ec.cc | Explore in Territory

// Copyright 2014 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifdef UNSAFE_BUFFERS_BUILD
// TODO(crbug.com/40285824): Remove this and convert code to safer constructs.
#pragma allow_unsafe_buffers
#endif

#include "components/webcrypto/algorithms/ec.h"

#include <stddef.h>

#include <string_view>
#include <utility>

#include "base/containers/span.h"
#include "components/webcrypto/algorithms/asymmetric_key_util.h"
#include "components/webcrypto/algorithms/util.h"
#include "components/webcrypto/blink_key_handle.h"
#include "components/webcrypto/generate_key_result.h"
#include "components/webcrypto/jwk.h"
#include "components/webcrypto/status.h"
#include "crypto/openssl_util.h"
#include "third_party/blink/public/platform/web_crypto_algorithm_params.h"
#include "third_party/blink/public/platform/web_crypto_key_algorithm.h"
#include "third_party/boringssl/src/include/openssl/bn.h"
#include "third_party/boringssl/src/include/openssl/bytestring.h"
#include "third_party/boringssl/src/include/openssl/ec.h"
#include "third_party/boringssl/src/include/openssl/ec_key.h"
#include "third_party/boringssl/src/include/openssl/evp.h"
#include "third_party/boringssl/src/include/openssl/mem.h"

namespace webcrypto {

namespace {

// Maps a blink::WebCryptoNamedCurve to the corresponding NID used by
// BoringSSL.
Status WebCryptoCurveToNid(blink::WebCryptoNamedCurve named_curve, int* nid) { … }

// Maps a BoringSSL NID to the corresponding WebCrypto named curve.
Status NidToWebCryptoCurve(int nid, blink::WebCryptoNamedCurve* named_curve) { … }

struct JwkCrvMapping { … };

const JwkCrvMapping kJwkCrvMappings[] = …;

// Gets the "crv" parameter from a JWK and converts it to a WebCryptoNamedCurve.
Status ReadJwkCrv(const JwkReader& jwk,
                  blink::WebCryptoNamedCurve* named_curve) { … }

// Converts a WebCryptoNamedCurve to an equivalent JWK "crv".
Status WebCryptoCurveToJwkCrv(blink::WebCryptoNamedCurve named_curve,
                              std::string* jwk_crv) { … }

// Verifies that an EC key imported from PKCS8 or SPKI format is correct.
// This involves verifying the key validity, and the NID for the named curve.
// Also removes the EC_PKEY_NO_PUBKEY flag if present.
Status VerifyEcKeyAfterSpkiOrPkcs8Import(
    EVP_PKEY* pkey,
    blink::WebCryptoNamedCurve expected_named_curve) { … }

// Creates an EC_KEY for the given WebCryptoNamedCurve.
Status CreateEC_KEY(blink::WebCryptoNamedCurve named_curve,
                    bssl::UniquePtr<EC_KEY>* ec) { … }

// Writes an unsigned BIGNUM into |jwk|, zero-padding it to a length of
// |padded_length|.
Status WritePaddedBIGNUM(std::string_view member_name,
                         const BIGNUM* value,
                         size_t padded_length,
                         JwkWriter* jwk) { … }

// Reads a fixed length BIGNUM from a JWK.
Status ReadPaddedBIGNUM(const JwkReader& jwk,
                        std::string_view member_name,
                        size_t expected_length,
                        bssl::UniquePtr<BIGNUM>* out) { … }

int GetGroupDegreeInBytes(EC_KEY* ec) { … }

// Extracts the public key as affine coordinates (x,y).
Status GetPublicKey(EC_KEY* ec,
                    bssl::UniquePtr<BIGNUM>* x,
                    bssl::UniquePtr<BIGNUM>* y) { … }

// Synthesizes an import algorithm given a key algorithm, so that
// deserialization can re-use the ImportKey*() methods.
blink::WebCryptoAlgorithm SynthesizeImportAlgorithmForClone(
    const blink::WebCryptoKeyAlgorithm& algorithm) { … }

}  // namespace

Status EcAlgorithm::GenerateKey(const blink::WebCryptoAlgorithm& algorithm,
                                bool extractable,
                                blink::WebCryptoKeyUsageMask combined_usages,
                                GenerateKeyResult* result) const { … }

Status EcAlgorithm::ImportKey(blink::WebCryptoKeyFormat format,
                              base::span<const uint8_t> key_data,
                              const blink::WebCryptoAlgorithm& algorithm,
                              bool extractable,
                              blink::WebCryptoKeyUsageMask usages,
                              blink::WebCryptoKey* key) const { … }

Status EcAlgorithm::ExportKey(blink::WebCryptoKeyFormat format,
                              const blink::WebCryptoKey& key,
                              std::vector<uint8_t>* buffer) const { … }

Status EcAlgorithm::ImportKeyRaw(base::span<const uint8_t> key_data,
                                 const blink::WebCryptoAlgorithm& algorithm,
                                 bool extractable,
                                 blink::WebCryptoKeyUsageMask usages,
                                 blink::WebCryptoKey* key) const { … }

Status EcAlgorithm::ImportKeyPkcs8(base::span<const uint8_t> key_data,
                                   const blink::WebCryptoAlgorithm& algorithm,
                                   bool extractable,
                                   blink::WebCryptoKeyUsageMask usages,
                                   blink::WebCryptoKey* key) const { … }

Status EcAlgorithm::ImportKeySpki(base::span<const uint8_t> key_data,
                                  const blink::WebCryptoAlgorithm& algorithm,
                                  bool extractable,
                                  blink::WebCryptoKeyUsageMask usages,
                                  blink::WebCryptoKey* key) const { … }

// The format for JWK EC keys is given by:
// https://tools.ietf.org/html/draft-ietf-jose-json-web-algorithms-36#section-6.2
Status EcAlgorithm::ImportKeyJwk(base::span<const uint8_t> key_data,
                                 const blink::WebCryptoAlgorithm& algorithm,
                                 bool extractable,
                                 blink::WebCryptoKeyUsageMask usages,
                                 blink::WebCryptoKey* key) const { … }

Status EcAlgorithm::ExportKeyRaw(const blink::WebCryptoKey& key,
                                 std::vector<uint8_t>* buffer) const { … }

Status EcAlgorithm::ExportKeyPkcs8(const blink::WebCryptoKey& key,
                                   std::vector<uint8_t>* buffer) const { … }

Status EcAlgorithm::ExportKeySpki(const blink::WebCryptoKey& key,
                                  std::vector<uint8_t>* buffer) const { … }

// The format for JWK EC keys is given by:
// https://tools.ietf.org/html/draft-ietf-jose-json-web-algorithms-36#section-6.2
Status EcAlgorithm::ExportKeyJwk(const blink::WebCryptoKey& key,
                                 std::vector<uint8_t>* buffer) const { … }

// TODO(eroman): Defer import to the crypto thread. http://crbug.com/430763
Status EcAlgorithm::DeserializeKeyForClone(
    const blink::WebCryptoKeyAlgorithm& algorithm,
    blink::WebCryptoKeyType type,
    bool extractable,
    blink::WebCryptoKeyUsageMask usages,
    base::span<const uint8_t> key_data,
    blink::WebCryptoKey* key) const { … }

}  // namespace webcrypto
chromium/components/webcrypto/algorithms/ec.cc
