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merged 5 commits into from
Oct 11, 2025
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fix: Expose only selected ports with Passt #891

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486e525
fix: Expose only selected ports with Passt
kroese Oct 11, 2025
863d8ef
docs: Readme
kroese Oct 11, 2025
546b03e
Merge branch 'master' into dev
kroese Oct 11, 2025
4f9bc85
Update network.sh
kroese Oct 11, 2025
b1236dc
Update network.sh
kroese Oct 11, 2025
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9 changes: 8 additions & 1 deletion readme.md
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Original file line number Diff line number Diff line change
Expand Up @@ -242,7 +242,7 @@ kubectl apply -f https://raw.githubusercontent.com/qemus/qemu/refs/heads/master/

### How do I expose network ports?

You can expose ports just by adding them to your compose file. If you want to be able to connect to the SSH service of the machine for example, you would add it like this:
When using bridge networking, you can expose ports by adding them to your compose file. If you want to be able to connect to the SSH service of the machine for example, you would add it like this:

```yaml
ports:
Expand All @@ -251,6 +251,13 @@ kubectl apply -f https://raw.githubusercontent.com/qemus/qemu/refs/heads/master/

This will make port 2222 on your host redirect to port 22 of the virtual machine.

When using user-mode networking (for example when running under Podman), you will also need to add those ports to the `USER_PORTS` variable like this:

