зеркало из https://github.com/mozilla/gecko-dev.git
888 строки
32 KiB
C++
888 строки
32 KiB
C++
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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/* vim:set ts=2 sw=2 sts=2 et cindent: */
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/* This Source Code Form is subject to the terms of the Mozilla Public
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* License, v. 2.0. If a copy of the MPL was not distributed with this file,
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* You can obtain one at http://mozilla.org/MPL/2.0/. */
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#include "mozilla/dom/U2FSoftTokenManager.h"
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#include "CryptoBuffer.h"
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#include "mozilla/Base64.h"
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#include "mozilla/Casting.h"
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#include "nsNSSComponent.h"
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#include "nsThreadUtils.h"
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#include "pk11pub.h"
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#include "prerror.h"
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#include "secerr.h"
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#include "WebCryptoCommon.h"
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#define PREF_U2F_NSSTOKEN_COUNTER "security.webauth.softtoken_counter"
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namespace mozilla {
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namespace dom {
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using namespace mozilla;
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using mozilla::dom::CreateECParamsForCurve;
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const nsCString U2FSoftTokenManager::mSecretNickname =
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NS_LITERAL_CSTRING("U2F_NSSTOKEN");
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const nsString U2FSoftTokenManager::mVersion =
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NS_LITERAL_STRING("U2F_V2");
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namespace {
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NS_NAMED_LITERAL_CSTRING(kAttestCertSubjectName, "CN=Firefox U2F Soft Token");
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// This U2F-compatible soft token uses FIDO U2F-compatible ECDSA keypairs
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// on the SEC_OID_SECG_EC_SECP256R1 curve. When asked to Register, it will
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// generate and return a new keypair KP, where the private component is wrapped
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// using AES-KW with the 128-bit mWrappingKey to make an opaque "key handle".
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// In other words, Register yields { KP_pub, AES-KW(KP_priv, key=mWrappingKey) }
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//
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// The value mWrappingKey is long-lived; it is persisted as part of the NSS DB
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// for the current profile. The attestation certificates that are produced are
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// ephemeral to counteract profiling. They have little use for a soft-token
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// at any rate, but are required by the specification.
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const uint32_t kParamLen = 32;
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const uint32_t kPublicKeyLen = 65;
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const uint32_t kWrappedKeyBufLen = 256;
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const uint32_t kWrappingKeyByteLen = 128/8;
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const uint32_t kSaltByteLen = 64/8;
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const uint32_t kVersion1KeyHandleLen = 162;
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NS_NAMED_LITERAL_STRING(kEcAlgorithm, WEBCRYPTO_NAMED_CURVE_P256);
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const PRTime kOneDay = PRTime(PR_USEC_PER_SEC)
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* PRTime(60) // sec
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* PRTime(60) // min
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* PRTime(24); // hours
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const PRTime kExpirationSlack = kOneDay; // Pre-date for clock skew
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const PRTime kExpirationLife = kOneDay;
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static mozilla::LazyLogModule gNSSTokenLog("webauth_u2f");
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enum SoftTokenHandle {
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Version1 = 0,
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};
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}
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U2FSoftTokenManager::U2FSoftTokenManager(uint32_t aCounter)
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: mInitialized(false),
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mCounter(aCounter)
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{}
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U2FSoftTokenManager::~U2FSoftTokenManager()
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{
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nsNSSShutDownPreventionLock locker;
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if (isAlreadyShutDown()) {
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return;
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}
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destructorSafeDestroyNSSReference();
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shutdown(ShutdownCalledFrom::Object);
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}
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void
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U2FSoftTokenManager::virtualDestroyNSSReference()
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{
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destructorSafeDestroyNSSReference();
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}
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void
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U2FSoftTokenManager::destructorSafeDestroyNSSReference()
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{
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mWrappingKey = nullptr;
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}
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/**
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* Gets the first key with the given nickname from the given slot. Any other
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* keys found are not returned.
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* PK11_GetNextSymKey() should not be called on the returned key.
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*
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* @param aSlot Slot to search.
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* @param aNickname Nickname the key should have.
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* @return The first key found. nullptr if no key could be found.
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*/
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static UniquePK11SymKey
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GetSymKeyByNickname(const UniquePK11SlotInfo& aSlot,
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const nsCString& aNickname,
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const nsNSSShutDownPreventionLock&)
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{
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MOZ_ASSERT(aSlot);
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if (NS_WARN_IF(!aSlot)) {
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return nullptr;
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}
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MOZ_LOG(gNSSTokenLog, LogLevel::Debug,
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("Searching for a symmetric key named %s", aNickname.get()));
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UniquePK11SymKey keyListHead(
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PK11_ListFixedKeysInSlot(aSlot.get(), const_cast<char*>(aNickname.get()),
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/* wincx */ nullptr));
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if (NS_WARN_IF(!keyListHead)) {
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MOZ_LOG(gNSSTokenLog, LogLevel::Debug, ("Symmetric key not found."));
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return nullptr;
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}
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// Sanity check PK11_ListFixedKeysInSlot() only returns keys with the correct
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// nickname.
