OSX/libsecurity_codesigning/lib/policyengine.cpp

   1 /*
   2  * Copyright (c) 2011-2016 Apple Inc. All Rights Reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file 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 file 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  * file.
  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
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  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23 #include "policyengine.h"
  24 #include "xar++.h"
  25 #include "quarantine++.h"
  26 #include "codesigning_dtrace.h"
  27 #include <security_utilities/cfmunge.h>
  28 #include <Security/Security.h>
  29 #include <Security/SecCodePriv.h>
  30 #include <Security/SecRequirementPriv.h>
  31 #include <Security/SecPolicyPriv.h>
  32 #include <Security/SecTrustPriv.h>
  33 #include <Security/SecCodeSigner.h>
  34 #include <Security/cssmapplePriv.h>
  35 #include <security_utilities/unix++.h>
  36 #include <notify.h>
  37
  38 #include "diskrep.h"
  39 #include "codedirectory.h"
  40 #include "csutilities.h"
  41 #include "StaticCode.h"
  42
  43 #include <CoreServices/CoreServicesPriv.h>
  44 #include "SecCodePriv.h"
  45 #undef check // Macro! Yech.
  46
  47 extern "C" {
  48 #include <OpenScriptingUtilPriv.h>
  49 }
  50
  51
  52 namespace Security {
  53 namespace CodeSigning {
  54
  55 static const double NEGATIVE_HOLD = 60.0/86400; // 60 seconds to cache negative outcomes
  56
  57 static const char RECORDER_DIR[] = "/tmp/gke-";         // recorder mode destination for detached signatures
  58 enum {
  59         recorder_code_untrusted = 0,            // signed but untrusted
  60         recorder_code_adhoc = 1,                        // unsigned; signature recorded
  61         recorder_code_unable = 2,                       // unsigned; unable to record signature
  62 };
  63
  64
  65 static void authorizeUpdate(SecAssessmentFlags flags, CFDictionaryRef context);
  66 static bool codeInvalidityExceptions(SecStaticCodeRef code, CFMutableDictionaryRef result);
  67 static CFTypeRef installerPolicy() CF_RETURNS_RETAINED;
  68
  69
  70 //
  71 // Core structure
  72 //
  73 PolicyEngine::PolicyEngine()
  74         : PolicyDatabase(NULL, SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE)
  75 {
  76 }
  77
  78 PolicyEngine::~PolicyEngine()
  79 { }
  80
  81
  82 //
  83 // Top-level evaluation driver
  84 //
  85 void PolicyEngine::evaluate(CFURLRef path, AuthorityType type, SecAssessmentFlags flags, CFDictionaryRef context, CFMutableDictionaryRef result)
  86 {
  87     // update GKE
  88     installExplicitSet(gkeAuthFile, gkeSigsFile);
  89
  90     // find the global evaluation manager
  91     EvaluationManager *evaluationManager = EvaluationManager::globalManager();
  92
  93     // perform the evaluation
  94     EvaluationTask *evaluationTask = evaluationManager->evaluationTask(this, path, type, flags, context, result);
  95     evaluationManager->finalizeTask(evaluationTask, flags, result);
  96
  97     // if rejected, reset the automatic rearm timer
  98     if (CFDictionaryGetValue(result, kSecAssessmentAssessmentVerdict) == kCFBooleanFalse)
  99         resetRearmTimer("reject");
 100 }
 101
 102
 103 //
 104 // Create GKE whitelist filter screens.
 105 // These are strings that are used to determine quickly whether unsigned code may
 106 // have a GKE-style whitelist entry in the authority database. The idea is to make
 107 // up a decent hash quickly.
 108 //
 109 // Note: We continue to use SHA1 here for compatibility of existing GKE entries.
 110 // These are a prescreen, backed up by code signature checks later on. Use of SHA1 here is not a security problem.
 111 //
 112 static std::string createWhitelistScreen(char type, const Byte *digest, size_t length)
 113 {
 114         char buffer[2*length + 2];
 115         buffer[0] = type;
 116         for (size_t n = 0; n < length; n++)
 117                 sprintf(buffer + 1 + 2*n, "%02.2x", digest[n]);
 118         return buffer;
 119 }
 120
 121 static std::string createWhitelistScreen(SecStaticCodeRef code)
 122 {
 123         DiskRep *rep = SecStaticCode::requiredStatic(code)->diskRep();
 124         std::string screen;
 125         if (CFRef<CFDataRef> info = rep->component(cdInfoSlot)) {
 126                 // has an Info.plist - hash it
 127                 SHA1 hash;
 128                 hash.update(CFDataGetBytePtr(info), CFDataGetLength(info));
 129                 SHA1::Digest digest;
 130                 hash.finish(digest);
 131                 return createWhitelistScreen('I', digest, sizeof(digest));
 132         } else if (CFRef<CFDataRef> repSpecific = rep->component(cdRepSpecificSlot)) {
 133                 // has a rep-specific slot - hash that (this catches disk images cheaply)
 134                 // got invented after SHA-1 deprecation, so we'll use SHA256, which is the new default
 135                 CCHashInstance hash(kCCDigestSHA256);
 136                 hash.update(CFDataGetBytePtr(repSpecific), CFDataGetLength(repSpecific));
 137                 Byte digest[256/8];
 138                 hash.finish(digest);
 139                 return createWhitelistScreen('R', digest, sizeof(digest));
 140         } else if (rep->mainExecutableImage()) {
 141                 // stand-alone Mach-O executables are always candidates
 142                 return "N";
 143         } else {
 144                 // if everything else fails, hash the (single) file
 145                 SHA1 hash;
 146                 hashFileData(rep->mainExecutablePath().c_str(), &hash);
 147                 SHA1::Digest digest;
 148                 hash.finish(digest);
 149                 return createWhitelistScreen('M', digest, sizeof(digest));
 150         }
 151 }
 152
 153
 154 void PolicyEngine::evaluateCodeItem(SecStaticCodeRef code, CFURLRef path, AuthorityType type, SecAssessmentFlags flags, bool nested, CFMutableDictionaryRef result)
 155 {
 156
 157         SQLite::Statement query(*this,
 158                 "SELECT allow, requirement, id, label, expires, flags, disabled, filter_unsigned, remarks FROM scan_authority"
 159                 " WHERE type = :type"
 160                 " ORDER BY priority DESC;");
 161         query.bind(":type").integer(type);
 162
 163         SQLite3::int64 latentID = 0;            // first (highest priority) disabled matching ID
 164         std::string latentLabel;                        // ... and associated label, if any
 165
 166     secdebug("gk", "evaluateCodeItem type=%d flags=0x%x nested=%d path=%s", type, int(flags), nested, cfString(path).c_str());
 167         while (query.nextRow()) {
 168                 bool allow = int(query[0]);
 169                 const char *reqString = query[1];
 170                 SQLite3::int64 id = query[2];
 171                 const char *label = query[3];
 172                 double expires = query[4];
 173                 sqlite3_int64 ruleFlags = query[5];
 174                 SQLite3::int64 disabled = query[6];
 175 //              const char *filter = query[7];
 176 //              const char *remarks = query[8];
 177
 178         secdebug("gk", "considering rule %d(%s) requirement %s", int(id), label ? label : "UNLABELED", reqString);
 179                 CFRef<SecRequirementRef> requirement;
 180                 MacOSError::check(SecRequirementCreateWithString(CFTempString(reqString), kSecCSDefaultFlags, &requirement.aref()));
 181                 switch (OSStatus rc = SecStaticCodeCheckValidity(code, kSecCSBasicValidateOnly | kSecCSCheckGatekeeperArchitectures, requirement)) {
 182                 case errSecSuccess:
 183                         break;                                          // rule match; process below
 184                 case errSecCSReqFailed:
 185                         continue;                                       // rule does not apply
 186                 case errSecCSVetoed:
 187                         return;                                         // nested code has failed to pass
 188                 default:
 189                         MacOSError::throwMe(rc);        // general error; pass to caller
 190                 }
 191
 192                 // if this rule is disabled, skip it but record the first matching one for posterity
 193                 if (disabled && latentID == 0) {
 194                         latentID = id;
 195                         latentLabel = label ? label : "";
 196                         continue;
 197                 }
 198
 199                 // current rule is first rule (in priority order) that matched. Apply it
 200         secnotice("gk", "rule %d applies - allow=%d", int(id), allow);
 201                 if (nested && allow)                    // success, nothing to record
 202                         return;
 203
 204                 CFRef<CFDictionaryRef> info;    // as needed
 205                 if (flags & kSecAssessmentFlagRequestOrigin) {
 206                         if (!info)
 207                                 MacOSError::check(SecCodeCopySigningInformation(code, kSecCSSigningInformation, &info.aref()));
