Security/authd/authtoken.c

   1 /* Copyright (c) 2012-2013 Apple Inc. All Rights Reserved. */
   2
   3 #include "authtoken.h"
   4 #include "authd_private.h"
   5 #include "process.h"
   6 #include "authitems.h"
   7 #include "debugging.h"
   8 #include "authutilities.h"
   9 #include "server.h"
  10
  11 #include <CommonCrypto/CommonRandomSPI.h>
  12 #include <Security/Authorization.h>
  13 #include <Security/SecBase.h>
  14 #include <sandbox.h>
  15
  16 static Boolean AuthTokenEqualCallBack(const void *value1, const void *value2)
  17 {
  18     return (*(uint64_t*)value1) == (*(uint64_t*)value2);
  19 }
  20
  21 static CFHashCode AuthTokenHashCallBack(const void *value)
  22 {
  23 //    CFHashCode hash;
  24 //    AuthorizationBlob* blob = (AuthorizationBlob*)value;
  25 //    hash = blob->data[1];
  26 //    hash <<= 32;
  27 //    hash |= blob->data[0];
  28 //    return hash;
  29     //quick 64 bit aligned version
  30     return *((CFHashCode*)((AuthorizationBlob*)value)->data);
  31 }
  32
  33 const CFDictionaryKeyCallBacks kAuthTokenKeyCallBacks = {
  34     .version = 0,
  35     .retain = NULL,
  36     .release = NULL,
  37     .copyDescription = NULL,
  38     .equal = &AuthTokenEqualCallBack,
  39     .hash = &AuthTokenHashCallBack
  40 };
  41
  42 struct _auth_token_s {
  43     __AUTH_BASE_STRUCT_HEADER__;
  44
  45     AuthorizationBlob blob;
  46     auth_token_state_t state;
  47     audit_info_s auditInfo;
  48     dispatch_queue_t dispatch_queue;
  49
  50     CFMutableSetRef processes;
  51
  52     session_t session;
  53     process_t creator; // weak reference, used for entitlement checking
  54     mach_port_t creator_bootstrap_port;
  55
  56     auth_items_t context;
  57
  58     CFMutableSetRef credentials;
  59     CFMutableSetRef authorized_rights;
  60
  61     bool least_privileged;
  62     bool appleSigned;
  63
  64     bool sandboxed;
  65     char * code_url;
  66
  67     credential_t credential;
  68 };
  69
  70 static void
  71 _auth_token_finalize(CFTypeRef value)
  72 {
  73     auth_token_t auth = (auth_token_t)value;
  74     LOGV("authtoken: deallocated %p", auth);
  75
  76     dispatch_barrier_sync(auth->dispatch_queue, ^{});
  77
  78     dispatch_release(auth->dispatch_queue);
  79     CFReleaseSafe(auth->session);
  80     CFReleaseSafe(auth->processes);
  81     CFReleaseSafe(auth->context);
  82     CFReleaseSafe(auth->credentials);
  83     CFReleaseSafe(auth->authorized_rights);
  84     free_safe(auth->code_url);
  85     CFReleaseSafe(auth->credential);
  86
  87     if (auth->creator_bootstrap_port != MACH_PORT_NULL) {
  88         mach_port_deallocate(mach_task_self(), auth->creator_bootstrap_port);
  89     }
  90 }
  91
  92 static Boolean
  93 _auth_token_equal(CFTypeRef value1, CFTypeRef value2)
  94 {
  95     auth_token_t auth1 = (auth_token_t)value1;
  96     auth_token_t auth2 = (auth_token_t)value2;
  97
  98     return memcmp(&auth1->blob, &auth2->blob, sizeof(AuthorizationBlob)) == 0;
  99 }
 100
 101 static CFStringRef
 102 _auth_token_copy_description(CFTypeRef value)
 103 {
 104     auth_token_t auth = (auth_token_t)value;
 105     return CFStringCreateWithFormat(kCFAllocatorDefault, NULL, CFSTR("auth_token: %p, uid=%i, pid=%i, processes=%li least_privileged=%i"),
 106                                     auth, auth->auditInfo.euid, auth->auditInfo.pid, CFSetGetCount(auth->processes), auth->least_privileged);
 107 }
 108
 109 static CFHashCode
 110 _auth_token_hash(CFTypeRef value)
 111 {
 112     auth_token_t auth = (auth_token_t)value;
 113     return *(CFHashCode*)&auth->blob;
 114 }
 115
 116 AUTH_TYPE_INSTANCE(auth_token,
 117                    .init = NULL,
 118                    .copy = NULL,
 119                    .finalize = _auth_token_finalize,
