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