OSX/libsecurity_codesigning/lib/policyengine.cpp

   1 /*
   2  * Copyright (c) 2011-2014 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
  19  * limitations under the License.
  20  *
  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->waitForCompletion(evaluationTask, flags, result);
  96     evaluationManager->removeTask(evaluationTask);
  97
  98     // if rejected, reset the automatic rearm timer
  99     if (CFDictionaryGetValue(result, kSecAssessmentAssessmentVerdict) == kCFBooleanFalse)
 100         resetRearmTimer("reject");
 101 }
 102
 103
 104 static std::string createWhitelistScreen(char type, SHA1 &hash)
 105 {
 106         SHA1::Digest digest;
 107         hash.finish(digest);
 108         char buffer[2*SHA1::digestLength + 2] = { type };
 109         for (size_t n = 0; n < SHA1::digestLength; n++)
 110                 sprintf(buffer + 1 + 2*n, "%02.2x", digest[n]);
 111         return buffer;
 112 }
 113
 114
 115 void PolicyEngine::evaluateCodeItem(SecStaticCodeRef code, CFURLRef path, AuthorityType type, SecAssessmentFlags flags, bool nested, CFMutableDictionaryRef result)
 116 {
 117
 118         SQLite::Statement query(*this,
 119                 "SELECT allow, requirement, id, label, expires, flags, disabled, filter_unsigned, remarks FROM scan_authority"
 120                 " WHERE type = :type"
 121                 " ORDER BY priority DESC;");
 122         query.bind(":type").integer(type);
 123
 124         SQLite3::int64 latentID = 0;            // first (highest priority) disabled matching ID
 125         std::string latentLabel;                        // ... and associated label, if any
 126
 127         while (query.nextRow()) {
 128                 bool allow = int(query[0]);
 129                 const char *reqString = query[1];
 130                 SQLite3::int64 id = query[2];
 131                 const char *label = query[3];
 132                 double expires = query[4];
 133                 sqlite3_int64 ruleFlags = query[5];
 134                 SQLite3::int64 disabled = query[6];
 135 //              const char *filter = query[7];
 136 //              const char *remarks = query[8];
 137
 138                 CFRef<SecRequirementRef> requirement;
 139                 MacOSError::check(SecRequirementCreateWithString(CFTempString(reqString), kSecCSDefaultFlags, &requirement.aref()));
 140                 switch (OSStatus rc = SecStaticCodeCheckValidity(code, kSecCSBasicValidateOnly | kSecCSCheckGatekeeperArchitectures, requirement)) {
 141                 case errSecSuccess:
 142                         break;                                          // rule match; process below
 143                 case errSecCSReqFailed:
 144                         continue;                                       // rule does not apply
 145                 case errSecCSVetoed:
 146                         return;                                         // nested code has failed to pass
 147                 default:
 148                         MacOSError::throwMe(rc);        // general error; pass to caller
 149                 }
 150
 151                 // if this rule is disabled, skip it but record the first matching one for posterity
 152                 if (disabled && latentID == 0) {
 153                         latentID = id;
 154                         latentLabel = label ? label : "";
 155                         continue;
 156                 }
 157
 158                 // current rule is first rule (in priority order) that matched. Apply it
 159                 if (nested)     // success, nothing to record
 160                         return;
 161
 162                 CFRef<CFDictionaryRef> info;    // as needed
 163                 if (flags & kSecAssessmentFlagRequestOrigin) {
 164                         if (!info)
 165                                 MacOSError::check(SecCodeCopySigningInformation(code, kSecCSSigningInformation, &info.aref()));
 166                         if (CFArrayRef chain = CFArrayRef(CFDictionaryGetValue(info, kSecCodeInfoCertificates)))
 167                                 setOrigin(chain, result);
 168                 }
 169                 if (!(ruleFlags & kAuthorityFlagInhibitCache) && !(flags & kSecAssessmentFlagNoCache)) {        // cache inhibit
 170                         if (!info)
 171                                 MacOSError::check(SecCodeCopySigningInformation(code, kSecCSSigningInformation, &info.aref()));
 172                         if (SecTrustRef trust = SecTrustRef(CFDictionaryGetValue(info, kSecCodeInfoTrust))) {
 173                                 CFRef<CFDictionaryRef> xinfo;
 174                                 MacOSError::check(SecTrustCopyExtendedResult(trust, &xinfo.aref()));
 175                                 if (CFDateRef limit = CFDateRef(CFDictionaryGetValue(xinfo, kSecTrustExpirationDate))) {
 176                                         this->recordOutcome(code, allow, type, min(expires, dateToJulian(limit)), id);
 177                                 }
 178                         }
 179                 }
 180                 if (allow) {
 181                         if (SYSPOLICY_ASSESS_OUTCOME_ACCEPT_ENABLED()) {
 182                                 if (!info)
 183                                         MacOSError::check(SecCodeCopySigningInformation(code, kSecCSSigningInformation, &info.aref()));
 184                                 CFDataRef cdhash = CFDataRef(CFDictionaryGetValue(info, kSecCodeInfoUnique));
 185                                 SYSPOLICY_ASSESS_OUTCOME_ACCEPT(cfString(path).c_str(), type, label, cdhash ? CFDataGetBytePtr(cdhash) : NULL);
 186                         }
 187                 } else {
 188                         if (SYSPOLICY_ASSESS_OUTCOME_DENY_ENABLED() || SYSPOLICY_RECORDER_MODE_ENABLED()) {
 189                                 if (!info)
 190                                         MacOSError::check(SecCodeCopySigningInformation(code, kSecCSSigningInformation, &info.aref()));
 191                                 CFDataRef cdhash = CFDataRef(CFDictionaryGetValue(info, kSecCodeInfoUnique));
 192                                 std::string cpath = cfString(path);
 193                                 const void *hashp = cdhash ? CFDataGetBytePtr(cdhash) : NULL;
 194                                 SYSPOLICY_ASSESS_OUTCOME_DENY(cpath.c_str(), type, label, hashp);
 195                                 SYSPOLICY_RECORDER_MODE(cpath.c_str(), type, label, hashp, recorder_code_untrusted);
