net_extender_profiles.go

package connect

import (
	mathrand "math/rand"

	"golang.org/x/exp/maps"
)

// randomly enumerate up to n extender profiles
func EnumerateExtenderProfiles(n int, visited map[ExtenderProfile]bool) []ExtenderProfile {
	out := map[ExtenderProfile]bool{}

	type persona struct {
		hosts            []string
		portConnectModes map[int][]ExtenderConnectMode
	}

	personas := []*persona{}
	if 0 < len(mailHosts) && 0 < len(mailPorts) {
		personas = append(personas, &persona{
			hosts:            mailHosts,
			portConnectModes: mailPorts,
		})
	}
	if 0 < len(serviceHosts) && 0 < len(servicePorts) {
		personas = append(personas, &persona{
			hosts:            serviceHosts,
			portConnectModes: servicePorts,
		})
	}

	if 0 < len(personas) {
		maxIterations := 32 * n
		for i := 0; len(out) < n && i < maxIterations; i += 1 {
			persona := personas[mathrand.Intn(len(personas))]

			ports := maps.Keys(persona.portConnectModes)
			port := ports[mathrand.Intn(len(ports))]
			connectModes := persona.portConnectModes[port]
			connectMode := connectModes[mathrand.Intn(len(connectModes))]

			var profile ExtenderProfile
			switch connectMode {
			// TODO Udp does not use a host
			default:
				host := persona.hosts[mathrand.Intn(len(persona.hosts))]
				fragment := mathrand.Intn(2) != 0
				reorder := mathrand.Intn(2) != 0
				profile = ExtenderProfile{
					ConnectMode: connectMode,
					ServerName:  host,
					Port:        port,
					Fragment:    fragment,
					Reorder:     reorder,
				}
			}
			if _, ok := visited[profile]; !ok {
				if _, ok := out[profile]; !ok {
					out[profile] = true
				}
			}
		}
	}

	return maps.Keys(out)
}

var servicePorts = map[int][]ExtenderConnectMode{
	// https and secure dns
	443: []ExtenderConnectMode{ExtenderConnectModeTcpTls},
	// dns
	853: []ExtenderConnectMode{ExtenderConnectModeTcpTls},
	// ldap
	636: []ExtenderConnectMode{ExtenderConnectModeTcpTls},
	// docker
	2376: []ExtenderConnectMode{ExtenderConnectModeTcpTls},
	// ldap
	3269: []ExtenderConnectMode{ExtenderConnectModeTcpTls},
	// ntp, nts
	4460: []ExtenderConnectMode{ExtenderConnectModeTcpTls},
}

var mailPorts = map[int][]ExtenderConnectMode{
	// imap
	993: []ExtenderConnectMode{ExtenderConnectModeTcpTls},
	// pop
	995: []ExtenderConnectMode{ExtenderConnectModeTcpTls},
	// smtp
	465: []ExtenderConnectMode{ExtenderConnectModeTcpTls},
}

// FIXME load from a bit masked sni-service.gz. We don't want any url fragments to be in the binary
var serviceHosts = []string{}

// FIXME load from bit masked sni-mail.gz. We don't want any url fragments to be in the binary
var mailHosts = []string{}