crypto/rsa_private_key.h

   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_RSA_PRIVATE_KEY_H_
   6 #define CRYPTO_RSA_PRIVATE_KEY_H_
   7
   8 #include "build/build_config.h"
   9
  10 #include <list>
  11 #include <vector>
  12
  13 #include "base/basictypes.h"
  14 #include "crypto/crypto_export.h"
  15
  16 #if defined(USE_NSS)
  17 #include "base/gtest_prod_util.h"
  18 #endif
  19
  20 #if defined(USE_OPENSSL)
  21 // Forward declaration for openssl/*.h
  22 typedef struct evp_pkey_st EVP_PKEY;
  23 #else
  24 // Forward declaration.
  25 typedef struct PK11SlotInfoStr PK11SlotInfo;
  26 typedef struct SECKEYPrivateKeyStr SECKEYPrivateKey;
  27 typedef struct SECKEYPublicKeyStr SECKEYPublicKey;
  28 #endif
  29
  30
  31 namespace crypto {
  32
  33 // Used internally by RSAPrivateKey for serializing and deserializing
  34 // PKCS #8 PrivateKeyInfo and PublicKeyInfo.
  35 class PrivateKeyInfoCodec {
  36  public:
  37
  38   // ASN.1 encoding of the AlgorithmIdentifier from PKCS #8.
  39   static const uint8 kRsaAlgorithmIdentifier[];
  40
  41   // ASN.1 tags for some types we use.
  42   static const uint8 kBitStringTag = 0x03;
  43   static const uint8 kIntegerTag = 0x02;
  44   static const uint8 kNullTag = 0x05;
  45   static const uint8 kOctetStringTag = 0x04;
  46   static const uint8 kSequenceTag = 0x30;
  47
  48   // |big_endian| here specifies the byte-significance of the integer components
  49   // that will be parsed & serialized (modulus(), etc...) during Import(),
  50   // Export() and ExportPublicKeyInfo() -- not the ASN.1 DER encoding of the
  51   // PrivateKeyInfo/PublicKeyInfo (which is always big-endian).
  52   explicit PrivateKeyInfoCodec(bool big_endian);
  53
  54   ~PrivateKeyInfoCodec();
  55
  56   // Exports the contents of the integer components to the ASN.1 DER encoding
  57   // of the PrivateKeyInfo structure to |output|.
  58   bool Export(std::vector<uint8>* output);
  59
  60   // Exports the contents of the integer components to the ASN.1 DER encoding
  61   // of the PublicKeyInfo structure to |output|.
  62   bool ExportPublicKeyInfo(std::vector<uint8>* output);
  63
  64   // Exports the contents of the integer components to the ASN.1 DER encoding
  65   // of the RSAPublicKey structure to |output|.
  66   bool ExportPublicKey(std::vector<uint8>* output);
  67
  68   // Parses the ASN.1 DER encoding of the PrivateKeyInfo structure in |input|
  69   // and populates the integer components with |big_endian_| byte-significance.
  70   // IMPORTANT NOTE: This is currently *not* security-approved for importing
  71   // keys from unstrusted sources.
  72   bool Import(const std::vector<uint8>& input);
  73
  74   // Accessors to the contents of the integer components of the PrivateKeyInfo
  75   // structure.
  76   std::vector<uint8>* modulus() { return &modulus_; };
  77   std::vector<uint8>* public_exponent() { return &public_exponent_; };
  78   std::vector<uint8>* private_exponent() { return &private_exponent_; };
  79   std::vector<uint8>* prime1() { return &prime1_; };
  80   std::vector<uint8>* prime2() { return &prime2_; };
  81   std::vector<uint8>* exponent1() { return &exponent1_; };
  82   std::vector<uint8>* exponent2() { return &exponent2_; };
  83   std::vector<uint8>* coefficient() { return &coefficient_; };
  84
  85  private:
  86   // Utility wrappers for PrependIntegerImpl that use the class's |big_endian_|
  87   // value.
