src/interfaces/hostnamed/hostnamed.c

   1 /*
   2  * Copyright (c) 2014 Ian Sutton <ian@kremlin.cc>
   3  *
   4  * Permission to use, copy, modify, and distribute this software for any
   5  * purpose with or without fee is hereby granted, provided that the above
   6  * copyright notice and this permission notice appear in all copies.
   7  *
   8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  15  */
  16
  17 #include <unistd.h>
  18 #include <limits.h>
  19 #include <signal.h>
  20
  21 #include <sys/param.h>
  22 #include <string.h>
  23
  24 #include <glib/gprintf.h>
  25 #include <glib-unix.h>
  26
  27 #include "hostnamed-gen.h"
  28 #include "hostnamed.h"
  29
  30 GPtrArray *hostnamed_freeable;
  31 Hostname1 *hostnamed_interf;
  32
  33 GMainLoop *hostnamed_loop;
  34
  35 guint bus_descriptor;
  36 gboolean dbus_interface_exported; /* reliable because of gdbus operational guarantees */
  37
  38 /* --- begin method/property/dbus signal code --- */
  39
  40 static gboolean
  41 on_handle_set_hostname(Hostname1 *hn1_passed_interf,
  42                        GDBusMethodInvocation *invoc,
  43                        const gchar *greet,
  44                        gpointer data) {
  45     return FALSE;
  46 }
  47
  48 static gboolean
  49 on_handle_set_static_hostname(Hostname1 *hn1_passed_interf,
  50                               GDBusMethodInvocation *invoc,
  51                               const gchar *greet,
  52                               gpointer data) {
  53     return FALSE;
  54 }
  55
  56 static gboolean
  57 on_handle_set_pretty_hostname(Hostname1 *hn1_passed_interf,
  58                               GDBusMethodInvocation *invoc,
  59                               const gchar *greet,
  60                               gpointer data) {
  61     return FALSE;
  62 }
  63
  64 static gboolean
  65 on_handle_set_chassis(Hostname1 *hn1_passed_interf,
  66                       GDBusMethodInvocation *invoc,
  67                       const gchar *greet,
  68                       gpointer data) {
  69     return FALSE;
  70 }
  71
  72 static gboolean
  73 on_handle_set_icon_name(Hostname1 *hn1_passed_interf,
  74                         GDBusMethodInvocation *invoc,
  75                         const gchar *greet,
  76                         gpointer data) {
  77     return FALSE;
  78 }
  79
  80 /* note: all hostnamed/hostname1's properties are read-only,
  81  * and do not need set_ functions, gdbus-codegen realized
  82  * this from the XML and handled the to-be error of trying
  83  * to set a read-only property's value
  84  */
  85
  86 const gchar *
  87 our_get_hostname() {
  88
  89     gchar *hostname_buf, *ret;
  90     size_t hostname_divider;
  91
  92     hostname_buf = (gchar*) g_malloc0(MAXHOSTNAMELEN);
  93     ret          = (gchar*) g_malloc0(MAXHOSTNAMELEN);
  94
  95     g_ptr_array_add(hostnamed_freeable, hostname_buf);
  96     g_ptr_array_add(hostnamed_freeable, ret);
  97
  98     if(gethostname(hostname_buf, MAXHOSTNAMELEN) || g_strcmp0(hostname_buf, "") == 0)
  99         return "localhost";
 100
 101     hostname_divider = strcspn(hostname_buf, ".");
 102
 103     return strncpy(ret, hostname_buf, hostname_divider);
 104 }
 105
 106 const gchar *
 107 our_get_static_hostname() {
 108
 109     const gchar *pretty_hostname;
 110     const gchar *ret;
 111
 112     pretty_hostname = our_get_pretty_hostname();
 113
 114     if(g_strcmp0(pretty_hostname, "") == 0)
 115         ret = our_get_hostname();
 116
 117     else if((ret = g_hostname_to_ascii(pretty_hostname))) {
 118
 119         g_ptr_array_add(hostnamed_freeable, (gpointer)ret);
 120         return ret;
 121     }
 122
 123     return ret;
 124 }
 125
 126 const gchar *
 127 our_get_pretty_hostname() {
 128
 129     GKeyFile *config;
 130     gchar *ret;
 131
 132     if(g_key_file_load_from_file(config, "/etc/systemd_compat.conf", G_KEY_FILE_NONE, NULL)
 133         && (ret = g_key_file_get_value(config, "hostnamed", "PrettyHostname", NULL))) { /* ret might need to be freed, docs dont specify but i am suspicious */
