sysupdater: implement content meta mounting

libraries/libstratosphere/include/stratosphere/fs.hpp

@@ -24,6 +24,7 @@
 #include <stratosphere/fs/fsa/fs_registrar.hpp>
 #include <stratosphere/fs/fs_remote_filesystem.hpp>
 #include <stratosphere/fs/fs_read_only_filesystem.hpp>
+#include <stratosphere/fs/fs_shared_filesystem_holder.hpp>
 #include <stratosphere/fs/fs_istorage.hpp>
 #include <stratosphere/fs/fs_substorage.hpp>
 #include <stratosphere/fs/fs_memory_storage.hpp>

libraries/libstratosphere/include/stratosphere/fs/fs_shared_filesystem_holder.hpp

@@ -0,0 +1,54 @@
+/*
+ * Copyright (c) 2018-2020 Atmosphère-NX
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#pragma once
+#include <stratosphere/fs/fs_common.hpp>
+#include <stratosphere/fs/impl/fs_newable.hpp>
+#include <stratosphere/fs/fsa/fs_ifile.hpp>
+#include <stratosphere/fs/fsa/fs_idirectory.hpp>
+#include <stratosphere/fs/fsa/fs_ifilesystem.hpp>
+
+namespace ams::fs {
+
+    class SharedFileSystemHolder : public fsa::IFileSystem, public impl::Newable {
+        NON_COPYABLE(SharedFileSystemHolder);
+        NON_MOVEABLE(SharedFileSystemHolder);
+        private:
+            std::shared_ptr<fsa::IFileSystem> fs;
+        public:
+            SharedFileSystemHolder(std::shared_ptr<fsa::IFileSystem> f) : fs(std::move(f)) { /* ... */ }
+        public:
+            virtual Result CreateFileImpl(const char *path, s64 size, int flags) override { return this->fs->CreateFile(path, size, flags); }
+            virtual Result DeleteFileImpl(const char *path) override { return this->fs->DeleteFile(path); }
+            virtual Result CreateDirectoryImpl(const char *path) override { return this->fs->CreateDirectory(path); }
+            virtual Result DeleteDirectoryImpl(const char *path) override { return this->fs->DeleteDirectory(path); }
+            virtual Result DeleteDirectoryRecursivelyImpl(const char *path) override { return this->fs->DeleteDirectoryRecursively(path); }
+            virtual Result RenameFileImpl(const char *old_path, const char *new_path) override { return this->fs->RenameFile(old_path, new_path); }
+            virtual Result RenameDirectoryImpl(const char *old_path, const char *new_path) override { return this->fs->RenameDirectory(old_path, new_path); }
+            virtual Result GetEntryTypeImpl(fs::DirectoryEntryType *out, const char *path) override { return this->fs->GetEntryType(out, path); }
+            virtual Result OpenFileImpl(std::unique_ptr<fs::fsa::IFile> *out_file, const char *path, fs::OpenMode mode) override { return this->fs->OpenFile(out_file, path, mode); }
+            virtual Result OpenDirectoryImpl(std::unique_ptr<fs::fsa::IDirectory> *out_dir, const char *path, fs::OpenDirectoryMode mode) override { return this->fs->OpenDirectory(out_dir, path, mode); }
+            virtual Result CommitImpl() override { return this->fs->Commit(); }
+            virtual Result GetFreeSpaceSizeImpl(s64 *out, const char *path) override { return this->fs->GetFreeSpaceSize(out, path); }
+            virtual Result GetTotalSpaceSizeImpl(s64 *out, const char *path) override { return this->fs->GetTotalSpaceSize(out, path); }
+            virtual Result CleanDirectoryRecursivelyImpl(const char *path) override { return this->fs->CleanDirectoryRecursively(path); }
+
+            /* These aren't accessible as commands. */
+            virtual Result CommitProvisionallyImpl(s64 counter) override { return this->fs->CommitProvisionally(counter); }
+            virtual Result RollbackImpl() override { return this->fs->Rollback(); }
+            virtual Result FlushImpl() override { return this->fs->Flush(); }
+    };
+
+}

libraries/libvapours/include/vapours/results/fs_results.hpp

@@ -78,6 +78,8 @@ namespace ams::fs {
         R_DEFINE_ERROR_RESULT(AllocationFailureInRomFsFileSystemA,              3247);
         R_DEFINE_ERROR_RESULT(AllocationFailureInRomFsFileSystemB,              3248);
         R_DEFINE_ERROR_RESULT(AllocationFailureInRomFsFileSystemC,              3249);
+        R_DEFINE_ERROR_RESULT(AllocationFailureInFileSystemProxyCoreImplD,      3256);
+        R_DEFINE_ERROR_RESULT(AllocationFailureInFileSystemProxyCoreImplE,      3257);
         R_DEFINE_ERROR_RESULT(AllocationFailureInPartitionFileSystemCreatorA,   3280);
         R_DEFINE_ERROR_RESULT(AllocationFailureInRomFileSystemCreatorA,         3281);
         R_DEFINE_ERROR_RESULT(AllocationFailureInStorageOnNcaCreatorA,          3288);