 196                         }
 197                 }
 198                 cfadd(result, "{%O=%B}", kSecAssessmentAssessmentVerdict, allow);
 199                 addAuthority(flags, result, label, id);
 200                 return;
 201         }
 202
 203         // no applicable authority (but signed, perhaps temporarily). Deny by default
 204         CFRef<CFDictionaryRef> info;
 205         MacOSError::check(SecCodeCopySigningInformation(code, kSecCSSigningInformation, &info.aref()));
 206         if (flags & kSecAssessmentFlagRequestOrigin) {
 207                 if (CFArrayRef chain = CFArrayRef(CFDictionaryGetValue(info, kSecCodeInfoCertificates)))
 208                         setOrigin(chain, result);
 209         }
 210         if (SYSPOLICY_ASSESS_OUTCOME_DEFAULT_ENABLED() || SYSPOLICY_RECORDER_MODE_ENABLED()) {
 211                 CFDataRef cdhash = CFDataRef(CFDictionaryGetValue(info, kSecCodeInfoUnique));
 212                 const void *hashp = cdhash ? CFDataGetBytePtr(cdhash) : NULL;
 213                 std::string cpath = cfString(path);
 214                 SYSPOLICY_ASSESS_OUTCOME_DEFAULT(cpath.c_str(), type, latentLabel.c_str(), hashp);
 215                 SYSPOLICY_RECORDER_MODE(cpath.c_str(), type, latentLabel.c_str(), hashp, 0);
 216         }
 217         if (!(flags & kSecAssessmentFlagNoCache))
 218                 this->recordOutcome(code, false, type, this->julianNow() + NEGATIVE_HOLD, latentID);
 219         cfadd(result, "{%O=%B}", kSecAssessmentAssessmentVerdict, false);
 220         addAuthority(flags, result, latentLabel.c_str(), latentID);
 221 }
 222
 223
 224 void PolicyEngine::adjustValidation(SecStaticCodeRef code)
 225 {
 226         CFRef<CFDictionaryRef> conditions = mOpaqueWhitelist.validationConditionsFor(code);
 227         SecStaticCodeSetValidationConditions(code, conditions);
 228 }
 229
 230
 231 bool PolicyEngine::temporarySigning(SecStaticCodeRef code, AuthorityType type, CFURLRef path, SecAssessmentFlags matchFlags)
 232 {
 233         if (matchFlags == 0) {  // playback; consult authority table for matches
 234                 DiskRep *rep = SecStaticCode::requiredStatic(code)->diskRep();
 235                 std::string screen;
 236                 if (CFRef<CFDataRef> info = rep->component(cdInfoSlot)) {
 237                         SHA1 hash;
 238                         hash.update(CFDataGetBytePtr(info), CFDataGetLength(info));
 239                         screen = createWhitelistScreen('I', hash);
 240                 } else if (rep->mainExecutableImage()) {
 241                         screen = "N";
 242                 } else {
 243                         SHA1 hash;
 244                         hashFileData(rep->mainExecutablePath().c_str(), &hash);
 245                         screen = createWhitelistScreen('M', hash);
 246                 }
 247                 SQLite::Statement query(*this,
 248                         "SELECT flags FROM authority "
 249                         "WHERE type = :type"
 250                         " AND NOT flags & :flag"
 251                         " AND CASE WHEN filter_unsigned IS NULL THEN remarks = :remarks ELSE filter_unsigned = :screen END");
 252                 query.bind(":type").integer(type);
 253                 query.bind(":flag").integer(kAuthorityFlagDefault);
 254                 query.bind(":screen") = screen;
 255                 query.bind(":remarks") = cfString(path);
 256                 if (!query.nextRow())   // guaranteed no matching rule
 257                         return false;
 258                 matchFlags = SQLite3::int64(query[0]);
 259         }
 260
 261         try {
 262                 // ad-hoc sign the code and attach the signature
 263                 CFRef<CFDataRef> signature = CFDataCreateMutable(NULL, 0);
 264                 CFTemp<CFDictionaryRef> arguments("{%O=%O, %O=#N}", kSecCodeSignerDetached, signature.get(), kSecCodeSignerIdentity);
 265                 CFRef<SecCodeSignerRef> signer;
 266                 MacOSError::check(SecCodeSignerCreate(arguments, (matchFlags & kAuthorityFlagWhitelistV2) ? kSecCSSignOpaque : kSecCSSignV1, &signer.aref()));
 267                 MacOSError::check(SecCodeSignerAddSignature(signer, code, kSecCSDefaultFlags));
 268                 MacOSError::check(SecCodeSetDetachedSignature(code, signature, kSecCSDefaultFlags));
 269
 270                 SecRequirementRef dr = NULL;
 271                 SecCodeCopyDesignatedRequirement(code, kSecCSDefaultFlags, &dr);
 272                 CFStringRef drs = NULL;
 273                 SecRequirementCopyString(dr, kSecCSDefaultFlags, &drs);
 274
 275                 // if we're in GKE recording mode, save that signature and report its location
 276                 if (SYSPOLICY_RECORDER_MODE_ENABLED()) {
 277                         int status = recorder_code_unable;      // ephemeral signature (not recorded)
 278                         if (geteuid() == 0) {
 279                                 CFRef<CFUUIDRef> uuid = CFUUIDCreate(NULL);
 280                                 std::string sigfile = RECORDER_DIR + cfStringRelease(CFUUIDCreateString(NULL, uuid)) + ".tsig";
 281                                 try {
 282                                         UnixPlusPlus::AutoFileDesc fd(sigfile, O_WRONLY | O_CREAT);
 283                                         fd.write(CFDataGetBytePtr(signature), CFDataGetLength(signature));
 284                                         status = recorder_code_adhoc;   // recorded signature
 285                                         SYSPOLICY_RECORDER_MODE_ADHOC_PATH(cfString(path).c_str(), type, sigfile.c_str());
 286                                 } catch (...) { }
 287                         }
 288
 289                         // now report the D probe itself
 290                         CFRef<CFDictionaryRef> info;
 291                         MacOSError::check(SecCodeCopySigningInformation(code, kSecCSDefaultFlags, &info.aref()));
 292                         CFDataRef cdhash = CFDataRef(CFDictionaryGetValue(info, kSecCodeInfoUnique));
 293                         SYSPOLICY_RECORDER_MODE(cfString(path).c_str(), type, "",
 294                                 cdhash ? CFDataGetBytePtr(cdhash) : NULL, status);
 295                 }
 296
 297                 return true;    // it worked; we're now (well) signed
 298         } catch (...) { }
 299
 300         return false;
 301 }
 302
 303
 304 //
 305 // Executable code.
 306 // Read from disk, evaluate properly, cache as indicated.
