rnicro 0.1.0

A Linux x86_64 debugger and exploit development toolkit written in Rust
Documentation
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#[cfg(not(target_os = "linux"))]
fn main() {
    eprintln!("rnicro requires Linux (ptrace). This binary was built for a non-Linux target.");
    std::process::exit(1);
}

#[cfg(target_os = "linux")]
fn main() -> anyhow::Result<()> {
    linux::run()
}

#[cfg(target_os = "linux")]
mod linux {
    use std::path::PathBuf;

    use clap::Parser;
    use colored::Colorize;
    use rustyline::DefaultEditor;

    use rnicro::disasm::{self, DisasmStyle};
    use rnicro::target::Target;
    use rnicro::types::{ProcessState, StopReason, VirtAddr};

    #[derive(Parser)]
    #[command(name = "rnicro", about = "A Linux x86_64 debugger & exploit development toolkit")]
    struct Cli {
        /// Program to debug
        program: Option<PathBuf>,

        /// Attach to a running process by PID
        #[arg(short = 'p', long = "attach")]
        attach_pid: Option<i32>,

        /// Run as DAP (Debug Adapter Protocol) server on stdin/stdout
        #[arg(long)]
        dap: bool,

        /// Arguments to pass to the program
        #[arg(trailing_var_arg = true)]
        args: Vec<String>,
    }

    pub fn run() -> anyhow::Result<()> {
        let cli = Cli::parse();

        if cli.dap {
            let mut dap = rnicro::dap_server::DapServer::new_stdio();
            dap.run()?;
            return Ok(());
        }

        let mut target = if let Some(pid) = cli.attach_pid {
            let pid = nix::unistd::Pid::from_raw(pid);
            let t = Target::attach(pid)?;
            println!(
                "{} attached to process {}",
                "rnicro".bold().cyan(),
                pid,
            );
            t
        } else if let Some(ref program) = cli.program {
            let args_ref: Vec<&str> = cli.args.iter().map(|s| s.as_str()).collect();
            let t = Target::launch(program, &args_ref)?;
            println!(
                "{} launched process {} ({})",
                "rnicro".bold().cyan(),
                t.pid(),
                program.display()
            );
            t
        } else {
            eprintln!("error: provide a program to debug or use --attach <pid>");
            std::process::exit(1);
        };

        if target.has_debug_info() {
            println!("  debug info: {}", "available".green());
        } else {
            println!("  debug info: {}", "not found (stripped binary)".yellow());
        }

        let mut rl = DefaultEditor::new()?;

        loop {
            if target.state() == ProcessState::Exited
                || target.state() == ProcessState::Terminated
            {
                println!("{}", "Process has ended.".yellow());
                break;
            }

            let prompt = format!("{} ", "rnicro>".bold().green());
            let line = match rl.readline(&prompt) {
                Ok(line) => line,
                Err(
                    rustyline::error::ReadlineError::Interrupted
                    | rustyline::error::ReadlineError::Eof,
                ) => {
                    break;
                }
                Err(e) => {
                    eprintln!("readline error: {}", e);
                    break;
                }
            };

            let line = line.trim();
            if line.is_empty() {
                continue;
            }
            rl.add_history_entry(line)?;

            let parts: Vec<&str> = line.split_whitespace().collect();
            let cmd = parts[0];
            let args = &parts[1..];

            if let Err(e) = handle_command(&mut target, cmd, args) {
                eprintln!("{}: {}", "error".red(), e);
            }
        }

        Ok(())
    }

    fn handle_command(target: &mut Target, cmd: &str, args: &[&str]) -> anyhow::Result<()> {
        match cmd {
            "continue" | "c" => cmd_continue(target),
            "stepi" | "si" => cmd_stepi(target),
            "step" | "s" => cmd_step(target),
            "next" | "n" => cmd_next(target),
            "finish" | "fin" => cmd_finish(target),
            "register" | "reg" | "r" => cmd_register(target, args),
            "breakpoint" | "break" | "b" => cmd_breakpoint(target, args),
            "memory" | "mem" | "x" => cmd_memory(target, args),
            "disassemble" | "disas" | "d" => cmd_disassemble(target, args),
            "backtrace" | "bt" => cmd_backtrace(target),
            "watchpoint" | "watch" | "wp" => cmd_watchpoint(target, args),
            "catchpoint" | "catch" => cmd_catchpoint(target, args),
            "signal" | "sig" => cmd_signal(target, args),
            "print" | "p" => cmd_print(target, args),
            "locals" => cmd_locals(target),
            "info" if args.first() == Some(&"locals") => cmd_locals(target),
            "threads" | "thr" => cmd_threads(target),
            "thread" | "t" => cmd_thread(target, args),
            "libs" | "sharedlib" => cmd_libs(target),
            "checksec" => cmd_checksec(target),
            "got" | "plt" => cmd_got(target, args),
            "strings" | "str" => cmd_strings(target, args),
            "gadgets" | "rop" => cmd_gadgets(target, args),
            "entropy" => cmd_entropy(target),
            "pattern" | "pat" => cmd_pattern(args),
            "patch" => cmd_patch(target, args),
            "patch-file" => cmd_patch_file(target, args),
            "antidebug" | "antid" => cmd_antidebug(target, args),
            "heap" => cmd_heap(target, args),
            "coredump" | "core" => cmd_coredump(target, args),
            "strace" => cmd_strace(target, args),
            "scan" | "search" => cmd_scan(target, args),
            "hook" => cmd_hook(target, args),
            "fmtstr" | "fmt" => cmd_fmtstr(args),
            "shellcode" | "sc" => cmd_shellcode(args),
            "sigrop" | "srop" => cmd_sigrop(args),
            "list" | "l" => cmd_list(target),
            "help" | "h" => cmd_help(),
            "quit" | "q" => std::process::exit(0),
            _ => {
                println!(
                    "unknown command: {}. Type 'help' for available commands.",
                    cmd
                );
                Ok(())
            }
        }
    }

    fn cmd_continue(target: &mut Target) -> anyhow::Result<()> {
        let reason = target.resume()?;
        print_stop_reason(&reason);
        print_thread_info(target);
        print_location(target);
        Ok(())
    }

    fn cmd_stepi(target: &mut Target) -> anyhow::Result<()> {
        let reason = target.step_instruction()?;
        print_stop_reason(&reason);
        let regs = target.read_registers()?;
        println!("  rip = {}", format!("0x{:016x}", regs.pc()).cyan());
        print_location(target);
        Ok(())
    }

    fn cmd_step(target: &mut Target) -> anyhow::Result<()> {
        let reason = target.step_in()?;
        print_stop_reason(&reason);
        let regs = target.read_registers()?;
        println!("  rip = {}", format!("0x{:016x}", regs.pc()).cyan());
        print_location(target);
        Ok(())
    }

    fn cmd_next(target: &mut Target) -> anyhow::Result<()> {
        let reason = target.step_over()?;
        print_stop_reason(&reason);
        let regs = target.read_registers()?;
        println!("  rip = {}", format!("0x{:016x}", regs.pc()).cyan());
        print_location(target);
        Ok(())
    }

    fn cmd_finish(target: &mut Target) -> anyhow::Result<()> {
        let reason = target.step_out()?;
        print_stop_reason(&reason);
        let regs = target.read_registers()?;
        println!("  rip = {}", format!("0x{:016x}", regs.pc()).cyan());
        print_location(target);
        Ok(())
    }

    fn cmd_register(target: &mut Target, args: &[&str]) -> anyhow::Result<()> {
        match args.first().copied() {
            Some("read") | Some("r") | None => {
                let regs = target.read_registers()?;
                for (name, value) in regs.iter() {
                    println!(
                        "  {:>8} = {}",
                        name.bold(),
                        format!("0x{:016x}", value).cyan()
                    );
                }
            }
            Some("write") | Some("w") => {
                if args.len() < 3 {
                    println!("usage: register write <name> <value>");
                    return Ok(());
                }
                let name = args[1];
                let value = parse_address(args[2])?;
                let mut regs = target.read_registers()?;
                regs.set(name, value)?;
                target.write_registers(&regs)?;
                println!(
                    "  {} = {}",
                    name.bold(),
                    format!("0x{:016x}", value).cyan()
                );
            }
            Some(sub) => {
                println!("unknown register subcommand: {}", sub);
            }
        }
        Ok(())
    }

    fn cmd_breakpoint(target: &mut Target, args: &[&str]) -> anyhow::Result<()> {
        match args.first().copied() {
            Some("set") | Some("s") => {
                if args.len() < 2 {
                    println!("usage: breakpoint set <address|symbol> [if <condition>]");
                    return Ok(());
                }
                let addr = resolve_address(target, args[1])?;

