support loading of flipper zero .picopass files. Also adapted to naive detect if PACS w variable length encoded is present

client/src/cmdhficlass.c

@@ -1321,36 +1321,101 @@ static int CmdHFiClassESetBlk(const char *Cmd) {
     return PM3_SUCCESS;
 }
 
+static bool iclass_detect_new_pacs(uint8_t *d) {
+    uint8_t n = 0;
+    while (n++ < (PICOPASS_BLOCK_SIZE / 2)) {
+        if (d[n] && 
+            d[n + 1] == 0xA6) {
+            return true;
+        }
+    }
+    return false;
+}
+
+// block 7 decoder for PACS 
+static int iclass_decode_credentials_new_pacs(uint8_t *d) {
+
+    uint8_t offset = 0;
+    while(d[offset] == 0 && (offset < PICOPASS_BLOCK_SIZE / 2)) {
+        offset++;
+    }
+
+    uint8_t pad = d[offset];
+
+    PrintAndLogEx(INFO, "%u , %u", offset, pad);
+
+    char *binstr = (char *)calloc((PICOPASS_BLOCK_SIZE * 8) + 1, sizeof(uint8_t));
+    if (binstr == NULL) {
+        return PM3_EMALLOC;
+    }
+
+    uint8_t n = PICOPASS_BLOCK_SIZE - offset - 2;    
+    byte_2_binstr(binstr, d + offset + 2, n);
+
+    PrintAndLogEx(NORMAL, "");
+    PrintAndLogEx(SUCCESS, "PACS......... " _GREEN_("%s"), sprint_hex_inrow(d + offset + 2, n));
+    PrintAndLogEx(SUCCESS, "padded bin... " _GREEN_("%s") " ( %zu )", binstr, strlen(binstr));
+
+    binstr[strlen(binstr) - pad] = '\0';
+    PrintAndLogEx(SUCCESS, "bin.......... " _GREEN_("%s") " ( %zu )", binstr, strlen(binstr));
+
+    size_t hexlen = 0;
+    uint8_t hex[16] = {0};
+    binstr_2_bytes(hex, &hexlen, binstr);
+    PrintAndLogEx(SUCCESS, "hex.......... " _GREEN_("%s"), sprint_hex_inrow(hex, hexlen));
+
+    uint32_t top = 0, mid = 0, bot = 0;
+    if (binstring_to_u96(&top, &mid, &bot, binstr) != strlen(binstr)) {
+        PrintAndLogEx(ERR, "Binary string contains none <0|1> chars");
+        free(binstr);
+        return PM3_EINVARG;
+    }
+
+    PrintAndLogEx(NORMAL, "");
+    PrintAndLogEx(INFO, "Wiegand decode");
+    wiegand_message_t packed = initialize_message_object(top, mid, bot, 0);
+    HIDTryUnpack(&packed);
+}
+
 static void iclass_decode_credentials(uint8_t *data) {
     picopass_hdr_t *hdr = (picopass_hdr_t *)data;
-    if (memcmp(hdr->app_issuer_area, "\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF", PICOPASS_BLOCK_SIZE)) {
+    if (memcmp(hdr->app_issuer_area, empty, PICOPASS_BLOCK_SIZE)) {
         // Not a Legacy or SR card, nothing to do here.
         return;
     }
 
-    BLOCK79ENCRYPTION encryption = (data[(6 * 8) + 7] & 0x03);
+    BLOCK79ENCRYPTION encryption = (data[(6 * PICOPASS_BLOCK_SIZE) + 7] & 0x03);
-    bool has_values = (memcmp(data + (8 * 7), empty, 8) != 0) && (memcmp(data + (8 * 7), zeros, 8) != 0);
+
+    uint8_t *b7 = data + (PICOPASS_BLOCK_SIZE * 7);
+
+    bool has_new_pacs = iclass_detect_new_pacs(b7);
+    bool has_values = (memcmp(b7, empty, PICOPASS_BLOCK_SIZE) != 0) && (memcmp(b7, zeros, PICOPASS_BLOCK_SIZE) != 0);
     if (has_values && encryption == None) {
 
-        //todo:  remove preamble/sentinel
+        // todo:  remove preamble/sentinel
-        uint32_t top = 0, mid = 0, bot = 0;
-
         PrintAndLogEx(INFO, "Block 7 decoder");
 
-        char hexstr[16 + 1] = {0};
+        if (has_new_pacs) {
-        hex_to_buffer((uint8_t *)hexstr, data + (8 * 7), 8, sizeof(hexstr) - 1, 0, 0, true);
+            iclass_decode_credentials_new_pacs(b7);
-        hexstring_to_u96(&top, &mid, &bot, hexstr);
+        } else {
+            char hexstr[16 + 1] = {0};
+            hex_to_buffer((uint8_t *)hexstr, b7, PICOPASS_BLOCK_SIZE, sizeof(hexstr) - 1, 0, 0, true);
 
-        char binstr[64 + 1];
+            uint32_t top = 0, mid = 0, bot = 0;
-        hextobinstring(binstr, hexstr);
+            hexstring_to_u96(&top, &mid, &bot, hexstr);
-        char *pbin = binstr;
-        while (strlen(pbin) && *(++pbin) == '0');
 
