/src/bind9/lib/isc/ossl_wrap/ossl3.c

Source
/*
 * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
 *
 * SPDX-License-Identifier: MPL-2.0
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, you can obtain one at https://mozilla.org/MPL/2.0/.
 *
 * See the COPYRIGHT file distributed with this work for additional
 * information regarding copyright ownership.
 */

#include <stdbool.h>
#include <string.h>

#include <openssl/bn.h>
#include <openssl/core_names.h>
#include <openssl/ec.h>
#include <openssl/err.h>
#include <openssl/evp.h>
#include <openssl/param_build.h>
#include <openssl/rsa.h>

#include <isc/crypto.h>
#include <isc/ossl_wrap.h>
#include <isc/region.h>
#include <isc/util.h>

#define MAX_PUBLIC_KEY_SIZE 96
#define MAX_SECRET_KEY_SIZE 48

#define OSSL_WRAP_ERROR(fn)                                        \
  isc__ossl_wrap_logged_toresult(                            \
    ISC_LOGCATEGORY_GENERAL, ISC_LOGMODULE_CRYPTO, fn, \
    ISC_R_CRYPTOFAILURE, __FILE__, __LINE__)

#define P_CURVE_IMPL(curve, nid)                                               \
  isc_result_t isc_ossl_wrap_generate_##curve##_key(EVP_PKEY **pkeyp) {  \
    REQUIRE(pkeyp != NULL && *pkeyp == NULL);                      \
    return generate_ec_key(pkeyp, curve##_params);                 \
  }                                                                      \
  isc_result_t isc_ossl_wrap_generate_pkcs11_##curve##_key(              \
    char *uri, EVP_PKEY **pkeyp) {                                 \
    REQUIRE(pkeyp != NULL && *pkeyp == NULL);                      \
    REQUIRE(uri != NULL);                                          \
    return generate_pkcs11_ec_key(uri, pkeyp, nid);                \
  }                                                                      \
  isc_result_t isc_ossl_wrap_validate_##curve##_pkey(EVP_PKEY *pkey) {   \
    REQUIRE(pkey != NULL);                                         \
    return validate_ec_pkey(pkey, curve##_params);                 \
  }                                                                      \
  isc_result_t isc_ossl_wrap_load_##curve##_public_from_region(          \
    isc_region_t region, EVP_PKEY **pkeyp) {                       \
    REQUIRE(region.base != NULL &&                                 \
      region.length <= MAX_PUBLIC_KEY_SIZE);                 \
    REQUIRE(pkeyp != NULL && *pkeyp == NULL);                      \
    region.length = curve##_public_key_size;                       \
    return load_ec_public_from_region(region, pkeyp,               \
              curve##_params);             \
  }                                                                      \
  isc_result_t isc_ossl_wrap_load_##curve##_secret_from_region(          \
    isc_region_t region, EVP_PKEY **pkeyp) {                       \
    REQUIRE(pkeyp != NULL && *pkeyp == NULL);                      \
    REQUIRE(region.base != NULL &&                                 \
      region.length >= curve##_secret_key_size);             \
    region.length = curve##_secret_key_size;                       \
    return load_ec_secret_from_region(region, pkeyp,               \
              curve##_params);             \
  }                                                                      \
  isc_result_t isc_ossl_wrap_##curve##_public_region(EVP_PKEY *pkey,     \
                 isc_region_t pub) { \
    REQUIRE(pkey != NULL);                                         \
    REQUIRE(pub.base != NULL &&                                    \
      pub.length >= curve##_public_key_size);                \
    pub.length = curve##_public_key_size;                          \
    return ec_public_region(pkey, pub);                            \
  }                                                                      \
  isc_result_t isc_ossl_wrap_##curve##_secret_region(EVP_PKEY *pkey,     \
                 isc_region_t sec) { \
    REQUIRE(pkey != NULL);                                         \
    REQUIRE(sec.base != NULL &&                                    \
      sec.length >= curve##_secret_key_size);                \
    sec.length = curve##_secret_key_size;                          \
    return ec_secret_region(pkey, sec);                            \
  }

static char pkcs11_key_usage[] = "digitalSignature";

constexpr size_t p256_public_key_size = 64;
constexpr size_t p384_public_key_size = 96;

constexpr size_t p256_secret_key_size = 32;
constexpr size_t p384_secret_key_size = 48;

