////////////////////////////////////////////////////////////
unit DES;
interface
uses
Windows, Classes, SysUtils;
type
fdArray = array of dword;
function des(key:string;smessage:string;encrypt:dword;mode:dword;iv:string):string;
function des_createKeys(key:string):fdArray;
function StrToHex(Str:string):string;
function HexToStr(Hex:string):string;
function IsInt(Str:String):Boolean;
implementation
function des(key:string;smessage:string;encrypt:dword;mode:dword;iv:string):string;
const
spfunction1 : array[0..63] of dword = ($1010400,0,$10000,$1010404,$1010004,$10404,$4,$10000,$400,$1010400,$1010404,$400,$1000404,$1010004,$1000000,$4,
$404,$1000400,$1000400,$10400,$10400,$1010000,$1010000,$1000404,$10004,$1000004,$1000004,$10004,0,$404,$10404,$1000000,$10000,$1010404,$4,$1010000,$1010400,
$1000000,$1000000,$400,$1010004,$10000,$10400,$1000004,$400,$4,$1000404,$10404,$1010404,$10004,$1010000,$1000404,$1000004,$404,$10404,$1010400,$404,
$1000400,$1000400,0,$10004,$10400,0,$1010004);
spfunction2 : array[0..63] of dword = ($80108020,$80008000,$8000,$108020,$100000,$20,$80100020,$80008020,$80000020,$80108020,$80108000,$80000000,
$80008000,$100000,$20,$80100020,$108000,$100020,$80008020,0,$80000000,$8000,$108020,$80100000,$100020,$80000020,0,$108000,$8020,$80108000,$80100000,$8020,0,
$108020,$80100020,$100000,$80008020,$80100000,$80108000,$8000,$80100000,$80008000,$20,$80108020,$108020,$20,$8000,$80000000,$8020,$80108000,$100000,
$80000020,$100020,$80008020,$80000020,$100020,$108000,0,$80008000,$8020,$80000000,$80100020,$80108020,$108000);
spfunction3 : array[0..63] of dword = ($208,$8020200,0,$8020008,$8000200,0,$20208,$8000200,$20008,$8000008,$8000008,$20000,$8020208,$20008,$8020000,$208,
$8000000,$8,$8020200,$200,$20200,$8020000,$8020008,$20208,$8000208,$20200,$20000,$8000208,$8,$8020208,$200,$8000000,$8020200,$8000000,$20008,$208,$20000,
$8020200,$8000200,0,$200,$20008,$8020208,$8000200,$8000008,$200,0,$8020008,$8000208,$20000,$8000000,$8020208,$8,$20208,$20200,$8000008,$8020000,$8000208,
$208,$8020000,$20208,$8,$8020008,$20200);
spfunction4 : array[0..63] of dword = ($802001,$2081,$2081,$80,$802080,$800081,$800001,$2001,0,$802000,$802000,$802081,$81,0,$800080,$800001,$1,$2000,
$800000,$802001,$80,$800000,$2001,$2080,$800081,$1,$2080,$800080,$2000,$802080,$802081,$81,$800080,$800001,$802000,$802081,$81,0,0,$802000,$2080,$800080,
$800081,$1,$802001,$2081,$2081,$80,$802081,$81,$1,$2000,$800001,$2001,$802080,$800081,$2001,$2080,$800000,$802001,$80,$800000,$2000,$802080);
spfunction5 : array[0..63] of dword = ($100,$2080100,$2080000,$42000100,$80000,$100,$40000000,$2080000,$40080100,$80000,$2000100,$40080100,$42000100,
$42080000,$80100,$40000000,$2000000,$40080000,$40080000,0,$40000100,$42080100,$42080100,$2000100,$42080000,$40000100,0,$42000000,$2080100,$2000000,
$42000000,$80100,$80000,$42000100,$100,$2000000,$40000000,$2080000,$42000100,$40080100,$2000100,$40000000,$42080000,$2080100,$40080100,$100,$2000000,
$42080000,$42080100,$80100,$42000000,$42080100,$2080000,0,$40080000,$42000000,$80100,$2000100,$40000100,$80000,0,$40080000,$2080100,$40000100);
spfunction6 : array[0..63] of dword = ($20000010,$20400000,$4000,$20404010,$20400000,$10,$20404010,$400000,$20004000,$404010,$400000,$20000010,$400010,
