crypto/rsa_private_key_win.cc

   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 #include "crypto/rsa_private_key.h"
   6
   7 #include <list>
   8
   9 #include "base/logging.h"
  10 #include "base/memory/scoped_ptr.h"
  11 #include "base/string_util.h"
  12
  13 #pragma comment(lib, "crypt32.lib")
  14
  15 namespace crypto {
  16
  17 // static
  18 RSAPrivateKey* RSAPrivateKey::Create(uint16 num_bits) {
  19   scoped_ptr<RSAPrivateKey> result(new RSAPrivateKey);
  20   if (!result->InitProvider())
  21     return NULL;
  22
  23   DWORD flags = CRYPT_EXPORTABLE;
  24
  25   // The size is encoded as the upper 16 bits of the flags. :: sigh ::.
  26   flags |= (num_bits << 16);
  27   if (!CryptGenKey(result->provider_, CALG_RSA_SIGN, flags,
  28                    result->key_.receive()))
  29     return NULL;
  30
  31   return result.release();
  32 }
  33
  34 // static
  35 RSAPrivateKey* RSAPrivateKey::CreateSensitive(uint16 num_bits) {
  36   NOTIMPLEMENTED();
  37   return NULL;
  38 }
  39
  40 // static
  41 RSAPrivateKey* RSAPrivateKey::CreateFromPrivateKeyInfo(
  42     const std::vector<uint8>& input) {
  43   scoped_ptr<RSAPrivateKey> result(new RSAPrivateKey);
  44   if (!result->InitProvider())
  45     return NULL;
  46
  47   PrivateKeyInfoCodec pki(false);  // Little-Endian
  48   if (!pki.Import(input))
  49     return NULL;
  50
  51   size_t blob_size = sizeof(PUBLICKEYSTRUC) +
  52                      sizeof(RSAPUBKEY) +
  53                      pki.modulus()->size() +
  54                      pki.prime1()->size() +
  55                      pki.prime2()->size() +
  56                      pki.exponent1()->size() +
  57                      pki.exponent2()->size() +
  58                      pki.coefficient()->size() +
  59                      pki.private_exponent()->size();
  60   scoped_array<BYTE> blob(new BYTE[blob_size]);
  61
  62   uint8* dest = blob.get();
  63   PUBLICKEYSTRUC* public_key_struc = reinterpret_cast<PUBLICKEYSTRUC*>(dest);
  64   public_key_struc->bType = PRIVATEKEYBLOB;
  65   public_key_struc->bVersion = 0x02;
  66   public_key_struc->reserved = 0;
  67   public_key_struc->aiKeyAlg = CALG_RSA_SIGN;
  68   dest += sizeof(PUBLICKEYSTRUC);
  69
  70   RSAPUBKEY* rsa_pub_key = reinterpret_cast<RSAPUBKEY*>(dest);
  71   rsa_pub_key->magic = 0x32415352;
  72   rsa_pub_key->bitlen = pki.modulus()->size() * 8;
  73   int public_exponent_int = 0;
  74   for (size_t i = pki.public_exponent()->size(); i > 0; --i) {
  75     public_exponent_int <<= 8;
  76     public_exponent_int |= (*pki.public_exponent())[i - 1];
  77   }
  78   rsa_pub_key->pubexp = public_exponent_int;
  79   dest += sizeof(RSAPUBKEY);
  80
  81   memcpy(dest, &pki.modulus()->front(), pki.modulus()->size());
  82   dest += pki.modulus()->size();
  83   memcpy(dest, &pki.prime1()->front(), pki.prime1()->size());
  84   dest += pki.prime1()->size();
  85   memcpy(dest, &pki.prime2()->front(), pki.prime2()->size());
  86   dest += pki.prime2()->size();
  87   memcpy(dest, &pki.exponent1()->front(), pki.exponent1()->size());
  88   dest += pki.exponent1()->size();
  89   memcpy(dest, &pki.exponent2()->front(), pki.exponent2()->size());
  90   dest += pki.exponent2()->size();
  91   memcpy(dest, &pki.coefficient()->front(), pki.coefficient()->size());
  92   dest += pki.coefficient()->size();
  93   memcpy(dest, &pki.private_exponent()->front(),
  94          pki.private_exponent()->size());
  95   dest += pki.private_exponent()->size();
  96
  97   if (dest != blob.get() + blob_size) {
  98     NOTREACHED();
  99     return NULL;
 100   }
 101   if (!CryptImportKey(result->provider_,
 102                       reinterpret_cast<uint8*>(public_key_struc),
 103                       static_cast<DWORD>(blob_size), 0, CRYPT_EXPORTABLE,
 104                       result->key_.receive())) {
 105     return NULL;
 106   }
 107
 108   return result.release();
 109 }
 110
 111 // static
 112 RSAPrivateKey* RSAPrivateKey::CreateSensitiveFromPrivateKeyInfo(
 113     const std::vector<uint8>& input) {
 114   NOTIMPLEMENTED();