/*
 * "group" MUST be the first parameter, we rely on it to get the group name.
 */

/* clang-format off */
static const OSSL_PARAM p256_params[] = {
  OSSL_PARAM_utf8_string(OSSL_PKEY_PARAM_GROUP_NAME,
             UNCONST("prime256v1"), sizeof("prime256v1") - 1),
  OSSL_PARAM_utf8_string(OSSL_PKEY_PARAM_EC_ENCODING,
             UNCONST("named_curve"), sizeof("named_curve") - 1),
  OSSL_PARAM_utf8_string(OSSL_PKEY_PARAM_EC_POINT_CONVERSION_FORMAT,
             UNCONST("uncompressed"), sizeof("uncompressed") - 1),
  OSSL_PARAM_END,
};

static const OSSL_PARAM p384_params[] = {
  OSSL_PARAM_utf8_string(OSSL_PKEY_PARAM_GROUP_NAME,
             UNCONST("secp384r1"), sizeof("secp384r1") - 1),
  OSSL_PARAM_utf8_string(OSSL_PKEY_PARAM_EC_ENCODING,
             UNCONST("named_curve"), sizeof("named_curve") - 1),
  OSSL_PARAM_utf8_string(OSSL_PKEY_PARAM_EC_POINT_CONVERSION_FORMAT,
             UNCONST("uncompressed"), sizeof("uncompressed") - 1),
  OSSL_PARAM_END,
};
/* clang-format on */

static void
BN_bn2bin_fixed(const BIGNUM *bn, unsigned char *buf, int size) {
  int bytes = size - BN_num_bytes(bn);

  INSIST(bytes >= 0);

  while (bytes-- > 0) {
    *buf++ = 0;
  }
  BN_bn2bin(bn, buf);
}

static int
rsa_keygen_progress_cb(EVP_PKEY_CTX *ctx) {
  void (*fptr)(int);

  fptr = EVP_PKEY_CTX_get_app_data(ctx);
  if (fptr != NULL) {
    int p = EVP_PKEY_CTX_get_keygen_info(ctx, 0);
    fptr(p);
  }
  return 1;
}

static isc_result_t
generate_ec_key(EVP_PKEY **pkeyp, const OSSL_PARAM *const params) {
  isc_result_t result;
  EVP_PKEY_CTX *pctx = NULL;

  pctx = EVP_PKEY_CTX_new_from_name(NULL, "EC", NULL);
  if (pctx == NULL) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_CTX_new_from_name"));
  }

  if (EVP_PKEY_keygen_init(pctx) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_keygen_init"));
  }

  if (EVP_PKEY_CTX_set_params(pctx, params) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_CTX_set_params"));
  }

  /*
   * EVP_PKEY_keygen is an older function now equivalent to
   * EVP_PKEY_generate with an additional check that EVP_PKEY_CTX has been
   * initialized with EVP_PKEY_keygen_init.
   *
   * Since we can guarantee such condition we use EVP_PKEY_generate
   * directly.
   */
  if (EVP_PKEY_generate(pctx, pkeyp) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_generate"));
  }

  result = ISC_R_SUCCESS;

cleanup:
  EVP_PKEY_CTX_free(pctx);
  return result;
}

static isc_result_t
generate_pkcs11_ec_key(char *uri, EVP_PKEY **pkeyp, int nid) {
  isc_result_t result;
  EVP_PKEY_CTX *pctx;
  size_t len;

