Security-57031.30.12.tar.gz

[apple/security.git] / Security / libsecurity_codesigning / lib / StaticCode.cpp

/*
 * Copyright (c) 2006-2014 Apple Inc. All Rights Reserved.
 * 
 * @APPLE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this
 * file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */

//
// StaticCode - SecStaticCode API objects
//
#include "StaticCode.h"
#include "Code.h"
#include "reqmaker.h"
#include "drmaker.h"
#include "reqdumper.h"
#include "reqparser.h"
#include "sigblob.h"
#include "resources.h"
#include "detachedrep.h"
#include "csdatabase.h"
#include "dirscanner.h"
#include <CoreFoundation/CFURLAccess.h>
#include <Security/SecPolicyPriv.h>
#include <Security/SecTrustPriv.h>
#include <Security/SecCertificatePriv.h>
#include <Security/CMSPrivate.h>
#include <Security/SecCmsContentInfo.h>
#include <Security/SecCmsSignerInfo.h>
#include <Security/SecCmsSignedData.h>
#include <Security/cssmapplePriv.h>
#include <security_utilities/unix++.h>
#include <security_utilities/cfmunge.h>
#include <Security/CMSDecoder.h>
#include <security_utilities/logging.h>
#include <dirent.h>
#include <sstream>
#include <IOKit/storage/IOStorageDeviceCharacteristics.h>


namespace Security {
namespace CodeSigning {

using namespace UnixPlusPlus;

// A requirement representing a Mac or iOS dev cert, a Mac or iOS distribution cert, or a developer ID
static const char WWDRRequirement[] = "anchor apple generic and certificate leaf[field.1.2.840.113635.100.6.1.2] exists";
static const char MACWWDRRequirement[] = "anchor apple generic and certificate leaf[field.1.2.840.113635.100.6.1.12] exists";
static const char developerID[] = "anchor apple generic and certificate 1[field.1.2.840.113635.100.6.2.6] exists"
											" and certificate leaf[field.1.2.840.113635.100.6.1.13] exists";
static const char distributionCertificate[] =	"anchor apple generic and certificate leaf[field.1.2.840.113635.100.6.1.7] exists";
static const char iPhoneDistributionCert[] =	"anchor apple generic and certificate leaf[field.1.2.840.113635.100.6.1.4] exists";

//
// Map a component slot number to a suitable error code for a failure
//
static inline OSStatus errorForSlot(CodeDirectory::SpecialSlot slot)
{
	switch (slot) {
	case cdInfoSlot:
		return errSecCSInfoPlistFailed;
	case cdResourceDirSlot:
		return errSecCSResourceDirectoryFailed;
	default:
		return errSecCSSignatureFailed;
	}
}


//
// Construct a SecStaticCode object given a disk representation object
//
SecStaticCode::SecStaticCode(DiskRep *rep)
	: mRep(rep),
	  mValidated(false), mExecutableValidated(false), mResourcesValidated(false), mResourcesValidContext(NULL),
	  mProgressQueue("com.apple.security.validation-progress", false, DISPATCH_QUEUE_PRIORITY_DEFAULT),
	  mDesignatedReq(NULL), mGotResourceBase(false), mMonitor(NULL), mLimitedAsync(NULL), mEvalDetails(NULL)
{
	CODESIGN_STATIC_CREATE(this, rep);
	CFRef<CFDataRef> codeDirectory = rep->codeDirectory();
	if (codeDirectory && CFDataGetLength(codeDirectory) <= 0)
		MacOSError::throwMe(errSecCSSignatureInvalid);
	checkForSystemSignature();
}


//
// Clean up a SecStaticCode object
//
SecStaticCode::~SecStaticCode() throw()
try {
	::free(const_cast<Requirement *>(mDesignatedReq));
	delete mResourcesValidContext;
	delete mLimitedAsync;
} catch (...) {
	return;
}

//
// Initialize a nested SecStaticCode object from its parent
//
void SecStaticCode::initializeFromParent(const SecStaticCode& parent) {
	setMonitor(parent.monitor());
	if (parent.mLimitedAsync)
		mLimitedAsync = new LimitedAsync(*parent.mLimitedAsync);
}

//
// CF-level comparison of SecStaticCode objects compares CodeDirectory hashes if signed,
// and falls back on comparing canonical paths if (both are) not.
//
bool SecStaticCode::equal(SecCFObject &secOther)
{
	SecStaticCode *other = static_cast<SecStaticCode *>(&secOther);
	CFDataRef mine = this->cdHash();
	CFDataRef his = other->cdHash();
	if (mine || his)
		return mine && his && CFEqual(mine, his);
	else
		return CFEqual(CFRef<CFURLRef>(this->copyCanonicalPath()), CFRef<CFURLRef>(other->copyCanonicalPath()));
}

CFHashCode SecStaticCode::hash()
{
	if (CFDataRef h = this->cdHash())
		return CFHash(h);
	else
		return CFHash(CFRef<CFURLRef>(this->copyCanonicalPath()));
}


//
// Invoke a stage monitor if registered
//
CFTypeRef SecStaticCode::reportEvent(CFStringRef stage, CFDictionaryRef info)
{
	if (mMonitor)
		return mMonitor(this->handle(false), stage, info);
	else
		return NULL;
}

void SecStaticCode::prepareProgress(unsigned int workload)
{
	dispatch_sync(mProgressQueue, ^{
		mCancelPending = false;			// not cancelled
	});
	if (mValidationFlags & kSecCSReportProgress) {
		mCurrentWork = 0;				// nothing done yet
		mTotalWork = workload;			// totally fake - we don't know how many files we'll get to chew
	}
}

void SecStaticCode::reportProgress(unsigned amount /* = 1 */)
{
	if (mMonitor && (mValidationFlags & kSecCSReportProgress)) {
		// update progress and report
		__block bool cancel = false;
		dispatch_sync(mProgressQueue, ^{
			if (mCancelPending)
				cancel = true;
			mCurrentWork += amount;
			mMonitor(this->handle(false), CFSTR("progress"), CFTemp<CFDictionaryRef>("{current=%d,total=%d}", mCurrentWork, mTotalWork));
		});
		// if cancellation is pending, abort now
		if (cancel)
			MacOSError::throwMe(errSecCSCancelled);
	}
}


//
// Set validation conditions for fine-tuning legacy tolerance
//
static void addError(CFTypeRef cfError, void* context)
{
	if (CFGetTypeID(cfError) == CFNumberGetTypeID()) {
		int64_t error;
		CFNumberGetValue(CFNumberRef(cfError), kCFNumberSInt64Type, (void*)&error);
		MacOSErrorSet* errors = (MacOSErrorSet*)context;
		errors->insert(OSStatus(error));
	}
}

void SecStaticCode::setValidationModifiers(CFDictionaryRef conditions)
{
	if (conditions) {
		CFDictionary source(conditions, errSecCSDbCorrupt);
		mAllowOmissions = source.get<CFArrayRef>("omissions");
		if (CFArrayRef errors = source.get<CFArrayRef>("errors"))
			CFArrayApplyFunction(errors, CFRangeMake(0, CFArrayGetCount(errors)), addError, &this->mTolerateErrors);
	}
}

	
//
// Request cancellation of a validation in progress.
// We do this by posting an abort flag that is checked periodically.
//
void SecStaticCode::cancelValidation()
{
	if (!(mValidationFlags & kSecCSReportProgress))		// not using progress reporting; cancel won't make it through
		MacOSError::throwMe(errSecCSInvalidFlags);
	dispatch_sync(mProgressQueue, ^{
		mCancelPending = true;
	});
}


//
// Attach a detached signature.
//
void SecStaticCode::detachedSignature(CFDataRef sigData)
{
	if (sigData) {
		mDetachedSig = sigData;
		mRep = new DetachedRep(sigData, mRep->base(), "explicit detached");
		CODESIGN_STATIC_ATTACH_EXPLICIT(this, mRep);
	} else {
		mDetachedSig = NULL;
		mRep = mRep->base();
		CODESIGN_STATIC_ATTACH_EXPLICIT(this, NULL);
	}
}