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MOZ_ASSERT(aNickname ==
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UniquePORTString(PK11_GetSymKeyNickname(keyListHead.get())).get());
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MOZ_LOG(gNSSTokenLog, LogLevel::Debug, ("Symmetric key found!"));
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// Free any remaining keys in the key list.
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UniquePK11SymKey freeKey(PK11_GetNextSymKey(keyListHead.get()));
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while (freeKey) {
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freeKey = UniquePK11SymKey(PK11_GetNextSymKey(freeKey.get()));
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}
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return keyListHead;
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}
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static nsresult
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GenEcKeypair(const UniquePK11SlotInfo& aSlot,
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/*out*/ UniqueSECKEYPrivateKey& aPrivKey,
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/*out*/ UniqueSECKEYPublicKey& aPubKey,
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const nsNSSShutDownPreventionLock&)
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{
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MOZ_ASSERT(aSlot);
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if (NS_WARN_IF(!aSlot)) {
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return NS_ERROR_INVALID_ARG;
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}
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UniquePLArenaPool arena(PORT_NewArena(DER_DEFAULT_CHUNKSIZE));
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if (NS_WARN_IF(!arena)) {
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return NS_ERROR_OUT_OF_MEMORY;
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}
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// Set the curve parameters; keyParams belongs to the arena memory space
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SECItem* keyParams = CreateECParamsForCurve(kEcAlgorithm, arena.get());
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if (NS_WARN_IF(!keyParams)) {
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return NS_ERROR_OUT_OF_MEMORY;
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}
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// Generate a key pair
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CK_MECHANISM_TYPE mechanism = CKM_EC_KEY_PAIR_GEN;
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SECKEYPublicKey* pubKeyRaw;
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aPrivKey = UniqueSECKEYPrivateKey(
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PK11_GenerateKeyPair(aSlot.get(), mechanism, keyParams, &pubKeyRaw,
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/* ephemeral */ false, false,
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/* wincx */ nullptr));
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aPubKey = UniqueSECKEYPublicKey(pubKeyRaw);
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pubKeyRaw = nullptr;
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if (NS_WARN_IF(!aPrivKey.get() || !aPubKey.get())) {
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return NS_ERROR_FAILURE;
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}
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// Check that the public key has the correct length
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if (NS_WARN_IF(aPubKey->u.ec.publicValue.len != kPublicKeyLen)) {
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return NS_ERROR_FAILURE;
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}
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return NS_OK;
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}
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nsresult
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U2FSoftTokenManager::GetOrCreateWrappingKey(const UniquePK11SlotInfo& aSlot,
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const nsNSSShutDownPreventionLock& locker)
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{
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MOZ_ASSERT(aSlot);
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if (NS_WARN_IF(!aSlot)) {
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return NS_ERROR_INVALID_ARG;
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}
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// Search for an existing wrapping key. If we find it,
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// store it for later and mark ourselves initialized.
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mWrappingKey = GetSymKeyByNickname(aSlot, mSecretNickname, locker);
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if (mWrappingKey) {
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MOZ_LOG(gNSSTokenLog, LogLevel::Debug, ("U2F Soft Token Key found."));
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mInitialized = true;
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return NS_OK;
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}
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MOZ_LOG(gNSSTokenLog, LogLevel::Info,
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("No keys found. Generating new U2F Soft Token wrapping key."));
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// We did not find an existing wrapping key, so we generate one in the
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// persistent database (e.g, Token).
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mWrappingKey = UniquePK11SymKey(
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PK11_TokenKeyGenWithFlags(aSlot.get(), CKM_AES_KEY_GEN,
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/* default params */ nullptr,
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kWrappingKeyByteLen,
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/* empty keyid */ nullptr,
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/* flags */ CKF_WRAP | CKF_UNWRAP,
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/* attributes */ PK11_ATTR_TOKEN |
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PK11_ATTR_PRIVATE,
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/* wincx */ nullptr));
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if (NS_WARN_IF(!mWrappingKey)) {
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MOZ_LOG(gNSSTokenLog, LogLevel::Warning,
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("Failed to store wrapping key, NSS error #%d", PORT_GetError()));
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return NS_ERROR_FAILURE;
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}
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SECStatus srv = PK11_SetSymKeyNickname(mWrappingKey.get(),
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mSecretNickname.get());
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if (NS_WARN_IF(srv != SECSuccess)) {
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MOZ_LOG(gNSSTokenLog, LogLevel::Warning,
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("Failed to set nickname, NSS error #%d", PORT_GetError()));
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return NS_ERROR_FAILURE;
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}
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MOZ_LOG(gNSSTokenLog, LogLevel::Debug,
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("Key stored, nickname set to %s.", mSecretNickname.get()));
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GetMainThreadEventTarget()->Dispatch(NS_NewRunnableFunction(
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"dom::U2FSoftTokenManager::GetOrCreateWrappingKey",
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[] () {
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MOZ_ASSERT(NS_IsMainThread());
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Preferences::SetUint(PREF_U2F_NSSTOKEN_COUNTER, 0);
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}));
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return NS_OK;
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}
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static nsresult
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GetAttestationCertificate(const UniquePK11SlotInfo& aSlot,
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/*out*/ UniqueSECKEYPrivateKey& aAttestPrivKey,
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/*out*/ UniqueCERTCertificate& aAttestCert,
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const nsNSSShutDownPreventionLock& locker)
