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 #if defined(USE_OPENSSL)
  11 // Forward declaration for openssl/*.h
  12 typedef struct evp_pkey_st EVP_PKEY;
  13 #elif defined(USE_NSS)
  14 // Forward declaration.
  15 struct SECKEYPrivateKeyStr;
  16 struct SECKEYPublicKeyStr;
  17 #elif defined(OS_MACOSX)
  18 #include <Security/cssm.h>
  19 #endif
  20
  21 #include <list>
  22 #include <vector>
  23
  24 #include "base/basictypes.h"
  25 #include "crypto/crypto_export.h"
  26
  27 #if defined(OS_WIN)
  28 #include "crypto/scoped_capi_types.h"
  29 #endif
  30 #if defined(USE_NSS)
  31 #include "base/gtest_prod_util.h"
  32 #endif
  33
  34 namespace crypto {
  35
  36 // Used internally by RSAPrivateKey for serializing and deserializing
  37 // PKCS #8 PrivateKeyInfo and PublicKeyInfo.
  38 class PrivateKeyInfoCodec {
  39  public:
  40
  41   // ASN.1 encoding of the AlgorithmIdentifier from PKCS #8.
  42   static const uint8 kRsaAlgorithmIdentifier[];
  43
  44   // ASN.1 tags for some types we use.
  45   static const uint8 kBitStringTag = 0x03;
  46   static const uint8 kIntegerTag = 0x02;
  47   static const uint8 kNullTag = 0x05;
  48   static const uint8 kOctetStringTag = 0x04;
  49   static const uint8 kSequenceTag = 0x30;
  50
  51   // |big_endian| here specifies the byte-significance of the integer components
  52   // that will be parsed & serialized (modulus(), etc...) during Import(),
  53   // Export() and ExportPublicKeyInfo() -- not the ASN.1 DER encoding of the
  54   // PrivateKeyInfo/PublicKeyInfo (which is always big-endian).
  55   explicit PrivateKeyInfoCodec(bool big_endian);
  56
  57   ~PrivateKeyInfoCodec();
  58
  59   // Exports the contents of the integer components to the ASN.1 DER encoding
  60   // of the PrivateKeyInfo structure to |output|.
  61   bool Export(std::vector<uint8>* output);
  62
  63   // Exports the contents of the integer components to the ASN.1 DER encoding
  64   // of the PublicKeyInfo structure to |output|.
  65   bool ExportPublicKeyInfo(std::vector<uint8>* output);
  66
  67   // Exports the contents of the integer components to the ASN.1 DER encoding
  68   // of the RSAPublicKey structure to |output|.
  69   bool ExportPublicKey(std::vector<uint8>* output);
  70
  71   // Parses the ASN.1 DER encoding of the PrivateKeyInfo structure in |input|
  72   // and populates the integer components with |big_endian_| byte-significance.
  73   // IMPORTANT NOTE: This is currently *not* security-approved for importing
  74   // keys from unstrusted sources.
  75   bool Import(const std::vector<uint8>& input);
  76
  77   // Accessors to the contents of the integer components of the PrivateKeyInfo
  78   // structure.
  79   std::vector<uint8>* modulus() { return &modulus_; };
  80   std::vector<uint8>* public_exponent() { return &public_exponent_; };
  81   std::vector<uint8>* private_exponent() { return &private_exponent_; };
  82   std::vector<uint8>* prime1() { return &prime1_; };
  83   std::vector<uint8>* prime2() { return &prime2_; };
  84   std::vector<uint8>* exponent1() { return &exponent1_; };
  85   std::vector<uint8>* exponent2() { return &exponent2_; };
  86   std::vector<uint8>* coefficient() { return &coefficient_; };
  87
  88  private:
  89   // Utility wrappers for PrependIntegerImpl that use the class's |big_endian_|
  90   // value.
  91   void PrependInteger(const std::vector<uint8>& in, std::list<uint8>* out);
  92   void PrependInteger(uint8* val, int num_bytes, std::list<uint8>* data);
  93
  94   // Prepends the integer stored in |val| - |val + num_bytes| with |big_endian|
  95   // byte-significance into |data| as an ASN.1 integer.