  INSIST(uri != NULL);
  len = strlen(uri);

  const OSSL_PARAM params[] = {
    OSSL_PARAM_utf8_string("pkcs11_uri", uri, len),
    OSSL_PARAM_utf8_string("pkcs11_key_usage", pkcs11_key_usage,
               sizeof(pkcs11_key_usage) - 1),
    OSSL_PARAM_END,
  };

  pctx = EVP_PKEY_CTX_new_from_name(NULL, "EC", "provider=pkcs11");
  if (pctx == NULL) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_CTX_new_from_name"));
  }

  if (EVP_PKEY_keygen_init(pctx) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_keygen_init"));
  }

  if (EVP_PKEY_CTX_set_params(pctx, params) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_CTX_set_params"));
  }

  /*
   * Setting the P-384 curve doesn't work correctly when using:
   * OSSL_PARAM_construct_utf8_string("ec_paramgen_curve", "P-384", 0);
   *
   * Instead use the OpenSSL function to set the curve nid param.
   */
  if (EVP_PKEY_CTX_set_ec_paramgen_curve_nid(pctx, nid) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_CTX_set_ec_paramgen_curve_"
          "nid"));
  }

  /*
   * EVP_PKEY_keygen is an older function now equivalent to
   * EVP_PKEY_generate with an additional check that EVP_PKEY_CTX has been
   * initialized with EVP_PKEY_keygen_init.
   *
   * Since we can guarantee such condition we use EVP_PKEY_generate
   * directly.
   */
  if (EVP_PKEY_generate(pctx, pkeyp) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_generate"));
  }

  result = ISC_R_SUCCESS;

cleanup:
  EVP_PKEY_CTX_free(pctx);
  return result;
}

static isc_result_t
generate_pkcs11_eddsa_key(char *uri, EVP_PKEY **pkeyp, const char *keytype) {
  isc_result_t result;
  EVP_PKEY_CTX *pctx = NULL;
  size_t len;

  INSIST(uri != NULL);
  len = strlen(uri);

  const OSSL_PARAM params[] = {
    OSSL_PARAM_utf8_string("pkcs11_uri", uri, len),
    OSSL_PARAM_utf8_string("pkcs11_key_usage", pkcs11_key_usage,
               sizeof(pkcs11_key_usage) - 1),
    OSSL_PARAM_END,
  };

  pctx = EVP_PKEY_CTX_new_from_name(NULL, keytype, "provider=pkcs11");
  if (pctx == NULL) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_CTX_new_from_name"));
  }

  if (EVP_PKEY_keygen_init(pctx) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_keygen_init"));
  }

  if (EVP_PKEY_CTX_set_params(pctx, params) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_CTX_set_params"));
  }

  if (EVP_PKEY_generate(pctx, pkeyp) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_generate"));
  }

  result = ISC_R_SUCCESS;

cleanup:
  EVP_PKEY_CTX_free(pctx);
  return result;
}

isc_result_t
isc_ossl_wrap_generate_pkcs11_ed25519_key(char *uri, EVP_PKEY **pkeyp) {
  REQUIRE(pkeyp != NULL && *pkeyp == NULL);
  REQUIRE(uri != NULL);
  return generate_pkcs11_eddsa_key(uri, pkeyp, "ED25519");
}

isc_result_t
isc_ossl_wrap_generate_pkcs11_ed448_key(char *uri, EVP_PKEY **pkeyp) {
  REQUIRE(pkeyp != NULL && *pkeyp == NULL);
  REQUIRE(uri != NULL);
  return generate_pkcs11_eddsa_key(uri, pkeyp, "ED448");
}

static isc_result_t
validate_ec_pkey(EVP_PKEY *pkey, const OSSL_PARAM *const curve_params) {
  isc_result_t result;
  const char *expected = curve_params[0].data;
  char actual[64];

  if (EVP_PKEY_get_group_name(pkey, actual, sizeof(actual), NULL) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_get_group_name"));
  }

  if (strncmp(expected, actual, curve_params[0].data_size) != 0) {
    return ISC_R_FAILURE;
  }

  result = ISC_R_SUCCESS;

