Skip to content

Commit

Permalink
Site updated: 2018-05-06 20:20:34
Browse files Browse the repository at this point in the history
  • Loading branch information
@asanzjx
asanzjx committed May 6, 2018
1 parent 6840f6c commit a8bb3a8
Show file tree
Hide file tree
Showing 11 changed files with 23 additions and 23 deletions.
6 changes: 3 additions & 3 deletions 2016/02/04/2016-02-04-winserver2003 配置FTP，wampserver环境，wordpress等问题/index.html
View file
Original file line number Diff line number Diff line change
Expand Up @@ -68,7 +68,7 @@
<link href="/css/main.css?v=5.0.1" rel="stylesheet" type="text/css" />


<meta name="keywords" content="wordpress,Windows server 2003,FTP,wamperserver," />
<meta name="keywords" content="Windows server 2003,FTP,wamperserver,wordpress," />



Expand Down Expand Up @@ -385,14 +385,14 @@ <h1 class="post-title" itemprop="name headline">

<div class="post-tags">

<a href="/tags/wordpress/" rel="tag">#wordpress</a>

<a href="/tags/Windows-server-2003/" rel="tag">#Windows server 2003</a>

<a href="/tags/FTP/" rel="tag">#FTP</a>

<a href="/tags/wamperserver/" rel="tag">#wamperserver</a>

<a href="/tags/wordpress/" rel="tag">#wordpress</a>

</div>


Expand Down
16 changes: 8 additions & 8 deletions 2018/05/06/3PagingModeVtoP/index.html
View file
Original file line number Diff line number Diff line change
Expand Up @@ -106,17 +106,17 @@
VirtBox+win xp(切换PAE状态)
实验">
<meta property="og:image" content="https://asanzjx.github.io/images/3PagingModeVtoP/4K-32NonPAE.PNG">
<meta property="og:image" content="https://asanzjx.github.io/images/3PagingModeVtoP/4K32NonPAE.PNG">
<meta property="og:image" content="https://asanzjx.github.io/images/3PagingModeVtoP/va2ra2.PNG">
<meta property="og:image" content="https://asanzjx.github.io/images/3PagingModeVtoP/va2ra1.PNG">
<meta property="og:image" content="https://asanzjx.github.io/images/3PagingModeVtoP/va2ra3.PNG">
<meta property="og:image" content="https://asanzjx.github.io/images/3PagingModeVtoP/PDPT-base.PNG">
<meta property="og:image" content="https://asanzjx.github.io/images/3PagingModeVtoP/PDPTbase.PNG">
<meta property="og:image" content="https://asanzjx.github.io/images/3PagingModeVtoP/va2ra4.PNG">
<meta property="og:image" content="https://asanzjx.github.io/images/3PagingModeVtoP/va2ra5.PNG">
<meta property="og:image" content="https://asanzjx.github.io/images/3PagingModeVtoP/PML4T-BASE.PNG">
<meta property="og:image" content="https://asanzjx.github.io/images/3PagingModeVtoP/PML4TBASE.PNG">
<meta property="og:image" content="https://asanzjx.github.io/images/3PagingModeVtoP/1G2M4Kpage.PNG">
<meta property="og:image" content="https://asanzjx.github.io/images/3PagingModeVtoP/va2ra7.PNG">
<meta property="og:updated_time" content="2018-05-06T12:11:42.023Z">
<meta property="og:updated_time" content="2018-05-06T12:19:29.605Z">
<meta name="twitter:card" content="summary">
<meta name="twitter:title" content="三种分页模式(32bit,PAE,IA-32e)下的线性（虚拟）地址到物理地址的转换">
<meta name="twitter:description" content="为了更好管理更大的内存，现代操作系统和CPU硬件引入了保护模式。其中保护模式的分页机制通过内存管理单元（MMU，Memory Management Unit）实现了物理地址到线性（虚拟）地址的转换，这个转换过程也称地址翻译。而本文探讨线性地址到物理地址的转换过程，并通过实际操作来体现。
Expand All @@ -127,7 +127,7 @@
VirtBox+win xp(切换PAE状态)
实验">
<meta name="twitter:image" content="https://asanzjx.github.io/images/3PagingModeVtoP/4K-32NonPAE.PNG">
<meta name="twitter:image" content="https://asanzjx.github.io/images/3PagingModeVtoP/4K32NonPAE.PNG">



