Upgrade cadence and change to ReadRandom

fvm/environment/facade_env.go

@@ -315,9 +315,3 @@ func (env *facadeEnvironment) SetInterpreterSharedState(state *interpreter.Share
 func (env *facadeEnvironment) GetInterpreterSharedState() *interpreter.SharedState {
 	return nil
 }
-
-func (env *facadeEnvironment) ReadRandom(buffer []byte) error {
-	// NO-OP for now, to unblock certain downstream dependencies.
-	// E.g. cadence-tools/test
-	return nil
-}

fvm/environment/random_generator.go

@@ -1,7 +1,6 @@
 package environment
 
 import (
-	"encoding/binary"
 	"fmt"
 
 	"github.com/onflow/flow-go/crypto/random"
@@ -23,9 +22,9 @@ type EntropyProvider interface {
 }
 
 type RandomGenerator interface {
-	// UnsafeRandom returns a random uint64
+	// ReadRandom reads pseudo-random bytes into the input slice, using distributed randomness.
 	// The name follows Cadence interface
-	UnsafeRandom() (uint64, error)
+	ReadRandom([]byte) error
 }
 
 var _ RandomGenerator = (*randomGenerator)(nil)
@@ -55,14 +54,12 @@ func NewParseRestrictedRandomGenerator(
 	}
 }
 
-func (gen ParseRestrictedRandomGenerator) UnsafeRandom() (
-	uint64,
-	error,
-) {
-	return parseRestrict1Ret(
+func (gen ParseRestrictedRandomGenerator) ReadRandom(buf []byte) error {
+	return parseRestrict1Arg(
 		gen.txnState,
 		trace.FVMEnvRandom,
-		gen.impl.UnsafeRandom)
+		gen.impl.ReadRandom,
+		buf)
 }
 
 func NewRandomGenerator(
@@ -104,28 +101,27 @@ func (gen *randomGenerator) createPRG() (random.Rand, error) {
 	return csprg, nil
 }
 
-// UnsafeRandom returns a random uint64 using the underlying PRG (currently
+// ReadRandom reads pseudo-random bytes into the input slice using the underlying PRG (currently
 // using a crypto-secure one). This function is not thread safe, due to the gen.prg
 // instance currently used. This is fine because a
 // single transaction has a single RandomGenerator and is run in a single
 // thread.
-func (gen *randomGenerator) UnsafeRandom() (uint64, error) {
+func (gen *randomGenerator) ReadRandom(buf []byte) error {
 	defer gen.tracer.StartExtensiveTracingChildSpan(
 		trace.FVMEnvRandom).End()
 
 	// PRG creation is only done once.
 	if !gen.isPRGCreated {
 		newPRG, err := gen.createPRG()
 		if err != nil {
-			return 0, err
+			return err
 		}
 		gen.prg = newPRG
 		gen.isPRGCreated = true
 	}
 
-	buf := make([]byte, 8)
-	gen.prg.Read(buf) // Note: prg.Read does not return error
-	return binary.LittleEndian.Uint64(buf), nil
+	gen.prg.Read(buf)
+	return nil
 }
 
 var _ RandomGenerator = (*dummyRandomGenerator)(nil)
@@ -138,8 +134,7 @@ func NewDummyRandomGenerator() RandomGenerator {
 	return &dummyRandomGenerator{}
 }
 
-// UnsafeRandom() returns an error because executing scripts
-// does not support randomness APIs.
-func (gen *dummyRandomGenerator) UnsafeRandom() (uint64, error) {
-	return 0, nil
+// ReadRandom does nothing, because scripts do not support randomness APIs.
+func (gen *dummyRandomGenerator) ReadRandom(buf []byte) error {
+	return nil
 }

