[tahoe-dev] Authority to DoS via WAPI

[zooko]

Thanks, Toby!

I applied your patch, [3440], and I have the following comments or  
requests about it:

1.  Please add doc to http://allmydata.org/trac/tahoe/browser/docs/ 
configuration.txt about this option.  Possibly in http:// 
allmydata.org/trac/tahoe/browser/docs/frontends/webapi.txt as well.

2.  Do I understand correctly that this prevents people from doing  
any PUTs or POSTs to URLs that begin with "uri/"?  That seems just  
about right -- it prevents adding new files or changing the contents  
of files even if you know the write-cap to a file or a directory.   
But what about the check, verify, repair, manifest, and stats  
commands listed at the end of webapi.txt.  I'm not 100% sure why we  
made these available through POST instead of through GET -- perhaps  
because they have the "side effect" of causing a potentially large  
amount of CPU, network, and disk work even though they don't have any  
"side effects" on the filesystem graph of directories and files.   
Currently, if web.ambient_upload_authority is false then you can't do  
those check, repair, etc. operations.  Is that what you intend?

3.  Maybe for the test we could use du() from fileutil (http:// 
allmydata.org/trac/tahoe/browser/src/allmydata/util/fileutil.py ,  
also known as http://allmydata.org/trac/pyutil/browser/pyutil/pyutil/ 
fileutil.py ) to assert that the filesystem usage on the server isn't  
greater after the client attempted to upload something.

Regards,

Zooko

patches mentioned in this e-mail:

http://allmydata.org/trac/tahoe/changeset/3440