Re: [Zope-dev] uuid.UUID as a rock in zope.security

2009-04-11 Thread Chris Withers
Martijn Faassen wrote:
> 
> b) prevent someone from viewing something with a public view because 
> they don't have access to content-level methods and attributes. (which I 
> take is your "HTTP request as untrusted code" scenario). (alternate 
> strategies are Grok's, which has view-level security but allows 
> content-level declarations about what's accessible or not. But prominent 
> Grok users are clamoring for something closer to the traditional 
> approach with real content level protections)

Well, I like the idea of always having a back-stop on an object that 
says "I won't allow you to access bits of the current object that the 
user I currently think you're representing isn't allowed to access".

Stopping caring about rocks so much makes that no longer the case.

Chris

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Re: [Zope-dev] uuid.UUID as a rock in zope.security

2009-04-11 Thread Chris Withers
Martijn Faassen wrote:
> Isn't zope.security a protection system against *accidental* mistakes in 
> building secure applications? I.e. I call a method and then I find out I 
> have no such access. Do we really need to protect the developer against 
> more arcane workarounds?

Yes, that's its stated aim, and I want to rely on that, so I care a lot.

> If I *want* to work around the security system deliberately I can simply 
> remove the security proxy and be done with it. It's not like the system 
> is protecting against this anyway.

Well, not if you don't have access to that removal code.

Chris

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Re: [Zope-dev] uuid.UUID as a rock in zope.security

2009-04-10 Thread Jim Fulton

On Apr 10, 2009, at 3:20 PM, Shane Hathaway wrote:

> Martijn Faassen wrote:
>> Stephan Richter wrote:
>>> On Friday 10 April 2009, Jim Fulton wrote:
> Unfortunately these are ZC's use cases.
 They are not just ZC's use cases.
>>> Keas is relying on that safety heavily too. Anyone who wants to  
>>> build a secure
>>> DSL based on Python really wants zope.security.
>>
>> Okay, second case of such usage noticed.
>>
>> One thing that worries me is that PyPy folks keep saying it probably
>> isn't really secure, though they refuse to specify why not when Chris
>> Withers tried to find out last year at EuroPython.
>
> I suspect that's because Python allows anything by default;
> zope.security and RestrictedPython only provide a way to close known
> holes.

Wrong in the case of zope.security.  zope.security uses security  
proxies that only allow what is specifically allowed and deny  
everything else.  Because zope.proxy is written in C, there's no way  
to defeat it in Python.
The other potential holes I'm aware of are with:

- rocks, which I'm very conservative with, and

- __builtins__.  You have to construct builtins very carefully, which  
we do and make sure you avoid certain problematic builtins, which we  
also do.

It's hard to guess what they might be referring to, since they don't  
provide any specifics.

Jim

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Re: [Zope-dev] uuid.UUID as a rock in zope.security

2009-04-10 Thread Shane Hathaway
Martijn Faassen wrote:
> Stephan Richter wrote:
>> On Friday 10 April 2009, Jim Fulton wrote:
 Unfortunately these are ZC's use cases.
>>> They are not just ZC's use cases.
>> Keas is relying on that safety heavily too. Anyone who wants to build a 
>> secure 
>> DSL based on Python really wants zope.security.
> 
> Okay, second case of such usage noticed.
> 
> One thing that worries me is that PyPy folks keep saying it probably 
> isn't really secure, though they refuse to specify why not when Chris 
> Withers tried to find out last year at EuroPython.

I suspect that's because Python allows anything by default; 
zope.security and RestrictedPython only provide a way to close known 
holes.  The security model of Javascript running in a browser is very 
similar, though, and that seems to be good enough for most people.

Shane
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Re: [Zope-dev] uuid.UUID as a rock in zope.security

2009-04-10 Thread Martijn Faassen
Hey,

Jim Fulton wrote:
[snip]
> I don't see the point of a separate package. This is a very small  
> corner of zope.security.

Sure, it could be solved within zope.security as well.

