Get rid of math/rand in favor of math/rand/v2

.golangci.yml

@@ -89,6 +89,8 @@ linters-settings:
         deny:
           - pkg: io/ioutil
             desc: 'use "io" or "os" packages instead'
+          - pkg: math/rand$
+            desc: 'use "math/rand/v2" or "crypto/rand" instead'
           - pkg: github.com/golang/protobuf
             desc: 'use "google.golang.org/protobuf"'
           - pkg: github.com/hashicorp/go-uuid

api/utils/retryutils/jitter.go

@@ -76,7 +76,7 @@ func FullJitter(d time.Duration) time.Duration {
 		return 0
 	}
 
-	return time.Duration(rand.Int64N(int64(d)))
+	return rand.N(d)
 }
 
 // HalfJitter is a jitter on the range [d/2, d). This is a large range and most
@@ -92,7 +92,7 @@ func HalfJitter(d time.Duration) time.Duration {
 		return d
 	}
 
-	return d - frac + time.Duration(rand.Int64N(int64(frac)))
+	return d - frac + rand.N(frac)
 }
 
 // SeventhJitter returns a jitter on the range [6d/7, d). Prefer smaller jitters
@@ -108,5 +108,5 @@ func SeventhJitter(d time.Duration) time.Duration {
 		return d
 	}
 
-	return d - frac + time.Duration(rand.Int64N(int64(frac)))
+	return d - frac + rand.N(frac)
 }

examples/dynamoathenamigration/migration_test.go

@@ -22,7 +22,7 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"math/rand"
+	"math/rand/v2"
 	"os"
 	"path/filepath"
 	"sort"
@@ -39,6 +39,7 @@ import (
 
 	apievents "github.com/gravitational/teleport/api/types/events"
 	"github.com/gravitational/teleport/api/utils/prompt"
+	"github.com/gravitational/teleport/api/utils/retryutils"
 	"github.com/gravitational/teleport/lib/utils"
 )
 
@@ -190,7 +191,7 @@ func (m *mockEmitter) EmitAuditEvent(ctx context.Context, in apievents.AuditEven
 	// Without it, in rare cases after 50 events still some worker were not able
 	// to read message because of other processing it immediately.
 	select {
-	case <-time.After(time.Duration(rand.Intn(50)+50) * time.Microsecond):
+	case <-time.After(retryutils.HalfJitter(100 * time.Microsecond)):
 		return nil
 	case <-ctx.Done():
 		return ctx.Err()
@@ -695,8 +696,6 @@ func generateExportFilesFromLines(t *testing.T, lines []string) (file *os.File,
 }
 
 func generateExportFileOfSize(t *testing.T, wantSize int, minDate, maxDate string) (*os.File, int) {
-	rnd := rand.New(rand.NewSource(time.Now().UnixNano()))
-
 	f, err := os.CreateTemp(t.TempDir(), "*")
 	require.NoError(t, err)
 	require.NoError(t, err)
@@ -705,7 +704,7 @@ func generateExportFileOfSize(t *testing.T, wantSize int, minDate, maxDate strin
 	var noOfEvents, size int
 	for size < wantSize {
 		noOfEvents++
-		line := eventLineFromTime(randomTime(t, minDate, maxDate, rnd).Format(time.DateOnly))
+		line := eventLineFromTime(randomTime(t, minDate, maxDate).Format(time.DateOnly))
 		size += len(line)
 		_, err = zw.Write([]byte(line + "\n"))
 		require.NoError(t, err)
@@ -717,16 +716,12 @@ func generateExportFileOfSize(t *testing.T, wantSize int, minDate, maxDate strin
 	return f, noOfEvents
 }
 
