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-rw-r--r--blog/asm/1.html74
-rw-r--r--blog/c/cherry.html82
2 files changed, 104 insertions, 52 deletions
diff --git a/blog/asm/1.html b/blog/asm/1.html
index d46759f..fcaae55 100644
--- a/blog/asm/1.html
+++ b/blog/asm/1.html
@@ -3,7 +3,7 @@
 "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
 <html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en">
 <head>
-<!-- 2024-03-07 Thu 20:55 -->
+<!-- 2024-03-17 Sun 21:28 -->
 <meta http-equiv="Content-Type" content="text/html;charset=utf-8" />
 <meta name="viewport" content="width=device-width, initial-scale=1" />
 <title>x86 Assembly from my understanding</title>
@@ -23,9 +23,9 @@
 <p>
 Soooo this article (or maybe even a series of articles, who knows ?) will be about x86 assembly, or rather, what I understood from it and my road from the bottom-up hopefully reaching a good level of understanding
 </p>
-<div id="outline-container-org924bef5" class="outline-2">
-<h2 id="org924bef5">Memory :</h2>
-<div class="outline-text-2" id="text-org924bef5">
+<div id="outline-container-orgd547ad6" class="outline-2">
+<h2 id="orgd547ad6">Memory :</h2>
+<div class="outline-text-2" id="text-orgd547ad6">
 <p>
 Memory is a sequence of octets (Aka 8bits) that each have a unique integer assigned to them called <b>The Effective Address (EA)</b>, in this particular CPU Architecture (the i8086), the octet is designated by a couple (A segment number, and the offset in the segment)
 </p>
@@ -40,9 +40,9 @@ Memory is a sequence of octets (Aka 8bits) that each have a unique integer assig
 The offset and segment are encoded in 16bits, so they take a value between 0 and 65535
 </p>
 </div>
-<div id="outline-container-orgdfa99d1" class="outline-4">
-<h4 id="orgdfa99d1">Important :</h4>
-<div class="outline-text-4" id="text-orgdfa99d1">
+<div id="outline-container-org024e482" class="outline-4">
+<h4 id="org024e482">Important :</h4>
+<div class="outline-text-4" id="text-org024e482">
 <p>
 The relation between the Effective Address and the Segment &amp; Offset is as follow :
 </p>
@@ -52,10 +52,10 @@ The relation between the Effective Address and the Segment &amp; Offset is as fo
 </p>
 </div>
 <ul class="org-ul">
-<li><a id="org8845f88"></a>Example :<br />
-<div class="outline-text-5" id="text-org8845f88">
+<li><a id="org6cfa3c7"></a>Example :<br />
+<div class="outline-text-5" id="text-org6cfa3c7">
 <p>
-Let the Physical address (Or Effective Address, these two terms are enterchangeable) <b>12345h</b> (the h refers to Hexadecimal, which can also be written like this <b>0x12345</b>), the register <b>DS = 1230h</b> and the register <b>SI = 0045h</b>, the CPU calculates the physical address by multiplying the content of the segment register <b>DS</b> by 10h (or 16) and adding the content of the register <b>SI</b>. so we get : <b>1230h x 10h + 45h = 12345h</b>
+Let the Physical address (Or Effective Address, these two terms are interchangeable) <b>12345h</b> (the h refers to Hexadecimal, which can also be written like this <b>0x12345</b>), the register <b>DS = 1230h</b> and the register <b>SI = 0045h</b>, the CPU calculates the physical address by multiplying the content of the segment register <b>DS</b> by 10h (or 16) and adding the content of the register <b>SI</b>. so we get : <b>1230h x 10h + 45h = 12345h</b>
 </p>
 
 
@@ -66,16 +66,16 @@ Now if you are a clever one ( I know you are, since you are reading this &lt;3 )
 </li>
 </ul>
 </div>
-<div id="outline-container-org16ce372" class="outline-3">
-<h3 id="org16ce372">Registers</h3>
-<div class="outline-text-3" id="text-org16ce372">
+<div id="outline-container-org6b34cdf" class="outline-3">
+<h3 id="org6b34cdf">Registers</h3>
+<div class="outline-text-3" id="text-org6b34cdf">
 <p>
 The 8086 CPU has 14 registers of 16bits of size. From the POV of the user, the 8086 has 3 groups of 4 registers of 16bits. One state register of 9bits and a counting program of 16bits inaccessible to the user (whatever this means).
