#!/bin/bash
#
# .---.                  .              .
# |                      |              |
# |--- .--. .-.  .-.  .-.|  .-. .--.--. |.-.  .-. .--.  .-.
# |    |   (.-' (.-' (   | (   )|  |  | |   )(   )|  | (.-'
# '    '     --'  --'  -' -  -' '  '   -' -'   -' '   -  --'
#
#                    Freedom in the Cloud
#
# SIP functions
#
# License
# =======
#
# Copyright (C) 2014-2016 Bob Mottram <bob@freedombone.net>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

VARIANTS='full full-vim chat'

IN_DEFAULT_INSTALL=1
SHOW_ON_ABOUT=1

SIP_SERVER_PASSWORD=
SIP_PORT=5060
SIP_TLS_PORT=5061

TURN_PORT=3478
TURN_TLS_PORT=5349
TURN_NONCE=

sip_variables=(ONION_ONLY
               MY_USERNAME
               SIP_PORT
               SIP_TLS_PORT
               SIP_SERVER_PASSWORD
               TURN_PORT
               TURN_TLS_PORT
               TURN_NONCE)

function remove_user_sip {
    remove_username="$1"
    ${PROJECT_NAME}-rmsipuser ${remove_username}

    # remove user from SIP TURN/STUN
    if [ -f /etc/turnserver/turnusers.txt ]; then
        sed -i "/${remove_username}:/d" /etc/turnserver/turnusers.txt
    fi
}

function add_user_sip {
    new_username="$1"
    new_user_password="$2"

    SIP_EXTENSION=$(${PROJECT_NAME}-sipfreeext)
    ${PROJECT_NAME}-addsipuser -u $new_username -e $SIP_EXTENSION -p "$new_user_password"
    if [ ! "$?" = "0" ]; then
        echo '1'
        return
    fi

    # add user to the sipwitch group
    if [ -f /etc/sipwitch.conf ]; then
        usermod -aG sipwitch $new_username
    fi

    # add user for SIP STUN/TURN
    if [ -d /etc/turnserver ]; then
        if grep -q "DEFAULT_DOMAIN_NAME" $CONFIGURATION_FILE; then
            read_config_param "DEFAULT_DOMAIN_NAME"
            echo "${new_username}:${new_user_password}:${DEFAULT_DOMAIN_NAME}:authorized" >> /etc/turnserver/turnusers.txt
        fi
    fi

    echo '0'
}

function install_interactive_sip {
    echo -n ''
    APP_INSTALLED=1
}

function change_password_sip {
    echo -n ''
}

function reconfigure_sip {
    echo -n ''
}

function upgrade_sip {
    # remove the original sipwitch daemon if it exists
    if [ -f /etc/init.d/sipwitch ]; then
        rm -f /etc/init.d/sipwitch
    fi
}

function backup_local_sip {
    if [ -f /etc/sipwitch.conf ]; then
        echo $"Backing up SIP settings"
        temp_backup_dir=/root/tempsipbackup
        if [ ! -d $temp_backup_dir ]; then
            mkdir -p $temp_backup_dir
        fi
        cp -f /etc/sipwitch.conf $temp_backup_dir
        backup_directory_to_usb $temp_backup_dir sip
        echo $"SIP settings backup complete"
    fi
}

function restore_local_sip {
    if [ -d $USB_MOUNT/backup/sip ]; then
        echo $"Restoring SIP settings"
        temp_restore_dir=/root/tempsip
        function_check restore_directory_from_usb
        restore_directory_from_usb $temp_restore_dir sip
        cp -f $temp_restore_dir/home/$ADMIN_USERNAME/tempbackup/sipwitch.conf /etc/sipwitch.conf
        if [ ! "$?" = "0" ]; then
            rm -rf $temp_restore_dir
            function_check set_user_permissions
            set_user_permissions
            backup_unmount_drive
            exit 3679
        fi
        rm -rf $temp_restore_dir
        service sipwitch restart
        echo $"Restore of SIP settings complete"
    fi
}