-func randomTime(t *testing.T, minStr, maxStr string, rnd *rand.Rand) time.Time {
+func randomTime(t *testing.T, minStr, maxStr string) time.Time {
 	min, err := time.Parse(time.DateOnly, minStr)
 	require.NoError(t, err)
 	max, err := time.Parse(time.DateOnly, maxStr)
 	require.NoError(t, err)
-	minUnix := min.Unix()
-	maxUnix := max.Unix()
-	delta := maxUnix - minUnix
-	sec := rnd.Int63n(delta) + minUnix
-	return time.Unix(sec, 0)
+	return min.Add(rand.N(max.Sub(min)))
 }
 
 func eventLineFromTime(eventTime string) string {

examples/teleport-usage/main.go

@@ -22,7 +22,7 @@ import (
 	"fmt"
 	"log"
 	"math"
-	"math/rand"
+	"math/rand/v2"
 	"os"
 	"reflect"
 	"strconv"
@@ -334,7 +334,7 @@ func (a *adaptiveRateLimiter) wait(permits float64) {
 	durationToWait := time.Duration(permits / a.permitCapacity * float64(time.Second))
 	time.Sleep(durationToWait)
 
-	if rand.Intn(10) == 0 {
+	if rand.N(10) == 0 {
 		a.adjustUp()
 	}
 }

integrations/lib/backoff/backoff.go

@@ -20,7 +20,7 @@ package backoff
 
 import (
 	"context"
-	"math/rand"
+	"math/rand/v2"
 	"time"
 
 	"github.com/gravitational/trace"
@@ -58,7 +58,7 @@ func NewDecorrWithMul(base, cap time.Duration, mul int64, clock clockwork.Clock)
 }
 
 func (backoff *decorr) Do(ctx context.Context) error {
-	backoff.sleep = backoff.base + rand.Int63n(backoff.sleep*backoff.mul-backoff.base)
+	backoff.sleep = backoff.base + rand.N(backoff.sleep*backoff.mul-backoff.base)
 	if backoff.sleep > backoff.cap {
 		backoff.sleep = backoff.cap
 	}

integrations/operator/controllers/resources/testlib/env.go

@@ -20,7 +20,7 @@ package testlib
 
 import (
 	"context"
-	"math/rand"
+	"math/rand/v2"
 	"os"
 	"path/filepath"
 	"runtime"
@@ -88,12 +88,11 @@ func deleteNamespaceForTest(t *testing.T, kc kclient.Client, ns *core.Namespace)
 	require.NoError(t, err)
 }
 
-var letterRunes = []rune("abcdefghijklmnopqrstuvwxyz1234567890")
-
 func ValidRandomResourceName(prefix string) string {
-	b := make([]rune, 5)
+	const letters = "abcdefghijklmnopqrstuvwxyz1234567890"
+	b := make([]byte, 5)
 	for i := range b {
-		b[i] = letterRunes[rand.Intn(len(letterRunes))]
+		b[i] = letters[rand.N(len(letters))]
 	}
 	return prefix + string(b)
 }

lib/auth/accountrecovery_test.go

@@ -23,7 +23,7 @@ import (
 	"encoding/binary"
 	"encoding/hex"
 	"fmt"
-	"math/rand"
+	"math/rand/v2"
 	"net/netip"
 	"strings"
 	"testing"

lib/auth/auth.go

@@ -38,7 +38,7 @@ import (
 	"io"
 	"log/slog"
 	"math/big"
-	insecurerand "math/rand"
+	mathrand "math/rand/v2"
 	"net"
 	"os"
 	"regexp"
@@ -1334,8 +1334,7 @@ func (a *Server) runPeriodicOperations() {
 	// to avoid contention on the database in case if there are multiple
 	// auth servers running - so they don't compete trying
 	// to update the same resources.
-	r := insecurerand.New(insecurerand.NewSource(a.GetClock().Now().UnixNano()))
-	period := defaults.HighResPollingPeriod + time.Duration(r.Intn(int(defaults.HighResPollingPeriod/time.Second)))*time.Second
+	period := retryutils.HalfJitter(2 * defaults.HighResPollingPeriod)
 
 	ticker := interval.NewMulti(
 		a.GetClock(),
@@ -1430,7 +1429,7 @@ func (a *Server) runPeriodicOperations() {
 			case <-a.closeCtx.Done():
 				return
 			case <-remoteClustersRefresh.Next():
-				a.refreshRemoteClusters(a.closeCtx, r)
+				a.refreshRemoteClusters(a.closeCtx)
 			}
 		}
 	}()
@@ -1859,7 +1858,7 @@ var (
 )
 
