Example #1
0
result_t PKey::copy(const mbedtls_pk_context &key)
{
    mbedtls_pk_type_t type = mbedtls_pk_get_type(&key);
    int32_t ret;

    if (type == MBEDTLS_PK_RSA)
    {
        mbedtls_rsa_context *rsa = mbedtls_pk_rsa(key);

        ret = mbedtls_pk_setup(&m_key, mbedtls_pk_info_from_type(MBEDTLS_PK_RSA));
        if (ret != 0)
            return CHECK_ERROR(_ssl::setError(ret));

        mbedtls_rsa_context *rsa1 = mbedtls_pk_rsa(m_key);

        ret = mbedtls_rsa_copy(rsa1, rsa);
        if (ret != 0)
            return CHECK_ERROR(_ssl::setError(ret));

        return 0;
    }

    if (type == MBEDTLS_PK_ECKEY)
    {
        mbedtls_ecp_keypair *ecp = mbedtls_pk_ec(key);

        ret = mbedtls_pk_setup(&m_key, mbedtls_pk_info_from_type(MBEDTLS_PK_ECKEY));
        if (ret != 0)
            return CHECK_ERROR(_ssl::setError(ret));

        mbedtls_ecp_keypair *ecp1 = mbedtls_pk_ec(m_key);

        ret = mbedtls_ecp_group_copy(&ecp1->grp, &ecp->grp);
        if (ret != 0)
            return CHECK_ERROR(_ssl::setError(ret));

        ret = mbedtls_mpi_copy(&ecp1->d, &ecp->d);
        if (ret != 0)
            return CHECK_ERROR(_ssl::setError(ret));

        ret = mbedtls_ecp_copy(&ecp1->Q, &ecp->Q);
        if (ret != 0)
            return CHECK_ERROR(_ssl::setError(ret));

        return 0;
    }

    return CHECK_ERROR(CALL_E_INVALID_CALL);
}
Example #2
0
result_t PKey::genEcKey(const char *curve, AsyncEvent *ac)
{
    if (!ac)
        return CHECK_ERROR(CALL_E_NOSYNC);

    const mbedtls_ecp_curve_info *curve_info;
    curve_info = mbedtls_ecp_curve_info_from_name(curve);
    if (curve_info == NULL)
        return CHECK_ERROR(Runtime::setError("PKey: Unknown curve"));

    int32_t ret;

    clear();

    ret = mbedtls_pk_setup(&m_key, mbedtls_pk_info_from_type(MBEDTLS_PK_ECKEY));
    if (ret != 0)
        return CHECK_ERROR(_ssl::setError(ret));

    ret = mbedtls_ecp_gen_key(curve_info->grp_id, mbedtls_pk_ec(m_key),
                              mbedtls_ctr_drbg_random, &g_ssl.ctr_drbg);

    if (ret != 0)
        return CHECK_ERROR(_ssl::setError(ret));

    return 0;
}
Example #3
0
/*
 *  SubjectPublicKeyInfo  ::=  SEQUENCE  {
 *       algorithm            AlgorithmIdentifier,
 *       subjectPublicKey     BIT STRING }
 */
int mbedtls_pk_parse_subpubkey( unsigned char **p, const unsigned char *end,
                        mbedtls_pk_context *pk )
{
    int ret;
    size_t len;
    mbedtls_asn1_buf alg_params;
    mbedtls_pk_type_t pk_alg = MBEDTLS_PK_NONE;
    const mbedtls_pk_info_t *pk_info;

    if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
                    MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
    {
        return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT + ret );
    }

    end = *p + len;

    if( ( ret = pk_get_pk_alg( p, end, &pk_alg, &alg_params ) ) != 0 )
        return( ret );

    if( ( ret = mbedtls_asn1_get_bitstring_null( p, end, &len ) ) != 0 )
        return( MBEDTLS_ERR_PK_INVALID_PUBKEY + ret );

    if( *p + len != end )
        return( MBEDTLS_ERR_PK_INVALID_PUBKEY +
                MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );

    if( ( pk_info = mbedtls_pk_info_from_type( pk_alg ) ) == NULL )
        return( MBEDTLS_ERR_PK_UNKNOWN_PK_ALG );

    if( ( ret = mbedtls_pk_setup( pk, pk_info ) ) != 0 )
        return( ret );

#if defined(MBEDTLS_RSA_C)
    if( pk_alg == MBEDTLS_PK_RSA )
    {
        ret = pk_get_rsapubkey( p, end, mbedtls_pk_rsa( *pk ) );
    } else
#endif /* MBEDTLS_RSA_C */
#if defined(MBEDTLS_ECP_C)
    if( pk_alg == MBEDTLS_PK_ECKEY_DH || pk_alg == MBEDTLS_PK_ECKEY )
    {
        ret = pk_use_ecparams( &alg_params, &mbedtls_pk_ec( *pk )->grp );
        if( ret == 0 )
            ret = pk_get_ecpubkey( p, end, mbedtls_pk_ec( *pk ) );
    } else
#endif /* MBEDTLS_ECP_C */
        ret = MBEDTLS_ERR_PK_UNKNOWN_PK_ALG;

    if( ret == 0 && *p != end )
        ret = MBEDTLS_ERR_PK_INVALID_PUBKEY
              MBEDTLS_ERR_ASN1_LENGTH_MISMATCH;

    if( ret != 0 )
        mbedtls_pk_free( pk );

    return( ret );
}
int pki_privkey_build_rsa(ssh_key key,
                          ssh_string n,
                          ssh_string e,
                          ssh_string d,
                          ssh_string iqmp,
                          ssh_string p,
                          ssh_string q)
{
    mbedtls_rsa_context *rsa = NULL;
    const mbedtls_pk_info_t *pk_info = NULL;
    int rc;

    key->rsa = malloc(sizeof(mbedtls_pk_context));
    if (key->rsa == NULL) {
        return SSH_ERROR;
    }

    mbedtls_pk_init(key->rsa);
    pk_info = mbedtls_pk_info_from_type(MBEDTLS_PK_RSA);
    mbedtls_pk_setup(key->rsa, pk_info);

    rc = mbedtls_pk_can_do(key->rsa, MBEDTLS_PK_RSA);
    if (rc == 0) {
        goto fail;
    }