//
// Consult the system detached signature database to see if it contains
// a detached signature for this StaticCode. If it does, fetch and attach it.
// We do this only if the code has no signature already attached.
//
void SecStaticCode::checkForSystemSignature()
{
	if (!this->isSigned()) {
		SignatureDatabase db;
		if (db.isOpen())
			try {
				if (RefPointer<DiskRep> dsig = db.findCode(mRep)) {
					CODESIGN_STATIC_ATTACH_SYSTEM(this, dsig);
					mRep = dsig;
				}
			} catch (...) {
			}
	}
}


//
// Return a descriptive string identifying the source of the code signature
//
string SecStaticCode::signatureSource()
{
	if (!isSigned())
		return "unsigned";
	if (DetachedRep *rep = dynamic_cast<DetachedRep *>(mRep.get()))
		return rep->source();
	return "embedded";
}


//
// Do ::required, but convert incoming SecCodeRefs to their SecStaticCodeRefs
// (if possible).
//
SecStaticCode *SecStaticCode::requiredStatic(SecStaticCodeRef ref)
{
	SecCFObject *object = SecCFObject::required(ref, errSecCSInvalidObjectRef);
	if (SecStaticCode *scode = dynamic_cast<SecStaticCode *>(object))
		return scode;
	else if (SecCode *code = dynamic_cast<SecCode *>(object))
		return code->staticCode();
	else	// neither (a SecSomethingElse)
		MacOSError::throwMe(errSecCSInvalidObjectRef);
}

SecCode *SecStaticCode::optionalDynamic(SecStaticCodeRef ref)
{
	SecCFObject *object = SecCFObject::required(ref, errSecCSInvalidObjectRef);
	if (dynamic_cast<SecStaticCode *>(object))
		return NULL;
	else if (SecCode *code = dynamic_cast<SecCode *>(object))
		return code;
	else	// neither (a SecSomethingElse)
		MacOSError::throwMe(errSecCSInvalidObjectRef);
}


//
// Void all cached validity data.
//
// We also throw out cached components, because the new signature data may have
// a different idea of what components should be present. We could reconcile the
// cached data instead, if performance seems to be impacted.
//
void SecStaticCode::resetValidity()
{
	CODESIGN_EVAL_STATIC_RESET(this);
	mValidated = false;
	mExecutableValidated = mResourcesValidated = false;
	if (mResourcesValidContext) {
		delete mResourcesValidContext;
		mResourcesValidContext = NULL;
	}
	mDir = NULL;
	mSignature = NULL;
	for (unsigned n = 0; n < cdSlotCount; n++)
		mCache[n] = NULL;
	mInfoDict = NULL;
	mEntitlements = NULL;
	mResourceDict = NULL;
	mDesignatedReq = NULL;
	mCDHash = NULL;
	mGotResourceBase = false;
	mTrust = NULL;
	mCertChain = NULL;
	mEvalDetails = NULL;
	mRep->flush();
	
	// we may just have updated the system database, so check again
	checkForSystemSignature();
}


//
// Retrieve a sealed component by special slot index.
// If the CodeDirectory has already been validated, validate against that.
// Otherwise, retrieve the component without validation (but cache it). Validation
// will go through the cache and validate all cached components.
//
CFDataRef SecStaticCode::component(CodeDirectory::SpecialSlot slot, OSStatus fail /* = errSecCSSignatureFailed */)
{
	assert(slot <= cdSlotMax);
	
	CFRef<CFDataRef> &cache = mCache[slot];
	if (!cache) {
		if (CFRef<CFDataRef> data = mRep->component(slot)) {
			if (validated()) // if the directory has been validated...
				if (!codeDirectory()->validateSlot(CFDataGetBytePtr(data), // ... and it's no good
						CFDataGetLength(data), -slot))
					MacOSError::throwMe(errorForSlot(slot)); // ... then bail
			cache = data;	// it's okay, cache it
		} else {	// absent, mark so
			if (validated())	// if directory has been validated...
				if (codeDirectory()->slotIsPresent(-slot)) // ... and the slot is NOT missing
					MacOSError::throwMe(errorForSlot(slot));	// was supposed to be there
			cache = CFDataRef(kCFNull);		// white lie
		}
	}
	return (cache == CFDataRef(kCFNull)) ? NULL : cache.get();
}


//
// Get the CodeDirectory.
// Throws (if check==true) or returns NULL (check==false) if there is none.
// Always throws if the CodeDirectory exists but is invalid.
// NEVER validates against the signature.
//
const CodeDirectory *SecStaticCode::codeDirectory(bool check /* = true */)
{
	if (!mDir) {
		if (mDir.take(mRep->codeDirectory())) {
			const CodeDirectory *dir = reinterpret_cast<const CodeDirectory *>(CFDataGetBytePtr(mDir));
			dir->checkIntegrity();
		}
	}
	if (mDir)
		return reinterpret_cast<const CodeDirectory *>(CFDataGetBytePtr(mDir));
	if (check)
		MacOSError::throwMe(errSecCSUnsigned);
	return NULL;
}


//
// Get the hash of the CodeDirectory.
// Returns NULL if there is none.
//
CFDataRef SecStaticCode::cdHash()
{
	if (!mCDHash) {
		if (const CodeDirectory *cd = codeDirectory(false)) {
			SHA1 hash;
			hash(cd, cd->length());
			SHA1::Digest digest;
			hash.finish(digest);
			mCDHash.take(makeCFData(digest, sizeof(digest)));
			CODESIGN_STATIC_CDHASH(this, digest, sizeof(digest));
		}
	}
	return mCDHash;
}


//
// Return the CMS signature blob; NULL if none found.
//
CFDataRef SecStaticCode::signature()
{
	if (!mSignature)
		mSignature.take(mRep->signature());
	if (mSignature)
		return mSignature;
	MacOSError::throwMe(errSecCSUnsigned);
}


//
// Verify the signature on the CodeDirectory.
// If this succeeds (doesn't throw), the CodeDirectory is statically trustworthy.
// Any outcome (successful or not) is cached for the lifetime of the StaticCode.
//
void SecStaticCode::validateDirectory()
{
	// echo previous outcome, if any
	// track revocation separately, as it may not have been checked
	// during the initial validation
	if (!validated() || ((mValidationFlags & kSecCSEnforceRevocationChecks) && !revocationChecked()))
		try {
			// perform validation (or die trying)
			CODESIGN_EVAL_STATIC_DIRECTORY(this);
			mValidationExpired = verifySignature();
			if (mValidationFlags & kSecCSEnforceRevocationChecks)
				mRevocationChecked = true;

			for (CodeDirectory::SpecialSlot slot = codeDirectory()->maxSpecialSlot(); slot >= 1; --slot)
				if (mCache[slot])	// if we already loaded that resource...
					validateComponent(slot, errorForSlot(slot)); // ... then check it now
			mValidated = true;			// we've done the deed...
			mValidationResult = errSecSuccess;	// ... and it was good
		} catch (const CommonError &err) {
			mValidated = true;
			mValidationResult = err.osStatus();
			throw;
		} catch (...) {
			secdebug("staticCode", "%p validation threw non-common exception", this);
			mValidated = true;
			mValidationResult = errSecCSInternalError;
			throw;
		}
	assert(validated());
	if (mValidationResult == errSecSuccess) {
		if (mValidationExpired)
			if ((mValidationFlags & kSecCSConsiderExpiration)
					|| (codeDirectory()->flags & kSecCodeSignatureForceExpiration))
				MacOSError::throwMe(CSSMERR_TP_CERT_EXPIRED);
	} else
		MacOSError::throwMe(mValidationResult);
}


//
// Load and validate the CodeDirectory and all components *except* those related to the resource envelope.
// Those latter components are checked by validateResources().
//
void SecStaticCode::validateNonResourceComponents()
{
	this->validateDirectory();
	for (CodeDirectory::SpecialSlot slot = codeDirectory()->maxSpecialSlot(); slot >= 1; --slot)
		switch (slot) {
		case cdResourceDirSlot:		// validated by validateResources
			break;
		default:
			this->component(slot);		// loads and validates
			break;
		}
}


//
// Get the (signed) signing date from the code signature.
// Sadly, we need to validate the signature to get the date (as a side benefit).
// This means that you can't get the signing time for invalidly signed code.
//
// We could run the decoder "almost to" verification to avoid this, but there seems
// little practical point to such a duplication of effort.
//
CFAbsoluteTime SecStaticCode::signingTime()
{
	validateDirectory();
	return mSigningTime;
}

