functions

#!/bin/bash
####################################################################
# Prey Core Basic Functions - by Tomas Pollak (bootlog.org)
# URL: http://preyproject.com
# License: GPLv3
####################################################################

log(){
	eval echo -e '"$1"' "$log_output"
}

####################################################################
# xml parsing functions
####################################################################

get_key(){
	echo "$1" | sed -e 's/.*\/\(.*\)>/\1/' -e 'y/-/_/' # we also replace -'s to _'s
}

get_value(){
	echo "$1" | sed 's/.*>\([^<].*\)<.*/\1/'
}

# expects attr name, returns value
# example: get_attribute 'name' $line
get_attribute(){
	echo "$2" | sed "s/.*$1=\"\([^\"]*\)\".*/\1/"
	# echo "$2" | sed -e "s/.*$1=\([a-z_\"']*\).*/\1/" -e "s/[^a-z_]//g"
}

####################################################################
# setting configs
####################################################################

# key, value
set_config(){
	if [ -n "$1" ] && [ -n "$2" ]; then
		local clean_key=$(echo "$1" | sed "s/^[0-9]/_/;s/[^a-zA-Z0-9_]/_/g")
		local clean_val=$(printf "%q" "$2")
		eval "${clean_key}=${clean_val}"
	fi
}

# module, key, value
set_module_config(){
	set_config "${1}__${2}" "$3"
}

save_config_value(){
	local key="$1"
	local val="$2"

	if [ "$val" == "true" ]; then
		local val='y'
	elif [ "$val" == 'false' ]; then
		local val='n'
	fi

	# use % as delimiter instead of / so URLs get set correctly
	sed -i.backup -e "s%^$key=.*%$key='$val'%" "$config_file" 2> /dev/null
	local rs=$?
	if [ -f "$config_file" ]; then
		rm -f "$config_file.backup" 2> /dev/null
	else
		mv "$config_file.backup" "$config_file" 2> /dev/null
	fi

	return $rs
}

####################################################################
# local var storage
####################################################################

# fetches a var and then assigns it as $value
# expects the name of hash and then the name of var
get_var(){
	HASH="$1[*]"
	local ${!HASH}
	eval 'echo ${'"${2}"'}'
}

store_var(){
	eval $1[\${#$1[*]}]="$2"
}

store_key_value(){
	store_var "$1" "$2=\"$3\""
}

# if you need to fetch a specific trace or file
get_trace(){
	get_var traces ${1}__$2
}

get_file(){
	get_var files ${1}__$2
}

####################################################################
# list generators for report
####################################################################

separator='########################################################'

generate_query_string(){

	local default_prefix="\n -F "
	[ -n "$2" ] && prefix="$2" || prefix="$default_prefix"

	for t in $(eval echo \${$1[@]}); do

		local start=$(echo ${t%%=*})
		local index=$(echo $(( ${#start} + 1 )))

		if [ "$prefix" != "$default_prefix" ]; then
			local trace_field=`echo "$start" | sed "s/^\([^_].*\)__\(.*\)/[\1][\2]/"`
		else
			local trace_field=`echo "$start" | sed 's/^\([^_].*\)__\(.*\)/\1[\2]/'`
		fi

		echo -n "${prefix}${trace_field}=${t:index}"

	done

}

generate_list(){
	for t in $(eval echo \${$1[@]}); do
		local current_node=$(echo $t | sed 's/__.*//')
		[ "$current_node" != "$previous_node" ] && echo -e "$separator\n# $current_node\n$separator\n"
		# removes module name and replaces _'s with whitespaces
		echo -e "$t\n" | sed -e 's/^\([^_].*\)__/ :: /' -e 's/%20/ /g' -e 's/_/ /'
		local previous_node=$current_node
	done
}

