launch_daemon: Now blocks the CD tray on read-only /boot.

src/servers/launch/Conditions.cpp

@@ -13,9 +13,7 @@
 #include <Message.h>
 #include <StringList.h>
 
-#include <DiskDevice.h>
-#include <DiskDeviceRoster.h>
-#include <Volume.h>
+#include "Utility.h"
 
 
 class ConditionContainer : public Condition {
@@ -86,7 +84,9 @@ public:
 	virtual	BString				ToString() const;
 
 private:
-			dev_t				fDevice;
+			BString				fPath;
+	mutable	bool				fIsReadOnly;
+	mutable	bool				fTestPerformed;
 };
 
 
@@ -365,33 +365,28 @@ SafeModeCondition::ToString() const
 
 
 ReadOnlyCondition::ReadOnlyCondition(const BMessage& args)
+	:
+	fPath(args.GetString("args")),
+	fIsReadOnly(false),
+	fTestPerformed(false)
 {
-	fDevice = dev_for_path(args.GetString("args", "/boot"));
 }
 
 
 bool
 ReadOnlyCondition::Test(ConditionContext& context) const
 {
-	BVolume volume;
-	status_t status = volume.SetTo(fDevice);
-	if (status != B_OK) {
-		fprintf(stderr, "Failed to get BVolume for device %" B_PRIdDEV
-			": %s\n", fDevice, strerror(status));
-		return false;
-	}
+	if (fTestPerformed)
+		return fIsReadOnly;
 
-	BDiskDeviceRoster roster;
-	BDiskDevice diskDevice;
-	BPartition* partition;
-	status = roster.FindPartitionByVolume(volume, &diskDevice, &partition);
-	if (status != B_OK) {
-		fprintf(stderr, "Failed to get partition for device %" B_PRIdDEV
-			": %s\n", fDevice, strerror(status));
-		return false;
-	}
+	if (fPath.IsEmpty() || fPath == "/boot")
+		fIsReadOnly = context.BootVolumeIsReadOnly();
+	else
+		fIsReadOnly = Utility::IsReadOnlyVolume(fPath);
 
-	return partition->IsReadOnly();
+	fTestPerformed = true;
+
+	return fIsReadOnly;
 }
 
 
@@ -406,7 +401,7 @@ BString
 ReadOnlyCondition::ToString() const
 {
 	BString string = "readonly ";
-	string << fDevice;
+	string << fPath;
 	return string;
 }
 

src/servers/launch/Conditions.h

@@ -15,6 +15,7 @@ class BMessage;
 class ConditionContext {
 public:
 	virtual	bool				IsSafeMode() const = 0;
+	virtual	bool				BootVolumeIsReadOnly() const = 0;
 };
 
 

src/servers/launch/Jamfile

@@ -14,6 +14,7 @@ Server launch_daemon
 	Job.cpp
 	SettingsParser.cpp
 	Target.cpp
+	Utility.cpp
 	Worker.cpp
 
 	# init jobs

src/servers/launch/LaunchDaemon.cpp

@@ -37,6 +37,7 @@
 #include "Job.h"
 #include "SettingsParser.h"
 #include "Target.h"
+#include "Utility.h"
 #include "Worker.h"
 
 
@@ -78,6 +79,7 @@ public:
 			Session*			FindSession(uid_t user) const;
 
 	virtual	bool				IsSafeMode() const;
+	virtual	bool				BootVolumeIsReadOnly() const;
 
 	virtual	void				ReadyToRun();
 	virtual	void				MessageReceived(BMessage* message);
@@ -123,6 +125,7 @@ private:
 			MainWorker*			fMainWorker;
 			Target*				fInitTarget;
 			bool				fSafeMode;
+			bool				fReadOnlyBootVolume;
 			bool				fUserMode;
 };
 
@@ -221,11 +224,23 @@ LaunchDaemon::IsSafeMode() const
 }
 
 
+bool
+LaunchDaemon::BootVolumeIsReadOnly() const
+{
+	return fReadOnlyBootVolume;
+}
+
+
 void
 LaunchDaemon::ReadyToRun()
 {
 	_RetrieveKernelOptions();
 	_SetupEnvironment();
+
+	fReadOnlyBootVolume = Utility::IsReadOnlyVolume("/boot");
+	if (fReadOnlyBootVolume)
+		Utility::BlockMedia("/boot", true);
+
 	if (fUserMode) {
 		BLaunchRoster roster;
 		BLaunchRoster::Private(roster).RegisterSessionDaemon(this);

src/servers/launch/Utility.cpp

@@ -0,0 +1,80 @@
+/*
+ * Copyright 2015, Axel Dörfler, axeld@pinc-software.de.
+ * Distributed under the terms of the MIT License.
+ */
+
+
+#include "Utility.h"
+
+#include <errno.h>
+#include <stdio.h>
+#include <string.h>
+
+#include <device/scsi.h>
+#include <DiskDevice.h>
+#include <DiskDeviceRoster.h>
+#include <fs_info.h>
+#include <Volume.h>
+
+
+namespace Utility {
+
+
+bool
+IsReadOnlyVolume(dev_t device)
+{
+	BVolume volume;
+	status_t status = volume.SetTo(device);
+	if (status != B_OK) {
+		fprintf(stderr, "Failed to get BVolume for device %" B_PRIdDEV
+			": %s\n", device, strerror(status));
+		return false;
+	}
+
+	BDiskDeviceRoster roster;
+	BDiskDevice diskDevice;
+	BPartition* partition;
+	status = roster.FindPartitionByVolume(volume, &diskDevice, &partition);
+	if (status != B_OK) {
+		fprintf(stderr, "Failed to get partition for device %" B_PRIdDEV
+			": %s\n", device, strerror(status));
+		return false;
+	}
+
+	return partition->IsReadOnly();
+}
+
+
+bool
+IsReadOnlyVolume(const char* path)
+{
+	return IsReadOnlyVolume(dev_for_path(path));
+}
+
+
+status_t
+BlockMedia(const char* path, bool block)
+{
+	fs_info info;
+	if (fs_stat_dev(dev_for_path(path), &info) == B_OK) {
+		if (strcmp(info.fsh_name, "devfs") != 0)
+			path = info.device_name;
+	}
+
+	int device = open(path, O_RDONLY);
+	if (device < 0)
+		return device;
+
+	status_t status = B_OK;
+
+	if (ioctl(device, B_SCSI_PREVENT_ALLOW, &block, sizeof(block)) != 0) {
+		fprintf(stderr, "Failed to block media on %s: %s\n", path,
+			strerror(errno));
+		status = errno;
+	}
+	close(device);
+	return status;
+}
+
+
+}	// namespace Utility

src/servers/launch/Utility.h

@@ -0,0 +1,20 @@
+/*
+ * Copyright 2015, Axel Dörfler, axeld@pinc-software.de.
+ * Distributed under the terms of the MIT License.
+ */
+#ifndef UTILITY_H
+#define UTILITY_H
+
+
+#include <SupportDefs.h>
+
+
+namespace Utility {
+	bool IsReadOnlyVolume(dev_t device);
+	bool IsReadOnlyVolume(const char* path);
+
+	status_t BlockMedia(const char* path, bool block);
+}
+
+
+#endif // UTILITY_H