Merge pull request #33 from safing/feature/remove-random-config

Remove config and use service workers for goroutines

rng/entropy.go

@@ -1,17 +1,20 @@
 package rng
 
 import (
+	"context"
 	"encoding/binary"
 
 	"github.com/tevino/abool"
 
-	"github.com/safing/portbase/config"
 	"github.com/safing/portbase/container"
 )
 
+const (
+	minFeedEntropy = 256
+)
+
 var (
-	rngFeeder      = make(chan []byte)
-	minFeedEntropy config.IntOption
+	rngFeeder = make(chan []byte)
 )
 
 // The Feeder is used to feed entropy to the RNG.
@@ -34,7 +37,7 @@ func NewFeeder() *Feeder {
 		needsEntropy: abool.NewBool(true),
 		buffer:       container.New(),
 	}
-	go new.run()
+	module.StartServiceWorker("feeder", 0, new.run)
 	return new
 }
 
@@ -87,7 +90,7 @@ func (f *Feeder) CloseFeeder() {
 	f.input <- nil
 }
 
-func (f *Feeder) run() {
+func (f *Feeder) run(ctx context.Context) error {
 	defer f.needsEntropy.UnSet()
 
 	for {
@@ -97,23 +100,26 @@ func (f *Feeder) run() {
 		for {
 			select {
 			case newEntropy := <-f.input:
-				if newEntropy != nil {
-					f.buffer.Append(newEntropy.data)
-					f.entropy += int64(newEntropy.entropy)
-					if f.entropy >= minFeedEntropy() {
-						break gather
-					}
+				// check if feed has been closed
+				if newEntropy == nil {
+					return nil
 				}
-			case <-shutdownSignal:
-				return
+				// append to buffer
+				f.buffer.Append(newEntropy.data)
+				f.entropy += int64(newEntropy.entropy)
+				if f.entropy >= minFeedEntropy {
+					break gather
+				}
+			case <-ctx.Done():
+				return nil
 			}
 		}
 		// feed
 		f.needsEntropy.UnSet()
 		select {
 		case rngFeeder <- f.buffer.CompileData():
-		case <-shutdownSignal:
-			return
+		case <-ctx.Done():
+			return nil
 		}
 		f.buffer = container.New()
 	}

rng/fullfeed.go

@@ -1,29 +1,27 @@
 package rng
 
 import (
+	"context"
 	"time"
 )
 
-var (
-	fullFeedDuration = 100 * time.Millisecond
-)
-
 func getFullFeedDuration() time.Duration {
 
 	// full feed every 5x time of reseedAfterSeconds
-	secsUntilFullFeed := reseedAfterSeconds() * 5
+	secsUntilFullFeed := reseedAfterSeconds * 5
 
-	// full feed at most once per minute
-	if secsUntilFullFeed < 60 {
-		secsUntilFullFeed = 60
+	// full feed at most once every ten minutes
+	if secsUntilFullFeed < 600 {
+		secsUntilFullFeed = 600
 	}
 
-	return time.Duration(secsUntilFullFeed * int64(time.Second))
+	return time.Duration(secsUntilFullFeed) * time.Second
 }
 
-func fullFeeder() {
-	for {
+func fullFeeder(ctx context.Context) error {
+	fullFeedDuration := getFullFeedDuration()
 
+	for {
 		select {
 		case <-time.After(fullFeedDuration):
 
@@ -39,11 +37,8 @@ func fullFeeder() {
 			}
 			rngLock.Unlock()
 
-		case <-shutdownSignal:
-			return
+		case <-ctx.Done():
+			return nil
 		}
-
-		fullFeedDuration = getFullFeedDuration()
-
 	}
 }

rng/get.go

@@ -6,19 +6,19 @@ import (
 	"io"
 	"math"
 	"time"
+)
 
-	"github.com/safing/portbase/config"
+const (
+	reseedAfterSeconds = 600     // ten minutes
+	reseedAfterBytes   = 1048576 // one megabyte
 )
 
 var (
 	// Reader provides a global instance to read from the RNG.
 	Reader io.Reader
 
