зеркало из https://github.com/mozilla/gecko-dev.git
494 строки
17 KiB
C++
494 строки
17 KiB
C++
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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/* vim: set ts=8 sts=2 et sw=2 tw=80: */
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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
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* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
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#include "SRICheck.h"
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#include "mozilla/Base64.h"
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#include "mozilla/LoadTainting.h"
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#include "mozilla/Logging.h"
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#include "mozilla/Preferences.h"
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#include "mozilla/dom/SRILogHelper.h"
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#include "mozilla/dom/SRIMetadata.h"
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#include "nsComponentManagerUtils.h"
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#include "nsContentUtils.h"
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#include "nsIChannel.h"
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#include "nsIConsoleReportCollector.h"
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#include "nsIScriptError.h"
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#include "nsIURI.h"
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#include "nsNetUtil.h"
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#include "nsWhitespaceTokenizer.h"
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#define SRIVERBOSE(args) \
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MOZ_LOG(SRILogHelper::GetSriLog(), mozilla::LogLevel::Verbose, args)
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#define SRILOG(args) \
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MOZ_LOG(SRILogHelper::GetSriLog(), mozilla::LogLevel::Debug, args)
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#define SRIERROR(args) \
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MOZ_LOG(SRILogHelper::GetSriLog(), mozilla::LogLevel::Error, args)
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namespace mozilla::dom {
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/**
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* Returns whether or not the sub-resource about to be loaded is eligible
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* for integrity checks. If it's not, the checks will be skipped and the
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* sub-resource will be loaded.
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*/
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static nsresult IsEligible(nsIChannel* aChannel,
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mozilla::LoadTainting aTainting,
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const nsACString& aSourceFileURI,
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nsIConsoleReportCollector* aReporter) {
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NS_ENSURE_ARG_POINTER(aReporter);
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if (!aChannel) {
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SRILOG(("SRICheck::IsEligible, null channel"));
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return NS_ERROR_SRI_NOT_ELIGIBLE;
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}
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// Was the sub-resource loaded via CORS?
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if (aTainting == LoadTainting::CORS) {
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SRILOG(("SRICheck::IsEligible, CORS mode"));
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return NS_OK;
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}
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nsCOMPtr<nsIURI> finalURI;
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nsresult rv = NS_GetFinalChannelURI(aChannel, getter_AddRefs(finalURI));
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NS_ENSURE_SUCCESS(rv, rv);
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nsCOMPtr<nsIURI> originalURI;
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rv = aChannel->GetOriginalURI(getter_AddRefs(originalURI));
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NS_ENSURE_SUCCESS(rv, rv);
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nsAutoCString requestSpec;
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rv = originalURI->GetSpec(requestSpec);
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NS_ENSURE_SUCCESS(rv, rv);
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if (MOZ_LOG_TEST(SRILogHelper::GetSriLog(), mozilla::LogLevel::Debug)) {
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SRILOG(("SRICheck::IsEligible, requestURI=%s; finalURI=%s",
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requestSpec.get(),
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finalURI ? finalURI->GetSpecOrDefault().get() : ""));
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}
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// Is the sub-resource same-origin?
