static int
_wrap_nettle_pk_encrypt(gnutls_pk_algorithm_t algo,
gnutls_datum_t * ciphertext,
const gnutls_datum_t * plaintext,
const gnutls_pk_params_st * pk_params)
{
int ret;
mpz_t p;
mpz_init(p);
switch (algo) {
case GNUTLS_PK_RSA:
{
struct rsa_public_key pub;
_rsa_params_to_pubkey(pk_params, &pub);
ret =
rsa_encrypt(&pub, NULL, rnd_func,
plaintext->size, plaintext->data,
p);
if (ret == 0) {
ret =
gnutls_assert_val
(GNUTLS_E_ENCRYPTION_FAILED);
goto cleanup;
}
ret =
_gnutls_mpi_dprint_size(p, ciphertext,
pub.size);
if (ret < 0) {
gnutls_assert();
goto cleanup;
}
break;
}
default:
gnutls_assert();
ret = GNUTLS_E_INTERNAL_ERROR;
goto cleanup;
}
ret = 0;
cleanup:
mpz_clear(p);
FAIL_IF_LIB_ERROR;
return ret;
}
static int
_wrap_nettle_pk_verify (gnutls_pk_algorithm_t algo,
const gnutls_datum_t * vdata,
const gnutls_datum_t * signature,
const gnutls_pk_params_st * pk_params)
{
int ret;
unsigned int hash_len;
bigint_t tmp[2] = { NULL, NULL };
switch (algo)
{
case GNUTLS_PK_EC: /* ECDSA */
{
ecc_key pub;
struct dsa_signature sig;
int stat;
int curve_id = pk_params->flags;
if (is_supported_curve(curve_id) == 0)
return gnutls_assert_val(GNUTLS_E_ECC_UNSUPPORTED_CURVE);
ret = _gnutls_decode_ber_rs (signature, &tmp[0], &tmp[1]);
if (ret < 0)
{
gnutls_assert ();
goto cleanup;
}
_ecc_params_to_pubkey(pk_params, &pub);
memcpy (&sig.r, tmp[0], sizeof (sig.r));
memcpy (&sig.s, tmp[1], sizeof (sig.s));
_gnutls_dsa_q_to_hash (algo, pk_params, &hash_len);
if (hash_len > vdata->size)
hash_len = vdata->size;
ret = ecc_verify_hash(&sig, vdata->data, hash_len, &stat, &pub, curve_id);
if (ret != 0 || stat != 1)
{
gnutls_assert();
ret = GNUTLS_E_PK_SIG_VERIFY_FAILED;
}
else
ret = 0;
_gnutls_mpi_release (&tmp[0]);
_gnutls_mpi_release (&tmp[1]);
_ecc_params_clear( &pub);
break;
}
case GNUTLS_PK_DSA:
{
struct dsa_public_key pub;
struct dsa_signature sig;
ret = _gnutls_decode_ber_rs (signature, &tmp[0], &tmp[1]);
if (ret < 0)
{
gnutls_assert ();
goto cleanup;
}
memset(&pub, 0, sizeof(pub));
_dsa_params_to_pubkey (pk_params, &pub);
memcpy (&sig.r, tmp[0], sizeof (sig.r));
memcpy (&sig.s, tmp[1], sizeof (sig.s));
_gnutls_dsa_q_to_hash (algo, pk_params, &hash_len);
if (hash_len > vdata->size)
hash_len = vdata->size;
ret = _dsa_verify (&pub, hash_len, vdata->data, &sig);
if (ret == 0)
{
gnutls_assert();
ret = GNUTLS_E_PK_SIG_VERIFY_FAILED;
}
else
ret = 0;
_gnutls_mpi_release (&tmp[0]);
_gnutls_mpi_release (&tmp[1]);
break;
}
case GNUTLS_PK_RSA:
{
struct rsa_public_key pub;
_rsa_params_to_pubkey (pk_params, &pub);
ret = _gnutls_mpi_scan_nz (&tmp[0], signature->data, signature->size);
if (ret < 0)
{
gnutls_assert ();
goto cleanup;
}
ret = rsa_pkcs1_verify (&pub, vdata->size, vdata->data, TOMPZ(tmp[0]));
if (ret == 0)