Expand Down Expand Up @@ -408,7 +408,7 @@ <h1><span id="32bit地址">32bit地址</span></h1><p>32bit的线性地址到物
<li>获取分配到的物理页地址：PTE index * + PT base addr，就可以找到存储物理页地址的页表项</li>
<li>物理页地址+物理页offset=物理地址</li>
</ol>
<p><img src="/images/3PagingModeVtoP/4K-32NonPAE.PNG" alt="32bit No PAE"></p>
<p><img src="/images/3PagingModeVtoP/4K32NonPAE.PNG" alt="32bit No PAE"></p>
<p>以未开启PAE的win xp下calc.exe为例，其入口地址为0x1012475，这个地址怎么来的呢，OD载入即可找到。因为没有ASLR，所以每次运行的地址是固定的。将0x1012475分成三部分:</p>
<ul>
<li>0x10</li>
Expand All @@ -418,7 +418,7 @@ <h1><span id="32bit地址">32bit地址</span></h1><p>32bit的线性地址到物
<p><img src="/images/3PagingModeVtoP/va2ra2.PNG" alt="0x1012475入口特征"></p>
<p><img src="/images/3PagingModeVtoP/va2ra1.PNG" alt="32bit地址转换过程"><br>根据上面两张图，可以看出物理地址0x145e8375处数据和0x1012475处数据一致</p>
<p>为了进一步验证是否数据是否一致，在Windbg下修改物理地址处数据，然后通过OD查看虚拟地址处的数据，发现也是一致变化的。<br><img src="/images/3PagingModeVtoP/va2ra3.PNG" alt="Windbg修改数据"></p>
<h1><span id="开启pae">开启PAE</span></h1><p>此时线性地址要拆分成四部分，高2位（PD index），中高9位（PT index）,中的（PTE index）,低12位（物理页偏移）。此时cr3[5:31]存储的是PDPT base addr。<br><img src="/images/3PagingModeVtoP/PDPT-base.PNG" alt="cr3 PDPT base"></p>
<h1><span id="开启pae">开启PAE</span></h1><p>此时线性地址要拆分成四部分，高2位（PD index），中高9位（PT index）,中的（PTE index）,低12位（物理页偏移）。此时cr3[5:31]存储的是PDPT base addr。<br><img src="/images/3PagingModeVtoP/PDPTbase.PNG" alt="cr3 PDPT base"></p>
<p>开启硬件的PAE选项，可以发现XP下多了”物理地址扩展”<br><img src="/images/3PagingModeVtoP/va2ra4.PNG" alt="开启PAE"></p>
<p>将0x1012475拆分成四部分：</p>
<ul>
Expand All @@ -436,7 +436,7 @@ <h1><span id="ia-32e地址转换">IA-32e地址转换</span></h1><p>此时64bit
<li>[21:13]（PTE index）</li>
<li>[12:0]（physical offset）</li>
</ul>
<p>此时cr3[5:31]存储的是PML4T base addr。<br><img src="/images/3PagingModeVtoP/PML4T-BASE.PNG" alt="cr3 PML4T base"></p>
<p>此时cr3[5:31]存储的是PML4T base addr。<br><img src="/images/3PagingModeVtoP/PML4TBASE.PNG" alt="cr3 PML4T base"></p>
<p>用以下这张图可以清晰明了表示：<br><img src="/images/3PagingModeVtoP/1G2M4Kpage.PNG" alt="1G2M4Kpage"></p>
<p>这里测试写了一段代码<br><figure class="highlight plain"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br></pre></td><td class="code"><pre><span class="line">#include &lt;cstdio&gt;</span><br><span class="line">#include &lt;iostream&gt;</span><br><span class="line"></span><br><span class="line">using namespace std;</span><br><span class="line"></span><br><span class="line">int main()</span><br><span class="line">&#123;</span><br><span class="line"> char szName[20] = &quot;HelloWorld&quot;;</span><br><span class="line"> printf(&quot;szName:0x%x\n&quot;, szName);</span><br><span class="line"> cout &lt;&lt; &quot;szName:&quot; &lt;&lt; &amp;szName &lt;&lt; endl;</span><br><span class="line"> getchar();</span><br><span class="line"> return 0;</span><br><span class="line">&#125;</span><br></pre></td></tr></table></figure></p>
<p>为什么这里要写个printf输出呢。因为在看雪论坛上看到一个帖子啊，讲x64位虚拟地址转换，用printf直接输出值，这样是不严谨的，因为printf直接输出的话，只能输出32bit地址，如果是64bit的话，高32bit会被截取掉的。看雪上那篇帖子测试的时候正好输出了32bit的地址，所以可以寻到物理地址。</p>
Expand Down
2 changes: 0 additions & 2 deletions about/index.html
View file
Original file line number Diff line number Diff line change
Expand Up @@ -73,8 +73,6 @@