function backup_remote_sip {
    if [ -f /etc/sipwitch.conf ]; then
        echo $"Backing up SIP settings"
        temp_backup_dir=/root/tempsipbackup
        if [ ! -d $temp_backup_dir ]; then
            mkdir -p $temp_backup_dir
        fi
        cp -f /etc/sipwitch.conf $temp_backup_dir
        backup_directory_to_friend $temp_backup_dir sip
        echo $"Backup SIP settings complete"
    fi
}

function restore_remote_sip {
    echo -n ''
}

function remove_sip {
    firewall_remove ${TURN_PORT}
    firewall_remove ${TURN_TLS_PORT} tcp
    firewall_remove ${SIP_PORT}
    firewall_remove ${SIP_TLS_PORT}

    function_check remove_onion_service
    remove_onion_service sip ${SIP_PORT}

    apt-get -yq remove --purge sipwitch
    apt-get -yq remove --purge turnserver
    if [ -f /etc/sipwitch.conf ]; then
        rm /etc/sipwitch.conf
    fi
    if [ -d /etc/turnserver ]; then
        rm -rf /etc/turnserver
    fi
    remove_completion_param install_sip
    remove_completion_param configure_firewall_for_turn
    remove_completion_param configure_firewall_for_sip4
    sed -i '/SIP /d' /home/$MY_USERNAME/README
}

function configure_firewall_for_turn {
    if [[ $(is_completed $FUNCNAME) == "1" ]]; then
        return
    fi
    if [[ $ONION_ONLY != "no" ]]; then
        return
    fi
    firewall_add TURN ${TURN_PORT}
    firewall_add "TURN TLS" ${TURN_TLS_PORT} tcp
    mark_completed $FUNCNAME
}


function configure_firewall_for_sip4 {
    if [[ $(is_completed $FUNCNAME) == "1" ]]; then
        return
    fi
    if [[ $ONION_ONLY != "no" ]]; then
        return
    fi
    firewall_add SIP ${SIP_PORT}
    firewall_add "SIP TLS" ${SIP_TLS_PORT}
    mark_completed $FUNCNAME
}

function get_sip_server_password {
    if [ -f /home/$MY_USERNAME/README ]; then
        if grep -q "sip server password" /home/$MY_USERNAME/README; then
            if [ ! $SIP_SERVER_PASSWORD ]; then
                SIP_SERVER_PASSWORD=$(cat /home/$MY_USERNAME/README | grep "sip server password" | awk -F ':' '{print $2}' | sed 's/^ *//')
            fi
        fi
    fi
}

function update_sipwitch_daemon {
    if [ ! -f /etc/init.d/sipwitch ]; then
        return
    fi

    service sipwitch stop

    # remove the original sipwitch daemon if it exists
    if [ -f /etc/init.d/sipwitch ]; then
        rm -f /etc/init.d/sipwitch
    fi

    # daemon
    echo '[Unit]' > /etc/systemd/system/sipwitch.service
    echo 'Description=GNU SIP Witch, a SIP telephony service daemon.' >> /etc/systemd/system/sipwitch.service
    echo 'After=network.target' >> /etc/systemd/system/sipwitch.service
    echo '' >> /etc/systemd/system/sipwitch.service
    echo '[Service]' >> /etc/systemd/system/sipwitch.service
    echo 'Type=simple' >> /etc/systemd/system/sipwitch.service
    echo 'Group=sipwitch' >> /etc/systemd/system/sipwitch.service
    echo 'PIDFile=/var/run/sipwitch/pidfile' >> /etc/systemd/system/sipwitch.service
    echo 'EnvironmentFile=-/etc/conf.d/sipwitch' >> /etc/systemd/system/sipwitch.service
    echo 'EnvironmentFile=-/etc/sipwitch.conf' >> /etc/systemd/system/sipwitch.service
    echo 'EnvironmentFile=-/etc/default/sipwitch' >> /etc/systemd/system/sipwitch.service
    echo 'ExecStartPre=-/bin/rm -f /var/run/sipwitch/control' >> /etc/systemd/system/sipwitch.service
    echo "ExecStart=/usr/sbin/sipw -f \$OPTIONS -P$SIP_PORT" >> /etc/systemd/system/sipwitch.service
    echo 'Restart=always' >> /etc/systemd/system/sipwitch.service
    echo 'NotifyAccess=main' >> /etc/systemd/system/sipwitch.service
    echo '' >> /etc/systemd/system/sipwitch.service
    echo '[Install]' >> /etc/systemd/system/sipwitch.service
    echo 'WantedBy=multi-user.target' >> /etc/systemd/system/sipwitch.service

