41
votes

I want to enable access for assistive devices programatically on 10.9. On 10.8 and lower I was using following Applescript to enable access for assistive devices:

tell application "System Events"
if UI elements enabled is false then
    set UI elements enabled to true
end if
end tell

With 10.9, Apple has moved the accessibility options to System Preferences ➞ Security & Privacy ➞ Privacy ➞ Accessibility. Unlike previous versions of OS X, which used a universal checkbox for all applications, the new functionality in 10.9 allows users to individually choose which apps can gain control of the system to perform their various scripted functions.

The new system preferences regarding accessibility

Apple has NOT provided any API to developers to programmatically enable accessibility for an app. So Mac OS 10.9 will prompt a dialog for end user permission to enable Accessibility when application uses accessibility APIs. Additionally User has to Relaunch the application after enabling Accessibility.

Default prompt dialog put up by 10.9 OS for Xcode

Can we enable access for assistive devices programmatically on 10.9 using Applescript or any other APIs? Any help to fix this issue would be greatly appreciated.

9
No, there is no way to circumvent the need for visiting this screen. It is one of the operating system's base protections. Any way that is found to circumvent this will almost certainly be patched out.ChrisCM
I believe this is very intentional behavior that can't be circumvented. When you have access to accessibility you can copy text from text boxes, randomly click things, and just in general do some pretty sketchy stuff. While that stuff is super useful in some applications they don't want it to happen without the user knowing. But this is obviously a side affect of their Sandboxing efforts to make things more 'secure'Keith Smiley
You can "accept" it or not, but this is the way it is. I agree with the original commenter, if you did find a way to circumvent this, it would be eliminated ASAP.ipmcc
@KeithSmiley: AXIsTrustedProcess() will indeed start reporting YES as soon as the checkbox for the app is checked in Security & Privacy Preferences: but in my testing, new event taps will still silently fail to tap keyup/keydown events until the process is restarted. (Which is consistent with how AXMakeProcessTrusted() used to work.)Alun Bestor
@rjobidon I (finally!) figured out that you can drag an app from you Applications folder into the list. Triggering the "...would like to control this computer" dialog is covered in zoul's answer to this question.pkamb

9 Answers

45
votes

This doesn’t answer your question, but it’s good to know about a new API call that appeared in 10.9 and lets you display the authorization screen or bypass it:

NSDictionary *options = @{(id)kAXTrustedCheckOptionPrompt: @YES};
BOOL accessibilityEnabled = AXIsProcessTrustedWithOptions((CFDictionaryRef)options);

Passing YES will force the authorization screen to appear, passing NO will silently skip it. The return value is the same as the one returned by AXAPIEnabled(), which is getting deprecated in 10.9. To make sure that the function is available on your system, just compare it to NULL:

if (AXIsProcessTrustedWithOptions != NULL) {
    // 10.9 and later
} else {
    // 10.8 and older
}

You'll need to add ApplicationServices.framework to your project, and import to your .m or .h file:

#import <ApplicationServices/ApplicationServices.h>

It’s quite a pity that the authorization screen doesn’t let the user to authorize the app directly, it just opens the right part of the System Preferences. Which, by the way, you can do directly without going through the useless system dialogue:

tell application "System Preferences"
    set securityPane to pane id "com.apple.preference.security"
    tell securityPane to reveal anchor "Privacy_Accessibility"
    activate
end tell

or using Objective C:

NSString *urlString = @"x-apple.systempreferences:com.apple.preference.security?Privacy_Accessibility";
[[NSWorkspace sharedWorkspace] openURL:[NSURL URLWithString:urlString]];

This can be paired with the first code snippet to test whether accessibilityEnabled by passing @NO to kAXTrustedCheckOptionPrompt while preventing the system pop-up to appear and instead opening the Accessibility preferences pane directly:

NSDictionary *options = @{(id)kAXTrustedCheckOptionPrompt: @NO};
BOOL accessibilityEnabled = AXIsProcessTrustedWithOptions((CFDictionaryRef)options);
if (!accessibilityEnabled) {
    NSString *urlString = @"x-apple.systempreferences:com.apple.preference.security?Privacy_Accessibility";
    [[NSWorkspace sharedWorkspace] openURL:[NSURL URLWithString:urlString]];
}
11
votes

I'd recommend against using all the sqlite3 and AppleScript hacks as they might stop working in the future, there's also just a proper api for this.

