diff --git a/source/keys/AES128.c b/source/keys/AES128.c new file mode 100644 index 0000000..36815ac --- /dev/null +++ b/source/keys/AES128.c @@ -0,0 +1,434 @@ +/* ============================================================================================================ * + 2012036901 - 윤진한 + 주 의 사 항 + + + 1. 주석으로 표현된 구현 블록 0에서 12번까지 구현하여 128비트 AES 암호화 알고리즘을 구현해야 함 + 2. AES128(...) 함수의 호출과 리턴이 여러번 반복되더라도 메모리 누수가 생기지 않게 함 + 3. AddRoundKey 함수를 구현할 때에도 파라미터 rKey는 사전에 선언된 지역 배열을 가리키도록 해야 함 + (정확한 구현을 위해서는 포인터 개념의 이해가 필요함) + 4. 배열의 인덱스 계산시 아래에 정의된 KEY_SIZE, ROUNDKEY_SIZE, BLOCK_SIZE를 이용해야 함 + (상수 그대로 사용하면 안됨. 예로, 4, 16는 안되고 KEY_SIZE/4, BLOCK_SIZE로 사용해야 함) + + * ============================================================================================================ */ + +#include +#include +#include "AES128.h" + +#define KEY_SIZE 16 +#define ROUNDKEY_SIZE 176 +#define BLOCK_SIZE 16 + + +/*********************************************** { 구현 0 시작 } ********************************************/ +static const uint8_t ori_sbox[256] = { + 0x63, 0x7C, 0x77, 0x7B, 0xF2, 0x6B, 0x6F, 0xC5, 0x30, 0x01, 0x67, 0x2B, 0xFE, 0xD7, 0xAB, 0x76, + 0xCA, 0x82, 0xC9, 0x7D, 0xFA, 0x59, 0x47, 0xF0, 0xAD, 0xD4, 0xA2, 0xAF, 0x9C, 0xA4, 0x72, 0xC0, + 0xB7, 0xFD, 0x93, 0x26, 0x36, 0x3F, 0xF7, 0xCC, 0x34, 0xA5, 0xE5, 0xF1, 0x71, 0xD8, 0x31, 0x15, + 0x04, 0xC7, 0x23, 0xC3, 0x18, 0x96, 0x05, 0x9A, 0x07, 0x12, 0x80, 0xE2, 0xEB, 0x27, 0xB2, 0x75, + 0x09, 0x83, 0x2C, 0x1A, 0x1B, 0x6E, 0x5A, 0xA0, 0x52, 0x3B, 0xD6, 0xB3, 0x29, 0xE3, 0x2F, 0x84, + 0x53, 0xD1, 0x00, 0xED, 0x20, 0xFC, 0xB1, 0x5B, 0x6A, 0xCB, 0xBE, 0x39, 0x4A, 0x4C, 0x58, 0xCF, + 0xD0, 0xEF, 0xAA, 0xFB, 0x43, 0x4D, 0x33, 0x85, 0x45, 0xF9, 0x02, 0x7F, 0x50, 0x3C, 0x9F, 0xA8, + 0x51, 0xA3, 0x40, 0x8F, 0x92, 0x9D, 0x38, 0xF5, 0xBC, 0xB6, 0xDA, 0x21, 0x10, 0xFF, 0xF3, 0xD2, + 0xCD, 0x0C, 0x13, 0xEC, 0x5F, 0x97, 0x44, 0x17, 0xC4, 0xA7, 0x7E, 0x3D, 0x64, 0x5D, 0x19, 0x73, + 0x60, 0x81, 0x4F, 0xDC, 0x22, 0x2A, 0x90, 0x88, 0x46, 0xEE, 0xB8, 0x14, 0xDE, 0x5E, 0x0B, 0xDB, + 0xE0, 0x32, 0x3A, 0x0A, 0x49, 0x06, 0x24, 0x5C, 0xC2, 0xD3, 0xAC, 0x62, 0x91, 0x95, 0xE4, 0x79, + 0xE7, 0xC8, 0x37, 0x6D, 0x8D, 0xD5, 0x4E, 0xA9, 0x6C, 0x56, 0xF4, 0xEA, 0x65, 0x7A, 0xAE, 0x08, + 0xBA, 0x78, 0x25, 0x2E, 0x1C, 0xA6, 0xB4, 0xC6, 0xE8, 0xDD, 0x74, 0x1F, 0x4B, 0xBD, 0x8B, 0x8A, + 0x70, 0x3E, 0xB5, 0x66, 0x48, 0x03, 0xF6, 0x0E, 0x61, 0x35, 0x57, 0xB9, 0x86, 0xC1, 0x1D, 0x9E, + 0xE1, 0xF8, 0x98, 0x11, 0x69, 0xD9, 0x8E, 0x94, 0x9B, 0x1E, 0x87, 0xE9, 0xCE, 0x55, 0x28, 0xDF, + 0x8C, 0xA1, 0x89, 0x0D, 0xBF, 0xE6, 0x42, 0x68, 0x41, 0x99, 0x2D, 0x0F, 0xB0, 0x54, 0xBB, 0x16 }; + +static const uint8_t inv_sbox[256] = { + 0x52, 0x09, 0x6A, 0xD5, 0x30, 0x36, 0xA5, 0x38, 0xBF, 0x40, 0xA3, 0x9E, 0x81, 0xF3, 0xD7, 0xFB, + 0x7C, 0xE3, 0x39, 0x82, 0x9B, 0x2F, 0xFF, 0x87, 0x34, 0x8E, 0x43, 0x44, 0xC4, 0xDE, 0xE9, 0xCB, + 0x54, 0x7B, 0x94, 0x32, 0xA6, 0xC2, 0x23, 