I am writing a Go application for Mac and Windows, which will perform some action whenever there is a network change( Client move from Wi-fi 1 to Wi-fi 2 or to 3G to LAN). I am aware of a solution for Application running on mac in swift language but I am looking for a platform-agnostic solution here.
So far I have tried checking for an event on an interface but I am not sure if that is sufficient.
I expect that on a network change (moving from Wifi-1 to Wifi-2 or 3G or LAN) my Go app should be able to know to take some action.
I doubt there would be such a solution.
Every project which tries to provide some platform-agnostic solution to an inherently OS-tied problem inevitably hides the platform-specific details behind a common API.
Look at https://github.com/fsnotify/fsnotify for a good example.
So, I'd take that route and would have put up a package which would have two platform-specific "backends" which would be compiled conditionally using build tags.
To get notified about network-related events under Windows,
you should probably start here.
Unfortunately, this stuff is COM-oriented, but you could use https://github.com/go-ole/go-ole to help with that.
You might also ask a non-Go-specific question tagged winapi to ask about what would be the best way to hook into the kernel to get notified about the availability of the networks.
There is no platform agnostic solution that exists, however platforms like OSx,Linux,Windiws has ways to get network events with their platform specific limitations.
OSx: Raw socket SOCK_RAW of AF_ROUTE type can be used to detect any network events that occurs in user machine. there are various types of network event that can be detected.
This thread talk about an example on BSD for network event
Windows : Windows has its APIs given as part of iphlpapi library. APIs like NotifyAddrChange, NotifyRouteChange allows you to have almost all network events( apart from metric change etc.) this git repo has a working example NotifyAddrChange, which gives back and event whenever a interface goes down or comes up.
Linux : In Linux netlink sockets allows a user space application to receive network events using netlink sockets.
Related
If I use the IOKit methods to list USB devices, I can get something like "AirPod Case", but I don't know how to get "Francisco's AirPods". I've looked around a the various keys you can ask for, but none I've found bring up these "settable" names, only the standard "product names".
I don't know the answer as a fact, but I can give you some ideas for chasing it down:
The customised name is probably transferred as part of a higher-level protocol, or via vendor specific requests, not via standardised USB device descriptors. There is a small chance it might be advertised via a vendor specific descriptor, but this seems unlikely
I don't own any AirPods, so I don't know what kind of data protocol the AirPod case uses for communicating with a Mac, but you can try to find documentation or source code for that protocol, for example in case anyone has worked out how to use them from Linux and written a tool or library for that.
Finally, you can reverse engineer it yourself, by logging the USB traffic to and from the device when using existing software that is capable of reading the name you are after. On macOS, it's possible to do this using Wireshark. Start logging USB traffic, launch the software that talks to the device, then trawl through the logs to see if you can spot the string, then work out what request caused it to be returned.
I am trying to port Wine 1.7.13 to modern Cocoa. I am considering running Windows binaries in an XPC service’s process, for security isolation and crash-proofing. However, there is one problem: To the best of my knowledge, XPC services are singletons. Only one XPC service process is allowed to be running at a time. This is a problem because, if I use threads to enable multiple Windows binaries to run at once, a segfault or other hard crash in one Windows binary would cause all the other binaries to crash with it.
As mentioned here, it is generally understood that the above assertion is true. If that is so, it would seem that I cannot implement this sort of isolation within a single XPC service process.
My other alternative is to use sandbox inheritance (having the GUI application fork and using more traditional IPC to have the Windows processes talk to each other) instead of an XPC service. What are the pros and cons of using that instead of an XPC service? I understand that processes that inherit their parent’s sandbox does not get to have its own entitlements. What other drawbacks are there?
I also understand that Apple discourages the use of sandbox inheritance in favor of XPC, but it is still an available design decision. They must have kept it around for a reason. Would a sandboxed Mac App Store app be able to use sandbox inheritance in this fashion?
I am going through the same decision. I had my heart set on XPC services, but upon discovering that there would be a single XPC Service with multiple connections, I cannot use them (my XPC Service will use plug-ins provided by third-parties so I want to keep them apart, and also the XPC Service will use libraries that might not clean-up properly, so I want to be able to dispose of them while keeping the UI stable - well I shouldn't have to justify this - I want one-process-per-job and that's that).
I am considering the normal sub-process model using posix_spawn() (I think this behaves better than fork() WRT to Sandboxing), CocoaAsyncSocket for the comms. I am going to see if I can replace the use of TCP/IP in CocoaAsynSocket with UNIX sockets to speed-up up comms (with the intent of contributing it back to the project if this works out). (UPDATE: this has already been done, some time ago by github user #jdiehl. See his socketUN branch and the discussion in issue #88 of the upstream repo).
For data marshalling I will use Google Protocol Buffers (UPDATE #2: Nope; not worth the hassle when NSKeyedArchiver and NSKeyedUnarchiver provide everything required out-of-the box. They may not provide data as packed as Google Protocol Buffers, but they 1) Don't require writing and maintaining, 2) Allow any class to participate by implementing the NSCoding protocol, and 3) Don't have to solve the issue of cross-platform data exchange.
