summaryrefslogtreecommitdiffstats
path: root/src/core/file_sys/cheat_engine.cpp
blob: 09ca9d7050327d2ba27411505b1f8eb581625cc9 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
// Copyright 2018 yuzu emulator team
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.

#include <locale>
#include "common/hex_util.h"
#include "common/microprofile.h"
#include "common/swap.h"
#include "core/core.h"
#include "core/core_timing.h"
#include "core/core_timing_util.h"
#include "core/file_sys/cheat_engine.h"
#include "core/hle/kernel/process.h"
#include "core/hle/service/hid/controllers/controller_base.h"
#include "core/hle/service/hid/controllers/npad.h"
#include "core/hle/service/hid/hid.h"
#include "core/hle/service/sm/sm.h"

namespace FileSys {

constexpr u64 CHEAT_ENGINE_TICKS = Core::Timing::BASE_CLOCK_RATE / 60;
constexpr u32 KEYPAD_BITMASK = 0x3FFFFFF;

u64 Cheat::Address() const {
    u64 out;
    std::memcpy(&out, raw.data(), sizeof(u64));
    return Common::swap64(out) & 0xFFFFFFFFFF;
}

u64 Cheat::ValueWidth(u64 offset) const {
    return Value(offset, width);
}

u64 Cheat::Value(u64 offset, u64 width) const {
    u64 out;
    std::memcpy(&out, raw.data() + offset, sizeof(u64));
    out = Common::swap64(out);
    if (width == 8)
        return out;
    return out & ((1ull << (width * CHAR_BIT)) - 1);
}

u32 Cheat::KeypadValue() const {
    u32 out;
    std::memcpy(&out, raw.data(), sizeof(u32));
    return Common::swap32(out) & 0x0FFFFFFF;
}

void CheatList::SetMemoryParameters(VAddr main_begin, VAddr heap_begin, VAddr main_end,
                                    VAddr heap_end, MemoryWriter writer, MemoryReader reader) {
    this->main_region_begin = main_begin;
    this->main_region_end = main_end;
    this->heap_region_begin = heap_begin;
    this->heap_region_end = heap_end;
    this->writer = writer;
    this->reader = reader;
}

MICROPROFILE_DEFINE(Cheat_Engine, "Add-Ons", "Cheat Engine", MP_RGB(70, 200, 70));

void CheatList::Execute() {
    MICROPROFILE_SCOPE(Cheat_Engine);

    std::fill(scratch.begin(), scratch.end(), 0);
    in_standard = false;
    for (std::size_t i = 0; i < master_list.size(); ++i) {
        LOG_DEBUG(Common_Filesystem, "Executing block #{:08X} ({})", i, master_list[i].first);
        current_block = i;
        ExecuteBlock(master_list[i].second);
    }

    in_standard = true;
    for (std::size_t i = 0; i < standard_list.size(); ++i) {
        LOG_DEBUG(Common_Filesystem, "Executing block #{:08X} ({})", i, standard_list[i].first);
        current_block = i;
        ExecuteBlock(standard_list[i].second);
    }
}

CheatList::CheatList(ProgramSegment master, ProgramSegment standard)
    : master_list(master), standard_list(standard) {}

bool CheatList::EvaluateConditional(const Cheat& cheat) const {
    using ComparisonFunction = bool (*)(u64, u64);
    constexpr std::array<ComparisonFunction, 6> comparison_functions{
        [](u64 a, u64 b) { return a > b; },  [](u64 a, u64 b) { return a >= b; },
        [](u64 a, u64 b) { return a < b; },  [](u64 a, u64 b) { return a <= b; },
        [](u64 a, u64 b) { return a == b; }, [](u64 a, u64 b) { return a != b; },
    };

    if (cheat.type == CodeType::ConditionalInput) {
        const auto applet_resource = Core::System::GetInstance()
                                         .ServiceManager()
                                         .GetService<Service::HID::Hid>("hid")
                                         ->GetAppletResource();
        if (applet_resource == nullptr) {
            LOG_WARNING(
                Common_Filesystem,
                "Attempted to evaluate input conditional, but applet resource is not initialized!");
            return false;
        }

        const auto press_state =
            applet_resource
                ->GetController<Service::HID::Controller_NPad>(Service::HID::HidController::NPad)
                .GetAndResetPressState();
        return ((press_state & cheat.KeypadValue()) & KEYPAD_BITMASK) != 0;
    }