0x3D, 0xEE, 0x4C, 0x95, 0x0B, 0x42, 0xFA, 0xC3, 0x4E, + 0x08, 0x2E, 0xA1, 0x66, 0x28, 0xD9, 0x24, 0xB2, 0x76, 0x5B, 0xA2, 0x49, 0x6D, 0x8B, 0xD1, 0x25, + 0x72, 0xF8, 0xF6, 0x64, 0x86, 0x68, 0x98, 0x16, 0xD4, 0xA4, 0x5C, 0xCC, 0x5D, 0x65, 0xB6, 0x92, + 0x6C, 0x70, 0x48, 0x50, 0xFD, 0xED, 0xB9, 0xDA, 0x5E, 0x15, 0x46, 0x57, 0xA7, 0x8D, 0x9D, 0x84, + 0x90, 0xD8, 0xAB, 0x00, 0x8C, 0xBC, 0xD3, 0x0A, 0xF7, 0xE4, 0x58, 0x05, 0xB8, 0xB3, 0x45, 0x06, + 0xD0, 0x2C, 0x1E, 0x8F, 0xCA, 0x3F, 0x0F, 0x02, 0xC1, 0xAF, 0xBD, 0x03, 0x01, 0x13, 0x8A, 0x6B, + 0x3A, 0x91, 0x11, 0x41, 0x4F, 0x67, 0xDC, 0xEA, 0x97, 0xF2, 0xCF, 0xCE, 0xF0, 0xB4, 0xE6, 0x73, + 0x96, 0xAC, 0x74, 0x22, 0xE7, 0xAD, 0x35, 0x85, 0xE2, 0xF9, 0x37, 0xE8, 0x1C, 0x75, 0xDF, 0x6E, + 0x47, 0xF1, 0x1A, 0x71, 0x1D, 0x29, 0xC5, 0x89, 0x6F, 0xB7, 0x62, 0x0E, 0xAA, 0x18, 0xBE, 0x1B, + 0xFC, 0x56, 0x3E, 0x4B, 0xC6, 0xD2, 0x79, 0x20, 0x9A, 0xDB, 0xC0, 0xFE, 0x78, 0xCD, 0x5A, 0xF4, + 0x1F, 0xDD, 0xA8, 0x33, 0x88, 0x07, 0xC7, 0x31, 0xB1, 0x12, 0x10, 0x59, 0x27, 0x80, 0xEC, 0x5F, + 0x60, 0x51, 0x7F, 0xA9, 0x19, 0xB5, 0x4A, 0x0D, 0x2D, 0xE5, 0x7A, 0x9F, 0x93, 0xC9, 0x9C, 0xEF, + 0xA0, 0xE0, 0x3B, 0x4D, 0xAE, 0x2A, 0xF5, 0xB0, 0xC8, 0xEB, 0xBB, 0x3C, 0x83, 0x53, 0x99, 0x61, + 0x17, 0x2B, 0x04, 0x7E, 0xBA, 0x77, 0xD6, 0x26, 0xE1, 0x69, 0x14, 0x63, 0x55, 0x21, 0x0C, 0x7D }; + +static const uint8_t rcon[256] = { + 0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a, + 0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3, 0x7d, 0xfa, 0xef, 0xc5, 0x91, 0x39, + 0x72, 0xe4, 0xd3, 0xbd, 0x61, 0xc2, 0x9f, 0x25, 0x4a, 0x94, 0x33, 0x66, 0xcc, 0x83, 0x1d, 0x3a, + 0x74, 0xe8, 0xcb, 0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8, + 0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3, 0x7d, 0xfa, 0xef, + 0xc5, 0x91, 0x39, 0x72, 0xe4, 0xd3, 0xbd, 0x61, 0xc2, 0x9f, 0x25, 0x4a, 0x94, 0x33, 0x66, 0xcc, + 0x83, 0x1d, 0x3a, 0x74, 0xe8, 0xcb, 0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, + 0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3, + 0x7d, 0xfa, 0xef, 0xc5, 0x91, 0x39, 0x72, 0xe4, 0xd3, 0xbd, 0x61, 0xc2, 0x9f, 0x25, 0x4a, 0x94, + 0x33, 0x66, 0xcc, 0x83, 0x1d, 0x3a, 0x74, 0xe8, 0xcb, 0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, + 0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35, + 0x6a, 0xd4, 0xb3, 0x7d, 0xfa, 0xef, 0xc5, 0x91, 0x39, 0x72, 0xe4, 0xd3, 0xbd, 0x61, 0xc2, 0x9f, + 0x25, 0x4a, 0x94, 0x33, 0x66, 0xcc, 0x83, 0x1d, 0x3a, 0x74, 0xe8, 0xcb, 0x8d, 0x01, 0x02, 0x04, + 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63, + 0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3, 0x7d, 0xfa, 0xef, 0xc5, 0x91, 0x39, 0x72, 0xe4, 0xd3, 0xbd, + 0x61, 0xc2, 0x9f, 0x25, 0x4a, 0x94, 0x33, 0x66, 0xcc, 0x83, 0x1d, 0x3a, 0x74, 0xe8, 0xcb, 0x8d }; + +static const uint8_t matrix[16] = { + 0x02, 0x03, 0x01, 0x01, + 0x01, 0x02, 0x03, 0x01, + 0x01, 0x01, 0x02, 0x03, + 0x03, 0x01, 