 // refreshRemoteClusters updates connection status of all remote clusters.
-func (a *Server) refreshRemoteClusters(ctx context.Context, rnd *insecurerand.Rand) {
+func (a *Server) refreshRemoteClusters(ctx context.Context) {
 	remoteClusters, err := a.Services.GetRemoteClusters(ctx)
 	if err != nil {
 		log.WithError(err).Error("Failed to load remote clusters for status refresh")
@@ -1873,7 +1872,7 @@ func (a *Server) refreshRemoteClusters(ctx context.Context, rnd *insecurerand.Ra
 	}
 
 	// randomize the order to optimize for multiple auth servers running in parallel
-	rnd.Shuffle(len(remoteClusters), func(i, j int) {
+	mathrand.Shuffle(len(remoteClusters), func(i, j int) {
 		remoteClusters[i], remoteClusters[j] = remoteClusters[j], remoteClusters[i]
 	})
 
@@ -4825,7 +4824,7 @@ func (a *Server) PingInventory(ctx context.Context, req proto.InventoryPingReque
 		return proto.InventoryPingResponse{}, trace.NotFound("no control stream found for server %q", req.ServerID)
 	}
 
-	id := insecurerand.Uint64()
+	id := mathrand.Uint64()
 
 	if !req.ControlLog {
 		// this ping doesn't pass through the control log, so just execute it immediately.

lib/auth/keystore/gcp_kms_test.go

@@ -25,7 +25,7 @@ import (
 	"crypto/x509/pkix"
 	"encoding/pem"
 	"math/big"
-	"math/rand"
+	mathrandv1 "math/rand" //nolint:depguard // only used for deterministic output
 	"net"
 	"strings"
 	"sync"
@@ -206,7 +206,7 @@ func (f *fakeGCPKMSServer) AsymmetricSign(ctx context.Context, req *kmspb.Asymme
 		return nil, trace.BadParameter("unsupported digest type %T", typedDigest)
 	}
 
-	testRand := rand.New(rand.NewSource(0))
+	testRand := mathrandv1.New(mathrandv1.NewSource(0))
 	sig, err := signer.Sign(testRand, digest, alg)
 	if err != nil {
 		return nil, trace.Wrap(err)
@@ -517,7 +517,7 @@ func TestGCPKMSKeystore(t *testing.T) {
 					Key:             clientPrivKey.SSHPublicKey(),
 					CertType:        ssh.HostCert,
 				}
-				err = cert.SignCert(rand.New(rand.NewSource(0)), sshSigner)
+				err = cert.SignCert(mathrandv1.New(mathrandv1.NewSource(0)), sshSigner)
 				if tc.expectSignError {
 					require.Error(t, err, "expected to get error signing SSH cert")
 					return
@@ -545,7 +545,7 @@ func TestGCPKMSKeystore(t *testing.T) {
 					},
 				}
 				_, err = x509.CreateCertificate(
-					rand.New(rand.NewSource(0)),
+					mathrandv1.New(mathrandv1.NewSource(0)),
 					template,
 					tlsCA.Cert,
 					clientPrivKey.Public(),

lib/auth/kube_test.go

@@ -19,10 +19,10 @@
 package auth
 
 import (
+	"crypto/rand"
 	"crypto/x509"
 	"crypto/x509/pkix"
 	"encoding/pem"
-	"math/rand"
 	"testing"
 	"time"
 
@@ -112,9 +112,7 @@ func newTestCSR(subj pkix.Name) ([]byte, error) {
 	x509CSR := &x509.CertificateRequest{
 		Subject: subj,
 	}
-	// Use math/rand to avoid blocking on system entropy.
-	rng := rand.New(rand.NewSource(0))
-	derCSR, err := x509.CreateCertificateRequest(rng, x509CSR, priv)
+	derCSR, err := x509.CreateCertificateRequest(rand.Reader, x509CSR, priv)
 	if err != nil {
 		return nil, err
 	}

lib/auth/password_test.go

@@ -22,7 +22,7 @@ import (
 	"context"
 	"encoding/base32"
 	"fmt"
-	"math/rand"
+	"math/rand/v2"
 	"testing"
 	"time"
 

lib/auth/trustedcluster_test.go

@@ -21,7 +21,6 @@ package auth
 import (
 	"context"
 	"fmt"
-	insecurerand "math/rand"
 	"testing"
 	"time"
 
