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

67 lines
2.2 KiB
C++

////////////////////////////////////////////////////////////////////////////////
// Copyright 2018 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/signature_util.h"
#include <memory>
#include <string>
#include "util/status.h"
#include "common/aes_cbc_util.h"
#include "common/rsa_key.h"
#include "common/sha_util.h"
namespace widevine {
namespace signature_util {
util::Status GenerateAesSignature(const std::string& message, const std::string& aes_key,
const std::string& aes_iv, std::string* signature) {
if (signature == nullptr) {
return util::Status(util::error::INVALID_ARGUMENT, "signature is nullptr");
}
std::string hash = Sha1_Hash(message);
if (hash.empty()) {
return util::Status(util::error::INTERNAL, "Computed hash is empty");
}
std::string sig = crypto_util::EncryptAesCbc(aes_key, aes_iv, hash);
if (sig.empty()) {
return util::Status(util::error::INTERNAL,
"Computed AES signature is empty");
}
*signature = sig;
return util::OkStatus();
}
util::Status GenerateRsaSignature(const std::string& message,
const std::string& private_key,
std::string* signature) {
if (signature == nullptr) {
return util::Status(util::error::INVALID_ARGUMENT, "signature is nullptr");
}
std::unique_ptr<RsaPrivateKey> rsa_private_key(
RsaPrivateKey::Create(private_key));
if (rsa_private_key == nullptr) {
return util::Status(util::error::INTERNAL,
"Failed to construct a RsaPrivateKey");
}
std::string sig;
if (!rsa_private_key->GenerateSignature(message, &sig)) {
return util::Status(util::error::INTERNAL,
"Failed to generate a RSA signature");
}
if (sig.empty()) {
return util::Status(util::error::INTERNAL,
"Computed RSA signature is empty");
}
*signature = sig;
return util::OkStatus();
}
} // namespace signature_util
} // namespace widevine