firmware/main.c

   1 /* Name: main.c
   2  * Project: labortage-2013-badge
   3  * Author: bg (bg@das-labor.org)
   4  * Creation Date: 2013-10-16
   5  * Tabsize: 4
   6  * Copyright: (c) 2008 by OBJECTIVE DEVELOPMENT Software GmbH, (c) Daniel Otte
   7  * License: GNU GPL v3
   8  * This Revision: $Id: main.c 692 2008-11-07 15:07:40Z cs $
   9  */
  10
  11 /*
  12 This example should run on most AVRs with only little changes. No special
  13 hardware resources except INT0 are used. You may have to change usbconfig.h for
  14 different I/O pins for USB. Please note that USB D+ must be the INT0 pin, or
  15 at least be connected to INT0 as well.
  16 */
  17
  18 #define BUTTON_PIN 4
  19
  20 #define SIMPLE_COUNTER 1
  21 #define NO_CHECK 1
  22
  23 #include <stdint.h>
  24 #include <string.h>
  25 #include <stdbool.h>
  26
  27 #include <avr/io.h>
  28 #include <avr/wdt.h>
  29 #include <avr/eeprom.h>
  30 #include <avr/interrupt.h>  /* for sei() */
  31 #include <util/delay.h>     /* for _delay_ms() */
  32
  33 #include <avr/pgmspace.h>   /* required by usbdrv.h */
  34 #include "usbdrv.h"
  35 #include "requests.h"       /* The custom request numbers we use */
  36 #include "hotp.h"
  37 #if !SIMPLE_COUNTER
  38 #include "percnt2.h"
  39 #endif
  40 #include "usb_keyboard_codes.h"
  41
  42 /* ------------------------------------------------------------------------- */
  43 /* ----------------------------- USB interface ----------------------------- */
  44 /* ------------------------------------------------------------------------- */
  45
  46 #define STATE_WAIT 0
  47 #define STATE_SEND_KEY 1
  48 #define STATE_RELEASE_KEY 2
  49 #define STATE_NEXT 3
  50
  51 PROGMEM const char usbHidReportDescriptor[USB_CFG_HID_REPORT_DESCRIPTOR_LENGTH] = {
  52     0x05, 0x01,                    /* USAGE_PAGE (Generic Desktop) */
  53     0x09, 0x06,                    /* USAGE (Keyboard) */
  54     0xa1, 0x01,                    /* COLLECTION (Application) */
  55     0x75, 0x01,                    /*   REPORT_SIZE (1) */
  56     0x95, 0x08,                    /*   REPORT_COUNT (8) */
  57     0x05, 0x07,                    /*   USAGE_PAGE (Keyboard)(Key Codes) */
  58     0x19, 0xe0,                    /*   USAGE_MINIMUM (Keyboard LeftControl)(224) */
  59     0x29, 0xe7,                    /*   USAGE_MAXIMUM (Keyboard Right GUI)(231) */
  60     0x15, 0x00,                    /*   LOGICAL_MINIMUM (0) */
  61     0x25, 0x01,                    /*   LOGICAL_MAXIMUM (1) */
  62     0x81, 0x02,                    /*   INPUT (Data,Var,Abs) ; Modifier byte */
  63     0x95, 0x01,                    /*   REPORT_COUNT (1) */
  64     0x75, 0x08,                    /*   REPORT_SIZE (8) */
  65     0x81, 0x03,                    /*   INPUT (Cnst,Var,Abs) ; Reserved byte */
  66     0x95, 0x05,                    /*   REPORT_COUNT (5) */
  67     0x75, 0x01,                    /*   REPORT_SIZE (1) */
  68     0x05, 0x08,                    /*   USAGE_PAGE (LEDs) */
  69     0x19, 0x01,                    /*   USAGE_MINIMUM (Num Lock) */
  70     0x29, 0x05,                    /*   USAGE_MAXIMUM (Kana) */
  71     0x91, 0x02,                    /*   OUTPUT (Data,Var,Abs) ; LED report */
  72     0x95, 0x01,                    /*   REPORT_COUNT (1) */
  73     0x75, 0x03,                    /*   REPORT_SIZE (3) */
  74     0x91, 0x03,                    /*   OUTPUT (Cnst,Var,Abs) ; LED report padding */
  75     0x95, 0x06,                    /*   REPORT_COUNT (6) */
  76     0x75, 0x08,                    /*   REPORT_SIZE (8) */