0x01, 0x02 }; + +static const uint8_t inv_matrix[16] = { + 0x0E, 0x0B, 0x0D, 0x09, + 0x09, 0x0E, 0x0B, 0x0D, + 0x0D, 0x09, 0x0E, 0x0B, + 0x0B, 0x0D, 0x09, 0x0E }; + +// Additional Fuction - Galois field mutiplication. +BYTE GF_Mutiplication(uint8_t num,BYTE data){ + int i; + BYTE tmp = 0; + BYTE mask = 0x01; + + for (i = 0;i < num;i ++){ + if (num & mask){ + tmp ^= data; + } + if (data & 0x80){ + data = (data << 1) ^ 0x1b; + } else { + data <<= 1; + } + mask <<= 1; + } + return tmp; +}// Galois field mutiplication function. + +/*********************************************** { 구현 0 종료 } ********************************************/ + + +/* <키스케줄링 함수> + * + * key 키스케줄링을 수행할 16바이트 키 + * roundKey 키스케줄링의 결과인 176바이트 라운드키가 담길 공간 + */ +void expandKey(BYTE *key, BYTE *roundKey){ + + /*********************************************** { 구현 1 시작 } ********************************************/ + int i,j,k,roundKey_filled = 0; + BYTE tmp,gkey[4],tmp_key[4][4]; + + for (i = 0;i < KEY_SIZE/4;i ++){ + for (j = 0;j < KEY_SIZE/4;j ++){ + tmp_key[i][j] = *(key + i*4 + j); + *(roundKey + (roundKey_filled++)) = tmp_key[i][j]; + } + }// The first round key is the original key itself. + for (i = 1;i < ROUNDKEY_SIZE/KEY_SIZE;i ++){ + for (j = 0;j < KEY_SIZE/4 ;j ++){ + gkey[j] = tmp_key[3][j]; + } + tmp = gkey[0]; + for (j = 0;j < KEY_SIZE/4 - 1 ;j ++){ + gkey[j] = gkey[j + 1]; + } + gkey[KEY_SIZE/4 - 1] = tmp; + // Shift left 1 bit. + for (j = 0;j < KEY_SIZE/4 ;j ++){ + gkey[j] = ori_sbox[ gkey[j] ]; + }// Sub ori_sbox. + gkey[0] ^= rcon[i]; + // XOR with rcon matrix. + for (j = 0;j < KEY_SIZE/4 ;j ++){ + tmp_key[0][j] ^= gkey[j]; + }// XOR gkey. + for (j = 1;j < KEY_SIZE/4 ;j ++){ + for (k = 0;k < KEY_SIZE/4 ;k ++){ + tmp_key[j][k] ^= tmp_key[j-1][k]; + } + }// Make round key. + for (j = 0;j < KEY_SIZE/4 ;j ++){ + for (k = 0;k < KEY_SIZE/4 ;k ++){ + *(roundKey + (roundKey_filled++)) = tmp_key[j][k]; + } + }// Insert calculated key into RoundKey. + } + /*********************************************** { 구현 1 종료 } ********************************************/ + +} + + +/* + * + * block SubBytes 수행할 16바이트 블록. 수행 결과는 해당 배열에 바로 반영 + * mode SubBytes 수행 모드 + */ +BYTE* subBytes(BYTE *block, int mode){ + + /* 필요하다 생각하면 추가 선언 */ + int i; + + switch(mode){ + + case ENC: + /*********************************************** { 구현 2 시작 } ********************************************/ + for (i = 0;i < BLOCK_SIZE;i ++){ + *(block + i) = ori_sbox[ *(block + i) ]; + }// SubByte ori_sbox. + /*********************************************** { 구현 2 종료 } ********************************************/ + break; + + case DEC: + /*********************************************** { 구현 3 시작 } ********************************************/ + for (i = 0;i < BLOCK_SIZE;i ++){ + *(block + i) = inv_sbox[ *(block + i) ]; + }// SubByte inv_sbox. + /*********************************************** { 구현 3 종료 } ********************************************/ + break; + + default: + fprintf(stderr, "Invalid mode!