 208                         if (CFArrayRef chain = CFArrayRef(CFDictionaryGetValue(info, kSecCodeInfoCertificates)))
 209                                 setOrigin(chain, result);
 210                 }
 211                 if (!(ruleFlags & kAuthorityFlagInhibitCache) && !(flags & kSecAssessmentFlagNoCache)) {        // cache inhibit
 212                         if (!info)
 213                                 MacOSError::check(SecCodeCopySigningInformation(code, kSecCSSigningInformation, &info.aref()));
 214                         if (SecTrustRef trust = SecTrustRef(CFDictionaryGetValue(info, kSecCodeInfoTrust))) {
 215                                 CFRef<CFDictionaryRef> xinfo;
 216                                 MacOSError::check(SecTrustCopyExtendedResult(trust, &xinfo.aref()));
 217                                 if (CFDateRef limit = CFDateRef(CFDictionaryGetValue(xinfo, kSecTrustExpirationDate))) {
 218                                         this->recordOutcome(code, allow, type, min(expires, dateToJulian(limit)), id);
 219                                 }
 220                         }
 221                 }
 222                 if (allow) {
 223                         if (SYSPOLICY_ASSESS_OUTCOME_ACCEPT_ENABLED()) {
 224                                 if (!info)
 225                                         MacOSError::check(SecCodeCopySigningInformation(code, kSecCSSigningInformation, &info.aref()));
 226                                 CFDataRef cdhash = CFDataRef(CFDictionaryGetValue(info, kSecCodeInfoUnique));
 227                                 SYSPOLICY_ASSESS_OUTCOME_ACCEPT(cfString(path).c_str(), type, label, cdhash ? CFDataGetBytePtr(cdhash) : NULL);
 228                         }
 229                 } else {
 230                         if (SYSPOLICY_ASSESS_OUTCOME_DENY_ENABLED() || SYSPOLICY_RECORDER_MODE_ENABLED()) {
 231                                 if (!info)
 232                                         MacOSError::check(SecCodeCopySigningInformation(code, kSecCSSigningInformation, &info.aref()));
 233                                 CFDataRef cdhash = CFDataRef(CFDictionaryGetValue(info, kSecCodeInfoUnique));
 234                                 std::string cpath = cfString(path);
 235                                 const void *hashp = cdhash ? CFDataGetBytePtr(cdhash) : NULL;
 236                                 SYSPOLICY_ASSESS_OUTCOME_DENY(cpath.c_str(), type, label, hashp);
 237                                 SYSPOLICY_RECORDER_MODE(cpath.c_str(), type, label, hashp, recorder_code_untrusted);
 238                         }
 239                 }
 240                 cfadd(result, "{%O=%B}", kSecAssessmentAssessmentVerdict, allow);
 241                 addAuthority(flags, result, label, id, NULL, false, ruleFlags);
 242                 return;
 243         }
 244
 245         // no applicable authority (but signed, perhaps temporarily). Deny by default
 246     secnotice("gk", "rejecting due to lack of matching active rule");
 247         CFRef<CFDictionaryRef> info;
 248         MacOSError::check(SecCodeCopySigningInformation(code, kSecCSSigningInformation, &info.aref()));
 249         if (flags & kSecAssessmentFlagRequestOrigin) {
 250                 if (CFArrayRef chain = CFArrayRef(CFDictionaryGetValue(info, kSecCodeInfoCertificates)))
 251                         setOrigin(chain, result);
 252         }
 253         if (SYSPOLICY_ASSESS_OUTCOME_DEFAULT_ENABLED() || SYSPOLICY_RECORDER_MODE_ENABLED()) {
 254                 CFDataRef cdhash = CFDataRef(CFDictionaryGetValue(info, kSecCodeInfoUnique));
 255                 const void *hashp = cdhash ? CFDataGetBytePtr(cdhash) : NULL;
 256                 std::string cpath = cfString(path);
 257                 SYSPOLICY_ASSESS_OUTCOME_DEFAULT(cpath.c_str(), type, latentLabel.c_str(), hashp);
 258                 SYSPOLICY_RECORDER_MODE(cpath.c_str(), type, latentLabel.c_str(), hashp, 0);
 259         }
 260         if (!(flags & kSecAssessmentFlagNoCache))
 261                 this->recordOutcome(code, false, type, this->julianNow() + NEGATIVE_HOLD, latentID);
 262         cfadd(result, "{%O=%B}", kSecAssessmentAssessmentVerdict, false);
 263         addAuthority(flags, result, latentLabel.c_str(), latentID);
 264 }
 265
 266
 267 void PolicyEngine::adjustValidation(SecStaticCodeRef code)
 268 {
 269         CFRef<CFDictionaryRef> conditions = mOpaqueWhitelist.validationConditionsFor(code);
 270         SecStaticCodeSetValidationConditions(code, conditions);
 271 }
 272
 273
 274 bool PolicyEngine::temporarySigning(SecStaticCodeRef code, AuthorityType type, CFURLRef path, SecAssessmentFlags matchFlags)
 275 {
 276     secnotice("gk", "temporarySigning type=%d matchFlags=0x%x path=%s", type, int(matchFlags), cfString(path).c_str());
 277
 278     // see if we have a screened record to take matchFlags from
 279     std::string screen = createWhitelistScreen(code);
 280     SQLite::Statement query(*this,
 281         "SELECT flags FROM authority "
 282         "WHERE type = :type"
 283         " AND NOT flags & :flag"
 284         " AND CASE WHEN filter_unsigned IS NULL THEN remarks = :remarks ELSE filter_unsigned = :screen END");
 285     query.bind(":type").integer(type);
 286     query.bind(":flag").integer(kAuthorityFlagDefault);
 287     query.bind(":screen") = screen;
 288     query.bind(":remarks") = cfString(path);
 289     secdebug("gk", "match screen=%s", screen.c_str());
 290     if (query.nextRow())        // got a matching rule
 291         matchFlags = SQLite3::int64(query[0]);
 292     else if (matchFlags == 0)  // lazy and no match
 293         return false;
 294     secdebug("gk", "matchFlags found=0x%x", int(matchFlags));
 295
 296         try {
 297                 // ad-hoc sign the code and attach the signature
 298                 CFRef<CFDataRef> signature = CFDataCreateMutable(NULL, 0);
 299                 CFTemp<CFMutableDictionaryRef> arguments("{%O=%O, %O=#N, %O=%d}", kSecCodeSignerDetached, signature.get(), kSecCodeSignerIdentity,
 300                         kSecCodeSignerDigestAlgorithm, (matchFlags & kAuthorityFlagWhitelistSHA256) ? kSecCodeSignatureHashSHA256 : kSecCodeSignatureHashSHA1);
 301                 // for modern whitelist entries, neuter the identifier since it may be derived from the filename
 302                 if (matchFlags & kAuthorityFlagWhitelistSHA256)
 303                         CFDictionaryAddValue(arguments, kSecCodeSignerIdentifier, CFSTR("ADHOC"));
 304                 CFRef<SecCodeSignerRef> signer;
 305                 MacOSError::check(SecCodeSignerCreate(arguments, (matchFlags & kAuthorityFlagWhitelistV2) ? kSecCSSignOpaque : kSecCSSignV1, &signer.aref()));
 306                 MacOSError::check(SecCodeSignerAddSignature(signer, code, kSecCSDefaultFlags));
 307                 MacOSError::check(SecCodeSetDetachedSignature(code, signature, kSecCSDefaultFlags));
 308
 309                 SecRequirementRef dr = NULL;
 310                 SecCodeCopyDesignatedRequirement(code, kSecCSDefaultFlags, &dr);
 311                 CFStringRef drs = NULL;
 312                 SecRequirementCopyString(dr, kSecCSDefaultFlags, &drs);
 313         secnotice("gk", "successfully created temporary signature - requirement=%s", cfString(drs).c_str());
 314
 315                 // if we're in GKE recording mode, save that signature and report its location
 316                 if (SYSPOLICY_RECORDER_MODE_ENABLED()) {
 317                         int status = recorder_code_unable;      // ephemeral signature (not recorded)
 318                         if (geteuid() == 0) {
 319                                 CFRef<CFUUIDRef> uuid = CFUUIDCreate(NULL);
 320                                 std::string sigfile = RECORDER_DIR + cfStringRelease(CFUUIDCreateString(NULL, uuid)) + ".tsig";
 321                                 try {
 322                                         UnixPlusPlus::AutoFileDesc fd(sigfile, O_WRONLY | O_CREAT);
 323                                         fd.write(CFDataGetBytePtr(signature), CFDataGetLength(signature));
 324                                         status = recorder_code_adhoc;   // recorded signature
 325                                         SYSPOLICY_RECORDER_MODE_ADHOC_PATH(cfString(path).c_str(), type, sigfile.c_str());
 326                                 } catch (...) { }
 327                         }
 328
 329                         // now report the D probe itself
 330                         CFRef<CFDictionaryRef> info;
 331                         MacOSError::check(SecCodeCopySigningInformation(code, kSecCSDefaultFlags, &info.aref()));
 332                         CFDataRef cdhash = CFDataRef(CFDictionaryGetValue(info, kSecCodeInfoUnique));
 333                         SYSPOLICY_RECORDER_MODE(cfString(path).c_str(), type, "",
 334                                 cdhash ? CFDataGetBytePtr(cdhash) : NULL, status);
 335                 }
 336
 337                 return true;    // it worked; we're now (well) signed
 338         } catch (...) { }
 339
 340         return false;
 341 }
 342
 343
 344 //
 345 // Executable code.
