summaryrefslogtreecommitdiffstats
path: root/src/core/file_sys/content_archive.cpp
blob: 79bfb6fecf22dc55ce70b8146741070f04be2914 (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
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
// Copyright 2018 yuzu emulator team
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.

#include <algorithm>
#include <cstring>
#include <utility>

#include <boost/optional.hpp>

#include "common/logging/log.h"
#include "core/crypto/aes_util.h"
#include "core/crypto/ctr_encryption_layer.h"
#include "core/file_sys/content_archive.h"
#include "core/file_sys/nca_patch.h"
#include "core/file_sys/partition_filesystem.h"
#include "core/file_sys/romfs.h"
#include "core/file_sys/vfs_offset.h"
#include "core/loader/loader.h"

namespace FileSys {

// Media offsets in headers are stored divided by 512. Mult. by this to get real offset.
constexpr u64 MEDIA_OFFSET_MULTIPLIER = 0x200;

constexpr u64 SECTION_HEADER_SIZE = 0x200;
constexpr u64 SECTION_HEADER_OFFSET = 0x400;

constexpr u32 IVFC_MAX_LEVEL = 6;

enum class NCASectionFilesystemType : u8 {
    PFS0 = 0x2,
    ROMFS = 0x3,
};

struct NCASectionHeaderBlock {
    INSERT_PADDING_BYTES(3);
    NCASectionFilesystemType filesystem_type;
    NCASectionCryptoType crypto_type;
    INSERT_PADDING_BYTES(3);
};
static_assert(sizeof(NCASectionHeaderBlock) == 0x8, "NCASectionHeaderBlock has incorrect size.");

struct NCASectionRaw {
    NCASectionHeaderBlock header;
    std::array<u8, 0x138> block_data;
    std::array<u8, 0x8> section_ctr;
    INSERT_PADDING_BYTES(0xB8);
};
static_assert(sizeof(NCASectionRaw) == 0x200, "NCASectionRaw has incorrect size.");

struct PFS0Superblock {
    NCASectionHeaderBlock header_block;
    std::array<u8, 0x20> hash;
    u32_le size;
    INSERT_PADDING_BYTES(4);
    u64_le hash_table_offset;
    u64_le hash_table_size;
    u64_le pfs0_header_offset;
    u64_le pfs0_size;
    INSERT_PADDING_BYTES(0x1B0);
};
static_assert(sizeof(PFS0Superblock) == 0x200, "PFS0Superblock has incorrect size.");

struct RomFSSuperblock {
    NCASectionHeaderBlock header_block;
    IVFCHeader ivfc;
    INSERT_PADDING_BYTES(0x118);
};
static_assert(sizeof(RomFSSuperblock) == 0x200, "RomFSSuperblock has incorrect size.");

struct BKTRHeader {
    u64_le offset;
    u64_le size;
    u32_le magic;
    INSERT_PADDING_BYTES(0x4);
    u32_le number_entries;
    INSERT_PADDING_BYTES(0x4);
};
static_assert(sizeof(BKTRHeader) == 0x20, "BKTRHeader has incorrect size.");

struct BKTRSuperblock {
    NCASectionHeaderBlock header_block;
    IVFCHeader ivfc;
    INSERT_PADDING_BYTES(0x18);
    BKTRHeader relocation;
    BKTRHeader subsection;
    INSERT_PADDING_BYTES(0xC0);
};
static_assert(sizeof(BKTRSuperblock) == 0x200, "BKTRSuperblock has incorrect size.");

union NCASectionHeader {
    NCASectionRaw raw;
    PFS0Superblock pfs0;
    RomFSSuperblock romfs;
    BKTRSuperblock bktr;
};
static_assert(sizeof(NCASectionHeader) == 0x200, "NCASectionHeader has incorrect size.");

bool IsValidNCA(const NCAHeader& header) {
    // TODO(DarkLordZach): Add NCA2/NCA0 support.
    return header.magic == Common::MakeMagic('N', 'C', 'A', '3');
}

u8 NCA::GetCryptoRevision() const {
    u8 master_key_id = header.crypto_type;
    if (header.crypto_type_2 > master_key_id)
        master_key_id = header.crypto_type_2;
    if (master_key_id > 0)
        --master_key_id;
    return master_key_id;
}

boost::optional<Core::Crypto::Key128> NCA::GetKeyAreaKey(NCASectionCryptoType type) const {
    const auto master_key_id = GetCryptoRevision();

    if (!keys.HasKey(Core::Crypto::S128KeyType::KeyArea, master_key_id, header.key_index))
        return boost::none;

    std::vector<u8> key_area(header.key_area.begin(), header.key_area.end());
    Core::Crypto::AESCipher<Core::Crypto::Key128> cipher(
        keys.GetKey(Core::Crypto::S128KeyType::KeyArea, master_key_id, header.key_index),
        Core::Crypto::Mode::ECB);
    cipher.Transcode(key_area.data(), key_area.size(), key_area.data(), Core::Crypto::Op::Decrypt);

