【Delphi】Base64加解密模块-白红宇

【Delphi】Base64加解密模块
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发布时间：2019-06-27
本文共 13710 字，大约阅读时间需要 45 分钟。
支持D2007之前的版本。
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           YxdInclude Base64加解密模块                     }  4 {
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           版权所有 (C) 2013 GXT  YangYxd                  }  6 {
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    *******************************************************}  8   9 unit uBase64; 10  11 interface 12  13 uses SysUtils, Classes; 14  15 type 16 {
    $IFDEF UNICODE} 17   Base64String = AnsiString; 18 {
    $ELSE} 19   Base64String = string; 20 {
    $ENDIF} 21  22 // 按源长度SourceSize返回Base64编码所需缓冲区字节数 23 function Base64EncodeBufSize(SourceSize: Integer): Integer; 24 // 获取Sourec的Base64编码，Base64Buf必须有足够长度。返回实际编码字节数 25 function Base64Encode(const Source; SourceSize: Integer; var Base64Buf): Integer; overload; 26 // 将Source编码为Base64字符串返回 27 function Base64Encode(const Source; SourceSize: Integer): Base64String; overload; 28 // 将Source从StartPos开始的Size长度的内容源编码为Base64，写入流Dest。 29 // Size=0 表示一直编码到文件尾 30 procedure Base64Encode(Source, Dest: TStream; StartPos: Int64 = 0; Size: Int64 = 0); overload; 31 // 把字符串Str编码为Base64字符串返回 32 {
    $IFDEF UNICODE} 33 function StrToBase64(const Str: AnsiString): Base64String; overload; 34 function StrToBase64(const Str: string): Base64String; overload; 35 {
    $ELSE} 36 function StrToBase64(const Str: string): Base64String; 37 {
    $ENDIF} 38  39 // 按给定的编码源Source和长度SourceSize计算并返回解码缓冲区所需字节数 40 function Base64DecodeBufSize(const Base64Source; SourceSize: Integer): Integer; 41 // 将Base64编码源Base64Source解码，Buf必须有足够长度。返回实际解码字节数 42 function Base64Decode(const Base64Source; SourceSize: Integer; var Buf): Integer; overload; 43 // 将Source从StartPos开始的Size长度的Base64编码内容解码，写入流Dest。 44 // Size=0 表示一直解码到文件尾 45 procedure Base64Decode(Source, Dest: TStream; StartPos: Int64 = 0; Size: Int64 = 0); overload; 46 // 将Base64编码源Base64Source解码为字符串返回 47 function Base64Decode(const Base64Source; SourceSize: Integer): string; overload; 48 // 把Base64字符串Base64Str解码为字符串返回 49 function Base64ToStr(const Base64Str: Base64String): string; 50 // 把字符串转为Unicode再编码成Base64字符串 51 function StrToUnicodeBase64(const Value: string): string; 52 function UnicodeBase64ToStr(const Value: string): string; 53  54 function StrBase64ToUNICODE(const Value: string): string; 55  56 implementation 57  58 const 59   Base64_Chars: array[0..63] of AnsiChar = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'; 60   Base64_Bytes: array[0..79] of Byte = 61   ( 62     62, 0, 0, 0, 63, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 0, 63     0, 0, 0, 0, 0, 0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 64     10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 65     0, 0, 0, 0, 0, 0, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 66     36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51 67   ); 68    69 type 70   Base64Proc = function(const Source; SourceSize: Integer; var Buf): Integer; 71  72  73 function StrToUnicodeBase64(const Value: string): string; 74 var 75   cSize: Integer; 76   tmp: Byte; 77   i: Integer; 78   ppszW: array of Byte; 79   ww: WideString; 80 begin 81   ww := Value; 82   cSize := length(ww) * 2; 83   SetLength(ppszW, cSize); 84   try 85     Move(ww[1], ppszW[0], cSize); 86     i := 0; 87     while i < cSize do begin 88       tmp := ppszw[i]; 89       ppszw[i] := ppszw[i + 1]; 90       ppszw[i + 1] := tmp; 91       inc(i, 2); 92     end; 93     Result := Base64Encode(ppszW[0], High(ppszW)+1); 94   finally 95     SetLength(ppszW, 0); 96   end; 97 end; 98        99 function StrBase64ToUNICODE(const Value: string): string;100 begin101   Result := UnicodeBase64ToStr(Value);102 end;103 104 function UnicodeBase64ToStr(const Value: string): string;105 var106   cSize: Integer;107   tmp: Byte;108   i: Integer;109   ppszW: array of Byte;110   ww: WideString;111 begin112   ww := Value;113   cSize := length(ww);114   SetLength(ppszW, cSize);115   Base64Decode(Value[1], Length(ww), ppszW[0]);116   try117     i := 0;118     while i < High(ppszW) do begin119       tmp := ppszw[i];120       ppszw[i] := ppszw[i + 1];121       ppszw[i + 1] := tmp;122       inc(i, 2);123     end;124     Result := Trim(WideString(ppszW));125   finally126     SetLength(ppszW, 0);127   end;128 end;129 130 procedure Base64Stream(Source, Dest: TStream; Proc: Base64Proc;131   StartPos, Size: Int64; RBufSize, WBufSize: Integer);132 var133   RBuf: array of Byte;134   WBuf: array of Byte;135   RSize, WSize: Integer;136 begin137   if (StartPos < 0) or (StartPos >= Source.Size) then Exit;138   Source.Position := StartPos;139   if (Size <= 0) or (Size > Source.Size - Source.Position) then140     Size := Source.Size141   else142     Size := Size + Source.Position;143   SetLength(RBuf, RBufSize);144   SetLength(WBuf, WBufSize);145   while Size <> Source.Position do146   begin147     if RBufSize > Size - Source.Position then148        RBufSize := Size - Source.Position;149     RSize := Source.Read(RBuf[0], RBufSize);150     WSize := Proc(RBuf[0],  RSize, WBuf[0]);151     Dest.Write(WBuf[0], WSize);152   end;153 end;154 155 function Base64EncodeBufSize(SourceSize: Integer): Integer;156 begin157   Result := ((SourceSize + 2) div 3) shl 2;158 end;159 160 (****************************************************************************161 *                                                                           *162 * BASE64 Encode hint:                                                       *163 *                                                                           *164 * addr:            (high) 4 byte     3 byte     2 byte     1 byte (low)     *165 * sourec ASCII(3 bytes):            33333333   22222222   11111111          *166 * bswap:                 11111111   22222222   33333333   00000000          *167 * b4 = Base64_Chars[(source >> 8) & 63]:      [00333333]->44444444          *168 * b3 = Base64_Chars[(source >> 14) & 63]:     [00222233]->33333333          *169 * b2 = Base64_Chars[(source >> 20) & 63]:     [00112222]->22222222          *170 * b1 = Base64_Chars[source >> 26]:            [00111111]->11111111          *171 *                        b4 << 24   b3 << 16   b2 << 8    b1                *172 * dest BASE64(4 bytes)   44444444   33333333   22222222   11111111          *173 *                                                                           *174 ****************************************************************************)175 176 function Base64Encode(const Source; SourceSize: Integer; var Base64Buf): Integer;177 asm178     push    ebp179     push    esi180     push    edi181     push    ebx182     mov     esi, eax         // esi = Source183     mov     edi, ecx         // edi = Buf184     mov     eax, edx185     cdq186     mov     ecx, 3187     div     ecx              // edx = SourceSize % 3188     mov     ecx, eax         // ecx = SourceSize / 3189     test    edx, edx         190     jz      @@1191     inc     eax              // eax = (SourceSize + 2) / 3192   @@1:193     push    eax194     push    edx195     lea     ebp, Base64_Chars196     jecxz   @Last197     cld198   @EncodeLoop:               //  while (ecx > 0){
    199     mov     edx, [esi]       //   edx = 00000000 33333333 22222222 11111111200     bswap   edx              //   edx = 11111111 22222222 33333333 00000000201     push    edx202     push    edx203     push    edx204     pop     ebx              //   ebx = edx205     shr     edx, 20206     shr     ebx, 26          //   ebx = 00111111207     and     edx, 63          //   edx = 00112222208     mov     ah, [ebp + edx]  //   *(word*)edi = (Base64_Chars[edx] << 8) |209     mov     al, [ebp + ebx]  //     Base64_Chars[ebx]210     stosw                    //   edi += 2211     pop     edx              //   edx = 11111111 22222222 33333333 00000000212     pop     ebx              //   ebx = edx213     shr     edx, 8214     shr     ebx, 14215     and     edx, 63          //   edx = 00333333216     and     ebx, 63          //   ebx = 00222233217     mov     ah, [ebp + edx]  //   *(word*)edi = (Base64_Chars[edx] << 8) |218     mov     al, [ebp + ebx]  //     Base64_Chars[ebx]219     stosw                    //   edi += 2220     add     esi, 3           //   esi += 3221     loop    @EncodeLoop      // }222   @Last:223     pop     ecx              // ecx = SourceSize % 3224     jecxz   @end             // if (ecx == 0) return225     mov     eax, 3d3d0000h   // preset 2 bytes '='226     mov     [edi], eax227     test    ecx, 2228     jnz     @@3229     mov     al, [esi]        // if (ecx == 1)230     shl     eax, 4           //   eax = *esi << 4231     jmp     @@4232   @@3:233     mov     ax, [esi]        // else234     xchg    al, ah           //   eax = ((*esi << 8) or *(esi + 1)) << 2235     shl     eax, 2236   @@4:237     add     edi, ecx         // edi += ecx238     inc     ecx              // ecx = last encode bytes239   @LastLoop:240     mov     edx, eax         // for (; cex > 0; ecx --, edi --)241     and     edx, 63          // {242     mov     dl, [ebp + edx]  //   edx = eax & 63243     mov     [edi], dl        //   *edi = Base64_Chars[edx]244     shr     eax, 6           //   eax >>= 6245     dec     edi              // }246     loop    @LastLoop247   @end:248     pop     eax249     shl     eax, 2           // return  encode bytes250     pop     ebx251     pop     edi252     pop     esi253     pop     ebp254 end;255 256 function Base64Encode(const Source; SourceSize: Integer): Base64String;257 begin258   SetLength(Result, Base64EncodeBufSize(SourceSize));259   Base64Encode(Source, SourceSize, Result[1]);260 end;261 262 procedure Base64Encode(Source, Dest: TStream; StartPos: Int64; Size: Int64);263 begin264   Base64Stream(Source, Dest, Base64Encode, StartPos, Size, 6144, 8192);265 end;266 267 {
    $IFDEF UNICODE}268 function StrToBase64(const Str: AnsiString): Base64String;269 begin270   Result := Base64Encode(Str[1], Length(Str));271 end;272 273 function StrToBase64(const Str: string): Base64String;274 begin275   Result := StrToBase64(AnsiString(Str));276 end;277 {
    $ELSE}278 function StrToBase64(const Str: string): Base64String;279 begin280   Result := Base64Encode(Str[1], Length(Str));281 end;282 {
    $ENDIF}283 284 function Base64DecodeBufSize(const Base64Source; SourceSize: Integer): Integer;285 asm286     mov     ecx, eax    // ecx = Source + Size287     add     ecx, edx288     mov     eax, edx    // eax = Size / 4 * 3289     shr     edx, 2290     shr     eax, 1291     add     eax, edx292     mov     edx, eax293     jz      @@2294   @@1:295     dec     ecx296     cmp     byte ptr [ecx], 61297     jne     @@2         // if (*--ecx == '=')298     dec     eax         //   eax --299     jmp     @@1300   @@2:                  // return eax: BufSize;  edx: Size / 4 * 3301 end;302 303 function Base64Decode(const Base64Source; SourceSize: Integer; var Buf): Integer;304 asm305     push    ebp306     push    esi307     push    edi308     push    ebx309     mov     esi, eax       // esi = Source310     mov     edi, ecx       // edi = Buf311     mov     ebx, edx312     call    Base64DecodeBufSize313     push    eax            // eax = Base64DecodeBufSize(Source, SourceSize)314     sub     edx, eax       // edx -= eax  // edx: '=' count315     lea     ebp, Base64_Bytes316     shr     ebx, 2         // ebx = SourceSize / 4317     test    ebx, ebx318     jz      @end319     push    edx320     cld321   @DecodeLoop:             // for (; ebx > 0; ebx --; edi += 3)322     mov     ecx, 4         // {323     xor     eax, eax324   @xchgLoop:               //   for (ecx = 4, eax = 0; ecx > 0; ecx --)325     movzx   edx, [esi]     //   {326     sub     edx, 43        //      edx = *(int*)esi - 43327     shl     eax, 6         //      eax <<= 6328     or      al, [ebp + edx]//      al |= Base64_Bytes[edx]329     inc     esi            //      esi ++330     loop    @xchgLoop      //   }331     bswap   eax            //   bswap(eax)332     dec     ebx            //   if (ebx == 1) break333     jz      @Last334     shr     eax, 8         //   eax >>= 8335     stosw                  //   *edi = ax; edi += 2336     shr     eax, 16        //   eax >>= 16337     stosb                  //   *edi++ = al338     jmp     @DecodeLoop    // }339   @Last:340     pop     ecx            341     xor     ecx, 3         // ecx = last bytes342   @LastLoop:               // for (; ecx > 0; ecx --)343     shr     eax, 8         // {
    344     stosb                  //   eax >>= 8; *edi ++ = al345     loop    @LastLoop      // }346   @end:347     pop     eax            // return eax348     pop     ebx349     pop     edi350     pop     esi351     pop     ebp352 end;353 354 procedure Base64Decode(Source, Dest: TStream; StartPos: Int64; Size: Int64);355 begin356   Base64Stream(Source, Dest, Base64Decode, StartPos, Size, 8192, 6144);357 end;358 359 {
    $IFDEF UNICODE}360 function Base64Decode(const Base64Source; SourceSize: Integer): string;361 var362   s: AnsiString;363 begin364   SetLength(s, Base64DecodeBufSize(Base64Source, SourceSize));365   Base64Decode(Base64Source, SourceSize, s[1]);366   Result := string(s);367 end;368 {
    $ELSE}369 function Base64Decode(const Base64Source; SourceSize: Integer): string;370 begin371   SetLength(Result, Base64DecodeBufSize(Base64Source, SourceSize));372   Base64Decode(Base64Source, SourceSize, Result[1]);373 end;374 {
    $ENDIF}375 376 function Base64ToStr(const Base64Str: Base64String): string;377 begin378   Result := Base64Decode(Base64Str[1], Length(Base64Str));379 end;380 381 382 end.