The only possible disadvantage I can see is I don't know if file bookmarks can be passed to the subprocess and used (i.e. the UI opens a file or has a file dragged to it and wants to give access to the file to the worker process). I will update this answer with whatever I learn. (FINAL UPDATE: Passing the URL bookmark across the UNIX domain socket works fine, and the bookmark doesn't even need to be a security-scoped bookmark for this to work. There are no more impediments to this alternative to XPC).
Your assertion is incorrect about sub-processes not having their own entitlements; they do and are embedded into the executable and it must have "inherits sandbox" set for the sub-process to work correctly.
And the end-of-the-day the one-xpc-service-per-app is a show stopper so you have no choice but to find an alternative.
! For the sake of simplifying things I will refer to Windows Store applications (also known as Metro or Modern UI) as "app" and to common desktop applications as "application" !
I believe this is still one of the most unclear yet important questions concerning app-development for developers who already have established applications on the market:
How to manage communication between apps and applications on a Windows 8 system? (please let's not start a debate on principles - there're so many use cases where this is really required!)
I basically read hundrets of articles in the last few days but still it remains unclear how to proceed doing it right from the first time. Mainly because I found several conflicting information.
With my question here I'd like to re-approach this problem from the viewpoint of the final Windows 8 possibilities.
Given situation:
App and application run on same system
1:1 communication
Application is native (written in Delphi)
Administrator or if required even system privileges are available for the application
In 90% of the use cases the app requests an action to be performed by the application and receives some textual result. The app shouldn't be left nor frozen for this!
In 10% the application performs an action (triggered by some event) and informs the app - the result might be: showing certain info on the tile or in the already running and active app or if possible running the app / bringing it to the foreground.
Now the "simple" question is, how to achieve this?
Is local webserver access actually allowed now? (I believe it wasn't for a long time but now is since the final release)
WCF? (-> apparently MS doesn't recommend that anymore)
HTTP requests on a local REST/SOAP server?
WinRT syndication API? (another form of webservice access with RSS/atom responses)
WebSockets (like MessageWebSocket)?
Some other form of TCP/IP communication?
Sharing a text file for in- and output (actually simply thinking of this hurts, but at least that's a possibility MS can't block...)
Named Pipes are not allowed, right?
There are some discussions on this topic here on SO, however most of them are not up-to-date anymore as MS changed a lot before releasing the final version of Windows 8. Instead of mixing up old and new information I'd like to find a definite and current answer to this problem for me and for all the other Windows application and app developers. Thank you!
If you are talking about an application going into the Store, communication with the local system via any mechanism is not allowed. Communication with the local system is supported in some debug scenarios to make app development easier.
You can launch desktop applications from Windows Store applications with file or protocol handlers, but there is no direct communication.
So, to reiterate the point... communication between WinRT and the desktop is not allowed for released Windows Store applications. Communication between the two environments is allowed in debug only.
The PG has posted in different places reasons for why communication is not allowed, ranging from security, to the WinRT lifecycle (i.e., you app gets suspended - how does that get handled re: resources, sockets, remote app, etc. -- lots of failure points) and the fact that Store apps cannot have a dependency on external programs (i.e., I need your local desktop app/service for the app to run, but how do I get your app/service installed? You cannot integrate into the Store app. You can provide another Store desktop app entry, but that is a bad user experience.) Those are high level summaries, of course.
I stumbled upon Private Eye and wonder how it works.
I.e. what APIs it is using to get those information (all incoming/outcoming network connections and the application using it)?
It is installing a kext. Is that needed?
Developer here.
It uses a kext to catch the connections. The basic idea is to install a socket filter that gets called whenever there is a network event. The kext will then grab and store whatever information it needs, and communicate it over a kernel control socket to the userland client.
Here's Apple's great intro about making a network kernel extension. http://developer.apple.com/library/mac/#documentation/Darwin/Conceptual/NKEConceptual/intro/intro.html
Almost everything in that applies to Private Eye.
chrome://net-internals/#events from google chrome may help, you can try
How could a (Windows) desktop application be created to monitor the amount of time spent on a particular website?
My first idea was to play with the Host file to intercept requests, log, and proxy. This feels a bit clunky; and I suspect my program would look like malware.
I feel like there is a smarter way? Any ideas?
There is a tool similar to what you are looking for called K-9 Web Protection. It is more used for parents to monitor what their kids are up to when hooked up to the internet. I have installed this for my niece's computer with good results and praises as it blocks, content filter, restrict internet times. This may be OTT for your needs but worth a shot as you can see what sites were visited.
The other, is to use a dedicated firewall monitoring solution such as IPCOP which is a Linux based distribution with a sole purpose in providing a proxy, stateful packet inspection (SPI) firewall, Intrusion Detection System (IDS).
Hope this helps,
Best regards,
Tom.
You could do this by monitoring active connections via netstat, or if you need more advanced data you can install The Windows Packet Capture Library and get any data about network use, and inside your desktop app, find network traffic that relates to 'spending time' on a website (which might just be GET requests for you, but I don't know), and record various statistics as required.
Route the traffic through a scriptable proxy and change the browser settings to point to that proxy.