    Core::Crypto::Key128 out;
    if (type == NCASectionCryptoType::XTS)
        std::copy(key_area.begin(), key_area.begin() + 0x10, out.begin());
    else if (type == NCASectionCryptoType::CTR || type == NCASectionCryptoType::BKTR)
        std::copy(key_area.begin() + 0x20, key_area.begin() + 0x30, out.begin());
    else
        LOG_CRITICAL(Crypto, "Called GetKeyAreaKey on invalid NCASectionCryptoType type={:02X}",
                     static_cast<u8>(type));
    u128 out_128{};
    memcpy(out_128.data(), out.data(), 16);
    LOG_DEBUG(Crypto, "called with crypto_rev={:02X}, kak_index={:02X}, key={:016X}{:016X}",
              master_key_id, header.key_index, out_128[1], out_128[0]);

    return out;
}

boost::optional<Core::Crypto::Key128> NCA::GetTitlekey() {
    const auto master_key_id = GetCryptoRevision();

    u128 rights_id{};
    memcpy(rights_id.data(), header.rights_id.data(), 16);
    if (rights_id == u128{}) {
        status = Loader::ResultStatus::ErrorInvalidRightsID;
        return boost::none;
    }

    auto titlekey = keys.GetKey(Core::Crypto::S128KeyType::Titlekey, rights_id[1], rights_id[0]);
    if (titlekey == Core::Crypto::Key128{}) {
        status = Loader::ResultStatus::ErrorMissingTitlekey;
        return boost::none;
    }

    if (!keys.HasKey(Core::Crypto::S128KeyType::Titlekek, master_key_id)) {
        status = Loader::ResultStatus::ErrorMissingTitlekek;
        return boost::none;
    }

    Core::Crypto::AESCipher<Core::Crypto::Key128> cipher(
        keys.GetKey(Core::Crypto::S128KeyType::Titlekek, master_key_id), Core::Crypto::Mode::ECB);
    cipher.Transcode(titlekey.data(), titlekey.size(), titlekey.data(), Core::Crypto::Op::Decrypt);

    return titlekey;
}

VirtualFile NCA::Decrypt(NCASectionHeader s_header, VirtualFile in, u64 starting_offset) {
    if (!encrypted)
        return in;

    switch (s_header.raw.header.crypto_type) {
    case NCASectionCryptoType::NONE:
        LOG_DEBUG(Crypto, "called with mode=NONE");
        return in;
    case NCASectionCryptoType::CTR:
    // During normal BKTR decryption, this entire function is skipped. This is for the metadata,
    // which uses the same CTR as usual.
    case NCASectionCryptoType::BKTR:
        LOG_DEBUG(Crypto, "called with mode=CTR, starting_offset={:016X}", starting_offset);
        {
            boost::optional<Core::Crypto::Key128> key = boost::none;
            if (has_rights_id) {
                status = Loader::ResultStatus::Success;
                key = GetTitlekey();
                if (key == boost::none) {
                    if (status == Loader::ResultStatus::Success)
                        status = Loader::ResultStatus::ErrorMissingTitlekey;
                    return nullptr;
                }
            } else {
                key = GetKeyAreaKey(NCASectionCryptoType::CTR);
                if (key == boost::none) {
                    status = Loader::ResultStatus::ErrorMissingKeyAreaKey;
                    return nullptr;
                }
            }

            auto out = std::make_shared<Core::Crypto::CTREncryptionLayer>(
                std::move(in), key.value(), starting_offset);
            std::vector<u8> iv(16);
            for (u8 i = 0; i < 8; ++i)
                iv[i] = s_header.raw.section_ctr[0x8 - i - 1];
            out->SetIV(iv);
            return std::static_pointer_cast<VfsFile>(out);
        }
    case NCASectionCryptoType::XTS:
        // TODO(DarkLordZach): Find a test case for XTS-encrypted NCAs
    default:
        LOG_ERROR(Crypto, "called with unhandled crypto type={:02X}",
                  static_cast<u8>(s_header.raw.header.crypto_type));
        return nullptr;
    }
}