CFAbsoluteTime SecStaticCode::signingTimestamp()
{
	validateDirectory();
	return mSigningTimestamp;
}


//
// Verify the CMS signature on the CodeDirectory.
// This performs the cryptographic tango. It returns if the signature is valid,
// or throws if it is not. As a side effect, a successful return sets up the
// cached certificate chain for future use.
// Returns true if the signature is expired (the X.509 sense), false if it's not.
// Expiration is fatal (throws) if a secure timestamp is included, but not otherwise.
//
bool SecStaticCode::verifySignature()
{
	// ad-hoc signed code is considered validly signed by definition
	if (flag(kSecCodeSignatureAdhoc)) {
		CODESIGN_EVAL_STATIC_SIGNATURE_ADHOC(this);
		return false;
	}

	DTRACK(CODESIGN_EVAL_STATIC_SIGNATURE, this, (char*)this->mainExecutablePath().c_str());

	// decode CMS and extract SecTrust for verification
	CFRef<CMSDecoderRef> cms;
	MacOSError::check(CMSDecoderCreate(&cms.aref())); // create decoder
	CFDataRef sig = this->signature();
	MacOSError::check(CMSDecoderUpdateMessage(cms, CFDataGetBytePtr(sig), CFDataGetLength(sig)));
	this->codeDirectory();	// load CodeDirectory (sets mDir)
	MacOSError::check(CMSDecoderSetDetachedContent(cms, mDir));
	MacOSError::check(CMSDecoderFinalizeMessage(cms));
	MacOSError::check(CMSDecoderSetSearchKeychain(cms, cfEmptyArray()));
	CFRef<CFArrayRef> vf_policies = verificationPolicies();
    CFRef<CFArrayRef> ts_policies = SecPolicyCreateAppleTimeStampingAndRevocationPolicies(vf_policies);
    CMSSignerStatus status;
    MacOSError::check(CMSDecoderCopySignerStatus(cms, 0, vf_policies,
    false, &status, &mTrust.aref(), NULL));

	if (status != kCMSSignerValid)
		MacOSError::throwMe(errSecCSSignatureFailed);

	// internal signing time (as specified by the signer; optional)
	mSigningTime = 0;       // "not present" marker (nobody could code sign on Jan 1, 2001 :-)
	switch (OSStatus rc = CMSDecoderCopySignerSigningTime(cms, 0, &mSigningTime)) {
	case errSecSuccess:
	case errSecSigningTimeMissing:
		break;
	default:
		MacOSError::throwMe(rc);
	}

	// certified signing time (as specified by a TSA; optional)
	mSigningTimestamp = 0;
	switch (OSStatus rc = CMSDecoderCopySignerTimestampWithPolicy(cms, ts_policies, 0, &mSigningTimestamp)) {
	case errSecSuccess:
	case errSecTimestampMissing:
		break;
	default:
		MacOSError::throwMe(rc);
	}

	// set up the environment for SecTrust
    if (mValidationFlags & kSecCSNoNetworkAccess) {
        MacOSError::check(SecTrustSetNetworkFetchAllowed(mTrust,false)); // no network?
    }
	MacOSError::check(SecTrustSetAnchorCertificates(mTrust, cfEmptyArray())); // no anchors
    MacOSError::check(SecTrustSetKeychains(mTrust, cfEmptyArray())); // no keychains
	CSSM_APPLE_TP_ACTION_DATA actionData = {
		CSSM_APPLE_TP_ACTION_VERSION,	// version of data structure
		CSSM_TP_ACTION_IMPLICIT_ANCHORS	// action flags
	};
	
	for (;;) {	// at most twice
		MacOSError::check(SecTrustSetParameters(mTrust,
			CSSM_TP_ACTION_DEFAULT, CFTempData(&actionData, sizeof(actionData))));
	
		// evaluate trust and extract results
		SecTrustResultType trustResult;
		MacOSError::check(SecTrustEvaluate(mTrust, &trustResult));
		MacOSError::check(SecTrustGetResult(mTrust, &trustResult, &mCertChain.aref(), &mEvalDetails));

		// if this is an Apple developer cert....
		if (teamID() && SecStaticCode::isAppleDeveloperCert(mCertChain)) {
			CFRef<CFStringRef> teamIDFromCert;
			if (CFArrayGetCount(mCertChain) > 0) {
				/* Note that SecCertificateCopySubjectComponent sets the out paramater to NULL if there is no field present */
				MacOSError::check(SecCertificateCopySubjectComponent((SecCertificateRef)CFArrayGetValueAtIndex(mCertChain, Requirement::leafCert),
																	 &CSSMOID_OrganizationalUnitName,
																	 &teamIDFromCert.aref()));

				if (teamIDFromCert) {
					CFRef<CFStringRef> teamIDFromCD = CFStringCreateWithCString(NULL, teamID(), kCFStringEncodingUTF8);
					if (!teamIDFromCD) {
						MacOSError::throwMe(errSecCSInternalError);
					}

					if (CFStringCompare(teamIDFromCert, teamIDFromCD, 0) != kCFCompareEqualTo) {
						Security::Syslog::error("Team identifier in the signing certificate (%s) does not match the team identifier (%s) in the code directory", cfString(teamIDFromCert).c_str(), teamID());
						MacOSError::throwMe(errSecCSSignatureInvalid);
					}
				}
			}
		}

		CODESIGN_EVAL_STATIC_SIGNATURE_RESULT(this, trustResult, mCertChain ? (int)CFArrayGetCount(mCertChain) : 0);
		switch (trustResult) {
		case kSecTrustResultProceed:
		case kSecTrustResultUnspecified:
			break;				// success
		case kSecTrustResultDeny:
			MacOSError::throwMe(CSSMERR_APPLETP_TRUST_SETTING_DENY);	// user reject
		case kSecTrustResultInvalid:
			assert(false);		// should never happen
			MacOSError::throwMe(CSSMERR_TP_NOT_TRUSTED);
		default:
			{
				OSStatus result;
				MacOSError::check(SecTrustGetCssmResultCode(mTrust, &result));
				// if we have a valid timestamp, CMS validates against (that) signing time and all is well.
				// If we don't have one, may validate against *now*, and must be able to tolerate expiration.
				if (mSigningTimestamp == 0) // no timestamp available
					if (((result == CSSMERR_TP_CERT_EXPIRED) || (result == CSSMERR_TP_CERT_NOT_VALID_YET))
							&& !(actionData.ActionFlags & CSSM_TP_ACTION_ALLOW_EXPIRED)) {
						CODESIGN_EVAL_STATIC_SIGNATURE_EXPIRED(this);
						actionData.ActionFlags |= CSSM_TP_ACTION_ALLOW_EXPIRED; // (this also allows postdated certs)
						continue;		// retry validation while tolerating expiration
					}
				MacOSError::throwMe(result);
			}
		}
		
		if (mSigningTimestamp) {
			CFIndex rootix = CFArrayGetCount(mCertChain);
			if (SecCertificateRef mainRoot = SecCertificateRef(CFArrayGetValueAtIndex(mCertChain, rootix-1)))
				if (isAppleCA(mainRoot)) {
					// impose policy: if the signature itself draws to Apple, then so must the timestamp signature
					CFRef<CFArrayRef> tsCerts;
					MacOSError::check(CMSDecoderCopySignerTimestampCertificates(cms, 0, &tsCerts.aref()));
					CFIndex tsn = CFArrayGetCount(tsCerts);
					bool good = tsn > 0 && isAppleCA(SecCertificateRef(CFArrayGetValueAtIndex(tsCerts, tsn-1)));
					if (!good)
						MacOSError::throwMe(CSSMERR_TP_NOT_TRUSTED);
				}
		}
		
		return actionData.ActionFlags & CSSM_TP_ACTION_ALLOW_EXPIRED;
	}
}


//
// Return the TP policy used for signature verification.
// This may be a simple SecPolicyRef or a CFArray of policies.
// The caller owns the return value.
//
static SecPolicyRef makeCRLPolicy()
{
	CFRef<SecPolicyRef> policy;
	MacOSError::check(SecPolicyCopy(CSSM_CERT_X_509v3, &CSSMOID_APPLE_TP_REVOCATION_CRL, &policy.aref()));
	CSSM_APPLE_TP_CRL_OPTIONS options;
	memset(&options, 0, sizeof(options));
	options.Version = CSSM_APPLE_TP_CRL_OPTS_VERSION;
	options.CrlFlags = CSSM_TP_ACTION_FETCH_CRL_FROM_NET | CSSM_TP_ACTION_CRL_SUFFICIENT;
	CSSM_DATA optData = { sizeof(options), (uint8 *)&options };
	MacOSError::check(SecPolicySetValue(policy, &optData));
	return policy.yield();
}

static SecPolicyRef makeOCSPPolicy()
{
	CFRef<SecPolicyRef> policy;
	MacOSError::check(SecPolicyCopy(CSSM_CERT_X_509v3, &CSSMOID_APPLE_TP_REVOCATION_OCSP, &policy.aref()));
	CSSM_APPLE_TP_OCSP_OPTIONS options;
	memset(&options, 0, sizeof(options));
	options.Version = CSSM_APPLE_TP_OCSP_OPTS_VERSION;
	options.Flags = CSSM_TP_ACTION_OCSP_SUFFICIENT;
	CSSM_DATA optData = { sizeof(options), (uint8 *)&options };
	MacOSError::check(SecPolicySetValue(policy, &optData));
	return policy.yield();
}

