From a1ab594e244c1554b2e997efa8813e8ec3b80017 Mon Sep 17 00:00:00 2001 From: iceman1001 Date: Wed, 24 Aug 2016 12:35:24 +0200 Subject: [PATCH] CHG: change the number of calls to prng_successor was done. Fewer should mean faster :) --- common/usb_cdc.c | 4 ++-- tools/mfkey/mfkey32.c | 13 +++++++------ tools/mfkey/mfkey32v2.c | 14 +++++++++----- 3 files changed, 18 insertions(+), 13 deletions(-) diff --git a/common/usb_cdc.c b/common/usb_cdc.c index 9bdaed29..4d7ea3ed 100644 --- a/common/usb_cdc.c +++ b/common/usb_cdc.c @@ -291,8 +291,8 @@ bool usb_check() { bool usb_poll() { - if (!usb_check()) return false; - return (pUdp->UDP_CSR[AT91C_EP_OUT] & btReceiveBank); + if (!usb_check()) return false; + return (pUdp->UDP_CSR[AT91C_EP_OUT] & btReceiveBank); } /** diff --git a/tools/mfkey/mfkey32.c b/tools/mfkey/mfkey32.c index c122b77b..43e5a094 100755 --- a/tools/mfkey/mfkey32.c +++ b/tools/mfkey/mfkey32.c @@ -43,17 +43,18 @@ int main (int argc, char *argv[]) { // Generate lfsr succesors of the tag challenge printf("\nLFSR succesors of the tag challenge:\n"); - printf(" nt': %08x\n",prng_successor(nt, 64)); - printf(" nt'': %08x\n",prng_successor(nt, 96)); + uint32_t p64 = prng_successor(nt, 64); + printf(" nt': %08x\n", p64); + printf(" nt'': %08x\n", prng_successor(p64, 32)); clock_t t1 = clock(); // Extract the keystream from the messages printf("\nKeystream used to generate {ar} and {at}:\n"); - ks2 = ar0_enc ^ prng_successor(nt, 64); - printf(" ks2: %08x\n",ks2); + ks2 = ar0_enc ^ p64; + printf(" ks2: %08x\n", ks2); - s = lfsr_recovery32(ar0_enc ^ prng_successor(nt, 64), 0); + s = lfsr_recovery32(ar0_enc ^ p64, 0); for(t = s; t->odd | t->even; ++t) { lfsr_rollback_word(t, 0, 0); @@ -62,7 +63,7 @@ int main (int argc, char *argv[]) { crypto1_get_lfsr(t, &key); crypto1_word(t, uid ^ nt, 0); crypto1_word(t, nr1_enc, 1); - if (ar1_enc == (crypto1_word(t, 0, 0) ^ prng_successor(nt, 64))) { + if (ar1_enc == (crypto1_word(t, 0, 0) ^ p64)) { printf("\nFound Key: [%012"llx"]\n\n",key); break;} } diff --git a/tools/mfkey/mfkey32v2.c b/tools/mfkey/mfkey32v2.c index 349b31e7..92ac371f 100644 --- a/tools/mfkey/mfkey32v2.c +++ b/tools/mfkey/mfkey32v2.c @@ -47,16 +47,20 @@ int main (int argc, char *argv[]) { // Generate lfsr succesors of the tag challenge printf("\nLFSR succesors of the tag challenge:\n"); - printf(" nt': %08x\n",prng_successor(nt0, 64)); - printf(" nt'': %08x\n",prng_successor(nt0, 96)); + uint32_t p64 = prng_successor(nt0, 64); + uint32_t p64b = prng_successor(nt1, 64); + + printf(" nt': %08x\n", p64); + printf(" nt'': %08x\n", prng_successor(p64, 32)); clock_t t1 = clock(); // Extract the keystream from the messages printf("\nKeystream used to generate {ar} and {at}:\n"); - ks2 = ar0_enc ^ prng_successor(nt0, 64); + ks2 = ar0_enc ^ p64; printf(" ks2: %08x\n",ks2); - s = lfsr_recovery32(ar0_enc ^ prng_successor(nt0, 64), 0); + s = lfsr_recovery32(ar0_enc ^ p64, 0); + for(t = s; t->odd | t->even; ++t) { lfsr_rollback_word(t, 0, 0); @@ -66,7 +70,7 @@ int main (int argc, char *argv[]) { crypto1_word(t, uid ^ nt1, 0); crypto1_word(t, nr1_enc, 1); - if (ar1_enc == (crypto1_word(t, 0, 0) ^ prng_successor(nt1, 64))) { + if (ar1_enc == (crypto1_word(t, 0, 0) ^ p64b)) { printf("\nFound Key: [%012"llx"]\n\n",key); break;} } -- 2.39.2