-	rngBytesRead int64
+	rngBytesRead uint64
 	rngLastFeed  = time.Now()
-
-	reseedAfterSeconds config.IntOption
-	reseedAfterBytes   config.IntOption
 )
 
 // reader provides an io.Reader interface
@@ -32,8 +32,8 @@ func checkEntropy() (err error) {
 	if !rngReady {
 		return errors.New("RNG is not ready yet")
 	}
-	if rngBytesRead > reseedAfterBytes() ||
-		int64(time.Since(rngLastFeed).Seconds()) > reseedAfterSeconds() {
+	if rngBytesRead > reseedAfterBytes ||
+		int(time.Since(rngLastFeed).Seconds()) > reseedAfterSeconds {
 		select {
 		case r := <-rngFeeder:
 			rng.Reseed(r)

rng/osfeeder.go

@@ -1,35 +1,36 @@
 package rng
 
 import (
+	"context"
 	"crypto/rand"
-	"time"
-
-	"github.com/safing/portbase/log"
+	"fmt"
 )
 
-func osFeeder() {
+func osFeeder(ctx context.Context) error {
+
+	entropyBytes := minFeedEntropy / 8
 	feeder := NewFeeder()
+	defer feeder.CloseFeeder()
+
 	for {
-
-		// get feed entropy
-		minEntropyBytes := int(minFeedEntropy())/8 + 1
-		if minEntropyBytes < 32 {
-			minEntropyBytes = 64
-		}
-
-		// get entropy
-		osEntropy := make([]byte, minEntropyBytes)
+		// gather
+		osEntropy := make([]byte, entropyBytes)
 		n, err := rand.Read(osEntropy)
 		if err != nil {
-			log.Errorf("could not read entropy from os: %s", err)
-			time.Sleep(10 * time.Second)
+			return fmt.Errorf("could not read entropy from os: %s", err)
 		}
-		if n != minEntropyBytes {
-			log.Errorf("could not read enough entropy from os: got only %d bytes instead of %d", n, minEntropyBytes)
-			time.Sleep(10 * time.Second)
+		if n != entropyBytes {
+			return fmt.Errorf("could not read enough entropy from os: got only %d bytes instead of %d", n, entropyBytes)
 		}
 
 		// feed
-		feeder.SupplyEntropy(osEntropy, minEntropyBytes*8)
+		select {
+		case feeder.input <- &entropyData{
+			data:    osEntropy,
+			entropy: entropyBytes * 8,
+		}:
+		case <-ctx.Done():
+			return nil
+		}
 	}
 }

rng/rng.go

@@ -3,122 +3,60 @@ package rng
 import (
 	"crypto/aes"
 	"crypto/cipher"
+	"errors"
 	"fmt"
 	"sync"
 
 	"github.com/aead/serpent"
 	"github.com/seehuhn/fortuna"
 
-	"github.com/safing/portbase/config"
 	"github.com/safing/portbase/modules"
 )
 
 var (
-	rng             *fortuna.Generator
-	rngLock         sync.Mutex
-	rngReady        = false
-	rngCipherOption config.StringOption
+	rng      *fortuna.Generator
+	rngLock  sync.Mutex
+	rngReady = false
 
-	shutdownSignal = make(chan struct{})
+	rngCipher = "aes"
+	// possible values: aes, serpent
+
+	module *modules.Module
 )
 
