bn_mod_sqrt: Improve a handful of comments and a printf

diff --git a/regress/lib/libcrypto/bn/bn_mod_sqrt.c b/regress/lib/libcrypto/bn/bn_mod_sqrt.c
index 4333829..5273aba 100644 (file)
--- a/regress/lib/libcrypto/bn/bn_mod_sqrt.c
+++ b/regress/lib/libcrypto/bn/bn_mod_sqrt.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: bn_mod_sqrt.c,v 1.7 2023/04/05 10:47:00 tb Exp $ */
+/*     $OpenBSD: bn_mod_sqrt.c,v 1.8 2023/04/05 11:03:11 tb Exp $ */
 
 /*
  * Copyright (c) 2022,2023 Theo Buehler <tb@openbsd.org>
@@ -21,7 +21,11 @@
 
 #include <openssl/bn.h>
 
-/* Test that sqrt * sqrt = A (mod p) where p is a prime */
+/*
+ * Test that .sqrt * .sqrt = .a (mod .p) where .p is a prime.  If .sqrt is
+ * omitted, .a does not have a square root and BN_mod_sqrt() fails.
+ */
+
 struct mod_sqrt_test {
        const char *a;
        const char *p;
@@ -1455,7 +1459,7 @@ struct mod_sqrt_test {
        },
 
        /*
-        * p = 1 (mod 8), short initial segment of residues
+        * p = 1 (mod 8), short initial segment of quadratic residues
         */
 
        {
@@ -2140,7 +2144,7 @@ struct mod_sqrt_test {
        },
 
        /*
-        * p = 1 (mod 8), long initial segment of residues
+        * p = 1 (mod 8), long initial segment of quadratic residues
         */
 
        {
@@ -2872,7 +2876,7 @@ mod_sqrt_test(struct mod_sqrt_test *test, BN_CTX *ctx)
        if (!BN_is_zero(diff) && !BN_is_zero(sum)) {
                fprintf(stderr, "a: %s\n", test->a);
                fprintf(stderr, "p: %s\n", test->p);
-               fprintf(stderr, "want: %s:", test->sqrt);
+               fprintf(stderr, "want: %s\n", test->sqrt);
                fprintf(stderr, "got: ");
                BN_print_fp(stderr, got);
                fprintf(stderr, "\n\n");