OSX/libsecurity_codesigning/lib/signer.cpp

   1 /*
   2  * Copyright (c) 2006-2014 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
  24 //
  25 // signer - Signing operation supervisor and controller
  26 //
  27 #include "signer.h"
  28 #include "resources.h"
  29 #include "signerutils.h"
  30 #include "SecCodeSigner.h"
  31 #include <Security/SecIdentity.h>
  32 #include <Security/CMSEncoder.h>
  33 #include <Security/CMSPrivate.h>
  34 #include <Security/CSCommonPriv.h>
  35 #include <CoreFoundation/CFBundlePriv.h>
  36 #include "resources.h"
  37 #include "machorep.h"
  38 #include "reqparser.h"
  39 #include "reqdumper.h"
  40 #include "csutilities.h"
  41 #include <security_utilities/unix++.h>
  42 #include <security_utilities/unixchild.h>
  43 #include <security_utilities/cfmunge.h>
  44 #include <security_utilities/dispatch.h>
  45 #include <IOKit/storage/IOStorageDeviceCharacteristics.h>
  46
  47 namespace Security {
  48 namespace CodeSigning {
  49
  50
  51 //
  52 // Sign some code.
  53 //
  54 void SecCodeSigner::Signer::sign(SecCSFlags flags)
  55 {
  56         rep = code->diskRep()->base();
  57         this->prepare(flags);
  58
  59         PreSigningContext context(*this);
  60
  61         considerTeamID(context);
  62
  63         if (Universal *fat = state.mNoMachO ? NULL : rep->mainExecutableImage()) {
  64                 signMachO(fat, context);
  65         } else {
  66                 signArchitectureAgnostic(context);
  67         }
  68 }
  69
  70
  71 void SecCodeSigner::Signer::considerTeamID(const PreSigningContext& context)
  72 {
  73         /* If an explicit teamID was passed in it must be
  74          the same as what came from the cert */
  75         std::string teamIDFromCert = state.getTeamIDFromSigner(context.certs);
  76
  77         if (state.mPreserveMetadata & kSecCodeSignerPreserveTeamIdentifier) {
  78                 /* If preserving the team identifier, teamID is set previously when the
  79                  code object is still available */
  80                 if (!teamIDFromCert.empty() && teamID != teamIDFromCert)
  81                         MacOSError::throwMe(errSecCSInvalidFlags);
  82         } else {
  83                 if (teamIDFromCert.empty()) {
  84                         /* state.mTeamID is an explicitly passed teamID */
  85                         teamID = state.mTeamID;
  86                 } else if (state.mTeamID.empty() || (state.mTeamID == teamIDFromCert)) {
  87                         /* If there was no explicit team ID set, or the explicit team ID matches
  88                          what is in the cert, use the team ID from the certificate */
  89                         teamID = teamIDFromCert;
  90                 } else {
  91                         /* The caller passed in an explicit team ID that does not match what is
  92                          in the signing cert, which is an invalid usage */
  93                         MacOSError::throwMe(errSecCSInvalidFlags);
  94                 }
  95         }
  96 }
  97
  98
  99 //
 100 // Remove any existing code signature from code
 101 //
 102 void SecCodeSigner::Signer::remove(SecCSFlags flags)
 103 {
 104         // can't remove a detached signature
 105         if (state.mDetached)
 106                 MacOSError::throwMe(errSecCSNotSupported);
 107
 108         rep = code->diskRep();
 109         if (Universal *fat = state.mNoMachO ? NULL : rep->mainExecutableImage()) {
 110                 // architecture-sensitive removal
 111                 MachOEditor editor(rep->writer(), *fat, digestAlgorithms(), rep->mainExecutablePath());
 112                 editor.allocate();              // create copy
 113                 editor.commit();                // commit change
 114         } else {
 115                 // architecture-agnostic removal
 116                 RefPointer<DiskRep::Writer> writer = rep->writer();
 117                 writer->remove();
 118                 writer->flush();
 119         }
 120 }
 121
 122
 123 //
 124 // Contemplate the object-to-be-signed and set up the Signer state accordingly.
