debvm-run: add a --netopt option to customize the -netdev

1 files changed, 19 insertions, 10 deletions

diff --git a/bin/debvm-run b/bin/debvm-run
index ddd6d1f..f2b4587 100755
--- a/bin/debvm-run
+++ b/bin/debvm-run
@@ -35,6 +35,14 @@ Note that B<debvm-create> defaults to installing a cloud kernel if available, so
 This option specifies the location of the virtual machine image file.
 By default F<rootfs.ext4> in the working directory is used.
 
+=item B<--netopt>=I<option>
+
+B<debvm-run> sets up a user mode network by default.
+It therefore passes a B<-netdev> option to B<qemu>.
+Using this option, you can customize the value of that B<-netdev> option.
+For instance, you can set up additional port forwards by passing e.g. C<--netopt hostfwd=:127.0.0.1:8080-:80>.
+It can be used multiple times.
+
 =item B<-s> I<sshport>, B<--sshport>=I<sshport>
 
 If given, B<qemu> is configured to pass connections to I<127.0.0.1:sshport> to port 22 of the virtual machine.
@@ -42,6 +50,8 @@ You can connect to your virtual machine without updating your known hosts like t
 
     ssh -o NoHostAuthenticationForLocalhost=yes -p $sshport root@127.0.0.1
 
+The option is a shorthand for C<--netopt hostfwd=tcp:127.0.0.1:sshport-:22>.
+
 =item B<--> I<qemu options>
 
 All options beyond a double dash are passed to B<qemu>.
@@ -94,8 +104,8 @@ POD2MAN
 set -u
 
 IMAGE=rootfs.ext4
-SSHPORT=
 GRAPHICAL=
+NETOPTS=
 
 nth_arg() {
 	shift "$1"
@@ -128,8 +138,11 @@ opt_graphical() {
 opt_image() {
 	IMAGE=$1
 }
+opt_netopt() {
+	NETOPTS="$NETOPTS,$1"
+}
 opt_sshport() {
-	SSHPORT=$1
+	opt_netopt "hostfwd=tcp:127.0.0.1:$1-:22"
 }
 
 while getopts :gi:s:-: OPTCHAR; do
@@ -145,12 +158,12 @@ while getopts :gi:s:-: OPTCHAR; do
 				graphical)
 					"opt_$OPTARG"
 				;;
-				image|sshport)
+				image|netopt|sshport)
 					test "$OPTIND" -gt "$#" && usage_error "missing argument for --$OPTARG"
 					"opt_$OPTARG" "$(nth_arg "$OPTIND" "$@")"
 					OPTIND=$((OPTIND+1))
 				;;
-				image=*|sshport=*)
+				image=*|netopt=*|sshport=*)
 					"opt_${OPTARG%%=*}" "${OPTARG#*=}"
 				;;
 				*)
@@ -244,7 +257,6 @@ case "$IMAGE_LABEL" in
 esac
 
 KERNEL_CMDLINE="root=LABEL=$IMAGE_LABEL rw"
-NETDEV="user,id=net0"
 
 KERNELFD=3
 while test -h "/proc/self/fd/$KERNELFD"; do
@@ -390,16 +402,13 @@ else
 		"$@"
 fi
 
-if test -n "$SSHPORT"; then
-	NETDEV="$NETDEV,hostfwd=tcp:127.0.0.1:$SSHPORT-:22"
-fi
 DNSSEARCH=$(dnsdomainname)
 if test -n "$DNSSEARCH"; then
-	NETDEV="$NETDEV,domainname=$DNSSEARCH"
+	NETOPTS=",domainname=$DNSSEARCH$NETOPTS"
 fi
 set -- \
 	-append "$KERNEL_CMDLINE" \
-	-netdev "$NETDEV" \
+	-netdev "user,id=net0$NETOPTS" \
 	-device "$NIC_DEV" \
 	"$@"