\n"); + exit(1); + } + + return block; +} + + +/* + * + * block ShiftRows 수행할 16바이트 블록. 수행 결과는 해당 배열에 바로 반영 + * mode ShiftRows 수행 모드 + */ +BYTE* shiftRows(BYTE *block, int mode){ + + /* 필요하다 생각하면 추가 선언 */ + int i,j,rep; + BYTE tmp; + + switch(mode){ + + case ENC: + /*********************************************** { 구현 4 시작 } ********************************************/ + for (i = 1; i < BLOCK_SIZE/4;i ++){ + for (rep = i;rep >= 1;rep --){ + tmp = *(block + i); + for (j = i; j < (i + BLOCK_SIZE - BLOCK_SIZE/4) ;j += 4){ + *(block + j) = *(block + j + BLOCK_SIZE/4); + } + *(block + i + BLOCK_SIZE - BLOCK_SIZE/4) = tmp; + } + } + // 1 left Shift 2nd Col, 2 left Shift 3rd Col, 3 left Shift 4th Col. + /*********************************************** { 구현 4 종료 } ********************************************/ + break; + + case DEC: + /*********************************************** { 구현 5 시작 } ********************************************/ + for (i = 1; i < BLOCK_SIZE/4;i ++){ + for (rep = i;rep >= 1;rep --){ + tmp = *(block + i + BLOCK_SIZE - BLOCK_SIZE/4); + for (j = i + BLOCK_SIZE - BLOCK_SIZE/4; j >= i ;j -= 4){ + *(block + j) = *(block + j - BLOCK_SIZE/4); + } + *(block + i) = tmp; + } + } + // 1 right Shift 2nd Col, 2 right Shift 3rd Col, 3 right Shift 4th Col. + /*********************************************** { 구현 5 종료 } ********************************************/ + break; + + default: + fprintf(stderr, "Invalid mode!\n"); + exit(1); + } + + return block; +} + +/* + * + * block MixColumns을 수행할 16바이트 블록. 수행 결과는 해당 배열에 바로 반영 + * mode MixColumns의 수행 모드 + */ +BYTE* mixColumns(BYTE *block, int mode){ + + /* 필요하다 생각하면 추가 선언 */ + int i,j,k; + + BYTE tmp[16] = {0,}; + BYTE tmp2[4][4]; + + for (i=0;i<4;i++){ for (j=0;j<4;j++){ tmp2[i][j] = *(block+i*4+j); } } + for (i=0;i<4;i++){ for (j=0;j<4;j++){ *(block+i*4+j) = tmp2[j][i]; } } + + switch(mode){ + + case ENC: + /*********************************************** { 구현 6 시작 } ********************************************/ + for (i = 0;i < BLOCK_SIZE/4 ;i ++){ + for (j = 0;j < BLOCK_SIZE/4 ;j ++){ + for (k = 0;k < BLOCK_SIZE/4 ;k ++){ + tmp[ i*4 +j ] ^= GF_Mutiplication(matrix[ i*4 + k ],*(block + k*4 + j)); + } + } + }// Galois field mutiplication data with matirx. + /*********************************************** { 구현 6 종료 } ********************************************/ + break; + + case DEC: + /*********************************************** { 구현 7 시작 } ********************************************/ + for (i = 0;i < BLOCK_SIZE/4 ;i ++){ + for (j = 0;j < BLOCK_SIZE/4 ;j ++){ + for (k = 0;k < BLOCK_SIZE/4 ;k ++){ + tmp[ i*4 +j ] ^= GF_Mutiplication(inv_matrix[ i*4 + k],*(block + k*4 + j)); + } + } + }// Galois field mutiplication data with inv_matirx. + /*********************************************** { 구현 7 종료 } ********************************************/ + break; + + default: + fprintf(stderr, "Invalid mode!