cleanup:
  return result;
}

static isc_result_t
load_ec_public_from_region(isc_region_t region, EVP_PKEY **pkeyp,
         const OSSL_PARAM *const curve_params) {
  isc_result_t result;
  EVP_PKEY_CTX *pctx = NULL;
  uint8_t buffer[MAX_PUBLIC_KEY_SIZE + 1];
  OSSL_PARAM params[] = {
    curve_params[0], /* group */
    OSSL_PARAM_octet_string(OSSL_PKEY_PARAM_PUB_KEY, buffer,
          region.length + 1),
    OSSL_PARAM_END,
  };

  buffer[0] = POINT_CONVERSION_UNCOMPRESSED;
  memmove(buffer + 1, region.base, region.length);

  pctx = EVP_PKEY_CTX_new_from_name(NULL, "EC", NULL);
  if (pctx == NULL) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_CTX_new_from_name"));
  }

  if (EVP_PKEY_fromdata_init(pctx) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_fromdata_init"));
  }

  if (EVP_PKEY_fromdata(pctx, pkeyp, EVP_PKEY_PUBLIC_KEY, params) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_fromdata"));
  }

  result = ISC_R_SUCCESS;

cleanup:
  EVP_PKEY_CTX_free(pctx);
  return result;
}

static isc_result_t
load_ec_secret_from_region(isc_region_t region, EVP_PKEY **pkeyp,
         const OSSL_PARAM *const curve_params) {
  uint8_t public[MAX_PUBLIC_KEY_SIZE + 1];
  OSSL_PARAM_BLD *bld = NULL;
  OSSL_PARAM *params = NULL;
  EVP_PKEY_CTX *pctx = NULL;
  EC_POINT *pub_point = NULL;
  EC_GROUP *group = NULL;
  BIGNUM *private = NULL;
  isc_result_t result;
  size_t public_len;

  /*
   * OpenSSL requires us to set the public key portion, but since our
   * private key file format does not contain it directly, we generate it
   * as needed.
   */
  group = EC_GROUP_new_from_params(curve_params, NULL, NULL);
  if (group == NULL) {
    CLEANUP(OSSL_WRAP_ERROR("EC_GROUP_new_by_curve_name"));
  }

  private = BN_bin2bn(region.base, region.length, NULL);
  if (private == NULL) {
    CLEANUP(OSSL_WRAP_ERROR("BN_bin2bn"));
  }

  pub_point = EC_POINT_new(group);
  if (pub_point == NULL) {
    CLEANUP(OSSL_WRAP_ERROR("EC_POINT_new"));
  }

  if (EC_POINT_mul(group, pub_point, private, NULL, NULL, NULL) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("EC_POINT_mul"));
  }

  public_len = EC_POINT_point2oct(group, pub_point,
          POINT_CONVERSION_UNCOMPRESSED, public,
          sizeof(public), NULL);
  if (public_len == 0) {
    CLEANUP(OSSL_WRAP_ERROR("EC_POINT_point2oct"));
  }

  bld = OSSL_PARAM_BLD_new();
  if (bld == NULL) {
    CLEANUP(OSSL_WRAP_ERROR("OSSL_PARAM_BLD_new"));
  }

  if (OSSL_PARAM_BLD_push_utf8_string(bld, curve_params[0].key,
              curve_params[0].data,
              curve_params[0].data_size) != 1)
  {
    CLEANUP(OSSL_WRAP_ERROR("OSSL_PARAM_BLD_push_utf8_string"));
  }

  if (OSSL_PARAM_BLD_push_BN(bld, OSSL_PKEY_PARAM_PRIV_KEY, private) != 1)
  {
    CLEANUP(OSSL_WRAP_ERROR("OSSL_PARAM_BLD_push_BN"));
  }

  if (OSSL_PARAM_BLD_push_octet_string(bld, OSSL_PKEY_PARAM_PUB_KEY,
               public, public_len) != 1)
  {
    CLEANUP(OSSL_WRAP_ERROR("OSSL_PARAM_BLD_push_octet_string"));
  }

  params = OSSL_PARAM_BLD_to_param(bld);
  if (params == NULL) {
    CLEANUP(OSSL_WRAP_ERROR("OSSL_PARAM_BLD_to_param"));
  }

