Add parsers for the Encryption and Encryption-Key HTTP headers.

components/gcm_driver/crypto/encryption_header_parsers.h

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef COMPONENTS_GCM_DRIVER_CRYPTO_ENCRYPTION_HEADER_PARSERS_H_
+#define COMPONENTS_GCM_DRIVER_CRYPTO_ENCRYPTION_HEADER_PARSERS_H_
+
+#include <stdint.h>
+#include <string>
+#include <vector>
+
+namespace gcm {
+
+// Structure representing a parsed and decoded value from the Encryption header.
+// https://tools.ietf.org/html/draft-thomson-http-encryption-01#section-3
+struct EncryptionHeaderValue {
+  std::string keyid;
+  std::string salt;
+  int64_t rs = 4096;
+};
+
+// Structure representing a parsed and decoded value from the Encryption-Key
+// header.
+// https://tools.ietf.org/html/draft-thomson-http-encryption-01#section-4
+struct EncryptionKeyHeaderValue {
+  std::string keyid;
+  std::string key;
+  std::string dh;
+};
+
+// Parses |input| following the syntax of the Encryption HTTP header. Returns
+// whether the |input| could be parsed into |result| successfully.
+bool ParseEncryptionHeader(const std::string& input,
+                           std::vector<EncryptionHeaderValue>* result);
+
+// Parses |input| following the syntax of the Encryption-Key HTTP header.
+// Returns whether the |input| could be parsed into |result| successfully.
+bool ParseEncryptionKeyHeader(const std::string& input,
+                              std::vector<EncryptionKeyHeaderValue>* result);
+
+}  // namespace gcm
+
+#endif  // COMPONENTS_GCM_DRIVER_CRYPTO_ENCRYPTION_HEADER_PARSERS_H_