使用Shell脚本从另一个文件检查用户名和密码

Question

I'm new to shell, I want to do the following task

A shell program which accepts username and password and checks the $username and $password with a line in another file (for authentication), I know how to get the username from user but how do I check against a line in another file. say I have a file called username (which has the username) and file called password (which has the password) how do I check $username with that line and $password with that line in the file

Answer 1

Straight from the perl cookbook: (I guess it's no good though because the OP wanted bash)

#!/usr/bin/perl -w
# 

checkuser - demonstrates reading and checking a user's password

use Term::ReadKey;

print "Enter your password: ";
ReadMode 'noecho';
$password = ReadLine 0;
chomp $password;
ReadMode 'normal';

print "\n";

($username, $encrypted) = ( getpwuid $< )[0,1];

if (crypt($password, $encrypted) ne $encrypted) {
    die "You are not $username\n";
} else {
    print "Welcome, $username\n";
}

Answer 2

Super basic and has no security but this should work for finding them in a file

How i think it should be done(single file)

echo 'Type username'
read username
echo 'Type Password'
read -s Password
awk /^$username.*$Password$/' {print "found"}' loginfile

For the way OP has files set up

echo 'Type username'
read username
echo 'Type Password'
read -s Password
UserCheck=$(awk /^$username$/' {print "1"}' Username.txt)
PassCheck=$(awk /^$Password$/' {print "1"}' Password.txt)

if [[ UserCheck -eq 1 && PassCheck -eq 1 ]]; then
     echo "Found"
else
     echo "not found"
fi

Answer 3

Here is an example script which prompts the user to enter a username and password and then compares them against the username and password taken from two files:

#!/bin/bash

# prompt the user to enter a username and password
read -p "Username: " inputUsername
read -s -p "Password: " inputPassword

# read the username and password from file
username=$(<username.txt)
password=$(<password.txt)

# compare
if [[ "$inputUsername" == "$username" && "$inputPassword" == "$password" ]]
then
    echo "valid username and password"
else
    echo "invalid username and password"
fi