NS_IMETHODIMP
nsRandomGenerator::GenerateRandomBytes(uint32_t aLength,
uint8_t** aBuffer)
{
NS_ENSURE_ARG_POINTER(aBuffer);
*aBuffer = nullptr;
nsNSSShutDownPreventionLock locker;
if (isAlreadyShutDown()) {
return NS_ERROR_NOT_AVAILABLE;
}
mozilla::UniquePK11SlotInfo slot(PK11_GetInternalSlot());
if (!slot) {
return NS_ERROR_FAILURE;
}
auto buf = static_cast<uint8_t*>(moz_xmalloc(aLength));
if (!buf) {
return NS_ERROR_OUT_OF_MEMORY;
}
SECStatus srv = PK11_GenerateRandomOnSlot(slot.get(), buf, aLength);
if (srv != SECSuccess) {
free(buf);
return NS_ERROR_FAILURE;
}
*aBuffer = buf;
return NS_OK;
}
static SECStatus
tls13_AntiReplayKeyGen()
{
PRUint8 buf[32];
SECItem keyItem = { siBuffer, buf, sizeof(buf) };
PK11SlotInfo *slot;
SECStatus rv;
slot = PK11_GetInternalSlot();
if (!slot) {
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
rv = PK11_GenerateRandomOnSlot(slot, buf, sizeof(buf));
if (rv != SECSuccess) {
goto loser;
}
ssl_anti_replay.key = PK11_ImportSymKey(slot, CKM_NSS_HKDF_SHA256,
PK11_OriginUnwrap, CKA_DERIVE,
&keyItem, NULL);
if (!ssl_anti_replay.key) {
goto loser;
}
PK11_FreeSlot(slot);
return SECSuccess;
loser:
PK11_FreeSlot(slot);
return SECFailure;
}
// Implement NSPR-based crypto algorithms
static int nr_crypto_nss_random_bytes(UCHAR *buf, int len) {
ScopedPK11SlotInfo slot(PK11_GetInternalSlot());
if (!slot)
return R_INTERNAL;
SECStatus rv = PK11_GenerateRandomOnSlot(slot, buf, len);
if (rv != SECSuccess)
return R_INTERNAL;
return 0;
}
// Convert a Private Key object into an opaque key handle, using AES Key Wrap
// with the long-lived aPersistentKey mixed with aAppParam to convert aPrivKey.
// The key handle's format is version || saltLen || salt || wrappedPrivateKey
static UniqueSECItem
KeyHandleFromPrivateKey(const UniquePK11SlotInfo& aSlot,
const UniquePK11SymKey& aPersistentKey,
uint8_t* aAppParam, uint32_t aAppParamLen,
const UniqueSECKEYPrivateKey& aPrivKey,
const nsNSSShutDownPreventionLock&)
{
MOZ_ASSERT(aSlot);
MOZ_ASSERT(aPersistentKey);
MOZ_ASSERT(aAppParam);
MOZ_ASSERT(aPrivKey);
if (NS_WARN_IF(!aSlot || !aPersistentKey || !aPrivKey || !aAppParam)) {
return nullptr;
}
// Generate a random salt
uint8_t saltParam[kSaltByteLen];
SECStatus srv = PK11_GenerateRandomOnSlot(aSlot.get(), saltParam,
sizeof(saltParam));
if (NS_WARN_IF(srv != SECSuccess)) {
MOZ_LOG(gNSSTokenLog, LogLevel::Warning,
("Failed to generate a salt, NSS error #%d", PORT_GetError()));
return nullptr;
}
// Prepare the HKDF (https://tools.ietf.org/html/rfc5869)
CK_NSS_HKDFParams hkdfParams = { true, saltParam, sizeof(saltParam),
true, aAppParam, aAppParamLen };
SECItem kdfParams = { siBuffer, (unsigned char*)&hkdfParams,
sizeof(hkdfParams) };
// Derive a wrapping key from aPersistentKey, the salt, and the aAppParam.
// CKM_AES_KEY_GEN and CKA_WRAP are key type and usage attributes of the
// derived symmetric key and don't matter because we ignore them anyway.