fvm/environment/random_generator_test.go

@@ -1,6 +1,7 @@
 package environment_test
 
 import (
+	"encoding/binary"
 	"math"
 	mrand "math/rand"
 	"testing"
@@ -27,9 +28,10 @@ func TestRandomGenerator(t *testing.T) {
 			txId)
 		numbers := make([]uint64, N)
 		for i := 0; i < N; i++ {
-			u, err := urg.UnsafeRandom()
+			var buffer [8]byte
+			err := urg.ReadRandom(buffer[:])
 			require.NoError(t, err)
-			numbers[i] = u
+			numbers[i] = binary.LittleEndian.Uint64(buffer[:])
 		}
 		return numbers
 	}
@@ -48,7 +50,14 @@ func TestRandomGenerator(t *testing.T) {
 			// n is a random power of 2 (from 2 to 2^10)
 			n := 1 << (1 + mrand.Intn(10))
 			classWidth := (math.MaxUint64 / uint64(n)) + 1
-			random.BasicDistributionTest(t, uint64(n), uint64(classWidth), urg.UnsafeRandom)
+			random.BasicDistributionTest(t, uint64(n), uint64(classWidth), func() (uint64, error) {
+				var buffer [8]byte
+				err := urg.ReadRandom(buffer[:])
+				if err != nil {
+					return 0, err
+				}
+				return binary.LittleEndian.Uint64(buffer[:]), nil
+			})
 		}
 	})
 

go.mod

@@ -51,7 +51,7 @@ require (
 	github.com/multiformats/go-multiaddr-dns v0.3.1
 	github.com/multiformats/go-multihash v0.2.3
 	github.com/onflow/atree v0.6.0
-	github.com/onflow/cadence v0.40.0
+	github.com/onflow/cadence v0.40.1-0.20230830181337-52549529e96b
 	github.com/onflow/flow v0.3.4
 	github.com/onflow/flow-core-contracts/lib/go/contracts v1.2.4-0.20230703193002-53362441b57d
 	github.com/onflow/flow-core-contracts/lib/go/templates v1.2.3

go.sum

@@ -1240,8 +1240,8 @@ github.com/onflow/atree v0.1.0-beta1.0.20211027184039-559ee654ece9/go.mod h1:+6x
 github.com/onflow/atree v0.6.0 h1:j7nQ2r8npznx4NX39zPpBYHmdy45f4xwoi+dm37Jk7c=
 github.com/onflow/atree v0.6.0/go.mod h1:gBHU0M05qCbv9NN0kijLWMgC47gHVNBIp4KmsVFi0tc=
 github.com/onflow/cadence v0.20.1/go.mod h1:7mzUvPZUIJztIbr9eTvs+fQjWWHTF8veC+yk4ihcNIA=
-github.com/onflow/cadence v0.40.0 h1:3pTdkyVTjMx2U5+YZYvIpyw74CSxabjk9PdAZUkJ1GU=
-github.com/onflow/cadence v0.40.0/go.mod h1:OIJLyVBPa339DCBQXBfGaorT4tBjQh9gSKe+ZAIyyh0=
+github.com/onflow/cadence v0.40.1-0.20230830181337-52549529e96b h1:n9/WMBooqLRXERLYMCa/23qrULdyfBvio2OlGTuo/iM=
+github.com/onflow/cadence v0.40.1-0.20230830181337-52549529e96b/go.mod h1:2ggmhENvPPZXRnv9SmqN2xiYvluu4wx/96GCpeRh8lU=
 github.com/onflow/flow v0.3.4 h1:FXUWVdYB90f/rjNcY0Owo30gL790tiYff9Pb/sycXYE=
 github.com/onflow/flow v0.3.4/go.mod h1:lzyAYmbu1HfkZ9cfnL5/sjrrsnJiUU8fRL26CqLP7+c=
 github.com/onflow/flow-core-contracts/lib/go/contracts v1.2.4-0.20230703193002-53362441b57d h1:B7PdhdUNkve5MVrekWDuQf84XsGBxNZ/D3x+QQ8XeVs=

insecure/go.mod

@@ -180,7 +180,7 @@ require (
 	github.com/multiformats/go-multistream v0.4.1 // indirect
 	github.com/multiformats/go-varint v0.0.7 // indirect
 	github.com/onflow/atree v0.6.0 // indirect
-	github.com/onflow/cadence v0.40.0 // indirect
+	github.com/onflow/cadence v0.40.1-0.20230830181337-52549529e96b // indirect
 	github.com/onflow/flow-core-contracts/lib/go/contracts v1.2.4-0.20230703193002-53362441b57d // indirect
 	github.com/onflow/flow-core-contracts/lib/go/templates v1.2.3 // indirect
 	github.com/onflow/flow-ft/lib/go/contracts v0.7.0 // indirect