  96   void PrependIntegerImpl(uint8* val,
  97                           int num_bytes,
  98                           std::list<uint8>* data,
  99                           bool big_endian);
 100
 101   // Utility wrappers for ReadIntegerImpl that use the class's |big_endian_|
 102   // value.
 103   bool ReadInteger(uint8** pos, uint8* end, std::vector<uint8>* out);
 104   bool ReadIntegerWithExpectedSize(uint8** pos,
 105                                    uint8* end,
 106                                    size_t expected_size,
 107                                    std::vector<uint8>* out);
 108
 109   // Reads an ASN.1 integer from |pos|, and stores the result into |out| with
 110   // |big_endian| byte-significance.
 111   bool ReadIntegerImpl(uint8** pos,
 112                        uint8* end,
 113                        std::vector<uint8>* out,
 114                        bool big_endian);
 115
 116   // Prepends the integer stored in |val|, starting a index |start|, for
 117   // |num_bytes| bytes onto |data|.
 118   void PrependBytes(uint8* val,
 119                     int start,
 120                     int num_bytes,
 121                     std::list<uint8>* data);
 122
 123   // Helper to prepend an ASN.1 length field.
 124   void PrependLength(size_t size, std::list<uint8>* data);
 125
 126   // Helper to prepend an ASN.1 type header.
 127   void PrependTypeHeaderAndLength(uint8 type,
 128                                   uint32 length,
 129                                   std::list<uint8>* output);
 130
 131   // Helper to prepend an ASN.1 bit string
 132   void PrependBitString(uint8* val, int num_bytes, std::list<uint8>* output);
 133
 134   // Read an ASN.1 length field. This also checks that the length does not
 135   // extend beyond |end|.
 136   bool ReadLength(uint8** pos, uint8* end, uint32* result);
 137
 138   // Read an ASN.1 type header and its length.
 139   bool ReadTypeHeaderAndLength(uint8** pos,
 140                                uint8* end,
 141                                uint8 expected_tag,
 142                                uint32* length);
 143
 144   // Read an ASN.1 sequence declaration. This consumes the type header and
 145   // length field, but not the contents of the sequence.
 146   bool ReadSequence(uint8** pos, uint8* end);
 147
 148   // Read the RSA AlgorithmIdentifier.
 149   bool ReadAlgorithmIdentifier(uint8** pos, uint8* end);
 150
 151   // Read one of the two version fields in PrivateKeyInfo.
 152   bool ReadVersion(uint8** pos, uint8* end);
 153
 154   // The byte-significance of the stored components (modulus, etc..).
 155   bool big_endian_;
 156
 157   // Component integers of the PrivateKeyInfo
 158   std::vector<uint8> modulus_;
 159   std::vector<uint8> public_exponent_;
 160   std::vector<uint8> private_exponent_;
 161   std::vector<uint8> prime1_;
 162   std::vector<uint8> prime2_;
 163   std::vector<uint8> exponent1_;
 164   std::vector<uint8> exponent2_;
 165   std::vector<uint8> coefficient_;
 166
 167   DISALLOW_COPY_AND_ASSIGN(PrivateKeyInfoCodec);
 168 };
 169
 170 // Encapsulates an RSA private key. Can be used to generate new keys, export
 171 // keys to other formats, or to extract a public key.
 172 // TODO(hclam): This class should be ref-counted so it can be reused easily.
 173 class CRYPTO_EXPORT RSAPrivateKey {
 174  public:
 175   ~RSAPrivateKey();
 176
 177   // Create a new random instance. Can return NULL if initialization fails.
 178   static RSAPrivateKey* Create(uint16 num_bits);
 179
 180   // Create a new random instance. Can return NULL if initialization fails.
 181   // The created key is permanent and is not exportable in plaintext form.
 182   //
 183   // NOTE: Currently only available if USE_NSS is defined.