 </p>
 </div>
-<div id="outline-container-org8d1541d" class="outline-4">
-<h4 id="org8d1541d">General Registers</h4>
-<div class="outline-text-4" id="text-org8d1541d">
+<div id="outline-container-org67926ce" class="outline-4">
+<h4 id="org67926ce">General Registers</h4>
+<div class="outline-text-4" id="text-org67926ce">
 <p>
 General registers contribute to arithmetic&rsquo;s and logic and addressing too.
 </p>
@@ -126,28 +126,28 @@ Now here are the Registers we can find in this section:
 </div>
 </div>
 </div>
-<div id="outline-container-orgd61521c" class="outline-3">
-<h3 id="orgd61521c">Addressing and registers&#x2026;again</h3>
-<div class="outline-text-3" id="text-orgd61521c">
+<div id="outline-container-org824a260" class="outline-3">
+<h3 id="org824a260">Addressing and registers&#x2026;again</h3>
+<div class="outline-text-3" id="text-org824a260">
 </div>
-<div id="outline-container-orgc573bac" class="outline-4">
-<h4 id="orgc573bac">I realized what I wrote here before was almost gibberish, sooo here we go again I guess ?</h4>
-<div class="outline-text-4" id="text-orgc573bac">
+<div id="outline-container-orgaa8f029" class="outline-4">
+<h4 id="orgaa8f029">I realized what I wrote here before was almost gibberish, sooo here we go again I guess ?</h4>
+<div class="outline-text-4" id="text-orgaa8f029">
 <p>
 Well lets take a step back to the notion of effective addresses VS relative ones.
 </p>
 </div>
 </div>
-<div id="outline-container-org83b616a" class="outline-4">
-<h4 id="org83b616a">Effective = 10h x Segment + Offset . Part1</h4>
-<div class="outline-text-4" id="text-org83b616a">
+<div id="outline-container-org85a2533" class="outline-4">
+<h4 id="org85a2533">Effective = 10h x Segment + Offset . Part1</h4>
+<div class="outline-text-4" id="text-org85a2533">
 <p>
 When trying to access a specific memory space, we use this annotation <b>[Segment:Offset]</b>, so for example, and assuming <b>DS = 0100h</b>. We want to write the value <b>0x0005</b> to the memory space defined by the physical address <b>1234h</b>, what do we do ?
 </p>
 </div>
 <ul class="org-ul">
-<li><a id="orga0fd499"></a>Answer :<br />
-<div class="outline-text-5" id="text-orga0fd499">
+<li><a id="orgae0f70c"></a>Answer :<br />
+<div class="outline-text-5" id="text-orgae0f70c">
 <div class="org-src-container">
 <pre class="src src-asm"><span style="color: #89b4fa;">MOV</span> [DS:0234h], 0x0005
 </pre>
@@ -159,7 +159,7 @@ Why ? Let&rsquo;s break it down :
 
 
 
-<div id="orge5d4a33" class="figure">
+<div id="orgd01a20f" class="figure">
 <p><img src="../../src/gifs/lain-dance.gif" alt="lain-dance.gif" />
 </p>
 </div>
@@ -177,9 +177,9 @@ Simple, right ?, now for another example
 </li>
 </ul>
 </div>
-<div id="outline-container-org93b46d0" class="outline-4">
-<h4 id="org93b46d0">Another example :</h4>
-<div class="outline-text-4" id="text-org93b46d0">
+<div id="outline-container-org811633c" class="outline-4">
+<h4 id="org811633c">Another example :</h4>
+<div class="outline-text-4" id="text-org811633c">
 <p>
 What if we now have this instruction ?