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if (aTainting == LoadTainting::Basic) {
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SRILOG(("SRICheck::IsEligible, same-origin"));
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return NS_OK;
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}
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SRILOG(("SRICheck::IsEligible, NOT same-origin"));
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NS_ConvertUTF8toUTF16 requestSpecUTF16(requestSpec);
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nsTArray<nsString> params;
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params.AppendElement(requestSpecUTF16);
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aReporter->AddConsoleReport(
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nsIScriptError::errorFlag, "Sub-resource Integrity"_ns,
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nsContentUtils::eSECURITY_PROPERTIES, aSourceFileURI, 0, 0,
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"IneligibleResource"_ns, const_cast<const nsTArray<nsString>&>(params));
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return NS_ERROR_SRI_NOT_ELIGIBLE;
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}
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/* static */
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nsresult SRICheck::IntegrityMetadata(const nsAString& aMetadataList,
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const nsACString& aSourceFileURI,
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nsIConsoleReportCollector* aReporter,
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SRIMetadata* outMetadata) {
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NS_ENSURE_ARG_POINTER(outMetadata);
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NS_ENSURE_ARG_POINTER(aReporter);
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MOZ_ASSERT(outMetadata->IsEmpty()); // caller must pass empty metadata
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// put a reasonable bound on the length of the metadata
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NS_ConvertUTF16toUTF8 metadataList(aMetadataList);
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if (metadataList.Length() > SRICheck::MAX_METADATA_LENGTH) {
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metadataList.Truncate(SRICheck::MAX_METADATA_LENGTH);
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}
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SRILOG(("SRICheck::IntegrityMetadata, metadataList=%s", metadataList.get()));
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// the integrity attribute is a list of whitespace-separated hashes
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// and options so we need to look at them one by one and pick the
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// strongest (valid) one
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nsCWhitespaceTokenizer tokenizer(metadataList);
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nsAutoCString token;
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for (uint32_t i = 0;
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tokenizer.hasMoreTokens() && i < SRICheck::MAX_METADATA_TOKENS; ++i) {
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token = tokenizer.nextToken();
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SRIMetadata metadata(token);
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if (metadata.IsMalformed()) {
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NS_ConvertUTF8toUTF16 tokenUTF16(token);
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nsTArray<nsString> params;
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params.AppendElement(tokenUTF16);
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aReporter->AddConsoleReport(
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nsIScriptError::warningFlag, "Sub-resource Integrity"_ns,
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nsContentUtils::eSECURITY_PROPERTIES, aSourceFileURI, 0, 0,
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"MalformedIntegrityHash"_ns,
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const_cast<const nsTArray<nsString>&>(params));
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} else if (!metadata.IsAlgorithmSupported()) {
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nsAutoCString alg;
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metadata.GetAlgorithm(&alg);
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NS_ConvertUTF8toUTF16 algUTF16(alg);
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nsTArray<nsString> params;
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params.AppendElement(algUTF16);
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aReporter->AddConsoleReport(
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nsIScriptError::warningFlag, "Sub-resource Integrity"_ns,
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nsContentUtils::eSECURITY_PROPERTIES, aSourceFileURI, 0, 0,
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"UnsupportedHashAlg"_ns,
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const_cast<const nsTArray<nsString>&>(params));
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}
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nsAutoCString alg1, alg2;
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if (MOZ_LOG_TEST(SRILogHelper::GetSriLog(), mozilla::LogLevel::Debug)) {
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outMetadata->GetAlgorithm(&alg1);
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metadata.GetAlgorithm(&alg2);
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}
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if (*outMetadata == metadata) {
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SRILOG(("SRICheck::IntegrityMetadata, alg '%s' is the same as '%s'",
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alg1.get(), alg2.get()));
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*outMetadata += metadata; // add new hash to strongest metadata
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} else if (*outMetadata < metadata) {
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SRILOG(("SRICheck::IntegrityMetadata, alg '%s' is weaker than '%s'",
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alg1.get(), alg2.get()));
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*outMetadata = metadata; // replace strongest metadata with current
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}
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}
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outMetadata->mIntegrityString = aMetadataList;
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if (MOZ_LOG_TEST(SRILogHelper::GetSriLog(), mozilla::LogLevel::Debug)) {
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if (outMetadata->IsValid()) {
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nsAutoCString alg;
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outMetadata->GetAlgorithm(&alg);
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SRILOG(("SRICheck::IntegrityMetadata, using a '%s' hash", alg.get()));
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} else if (outMetadata->IsEmpty()) {
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SRILOG(("SRICheck::IntegrityMetadata, no metadata"));
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} else {
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SRILOG(("SRICheck::IntegrityMetadata, no valid metadata found"));