\n"); + exit(1); + } + + for (i=0;i<4;i++){ for (j=0;j<4;j++){ tmp2[i][j] = tmp[i*4+j]; } } + for (i = 0;i + * + * block AddRoundKey를 수행할 16바이트 블록. 수행 결과는 해당 배열에 반영 + * rKey AddRoundKey를 수행할 16바이트 라운드키 + */ +BYTE* addRoundKey(BYTE *block, BYTE *rKey){ + + /*********************************************** { 구현 8 시작 } ********************************************/ + int i,j; + for (i = 0 ; i < BLOCK_SIZE/4 ; i++){ + for (j = i ; j < BLOCK_SIZE ; j+=4){ + *(block + j) ^= *(rKey + j); + } + }// XOR Calculate origin block data with RoundKey. + /*********************************************** { 구현 8 종료 } ********************************************/ + + return block; +} + + +/* <128비트 AES 암호화 함수> + * + * plain 바이트 배열로 구성된 평문 (16바이트 고정) + * key 128비트 암호키 (16바이트) + * + * @ret 암호화된 암호문 + */ +BYTE* encrypt(BYTE *plain, BYTE *key){ + BYTE roundKey[ROUNDKEY_SIZE]; + + /*********************************************** { 구현 9 시작 } ********************************************/ + int round; + + for (round = 0; round <= 10; round ++){ + if (round == 0){ // initial round of encryption. + expandKey(key,roundKey); + addRoundKey(plain,roundKey); + } else if (round == 10){ // final round of encryption. + subBytes(plain,ENC); + shiftRows(plain,ENC); + addRoundKey(plain,roundKey + round*KEY_SIZE); + } else { // 9 main rounds of encryption. + subBytes(plain,ENC); + shiftRows(plain,ENC); + mixColumns(plain,ENC); + addRoundKey(plain,roundKey + round*KEY_SIZE); + } + } + return plain; + /*********************************************** { 구현 9 종료 } ********************************************/ +} + + +/* <128비트 AES 복호화 함수> + * + * cipher 바이트 배열로 구성된 평문 (16바이트 고정) + * key 128비트 암호키 (16바이트) + * + * @ret 복호화된 평문 + */ +BYTE* decrypt(BYTE *cipher, BYTE *key){ + BYTE roundKey[ROUNDKEY_SIZE]; + + /*********************************************** { 구현 10 시작 } ********************************************/ + int round; + + for (round = 10; round >=0; round --){ + if (round == 0){ // final round of encryption. + shiftRows(cipher,DEC); + subBytes(cipher,DEC); + addRoundKey(cipher,roundKey); + } else if (round == 10){ // initial round of encryption. + expandKey(key,roundKey); + addRoundKey(cipher,roundKey + round*KEY_SIZE); + } else { // 9 main rounds of encryption. + shiftRows(cipher,DEC); + subBytes(cipher,DEC); + addRoundKey(cipher,roundKey + round*KEY_SIZE); + mixColumns(cipher,DEC); + } + } + return cipher; + /*********************************************** { 구현 10 종료 } ********************************************/ +} + + +/* <128비트 AES 암복호화 함수> + * + * mode가 ENC일 경우 평문을 암호화하고, DEC일 경우 암호문을 복호화하는 함수 + * + * [ENC 모드] + * plain 평문 바이트 배열 + * cipher 결과(암호문)이 담길 바이트 배열. 호출하는 사용자가 사전에 메모리를 할당하여 파라미터로 넘김 + * key 128비트 암호키 (16바이트) + * + * [DEC 모드] + * plain 결과(평문)가 담길 바이트 배열. 