CFArrayRef SecStaticCode::verificationPolicies()
{
	CFRef<SecPolicyRef> core;
	MacOSError::check(SecPolicyCopy(CSSM_CERT_X_509v3,
			&CSSMOID_APPLE_TP_CODE_SIGNING, &core.aref()));
    if (mValidationFlags & kSecCSNoNetworkAccess) {
        // Skips all revocation since they require network connectivity
        // therefore annihilates kSecCSEnforceRevocationChecks if present
        CFRef<SecPolicyRef> no_revoc = SecPolicyCreateRevocation(kSecRevocationNetworkAccessDisabled);
        return makeCFArray(2, core.get(), no_revoc.get());
    }
	else if (mValidationFlags & kSecCSEnforceRevocationChecks) {
        // Add CRL and OCSPPolicies
		CFRef<SecPolicyRef> crl = makeCRLPolicy();
		CFRef<SecPolicyRef> ocsp = makeOCSPPolicy();
		return makeCFArray(3, core.get(), crl.get(), ocsp.get());
	} else {
		return makeCFArray(1, core.get());
	}
}


//
// Validate a particular sealed, cached resource against its (special) CodeDirectory slot.
// The resource must already have been placed in the cache.
// This does NOT perform basic validation.
//
void SecStaticCode::validateComponent(CodeDirectory::SpecialSlot slot, OSStatus fail /* = errSecCSSignatureFailed */)
{
	assert(slot <= cdSlotMax);
	CFDataRef data = mCache[slot];
	assert(data);		// must be cached
	if (data == CFDataRef(kCFNull)) {
		if (codeDirectory()->slotIsPresent(-slot)) // was supposed to be there...
				MacOSError::throwMe(fail);	// ... and is missing
	} else {
		if (!codeDirectory()->validateSlot(CFDataGetBytePtr(data), CFDataGetLength(data), -slot))
			MacOSError::throwMe(fail);
	}
}


//
// Perform static validation of the main executable.
// This reads the main executable from disk and validates it against the
// CodeDirectory code slot array.
// Note that this is NOT an in-memory validation, and is thus potentially
// subject to timing attacks.
//
void SecStaticCode::validateExecutable()
{
	if (!validatedExecutable()) {
		try {
			DTRACK(CODESIGN_EVAL_STATIC_EXECUTABLE, this,
				(char*)this->mainExecutablePath().c_str(), codeDirectory()->nCodeSlots);
			const CodeDirectory *cd = this->codeDirectory();
			if (!cd) 
				MacOSError::throwMe(errSecCSUnsigned);
			AutoFileDesc fd(mainExecutablePath(), O_RDONLY);
			fd.fcntl(F_NOCACHE, true);		// turn off page caching (one-pass)
			if (Universal *fat = mRep->mainExecutableImage())
				fd.seek(fat->archOffset());
			size_t pageSize = cd->pageSize ? (1 << cd->pageSize) : 0;
			size_t remaining = cd->codeLimit;
			for (uint32_t slot = 0; slot < cd->nCodeSlots; ++slot) {
				size_t size = min(remaining, pageSize);
				if (!cd->validateSlot(fd, size, slot)) {
					CODESIGN_EVAL_STATIC_EXECUTABLE_FAIL(this, (int)slot);
					MacOSError::throwMe(errSecCSSignatureFailed);
				}
				remaining -= size;
			}
			mExecutableValidated = true;
			mExecutableValidResult = errSecSuccess;
		} catch (const CommonError &err) {
			mExecutableValidated = true;
			mExecutableValidResult = err.osStatus();
			throw;
		} catch (...) {
			secdebug("staticCode", "%p executable validation threw non-common exception", this);
			mExecutableValidated = true;
			mExecutableValidResult = errSecCSInternalError;
			throw;
		}
	}
	assert(validatedExecutable());
	if (mExecutableValidResult != errSecSuccess)
		MacOSError::throwMe(mExecutableValidResult);
}


//
// Perform static validation of sealed resources and nested code.
//
// This performs a whole-code static resource scan and effectively
// computes a concordance between what's on disk and what's in the ResourceDirectory.
// Any unsanctioned difference causes an error.
//
unsigned SecStaticCode::estimateResourceWorkload()
{
	// workload estimate = number of sealed files
	CFDictionaryRef sealedResources = resourceDictionary();
	CFDictionaryRef files = cfget<CFDictionaryRef>(sealedResources, "files2");
	if (files == NULL)
		files = cfget<CFDictionaryRef>(sealedResources, "files");
	return files ? unsigned(CFDictionaryGetCount(files)) : 0;
}

void SecStaticCode::validateResources(SecCSFlags flags)
{
	// do we have a superset of this requested validation cached?
	bool doit = true;
	if (mResourcesValidated) {	// have cached outcome
		if (!(flags & kSecCSCheckNestedCode) || mResourcesDeep)	// was deep or need no deep scan
			doit = false;
	}

	if (doit) {
		if (mLimitedAsync == NULL) {
			mLimitedAsync = new LimitedAsync(diskRep()->fd().mediumType() == kIOPropertyMediumTypeSolidStateKey);
		}

		try {
			// sanity first
			CFDictionaryRef sealedResources = resourceDictionary();
			if (this->resourceBase())	// disk has resources
				if (sealedResources)
					/* go to work below */;
				else
					MacOSError::throwMe(errSecCSResourcesNotFound);
			else							// disk has no resources
				if (sealedResources)
					MacOSError::throwMe(errSecCSResourcesNotFound);
				else
					return;					// no resources, not sealed - fine (no work)
		
			// found resources, and they are sealed
			DTRACK(CODESIGN_EVAL_STATIC_RESOURCES, this,
				(char*)this->mainExecutablePath().c_str(), 0);
		
			// scan through the resources on disk, checking each against the resourceDirectory
			mResourcesValidContext = new CollectingContext(*this);		// collect all failures in here

			// use V2 resource seal if available, otherwise fall back to V1
			CFDictionaryRef rules;
			CFDictionaryRef files;
			uint32_t version;
			if (CFDictionaryGetValue(sealedResources, CFSTR("files2"))) {	// have V2 signature
				rules = cfget<CFDictionaryRef>(sealedResources, "rules2");
				files = cfget<CFDictionaryRef>(sealedResources, "files2");
				version = 2;
			} else {	// only V1 available
				rules = cfget<CFDictionaryRef>(sealedResources, "rules");
				files = cfget<CFDictionaryRef>(sealedResources, "files");
				version = 1;
			}
			if (!rules || !files)
				MacOSError::throwMe(errSecCSResourcesInvalid);

			// check for weak resource rules
			bool strict = flags & kSecCSStrictValidate;
			if (strict) {
				if (hasWeakResourceRules(rules, version, mAllowOmissions))
					if (mTolerateErrors.find(errSecCSWeakResourceRules) == mTolerateErrors.end())
						MacOSError::throwMe(errSecCSWeakResourceRules);
				if (version == 1)
					if (mTolerateErrors.find(errSecCSWeakResourceEnvelope) == mTolerateErrors.end())
						MacOSError::throwMe(errSecCSWeakResourceEnvelope);
			}