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}
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}
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return NS_OK;
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}
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//////////////////////////////////////////////////////////////
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//
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//////////////////////////////////////////////////////////////
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SRICheckDataVerifier::SRICheckDataVerifier(const SRIMetadata& aMetadata,
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const nsACString& aSourceFileURI,
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nsIConsoleReportCollector* aReporter)
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: mCryptoHash(nullptr),
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mBytesHashed(0),
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mHashLength(0),
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mHashType('\0'),
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mInvalidMetadata(false),
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mComplete(false) {
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MOZ_ASSERT(!aMetadata.IsEmpty()); // should be checked by caller
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MOZ_ASSERT(aReporter);
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if (!aMetadata.IsValid()) {
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nsTArray<nsString> params;
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aReporter->AddConsoleReport(
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nsIScriptError::warningFlag, "Sub-resource Integrity"_ns,
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nsContentUtils::eSECURITY_PROPERTIES, aSourceFileURI, 0, 0,
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"NoValidMetadata"_ns, const_cast<const nsTArray<nsString>&>(params));
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mInvalidMetadata = true;
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return; // ignore invalid metadata for forward-compatibility
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}
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aMetadata.GetHashType(&mHashType, &mHashLength);
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}
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nsresult SRICheckDataVerifier::EnsureCryptoHash() {
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MOZ_ASSERT(!mInvalidMetadata);
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if (mCryptoHash) {
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return NS_OK;
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}
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nsresult rv;
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nsCOMPtr<nsICryptoHash> cryptoHash =
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do_CreateInstance("@mozilla.org/security/hash;1", &rv);
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NS_ENSURE_SUCCESS(rv, rv);
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rv = cryptoHash->Init(mHashType);
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NS_ENSURE_SUCCESS(rv, rv);
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mCryptoHash = cryptoHash;
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return NS_OK;
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}
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nsresult SRICheckDataVerifier::Update(uint32_t aStringLen,
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const uint8_t* aString) {
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NS_ENSURE_ARG_POINTER(aString);
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if (mInvalidMetadata) {
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return NS_OK; // ignoring any data updates, see mInvalidMetadata usage
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}
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nsresult rv;
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rv = EnsureCryptoHash();
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NS_ENSURE_SUCCESS(rv, rv);
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mBytesHashed += aStringLen;
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return mCryptoHash->Update(aString, aStringLen);
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}
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nsresult SRICheckDataVerifier::Finish() {
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if (mInvalidMetadata || mComplete) {
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return NS_OK; // already finished or invalid metadata
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}
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nsresult rv;
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rv = EnsureCryptoHash(); // we need computed hash even for 0-length data
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NS_ENSURE_SUCCESS(rv, rv);
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rv = mCryptoHash->Finish(false, mComputedHash);
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mCryptoHash = nullptr;
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mComplete = true;
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return rv;
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}
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nsresult SRICheckDataVerifier::VerifyHash(
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const SRIMetadata& aMetadata, uint32_t aHashIndex,
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const nsACString& aSourceFileURI, nsIConsoleReportCollector* aReporter) {
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NS_ENSURE_ARG_POINTER(aReporter);
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nsAutoCString base64Hash;
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aMetadata.GetHash(aHashIndex, &base64Hash);
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SRILOG(("SRICheckDataVerifier::VerifyHash, hash[%u]=%s", aHashIndex,
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base64Hash.get()));
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nsAutoCString binaryHash;
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if (NS_WARN_IF(NS_FAILED(Base64Decode(base64Hash, binaryHash)))) {
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nsTArray<nsString> params;
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aReporter->AddConsoleReport(
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nsIScriptError::errorFlag, "Sub-resource Integrity"_ns,
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nsContentUtils::eSECURITY_PROPERTIES, aSourceFileURI, 0, 0,
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"InvalidIntegrityBase64"_ns,
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const_cast<const nsTArray<nsString>&>(params));
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return NS_ERROR_SRI_CORRUPT;
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}
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uint32_t hashLength;
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int8_t hashType;
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aMetadata.GetHashType(&hashType, &hashLength);
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if (binaryHash.Length() != hashLength) {
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nsTArray<nsString> params;
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aReporter->AddConsoleReport(