 307 //
 308 void PolicyEngine::evaluateCode(CFURLRef path, AuthorityType type, SecAssessmentFlags flags, CFDictionaryRef context, CFMutableDictionaryRef result, bool handleUnsigned)
 309 {
 310         // not really a Gatekeeper function... but reject all "hard quarantined" files because they were made from sandboxed sources without download privilege
 311         FileQuarantine qtn(cfString(path).c_str());
 312         if (qtn.flag(QTN_FLAG_HARD))
 313                 MacOSError::throwMe(errSecCSFileHardQuarantined);
 314
 315         CFCopyRef<SecStaticCodeRef> code;
 316         MacOSError::check(SecStaticCodeCreateWithPath(path, kSecCSDefaultFlags, &code.aref()));
 317
 318         SecCSFlags validationFlags = kSecCSEnforceRevocationChecks | kSecCSCheckAllArchitectures;
 319         if (!(flags & kSecAssessmentFlagAllowWeak))
 320                 validationFlags |= kSecCSStrictValidate;
 321         adjustValidation(code);
 322
 323         // deal with a very special case (broken 10.6/10.7 Applet bundles)
 324         OSStatus rc = SecStaticCodeCheckValidity(code, validationFlags | kSecCSBasicValidateOnly, NULL);
 325         if (rc == errSecCSSignatureFailed) {
 326                 if (!codeInvalidityExceptions(code, result)) {  // invalidly signed, no exceptions -> error
 327                         if (SYSPOLICY_ASSESS_OUTCOME_BROKEN_ENABLED())
 328                                 SYSPOLICY_ASSESS_OUTCOME_BROKEN(cfString(path).c_str(), type, false);
 329                         MacOSError::throwMe(rc);
 330                 }
 331                 // recognized exception - treat as unsigned
 332                 if (SYSPOLICY_ASSESS_OUTCOME_BROKEN_ENABLED())
 333                         SYSPOLICY_ASSESS_OUTCOME_BROKEN(cfString(path).c_str(), type, true);
 334                 rc = errSecCSUnsigned;
 335         }
 336
 337         // ad-hoc sign unsigned code
 338         if (rc == errSecCSUnsigned && handleUnsigned && (!overrideAssessment(flags) || SYSPOLICY_RECORDER_MODE_ENABLED())) {
 339                 if (temporarySigning(code, type, path, 0)) {
 340                         rc = errSecSuccess;             // clear unsigned; we are now well-signed
 341                         validationFlags |= kSecCSBasicValidateOnly;     // no need to re-validate deep contents
 342                 }
 343         }
 344
 345         // prepare for deep traversal of (hopefully) good signatures
 346         SecAssessmentFeedback feedback = SecAssessmentFeedback(CFDictionaryGetValue(context, kSecAssessmentContextKeyFeedback));
 347         MacOSError::check(SecStaticCodeSetCallback(code, kSecCSDefaultFlags, NULL, ^CFTypeRef (SecStaticCodeRef item, CFStringRef cfStage, CFDictionaryRef info) {
 348                 string stage = cfString(cfStage);
 349                 if (stage == "prepared") {
 350                         if (!CFEqual(item, code))       // genuine nested (not top) code
 351                                 adjustValidation(item);
 352                 } else if (stage == "progress") {
 353                         if (feedback && CFEqual(item, code)) {  // top level progress
 354                                 bool proceed = feedback(kSecAssessmentFeedbackProgress, info);
 355                                 if (!proceed)
 356                                         SecStaticCodeCancelValidation(code, kSecCSDefaultFlags);
 357                         }
 358                 } else if (stage == "validated") {
 359                         SecStaticCodeSetCallback(item, kSecCSDefaultFlags, NULL, NULL);         // clear callback to avoid unwanted recursion
 360                         evaluateCodeItem(item, path, type, flags, item != code, result);
 361                         if (CFTypeRef verdict = CFDictionaryGetValue(result, kSecAssessmentAssessmentVerdict))
 362                                 if (CFEqual(verdict, kCFBooleanFalse))
 363                                         return makeCFNumber(OSStatus(errSecCSVetoed));  // (signal nested-code policy failure, picked up below)
 364                 }
 365                 return NULL;
 366         }));
 367
 368         // go for it!
 369         switch (rc = SecStaticCodeCheckValidity(code, validationFlags | kSecCSCheckNestedCode | kSecCSRestrictSymlinks | kSecCSReportProgress, NULL)) {
 370         case errSecSuccess:             // continue below
 371                 break;
 372         case errSecCSUnsigned:
 373                 cfadd(result, "{%O=#F}", kSecAssessmentAssessmentVerdict);
 374                 addAuthority(flags, result, "no usable signature");
 375                 return;
 376         case errSecCSVetoed:            // nested code rejected by rule book; result was filled out there
 377                 return;
 378         case errSecCSWeakResourceRules:
 379         case errSecCSWeakResourceEnvelope:
 380         case errSecCSResourceNotSupported:
 381         case errSecCSAmbiguousBundleFormat:
 382         case errSecCSSignatureNotVerifiable:
 383         case errSecCSRegularFile:
 384         case errSecCSBadMainExecutable:
 385         case errSecCSBadFrameworkVersion:
 386         case errSecCSUnsealedAppRoot:
 387         case errSecCSUnsealedFrameworkRoot:
 388         case errSecCSInvalidSymlink:
 389         {
 390                 // consult the whitelist
 391                 bool allow = false;
 392                 const char *label;
 393                 // we've bypassed evaluateCodeItem before we failed validation. Explicitly apply it now
 394                 SecStaticCodeSetCallback(code, kSecCSDefaultFlags, NULL, NULL);
 395                 evaluateCodeItem(code, path, type, flags | kSecAssessmentFlagNoCache, false, result);
 396                 if (CFTypeRef verdict = CFDictionaryGetValue(result, kSecAssessmentAssessmentVerdict)) {
 397                         // verdict rendered from a nested component - signature not acceptable to Gatekeeper
 398                         if (CFEqual(verdict, kCFBooleanFalse))  // nested code rejected by rule book; result was filled out there
 399                                 return;
 400                         if (CFEqual(verdict, kCFBooleanTrue) && !(flags & kSecAssessmentFlagIgnoreWhitelist))
 401                                 if (mOpaqueWhitelist.contains(code, feedback, rc))
 402                                         allow = true;
 403                 }
 404                 if (allow) {
 405                         label = "allowed cdhash";
 406                 } else {
 407                         CFDictionaryReplaceValue(result, kSecAssessmentAssessmentVerdict, kCFBooleanFalse);
 408                         label = "obsolete resource envelope";
 409                 }
 410                 cfadd(result, "{%O=%d}", kSecAssessmentAssessmentCodeSigningError, rc);
 411                 addAuthority(flags, result, label, 0, NULL, true);
 412                 return;
 413         }
 414         default:
 415                 MacOSError::throwMe(rc);
 416         }
 417 }
 418
 419
 420 //
 421 // Installer archive.
 422 // Hybrid policy: If we detect an installer signature, use and validate that.
 423 // If we don't, check for a code signature instead.
 424 //
 425 void PolicyEngine::evaluateInstall(CFURLRef path, SecAssessmentFlags flags, CFDictionaryRef context, CFMutableDictionaryRef result)
 426 {
 427         const AuthorityType type = kAuthorityInstall;
 428
 429         // check for recent explicit approval, using a bookmark's FileResourceIdentifierKey
 430         if (CFRef<CFDataRef> bookmark = cfLoadFile(lastApprovedFile)) {
 431                 Boolean stale;
 432                 if (CFRef<CFURLRef> url = CFURLCreateByResolvingBookmarkData(NULL, bookmark,
 433                         kCFBookmarkResolutionWithoutUIMask | kCFBookmarkResolutionWithoutMountingMask, NULL, NULL, &stale, NULL))
 434                         if (CFRef<CFDataRef> savedIdent = CFDataRef(CFURLCreateResourcePropertyForKeyFromBookmarkData(NULL, kCFURLFileResourceIdentifierKey, bookmark)))
 435                                 if (CFRef<CFDateRef> savedMod = CFDateRef(CFURLCreateResourcePropertyForKeyFromBookmarkData(NULL, kCFURLContentModificationDateKey, bookmark))) {
 436                                         CFRef<CFDataRef> currentIdent;
 437                                         CFRef<CFDateRef> currentMod;