 346 // Read from disk, evaluate properly, cache as indicated.
 347 //
 348 void PolicyEngine::evaluateCode(CFURLRef path, AuthorityType type, SecAssessmentFlags flags, CFDictionaryRef context, CFMutableDictionaryRef result, bool handleUnsigned)
 349 {
 350         // not really a Gatekeeper function... but reject all "hard quarantined" files because they were made from sandboxed sources without download privilege
 351     if (type == kAuthorityExecute) {
 352         FileQuarantine qtn(cfString(path).c_str());
 353         if (qtn.flag(QTN_FLAG_HARD))
 354             MacOSError::throwMe(errSecCSFileHardQuarantined);
 355     }
 356
 357         // hack: if caller passed a UTI, use that to turn off app-only checks for some well-known ones
 358         bool appOk = false;
 359         if (CFStringRef uti = CFStringRef(CFDictionaryGetValue(context, kSecAssessmentContextKeyUTI))) {
 360                 appOk = CFEqual(uti, CFSTR("com.apple.systempreference.prefpane"))
 361                         || CFEqual(uti, CFSTR("com.apple.systempreference.screen-saver"))
 362                         || CFEqual(uti, CFSTR("com.apple.systempreference.screen-slide-saver"))
 363                         || CFEqual(uti, CFSTR("com.apple.menu-extra"));
 364         }
 365
 366         CFCopyRef<SecStaticCodeRef> code;
 367         MacOSError::check(SecStaticCodeCreateWithPath(path, kSecCSDefaultFlags, &code.aref()));
 368
 369         SecCSFlags validationFlags = kSecCSEnforceRevocationChecks | kSecCSCheckAllArchitectures;
 370         if (!(flags & kSecAssessmentFlagAllowWeak))
 371                 validationFlags |= kSecCSStrictValidate;
 372         adjustValidation(code);
 373
 374         // deal with a very special case (broken 10.6/10.7 Applet bundles)
 375         OSStatus rc = SecStaticCodeCheckValidity(code, validationFlags | kSecCSBasicValidateOnly, NULL);
 376         if (rc == errSecCSSignatureFailed) {
 377                 if (!codeInvalidityExceptions(code, result)) {  // invalidly signed, no exceptions -> error
 378                         if (SYSPOLICY_ASSESS_OUTCOME_BROKEN_ENABLED())
 379                                 SYSPOLICY_ASSESS_OUTCOME_BROKEN(cfString(path).c_str(), type, false);
 380                         MacOSError::throwMe(rc);
 381                 }
 382                 // recognized exception - treat as unsigned
 383                 if (SYSPOLICY_ASSESS_OUTCOME_BROKEN_ENABLED())
 384                         SYSPOLICY_ASSESS_OUTCOME_BROKEN(cfString(path).c_str(), type, true);
 385                 rc = errSecCSUnsigned;
 386         }
 387
 388         // ad-hoc sign unsigned code
 389     bool wasAdhocSigned = false;
 390         if (rc == errSecCSUnsigned && handleUnsigned && (!overrideAssessment(flags) || SYSPOLICY_RECORDER_MODE_ENABLED())) {
 391                 if (temporarySigning(code, type, path, 0)) {
 392             wasAdhocSigned = true;
 393                         rc = errSecSuccess;             // clear unsigned; we are now well-signed
 394                         validationFlags |= kSecCSBasicValidateOnly;     // no need to re-validate deep contents
 395                 }
 396         }
 397
 398         // prepare for deep traversal of (hopefully) good signatures
 399         SecAssessmentFeedback feedback = SecAssessmentFeedback(CFDictionaryGetValue(context, kSecAssessmentContextKeyFeedback));
 400         __block CFRef<CFMutableDictionaryRef> nestedFailure = NULL;     // save a nested failure for later
 401         MacOSError::check(SecStaticCodeSetCallback(code, kSecCSDefaultFlags, NULL, ^CFTypeRef (SecStaticCodeRef item, CFStringRef cfStage, CFDictionaryRef info) {
 402                 string stage = cfString(cfStage);
 403                 if (stage == "prepared") {
 404                         if (!CFEqual(item, code))       // genuine nested (not top) code
 405                                 adjustValidation(item);
 406                 } else if (stage == "progress") {
 407                         if (feedback && CFEqual(item, code)) {  // top level progress
 408                                 bool proceed = feedback(kSecAssessmentFeedbackProgress, info);
 409                                 if (!proceed)
 410                                         SecStaticCodeCancelValidation(code, kSecCSDefaultFlags);
 411                         }
 412                 } else if (stage == "validated") {
 413                         SecStaticCodeSetCallback(item, kSecCSDefaultFlags, NULL, NULL);         // clear callback to avoid unwanted recursion
 414                         evaluateCodeItem(item, path, type, flags, item != code, result);
 415                         if (CFTypeRef verdict = CFDictionaryGetValue(result, kSecAssessmentAssessmentVerdict))
 416                                 if (CFEqual(verdict, kCFBooleanFalse)) {
 417                                         if (item == code)
 418                                                 return makeCFNumber(OSStatus(errSecCSVetoed));  // (signal nested-code policy failure, picked up below)
 419                                         // nested code policy failure; save, reset, and continue
 420                                         if (!nestedFailure)
 421                                                 nestedFailure = CFMutableDictionaryRef(CFDictionaryGetValue(result, kSecAssessmentAssessmentAuthority));
 422                                         CFDictionaryRemoveValue(result, kSecAssessmentAssessmentAuthority);
 423                                         CFDictionaryRemoveValue(result, kSecAssessmentAssessmentVerdict);
 424                                 }
 425                 }
 426                 return NULL;
 427         }));
 428
 429         // go for it!