To add on to this, you can actually monitor if the user clicks the accessibility setting for your app so you can do some actions when the user grants the permission.

(Swift 5, tested on Mojave, Catalina, Big Sur)

reading privileges:

private func readPrivileges(prompt: Bool) -> Bool {
    let options: NSDictionary = [kAXTrustedCheckOptionPrompt.takeRetainedValue() as NSString: prompt]
    let status = AXIsProcessTrustedWithOptions(options)
    return status
}

Monitoring for changes in accessibility:

DistributedNotificationCenter.default().addObserver(forName: NSNotification.Name("com.apple.accessibility.api"), object: nil, queue: nil) { _ in
  DispatchQueue.main.asyncAfter(deadline: .now() + 0.1) {
    self.updatePrivileges()
  }
}

It is best to read the privileges again after getting the notification as the notification itself doesn't really work in my experience. So inside the updatePrivileges(), run readPrivileges() to get the new status.

You need the delay because it takes some time for the changes to be reflected.

Another thing you need to keep in mind while monitoring is that a notification will be fired for any app that gets different permissions, so if the user grants or revokes a different app you'll still get a notification.

Also, don't forget to remove the observer when you don't need it anymore.

edit:

Source: Accessbility Testbench by Piddlesoft

10
votes

While @user2865860's answer works well, I though I'd post the entire code sample that works perfectly on 10.9 to save others some time. You need to get root privileges, so it will prompt a user to enter the password.

char *command= "/usr/bin/sqlite3";
char *args[] = {"/Library/Application Support/com.apple.TCC/TCC.db", "INSERT or REPLACE INTO access  VALUES('kTCCServiceAccessibility','com.yourapp',0,1,0,NULL);", nil};
AuthorizationRef authRef;
OSStatus status = AuthorizationCreate(NULL, kAuthorizationEmptyEnvironment, kAuthorizationFlagDefaults, &authRef);
if (status == errAuthorizationSuccess) {
    status = AuthorizationExecuteWithPrivileges(authRef, command, kAuthorizationFlagDefaults, args, NULL);
    AuthorizationFree(authRef, kAuthorizationFlagDestroyRights);
    if(status != 0){
        //handle errors...
    }
}
9
votes

You can edit the TCC.db file in directly. I had to do this in order to make Divvy install without user interaction. Just replace com.mizage.divvy with your program.

sudo sqlite3 /Library/Application\ Support/com.apple.TCC/TCC.db "INSERT INTO access VALUES('kTCCServiceAccessibility','com.mizage.divvy',0,1,1,NULL);" 

To remove the entry:

sudo sqlite3 /Library/Application\ Support/com.apple.TCC/TCC.db "delete from access where client='com.mizage.divvy';"
9
votes

I have found the following code snippet which properly requests Accessibility permissions in OS X 10.9:

if (AXIsProcessTrustedWithOptions != NULL) {
    // 10.9 and later
    const void * keys[] = { kAXTrustedCheckOptionPrompt };
    const void * values[] = { kCFBooleanTrue };

    CFDictionaryRef options = CFDictionaryCreate(
            kCFAllocatorDefault,
            keys,
            values,
            sizeof(keys) / sizeof(*keys),
            &kCFCopyStringDictionaryKeyCallBacks,
            &kCFTypeDictionaryValueCallBacks);

    return AXIsProcessTrustedWithOptions(options);
}

// OS X 10.8 and older
3
votes

I was struggling with this myself and after a bit of a research I found the following:

  1. Hacking the sqlite DB has the major drawback in using authorization services. First this will pop-up a dialog telling user that an application wants to install a utility helper (even though it is just one off launchd submission using SMJobSubmit). Second, it does not work for sandboxed apps and thus no app store.