호출하는 사용자가 사전에 메모리를 할당하여 파라미터로 넘김 + * cipher 암호문 바이트 배열 + * key 128비트 암호키 (16바이트) + */ +void AES128(BYTE *plain, BYTE *cipher, BYTE *key, int mode){ + BYTE *tmp; + + if(mode == ENC){ + tmp = encrypt(plain, key); + + /*********************************************** { 구현 11 시작 } ********************************************/ + for (int i = 0; i < BLOCK_SIZE ; i ++){ + *(cipher + i) = *(tmp + i); + }// copy tmp blocks to ciper blocks. + /*********************************************** { 구현 11 종료 } ********************************************/ + + }else if(mode == DEC){ + tmp = decrypt(cipher, key); + + /*********************************************** { 구현 12 시작 } ********************************************/ + for (int i = 0; i < BLOCK_SIZE ; i ++){ + *(plain + i) = *(tmp + i); + }// copy tmp blocks to plain blocks. + /*********************************************** { 구현 12 종료 } ********************************************/ + }else{ + fprintf(stderr, "Invalid mode!\n"); + exit(1); + } +} diff --git a/source/keys/AES128.h b/source/keys/AES128.h new file mode 100644 index 0000000..45d7902 --- /dev/null +++ b/source/keys/AES128.h @@ -0,0 +1,10 @@ + +// 암호화 모드 +#define ENC 1 +// 복호화 모드 +#define DEC 0 + +typedef unsigned char BYTE; + +// 128비트 AES 암복호화 인터페이스 +void AES128(BYTE *plain, BYTE *cipher, BYTE *key, int mode); \ No newline at end of file diff --git a/source/keys/XTS_AES.c b/source/keys/XTS_AES.c new file mode 100644 index 0000000..9501f6b --- /dev/null +++ b/source/keys/XTS_AES.c @@ -0,0 +1,171 @@ +/* ============================================================================================================ * + 2012036901 - 윤진한 + 주 의 사 항 + + + 1. 주석으로 표현된 구현 블록 13에서 14번까지 구현하여 128비트 AES 암호화 알고리즘을 구현해야 함 + 2. AES.c를 먼저 구현한 다음, 해당 파일을 구현함 + 3. 사전에 주어진 메뉴얼 속 수도코드를 참고하여 구현함 + 4. 구현은 다양한 방식으로 이뤄질 수 있음 + 5. AES.h에 정의된 AES128(...) 함수만을 이용해서 구현해야 함 + 6. XTS_AES128(...) 함수의 호출과 리턴이 여러번 반복되더라도 메모리 누수가 생기지 않게 함 + + * ============================================================================================================ */ + +#include +#include +#include "XTS_AES.h" +#include "AES128.h" + +/*********************************************** { 구현 13 시작 } ********************************************/ +#define KEY_SIZE 16 +#define BLOCK_SIZE 16 +extern uint8_t iv[]; +uint8_t iv2[BLOCK_SIZE]; + +// Additional Generator function in GF(2^128) to make tweakable variable. +void GF_Mutiplication_xts(uint8_t *T){ + + uint32_t x; + uint8_t t, tt; + + for (x = t = 0;x < BLOCK_SIZE;x ++) { + tt = *(T + x) >> 7; + *(T + x) = ((*(T + x) << 1) | t) & 0xFF; + t = tt; + } + if (tt) { + *(T) ^= 0x87; + } +} +// Generator function in GF(2^128). +/*********************************************** { 구현 13 종료 } ********************************************/ + + +/* <128비트 XTS_AES 암복호화 함수> + * + * mode가 ENC일 경우 평문을 암호화하고, DEC일 경우 암호문을 복호화하는 함수 + * + * [ENC 모드] + * plain 평문 바이트 배열 + * cipher 결과(암호문)이 담길 바이트 배열. 