ret = gnutls_assert_val(GNUTLS_E_PK_SIG_VERIFY_FAILED);
else ret = 0;
_gnutls_mpi_release (&tmp[0]);
break;
}
default:
gnutls_assert ();
ret = GNUTLS_E_INTERNAL_ERROR;
goto cleanup;
}
cleanup:
return ret;
}
/* in case of DSA puts into data, r,s
*/
static int
_wrap_nettle_pk_sign (gnutls_pk_algorithm_t algo,
gnutls_datum_t * signature,
const gnutls_datum_t * vdata,
const gnutls_pk_params_st * pk_params)
{
int ret;
unsigned int hash;
unsigned int hash_len;
switch (algo)
{
case GNUTLS_PK_EC: /* we do ECDSA */
{
ecc_key priv;
struct dsa_signature sig;
int curve_id = pk_params->flags;
if (is_supported_curve(curve_id) == 0)
return gnutls_assert_val(GNUTLS_E_ECC_UNSUPPORTED_CURVE);
_ecc_params_to_privkey(pk_params, &priv);
dsa_signature_init (&sig);
hash = _gnutls_dsa_q_to_hash (algo, pk_params, &hash_len);
if (hash_len > vdata->size)
{
gnutls_assert ();
_gnutls_debug_log("Security level of algorithm requires hash %s(%d) or better\n", gnutls_mac_get_name(hash), hash_len);
hash_len = vdata->size;
}
ret = ecc_sign_hash(vdata->data, hash_len,
&sig, NULL, rnd_func, &priv, curve_id);
if (ret != 0)
{
gnutls_assert ();
ret = GNUTLS_E_PK_SIGN_FAILED;
goto ecdsa_fail;
}
ret = _gnutls_encode_ber_rs (signature, &sig.r, &sig.s);
ecdsa_fail:
dsa_signature_clear (&sig);
_ecc_params_clear( &priv);
if (ret < 0)
{
gnutls_assert ();
goto cleanup;
}
break;
}
case GNUTLS_PK_DSA:
{
struct dsa_public_key pub;
struct dsa_private_key priv;
struct dsa_signature sig;
memset(&priv, 0, sizeof(priv));
memset(&pub, 0, sizeof(pub));
_dsa_params_to_pubkey (pk_params, &pub);
_dsa_params_to_privkey (pk_params, &priv);
dsa_signature_init (&sig);
hash = _gnutls_dsa_q_to_hash (algo, pk_params, &hash_len);
if (hash_len > vdata->size)
{
gnutls_assert ();
_gnutls_debug_log("Security level of algorithm requires hash %s(%d) or better\n", gnutls_mac_get_name(hash), hash_len);
hash_len = vdata->size;
}
ret =
_dsa_sign (&pub, &priv, NULL, rnd_func,
hash_len, vdata->data, &sig);
if (ret == 0)
{
gnutls_assert ();
ret = GNUTLS_E_PK_SIGN_FAILED;
goto dsa_fail;
}
ret = _gnutls_encode_ber_rs (signature, &sig.r, &sig.s);
dsa_fail:
dsa_signature_clear (&sig);
if (ret < 0)
{
gnutls_assert ();
goto cleanup;
}
break;
}
case GNUTLS_PK_RSA:
{
struct rsa_private_key priv;
struct rsa_public_key pub;
mpz_t s;
_rsa_params_to_privkey (pk_params, &priv);
_rsa_params_to_pubkey (pk_params, &pub);
mpz_init(s);
ret = rsa_pkcs1_sign_tr(&pub, &priv, NULL, rnd_func,
vdata->size, vdata->data, s);
if (ret == 0)
{
gnutls_assert();
ret = GNUTLS_E_PK_SIGN_FAILED;
goto rsa_fail;
}
ret = _gnutls_mpi_dprint (s, signature);
rsa_fail:
mpz_clear(s);
if (ret < 0)
{
gnutls_assert ();
goto cleanup;
}
break;
}
default:
gnutls_assert ();
ret = GNUTLS_E_INTERNAL_ERROR;
