commit 91b05ddcf0b32f135390b2c0d1dbd89ad87ec3e5
Author: Sijmen Schoon <me@sijmenschoon.nl>
Date:   Sun Jul 29 17:48:16 2018 +0200

    Initial commit

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..53eaa21
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,2 @@
+/target
+**/*.rs.bk
diff --git a/Cargo.lock b/Cargo.lock
new file mode 100644
index 0000000..1042c71
--- /dev/null
+++ b/Cargo.lock
@@ -0,0 +1,68 @@
+[[package]]
+name = "byteorder"
+version = "1.2.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "glob"
+version = "0.2.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "hex"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "kernel32-sys"
+version = "0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "winapi 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi-build 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "libc"
+version = "0.2.42"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "netstat-rust"
+version = "0.1.0"
+dependencies = [
+ "byteorder 1.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "glob 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)",
+ "hex 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "terminal_size 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "terminal_size"
+version = "0.1.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "kernel32-sys 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.42 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "winapi"
+version = "0.2.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "winapi-build"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[metadata]
+"checksum byteorder 1.2.3 (registry+https://github.com/rust-lang/crates.io-index)" = "74c0b906e9446b0a2e4f760cdb3fa4b2c48cdc6db8766a845c54b6ff063fd2e9"
+"checksum glob 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)" = "8be18de09a56b60ed0edf84bc9df007e30040691af7acd1c41874faac5895bfb"
+"checksum hex 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)" = "805026a5d0141ffc30abb3be3173848ad46a1b1664fe632428479619a3644d77"
+"checksum kernel32-sys 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "7507624b29483431c0ba2d82aece8ca6cdba9382bff4ddd0f7490560c056098d"
+"checksum libc 0.2.42 (registry+https://github.com/rust-lang/crates.io-index)" = "b685088df2b950fccadf07a7187c8ef846a959c142338a48f9dc0b94517eb5f1"
+"checksum terminal_size 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)" = "ef4f7fdb2a063032d361d9a72539380900bc3e0cd9ffc9ca8b677f8c855bae0f"
+"checksum winapi 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)" = "167dc9d6949a9b857f3451275e911c3f44255842c1f7a76f33c55103a909087a"
+"checksum winapi-build 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "2d315eee3b34aca4797b2da6b13ed88266e6d612562a0c46390af8299fc699bc"
diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..631feb2
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,10 @@
+[package]
+name = "netstat-rust"
+version = "0.1.0"
+authors = ["Sijmen Schoon <me@sijmenschoon.nl>"]
+
+[dependencies]
+glob = "0.2.11"
+hex = "0.3.2"
+byteorder = "1.2.3"
+terminal_size = "0.1.7"
diff --git a/src/main.rs b/src/main.rs
new file mode 100644
index 0000000..880350a
--- /dev/null
+++ b/src/main.rs
@@ -0,0 +1,199 @@
+extern crate glob;
+extern crate hex;
+extern crate byteorder;
+extern crate terminal_size;
+
+use std::fs::{File, read_link};
+use std::io::{BufRead, BufReader};
+use std::collections::HashMap;
+use std::net::{IpAddr, Ipv4Addr, Ipv6Addr};
+use std::fmt;
+
+use byteorder::{ByteOrder, LittleEndian};
+use glob::glob;
+use terminal_size::{Width, terminal_size};
+
+
+fn parse_ipv4(ip: &str) -> IpAddr {
+    let bytes = hex::decode(ip).unwrap();
+    let ipv4 = Ipv4Addr::new(bytes[3], bytes[2], bytes[1], bytes[0]);
+    IpAddr::V4(ipv4)
+}
+
+
+fn parse_ipv6(ip: &str) -> IpAddr {
+    let bytes = hex::decode(ip).unwrap();
+    let mut words = [0; 8];
+
+    LittleEndian::read_u16_into(&bytes, &mut words);
+
+    let ipv6 = Ipv6Addr::new(words[7], words[6], words[5], words[4],
+                             words[3], words[2], words[1], words[0]);
+    IpAddr::V6(ipv6)
+}
+
+
+enum Protocol {
+    Tcp,
+    Udp,
+}
+
+impl fmt::Display for Protocol {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "{}", match self {
+            Protocol::Tcp => "tcp",
+            Protocol::Udp => "udp",
+        })
+    }
+}
+
+struct Process {
+    pid: usize,
+    command_line: Option<String>,
+}
+
+struct Address<'a> {
+    ip: IpAddr,
+    port: u16,
+    protocol: &'a Protocol,
+}
+