> A simple API for extending the definition of rocks would be enough to  
> deal with this particular issue.
> 
> Note that "considered immutable" is rather vague.  UUIDs aren't  
> immutable if you're willing to be only slightly devious.  But if you  
> aren't worried about that in an application, then that isn't a  
> problem.  You might even choose to make truly mutable objects into  
> rocks if you know your application is going to play nice.

Right, I meant "considered immutable" in the dynamically typed sense. I 
can make classes that I consider to be immutable after creation in 
Python, even though I don't actually enforce it by preventing people 
from setting attributes on them.

>> People trying to port zope.security dependent code to the google app
>> engine seem to have yet another use case. This is fulfilled right  
>> now by
>> a hacked up fork that at least makes import works, even though none of
>> the actual functionality is there. We might want to put a knob in
>> zope.security to support this hack out of the box too.
> 
> Or tell them to use something else altogether.  It all depends on  
> their use cases.  If they want a seatbelt rather than a space suit, I  
> suppose a python-based proxy could be good enough, although it would  
> likely be too slow for that environment.

The use case appears to be to use code that depends on zope.security on 
the google app engine. We have quite few libraries that do that out 
there. I think they just simply hack the proxy creation out completely, 
meaning that zope.security is basically a no-op. I asked what exactly is 
going on in another thread, so we just wait until we find out. :)

Regards,

Martijn

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Re: [Zope-dev] uuid.UUID as a rock in zope.security

2009-04-10 Thread Zvezdan Petkovic
On Apr 10, 2009, at 12:31 PM, Hanno Schlichting wrote:
> We are in the business of content management. The most valuable
> information the system and the entire physical machine has is the
> content in the system. You don't run web applications on any kind of
> shared servers where the system has any more valuable data.
>
> A person who is allowed to steal or delete the entire content is  
> what I call trusted. The potential additional damage of that person  
> breaking out of the web application is a minor concern compared to  
> this. Allowing any kind of TTW development is always going to be an  
> explicit opt-in, but if you are willing to allow this, we won't try  
> to stop you with limited access anymore.


So, it's quite black and white.

I would argue that there are several classes of users.  At least these:

1. Trusted users inside your organization that makes the software.The  
role they get through their credentials has highest trust level and  
they could be allowed to do the most TTW.

2. Trusted users inside your customer organization.  Those are usually  
the techies in the customer organization who configure your software  
to run the way they want.  The role they get through their credentials  
has some trust level.  They can change certain things TTW.

3. Untrusted users in your customer organization.  These users get a  
role through their credentials that allows them to configure the  
software parts, but cannot do any TTW changes.

4. Untrusted customers of your customer organization.  Plain web  
users.  They just view the content.

The granularity levels can be even finer between 1, 2, and 3 above.
This allows for various shades of grey.

However, since anybody's credentials can be stolen,  I do not want to  
allow rock changes and arbitrary imports even to the users in class 1  
above.  Because:

1. they have the highest trust level in that web app, but
2. they are just an ordinary user on a machine running that web app, and
3. there are people who have higher credentials on that machine --  
sysadmins.

That's why leaving zope.security safer by default is the right thing.
If you want to allow more, wrap around it someorg.lesssecurity
or even someorg.nosecurity.

Zvezdan

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Re: [Zope-dev] uuid.UUID as a rock in zope.security

2009-04-10 Thread Jim Fulton

On Apr 10, 2009, at 12:26 PM, Martijn Faassen wrote:
...
>>> b) prevent someone from viewing something with a public view because
>>> they don't have access to content-level methods and attributes.
>>> (which I
>>> take is your "HTTP request as untrusted code" scenario).
>>
>> It is an example of that scenario, yes.
>
> Do you have other examples?

The view doesn't have to be public.  For example, the view might only  
be accessible to people with a particular role, and you might further  
limit what they can do based on the data they can access.

...