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{
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MOZ_ASSERT(aSlot);
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if (NS_WARN_IF(!aSlot)) {
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return NS_ERROR_INVALID_ARG;
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}
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UniqueSECKEYPublicKey pubKey;
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// Construct an ephemeral keypair for this Attestation Certificate
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nsresult rv = GenEcKeypair(aSlot, aAttestPrivKey, pubKey, locker);
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if (NS_WARN_IF(NS_FAILED(rv) || !aAttestPrivKey || !pubKey)) {
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MOZ_LOG(gNSSTokenLog, LogLevel::Warning,
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("Failed to gen keypair, NSS error #%d", PORT_GetError()));
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return NS_ERROR_FAILURE;
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}
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// Construct the Attestation Certificate itself
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UniqueCERTName subjectName(CERT_AsciiToName(kAttestCertSubjectName.get()));
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if (NS_WARN_IF(!subjectName)) {
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MOZ_LOG(gNSSTokenLog, LogLevel::Warning,
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("Failed to set subject name, NSS error #%d", PORT_GetError()));
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return NS_ERROR_FAILURE;
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}
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UniqueCERTSubjectPublicKeyInfo spki(
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SECKEY_CreateSubjectPublicKeyInfo(pubKey.get()));
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if (NS_WARN_IF(!spki)) {
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MOZ_LOG(gNSSTokenLog, LogLevel::Warning,
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("Failed to set SPKI, NSS error #%d", PORT_GetError()));
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return NS_ERROR_FAILURE;
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}
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UniqueCERTCertificateRequest certreq(
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CERT_CreateCertificateRequest(subjectName.get(), spki.get(), nullptr));
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if (NS_WARN_IF(!certreq)) {
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MOZ_LOG(gNSSTokenLog, LogLevel::Warning,
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("Failed to gen CSR, NSS error #%d", PORT_GetError()));
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return NS_ERROR_FAILURE;
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}
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PRTime now = PR_Now();
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PRTime notBefore = now - kExpirationSlack;
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PRTime notAfter = now + kExpirationLife;
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UniqueCERTValidity validity(CERT_CreateValidity(notBefore, notAfter));
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if (NS_WARN_IF(!validity)) {
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MOZ_LOG(gNSSTokenLog, LogLevel::Warning,
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("Failed to gen validity, NSS error #%d", PORT_GetError()));
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return NS_ERROR_FAILURE;
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}
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unsigned long serial;
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unsigned char* serialBytes =
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mozilla::BitwiseCast<unsigned char*, unsigned long*>(&serial);
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SECStatus srv = PK11_GenerateRandomOnSlot(aSlot.get(), serialBytes,
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sizeof(serial));
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if (NS_WARN_IF(srv != SECSuccess)) {
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MOZ_LOG(gNSSTokenLog, LogLevel::Warning,
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("Failed to gen serial, NSS error #%d", PORT_GetError()));
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return NS_ERROR_FAILURE;
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}
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// Ensure that the most significant bit isn't set (which would
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// indicate a negative number, which isn't valid for serial
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// numbers).
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serialBytes[0] &= 0x7f;
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// Also ensure that the least significant bit on the most
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// significant byte is set (to prevent a leading zero byte,
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// which also wouldn't be valid).
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serialBytes[0] |= 0x01;
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aAttestCert = UniqueCERTCertificate(
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CERT_CreateCertificate(serial, subjectName.get(), validity.get(),
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certreq.get()));
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if (NS_WARN_IF(!aAttestCert)) {
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MOZ_LOG(gNSSTokenLog, LogLevel::Warning,
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("Failed to gen certificate, NSS error #%d", PORT_GetError()));
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return NS_ERROR_FAILURE;
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}
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PLArenaPool* arena = aAttestCert->arena;
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srv = SECOID_SetAlgorithmID(arena, &aAttestCert->signature,
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SEC_OID_ANSIX962_ECDSA_SHA256_SIGNATURE,
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/* wincx */ nullptr);
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if (NS_WARN_IF(srv != SECSuccess)) {
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return NS_ERROR_FAILURE;
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}
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// Set version to X509v3.
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*(aAttestCert->version.data) = SEC_CERTIFICATE_VERSION_3;
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aAttestCert->version.len = 1;
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SECItem innerDER = { siBuffer, nullptr, 0 };
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if (NS_WARN_IF(!SEC_ASN1EncodeItem(arena, &innerDER, aAttestCert.get(),
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SEC_ASN1_GET(CERT_CertificateTemplate)))) {
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return NS_ERROR_FAILURE;
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}
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SECItem* signedCert = PORT_ArenaZNew(arena, SECItem);
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if (NS_WARN_IF(!signedCert)) {
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return NS_ERROR_FAILURE;
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}
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srv = SEC_DerSignData(arena, signedCert, innerDER.data, innerDER.len,
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aAttestPrivKey.get(),
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SEC_OID_ANSIX962_ECDSA_SHA256_SIGNATURE);
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if (NS_WARN_IF(srv != SECSuccess)) {
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return NS_ERROR_FAILURE;
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}
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aAttestCert->derCert = *signedCert;
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MOZ_LOG(gNSSTokenLog, LogLevel::Debug,
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("U2F Soft Token attestation certificate generated."));
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return NS_OK;
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}
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// Set up the context for the soft U2F Token. This is called by NSS
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// initialization.