  pctx = EVP_PKEY_CTX_new_from_name(NULL, "EC", NULL);
  if (pctx == NULL) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_CTX_new_from_name"));
  }

  if (EVP_PKEY_fromdata_init(pctx) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_fromdata_init"));
  }

  if (EVP_PKEY_fromdata(pctx, pkeyp, EVP_PKEY_KEYPAIR, params) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_fromdata"));
  }

  result = ISC_R_SUCCESS;

cleanup:
  OSSL_PARAM_free(params);
  OSSL_PARAM_BLD_free(bld);
  EC_POINT_free(pub_point);
  BN_clear_free(private);
  EC_GROUP_free(group);
  EVP_PKEY_CTX_free(pctx);
  return result;
}

static isc_result_t
ec_public_region(EVP_PKEY *pkey, isc_region_t pub) {
  isc_result_t result;
  BIGNUM *x = NULL;
  BIGNUM *y = NULL;

  if (EVP_PKEY_get_bn_param(pkey, OSSL_PKEY_PARAM_EC_PUB_X, &x) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_get_bn_param"));
  }

  if (EVP_PKEY_get_bn_param(pkey, OSSL_PKEY_PARAM_EC_PUB_Y, &y) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_get_bn_param"));
  }

  BN_bn2bin_fixed(x, &pub.base[0], pub.length / 2);
  BN_bn2bin_fixed(y, &pub.base[pub.length / 2], pub.length / 2);

  result = ISC_R_SUCCESS;

cleanup:
  BN_clear_free(x);
  BN_clear_free(y);
  return result;
}

static isc_result_t
ec_secret_region(EVP_PKEY *pkey, isc_region_t sec) {
  isc_result_t result;
  BIGNUM *priv = NULL;

  if (EVP_PKEY_get_bn_param(pkey, OSSL_PKEY_PARAM_PRIV_KEY, &priv) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_get_bn_param"));
  }

  BN_bn2bin_fixed(priv, sec.base, sec.length);

  result = ISC_R_SUCCESS;

cleanup:
  BN_clear_free(priv);
  return result;
}

P_CURVE_IMPL(p256, NID_X9_62_prime256v1);
P_CURVE_IMPL(p384, NID_secp384r1);

isc_result_t
isc_ossl_wrap_ecdsa_set_deterministic(EVP_PKEY_CTX *pctx, const char *hash) {
  unsigned int rfc6979 = 1;
  isc_result_t result;
  OSSL_PARAM params[3] = {
    OSSL_PARAM_construct_utf8_string("digest", UNCONST(hash), 0),
    OSSL_PARAM_construct_uint("nonce-type", &rfc6979),
    OSSL_PARAM_END,
  };

  REQUIRE(pctx != NULL && hash != NULL);

  if (EVP_PKEY_CTX_set_params(pctx, params) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_CTX_set_params"));
  }

  result = ISC_R_SUCCESS;

cleanup:
  return result;
}

isc_result_t
isc_ossl_wrap_generate_rsa_key(void (*callback)(int), size_t bit_size,
             EVP_PKEY **pkeyp) {
  isc_result_t result;
  EVP_PKEY_CTX *ctx;
  uint32_t e = 65537;

  REQUIRE(pkeyp != NULL && *pkeyp == NULL);

  /*
   * https://docs.openssl.org/master/man7/EVP_PKEY-RSA/#rsa-key-generation-parameters
   */
  const OSSL_PARAM params[3] = {
    OSSL_PARAM_uint(OSSL_PKEY_PARAM_RSA_E, &e),
    OSSL_PARAM_size_t(OSSL_PKEY_PARAM_RSA_BITS, &bit_size),
    OSSL_PARAM_END,
  };

  ctx = EVP_PKEY_CTX_new_from_name(NULL, "RSA", NULL);
  if (ctx == NULL) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_CTX_new_from_name"));
  }

  if (EVP_PKEY_keygen_init(ctx) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_keygen_init"));
  }

  if (EVP_PKEY_CTX_set_params(ctx, params) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_CTX_set_params"));
  }

  if (callback != NULL) {
    EVP_PKEY_CTX_set_app_data(ctx, (void *)callback);
    EVP_PKEY_CTX_set_cb(ctx, rsa_keygen_progress_cb);
  }