<link rel="alternate" href="/atom.xml" title="Asan'world" type="application/atom+xml" />

Expand Down
10 changes: 5 additions & 5 deletions atom.xml
View file

Large diffs are not rendered by default.

2 changes: 2 additions & 0 deletions categories/index.html
View file
Original file line number Diff line number Diff line change
Expand Up @@ -73,6 +73,8 @@






<link rel="alternate" href="/atom.xml" title="Asan'world" type="application/atom+xml" />

Expand Down
2 changes: 1 addition & 1 deletion css/main.css
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1548,7 +1548,7 @@ pre .javascript .function {
width: 4px;
height: 4px;
border-radius: 50%;
background: #cd62fa;
background: #ffbaf2;
}
.links-of-blogroll {
font-size: 13px;
Expand Down
Binary file added images/3PagingModeVtoP/4K32NonPAE.PNG
View file
Loading
Sorry, something went wrong. Reload?
Sorry, we cannot display this file.
Sorry, this file is invalid so it cannot be displayed.
Binary file added images/3PagingModeVtoP/PDPTbase.PNG
View file
Loading
Sorry, something went wrong. Reload?
Sorry, we cannot display this file.
Sorry, this file is invalid so it cannot be displayed.
Binary file added images/3PagingModeVtoP/PML4TBASE.PNG
View file
Loading
Sorry, something went wrong. Reload?
Sorry, we cannot display this file.
Sorry, this file is invalid so it cannot be displayed.
6 changes: 3 additions & 3 deletions index.html
View file
Original file line number Diff line number Diff line change
Expand Up @@ -382,7 +382,7 @@ <h1><span id="32bit地址">32bit地址</span></h1><p>32bit的线性地址到物
<li>获取分配到的物理页地址：PTE index * + PT base addr，就可以找到存储物理页地址的页表项</li>
<li>物理页地址+物理页offset=物理地址</li>
</ol>
<p><img src="/images/3PagingModeVtoP/4K-32NonPAE.PNG" alt="32bit No PAE"></p>
<p><img src="/images/3PagingModeVtoP/4K32NonPAE.PNG" alt="32bit No PAE"></p>
<p>以未开启PAE的win xp下calc.exe为例，其入口地址为0x1012475，这个地址怎么来的呢，OD载入即可找到。因为没有ASLR，所以每次运行的地址是固定的。将0x1012475分成三部分:</p>
<ul>
<li>0x10</li>
Expand All @@ -392,7 +392,7 @@ <h1><span id="32bit地址">32bit地址</span></h1><p>32bit的线性地址到物
<p><img src="/images/3PagingModeVtoP/va2ra2.PNG" alt="0x1012475入口特征"></p>
<p><img src="/images/3PagingModeVtoP/va2ra1.PNG" alt="32bit地址转换过程"><br>根据上面两张图，可以看出物理地址0x145e8375处数据和0x1012475处数据一致</p>
<p>为了进一步验证是否数据是否一致，在Windbg下修改物理地址处数据，然后通过OD查看虚拟地址处的数据，发现也是一致变化的。<br><img src="/images/3PagingModeVtoP/va2ra3.PNG" alt="Windbg修改数据"></p>
