mirror of
https://github.com/netdata/netdata.git
synced 2025-04-24 13:14:11 +00:00
295 lines
8 KiB
Bash
Executable file
295 lines
8 KiB
Bash
Executable file
#!/usr/bin/env bash
|
|
# shellcheck disable=SC1117
|
|
|
|
# cgroup-network-helper.sh
|
|
# detect container and virtual machine interfaces
|
|
#
|
|
# (C) 2017 Costa Tsaousis
|
|
# SPDX-License-Identifier: GPL-3.0-or-later
|
|
#
|
|
# This script is called as root (by cgroup-network), with either a pid, or a cgroup path.
|
|
# It tries to find all the network interfaces that belong to the same cgroup.
|
|
#
|
|
# It supports several method for this detection:
|
|
#
|
|
# 1. cgroup-network (the binary father of this script) detects veth network interfaces,
|
|
# by examining iflink and ifindex IDs and switching namespaces
|
|
# (it also detects the interface name as it is used by the container).
|
|
#
|
|
# 2. this script, uses /proc/PID/fdinfo to find tun/tap network interfaces.
|
|
#
|
|
# 3. this script, calls virsh to find libvirt network interfaces.
|
|
#
|
|
|
|
# -----------------------------------------------------------------------------
|
|
|
|
# the system path is cleared by cgroup-network
|
|
# shellcheck source=/dev/null
|
|
[ -f /etc/profile ] && source /etc/profile
|
|
|
|
export LC_ALL=C
|
|
|
|
PROGRAM_NAME="$(basename "${0}")"
|
|
|
|
logdate() {
|
|
date "+%Y-%m-%d %H:%M:%S"
|
|
}
|
|
|
|
log() {
|
|
local status="${1}"
|
|
shift
|
|
|
|
echo >&2 "$(logdate): ${PROGRAM_NAME}: ${status}: ${*}"
|
|
|
|
}
|
|
|
|
warning() {
|
|
log WARNING "${@}"
|
|
}
|
|
|
|
error() {
|
|
log ERROR "${@}"
|
|
}
|
|
|
|
info() {
|
|
log INFO "${@}"
|
|
}
|
|
|
|
fatal() {
|
|
log FATAL "${@}"
|
|
exit 1
|
|
}
|
|
|
|
debug=${NETDATA_CGROUP_NETWORK_HELPER_DEBUG=0}
|
|
debug() {
|
|
[ "${debug}" = "1" ] && log DEBUG "${@}"
|
|
}
|
|
|
|
# -----------------------------------------------------------------------------
|
|
# check for BASH v4+ (required for associative arrays)
|
|
|
|
[ $(( BASH_VERSINFO[0] )) -lt 4 ] && \
|
|
fatal "BASH version 4 or later is required (this is ${BASH_VERSION})."
|
|
|
|
# -----------------------------------------------------------------------------
|
|
# parse the arguments
|
|
|
|
pid=
|
|
cgroup=
|
|
while [ ! -z "${1}" ]
|
|
do
|
|
case "${1}" in
|
|
--cgroup) cgroup="${2}"; shift 1;;
|
|
--pid|-p) pid="${2}"; shift 1;;
|
|
--debug|debug) debug=1;;
|
|
*) fatal "Cannot understand argument '${1}'";;
|
|
esac
|
|
|
|
shift
|
|
done
|
|
|
|
if [ -z "${pid}" ] && [ -z "${cgroup}" ]
|
|
then
|
|
fatal "Either --pid or --cgroup is required"
|
|
fi
|
|
|
|
# -----------------------------------------------------------------------------
|
|
|
|
set_source() {
|
|
[ ${debug} -eq 1 ] && echo "SRC ${*}"
|
|
}
|
|
|
|
|
|
# -----------------------------------------------------------------------------
|
|
# veth interfaces via cgroup
|
|
|
|
# cgroup-network can detect veth interfaces by itself (written in C).
|
|
# If you seek for a shell version of what it does, check this:
|
|
# https://github.com/netdata/netdata/issues/474#issuecomment-317866709
|
|
|
|
|
|
# -----------------------------------------------------------------------------
|
|
# tun/tap interfaces via /proc/PID/fdinfo
|
|
|
|
# find any tun/tap devices linked to a pid
|
|
proc_pid_fdinfo_iff() {
|
|
local p="${1}" # the pid
|
|
|
|
debug "Searching for tun/tap interfaces for pid ${p}..."
