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Posted to dev@syncope.apache.org by Isuranga Perera <is...@gmail.com> on 2018/04/09 05:07:25 UTC
Token creation is not thread safe
Hi All,
Token create method in AccessTokenDataBinderImpl[1] is not thread safe.
This could result in several problems including
- Exist 2 different access token for a particular user at a given time
which may result in an exception thrown by method call[2] since it expects
a single token a given user.
In addition to that token replace is implemented as a combination of 2
different functionalities. Since the method is not thread safe this may
cause some unexpected behaviors (since there can be 2 tokens exist for a
particular user. same scenario as above).
Appreciate your insight on the $subject.
[1]
https://github.com/apache/syncope/blob/master/core/provisioning-java/src/main/java/org/apache/syncope/core/provisioning/java/data/AccessTokenDataBinderImpl.java#L104
[2]
https://github.com/apache/syncope/blob/master/core/provisioning-java/src/main/java/org/apache/syncope/core/provisioning/java/data/AccessTokenDataBinderImpl.java#L113
Best Regards
Isuranga Perera
Re: Token creation is not thread safe
Posted by Francesco Chicchiriccò <il...@apache.org>.
On 13/04/2018 09:48, Isuranga Perera wrote:
> Hi Francesco,
>
> Yes, that will fix the problem.
Glad we agree :-)
I'll set SYNCOPE-1301; please close the PR #70.
Regards.
> On Fri, Apr 13, 2018 at 1:00 PM, Francesco Chicchiriccò <ilgrosso@apache.org wrote:
>
>> Hi,
>> after our discussion on PR #70 [1] yesterday, I took the chance to review
>> the AccessToken creation logic and committed a change [2] which should fix
>> your warnings from SYNCOPE-1301.
>>
>> Please, take a look at let me know if we can consider SYNCOPE-1301 as
>> resolved.
>>
>> Regards.
>>
>> [1] https://github.com/apache/syncope/pull/70
>> [2] https://github.com/apache/syncope/commit/24f789932141ee05fa1
>> 2d81eca9d43178953f508
>>
>>
>> On 09/04/2018 13:19, Isuranga Perera wrote:
>>
>>> Sure will work on that. I'll give priority to this feature and will
>>> continue to work on the eclipse project upon the completion of this one.
>>>
>>> Best Regards
>>> Isuranga Perera
>>>
>>> On Mon, Apr 9, 2018 at 4:27 PM, Francesco Chicchiriccò <
>>> ilgrosso@apache.org>
>>> wrote:
>>>
>>> On 09/04/2018 11:24, Isuranga Perera wrote:
>>>> Sure will work on that. Shall I create a JIRA?
>>>>> Yes, please.
>>>> Do set both 2.0.9 and 2.1.0 as fix-for-versions since I will apply your
>>>> PR
>>>> both to branches master and 2_0_X.
>>>>
>>>> Sorry for the delay will submit the ICLA asap
>>>> Ok, thanks.
>>>>
>>>>
>>>> Regards.
>>>>
>>>> On Mon, Apr 9, 2018 at 2:45 PM, Francesco Chicchiriccò <
>>>>
>>>>> ilgrosso@apache.org>
>>>>> wrote:
>>>>>
>>>>> On 09/04/2018 11:10, Isuranga Perera wrote:
>>>>>
>>>>>> Since such condition can happen only if the same user tries to login
>>>>>> from
>>>>>>
>>>>>>> 2
>>>>>>> mediums at the same, this is rarely happen. However that slight chance
>>>>>>> may
>>>>>>> prevent that particular user from login to the system until all or
>>>>>>> all-1
>>>>>>> access tokens are expired.
>>>>>>> Using the UNIQUE constraint will definitely will provide a better
>>>>>>> security
>>>>>>> and furthermore will make the model more meaningful. On the other hand
>>>>>>> this
>>>>>>> will break the token replacing functionality since it first create a
>>>>>>> token
>>>>>>> (at this time there are 2 tokens in the db) and delete the last one.
