Relocate QUICHE files into quiche/ directory within the quiche repo, and change the relative include paths accordingly.

PiperOrigin-RevId: 440164720
Change-Id: I64d8a975d08888a3a86f6c51908e63d5cd45fa35
diff --git a/quiche/quic/core/crypto/quic_hkdf.h b/quiche/quic/core/crypto/quic_hkdf.h
new file mode 100644
index 0000000..0040447
--- /dev/null
+++ b/quiche/quic/core/crypto/quic_hkdf.h
@@ -0,0 +1,76 @@
+// Copyright 2018 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 QUICHE_QUIC_CORE_CRYPTO_QUIC_HKDF_H_
+#define QUICHE_QUIC_CORE_CRYPTO_QUIC_HKDF_H_
+
+#include <vector>
+
+#include "absl/strings/string_view.h"
+#include "quiche/quic/platform/api/quic_export.h"
+
+namespace quic {
+
+// QuicHKDF implements the key derivation function specified in RFC 5869
+// (using SHA-256) and outputs key material, as needed by QUIC.
+// See https://tools.ietf.org/html/rfc5869 for details.
+class QUIC_EXPORT_PRIVATE QuicHKDF {
+ public:
+  // |secret|: the input shared secret (or, from RFC 5869, the IKM).
+  // |salt|: an (optional) public salt / non-secret random value. While
+  // optional, callers are strongly recommended to provide a salt. There is no
+  // added security value in making this larger than the SHA-256 block size of
+  // 64 bytes.
+  // |info|: an (optional) label to distinguish different uses of HKDF. It is
+  // optional context and application specific information (can be a zero-length
+  // string).
+  // |key_bytes_to_generate|: the number of bytes of key material to generate
+  // for both client and server.
+  // |iv_bytes_to_generate|: the number of bytes of IV to generate for both
+  // client and server.
+  // |subkey_secret_bytes_to_generate|: the number of bytes of subkey secret to
+  // generate, shared between client and server.
+  QuicHKDF(absl::string_view secret,
+           absl::string_view salt,
+           absl::string_view info,
+           size_t key_bytes_to_generate,
+           size_t iv_bytes_to_generate,
+           size_t subkey_secret_bytes_to_generate);
+
+  // An alternative constructor that allows the client and server key/IV
+  // lengths to be different.
+  QuicHKDF(absl::string_view secret,
+           absl::string_view salt,
+           absl::string_view info,
+           size_t client_key_bytes_to_generate,
+           size_t server_key_bytes_to_generate,
+           size_t client_iv_bytes_to_generate,
+           size_t server_iv_bytes_to_generate,
+           size_t subkey_secret_bytes_to_generate);
+
+  ~QuicHKDF();
+
+  absl::string_view client_write_key() const { return client_write_key_; }
+  absl::string_view client_write_iv() const { return client_write_iv_; }
+  absl::string_view server_write_key() const { return server_write_key_; }
+  absl::string_view server_write_iv() const { return server_write_iv_; }
+  absl::string_view subkey_secret() const { return subkey_secret_; }
+  absl::string_view client_hp_key() const { return client_hp_key_; }
+  absl::string_view server_hp_key() const { return server_hp_key_; }
+
+ private:
+  std::vector<uint8_t> output_;
+
+  absl::string_view client_write_key_;
+  absl::string_view server_write_key_;
+  absl::string_view client_write_iv_;
+  absl::string_view server_write_iv_;
+  absl::string_view subkey_secret_;
+  absl::string_view client_hp_key_;
+  absl::string_view server_hp_key_;
+};
+
+}  // namespace quic
+
+#endif  // QUICHE_QUIC_CORE_CRYPTO_QUIC_HKDF_H_