Some more refinements

[proxmark3-svn] / client / cmdhfmf.c

diff --git a/client/cmdhfmf.c b/client/cmdhfmf.c
index 24d04dc2de934753a56a286f7c27e2d63519ef00..f225359d7d8801cfb4e053f0d47bce73e1f831e1 100644 (file)
--- a/client/cmdhfmf.c
+++ b/client/cmdhfmf.c
@@ -1765,15 +1765,16 @@ int CmdHF14AMfSniff(const char *Cmd){
        int res = 0;\r
        int len = 0;\r
        int blockLen = 0;\r
-       int num = 0;\r
        int pckNum = 0;\r
-       uint8_t uid[7] = {0x00};\r
+       int num = 0;\r
+       uint8_t uid[7];\r
        uint8_t uid_len;\r
        uint8_t atqa[2] = {0x00};\r
        uint8_t sak;\r
        bool isTag;\r
-       uint8_t buf[3000] = {0x00};\r
-       uint8_t * bufPtr = buf;\r
+       uint8_t *buf = NULL;\r
+       uint16_t bufsize = 0;\r
+       uint8_t *bufPtr = NULL;\r
        \r
        char ctmp = param_getchar(Cmd, 0);\r
        if ( ctmp == 'h' || ctmp == 'H' ) {\r
@@ -1816,32 +1817,47 @@ int CmdHF14AMfSniff(const char *Cmd){
                        break;\r
                }\r
                \r
-    UsbCommand resp;\r
-    if (WaitForResponseTimeout(CMD_ACK,&resp,2000)) {\r
+               UsbCommand resp;\r
+               if (WaitForResponseTimeout(CMD_ACK,&resp,2000)) {\r
                        res = resp.arg[0] & 0xff;\r
-                       len = resp.arg[1];\r
-                       num = resp.arg[2];\r
-                       \r
-                       if (res == 0) return 0;\r
-                       if (res == 1) {\r
-                               if (num ==0) {\r
+                       uint16_t traceLen = resp.arg[1];\r
+                       len = resp.arg[2];\r
+\r
+                       if (res == 0) return 0;                                         // we are done\r
+\r
+                       if (res == 1) {                                                         // there is (more) data to be transferred\r
+                               if (pckNum == 0) {                                              // first packet, (re)allocate necessary buffer\r
+                                       if (traceLen > bufsize) {\r
+                                               uint8_t *p;\r
+                                               if (buf == NULL) {                              // not yet allocated\r
+                                                       p = malloc(traceLen);\r
+                                               } else {                                                // need more memory\r
+                                                       p = realloc(buf, traceLen);\r
+                                               }\r
+                                               if (p == NULL) {\r
+                                                       PrintAndLog("Cannot allocate memory for trace");\r
+                                                       free(buf);\r
+                                                       return 2;\r
+                                               }\r
+                                               buf = p;\r
+                                       }\r
                                        bufPtr = buf;\r
-                                       memset(buf, 0x00, 3000);\r
+                                       bufsize = traceLen;\r
+                                       memset(buf, 0x00, traceLen);\r
                                }\r
                                memcpy(bufPtr, resp.d.asBytes, len);\r
                                bufPtr += len;\r
                                pckNum++;\r
                        }\r
-                       if (res == 2) {\r
+\r
+                       if (res == 2) {                                                         // received all data, start displaying\r
                                blockLen = bufPtr - buf;\r
                                bufPtr = buf;\r
                                printf(">\n");\r
                                PrintAndLog("received trace len: %d packages: %d", blockLen, pckNum);\r
-                               num = 0;\r
                                while (bufPtr - buf < blockLen) {\r
-                                       bufPtr += 6;\r
+                                       bufPtr += 6;                                            // skip (void) timing information\r
                                        len = *((uint16_t *)bufPtr);\r
-\r
                                        if(len & 0x8000) {\r
                                                isTag = true;\r
                                                len &= 0x7fff;\r
@@ -1850,12 +1866,10 @@ int CmdHF14AMfSniff(const char *Cmd){
                                        }\r
                                        bufPtr += 2;\r
                                        if ((len == 14) && (bufPtr[0] == 0xff) && (bufPtr[1] == 0xff) && (bufPtr[12] == 0xff) && (bufPtr[13] == 0xff)) {\r
-                                       \r
                                                memcpy(uid, bufPtr + 2, 7);\r
                                                memcpy(atqa, bufPtr + 2 + 7, 2);\r
                                                uid_len = (atqa[0] & 0xC0) == 0x40 ? 7 : 4;\r
                                                sak = bufPtr[11];\r
-                                               \r
                                                PrintAndLog("tag select uid:%s atqa:0x%02x%02x sak:0x%02x", \r
                                                        sprint_hex(uid + (7 - uid_len), uid_len),\r
                                                        atqa[1], \r
@@ -1873,18 +1887,21 @@ int CmdHF14AMfSniff(const char *Cmd){
                                                        AddLogHex(logHexFileName, isTag ? "TAG: ":"RDR: ", bufPtr, len);\r
                                                if (wantDecrypt) \r
                                                        mfTraceDecode(bufPtr, len, wantSaveToEmlFile);\r
+                                               num++;  \r
                                        }\r
                                        bufPtr += len;\r
                                        bufPtr += ((len-1)/8+1);        // ignore parity\r
-                                       num++;\r
                                }\r
+                               pckNum = 0;\r
                        }\r
                } // resp not NULL\r
        } // while (true)\r
-       \r
+\r
+       free(buf);\r
        return 0;\r
 }\r
 \r
+\r
 static command_t CommandTable[] =\r
 {\r
   {"help",             CmdHelp,                                1, "This help"},\r