Digest exception when using a protected zip file (with password) in the application package

[serge-xav]

If I add a password protected zip file in the application package, I get the following error with version 1.8.6 :

Exception in thread "main" java.io.IOException: Error computing digest for: externalProperties.zip
	at com.threerings.getdown.data.f.run(Unknown Source)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at java.lang.Thread.run(Thread.java:748)
Caused by: java.util.zip.ZipException: invalid CEN header (encrypted entry)
	at java.util.zip.ZipFile.open(Native Method)
	at java.util.zip.ZipFile.<init>(ZipFile.java:225)
	at java.util.zip.ZipFile.<init>(ZipFile.java:155)
	at java.util.zip.ZipFile.<init>(ZipFile.java:169)
	at com.threerings.getdown.data.Resource.computeDigest(Unknown Source)

The error is not present in version 1.7.X
I think the cause is the pull request #206 (comment)

I'm wondering if usage of zip files as resource, should be configurable, using a switch in getdown.txt file ? This would also close #275

[bekoenig]

Hi @serge-xav,

in my opinion computing zip file digest in a robust way is an important improvement. So #275 is the implication of a change to an unsafe implementation.

For your mentioned bug here, the best solution would be a fallback to the default digest calculcation, when the zip file is encrypted.

Another solution would be to change the extension to ".zip.dat", so getdown don't tries to open the file.

[serge-xav]

Hi @bekoenig, thanks for your comment.
I will try to implement your workaround for encrypted zip files. If a correction is needed on Getdown side, do you know when/how the new digest calculation has been implemented for zip files ? I tried to take a look at it, but I don't know how to implement the "fallback to default digest calculation when zip file is encrypted"

[bekoenig]

In the next weeks getdown 2.0.0 will be released with different group-id (see bekoenig/getdown#1). This version is feature complete and waits for final release. After this, I can implement this fallback in

getdown/core/src/main/java/com/threerings/getdown/data/Resource.java

Line 62 in 917b7c3

if (isZip){

and check for openable.

[serge-xav]

Hi again Benjamin, I did not see this announcment before, that's good news to see Getdown up and living. Do you want me to also create the issue on your project ?

[bekoenig]

You are welcome to open a new issue in my repository. I will try to fix it in the next month.

After the first release I will open a new issue here to mark this repository as deprecated and link to my fork. I'm new to github and opensource contribution, so I need time to adapt my wellknown processes.