1 files changed, 139 insertions, 92 deletions

diff --git a/src/lib/libcrypto/ec/ec_ameth.c b/src/lib/libcrypto/ec/ec_ameth.c
index f2ad5f60c6..258daec127 100644
--- a/src/lib/libcrypto/ec/ec_ameth.c
+++ b/src/lib/libcrypto/ec/ec_ameth.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ec_ameth.c,v 1.43 2023/08/21 09:52:30 tb Exp $ */
+/* $OpenBSD: ec_ameth.c,v 1.44 2023/09/24 07:58:31 tb Exp $ */
 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
  * project 2006.
  */
@@ -87,38 +87,136 @@ eckey_param_free(int ptype, void *pval)
 }
 
 static int
-eckey_param2type(int *pptype, void **ppval, EC_KEY *ec_key)
+eckey_get_curve_name(const EC_KEY *eckey, int *nid)
 {
         const EC_GROUP *group;
-        int nid;
-        if (ec_key == NULL || (group = EC_KEY_get0_group(ec_key)) == NULL) {
+
+        *nid = NID_undef;
+
+        if ((group = EC_KEY_get0_group(eckey)) == NULL) {
                 ECerror(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);
-                        ECerror(ERR_R_EC_LIB);
-                        return 0;
-                }
-                *ppval = pstr;
-                *pptype = V_ASN1_SEQUENCE;
+        if (EC_GROUP_get_asn1_flag(group) != 0)
+                *nid = EC_GROUP_get_curve_name(group);
+
+        return 1;
+}
+
+static int
+eckey_to_explicit_params(EC_KEY *eckey, void **out_val)
+{
+        ASN1_STRING *astr = NULL;
+        unsigned char *params = NULL;
+        int params_len = 0;
+        int ret = 0;
+
+        *out_val = NULL;
+
+        if ((params_len = i2d_ECParameters(eckey, &params)) <= 0) {
+                ECerror(ERR_R_EC_LIB);
+                params_len = 0;
+                goto err;
+        }
+
+        if ((astr = ASN1_STRING_new()) == NULL)
+                goto err;
+        ASN1_STRING_set0(astr, params, params_len);
+        params = NULL;
+        params_len = 0;
+
+        *out_val = astr;
+        astr = NULL;
+
+        ret = 1;
+
+ err:
+        freezero(params, params_len);
+        ASN1_STRING_free(astr);
+
+        return ret;
+}
+
+static int
+eckey_from_explicit_params(const ASN1_STRING *astr, EC_KEY **out_eckey)
+{
+        const unsigned char *params = astr->data;
+        int params_len = astr->length;
+
+        EC_KEY_free(*out_eckey);
+        if ((*out_eckey = d2i_ECParameters(NULL, &params, params_len)) == NULL) {
+                ECerror(EC_R_DECODE_ERROR);
+                return 0;
         }
+
+        return 1;
+}
+
+static int
+eckey_to_object(const EC_KEY *eckey, void **out_val)
+{
+        int nid = NID_undef;
+
+        *out_val = NULL;
+
+        if (!eckey_get_curve_name(eckey, &nid))
+                return 0;
+        if ((*out_val = OBJ_nid2obj(nid)) == NULL)
+                return 0;
+
         return 1;
 }
 
 static int
+eckey_from_object(const ASN1_OBJECT *aobj, EC_KEY **out_eckey)
+{
+        int nid;
+
+        *out_eckey = NULL;
+
+        if ((nid = OBJ_obj2nid(aobj)) == NID_undef)
+                return 0;
+        if ((*out_eckey = EC_KEY_new_by_curve_name(nid)) == NULL)
+                return 0;
+
+        return 1;
+}
+
+static int
+eckey_to_params(EC_KEY *eckey, int *out_type, void **out_val)
+{
+        int nid;
+
+        *out_type = NID_undef;
+        *out_val = NULL;
+
+        if (!eckey_get_curve_name(eckey, &nid))
+                return 0;
+
+        if (nid == NID_undef) {
+                *out_type = V_ASN1_SEQUENCE;
+                return eckey_to_explicit_params(eckey, out_val);
+        } else {
+                *out_type = V_ASN1_OBJECT;
+                return eckey_to_object(eckey, out_val);
+        }
+}
+
+static int
+eckey_from_params(int ptype, const void *pval, EC_KEY **out_eckey)
+{
+        *out_eckey = NULL;
+
+        if (ptype == V_ASN1_SEQUENCE)
+                return eckey_from_explicit_params(pval, out_eckey);
+        if (ptype == V_ASN1_OBJECT)
+                return eckey_from_object(pval, out_eckey);
+
+        ECerror(EC_R_DECODE_ERROR);
+        return 0;
+}
+
+static int
 eckey_pub_encode(X509_PUBKEY *pk, const EVP_PKEY *pkey)
 {
         EC_KEY *eckey = pkey->pkey.ec;
@@ -129,7 +227,7 @@ eckey_pub_encode(X509_PUBKEY *pk, const EVP_PKEY *pkey)
         int key_len = 0;
         int ret = 0;
 