####################################################################
# trace & file functions
####################################################################

add_trace(){
	log " ++ Adding trace for $current_module: $1"
	store_key_value 'traces' "${current_module}__$1" "$(urlencode "$2")"
}

remove_traces(){
	unset -v traces
	log " -- Dropping all traces!"
}

add_file(){
	if [ -f "$2" ]; then
		log " ++ Adding file for $current_module: $1 -> $2"
		store_key_value 'files' "${current_module}__$1" "$2"
	else
		log " ${red}!!${color_end} Couldn't find file at $2!"
	fi
}

list_files(){
	# log " -- ${#files[*]} files gathered!"
	for f in "${files[@]}"; do
		if [ "$post_method" == 'http' ]; then
			# echo -e "-F $f" | sed -e 's/=/=@/'
			echo "-F $f" | sed 's/^\([^_].*\)__\([^=].*\)=\(.*\)/\1[\2]=@\3/'
		else # just list the file paths
			echo $f | sed 's/^.*=\(.*\)/\1/'
		fi
	done
}

remove_files(){
	for f in "${files[@]}"; do
		file=`echo $f | sed 's/^.*=\(.*\)/\1/'`
		rm -f "$file"
		log " -- Removed $file"
	done
	unset -v files
}

####################################################################
# delay functions, mac and linux
####################################################################

# echoes random number between 1 and $1 (first argument passed)
get_random_number(){
	echo $[ ( $RANDOM % $1 ) + 1 ]
}

# returns 1 if cron entry is set to one our intervals
one_hour_interval(){
	echo "$current_delay" | grep "/" > /dev/null || echo 1
}

# returns cron delay depending on device's state:
# when missing, every X minutes, otherwise every hour on minute X
get_delay_for(){
	echo '*/'$1' * * * *'
}

get_random_minute_delay(){
	local min=$(get_random_number 59)
	echo "${min} * * * *"
}

get_current_delay(){
	# crontab -l | grep prey | sed "s/^..\([0-9]*\).*/\1/"
	crontab -l 2> /dev/null | grep prey | head -1 | sed 's/ \/.*//'
}

update_execution_delay(){
	local full_path=$(full_path "$base_path")
	(crontab -l 2> /dev/null | grep -v prey; echo "${1}" "${full_path}/prey.sh > /var/log/prey.log 2>&1") | crontab -
}

# if device is missing we'll make sure the current delay matches the one
# on the server. otherwise we'll make sure it is set to the regular interval.
check_and_update_delay(){
	local current_delay=$(get_current_delay)

	# if trigger is loaded and device not missing, set to one hour intervals
	if [[ -n "$current_delay" && -n "$(is_trigger_loaded)" && -z "$device_missing" ]]; then

		# if already set to one hour interval, return
		[ -n "$(one_hour_interval)" ] && return 0

		local new_delay=$(get_random_minute_delay)
		log " -- Setting delay to regular interval."

	else

		local new_delay=$(get_delay_for "$1")

		# if interval hasn't changed, return
		[ "$current_delay" == "$new_delay" ] && return 0
		log " -- Setting frequency to $1!"

	fi

	update_execution_delay "$new_delay"

}

#ensure_trigger_loaded(){
#	[ -z "$(is_trigger_loaded)" ] && reload_trigger
#}

running_from_cron(){
	# tty -s
	# [ $? -eq 1 ] && echo 1
	[ "$TERM" == "dumb" ] && echo 1
}

####################################################################
# http functions
####################################################################

# if try_proxy does not contain a dot (e.g. 'true' or something else)
# then lets make sure we use a valid proxy.
get_proxy_server(){
	[ -n "$try_proxy" ] && echo "$try_proxy" || get_system_proxy
}

send_request(){

	local url="$1"
	local curl_arguments="$2"
	local proxy_to_use="$3"
	local headers_file="$tmpbase/prey-curl-headers.txt"

	if [ -n "$proxy_to_use" ]; then
		log " -- Trying via proxy: ${proxy_to_use}..."
		curl_arguments="$curl_arguments -x $proxy_to_use"
	fi

	response_body=$(getter $curl_arguments -L $url --dump-header "$headers_file" -S --stderr -)
	local rs=$?

	if [[ $rs -eq 0 && -f "$headers_file" ]]; then

		response_headers=$(cat "$headers_file" && rm -f "$headers_file" 2> /dev/null)
		get_status_code

	elif [ -z "$proxy_to_use" ]; then

		if [ -z "$proxy_checked" ]; then
			proxy_server=$(get_proxy_server)
			proxy_checked=1
		fi

		if [ -n "$proxy_server" ]; then
			send_request "$url" "$curl_arguments" "$proxy_server"
		else
			log_response_error "$url"
		fi

	else # tried proxy to no avail.

