[HSM] Add debugging functions

build/gcc/Makefile

@@ -71,6 +71,7 @@ TARGET = nitrokey-hsm-firmware
 # List C source files here. (C dependencies are automatically generated.)
 # use file-extension c for "c-only"-files
 SRC = 		../../src/main.c                                         \
+			../../src/debug.c                                         \
 			../../src/hw_config.c                                         \
 			../../src/test_code.c                                         \
 			../../src/utils/delays.c	\

debug.py

@@ -0,0 +1,31 @@
+import usb.core
+import sys
+import time
+
+# This script waits for a Nitrokey HSM in debug mode to be attached
+# and prints all debug output. Timeouts are ignored. All other 
+# communication errors produce an error message and the script
+# continues by waiting for a device to be attached.
+# Make sure the script is running before the Nitrokey is attached
+# to prevent timeouts in other applications.
+
+while True:
+	# TODO: Other device types
+	dev = usb.core.find(idVendor=0x20a0, idProduct=0x4230)
+	if dev is None:
+    		time.sleep(0.01)
+    		continue
+	dev.set_configuration()
+	print "DEVICE ATTACHED, LOGGING:"
+	while True:
+		try:
+			bytes = dev.read(0x85, 32)
+			sys.stdout.write(bytes.tostring())
+			sys.stdout.flush()
+		except usb.core.USBError as e:
+			if e[0] == 110:
+				continue
+			print "COMMUNICATION ERROR:"
+			print e
+			break
+

src/ccid/CCIDHID_USB/CCIDHID_usb_desc.c

@@ -59,7 +59,7 @@ const uint8_t CCID_ConfigDescriptor[CCID_SIZ_CONFIG_DESC] = {
     0x09,   /* bLength ConfigDescriptor */
     0x02,   /* bDescriptorType */
     CCID_SIZ_CONFIG_DESC,  0x00, /* uint16_t wTotalLength */
-    0x01,   /* bNumInterfaces */
+    0x02,   /* bNumInterfaces */
     0x01,   /* bConfigurationValue */
     0x00,   /* iConfiguration CCID = 6 ???? */
     USB_CONFIG_BUS_POWERED, /* bmAttributes */
@@ -149,7 +149,25 @@ const uint8_t CCID_ConfigDescriptor[CCID_SIZ_CONFIG_DESC] = {
     0x00,   // wMaxPacketSize (MSB)
     0x00,   // bInterval: ignored
 
+    // Interface 1 descriptor (Interface 1 = Debug interface)
+    0x09,   /* bLength */
+    0x04,   /* bDescriptorType */
+    0x01,   /* bInterfaceNumber */
+    0x00,   /* bAlternateSetting */
+    0x01,   /* bNumEndpoints = 1 */
+    0xFF,   /* bInterfaceClass = Vendor specific */
+    0x00,   /* bInterfaceSubClass */
+    0x00,   /* bInterfaceProtocol */
+    0x00,   /* iInterface Index of string descriptor */
 
+    // Endpoint 5 descriptor (Interrupt IN for debug)
+    0x07,   /* bLength */
+    0x05,   // bDescriptorType: Endpoint descriptor type
+    0x85,   // bEndpointAddress: Endpoint 5 IN
+    0x03,   // bmAttributes: Interrupt endpoint
+    0x20,   // wMaxPacketSize(LSB): 32 byte
+    0x00,   // wMaxPacketSize (MSB)
+    0x18,   // bInterval: Polling Interval (24 ms = 0x18)
 };
 
 

src/ccid/CCIDHID_USB/CCIDHID_usb_prop.c

@@ -217,6 +217,12 @@ void USB_CCID_Reset (void)
     SetEPRxStatus (ENDP4, EP_RX_DIS);
     SetEPTxStatus (ENDP4, EP_TX_NAK);
 
+    /* Initialize Endpoint 5 */
+    SetEPType (ENDP5, EP_INTERRUPT);
+    SetEPTxAddr (ENDP5, ENDP5_TXADDR);
+    SetEPTxStatus (ENDP5, EP_TX_NAK);
+    SetEPRxStatus (ENDP5, EP_RX_DIS);
+
     /* */
     SetEPRxCount (ENDP0, Device_Property->MaxPacketSize);
     SetEPRxValid (ENDP0);