$20004000,$20000000,$4010,0,$400010,$20004010,$4000,$404000,$20004010,$10,$20400010,$20400010,0,$404010,$20404000,$4010,$404000,$20404000,$20000000,
$20004000,$10,$20400010,$404000,$20404010,$400000,$4010,$20000010,$400000,$20004000,$20000000,$4010,$20000010,$20404010,$404000,$20400000,$404010,
$20404000,0,$20400010,$10,$4000,$20400000,$404010,$4000,$400010,$20004010,0,$20404000,$20000000,$400010,$20004010);
spfunction7 : array[0..63] of dword = ($200000,$4200002,$4000802,0,$800,$4000802,$200802,$4200800,$4200802,$200000,0,$4000002,$2,$4000000,$4200002,$802,
$4000800,$200802,$200002,$4000800,$4000002,$4200000,$4200800,$200002,$4200000,$800,$802,$4200802,$200800,$2,$4000000,$200800,$4000000,$200800,$200000,
$4000802,$4000802,$4200002,$4200002,$2,$200002,$4000000,$4000800,$200000,$4200800,$802,$200802,$4200800,$802,$4000002,$4200802,$4200000,$200800,0,$2,
$4200802,0,$200802,$4200000,$800,$4000002,$4000800,$800,$200002);
spfunction8 : array[0..63] of dword = ($10001040,$1000,$40000,$10041040,$10000000,$10001040,$40,$10000000,$40040,$10040000,$10041040,$41000,$10041000,
$41040,$1000,$40,$10040000,$10000040,$10001000,$1040,$41000,$40040,$10040040,$10041000,$1040,0,0,$10040040,$10000040,$10001000,$41040,$40000,$41040,$40000,
$10041000,$1000,$40,$10040040,$1000,$41040,$10001000,$40,$10000040,$10040000,$10040040,$10000000,$40000,$10001040,0,$10041040,$40040,$10000040,$10040000,
$10001000,$10001040,0,$10041040,$41000,$41000,$1040,$1040,$40040,$10000000,$10041000);
var
keys:fdArray;
m, i, j:integer;
temp, temp2, right1, right2, left, right:dword;
looping:array of integer;
cbcleft, cbcleft2, cbcright, cbcright2:dword;
endloop, loopinc:integer;
len, iterations:integer;
chunk:integer;
tempresult:string;
begin
//create the 16 or 48 subkeys we will need
keys := des_createKeys(key);
m:=0;cbcleft:=0;cbcleft2:=0;cbcright:=0;cbcright2:=0;chunk:=0;
len := length(smessage);
//set up the loops for single and triple des
if length(keys) = 32 then
iterations := 3
else
iterations := 9;
if iterations = 3 then
begin
if encrypt = 1 then
begin
setlength(looping,3);
looping[0] := 0;
looping[1] := 32;
looping[2] := 2;
end
else
begin
setlength(looping,3);
looping[0] := 30;
looping[1] := -2;
looping[2] := -2;
end;
end
else
begin
if encrypt = 1 then
begin
setlength(looping,9);
looping[0] := 0;
looping[1] := 32;
looping[2] := 2;
looping[3] := 62;
looping[4] := 30;
looping[5] := -2;
looping[6] := 64;
looping[7] := 96;
looping[8] := 2;
end
else
begin
setlength(looping,9);
looping[0] := 94;
looping[1] := 62;
looping[2] := -2;
looping[3] := 32;
looping[4] := 64;
looping[5] := 2;
looping[6] := 30;
looping[7] := -2;
looping[8] := -2;
end;
end;
smessage := smessage + #0#0#0#0#0#0#0#0; //pad the message out with null bytes
//store the result here
result := '';
tempresult := '';
if mode = 1 then //CBC mode
begin
cbcleft := (ord(iv[m+1]) shl 24) or (ord(iv[m+2]) shl 16) or (ord(iv[m+3]) shl 8) or ord(iv[m+4]);
cbcright := (ord(iv[m+5]) shl 24) or (ord(iv[m+6]) shl 16) or (ord(iv[m+7]) shl 8) or ord(iv[m+8]);
m:=0;
end;
//loop through each 64 bit chunk of the message
while m < len do
begin
left := (ord(smessage[m+1]) shl 24) or (ord(smessage[m+2]) shl 16) or (ord(smessage[m+3]) shl 8) or ord(smessage[m+4]);
right := (ord(smessage[m+5]) shl 24) or (ord(smessage[m+6]) shl 16) or (ord(smessage[m+7]) shl 8) or ord(smessage[m+8]);