>> It's worth noting that applications that don't allow untrusted code
>> (other than the request) but that still want to use the protection
>> system to protect content can can be much more liberal about what is
>> treated as a rock by declaring rock classes themselves. The  
>> mechanisms
>> support this now, although there may not be an API.
>
> This is what I was aiming at. Would it be possible to have a
> zope.sandbox that builds on zope.security that does the whole  
> untrusted
> execution thing, and then we have another profile of zope.security  
> that
> just allows everything considered immutable as rocks? Can such things
> exist in parallel in the same code base?

I don't see the point of a separate package. This is a very small  
corner of zope.security.
A simple API for extending the definition of rocks would be enough to  
deal with this particular issue.

Note that "considered immutable" is rather vague.  UUIDs aren't  
immutable if you're willing to be only slightly devious.  But if you  
aren't worried about that in an application, then that isn't a  
problem.  You might even choose to make truly mutable objects into  
rocks if you know your application is going to play nice.

...

> People trying to port zope.security dependent code to the google app
> engine seem to have yet another use case. This is fulfilled right  
> now by
> a hacked up fork that at least makes import works, even though none of
> the actual functionality is there. We might want to put a knob in
> zope.security to support this hack out of the box too.


Or tell them to use something else altogether.  It all depends on  
their use cases.  If they want a seatbelt rather than a space suit, I  
suppose a python-based proxy could be good enough, although it would  
likely be too slow for that environment.

Jim

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Zope Corporation


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Re: [Zope-dev] uuid.UUID as a rock in zope.security

2009-04-10 Thread Hanno Schlichting
Zvezdan Petkovic wrote:
> On Apr 10, 2009, at 11:32 AM, Hanno Schlichting wrote:
>> We do have the use-case of allowing trusted people to add templates or
>> code TTW and many other things like data level and view based  
>> security.
>> The RestrictedPython case however is something we will gladly give up.
> 
> Trusted people!?
> Are you checking their ID at the door?
> 
> All you have in terms of trust are their credentials.

Sure, that's called authentication. Happens to be the same in any
technical or physical world.

> You don't want to allow many, many things TTW, even if they logged in  
> with the trusted credentials.

We are in the business of content management. The most valuable
information the system and the entire physical machine has is the
content in the system. You don't run web applications on any kind of
shared servers where the system has any more valuable data.

A person who is allowed to steal or delete the entire content is what I
call trusted. The potential additional damage of that person breaking
out of the web application is a minor concern compared to this. Allowing
any kind of TTW development is always going to be an explicit opt-in,
but if you are willing to allow this, we won't try to stop you with
limited access anymore.

Hanno

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Re: [Zope-dev] uuid.UUID as a rock in zope.security

2009-04-10 Thread Martijn Faassen
Hey,

Jim Fulton wrote:
> On Apr 10, 2009, at 10:43 AM, Martijn Faassen wrote:
>> and Zope 2 isn't
>> using zope.security anyway.
> 
> That's immaterial.  I was talking about the use case.

It's hard to tell whether Zope 2 will ever adopt zope.security to 
fulfill this use case - I have the impression the big apps are trying to 
move away from Zope 2, and Plone at least seems to be moving away from 
untrusted code.

I think that's interesting in figuring out where we can and cannot go 
with zope.security.

[snip]
>> I take it that zope.security is supporting three use cases:
>>
>> a) prevent an application developer for making mistakes concerning
>> security,
> 
> Yes
> 
>> or alternatively, forcing developers to think about security
>> in-depth.
> 
> That is obviously not a goal. No one is forcing anyone to do anything.  
> You don't have to use zope.security.

Some systems come with zope.security out of the box, such as traditional 
Zope 3, meaning normal development with it forces developers to think 
about this. I'm not saying this is a bad thing; it is a different 
perspective on "preventing an application developer from making mistakes".

>> b) prevent someone from viewing something with a public view because
>> they don't have access to content-level methods and attributes.  
>> (which I
>> take is your "HTTP request as untrusted code" scenario).
> 
> It is an example of that scenario, yes.

Do you have other examples?

[snip]
>> c) allow Python/template untrusted code
> 
> Yes.  This is where proper handling of "rocks" is most important.
> 
>> As far as I now know, the only actual applications of zope.security to
>> accomplish c) are ZC's.
> 
> I'm sure there are others. 

