/*

* Copyright (C) 2013-2019 Apple Inc. All rights reserved.

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#include "config.h"

#include "CryptoKeyRSA.h"

#if ENABLE(WEB_CRYPTO)

#include "CommonCryptoDERUtilities.h"

#include "CommonCryptoUtilities.h"

#include "CryptoAlgorithmRegistry.h"

#include "CryptoKeyPair.h"

#include "CryptoKeyRSAComponents.h"

#include "ScriptExecutionContext.h"

#include <JavaScriptCore/GenericTypedArrayViewInlines.h>

#include <JavaScriptCore/HeapInlines.h>

#include <JavaScriptCore/JSGenericTypedArrayViewInlines.h>

#include <wtf/MainThread.h>

namespace WebCore {

// OID rsaEncryption: 1.2.840.113549.1.1.1. Per https://tools.ietf.org/html/rfc3279#section-2.3.1

static const unsigned char RSAOIDHeader[] = {0x30, 0x0d, 0x06, 0x09, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01, 0x01, 0x01, 0x05, 0x00};

// FIXME: We should get rid of magic number 16384. It assumes that the length of provided key will not exceed 16KB.

// https://bugs.webkit.org/show_bug.cgi?id=164942

static CCCryptorStatus getPublicKeyComponents(const PlatformRSAKeyContainer& rsaKey, Vector<uint8_t>& modulus, Vector<uint8_t>& publicExponent)

{

ASSERT(CCRSAGetKeyType(rsaKey.get()) == ccRSAKeyPublic || CCRSAGetKeyType(rsaKey.get()) == ccRSAKeyPrivate);

bool keyIsPublic = CCRSAGetKeyType(rsaKey.get()) == ccRSAKeyPublic;

ALLOW_DEPRECATED_DECLARATIONS_BEGIN

PlatformRSAKeyContainer publicKeyFromPrivateKey(keyIsPublic ? nullptr : CCRSACryptorGetPublicKeyFromPrivateKey(rsaKey.get()));

ALLOW_DEPRECATED_DECLARATIONS_END

modulus.resize(16384);

size_t modulusLength = modulus.size();

publicExponent.resize(16384);

size_t exponentLength = publicExponent.size();

CCCryptorStatus status = CCRSAGetKeyComponents(keyIsPublic ? rsaKey.get() : publicKeyFromPrivateKey.get(), modulus.data(), &modulusLength, publicExponent.data(), &exponentLength, 0, 0, 0, 0);

if (status)

return status;

modulus.shrink(modulusLength);

publicExponent.shrink(exponentLength);

return status;

}

static CCCryptorStatus getPrivateKeyComponents(const PlatformRSAKeyContainer& rsaKey, Vector<uint8_t>& privateExponent, CryptoKeyRSAComponents::PrimeInfo& firstPrimeInfo, CryptoKeyRSAComponents::PrimeInfo& secondPrimeInfo)

{

ASSERT(CCRSAGetKeyType(rsaKey.get()) == ccRSAKeyPrivate);

Vector<uint8_t> unusedModulus(16384);

size_t modulusLength = unusedModulus.size();

privateExponent.resize(16384);

size_t exponentLength = privateExponent.size();

firstPrimeInfo.primeFactor.resize(16384);

size_t pLength = firstPrimeInfo.primeFactor.size();

secondPrimeInfo.primeFactor.resize(16384);

size_t qLength = secondPrimeInfo.primeFactor.size();

CCCryptorStatus status = CCRSAGetKeyComponents(rsaKey.get(), unusedModulus.data(), &modulusLength, privateExponent.data(), &exponentLength, firstPrimeInfo.primeFactor.data(), &pLength, secondPrimeInfo.primeFactor.data(), &qLength);

if (status)

return status;

privateExponent.shrink(exponentLength);

firstPrimeInfo.primeFactor.shrink(pLength);

secondPrimeInfo.primeFactor.shrink(qLength);

size_t dpSize;

size_t dqSize;

size_t qinvSize;

if (auto status = CCRSAGetCRTComponentsSizes(rsaKey.get(), &dpSize, &dqSize, &qinvSize))

return status;

Vector<uint8_t> dp(dpSize);

Vector<uint8_t> dq(dqSize);