 125 //
 126 void SecCodeSigner::Signer::prepare(SecCSFlags flags)
 127 {
 128         // make sure the rep passes strict validation
 129         if (strict)
 130                 rep->strictValidate(NULL, MacOSErrorSet(), flags);
 131
 132         // initialize progress/cancellation state
 133         code->prepareProgress(0);                       // totally fake workload - we don't know how many files we'll encounter
 134
 135         // get the Info.plist out of the rep for some creative defaulting
 136         CFRef<CFDictionaryRef> infoDict;
 137         if (CFRef<CFDataRef> infoData = rep->component(cdInfoSlot))
 138                 infoDict.take(makeCFDictionaryFrom(infoData));
 139
 140         uint32_t inherit = code->isSigned() ? state.mPreserveMetadata : 0;
 141
 142         // work out the canonical identifier
 143         identifier = state.mIdentifier;
 144         if (identifier.empty() && (inherit & kSecCodeSignerPreserveIdentifier))
 145                 identifier = code->identifier();
 146         if (identifier.empty()) {
 147                 identifier = rep->recommendedIdentifier(*this);
 148                 if (identifier.find('.') == string::npos)
 149                         identifier = state.mIdentifierPrefix + identifier;
 150                 if (identifier.find('.') == string::npos && isAdhoc())
 151                         identifier = identifier + "-" + uniqueName();
 152                 secdebug("signer", "using default identifier=%s", identifier.c_str());
 153         } else
 154                 secdebug("signer", "using explicit identifier=%s", identifier.c_str());
 155
 156         teamID = state.mTeamID;
 157         if (teamID.empty() && (inherit & kSecCodeSignerPreserveTeamIdentifier)) {
 158                 const char *c_id = code->teamID();
 159                 if (c_id)
 160                         teamID = c_id;
 161         }
 162
 163         // Digest algorithms: explicit or preserved. Subject to diskRep defaults or final default later.
 164         hashAlgorithms = state.mDigestAlgorithms;
 165         if (hashAlgorithms.empty() && (inherit & kSecCodeSignerPreserveDigestAlgorithm))
 166                 hashAlgorithms = code->hashAlgorithms();
 167
 168         entitlements = state.mEntitlementData;
 169         if (!entitlements && (inherit & kSecCodeSignerPreserveEntitlements))
 170                 entitlements = code->component(cdEntitlementSlot);
 171
 172         // work out the CodeDirectory flags word
 173         bool haveCdFlags = false;
 174         if (!haveCdFlags && state.mCdFlagsGiven) {
 175                 cdFlags = state.mCdFlags;
 176                 secdebug("signer", "using explicit cdFlags=0x%x", cdFlags);
 177                 haveCdFlags = true;
 178         }
 179         if (!haveCdFlags) {
 180                 cdFlags = 0;
 181                 if (infoDict)
 182                         if (CFTypeRef csflags = CFDictionaryGetValue(infoDict, CFSTR("CSFlags"))) {
 183                                 if (CFGetTypeID(csflags) == CFNumberGetTypeID()) {
 184                                         cdFlags = cfNumber<uint32_t>(CFNumberRef(csflags));
 185                                         secdebug("signer", "using numeric cdFlags=0x%x from Info.plist", cdFlags);
 186                                 } else if (CFGetTypeID(csflags) == CFStringGetTypeID()) {
 187                                         cdFlags = cdTextFlags(cfString(CFStringRef(csflags)));
 188                                         secdebug("signer", "using text cdFlags=0x%x from Info.plist", cdFlags);
 189                                 } else
 190                                         MacOSError::throwMe(errSecCSBadDictionaryFormat);
 191                                 haveCdFlags = true;
 192                         }
 193         }
 194         if (!haveCdFlags && (inherit & kSecCodeSignerPreserveFlags)) {
 195                 cdFlags = code->codeDirectory(false)->flags & ~kSecCodeSignatureAdhoc;
 196                 secdebug("signer", "using inherited cdFlags=0x%x", cdFlags);
 197                 haveCdFlags = true;
 198         }
 199         if (!haveCdFlags)
 200                 cdFlags = 0;
 201         if (state.mSigner == SecIdentityRef(kCFNull))   // ad-hoc signing requested...
 202                 cdFlags |= kSecCodeSignatureAdhoc;      // ... so note that
 203
 204         // prepare the internal requirements input
 205         if (state.mRequirements) {
 206                 if (CFGetTypeID(state.mRequirements) == CFDataGetTypeID()) {            // binary form
 207                         const Requirements *rp = (const Requirements *)CFDataGetBytePtr(state.mRequirements.as<CFDataRef>());
 208                         if (!rp->validateBlob())
 209                                 MacOSError::throwMe(errSecCSReqInvalid);
 210                         requirements = rp->clone();
 211                 } else if (CFGetTypeID(state.mRequirements) == CFStringGetTypeID()) { // text form
 212                         CFRef<CFMutableStringRef> reqText = CFStringCreateMutableCopy(NULL, 0, state.mRequirements.as<CFStringRef>());
 213                         // substitute $ variable tokens
 214                         CFRange range = { 0, CFStringGetLength(reqText) };
 215                         CFStringFindAndReplace(reqText, CFSTR("$self.identifier"), CFTempString(identifier), range, 0);
 216                         requirements = parseRequirements(cfString(reqText));
 217                 } else
 218                         MacOSError::throwMe(errSecCSInvalidObjectRef);
 219         } else if (inherit & kSecCodeSignerPreserveRequirements)
 220                 if (const Requirements *rp = code->internalRequirements())
 221                         requirements = rp->clone();
 222
 223         // prepare the resource directory, if any
 224         string rpath = rep->resourcesRootPath();
 225         string rrpath;
 226         CFCopyRef<CFDictionaryRef> resourceRules;
 227         if (!rpath.empty()) {
 228                 // explicitly given resource rules always win
 229                 resourceRules = state.mResourceRules;
 230
 231                 // inherited rules come next (overriding embedded ones!)