  88   void PrependInteger(const std::vector<uint8>& in, std::list<uint8>* out);
  89   void PrependInteger(uint8* val, int num_bytes, std::list<uint8>* data);
  90
  91   // Prepends the integer stored in |val| - |val + num_bytes| with |big_endian|
  92   // byte-significance into |data| as an ASN.1 integer.
  93   void PrependIntegerImpl(uint8* val,
  94                           int num_bytes,
  95                           std::list<uint8>* data,
  96                           bool big_endian);
  97
  98   // Utility wrappers for ReadIntegerImpl that use the class's |big_endian_|
  99   // value.
 100   bool ReadInteger(uint8** pos, uint8* end, std::vector<uint8>* out);
 101   bool ReadIntegerWithExpectedSize(uint8** pos,
 102                                    uint8* end,
 103                                    size_t expected_size,
 104                                    std::vector<uint8>* out);
 105
 106   // Reads an ASN.1 integer from |pos|, and stores the result into |out| with
 107   // |big_endian| byte-significance.
 108   bool ReadIntegerImpl(uint8** pos,
 109                        uint8* end,
 110                        std::vector<uint8>* out,
 111                        bool big_endian);
 112
 113   // Prepends the integer stored in |val|, starting a index |start|, for
 114   // |num_bytes| bytes onto |data|.
 115   void PrependBytes(uint8* val,
 116                     int start,
 117                     int num_bytes,
 118                     std::list<uint8>* data);
 119
 120   // Helper to prepend an ASN.1 length field.
 121   void PrependLength(size_t size, std::list<uint8>* data);
 122
 123   // Helper to prepend an ASN.1 type header.
 124   void PrependTypeHeaderAndLength(uint8 type,
 125                                   uint32 length,
 126                                   std::list<uint8>* output);
 127
 128   // Helper to prepend an ASN.1 bit string
 129   void PrependBitString(uint8* val, int num_bytes, std::list<uint8>* output);
 130
 131   // Read an ASN.1 length field. This also checks that the length does not
 132   // extend beyond |end|.
 133   bool ReadLength(uint8** pos, uint8* end, uint32* result);
 134
 135   // Read an ASN.1 type header and its length.
 136   bool ReadTypeHeaderAndLength(uint8** pos,
 137                                uint8* end,
 138                                uint8 expected_tag,
 139                                uint32* length);
 140
 141   // Read an ASN.1 sequence declaration. This consumes the type header and
 142   // length field, but not the contents of the sequence.
 143   bool ReadSequence(uint8** pos, uint8* end);
 144
 145   // Read the RSA AlgorithmIdentifier.
 146   bool ReadAlgorithmIdentifier(uint8** pos, uint8* end);
 147
 148   // Read one of the two version fields in PrivateKeyInfo.
 149   bool ReadVersion(uint8** pos, uint8* end);
 150
 151   // The byte-significance of the stored components (modulus, etc..).
 152   bool big_endian_;
 153
 154   // Component integers of the PrivateKeyInfo
 155   std::vector<uint8> modulus_;
 156   std::vector<uint8> public_exponent_;
 157   std::vector<uint8> private_exponent_;
 158   std::vector<uint8> prime1_;
 159   std::vector<uint8> prime2_;
 160   std::vector<uint8> exponent1_;
 161   std::vector<uint8> exponent2_;
 162   std::vector<uint8> coefficient_;
 163
 164   DISALLOW_COPY_AND_ASSIGN(PrivateKeyInfoCodec);
 165 };
 166
 167 // Encapsulates an RSA private key. Can be used to generate new keys, export
 168 // keys to other formats, or to extract a public key.
 169 // TODO(hclam): This class should be ref-counted so it can be reused easily.
 170 class CRYPTO_EXPORT RSAPrivateKey {
 171  public:
 172   ~RSAPrivateKey();
 173
 174   // Create a new random instance. Can return NULL if initialization fails.
 175   static RSAPrivateKey* Create(uint16 num_bits);
 176
 177   // Create a new instance by importing an existing private key. The format is
 178   // an ASN.1-encoded PrivateKeyInfo block from PKCS #8. This can return NULL if
 179   // initialization fails.