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nsresult
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U2FSoftTokenManager::Init()
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{
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// If we've already initialized, just return.
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if (mInitialized) {
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return NS_OK;
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}
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nsNSSShutDownPreventionLock locker;
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if (NS_WARN_IF(isAlreadyShutDown())) {
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return NS_ERROR_NOT_AVAILABLE;
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}
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UniquePK11SlotInfo slot(PK11_GetInternalKeySlot());
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MOZ_ASSERT(slot.get());
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// Search for an existing wrapping key, or create one.
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nsresult rv = GetOrCreateWrappingKey(slot, locker);
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if (NS_WARN_IF(NS_FAILED(rv))) {
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return rv;
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}
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mInitialized = true;
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MOZ_LOG(gNSSTokenLog, LogLevel::Debug, ("U2F Soft Token initialized."));
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return NS_OK;
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}
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// Convert a Private Key object into an opaque key handle, using AES Key Wrap
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// with the long-lived aPersistentKey mixed with aAppParam to convert aPrivKey.
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// The key handle's format is version || saltLen || salt || wrappedPrivateKey
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static UniqueSECItem
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KeyHandleFromPrivateKey(const UniquePK11SlotInfo& aSlot,
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const UniquePK11SymKey& aPersistentKey,
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uint8_t* aAppParam, uint32_t aAppParamLen,
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const UniqueSECKEYPrivateKey& aPrivKey,
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const nsNSSShutDownPreventionLock&)
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{
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MOZ_ASSERT(aSlot);
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MOZ_ASSERT(aPersistentKey);
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MOZ_ASSERT(aAppParam);
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MOZ_ASSERT(aPrivKey);
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if (NS_WARN_IF(!aSlot || !aPersistentKey || !aPrivKey || !aAppParam)) {
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return nullptr;
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}
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// Generate a random salt
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uint8_t saltParam[kSaltByteLen];
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SECStatus srv = PK11_GenerateRandomOnSlot(aSlot.get(), saltParam,
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sizeof(saltParam));
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if (NS_WARN_IF(srv != SECSuccess)) {
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MOZ_LOG(gNSSTokenLog, LogLevel::Warning,
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("Failed to generate a salt, NSS error #%d", PORT_GetError()));
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return nullptr;
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}
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// Prepare the HKDF (https://tools.ietf.org/html/rfc5869)
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CK_NSS_HKDFParams hkdfParams = { true, saltParam, sizeof(saltParam),
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true, aAppParam, aAppParamLen };
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SECItem kdfParams = { siBuffer, (unsigned char*)&hkdfParams,
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sizeof(hkdfParams) };
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// Derive a wrapping key from aPersistentKey, the salt, and the aAppParam.
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// CKM_AES_KEY_GEN and CKA_WRAP are key type and usage attributes of the
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// derived symmetric key and don't matter because we ignore them anyway.
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UniquePK11SymKey wrapKey(PK11_Derive(aPersistentKey.get(), CKM_NSS_HKDF_SHA256,
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&kdfParams, CKM_AES_KEY_GEN, CKA_WRAP,
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kWrappingKeyByteLen));
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if (NS_WARN_IF(!wrapKey.get())) {
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MOZ_LOG(gNSSTokenLog, LogLevel::Warning,
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("Failed to derive a wrapping key, NSS error #%d", PORT_GetError()));
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return nullptr;
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}
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UniqueSECItem wrappedKey(::SECITEM_AllocItem(/* default arena */ nullptr,
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/* no buffer */ nullptr,
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kWrappedKeyBufLen));
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if (NS_WARN_IF(!wrappedKey)) {
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MOZ_LOG(gNSSTokenLog, LogLevel::Warning, ("Failed to allocate memory"));
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return nullptr;
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}
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UniqueSECItem param(PK11_ParamFromIV(CKM_NSS_AES_KEY_WRAP_PAD,
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/* default IV */ nullptr ));
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srv = PK11_WrapPrivKey(aSlot.get(), wrapKey.get(), aPrivKey.get(),
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CKM_NSS_AES_KEY_WRAP_PAD, param.get(), wrappedKey.get(),
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/* wincx */ nullptr);
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if (NS_WARN_IF(srv != SECSuccess)) {
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MOZ_LOG(gNSSTokenLog, LogLevel::Warning,
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("Failed to wrap U2F key, NSS error #%d", PORT_GetError()));
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return nullptr;
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}
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// Concatenate the salt and the wrapped Private Key together
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mozilla::dom::CryptoBuffer keyHandleBuf;
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if (NS_WARN_IF(!keyHandleBuf.SetCapacity(wrappedKey.get()->len + sizeof(saltParam) + 2,
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mozilla::fallible))) {
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MOZ_LOG(gNSSTokenLog, LogLevel::Warning, ("Failed to allocate memory"));
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return nullptr;
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}
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|
|
// 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;
|
|
}
|
|
|
|
// Convert an opaque key handle aKeyHandle back into a Private Key object, using
|
|
// the long-lived aPersistentKey mixed with aAppParam and the AES Key Wrap
|
|
// algorithm.