                // Check for "if <condition>" syntax
                let condition = if args.len() >= 4 && args[2] == "if" {
                    Some(args[3..].join(" "))
                } else {
                    None
                };

                let id = if let Some(cond) = &condition {
                    target.set_conditional_breakpoint(addr, cond.clone())?
                } else {
                    target.set_breakpoint(addr)?
                };

                if let Some(cond) = &condition {
                    println!("  breakpoint #{} set at {} if {}", id, addr, cond);
                } else {
                    println!("  breakpoint #{} set at {}", id, addr);
                }
            }
            Some("delete") | Some("d") => {
                if args.len() < 2 {
                    println!("usage: breakpoint delete <address>");
                    return Ok(());
                }
                let addr = VirtAddr(parse_address(args[1])?);
                target.remove_breakpoint(addr)?;
                println!("  breakpoint at {} removed", addr);
            }
            Some("list") | Some("l") | None => {
                let bps = target.list_breakpoints();
                if bps.is_empty() {
                    println!("  no breakpoints set");
                } else {
                    for (i, (addr, cond)) in bps.iter().enumerate() {
                        if let Some(cond) = cond {
                            println!("  #{}: {} if {}", i + 1, addr, cond);
                        } else {
                            println!("  #{}: {}", i + 1, addr);
                        }
                    }
                }
            }
            Some(sub) => {
                println!("unknown breakpoint subcommand: {}", sub);
            }
        }
        Ok(())
    }

    fn cmd_memory(target: &mut Target, args: &[&str]) -> anyhow::Result<()> {
        if args.is_empty() {
            println!("usage: memory read <address> [length]");
            println!("       memory write <address> <hex_bytes>");
            println!("       memory maps");
            return Ok(());
        }

        match args[0] {
            "read" | "r" => {
                if args.len() < 2 {
                    println!("usage: memory read <address> [length]");
                    return Ok(());
                }
                let addr = VirtAddr(parse_address(args[1])?);
                let len: usize = args.get(2).and_then(|s| s.parse().ok()).unwrap_or(64);
                let data = target.read_memory(addr, len)?;
                print_hexdump(addr, &data);
            }
            "write" | "w" => {
                if args.len() < 3 {
                    println!("usage: memory write <address> <hex_bytes>");
                    println!("  hex_bytes: continuous hex string, e.g. 90909090 or cc");
                    return Ok(());
                }
                let addr = VirtAddr(parse_address(args[1])?);
                let hex_str: String = args[2..].join("");
                let bytes = parse_hex_bytes(&hex_str)?;
                target.write_memory(addr, &bytes)?;
                println!(
                    "  wrote {} byte(s) at {}",
                    bytes.len(),
                    format!("0x{:x}", addr.addr()).cyan()
                );
            }
            "maps" | "m" => {
                let maps = target.memory_maps()?;
                println!(
                    "  {:>18} {:>18}  {}  {}",
                    "start".bold(),
                    "end".bold(),
                    "perm".bold(),
                    "pathname".bold()
                );
                for region in &maps {
                    println!(
                        "  {:018x} {:018x}  {}  {}",
                        region.start.addr(),
                        region.end.addr(),
                        region.perms,
                        region.pathname,
                    );
                }
            }
            sub => {
                println!("unknown memory subcommand: {}", sub);
            }
        }
        Ok(())
    }

    fn cmd_disassemble(target: &mut Target, args: &[&str]) -> anyhow::Result<()> {
        let count: usize = args
            .iter()
            .find(|a| a.starts_with("-c"))
            .and_then(|_| args.iter().find_map(|a| a.parse().ok()))
            .unwrap_or(10);

        let style = if args.contains(&"--att") || args.contains(&"--gas") {
            DisasmStyle::Gas
        } else {
            DisasmStyle::Intel
        };

        let insns = if let Some(addr_str) = args.first().filter(|a| !a.starts_with('-')) {
            let addr = VirtAddr(parse_address(addr_str)?);
            target.disassemble(addr, count, style)?
        } else {
            target.disassemble_at_pc(count, style)?
        };

        print!("{}", disasm::format_disassembly(&insns));
        Ok(())
    }

    fn cmd_watchpoint(target: &mut Target, args: &[&str]) -> anyhow::Result<()> {
        use rnicro::watchpoint::{WatchpointSize, WatchpointType};

        match args.first().copied() {
            Some("set") | Some("s") => {
                if args.len() < 4 {
                    println!("usage: watchpoint set <address> <write|rw|execute> <size>");
                    println!("  size: 1, 2, 4, or 8 bytes");
                    return Ok(());
                }
                let addr = resolve_address(target, args[1])?;
                let wp_type = match args[2] {
                    "write" | "w" => WatchpointType::Write,
                    "rw" | "readwrite" => WatchpointType::ReadWrite,
                    "execute" | "exec" | "x" => WatchpointType::Execute,
                    other => {
                        println!("unknown watchpoint type: {} (use write|rw|execute)", other);
                        return Ok(());
                    }
                };
                let size_val: usize = args[3].parse().map_err(|_| {
                    anyhow::anyhow!("invalid size: {} (use 1, 2, 4, or 8)", args[3])
                })?;
                let size = WatchpointSize::from_bytes(size_val).ok_or_else(|| {
                    anyhow::anyhow!("invalid size: {} (must be 1, 2, 4, or 8)", size_val)
                })?;
                let id = target.set_watchpoint(addr, wp_type, size)?;
                println!(
                    "  watchpoint #{} set at {} ({}, {} bytes)",
                    id, addr, wp_type, size
                );
            }
            Some("delete") | Some("d") => {
                if args.len() < 2 {
                    println!("usage: watchpoint delete <id>");
                    return Ok(());
                }
                let id: u32 = args[1]
                    .parse()
                    .map_err(|_| anyhow::anyhow!("invalid id: {}", args[1]))?;
                target.remove_watchpoint(id)?;
                println!("  watchpoint #{} removed", id);
            }
            Some("list") | Some("l") | None => {
                let wps = target.list_watchpoints();
                if wps.is_empty() {
                    println!("  no watchpoints set");
                } else {
                    for wp in &wps {
                        println!(
                            "  #{}: {} ({}, {} bytes) [slot {}]",
                            wp.id, wp.addr, wp.wp_type, wp.size, wp.slot
                        );
                    }
                }
            }
            Some(sub) => {
                println!("unknown watchpoint subcommand: {}", sub);
            }
        }
        Ok(())
    }

    fn cmd_catchpoint(target: &mut Target, args: &[&str]) -> anyhow::Result<()> {
        match args.first().copied() {
            Some("syscall") | Some("sys") => {
                match args.get(1).copied() {
                    Some("add") | Some("a") => {
                        if args.len() < 3 {
                            println!("usage: catchpoint syscall add <name|number|all>");
                            return Ok(());
                        }
                        if args[2] == "all" {
                            target.set_catch_all_syscalls(true);
                            println!("  catching all syscalls");
                        } else if let Some(num) = rnicro::syscall::number(args[2]) {
                            target.catch_syscall(num);
                            println!("  catching syscall {} ({})", args[2], num);
                        } else if let Ok(num) = args[2].parse::<u64>() {
                            target.catch_syscall(num);
                            let name = rnicro::syscall::name(num).unwrap_or("unknown");
                            println!("  catching syscall {} ({})", name, num);
                        } else {
                            println!("unknown syscall: {}", args[2]);
                        }
                    }
                    Some("remove") | Some("r") => {
                        if args.len() < 3 {
                            println!("usage: catchpoint syscall remove <name|number|all>");
                            return Ok(());
                        }
                        if args[2] == "all" {
                            target.set_catch_all_syscalls(false);
                            println!("  stopped catching all syscalls");
                        } else if let Some(num) = rnicro::syscall::number(args[2]) {
                            target.uncatch_syscall(num);
                            println!("  removed catchpoint for syscall {}", args[2]);
                        } else if let Ok(num) = args[2].parse::<u64>() {
                            target.uncatch_syscall(num);
                            println!("  removed catchpoint for syscall {}", num);
                        }
                    }
                    Some("list") | Some("l") | None => {
                        if target.is_catching_syscalls() {
                            let caught = target.caught_syscalls();
                            if caught.is_empty() {
                                println!("  catching: all syscalls");
                            } else {
                                println!("  caught syscalls:");
                                for &num in caught {
                                    let name = rnicro::syscall::name(num).unwrap_or("unknown");
                                    println!("    {} ({})", name, num);
                                }
                            }
                        } else {
                            println!("  no syscall catchpoints set");
                        }
                    }
                    Some(sub) => println!("unknown catchpoint syscall subcommand: {}", sub),
                }
            }
            None => {
                println!("usage: catchpoint syscall add|remove|list ...");
            }
            Some(sub) => println!("unknown catchpoint type: {}", sub),
        }
        Ok(())
    }