<h1><span id="开启pae">开启PAE</span></h1><p>此时线性地址要拆分成四部分，高2位（PD index），中高9位（PT index）,中的（PTE index）,低12位（物理页偏移）。此时cr3[5:31]存储的是PDPT base addr。<br><img src="/images/3PagingModeVtoP/PDPT-base.PNG" alt="cr3 PDPT base"></p>
<h1><span id="开启pae">开启PAE</span></h1><p>此时线性地址要拆分成四部分，高2位（PD index），中高9位（PT index）,中的（PTE index）,低12位（物理页偏移）。此时cr3[5:31]存储的是PDPT base addr。<br><img src="/images/3PagingModeVtoP/PDPTbase.PNG" alt="cr3 PDPT base"></p>
<p>开启硬件的PAE选项，可以发现XP下多了”物理地址扩展”<br><img src="/images/3PagingModeVtoP/va2ra4.PNG" alt="开启PAE"></p>
<p>将0x1012475拆分成四部分：</p>
<ul>
Expand All @@ -410,7 +410,7 @@ <h1><span id="ia-32e地址转换">IA-32e地址转换</span></h1><p>此时64bit
<li>[21:13]（PTE index）</li>
<li>[12:0]（physical offset）</li>
</ul>
<p>此时cr3[5:31]存储的是PML4T base addr。<br><img src="/images/3PagingModeVtoP/PML4T-BASE.PNG" alt="cr3 PML4T base"></p>
<p>此时cr3[5:31]存储的是PML4T base addr。<br><img src="/images/3PagingModeVtoP/PML4TBASE.PNG" alt="cr3 PML4T base"></p>
<p>用以下这张图可以清晰明了表示：<br><img src="/images/3PagingModeVtoP/1G2M4Kpage.PNG" alt="1G2M4Kpage"></p>
<p>这里测试写了一段代码<br><figure class="highlight plain"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br></pre></td><td class="code"><pre><span class="line">#include &lt;cstdio&gt;</span><br><span class="line">#include &lt;iostream&gt;</span><br><span class="line"></span><br><span class="line">using namespace std;</span><br><span class="line"></span><br><span class="line">int main()</span><br><span class="line">&#123;</span><br><span class="line"> char szName[20] = &quot;HelloWorld&quot;;</span><br><span class="line"> printf(&quot;szName:0x%x\n&quot;, szName);</span><br><span class="line"> cout &lt;&lt; &quot;szName:&quot; &lt;&lt; &amp;szName &lt;&lt; endl;</span><br><span class="line"> getchar();</span><br><span class="line"> return 0;</span><br><span class="line">&#125;</span><br></pre></td></tr></table></figure></p>
<p>为什么这里要写个printf输出呢。因为在看雪论坛上看到一个帖子啊，讲x64位虚拟地址转换，用printf直接输出值，这样是不严谨的，因为printf直接输出的话，只能输出32bit地址，如果是64bit的话，高32bit会被截取掉的。看雪上那篇帖子测试的时候正好输出了32bit的地址，所以可以寻到物理地址。</p>
Expand Down
2 changes: 1 addition & 1 deletion sitemap.xml
View file
Original file line number Diff line number Diff line change
Expand Up @@ -4,7 +4,7 @@
<url>
<loc>https://asanzjx.github.io/2018/05/06/3PagingModeVtoP/</loc>

<lastmod>2018-05-06T12:11:42.023Z</lastmod>
<lastmod>2018-05-06T12:19:29.605Z</lastmod>

</url>

Expand Down

0 comments on commit a8bb3a8

Please sign in to comment.