Add support for standard USB Smartcard Readers (#765)

* add PCSC interface (pcsc.c and pcsc.h)
* new command 'sc select' to choose an USB Smartcard Reader
* updated CI/.travis.yml accordingly
* remove TCK CRC check in i2c.c It is done in PrintATR() anyway
* Fix TCK CRC check in PrintATR()
* Add PCSC reader support to 'sc info'

client/pcsc.c

@@ -0,0 +1,177 @@
+//-----------------------------------------------------------------------------
+// Copyright (C) 2019 piwi
+//
+// This code is licensed to you under the terms of the GNU GPL, version 2 or,
+// at your option, any later version. See the LICENSE.txt file for the text of
+// the license.
+//-----------------------------------------------------------------------------
+// PCSC functions to use alternative Smartcard Readers
+//-----------------------------------------------------------------------------
+
+#include "pcsc.h"
+
+#include <stdlib.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <string.h>
+
+#if defined (__APPLE__)
+#include <PCSC/winscard.h>
+#include <PCSC/wintypes.h>
+#define SCARD_ATTR_VALUE(Class, Tag) ((((ULONG)(Class)) << 16) | ((ULONG)(Tag)))
+#define SCARD_CLASS_ICC_STATE       9 
+#define SCARD_ATTR_ATR_STRING SCARD_ATTR_VALUE(SCARD_CLASS_ICC_STATE, 0x0303)
+#elif defined (_WIN32)
+#include <winscard.h>
+#else
+#include <winscard.h>
+#include <reader.h>
+#endif
+
+#include "ui.h"
+#include "util.h"
+#include "cmdhw.h"
+
+static SCARDCONTEXT SC_Context;
+static SCARDHANDLE SC_Card;
+static DWORD SC_Protocol;
+static char* AlternativeSmartcardReader = NULL;
+
+
+char *getAlternativeSmartcardReader(void)
+{
+	return AlternativeSmartcardReader;
+}
+
+
+bool pcscCheckForCardReaders(void)
+{
+	LONG res = SCardEstablishContext(SCARD_SCOPE_SYSTEM, NULL, NULL, &SC_Context);
+	if (res != SCARD_S_SUCCESS) {
+		return false;
+	}
+
+	DWORD pcchReaders;
+	res = SCardListReaders(SC_Context, NULL, NULL, &pcchReaders);
+	if (res != SCARD_S_SUCCESS) {
+		SCardReleaseContext(SC_Context);
+		return false;
+	}
+
+	if (res == SCARD_E_NO_READERS_AVAILABLE || res == SCARD_E_NO_SERVICE) {
+		SCardReleaseContext(SC_Context);
+		return false;
+	}
+	
+	return true;
+}
+
+
+static char *pickReader(LPTSTR readerlist)
+{
+	PrintAndLogEx(NORMAL, "Please select one of these:");
+	PrintAndLogEx(NORMAL, "  [0] PM3 RDV40 Smartcard Slot %s", PM3hasSmartcardSlot() ? "(default)" : "(default, not available)");
+
+	int num = 1;
+	for (LPTSTR p = readerlist; *p != '\0'; ) {
+		PrintAndLogEx(NORMAL, "  [%1d] %s", num++, p);
+		while (*p++ != '\0') ; // advance to next entry
+	}
+
+	num--;
+	
+	if (num == 1) {
+		printf("Your choice (0 or 1)?");
+	} else {
+		printf("Your choice (0...%d)? ", num);
+	}
+	int selection = getch() - '0';
+	printf("\n");	
+
+	if (selection == 0) {
+		PrintAndLogEx(INFO, "Selected RDV40 Smartcard Slot");
+		return NULL;
+	}
+
+	if (selection >= 1 && selection <= num) {
+		LPTSTR p = readerlist;
+		for (int i = 1; i < selection; i++) {
+			while (*p++ != '\0') ; // advance to next entry
+		}
+		PrintAndLogEx(INFO, "Selected %s", p);
+		return p;
+	}
+
+	PrintAndLogEx(INFO, "Invalid selection. Using RDV40 Smartcard Slot");
+	return NULL;
+	
+}
+
+
+char *matchString(LPTSTR readerlist, const char *readername)
+{
+	return pickReader(readerlist);
+}
+
+	
+bool pcscSelectAlternativeCardReader(const char *readername)
+{
+	DWORD readerlist_len;
+	LONG res = SCardListReaders(SC_Context, NULL, NULL, &readerlist_len);
+	if (res != SCARD_S_SUCCESS) {
+		return false;
+	}
+
+	LPTSTR readerlist = calloc(readerlist_len, sizeof(char));
+	res = SCardListReaders(SC_Context, NULL, readerlist, &readerlist_len);
+	if (res != SCARD_S_SUCCESS) {
+		free(readerlist);
+		return false;
+	}
+
+	char *selected_readername = NULL;
+	if (readername) {
+		selected_readername = matchString(readerlist, readername);
+	} else {
+		selected_readername = pickReader(readerlist);
+	}
+
+	if (selected_readername == NULL) {
+		free(readerlist);
+		return false;
+	}
+
+	free(AlternativeSmartcardReader);
+	AlternativeSmartcardReader = malloc((strlen(selected_readername) + 1) * sizeof(char));
+	strcpy(AlternativeSmartcardReader, selected_readername);
+	
+	return true;
+}
+
+
+bool pcscGetATR(smart_card_atr_t *card)
+{
+	if (!card) {
+		return false;
+	}
+	
+	card->atr_len = 0;
+	memset(card->atr, 0, sizeof(card->atr));
+
+	LONG res = SCardConnect(SC_Context, AlternativeSmartcardReader, SCARD_SHARE_SHARED,
+	                        SCARD_PROTOCOL_T0 | SCARD_PROTOCOL_T1, &SC_Card, &SC_Protocol);
+	if (res != SCARD_S_SUCCESS) {
+		return false;
+	}
+
+	DWORD atr_len = sizeof(card->atr);
+	res = SCardGetAttrib(SC_Card, SCARD_ATTR_ATR_STRING, card->atr, &atr_len);
+	if (res != SCARD_S_SUCCESS) {
+		return false;
+	}
+	card->atr_len = atr_len;
+	
+	// TODO: LogTrace without device
+	
+	return true;	
+}