Security/authd/process.c

   1 /* Copyright (c) 2012-2013 Apple Inc. All Rights Reserved. */
   2
   3 #include "process.h"
   4 #include "server.h"
   5 #include "session.h"
   6 #include "debugging.h"
   7 #include "authd_private.h"
   8 #include "authtoken.h"
   9 #include "authutilities.h"
  10 #include "ccaudit.h"
  11
  12 #include <Security/SecCode.h>
  13 #include <Security/SecRequirement.h>
  14
  15 struct _process_s {
  16     __AUTH_BASE_STRUCT_HEADER__;
  17
  18     audit_info_s auditInfo;
  19
  20     session_t session;
  21
  22     CFMutableBagRef authTokens;
  23     dispatch_queue_t dispatch_queue;
  24
  25     CFMutableSetRef connections;
  26
  27     SecCodeRef codeRef;
  28     char code_url[PATH_MAX+1];
  29     char * code_identifier;
  30     CFDataRef code_requirement_data;
  31     SecRequirementRef code_requirement;
  32     CFDictionaryRef code_entitlements;
  33
  34     mach_port_t bootstrap;
  35
  36     bool appleSigned;
  37 };
  38
  39 static void
  40 _unregister_auth_tokens(const void *value, void *context)
  41 {
  42     auth_token_t auth = (auth_token_t)value;
  43     process_t proc = (process_t)context;
  44
  45     CFIndex count = auth_token_remove_process(auth, proc);
  46     if ((count == 0)  && auth_token_check_state(auth, auth_token_state_registered)) {
  47         server_unregister_auth_token(auth);
  48     }
  49 }
  50
  51 static void
  52 _destroy_zombie_tokens(process_t proc)
  53 {
  54     LOGD("process[%i] destroy zombies, %ld auth tokens", process_get_pid(proc), CFBagGetCount(proc->authTokens));
  55     _cf_bag_iterate(proc->authTokens, ^bool(CFTypeRef value) {
  56         auth_token_t auth = (auth_token_t)value;
  57         LOGD("process[%i] %p, creator=%i, zombie=%i, process_cout=%ld", process_get_pid(proc), auth, auth_token_is_creator(auth, proc), auth_token_check_state(auth, auth_token_state_zombie), auth_token_get_process_count(auth));
  58         if (auth_token_is_creator(auth, proc) && auth_token_check_state(auth, auth_token_state_zombie) && (auth_token_get_process_count(auth) == 1)) {
  59             CFBagRemoveValue(proc->authTokens, auth);
  60         }
  61         return true;
  62     });
  63 }
  64
  65 static void
  66 _process_finalize(CFTypeRef value)
  67 {
  68     process_t proc = (process_t)value;
  69
  70     LOGV("process[%i]: deallocated %p", proc->auditInfo.pid, proc);
  71
  72     dispatch_barrier_sync(proc->dispatch_queue, ^{
  73         CFBagApplyFunction(proc->authTokens, _unregister_auth_tokens, proc);
  74     });
  75
  76     session_remove_process(proc->session, proc);
  77
  78     dispatch_release(proc->dispatch_queue);
  79     CFReleaseSafe(proc->authTokens);
  80     CFReleaseSafe(proc->connections);
  81     CFReleaseSafe(proc->session);
  82     CFReleaseSafe(proc->codeRef);
  83     CFReleaseSafe(proc->code_requirement);
  84     CFReleaseSafe(proc->code_requirement_data);
  85     CFReleaseSafe(proc->code_entitlements);
  86     free_safe(proc->code_identifier);
  87     if (proc->bootstrap != MACH_PORT_NULL) {
  88         mach_port_deallocate(mach_task_self(), proc->bootstrap);
  89     }
  90 }
  91
  92 AUTH_TYPE_INSTANCE(process,
  93                    .init = NULL,
  94                    .copy = NULL,
  95                    .finalize = _process_finalize,
  96                    .equal = NULL,
  97                    .hash = NULL,
  98                    .copyFormattingDesc = NULL,
  99                    .copyDebugDesc = NULL
 100                    );
 101
 102 static CFTypeID process_get_type_id() {
 103     static CFTypeID type_id = _kCFRuntimeNotATypeID;
 104     static dispatch_once_t onceToken;
 105
 106     dispatch_once(&onceToken, ^{
 107         type_id = _CFRuntimeRegisterClass(&_auth_type_process);
 108     });
 109
 110     return type_id;
 111 }
 112
 113 process_t
 114 process_create(const audit_info_s * auditInfo, session_t session)
 115 {
 116     OSStatus status = errSecSuccess;
 117     process_t proc = NULL;
 118     CFDictionaryRef code_info = NULL;
 119     CFURLRef code_url = NULL;
 120
 121     require(session != NULL, done);
 122     require(auditInfo != NULL, done);
 123
