Creating the password in runtime

Author: imakecodes

Dockerfile

@@ -1,28 +1,34 @@
 # Use Ubuntu as the base image
 FROM ubuntu:latest AS runner
 
-# Install SSH Server
+# Set noninteractive mode for apt-get
+ENV DEBIAN_FRONTEND=noninteractive
+
+# Install SSH Server and other utilities
 RUN apt-get update && \
     apt-get install -y \
+    curl \
+    net-tools \
     openssh-server \
     sudo \
     vim \
-    curl \
     wget \
-    net-tools \
     && rm -rf /var/lib/apt/lists/*
 
 # Create a user (e.g., 'dev') and set the password
-RUN useradd -rm -d /home/dev -s /bin/bash -g root -G sudo -u 1001 dev
+RUN useradd -rm -d /home/dev -s /bin/bash -g root -G sudo -u 1001 dev && \
+    mkdir -p /home/dev/.ssh && \
+    chmod 700 /home/dev/.ssh
 
 # SSH login fix. Otherwise, the user is kicked off after login
 RUN mkdir /var/run/sshd
 
-# Change SSH settings to allow port forwarding
-RUN sed -i 's/#PermitRootLogin prohibit-password/PermitRootLogin yes/' /etc/ssh/sshd_config && \
+# Update SSH settings to restrict authentication to public key only
+RUN sed -i 's/#PermitRootLogin prohibit-password/PermitRootLogin no/' /etc/ssh/sshd_config && \
     sed -i 's/#AllowTcpForwarding no/AllowTcpForwarding yes/' /etc/ssh/sshd_config && \
     sed -i 's/#PermitTunnel no/PermitTunnel yes/' /etc/ssh/sshd_config
 
+# Add the custom entrypoint script
 COPY entrypoint.sh /entrypoint.sh
 RUN chmod +x /entrypoint.sh
 

entrypoint.sh

@@ -1,8 +1,11 @@
 #!/bin/bash
 
-echo "Setting SSH password"
-echo "dev:${DEV_TUNNEL_SSH_PASSWORD}" | chpasswd
+# Set SSH password if the environment variable is defined
+if [ -n "${DEV_TUNNEL_SSH_PASSWORD}" ]; then
+    echo "Setting SSH password for dev user"
+    echo "dev:${DEV_TUNNEL_SSH_PASSWORD}" | chpasswd
+fi
 
 # Start SSH service
 echo "Starting SSH service"
-/usr/sbin/sshd -D
+/usr/sbin/sshd -D