From: Samuele <sguerrini97@gmail.com>
Date: Thu, 22 Aug 2019 05:51:46 +0000 (+0200)
Subject: PCF7931: Print found single/consecutive block(s), fixes to block 1 check
X-Git-Url: http://cvs.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/commitdiff_plain/cfa9c98d573c5a0d35c6ce86501fc6fd57f91b81

PCF7931: Print found single/consecutive block(s), fixes to block 1 check
---

diff --git a/armsrc/pcf7931.c b/armsrc/pcf7931.c
index e3bac386..147f6fb8 100644
--- a/armsrc/pcf7931.c
+++ b/armsrc/pcf7931.c
@@ -152,8 +152,14 @@ bool IsBlock0PCF7931(uint8_t *block) {
 
 bool IsBlock1PCF7931(uint8_t *block) {
 	// assuming all RFU bits are set to 0
+
+	uint8_t rb1 = block[14] & 0x80;
+	uint8_t rfb = block[14] & 0x7f;
+	uint8_t rlb = block[15];
+
 	if (block[10] == 0 && block[11] == 0 && block[12] == 0 && block[13] == 0)
-		if((block[14] & 0x7f) <= 9 && block[15] <= 9)
+		// block 1 is sent only if (RLB >= 1 && RFB <= 1) or RB1 enabled
+		if(rfb <= rlb && rfb <= 9 && rlb <= 9 && ((rfb <= 1 && rlb >= 1) || rb1))
 			return true;
 
 	return false;
@@ -192,6 +198,7 @@ void ReadPCF7931() {
 			Dbprintf("Error, no tag or bad tag");
 			return;
 		}
+
 		// exit if too many errors during reading
 		if (tries > 50 && (2*errors > tries)) {
 			Dbprintf("Error reading the tag");
@@ -201,9 +208,11 @@ void ReadPCF7931() {
 
 		// our logic breaks if we don't get at least two blocks
 		if (n < 2) {
+			// skip if all 0s block or no blocks
 			if (n == 0 || !memcmp(tmp_blocks[0], "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", 16))
 				continue;
 
+			// add block to single blocks list
 			if (single_blocks_cnt < max_blocks) {
 				for (i = 0; i < single_blocks_cnt; ++i) {
 					if (!memcmp(single_blocks[i], tmp_blocks[0], 16)) {
@@ -213,6 +222,7 @@ void ReadPCF7931() {
 				}
 				if (j != 1) {
 					memcpy(single_blocks[single_blocks_cnt], tmp_blocks[0], 16);
+					print_result("got single block", single_blocks[single_blocks_cnt], 16);
 					single_blocks_cnt++;
 				}
 				j = 0;
@@ -222,6 +232,10 @@ void ReadPCF7931() {
 		}
 
 		Dbprintf("(dbg) got %d blocks (%d/%d found) (%d tries, %d errors)", n, found_blocks, (max_blocks == 0 ? found_blocks : max_blocks), tries, errors);
+		for (i = 0; i < n; ++i)
+		{
+			print_result("got consecutive blocks", tmp_blocks[i], 16);
+		}
 
 		i = 0;
 		if(!found_0_1) {
@@ -284,7 +298,7 @@ void ReadPCF7931() {
 			goto end;
 		}
 	}
-	while (found_blocks != max_blocks);
+	while (found_blocks < max_blocks);
 
  end:
 	Dbprintf("-----------------------------------------");