 </p>
@@ -192,9 +192,9 @@ What does it do ? You might or might not be surprised that it does the exact sam
 </p>
 </div>
 </div>
-<div id="outline-container-orgcba10b0" class="outline-4">
-<h4 id="orgcba10b0">Segment + Register &lt;3</h4>
-<div class="outline-text-4" id="text-orgcba10b0">
+<div id="outline-container-orge6219c5" class="outline-4">
+<h4 id="orge6219c5">Segment + Register &lt;3</h4>
+<div class="outline-text-4" id="text-orge6219c5">
 <p>
 Consider <b>DS = 0100h</b> and <b>BX = BP = 0234h</b> and this code snippet:
 </p>
@@ -230,8 +230,8 @@ The General rule of thumb is as follows :
 </ul>
 </div>
 <ul class="org-ul">
-<li><a id="orgf6c5f3b"></a>Note<br />
-<div class="outline-text-5" id="text-orgf6c5f3b">
+<li><a id="orga9c3a1b"></a>Note<br />
+<div class="outline-text-5" id="text-orga9c3a1b">
 <p>
 The values of the registers CS DS and SS are automatically initialized by the OS when launching the program. So these segments are implicit. AKA : If we want to access a specific data in memory, we just need to specify its offset. Also you can&rsquo;t write directly into the DS or CS segment registers, so something like
 </p>
@@ -249,7 +249,7 @@ The values of the registers CS DS and SS are automatically initialized by the OS
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Crystal</p>
-<p class="date">Created: 2024-03-07 Thu 20:55</p>
+<p class="date">Created: 2024-03-17 Sun 21:28</p>
 </div>
 </body>
 </html>
diff --git a/blog/c/cherry.html b/blog/c/cherry.html
index 9b5da84..e2d9221 100644
--- a/blog/c/cherry.html
+++ b/blog/c/cherry.html
@@ -3,7 +3,7 @@
 "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
 <html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en">
 <head>
-<!-- 2024-03-16 Sat 21:42 -->
+<!-- 2024-03-17 Sun 21:46 -->
 <meta http-equiv="Content-Type" content="text/html;charset=utf-8" />
 <meta name="viewport" content="width=device-width, initial-scale=1" />
 <title>Reviving Caesar with a Cherry-flavored Crystal</title>
@@ -20,17 +20,17 @@
  <a accesskey="H" href="https://crystal.tilde.institute/"> HOME </a>
 </div><div id="content" class="content">
 <h1 class="title">Reviving Caesar with a Cherry-flavored Crystal</h1>
-<div id="outline-container-org394c654" class="outline-2">
-<h2 id="org394c654">What ?&#x2026;</h2>
-<div class="outline-text-2" id="text-org394c654">
+<div id="outline-container-org0bff230" class="outline-2">
+<h2 id="org0bff230">What ?&#x2026;</h2>
+<div class="outline-text-2" id="text-org0bff230">
 <p>
 That is probably your reaction reading this title, and no, this isn&rsquo;t a randomly generated sentence, but rather a simple encryption algorithm I recently made (Actually the first encryption algorithm i make at all!!). Meet <b>Cherry-Crystal Encryption</b>.
 </p>
 </div>
 </div>
-<div id="outline-container-org5a46ff7" class="outline-2">
-<h2 id="org5a46ff7">Okay so, what is this all about ?</h2>
-<div class="outline-text-2" id="text-org5a46ff7">
+<div id="outline-container-org4770304" class="outline-2">
+<h2 id="org4770304">Okay so, what is this all about ?</h2>
+<div class="outline-text-2" id="text-org4770304">
 <p>
 This encryption Algorithm that we will call <b>CCE</b> for short, takes inspiration from the Caesar cipher which needn&rsquo;t an introduction (you can find great explanations online). But what about mine you might ask ?
