solidity/test/Metadata.cpp

207 lines
5.1 KiB
C++

/*
This file is part of solidity.
solidity is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
solidity is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with solidity. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* @date 2017
* Metadata processing helpers.
*/
#include <string>
#include <iostream>
#include <libdevcore/Assertions.h>
#include <libdevcore/CommonData.h>
#include <libdevcore/JSON.h>
#include <test/Metadata.h>
using namespace std;
namespace dev
{
namespace test
{
bytes onlyMetadata(bytes const& _bytecode)
{
unsigned size = _bytecode.size();
if (size < 5)
return bytes{};
size_t metadataSize = (_bytecode[size - 2] << 8) + _bytecode[size - 1];
if (size < (metadataSize + 2))
return bytes{};
// Sanity check: assume the first byte is a fixed-size CBOR array with 1, 2 or 3 entries
unsigned char firstByte = _bytecode[size - metadataSize - 2];
if (firstByte != 0xa1 && firstByte != 0xa2 && firstByte != 0xa3)
return bytes{};
return bytes(_bytecode.end() - metadataSize - 2, _bytecode.end() - 2);
}
bytes bytecodeSansMetadata(bytes const& _bytecode)
{
unsigned metadataSize = onlyMetadata(_bytecode).size();
if (metadataSize == 0)
return bytes{};
return bytes(_bytecode.begin(), _bytecode.end() - metadataSize - 2);
}
string bytecodeSansMetadata(string const& _bytecode)
{
return toHex(bytecodeSansMetadata(fromHex(_bytecode, WhenError::Throw)));
}
DEV_SIMPLE_EXCEPTION(CBORException);
class TinyCBORParser
{
public:
explicit TinyCBORParser(bytes const& _metadata): m_pos(0), m_metadata(_metadata)
{
assertThrow((m_pos + 1) < _metadata.size(), CBORException, "Input too short.");
}
unsigned mapItemCount()
{
assertThrow(nextType() == MajorType::Map, CBORException, "Fixed-length map expected.");
return readLength();
}
string readKey()
{
return readString();
}
string readValue()
{
switch(nextType())
{
case MajorType::ByteString:
return toHex(readBytes(readLength()));
case MajorType::TextString:
return readString();
case MajorType::SimpleData:
{
unsigned value = nextImmediate();
m_pos++;
if (value == 20)
return "false";
else if (value == 21)
return "true";
else
assertThrow(false, CBORException, "Unsupported simple value (not a boolean).");
}
default:
assertThrow(false, CBORException, "Unsupported value type.");
}
}
private:
enum class MajorType
{
ByteString,
TextString,
Map,
SimpleData
};
MajorType nextType() const
{
unsigned value = (m_metadata.at(m_pos) >> 5) & 0x7;
switch (value)
{
case 2: return MajorType::ByteString;
case 3: return MajorType::TextString;
case 5: return MajorType::Map;
case 7: return MajorType::SimpleData;
default: assertThrow(false, CBORException, "Unsupported major type.");
}
}
unsigned nextImmediate() const { return m_metadata.at(m_pos) & 0x1f; }
unsigned readLength()
{
unsigned length = m_metadata.at(m_pos++) & 0x1f;
if (length < 24)
return length;
if (length == 24)
return m_metadata.at(m_pos++);
// Unsupported length kind. (Only by this parser.)
assertThrow(false, CBORException, string("Unsupported length ") + to_string(length));
}
bytes readBytes(unsigned length)
{
bytes ret{m_metadata.begin() + m_pos, m_metadata.begin() + m_pos + length};
m_pos += length;
return ret;
}
string readString()
{
// Expect a text string.
assertThrow(nextType() == MajorType::TextString, CBORException, "String expected.");
bytes tmp{readBytes(readLength())};
return string{tmp.begin(), tmp.end()};
}
unsigned m_pos;
bytes const& m_metadata;
};
std::optional<map<string, string>> parseCBORMetadata(bytes const& _metadata)
{
try
{
TinyCBORParser parser(_metadata);
map<string, string> ret;
unsigned count = parser.mapItemCount();
for (unsigned i = 0; i < count; i++)
{
string key = parser.readKey();
string value = parser.readValue();
ret[move(key)] = move(value);
}
return ret;
}
catch (CBORException const&)
{
return {};
}
}
bool isValidMetadata(string const& _metadata)
{
Json::Value metadata;
if (!jsonParseStrict(_metadata, metadata))
return false;
if (
!metadata.isObject() ||
!metadata.isMember("version") ||
!metadata.isMember("language") ||
!metadata.isMember("compiler") ||
!metadata.isMember("settings") ||
!metadata.isMember("sources") ||
!metadata.isMember("output") ||
!metadata["settings"].isMember("evmVersion") ||
!metadata["settings"].isMember("metadata") ||
!metadata["settings"]["metadata"].isMember("bytecodeHash")
)
return false;
if (!metadata["version"].isNumeric() || metadata["version"] != 1)
return false;
if (!metadata["language"].isString() || metadata["language"].asString() != "Solidity")
return false;
/// @TODO add more strict checks
return true;
}
}
} // end namespaces