 124     proc = (process_t)_CFRuntimeCreateInstance(kCFAllocatorDefault, process_get_type_id(), AUTH_CLASS_SIZE(process), NULL);
 125     require(proc != NULL, done);
 126
 127     proc->auditInfo = *auditInfo;
 128
 129     proc->session = (session_t)CFRetain(session);
 130
 131     proc->connections = CFSetCreateMutable(kCFAllocatorDefault, 0, NULL);
 132
 133     proc->authTokens = CFBagCreateMutable(kCFAllocatorDefault, 0, &kCFTypeBagCallBacks);
 134     check(proc->authTokens != NULL);
 135
 136     proc->dispatch_queue = dispatch_queue_create(NULL, DISPATCH_QUEUE_SERIAL);
 137     check(proc->dispatch_queue != NULL);
 138
 139     CFMutableDictionaryRef codeDict = CFDictionaryCreateMutable(kCFAllocatorDefault, 0, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks);
 140     CFNumberRef codePid = CFNumberCreate(kCFAllocatorDefault, kCFNumberIntType, &proc->auditInfo.pid);
 141     CFDictionarySetValue(codeDict, kSecGuestAttributePid, codePid);
 142     status = SecCodeCopyGuestWithAttributes(NULL, codeDict, kSecCSDefaultFlags, &proc->codeRef);
 143     CFReleaseSafe(codeDict);
 144     CFReleaseSafe(codePid);
 145
 146     if (status) {
 147         LOGE("process[%i]: failed to create code ref %i", proc->auditInfo.pid, status);
 148         CFReleaseNull(proc);
 149         goto done;
 150     }
 151
 152     status = SecCodeCopySigningInformation(proc->codeRef, kSecCSRequirementInformation, &code_info);
 153     require_noerr_action(status, done, LOGV("process[%i]: SecCodeCopySigningInformation failed with %i", proc->auditInfo.pid, status));
 154
 155     CFTypeRef value = NULL;
 156     if (CFDictionaryGetValueIfPresent(code_info, kSecCodeInfoDesignatedRequirement, (const void**)&value)) {
 157         if (CFGetTypeID(value) == SecRequirementGetTypeID()) {
 158             SecRequirementCopyData((SecRequirementRef)value, kSecCSDefaultFlags, &proc->code_requirement_data);
 159             if (proc->code_requirement_data) {
 160                 SecRequirementCreateWithData(proc->code_requirement_data, kSecCSDefaultFlags, &proc->code_requirement);
 161             }
 162         }
 163         value = NULL;
 164     }
 165
 166     if (SecCodeCopyPath(proc->codeRef, kSecCSDefaultFlags, &code_url) == errSecSuccess) {
 167         CFURLGetFileSystemRepresentation(code_url, true, (UInt8*)proc->code_url, sizeof(proc->code_url));
 168     }
 169
 170     if (CFDictionaryGetValueIfPresent(code_info, kSecCodeInfoIdentifier, &value)) {
 171         if (CFGetTypeID(value) == CFStringGetTypeID()) {
 172             proc->code_identifier = _copy_cf_string(value, NULL);
 173         }
 174         value = NULL;
 175     }
 176
 177     if (CFDictionaryGetValueIfPresent(code_info, kSecCodeInfoEntitlementsDict, &value)) {
 178         if (CFGetTypeID(value) == CFDictionaryGetTypeID()) {
 179             proc->code_entitlements = CFDictionaryCreateCopy(kCFAllocatorDefault, value);
 180         }
 181         value = NULL;
 182     }
 183
 184     // This is the clownfish supported way to check for a Mac App Store or B&I signed build
 185     CFStringRef requirementString = CFSTR("(anchor apple) or (anchor apple generic and certificate leaf[field.1.2.840.113635.100.6.1.9])");
 186     SecRequirementRef  secRequirementRef = NULL;
 187     status = SecRequirementCreateWithString(requirementString, kSecCSDefaultFlags, &secRequirementRef);
 188     if (status == errSecSuccess) {
 189         proc->appleSigned = process_verify_requirment(proc, secRequirementRef);
 190     }
 191     CFReleaseSafe(secRequirementRef);
 192
 193     LOGV("process[%i]: created (sid=%i) %s %p", proc->auditInfo.pid, proc->auditInfo.asid, proc->code_url, proc);
 194
 195 done:
 196     CFReleaseSafe(code_info);
 197     CFReleaseSafe(code_url);
 198     return proc;
 199 }
 200
 201 const void *
 202 process_get_key(process_t proc)
 203 {
 204     return &proc->auditInfo;
 205 }
 206
 207 uid_t
 208 process_get_uid(process_t proc)
 209 {
 210     return proc ? proc->auditInfo.euid : (uid_t)-2;
 211 }
 212
 213 pid_t
 214 process_get_pid(process_t proc)
 215 {
 216     return proc ? proc->auditInfo.pid : -1;
 217 }
 218
 219 int32_t process_get_generation(process_t proc)
 220 {
 221     return proc->auditInfo.tid;
 222 }
 223