    fn cmd_signal(target: &mut Target, args: &[&str]) -> anyhow::Result<()> {
        use nix::sys::signal::Signal;

        match args.first().copied() {
            Some("handle") | Some("h") => {
                if args.len() < 3 {
                    println!("usage: signal handle <signal> stop|nostop|pass|nopass");
                    return Ok(());
                }
                let sig = parse_signal(args[1])?;
                let mut policy = target.signal_policy(sig);
                for &action in &args[2..] {
                    match action {
                        "stop" => policy.stop = true,
                        "nostop" => policy.stop = false,
                        "pass" => policy.pass = true,
                        "nopass" => policy.pass = false,
                        other => {
                            println!("unknown action: {} (use stop|nostop|pass|nopass)", other);
                            return Ok(());
                        }
                    }
                }
                target.set_signal_policy(sig, policy);
                println!(
                    "  {:?}: stop={}, pass={}",
                    sig, policy.stop, policy.pass
                );
            }
            Some("list") | Some("l") | None => {
                println!("  {:>15}  {}  {}", "signal".bold(), "stop".bold(), "pass".bold());
                let signals = [
                    Signal::SIGHUP, Signal::SIGINT, Signal::SIGQUIT,
                    Signal::SIGILL, Signal::SIGTRAP, Signal::SIGABRT,
                    Signal::SIGBUS, Signal::SIGFPE, Signal::SIGKILL,
                    Signal::SIGUSR1, Signal::SIGSEGV, Signal::SIGUSR2,
                    Signal::SIGPIPE, Signal::SIGALRM, Signal::SIGTERM,
                    Signal::SIGCHLD, Signal::SIGCONT, Signal::SIGSTOP,
                    Signal::SIGTSTP, Signal::SIGTTIN, Signal::SIGTTOU,
                ];
                for sig in &signals {
                    let policy = target.signal_policy(*sig);
                    println!(
                        "  {:>15}  {:<5}  {}",
                        format!("{:?}", sig),
                        if policy.stop { "yes" } else { "no" },
                        if policy.pass { "yes" } else { "no" },
                    );
                }
            }
            Some(sub) => println!("unknown signal subcommand: {}", sub),
        }
        Ok(())
    }

    fn parse_signal(s: &str) -> anyhow::Result<nix::sys::signal::Signal> {
        use nix::sys::signal::Signal;
        let s_upper = s.to_uppercase();
        let name = if s_upper.starts_with("SIG") {
            s_upper.clone()
        } else {
            format!("SIG{}", s_upper)
        };
        match name.as_str() {
            "SIGHUP" => Ok(Signal::SIGHUP),
            "SIGINT" => Ok(Signal::SIGINT),
            "SIGQUIT" => Ok(Signal::SIGQUIT),
            "SIGILL" => Ok(Signal::SIGILL),
            "SIGTRAP" => Ok(Signal::SIGTRAP),
            "SIGABRT" => Ok(Signal::SIGABRT),
            "SIGBUS" => Ok(Signal::SIGBUS),
            "SIGFPE" => Ok(Signal::SIGFPE),
            "SIGKILL" => Ok(Signal::SIGKILL),
            "SIGUSR1" => Ok(Signal::SIGUSR1),
            "SIGSEGV" => Ok(Signal::SIGSEGV),
            "SIGUSR2" => Ok(Signal::SIGUSR2),
            "SIGPIPE" => Ok(Signal::SIGPIPE),
            "SIGALRM" => Ok(Signal::SIGALRM),
            "SIGTERM" => Ok(Signal::SIGTERM),
            "SIGCHLD" => Ok(Signal::SIGCHLD),
            "SIGCONT" => Ok(Signal::SIGCONT),
            "SIGSTOP" => Ok(Signal::SIGSTOP),
            "SIGTSTP" => Ok(Signal::SIGTSTP),
            "SIGTTIN" => Ok(Signal::SIGTTIN),
            "SIGTTOU" => Ok(Signal::SIGTTOU),
            _ => Err(anyhow::anyhow!("unknown signal: {}", s)),
        }
    }

    fn cmd_backtrace(target: &mut Target) -> anyhow::Result<()> {
        match target.backtrace() {
            Ok(frames) => {
                for frame in &frames {
                    print!("  #{:<3} {}", frame.index, format!("0x{:016x}", frame.pc.addr()).cyan());
                    if let Some(func) = &frame.function {
                        print!(" in {}", func.bold());
                    }
                    if let Some(loc) = &frame.location {
                        print!(" at {}", loc);
                    }
                    println!();
                }
                if frames.is_empty() {
                    println!("  {}", "empty backtrace".yellow());
                }
            }
            Err(e) => {
                // Fallback: show at least the current PC
                let regs = target.read_registers()?;
                println!("  #0   {} (unwind failed: {})", format!("0x{:016x}", regs.pc()).cyan(), e);
            }
        }
        Ok(())
    }

    fn cmd_print(target: &mut Target, args: &[&str]) -> anyhow::Result<()> {
        if args.is_empty() {
            println!("usage: print <variable_name>");
            return Ok(());
        }
        let name = args[0];
        match target.read_variable(name) {
            Ok(Some((var, formatted))) => {
                println!(
                    "  {} ({}) = {}",
                    var.name.bold(),
                    var.type_info.name.dimmed(),
                    formatted.cyan()
                );
            }
            Ok(None) => {
                println!("  variable '{}' not found at current PC", name);
            }
            Err(e) => {
                println!("  {}: {}", "error".red(), e);
            }
        }
        Ok(())
    }

    fn cmd_locals(target: &mut Target) -> anyhow::Result<()> {
        match target.list_variables() {
            Ok(vars) => {
                if vars.is_empty() {
                    println!("  {}", "no local variables in scope".yellow());
                } else {
                    for var in &vars {
                        // Try to read each variable's value
                        match target.read_variable(&var.name) {
                            Ok(Some((_, formatted))) => {
                                println!(
                                    "  {} ({}) = {}",
                                    var.name.bold(),
                                    var.type_info.name.dimmed(),
                                    formatted.cyan()
                                );
                            }
                            _ => {
                                println!(
                                    "  {} ({}) = {}",
                                    var.name.bold(),
                                    var.type_info.name.dimmed(),
                                    "<unavailable>".dimmed()
                                );
                            }
                        }
                    }
                }
            }
            Err(e) => {
                println!("  {}: {}", "error".red(), e);
            }
        }
        Ok(())
    }

    fn cmd_threads(target: &mut Target) -> anyhow::Result<()> {
        let threads = target.thread_list();
        let current = target.current_tid();
        println!("  {} thread(s):", threads.len());
        for &tid in threads {
            let marker = if tid == current { "*" } else { " " };
            let label = if tid == target.pid() {
                " (main)".dimmed().to_string()
            } else {
                String::new()
            };
            println!("  {} tid {}{}", marker.green().bold(), tid, label);
        }
        Ok(())
    }

