ec_asn1_test: clean up & refactor; test Wei25519 with simple method

1 files changed, 189 insertions, 109 deletions

diff --git a/regress/lib/libcrypto/ec/ec_asn1_test.c b/regress/lib/libcrypto/ec/ec_asn1_test.c
index 171014bda7e..c53864cadd4 100644
--- a/regress/lib/libcrypto/ec/ec_asn1_test.c
+++ b/regress/lib/libcrypto/ec/ec_asn1_test.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ec_asn1_test.c,v 1.6 2024/10/16 23:58:25 tb Exp $ */
+/* $OpenBSD: ec_asn1_test.c,v 1.7 2024/10/18 09:01:44 tb Exp $ */
 /*
  * Copyright (c) 2017, 2021 Joel Sing <jsing@openbsd.org>
  * Copyright (c) 2024 Theo Buehler <tb@openbsd.org>
@@ -344,35 +344,6 @@ ec_group_roundtrip_builtin_curves(void)
  * From draft-ietf-lwig-curve-representation-23, Appendix E.3
  */
 
-static const struct {
-	const char *oid;
-	const char *sn;
-	const char *ln;
-	const char *p;
-	const char *a;
-	const char *b;
-	const char *order;
-	const char *cofactor;
-	const char *x;
-	const char *y;
-} wei25519 = {
-	.oid = "1.3.101.108",
-	.sn = "Wei25519",
-	.p =	 "7fffffff" "ffffffff" "ffffffff" "ffffffff"
-		 "ffffffff" "ffffffff" "ffffffff" "ffffffed",
-	.a =	 "2aaaaaaa" "aaaaaaaa" "aaaaaaaa" "aaaaaaaa"
-		 "aaaaaaaa" "aaaaaaaa" "aaaaaa98" "4914a144",
-	.b =	 "7b425ed0" "97b425ed" "097b425e" "d097b425"
-		 "ed097b42" "5ed097b4" "260b5e9c" "7710c864",
-	.x =	 "2aaaaaaa" "aaaaaaaa" "aaaaaaaa" "aaaaaaaa"
-		 "aaaaaaaa" "aaaaaaaa" "aaaaaaaa" "aaad245a",
-	.y =	 "20ae19a1" "b8a086b4" "e01edd2c" "7748d14c"
-		 "923d4d7e" "6d7c61b2" "29e9c5a2" "7eced3d9",
-	.order = "10000000" "00000000" "00000000" "00000000"
-		 "14def9de" "a2f79cd6" "5812631a" "5cf5d3ed",
-	.cofactor = "8",
-};
-
 const uint8_t ec_wei25519_pkparameters_named_curve[] = {
 	0x06, 0x03, 0x2b, 0x65, 0x6c,
 };
@@ -409,100 +380,163 @@ const uint8_t ec_wei25519_pkparameters_parameters[] = {
 	0x08,
 };
 
-static int
-ec_weierstrass25519(void)
+struct curve {
+	const char *oid;
+	const char *sn;
+	const char *ln;
+	const char *p;
+	const char *a;
+	const char *b;
+	const char *order;
+	const char *cofactor;
+	const char *x;
+	const char *y;
+	const char *named;
+	size_t named_len;
+	const char *param;
+	size_t param_len;
+};
+
+static const struct curve wei25519 = {
+	.oid = "1.3.101.108",
+	.sn = "Wei25519",
+	.p =	 "7fffffff" "ffffffff" "ffffffff" "ffffffff"
+		 "ffffffff" "ffffffff" "ffffffff" "ffffffed",
+	.a =	 "2aaaaaaa" "aaaaaaaa" "aaaaaaaa" "aaaaaaaa"
+		 "aaaaaaaa" "aaaaaaaa" "aaaaaa98" "4914a144",
+	.b =	 "7b425ed0" "97b425ed" "097b425e" "d097b425"
+		 "ed097b42" "5ed097b4" "260b5e9c" "7710c864",
+	.x =	 "2aaaaaaa" "aaaaaaaa" "aaaaaaaa" "aaaaaaaa"
+		 "aaaaaaaa" "aaaaaaaa" "aaaaaaaa" "aaad245a",
+	.y =	 "20ae19a1" "b8a086b4" "e01edd2c" "7748d14c"
+		 "923d4d7e" "6d7c61b2" "29e9c5a2" "7eced3d9",
+	.order = "10000000" "00000000" "00000000" "00000000"
+		 "14def9de" "a2f79cd6" "5812631a" "5cf5d3ed",
+	.cofactor = "8",
+	.named = ec_wei25519_pkparameters_named_curve,
+	.named_len = sizeof(ec_wei25519_pkparameters_named_curve),
+	.param = ec_wei25519_pkparameters_parameters,
+	.param_len = sizeof(ec_wei25519_pkparameters_parameters),
+};
+
+static EC_GROUP *
+ec_group_from_curve_method(const struct curve *curve, const EC_METHOD *method,
+    BN_CTX *ctx)
 {
-	EC_GROUP *group = NULL, *new_group = NULL;
+	EC_GROUP *group;
 	EC_POINT *generator = NULL;
-	BN_CTX *ctx = NULL;
 	BIGNUM *p, *a, *b;
-	BIGNUM *order, *cofactor, *guessed_cofactor, *x, *y;
-	const unsigned char *pder;
-	unsigned char *der = NULL;
-	long error;
-	int der_len = 0;
-	int nid;
-	int failed = 1;
+	BIGNUM *order, *x, *y;
 
