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.

diff --git a/regress/lib/libcrypto/bn/bn_test.c b/regress/lib/libcrypto/bn/bn_test.c
index a5fe58f..1476a92 100644 (file)
--- 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++) {