Made keystroke sending faster

libcrypt/Makefile

@@ -36,7 +36,7 @@ OBJS =  main.o                  \
         usbdrv/oddebug.o        \
         usbdrv/usbdrvasm.o           
 
-INCLUDE = -Isha1 -Ihmac-sha1 -Iusbdrv -Imem_eval -Ibuffer
+INCLUDE = -Isha1 -Ihmac-sha1 -Iusbdrv -Imem_eval -Ibuffer 
 
 #-------------------------------------------------------------------------
 # macros for the tools

libcrypt/README

@@ -4,8 +4,9 @@ What is this thing?
 
 This device is a hash-based-one-time-password (=HOTP, RFC 4226) generator. You
 can use them to make an existing authentication more secure or as a single
-authentication barrier to enter a system. You can easily do both on linux 
-machines using the oath toolkit (http://www.nongnu.org/oath-toolkit/).
+authentication barrier to enter a system (although I wouldn't recoment that).
+You can easily do both on linux machines using the oath toolkit 
+(http://www.nongnu.org/oath-toolkit/).
 
 How does it work?
 -----------------
@@ -18,7 +19,7 @@ sequence usually happens like this:
     3. Confirm the login by pressing the button on the device this will 
        generate an ENTER-keystroke and the internal counter is icremented
        by one.
-    4. Pressing the button again reset the device, and the sequence
+    4. Pressing the button again resets the device, and the sequence
        repeats. Otherwise just unplug it.
 
 How to install the firmware?
@@ -35,12 +36,25 @@ It is recomended to take a secret of length 20 (longer secrets are supported but
 do not provide additional security). This is basically a sha1 digest. I usually
 do the following to generate secrets:
 
-    
+    >head /dev/urandom | sha1sum
+    11d64fc6fcff5f198976b86cc590fb58a04dc422  -
+
+The resulting define would be:
 
-type make. If the compilation runs well, you will end up with some .hex files:
+    SECRET = -DSECLEN=20 -DSECRET="{0x11, 0xd6, 0x4f, 0xc6, 0xfc, 0xff, ...}" 
+
+Once you're done simply type make. If the compilation runs well, you will end 
+up with some .hex files:
     - The main file: hotp.hex (this goes to the flash)
     - The eeprom init: eeprom.hex (this goes to the internal eeprom)
 
+You can upload them by typing "make install". 
+Now configure the server side: Provide the secret you just used, the initial
+counter value is 0 (Remember to keep a working terminal somewhere in case you 
+lock yourself out). After doing this try to login, if it works you should 
+remove the secret from the makefile and also prevent the microcontroller from
+beeing read. Do this by typing "make lock"
+
 Security considerations:
 ------------------------
 

libcrypt/buffer/buffer.h

@@ -2,7 +2,7 @@
 #define _BUFFER_H
 
 #include "../usb_key_codes.h"
-#include <avr/io.h>
+#include <stdint.h>
 
 #define BUFFER_SIZE 10
 

libcrypt/main.c

@@ -17,9 +17,8 @@
 #include <stdlib.h>
 
 uint8_t reportBuffer[2];     /* buffer for HID reports */
-uint8_t idleRate;
 
-static uint8_t kbd_event_state=0;
+static uint8_t next_key=0, prev_key=0xFF;
 
 uint32_t get_cnt(){
 	void* p=(void*)eeprom_read_word(CNTPOS_PTR);
@@ -84,12 +83,13 @@ int main(void){
     #endif //CALLIB
 
     usbDeviceDisconnect();
-    _delay_ms(300); /* mustn't be that exact */
+    /* just leave some time for a disconnect/connect sequence mustn't be that exact */
+    /* TODO only do this if watchdog was activated*/
+    _delay_ms(200); 
     usbDeviceConnect();
 
     wdt_enable(WDTO_500MS);
 
-    writeToBuffer(USB_KEY_NOP);
     writeToBuffer(USB_KEY_NOP);
 
     if( eeprom_read_word(CNTPOS_PTR)==ERROR ){  
@@ -100,24 +100,35 @@ int main(void){
         writeToBuffer(USB_KEY_R);
     }else{
         cnt = get_cnt();
-        buffer_unum(get_otp_from_cnt(cnt,8,sec,SECLEN));
+        buffer_unum(get_otp_from_cnt(792,8,sec,SECLEN));
         //inc_cnt();
     }
 
     usbInit();
     sei();
     for(;;){
-       wdt_reset();
-       usbPoll();
-        /* we can send another key */
+        wdt_reset();
+        usbPoll();
         if(usbInterruptIsReady()){
-            kbd_event_state=!kbd_event_state;
-            if(kbd_event_state && !buff_empty){
-                buildReport(0x00, readBuffer());
+            if(!buff_empty || next_key!=0){
+                if(next_key==0){
+                    next_key=readBuffer();
+                }
+                if(next_key==prev_key){
+                    /*we must send a NOP in between otherwise it will be
+                     interpreted as only one keystroke*/
+                    buildReport(0x00, USB_KEY_NOP);
+                    /*set the prev key to something different*/
+                    prev_key=!next_key;
+                }else{
+                    buildReport(0x00, next_key);
+                    prev_key=next_key;
+                    next_key=0;
+                }
             }else{
-                buildReport(0x00, 0x00);
+                buildReport(0x00, USB_KEY_NOP);
             }
-            usbSetInterrupt(reportBuffer, sizeof(reportBuffer));
+            usbSetInterrupt(reportBuffer, sizeof(reportBuffer));        
         }
     }
     return 0;

libcrypt/usb_callback.c

@@ -6,7 +6,8 @@
 
 extern void buildReport(uint8_t mod,uint8_t key);
 extern uint8_t reportBuffer[2];
-extern uint8_t idleRate;
+
+uint8_t idleRate;
 
 uint8_t	usbFunctionSetup(uint8_t data[8]){
     usbRequest_t    *rq = (void *)data;