#!/bin/sh
# /etc/rc.d/rc655.siproxd - install siproxs
#------------------------------------------------------------------------------
#
# Creation:     2021-03-28  Christoph Fritsch <fli4l@dechristo.net>
# Last Update:  2021-03-29  Christoph Fritsch <fli4l@dechristo.net>
#------------------------------------------------------------------------------

SIPROX_CFG_DIR='/etc/siproxd'

###############################################################################
# Functions
###############################################################################

# joins strings with given divider
# $(join_by ',' a b c) ---> a,b,c
join_by ()
{
    local IFS="$1";
    shift;
    echo "$*"
}

###############################################################################
# Start script
###############################################################################

case $OPT_SIPROXD in
yes)
    begin_script SIPROXD "setting up siproxd SIP Proxy..."
    
    log_info "creating siproxd config directory $SIPROX_CFG_DIR"
    mkdir -p $SIPROX_CFG_DIR


    # Prepare siproxd server config in $SIPROX_CFG_DIR 
    for siproxd_config_idx in $(seq 1 $SIPROXD_N)
    do
        eval local siproxd_dev_in='$SIPROXD_'$siproxd_config_idx'_DEV_IN'
        # translate IP_NET_1_DEV, eth0.100
        translate_net_if $siproxd_dev_in siproxd_dev_in
        log_info "siproxd input interface $siproxd_dev_in..."
        
        eval local siproxd_dev_out='$SIPROXD_'$siproxd_config_idx'_DEV_OUT'
        # translate IP_NET_1_DEV, eth0.100
        translate_net_if $siproxd_dev_out siproxd_dev_out
        log_info "siproxd output interface $siproxd_dev_out..."

        eval local siproxd_listen_port='$SIPROXD_'$siproxd_config_idx'_SIP_PORT'
        eval local siproxd_rtp_port_min='$SIPROXD_'$siproxd_config_idx'_RTP_PORT_MIN'
        eval local siproxd_rtp_port_max='$SIPROXD_'$siproxd_config_idx'_RTP_PORT_MAX'
        
        eval local siproxd_transparent='$SIPROXD_'$siproxd_config_idx'_TRANSPARENT'
        
        # concat allowed nets, translate IP_NET_x and {prefixes} to IPs and write to config file
        siproxd_allowed_nets=''
        eval local allowed_nets_n='$SIPROXD_'$siproxd_config_idx'_ALLOW_REG_N'
        for allowed_nets_idx in $(seq 1 $allowed_nets_n)
        do
            eval local allowed_net='$SIPROXD_'$siproxd_config_idx'_ALLOW_REG_'$allowed_nets_idx
            log_info "processing allowed_net $allowed_net..."
            local res=$allowed_net
            case $allowed_net in
            IP_NET_*)
                translate_ip_net $allowed_net SIPROXD_${siproxd_config_idx}_ALLOW_REG_${allowed_nets_idx}
                allowed_net=$res
                log_info "translated IP_NET_*..."
                ;;
            IPV6_NET_*)
                translate_ip6_net $allowed_net SIPROXD_${siproxd_config_idx}_ALLOW_REG_${allowed_nets_idx}
                allowed_net=$res
                log_info "translated IPV6_NET_*..."
                ;;
            {*})
                # resolve net prefix 
                allowed_net=$(circuit_resolve_address "$allowed_net" ipv4)
                log_info "translated PREFIX $allowed_net..."
            esac
            
            log_info "siproxd allowed_net $allowed_net..."

            # concatenate allowed nets
            siproxd_allowed_nets=$(join_by ',' ${siproxd_allowed_nets} $allowed_net)
            log_info "siproxd allowed_nets $siproxd_allowed_nets..."
            
            # set up redirect firewall rule if siproxd is configured as transparent proxy
            if [ $siproxd_transparent = 'yes' -a $allowed_net != '' ]; then
                log_info "configuring SIP transparent proxy via REDIRECT..."

                local siproxd_fw_rule="prot:udp $allowed_net 5060 REDIRECT:$siproxd_listen_port"
                local siproxd_fw_comment="transparent SIP proxy for net $allowed_net"
                fw_append_rule nat PORTFW "$siproxd_fw_rule" "$siproxd_fw_comment" exec_prerouting_rule
                log_info "SIP transparent proxy for net $allowed_net: '$siproxd_fw_rule'"
            fi
        done
        
        log_info "siproxd $siproxd_config_idx allowed_nets $siproxd_allowed_nets..."
        
        eval local siproxd_config_file=$SIPROX_CFG_DIR'/siproxd_'$siproxd_config_idx'.conf'
        eval local siproxd_registration_file='/var/lib/siproxd_registrations-'$siproxd_config_idx
        eval local siproxd_pid_file='/var/run/siproxd-'$siproxd_config_idx'.pid'

        log_info "writing siproxd config file $siproxd_config_file..."
        # write siproxd-x.conf
        {
        echo "# $siproxd_config_file for OPT_SIPROXD"
        echo '#'
        echo 'if_inbound  = '${siproxd_dev_in}
        echo 'if_outbound = '${siproxd_dev_out}
        echo 'hosts_allow_reg = '${siproxd_allowed_nets}
        echo 'sip_listen_port = '${siproxd_listen_port}
        echo 'daemonize = 1'
        echo '# silence_log = 1'
        echo 'user = nobody'
        echo 'registration_file = '${siproxd_registration_file}
        echo 'pid_file = '${siproxd_pid_file}
        echo 'rtp_proxy_enable = 1'
        echo 'rtp_port_low  = '${siproxd_rtp_port_min}
        echo 'rtp_port_high = '${siproxd_rtp_port_max}
        echo '# rtp_timeout = 300'
        echo '# default_expires = 600'
        echo '# debug_level = 0x00000015'
        echo '# plugin_dir: MUST be terminated with /'
        echo 'plugindir=/usr/lib/siproxd/'
        echo '#load_plugin=plugin_logcall.so'

        } > $siproxd_config_file;


        # parse users and store to siproxd passwd file
        eval local users_n='$SIPROXD_'$siproxd_config_idx'_USER_N'
        if [ $users_n -gt 0 ]; then
            eval local siproxd_password_file=$SIPROX_CFG_DIR'/siproxd_'$siproxd_config_idx'_passwd.conf'
            {
            echo '######################################################################'
            echo '#'
            echo '# Per user password file for siproxd'
            echo '#'
            echo '# format is:'
            echo '# <username> <password>'
            echo '# username and password must not contains white spaces'
            echo '#'
            echo '######################################################################'
            echo ''
            echo ${current_user} ${current_password}
            } > $siproxd_password_file;

            for user_idx in $(seq 1 $users_n)
            do
                eval local current_user='$SIPROXD_'$siproxd_config_idx'_USER_'$user_idx'_NAME'
                eval local current_password='$SIPROXD_'$siproxd_config_idx'_USER_'$user_idx'_PASS'

                echo ${current_user} ${current_password} >> $siproxd_password_file;
            done
            
            {
            echo 'proxy_auth_realm = siproxd@fli4l'
            echo 'proxy_auth_pwfile = '${siproxd_password_file}
            } >> $siproxd_config_file;
        fi

        # start siproxd
        /usr/sbin/siproxd --config $siproxd_config_file
        log_info "siproxd started: /usr/sbin/siproxd --config $siproxd_config_file"

    done

    end_script
esac