|
|
set_source "fdinfo"
|
|
grep "^iff:.*" "${NETDATA_HOST_PREFIX}/proc/${p}/fdinfo"/* 2>/dev/null | cut -f 2
|
|
}
|
|
|
|
find_tun_tap_interfaces_for_cgroup() {
|
|
local c="${1}" # the cgroup path
|
|
|
|
# for each pid of the cgroup
|
|
# find any tun/tap devices linked to the pid
|
|
if [ -f "${c}/emulator/cgroup.procs" ]
|
|
then
|
|
local p
|
|
for p in $(< "${c}/emulator/cgroup.procs" )
|
|
do
|
|
proc_pid_fdinfo_iff "${p}"
|
|
done
|
|
else
|
|
debug "Cannot find file '${c}/emulator/cgroup.procs', not searching for tun/tap interfaces."
|
|
fi
|
|
}
|
|
|
|
|
|
# -----------------------------------------------------------------------------
|
|
# virsh domain network interfaces
|
|
|
|
virsh_cgroup_to_domain_name() {
|
|
local c="${1}" # the cgroup path
|
|
|
|
debug "extracting a possible virsh domain from cgroup ${c}..."
|
|
|
|
# extract for the cgroup path
|
|
sed -n -e "s|.*/machine-qemu\\\\x2d[0-9]\+\\\\x2d\(.*\)\.scope$|\1|p" \
|
|
-e "s|.*/machine/\(.*\)\.libvirt-qemu$|\1|p" \
|
|
<<EOF
|
|
${c}
|
|
EOF
|
|
}
|
|
|
|
virsh_find_all_interfaces_for_cgroup() {
|
|
local c="${1}" # the cgroup path
|
|
|
|
# the virsh command
|
|
local virsh
|
|
# shellcheck disable=SC2230
|
|
virsh="$(which virsh 2>/dev/null || command -v virsh 2>/dev/null)"
|
|
|
|
if [ ! -z "${virsh}" ]
|
|
then
|
|
local d
|
|
d="$(virsh_cgroup_to_domain_name "${c}")"
|
|
|
|
if [ ! -z "${d}" ]
|
|
then
|
|
debug "running: virsh domiflist ${d}; to find the network interfaces"
|
|
|
|
# match only 'network' interfaces from virsh output
|
|
|
|
set_source "virsh"
|
|
"${virsh}" -r domiflist "${d}" |\
|
|
sed -n \
|
|
-e "s|^\([^[:space:]]\+\)[[:space:]]\+network[[:space:]]\+\([^[:space:]]\+\)[[:space:]]\+[^[:space:]]\+[[:space:]]\+[^[:space:]]\+$|\1 \1_\2|p" \
|
|
-e "s|^\([^[:space:]]\+\)[[:space:]]\+bridge[[:space:]]\+\([^[:space:]]\+\)[[:space:]]\+[^[:space:]]\+[[:space:]]\+[^[:space:]]\+$|\1 \1_\2|p"
|
|
else
|
|
debug "no virsh domain extracted from cgroup ${c}"
|
|
fi
|
|
else
|
|
debug "virsh command is not available"
|
|
fi
|
|
}
|
|
|
|
# -----------------------------------------------------------------------------
|
|
# netnsid detected interfaces
|
|
|
|
netnsid_find_all_interfaces_for_pid() {
|
|
local pid="${1}"
|
|
[ -z "${pid}" ] && return 1
|
|
|
|
local nsid=$(lsns -t net -p ${pid} -o NETNSID -nr)
|
|
[ -z "${nsid}" -o "${nsid}" = "unassigned" ] && return 1
|
|
|
|
set_source "netnsid"
|
|
ip link show |\
|
|
grep -B 1 -E " link-netnsid ${nsid}($| )" |\
|
|
sed -n -e "s|^[[:space:]]*[0-9]\+:[[:space:]]\+\([A-Za-z0-9_]\+\)\(@[A-Za-z0-9_]\+\)*:[[:space:]].*$|\1|p"
|
|
}
|
|
|
|
netnsid_find_all_interfaces_for_cgroup() {
|
|
local c="${1}" # the cgroup path
|
|
|
|
# for each pid of the cgroup
|
|
# find any tun/tap devices linked to the pid
|
|
if [ -f "${c}/cgroup.procs" ]
|
|
then
|
|
local p
|
|
for p in $(< "${c}/cgroup.procs" )
|
|
do
|
|
netnsid_find_all_interfaces_for_pid "${p}"
|
|
done
|
|
else
|
|
debug "Cannot find file '${c}/cgroup.procs', not searching for netnsid interfaces."
