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ca2f1641c3d7b84f1668b72c2601fae052ca4546
android/libwvdrmengine/oemcrypto/mock/src/oemcrypto_usage_table_mock.cpp
Fred Gylys-Colwell ce535ad21e Report error OEMCrypto_ERROR_ENTRY_IN_USE 
Merge from Widevine repo of http://go/wvgerrit/24311

This CL adds the error OEMCrypto_ERROR_ENTRY_IN_USE to unit tests, the
reference oemcrypto, and the level 3 haystack.

bug: 35879590
Change-Id: Ifbfaf97c0045147aed4498ec0b57d90b26f100d0
2017-03-02 10:55:05 -08:00

736 lines
28 KiB
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Raw Blame History

// Copyright 2013 Google Inc. All Rights Reserved.
//
// Mock implementation of OEMCrypto APIs
//
#include "oemcrypto_usage_table_mock.h"
#include <string.h>
#include <time.h>
#include <string>
#include <vector>
#include <openssl/aes.h>
#include <openssl/hmac.h>
#include <openssl/rand.h>
#include <openssl/sha.h>
#include "file_store.h"
#include "log.h"
#include "oemcrypto_engine_mock.h"
#include "oemcrypto_logging.h"
#include "oemcrypto_old_usage_table_mock.h"
#include "properties.h"
#include "pst_report.h"
#include "string_conversions.h"
#include "wv_cdm_constants.h"
namespace wvoec_mock {
namespace {
const size_t kMagicLength = 8;
const char* kEntryVerification = "USEENTRY";
const char* kHeaderVerification = "USEHEADR";
// Offset into a signed block where we start encrypting. We need to
// skip the signature and the iv.
const size_t kEncryptionOffset = SHA256_DIGEST_LENGTH + SHA256_DIGEST_LENGTH;
// A structure that holds an usage entry and its signature.
struct SignedEntryBlock {
uint8_t signature[SHA256_DIGEST_LENGTH];
uint8_t iv[SHA256_DIGEST_LENGTH];
uint8_t verification[kMagicLength];
StoredUsageEntry data;
};
// This has the data in the header of constant size. There is also an array
// of generation numbers.
struct SignedHeaderBlock {
uint8_t signature[SHA256_DIGEST_LENGTH];
uint8_t iv[SHA256_DIGEST_LENGTH];
uint8_t verification[kMagicLength];
int64_t master_generation;
uint64_t count;
};
} // namespace
UsageTableEntry::UsageTableEntry(UsageTable* table, uint32_t index,
int64_t generation)
: usage_table_(table), recent_decrypt_(false), forbid_report_(true) {
memset(&data_, 0, sizeof(data_));
data_.generation_number = generation;
data_.index = index;
}
UsageTableEntry::~UsageTableEntry() { usage_table_->ReleaseEntry(data_.index); }
OEMCryptoResult UsageTableEntry::SetPST(const uint8_t* pst, size_t pst_length) {
if (pst_length > kMaxPSTLength) return OEMCrypto_ERROR_BUFFER_TOO_LARGE;
data_.pst_length = pst_length;
if (!pst) return OEMCrypto_ERROR_INVALID_CONTEXT;
memcpy(data_.pst, pst, pst_length);
data_.time_of_license_received = time(NULL);
return OEMCrypto_SUCCESS;
}
bool UsageTableEntry::VerifyPST(const uint8_t* pst, size_t pst_length) {
if (pst_length > kMaxPSTLength) return false;
if (data_.pst_length != pst_length) return false;
if (!pst) return false;
return 0 == memcmp(pst, data_.pst, pst_length);
}
bool UsageTableEntry::VerifyMacKeys(const std::vector<uint8_t>& server,
const std::vector<uint8_t>& client) {
return (server.size() == wvcdm::MAC_KEY_SIZE) &&
(client.size() == wvcdm::MAC_KEY_SIZE) &&
(0 == memcmp(&server[0], data_.mac_key_server, wvcdm::MAC_KEY_SIZE)) &&
(0 == memcmp(&client[0], data_.mac_key_client, wvcdm::MAC_KEY_SIZE));
}
bool UsageTableEntry::SetMacKeys(const std::vector<uint8_t>& server,
const std::vector<uint8_t>& client) {
if ((server.size() != wvcdm::MAC_KEY_SIZE) ||
(client.size() != wvcdm::MAC_KEY_SIZE))