호출하는 사용자가 사전에 메모리를 할당하여 파라미터로 넘김 + * size 평문 크기 (바이트 단위) + * key 256비트 암호키 (32바이트). 상위 16바이트는 key1, 하위 16바이트는 key2 + * + * [DEC 모드] + * plain 결과(평문)가 담길 바이트 배열. 호출하는 사용자가 사전에 메모리를 할당하여 파라미터로 넘김 + * cipher 암호문 바이트 배열 + * size 암호문 크기 (바이트 단위) + * key 256비트 암호키 (32바이트). 상위 16바이트는 key1, 하위 16바이트는 key2 + */ +void XTS_AES128(BYTE *plain, BYTE *cipher, unsigned int size, BYTE* key, int mode){ + + /*********************************************** { 구현 14 시작 } ********************************************/ + int i,j,tmp = 0; + BYTE *T = (BYTE *)malloc(sizeof(BYTE)*BLOCK_SIZE); + BYTE *T2 = (BYTE *)malloc(sizeof(BYTE)*BLOCK_SIZE); + BYTE *PP = (BYTE *)malloc(sizeof(BYTE)*BLOCK_SIZE); + BYTE *CC = (BYTE *)malloc(sizeof(BYTE)*BLOCK_SIZE); + + for (i = 0;i < BLOCK_SIZE;i ++){ + *(iv2 + i) = *(iv + i); + } // copy initial vector to use ENC / DEC. + + AES128(iv2,T,key + KEY_SIZE,ENC); + // create initial T with iv. ( ∂(0) == E(key2)(iv,T) ) + + if(mode == ENC){ + + for (i = 0;i < size/BLOCK_SIZE;i ++){ + + for (j = 0;j < BLOCK_SIZE;j ++){ + *(PP + j) = plain[ i*BLOCK_SIZE + j ] ^ *(T + j); + }// create PP blocks. + AES128(PP,CC,key,ENC); + // create CC blocks. + for (j = 0;j < BLOCK_SIZE;j ++){ + cipher[ i*BLOCK_SIZE + j ] = *(CC + j) ^ *(T + j); + }// create ciper blocks. + GF_Mutiplication_xts(T); + // create tweakable block. + }// when plain text is 16 multiples, it's over. + + if (size%BLOCK_SIZE != 0){ + // cipertext stealing. + + for (j = 0;j < (size%BLOCK_SIZE);j ++){ + cipher[ i*BLOCK_SIZE + j ] = cipher[ (i-1)*16 + j ]; + *(PP + j) = *(T + j) ^ plain[ i*BLOCK_SIZE + j ]; + }// shift and XOR. + for (j = size%BLOCK_SIZE;j < BLOCK_SIZE;j ++){ + *(PP + j) = *(T + j) ^ cipher[ (i-1)*BLOCK_SIZE + j ]; + }// create Additional PP blocks. + AES128(PP,CC,key,ENC); + // create Additional CC blocks. + for (j = 0;j < BLOCK_SIZE;j ++){ + cipher[ (i-1)*BLOCK_SIZE + j ] = *(T + j) ^ *(CC + j); + }// create Additional ciper blocks. + + }// when plain text length is not 16 multiples, it's done. + + }else if(mode == DEC){ + + int check = (size%BLOCK_SIZE==0) ? 0 : 1; + // judge variable that size%BLOCK_SIZE is 0 or is not 0. + // check == 0 is size%BLOCK_SIZE == 0. + // check == 1 is size%BLOCK_SIZE != 0. + for (i = 0;i < size/BLOCK_SIZE;i ++){ + + if (i == size/BLOCK_SIZE - 1 && check) { + tmp = size/BLOCK_SIZE - 1; + break; + } + // when ciper text length is not 16 multiples. + for (j = 0;j < BLOCK_SIZE;j ++){ + *(CC + j) = cipher[ i*BLOCK_SIZE + j ] ^ *(T + j); + }// create PP blocks. + AES128(PP,CC,key,DEC); + // create CC blocks. + for (j = 0;j < BLOCK_SIZE;j ++){ + plain[ i*BLOCK_SIZE + j ] = *(PP + j) ^ *(T + j); + }// create plain blocks. + GF_Mutiplication_xts(T); + // create tweakable block. + } + + if (check) { + // when ciper text length is not 16 multiples. + // cipertext stealing. + for (j = 0;j < BLOCK_SIZE;j ++){ + *(T2 + j) = *(T + j); + }// copy