 232                 if (!resourceRules && (inherit & kSecCodeSignerPreserveResourceRules))
 233                         if (CFDictionaryRef oldRules = code->resourceDictionary(false))
 234                                 resourceRules = oldRules;
 235
 236                 // embedded resource rules come next
 237                 if (!resourceRules && infoDict)
 238                         if (CFTypeRef spec = CFDictionaryGetValue(infoDict, _kCFBundleResourceSpecificationKey)) {
 239                                 if (CFGetTypeID(spec) == CFStringGetTypeID())
 240                                         if (CFRef<CFDataRef> data = cfLoadFile(rpath + "/" + cfString(CFStringRef(spec))))
 241                                                 if (CFDictionaryRef dict = makeCFDictionaryFrom(data))
 242                                                         resourceRules.take(dict);
 243                                 if (!resourceRules)     // embedded rules present but unacceptable
 244                                         MacOSError::throwMe(errSecCSResourceRulesInvalid);
 245                         }
 246
 247                 // if we got one from anywhere (but the defaults), sanity-check it
 248                 if (resourceRules) {
 249                         CFTypeRef rules = CFDictionaryGetValue(resourceRules, CFSTR("rules"));
 250                         if (!rules || CFGetTypeID(rules) != CFDictionaryGetTypeID())
 251                                 MacOSError::throwMe(errSecCSResourceRulesInvalid);
 252                 }
 253
 254                 // finally, ask the DiskRep for its default
 255                 if (!resourceRules)
 256                         resourceRules.take(rep->defaultResourceRules(*this));
 257
 258                 // resource root can optionally be the canonical bundle path,
 259                 // but sealed resource paths are always relative to rpath
 260                 rrpath = rpath;
 261                 if (signingFlags() & kSecCSSignBundleRoot)
 262                         rrpath = cfStringRelease(rep->copyCanonicalPath());
 263         }
 264
 265         // screen and set the signing time
 266         CFAbsoluteTime now = CFAbsoluteTimeGetCurrent();
 267         if (state.mSigningTime == CFDateRef(kCFNull)) {
 268                 signingTime = 0;                // no time at all
 269         } else if (!state.mSigningTime) {
 270                 signingTime = now;              // default
 271         } else {
 272                 CFAbsoluteTime time = CFDateGetAbsoluteTime(state.mSigningTime);
 273                 if (time > now) // not allowed to post-date a signature
 274                         MacOSError::throwMe(errSecCSBadDictionaryFormat);
 275                 signingTime = time;
 276         }
 277
 278         pagesize = state.mPageSize ? cfNumber<size_t>(state.mPageSize) : rep->pageSize(*this);
 279
 280         // Allow the DiskRep to modify the signing parameters. This sees explicit and inherited values but not defaults.
 281         rep->prepareForSigning(*this);
 282
 283         // apply some defaults after diskRep intervention
 284         if (hashAlgorithms.empty()) {   // default to SHA256 + SHA-1
 285                 hashAlgorithms.insert(kSecCodeSignatureHashSHA1);
 286                 hashAlgorithms.insert(kSecCodeSignatureHashSHA256);
 287         }
 288
 289         // build the resource directory (once and for all, using the digests determined above)
 290         if (!rpath.empty()) {
 291                 buildResources(rrpath, rpath, resourceRules);
 292         }
 293 }
 294
 295
 296 //
 297 // Collect the resource seal for a program.
 298 // This includes both sealed resources and information about nested code.
