call->header->flags & BUS_MESSAGE_NO_REPLY_EXPECTED) return 0; r = sd_bus_message_new_method_return(call, &m); if (r < 0) return r; if (!isempty(types)) { va_list ap; va_start(ap, types); r = bus_message_append_ap(m, types, ap); va_end(ap); if (r < 0) return r; } return synthetic_driver_send(call->bus, m); } static int synthetic_reply_return_strv(sd_bus_message *call, char **l) { _cleanup_bus_message_unref_ sd_bus_message *m = NULL; int r; r = sd_bus_message_new_method_return(call, &m); if (r < 0) return synthetic_reply_method_errno(call, r, NULL); r = sd_bus_message_append_strv(m, l); if (r < 0) return synthetic_reply_method_errno(call, r, NULL); return synthetic_driver_send(call->bus, m); } static int get_creds_by_name(sd_bus *bus, const char *name, uint64_t mask, sd_bus_creds **_creds, sd_bus_error *error) { _cleanup_bus_creds_unref_ sd_bus_creds *c = NULL; int r; assert(bus); assert(name); assert(_creds); assert_return(service_name_is_valid(name), -EINVAL); r = sd_bus_get_owner(bus, name, mask, &c); if (r == -ESRCH || 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 get_creds_by_message(sd_bus *bus, sd_bus_message *m, uint64_t mask, sd_bus_creds **_creds, sd_bus_error *error) { const char *name; int r; assert(bus); assert(m); assert(_creds); r = sd_bus_message_read(m, "s", &name); if (r < 0) return r; return get_creds_by_name(bus, name, mask, _creds, error); } static int peer_is_privileged(sd_bus *bus, sd_bus_message *m) { _cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL; uid_t uid; int r; r = get_creds_by_message(bus, m, SD_BUS_CREDS_UID, &creds, NULL); if (r < 0) return r; r = sd_bus_creds_get_uid(creds, &uid); if (r < 0) return r; r = sd_bus_creds_has_effective_cap(creds, CAP_SYS_ADMIN); if (r > 0) return true; if (uid == getuid()) return true; return false; } 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.Introspectable", "Introspect")) { if (0 && !isempty(sd_bus_message_get_signature(m, true))) { _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL; r = sd_bus_error_setf(&error, SD_BUS_ERROR_INVALID_ARGS, "Expected no parameters"); return synthetic_reply_method_errno(m, r, &error); } return synthetic_reply_method_return(m, "s", "\n" "\n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" " \n" "\n"); } else 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 synthetic_reply_method_errno(m, r, NULL); r = sd_bus_add_match(a, NULL, match, NULL, NULL); if (r < 0) return synthetic_reply_method_errno(m, r, NULL); return synthetic_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 synthetic_reply_method_errno(m, r, NULL); r = bus_remove_match_by_string(a, match, NULL, NULL); if (r == 0) return synthetic_reply_method_error(m, &SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_MATCH_RULE_NOT_FOUND, "Match rule not found")); if (r < 0) return synthetic_reply_method_errno(m, r, NULL); return synthetic_reply_method_return(m, NULL); } else if (sd_bus_message_is_method_call(m, "org.freedesktop.DBus", "GetConnectionSELinuxSecurityContext")) { _cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL; r = get_creds_by_message(a, m, SD_BUS_CREDS_SELINUX_CONTEXT, &creds, NULL); if (r < 0) return synthetic_reply_method_errno(m, r, NULL); return synthetic_reply_method_return(m, "y", creds->label, strlen(creds->label)); } else if (sd_bus_message_is_method_call(m, "org.freedesktop.DBus", "GetConnectionUnixProcessID")) { _cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL; r = get_creds_by_message(a, m, SD_BUS_CREDS_PID, &creds, NULL); if (r < 0) return synthetic_reply_method_errno(m, r, NULL); return synthetic_reply_method_return(m, "u", (uint32_t) creds->pid); } else if (sd_bus_message_is_method_call(m, "org.freedesktop.DBus", "GetConnectionUnixUser")) { _cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL; r = get_creds_by_message(a, m, SD_BUS_CREDS_UID, &creds, NULL); if (r < 0) return synthetic_reply_method_errno(m, r, NULL); return synthetic_reply_method_return(m, "u", (uint32_t) creds->uid); } else if (sd_bus_message_is_method_call(m, "org.freedesktop.DBus", "GetId")) { sd_id128_t server_id; char buf[SD_ID128_STRING_MAX]; r = sd_bus_get_server_id(a, &server_id); if (r < 0) return synthetic_reply_method_errno(m, r, NULL); return synthetic_reply_method_return(m, "s", sd_id128_to_string(server_id, buf)); } else if (sd_bus_message_is_method_call(m, "org.freedesktop.DBus", "GetNameOwner")) { const char *name; _cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL; _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL; r = sd_bus_message_read(m, "s", &name); if (r < 0) return synthetic_reply_method_errno(m, r, NULL); if (streq(name, "org.freedesktop.DBus")) return synthetic_reply_method_return(m, "s", "org.freedesktop.DBus"); r = get_creds_by_name(a, name, SD_BUS_CREDS_UNIQUE_NAME, &creds, &error); if (r < 0) return synthetic_reply_method_errno(m, r, &error); return synthetic_reply_method_return(m, "s", creds->unique_name); /* "Hello" is handled in process_hello() */ } else if (sd_bus_message_is_method_call(m, "org.freedesktop.DBus", "ListActivatableNames")) { _cleanup_strv_free_ char **names = NULL; r = sd_bus_list_names(a, NULL, &names); if (r < 0) return synthetic_reply_method_errno(m, r, NULL); /* Let's sort the names list to make it stable */ strv_sort(names); return synthetic_reply_return_strv(m, names); } else if (sd_bus_message_is_method_call(m, "org.freedesktop.DBus", "ListNames")) { _cleanup_strv_free_ char **names = NULL; r = sd_bus_list_names(a, &names, NULL); if (r < 0) return synthetic_reply_method_errno(m, r, NULL); r = strv_extend(&names, "org.freedesktop.DBus"); if (r < 0) return synthetic_reply_method_errno(m, r, NULL); /* Let's sort the names list to make it stable */ strv_sort(names); return synthetic_reply_return_strv(m, names); } else if (sd_bus_message_is_method_call(m, "org.freedesktop.DBus", "ListQueuedOwners")) { 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 err = 0; r = sd_bus_message_read(m, "s", &arg0); if (r < 0) return synthetic_reply_method_errno(m, r, NULL); if (service_name_is_valid(arg0) < 0) return synthetic_reply_method_errno(m, -EINVAL, NULL); cmd.flags = KDBUS_NAME_LIST_QUEUED; r = ioctl(a->input_fd, KDBUS_CMD_NAME_LIST, &cmd); if (r < 0) return synthetic_reply_method_errno(m, -errno, NULL); name_list = (struct kdbus_name_list *) ((uint8_t *) a->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) { err = -ENOMEM; break; } r = strv_consume(&owners, n); if (r < 0) { err = r; break; } } r = ioctl(a->input_fd, KDBUS_CMD_FREE, &cmd.offset); if (r < 0) return synthetic_reply_method_errno(m, r, NULL); if (err > 0) return synthetic_reply_method_errno(m, err, NULL); return synthetic_reply_return_strv(m, owners); } else if (sd_bus_message_is_method_call(m, "org.freedesktop.DBus", "NameHasOwner")) { const char *name; r = sd_bus_message_read(m, "s", &name); if (r < 0) return synthetic_reply_method_errno(m, r, NULL); if (service_name_is_valid(name) < 0) return synthetic_reply_method_errno(m, -EINVAL, NULL); if (streq(name, "org.freedesktop.DBus")) return synthetic_reply_method_return(m, "b", true); r = sd_bus_get_owner(a, name, 0, NULL); if (r < 0 && r != -ESRCH && r != -ENXIO) return synthetic_reply_method_errno(m, r, NULL); return synthetic_reply_method_return(m, "b", r >= 0); } else if (sd_bus_message_is_method_call(m, "org.freedesktop.DBus", "ReleaseName")) { const char *name; r = sd_bus_message_read(m, "s", &name); if (r < 0) return synthetic_reply_method_errno(m, r, NULL); if (service_name_is_valid(name) < 0) return synthetic_reply_method_errno(m, -EINVAL, NULL); r = sd_bus_release_name(a, name); if (r < 0) { if (r == -ESRCH) return synthetic_reply_method_return(m, "u", BUS_NAME_NON_EXISTENT); if (r == -EADDRINUSE) return synthetic_reply_method_return(m, "u", BUS_NAME_NOT_OWNER); return synthetic_reply_method_errno(m, r, NULL); } return synthetic_reply_method_return(m, "u", BUS_NAME_RELEASED); } else if (sd_bus_message_is_method_call(m, "org.freedesktop.DBus", "ReloadConfig")) { _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL; r = sd_bus_error_setf(&error, SD_BUS_ERROR_NOT_SUPPORTED, "%s() is not supported", sd_bus_message_get_member(m)); return synthetic_reply_method_errno(m, r, &error); } else if (sd_bus_message_is_method_call(m, "org.freedesktop.DBus", "RequestName")) { const char *name; uint32_t flags; r = sd_bus_message_read(m, "su", &name, &flags); if (r < 0) return synthetic_reply_method_errno(m, r, NULL); if (service_name_is_valid(name) < 0) return synthetic_reply_method_errno(m, -EINVAL, NULL); if ((flags & ~(BUS_NAME_ALLOW_REPLACEMENT|BUS_NAME_REPLACE_EXISTING|BUS_NAME_DO_NOT_QUEUE)) != 0) return synthetic_reply_method_errno(m, -EINVAL, NULL); r = sd_bus_request_name(a, name, flags); if (r < 0) { if (r == -EEXIST) return synthetic_reply_method_return(m, "u", BUS_NAME_EXISTS); if (r == -EALREADY) return synthetic_reply_method_return(m, "u", BUS_NAME_ALREADY_OWNER); return synthetic_reply_method_errno(m, r, NULL); } if (r == 0) return synthetic_reply_method_return(m, "u", BUS_NAME_IN_QUEUE); return synthetic_reply_method_return(m, "u", BUS_NAME_PRIMARY_OWNER); } else if (sd_bus_message_is_method_call(m, "org.freedesktop.DBus", "StartServiceByName")) { _cleanup_bus_message_unref_ sd_bus_message *msg = NULL; const char *name; uint32_t flags; r = sd_bus_message_read(m, "su", &name, &flags); if (r < 0) return synthetic_reply_method_errno(m, r, NULL); if (service_name_is_valid(name) < 0) return synthetic_reply_method_errno(m, -EINVAL, NULL); if (flags != 0) return synthetic_reply_method_errno(m, -EINVAL, NULL); r = sd_bus_get_owner(a, name, 0, NULL); if (r >= 0 || streq(name, "org.freedesktop.DBus")) return synthetic_reply_method_return(m, "u", BUS_START_REPLY_ALREADY_RUNNING); if (r != -ESRCH) return synthetic_reply_method_errno(m, r, NULL); r = sd_bus_message_new_method_call( a, &msg, name, "/", "org.freedesktop.DBus.Peer", "Ping"); if (r < 0) return synthetic_reply_method_errno(m, r, NULL); r = sd_bus_send(a, msg, NULL); if (r < 0) return synthetic_reply_method_errno(m, r, NULL); return synthetic_reply_method_return(m, "u", BUS_START_REPLY_SUCCESS); } else if (sd_bus_message_is_method_call(m, "org.freedesktop.DBus", "UpdateActivationEnvironment")) { _cleanup_bus_message_unref_ sd_bus_message *msg = NULL; _cleanup_strv_free_ char **args = NULL; if (!peer_is_privileged(a, m)) return synthetic_reply_method_errno(m, -EPERM, NULL); r = sd_bus_message_enter_container(m, SD_BUS_TYPE_ARRAY, "{ss}"); if (r < 0) return synthetic_reply_method_errno(m, r, NULL); while ((r = sd_bus_message_enter_container(m, SD_BUS_TYPE_DICT_ENTRY, "ss")) > 0) { _cleanup_free_ char *s = NULL; const char *key; const char *value; r = sd_bus_message_read(m, "ss", &key, &value); if (r < 0) return synthetic_reply_method_errno(m, r, NULL); s = strjoin(key, "=", value, NULL); if (!s) return synthetic_reply_method_errno(m, -ENOMEM, NULL); r = strv_extend(&args, s); if (r < 0) return synthetic_reply_method_errno(m, r, NULL); r = sd_bus_message_exit_container(m); if (r < 0) return synthetic_reply_method_errno(m, r, NULL); } r = sd_bus_message_exit_container(m); if (r < 0) return synthetic_reply_method_errno(m, r, NULL); if (!args) return synthetic_reply_method_errno(m, -EINVAL, NULL); r = sd_bus_message_new_method_call( a, &msg, "org.freedesktop.systemd1", "/org/freedesktop/systemd1", "org.freedesktop.systemd1.Manager", "SetEnvironment"); if (r < 0) return synthetic_reply_method_errno(m, r, NULL); r = sd_bus_message_append_strv(msg, args); if (r < 0) return synthetic_reply_method_errno(m, r, NULL); r = sd_bus_call(a, msg, 0, NULL, NULL); if (r < 0) return synthetic_reply_method_errno(m, r, NULL); return synthetic_reply_method_return(m, NULL); } else { _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL; r = sd_bus_error_setf(&error, SD_BUS_ERROR_UNKNOWN_METHOD, "Unknown method '%s'.", m->member); return synthetic_reply_method_errno(m, r, &error); } } 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; int r, in_fd, out_fd; bool got_hello = false; bool is_unix; struct ucred ucred = {}; _cleanup_free_ char *peersec = NULL; Policy policy = {}; log_set_target(LOG_TARGET_JOURNAL_OR_KMSG); log_parse_environment(); log_open(); r = parse_argv(argc, argv); if (r <= 0) goto finish; r = policy_load(&policy); if (r < 0) { log_error("Failed to load policy: %s", strerror(-r)); goto finish; } /* policy_dump(&policy); */ r = sd_listen_fds(0); if (r == 0) { in_fd = STDIN_FILENO; out_fd = STDOUT_FILENO; } else if (r == 1) { in_fd = SD_LISTEN_FDS_START; out_fd = SD_LISTEN_FDS_START; } else { log_error("Illegal number of file descriptors passed"); 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); } if (arg_drop_privileges) { const char *user = "systemd-bus-proxy"; uid_t uid; gid_t gid; r = get_user_creds(&user, &uid, &gid, NULL, NULL); if (r < 0) { log_error("Cannot resolve user name %s: %s", user, strerror(-r)); goto finish; } r = drop_privileges(uid, gid, 1ULL << CAP_IPC_OWNER); if (r < 0) goto finish; } 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; } r = sd_bus_negotiate_fds(b, is_unix); if (r < 0) { log_error("Failed to set FD negotiation: %s", strerror(-r)); goto finish; } 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, NULL, match, NULL, NULL); if (r < 0) { log_error("Failed to add match for NameLost: %s", strerror(-r)); 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, NULL, match, NULL, NULL); if (r < 0) { log_error("Failed to add match for NameAcquired: %s", strerror(-r)); 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; nw = now(CLOCK_MONOTONIC); if (t > nw) t -= nw; else t = 0; ts = timespec_store(&_ts, t); } pollfd = (struct pollfd[3]) { {.fd = fd, .events = events_a, }, {.fd = in_fd, .events = events_b & POLLIN, }, {.fd = out_fd, .events = events_b & POLLOUT, } }; r = ppoll(pollfd, 3, ts, NULL); if (r < 0) { log_error("ppoll() failed: %m"); goto finish; } } finish: sd_bus_flush(a); sd_bus_flush(b); policy_free(&policy); return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS; }