Add ability to run --install on command-line tool with a blockfile and end date (instead of using settings)

Author: cstigler

AppController.m

@@ -890,22 +890,15 @@ - (IBAction)save:(id)sender {
 
 	/* if successful, save file under designated name */
 	if (runResult == NSOKButton) {
-		[defaults_ synchronize];
-		NSString* err;
-		NSDictionary* saveDict = @{@"HostBlacklist": [settings_ valueForKey: @"Blocklist"],
-								   @"BlockAsWhitelist": [settings_ valueForKey: @"BlockAsWhitelist"]};
-		NSData* saveData = [NSPropertyListSerialization dataFromPropertyList: saveDict format: NSPropertyListBinaryFormat_v1_0 errorDescription: &err];
-		if(err) {
-			NSError* displayErr = [NSError errorWithDomain: kSelfControlErrorDomain code: -902 userInfo: @{NSLocalizedDescriptionKey: [@"Error 902: " stringByAppendingString: err]}];
+        NSString* errDescription;
+        [SCUtilities writeBlocklistToFileURL: sp.URL settings: settings_ errorDescription: &errDescription];
+
+        if(errDescription) {
+			NSError* displayErr = [NSError errorWithDomain: kSelfControlErrorDomain code: -902 userInfo: @{NSLocalizedDescriptionKey: [@"Error 902: " stringByAppendingString: errDescription]}];
+            NSBeep();
 			[NSApp presentError: displayErr];
 			return;
 		}
-		if (![saveData writeToURL: sp.URL atomically: YES]) {
-			NSBeep();
-		} else {
-			NSDictionary* attribs = @{NSFileExtensionHidden: @YES};
-			[[NSFileManager defaultManager] setAttributes: attribs ofItemAtPath: [sp.URL path] error: NULL];
-		}
 	}
 }
 
@@ -917,10 +910,10 @@ - (IBAction)open:(id)sender {
 	long result = [oPanel runModal];
 	if (result == NSOKButton) {
 		if([oPanel.URLs count] > 0) {
-			NSDictionary* openedDict = [NSDictionary dictionaryWithContentsOfURL: oPanel.URLs[0]];
-			[settings_ setValue: openedDict[@"HostBlacklist"] forKey: @"Blocklist"];
-            [settings_ setValue: openedDict[@"BlockAsWhitelist"] forKey: @"BlockAsWhitelist"];
-			BOOL domainListIsOpen = [[domainListWindowController_ window] isVisible];
+            [SCUtilities readBlocklistFromFile: oPanel.URLs[0] toSettings: settings_];
+
+            // close the domain list (and reopen again if need be to refresh)
+            BOOL domainListIsOpen = [[domainListWindowController_ window] isVisible];
 			NSRect frame = [[domainListWindowController_ window] frame];
 			[self closeDomainList];
 			if(domainListIsOpen) {

ERRORS

@@ -23,6 +23,9 @@
 -217 - Could not write lock file.
 -218 - Could not remove lock file.
 -219 - Trying to add block but lock file already found.  Please try again.
+-220 - Block end date argument is invalid
+-221 - Block could not be read from file
+-221 - Block is already running (so we can't start another)
 
 -901 - Selected sound not found.
 -902 - Error serializing blocklist for save

HelperCommon.h

@@ -29,6 +29,11 @@
 #import <sysexits.h>
 #import "HostFileBlocker.h"
 #import "SelfControlCommon.h"
+#import "SCUtilities.h"
+#import "SCSettings.h"
+
+// Uses seteuid to check both settings and defaults for whether the block is running, or not
+BOOL blockIsRunningInSettingsOrDefaults(uid_t controllingUID);
 
 // Reads the domain block list from the settings for SelfControl, and adds deny
 // rules for all of the IPs (or the A DNS record IPS for doamin names) to the

HelperCommon.m

@@ -13,6 +13,25 @@
 #import "SCSettings.h"
 #import "SCConstants.h"
 
+BOOL blockIsRunningInSettingsOrDefaults(uid_t controllingUID) {
+    SCSettings* settings = [SCSettings settingsForUser: controllingUID];
+
+    // pull up the user's defaults to check for the existence of a legacy block
+    // to do that, we have to seteuid to the controlling UID so NSUserDefaults thinks we're them
+    seteuid(controllingUID);
+    NSUserDefaults* defaults = [NSUserDefaults standardUserDefaults];
+    [defaults addSuiteNamed: @"org.eyebeam.SelfControl"];
+    [defaults synchronize];
+    
+    BOOL response = [SCUtilities blockIsRunningWithSettings: settings defaults: defaults];
+    
+    // reset the euid so nothing else gets funky
+    [NSUserDefaults resetStandardUserDefaults];
+    seteuid(0);
+    
+    return response;
+}
+
 void addRulesToFirewall(uid_t controllingUID) {
     SCSettings* settings = [SCSettings settingsForUser: controllingUID];
     BOOL shouldEvaluateCommonSubdomains = [[settings valueForKey: @"EvaluateCommonSubdomains"] boolValue];

HelperMain.m

@@ -58,18 +58,52 @@ int main(int argc, char* argv[]) {
         SCSettings* settings = [SCSettings settingsForUser: controllingUID];
 
 		if([modeString isEqual: @"--install"]) {
+            if (blockIsRunningInSettingsOrDefaults(controllingUID)) {
+                NSLog(@"ERROR: Block is already running");
+                printStatus(-222);
+                exit(EX_CONFIG);
+            }
+
 			NSFileManager* fileManager = [NSFileManager defaultManager];
 