    systemctl enable sipwitch
    systemctl daemon-reload
    systemctl start sipwitch
}

function install_sip_main {
    if [[ $(app_is_installed sip_main) == "1" ]]; then
        return
    fi

    apt-get -yq install sipwitch

    function_check get_sip_server_password
    get_sip_server_password
    if [ ! $SIP_SERVER_PASSWORD ]; then
        if [ -f $IMAGE_PASSWORD_FILE ]; then
            SIP_SERVER_PASSWORD="$(printf `cat $IMAGE_PASSWORD_FILE`)"
        else
            SIP_SERVER_PASSWORD="$(create_password ${MINIMUM_PASSWORD_LENGTH})"
        fi
    fi

    echo '<?xml version="1.0"?>' > /etc/sipwitch.conf
    echo '<sipwitch>' >> /etc/sipwitch.conf
    echo '<provision>' >> /etc/sipwitch.conf

    echo "<user id=\"$MY_USERNAME\">" >> /etc/sipwitch.conf
    echo '<extension>201</extension>' >> /etc/sipwitch.conf
    echo "<secret>$SIP_SERVER_PASSWORD</secret>" >> /etc/sipwitch.conf
    echo "<display>$MY_USERNAME 201</display>" >> /etc/sipwitch.conf
    echo '</user>' >> /etc/sipwitch.conf

    echo '</provision>' >> /etc/sipwitch.conf
    echo '<access>' >> /etc/sipwitch.conf
    echo '</access>' >> /etc/sipwitch.conf
    echo '<stack>' >> /etc/sipwitch.conf
    echo "  <localnames>$DEFAULT_DOMAIN_NAME</localnames>" >> /etc/sipwitch.conf
    echo '  <mapped>200</mapped>' >> /etc/sipwitch.conf
    echo '  <threading>2</threading>' >> /etc/sipwitch.conf
    echo '  <interface>*</interface>' >> /etc/sipwitch.conf
    echo '  <dumping>false</dumping>' >> /etc/sipwitch.conf
    echo '  <system>system</system>' >> /etc/sipwitch.conf
    echo '  <anon>anonymous</anon>' >> /etc/sipwitch.conf
    echo '</stack>' >> /etc/sipwitch.conf
    echo '<timers>' >> /etc/sipwitch.conf
    echo '  <!-- ring every 4 seconds -->' >> /etc/sipwitch.conf
    echo '  <ring>4</ring>' >> /etc/sipwitch.conf
    echo '  <!-- call forward no answer after x rings -->' >> /etc/sipwitch.conf
    echo '  <cfna>4</cfna>' >> /etc/sipwitch.conf
    echo '  <!-- call reset to clear cid in stack, 6 seconds -->' >> /etc/sipwitch.conf
    echo '  <reset>6</reset>' >> /etc/sipwitch.conf
    echo '</timers>' >> /etc/sipwitch.conf
    echo '<!-- we have 2xx numbers plus space for external users -->' >> /etc/sipwitch.conf
    echo '<registry>' >> /etc/sipwitch.conf
    echo '  <prefix>200</prefix>' >> /etc/sipwitch.conf
    echo '  <range>100</range>' >> /etc/sipwitch.conf
    echo '  <keysize>77</keysize>' >> /etc/sipwitch.conf
    echo '  <mapped>200</mapped>' >> /etc/sipwitch.conf
    echo '  <!-- <realm>GNU Telephony</realm> -->' >> /etc/sipwitch.conf
    echo '</registry>' >> /etc/sipwitch.conf
    echo '<routing>' >> /etc/sipwitch.conf
    echo '</routing>' >> /etc/sipwitch.conf
    echo '</sipwitch>' >> /etc/sipwitch.conf

    sed -i 's|#PLUGINS=|PLUGINS=|g' /etc/default/sipwitch
    sed -i 's|PLUGINS=.*|PLUGINS="zeroconf subscriber forward"|g' /etc/default/sipwitch
    groupadd sipwitch
    usermod -aG sipwitch $MY_USERNAME