    ASSERT(cheat.type == CodeType::Conditional);

    const auto offset =
        cheat.memory_type == MemoryType::MainNSO ? main_region_begin : heap_region_begin;
    ASSERT(static_cast<u8>(cheat.comparison_op.Value()) < 6);
    auto* function = comparison_functions[static_cast<u8>(cheat.comparison_op.Value())];
    const auto addr = cheat.Address() + offset;

    return function(reader(cheat.width, SanitizeAddress(addr)), cheat.ValueWidth(8));
}

void CheatList::ProcessBlockPairs(const Block& block) {
    block_pairs.clear();

    u64 scope = 0;
    std::map<u64, u64> pairs;

    for (std::size_t i = 0; i < block.size(); ++i) {
        const auto& cheat = block[i];

        switch (cheat.type) {
        case CodeType::Conditional:
        case CodeType::ConditionalInput:
            pairs.insert_or_assign(scope, i);
            ++scope;
            break;
        case CodeType::EndConditional: {
            --scope;
            const auto idx = pairs.at(scope);
            block_pairs.insert_or_assign(idx, i);
            break;
        }
        case CodeType::Loop: {
            if (cheat.end_of_loop) {
                --scope;
                const auto idx = pairs.at(scope);
                block_pairs.insert_or_assign(idx, i);
            } else {
                pairs.insert_or_assign(scope, i);
                ++scope;
            }
            break;
        }
        }
    }
}

void CheatList::WriteImmediate(const Cheat& cheat) {
    const auto offset =
        cheat.memory_type == MemoryType::MainNSO ? main_region_begin : heap_region_begin;
    const auto& register_3 = scratch.at(cheat.register_3);

    const auto addr = cheat.Address() + offset + register_3;
    LOG_DEBUG(Common_Filesystem, "writing value={:016X} to addr={:016X}", addr,
              cheat.Value(8, cheat.width));
    writer(cheat.width, SanitizeAddress(addr), cheat.ValueWidth(8));
}

void CheatList::BeginConditional(const Cheat& cheat) {
    if (EvaluateConditional(cheat)) {
        return;
    }

    const auto iter = block_pairs.find(current_index);
    ASSERT(iter != block_pairs.end());
    current_index = iter->second - 1;
}

void CheatList::EndConditional(const Cheat& cheat) {
    LOG_DEBUG(Common_Filesystem, "Ending conditional block.");
}

void CheatList::Loop(const Cheat& cheat) {
    if (cheat.end_of_loop.Value())
        ASSERT(!cheat.end_of_loop.Value());

    auto& register_3 = scratch.at(cheat.register_3);
    const auto iter = block_pairs.find(current_index);
    ASSERT(iter != block_pairs.end());
    ASSERT(iter->first < iter->second);

    for (int i = cheat.Value(4, 4); i >= 0; --i) {
        register_3 = i;
        for (std::size_t c = iter->first + 1; c < iter->second; ++c) {
            current_index = c;
            ExecuteSingleCheat(
                (in_standard ? standard_list : master_list)[current_block].second[c]);
        }
    }

    current_index = iter->second;
}

void CheatList::LoadImmediate(const Cheat& cheat) {
    auto& register_3 = scratch.at(cheat.register_3);