 184   static RSAPrivateKey* CreateSensitive(uint16 num_bits);
 185
 186   // Create a new instance by importing an existing private key. The format is
 187   // an ASN.1-encoded PrivateKeyInfo block from PKCS #8. This can return NULL if
 188   // initialization fails.
 189   static RSAPrivateKey* CreateFromPrivateKeyInfo(
 190       const std::vector<uint8>& input);
 191
 192   // Create a new instance by importing an existing private key. The format is
 193   // an ASN.1-encoded PrivateKeyInfo block from PKCS #8. This can return NULL if
 194   // initialization fails.
 195   // The created key is permanent and is not exportable in plaintext form.
 196   //
 197   // NOTE: Currently only available if USE_NSS is defined.
 198   static RSAPrivateKey* CreateSensitiveFromPrivateKeyInfo(
 199       const std::vector<uint8>& input);
 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   //
 208   // NOTE: Currently only available if USE_NSS is defined.
 209   static RSAPrivateKey* FindFromPublicKeyInfo(
 210       const std::vector<uint8>& input);
 211
 212 #if defined(USE_OPENSSL)
 213   EVP_PKEY* key() { return key_; }
 214 #elif defined(USE_NSS)
 215   SECKEYPrivateKeyStr* key() { return key_; }
 216   SECKEYPublicKeyStr* public_key() { return public_key_; }
 217 #elif defined(OS_WIN)
 218   HCRYPTPROV provider() { return provider_; }
 219   HCRYPTKEY key() { return key_; }
 220 #elif defined(OS_MACOSX)
 221   CSSM_KEY_PTR key() { return &key_; }
 222   CSSM_KEY_PTR public_key() { return &public_key_; }
 223 #endif
 224
 225   // Creates a copy of the object.
 226   RSAPrivateKey* Copy() const;
 227
 228   // Exports the private key to a PKCS #1 PrivateKey block.
 229   bool ExportPrivateKey(std::vector<uint8>* output) const;
 230
 231   // Exports the public key to an X509 SubjectPublicKeyInfo block.
 232   bool ExportPublicKey(std::vector<uint8>* output) const;
 233
 234  private:
 235 #if defined(USE_NSS)
 236   FRIEND_TEST_ALL_PREFIXES(RSAPrivateKeyNSSTest, FindFromPublicKey);
 237   FRIEND_TEST_ALL_PREFIXES(RSAPrivateKeyNSSTest, FailedFindFromPublicKey);
 238 #endif
 239
 240   // Constructor is private. Use one of the Create*() or Find*()
 241   // methods above instead.
 242   RSAPrivateKey();
 243
 244   // Shared helper for Create() and CreateSensitive().
 245   // TODO(cmasone): consider replacing |permanent| and |sensitive| with a
 246   //                flags arg created by ORing together some enumerated values.
 247   static RSAPrivateKey* CreateWithParams(uint16 num_bits,
 248                                          bool permanent,
 249                                          bool sensitive);
 250
 251   // Shared helper for CreateFromPrivateKeyInfo() and
 252   // CreateSensitiveFromPrivateKeyInfo().
 253   static RSAPrivateKey* CreateFromPrivateKeyInfoWithParams(
 254       const std::vector<uint8>& input, bool permanent, bool sensitive);
 255
 256 #if defined(USE_OPENSSL)
 257   EVP_PKEY* key_;
 258 #elif defined(USE_NSS)
 259   SECKEYPrivateKeyStr* key_;
 260   SECKEYPublicKeyStr* public_key_;
 261 #elif defined(OS_WIN)
 262   bool InitProvider();
 263
 264   ScopedHCRYPTPROV provider_;
 265   ScopedHCRYPTKEY key_;
 266 #elif defined(OS_MACOSX)
 267   CSSM_KEY key_;
 268   CSSM_KEY public_key_;
 269 #endif
 270
 271   DISALLOW_COPY_AND_ASSIGN(RSAPrivateKey);
 272 };
 273
 274 }  // namespace crypto
 275
 276 #endif  // CRYPTO_RSA_PRIVATE_KEY_H_