Added iospatcher to lib and CLI

Everything but the no-shared flag is working right now. Getting no-shared to work properly will take a little more work because right now there's nothing to guarantee that the content records are synced between the TMD and content objects in a title. This means that updating any content in a title will result in the records being out of sync and the written TMD will not match the actual state of the content when it was dumped.
To mitigate this, I intend on making the content records in the content struct a reference to the content records in the TMD, so that they are the same object and therefore always in sync.

src/bin/playground/main.rs

@@ -7,8 +7,15 @@ use rustwii::archive::u8;
 // use rustii::title::content;
 
 fn main() {
-    let data = fs::read("sm.wad").unwrap();
-    let title = title::Title::from_bytes(&data).unwrap();
+    let data = fs::read("ios9.wad").unwrap();
+    let mut title = title::Title::from_bytes(&data).unwrap();
+
+    let index = title::iospatcher::ios_find_module(String::from("ES:"), &title).unwrap();
+    println!("ES index: {}", index);
+
+    let patch_count = title::iospatcher::ios_patch_sigchecks(&mut title, index).unwrap();
+    println!("patches applied: {}", patch_count);
+
     println!("Title ID from WAD via Title object: {}", hex::encode(title.tmd.title_id()));
 
     let wad = wad::WAD::from_bytes(&data).unwrap();
@@ -41,16 +48,9 @@ fn main() {
 
     let result = title.verify().unwrap();
     println!("full title verified successfully: {}", result);
-    
-    
 
     let u8_archive = u8::U8Directory::from_bytes(fs::read("testu8.arc").unwrap().into_boxed_slice()).unwrap();
     println!("{:#?}", u8_archive);
-    // println!("files and dirs counted: {}", u8_archive.node_tree.borrow().count());
-    // fs::write("outfile.arc", u8_archive.to_bytes().unwrap()).unwrap();
-    // println!("re-written");
-    
-    
     
     // let mut content_map = content::SharedContentMap::from_bytes(&fs::read("content.map").unwrap()).unwrap();
     // content_map.add(&[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]).unwrap();

src/bin/rustwii/archive/ash.rs

@@ -1,7 +1,7 @@
 // archive/ash.rs from ruswtii (c) 2025 NinjaCheetah & Contributors
 // https://github.com/NinjaCheetah/rustwii
 //
-// Code for the ASH decompression command in the rustii CLI.
+// Code for the ASH decompression command in the rustwii CLI.
 // Might even have the compression command someday if I ever write the compression code!
 
 use std::{str, fs};

src/bin/rustwii/archive/lz77.rs

@@ -1,7 +1,7 @@
 // archive/lz77.rs from ruswtii (c) 2025 NinjaCheetah & Contributors
 // https://github.com/NinjaCheetah/rustwii
 //
-// Code for the LZ77 compression/decompression commands in the rustii CLI.
+// Code for the LZ77 compression/decompression commands in the rustwii CLI.
 
 use std::{str, fs};
 use std::path::{Path, PathBuf};

src/bin/rustwii/archive/theme.rs

@@ -1,7 +1,7 @@
 // archive/theme.rs from ruswtii (c) 2025 NinjaCheetah & Contributors
 // https://github.com/NinjaCheetah/rustwii
 //
-// Code for the theme building commands in the rustii CLI.
+// Code for the theme building commands in the rustwii CLI.
 
 use std::collections::HashMap;
 use std::fs;

src/bin/rustwii/archive/u8.rs

@@ -1,7 +1,7 @@
 // archive/u8.rs from ruswtii (c) 2025 NinjaCheetah & Contributors
 // https://github.com/NinjaCheetah/rustwii
 //
-// Code for the U8 packing/unpacking commands in the rustii CLI.
+// Code for the U8 packing/unpacking commands in the rustwii CLI.
 