 430         SecCSFlags topFlags = validationFlags | kSecCSCheckNestedCode | kSecCSRestrictSymlinks | kSecCSReportProgress;
 431         if (type == kAuthorityExecute && !appOk)
 432                 topFlags |= kSecCSRestrictToAppLike;
 433         switch (rc = SecStaticCodeCheckValidity(code, topFlags, NULL)) {
 434         case errSecSuccess:             // continue below
 435                 break;
 436         case errSecCSUnsigned:
 437                 cfadd(result, "{%O=#F}", kSecAssessmentAssessmentVerdict);
 438                 addAuthority(flags, result, "no usable signature");
 439                 return;
 440         case errSecCSVetoed:            // nested code rejected by rule book; result was filled out there
 441         if (wasAdhocSigned)
 442             addToAuthority(result, kSecAssessmentAssessmentSource, CFSTR("no usable signature"));   // ad-hoc signature proved useless
 443                 return;
 444         case errSecCSWeakResourceRules:
 445         case errSecCSWeakResourceEnvelope:
 446         case errSecCSResourceNotSupported:
 447         case errSecCSAmbiguousBundleFormat:
 448         case errSecCSSignatureNotVerifiable:
 449         case errSecCSRegularFile:
 450         case errSecCSBadMainExecutable:
 451         case errSecCSBadFrameworkVersion:
 452         case errSecCSUnsealedAppRoot:
 453         case errSecCSUnsealedFrameworkRoot:
 454         case errSecCSInvalidSymlink:
 455         case errSecCSNotAppLike:
 456         {
 457                 // consult the whitelist
 458                 bool allow = false;
 459                 const char *label;
 460                 // we've bypassed evaluateCodeItem before we failed validation. Explicitly apply it now
 461                 SecStaticCodeSetCallback(code, kSecCSDefaultFlags, NULL, NULL);
 462                 evaluateCodeItem(code, path, type, flags | kSecAssessmentFlagNoCache, false, result);
 463                 if (CFTypeRef verdict = CFDictionaryGetValue(result, kSecAssessmentAssessmentVerdict)) {
 464                         // verdict rendered from a nested component - signature not acceptable to Gatekeeper
 465                         if (CFEqual(verdict, kCFBooleanFalse))  // nested code rejected by rule book; result was filled out there
 466                                 return;
 467                         if (CFEqual(verdict, kCFBooleanTrue) && !(flags & kSecAssessmentFlagIgnoreWhitelist))
 468                                 if (mOpaqueWhitelist.contains(code, feedback, rc))
 469                                         allow = true;
 470                 }
 471                 if (allow) {
 472                         label = "allowed cdhash";
 473                 } else {
 474                         CFDictionaryReplaceValue(result, kSecAssessmentAssessmentVerdict, kCFBooleanFalse);
 475                         label = "obsolete resource envelope";
 476                 }
 477                 cfadd(result, "{%O=%d}", kSecAssessmentAssessmentCodeSigningError, rc);
 478                 addAuthority(flags, result, label, 0, NULL, true);
 479                 return;
 480         }
 481         default:
 482                 MacOSError::throwMe(rc);
 483         }
 484
 485         if (nestedFailure && CFEqual(CFDictionaryGetValue(result, kSecAssessmentAssessmentVerdict), kCFBooleanTrue)) {
 486                 // structure intact, top level approved, nested code failed policy
 487                 CFMutableDictionaryRef authority = CFMutableDictionaryRef(CFDictionaryGetValue(result, kSecAssessmentAssessmentAuthority));
 488                 uint64_t ruleFlags = cfNumber<uint64_t>(CFNumberRef(CFDictionaryGetValue(authority, kSecAssessmentAssessmentAuthorityFlags)));
 489                 if (ruleFlags & kAuthorityFlagDefault) {
 490                         // default rule requires positive match at each nested code - reinstate failure
 491                         CFDictionaryReplaceValue(result, kSecAssessmentAssessmentVerdict, kCFBooleanFalse);
 492                         CFDictionaryReplaceValue(result, kSecAssessmentAssessmentAuthority, nestedFailure);
 493                 }
 494         }
 495 }
 496
 497
 498 //
 499 // Installer archive.
 500 // Hybrid policy: If we detect an installer signature, use and validate that.
 501 // If we don't, check for a code signature instead.
 502 //
 503 void PolicyEngine::evaluateInstall(CFURLRef path, SecAssessmentFlags flags, CFDictionaryRef context, CFMutableDictionaryRef result)
 504 {
 505         const AuthorityType type = kAuthorityInstall;
 506
 507         // check for recent explicit approval, using a bookmark's FileResourceIdentifierKey
 508         if (CFRef<CFDataRef> bookmark = cfLoadFile(lastApprovedFile)) {
 509                 Boolean stale;
 510                 if (CFRef<CFURLRef> url = CFURLCreateByResolvingBookmarkData(NULL, bookmark,
 511                         kCFBookmarkResolutionWithoutUIMask | kCFBookmarkResolutionWithoutMountingMask, NULL, NULL, &stale, NULL))
 512                         if (CFRef<CFDataRef> savedIdent = CFDataRef(CFURLCreateResourcePropertyForKeyFromBookmarkData(NULL, kCFURLFileResourceIdentifierKey, bookmark)))
 513                                 if (CFRef<CFDateRef> savedMod = CFDateRef(CFURLCreateResourcePropertyForKeyFromBookmarkData(NULL, kCFURLContentModificationDateKey, bookmark))) {
 514                                         CFRef<CFDataRef> currentIdent;
 515                                         CFRef<CFDateRef> currentMod;
 516                                         if (CFURLCopyResourcePropertyForKey(path, kCFURLFileResourceIdentifierKey, &currentIdent.aref(), NULL))
 517                                                 if (CFURLCopyResourcePropertyForKey(path, kCFURLContentModificationDateKey, &currentMod.aref(), NULL))
 518                                                         if (CFEqual(savedIdent, currentIdent) && CFEqual(savedMod, currentMod)) {
 519                                                                 cfadd(result, "{%O=#T}", kSecAssessmentAssessmentVerdict);
 520                                                                 addAuthority(flags, result, "explicit preference");
 521                                                                 return;
 522                                                         }
 523                                 }
 524         }
 525
 526         Xar xar(cfString(path).c_str());
 527         if (!xar) {
 528                 // follow the code signing path
 529                 evaluateCode(path, type, flags, context, result, true);
 530                 return;
 531         }
 532
 533         SQLite3::int64 latentID = 0;            // first (highest priority) disabled matching ID
 534         std::string latentLabel;                        // ... and associated label, if any
 535         if (!xar.isSigned()) {
 536                 // unsigned xar
 537                 if (SYSPOLICY_ASSESS_OUTCOME_UNSIGNED_ENABLED())
 538                         SYSPOLICY_ASSESS_OUTCOME_UNSIGNED(cfString(path).c_str(), type);
 539                 cfadd(result, "{%O=#F}", kSecAssessmentAssessmentVerdict);
 540                 addAuthority(flags, result, "no usable signature");
 541                 return;
 542         }
 543         if (CFRef<CFArrayRef> certs = xar.copyCertChain()) {
 544                 CFRef<CFTypeRef> policy = installerPolicy();
 545                 CFRef<SecTrustRef> trust;
 546                 MacOSError::check(SecTrustCreateWithCertificates(certs, policy, &trust.aref()));
 547 //              MacOSError::check(SecTrustSetAnchorCertificates(trust, cfEmptyArray())); // no anchors
 548                 MacOSError::check(SecTrustSetOptions(trust, kSecTrustOptionAllowExpired | kSecTrustOptionImplicitAnchors));
 549
 550                 SecTrustResultType trustResult;
 551                 MacOSError::check(SecTrustEvaluate(trust, &trustResult));
 552                 CFRef<CFArrayRef> chain;
 553                 CSSM_TP_APPLE_EVIDENCE_INFO *info;
 554                 MacOSError::check(SecTrustGetResult(trust, &trustResult, &chain.aref(), &info));
 555
 556                 if (flags & kSecAssessmentFlagRequestOrigin)
 557                         setOrigin(chain, result);
 558
 559                 switch (trustResult) {
 560                 case kSecTrustResultProceed:
 561                 case kSecTrustResultUnspecified:
 562                         break;
 563                 default:
 564                         {
 565                                 OSStatus rc;
 566                                 MacOSError::check(SecTrustGetCssmResultCode(trust, &rc));
 567                                 MacOSError::throwMe(rc);
 568                         }
 569                 }
 570
 571                 SQLite::Statement query(*this,
 572                         "SELECT allow, requirement, id, label, flags, disabled FROM scan_authority"
 573                         " WHERE type = :type"
 574                         " ORDER BY priority DESC;");
 575                 query.bind(":type").integer(type);
 576                 while (query.nextRow()) {
 577                         bool allow = int(query[0]);
 578                         const char *reqString = query[1];
 579                         SQLite3::int64 id = query[2];
 580                         const char *label = query[3];
 581                         //sqlite_uint64 ruleFlags = query[4];
 582                         SQLite3::int64 disabled = query[5];
 583
 584                         CFRef<SecRequirementRef> requirement;
 585                         MacOSError::check(SecRequirementCreateWithString(CFTempString(reqString), kSecCSDefaultFlags, &requirement.aref()));
 586                         switch (OSStatus rc = SecRequirementEvaluate(requirement, chain, NULL, kSecCSDefaultFlags)) {
 587                         case errSecSuccess: // success
 588                                 break;
 589                         case errSecCSReqFailed: // requirement missed, but otherwise okay
 590                                 continue;
 591                         default: // broken in some way; all tests will fail like this so bail out
 592                                 MacOSError::throwMe(rc);
 593                         }
 594                         if (disabled) {
 595                                 if (latentID == 0) {
 596                                         latentID = id;
 597                                         if (label)
 598                                                 latentLabel = label;
 599                                 }
 600                                 continue;       // the loop
 601                         }
 602
 603                         if (SYSPOLICY_ASSESS_OUTCOME_ACCEPT_ENABLED() || SYSPOLICY_ASSESS_OUTCOME_DENY_ENABLED()) {
 604                                 if (allow)
 605                                         SYSPOLICY_ASSESS_OUTCOME_ACCEPT(cfString(path).c_str(), type, label, NULL);
 606                                 else
 607                                         SYSPOLICY_ASSESS_OUTCOME_DENY(cfString(path).c_str(), type, label, NULL);
 608                         }
 609
 610                         // not adding to the object cache - we could, but it's not likely to be worth it
 611                         cfadd(result, "{%O=%B}", kSecAssessmentAssessmentVerdict, allow);
 612                         addAuthority(flags, result, label, id);
 613                         return;
 614                 }
 615         }
 616         if (SYSPOLICY_ASSESS_OUTCOME_DEFAULT_ENABLED())
 617                 SYSPOLICY_ASSESS_OUTCOME_DEFAULT(cfString(path).c_str(), type, latentLabel.c_str(), NULL);
 618
 619         // no applicable authority. Deny by default
 620         cfadd(result, "{%O=#F}", kSecAssessmentAssessmentVerdict);
 621         addAuthority(flags, result, latentLabel.c_str(), latentID);
 622 }
 623
 624
 625 //
 626 // Create a suitable policy array for verification of installer signatures.