tweakable block to tmp array. + GF_Mutiplication_xts(T); + // create tweakable block. + for (j = 0;j < BLOCK_SIZE;j ++){ + *(CC + j) = *(T + j) ^ cipher[ tmp*BLOCK_SIZE + j ]; + }// create Additional ciper blocks. + AES128(PP,CC,key,DEC); + // create CC blocks. + for (j = 0;j < size%BLOCK_SIZE;j ++){ + plain[ (tmp + 1)*BLOCK_SIZE + j ] = *(T + j) ^ *(PP + j); + *(CC + j) = *(T2 + j) ^ cipher[ (tmp + 1)*BLOCK_SIZE + j ]; + }// shift and XOR. + for (j = size%BLOCK_SIZE;j < BLOCK_SIZE;j ++){ + *(CC + j) = *(T2 + j) ^ *(T + j) ^ *(PP + j); + }// create Additional ciper blocks. + AES128(PP,CC,key,DEC); + for (j = 0;j < BLOCK_SIZE;j ++){ + plain[ tmp*BLOCK_SIZE + j ] = *(T2 + j) ^ *(PP + j); + }// create Additional PP blocks. + } + + }else{ + fprintf(stderr, "Invalid mode!\n"); + exit(1); + } + free(T); + free(T2); + free(PP); + free(CC); + /*********************************************** { 구현 14 종료 } ********************************************/ +} diff --git a/source/keys/XTS_AES.h b/source/keys/XTS_AES.h new file mode 100644 index 0000000..65a1a09 --- /dev/null +++ b/source/keys/XTS_AES.h @@ -0,0 +1,10 @@ + +// 암호화 모드 +#define ENC 1 +// 복호화 모드 +#define DEC 0 + +typedef unsigned char BYTE; + +// 128비트 XTS_AES 암복호화 인터페이스 +void XTS_AES128(BYTE *plain, BYTE *cipher, unsigned int size, BYTE* key, int mode); \ No newline at end of file diff --git a/source/keys/keys.c b/source/keys/keys.c index 9f56e79..7c79310 100644 --- a/source/keys/keys.c +++ b/source/keys/keys.c @@ -43,6 +43,7 @@ #include "key_sources.inl" #include "ccrypto.h" +#include "XTS_AES.h" #include "../libs/fatfs/diskio.h" #include @@ -355,19 +356,22 @@ get_tsec: ; // Read in package2 header and get package2 real size. u8 *tmp = (u8 *)malloc(NX_EMMC_BLOCKSIZE); + u8 *tmp_copy = (u8 *)malloc(NX_EMMC_BLOCKSIZE); + nx_emmc_part_read(&storage, pkg2_part, 0, 1, tmp); + memcpy(tmp_copy, tmp, NX_EMMC_BLOCKSIZE); gfx_hexdump(0, tmp, NX_EMMC_BLOCKSIZE); - aes_xtsn_decrypt(tmp, NX_EMMC_BLOCKSIZE, bis_key[0], bis_key[0] + 0x10, pkg2_part->lba_end, pkg2_part->lba_start, NX_EMMC_BLOCKSIZE); - - gfx_hexdump(0, tmp, NX_EMMC_BLOCKSIZE); - + aes_xtsn_decrypt(tmp_copy, NX_EMMC_BLOCKSIZE, bis_key[0], bis_key[0] + 0x10, pkg2_part->lba_end, pkg2_part->lba_start, NX_EMMC_BLOCKSIZE); + + gfx_hexdump(0, tmp_copy, NX_EMMC_BLOCKSIZE); + memcpy(tmp_copy, tmp, NX_EMMC_BLOCKSIZE); DRESULT read_res; - read_res = disk_read_mod (tmp, 0, 1, &storage, pkg2_part, 9); + read_res = disk_read_mod (tmp_copy, 0, 1, &storage, pkg2_part, 9); switch (read_res) { @@ -392,10 +396,15 @@ get_tsec: ; break; } - gfx_hexdump(0, tmp, NX_EMMC_BLOCKSIZE); + gfx_hexdump(0, tmp_copy, NX_EMMC_BLOCKSIZE); + memcpy(tmp_copy, tmp, NX_EMMC_BLOCKSIZE); + // XTS_AES128(tmp_copy, tmp, NX_EMMC_BLOCKSIZE, bis_key[0], DEC); + // gfx_hexdump(0, tmp_copy, NX_EMMC_BLOCKSIZE); + free(tmp); + free(tmp_copy); goto pkg2_done; u32 *hdr_pkg2_raw = (u32 *)(tmp + 0x100);