Xamarin.Android and user downloadable executable code (.dll)












2














I have a question regarding this bullet point of the Malicious Behavior policy.





  • Apps or SDKs that download executable code, such as dex files or native code, from a source other than Google Play.


    Does an app fall into that category if the user can use it to download and run .NET assemblies (IL) from the NuGet gallery? More specifically: Xamarin.Android bindings.


    .NET assemblies by themselves should fall into the "JavaScript" category or "code that runs in a virtual machine and has limited access to Android APIs".


    However Android bindings contain native executable code which can technically be considered potentially malicious. A simple example would be downloading a native binding like "Refractored.GifImageView". Which is just a convenient library.



    The app itself is an educational tool for C#. It compiles and runs user C# code on their device.










share|improve this question





























    2














    I have a question regarding this bullet point of the Malicious Behavior policy.





    • Apps or SDKs that download executable code, such as dex files or native code, from a source other than Google Play.


      Does an app fall into that category if the user can use it to download and run .NET assemblies (IL) from the NuGet gallery? More specifically: Xamarin.Android bindings.


      .NET assemblies by themselves should fall into the "JavaScript" category or "code that runs in a virtual machine and has limited access to Android APIs".


      However Android bindings contain native executable code which can technically be considered potentially malicious. A simple example would be downloading a native binding like "Refractored.GifImageView". Which is just a convenient library.



      The app itself is an educational tool for C#. It compiles and runs user C# code on their device.










    share|improve this question



























      2












      2








      2







      I have a question regarding this bullet point of the Malicious Behavior policy.





      • Apps or SDKs that download executable code, such as dex files or native code, from a source other than Google Play.


        Does an app fall into that category if the user can use it to download and run .NET assemblies (IL) from the NuGet gallery? More specifically: Xamarin.Android bindings.


        .NET assemblies by themselves should fall into the "JavaScript" category or "code that runs in a virtual machine and has limited access to Android APIs".


        However Android bindings contain native executable code which can technically be considered potentially malicious. A simple example would be downloading a native binding like "Refractored.GifImageView". Which is just a convenient library.



        The app itself is an educational tool for C#. It compiles and runs user C# code on their device.










      share|improve this question















      I have a question regarding this bullet point of the Malicious Behavior policy.





      • Apps or SDKs that download executable code, such as dex files or native code, from a source other than Google Play.


        Does an app fall into that category if the user can use it to download and run .NET assemblies (IL) from the NuGet gallery? More specifically: Xamarin.Android bindings.


        .NET assemblies by themselves should fall into the "JavaScript" category or "code that runs in a virtual machine and has limited access to Android APIs".


        However Android bindings contain native executable code which can technically be considered potentially malicious. A simple example would be downloading a native binding like "Refractored.GifImageView". Which is just a convenient library.



        The app itself is an educational tool for C#. It compiles and runs user C# code on their device.







      c# android xamarin.android google-play






      share|improve this question















      share|improve this question













      share|improve this question




      share|improve this question








      edited Nov 12 at 21:47

























      asked Nov 11 at 22:08









      radostin dimitrov

      1111




      1111
























          2 Answers
          2






          active

          oldest

          votes


















          0














          Well this a first time well basically the malicious behavior policy says that




          Apps or SDKs that download executable code, such as dex files or native code, from a source other than Google Play




          But what you seem to be missing is that this policy applies when your application is downloading an exe i.e. an executable file.(Emphasis on the application)



          Now when you talk about nuget packages your application is not downloading the nuget packages it is basically being downloaded by vs then when you make an apk it gets converted into a Java Android Executable i.e. the APK now this apk is not downloading anything in app its already downloaded and bundled in so "the malicious behavior" policy doesn't apply at all in your scenario.



          I hope it helps, Revert in case of queries






          share|improve this answer





















          • To clarify I'm not asking if an application can be compiled and published with nuget packages. Obviously that's a yes. In this scenario additional packages can be downloaded at runtime. So yes this is an in app download initiated by the user.
            – radostin dimitrov
            Nov 12 at 10:51










          • So basically your application is downloading NuGet packages afterwards?
            – G.hakim
            Nov 13 at 5:23










          • Yes, exactly. Afterwards the user can make the application download NuGet packages
            – radostin dimitrov
            Nov 13 at 9:18










          • Well I am not sure if this makes your application fall under the category or not most probably I would say it does, so I would suggest you get in touch with Google Play Support and ask them whether or not your application falls under that category or not and if yes what can be a suitable resolution as I do not think anyone has probably done what you are trying to do here.
            – G.hakim
            Nov 13 at 10:21