return false;
memcpy(data_.mac_key_server, &server[0], wvcdm::MAC_KEY_SIZE);
memcpy(data_.mac_key_client, &client[0], wvcdm::MAC_KEY_SIZE);
return true;
}
bool UsageTableEntry::CheckForUse() {
if (Inactive()) return false;
recent_decrypt_ = true;
if (data_.status == kUnused) {
data_.status = kActive;
data_.time_of_first_decrypt = time(NULL);
data_.generation_number++;
usage_table_->IncrementGeneration();
}
return true;
}
void UsageTableEntry::Deactivate(const std::vector<uint8_t>& pst) {
if (data_.status == kUnused) {
data_.status = kInactiveUnused;
} else if (data_.status == kActive) {
data_.status = kInactiveUsed;
}
forbid_report_ = true;
data_.generation_number++;
usage_table_->IncrementGeneration();
}
OEMCryptoResult UsageTableEntry::ReportUsage(const std::vector<uint8_t>& pst,
uint8_t* buffer,
size_t* buffer_length) {
if (forbid_report_) return OEMCrypto_ERROR_ENTRY_NEEDS_UPDATE;
if (recent_decrypt_) return OEMCrypto_ERROR_ENTRY_NEEDS_UPDATE;
if (pst.size() == 0 || pst.size() > kMaxPSTLength ||
pst.size() != data_.pst_length) {
LOGE("ReportUsage: bad pst length = %d, should be %d.",
pst.size(), data_.pst_length);
return OEMCrypto_ERROR_WRONG_PST;
}
if (memcmp(&pst[0], data_.pst, data_.pst_length)) {
LOGE("ReportUsage: wrong pst %s, should be %s.",
wvcdm::b2a_hex(pst).c_str(),
wvcdm::HexEncode(data_.pst, data_.pst_length).c_str());
return OEMCrypto_ERROR_WRONG_PST;
}
size_t length_needed = wvcdm::Unpacked_PST_Report::report_size(pst.size());
if (*buffer_length < length_needed) {
*buffer_length = length_needed;
return OEMCrypto_ERROR_SHORT_BUFFER;
}
if (!buffer) {
LOGE("ReportUsage: buffer was null pointer.");
return OEMCrypto_ERROR_INVALID_CONTEXT;
}
wvcdm::Unpacked_PST_Report pst_report(buffer);
int64_t now = time(NULL);
pst_report.set_seconds_since_license_received(now -
data_.time_of_license_received);
pst_report.set_seconds_since_first_decrypt(now - data_.time_of_first_decrypt);
pst_report.set_seconds_since_last_decrypt(now - data_.time_of_last_decrypt);
pst_report.set_status(data_.status);
pst_report.set_clock_security_level(kSecureTimer);
pst_report.set_pst_length(data_.pst_length);
memcpy(pst_report.pst(), data_.pst, data_.pst_length);
unsigned int md_len = SHA_DIGEST_LENGTH;
if (!HMAC(EVP_sha1(), data_.mac_key_client, wvcdm::MAC_KEY_SIZE,
buffer + SHA_DIGEST_LENGTH, length_needed - SHA_DIGEST_LENGTH,
pst_report.signature(), &md_len)) {
LOGE("ReportUsage: could not compute signature.");
return OEMCrypto_ERROR_UNKNOWN_FAILURE;
}
return OEMCrypto_SUCCESS;
}
void UsageTableEntry::UpdateAndIncrement() {
if (recent_decrypt_) {
data_.time_of_last_decrypt = time(NULL);
recent_decrypt_ = false;
}
data_.generation_number++;
usage_table_->IncrementGeneration();
forbid_report_ = false;
}
OEMCryptoResult UsageTableEntry::SaveData(CryptoEngine* ce,
SessionContext* session,
uint8_t* signed_buffer,
size_t buffer_size) {
// buffer_size was determined by calling function.
if (buffer_size != SignedEntrySize()) return OEMCrypto_ERROR_UNKNOWN_FAILURE;
std::vector<uint8_t> clear_buffer(buffer_size);
memset(&clear_buffer[0], 0, buffer_size);
memset(signed_buffer, 0, buffer_size);
SignedEntryBlock* clear =
reinterpret_cast<SignedEntryBlock*>(&clear_buffer[0]);
SignedEntryBlock* encrypted =
reinterpret_cast<SignedEntryBlock*>(signed_buffer);
clear->data = this->data_; // Copy the current data.
memcpy(clear->verification, kEntryVerification, kMagicLength);
// This should be encrypted and signed with a device specific key.
