91av视频/亚洲h视频/操亚洲美女/外国一级黄色毛片 - 国产三级三级三级三级

資源簡介

CRC32計算程序,生成多項式是: G(x)=x32+x26+x23+x22+x16+x12+x11+x10+x8+x7+x5+x4+x2+x+1 該生成多項式是IEEE的標準,應用在ETH,wifi等多個協議里面。 電腦上的文件校驗工具,也基本采用這個crc32. 用matlab實現,帶注釋。 包含little-endian、big-endian算法,已及相應的查表算法。 此外,還專門針對cksum、hashcalc這兩個常見的校驗軟件,寫了計算例子。 如果還在疑惑為什么cksum和crc32、hashcalc的結果不一樣,建議看一下這個程序。

資源截圖

代碼片段和文件信息

function?cksum
test1;
test2;
test3;
test4;
crctab?=?gen_tbl_le();
crctab?=?gen_tbl_be();


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%?test?1?little?endian?just?like?HashCalc.exe
function?test1

msg??=?[‘02‘;?‘02‘;?‘58‘;?‘60‘;
????????‘23‘;?‘5A‘;?‘3D‘;?‘6F‘;?
????????‘EA‘;?‘84‘;?‘E7‘;?‘AA‘;?
????????‘6C‘;?‘13‘;?‘E4‘;?‘15‘;?
????????‘EB‘;?‘D8‘;?‘C2‘;?‘34‘;?
????????‘A5‘;?‘12‘?];
ccc??=?[‘D8‘;?‘8B‘;?‘5D‘;?‘84‘];

msg??=?de2bi(hex2dec(msg)?8?‘left-msb‘);
ccc??=?de2bi(hex2dec(ccc)?8?‘left-msb‘);

%?generate?crc
crc?=?crc32_le(ones(132)?msg);
crc?=?1-crc(32:-1:1);
crc_hex?=?dec2hex(bi2de(crc));?%?845D8BD8
disp(crc_hex);

%?check?crc
crc?=?crc32_le(ones(132)?[msg;?ccc]);
crc_hex?=?dec2hex(bi2de(crc));?%?C704DD7B
disp(crc_hex);


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%?test?2?big?endian?ieee?eth?spec?example
function?test2

msg??=?[‘40‘;?‘40‘;?‘1A‘;?‘06‘;?
????????‘C4‘;?‘5A‘;?‘BC‘;?‘F6‘;?
????????‘57‘;?‘21‘;?‘E7‘;?‘55‘;?
????????‘36‘;?‘C8‘;?‘27‘;?‘A8‘;?
????????‘D7‘;?‘1B‘;?‘43‘;?‘2C‘;?
????????‘A5‘;?‘48‘?];
ccc??=?[‘1B‘;?‘D1‘;?‘BA‘;?‘21‘];

msg??=?de2bi(hex2dec(msg)?8?‘left-msb‘);
ccc??=?de2bi(hex2dec(ccc)?8?‘left-msb‘);

%?generate?crc
crc?=?crc32_be(ones(132)?msg);
crc?=?1-crc(32:-1:1);
crc_hex?=?dec2hex(bi2de(crc));?%?1BD1BA21
disp(crc_hex);

%?check?crc
crc?=?crc32_be(ones(132)?[msg;?ccc]);
crc?=?crc(32:-1:1);
crc_hex?=?dec2hex(bi2de(crc));?%?C704DD7B
disp(crc_hex);


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%?test?3?methord?of?linux?coreutil?cksum
function?test3

msg??=?[‘40‘;?‘40‘;?‘1A‘;?‘06‘;?
????????‘C4‘;?‘5A‘;?‘BC‘;?‘F6‘;?
????????‘57‘;?‘21‘;?‘E7‘;?‘55‘;?
????????‘36‘;?‘C8‘;?‘27‘;?‘A8‘;?
????????‘D7‘;?‘1B‘;?‘43‘;?‘2C‘;?
????????‘A5‘;?‘48‘?];

len??=?size(msg?1);
lenhex?=?[];
while?len>0
??tmp?=?mod(len?256);?%?len?&?0xFF
??len?=?bitshift(len?-8);?%?len>>8
??lenhex?=?[lenhex;?dec2hex(tmp?2)];
end

len??=?size(msg?1);
msg??=?[msg;?lenhex];?%?calc?crc32?include?length
msg??=?de2bi(hex2dec(msg)?8?‘left-msb‘);

%?generate?crc
crc?=?crc32_be(zeros(132)?msg);

crc_dec?=?bi2de(1-crc(32:-1:1));
disp(sprintf(‘%d?%d?filename‘?crc_dec?len));


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%?test?3?compare?width?table?methord
function?test4

%?little?endian
msg??=?[‘02‘;?‘02‘;?‘58‘;?‘60‘;
????????‘23‘;?‘5A‘;?‘3D‘;?‘6F‘;?
????????‘EA‘;?‘84‘;?‘E7‘;?‘AA‘;?
????????‘6C‘;?‘13‘;?‘E4‘;?‘15‘;?
????????‘EB‘;?‘D8‘;?‘C2‘;?‘34‘;?
????????‘A5‘;?‘12‘?];
msg??=?de2bi(hex2dec(msg)?8?‘left-msb‘);
crc1?=?crc32_le(ones(132)?msg);
crc2?=?crc32_le_tbl(ones(132)?msg);
crc1_hex?=?dec2hex(bi2de(1-crc1(32:-1:1)));
crc2_hex?=?dec2hex(bi2de(1-crc2(32:-1:1)));
disp([crc1_hex?‘??‘?crc2_hex]);

%?big?endian
msg??=?[‘40‘;?‘40‘;?‘1A‘;?‘06‘;?
????????‘C4‘;?‘5A‘;?‘B

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????文件????????5651??2013-06-20?11:49??crc32.m
?????文件???????12824??2013-06-21?13:34??cksum.m

評論

共有 條評論