>>>>>>>
>>>>>>> What I propose is writing a separate query to replace tokens instead
>>>>>>> of
>>>>>>> using save & delete queries separately and furthermore we can use a
>>>>>>> new
>>>>>>> query to save tokens without affecting the UNIQUE constraints so that
>>>>>>> no
>>>>>>> need to mess with threading & @Transactional properties.
>>>>>>>
>>>>>>> If you can come up with a proposal which works with all the supported
>>>>>>>
>>>>>> DBMSes, then please go on.
>>>>>>
>>>>>> As already asked as comment in your recent PR: did you submit an ICLA
>>>>>> for
>>>>>> your contributions? Thanks.
>>>>>>
>>>>>> Regards.
>>>>>>
>>>>>> On Mon, Apr 9, 2018 at 2:06 PM, Francesco Chicchiriccò <
>>>>>>
>>>>>> ilgrosso@apache.org>
>>>>>>> wrote:
>>>>>>>
>>>>>>> On 09/04/2018 10:14, Isuranga Perera wrote:
>>>>>>>
>>>>>>> The Read Committed isolation level ensures that data can only be read
>>>>>>>> by
>>>>>>>>
>>>>>>>> a
>>>>>>>>> transaction if it is in the committed state. It doesn't completely
>>>>>>>>> isolate
>>>>>>>>> this transaction(create) hence some other transaction can still use
>>>>>>>>> this
>>>>>>>>> method which results in the behavior I explained previously. Ideally
>>>>>>>>> If
>>>>>>>>> we're gonna use @Transactional annotation the isolation level should
>>>>>>>>> be
>>>>>>>>> serialized for create operation. Please correct me If I'm wrong.
>>>>>>>>>
>>>>>>>>> I see your point - while I don't completely agree about the
>>>>>>>>> likelihood
>>>>>>>>>
>>>>>>>>> of
>>>>>>>> such race condition to actually happen.
>>>>>>>>
>>>>>>>> At worse, you might end up in having two distinct JWT (Access Tokens)
>>>>>>>> values for a single user, which will anyway be subject to expiration
>>>>>>>> due
>>>>>>>> to
>>>>>>>>
>>>>>>>> https://github.com/apache/syncope/blob/master/core/provision
>>>>>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>>> ng/java/job/ExpiredAccessTokenCleanup.java
>>>>>>>>
>>>>>>>> For additional security, we might want to impose a UNIQUE constraint
>>>>>>>> on
>>>>>>>>
>>>>>>>> https://github.com/apache/syncope/blob/master/core/persisten
>>>>>>>> ce-jpa/src/main/java/org/apache/syncope/core/persistenc
>>>>>>>> e/jpa/entity/JPAAccessToken.java#L48
>>>>>>>>
>>>>>>>> (not sure to remember why the column is currently set as nullable,
>>>>>>>> though).
>>>>>>>> With UNIQUE owner, the step (5) in your sequence below will fail
>>>>>>>> anyway.
>>>>>>>>
>>>>>>>> Again, given the chances that the race condition applies, and
>>>>>>>> considering
>>>>>>>> what would be the harm (nearly none, to me), I would rather avoid any
>>>>>>>> modification rather than imposing the UNIQUE constraint.
>>>>>>>>
>>>>>>>>
>>>>>>>> Regards.
>>>>>>>>
>>>>>>>> On Mon, Apr 9, 2018 at 1:12 PM, Francesco Chicchiriccò <
>>>>>>>>
>>>>>>>> ilgrosso@apache.org>
>>>>>>>>
>>>>>>>>> wrote:
>>>>>>>>>
>>>>>>>>> On 09/04/2018 09:30, Isuranga Perera wrote:
>>>>>>>>>
>>>>>>>>> Hi Francesco,
>>>>>>>>>
>>>>>>>>>> Yes there is @Transactional annotation. But it haven't set the
>>>>>>>>>>
>>>>>>>>>>> isolation
>>>>>>>>>>> property as well as the propagation property. Based on the default
>>>>>>>>>>> values
>>>>>>>>>>> set this thread safe problem will still occur. Please correct me
>>>>>>>>>>> if
>>>>>>>>>>> I'm
>>>>>>>>>>> wrong.
