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Diffstat (limited to 'openssl/crypto/ec/ec_ameth.c')
-rw-r--r--openssl/crypto/ec/ec_ameth.c659
1 files changed, 659 insertions, 0 deletions
diff --git a/openssl/crypto/ec/ec_ameth.c b/openssl/crypto/ec/ec_ameth.c
new file mode 100644
index 00000000..c00f7d74
--- /dev/null
+++ b/openssl/crypto/ec/ec_ameth.c
@@ -0,0 +1,659 @@
+/* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
+ * project 2006.
+ */
+/* ====================================================================
+ * Copyright (c) 2006 The OpenSSL Project. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * 3. All advertising materials mentioning features or use of this
+ * software must display the following acknowledgment:
+ * "This product includes software developed by the OpenSSL Project
+ * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
+ *
+ * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
+ * endorse or promote products derived from this software without
+ * prior written permission. For written permission, please contact
+ * licensing@OpenSSL.org.
+ *
+ * 5. Products derived from this software may not be called "OpenSSL"
+ * nor may "OpenSSL" appear in their names without prior written
+ * permission of the OpenSSL Project.
+ *
+ * 6. Redistributions of any form whatsoever must retain the following
+ * acknowledgment:
+ * "This product includes software developed by the OpenSSL Project
+ * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
+ * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This product includes cryptographic software written by Eric Young
+ * (eay@cryptsoft.com). This product includes software written by Tim
+ * Hudson (tjh@cryptsoft.com).
+ *
+ */
+
+#include <stdio.h>
+#include "cryptlib.h"
+#include <openssl/x509.h>
+#include <openssl/ec.h>
+#include <openssl/bn.h>
+#ifndef OPENSSL_NO_CMS
+#include <openssl/cms.h>
+#endif
+#include "asn1_locl.h"
+
+static int eckey_param2type(int *pptype, void **ppval, EC_KEY *ec_key)
+ {
+ const EC_GROUP *group;
+ int nid;
+ if (ec_key == NULL || (group = EC_KEY_get0_group(ec_key)) == NULL)
+ {
+ ECerr(EC_F_ECKEY_PARAM2TYPE, EC_R_MISSING_PARAMETERS);
+ return 0;
+ }
+ if (EC_GROUP_get_asn1_flag(group)
+ && (nid = EC_GROUP_get_curve_name(group)))
+ /* we have a 'named curve' => just set the OID */
+ {
+ *ppval = OBJ_nid2obj(nid);
+ *pptype = V_ASN1_OBJECT;
+ }
+ else /* explicit parameters */
+ {
+ ASN1_STRING *pstr = NULL;
