Ttx/replace random nonce (#1406)

Signed-off-by: Siddhi Khandelwal <siddhi.200727@gmail.com>

Author: sid200727

go.mod

@@ -13,6 +13,7 @@ require (
 	github.com/gin-gonic/gin v1.11.0
 	github.com/go-co-op/gocron/v2 v2.19.1
 	github.com/google/pprof v0.0.0-20260202012954-cb029daf43ef
+	github.com/google/uuid v1.6.0
 	github.com/hashicorp/go-uuid v1.0.3
 	github.com/hyperledger-labs/fabric-smart-client v0.8.3-0.20260302105910-adde99d4bf54
 	github.com/hyperledger/fabric-chaincode-go/v2 v2.3.0
@@ -122,7 +123,6 @@ require (
 	github.com/google/go-cmp v0.7.0 // indirect
 	github.com/google/gopacket v1.1.19 // indirect
 	github.com/google/s2a-go v0.1.8 // indirect
-	github.com/google/uuid v1.6.0 // indirect
 	github.com/googleapis/enterprise-certificate-proxy v0.3.4 // indirect
 	github.com/googleapis/gax-go/v2 v2.14.1 // indirect
 	github.com/gorilla/mux v1.8.1 // indirect

token/services/ttx/random.go

@@ -8,6 +8,7 @@ package ttx
 
 import (
 	"crypto/rand"
+	"io"
 
 	"github.com/hyperledger-labs/fabric-smart-client/pkg/utils/errors"
 )
@@ -17,12 +18,12 @@ const (
 	NonceSize = 24
 )
 
-// GetRandomBytes returns len random looking bytes
-func GetRandomBytes(len int) ([]byte, error) {
-	key := make([]byte, len)
+// GetRandomBytes returns length random bytes, guaranteeing the buffer is fully filled
+func GetRandomBytes(length int) ([]byte, error) {
+	key := make([]byte, length)
 
-	// TODO: rand could fill less bytes then len
-	_, err := rand.Read(key)
+	// Ensure the buffer is completely filled
+	_, err := io.ReadFull(rand.Reader, key)
 	if err != nil {
 		return nil, errors.Wrap(err, "error getting random bytes")
 	}