bus: add generator that turns old dbus1 activation files into .busname + .service units

1 files changed, 279 insertions, 0 deletions

diff --git a/src/dbus1-generator/dbus1-generator.c b/src/dbus1-generator/dbus1-generator.c
new file mode 100644
index 000000000..93c6392f8
--- /dev/null
+++ b/src/dbus1-generator/dbus1-generator.c
@@ -0,0 +1,279 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2013 Lennart Poettering
+
+  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 "util.h"
+#include "conf-parser.h"
+#include "special.h"
+#include "mkdir.h"
+#include "bus-util.h"
+#include "bus-internal.h"
+#include "unit-name.h"
+#include "cgroup-util.h"
+
+static const char *arg_dest = "/tmp";
+
+static int create_dbus_files(
+                const char *path,
+                const char *name,
+                const char *service,
+                const char *exec,
+                const char *user,
+                const char *type) {
+
+        _cleanup_free_ char *b = NULL, *s = NULL, *lnk = NULL;
+        _cleanup_fclose_ FILE *f = NULL;
+
+        assert(path);
+        assert(name);
+
+        if (!service) {
+                _cleanup_free_ char *a = NULL;
+
+                s = strjoin("dbus-", name, ".service", NULL);
+                if (!s)
+                        return log_oom();
+
+                a = strjoin(arg_dest, "/", s, NULL);
+                if (!a)
+                        return log_oom();
+
+                f = fopen(a, "wxe");
+                if (!f) {
+                        log_error("Failed to create %s: %m", a);
+                        return -errno;
+                }
+
+                fprintf(f,
+                        "# Automatically generated by systemd-dbus1-generator\n\n"
+                        "[Unit]\n"
+                        "Source=%s\n"
+                        "Description=DBUS1: %s\n\n"
+                        "[Service]\n"
+                        "ExecStart=%s\n"
+                        "Type=dbus\n"
+                        "BusName=%s\n",
+                        path,
+                        name,
+                        exec,
+                        name);
+
+                if (user)
+                        fprintf(f, "User=%s\n", user);
+
+
+                if (type) {
+                        fprintf(f, "Environment=DBUS_STARTER_BUS_TYPE=%s\n", type);
+
+                        if (streq(type, "system"))
+                                fprintf(f, "Environment=DBUS_STARTER_ADDRESS=kernel:/dev/kdbus/0-system\n");
+                        else if (streq(type, "session"))
+                                fprintf(f, "Environment=DBUS_STARTER_ADDRESS=kernel:/dev/kdbus/%lu-user\n", (unsigned long) getuid());
+                }
+
+                fflush(f);
+                if (ferror(f)) {
+                        log_error("Failed to write %s: %m", a);
+                        return -errno;
+                }
+
+                service = s;
+        }
+
+        b = strjoin(arg_dest, "/", name, ".busname", NULL);
+        if (!b)
+                return log_oom();
+
+        f = fopen(b, "wxe");
+        if (!f) {
+                log_error("Failed to create %s: %m", b);
+                return -errno;
+        }
+
+        fprintf(f,
+                "# Automatically generated by systemd-dbus1-generator\n\n"
+                "[Unit]\n"
+                "Source=%s\n"
+                "Description=DBUS1: %s\n\n"
+                "[BusName]\n"
+                "Name=%s\n"
+                "Service=%s\n",
+                path,
+                name,
+                name,
+                service);
+
+        fflush(f);
+        if (ferror(f)) {
+                log_error("Failed to write %s: %m", b);
+                return -errno;
+        }
+
+        lnk = strjoin(arg_dest, "/" SPECIAL_BUSNAMES_TARGET ".wants/", name, ".busname", NULL);
+        if (!lnk)
+                return log_oom();
+
+        mkdir_parents_label(lnk, 0755);
+        if (symlink(b, lnk)) {
+                log_error("Failed to create symlinks %s: %m", lnk);
+                return -errno;
+        }
+
+        return 0;
+}
+
+static int add_dbus(const char *path, const char *fname, const char *type) {