 use std::{str, fs};
 use std::path::{Path, PathBuf};

src/bin/rustwii/info.rs

@@ -1,7 +1,7 @@
 // info.rs from ruswtii (c) 2025 NinjaCheetah & Contributors
 // https://github.com/NinjaCheetah/rustwii
 //
-// Code for the info command in the rustii CLI.
+// Code for the info command in the rustwii CLI.
 
 use std::{str, fs};
 use std::path::Path;

src/bin/rustwii/main.rs

@@ -1,7 +1,7 @@
 // main.rs from ruswtii (c) 2025 NinjaCheetah & Contributors
 // https://github.com/NinjaCheetah/rustwii
 //
-// Base for the rustii CLI that handles argument parsing and directs execution to the proper module.
+// Base for the rustwii CLI that handles argument parsing and directs execution to the proper module.
 
 mod archive;
 mod title;
@@ -36,7 +36,7 @@ enum Commands {
     Fakesign {
         /// The path to a TMD, Ticket, or WAD
         input: String,
-        /// An (optional) output name; defaults to overwriting input file if not provided
+        /// An optional output path; defaults to overwriting input file if not provided
         #[arg(short, long)]
         output: Option<String>,
     },
@@ -45,6 +45,25 @@ enum Commands {
         /// The path to a TMD, Ticket, or WAD
         input: String,
     },
+    /// Apply patches to an IOS
+    IosPatch {
+        /// The IOS WAD to apply patches to
+        input: String,
+        #[arg(short, long)]
+        /// An optional output path; default to overwriting input file if not provided
+        output: Option<String>,
+        /// Set a new IOS version (0-65535)
+        #[arg(short, long)]
+        version: Option<u16>,
+        /// Set the slot that this IOS will install into
+        #[arg(short, long)]
+        slot: Option<u8>,
+        /// Set all patched content to be non-shared
+        #[arg(short, long, action)]
+        no_shared: bool,
+        #[command(flatten)]
+        enabled_patches: title::iospatcher::EnabledPatches,
+    },
     /// Compress/decompress data using LZ77 compression
     Lz77 {
         #[command(subcommand)]
@@ -118,6 +137,24 @@ fn main() -> Result<()> {
         Some(Commands::Info { input }) => {
             info::info(input)?
         },
+        Some(Commands::IosPatch {
+                input,
+                output,
+                version,
+                slot,
+                no_shared,
+                enabled_patches
+             }
+        ) => {
+            title::iospatcher::patch_ios(
+                input,
+                output,
+                version,
+                slot,
+                no_shared,
+                enabled_patches,
+            )?
+        }
         Some(Commands::Lz77 { command }) => {
             match command {
                 archive::lz77::Commands::Compress { input, output } => {

src/bin/rustwii/nand/emunand.rs

@@ -1,7 +1,7 @@
 // nand/emunand.rs from ruswtii (c) 2025 NinjaCheetah & Contributors
 // https://github.com/NinjaCheetah/rustwii
 //
-// Code for EmuNAND-related commands in the rustii CLI.
+// Code for EmuNAND-related commands in the rustwii CLI.
 
 use std::{str, fs};
 use std::path::{absolute, Path};

src/bin/rustwii/nand/setting.rs

@@ -1,7 +1,7 @@
 // nand/setting.rs from ruswtii (c) 2025 NinjaCheetah & Contributors
 // https://github.com/NinjaCheetah/rustwii
 //
-// Code for setting.txt-related commands in the rustii CLI.
+// Code for setting.txt-related commands in the rustwii CLI.
 
 use std::{str, fs};
 use std::path::{Path, PathBuf};

src/bin/rustwii/title/fakesign.rs

@@ -1,7 +1,7 @@
 // title/fakesign.rs from ruswtii (c) 2025 NinjaCheetah & Contributors
 // https://github.com/NinjaCheetah/rustwii
 //
-// Code for the fakesign command in the rustii CLI.
+// Code for the fakesign command in the rustwii CLI.
 