  /*
   * EVP_PKEY_keygen is an older function now equivalent to
   * EVP_PKEY_generate with an additional check that EVP_PKEY_CTX has been
   * initialized with EVP_PKEY_keygen_init.
   *
   * Since we can guarantee such condition we use EVP_PKEY_generate
   * directly.
   */
  if (EVP_PKEY_generate(ctx, pkeyp) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_keygen"));
  }

  result = ISC_R_SUCCESS;

cleanup:
  EVP_PKEY_CTX_free(ctx);
  return result;
}

isc_result_t
isc_ossl_wrap_generate_pkcs11_rsa_key(char *uri, size_t bit_size,
              EVP_PKEY **pkeyp) {
  EVP_PKEY_CTX *ctx = NULL;
  isc_result_t result;
  int status;
  size_t len;

  REQUIRE(uri != NULL);
  REQUIRE(pkeyp != NULL && *pkeyp == NULL);

  len = strlen(uri);
  INSIST(len != 0);

  /* NUL-terminator should be left out */
  const OSSL_PARAM params[] = {
    OSSL_PARAM_utf8_string("pkcs11_uri", uri, len),
    OSSL_PARAM_utf8_string("pkcs11_key_usage", pkcs11_key_usage,
               sizeof(pkcs11_key_usage) - 1),
    OSSL_PARAM_size_t(OSSL_PKEY_PARAM_RSA_BITS, &bit_size),
    OSSL_PARAM_END,
  };

  ctx = EVP_PKEY_CTX_new_from_name(NULL, "RSA", "provider=pkcs11");
  if (ctx == NULL) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_CTX_new_from_name"));
  }

  status = EVP_PKEY_keygen_init(ctx);
  if (status != 1) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_keygen_init"));
  }

  status = EVP_PKEY_CTX_set_params(ctx, params);
  if (status != 1) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_CTX_set_params"));
  }

  /*
   * EVP_PKEY_keygen is an older function now equivalent to
   * EVP_PKEY_generate with an additional check that EVP_PKEY_CTX has been
   * initialized with EVP_PKEY_keygen_init.
   *
   * Since we can guarantee such condition we use EVP_PKEY_generate
   * directly.
   */
  status = EVP_PKEY_generate(ctx, pkeyp);
  if (status != 1) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_generate"));
  }

  result = ISC_R_SUCCESS;

cleanup:
  EVP_PKEY_CTX_free(ctx);
  return result;
}

bool
isc_ossl_wrap_rsa_exponent_is_allowed(EVP_PKEY *pkey) {
  BIGNUM *e = NULL;
  BIGNUM *emin = NULL;
  BIGNUM *emax = NULL;
  bool ok = false;

  if (EVP_PKEY_get_bn_param(pkey, OSSL_PKEY_PARAM_RSA_E, &e) != 1) {
    goto cleanup;
  }

  emin = BN_new();
  if (emin == NULL || !BN_set_word(emin, 3)) {
    goto cleanup;
  }
  if (BN_hex2bn(&emax, "100000001") == 0) {
    goto cleanup;
  }

  ok = BN_is_odd(e) && BN_cmp(e, emin) >= 0 && BN_cmp(e, emax) <= 0;

cleanup:
  BN_free(e);
  BN_free(emin);
  BN_free(emax);
  return ok;
}

bool
isc_ossl_wrap_rsa_modulus_bits_in_range(EVP_PKEY *pkey, size_t min,
          size_t max) {
  REQUIRE(pkey != NULL);

  int bits = EVP_PKEY_bits(pkey);
  return bits > 0 && (size_t)bits >= min && (size_t)bits <= max;
}

isc_result_t
isc_ossl_wrap_rsa_public_components(EVP_PKEY *pkey,
            isc_ossl_wrap_rsa_components_t *c) {
  isc_result_t result;

