diff --git a/accounts/abi/argument.go b/accounts/abi/argument.go index 93b513c346..f544c80dbb 100644 --- a/accounts/abi/argument.go +++ b/accounts/abi/argument.go @@ -243,11 +243,7 @@ func (arguments Arguments) Pack(args ...interface{}) ([]byte, error) { // input offset is the bytes offset for packed output inputOffset := 0 for _, abiArg := range abiArgs { - if abiArg.Type.T == ArrayTy { - inputOffset += 32 * abiArg.Type.Size - } else { - inputOffset += 32 - } + inputOffset += getDynamicTypeOffset(abiArg.Type) } var ret []byte for i, a := range args { @@ -257,14 +253,13 @@ func (arguments Arguments) Pack(args ...interface{}) ([]byte, error) { if err != nil { return nil, err } - // check for a slice type (string, bytes, slice) - if input.Type.requiresLengthPrefix() { - // calculate the offset - offset := inputOffset + len(variableInput) + // check for dynamic types + if isDynamicType(input.Type) { // set the offset - ret = append(ret, packNum(reflect.ValueOf(offset))...) - // Append the packed output to the variable input. The variable input - // will be appended at the end of the input. + ret = append(ret, packNum(reflect.ValueOf(inputOffset))...) + // calculate next offset + inputOffset += len(packed) + // append to variable input variableInput = append(variableInput, packed...) } else { // append the packed value to the input diff --git a/accounts/abi/pack_test.go b/accounts/abi/pack_test.go index 58a5b7a581..ddd2b7362d 100644 --- a/accounts/abi/pack_test.go +++ b/accounts/abi/pack_test.go @@ -324,6 +324,66 @@ func TestPack(t *testing.T) { "foobar", common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000006666f6f6261720000000000000000000000000000000000000000000000000000"), }, + { + "string[]", + []string{"hello", "foobar"}, + common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000002" + // len(array) = 2 + "0000000000000000000000000000000000000000000000000000000000000040" + // offset 64 to i = 0 + "0000000000000000000000000000000000000000000000000000000000000080" + // offset 128 to i = 1 + "0000000000000000000000000000000000000000000000000000000000000005" + // len(str[0]) = 5 + "68656c6c6f000000000000000000000000000000000000000000000000000000" + // str[0] + "0000000000000000000000000000000000000000000000000000000000000006" + // len(str[1]) = 6 + "666f6f6261720000000000000000000000000000000000000000000000000000"), // str[1] + }, + { + "string[2]", + []string{"hello", "foobar"}, + common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000040" + // offset to i = 0 + "0000000000000000000000000000000000000000000000000000000000000080" + // offset to i = 1 + "0000000000000000000000000000000000000000000000000000000000000005" + // len(str[0]) = 5 + "68656c6c6f000000000000000000000000000000000000000000000000000000" + // str[0] + "0000000000000000000000000000000000000000000000000000000000000006" + // len(str[1]) = 6 + "666f6f6261720000000000000000000000000000000000000000000000000000"), // str[1] + }, + { + "bytes32[][]", + [][]common.Hash{{{1}, {2}}, {{3}, {4}, {5}}}, + common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000002" + // len(array) = 2 + "0000000000000000000000000000000000000000000000000000000000000040" + // offset 64 to i = 0 + "00000000000000000000000000000000000000000000000000000000000000a0" + // offset 160 to i = 1 + "0000000000000000000000000000000000000000000000000000000000000002" + // len(array[0]) = 2 + "0100000000000000000000000000000000000000000000000000000000000000" + // array[0][0] + "0200000000000000000000000000000000000000000000000000000000000000" + // array[0][1] + "0000000000000000000000000000000000000000000000000000000000000003" + // len(array[1]) = 3 + "0300000000000000000000000000000000000000000000000000000000000000" + // array[1][0] + "0400000000000000000000000000000000000000000000000000000000000000" + // array[1][1] + "0500000000000000000000000000000000000000000000000000000000000000"), // array[1][2] + }, + + { + "bytes32[][2]", + [][]common.Hash{{{1}, {2}}, {{3}, {4}, {5}}}, + common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000040" + // offset 64 to i = 0 + "00000000000000000000000000000000000000000000000000000000000000a0" + // offset 160 