 115   return NULL;
 116 }
 117
 118 // static
 119 RSAPrivateKey* RSAPrivateKey::FindFromPublicKeyInfo(
 120     const std::vector<uint8>& input) {
 121   NOTIMPLEMENTED();
 122   return NULL;
 123 }
 124
 125 RSAPrivateKey::RSAPrivateKey() : provider_(NULL), key_(NULL) {}
 126
 127 RSAPrivateKey::~RSAPrivateKey() {}
 128
 129 bool RSAPrivateKey::InitProvider() {
 130   return FALSE != CryptAcquireContext(provider_.receive(), NULL, NULL,
 131                                       PROV_RSA_FULL, CRYPT_VERIFYCONTEXT);
 132 }
 133
 134 RSAPrivateKey* RSAPrivateKey::Copy() const {
 135   scoped_ptr<RSAPrivateKey> copy(new RSAPrivateKey());
 136   if (!CryptContextAddRef(provider_, NULL, 0)) {
 137     NOTREACHED();
 138     return NULL;
 139   }
 140   copy->provider_.reset(provider_.get());
 141   if (!CryptDuplicateKey(key_.get(), NULL, 0, copy->key_.receive()))
 142     return NULL;
 143   return copy.release();
 144 }
 145
 146 bool RSAPrivateKey::ExportPrivateKey(std::vector<uint8>* output) const {
 147   // Export the key
 148   DWORD blob_length = 0;
 149   if (!CryptExportKey(key_, 0, PRIVATEKEYBLOB, 0, NULL, &blob_length)) {
 150     NOTREACHED();
 151     return false;
 152   }
 153
 154   scoped_array<uint8> blob(new uint8[blob_length]);
 155   if (!CryptExportKey(key_, 0, PRIVATEKEYBLOB, 0, blob.get(), &blob_length)) {
 156     NOTREACHED();
 157     return false;
 158   }
 159
 160   uint8* pos = blob.get();
 161   PUBLICKEYSTRUC *publickey_struct = reinterpret_cast<PUBLICKEYSTRUC*>(pos);
 162   pos += sizeof(PUBLICKEYSTRUC);
 163
 164   RSAPUBKEY *rsa_pub_key = reinterpret_cast<RSAPUBKEY*>(pos);
 165   pos += sizeof(RSAPUBKEY);
 166
 167   int mod_size = rsa_pub_key->bitlen / 8;
 168   int primes_size = rsa_pub_key->bitlen / 16;
 169
 170   PrivateKeyInfoCodec pki(false);  // Little-Endian
 171
 172   pki.modulus()->assign(pos, pos + mod_size);
 173   pos += mod_size;
 174
 175   pki.prime1()->assign(pos, pos + primes_size);
 176   pos += primes_size;
 177   pki.prime2()->assign(pos, pos + primes_size);
 178   pos += primes_size;
 179
 180   pki.exponent1()->assign(pos, pos + primes_size);
 181   pos += primes_size;
 182   pki.exponent2()->assign(pos, pos + primes_size);
 183   pos += primes_size;
 184
 185   pki.coefficient()->assign(pos, pos + primes_size);
 186   pos += primes_size;
 187
 188   pki.private_exponent()->assign(pos, pos + mod_size);
 189   pos += mod_size;
 190
 191   pki.public_exponent()->assign(reinterpret_cast<uint8*>(&rsa_pub_key->pubexp),
 192       reinterpret_cast<uint8*>(&rsa_pub_key->pubexp) + 4);
 193
 194   CHECK_EQ(pos - blob_length, reinterpret_cast<BYTE*>(publickey_struct));
 195
 196   return pki.Export(output);
 197 }
 198
 199 bool RSAPrivateKey::ExportPublicKey(std::vector<uint8>* output) const {
 200   DWORD key_info_len;
 201   if (!CryptExportPublicKeyInfo(
 202       provider_, AT_SIGNATURE, X509_ASN_ENCODING | PKCS_7_ASN_ENCODING,
 203       NULL, &key_info_len)) {
 204     NOTREACHED();
 205     return false;
 206   }
 207
 208   scoped_array<uint8> key_info(new uint8[key_info_len]);
 209   if (!CryptExportPublicKeyInfo(
 210       provider_, AT_SIGNATURE, X509_ASN_ENCODING | PKCS_7_ASN_ENCODING,
 211       reinterpret_cast<CERT_PUBLIC_KEY_INFO*>(key_info.get()), &key_info_len)) {
 212     NOTREACHED();
 213     return false;
 214   }
 215
 216   DWORD encoded_length;
 217   if (!CryptEncodeObject(
 218       X509_ASN_ENCODING | PKCS_7_ASN_ENCODING, X509_PUBLIC_KEY_INFO,
 219       reinterpret_cast<CERT_PUBLIC_KEY_INFO*>(key_info.get()), NULL,
 220       &encoded_length)) {
 221     NOTREACHED();
 222     return false;
 223   }
 224
 225   scoped_array<BYTE> encoded(new BYTE[encoded_length]);
 226   if (!CryptEncodeObject(
 227       X509_ASN_ENCODING | PKCS_7_ASN_ENCODING, X509_PUBLIC_KEY_INFO,
 228       reinterpret_cast<CERT_PUBLIC_KEY_INFO*>(key_info.get()), encoded.get(),
 229       &encoded_length)) {
 230     NOTREACHED();
 231     return false;
 232   }
 233
 234   output->assign(encoded.get(), encoded.get() + encoded_length);
 235   return true;
 236 }
 237
 238 }  // namespace crypto