Yes, as Stephan said, Keas.

> Zope 2's protection scheme addresses this  
> use case as well, although not as well.

>> a) and b) would be served well enough if zope.security only cared  
>> about
>> preventing accidental security violations.
> 
> I'm not sure what you mean by "accidental" here, but I suspect I  
> disagree. I would agree that handling of rocks is far less important  
> in this context.

Okay, let's just agree on the latter. :)

[snip]
>> Would there be a way to isolate these use cases so that other users in
>> the community did not have to worry about this anymore? I ask because
>> the topic has come up a few times already (now, and with the
>> Python-based i18n message ids a while back).
[snip]
> It's worth noting that applications that don't allow untrusted code  
> (other than the request) but that still want to use the protection  
> system to protect content can can be much more liberal about what is  
> treated as a rock by declaring rock classes themselves. The mechanisms  
> support this now, although there may not be an API.

This is what I was aiming at. Would it be possible to have a 
zope.sandbox that builds on zope.security that does the whole untrusted 
execution thing, and then we have another profile of zope.security that 
just allows everything considered immutable as rocks? Can such things 
exist in parallel in the same code base?

I'm not saying that if so, we're going to do the work immediately. I 
just want to explore what directions we could go in if someone does want 
to do the work.

People trying to port zope.security dependent code to the google app 
engine seem to have yet another use case. This is fulfilled right now by 
a hacked up fork that at least makes import works, even though none of 
the actual functionality is there. We might want to put a knob in 
zope.security to support this hack out of the box too.

Regards,

Martijn

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Re: [Zope-dev] uuid.UUID as a rock in zope.security

2009-04-10 Thread Martijn Faassen
Stephan Richter wrote:
> On Friday 10 April 2009, Jim Fulton wrote:
>>> Unfortunately these are ZC's use cases.
>> They are not just ZC's use cases.
> 
> Keas is relying on that safety heavily too. Anyone who wants to build a 
> secure 
> DSL based on Python really wants zope.security.

Okay, second case of such usage noticed.

One thing that worries me is that PyPy folks keep saying it probably 
isn't really secure, though they refuse to specify why not when Chris 
Withers tried to find out last year at EuroPython.

Regards,

Martijn


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Re: [Zope-dev] uuid.UUID as a rock in zope.security

2009-04-10 Thread Zvezdan Petkovic
On Apr 10, 2009, at 11:32 AM, Hanno Schlichting wrote:
> We do have the use-case of allowing trusted people to add templates or
> code TTW and many other things like data level and view based  
> security.
> The RestrictedPython case however is something we will gladly give up.

Trusted people!?
Are you checking their ID at the door?

All you have in terms of trust are their credentials.
You don't want to allow many, many things TTW, even if they logged in  
with the trusted credentials.

Otherwise, you give them the same credentials on your physical machine  
that serves that app (e.g. they import os TTW).

Finally, even if you are fine with allowing that because you trust  
them, who guarantees that every login with those credentials is really  
that trusted person?

Zvezdan

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Re: [Zope-dev] uuid.UUID as a rock in zope.security

2009-04-10 Thread Hanno Schlichting
Jim Fulton wrote:
> On Apr 10, 2009, at 10:43 AM, Martijn Faassen wrote:
> 
>> I know that Plone is moving away from untrusted code,
> 
> I predict they won't, but we'll see.

Well, it's on the roadmap to move away from it. The use case of allowing
untrusted users to add Python code TTW to the system simply doesn't
exist anymore.

We do have the use-case of allowing trusted people to add templates or
code TTW and many other things like data level and view based security.
The RestrictedPython case however is something we will gladly give up.

Hanno

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Re: [Zope-dev] uuid.UUID as a rock in zope.security

2009-04-10 Thread Stephan Richter
On Friday 10 April 2009, Jim Fulton wrote:
> > Unfortunately these are ZC's use cases.
>
> They are not just ZC's use cases.