  77     0x15, 0x00,                    /*   LOGICAL_MINIMUM (0) */
  78     0x25, 0x65,                    /*   LOGICAL_MAXIMUM (101) */
  79     0x05, 0x07,                    /*   USAGE_PAGE (Keyboard)(Key Codes) */
  80     0x19, 0x00,                    /*   USAGE_MINIMUM (Reserved (no event indicated))(0) */
  81     0x29, 0x65,                    /*   USAGE_MAXIMUM (Keyboard Application)(101) */
  82     0x81, 0x00,                    /*   INPUT (Data,Ary,Abs) */
  83     0xc0                           /* END_COLLECTION */
  84 };
  85
  86 static uint16_t secret_length_ee EEMEM = 0;
  87 static uint8_t  secret_ee[32] EEMEM;
  88 static uint8_t  reset_counter_ee EEMEM = 0;
  89 static uint8_t  digits_ee EEMEM = 8;
  90
  91 #if SIMPLE_COUNTER
  92 static uint32_t counter_ee EEMEM = 0;
  93 #endif
  94
  95 static uint8_t dbg_buffer[8];
  96 static uint8_t secret[32];
  97 static uint16_t secret_length_b;
  98 static char token[10];
  99
 100 #define UNI_BUFFER_SIZE 16
 101
 102 static union __attribute__((packed)) {
 103         uint8_t  w8[UNI_BUFFER_SIZE];
 104         uint16_t w16[UNI_BUFFER_SIZE/2];
 105         uint32_t w32[UNI_BUFFER_SIZE/4];
 106         void*    ptr[UNI_BUFFER_SIZE/sizeof(void*)];
 107 } uni_buffer;
 108
 109 static uint8_t current_command;
 110
 111 typedef struct __attribute__((packed)) {
 112     uint8_t modifier;
 113     uint8_t reserved;
 114     uint8_t keycode[6];
 115 } keyboard_report_t;
 116
 117 static keyboard_report_t keyboard_report; /* report sent to the host */
 118 static uchar idleRate;  /* in 4 ms units */
 119 static uchar key_state = STATE_WAIT;
 120 volatile static uchar LED_state = 0xff;
 121 /* ------------------------------------------------------------------------- */
 122
 123 static
 124 void memory_clean(void) {
 125     memset(secret, 0, 32);
 126     secret_length_b = 0;
 127 }
 128
 129 static
 130 uint8_t secret_set(void){
 131 #if !NO_CHECK
 132     uint8_t r;
 133     union {
 134         uint8_t w8[32];
 135         uint16_t w16[16];
 136     } read_back;
 137 #endif
 138     const uint8_t length_B = (secret_length_b + 7) / 8;
 139
 140     eeprom_busy_wait();
 141     eeprom_write_block(secret, secret_ee, length_B);
 142 #if !NO_CHECK
 143     eeprom_busy_wait();
 144     eeprom_read_block(read_back.w8, secret_ee, length_B);
 145     r = memcmp(secret, read_back.w8, length_B);
 146     memory_clean();
 147     memset(read_back.w8, 0, 32);
 148     if (r) {
 149         return 1;
 150     }
 151 #endif
 152     eeprom_busy_wait();
 153     eeprom_write_word(&secret_length_ee, secret_length_b);
 154 #if !NO_CHECK
 155     eeprom_busy_wait();
 156     r = eeprom_read_word(&secret_length_ee) == secret_length_b;
 157     memory_clean();
 158     *read_back.w16 = 0;
 159     if (!r) {
 160         return 1;
 161     }
 162 #else
 163     memory_clean();
 164 #endif
 165
 166     return 0;
 167 }
 168
 169 static
 170 void counter_inc(void){
 171 #if SIMPLE_COUNTER
 172     uint32_t t;
 173     eeprom_busy_wait();
 174     t = eeprom_read_dword(&counter_ee);
 175     eeprom_busy_wait();
 176     eeprom_write_dword(&counter_ee, t + 1);
 177 #else
 178     percnt_inc(0);
 179 #endif
 180 }
 181
 182 static
 183 void counter_reset(void) {
 184     uint8_t reset_counter;
 185     eeprom_busy_wait();
 186     reset_counter = eeprom_read_byte(&reset_counter_ee);
 187 #if SIMPLE_COUNTER
 188     eeprom_busy_wait();
 189     eeprom_write_dword(&counter_ee, 0);
 190 #else
 191     percnt_reset(0);
 192 #endif
 193     eeprom_busy_wait();
 194     eeprom_write_byte(&reset_counter_ee, reset_counter + 1);
 195 }
 196
