Iso7816Exchange: avoid sending systematically typeA APDUs firstly on typeB tags

client/src/cmdhf14b.c

@@ -42,6 +42,7 @@ bool apdu_in_framing_enable = true;
 static int CmdHelp(const char *Cmd);
 
 static int switch_off_field_14b(void) {
+    SetISODEPState(ISODEP_INACTIVE);
     iso14b_raw_cmd_t packet = {
         .flags = ISO14B_DISCONNECT,
         .timeout = 0,

client/src/cmdhfcryptorf.c

@@ -17,7 +17,6 @@
 #include "comms.h"        // clearCommandBuffer
 #include "cmdtrace.h"
 #include "crc16.h"
-#include "cmdhf14a.h"
 #include "protocols.h"    // definitions of ISO14B protocol
 #include "iso14b.h"
 #include "cliparser.h"    // cliparsing
@@ -36,6 +35,7 @@ static void set_last_known_card(iso14b_card_select_t card) {
 }
 
 static int switch_off_field_cryptorf(void) {
+    SetISODEPState(ISODEP_INACTIVE);
     iso14b_raw_cmd_t packet = {
         .flags = ISO14B_DISCONNECT,
         .timeout = 0,

client/src/cmdhflto.c

@@ -94,6 +94,7 @@ static const char *get_page_name(uint16_t pageid) {
 static int CmdHelp(const char *Cmd);
 
 static void lto_switch_off_field(void) {
+    SetISODEPState(ISODEP_INACTIVE);
     SendCommandMIX(CMD_HF_ISO14443A_READER, 0, 0, 0, NULL, 0);
 }
 

client/src/cmdhftopaz.c

@@ -49,6 +49,7 @@ static void topaz_switch_on_field(void) {
 }
 
 static void topaz_switch_off_field(void) {
+    SetISODEPState(ISODEP_INACTIVE);
     SendCommandMIX(CMD_HF_ISO14443A_READER, 0, 0, 0, NULL, 0);
 }
 

client/src/comms.h

@@ -15,13 +15,14 @@
 #include "common.h"
 #include "pm3_cmd.h"    // Packet structs
 #include "util.h"       // FILE_PATH_SIZE
+#include "iso7816/iso7816core.h" // SetISODEPState
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
 #ifndef DropField
-#define DropField() { clearCommandBuffer(); SendCommandNG(CMD_HF_DROPFIELD, NULL, 0); }
+#define DropField() { clearCommandBuffer(); SetISODEPState(ISODEP_INACTIVE); SendCommandNG(CMD_HF_DROPFIELD, NULL, 0); }
 #endif
 
 #ifndef DropFieldEx

client/src/iso7816/iso7816core.c

@@ -31,6 +31,16 @@ bool GetAPDULogging(void) {
     return APDULogging;
 }
 
+static isodep_state_t isodep_state = ISODEP_INACTIVE;
+
+void SetISODEPState(isodep_state_t state) {
+    isodep_state = state;
+}
+
+isodep_state_t GetISODEPState(void) {
+    return isodep_state;
+}
+
 int Iso7816ExchangeEx(Iso7816CommandChannel channel, bool ActivateField, bool LeaveFieldON, sAPDU apdu, bool IncludeLe, uint8_t *Result, size_t MaxResultLen, size_t *ResultLen, uint16_t *sw) {
     uint8_t data[APDU_RES_LEN] = {0};
 
@@ -56,10 +66,25 @@ int Iso7816ExchangeEx(Iso7816CommandChannel channel, bool ActivateField, bool Le
 
     switch (channel) {
         case CC_CONTACTLESS:
+            switch (GetISODEPState()) {
+                case ISODEP_NFCA:
+                    res = ExchangeAPDU14a(data, datalen, ActivateField, LeaveFieldON, Result, (int)MaxResultLen, (int *)ResultLen);
+                    break;
+                case ISODEP_NFCB:
+                    res = exchange_14b_apdu(data, datalen, ActivateField, LeaveFieldON, Result, (int)MaxResultLen, (int *)ResultLen, 4000);
+                    break;
+                case ISODEP_INACTIVE:
+                    if (! ActivateField) {
+                        PrintAndLogEx(FAILED, "Field currently inactive, cannot send an APDU");
+                        return PM3_EIO;
+                    }
                     res = ExchangeAPDU14a(data, datalen, ActivateField, LeaveFieldON, Result, (int)MaxResultLen, (int *)ResultLen);
                     if (res != PM3_SUCCESS) {
                         res = exchange_14b_apdu(data, datalen, ActivateField, LeaveFieldON, Result, (int)MaxResultLen, (int *)ResultLen, 4000);
-                if (res != PM3_SUCCESS)
+                    }
+                    break;
+            }
+            if (res != PM3_SUCCESS) {
                 return res;
             }
             break;

client/src/iso7816/iso7816core.h

@@ -20,6 +20,12 @@
 #define APDU_RES_LEN 260
 #define APDU_AID_LEN 50
 
+typedef enum {
+    ISODEP_INACTIVE = 0,
+    ISODEP_NFCA,
+    ISODEP_NFCB,
+} isodep_state_t;
+
 typedef enum {
     CC_CONTACTLESS,
     CC_CONTACT
@@ -28,6 +34,9 @@ typedef enum {
 void SetAPDULogging(bool logging);
 bool GetAPDULogging(void);
 
+void SetISODEPState(isodep_state_t state);
+isodep_state_t GetISODEPState(void);
+
 // exchange
 int Iso7816Exchange(Iso7816CommandChannel channel, bool LeaveFieldON, sAPDU apdu, uint8_t *Result, size_t MaxResultLen, size_t *ResultLen, uint16_t *sw);
 int Iso7816ExchangeEx(Iso7816CommandChannel channel, bool ActivateField, bool LeaveFieldON, sAPDU apdu, bool IncludeLe, uint8_t *Result, size_t MaxResultLen, size_t *ResultLen, uint16_t *sw);