// For the reference implementation, I'm just going to use the keybox key.
const bool override_to_real = true;
const std::vector<uint8_t>& key = ce->DeviceRootKey(override_to_real);
// Encrypt the entry.
RAND_bytes(encrypted->iv, wvcdm::KEY_IV_SIZE);
uint8_t iv_buffer[wvcdm::KEY_IV_SIZE]; // working iv buffer.
memcpy(iv_buffer, encrypted->iv, wvcdm::KEY_IV_SIZE);
AES_KEY aes_key;
AES_set_encrypt_key(&key[0], 128, &aes_key);
AES_cbc_encrypt(
&clear_buffer[kEncryptionOffset], &signed_buffer[kEncryptionOffset],
buffer_size - kEncryptionOffset, &aes_key, iv_buffer, AES_ENCRYPT);
// Sign the entry.
unsigned int sig_length = SHA256_DIGEST_LENGTH;
if (!HMAC(EVP_sha256(), &key[0], key.size(),
&signed_buffer[SHA256_DIGEST_LENGTH],
buffer_size - SHA256_DIGEST_LENGTH, encrypted->signature,
&sig_length)) {
LOGE("SaveUsageEntry: Could not sign entry.");
return OEMCrypto_ERROR_UNKNOWN_FAILURE;
}
return OEMCrypto_SUCCESS;
}
OEMCryptoResult UsageTableEntry::LoadData(CryptoEngine* ce, uint32_t index,
const std::vector<uint8_t>& buffer) {
if (buffer.size() < SignedEntrySize()) return OEMCrypto_ERROR_SHORT_BUFFER;
if (buffer.size() > SignedEntrySize())
LOGW("LoadUsageTableEntry: buffer is large. %d > %d", buffer.size(),
SignedEntrySize());
std::vector<uint8_t> clear_buffer(buffer.size());
SignedEntryBlock* clear =
reinterpret_cast<SignedEntryBlock*>(&clear_buffer[0]);
const SignedEntryBlock* encrypted =
reinterpret_cast<const SignedEntryBlock*>(&buffer[0]);
// This should be encrypted and signed with a device specific key.
// For the reference implementation, I'm just going to use the keybox key.
const bool override_to_real = true;
const std::vector<uint8_t>& key = ce->DeviceRootKey(override_to_real);
// Verify the signature of the usage entry. Sign encrypted into clear buffer.
unsigned int sig_length = SHA256_DIGEST_LENGTH;
if (!HMAC(EVP_sha256(), &key[0], key.size(), &buffer[SHA256_DIGEST_LENGTH],
buffer.size() - SHA256_DIGEST_LENGTH, clear->signature,
&sig_length)) {
LOGE("LoadUsageEntry: Could not sign entry.");
return OEMCrypto_ERROR_UNKNOWN_FAILURE;
}
if (memcmp(clear->signature, encrypted->signature, SHA256_DIGEST_LENGTH)) {
LOGE("LoadUsageEntry: Signature did not match.");
LOGE("LoadUsageEntry: Invalid signature given: %s",
wvcdm::HexEncode(encrypted->signature, sig_length).c_str());
LOGE("LoadUsageEntry: Invalid signature computed: %s",
wvcdm::HexEncode(clear->signature, sig_length).c_str());
return OEMCrypto_ERROR_SIGNATURE_FAILURE;
}
// Next, decrypt the entry.
uint8_t iv_buffer[wvcdm::KEY_IV_SIZE];
memcpy(iv_buffer, encrypted->iv, wvcdm::KEY_IV_SIZE);
AES_KEY aes_key;
AES_set_decrypt_key(&key[0], 128, &aes_key);
AES_cbc_encrypt(&buffer[kEncryptionOffset], &clear_buffer[kEncryptionOffset],
buffer.size() - kEncryptionOffset, &aes_key, iv_buffer,
AES_DECRYPT);
// Check the verification string is correct.