 180   static RSAPrivateKey* CreateFromPrivateKeyInfo(
 181       const std::vector<uint8>& input);
 182
 183 #if defined(USE_NSS)
 184   // Create a new random instance in |slot|. Can return NULL if initialization
 185   // fails.  The created key is permanent and is not exportable in plaintext
 186   // form.
 187   static RSAPrivateKey* CreateSensitive(PK11SlotInfo* slot, uint16 num_bits);
 188
 189   // Create a new instance in |slot| by importing an existing private key. The
 190   // format is an ASN.1-encoded PrivateKeyInfo block from PKCS #8. This can
 191   // return NULL if initialization fails.
 192   // The created key is permanent and is not exportable in plaintext form.
 193   static RSAPrivateKey* CreateSensitiveFromPrivateKeyInfo(
 194       PK11SlotInfo* slot,
 195       const std::vector<uint8>& input);
 196
 197   // Create a new instance by referencing an existing private key
 198   // structure.  Does not import the key.
 199   static RSAPrivateKey* CreateFromKey(SECKEYPrivateKey* key);
 200
 201   // Import an existing public key, and then search for the private
 202   // half in the key database. The format of the public key blob is is
 203   // an X509 SubjectPublicKeyInfo block. This can return NULL if
 204   // initialization fails or the private key cannot be found.  The
 205   // caller takes ownership of the returned object, but nothing new is
 206   // created in the key database.
 207   static RSAPrivateKey* FindFromPublicKeyInfo(
 208       const std::vector<uint8>& input);
 209 #endif
 210
 211 #if defined(USE_OPENSSL)
 212   EVP_PKEY* key() { return key_; }
 213 #else
 214   SECKEYPrivateKey* key() { return key_; }
 215   SECKEYPublicKey* public_key() { return public_key_; }
 216 #endif
 217
 218   // Creates a copy of the object.
 219   RSAPrivateKey* Copy() const;
 220
 221   // Exports the private key to a PKCS #1 PrivateKey block.
 222   bool ExportPrivateKey(std::vector<uint8>* output) const;
 223
 224   // Exports the public key to an X509 SubjectPublicKeyInfo block.
 225   bool ExportPublicKey(std::vector<uint8>* output) const;
 226
 227  private:
 228 #if defined(USE_NSS)
 229   FRIEND_TEST_ALL_PREFIXES(RSAPrivateKeyNSSTest, FindFromPublicKey);
 230   FRIEND_TEST_ALL_PREFIXES(RSAPrivateKeyNSSTest, FailedFindFromPublicKey);
 231 #endif
 232
 233   // Constructor is private. Use one of the Create*() or Find*()
 234   // methods above instead.
 235   RSAPrivateKey();
 236
 237 #if !defined(USE_OPENSSL)
 238   // Shared helper for Create() and CreateSensitive().
 239   // TODO(cmasone): consider replacing |permanent| and |sensitive| with a
 240   //                flags arg created by ORing together some enumerated values.
 241   // Note: |permanent| is only supported when USE_NSS is defined.
 242   static RSAPrivateKey* CreateWithParams(PK11SlotInfo* slot,
 243                                          uint16 num_bits,
 244                                          bool permanent,
 245                                          bool sensitive);
 246
 247   // Shared helper for CreateFromPrivateKeyInfo() and
 248   // CreateSensitiveFromPrivateKeyInfo().
 249   // Note: |permanent| is only supported when USE_NSS is defined.
 250   static RSAPrivateKey* CreateFromPrivateKeyInfoWithParams(
 251       PK11SlotInfo* slot,
 252       const std::vector<uint8>& input,
 253       bool permanent,
 254       bool sensitive);
 255 #endif
 256
 257 #if defined(USE_OPENSSL)
 258   EVP_PKEY* key_;
 259 #else
 260   SECKEYPrivateKey* key_;
 261   SECKEYPublicKey* public_key_;
 262 #endif
 263
 264   DISALLOW_COPY_AND_ASSIGN(RSAPrivateKey);
 265 };
 266
 267 }  // namespace crypto
 268
 269 #endif  // CRYPTO_RSA_PRIVATE_KEY_H_