lookup.subproj/muser_module.c

   1 /*
   2  * Copyright (c) 2015 Apple Inc.  All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This ds contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this ds except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * ds.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23
  24 #ifdef MUSER_AVAILABLE
  25
  26 #include <dispatch/dispatch.h>
  27 #include <libinfo_muser.h>
  28 #include <mach/mach_host.h>
  29 #include <machine/cpu_capabilities.h>
  30 #include <si_data.h>
  31 #include <si_module.h>
  32 #include <stdio.h>
  33 #include <xpc/xpc.h>
  34 #include <xpc/private.h>
  35
  36 static int _si_muser_disabled = 0;
  37 static xpc_pipe_t __muser_pipe;
  38 static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
  39
  40 XPC_RETURNS_RETAINED
  41 static xpc_pipe_t _muser_xpc_pipe(bool reset);
  42
  43 XPC_RETURNS_RETAINED
  44 static xpc_object_t
  45 _muser_call(const char *procname, xpc_object_t payload)
  46 {
  47         xpc_object_t result = NULL;
  48         xpc_object_t reply;
  49         xpc_pipe_t pipe;
  50
  51         if (!payload) { return NULL; }
  52
  53         pipe = _muser_xpc_pipe(false);
  54         if (!pipe) { return NULL; }
  55
  56         xpc_dictionary_set_string(payload, kLIMMessageRPCName, procname);
  57         xpc_dictionary_set_uint64(payload, kLIMMessageVersion, 1);
  58
  59         int rv = xpc_pipe_routine(pipe, payload, &reply);
  60         switch (rv) {
  61                 case 0:
  62                         result = reply;
  63                         break;
  64                 case EAGAIN:
  65                 case EPIPE:
  66                 default:
  67                         break;
  68         }
  69
  70         xpc_release(pipe);
  71         return result;
  72 }
  73
  74 static int
  75 _muser_xpc_pipe_disabled(xpc_pipe_t pipe)
  76 {
  77         xpc_object_t dict, reply = NULL;
  78         int disabled = 0;
  79
  80         if (pipe == NULL) { return 1; }
  81
  82         dict = xpc_dictionary_create(NULL, NULL, 0);
  83         xpc_dictionary_set_string(dict, kLIMMessageReqtype, kLIMMessageReplyAvailable);
  84         xpc_dictionary_set_int64(dict, kLIMMessageVersion, 1);
  85
  86         int rv = xpc_pipe_routine(pipe, dict, &reply);
  87         switch (rv) {
  88         case 0:
  89                 disabled = !xpc_dictionary_get_bool(reply, kLIMMessageReplyAvailable);
  90                 xpc_release(reply);
  91                 break;
  92         case EPIPE:
  93         case EAGAIN:
  94         default:
  95                 disabled = 1;
  96                 break;
  97         }
  98
  99         xpc_release(dict);
 100         return disabled;
 101 }
 102
 103 XPC_RETURNS_RETAINED
 104 static xpc_pipe_t
 105 _muser_xpc_pipe(bool reset)
 106 {
 107         static dispatch_once_t once;
 108         xpc_pipe_t pipe = NULL;
 109
 110         dispatch_once(&once, ^{
 111                 char *xbs_disable;
 112                 kern_return_t rv;
 113                 uint32_t multiuser_flags = 0;
 114
 115                 /* mirrors the ds_module build environment override */
 116                 xbs_disable = getenv("XBS_DISABLE_LIBINFO");
 117                 if ((issetugid() == 0) && (xbs_disable != NULL) && (strcmp(xbs_disable, "YES") == 0)) {
 118                         _si_muser_disabled = 1;
 119                         return;
 120                 }
 121
 122                 /* check the xnu commpage bit to see if we're multiuser */
 123                 rv = host_get_multiuser_config_flags(mach_host_self(), &multiuser_flags);
 124                 if (rv == KERN_SUCCESS && (multiuser_flags & kIsMultiUserDevice) == 0) {
 125                         _si_muser_disabled = 1;
 126                         return;
 127                 }
 128         });
 129
 130         if (_si_muser_disabled == 1) {
 131                 return NULL;
 132         }
 133
 134         pthread_mutex_lock(&mutex);
 135         if (reset) {
 136                 xpc_release(__muser_pipe);
 137                 __muser_pipe = NULL;
 138         }
 139
 140         if (__muser_pipe == NULL) {