 </p>
@@ -44,15 +44,15 @@ This encryption Algorithm that we will call <b>CCE</b> for short, takes inspirat
 </ul>
 </div>
 </div>
-<div id="outline-container-org9e305ea" class="outline-2">
-<h2 id="org9e305ea">The Code :</h2>
-<div class="outline-text-2" id="text-org9e305ea">
+<div id="outline-container-org4496ca5" class="outline-2">
+<h2 id="org4496ca5">The Code :</h2>
+<div class="outline-text-2" id="text-org4496ca5">
 <div class="org-src-container">
 <pre class="src src-c"><span style="color: #f9e2af;">#include</span> <span style="color: #f38ba8;">&lt;</span><span style="color: #a6e3a1;">stdio.h</span><span style="color: #f38ba8;">&gt;</span>
 <span style="color: #f9e2af;">#include</span> <span style="color: #f38ba8;">&lt;</span><span style="color: #a6e3a1;">stdlib.h</span><span style="color: #f38ba8;">&gt;</span>
 <span style="color: #f9e2af;">#include</span> <span style="color: #f38ba8;">&lt;</span><span style="color: #a6e3a1;">string.h</span><span style="color: #f38ba8;">&gt;</span>
 
-<span style="color: #f9e2af;">void</span> <span style="color: #89b4fa;">encrypt</span><span style="color: #f38ba8;">(</span><span style="color: #f9e2af;">char</span> <span style="color: #cdd6f4;">cherry</span><span style="color: #fab387;">[]</span>, <span style="color: #f9e2af;">char</span> <span style="color: #cdd6f4;">crystal</span><span style="color: #fab387;">[]</span>, <span style="color: #f9e2af;">int</span> <span style="color: #cdd6f4;">mask</span><span style="color: #fab387;">[]</span><span style="color: #f38ba8;">)</span> <span style="color: #f38ba8;">{</span>
+<span style="color: #f9e2af;">void</span> <span style="color: #89b4fa;">sloth</span><span style="color: #f38ba8;">(</span><span style="color: #f9e2af;">char</span> <span style="color: #cdd6f4;">cherry</span><span style="color: #fab387;">[]</span>, <span style="color: #f9e2af;">char</span> <span style="color: #cdd6f4;">crystal</span><span style="color: #fab387;">[]</span>, <span style="color: #f9e2af;">int</span> <span style="color: #cdd6f4;">mask</span><span style="color: #fab387;">[]</span><span style="color: #f38ba8;">)</span> <span style="color: #f38ba8;">{</span>
   <span style="color: #f9e2af;">int</span> <span style="color: #cdd6f4;">i</span>;
   <span style="color: #cba6f7;">for</span> <span style="color: #fab387;">(</span>i = <span style="color: #fab387;">0</span>; i &lt; strlen<span style="color: #f9e2af;">(</span>cherry<span style="color: #f9e2af;">)</span> - <span style="color: #fab387;">1</span>; i++<span style="color: #fab387;">)</span> <span style="color: #fab387;">{</span>
     mask<span style="color: #f9e2af;">[</span>i<span style="color: #f9e2af;">]</span> = cherry<span style="color: #f9e2af;">[</span>i<span style="color: #f9e2af;">]</span> - crystal<span style="color: #f9e2af;">[</span>i<span style="color: #f9e2af;">]</span>;
@@ -61,7 +61,7 @@ This encryption Algorithm that we will call <b>CCE</b> for short, takes inspirat
     mask<span style="color: #f9e2af;">[</span>i<span style="color: #f9e2af;">]</span> = crystal<span style="color: #f9e2af;">[</span>i<span style="color: #f9e2af;">]</span>;
   <span style="color: #fab387;">}</span>
 <span style="color: #f38ba8;">}</span>
