add virtual filesystem with path sandboxing and quotas (milestone 7 complete)

sandbox-test/CMakeLists.txt

@@ -18,6 +18,7 @@ add_library(mosis-sandbox STATIC
     ../src/main/cpp/sandbox/timer_manager.cpp
     ../src/main/cpp/sandbox/json_api.cpp
     ../src/main/cpp/sandbox/crypto_api.cpp
+    ../src/main/cpp/sandbox/virtual_fs.cpp
 )
 target_include_directories(mosis-sandbox PUBLIC
     ../src/main/cpp/sandbox

sandbox-test/src/main.cpp

@@ -9,6 +9,7 @@
 #include "timer_manager.h"
 #include "json_api.h"
 #include "crypto_api.h"
+#include "virtual_fs.h"
 #include <filesystem>
 #include <fstream>
 #include <sstream>
@@ -1074,6 +1075,190 @@ bool Test_SecureMathRandom(std::string& error_msg) {
     return true;
 }
 
+//=============================================================================
+// MILESTONE 7: VIRTUAL FILESYSTEM TESTS
+//=============================================================================
+
+bool Test_VirtualFSReadWrite(std::string& error_msg) {
+    std::string test_root = "test_vfs_app";
+    mosis::VirtualFS vfs("test.app", test_root);
+
+    std::string err;
+
+    // Write a file
+    EXPECT_TRUE(vfs.Write("/data/test.txt", "Hello World", err));
+
+    // Read it back
+    auto content = vfs.Read("/data/test.txt", err);
+    EXPECT_TRUE(content.has_value());
+    EXPECT_TRUE(*content == "Hello World");
+
+    // Cleanup
+    vfs.ClearAll();
+    return true;
+}
+
+bool Test_VirtualFSBlocksTraversal(std::string& error_msg) {
+    std::string test_root = "test_vfs_app";
+    mosis::VirtualFS vfs("test.app", test_root);
+
+    std::string err;
+
+    // Should reject traversal
+    EXPECT_FALSE(vfs.Write("/data/../../../etc/passwd", "hack", err));
+    EXPECT_TRUE(err.find("traversal") != std::string::npos ||
+                err.find("invalid") != std::string::npos);
+
+    // Should reject paths without valid prefix
+    err.clear();
+    EXPECT_FALSE(vfs.Write("/etc/passwd", "hack", err));
+
+    vfs.ClearAll();
+    return true;
+}
+
+bool Test_VirtualFSEnforcesQuota(std::string& error_msg) {
+    std::string test_root = "test_vfs_app";
+    mosis::VirtualFSLimits limits;
+    limits.max_quota_bytes = 1024;  // 1 KB quota for testing
+    mosis::VirtualFS vfs("test.app", test_root, limits);
+
+    std::string err;
+
+    // Write should succeed
+    std::string small_data(500, 'a');
+    EXPECT_TRUE(vfs.Write("/data/file1.txt", small_data, err));
+
+    // Second write should fail (exceeds quota)
+    std::string large_data(600, 'b');
+    EXPECT_FALSE(vfs.Write("/data/file2.txt", large_data, err));
+    EXPECT_TRUE(err.find("quota") != std::string::npos);
+
+    vfs.ClearAll();
+    return true;
+}
+
+bool Test_VirtualFSCleansUpTemp(std::string& error_msg) {
+    std::string test_root = "test_vfs_app";
+    mosis::VirtualFS vfs("test.app", test_root);
+
+    std::string err;
+
+    // Write to temp
+    EXPECT_TRUE(vfs.Write("/temp/session.txt", "temp data", err));
+    EXPECT_TRUE(vfs.Exists("/temp/session.txt"));
+
+    // Clear temp
+    vfs.ClearTemp();
+
+    // Should be gone
+    EXPECT_FALSE(vfs.Exists("/temp/session.txt"));
+
+    vfs.ClearAll();
+    return true;
+}
+
+bool Test_VirtualFSList(std::string& error_msg) {
+    std::string test_root = "test_vfs_app";
+    mosis::VirtualFS vfs("test.app", test_root);
+
+    std::string err;
+
+    // Create some files
+    vfs.Write("/data/file1.txt", "content1", err);
+    vfs.Write("/data/file2.txt", "content2", err);
+    vfs.MakeDir("/data/subdir", err);
+
+    // List directory
+    auto files = vfs.List("/data/", err);
+    EXPECT_TRUE(files.has_value());
