blob: 1a060283892296079e6ba7d338c914d5839cd702 [file] [log] [blame]
// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "crypto/ec_private_key.h"
#include <openssl/ec.h>
#include <openssl/evp.h>
#include <openssl/pkcs12.h>
#include <openssl/x509.h>
#include "base/logging.h"
#include "base/memory/scoped_ptr.h"
#include "crypto/openssl_util.h"
#include "crypto/scoped_openssl_types.h"
namespace crypto {
namespace {
// Function pointer definition, for injecting the required key export function
// into ExportKeyWithBio, below. |bio| is a temporary memory BIO object, and
// |key| is a handle to the input key object. Return 1 on success, 0 otherwise.
// NOTE: Used with OpenSSL functions, which do not comply with the Chromium
// style guide, hence the unusual parameter placement / types.
typedef int (*ExportBioFunction)(BIO* bio, const void* key);
using ScopedPKCS8_PRIV_KEY_INFO =
ScopedOpenSSL<PKCS8_PRIV_KEY_INFO, PKCS8_PRIV_KEY_INFO_free>;
using ScopedX509_SIG = ScopedOpenSSL<X509_SIG, X509_SIG_free>;
// Helper to export |key| into |output| via the specified ExportBioFunction.
bool ExportKeyWithBio(const void* key,
ExportBioFunction export_fn,
std::vector<uint8>* output) {
if (!key)
return false;
ScopedBIO bio(BIO_new(BIO_s_mem()));
if (!bio.get())
return false;
if (!export_fn(bio.get(), key))
return false;
char* data = NULL;
long len = BIO_get_mem_data(bio.get(), &data);
if (!data || len < 0)
return false;
output->assign(data, data + len);
return true;
}
// Function pointer definition, for injecting the required key export function
// into ExportKey below. |key| is a pointer to the input key object,
// and |data| is either NULL, or the address of an 'unsigned char*' pointer
// that points to the start of the output buffer. The function must return
// the number of bytes required to export the data, or -1 in case of error.
typedef int (*ExportDataFunction)(const void* key, unsigned char** data);
// Helper to export |key| into |output| via the specified export function.
bool ExportKey(const void* key,
ExportDataFunction export_fn,
std::vector<uint8>* output) {
if (!key)
return false;
int data_len = export_fn(key, NULL);
if (data_len < 0)
return false;
output->resize(static_cast<size_t>(data_len));
unsigned char* data = &(*output)[0];
if (export_fn(key, &data) < 0)
return false;
return true;
}
} // namespace
ECPrivateKey::~ECPrivateKey() {
if (key_)
EVP_PKEY_free(key_);
}
ECPrivateKey* ECPrivateKey::Copy() const {
scoped_ptr<ECPrivateKey> copy(new ECPrivateKey);
if (key_)
copy->key_ = EVP_PKEY_up_ref(key_);
return copy.release();
}
// static
bool ECPrivateKey::IsSupported() { return true; }
// static
ECPrivateKey* ECPrivateKey::Create() {
OpenSSLErrStackTracer err_tracer(FROM_HERE);
ScopedEC_KEY ec_key(EC_KEY_new_by_curve_name(NID_X9_62_prime256v1));
if (!ec_key.get() || !EC_KEY_generate_key(ec_key.get()))
return NULL;
scoped_ptr<ECPrivateKey> result(new ECPrivateKey());
result->key_ = EVP_PKEY_new();
if (!result->key_ || !EVP_PKEY_set1_EC_KEY(result->key_, ec_key.get()))
return NULL;
CHECK_EQ(EVP_PKEY_EC, EVP_PKEY_type(result->key_->type));
return result.release();
}
// static
ECPrivateKey* ECPrivateKey::CreateFromEncryptedPrivateKeyInfo(
const std::string& password,
const std::vector<uint8>& encrypted_private_key_info,
const std::vector<uint8>& subject_public_key_info) {
// NOTE: The |subject_public_key_info| can be ignored here, it is only
// useful for the NSS implementation (which uses the public key's SHA1
// as a lookup key when storing the private one in its store).