 627 //
 628 static SecPolicyRef makeRevocationPolicy()
 629 {
 630         CFRef<SecPolicyRef> policy(SecPolicyCreateRevocation(kSecRevocationUseAnyAvailableMethod));
 631         return policy.yield();
 632 }
 633
 634 static CFTypeRef installerPolicy()
 635 {
 636         CFRef<SecPolicyRef> base = SecPolicyCreateBasicX509();
 637         CFRef<SecPolicyRef> revoc = makeRevocationPolicy();
 638         return makeCFArray(2, base.get(), revoc.get());
 639 }
 640
 641
 642 //
 643 // LaunchServices-layer document open.
 644 // We don't cache those at present. If we ever do, we need to authenticate CoreServicesUIAgent as the source of its risk assessment.
 645 //
 646 void PolicyEngine::evaluateDocOpen(CFURLRef path, SecAssessmentFlags flags, CFDictionaryRef context, CFMutableDictionaryRef result)
 647 {
 648         if (context) {
 649                 FileQuarantine qtn(cfString(path).c_str());
 650                 if (CFDictionaryGetValue(context, kSecAssessmentContextKeyPrimarySignature) == kCFBooleanTrue) {
 651                         // Client requests that we focus on the code signature on this document and report on that.
 652                         // On this path, we care about the (code) signature on the document, not its risk assessment,
 653                         // and any exception is reported as a primary error.
 654                         if (qtn.flag(QTN_FLAG_ASSESSMENT_OK)) {
 655                                 // previously added by user - hacked to say no/no usable signature to trigger proper DMG processing in XProtect
 656                                 cfadd(result, "{%O=#F}", kSecAssessmentAssessmentVerdict);
 657                 addAuthority(flags, result, "no usable signature");
 658                                 return;
 659                         }
 660                         evaluateCode(path, kAuthorityOpenDoc, flags, context, result, true);
 661                         return;
 662                 }
 663                 if (CFStringRef riskCategory = CFStringRef(CFDictionaryGetValue(context, kLSDownloadRiskCategoryKey))) {
 664
 665                         if (CFEqual(riskCategory, kLSRiskCategorySafe)
 666                                 || CFEqual(riskCategory, kLSRiskCategoryNeutral)
 667                                 || CFEqual(riskCategory, kLSRiskCategoryUnknown)
 668                                 || CFEqual(riskCategory, kLSRiskCategoryMayContainUnsafeExecutable)) {
 669                                 cfadd(result, "{%O=#T}", kSecAssessmentAssessmentVerdict);
 670                                 addAuthority(flags, result, "_XProtect");
 671                         } else if (qtn.flag(QTN_FLAG_HARD)) {
 672                                 MacOSError::throwMe(errSecCSFileHardQuarantined);
 673                         } else if (qtn.flag(QTN_FLAG_ASSESSMENT_OK)) {
 674                                 // previously added by user
 675                                 cfadd(result, "{%O=#T}", kSecAssessmentAssessmentVerdict);
 676                                 addAuthority(flags, result, "Prior Assessment");
 677                         } else if (!overrideAssessment(flags)) {                // no need to do more work if we're off
 678                                 try {
 679                                         evaluateCode(path, kAuthorityOpenDoc, flags, context, result, true);
 680                                 } catch (...) {
 681                                         // some documents can't be code signed, so this may be quite benign
 682                                 }
 683                         }
 684                         if (CFDictionaryGetValue(result, kSecAssessmentAssessmentVerdict) == NULL) {    // no code signature to help us out
 685                            cfadd(result, "{%O=#F}", kSecAssessmentAssessmentVerdict);
 686                            addAuthority(flags, result, "_XProtect");
 687                         }
 688                         addToAuthority(result, kLSDownloadRiskCategoryKey, riskCategory);
 689                         return;
 690                 }
 691         }
 692         // insufficient information from LS - deny by default
 693         cfadd(result, "{%O=#F}", kSecAssessmentAssessmentVerdict);
 694         addAuthority(flags, result, "Insufficient Context");
 695 }
 696
 697
 698 //
 699 // Result-creation helpers
 700 //
 701 void PolicyEngine::addAuthority(SecAssessmentFlags flags, CFMutableDictionaryRef parent, const char *label, SQLite::int64 row, CFTypeRef cacheInfo, bool weak, uint64_t ruleFlags)
 702 {
 703         CFRef<CFMutableDictionaryRef> auth = makeCFMutableDictionary();
 704         if (label && label[0])
 705                 cfadd(auth, "{%O=%s}", kSecAssessmentAssessmentSource, label);
 706         if (row)
 707                 CFDictionaryAddValue(auth, kSecAssessmentAssessmentAuthorityRow, CFTempNumber(row));
 708         if (overrideAssessment(flags))
 709                 CFDictionaryAddValue(auth, kSecAssessmentAssessmentAuthorityOverride, kDisabledOverride);
 710         if (cacheInfo)
 711                 CFDictionaryAddValue(auth, kSecAssessmentAssessmentFromCache, cacheInfo);
 712         CFDictionaryAddValue(auth, kSecAssessmentAssessmentAuthorityFlags, CFTempNumber(ruleFlags));
 713         if (weak) {
 714                 CFDictionaryAddValue(auth, kSecAssessmentAssessmentWeakSignature, kCFBooleanTrue);
 715                 CFDictionaryReplaceValue(parent, kSecAssessmentAssessmentAuthority, auth);
 716         } else {
 717                 CFDictionaryAddValue(parent, kSecAssessmentAssessmentAuthority, auth);
 718         }
 719 }
 720
 721 void PolicyEngine::addToAuthority(CFMutableDictionaryRef parent, CFStringRef key, CFTypeRef value)
 722 {
 723         CFMutableDictionaryRef authority = CFMutableDictionaryRef(CFDictionaryGetValue(parent, kSecAssessmentAssessmentAuthority));
 724         assert(authority);
 725         CFDictionaryAddValue(authority, key, value);
 726 }
 727
 728
 729 //
 730 // Add a rule to the policy database
 731 //
 732 CFDictionaryRef PolicyEngine::add(CFTypeRef inTarget, AuthorityType type, SecAssessmentFlags flags, CFDictionaryRef context)
 733 {
 734         // default type to execution
 735         if (type == kAuthorityInvalid)
 736                 type = kAuthorityExecute;
 737
 738         authorizeUpdate(flags, context);
 739         CFDictionary ctx(context, errSecCSInvalidAttributeValues);
 740         CFCopyRef<CFTypeRef> target = inTarget;
 741         CFRef<CFDataRef> bookmark = NULL;
 742         std::string filter_unsigned;
 743
 744         switch (type) {
 745         case kAuthorityExecute:
 746                 normalizeTarget(target, type, ctx, &filter_unsigned);
 747                 // bookmarks are untrusted and just a hint to callers
 748                 bookmark = ctx.get<CFDataRef>(kSecAssessmentRuleKeyBookmark);
 749                 break;
 750         case kAuthorityInstall:
 751                 if (inTarget && CFGetTypeID(inTarget) == CFURLGetTypeID()) {
 752                         // no good way to turn an installer file into a requirement. Pretend to succeeed so caller proceeds
 753                         CFRef<CFArrayRef> properties = makeCFArray(2, kCFURLFileResourceIdentifierKey, kCFURLContentModificationDateKey);
 754                         CFRef<CFErrorRef> error;