|
|
static UniqueSECKEYPrivateKey
|
|
PrivateKeyFromKeyHandle(const UniquePK11SlotInfo& aSlot,
|
|
const UniquePK11SymKey& aPersistentKey,
|
|
uint8_t* aKeyHandle, uint32_t aKeyHandleLen,
|
|
uint8_t* aAppParam, uint32_t aAppParamLen,
|
|
const nsNSSShutDownPreventionLock&)
|
|
{
|
|
MOZ_ASSERT(aSlot);
|
|
MOZ_ASSERT(aPersistentKey);
|
|
MOZ_ASSERT(aKeyHandle);
|
|
MOZ_ASSERT(aAppParam);
|
|
MOZ_ASSERT(aAppParamLen == SHA256_LENGTH);
|
|
if (NS_WARN_IF(!aSlot || !aPersistentKey || !aKeyHandle || !aAppParam ||
|
|
aAppParamLen != SHA256_LENGTH)) {
|
|
return nullptr;
|
|
}
|
|
|
|
// As we only support one key format ourselves (right now), fail early if
|
|
// we aren't that length
|
|
if (NS_WARN_IF(aKeyHandleLen != kVersion1KeyHandleLen)) {
|
|
return nullptr;
|
|
}
|
|
|
|
if (NS_WARN_IF(aKeyHandle[0] != SoftTokenHandle::Version1)) {
|
|
// Unrecognized version
|
|
return nullptr;
|
|
}
|
|
|
|
uint8_t saltLen = aKeyHandle[1];
|
|
uint8_t* saltPtr = aKeyHandle + 2;
|
|
if (NS_WARN_IF(saltLen != kSaltByteLen)) {
|
|
return nullptr;
|
|
}
|
|
|
|
// Prepare the HKDF (https://tools.ietf.org/html/rfc5869)
|
|
CK_NSS_HKDFParams hkdfParams = { true, saltPtr, saltLen,
|
|
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;
|
|
}
|
|
|
|
uint8_t wrappedLen = aKeyHandleLen - saltLen - 2;
|
|
uint8_t* wrappedPtr = aKeyHandle + saltLen + 2;
|
|
|
|
ScopedAutoSECItem wrappedKeyItem(wrappedLen);
|
|
memcpy(wrappedKeyItem.data, wrappedPtr, wrappedKeyItem.len);
|
|
|
|
ScopedAutoSECItem pubKey(kPublicKeyLen);
|
|
|
|
UniqueSECItem param(PK11_ParamFromIV(CKM_NSS_AES_KEY_WRAP_PAD,
|
|
/* default IV */ nullptr ));
|
|
|
|
CK_ATTRIBUTE_TYPE usages[] = { CKA_SIGN };
|
|
int usageCount = 1;
|
|
|
|
UniqueSECKEYPrivateKey unwrappedKey(
|
|
PK11_UnwrapPrivKey(aSlot.get(), wrapKey.get(), CKM_NSS_AES_KEY_WRAP_PAD,
|
|
param.get(), &wrappedKeyItem,
|
|
/* no nickname */ nullptr,
|
|
/* discard pubkey */ &pubKey,
|
|
/* not permanent */ false,
|
|
/* non-exportable */ true,
|
|
CKK_EC, usages, usageCount,
|
|
/* wincx */ nullptr));
|
|
if (NS_WARN_IF(!unwrappedKey)) {
|
|
// Not our key.
|
|
MOZ_LOG(gNSSTokenLog, LogLevel::Debug,
|
|
("Could not unwrap key handle, NSS Error #%d", PORT_GetError()));
|
|
return nullptr;
|
|
}
|
|
|
|
return unwrappedKey;
|
|
}
|
|
|
|
// Return whether the provided version is supported by this token.
|
|
bool
|
|
U2FSoftTokenManager::IsCompatibleVersion(const nsAString& aVersion)
|
|
{
|
|
return mVersion == aVersion;
|
|
}
|
|
|
|
// IsRegistered determines if the provided key handle is usable by this token.
|
|
nsresult
|
|
U2FSoftTokenManager::IsRegistered(const nsTArray<uint8_t>& aKeyHandle,
|
|
const nsTArray<uint8_t>& aAppParam,
|
|
bool& aResult)
|
|
{
|
|
nsNSSShutDownPreventionLock locker;
|
|
if (NS_WARN_IF(isAlreadyShutDown())) {
|
|
return NS_ERROR_FAILURE;
|
|
}
|
|
|
|
if (!mInitialized) {
|
|
nsresult rv = Init();
|
|
if (NS_WARN_IF(NS_FAILED(rv))) {
|
|
return rv;
|
|
}
|
|
}
|
|
|
|
UniquePK11SlotInfo slot(PK11_GetInternalSlot());
|
|
MOZ_ASSERT(slot.get());
|
|
|
|
// Decode the key handle
|
|
UniqueSECKEYPrivateKey privKey = PrivateKeyFromKeyHandle(slot, mWrappingKey,
|
|
const_cast<uint8_t*>(aKeyHandle.Elements()),
|
|
aKeyHandle.Length(),
|
|
const_cast<uint8_t*>(aAppParam.Elements()),
|
|
aAppParam.Length(),
|
|
locker);
|
|
aResult = privKey.get() != nullptr;
|
|
return NS_OK;
|
|
}
|
|
|
|
// A U2F Register operation causes a new key pair to be generated by the token.
