less specific interface for EC_GROUP_get_basis_type

Submitted by: Nils Larsch, Bodo Moeller

4 files changed, 72 insertions, 27 deletions

diff --git a/crypto/ec/ec.h b/crypto/ec/ec.h
index e401eb739c..faca04aab9 100644
--- a/crypto/ec/ec.h
+++ b/crypto/ec/ec.h
@@ -257,9 +257,10 @@ int EC_GROUP_precompute_mult(EC_GROUP *, BN_CTX *);
 /* ASN1 stuff */
 
 /* EC_GROUP_get_basis_type() returns the NID of the basis type
- * used to represent the field elements (in case of a pentanomial or trinomial
- * basis the coefficient are returned in the k? arguments) */
-int EC_GROUP_get_basis_type(const EC_GROUP *, unsigned int *k1,
+ * used to represent the field elements */
+int EC_GROUP_get_basis_type(const EC_GROUP *);
+int EC_GROUP_get_trinomial_basis(const EC_GROUP *, unsigned int *k);
+int EC_GROUP_get_pentanomial_basis(const EC_GROUP *, unsigned int *k1, 
 	unsigned int *k2, unsigned int *k3);
 
 #define OPENSSL_EC_NAMED_CURVE	0x001
@@ -372,6 +373,7 @@ void ERR_load_EC_strings(void);
 #define EC_F_EC_ASN1_PARAMETERS2GROUP			 157
 #define EC_F_EC_ASN1_PKPARAMETERS2GROUP			 158
 #define EC_F_EC_GF2M_SIMPLE_GROUP_CHECK_DISCRIMINANT	 159
+#define EC_F_EC_GF2M_SIMPLE_GROUP_SET_CURVE		 195
 #define EC_F_EC_GF2M_SIMPLE_OCT2POINT			 160
 #define EC_F_EC_GF2M_SIMPLE_POINT2OCT			 161
 #define EC_F_EC_GF2M_SIMPLE_POINT_GET_AFFINE_COORDINATES 162
@@ -405,6 +407,8 @@ void ERR_load_EC_strings(void);
 #define EC_F_EC_GROUP_GET_DEGREE			 173
 #define EC_F_EC_GROUP_GET_EXTRA_DATA			 107
 #define EC_F_EC_GROUP_GET_ORDER				 141
+#define EC_F_EC_GROUP_GET_PENTANOMIAL_BASIS		 193
+#define EC_F_EC_GROUP_GET_TRINOMIAL_BASIS		 194
 #define EC_F_EC_GROUP_GROUP2NID				 147
 #define EC_F_EC_GROUP_NEW				 108
 #define EC_F_EC_GROUP_NEW_BY_NID			 174
@@ -481,6 +485,7 @@ void ERR_load_EC_strings(void);
 #define EC_R_UNDEFINED_ORDER				 128
 #define EC_R_UNKNOWN_GROUP				 129
 #define EC_R_UNKNOWN_ORDER				 114
+#define EC_R_UNSUPPORTED_FIELD				 131
 #define EC_R_WRONG_ORDER				 130
 
 #ifdef  __cplusplus
diff --git a/crypto/ec/ec2_smpl.c b/crypto/ec/ec2_smpl.c
index 980d396c81..ece8abb8f6 100644
--- a/crypto/ec/ec2_smpl.c
+++ b/crypto/ec/ec2_smpl.c
@@ -200,7 +200,11 @@ int ec_GF2m_simple_group_set_curve(EC_GROUP *group,
 	/* group->field */
 	if (!BN_copy(&group->field, p)) goto err;
 	i = BN_GF2m_poly2arr(&group->field, group->poly, 5);
-	if ((i != 5) && (i != 3)) goto err;
+	if ((i != 5) && (i != 3))
+		{
+		ECerr(EC_F_EC_GF2M_SIMPLE_GROUP_SET_CURVE, EC_R_UNSUPPORTED_FIELD);
+		goto err;
+		}
 
 	/* group->a */
 	if (!BN_GF2m_mod_arr(&group->a, a, group->poly)) goto err;
diff --git a/crypto/ec/ec_asn1.c b/crypto/ec/ec_asn1.c
index 8b0167bd60..63d33a5f56 100644
--- a/crypto/ec/ec_asn1.c
+++ b/crypto/ec/ec_asn1.c
@@ -63,13 +63,9 @@
 #include <openssl/objects.h>
 
