OpenBSD: add FFS volume formatting support

Expose FFS as the native OpenBSD filesystem option for volume creation and accept FFS/UFS on the command line, mapping mounts to the OpenBSD ffs filesystem type.

Run newfs through the elevated core service on vnd raw devices, then temporarily mount the new filesystem to transfer root directory ownership back to the invoking user.

Keep the non-interactive creation default as FAT on OpenBSD so existing unattended scripts do not start requiring elevation.

src/Core/Unix/CoreService.cpp

@@ -914,6 +914,168 @@ namespace VeraCrypt
 	}
 #endif
 
+#ifdef TC_OPENBSD
+	static bool ParseOpenBSDVndDevicePath (const string &path, bool rawDevice, string &deviceNumber)
+	{
+		const string prefix = rawDevice ? "/dev/rvnd" : "/dev/vnd";
+		if (path.find (prefix) != 0)
+			return false;
+
+		size_t numberStart = prefix.size();
+		size_t numberEnd = numberStart;
+		while (numberEnd < path.size() && path[numberEnd] >= '0' && path[numberEnd] <= '9')
+			++numberEnd;
+
+		if (numberEnd == numberStart)
+			return false;
+
+		if (numberEnd + 1 != path.size() || path[numberEnd] != 'c')
+			return false;
+
+		deviceNumber = path.substr (numberStart, numberEnd - numberStart);
+		return true;
+	}
+
+	static string GetOpenBSDVndBlockDevicePath (const DevicePath &rawDevice)
+	{
+		string deviceNumber;
+		if (!ParseOpenBSDVndDevicePath (string (rawDevice), true, deviceNumber))
+			throw ParameterIncorrect (SRC_POS);
+
+		return string ("/dev/vnd") + deviceNumber + "c";
+	}
+
+	static void ValidateOpenBSDVndDeviceNode (const string &path, bool rawDevice)
+	{
+		string deviceNumber;
+		if (!ParseOpenBSDVndDevicePath (path, rawDevice, deviceNumber))
+			throw ParameterIncorrect (SRC_POS);
+
+		struct stat sb;
+		if (lstat (path.c_str(), &sb) != 0)
+			throw ParameterIncorrect (SRC_POS);
+
+		if (rawDevice)
+		{
+			if (!S_ISCHR (sb.st_mode))
+				throw ParameterIncorrect (SRC_POS);
+		}
+		else if (!S_ISBLK (sb.st_mode))
+			throw ParameterIncorrect (SRC_POS);
+	}
+
+	static void ValidateOpenBSDFFSFormatterRequest (const ExecuteOpenBSDFFSFormatterRequest &request)
+	{
+		ValidateOpenBSDVndDeviceNode (string (request.Device), true);
+		ValidateOpenBSDVndDeviceNode (GetOpenBSDVndBlockDevicePath (request.Device), false);
+
+		if (request.OwnerUserId > static_cast <uint64> ((uid_t) -1)
+			|| request.OwnerGroupId > static_cast <uint64> ((gid_t) -1))
+		{
+			throw ParameterIncorrect (SRC_POS);
+		}
+	}
+
+	static list <string> BuildOpenBSDFFSFormatterArguments (const ExecuteOpenBSDFFSFormatterRequest &request)
+	{
+		ValidateOpenBSDFFSFormatterRequest (request);
+
+		list <string> arguments;
+		arguments.push_back (string (request.Device));
+		return arguments;
+	}
+
+	static DirectoryPath CreateOpenBSDFFSTemporaryMountPoint ()
+	{
+		string mountPointTemplate = "/tmp/veracrypt-ffs.XXXXXXXXXX";
+		vector <char> mountPoint (mountPointTemplate.begin(), mountPointTemplate.end());
+		mountPoint.push_back ('\0');
+
+		char *createdPath = mkdtemp (&mountPoint.front());
+		throw_sys_sub_if (!createdPath, mountPointTemplate);
+
+		return DirectoryPath (createdPath);
+	}
+
+	static void RemoveOpenBSDFFSTemporaryMountPoint (const DirectoryPath &mountPoint)
+	{
+		if (!mountPoint.IsEmpty())
+			rmdir (string (mountPoint).c_str());
+	}
+
+	static void MountOpenBSDFFSTemporaryFilesystem (const DevicePath &devicePath, const DirectoryPath &mountPoint)
+	{
+		list <string> args;
+		args.push_back ("-t");
+		args.push_back ("ffs");
+		args.push_back ("-o");
+		args.push_back ("nodev,nosuid,noexec");
+		args.push_back ("--");
+		args.push_back (devicePath);
+		args.push_back (mountPoint);
+
+		Process::Execute ("mount", args);
+	}
+
+	static void DismountOpenBSDFFSTemporaryFilesystem (const DirectoryPath &mountPoint)
+	{
+		list <string> args;
+		args.push_back ("--");
+		args.push_back (mountPoint);
+
+		for (int attempt = 0; true; ++attempt)
+		{
+			try
+			{
+				Process::Execute ("umount", args);
+				return;
+			}
+			catch (ExecutedProcessFailed&)
+			{
+				if (attempt >= 5)
+					throw;
+				Thread::Sleep (200);
+			}
+		}
+	}
+
+	static void SetOpenBSDFFSRootOwner (const ExecuteOpenBSDFFSFormatterRequest &request)
+	{
+		ValidateOpenBSDFFSFormatterRequest (request);
+
+		DirectoryPath mountPoint = CreateOpenBSDFFSTemporaryMountPoint();
+		bool mounted = false;
+
+		try
+		{
+			MountOpenBSDFFSTemporaryFilesystem (DevicePath (GetOpenBSDVndBlockDevicePath (request.Device)), mountPoint);
+			mounted = true;
+
+			string mountPointStr = mountPoint;
+			throw_sys_sub_if (chown (mountPointStr.c_str(), static_cast <uid_t> (request.OwnerUserId), static_cast <gid_t> (request.OwnerGroupId)) == -1, mountPointStr);
+
+			DismountOpenBSDFFSTemporaryFilesystem (mountPoint);
+			mounted = false;
+
+			throw_sys_sub_if (rmdir (mountPointStr.c_str()) == -1, mountPointStr);
+		}
+		catch (...)
+		{
+			if (mounted)
+			{
+				try
+				{
+					DismountOpenBSDFFSTemporaryFilesystem (mountPoint);
+				}
+				catch (...) { }
+			}
+
+			RemoveOpenBSDFFSTemporaryMountPoint (mountPoint);
+			throw;
+		}
+	}
+#endif
+
 	unique_ptr <Serializable> CoreService::GetResponseObject ()
 	{
 		unique_ptr <Serializable> deserializedObject (Serializable::DeserializeNew (ServiceOutputStream));
@@ -1131,6 +1293,18 @@ namespace VeraCrypt
 					}
 #endif
 