if (encrypted_private_key_info.empty())
return NULL;
OpenSSLErrStackTracer err_tracer(FROM_HERE);
const uint8_t* data = &encrypted_private_key_info[0];
const uint8_t* ptr = data;
ScopedX509_SIG p8_encrypted(
d2i_X509_SIG(NULL, &ptr, encrypted_private_key_info.size()));
if (!p8_encrypted || ptr != data + encrypted_private_key_info.size())
return NULL;
ScopedPKCS8_PRIV_KEY_INFO p8_decrypted;
if (password.empty()) {
// Hack for reading keys generated by an older version of the OpenSSL
// code. OpenSSL used to use "\0\0" rather than the empty string because it
// would treat the password as an ASCII string to be converted to UCS-2
// while NSS used a byte string.
p8_decrypted.reset(PKCS8_decrypt_pbe(
p8_encrypted.get(), reinterpret_cast<const uint8_t*>("\0\0"), 2));
}
if (!p8_decrypted) {
p8_decrypted.reset(PKCS8_decrypt_pbe(
p8_encrypted.get(),
reinterpret_cast<const uint8_t*>(password.data()),
password.size()));
}
if (!p8_decrypted)
return NULL;
// Create a new EVP_PKEY for it.
scoped_ptr<ECPrivateKey> result(new ECPrivateKey);
result->key_ = EVP_PKCS82PKEY(p8_decrypted.get());
if (!result->key_ || EVP_PKEY_type(result->key_->type) != EVP_PKEY_EC)
return NULL;
return result.release();
}
bool ECPrivateKey::ExportEncryptedPrivateKey(
const std::string& password,
int iterations,
std::vector<uint8>* output) {
OpenSSLErrStackTracer err_tracer(FROM_HERE);
// Convert into a PKCS#8 object.
ScopedPKCS8_PRIV_KEY_INFO pkcs8(EVP_PKEY2PKCS8(key_));
if (!pkcs8.get())
return false;
// Encrypt the object.
// NOTE: NSS uses SEC_OID_PKCS12_V2_PBE_WITH_SHA1_AND_3KEY_TRIPLE_DES_CBC
// so use NID_pbe_WithSHA1And3_Key_TripleDES_CBC which should be the OpenSSL
// equivalent.
ScopedX509_SIG encrypted(PKCS8_encrypt_pbe(
NID_pbe_WithSHA1And3_Key_TripleDES_CBC,
nullptr,
reinterpret_cast<const uint8_t*>(password.data()),
password.size(),
nullptr,
0,
iterations,
pkcs8.get()));
if (!encrypted.get())
return false;
// Write it into |*output|
return ExportKeyWithBio(encrypted.get(),
reinterpret_cast<ExportBioFunction>(i2d_PKCS8_bio),
output);
}
bool ECPrivateKey::ExportPublicKey(std::vector<uint8>* output) {
OpenSSLErrStackTracer err_tracer(FROM_HERE);
return ExportKeyWithBio(
key_, reinterpret_cast<ExportBioFunction>(i2d_PUBKEY_bio), output);
}
bool ECPrivateKey::ExportRawPublicKey(std::string* output) {
// i2d_PublicKey will produce an ANSI X9.62 public key which, for a P-256
// key, is 0x04 (meaning uncompressed) followed by the x and y field
// elements as 32-byte, big-endian numbers.
static const int kExpectedKeyLength = 65;
int len = i2d_PublicKey(key_, NULL);
if (len != kExpectedKeyLength)
return false;
uint8 buf[kExpectedKeyLength];
uint8* derp = buf;
len = i2d_PublicKey(key_, &derp);
if (len != kExpectedKeyLength)
return false;
output->assign(reinterpret_cast<char*>(buf + 1), kExpectedKeyLength - 1);
return true;
}
bool ECPrivateKey::ExportValue(std::vector<uint8>* output) {
OpenSSLErrStackTracer err_tracer(FROM_HERE);
ScopedEC_KEY ec_key(EVP_PKEY_get1_EC_KEY(key_));
return ExportKey(ec_key.get(),
reinterpret_cast<ExportDataFunction>(i2d_ECPrivateKey),
output);
}
bool ECPrivateKey::ExportECParams(std::vector<uint8>* output) {
OpenSSLErrStackTracer err_tracer(FROM_HERE);
ScopedEC_KEY ec_key(EVP_PKEY_get1_EC_KEY(key_));
return ExportKey(ec_key.get(),
reinterpret_cast<ExportDataFunction>(i2d_ECParameters),
output);
}
ECPrivateKey::ECPrivateKey() : key_(NULL) {}
} // namespace crypto