WIP passwd implementation

src/bin/passwd.rs

@@ -1,11 +1,109 @@
 extern crate rand;
+extern crate syscall;
+extern crate termion;
 extern crate userutils;
 
 use rand::{Rng, OsRng};
-use std::env;
+use std::{env, io};
+use std::fs::File;
+use std::io::{Read, Write};
+use termion::input::TermRead;
+use userutils::Passwd;
 
 fn main() {
-    let passwd = env::args().nth(1).unwrap();
-    let salt = format!("{:X}", OsRng::new().unwrap().next_u64());
-    println!("{}", userutils::Passwd::encode(&passwd, &salt));
+    let stdin = io::stdin();
+    let mut stdin = stdin.lock();
+    let stdout = io::stdout();
+    let mut stdout = stdout.lock();
+
+    let uid = syscall::getuid().unwrap() as u32;
+
+    let mut passwd_string = String::new();
+    File::open("/etc/passwd").unwrap().read_to_string(&mut passwd_string).unwrap();
+
+    let passwd = if let Some(user) = env::args().nth(1) {
+        let mut passwd_option = None;
+        for line in passwd_string.lines() {
+            if let Ok(passwd) = Passwd::parse(line) {
+                if passwd.user == user {
+                    passwd_option = Some(passwd);
+                    break;
+                }
+            }
+        }
+        if let Some(passwd) = passwd_option {
+            passwd
+        } else {
+            panic!("passwd: user '{}' does not exist", user);
+        }
+    } else {
+        let mut passwd_option = None;
+        for line in passwd_string.lines() {
+            if let Ok(passwd) = Passwd::parse(line) {
+                if passwd.uid == uid {
+                    passwd_option = Some(passwd);
+                    break;
+                }
+            }
+        }
+        if let Some(passwd) = passwd_option {
+            passwd
+        } else {
+            panic!("passwd: current user id {} does not exist", uid);
+        }
+    };
+
+    if passwd.uid == uid || uid == 0 {
+        writeln!(stdout, "changing password for '{}'", passwd.user).unwrap();
+        let _ = stdout.flush();
+
+        let mut verified = false;
+        if passwd.hash == "" {
+            verified = true;
+        } else if passwd.uid == uid || uid != 0 {
+            stdout.write_all(b"current password: ").unwrap();
+            let _ = stdout.flush();
+
+            if let Some(password) = stdin.read_passwd(&mut stdout).unwrap() {
+                stdout.write(b"\n").unwrap();
+                let _ = stdout.flush();
+
+                if passwd.verify(&password) {
+                    verified = true;
+                }
+            }
+        } else {
+            verified = true;
+        }
+
+        if verified {
+            stdout.write_all(b"new password: ").unwrap();
+            let _ = stdout.flush();
+
+            if let Some(new_password) = stdin.read_passwd(&mut stdout).unwrap() {
+                stdout.write(b"\nconfirm password: ").unwrap();
+                let _ = stdout.flush();
+
+                if let Some(confirm_password) = stdin.read_passwd(&mut stdout).unwrap() {
+                    stdout.write(b"\n").unwrap();
+                    let _ = stdout.flush();
+                    
+                    if new_password == confirm_password {
+                        let salt = format!("{:X}", OsRng::new().unwrap().next_u64());
+                        writeln!(stdout, "{}", userutils::Passwd::encode(&new_password, &salt)).unwrap();
+                    } else {
+                        panic!("passwd: new password does not match confirm password");
+                    }
+                } else {
+                    panic!("passwd: no confirm password provided");
+                }
+            } else {
+                panic!("passwd: no new password provided");
+            }
+        } else {
+            panic!("passwd: incorrect current password");
+        }
+    } else {
+        panic!("passwd: you do not have permission to set the password of '{}'", passwd.user);
+    }
 }