 755                         CFURLBookmarkCreationOptions options = kCFURLBookmarkCreationDoNotIncludeSandboxExtensionsMask | kCFURLBookmarkCreationMinimalBookmarkMask;
 756                         if (CFRef<CFDataRef> bookmark = CFURLCreateBookmarkData(NULL, CFURLRef(inTarget), options, properties, NULL, &error.aref())) {
 757                                 UnixPlusPlus::AutoFileDesc fd(lastApprovedFile, O_WRONLY | O_CREAT | O_TRUNC);
 758                                 fd.write(CFDataGetBytePtr(bookmark), CFDataGetLength(bookmark));
 759                                 return NULL;
 760                         }
 761                 }
 762                 break;
 763         case kAuthorityOpenDoc:
 764                 // handle document-open differently: use quarantine flags for whitelisting
 765                 if (!target || CFGetTypeID(target) != CFURLGetTypeID()) // can only "add" file paths
 766                         MacOSError::throwMe(errSecCSInvalidObjectRef);
 767                 try {
 768                         std::string spath = cfString(target.as<CFURLRef>());
 769                         FileQuarantine qtn(spath.c_str());
 770                         qtn.setFlag(QTN_FLAG_ASSESSMENT_OK);
 771                         qtn.applyTo(spath.c_str());
 772                 } catch (const CommonError &error) {
 773                         // could not set quarantine flag - report qualified success
 774                         return cfmake<CFDictionaryRef>("{%O=%O,'assessment:error'=%d}",
 775                                 kSecAssessmentAssessmentAuthorityOverride, CFSTR("error setting quarantine"), error.osStatus());
 776                 } catch (...) {
 777                         return cfmake<CFDictionaryRef>("{%O=%O}", kSecAssessmentAssessmentAuthorityOverride, CFSTR("unable to set quarantine"));
 778                 }
 779                 return NULL;
 780         }
 781
 782         // if we now have anything else, we're busted
 783         if (!target || CFGetTypeID(target) != SecRequirementGetTypeID())
 784                 MacOSError::throwMe(errSecCSInvalidObjectRef);
 785
 786         double priority = 0;
 787         string label;
 788         bool allow = true;
 789         double expires = never;
 790         string remarks;
 791         SQLite::uint64 dbFlags = kAuthorityFlagWhitelistV2 | kAuthorityFlagWhitelistSHA256;
 792
 793         if (CFNumberRef pri = ctx.get<CFNumberRef>(kSecAssessmentUpdateKeyPriority))
 794                 CFNumberGetValue(pri, kCFNumberDoubleType, &priority);
 795         if (CFStringRef lab = ctx.get<CFStringRef>(kSecAssessmentUpdateKeyLabel))
 796                 label = cfString(lab);
 797         if (CFDateRef time = ctx.get<CFDateRef>(kSecAssessmentUpdateKeyExpires))
 798                 // we're using Julian dates here; convert from CFDate
 799                 expires = dateToJulian(time);
 800         if (CFBooleanRef allowing = ctx.get<CFBooleanRef>(kSecAssessmentUpdateKeyAllow))
 801                 allow = allowing == kCFBooleanTrue;
 802         if (CFStringRef rem = ctx.get<CFStringRef>(kSecAssessmentUpdateKeyRemarks))
 803                 remarks = cfString(rem);
 804
 805         CFRef<CFStringRef> requirementText;
 806         MacOSError::check(SecRequirementCopyString(target.as<SecRequirementRef>(), kSecCSDefaultFlags, &requirementText.aref()));
 807         SQLite::Transaction xact(*this, SQLite3::Transaction::deferred, "add_rule");
 808         SQLite::Statement insert(*this,
 809                 "INSERT INTO authority (type, allow, requirement, priority, label, expires, filter_unsigned, remarks, flags)"
 810                 "       VALUES (:type, :allow, :requirement, :priority, :label, :expires, :filter_unsigned, :remarks, :flags);");
 811         insert.bind(":type").integer(type);
 812         insert.bind(":allow").integer(allow);
 813         insert.bind(":requirement") = requirementText.get();
 814         insert.bind(":priority") = priority;
 815         if (!label.empty())
 816                 insert.bind(":label") = label;
 817         insert.bind(":expires") = expires;
 818         insert.bind(":filter_unsigned") = filter_unsigned.empty() ? NULL : filter_unsigned.c_str();
 819         if (!remarks.empty())
 820                 insert.bind(":remarks") = remarks;
 821         insert.bind(":flags").integer(dbFlags);
 822         insert.execute();
 823         SQLite::int64 newRow = this->lastInsert();
 824         if (bookmark) {
 825                 SQLite::Statement bi(*this, "INSERT INTO bookmarkhints (bookmark, authority) VALUES (:bookmark, :authority)");
 826                 bi.bind(":bookmark") = CFDataRef(bookmark);
 827                 bi.bind(":authority").integer(newRow);
 828                 bi.execute();
 829         }
 830         this->purgeObjects(priority);
 831         xact.commit();
 832         notify_post(kNotifySecAssessmentUpdate);
 833         return cfmake<CFDictionaryRef>("{%O=%d}", kSecAssessmentUpdateKeyRow, newRow);
 834 }
 835
 836
 837 CFDictionaryRef PolicyEngine::remove(CFTypeRef target, AuthorityType type, SecAssessmentFlags flags, CFDictionaryRef context)
 838 {
 839         if (type == kAuthorityOpenDoc) {
 840                 // handle document-open differently: use quarantine flags for whitelisting
 841                 authorizeUpdate(flags, context);
 842                 if (!target || CFGetTypeID(target) != CFURLGetTypeID())
 843                         MacOSError::throwMe(errSecCSInvalidObjectRef);
 844                 std::string spath = cfString(CFURLRef(target)).c_str();
 845                 FileQuarantine qtn(spath.c_str());
 846                 qtn.clearFlag(QTN_FLAG_ASSESSMENT_OK);
 847                 qtn.applyTo(spath.c_str());
 848                 return NULL;
 849         }
 850         return manipulateRules("DELETE FROM authority", target, type, flags, context, true);
 851 }
 852
 853 CFDictionaryRef PolicyEngine::enable(CFTypeRef target, AuthorityType type, SecAssessmentFlags flags, CFDictionaryRef context, bool authorize)
 854 {
 855         return manipulateRules("UPDATE authority SET disabled = 0", target, type, flags, context, authorize);
 856 }
 857
 858 CFDictionaryRef PolicyEngine::disable(CFTypeRef target, AuthorityType type, SecAssessmentFlags flags, CFDictionaryRef context, bool authorize)
 859 {
 860         return manipulateRules("UPDATE authority SET disabled = 1", target, type, flags, context, authorize);
 861 }
 862
 863 CFDictionaryRef PolicyEngine::find(CFTypeRef target, AuthorityType type, SecAssessmentFlags flags, CFDictionaryRef context)
 864 {
 865     //for privacy reasons we only want to allow the admin to list the database
 866     authorizeUpdate(flags, context);
 867
 868         SQLite::Statement query(*this);
 869         selectRules(query, "SELECT scan_authority.id, scan_authority.type, scan_authority.requirement, scan_authority.allow, scan_authority.label, scan_authority.priority, scan_authority.remarks, scan_authority.expires, scan_authority.disabled, bookmarkhints.bookmark FROM scan_authority LEFT OUTER JOIN bookmarkhints ON scan_authority.id = bookmarkhints.authority",
 870                 "scan_authority", target, type, flags, context,
 871                 " ORDER BY priority DESC");
 872         CFRef<CFMutableArrayRef> found = makeCFMutableArray(0);
 873         while (query.nextRow()) {