src/debug.c

@@ -0,0 +1,49 @@
+#include <stdarg.h>
+#include <stdio.h>
+#include "usb_lib.h"
+#include "CCIDHID_usb_conf.h"
+#include "CCIDHID_usb_desc.h"
+#include "usb_pwr.h"
+#include "usb_bot.h"
+#include "hw_config.h"
+#include "CCIDHID_usb_prop.h"
+#include "CCIDHID_usb.h"
+#include "debug.h"
+
+__IO uint8_t DebugTransferComplete;
+
+void Debug(uint8_t *buffer, size_t length) {
+#ifdef DBG
+  // Split buffer into transfers of length 32 or less, which are
+  // sent to the host individually.
+  while (length != 0) {
+    // Determine next transfer length (32 bytes or less)
+    size_t messageLength = 32;
+    if (length < messageLength)
+      messageLength = length;
+    // Start transfer
+    DebugTransferComplete = 0;
+    UserToPMABufferCopy(buffer, ENDP5_TXADDR, messageLength);
+    SetEPTxCount(ENDP5, messageLength);
+    SetEPTxStatus(ENDP5, EP_TX_VALID);
+    // Wait for content to arrive at host
+    while (DebugTransferComplete == 0)
+      ;
+    // Move forward in buffer
+    length -= messageLength;
+    buffer += messageLength;
+  }
+#endif
+}
+
+void Debugf(const char *format, ...) {
+#ifdef DBG
+  char buffer[512];
+  va_list args;
+  va_start(args, format);
+  int length = vsnprintf(buffer, 512, format, args);
+  va_end(args);
+  if (length > 0)
+    Debug((uint8_t *)buffer, (size_t)length);
+#endif
+}

src/inc/CCIDHID_usb_desc.h

@@ -30,7 +30,7 @@
 /* Exported macro ------------------------------------------------------------ */
 /* Exported define ----------------------------------------------------------- */
 #define CCID_SIZ_DEVICE_DESC              18
-#define CCID_SIZ_CONFIG_DESC              (9 + 9 + 0x36 + 3*0x07)
+#define CCID_SIZ_CONFIG_DESC              (9 + 9 + 0x36 + 3*7 + 9 + 7)
 // #define CCID_SIZ_CONFIG_DESC (1*0x09 + 3*0x09 +0x36 + 4*0x07)
 // #define CCID_SIZ_CONFIG_DESC (3*0x09 +2*0x36 + 6*0x07)
 

src/inc/debug.h

@@ -0,0 +1,19 @@
+#ifndef DEBUG_H
+#define DEBUG_H
+#include <stddef.h>
+
+// Uncomment the following line to enable debugging.
+// If debugging is enabled, the host must listen to
+// interrupt transfers on endpoint 5.
+// #define DBG
+
+// Sends the buffer contents as a series of interrupt
+// transfers. All transfers are guaranteed to arrive
+// before execution continues.
+void Debug(uint8_t *buffer, size_t length);
+
+// Wrapper for Debug with the same prototype as printf.
+// Sends only up to 512 bytes. The remaining bytes are
+// ignored. See Debug for more details.
+void Debugf(const char *format, ...);
+#endif

src/inc/usb_conf.h

@@ -27,7 +27,7 @@
 /* EP_NUM */
 /* defines how many endpoints are used by the device */
 /*-------------------------------------------------------------*/
-#define EP_NUM                          (5)
+#define EP_NUM                          (6)
 
 /*-------------------------------------------------------------*/
 /* -------------- Buffer Description Table ----------------- */
@@ -56,6 +56,9 @@
 // #define ENDP3_TXADDR (0x158)
 #define ENDP4_TXADDR        (0x19C)
 
+/* EP5 */
+/* tx buffer base address */
+#define ENDP5_TXADDR        (0x1DC)
 
 /* ISTR events */
 /* IMR_MSK */
@@ -72,7 +75,7 @@
 // #define EP2_IN_Callback NOP_Process
 #define  EP3_IN_Callback   NOP_Process
 // #define EP4_IN_Callback NOP_Process
-#define  EP5_IN_Callback   NOP_Process
+// #define  EP5_IN_Callback   NOP_Process
 #define  EP6_IN_Callback   NOP_Process
 #define  EP7_IN_Callback   NOP_Process
 

src/main.c

@@ -35,6 +35,7 @@
 #include "string.h"
 #include "CcidLocalAccess.h"
 #include "HandleAesStorageKey.h"
+#include "debug.h"
 
 
 
@@ -127,6 +128,7 @@ int main (void)
     StartupCheck_u8 ();
 
     /* Endless loop after USB startup */
+    Debugf("Entering loop after USB startup\n");
     while (1)
     {
         if (device_status == STATUS_RECEIVED_REPORT)

src/usb/usb_endp.c

@@ -32,6 +32,7 @@
 /* Private macro ------------------------------------------------------------- */
 /* Private variables --------------------------------------------------------- */
 extern __IO uint8_t PrevXferComplete;
+extern __IO uint8_t DebugTransferComplete;
 
 /* Private function prototypes ----------------------------------------------- */
 /* Private functions --------------------------------------------------------- */
@@ -99,3 +100,9 @@ void EP4_IN_Callback (void)
     PrevXferComplete = 1;
     // SwitchSmartcardLED(DISABLE);
 }
+
+void EP5_IN_Callback (void)
+{
+    DebugTransferComplete = 1;
+}
+