+    EXPECT_TRUE(files->size() == 3);
+
+    vfs.ClearAll();
+    return true;
+}
+
+bool Test_VirtualFSStat(std::string& error_msg) {
+    std::string test_root = "test_vfs_app";
+    mosis::VirtualFS vfs("test.app", test_root);
+
+    std::string err;
+
+    // Write a file
+    vfs.Write("/data/test.txt", "Hello", err);
+
+    // Get stat
+    auto stat = vfs.Stat("/data/test.txt", err);
+    EXPECT_TRUE(stat.has_value());
+    EXPECT_TRUE(stat->size == 5);
+    EXPECT_FALSE(stat->is_dir);
+
+    // Directory stat
+    vfs.MakeDir("/data/subdir", err);
+    auto dir_stat = vfs.Stat("/data/subdir", err);
+    EXPECT_TRUE(dir_stat.has_value());
+    EXPECT_TRUE(dir_stat->is_dir);
+
+    vfs.ClearAll();
+    return true;
+}
+
+bool Test_VirtualFSLuaIntegration(std::string& error_msg) {
+    SandboxContext ctx = TestContext();
+    LuaSandbox sandbox(ctx);
+
+    std::string test_root = "test_vfs_lua";
+    mosis::VirtualFS vfs("test.app", test_root);
+    mosis::RegisterVirtualFS(sandbox.GetState(), &vfs);
+
+    std::string script = R"(
+        -- Write and read
+        local ok, err = fs.write("/data/test.txt", "Hello from Lua")
+        assert(ok, "write failed: " .. (err or ""))
+
+        local content, err = fs.read("/data/test.txt")
+        assert(content == "Hello from Lua", "content mismatch: " .. (content or "nil"))
+
+        -- Check exists
+        assert(fs.exists("/data/test.txt"), "file should exist")
+        assert(not fs.exists("/data/nonexistent.txt"), "file should not exist")
+
+        -- Stat
+        local stat = fs.stat("/data/test.txt")
+        assert(stat.size == 14, "size should be 14, got " .. tostring(stat.size))
+        assert(not stat.isDir, "should not be dir")
+    )";
+
+    bool ok = sandbox.LoadString(script, "vfs_test");
+    vfs.ClearAll();
+
+    if (!ok) {
+        error_msg = "Lua test failed: " + sandbox.GetLastError();
+        return false;
+    }
+    return true;
+}
+
+bool Test_VirtualFSMaxFileSize(std::string& error_msg) {
+    std::string test_root = "test_vfs_app";
+    mosis::VirtualFSLimits limits;
+    limits.max_file_size = 100;  // 100 bytes max
+    limits.max_quota_bytes = 10000;  // Large quota
+    mosis::VirtualFS vfs("test.app", test_root, limits);
+
+    std::string err;
+
+    // Small file should succeed
+    EXPECT_TRUE(vfs.Write("/data/small.txt", std::string(50, 'a'), err));
+
+    // Large file should fail
+    EXPECT_FALSE(vfs.Write("/data/large.txt", std::string(200, 'b'), err));
+    EXPECT_TRUE(err.find("size") != std::string::npos);
+
+    vfs.ClearAll();
+    return true;
+}
+
 //=============================================================================
 // MAIN
 //=============================================================================
@@ -1176,6 +1361,16 @@ int main(int argc, char* argv[]) {
     harness.AddTest("CryptoHMAC", Test_CryptoHMAC);
     harness.AddTest("SecureMathRandom", Test_SecureMathRandom);
 
+    // Milestone 7: Virtual Filesystem
+    harness.AddTest("VirtualFSReadWrite", Test_VirtualFSReadWrite);
+    harness.AddTest("VirtualFSBlocksTraversal", Test_VirtualFSBlocksTraversal);
+    harness.AddTest("VirtualFSEnforcesQuota", Test_VirtualFSEnforcesQuota);
+    harness.AddTest("VirtualFSCleansUpTemp", Test_VirtualFSCleansUpTemp);
+    harness.AddTest("VirtualFSList", Test_VirtualFSList);
+    harness.AddTest("VirtualFSStat", Test_VirtualFSStat);
+    harness.AddTest("VirtualFSLuaIntegration", Test_VirtualFSLuaIntegration);
+    harness.AddTest("VirtualFSMaxFileSize", Test_VirtualFSMaxFileSize);
+
     // Run tests
     auto results = harness.Run(filter);