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nsIScriptError::errorFlag, "Sub-resource Integrity"_ns,
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nsContentUtils::eSECURITY_PROPERTIES, aSourceFileURI, 0, 0,
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"InvalidIntegrityLength"_ns,
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const_cast<const nsTArray<nsString>&>(params));
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return NS_ERROR_SRI_CORRUPT;
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}
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if (MOZ_LOG_TEST(SRILogHelper::GetSriLog(), mozilla::LogLevel::Debug)) {
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nsAutoCString encodedHash;
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nsresult rv = Base64Encode(mComputedHash, encodedHash);
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if (NS_SUCCEEDED(rv)) {
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SRILOG(("SRICheckDataVerifier::VerifyHash, mComputedHash=%s",
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encodedHash.get()));
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}
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}
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if (!binaryHash.Equals(mComputedHash)) {
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SRILOG(("SRICheckDataVerifier::VerifyHash, hash[%u] did not match",
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aHashIndex));
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return NS_ERROR_SRI_CORRUPT;
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}
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SRILOG(("SRICheckDataVerifier::VerifyHash, hash[%u] verified successfully",
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aHashIndex));
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return NS_OK;
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}
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nsresult SRICheckDataVerifier::Verify(const SRIMetadata& aMetadata,
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nsIChannel* aChannel,
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const nsACString& aSourceFileURI,
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nsIConsoleReportCollector* aReporter) {
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NS_ENSURE_ARG_POINTER(aReporter);
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if (MOZ_LOG_TEST(SRILogHelper::GetSriLog(), mozilla::LogLevel::Debug)) {
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nsAutoCString requestURL;
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nsCOMPtr<nsIRequest> request = aChannel;
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request->GetName(requestURL);
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SRILOG(("SRICheckDataVerifier::Verify, url=%s (length=%zu)",
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requestURL.get(), mBytesHashed));
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}
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nsresult rv = Finish();
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NS_ENSURE_SUCCESS(rv, rv);
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nsCOMPtr<nsILoadInfo> loadInfo = aChannel->LoadInfo();
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LoadTainting tainting = loadInfo->GetTainting();
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if (NS_FAILED(IsEligible(aChannel, tainting, aSourceFileURI, aReporter))) {
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return NS_ERROR_SRI_NOT_ELIGIBLE;
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}
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if (mInvalidMetadata) {
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return NS_OK; // ignore invalid metadata for forward-compatibility
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}
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for (uint32_t i = 0; i < aMetadata.HashCount(); i++) {
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if (NS_SUCCEEDED(VerifyHash(aMetadata, i, aSourceFileURI, aReporter))) {
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return NS_OK; // stop at the first valid hash
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}
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}
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nsAutoCString alg;
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aMetadata.GetAlgorithm(&alg);
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NS_ConvertUTF8toUTF16 algUTF16(alg);
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nsTArray<nsString> params;
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params.AppendElement(algUTF16);
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aReporter->AddConsoleReport(
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nsIScriptError::errorFlag, "Sub-resource Integrity"_ns,
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nsContentUtils::eSECURITY_PROPERTIES, aSourceFileURI, 0, 0,
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"IntegrityMismatch"_ns, const_cast<const nsTArray<nsString>&>(params));
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return NS_ERROR_SRI_CORRUPT;
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}
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uint32_t SRICheckDataVerifier::DataSummaryLength() {
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MOZ_ASSERT(!mInvalidMetadata);
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return sizeof(mHashType) + sizeof(mHashLength) + mHashLength;
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}
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uint32_t SRICheckDataVerifier::EmptyDataSummaryLength() {
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return sizeof(int8_t) + sizeof(uint32_t);
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}
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nsresult SRICheckDataVerifier::DataSummaryLength(uint32_t aDataLen,
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const uint8_t* aData,
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uint32_t* length) {
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*length = 0;
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NS_ENSURE_ARG_POINTER(aData);
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// we expect to always encode an SRI, even if it is empty or incomplete
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if (aDataLen < EmptyDataSummaryLength()) {
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SRILOG(
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("SRICheckDataVerifier::DataSummaryLength, encoded length[%u] is too "
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"small",
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aDataLen));
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return NS_ERROR_SRI_IMPORT;
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}
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// decode the content of the buffer
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size_t offset = sizeof(mHashType);
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decltype(mHashLength) len = 0;
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memcpy(&len, &aData[offset], sizeof(mHashLength));
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offset += sizeof(mHashLength);
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SRIVERBOSE(
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("SRICheckDataVerifier::DataSummaryLength, header {%x, %x, %x, %x, %x, "
