From 1efe5a76b11a5e7fd8071686acaf1b060e721aaa Mon Sep 17 00:00:00 2001
From: Zach Hilman <zachhilman@gmail.com>
Date: Sat, 25 Aug 2018 19:01:46 -0400
Subject: [PATCH] content_archive: Add BKTR header parsing to NCA
---
src/core/file_sys/content_archive.cpp | 171 +++++++++++++++++++++++---
src/core/file_sys/content_archive.h | 8 +-
2 files changed, 160 insertions(+), 19 deletions(-)
diff --git a/src/core/file_sys/content_archive.cpp b/src/core/file_sys/content_archive.cpp
index 7cfb6f36b6..f0d376bf52 100644
--- a/src/core/file_sys/content_archive.cpp
+++ b/src/core/file_sys/content_archive.cpp
@@ -12,6 +12,7 @@
#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"
@@ -68,10 +69,31 @@ struct RomFSSuperblock {
};
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.");
@@ -104,7 +126,7 @@ boost::optional<Core::Crypto::Key128> NCA::GetKeyAreaKey(NCASectionCryptoType ty
Core::Crypto::Key128 out;
if (type == NCASectionCryptoType::XTS)
std::copy(key_area.begin(), key_area.begin() + 0x10, out.begin());
- else if (type == NCASectionCryptoType::CTR)
+ 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}",
@@ -154,6 +176,9 @@ VirtualFile NCA::Decrypt(NCASectionHeader s_header, VirtualFile in, u64 starting
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;
@@ -190,7 +215,9 @@ VirtualFile NCA::Decrypt(NCASectionHeader s_header, VirtualFile in, u64 starting
}
}
-NCA::NCA(VirtualFile file_) : file(std::move(file_)) {
+NCA::NCA(VirtualFile file_, VirtualFile bktr_base_romfs_)
+ : file(std::move(file_)),
+ bktr_base_romfs(bktr_base_romfs_ ? std::move(bktr_base_romfs_) : nullptr) {
status = Loader::ResultStatus::Success;
if (file == nullptr) {
@@ -270,17 +297,15 @@ NCA::NCA(VirtualFile file_) : file(std::move(file_)) {
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;
const size_t romfs_offset =
- header.section_tables[i].media_offset * MEDIA_OFFSET_MULTIPLIER +
- section.romfs.ivfc.levels[IVFC_MAX_LEVEL - 1].offset;
+ base_offset + section.romfs.ivfc.levels[IVFC_MAX_LEVEL - 1].offset;
const size_t romfs_size = section.romfs.ivfc.levels[IVFC_MAX_LEVEL - 1].size;
- auto dec =
- Decrypt(section, std::make_shared<OffsetVfsFile>(file, romfs_size, romfs_offset),
- romfs_offset);
- if (dec != nullptr) {
- files.push_back(std::move(dec));
- romfs = files.back();
- } else {
+ 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)
@@ -289,6 +314,120 @@ NCA::NCA(VirtualFile file_) : file(std::move(file_)) {
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,
+ romfs_offset - base_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();
+ const u64 raw_size =
+ MEDIA_OFFSET_MULTIPLIER * (header.section_tables[i].media_end_offset -
+ header.section_tables[i].media_offset);
+ }
} else if (section.raw.header.filesystem_type == NCASectionFilesystemType::PFS0) {
u64 offset = (static_cast<u64>(header.section_tables[i].media_offset) *
MEDIA_OFFSET_MULTIPLIER) +
@@ -349,11 +488,17 @@ NCAContentType NCA::GetType() const {
}
u64 NCA::GetTitleId() const {
+ if (is_update || status == Loader::ResultStatus::ErrorMissingBKTRBaseRomFS)
+ return header.title_id | 0x800;
if (status != Loader::ResultStatus::Success)
return {};
return header.title_id;
}
+bool NCA::IsUpdate() const {
+ return is_update;
+}
+
VirtualFile NCA::GetRomFS() const {
return romfs;
}
@@ -366,10 +511,6 @@ VirtualFile NCA::GetBaseFile() const {
return file;
}
-bool NCA::IsUpdate() const {
- return is_update;
-}
-
bool NCA::ReplaceFileWithSubdirectory(VirtualFile file, VirtualDir dir) {
return false;
}
diff --git a/src/core/file_sys/content_archive.h b/src/core/file_sys/content_archive.h
index 0ea666cac4..104226f3a1 100644
--- a/src/core/file_sys/content_archive.h
+++ b/src/core/file_sys/content_archive.h
@@ -79,7 +79,7 @@ bool IsValidNCA(const NCAHeader& header);
// After construction, use GetStatus to determine if the file is valid and ready to be used.
class NCA : public ReadOnlyVfsDirectory {
public:
- explicit NCA(VirtualFile file);
+ explicit NCA(VirtualFile file, VirtualFile bktr_base_romfs = nullptr);
Loader::ResultStatus GetStatus() const;
std::vector<std::shared_ptr<VfsFile>> GetFiles() const override;
@@ -89,14 +89,13 @@ public:
NCAContentType GetType() const;
u64 GetTitleId() const;
+ bool IsUpdate() const;
VirtualFile GetRomFS() const;
VirtualDir GetExeFS() const;
VirtualFile GetBaseFile() const;
- bool IsUpdate() const;
-
protected:
bool ReplaceFileWithSubdirectory(VirtualFile file, VirtualDir dir) override;
@@ -112,14 +111,15 @@ private:
VirtualFile romfs = nullptr;
VirtualDir exefs = nullptr;
VirtualFile file;
+ VirtualFile bktr_base_romfs;
NCAHeader header{};
bool has_rights_id{};
- bool is_update{};
Loader::ResultStatus status{};
bool encrypted;
+ bool is_update;
Core::Crypto::KeyManager keys;
};
--
GitLab