 299 //
 300 void SecCodeSigner::Signer::buildResources(std::string root, std::string relBase, CFDictionaryRef rulesDict)
 301 {
 302         typedef ResourceBuilder::Rule Rule;
 303
 304         secdebug("codesign", "start building resource directory");
 305         __block CFRef<CFMutableDictionaryRef> result = makeCFMutableDictionary();
 306
 307         CFDictionaryRef rules = cfget<CFDictionaryRef>(rulesDict, "rules");
 308         assert(rules);
 309
 310         if (this->state.mLimitedAsync == NULL) {
 311                 this->state.mLimitedAsync =
 312                         /* rdar://problem/20299541: Async workers (i.e. parallelization) are currently
 313                          * turned off, because the paths for signing code are not ready for it yet. */
 314                         // new LimitedAsync(rep->fd().mediumType() == kIOPropertyMediumTypeSolidStateKey);
 315                         new LimitedAsync(false);
 316         }
 317
 318         CFDictionaryRef files2 = NULL;
 319         if (!(signingFlags() & kSecCSSignV1)) {
 320                 CFCopyRef<CFDictionaryRef> rules2 = cfget<CFDictionaryRef>(rulesDict, "rules2");
 321                 if (!rules2) {
 322                         // Clone V1 rules and add default nesting rules at weight 0 (overridden by anything in rules).
 323                         // V1 rules typically do not cover these places so we'll prevail, but if they do, we defer to them.
 324                         rules2 = cfmake<CFDictionaryRef>("{+%O"
 325                                 "'^(Frameworks|SharedFrameworks|PlugIns|Plug-ins|XPCServices|Helpers|MacOS|Library/(Automator|Spotlight|LoginItems))/' = {nested=#T, weight=0}" // exclude dynamic repositories
 326                         "}", rules);
 327                 }
 328
 329                 Dispatch::Group group;
 330                 Dispatch::Group &groupRef = group;  // (into block)
 331
 332                 // build the modern (V2) resource seal
 333                 __block CFRef<CFMutableDictionaryRef> files = makeCFMutableDictionary();
 334                 CFMutableDictionaryRef filesRef = files.get();  // (into block)
 335                 ResourceBuilder resourceBuilder(root, relBase, rules2, strict, MacOSErrorSet());
 336                 ResourceBuilder &resources = resourceBuilder;   // (into block)
 337                 rep->adjustResources(resources);
 338
 339                 resources.scan(^(FTSENT *ent, uint32_t ruleFlags, const std::string relpath, Rule *rule) {
 340                         bool isSymlink = (ent->fts_info == FTS_SL);
 341                         const std::string path(ent->fts_path);
 342                         const std::string accpath(ent->fts_accpath);
 343                         this->state.mLimitedAsync->perform(groupRef, ^{
 344                                 CFRef<CFMutableDictionaryRef> seal;
 345                                 if (ruleFlags & ResourceBuilder::nested) {
 346                                         seal.take(signNested(path, relpath));
 347                                 } else if (isSymlink) {
 348                                         char target[PATH_MAX];
 349                                         ssize_t len = ::readlink(accpath.c_str(), target, sizeof(target)-1);
 350                                         if (len < 0)
 351                                                 UnixError::check(-1);
 352                                         target[len] = '\0';
 353                                         seal.take(cfmake<CFMutableDictionaryRef>("{symlink=%s}", target));
 354                                 } else {
 355                                         seal.take(resources.hashFile(accpath.c_str(), digestAlgorithms()));
 356                                 }
 357                                 if (ruleFlags & ResourceBuilder::optional)
 358                                         CFDictionaryAddValue(seal, CFSTR("optional"), kCFBooleanTrue);
 359                                 CFTypeRef hash;
 360                                 StLock<Mutex> _(resourceLock);
 361                                 if ((hash = CFDictionaryGetValue(seal, CFSTR("hash"))) && CFDictionaryGetCount(seal) == 1) // simple form
 362                                         CFDictionaryAddValue(filesRef, CFTempString(relpath).get(), hash);
 363                                 else
 364                                         CFDictionaryAddValue(filesRef, CFTempString(relpath).get(), seal.get());
 365                                 code->reportProgress();
 366                         });
 367                 });
 368                 group.wait();
 369                 CFDictionaryAddValue(result, CFSTR("rules2"), resourceBuilder.rules());
 370                 files2 = files;
 371                 CFDictionaryAddValue(result, CFSTR("files2"), files2);
 372         }
 373
 374         CFDictionaryAddValue(result, CFSTR("rules"), rules);    // preserve V1 rules in any case
 375         if (!(signingFlags() & kSecCSSignNoV1)) {
 376                 // build the legacy (V1) resource seal
 377                 __block CFRef<CFMutableDictionaryRef> files = makeCFMutableDictionary();
 378                 ResourceBuilder resourceBuilder(root, relBase, rules, strict, MacOSErrorSet());
