RAM usage is to high, will try lib crypto

Makefile

@@ -61,22 +61,22 @@ OPTLEVEL=s
 # Flags
 CFLAGS=-I. $(INC) -g -mmcu=$(MCU) -O$(OPTLEVEL) \
 	-DF_CPU=16500000	                        \
-    -mcall-prologues                            \
-    -mtiny-stack                                \
-    -fno-jump-tables                            \
-    -fno-inline-functions                       \
-    -fno-inline-small-functions                 \
-    -fno-split-wide-types                       \
-	-fpack-struct                               \
-    -fshort-enums                               \
-	-funsigned-bitfields                        \
-    -funsigned-char                             \
-	-Wall -Wstrict-prototypes                   \
-    -Wl,--gc-sections                           \
-    -Wl,--print-gc-sections                     \
-    -ffunction-sections -fdata-sections         \
-	-Wa,-ahlms=$(firstword                      \
-	    $(filter %.lst, $(<:.c=.lst)))
+#    -mcall-prologues                            \
+#    -mtiny-stack                                \
+#    -fno-jump-tables                            \
+#    -fno-inline-functions                       \
+#    -fno-inline-small-functions                 \
+#    -fno-split-wide-types                       \
+#	-fpack-struct                               \
+#    -fshort-enums                               \
+#	-funsigned-bitfields                        \
+#    -funsigned-char                             \
+#	-Wall -Wstrict-prototypes                   \
+#    -Wl,--gc-sections                           \
+#    -Wl,--print-gc-sections                     \
+#    -ffunction-sections -fdata-sections         \
+#	-Wa,-ahlms=$(firstword                      \
+#	    $(filter %.lst, $(<:.c=.lst)))
 ASMFLAGS =-I. $(INC) -mmcu=$(MCU)               \
 	-x assembler-with-cpp                       \
 	-DF_CPU=16500000	                        \
@@ -133,6 +133,6 @@ clean:
 	rm -f *.hex *.elf *.map *.list *.o *~ *.lst
 	rm -f usbdrv/*.o usbdrv/*.map usbdrv/*.list usbdrv/*~ usbdrv/*.lst
 
-test: test.c sha1.c hmac.c
-	gcc test.c sha1.c hmac.c -o test
+test: test.c sha1.c hmac.c trunc.c
+	gcc test.c sha1.c hmac.c trunc.c -o test
 

main.c

@@ -4,6 +4,18 @@
 #define DEBUG
 
 #ifdef DEBUG
+
+#define MYUBRR 8 /*BAUD=115200*/
+
+void initUSART(){
+	UBRR0 = (unsigned char) MYUBRR;
+	
+	/*enable USART write and read*/
+	UCSR0B |= /*(1<<RXCIE)|*/(1<<RXEN0)|(1<<TXEN0);
+	/*odd parity, 1 stop bit, 8bit words*/
+	UCSR0C |= (1<<UPM01)|(1<<UPM00)|(1<<UCSZ01)|(1<<UCSZ00);
+}
+
 void tx( char data ){
   while ( !( UCSR0A & (1<<UDRE0)) );
   UDR0 = data;
@@ -39,15 +51,51 @@ void sendunum(uint32_t num){
 	sendstr( text+leadingzero );
 }
 
+void tx_hex(uint8_t c){
+    if( ((c&0xF0)>>4) <0x0A ){
+        tx('0'+((c&0xF0)>>4) );
+    }else{
+        tx('A'-0x0A+((c&0xF0)>>4));
+    }
+
+    if( (c&0x0F)<0x0A ){
+        tx('0'+(c&0x0F));
+    }else{
+        tx('A'-0x0A+(c&0x0F));
+    }
+}
+
 char rx( void ){
   while ( !(UCSR0A & (1<<RXC0)) );
   return UDR0;
 }
 #endif //DEBUG
 
+#define SECRET  {'J', 'e', 'f', 'e'};
+#define SECLEN  4
+
+#define MSG "what do ya want for nothing?"
+
+
 int main(void) __attribute__((noreturn));
 int __attribute__((OS_main)) main(void) {
-    sendstr("Hello");
+    int8_t i;
+    uint8_t sec[SECLEN]=SECRET;
+
+	initUSART();
+    //sendstr("Hello\n");
+
+    tx('+');
+
+    hmac(MSG,28,sec,4);
+    //get_otp_from_cnt(777, 6, sec, SECLEN); //get a 6 digit one-time-password with counter 777
+    for(i=0; i<20; i++){                                       
+        tx_hex( ((uint8_t*)sha1_digest)[i] );                   
+    }
+    
+    tx('+');
+    tx('\n');
+
     for(;;){
 
 	}

sha1.c

@@ -1,8 +1,7 @@
 /**
   * SHA1 - Secure Hash Algorithm 
   * This code is a direct implementation of the algorithm presented in rfc3174.
-  * No optimizations has been used, although I tried to keep it small in order
-  * to fit on an ATTiny45 (together with VUSB).
+  * No optimizations has been used, although I tried to keep it small in flashsize
   * It is written in assumption that the target architecture is little endian.
   */
 #include "sha1.h"
@@ -19,12 +18,10 @@
 #define K4 0xCA62C1D6
 
 #define _LROT32(x,n) (( (uint32_t)(x) << n ) | ( (uint32_t)(x) >>(32-n) ))  
-#define _W(n) (n>=16 ? _sha1_chunk_e[n-16] : _sha1_chunk[n])
 