 197 static
 198 void counter_init(void) {
 199 #if !SIMPLE_COUNTER
 200     eeprom_busy_wait();
 201     if (eeprom_read_byte(&reset_counter_ee) == 0) {
 202         counter_reset();
 203     }
 204     percnt_init(0);
 205 #endif
 206 }
 207
 208 static
 209 void token_generate(void) {
 210     counter_inc();
 211     eeprom_busy_wait();
 212     eeprom_read_block(secret, secret_ee, 32);
 213     eeprom_busy_wait();
 214 #if SIMPLE_COUNTER
 215     hotp(token, secret, eeprom_read_word(&secret_length_ee), eeprom_read_dword(&counter_ee), eeprom_read_byte(&digits_ee));
 216 #else
 217     hotp(token, secret, eeprom_read_word(&secret_length_ee), percnt_get(0), eeprom_read_byte(&digits_ee));
 218 #endif
 219     memory_clean();
 220 }
 221
 222
 223 static
 224 void buildReport(uchar send_key) {
 225     keyboard_report.modifier = 0;
 226
 227     switch (send_key) {
 228     case '1' ... '9':
 229         keyboard_report.keycode[0] = KEY_1 + (send_key-'1');
 230         break;
 231     case '0':
 232         keyboard_report.keycode[0] = KEY_0;
 233         break;
 234     default:
 235         keyboard_report.keycode[0] = 0;
 236     }
 237 }
 238
 239 static
 240 int8_t button_get_debounced(volatile uint8_t debounce_count) {
 241     uint8_t v;
 242     v = PINB & _BV(BUTTON_PIN);
 243     while (debounce_count-- && v == (PINB & _BV(BUTTON_PIN))) {
 244         ;
 245     }
 246     if (debounce_count) {
 247         return -1;
 248     }
 249     return v ? 0 : 1;
 250 }
 251
 252 usbMsgLen_t usbFunctionSetup(uchar data[8])
 253 {
 254         usbRequest_t    *rq = (usbRequest_t *)data;
 255         if ((rq->bmRequestType & USBRQ_TYPE_MASK) == USBRQ_TYPE_CLASS) {    /* class request type */
 256             switch(rq->bRequest) {
 257         case USBRQ_HID_GET_REPORT: /* send "no keys pressed" if asked here */
 258             /* wValue: ReportType (highbyte), ReportID (lowbyte) */
 259             usbMsgPtr = (void *)&keyboard_report; /* we only have this one */
 260             keyboard_report.modifier = 0;
 261             keyboard_report.keycode[0] = 0;
 262             return sizeof(keyboard_report);
 263         case USBRQ_HID_SET_REPORT: /* if wLength == 1, should be LED state */
 264             if (rq->wLength.word == 1) {
 265                 current_command = LED_WRITE;
 266                 return USB_NO_MSG;
 267             }
 268             return 0;
 269         case USBRQ_HID_GET_IDLE: /* send idle rate to PC as required by spec */
 270             usbMsgPtr = &idleRate;
 271             return 1;
 272         case USBRQ_HID_SET_IDLE: /* save idle rate as required by spec */
 273             idleRate = rq->wValue.bytes[1];
 274             return 0;
 275         }
 276     }
 277     if ((rq->bmRequestType & USBRQ_TYPE_MASK) == USBRQ_TYPE_VENDOR) {
 278                 current_command = rq->bRequest;
 279         usbMsgPtr = uni_buffer.w8;
 280         switch(rq->bRequest)
 281                 {
 282         case CUSTOM_RQ_SET_SECRET:
 283             secret_length_b = rq->wValue.word;
 284             if (secret_length_b > 256) {
 285                 secret_length_b = 256;
 286             }
 287             uni_buffer.w8[0] = 0;
 288             return USB_NO_MSG;
 289         case CUSTOM_RQ_INC_COUNTER:
 290             counter_inc();
 291             return 0;
 292         case CUSTOM_RQ_GET_COUNTER:
 293 #if SIMPLE_COUNTER
 294             eeprom_busy_wait();
 295             uni_buffer.w32[0] = eeprom_read_dword(&counter_ee);
 296 #else
 297             uni_buffer.w32[0] = percnt_get(0);
 298 #endif
 299             return 4;
