函数返回matlab中的矢量
问题描述:
我有一个函数在MatLab中返回一个向量,问题是函数应该返回一个无符号整数值,我已经调试了我的代码,并且我意识到变量galois_value
在我做的时候变成了一个向量一个bitand
和一个bitxor
操作。我试图做一个typecast
把矢量变成一个无符号的值,但不起作用。我试图强制演员阵容,但不起作用。下面的功能:函数返回matlab中的矢量
function galois_value = galois_mul2(value)
hex = uint8(hex2dec('1B'));
temp = typecast(value, 'int8');
temp = bitshift(temp,-7);
temp = bitand(typecast(temp,'uint8'),hex);
galois_value = bitxor(bitshift(value,1),uint16(temp));
end
此函数的正确的输出应该是(这个输出来自于正在一个C代码):
96
210
97
224
119
194
192
156
196
195
102
10
10
117
235
213
49
57
235
79
172
5
23
62
111
188
223
128
113
133
128
102
30
238
226
31
输出我用MATLAB函数得到:
96 96
210 210
353 378
224 224
375 364
194 194
192 192
156 156
196 196
451 472
102 102
10 10
10 10
373 366
491 496
469 462
305 298
313 290
491 496
335 340
172 172
261 286
279 268
62 62
367 372
188 188
479 452
128 128
369 362
389 414
128 128
102 102
30 30
238 238
226 226
287 260
要显示的代码和调试功能:
%Key
key = {'00','01','02','03','04','05','06','07','08','09','0a','0b','0c','0d','0e','0f'};
for n = 1 : 16
keyU(n)=uint16(hex2dec(key(n)));
end
%State
state = {'00','11','22','33','44','55','66','77','88','99','aa','bb','cc','dd','ee','ff'};
for n = 1 : 16
stateU(n)=uint16(hex2dec(state(n)));
end
%Sbox
sbox = {'63','7c','77','7b','f2','6b','6f','c5','30','01','67','2b','fe','d7','ab','76','ca','82','c9','7d','fa','59','47','f0','ad','d4','a2','af','9c','a4','72','c0','b7','fd','93','26','36','3f','f7','cc','34','a5','e5','f1','71','d8','31','15','04','c7','23','c3','18','96','05','9a','07','12','80','e2','eb','27','b2','75','09','83','2c','1a','1b','6e','5a','a0','52','3b','d6','b3','29','e3','2f','84','53','d1','00','ed','20','fc','b1','5b','6a','cb','be','39','4a','4c','58','cf','d0','ef','aa','fb','43','4d','33','85','45','f9','02','7f','50','3c','9f','a8','51','a3','40','8f','92','9d','38','f5','bc','b6','da','21','10','ff','f3','d2','cd','0c','13','ec','5f','97','44','17','c4','a7','7e','3d','64','5d','19','73','60','81','4f','dc','22','2a','90','88','46','ee','b8','14','de','5e','0b','db','e0','32','3a','0a','49','06','24','5c','c2','d3','ac','62','91','95','e4','79','e7','c8','37','6d','8d','d5','4e','a9','6c','56','f4','ea','65','7a','ae','08','ba','78','25','2e','1c','a6','b4','c6','e8','dd','74','1f','4b','bd','8b','8a','70','3e','b5','66','48','03','f6','0e','61','35','57','b9','86','c1','1d','9e','e1','f8','98','11','69','d9','8e','94','9b','1e','87','e9','ce','55','28','df','8c','a1','89','0d','bf','e6','42','68','41','99','2d','0f','b0','54','bb','16'};
for n = 1 : 256
sboxU(n)=uint16(hex2dec(sbox(n)));
end
%Rcon
rcon = {'01','02','04','08','10','20','40','80','1b','36'};
for n = 1 : 10
rconU(n)=uint16(hex2dec(rcon(n)));
end
%Main AES Data Loop
for round = 1 : 10
%Add key + sbox
for i = 1 : 16
stateU(i)= sboxU(bitxor(stateU(i),keyU(i))+1);
end
%Shift Rows
buf1 = stateU(2);
stateU(2) = stateU(6);
stateU(6) = stateU(10);
stateU(10) = stateU(14);
stateU(14) = buf1;
buf1 = stateU(3);
buf2 = stateU(7);
stateU(3) = stateU(11);
stateU(7) = stateU(15);
stateU(11) = buf1;
stateU(15) = buf2;
buf1 = stateU(16);
stateU(16) = stateU(12);
stateU(12) = stateU(8);
stateU(8) = stateU(4);
stateU(4) = buf1;
%Process mixcolumn for all rounds but the last one
if round < 10
for j = 0 : 3
%Compute the current index
buf4 = (bitshift(j,2));
%buf1
aux1 = bitxor(stateU(buf4+1),stateU(buf4+2));
aux2 = bitxor(stateU(buf4+3),stateU(buf4+4));
buf1 = bitxor(aux1,aux2);
%buf2
buf2 = stateU(buf4+1);
%buf3
buf3 = bitxor(stateU(buf4+1),stateU(buf4+2));
buf3 = galois_mul2(buf3);
disp(buf3);
end
end
end
答
问题出现在第3行的galois_mul2函数中
temp = typecast(value,'int8'); 因为value有类型uint16输出的类型转换是两个元素。例如对于例如 (uint16(5),'int8')的输出是5 0 如果将main的第3,8,13,18行和galois_mul2函数的第3,6行的所有类型更改为uint8,则问题将得到解决。