Vector<uint8_t> qinv(qinvSize);

if (auto status = CCRSAGetCRTComponents(rsaKey.get(), dp.data(), dpSize, dq.data(), dqSize, qinv.data(), qinvSize))

return status;

firstPrimeInfo.factorCRTExponent = WTFMove(dp);

secondPrimeInfo.factorCRTExponent = WTFMove(dq);

secondPrimeInfo.factorCRTCoefficient = WTFMove(qinv);

return status;

}

CryptoKeyRSA::CryptoKeyRSA(CryptoAlgorithmIdentifier identifier, CryptoAlgorithmIdentifier hash, bool hasHash, CryptoKeyType type, PlatformRSAKeyContainer&& platformKey, bool extractable, CryptoKeyUsageBitmap usage)

: CryptoKey(identifier, type, extractable, usage)

, m_platformKey(WTFMove(platformKey))

, m_restrictedToSpecificHash(hasHash)

, m_hash(hash)

{

}

RefPtr<CryptoKeyRSA> CryptoKeyRSA::create(CryptoAlgorithmIdentifier identifier, CryptoAlgorithmIdentifier hash, bool hasHash, const CryptoKeyRSAComponents& keyData, bool extractable, CryptoKeyUsageBitmap usage)

{

if (keyData.type() == CryptoKeyRSAComponents::Type::Private && !keyData.hasAdditionalPrivateKeyParameters()) {

// <rdar://problem/15452324> tracks adding support.

WTFLogAlways("Private keys without additional data are not supported");

return nullptr;

}

if (keyData.otherPrimeInfos().size()) {

// <rdar://problem/15444074> tracks adding support.

WTFLogAlways("Keys with more than two primes are not supported");

return nullptr;

}

// When an empty vector p is provided to CCRSACryptorCreateFromData to create a private key, it crashes.

// <rdar://problem/30550228> tracks the issue.

if (keyData.type() == CryptoKeyRSAComponents::Type::Private && keyData.firstPrimeInfo().primeFactor.isEmpty())

return nullptr;

CCRSACryptorRef cryptor = nullptr;

// FIXME: It is so weired that we recaculate the private exponent from first prime factor and second prime factor,

// given the fact that we have already had it. Also, the re-caculated private exponent may not match the given one.

// See <rdar://problem/15452324>.

CCCryptorStatus status = CCRSACryptorCreateFromData(

keyData.type() == CryptoKeyRSAComponents::Type::Public ? ccRSAKeyPublic : ccRSAKeyPrivate,

keyData.modulus().data(), keyData.modulus().size(),

keyData.exponent().data(), keyData.exponent().size(),

keyData.firstPrimeInfo().primeFactor.data(), keyData.firstPrimeInfo().primeFactor.size(),

keyData.secondPrimeInfo().primeFactor.data(), keyData.secondPrimeInfo().primeFactor.size(),

&cryptor);

if (status) {

LOG_ERROR("Couldn't create RSA key from data, error %d", status);

return nullptr;

}

return adoptRef(new CryptoKeyRSA(identifier, hash, hasHash, keyData.type() == CryptoKeyRSAComponents::Type::Public ? CryptoKeyType::Public : CryptoKeyType::Private, PlatformRSAKeyContainer(cryptor), extractable, usage));

}

bool CryptoKeyRSA::isRestrictedToHash(CryptoAlgorithmIdentifier& identifier) const

{

if (!m_restrictedToSpecificHash)

return false;

identifier = m_hash;

return true;

}

size_t CryptoKeyRSA::keySizeInBits() const

{

Vector<uint8_t> modulus;

Vector<uint8_t> publicExponent;

CCCryptorStatus status = getPublicKeyComponents(m_platformKey, modulus, publicExponent);

if (status) {

WTFLogAlways("Couldn't get RSA key components, status %d", status);

return 0;

}

return modulus.size() * 8;

}

auto CryptoKeyRSA::algorithm() const -> KeyAlgorithm

{

// FIXME: Add a version of getPublicKeyComponents that returns Uint8Array, rather

// than Vector<uint8_t>, to avoid a copy of the data.

