Expand the comment explaining the for loop with bn_lucas_step() a bit.

diff --git a/lib/libcrypto/bn/bn_bpsw.c b/lib/libcrypto/bn/bn_bpsw.c
index f189571..ca63410 100644 (file)
--- a/lib/libcrypto/bn/bn_bpsw.c
+++ b/lib/libcrypto/bn/bn_bpsw.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: bn_bpsw.c,v 1.2 2022/07/15 06:14:17 tb Exp $ */
+/*     $OpenBSD: bn_bpsw.c,v 1.3 2022/07/15 06:19:27 tb Exp $ */
 /*
  * Copyright (c) 2022 Martin Grenouilloux <martin.grenouilloux@lse.epita.fr>
  * Copyright (c) 2022 Theo Buehler <tb@openbsd.org>
@@ -192,8 +192,8 @@ bn_strong_lucas_test(int *is_prime, const BIGNUM *n, const BIGNUM *D,
        }
 
        /*
-        * If any V_{k * 2^r} is zero for 1 <= r < s then n is a strong Lucas
-        * pseudoprime.
+        * Calculate the Lucas terms U_{k * 2^r}, V_{k * 2^r} for 1 <= r < s.
+        * If any V_{k * 2^r} is zero then n is a strong Lucas pseudoprime.
         */
        for (r = 1; r < s; r++) {
                if (!bn_lucas_step(U, V, 0, D, n, ctx))