UniquePK11SymKey wrapKey(PK11_Derive(aPersistentKey.get(), CKM_NSS_HKDF_SHA256,
&kdfParams, CKM_AES_KEY_GEN, CKA_WRAP,
kWrappingKeyByteLen));
if (NS_WARN_IF(!wrapKey.get())) {
MOZ_LOG(gNSSTokenLog, LogLevel::Warning,
("Failed to derive a wrapping key, NSS error #%d", PORT_GetError()));
return nullptr;
}
UniqueSECItem wrappedKey(::SECITEM_AllocItem(/* default arena */ nullptr,
/* no buffer */ nullptr,
kWrappedKeyBufLen));
if (NS_WARN_IF(!wrappedKey)) {
MOZ_LOG(gNSSTokenLog, LogLevel::Warning, ("Failed to allocate memory"));
return nullptr;
}
UniqueSECItem param(PK11_ParamFromIV(CKM_NSS_AES_KEY_WRAP_PAD,
/* default IV */ nullptr ));
srv = PK11_WrapPrivKey(aSlot.get(), wrapKey.get(), aPrivKey.get(),
CKM_NSS_AES_KEY_WRAP_PAD, param.get(), wrappedKey.get(),
/* wincx */ nullptr);
if (NS_WARN_IF(srv != SECSuccess)) {
MOZ_LOG(gNSSTokenLog, LogLevel::Warning,
("Failed to wrap U2F key, NSS error #%d", PORT_GetError()));
return nullptr;
}
// Concatenate the salt and the wrapped Private Key together
mozilla::dom::CryptoBuffer keyHandleBuf;
if (NS_WARN_IF(!keyHandleBuf.SetCapacity(wrappedKey.get()->len + sizeof(saltParam) + 2,
mozilla::fallible))) {
MOZ_LOG(gNSSTokenLog, LogLevel::Warning, ("Failed to allocate memory"));
return nullptr;
}
// It's OK to ignore the return values here because we're writing into
// pre-allocated space
keyHandleBuf.AppendElement(SoftTokenHandle::Version1, mozilla::fallible);
keyHandleBuf.AppendElement(sizeof(saltParam), mozilla::fallible);
keyHandleBuf.AppendElements(saltParam, sizeof(saltParam), mozilla::fallible);
keyHandleBuf.AppendSECItem(wrappedKey.get());
UniqueSECItem keyHandle(::SECITEM_AllocItem(nullptr, nullptr, 0));
if (NS_WARN_IF(!keyHandle)) {
MOZ_LOG(gNSSTokenLog, LogLevel::Warning, ("Failed to allocate memory"));
return nullptr;
}
if (NS_WARN_IF(!keyHandleBuf.ToSECItem(/* default arena */ nullptr, keyHandle.get()))) {
MOZ_LOG(gNSSTokenLog, LogLevel::Warning, ("Failed to allocate memory"));
return nullptr;
}
return keyHandle;
}
static nsresult
GetAttestationCertificate(const UniquePK11SlotInfo& aSlot,
/*out*/ UniqueSECKEYPrivateKey& aAttestPrivKey,
/*out*/ UniqueCERTCertificate& aAttestCert,
const nsNSSShutDownPreventionLock& locker)
{
MOZ_ASSERT(aSlot);
if (NS_WARN_IF(!aSlot)) {
return NS_ERROR_INVALID_ARG;
}
UniqueSECKEYPublicKey pubKey;
// Construct an ephemeral keypair for this Attestation Certificate
nsresult rv = GenEcKeypair(aSlot, aAttestPrivKey, pubKey, locker);
if (NS_WARN_IF(NS_FAILED(rv) || !aAttestPrivKey || !pubKey)) {
MOZ_LOG(gNSSTokenLog, LogLevel::Warning,
("Failed to gen keypair, NSS error #%d", PORT_GetError()));
return NS_ERROR_FAILURE;
}
// Construct the Attestation Certificate itself
UniqueCERTName subjectName(CERT_AsciiToName(kAttestCertSubjectName.get()));
if (NS_WARN_IF(!subjectName)) {
MOZ_LOG(gNSSTokenLog, LogLevel::Warning,
("Failed to set subject name, NSS error #%d", PORT_GetError()));
return NS_ERROR_FAILURE;
}
UniqueCERTSubjectPublicKeyInfo spki(
SECKEY_CreateSubjectPublicKeyInfo(pubKey.get()));
if (NS_WARN_IF(!spki)) {
MOZ_LOG(gNSSTokenLog, LogLevel::Warning,