          • Google support can be quite hard to reach but I guess it's the only viable option left. Thanks anyway
            – radostin dimitrov
            Nov 13 at 11:03



















          0














          I don't speak for Google Play policy but I think it is extremely unlikely this would be allowed. Google Play has this policy to protect Android users from malicious code. Making app developers put all their code in the APK has two advantages:




          • it allows Google's abuse teams to look for malware before the app is published, so protect users

          • it prevents developers from having accidental security holes, where an attacked could attack the network or the server, and create arbitrary code for a user to execute on the device, even if the original developer did not intend anything malicious. App developers have made lots of mistakes in this area in the past.


          Downloading arbitrary packages from NuGet at runtime sounds like it would be extremely dangerous from both counts, and so I suspect Google Play Policy won't allow it.



          Have you considered the new Google Play feature dynamic delivery to accomplish what you want?






          share|improve this answer





















          • I don't know if dynamic delivery is supported for Xamarin.Android.
            – radostin dimitrov
            Nov 16 at 19:45










          • It isn't an option as I could only add the "most popular" packages. Even then it would be hundreds of packages with complex dependencies (several hundred more maybe). They would have to be compressed to reduce the number of additional apks so a user will still end up with too much taken up space. Or worse: 1 huge apk with everything. Also with such an app or even a scripting/task app a user could theoretically always use it to download something malicious, so by that logic the entire basic concept of many apps is in violation. The ansewers I got from google support were basically "don't know"
            – radostin dimitrov
            Nov 16 at 20:04










          • Forgot to mention. "Making app developers put all their code in the APK". I, the developer am not using the Nuget packages . Only the user within their own code
            – radostin dimitrov
            Nov 16 at 20:29











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          2 Answers
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          2 Answers
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          0














          Well this a first time well basically the malicious behavior policy says that




          Apps or SDKs that download executable code, such as dex files or native code, from a source other than Google Play




          But what you seem to be missing is that this policy applies when your application is downloading an exe i.e. an executable file.(Emphasis on the application)



          Now when you talk about nuget packages your application is not downloading the nuget packages it is basically being downloaded by vs then when you make an apk it gets converted into a Java Android Executable i.e. the APK now this apk is not downloading anything in app its already downloaded and bundled in so "the malicious behavior" policy doesn't apply at all in your scenario.



          I hope it helps, Revert in case of queries






          share|improve this answer





















          • To clarify I'm not asking if an application can be compiled and published with nuget packages. Obviously that's a yes. In this scenario additional packages can be downloaded at runtime. So yes this is an in app download initiated by the user.
            – radostin dimitrov
            Nov 12 at 10:51










          • So basically your application is downloading NuGet packages afterwards?
            – G.hakim
            Nov 13 at 5:23










          • Yes, exactly. Afterwards the user can make the application download NuGet packages
            – radostin dimitrov
            Nov 13 at 9:18










          • Well I am not sure if this makes your application fall under the category or not most probably I would say it does, so I would suggest you get in touch with Google Play Support and ask them whether or not your application falls under that category or not and if yes what can be a suitable resolution as I do not think anyone has probably done what you are trying to do here.
            – G.hakim
            Nov 13 at 10:21










          • Google support can be quite hard to reach but I guess it's the only viable option left. Thanks anyway
            – radostin dimitrov
            Nov 13 at 11:03
















          0














          Well this a first time well basically the malicious behavior policy says that




          Apps or SDKs that download executable code, such as dex files or native code, from a source other than Google Play




          But what you seem to be missing is that this policy applies when your application is downloading an exe i.e. an executable file.(Emphasis on the application)



          Now when you talk about nuget packages your application is not downloading the nuget packages it is basically being downloaded by vs then when you make an apk it gets converted into a Java Android Executable i.e. the APK now this apk is not downloading anything in app its already downloaded and bundled in so "the malicious behavior" policy doesn't apply at all in your scenario.