libraries/libvapours/include/vapours/util/util_string_util.hpp

@@ -20,6 +20,54 @@
 
 namespace ams::util {
 
+    template<typename T>
+    constexpr T ToLower(T c) {
+        return ('A' <= c && c <= 'Z') ? (c - 'A' + 'a') : c;
+    }
+
+    template<typename T>
+    constexpr T ToUpper(T c) {
+        return ('a' <= c && c <= 'z') ? (c - 'a' + 'A') : c;
+    }
+
+    template<typename T>
+    int Strncmp(const T *lhs, const T *rhs, int count) {
+        AMS_ASSERT(lhs != nullptr);
+        AMS_ASSERT(rhs != nullptr);
+        AMS_ABORT_UNLESS(count >= 0);
+
+        if (count == 0) {
+            return 0;
+        }
+
+        T l, r;
+        do {
+            l = *(lhs++);
+            r = *(rhs++);
+        } while (l && (l == r) && (--count));
+
+        return l - r;
+    }
+
+    template<typename T>
+    int Strnicmp(const T *lhs, const T *rhs, int count) {
+        AMS_ASSERT(lhs != nullptr);
+        AMS_ASSERT(rhs != nullptr);
+        AMS_ABORT_UNLESS(count >= 0);
+
+        if (count == 0) {
+            return 0;
+        }
+
+        T l, r;
+        do {
+            l = ::ams::util::ToLower(*(lhs++));
+            r = ::ams::util::ToLower(*(rhs++));
+        } while (l && (l == r) && (--count));
+
+        return l - r;
+    }
+
     template<typename T>
     constexpr int Strlcpy(T *dst, const T *src, int count) {
         AMS_ASSERT(dst != nullptr);

stratosphere/ams_mitm/source/amsmitm_main.cpp

@@ -88,8 +88,8 @@ void __appInit(void) {
     /* Initialize fssystem library. */
     fssystem::InitializeForFileSystemProxy();
 
-    /* Configure ncm to use fssystem library to mount content. */
+    /* Configure ncm to use fssystem library to mount content from the sd card. */
-    ncm::SetMountContentMetaFunction(mitm::sysupdater::MountContentMeta);
+    ncm::SetMountContentMetaFunction(mitm::sysupdater::MountSdCardContentMeta);
 