 use std::{str, fs};
 use std::path::{Path, PathBuf};

src/bin/rustwii/title/iospatcher.rs

@@ -0,0 +1,129 @@
+// title/iospatcher.rs from ruswtii (c) 2025 NinjaCheetah & Contributors
+// https://github.com/NinjaCheetah/rustwii
+//
+// Code for the iospatcher command in the rustwii CLI.
+
+use std::fs;
+use std::path::{Path, PathBuf};
+use anyhow::{bail, Context, Result};
+use clap::Args;
+use rustwii::title;
+use rustwii::title::iospatcher;
+
+#[derive(Args)]
+#[clap(next_help_heading = "Patches")]
+#[group(multiple = true, required = true)]
+/// Modifications that can be made to a title, shared between the WAD and TMD commands.
+pub struct EnabledPatches {
+    /// Patch out signature checks
+    #[arg(long, action)]
+    sig_checks: bool,
+    /// Patch in access to ES_Identify
+    #[arg(long, action)]
+    es_identify: bool,
+    /// Patch in access to /dev/flash
+    #[arg(long, action)]
+    dev_flash: bool,
+    /// Patch out anti-downgrade checks
+    #[arg(long, action)]
+    allow_downgrade: bool,
+    /// Patch out drive inquiries (EXPERIMENTAL)
+    #[arg(long, action)]
+    drive_inquiry: bool,
+}
+
+pub fn patch_ios(
+    input: &str,
+    output: &Option<String>,
+    version: &Option<u16>,
+    slot: &Option<u8>,
+    no_shared: &bool,
+    enabled_patches: &EnabledPatches,
+) -> Result<()> {
+    let in_path = Path::new(input);
+    if !in_path.exists() {
+        bail!("Source WAD \"{}\" does not exist.", in_path.display());
+    }
+    let out_path = if output.is_some() {
+        PathBuf::from(output.clone().unwrap()).with_extension("wad")
+    } else {
+        in_path.to_path_buf()
+    };
+
+    let mut ios = title::Title::from_bytes(&fs::read(in_path)?).with_context(|| "The provided WAD file could not be parsed, and is likely invalid.")?;
+    let tid = hex::encode(ios.tmd.title_id());
+
+    // If the TID is not a valid IOS TID, then bail.
+    if !tid[..8].eq("00000001") || tid[8..].eq("00000001") || tid[8..].eq("00000002") {
+        bail!("The provided WAD does not appear to contain an IOS! No patches can be applied.")
+    }
+
+    let mut patches_applied = 0;
+
+    if let Some(version) = version {
+        ios.set_title_version(*version);
+        println!("Set new IOS version: {version}")
+    }
+
+    if let Some(slot) = slot && *slot >= 3 {
+        let tid = hex::decode(format!("00000001{slot:08X}"))?;
+        ios.set_title_id(tid.try_into().unwrap()).expect("Failed to set IOS slot!");
+        println!("Set new IOS slot: {slot}");
+    }
+
+    if enabled_patches.sig_checks ||
+        enabled_patches.es_identify ||
+        enabled_patches.dev_flash ||
+        enabled_patches.allow_downgrade
+    {
+        let es_index = iospatcher::ios_find_module(String::from("ES:"), &ios)
+            .with_context(|| "The ES module could not be found. This WAD is not a valid IOS.")?;
+        if enabled_patches.sig_checks {
+            print!("Applying signature check patch... ");
+            let count = iospatcher::ios_patch_sigchecks(&mut ios, es_index)?;
+            println!("{} patch(es) applied", count);
+            patches_applied += count;
+        }
+        if enabled_patches.es_identify {
+            print!("Applying ES_Identify access patch... ");
+            let count = iospatcher::ios_patch_es_identify(&mut ios, es_index)?;
+            println!("{} patch(es) applied", count);
+            patches_applied += count;
+        }
+        if enabled_patches.dev_flash {
+            print!("Applying /dev/flash access patch... ");
+            let count = iospatcher::ios_patch_dev_flash(&mut ios, es_index)?;
+            println!("{} patch(es) applied", count);
+            patches_applied += count;
+        }
+        if enabled_patches.allow_downgrade {
+            print!("Applying allow downgrading patch... ");
+            let count = iospatcher::ios_patch_allow_downgrade(&mut ios, es_index)?;
+            println!("{} patch(es) applied", count);
+            patches_applied += count;
+        }
+    }
+
+    if enabled_patches.drive_inquiry {
+        let dip_index = iospatcher::ios_find_module(String::from("DIP:"), &ios)
+            .with_context(|| "The DIP module could not be found. This WAD is not a valid IOS, \
+             or this IOS version does not use the DIP module.")?;
+        print!("Applying (EXPERIMENTAL) drive inquiry patch... ");
+        let count = iospatcher::ios_patch_drive_inquiry(&mut ios, dip_index)?;
+        println!("{} patch(es) applied", count);
+        patches_applied += count;
+    }
+
+    println!("\nTotal patches applied: {patches_applied}");
+
+    if patches_applied == 0 && version.is_none() && slot.is_none() {
+        bail!("No patchers were applied. Please make sure the specified patches are compatible \
+        with this IOS.")
+    }
+
+    ios.fakesign()?;
+    fs::write(out_path, ios.to_wad()?.to_bytes()?)?;
+
+    println!("IOS successfully patched!");
+    Ok(())
+}