Vector<uint8_t> modulus;

Vector<uint8_t> publicExponent;

CCCryptorStatus status = getPublicKeyComponents(m_platformKey, modulus, publicExponent);

if (status) {

WTFLogAlways("Couldn't get RSA key components, status %d", status);

publicExponent.clear();

CryptoRsaKeyAlgorithm result;

result.name = CryptoAlgorithmRegistry::singleton().name(algorithmIdentifier());

result.modulusLength = 0;

result.publicExponent = Uint8Array::tryCreate(0);

return result;

}

size_t modulusLength = modulus.size() * 8;

if (m_restrictedToSpecificHash) {

CryptoRsaHashedKeyAlgorithm result;

result.name = CryptoAlgorithmRegistry::singleton().name(algorithmIdentifier());

result.modulusLength = modulusLength;

result.publicExponent = Uint8Array::tryCreate(publicExponent.data(), publicExponent.size());

result.hash.name = CryptoAlgorithmRegistry::singleton().name(m_hash);

return result;

}

CryptoRsaKeyAlgorithm result;

result.name = CryptoAlgorithmRegistry::singleton().name(algorithmIdentifier());

result.modulusLength = modulusLength;

result.publicExponent = Uint8Array::tryCreate(publicExponent.data(), publicExponent.size());

return result;

}

std::unique_ptr<CryptoKeyRSAComponents> CryptoKeyRSA::exportData() const

{

switch (CCRSAGetKeyType(m_platformKey.get())) {

case ccRSAKeyPublic: {

Vector<uint8_t> modulus;

Vector<uint8_t> publicExponent;

CCCryptorStatus status = getPublicKeyComponents(m_platformKey, modulus, publicExponent);

if (status) {

WTFLogAlways("Couldn't get RSA key components, status %d", status);

return nullptr;

}

return CryptoKeyRSAComponents::createPublic(modulus, publicExponent);

}

case ccRSAKeyPrivate: {

Vector<uint8_t> modulus;

Vector<uint8_t> publicExponent;

CCCryptorStatus status = getPublicKeyComponents(m_platformKey, modulus, publicExponent);

if (status) {

WTFLogAlways("Couldn't get RSA key components, status %d", status);

return nullptr;

}

Vector<uint8_t> privateExponent;

CryptoKeyRSAComponents::PrimeInfo firstPrimeInfo;

CryptoKeyRSAComponents::PrimeInfo secondPrimeInfo;

Vector<CryptoKeyRSAComponents::PrimeInfo> otherPrimeInfos; // Always empty, CommonCrypto only supports two primes (cf. <rdar://problem/15444074>).

status = getPrivateKeyComponents(m_platformKey, privateExponent, firstPrimeInfo, secondPrimeInfo);

if (status) {

WTFLogAlways("Couldn't get RSA key components, status %d", status);

return nullptr;

}

return CryptoKeyRSAComponents::createPrivateWithAdditionalData(modulus, publicExponent, privateExponent, firstPrimeInfo, secondPrimeInfo, otherPrimeInfos);

}

default:

return nullptr;

}

}

static bool bigIntegerToUInt32(const Vector<uint8_t>& bigInteger, uint32_t& result)

{

result = 0;

for (size_t i = 0; i + 4 < bigInteger.size(); ++i) {

if (bigInteger[i])

return false; // Too big to fit in 32 bits.

}

for (size_t i = bigInteger.size() > 4 ? bigInteger.size() - 4 : 0; i < bigInteger.size(); ++i) {

result <<= 8;

result += bigInteger[i];

}

return true;

}

// FIXME: We should use WorkQueue here instead of dispatch_async once WebKitSubtleCrypto is deprecated.

// https://bugs.webkit.org/show_bug.cgi?id=164943

void CryptoKeyRSA::generatePair(CryptoAlgorithmIdentifier algorithm, CryptoAlgorithmIdentifier hash, bool hasHash, unsigned modulusLength, const Vector<uint8_t>& publicExponent, bool extractable, CryptoKeyUsageBitmap usage, KeyPairCallback&& callback, VoidCallback&& failureCallback, ScriptExecutionContext* context)

{

uint32_t e;

if (!bigIntegerToUInt32(publicExponent, e)) {

// Adding support is tracked as <rdar://problem/15444034>.

