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/ec_private_key.h" 6 7 #include <openssl/ec.h> 8 #include <openssl/evp.h> 9 #include <openssl/pkcs12.h> 10 #include <openssl/x509.h> 11 12 #include "base/logging.h" 13 #include "base/memory/scoped_ptr.h" 14 #include "crypto/openssl_util.h" 15 16 namespace crypto { 17 18 namespace { 19 20 // Function pointer definition, for injecting the required key export function 21 // into ExportKeyWithBio, below. |bio| is a temporary memory BIO object, and 22 // |key| is a handle to the input key object. Return 1 on success, 0 otherwise. 23 // NOTE: Used with OpenSSL functions, which do not comply with the Chromium 24 // style guide, hence the unusual parameter placement / types. 25 typedef int (*ExportBioFunction)(BIO* bio, const void* key); 26 27 // Helper to export |key| into |output| via the specified ExportBioFunction. 28 bool ExportKeyWithBio(const void* key, 29 ExportBioFunction export_fn, 30 std::vector<uint8>* output) { 31 if (!key) 32 return false; 33 34 ScopedOpenSSL<BIO, BIO_free_all> bio(BIO_new(BIO_s_mem())); 35 if (!bio.get()) 36 return false; 37 38 if (!export_fn(bio.get(), key)) 39 return false; 40 41 char* data = NULL; 42 long len = BIO_get_mem_data(bio.get(), &data); 43 if (!data || len < 0) 44 return false; 45 46 output->assign(data, data + len); 47 return true; 48 } 49 50 // Function pointer definition, for injecting the required key export function 51 // into ExportKey below. |key| is a pointer to the input key object, 52 // and |data| is either NULL, or the address of an 'unsigned char*' pointer 53 // that points to the start of the output buffer. The function must return 54 // the number of bytes required to export the data, or -1 in case of error. 55 typedef int (*ExportDataFunction)(const void* key, unsigned char** data); 56 57 // Helper to export |key| into |output| via the specified export function. 58 bool ExportKey(const void* key, 59 ExportDataFunction export_fn, 60 std::vector<uint8>* output) { 61 if (!key) 62 return false; 63 64 int data_len = export_fn(key, NULL); 65 if (data_len < 0) 66 return false; 67 68 output->resize(static_cast<size_t>(data_len)); 69 unsigned char* data = &(*output)[0]; 70 if (export_fn(key, &data) < 0) 71 return false; 72 73 return true; 74 } 75 76 } // namespace 77 78 ECPrivateKey::~ECPrivateKey() { 79 if (key_) 80 EVP_PKEY_free(key_); 81 } 82 83 // static 84 bool ECPrivateKey::IsSupported() { return true; } 85 86 // static 87 ECPrivateKey* ECPrivateKey::Create() { 88 OpenSSLErrStackTracer err_tracer(FROM_HERE); 89 90 ScopedOpenSSL<EC_KEY, EC_KEY_free> ec_key( 91 EC_KEY_new_by_curve_name(NID_X9_62_prime256v1)); 92 if (!ec_key.get() || !EC_KEY_generate_key(ec_key.get())) 93 return NULL; 94 95 scoped_ptr<ECPrivateKey> result(new ECPrivateKey()); 96 result->key_ = EVP_PKEY_new(); 97 if (!result->key_ || !EVP_PKEY_set1_EC_KEY(result->key_, ec_key.get())) 98 return NULL; 99 100 return result.release(); 101 } 102 103 // static 104 ECPrivateKey* ECPrivateKey::CreateFromEncryptedPrivateKeyInfo( 105 const std::string& password, 106 const std::vector<uint8>& encrypted_private_key_info, 107 const std::vector<uint8>& subject_public_key_info) { 108 // NOTE: The |subject_public_key_info| can be ignored here, it is only 109 // useful for the NSS implementation (which uses the public key's SHA1 110 // as a lookup key when storing the private one in its store). 