-<span style="color: #f9e2af;">void</span> <span style="color: #89b4fa;">decrypt</span><span style="color: #f38ba8;">(</span><span style="color: #f9e2af;">char</span> <span style="color: #cdd6f4;">cherry</span><span style="color: #fab387;">[]</span>, <span style="color: #f9e2af;">char</span> <span style="color: #cdd6f4;">crystal</span><span style="color: #fab387;">[]</span>, <span style="color: #f9e2af;">int</span> <span style="color: #cdd6f4;">mask</span><span style="color: #fab387;">[]</span>, <span style="color: #f9e2af;">int</span> <span style="color: #cdd6f4;">length</span><span style="color: #f38ba8;">)</span> <span style="color: #f38ba8;">{</span>
+<span style="color: #f9e2af;">void</span> <span style="color: #89b4fa;">moon</span><span style="color: #f38ba8;">(</span><span style="color: #f9e2af;">char</span> <span style="color: #cdd6f4;">cherry</span><span style="color: #fab387;">[]</span>, <span style="color: #f9e2af;">char</span> <span style="color: #cdd6f4;">crystal</span><span style="color: #fab387;">[]</span>, <span style="color: #f9e2af;">int</span> <span style="color: #cdd6f4;">mask</span><span style="color: #fab387;">[]</span>, <span style="color: #f9e2af;">int</span> <span style="color: #cdd6f4;">length</span><span style="color: #f38ba8;">)</span> <span style="color: #f38ba8;">{</span>
   <span style="color: #f9e2af;">int</span> <span style="color: #cdd6f4;">i</span>, <span style="color: #cdd6f4;">end</span> = <span style="color: #fab387;">1</span>;
   <span style="color: #cba6f7;">for</span> <span style="color: #fab387;">(</span>i = <span style="color: #fab387;">0</span>; i &lt; length; i++<span style="color: #fab387;">)</span> <span style="color: #fab387;">{</span>
     <span style="color: #cba6f7;">if</span> <span style="color: #f9e2af;">(</span>i == strlen<span style="color: #a6e3a1;">(</span>cherry<span style="color: #a6e3a1;">)</span> - <span style="color: #fab387;">1</span> || end == <span style="color: #fab387;">0</span><span style="color: #f9e2af;">)</span> <span style="color: #f9e2af;">{</span>
@@ -81,7 +81,7 @@ This encryption Algorithm that we will call <b>CCE</b> for short, takes inspirat
   fgets<span style="color: #fab387;">(</span>cherry, size, stdin<span style="color: #fab387;">)</span>;
   puts<span style="color: #fab387;">(</span><span style="color: #a6e3a1;">"Enter the Crystal: "</span><span style="color: #fab387;">)</span>;
   fgets<span style="color: #fab387;">(</span>crystal, size, stdin<span style="color: #fab387;">)</span>;
-  encrypt<span style="color: #fab387;">(</span>cherry, crystal, mask<span style="color: #fab387;">)</span>;
+  sloth<span style="color: #fab387;">(</span>cherry, crystal, mask<span style="color: #fab387;">)</span>;
   <span style="color: #cba6f7;">for</span> <span style="color: #fab387;">(</span>i = <span style="color: #fab387;">0</span>; i &lt; strlen<span style="color: #f9e2af;">(</span>crystal<span style="color: #f9e2af;">)</span> - <span style="color: #fab387;">1</span>; i++<span style="color: #fab387;">)</span> <span style="color: #fab387;">{</span>
     printf<span style="color: #f9e2af;">(</span><span style="color: #a6e3a1;">"%d "</span>, mask<span style="color: #a6e3a1;">[</span>i<span style="color: #a6e3a1;">]</span><span style="color: #f9e2af;">)</span>;
     length++;
@@ -97,7 +97,7 @@ This encryption Algorithm that we will call <b>CCE</b> for short, takes inspirat
     scanf<span style="color: #f9e2af;">(</span><span style="color: #a6e3a1;">"%d"</span>, &amp;mask2<span style="color: #a6e3a1;">[</span>i<span style="color: #a6e3a1;">]</span><span style="color: #f9e2af;">)</span>;
   <span style="color: #fab387;">}</span>
   puts<span style="color: #fab387;">(</span><span style="color: #a6e3a1;">"The Crystal is: "</span><span style="color: #fab387;">)</span>;