-        if (!eckey_param2type(&ptype, &pval, eckey)) {
+        if (!eckey_to_params(eckey, &ptype, &pval)) {
                 ECerror(ERR_R_EC_LIB);
                 goto err;
         }
@@ -154,54 +252,6 @@ eckey_pub_encode(X509_PUBKEY *pk, const EVP_PKEY *pkey)
         return ret;
 }
 
-static EC_KEY *
-eckey_type2param(int ptype, const void *pval)
-{
-        EC_GROUP *group = NULL;
-        EC_KEY *eckey = NULL;
-
-        if (ptype == V_ASN1_SEQUENCE) {
-                const ASN1_STRING *pstr = pval;
-                const unsigned char *pm = NULL;
-                int pmlen;
-
-                pm = pstr->data;
-                pmlen = pstr->length;
-                if (!(eckey = d2i_ECParameters(NULL, &pm, pmlen))) {
-                        ECerror(EC_R_DECODE_ERROR);
-                        goto ecerr;
-                }
-        } else if (ptype == V_ASN1_OBJECT) {
-                const ASN1_OBJECT *poid = pval;
-
-                /*
-                 * type == V_ASN1_OBJECT => the parameters are given by an
-                 * asn1 OID
-                 */
-                if ((eckey = EC_KEY_new()) == NULL) {
-                        ECerror(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;
-        } else {
-                ECerror(EC_R_DECODE_ERROR);
-                goto ecerr;
-        }
-
-        EC_GROUP_free(group);
-        return eckey;
-
- ecerr:
-        EC_KEY_free(eckey);
-        EC_GROUP_free(group);
-        return NULL;
-}
-
 static int
 eckey_pub_decode(EVP_PKEY *pkey, X509_PUBKEY *pubkey)
 {
@@ -210,29 +260,29 @@ eckey_pub_decode(EVP_PKEY *pkey, X509_PUBKEY *pubkey)
         int ptype, pklen;
         EC_KEY *eckey = NULL;
         X509_ALGOR *palg;
+        int ret = 0;
 
         if (!X509_PUBKEY_get0_param(NULL, &p, &pklen, &palg, pubkey))
-                return 0;
+                goto err;
         X509_ALGOR_get0(NULL, &ptype, &pval, palg);
 
-        eckey = eckey_type2param(ptype, pval);
+        if (!eckey_from_params(ptype, pval, &eckey))
+                goto err;
 
-        if (!eckey) {
-                ECerror(ERR_R_EC_LIB);
-                return 0;
-        }
-        /* We have parameters now set public key */
         if (!o2i_ECPublicKey(&eckey, &p, pklen)) {
                 ECerror(EC_R_DECODE_ERROR);
-                goto ecerr;
+                goto err;
         }
-        EVP_PKEY_assign_EC_KEY(pkey, eckey);
-        return 1;
+        if (!EVP_PKEY_assign_EC_KEY(pkey, eckey))
+                goto err;
+        eckey = NULL;
 
- ecerr:
-        if (eckey)
-                EC_KEY_free(eckey);
-        return 0;
+        ret = 1;
+
+ err:
+        EC_KEY_free(eckey);
+
+        return ret;
 }
 
 static int
@@ -263,9 +313,7 @@ eckey_priv_decode(EVP_PKEY *pkey, const PKCS8_PRIV_KEY_INFO *p8)
                 return 0;
         X509_ALGOR_get0(NULL, &ptype, &pval, palg);
 
-        eckey = eckey_type2param(ptype, pval);
-
-        if (!eckey)
+        if (!eckey_from_params(ptype, pval, &eckey))
                 goto ecliberr;
 
         /* We have parameters now set private key */
@@ -331,7 +379,7 @@ eckey_priv_encode(PKCS8_PRIV_KEY_INFO *p8, const EVP_PKEY *pkey)
 
         flags = EC_KEY_get_enc_flags(eckey);
 
-        if (!eckey_param2type(&ptype, &pval, eckey)) {
+        if (!eckey_to_params(eckey, &ptype, &pval)) {
                 ECerror(EC_R_DECODE_ERROR);
                 goto err;
         }
@@ -685,8 +733,7 @@ ecdh_cms_set_peerkey(EVP_PKEY_CTX *pctx, X509_ALGOR *alg,
                 if (!EC_KEY_set_group(ecpeer, grp))
                         goto err;
         } else {
-                ecpeer = eckey_type2param(atype, aval);
-                if (!ecpeer)
+                if (!eckey_from_params(atype, aval, &ecpeer))
                         goto err;
         }