1 // Copyright 2012 The Chromium Authors 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef CRYPTO_EC_PRIVATE_KEY_H_ 6 #define CRYPTO_EC_PRIVATE_KEY_H_ 7 8 #include <stddef.h> 9 #include <stdint.h> 10 11 #include <memory> 12 #include <string> 13 #include <vector> 14 15 #include "base/containers/span.h" 16 #include "build/build_config.h" 17 #include "crypto/crypto_export.h" 18 #include "third_party/boringssl/src/include/openssl/base.h" 19 20 namespace crypto { 21 22 // Encapsulates an elliptic curve (EC) private key. Can be used to generate new 23 // keys, export keys to other formats, or to extract a public key. 24 // TODO(mattm): make this and RSAPrivateKey implement some PrivateKey interface. 25 // (The difference in types of key() and public_key() make this a little 26 // tricky.) 27 class CRYPTO_EXPORT ECPrivateKey { 28 public: 29 ECPrivateKey(const ECPrivateKey&) = delete; 30 ECPrivateKey& operator=(const ECPrivateKey&) = delete; 31 32 ~ECPrivateKey(); 33 34 // Creates a new random instance. Can return nullptr if initialization fails. 35 // The created key will use the NIST P-256 curve. 36 static std::unique_ptr<ECPrivateKey> Create(); 37 38 // Create a new instance by importing an existing private key. The format is 39 // an ASN.1-encoded PrivateKeyInfo block from PKCS #8. This can return 40 // nullptr if initialization fails. 41 static std::unique_ptr<ECPrivateKey> CreateFromPrivateKeyInfo( 42 base::span<const uint8_t> input); 43 44 // Creates a new instance by importing an existing key pair. 45 // The key pair is given as an ASN.1-encoded PKCS #8 EncryptedPrivateKeyInfo 46 // block with empty password and an X.509 SubjectPublicKeyInfo block. 47 // Returns nullptr if initialization fails. 48 // 49 // This function is deprecated. Use CreateFromPrivateKeyInfo for new code. 50 // See https://crbug.com/603319. 51 static std::unique_ptr<ECPrivateKey> CreateFromEncryptedPrivateKeyInfo( 52 base::span<const uint8_t> encrypted_private_key_info); 53 54 // Returns a copy of the object. 55 std::unique_ptr<ECPrivateKey> Copy() const; 56 key()57 EVP_PKEY* key() const { return key_.get(); } 58 59 // Exports the private key to a PKCS #8 PrivateKeyInfo block. 60 bool ExportPrivateKey(std::vector<uint8_t>* output) const; 61 62 // Exports the public key to an X.509 SubjectPublicKeyInfo block. 63 bool ExportPublicKey(std::vector<uint8_t>* output) const; 64 65 // Exports the public key as an EC point in X9.62 uncompressed form. Note this 66 // includes the leading 0x04 byte. 67 bool ExportRawPublicKey(std::string* output) const; 68 69 private: 70 // Constructor is private. Use one of the Create*() methods above instead. 71 ECPrivateKey(); 72 73 bssl::UniquePtr<EVP_PKEY> key_; 74 }; 75 76 } // namespace crypto 77 78 #endif // CRYPTO_EC_PRIVATE_KEY_H_ 79