 438                                         if (CFURLCopyResourcePropertyForKey(path, kCFURLFileResourceIdentifierKey, &currentIdent.aref(), NULL))
 439                                                 if (CFURLCopyResourcePropertyForKey(path, kCFURLContentModificationDateKey, &currentMod.aref(), NULL))
 440                                                         if (CFEqual(savedIdent, currentIdent) && CFEqual(savedMod, currentMod)) {
 441                                                                 cfadd(result, "{%O=#T}", kSecAssessmentAssessmentVerdict);
 442                                                                 addAuthority(flags, result, "explicit preference");
 443                                                                 return;
 444                                                         }
 445                                 }
 446         }
 447
 448         Xar xar(cfString(path).c_str());
 449         if (!xar) {
 450                 // follow the code signing path
 451                 evaluateCode(path, type, flags, context, result, true);
 452                 return;
 453         }
 454
 455         SQLite3::int64 latentID = 0;            // first (highest priority) disabled matching ID
 456         std::string latentLabel;                        // ... and associated label, if any
 457         if (!xar.isSigned()) {
 458                 // unsigned xar
 459                 if (SYSPOLICY_ASSESS_OUTCOME_UNSIGNED_ENABLED())
 460                         SYSPOLICY_ASSESS_OUTCOME_UNSIGNED(cfString(path).c_str(), type);
 461                 cfadd(result, "{%O=#F}", kSecAssessmentAssessmentVerdict);
 462                 addAuthority(flags, result, "no usable signature");
 463                 return;
 464         }
 465         if (CFRef<CFArrayRef> certs = xar.copyCertChain()) {
 466                 CFRef<CFTypeRef> policy = installerPolicy();
 467                 CFRef<SecTrustRef> trust;
 468                 MacOSError::check(SecTrustCreateWithCertificates(certs, policy, &trust.aref()));
 469 //              MacOSError::check(SecTrustSetAnchorCertificates(trust, cfEmptyArray())); // no anchors
 470                 MacOSError::check(SecTrustSetOptions(trust, kSecTrustOptionAllowExpired | kSecTrustOptionImplicitAnchors));
 471
 472                 SecTrustResultType trustResult;
 473                 MacOSError::check(SecTrustEvaluate(trust, &trustResult));
 474                 CFRef<CFArrayRef> chain;
 475                 CSSM_TP_APPLE_EVIDENCE_INFO *info;
 476                 MacOSError::check(SecTrustGetResult(trust, &trustResult, &chain.aref(), &info));
 477
 478                 if (flags & kSecAssessmentFlagRequestOrigin)
 479                         setOrigin(chain, result);
 480
 481                 switch (trustResult) {
 482                 case kSecTrustResultProceed:
 483                 case kSecTrustResultUnspecified:
 484                         break;
 485                 default:
 486                         {
 487                                 OSStatus rc;
 488                                 MacOSError::check(SecTrustGetCssmResultCode(trust, &rc));
 489                                 MacOSError::throwMe(rc);
 490                         }
 491                 }
 492
 493                 SQLite::Statement query(*this,
 494                         "SELECT allow, requirement, id, label, flags, disabled FROM scan_authority"
 495                         " WHERE type = :type"
 496                         " ORDER BY priority DESC;");
 497                 query.bind(":type").integer(type);
 498                 while (query.nextRow()) {
 499                         bool allow = int(query[0]);
 500                         const char *reqString = query[1];
 501                         SQLite3::int64 id = query[2];
 502                         const char *label = query[3];
 503                         //sqlite_uint64 ruleFlags = query[4];
 504                         SQLite3::int64 disabled = query[5];
 505
 506                         CFRef<SecRequirementRef> requirement;
 507                         MacOSError::check(SecRequirementCreateWithString(CFTempString(reqString), kSecCSDefaultFlags, &requirement.aref()));
 508                         switch (OSStatus rc = SecRequirementEvaluate(requirement, chain, NULL, kSecCSDefaultFlags)) {
 509                         case errSecSuccess: // success
 510                                 break;
 511                         case errSecCSReqFailed: // requirement missed, but otherwise okay
 512                                 continue;
 513                         default: // broken in some way; all tests will fail like this so bail out
 514                                 MacOSError::throwMe(rc);
 515                         }
 516                         if (disabled) {
 517                                 if (latentID == 0) {
 518                                         latentID = id;
 519                                         if (label)
 520                                                 latentLabel = label;
 521                                 }
 522                                 continue;       // the loop
 523                         }
 524
 525                         if (SYSPOLICY_ASSESS_OUTCOME_ACCEPT_ENABLED() || SYSPOLICY_ASSESS_OUTCOME_DENY_ENABLED()) {
 526                                 if (allow)
 527                                         SYSPOLICY_ASSESS_OUTCOME_ACCEPT(cfString(path).c_str(), type, label, NULL);
 528                                 else
 529                                         SYSPOLICY_ASSESS_OUTCOME_DENY(cfString(path).c_str(), type, label, NULL);
 530                         }
 531
 532                         // not adding to the object cache - we could, but it's not likely to be worth it
 533                         cfadd(result, "{%O=%B}", kSecAssessmentAssessmentVerdict, allow);
 534                         addAuthority(flags, result, label, id);
 535                         return;
 536                 }
 537         }
 538         if (SYSPOLICY_ASSESS_OUTCOME_DEFAULT_ENABLED())
 539                 SYSPOLICY_ASSESS_OUTCOME_DEFAULT(cfString(path).c_str(), type, latentLabel.c_str(), NULL);
 540
 541         // no applicable authority. Deny by default
 542         cfadd(result, "{%O=#F}", kSecAssessmentAssessmentVerdict);
 543         addAuthority(flags, result, latentLabel.c_str(), latentID);
 544 }
 545
 546
 547 //
 548 // Create a suitable policy array for verification of installer signatures.
 549 //
 550 static SecPolicyRef makeCRLPolicy()
 551 {
 552         CFRef<SecPolicyRef> policy;
 553         MacOSError::check(SecPolicyCopy(CSSM_CERT_X_509v3, &CSSMOID_APPLE_TP_REVOCATION_CRL, &policy.aref()));
 554         CSSM_APPLE_TP_CRL_OPTIONS options;
 555         memset(&options, 0, sizeof(options));
 556         options.Version = CSSM_APPLE_TP_CRL_OPTS_VERSION;
 557         options.CrlFlags = CSSM_TP_ACTION_FETCH_CRL_FROM_NET | CSSM_TP_ACTION_CRL_SUFFICIENT;
 558         CSSM_DATA optData = { sizeof(options), (uint8 *)&options };
 559         MacOSError::check(SecPolicySetValue(policy, &optData));
 560         return policy.yield();
 561 }
 562
 563 static SecPolicyRef makeOCSPPolicy()
 564 {
 565         CFRef<SecPolicyRef> policy;
 566         MacOSError::check(SecPolicyCopy(CSSM_CERT_X_509v3, &CSSMOID_APPLE_TP_REVOCATION_OCSP, &policy.aref()));
 567         CSSM_APPLE_TP_OCSP_OPTIONS options;
 568         memset(&options, 0, sizeof(options));
 569         options.Version = CSSM_APPLE_TP_OCSP_OPTS_VERSION;
 570         options.Flags = CSSM_TP_ACTION_OCSP_SUFFICIENT;
 571         CSSM_DATA optData = { sizeof(options), (uint8 *)&options };
 572         MacOSError::check(SecPolicySetValue(policy, &optData));
 573         return policy.yield();
 574 }
 575
 576 static CFTypeRef installerPolicy()
 577 {
 578         CFRef<SecPolicyRef> base = SecPolicyCreateBasicX509();
 579         CFRef<SecPolicyRef> crl = makeCRLPolicy();
 580         CFRef<SecPolicyRef> ocsp = makeOCSPPolicy();
 581         return makeCFArray(3, base.get(), crl.get(), ocsp.get());
 582 }
 583
 584
 585 //
 586 // LaunchServices-layer document open.
 587 // We don't cache those at present. If we ever do, we need to authenticate CoreServicesUIAgent as the source of its risk assessment.
