diff --git a/src/freedombone b/src/freedombone index eb9e0cb8..9cc118c4 100755 --- a/src/freedombone +++ b/src/freedombone @@ -226,10 +226,11 @@ SSL_PROTOCOLS="TLSv1 TLSv1.1 TLSv1.2" # list of ciphers to use. See bettercrypto.org recommendations SSL_CIPHERS="EDH+CAMELLIA:EDH+aRSA:EECDH+aRSA+AESGCM:EECDH+aRSA+SHA384:EECDH+aRSA+SHA256:EECDH:+CAMELLIA256:+AES256:+CAMELLIA128:+AES128:+SSLv3:!aNULL:!eNULL:!LOW:!3DES:!MD5:!EXP:!PSK:!DSS:!RC4:!SEED:!ECDSA:CAMELLIA256-SHA:AES256-SHA:CAMELLIA128-SHA:AES128-SHA" -# ssh ciphers -SSH_CIPHERS="aes256-gcm@openssh.com,aes128-gcm@openssh.com,aes256-ctr,aes128-ctr" -SSH_MACS="hmac-sha2-512-etm@openssh.com,hmac-sha2-256-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-512,hmac-sha2-256,hmac-ripemd160" -SSH_KEX="diffie-hellman-group-exchange-sha256,diffie-hellman-group14-sha1,diffie-hellman-group-exchange-sha1" +# ssh (from https://stribika.github.io/2015/01/04/secure-secure-shell.html) +SSH_CIPHERS="chacha20-poly1305@openssh.com,aes256-gcm@openssh.com,aes128-gcm@openssh.com,aes256-ctr,aes192-ctr,aes128-ctr" +SSH_MACS="hmac-sha2-512-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-ripemd160-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-512,hmac-sha2-256,hmac-ripemd160,umac-128@openssh.com" +SSH_KEX="curve25519-sha256@libssh.org,diffie-hellman-group-exchange-sha256" +SSH_HOST_KEY_ALGORITHMS="ssh-ed25519-cert-v01@openssh.com,ssh-rsa-cert-v01@openssh.com,ssh-rsa-cert-v00@openssh.com,ssh-ed25519,ssh-rsa" # xmpp ciphers and curve XMPP_CIPHERS='"EDH+CAMELLIA:EDH+aRSA:EECDH+aRSA+AESGCM:EECDH+aRSA+SHA256:EECDH:+CAMELLIA128:+AES128:+SSLv3:!aNULL:!eNULL:!LOW:!3DES:!MD5:!EXP:!PSK:!DSS:!RC4:!SEED:!IDEA:!ECDSA:kEDH:CAMELLIA128-SHA:AES128-SHA"' @@ -4256,12 +4257,48 @@ function configure_ssh { reboot } +# see https://stribika.github.io/2015/01/04/secure-secure-shell.html +function ssh_remove_small_moduli { + awk '$5 > 2000' /etc/ssh/moduli > ~/moduli + if [[ $((wc -l ~/moduli | awk -F ' ' '{print $1}')) < 150 ]]; then + echo 'Not enough moduli > 2000' + exit 57824 + fi + mv ~/moduli /etc/ssh/moduli +} + +function configure_ssh_client { + if grep -Fxq "configure_ssh_client" $COMPLETION_FILE; then + return + fi + #sed 's/# PasswordAuthentication.*/ PasswordAuthentication no/g' /etc/ssh/ssh_config + #sed 's/# ChallengeResponseAuthentication.*/ ChallengeResponseAuthentication no/g' /etc/ssh/ssh_config + sed "s/# HostKeyAlgorithms.*/ HostKeyAlgorithms $SSH_HOST_KEY_ALGORITHMS/g" /etc/ssh/ssh_config + sed "s/# Ciphers.*/ Ciphers $SSH_CIPHERS/g" /etc/ssh/ssh_config + sed "s/# MACs.*/ MACs $SSH_MACS/g" /etc/ssh/ssh_config + if ! grep -q "HostKeyAlgorithms" /etc/ssh/ssh_config; then + echo " HostKeyAlgorithms $SSH_HOST_KEY_ALGORITHMS" >> /etc/ssh/ssh_config + fi + sed "s/Ciphers.*/Ciphers $SSH_CIPHERS/g" /etc/ssh/ssh_config + if ! grep -q "Ciphers " /etc/ssh/ssh_config; then + echo " Ciphers $SSH_CIPHERS" >> /etc/ssh/ssh_config + fi + sed "s/MACs.*/MACs $SSH_MACS/g" /etc/ssh/ssh_config + if ! grep -q "MACs " /etc/ssh/ssh_config; then + echo " MACs $SSH_MACS" >> /etc/ssh/ssh_config + fi + ssh-keygen -t ed25519 -o -a 100 + ssh-keygen -t rsa -b 4096 -o -a 100 + echo 'configure_ssh_client' >> $COMPLETION_FILE +} + function regenerate_ssh_keys { if grep -Fxq "regenerate_ssh_keys" $COMPLETION_FILE; then return fi rm -f /etc/ssh/ssh_host_* dpkg-reconfigure openssh-server + ssh_remove_small_moduli service ssh restart echo 'regenerate_ssh_keys' >> $COMPLETION_FILE }