 874                 SQLite::int64 id = query[0];
 875                 int type = int(query[1]);
 876                 const char *requirement = query[2];
 877                 int allow = int(query[3]);
 878                 const char *label = query[4];
 879                 double priority = query[5];
 880                 const char *remarks = query[6];
 881                 double expires = query[7];
 882                 int disabled = int(query[8]);
 883                 CFRef<CFDataRef> bookmark = query[9].data();
 884                 CFRef<CFMutableDictionaryRef> rule = makeCFMutableDictionary(5,
 885                         kSecAssessmentRuleKeyID, CFTempNumber(id).get(),
 886                         kSecAssessmentRuleKeyType, CFRef<CFStringRef>(typeNameFor(type)).get(),
 887                         kSecAssessmentRuleKeyRequirement, CFTempString(requirement).get(),
 888                         kSecAssessmentRuleKeyAllow, allow ? kCFBooleanTrue : kCFBooleanFalse,
 889                         kSecAssessmentRuleKeyPriority, CFTempNumber(priority).get()
 890                         );
 891                 if (label)
 892                         CFDictionaryAddValue(rule, kSecAssessmentRuleKeyLabel, CFTempString(label));
 893                 if (remarks)
 894                         CFDictionaryAddValue(rule, kSecAssessmentRuleKeyRemarks, CFTempString(remarks));
 895                 if (expires != never)
 896                         CFDictionaryAddValue(rule, kSecAssessmentRuleKeyExpires, CFRef<CFDateRef>(julianToDate(expires)));
 897                 if (disabled)
 898                         CFDictionaryAddValue(rule, kSecAssessmentRuleKeyDisabled, CFTempNumber(disabled));
 899                 if (bookmark)
 900                         CFDictionaryAddValue(rule, kSecAssessmentRuleKeyBookmark, bookmark);
 901                 CFArrayAppendValue(found, rule);
 902         }
 903         if (CFArrayGetCount(found) == 0)
 904                 MacOSError::throwMe(errSecCSNoMatches);
 905         return cfmake<CFDictionaryRef>("{%O=%O}", kSecAssessmentUpdateKeyFound, found.get());
 906 }
 907
 908
 909 CFDictionaryRef PolicyEngine::update(CFTypeRef target, SecAssessmentFlags flags, CFDictionaryRef context)
 910 {
 911         // update GKE
 912         installExplicitSet(gkeAuthFile, gkeSigsFile);
 913
 914         AuthorityType type = typeFor(context, kAuthorityInvalid);
 915         CFStringRef edit = CFStringRef(CFDictionaryGetValue(context, kSecAssessmentContextKeyUpdate));
 916         CFDictionaryRef result;
 917         if (CFEqual(edit, kSecAssessmentUpdateOperationAdd))
 918                 result = this->add(target, type, flags, context);
 919         else if (CFEqual(edit, kSecAssessmentUpdateOperationRemove))
 920                 result = this->remove(target, type, flags, context);
 921         else if (CFEqual(edit, kSecAssessmentUpdateOperationEnable))
 922                 result = this->enable(target, type, flags, context, true);
 923         else if (CFEqual(edit, kSecAssessmentUpdateOperationDisable))
 924                 result = this->disable(target, type, flags, context, true);
 925         else if (CFEqual(edit, kSecAssessmentUpdateOperationFind))
 926                 result = this->find(target, type, flags, context);
 927         else
 928                 MacOSError::throwMe(errSecCSInvalidAttributeValues);
 929         if (result == NULL)
 930                 result = makeCFDictionary(0);           // success, no details
 931         return result;
 932 }
 933
 934
 935 //
 936 // Construct and prepare an SQL query on the authority table, operating on some set of existing authority records.
 937 // In essence, this appends a suitable WHERE clause to the stanza passed and prepares it on the statement given.
 938 //
 939 void PolicyEngine::selectRules(SQLite::Statement &action, std::string phrase, std::string table,
 940         CFTypeRef inTarget, AuthorityType type, SecAssessmentFlags flags, CFDictionaryRef context, std::string suffix /* = "" */)
 941 {
 942         CFDictionary ctx(context, errSecCSInvalidAttributeValues);
 943         CFCopyRef<CFTypeRef> target = inTarget;
 944         std::string filter_unsigned;    // ignored; used just to trigger ad-hoc signing
 945         normalizeTarget(target, type, ctx, &filter_unsigned);
 946
 947         string label;
 948         if (CFStringRef lab = ctx.get<CFStringRef>(kSecAssessmentUpdateKeyLabel))
 949                 label = cfString(CFStringRef(lab));
 950
 951         if (!target) {
 952                 if (label.empty()) {
 953                         if (type == kAuthorityInvalid) {
 954                                 action.query(phrase + suffix);
 955                         } else {
 956                                 action.query(phrase + " WHERE " + table + ".type = :type" + suffix);
 957                                 action.bind(":type").integer(type);
 958                         }
 959                 } else {        // have label
 960                         if (type == kAuthorityInvalid) {
 961                                 action.query(phrase + " WHERE " + table + ".label = :label" + suffix);
 962                         } else {
 963                                 action.query(phrase + " WHERE " + table + ".type = :type AND " + table + ".label = :label" + suffix);
 964                                 action.bind(":type").integer(type);
 965                         }
 966                         action.bind(":label") = label;
 967                 }
 968         } else if (CFGetTypeID(target) == CFNumberGetTypeID()) {
 969                 action.query(phrase + " WHERE " + table + ".id = :id" + suffix);
 970                 action.bind(":id").integer(cfNumber<uint64_t>(target.as<CFNumberRef>()));
 971         } else if (CFGetTypeID(target) == SecRequirementGetTypeID()) {
 972                 if (type == kAuthorityInvalid)
 973                         type = kAuthorityExecute;
 974                 CFRef<CFStringRef> requirementText;
 975                 MacOSError::check(SecRequirementCopyString(target.as<SecRequirementRef>(), kSecCSDefaultFlags, &requirementText.aref()));
 976                 action.query(phrase + " WHERE " + table + ".type = :type AND " + table + ".requirement = :requirement" + suffix);
 977                 action.bind(":type").integer(type);
 978                 action.bind(":requirement") = requirementText.get();
 979         } else
 980                 MacOSError::throwMe(errSecCSInvalidObjectRef);
 981 }
 982
 983
 984 //
 985 // Execute an atomic change to existing records in the authority table.
 986 //
 987 CFDictionaryRef PolicyEngine::manipulateRules(const std::string &stanza,
 988         CFTypeRef inTarget, AuthorityType type, SecAssessmentFlags flags, CFDictionaryRef context, bool authorize)
 989 {
 990         SQLite::Transaction xact(*this, SQLite3::Transaction::deferred, "rule_change");
 991         SQLite::Statement action(*this);
 992         if (authorize)
 993                 authorizeUpdate(flags, context);
 994         selectRules(action, stanza, "authority", inTarget, type, flags, context);
 995         action.execute();
 996         unsigned int changes = this->changes(); // latch change count
 997         // We MUST purge objects with priority <= MAX(priority of any changed rules);
 998         // but for now we just get lazy and purge them ALL.