    rsa = mbedtls_pk_rsa(*key->rsa);
    rc = mbedtls_rsa_import_raw(rsa,
                                ssh_string_data(n), ssh_string_len(n),
                                ssh_string_data(p), ssh_string_len(p),
                                ssh_string_data(q), ssh_string_len(q),
                                ssh_string_data(d), ssh_string_len(d),
                                ssh_string_data(e), ssh_string_len(e));
    if (rc != 0) {
        SSH_LOG(SSH_LOG_WARN, "Failed to import private RSA key");
        goto fail;
    }

    rc = mbedtls_rsa_complete(rsa);
    if (rc != 0) {
        SSH_LOG(SSH_LOG_WARN, "Failed to complete private RSA key");
        goto fail;
    }

    rc = mbedtls_rsa_check_privkey(rsa);
    if (rc != 0) {
        SSH_LOG(SSH_LOG_WARN, "Inconsistent private RSA key");
        goto fail;
    }

    return SSH_OK;

fail:
    mbedtls_pk_free(key->rsa);
    SAFE_FREE(key->rsa);
    return SSH_ERROR;
}
Example #5
0
int extract_public_ec_key_length(uint8_t* buffer, size_t max_length, const uint8_t* private_key, size_t private_key_len)
{
	mbedtls_pk_context key;
	mbedtls_pk_init(&key);
	int error = mbedtls_pk_setup(&key, mbedtls_pk_info_from_type(MBEDTLS_PK_ECKEY));
	if (!error)
		error = mbedtls_pk_parse_key(&key, private_key, private_key_len, nullptr, 0);
	if (!error)
		error = mbedtls_pk_write_pubkey_der(&key, buffer, max_length);

	mbedtls_pk_free(&key);
	return error;
}
Example #6
0
/**
* Given the indirected identifier for the cipher algorithm return its label.
*
* @param Cipher The cipher algorithm in question.
* @return The label for the cipher.
*/
const char* get_cipher_label(Cipher c) {
  if (_is_cipher_symmetric(c)) {
    const mbedtls_cipher_info_t* info = mbedtls_cipher_info_from_type((mbedtls_cipher_type_t)c);
    if (info) {
      return info->name;
    }
  }
  else {
    const mbedtls_pk_info_t* info = mbedtls_pk_info_from_type((mbedtls_pk_type_t)c);
    if (info) {
      return info->name;
    }
  }
  return "<UNKNOWN>";
}
Example #7
0
/**
* Given the identifier for the cipher algorithm return the key size.
*
* @param Cipher The cipher algorithm in question.
* @return The size of the buffer (in bytes) required to hold the cipher key.
*/
int get_cipher_key_length(Cipher c) {
  if (_is_cipher_symmetric(c)) {
    const mbedtls_cipher_info_t* info = mbedtls_cipher_info_from_type((mbedtls_cipher_type_t)c);
    if (info) {
      return info->key_bitlen;
    }
  }
  else {
    const mbedtls_pk_info_t* info = mbedtls_pk_info_from_type((mbedtls_pk_type_t)c);
    if (info) {
      //return info->key_bitlen;
    }
    //mbedtls_pk_get_bitlen
  }
  return 0;
}
Example #8
0
int gen_ec_key(uint8_t* buffer, size_t max_length, int (*f_rng) (void *, uint8_t* buf, size_t len), void *p_rng)
{
	mbedtls_pk_context key;
	memset(&key, 0, sizeof(key));
	int error = mbedtls_pk_setup(&key, mbedtls_pk_info_from_type(MBEDTLS_PK_ECKEY));
	if (!error)
		error = mbedtls_ecp_gen_key(MBEDTLS_ECP_DP_SECP256R1, mbedtls_pk_ec(key), f_rng, p_rng );
	if (!error) {
		int result = mbedtls_pk_write_key_der(&key, buffer, max_length);
		if (result<0)
			error = result;
		else if (result>0)
		{
			// the key is written to the end of the buffer - align to the start
			memmove(buffer, buffer+max_length-result, result);
		}
	}
	mbedtls_pk_free(&key);
	return error;
}
Example #9
0
int mbedtls_ecies_write_originator(unsigned char **p, unsigned char *start,
        mbedtls_ecp_keypair *originator_keypair)
{
    int result = 0;
    size_t len = 0;
    mbedtls_pk_context pk;

    if (originator_keypair == NULL)
    {
        return MBEDTLS_ERR_ECIES_BAD_INPUT_DATA;
    }

    pk.pk_info = mbedtls_pk_info_from_type(MBEDTLS_PK_ECKEY);
    pk.pk_ctx = originator_keypair;
    ACCUMULATE_AND_CHECK(result, len,
        mbedtls_pk_write_pubkey_der(&pk, start , *p - start)
    );
    *p -= len;
    return (int)len;
}
Example #10
0
int pki_pubkey_build_rsa(ssh_key key, ssh_string e, ssh_string n)
{
    mbedtls_rsa_context *rsa = NULL;
    const mbedtls_pk_info_t *pk_info = NULL;
    int rc;

    key->rsa = malloc(sizeof(mbedtls_pk_context));
    if (key->rsa == NULL) {
        return SSH_ERROR;
    }

    mbedtls_pk_init(key->rsa);
    pk_info = mbedtls_pk_info_from_type(MBEDTLS_PK_RSA);
    mbedtls_pk_setup(key->rsa, pk_info);

    rc = mbedtls_pk_can_do(key->rsa, MBEDTLS_PK_RSA);
    if (rc == 0) {
        goto fail;
    }

    rsa = mbedtls_pk_rsa(*key->rsa);
    rc = mbedtls_mpi_read_binary(&rsa->N, ssh_string_data(n),
                                 ssh_string_len(n));
    if (rc != 0) {
        goto fail;
    }
    rc = mbedtls_mpi_read_binary(&rsa->E, ssh_string_data(e),
                                 ssh_string_len(e));
    if (rc != 0) {
        goto fail;
    }

    rsa->len = (mbedtls_mpi_bitlen(&rsa->N) + 7) >> 3;

    return SSH_OK;

fail:
    mbedtls_pk_free(key->rsa);
    SAFE_FREE(key->rsa);
    return SSH_ERROR;
}
Example #11
0
result_t PKey::genRsaKey(int32_t size, AsyncEvent *ac)
{
    if (size < 128 || size > 8192)
        return CHECK_ERROR(Runtime::setError("PKey: Invalid key size"));

    if (!ac)
        return CHECK_ERROR(CALL_E_NOSYNC);

    int32_t ret;

    clear();