src/bin/rustwii/title/mod.rs

@@ -6,3 +6,4 @@ pub mod nus;
 pub mod wad;
 pub mod tmd;
 mod shared;
+pub mod iospatcher;

src/bin/rustwii/title/nus.rs

@@ -1,7 +1,7 @@
 // title/nus.rs from ruswtii (c) 2025 NinjaCheetah & Contributors
 // https://github.com/NinjaCheetah/rustwii
 //
-// Code for NUS-related commands in the rustii CLI.
+// Code for NUS-related commands in the rustwii CLI.
 
 use std::{str, fs};
 use std::path::PathBuf;

src/bin/rustwii/title/shared.rs

@@ -1,7 +1,7 @@
 // title/shared.rs from ruswtii (c) 2025 NinjaCheetah & Contributors
 // https://github.com/NinjaCheetah/rustwii
 //
-// Code shared between title commands in the rustii CLI.
+// Code shared between title commands in the rustwii CLI.
 
 use anyhow::bail;
 use clap::Args;

src/bin/rustwii/title/tmd.rs

@@ -1,7 +1,7 @@
 // title/tmd.rs from ruswtii (c) 2025 NinjaCheetah & Contributors
 // https://github.com/NinjaCheetah/rustwii
 //
-// Code for TMD-related commands in the rustii CLI.
+// Code for TMD-related commands in the rustwii CLI.
 
 use std::{str, fs};
 use std::path::{Path, PathBuf};

src/bin/rustwii/title/wad.rs

@@ -1,7 +1,7 @@
 // title/wad.rs from ruswtii (c) 2025 NinjaCheetah & Contributors
 // https://github.com/NinjaCheetah/rustwii
 //
-// Code for WAD-related commands in the rustii CLI.
+// Code for WAD-related commands in the rustwii CLI.
 
 use std::{str, fs, fmt};
 use std::path::{Path, PathBuf};