 141                 __muser_pipe = xpc_pipe_create(kLibinfoMultiuserPortName, 0);
 142                 if (!_si_muser_disabled) { _si_muser_disabled = _muser_xpc_pipe_disabled(__muser_pipe); }
 143         }
 144
 145         if (__muser_pipe) { pipe = xpc_retain(__muser_pipe); }
 146         pthread_mutex_unlock(&mutex);
 147
 148         return pipe;
 149 }
 150
 151 static bool
 152 _muser_available(void)
 153 {
 154         xpc_pipe_t pipe;
 155
 156         pipe = _muser_xpc_pipe(false);
 157         if (pipe != NULL) {
 158                 xpc_release(pipe);
 159         }
 160
 161         if (_si_muser_disabled) {
 162                 return 0;
 163         }
 164
 165         return (pipe != NULL);
 166 }
 167
 168 static si_item_t *
 169 _muser_extract_user(si_mod_t *si, xpc_object_t reply, uint64_t valid_global, uint64_t valid_cat) {
 170         __block struct passwd p;
 171         __block int reqs = 3;
 172         p.pw_name = (char *)"";
 173         p.pw_passwd = (char *)"*";
 174         p.pw_uid = (uid_t)0;
 175         p.pw_gid = (gid_t)0;
 176         p.pw_change = (time_t)0;
 177         p.pw_expire = (time_t)0;
 178         p.pw_class = (char *)"";
 179         p.pw_gecos = (char *)"";
 180         p.pw_dir = (char *)"/var/empty";
 181         p.pw_shell = (char *)"/usr/bin/false";
 182
 183         xpc_dictionary_apply(reply, ^bool(const char *key, xpc_object_t value) {
 184                 if (key == NULL) { return true; }
 185                 else if (!strcmp(key, kLIMMessageReplyName)) {
 186                         const char *nm = xpc_string_get_string_ptr(value);
 187                         if (nm) {
 188                                 p.pw_name = (char *)nm;
 189                                 reqs--;
 190                         }
 191                 }
 192                 else if (!strcmp(key, kLIMMessageReplyPasswd)) {
 193                         const char *pw = xpc_string_get_string_ptr(value);
 194                         if (pw) { p.pw_passwd = (char *)pw; }
 195                 }
 196                 else if (!strcmp(key, kLIMMessageReplyUID)) {
 197                         if (xpc_get_type(value) == XPC_TYPE_INT64) {
 198                                 int64_t uid = xpc_int64_get_value(value);
 199                                 p.pw_uid = uid;
 200                                 reqs--;
 201                         }
 202                 }
 203                 else if (!strcmp(key, kLIMMessageReplyGID)) {
 204                         if (xpc_get_type(value) == XPC_TYPE_INT64) {
 205                                 p.pw_gid = xpc_int64_get_value(value);
 206                                 reqs--;
 207                         }
 208                 }
 209                 else if (!strcmp(key, kLIMMessageReplyHome)) {
 210                         const char *home = xpc_string_get_string_ptr(value);
 211                         if (home) { p.pw_dir = (char *)home; };
 212                 }
 213                 else if (!strcmp(key, kLIMMessageReplyShell)) {
 214                         const char *shell = xpc_string_get_string_ptr(value);
 215                         if (shell) { p.pw_shell = (char *)shell; }
 216                 }
 217                 return true;
 218         });
 219
 220         if (reqs != 0) { return NULL; }
 221
 222         return (si_item_t *)LI_ils_create("L4488ss44LssssL", (unsigned long)si, CATEGORY_USER, 1, valid_global, valid_cat, p.pw_name, p.pw_passwd, p.pw_uid, p.pw_gid, p.pw_change, p.pw_class, p.pw_gecos, p.pw_dir, p.pw_shell, p.pw_expire);
 223 }
 224
 225 static si_item_t *
 226 _muser_extract_group(si_mod_t *si, xpc_object_t reply, uint64_t vg, uint64_t vc)
 227 {
 228         __block struct group g;
 229         __block int reqs = 2;
 230         g.gr_gid = (gid_t)0;
 231         g.gr_name = (char *)"";
 232         g.gr_passwd = (char *)"*";
 233         g.gr_mem = NULL;
 234
 235         xpc_dictionary_apply(reply, ^bool(const char *key, xpc_object_t value) {
 236                 if (key == NULL) { return true; }
 237                 else if (!strcmp(key, kLIMMessageReplyGroupname)) {
