From 4eae524e5ffdd7b0c1e7f04b637421a2a916be4a Mon Sep 17 00:00:00 2001
From: Jean-Marie 'Histausse' Mineau <histausse@protonmail.com>
Date: Wed, 11 Feb 2026 15:10:45 +0100
Subject: [PATCH] generate HTML page to show dex layout

---
 androscalpel/examples/map_layout.rs |  14 ++--
 androscalpel/src/lib.rs             |   2 +
 androscalpel/src/map_dex_file.rs    | 118 ++++++++++++++++++++++++++++
 3 files changed, 125 insertions(+), 9 deletions(-)
 create mode 100644 androscalpel/src/map_dex_file.rs

diff --git a/androscalpel/examples/map_layout.rs b/androscalpel/examples/map_layout.rs
index 49291d7..88830f5 100644
--- a/androscalpel/examples/map_layout.rs
+++ b/androscalpel/examples/map_layout.rs
@@ -23,18 +23,14 @@ fn main() {
         &cli.dex.into_os_string().into_string().unwrap(),
         &data,
         |_, _, _| None,
-        false,
+        true,
     )
     .unwrap();
     //load_apk(File::open(&cli.apk).unwrap(), |_, _, _| None, false).unwrap();
-    for (name, dex) in &apk.dex_files {
-        println!("{name}:");
+    for (_name, dex) in &apk.dex_files {
+        //println!("{name}:");
+
         #[cfg(feature = "map_dex_file")]
-        for (off, size, dscr) in dex.layout_map.iter() {
-            let end = off + *size as u32;
-            let mut dscr = dscr.clone();
-            dscr.truncate(100);
-            println!("0x{off:x} -> 0x{end:x}: {dscr}");
-        }
+        println!("{}", dex.html_layout())
     }
 }
diff --git a/androscalpel/src/lib.rs b/androscalpel/src/lib.rs
index f23e96d..5eb3f67 100644
--- a/androscalpel/src/lib.rs
+++ b/androscalpel/src/lib.rs
@@ -25,6 +25,8 @@ pub mod visitor;
 
 #[cfg(feature = "code-analysis")]
 pub mod code_analysis;
+#[cfg(feature = "map_dex_file")]
+pub mod map_dex_file;
 
 pub use annotation::*;
 pub use apk::*;
diff --git a/androscalpel/src/map_dex_file.rs b/androscalpel/src/map_dex_file.rs
new file mode 100644
index 0000000..9302c53
--- /dev/null
+++ b/androscalpel/src/map_dex_file.rs
@@ -0,0 +1,118 @@
+use crate::DexFile;
+
+static STYLE: &'static str = "
+.hex_table {
+    border-collapse: collapse;
+    border: 1px solid grey;
+
+    font-family: monospace;
+    padding: 1em;
+}
+.hex_offset {
+    background: #A2A2A2;
+    padding-right: 0;
+}
+.hex_space {
+    //padding-right: 1em;
+    padding-left: 1em;
+}
+.dex_dscr {
+    display: none;
+}
+.dex_dscr_container {
+  position: fixed;
+  display: block;
+  left: 25em;
+  top: 0px;
+}
+";
+
+impl DexFile {
+    pub fn html_layout(&self) -> String {
+        assert!(
+            self.bin_cache.is_some(),
+            "cache must not be none to display layout"
+        );
+        let mut lines = vec![];
+        let mut current_line = vec![];
+        let raw = self.bin_cache.as_ref().unwrap();
+        let mut current_chunk = 0;
+        for i in 0..(raw.len() as u32) {
+            // We assumes that chunks are sorted by offset and non overlapping
+            while !((self.layout_map[current_chunk].0 <= i)
+                && (i < self.layout_map[current_chunk].0 + self.layout_map[current_chunk].1 as u32))
+                && self.layout_map[current_chunk].0 <= i
+            {
+                current_chunk += 1;
+            }
+            let in_chunk = (self.layout_map[current_chunk].0 <= i)
+                && (i < self.layout_map[current_chunk].0 + self.layout_map[current_chunk].1 as u32);
+            if i % 16 == 0 {
+                current_line.push(format!("<td class=\"hex_offset\">{i:08x}</td>"));
+                current_line.push("<td class=\"hex_space\"></td>".to_string());
+            }
+            if i % 16 == 8 {
+                current_line.push("<td class=\"hex_space\"></td>".to_string());
+            }
+            let mut classes = vec!["hex_cel".to_string()];
+            if in_chunk {
+                classes.push(format!(
+                    "chunk_{}_{}",
+                    self.layout_map[current_chunk].0, self.layout_map[current_chunk].1
+                ));
+            }
+            current_line.push(format!(
+                "<td class=\"{}\">{:02x}</td>",
+                classes.join(" "),
+                raw[i as usize]
+            ));
+            if (i % 16 == 15) || (i == raw.len() as u32 - 1) {
+                let cells = current_line.join("\n      ");
+                current_line = vec![];
+                lines.push(format!(
+                    "    <tr>
+      {cells}
+    </tr>
+"
+                ))
+            }
+        }
+        let table = lines.join("\n");
+        let mut chunk_style_lines = vec![];
+        let mut data_lines = vec![];
+        for (off, size, dscr) in &self.layout_map {
+            let classname = format!("chunk_{off}_{size}");
+            chunk_style_lines.push(format!(
+                "html:has(.{classname}:hover) .{classname} {{ background-color: yellow; }}"
+            ));
+            chunk_style_lines.push(format!(
+                "html:has(.{classname}:hover) .dscr_{classname} {{ display: block; }}"
+            ));
+            data_lines.push(format!(
+                "<pre class=\"dex_dscr dscr_{classname}\"><code>{dscr}</code></pre>"
+            ))
+        }
+        let chunk_style = chunk_style_lines.join("\n  ");
+        let data = data_lines.join("\n    ");
+
+        format!(
+            "<html>
+<head>
+  <title>DEX layout</title>
+  <style>
+  {STYLE}
+  {chunk_style}
+  </style>
+</head>
+<body>
+  <table class=\"hex_table\">
+{table}
+  </table>
+  <div class=\"dex_dscr_container\">
+    {data}
+  </div>
+</body>
+</html>"
+        )
+    }
+}