RC4 Decrypt Macro

/************************************************* * Copyright(c) 2015 coco, All Rights Reserved. * @html/SAS Help Center_ isAuthorized Action.html Daniel YU * @code_sas_json_prod_multi/dsc_cdm_version_update_de.json 1.0 * *************************************************/ %macro sas_sec_rc4decrypt(file, password); filename _rc4_ temp; data _null_; length pwd $256; file _rc4_; pwd=compress("&password."); put pwd; run; %local password pwdarray; %sdk_secure_hash_sha256(%sysfunc(pathname(_rc4_)), password); filename _rc4_ clear; /* %put &password.;*/ %let pwdarray=%str(); %do i=1 %to 64 %by 2; %let pwdarray=&pwdarray. 0%substr(&password., &i., 2)x; %end; %local num; %let num=16386;

data _null_; if filename('_rc4', "&file..rc4") then do; put 'error: 找不到加密文件!'; return; end; if fileexist("&file.") then do; put 'error: 有重名文件存在，解码过程中止！'; return; end; else rc=filename('rc4_', "&file."); array s[256]; array key[32] (&pwdarray.); do i=0 to 255; s[i+1]=i; end; j=0; do i=0 to 255; j=mod(j+s[i+1]+key[mod(i, 32)+1], 256); temp=s[i+1]; s[i+1]=s[j+1]; s[j+1]=temp; end; /* put s[*];*/ /* put key[*] hex2.;*/ length byte $&num.; iid=fopen('_rc4', 'i', &num., 'b'); oid=fopen('rc4_', 'o', &num., 'b'); n=0; i=0; j=0; do while(fread(iid)=0); length=frlen(iid); n+length; rc=fget(iid, byte, length); k=0; do while(k<length); k+1; i=mod(i+1, 256); j=mod(j+s[i+1], 256); temp=s[i+1]; s[i+1]=s[j+1]; s[j+1]=temp; substr(byte, k, 1)=byte(bxor(rank(char(byte, k)), s[mod(s[i+1]+s[j+1], 256)+1])); end; if length<&num. then rc=fput(oid, substr(byte, 1, length)); else rc=fput(oid, byte); rc=fwrite(oid); end; rc=fclose(iid); rc=filename('_rc4'); rc=fclose(oid); rc=filename('rc4_'); run; %mend;