WTFLogAlways("Public exponent is too big, not supported");

failureCallback();

return;

}

__block auto blockCallback(WTFMove(callback));

__block auto blockFailureCallback(WTFMove(failureCallback));

auto contextIdentifier = context->contextIdentifier();

dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{

CCRSACryptorRef ccPublicKey = nullptr;

CCRSACryptorRef ccPrivateKey = nullptr;

CCCryptorStatus status = CCRSACryptorGeneratePair(modulusLength, e, &ccPublicKey, &ccPrivateKey);

if (status) {

WTFLogAlways("Could not generate a key pair, status %d", status);

ScriptExecutionContext::postTaskTo(contextIdentifier, [callback = WTFMove(blockCallback), failureCallback = WTFMove(blockFailureCallback)](auto&) {

failureCallback();

});

return;

}

ScriptExecutionContext::postTaskTo(contextIdentifier, [algorithm, hash, hasHash, extractable, usage, callback = WTFMove(blockCallback), failureCallback = WTFMove(blockFailureCallback), ccPublicKey = PlatformRSAKeyContainer(ccPublicKey), ccPrivateKey = PlatformRSAKeyContainer(ccPrivateKey)](auto&) mutable {

auto publicKey = CryptoKeyRSA::create(algorithm, hash, hasHash, CryptoKeyType::Public, WTFMove(ccPublicKey), true, usage);

auto privateKey = CryptoKeyRSA::create(algorithm, hash, hasHash, CryptoKeyType::Private, WTFMove(ccPrivateKey), extractable, usage);

callback(CryptoKeyPair { WTFMove(publicKey), WTFMove(privateKey) });

});

});

}

RefPtr<CryptoKeyRSA> CryptoKeyRSA::importSpki(CryptoAlgorithmIdentifier identifier, std::optional<CryptoAlgorithmIdentifier> hash, Vector<uint8_t>&& keyData, bool extractable, CryptoKeyUsageBitmap usages)

{

// The current SecLibrary cannot import a SPKI format binary. Hence, we need to strip out the SPKI header.

// This hack can be removed when <rdar://problem/29523286> is resolved.

// The header format we assume is: SequenceMark(1) + Length(?) + rsaEncryption(15) + BitStringMark(1) + Length(?) + InitialOctet(1).

// The header format could be varied. However since we don't have a full-fledged ASN.1 encoder/decoder, we want to restrict it to

// the most common one for now.

// Per https://tools.ietf.org/html/rfc5280#section-4.1. subjectPublicKeyInfo.

size_t headerSize = 1;

if (keyData.size() < headerSize + 1)

return nullptr;

headerSize += bytesUsedToEncodedLength(keyData[headerSize]) + sizeof(RSAOIDHeader) + sizeof(BitStringMark);

if (keyData.size() < headerSize + 1)

return nullptr;

headerSize += bytesUsedToEncodedLength(keyData[headerSize]) + sizeof(InitialOctet);

CCRSACryptorRef ccPublicKey = nullptr;

if (CCRSACryptorImport(keyData.data() + headerSize, keyData.size() - headerSize, &ccPublicKey))

return nullptr;

// Notice: CryptoAlgorithmIdentifier::SHA_1 is just a placeholder. It should not have any effect if hash is std::nullopt.

return adoptRef(new CryptoKeyRSA(identifier, hash.value_or(CryptoAlgorithmIdentifier::SHA_1), !!hash, CryptoKeyType::Public, PlatformRSAKeyContainer(ccPublicKey), extractable, usages));

}

ExceptionOr<Vector<uint8_t>> CryptoKeyRSA::exportSpki() const

{

if (type() != CryptoKeyType::Public)

return Exception { InvalidAccessError };

// The current SecLibrary cannot output a valid SPKI format binary. Hence, we need the following hack.

// This hack can be removed when <rdar://problem/29523286> is resolved.

// Estimated size in produced bytes format. Per https://tools.ietf.org/html/rfc3279#section-2.3.1. RSAPublicKey.

// O(size) = Sequence(1) + Length(3) + Integer(1) + Length(3) + Modulus + Integer(1) + Length(3) + Exponent

Vector<uint8_t> keyBytes(keySizeInBits() / 4);

size_t keySize = keyBytes.size();

if (CCRSACryptorExport(platformKey(), keyBytes.data(), &keySize))

return Exception { OperationError };

keyBytes.shrink(keySize);

// RSAOIDHeader + BitStringMark + Length + keySize + InitialOctet

size_t totalSize = sizeof(RSAOIDHeader) + bytesNeededForEncodedLength(keySize + 1) + keySize + 2;

// Per https://tools.ietf.org/html/rfc5280#section-4.1. subjectPublicKeyInfo.