>>>>>>>>>>>
>>>>>>>>>>> The transaction isolation level is set in
>>>>>>>>>>>
>>>>>>>>>>> https://github.com/apache/syncope/blob/master/core/persisten
>>>>>>>>>>>
>>>>>>>>>> ce-jpa/src/main/resources/domains/MasterDomain.xml#L57-L59
>>>>>>>>>>
>>>>>>>>>> Regards.
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> On Mon, Apr 9, 2018 at 12:20 PM, Francesco Chicchiriccò <
>>>>>>>>>>
>>>>>>>>>> ilgrosso@apache.org> wrote:
>>>>>>>>>>
>>>>>>>>>> On 09/04/2018 08:46, Isuranga Perera wrote:
>>>>>>>>>>> Hi Francesco,
>>>>>>>>>>>
>>>>>>>>>>> I will take a scenario. Suppose a scenario where thread A & thread
>>>>>>>>>>>> B
>>>>>>>>>>>>
>>>>>>>>>>>> try
>>>>>>>>>>>>> to login user admin.
>>>>>>>>>>>>>
>>>>>>>>>>>>> 1. thread A checks if a token exist for the user admin
>>>>>>>>>>>>> (suppose
>>>>>>>>>>>>> currently there is no token associated with the admin)
>>>>>>>>>>>>> 2. Then thread A execute following logic[1] to create and
>>>>>>>>>>>>> save
>>>>>>>>>>>>> the
>>>>>>>>>>>>> token.
>>>>>>>>>>>>> 3. Before thread A save the token for user admin thread B
>>>>>>>>>>>>> checks
>>>>>>>>>>>>> if a
>>>>>>>>>>>>> token exist for user admin (since the toked created by
>>>>>>>>>>>>> thread A
>>>>>>>>>>>>> is
>>>>>>>>>>>>> not yet saved *exist == null*)
>>>>>>>>>>>>> 4. Then thread A complete the creation of token (and
>>>>>>>>>>>>> saving)
>>>>>>>>>>>>> 5. Thread B also complete the creation and saving of the
>>>>>>>>>>>>> token.
>>>>>>>>>>>>>
>>>>>>>>>>>>> That way there can be 2 tokens for a particular user.
>>>>>>>>>>>>>
>>>>>>>>>>>>>
>>>>>>>>>>>>> You analysis does not take into any account the fact of the
>>>>>>>>>>>>> constraints
>>>>>>>>>>>>>
>>>>>>>>>>>>> imposed by the @Service annotation in
>>>>>>>>>>>>>
>>>>>>>>>>>>> https://github.com/apache/syncope/blob/master/core/rest-cxf/
>>>>>>>>>>>> src/main/java/org/apache/syncope/core/rest/cxf/service/Acces
>>>>>>>>>>>> sTokenServiceImpl.java#L35
>>>>>>>>>>>>
>>>>>>>>>>>> (e.g. the place when external requests can come in) nor by the
>>>>>>>>>>>> @Transactional annotation injected into
>>>>>>>>>>>>
>>>>>>>>>>>> https://github.com/apache/syncope/blob/master/core/logic/
>>>>>>>>>>>> src/main/java/org/apache/syncope/core/logic/AccessTokenLogic
>>>>>>>>>>>> .java#L80
>>>>>>>>>>>>
>>>>>>>>>>>> via
>>>>>>>>>>>>
>>>>>>>>>>>> https://github.com/apache/syncope/blob/master/core/logic/
>>>>>>>>>>>> src/main/java/org/apache/syncope/core/logic/AbstractTra
>>>>>>>>>>>> nsactionalLogic.java#L29
>>>>>>>>>>>>
>>>>>>>>>>>> Regards.