-  decrypt<span style="color: #fab387;">(</span>cherry2, crystal2, mask2, length<span style="color: #fab387;">)</span>;
+  moon<span style="color: #fab387;">(</span>cherry2, crystal2, mask2, length<span style="color: #fab387;">)</span>;
   puts<span style="color: #fab387;">(</span>crystal2<span style="color: #fab387;">)</span>;
   <span style="color: #cba6f7;">return</span> <span style="color: #fab387;">0</span>;
 <span style="color: #f38ba8;">}</span>
@@ -110,10 +110,62 @@ The program has been tested both on Alpine OS with Musl libc (thanks <a href="ht
 </p>
 </div>
 </div>
+<div id="outline-container-org6c3305a" class="outline-2">
+<h2 id="org6c3305a">How does it work ?</h2>
+<div class="outline-text-2" id="text-org6c3305a">
+</div>
+<div id="outline-container-orgf462a7c" class="outline-3">
+<h3 id="orgf462a7c">Slothing (Encrypting) 🦥:</h3>
+<div class="outline-text-3" id="text-orgf462a7c">
+<p>
+<del>What is it with these names I pick ?</del> Anyways, the <b>sloth(char *cherry, char *crystal, int *mask)</b> void function takes as parameters three variables:
+</p>
+
+<ul class="org-ul">
+<li>A pointer to a <b>char array</b> or simply said <b>a string</b>, It&rsquo;s the <b>Cherry</b>.</li>
+<li>Another pointer to the <b>Crystal</b>.</li>
+<li>And Finally, a pointer to an array of integers <b>The Mask</b> which will be output-ed by the function.</li>
+</ul>
+
+
+<p>
+The general idea of it is like this : (we will use a quick example)
+</p>
+
+<ul class="org-ul">
+<li><b>Cherry</b>:  H e l l o \0.</li>
+<li><b>Crystal</b>: W o r l d \0.</li>
+<li>Cherry[0] here is <b>H</b>, or in ASCII <b>72</b>. And Crystal[0] is <b>W</b> or <b>87</b>.</li>
+<li>Mask[0] in this case is : Cherry[0] - Crystal[0]. which is <b>-15</b>. We then repeat the same steps for each letter on the <b>Crystal</b>.</li>
+</ul>
+
+<p>
+Why the emphasis on <b>Crystal</b> ? Because we might end up with a case of a Crystal larger than a Cherry. we set the offset to the ASCII value of <b>Crystal[i]</b>, okay which to be fair is not the safest option out there, but I&rsquo;m planning on fixing it sooner or later. In the case of a large Cherry but a small Crystal&#x2026;it works but now looking at the code, i have no idea why it works the intended way&#x2026;.
+</p>
+</div>
+</div>
+<div id="outline-container-org7cb73ea" class="outline-3">
+<h3 id="org7cb73ea">Mooning (Decrypting) 🌕:</h3>
+<div class="outline-text-3" id="text-org7cb73ea">
+<p>
+The function <b>moon(char *cherry, char *crystal, int *mask, int length)</b> works the same way as the sloth function, but in reverse and a small change.
+</p>
+
+<ul class="org-ul">
+<li><b>The for loop goes through all the elements of the Mask and reconstructing the Crystal using the reverse equation of the encryption</b>. But when it arrives at the end of the <b>Cherry</b> (here we enter the case of a Cherry smaller than a Crystal). Then we will just assume that <b>Mask[i]</b> is the ASCII code of <b>Crystal[i]</b>, and we continue this assumption until the end of the loop.</li>
+</ul>
+
+
+<p>
+And voila that&rsquo;s it. Of course there might be some things I will change, but the overall concept is here!
+</p>
+</div>
+</div>
+</div>
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Crystal &amp; Sloth</p>
-<p class="date">Created: 2024-03-16 Sat 21:42</p>
+<p class="date">Created: 2024-03-17 Sun 21:46</p>
 </div>
 </body>
 </html>