 588 //
 589 void PolicyEngine::evaluateDocOpen(CFURLRef path, SecAssessmentFlags flags, CFDictionaryRef context, CFMutableDictionaryRef result)
 590 {
 591         if (context) {
 592                 if (CFStringRef riskCategory = CFStringRef(CFDictionaryGetValue(context, kLSDownloadRiskCategoryKey))) {
 593                         FileQuarantine qtn(cfString(path).c_str());
 594
 595                         if (CFEqual(riskCategory, kLSRiskCategorySafe)
 596                                 || CFEqual(riskCategory, kLSRiskCategoryNeutral)
 597                                 || CFEqual(riskCategory, kLSRiskCategoryUnknown)
 598                                 || CFEqual(riskCategory, kLSRiskCategoryMayContainUnsafeExecutable)) {
 599                                 cfadd(result, "{%O=#T}", kSecAssessmentAssessmentVerdict);
 600                                 addAuthority(flags, result, "_XProtect");
 601                         } else if (qtn.flag(QTN_FLAG_HARD)) {
 602                                 MacOSError::throwMe(errSecCSFileHardQuarantined);
 603                         } else if (qtn.flag(QTN_FLAG_ASSESSMENT_OK)) {
 604                                 cfadd(result, "{%O=#T}", kSecAssessmentAssessmentVerdict);
 605                                 addAuthority(flags, result, "Prior Assessment");
 606                         } else if (!overrideAssessment(flags)) {                // no need to do more work if we're off
 607                                 try {
 608                                         evaluateCode(path, kAuthorityExecute, flags, context, result, false);
 609                                 } catch (...) {
 610                                         // some documents can't be code signed, so this may be quite benign
 611                                 }
 612                         }
 613                         if (CFDictionaryGetValue(result, kSecAssessmentAssessmentVerdict) == NULL) {    // no code signature to help us out
 614                            cfadd(result, "{%O=#F}", kSecAssessmentAssessmentVerdict);
 615                            addAuthority(flags, result, "_XProtect");
 616                         }
 617                         addToAuthority(result, kLSDownloadRiskCategoryKey, riskCategory);
 618                         return;
 619                 }
 620         }
 621         // insufficient information from LS - deny by default
 622         cfadd(result, "{%O=#F}", kSecAssessmentAssessmentVerdict);
 623         addAuthority(flags, result, "Insufficient Context");
 624 }
 625
 626
 627 //
 628 // Result-creation helpers
 629 //
 630 void PolicyEngine::addAuthority(SecAssessmentFlags flags, CFMutableDictionaryRef parent, const char *label, SQLite::int64 row, CFTypeRef cacheInfo, bool weak)
 631 {
 632         CFRef<CFMutableDictionaryRef> auth = makeCFMutableDictionary();
 633         if (label && label[0])
 634                 cfadd(auth, "{%O=%s}", kSecAssessmentAssessmentSource, label);
 635         if (row)
 636                 CFDictionaryAddValue(auth, kSecAssessmentAssessmentAuthorityRow, CFTempNumber(row));
 637         if (overrideAssessment(flags))
 638                 CFDictionaryAddValue(auth, kSecAssessmentAssessmentAuthorityOverride, kDisabledOverride);
 639         if (cacheInfo)
 640                 CFDictionaryAddValue(auth, kSecAssessmentAssessmentFromCache, cacheInfo);
 641         if (weak) {
 642                 CFDictionaryAddValue(auth, kSecAssessmentAssessmentWeakSignature, kCFBooleanTrue);
 643                 CFDictionaryReplaceValue(parent, kSecAssessmentAssessmentAuthority, auth);
 644         } else {
 645                 CFDictionaryAddValue(parent, kSecAssessmentAssessmentAuthority, auth);
 646         }
 647 }
 648
 649 void PolicyEngine::addToAuthority(CFMutableDictionaryRef parent, CFStringRef key, CFTypeRef value)
 650 {
 651         CFMutableDictionaryRef authority = CFMutableDictionaryRef(CFDictionaryGetValue(parent, kSecAssessmentAssessmentAuthority));
 652         assert(authority);
 653         CFDictionaryAddValue(authority, key, value);
 654 }
 655
 656
 657 //
 658 // Add a rule to the policy database
 659 //
 660 CFDictionaryRef PolicyEngine::add(CFTypeRef inTarget, AuthorityType type, SecAssessmentFlags flags, CFDictionaryRef context)
 661 {
 662         // default type to execution
 663         if (type == kAuthorityInvalid)
 664                 type = kAuthorityExecute;
 665
 666         authorizeUpdate(flags, context);
 667         CFDictionary ctx(context, errSecCSInvalidAttributeValues);
 668         CFCopyRef<CFTypeRef> target = inTarget;
 669         CFRef<CFDataRef> bookmark = NULL;
 670         std::string filter_unsigned;
 671
 672         switch (type) {
 673         case kAuthorityExecute:
 674                 normalizeTarget(target, type, ctx, &filter_unsigned);
 675                 // bookmarks are untrusted and just a hint to callers
 676                 bookmark = ctx.get<CFDataRef>(kSecAssessmentRuleKeyBookmark);
 677                 break;
 678         case kAuthorityInstall:
 679                 if (inTarget && CFGetTypeID(inTarget) == CFURLGetTypeID()) {
 680                         // no good way to turn an installer file into a requirement. Pretend to succeeed so caller proceeds
 681                         CFRef<CFArrayRef> properties = makeCFArray(2, kCFURLFileResourceIdentifierKey, kCFURLContentModificationDateKey);
 682                         CFRef<CFErrorRef> error;
 683                         CFURLBookmarkCreationOptions options = kCFURLBookmarkCreationDoNotIncludeSandboxExtensionsMask | kCFURLBookmarkCreationMinimalBookmarkMask;
 684                         if (CFRef<CFDataRef> bookmark = CFURLCreateBookmarkData(NULL, CFURLRef(inTarget), options, properties, NULL, &error.aref())) {
 685                                 UnixPlusPlus::AutoFileDesc fd(lastApprovedFile, O_WRONLY | O_CREAT | O_TRUNC);
 686                                 fd.write(CFDataGetBytePtr(bookmark), CFDataGetLength(bookmark));
 687                                 return NULL;
 688                         }
 689                 }
 690                 break;
 691         case kAuthorityOpenDoc:
 692                 // handle document-open differently: use quarantine flags for whitelisting
 693                 if (!target || CFGetTypeID(target) != CFURLGetTypeID()) // can only "add" file paths
 694                         MacOSError::throwMe(errSecCSInvalidObjectRef);
 695                 try {
 696                         std::string spath = cfString(target.as<CFURLRef>());
 697                         FileQuarantine qtn(spath.c_str());
 698                         qtn.setFlag(QTN_FLAG_ASSESSMENT_OK);
 699                         qtn.applyTo(spath.c_str());
 700                 } catch (const CommonError &error) {
 701                         // could not set quarantine flag - report qualified success
 702                         return cfmake<CFDictionaryRef>("{%O=%O,'assessment:error'=%d}",
 703                                 kSecAssessmentAssessmentAuthorityOverride, CFSTR("error setting quarantine"), error.osStatus());
 704                 } catch (...) {
 705                         return cfmake<CFDictionaryRef>("{%O=%O}", kSecAssessmentAssessmentAuthorityOverride, CFSTR("unable to set quarantine"));
 706                 }
 707                 return NULL;
 708         }
 709
 710         // if we now have anything else, we're busted
 711         if (!target || CFGetTypeID(target) != SecRequirementGetTypeID())
 712                 MacOSError::throwMe(errSecCSInvalidObjectRef);
 713
 714         double priority = 0;
 715         string label;
 716         bool allow = true;
 717         double expires = never;
 718         string remarks;
 719         SQLite::uint64 dbFlags = kAuthorityFlagWhitelistV2;
 720
 721         if (CFNumberRef pri = ctx.get<CFNumberRef>(kSecAssessmentUpdateKeyPriority))
 722                 CFNumberGetValue(pri, kCFNumberDoubleType, &priority);
