Skip to content

Commit

Permalink
Templatize the vm config, and misc hardening
Browse files Browse the repository at this point in the history
  • Loading branch information
Daniel Hiltgen committed Sep 12, 2015
1 parent 6a6844c commit d860ddf
Showing 1 changed file with 90 additions and 54 deletions.
144 changes: 90 additions & 54 deletions kvm.go
View file
Original file line number Diff line number Diff line change
Expand Up @@ -13,9 +13,9 @@ import (
"os"
"path/filepath"
"strings"
"text/template"
"time"

// "github.com/codegangsta/cli"
"github.com/docker/machine/libmachine/drivers"
"github.com/docker/machine/libmachine/log"
"github.com/docker/machine/libmachine/mcnflag"
Expand All @@ -32,10 +32,9 @@ const (
dnsmasqLeases = "/var/lib/libvirt/dnsmasq/%s.leases"
dnsmasqStatus = "/var/lib/libvirt/dnsmasq/%s.status"

// TODO - Switch to template based instead of sprintf substitution
domainXML = `<domain type='kvm'>
<name>%s</name> <memory unit='M'>%d</memory>
<vcpu>%d</vcpu>
domainXMLTemplate = `<domain type='kvm'>
<name>{{.MachineName}}</name> <memory unit='M'>{{.Memory}}</memory>
<vcpu>{{.CPU}}</vcpu>
<features><acpi/><apic/><pae/></features>
<os>
<type>hvm</type>
Expand All @@ -45,22 +44,22 @@ const (
</os>
<devices>
<disk type='file' device='cdrom'>
<source file='%s'/>
<source file='{{.ISO}}'/>
<target dev='hdc' bus='ide'/>
<readonly/>
</disk>
<disk type='file' device='disk'>
<source file='%s'/>
<source file='{{.DiskPath}}'/>
<target dev='hda' bus='ide'/>
</disk>
<graphics type='vnc' autoport='yes' listen='127.0.0.1'>
<listen type='address' address='127.0.0.1'/>
</graphics>
<interface type='network'>
<source network='%s'/>
<source network='{{.Network}}'/>
</interface>
<interface type='network'>
<source network='%s'/>
<source network='{{.PrivateNetwork}}'/>
</interface>
</devices>
</domain>`
Expand All @@ -81,10 +80,12 @@ type Driver struct {
DiskSize int
CPU int
Network string
PrivateNetwork string
ISO string
Boot2DockerURL string
CaCertPath string
PrivateKeyPath string
DiskPath string
connectionString string
conn *libvirt.VirConnection
VM *libvirt.VirDomain
Expand All @@ -93,19 +94,6 @@ type Driver struct {

func (d *Driver) GetCreateFlags() []mcnflag.Flag {
return []mcnflag.Flag{
/*
* Can't support this at present due to filesystem assumptions
* If we can figure out how to copy the disk image up
* to the remote system, then we could support remote libvirt
* instances
*/
/*
mcnflag.Flag{
Name: "kvm-connection",
Usage: "The libvirt connection string",
Value: "qemu:///system",
},
*/
mcnflag.Flag{
Name: "kvm-memory",
Usage: "Size of memory for host in MB",
Expand Down Expand Up @@ -133,6 +121,12 @@ func (d *Driver) GetCreateFlags() []mcnflag.Flag {
Usage: "The URL of the boot2docker image. Defaults to the latest available version",
Value: "",
},
/* Not yet implemented
mcnflag.Flag{
Name: "kvm-no-share",
Usage: "Disable the mount of your home directory",
},
*/
}
}

Expand Down Expand Up @@ -179,10 +173,10 @@ func (d *Driver) SetConfigFromFlags(flags drivers.DriverOptions) error {
d.SwarmMaster = flags.Bool("swarm-master")
d.SwarmHost = flags.String("swarm-host")
d.SwarmDiscovery = flags.String("swarm-discovery")
d.ISO = filepath.Join(d.LocalArtifactPath("."), isoFilename)
d.SSHUser = "docker"
d.SSHPort = 22
d.ISO = filepath.Join(d.LocalArtifactPath("."), isoFilename)

d.DiskPath = filepath.Join(d.LocalArtifactPath("."), fmt.Sprintf("%s.img", d.MachineName))
return nil
}

Expand All @@ -196,25 +190,62 @@ func (d *Driver) GetURL() (string, error) {
if ip == "" {
return "", nil
}
return fmt.Sprintf("tcp://%s:2376", ip), nil
return fmt.Sprintf("tcp://%s:2376", ip), nil // TODO - don't hardcode the port!
}