 
-int EC_GROUP_get_basis_type(const EC_GROUP *group, unsigned int *k1, 
-	unsigned int *k2, unsigned int *k3)
+int EC_GROUP_get_basis_type(const EC_GROUP *group)
 	{
-	int i = 0;
-
-	if (group == NULL)
-		return 0;
+	int i=0;
 
 	if (EC_METHOD_get_field_type(EC_GROUP_method_of(group)) !=
 		NID_X9_62_characteristic_two_field)
@@ -80,28 +76,55 @@ int EC_GROUP_get_basis_type(const EC_GROUP *group, unsigned int *k1,
 		i++;
 
 	if (i == 4)
-		{
-		if (k1)
-			*k1 = group->poly[3];
-		if (k2)
-			*k2 = group->poly[2];
-		if (k3)
-			*k3 = group->poly[1];
-
 		return NID_X9_62_ppBasis;
-		}
 	else if (i == 2)
-		{
-		if (k1)
-			*k1 = group->poly[1];
-
 		return NID_X9_62_tpBasis;
-		}
 	else
 		/* everything else is currently not supported */
 		return 0;
 	}
 
+int EC_GROUP_get_trinomial_basis(const EC_GROUP *group, unsigned int *k)
+	{
+	if (group == NULL)
+		return 0;
+
+	if (EC_GROUP_method_of(group)->group_set_curve != ec_GF2m_simple_group_set_curve
+	    || !((group->poly[0] != 0) && (group->poly[1] != 0) && (group->poly[2] == 0)))
+		{
+		ECerr(EC_F_EC_GROUP_GET_TRINOMIAL_BASIS, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
+		return 0;
+		}
+
+	if (k)
+		*k = group->poly[1];
+
+	return 1;
+	}
+
+int EC_GROUP_get_pentanomial_basis(const EC_GROUP *group, unsigned int *k1,
+	unsigned int *k2, unsigned int *k3)
+	{
+	if (group == NULL)
+		return 0;
+
+	if (EC_GROUP_method_of(group)->group_set_curve != ec_GF2m_simple_group_set_curve
+	    || !((group->poly[0] != 0) && (group->poly[1] != 0) && (group->poly[2] != 0) && (group->poly[3] != 0) && (group->poly[4] == 0)))
+		{
+		ECerr(EC_F_EC_GROUP_GET_PENTANOMIAL_BASIS, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
+		return 0;
+		}
+
+	if (k1)
+		*k1 = group->poly[3];
+	if (k2)
+		*k2 = group->poly[2];
+	if (k3)
+		*k3 = group->poly[1];
+
+	return 1;
+	}
+
 
 
 /* some structures needed for the asn1 encoding */
@@ -323,7 +346,6 @@ static X9_62_FIELDID *ec_asn1_group2field(const EC_GROUP *group,
 	else	/* nid == NID_X9_62_characteristic_two_field */
 		{
 		int		field_type;
-		unsigned int	k1, k2, k3;
 
 		char_two = X9_62_CHARACTERISTIC_TWO_new();
 		if (char_two == NULL)
@@ -334,7 +356,7 @@ static X9_62_FIELDID *ec_asn1_group2field(const EC_GROUP *group,
 	
 		char_two->m = (long)EC_GROUP_get_degree(group);
 
-		field_type = EC_GROUP_get_basis_type(group, &k1, &k2, &k3);
+		field_type = EC_GROUP_get_basis_type(group);
 
 		if (field_type == 0)
 			{
@@ -350,6 +372,11 @@ static X9_62_FIELDID *ec_asn1_group2field(const EC_GROUP *group,
 