("Failed to set SPKI, NSS error #%d", PORT_GetError()));
return NS_ERROR_FAILURE;
}
UniqueCERTCertificateRequest certreq(
CERT_CreateCertificateRequest(subjectName.get(), spki.get(), nullptr));
if (NS_WARN_IF(!certreq)) {
MOZ_LOG(gNSSTokenLog, LogLevel::Warning,
("Failed to gen CSR, NSS error #%d", PORT_GetError()));
return NS_ERROR_FAILURE;
}
PRTime now = PR_Now();
PRTime notBefore = now - kExpirationSlack;
PRTime notAfter = now + kExpirationLife;
UniqueCERTValidity validity(CERT_CreateValidity(notBefore, notAfter));
if (NS_WARN_IF(!validity)) {
MOZ_LOG(gNSSTokenLog, LogLevel::Warning,
("Failed to gen validity, NSS error #%d", PORT_GetError()));
return NS_ERROR_FAILURE;
}
unsigned long serial;
unsigned char* serialBytes =
mozilla::BitwiseCast<unsigned char*, unsigned long*>(&serial);
SECStatus srv = PK11_GenerateRandomOnSlot(aSlot.get(), serialBytes,
sizeof(serial));
if (NS_WARN_IF(srv != SECSuccess)) {
MOZ_LOG(gNSSTokenLog, LogLevel::Warning,
("Failed to gen serial, NSS error #%d", PORT_GetError()));
return NS_ERROR_FAILURE;
}
// Ensure that the most significant bit isn't set (which would
// indicate a negative number, which isn't valid for serial
// numbers).
serialBytes[0] &= 0x7f;
// Also ensure that the least significant bit on the most
// significant byte is set (to prevent a leading zero byte,
// which also wouldn't be valid).
serialBytes[0] |= 0x01;
aAttestCert = UniqueCERTCertificate(
CERT_CreateCertificate(serial, subjectName.get(), validity.get(),
certreq.get()));
if (NS_WARN_IF(!aAttestCert)) {
MOZ_LOG(gNSSTokenLog, LogLevel::Warning,
("Failed to gen certificate, NSS error #%d", PORT_GetError()));
return NS_ERROR_FAILURE;
}
PLArenaPool* arena = aAttestCert->arena;
srv = SECOID_SetAlgorithmID(arena, &aAttestCert->signature,
SEC_OID_ANSIX962_ECDSA_SHA256_SIGNATURE,
/* wincx */ nullptr);
if (NS_WARN_IF(srv != SECSuccess)) {
return NS_ERROR_FAILURE;
}
// Set version to X509v3.
*(aAttestCert->version.data) = SEC_CERTIFICATE_VERSION_3;
aAttestCert->version.len = 1;
SECItem innerDER = { siBuffer, nullptr, 0 };
if (NS_WARN_IF(!SEC_ASN1EncodeItem(arena, &innerDER, aAttestCert.get(),
SEC_ASN1_GET(CERT_CertificateTemplate)))) {
return NS_ERROR_FAILURE;
}
SECItem* signedCert = PORT_ArenaZNew(arena, SECItem);
if (NS_WARN_IF(!signedCert)) {
return NS_ERROR_FAILURE;
}
srv = SEC_DerSignData(arena, signedCert, innerDER.data, innerDER.len,
aAttestPrivKey.get(),
SEC_OID_ANSIX962_ECDSA_SHA256_SIGNATURE);
if (NS_WARN_IF(srv != SECSuccess)) {
return NS_ERROR_FAILURE;
}
aAttestCert->derCert = *signedCert;
MOZ_LOG(gNSSTokenLog, LogLevel::Debug,
("U2F Soft Token attestation certificate generated."));
return NS_OK;
}
// NSS exports private EC keys without the CKA_EC_POINT attribute, i.e. the
// public value. To properly export the private key to JWK or PKCS #8 we need
// the public key data though and so we use this method to augment a private
// key with data from the given public key.
nsresult
CryptoKey::AddPublicKeyData(SECKEYPublicKey* aPublicKey)
{
// This should be a private key.
MOZ_ASSERT(GetKeyType() == PRIVATE);
// There should be a private NSS key with type 'EC'.