if (memcmp(kEntryVerification, clear->verification, kMagicLength)) {
LOGE("LoadUsageEntry: Invalid magic: %s=%8.8s expected: %s=%8.8s",
wvcdm::HexEncode(clear->verification, kMagicLength).c_str(),
clear->verification,
wvcdm::HexEncode(reinterpret_cast<const uint8_t*>(kEntryVerification),
kMagicLength).c_str(),
reinterpret_cast<const uint8_t*>(kEntryVerification));
return OEMCrypto_ERROR_BAD_MAGIC;
}
// Check that the index is correct.
if (index != clear->data.index) {
LOGE("LoadUsageEntry: entry says index is %d, not %d", clear->data.index,
index);
return OEMCrypto_ERROR_INVALID_SESSION;
}
if (clear->data.status > kInactiveUnused) {
LOGE("LoadUsageEntry: entry has bad status %d", clear->data.status);
return OEMCrypto_ERROR_UNKNOWN_FAILURE;
}
this->data_ = clear->data;
return OEMCrypto_SUCCESS;
}
OEMCryptoResult UsageTableEntry::CopyOldUsageEntry(
const std::vector<uint8_t>& pst) {
OldUsageTableEntry* old_entry = usage_table_->FindOldUsageEntry(pst);
if (!old_entry) return OEMCrypto_ERROR_WRONG_PST;
data_.time_of_license_received = old_entry->time_of_license_received_;
data_.time_of_first_decrypt = old_entry->time_of_first_decrypt_;
data_.time_of_last_decrypt = old_entry->time_of_last_decrypt_;
data_.status = old_entry->status_;
if (old_entry->mac_key_server_.size() != wvcdm::MAC_KEY_SIZE) {
LOGE("CopyOldEntry: Old entry has bad server mac key.");
} else {
memcpy(data_.mac_key_server, &(old_entry->mac_key_server_[0]),
wvcdm::MAC_KEY_SIZE);
}
if (old_entry->mac_key_client_.size() != wvcdm::MAC_KEY_SIZE) {
LOGE("CopyOldEntry: Old entry has bad client mac key.");
} else {
memcpy(data_.mac_key_client, &(old_entry->mac_key_client_[0]),
wvcdm::MAC_KEY_SIZE);
}
if (pst.size() > kMaxPSTLength) {
LOGE("CopyOldEntry: PST Length was too large. Truncating.");
data_.pst_length = kMaxPSTLength;
} else {
data_.pst_length = pst.size();
}
memcpy(data_.pst, &pst[0], wvcdm::MAC_KEY_SIZE);
return OEMCrypto_SUCCESS;
}
size_t UsageTableEntry::SignedEntrySize() {
size_t base = sizeof(SignedEntryBlock);
// round up to make even number of blocks:
size_t blocks = (base - 1) / wvcdm::KEY_IV_SIZE + 1;
return blocks * wvcdm::KEY_IV_SIZE;
}
UsageTable::~UsageTable() {
if (old_table_) {
delete old_table_;
old_table_ = NULL;
}
}
size_t UsageTable::SignedHeaderSize(size_t count) {
size_t base = sizeof(SignedHeaderBlock) + count * sizeof(int64_t);
// round up to make even number of blocks:
size_t blocks = (base - 1) / wvcdm::KEY_IV_SIZE + 1;
return blocks * wvcdm::KEY_IV_SIZE;
}
OEMCryptoResult UsageTable::UpdateUsageEntry(SessionContext* session,
UsageTableEntry* entry,
uint8_t* header_buffer,
size_t* header_buffer_length,
uint8_t* entry_buffer,
size_t* entry_buffer_length) {
size_t signed_header_size = SignedHeaderSize(generation_numbers_.size());
if (*entry_buffer_length < UsageTableEntry::SignedEntrySize() ||
*header_buffer_length < signed_header_size) {
*entry_buffer_length = UsageTableEntry::SignedEntrySize();
*header_buffer_length = signed_header_size;
return OEMCrypto_ERROR_SHORT_BUFFER;
}
*entry_buffer_length = UsageTableEntry::SignedEntrySize();
*header_buffer_length = signed_header_size;
if ((!header_buffer) || (!entry_buffer))
return OEMCrypto_ERROR_UNKNOWN_FAILURE;
entry->UpdateAndIncrement();
generation_numbers_[entry->index()] = entry->generation_number();
OEMCryptoResult result =
entry->SaveData(ce_, session, entry_buffer, *entry_buffer_length);