to i = 1 + "0000000000000000000000000000000000000000000000000000000000000002" + // len(array[0]) = 2 + "0100000000000000000000000000000000000000000000000000000000000000" + // array[0][0] + "0200000000000000000000000000000000000000000000000000000000000000" + // array[0][1] + "0000000000000000000000000000000000000000000000000000000000000003" + // len(array[1]) = 3 + "0300000000000000000000000000000000000000000000000000000000000000" + // array[1][0] + "0400000000000000000000000000000000000000000000000000000000000000" + // array[1][1] + "0500000000000000000000000000000000000000000000000000000000000000"), // array[1][2] + }, + + { + "bytes32[3][2]", + [][]common.Hash{{{1}, {2}, {3}}, {{3}, {4}, {5}}}, + common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000" + // array[0][0] + "0200000000000000000000000000000000000000000000000000000000000000" + // array[0][1] + "0300000000000000000000000000000000000000000000000000000000000000" + // array[0][2] + "0300000000000000000000000000000000000000000000000000000000000000" + // array[1][0] + "0400000000000000000000000000000000000000000000000000000000000000" + // array[1][1] + "0500000000000000000000000000000000000000000000000000000000000000"), // array[1][2] + }, } { typ, err := NewType(test.typ) if err != nil { @@ -336,7 +396,7 @@ func TestPack(t *testing.T) { } if !bytes.Equal(output, test.output) { - t.Errorf("%d failed. Expected bytes: '%x' Got: '%x'", i, test.output, output) + t.Errorf("input %d for typ: %v failed. Expected bytes: '%x' Got: '%x'", i, typ.String(), test.output, output) } } } diff --git a/accounts/abi/type.go b/accounts/abi/type.go index dce89d2b4e..6bfaabf5a5 100644 --- a/accounts/abi/type.go +++ b/accounts/abi/type.go @@ -183,23 +183,39 @@ func (t Type) pack(v reflect.Value) ([]byte, error) { return nil, err } - if t.T == SliceTy || t.T == ArrayTy { - var packed []byte + switch t.T { + case SliceTy, ArrayTy: + var ret []byte + if t.requiresLengthPrefix() { + // append length + ret = append(ret, packNum(reflect.ValueOf(v.Len()))...) + } + + // calculate offset if any + offset := 0 + offsetReq := isDynamicType(*t.Elem) + if offsetReq { + offset = getDynamicTypeOffset(*t.Elem) * v.Len() + } + var tail []byte for i := 0; i < v.Len(); i++ { val, err := t.Elem.pack(v.Index(i)) if err != nil { return nil, err } - packed = append(packed, val...) - } - if t.T == SliceTy { - return packBytesSlice(packed, v.Len()), nil - } else if t.T == ArrayTy { - return packed, nil + if !offsetReq { + ret = append(ret, val...) + continue + } + ret = append(ret, packNum(reflect.ValueOf(offset))...) + offset += len(val) + tail = append(tail, val...) } + return append(ret, tail...), nil + default: + return packElement(t, v), nil } - return packElement(t, v), nil } // requireLengthPrefix returns whether the type requires any sort of length @@ -207,3 +223,27 @@ func (t Type) pack(v reflect.Value) ([]byte, error) { func (t Type) requiresLengthPrefix() bool { return t.T == StringTy || t.T == BytesTy || t.T == SliceTy } + +// isDynamicType returns true if the type is dynamic. +// StringTy, BytesTy, and SliceTy(irrespective of slice element type) are dynamic types +// ArrayTy is considered dynamic if and only if the Array element is a dynamic type. +// This function recursively checks the type for slice and array elements. +func isDynamicType(t Type) bool { + // dynamic types + // array is also a dynamic type if the array type is dynamic + return t.T == StringTy || t.T == BytesTy || t.T == SliceTy || (t.T == ArrayTy && isDynamicType(*t.Elem)) +} + +// getDynamicTypeOffset returns the offset for the type. +// See `isDynamicType` to know which types are considered dynamic. +// If the type t is an array and element type is not a dynamic type, then we consider it a static type and +// return 32 * size of array since length prefix is not required. +// If t is a dynamic type or element type(for slices and arrays) is dynamic, then we simply return 32 as offset. +func getDynamicTypeOffset(t Type) int { + // if it is an array and there are no dynamic types + // then the array is static type + if t.T == ArrayTy && !isDynamicType(*t.Elem) { + return 32 * t.Size + } + return 32 +}