-	ERR_clear_error();
-	if ((ctx = BN_CTX_new()) == NULL)
-		goto err;
 	BN_CTX_start(ctx);
 
-	if ((nid = OBJ_create(wei25519.oid, wei25519.sn, NULL)) == NID_undef) {
-		fprintf(stderr, "FAIL: %s OBJ_create(wei25519)\n", __func__);
-		goto err;
-	}
-
 	if ((p = BN_CTX_get(ctx)) == NULL)
 		errx(1, "BN_CTX_get");
 	if ((a = BN_CTX_get(ctx)) == NULL)
 		errx(1, "BN_CTX_get");
 	if ((b = BN_CTX_get(ctx)) == NULL)
 		errx(1, "BN_CTX_get");
+
 	if ((order = BN_CTX_get(ctx)) == NULL)
 		errx(1, "BN_CTX_get");
-	if ((cofactor = BN_CTX_get(ctx)) == NULL)
-		errx(1, "BN_CTX_get");
-	if ((guessed_cofactor = BN_CTX_get(ctx)) == NULL)
-		errx(1, "BN_CTX_get");
 	if ((x = BN_CTX_get(ctx)) == NULL)
 		errx(1, "BN_CTX_get");
 	if ((y = BN_CTX_get(ctx)) == NULL)
 		errx(1, "BN_CTX_get");
 
-	if (BN_hex2bn(&p, wei25519.p) == 0)
+	if (BN_hex2bn(&p, curve->p) == 0)
 		errx(1, "BN_hex2bn(p)");
-	if (BN_hex2bn(&a, wei25519.a) == 0)
+	if (BN_hex2bn(&a, curve->a) == 0)
 		errx(1, "BN_hex2bn(a)");
-	if (BN_hex2bn(&b, wei25519.b) == 0)
+	if (BN_hex2bn(&b, curve->b) == 0)
 		errx(1, "BN_hex2bn(b)");
 
-	/*
-	 * XXX - this uses the Montgomery method. Consider exercising the
-	 * simple method as well.
-	 */
-	if ((group = EC_GROUP_new_curve_GFp(p, a, b, ctx)) == NULL) {
-		fprintf(stderr, "FAIL: %s EC_GROUP_new_curve_GFp", __func__);
-		goto err;
-	}
+	if ((group = EC_GROUP_new(method)) == NULL)
+		errx(1, "EC_GROUP_new");
+
+	if (!EC_GROUP_set_curve(group, p, a, b, ctx))
+		errx(1, "EC_GROUP_set_curve");
 