+ pstr = ASN1_STRING_new();
+ if (!pstr)
+ return 0;
+ pstr->length = i2d_ECParameters(ec_key, &pstr->data);
+ if (pstr->length < 0)
+ {
+ ASN1_STRING_free(pstr);
+ ECerr(EC_F_ECKEY_PARAM2TYPE, ERR_R_EC_LIB);
+ return 0;
+ }
+ *ppval = pstr;
+ *pptype = V_ASN1_SEQUENCE;
+ }
+ return 1;
+ }
+
+static int eckey_pub_encode(X509_PUBKEY *pk, const EVP_PKEY *pkey)
+ {
+ EC_KEY *ec_key = pkey->pkey.ec;
+ void *pval = NULL;
+ int ptype;
+ unsigned char *penc = NULL, *p;
+ int penclen;
+
+ if (!eckey_param2type(&ptype, &pval, ec_key))
+ {
+ ECerr(EC_F_ECKEY_PUB_ENCODE, ERR_R_EC_LIB);
+ return 0;
+ }
+ penclen = i2o_ECPublicKey(ec_key, NULL);
+ if (penclen <= 0)
+ goto err;
+ penc = OPENSSL_malloc(penclen);
+ if (!penc)
+ goto err;
+ p = penc;
+ penclen = i2o_ECPublicKey(ec_key, &p);
+ if (penclen <= 0)
+ goto err;
+ if (X509_PUBKEY_set0_param(pk, OBJ_nid2obj(EVP_PKEY_EC),
+ ptype, pval, penc, penclen))
+ return 1;
+ err:
+ if (ptype == V_ASN1_OBJECT)
+ ASN1_OBJECT_free(pval);
+ else
+ ASN1_STRING_free(pval);
+ if (penc)
+ OPENSSL_free(penc);
+ return 0;
+ }
+
+static EC_KEY *eckey_type2param(int ptype, void *pval)
+ {
+ EC_KEY *eckey = NULL;
+ if (ptype == V_ASN1_SEQUENCE)
+ {
+ ASN1_STRING *pstr = pval;
+ const unsigned char *pm = NULL;
+ int pmlen;
+ pm = pstr->data;
+ pmlen = pstr->length;
+ if (!(eckey = d2i_ECParameters(NULL, &pm, pmlen)))
+ {
+ ECerr(EC_F_ECKEY_TYPE2PARAM, EC_R_DECODE_ERROR);
+ goto ecerr;
+ }
+ }
+ else if (ptype == V_ASN1_OBJECT)
+ {
+ ASN1_OBJECT *poid = pval;
+ EC_GROUP *group;
+
+ /* type == V_ASN1_OBJECT => the parameters are given
+ * by an asn1 OID
+ */
+ if ((eckey = EC_KEY_new()) == NULL)
+ {
+ ECerr(EC_F_ECKEY_TYPE2PARAM, ERR_R_MALLOC_FAILURE);
+ goto ecerr;
+ }
+ group = EC_GROUP_new_by_curve_name(OBJ_obj2nid(poid));
+ if (group == NULL)
+ goto ecerr;
+ EC_GROUP_set_asn1_flag(group, OPENSSL_EC_NAMED_CURVE);
+ if (EC_KEY_set_group(eckey, group) == 0)
+ goto ecerr;
+ EC_GROUP_free(group);
+ }
+ else
+ {
+ ECerr(EC_F_ECKEY_TYPE2PARAM, EC_R_DECODE_ERROR);
+ goto ecerr;
+ }
+
+ return eckey;
+
+ ecerr:
+ if (eckey)
+ EC_KEY_free(eckey);
+ return NULL;
+ }
+
+static int eckey_pub_decode(EVP_PKEY *pkey, X509_PUBKEY *pubkey)
+ {
+ const unsigned char *p = NULL;
+ void *pval;
+ int ptype, pklen;
+ EC_KEY *eckey = NULL;
+ X509_ALGOR *palg;
+
+ if (!X509_PUBKEY_get0_param(NULL, &p, &pklen, &palg, pubkey))
+ return 0;
+ X509_ALGOR_get0(NULL, &ptype, &pval, palg);
+
+ eckey = eckey_type2param(ptype, pval);
+
+ if (!eckey)
+ {