 300         case CUSTOM_RQ_RESET_COUNTER:
 301             counter_reset();
 302             return 0;
 303         case CUSTOM_RQ_GET_RESET_COUNTER:
 304             eeprom_busy_wait();
 305             uni_buffer.w8[0] = eeprom_read_byte(&reset_counter_ee);
 306             return 1;
 307         case CUSTOM_RQ_SET_DIGITS:
 308             if (rq->wValue.bytes[0] < 6) {
 309                 rq->wValue.bytes[0] = 6;
 310             }
 311             if (rq->wValue.bytes[0] > 9) {
 312                 rq->wValue.bytes[0] = 9;
 313             }
 314             eeprom_busy_wait();
 315             eeprom_write_byte(&digits_ee, rq->wValue.bytes[0]);
 316             return 0;
 317         case CUSTOM_RQ_GET_DIGITS:
 318             eeprom_busy_wait();
 319             uni_buffer.w8[0] = eeprom_read_byte(&digits_ee);
 320             return 1;
 321         case CUSTOM_RQ_GET_TOKEN:
 322             token_generate();
 323             usbMsgPtr = (usbMsgPtr_t)token;
 324             return strlen(token);
 325         case CUSTOM_RQ_PRESS_BUTTON:
 326             key_state = STATE_SEND_KEY;
 327             return 0;
 328         case CUSTOM_RQ_CLR_DBG:
 329             memset(dbg_buffer, 0, sizeof(dbg_buffer));
 330             return 0;
 331                 case CUSTOM_RQ_SET_DBG:
 332                         return USB_NO_MSG;
 333                 case CUSTOM_RQ_GET_DBG:{
 334                         usbMsgLen_t len = 8;
 335                         if(len > rq->wLength.word){
 336                                 len = rq->wLength.word;
 337                         }
 338                         usbMsgPtr = dbg_buffer;
 339                         return len;
 340                 }
 341                 case CUSTOM_RQ_RESET:
 342                         soft_reset((uint8_t)(rq->wValue.word));
 343                         break;
 344                 case CUSTOM_RQ_READ_BUTTON:
 345                         uni_buffer.w8[0] = button_get_debounced(25);
 346                         return 1;
 347                 }
 348     }
 349
 350     return 0;   /* default for not implemented requests: return no data back to host */
 351 }
 352
 353
 354 uchar usbFunctionWrite(uchar *data, uchar len)
 355 {
 356         switch(current_command){
 357
 358         case LED_WRITE:
 359             if (data[0] != LED_state)
 360                 LED_state = data[0];
 361             return 1; /* Data read, not expecting more */
 362         case CUSTOM_RQ_SET_SECRET:
 363         {
 364             if (uni_buffer.w8[0] < (secret_length_b + 7) / 8) {
 365                 memcpy(&secret[uni_buffer.w8[0]], data, len);
 366                 uni_buffer.w8[0] += len;
 367             }
 368             if (uni_buffer.w8[0] >= (secret_length_b + 7) / 8) {
 369                 secret_set();
 370                 return 1;
 371             }
 372             return 0;
 373         }
 374         case CUSTOM_RQ_SET_DBG:
 375                 if(len > sizeof(dbg_buffer)){
 376                         len = sizeof(dbg_buffer);
 377                 }
 378                 memcpy(dbg_buffer, data, len);
 379                 return 1;
 380         default:
 381                 return 1;
 382         }
 383         return 0;
 384 }
 385 uchar usbFunctionRead(uchar *data, uchar len){
 386         return 0;
 387 }
 388
 389 static void calibrateOscillator(void)
 390 {
 391 uchar       step = 128;
 392 uchar       trialValue = 0, optimumValue;
 393 int         x, optimumDev, targetValue = (unsigned)(1499 * (double)F_CPU / 10.5e6 + 0.5);
 394
 395     /* do a binary search: */
 396     do {