if (result != OEMCrypto_SUCCESS) return result;
result = SaveUsageTableHeader(header_buffer, *header_buffer_length);
return result;
}
OEMCryptoResult UsageTable::CreateNewUsageEntry(SessionContext* session,
UsageTableEntry** entry,
uint32_t* usage_entry_number) {
if (!header_loaded_) {
LOGE("CreateNewUsageEntry: Header not loaded.");
return OEMCrypto_ERROR_UNKNOWN_FAILURE;
}
if (!entry) return OEMCrypto_ERROR_UNKNOWN_FAILURE;
if (!usage_entry_number) return OEMCrypto_ERROR_UNKNOWN_FAILURE;
uint32_t index = generation_numbers_.size();
UsageTableEntry* new_entry =
new UsageTableEntry(this, index, master_generation_number_);
generation_numbers_.push_back(master_generation_number_);
sessions_.push_back(session);
master_generation_number_++;
*entry = new_entry;
*usage_entry_number = index;
return OEMCrypto_SUCCESS;
}
OEMCryptoResult UsageTable::LoadUsageEntry(SessionContext* session,
UsageTableEntry** entry,
uint32_t index,
const std::vector<uint8_t>& buffer) {
if (!header_loaded_) {
LOGE("CreateNewUsageEntry: Header not loaded.");
return OEMCrypto_ERROR_UNKNOWN_FAILURE;
}
if (!entry) return OEMCrypto_ERROR_UNKNOWN_FAILURE;
if (index >= generation_numbers_.size())
return OEMCrypto_ERROR_UNKNOWN_FAILURE;
if (sessions_[index]) {
LOGE("LoadUsageEntry: index %d used by other session.", index);
return OEMCrypto_ERROR_INVALID_SESSION;
}
UsageTableEntry* new_entry =
new UsageTableEntry(this, index, master_generation_number_);
OEMCryptoResult status = new_entry->LoadData(ce_, index, buffer);
if (status != OEMCrypto_SUCCESS) {
delete new_entry;
return status;
}
if (new_entry->generation_number() != generation_numbers_[index]) {
LOGE("Generation SKEW: %ld -> %ld", new_entry->generation_number(),
generation_numbers_[index]);
if ((new_entry->generation_number() + 1 < generation_numbers_[index]) ||
(new_entry->generation_number() - 1 > generation_numbers_[index])) {
delete new_entry;
return OEMCrypto_ERROR_GENERATION_SKEW;
}
status = OEMCrypto_WARNING_GENERATION_SKEW;
}
sessions_[index] = session;
*entry = new_entry;
return status;
}
OEMCryptoResult UsageTable::ShrinkUsageTableHeader(
uint32_t new_table_size, uint8_t* header_buffer,
size_t* header_buffer_length) {
if (new_table_size > generation_numbers_.size()) {
LOGE("OEMCrypto_ShrinkUsageTableHeader: %d > %zd.", new_table_size,
generation_numbers_.size());
return OEMCrypto_ERROR_UNKNOWN_FAILURE;
}
size_t signed_header_size = SignedHeaderSize(new_table_size);
if (*header_buffer_length < signed_header_size) {
*header_buffer_length = signed_header_size;
return OEMCrypto_ERROR_SHORT_BUFFER;
}
*header_buffer_length = signed_header_size;
if (!header_buffer) {
LOGE("OEMCrypto_ShrinkUsageTableHeader: buffer null.");
return OEMCrypto_ERROR_UNKNOWN_FAILURE;
}
for (size_t i = new_table_size; i < sessions_.size(); ++i) {
if (sessions_[i]) {
LOGE("ShrinkUsageTableHeader: session open for %d", i);
return OEMCrypto_ERROR_ENTRY_IN_USE;
}
}
generation_numbers_.resize(new_table_size);
sessions_.resize(new_table_size);
master_generation_number_++;
return SaveUsageTableHeader(header_buffer, *header_buffer_length);
}
OEMCryptoResult UsageTable::SaveUsageTableHeader(uint8_t* signed_buffer,
size_t buffer_size) {
if (!SaveGenerationNumber()) return OEMCrypto_ERROR_UNKNOWN_FAILURE;
size_t count = generation_numbers_.size();
// buffer_size was determined by calling function.