+ ECerr(EC_F_ECKEY_PUB_DECODE, ERR_R_EC_LIB);
+ return 0;
+ }
+
+ /* We have parameters now set public key */
+ if (!o2i_ECPublicKey(&eckey, &p, pklen))
+ {
+ ECerr(EC_F_ECKEY_PUB_DECODE, EC_R_DECODE_ERROR);
+ goto ecerr;
+ }
+
+ EVP_PKEY_assign_EC_KEY(pkey, eckey);
+ return 1;
+
+ ecerr:
+ if (eckey)
+ EC_KEY_free(eckey);
+ return 0;
+ }
+
+static int eckey_pub_cmp(const EVP_PKEY *a, const EVP_PKEY *b)
+ {
+ int r;
+ const EC_GROUP *group = EC_KEY_get0_group(b->pkey.ec);
+ const EC_POINT *pa = EC_KEY_get0_public_key(a->pkey.ec),
+ *pb = EC_KEY_get0_public_key(b->pkey.ec);
+ r = EC_POINT_cmp(group, pa, pb, NULL);
+ if (r == 0)
+ return 1;
+ if (r == 1)
+ return 0;
+ return -2;
+ }
+
+static int eckey_priv_decode(EVP_PKEY *pkey, PKCS8_PRIV_KEY_INFO *p8)
+ {
+ const unsigned char *p = NULL;
+ void *pval;
+ int ptype, pklen;
+ EC_KEY *eckey = NULL;
+ X509_ALGOR *palg;
+
+ if (!PKCS8_pkey_get0(NULL, &p, &pklen, &palg, p8))
+ return 0;
+ X509_ALGOR_get0(NULL, &ptype, &pval, palg);
+
+ eckey = eckey_type2param(ptype, pval);
+
+ if (!eckey)
+ goto ecliberr;
+
+ /* We have parameters now set private key */
+ if (!d2i_ECPrivateKey(&eckey, &p, pklen))
+ {
+ ECerr(EC_F_ECKEY_PRIV_DECODE, EC_R_DECODE_ERROR);
+ goto ecerr;
+ }
+
+ /* calculate public key (if necessary) */
+ if (EC_KEY_get0_public_key(eckey) == NULL)
+ {
+ const BIGNUM *priv_key;
+ const EC_GROUP *group;
+ EC_POINT *pub_key;
+ /* the public key was not included in the SEC1 private
+ * key => calculate the public key */
+ group = EC_KEY_get0_group(eckey);
+ pub_key = EC_POINT_new(group);
+ if (pub_key == NULL)
+ {
+ ECerr(EC_F_ECKEY_PRIV_DECODE, ERR_R_EC_LIB);
+ goto ecliberr;
+ }
+ if (!EC_POINT_copy(pub_key, EC_GROUP_get0_generator(group)))
+ {
+ EC_POINT_free(pub_key);
+ ECerr(EC_F_ECKEY_PRIV_DECODE, ERR_R_EC_LIB);
+ goto ecliberr;
+ }
+ priv_key = EC_KEY_get0_private_key(eckey);
+ if (!EC_POINT_mul(group, pub_key, priv_key, NULL, NULL, NULL))
+ {
+ EC_POINT_free(pub_key);
+ ECerr(EC_F_ECKEY_PRIV_DECODE, ERR_R_EC_LIB);
+ goto ecliberr;
+ }
+ if (EC_KEY_set_public_key(eckey, pub_key) == 0)
+ {
+ EC_POINT_free(pub_key);
+ ECerr(EC_F_ECKEY_PRIV_DECODE, ERR_R_EC_LIB);
+ goto ecliberr;
+ }
+ EC_POINT_free(pub_key);
+ }
+
+ EVP_PKEY_assign_EC_KEY(pkey, eckey);
+ return 1;
+
+ ecliberr:
+ ECerr(EC_F_ECKEY_PRIV_DECODE, ERR_R_EC_LIB);
+ ecerr:
+ if (eckey)
+ EC_KEY_free(eckey);
+ return 0;
+ }
+
+static int eckey_priv_encode(PKCS8_PRIV_KEY_INFO *p8, const EVP_PKEY *pkey)
+{
+ EC_KEY *ec_key;