111 if (encrypted_private_key_info.empty()) 112 return NULL; 113 114 OpenSSLErrStackTracer err_tracer(FROM_HERE); 115 // Write the encrypted private key into a memory BIO. 116 char* private_key_data = reinterpret_cast<char*>( 117 const_cast<uint8*>(&encrypted_private_key_info[0])); 118 int private_key_data_len = 119 static_cast<int>(encrypted_private_key_info.size()); 120 ScopedOpenSSL<BIO, BIO_free_all> bio( 121 BIO_new_mem_buf(private_key_data, private_key_data_len)); 122 if (!bio.get()) 123 return NULL; 124 125 // Convert it, then decrypt it into a PKCS#8 object. 126 ScopedOpenSSL<X509_SIG, X509_SIG_free> p8_encrypted( 127 d2i_PKCS8_bio(bio.get(), NULL)); 128 if (!p8_encrypted.get()) 129 return NULL; 130 131 ScopedOpenSSL<PKCS8_PRIV_KEY_INFO, PKCS8_PRIV_KEY_INFO_free> p8_decrypted( 132 PKCS8_decrypt(p8_encrypted.get(), 133 password.c_str(), 134 static_cast<int>(password.size()))); 135 if (!p8_decrypted.get() && password.empty()) { 136 // Hack for reading keys generated by ec_private_key_nss. Passing NULL 137 // causes OpenSSL to use an empty password instead of "\0\0". 138 p8_decrypted.reset(PKCS8_decrypt(p8_encrypted.get(), NULL, 0)); 139 } 140 if (!p8_decrypted.get()) 141 return NULL; 142 143 // Create a new EVP_PKEY for it. 144 scoped_ptr<ECPrivateKey> result(new ECPrivateKey); 145 result->key_ = EVP_PKCS82PKEY(p8_decrypted.get()); 146 if (!result->key_) 147 return NULL; 148 149 return result.release(); 150 } 151 152 bool ECPrivateKey::ExportEncryptedPrivateKey( 153 const std::string& password, 154 int iterations, 155 std::vector<uint8>* output) { 156 OpenSSLErrStackTracer err_tracer(FROM_HERE); 157 // Convert into a PKCS#8 object. 158 ScopedOpenSSL<PKCS8_PRIV_KEY_INFO, PKCS8_PRIV_KEY_INFO_free> pkcs8( 159 EVP_PKEY2PKCS8(key_)); 160 if (!pkcs8.get()) 161 return false; 162 163 // Encrypt the object. 164 // NOTE: NSS uses SEC_OID_PKCS12_V2_PBE_WITH_SHA1_AND_3KEY_TRIPLE_DES_CBC 165 // so use NID_pbe_WithSHA1And3_Key_TripleDES_CBC which should be the OpenSSL 166 // equivalent. 167 ScopedOpenSSL<X509_SIG, X509_SIG_free> encrypted( 168 PKCS8_encrypt(NID_pbe_WithSHA1And3_Key_TripleDES_CBC, 169 NULL, 170 password.c_str(), 171 static_cast<int>(password.size()), 172 NULL, 173 0, 174 iterations, 175 pkcs8.get())); 176 if (!encrypted.get()) 177 return false; 178 179 // Write it into |*output| 180 return ExportKeyWithBio(encrypted.get(), 181 reinterpret_cast<ExportBioFunction>(i2d_PKCS8_bio), 182 output); 183 } 184 185 bool ECPrivateKey::ExportPublicKey(std::vector<uint8>* output) { 186 OpenSSLErrStackTracer err_tracer(FROM_HERE); 187 return ExportKeyWithBio( 188 key_, reinterpret_cast<ExportBioFunction>(i2d_PUBKEY_bio), output); 189 } 190 191 bool ECPrivateKey::ExportValue(std::vector<uint8>* output) { 192 OpenSSLErrStackTracer err_tracer(FROM_HERE); 193 ScopedOpenSSL<EC_KEY, EC_KEY_free> ec_key(EVP_PKEY_get1_EC_KEY(key_)); 194 return ExportKey(ec_key.get(), 195 reinterpret_cast<ExportDataFunction>(i2d_ECPrivateKey), 196 output); 197 } 198 199 bool ECPrivateKey::ExportECParams(std::vector<uint8>* output) { 200 OpenSSLErrStackTracer err_tracer(FROM_HERE); 201 ScopedOpenSSL<EC_KEY, EC_KEY_free> ec_key(EVP_PKEY_get1_EC_KEY(key_)); 202 return ExportKey(ec_key.get(), 203 reinterpret_cast<ExportDataFunction>(i2d_ECParameters), 204 output); 205 } 206 207 ECPrivateKey::ECPrivateKey() : key_(NULL) {} 208 209 } // namespace crypto 210