 238                         const char *nm = xpc_string_get_string_ptr(value);
 239                         if (nm) {
 240                                 g.gr_name = (char *)nm;
 241                                 reqs--;
 242                         }
 243                 }
 244                 else if (!strcmp(key, kLIMMessageReplyGroupID)) {
 245                         if (xpc_get_type(value) == XPC_TYPE_INT64) {
 246                                 g.gr_gid = xpc_int64_get_value(value);
 247                                 reqs--;
 248                         }
 249                 }
 250                 else if (!strcmp(key, kLIMMessageReplyGroupMembers)) {
 251                         if (xpc_get_type(value) == XPC_TYPE_ARRAY) {
 252                                 size_t count = xpc_array_get_count(value);
 253                                 g.gr_mem = (char **)malloc(sizeof(char *) * (count + 1));
 254                                 g.gr_mem[count] = NULL;
 255
 256                                 for (size_t i=0; i<count; i++) {
 257                                         g.gr_mem[i] = (char *)xpc_array_get_string(value, i);
 258                                 }
 259                         }
 260                 }
 261                 return true;
 262         });
 263
 264         if (reqs != 0) { return NULL; }
 265
 266         si_item_t *item = (si_item_t *)LI_ils_create("L4488ss4*", (unsigned long)si, CATEGORY_GROUP, 1,
 267                         vg, vc, g.gr_name, g.gr_passwd, g.gr_gid, g.gr_mem);
 268
 269         free(g.gr_mem);
 270         return item;
 271 }
 272
 273 static si_item_t *
 274 _muser_extract_grouplist(si_mod_t *si, xpc_object_t reply, const char *user,
 275                 uint64_t vg, uint64_t vc)
 276 {
 277         gid_t __block *gidlist = NULL;
 278         size_t gidcount = 0;
 279         si_item_t *item = NULL;
 280
 281         if (user == NULL) { return NULL; }
 282
 283         xpc_object_t list = xpc_dictionary_get_value(reply, kLIMMessageReplyGrouplist);
 284         if (list) {
 285                 if (xpc_get_type(list) == XPC_TYPE_ARRAY) {
 286                         gidcount = xpc_array_get_count(list);
 287                         gidlist = (gid_t *)calloc(gidcount + 1, sizeof(gid_t));
 288
 289                         xpc_array_apply(list, ^bool(size_t index, xpc_object_t value) {
 290                                 if (xpc_get_type(value) == XPC_TYPE_INT64) {
 291                                         gidlist[index] = xpc_int64_get_value(value);
 292                                         return true;
 293                                 } else {
 294                                         free(gidlist);
 295                                         gidlist = NULL;
 296                                         return false;
 297                                 }
 298                         });
 299                 }
 300         }
 301
 302         if (gidlist) {
 303                 item = (si_item_t *)LI_ils_create("L4488s4@", (unsigned long)si, CATEGORY_GROUPLIST,
 304                                 1, vg, vc, user, gidcount, gidcount * sizeof(gid_t), gidlist);
 305         }
 306
 307         free(gidlist);
 308         return item;
 309 }
 310
 311 #pragma mark -
 312
 313 static si_item_t *
 314 muser_user_byname(si_mod_t *si, const char *name)
 315 {
 316         xpc_object_t payload;
 317         si_item_t *item = NULL;
 318
 319         if (!_muser_available()) { return NULL; }
 320
 321         payload = xpc_dictionary_create(NULL, NULL, 0);
 322         if (!payload) { return NULL; }
 323
 324         xpc_dictionary_set_string(payload, kLIMMessageReqtype, kLIMMessageRequestUsername);
 325         xpc_dictionary_set_string(payload, kLIMMessageQuery, name);
 326
 327         xpc_object_t reply = _muser_call("getpwnam", payload);
 328         if (reply) {
 329                 item = _muser_extract_user(si, reply, 0, 0);
 330                 xpc_release(reply);
 331         }
 332
 333         xpc_release(payload);
 334         return item;
 335 }
 336
 337 static si_item_t *
 338 muser_user_byuid(si_mod_t *si, uid_t uid)
