OSX/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 AUTHD_DEFINE_LOG
  17
  18 static Boolean AuthTokenEqualCallBack(const void *value1, const void *value2)
  19 {
  20     return (*(uint64_t*)value1) == (*(uint64_t*)value2);
  21 }
  22
  23 static CFHashCode AuthTokenHashCallBack(const void *value)
  24 {
  25 //    CFHashCode hash;
  26 //    AuthorizationBlob* blob = (AuthorizationBlob*)value;
  27 //    hash = blob->data[1];
  28 //    hash <<= 32;
  29 //    hash |= blob->data[0];
  30 //    return hash;
  31     //quick 64 bit aligned version
  32     return *((CFHashCode*)((AuthorizationBlob*)value)->data);
  33 }
  34
  35 const CFDictionaryKeyCallBacks kAuthTokenKeyCallBacks = {
  36     .version = 0,
  37     .retain = NULL,
  38     .release = NULL,
  39     .copyDescription = NULL,
  40     .equal = &AuthTokenEqualCallBack,
  41     .hash = &AuthTokenHashCallBack
  42 };
  43
  44 struct _auth_token_s {
  45     __AUTH_BASE_STRUCT_HEADER__;
  46
  47     AuthorizationBlob blob;
  48     auth_token_state_t state;
  49     audit_info_s auditInfo;
  50     dispatch_queue_t dispatch_queue;
  51
  52     CFMutableSetRef processes;
  53
  54     session_t session;
  55     process_t creator; // weak reference, used for entitlement checking
  56     mach_port_t creator_bootstrap_port;
  57
  58     auth_items_t context;
  59
  60     CFMutableSetRef credentials;
  61     CFMutableSetRef authorized_rights;
  62
  63         CFMutableDataRef encryption_key;
  64
  65     bool least_privileged;
  66     bool appleSigned;
  67         bool firstPartySigned;
  68
  69     bool sandboxed;
  70     char * code_url;
  71
  72     credential_t credential;
  73 };
  74
  75 static void
  76 _auth_token_finalize(CFTypeRef value)
  77 {
  78     auth_token_t auth = (auth_token_t)value;
  79     os_log_debug(AUTHD_LOG, "authtoken: finalizing");
  80
  81     dispatch_barrier_sync(auth->dispatch_queue, ^{});
  82
  83     dispatch_release(auth->dispatch_queue);
  84     CFReleaseNull(auth->session);
  85     CFReleaseNull(auth->processes);
  86     CFReleaseNull(auth->context);
  87     CFReleaseNull(auth->credentials);
  88     CFReleaseNull(auth->authorized_rights);
  89     free_safe(auth->code_url);
  90     CFReleaseNull(auth->credential);
  91         CFReleaseNull(auth->encryption_key);
  92
  93     if (auth->creator_bootstrap_port != MACH_PORT_NULL) {
  94         mach_port_deallocate(mach_task_self(), auth->creator_bootstrap_port);
  95                 auth->creator_bootstrap_port = MACH_PORT_NULL;
  96     }
  97 }
  98
  99 static Boolean
 100 _auth_token_equal(CFTypeRef value1, CFTypeRef value2)
 101 {
 102     auth_token_t auth1 = (auth_token_t)value1;
 103     auth_token_t auth2 = (auth_token_t)value2;
 104
 105     return memcmp(&auth1->blob, &auth2->blob, sizeof(AuthorizationBlob)) == 0;
 106 }
 107
 108 static CFStringRef
 109 _auth_token_copy_description(CFTypeRef value)
 110 {
 111     auth_token_t auth = (auth_token_t)value;
 112     return CFStringCreateWithFormat(kCFAllocatorDefault, NULL, CFSTR("auth_token: uid=%i, pid=%i, processes=%li least_privileged=%i"),
 113                                     auth->auditInfo.euid, auth->auditInfo.pid, CFSetGetCount(auth->processes), auth->least_privileged);
 114 }
 115
 116 static CFHashCode
 117 _auth_token_hash(CFTypeRef value)
 118 {
 119     auth_token_t auth = (auth_token_t)value;
 120     return *(CFHashCode*)&auth->blob;
 121 }
 122
 123 AUTH_TYPE_INSTANCE(auth_token,
 124                    .init = NULL,
 125                    .copy = NULL,
 126                    .finalize = _auth_token_finalize,
 127                    .equal = _auth_token_equal,
 128                    .hash = _auth_token_hash,
 129                    .copyFormattingDesc = NULL,
 130                    .copyDebugDesc = _auth_token_copy_description
