1 files changed, 326 insertions, 0 deletions

diff --git a/debian/openssh-server.postinst b/debian/openssh-server.postinst
new file mode 100644
index 000000000..94461083e
--- /dev/null
+++ b/debian/openssh-server.postinst
@@ -0,0 +1,326 @@
+#!/bin/sh -e
+
+action="$1"
+oldversion="$2"
+
+. /usr/share/debconf/confmodule
+db_version 2.0
+
+umask 022
+
+
+get_config_option() {
+        option="$1"
+
+        [ -f /etc/ssh/sshd_config ] || return
+
+        # TODO: actually only one '=' allowed after option
+        perl -lne 's/\s+/ /g; print if s/^\s*'"$option"'[[:space:]=]+//i' \
+           /etc/ssh/sshd_config
+}
+
+
+set_config_option() {
+        option="$1"
+        value="$2"
+
+        perl -le '
+                $option = $ARGV[0]; $value = $ARGV[1]; $done = 0;
+                while (<STDIN>) {
+                        chomp;
+                        (my $match = $_) =~ s/\s+/ /g;
+                        if ($match =~ s/^\s*\Q$option\E\s+.*/$option $value/) {
+                                $_ = $match;
+                                $done = 1;
+                        }
+                        print;
+                }
+                print "$option $value" unless $done;' \
+                "$option" "$value" \
+                < /etc/ssh/sshd_config > /etc/ssh/sshd_config.dpkg-new
+        chown --reference /etc/ssh/sshd_config /etc/ssh/sshd_config.dpkg-new
+        chmod --reference /etc/ssh/sshd_config /etc/ssh/sshd_config.dpkg-new
+        mv /etc/ssh/sshd_config.dpkg-new /etc/ssh/sshd_config
+}
+
+
+rename_config_option() {
+        oldoption="$1"
+        newoption="$2"
+
+        value="$(get_config_option "$oldoption")"
+        [ "$value" ] || return 0
+
+        perl -le '
+                $oldoption = $ARGV[0]; $newoption = $ARGV[1];
+                while (<STDIN>) {
+                        chomp;
+                        (my $match = $_) =~ s/\s+/ /g;
+                        # TODO: actually only one "=" allowed after option
+                        if ($match =~ s/^(\s*)\Q$oldoption\E([[:space:]=]+)/$1$newoption$2/i) {
+                                $_ = $match;
+                        }
+                        print;
+                }' \
+                "$oldoption" "$newoption" \
+                < /etc/ssh/sshd_config > /etc/ssh/sshd_config.dpkg-new
+        chown --reference /etc/ssh/sshd_config /etc/ssh/sshd_config.dpkg-new
+        chmod --reference /etc/ssh/sshd_config /etc/ssh/sshd_config.dpkg-new
+        mv /etc/ssh/sshd_config.dpkg-new /etc/ssh/sshd_config
+}
+
+
+host_keys_required() {
+        hostkeys="$(get_config_option HostKey)"
+        if [ "$hostkeys" ]; then
+                echo "$hostkeys"
+        else
+                # No HostKey directives at all, so the server picks some
+                # defaults depending on the setting of Protocol.