 		if (field_type == NID_X9_62_tpBasis)
 			{
+			unsigned int k;
+
+			if (!EC_GROUP_get_trinomial_basis(group, &k))
+				goto err;
+
 			char_two->parameters->type = V_ASN1_INTEGER;
 			char_two->parameters->value.integer = 
 				ASN1_INTEGER_new();
@@ -359,7 +386,7 @@ static X9_62_FIELDID *ec_asn1_group2field(const EC_GROUP *group,
 					ERR_R_ASN1_LIB);
 				goto err;
 				}
-			if (!ASN1_INTEGER_set(char_two->parameters->value.integer, (long)k1))
+			if (!ASN1_INTEGER_set(char_two->parameters->value.integer, (long)k))
 				{
 				ECerr(EC_F_EC_ASN1_GROUP2PARAMETERS,
 					ERR_R_ASN1_LIB);
@@ -368,6 +395,11 @@ static X9_62_FIELDID *ec_asn1_group2field(const EC_GROUP *group,
 			}
 		else if (field_type == NID_X9_62_ppBasis)
 			{
+			unsigned int k1, k2, k3;
+
+			if (!EC_GROUP_get_pentanomial_basis(group, &k1, &k2, &k3))
+				goto err;
+
 			penta = X9_62_PENTANOMIAL_new();
 			/* set k? values */
 			penta->k1 = (long)k1;
diff --git a/crypto/ec/ec_err.c b/crypto/ec/ec_err.c
index 3a0f3f10e8..8ae2c00e32 100644
--- a/crypto/ec/ec_err.c
+++ b/crypto/ec/ec_err.c
@@ -83,6 +83,7 @@ static ERR_STRING_DATA EC_str_functs[]=
 {ERR_PACK(0,EC_F_EC_ASN1_PARAMETERS2GROUP,0),	"EC_ASN1_PARAMETERS2GROUP"},
 {ERR_PACK(0,EC_F_EC_ASN1_PKPARAMETERS2GROUP,0),	"EC_ASN1_PKPARAMETERS2GROUP"},
 {ERR_PACK(0,EC_F_EC_GF2M_SIMPLE_GROUP_CHECK_DISCRIMINANT,0),	"ec_GF2m_simple_group_check_discriminant"},
+{ERR_PACK(0,EC_F_EC_GF2M_SIMPLE_GROUP_SET_CURVE,0),	"ec_GF2m_simple_group_set_curve"},
 {ERR_PACK(0,EC_F_EC_GF2M_SIMPLE_OCT2POINT,0),	"ec_GF2m_simple_oct2point"},
 {ERR_PACK(0,EC_F_EC_GF2M_SIMPLE_POINT2OCT,0),	"ec_GF2m_simple_point2oct"},
 {ERR_PACK(0,EC_F_EC_GF2M_SIMPLE_POINT_GET_AFFINE_COORDINATES,0),	"ec_GF2m_simple_point_get_affine_coordinates"},
@@ -116,6 +117,8 @@ static ERR_STRING_DATA EC_str_functs[]=
 {ERR_PACK(0,EC_F_EC_GROUP_GET_DEGREE,0),	"EC_GROUP_get_degree"},
 {ERR_PACK(0,EC_F_EC_GROUP_GET_EXTRA_DATA,0),	"EC_GROUP_get_extra_data"},
 {ERR_PACK(0,EC_F_EC_GROUP_GET_ORDER,0),	"EC_GROUP_get_order"},
+{ERR_PACK(0,EC_F_EC_GROUP_GET_PENTANOMIAL_BASIS,0),	"EC_GROUP_get_pentanomial_basis"},
+{ERR_PACK(0,EC_F_EC_GROUP_GET_TRINOMIAL_BASIS,0),	"EC_GROUP_get_trinomial_basis"},
 {ERR_PACK(0,EC_F_EC_GROUP_GROUP2NID,0),	"EC_GROUP_GROUP2NID"},
 {ERR_PACK(0,EC_F_EC_GROUP_NEW,0),	"EC_GROUP_new"},
 {ERR_PACK(0,EC_F_EC_GROUP_NEW_BY_NID,0),	"EC_GROUP_new_by_nid"},
@@ -195,6 +198,7 @@ static ERR_STRING_DATA EC_str_reasons[]=
 {EC_R_UNDEFINED_ORDER                    ,"undefined order"},
 {EC_R_UNKNOWN_GROUP                      ,"unknown group"},
 {EC_R_UNKNOWN_ORDER                      ,"unknown order"},
+{EC_R_UNSUPPORTED_FIELD                  ,"unsupported field"},
 {EC_R_WRONG_ORDER                        ,"wrong order"},
 {0,NULL}
 	};