MOZ_ASSERT(mPrivateKey && mPrivateKey->keyType == ecKey);
// The given public key should have the same key type.
MOZ_ASSERT(aPublicKey->keyType == mPrivateKey->keyType);
nsNSSShutDownPreventionLock locker;
ScopedPK11SlotInfo slot(PK11_GetInternalSlot());
if (!slot) {
return NS_ERROR_DOM_OPERATION_ERR;
}
// Generate a random 160-bit object ID.
ScopedSECItem objID(::SECITEM_AllocItem(nullptr, nullptr, 20));
SECStatus rv = PK11_GenerateRandomOnSlot(slot, objID->data, objID->len);
if (rv != SECSuccess) {
return NS_ERROR_DOM_OPERATION_ERR;
}
// Read EC params.
ScopedSECItem params(::SECITEM_AllocItem(nullptr, nullptr, 0));
rv = PK11_ReadRawAttribute(PK11_TypePrivKey, mPrivateKey, CKA_EC_PARAMS,
params);
if (rv != SECSuccess) {
return NS_ERROR_DOM_OPERATION_ERR;
}
// Read private value.
ScopedSECItem value(::SECITEM_AllocItem(nullptr, nullptr, 0));
rv = PK11_ReadRawAttribute(PK11_TypePrivKey, mPrivateKey, CKA_VALUE, value);
if (rv != SECSuccess) {
return NS_ERROR_DOM_OPERATION_ERR;
}
SECItem* point = &aPublicKey->u.ec.publicValue;
CK_OBJECT_CLASS privateKeyValue = CKO_PRIVATE_KEY;
CK_BBOOL falseValue = CK_FALSE;
CK_KEY_TYPE ecValue = CKK_EC;
CK_ATTRIBUTE keyTemplate[9] = {
{ CKA_CLASS, &privateKeyValue, sizeof(privateKeyValue) },
{ CKA_KEY_TYPE, &ecValue, sizeof(ecValue) },
{ CKA_TOKEN, &falseValue, sizeof(falseValue) },
{ CKA_SENSITIVE, &falseValue, sizeof(falseValue) },
{ CKA_PRIVATE, &falseValue, sizeof(falseValue) },
{ CKA_ID, objID->data, objID->len },
{ CKA_EC_PARAMS, params->data, params->len },
{ CKA_EC_POINT, point->data, point->len },
{ CKA_VALUE, value->data, value->len },
};
mPrivateKey = PrivateKeyFromPrivateKeyTemplate(objID, keyTemplate,
PR_ARRAY_SIZE(keyTemplate));
NS_ENSURE_TRUE(mPrivateKey, NS_ERROR_DOM_OPERATION_ERR);
return NS_OK;
}
nsresult Generate()
{
nsresult rv;
// Get the key slot for generation later
UniquePK11SlotInfo slot(PK11_GetInternalKeySlot());
if (!slot) {
return mozilla::psm::GetXPCOMFromNSSError(PR_GetError());
}
// Remove existing certs with this name (if any)
rv = RemoveExisting();
if (NS_FAILED(rv)) {
return rv;
}
// Generate a new cert
NS_NAMED_LITERAL_CSTRING(commonNamePrefix, "CN=");
nsAutoCString subjectNameStr(commonNamePrefix + mNickname);
UniqueCERTName subjectName(CERT_AsciiToName(subjectNameStr.get()));
if (!subjectName) {
return mozilla::psm::GetXPCOMFromNSSError(PR_GetError());
}
// Use the well-known NIST P-256 curve
SECOidData* curveOidData = SECOID_FindOIDByTag(SEC_OID_SECG_EC_SECP256R1);
if (!curveOidData) {
return mozilla::psm::GetXPCOMFromNSSError(PR_GetError());
}
// Get key params from the curve
ScopedAutoSECItem keyParams(2 + curveOidData->oid.len);
keyParams.data[0] = SEC_ASN1_OBJECT_ID;
keyParams.data[1] = curveOidData->oid.len;
memcpy(keyParams.data + 2, curveOidData->oid.data, curveOidData->oid.len);
// Generate cert key pair
SECKEYPublicKey* tempPublicKey;
UniqueSECKEYPrivateKey privateKey(
PK11_GenerateKeyPair(slot.get(), CKM_EC_KEY_PAIR_GEN, &keyParams,
&tempPublicKey, true /* token */,
true /* sensitive */, nullptr));
UniqueSECKEYPublicKey publicKey(tempPublicKey);
tempPublicKey = nullptr;
if (!privateKey || !publicKey) {