    SIP_ONION_HOSTNAME=$(add_onion_service sip ${SIP_PORT} ${SIP_PORT})

    if ! grep -q $"SIP Server" /home/$MY_USERNAME/README; then
        echo '' >> /home/$MY_USERNAME/README
        echo '' >> /home/$MY_USERNAME/README
        echo $'# SIP Server' >> /home/$MY_USERNAME/README
        echo $"SIP onion_domain: $SIP_ONION_HOSTNAME" >> /home/$MY_USERNAME/README
        echo $"SIP server username: $MY_USERNAME" >> /home/$MY_USERNAME/README
        echo $"SIP server extension: 201" >> /home/$MY_USERNAME/README
        echo $"SIP server password: $SIP_SERVER_PASSWORD" >> /home/$MY_USERNAME/README
        chown $MY_USERNAME:$MY_USERNAME /home/$MY_USERNAME/README
        chmod 600 /home/$MY_USERNAME/README
    fi

    function_check configure_firewall_for_sip4
    configure_firewall_for_sip4
    install_completed sip_main
}

function install_sip_turn {
    if [[ $(app_is_installed sip_turn) == "1" ]]; then
        return
    fi

    apt-get -yq install turnserver

    # create a nonce if needed
    if [ ! $TURN_NONCE ]; then
        TURN_NONCE="$(create_password 30)"
    fi

    function_check create_site_certificate
    create_site_certificate $DEFAULT_DOMAIN_NAME

