wip: migrate to mono-repo. SPN has already been moved to spn/

spn/navigator/routing-profiles.go

@@ -0,0 +1,162 @@
+package navigator
+
+import (
+	"github.com/safing/portbase/log"
+	"github.com/safing/portmaster/service/profile"
+)
+
+// RoutingProfile defines a routing algorithm with some options.
+type RoutingProfile struct {
+	ID string
+
+	// Name is the human readable name of the profile.
+	Name string
+
+	// MinHops defines how many hops a route must have at minimum. In order to
+	// reduce confusion, the Home Hub is also counted.
+	MinHops int
+
+	// MaxHops defines the limit on how many hops a route may have. In order to
+	// reduce confusion, the Home Hub is also counted.
+	MaxHops int
+
+	// MaxExtraHops sets a limit on how many extra hops are allowed in addition
+	// to the amount of Hops in the currently best route. This is an optimization
+	// option and should not interfere with finding the best route, but might
+	// reduce the amount of routes found.
+	MaxExtraHops int
+
+	// MaxExtraCost sets a limit on the extra cost allowed in addition to the
+	// cost of the currently best route. This is an optimization option and
+	// should not interfere with finding the best route, but might reduce the
+	// amount of routes found.
+	MaxExtraCost float32
+}
+
+// Routing Profile Names.
+const (
+	RoutingProfileHomeID      = "home"
+	RoutingProfileSingleHopID = "single-hop"
+	RoutingProfileDoubleHopID = "double-hop"
+	RoutingProfileTripleHopID = "triple-hop"
+)
+
+// Routing Profiles.
+var (
+	DefaultRoutingProfileID = profile.DefaultRoutingProfileID
+
+	RoutingProfileHome = &RoutingProfile{
+		ID:      "home",
+		Name:    "Plain VPN Mode",
+		MinHops: 1,
+		MaxHops: 1,
+	}
+	RoutingProfileSingleHop = &RoutingProfile{
+		ID:           "single-hop",
+		Name:         "Speed Focused",
+		MinHops:      1,
+		MaxHops:      3,
+		MaxExtraHops: 1,
+		MaxExtraCost: 10000,
+	}
+	RoutingProfileDoubleHop = &RoutingProfile{
+		ID:           "double-hop",
+		Name:         "Balanced",
+		MinHops:      2,
+		MaxHops:      4,
+		MaxExtraHops: 2,
+		MaxExtraCost: 10000,
+	}
+	RoutingProfileTripleHop = &RoutingProfile{
+		ID:           "triple-hop",
+		Name:         "Privacy Focused",
+		MinHops:      3,
+		MaxHops:      5,
+		MaxExtraHops: 3,
+		MaxExtraCost: 10000,
+	}
+)
+
+// GetRoutingProfile returns the routing profile with the given ID.
+func GetRoutingProfile(id string) *RoutingProfile {
+	switch id {
+	case RoutingProfileHomeID:
+		return RoutingProfileHome
+	case RoutingProfileSingleHopID:
+		return RoutingProfileSingleHop
+	case RoutingProfileDoubleHopID:
+		return RoutingProfileDoubleHop
+	case RoutingProfileTripleHopID:
+		return RoutingProfileTripleHop
+	default:
+		return RoutingProfileDoubleHop
+	}
+}
+
+type routeCompliance uint8
+
+const (
+	routeOk           routeCompliance = iota // Route is fully compliant and can be used.
+	routeNonCompliant                        // Route is not compliant, but this might change if more hops are added.
+	routeDisqualified                        // Route is disqualified and won't be able to become compliant.
+)
+
+func (rp *RoutingProfile) checkRouteCompliance(route *Route, foundRoutes *Routes) routeCompliance {
+	switch {
+	case len(route.Path) < rp.MinHops:
+		// Route is shorter than the defined minimum.
+		return routeNonCompliant
+	case len(route.Path) > rp.MaxHops:
+		// Route is longer than the defined maximum.
+		return routeDisqualified
+	}
+
+	// Check for hub re-use.
+	if len(route.Path) >= 2 {
+		lastHop := route.Path[len(route.Path)-1]
+		for _, hop := range route.Path[:len(route.Path)-1] {
+			if lastHop.pin.Hub.ID == hop.pin.Hub.ID {
+				return routeDisqualified
+			}
+		}
+	}
+
+	// Check if hub is already in use, if so check if the route matches.
+	if len(route.Path) >= 2 {
+		// Get active connection to the last pin of the current path.
+		lastPinConnection := route.Path[len(route.Path)-1].pin.Connection
+
+		switch {
+		case lastPinConnection == nil:
+			// Last pin is not yet connected.
+		case len(lastPinConnection.Route.Path) < 2:
+			// Path of last pin does not have enough hops.
+			// This is unexpected and should not happen.
+			log.Errorf(
+				"navigator: expected active connection to %s to have 2 hops or more on path, but it had %d",
+				route.Path[len(route.Path)-1].pin.Hub.StringWithoutLocking(),
+				len(lastPinConnection.Route.Path),
+			)
+		case lastPinConnection.Route.Path[len(lastPinConnection.Route.Path)-2].pin.Hub.ID != route.Path[len(route.Path)-2].pin.Hub.ID:
+			// The previous hop of the existing route and the one we are evaluating don't match.
+			// Currently, we only allow one session per Hub.
+			return routeDisqualified
+		}
+	}
+
+	// Abort route exploration when we are outside the optimization boundaries.
+	if len(foundRoutes.All) > 0 {
+		// Get the best found route.
+		best := foundRoutes.All[0]
+		// Abort if current route exceeds max extra costs.
+		if route.TotalCost > best.TotalCost+rp.MaxExtraCost {
+			return routeDisqualified
+		}
+		// Abort if current route exceeds max extra hops.
+		if len(route.Path) > len(best.Path)+rp.MaxExtraHops {
+			return routeDisqualified
+		}
+	}
+
+	return routeOk
+}