    LOG_DEBUG(Common_Filesystem, "setting register={:01X} equal to value={:016X}", cheat.register_3,
              cheat.Value(4, 8));
    register_3 = cheat.Value(4, 8);
}

void CheatList::LoadIndexed(const Cheat& cheat) {
    const auto offset =
        cheat.memory_type == MemoryType::MainNSO ? main_region_begin : heap_region_begin;
    auto& register_3 = scratch.at(cheat.register_3);

    const auto addr = (cheat.load_from_register.Value() ? register_3 : offset) + cheat.Address();
    LOG_DEBUG(Common_Filesystem, "writing indexed value to register={:01X}, addr={:016X}",
              cheat.register_3, addr);
    register_3 = reader(cheat.width, SanitizeAddress(addr));
}

void CheatList::StoreIndexed(const Cheat& cheat) {
    const auto& register_3 = scratch.at(cheat.register_3);

    const auto addr =
        register_3 + (cheat.add_additional_register.Value() ? scratch.at(cheat.register_6) : 0);
    LOG_DEBUG(Common_Filesystem, "writing value={:016X} to addr={:016X}",
              cheat.Value(4, cheat.width), addr);
    writer(cheat.width, SanitizeAddress(addr), cheat.ValueWidth(4));
}

void CheatList::RegisterArithmetic(const Cheat& cheat) {
    using ArithmeticFunction = u64 (*)(u64, u64);
    constexpr std::array<ArithmeticFunction, 5> arithmetic_functions{
        [](u64 a, u64 b) { return a + b; },  [](u64 a, u64 b) { return a - b; },
        [](u64 a, u64 b) { return a * b; },  [](u64 a, u64 b) { return a << b; },
        [](u64 a, u64 b) { return a >> b; },
    };

    using ArithmeticOverflowCheck = bool (*)(u64, u64);
    constexpr std::array<ArithmeticOverflowCheck, 5> arithmetic_overflow_checks{
        [](u64 a, u64 b) { return a > (std::numeric_limits<u64>::max() - b); },       // a + b
        [](u64 a, u64 b) { return a > (std::numeric_limits<u64>::max() + b); },       // a - b
        [](u64 a, u64 b) { return a > (std::numeric_limits<u64>::max() / b); },       // a * b
        [](u64 a, u64 b) { return b >= 64 || (a & ~((1ull << (64 - b)) - 1)) != 0; }, // a << b
        [](u64 a, u64 b) { return b >= 64 || (a & ((1ull << b) - 1)) != 0; },         // a >> b
    };

    static_assert(sizeof(arithmetic_functions) == sizeof(arithmetic_overflow_checks),
                  "Missing or have extra arithmetic overflow checks compared to functions!");

    auto& register_3 = scratch.at(cheat.register_3);

    ASSERT(static_cast<u8>(cheat.arithmetic_op.Value()) < 5);
    auto* function = arithmetic_functions[static_cast<u8>(cheat.arithmetic_op.Value())];
    auto* overflow_function =
        arithmetic_overflow_checks[static_cast<u8>(cheat.arithmetic_op.Value())];
    LOG_DEBUG(Common_Filesystem, "performing arithmetic with register={:01X}, value={:016X}",
              cheat.register_3, cheat.ValueWidth(4));

    if (overflow_function(register_3, cheat.ValueWidth(4))) {
        LOG_WARNING(Common_Filesystem,
                    "overflow will occur when performing arithmetic operation={:02X} with operands "
                    "a={:016X}, b={:016X}!",
                    static_cast<u8>(cheat.arithmetic_op.Value()), register_3, cheat.ValueWidth(4));
    }

    register_3 = function(register_3, cheat.ValueWidth(4));
}

void CheatList::BeginConditionalInput(const Cheat& cheat) {
    if (EvaluateConditional(cheat))
        return;

    const auto iter = block_pairs.find(current_index);
    ASSERT(iter != block_pairs.end());
    current_index = iter->second - 1;
}

