Replace hardcoded parameters

common/signer_public_key.cc

@@ -0,0 +1,69 @@
+////////////////////////////////////////////////////////////////////////////////
+// Copyright 2019 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/signer_public_key.h"
+
+#include "absl/memory/memory.h"
+#include "common/ec_key.h"
+#include "common/rsa_key.h"
+
+namespace widevine {
+
+// SignerPublicKeyImpl is a generic implementation of SignerPublicKey. The
+// initialization details are in the SignerPublicKey factory method.
+template <typename T>
+class SignerPublicKeyImpl : public SignerPublicKey {
+ public:
+  explicit SignerPublicKeyImpl(std::unique_ptr<T> signer_public_key)
+      : signer_public_key_(std::move(signer_public_key)) {}
+  ~SignerPublicKeyImpl() override {}
+  SignerPublicKeyImpl(const SignerPublicKeyImpl&) = delete;
+  SignerPublicKeyImpl& operator=(const SignerPublicKeyImpl&) = delete;
+
+  bool VerifySignature(const std::string& message,
+                       const std::string& signature) const override {
+    if (!signer_public_key_->VerifySignature(message, signature)) {
+      return false;
+    }
+    return true;
+  }
+
+ private:
+  std::unique_ptr<T> signer_public_key_;
+};
+
+std::unique_ptr<SignerPublicKey> SignerPublicKey::Create(
+    const std::string& signer_public_key, DrmCertificate::Algorithm algorithm) {
+  switch (algorithm) {
+    case DrmCertificate::RSA: {
+      std::unique_ptr<RsaPublicKey> public_key(
+          RsaPublicKey::Create(signer_public_key));
+      if (public_key == nullptr) {
+        return nullptr;
+      }
+      return absl::make_unique<SignerPublicKeyImpl<RsaPublicKey>>(
+          std::move(public_key));
+    }
+    // All supported ECC curves are specified here.
+    case DrmCertificate::ECC_SECP256R1:
+    case DrmCertificate::ECC_SECP384R1:
+    case DrmCertificate::ECC_SECP521R1: {
+      std::unique_ptr<ECPublicKey> public_key =
+          ECPublicKey::Create(signer_public_key);
+      if (public_key == nullptr) {
+        return nullptr;
+      }
+      return absl::make_unique<SignerPublicKeyImpl<ECPublicKey>>(
+          std::move(public_key));
+    }
+    default:
+      return nullptr;
+  }
+}
+
+}  // namespace widevine