 379                 ResourceBuilder &resources = resourceBuilder;
 380                 rep->adjustResources(resources);        // DiskRep-specific adjustments
 381                 resources.scan(^(FTSENT *ent, uint32_t ruleFlags, std::string relpath, Rule *rule) {
 382                         if (ent->fts_info == FTS_F) {
 383                                 CFRef<CFDataRef> hash;
 384                                 if (files2)     // try to get the hash from a previously-made version
 385                                         if (CFTypeRef seal = CFDictionaryGetValue(files2, CFTempString(relpath))) {
 386                                                 if (CFGetTypeID(seal) == CFDataGetTypeID())
 387                                                         hash = CFDataRef(seal);
 388                                                 else
 389                                                         hash = CFDataRef(CFDictionaryGetValue(CFDictionaryRef(seal), CFSTR("hash")));
 390                                         }
 391                                 if (!hash)
 392                                         hash.take(resources.hashFile(ent->fts_accpath, kSecCodeSignatureHashSHA1));
 393                                 if (ruleFlags == 0) {   // default case - plain hash
 394                                         cfadd(files, "{%s=%O}", relpath.c_str(), hash.get());
 395                                         secdebug("csresource", "%s added simple (rule %p)", relpath.c_str(), rule);
 396                                 } else {        // more complicated - use a sub-dictionary
 397                                         cfadd(files, "{%s={hash=%O,optional=%B}}",
 398                                                 relpath.c_str(), hash.get(), ruleFlags & ResourceBuilder::optional);
 399                                         secdebug("csresource", "%s added complex (rule %p)", relpath.c_str(), rule);
 400                                 }
 401                         }
 402                 });
 403                 CFDictionaryAddValue(result, CFSTR("files"), files.get());
 404         }
 405
 406         resourceDirectory = result.get();
 407         resourceDictData.take(makeCFData(resourceDirectory.get()));
 408 }
 409
 410
 411 //
 412 // Deal with one piece of nested code
 413 //
 414 CFMutableDictionaryRef SecCodeSigner::Signer::signNested(const std::string &path, const std::string &relpath)
 415 {
 416         // sign nested code and collect nesting information
 417         try {
 418                 SecPointer<SecStaticCode> code = new SecStaticCode(DiskRep::bestGuess(path));
 419                 if (signingFlags() & kSecCSSignNestedCode)
 420                         this->state.sign(code, signingFlags());
 421                 std::string dr = Dumper::dump(code->designatedRequirement());
 422                 return cfmake<CFMutableDictionaryRef>("{requirement=%s,cdhash=%O}",
 423                         Dumper::dump(code->designatedRequirement()).c_str(),
 424                         code->cdHash());
 425         } catch (const CommonError &err) {
 426                 CSError::throwMe(err.osStatus(), kSecCFErrorPath, CFTempURL(relpath, false, this->code->resourceBase()));
 427         }
 428 }
 429
 430
 431 //
 432 // Sign a Mach-O binary, using liberal dollops of that special Mach-O magic sauce.
 433 // Note that this will deal just fine with non-fat Mach-O binaries, but it will
 434 // treat them as architectural binaries containing (only) one architecture - that
 435 // interpretation is courtesy of the Universal/MachO support classes.
 436 //
 437 void SecCodeSigner::Signer::signMachO(Universal *fat, const Requirement::Context &context)
 438 {
 439         // Mach-O executable at the core - perform multi-architecture signing
 440         auto_ptr<ArchEditor> editor(state.mDetached
 441                 ? static_cast<ArchEditor *>(new BlobEditor(*fat, *this))
 442                 : new MachOEditor(rep->writer(), *fat, this->digestAlgorithms(), rep->mainExecutablePath()));
 443         assert(editor->count() > 0);
 444         if (!editor->attribute(writerNoGlobal)) // can store architecture-common components
 445                 populate(*editor);
 446
 447         // pass 1: prepare signature blobs and calculate sizes
 448         for (MachOEditor::Iterator it = editor->begin(); it != editor->end(); ++it) {
 449                 MachOEditor::Arch &arch = *it->second;
 450                 arch.source.reset(fat->architecture(it->first));
 451
 452                 // library validation is not compatible with i386
 453                 if (arch.architecture.cpuType() == CPU_TYPE_I386) {
 454                         if (cdFlags & kSecCodeSignatureLibraryValidation) {
 455                                 MacOSError::throwMe(errSecCSBadLVArch);
 456                         }
 457                 }
 458
 459                 arch.ireqs(requirements, rep->defaultRequirements(&arch.architecture, *this), context);
 460                 if (editor->attribute(writerNoGlobal))  // can't store globally, add per-arch
 461                         populate(arch);
 462                 for (auto type = digestAlgorithms().begin(); type != digestAlgorithms().end(); ++type) {
 463                         arch.eachDigest(^(CodeDirectory::Builder& builder) {
