[management] network map from nmap data type (#6919)

Signed-off-by: Dmitri Dolguikh <dmitri.external@netbird.io>
Co-authored-by: Dmitri Dolguikh <dmitri.external@netbird.io>

shared/management/networkmap/nmdata/posture_network.go

@@ -0,0 +1,62 @@
+package nmdata
+
+import (
+	"fmt"
+	"net/netip"
+)
+
+// PeerNetworkRangeCheck is the slim twin of posture.PeerNetworkRangeCheck.
+type PeerNetworkRangeCheck struct {
+	Action string
+	Ranges []netip.Prefix
+}
+
+func (p *PeerNetworkRangeCheck) check(peer *Peer) (bool, error) {
+	peerPrefixes := make([]netip.Prefix, 0, len(peer.Meta.NetworkAddresses)+1)
+	for _, peerNetAddr := range peer.Meta.NetworkAddresses {
+		peerPrefixes = append(peerPrefixes, peerNetAddr.NetIP)
+	}
+	if connIP := peer.Location.ConnectionIP; len(connIP) > 0 {
+		if addr, ok := netip.AddrFromSlice(connIP); ok {
+			addr = addr.Unmap()
+			peerPrefixes = append(peerPrefixes, netip.PrefixFrom(addr, addr.BitLen()))
+		}
+	}
+
+	if len(peerPrefixes) == 0 {
+		return false, fmt.Errorf("peer's does not contain peer network range addresses")
+	}
+
+	for _, peerPrefix := range peerPrefixes {
+		for _, rangePrefix := range p.Ranges {
+			if !prefixContains(rangePrefix, peerPrefix) {
+				continue
+			}
+			switch p.Action {
+			case checkActionDeny:
+				return false, nil
+			case checkActionAllow:
+				return true, nil
+			default:
+				return false, fmt.Errorf("invalid peer network range check action: %s", p.Action)
+			}
+		}
+	}
+
+	if p.Action == checkActionDeny {
+		return true, nil
+	}
+	if p.Action == checkActionAllow {
+		return false, nil
+	}
+
+	return false, fmt.Errorf("invalid peer network range check action: %s", p.Action)
+}
+
+func prefixContains(outer, inner netip.Prefix) bool {
+	outer = outer.Masked()
+	inner = inner.Masked()
+	return outer.Bits() <= inner.Bits() &&
+		outer.Addr().BitLen() == inner.Addr().BitLen() &&
+		outer.Contains(inner.Addr())
+}