|
|
// The token then returns the public key of the key pair, and a handle to the
|
|
// private key, which is a fancy way of saying "key wrapped private key", as
|
|
// well as the generated attestation certificate and a signature using that
|
|
// certificate's private key.
|
|
//
|
|
// The KeyHandleFromPrivateKey and PrivateKeyFromKeyHandle methods perform
|
|
// the actual key wrap/unwrap operations.
|
|
//
|
|
// The format of the return registration data is as follows:
|
|
//
|
|
// Bytes Value
|
|
// 1 0x05
|
|
// 65 public key
|
|
// 1 key handle length
|
|
// * key handle
|
|
// ASN.1 attestation certificate
|
|
// * attestation signature
|
|
//
|
|
RefPtr<U2FRegisterPromise>
|
|
U2FSoftTokenManager::Register(const nsTArray<WebAuthnScopedCredentialDescriptor>& aDescriptors,
|
|
const nsTArray<uint8_t>& aApplication,
|
|
const nsTArray<uint8_t>& aChallenge,
|
|
uint32_t aTimeoutMS)
|
|
{
|
|
nsNSSShutDownPreventionLock locker;
|
|
if (NS_WARN_IF(isAlreadyShutDown())) {
|
|
return U2FRegisterPromise::CreateAndReject(NS_ERROR_NOT_AVAILABLE, __func__);
|
|
}
|
|
|
|
if (!mInitialized) {
|
|
nsresult rv = Init();
|
|
if (NS_WARN_IF(NS_FAILED(rv))) {
|
|
return U2FRegisterPromise::CreateAndReject(rv, __func__);
|
|
}
|
|
}
|
|
|
|
// Optional exclusion list.
|
|
for (auto desc: aDescriptors) {
|
|
bool isRegistered = false;
|
|
nsresult rv = IsRegistered(desc.id(), aApplication, isRegistered);
|
|
if (NS_FAILED(rv)) {
|
|
return U2FRegisterPromise::CreateAndReject(rv, __func__);
|
|
}
|
|
if (isRegistered) {
|
|
return U2FRegisterPromise::CreateAndReject(NS_ERROR_DOM_NOT_ALLOWED_ERR, __func__);
|
|
}
|
|
}
|
|
|
|
// We should already have a wrapping key
|
|
MOZ_ASSERT(mWrappingKey);
|
|
|
|
UniquePK11SlotInfo slot(PK11_GetInternalSlot());
|
|
MOZ_ASSERT(slot.get());
|
|
|
|
// Construct a one-time-use Attestation Certificate
|
|
UniqueSECKEYPrivateKey attestPrivKey;
|
|
UniqueCERTCertificate attestCert;
|
|
nsresult rv = GetAttestationCertificate(slot, attestPrivKey, attestCert,
|
|
locker);
|
|
if (NS_WARN_IF(NS_FAILED(rv))) {
|
|
return U2FRegisterPromise::CreateAndReject(NS_ERROR_FAILURE, __func__);
|
|
}
|
|
MOZ_ASSERT(attestCert);
|
|
MOZ_ASSERT(attestPrivKey);
|
|
|
|
// Generate a new keypair; the private will be wrapped into a Key Handle
|
|
UniqueSECKEYPrivateKey privKey;
|
|
UniqueSECKEYPublicKey pubKey;
|
|
rv = GenEcKeypair(slot, privKey, pubKey, locker);
|
|
if (NS_WARN_IF(NS_FAILED(rv))) {
|
|
return U2FRegisterPromise::CreateAndReject(NS_ERROR_FAILURE, __func__);
|
|
}
|
|
|
|
// The key handle will be the result of keywrap(privKey, key=mWrappingKey)
|
|
UniqueSECItem keyHandleItem = KeyHandleFromPrivateKey(slot, mWrappingKey,
|
|
const_cast<uint8_t*>(aApplication.Elements()),
|
|
aApplication.Length(),
|
|
privKey, locker);
|
|
if (NS_WARN_IF(!keyHandleItem.get())) {
|
|
return U2FRegisterPromise::CreateAndReject(NS_ERROR_FAILURE, __func__);
|
|
}
|
|
|
|
// Sign the challenge using the Attestation privkey (from attestCert)
|
|
mozilla::dom::CryptoBuffer signedDataBuf;
|
|
if (NS_WARN_IF(!signedDataBuf.SetCapacity(1 + aApplication.Length() + aChallenge.Length() +