 131                    );
 132
 133 static CFTypeID auth_token_get_type_id() {
 134     static CFTypeID type_id = _kCFRuntimeNotATypeID;
 135     static dispatch_once_t onceToken;
 136
 137     dispatch_once(&onceToken, ^{
 138         type_id = _CFRuntimeRegisterClass(&_auth_type_auth_token);
 139     });
 140
 141     return type_id;
 142 }
 143
 144 static auth_token_t
 145 _auth_token_create(const audit_info_s * auditInfo, bool operateAsLeastPrivileged)
 146 {
 147 #if __LLP64__
 148     __Check_Compile_Time(sizeof(CFHashCode) == sizeof(AuthorizationBlob));
 149 #endif
 150
 151     auth_token_t auth = (auth_token_t)_CFRuntimeCreateInstance(kCFAllocatorDefault, auth_token_get_type_id(), AUTH_CLASS_SIZE(auth_token), NULL);
 152     require(auth != NULL, done);
 153
 154     if (CCRandomCopyBytes(kCCRandomDefault, auth->blob.data, sizeof(auth->blob.data)) != kCCSuccess) {
 155         os_log_error(AUTHD_LOG, "authtoken: failed to generate blob (PID %d)", auditInfo->pid);
 156         CFReleaseNull(auth);
 157         goto done;
 158     }
 159
 160     auth->context = auth_items_create();
 161     auth->auditInfo = *auditInfo;
 162     auth->least_privileged = operateAsLeastPrivileged;
 163
 164     auth->dispatch_queue = dispatch_queue_create(NULL, DISPATCH_QUEUE_SERIAL);
 165     check(auth->dispatch_queue != NULL);
 166
 167     auth->credentials = CFSetCreateMutable(kCFAllocatorDefault, 0, &kCFTypeSetCallBacks);
 168     auth->authorized_rights = CFSetCreateMutable(kCFAllocatorDefault, 0, &kCFTypeSetCallBacks);
 169     auth->processes = CFSetCreateMutable(kCFAllocatorDefault, 0, NULL);
 170     auth->creator_bootstrap_port = MACH_PORT_NULL;
 171
 172     if (sandbox_check_by_audit_token(auth->auditInfo.opaqueToken, "authorization-right-obtain", SANDBOX_CHECK_NO_REPORT) != 0)
 173                 auth->sandboxed = true;
 174         else
 175                 auth->sandboxed = false;
 176
 177         size_t key_length = kCCKeySizeAES256;
 178         auth->encryption_key = CFDataCreateMutable(kCFAllocatorDefault, key_length);
 179         if (auth->encryption_key) {
 180                 int rv = CCRandomCopyBytes(kCCRandomDefault, CFDataGetMutableBytePtr(auth->encryption_key), key_length);
 181                 if (rv != kCCSuccess) {
 182                         CFReleaseNull(auth->encryption_key)
 183                 }
 184                 CFDataSetLength(auth->encryption_key, key_length);
 185         }
 186
 187 #if DEBUG
 188     CFHashCode code = AuthTokenHashCallBack(&auth->blob);
 189     if (memcmp(&code, auth->blob.data, sizeof(auth->blob.data)) != 0) {
 190         os_log_debug(AUTHD_LOG, "authtoken[%i]: blob = %x%01x", auth->auditInfo.pid, auth->blob.data[1], auth->blob.data[0]);
 191         os_log_debug(AUTHD_LOG, "authtoken[%i]: hash = %lx", auth->auditInfo.pid, code);
 192         assert(false);
 193     }
 194 #endif
 195
 196 done:
 197     return auth;
 198 }
 199
 200 auth_token_t
 201 auth_token_create(process_t proc, bool operateAsLeastPrivileged)
 202 {
 203     auth_token_t auth = NULL;
 204     require(proc != NULL, done);
 205
 206     auth = _auth_token_create(process_get_audit_info(proc), operateAsLeastPrivileged);
 207     require(auth != NULL, done);
 208
 209     auth->creator = proc;
 210     auth->session = (session_t)CFRetain(process_get_session(proc));
 211     auth->code_url = _copy_string(process_get_code_url(proc));
 212     auth->appleSigned = process_apple_signed(proc);
 213     auth->creator_bootstrap_port = process_get_bootstrap(proc);
 214     // This line grabs a reference to the send right to the bootstrap (our right to send to the bootstrap)
 215     // This makes it critical to use the same call in reverse as we are only getting a ref to one right,
 216     // but deallocate will free a ref to all 5 rights.
