Update cmdhf14a.c

[proxmark3-svn] / client / mifarehost.c

diff --git a/client/mifarehost.c b/client/mifarehost.c
index 6b5e3ba2312df8e4a9742ff45a09a08b21e5411a..51dd73744609e9543924eeadb9e77ae1032220b1 100644 (file)
--- a/client/mifarehost.c
+++ b/client/mifarehost.c
@@ -820,3 +820,33 @@ int tryDecryptWord(uint32_t nt, uint32_t ar_enc, uint32_t at_enc, uint8_t *data,
        crypto1_destroy(traceCrypto1);\r
        return 0;\r
 }\r
        crypto1_destroy(traceCrypto1);\r
        return 0;\r
 }\r

+/* Detect Tag Prng, \r
+* function performs a partial AUTH,  where it tries to authenticate against block0, key A, but only collects tag nonce.\r
+* the tag nonce is check to see if it has a predictable PRNG.\r
+* @returns \r
+*      TRUE if tag uses WEAK prng (ie Darkside attack possible)\r
+*   FALSE is tag uses HARDEND prng (ie hardnested attack possible, with known key)\r
+*/\r
+bool detect_classic_prng(){\r
+\r
+       UsbCommand resp, respA; \r
+       uint8_t cmd[] = {MIFARE_AUTH_KEYA, 0x00};\r
+       uint32_t flags = ISO14A_CONNECT | ISO14A_RAW | ISO14A_APPEND_CRC;\r
+       \r
+       UsbCommand cAuth = {CMD_READER_ISO_14443a, {flags, sizeof(cmd), 0}};\r
+       memcpy(cAuth.d.asBytes, cmd, sizeof(cmd));\r
+\r
+       clearCommandBuffer();\r
+       SendCommand(&cAuth);\r
+       WaitForResponse(CMD_ACK, &resp);\r
+       WaitForResponse(CMD_ACK, &respA);\r
+               \r
+       // if select tag failed.\r
+       if ( resp.arg[0] == 0 ) {\r
+               printf("Error:  selecting tag failed,  can't detect prng\n");\r
+               return false;\r
+       }\r
+\r
+       uint32_t nonce = bytes_to_num(respA.d.asBytes, respA.arg[0]);\r
+       return validate_prng_nonce(nonce);\r
+}\r