return mozilla::psm::GetXPCOMFromNSSError(PR_GetError());
}
// Create subject public key info and cert request
UniqueCERTSubjectPublicKeyInfo spki(
SECKEY_CreateSubjectPublicKeyInfo(publicKey.get()));
if (!spki) {
return mozilla::psm::GetXPCOMFromNSSError(PR_GetError());
}
UniqueCERTCertificateRequest certRequest(
CERT_CreateCertificateRequest(subjectName.get(), spki.get(), nullptr));
if (!certRequest) {
return mozilla::psm::GetXPCOMFromNSSError(PR_GetError());
}
// Valid from one day before to 1 year after
static const PRTime oneDay = PRTime(PR_USEC_PER_SEC)
* PRTime(60) // sec
* PRTime(60) // min
* PRTime(24); // hours
PRTime now = PR_Now();
PRTime notBefore = now - oneDay;
PRTime notAfter = now + (PRTime(365) * oneDay);
UniqueCERTValidity validity(CERT_CreateValidity(notBefore, notAfter));
if (!validity) {
return mozilla::psm::GetXPCOMFromNSSError(PR_GetError());
}
// Generate random serial
unsigned long serial;
// This serial in principle could collide, but it's unlikely
rv = MapSECStatus(PK11_GenerateRandomOnSlot(
slot.get(), BitwiseCast<unsigned char*, unsigned long*>(&serial),
sizeof(serial)));
if (NS_FAILED(rv)) {
return rv;
}
// Create the cert from these pieces
UniqueCERTCertificate cert(
CERT_CreateCertificate(serial, subjectName.get(), validity.get(),
certRequest.get()));
if (!cert) {
return mozilla::psm::GetXPCOMFromNSSError(PR_GetError());
}
// Update the cert version to X509v3
if (!cert->version.data) {
return NS_ERROR_INVALID_POINTER;
}
*(cert->version.data) = SEC_CERTIFICATE_VERSION_3;
cert->version.len = 1;
// Set cert signature algorithm
PLArenaPool* arena = cert->arena;
if (!arena) {
return NS_ERROR_INVALID_POINTER;
}
rv = MapSECStatus(
SECOID_SetAlgorithmID(arena, &cert->signature,
SEC_OID_ANSIX962_ECDSA_SHA256_SIGNATURE, 0));
if (NS_FAILED(rv)) {
return rv;
}
// Encode and self-sign the cert
UniqueSECItem certDER(
SEC_ASN1EncodeItem(nullptr, nullptr, cert.get(),
SEC_ASN1_GET(CERT_CertificateTemplate)));
if (!certDER) {
return mozilla::psm::GetXPCOMFromNSSError(PR_GetError());
}
rv = MapSECStatus(
SEC_DerSignData(arena, &cert->derCert, certDER->data, certDER->len,
privateKey.get(),
SEC_OID_ANSIX962_ECDSA_SHA256_SIGNATURE));
if (NS_FAILED(rv)) {
return rv;
}
// Create a CERTCertificate from the signed data
UniqueCERTCertificate certFromDER(
CERT_NewTempCertificate(CERT_GetDefaultCertDB(), &cert->derCert, nullptr,
true /* perm */, true /* copyDER */));
if (!certFromDER) {
return mozilla::psm::GetXPCOMFromNSSError(PR_GetError());
}
// Save the cert in the DB
rv = MapSECStatus(PK11_ImportCert(slot.get(), certFromDER.get(),
CK_INVALID_HANDLE, mNickname.get(),
false /* unused */));
if (NS_FAILED(rv)) {
return rv;
}
// We should now have cert in the DB, read it back in nsIX509Cert form
return GetFromDB();
}
RefPtr<DtlsIdentity> DtlsIdentity::Generate() {
UniquePK11SlotInfo slot(PK11_GetInternalSlot());
if (!slot) {
return nullptr;
}
uint8_t random_name[16];
SECStatus rv = PK11_GenerateRandomOnSlot(slot.get(), random_name,
sizeof(random_name));
if (rv != SECSuccess)
return nullptr;
std::string name;
char chunk[3];
for (size_t i = 0; i < sizeof(random_name); ++i) {