insecure/go.sum

@@ -1216,8 +1216,8 @@ github.com/onflow/atree v0.1.0-beta1.0.20211027184039-559ee654ece9/go.mod h1:+6x
 github.com/onflow/atree v0.6.0 h1:j7nQ2r8npznx4NX39zPpBYHmdy45f4xwoi+dm37Jk7c=
 github.com/onflow/atree v0.6.0/go.mod h1:gBHU0M05qCbv9NN0kijLWMgC47gHVNBIp4KmsVFi0tc=
 github.com/onflow/cadence v0.20.1/go.mod h1:7mzUvPZUIJztIbr9eTvs+fQjWWHTF8veC+yk4ihcNIA=
-github.com/onflow/cadence v0.40.0 h1:3pTdkyVTjMx2U5+YZYvIpyw74CSxabjk9PdAZUkJ1GU=
-github.com/onflow/cadence v0.40.0/go.mod h1:OIJLyVBPa339DCBQXBfGaorT4tBjQh9gSKe+ZAIyyh0=
+github.com/onflow/cadence v0.40.1-0.20230830181337-52549529e96b h1:n9/WMBooqLRXERLYMCa/23qrULdyfBvio2OlGTuo/iM=
+github.com/onflow/cadence v0.40.1-0.20230830181337-52549529e96b/go.mod h1:2ggmhENvPPZXRnv9SmqN2xiYvluu4wx/96GCpeRh8lU=
 github.com/onflow/flow-core-contracts/lib/go/contracts v1.2.4-0.20230703193002-53362441b57d h1:B7PdhdUNkve5MVrekWDuQf84XsGBxNZ/D3x+QQ8XeVs=
 github.com/onflow/flow-core-contracts/lib/go/contracts v1.2.4-0.20230703193002-53362441b57d/go.mod h1:xAiV/7TKhw863r6iO3CS5RnQ4F+pBY1TxD272BsILlo=
 github.com/onflow/flow-core-contracts/lib/go/templates v1.2.3 h1:X25A1dNajNUtE+KoV76wQ6BR6qI7G65vuuRXxDDqX7E=

integration/go.mod

@@ -17,7 +17,7 @@ require (
 	github.com/ipfs/go-datastore v0.6.0
 	github.com/ipfs/go-ds-badger2 v0.1.3
 	github.com/ipfs/go-ipfs-blockstore v1.3.0
-	github.com/onflow/cadence v0.40.0
+	github.com/onflow/cadence v0.40.1-0.20230830181337-52549529e96b
 	github.com/onflow/flow-core-contracts/lib/go/contracts v1.2.4-0.20230703193002-53362441b57d
 	github.com/onflow/flow-core-contracts/lib/go/templates v1.2.3
 	github.com/onflow/flow-emulator v0.53.0

integration/go.sum

@@ -1354,8 +1354,8 @@ github.com/onflow/atree v0.1.0-beta1.0.20211027184039-559ee654ece9/go.mod h1:+6x
 github.com/onflow/atree v0.6.0 h1:j7nQ2r8npznx4NX39zPpBYHmdy45f4xwoi+dm37Jk7c=
 github.com/onflow/atree v0.6.0/go.mod h1:gBHU0M05qCbv9NN0kijLWMgC47gHVNBIp4KmsVFi0tc=
 github.com/onflow/cadence v0.20.1/go.mod h1:7mzUvPZUIJztIbr9eTvs+fQjWWHTF8veC+yk4ihcNIA=
-github.com/onflow/cadence v0.40.0 h1:3pTdkyVTjMx2U5+YZYvIpyw74CSxabjk9PdAZUkJ1GU=
-github.com/onflow/cadence v0.40.0/go.mod h1:OIJLyVBPa339DCBQXBfGaorT4tBjQh9gSKe+ZAIyyh0=
+github.com/onflow/cadence v0.40.1-0.20230830181337-52549529e96b h1:n9/WMBooqLRXERLYMCa/23qrULdyfBvio2OlGTuo/iM=
+github.com/onflow/cadence v0.40.1-0.20230830181337-52549529e96b/go.mod h1:2ggmhENvPPZXRnv9SmqN2xiYvluu4wx/96GCpeRh8lU=
 github.com/onflow/flow-core-contracts/lib/go/contracts v1.2.4-0.20230703193002-53362441b57d h1:B7PdhdUNkve5MVrekWDuQf84XsGBxNZ/D3x+QQ8XeVs=
 github.com/onflow/flow-core-contracts/lib/go/contracts v1.2.4-0.20230703193002-53362441b57d/go.mod h1:xAiV/7TKhw863r6iO3CS5RnQ4F+pBY1TxD272BsILlo=
 github.com/onflow/flow-core-contracts/lib/go/templates v1.2.3 h1:X25A1dNajNUtE+KoV76wQ6BR6qI7G65vuuRXxDDqX7E=