 120                    .equal = _auth_token_equal,
 121                    .hash = _auth_token_hash,
 122                    .copyFormattingDesc = NULL,
 123                    .copyDebugDesc = _auth_token_copy_description
 124                    );
 125
 126 static CFTypeID auth_token_get_type_id() {
 127     static CFTypeID type_id = _kCFRuntimeNotATypeID;
 128     static dispatch_once_t onceToken;
 129
 130     dispatch_once(&onceToken, ^{
 131         type_id = _CFRuntimeRegisterClass(&_auth_type_auth_token);
 132     });
 133
 134     return type_id;
 135 }
 136
 137 static auth_token_t
 138 _auth_token_create(const audit_info_s * auditInfo, bool operateAsLeastPrivileged)
 139 {
 140 #if __LLP64__
 141     __Check_Compile_Time(sizeof(CFHashCode) == sizeof(AuthorizationBlob));
 142 #endif
 143
 144     auth_token_t auth = (auth_token_t)_CFRuntimeCreateInstance(kCFAllocatorDefault, auth_token_get_type_id(), AUTH_CLASS_SIZE(auth_token), NULL);
 145     require(auth != NULL, done);
 146
 147     if (CCRandomCopyBytes(kCCRandomDefault, auth->blob.data, sizeof(auth->blob.data)) != kCCSuccess) {
 148         LOGE("authtoken[%i]: failed to generate blob", auditInfo->pid);
 149         CFReleaseNull(auth);
 150         goto done;
 151     }
 152
 153     auth->context = auth_items_create();
 154     auth->auditInfo = *auditInfo;
 155     auth->least_privileged = operateAsLeastPrivileged;
 156
 157     auth->dispatch_queue = dispatch_queue_create(NULL, DISPATCH_QUEUE_SERIAL);
 158     check(auth->dispatch_queue != NULL);
 159
 160     auth->credentials = CFSetCreateMutable(kCFAllocatorDefault, 0, &kCFTypeSetCallBacks);
 161     auth->authorized_rights = CFSetCreateMutable(kCFAllocatorDefault, 0, &kCFTypeSetCallBacks);
 162     auth->processes = CFSetCreateMutable(kCFAllocatorDefault, 0, NULL);
 163     auth->creator_bootstrap_port = MACH_PORT_NULL;
 164
 165     if (sandbox_check(auth->auditInfo.pid, "authorization-right-obtain", SANDBOX_CHECK_NO_REPORT) != 0)
 166                 auth->sandboxed = true;
 167         else
 168                 auth->sandboxed = false;
 169
 170 #if DEBUG
 171     CFHashCode code = AuthTokenHashCallBack(&auth->blob);
 172     if (memcmp(&code, auth->blob.data, sizeof(auth->blob.data)) != 0) {
 173         LOGD("authtoken[%i]: blob = %x%01x", auth->auditInfo.pid, auth->blob.data[1], auth->blob.data[0]);
 174         LOGD("authtoken[%i]: hash = %lx", auth->auditInfo.pid, code);
 175         assert(false);
 176     }
 177 #endif
 178
 179 done:
 180     return auth;
 181 }
 182
 183 auth_token_t
 184 auth_token_create(process_t proc, bool operateAsLeastPrivileged)
 185 {
 186     auth_token_t auth = NULL;
 187     require(proc != NULL, done);
 188
 189     auth = _auth_token_create(process_get_audit_info(proc), operateAsLeastPrivileged);
 190     require(auth != NULL, done);
 191
 192     auth->creator = proc;
 193     auth->session = (session_t)CFRetain(process_get_session(proc));
 194     auth->code_url = _copy_string(process_get_code_url(proc));
 195     auth->appleSigned = process_apple_signed(proc);
 196     auth->creator_bootstrap_port = process_get_bootstrap(proc);
 197     // This line grabs a reference to the send right to the bootstrap (our right to send to the bootstrap)
 198     // This makes it critical to use the same call in reverse as we are only getting a ref to one right,
 199     // but deallocate will free a ref to all 5 rights.
 200     if (auth->creator_bootstrap_port != MACH_PORT_NULL) {
 201         kern_return_t error_code = mach_port_mod_refs(mach_task_self(), auth->creator_bootstrap_port, MACH_PORT_RIGHT_SEND, 1);
 202         if (error_code != KERN_SUCCESS) {
 203             // If no reference to the mach port right can be obtained, we don't hold the copy, so mark it NULL again!