 			// Initialize writeErr to nil so calling messages on it later don't cause
 			// crashes (it doesn't make sense we need to do this, but whatever).
 			NSError* writeErr = nil;
 			NSString* plistFormatPath = [[NSBundle mainBundle] pathForResource:@"org.eyebeam.SelfControl"
 																		ofType:@"plist"];
-
 			NSString* plistFormatString = [NSString stringWithContentsOfFile: plistFormatPath  encoding: NSUTF8StringEncoding error: NULL];
+            
+            // while the main app will just expect us to fetch the blocklist / end date from settings
+            // this helper tool can also be used via command line with no other settings
+            // (ex: by auto-selfcontrol) and in that case they'll pass a blocklist file and the end date via args
+            // we should read those values into settings for use later
+            NSString* pathToBlocklistFile;
+            NSDate* blockEndDateArg;
+            if (argv[3] != NULL && argv[4] != NULL) {
+                pathToBlocklistFile = @(argv[3]);
+                blockEndDateArg = [[NSISO8601DateFormatter new] dateFromString: @(argv[4])];
+                                
+                // if we didn't get a valid block end date in the future, ignore the other args
+                if (blockEndDateArg == nil || [blockEndDateArg timeIntervalSinceNow] < 1) {
+                    pathToBlocklistFile = nil;
+                    NSLog(@"Error: Block end date argument %@ is invalid", @(argv[4]));
+                    printStatus(-220);
+                    exit(EX_IOERR);
+                } else {
+                    [settings setValue: blockEndDateArg forKey: @"BlockEndDate"];
+                    BOOL readSuccess = [SCUtilities readBlocklistFromFile: [NSURL fileURLWithPath: pathToBlocklistFile] toSettings: settings];
+                    
+                    if (!readSuccess) {
+                        NSLog(@"ERROR: Block could not be read from file %@", pathToBlocklistFile);
+                        printStatus(-221);
+                        exit(EX_IOERR);
+                    }
+                }
+            }
 
 			// get the expiration minute, to make sure we run the helper then (if it hasn't run already)
-            NSDate* blockEndDate = [settings valueForKey: @"BlockEndDate"];
+            // use the block end date from the argument if it's available; otherwise fall back to the one in settings
+            NSDate* blockEndDate = (blockEndDateArg != nil) ? blockEndDateArg : [settings valueForKey: @"BlockEndDate"];
 			NSCalendar* calendar = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
 			NSDateComponents* components = [calendar components: NSMinuteCalendarUnit fromDate: blockEndDate];
 			long expirationMinute = [components minute];

SCUtilities.h

@@ -41,4 +41,8 @@
 + (BOOL) blockIsRunningInLegacyDictionary:(NSDictionary*)dict;
 + (NSDate*) endDateFromLegacyBlockDictionary:(NSDictionary *)dict;
 
+// read and write saved block files
++ (BOOL)writeBlocklistToFileURL:(NSURL*)targetFileURL settings:(SCSettings*)settings errorDescription:(NSString**)errDescriptionRef;
++ (BOOL)readBlocklistFromFile:(NSURL*)fileURL toSettings:(SCSettings*)settings;
+
 @end

SCUtilities.m

@@ -200,4 +200,41 @@ + (NSDate*) endDateFromLegacyBlockDictionary:(NSDictionary *)dict {
     return [startDate dateByAddingTimeInterval: (duration * 60)];
 }
 
++ (BOOL)writeBlocklistToFileURL:(NSURL*)targetFileURL settings:(SCSettings*)settings errorDescription:(NSString**)errDescriptionRef {
+    NSDictionary* saveDict = @{@"HostBlacklist": [settings valueForKey: @"Blocklist"],
+                               @"BlockAsWhitelist": [settings valueForKey: @"BlockAsWhitelist"]};
+
+    NSString* saveDataErr;
+    NSData* saveData = [NSPropertyListSerialization dataFromPropertyList: saveDict format: NSPropertyListBinaryFormat_v1_0 errorDescription: &saveDataErr];
+    if (saveDataErr != nil) {
+        *errDescriptionRef = saveDataErr;
+        return NO;
+    }
+
+    if (![saveData writeToURL: targetFileURL atomically: YES]) {
+        NSLog(@"ERROR: Failed to write blocklist to URL %@", targetFileURL);
+        return NO;
+    }
+    
+    // for prettiness sake, attempt to hide the file extension
+    NSDictionary* attribs = @{NSFileExtensionHidden: @YES};
+    [[NSFileManager defaultManager] setAttributes: attribs ofItemAtPath: [targetFileURL path] error: NULL];
+    
+    return YES;
+}
+
++ (BOOL)readBlocklistFromFile:(NSURL*)fileURL toSettings:(SCSettings*)settings {
+    NSDictionary* openedDict = [NSDictionary dictionaryWithContentsOfURL: fileURL];
+    
+    if (openedDict == nil || openedDict[@"HostBlacklist"] == nil || openedDict[@"BlockAsWhitelist"] == nil) {
+        NSLog(@"ERROR: Could not read a valid block from file %@", fileURL);
+        return NO;
+    }
+    
+    [settings setValue: openedDict[@"HostBlacklist"] forKey: @"Blocklist"];
+    [settings setValue: openedDict[@"BlockAsWhitelist"] forKey: @"BlockAsWhitelist"];
+    
+    return YES;
+}
+
 @end