    ret = mbedtls_pk_setup(&m_key, mbedtls_pk_info_from_type(MBEDTLS_PK_RSA));
    if (ret != 0)
        return CHECK_ERROR(_ssl::setError(ret));

    ret = mbedtls_rsa_gen_key(mbedtls_pk_rsa(m_key), mbedtls_ctr_drbg_random,
                              &g_ssl.ctr_drbg, size, 65537);

    if (ret != 0)
        return CHECK_ERROR(_ssl::setError(ret));

    return 0;
}
Example #12
0
TEE_Result crypto_acipher_ecc_sign(uint32_t algo, struct ecc_keypair *key,
				   const uint8_t *msg, size_t msg_len,
				   uint8_t *sig, size_t *sig_len)
{
	TEE_Result res = TEE_SUCCESS;
	int lmd_res = 0;
	const mbedtls_pk_info_t *pk_info = NULL;
	mbedtls_ecdsa_context ecdsa;
	size_t key_size_bytes = 0;
	size_t key_size_bits = 0;
	mbedtls_mpi r;
	mbedtls_mpi s;

	memset(&ecdsa, 0, sizeof(ecdsa));
	memset(&r, 0, sizeof(r));
	memset(&s, 0, sizeof(s));

	if (algo == 0)
		return TEE_ERROR_BAD_PARAMETERS;

	mbedtls_mpi_init(&r);
	mbedtls_mpi_init(&s);

	mbedtls_ecdsa_init(&ecdsa);
	lmd_res = mbedtls_ecp_group_load(&ecdsa.grp, key->curve);
	if (lmd_res != 0) {
		res = TEE_ERROR_NOT_SUPPORTED;
		goto out;
	}

	ecdsa.d = *(mbedtls_mpi *)key->d;

	res = ecc_get_keysize(key->curve, algo, &key_size_bytes,
			      &key_size_bits);
	if (res != TEE_SUCCESS)
		goto out;

	pk_info = mbedtls_pk_info_from_type(MBEDTLS_PK_ECDSA);
	if (pk_info == NULL) {
		res = TEE_ERROR_NOT_SUPPORTED;
		goto out;
	}

	lmd_res = mbedtls_ecdsa_sign(&ecdsa.grp, &r, &s, &ecdsa.d, msg,
				     msg_len, mbd_rand, NULL);
	if (lmd_res == 0) {
		*sig_len = 2 * key_size_bytes;
		memset(sig, 0, *sig_len);
		mbedtls_mpi_write_binary(&r, sig + *sig_len / 2 -
					 mbedtls_mpi_size(&r),
					 mbedtls_mpi_size(&r));

		mbedtls_mpi_write_binary(&s, sig + *sig_len -
					 mbedtls_mpi_size(&s),
					 mbedtls_mpi_size(&s));
		res = TEE_SUCCESS;
	} else {
		FMSG("mbedtls_ecdsa_sign failed, returned 0x%x\n", -lmd_res);
		res = TEE_ERROR_GENERIC;
	}
out:
	mbedtls_mpi_free(&r);
	mbedtls_mpi_free(&s);
	/* Reset mpi to skip freeing here, those mpis will be freed with key */
	mbedtls_mpi_init(&ecdsa.d);
	mbedtls_ecdsa_free(&ecdsa);
	return res;
}
Example #13
0
/*******************************************************************************
* Asymmetric ciphers                                                           *
*******************************************************************************/
int __attribute__((weak)) wrapped_asym_keygen(Cipher c, CryptoKey key_type, uint8_t* pub, size_t* pub_len, uint8_t* priv, size_t* priv_len) {
  if (keygen_deferred_handling(key_type)) {
    // If overriden by user implementation.
    return _keygen_overrides[key_type](c, key_type, pub, pub_len, priv, priv_len);
  }
  int ret = -1;

  mbedtls_pk_context key;
  mbedtls_pk_init(&key);

  uint32_t pers = randomInt();
  mbedtls_ctr_drbg_context ctr_drbg;
  mbedtls_ctr_drbg_init(&ctr_drbg);
  ret = mbedtls_ctr_drbg_seed(
    &ctr_drbg, mbedtls_entropy_func, &entropy,
    (const uint8_t*) &pers, 4
  );
  if (0 == ret) {
    switch (c) {
      #if defined(WRAPPED_ASYM_RSA)
        case Cipher::ASYM_RSA:
          {
            ret = mbedtls_pk_setup(&key, mbedtls_pk_info_from_type(MBEDTLS_PK_RSA));
            if (0 == ret) {
              mbedtls_rsa_context* rsa = mbedtls_pk_rsa(key);
              ret = mbedtls_rsa_gen_key(rsa,
                mbedtls_ctr_drbg_random, &ctr_drbg,
                (int) key_type, 65537
              );
              if (0 == ret) {
                ret--;
                memset(pub,  0, *pub_len);
                memset(priv, 0, *priv_len);
                int written = mbedtls_pk_write_pubkey_der(&key, pub, *pub_len);
                if (0 < written) {
                  *pub_len = written;
                  written = mbedtls_pk_write_key_der(&key, priv, *priv_len);
                  if (0 < written) {
                    *priv_len = written;
                    ret = 0;
                  }
                }
              }
            }
          }
          break;
      #endif
      #if defined(MBEDTLS_ECDSA_C)
        case Cipher::ASYM_ECDSA:
          {
            ret = mbedtls_pk_setup(&key, mbedtls_pk_info_from_type(MBEDTLS_PK_ECKEY));
            if (0 == ret) {
              mbedtls_ecp_keypair* ec_kp = mbedtls_pk_ec(key);
              ret = mbedtls_ecdsa_genkey(ec_kp,
                (mbedtls_ecp_group_id) key_type,
                mbedtls_ctr_drbg_random, &ctr_drbg
              );
              if (0 == ret) {
                ret--;
                memset(pub,  0, *pub_len);
                memset(priv, 0, *priv_len);
                int written = mbedtls_pk_write_pubkey_der(&key, pub, *pub_len);
                if (0 < written) {
                  *pub_len = written;
                  written = mbedtls_pk_write_key_der(&key, priv, *priv_len);
                  if (0 < written) {
                    *priv_len = written;
                    ret = 0;
                  }
                }
              }
            }
          }
          break;
      #endif
      #if defined(MBEDTLS_ECP_C)
        case Cipher::ASYM_ECKEY:
          {
            ret = mbedtls_pk_setup(&key, mbedtls_pk_info_from_type(MBEDTLS_PK_ECKEY));
            if (0 == ret) {
              mbedtls_ecp_keypair* ec_kp = mbedtls_pk_ec(key);
              ret = mbedtls_ecp_gen_key(
                (mbedtls_ecp_group_id) key_type,
                ec_kp,
                mbedtls_ctr_drbg_random, &ctr_drbg
              );
              if (0 == ret) {
                ret--;
                memset(pub,  0, *pub_len);
                memset(priv, 0, *priv_len);
                int written = mbedtls_pk_write_pubkey_der(&key, pub, *pub_len);
                if (0 < written) {
                  *pub_len = written;
                  written = mbedtls_pk_write_key_der(&key, priv, *priv_len);
                  if (0 < written) {
                    *priv_len = written;
                    ret = 0;
                  }
                }
              }
            }
          }
          break;
      #endif
      default:
        break;
    }
  }
  mbedtls_pk_free(&key);
  mbedtls_ctr_drbg_free(&ctr_drbg);
  return ret;
}
Example #14
0
result_t PKey::get_publicKey(obj_ptr<PKey_base> &retVal)
{
    result_t hr;
    bool priv;