    echo '##' > /etc/turnserver/turnserver.conf
    echo '# TurnServer configuration file.' >> /etc/turnserver/turnserver.conf
    echo '#' >> /etc/turnserver/turnserver.conf
    echo '' >> /etc/turnserver/turnserver.conf
    echo '## Public IPv4 address of any relayed address (if not set, no relay for IPv4).' >> /etc/turnserver/turnserver.conf
    echo '## To have multiple address, separate addresses with a comma' >> /etc/turnserver/turnserver.conf
    echo '## (i.e. listen_address = { "172.16.0.1", "172.17.0.1" }).' >> /etc/turnserver/turnserver.conf
    echo "listen_address = { \"192.168.0.1\" }" >> /etc/turnserver/turnserver.conf
    echo '' >> /etc/turnserver/turnserver.conf
    echo '## Public IPv6 address of any relayed address (if not set, no relay for IPv6).' >> /etc/turnserver/turnserver.conf
    echo '## To have multiple address, separate address with a comma' >> /etc/turnserver/turnserver.conf
    echo '## (i.e. listen_addressv6 = { "2001:db8:1::1", "2001:db8:2::1" }).' >> /etc/turnserver/turnserver.conf
    echo "#listen_addressv6 = { \"2001:db8::1\" }" >> /etc/turnserver/turnserver.conf
    echo '' >> /etc/turnserver/turnserver.conf
    echo '## UDP listening port.' >> /etc/turnserver/turnserver.conf
    echo "udp_port = $TURN_PORT" >> /etc/turnserver/turnserver.conf
    echo '' >> /etc/turnserver/turnserver.conf
    echo '## TCP listening port.' >> /etc/turnserver/turnserver.conf
    echo "tcp_port = $TURN_PORT" >> /etc/turnserver/turnserver.conf
    echo '' >> /etc/turnserver/turnserver.conf
    echo '## TLS listening port.' >> /etc/turnserver/turnserver.conf
    echo "tls_port = $TURN_TLS_PORT" >> /etc/turnserver/turnserver.conf
    echo '' >> /etc/turnserver/turnserver.conf
    echo '## TLS support.' >> /etc/turnserver/turnserver.conf
    echo 'tls = true' >> /etc/turnserver/turnserver.conf
    echo '' >> /etc/turnserver/turnserver.conf
    echo '## DTLS support. It is an experimental feature and is not defined in TURN' >> /etc/turnserver/turnserver.conf
    echo '## standard.' >> /etc/turnserver/turnserver.conf
    echo 'dtls = false' >> /etc/turnserver/turnserver.conf
    echo '' >> /etc/turnserver/turnserver.conf
    echo '## Maximum allocation port number.' >> /etc/turnserver/turnserver.conf
    echo 'max_port = 65535' >> /etc/turnserver/turnserver.conf
    echo '' >> /etc/turnserver/turnserver.conf
    echo '## Minimum allocation port number.' >> /etc/turnserver/turnserver.conf
    echo '' >> /etc/turnserver/turnserver.conf
    echo 'min_port = 49152' >> /etc/turnserver/turnserver.conf
    echo '' >> /etc/turnserver/turnserver.conf
    echo '## TURN-TCP support.' >> /etc/turnserver/turnserver.conf
    echo '' >> /etc/turnserver/turnserver.conf
    echo 'turn_tcp = true' >> /etc/turnserver/turnserver.conf
    echo '' >> /etc/turnserver/turnserver.conf
    echo '## TURN-TCP buffering mode:' >> /etc/turnserver/turnserver.conf
    echo '## - true, use userspace buffering;' >> /etc/turnserver/turnserver.conf
    echo '## - false, use kernel buffering.' >> /etc/turnserver/turnserver.conf
    echo 'tcp_buffer_userspace = true' >> /etc/turnserver/turnserver.conf
    echo '' >> /etc/turnserver/turnserver.conf
    echo '## TURN-TCP maximum buffer size.' >> /etc/turnserver/turnserver.conf
    echo 'tcp_buffer_size = 32768' >> /etc/turnserver/turnserver.conf
    echo '' >> /etc/turnserver/turnserver.conf
    echo '## Daemon mode.' >> /etc/turnserver/turnserver.conf
    echo 'daemon = true' >> /etc/turnserver/turnserver.conf
    echo '' >> /etc/turnserver/turnserver.conf
    echo '## Unprivileged user.' >> /etc/turnserver/turnserver.conf
    echo '## If you want to use this feature create a system user.' >> /etc/turnserver/turnserver.conf
    echo '## On Linux: adduser --system --group turnserver' >> /etc/turnserver/turnserver.conf
    echo 'unpriv_user = turnserver' >> /etc/turnserver/turnserver.conf
    echo '' >> /etc/turnserver/turnserver.conf
    echo '## Realm value.' >> /etc/turnserver/turnserver.conf
    echo "realm = \"$DEFAULT_DOMAIN_NAME\"" >> /etc/turnserver/turnserver.conf
