slackhq_nebula/overlay/tun.go

73 lines
1.9 KiB
Go

package overlay
import (
"net"
"github.com/sirupsen/logrus"
"github.com/slackhq/nebula/config"
"github.com/slackhq/nebula/util"
)
const DefaultMTU = 1300
// TODO: We may be able to remove routines
type DeviceFactory func(c *config.C, l *logrus.Logger, tunCidr *net.IPNet, routines int) (Device, error)
func NewDeviceFromConfig(c *config.C, l *logrus.Logger, tunCidr *net.IPNet, routines int) (Device, error) {
switch {
case c.GetBool("tun.disabled", false):
tun := newDisabledTun(tunCidr, c.GetInt("tun.tx_queue", 500), c.GetBool("stats.message_metrics", false), l)
return tun, nil
default:
return newTun(c, l, tunCidr, routines > 1)
}
}
func NewFdDeviceFromConfig(fd *int) DeviceFactory {
return func(c *config.C, l *logrus.Logger, tunCidr *net.IPNet, routines int) (Device, error) {
return newTunFromFd(c, l, *fd, tunCidr)
}
}
func getAllRoutesFromConfig(c *config.C, cidr *net.IPNet, initial bool) (bool, []Route, error) {
if !initial && !c.HasChanged("tun.routes") && !c.HasChanged("tun.unsafe_routes") {
return false, nil, nil
}
routes, err := parseRoutes(c, cidr)
if err != nil {
return true, nil, util.NewContextualError("Could not parse tun.routes", nil, err)
}
unsafeRoutes, err := parseUnsafeRoutes(c, cidr)
if err != nil {
return true, nil, util.NewContextualError("Could not parse tun.unsafe_routes", nil, err)
}
routes = append(routes, unsafeRoutes...)
return true, routes, nil
}
// findRemovedRoutes will return all routes that are not present in the newRoutes list and would affect the system route table.
// Via is not used to evaluate since it does not affect the system route table.
func findRemovedRoutes(newRoutes, oldRoutes []Route) []Route {
var removed []Route
has := func(entry Route) bool {
for _, check := range newRoutes {
if check.Equal(entry) {
return true
}
}
return false
}
for _, oldEntry := range oldRoutes {
if !has(oldEntry) {
removed = append(removed, oldEntry)
}
}
return removed
}