 217     if (auth->creator_bootstrap_port != MACH_PORT_NULL) {
 218         kern_return_t error_code = mach_port_mod_refs(mach_task_self(), auth->creator_bootstrap_port, MACH_PORT_RIGHT_SEND, 1);
 219         if (error_code != KERN_SUCCESS) {
 220             // If no reference to the mach port right can be obtained, we don't hold the copy, so mark it NULL again!
 221             auth->creator_bootstrap_port = MACH_PORT_NULL;
 222         }
 223     }
 224
 225     os_log_debug(AUTHD_LOG, "authtoken: created for PID %d", auth->auditInfo.pid);
 226
 227 done:
 228     return auth;
 229 }
 230
 231 bool
 232 auth_token_get_sandboxed(auth_token_t auth)
 233 {
 234     return auth->sandboxed;
 235 }
 236
 237 const char *
 238 auth_token_get_code_url(auth_token_t auth)
 239 {
 240     return auth->code_url;
 241 }
 242
 243 const void *
 244 auth_token_get_key(auth_token_t auth)
 245 {
 246     return &auth->blob;
 247 }
 248
 249 auth_items_t
 250 auth_token_get_context(auth_token_t auth)
 251 {
 252     return auth->context;
 253 }
 254
 255 bool
 256 auth_token_least_privileged(auth_token_t auth)
 257 {
 258     return auth->least_privileged;
 259 }
 260
 261 uid_t
 262 auth_token_get_uid(auth_token_t auth)
 263 {
 264     assert(auth); // marked non-null
 265     return auth->auditInfo.euid;
 266 }
 267
 268 pid_t
 269 auth_token_get_pid(auth_token_t auth)
 270 {
 271     assert(auth); // marked non-null
 272     return auth->auditInfo.pid;
 273 }
 274
 275 session_t
 276 auth_token_get_session(auth_token_t auth)
 277 {
 278     return auth->session;
 279 }
 280
 281 const AuthorizationBlob *
 282 auth_token_get_blob(auth_token_t auth)
 283 {
 284     return &auth->blob;
 285 }
 286
 287 const audit_info_s *
 288 auth_token_get_audit_info(auth_token_t auth)
 289 {
 290     return &auth->auditInfo;
 291 }
 292
 293 mach_port_t
 294 auth_token_get_creator_bootstrap(auth_token_t auth)
 295 {
 296     return auth->creator_bootstrap_port;
 297 }
 298
 299 CFIndex
 300 auth_token_add_process(auth_token_t auth, process_t proc)
 301 {
 302     __block CFIndex count = 0;
 303     dispatch_sync(auth->dispatch_queue, ^{
 304         CFSetAddValue(auth->processes, proc);
 305         count = CFSetGetCount(auth->processes);
 306     });
 307     return count;
 308 }
 309
 310 CFIndex
 311 auth_token_remove_process(auth_token_t auth, process_t proc)
 312 {
 313     __block CFIndex count = 0;
 314     dispatch_sync(auth->dispatch_queue, ^{
 315         if (auth->creator == proc) {
 316             auth->creator = NULL;
 317         }
 318         CFSetRemoveValue(auth->processes, proc);
 319         count = CFSetGetCount(auth->processes);
 320     });
 321     return count;
 322 }
 323
 324 CFIndex
 325 auth_token_get_process_count(auth_token_t auth)
 326 {
 327     __block CFIndex count = 0;
 328     dispatch_sync(auth->dispatch_queue, ^{
 329         count = CFSetGetCount(auth->processes);
 330     });
 331     return count;
 332 }
 333
 334 void
 335 auth_token_set_credential(auth_token_t auth, credential_t cred)
 336 {
 337     dispatch_sync(auth->dispatch_queue, ^{
 338         CFSetSetValue(auth->credentials, cred);
 339     });
 340 }
 341
 342 bool
 343 auth_token_credentials_iterate(auth_token_t auth, credential_iterator_t iter)
 344 {
 345     __block bool result = false;
 346
 347     dispatch_sync(auth->dispatch_queue, ^{
 348         CFIndex count = CFSetGetCount(auth->credentials);
 349         if (count > 128) { // <rdar://problem/38179345> Variable Length Arrays; AuthD
 350                            // auth_token usually contains 0 or 1 credential
