實(shí)現(xiàn)調(diào)用加殼的外殼中的子程序的一點(diǎn)見解

<P class=MsoNormal><SPAN style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">加殼往往是實(shí)現(xiàn)對(duì)原</SPAN><SPAN lang=EN-US>PE</SPAN><SPAN style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">的節(jié)數(shù)據(jù)加密、壓縮，若能加殼的同時(shí)，讓加殼后的程序調(diào)用殼中的某些子程序，那加殼強(qiáng)度大大增加。這樣處理后，即使脫掉了殼，程序執(zhí)行也肯定不正常，因?yàn)槊摎さ耐瑫r(shí)也將這些子程序脫掉了！</SPAN><SPAN lang=EN-US> </SPAN></P>
* f4 o% f' n2 X- V: _# Y/ v' ^<P class=MsoNormal><SPAN lang=EN-US><SPAN style="mso-spacerun: yes">&nbsp;&nbsp;&nbsp; </SPAN></SPAN><SPAN style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">怎樣實(shí)現(xiàn)呢？作為探討性的介紹，還是搞一個(gè)最基本的來說（假設(shè)現(xiàn)在您已經(jīng)會(huì)寫</SPAN><SPAN lang=EN-US>PE-exe</SPAN><SPAN style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">、</SPAN><SPAN lang=EN-US>PE-dll</SPAN><SPAN style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">等</SPAN><SPAN lang=EN-US>PE</SPAN><SPAN style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">加殼程序）：</SPAN><SPAN lang=EN-US> </SPAN></P>
<P class=MsoNormal><SPAN lang=EN-US><SPAN style="mso-spacerun: yes">&nbsp;&nbsp;&nbsp; </SPAN></SPAN><SPAN style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">我的實(shí)現(xiàn)是這樣的：作為一個(gè)</SPAN><SPAN lang=EN-US>PE</SPAN><SPAN style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">文件，多多少少程序中會(huì)有</SPAN><SPAN lang=EN-US>mov eax,1</SPAN><SPAN style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">或</SPAN><SPAN lang=EN-US>mov eax,0</SPAN><SPAN style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">的語句，就是從這里開刀，因?yàn)?lt;/SPAN><SPAN lang=EN-US>mov eax,xxxxxxxx</SPAN><SPAN style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">這樣的指令長度正好與</SPAN><SPAN lang=EN-US>Call xxxxxxxx</SPAN><SPAN style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">指令的長度一樣，處理起來相對(duì)簡單。在加殼程序加殼時(shí)，查找這些語句統(tǒng)統(tǒng)換成：</SPAN><SPAN lang=EN-US> </SPAN></P>
' `3 G5 h1 X% {3 j<P class=MsoNormal><SPAN lang=EN-US>call shellSub </SPAN></P>
) O% D4 O- A; k: f' z1 r. S% b<P class=MsoNormal><SPAN lang=EN-US>// </SPAN></P>
" F; c; r+ I3 Y8 p3 G<P class=MsoNormal><SPAN lang=EN-US>shellSub</SPAN><SPAN style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">實(shí)現(xiàn)如下：</SPAN><SPAN lang=EN-US> </SPAN></P>
<P class=MsoNormal><SPAN lang=EN-US>shellSub() </SPAN></P>
) k' N5 f! h2 o1 c1 G: @<P class=MsoNormal><SPAN lang=EN-US>{ </SPAN></P>
& o5 M% I+ h- U( m+ Q) @<P class=MsoNormal><SPAN lang=EN-US><SPAN style="mso-spacerun: yes">&nbsp; </SPAN>mov eax,1 </SPAN><SPAN style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">或</SPAN><SPAN lang=EN-US> mov eax,0 </SPAN></P>
<P class=MsoNormal><SPAN lang=EN-US>} </SPAN></P>
<P class=MsoNormal><SPAN lang=EN-US><SPAN style="mso-spacerun: yes">&nbsp;&nbsp;&nbsp; </SPAN></SPAN><SPAN style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">當(dāng)然，這里有個(gè)問題是怎樣計(jì)算這個(gè)</SPAN><SPAN lang=EN-US>Call xxxxxxxx</SPAN><SPAN style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">的</SPAN><SPAN lang=EN-US>xxxxxxxx</SPAN><SPAN style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">，其實(shí)想一想也很簡單，加殼時(shí)候我們已經(jīng)計(jì)算出了外殼程序的入口</SPAN><SPAN lang=EN-US>RVA</SPAN><SPAN style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">，只要以這個(gè)</SPAN><SPAN lang=EN-US>RVA</SPAN><SPAN style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">為基準(zhǔn)，就可以得到</SPAN><SPAN lang=EN-US>:(shellSub</SPAN><SPAN style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">的</SPAN><SPAN lang=EN-US>RVA)-(mov eax,1</SPAN><SPAN style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">的</SPAN><SPAN lang=EN-US>RVA)</SPAN><SPAN style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">的差值，這個(gè)差值再減去</SPAN><SPAN lang=EN-US>5</SPAN><SPAN style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">（</SPAN><SPAN lang=EN-US>Call</SPAN><SPAN style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">的指令長度）就是</SPAN><SPAN lang=EN-US>xxxxxxxx</SPAN><SPAN style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">。</SPAN><SPAN lang=EN-US> </SPAN></P>
6 W# s( p3 @* I: {& d; Q* _<P class=MsoNormal><SPAN lang=EN-US><SPAN style="mso-spacerun: yes">&nbsp;&nbsp;&nbsp; </SPAN></SPAN><SPAN style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">這里僅僅拋磚引玉的介紹了最基本的方法，其實(shí)通過變化，可以對(duì)原程序的很多特定語句實(shí)現(xiàn)改成調(diào)用外殼中不同的</SPAN><SPAN lang=EN-US>sub</SPAN><SPAN style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">，大大增加了外殼的保密強(qiáng)度。</SPAN><SPAN lang=EN-US> </SPAN></P>
0 Q! _& q, e8 C/ g0 j( i, W<P class=MsoNormal><SPAN lang=EN-US><SPAN style="mso-spacerun: yes">&nbsp;&nbsp;&nbsp; </SPAN></SPAN><SPAN style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">這樣處理后，可想而知，脫殼后的運(yùn)行情況：</SPAN><SPAN lang=EN-US>Windows</SPAN><SPAN style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">錯(cuò)誤，某個(gè)地址不能為讀或?qū)憽?。呵呵，要的就是這個(gè)效果?。?！</SPAN><SPAN lang=EN-US> </SPAN></P>
<P class=MsoNormal><SPAN lang=EN-US><SPAN style="mso-spacerun: yes">&nbsp;&nbsp;&nbsp; </SPAN></SPAN><SPAN style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">錯(cuò)誤之處，懇請(qǐng)各位高手指正！</SPAN><SPAN lang=EN-US> </SPAN></P>