123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137 |
- // Copyright 2013 The Chromium Authors. All rights reserved.
- // Use of this source code is governed by a BSD-style license that can be
- // found in the LICENSE file.
- #include "components/nacl/loader/nacl_validation_query.h"
- #include <stdint.h>
- #include <string.h>
- #include "base/check.h"
- #include "components/nacl/loader/nacl_validation_db.h"
- #include "crypto/nss_util.h"
- #include "native_client/src/public/validation_cache.h"
- NaClValidationQueryContext::NaClValidationQueryContext(
- NaClValidationDB* db,
- const std::string& profile_key,
- const std::string& nacl_version)
- : db_(db),
- profile_key_(profile_key),
- nacl_version_(nacl_version) {
- // Sanity checks.
- CHECK(profile_key.length() >= 8);
- CHECK(nacl_version.length() >= 4);
- }
- NaClValidationQuery* NaClValidationQueryContext::CreateQuery() {
- NaClValidationQuery* query = new NaClValidationQuery(db_, profile_key_);
- // Changing the version effectively invalidates existing hashes.
- query->AddData(nacl_version_);
- return query;
- }
- NaClValidationQuery::NaClValidationQuery(NaClValidationDB* db,
- const std::string& profile_key)
- : state_(READY),
- hasher_(crypto::HMAC::SHA256),
- db_(db),
- buffer_length_(0) {
- CHECK(hasher_.Init(profile_key));
- }
- void NaClValidationQuery::AddData(const char* data, size_t length) {
- CHECK(state_ == READY);
- CHECK(buffer_length_ <= sizeof(buffer_));
- // Chrome's HMAC class doesn't support incremental signing. Work around
- // this by using a (small) temporary buffer to accumulate data.
- // Check if there is space in the buffer.
- if (buffer_length_ + kDigestLength > sizeof(buffer_)) {
- // Hash the buffer to make space.
- CompressBuffer();
- }
- // Hash the input data into the buffer. Assumes that sizeof(buffer_) >=
- // kDigestLength * 2 (the buffer can store at least two digests.)
- CHECK(hasher_.Sign(base::StringPiece(data, length),
- reinterpret_cast<unsigned char*>(buffer_ + buffer_length_),
- kDigestLength));
- buffer_length_ += kDigestLength;
- }
- void NaClValidationQuery::AddData(const unsigned char* data, size_t length) {
- AddData(reinterpret_cast<const char*>(data), length);
- }
- void NaClValidationQuery::AddData(const base::StringPiece& data) {
- AddData(data.data(), data.length());
- }
- int NaClValidationQuery::QueryKnownToValidate() {
- CHECK(state_ == READY);
- // It is suspicious if we have less than a digest's worth of data.
- CHECK(buffer_length_ >= kDigestLength);
- CHECK(buffer_length_ <= sizeof(buffer_));
- state_ = GET_CALLED;
- // Ensure the buffer contains only one digest worth of data.
- CompressBuffer();
- return db_->QueryKnownToValidate(std::string(buffer_, buffer_length_));
- }
- void NaClValidationQuery::SetKnownToValidate() {
- CHECK(state_ == GET_CALLED);
- CHECK(buffer_length_ == kDigestLength);
- state_ = SET_CALLED;
- db_->SetKnownToValidate(std::string(buffer_, buffer_length_));
- }
- // Reduce the size of the data in the buffer by hashing it and writing it back
- // to the buffer.
- void NaClValidationQuery::CompressBuffer() {
- // Calculate the digest into a temp buffer. It is likely safe to calculate it
- // directly back into the buffer, but this is an "accidental" semantic we're
- // avoiding depending on.
- unsigned char temp[kDigestLength];
- CHECK(hasher_.Sign(base::StringPiece(buffer_, buffer_length_), temp,
- kDigestLength));
- memcpy(buffer_, temp, kDigestLength);
- buffer_length_ = kDigestLength;
- }
- // OO wrappers
- static void* CreateQuery(void* handle) {
- return static_cast<NaClValidationQueryContext*>(handle)->CreateQuery();
- }
- static void AddData(void* query, const uint8_t* data, size_t length) {
- static_cast<NaClValidationQuery*>(query)->AddData(data, length);
- }
- static int QueryKnownToValidate(void* query) {
- return static_cast<NaClValidationQuery*>(query)->QueryKnownToValidate();
- }
- static void SetKnownToValidate(void* query) {
- static_cast<NaClValidationQuery*>(query)->SetKnownToValidate();
- }
- static void DestroyQuery(void* query) {
- delete static_cast<NaClValidationQuery*>(query);
- }
- struct NaClValidationCache* CreateValidationCache(
- NaClValidationDB* db, const std::string& profile_key,
- const std::string& nacl_version) {
- NaClValidationCache* cache =
- static_cast<NaClValidationCache*>(malloc(sizeof(NaClValidationCache)));
- // Make sure any fields introduced in a cross-repo change are zeroed.
- memset(cache, 0, sizeof(*cache));
- cache->handle = new NaClValidationQueryContext(db, profile_key, nacl_version);
- cache->CreateQuery = CreateQuery;
- cache->AddData = AddData;
- cache->QueryKnownToValidate = QueryKnownToValidate;
- cache->SetKnownToValidate = SetKnownToValidate;
- cache->DestroyQuery = DestroyQuery;
- return cache;
- }
|