-	if (BN_hex2bn(&x, wei25519.x) == 0)
+	if (BN_hex2bn(&x, curve->x) == 0)
 		errx(1, "BN_hex2bn(x)");
-	if (BN_hex2bn(&x, wei25519.x) == 0)
+	if (BN_hex2bn(&x, curve->x) == 0)
 		errx(1, "BN_hex2bn(x)");
-	if (BN_hex2bn(&y, wei25519.y) == 0)
+	if (BN_hex2bn(&y, curve->y) == 0)
 		errx(1, "BN_hex2bn(y)");
 
 	if ((generator = EC_POINT_new(group)) == NULL)
 		errx(1, "EC_POINT_new()");
 
 	if (!EC_POINT_set_affine_coordinates(group, generator, x, y, ctx)) {
-		fprintf(stderr, "FAIL: %s EC_POINT_set_affine_coordinates", __func__);
+		fprintf(stderr, "FAIL: %s EC_POINT_set_affine_coordinates",
+		    curve->sn);
 		ERR_print_errors_fp(stderr);
 		goto err;
 	}
 
-	if (BN_hex2bn(&order, wei25519.order) == 0)
+	if (BN_hex2bn(&order, curve->order) == 0)
 		errx(1, "BN_hex2bn(order)");
-	if (BN_hex2bn(&cofactor, wei25519.cofactor) == 0)
-		errx(1, "BN_hex2bn(cofactor)");
 
 	/* Don't set cofactor to exercise the cofactor guessing code. */
 	if (!EC_GROUP_set_generator(group, generator, order, NULL)) {
-		fprintf(stderr, "FAIL: %s EC_GROUP_set_generator\n", __func__);
+		fprintf(stderr, "FAIL: %s EC_GROUP_set_generator\n", curve->sn);
+		ERR_print_errors_fp(stderr);
+		goto err;
+	}
+
+	EC_POINT_free(generator);
+
+	BN_CTX_end(ctx);
+
+	return group;
+
+ err:
+	BN_CTX_end(ctx);
+
+	EC_POINT_free(generator);
+	EC_GROUP_free(group);
+
+	return NULL;
+}
+
+static EC_GROUP *
+ec_group_new(const struct curve *curve, const EC_METHOD *method, BN_CTX *ctx)
+{
+	EC_GROUP *group = NULL;
+	BIGNUM *cofactor, *guessed_cofactor;
+	int nid;
+
+	BN_CTX_start(ctx);
+
+	if ((nid = OBJ_txt2nid(curve->oid)) == NID_undef)
+		nid = OBJ_create(curve->oid, curve->sn, curve->ln);
+	if (nid == NID_undef) {
+		fprintf(stderr, "FAIL: OBJ_create(%s)\n", curve->sn);
+		goto err;
+	}
+
+	if ((cofactor = BN_CTX_get(ctx)) == NULL)
+		errx(1, "BN_CTX_get");
+	if ((guessed_cofactor = BN_CTX_get(ctx)) == NULL)
+		errx(1, "BN_CTX_get");
+
+	if (BN_hex2bn(&cofactor, curve->cofactor) == 0)
+		errx(1, "BN_hex2bn(cofactor)");
+
+	if ((group = ec_group_from_curve_method(curve, method, ctx)) == NULL) {
+		fprintf(stderr, "FAIL: %s ec_group_from_curve_method\n", curve->sn);
 		ERR_print_errors_fp(stderr);
 		goto err;
 	}
 
 	if (!EC_GROUP_get_cofactor(group, guessed_cofactor, ctx)) {
-		fprintf(stderr, "FAIL: %s EC_GROUP_get_cofactor\n", __func__);
+		fprintf(stderr, "FAIL: %s EC_GROUP_get_cofactor\n", curve->sn);
 		ERR_print_errors_fp(stderr);
 		goto err;
 	}
 
 	if (BN_cmp(cofactor, guessed_cofactor) != 0) {
-		fprintf(stderr, "FAIL: %s cofactor: want ", __func__);
+		fprintf(stderr, "FAIL: %s cofactor: want ", curve->sn);
 		BN_print_fp(stderr, cofactor);
 		fprintf(stderr, ", got ");
 		BN_print_fp(stderr, guessed_cofactor);
@@ -511,49 +545,80 @@ ec_weierstrass25519(void)
 	}
 
 	if (!EC_GROUP_check(group, ctx)) {
-		fprintf(stderr, "FAIL: %s EC_GROUP_check\n", __func__);
+		fprintf(stderr, "FAIL: %s EC_GROUP_check\n", curve->sn);
 		ERR_print_errors_fp(stderr);
 		goto err;
 	}
 