    fn cmd_thread(target: &mut Target, args: &[&str]) -> anyhow::Result<()> {
        if args.is_empty() {
            println!("  current thread: tid {}", target.current_tid());
            return Ok(());
        }
        let tid: i32 = args[0]
            .parse()
            .map_err(|_| anyhow::anyhow!("invalid tid: {}", args[0]))?;
        target.switch_thread(nix::unistd::Pid::from_raw(tid))?;
        println!("  switched to thread tid {}", tid);
        Ok(())
    }

    fn cmd_libs(target: &mut Target) -> anyhow::Result<()> {
        match target.shared_libraries() {
            Ok(libs) => {
                println!("  {:>18}  {}", "base address".bold(), "library".bold());
                for lib in &libs {
                    let display_name = if lib.name.is_empty() {
                        "<main executable>".dimmed().to_string()
                    } else {
                        lib.name.clone()
                    };
                    println!(
                        "  {:018x}  {}",
                        lib.base_addr, display_name
                    );
                }
                if libs.is_empty() {
                    println!("  {}", "no shared libraries found (statically linked?)".yellow());
                }
            }
            Err(e) => {
                println!(
                    "  {}: {} (try running 'memory maps' as fallback)",
                    "could not read link_map".yellow(),
                    e
                );
            }
        }
        Ok(())
    }

    fn cmd_list(target: &mut Target) -> anyhow::Result<()> {
        if let Ok(Some(loc)) = target.source_location() {
            println!(
                "  {} {}:{}",
                "at".dimmed(),
                loc.file.bold(),
                loc.line.to_string().bold()
            );
            // Try to read and display the source file
            if let Ok(content) = std::fs::read_to_string(&loc.file) {
                let lines: Vec<&str> = content.lines().collect();
                let line_idx = loc.line as usize;
                let start = line_idx.saturating_sub(4);
                let end = (line_idx + 3).min(lines.len());
                for i in start..end {
                    let marker = if i + 1 == line_idx { ">" } else { " " };
                    let line_num = format!("{:4}", i + 1);
                    if i + 1 == line_idx {
                        println!("  {} {} {}", marker.green().bold(), line_num.green(), lines[i]);
                    } else {
                        println!("  {} {} {}", marker, line_num.dimmed(), lines[i]);
                    }
                }
            }
        } else {
            println!("  {}", "no source information available".yellow());
        }
        if let Ok(Some(func)) = target.current_function() {
            println!("  in {}", func.cyan());
        }
        Ok(())
    }

    fn cmd_checksec(target: &mut Target) -> anyhow::Result<()> {
        use rnicro::checksec::SecurityStatus;

        let result = target.checksec()?;
        println!("  {}", "Security mechanisms:".bold());
        println!(
            "  {:>12}: {}",
            "RELRO".bold(),
            match result.relro {
                SecurityStatus::Full => "Full RELRO".green().to_string(),
                SecurityStatus::Partial => "Partial RELRO".yellow().to_string(),
                SecurityStatus::None => "No RELRO".red().to_string(),
            }
        );
        println!(
            "  {:>12}: {}",
            "Stack canary".bold(),
            if result.canary {
                "Found".green().to_string()
            } else {
                "Not found".red().to_string()
            }
        );
        println!(
            "  {:>12}: {}",
            "NX".bold(),
            if result.nx {
                "Enabled".green().to_string()
            } else {
                "Disabled".red().to_string()
            }
        );
        println!(
            "  {:>12}: {}",
            "PIE".bold(),
            if result.pie {
                "Enabled".green().to_string()
            } else {
                "Disabled".yellow().to_string()
            }
        );
        println!(
            "  {:>12}: {}",
            "FORTIFY".bold(),
            if result.fortify {
                "Enabled".green().to_string()
            } else {
                "Not found".yellow().to_string()
            }
        );
        if result.rpath {
            println!(
                "  {:>12}: {}",
                "RPATH".bold(),
                "Present (potential hijack vector)".yellow()
            );
        }
        if result.runpath {
            println!(
                "  {:>12}: {}",
                "RUNPATH".bold(),
                "Present (potential hijack vector)".yellow()
            );
        }
        Ok(())
    }

    fn cmd_got(target: &mut Target, args: &[&str]) -> anyhow::Result<()> {
        let show_dyn = args.first().copied() == Some("--all") || args.first().copied() == Some("-a");

        let entries = target.got_plt_entries()?;
        if entries.is_empty() {
            println!("  {}", "no GOT/PLT entries found (statically linked?)".yellow());
        } else {
            println!("  {}", "GOT/PLT entries:".bold());
            println!(
                "  {:>18}  {:>18}  {:>18}  {}",
                "GOT addr".bold(),
                "PLT addr".bold(),
                "resolved".bold(),
                "symbol".bold()
            );
            for entry in &entries {
                let resolved = match target.read_got_value(entry.got_addr) {
                    Ok(val) => format!("0x{:016x}", val),
                    Err(_) => "<unreadable>".to_string(),
                };
                let plt_str = match entry.plt_addr {
                    Some(addr) => format!("0x{:016x}", addr),
                    None => "-".to_string(),
                };
                println!(
                    "  0x{:016x}  {:>18}  {}  {}",
                    entry.got_addr,
                    plt_str,
                    resolved.cyan(),
                    entry.name.bold()
                );
            }
        }

        if show_dyn {
            let dyn_entries = target.got_dyn_entries()?;
            if !dyn_entries.is_empty() {
                println!();
                println!("  {}", "Dynamic GOT entries (.rela.dyn):".bold());
                for entry in &dyn_entries {
                    let resolved = match target.read_got_value(entry.got_addr) {
                        Ok(val) => format!("0x{:016x}", val),
                        Err(_) => "<unreadable>".to_string(),
                    };
                    println!(
                        "  0x{:016x}  {}  {}",
                        entry.got_addr,
                        resolved.cyan(),
                        entry.name.bold()
                    );
                }
            }
        }

        Ok(())
    }

    fn cmd_strings(target: &mut Target, args: &[&str]) -> anyhow::Result<()> {
        let min_len: usize = args
            .first()
            .and_then(|s| s.parse().ok())
            .unwrap_or(4);
        let max_results: usize = args
            .get(1)
            .and_then(|s| s.parse().ok())
            .unwrap_or(200);

        let strings = target.extract_strings(min_len)?;
        let total = strings.len();

        if strings.is_empty() {
            println!("  {}", "no strings found".yellow());
            return Ok(());
        }

        println!(
            "  {} string(s) found (min length: {}, showing up to {}):",
            total, min_len, max_results
        );
        for s in strings.iter().take(max_results) {
            let section = if s.section.is_empty() {
                String::new()
            } else {
                format!(" [{}]", s.section.dimmed())
            };
            // Truncate very long strings for display
            let display = if s.content.len() > 120 {
                format!("{}...", &s.content[..120])
            } else {
                s.content.clone()
            };
            println!(
                "  {:016x}{}  {}",
                s.addr,
                section,
                display.cyan()
            );
        }
        if total > max_results {
            println!(
                "  ... and {} more (use 'strings <min_len> <max_count>' to show more)",
                total - max_results
            );
        }
        Ok(())
    }

    fn cmd_gadgets(target: &mut Target, args: &[&str]) -> anyhow::Result<()> {
        let max_depth: usize = args
            .iter()
            .find(|a| a.starts_with("--depth"))
            .and_then(|_| args.iter().find_map(|a| a.parse().ok()))
            .unwrap_or(5);

        let filter: Option<&str> = args.iter()
            .position(|&a| a == "--filter" || a == "-f")
            .and_then(|i| args.get(i + 1).copied());

        let max_results: usize = args
            .iter()
            .position(|&a| a == "--max" || a == "-n")
            .and_then(|i| args.get(i + 1).and_then(|s| s.parse().ok()))
            .unwrap_or(100);

        let gadgets = target.find_gadgets(max_depth)?;

        let display_gadgets: Vec<_> = if let Some(pat) = filter {
            rnicro::rop::filter_gadgets(&gadgets, pat)
                .into_iter()
                .cloned()
                .collect()
        } else {
            gadgets
        };

        let total = display_gadgets.len();
        if total == 0 {
            println!("  {}", "no gadgets found".yellow());
            return Ok(());
        }