Keas is relying on that safety heavily too. Anyone who wants to build a secure 
DSL based on Python really wants zope.security.

Regards,
Stephan
-- 
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Google me. "Zope Stephan Richter"
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Re: [Zope-dev] uuid.UUID as a rock in zope.security

2009-04-10 Thread Jim Fulton

On Apr 10, 2009, at 10:43 AM, Martijn Faassen wrote:
...
> I know that Plone is moving away from untrusted code,

I predict they won't, but we'll see.

> and Zope 2 isn't
> using zope.security anyway.

That's immaterial.  I was talking about the use case.

> That leaves ZC's applications, which I
> imagine are based on zope.security?

Yes, not that it is really relevant to the discussion.

>> (Note that, in some ways, HTTP requests represent untrusted code.
>> This case can often be handled by simple resource-protection schemes,
>> although some applications can still benefit from the Zope 3
>> protection scheme, which can help mediate access to content when  
>> fine-
>> grained control is needed.)
>
> I take it that zope.security is supporting three use cases:
>
> a) prevent an application developer for making mistakes concerning
> security,

Yes

> or alternatively, forcing developers to think about security
> in-depth.

That is obviously not a goal. No one is forcing anyone to do anything.  
You don't have to use zope.security.

> b) prevent someone from viewing something with a public view because
> they don't have access to content-level methods and attributes.  
> (which I
> take is your "HTTP request as untrusted code" scenario).

It is an example of that scenario, yes.

> (alternate
> strategies are Grok's, which has view-level security but allows
> content-level declarations about what's accessible or not. But  
> prominent
> Grok users are clamoring for something closer to the traditional
> approach with real content level protections)

Interesting. Note that Zope 3's protection system addresses this case  
while Zope 2's system doesn't. This is one of the reasons I'd like to  
see Zope 2 move to the Zope 3 protection system.

> c) allow Python/template untrusted code

Yes.  This is where proper handling of "rocks" is most important.

> As far as I now know, the only actual applications of zope.security to
> accomplish c) are ZC's.

I'm sure there are others.  Zope 2's protection scheme addresses this  
use case as well, although not as well.

> a) and b) would be served well enough if zope.security only cared  
> about
> preventing accidental security violations.

I'm not sure what you mean by "accidental" here, but I suspect I  
disagree. I would agree that handling of rocks is far less important  
in this context.

> If this is correct, this is interesting; we are taking on a burden  
> for a
> rather limited set of use cases.

What burden?  The protection system benefits all the use cases.  It's  
also a burden that is easily removed if you don't have these use cases.

> Unfortunately these are ZC's use cases.

They are not just ZC's use cases.

> Would there be a way to isolate these use cases so that other users in
> the community did not have to worry about this anymore? I ask because
> the topic has come up a few times already (now, and with the
> Python-based i18n message ids a while back).

Sure. If you (think you) don't need a protection system, or think you  
can design a lighter weight one that meets your needs, then don't use  
zope.security.

By far, most of the pain of Zope 3 protection system, as well as it's  
power, comes from the use of security proxies. The handling of rocks  
is a minor issue.

It's worth noting that applications that don't allow untrusted code  
(other than the request) but that still want to use the protection  
system to protect content can can be much more liberal about what is  
treated as a rock by declaring rock classes themselves. The mechanisms  
support this now, although there may not be an API.

Jim

--
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Zope Corporation


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Re: [Zope-dev] uuid.UUID as a rock in zope.security

2009-04-10 Thread Martijn Faassen
Jim Fulton wrote:
> On Apr 10, 2009, at 9:25 AM, Martijn Faassen wrote:
[snip]
>> Protecting against workarounds is useful if you allow through the web
>> manipulation of code itself. But who is actually doing this?

> The purpose of the protection system is to protect an application  
> against untrusted code provided by people other than the application  
> develoer.  If an application has no untrusted code, then the  
> protection system isn't necessary. I'll guess that 99% of applications  
> don't support untrusted code and don't need the Zope protection  
> system(s).  The applications people build with Grok probably fall in  
> this category, or one would hope. :)

> There are some applications, such as Zope 2, Plone, and many of our  
> (ZC's) applications that support untrusted code and, for these  
> systems, the protection system is critical.  It doesn't protect the  
> application developer from herself, it protects her from the people  
> writing the untrusted code.