			Dispatch::Group group;
			Dispatch::Group &groupRef = group;  // (into block)

			// scan through the resources on disk, checking each against the resourceDirectory
			__block CFRef<CFMutableDictionaryRef> resourceMap = makeCFMutableDictionary(files);
			string base = cfString(this->resourceBase());
			ResourceBuilder resources(base, base, rules, codeDirectory()->hashType, strict, mTolerateErrors);
			diskRep()->adjustResources(resources);

			resources.scan(^(FTSENT *ent, uint32_t ruleFlags, const string relpath, ResourceBuilder::Rule *rule) {
				CFDictionaryRemoveValue(resourceMap, CFTempString(relpath));
				bool isSymlink = (ent->fts_info == FTS_SL);

				void (^validate)() = ^{
					validateResource(files, relpath, isSymlink, *mResourcesValidContext, flags, version);
					reportProgress();
				};

				mLimitedAsync->perform(groupRef, validate);
			});
			group.wait();	// wait until all async resources have been validated as well

			unsigned leftovers = unsigned(CFDictionaryGetCount(resourceMap));
			if (leftovers > 0) {
				secdebug("staticCode", "%d sealed resource(s) not found in code", int(leftovers));
				CFDictionaryApplyFunction(resourceMap, SecStaticCode::checkOptionalResource, mResourcesValidContext);
			}
			
			// now check for any errors found in the reporting context
			mResourcesValidated = true;
			mResourcesDeep = flags & kSecCSCheckNestedCode;
			if (mResourcesValidContext->osStatus() != errSecSuccess)
				mResourcesValidContext->throwMe();
		} catch (const CommonError &err) {
			mResourcesValidated = true;
			mResourcesDeep = flags & kSecCSCheckNestedCode;
			mResourcesValidResult = err.osStatus();
			throw;
		} catch (...) {
			secdebug("staticCode", "%p executable validation threw non-common exception", this);
			mResourcesValidated = true;
			mResourcesDeep = flags & kSecCSCheckNestedCode;
			mResourcesValidResult = errSecCSInternalError;
			throw;
		}
	}
	assert(validatedResources());
	if (mResourcesValidResult)
		MacOSError::throwMe(mResourcesValidResult);
	if (mResourcesValidContext->osStatus() != errSecSuccess)
		mResourcesValidContext->throwMe();
}


void SecStaticCode::checkOptionalResource(CFTypeRef key, CFTypeRef value, void *context)
{
	ValidationContext *ctx = static_cast<ValidationContext *>(context);
	ResourceSeal seal(value);
	if (!seal.optional()) {
		if (key && CFGetTypeID(key) == CFStringGetTypeID()) {
			CFTempURL tempURL(CFStringRef(key), false, ctx->code.resourceBase());
			if (!tempURL.get()) {
				ctx->reportProblem(errSecCSBadDictionaryFormat, kSecCFErrorResourceSeal, key);
			} else {
				ctx->reportProblem(errSecCSBadResource, kSecCFErrorResourceMissing, tempURL);
			}
		} else {
			ctx->reportProblem(errSecCSBadResource, kSecCFErrorResourceSeal, key);
		}
	}
}


static bool isOmitRule(CFTypeRef value)
{
	if (CFGetTypeID(value) == CFBooleanGetTypeID())
		return value == kCFBooleanFalse;
	CFDictionary rule(value, errSecCSResourceRulesInvalid);
	return rule.get<CFBooleanRef>("omit") == kCFBooleanTrue;
}

bool SecStaticCode::hasWeakResourceRules(CFDictionaryRef rulesDict, uint32_t version, CFArrayRef allowedOmissions)
{
	// compute allowed omissions
	CFRef<CFArrayRef> defaultOmissions = this->diskRep()->allowedResourceOmissions();
	if (!defaultOmissions)
		MacOSError::throwMe(errSecCSInternalError);
	CFRef<CFMutableArrayRef> allowed = CFArrayCreateMutableCopy(NULL, 0, defaultOmissions);
	if (allowedOmissions)
		CFArrayAppendArray(allowed, allowedOmissions, CFRangeMake(0, CFArrayGetCount(allowedOmissions)));
	CFRange range = CFRangeMake(0, CFArrayGetCount(allowed));
	
	// check all resource rules for weakness
	string catchAllRule = (version == 1) ? "^Resources/" : "^.*";
	__block bool coversAll = false;
	__block bool forbiddenOmission = false;
	CFArrayRef allowedRef = allowed.get();	// (into block)
	CFDictionary rules(rulesDict, errSecCSResourceRulesInvalid);
	rules.apply(^(CFStringRef key, CFTypeRef value) {
		string pattern = cfString(key, errSecCSResourceRulesInvalid);
		if (pattern == catchAllRule && value == kCFBooleanTrue) {
			coversAll = true;
			return;
		}
		if (isOmitRule(value))
			forbiddenOmission |= !CFArrayContainsValue(allowedRef, range, key);
	});

	return !coversAll || forbiddenOmission;
}


//
// Load, validate, cache, and return CFDictionary forms of sealed resources.
//
CFDictionaryRef SecStaticCode::infoDictionary()
{
	if (!mInfoDict) {
		mInfoDict.take(getDictionary(cdInfoSlot, errSecCSInfoPlistFailed));
		secdebug("staticCode", "%p loaded InfoDict %p", this, mInfoDict.get());
	}
	return mInfoDict;
}

CFDictionaryRef SecStaticCode::entitlements()
{
	if (!mEntitlements) {
		validateDirectory();
		if (CFDataRef entitlementData = component(cdEntitlementSlot)) {
			validateComponent(cdEntitlementSlot);
			const EntitlementBlob *blob = reinterpret_cast<const EntitlementBlob *>(CFDataGetBytePtr(entitlementData));
			if (blob->validateBlob()) {
				mEntitlements.take(blob->entitlements());
				secdebug("staticCode", "%p loaded Entitlements %p", this, mEntitlements.get());
			}
			// we do not consider a different blob type to be an error. We think it's a new format we don't understand
		}
	}
	return mEntitlements;
}

CFDictionaryRef SecStaticCode::resourceDictionary(bool check /* = true */)
{
	if (mResourceDict)	// cached
		return mResourceDict;
	if (CFRef<CFDictionaryRef> dict = getDictionary(cdResourceDirSlot, check))
		if (cfscan(dict, "{rules=%Dn,files=%Dn}")) {
			secdebug("staticCode", "%p loaded ResourceDict %p",
				this, mResourceDict.get());
			return mResourceDict = dict;
		}
	// bad format
	return NULL;
}


//
// Load and cache the resource directory base.
// Note that the base is optional for each DiskRep.
//
CFURLRef SecStaticCode::resourceBase()
{
	if (!mGotResourceBase) {
		string base = mRep->resourcesRootPath();
		if (!base.empty())
			mResourceBase.take(makeCFURL(base, true));
		mGotResourceBase = true;
	}
	return mResourceBase;
}


//
// Load a component, validate it, convert it to a CFDictionary, and return that.
// This will force load and validation, which means that it will perform basic
// validation if it hasn't been done yet.
//
CFDictionaryRef SecStaticCode::getDictionary(CodeDirectory::SpecialSlot slot, bool check /* = true */)
{
	if (check)
		validateDirectory();
	if (CFDataRef infoData = component(slot)) {
		validateComponent(slot);
		if (CFDictionaryRef dict = makeCFDictionaryFrom(infoData))
			return dict;
		else
			MacOSError::throwMe(errSecCSBadDictionaryFormat);
	}
	return NULL;
}