 464                                 populate(builder, arch, arch.ireqs,
 465                                                  arch.source->offset(), arch.source->signingExtent(), unsigned(digestAlgorithms().size()-1));
 466                         });
 467                 }
 468
 469                 // add identification blob (made from this architecture) only if we're making a detached signature
 470                 if (state.mDetached) {
 471                         CFRef<CFDataRef> identification = MachORep::identificationFor(arch.source.get());
 472                         arch.add(cdIdentificationSlot, BlobWrapper::alloc(
 473                                 CFDataGetBytePtr(identification), CFDataGetLength(identification)));
 474                 }
 475
 476                 // prepare SuperBlob size estimate
 477                 __block std::vector<size_t> sizes;
 478                 arch.eachDigest(^(CodeDirectory::Builder& builder){
 479                         sizes.push_back(builder.size(CodeDirectory::currentVersion));
 480                 });
 481                 arch.blobSize = arch.size(sizes, state.mCMSSize, 0);
 482         }
 483
 484         editor->allocate();
 485
 486         // pass 2: Finish and generate signatures, and write them
 487         for (MachOEditor::Iterator it = editor->begin(); it != editor->end(); ++it) {
 488                 MachOEditor::Arch &arch = *it->second;
 489                 editor->reset(arch);
 490
 491                 // finish CodeDirectories (off new binary) and sign it
 492                 __block CodeDirectorySet cdSet;
 493                 arch.eachDigest(^(CodeDirectory::Builder &builder) {
 494                         CodeDirectory *cd = builder.build();
 495                         cdSet.add(cd);
 496                 });
 497                 CFRef<CFArrayRef> hashes = cdSet.hashBag();
 498                 CFTemp<CFDictionaryRef> hashDict("{cdhashes=%O}", hashes.get());
 499                 CFRef<CFDataRef> hashBag = makeCFData(hashDict.get());
 500                 CFRef<CFDataRef> signature = signCodeDirectory(cdSet.primary(), hashBag);
 501
 502                 // complete the SuperBlob
 503                 cdSet.populate(&arch);
 504                 arch.add(cdSignatureSlot, BlobWrapper::alloc(
 505                         CFDataGetBytePtr(signature), CFDataGetLength(signature)));
 506                 if (!state.mDryRun) {
 507                         EmbeddedSignatureBlob *blob = arch.make();
 508                         editor->write(arch, blob);      // takes ownership of blob
 509                 }
 510         }
 511
 512         // done: write edit copy back over the original
 513         if (!state.mDryRun)
 514                 editor->commit();
 515 }
 516
 517
 518 //
 519 // Sign a binary that has no notion of architecture.
 520 // That currently means anything that isn't Mach-O format.
 521 //
 522 void SecCodeSigner::Signer::signArchitectureAgnostic(const Requirement::Context &context)
 523 {
 524         // non-Mach-O executable - single-instance signing
 525         RefPointer<DiskRep::Writer> writer = state.mDetached ?
 526                 (new DetachedBlobWriter(*this)) : rep->writer();
 527
 528         CodeDirectorySet cdSet;
 529         for (auto type = digestAlgorithms().begin(); type != digestAlgorithms().end(); ++type) {
 530                 CodeDirectory::Builder builder(*type);
 531                 InternalRequirements ireqs;
 532                 ireqs(requirements, rep->defaultRequirements(NULL, *this), context);
 533                 populate(*writer);
 534                 populate(builder, *writer, ireqs, rep->signingBase(), rep->signingLimit(), unsigned(digestAlgorithms().size()-1));
 535
 536                 CodeDirectory *cd = builder.build();
 537                 if (!state.mDryRun)
 538                         cdSet.add(cd);
 539         }
 540
 541         // add identification blob (made from this architecture) only if we're making a detached signature
 542         if (state.mDetached) {
 543                 CFRef<CFDataRef> identification = rep->identification();
 544                 writer->component(cdIdentificationSlot, identification);
 545         }
 546
 547         // write out all CodeDirectories
 548         cdSet.populate(writer);
 549         writer->flush();
 550
 551         CFRef<CFArrayRef> hashes = cdSet.hashBag();
 552         CFTemp<CFDictionaryRef> hashDict("{cdhashes=%O}", hashes.get());
 553         CFRef<CFDataRef> hashBag = makeCFData(hashDict.get());
 554         CFRef<CFDataRef> signature = signCodeDirectory(cdSet.primary(), hashBag);
 555         writer->signature(signature);
 556 }
 557
 558
 559 //
 560 // Global populate - send components to destination buffers ONCE
 561 //
 562 void SecCodeSigner::Signer::populate(DiskRep::Writer &writer)
 563 {
 564         if (resourceDirectory && !state.mDryRun)
 565                 writer.component(cdResourceDirSlot, resourceDictData);
 566 }
 567
 568
 569 //
 570 // Per-architecture populate - send components to per-architecture buffers
 571 // and populate the CodeDirectory for an architecture. In architecture-agnostic
 572 // signing operations, the non-architectural binary is considered one (arbitrary) architecture
 573 // for the purposes of this call.
