dfhack/plugins/devel/check-structures-sanity.cpp

542 lines
13 KiB
C++

#include "Console.h"
#include "PluginManager.h"
#include "MemAccess.h"
#include "DataDefs.h"
#include "DataIdentity.h"
#include <set>
#include <typeinfo>
using namespace DFHack;
DFHACK_PLUGIN("check-structures-sanity");
static command_result command(color_ostream &, std::vector<std::string> &);
#ifdef WIN32
#define UNEXPECTED __debugbreak()
#else
#define UNEXPECTED __asm__ volatile ("int $0x03")
#endif
DFhackCExport command_result plugin_init(color_ostream & out, std::vector<PluginCommand> & commands)
{
commands.push_back(PluginCommand(
"check-structures-sanity",
"performs a sanity check on df-structures",
command,
false,
"checks structures to make sure vectors aren't misidentified"
));
return CR_OK;
}
class Checker
{
color_ostream & out;
std::vector<t_memrange> mapped;
std::set<void *> seen_addr;
std::vector<std::string> path;
bool ok;
bool check_access(void *, type_identity *);
void *safe_dereference(void *, ptrdiff_t = 0);
void check_global(global_identity *);
void check_fields(void *, const struct_field_info *);
void check_field(void *, const struct_field_info *);
void check_item(void *, type_identity *);
void check_pointer(void *, type_identity *);
void check_static_array(void *, type_identity *, size_t);
void check_container(void *, container_identity *);
void check_vector(void *, container_identity *, type_identity *);
void check_deque(void *, container_identity *, type_identity *);
void check_bit_container(void *, container_identity *);
void check_virtual(void *, virtual_identity *);
class Scope
{
Checker *parent;
public:
Scope(Checker *, const std::string &);
Scope(Checker *, size_t);
Scope(const Scope &) = delete;
~Scope();
};
public:
Checker(color_ostream &);
bool check();
};
static command_result command(color_ostream & out, std::vector<std::string> & parameters)
{
if (!parameters.empty())
{
return CR_WRONG_USAGE;
}
CoreSuspender suspend;
Checker checker(out);
return checker.check() ? CR_OK : CR_FAILURE;
}
Checker::Checker(color_ostream & out) :
out(out)
{
Core::getInstance().p->getMemRanges(mapped);
}
bool Checker::check()
{
seen_addr.clear();
ok = true;
check_global(&df::global::_identity);
return ok;
}
Checker::Scope::Scope(Checker *parent, const std::string & name) :
parent(parent)
{
parent->path.push_back(name);
}
Checker::Scope::Scope(Checker *parent, size_t index) :
Scope(parent, stl_sprintf("[%lu]", index))
{
}
Checker::Scope::~Scope()
{
parent->path.pop_back();
}
#define FAIL(message) \
do \
{ \
ok = false; \
out << COLOR_LIGHTRED << "sanity check failed (line " << __LINE__ << "): "; \
out << COLOR_RESET << (identity ? identity->getFullName() : "?") << " (accessed as "; \
for (auto & p : path) { out << p; } \
out << "): "; \
out << COLOR_YELLOW << message; \
out << COLOR_RESET << std::endl; \
} while (false)
#define PTR_ADD(base, offset) (reinterpret_cast<void *>(reinterpret_cast<uintptr_t>((base)) + static_cast<ptrdiff_t>((offset))))
bool Checker::check_access(void *base, type_identity *identity)
{
if (!base)
{
// null pointer: can't access, but not an error
return false;
}
for (auto & range : mapped)
{
if (!range.isInRange(base))
{
continue;
}
if (!range.valid || !range.read)
{
FAIL("pointer to invalid memory range");
return false;
}
if (identity && !range.isInRange(PTR_ADD(base, identity->byte_size())))
{
FAIL("pointer exceeds mapped memory bounds");
return false;
}
return true;
}
FAIL("pointer not in any mapped range");
return false;
}
void *Checker::safe_dereference(void *base, ptrdiff_t offset)
{
if (!base)
{
return nullptr;
}
type_identity *identity = nullptr; // void