+                protocol="$(get_config_option Protocol)"
+                [ "$protocol" ] || protocol=1,2
+                if echo "$protocol" | grep 1 >/dev/null; then
+                        echo /etc/ssh/ssh_host_key
+                fi
+                if echo "$protocol" | grep 2 >/dev/null; then
+                        echo /etc/ssh/ssh_host_rsa_key
+                        echo /etc/ssh/ssh_host_dsa_key
+                        echo /etc/ssh/ssh_host_ecdsa_key
+                fi
+        fi
+}
+
+
+create_key() {
+        msg="$1"
+        shift
+        hostkeys="$1"
+        shift
+        file="$1"
+        shift
+
+        if echo "$hostkeys" | grep -x "$file" >/dev/null && \
+           [ ! -f "$file" ] ; then
+                echo -n $msg
+                ssh-keygen -q -f "$file" -N '' "$@"
+                echo
+                if which restorecon >/dev/null 2>&1; then
+                        restorecon "$file.pub"
+                fi
+        fi
+}
+
+
+create_keys() {
+        hostkeys="$(host_keys_required)"
+
+        create_key "Creating SSH1 key; this may take some time ..." \
+                "$hostkeys" /etc/ssh/ssh_host_key -t rsa1
+
+        create_key "Creating SSH2 RSA key; this may take some time ..." \
+                "$hostkeys" /etc/ssh/ssh_host_rsa_key -t rsa
+        create_key "Creating SSH2 DSA key; this may take some time ..." \
+                "$hostkeys" /etc/ssh/ssh_host_dsa_key -t dsa
+        create_key "Creating SSH2 ECDSA key; this may take some time ..." \
+                "$hostkeys" /etc/ssh/ssh_host_ecdsa_key -t ecdsa
+}
+
+
+vulnerable_host_keys() {
+        # If the admin has explicitly put the vulnerable keys back, we
+        # assume they can look after themselves.
+        db_fget ssh/vulnerable_host_keys seen
+        if [ "$RET" = true ]; then
+                return 0
+        fi
+
+        hostkeys="$(host_keys_required)"
+        vulnerable=
+        for hostkey in $hostkeys; do
+                [ -f "$hostkey" ] || continue
+                if ssh-vulnkey -q "$hostkey"; then
+                        vulnerable="${vulnerable:+$vulnerable }$hostkey"
+                fi
+        done
+        if [ "$vulnerable" ]; then
+                db_subst ssh/vulnerable_host_keys HOST_KEYS "$vulnerable"
+                db_input critical ssh/vulnerable_host_keys || true
+                db_go
+                for hostkey in $vulnerable; do
+                        mv "$hostkey" "$hostkey.broken" || true
+                        mv "$hostkey.pub" "$hostkey.pub.broken" || true
+                done
+                create_keys
+        fi
+}
+
+
+fix_loglevel_silent() {
+        if [ "$(get_config_option LogLevel)" = SILENT ]; then
+                set_config_option LogLevel QUIET
+        fi
+}
+
+
+create_sshdconfig() {
+        if [ -e /etc/ssh/sshd_config ] ; then
+            # Upgrade an existing sshd configuration.
+
+            # This option was renamed in 3.8p1, but we never took care
+            # of adjusting the configuration file until now.
+            if dpkg --compare-versions "$oldversion" lt 1:4.7p1-8; then
+                rename_config_option KeepAlive TCPKeepAlive
+            fi
+
+            # 'LogLevel SILENT' is now equivalent to QUIET.
+            if dpkg --compare-versions "$oldversion" lt 1:5.4p1-1; then
+                fix_loglevel_silent
+            fi
+
+            return 0
+        fi
+
+        cat <<EOF > /etc/ssh/sshd_config
+# Package generated configuration file
+# See the sshd_config(5) manpage for details
+
+# What ports, IPs and protocols we listen for
+Port 22
+# Use these options to restrict which interfaces/protocols sshd will bind to
+#ListenAddress ::
+#ListenAddress 0.0.0.0
+Protocol 2
+# HostKeys for protocol version 2
+HostKey /etc/ssh/ssh_host_rsa_key
+HostKey /etc/ssh/ssh_host_dsa_key
+HostKey /etc/ssh/ssh_host_ecdsa_key