  REQUIRE(pkey != NULL);
  REQUIRE(c != NULL && c->e == NULL && c->n == NULL);

  c->needs_cleanup = true;

  if (EVP_PKEY_get_bn_param(pkey, OSSL_PKEY_PARAM_RSA_E, &c->e) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_get_bn_param"));
  }

  if (EVP_PKEY_get_bn_param(pkey, OSSL_PKEY_PARAM_RSA_N, &c->n) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_get_bn_param"));
  }

  result = ISC_R_SUCCESS;

cleanup:
  return result;
}

isc_result_t
isc_ossl_wrap_rsa_secret_components(EVP_PKEY *pkey,
            isc_ossl_wrap_rsa_components_t *c) {
  REQUIRE(pkey != NULL);
  REQUIRE(c != NULL && c->d == NULL && c->p == NULL && c->q == NULL &&
    c->dmp1 == NULL && c->dmq1 == NULL && c->iqmp == NULL);

  c->needs_cleanup = true;

  /*
   * NOTE: Errors regarding private compoments are ignored.
   *
   * OpenSSL allows omitting the parameters for CRT based calculations
   * (factors, exponents, coefficients). Only the 'd'  parameter is
   * mandatory for software keys.
   *
   * However, for a label based keys, all private key component queries
   * can fail if they key is e.g. on a hardware device.
   */
  (void)EVP_PKEY_get_bn_param(pkey, OSSL_PKEY_PARAM_RSA_D, &c->d);
  (void)EVP_PKEY_get_bn_param(pkey, OSSL_PKEY_PARAM_RSA_FACTOR1, &c->p);
  (void)EVP_PKEY_get_bn_param(pkey, OSSL_PKEY_PARAM_RSA_FACTOR2, &c->q);
  (void)EVP_PKEY_get_bn_param(pkey, OSSL_PKEY_PARAM_RSA_EXPONENT1,
            &c->dmp1);
  (void)EVP_PKEY_get_bn_param(pkey, OSSL_PKEY_PARAM_RSA_EXPONENT2,
            &c->dmq1);
  (void)EVP_PKEY_get_bn_param(pkey, OSSL_PKEY_PARAM_RSA_COEFFICIENT1,
            &c->iqmp);

  ERR_clear_error();

  return ISC_R_SUCCESS;
}

isc_result_t
isc_ossl_wrap_load_rsa_public_from_components(isc_ossl_wrap_rsa_components_t *c,
                EVP_PKEY **pkeyp) {
  OSSL_PARAM_BLD *bld = NULL;
  EVP_PKEY_CTX *pctx = NULL;
  OSSL_PARAM *params = NULL;
  isc_result_t result;

  REQUIRE(pkeyp != NULL && *pkeyp == NULL);
  REQUIRE(c != NULL && c->n != NULL && c->e != NULL);

  bld = OSSL_PARAM_BLD_new();
  if (bld == NULL) {
    CLEANUP(OSSL_WRAP_ERROR("OSSL_PARAM_BLD_new"));
  }

  if (OSSL_PARAM_BLD_push_BN(bld, OSSL_PKEY_PARAM_RSA_N, c->n) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("OSSL_PARAM_BLD_push_BN"));
  }

  if (OSSL_PARAM_BLD_push_BN(bld, OSSL_PKEY_PARAM_RSA_E, c->e) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("OSSL_PARAM_BLD_push_BN"));
  }

  params = OSSL_PARAM_BLD_to_param(bld);
  if (params == NULL) {
    CLEANUP(OSSL_WRAP_ERROR("OSSL_PARAM_BLD_to_param"));
  }

  pctx = EVP_PKEY_CTX_new_from_name(NULL, "RSA", NULL);
  if (pctx == NULL) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_CTX_new_from_name"));
  }

  if (EVP_PKEY_fromdata_init(pctx) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_fromdata_init"));
  }

  if (EVP_PKEY_fromdata(pctx, pkeyp, EVP_PKEY_PUBLIC_KEY, params) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_fromdata"));
  }

  result = ISC_R_SUCCESS;

cleanup:
  EVP_PKEY_CTX_free(pctx);
  OSSL_PARAM_free(params);
  OSSL_PARAM_BLD_free(bld);
  return result;
}

isc_result_t
isc_ossl_wrap_load_rsa_secret_from_components(isc_ossl_wrap_rsa_components_t *c,
                EVP_PKEY **pkeyp) {
  isc_result_t result;
  OSSL_PARAM_BLD *bld = NULL;
  EVP_PKEY_CTX *pctx = NULL;
  OSSL_PARAM *params = NULL;