|
|
keyHandleItem->len + kPublicKeyLen,
|
|
mozilla::fallible))) {
|
|
return U2FRegisterPromise::CreateAndReject(NS_ERROR_OUT_OF_MEMORY, __func__);
|
|
}
|
|
|
|
// // It's OK to ignore the return values here because we're writing into
|
|
// // pre-allocated space
|
|
signedDataBuf.AppendElement(0x00, mozilla::fallible);
|
|
signedDataBuf.AppendElements(aApplication, mozilla::fallible);
|
|
signedDataBuf.AppendElements(aChallenge, mozilla::fallible);
|
|
signedDataBuf.AppendSECItem(keyHandleItem.get());
|
|
signedDataBuf.AppendSECItem(pubKey->u.ec.publicValue);
|
|
|
|
ScopedAutoSECItem signatureItem;
|
|
SECStatus srv = SEC_SignData(&signatureItem, signedDataBuf.Elements(),
|
|
signedDataBuf.Length(), attestPrivKey.get(),
|
|
SEC_OID_ANSIX962_ECDSA_SHA256_SIGNATURE);
|
|
if (NS_WARN_IF(srv != SECSuccess)) {
|
|
MOZ_LOG(gNSSTokenLog, LogLevel::Warning,
|
|
("Signature failure: %d", PORT_GetError()));
|
|
return U2FRegisterPromise::CreateAndReject(NS_ERROR_FAILURE, __func__);
|
|
}
|
|
|
|
// Serialize the registration data
|
|
mozilla::dom::CryptoBuffer registrationBuf;
|
|
if (NS_WARN_IF(!registrationBuf.SetCapacity(1 + kPublicKeyLen + 1 + keyHandleItem->len +
|
|
attestCert.get()->derCert.len +
|
|
signatureItem.len, mozilla::fallible))) {
|
|
return U2FRegisterPromise::CreateAndReject(NS_ERROR_OUT_OF_MEMORY, __func__);
|
|
}
|
|
registrationBuf.AppendElement(0x05, mozilla::fallible);
|
|
registrationBuf.AppendSECItem(pubKey->u.ec.publicValue);
|
|
registrationBuf.AppendElement(keyHandleItem->len, mozilla::fallible);
|
|
registrationBuf.AppendSECItem(keyHandleItem.get());
|
|
registrationBuf.AppendSECItem(attestCert.get()->derCert);
|
|
registrationBuf.AppendSECItem(signatureItem);
|
|
|
|
U2FRegisterResult result((nsTArray<uint8_t>(registrationBuf)));
|
|
return U2FRegisterPromise::CreateAndResolve(Move(result), __func__);
|
|
}
|
|
|
|
// A U2F Sign operation creates a signature over the "param" arguments (plus
|
|
// some other stuff) using the private key indicated in the key handle argument.
|
|
//
|
|
// The format of the signed data is as follows:
|
|
//
|
|
// 32 Application parameter
|
|
// 1 User presence (0x01)
|
|
// 4 Counter
|
|
// 32 Challenge parameter
|
|
//
|
|
// The format of the signature data is as follows:
|
|
//
|
|
// 1 User presence
|
|
// 4 Counter
|
|
// * Signature
|
|
//
|
|
RefPtr<U2FSignPromise>
|
|
U2FSoftTokenManager::Sign(const nsTArray<WebAuthnScopedCredentialDescriptor>& aDescriptors,
|
|
const nsTArray<uint8_t>& aApplication,
|
|
const nsTArray<uint8_t>& aChallenge,
|
|
uint32_t aTimeoutMS)
|
|
{
|
|
nsNSSShutDownPreventionLock locker;
|
|
if (NS_WARN_IF(isAlreadyShutDown())) {
|
|
return U2FSignPromise::CreateAndReject(NS_ERROR_NOT_AVAILABLE, __func__);
|
|
}
|
|
|
|
nsTArray<uint8_t> keyHandle;
|
|
for (auto desc: aDescriptors) {
|
|
bool isRegistered = false;
|
|
nsresult rv = IsRegistered(desc.id(), aApplication, isRegistered);
|
|
if (NS_SUCCEEDED(rv) && isRegistered) {
|
|
keyHandle.Assign(desc.id());
|
|
break;
|
|
}
|
|
}
|
|
|
|
// Fail if we didn't recognize a key id.
