rsa.c: Fix incorrect commentary.

[secnet.git] / rsa.c

diff --git a/rsa.c b/rsa.c
index 0bd106ff3526935734641b239cdb3ec91649de2b..fed468dc3ef46f67d9d54dbfa608805cbc8962e4 100644 (file)
--- a/rsa.c
+++ b/rsa.c
@@ -430,8 +430,9 @@ static list_t *rsapriv_apply(closure_t *self, struct cloc loc, dict_t *context,
        /*
         * Verify that d*e is congruent to 1 mod (p-1), and mod
         * (q-1). This is equivalent to it being congruent to 1 mod
-        * lcm(p-1,q-1), i.e. congruent to 1 mod phi(n). Note that
-        * phi(n) is _not_ simply (p-1)*(q-1).
+        * lambda(n) = lcm(p-1,q-1).  The usual `textbook' condition,
+        * that d e == 1 (mod (p-1)(q-1)) is sufficient, but not
+        * actually necessary.
         */
        mpz_mul(&tmp, &d, &e);
        mpz_sub_ui(&tmp2, &st->p, 1);