 339 {
 340         xpc_object_t payload;
 341         si_item_t *item = NULL;
 342
 343         if (!_muser_available()) { return NULL; }
 344
 345         payload = xpc_dictionary_create(NULL, NULL, 0);
 346         if (!payload) { return NULL; }
 347
 348         xpc_dictionary_set_string(payload, kLIMMessageReqtype, kLIMMessageRequestUID);
 349         xpc_dictionary_set_int64(payload, kLIMMessageQuery, uid);
 350
 351         xpc_object_t reply = _muser_call("getpwuid", payload);
 352         if (reply) {
 353                 item = _muser_extract_user(si, reply, 0, 0);
 354                 xpc_release(reply);
 355         }
 356
 357         xpc_release(payload);
 358         return item;
 359 }
 360
 361 static si_item_t *
 362 muser_group_byname(struct si_mod_s *si, const char *name)
 363 {
 364         xpc_object_t payload;
 365         si_item_t *item = NULL;
 366
 367         if (!_muser_available()) { return NULL; }
 368
 369         payload = xpc_dictionary_create(NULL, NULL, 0);
 370         if (!payload) { return NULL; }
 371
 372         xpc_dictionary_set_string(payload, kLIMMessageReqtype, kLIMMessageRequestGroupname);
 373         xpc_dictionary_set_string(payload, kLIMMessageQuery, name);
 374
 375         xpc_object_t reply = _muser_call("getgrnam", payload);
 376         if (reply) {
 377                 item = _muser_extract_group(si, reply, 0, 0);
 378                 xpc_release(reply);
 379         }
 380
 381         xpc_release(payload);
 382         return item;
 383 }
 384
 385 static si_item_t *
 386 muser_group_bygid(struct si_mod_s *si, gid_t gid)
 387 {
 388         xpc_object_t payload;
 389         si_item_t *item = NULL;
 390
 391         if (!_muser_available()) { return NULL; }
 392
 393         payload = xpc_dictionary_create(NULL, NULL, 0);
 394         if (!payload) { return NULL; }
 395
 396         xpc_dictionary_set_string(payload, kLIMMessageReqtype, kLIMMessageRequestGID);
 397         xpc_dictionary_set_int64(payload, kLIMMessageQuery, gid);
 398
 399         xpc_object_t reply = _muser_call("getgrgid", payload);
 400         if (reply) {
 401                 item = _muser_extract_group(si, reply, 0, 0);
 402                 xpc_release(reply);
 403         }
 404
 405         xpc_release(payload);
 406         return item;
 407 }
 408
 409 static si_item_t *
 410 muser_grouplist(struct si_mod_s *si, const char *name, uint32_t count)
 411 {
 412         xpc_object_t payload;
 413         si_item_t *item = NULL;
 414
 415         if (!_muser_available()) { return NULL; }
 416
 417         payload = xpc_dictionary_create(NULL, NULL, 0);
 418         if (!payload) { return NULL; }
 419
 420         xpc_dictionary_set_string(payload, kLIMMessageReqtype, kLIMMessageRequestGrouplist);
 421         xpc_dictionary_set_string(payload, kLIMMessageQuery, name);
 422
 423         xpc_object_t reply = _muser_call("getgrouplist", payload);
 424         if (reply) {
 425                 item = _muser_extract_grouplist(si, reply, name, 0, 0);
 426                 xpc_release(reply);
 427         }
 428
 429         xpc_release(payload);
 430         return item;
 431 }
 432
 433 #pragma mark -
 434
 435 si_mod_t *
 436 si_module_static_muser(void)
 437 {
 438         static const struct si_mod_vtable_s muser_vtable =
 439         {
 440                 .sim_user_byname = &muser_user_byname,
 441                 .sim_user_byuid = &muser_user_byuid,
 442
 443                 .sim_group_byname = &muser_group_byname,
 444                 .sim_group_bygid = &muser_group_bygid,
 445                 .sim_grouplist = &muser_grouplist,
 446         };
 447
 448         static si_mod_t si =
 449         {
 450                 .vers = 1,
 451                 .refcount = 1,
 452                 .flags = SI_MOD_FLAG_STATIC,
 453
 454                 .private = NULL,
 455                 .vtable = &muser_vtable,
 456         };
 457
 458         static dispatch_once_t once;
 459         dispatch_once(&once, ^{
 460                 si.name = strdup("muser");
 461         });
 462
 463         return &si;
 464 }
 465
 466 #endif // MUSER_AVAILABLE