+#Privilege Separation is turned on for security
+UsePrivilegeSeparation yes
+
+# Lifetime and size of ephemeral version 1 server key
+KeyRegenerationInterval 3600
+ServerKeyBits 768
+
+# Logging
+SyslogFacility AUTH
+LogLevel INFO
+
+# Authentication:
+LoginGraceTime 120
+PermitRootLogin yes
+StrictModes yes
+
+RSAAuthentication yes
+PubkeyAuthentication yes
+#AuthorizedKeysFile     %h/.ssh/authorized_keys
+
+# Don't read the user's ~/.rhosts and ~/.shosts files
+IgnoreRhosts yes
+# For this to work you will also need host keys in /etc/ssh_known_hosts
+RhostsRSAAuthentication no
+# similar for protocol version 2
+HostbasedAuthentication no
+# Uncomment if you don't trust ~/.ssh/known_hosts for RhostsRSAAuthentication
+#IgnoreUserKnownHosts yes
+
+# To enable empty passwords, change to yes (NOT RECOMMENDED)
+PermitEmptyPasswords no
+
+# Change to yes to enable challenge-response passwords (beware issues with
+# some PAM modules and threads)
+ChallengeResponseAuthentication no
+
+# Change to no to disable tunnelled clear text passwords
+#PasswordAuthentication yes
+
+# Kerberos options
+#KerberosAuthentication no
+#KerberosGetAFSToken no
+#KerberosOrLocalPasswd yes
+#KerberosTicketCleanup yes
+
+# GSSAPI options
+#GSSAPIAuthentication no
+#GSSAPICleanupCredentials yes
+
+X11Forwarding yes
+X11DisplayOffset 10
+PrintMotd no
+PrintLastLog yes
+TCPKeepAlive yes
+#UseLogin no
+
+#MaxStartups 10:30:60
+#Banner /etc/issue.net
+
+# Allow client to pass locale environment variables
+AcceptEnv LANG LC_*
+
+Subsystem sftp /usr/lib/openssh/sftp-server
+
+# Set this to 'yes' to enable PAM authentication, account processing,
+# and session processing. If this is enabled, PAM authentication will
+# be allowed through the ChallengeResponseAuthentication and
+# PasswordAuthentication.  Depending on your PAM configuration,
+# PAM authentication via ChallengeResponseAuthentication may bypass
+# the setting of "PermitRootLogin without-password".
+# If you just want the PAM account and session checks to run without
+# PAM authentication, then enable this but set PasswordAuthentication
+# and ChallengeResponseAuthentication to 'no'.
+UsePAM yes
+EOF
+}
+
+fix_statoverride() {
+# Remove an erronous override for sshd (we should have overridden ssh)
+        if [ -x /usr/sbin/dpkg-statoverride ]; then
+                if dpkg-statoverride --list /usr/sbin/sshd >/dev/null ; then
+                        dpkg-statoverride --remove /usr/sbin/sshd
+                fi
+        fi
+}
+
+setup_sshd_user() {
+        if ! getent passwd sshd >/dev/null; then
+                adduser --quiet --system --no-create-home --home /var/run/sshd --shell /usr/sbin/nologin sshd
+        fi
+}
+
+remove_old_init_links() {
+        # Yes, this only works with the SysV init script layout. I know.
+        # The important thing is that it doesn't actually *break* with
+        # file-rc ...
+        if [ -e /etc/rc2.d/S20ssh ]; then
+                update-rc.d -f ssh remove >/dev/null 2>&1
+        fi
+        rm -f /etc/rc0.d/K??ssh /etc/rc1.d/K??ssh /etc/rc6.d/K??ssh
+}
+
+if [ "$action" = configure ]; then
+        create_sshdconfig
+        create_keys
+        vulnerable_host_keys
+        fix_statoverride
+        setup_sshd_user
+        if dpkg --compare-versions "$2" lt 1:5.2p1-1; then
+            remove_old_init_links
+        fi
+        # Renamed to /etc/ssh/moduli in 2.9.9 (!)
+        if dpkg --compare-versions "$2" lt 1:4.7p1-1; then
+            rm -f /etc/ssh/primes
+        fi
+        if dpkg --compare-versions "$2" lt 1:5.5p1-6; then
+            rm -f /var/run/sshd/.placeholder
+        fi
+
+        # Clean up old debconf templates.
+        db_unregister ssh/use_old_init_script
+        db_unregister ssh/encrypted_host_key_but_no_keygen
+        db_unregister ssh/disable_cr_auth
+fi
+
+#DEBHELPER#
+
+db_stop
+
+exit 0