+#ifdef TC_OPENBSD
+					// ExecuteOpenBSDFFSFormatterRequest
+					ExecuteOpenBSDFFSFormatterRequest *executeFFSFormatterRequest = dynamic_cast <ExecuteOpenBSDFFSFormatterRequest*> (request.get());
+					if (executeFFSFormatterRequest)
+					{
+						Process::Execute (CoreService::GetOpenBSDFFSFormatterPath(), BuildOpenBSDFFSFormatterArguments (*executeFFSFormatterRequest));
+						SetOpenBSDFFSRootOwner (*executeFFSFormatterRequest);
+						ExecuteOpenBSDFFSFormatterResponse().Serialize (outputStream);
+						continue;
+					}
+#endif
+
 					// MountVolumeRequest
 					MountVolumeRequest *mountRequest = dynamic_cast <MountVolumeRequest*> (request.get());
 					if (mountRequest)
@@ -1237,6 +1411,19 @@ namespace VeraCrypt
 	}
 #endif
 
+#ifdef TC_OPENBSD
+	const char *CoreService::GetOpenBSDFFSFormatterPath ()
+	{
+		return "/sbin/newfs";
+	}
+
+	void CoreService::RequestExecuteOpenBSDFFSFormatter (const DevicePath &devicePath, uint64 userId, uint64 groupId)
+	{
+		ExecuteOpenBSDFFSFormatterRequest request (devicePath, userId, groupId);
+		SendRequest <ExecuteOpenBSDFFSFormatterResponse> (request);
+	}
+#endif
+
 	shared_ptr <VolumeInfo> CoreService::RequestMountVolume (MountOptions &options)
 	{
 		MountVolumeRequest request (&options);