if (buffer_size != SignedHeaderSize(count))
return OEMCrypto_ERROR_UNKNOWN_FAILURE;
std::vector<uint8_t> clear_buffer(buffer_size);
memset(&clear_buffer[0], 0, buffer_size);
memset(signed_buffer, 0, buffer_size);
SignedHeaderBlock* clear =
reinterpret_cast<SignedHeaderBlock*>(&clear_buffer[0]);
SignedHeaderBlock* encrypted =
reinterpret_cast<SignedHeaderBlock*>(signed_buffer);
// Pack the clear data into the clear buffer.
memcpy(clear->verification, kHeaderVerification, kMagicLength);
clear->master_generation = master_generation_number_;
clear->count = count;
// This points to the variable size part of the buffer.
int64_t* stored_generations =
reinterpret_cast<int64_t*>(&clear_buffer[sizeof(SignedHeaderBlock)]);
std::copy(generation_numbers_.begin(), generation_numbers_.begin() + count,
stored_generations);
// This should be encrypted and signed with a device specific key.
// For the reference implementation, I'm just going to use the keybox key.
const bool override_to_real = true;
const std::vector<uint8_t>& key = ce_->DeviceRootKey(override_to_real);
// Encrypt the entry.
RAND_bytes(encrypted->iv, wvcdm::KEY_IV_SIZE);
uint8_t iv_buffer[wvcdm::KEY_IV_SIZE]; // working iv buffer.
memcpy(iv_buffer, encrypted->iv, wvcdm::KEY_IV_SIZE);
AES_KEY aes_key;
AES_set_encrypt_key(&key[0], 128, &aes_key);
AES_cbc_encrypt(
&clear_buffer[kEncryptionOffset], &signed_buffer[kEncryptionOffset],
buffer_size - kEncryptionOffset, &aes_key, iv_buffer, AES_ENCRYPT);
// Sign the entry.
unsigned int sig_length = SHA256_DIGEST_LENGTH;
if (!HMAC(EVP_sha256(), &key[0], key.size(),
&signed_buffer[SHA256_DIGEST_LENGTH],
buffer_size - SHA256_DIGEST_LENGTH, encrypted->signature,
&sig_length)) {
LOGE("SaveUsageHeader: Could not sign entry.");
return OEMCrypto_ERROR_UNKNOWN_FAILURE;
}
return OEMCrypto_SUCCESS;
}
OEMCryptoResult UsageTable::LoadUsageTableHeader(
const std::vector<uint8_t>& buffer) {
if (!LoadGenerationNumber(false)) return OEMCrypto_ERROR_UNKNOWN_FAILURE;
if (buffer.size() < SignedHeaderSize(0)) return OEMCrypto_ERROR_SHORT_BUFFER;
std::vector<uint8_t> clear_buffer(buffer.size());
SignedHeaderBlock* clear =
reinterpret_cast<SignedHeaderBlock*>(&clear_buffer[0]);
const SignedHeaderBlock* encrypted =
reinterpret_cast<const SignedHeaderBlock*>(&buffer[0]);
// This should be encrypted and signed with a device specific key.
// For the reference implementation, I'm just going to use the keybox key.
const bool override_to_real = true;
const std::vector<uint8_t>& key = ce_->DeviceRootKey(override_to_real);
// Verify the signature of the usage entry. Sign encrypted into clear buffer.
unsigned int sig_length = SHA256_DIGEST_LENGTH;
if (!HMAC(EVP_sha256(), &key[0], key.size(), &buffer[SHA256_DIGEST_LENGTH],
buffer.size() - SHA256_DIGEST_LENGTH, clear->signature,
&sig_length)) {
LOGE("LoadUsageTableHeader: Could not sign entry.");
return OEMCrypto_ERROR_UNKNOWN_FAILURE;
}
if (memcmp(clear->signature, encrypted->signature, SHA256_DIGEST_LENGTH)) {
LOGE("LoadUsageTableHeader: Signature did not match.");
LOGE("LoadUsageTableHeader: Invalid signature given: %s",
wvcdm::HexEncode(encrypted->signature, sig_length).c_str());
LOGE("LoadUsageTableHeader: Invalid signature computed: %s",
wvcdm::HexEncode(clear->signature, sig_length).c_str());
return OEMCrypto_ERROR_SIGNATURE_FAILURE;
}
// Next, decrypt the entry.
