suggestedOptions.go

// package sam3 wraps the original sam3 API from github.com/go-i2p/sam3
package sam3

import (
	"net"
	"os"
	"strings"

	"github.com/sirupsen/logrus"
)

// Examples and suggestions for options when creating sessions.
var (
	// Suitable options if you are shuffling A LOT of traffic. If unused, this
	// will waste your resources.
	Options_Humongous = []string{
		"inbound.length=3", "outbound.length=3",
		"inbound.lengthVariance=1", "outbound.lengthVariance=1",
		"inbound.backupQuantity=3", "outbound.backupQuantity=3",
		"inbound.quantity=6", "outbound.quantity=6",
	}

	// Suitable for shuffling a lot of traffic.
	Options_Large = []string{
		"inbound.length=3", "outbound.length=3",
		"inbound.lengthVariance=1", "outbound.lengthVariance=1",
		"inbound.backupQuantity=1", "outbound.backupQuantity=1",
		"inbound.quantity=4", "outbound.quantity=4",
	}

	// Suitable for shuffling a lot of traffic quickly with minimum
	// anonymity. Uses 1 hop and multiple tunnels.
	Options_Wide = []string{
		"inbound.length=1", "outbound.length=1",
		"inbound.lengthVariance=1", "outbound.lengthVariance=1",
		"inbound.backupQuantity=2", "outbound.backupQuantity=2",
		"inbound.quantity=3", "outbound.quantity=3",
	}

	// Suitable for shuffling medium amounts of traffic.
	Options_Medium = []string{
		"inbound.length=3", "outbound.length=3",
		"inbound.lengthVariance=1", "outbound.lengthVariance=1",
		"inbound.backupQuantity=0", "outbound.backupQuantity=0",
		"inbound.quantity=2", "outbound.quantity=2",
	}

	// Sensible defaults for most people
	Options_Default = []string{
		"inbound.length=3", "outbound.length=3",
		"inbound.lengthVariance=0", "outbound.lengthVariance=0",
		"inbound.backupQuantity=1", "outbound.backupQuantity=1",
		"inbound.quantity=1", "outbound.quantity=1",
	}

	// Suitable only for small dataflows, and very short lasting connections:
	// You only have one tunnel in each direction, so if any of the nodes
	// through which any of your two tunnels pass through go offline, there will
	// be a complete halt in the dataflow, until a new tunnel is built.
	Options_Small = []string{
		"inbound.length=3", "outbound.length=3",
		"inbound.lengthVariance=1", "outbound.lengthVariance=1",
		"inbound.backupQuantity=0", "outbound.backupQuantity=0",
		"inbound.quantity=1", "outbound.quantity=1",
	}

	// Does not use any anonymization, you connect directly to others tunnel
	// endpoints, thus revealing your identity but not theirs. Use this only
	// if you don't care.
	Options_Warning_ZeroHop = []string{
		"inbound.length=0", "outbound.length=0",
		"inbound.lengthVariance=0", "outbound.lengthVariance=0",
		"inbound.backupQuantity=0", "outbound.backupQuantity=0",
		"inbound.quantity=2", "outbound.quantity=2",
	}
)

func getEnv(key, fallback string) string {
	InitializeSAM3Logger()
	value, ok := os.LookupEnv(key)
	if !ok {
		log.WithFields(logrus.Fields{
			"key":      key,
			"fallback": fallback,
		}).Debug("Environment variable not set, using fallback")
		return fallback
	}
	log.WithFields(logrus.Fields{
		"key":   key,
		"value": value,
	}).Debug("Retrieved environment variable")
	return value
}

var (
	SAM_HOST = getEnv("sam_host", "127.0.0.1")
	SAM_PORT = getEnv("sam_port", "7656")
)

func SAMDefaultAddr(fallforward string) string {
	if fallforward == "" {
		addr := net.JoinHostPort(SAM_HOST, SAM_PORT)
		log.WithField("addr", addr).Debug("Using default SAM address")
		return addr
	}
	log.WithField("addr", fallforward).Debug("Using fallforward SAM address")
	return fallforward
}

func GenerateOptionString(opts []string) string {
	optStr := strings.Join(opts, " ")
	log.WithField("options", optStr).Debug("Generating option string")
	if strings.Contains(optStr, "i2cp.leaseSetEncType") {
		log.Debug("i2cp.leaseSetEncType already present in options")
		return optStr
	}
	finalOpts := optStr + " i2cp.leaseSetEncType=4,0"
	log.WithField("finalOptions", finalOpts).Debug("Added default i2cp.leaseSetEncType to options")
	return finalOpts
	// return optStr + " i2cp.leaseSetEncType=4,0"
}