 134
 135         g_free(config);
 136         return ret;
 137     }
 138
 139     if(config)
 140         g_free(config);
 141
 142     return "";
 143 }
 144
 145 const gchar *
 146 our_get_chassis() {
 147
 148     return "TODO";
 149 }
 150
 151 const gchar *
 152 our_get_icon_name() {
 153
 154     return "TODO";
 155 }
 156
 157 const gchar *
 158 our_get_kernel_name() {
 159
 160     return "TODO";
 161 }
 162
 163 const gchar *
 164 our_get_kernel_version() {
 165
 166     return "TODO";
 167 }
 168
 169 const gchar *
 170 our_get_kernel_release() {
 171
 172     return "TODO";
 173 }
 174
 175 const gchar *
 176 our_get_os_cpename() {
 177
 178     return "TODO";
 179 }
 180
 181 const gchar *
 182 our_get_os_pretty_name() {
 183
 184     return "TODO";
 185 }
 186
 187 /* --- end method/property/dbus signal code, begin bus/name handlers --- */
 188
 189 static void hostnamed_on_bus_acquired(GDBusConnection *conn,
 190                             const gchar *name,
 191                             gpointer user_data) {
 192
 193     g_printf("got bus/name, exporting %s's interface...\n", name);
 194
 195     hostnamed_interf = hostname1_skeleton_new();
 196
 197     /* attach function pointers to generated struct's method handlers */
 198     g_signal_connect(hostnamed_interf, "handle-set-hostname", G_CALLBACK(on_handle_set_hostname), NULL);
 199     g_signal_connect(hostnamed_interf, "handle-set-static-hostname", G_CALLBACK(on_handle_set_static_hostname), NULL);
 200     g_signal_connect(hostnamed_interf, "handle-set-pretty-hostname", G_CALLBACK(on_handle_set_pretty_hostname), NULL);
 201     g_signal_connect(hostnamed_interf, "handle-set-chassis", G_CALLBACK(on_handle_set_chassis), NULL);
 202     g_signal_connect(hostnamed_interf, "handle-set-icon-name", G_CALLBACK(on_handle_set_icon_name), NULL);
 203
 204     /* set our properties before export */
 205     hostname1_set_hostname(hostnamed_interf, our_get_hostname());
 206     hostname1_set_static_hostname(hostnamed_interf, our_get_static_hostname());
 207     hostname1_set_pretty_hostname(hostnamed_interf, our_get_pretty_hostname());
 208     hostname1_set_chassis(hostnamed_interf, our_get_chassis());
 209     hostname1_set_icon_name(hostnamed_interf, our_get_icon_name());
 210     hostname1_set_kernel_name(hostnamed_interf, our_get_kernel_name());
 211     hostname1_set_kernel_version(hostnamed_interf, our_get_kernel_version());
 212     hostname1_set_kernel_release(hostnamed_interf, our_get_kernel_release());
 213     hostname1_set_operating_system_cpename(hostnamed_interf, our_get_os_cpename());
 214     hostname1_set_operating_system_pretty_name(hostnamed_interf, our_get_os_pretty_name());
 215
 216     if(!g_dbus_interface_skeleton_export(G_DBUS_INTERFACE_SKELETON(hostnamed_interf),
 217                                          conn,
 218                                          "/org/freedesktop/hostname1",
 219                                          NULL)) {
 220
 221         g_printf("failed to export %s's interface!\n", name); /* unusual edge case, TODO check errno */
 222         hostnamed_mem_clean();
 223
 224     } else {
 225
 226         dbus_interface_exported = TRUE;
 227         g_printf("exported %s's interface on the system bus...\n", name);
 228     }
 229 }
 230
 231 static void hostnamed_on_name_acquired(GDBusConnection *conn,
 232                                        const gchar *name,
 233                                        gpointer user_data) {
 234
 235     g_printf("success!\n");
 236 }
 237
 238 static void hostnamed_on_name_lost(GDBusConnection *conn,
 239                                    const gchar *name,
 240                                    gpointer user_data) {
 241
 242     if(!conn) {
 243
 244         g_printf("failed to connect to the system bus while trying to acquire name '%s': either dbus-daemon isn't running or we don't have permission to push names and/or their interfaces to it.\n", name);
