From 8fc1af1b7eea89e942c4af4ebcc7b8d8abfc8eff Mon Sep 17 00:00:00 2001
From: Steffen Jaeckel <s@jaeckel.eu>
Date: Wed, 15 Feb 2017 23:15:43 +0100
Subject: [PATCH] make implementation easier to read
damn you negated logic...
---
src/pk/rsa/rsa_exptmod.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)
diff --git a/src/pk/rsa/rsa_exptmod.c b/src/pk/rsa/rsa_exptmod.c
index 78858fe..714bc52 100644
--- a/src/pk/rsa/rsa_exptmod.c
+++ b/src/pk/rsa/rsa_exptmod.c
@@ -38,7 +38,7 @@ int rsa_exptmod(const unsigned char *in, unsigned long inlen,
void *rnd, *rndi /* inverse of rnd */;
#endif
unsigned long x;
- int err, no_crt;
+ int err, has_crt_parameters;
LTC_ARGCHK(in != NULL);
LTC_ARGCHK(out != NULL);
@@ -100,9 +100,11 @@ int rsa_exptmod(const unsigned char *in, unsigned long inlen,
}
#endif /* LTC_RSA_BLINDING */
- no_crt = (key->dP == NULL) || (mp_get_digit_count(key->dP) == 0);
+ has_crt_parameters = (key->dP != NULL) && (mp_get_digit_count(key->dP) != 0) &&
+ (key->dQ != NULL) && (mp_get_digit_count(key->dQ) != 0) &&
+ (key->qP != NULL) && (mp_get_digit_count(key->qP) != 0);
- if (no_crt) {
+ if (!has_crt_parameters) {
/*
* In case CRT optimization parameters are not provided,
* the private key is directly used to exptmod it
@@ -133,7 +135,7 @@ int rsa_exptmod(const unsigned char *in, unsigned long inlen,
#endif
#ifdef LTC_RSA_CRT_HARDENING
- if (!no_crt) {
+ if (has_crt_parameters) {
if ((err = mp_exptmod(tmp, key->e, key->N, tmpa)) != CRYPT_OK) { goto error; }
if ((err = mp_read_unsigned_bin(tmpb, (unsigned char *)in, (int)inlen)) != CRYPT_OK) { goto error; }
if (mp_cmp(tmpa, tmpb) != LTC_MP_EQ) { err = CRYPT_ERROR; goto error; }