|
|
if (keyHandle.IsEmpty()) {
|
|
return U2FSignPromise::CreateAndReject(NS_ERROR_DOM_NOT_ALLOWED_ERR, __func__);
|
|
}
|
|
|
|
MOZ_ASSERT(mWrappingKey);
|
|
|
|
UniquePK11SlotInfo slot(PK11_GetInternalSlot());
|
|
MOZ_ASSERT(slot.get());
|
|
|
|
if (NS_WARN_IF((aChallenge.Length() != kParamLen) || (aApplication.Length() != kParamLen))) {
|
|
MOZ_LOG(gNSSTokenLog, LogLevel::Warning,
|
|
("Parameter lengths are wrong! challenge=%d app=%d expected=%d",
|
|
(uint32_t)aChallenge.Length(), (uint32_t)aApplication.Length(), kParamLen));
|
|
|
|
return U2FSignPromise::CreateAndReject(NS_ERROR_ILLEGAL_VALUE, __func__);
|
|
}
|
|
|
|
// Decode the key handle
|
|
UniqueSECKEYPrivateKey privKey = PrivateKeyFromKeyHandle(slot, mWrappingKey,
|
|
const_cast<uint8_t*>(keyHandle.Elements()),
|
|
keyHandle.Length(),
|
|
const_cast<uint8_t*>(aApplication.Elements()),
|
|
aApplication.Length(),
|
|
locker);
|
|
if (NS_WARN_IF(!privKey.get())) {
|
|
MOZ_LOG(gNSSTokenLog, LogLevel::Warning, ("Couldn't get the priv key!"));
|
|
return U2FSignPromise::CreateAndReject(NS_ERROR_FAILURE, __func__);
|
|
}
|
|
|
|
// Increment the counter and turn it into a SECItem
|
|
mCounter += 1;
|
|
ScopedAutoSECItem counterItem(4);
|
|
counterItem.data[0] = (mCounter >> 24) & 0xFF;
|
|
counterItem.data[1] = (mCounter >> 16) & 0xFF;
|
|
counterItem.data[2] = (mCounter >> 8) & 0xFF;
|
|
counterItem.data[3] = (mCounter >> 0) & 0xFF;
|
|
uint32_t counter = mCounter;
|
|
GetMainThreadEventTarget()->Dispatch(NS_NewRunnableFunction(
|
|
"dom::U2FSoftTokenManager::Sign",
|
|
[counter] () {
|
|
MOZ_ASSERT(NS_IsMainThread());
|
|
Preferences::SetUint(PREF_U2F_NSSTOKEN_COUNTER, counter);
|
|
}));
|
|
|
|
// Compute the signature
|
|
mozilla::dom::CryptoBuffer signedDataBuf;
|
|
if (NS_WARN_IF(!signedDataBuf.SetCapacity(1 + 4 + (2 * kParamLen), mozilla::fallible))) {
|
|
return U2FSignPromise::CreateAndReject(NS_ERROR_OUT_OF_MEMORY, __func__);
|
|
}
|
|
|
|
// It's OK to ignore the return values here because we're writing into
|
|
// pre-allocated space
|
|
signedDataBuf.AppendElements(aApplication.Elements(), aApplication.Length(),
|
|
mozilla::fallible);
|
|
signedDataBuf.AppendElement(0x01, mozilla::fallible);
|
|
signedDataBuf.AppendSECItem(counterItem);
|
|
signedDataBuf.AppendElements(aChallenge.Elements(), aChallenge.Length(),
|
|
mozilla::fallible);
|
|
|
|
if (MOZ_LOG_TEST(gNSSTokenLog, LogLevel::Debug)) {
|
|
nsAutoCString base64;
|
|
nsresult rv = Base64URLEncode(signedDataBuf.Length(), signedDataBuf.Elements(),
|
|
Base64URLEncodePaddingPolicy::Omit, base64);
|
|
if (NS_WARN_IF(NS_FAILED(rv))) {
|
|
return U2FSignPromise::CreateAndReject(NS_ERROR_FAILURE, __func__);
|
|
}
|
|
|
|
MOZ_LOG(gNSSTokenLog, LogLevel::Debug,
|
|
("U2F Token signing bytes (base64): %s", base64.get()));
|
|
}
|
|
|
|
ScopedAutoSECItem signatureItem;
|
|
SECStatus srv = SEC_SignData(&signatureItem, signedDataBuf.Elements(),
|
|
signedDataBuf.Length(), privKey.get(),
|
|
SEC_OID_ANSIX962_ECDSA_SHA256_SIGNATURE);
|
|
if (NS_WARN_IF(srv != SECSuccess)) {
|
|
MOZ_LOG(gNSSTokenLog, LogLevel::Warning,
|
|
("Signature failure: %d", PORT_GetError()));
|
|
return U2FSignPromise::CreateAndReject(NS_ERROR_FAILURE, __func__);
|
|
}
|
|
|
|
// Assemble the signature data into a buffer for return
|
|
mozilla::dom::CryptoBuffer signatureBuf;
|
|
if (NS_WARN_IF(!signatureBuf.SetCapacity(1 + counterItem.len + signatureItem.len,
|
|
mozilla::fallible))) {
|
|
return U2FSignPromise::CreateAndReject(NS_ERROR_OUT_OF_MEMORY, __func__);
|
|
}
|
|
|
|
// It's OK to ignore the return values here because we're writing into
|
|
// pre-allocated space
|
|
signatureBuf.AppendElement(0x01, mozilla::fallible);
|
|
signatureBuf.AppendSECItem(counterItem);
|
|
signatureBuf.AppendSECItem(signatureItem);
|
|
|
|
U2FSignResult result(Move(keyHandle), nsTArray<uint8_t>(signatureBuf));
|
|
return U2FSignPromise::CreateAndResolve(Move(result), __func__);
|
|
}
|
|
|
|
void
|
|
U2FSoftTokenManager::Cancel()
|
|
{
|
|
// This implementation is sync, requests can't be aborted.
|
|
}
|
|
|
|
}
|
|
}
|