bus-proxy: factor out code for driver handling and message synthesis

Move synthesize_*() into synthesize.c and bus_proxy_process_driver() into
driver.c for better code separation.

1 files changed, 599 insertions, 0 deletions

diff --git a/src/bus-proxyd/driver.c b/src/bus-proxyd/driver.c
new file mode 100644
index 0000000000..c1f7fc4a3c
--- /dev/null
+++ b/src/bus-proxyd/driver.c
@@ -0,0 +1,599 @@
+/*-*- 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 <http://www.gnu.org/licenses/>.
+***/
+
+#include <sys/types.h>
+#include <unistd.h>
+#include <string.h>
+#include <errno.h>
+#include <stddef.h>
+
+#include "log.h"
+#include "util.h"
+#include "sd-bus.h"
+#include "bus-internal.h"
+#include "bus-message.h"
+#include "bus-util.h"
+#include "build.h"
+#include "strv.h"
+#include "def.h"
+#include "capability.h"
+#include "bus-control.h"
+#include "set.h"
+#include "driver.h"
+#include "synthesize.h"
+
+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);
+
+        r = sd_bus_get_name_creds(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);
+}
+
+int bus_proxy_process_driver(sd_bus *a, sd_bus *b, sd_bus_message *m, Policy *policy, const struct ucred *ucred, Set *owned_names) {
+        int r;
+
+        assert(a);
+        assert(b);
+        assert(m);
+
+        if (!a->is_kernel)
+                return 0;
+
+        if (!streq_ptr(sd_bus_message_get_destination(m), "org.freedesktop.DBus"))
+                return 0;
+
+        /* The "Hello()" call is is handled in process_hello() */
+
+        if (sd_bus_message_is_method_call(m, "org.freedesktop.DBus.Introspectable", "Introspect")) {
+
+                if (!sd_bus_message_has_signature(m, ""))
+                        return synthetic_reply_method_error(m, &SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_INVALID_ARGS, "Invalid parameters"));
+
+                return synthetic_reply_method_return(m, "s",
+                        "<!DOCTYPE node PUBLIC \"-//freedesktop//DTD D-BUS Object Introspection 1.0//EN\" "
+                          "\"http://www.freedesktop.org/standards/dbus/1.0/introspect.dtd\">\n"
+                        "<node>\n"
+                        " <interface name=\"org.freedesktop.DBus.Introspectable\">\n"
+                        "  <method name=\"Introspect\">\n"
+                        "   <arg name=\"data\" type=\"s\" direction=\"out\"/>\n"
+                        "  </method>\n"
+                        " </interface>\n"
+                        " <interface name=\"org.freedesktop.DBus\">\n"
+                        "  <method name=\"AddMatch\">\n"
+                        "   <arg type=\"s\" direction=\"in\"/>\n"
+                        "  </method>\n"
+                        "  <method name=\"RemoveMatch\">\n"
+                        "   <arg type=\"s\" direction=\"in\"/>\n"
+                        "  </method>\n"
+                        "  <method name=\"GetConnectionSELinuxSecurityContext\">\n"
+                        "   <arg type=\"s\" direction=\"in\"/>\n"
+                        "   <arg type=\"ay\" direction=\"out\"/>\n"
+                        "  </method>\n"
+                        "  <method name=\"GetConnectionUnixProcessID\">\n"
+                        "   <arg type=\"s\" direction=\"in\"/>\n"
+                        "   <arg type=\"u\" direction=\"out\"/>\n"
+                        "  </method>\n"
+                        "  <method name=\"GetConnectionUnixUser\">\n"
+                        "   <arg type=\"s\" direction=\"in\"/>\n"
+                        "   <arg type=\"u\" direction=\"out\"/>\n"
+                        "  </method>\n"
+                        "  <method name=\"GetId\">\n"
+                        "   <arg type=\"s\" direction=\"out\"/>\n"
+                        "  </method>\n"
+                        "  <method name=\"GetNameOwner\">\n"
+                        "   <arg type=\"s\" direction=\"in\"/>\n"
+                        "   <arg type=\"s\" direction=\"out\"/>\n"
+                        "  </method>\n"
+                        "  <method name=\"Hello\">\n"
+                        "   <arg type=\"s\" direction=\"out\"/>\n"
+                        "  </method>\n"
+                        "  <method name=\"ListActivatableNames\">\n"
+                        "   <arg type=\"as\" direction=\"out\"/>\n"
+                        "  </method>\n"
+                        "  <method name=\"ListNames\">\n"
+                        "   <arg type=\"as\" direction=\"out\"/>\n"
+                        "  </method>\n"
+                        "  <method name=\"ListQueuedOwners\">\n"
+                        "   <arg type=\"s\" direction=\"in\"/>\n"
+                        "   <arg type=\"as\" direction=\"out\"/>\n"
+                        "  </method>\n"
+                        "  <method name=\"NameHasOwner\">\n"
+                        "   <arg type=\"s\" direction=\"in\"/>\n"
+                        "   <arg type=\"b\" direction=\"out\"/>\n"
+                        "  </method>\n"
+                        "  <method name=\"ReleaseName\">\n"
+                        "   <arg type=\"s\" direction=\"in\"/>\n"
+                        "   <arg type=\"u\" direction=\"out\"/>\n"
+                        "  </method>\n"
+                        "  <method name=\"ReloadConfig\">\n"
+                        "  </method>\n"
+                        "  <method name=\"RequestName\">\n"