     ams::CheckApiVersion();
 }

stratosphere/ams_mitm/source/sysupdater/sysupdater_fs_utils.cpp

@@ -18,9 +18,203 @@
 
 namespace ams::mitm::sysupdater {
 
-    Result MountContentMeta(const char *mount_name, const char *path) {
+    namespace {
-        /* TODO: Implement */
+
-        AMS_ABORT();
+        constexpr inline const char * const NcaExtension = ".nca";
+        constexpr inline const char * const NspExtension = ".nsp";
+        constexpr inline const size_t NcaExtensionSize = 4;
+        constexpr inline const size_t NspExtensionSize = 4;
+
+        static_assert(NcaExtensionSize == NspExtensionSize);
+        constexpr inline const size_t NcaNspExtensionSize = NcaExtensionSize;
+
+        constexpr inline std::underlying_type<fssrv::PathNormalizer::Option>::type SdCardContentMetaPathNormalizeOption = fssrv::PathNormalizer::Option_PreserveTailSeparator |
+                                                                                                                          fssrv::PathNormalizer::Option_HasMountName;
+
+        Result CheckNcaOrNsp(const char **path) {
+            /* Ensure that the path is currently at the mount name delimeter. */
+            R_UNLESS(std::strncmp(*path, ams::fs::impl::MountNameDelimiter, strnlen(ams::fs::impl::MountNameDelimiter, ams::fs::EntryNameLengthMax)) == 0, fs::ResultPathNotFound());
+
+            /* Advance past the :. */
+            static_assert(ams::fs::impl::MountNameDelimiter[0] == ':');
+            *path += 1;
+
+            /* Ensure path is long enough for the extension. */
+            const auto path_len = strnlen(*path, ams::fs::EntryNameLengthMax);
+            R_UNLESS(path_len > NcaNspExtensionSize, fs::ResultPathNotFound());
+
+            /* Get the extension. */
+            const char * const extension = *path + path_len - NcaNspExtensionSize;
+
+            /* Ensure nca or nsp. */
+            const bool is_nca = util::Strnicmp(extension, NcaExtension, NcaNspExtensionSize) == 0;
+            const bool is_nsp = util::Strnicmp(extension, NspExtension, NcaNspExtensionSize) == 0;
+            R_UNLESS(is_nca || is_nsp, fs::ResultPathNotFound());
+
+            return ResultSuccess();
+        }
+
+        Result ParseMountName(const char **path, std::shared_ptr<ams::fs::fsa::IFileSystem> *out) {
+            /* The equivalent function here supports all the common mount names; we'll only support the SD card. */
+            if (const auto sd_mount_len = strnlen(ams::fs::impl::SdCardFileSystemMountName, ams::fs::MountNameLengthMax); std::strncmp(*path, ams::fs::impl::SdCardFileSystemMountName, sd_mount_len) == 0) {
+                /* Open an sd card fs. */
+                *path += sd_mount_len;
+
+                /* Open the SD card. This uses libnx bindings. */
+                FsFileSystem fs;
+                R_TRY(fsOpenSdCardFileSystem(std::addressof(fs)));
+
+                /* Allocate a new filesystem wrapper. */
+                auto fsa = std::make_shared<ams::fs::RemoteFileSystem>(fs);
+                R_UNLESS(fsa != nullptr, fs::ResultAllocationFailureInSdCardA());
+
+                /* Set the output fs. */
+                *out = std::move(fsa);
+            } else {
+                return fs::ResultPathNotFound();
+            }
+
+            /* Ensure that there's something that could be a mount name delimiter. */
+            R_UNLESS(strnlen(*path, fs::EntryNameLengthMax) != 0, fs::ResultPathNotFound());
+
+            return ResultSuccess();
+        }
+
+        Result ParseNsp(const char **path, std::shared_ptr<ams::fs::fsa::IFileSystem> *out, std::shared_ptr<ams::fs::fsa::IFileSystem> base_fs) {
+            const char *work_path = *path;
+
+            /* Advance to the nsp extension. */
+            while (true) {
+                if (util::Strnicmp(work_path, NspExtension, NspExtensionSize) == 0) {
+                    if (work_path[NspExtensionSize] == '\x00' || work_path[NspExtensionSize] == '/') {
+                        break;
+                    }
+                    work_path += NspExtensionSize;
+                } else {
+                    R_UNLESS(*work_path != '\x00', fs::ResultPathNotFound());
+
+                    work_path += 1;
+                }
+            }
+
+            /* Advance past the extension. */
+            work_path += NspExtensionSize;
+
+            /* Get the nsp path. */
+            char nsp_path[fs::EntryNameLengthMax + 1];
+            R_UNLESS(static_cast<size_t>(work_path - *path) <= sizeof(nsp_path), fs::ResultTooLongPath());
+            std::memcpy(nsp_path, *path, work_path - *path);
+            nsp_path[work_path - *path] = '\x00';
+
+            /* Open the file storage. */
+            std::shared_ptr<ams::fs::FileStorageBasedFileSystem> file_storage = fssystem::AllocateShared<ams::fs::FileStorageBasedFileSystem>();
+            R_UNLESS(file_storage != nullptr, fs::ResultAllocationFailureInFileSystemProxyCoreImplD());
+            R_TRY(file_storage->Initialize(std::move(base_fs), nsp_path, ams::fs::OpenMode_Read));
+
+            /* Create a partition fs. */
+            R_TRY(fssystem::GetFileSystemCreatorInterfaces()->partition_fs_creator->Create(out, std::move(file_storage)));
+
+            /* Update the path. */
+            *path = work_path;
+
+            return ResultSuccess();
+        }
+