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"...}",
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aData[0], aData[1], aData[2], aData[3], aData[4]));
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if (offset + len > aDataLen) {
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SRILOG(
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("SRICheckDataVerifier::DataSummaryLength, encoded length[%u] overflow "
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"the buffer size",
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aDataLen));
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SRIVERBOSE(("SRICheckDataVerifier::DataSummaryLength, offset[%u], len[%u]",
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uint32_t(offset), uint32_t(len)));
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return NS_ERROR_SRI_IMPORT;
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}
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*length = uint32_t(offset + len);
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return NS_OK;
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}
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nsresult SRICheckDataVerifier::ImportDataSummary(uint32_t aDataLen,
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const uint8_t* aData) {
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MOZ_ASSERT(!mInvalidMetadata); // mHashType and mHashLength should be valid
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MOZ_ASSERT(!mCryptoHash); // EnsureCryptoHash should not have been called
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NS_ENSURE_ARG_POINTER(aData);
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if (mInvalidMetadata) {
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return NS_OK; // ignoring any data updates, see mInvalidMetadata usage
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}
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// we expect to always encode an SRI, even if it is empty or incomplete
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if (aDataLen < DataSummaryLength()) {
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SRILOG(
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("SRICheckDataVerifier::ImportDataSummary, encoded length[%u] is too "
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"small",
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aDataLen));
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return NS_ERROR_SRI_IMPORT;
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}
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SRIVERBOSE(
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("SRICheckDataVerifier::ImportDataSummary, header {%x, %x, %x, %x, %x, "
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"...}",
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aData[0], aData[1], aData[2], aData[3], aData[4]));
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// decode the content of the buffer
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size_t offset = 0;
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decltype(mHashType) hashType;
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memcpy(&hashType, &aData[offset], sizeof(mHashType));
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if (hashType != mHashType) {
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SRILOG(
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("SRICheckDataVerifier::ImportDataSummary, hash type[%d] does not "
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"match[%d]",
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hashType, mHashType));
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return NS_ERROR_SRI_UNEXPECTED_HASH_TYPE;
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}
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offset += sizeof(mHashType);
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decltype(mHashLength) hashLength;
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memcpy(&hashLength, &aData[offset], sizeof(mHashLength));
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if (hashLength != mHashLength) {
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SRILOG(
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("SRICheckDataVerifier::ImportDataSummary, hash length[%d] does not "
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"match[%d]",
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hashLength, mHashLength));
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return NS_ERROR_SRI_UNEXPECTED_HASH_TYPE;
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}
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offset += sizeof(mHashLength);
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// copy the hash to mComputedHash, as-if we had finished streaming the bytes
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mComputedHash.Assign(reinterpret_cast<const char*>(&aData[offset]),
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mHashLength);
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mCryptoHash = nullptr;
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mComplete = true;
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return NS_OK;
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}
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nsresult SRICheckDataVerifier::ExportDataSummary(uint32_t aDataLen,
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uint8_t* aData) {
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MOZ_ASSERT(!mInvalidMetadata); // mHashType and mHashLength should be valid
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MOZ_ASSERT(mComplete); // finished streaming
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NS_ENSURE_ARG_POINTER(aData);
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NS_ENSURE_TRUE(aDataLen >= DataSummaryLength(), NS_ERROR_INVALID_ARG);
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// serialize the hash in the buffer
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size_t offset = 0;
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memcpy(&aData[offset], &mHashType, sizeof(mHashType));
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offset += sizeof(mHashType);
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memcpy(&aData[offset], &mHashLength, sizeof(mHashLength));
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offset += sizeof(mHashLength);
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|
|
|
SRIVERBOSE(
|
|
("SRICheckDataVerifier::ExportDataSummary, header {%x, %x, %x, %x, %x, "
|
|
"...}",
|
|
aData[0], aData[1], aData[2], aData[3], aData[4]));
|
|
|
|
// copy the hash to mComputedHash, as-if we had finished streaming the bytes
|
|
nsCharTraits<char>::copy(reinterpret_cast<char*>(&aData[offset]),
|
|
mComputedHash.get(), mHashLength);
|
|
return NS_OK;
|
|
}
|
|
|
|
nsresult SRICheckDataVerifier::ExportEmptyDataSummary(uint32_t aDataLen,
|
|
uint8_t* aData) {
|
|
NS_ENSURE_ARG_POINTER(aData);
|
|
NS_ENSURE_TRUE(aDataLen >= EmptyDataSummaryLength(), NS_ERROR_INVALID_ARG);
|
|
|
|
// serialize an unknown hash in the buffer, to be able to skip it later
|
|
size_t offset = 0;
|
|
memset(&aData[offset], 0, sizeof(mHashType));
|
|
offset += sizeof(mHashType);
|
|
memset(&aData[offset], 0, sizeof(mHashLength));
|
|
offset += sizeof(mHashLength);
|
|
|
|
SRIVERBOSE(
|
|
("SRICheckDataVerifier::ExportEmptyDataSummary, header {%x, %x, %x, %x, "
|
|
"%x, ...}",
|
|
aData[0], aData[1], aData[2], aData[3], aData[4]));
|
|
|
|
return NS_OK;
|
|
}
|
|
|
|
} // namespace mozilla::dom
|