        println!(
            "  {} gadget(s) found (depth: {}, showing up to {}):",
            total, max_depth, max_results
        );
        for g in display_gadgets.iter().take(max_results) {
            println!(
                "  {:016x}  {}",
                g.addr,
                g.instructions.cyan()
            );
        }
        if total > max_results {
            println!(
                "  ... and {} more (use --max N or --filter <pattern>)",
                total - max_results
            );
        }
        Ok(())
    }

    fn cmd_entropy(target: &mut Target) -> anyhow::Result<()> {
        let sections = target.section_entropy()?;
        if sections.is_empty() {
            println!("  {}", "no sections found".yellow());
            return Ok(());
        }

        println!(
            "  {:>20}  {:>12}  {:>8}  {}",
            "section".bold(),
            "size".bold(),
            "entropy".bold(),
            "classification".bold()
        );
        for s in &sections {
            let class = rnicro::entropy::classify_entropy(s.entropy);
            let entropy_str = format!("{:.4}", s.entropy);
            let colored_entropy = if s.entropy > 7.0 {
                entropy_str.red().to_string()
            } else if s.entropy > 5.5 {
                entropy_str.to_string()
            } else if s.entropy < 0.5 {
                entropy_str.dimmed().to_string()
            } else {
                entropy_str.cyan().to_string()
            };
            println!(
                "  {:>20}  {:>12}  {:>8}  {}",
                s.name.bold(),
                s.size,
                colored_entropy,
                class.dimmed()
            );
        }
        Ok(())
    }

    fn cmd_pattern(args: &[&str]) -> anyhow::Result<()> {
        match args.first().copied() {
            Some("create") | Some("c") => {
                if args.len() < 2 {
                    println!("usage: pattern create <length>");
                    return Ok(());
                }
                let length: usize = args[1]
                    .parse()
                    .map_err(|_| anyhow::anyhow!("invalid length: {}", args[1]))?;
                let pattern = rnicro::pattern::create(length)?;
                println!("{}", pattern);
            }
            Some("offset") | Some("o") => {
                if args.len() < 2 {
                    println!("usage: pattern offset <hex-value>");
                    println!("  e.g.: pattern offset 0x41306141");
                    return Ok(());
                }
                let val_str = args[1].strip_prefix("0x").unwrap_or(args[1]);
                let value = u32::from_str_radix(val_str, 16)
                    .map_err(|_| anyhow::anyhow!("invalid hex value: {}", args[1]))?;
                match rnicro::pattern::offset_of(value)? {
                    Some(offset) => {
                        println!(
                            "  pattern offset: {} (0x{:x})",
                            offset.to_string().bold(),
                            offset
                        );
                    }
                    None => {
                        println!("  {}", "pattern not found".yellow());
                    }
                }
            }
            None => {
                println!("usage: pattern create <length>");
                println!("       pattern offset <hex-value>");
            }
            Some(sub) => {
                println!("unknown pattern subcommand: {}", sub);
            }
        }
        Ok(())
    }

    fn cmd_patch(target: &mut Target, args: &[&str]) -> anyhow::Result<()> {
        if args.len() < 2 {
            println!("usage: patch <address> <hex_bytes>");
            println!("  Patches process memory (live). Use 'patch-file' for on-disk patching.");
            return Ok(());
        }
        let addr = VirtAddr(parse_address(args[0])?);
        let hex_str: String = args[1..].join("");
        let bytes = parse_hex_bytes(&hex_str)?;

        // Read original bytes first (for display)
        let original = target.read_memory(addr, bytes.len())?;
        target.write_memory(addr, &bytes)?;

        println!(
            "  patched {} byte(s) at {}",
            bytes.len(),
            format!("0x{:x}", addr.addr()).cyan()
        );
        print!("  original: ");
        for b in &original {
            print!("{:02x} ", b);
        }
        println!();
        print!("  patched:  ");
        for b in &bytes {
            print!("{:02x} ", b);
        }
        println!();
        Ok(())
    }

    fn cmd_patch_file(target: &mut Target, args: &[&str]) -> anyhow::Result<()> {
        if args.len() < 2 {
            println!("usage: patch-file <vaddr> <hex_bytes>");
            println!("  Patches the binary on disk at the given virtual address.");
            return Ok(());
        }
        let vaddr = parse_address(args[0])?;
        let hex_str: String = args[1..].join("");
        let bytes = parse_hex_bytes(&hex_str)?;

        let result = target.patch_file(vaddr, &bytes)?;
        println!(
            "  patched {} byte(s) at vaddr {} (file offset 0x{:x})",
            bytes.len(),
            format!("0x{:x}", result.vaddr).cyan(),
            result.file_offset
        );
        print!("  original: ");
        for b in &result.original_bytes {
            print!("{:02x} ", b);
        }
        println!();
        Ok(())
    }

    fn cmd_antidebug(target: &mut Target, args: &[&str]) -> anyhow::Result<()> {
        match args.first().copied() {
            Some("scan") | Some("s") | None => {
                let findings = target.antidebug_scan()?;
                if findings.is_empty() {
                    println!("  {}", "no anti-debug techniques detected".green());
                } else {
                    println!(
                        "  {} anti-debug technique(s) detected:",
                        findings.len().to_string().yellow()
                    );
                    for f in &findings {
                        let addr_str = if f.addr != 0 {
                            format!("0x{:x}", f.addr)
                        } else {
                            "-".to_string()
                        };
                        println!(
                            "  {:>16}  {:>20}  {}",
                            addr_str.cyan(),
                            format!("{}", f.technique).yellow(),
                            f.description
                        );
                    }
                }
            }
            Some("bypass") => {
                match args.get(1).copied() {
                    Some("enable") | Some("on") => {
                        let mut cfg = target.bypass_config().clone();
                        cfg.bypass_ptrace = true;
                        cfg.skip_int3_traps = true;
                        target.set_bypass_config(cfg);
                        println!("  anti-debug bypass: {}", "enabled".green());
                    }
                    Some("disable") | Some("off") => {
                        target.set_bypass_config(rnicro::antidebug::BypassConfig::default());
                        println!("  anti-debug bypass: {}", "disabled".yellow());
                    }
                    Some("status") | None => {
                        let cfg = target.bypass_config();
                        println!("  bypass_ptrace:    {}", if cfg.bypass_ptrace { "on".green().to_string() } else { "off".to_string() });
                        println!("  skip_int3_traps:  {}", if cfg.skip_int3_traps { "on".green().to_string() } else { "off".to_string() });
                    }
                    Some(sub) => println!("unknown bypass subcommand: {} (use enable|disable|status)", sub),
                }
            }
            Some(sub) => println!("unknown antidebug subcommand: {} (use scan|bypass)", sub),
        }
        Ok(())
    }

    fn cmd_heap(target: &mut Target, args: &[&str]) -> anyhow::Result<()> {
        let max_chunks: usize = args
            .iter()
            .position(|&a| a == "--max" || a == "-n")
            .and_then(|i| args.get(i + 1).and_then(|s| s.parse().ok()))
            .unwrap_or(100);

        match args.first().copied() {
            Some("chunks") | Some("c") | None => {
                let chunks = target.heap_chunks(max_chunks)?;
                if chunks.is_empty() {
                    println!("  {}", "no heap chunks found".yellow());
                    return Ok(());
                }
                println!(
                    "  {:>18}  {:>10}  {:>10}  {}",
                    "address".bold(),
                    "size".bold(),
                    "raw size".bold(),
                    "flags".bold()
                );
                for chunk in &chunks {
                    let mut flags = Vec::new();
                    if chunk.prev_inuse { flags.push("P"); }
                    if chunk.is_mmapped { flags.push("M"); }
                    if chunk.non_main_arena { flags.push("N"); }
                    let flag_str = if flags.is_empty() {
                        "-".to_string()
                    } else {
                        flags.join("|")
                    };
                    println!(
                        "  0x{:016x}  {:>10}  0x{:08x}  {}",
                        chunk.addr,
                        chunk.size,
                        chunk.size_raw,
                        flag_str.cyan()
                    );
                }
                println!("  {} chunk(s) total", chunks.len());
            }
            Some(sub) => println!("unknown heap subcommand: {} (use chunks)", sub),
        }
        Ok(())
    }