    hr = isPrivate(priv);
    if (hr < 0)
        return hr;

    if (!priv)
        return CALL_RETURN_NULL;

    mbedtls_pk_type_t type = mbedtls_pk_get_type(&m_key);
    int32_t ret;

    if (type == MBEDTLS_PK_RSA)
    {
        mbedtls_rsa_context *rsa = mbedtls_pk_rsa(m_key);
        obj_ptr<PKey> pk1 = new PKey();

        ret = mbedtls_pk_setup(&pk1->m_key, mbedtls_pk_info_from_type(MBEDTLS_PK_RSA));
        if (ret != 0)
            return CHECK_ERROR(_ssl::setError(ret));

        mbedtls_rsa_context *rsa1 = mbedtls_pk_rsa(pk1->m_key);

        rsa1->len = rsa->len;
        rsa1->padding = rsa->padding;
        rsa1->hash_id = rsa->hash_id;

        ret = mbedtls_mpi_copy(&rsa1->N, &rsa->N);
        if (ret != 0)
            return CHECK_ERROR(_ssl::setError(ret));

        ret = mbedtls_mpi_copy(&rsa1->E, &rsa->E);
        if (ret != 0)
            return CHECK_ERROR(_ssl::setError(ret));

        retVal = pk1;

        return 0;
    }

    if (type == MBEDTLS_PK_ECKEY)
    {
        mbedtls_ecp_keypair *ecp = mbedtls_pk_ec(m_key);

        obj_ptr<PKey> pk1 = new PKey();

        ret = mbedtls_pk_setup(&pk1->m_key, mbedtls_pk_info_from_type(MBEDTLS_PK_ECKEY));
        if (ret != 0)
            return CHECK_ERROR(_ssl::setError(ret));

        mbedtls_ecp_keypair *ecp1 = mbedtls_pk_ec(pk1->m_key);

        ret = mbedtls_ecp_group_copy(&ecp1->grp, &ecp->grp);
        if (ret != 0)
            return CHECK_ERROR(_ssl::setError(ret));

        ret = mbedtls_ecp_copy(&ecp1->Q, &ecp->Q);
        if (ret != 0)
            return CHECK_ERROR(_ssl::setError(ret));

        retVal = pk1;

        return 0;
    }

    return CHECK_ERROR(CALL_E_INVALID_CALL);
}
Example #15
0
/**
* Wrapper for sign-verify operations.
*
* @param Cipher     Algorithm class
* @param CryptoKey  Key parameters
* @param Hashes     Digest alg to use.
* @param uint8_t*   Buffer to be signed/verified...
* @param int        ...and its length.
* @param uint8_t*   Buffer to hold signature...
* @param int*       ...and its length.
* @param uint8_t*   Buffer holding the key...
* @param int        ...and its length.
* @param uint32_t   Options to the operations.
* @return 0 if the operation completed successfully.
*/
int __attribute__((weak)) wrapped_sign_verify(Cipher c, CryptoKey k, Hashes h, uint8_t* msg, int msg_len, uint8_t* sig, size_t* sig_len, uint8_t* key, int key_len, uint32_t opts) {
  if (keygen_deferred_handling(k)) {
    // If overriden by user implementation.
    return _s_v_overrides[k](c, k, h, msg, msg_len, sig, sig_len, key, key_len, opts);
  }
  int ret = -1;   // Failure by default.

  uint8_t* hash;
  int hashlen;
  if (Hashes::NONE != h) {
    hashlen = get_digest_output_length(h);
    hash    = (uint8_t*) alloca(hashlen);
    if (hash) {
      ret = wrapped_hash(msg, msg_len, hash, h);
    }
  }
  else {
    // This is the no-digest case.
    hashlen = msg_len;
    hash    = msg;
    ret     = 0;   // TODO: Fail if size is greater than the maximum input length for the Key type.
  }