 723         if (CFStringRef lab = ctx.get<CFStringRef>(kSecAssessmentUpdateKeyLabel))
 724                 label = cfString(lab);
 725         if (CFDateRef time = ctx.get<CFDateRef>(kSecAssessmentUpdateKeyExpires))
 726                 // we're using Julian dates here; convert from CFDate
 727                 expires = dateToJulian(time);
 728         if (CFBooleanRef allowing = ctx.get<CFBooleanRef>(kSecAssessmentUpdateKeyAllow))
 729                 allow = allowing == kCFBooleanTrue;
 730         if (CFStringRef rem = ctx.get<CFStringRef>(kSecAssessmentUpdateKeyRemarks))
 731                 remarks = cfString(rem);
 732
 733         CFRef<CFStringRef> requirementText;
 734         MacOSError::check(SecRequirementCopyString(target.as<SecRequirementRef>(), kSecCSDefaultFlags, &requirementText.aref()));
 735         SQLite::Transaction xact(*this, SQLite3::Transaction::deferred, "add_rule");
 736         SQLite::Statement insert(*this,
 737                 "INSERT INTO authority (type, allow, requirement, priority, label, expires, filter_unsigned, remarks, flags)"
 738                 "       VALUES (:type, :allow, :requirement, :priority, :label, :expires, :filter_unsigned, :remarks, :flags);");
 739         insert.bind(":type").integer(type);
 740         insert.bind(":allow").integer(allow);
 741         insert.bind(":requirement") = requirementText.get();
 742         insert.bind(":priority") = priority;
 743         if (!label.empty())
 744                 insert.bind(":label") = label;
 745         insert.bind(":expires") = expires;
 746         insert.bind(":filter_unsigned") = filter_unsigned.empty() ? NULL : filter_unsigned.c_str();
 747         if (!remarks.empty())
 748                 insert.bind(":remarks") = remarks;
 749         insert.bind(":flags").integer(dbFlags);
 750         insert.execute();
 751         SQLite::int64 newRow = this->lastInsert();
 752         if (bookmark) {
 753                 SQLite::Statement bi(*this, "INSERT INTO bookmarkhints (bookmark, authority) VALUES (:bookmark, :authority)");
 754                 bi.bind(":bookmark") = CFDataRef(bookmark);
 755                 bi.bind(":authority").integer(newRow);
 756                 bi.execute();
 757         }
 758         this->purgeObjects(priority);
 759         xact.commit();
 760         notify_post(kNotifySecAssessmentUpdate);
 761         return cfmake<CFDictionaryRef>("{%O=%d}", kSecAssessmentUpdateKeyRow, newRow);
 762 }
 763
 764
 765 CFDictionaryRef PolicyEngine::remove(CFTypeRef target, AuthorityType type, SecAssessmentFlags flags, CFDictionaryRef context)
 766 {
 767         if (type == kAuthorityOpenDoc) {
 768                 // handle document-open differently: use quarantine flags for whitelisting
 769                 authorizeUpdate(flags, context);
 770                 if (!target || CFGetTypeID(target) != CFURLGetTypeID())
 771                         MacOSError::throwMe(errSecCSInvalidObjectRef);
 772                 std::string spath = cfString(CFURLRef(target)).c_str();
 773                 FileQuarantine qtn(spath.c_str());
 774                 qtn.clearFlag(QTN_FLAG_ASSESSMENT_OK);
 775                 qtn.applyTo(spath.c_str());
 776                 return NULL;
 777         }
 778         return manipulateRules("DELETE FROM authority", target, type, flags, context, true);
 779 }
 780
 781 CFDictionaryRef PolicyEngine::enable(CFTypeRef target, AuthorityType type, SecAssessmentFlags flags, CFDictionaryRef context, bool authorize)
 782 {
 783         return manipulateRules("UPDATE authority SET disabled = 0", target, type, flags, context, authorize);
 784 }
 785
 786 CFDictionaryRef PolicyEngine::disable(CFTypeRef target, AuthorityType type, SecAssessmentFlags flags, CFDictionaryRef context, bool authorize)
 787 {
 788         return manipulateRules("UPDATE authority SET disabled = 1", target, type, flags, context, authorize);
 789 }
 790
 791 CFDictionaryRef PolicyEngine::find(CFTypeRef target, AuthorityType type, SecAssessmentFlags flags, CFDictionaryRef context)
 792 {
 793         SQLite::Statement query(*this);
 794         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",
 795                 "scan_authority", target, type, flags, context,
 796                 " ORDER BY priority DESC");
 797         CFRef<CFMutableArrayRef> found = makeCFMutableArray(0);
 798         while (query.nextRow()) {
 799                 SQLite::int64 id = query[0];
 800                 int type = int(query[1]);
 801                 const char *requirement = query[2];
 802                 int allow = int(query[3]);
 803                 const char *label = query[4];
 804                 double priority = query[5];
 805                 const char *remarks = query[6];
 806                 double expires = query[7];
 807                 int disabled = int(query[8]);
 808                 CFRef<CFDataRef> bookmark = query[9].data();
 809                 CFRef<CFMutableDictionaryRef> rule = makeCFMutableDictionary(5,
 810                         kSecAssessmentRuleKeyID, CFTempNumber(id).get(),
 811                         kSecAssessmentRuleKeyType, CFRef<CFStringRef>(typeNameFor(type)).get(),
 812                         kSecAssessmentRuleKeyRequirement, CFTempString(requirement).get(),
 813                         kSecAssessmentRuleKeyAllow, allow ? kCFBooleanTrue : kCFBooleanFalse,
 814                         kSecAssessmentRuleKeyPriority, CFTempNumber(priority).get()
 815                         );
 816                 if (label)
 817                         CFDictionaryAddValue(rule, kSecAssessmentRuleKeyLabel, CFTempString(label));
 818                 if (remarks)
 819                         CFDictionaryAddValue(rule, kSecAssessmentRuleKeyRemarks, CFTempString(remarks));
 820                 if (expires != never)
 821                         CFDictionaryAddValue(rule, kSecAssessmentRuleKeyExpires, CFRef<CFDateRef>(julianToDate(expires)));
 822                 if (disabled)
 823                         CFDictionaryAddValue(rule, kSecAssessmentRuleKeyDisabled, CFTempNumber(disabled));
 824                 if (bookmark)
 825                         CFDictionaryAddValue(rule, kSecAssessmentRuleKeyBookmark, bookmark);
 826                 CFArrayAppendValue(found, rule);
 827         }
 828         if (CFArrayGetCount(found) == 0)
 829                 MacOSError::throwMe(errSecCSNoMatches);
 830         return cfmake<CFDictionaryRef>("{%O=%O}", kSecAssessmentUpdateKeyFound, found.get());
 831 }
 832
 833
 834 CFDictionaryRef PolicyEngine::update(CFTypeRef target, SecAssessmentFlags flags, CFDictionaryRef context)
 835 {
 836         // update GKE
 837         installExplicitSet(gkeAuthFile, gkeSigsFile);
 838
 839         AuthorityType type = typeFor(context, kAuthorityInvalid);
 840         CFStringRef edit = CFStringRef(CFDictionaryGetValue(context, kSecAssessmentContextKeyUpdate));
 841         CFDictionaryRef result;
 842         if (CFEqual(edit, kSecAssessmentUpdateOperationAdd))
 843                 result = this->add(target, type, flags, context);
 844         else if (CFEqual(edit, kSecAssessmentUpdateOperationRemove))
 845                 result = this->remove(target, type, flags, context);
 846         else if (CFEqual(edit, kSecAssessmentUpdateOperationEnable))
 847                 result = this->enable(target, type, flags, context, true);
 848         else if (CFEqual(edit, kSecAssessmentUpdateOperationDisable))
 849                 result = this->disable(target, type, flags, context, true);
 850         else if (CFEqual(edit, kSecAssessmentUpdateOperationFind))
 851                 result = this->find(target, type, flags, context);
 852         else
 853                 MacOSError::throwMe(errSecCSInvalidAttributeValues);
 854         if (result == NULL)
 855                 result = makeCFDictionary(0);           // success, no details
 856         return result;
 857 }
 858
 859
 860 //
 861 // Construct and prepare an SQL query on the authority table, operating on some set of existing authority records.
