From 30daf914cee4594c1482da861bfdcf7d7d16cfc5 Mon Sep 17 00:00:00 2001
From: iceman1001 <iceman@iuse.se>
Date: Fri, 28 Oct 2016 13:06:34 +0200
Subject: [PATCH] FIX: looping logic error, doesn't need to increase with 1,
if we do 8 checks every turn...
---
armsrc/iso14443a.c | 25 ++++++++++---------------
1 file changed, 10 insertions(+), 15 deletions(-)
diff --git a/armsrc/iso14443a.c b/armsrc/iso14443a.c
index 570f028c..4bd55fb3 100644
--- a/armsrc/iso14443a.c
+++ b/armsrc/iso14443a.c
@@ -2145,29 +2145,24 @@ int32_t dist_nt(uint32_t nt1, uint32_t nt2) {
uint32_t nttmp1 = nt1;
uint32_t nttmp2 = nt2;
- for (uint16_t i = 1; i < 32768/8; ++i) {
+ // 0xFFFF -- Half up and half down to find distance between nonces
+ for (uint16_t i = 1; i < 32768/8; i += 8) {
nttmp1 = prng_successor(nttmp1, 1); if (nttmp1 == nt2) return i;
- nttmp2 = prng_successor(nttmp2, 1); if (nttmp2 == nt1) return -i;
-
nttmp1 = prng_successor(nttmp1, 1); if (nttmp1 == nt2) return i+1;
- nttmp2 = prng_successor(nttmp2, 1); if (nttmp2 == nt1) return -(i+1);
-
nttmp1 = prng_successor(nttmp1, 1); if (nttmp1 == nt2) return i+2;
- nttmp2 = prng_successor(nttmp2, 1); if (nttmp2 == nt1) return -(i+2);
-
nttmp1 = prng_successor(nttmp1, 1); if (nttmp1 == nt2) return i+3;
- nttmp2 = prng_successor(nttmp2, 1); if (nttmp2 == nt1) return -(i+3);
-
nttmp1 = prng_successor(nttmp1, 1); if (nttmp1 == nt2) return i+4;
- nttmp2 = prng_successor(nttmp2, 1); if (nttmp2 == nt1) return -(i+4);
-
nttmp1 = prng_successor(nttmp1, 1); if (nttmp1 == nt2) return i+5;
- nttmp2 = prng_successor(nttmp2, 1); if (nttmp2 == nt1) return -(i+5);
-
nttmp1 = prng_successor(nttmp1, 1); if (nttmp1 == nt2) return i+6;
- nttmp2 = prng_successor(nttmp2, 1); if (nttmp2 == nt1) return -(i+6);
-
nttmp1 = prng_successor(nttmp1, 1); if (nttmp1 == nt2) return i+7;
+
+ nttmp2 = prng_successor(nttmp2, 1); if (nttmp2 == nt1) return -i;
+ nttmp2 = prng_successor(nttmp2, 1); if (nttmp2 == nt1) return -(i+1);
+ nttmp2 = prng_successor(nttmp2, 1); if (nttmp2 == nt1) return -(i+2);
+ nttmp2 = prng_successor(nttmp2, 1); if (nttmp2 == nt1) return -(i+3);
+ nttmp2 = prng_successor(nttmp2, 1); if (nttmp2 == nt1) return -(i+4);
+ nttmp2 = prng_successor(nttmp2, 1); if (nttmp2 == nt1) return -(i+5);
+ nttmp2 = prng_successor(nttmp2, 1); if (nttmp2 == nt1) return -(i+6);
nttmp2 = prng_successor(nttmp2, 1); if (nttmp2 == nt1) return -(i+7);
}
// either nt1 or nt2 are invalid nonces
--
2.39.5