m := m + 8;
//for Cipher Block Chaining mode, xor the message with the previous result
if mode = 1 then
if encrypt=1 then
begin
left := left xor cbcleft;
right := right xor cbcright;
end
else
begin
cbcleft2 := cbcleft;
cbcright2 := cbcright;
cbcleft := left;
cbcright := right;
end;
//first each 64 but chunk of the message must be permuted according to IP
temp := ((left shr 4) xor right) and $0f0f0f0f; right := right xor temp; left := left xor (temp shl 4);
temp := ((left shr 16) xor right) and $0000ffff; right := right xor temp; left := left xor (temp shl 16);
temp := ((right shr 2) xor left) and $33333333; left := left xor temp; right := right xor (temp shl 2);
temp := ((right shr 8) xor left) and $00ff00ff; left := left xor temp; right := right xor (temp shl 8);
temp := ((left shr 1) xor right) and $55555555; right := right xor temp; left := left xor (temp shl 1);
left := ((left shl 1) or (left shr 31));
right := ((right shl 1) or (right shr 31));
//do this either 1 or 3 times for each chunk of the message
j:=0;
while j<iterations do
begin
endloop := looping[j+1];
loopinc := looping[j+2];
//now go through and perform the encryption or decryption
i:= looping[j];
while i<>endloop do
begin
right1 := right xor keys<i>;
right2 := ((right shr 4) or (right shl 28)) xor keys[i+1];
//the result is attained by passing these bytes through the S selection functions
temp := left;
left := right;
right := temp xor (spfunction2[(right1 shr 24) and $3f] or spfunction4[(right1 shr 16) and $3f]
or spfunction6[(right1 shr 8) and $3f] or spfunction8[right1 and $3f]
or spfunction1[(right2 shr 24) and $3f] or spfunction3[(right2 shr 16) and $3f]
or spfunction5[(right2 shr 8) and $3f] or spfunction7[right2 and $3f]);
i:=i+loopinc;
end;
temp := left; left := right; right := temp; //unreverse left and right
j:=j+3;
end; //for either 1 or 3 iterations
//move then each one bit to the right
left := ((left shr 1) or (left shl 31));
right := ((right shr 1) or (right shl 31));
//now perform IP-1, which is IP in the opposite direction
temp := ((left shr 1) xor right) and $55555555; right := right xor temp; left :=left xor (temp shl 1);
temp := ((right shr 8) xor left) and $00ff00ff; left := left xor temp; right := right xor (temp shl 8);
temp := ((right shr 2) xor left) and $33333333; left := left xor temp; right := right xor (temp shl 2);
temp := ((left shr 16) xor right) and $0000ffff; right := right xor temp; left := left xor (temp shl 16);
temp := ((left shr 4) xor right) and $0f0f0f0f; right := right xor temp; left := left xor (temp shl 4);
//for Cipher Block Chaining mode, xor the message with the previous result
if mode = 1 then
if encrypt=1 then
begin
cbcleft := left; cbcright := right;
end
else
begin
left :=left xor cbcleft2;
right := right xor cbcright2;
end;
tempresult := tempresult + chr(left shr 24) + chr((left shr 16) and $ff) + chr((left shr 8) and $ff) + chr(left and $ff) + chr(right shr 24) + chr
((right shr 16) and $ff) + chr((right shr 8) and $ff) + chr(right and $ff);
chunk := chunk + 8;
if chunk = 512 then
begin
result := result + tempresult; tempresult := ''; chunk := 0;
end;
end; //for every 8 characters, or 64 bits in the message
//return the result as an array
