From 5550240d8c41762963406e1f987743bdc4644a45 Mon Sep 17 00:00:00 2001
From: tb <tb@openbsd.org>
Date: Fri, 7 Apr 2023 22:28:21 +0000
Subject: [PATCH] bn_test: keep the error stack clean

Make message() print and clear the error stack. This way we can know
what test errored. To make this work also clear the error stack after
a handful of xfail tests.
---
 regress/lib/libcrypto/bn/bn_test.c | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/regress/lib/libcrypto/bn/bn_test.c b/regress/lib/libcrypto/bn/bn_test.c
index a5fe58f55a4..1476a92ee2d 100644
--- a/regress/lib/libcrypto/bn/bn_test.c
+++ b/regress/lib/libcrypto/bn/bn_test.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: bn_test.c,v 1.8 2023/04/07 22:25:09 tb Exp $	*/
+/*	$OpenBSD: bn_test.c,v 1.9 2023/04/07 22:28:21 tb Exp $	*/
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -135,6 +135,9 @@ static int results = 0;
 static void
 message(BIO *out, char *m)
 {
+	ERR_print_errors_fp(stderr);
+	ERR_clear_error();
+
 	fprintf(stderr, "test %s\n", m);
 	BIO_puts(out, "print \"test ");
 	BIO_puts(out, m);
@@ -483,6 +486,7 @@ test_div(BIO *bp, BN_CTX *ctx)
 		fprintf(stderr, "Division by zero succeeded!\n");
 		goto err;
 	}
+	ERR_clear_error();
 
 	for (i = 0; i < num0 + num1; i++) {
 		if (i < num1) {
@@ -895,12 +899,14 @@ test_mont(BIO *bp, BN_CTX *ctx)
 		fprintf(stderr, "BN_MONT_CTX_set succeeded for zero modulus!\n");
 		goto err;
 	}
+	ERR_clear_error();
 
 	CHECK_GOTO(BN_set_word(n, 16));
 	if (BN_MONT_CTX_set(mont, n, ctx)) {
 		fprintf(stderr, "BN_MONT_CTX_set succeeded for even modulus!\n");
 		goto err;
 	}
+	ERR_clear_error();
 
 	CHECK_GOTO(BN_bntest_rand(a, 100, 0, 0));
 	CHECK_GOTO(BN_bntest_rand(b, 100, 0, 0));
@@ -1033,6 +1039,7 @@ test_mod_mul(BIO *bp, BN_CTX *ctx)
 		fprintf(stderr, "BN_mod_mul with zero modulus succeeded!\n");
 		goto err;
 	}
+	ERR_clear_error();
 
 	for (j = 0; j < 3; j++) {
 		CHECK_GOTO(BN_bntest_rand(c, 1024, 0, 0));
@@ -1118,14 +1125,17 @@ test_mod_exp(BIO *bp, BN_CTX *ctx)
 		fprintf(stderr, "BN_mod_exp with zero modulus succeeded!\n");
 		goto err;
 	}
+	ERR_clear_error();
 	if (BN_mod_exp_ct(d, a, b, c, ctx)) {
 		fprintf(stderr, "BN_mod_exp_ct with zero modulus succeeded!\n");
 		goto err;
 	}
+	ERR_clear_error();
 	if (BN_mod_exp_nonct(d, a, b, c, ctx)) {
 		fprintf(stderr, "BN_mod_exp_nonct with zero modulus succeeded!\n");
 		goto err;
 	}
+	ERR_clear_error();
 
 	CHECK_GOTO(BN_bntest_rand(c, 30, 0, 1)); /* must be odd for montgomery */
 	for (i = 0; i < num2; i++) {
@@ -1254,6 +1264,7 @@ test_mod_exp_mont_consttime(BIO *bp, BN_CTX *ctx)
 				"succeeded\n");
 		goto err;
 	}
+	ERR_clear_error();
 
 	CHECK_GOTO(BN_set_word(c, 16));
 	if (BN_mod_exp_mont_consttime(d, a, b, c, ctx, NULL)) {
@@ -1261,6 +1272,7 @@ test_mod_exp_mont_consttime(BIO *bp, BN_CTX *ctx)
 				"succeeded\n");
 		goto err;
 	}
+	ERR_clear_error();
 
 	CHECK_GOTO(BN_bntest_rand(c, 30, 0, 1)); /* must be odd for montgomery */
 	for (i = 0; i < num2; i++) {
-- 
2.20.1