+                        "   <arg type=\"s\" direction=\"in\"/>\n"
+                        "   <arg type=\"u\" direction=\"in\"/>\n"
+                        "   <arg type=\"u\" direction=\"out\"/>\n"
+                        "  </method>\n"
+                        "  <method name=\"StartServiceByName\">\n"
+                        "   <arg type=\"s\" direction=\"in\"/>\n"
+                        "   <arg type=\"u\" direction=\"in\"/>\n"
+                        "   <arg type=\"u\" direction=\"out\"/>\n"
+                        "  </method>\n"
+                        "  <method name=\"UpdateActivationEnvironment\">\n"
+                        "   <arg type=\"a{ss}\" direction=\"in\"/>\n"
+                        "  </method>\n"
+                        "  <signal name=\"NameAcquired\">\n"
+                        "   <arg type=\"s\"/>\n"
+                        "  </signal>\n"
+                        "  <signal name=\"NameLost\">\n"
+                        "   <arg type=\"s\"/>\n"
+                        "  </signal>\n"
+                        "  <signal name=\"NameOwnerChanged\">\n"
+                        "   <arg type=\"s\"/>\n"
+                        "   <arg type=\"s\"/>\n"
+                        "   <arg type=\"s\"/>\n"
+                        "  </signal>\n"
+                        " </interface>\n"
+                        "</node>\n");
+
+        } else if (sd_bus_message_is_method_call(m, "org.freedesktop.DBus", "AddMatch")) {
+                const char *match;
+
+                if (!sd_bus_message_has_signature(m, "s"))
+                        return synthetic_reply_method_error(m, &SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_INVALID_ARGS, "Invalid parameters"));
+
+                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;
+
+                if (!sd_bus_message_has_signature(m, "s"))
+                        return synthetic_reply_method_error(m, &SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_INVALID_ARGS, "Invalid parameters"));
+
+                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;
+                _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
+
+                if (!sd_bus_message_has_signature(m, "s"))
+                        return synthetic_reply_method_error(m, &SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_INVALID_ARGS, "Invalid parameters"));
+
+                r = get_creds_by_message(a, m, SD_BUS_CREDS_SELINUX_CONTEXT, &creds, &error);
+                if (r < 0)
+                        return synthetic_reply_method_errno(m, r, &error);
+
+                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;
+                _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
+
+                if (!sd_bus_message_has_signature(m, "s"))
+                        return synthetic_reply_method_error(m, &SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_INVALID_ARGS, "Invalid parameters"));
+
+                r = get_creds_by_message(a, m, SD_BUS_CREDS_PID, &creds, &error);
+                if (r < 0)
+                        return synthetic_reply_method_errno(m, r, &error);
+
+                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;
+                _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
+
+                if (!sd_bus_message_has_signature(m, "s"))
+                        return synthetic_reply_method_error(m, &SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_INVALID_ARGS, "Invalid parameters"));
+
+                r = get_creds_by_message(a, m, SD_BUS_CREDS_UID, &creds, &error);
+                if (r < 0)
+                        return synthetic_reply_method_errno(m, r, &error);
+
+                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];
+
+                if (!sd_bus_message_has_signature(m, ""))
+                        return synthetic_reply_method_error(m, &SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_INVALID_ARGS, "Invalid parameters"));
+
+                r = sd_bus_get_bus_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;
+
+                if (!sd_bus_message_has_signature(m, "s"))
+                        return synthetic_reply_method_error(m, &SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_INVALID_ARGS, "Invalid parameters"));
+
+                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);
+
+        } else if (sd_bus_message_is_method_call(m, "org.freedesktop.DBus", "ListActivatableNames")) {
+                _cleanup_strv_free_ char **names = NULL;
+
+                if (!sd_bus_message_has_signature(m, ""))
+                        return synthetic_reply_method_error(m, &SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_INVALID_ARGS, "Invalid parameters"));
+
+                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;
+
+                if (!sd_bus_message_has_signature(m, ""))
+                        return synthetic_reply_method_error(m, &SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_INVALID_ARGS, "Invalid parameters"));
+
+                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_name_info *name;
+                _cleanup_strv_free_ char **owners = NULL;
+                _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
+                char *arg0;
+                int err = 0;
+
+                if (!sd_bus_message_has_signature(m, "s"))