 224 session_id_t
 225 process_get_session_id(process_t proc)
 226 {
 227     return proc ? proc->auditInfo.asid : -1;
 228 }
 229
 230 session_t
 231 process_get_session(process_t proc)
 232 {
 233     return proc->session;
 234 }
 235
 236 const audit_info_s *
 237 process_get_audit_info(process_t proc)
 238 {
 239     return &proc->auditInfo;
 240 }
 241
 242 SecCodeRef
 243 process_get_code(process_t proc)
 244 {
 245     return proc->codeRef;
 246 }
 247
 248 const char *
 249 process_get_code_url(process_t proc)
 250 {
 251     return proc->code_url;
 252 }
 253
 254 void
 255 process_add_auth_token(process_t proc, auth_token_t auth)
 256 {
 257     dispatch_sync(proc->dispatch_queue, ^{
 258         CFBagAddValue(proc->authTokens, auth);
 259         if (CFBagGetCountOfValue(proc->authTokens, auth) == 1) {
 260             auth_token_add_process(auth, proc);
 261         }
 262     });
 263 }
 264
 265 void
 266 process_remove_auth_token(process_t proc, auth_token_t auth, AuthorizationFlags flags)
 267 {
 268     dispatch_sync(proc->dispatch_queue, ^{
 269         bool destroy = false;
 270         bool creator = auth_token_is_creator(auth, proc);
 271         CFIndex count = auth_token_get_process_count(auth);
 272
 273         // if we are the last ones associated with this auth token or the caller passed in the kAuthorizationFlagDestroyRights
 274         // then we break the link between the process and auth token.  If another process holds a reference
 275         // then kAuthorizationFlagDestroyRights will only break the link and not destroy the auth token
 276         // <rdar://problem/14553640>
 277         if ((count == 1) ||
 278             (flags & kAuthorizationFlagDestroyRights))
 279         {
 280             destroy = true;
 281             goto done;
 282         }
 283
 284         // If we created this token and someone else is holding a reference to it
 285         // don't destroy the link until they have freed the authorization ref
 286         // instead set the zombie state on the auth_token
 287         if (creator) {
 288             if (CFBagGetCountOfValue(proc->authTokens, auth) == 1) {
 289                 auth_token_set_state(auth, auth_token_state_zombie);
 290             } else {
 291                 destroy = true;
 292             }
 293         } else {
 294             destroy = true;
 295         }
 296
 297     done:
 298         if (destroy) {
 299             CFBagRemoveValue(proc->authTokens, auth);
 300             if (!CFBagContainsValue(proc->authTokens, auth)) {
 301                 auth_token_remove_process(auth, proc);
 302
 303                 if ((count == 1) && auth_token_check_state(auth, auth_token_state_registered)) {
 304                     server_unregister_auth_token(auth);
 305                 }
 306             }
 307         }
 308
 309         // destroy all eligible zombies
 310         _destroy_zombie_tokens(proc);
 311     });
 312 }
 313
 314 auth_token_t
 315 process_find_copy_auth_token(process_t proc, const AuthorizationBlob * blob)
 316 {
 317     __block CFTypeRef auth = NULL;
 318     dispatch_sync(proc->dispatch_queue, ^{
 319         _cf_bag_iterate(proc->authTokens, ^bool(CFTypeRef value) {
 320             auth_token_t iter = (auth_token_t)value;
 321             if (memcmp(blob, auth_token_get_blob(iter), sizeof(AuthorizationBlob)) == 0) {
 322                 auth = iter;
 323                 CFRetain(auth);
 324                 return false;
 325             }
 326             return true;
 327         });
 328     });
 329     return (auth_token_t)auth;
 330 }
 331
 332 CFIndex
 333 process_get_auth_token_count(process_t proc)
 334 {
 335     __block CFIndex count = 0;
 336     dispatch_sync(proc->dispatch_queue, ^{
 337         count = CFBagGetCount(proc->authTokens);
 338     });
 339     return count;
 340 }
 341
 342 CFIndex
 343 process_add_connection(process_t proc, connection_t conn)
 344 {
 345     __block CFIndex count = 0;
 346     dispatch_sync(proc->dispatch_queue, ^{
 347         CFSetAddValue(proc->connections, conn);
 348         count = CFSetGetCount(proc->connections);
 349     });
 350     return count;
 351 }
 352
 353 CFIndex
 354 process_remove_connection(process_t proc, connection_t conn)