+impl<'a> fmt::Display for Address<'a> {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        match self.ip.is_ipv4() {
+            true  => write!(f, "{}  {}:{}", self.protocol, self.ip, self.port),
+            false => write!(f, "{}  [{}]:{}", self.protocol, self.ip, self.port)
+        }
+    }
+}
+
+struct INode<'a> {
+    processes: Vec<Process>,
+    addresses: Vec<Address<'a>>,
+}
+
+impl<'a> INode<'a> {
+    fn new() -> INode<'a> {
+        INode {
+            processes: Vec::new(),
+            addresses: Vec::new(),
+        }
+    }
+}
+
+
+fn get_inodes(inodes: &mut HashMap<usize, INode>) {
+    for fd in glob("/proc/*/fd/*").unwrap() {
+        let path = match fd {
+            Ok(value) => value,
+            Err(_) => continue,
+        };
+        let path_str = path.to_str().unwrap();
+
+        let target = match read_link(path_str) {
+            Ok(value) => value,
+            Err(_) => continue,
+        };
+
+        let target_str = target.to_str().unwrap();
+        let pid = path_str.split("/").nth(2).unwrap().parse();
+        if !pid.is_ok() {
+            continue;
+        }
+
+        if target_str.starts_with("socket") {
+            let inode_str = target_str.splitn(2, ":").nth(1).unwrap();
+            let inode = inode_str[1..(inode_str.len() - 1)].parse().unwrap();
+
+            let mut inode = inodes.entry(inode).or_insert(INode::new());
+            let process = Process { pid: pid.unwrap(), command_line: None };
+            inode.processes.push(process);
+        }
+    }
+}
+
+
+fn get_command_lines(inodes: &mut HashMap<usize, INode>) {
+    for inode in inodes.values_mut() {
+        for process in inode.processes.iter_mut() {
+            let filename = format!("/proc/{}/cmdline", process.pid);
+            let file = File::open(filename).unwrap();
+            let mut buffer = BufReader::new(file);
+
+            let mut command_line = String::new();
+            buffer.read_line(&mut command_line).unwrap();
+
+            process.command_line = Some(command_line);
+        }
+    }
+}
+
+
+fn get_addresses(inodes: &mut HashMap<usize, INode>) {
+    for protocol in [Protocol::Tcp, Protocol::Udp].iter() {
+        for version in ["", "6"].iter() {
+            let filename = format!("/proc/net/{}{}", protocol, version);
+            let file = File::open(filename).unwrap();
+            let buffer = BufReader::new(file);
+
+            let connections = buffer.lines().skip(1).map(|line| line.unwrap());
+            for connection in connections {
+                let fields: Vec<&str> = connection.split_whitespace().collect();
+
+                let state = fields[3];
+                if state != "0A" && state != "07" {
+                    // Skip if the connection isn't listening.
+                    continue;
+                }
+
+                let address: Vec<&str> = fields[1].split(":").collect();
+                let ip = match version { &"6" => parse_ipv6, _ => parse_ipv4 }(address[0]);
+                let port = u16::from_str_radix(address[1], 16).unwrap();
+
+                let inode_id = fields[9].parse().unwrap();
+                let mut inode = match inodes.get_mut(&inode_id) {
+                    Some(value) => value,
+                    None => continue,
+                };
+                inode.addresses.push(Address { ip, port, protocol });
+            }
+        }
+    }
+}
+
+
+fn print_all(inodes: &HashMap<usize, INode>) {
+    let columns = match terminal_size() {
+        Some((Width(value), _)) => usize::from(value),
+        None => 80,
+    };
+
+    let mut values: Vec<&INode> = inodes.values().collect();
+    values.sort_unstable_by(|a, b| a.processes[0].pid.cmp(&b.processes[0].pid));
+
+    for inode in values {
+        for address in &inode.addresses {
+            for (i, process) in inode.processes.iter().enumerate() {
+                let command_line = process.command_line.clone().unwrap_or("".to_owned());
+                let address_str = if i == 0 { format!("{}", address) } else { String::new() };
+
+                let mut output = format!(
+                    "{: <45} {: >6} {}", address_str, process.pid, command_line);
+                output.truncate(columns);
+
+                println!("{}", output);
+            }
+        }
+    }
+}
+
+
+fn main() {
+    let mut inodes: HashMap<usize, INode> = HashMap::new();
+
+    get_inodes(&mut inodes);
+    get_command_lines(&mut inodes);
+    get_addresses(&mut inodes);
+
+    print_all(&inodes);
+}