From cedc593528f93f4b4f1144b90d6db69bfc188459 Mon Sep 17 00:00:00 2001
From: iceman1001 <iceman@iuse.se>
Date: Fri, 26 Jan 2024 22:41:06 +0100
Subject: [PATCH] dump/info readblock loops rework

---
 client/src/cmdhfxerox.c | 83 +++++++----------------------------------
 1 file changed, 13 insertions(+), 70 deletions(-)

diff --git a/client/src/cmdhfxerox.c b/client/src/cmdhfxerox.c
index a5c83ed28..c17d94de9 100644
--- a/client/src/cmdhfxerox.c
+++ b/client/src/cmdhfxerox.c
@@ -626,6 +626,8 @@ static void xerox_print_info(uint8_t *d) {
     }
 }
 
+
+// Assumes the card is already selected.
 static int read_xerox_block(iso14b_card_select_t *card, uint8_t blockno, uint8_t *out) {
 
     if (card == NULL || out == NULL) {
@@ -640,9 +642,9 @@ static int read_xerox_block(iso14b_card_select_t *card, uint8_t blockno, uint8_t
     }
 
     // set up the read command
-    packet->flags = (ISO14B_CONNECT | ISO14B_APPEND_CRC | ISO14B_RAW);
+    packet->flags = (ISO14B_APPEND_CRC | ISO14B_RAW);
     packet->raw[packet->rawlen++] = 0x02;
-    packet->raw[packet->rawlen++] = ISO14443B_XEROX_READ_BLK;
+    packet->raw[packet->rawlen++] = (blockno < 12) ? ISO14443B_XEROX_READ_BLK : ISO14443B_XEROX_EXT_READ_BLK;
 
     // uid
     memcpy(packet->raw + packet->rawlen, card->uid, card->uidlen);
@@ -651,14 +653,10 @@ static int read_xerox_block(iso14b_card_select_t *card, uint8_t blockno, uint8_t
     // block to read
     packet->raw[packet->rawlen++] = blockno;
 
+
     int res = PM3_ESOFT;
     // read loop
     for (int retry = 0; retry < 2; retry++) {
-
-        if (retry) {
-            packet->flags = (ISO14B_APPEND_CRC | ISO14B_RAW);
-        }
-
         clearCommandBuffer();
         SendCommandNG(CMD_HF_ISO14443B_COMMAND, (uint8_t *)packet, sizeof(iso14b_raw_cmd_t) + packet->rawlen);
         PacketResponseNG resp;
@@ -693,8 +691,6 @@ static int read_xerox_block(iso14b_card_select_t *card, uint8_t blockno, uint8_t
         res = PM3_SUCCESS;
         break;
     }
-
-    switch_off_field();
     return res;
 }
 
@@ -758,6 +754,7 @@ static int CmdHFXeroxInfo(const char *Cmd) {
 
     uint8_t data[sizeof(info_blocks) * XEROX_BLOCK_SIZE] = {0};
 
+    // special blocks to read.
     for (int i = 0; i < sizeof(i); i++) {
 
         int res = read_xerox_block(&card, info_blocks[i], data + (i * XEROX_BLOCK_SIZE));
@@ -810,78 +807,24 @@ static int CmdHFXeroxDump(const char *Cmd) {
     }
 
     PrintAndLogEx(INFO, "Reading memory from tag UID " _GREEN_("%s"), sprint_hex(card.uid, card.uidlen));
+    PrintAndLogEx(INFO, "" NOLF);
 
-    uint8_t approx_len = (2 + 8 + 1);
-    iso14b_raw_cmd_t *packet = (iso14b_raw_cmd_t *)calloc(1, sizeof(iso14b_raw_cmd_t) + approx_len);
-    if (packet == NULL) {
-        PrintAndLogEx(FAILED, "failed to allocate memory");
-        return PM3_EMALLOC;
-    }
-
-    int blockno = 1;           // block 0 all zeros
     uint8_t data[256 * XEROX_BLOCK_SIZE] = {0};
 
-    // set up the read command
-    packet->flags = (ISO14B_CONNECT | ISO14B_APPEND_CRC | ISO14B_RAW);
-    packet->raw[packet->rawlen++] = 0x02;
+    uint16_t blockno = 0;
+    for (; blockno < 0x100; blockno++) {
 
-    // add one for command byte
-    packet->rawlen++;
-
-    // store uid
-    memcpy(packet->raw + packet->rawlen, card.uid, 8);
-    packet->rawlen += 8;
-
-    PrintAndLogEx(INFO, "." NOLF);
-
-    for (int retry = 0; (retry < 2 && blockno < 0x100); retry++) {
-
-        // set command: read ext mem or read mem
-        packet->raw[1]  = (blockno < 12) ? ISO14443B_XEROX_READ_BLK : ISO14443B_XEROX_EXT_READ_BLK;
-        packet->raw[10] = blockno & 0xFF;
-
-        PacketResponseNG resp;
-        clearCommandBuffer();
-        SendCommandNG(CMD_HF_ISO14443B_COMMAND, (uint8_t *)packet, sizeof(iso14b_raw_cmd_t) + packet->rawlen);
-        if (WaitForResponseTimeout(CMD_HF_ISO14443B_COMMAND, &resp, 2000) == false) {
-            continue;
-        }
-
-        if (resp.status != PM3_SUCCESS) {
-            continue;
-        }
-
-        if (resp.length < 7) {
-            PrintAndLogEx(FAILED, "retrying one more time");
-            continue;
-        }
-
-        uint8_t *d = resp.data.asBytes;
-
-        if (check_crc(CRC_14443_B, d, 7) == false) {
-            PrintAndLogEx(FAILED, "retrying one more time, CRC ( " _RED_("fail") " )");
-            continue;
-        }
-
-        if (d[0] != 0x02) {
-            PrintAndLogEx(NORMAL, "");
-            PrintAndLogEx(FAILED, "Tag returned Error %x %x", d[0], d[1]);
+        int res = read_xerox_block(&card, blockno, data + (blockno * XEROX_BLOCK_SIZE));
+        if (res != PM3_SUCCESS) {
+            PrintAndLogEx(FAILED, "Fuji/Xerox tag read failed");
             break;
         }
 
-        memcpy(data + (blockno * XEROX_BLOCK_SIZE), resp.data.asBytes + 1, XEROX_BLOCK_SIZE);
-
-        retry = 0;
-        blockno++;
-
-        PrintAndLogEx(NORMAL, "." NOLF);
-        fflush(stdout);
+        PrintAndLogEx(INPLACE, "blk %3d", blockno);
     }
 
     switch_off_field();
 
-    free(packet);
-
     PrintAndLogEx(NORMAL, "");
 
     if (blockno != 0x100) {