          I hope it helps, Revert in case of queries






          share|improve this answer





















          • To clarify I'm not asking if an application can be compiled and published with nuget packages. Obviously that's a yes. In this scenario additional packages can be downloaded at runtime. So yes this is an in app download initiated by the user.
            – radostin dimitrov
            Nov 12 at 10:51










          • So basically your application is downloading NuGet packages afterwards?
            – G.hakim
            Nov 13 at 5:23










          • Yes, exactly. Afterwards the user can make the application download NuGet packages
            – radostin dimitrov
            Nov 13 at 9:18










          • Well I am not sure if this makes your application fall under the category or not most probably I would say it does, so I would suggest you get in touch with Google Play Support and ask them whether or not your application falls under that category or not and if yes what can be a suitable resolution as I do not think anyone has probably done what you are trying to do here.
            – G.hakim
            Nov 13 at 10:21










          • Google support can be quite hard to reach but I guess it's the only viable option left. Thanks anyway
            – radostin dimitrov
            Nov 13 at 11:03














          0












          0








          0






          Well this a first time well basically the malicious behavior policy says that




          Apps or SDKs that download executable code, such as dex files or native code, from a source other than Google Play




          But what you seem to be missing is that this policy applies when your application is downloading an exe i.e. an executable file.(Emphasis on the application)



          Now when you talk about nuget packages your application is not downloading the nuget packages it is basically being downloaded by vs then when you make an apk it gets converted into a Java Android Executable i.e. the APK now this apk is not downloading anything in app its already downloaded and bundled in so "the malicious behavior" policy doesn't apply at all in your scenario.



          I hope it helps, Revert in case of queries






          share|improve this answer












          Well this a first time well basically the malicious behavior policy says that




          Apps or SDKs that download executable code, such as dex files or native code, from a source other than Google Play




          But what you seem to be missing is that this policy applies when your application is downloading an exe i.e. an executable file.(Emphasis on the application)



          Now when you talk about nuget packages your application is not downloading the nuget packages it is basically being downloaded by vs then when you make an apk it gets converted into a Java Android Executable i.e. the APK now this apk is not downloading anything in app its already downloaded and bundled in so "the malicious behavior" policy doesn't apply at all in your scenario.



          I hope it helps, Revert in case of queries







          share|improve this answer












          share|improve this answer



          share|improve this answer










          answered Nov 11 at 23:32









          G.hakim

          2,8191627




          2,8191627












          • To clarify I'm not asking if an application can be compiled and published with nuget packages. Obviously that's a yes. In this scenario additional packages can be downloaded at runtime. So yes this is an in app download initiated by the user.
            – radostin dimitrov
            Nov 12 at 10:51










          • So basically your application is downloading NuGet packages afterwards?
            – G.hakim
            Nov 13 at 5:23










          • Yes, exactly. Afterwards the user can make the application download NuGet packages
            – radostin dimitrov
            Nov 13 at 9:18










          • Well I am not sure if this makes your application fall under the category or not most probably I would say it does, so I would suggest you get in touch with Google Play Support and ask them whether or not your application falls under that category or not and if yes what can be a suitable resolution as I do not think anyone has probably done what you are trying to do here.
            – G.hakim
            Nov 13 at 10:21










          • Google support can be quite hard to reach but I guess it's the only viable option left. Thanks anyway
            – radostin dimitrov
            Nov 13 at 11:03


















          • To clarify I'm not asking if an application can be compiled and published with nuget packages. Obviously that's a yes. In this scenario additional packages can be downloaded at runtime. So yes this is an in app download initiated by the user.
            – radostin dimitrov
            Nov 12 at 10:51










          • So basically your application is downloading NuGet packages afterwards?
            – G.hakim
            Nov 13 at 5:23










          • Yes, exactly. Afterwards the user can make the application download NuGet packages
            – radostin dimitrov
            Nov 13 at 9:18










          • Well I am not sure if this makes your application fall under the category or not most probably I would say it does, so I would suggest you get in touch with Google Play Support and ask them whether or not your application falls under that category or not and if yes what can be a suitable resolution as I do not think anyone has probably done what you are trying to do here.
            – G.hakim
            Nov 13 at 10:21










          • Google support can be quite hard to reach but I guess it's the only viable option left. Thanks anyway
            – radostin dimitrov
            Nov 13 at 11:03
















          To clarify I'm not asking if an application can be compiled and published with nuget packages. Obviously that's a yes. In this scenario additional packages can be downloaded at runtime. So yes this is an in app download initiated by the user.
          – radostin dimitrov
          Nov 12 at 10:51




          To clarify I'm not asking if an application can be compiled and published with nuget packages. Obviously that's a yes. In this scenario additional packages can be downloaded at runtime. So yes this is an in app download initiated by the user.
          – radostin dimitrov
          Nov 12 at 10:51












          So basically your application is downloading NuGet packages afterwards?
          – G.hakim
          Nov 13 at 5:23




          So basically your application is downloading NuGet packages afterwards?
          – G.hakim
          Nov 13 at 5:23












