host-device: add deviceID property

Fixes #253

plugins/main/host-device/README.md

@@ -1,17 +1,25 @@
 # host-device
+
 Move an already-existing device into a container.
 
-This simple plugin will move the requested device from the host's network namespace
+## Overview
-to the container's. Nothing else will be done - no IPAM, no addresses.
 
-The device can be specified with any one of three properties:
+This simple plugin will move the requested device from the host's network namespace
+to the container's. IPAM configuration can be used for this plugin.
+
+## Network configuration reference
+
+The device can be specified with any one of four properties:
 * `device`: The device name, e.g. `eth0`, `can0`
 * `hwaddr`: A MAC address
 * `kernelpath`: The kernel device kobj, e.g. `/sys/devices/pci0000:00/0000:00:1f.6`
+* `pciBusID`: A PCI address of network device, e.g `0000:00:1f.6`
 
 For this plugin, `CNI_IFNAME` will be ignored. Upon DEL, the device will be moved back.
 
-A sample configuration might look like:
+## Example configuration
+
+A sample configuration with `device` property looks like:
 
 ```json
 {
@@ -20,3 +28,13 @@ A sample configuration might look like:
 	"device": "enp0s1"
 }
 ```
+
+A sample configuration with `pciBusID` property looks like:
+
+```json
+{
+	"cniVersion": "0.3.1",
+	"type": "host-device",
+	"pciBusID": "0000:3d:00.1"
+}
+```

plugins/main/host-device/host-device.go

@@ -21,6 +21,7 @@ import (
 	"fmt"
 	"io/ioutil"
 	"net"
+	"os"
 	"path/filepath"
 	"runtime"
 	"strings"
@@ -38,12 +39,17 @@ import (
 	bv "github.com/containernetworking/plugins/pkg/utils/buildversion"
 )
 
+const (
+	sysBusPCI = "/sys/bus/pci/devices"
+)
+
 //NetConf for host-device config, look the README to learn how to use those parameters
 type NetConf struct {
 	types.NetConf
 	Device     string `json:"device"`     // Device-Name, something like eth0 or can0 etc.
 	HWAddr     string `json:"hwaddr"`     // MAC Address of target network interface
 	KernelPath string `json:"kernelpath"` // Kernelpath of the device
+	PCIAddr    string `json:"pciBusID"`   // PCI Address of target network device
 }
 
 func init() {
@@ -58,8 +64,8 @@ func loadConf(bytes []byte) (*NetConf, error) {
 	if err := json.Unmarshal(bytes, n); err != nil {
 		return nil, fmt.Errorf("failed to load netconf: %v", err)
 	}
-	if n.Device == "" && n.HWAddr == "" && n.KernelPath == "" {
+	if n.Device == "" && n.HWAddr == "" && n.KernelPath == "" && n.PCIAddr == "" {
-		return nil, fmt.Errorf(`specify either "device", "hwaddr" or "kernelpath"`)
+		return nil, fmt.Errorf(`specify either "device", "hwaddr", "kernelpath" or "pciBusID"`)
 	}
 	return n, nil
 }
@@ -75,7 +81,7 @@ func cmdAdd(args *skel.CmdArgs) error {
 	}
 	defer containerNs.Close()
 
-	hostDev, err := getLink(cfg.Device, cfg.HWAddr, cfg.KernelPath)
+	hostDev, err := getLink(cfg.Device, cfg.HWAddr, cfg.KernelPath, cfg.PCIAddr)
 	if err != nil {
 		return fmt.Errorf("failed to find host device: %v", err)
 	}
@@ -240,7 +246,7 @@ func printLink(dev netlink.Link, cniVersion string, containerNs ns.NetNS) error
 	return types.PrintResult(&result, cniVersion)
 }
 
-func getLink(devname, hwaddr, kernelpath string) (netlink.Link, error) {
+func getLink(devname, hwaddr, kernelpath, pciaddr string) (netlink.Link, error) {
 	links, err := netlink.LinkList()
 	if err != nil {
 		return nil, fmt.Errorf("failed to list node links: %v", err)
@@ -278,6 +284,19 @@ func getLink(devname, hwaddr, kernelpath string) (netlink.Link, error) {
 				}
 			}
 		}
+	} else if len(pciaddr) > 0 {
+		netDir := filepath.Join(sysBusPCI, pciaddr, "net")
+		if _, err := os.Lstat(netDir); err != nil {
+			return nil, fmt.Errorf("no net directory under pci device %s: %q", pciaddr, err)
+		}
+		fInfo, err := ioutil.ReadDir(netDir)
+		if err != nil {
+			return nil, fmt.Errorf("failed to read net directory %s: %q", netDir, err)
+		}
+		if len(fInfo) > 0 {
+			return netlink.LinkByName(fInfo[0].Name())
+		}
+		return nil, fmt.Errorf("failed to find device name for pci address %s", pciaddr)
 	}
 
 	return nil, fmt.Errorf("failed to find physical interface")

plugins/main/host-device/host-device_test.go

@@ -40,6 +40,7 @@ type Net struct {
 	Device        string                 `json:"device"`     // Device-Name, something like eth0 or can0 etc.
 	HWAddr        string                 `json:"hwaddr"`     // MAC Address of target network interface
 	KernelPath    string                 `json:"kernelpath"` // Kernelpath of the device
+	PCIAddr       string                 `json:"pciBusID"`   // PCI Address of target network device
 	IPAM          *IPAMConfig            `json:"ipam,omitempty"`
 	DNS           types.DNS              `json:"dns"`
 	RawPrevResult map[string]interface{} `json:"prevResult,omitempty"`
@@ -449,7 +450,7 @@ var _ = Describe("base functionality", func() {
 			StdinData:   []byte(conf),
 		}
 		_, _, err := testutils.CmdAddWithArgs(args, func() error { return cmdAdd(args) })
-		Expect(err).To(MatchError(`specify either "device", "hwaddr" or "kernelpath"`))
+		Expect(err).To(MatchError(`specify either "device", "hwaddr", "kernelpath" or "pciBusID"`))
 
 	})