-
-uint32_t _sha1_chunk[16];
-static uint8_t chunk_cnt;
-uint32_t _sha1_chunk_e[64]; /*putting this here saves a lot of code space*/
+/*putting this here saves a lot of code space*/
+static uint32_t _sha1_chunk[80] __attribute__ ((section (".noinit"))); 
+static uint8_t chunk_cnt __attribute__ ((section (".noinit"))); 
 
 void sha1_addbyte(uint8_t c){
 	uint8_t* p=(uint8_t*)_sha1_chunk;
@@ -36,8 +33,11 @@ void sha1_addbyte(uint8_t c){
 	if(chunk_cnt==64){
 		/*chunk extension*/
 		uint32_t a,b,c,d,e;
-		for(i=0; i<64; ++i){    
-            _sha1_chunk_e[i]= _LROT32( _W(i+16-3) ^ _W(i+16-8) ^ _W(i+16-14) ^ _W(i+16-16), 1 );  
+		for(i=16; i<80; ++i){    
+            _sha1_chunk[i]= _LROT32( _sha1_chunk[i- 3] ^ 
+                                     _sha1_chunk[i- 8] ^ 
+                                     _sha1_chunk[i-14] ^ 
+                                     _sha1_chunk[i-16], 1 );  
 		}
 		a=sha1_digest[4];
 		b=sha1_digest[3];
@@ -62,7 +62,7 @@ void sha1_addbyte(uint8_t c){
 				k=K4;
 				f=b ^ c ^ d;
 			}
-			temp = e + k + f+_LROT32(a,5)+_W(i);
+			temp = e + k + f+_LROT32(a,5)+_sha1_chunk[i];
 			e = d;
 			d = c;
 			c = _LROT32(b,30);

test.c

@@ -64,5 +64,7 @@ int main(){
     printf("HMAC: %s\n",sha1sum);
     assert(strcmp("effcdf6ae5eb2fa2d27416d5f184df9c259a7c79",sha1sum)==0);      
 
+    printf("OTP: %d\n",get_otp_from_cnt(777, 6, sec2, 4));
+
     
 }

trunc.c

@@ -1,6 +1,13 @@
 
 #include "trunc.h"
 
+int32_t get_otp_from_cnt(uint64_t cnt, uint8_t digits, uint8_t* secret, uint8_t sec_len){
+    uint8_t tmp[8]={((uint8_t*)&cnt)[7],((uint8_t*)&cnt)[6],((uint8_t*)&cnt)[5],((uint8_t*)&cnt)[4],((uint8_t*)&cnt)[3],((uint8_t*)&cnt)[2],((uint8_t*)&cnt)[1],((uint8_t*)&cnt)[0]};
+    /*Step 1 generate HMAC-SHA1*/
+    hmac(tmp,8,secret,sec_len);
+    return get_otp(hmac_result,digits);
+}
+
 int32_t get_otp(uint8_t* hmac, uint8_t digits){
         uint8_t n;
         uint32_t dt;
@@ -8,12 +15,13 @@ int32_t get_otp(uint8_t* hmac, uint8_t digits){
         /*Step 1 generate HMAC-SHA1*/
         /*Step 2 get DT(HMAC)      */
         /*  get the lower 4-bits and treat them as a number n*/
-        /*  DT is the 32bit integer at HMAC[n]+HMAC[n+1]+HMAC[n+2]+HMAC[n+3]*/
-        n=hmac[SHA1_SIZE-1] & 0x0F;
-        dt= (uint32_t)(hmac[n]&0x7F)<<(uint32_t)24 |
-            (uint32_t)(hmac[n+1])<<(uint32_t)16 | 
-            (uint32_t)(hmac[n+2])<<(uint32_t)8  | 
-            (uint32_t)(hmac[n+3]);
+        /*  DT is the 31bit integer at HMAC[n]+HMAC[n+1]+HMAC[n+2]+HMAC[n+3]*/
+        /*  the MSB is ignored */
+        n=hmac[0] & 0x0F;
+        dt= (uint32_t)(hmac[SHA1_SIZE-1-n]&0x7F)<<(uint32_t)24 |
+            (uint32_t)(hmac[SHA1_SIZE-2-n])<<(uint32_t)16 | 
+            (uint32_t)(hmac[SHA1_SIZE-3-n])<<(uint32_t)8  | 
+            (uint32_t)(hmac[SHA1_SIZE-4-n]);
         /*Step 3 return dt mod 10^digits*/
         switch(digits){
                      case 6: return dt % 1000000;
@@ -22,8 +30,4 @@ int32_t get_otp(uint8_t* hmac, uint8_t digits){
         }
 }
 
-int32_t get_otp_from_cnt(uint32_t cnt, uint8_t digits, uint8_t* secret, uint8_t sec_len){
-    cnt=TO_LITTLE_ENDIAN32(cnt);
-    hmac((uint8_t*)(&cnt),8,secret,sec_len);
-    return get_otp(hmac_result,digits);
-}
+

trunc.h

@@ -13,6 +13,6 @@
                                 (x & 0x00000000000000FFul)<<(7*8) 
 
 int32_t get_otp(uint8_t* hmac, uint8_t digits);
-int32_t get_otp_from_cnt(uint32_t cnt, uint8_t digits, uint8_t* secret, uint8_t sec_len);
+int32_t get_otp_from_cnt(uint64_t cnt, uint8_t digits, uint8_t* secret, uint8_t sec_len);
 
 #endif