 862 // In essence, this appends a suitable WHERE clause to the stanza passed and prepares it on the statement given.
 863 //
 864 void PolicyEngine::selectRules(SQLite::Statement &action, std::string phrase, std::string table,
 865         CFTypeRef inTarget, AuthorityType type, SecAssessmentFlags flags, CFDictionaryRef context, std::string suffix /* = "" */)
 866 {
 867         CFDictionary ctx(context, errSecCSInvalidAttributeValues);
 868         CFCopyRef<CFTypeRef> target = inTarget;
 869         std::string filter_unsigned;    // ignored; used just to trigger ad-hoc signing
 870         normalizeTarget(target, type, ctx, &filter_unsigned);
 871
 872         string label;
 873         if (CFStringRef lab = ctx.get<CFStringRef>(kSecAssessmentUpdateKeyLabel))
 874                 label = cfString(CFStringRef(lab));
 875
 876         if (!target) {
 877                 if (label.empty()) {
 878                         if (type == kAuthorityInvalid) {
 879                                 action.query(phrase + suffix);
 880                         } else {
 881                                 action.query(phrase + " WHERE " + table + ".type = :type" + suffix);
 882                                 action.bind(":type").integer(type);
 883                         }
 884                 } else {        // have label
 885                         if (type == kAuthorityInvalid) {
 886                                 action.query(phrase + " WHERE " + table + ".label = :label" + suffix);
 887                         } else {
 888                                 action.query(phrase + " WHERE " + table + ".type = :type AND " + table + ".label = :label" + suffix);
 889                                 action.bind(":type").integer(type);
 890                         }
 891                         action.bind(":label") = label;
 892                 }
 893         } else if (CFGetTypeID(target) == CFNumberGetTypeID()) {
 894                 action.query(phrase + " WHERE " + table + ".id = :id" + suffix);
 895                 action.bind(":id").integer(cfNumber<uint64_t>(target.as<CFNumberRef>()));
 896         } else if (CFGetTypeID(target) == SecRequirementGetTypeID()) {
 897                 if (type == kAuthorityInvalid)
 898                         type = kAuthorityExecute;
 899                 CFRef<CFStringRef> requirementText;
 900                 MacOSError::check(SecRequirementCopyString(target.as<SecRequirementRef>(), kSecCSDefaultFlags, &requirementText.aref()));
 901                 action.query(phrase + " WHERE " + table + ".type = :type AND " + table + ".requirement = :requirement" + suffix);
 902                 action.bind(":type").integer(type);
 903                 action.bind(":requirement") = requirementText.get();
 904         } else
 905                 MacOSError::throwMe(errSecCSInvalidObjectRef);
 906 }
 907
 908
 909 //
 910 // Execute an atomic change to existing records in the authority table.
 911 //
 912 CFDictionaryRef PolicyEngine::manipulateRules(const std::string &stanza,
 913         CFTypeRef inTarget, AuthorityType type, SecAssessmentFlags flags, CFDictionaryRef context, bool authorize)
 914 {
 915         SQLite::Transaction xact(*this, SQLite3::Transaction::deferred, "rule_change");
 916         SQLite::Statement action(*this);
 917         if (authorize)
 918                 authorizeUpdate(flags, context);
 919         selectRules(action, stanza, "authority", inTarget, type, flags, context);
 920         action.execute();
 921         unsigned int changes = this->changes(); // latch change count
 922         // We MUST purge objects with priority <= MAX(priority of any changed rules);
 923         // but for now we just get lazy and purge them ALL.
 924         if (changes) {
 925                 this->purgeObjects(1.0E100);
 926                 xact.commit();
 927                 notify_post(kNotifySecAssessmentUpdate);
 928                 return cfmake<CFDictionaryRef>("{%O=%d}", kSecAssessmentUpdateKeyCount, changes);
 929         }
 930         // no change; return an error
 931         MacOSError::throwMe(errSecCSNoMatches);
 932 }
 933
 934
 935 //
 936 // Fill in extra information about the originator of cryptographic credentials found - if any
 937 //
 938 void PolicyEngine::setOrigin(CFArrayRef chain, CFMutableDictionaryRef result)
 939 {
 940         if (chain)
 941                 if (CFArrayGetCount(chain) > 0)
 942                         if (SecCertificateRef leaf = SecCertificateRef(CFArrayGetValueAtIndex(chain, 0)))
 943                                 if (CFStringRef summary = SecCertificateCopyLongDescription(NULL, leaf, NULL)) {
 944                                         CFDictionarySetValue(result, kSecAssessmentAssessmentOriginator, summary);
 945                                         CFRelease(summary);
 946                                 }
 947 }
 948
 949
 950 //
 951 // Take an assessment outcome and record it in the object cache
 952 //
 953 void PolicyEngine::recordOutcome(SecStaticCodeRef code, bool allow, AuthorityType type, double expires, SQLite::int64 authority)
 954 {
 955         CFRef<CFDictionaryRef> info;
 956         MacOSError::check(SecCodeCopySigningInformation(code, kSecCSDefaultFlags, &info.aref()));
 957         CFDataRef cdHash = CFDataRef(CFDictionaryGetValue(info, kSecCodeInfoUnique));
 958         assert(cdHash);         // was signed
 959         CFRef<CFURLRef> path;
 960         MacOSError::check(SecCodeCopyPath(code, kSecCSDefaultFlags, &path.aref()));
 961         assert(expires);
 962         SQLite::Transaction xact(*this, SQLite3::Transaction::deferred, "caching");
 963         SQLite::Statement insert(*this,
 964                 "INSERT OR REPLACE INTO object (type, allow, hash, expires, path, authority)"
 965                 "       VALUES (:type, :allow, :hash, :expires, :path,"
 966                 "       CASE :authority WHEN 0 THEN (SELECT id FROM authority WHERE label = 'No Matching Rule') ELSE :authority END"
 967                 "       );");
 968         insert.bind(":type").integer(type);
 969         insert.bind(":allow").integer(allow);
 970         insert.bind(":hash") = cdHash;
 971         insert.bind(":expires") = expires;
 972         insert.bind(":path") = cfString(path);
 973         insert.bind(":authority").integer(authority);
 974         insert.execute();
 975         xact.commit();
 976 }
 977
 978
 979 //
 980 // Record a UI failure record after proper validation of the caller
 981 //
 982 void PolicyEngine::recordFailure(CFDictionaryRef info)
 983 {
 984         CFRef<CFDataRef> infoData = makeCFData(info);
 985         UnixPlusPlus::AutoFileDesc fd(lastRejectFile, O_WRONLY | O_CREAT | O_TRUNC);
 986         fd.write(CFDataGetBytePtr(infoData), CFDataGetLength(infoData));
 987         notify_post(kNotifySecAssessmentRecordingChange);
 988 }
 989
 990
 991 //
 992 // Perform update authorization processing.