NCA::NCA(VirtualFile file_, VirtualFile bktr_base_romfs_, u64 bktr_base_ivfc_offset)
    : file(std::move(file_)),
      bktr_base_romfs(bktr_base_romfs_ ? std::move(bktr_base_romfs_) : nullptr) {
    status = Loader::ResultStatus::Success;

    if (file == nullptr) {
        status = Loader::ResultStatus::ErrorNullFile;
        return;
    }

    if (sizeof(NCAHeader) != file->ReadObject(&header)) {
        LOG_ERROR(Loader, "File reader errored out during header read.");
        status = Loader::ResultStatus::ErrorBadNCAHeader;
        return;
    }

    encrypted = false;

    if (!IsValidNCA(header)) {
        if (header.magic == Common::MakeMagic('N', 'C', 'A', '2')) {
            status = Loader::ResultStatus::ErrorNCA2;
            return;
        }
        if (header.magic == Common::MakeMagic('N', 'C', 'A', '0')) {
            status = Loader::ResultStatus::ErrorNCA0;
            return;
        }

        NCAHeader dec_header{};
        Core::Crypto::AESCipher<Core::Crypto::Key256> cipher(
            keys.GetKey(Core::Crypto::S256KeyType::Header), Core::Crypto::Mode::XTS);
        cipher.XTSTranscode(&header, sizeof(NCAHeader), &dec_header, 0, 0x200,
                            Core::Crypto::Op::Decrypt);
        if (IsValidNCA(dec_header)) {
            header = dec_header;
            encrypted = true;
        } else {
            if (dec_header.magic == Common::MakeMagic('N', 'C', 'A', '2')) {
                status = Loader::ResultStatus::ErrorNCA2;
                return;
            }
            if (dec_header.magic == Common::MakeMagic('N', 'C', 'A', '0')) {
                status = Loader::ResultStatus::ErrorNCA0;
                return;
            }

            if (!keys.HasKey(Core::Crypto::S256KeyType::Header))
                status = Loader::ResultStatus::ErrorMissingHeaderKey;
            else
                status = Loader::ResultStatus::ErrorIncorrectHeaderKey;
            return;
        }
    }

    has_rights_id = std::find_if_not(header.rights_id.begin(), header.rights_id.end(),
                                     [](char c) { return c == '\0'; }) != header.rights_id.end();

    const std::ptrdiff_t number_sections =
        std::count_if(std::begin(header.section_tables), std::end(header.section_tables),
                      [](NCASectionTableEntry entry) { return entry.media_offset > 0; });

    std::vector<NCASectionHeader> sections(number_sections);
    const auto length_sections = SECTION_HEADER_SIZE * number_sections;

    if (encrypted) {
        auto raw = file->ReadBytes(length_sections, SECTION_HEADER_OFFSET);
        Core::Crypto::AESCipher<Core::Crypto::Key256> cipher(
            keys.GetKey(Core::Crypto::S256KeyType::Header), Core::Crypto::Mode::XTS);
        cipher.XTSTranscode(raw.data(), length_sections, sections.data(), 2, SECTION_HEADER_SIZE,
                            Core::Crypto::Op::Decrypt);
    } else {
        file->ReadBytes(sections.data(), length_sections, SECTION_HEADER_OFFSET);
    }

    is_update = std::find_if(sections.begin(), sections.end(), [](const NCASectionHeader& header) {
                    return header.raw.header.crypto_type == NCASectionCryptoType::BKTR;
                }) != sections.end();
    ivfc_offset = 0;

    for (std::ptrdiff_t i = 0; i < number_sections; ++i) {
        auto section = sections[i];

        if (section.raw.header.filesystem_type == NCASectionFilesystemType::ROMFS) {
            const size_t base_offset =
                header.section_tables[i].media_offset * MEDIA_OFFSET_MULTIPLIER;
            ivfc_offset = section.romfs.ivfc.levels[IVFC_MAX_LEVEL - 1].offset;
            const size_t romfs_offset = base_offset + ivfc_offset;
            const size_t romfs_size = section.romfs.ivfc.levels[IVFC_MAX_LEVEL - 1].size;
            auto raw = std::make_shared<OffsetVfsFile>(file, romfs_size, romfs_offset);
            auto dec = Decrypt(section, raw, romfs_offset);