// Create, or verify the private network is properly configured
func (d *Driver) validatePrivateNetwork() error {
log.Debug("Validating private network")
_, err := d.conn.LookupNetworkByName(privateNetworkName)
network, err := d.conn.LookupNetworkByName(d.PrivateNetwork)
if err == nil {
// TODO - validate the proper configuration
xmldoc, err := network.GetXMLDesc(0)
if err != nil {
return err
}
/* XML structure:
<network>
...
<ip address='a.b.c.d' netmask='255.255.255.0'>
<dhcp>
<range start='a.b.c.d' end='w.x.y.z'/>
</dhcp>
*/
type Ip struct {
Address string `xml:"address,attr"`
Netmask string `xml:"netmask,attr"`
}
type Network struct {
Ip Ip `xml:"ip"`
}

var nw Network
err = xml.Unmarshal([]byte(xmldoc), &nw)
if err != nil {
return err
}

if nw.Ip.Address == "" {
return fmt.Errorf("%s network doesn't have DHCP configured properly", d.PrivateNetwork)
}
// Corner case, but might happen...
if active, err := network.IsActive(); !active {
log.Debugf("Reactivating private network: %s", err)
err = network.Create()
if err != nil {
log.Warnf("Failed to Start network: %s", err)
return err
}
}
return nil
}
// TODO - try a couple pre-defined networks and look for conflicts before
// settling on one
xml := fmt.Sprintf(networkXML, privateNetworkName,
xml := fmt.Sprintf(networkXML, d.PrivateNetwork,
"192.168.42.1",
"255.255.255.0",
"192.168.42.2",
"192.168.42.254")
network, err := d.conn.NetworkDefineXML(xml)
network, err = d.conn.NetworkDefineXML(xml)
if err != nil {
log.Errorf("Failed to create private network: %s", err)
return nil
Expand Down Expand Up @@ -242,8 +273,8 @@ func (d *Driver) validateNetwork(name string) error {
}

func (d *Driver) PreCreateCheck() error {
// We could look at d.conn.GetCapabilities()
// parse the XML, and look for hypervisors we care about
// TODO We could look at d.conn.GetCapabilities()
// parse the XML, and look for kvm

log.Debug("About to check libvirt version")

Expand Down Expand Up @@ -302,10 +333,17 @@ func (d *Driver) Create() error {
}

log.Debugf("Defining VM...")
// TODO Needs love for other tunables users might want to tweak
xml := fmt.Sprintf(domainXML, d.MachineName, d.Memory, d.CPU,
d.ISO, d.diskPath(), d.Network, privateNetworkName)
vm, err := d.conn.DomainDefineXML(xml)
tmpl, err := template.New("domain").Parse(domainXMLTemplate)
if err != nil {
return err
}
var xml bytes.Buffer
err = tmpl.Execute(&xml, d)
if err != nil {
return err
}

vm, err := d.conn.DomainDefineXML(xml.String())
if err != nil {
log.Warnf("Failed to create the VM: %s", err)
return err
Expand Down Expand Up @@ -443,17 +481,18 @@ func (d *Driver) getMAC() (string, error) {
if err != nil {
return "", err
}
// XML structure:
// <domain>
// ...
// <devices>
// ...
// <interface type='network'>
// ...
// <mac address='52:54:00:d2:3f:ba'/>
// ...
// </interface>
// ...
/* XML structure:
<domain>
...
<devices>
...
<interface type='network'>
...
<mac address='52:54:00:d2:3f:ba'/>
...
</interface>
...
*/
type Mac struct {
Address string `xml:"address,attr"`
}
Expand Down Expand Up @@ -483,7 +522,7 @@ func (d *Driver) getMAC() (string, error) {
}

func (d *Driver) getIPByMACFromLeaseFile(mac string) (string, error) {
leaseFile := fmt.Sprintf(dnsmasqLeases, privateNetworkName)
leaseFile := fmt.Sprintf(dnsmasqLeases, d.PrivateNetwork)
data, err := ioutil.ReadFile(leaseFile)
if err != nil {
log.Debugf("Failed to retrieve dnsmasq leases from %s", leaseFile)
Expand All @@ -507,7 +546,7 @@ func (d *Driver) getIPByMACFromLeaseFile(mac string) (string, error) {
}

func (d *Driver) getIPByMacFromSettings(mac string) (string, error) {
network, err := d.conn.LookupNetworkByName(privateNetworkName)
network, err := d.conn.LookupNetworkByName(d.PrivateNetwork)
if err != nil {
log.Warnf("Failed to find network: %s", err)
return "", err
Expand All @@ -522,7 +561,7 @@ func (d *Driver) getIPByMacFromSettings(mac string) (string, error) {
type Lease struct {
Ip_address string `json:"ip-address"`
Mac_address string `json:"mac-address"`
/* Other unused fields omitted */
// Other unused fields omitted
}
var s []Lease

Expand Down Expand Up @@ -561,10 +600,6 @@ func (d *Driver) publicSSHKeyPath() string {
return d.GetSSHKeyPath() + ".pub"
}

func (d *Driver) diskPath() string {
return filepath.Join(d.LocalArtifactPath("."), fmt.Sprintf("%s.img", d.MachineName))
}

// Make a boot2docker VM disk image.
func (d *Driver) generateDiskImage(size int) error {
log.Debugf("Creating %d MB hard disk image...", size)
Expand Down Expand Up @@ -609,7 +644,7 @@ func (d *Driver) generateDiskImage(size int) error {
return err
}
raw := bytes.NewReader(buf.Bytes())
return createDiskImage(d.diskPath(), size, raw)
return createDiskImage(d.DiskPath, size, raw)
}

// createDiskImage makes a disk image at dest with the given size in MB. If r is
Expand Down Expand Up @@ -639,5 +674,6 @@ func NewDriver() *Driver {
log.Fatalf("Failed to connect to libvirt: %s", err)
}
d.conn = &conn
d.PrivateNetwork = privateNetworkName
return d
}

0 comments on commit d860ddf

Please sign in to comment.