 999         if (changes) {
1000                 this->purgeObjects(1.0E100);
1001                 xact.commit();
1002                 notify_post(kNotifySecAssessmentUpdate);
1003                 return cfmake<CFDictionaryRef>("{%O=%d}", kSecAssessmentUpdateKeyCount, changes);
1004         }
1005         // no change; return an error
1006         MacOSError::throwMe(errSecCSNoMatches);
1007 }
1008
1009
1010 //
1011 // Fill in extra information about the originator of cryptographic credentials found - if any
1012 //
1013 void PolicyEngine::setOrigin(CFArrayRef chain, CFMutableDictionaryRef result)
1014 {
1015         if (chain)
1016                 if (CFArrayGetCount(chain) > 0)
1017                         if (SecCertificateRef leaf = SecCertificateRef(CFArrayGetValueAtIndex(chain, 0)))
1018                                 if (CFStringRef summary = SecCertificateCopyLongDescription(NULL, leaf, NULL)) {
1019                                         CFDictionarySetValue(result, kSecAssessmentAssessmentOriginator, summary);
1020                                         CFRelease(summary);
1021                                 }
1022 }
1023
1024
1025 //
1026 // Take an assessment outcome and record it in the object cache
1027 //
1028 void PolicyEngine::recordOutcome(SecStaticCodeRef code, bool allow, AuthorityType type, double expires, SQLite::int64 authority)
1029 {
1030         CFRef<CFDictionaryRef> info;
1031         MacOSError::check(SecCodeCopySigningInformation(code, kSecCSDefaultFlags, &info.aref()));
1032         CFDataRef cdHash = CFDataRef(CFDictionaryGetValue(info, kSecCodeInfoUnique));
1033         assert(cdHash);         // was signed
1034         CFRef<CFURLRef> path;
1035         MacOSError::check(SecCodeCopyPath(code, kSecCSDefaultFlags, &path.aref()));
1036         assert(expires);
1037         SQLite::Transaction xact(*this, SQLite3::Transaction::deferred, "caching");
1038         SQLite::Statement insert(*this,
1039                 "INSERT OR REPLACE INTO object (type, allow, hash, expires, path, authority)"
1040                 "       VALUES (:type, :allow, :hash, :expires, :path,"
1041                 "       CASE :authority WHEN 0 THEN (SELECT id FROM authority WHERE label = 'No Matching Rule') ELSE :authority END"
1042                 "       );");
1043         insert.bind(":type").integer(type);
1044         insert.bind(":allow").integer(allow);
1045         insert.bind(":hash") = cdHash;
1046         insert.bind(":expires") = expires;
1047         insert.bind(":path") = cfString(path);
1048         insert.bind(":authority").integer(authority);
1049         insert.execute();
1050         xact.commit();
1051 }
1052
1053
1054 //
1055 // Record a UI failure record after proper validation of the caller
1056 //
1057 void PolicyEngine::recordFailure(CFDictionaryRef info)
1058 {
1059         CFRef<CFDataRef> infoData = makeCFData(info);
1060         UnixPlusPlus::AutoFileDesc fd(lastRejectFile, O_WRONLY | O_CREAT | O_TRUNC);
1061         fd.write(CFDataGetBytePtr(infoData), CFDataGetLength(infoData));
1062         notify_post(kNotifySecAssessmentRecordingChange);
1063 }
1064
1065
1066 //
1067 // Perform update authorization processing.
1068 // Throws an exception if authorization is denied.
1069 //
1070 static void authorizeUpdate(SecAssessmentFlags flags, CFDictionaryRef context)
1071 {
1072         AuthorizationRef authorization = NULL;
1073
1074         if (context)
1075                 if (CFTypeRef authkey = CFDictionaryGetValue(context, kSecAssessmentUpdateKeyAuthorization))
1076                         if (CFGetTypeID(authkey) == CFDataGetTypeID()) {
1077                                 CFDataRef authdata = CFDataRef(authkey);
1078                                 if (CFDataGetLength(authdata) != sizeof(AuthorizationExternalForm))
1079                                         MacOSError::throwMe(errSecCSInvalidObjectRef);
1080                                 MacOSError::check(AuthorizationCreateFromExternalForm((AuthorizationExternalForm *)CFDataGetBytePtr(authdata), &authorization));
1081                         }
1082         if (authorization == NULL)
1083                 MacOSError::throwMe(errSecCSDBDenied);
1084
1085         AuthorizationItem right[] = {
1086                 { "com.apple.security.assessment.update", 0, NULL, 0 }
1087         };
1088         AuthorizationRights rights = { sizeof(right) / sizeof(right[0]), right };
1089         MacOSError::check(AuthorizationCopyRights(authorization, &rights, NULL,
1090                 kAuthorizationFlagExtendRights | kAuthorizationFlagInteractionAllowed, NULL));
1091
1092         MacOSError::check(AuthorizationFree(authorization, kAuthorizationFlagDefaults));
1093 }
1094
1095
1096 //
1097 // Perform common argument normalizations for update operations
1098 //
1099 void PolicyEngine::normalizeTarget(CFRef<CFTypeRef> &target, AuthorityType type, CFDictionary &context, std::string *signUnsigned)
1100 {
1101         // turn CFURLs into (designated) SecRequirements
1102         if (target && CFGetTypeID(target) == CFURLGetTypeID()) {
1103                 CFRef<SecStaticCodeRef> code;
1104                 CFURLRef path = target.as<CFURLRef>();
1105                 MacOSError::check(SecStaticCodeCreateWithPath(path, kSecCSDefaultFlags, &code.aref()));
1106                 switch (OSStatus rc = SecCodeCopyDesignatedRequirement(code, kSecCSDefaultFlags, (SecRequirementRef *)&target.aref())) {
1107                 case errSecSuccess: {
1108                         // use the *default* DR to avoid unreasonably wide DRs opening up Gatekeeper to attack
1109                         CFRef<CFDictionaryRef> info;
1110                         MacOSError::check(SecCodeCopySigningInformation(code, kSecCSRequirementInformation, &info.aref()));
1111                         target = CFDictionaryGetValue(info, kSecCodeInfoImplicitDesignatedRequirement);
1112                         }
1113                         break;
1114                 case errSecCSUnsigned:
1115                         if (signUnsigned && temporarySigning(code, type, path, kAuthorityFlagWhitelistV2 | kAuthorityFlagWhitelistSHA256)) {    // ad-hoc sign the code temporarily
1116                                 MacOSError::check(SecCodeCopyDesignatedRequirement(code, kSecCSDefaultFlags, (SecRequirementRef *)&target.aref()));
1117                                 *signUnsigned = createWhitelistScreen(code);
1118                                 break;
1119                         }
1120                         MacOSError::check(rc);
1121                 case errSecCSSignatureFailed:
1122                         // recover certain cases of broken signatures (well, try)
1123                         if (codeInvalidityExceptions(code, NULL)) {
1124                                 // Ad-hoc sign the code in place (requiring a writable subject). This requires root privileges.
1125                                 CFRef<SecCodeSignerRef> signer;
1126                                 CFTemp<CFDictionaryRef> arguments("{%O=#N}", kSecCodeSignerIdentity);
1127                                 MacOSError::check(SecCodeSignerCreate(arguments, kSecCSSignOpaque, &signer.aref()));
1128                                 MacOSError::check(SecCodeSignerAddSignature(signer, code, kSecCSDefaultFlags));
1129                                 MacOSError::check(SecCodeCopyDesignatedRequirement(code, kSecCSDefaultFlags, (SecRequirementRef *)&target.aref()));
1130                                 break;
1131                         }
1132                         MacOSError::check(rc);
1133                 default:
1134                         MacOSError::check(rc);
1135                 }
1136                 if (context.get(kSecAssessmentUpdateKeyRemarks) == NULL)        {
1137                         // no explicit remarks; add one with the path
1138                         CFRef<CFURLRef> path;
1139                         MacOSError::check(SecCodeCopyPath(code, kSecCSDefaultFlags, &path.aref()));
1140                         CFMutableDictionaryRef dict = makeCFMutableDictionary(context.get());
1141                         CFDictionaryAddValue(dict, kSecAssessmentUpdateKeyRemarks, CFTempString(cfString(path)));
1142                         context.take(dict);
1143                 }
1144                 CFStringRef edit = CFStringRef(context.get(kSecAssessmentContextKeyUpdate));
1145                 if (type == kAuthorityExecute && CFEqual(edit, kSecAssessmentUpdateOperationAdd)) {
1146                         // implicitly whitelist the code
1147                         mOpaqueWhitelist.add(code);
1148                 }
1149         }
1150 }
1151
1152
1153 //
1154 // Process special overrides for invalidly signed code.
1155 // This is the (hopefully minimal) concessions we make to keep hurting our customers
1156 // for our own prior mistakes...
1157 //
1158 static bool codeInvalidityExceptions(SecStaticCodeRef code, CFMutableDictionaryRef result)
1159 {
1160         CFRef<CFDictionaryRef> info;
1161         MacOSError::check(SecCodeCopySigningInformation(code, kSecCSDefaultFlags, &info.aref()));
1162         if (CFURLRef executable = CFURLRef(CFDictionaryGetValue(info, kSecCodeInfoMainExecutable))) {
1163                 SInt32 error;
1164                 if (OSAIsRecognizedExecutableURL(executable, &error)) {
1165                         if (result)
1166                                 CFDictionaryAddValue(result,
1167                                         kSecAssessmentAssessmentAuthorityOverride, CFSTR("ignoring known invalid applet signature"));
1168                         return true;
1169                 }
1170         }
1171         return false;
1172 }
1173
1174
1175 } // end namespace CodeSigning
1176 } // end namespace Security