 397         OSCCAL = trialValue + step;
 398         x = usbMeasureFrameLength();    /* proportional to current real frequency */
 399         if(x < targetValue)             /* frequency still too low */
 400             trialValue += step;
 401         step >>= 1;
 402     } while(step > 0);
 403     /* We have a precision of +/- 1 for optimum OSCCAL here */
 404     /* now do a neighborhood search for optimum value */
 405     optimumValue = trialValue;
 406     optimumDev = x; /* this is certainly far away from optimum */
 407     for (OSCCAL = trialValue - 1; OSCCAL <= trialValue + 1; OSCCAL++){
 408         x = usbMeasureFrameLength() - targetValue;
 409         if (x < 0)
 410             x = -x;
 411         if (x < optimumDev) {
 412             optimumDev = x;
 413             optimumValue = OSCCAL;
 414         }
 415     }
 416     OSCCAL = optimumValue;
 417 }
 418
 419
 420 void usbEventResetReady(void)
 421 {
 422     cli();  /* usbMeasureFrameLength() counts CPU cycles, so disable interrupts. */
 423     calibrateOscillator();
 424     sei();
 425 }
 426
 427 /* ------------------------------------------------------------------------- */
 428
 429 int main(void)
 430 {
 431         size_t idx = 0;
 432         int8_t i = 0, last_stable_button_state = 0;
 433
 434     wdt_enable(WDTO_1S);
 435     /* Even if you don't use the watchdog, turn it off here. On newer devices,
 436      * the status of the watchdog (on/off, period) is PRESERVED OVER RESET!
 437      */
 438     /* RESET status: all port bits are inputs without pull-up.
 439      * That's the way we need D+ and D-. Therefore we don't need any
 440      * additional hardware initialization.
 441      */
 442
 443     DDRB &= ~_BV(BUTTON_PIN); /* make button pin input */
 444     PORTB |= _BV(BUTTON_PIN); /* turn on pull-up resistor */
 445     counter_init();
 446     usbInit();
 447     usbDeviceDisconnect();  /* enforce re-enumeration, do this while interrupts are disabled! */
 448     while(--i){             /* fake USB disconnect for ~512 ms */
 449         wdt_reset();
 450         _delay_ms(2);
 451     }
 452     usbDeviceConnect();
 453
 454     sei();
 455
 456     for(;;){                /* main event loop */
 457         wdt_reset();
 458         usbPoll();
 459
 460         i = button_get_debounced(25);
 461         if (i != -1) {
 462             if (last_stable_button_state == 0 && i == 1) {
 463                 key_state = STATE_SEND_KEY;
 464             }
 465             last_stable_button_state = i;
 466         }
 467
 468         if(usbInterruptIsReady() && key_state != STATE_WAIT){
 469             switch(key_state) {
 470             case STATE_SEND_KEY:
 471                 buildReport(token[idx]);
 472                 key_state = STATE_RELEASE_KEY; /* release next */
 473                 break;
 474             case STATE_RELEASE_KEY:
 475                 buildReport(0);
 476                 ++idx;
 477                 if (token[idx] == '\0') {
 478                     idx = 0;
 479                     key_state = STATE_WAIT;
 480                 } else {
 481                     key_state = STATE_SEND_KEY;
 482                 }
 483                 break;
 484             default:
 485                 key_state = STATE_WAIT; /* should not happen */
 486             }
 487                         /* start sending */
 488             usbSetInterrupt((void *)&keyboard_report, sizeof(keyboard_report));
 489
 490         }
 491
 492     }
 493     return 0;
 494 }
 495
 496 /* ------------------------------------------------------------------------- */