```yaml
environment:
USER_PORTS: "22,80,443"
```

### How do I assign an individual IP address to the container?

By default, the container uses bridge networking, which shares the IP address with the host.
Expand Down
137 changes: 67 additions & 70 deletions src/network.sh
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Original file line number Diff line number Diff line change
Expand Up @@ -181,35 +181,26 @@ configureDNS() {
return 0
}

getUserPorts() {

local args=""
local list=$1
local ssh="22"

[[ "${BOOT_MODE:-}" == "windows"* ]] && ssh="3389"
[ -z "$list" ] && list="$ssh" || list+=",$ssh"
compat() {

list="${list//,/ }"
list="${list## }"
list="${list%% }"
local gateway="$1"
local interface="$2"
local samba="20.20.20.1"

for port in $list; do
proto="tcp"
num="$port"
[[ "$samba" == "$gateway" ]] && return 0
[[ "${BOOT_MODE:-}" != "windows"* ]] && return 0

if [[ "$port" == */udp ]]; then
proto="udp"
num="${port%/udp}"
elif [[ "$port" == */tcp ]]; then
proto="tcp"
num="${port%/tcp}"
fi
if [[ "$interface" != "${interface:0:8}" ]]; then
error "Bridge name too long!" && return 1
fi

args+="hostfwd=$proto::$num-$VM_NET_IP:$num,"
done
# Backwards compatibility with old installations
if ip address add dev "$interface" "$samba/24" label "$interface:compat"; then
SAMBA_INTERFACE="$samba"
else
warn "failed to configure IP alias!"
fi

echo "${args%?}"
return 0
}

Expand All @@ -233,47 +224,52 @@ getHostPorts() {
[ -z "$list" ] && list="$WSD_PORT" || list+=",$WSD_PORT"
fi

if [[ "${NETWORK,,}" == "passt" ]]; then

local DNS_PORT="53"
local SAMBA_PORT="445"
echo "$list"
return 0
}

if [[ "${DNSMASQ_DISABLE:-}" != [Yy1]* ]]; then
[ -z "$list" ] && list="$DNS_PORT" || list+=",$DNS_PORT"
fi
getUserPorts() {

if [[ "${BOOT_MODE:-}" == "windows"* ]]; then
if [[ "${SAMBA:-}" != [Nn]* ]]; then
[ -z "$list" ] && list="$SAMBA_PORT" || list+=",$SAMBA_PORT"
fi
fi
local args=""
local list=$1
list=$(echo "${list// /}" | sed 's/,*$//g')

fi
local ssh="22"
[[ "${BOOT_MODE:-}" == "windows"* ]] && ssh="3389"
[ -z "$list" ] && list="$ssh" || list+=",$ssh"

echo "$list"
return 0
}

compat() {
getSlirp() {

local gateway="$1"
local interface="$2"
local samba="20.20.20.1"
local args=""
local list=""

[[ "$samba" == "$gateway" ]] && return 0
[[ "${BOOT_MODE:-}" != "windows"* ]] && return 0
list=$(getUserPorts)
list="${list//,/ }"
list="${list## }"
list="${list%% }"

if [[ "$interface" != "${interface:0:8}" ]]; then
error "Bridge name too long!" && return 1
fi
for port in $list; do

# Backwards compatibility with old installations
if ip address add dev "$interface" "$samba/24" label "$interface:compat"; then
SAMBA_INTERFACE="$samba"
else
warn "failed to configure IP alias!"
fi
proto="tcp"
num="${port%/tcp}"

if [[ "$port" == *"/udp" ]]; then
proto="udp"
num="${port%/udp}"
elif [[ "$port" != *"/tcp" ]]; then
args+="hostfwd=$proto::$num-$VM_NET_IP:$num,"
proto="udp"
num="${port%/udp}"
fi

args+="hostfwd=$proto::$num-$VM_NET_IP:$num,"
done

echo "${args%?}"
return 0
}

Expand All @@ -295,14 +291,14 @@ configureSlirp() {

NET_OPTS="-netdev user,id=hostnet0,ipv4=on,host=$gateway,net=${gateway%.*}.0/24,dhcpstart=$ip,${ipv6}hostname=$VM_NET_HOST"

local forward
local forward=""
forward=$(getUserPorts "${USER_PORTS:-}")
[ -n "$forward" ] && NET_OPTS+=",$forward"

if [[ "${DNSMASQ_DISABLE:-}" != [Yy1]* ]]; then
cp /etc/resolv.conf /etc/resolv.dnsmasq
echo -e "nameserver 127.0.0.1\nsearch .\noptions ndots:0" >/etc/resolv.conf
configureDNS "lo" "$ip" "$VM_NET_MAC" "$VM_NET_HOST" "$VM_NET_MASK" "$gateway" || return 1
echo -e "nameserver 127.0.0.1\nsearch .\noptions ndots:0" >/etc/resolv.conf
fi

VM_NET_IP="$ip"
Expand Down Expand Up @@ -340,16 +336,17 @@ configurePasst() {
PASST_OPTS+=" -n $VM_NET_MASK"
[ -n "$PASST_MTU" ] && PASST_OPTS+=" -m $PASST_MTU"

exclude=$(getHostPorts "$HOST_PORTS")
local forward=""
forward=$(getUserPorts "${USER_PORTS:-}")
forward="${forward///tcp}"
forward="${forward///udp}"

if [ -z "$exclude" ]; then
exclude="%${VM_NET_DEV}/all"
else
exclude="%${VM_NET_DEV}/~${exclude//,/,~}"
if [ -n "$forward" ]; then
forward="%${VM_NET_DEV}/$forward"
PASST_OPTS+=" -t $forward"
PASST_OPTS+=" -u $forward"
fi

PASST_OPTS+=" -t $exclude"
PASST_OPTS+=" -u $exclude"
PASST_OPTS+=" -H $VM_NET_HOST"
PASST_OPTS+=" -M $GATEWAY_MAC"
PASST_OPTS+=" -P /var/run/passt.pid"
Expand Down Expand Up @@ -701,11 +698,6 @@ getInfo() {
[ -z "$MTU" ] && MTU="$mtu"
[ -z "$MTU" ] && MTU="0"

if [ "$MTU" -gt "1500" ]; then
[[ "$DEBUG" == [Yy1]* ]] && echo "MTU size is too large: $MTU, ignoring..."
MTU="0"
fi

if [[ "${ADAPTER,,}" != "virtio-net-pci" ]]; then
if [[ "$MTU" != "0" && "$MTU" != "1500" ]]; then
warn "MTU size is $MTU, but cannot be set for $ADAPTER adapters!" && MTU="0"
Expand Down Expand Up @@ -821,16 +813,21 @@ else
if ! configureSlirp; then
error "Failed to configure user-mode networking!"
exit 24
fi

if [ -z "$USER_PORTS" ]; then
info "Notice: slirp networking is active, so when you want to expose ports, you will need to map them using this variable: \"USER_PORTS=80,443\"."
fi ;;

*)
error "Unrecognized NETWORK value: \"$NETWORK\"" && exit 24 ;;
esac

case "${NETWORK,,}" in
"passt" | "slirp" )

if [ -z "$USER_PORTS" ]; then
info "Notice: because user-mode networking is active, if you need to expose ports, add them to the \"USER_PORTS\" variable."
fi ;;

esac

fi

NET_OPTS+=" -device $ADAPTER,id=net0,netdev=hostnet0,romfile=,mac=$VM_NET_MAC"
Expand Down