|
|
fi
|
|
}
|
|
|
|
# -----------------------------------------------------------------------------
|
|
|
|
find_all_interfaces_of_pid_or_cgroup() {
|
|
local p="${1}" c="${2}" # the pid and the cgroup path
|
|
|
|
if [ ! -z "${pid}" ]
|
|
then
|
|
# we have been called with a pid
|
|
|
|
proc_pid_fdinfo_iff "${p}"
|
|
netnsid_find_all_interfaces_for_pid "${p}"
|
|
|
|
elif [ ! -z "${c}" ]
|
|
then
|
|
# we have been called with a cgroup
|
|
|
|
info "searching for network interfaces of cgroup '${c}'"
|
|
|
|
find_tun_tap_interfaces_for_cgroup "${c}"
|
|
virsh_find_all_interfaces_for_cgroup "${c}"
|
|
netnsid_find_all_interfaces_for_cgroup "${c}"
|
|
|
|
else
|
|
|
|
error "Either a pid or a cgroup path is needed"
|
|
return 1
|
|
|
|
fi
|
|
|
|
return 0
|
|
}
|
|
|
|
# -----------------------------------------------------------------------------
|
|
|
|
# an associative array to store the interfaces
|
|
# the index is the interface name as seen by the host
|
|
# the value is the interface name as seen by the guest / container
|
|
declare -A devs=()
|
|
|
|
# store all interfaces found in the associative array
|
|
# this will also give the unique devices, as seen by the host
|
|
last_src=
|
|
# shellcheck disable=SC2162
|
|
while read host_device guest_device
|
|
do
|
|
[ -z "${host_device}" ] && continue
|
|
|
|
[ "${host_device}" = "SRC" ] && last_src="${guest_device}" && continue
|
|
|
|
# the default guest_device is the host_device
|
|
[ -z "${guest_device}" ] && guest_device="${host_device}"
|
|
|
|
# when we run in debug, show the source
|
|
debug "Found host device '${host_device}', guest device '${guest_device}', detected via '${last_src}'"
|
|
|
|
if [ -z "${devs[${host_device}]}" ] || [ "${devs[${host_device}]}" = "${host_device}" ]; then
|
|
devs[${host_device}]="${guest_device}"
|
|
fi
|
|
|
|
done < <( find_all_interfaces_of_pid_or_cgroup "${pid}" "${cgroup}" )
|
|
|
|
# print the interfaces found, in the format netdata expects them
|
|
found=0
|
|
for x in "${!devs[@]}"
|
|
do
|
|
found=$((found + 1))
|
|
echo "${x} ${devs[${x}]}"
|
|
done
|
|
|
|
debug "found ${found} network interfaces for pid '${pid}', cgroup '${cgroup}', run as ${USER}, ${UID}"
|
|
|
|
# let netdata know if we found any
|
|
[ ${found} -eq 0 ] && exit 1
|
|
exit 0
|