for (auto & range : mapped)
{
if (!range.isInRange(base))
{
continue;
}
if (!range.valid || !range.read)
{
return nullptr;
}
if (!range.isInRange(PTR_ADD(base, offset)))
{
return nullptr;
}
return *reinterpret_cast<void **>(PTR_ADD(base, offset));
}
return nullptr;
}
void Checker::check_global(global_identity *identity)
{
Scope scope(this, "df::global::");
for (auto field = identity->getFields(); field->mode != struct_field_info::END; field++)
{
if (!field->offset)
{
Scope scope_2(this, field->name);
FAIL("global address is unknown");
continue;
}
auto base = reinterpret_cast<void **>(field->offset);
if (!seen_addr.insert(base).second)
{
continue;
}
check_field(*base, field);
}
}
void Checker::check_fields(void *base, const struct_field_info *fields)
{
for (auto field = fields; field->mode != struct_field_info::END; field++)
{
check_field(PTR_ADD(base, field->offset), field);
}
}
void Checker::check_field(void *base, const struct_field_info *field)
{
Scope scope(this, field->name);
switch (field->mode)
{
case struct_field_info::END:
// can't happen - already checked
break;
case struct_field_info::PRIMITIVE:
// don't need to check primitives
break;
case struct_field_info::STATIC_STRING:
// TODO: check static strings?
break;
case struct_field_info::POINTER:
check_pointer(base, field->type);
break;
case struct_field_info::STATIC_ARRAY:
check_static_array(base, field->type, field->count);
break;
case struct_field_info::SUBSTRUCT:
check_item(base, field->type);
break;
case struct_field_info::CONTAINER:
check_container(base, static_cast<container_identity *>(field->type));
break;
case struct_field_info::STL_VECTOR_PTR:
{
df::stl_ptr_vector_identity temp_identity(field->type, field->eid);
check_container(base, &temp_identity);
}
break;
case struct_field_info::OBJ_METHOD:
// ignore
break;
case struct_field_info::CLASS_METHOD:
// ignore
break;
}
}
void Checker::check_item(void *base, type_identity *identity)
{
if (!identity)
{
// void
return;
}
switch (identity->type())
{
case IDTYPE_GLOBAL:
// impossible
break;
case IDTYPE_FUNCTION:
// ignore
break;
case IDTYPE_PRIMITIVE:
// don't need to check primitives
break;
case IDTYPE_POINTER:
check_pointer(base, static_cast<pointer_identity *>(identity)->getTarget());
break;
case IDTYPE_CONTAINER:
case IDTYPE_BIT_CONTAINER:
case IDTYPE_PTR_CONTAINER:
case IDTYPE_STL_PTR_VECTOR:
check_container(base, static_cast<container_identity *>(identity));
break;
case IDTYPE_BITFIELD:
// TODO: check bitfields?
break;
case IDTYPE_ENUM:
// TODO: check enums?
break;
case IDTYPE_STRUCT:
{
Scope scope(this, ".");
check_fields(base, static_cast<struct_identity *>(identity)->getFields());
}
break;
case IDTYPE_CLASS:
check_virtual(base, static_cast<virtual_identity *>(identity));
break;
case IDTYPE_BUFFER:
{
auto item_identity = static_cast<container_identity *>(identity)->getItemType();
check_static_array(base, item_identity, identity->byte_size() / item_identity->byte_size());
}
break;
case IDTYPE_OPAQUE:
// can't check opaque types
break;
}
}
void Checker::check_pointer(void *base, type_identity *identity)
{
if (!seen_addr.insert(base).second)
{
return;
}
if (!identity)
{
// void pointer
return;
}
auto ptr = *reinterpret_cast<void **>(base);
if (!check_access(ptr, identity))
{
return;
}
check_item(ptr, identity);
}
void Checker::check_static_array(void *base, type_identity *identity, size_t count)
{
if (identity->isPrimitive())
{
return;
}
size_t item_size = identity->byte_size();
for (size_t i = 0; i < count; i++)
{
Scope scope(this, i);
check_item(PTR_ADD(base, item_size * i), identity);
}
}
void Checker::check_container(void *base, container_identity *identity)
{