    fn cmd_coredump(target: &mut Target, args: &[&str]) -> anyhow::Result<()> {
        let filename = args.first().copied().unwrap_or("core.dump");
        println!("  generating core dump...");
        let data = target.generate_coredump()?;
        std::fs::write(filename, &data)
            .map_err(|e| anyhow::anyhow!("write core dump: {}", e))?;
        println!(
            "  core dump written to {} ({} bytes)",
            filename.bold(),
            data.len()
        );
        Ok(())
    }

    fn cmd_strace(target: &mut Target, args: &[&str]) -> anyhow::Result<()> {
        match args.first().copied() {
            Some("on") | Some("enable") | None => {
                target.set_catch_all_syscalls(true);
                println!("  syscall tracing: {} (use 'continue' to run)", "enabled".green());
                println!("  tip: use 'strace off' to disable, 'catchpoint syscall list' to see status");
            }
            Some("off") | Some("disable") => {
                target.set_catch_all_syscalls(false);
                println!("  syscall tracing: {}", "disabled".yellow());
            }
            Some(sub) => println!("unknown strace subcommand: {} (use on|off)", sub),
        }
        Ok(())
    }

    fn cmd_scan(target: &mut Target, args: &[&str]) -> anyhow::Result<()> {
        if args.is_empty() {
            println!("usage: scan pattern <hex_pattern>   (e.g. scan pattern 48 8B ?? 05)");
            println!("       scan bytes <hex_string>      (e.g. scan bytes 48656c6c6f)");
            println!("       scan string <text>           (e.g. scan string /bin/sh)");
            return Ok(());
        }
        match args[0] {
            "pattern" | "p" => {
                if args.len() < 2 {
                    println!("usage: scan pattern <hex_pattern>");
                    return Ok(());
                }
                let pattern = args[1..].join(" ");
                let matches = target.scan_hex_pattern(&pattern)?;
                print_scan_results(&matches);
            }
            "bytes" | "b" => {
                if args.len() < 2 {
                    println!("usage: scan bytes <hex_string>");
                    return Ok(());
                }
                let bytes = parse_hex_bytes(args[1])?;
                let matches = target.scan_bytes(&bytes)?;
                print_scan_results(&matches);
            }
            "string" | "s" => {
                if args.len() < 2 {
                    println!("usage: scan string <text>");
                    return Ok(());
                }
                let text = args[1..].join(" ");
                let matches = target.scan_bytes(text.as_bytes())?;
                print_scan_results(&matches);
            }
            sub => println!("unknown scan subcommand: {} (use pattern|bytes|string)", sub),
        }
        Ok(())
    }

    fn print_scan_results(matches: &[rnicro::memscan::ScanMatch]) {
        if matches.is_empty() {
            println!("  {}", "no matches found".yellow());
            return;
        }
        let max_show = 100;
        println!("  {} match(es) found:", matches.len().to_string().bold());
        for m in matches.iter().take(max_show) {
            let hex: String = m.matched_bytes.iter().map(|b| format!("{:02x}", b)).collect();
            println!("  0x{:016x}  {}", m.address, hex.cyan());
        }
        if matches.len() > max_show {
            println!("  ... and {} more", matches.len() - max_show);
        }
    }

    fn cmd_hook(target: &mut Target, args: &[&str]) -> anyhow::Result<()> {
        match args.first().copied() {
            Some("install") | Some("set") => {
                if args.len() < 3 {
                    println!("usage: hook install <function> <target_addr>");
                    return Ok(());
                }
                let func = args[1];
                let target_addr = parse_address(args[2])?;
                let idx = target.install_got_hook(func, target_addr)?;
                println!(
                    "  hook #{} installed: {} -> {}",
                    idx,
                    func.bold(),
                    format!("0x{:x}", target_addr).cyan()
                );
            }
            Some("remove") | Some("rm") => {
                if args.len() < 2 {
                    println!("usage: hook remove <function>");
                    return Ok(());
                }
                target.remove_got_hook(args[1])?;
                println!("  hook for {} removed", args[1].bold());
            }
            Some("list") | Some("l") | None => {
                let hooks = target.list_got_hooks();
                if hooks.is_empty() {
                    println!("  {}", "no active GOT hooks".yellow());
                } else {
                    println!(
                        "  {:>18}  {:>18}  {:>18}  {}",
                        "GOT addr".bold(),
                        "original".bold(),
                        "hooked to".bold(),
                        "function".bold()
                    );
                    for h in &hooks {
                        println!(
                            "  0x{:016x}  0x{:016x}  0x{:016x}  {}",
                            h.got_address.addr(),
                            h.original_target,
                            h.hook_target,
                            h.function_name.bold()
                        );
                    }
                }
            }
            Some(sub) => println!("unknown hook subcommand: {} (use install|remove|list)", sub),
        }
        Ok(())
    }

    fn cmd_fmtstr(args: &[&str]) -> anyhow::Result<()> {
        match args.first().copied() {
            Some("offset") | Some("o") => {
                let num = args.get(1).and_then(|s| s.parse::<usize>().ok()).unwrap_or(20);
                let payload = rnicro::fmtstr::generate_offset_finder("AAAAAAAA", num);
                println!("  {}", "Offset finder payload:".bold());
                println!("  {}", payload);
                println!("  tip: send this as input, then use 'fmtstr parse <output>' to find offset");
            }
            Some("parse") => {
                if args.len() < 2 {
                    println!("usage: fmtstr parse <printf_output>");
                    return Ok(());
                }
                let output = args[1..].join(" ");
                match rnicro::fmtstr::find_offset(b"AAAAAAAA", &output) {
                    Some(off) => println!("  stack offset: {}", off.to_string().bold()),
                    None => println!("  {}", "offset not found in output".yellow()),
                }
            }
            Some("write") => {
                if args.len() < 4 {
                    println!("usage: fmtstr write <offset> <address> <value> [num_bytes]");
                    return Ok(());
                }
                let offset: usize = args[1].parse().map_err(|_| anyhow::anyhow!("bad offset"))?;
                let address = parse_address(args[2])?;
                let value = parse_address(args[3])?;
                let num_bytes: usize = args.get(4).and_then(|s| s.parse().ok()).unwrap_or(8);

                let config = rnicro::fmtstr::FmtStrConfig::x86_64(offset);
                let writes = vec![rnicro::fmtstr::FmtWrite { address, value, num_bytes }];
                let payload = rnicro::fmtstr::write_payload(&config, &writes)?;

                println!("  payload ({} bytes):", payload.len());
                print!("  ");
                for b in &payload {
                    if b.is_ascii_graphic() || *b == b' ' {
                        print!("{}", *b as char);
                    } else {
                        print!("\\x{:02x}", b);
                    }
                }
                println!();
                println!("  hex: {}", payload.iter().map(|b| format!("{:02x}", b)).collect::<String>().cyan());
            }
            Some("leak") => {
                if args.len() < 2 {
                    println!("usage: fmtstr leak <offset1> [offset2] ...");
                    return Ok(());
                }
                let offsets: Vec<usize> = args[1..]
                    .iter()
                    .filter_map(|s| s.parse().ok())
                    .collect();
                let payload = rnicro::fmtstr::leak_payload(&offsets);
                println!("  {}", payload);
            }
            None => {
                println!("usage: fmtstr offset [n]           generate offset finder");
                println!("       fmtstr parse <output>       find offset from output");
                println!("       fmtstr write <off> <a> <v>  generate %hhn write payload");
                println!("       fmtstr leak <off1> [off2]   generate leak payload");
            }
            Some(sub) => println!("unknown fmtstr subcommand: {}", sub),
        }
        Ok(())
    }

    fn cmd_shellcode(args: &[&str]) -> anyhow::Result<()> {
        match args.first().copied() {
            Some("analyze") | Some("a") => {
                if args.len() < 2 {
                    println!("usage: shellcode analyze <hex_bytes>");
                    return Ok(());
                }
                let bytes = parse_hex_bytes(args[1])?;
                let result = rnicro::shellcode::analyze(&bytes, rnicro::shellcode::BAD_CHARS_BASIC);