I know that Plone is moving away from untrusted code, and Zope 2 isn't 
using zope.security anyway. That leaves ZC's applications, which I 
imagine are based on zope.security?

 > (Note that, in some ways, HTTP requests represent untrusted code.
 > This case can often be handled by simple resource-protection schemes,
 > although some applications can still benefit from the Zope 3
 > protection scheme, which can help mediate access to content when fine-
 > grained control is needed.)

I take it that zope.security is supporting three use cases:

a) prevent an application developer for making mistakes concerning 
security, or alternatively, forcing developers to think about security 
in-depth.

b) prevent someone from viewing something with a public view because 
they don't have access to content-level methods and attributes. (which I 
take is your "HTTP request as untrusted code" scenario). (alternate 
strategies are Grok's, which has view-level security but allows 
content-level declarations about what's accessible or not. But prominent 
Grok users are clamoring for something closer to the traditional 
approach with real content level protections)

c) allow Python/template untrusted code

As far as I now know, the only actual applications of zope.security to 
accomplish c) are ZC's.

a) and b) would be served well enough if zope.security only cared about 
preventing accidental security violations.

If this is correct, this is interesting; we are taking on a burden for a 
rather limited set of use cases. Unfortunately these are ZC's use cases. 
Would there be a way to isolate these use cases so that other users in 
the community did not have to worry about this anymore? I ask because 
the topic has come up a few times already (now, and with the 
Python-based i18n message ids a while back).

It could be that c) grows more important again over time in case of a 
"rebirth of the ZMI", but that doesn't look like it's about to happen 
any time soon. And if it does it might happen in a more limited way that 
doesn't require a sophisticated untrusted code infrastructure.

Regards,

Martijn

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Re: [Zope-dev] uuid.UUID as a rock in zope.security

2009-04-10 Thread Jim Fulton

On Apr 10, 2009, at 9:25 AM, Martijn Faassen wrote:

> Hi there,
>
> One fundamental question about this that I have is why we want to
> protect the user against such loopholes anyway?
>
> Isn't zope.security a protection system against *accidental*  
> mistakes in
> building secure applications?

No

> I.e. I call a method and then I find out I
> have no such access. Do we really need to protect the developer  
> against
> more arcane workarounds?
>
> If I *want* to work around the security system deliberately I can  
> simply
> remove the security proxy and be done with it. It's not like the  
> system
> is protecting against this anyway.
>
> Protecting against workarounds is useful if you allow through the web
> manipulation of code itself. But who is actually doing this?


The purpose of the protection system is to protect an application  
against untrusted code provided by people other than the application  
develoer.  If an application has no untrusted code, then the  
protection system isn't necessary. I'll guess that 99% of applications  
don't support untrusted code and don't need the Zope protection  
system(s).  The applications people build with Grok probably fall in  
this category, or one would hope. :)

There are some applications, such as Zope 2, Plone, and many of our  
(ZC's) applications that support untrusted code and, for these  
systems, the protection system is critical.  It doesn't protect the  
application developer from herself, it protects her from the people  
writing the untrusted code.

(Note that, in some ways, HTTP requests represent untrusted code.   
This case can often be handled by simple resource-protection schemes,  
although some applications can still benefit from the Zope 3  
protection scheme, which can help mediate access to content when fine- 
grained control is needed.)

Jim

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Zope Corporation


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Re: [Zope-dev] uuid.UUID as a rock in zope.security

2009-04-10 Thread Martijn Faassen
Hi there,

One fundamental question about this that I have is why we want to 
protect the user against such loopholes anyway?

Isn't zope.security a protection system against *accidental* mistakes in 
building secure applications? I.e. I call a method and then I find out I 
have no such access. Do we really need to protect the developer against 
more arcane workarounds?