            if (dec == nullptr) {
                if (status != Loader::ResultStatus::Success)
                    return;
                if (has_rights_id)
                    status = Loader::ResultStatus::ErrorIncorrectTitlekeyOrTitlekek;
                else
                    status = Loader::ResultStatus::ErrorIncorrectKeyAreaKey;
                return;
            }

            if (section.raw.header.crypto_type == NCASectionCryptoType::BKTR) {
                if (section.bktr.relocation.magic != Common::MakeMagic('B', 'K', 'T', 'R') ||
                    section.bktr.subsection.magic != Common::MakeMagic('B', 'K', 'T', 'R')) {
                    status = Loader::ResultStatus::ErrorBadBKTRHeader;
                    return;
                }

                if (section.bktr.relocation.offset + section.bktr.relocation.size !=
                    section.bktr.subsection.offset) {
                    status = Loader::ResultStatus::ErrorBKTRSubsectionNotAfterRelocation;
                    return;
                }

                const u64 size =
                    MEDIA_OFFSET_MULTIPLIER * (header.section_tables[i].media_end_offset -
                                               header.section_tables[i].media_offset);
                if (section.bktr.subsection.offset + section.bktr.subsection.size != size) {
                    status = Loader::ResultStatus::ErrorBKTRSubsectionNotAtEnd;
                    return;
                }

                const u64 offset = section.romfs.ivfc.levels[IVFC_MAX_LEVEL - 1].offset;
                RelocationBlock relocation_block{};
                if (dec->ReadObject(&relocation_block, section.bktr.relocation.offset - offset) !=
                    sizeof(RelocationBlock)) {
                    status = Loader::ResultStatus::ErrorBadRelocationBlock;
                    return;
                }
                SubsectionBlock subsection_block{};
                if (dec->ReadObject(&subsection_block, section.bktr.subsection.offset - offset) !=
                    sizeof(RelocationBlock)) {
                    status = Loader::ResultStatus::ErrorBadSubsectionBlock;
                    return;
                }

                std::vector<RelocationBucketRaw> relocation_buckets_raw(
                    (section.bktr.relocation.size - sizeof(RelocationBlock)) /
                    sizeof(RelocationBucketRaw));
                if (dec->ReadBytes(relocation_buckets_raw.data(),
                                   section.bktr.relocation.size - sizeof(RelocationBlock),
                                   section.bktr.relocation.offset + sizeof(RelocationBlock) -
                                       offset) !=
                    section.bktr.relocation.size - sizeof(RelocationBlock)) {
                    status = Loader::ResultStatus::ErrorBadRelocationBuckets;
                    return;
                }

                std::vector<SubsectionBucketRaw> subsection_buckets_raw(
                    (section.bktr.subsection.size - sizeof(SubsectionBlock)) /
                    sizeof(SubsectionBucketRaw));
                if (dec->ReadBytes(subsection_buckets_raw.data(),
                                   section.bktr.subsection.size - sizeof(SubsectionBlock),
                                   section.bktr.subsection.offset + sizeof(SubsectionBlock) -
                                       offset) !=
                    section.bktr.subsection.size - sizeof(SubsectionBlock)) {
                    status = Loader::ResultStatus::ErrorBadSubsectionBuckets;
                    return;
                }

                std::vector<RelocationBucket> relocation_buckets(relocation_buckets_raw.size());
                std::transform(relocation_buckets_raw.begin(), relocation_buckets_raw.end(),
                               relocation_buckets.begin(), &ConvertRelocationBucketRaw);
                std::vector<SubsectionBucket> subsection_buckets(subsection_buckets_raw.size());
                std::transform(subsection_buckets_raw.begin(), subsection_buckets_raw.end(),
                               subsection_buckets.begin(), &ConvertSubsectionBucketRaw);

                u32 ctr_low;
                std::memcpy(&ctr_low, section.raw.section_ctr.data(), sizeof(ctr_low));
                subsection_buckets.back().entries.push_back(
                    {section.bktr.relocation.offset, {0}, ctr_low});
                subsection_buckets.back().entries.push_back({size, {0}, 0});

