mirror of
https://passt.top/passt
synced 2024-06-30 06:52:40 +00:00
94c7c1dbcf
Based on an original patch by Giuseppe Scrivano: there's no need to pass $0 to usage, drop that everywhere, and make it consistent. Don't exit with error on -h, --help. Suggested-by: Giuseppe Scrivano <gscrivan@redhat.com> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
229 lines
6.1 KiB
Bash
Executable File
229 lines
6.1 KiB
Bash
Executable File
#!/bin/sh -euf
|
|
#
|
|
# SPDX-License-Identifier: AGPL-3.0-or-later
|
|
#
|
|
# PASST - Plug A Simple Socket Transport
|
|
# for qemu/UNIX domain socket mode
|
|
#
|
|
# PASTA - Pack A Subtle Tap Abstraction
|
|
# for network namespace/tap device mode
|
|
#
|
|
# slirp4netns.sh - Compatibility wrapper for pasta, behaving like slirp4netns(1)
|
|
#
|
|
# WARNING: Draft quality, not really tested, --enable-sandbox not supported yet
|
|
#
|
|
# Copyright (c) 2021 Red Hat GmbH
|
|
# Author: Stefano Brivio <sbrivio@redhat.com>
|
|
|
|
PASTA_PID="$(mktemp)"
|
|
PASTA_OPTS="-q --ipv4-only -a 10.0.2.0 -n 24 -g 10.0.2.2 -m 1500 --no-ndp --no-dhcpv6 --no-dhcp -P ${PASTA_PID}"
|
|
USAGE_RET=1
|
|
|
|
# add() - Add single option to $PASTA_OPTS
|
|
# $1: Option name, with or without argument
|
|
add() {
|
|
PASTA_OPTS="${PASTA_OPTS} ${1}"
|
|
}
|
|
|
|
# drop() - Drop one option (without argument) from $PASTA_OPTS
|
|
# $1: Option name
|
|
drop() {
|
|
old_opts="${PASTA_OPTS}"; PASTA_OPTS=
|
|
for o in ${old_opts}; do [ "${o}" != "${1}" ] && add "${o}"; done
|
|
}
|
|
|
|
# sub() - Substitute option in $PASTA_OPTS, with or without argument
|
|
# $1: Option name
|
|
# $2: Option argument, can be empty
|
|
sub() {
|
|
old_opts="${PASTA_OPTS}"; PASTA_OPTS=
|
|
next=0
|
|
for o in ${old_opts}; do
|
|
if [ ${next} -eq 1 ]; then
|
|
next=0; add "${1} ${2}"; shift; shift; continue
|
|
fi
|
|
|
|
for r in ${@}; do [ "${o}" = "${r}" ] && next=1 && break; done
|
|
[ "${next}" -eq 0 ] && add "${o}"
|
|
done
|
|
}
|
|
|
|
# xorshift() - pseudorandom permutation of 16-bit group
|
|
# $1: 16-bit value to shuffle
|
|
xorshift() {
|
|
# Adaptation of Xorshift algorithm from:
|
|
# Marsaglia, G. (2003). Xorshift RNGs.
|
|
# Journal of Statistical Software, 8(14), 1 - 6.
|
|
# doi:http://dx.doi.org/10.18637/jss.v008.i14
|
|
# with triplet (5, 3, 1), suitable for 16-bit ranges.
|
|
n=${1}
|
|
: $((n ^= n << 5))
|
|
: $((n ^= n >> 3))
|
|
: $((n ^= n << 1))
|
|
echo ${n}
|
|
}
|
|
|
|
# opt() - Validate single option from getopts
|
|
# $1: Option type
|
|
# $@: Variable names to assign to
|
|
opt() {
|
|
case "${1}" in
|
|
u32)
|
|
if ! printf "%i" "${OPTARG}" >/dev/null 2>&1 || \
|
|
[ "${OPTARG}" -lt 0 ]; then
|
|
echo "${OPT} must be a non-negative integer"
|
|
usage
|
|
fi
|
|
eval ${2}="${OPTARG}"
|
|
;;
|
|
mtu)
|
|
if ! printf "%i" "${OPTARG}" >/dev/null 2>&1 || \
|
|
[ "${OPTARG}" -lt 0 ] || [ "${OPTARG}" -ge 65522 ]; then
|
|
echo "MTU must be a positive integer (< 65522)"
|
|
usage
|
|
fi
|
|
eval ${2}="${OPTARG}"
|
|
;;
|
|
str)
|
|
eval ${2}="${OPTARG}"
|
|
;;
|
|
net4)
|
|
addr="${OPTARG%/*}"
|
|
mask="${OPTARG##*/}"
|
|
|
|
{ [ -z "${mask}" ] || !printf "%i" "${mask}" >/dev/null 2>&1 \
|
|
|| [ ${mask} -gt 32 ] || ${mask} -le 0 ]; } && usage
|
|
|
|
expr "${addr}" : \
|
|
'[0-9][0-9]*\.[0-9][0-9]*\.[0-9][0-9]*\.[0-9][0-9]*$' \
|
|
>/dev/null
|
|
[ $? -ne 0 ] && usage
|
|
|
|
ifs="${IFS}"; IFS='.'