  if (0 == ret) {
    // If we are here, the hashing operation worked. Now we case-off on key/algo.
    mbedtls_pk_context k_ctx;
    mbedtls_pk_init(&k_ctx);
    uint32_t pers = randomInt();
    mbedtls_ctr_drbg_context ctr_drbg;
    mbedtls_ctr_drbg_init(&ctr_drbg);
    ret = mbedtls_ctr_drbg_seed(
      &ctr_drbg, mbedtls_entropy_func, &entropy,
      (const uint8_t*) &pers, 4
    );
    if (0 == ret) {
      switch (c) {
        #if defined(WRAPPED_ASYM_RSA)
          case Cipher::ASYM_RSA:
            //ret = mbedtls_pk_setup(&k_ctx, mbedtls_pk_info_from_type(MBEDTLS_PK_RSA));
            if (opts & OP_SIGN) {
              ret = mbedtls_pk_setup(&k_ctx, mbedtls_pk_info_from_type(MBEDTLS_PK_RSA));
              if (0 == ret) {
                ret = mbedtls_pk_parse_key(&k_ctx, key, key_len, nullptr, 0);
                if (0 == ret) {
                  ret = mbedtls_pk_sign(
                    &k_ctx,
                    (mbedtls_md_type_t) h, hash, hashlen,
                    sig, sig_len,
                    mbedtls_ctr_drbg_random, &ctr_drbg
                  );
                }
              }
            }
            else {
              ret = mbedtls_pk_parse_public_key(&k_ctx, key, key_len);
              if (0 == ret) {
                ret = mbedtls_pk_verify(
                  &k_ctx,
                  (mbedtls_md_type_t) h, hash, hashlen,
                  sig, *sig_len
                );
              }
            }
            break;
        #endif
        #if defined(MBEDTLS_ECDSA_C)
          case Cipher::ASYM_ECDSA:
            if (opts & OP_SIGN) {
              ret = mbedtls_pk_setup(&k_ctx, mbedtls_pk_info_from_type(MBEDTLS_PK_ECDSA));
              if (0 == ret) {
                ret = mbedtls_pk_parse_key(&k_ctx, key, key_len, nullptr, 0);
                if (0 == ret) {
                  ret = mbedtls_pk_sign(
                    &k_ctx,
                    (mbedtls_md_type_t) h, hash, hashlen,
                    sig, sig_len,
                    mbedtls_ctr_drbg_random, &ctr_drbg
                  );
                }
              }
            }
            else {
              ret = mbedtls_pk_parse_public_key(&k_ctx, key, key_len);
              if (0 == ret) {
                ret = mbedtls_pk_verify(
                  &k_ctx,
                  (mbedtls_md_type_t) h, hash, hashlen,
                  sig, *sig_len
                );
              }
            }
            break;
        #endif
        #if defined(MBEDTLS_ECP_C)
          case Cipher::ASYM_ECKEY:
            if (opts & OP_SIGN) {
              ret = mbedtls_pk_setup(&k_ctx, mbedtls_pk_info_from_type(MBEDTLS_PK_ECKEY));
              if (0 == ret) {
                ret = mbedtls_pk_parse_key(&k_ctx, key, key_len, nullptr, 0);
                if (0 == ret) {
                  ret = mbedtls_pk_sign(
                    &k_ctx,
                    (mbedtls_md_type_t) h, hash, hashlen,
                    sig, sig_len,
                    mbedtls_ctr_drbg_random, &ctr_drbg
                  );
                }
              }
            }
            else {
              ret = mbedtls_pk_parse_public_key(&k_ctx, key, key_len);
              if (0 == ret) {
                ret = mbedtls_pk_verify(
                  &k_ctx,
                  (mbedtls_md_type_t) h, hash, hashlen,
                  sig, *sig_len
                );
              }
            }
            break;
        #endif
        default:
          break;
      }
    }
  }

  return ret;
}
Example #16
0
/*
 * Parse a private key
 */
int mbedtls_pk_parse_key( mbedtls_pk_context *pk,
                  const unsigned char *key, size_t keylen,
                  const unsigned char *pwd, size_t pwdlen )
{
    int ret;
    const mbedtls_pk_info_t *pk_info;

#if defined(MBEDTLS_PEM_PARSE_C)
    size_t len;
    mbedtls_pem_context pem;

    mbedtls_pem_init( &pem );

#if defined(MBEDTLS_RSA_C)
    /* Avoid calling mbedtls_pem_read_buffer() on non-null-terminated string */
    if( keylen == 0 || key[keylen - 1] != '\0' )
        ret = MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT;
    else
        ret = mbedtls_pem_read_buffer( &pem,
                               "-----BEGIN RSA PRIVATE KEY-----",
                               "-----END RSA PRIVATE KEY-----",
                               key, pwd, pwdlen, &len );

    if( ret == 0 )
    {
        if( ( pk_info = mbedtls_pk_info_from_type( MBEDTLS_PK_RSA ) ) == NULL )
            return( MBEDTLS_ERR_PK_UNKNOWN_PK_ALG );

        if( ( ret = mbedtls_pk_setup( pk, pk_info                    ) ) != 0 ||
            ( ret = pk_parse_key_pkcs1_der( mbedtls_pk_rsa( *pk ),
                                            pem.buf, pem.buflen ) ) != 0 )
        {
            mbedtls_pk_free( pk );
        }

        mbedtls_pem_free( &pem );
        return( ret );
    }
    else if( ret == MBEDTLS_ERR_PEM_PASSWORD_MISMATCH )
        return( MBEDTLS_ERR_PK_PASSWORD_MISMATCH );
    else if( ret == MBEDTLS_ERR_PEM_PASSWORD_REQUIRED )
        return( MBEDTLS_ERR_PK_PASSWORD_REQUIRED );
    else if( ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT )
        return( ret );
#endif /* MBEDTLS_RSA_C */

#if defined(MBEDTLS_ECP_C)
    /* Avoid calling mbedtls_pem_read_buffer() on non-null-terminated string */
    if( keylen == 0 || key[keylen - 1] != '\0' )
        ret = MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT;
    else
        ret = mbedtls_pem_read_buffer( &pem,
                               "-----BEGIN EC PRIVATE KEY-----",
                               "-----END EC PRIVATE KEY-----",
                               key, pwd, pwdlen, &len );
    if( ret == 0 )
    {
        if( ( pk_info = mbedtls_pk_info_from_type( MBEDTLS_PK_ECKEY ) ) == NULL )
            return( MBEDTLS_ERR_PK_UNKNOWN_PK_ALG );

        if( ( ret = mbedtls_pk_setup( pk, pk_info                   ) ) != 0 ||
            ( ret = pk_parse_key_sec1_der( mbedtls_pk_ec( *pk ),
                                           pem.buf, pem.buflen ) ) != 0 )
        {
            mbedtls_pk_free( pk );
        }

        mbedtls_pem_free( &pem );
        return( ret );
    }
    else if( ret == MBEDTLS_ERR_PEM_PASSWORD_MISMATCH )
        return( MBEDTLS_ERR_PK_PASSWORD_MISMATCH );
    else if( ret == MBEDTLS_ERR_PEM_PASSWORD_REQUIRED )
        return( MBEDTLS_ERR_PK_PASSWORD_REQUIRED );
    else if( ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT )
        return( ret );
#endif /* MBEDTLS_ECP_C */

    /* Avoid calling mbedtls_pem_read_buffer() on non-null-terminated string */
    if( keylen == 0 || key[keylen - 1] != '\0' )
        ret = MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT;
    else
        ret = mbedtls_pem_read_buffer( &pem,
                               "-----BEGIN PRIVATE KEY-----",
                               "-----END PRIVATE KEY-----",
                               key, NULL, 0, &len );
    if( ret == 0 )
    {
        if( ( ret = pk_parse_key_pkcs8_unencrypted_der( pk,
                                                pem.buf, pem.buflen ) ) != 0 )
        {
            mbedtls_pk_free( pk );
        }

        mbedtls_pem_free( &pem );
        return( ret );
    }
    else if( ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT )
        return( ret );

