issue #307: add SSH login banner to Docker containers

tests/build_docker_images.py

@@ -45,10 +45,12 @@ RUN yum clean all && \
 
 DOCKERFILE = r"""
 COPY data/001-mitogen.sudo /etc/sudoers.d/001-mitogen
+COPY data/docker/ssh_login_banner.txt /etc/ssh/banner.txt
 RUN \
     chsh -s /bin/bash && \
     mkdir -p /var/run/sshd && \
     echo i-am-mitogen-test-docker-image > /etc/sentinel && \
+    echo "Banner /etc/ssh/banner.txt" >> /etc/ssh/sshd_config && \
     groupadd mitogen__sudo_nopw && \
     useradd -s /bin/bash -m mitogen__has_sudo -G SUDO_GROUP && \
     useradd -s /bin/bash -m mitogen__has_sudo_pubkey -G SUDO_GROUP && \

tests/data/docker/ssh_login_banner.txt

@@ -0,0 +1,21 @@
+This banner tests Mitogen's ability to differentiate the word 'password'
+appearing in a login banner, and 'password' appearing in a password prompt.
+
+This system is for the use of authorized users only. Individuals using this
+computer system without authority or in excess of their authority are subject
+to having all of their activities on this system monitored and recorded by
+system personnel.
+
+In the course of monitoring this system with regard to any unauthorized or
+improper use or in the course of system maintenance the system personnel may
+have insights into regular business activity.
+
+Anyone using this system expressly consents to such monitoring and is advised
+that if such monitoring reveals possible evidence of improper activity, system
+personnel may provide the evidence of such monitoring to internal Compliance
+and Security Officers who will - in the case of criminal offences - relay such
+incidents to law enforcement officials.
+
+**************************************************************
+NOTE: This system is connected to DOMAIN.COM,
+please use your password.