//
// Load, validate, and return a sealed resource.
// The resource data (loaded in to memory as a blob) is returned and becomes
// the responsibility of the caller; it is NOT cached by SecStaticCode.
//
// A resource that is not sealed will not be returned, and an error will be thrown.
// A missing resource will cause an error unless it's marked optional in the Directory.
// Under no circumstances will a corrupt resource be returned.
// NULL will only be returned for a resource that is neither sealed nor present
// (or that is sealed, absent, and marked optional).
// If the ResourceDictionary itself is not sealed, this function will always fail.
//
// There is currently no interface for partial retrieval of the resource data.
// (Since the ResourceDirectory does not currently support segmentation, all the
// data would have to be read anyway, but it could be read into a reusable buffer.)
//
CFDataRef SecStaticCode::resource(string path, ValidationContext &ctx)
{
	if (CFDictionaryRef rdict = resourceDictionary()) {
		if (CFTypeRef file = cfget(rdict, "files.%s", path.c_str())) {
			ResourceSeal seal = file;
			if (!resourceBase())	// no resources in DiskRep
				MacOSError::throwMe(errSecCSResourcesNotFound);
			if (seal.nested())
				MacOSError::throwMe(errSecCSResourcesNotSealed);	// (it's nested code)
			CFRef<CFURLRef> fullpath = makeCFURL(path, false, resourceBase());
			if (CFRef<CFDataRef> data = cfLoadFile(fullpath)) {
				MakeHash<CodeDirectory> hasher(this->codeDirectory());
				hasher->update(CFDataGetBytePtr(data), CFDataGetLength(data));
				if (hasher->verify(seal.hash()))
					return data.yield();	// good
				else
					ctx.reportProblem(errSecCSBadResource, kSecCFErrorResourceAltered, fullpath); // altered
			} else {
				if (!seal.optional())
					ctx.reportProblem(errSecCSBadResource, kSecCFErrorResourceMissing, fullpath); // was sealed but is now missing
				else
					return NULL;	// validly missing
			}
		} else
			ctx.reportProblem(errSecCSBadResource, kSecCFErrorResourceAdded, CFTempURL(path, false, resourceBase()));
		return NULL;
	} else
		MacOSError::throwMe(errSecCSResourcesNotSealed);
}

CFDataRef SecStaticCode::resource(string path)
{
	ValidationContext ctx(*this);
	return resource(path, ctx);
}

void SecStaticCode::validateResource(CFDictionaryRef files, string path, bool isSymlink, ValidationContext &ctx, SecCSFlags flags, uint32_t version)
{
	if (!resourceBase())	// no resources in DiskRep
		MacOSError::throwMe(errSecCSResourcesNotFound);
	CFRef<CFURLRef> fullpath = makeCFURL(path, false, resourceBase());
	if (CFTypeRef file = CFDictionaryGetValue(files, CFTempString(path))) {
		ResourceSeal seal = file;
		if (seal.nested()) {
			if (isSymlink)
				return ctx.reportProblem(errSecCSBadResource, kSecCFErrorResourceAltered, fullpath); // changed type
			string suffix = ".framework";
			bool isFramework = (path.length() > suffix.length())
				&& (path.compare(path.length()-suffix.length(), suffix.length(), suffix) == 0);
			validateNestedCode(fullpath, seal, flags, isFramework);
		} else if (seal.link()) {
			char target[PATH_MAX];
			ssize_t len = ::readlink(cfString(fullpath).c_str(), target, sizeof(target)-1);
			if (len < 0)
				UnixError::check(-1);
			target[len] = '\0';
			if (cfString(seal.link()) != target)
				ctx.reportProblem(errSecCSBadResource, kSecCFErrorResourceAltered, fullpath);
		} else if (seal.hash()) {	// genuine file
			if (isSymlink)
				return ctx.reportProblem(errSecCSBadResource, kSecCFErrorResourceAltered, fullpath); // changed type
			AutoFileDesc fd(cfString(fullpath), O_RDONLY, FileDesc::modeMissingOk);	// open optional file
			if (fd) {
				MakeHash<CodeDirectory> hasher(this->codeDirectory());
				hashFileData(fd, hasher.get());
				if (hasher->verify(seal.hash()))
					return;			// verify good
				else
					ctx.reportProblem(errSecCSBadResource, kSecCFErrorResourceAltered, fullpath); // altered
			} else {
				if (!seal.optional())
					ctx.reportProblem(errSecCSBadResource, kSecCFErrorResourceMissing, fullpath); // was sealed but is now missing
				else
					return;			// validly missing
			}
		} else
			ctx.reportProblem(errSecCSBadResource, kSecCFErrorResourceAltered, fullpath); // changed type
		return;
	}
	if (version == 1) {		// version 1 ignores symlinks altogether
		char target[PATH_MAX];
		if (::readlink(cfString(fullpath).c_str(), target, sizeof(target)) > 0)
			return;
	}
	ctx.reportProblem(errSecCSBadResource, kSecCFErrorResourceAdded, CFTempURL(path, false, resourceBase()));
}

void SecStaticCode::validateNestedCode(CFURLRef path, const ResourceSeal &seal, SecCSFlags flags, bool isFramework)
{
	CFRef<SecRequirementRef> req;
	if (SecRequirementCreateWithString(seal.requirement(), kSecCSDefaultFlags, &req.aref()))
		MacOSError::throwMe(errSecCSResourcesInvalid);
	
	// recursively verify this nested code
	try {
		if (!(flags & kSecCSCheckNestedCode))
			flags |= kSecCSBasicValidateOnly;
		SecPointer<SecStaticCode> code = new SecStaticCode(DiskRep::bestGuess(cfString(path)));
		code->initializeFromParent(*this);
		code->staticValidate(flags, SecRequirement::required(req));

		if (isFramework && (flags & kSecCSStrictValidate))
			try {
				validateOtherVersions(path, flags, req, code);
			} catch (const CSError &err) {
				MacOSError::throwMe(errSecCSBadFrameworkVersion);
			} catch (const MacOSError &err) {
				MacOSError::throwMe(errSecCSBadFrameworkVersion);
			}

	} catch (CSError &err) {
		if (err.error == errSecCSReqFailed) {
			mResourcesValidContext->reportProblem(errSecCSBadNestedCode, kSecCFErrorResourceAltered, path);
			return;
		}
		err.augment(kSecCFErrorPath, path);
		throw;
	} catch (const MacOSError &err) {
		if (err.error == errSecCSReqFailed) {
			mResourcesValidContext->reportProblem(errSecCSBadNestedCode, kSecCFErrorResourceAltered, path);
			return;
		}
		CSError::throwMe(err.error, kSecCFErrorPath, path);
	}
}

void SecStaticCode::validateOtherVersions(CFURLRef path, SecCSFlags flags, SecRequirementRef req, SecStaticCode *code)
{
	// Find out what current points to and do not revalidate
	std::string mainPath = cfStringRelease(code->diskRep()->copyCanonicalPath());

	char main_path[PATH_MAX];
	bool foundTarget = false;

	/* If it failed to get the target of the symlink, do not fail. It is a performance loss,
	 not a security hole */
	if (realpath(mainPath.c_str(), main_path) != NULL)
		foundTarget = true;

	std::ostringstream versionsPath;
	versionsPath << cfString(path) << "/Versions/";

	DirScanner scanner(versionsPath.str());

	if (scanner.initialized()) {
		struct dirent *entry = NULL;
		while ((entry = scanner.getNext()) != NULL) {
			std::ostringstream fullPath;

			if (entry->d_type != DT_DIR ||
				strcmp(entry->d_name, ".") == 0 ||
				strcmp(entry->d_name, "..") == 0 ||
				strcmp(entry->d_name, "Current") == 0)
				continue;

			fullPath << versionsPath.str() << entry->d_name;

			char real_full_path[PATH_MAX];
			if (realpath(fullPath.str().c_str(), real_full_path) == NULL)
				UnixError::check(-1);

			// Do case insensitive comparions because realpath() was called for both paths
			if (foundTarget && strcmp(main_path, real_full_path) == 0)
				continue;

			SecPointer<SecStaticCode> frameworkVersion = new SecStaticCode(DiskRep::bestGuess(real_full_path));
			frameworkVersion->initializeFromParent(*this);
			frameworkVersion->staticValidate(flags, SecRequirement::required(req));
		}
	}
}


//
// Test a CodeDirectory flag.
// Returns false if there is no CodeDirectory.
// May throw if the CodeDirectory is present but somehow invalid.
//
bool SecStaticCode::flag(uint32_t tested)
{
	if (const CodeDirectory *cd = this->codeDirectory(false))
		return cd->flags & tested;
	else
		return false;
}


//
// Retrieve the full SuperBlob containing all internal requirements.
//
const Requirements *SecStaticCode::internalRequirements()
{
	if (CFDataRef reqData = component(cdRequirementsSlot)) {
		const Requirements *req = (const Requirements *)CFDataGetBytePtr(reqData);
		if (!req->validateBlob())
			MacOSError::throwMe(errSecCSReqInvalid);
		return req;
	} else
		return NULL;
}