                println!("  size: {} bytes", result.size);
                println!("  null bytes: {}", if result.has_null_bytes {
                    format!("yes ({} found)", result.null_positions.len()).red().to_string()
                } else {
                    "none".green().to_string()
                });
                println!("  bad chars (null/CR/LF): {}", result.bad_chars.len());
                println!("  syscall sites: {}", result.syscall_sites.len());
                println!("  int 0x80 sites: {}", result.int80_sites.len());
                for sled in &result.nop_sleds {
                    println!("  NOP sled: offset {} ({} bytes)", sled.offset, sled.length);
                }
            }
            Some("encode") | Some("e") => {
                if args.len() < 3 {
                    println!("usage: shellcode encode <hex_bytes> <xor_key_hex>");
                    return Ok(());
                }
                let bytes = parse_hex_bytes(args[1])?;
                let key = u8::from_str_radix(args[2].strip_prefix("0x").unwrap_or(args[2]), 16)
                    .map_err(|_| anyhow::anyhow!("invalid key: {}", args[2]))?;
                let encoded = rnicro::shellcode::xor_encode(&bytes, key);
                println!("  encoded: {}", encoded.iter().map(|b| format!("{:02x}", b)).collect::<String>().cyan());
            }
            Some("findkey") | Some("fk") => {
                if args.len() < 2 {
                    println!("usage: shellcode findkey <hex_bytes>");
                    return Ok(());
                }
                let bytes = parse_hex_bytes(args[1])?;
                match rnicro::shellcode::find_xor_key(&bytes, rnicro::shellcode::BAD_CHARS_BASIC) {
                    Some(key) => println!("  XOR key: {} (avoids null/CR/LF)", format!("0x{:02x}", key).bold()),
                    None => println!("  {}", "no suitable key found".yellow()),
                }
            }
            None => {
                println!("usage: shellcode analyze <hex>    analyze shellcode properties");
                println!("       shellcode encode <hex> <k> XOR encode with key");
                println!("       shellcode findkey <hex>    find XOR key avoiding bad chars");
            }
            Some(sub) => println!("unknown shellcode subcommand: {}", sub),
        }
        Ok(())
    }

    fn cmd_sigrop(args: &[&str]) -> anyhow::Result<()> {
        match args.first().copied() {
            Some("execve") => {
                if args.len() < 3 {
                    println!("usage: sigrop execve <syscall_addr> <binsh_addr>");
                    return Ok(());
                }
                let syscall_addr = parse_address(args[1])?;
                let binsh_addr = parse_address(args[2])?;
                let frame = rnicro::sigrop::execve_frame(syscall_addr, binsh_addr);
                let bytes = frame.to_bytes();
                println!("  execve(\"/bin/sh\") sigframe ({} bytes):", bytes.len());
                println!("  rax={} rdi={} rip={}",
                    "59".bold(), format!("0x{:x}", binsh_addr).cyan(), format!("0x{:x}", syscall_addr).cyan());
                println!("  hex: {}", bytes.iter().map(|b| format!("{:02x}", b)).collect::<String>());
            }
            Some("mprotect") => {
                if args.len() < 5 {
                    println!("usage: sigrop mprotect <syscall_addr> <addr> <len> <prot>");
                    return Ok(());
                }
                let syscall_addr = parse_address(args[1])?;
                let addr = parse_address(args[2])?;
                let len = parse_address(args[3])?;
                let prot = parse_address(args[4])?;
                let frame = rnicro::sigrop::mprotect_frame(syscall_addr, addr, len, prot);
                let bytes = frame.to_bytes();
                println!("  mprotect sigframe ({} bytes):", bytes.len());
                println!("  hex: {}", bytes.iter().map(|b| format!("{:02x}", b)).collect::<String>());
            }
            Some("chain") => {
                if args.len() < 4 {
                    println!("usage: sigrop chain <sigret_addr> <syscall_addr> <binsh_addr>");
                    return Ok(());
                }
                let sigret_addr = parse_address(args[1])?;
                let syscall_addr = parse_address(args[2])?;
                let binsh_addr = parse_address(args[3])?;
                let chain = rnicro::sigrop::build_chain(
                    sigret_addr,
                    &[rnicro::sigrop::execve_frame(syscall_addr, binsh_addr)],
                );
                println!("  SROP chain ({} bytes):", chain.len());
                println!("  hex: {}", chain.iter().map(|b| format!("{:02x}", b)).collect::<String>());
            }
            None => {
                println!("usage: sigrop execve <sys> <binsh>         execve frame");
                println!("       sigrop mprotect <sys> <a> <l> <p>   mprotect frame");
                println!("       sigrop chain <sigret> <sys> <binsh> full SROP chain");
            }
            Some(sub) => println!("unknown sigrop subcommand: {}", sub),
        }
        Ok(())
    }

    fn cmd_help() -> anyhow::Result<()> {
        println!("{}", "rnicro - Linux x86_64 debugger & exploit development toolkit".bold());
        println!();
        println!("  {} (c)          resume execution", "continue".bold());
        println!(
            "  {} (si)            single-step one instruction",
            "stepi".bold()
        );
        println!(
            "  {} (s)              source-level step into",
            "step".bold()
        );
        println!(
            "  {} (n)              source-level step over",
            "next".bold()
        );
        println!(
            "  {} (fin)          step out of current function",
            "finish".bold()
        );
        println!(
            "  {} (r)          read/write registers",
            "register".bold()
        );
        println!("    register read          show all registers");
        println!("    register write <n> <v> set register");
        println!(
            "  {} (b)       manage breakpoints",
            "breakpoint".bold()
        );
        println!("    breakpoint set <addr>   set a breakpoint");
        println!("    breakpoint set <a> if E conditional breakpoint");
        println!("    breakpoint delete <a>   remove a breakpoint");
        println!("    breakpoint list         list all breakpoints");
        println!(
            "  {} (x)            read/write memory / maps",
            "memory".bold()
        );
        println!("    memory read <addr> [n]  hex dump");
        println!("    memory write <addr> <h> write hex bytes (e.g. 90909090)");
        println!("    memory maps             show memory mappings");
        println!(
            "  {} (d)     disassemble instructions",
            "disassemble".bold()
        );
        println!("    disassemble [addr] [N] disassemble N instructions");
        println!("    disassemble --att     use AT&T syntax");
        println!(
            "  {} (bt)         show call stack",
            "backtrace".bold()
        );
        println!(
            "  {} (wp)       hardware watchpoints",
            "watchpoint".bold()
        );
        println!("    watchpoint set <a> <t> <s> set watchpoint (type: write|rw|execute, size: 1|2|4|8)");
        println!("    watchpoint delete <id>     remove watchpoint");
        println!("    watchpoint list            list watchpoints");
        println!(
            "  {} (catch)    manage syscall catchpoints",
            "catchpoint".bold()
        );
        println!("    catch syscall add <name>   catch a syscall");
        println!("    catch syscall add all      catch all syscalls");
        println!("    catch syscall remove <n>   remove catchpoint");
        println!("    catch syscall list         show catchpoints");
        println!(
            "  {} (sig)          configure signal handling",
            "signal".bold()
        );
        println!("    signal handle <sig> <act>  set policy (stop|nostop|pass|nopass)");
        println!("    signal list                show all signal policies");
        println!(
            "  {} (p)             print a variable's value",
            "print".bold()
        );
        println!(
            "  {}             list local variables",
            "locals".bold()
        );
        println!(
            "  {} (thr)          list all threads",
            "threads".bold()
        );
        println!(
            "  {} (t)            switch to thread by tid",
            "thread".bold()
        );
        println!(
            "  {} (libs)           list loaded shared libraries",
            "sharedlib".bold()
        );
        println!(
            "  {}            analyze binary security features",
            "checksec".bold()
        );
        println!(
            "  {} / {}             show GOT/PLT entries (--all for .rela.dyn)",
            "got".bold(),
            "plt".bold()
        );
        println!(
            "  {} (str)         extract strings [min_len] [max_count]",
            "strings".bold()
        );
        println!(
            "  {} (rop)        search ROP gadgets [--depth N] [--filter S]",
            "gadgets".bold()
        );
        println!(
            "  {}            per-section Shannon entropy analysis",
            "entropy".bold()
        );
        println!(
            "  {} (pat)          cyclic pattern create|offset",
            "pattern".bold()
        );
        println!(
            "  {}              live memory patch: patch <addr> <hex>",
            "patch".bold()
        );
        println!(
            "  {}         on-disk patch: patch-file <vaddr> <hex>",
            "patch-file".bold()
        );
        println!(
            "  {}         scan for anti-debug techniques",
            "antidebug".bold()
        );
        println!("    antidebug scan             detect anti-debug patterns");
        println!("    antidebug bypass enable     enable bypass hooks");
        println!("    antidebug bypass disable    disable bypass hooks");
        println!(
            "  {}               inspect glibc heap chunks",
            "heap".bold()
        );
        println!("    heap chunks [--max N]       walk malloc_chunk chain");
        println!(
            "  {}           generate ELF core dump",
            "coredump".bold()
        );
        println!("    coredump [filename]         dump to file (default: core.dump)");
        println!(
            "  {}             enhanced syscall tracing",
            "strace".bold()
        );
        println!("    strace on                   enable strace-like output");
        println!("    strace off                  disable tracing");
        println!(
            "  {}              scan process memory for patterns",
            "scan".bold()
        );
        println!("    scan pattern <hex>          IDA-style hex pattern (e.g. 48 8B ?? 05)");
        println!("    scan bytes <hex>            exact byte search");
        println!("    scan string <text>          string search in memory");
        println!(
            "  {}               GOT/PLT function hooking",
            "hook".bold()
        );
        println!("    hook install <func> <addr>  redirect function via GOT");
        println!("    hook remove <func>          restore original GOT entry");
        println!("    hook list                   show active hooks");
        println!(
            "  {} (fmt)          format string exploit helper",
            "fmtstr".bold()
        );
        println!("    fmtstr offset [n]           offset finder payload");
        println!("    fmtstr write <off> <a> <v>  %hhn write payload");
        println!("    fmtstr leak <off1> ...      stack leak payload");
        println!(
            "  {} (sc)      shellcode analysis toolkit",
            "shellcode".bold()
        );
        println!("    shellcode analyze <hex>     detect null/bad/syscall/NOP");
        println!("    shellcode encode <hex> <k>  XOR encode");
        println!("    shellcode findkey <hex>     find null-free XOR key");
        println!(
            "  {} (srop)         SROP chain builder",
            "sigrop".bold()
        );
        println!("    sigrop execve <sys> <binsh> execve sigreturn frame");
        println!("    sigrop mprotect <s> <a> ... mprotect sigreturn frame");
        println!("    sigrop chain <sr> <s> <b>   full SROP chain");
        println!(
            "  {} (l)              show source at current PC",
            "list".bold()
        );
        println!("  {} (h)              this help", "help".bold());
        println!("  {} (q)              exit", "quit".bold());
        println!();
        println!(
            "{}",
            "Library-only APIs (available via rnicro crate):".bold()
        );
        println!("  aslr           ASLR/PIE leak calculator, libc offset database");
        println!("  rop_chain      automated ROP chain builder (execve, mprotect)");
        println!("  one_gadget     one-gadget / magic gadget finder for libc");
        println!("  heap_exploit   tcache poison, fastbin dup, House of Force");
        println!("  tube           pwntools-style process I/O tubes");
        Ok(())
    }

