The set_temporary_password.sh script is designed to set a temporary password for a specified user account on a Linux system. The password will be valid for a predefined duration, after which it will expire. Users can define parameters such as the username, expiration time in minutes, and the desired password length. The script also verifies the …

set_temporary_password.sh

#!/bin/bash

# Define parameters at the top
USERNAME="max.mustermann"        # Username for which to set the password
USER_PASSWORD=""                 # Leave empty to generate a password automatically
EXPIRATION_MINUTES=60            # Password expiration time in minutes
PASSWORD_LENGTH=6                # Length of the generated password
USE_SPECIAL=false                # Set to false to exclude special characters in the password

# Function to check if the user exists and provide output
user_exists() {
    local username="$1"
    if id "$username" &>/dev/null; then
        echo "User '$username' exists."
        return 0  # User exists
    else
        echo "User '$username' does not exist. Please check the username."
        return 1  # User does not exist
    fi
}

# Function to generate a random password
generate_password() {
    local length="${1:-6}"  # Default length is 6
    local use_special="${2:-false}"  # Default is no special characters

    if [[ "$use_special" == "true" ]]; then
        # Generate password with letters, numbers, and special characters
        PASSWORD=$(< /dev/urandom tr -dc 'A-Za-z0-9_@#$%&*!~' | head -c "$length")
    else
        # Generate password with letters and numbers only
        PASSWORD=$(< /dev/urandom tr -dc 'A-Za-z0-9' | head -c "$length")
    fi
    echo "$PASSWORD"
}

# Function to set a new password for a user
set_password() {
    local username="$1"
    local password="$2"
    echo "$username:$password" | sudo chpasswd
}

# Function to set expiration date for the user
set_expiration() {
    local username="$1"
    local expiration_minutes="$2"
    local expiration_date=$(date -d "+${expiration_minutes} minutes" +%Y-%m-%d" "%H:%M:%S)
    sudo chage -E "$expiration_date" "$username"
    echo "$expiration_date"
}

# Check if the user exists
if user_exists "$USERNAME"; then
    # Generate a password if not provided
    if [[ -z "$USER_PASSWORD" ]]; then
        USER_PASSWORD=$(generate_password "$PASSWORD_LENGTH" "$USE_SPECIAL")
    fi

    # Set the new password and expiration
    set_password "$USERNAME" "$USER_PASSWORD"
    EXPIRATION_DATE=$(set_expiration "$USERNAME" "$EXPIRATION_MINUTES")

    # Inform the user with the password in yellow
    YELLOW='\033[1;33m'  # Yellow color code
    RESET='\033[0m'      # Reset color code
    echo -e "Password for user '$USERNAME' has been set to '${YELLOW}$USER_PASSWORD${RESET}' and will expire in $EXPIRATION_MINUTES minutes on '$EXPIRATION_DATE'."
else
    exit 1
fi