 204             auth->creator_bootstrap_port = MACH_PORT_NULL;
 205         }
 206     }
 207
 208     LOGV("authtoken[%i]: created %p", auth->auditInfo.pid, auth);
 209
 210 done:
 211     return auth;
 212 }
 213
 214 auth_token_t
 215 auth_token_create_with_audit_info(const audit_info_s* info, bool operateAsLeastPrivileged)
 216 {
 217     OSStatus status = errSecSuccess;
 218     SecCodeRef code_Ref = NULL;
 219     CFURLRef code_url = NULL;
 220
 221     auth_token_t auth = NULL;
 222     require(info != NULL, done);
 223
 224     auth = _auth_token_create(info, operateAsLeastPrivileged);
 225     require(auth != NULL, done);
 226
 227     auth->session = server_find_copy_session(info->asid, true);
 228     if (auth->session == NULL) {
 229         LOGV("authtoken[%i]: failed to create session", auth->auditInfo.pid);
 230         CFReleaseNull(auth);
 231         goto done;
 232     }
 233
 234     CFMutableDictionaryRef codeDict = CFDictionaryCreateMutable(kCFAllocatorDefault, 0, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks);
 235     CFNumberRef codePid = CFNumberCreate(kCFAllocatorDefault, kCFNumberIntType, &auth->auditInfo.pid);
 236     CFDictionarySetValue(codeDict, kSecGuestAttributePid, codePid);
 237     status = SecCodeCopyGuestWithAttributes(NULL, codeDict, kSecCSDefaultFlags, &code_Ref);
 238     CFReleaseSafe(codeDict);
 239     CFReleaseSafe(codePid);
 240
 241     if (status) {
 242         LOGV("authtoken[%i]: failed to create code ref (%i)", auth->auditInfo.pid, status);
 243         CFReleaseNull(auth);
 244         goto done;
 245     }
 246
 247     if (SecCodeCopyPath(code_Ref, kSecCSDefaultFlags, &code_url) == errSecSuccess) {
 248         auth->code_url = calloc(1u, PATH_MAX+1);
 249         if (auth->code_url) {
 250             CFURLGetFileSystemRepresentation(code_url, true, (UInt8*)auth->code_url, PATH_MAX);
 251         }
 252     }
 253
 254     LOGV("authtoken[%i]: created %p for %s", auth->auditInfo.pid, auth, auth->code_url);
 255
 256 done:
 257     CFReleaseSafe(code_Ref);
 258     CFReleaseSafe(code_url);
 259     return auth;
 260 }
 261
 262 bool
 263 auth_token_get_sandboxed(auth_token_t auth)
 264 {
 265     return auth->sandboxed;
 266 }
 267
 268 const char *
 269 auth_token_get_code_url(auth_token_t auth)
 270 {
 271     return auth->code_url;
 272 }
 273
 274 const void *
 275 auth_token_get_key(auth_token_t auth)
 276 {
 277     return &auth->blob;
 278 }
 279
 280 auth_items_t
 281 auth_token_get_context(auth_token_t auth)
 282 {
 283     return auth->context;
 284 }
 285
 286 bool
 287 auth_token_least_privileged(auth_token_t auth)
 288 {
 289     return auth->least_privileged;
 290 }
 291
 292 uid_t
 293 auth_token_get_uid(auth_token_t auth)
 294 {
 295     return auth ? auth->auditInfo.euid : (uid_t)-2;
 296 }
 297
 298 pid_t
 299 auth_token_get_pid(auth_token_t auth)
 300 {
 301     return auth ? auth->auditInfo.pid : -1;
 302 }
 303
 304 session_t
 305 auth_token_get_session(auth_token_t auth)
 306 {
 307     return auth->session;
 308 }
 309
 310 const AuthorizationBlob *
 311 auth_token_get_blob(auth_token_t auth)
 312 {
 313     return &auth->blob;
 314 }
 315
 316 const audit_info_s *
 317 auth_token_get_audit_info(auth_token_t auth)
 318 {
 319     return &auth->auditInfo;
 320 }
 321
 322 mach_port_t
 323 auth_token_get_creator_bootstrap(auth_token_t auth)
 324 {
 325     return auth->creator_bootstrap_port;
 326 }
 327
 328 CFIndex
 329 auth_token_add_process(auth_token_t auth, process_t proc)
 330 {
 331     __block CFIndex count = 0;
 332     dispatch_sync(auth->dispatch_queue, ^{
 333         CFSetAddValue(auth->processes, proc);
 334         count = CFSetGetCount(auth->processes);
 335     });
 336     return count;
 337 }
 338
 339 CFIndex
 340 auth_token_remove_process(auth_token_t auth, process_t proc)
 341 {
 342     __block CFIndex count = 0;
 343     dispatch_sync(auth->dispatch_queue, ^{
 344         if (auth->creator == proc) {
 345             auth->creator = NULL;
 346         }
 347         CFSetRemoveValue(auth->processes, proc);
 348         count = CFSetGetCount(auth->processes);
 349     });
 350     return count;
 351 }
 352
 353 CFIndex
 354 auth_token_get_process_count(auth_token_t auth)
 355 {
 356     __block CFIndex count = 0;
 357     dispatch_sync(auth->dispatch_queue, ^{
