Files
media_cas_packager_sdk_source/common/signing_key_util.cc
2018-10-01 14:59:29 -07:00

45 lines
1.4 KiB
C++

////////////////////////////////////////////////////////////////////////////////
// Copyright 2016 Google LLC.
//
// This software is licensed under the terms defined in the Widevine Master
// License Agreement. For a copy of this agreement, please contact
// widevine-licensing@google.com.
////////////////////////////////////////////////////////////////////////////////
#include "common/signing_key_util.h"
#include "glog/logging.h"
#include "common/crypto_util.h"
#include "protos/public/license_protocol.pb.h"
namespace widevine {
using crypto_util::kSigningKeySizeBits;
uint32_t SigningKeyMaterialSize(ProtocolVersion protocol_version) {
if (protocol_version <= VERSION_2_0) {
return kSigningKeySizeBits;
} else {
return kSigningKeySizeBits * 2;
}
}
using crypto_util::kSigningKeySizeBytes;
std::string GetClientSigningKey(const std::string& derived_key,
ProtocolVersion protocol_version) {
if (protocol_version == VERSION_2_0) {
DCHECK(derived_key.size() >= kSigningKeySizeBytes);
return derived_key.substr(0, kSigningKeySizeBytes);
} else {
DCHECK(derived_key.size() >= kSigningKeySizeBytes * 2);
return derived_key.substr(kSigningKeySizeBytes, kSigningKeySizeBytes);
}
}
std::string GetServerSigningKey(const std::string& derived_key) {
DCHECK(derived_key.size() >= kSigningKeySizeBytes);
return derived_key.substr(0, kSigningKeySizeBytes);
}
} // namespace widevine