 574 //
 575 void SecCodeSigner::Signer::populate(CodeDirectory::Builder &builder, DiskRep::Writer &writer,
 576         InternalRequirements &ireqs, size_t offset, size_t length, unsigned alternateDigestCount)
 577 {
 578         // fill the CodeDirectory
 579         builder.executable(rep->mainExecutablePath(), pagesize, offset, length);
 580         builder.flags(cdFlags);
 581         builder.identifier(identifier);
 582         builder.teamID(teamID);
 583         builder.platform(state.mPlatform);
 584
 585         if (CFRef<CFDataRef> data = rep->component(cdInfoSlot))
 586                 builder.specialSlot(cdInfoSlot, data);
 587         if (ireqs) {
 588                 CFRef<CFDataRef> data = makeCFData(*ireqs);
 589                 writer.component(cdRequirementsSlot, data);
 590                 builder.specialSlot(cdRequirementsSlot, data);
 591         }
 592         if (resourceDirectory)
 593                 builder.specialSlot(cdResourceDirSlot, resourceDictData);
 594         if (entitlements) {
 595                 writer.component(cdEntitlementSlot, entitlements);
 596                 builder.specialSlot(cdEntitlementSlot, entitlements);
 597         }
 598         if (CFRef<CFDataRef> repSpecific = rep->component(cdRepSpecificSlot))
 599                 builder.specialSlot(cdRepSpecificSlot, repSpecific);
 600
 601         writer.addDiscretionary(builder);
 602
 603         if ((signingFlags() & (kSecCSSignOpaque|kSecCSSignV1)) == 0) {
 604                 // calculate sorted list of top SuperBlob keys in this EmbeddedSignatureBlob (if any)
 605                 // (but not for opaque or V1 construction, which must remain bit-for-bit compatible)
 606                 std::vector<Endian<uint32_t> > slotVector;
 607                 slotVector.push_back(cdCodeDirectorySlot);      // mandatory
 608                 std::set<CodeDirectory::Slot> filledSlots = builder.filledSpecialSlots();
 609                 filledSlots.insert(cdTopDirectorySlot);         // will be added below
 610                 copy(filledSlots.begin(), filledSlots.end(), back_inserter(slotVector));
 611                 for (unsigned n = 0; n < alternateDigestCount; n++)
 612                         slotVector.push_back(cdAlternateCodeDirectorySlots + n);
 613                 slotVector.push_back(cdSignatureSlot);
 614                 CFTempData cfSlotVector(&slotVector[0], slotVector.size() * sizeof(slotVector[0]));
 615                 writer.component(cdTopDirectorySlot, cfSlotVector);
 616                 builder.specialSlot(cdTopDirectorySlot, cfSlotVector);
 617         }
 618 }
 619
 620
 621 #include <security_smime/tsaSupport.h>
 622
 623 //
 624 // Generate the CMS signature for a (finished) CodeDirectory.