//
// Retrieve a particular internal requirement by type.
//
const Requirement *SecStaticCode::internalRequirement(SecRequirementType type)
{
	if (const Requirements *reqs = internalRequirements())
		return reqs->find<Requirement>(type);
	else
		return NULL;
}


//
// Return the Designated Requirement (DR). This can be either explicit in the
// Internal Requirements component, or implicitly generated on demand here.
// Note that an explicit DR may have been implicitly generated at signing time;
// we don't distinguish this case.
//
const Requirement *SecStaticCode::designatedRequirement()
{
	if (const Requirement *req = internalRequirement(kSecDesignatedRequirementType)) {
		return req;		// explicit in signing data
	} else {
		if (!mDesignatedReq)
			mDesignatedReq = defaultDesignatedRequirement();
		return mDesignatedReq;
	}
}


//
// Generate the default Designated Requirement (DR) for this StaticCode.
// Ignore any explicit DR it may contain.
//
const Requirement *SecStaticCode::defaultDesignatedRequirement()
{
	if (flag(kSecCodeSignatureAdhoc)) {
		// adhoc signature: return a cdhash requirement for all architectures
		__block Requirement::Maker maker;
		Requirement::Maker::Chain chain(maker, opOr);
		
		// insert cdhash requirement for all architectures
		chain.add();
		maker.cdhash(this->cdHash());
		handleOtherArchitectures(^(SecStaticCode *subcode) {
			if (CFDataRef cdhash = subcode->cdHash()) {
				chain.add();
				maker.cdhash(cdhash);
			}
		});
		return maker.make();
	} else {
		// full signature: Gin up full context and let DRMaker do its thing
		validateDirectory();		// need the cert chain
		Requirement::Context context(this->certificates(),
			this->infoDictionary(),
			this->entitlements(),
			this->identifier(),
			this->codeDirectory()
		);
		return DRMaker(context).make();
	}
}


//
// Validate a SecStaticCode against the internal requirement of a particular type.
//
void SecStaticCode::validateRequirements(SecRequirementType type, SecStaticCode *target,
	OSStatus nullError /* = errSecSuccess */)
{
	DTRACK(CODESIGN_EVAL_STATIC_INTREQ, this, type, target, nullError);
	if (const Requirement *req = internalRequirement(type))
		target->validateRequirement(req, nullError ? nullError : errSecCSReqFailed);
	else if (nullError)
		MacOSError::throwMe(nullError);
	else
		/* accept it */;
}


//
// Validate this StaticCode against an external Requirement
//
bool SecStaticCode::satisfiesRequirement(const Requirement *req, OSStatus failure)
{
	assert(req);
	validateDirectory();
	return req->validates(Requirement::Context(mCertChain, infoDictionary(), entitlements(), codeDirectory()->identifier(), codeDirectory()), failure);
}

void SecStaticCode::validateRequirement(const Requirement *req, OSStatus failure)
{
	if (!this->satisfiesRequirement(req, failure))
		MacOSError::throwMe(failure);
}


//
// Retrieve one certificate from the cert chain.
// Positive and negative indices can be used:
//    [ leaf, intermed-1, ..., intermed-n, anchor ]
//        0       1       ...     -2         -1
// Returns NULL if unavailable for any reason.
//
SecCertificateRef SecStaticCode::cert(int ix)
{
	validateDirectory();		// need cert chain
	if (mCertChain) {
		CFIndex length = CFArrayGetCount(mCertChain);
		if (ix < 0)
			ix += length;
		if (ix >= 0 && ix < length)
			return SecCertificateRef(CFArrayGetValueAtIndex(mCertChain, ix));
	}
	return NULL;
}

CFArrayRef SecStaticCode::certificates()
{
	validateDirectory();		// need cert chain
	return mCertChain;
}


//
// Gather (mostly) API-official information about this StaticCode.
//
// This method lives in the twilight between the API and internal layers,
// since it generates API objects (Sec*Refs) for return.
//
CFDictionaryRef SecStaticCode::signingInformation(SecCSFlags flags)
{
	//
	// Start with the pieces that we return even for unsigned code.
	// This makes Sec[Static]CodeRefs useful as API-level replacements
	// of our internal OSXCode objects.
	//
	CFRef<CFMutableDictionaryRef> dict = makeCFMutableDictionary(1,
		kSecCodeInfoMainExecutable, CFTempURL(this->mainExecutablePath()).get()
	);
	
	//
	// If we're not signed, this is all you get
	//
	if (!this->isSigned())
		return dict.yield();
	
	//
	// Add the generic attributes that we always include
	//
	CFDictionaryAddValue(dict, kSecCodeInfoIdentifier, CFTempString(this->identifier()));
	CFDictionaryAddValue(dict, kSecCodeInfoFlags, CFTempNumber(this->codeDirectory(false)->flags.get()));
	CFDictionaryAddValue(dict, kSecCodeInfoFormat, CFTempString(this->format()));
	CFDictionaryAddValue(dict, kSecCodeInfoSource, CFTempString(this->signatureSource()));
	CFDictionaryAddValue(dict, kSecCodeInfoUnique, this->cdHash());
	CFDictionaryAddValue(dict, kSecCodeInfoDigestAlgorithm, CFTempNumber(this->codeDirectory(false)->hashType));

	//
	// Deliver any Info.plist only if it looks intact
	//
	try {
		if (CFDictionaryRef info = this->infoDictionary())
			CFDictionaryAddValue(dict, kSecCodeInfoPList, info);
	} catch (...) { }		// don't deliver Info.plist if questionable

	//
	// kSecCSSigningInformation adds information about signing certificates and chains
	//
	if (flags & kSecCSSigningInformation)
		try {
			if (CFArrayRef certs = this->certificates())
				CFDictionaryAddValue(dict, kSecCodeInfoCertificates, certs);
			if (CFDataRef sig = this->signature())
				CFDictionaryAddValue(dict, kSecCodeInfoCMS, sig);
			if (mTrust)
				CFDictionaryAddValue(dict, kSecCodeInfoTrust, mTrust);
			if (CFAbsoluteTime time = this->signingTime())
				if (CFRef<CFDateRef> date = CFDateCreate(NULL, time))
					CFDictionaryAddValue(dict, kSecCodeInfoTime, date);
			if (CFAbsoluteTime time = this->signingTimestamp())
				if (CFRef<CFDateRef> date = CFDateCreate(NULL, time))
					CFDictionaryAddValue(dict, kSecCodeInfoTimestamp, date);
			if (const char *teamID = this->teamID())
				CFDictionaryAddValue(dict, kSecCodeInfoTeamIdentifier, CFTempString(teamID));
		} catch (...) { }
	
	//
	// kSecCSRequirementInformation adds information on requirements
	//
	if (flags & kSecCSRequirementInformation)
		try {
			if (const Requirements *reqs = this->internalRequirements()) {
				CFDictionaryAddValue(dict, kSecCodeInfoRequirements,
					CFTempString(Dumper::dump(reqs)));
				CFDictionaryAddValue(dict, kSecCodeInfoRequirementData, CFTempData(*reqs));
			}
			
			const Requirement *dreq = this->designatedRequirement();
			CFRef<SecRequirementRef> dreqRef = (new SecRequirement(dreq))->handle();
			CFDictionaryAddValue(dict, kSecCodeInfoDesignatedRequirement, dreqRef);
			if (this->internalRequirement(kSecDesignatedRequirementType)) {	// explicit
				CFRef<SecRequirementRef> ddreqRef = (new SecRequirement(this->defaultDesignatedRequirement(), true))->handle();
				CFDictionaryAddValue(dict, kSecCodeInfoImplicitDesignatedRequirement, ddreqRef);
			} else {	// implicit
				CFDictionaryAddValue(dict, kSecCodeInfoImplicitDesignatedRequirement, dreqRef);
			}
		} catch (...) { }
		
		try {
		   if (CFDataRef ent = this->component(cdEntitlementSlot)) {
			   CFDictionaryAddValue(dict, kSecCodeInfoEntitlements, ent);
			   if (CFDictionaryRef entdict = this->entitlements())
					CFDictionaryAddValue(dict, kSecCodeInfoEntitlementsDict, entdict);
			}
		} catch (...) { }
	