+                        return synthetic_reply_method_error(m, &SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_INVALID_ARGS, "Invalid parameters"));
+
+                r = sd_bus_message_read(m, "s", &arg0);
+                if (r < 0)
+                        return synthetic_reply_method_errno(m, r, NULL);
+
+                r = sd_bus_get_name_creds(a, arg0, 0, NULL);
+                if (r == -ESRCH || r == -ENXIO) {
+                        sd_bus_error_setf(&error, SD_BUS_ERROR_NAME_HAS_NO_OWNER, "Could not get owners of name '%s': no such name.", arg0);
+                        return synthetic_reply_method_errno(m, r, &error);
+                }
+                if (r < 0)
+                        return synthetic_reply_method_errno(m, r, 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) {
+                        const char *entry_name = NULL;
+                        struct kdbus_item *item;
+                        char *n;
+
+                        KDBUS_ITEM_FOREACH(item, name, items)
+                                if (item->type == KDBUS_ITEM_OWNED_NAME)
+                                        entry_name = item->name.name;
+
+                        if (!streq_ptr(entry_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 = bus_kernel_cmd_free(a, 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;
+
+                if (!sd_bus_message_has_signature(m, "s"))
+                        return synthetic_reply_method_error(m, &SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_INVALID_ARGS, "Invalid parameters"));
+
+                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, "b", true);
+
+                r = sd_bus_get_name_creds(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;
+
+                if (!sd_bus_message_has_signature(m, "s"))
+                        return synthetic_reply_method_error(m, &SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_INVALID_ARGS, "Invalid parameters"));
+
+                r = sd_bus_message_read(m, "s", &name);
+                if (r < 0)
+                        return synthetic_reply_method_errno(m, r, 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);
+                }
+
+                set_remove(owned_names, (char*) name);
+
+                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;
+
+                if (!sd_bus_message_has_signature(m, ""))
+                        return synthetic_reply_method_error(m, &SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_INVALID_ARGS, "Invalid parameters"));
+
+                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, param;
+                bool in_queue;
+
+                if (!sd_bus_message_has_signature(m, "su"))
+                        return synthetic_reply_method_error(m, &SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_INVALID_ARGS, "Invalid parameters"));
+
+                r = sd_bus_message_read(m, "su", &name, &flags);
+                if (r < 0)
+                        return synthetic_reply_method_errno(m, r, NULL);
+
+                if (policy && !policy_check_own(policy, ucred->uid, ucred->gid, name))
+                        return synthetic_reply_method_errno(m, -EPERM, 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);
+
+                param = 0;
+                if (flags & BUS_NAME_ALLOW_REPLACEMENT)
+                        param |= SD_BUS_NAME_ALLOW_REPLACEMENT;
+                if (flags & BUS_NAME_REPLACE_EXISTING)
+                        param |= SD_BUS_NAME_REPLACE_EXISTING;
+                if (!(flags & BUS_NAME_DO_NOT_QUEUE))
+                        param |= SD_BUS_NAME_QUEUE;
+
+                r = set_put_strdup(owned_names, name);
+                if (r < 0)
+                        return synthetic_reply_method_errno(m, r, NULL);
+
+                r = sd_bus_request_name(a, name, param);
+                if (r < 0) {
+                        if (r == -EALREADY)
+                                return synthetic_reply_method_return(m, "u", BUS_NAME_ALREADY_OWNER);
+
+                        set_remove(owned_names, (char*) name);
+
+                        if (r == -EEXIST)
+                                return synthetic_reply_method_return(m, "u", BUS_NAME_EXISTS);
+                        return synthetic_reply_method_errno(m, r, NULL);
+                }
+
+                in_queue = (r == 0);
+
+                if (in_queue)
+                        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;
+
+                if (!sd_bus_message_has_signature(m, "su"))
+                        return synthetic_reply_method_error(m, &SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_INVALID_ARGS, "Invalid parameters"));
+
+                r = sd_bus_message_read(m, "su", &name, &flags);
+                if (r < 0)
+                        return synthetic_reply_method_errno(m, r, NULL);
+
+                if (flags != 0)
+                        return synthetic_reply_method_errno(m, -EINVAL, NULL);
+
+                r = sd_bus_get_name_creds(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 (!sd_bus_message_has_signature(m, "a{ss}"))
+                        return synthetic_reply_method_error(m, &SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_INVALID_ARGS, "Invalid parameters"));
+
+                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);
+        }
+}