 993 // Throws an exception if authorization is denied.
 994 //
 995 static void authorizeUpdate(SecAssessmentFlags flags, CFDictionaryRef context)
 996 {
 997         AuthorizationRef authorization = NULL;
 998
 999         if (context)
1000                 if (CFTypeRef authkey = CFDictionaryGetValue(context, kSecAssessmentUpdateKeyAuthorization))
1001                         if (CFGetTypeID(authkey) == CFDataGetTypeID()) {
1002                                 CFDataRef authdata = CFDataRef(authkey);
1003                                 if (CFDataGetLength(authdata) != sizeof(AuthorizationExternalForm))
1004                                         MacOSError::throwMe(errSecCSInvalidObjectRef);
1005                                 MacOSError::check(AuthorizationCreateFromExternalForm((AuthorizationExternalForm *)CFDataGetBytePtr(authdata), &authorization));
1006                         }
1007         if (authorization == NULL)
1008                 MacOSError::throwMe(errSecCSDBDenied);
1009
1010         AuthorizationItem right[] = {
1011                 { "com.apple.security.assessment.update", 0, NULL, 0 }
1012         };
1013         AuthorizationRights rights = { sizeof(right) / sizeof(right[0]), right };
1014         MacOSError::check(AuthorizationCopyRights(authorization, &rights, NULL,
1015                 kAuthorizationFlagExtendRights | kAuthorizationFlagInteractionAllowed, NULL));
1016
1017         MacOSError::check(AuthorizationFree(authorization, kAuthorizationFlagDefaults));
1018 }
1019
1020
1021 //
1022 // Perform common argument normalizations for update operations
1023 //
1024 void PolicyEngine::normalizeTarget(CFRef<CFTypeRef> &target, AuthorityType type, CFDictionary &context, std::string *signUnsigned)
1025 {
1026         // turn CFURLs into (designated) SecRequirements
1027         if (target && CFGetTypeID(target) == CFURLGetTypeID()) {
1028                 CFRef<SecStaticCodeRef> code;
1029                 CFURLRef path = target.as<CFURLRef>();
1030                 MacOSError::check(SecStaticCodeCreateWithPath(path, kSecCSDefaultFlags, &code.aref()));
1031                 switch (OSStatus rc = SecCodeCopyDesignatedRequirement(code, kSecCSDefaultFlags, (SecRequirementRef *)&target.aref())) {
1032                 case errSecSuccess: {
1033                         // use the *default* DR to avoid unreasonably wide DRs opening up Gatekeeper to attack
1034                         CFRef<CFDictionaryRef> info;
1035                         MacOSError::check(SecCodeCopySigningInformation(code, kSecCSRequirementInformation, &info.aref()));
1036                         target = CFDictionaryGetValue(info, kSecCodeInfoImplicitDesignatedRequirement);
1037                         }
1038                         break;
1039                 case errSecCSUnsigned:
1040                         if (signUnsigned && temporarySigning(code, type, path, kAuthorityFlagWhitelistV2)) {    // ad-hoc signed the code temporarily
1041                                 MacOSError::check(SecCodeCopyDesignatedRequirement(code, kSecCSDefaultFlags, (SecRequirementRef *)&target.aref()));
1042                                 CFRef<CFDictionaryRef> info;
1043                                 MacOSError::check(SecCodeCopySigningInformation(code, kSecCSInternalInformation, &info.aref()));
1044                                 if (CFDataRef cdData = CFDataRef(CFDictionaryGetValue(info, kSecCodeInfoCodeDirectory)))
1045                                         *signUnsigned = ((const CodeDirectory *)CFDataGetBytePtr(cdData))->screeningCode();
1046                                 break;
1047                         }
1048                         MacOSError::check(rc);
1049                 case errSecCSSignatureFailed:
1050                         // recover certain cases of broken signatures (well, try)
1051                         if (codeInvalidityExceptions(code, NULL)) {
1052                                 // Ad-hoc sign the code in place (requiring a writable subject). This requires root privileges.
1053                                 CFRef<SecCodeSignerRef> signer;
1054                                 CFTemp<CFDictionaryRef> arguments("{%O=#N}", kSecCodeSignerIdentity);
1055                                 MacOSError::check(SecCodeSignerCreate(arguments, kSecCSSignOpaque, &signer.aref()));
1056                                 MacOSError::check(SecCodeSignerAddSignature(signer, code, kSecCSDefaultFlags));
1057                                 MacOSError::check(SecCodeCopyDesignatedRequirement(code, kSecCSDefaultFlags, (SecRequirementRef *)&target.aref()));
1058                                 break;
1059                         }
1060                         MacOSError::check(rc);
1061                 default:
1062                         MacOSError::check(rc);
1063                 }
1064                 if (context.get(kSecAssessmentUpdateKeyRemarks) == NULL)        {
1065                         // no explicit remarks; add one with the path
1066                         CFRef<CFURLRef> path;
1067                         MacOSError::check(SecCodeCopyPath(code, kSecCSDefaultFlags, &path.aref()));
1068                         CFMutableDictionaryRef dict = makeCFMutableDictionary(context.get());
1069                         CFDictionaryAddValue(dict, kSecAssessmentUpdateKeyRemarks, CFTempString(cfString(path)));
1070                         context.take(dict);
1071                 }
1072                 CFStringRef edit = CFStringRef(context.get(kSecAssessmentContextKeyUpdate));
1073                 if (type == kAuthorityExecute && CFEqual(edit, kSecAssessmentUpdateOperationAdd)) {
1074                         // implicitly whitelist the code
1075                         mOpaqueWhitelist.add(code);
1076                 }
1077         }
1078 }
1079
1080
1081 //
1082 // Process special overrides for invalidly signed code.
1083 // This is the (hopefully minimal) concessions we make to keep hurting our customers
1084 // for our own prior mistakes...
1085 //
1086 static bool codeInvalidityExceptions(SecStaticCodeRef code, CFMutableDictionaryRef result)
1087 {
1088         if (OSAIsRecognizedExecutableURL) {
1089                 CFRef<CFDictionaryRef> info;
1090                 MacOSError::check(SecCodeCopySigningInformation(code, kSecCSDefaultFlags, &info.aref()));
1091                 if (CFURLRef executable = CFURLRef(CFDictionaryGetValue(info, kSecCodeInfoMainExecutable))) {
1092                         SInt32 error;
1093                         if (OSAIsRecognizedExecutableURL(executable, &error)) {
1094                                 if (result)
1095                                         CFDictionaryAddValue(result,
1096                                                 kSecAssessmentAssessmentAuthorityOverride, CFSTR("ignoring known invalid applet signature"));
1097                                 return true;
1098                         }
1099                 }
1100         }
1101         return false;
1102 }
1103
1104
1105 } // end namespace CodeSigning
1106 } // end namespace Security