    echo '' >> /etc/turnserver/turnserver.conf
    echo '## Nonce key.' >> /etc/turnserver/turnserver.conf
    echo "nonce_key = \"$TURN_NONCE\"" >> /etc/turnserver/turnserver.conf
    echo '' >> /etc/turnserver/turnserver.conf
    echo '## Max relay per username.' >> /etc/turnserver/turnserver.conf
    echo 'max_relay_per_username = 5' >> /etc/turnserver/turnserver.conf
    echo '' >> /etc/turnserver/turnserver.conf
    echo '## Allocation lifetime.' >> /etc/turnserver/turnserver.conf
    echo 'allocation_lifetime = 1800' >> /etc/turnserver/turnserver.conf
    echo '' >> /etc/turnserver/turnserver.conf
    echo '## Allocation bandwidth limitation (in KBytes/s).' >> /etc/turnserver/turnserver.conf
    echo '## 0 value means bandwidth quota disabled.' >> /etc/turnserver/turnserver.conf
    echo 'bandwidth_per_allocation = 150' >> /etc/turnserver/turnserver.conf
    echo '' >> /etc/turnserver/turnserver.conf
    echo '## Restricted user bandwidth (in KBytes/s).' >> /etc/turnserver/turnserver.conf
    echo '## 0 value means bandwidth limitation disabled.' >> /etc/turnserver/turnserver.conf
    echo 'restricted_bandwidth = 10' >> /etc/turnserver/turnserver.conf
    echo '' >> /etc/turnserver/turnserver.conf
    echo '## Denied addresses.' >> /etc/turnserver/turnserver.conf
    echo '' >> /etc/turnserver/turnserver.conf
    echo '# disallow relaying to localhost' >> /etc/turnserver/turnserver.conf
    echo 'denied_address {' >> /etc/turnserver/turnserver.conf
    echo '  address = "127.0.0.1"' >> /etc/turnserver/turnserver.conf
    echo '  mask = "8"' >> /etc/turnserver/turnserver.conf
    echo '  port = 0' >> /etc/turnserver/turnserver.conf
    echo '}' >> /etc/turnserver/turnserver.conf
    echo '' >> /etc/turnserver/turnserver.conf
    echo '# disallow relaying to ip6-localhost' >> /etc/turnserver/turnserver.conf
    echo 'denied_address {' >> /etc/turnserver/turnserver.conf
    echo '  address = "::1"' >> /etc/turnserver/turnserver.conf
    echo '  mask = "128"' >> /etc/turnserver/turnserver.conf
    echo '  port = 0' >> /etc/turnserver/turnserver.conf
    echo '}' >> /etc/turnserver/turnserver.conf
    echo '' >> /etc/turnserver/turnserver.conf
    echo '## Certification Authority file.' >> /etc/turnserver/turnserver.conf
    echo "ca_file = \"/etc/ssl/certs/ca-certificates.crt\"" >> /etc/turnserver/turnserver.conf
    echo '' >> /etc/turnserver/turnserver.conf
    echo '## Server certificate file.' >> /etc/turnserver/turnserver.conf
    if [ -f /etc/ssl/certs/$DEFAULT_DOMAIN_NAME.pem ]; then
        echo "cert_file = \"/etc/ssl/certs/$DEFAULT_DOMAIN_NAME.pem\"" >> /etc/turnserver/turnserver.conf
    else
        if [ -f /etc/ssl/certs/$DEFAULT_DOMAIN_NAME.crt ]; then
            echo "cert_file = \"/etc/ssl/certs/$DEFAULT_DOMAIN_NAME.crt\"" >> /etc/turnserver/turnserver.conf
        fi
    fi
    echo '' >> /etc/turnserver/turnserver.conf
    echo '## Private key file.' >> /etc/turnserver/turnserver.conf
    echo "private_key_file = \"/etc/ssl/certs/$DEFAULT_DOMAIN_NAME.key\"" >> /etc/turnserver/turnserver.conf
    echo '' >> /etc/turnserver/turnserver.conf
    echo '## Account method.' >> /etc/turnserver/turnserver.conf
    echo "account_method = \"file\"" >> /etc/turnserver/turnserver.conf
    echo '' >> /etc/turnserver/turnserver.conf
    echo '## Account file (if account_method = file).' >> /etc/turnserver/turnserver.conf
    echo "account_file = \"/etc/turnserver/turnusers.txt\"" >> /etc/turnserver/turnserver.conf
    echo '' >> /etc/turnserver/turnserver.conf
    echo '## mod_tmpuser.' >> /etc/turnserver/turnserver.conf
    echo 'mod_tmpuser = false' >> /etc/turnserver/turnserver.conf

    echo "${MY_USERNAME}:password:${DEFAULT_DOMAIN_NAME}:authorized" > /etc/turnserver/turnusers.txt

    systemctl restart turnserver

    function_check configure_firewall_for_turn
    configure_firewall_for_turn
    install_completed sip_turn
}

function install_sip {
    install_sip_main
    update_sipwitch_daemon
    APP_INSTALLED=1
}

# NOTE: deliberately no exit 0