                boost::optional<Core::Crypto::Key128> key = boost::none;
                if (encrypted) {
                    if (has_rights_id) {
                        status = Loader::ResultStatus::Success;
                        key = GetTitlekey();
                        if (key == boost::none) {
                            status = Loader::ResultStatus::ErrorMissingTitlekey;
                            return;
                        }
                    } else {
                        key = GetKeyAreaKey(NCASectionCryptoType::BKTR);
                        if (key == boost::none) {
                            status = Loader::ResultStatus::ErrorMissingKeyAreaKey;
                            return;
                        }
                    }
                }

                if (bktr_base_romfs == nullptr) {
                    status = Loader::ResultStatus::ErrorMissingBKTRBaseRomFS;
                    return;
                }

                auto bktr = std::make_shared<BKTR>(
                    bktr_base_romfs, std::make_shared<OffsetVfsFile>(file, romfs_size, base_offset),
                    relocation_block, relocation_buckets, subsection_block, subsection_buckets,
                    encrypted, encrypted ? key.get() : Core::Crypto::Key128{}, base_offset,
                    bktr_base_ivfc_offset, section.raw.section_ctr);

                // BKTR applies to entire IVFC, so make an offset version to level 6

                files.push_back(std::make_shared<OffsetVfsFile>(
                    bktr, romfs_size, section.romfs.ivfc.levels[IVFC_MAX_LEVEL - 1].offset));
                romfs = files.back();
            } else {
                files.push_back(std::move(dec));
                romfs = files.back();
            }
        } else if (section.raw.header.filesystem_type == NCASectionFilesystemType::PFS0) {
            u64 offset = (static_cast<u64>(header.section_tables[i].media_offset) *
                          MEDIA_OFFSET_MULTIPLIER) +
                         section.pfs0.pfs0_header_offset;
            u64 size = MEDIA_OFFSET_MULTIPLIER * (header.section_tables[i].media_end_offset -
                                                  header.section_tables[i].media_offset);
            auto dec =
                Decrypt(section, std::make_shared<OffsetVfsFile>(file, size, offset), offset);
            if (dec != nullptr) {
                auto npfs = std::make_shared<PartitionFilesystem>(std::move(dec));

                if (npfs->GetStatus() == Loader::ResultStatus::Success) {
                    dirs.push_back(std::move(npfs));
                    if (IsDirectoryExeFS(dirs.back()))
                        exefs = dirs.back();
                } else {
                    if (has_rights_id)
                        status = Loader::ResultStatus::ErrorIncorrectTitlekeyOrTitlekek;
                    else
                        status = Loader::ResultStatus::ErrorIncorrectKeyAreaKey;
                    return;
                }
            } else {
                if (status != Loader::ResultStatus::Success)
                    return;
                if (has_rights_id)
                    status = Loader::ResultStatus::ErrorIncorrectTitlekeyOrTitlekek;
                else
                    status = Loader::ResultStatus::ErrorIncorrectKeyAreaKey;
                return;
            }
        }
    }

    status = Loader::ResultStatus::Success;
}

Loader::ResultStatus NCA::GetStatus() const {
    return status;
}

std::vector<std::shared_ptr<VfsFile>> NCA::GetFiles() const {
    if (status != Loader::ResultStatus::Success)
        return {};
    return files;
}

std::vector<std::shared_ptr<VfsDirectory>> NCA::GetSubdirectories() const {
    if (status != Loader::ResultStatus::Success)
        return {};
    return dirs;
}

std::string NCA::GetName() const {
    return file->GetName();
}

std::shared_ptr<VfsDirectory> NCA::GetParentDirectory() const {
    return file->GetContainingDirectory();
}

NCAContentType NCA::GetType() const {
    return header.content_type;
}

u64 NCA::GetTitleId() const {
    if (is_update || status == Loader::ResultStatus::ErrorMissingBKTRBaseRomFS)
        return header.title_id | 0x800;
    return header.title_id;
}

bool NCA::IsUpdate() const {
    return is_update;
}

VirtualFile NCA::GetRomFS() const {
    return romfs;
}

VirtualDir NCA::GetExeFS() const {
    return exefs;
}

VirtualFile NCA::GetBaseFile() const {
    return file;
}

u64 NCA::GetBaseIVFCOffset() const {
    return ivfc_offset;
}

bool NCA::ReplaceFileWithSubdirectory(VirtualFile file, VirtualDir dir) {
    return false;
}
} // namespace FileSys