          Yes, exactly. Afterwards the user can make the application download NuGet packages
          – radostin dimitrov
          Nov 13 at 9:18




          Yes, exactly. Afterwards the user can make the application download NuGet packages
          – radostin dimitrov
          Nov 13 at 9:18












          Well I am not sure if this makes your application fall under the category or not most probably I would say it does, so I would suggest you get in touch with Google Play Support and ask them whether or not your application falls under that category or not and if yes what can be a suitable resolution as I do not think anyone has probably done what you are trying to do here.
          – G.hakim
          Nov 13 at 10:21




          Well I am not sure if this makes your application fall under the category or not most probably I would say it does, so I would suggest you get in touch with Google Play Support and ask them whether or not your application falls under that category or not and if yes what can be a suitable resolution as I do not think anyone has probably done what you are trying to do here.
          – G.hakim
          Nov 13 at 10:21












          Google support can be quite hard to reach but I guess it's the only viable option left. Thanks anyway
          – radostin dimitrov
          Nov 13 at 11:03




          Google support can be quite hard to reach but I guess it's the only viable option left. Thanks anyway
          – radostin dimitrov
          Nov 13 at 11:03













          0














          I don't speak for Google Play policy but I think it is extremely unlikely this would be allowed. Google Play has this policy to protect Android users from malicious code. Making app developers put all their code in the APK has two advantages:




          • it allows Google's abuse teams to look for malware before the app is published, so protect users

          • it prevents developers from having accidental security holes, where an attacked could attack the network or the server, and create arbitrary code for a user to execute on the device, even if the original developer did not intend anything malicious. App developers have made lots of mistakes in this area in the past.


          Downloading arbitrary packages from NuGet at runtime sounds like it would be extremely dangerous from both counts, and so I suspect Google Play Policy won't allow it.



          Have you considered the new Google Play feature dynamic delivery to accomplish what you want?






          share|improve this answer





















          • I don't know if dynamic delivery is supported for Xamarin.Android.
            – radostin dimitrov
            Nov 16 at 19:45










          • It isn't an option as I could only add the "most popular" packages. Even then it would be hundreds of packages with complex dependencies (several hundred more maybe). They would have to be compressed to reduce the number of additional apks so a user will still end up with too much taken up space. Or worse: 1 huge apk with everything. Also with such an app or even a scripting/task app a user could theoretically always use it to download something malicious, so by that logic the entire basic concept of many apps is in violation. The ansewers I got from google support were basically "don't know"
            – radostin dimitrov
            Nov 16 at 20:04










          • Forgot to mention. "Making app developers put all their code in the APK". I, the developer am not using the Nuget packages . Only the user within their own code
            – radostin dimitrov
            Nov 16 at 20:29
















          0














          I don't speak for Google Play policy but I think it is extremely unlikely this would be allowed. Google Play has this policy to protect Android users from malicious code. Making app developers put all their code in the APK has two advantages:




          • it allows Google's abuse teams to look for malware before the app is published, so protect users

          • it prevents developers from having accidental security holes, where an attacked could attack the network or the server, and create arbitrary code for a user to execute on the device, even if the original developer did not intend anything malicious. App developers have made lots of mistakes in this area in the past.


          Downloading arbitrary packages from NuGet at runtime sounds like it would be extremely dangerous from both counts, and so I suspect Google Play Policy won't allow it.



          Have you considered the new Google Play feature dynamic delivery to accomplish what you want?






          share|improve this answer





















          • I don't know if dynamic delivery is supported for Xamarin.Android.
            – radostin dimitrov
            Nov 16 at 19:45










          • It isn't an option as I could only add the "most popular" packages. Even then it would be hundreds of packages with complex dependencies (several hundred more maybe). They would have to be compressed to reduce the number of additional apks so a user will still end up with too much taken up space. Or worse: 1 huge apk with everything. Also with such an app or even a scripting/task app a user could theoretically always use it to download something malicious, so by that logic the entire basic concept of many apps is in violation. The ansewers I got from google support were basically "don't know"
            – radostin dimitrov
            Nov 16 at 20:04










          • Forgot to mention. "Making app developers put all their code in the APK". I, the developer am not using the Nuget packages . Only the user within their own code
            – radostin dimitrov
            Nov 16 at 20:29














          0












          0








          0






          I don't speak for Google Play policy but I think it is extremely unlikely this would be allowed. Google Play has this policy to protect Android users from malicious code. Making app developers put all their code in the APK has two advantages:




          • it allows Google's abuse teams to look for malware before the app is published, so protect users

          • it prevents developers from having accidental security holes, where an attacked could attack the network or the server, and create arbitrary code for a user to execute on the device, even if the original developer did not intend anything malicious. App developers have made lots of mistakes in this area in the past.


