--- /dev/null
+/* mqq160-sign.c */
+/*
+ C code for MQQ160-SIGN suitable for 8-bit smart cards
+
+ It is supposed that the private key is "engraved" in
+ the ROM of the smart card - thus it is here stored as
+ predefined const arrays in "MQQ160-SIGN-PrivateKey.h"
+
+ Programmed by
+ Danilo Gligoroski and Rune Jensen and Daniel Otte
+ March 2010.
+
+ Verified by Danilo Gligoroski
+ March 2010.
+
+*/
+
+#include <string.h>
+#include <stdint.h>
+#include <avr/pgmspace.h>
+#include "memxor.h"
+#include "mqq160-sign.h"
+
+#include "cli.h"
+
+static uint8_t mod20_table[32] PROGMEM = {
+ 4, 5, 6, 7, 8, 9, 10, 11,
+ 12, 13, 14, 15, 16, 17, 18, 19,
+ 0, 1, 2, 3, 4, 5, 6, 7,
+ 8, 9, 10, 11, 12, 13, 14, 15,
+};
+
+static void memxor_idx(void* dest, const void* src, uint16_t length, uint8_t dist){
+ while(length--){
+ *((uint8_t*)dest) ^= *((uint8_t*)src);
+ dest = (uint8_t*)dest + 1;
+ src = (uint8_t*)src + dist;
+ }
+}
+/*
+This is just for testing purposes.
+It should be programmed in a more flexible way
+in the MQQ160-SIGN C Library.
+*/
+
+static void mqq_inv_affine_transformation(const uint8_t* input_bytes, uint8_t* result, const mqq160_sign_key_t* key){
+ /* The matrix SInv is given as two permutations of 160 elements. */
+ uint8_t j, byteindex, bitindex, bitindex_d, byteindex_d, rp1, rp5;
+ uint8_t *rp1_ptr, *rp5_ptr;
+ uint8_t h1[20];
+
+
+ /* Initialize H1 and H2 = 0 */
+ memset(h1, 0, 20);
+ memset(result, 0, 20);
+
+ /*
+ Fill H1 with bits of InputBytes accordingly to RP1 permutation
+ and fill H2 with bits of InputBytes accordingly to RP5 permutation
+ */
+ j=160;
+ byteindex_d = 0;
+ bitindex_d = 0x80;
+ rp1_ptr = key->rp1;
+ rp5_ptr = key->rp5;
+ do{
+ rp1 = *rp1_ptr++;
+ rp5 = *rp5_ptr++;
+ byteindex = rp1>>3;
+ bitindex = 0x80 >> (rp1&0x07);
+ if (input_bytes[byteindex] & bitindex){
+ h1[byteindex_d] ^= bitindex_d;
+ }
+
+ byteindex = rp5>>3;
+ bitindex = 0x80 >> (rp5&0x07);
+ if (input_bytes[byteindex] & bitindex){
+ result[byteindex_d] ^= bitindex_d;
+ }
+ bitindex_d >>= 1;
+ if(bitindex_d==0){
+ ++byteindex_d;
+ bitindex_d = 0x80;
+ }
+ }while(--j);
+// cli_putstr_P(PSTR("\r\nDBG (ref): "));
+// cli_hexdump(h1, 20);
+ for (j=0; j<20; j++){
+ result[j] ^= h1[j] ^ h1[pgm_read_byte(j+mod20_table)]
+ ^ h1[pgm_read_byte(8+j+mod20_table)]
+ ^ h1[pgm_read_byte(12+j+mod20_table)];
+ }
+}
+
+static uint16_t MaskShort[8] = {0x8000, 0x4000, 0x2000, 0x1000, 0x0800, 0x0400, 0x0200, 0x0100};
+
+static uint8_t mqq_q(uint8_t i, uint8_t b1, uint8_t b2, const mqq160_sign_key_t* key){
+ uint8_t e[9];
+ uint16_t a[8];
+ uint8_t result, column, row, k;
+ int8_t j;
+ uint16_t temp;
+ uint8_t *tmp_ptr=key->a;
+ if(i&1){
+ memcpy(e, key->cc1, 9);
+ while(b1){
+ if(b1&0x80){
+ memxor_idx((uint8_t*)e, tmp_ptr, 9, 9);
+ }
+ tmp_ptr++;
+ b1 <<= 1;
+ }
+ }else{
+ memcpy(e, key->cc2, 9);
+ while(b1){
+ if(b1&0x80){
+ memxor((uint8_t*)e, tmp_ptr, 9);
+ }
+ tmp_ptr+=9;
+ b1 <<= 1;
+ }
+ }
+ /* So we finished with obtaining e0 .. e7 and e8 */
+
+ /* We XOR e[8] with b2 and that will be initial value to transform in order to solve a linear system of equations */
+ result=b2 ^ e[8];
+
+ /*
+ We can look at the bits of e0 .. e7 as a columns of a given matrix. We want to define 8 variables that have the rows
+ of that matrix. The variables need to be 16-bit because we will put into the upper 8 bits the bits of e0 .. e7,
+ and the bits of the variable result will be the Least Significant Bits of a[0] ... a[7].
+ */
+ for(j=0; j<8; ++j){
+ row = 0;
+ for(k=0; k<8; ++k){
+ row |= (e[k]&0x80)>>(k);
+ e[k]<<=1;
+ }
+ a[j]=(((uint16_t)row)<<8) | (result>>7);
+ result <<= 1;
+ }
+
+ /* Now we finally realize Gausian elimination */
+
+ /* First we apply upper triangular transformation */
+ for(column=0; column<8; column++)
+ {
+ row=column;
+ while ((a[row] & MaskShort[column]) == 0){
+ row++;
+ }
+ if(row>column)
+ {
+ temp=a[column];
+ a[column]=a[row];
+ a[row]=temp;
+ }
+ for (j=column+1; j<8; j++)
+ if ((a[j]&MaskShort[column]) !=0){
+ a[j] ^= a[column];
+ }
+ }
+
+ /* Then we eliminate 1s above the main diagonal */
+ for (column=7; column>0; column--){
+ for (j=column-1; j>=0; j--){
+ if ((a[j]&MaskShort[column]) !=0){
+ a[j] ^= a[column];
+ }
+ }
+ }
+ /* The result is in the Least Significant Bits of a[0] ... a[7] */
+ result = 0;
+ for(j=0; j<8; ++j){
+ result <<=1;
+ result |= a[j]&1;
+ }
+ return(result);
+}
+
+void mqq160_sign(void* dest, const void* hash, const mqq160_sign_key_t* key){
+ uint8_t i, r1[20], byteindex;
+ mqq_inv_affine_transformation((uint8_t*)hash, (uint8_t*)dest, key);
+ r1[0]=((uint8_t*)dest)[0];
+ for(i=1; i<20; ++i){
+ r1[i] = mqq_q(i, r1[i-1], ((uint8_t*)dest)[i], key);
+ }
+ /*
+ Affine transformation is just for the second call. The constant is extracted
+ from the 4 LSBs of the first 40 bytes of RP5[] and xor-ed to input_bytes[].
+ */
+ byteindex = 0;
+ for (i=0; i<20; i++){
+ r1[i] ^= (uint8_t)((key->rp5[byteindex])<<4)
+ | (uint8_t)(key->rp5[byteindex+1]&0x0F);
+ byteindex += 2;
+ }
+ mqq_inv_affine_transformation(r1, (uint8_t*)dest, key);
+}
projects / avr-crypto-lib.git / blobdiff