 245         hostnamed_mem_clean();
 246     }
 247
 248     g_printf("lost name %s, exiting...\n", name);
 249
 250     hostnamed_mem_clean();
 251 }
 252
 253 /* --- end bus/name handlers, begin misc unix functions --- */
 254
 255 /* safe call to clean and then exit
 256  * this stops our GMainLoop safely before letting main() return */
 257 void hostnamed_mem_clean() {
 258
 259     g_printf("exiting...\n");
 260
 261     if(dbus_interface_exported)
 262         g_dbus_interface_skeleton_unexport(G_DBUS_INTERFACE_SKELETON(hostnamed_interf));
 263
 264     if(g_main_loop_is_running(hostnamed_loop))
 265         g_main_loop_quit(hostnamed_loop);
 266
 267 }
 268
 269 /* wrapper for glib's unix signal handling; called only once if terminatating signal is raised against us */
 270 gboolean unix_sig_terminate_handler(gpointer data) {
 271
 272     g_printf("caught SIGINT/HUP/TERM, exiting\n");
 273
 274     hostnamed_mem_clean();
 275     return G_SOURCE_REMOVE;
 276 }
 277
 278 void set_signal_handlers() {
 279
 280     /* we don't care about its descriptor, we never need to unregister these */
 281     g_unix_signal_add(SIGINT,  unix_sig_terminate_handler, NULL);
 282     g_unix_signal_add(SIGHUP,  unix_sig_terminate_handler, NULL);
 283     g_unix_signal_add(SIGTERM, unix_sig_terminate_handler, NULL);
 284
 285     /* TODO: the "only once" guarantee only counts towards specific signals.
 286      *       make sure calling a SIGINT and SIGHUP doesn't cause term_handler()
 287      *       to be called twice */
 288 }
 289
 290 int main() {
 291
 292     set_signal_handlers();
 293
 294     hostnamed_loop = g_main_loop_new(NULL, TRUE);
 295     hostnamed_freeable = g_ptr_array_new();
 296
 297     bus_descriptor = g_bus_own_name(G_BUS_TYPE_SYSTEM,
 298                                    "org.freedesktop.hostname1",
 299                                    G_BUS_NAME_OWNER_FLAGS_NONE,
 300                                    hostnamed_on_bus_acquired,
 301                                    hostnamed_on_name_acquired,
 302                                    hostnamed_on_name_lost,
 303                                    NULL,
 304                                    NULL);
 305
 306     g_main_loop_run(hostnamed_loop);
 307     /* runs until single g_main_loop_quit() call is raised inside <interface>_mem_clean() */
 308     g_main_loop_unref(hostnamed_loop);
 309
 310     /* guaranteed unownable */
 311     g_bus_unown_name(bus_descriptor);
 312
 313     /* at this point no operations can occur with our data, it is safe to free it + its container */
 314     g_ptr_array_free(hostnamed_freeable, TRUE);
 315
 316     return 0;
 317 }
 318
 319 /* TODO figure out DMI variables on obsd */
 320 /*static gchar *guess_icon_name() {
 321
 322     gchar *filebuf = NULL;
 323     gchar *ret = NULL;
 324
 325     #if defined(__i386__) || defined(__x86_64__)
 326
 327        Taken with a few minor changes from systemd's hostnamed.c,
 328        copyright 2011 Lennart Poettering.
 329
 330        See the SMBIOS Specification 2.7.1 section 7.4.1 for
 331        details about the values listed here:
 332
 333        http://www.dmtf.org/sites/default/files/standards/documents/DSP0134_2.7.1.pdf
 334
 335
 336     if (g_file_get_contents ("/sys/class/dmi/id/chassis_type", &filebuf, NULL, NULL)) {
 337         switch (g_ascii_strtoull (filebuf, NULL, 10)) {
 338         case 0x3:
 339         case 0x4:
 340         case 0x5:
 341         case 0x6:
 342         case 0x7:
 343             ret = g_strdup ("computer-desktop");
 344             goto out;
 345         case 0x9:
 346         case 0xA:
 347         case 0xE:
 348             ret = g_strdup ("computer-laptop");
 349             goto out;
 350         case 0x11:
 351         case 0x17:
 352         case 0x1C:
 353         case 0x1D:
 354             ret = g_strdup ("computer-server");
 355             goto out;
 356         }
 357     }
 358     #endif
 359     ret = g_strdup ("computer");
 360   out:
 361     g_free (filebuf);
 362     return ret;
 363 }*/
 364