Update main.rs

src/main.rs

@@ -1,3 +1,163 @@
+/*
+MIT License
+
+Copyright (c) 2023 Yvain Ramora
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+*/
+
+/* Importing libraries */
+use std::fs;
+use std::io::Read;
+use std::path::Path;
+use std::{env, usize};
+
+/* main function */
 fn main() {
-    println!("Hello, world!");
+    /* retrieves the arguments */
+    let args: Vec<String> = env::args().collect();
+
+    /* checks that the file to be dumped is actually given */
+    if args.len() < 2 {
+        println!("Please specify the name of the NSIS file to be dumped");
+        return;
+    }
+
+    /* retrieves the name of the file to be dumped */
+    let filename = &args[1];
+
+    /* checks that the file exists  */
+    let path = Path::new(filename);
+    if !path.exists() {
+        println!("The {} file does not exist.", filename);
+        return;
+    }
+
+    /* opens the given file */
+    let mut file = match fs::File::open(filename) {
+        Ok(file) => file,
+        Err(error) => {
+            println!("Error opening file: {}", error);
+            return;
+        }
+    };
+
+    /* read the given file */
+    let mut contents = Vec::new();
+    if let Err(error) = file.read_to_end(&mut contents) {
+        println!("Error reading file: {}", error);
+        return;
+    }
+
+    /* checks that the NSIS signatures are present */
+    let index = check_nsis_signatures(&contents);
+    if let Some(index) = index {
+        println!("NSIS signature found at index {}", index);
+
+        /* retrieves the zip file */
+        let mut zip = contents.split_off(index);
+
+        /* checks whether the certificate signature is present */
+        let certificate = check_certificate_signature(&zip);
+        if let Some(certificate) = certificate {
+            println!("certificate signature found at index {}", certificate);
+
+            /* remove the certificate section */
+            zip = (&zip[0..certificate - 12]).to_vec()
+        }
+
+        /* put the contents of the 7zip in dump.7z */
+        match fs::write("dump.7z", patch_7z(&zip)) {
+            Ok(_) => println!("The dump.7z file has been successfully created."),
+            Err(e) => println!(
+                "An error has occurred, the dump.7z file already exists, Error : {}",
+                e
+            ),
+        }
+    } else {
+        println!("No signature found.");
+    }
+}
+
+/* NSIS signature verification function */
+fn check_nsis_signatures(contents: &[u8]) -> Option<usize> {
+    /* store NSIS signatures */
+    const SIGNATURES: &[[u8; 16]; 4] = &[
+        [
+            0xEF, 0xBE, 0xAD, 0xDE, 0x6E, 0x73, 0x69, 0x73, 0x69, 0x6E, 0x73, 0x74, 0x61, 0x6C,
+            0x6C, 0x00,
+        ],
+        [
+            0xED, 0xBE, 0xAD, 0xDE, 0x4E, 0x75, 0x6C, 0x6C, 0x53, 0x6F, 0x66, 0x74, 0x49, 0x6E,
+            0x73, 0x74,
+        ],
+        [
+            0xEF, 0xBE, 0xAD, 0xDE, 0x4E, 0x75, 0x6C, 0x6C, 0x53, 0x6F, 0x66, 0x74, 0x49, 0x6E,
+            0x73, 0x74,
+        ],
+        [
+            0xEF, 0xBE, 0xAD, 0xDE, 0x4E, 0x75, 0x6C, 0x6C, 0x73, 0x6F, 0x66, 0x74, 0x49, 0x6E,
+            0x73, 0x74,
+        ],
+    ];
+
+    /* NSIS detection */
+    for (index, chunk) in contents.windows(16).enumerate() {
+        for signature in SIGNATURES.iter() {
+            if chunk == *signature {
+                return Some(index);
+            }
+        }
+    }
+
+    /* return None if no signature is found */
+    None
+}
+
+/* function to verify the certificate signature */
+fn check_certificate_signature(contents: &[u8]) -> Option<usize> {
+    /* store NSIS signatures */
+    const SIGNATURE: &[u8; 11] = &[
+        0x06, 0x09, 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x07, 0x02,
+    ];
+
+    /* CERTIFICATE detection */
+    for (index, chunk) in contents.windows(11).enumerate() {
+        if chunk == *SIGNATURE {
+            return Some(index);
+        }
+    }
+
+    /* return None if no signature is found */
+    None
+}
+
+/* function for patching 7zip by adding 4 bytes (0x00) */
+fn patch_7z(contents: &[u8]) -> Vec<u8> {
+    /* create an editable copy of the data */
+    let mut data = contents.to_vec();
+
+    /* loop to add the 4 bytes (0x00)*/
+    for _ in 0..4 {
+        data.insert(0, 0x00);
+    }
+
+    /* returns the patch bytes from the 7z file */
+    return data;
 }