 func init() {
-	modules.Register("random", prep, Start, nil)
-}
-
-func prep() error {
-	err := config.Register(&config.Option{
-		Name:            "RNG Cipher",
-		Key:             "random/rng_cipher",
-		Description:     "Cipher to use for the Fortuna RNG. Requires restart to take effect.",
-		OptType:         config.OptTypeString,
-		ExpertiseLevel:  config.ExpertiseLevelDeveloper,
-		ReleaseLevel:    config.ReleaseLevelExperimental,
-		ExternalOptType: "string list",
-		DefaultValue:    "aes",
-		ValidationRegex: "^(aes|serpent)$",
-	})
-	if err != nil {
-		return err
-	}
-	rngCipherOption = config.GetAsString("random/rng_cipher", "aes")
-
-	err = config.Register(&config.Option{
-		Name:            "Minimum Feed Entropy",
-		Key:             "random/min_feed_entropy",
-		Description:     "The minimum amount of entropy before a entropy source is feed to the RNG, in bits.",
-		OptType:         config.OptTypeInt,
-		ExpertiseLevel:  config.ExpertiseLevelDeveloper,
-		ReleaseLevel:    config.ReleaseLevelExperimental,
-		DefaultValue:    256,
-		ValidationRegex: "^[0-9]{3,5}$",
-	})
-	if err != nil {
-		return err
-	}
-	minFeedEntropy = config.Concurrent.GetAsInt("random/min_feed_entropy", 256)
-
-	err = config.Register(&config.Option{
-		Name:            "Reseed after x seconds",
-		Key:             "random/reseed_after_seconds",
-		Description:     "Number of seconds until reseed",
-		OptType:         config.OptTypeInt,
-		ExpertiseLevel:  config.ExpertiseLevelDeveloper,
-		ReleaseLevel:    config.ReleaseLevelExperimental,
-		DefaultValue:    360, // ten minutes
-		ValidationRegex: "^[1-9][0-9]{1,5}$",
-	})
-	if err != nil {
-		return err
-	}
-	reseedAfterSeconds = config.Concurrent.GetAsInt("random/reseed_after_seconds", 360)
-
-	err = config.Register(&config.Option{
-		Name:            "Reseed after x bytes",
-		Key:             "random/reseed_after_bytes",
-		Description:     "Number of fetched bytes until reseed",
-		OptType:         config.OptTypeInt,
-		ExpertiseLevel:  config.ExpertiseLevelDeveloper,
-		ReleaseLevel:    config.ReleaseLevelExperimental,
-		DefaultValue:    1000000, // one megabyte
-		ValidationRegex: "^[1-9][0-9]{2,9}$",
-	})
-	if err != nil {
-		return err
-	}
-	reseedAfterBytes = config.GetAsInt("random/reseed_after_bytes", 1000000)
-
-	return nil
+	module = modules.Register("random", nil, start, nil)
 }
 
 func newCipher(key []byte) (cipher.Block, error) {
-	cipher := rngCipherOption()
-	switch cipher {
+	switch rngCipher {
 	case "aes":
 		return aes.NewCipher(key)
 	case "serpent":
 		return serpent.NewCipher(key)
 	default:
-		return nil, fmt.Errorf("unknown or unsupported cipher: %s", cipher)
+		return nil, fmt.Errorf("unknown or unsupported cipher: %s", rngCipher)
 	}
 }
 
-// Start starts the RNG. Normally, this should be only called by the portbase/modules package.
-func Start() (err error) {
+func start() error {
 	rngLock.Lock()
 	defer rngLock.Unlock()
 
 	rng = fortuna.NewGenerator(newCipher)
+	if rng == nil {
+		return errors.New("failed to initialize rng")
+	}
 	rngReady = true
 
 	// random source: OS
-	go osFeeder()
+	module.StartServiceWorker("os rng feeder", 0, osFeeder)
 
 	// random source: goroutine ticks
-	go tickFeeder()
+	module.StartServiceWorker("tick rng feeder", 0, tickFeeder)
 
 	// full feeder
-	go fullFeeder()
+	module.StartServiceWorker("full feeder", 0, fullFeeder)
 
 	return nil
 }

rng/rng_test.go

@@ -2,17 +2,10 @@ package rng
 
 import (
 	"testing"
-
-	"github.com/safing/portbase/config"
 )
 
 func init() {
-	err := prep()
-	if err != nil {
-		panic(err)
-	}
-
-	err = Start()
+	err := start()
 	if err != nil {
 		panic(err)
 	}
@@ -21,25 +14,17 @@ func init() {
 func TestRNG(t *testing.T) {
 	key := make([]byte, 16)
 
-	err := config.SetConfigOption("random/rng_cipher", "aes")
-	if err != nil {
-		t.Errorf("failed to set random/rng_cipher config: %s", err)
-	}
-	_, err = newCipher(key)
+	rngCipher = "aes"
+	_, err := newCipher(key)
 	if err != nil {
 		t.Errorf("failed to create aes cipher: %s", err)
 	}
-	rng.Reseed(key)
 