 355 {
 356     __block CFIndex count = 0;
 357     dispatch_sync(proc->dispatch_queue, ^{
 358         CFSetRemoveValue(proc->connections, conn);
 359         count = CFSetGetCount(proc->connections);
 360     });
 361     return count;
 362 }
 363
 364 CFIndex
 365 process_get_connection_count(process_t proc)
 366 {
 367     __block CFIndex count = 0;
 368     dispatch_sync(proc->dispatch_queue, ^{
 369         count = CFSetGetCount(proc->connections);
 370     });
 371     return count;
 372 }
 373
 374 CFTypeRef
 375 process_copy_entitlement_value(process_t proc, const char * entitlement)
 376 {
 377     CFTypeRef value = NULL;
 378     require(entitlement != NULL, done);
 379
 380     CFStringRef key = CFStringCreateWithCStringNoCopy(kCFAllocatorDefault, entitlement, kCFStringEncodingUTF8, kCFAllocatorNull);
 381     if (proc->code_entitlements && key && (CFDictionaryGetValueIfPresent(proc->code_entitlements, key, &value))) {
 382         CFRetainSafe(value);
 383     }
 384     CFReleaseSafe(key);
 385
 386 done:
 387     return value;
 388 }
 389
 390 bool
 391 process_has_entitlement(process_t proc, const char * entitlement)
 392 {
 393     bool entitled = false;
 394     require(entitlement != NULL, done);
 395
 396     CFStringRef key = CFStringCreateWithCStringNoCopy(kCFAllocatorDefault, entitlement, kCFStringEncodingUTF8, kCFAllocatorNull);
 397     CFTypeRef value = NULL;
 398     if (proc->code_entitlements && key && (CFDictionaryGetValueIfPresent(proc->code_entitlements, key, &value))) {
 399         if (CFGetTypeID(value) == CFBooleanGetTypeID()) {
 400             entitled = CFBooleanGetValue(value);
 401         }
 402     }
 403     CFReleaseSafe(key);
 404
 405 done:
 406     return entitled;
 407 }
 408
 409 bool
 410 process_has_entitlement_for_right(process_t proc, const char * right)
 411 {
 412     bool entitled = false;
 413     require(right != NULL, done);
 414
 415     CFTypeRef rights = NULL;
 416     if (proc->code_entitlements && CFDictionaryGetValueIfPresent(proc->code_entitlements, CFSTR("com.apple.private.AuthorizationServices"), &rights)) {
 417         if (CFGetTypeID(rights) == CFArrayGetTypeID()) {
 418             CFStringRef key = CFStringCreateWithCStringNoCopy(kCFAllocatorDefault, right, kCFStringEncodingUTF8, kCFAllocatorNull);
 419             require(key != NULL, done);
 420
 421             CFIndex count = CFArrayGetCount(rights);
 422             for (CFIndex i = 0; i < count; i++) {
 423                 if (CFEqual(CFArrayGetValueAtIndex(rights, i), key)) {
 424                     entitled = true;
 425                     break;
 426                 }
 427             }
 428             CFReleaseSafe(key);
 429         }
 430     }
 431
 432 done:
 433     return entitled;
 434 }
 435
 436 const char *
 437 process_get_identifier(process_t proc)
 438 {
 439     return proc->code_identifier;
 440 }
 441
 442 CFDataRef
 443 process_get_requirement_data(process_t proc)
 444 {
 445     return proc->code_requirement_data;
 446 }
 447
 448 SecRequirementRef
 449 process_get_requirement(process_t proc)
 450 {
 451     return proc->code_requirement;
 452 }
 453
 454 bool process_verify_requirment(process_t proc, SecRequirementRef requirment)
 455 {
 456     OSStatus status = SecCodeCheckValidity(proc->codeRef, kSecCSDefaultFlags, requirment);
 457     if (status != errSecSuccess) {
 458         LOGV("process[%i]: code requirement check failed (%d)", proc->auditInfo.pid, status);
 459     }
 460     return (status == errSecSuccess);
 461 }
 462
 463 // Returns true if the process was signed by B&I or the Mac App Store
 464 bool process_apple_signed(process_t proc) {
 465     return proc->appleSigned;
 466 }
 467
 468 mach_port_t process_get_bootstrap(process_t proc)
 469 {
 470     return proc->bootstrap;
 471 }
 472
 473 bool process_set_bootstrap(process_t proc, mach_port_t bootstrap)
 474 {
 475     if (bootstrap != MACH_PORT_NULL) {
 476         if (proc->bootstrap != MACH_PORT_NULL) {
 477             mach_port_deallocate(mach_task_self(), proc->bootstrap);
 478         }
 479         proc->bootstrap = bootstrap;
 480         return true;
 481     }
 482     return false;
 483 }
 484