    /// Print a stop reason.
    fn print_stop_reason(reason: &StopReason) {
        match reason {
            StopReason::BreakpointHit { addr } => {
                println!("  {} at {}", "breakpoint hit".yellow(), addr);
            }
            StopReason::SingleStep => {
                println!("  {}", "single step".dimmed());
            }
            StopReason::Signal(sig) => {
                println!("  received signal: {:?}", sig);
            }
            StopReason::SyscallEntry { number, args } => {
                // Use enhanced formatting from syscall_trace
                let no_read = |_addr: u64| -> rnicro::error::Result<String> {
                    Err(rnicro::error::Error::Other("no read".into()))
                };
                let formatted = rnicro::syscall_trace::format_syscall_entry(
                    *number, args, &no_read,
                );
                println!(
                    "  {} {}",
                    "syscall:".yellow(),
                    formatted,
                );
            }
            StopReason::SyscallExit { number, retval } => {
                let name = rnicro::syscall::name(*number)
                    .unwrap_or("unknown");
                let ret_str = rnicro::syscall_trace::format_syscall_return(*number, *retval);
                let colored_ret = if *retval < 0 {
                    ret_str.red().to_string()
                } else {
                    ret_str
                };
                println!(
                    "  {} {}() = {}",
                    "syscall exit:".yellow(),
                    name.bold(),
                    colored_ret,
                );
            }
            StopReason::WatchpointHit { slot, addr } => {
                println!(
                    "  {} at {} (slot {})",
                    "watchpoint hit".yellow(),
                    addr,
                    slot,
                );
            }
            StopReason::Exited(code) => {
                println!("  process exited with code {}", code);
            }
            StopReason::Terminated(sig) => {
                println!("  process terminated by signal {:?}", sig);
            }
            StopReason::ThreadCreated(pid) => {
                println!("  new thread created: {}", pid);
            }
            StopReason::ThreadExited(tid) => {
                println!("  thread {} exited", tid);
            }
        }
    }

    /// Print thread info when there are multiple threads.
    fn print_thread_info(target: &Target) {
        let threads = target.thread_list();
        if threads.len() > 1 {
            println!(
                "  [thread {} of {}]",
                target.current_tid(),
                threads.len()
            );
        }
    }

    /// Print source location and function name (if available).
    fn print_location(target: &Target) {
        if let Ok(Some(loc)) = target.source_location() {
            print!("  at {}", loc.to_string().bold());
            if let Ok(Some(func)) = target.current_function() {
                print!(" in {}", func.cyan());
            }
            println!();
        }
    }

    fn print_hexdump(base: VirtAddr, data: &[u8]) {
        for (i, chunk) in data.chunks(16).enumerate() {
            let addr = base.addr() + (i * 16) as u64;
            print!("  {:016x}  ", addr);
            for (j, byte) in chunk.iter().enumerate() {
                if j == 8 {
                    print!(" ");
                }
                print!("{:02x} ", byte);
            }
            for j in chunk.len()..16 {
                if j == 8 {
                    print!(" ");
                }
                print!("   ");
            }
            print!(" |");
            for byte in chunk {
                if byte.is_ascii_graphic() || *byte == b' ' {
                    print!("{}", *byte as char);
                } else {
                    print!(".");
                }
            }
            println!("|");
        }
    }

    /// Resolve an address argument that may be a hex address or a symbol name.
    fn resolve_address(target: &Target, s: &str) -> anyhow::Result<VirtAddr> {
        // Try parsing as hex address first
        if let Ok(addr) = parse_address(s) {
            return Ok(VirtAddr(addr));
        }
        // Try symbol lookup
        if let Some(addr) = target.find_symbol(s) {
            return Ok(addr);
        }
        Err(anyhow::anyhow!(
            "'{}' is not a valid address or known symbol",
            s
        ))
    }

    fn parse_address(s: &str) -> anyhow::Result<u64> {
        let s = s.strip_prefix("0x").unwrap_or(s);
        u64::from_str_radix(s, 16)
            .map_err(|e| anyhow::anyhow!("invalid address '{}': {}", s, e))
    }

    /// Parse a hex string like "90909090" or "cc90" into bytes.
    fn parse_hex_bytes(s: &str) -> anyhow::Result<Vec<u8>> {
        let s = s.strip_prefix("0x").unwrap_or(s);
        // Remove any whitespace or \x separators
        let clean: String = s
            .replace("\\x", "")
            .replace(' ', "")
            .replace(':', "");

        if clean.len() % 2 != 0 {
            return Err(anyhow::anyhow!(
                "hex string must have even number of digits, got {}",
                clean.len()
            ));
        }

        let mut bytes = Vec::with_capacity(clean.len() / 2);
        for chunk in clean.as_bytes().chunks(2) {
            let hex = std::str::from_utf8(chunk).unwrap();
            let byte = u8::from_str_radix(hex, 16)
                .map_err(|_| anyhow::anyhow!("invalid hex byte: '{}'", hex))?;
            bytes.push(byte);
        }
        Ok(bytes)
    }
}