#if defined(MBEDTLS_PKCS12_C) || defined(MBEDTLS_PKCS5_C)
    /* Avoid calling mbedtls_pem_read_buffer() on non-null-terminated string */
    if( keylen == 0 || key[keylen - 1] != '\0' )
        ret = MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT;
    else
        ret = mbedtls_pem_read_buffer( &pem,
                               "-----BEGIN ENCRYPTED PRIVATE KEY-----",
                               "-----END ENCRYPTED PRIVATE KEY-----",
                               key, NULL, 0, &len );
    if( ret == 0 )
    {
        if( ( ret = pk_parse_key_pkcs8_encrypted_der( pk,
                                                      pem.buf, pem.buflen,
                                                      pwd, pwdlen ) ) != 0 )
        {
            mbedtls_pk_free( pk );
        }

        mbedtls_pem_free( &pem );
        return( ret );
    }
    else if( ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT )
        return( ret );
#endif /* MBEDTLS_PKCS12_C || MBEDTLS_PKCS5_C */
#else
    ((void) ret);
    ((void) pwd);
    ((void) pwdlen);
#endif /* MBEDTLS_PEM_PARSE_C */

    /*
     * At this point we only know it's not a PEM formatted key. Could be any
     * of the known DER encoded private key formats
     *
     * We try the different DER format parsers to see if one passes without
     * error
     */
#if defined(MBEDTLS_PKCS12_C) || defined(MBEDTLS_PKCS5_C)
    if( ( ret = pk_parse_key_pkcs8_encrypted_der( pk, key, keylen,
                                                  pwd, pwdlen ) ) == 0 )
    {
        return( 0 );
    }

    mbedtls_pk_free( pk );

    if( ret == MBEDTLS_ERR_PK_PASSWORD_MISMATCH )
    {
        return( ret );
    }
#endif /* MBEDTLS_PKCS12_C || MBEDTLS_PKCS5_C */

    if( ( ret = pk_parse_key_pkcs8_unencrypted_der( pk, key, keylen ) ) == 0 )
        return( 0 );

    mbedtls_pk_free( pk );

#if defined(MBEDTLS_RSA_C)
    if( ( pk_info = mbedtls_pk_info_from_type( MBEDTLS_PK_RSA ) ) == NULL )
        return( MBEDTLS_ERR_PK_UNKNOWN_PK_ALG );

    if( ( ret = mbedtls_pk_setup( pk, pk_info                           ) ) != 0 ||
        ( ret = pk_parse_key_pkcs1_der( mbedtls_pk_rsa( *pk ), key, keylen ) ) == 0 )
    {
        return( 0 );
    }

    mbedtls_pk_free( pk );
#endif /* MBEDTLS_RSA_C */

#if defined(MBEDTLS_ECP_C)
    if( ( pk_info = mbedtls_pk_info_from_type( MBEDTLS_PK_ECKEY ) ) == NULL )
        return( MBEDTLS_ERR_PK_UNKNOWN_PK_ALG );

    if( ( ret = mbedtls_pk_setup( pk, pk_info                         ) ) != 0 ||
        ( ret = pk_parse_key_sec1_der( mbedtls_pk_ec( *pk ), key, keylen ) ) == 0 )
    {
        return( 0 );
    }

    mbedtls_pk_free( pk );
#endif /* MBEDTLS_ECP_C */

    return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT );
}
Example #17
0
int main( int argc, char *argv[] )
{
    int ret = 0;
    mbedtls_pk_context key;
    char buf[1024];
    int i;
    char *p, *q;
    mbedtls_entropy_context entropy;
    mbedtls_ctr_drbg_context ctr_drbg;
    const char *pers = "gen_key";
#if defined(MBEDTLS_ECP_C)
    const mbedtls_ecp_curve_info *curve_info;
#endif

    /*
     * Set to sane values
     */
    mbedtls_pk_init( &key );
    mbedtls_ctr_drbg_init( &ctr_drbg );
    memset( buf, 0, sizeof( buf ) );

    if( argc == 0 )
    {
    usage:
        ret = 1;
        mbedtls_printf( USAGE );
#if defined(MBEDTLS_ECP_C)
        mbedtls_printf( " available ec_curve values:\n" );
        curve_info = mbedtls_ecp_curve_list();
        mbedtls_printf( "    %s (default)\n", curve_info->name );
        while( ( ++curve_info )->name != NULL )
            mbedtls_printf( "    %s\n", curve_info->name );
#endif
        goto exit;
    }

    opt.type                = DFL_TYPE;
    opt.rsa_keysize         = DFL_RSA_KEYSIZE;
    opt.ec_curve            = DFL_EC_CURVE;
    opt.filename            = DFL_FILENAME;
    opt.format              = DFL_FORMAT;
    opt.use_dev_random      = DFL_USE_DEV_RANDOM;

    for( i = 1; i < argc; i++ )
    {
        p = argv[i];
        if( ( q = strchr( p, '=' ) ) == NULL )
            goto usage;
        *q++ = '\0';

        if( strcmp( p, "type" ) == 0 )
        {
            if( strcmp( q, "rsa" ) == 0 )
                opt.type = MBEDTLS_PK_RSA;
            else if( strcmp( q, "ec" ) == 0 )
                opt.type = MBEDTLS_PK_ECKEY;
            else
                goto usage;
        }
        else if( strcmp( p, "format" ) == 0 )
        {
            if( strcmp( q, "pem" ) == 0 )
                opt.format = FORMAT_PEM;
            else if( strcmp( q, "der" ) == 0 )
                opt.format = FORMAT_DER;
            else
                goto usage;
        }
        else if( strcmp( p, "rsa_keysize" ) == 0 )
        {
            opt.rsa_keysize = atoi( q );
            if( opt.rsa_keysize < 1024 ||
                opt.rsa_keysize > MBEDTLS_MPI_MAX_BITS )
                goto usage;
        }
#if defined(MBEDTLS_ECP_C)
        else if( strcmp( p, "ec_curve" ) == 0 )
        {
            if( ( curve_info = mbedtls_ecp_curve_info_from_name( q ) ) == NULL )
                goto usage;
            opt.ec_curve = curve_info->grp_id;
        }
#endif
        else if( strcmp( p, "filename" ) == 0 )
            opt.filename = q;
        else if( strcmp( p, "use_dev_random" ) == 0 )
        {
            opt.use_dev_random = atoi( q );
            if( opt.use_dev_random < 0 || opt.use_dev_random > 1 )
                goto usage;
        }
        else
            goto usage;
    }