VAddr CheatList::SanitizeAddress(VAddr in) const {
    if ((in < main_region_begin || in >= main_region_end) &&
        (in < heap_region_begin || in >= heap_region_end)) {
        LOG_ERROR(Common_Filesystem,
                  "Cheat attempting to access memory at invalid address={:016X}, if this persists, "
                  "the cheat may be incorrect. However, this may be normal early in execution if "
                  "the game has not properly set up yet.",
                  in);
        return 0; ///< Invalid addresses will hard crash
    }

    return in;
}

void CheatList::ExecuteSingleCheat(const Cheat& cheat) {
    using CheatOperationFunction = void (CheatList::*)(const Cheat&);
    constexpr std::array<CheatOperationFunction, 9> cheat_operation_functions{
        &CheatList::WriteImmediate,        &CheatList::BeginConditional,
        &CheatList::EndConditional,        &CheatList::Loop,
        &CheatList::LoadImmediate,         &CheatList::LoadIndexed,
        &CheatList::StoreIndexed,          &CheatList::RegisterArithmetic,
        &CheatList::BeginConditionalInput,
    };

    const auto index = static_cast<u8>(cheat.type.Value());
    ASSERT(index < sizeof(cheat_operation_functions));
    const auto op = cheat_operation_functions[index];
    (this->*op)(cheat);
}

void CheatList::ExecuteBlock(const Block& block) {
    encountered_loops.clear();

    ProcessBlockPairs(block);
    for (std::size_t i = 0; i < block.size(); ++i) {
        current_index = i;
        ExecuteSingleCheat(block[i]);
        i = current_index;
    }
}

CheatParser::~CheatParser() = default;

CheatList CheatParser::MakeCheatList(CheatList::ProgramSegment master,
                                     CheatList::ProgramSegment standard) const {
    return {master, standard};
}

TextCheatParser::~TextCheatParser() = default;

CheatList TextCheatParser::Parse(const std::vector<u8>& data) const {
    std::stringstream ss;
    ss.write(reinterpret_cast<const char*>(data.data()), data.size());

    std::vector<std::string> lines;
    std::string stream_line;
    while (std::getline(ss, stream_line)) {
        // Remove a trailing \r
        if (!stream_line.empty() && stream_line.back() == '\r')
            stream_line.pop_back();
        lines.push_back(std::move(stream_line));
    }

    CheatList::ProgramSegment master_list;
    CheatList::ProgramSegment standard_list;

    for (std::size_t i = 0; i < lines.size(); ++i) {
        auto line = lines[i];

        if (!line.empty() && (line[0] == '[' || line[0] == '{')) {
            const auto master = line[0] == '{';
            const auto begin = master ? line.find('{') : line.find('[');
            const auto end = master ? line.rfind('}') : line.rfind(']');

            ASSERT(begin != std::string::npos && end != std::string::npos);

            const std::string patch_name{line.begin() + begin + 1, line.begin() + end};
            CheatList::Block block{};

            while (i < lines.size() - 1) {
                line = lines[++i];
                if (!line.empty() && (line[0] == '[' || line[0] == '{')) {
                    --i;
                    break;
                }

                if (line.size() < 8)
                    continue;

                Cheat out{};
                out.raw = ParseSingleLineCheat(line);
                block.push_back(out);
            }

            (master ? master_list : standard_list).emplace_back(patch_name, block);
        }
    }

    return MakeCheatList(master_list, standard_list);
}

std::array<u8, 16> TextCheatParser::ParseSingleLineCheat(const std::string& line) const {
    std::array<u8, 16> out{};

    if (line.size() < 8)
        return out;

    const auto word1 = Common::HexStringToArray<sizeof(u32)>(std::string_view{line.data(), 8});
    std::memcpy(out.data(), word1.data(), sizeof(u32));

    if (line.size() < 17 || line[8] != ' ')
        return out;