+ unsigned char *ep, *p;
+ int eplen, ptype;
+ void *pval;
+ unsigned int tmp_flags, old_flags;
+
+ ec_key = pkey->pkey.ec;
+
+ if (!eckey_param2type(&ptype, &pval, ec_key))
+ {
+ ECerr(EC_F_ECKEY_PRIV_ENCODE, EC_R_DECODE_ERROR);
+ return 0;
+ }
+
+ /* set the private key */
+
+ /* do not include the parameters in the SEC1 private key
+ * see PKCS#11 12.11 */
+ old_flags = EC_KEY_get_enc_flags(ec_key);
+ tmp_flags = old_flags | EC_PKEY_NO_PARAMETERS;
+ EC_KEY_set_enc_flags(ec_key, tmp_flags);
+ eplen = i2d_ECPrivateKey(ec_key, NULL);
+ if (!eplen)
+ {
+ EC_KEY_set_enc_flags(ec_key, old_flags);
+ ECerr(EC_F_ECKEY_PRIV_ENCODE, ERR_R_EC_LIB);
+ return 0;
+ }
+ ep = (unsigned char *) OPENSSL_malloc(eplen);
+ if (!ep)
+ {
+ EC_KEY_set_enc_flags(ec_key, old_flags);
+ ECerr(EC_F_ECKEY_PRIV_ENCODE, ERR_R_MALLOC_FAILURE);
+ return 0;
+ }
+ p = ep;
+ if (!i2d_ECPrivateKey(ec_key, &p))
+ {
+ EC_KEY_set_enc_flags(ec_key, old_flags);
+ OPENSSL_free(ep);
+ ECerr(EC_F_ECKEY_PRIV_ENCODE, ERR_R_EC_LIB);
+ }
+ /* restore old encoding flags */
+ EC_KEY_set_enc_flags(ec_key, old_flags);
+
+ if (!PKCS8_pkey_set0(p8, OBJ_nid2obj(NID_X9_62_id_ecPublicKey), 0,
+ ptype, pval, ep, eplen))
+ return 0;
+
+ return 1;
+}
+
+static int int_ec_size(const EVP_PKEY *pkey)
+ {
+ return ECDSA_size(pkey->pkey.ec);
+ }
+
+static int ec_bits(const EVP_PKEY *pkey)
+ {
+ BIGNUM *order = BN_new();
+ const EC_GROUP *group;
+ int ret;
+
+ if (!order)
+ {
+ ERR_clear_error();
+ return 0;
+ }
+ group = EC_KEY_get0_group(pkey->pkey.ec);
+ if (!EC_GROUP_get_order(group, order, NULL))
+ {
+ ERR_clear_error();
+ return 0;
+ }
+
+ ret = BN_num_bits(order);
+ BN_free(order);
+ return ret;
+ }
+
+static int ec_missing_parameters(const EVP_PKEY *pkey)
+ {
+ if (EC_KEY_get0_group(pkey->pkey.ec) == NULL)
+ return 1;
+ return 0;
+ }
+
+static int ec_copy_parameters(EVP_PKEY *to, const EVP_PKEY *from)
+ {
+ EC_GROUP *group = EC_GROUP_dup(EC_KEY_get0_group(from->pkey.ec));
+ if (group == NULL)
+ return 0;
+ if (EC_KEY_set_group(to->pkey.ec, group) == 0)
+ return 0;
+ EC_GROUP_free(group);
+ return 1;
+ }
+
+static int ec_cmp_parameters(const EVP_PKEY *a, const EVP_PKEY *b)
+ {
+ const EC_GROUP *group_a = EC_KEY_get0_group(a->pkey.ec),
+ *group_b = EC_KEY_get0_group(b->pkey.ec);
+ if (EC_GROUP_cmp(group_a, group_b, NULL))
+ return 0;
+ else
+ return 1;
+ }
+
+static void int_ec_free(EVP_PKEY *pkey)
+ {
+ EC_KEY_free(pkey->pkey.ec);
+ }
+
+static int do_EC_KEY_print(BIO *bp, const EC_KEY *x, int off, int ktype)