result := result + tempresult;
end; //end of des
//des_createKeys
//this takes as input a 64 bit key (even though only 56 bits are used)
//as an array of 2 dwords, and returns 16 48 bit keys
function des_createKeys(key:string):fdArray;
const
//declaring this locally speeds things up a bit
pc2bytes0 :array[0..15] of dword= (0,$4,$20000000,$20000004,$10000,$10004,$20010000,$20010004,$200,$204,$20000200,$20000204,$10200,$10204,$20010200,
$20010204);
pc2bytes1 :array[0..15] of dword= (0,$1,$100000,$100001,$4000000,$4000001,$4100000,$4100001,$100,$101,$100100,$100101,$4000100,$4000101,$4100100,
$4100101);
pc2bytes2 :array[0..15] of dword= (0,$8,$800,$808,$1000000,$1000008,$1000800,$1000808,0,$8,$800,$808,$1000000,$1000008,$1000800,$1000808);
pc2bytes3 :array[0..15] of dword= (0,$200000,$8000000,$8200000,$2000,$202000,$8002000,$8202000,$20000,$220000,$8020000,$8220000,$22000,$222000,$8022000,
$8222000);
pc2bytes4 :array[0..15] of dword= (0,$40000,$10,$40010,0,$40000,$10,$40010,$1000,$41000,$1010,$41010,$1000,$41000,$1010,$41010);
pc2bytes5 :array[0..15] of dword= (0,$400,$20,$420,0,$400,$20,$420,$2000000,$2000400,$2000020,$2000420,$2000000,$2000400,$2000020,$2000420);
pc2bytes6 :array[0..15] of dword= (0,$10000000,$80000,$10080000,$2,$10000002,$80002,$10080002,0,$10000000,$80000,$10080000,$2,$10000002,$80002,$10080002);
pc2bytes7 :array[0..15] of dword= (0,$10000,$800,$10800,$20000000,$20010000,$20000800,$20010800,$20000,$30000,$20800,$30800,$20020000,$20030000,
$20020800,$20030800);
pc2bytes8 :array[0..15] of dword= (0,$40000,0,$40000,$2,$40002,$2,$40002,$2000000,$2040000,$2000000,$2040000,$2000002,$2040002,$2000002,$2040002);
pc2bytes9 :array[0..15] of dword= (0,$10000000,$8,$10000008,0,$10000000,$8,$10000008,$400,$10000400,$408,$10000408,$400,$10000400,$408,$10000408);
pc2bytes10 :array[0..15] of dword= (0,$20,0,$20,$100000,$100020,$100000,$100020,$2000,$2020,$2000,$2020,$102000,$102020,$102000,$102020);
pc2bytes11 :array[0..15] of dword= (0,$1000000,$200,$1000200,$200000,$1200000,$200200,$1200200,$4000000,$5000000,$4000200,$5000200,$4200000,$5200000,
$4200200,$5200200);
pc2bytes12 :array[0..15] of dword= (0,$1000,$8000000,$8001000,$80000,$81000,$8080000,$8081000,$10,$1010,$8000010,$8001010,$80010,$81010,$8080010,$8081010);
pc2bytes13 :array[0..15] of dword= (0,$4,$100,$104,0,$4,$100,$104,$1,$5,$101,$105,$1,$5,$101,$105);
//now define the left shifts which need to be done
shifts :array[0..15] of dword = (0, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0);
var
iterations:integer;
keys:fdArray;
lefttemp, righttemp, temp:dword;
m, n, j,i:integer;
left,right:dword;
begin
//how many iterations (1 for des, 3 for triple des)
if length(key) = 24 then
iterations := 3
else
iterations := 1;
//stores the return keys
setlength(keys,32 * iterations);
//other variables
m:=0;n:=0;
for j:=0 to iterations-1 do //either 1 or 3 iterations
begin
left := (ord(key[m+1]) shl 24) or (ord(key[m+2]) shl 16) or (ord(key[m+3]) shl 8) or ord(key[m+4]);
right := (ord(key[m+5]) shl 24) or (ord(key[m+6]) shl 16) or (ord(key[m+7]) shl 8) or ord(key[m+8]);
m:=m+8;
temp := ((left shr 4) xor right) and $0f0f0f0f; right :=right xor temp; left :=left xor (temp shl 4);
temp := ((right shr 16) xor left) and $0000ffff; left := left xor temp; right :=right xor (temp shl 16);