+        Result ParseNca(const char **path, std::shared_ptr<fssystem::NcaReader> *out, std::shared_ptr<ams::fs::fsa::IFileSystem> base_fs) {
+            /* Open the file storage. */
+            std::shared_ptr<ams::fs::FileStorageBasedFileSystem> file_storage = fssystem::AllocateShared<ams::fs::FileStorageBasedFileSystem>();
+            R_UNLESS(file_storage != nullptr, fs::ResultAllocationFailureInFileSystemProxyCoreImplE());
+            R_TRY(file_storage->Initialize(std::move(base_fs), *path, ams::fs::OpenMode_Read));
+
+            /* Create the nca reader. */
+            std::shared_ptr<fssystem::NcaReader> nca_reader;
+            R_TRY(fssystem::GetFileSystemCreatorInterfaces()->storage_on_nca_creator->CreateNcaReader(std::addressof(nca_reader), file_storage));
+
+            /* NOTE: Here Nintendo validates program ID, but this does not need checking in the meta case. */
+
+            /* Set output reader. */
+            *out = std::move(nca_reader);
+            return ResultSuccess();
+        }
+
+        Result OpenMetaStorage(std::shared_ptr<ams::fs::IStorage> *out, std::shared_ptr<fssystem::NcaReader> nca_reader, fssystem::NcaFsHeader::FsType *out_fs_type) {
+            /* Ensure the nca is a meta nca. */
+            R_UNLESS(nca_reader->GetContentType() == fssystem::NcaHeader::ContentType::Meta, fs::ResultPreconditionViolation());
+
+            /* We only support SD card ncas, so ensure this isn't a gamecard nca. */
+            R_UNLESS(nca_reader->GetDistributionType() != fssystem::NcaHeader::DistributionType::GameCard, fs::ResultPermissionDenied());
+
+            /* Here Nintendo would call GetPartitionIndex(), but we don't need to, because it's meta. */
+            constexpr int MetaPartitionIndex = 0;
+
+            /* Open fs header reader. */
+            fssystem::NcaFsHeaderReader fs_header_reader;
+            R_TRY(fssystem::GetFileSystemCreatorInterfaces()->storage_on_nca_creator->Create(out, std::addressof(fs_header_reader), std::move(nca_reader), MetaPartitionIndex, false));
+
+            /* Set the output fs type. */
+            *out_fs_type = fs_header_reader.GetFsType();
+            return ResultSuccess();
+        }
+
+        Result OpenContentMetaFileSystem(std::shared_ptr<ams::fs::fsa::IFileSystem> *out, const char *path) {
+            /* Parse the mount name to get a filesystem. */
+            const char *cur_path = path;
+            std::shared_ptr<ams::fs::fsa::IFileSystem> base_fs;
+            R_TRY(ParseMountName(std::addressof(cur_path), std::addressof(base_fs)));
+
+            /* Ensure the path is an nca or nsp. */
+            R_TRY(CheckNcaOrNsp(std::addressof(cur_path)));
+
+            /* Try to parse as nsp. */
+            std::shared_ptr<ams::fs::fsa::IFileSystem> nsp_fs;
+            if (R_SUCCEEDED(ParseNsp(std::addressof(cur_path), std::addressof(nsp_fs), base_fs))) {
+                /* nsp target is only allowed for type package, and we're assuming type meta. */
+                R_UNLESS(*path != '\x00', fs::ResultInvalidArgument());
+
+                /* Use the nsp fs as the base fs. */
+                base_fs = std::move(nsp_fs);
+            }
+
+            /* Parse as nca. */
+            std::shared_ptr<fssystem::NcaReader> nca_reader;
+            R_TRY(ParseNca(std::addressof(cur_path), std::addressof(nca_reader), std::move(base_fs)));
+
+            /* Open meta storage. */
+            std::shared_ptr<ams::fs::IStorage> storage;
+            fssystem::NcaFsHeader::FsType fs_type;
+            R_TRY(OpenMetaStorage(std::addressof(storage), std::move(nca_reader), std::addressof(fs_type)));
+
+            /* Open the appropriate interface. */
+            const auto * const creator_intfs = fssystem::GetFileSystemCreatorInterfaces();
+            switch (fs_type) {
+                case fssystem::NcaFsHeader::FsType::PartitionFs: return creator_intfs->partition_fs_creator->Create(out, std::move(storage));
+                case fssystem::NcaFsHeader::FsType::RomFs:       return creator_intfs->rom_fs_creator->Create(out, std::move(storage));
+                default:
+                    return fs::ResultInvalidNcaFileSystemType();
+            }
+        }
+
+    }
+
+    Result MountSdCardContentMeta(const char *mount_name, const char *path) {
+        /* Sanitize input. */
+        /* NOTE: This is an internal API, so we won't bother with mount name sanitization. */
+        R_UNLESS(path != nullptr, fs::ResultInvalidPath());
+
+        /* Normalize the path. */
+        fssrv::PathNormalizer normalized_path(path, SdCardContentMetaPathNormalizeOption);
+        R_TRY(normalized_path.GetResult());
+
+        /* Open the filesystem. */
+        std::shared_ptr<ams::fs::fsa::IFileSystem> fs;
+        R_TRY(OpenContentMetaFileSystem(std::addressof(fs), normalized_path.GetPath()));
+
+        /* Create a holder for the fs. */
+        std::unique_ptr unique_fs = std::make_unique<ams::fs::SharedFileSystemHolder>(std::move(fs));
+        R_UNLESS(unique_fs != nullptr, fs::ResultAllocationFailureInNew());
+
+        /* Register the fs. */
+        return ams::fs::fsa::Register(mount_name, std::move(unique_fs));
     }
 
 }

stratosphere/ams_mitm/source/sysupdater/sysupdater_fs_utils.hpp

@@ -18,6 +18,6 @@
 
 namespace ams::mitm::sysupdater {
 
-    Result MountContentMeta(const char *mount_name, const char *path);
+    Result MountSdCardContentMeta(const char *mount_name, const char *path);
 
 }