		# it may be possible that the proxy does not support SSL,
		# so we can try switching to plain HTTP as a last resort
		if [ -n "$(find_in "$url" 'https:')" ]; then
			local new_url=$(echo "$url" | sed 's/https:/http:/')
			send_request "$new_url" "$curl_arguments" "$proxy_to_use"
		else
			log_response_error "$url" "$proxy_to_use"
		fi

	fi

}

get_status_code(){
	# if we get a redirect response, we should capture the last http status code
	response_status=$(echo -e "$response_headers" | grep 'HTTP/' | tail -1 | cut -d" " -f2)
}

# we may eventually use a specific header for Prey
get_header_value(){
	echo "$response_headers" | grep -i "$1" | tail -1 | sed 's/.*: \([a-z\/-]*\).*/\1/'
}

# fetches last response if online actions were enabled for the device
get_last_response(){
	response_body=$(cat "$last_response")
}

log_response_error(){
	local url="$1"
	local proxy_used="$2"
	log "\n !! Got invalid response! This probably means there is a connection issue."
	log " -- Please check your firewall settings, allowing Curl to connect to ${url} through port 80."
	log " -- If you use a proxy server please check the try_proxy setting in the config file."
	[ -n "$proxy_used" ] && log " -- Proxy server found: ${proxy_used}"
	log " -- The response we got was: \n\n${response_headers}\n${response_body}\n"
}

####################################################################
# check mode functions
####################################################################

verify_installation(){
	log " -- Checking if cron daemon is running..."
	if [ -n $(is_process_running 'cron') ]; then
		log " -- Cron daemon found."
	else
		log " !! Cron daemon not found! Try running it with 'sudo /etc/init.d/cron start'."
	fi
	log " -- Checking for crontab entry..."
	local result=$(crontab -l | grep 'prey.sh' | wc -l 2> /dev/null)
	if [ "$result" -gt 0 ]; then
		log " -- Found!"
	else
		log " !! Not found!\n -> It seems Prey's crontab entry was removed after installation. Please set again the running interval."
	fi
}

verify_smtp_settings(){

	if [ "$mail_to" != "mailbox@domain.com" ]; then
		log " -- Target mailbox set."
	else
		log " !! Target mailbox not set!"
	fi

	if [ "$smtp_username" != "username@gmail.com" ]; then
		log " -- SMTP username set."
	else
		log " !! SMTP username not set!"
	fi

	if [ "$(decrypt $smtp_password)" != "" ]; then
		log " -- Password seems to be fine as well."
	else
		log " !! Password not set! (Remember it should be base64 encrypted)."
	fi

}

####################################################################
# self setup functions
####################################################################

get_hardware_info(){
	initialize_module "system"
	scan_system_hardware
	full_hardware_params
}

self_setup(){

	log ' -- Gathering system and hardware information...'
	get_pc_info
	local pc_hardware_params="$(get_hardware_info)"

	log ' -- Sending request to Control Panel...'

	[ "$os" == "linux" ] && local os_name=$distro_name || local os_name=$os
	local params="device[title]=$(urlencode "$pc_name")&device[device_type]=$pc_type&device[os_version]=$pc_os_version&device[os]=$(capitalize $os_name)${pc_hardware_params}"

	send_request "$control_panel_url/devices.xml" "--connect-timeout 20 -u $api_key:x -d "$params""
	log " -- Got response status ${response_status}."

	device_key=$(echo "$response_body" | grep "<key>" | sed 's/.*<key>\(.*\)<\/key>.*/\1/')

	if [ -n "$device_key" ]; then

		log ' -- Device succesfully registered! Applying configuration...'
		save_config_value device_key "$device_key"

		if [ $? == 1 ]; then
			log " -- There was a problem saving the configuration. You probably don't have permissions to modify $base_path/config."
		else
			log " -- All set. Assigned key is $device_key."
		fi

	else

		log " -- Couldn't add this device to your account. Make sure you have available slots!\n"
		exit 1

	fi

}