temp := ((left shr 2) xor right) and $33333333; right :=right xor temp; left := left xor (temp shl 2);
temp := ((right shr 16) xor left) and $0000ffff; left :=left xor temp; right := right xor (temp shl 16);
temp := ((left shr 1) xor right) and $55555555; right := right xor temp; left := left xor (temp shl 1);
temp := ((right shr 8) xor left) and $00ff00ff; left :=left xor temp; right := right xor (temp shl 8);
temp := ((left shr 1) xor right) and $55555555; right :=right xor temp; left := left xor (temp shl 1);
//the right side needs to be shifted and to get the last four bits of the left side
temp := (left shl 8) or ((right shr 20) and $000000f0);
//left needs to be put upside down
left := (right shl 24) or ((right shl 8) and $ff0000) or ((right shr 8) and $ff00) or ((right shr 24) and $f0);
right := temp;
//now go through and perform these shifts on the left and right keys
for i:=low(shifts) to high(shifts) do
begin
//shift the keys either one or two bits to the left
if shifts<i> > 0 then
begin
left := (left shl 2) or (left shr 26);
right := (right shl 2) or (right shr 26);
//left := left shl 0;
//right:= right shl 0;
end
else
begin
left := (left shl 1) or (left shr 27);
right := (right shl 1) or (right shr 27);
//left := left shl 0;
//right:= right shl 0;
end;
left := left and $fffffff0;
right:= right and $fffffff0;
//now apply PC-2, in such a way that E is easier when encrypting or decrypting
//this conversion will look like PC-2 except only the last 6 bits of each byte are used
//rather than 48 consecutive bits and the order of lines will be according to
//how the S selection functions will be applied: S2, S4, S6, S8, S1, S3, S5, S7
lefttemp := pc2bytes0[left shr 28] or pc2bytes1[(left shr 24) and $f]
or pc2bytes2[(left shr 20) and $f] or pc2bytes3[(left shr 16) and $f]
or pc2bytes4[(left shr 12) and $f] or pc2bytes5[(left shr 8) and $f]
or pc2bytes6[(left shr 4) and $f];
righttemp := pc2bytes7[right shr 28] or pc2bytes8[(right shr 24) and $f]
or pc2bytes9[(right shr 20) and $f] or pc2bytes10[(right shr 16) and $f]
or pc2bytes11[(right shr 12) and $f] or pc2bytes12[(right shr 8) and $f]
or pc2bytes13[(right shr 4) and $f];
temp := ((righttemp shr 16) xor lefttemp) and $0000ffff;
keys[n+0] := lefttemp xor temp;
keys[n+1] := righttemp xor (temp shl 16);
n:=n+2;
end;
end; //for each iterations
//return the keys we've created
Result := keys;
end;//end of des_createKeys
function StrToHex(Str:string):string;
var
i:integer;
begin
result := '';
for i := 1 to length(Str) do
result := result + IntToHex(Ord(Str<i>), 2);
end;
function HexToStr(Hex:string):string;
var
i:Integer;
begin
Result := '';
for i := 1 to length(Hex) div 2 do
if IsInt('$' + Hex[i * 2 - 1] + Hex[i * 2]) then
Result := Result + Chr(StrToInt('$' + Hex[i * 2 - 1] + Hex[i * 2]));
end;
function IsInt(Str:String):Boolean;
begin
result := True;
try
StrToInt(Str);
except
result := False
end;
end;
end.
测试代码：
procedure TForm1.FormCreate(Sender: TObject); begin //大小写 //showmessage(Unit2.HexToStr('83af8c3f5507e100b182f90f5f5d834b94ef769c040b1b65')); //showmessage(Unit2.des('this is a 24 byte key !!','This is a test message',1,0,'')); Edit1.Text := Unit2.StrToHex(Unit2.des('this is a 24 byte key !!','This is a test message',1,0,'')); end; |