 358         count = CFSetGetCount(auth->processes);
 359     });
 360     return count;
 361 }
 362
 363 void
 364 auth_token_set_credential(auth_token_t auth, credential_t cred)
 365 {
 366     dispatch_sync(auth->dispatch_queue, ^{
 367         CFSetSetValue(auth->credentials, cred);
 368     });
 369 }
 370
 371 bool
 372 auth_token_credentials_iterate(auth_token_t auth, credential_iterator_t iter)
 373 {
 374     __block bool result = false;
 375
 376     dispatch_sync(auth->dispatch_queue, ^{
 377         CFIndex count = CFSetGetCount(auth->credentials);
 378         CFTypeRef values[count];
 379         CFSetGetValues(auth->credentials, values);
 380         for (CFIndex i = 0; i < count; i++) {
 381             credential_t cred = (credential_t)values[i];
 382             result = iter(cred);
 383             if (!result) {
 384                 break;
 385             }
 386         }
 387     });
 388
 389     return result;
 390 }
 391
 392 void
 393 auth_token_set_right(auth_token_t auth, credential_t right)
 394 {
 395     dispatch_sync(auth->dispatch_queue, ^{
 396         CFSetSetValue(auth->authorized_rights, right);
 397     });
 398 }
 399
 400 bool
 401 auth_token_rights_iterate(auth_token_t auth, credential_iterator_t iter)
 402 {
 403     __block bool result = false;
 404
 405     dispatch_sync(auth->dispatch_queue, ^{
 406         CFIndex count = CFSetGetCount(auth->authorized_rights);
 407         CFTypeRef values[count];
 408         CFSetGetValues(auth->authorized_rights, values);
 409         for (CFIndex i = 0; i < count; i++) {
 410             credential_t right = (credential_t)values[i];
 411             result = iter(right);
 412             if (!result) {
 413                 break;
 414             }
 415         }
 416     });
 417
 418     return result;
 419 }
 420
 421 CFTypeRef
 422 auth_token_copy_entitlement_value(auth_token_t auth, const char * entitlement)
 423 {
 424     __block CFTypeRef value = NULL;
 425     dispatch_sync(auth->dispatch_queue, ^{
 426         if (auth->creator) {
 427             value = process_copy_entitlement_value(auth->creator, entitlement);
 428         }
 429     });
 430
 431     return value;
 432 }
 433
 434 bool
 435 auth_token_has_entitlement(auth_token_t auth, const char * entitlement)
 436 {
 437     __block bool entitled = false;
 438
 439     dispatch_sync(auth->dispatch_queue, ^{
 440         if (auth->creator) {
 441             entitled = process_has_entitlement(auth->creator, entitlement);
 442         }
 443     });
 444
 445     return entitled;
 446 }
 447
 448 bool
 449 auth_token_has_entitlement_for_right(auth_token_t auth, const char * right)
 450 {
 451     __block bool entitled = false;
 452
 453     dispatch_sync(auth->dispatch_queue, ^{
 454         if (auth->creator) {
 455             entitled = process_has_entitlement_for_right(auth->creator, right);
 456         }
 457     });
 458
 459     return entitled;
 460 }
 461
 462 credential_t
 463 auth_token_get_credential(auth_token_t auth)
 464 {
 465     dispatch_sync(auth->dispatch_queue, ^{
 466         if (auth->credential == NULL) {
 467             auth->credential = credential_create(auth->auditInfo.euid);
 468         }
 469     });
 470
 471     return auth->credential;
 472 }
 473
 474 bool
 475 auth_token_apple_signed(auth_token_t auth)
 476 {
 477     return auth->appleSigned;
 478 }
 479
 480 bool auth_token_is_creator(auth_token_t auth, process_t proc)
 481 {
 482     __block bool creator = false;
 483     if (proc) {
 484         dispatch_sync(auth->dispatch_queue, ^{
 485             if (auth->creator == proc) {
 486                 creator = true;
 487             }
 488         });
 489     }
 490     return creator;
 491 }
 492
 493 void auth_token_set_state(auth_token_t auth, auth_token_state_t state)
 494 {
 495     auth->state |= state;
 496 }
 497
 498 void auth_token_clear_state(auth_token_t auth, auth_token_state_t state)
 499 {
 500     auth->state &= ~state;
 501 }
 502
 503 auth_token_state_t auth_token_get_state(auth_token_t auth)
 504 {
 505     return auth->state;
 506 }
 507
 508 bool auth_token_check_state(auth_token_t auth, auth_token_state_t state)
 509 {
 510     if (state) {
 511         return (auth->state & state) != 0;
 512     } else {
 513         return auth->state == 0;
 514     }
 515 }