    mbedtls_printf( "\n  . Seeding the random number generator..." );
    fflush( stdout );

    mbedtls_entropy_init( &entropy );
#if !defined(_WIN32) && defined(MBEDTLS_FS_IO)
    if( opt.use_dev_random )
    {
        if( ( ret = mbedtls_entropy_add_source( &entropy, dev_random_entropy_poll,
                                        NULL, DEV_RANDOM_THRESHOLD,
                                        MBEDTLS_ENTROPY_SOURCE_STRONG ) ) != 0 )
        {
            mbedtls_printf( " failed\n  ! mbedtls_entropy_add_source returned -0x%04x\n", -ret );
            goto exit;
        }

        mbedtls_printf("\n    Using /dev/random, so can take a long time! " );
        fflush( stdout );
    }
#endif /* !_WIN32 && MBEDTLS_FS_IO */

    if( ( ret = mbedtls_ctr_drbg_seed( &ctr_drbg, mbedtls_entropy_func, &entropy,
                               (const unsigned char *) pers,
                               strlen( pers ) ) ) != 0 )
    {
        mbedtls_printf( " failed\n  ! mbedtls_ctr_drbg_seed returned -0x%04x\n", -ret );
        goto exit;
    }

    /*
     * 1.1. Generate the key
     */
    mbedtls_printf( "\n  . Generating the private key ..." );
    fflush( stdout );

    if( ( ret = mbedtls_pk_setup( &key, mbedtls_pk_info_from_type( opt.type ) ) ) != 0 )
    {
        mbedtls_printf( " failed\n  !  mbedtls_pk_setup returned -0x%04x", -ret );
        goto exit;
    }

#if defined(MBEDTLS_RSA_C) && defined(MBEDTLS_GENPRIME)
    if( opt.type == MBEDTLS_PK_RSA )
    {
        ret = mbedtls_rsa_gen_key( mbedtls_pk_rsa( key ), mbedtls_ctr_drbg_random, &ctr_drbg,
                           opt.rsa_keysize, 65537 );
        if( ret != 0 )
        {
            mbedtls_printf( " failed\n  !  mbedtls_rsa_gen_key returned -0x%04x", -ret );
            goto exit;
        }
    }
    else
#endif /* MBEDTLS_RSA_C */
#if defined(MBEDTLS_ECP_C)
    if( opt.type == MBEDTLS_PK_ECKEY )
    {
        ret = mbedtls_ecp_gen_key( opt.ec_curve, mbedtls_pk_ec( key ),
                          mbedtls_ctr_drbg_random, &ctr_drbg );
        if( ret != 0 )
        {
            mbedtls_printf( " failed\n  !  mbedtls_rsa_gen_key returned -0x%04x", -ret );
            goto exit;
        }
    }
    else
#endif /* MBEDTLS_ECP_C */
    {
        mbedtls_printf( " failed\n  !  key type not supported\n" );
        goto exit;
    }

    /*
     * 1.2 Print the key
     */
    mbedtls_printf( " ok\n  . Key information:\n" );

#if defined(MBEDTLS_RSA_C)
    if( mbedtls_pk_get_type( &key ) == MBEDTLS_PK_RSA )
    {
        mbedtls_rsa_context *rsa = mbedtls_pk_rsa( key );
        mbedtls_mpi_write_file( "N:  ",  &rsa->N,  16, NULL );
        mbedtls_mpi_write_file( "E:  ",  &rsa->E,  16, NULL );
        mbedtls_mpi_write_file( "D:  ",  &rsa->D,  16, NULL );
        mbedtls_mpi_write_file( "P:  ",  &rsa->P,  16, NULL );
        mbedtls_mpi_write_file( "Q:  ",  &rsa->Q,  16, NULL );
        mbedtls_mpi_write_file( "DP: ",  &rsa->DP, 16, NULL );
        mbedtls_mpi_write_file( "DQ:  ", &rsa->DQ, 16, NULL );
        mbedtls_mpi_write_file( "QP:  ", &rsa->QP, 16, NULL );
    }
    else
#endif
#if defined(MBEDTLS_ECP_C)
    if( mbedtls_pk_get_type( &key ) == MBEDTLS_PK_ECKEY )
    {
        mbedtls_ecp_keypair *ecp = mbedtls_pk_ec( key );
        mbedtls_printf( "curve: %s\n",
                mbedtls_ecp_curve_info_from_grp_id( ecp->grp.id )->name );
        mbedtls_mpi_write_file( "X_Q:   ", &ecp->Q.X, 16, NULL );
        mbedtls_mpi_write_file( "Y_Q:   ", &ecp->Q.Y, 16, NULL );
        mbedtls_mpi_write_file( "D:     ", &ecp->d  , 16, NULL );
    }
    else
#endif
        mbedtls_printf("  ! key type not supported\n");

    /*
     * 1.3 Export key
     */
    mbedtls_printf( "  . Writing key to file..." );

    if( ( ret = write_private_key( &key, opt.filename ) ) != 0 )
    {
        mbedtls_printf( " failed\n" );
        goto exit;
    }

    mbedtls_printf( " ok\n" );

exit:

    if( ret != 0 && ret != 1)
    {
#ifdef MBEDTLS_ERROR_C
        mbedtls_strerror( ret, buf, sizeof( buf ) );
        mbedtls_printf( " - %s\n", buf );
#else
        mbedtls_printf("\n");
#endif
    }

    mbedtls_pk_free( &key );
    mbedtls_ctr_drbg_free( &ctr_drbg );
    mbedtls_entropy_free( &entropy );

#if defined(_WIN32)
    mbedtls_printf( "  + Press Enter to exit this program.\n" );
    fflush( stdout ); getchar();
#endif

    return( ret );
}
Example #18
0
/*
 * Parse an unencrypted PKCS#8 encoded private key
 */
static int pk_parse_key_pkcs8_unencrypted_der(
                                    mbedtls_pk_context *pk,
                                    const unsigned char* key,
                                    size_t keylen )
{
    int ret, version;
    size_t len;
    mbedtls_asn1_buf params;
    unsigned char *p = (unsigned char *) key;
    unsigned char *end = p + keylen;
    mbedtls_pk_type_t pk_alg = MBEDTLS_PK_NONE;
    const mbedtls_pk_info_t *pk_info;