+ {
+ unsigned char *buffer=NULL;
+ const char *ecstr;
+ size_t buf_len=0, i;
+ int ret=0, reason=ERR_R_BIO_LIB;
+ BIGNUM *pub_key=NULL, *order=NULL;
+ BN_CTX *ctx=NULL;
+ const EC_GROUP *group;
+ const EC_POINT *public_key;
+ const BIGNUM *priv_key;
+
+ if (x == NULL || (group = EC_KEY_get0_group(x)) == NULL)
+ {
+ reason = ERR_R_PASSED_NULL_PARAMETER;
+ goto err;
+ }
+
+ ctx = BN_CTX_new();
+ if (ctx == NULL)
+ {
+ reason = ERR_R_MALLOC_FAILURE;
+ goto err;
+ }
+
+ if (ktype > 0)
+ {
+ public_key = EC_KEY_get0_public_key(x);
+ if ((pub_key = EC_POINT_point2bn(group, public_key,
+ EC_KEY_get_conv_form(x), NULL, ctx)) == NULL)
+ {
+ reason = ERR_R_EC_LIB;
+ goto err;
+ }
+ if (pub_key)
+ buf_len = (size_t)BN_num_bytes(pub_key);
+ }
+
+ if (ktype == 2)
+ {
+ priv_key = EC_KEY_get0_private_key(x);
+ if (priv_key && (i = (size_t)BN_num_bytes(priv_key)) > buf_len)
+ buf_len = i;
+ }
+ else
+ priv_key = NULL;
+
+ if (ktype > 0)
+ {
+ buf_len += 10;
+ if ((buffer = OPENSSL_malloc(buf_len)) == NULL)
+ {
+ reason = ERR_R_MALLOC_FAILURE;
+ goto err;
+ }
+ }
+ if (ktype == 2)
+ ecstr = "Private-Key";
+ else if (ktype == 1)
+ ecstr = "Public-Key";
+ else
+ ecstr = "ECDSA-Parameters";
+
+ if (!BIO_indent(bp, off, 128))
+ goto err;
+ if ((order = BN_new()) == NULL)
+ goto err;
+ if (!EC_GROUP_get_order(group, order, NULL))
+ goto err;
+ if (BIO_printf(bp, "%s: (%d bit)\n", ecstr,
+ BN_num_bits(order)) <= 0) goto err;
+
+ if ((priv_key != NULL) && !ASN1_bn_print(bp, "priv:", priv_key,
+ buffer, off))
+ goto err;
+ if ((pub_key != NULL) && !ASN1_bn_print(bp, "pub: ", pub_key,
+ buffer, off))
+ goto err;
+ if (!ECPKParameters_print(bp, group, off))
+ goto err;
+ ret=1;
+err:
+ if (!ret)
+ ECerr(EC_F_DO_EC_KEY_PRINT, reason);
+ if (pub_key)
+ BN_free(pub_key);
+ if (order)
+ BN_free(order);
+ if (ctx)
+ BN_CTX_free(ctx);
+ if (buffer != NULL)
+ OPENSSL_free(buffer);
+ return(ret);
+ }
+
+static int eckey_param_decode(EVP_PKEY *pkey,
+ const unsigned char **pder, int derlen)
+ {
+ EC_KEY *eckey;
+ if (!(eckey = d2i_ECParameters(NULL, pder, derlen)))
+ {
+ ECerr(EC_F_ECKEY_PARAM_DECODE, ERR_R_EC_LIB);
+ return 0;
+ }
+ EVP_PKEY_assign_EC_KEY(pkey, eckey);
+ return 1;
+ }
+
+static int eckey_param_encode(const EVP_PKEY *pkey, unsigned char **pder)
+ {
+ return i2d_ECParameters(pkey->pkey.ec, pder);
+ }
+
+static int eckey_param_print(BIO *bp, const EVP_PKEY *pkey, int indent,
+ ASN1_PCTX *ctx)
+ {