-	/* Explicit curve parameter encoding should work without NID set. */
-	if (EC_GROUP_get_curve_name(group) != NID_undef) {
-		fprintf(stderr, "FAIL: %s unexpected curve name %d\n", __func__,
-		    EC_GROUP_get_curve_name(group));
-		ERR_print_errors_fp(stderr);
+	EC_GROUP_set_curve_name(group, nid);
+
+	BN_CTX_end(ctx);
+
+	return group;
+
+ err:
+	BN_CTX_end(ctx);
+
+	EC_GROUP_free(group);
+
+	return NULL;
+}
+
+static int
+ec_group_non_builtin_curve(const struct curve *curve, const EC_METHOD *method,
+    BN_CTX *ctx)
+{
+	EC_GROUP *group = NULL, *new_group = NULL;
+	const unsigned char *pder;
+	unsigned char *der = NULL;
+	long error;
+	int der_len = 0;
+	int nid;
+	int failed = 1;
+
+	ERR_clear_error();
+	BN_CTX_start(ctx);
+
+	if ((group = ec_group_new(curve, method, ctx)) == NULL)
+		goto err;
+
+	if ((nid = EC_GROUP_get_curve_name(group)) == NID_undef) {
+		fprintf(stderr, "FAIL: no curve name set for %s\n", curve->sn);
 		goto err;
 	}
 
-	EC_GROUP_set_asn1_flag(group, OPENSSL_EC_EXPLICIT_CURVE);
+	EC_GROUP_set_asn1_flag(group, OPENSSL_EC_NAMED_CURVE);
 
 	der = NULL;
 	if ((der_len = i2d_ECPKParameters(group, &der)) <= 0) {
-		fprintf(stderr, "FAIL: %s i2d_ECPKParameters (explicit)\n", __func__);
+		fprintf(stderr, "FAIL: %s i2d_ECPKParameters (named)\n",
+		    curve->sn);
 		ERR_print_errors_fp(stderr);
 		goto err;
 	}
 
-	if (compare_data("Weierstrass 25519 explicit", der, der_len,
-	    ec_wei25519_pkparameters_parameters,
-	    sizeof(ec_wei25519_pkparameters_parameters)) == -1)
+	if (compare_data("Weierstrass 25519 named curve", der, der_len,
+	    ec_wei25519_pkparameters_named_curve,
+	    sizeof(ec_wei25519_pkparameters_named_curve)) == -1)
 		goto err;
 
 	freezero(der, der_len);
 	der = NULL;
 
-	EC_GROUP_set_curve_name(group, nid);
-	EC_GROUP_set_asn1_flag(group, OPENSSL_EC_NAMED_CURVE);
+	/* Explicit curve parameter encoding should work without NID set. */
+	EC_GROUP_set_curve_name(group, NID_undef);
+	EC_GROUP_set_asn1_flag(group, OPENSSL_EC_EXPLICIT_CURVE);
 
 	der = NULL;
 	if ((der_len = i2d_ECPKParameters(group, &der)) <= 0) {
-		fprintf(stderr, "FAIL: %s i2d_ECPKParameters (named)\n", __func__);
+		fprintf(stderr, "FAIL: i2d_ECPKParameters (explicit) %s\n",
+		    curve->sn);
 		ERR_print_errors_fp(stderr);
 		goto err;
 	}
 
-	if (compare_data("Weierstrass 25519 named curve", der, der_len,
-	    ec_wei25519_pkparameters_named_curve,
-	    sizeof(ec_wei25519_pkparameters_named_curve)) == -1)
+	if (compare_data(curve->sn, der, der_len,
+	    curve->param, curve->param_len) == -1)
 		goto err;
 
 	freezero(der, der_len);
@@ -561,51 +626,51 @@ ec_weierstrass25519(void)
 
 	/* At this point we should have no error on the stack. */
 	if (ERR_peek_last_error() != 0) {
-		fprintf(stderr, "FAIL: %s unexpected error %lu\n", __func__,
+		fprintf(stderr, "FAIL: %s unexpected error %lu\n", curve->sn,
 		    ERR_peek_last_error());
 		goto err;
 	}
 
