Problem: no max length validation for blob msg

CHANGELOG.md

@@ -10,6 +10,7 @@
 * [#1610](https://github.com/crypto-org-chain/cronos/pull/1610) Sync e2ee module with v1.3.x branch.
 * [#1612](https://github.com/crypto-org-chain/cronos/pull/1612) Support ibc channel upgrade related methods.
 * [#1614](https://github.com/crypto-org-chain/cronos/pull/1614) Bump cosmos-sdk to v0.50.10.
+* [#1613](https://github.com/crypto-org-chain/cronos/pull/1613) Add max length validation for blob msg.
 
 ### Bug Fixes
 

x/cronos/types/messages.go

@@ -335,18 +335,25 @@ func NewMsgStoreBlockList(from string, blob []byte) *MsgStoreBlockList {
 
 var errDummyIdentity = stderrors.New("dummy")
 
+const MaximumBlobLength = 20480
+
 type dummyIdentity struct{}
 
 func (i *dummyIdentity) Unwrap(stanzas []*age.Stanza) ([]byte, error) {
 	return nil, errDummyIdentity
 }
 
 func (msg *MsgStoreBlockList) ValidateBasic() error {
+	length := len(msg.Blob)
+	if length > MaximumBlobLength {
+		return errors.Wrapf(sdkerrors.ErrInvalidRequest, "block length %d must not exceed %d", length, MaximumBlobLength)
+	}
 	_, err := sdk.AccAddressFromBech32(msg.From)
 	if err != nil {
 		return errors.Wrapf(sdkerrors.ErrInvalidAddress, "invalid sender address (%s)", err)
 	}
-
+	// skip heavy operation in Decrypt by early return with errDummyIdentity in
+	// https://github.com/FiloSottile/age/blob/v1.1.1/age.go#L197
 	_, err = age.Decrypt(bytes.NewBuffer(msg.Blob), new(dummyIdentity))
 	if err != nil && err != errDummyIdentity {
 		return err

x/cronos/types/messages_test.go

@@ -1,16 +1,20 @@
 package types_test
 
 import (
+	"bytes"
 	"fmt"
+	"log"
 	"testing"
 
-	"github.com/crypto-org-chain/cronos/v2/app"
+	"filippo.io/age"
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	cmdcfg "github.com/crypto-org-chain/cronos/v2/cmd/cronosd/config"
 	"github.com/crypto-org-chain/cronos/v2/x/cronos/types"
 	"github.com/stretchr/testify/require"
 )
 
 func TestValidateMsgUpdateTokenMapping(t *testing.T) {
-	app.SetConfig()
+	cmdcfg.SetBech32Prefixes(sdk.GetConfig())
 
 	testCases := []struct {
 		name     string
@@ -54,3 +58,78 @@ func TestValidateMsgUpdateTokenMapping(t *testing.T) {
 		})
 	}
 }
+
+func TestValidateMsgStoreBlockList(t *testing.T) {
+	cmdcfg.SetBech32Prefixes(sdk.GetConfig())
+
+	publicKey := "age1cy0su9fwf3gf9mw868g5yut09p6nytfmmnktexz2ya5uqg9vl9sss4euqm"
+	recipient, err := age.ParseX25519Recipient(publicKey)
+	if err != nil {
+		log.Fatalf("Failed to parse public key %q: %v", publicKey, err)
+	}
+
+	from := "crc12luku6uxehhak02py4rcz65zu0swh7wjsrw0pp"
+	blob := []byte("valid blob data")
+	testCases := []struct {
+		name        string
+		msg         *types.MsgStoreBlockList
+		noEncrypt   bool
+		expectError bool
+		errorMsg    string
+	}{
+		{
+			"valid message",
+			types.NewMsgStoreBlockList(from, blob),
+			false,
+			false,
+			"",
+		},
+		{
+			"blob exceeds maximum length",
+			types.NewMsgStoreBlockList(
+				from,
+				make([]byte, types.MaximumBlobLength+1),
+			),
+			false,
+			true,
+			fmt.Sprintf("must not exceed %d", types.MaximumBlobLength),
+		},
+		{
+			"invalid sender address",
+			types.NewMsgStoreBlockList("invalid", blob),
+			false,
+			true,
+			"invalid sender address",
+		},
+		{
+			"decryption error",
+			types.NewMsgStoreBlockList(from, blob),
+			true,
+			true,
+			"failed to read header",
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			if !tc.noEncrypt {
+				out := new(bytes.Buffer)
+				w, err := age.Encrypt(out, recipient)
+				require.NoError(t, err)
+				_, err = w.Write(tc.msg.Blob)
+				require.NoError(t, err)
+				err = w.Close()
+				require.NoError(t, err)
+				tc.msg.Blob = out.Bytes()
+			}
+
+			err = tc.msg.ValidateBasic()
+			if tc.expectError {
+				require.Error(t, err)
+				require.Contains(t, err.Error(), tc.errorMsg)
+			} else {
+				require.NoError(t, err)
+			}
+		})
+	}
+}