    /*
     * This function parses the PrivatKeyInfo object (PKCS#8 v1.2 = RFC 5208)
     *
     *    PrivateKeyInfo ::= SEQUENCE {
     *      version                   Version,
     *      privateKeyAlgorithm       PrivateKeyAlgorithmIdentifier,
     *      privateKey                PrivateKey,
     *      attributes           [0]  IMPLICIT Attributes OPTIONAL }
     *
     *    Version ::= INTEGER
     *    PrivateKeyAlgorithmIdentifier ::= AlgorithmIdentifier
     *    PrivateKey ::= OCTET STRING
     *
     *  The PrivateKey OCTET STRING is a SEC1 ECPrivateKey
     */

    if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
            MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
    {
        return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT + ret );
    }

    end = p + len;

    if( ( ret = mbedtls_asn1_get_int( &p, end, &version ) ) != 0 )
        return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT + ret );

    if( version != 0 )
        return( MBEDTLS_ERR_PK_KEY_INVALID_VERSION + ret );

    if( ( ret = pk_get_pk_alg( &p, end, &pk_alg, &params ) ) != 0 )
        return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT + ret );

    if( ( ret = mbedtls_asn1_get_tag( &p, end, &len, MBEDTLS_ASN1_OCTET_STRING ) ) != 0 )
        return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT + ret );

    if( len < 1 )
        return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT +
                MBEDTLS_ERR_ASN1_OUT_OF_DATA );

    if( ( pk_info = mbedtls_pk_info_from_type( pk_alg ) ) == NULL )
        return( MBEDTLS_ERR_PK_UNKNOWN_PK_ALG );

    if( ( ret = mbedtls_pk_setup( pk, pk_info ) ) != 0 )
        return( ret );

#if defined(MBEDTLS_RSA_C)
    if( pk_alg == MBEDTLS_PK_RSA )
    {
        if( ( ret = pk_parse_key_pkcs1_der( mbedtls_pk_rsa( *pk ), p, len ) ) != 0 )
        {
            mbedtls_pk_free( pk );
            return( ret );
        }
    } else
#endif /* MBEDTLS_RSA_C */
#if defined(MBEDTLS_ECP_C)
    if( pk_alg == MBEDTLS_PK_ECKEY || pk_alg == MBEDTLS_PK_ECKEY_DH )
    {
        if( ( ret = pk_use_ecparams( &params, &mbedtls_pk_ec( *pk )->grp ) ) != 0 ||
            ( ret = pk_parse_key_sec1_der( mbedtls_pk_ec( *pk ), p, len )  ) != 0 )
        {
            mbedtls_pk_free( pk );
            return( ret );
        }
    } else
#endif /* MBEDTLS_ECP_C */
        return( MBEDTLS_ERR_PK_UNKNOWN_PK_ALG );

    return( 0 );
}
Example #19
0
/*
 * CSR is output formatted as b64url(DER)
 * Private key is output as a PEM in memory
 */
LWS_VISIBLE LWS_EXTERN int
lws_tls_acme_sni_csr_create(struct lws_context *context, const char *elements[],
			    uint8_t *dcsr, size_t csr_len, char **privkey_pem,
			    size_t *privkey_len)
{
	mbedtls_x509write_csr csr;
	char subject[200];
	mbedtls_pk_context mpk;
	int buf_size = 4096, n;
	uint8_t *buf = malloc(buf_size); /* malloc because given to user code */

	if (!buf)
		return -1;

	mbedtls_x509write_csr_init(&csr);

	mbedtls_pk_init(&mpk);
	if (mbedtls_pk_setup(&mpk, mbedtls_pk_info_from_type(MBEDTLS_PK_RSA))) {
		lwsl_notice("%s: pk_setup failed\n", __func__);
		goto fail;
	}

	n = mbedtls_rsa_gen_key(mbedtls_pk_rsa(mpk), _rngf, context,
				lws_plat_recommended_rsa_bits(), 65537);
	if (n) {
		lwsl_notice("%s: failed to generate keys\n", __func__);

		goto fail1;
	}

	/* subject must be formatted like "C=TW,O=warmcat,CN=myserver" */

	lws_snprintf(subject, sizeof(subject) - 1,
		     "C=%s,ST=%s,L=%s,O=%s,CN=%s",
		     elements[LWS_TLS_REQ_ELEMENT_COUNTRY],
		     elements[LWS_TLS_REQ_ELEMENT_STATE],
		     elements[LWS_TLS_REQ_ELEMENT_LOCALITY],
		     elements[LWS_TLS_REQ_ELEMENT_ORGANIZATION],
		     elements[LWS_TLS_REQ_ELEMENT_COMMON_NAME]);
	if (mbedtls_x509write_csr_set_subject_name(&csr, subject))
		goto fail1;

	mbedtls_x509write_csr_set_key(&csr, &mpk);
	mbedtls_x509write_csr_set_md_alg(&csr, MBEDTLS_MD_SHA256);

	/*
	 * data is written at the end of the buffer! Use the
	 * return value to determine where you should start
	 * using the buffer
	 */
	n = mbedtls_x509write_csr_der(&csr, buf, buf_size, _rngf, context);
	if (n < 0) {
		lwsl_notice("%s: write csr der failed\n", __func__);
		goto fail1;
	}

	/* we have it in DER, we need it in b64URL */

	n = lws_jws_base64_enc((char *)(buf + buf_size) - n, n,
			       (char *)dcsr, csr_len);
	if (n < 0)
		goto fail1;

	/*
	 * okay, the CSR is done, last we need the private key in PEM
	 * re-use the DER CSR buf as the result buffer since we cn do it in
	 * one step
	 */

	if (mbedtls_pk_write_key_pem(&mpk, buf, buf_size)) {
		lwsl_notice("write key pem failed\n");
		goto fail1;
	}

	*privkey_pem = (char *)buf;
	*privkey_len = strlen((const char *)buf);

	mbedtls_pk_free(&mpk);
	mbedtls_x509write_csr_free(&csr);

	return n;

fail1:
	mbedtls_pk_free(&mpk);
fail:
	mbedtls_x509write_csr_free(&csr);
	free(buf);

	return -1;
}