if (identity->type() == IDTYPE_STRUCT)
{
// DfLinkedList
check_item(base, identity);
return;
}
if (!seen_addr.insert(base).second)
{
return;
}
if (identity->type() == IDTYPE_BIT_CONTAINER)
{
check_bit_container(base, identity);
return;
}
auto item_identity = identity->getItemType();
pointer_identity item_ptr_identity(item_identity);
if (identity->type() == IDTYPE_PTR_CONTAINER || identity->type() == IDTYPE_STL_PTR_VECTOR)
{
item_identity = &item_ptr_identity;
}
else if (identity->type() != IDTYPE_CONTAINER)
{
// unexpected
return;
}
auto void_name = identity->getFullName(nullptr);
if (void_name == "vector<void>" || void_name == "vector<void*>")
{
check_vector(base, identity, item_identity);
}
else if (void_name == "deque<void>")
{
check_deque(base, identity, item_identity);
}
else
{
FAIL("TODO: " << void_name);
UNEXPECTED;
}
}
void Checker::check_vector(void *base, container_identity *identity, type_identity *item_identity)
{
struct vector_data
{
uintptr_t start;
uintptr_t finish;
uintptr_t end_of_storage;
};
if (identity->byte_size() != sizeof(vector_data) || identity->getFullName().find("vector<") != 0)
{
UNEXPECTED;
return;
}
vector_data vector = *reinterpret_cast<vector_data *>(base);
size_t item_size = item_identity->byte_size();
ptrdiff_t length = vector.finish - vector.start;
ptrdiff_t capacity = vector.end_of_storage - vector.start;
bool local_ok = true;
if (vector.start > vector.finish)
{
local_ok = false;
FAIL("vector length is negative (" << (length / ssize_t(item_size)) << ")");
}
if (vector.start > vector.end_of_storage)
{
local_ok = false;
FAIL("vector capacity is negative (" << (capacity / ssize_t(item_size)) << ")");
}
else if (vector.finish > vector.end_of_storage)
{
local_ok = false;
FAIL("vector capacity (" << (capacity / ssize_t(item_size)) << ") is less than its length (" << (length / ssize_t(item_size)) << ")");
}
size_t ulength = size_t(length);
size_t ucapacity = size_t(capacity);
if (ulength % item_size != 0)
{
local_ok = false;
FAIL("vector length is non-integer (" << (ulength / item_size) << " items plus " << (ulength % item_size) << " bytes)");
}
if (ucapacity % item_size != 0)
{
local_ok = false;
FAIL("vector capacity is non-integer (" << (ucapacity / item_size) << " items plus " << (ucapacity % item_size) << " bytes)");
}
if (local_ok)
{
check_static_array(reinterpret_cast<void *>(vector.start), item_identity, ulength / item_size);
}
}
void Checker::check_deque(void *base, container_identity *identity, type_identity *item_identity)
{
// TODO: check deque?
}
void Checker::check_bit_container(void *base, container_identity *identity)
{
if (identity->getFullName() == "BitArray<>")
{
// TODO: check DFHack::BitArray?
return;
}
struct biterator_data
{
uintptr_t ptr;
unsigned int offset;
};
struct bvector_data
{
biterator_data start;
biterator_data finish;
uintptr_t end_of_storage;
};
if (identity->byte_size() != sizeof(bvector_data) || identity->getFullName() != "vector<bool>")
{
UNEXPECTED;
return;
}
// TODO: check vector<bool>?
}
void Checker::check_virtual(void *base, virtual_identity *identity)
{
if (!seen_addr.insert(base).second)
{
return;
}
if (!base)
{
// null pointer
return;
}
auto ptr = reinterpret_cast<virtual_ptr>(base);
if (!identity->is_instance(ptr))
{
FAIL("vtable is not a known subclass");
// write separately to avoid losing the previous line if this segfaults
void *vtable = *reinterpret_cast<void **>(base);
if (!vtable)
{
FAIL("(vtable is null)");
UNEXPECTED;
return;
}
auto class_name = Core::getInstance().p->readClassName(vtable);
FAIL("(subclass is " << class_name << ")");
return;
}
Scope scope(this, ".");
check_fields(base, identity->getFields());
}