ec_private_key.h revision 0c4f26a46430b8c503c65f5cae1d2b6876d53e30 
1// Copyright (c) 2012 The Chromium Authors. All rights reserved.
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/macros.h"
16#include "build/build_config.h"
17#include "crypto/crypto_export.h"
18
19#if defined(USE_OPENSSL)
20// Forward declaration for openssl/*.h
21typedef struct evp_pkey_st EVP_PKEY;
22#else
23// Forward declaration.
24typedef struct CERTSubjectPublicKeyInfoStr CERTSubjectPublicKeyInfo;
25typedef struct PK11SlotInfoStr PK11SlotInfo;
26typedef struct SECKEYPrivateKeyStr SECKEYPrivateKey;
27typedef struct SECKEYPublicKeyStr SECKEYPublicKey;
28#endif
29
30namespace crypto {
31
32// Encapsulates an elliptic curve (EC) private key. Can be used to generate new
33// keys, export keys to other formats, or to extract a public key.
34// TODO(mattm): make this and RSAPrivateKey implement some PrivateKey interface.
35// (The difference in types of key() and public_key() make this a little
36// tricky.)
37class CRYPTO_EXPORT ECPrivateKey {
38 public:
39  ~ECPrivateKey();
40
41  // Creates a new random instance. Can return nullptr if initialization fails.
42  // The created key will use the NIST P-256 curve.
43  // TODO(mattm): Add a curve parameter.
44  static std::unique_ptr<ECPrivateKey> Create();
45
46  // Create a new instance by importing an existing private key. The format is
47  // an ASN.1-encoded PrivateKeyInfo block from PKCS #8. This can return
48  // nullptr if initialization fails.
49  static std::unique_ptr<ECPrivateKey> CreateFromPrivateKeyInfo(
50      const std::vector<uint8_t>& input);
51
52  // Creates a new instance by importing an existing key pair.
53  // The key pair is given as an ASN.1-encoded PKCS #8 EncryptedPrivateKeyInfo
54  // block and an X.509 SubjectPublicKeyInfo block.
55  // Returns nullptr if initialization fails.
56  //
57  // This function is deprecated. Use CreateFromPrivateKeyInfo for new code.
58  // See https://crbug.com/603319.
59  static std::unique_ptr<ECPrivateKey> CreateFromEncryptedPrivateKeyInfo(
60      const std::string& password,
61      const std::vector<uint8_t>& encrypted_private_key_info,
62      const std::vector<uint8_t>& subject_public_key_info);
63
64#if !defined(USE_OPENSSL)
65  // Imports the key pair into |slot| and returns in |public_key| and |key|.
66  // Shortcut for code that needs to keep a reference directly to NSS types
67  // without having to create a ECPrivateKey object and make a copy of them.
68  // TODO(mattm): move this function to some NSS util file.
69  static bool ImportFromEncryptedPrivateKeyInfo(
70      PK11SlotInfo* slot,
71      const std::string& password,
72      const uint8_t* encrypted_private_key_info,
73      size_t encrypted_private_key_info_len,
74      CERTSubjectPublicKeyInfo* decoded_spki,
75      bool permanent,
76      bool sensitive,
77      SECKEYPrivateKey** key,
78      SECKEYPublicKey** public_key);
79#endif
80
81  // Returns a copy of the object.
82  std::unique_ptr<ECPrivateKey> Copy() const;
83
84#if defined(USE_OPENSSL)
85  EVP_PKEY* key() { return key_; }
86#else
87  SECKEYPrivateKey* key() { return key_; }
88  SECKEYPublicKey* public_key() { return public_key_; }
89#endif
90
91  // Exports the private key to a PKCS #8 PrivateKeyInfo block.
92  bool ExportPrivateKey(std::vector<uint8_t>* output) const;
93
94  // Exports the private key as an ASN.1-encoded PKCS #8 EncryptedPrivateKeyInfo
95  // block and the public key as an X.509 SubjectPublicKeyInfo block.
96  // The |password| and |iterations| are used as inputs to the key derivation
97  // function for generating the encryption key.  PKCS #5 recommends a minimum
98  // of 1000 iterations, on modern systems a larger value may be preferrable.
99  //
100  // This function is deprecated. Use ExportPrivateKey for new code. See
101  // https://crbug.com/603319.
102  bool ExportEncryptedPrivateKey(const std::string& password,
103                                 int iterations,
104                                 std::vector<uint8_t>* output) const;
105
106  // Exports the public key to an X.509 SubjectPublicKeyInfo block.
107  bool ExportPublicKey(std::vector<uint8_t>* output) const;
108
109  // Exports the public key as an EC point in the uncompressed point format.
110  bool ExportRawPublicKey(std::string* output) const;
111
112 private:
113  // Constructor is private. Use one of the Create*() methods above instead.
114  ECPrivateKey();
115
116#if defined(USE_OPENSSL)
117  EVP_PKEY* key_;
118#else
119  SECKEYPrivateKey* key_;
120  SECKEYPublicKey* public_key_;
121#endif
122
123  DISALLOW_COPY_AND_ASSIGN(ECPrivateKey);
124};
125
126
127}  // namespace crypto
128
129#endif  // CRYPTO_EC_PRIVATE_KEY_H_
130