-	pder = ec_wei25519_pkparameters_named_curve;
-	der_len = sizeof(ec_wei25519_pkparameters_named_curve);
+	pder = curve->named;
+	der_len = curve->named_len;
 	if ((new_group = d2i_ECPKParameters(NULL, &pder, der_len)) != NULL) {
-		fprintf(stderr, "FAIL: %s managed to decode unknown named curve\n",
-		    __func__);
+		fprintf(stderr, "FAIL: managed to decode unknown named curve %s\n",
+		    curve->sn);
 		goto err;
 	}
 
 	error = ERR_get_error();
 	if (ERR_GET_REASON(error) != EC_R_UNKNOWN_GROUP) {
 		fprintf(stderr, "FAIL: %s unexpected error: want %d, got %d\n",
-		    __func__, EC_R_UNKNOWN_GROUP, ERR_GET_REASON(error));
+		    curve->sn, EC_R_UNKNOWN_GROUP, ERR_GET_REASON(error));
 		goto err;
 	}
 
 	ERR_clear_error();
-	pder = ec_wei25519_pkparameters_parameters;
-	der_len = sizeof(ec_wei25519_pkparameters_parameters);
-
+	pder = curve->param;
+	der_len = curve->param_len;
 #if 0
 	if ((new_group = d2i_ECPKParameters(NULL, &pder, der_len)) != NULL) {
-		fprintf(stderr, "FAIL: %s managed to decode non-builtin parameters\n",
-		    __func__);
+		fprintf(stderr, "FAIL: managed to decode non-builtin parameters %s\n",
+		    curve->sn);
 		goto err;
 	}
 
 	error = ERR_peek_last_error();
 	if (ERR_GET_REASON(error) != EC_R_PKPARAMETERS2GROUP_FAILURE) {
 		fprintf(stderr, "FAIL: %s unexpected error: want %d, got %d\n",
-		    __func__, EC_R_UNKNOWN_GROUP, ERR_GET_REASON(error));
+		    curve->sn, EC_R_UNKNOWN_GROUP, ERR_GET_REASON(error));
 		goto err;
 	}
 #else
 	if ((new_group = d2i_ECPKParameters(NULL, &pder, der_len)) == NULL) {
-		fprintf(stderr, "FAIL: %s d2i_ECPKParameters(Wei25519)\n", __func__);
+		fprintf(stderr, "FAIL: d2i_ECPKParameters(%s)\n", curve->sn);
 		goto err;
 	}
-	if (EC_GROUP_cmp(group, new_group, ctx) != 0) {
+	if (method == EC_GFp_mont_method() &&
+	    EC_GROUP_cmp(group, new_group, ctx) != 0) {
 		fprintf(stderr, "FAIL: %s Weierstrass groups do not match!\n",
-		    __func__);
+		    curve->sn);
 		goto err;
 	}
 #endif
@@ -614,17 +679,32 @@ ec_weierstrass25519(void)
 
  err:
 	BN_CTX_end(ctx);
-	BN_CTX_free(ctx);
 
 	EC_GROUP_free(group);
 	EC_GROUP_free(new_group);
-	EC_POINT_free(generator);
 
 	freezero(der, der_len);
 
 	return failed;
 }
 
+static int
+ec_group_non_builtin_curves(void)
+{
+	BN_CTX *ctx;
+	int failed = 0;
+
+	if ((ctx = BN_CTX_new()) == NULL)
+		errx(1, "BN_CTX_new");
+
+	failed |= ec_group_non_builtin_curve(&wei25519, EC_GFp_mont_method(), ctx);
+	failed |= ec_group_non_builtin_curve(&wei25519, EC_GFp_simple_method(), ctx);
+
+	BN_CTX_free(ctx);
+
+	return failed;
+}
+
 int
 main(int argc, char **argv)
 {
@@ -634,7 +714,7 @@ main(int argc, char **argv)
 	failed |= ec_group_pkparameters_parameters_test();
 	failed |= ec_group_pkparameters_correct_padding_test();
 	failed |= ec_group_roundtrip_builtin_curves();
-	failed |= ec_weierstrass25519();
+	failed |= ec_group_non_builtin_curves();
 
 	return (failed);
 }