uint8_t iv_buffer[wvcdm::KEY_IV_SIZE];
memcpy(iv_buffer, encrypted->iv, wvcdm::KEY_IV_SIZE);
AES_KEY aes_key;
AES_set_decrypt_key(&key[0], 128, &aes_key);
AES_cbc_encrypt(&buffer[kEncryptionOffset], &clear_buffer[kEncryptionOffset],
buffer.size() - kEncryptionOffset, &aes_key, iv_buffer,
AES_DECRYPT);
// Check the verification string is correct.
if (memcmp(kHeaderVerification, clear->verification, kMagicLength)) {
LOGE("LoadUsageTableHeader: Invalid magic: %s=%8.8s expected: %s=%8.8s",
wvcdm::HexEncode(clear->verification, kMagicLength).c_str(),
clear->verification,
wvcdm::HexEncode(reinterpret_cast<const uint8_t*>(kHeaderVerification),
kMagicLength).c_str(),
reinterpret_cast<const uint8_t*>(kHeaderVerification));
return OEMCrypto_ERROR_BAD_MAGIC;
}
// Check that size is correct, now that we know what it should be.
if (buffer.size() < SignedHeaderSize(clear->count)) {
return OEMCrypto_ERROR_SHORT_BUFFER;
}
if (buffer.size() > SignedHeaderSize(clear->count)) {
LOGW("LoadUsageTableHeader: buffer is large. %d > %d", buffer.size(),
SignedHeaderSize(clear->count));
}
OEMCryptoResult status = OEMCrypto_SUCCESS;
if (clear->master_generation != master_generation_number_) {
LOGE("Generation SKEW: %ld -> %ld", clear->master_generation,
master_generation_number_);
if ((clear->master_generation + 1 < master_generation_number_) ||
(clear->master_generation - 1 > master_generation_number_)) {
return OEMCrypto_ERROR_GENERATION_SKEW;
}
status = OEMCrypto_WARNING_GENERATION_SKEW;
}
int64_t* stored_generations =
reinterpret_cast<int64_t*>(&clear_buffer[0] + sizeof(SignedHeaderBlock));
generation_numbers_.assign(stored_generations,
stored_generations + clear->count);
sessions_.clear();
sessions_.resize(clear->count);
header_loaded_ = true;
return status;
}
OEMCryptoResult UsageTable::MoveEntry(UsageTableEntry* entry,
uint32_t new_index) {
if (new_index >= generation_numbers_.size()) {
LOGE("MoveEntry: index beyond end of usage table %d >= %d", new_index,
generation_numbers_.size());
return OEMCrypto_ERROR_INVALID_CONTEXT;
}
if (sessions_[new_index]) {
LOGE("MoveEntry: session open for %d", new_index);
return OEMCrypto_ERROR_ENTRY_IN_USE;
}
if (!entry) {
LOGE("MoveEntry: null entry");
return OEMCrypto_ERROR_UNKNOWN_FAILURE;
}
sessions_[new_index] = sessions_[entry->index()];
sessions_[entry->index()] = 0;
entry->set_index(new_index);
generation_numbers_[new_index] = master_generation_number_;
entry->set_generation_number(master_generation_number_);
master_generation_number_++;
return OEMCrypto_SUCCESS;
}
void UsageTable::IncrementGeneration() {
master_generation_number_++;
SaveGenerationNumber();
}
bool UsageTable::SaveGenerationNumber() {
wvcdm::FileSystem* file_system = ce_->file_system();
std::string path;
// Note: this path is OK for a real implementation, but using security level 1
// would be better.
if (!wvcdm::Properties::GetDeviceFilesBasePath(wvcdm::kSecurityLevelL3,
&path)) {
LOGE("UsageTable: Unable to get base path");
return false;
}
// On a real implementation, you should NOT put the generation number in
// a file in user space. It should be stored in secure memory.