goto cleanup;
}
ret = 0;
cleanup:
return ret;
}
static int
_wrap_nettle_pk_decrypt (gnutls_pk_algorithm_t algo,
gnutls_datum_t * plaintext,
const gnutls_datum_t * ciphertext,
const gnutls_pk_params_st * pk_params)
{
int ret;
plaintext->data = NULL;
/* make a sexp from pkey */
switch (algo)
{
case GNUTLS_PK_RSA:
{
struct rsa_private_key priv;
struct rsa_public_key pub;
unsigned length;
bigint_t c;
_rsa_params_to_privkey (pk_params, &priv);
_rsa_params_to_pubkey (pk_params, &pub);
if (_gnutls_mpi_scan_nz (&c, ciphertext->data, ciphertext->size) != 0)
{
ret = gnutls_assert_val(GNUTLS_E_MPI_SCAN_FAILED);
goto cleanup;
}
length = pub.size;
plaintext->data = gnutls_malloc(length);
if (plaintext->data == NULL)
{
ret = gnutls_assert_val(GNUTLS_E_MEMORY_ERROR);
goto cleanup;
}
ret = rsa_decrypt_tr(&pub, &priv, NULL, rnd_func, &length, plaintext->data,
TOMPZ(c));
_gnutls_mpi_release (&c);
plaintext->size = length;
if (ret == 0)
{
ret = gnutls_assert_val(GNUTLS_E_DECRYPTION_FAILED);
goto cleanup;
}
break;
}
default:
gnutls_assert ();
ret = GNUTLS_E_INTERNAL_ERROR;
goto cleanup;
}
ret = 0;
cleanup:
if (ret < 0)
gnutls_free(plaintext->data);
return ret;
}
/* Given a signature and parameters, it should return
* the hash algorithm used in the signature. This is a kludge
* but until we deprecate gnutls_pubkey_get_verify_algorithm()
* we depend on it.
*/
static int wrap_nettle_hash_algorithm (gnutls_pk_algorithm_t pk,
const gnutls_datum_t * sig, gnutls_pk_params_st * issuer_params,
gnutls_digest_algorithm_t* hash_algo)
{
uint8_t digest[MAX_HASH_SIZE];
uint8_t digest_info[MAX_HASH_SIZE*3];
gnutls_datum_t di;
unsigned digest_size;
mpz_t s;
struct rsa_public_key pub;
int ret;
mpz_init(s);
switch (pk)
{
case GNUTLS_PK_DSA:
case GNUTLS_PK_EC:
if (hash_algo)
*hash_algo = _gnutls_dsa_q_to_hash (pk, issuer_params, NULL);
ret = 0;
break;
case GNUTLS_PK_RSA:
if (sig == NULL)
{ /* return a sensible algorithm */
if (hash_algo)
*hash_algo = GNUTLS_DIG_SHA256;
return 0;
}
_rsa_params_to_pubkey (issuer_params, &pub);
digest_size = sizeof(digest);
nettle_mpz_set_str_256_u(s, sig->size, sig->data);
digest_size = sizeof (digest_info);
ret = extract_digest_info( &pub, &digest_size, digest_info, s);
if (ret == 0)
{
ret = GNUTLS_E_PK_SIG_VERIFY_FAILED;
gnutls_assert ();
goto cleanup;
}
di.data = digest_info;
di.size = digest_size;
digest_size = sizeof(digest);
if ((ret =
decode_ber_digest_info (&di, hash_algo, digest,
&digest_size)) < 0)
{
gnutls_assert ();
goto cleanup;
}
if (digest_size != _gnutls_hash_get_algo_len (*hash_algo))
{
gnutls_assert ();
ret = GNUTLS_E_PK_SIG_VERIFY_FAILED;
goto cleanup;
}
ret = 0;
break;
default:
gnutls_assert ();
ret = GNUTLS_E_INTERNAL_ERROR;
}
cleanup:
mpz_clear(s);
return ret;
}
