Move crypto files out of base, to a top level directory.

crypto/sha2.h

+// Copyright (c) 2011 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 CRYPTO_SHA2_H_
+#define CRYPTO_SHA2_H_
+#pragma once
+
+#include <string>
+
+namespace crypto {
+
+// These functions perform SHA-256 operations.
+//
+// Functions for SHA-384 and SHA-512 can be added when the need arises.
+
+enum {
+  SHA256_LENGTH = 32  // length in bytes of a SHA-256 hash
+};
+
+// Computes the SHA-256 hash of the input string 'str' and stores the first
+// 'len' bytes of the hash in the output buffer 'output'.  If 'len' > 32,
+// only 32 bytes (the full hash) are stored in the 'output' buffer.
+void SHA256HashString(const std::string& str,
+                      void* output, size_t len);
+
+// Convenience version of the above that returns the result in a 32-byte
+// string.
+std::string SHA256HashString(const std::string& str);
+
+}  // namespace crypto
+
+#endif  // CRYPTO_SHA2_H_