From a3e1d5fdf05eb74810f29f29d57bc8e3d741797f Mon Sep 17 00:00:00 2001
From: pyro <kevin.gunter@rocketweasle.site>
Date: Tue, 27 Oct 2026 11:11:13 -0500
Subject: [PATCH] wrote the tool

---
 Cargo.toml  |   8 +++
 README.md   |   5 +-
 src/main.rs | 139 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 151 insertions(+), 1 deletion(-)
 create mode 100644 Cargo.toml
 create mode 100644 src/main.rs

diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..92a4f0f
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,8 @@
+[package]
+name = "scope_filter"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
+clap = { version = "4.6.7", features = ["derive"] }
+ipnet = "2.12.2"
diff --git a/README.md b/README.md
index 00d3051..175df75 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,6 @@
 # scope_filter
 
-Takes your scope and exclusion list, then removes the excluded IPs and outputs the remaining IPs.
\ No newline at end of file
+Takes your scope and exclusion list, then removes the excluded IPs and outputs the remaining IPs.
+
+# Usage:
+scope_filter -s /path/to/scope/file (formated one ip/range/subnet per line) -e /path/to/exclusions/file (formated one ip/range/subnet per line) -o /path/to/output/file
diff --git a/src/main.rs b/src/main.rs
new file mode 100644
index 0000000..5dc3632
--- /dev/null
+++ b/src/main.rs
@@ -0,0 +1,139 @@
+use clap::Parser;
+use ipnet::{Ipv4AddrRange, Ipv4Net};
+use std::collections::HashSet;
+use std::fs::File;
+use std::io::{self, BufRead, BufReader, Write};
+use std::net::Ipv4Addr;
+use std::path::PathBuf;
+use std::str::FromStr;
+
+#[derive(Parser, Debug)]
+#[command(
+    name = "Subnet Processor",
+    author,
+    version,
+    about = "Removes excluded IPs/subnets/ranges from input subnets, ranges, or IPs and outputs ranges or single IPs."
+)]
+struct Args {
+    #[arg(short, long, value_name = "SCOPE_FILE")]
+    scope_file: PathBuf,
+
+    #[arg(short, long, value_name = "EXCLUSION_FILE")]
+    exclusion_file: PathBuf,
+
+    #[arg(short, long, value_name = "OUTPUT_FILE")]
+    output_file: PathBuf,
+}
+
+fn main() -> io::Result<()> {
+    let args = Args::parse();
+    let subnet_lines = read_lines_to_vec(&args.scope_file)?;
+    let exclusion_lines = read_lines_to_vec(&args.exclusion_file)?;
+    let mut excluded_ips = HashSet::new();
+    for line in exclusion_lines {
+        match parse_ip_entry(&line) {
+            Ok(ips) => {
+                for ip in ips {
+                    excluded_ips.insert(ip);
+                }
+            }
+            Err(e) => {
+                eprintln!("Invalid exclusion entry '{}': {}", line, e);
+            }
+        }
+    }
+    let mut output_file = File::create(&args.output_file)?;
+    for subnet_str in subnet_lines {
+        let subnet_ips = match parse_ip_entry(&subnet_str) {
+            Ok(ips) => ips,
+            Err(e) => {
+                eprintln!("Invalid input entry '{}': {}", subnet_str, e);
+                continue;
+            }
+        };
+        if subnet_ips.is_empty() {
+            continue;
+        }
+        let remaining_ips: Vec<Ipv4Addr> = subnet_ips
+            .into_iter()
+            .filter(|ip| !excluded_ips.contains(ip))
+            .collect();
+        if remaining_ips.is_empty() {
+            continue;
+        }
+        let mut ranges: Vec<(Ipv4Addr, Ipv4Addr)> = Vec::new();
+        let mut range_start = remaining_ips[0];
+        let mut range_end = remaining_ips[0];
+        for &ip in remaining_ips.iter().skip(1) {
+            if u32::from(ip) == u32::from(range_end) + 1 {
+                range_end = ip;
+            } else {
+                ranges.push((range_start, range_end));
+                range_start = ip;
+                range_end = ip;
+            }
+        }
+        ranges.push((range_start, range_end));
+        for (start, end) in ranges {
+            if start == end {
+                writeln!(output_file, "{}", start)?;
+            } else {
+                writeln!(output_file, "{}-{}", start, end)?;
+            }
+        }
+    }
+    println!(
+        "Processing complete! Output written to '{}'.",
+        args.output_file.display()
+    );
+    Ok(())
+}
+fn parse_ip_entry(s: &str) -> io::Result<Vec<Ipv4Addr>> {
+    let s = s.trim();
+    if s.is_empty() {
+        return Ok(Vec::new());
+    }
+    if let Ok(ip) = Ipv4Addr::from_str(s) {
+        return Ok(vec![ip]);
+    }
+    if let Ok(net) = Ipv4Net::from_str(s) {
+        let range = Ipv4AddrRange::new(net.network(), net.broadcast());
+        return Ok(range.collect());
+    }
+    if let Some((start_str, end_str)) = s.split_once('-') {
+        let start = Ipv4Addr::from_str(start_str.trim())
+            .map_err(|e| io::Error::new(io::ErrorKind::InvalidInput, e.to_string()))?;
+        let end = Ipv4Addr::from_str(end_str.trim())
+            .map_err(|e| io::Error::new(io::ErrorKind::InvalidInput, e.to_string()))?;
+
+        if u32::from(start) > u32::from(end) {
+            return Err(io::Error::new(
+                io::ErrorKind::InvalidInput,
+                format!("Invalid range {}: start IP is greater than end IP", s),
+            ));
+        }
+
+        let range = Ipv4AddrRange::new(start, end);
+        return Ok(range.collect());
+    }
+    Err(io::Error::new(
+        io::ErrorKind::InvalidInput,
+        format!("Unrecognized IP format: {}", s),
+    ))
+}
+fn read_lines_to_vec<P>(filename: P) -> io::Result<Vec<String>>
+where
+    P: AsRef<std::path::Path>,
+{
+    let file = File::open(filename)?;
+    let reader = BufReader::new(file);
+    let mut lines = Vec::new();
+    for line in reader.lines() {
+        let line = line?;
+        let trimmed = line.trim();
+        if !trimmed.is_empty() {
+            lines.push(trimmed.to_string());
+        }
+    }
+    Ok(lines)
+}