html_viewer: Move webcrypto to a place where html_viewer can use it.

content/child/webcrypto/webcrypto_util.h

-// Copyright 2014 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 CONTENT_CHILD_WEBCRYPTO_WEBCRYPTO_UTIL_H_
-#define CONTENT_CHILD_WEBCRYPTO_WEBCRYPTO_UTIL_H_
-
-#include <stdint.h>
-#include <string>
-
-#include "base/values.h"
-#include "content/common/content_export.h"
-#include "third_party/WebKit/public/platform/WebCryptoAlgorithm.h"
-#include "third_party/WebKit/public/platform/WebCryptoKey.h"
-
-namespace content {
-
-namespace webcrypto {
-
-class Status;
-
-// Creates a WebCryptoAlgorithm without any parameters.
-CONTENT_EXPORT blink::WebCryptoAlgorithm CreateAlgorithm(
-    blink::WebCryptoAlgorithmId id);
-
-// Creates an HMAC import algorithm whose inner hash algorithm is determined by
-// the specified algorithm ID. It is an error to call this method with a hash
-// algorithm that is not SHA*.
-CONTENT_EXPORT blink::WebCryptoAlgorithm CreateHmacImportAlgorithm(
-    blink::WebCryptoAlgorithmId hash_id,
-    unsigned int length_bits);
-
-// Same as above but without specifying a length.
-CONTENT_EXPORT blink::WebCryptoAlgorithm CreateHmacImportAlgorithmNoLength(
-    blink::WebCryptoAlgorithmId hash_id);
-
-// Creates an import algorithm for RSA algorithms that take a hash.
-// It is an error to call this with a hash_id that is not a SHA*.
-CONTENT_EXPORT blink::WebCryptoAlgorithm CreateRsaHashedImportAlgorithm(
-    blink::WebCryptoAlgorithmId id,
-    blink::WebCryptoAlgorithmId hash_id);
-
-// Creates an import algorithm for EC keys.
-CONTENT_EXPORT blink::WebCryptoAlgorithm CreateEcImportAlgorithm(
-    blink::WebCryptoAlgorithmId id,
-    blink::WebCryptoNamedCurve named_curve);
-
-// Returns true if the set bits in b make up a subset of the set bits in a.
-bool ContainsKeyUsages(blink::WebCryptoKeyUsageMask a,
-                       blink::WebCryptoKeyUsageMask b);
-
-bool KeyUsageAllows(const blink::WebCryptoKey& key,
-                    const blink::WebCryptoKeyUsage usage);
-
-Status GetAesGcmTagLengthInBits(const blink::WebCryptoAesGcmParams* params,
-                                unsigned int* tag_length_bits);
-
-Status GetAesKeyGenLengthInBits(const blink::WebCryptoAesKeyGenParams* params,
-                                unsigned int* keylen_bits);
-
-Status GetHmacKeyGenLengthInBits(const blink::WebCryptoHmacKeyGenParams* params,
-                                 unsigned int* keylen_bits);
-
-// Gets the requested key length in bits for an HMAC import operation.
-Status GetHmacImportKeyLengthBits(
-    const blink::WebCryptoHmacImportParams* params,
-    unsigned int key_data_byte_length,
-    unsigned int* keylen_bits);
-
-Status VerifyAesKeyLengthForImport(unsigned int keylen_bytes);
-
-Status CheckKeyCreationUsages(blink::WebCryptoKeyUsageMask all_possible_usages,
-                              blink::WebCryptoKeyUsageMask actual_usages,
-                              bool allow_empty_usages);
-
-// Extracts the public exponent and modulus length from the Blink parameters.
-// On success it is guaranteed that:
-//   * public_exponent is either 3 or 65537
-//   * modulus_length_bits is a multiple of 8
-//   * modulus_length is >= 256
-//   * modulus_length is <= 16K
-Status GetRsaKeyGenParameters(
-    const blink::WebCryptoRsaHashedKeyGenParams* params,
-    unsigned int* public_exponent,
-    unsigned int* modulus_length_bits);
-
-// Verifies that |usages| is valid when importing a key of the given format.
-Status VerifyUsagesBeforeImportAsymmetricKey(
-    blink::WebCryptoKeyFormat format,
-    blink::WebCryptoKeyUsageMask all_public_key_usages,
-    blink::WebCryptoKeyUsageMask all_private_key_usages,
-    blink::WebCryptoKeyUsageMask usages);
-
-// Truncates an octet string to a particular bit length. This is accomplished by
-// resizing to the closest byte length, and then zero-ing the unused
-// least-significant bits of the final byte.
-//
-// It is an error to call this function with a bit length that is larger than
-// that of |bytes|.
-//
-// TODO(eroman): This operation is not yet defined by the WebCrypto spec,
-// however this is a reasonable interpretation:
-// https://www.w3.org/Bugs/Public/show_bug.cgi?id=27402
-void TruncateToBitLength(size_t length_bits, std::vector<uint8_t>* bytes);
-
-// Rounds a bit count (up) to the nearest byte count.
-//
-// This is mathematically equivalent to (x + 7) / 8, however has no
-// possibility of integer overflow.
-template <typename T>
-T NumBitsToBytes(T x) {
-  return (x / 8) + (7 + (x % 8)) / 8;
-}
-
-// The "get key length" operation for AES keys.
-Status GetAesKeyLength(const blink::WebCryptoAlgorithm& key_length_algorithm,
-                       bool* has_length_bits,
-                       unsigned int* length_bits);
-
-// The "get key length" operation for HMAC keys.
-Status GetHmacKeyLength(const blink::WebCryptoAlgorithm& key_length_algorithm,
-                        bool* has_length_bits,
-                        unsigned int* length_bits);
-
-// Splits the combined usages given to GenerateKey() into the respective usages
-// for the public key and private key. Returns an error if the usages are
-// invalid.
-Status GetUsagesForGenerateAsymmetricKey(
-    blink::WebCryptoKeyUsageMask combined_usages,
-    blink::WebCryptoKeyUsageMask all_public_usages,
-    blink::WebCryptoKeyUsageMask all_private_usages,
-    blink::WebCryptoKeyUsageMask* public_usages,
-    blink::WebCryptoKeyUsageMask* private_usages);
-
-}  // namespace webcrypto
-
-}  // namespace content
-
-#endif  // CONTENT_CHILD_WEBCRYPTO_WEBCRYPTO_UTIL_H_