If I *want* to work around the security system deliberately I can simply 
remove the security proxy and be done with it. It's not like the system 
is protecting against this anyway.

Protecting against workarounds is useful if you allow through the web 
manipulation of code itself. But who is actually doing this?

Regards,

Martijn

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Re: [Zope-dev] uuid.UUID as a rock in zope.security

2009-04-10 Thread Jim Fulton

On Apr 3, 2009, at 2:57 AM, Brian Sutherland wrote:

> Hi,
>
> We're using UUIDs a lot, and it's pretty painful that they are  
> security
> proxied. They're in the standard library from python 2.5
> (http://docs.python.org/library/uuid.html) and are immutable according
> to the documentation.

"According to the documentation" isn't good enough.

> I think they meet all the all the requirements to be rocks. So unless
> someone complains, I'll commit the attached patch in a few days.


 >>> u = uuid.UUID('{12345678-1234-5678-1234-567812345678}')
 >>> u.__dict__['int'] = 1
 >>> u
UUID('----0001')

This isn't exactly immutable.  The protection system would prevent  
this sort of mutation, but I'm still nervous about a rock implemented  
in Python.  We have to be darn sure that there isn't some sort of loop  
hole here.  Really we have to do this with any rock and I'm not sure  
we have the formalisms necessary to guide this.

Oh wait:

 >>> del u.int
 >>> u
Traceback (most recent call last):
   File "", line 1, in 
   File "/usr/local/python/2.5.1/lib/python2.5/uuid.py", line 192, in  
__repr__
 return 'UUID(%r)' % str(self)
   File "/usr/local/python/2.5.1/lib/python2.5/uuid.py", line 198, in  
__str__
 hex = '%032x' % self.int
AttributeError: 'UUID' object has no attribute 'int'

Oops. This would not be prevented by the protection system. -1 for  
making uuids rocks.

Jim

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Zope Corporation


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[Zope-dev] uuid.UUID as a rock in zope.security

2009-04-02 Thread Brian Sutherland
Hi,

We're using UUIDs a lot, and it's pretty painful that they are security
proxied. They're in the standard library from python 2.5
(http://docs.python.org/library/uuid.html) and are immutable according
to the documentation.

I think they meet all the all the requirements to be rocks. So unless
someone complains, I'll commit the attached patch in a few days.

-- 
Brian Sutherland
Index: CHANGES.txt
===
--- CHANGES.txt (revision 98805)
+++ CHANGES.txt (working copy)
@@ -5,7 +5,8 @@
 3.6.4 (unreleased)
 --
 
-- None so far.
+- Make uuid.UUID a rock, they are immutable and in the python standad library
+  from python 2.5.
 
 3.6.3 (2009-03-23)
 --
Index: src/zope/security/checker.py
===
--- src/zope/security/checker.py(revision 98805)
+++ src/zope/security/checker.py(working copy)
@@ -624,6 +624,13 @@
 type(pytz.UTC): NoProxy,
 })
 
+try:
+# NOTE: remove try/except when we depend on python2.5 and up. uuid in 
standard library from python 2.5.
+from uuid import UUID
+BasicTypes[UUID] = NoProxy
+except ImportError:
+pass
+
 # Available for tests. Located here so it can be kept in sync with BasicTypes.
 BasicTypes_examples = {
 object: object(),
Index: src/zope/security/tests/test_standard_checkers.py
===
--- src/zope/security/tests/test_standard_checkers.py   (revision 98805)
+++ src/zope/security/tests/test_standard_checkers.py   (working copy)
@@ -424,6 +424,14 @@
 >>> from pytz import UTC
 >>> int(type(ProxyFactory(  UTC )) is type(UTC))
 1
+
+>>> try:
+... # NOTE: remove try/except when we depend on python 2.5 and greater 
(uuid in standard library)
+... from uuid import UUID
+... int(type(ProxyFactory(  UUID('12345678123456781234567812345678') 
)) is UUID)
+... except ImportError:
+... 1
+1
 """
 
 def test_iter_of_sequences():
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