Vector<uint8_t> result;

result.reserveCapacity(totalSize + bytesNeededForEncodedLength(totalSize) + 1);

result.append(SequenceMark);

addEncodedASN1Length(result, totalSize);

result.append(RSAOIDHeader, sizeof(RSAOIDHeader));

result.append(BitStringMark);

addEncodedASN1Length(result, keySize + 1);

result.append(InitialOctet);

result.append(keyBytes.data(), keyBytes.size());

return WTFMove(result);

}

RefPtr<CryptoKeyRSA> CryptoKeyRSA::importPkcs8(CryptoAlgorithmIdentifier identifier, std::optional<CryptoAlgorithmIdentifier> hash, Vector<uint8_t>&& keyData, bool extractable, CryptoKeyUsageBitmap usages)

{

// The current SecLibrary cannot import a PKCS8 format binary. Hence, we need to strip out the PKCS8 header.

// This hack can be removed when <rdar://problem/29523286> is resolved.

// The header format we assume is: SequenceMark(1) + Length(?) + Version(3) + rsaEncryption(15) + OctetStringMark(1) + Length(?).

// The header format could be varied. However since we don't have a full-fledged ASN.1 encoder/decoder, we want to restrict it to

// the most common one for now.

// Per https://tools.ietf.org/html/rfc5208#section-5. PrivateKeyInfo.

// We also assume there is no optional parameters.

size_t headerSize = 1;

if (keyData.size() < headerSize + 1)

return nullptr;

headerSize += bytesUsedToEncodedLength(keyData[headerSize]) + sizeof(Version) + sizeof(RSAOIDHeader) + sizeof(OctetStringMark);

if (keyData.size() < headerSize + 1)

return nullptr;

headerSize += bytesUsedToEncodedLength(keyData[headerSize]);

CCRSACryptorRef ccPrivateKey = nullptr;

if (CCRSACryptorImport(keyData.data() + headerSize, keyData.size() - headerSize, &ccPrivateKey))

return nullptr;

// Notice: CryptoAlgorithmIdentifier::SHA_1 is just a placeholder. It should not have any effect if hash is std::nullopt.

return adoptRef(new CryptoKeyRSA(identifier, hash.value_or(CryptoAlgorithmIdentifier::SHA_1), !!hash, CryptoKeyType::Private, PlatformRSAKeyContainer(ccPrivateKey), extractable, usages));

}

ExceptionOr<Vector<uint8_t>> CryptoKeyRSA::exportPkcs8() const

{

if (type() != CryptoKeyType::Private)

return Exception { InvalidAccessError };

// The current SecLibrary cannot output a valid PKCS8 format binary. Hence, we need the following hack.

// This hack can be removed when <rdar://problem/29523286> is resolved.

// Estimated size in produced bytes format. Per https://tools.ietf.org/html/rfc3447#appendix-A.1.2. RSAPrivateKey.

// O(size) = Sequence(1) + Length(3) + Integer(1) + Length(3) + Modulus + Integer(1) + Length(3) + publicExponent + Integer(1) + Length(3) +

// privateExponent + Integer(1) + Length(3) + prime1 + Integer(1) + Length(3) + prime2 + Integer(1) + Length(3) + exponent1 + Integer(1) +

// Length(3) + exponent2 + Integer(1) + Length(3) + coefficient.

Vector<uint8_t> keyBytes(keySizeInBits());

size_t keySize = keyBytes.size();

if (CCRSACryptorExport(platformKey(), keyBytes.data(), &keySize))

return Exception { OperationError };

keyBytes.shrink(keySize);

// Version + RSAOIDHeader + OctetStringMark + Length + keySize

size_t totalSize = sizeof(Version) + sizeof(RSAOIDHeader) + bytesNeededForEncodedLength(keySize) + keySize + 1;

// Per https://tools.ietf.org/html/rfc5208#section-5. PrivateKeyInfo.

Vector<uint8_t> result;

result.reserveCapacity(totalSize + bytesNeededForEncodedLength(totalSize) + 1);

result.append(SequenceMark);

addEncodedASN1Length(result, totalSize);

result.append(Version, sizeof(Version));

result.append(RSAOIDHeader, sizeof(RSAOIDHeader));

result.append(OctetStringMark);

addEncodedASN1Length(result, keySize);

result.append(keyBytes.data(), keyBytes.size());

return WTFMove(result);

}

} // namespace WebCore

#endif // ENABLE(WEB_CRYPTO)