-        PrintAndLogEx(SUCCESS, "Binary..................... " _GREEN_("%s"), pbin);
+            char binstr[64 + 1];
+            hextobinstring(binstr, hexstr);
+            char *pbin = binstr;
+            while (strlen(pbin) && *(++pbin) == '0');
+
+            PrintAndLogEx(SUCCESS, "Binary..................... " _GREEN_("%s"), pbin);
+
+            PrintAndLogEx(INFO, "Wiegand decode");
+            wiegand_message_t packed = initialize_message_object(top, mid, bot, 0);
+            HIDTryUnpack(&packed);
+        }
 
-        PrintAndLogEx(INFO, "Wiegand decode");
-        wiegand_message_t packed = initialize_message_object(top, mid, bot, 0);
-        HIDTryUnpack(&packed);
     } else {
         PrintAndLogEx(INFO, "No unencrypted legacy credential found");
     }

client/src/fileutils.c

@@ -87,7 +87,9 @@ DumpFileType_t getfiletype(const char *filename) {
         } else if (str_endswith(s, "mct")) {
             o = MCT;
         } else if (str_endswith(s, "nfc")) {
-            o = NFC;
+            o = FLIPPER;
+        } else if (str_endswith(s, "picopass")) {
+            o = FLIPPER;
         } else {
             // mfd, trc, trace is binary
             o = BIN;
@@ -1020,7 +1022,7 @@ int loadFileNFC_safe(const char *preferredName, void *data, size_t maxdatalen, s
     int retval = PM3_SUCCESS;
 
     char *path;
-    int res = searchFile(&path, RESOURCES_SUBDIR, preferredName, ".nfc", false);
+    int res = searchFile(&path, RESOURCES_SUBDIR, preferredName, "", false);
     if (res != PM3_SUCCESS) {
         return PM3_EFILE;
     }
@@ -1221,14 +1223,18 @@ int loadFileNFC_safe(const char *preferredName, void *data, size_t maxdatalen, s
                 uint8_t block[MFBLOCK_SIZE] = {0};
                 param_gethex_to_eol(p, 0, block, MFBLOCK_SIZE, &n);
                 memcpy(&udata.bytes[(blockno * MFBLOCK_SIZE)], block, MFBLOCK_SIZE);
+            } else if (ft == NFC_DF_PICOPASS) {
+                uint8_t block[PICOPASS_BLOCK_SIZE] = {0};
+                param_gethex_to_eol(p, 0, block, PICOPASS_BLOCK_SIZE, &n);
+                memcpy(&udata.bytes[(blockno * PICOPASS_BLOCK_SIZE)], block, PICOPASS_BLOCK_SIZE);
             }
-            counter += MFBLOCK_SIZE;
+            counter += PICOPASS_BLOCK_SIZE;
             continue;
         }
     }
 
     // add header length
-    if (ft == NFC_DF_MFC) {
+    if (ft == NFC_DF_MFC || ft == NFC_DF_PICOPASS) {
         *datalen = counter;
     } else if (ft == NFC_DF_MFU) {
         *datalen += MFU_DUMP_PREFIX_LENGTH;
@@ -1382,6 +1388,7 @@ int loadFileJSONex(const char *preferredName, void *data, size_t maxdatalen, siz
     }
 
     udata_t udata = (udata_t)data;
+
     size_t len = 0;
     char blocks[PATH_MAX_LENGTH] = {0};
 
@@ -2278,7 +2285,12 @@ nfc_df_e detect_nfc_dump_format(const char *preferredName, bool verbose) {
         if (str_startswith(line, "device type: iso14443-4a")) {
             retval = NFC_DF_14_4A;
             break;
-        }              
+        }
+        if (str_startswith(line, "filetype: flipper picopass device")) {
+            retval = NFC_DF_PICOPASS;
+            break;
+        }
+
     }
     fclose(f);
 
@@ -2302,6 +2314,9 @@ nfc_df_e detect_nfc_dump_format(const char *preferredName, bool verbose) {
             case NFC_DF_14_4A:
                 PrintAndLogEx(INFO, "detected ISO14443-4A based dump format. No data available");
                 break;
+            case NFC_DF_PICOPASS:
+                PrintAndLogEx(INFO, "detected PICOPASS based dump format");
+                break; 
             case NFC_DF_UNKNOWN:
                 PrintAndLogEx(WARNING, "failed to detected dump format");
                 break;
@@ -2757,9 +2772,9 @@ int pm3_load_dump(const char *fn, void **pdump, size_t *dumplen, size_t maxdumpl
             res = loadFileMCT_safe(fn, pdump, dumplen);
             break;
         }
-        case NFC: {
+        case FLIPPER: {
             nfc_df_e foo = detect_nfc_dump_format(fn, true);
-            if (foo == NFC_DF_MFC || foo == NFC_DF_MFU) {
+            if (foo == NFC_DF_MFC || foo == NFC_DF_MFU || foo == NFC_DF_PICOPASS) {
 
                 if (foo == NFC_DF_MFC) {
                     *pdump = calloc(maxdumplen, sizeof(uint8_t));

client/src/fileutils.h

@@ -79,7 +79,7 @@ typedef enum {
     JSON,
     DICTIONARY,
     MCT,
-    NFC,
+    FLIPPER,
 } DumpFileType_t;
 
 typedef enum {
@@ -96,7 +96,8 @@ typedef enum {
     NFC_DF_MFDES,
     NFC_DF_14_3A,
     NFC_DF_14_3B,
-    NFC_DF_14_4A
+    NFC_DF_14_4A,
+    NFC_DF_PICOPASS,
 } nfc_df_e;
 
 int fileExists(const char *filename);