通过对结果的排序，没有出现同一个BASE64编码对应不同的十六进制的情况，因此我们知道了可以用这个SQL为基础，通过用不同的SOURCE串来产生替换表的内容。
根据上面的SQL首先建一个表来存储替换表的内容，
CREATE TABLE SYS.IDLTRANSLATE
(
C_BASE64DECODE VARCHAR2(2) NOT NULL,
C_LZDEFLATECODE VARCHAR2(2) NULL
)
/
然后写一段PLSQL块来生成替换表的内容：
declare
nCnt integer;
nLoop integer;
nSLoop integer;
nCharmax integer;
nCharmin integer;
vChar Varchar2(3);
cursor getchar is
with src AS ( select ‘PACKAGE ‘||vChar txt from dual ),
wrap as ( select src.txt , dbms_ddl.wrap( ‘create ‘ || src.txt ) wrap from src ),
subst as (select substr( utl_encode.base64_decode( utl_raw.cast_to_raw(rtrim( substr( wrap.wrap, instr( wrap.wrap, chr( 10 ), 1, 20 ) + 1 ), chr(10) ) ) ), 41 ) x,
mycompress.deflate( wrap.txt || chr(0), 9 ) d
from wrap )
select substr( x, r * 2 – 1, 2 ) xr ,
substr( d, r * 2 – 1, 2 ) dr
from subst , ( select rownum r from dual connect by rownum <= ( select length( x ) / 2 from subst ) );
begin
nCharmax:=97;
nCharmin:=122;
For nLoop In 97..122 Loop
For nSloop In 0..99 Loop
vChar := chr(nLoop)||to_char(nSloop);
For abc In getchar Loop
Select Count(*) Into nCnt From sys.idltranslate WHERE c_base64decode = abc.xr;
If nCnt < 1 Then
Insert INTO sys.idltranslate VALUES (abc.xr,abc.dr);
Commit;
Else
Select Count(*) Into ncnt From sys.idltranslate WHERE c_base64decode = abc.xr AND c_lzdeflatecode=abc.dr;
If nCnt < 1 Then
DBMS_OUTPUT.PUT_LINE(‘wrong orginal char:’||vchar||’ hex base64:’||abc.xr);
End If;
End If;
End Loop;
End Loop;
End Loop;
end;
运行上面这段SQL大概会产生100多条记录，还未达到00-FF总共256条记录的要求，建议替换select ‘PACKAGE ‘||vChar txt from dual中的PACKAGE关健字为procedure或者function类似的，继续运行直到替换表中有不重复的256条记录为止。有了替换表的内容，unwrap出明文也就不再困难了。
利用前面得出的JAVA包以及转换表，结合下面这段代码unwrap出明文，如下
set serveroutput on;
create or replace procedure unwrap(o in varchar,n in varchar, t in varchar)
as
vWrappedtext Varchar2(32767);
vtrimtext Varchar2(32767);
vChar Varchar2(2);
vRepchar Varchar2(2);
vLZinflatestr Varchar2(32767);
nLen Integer;
nLoop Integer;
nCnt Integer;
code varchar(512);
Begin
code:=’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’;–sys.idltranslate表内容存到字符数组
vtrimtext:=”;
select count(*) into ncnt from DBA_SOURCE
Where owner=o
And Name = n
And Type=t ;
if ncnt >0 and ncnt <=5 then
for i in 1..ncnt loop
if i=1 then
select rtrim(substr(TEXT,instr(TEXT,chr(10),1,20)+1),chr(10)) –保存去掉前边20行的BASE64码正文
into vLZinflatestr
from DBA_SOURCE
Where owner=o
And Name = n
And Type=t and line=i;
else
select text into vLZinflatestr
from DBA_SOURCE
Where owner=o
And Name = n
And Type=t and line=i;
end if;
vtrimtext:=vtrimtext||vLZinflatestr;
end loop;
end if;
vtrimtext:=replace(vtrimtext,chr(10),”);
nLen := Length(vtrimtext)/256 ;
vWrappedtext :=”;
for i in 0..nLen loop
–if i< nLen then
vWrappedtext:=vWrappedtext||utl_encode.base64_decode( utl_raw.cast_to_raw(substrb(vtrimtext,256*i+1 , 256 ))) ;
– else
–vWrappedtext:=vWrappedtext||utl_encode.base64_decode( utl_raw.cast_to_raw(substrb(vtrimtext,64*i+1 ))) ;
–end if;
–DBMS_OUTPUT.PUT_LINE(vWrappedtext);
End Loop;
–vWrappe