          Downloading arbitrary packages from NuGet at runtime sounds like it would be extremely dangerous from both counts, and so I suspect Google Play Policy won't allow it.



          Have you considered the new Google Play feature dynamic delivery to accomplish what you want?






          share|improve this answer












          I don't speak for Google Play policy but I think it is extremely unlikely this would be allowed. Google Play has this policy to protect Android users from malicious code. Making app developers put all their code in the APK has two advantages:




          • it allows Google's abuse teams to look for malware before the app is published, so protect users

          • it prevents developers from having accidental security holes, where an attacked could attack the network or the server, and create arbitrary code for a user to execute on the device, even if the original developer did not intend anything malicious. App developers have made lots of mistakes in this area in the past.


          Downloading arbitrary packages from NuGet at runtime sounds like it would be extremely dangerous from both counts, and so I suspect Google Play Policy won't allow it.



          Have you considered the new Google Play feature dynamic delivery to accomplish what you want?







          share|improve this answer












          share|improve this answer



          share|improve this answer










          answered Nov 16 at 8:42









          Nick Fortescue

          5,4111422




          5,4111422












          • I don't know if dynamic delivery is supported for Xamarin.Android.
            – radostin dimitrov
            Nov 16 at 19:45










          • It isn't an option as I could only add the "most popular" packages. Even then it would be hundreds of packages with complex dependencies (several hundred more maybe). They would have to be compressed to reduce the number of additional apks so a user will still end up with too much taken up space. Or worse: 1 huge apk with everything. Also with such an app or even a scripting/task app a user could theoretically always use it to download something malicious, so by that logic the entire basic concept of many apps is in violation. The ansewers I got from google support were basically "don't know"
            – radostin dimitrov
            Nov 16 at 20:04










          • Forgot to mention. "Making app developers put all their code in the APK". I, the developer am not using the Nuget packages . Only the user within their own code
            – radostin dimitrov
            Nov 16 at 20:29


















          • I don't know if dynamic delivery is supported for Xamarin.Android.
            – radostin dimitrov
            Nov 16 at 19:45










          • It isn't an option as I could only add the "most popular" packages. Even then it would be hundreds of packages with complex dependencies (several hundred more maybe). They would have to be compressed to reduce the number of additional apks so a user will still end up with too much taken up space. Or worse: 1 huge apk with everything. Also with such an app or even a scripting/task app a user could theoretically always use it to download something malicious, so by that logic the entire basic concept of many apps is in violation. The ansewers I got from google support were basically "don't know"
            – radostin dimitrov
            Nov 16 at 20:04










          • Forgot to mention. "Making app developers put all their code in the APK". I, the developer am not using the Nuget packages . Only the user within their own code
            – radostin dimitrov
            Nov 16 at 20:29
















          I don't know if dynamic delivery is supported for Xamarin.Android.
          – radostin dimitrov
          Nov 16 at 19:45




          I don't know if dynamic delivery is supported for Xamarin.Android.
          – radostin dimitrov
          Nov 16 at 19:45












          It isn't an option as I could only add the "most popular" packages. Even then it would be hundreds of packages with complex dependencies (several hundred more maybe). They would have to be compressed to reduce the number of additional apks so a user will still end up with too much taken up space. Or worse: 1 huge apk with everything. Also with such an app or even a scripting/task app a user could theoretically always use it to download something malicious, so by that logic the entire basic concept of many apps is in violation. The ansewers I got from google support were basically "don't know"
          – radostin dimitrov
          Nov 16 at 20:04




          It isn't an option as I could only add the "most popular" packages. Even then it would be hundreds of packages with complex dependencies (several hundred more maybe). They would have to be compressed to reduce the number of additional apks so a user will still end up with too much taken up space. Or worse: 1 huge apk with everything. Also with such an app or even a scripting/task app a user could theoretically always use it to download something malicious, so by that logic the entire basic concept of many apps is in violation. The ansewers I got from google support were basically "don't know"
          – radostin dimitrov
          Nov 16 at 20:04












          Forgot to mention. "Making app developers put all their code in the APK". I, the developer am not using the Nuget packages . Only the user within their own code
          – radostin dimitrov
          Nov 16 at 20:29




          Forgot to mention. "Making app developers put all their code in the APK". I, the developer am not using the Nuget packages . Only the user within their own code
          – radostin dimitrov
          Nov 16 at 20:29


















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