  REQUIRE(pkeyp != NULL && *pkeyp == NULL);

  bld = OSSL_PARAM_BLD_new();
  if (bld == NULL) {
    CLEANUP(OSSL_WRAP_ERROR("OSSL_PARAM_BLD_new"));
  }

  if (OSSL_PARAM_BLD_push_BN(bld, OSSL_PKEY_PARAM_RSA_N, c->n) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("OSSL_PARAM_BLD_push_BN"));
  }

  if (OSSL_PARAM_BLD_push_BN(bld, OSSL_PKEY_PARAM_RSA_E, c->e) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("OSSL_PARAM_BLD_push_BN"));
  }

  if (c->d != NULL &&
      OSSL_PARAM_BLD_push_BN(bld, OSSL_PKEY_PARAM_RSA_D, c->d) != 1)
  {
    CLEANUP(OSSL_WRAP_ERROR("OSSL_PARAM_BLD_push_BN"));
  }

  if (c->p != NULL &&
      OSSL_PARAM_BLD_push_BN(bld, OSSL_PKEY_PARAM_RSA_FACTOR1, c->p) != 1)
  {
    CLEANUP(OSSL_WRAP_ERROR("OSSL_PARAM_BLD_push_BN"));
  }

  if (c->q != NULL &&
      OSSL_PARAM_BLD_push_BN(bld, OSSL_PKEY_PARAM_RSA_FACTOR2, c->q) != 1)
  {
    CLEANUP(OSSL_WRAP_ERROR("OSSL_PARAM_BLD_push_BN"));
  }

  if (c->dmp1 != NULL &&
      OSSL_PARAM_BLD_push_BN(bld, OSSL_PKEY_PARAM_RSA_EXPONENT1,
           c->dmp1) != 1)
  {
    CLEANUP(OSSL_WRAP_ERROR("OSSL_PARAM_BLD_push_BN"));
  }

  if (c->dmq1 != NULL &&
      OSSL_PARAM_BLD_push_BN(bld, OSSL_PKEY_PARAM_RSA_EXPONENT2,
           c->dmq1) != 1)
  {
    CLEANUP(OSSL_WRAP_ERROR("OSSL_PARAM_BLD_push_BN"));
  }

  if (c->iqmp != NULL &&
      OSSL_PARAM_BLD_push_BN(bld, OSSL_PKEY_PARAM_RSA_COEFFICIENT1,
           c->iqmp) != 1)
  {
    CLEANUP(OSSL_WRAP_ERROR("OSSL_PARAM_BLD_push_BN"));
  }

  params = OSSL_PARAM_BLD_to_param(bld);
  if (params == NULL) {
    CLEANUP(OSSL_WRAP_ERROR("OSSL_PARAM_BLD_to_param"));
  }

  pctx = EVP_PKEY_CTX_new_from_name(NULL, "RSA", NULL);
  if (pctx == NULL) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_CTX_new_from_name"));
  }

  if (EVP_PKEY_fromdata_init(pctx) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_fromdata_init"));
  }

  if (EVP_PKEY_fromdata(pctx, pkeyp, EVP_PKEY_KEYPAIR, params) != 1) {
    CLEANUP(OSSL_WRAP_ERROR("EVP_PKEY_fromdata"));
  }

  result = ISC_R_SUCCESS;

cleanup:
  EVP_PKEY_CTX_free(pctx);
  OSSL_PARAM_free(params);
  OSSL_PARAM_BLD_free(bld);
  return result;
}

Coverage Report

Created: 2026-07-16 07:05