Uncompress gzip data in tx body

x/wasm/internal/keeper/ioutil.go

@@ -0,0 +1,38 @@
+package keeper
+
+import (
+	"bytes"
+	"compress/gzip"
+	"io"
+	"io/ioutil"
+)
+
+// magic bytes to identify gzip.
+// See https://www.ietf.org/rfc/rfc1952.txt
+// and https://github.com/golang/go/blob/master/src/net/http/sniff.go#L186
+var gzipIdent = []byte("\x1F\x8B\x08")
+
+// limit max bytes read to prevent gzip bombs
+const maxSize = 400 * 1024
+
+// uncompress returns gzip uncompressed content or given src when not gzip.
+func uncompress(src []byte) ([]byte, error) {
+	if len(src) < 3 {
+		return src, nil
+	}
+	in := io.LimitReader(bytes.NewReader(src), maxSize)
+	buf := make([]byte, 3)
+	if _, err := io.ReadAtLeast(in, buf, 3); err != nil {
+		return nil, err
+	}
+	if !bytes.Equal(gzipIdent, buf) {
+		return src, nil
+	}
+	zr, err := gzip.NewReader(io.MultiReader(bytes.NewReader(buf), in))
+	if err != nil {
+		return nil, err
+	}
+	zr.Multistream(false)
+
+	return ioutil.ReadAll(zr)
+}

x/wasm/internal/keeper/ioutil_test.go

@@ -0,0 +1,63 @@
+package keeper
+
+import (
+	"errors"
+	"io"
+	"io/ioutil"
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestUncompress(t *testing.T) {
+	wasmRaw, err := ioutil.ReadFile("./testdata/contract.wasm")
+	require.NoError(t, err)
+
+	wasmGzipped, err := ioutil.ReadFile("./testdata/contract.wasm.gzip")
+	require.NoError(t, err)
+
+	specs := map[string]struct {
+		src       []byte
+		expError  error
+		expResult []byte
+	}{
+		"handle wasm uncompressed": {
+			src:       wasmRaw,
+			expResult: wasmRaw,
+		},
+		"handle wasm compressed": {
+			src:       wasmGzipped,
+			expResult: wasmRaw,
+		},
+		"handle nil slice": {
+			src:       nil,
+			expResult: nil,
+		},
+		"handle short unidentified": {
+			src:       []byte{0x1, 0x2},
+			expResult: []byte{0x1, 0x2},
+		},
+		"handle big slice": {
+			src:       []byte(strings.Repeat("a", maxSize+1)),
+			expResult: []byte(strings.Repeat("a", maxSize+1)),
+		},
+		"handle gzip identifier only": {
+			src:      gzipIdent,
+			expError: io.ErrUnexpectedEOF,
+		},
+		"handle broken gzip": {
+			src:      append(gzipIdent, byte(0x1)),
+			expError: io.ErrUnexpectedEOF,
+		},
+	}
+	for msg, spec := range specs {
+		t.Run(msg, func(t *testing.T) {
+			r, err := uncompress(spec.src)
+			require.True(t, errors.Is(spec.expError, err), "exp %+v got %+v", spec.expError, err)
+			assert.Equal(t, spec.expResult, r)
+		})
+	}
+
+}

x/wasm/internal/keeper/keeper.go

@@ -58,6 +58,10 @@ func NewKeeper(cdc *codec.Codec, storeKey sdk.StoreKey, accountKeeper auth.Accou
 
 // Create uploads and compiles a WASM contract, returning a short identifier for the contract
 func (k Keeper) Create(ctx sdk.Context, creator sdk.AccAddress, wasmCode []byte) (codeID uint64, sdkErr sdk.Error) {
+	wasmCode, err := uncompress(wasmCode)
+	if err != nil {
+		return 0, types.ErrCreateFailed(err)
+	}
 	codeHash, err := k.wasmer.Create(wasmCode)
 	if err != nil {
 		return 0, types.ErrCreateFailed(err)

x/wasm/internal/keeper/keeper_test.go

@@ -39,6 +39,33 @@ func TestCreate(t *testing.T) {
 	contractID, err := keeper.Create(ctx, creator, wasmCode)
 	require.NoError(t, err)
 	require.Equal(t, uint64(1), contractID)
+	// and verify content
+	storedCode, err := keeper.GetByteCode(ctx, contractID)
+	require.NoError(t, err)
+	require.Equal(t, wasmCode, storedCode)
+}
+
+func TestCreateWithGzippedPayload(t *testing.T) {
+	tempDir, err := ioutil.TempDir("", "wasm")
+	require.NoError(t, err)
+	defer os.RemoveAll(tempDir)
+	ctx, accKeeper, keeper := CreateTestInput(t, false, tempDir)
+
+	deposit := sdk.NewCoins(sdk.NewInt64Coin("denom", 100000))
+	creator := createFakeFundedAccount(ctx, accKeeper, deposit)
+
+	wasmCode, err := ioutil.ReadFile("./testdata/contract.wasm.gzip")
+	require.NoError(t, err)
+
+	contractID, err := keeper.Create(ctx, creator, wasmCode)
+	require.NoError(t, err)
+	require.Equal(t, uint64(1), contractID)
+	// and verify content
+	storedCode, err := keeper.GetByteCode(ctx, contractID)
+	require.NoError(t, err)
+	rawCode, err := ioutil.ReadFile("./testdata/contract.wasm")
+	require.NoError(t, err)
+	require.Equal(t, rawCode, storedCode)
 }
 
 func TestInstantiate(t *testing.T) {