-	err = config.SetConfigOption("random/rng_cipher", "serpent")
-	if err != nil {
-		t.Errorf("failed to set random/rng_cipher config: %s", err)
-	}
+	rngCipher = "serpent"
 	_, err = newCipher(key)
 	if err != nil {
 		t.Errorf("failed to create serpent cipher: %s", err)
 	}
-	rng.Reseed(key)
 
 	b := make([]byte, 32)
 	_, err = Read(b)
@@ -55,4 +40,9 @@ func TestRNG(t *testing.T) {
 	if err != nil {
 		t.Errorf("Bytes failed: %s", err)
 	}
+
+	_, err = Number(100)
+	if err != nil {
+		t.Errorf("Number failed: %s", err)
+	}
 }

rng/tickfeeder.go

@@ -1,27 +1,25 @@
 package rng
 
 import (
+	"context"
+	"encoding/binary"
 	"time"
 )
 
-var (
-	tickDuration = 1 * time.Millisecond
-)
-
-func getTickDuration() time.Duration {
+func getTickFeederTickDuration() time.Duration {
 
 	// be ready in 1/10 time of reseedAfterSeconds
-	msecsAvailable := reseedAfterSeconds() * 100
-	// ex.: reseed after 10 minutes: msecsAvailable = 36000
+	msecsAvailable := reseedAfterSeconds * 100
+	// ex.: reseed after 10 minutes: msecsAvailable = 60000
 	// have full entropy after 5 minutes
 
 	// one tick generates 0,125 bits of entropy
-	ticksNeeded := minFeedEntropy() * 8
+	ticksNeeded := minFeedEntropy * 8
 	// ex.: minimum entropy is 256: ticksNeeded = 2048
 
 	// msces between ticks
 	tickMsecs := msecsAvailable / ticksNeeded
-	// ex.: tickMsecs = 17(,578125)
+	// ex.: tickMsecs = 29(,296875)
 
 	// use a minimum of 10 msecs per tick for good entropy
 	// it would take 21 seconds to get full 256 bits of entropy with 10msec ticks
@@ -29,33 +27,51 @@ func getTickDuration() time.Duration {
 		tickMsecs = 10
 	}
 
-	return time.Duration(tickMsecs * int64(time.Millisecond))
+	return time.Duration(tickMsecs) * time.Millisecond
 }
 
 // tickFeeder is a really simple entropy feeder that adds the least significant bit of the current nanosecond unixtime to its pool every time it 'ticks'.
 // The more work the program does, the better the quality, as the internal schedular cannot immediately run the goroutine when it's ready.
-func tickFeeder() {
+func tickFeeder(ctx context.Context) error {
 
 	var value int64
 	var pushes int
 	feeder := NewFeeder()
+	defer feeder.CloseFeeder()
+
+	tickDuration := getTickFeederTickDuration()
 
 	for {
-		select {
-		case <-time.After(tickDuration):
+		// wait for tick
+		time.Sleep(tickDuration)
 
-			value = (value << 1) | (time.Now().UnixNano() % 2)
+		// add tick value
+		value = (value << 1) | (time.Now().UnixNano() % 2)
+		pushes++
 
-			pushes++
-			if pushes >= 64 {
-				feeder.SupplyEntropyAsInt(value, 8)
-				pushes = 0
+		if pushes >= 64 {
+			// convert to []byte
+			b := make([]byte, 8)
+			binary.LittleEndian.PutUint64(b, uint64(value))
+			// reset
+			pushes = 0
+
+			// feed
+			select {
+			case feeder.input <- &entropyData{
+				data:    b,
+				entropy: 8,
+			}:
+			case <-ctx.Done():
+				return nil
+			}
+		} else {
+			// check if are done
+			select {
+			case <-ctx.Done():
+				return nil
+			default:
 			}
-
-			tickDuration = getTickDuration()
-
-		case <-shutdownSignal:
-			return
 		}
 	}
 }