src/title/iospatcher.rs

@@ -0,0 +1,136 @@
+// title/iospatcher.rs from ruswtii (c) 2025 NinjaCheetah & Contributors
+// https://github.com/NinjaCheetah/rustwii
+//
+// Module for applying patches to IOSes using a Title.
+
+use std::io::{Cursor, Seek, SeekFrom, Write};
+use thiserror::Error;
+use crate::title;
+use crate::title::content;
+
+#[derive(Debug, Error)]
+pub enum IOSPatcherError {
+    #[error("this title is not an IOS")]
+    NotIOS,
+    #[error("the required module \"{0}\" could not be found, this may not be a valid IOS")]
+    ModuleNotFound(String),
+    #[error("failed to get IOS content")]
+    Content(#[from] content::ContentError),
+    #[error("failed to set content in Title")]
+    Title(#[from] title::TitleError),
+    #[error("IOS content is invalid")]
+    IO(#[from] std::io::Error),
+}
+
+pub fn ios_find_module(module_keyword: String, ios: &title::Title) -> Result<usize, IOSPatcherError> {
+    let content_records = ios.tmd.content_records();
+    let tid = hex::encode(ios.tmd.title_id());
+
+    // If the TID is not a valid IOS TID, then return NotIOS. It's possible that this could catch
+    // some modified IOSes that currently have a non-IOS TID but that's weird and if you're doing
+    // that please stop.
+    if !tid[..8].eq("00000001") || tid[8..].eq("00000001") || tid[8..].eq("00000002") {
+        return Err(IOSPatcherError::NotIOS);
+    }
+
+    // Find the module's keyword in the content, and return the (true) index of the content that
+    // it was found in.
+    let keyword = module_keyword.as_bytes();
+    for record in content_records {
+        let content_decrypted = ios.get_content_by_index(record.index as usize)?;
+        let offset = content_decrypted
+            .windows(keyword.len())
+            .position(|window| window == keyword);
+        if offset.is_some() {
+            return Ok(record.index as usize);
+        }
+    }
+
+    // If we didn't return early by finding the offset, then return a ModuleNotFound error.
+    Err(IOSPatcherError::ModuleNotFound(module_keyword))
+}
+
+fn ios_apply_patches(
+    target_content: &mut Cursor<Vec<u8>>,
+    find_seq: Vec<Vec<u8>>,
+    replace_seq: Vec<Vec<u8>>
+) -> Result<i32, IOSPatcherError> {
+    let mut patch_count = 0;
+    for idx in 0..find_seq.len() {
+        let offset = target_content.get_ref()
+            .windows(find_seq[idx].len())
+            .position(|window| window == find_seq[idx]);
+        if let Some(offset) = offset {
+            target_content.seek(SeekFrom::Start(offset as u64))?;
+            target_content.write_all(&replace_seq[idx])?;
+            patch_count += 1;
+        }
+    }
+
+    Ok(patch_count)
+}
+
+pub fn ios_patch_sigchecks(ios: &mut title::Title, es_index: usize) -> Result<i32, IOSPatcherError> {
+    let target_content = ios.get_content_by_index(es_index)?;
+    let mut buf = Cursor::new(target_content);
+
+    let find_seq = vec![vec![0x20, 0x07, 0x23, 0xa2], vec![0x20, 0x07, 0x4b, 0x0b]];
+    let replace_seq: Vec<Vec<u8>> = vec![vec![0x20, 0x00, 0x23, 0xa2], vec![0x20, 0x00, 0x4b, 0x0b]];
+    let patch_count = ios_apply_patches(&mut buf, find_seq, replace_seq)?;
+
+    ios.set_content(buf.get_ref(), es_index, None, None)?;
+
+    Ok(patch_count)
+}
+
+pub fn ios_patch_es_identify(ios: &mut title::Title, es_index: usize) -> Result<i32, IOSPatcherError> {
+    let target_content = ios.get_content_by_index(es_index)?;
+    let mut buf = Cursor::new(target_content);
+
+    let find_seq = vec![vec![0x28, 0x03, 0xd1, 0x23]];
+    let replace_seq = vec![vec![0x28, 0x03, 0x00, 0x00]];
+    let patch_count = ios_apply_patches(&mut buf, find_seq, replace_seq)?;
+
+    ios.set_content(buf.get_ref(), es_index, None, None)?;
+
+    Ok(patch_count)
+}
+
+pub fn ios_patch_dev_flash(ios: &mut title::Title, es_index: usize) -> Result<i32, IOSPatcherError> {
+    let target_content = ios.get_content_by_index(es_index)?;
+    let mut buf = Cursor::new(target_content);
+
+    let find_seq = vec![vec![0x42, 0x8b, 0xd0, 0x01, 0x25, 0x66]];
+    let replace_seq = vec![vec![0x42, 0x8b, 0xe0, 0x01, 0x25, 0x66]];
+    let patch_count = ios_apply_patches(&mut buf, find_seq, replace_seq)?;
+
+    ios.set_content(buf.get_ref(), es_index, None, None)?;
+
+    Ok(patch_count)
+}
+
+pub fn ios_patch_allow_downgrade(ios: &mut title::Title, es_index: usize) -> Result<i32, IOSPatcherError> {
+    let target_content = ios.get_content_by_index(es_index)?;
+    let mut buf = Cursor::new(target_content);
+
+    let find_seq = vec![vec![0xd2, 0x01, 0x4e, 0x56]];
+    let replace_seq = vec![vec![0xe0, 0x01, 0x4e, 0x56]];
+    let patch_count = ios_apply_patches(&mut buf, find_seq, replace_seq)?;
+
+    ios.set_content(buf.get_ref(), es_index, None, None)?;
+
+    Ok(patch_count)
+}
+
+pub fn ios_patch_drive_inquiry(ios: &mut title::Title, dip_index: usize) -> Result<i32, IOSPatcherError> {
+    let target_content = ios.get_content_by_index(dip_index)?;
+    let mut buf = Cursor::new(target_content);
+
+    let find_seq = vec![vec![0x49, 0x4c, 0x23, 0x90, 0x68, 0x0a]];
+    let replace_seq = vec![vec![0x20, 0x00, 0xe5, 0x38, 0x68, 0x0a]];
+    let patch_count = ios_apply_patches(&mut buf, find_seq, replace_seq)?;
+
+    ios.set_content(buf.get_ref(), dip_index, None, None)?;
+
+    Ok(patch_count)
+}