 351             count = 128;
 352         }
 353         CFTypeRef values[count];
 354         CFSetGetValues(auth->credentials, values);
 355         for (CFIndex i = 0; i < count; i++) {
 356             credential_t cred = (credential_t)values[i];
 357             result = iter(cred);
 358             if (!result) {
 359                 break;
 360             }
 361         }
 362     });
 363
 364     return result;
 365 }
 366
 367 void
 368 auth_token_set_right(auth_token_t auth, credential_t right)
 369 {
 370     dispatch_sync(auth->dispatch_queue, ^{
 371         CFSetSetValue(auth->authorized_rights, right);
 372     });
 373 }
 374
 375 CFTypeRef
 376 auth_token_copy_entitlement_value(auth_token_t auth, const char * entitlement)
 377 {
 378     __block CFTypeRef value = NULL;
 379     dispatch_sync(auth->dispatch_queue, ^{
 380         if (auth->creator) {
 381             value = process_copy_entitlement_value(auth->creator, entitlement);
 382         }
 383     });
 384
 385     return value;
 386 }
 387
 388 bool
 389 auth_token_has_entitlement(auth_token_t auth, const char * entitlement)
 390 {
 391     __block bool entitled = false;
 392
 393     dispatch_sync(auth->dispatch_queue, ^{
 394         if (auth->creator) {
 395             entitled = process_has_entitlement(auth->creator, entitlement);
 396         }
 397     });
 398     os_log_debug(AUTHD_LOG, "authtoken: PID %d is%{public}s entitled for %{public}s", auth->auditInfo.pid, entitled ? "":" not", entitlement);
 399
 400     return entitled;
 401 }
 402
 403 bool
 404 auth_token_has_entitlement_for_right(auth_token_t auth, const char * right)
 405 {
 406     __block bool entitled = false;
 407
 408     dispatch_sync(auth->dispatch_queue, ^{
 409         if (auth->creator) {
 410             entitled = process_has_entitlement_for_right(auth->creator, right);
 411         }
 412     });
 413     os_log_debug(AUTHD_LOG, "authtoken: PID %d is%{public}s entitled for right %{public}s", auth->auditInfo.pid, entitled ? "":" not", right);
 414
 415     return entitled;
 416 }
 417
 418 credential_t
 419 auth_token_get_credential(auth_token_t auth)
 420 {
 421     dispatch_sync(auth->dispatch_queue, ^{
 422         if (auth->credential == NULL) {
 423             auth->credential = credential_create(auth->auditInfo.euid);
 424         }
 425     });
 426
 427     return auth->credential;
 428 }
 429
 430 bool
 431 auth_token_apple_signed(auth_token_t auth)
 432 {
 433     return auth->appleSigned;
 434 }
 435
 436 bool auth_token_is_creator(auth_token_t auth, process_t proc)
 437 {
 438     assert(proc); // marked non-null
 439     __block bool creator = false;
 440     dispatch_sync(auth->dispatch_queue, ^{
 441         if (auth->creator == proc) {
 442             creator = true;
 443         }
 444     });
 445     return creator;
 446 }
 447
 448 void auth_token_set_state(auth_token_t auth, auth_token_state_t state)
 449 {
 450     auth->state |= state;
 451 }
 452
 453 void auth_token_clear_state(auth_token_t auth, auth_token_state_t state)
 454 {
 455     auth->state &= ~state;
 456 }
 457
 458 auth_token_state_t auth_token_get_state(auth_token_t auth)
 459 {
 460     return auth->state;
 461 }
 462
 463 bool auth_token_check_state(auth_token_t auth, auth_token_state_t state)
 464 {
 465     if (state) {
 466         return (auth->state & state) != 0;
 467     } else {
 468         return auth->state == 0;
 469     }
 470 }
 471
 472 CFDataRef auth_token_get_encryption_key(auth_token_t auth)
 473 {
 474         return auth->encryption_key;
 475 }
 476