	//
	// kSecCSInternalInformation adds internal information meant to be for Apple internal
	// use (SPI), and not guaranteed to be stable. Primarily, this is data we want
	// to reliably transmit through the API wall so that code outside the Security.framework
	// can use it without having to play nasty tricks to get it.
	//
	if (flags & kSecCSInternalInformation)
		try {
			if (mDir)
				CFDictionaryAddValue(dict, kSecCodeInfoCodeDirectory, mDir);
			CFDictionaryAddValue(dict, kSecCodeInfoCodeOffset, CFTempNumber(mRep->signingBase()));
		if (CFRef<CFDictionaryRef> rdict = getDictionary(cdResourceDirSlot, false))	// suppress validation
			CFDictionaryAddValue(dict, kSecCodeInfoResourceDirectory, rdict);
		} catch (...) { }
	
	
	//
	// kSecCSContentInformation adds more information about the physical layout
	// of the signed code. This is (only) useful for packaging or patching-oriented
	// applications.
	//
	if (flags & kSecCSContentInformation)
		if (CFRef<CFArrayRef> files = mRep->modifiedFiles())
			CFDictionaryAddValue(dict, kSecCodeInfoChangedFiles, files);
	
	return dict.yield();
}


//
// Resource validation contexts.
// The default context simply throws a CSError, rudely terminating the operation.
//
SecStaticCode::ValidationContext::~ValidationContext()
{ /* virtual */ }

void SecStaticCode::ValidationContext::reportProblem(OSStatus rc, CFStringRef type, CFTypeRef value)
{
	CSError::throwMe(rc, type, value);
}

void SecStaticCode::CollectingContext::reportProblem(OSStatus rc, CFStringRef type, CFTypeRef value)
{
	StLock<Mutex> _(mLock);
	if (mStatus == errSecSuccess)
		mStatus = rc;			// record first failure for eventual error return
	if (type) {
		if (!mCollection)
			mCollection.take(makeCFMutableDictionary());
		CFMutableArrayRef element = CFMutableArrayRef(CFDictionaryGetValue(mCollection, type));
		if (!element) {
			element = makeCFMutableArray(0);
			if (!element)
				CFError::throwMe();
			CFDictionaryAddValue(mCollection, type, element);
			CFRelease(element);
		}
		CFArrayAppendValue(element, value);
	}
}

void SecStaticCode::CollectingContext::throwMe()
{
	assert(mStatus != errSecSuccess);
	throw CSError(mStatus, mCollection.retain());
}


//
// Master validation driver.
// This is the static validation (only) driver for the API.
//
// SecStaticCode exposes an a la carte menu of topical validators applying
// to a given object. The static validation API pulls them together reliably,
// but it also adds two matrix dimensions: architecture (for "fat" Mach-O binaries)
// and nested code. This function will crawl a suitable cross-section of this
// validation matrix based on which options it is given, creating temporary
// SecStaticCode objects on the fly to complete the task.
// (The point, of course, is to do as little duplicate work as possible.)
//
void SecStaticCode::staticValidate(SecCSFlags flags, const SecRequirement *req)
{
	setValidationFlags(flags);
	
	// initialize progress/cancellation state
	if (flags & kSecCSReportProgress)
	prepareProgress(estimateResourceWorkload() + 2);	// +1 head, +1 tail

	// core components: once per architecture (if any)
	this->staticValidateCore(flags, req);
	if (flags & kSecCSCheckAllArchitectures)
		handleOtherArchitectures(^(SecStaticCode* subcode) {
			if (flags & kSecCSCheckGatekeeperArchitectures) {
				Universal *fat = subcode->diskRep()->mainExecutableImage();
				assert(fat && fat->narrowed());	// handleOtherArchitectures gave us a focused architecture slice
				Architecture arch = fat->bestNativeArch();	// actually, the ONLY one
				if ((arch.cpuType() & ~CPU_ARCH_MASK) == CPU_TYPE_POWERPC)
					return;	// irrelevant to Gatekeeper
			}
			subcode->detachedSignature(this->mDetachedSig);	// carry over explicit (but not implicit) architecture
			subcode->staticValidateCore(flags, req);
		});
	reportProgress();
	
	// allow monitor intervention in source validation phase
	reportEvent(CFSTR("prepared"), NULL);
	
	// resources: once for all architectures
	if (!(flags & kSecCSDoNotValidateResources))
		this->validateResources(flags);

	// perform strict validation if desired
	if (flags & kSecCSStrictValidate)
		mRep->strictValidate(codeDirectory(), mTolerateErrors);
	reportProgress();

	// allow monitor intervention
	if (CFRef<CFTypeRef> veto = reportEvent(CFSTR("validated"), NULL)) {
		if (CFGetTypeID(veto) == CFNumberGetTypeID())
			MacOSError::throwMe(cfNumber<OSStatus>(veto.as<CFNumberRef>()));
		else
			MacOSError::throwMe(errSecCSBadCallbackValue);
	}
}

void SecStaticCode::staticValidateCore(SecCSFlags flags, const SecRequirement *req)
{
	try {
		this->validateNonResourceComponents();	// also validates the CodeDirectory
		if (!(flags & kSecCSDoNotValidateExecutable))
			this->validateExecutable();
		if (req)
			this->validateRequirement(req->requirement(), errSecCSReqFailed);
    } catch (CSError &err) {
        if (Universal *fat = this->diskRep()->mainExecutableImage())    // Mach-O
            if (MachO *mach = fat->architecture()) {
                err.augment(kSecCFErrorArchitecture, CFTempString(mach->architecture().displayName()));
                delete mach;
            }
        throw;
    } catch (const MacOSError &err) {
        // add architecture information if we can get it
        if (Universal *fat = this->diskRep()->mainExecutableImage())
            if (MachO *mach = fat->architecture()) {
                CFTempString arch(mach->architecture().displayName());
                delete mach;
                CSError::throwMe(err.error, kSecCFErrorArchitecture, arch);
            }
        throw;
    }
}


//
// A helper that generates SecStaticCode objects for all but the primary architecture
// of a fat binary and calls a block on them.
// If there's only one architecture (or this is an architecture-agnostic code),
// nothing happens quickly.
//
void SecStaticCode::handleOtherArchitectures(void (^handle)(SecStaticCode* other))
{
	if (Universal *fat = this->diskRep()->mainExecutableImage()) {
		Universal::Architectures architectures;
		fat->architectures(architectures);
		if (architectures.size() > 1) {
			DiskRep::Context ctx;
			size_t activeOffset = fat->archOffset();
			for (Universal::Architectures::const_iterator arch = architectures.begin(); arch != architectures.end(); ++arch) {
				ctx.offset = fat->archOffset(*arch);
				if (ctx.offset > SIZE_MAX)
					MacOSError::throwMe(errSecCSInternalError);
				ctx.size = fat->lengthOfSlice((size_t)ctx.offset);
				if (ctx.offset != activeOffset) {	// inactive architecture; check it
					SecPointer<SecStaticCode> subcode = new SecStaticCode(DiskRep::bestGuess(this->mainExecutablePath(), &ctx));
					subcode->detachedSignature(this->mDetachedSig); // carry over explicit (but not implicit) detached signature
					if (this->teamID() == NULL || subcode->teamID() == NULL) {
						if (this->teamID() != subcode->teamID())
							MacOSError::throwMe(errSecCSSignatureInvalid);
					} else if (strcmp(this->teamID(), subcode->teamID()) != 0)
						MacOSError::throwMe(errSecCSSignatureInvalid);
					handle(subcode);
				}
			}
		}
	}
}

//
// A method that takes a certificate chain (certs) and evaluates
// if it is a Mac or IPhone developer cert, an app store distribution cert,
// or a developer ID
//
bool SecStaticCode::isAppleDeveloperCert(CFArrayRef certs)
{
	static const std::string appleDeveloperRequirement = "(" + std::string(WWDRRequirement) + ") or (" + MACWWDRRequirement + ") or (" + developerID + ") or (" + distributionCertificate + ") or (" + iPhoneDistributionCert + ")";
	SecPointer<SecRequirement> req = new SecRequirement(parseRequirement(appleDeveloperRequirement), true);
	Requirement::Context ctx(certs, NULL, NULL, "", NULL);

	return req->requirement()->validates(ctx);
}

} // end namespace CodeSigning
} // end namespace Security