std::string filename = path + "GenerationNumber.dat";
wvcdm::File* file = file_system->Open(
filename, wvcdm::FileSystem::kCreate | wvcdm::FileSystem::kTruncate);
if (!file) {
LOGE("UsageTable: File open failed: %s", path.c_str());
return false;
}
file->Write(reinterpret_cast<char*>(&master_generation_number_),
sizeof(int64_t));
file->Close();
return true;
}
bool UsageTable::LoadGenerationNumber(bool or_make_new_one) {
wvcdm::FileSystem* file_system = ce_->file_system();
std::string path;
// Note: this path is OK for a real implementation, but using security level 1
// would be better.
if (!wvcdm::Properties::GetDeviceFilesBasePath(wvcdm::kSecurityLevelL3,
&path)) {
LOGE("UsageTable: Unable to get base path");
return false;
}
// On a real implementation, you should NOT put the generation number in
// a file in user space. It should be stored in secure memory.
std::string filename = path + "GenerationNumber.dat";
wvcdm::File* file = file_system->Open(filename, wvcdm::FileSystem::kReadOnly);
if (!file) {
if (or_make_new_one) {
RAND_bytes(reinterpret_cast<uint8_t*>(&master_generation_number_),
sizeof(int64_t));
return true;
}
LOGE("UsageTable: File open failed: %s (clearing table)", path.c_str());
master_generation_number_ = 0;
return false;
}
file->Read(reinterpret_cast<char*>(&master_generation_number_),
sizeof(int64_t));
file->Close();
return true;
}
OEMCryptoResult UsageTable::CreateUsageTableHeader(
uint8_t* header_buffer, size_t* header_buffer_length) {
size_t signed_header_size = SignedHeaderSize(0);
if (*header_buffer_length < signed_header_size) {
*header_buffer_length = signed_header_size;
return OEMCrypto_ERROR_SHORT_BUFFER;
}
*header_buffer_length = signed_header_size;
if (!LoadGenerationNumber(true)) return OEMCrypto_ERROR_UNKNOWN_FAILURE;
// Make sure there are no entries that are currently tied to an open session.
for (size_t i=0; i < sessions_.size(); ++i) {
if (sessions_[i] != NULL) {
LOGE("CreateUsageTableHeader: index %d used by session.", i);
return OEMCrypto_ERROR_INVALID_SESSION;
}
}
sessions_.clear();
generation_numbers_.clear();
header_loaded_ = true;
return SaveUsageTableHeader(header_buffer, *header_buffer_length);
}
OldUsageTableEntry* UsageTable::FindOldUsageEntry(
const std::vector<uint8_t>& pst) {
if (!old_table_) old_table_ = new OldUsageTable(ce_);
return old_table_->FindEntry(pst);
}
OEMCryptoResult UsageTable::DeleteOldUsageTable() {
if (old_table_) {
old_table_->Clear();
delete old_table_;
old_table_ = NULL;
}
OldUsageTable::DeleteFile(ce_);
return OEMCrypto_SUCCESS;
}
OEMCryptoResult UsageTable::CreateOldUsageEntry(
uint64_t time_since_license_received, uint64_t time_since_first_decrypt,
uint64_t time_since_last_decrypt, OEMCrypto_Usage_Entry_Status status,
uint8_t* server_mac_key, uint8_t* client_mac_key, const uint8_t* pst,
size_t pst_length) {
if (!old_table_) old_table_ = new OldUsageTable(ce_);
std::vector<uint8_t> pstv(pst, pst+pst_length);
OldUsageTableEntry *old_entry = old_table_->CreateEntry(pstv);
int64_t now = time(NULL);
old_entry->time_of_license_received_ = now - time_since_license_received;
old_entry->time_of_first_decrypt_ = now - time_since_first_decrypt;
old_entry->time_of_last_decrypt_ = now - time_since_last_decrypt;
old_entry->status_ = status;
old_entry->mac_key_server_.assign(server_mac_key,
server_mac_key + wvcdm::MAC_KEY_SIZE);
old_entry->mac_key_client_.assign(client_mac_key,
client_mac_key + wvcdm::MAC_KEY_SIZE);
return OEMCrypto_SUCCESS;
}
} // namespace wvoec_mock
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