+ return do_EC_KEY_print(bp, pkey->pkey.ec, indent, 0);
+ }
+
+static int eckey_pub_print(BIO *bp, const EVP_PKEY *pkey, int indent,
+ ASN1_PCTX *ctx)
+ {
+ return do_EC_KEY_print(bp, pkey->pkey.ec, indent, 1);
+ }
+
+
+static int eckey_priv_print(BIO *bp, const EVP_PKEY *pkey, int indent,
+ ASN1_PCTX *ctx)
+ {
+ return do_EC_KEY_print(bp, pkey->pkey.ec, indent, 2);
+ }
+
+static int old_ec_priv_decode(EVP_PKEY *pkey,
+ const unsigned char **pder, int derlen)
+ {
+ EC_KEY *ec;
+ if (!(ec = d2i_ECPrivateKey (NULL, pder, derlen)))
+ {
+ ECerr(EC_F_OLD_EC_PRIV_DECODE, EC_R_DECODE_ERROR);
+ return 0;
+ }
+ EVP_PKEY_assign_EC_KEY(pkey, ec);
+ return 1;
+ }
+
+static int old_ec_priv_encode(const EVP_PKEY *pkey, unsigned char **pder)
+ {
+ return i2d_ECPrivateKey(pkey->pkey.ec, pder);
+ }
+
+static int ec_pkey_ctrl(EVP_PKEY *pkey, int op, long arg1, void *arg2)
+ {
+ switch (op)
+ {
+ case ASN1_PKEY_CTRL_PKCS7_SIGN:
+ if (arg1 == 0)
+ {
+ int snid, hnid;
+ X509_ALGOR *alg1, *alg2;
+ PKCS7_SIGNER_INFO_get0_algs(arg2, NULL, &alg1, &alg2);
+ if (alg1 == NULL || alg1->algorithm == NULL)
+ return -1;
+ hnid = OBJ_obj2nid(alg1->algorithm);
+ if (hnid == NID_undef)
+ return -1;
+ if (!OBJ_find_sigid_by_algs(&snid, hnid, EVP_PKEY_id(pkey)))
+ return -1;
+ X509_ALGOR_set0(alg2, OBJ_nid2obj(snid), V_ASN1_UNDEF, 0);
+ }
+ return 1;
+#ifndef OPENSSL_NO_CMS
+ case ASN1_PKEY_CTRL_CMS_SIGN:
+ if (arg1 == 0)
+ {
+ int snid, hnid;
+ X509_ALGOR *alg1, *alg2;
+ CMS_SignerInfo_get0_algs(arg2, NULL, NULL,
+ &alg1, &alg2);
+ if (alg1 == NULL || alg1->algorithm == NULL)
+ return -1;
+ hnid = OBJ_obj2nid(alg1->algorithm);
+ if (hnid == NID_undef)
+ return -1;
+ if (!OBJ_find_sigid_by_algs(&snid, hnid, EVP_PKEY_id(pkey)))
+ return -1;
+ X509_ALGOR_set0(alg2, OBJ_nid2obj(snid), V_ASN1_UNDEF, 0);
+ }
+ return 1;
+#endif
+
+ case ASN1_PKEY_CTRL_DEFAULT_MD_NID:
+ *(int *)arg2 = NID_sha1;
+ return 2;
+
+ default:
+ return -2;
+
+ }
+
+ }
+
+const EVP_PKEY_ASN1_METHOD eckey_asn1_meth =
+ {
+ EVP_PKEY_EC,
+ EVP_PKEY_EC,
+ 0,
+ "EC",
+ "OpenSSL EC algorithm",
+
+ eckey_pub_decode,
+ eckey_pub_encode,
+ eckey_pub_cmp,
+ eckey_pub_print,
+
+ eckey_priv_decode,
+ eckey_priv_encode,
+ eckey_priv_print,
+
+ int_ec_size,
+ ec_bits,
+
+ eckey_param_decode,
+ eckey_param_encode,
+ ec_missing_parameters,
+ ec_copy_parameters,
+ ec_cmp_parameters,
+ eckey_param_print,
+
+ int_ec_free,
+ ec_pkey_ctrl,
+ old_ec_priv_decode,
+ old_ec_priv_encode
+ };
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