SprintfLiteral(chunk, "%.2x", random_name[i]);
name += chunk;
}
std::string subject_name_string = "CN=" + name;
UniqueCERTName subject_name(CERT_AsciiToName(subject_name_string.c_str()));
if (!subject_name) {
return nullptr;
}
unsigned char paramBuf[12]; // OIDs are small
SECItem ecdsaParams = { siBuffer, paramBuf, sizeof(paramBuf) };
SECOidData* oidData = SECOID_FindOIDByTag(SEC_OID_SECG_EC_SECP256R1);
if (!oidData || (oidData->oid.len > (sizeof(paramBuf) - 2))) {
return nullptr;
}
ecdsaParams.data[0] = SEC_ASN1_OBJECT_ID;
ecdsaParams.data[1] = oidData->oid.len;
memcpy(ecdsaParams.data + 2, oidData->oid.data, oidData->oid.len);
ecdsaParams.len = oidData->oid.len + 2;
SECKEYPublicKey *pubkey;
UniqueSECKEYPrivateKey private_key(
PK11_GenerateKeyPair(slot.get(),
CKM_EC_KEY_PAIR_GEN, &ecdsaParams, &pubkey,
PR_FALSE, PR_TRUE, nullptr));
if (private_key == nullptr)
return nullptr;
UniqueSECKEYPublicKey public_key(pubkey);
pubkey = nullptr;
UniqueCERTSubjectPublicKeyInfo spki(
SECKEY_CreateSubjectPublicKeyInfo(public_key.get()));
if (!spki) {
return nullptr;
}
UniqueCERTCertificateRequest certreq(
CERT_CreateCertificateRequest(subject_name.get(), spki.get(), nullptr));
if (!certreq) {
return nullptr;
}
// From 1 day before todayto 30 days after.
// This is a sort of arbitrary range designed to be valid
// now with some slack in case the other side expects
// some before expiry.
//
// Note: explicit casts necessary to avoid
// warning C4307: '*' : integral constant overflow
static const PRTime oneDay = PRTime(PR_USEC_PER_SEC)
* PRTime(60) // sec
* PRTime(60) // min
* PRTime(24); // hours
PRTime now = PR_Now();
PRTime notBefore = now - oneDay;
PRTime notAfter = now + (PRTime(30) * oneDay);
UniqueCERTValidity validity(CERT_CreateValidity(notBefore, notAfter));
if (!validity) {
return nullptr;
}
unsigned long serial;
// Note: This serial in principle could collide, but it's unlikely
rv = PK11_GenerateRandomOnSlot(slot.get(),
reinterpret_cast<unsigned char *>(&serial),
sizeof(serial));
if (rv != SECSuccess) {
return nullptr;
}
UniqueCERTCertificate certificate(
CERT_CreateCertificate(serial, subject_name.get(), validity.get(),
certreq.get()));
if (!certificate) {
return nullptr;
}
PLArenaPool *arena = certificate->arena;
rv = SECOID_SetAlgorithmID(arena, &certificate->signature,
SEC_OID_ANSIX962_ECDSA_SHA256_SIGNATURE, 0);
if (rv != SECSuccess)
return nullptr;
// Set version to X509v3.
*(certificate->version.data) = SEC_CERTIFICATE_VERSION_3;
certificate->version.len = 1;
SECItem innerDER;
innerDER.len = 0;
innerDER.data = nullptr;
if (!SEC_ASN1EncodeItem(arena, &innerDER, certificate.get(),
SEC_ASN1_GET(CERT_CertificateTemplate))) {
return nullptr;
}
SECItem *signedCert = PORT_ArenaZNew(arena, SECItem);
if (!signedCert) {
return nullptr;
}
rv = SEC_DerSignData(arena, signedCert, innerDER.data, innerDER.len,
private_key.get(),
SEC_OID_ANSIX962_ECDSA_SHA256_SIGNATURE);
if (rv != SECSuccess) {
return nullptr;
}
certificate->derCert = *signedCert;
RefPtr<DtlsIdentity> identity = new DtlsIdentity(Move(private_key),
Move(certificate),
ssl_kea_ecdh);
return identity.forget();
}