+        _cleanup_free_ char *name = NULL, *exec = NULL, *user = NULL, *service = NULL;
+
+        ConfigTableItem table[] = {
+                { "D-BUS Service", "Name", config_parse_string, 0, &name },
+                { "D-BUS Service", "Exec", config_parse_string, 0, &exec },
+                { "D-BUS Service", "User", config_parse_string, 0, &user },
+                { "D-BUS Service", "SystemdService", config_parse_string, 0, &service },
+        };
+
+        _cleanup_fclose_ FILE *f = NULL;
+        _cleanup_free_ char *p = NULL;
+        int r;
+
+        assert(path);
+        assert(fname);
+
+        p = strjoin(path, "/", fname, NULL);
+        if (!p)
+                return log_oom();
+
+        f = fopen(p, "re");
+        if (!f) {
+                if (errno == -ENOENT)
+                        return 0;
+
+                log_error("Failed to read %s: %m", p);
+                return -errno;
+        }
+
+        r = config_parse(NULL, p, f, "D-BUS Service\0", config_item_table_lookup, table, true, false, NULL);
+        if (r < 0)
+                return r;
+
+        if (!name) {
+                log_warning("Activation file %s lacks name setting, ignoring.", p);
+                return 0;
+        }
+
+        if (!service_name_is_valid(name)) {
+                log_warning("Bus service name %s is not valid, ignoring.", name);
+                return 0;
+        }
+
+        if (service) {
+                if (!unit_name_is_valid(service, false)) {
+                        log_warning("Unit name %s is not valid, ignoring.", service);
+                        return 0;
+                }
+                if (!endswith(service, ".service")) {
+                        log_warning("Bus names can only activate services, ignoring %s.", p);
+                        return 0;
+                }
+        } else {
+                if (!exec) {
+                        log_warning("Neither service name nor binary path specified, ignoring %s.", p);
+                        return 0;
+                }
+
+                if (exec[0] != '/') {
+                        log_warning("Exec= in %s does not start with an absolute path, ignoring.", p);
+                        return 0;
+                }
+        }
+
+        return create_dbus_files(p, name, service, exec, user, type);
+}
+
+static int parse_dbus_fragments(void) {
+        _cleanup_closedir_ DIR *d = NULL;
+        struct dirent *de;
+        const char *p, *type;
+        int r;
+
+        r = cg_pid_get_owner_uid(0, NULL);
+        if (r >= 0) {
+                p = "/usr/share/dbus-1/services";
+                type = "session";
+        } else if (r == -ENOENT) {
+                p = "/usr/share/dbus-1/system-services";
+                type = "systemd";
+        } else if (r < 0) {
+                log_error("Failed to determine whether we are running as user or system instance: %s", strerror(-r));
+                return r;
+        }
+
+        d = opendir(p);
+        if (!d) {
+                if (errno == -ENOENT)
+                        return 0;
+
+                log_error("Failed to enumerate D-Bus activated services: %m");
+                return -errno;
+        }
+
+        r = 0;
+        FOREACH_DIRENT(de, d, goto fail) {
+                int q;
+
+                if (!endswith(de->d_name, ".service"))
+                        continue;
+
+                q = add_dbus(p, de->d_name, type);
+                if (q < 0)
+                        r = q;
+        }
+
+        return r;
+
+fail:
+        log_error("Failed to read D-Bus services directory: %m");
+        return -errno;
+}
+
+int main(int argc, char *argv[]) {
+        int r;
+
+        if (argc > 1 && argc != 4) {
+                log_error("This program takes three or no arguments.");
+                return EXIT_FAILURE;
+        }
+
+        if (argc > 1)
+                arg_dest = argv[3];
+
+        log_set_target(LOG_TARGET_SAFE);
+        log_parse_environment();
+        log_open();
+
+        umask(0022);
+
+        if (access("/dev/kdbus/control", F_OK) < 0)
+                return 0;
+
+        r = parse_dbus_fragments();
+
+        return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
+}