 625 //
 626 CFDataRef SecCodeSigner::Signer::signCodeDirectory(const CodeDirectory *cd, CFDataRef hashBag)
 627 {
 628         assert(state.mSigner);
 629         CFRef<CFMutableDictionaryRef> defaultTSContext = NULL;
 630
 631         // a null signer generates a null signature blob
 632         if (state.mSigner == SecIdentityRef(kCFNull))
 633                 return CFDataCreate(NULL, NULL, 0);
 634
 635         // generate CMS signature
 636         CFRef<CMSEncoderRef> cms;
 637         MacOSError::check(CMSEncoderCreate(&cms.aref()));
 638         MacOSError::check(CMSEncoderSetCertificateChainMode(cms, kCMSCertificateChainWithRoot));
 639         CMSEncoderAddSigners(cms, state.mSigner);
 640         CMSEncoderSetSignerAlgorithm(cms, kCMSEncoderDigestAlgorithmSHA256);
 641         MacOSError::check(CMSEncoderSetHasDetachedContent(cms, true));
 642
 643         if (signingTime) {
 644                 MacOSError::check(CMSEncoderAddSignedAttributes(cms, kCMSAttrSigningTime));
 645                 MacOSError::check(CMSEncoderSetSigningTime(cms, signingTime));
 646         }
 647
 648         if (hashBag) {
 649                 MacOSError::check(CMSEncoderAddSignedAttributes(cms, kCMSAttrAppleCodesigningHashAgility));
 650                 MacOSError::check(CMSEncoderSetAppleCodesigningHashAgility(cms, hashBag));
 651         }
 652
 653         MacOSError::check(CMSEncoderUpdateContent(cms, cd, cd->length()));
 654
 655     // Set up to call Timestamp server if requested
 656     if (state.mWantTimeStamp)
 657     {
 658         CFRef<CFErrorRef> error = NULL;
 659         defaultTSContext = SecCmsTSAGetDefaultContext(&error.aref());
 660         if (error)
 661             MacOSError::throwMe(errSecDataNotAvailable);
 662
 663         if (state.mNoTimeStampCerts || state.mTimestampService) {
 664             if (state.mTimestampService)
 665                 CFDictionarySetValue(defaultTSContext, kTSAContextKeyURL, state.mTimestampService);
 666             if (state.mNoTimeStampCerts)
 667                 CFDictionarySetValue(defaultTSContext, kTSAContextKeyNoCerts, kCFBooleanTrue);
 668                 }
 669
 670                 CmsMessageSetTSAContext(cms, defaultTSContext);
 671     }
 672
 673         CFDataRef signature;
 674         MacOSError::check(CMSEncoderCopyEncodedContent(cms, &signature));
 675
 676         return signature;
 677 }
 678
 679
 680 //
 681 // Our DiskRep::signingContext methods communicate with the signing subsystem
 682 // in terms those callers can easily understand.
 683 //
 684 string SecCodeSigner::Signer::sdkPath(const std::string &path) const
 685 {
 686         assert(path[0] == '/'); // need absolute path here
 687         if (state.mSDKRoot)
 688                 return cfString(state.mSDKRoot) + path;
 689         else
 690                 return path;
 691 }
 692
 693 bool SecCodeSigner::Signer::isAdhoc() const
 694 {
 695         return state.mSigner == SecIdentityRef(kCFNull);
 696 }
 697
 698 SecCSFlags SecCodeSigner::Signer::signingFlags() const
 699 {
 700         return state.mOpFlags;
 701 }
 702
 703
 704 //
 705 // Parse a text of the form
 706 //      flag,...,flag
 707 // where each flag is the canonical name of a signable CodeDirectory flag.
 708 // No abbreviations are allowed, and internally set flags are not accepted.
 709 //
 710 uint32_t SecCodeSigner::Signer::cdTextFlags(std::string text)
 711 {
 712         uint32_t flags = 0;
 713         for (string::size_type comma = text.find(','); ; text = text.substr(comma+1), comma = text.find(',')) {
 714                 string word = (comma == string::npos) ? text : text.substr(0, comma);
 715                 const SecCodeDirectoryFlagTable *item;
 716                 for (item = kSecCodeDirectoryFlagTable; item->name; item++)
 717                         if (item->signable && word == item->name) {
 718                                 flags |= item->value;
 719                                 break;
 720                         }
 721                 if (!item->name)        // not found
 722                         MacOSError::throwMe(errSecCSInvalidFlags);
 723                 if (comma == string::npos)      // last word
 724                         break;
 725         }
 726         return flags;
 727 }
 728
 729
 730 //
 731 // Generate a unique string from our underlying DiskRep.
 732 // We could get 90%+ of the uniquing benefit by just generating
 733 // a random string here. Instead, we pick the (hex string encoding of)
 734 // the source rep's unique identifier blob. For universal binaries,
 735 // this is the canonical local architecture, which is a bit arbitrary.
 736 // This provides us with a consistent unique string for all architectures
 737 // of a fat binary, *and* (unlike a random string) is reproducible
 738 // for identical inputs, even upon resigning.
 739 //
 740 std::string SecCodeSigner::Signer::uniqueName() const
 741 {
 742         CFRef<CFDataRef> identification = rep->identification();
 743         const UInt8 *ident = CFDataGetBytePtr(identification);
 744         const CFIndex length = CFDataGetLength(identification);
 745         string result;
 746         for (CFIndex n = 0; n < length; n++) {
 747                 char hex[3];
 748                 snprintf(hex, sizeof(hex), "%02x", ident[n]);
 749                 result += hex;
 750         }
 751         return result;
 752 }
 753
 754
 755 } // end namespace CodeSigning
 756 } // end namespace Security