#!/bin/bash
# Copyright (c) 2004-2005 Gentoo Foundation
# Distributed under the terms of the GNU General Public License v2
# $Header:  $

# function rename wrapper - remove for baselayout-1.12.x
if [[ $( type -t bash_variable ) != "function" ]] ; then
    bash_variable() {
	interface_variable "$*"
    }
fi

# char* pppd_provides(void)
#
# Returns a string to change module definition for starting up
pppd_provides() {
    echo "ppp"
}

# void pppd_depend(void)
#
# Sets up the dependancies for the module
pppd_depend() {
    after interface
    before dhcp
}

# bool pppd_check_installed(void)
#
# Returns 1 if pppd is installed, otherwise 0
pppd_check_installed() {
    if [[ ! -x /usr/sbin/pppd ]]; then
	${1:-false} && eerror "For PPP support, emerge net-dialup/ppp"
	return 1
    fi
    return 0
}

# bool pppd_check_depends(void)
#
# Checks to see if we have the needed functions
pppd_check_depends() {
    return 0
}

# bool pppd_update_secrets_file(char* filepath, char* username, \
#	char* remotename, char* password)
#
# Add/update PAP/CHAP authentication information 
pppd_update_secrets_file() {
    local file="$1" user="$2" remote="$3" password="$4"
    local tmpfile="/tmp/ppp-secret.$$"

    touch "${tmpfile}" || return 1
    chmod 0600 "${tmpfile}" || return 1

    if [[ -e "${file}" ]]; then
	# Build a egrep to find all possible entries in the secrets file
	do_quote() {
	    echo "^[ \t]*$1$2$1[ \t]*$3$4$3[ \t]"
	}
	local e="$( do_quote "" "${user}" "" "${remote}" )"
	e="${e}|$( do_quote '"' "${user}" "" "${remote}" )"
	e="${e}|$( do_quote '"' "${user}" '"' "${remote}" )"
	e="${e}|$( do_quote "" "${user}" '"' "${remote}" )"
	e="${e}|$( do_quote "'" "${user}" "" "${remote}" )"
	e="${e}|$( do_quote "'" "${user}" "'" "${remote}" )"
	e="${e}|$( do_quote "" "${user}" "'" "${remote}" )"
	unset -f do_quote

	egrep -v "${e}" "${file}" > "${tmpfile}"
    fi
    echo "\"${user}\"\t\"${remote}\"\t\"${password}\"" >> "${tmpfile}"

    [[ -e ${file} ]] && vewarn "Authentication info has been added to ${file}"
    mv "${tmpfile}" "${file}" ||  return 1
    
    return 0
}

# bool pppd_start(char *iface)
#
# Start PPP on an interface by calling pppd
#
# Returns 0 (true) when successful, otherwise 1
pppd_start() {
    local iface="$1" ifvar=$( bash_variable "$1" ) opts="" link
    if [[ ${iface%%[0-9]*} != "ppp" ]]; then
	eerror "PPP can only be invoked from net.ppp[0-9]"
	return 1
    fi

    local unit="${iface#ppp}"
    if [[ -z ${unit} ]] ; then
	eerror "PPP requires a unit - use net.ppp[0-9] instead of net.ppp"
	return 1
    fi

    # PPP requires a link to communictate over - normally a serial port
    # PPPoE communicates over ethernet
    # PPPoA communictes over ATM
    # In all cases, the link needs to be available before we start PPP
    eval link=\"\$\{link_${ifvar}\}\"
    if [[ -z ${link} ]]; then
	eerror "link_${ifvar} has not been set in /etc/conf.d/net"
	return 1
    fi

    # Might or might not be set in conf.d/net
    local user password i
    eval username=\"\$\{username_${ifvar}\}\"
    eval password=\"\$\{password_${ifvar}\}\"

    #Add/update info in PAP/CHAP secrets files
    if [[ -n ${username} && -n ${password} ]]; then
	if ! pppd_update_secrets_file "/etc/ppp/pap-secrets" \
	    "${username}" "${link}" "${password}" ; then
	    eerror "Failed to update ${file}"
	    return 1
	fi
	if ! pppd_update_secrets_file "/etc/ppp/chap-secrets" \
	    "${username}" "${link}" "${password}" ; then
	    eerror "Failed to update ${file}"
	    return 1
	fi
    fi

    local -a plugins
    eval plugins=( \"\$\{plugins_${ifvar}\}\" )
    for (( i=0; i<${#plugins[@]}; i++ )); do
	local -a plugin=( ${plugins[i]} )
	# Bound to be some users who do this
	[[ ${plugin[0]} == "pppoe" ]] && plugin[0]="rp-pppoe"
	[[ ${plugin[0]} == "pppoa" ]] && plugin[0]="pppoatm"
	
	[[ ${plugin[0]} == "rp-pppoe" ]] && opts="${opts} connect true"
	opts="${opts} plugin ${plugin[0]}.so ${plugin[@]:1}"
    done

    if [[ " ${opts} " == *" plugin rp-pppoe.so "* ]]; then
	# Ensure that the link exists and is up
	interface_exists "${link}" true || return 1
	interface_up "${link}"
	
	# Load the pppoe kernel module - if this fails, we have to hope
	# that pppoe support is compiled into the kernel
	modprobe pppoe 2>/dev/null

	# Default pppoe options - the user can override these using
	# pppd_ppp0="..."
	opts="${opts} noaccomp noccp nobsdcomp nodeflate \
	nopcomp novj novjccomp"
    fi
    
    # Load any commandline options
    eval opts=\"\$\{opts\} \$\{pppd_${ifvar}\} unit ${unit} \"

    # Check for mtu/mru
    local mtu
    eval mtu=\"\$\{mtu_${ifvar}:-1492\}\"
    [[ " ${opts} " != *" mtu "* ]] && opts="${opts} mtu ${mtu}"
    [[ " ${opts} " != *" mru "* ]] && opts="${opts} mru ${mtu}"

    # Don't detach if we're not idling
    [[ " ${opts} " != *" idle "* && " ${opts} " != *" nodetach "* \
    && " ${opts} " != *" updetach "* ]] \
    && opts="${opts} nodetach"

    [[ -n ${username} ]] && opts="${opts} user ${username}"
   
    ebegin "Running pppd"
    i=$( /usr/sbin/pppd persist maxfail 0 ${opts} \
    remotename "${link}" linkname "${iface}" ipparam "${link}" )
    eend $? "${i}" || return 1
}

# bool pppd_stop(char *iface)
#
# Stop PPP link by killing the associated pppd process
#
# Returns 0 (true) if no process to kill or it terminates successfully,
# otherwise non-zero (false)
pppd_stop() {
    local iface="$1" pidfile="/var/run/ppp-$1.pid"

    [[ ! -s ${pidfile} ]] && return 0 

    local pid=$( head -n 1 "${pidfile}" )
    einfo "Stopping pppd on ${iface}"
    kill -s TERM "${pid}"
    process_finished "${pid}" /usr/sbin/pppd
    eend $?
}