  2. @Max Al Faeakh uses AuthorizationExecuteWithPrivileges which is deprecated. You need to use launchd with the above SMJobSubmit. Anyway, this still requires authorization. It also requires an auxiliary application like this one.

I guess the best is to use either:

NSDictionary *options = @{(id)kAXTrustedCheckOptionPrompt: @YES};
BOOL accessibilityEnabled = AXIsProcessTrustedWithOptions((CFDictionaryRef)options);

or

NSDictionary *options = @{(id)kAXTrustedCheckOptionPrompt: @NO};
BOOL accessibilityEnabled = AXIsProcessTrustedWithOptions((CFDictionaryRef)options);

and open preference pane manually using for example scripting bridge framework:

SBSystemPreferencesApplication *prefs = [SBApplication applicationWithBundleIdentifier:@"com.apple.systempreferences"];
[prefs activate];

SBSystemPreferencesPane *pane = [[prefs panes] find:^BOOL(SBSystemPreferencesPane *elem) {
  return [[elem id] isEqualToString:@"com.apple.preference.security"];
}];
SBSystemPreferencesAnchor *anchor = [[pane anchors] find:^BOOL(SBSystemPreferencesAnchor *elem) {
  return [[elem name] isEqualToString:@"Privacy_Accessibility"];
}];

[anchor reveal];

The SBSystemPreferencesPane class comes form a SBSystemPreferences.h file which can be generated:

sdef "/Applications/System Preferences.app" | sdp -fh --basename SBSystemPreferences -o SBSystemPreferences.h
2
votes

Thanks for this shell script samples from @NightFlight, which are really helpful. I used this with AppleScript in a Python application, like the following:

set sh to "touch /private/var/db/.AccessibilityAPIEnabled && sqlite3 \\"/Library/Application Support/com.apple.TCC/TCC.db\\" \\"INSERT or REPLACE INTO access VALUES('kTCCServiceAccessibility','com.godevnode',0,1,0,NULL);\\""
do shell script sh with administrator privileges

It worked well for me in Python code as a string.

Edit (Nov 7, 2014):

If you want to try this in AppleScript Editor, use a slightly different character escape as below:

set sh to "touch /private/var/db/.AccessibilityAPIEnabled && sqlite3 \"/Library/Application Support/com.apple.TCC/TCC.db\" \"INSERT or REPLACE INTO access VALUES('kTCCServiceAccessibility','com.godevnode',0,1,0,NULL);\""
do shell script sh with administrator privileges

For Mac OS X before 10.9, it's even simpler:

accessibility_api_file = "/private/var/db/.AccessibilityAPIEnabled"

def __enable_accessibility_api():
    try:
        script = 'do shell script "touch %s" with administrator ' \
                 'privileges' % accessibility_api_file
        result = applescript.AppleScript(script).run()
        log.debug("Tried to enable accessibility api, result=" + result)
        return True
    except applescript.ScriptError as err:
        log.error(str(err))
    return False

Just need to touch one file. The AppleScript mentioned in the Python code above can also be used in other languages.

1
votes

Thanks everyone.

I issue the following triggered from the login window to ensure control is given only to the items we want every session:

# Enable Service Accessibility for Textpander and others  
# Clear the acess table.
sqlite3 /Library/Application\ Support/com.apple.TCC/TCC.db "DELETE FROM access"

# Enter the access we wish to have.
sqlite3 /Library/Application\ Support/com.apple.TCC/TCC.db "INSERT INTO access VALUES ('kTCCServiceAccessibility','com.apple.systempreferences',0,1,1,NULL)"
sqlite3 /Library/Application\ Support/com.apple.TCC/TCC.db "INSERT INTO access VALUES ('kTCCServiceAccessibility','de.petermaurer.textpanderdaemon',0,1,1,NULL)"
0
votes

The sqlite3 "hack" is great.

I had to use permissions "1,1,1" (whatever that means) to make this work.

Note that the permission combination, not the client (ie. program name) is the unique database key.