|
|
for q in ${addr}; do [ ${q} -gt 255 ] && usage; done
|
|
IFS="${ifs}"
|
|
|
|
eval ${2}="${addr}"
|
|
eval ${3}="${mask}"
|
|
;;
|
|
esac
|
|
}
|
|
|
|
# usage() - Print slirpnetns(1) usage and exit indicating failure
|
|
# $1: Invalid option name, if any
|
|
usage() {
|
|
[ ${#} -eq 1 ] && printf "%s: invalid option -- '%s'\n" "${0}" "${1}"
|
|
cat << EOF
|
|
Usage: ${0} [OPTION]... PID|PATH TAPNAME
|
|
User-mode networking for unprivileged network namespaces.
|
|
|
|
-c, --configure bring up the interface
|
|
-e, --exit-fd=FD specify the FD for terminating slirp4netns
|
|
-r, --ready-fd=FD specify the FD to write to when the network is configured
|
|
-m, --mtu=MTU specify MTU (default=1500, max=65521)
|
|
-6, --enable-ipv6 enable IPv6 (experimental)
|
|
-a, --api-socket=PATH specify API socket path
|
|
--cidr=CIDR specify network address CIDR (default=10.0.2.0/24)
|
|
--disable-host-loopback prohibit connecting to 127.0.0.1:* on the host namespace
|
|
--netns-type=TYPE specify network namespace type ([path|pid], default=pid)
|
|
--userns-path=PATH specify user namespace path
|
|
--enable-sandbox create a new mount namespace (and drop all caps except CAP_NET_BIND_SERVICE if running as the root)
|
|
--enable-seccomp enable seccomp to limit syscalls (experimental)
|
|
-h, --help show this help and exit
|
|
-v, --version show version and exit
|
|
EOF
|
|
exit ${USAGE_RET}
|
|
}
|
|
|
|
# version() - Print version
|
|
version() {
|
|
echo "slirp4netns-like wrapper for pasta"
|
|
exit 0
|
|
}
|
|
|
|
# gen_addr6() - Generate pseudorandom IPv6 address, changes every second
|
|
gen_addr6() {
|
|
printf "fd00"
|
|
n=$(($(xorshift $(date +%S)) % 65536))
|
|
for i in $(seq 2 8); do
|
|
printf ":%04x" ${n}
|
|
n=$(($(xorshift ${n}) % 65536))
|
|
done
|
|
}
|
|
|
|
# Default options
|
|
v6=0
|
|
get_pid=0
|
|
MTU=1500
|
|
A4="10.0.2.0"
|
|
M4="255.255.255.0"
|
|
no_map_gw=0
|
|
EFD=0
|
|
RFD=0
|
|
|
|
while getopts ce:r:m:6a:hv-: OPT 2>/dev/null; do
|
|
if [ "${OPT}" = "-" ]; then
|
|
OPT="${OPTARG%%[= ]*}"
|
|
OPTARG="${OPTARG#${OPT}[= ]}"
|
|
fi
|
|
case "${OPT}" in
|
|
c | configure) add "--config-net" ;;
|
|
e | exit-fd) opt u32 EFD ;;
|
|
r | ready-fd) opt u32 RFD ;;
|
|
m | mtu) opt mtu MTU && sub -m ${MTU} ;;
|
|
6 | enable-ipv6) V6=1 ;;
|
|
a | api-socket) opt str API ;;
|
|
cidr) opt net4 A4 M4 && sub -a ${A4} -n ${M4} ;;
|
|
disable-host-loopback) add "--no-map-gw" && no_map_gw=1 ;;
|
|
netns-type) : Autodetected ;;
|
|
userns-path) opt_str USERNS_NAME "${OPTARG}" ;;
|
|
enable-sandbox) : Not supported yet ;;
|
|
enable-seccomp) : Cannot be disabled ;;
|
|
h | help) USAGE_RET=0 && usage ;;
|
|
v | version) version ;;
|
|
??*) usage "${OPT}" ;;
|
|
?) usage "${OPT}" ;;
|
|
esac
|
|
done
|
|
|
|
shift $((OPTIND - 1))
|
|
[ ${#} -ne 2 ] && usage
|
|
ns_spec="${1}"
|
|
|
|
ifname="${2}"
|
|
add "-I ${ifname}"
|
|
|
|
if [ ${v6} -eq 1 ]; then
|
|
drop "--ipv4-only"
|
|
add "-a $(gen_addr6) -g fd00::2 -D fd00::3"
|
|
fi
|
|
|
|
./pasta ${PASTA_OPTS} ${ns_spec} 2>/dev/null && \
|
|
[ ${RFD} -ne 0 ] && echo "1" >&${RFD}
|
|
|
|
trap "kill $(cat ${PASTA_PID}); rm ${PASTA_PID}" INT TERM
|
|
|
|
cat << EOF
|
|
sent tapfd=5 for ${ifname}
|
|
received tapfd=5
|
|
Starting slirp
|
|
* MTU: ${MTU}
|
|
* Network: ${A4}
|
|
* Netmask: ${M4}
|
|
* Gateway: 10.0.2.2
|
|
* DNS: 10.0.2.3
|
|
* Recommended IP: 10.0.2.100
|
|
EOF
|
|
|
|
if [ ${no_map_gw} -eq 0 ]; then
|
|
echo "WARNING: 127.0.0.1:* on the host is accessible as 10.0.2.2 (set --disable-host-loopback to prohibit connecting to 127.0.0.1:*)"
|
|
fi
|
|
|
|
if [ ${EFD} -ne 0 ]; then
|
|
dd count=1 of=/dev/null 2>/dev/null <&${EFD}
|
|
else
|
|
while read a; do :; done
|
|
fi
|
|
|
|
exit 0
|