From 41279aa13a9bab53d65e2a2693512e986d8024cc Mon Sep 17 00:00:00 2001
From: dusan-ethernal <dusan.maksimovic@ethernal.tech>
Date: Mon, 15 Aug 2022 12:01:35 +0200
Subject: [PATCH] Fix for issue #115: Disable messages on consumer chain

---
 app/consumer/ante/disabled_modules_ante.go    | 31 ++++++++
 .../ante/disabled_modules_ante_test.go        | 78 +++++++++++++++++++
 app/consumer/ante_handler.go                  |  1 +
 3 files changed, 110 insertions(+)
 create mode 100644 app/consumer/ante/disabled_modules_ante.go
 create mode 100644 app/consumer/ante/disabled_modules_ante_test.go

diff --git a/app/consumer/ante/disabled_modules_ante.go b/app/consumer/ante/disabled_modules_ante.go
new file mode 100644
index 0000000000..fdbe932f37
--- /dev/null
+++ b/app/consumer/ante/disabled_modules_ante.go
@@ -0,0 +1,31 @@
+package ante
+
+import (
+	"fmt"
+	"strings"
+
+	sdk "github.com/cosmos/cosmos-sdk/types"
+)
+
+type DisabledModulesDecorator struct {
+	prefixes []string
+}
+
+func NewDisabledModulesDecorator(disabledModules ...string) DisabledModulesDecorator {
+	return DisabledModulesDecorator{prefixes: disabledModules}
+}
+
+func (dmd DisabledModulesDecorator) AnteHandle(ctx sdk.Context, tx sdk.Tx, simulate bool, next sdk.AnteHandler) (newCtx sdk.Context, err error) {
+	currHeight := ctx.BlockHeight()
+	for _, msg := range tx.GetMsgs() {
+		msgTypeURL := sdk.MsgTypeURL(msg)
+
+		for _, prefix := range dmd.prefixes {
+			if strings.HasPrefix(msgTypeURL, prefix) {
+				return ctx, fmt.Errorf("tx contains message types from unsupported modules at height %d", currHeight)
+			}
+		}
+	}
+
+	return next(ctx, tx, simulate)
+}
diff --git a/app/consumer/ante/disabled_modules_ante_test.go b/app/consumer/ante/disabled_modules_ante_test.go
new file mode 100644
index 0000000000..08dfc23bb3
--- /dev/null
+++ b/app/consumer/ante/disabled_modules_ante_test.go
@@ -0,0 +1,78 @@
+package ante_test
+
+import (
+	"testing"
+
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	banktypes "github.com/cosmos/cosmos-sdk/x/bank/types"
+	evidencetypes "github.com/cosmos/cosmos-sdk/x/evidence/types"
+	slashingtypes "github.com/cosmos/cosmos-sdk/x/slashing/types"
+	ibcclienttypes "github.com/cosmos/ibc-go/v3/modules/core/02-client/types"
+	appconsumer "github.com/cosmos/interchain-security/app/consumer"
+	"github.com/cosmos/interchain-security/app/consumer/ante"
+	"github.com/stretchr/testify/require"
+	"github.com/tendermint/spm/cosmoscmd"
+)
+
+func TestDisabledModulesDecorator(t *testing.T) {
+	txCfg := cosmoscmd.MakeEncodingConfig(appconsumer.ModuleBasics).TxConfig
+
+	testCases := []struct {
+		name      string
+		ctx       sdk.Context
+		msgs      []sdk.Msg
+		expectErr bool
+	}{
+		{
+			name: "IBC module messages supported",
+			ctx:  sdk.Context{},
+			msgs: []sdk.Msg{
+				&ibcclienttypes.MsgUpdateClient{},
+			},
+			expectErr: false,
+		},
+		{
+			name: "bank module messages supported",
+			ctx:  sdk.Context{},
+			msgs: []sdk.Msg{
+				&banktypes.MsgSend{},
+			},
+			expectErr: false,
+		},
+		{
+			name: "evidence module messages not supported",
+			ctx:  sdk.Context{},
+			msgs: []sdk.Msg{
+				&evidencetypes.MsgSubmitEvidence{},
+			},
+			expectErr: true,
+		},
+		{
+			name: "slashing module messages not supported",
+			ctx:  sdk.Context{},
+			msgs: []sdk.Msg{
+				&slashingtypes.MsgUnjail{},
+			},
+			expectErr: true,
+		},
+	}
+
+	for _, tc := range testCases {
+		tc := tc
+
+		t.Run(tc.name, func(t *testing.T) {
+			handler := ante.NewDisabledModulesDecorator("/cosmos.evidence", "/cosmos.slashing")
+
+			txBuilder := txCfg.NewTxBuilder()
+			require.NoError(t, txBuilder.SetMsgs(tc.msgs...))
+
+			_, err := handler.AnteHandle(tc.ctx, txBuilder.GetTx(), false,
+				func(ctx sdk.Context, _ sdk.Tx, _ bool) (sdk.Context, error) { return ctx, nil })
+			if tc.expectErr {
+				require.Error(t, err)
+			} else {
+				require.NoError(t, err)
+			}
+		})
+	}
+}
diff --git a/app/consumer/ante_handler.go b/app/consumer/ante_handler.go
index ea0984b41b..5e282ae06a 100644
--- a/app/consumer/ante_handler.go
+++ b/app/consumer/ante_handler.go
@@ -39,6 +39,7 @@ func NewAnteHandler(options HandlerOptions) (sdk.AnteHandler, error) {
 		ante.NewSetUpContextDecorator(),
 		ante.NewRejectExtensionOptionsDecorator(),
 		consumerante.NewMsgFilterDecorator(options.ConsumerKeeper),
+		consumerante.NewDisabledModulesDecorator("/cosmos.evidence", "/cosmos.slashing"),
 		ante.NewMempoolFeeDecorator(),
 		ante.NewValidateBasicDecorator(),
 		ante.NewTxTimeoutHeightDecorator(),