    const auto word2 = Common::HexStringToArray<sizeof(u32)>(std::string_view{line.data() + 9, 8});
    std::memcpy(out.data() + sizeof(u32), word2.data(), sizeof(u32));

    if (line.size() < 26 || line[17] != ' ') {
        // Perform shifting in case value is truncated early.
        const auto type = static_cast<CodeType>((out[0] & 0xF0) >> 4);
        if (type == CodeType::Loop || type == CodeType::LoadImmediate ||
            type == CodeType::StoreIndexed || type == CodeType::RegisterArithmetic) {
            std::memcpy(out.data() + 8, out.data() + 4, sizeof(u32));
            std::memset(out.data() + 4, 0, sizeof(u32));
        }

        return out;
    }

    const auto word3 = Common::HexStringToArray<sizeof(u32)>(std::string_view{line.data() + 18, 8});
    std::memcpy(out.data() + 2 * sizeof(u32), word3.data(), sizeof(u32));

    if (line.size() < 35 || line[26] != ' ') {
        // Perform shifting in case value is truncated early.
        const auto type = static_cast<CodeType>((out[0] & 0xF0) >> 4);
        if (type == CodeType::WriteImmediate || type == CodeType::Conditional) {
            std::memcpy(out.data() + 12, out.data() + 8, sizeof(u32));
            std::memset(out.data() + 8, 0, sizeof(u32));
        }

        return out;
    }

    const auto word4 = Common::HexStringToArray<sizeof(u32)>(std::string_view{line.data() + 27, 8});
    std::memcpy(out.data() + 3 * sizeof(u32), word4.data(), sizeof(u32));

    return out;
}

u64 MemoryReadImpl(u32 width, VAddr addr) {
    switch (width) {
    case 1:
        return Memory::Read8(addr);
    case 2:
        return Memory::Read16(addr);
    case 4:
        return Memory::Read32(addr);
    case 8:
        return Memory::Read64(addr);
    default:
        UNREACHABLE();
        return 0;
    }
}

void MemoryWriteImpl(u32 width, VAddr addr, u64 value) {
    switch (width) {
    case 1:
        Memory::Write8(addr, static_cast<u8>(value));
        break;
    case 2:
        Memory::Write16(addr, static_cast<u16>(value));
        break;
    case 4:
        Memory::Write32(addr, static_cast<u32>(value));
        break;
    case 8:
        Memory::Write64(addr, value);
        break;
    default:
        UNREACHABLE();
    }
}

CheatEngine::CheatEngine(std::vector<CheatList> cheats, const std::string& build_id,
                         VAddr code_region_start, VAddr code_region_end)
    : cheats(std::move(cheats)) {
    auto& core_timing{Core::System::GetInstance().CoreTiming()};
    event = core_timing.RegisterEvent(
        "CheatEngine::FrameCallback::" + build_id,
        [this](u64 userdata, s64 cycles_late) { FrameCallback(userdata, cycles_late); });
    core_timing.ScheduleEvent(CHEAT_ENGINE_TICKS, event);

    const auto& vm_manager = Core::System::GetInstance().CurrentProcess()->VMManager();
    for (auto& list : this->cheats) {
        list.SetMemoryParameters(code_region_start, vm_manager.GetHeapRegionBaseAddress(),
                                 code_region_end, vm_manager.GetHeapRegionEndAddress(),
                                 &MemoryWriteImpl, &MemoryReadImpl);
    }
}

CheatEngine::~CheatEngine() {
    auto& core_timing{Core::System::GetInstance().CoreTiming()};
    core_timing.UnscheduleEvent(event, 0);
}

void CheatEngine::FrameCallback(u64 userdata, int cycles_late) {
    for (auto& list : cheats)
        list.Execute();

    auto& core_timing{Core::System::GetInstance().CoreTiming()};
    core_timing.ScheduleEvent(CHEAT_ENGINE_TICKS - cycles_late, event);
}

} // namespace FileSys