src/title/mod.rs

@@ -7,6 +7,7 @@ pub mod cert;
 pub mod commonkeys;
 pub mod content;
 pub mod crypto;
+pub mod iospatcher;
 pub mod nus;
 pub mod ticket;
 pub mod tmd;
@@ -137,6 +138,7 @@ impl Title {
     /// content type can be provided, with the existing values being preserved by default.
     pub fn set_content(&mut self, content: &[u8], index: usize, cid: Option<u32>, content_type: Option<tmd::ContentType>) -> Result<(), TitleError> {
         self.content.set_content(content, index, cid, content_type, self.ticket.title_key_dec())?;
+        self.tmd.set_content_records(self.content.content_records());
         Ok(())
     }
 
@@ -146,6 +148,7 @@ impl Title {
     /// content records.
     pub fn add_content(&mut self, content: &[u8], cid: u32, content_type: tmd::ContentType) -> Result<(), TitleError> {
         self.content.add_content(content, cid, content_type, self.ticket.title_key_dec())?;
+        self.tmd.set_content_records(self.content.content_records());
         Ok(())
     }
     
@@ -195,6 +198,11 @@ impl Title {
         Ok(())
     }
 
+    pub fn set_title_version(&mut self, version: u16) {
+        self.tmd.set_title_version(version);
+        self.ticket.set_title_version(version);
+    }
+
     pub fn set_cert_chain(&mut self, cert_chain: cert::CertificateChain) {
         self.cert_chain = cert_chain;
     }

src/title/ticket.rs

@@ -212,6 +212,10 @@ impl Ticket {
     pub fn title_version(&self) -> u16 {
         self.title_version
     }
+    
+    pub fn set_title_version(&mut self, version: u16) {
+        self.title_version = version;
+    }
 
     /// Gets the permitted titles mask listed in the Ticket.
     pub fn permitted_titles_mask(&self) -> [u8; 4] {

src/title/tmd.rs

@@ -393,6 +393,10 @@ impl TMD {
         self.title_type = new_type;
         Ok(())
     }
+    
+    pub fn set_title_version(&mut self, version: u16) {
+        self.title_version = version;
+    }
 
     /// Gets the type of content described by a content record in a TMD.
     pub fn content_type(&self, index: usize) -> ContentType {