Export media_cas_packager_sdk

common/signature_util.cc

@@ -0,0 +1,66 @@
+////////////////////////////////////////////////////////////////////////////////
+// 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