@@ -44,7 +43,6 @@ import (
 func TestRemoteClusterStatus(t *testing.T) {
 	ctx := context.Background()
 	a := newTestAuthServer(ctx, t)
-	rnd := insecurerand.New(insecurerand.NewSource(a.GetClock().Now().UnixNano()))
 
 	rc, err := types.NewRemoteCluster("rc")
 	require.NoError(t, err)
@@ -53,7 +51,7 @@ func TestRemoteClusterStatus(t *testing.T) {
 
 	// This scenario deals with only one remote cluster, so it never hits the limit on status updates.
 	// TestRefreshRemoteClusters focuses on verifying the update limit logic.
-	a.refreshRemoteClusters(ctx, rnd)
+	a.refreshRemoteClusters(ctx)
 
 	wantRC := rc
 	// Initially, no tunnels exist and status should be "offline".
@@ -83,7 +81,7 @@ func TestRemoteClusterStatus(t *testing.T) {
 	require.NoError(t, err)
 	require.NoError(t, a.UpsertTunnelConnection(tc2))
 
-	a.refreshRemoteClusters(ctx, rnd)
+	a.refreshRemoteClusters(ctx)
 
 	// With active tunnels, the status is "online" and last_heartbeat is set to
 	// the latest tunnel heartbeat.
@@ -96,7 +94,7 @@ func TestRemoteClusterStatus(t *testing.T) {
 	// Delete the latest connection.
 	require.NoError(t, a.DeleteTunnelConnection(tc2.GetClusterName(), tc2.GetName()))
 
-	a.refreshRemoteClusters(ctx, rnd)
+	a.refreshRemoteClusters(ctx)
 
 	// The status should remain the same, since tc1 still exists.
 	// The last_heartbeat should remain the same, since tc1 has an older
@@ -109,7 +107,7 @@ func TestRemoteClusterStatus(t *testing.T) {
 	// Delete the remaining connection
 	require.NoError(t, a.DeleteTunnelConnection(tc1.GetClusterName(), tc1.GetName()))
 
-	a.refreshRemoteClusters(ctx, rnd)
+	a.refreshRemoteClusters(ctx)
 
 	// The status should switch to "offline".
 	// The last_heartbeat should remain the same.
@@ -162,7 +160,6 @@ func TestRefreshRemoteClusters(t *testing.T) {
 			require.LessOrEqual(t, tt.clustersNeedUpdate, tt.clustersTotal)
 
 			a := newTestAuthServer(ctx, t)
-			rnd := insecurerand.New(insecurerand.NewSource(a.GetClock().Now().UnixNano()))
 
 			allClusters := make(map[string]types.RemoteCluster)
 			for i := 0; i < tt.clustersTotal; i++ {
@@ -186,7 +183,7 @@ func TestRefreshRemoteClusters(t *testing.T) {
 				}
 			}
 
-			a.refreshRemoteClusters(ctx, rnd)
+			a.refreshRemoteClusters(ctx)
 
 			clusters, err := a.GetRemoteClusters(ctx)
 			require.NoError(t, err)

lib/auth/usertoken_test.go

@@ -22,7 +22,7 @@ import (
 	"context"
 	"encoding/base32"
 	"fmt"
-	"math/rand"
+	"math/rand/v2"
 	"testing"
 	"time"
 

lib/benchmark/ssh.go

@@ -20,7 +20,7 @@ package benchmark
 
 import (
 	"context"
-	"math/rand"
+	"math/rand/v2"
 
 	"github.com/gravitational/trace"
 
@@ -81,7 +81,7 @@ func chooseRandomHost(hosts []types.Server) string {
 		name := hosts[0].GetName()
 		return name + ":0"
 	default:
-		name := hosts[rand.Intn(len(hosts))].GetName()
+		name := hosts[rand.N(len(hosts))].GetName()
 		return name + ":0"
 	}
 }