>>>>>>>>>>>>
>>>>>>>>>>>> [1] https://github.com/apache/syncope/blob/master/core/provision
>>>>>>>>>>>>
>>>>>>>>>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>>>>>>>
>>>>>>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L119
>>>>>>>>>>>>
>>>>>>>>>>>>> Best Regards
>>>>>>>>>>>>> Isuranga Perera
>>>>>>>>>>>>>
>>>>>>>>>>>>> On Mon, Apr 9, 2018 at 11:42 AM, Francesco Chicchiriccò <
>>>>>>>>>>>>> ilgrosso@apache.org <ma...@apache.org>> wrote:
>>>>>>>>>>>>>
>>>>>>>>>>>>> On 09/04/2018 07:07, Isuranga Perera wrote:
>>>>>>>>>>>>>
>>>>>>>>>>>>> Hi All,
>>>>>>>>>>>>>
>>>>>>>>>>>>> Token create method in
>>>>>>>>>>>>> AccessTokenDataBinderImpl[1] is
>>>>>>>>>>>>> not
>>>>>>>>>>>>> thread safe.
>>>>>>>>>>>>>
>>>>>>>>>>>>>
>>>>>>>>>>>>> Could you please explain why you're affirming this?
>>>>>>>>>>>>>
>>>>>>>>>>>>> This could result in several problems including
>>>>>>>>>>>>>
>>>>>>>>>>>>> * Exist 2 different access token for a particular
>>>>>>>>>>>>> user
>>>>>>>>>>>>> at
>>>>>>>>>>>>> a
>>>>>>>>>>>>> given
>>>>>>>>>>>>> time which may result in an exception thrown by
>>>>>>>>>>>>> method
>>>>>>>>>>>>> call[2]
>>>>>>>>>>>>> since it expects a single token a given user.
>>>>>>>>>>>>>
>>>>>>>>>>>>> In addition to that token replace is implemented
>>>>>>>>>>>>> as a
>>>>>>>>>>>>> combination of 2 different functionalities. Since
>>>>>>>>>>>>> the
>>>>>>>>>>>>> method
>>>>>>>>>>>>> is not thread safe this may cause some unexpected
>>>>>>>>>>>>> behaviors
>>>>>>>>>>>>> (since there can be 2 tokens exist for a particular
>>>>>>>>>>>>> user.
>>>>>>>>>>>>> same
>>>>>>>>>>>>> scenario as above).
>>>>>>>>>>>>>
>>>>>>>>>>>>> Appreciate your insight on the $subject.
>>>>>>>>>>>>>
>>>>>>>>>>>>>
>>>>>>>>>>>>> [1]
>>>>>>>>>>>>> https://github.com/apache/sync
>>>>>>>>>>>>> ope/blob/master/core/provision
>>>>>>>>>>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L104
>>>>>>>>>>>>> <https://github.com/apache/syn
>>>>>>>>>>>>> cope/blob/master/core/provisio
>>>>>>>>>>>>> ning-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L104>
>>>>>>>>>>>>>
>>>>>>>>>>>>> [2]
>>>>>>>>>>>>> https://github.com/apache/sync
>>>>>>>>>>>>> ope/blob/master/core/provision
>>>>>>>>>>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L113
>>>>>>>>>>>>> <https://github.com/apache/syn
>>>>>>>>>>>>> cope/blob/master/core/provisio
>>>>>>>>>>>>> ning-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L113>
>>>>>>>>>>>>>
>>>>>>>>>>>>> Best Regards
>>>>>>>>>>>>> Isuranga Perera
>>>>>>>>>>>>>
>> --
>> Francesco Chicchiriccò
>>
>> Tirasa - Open Source Excellence
>> http://www.tirasa.net/
>>
>> Member at The Apache Software Foundation
>> Syncope, Cocoon, Olingo, CXF, OpenJPA, PonyMail
>> http://home.apache.org/~ilgrosso/
>>
>>
--
Francesco Chicchiriccò
Tirasa - Open Source Excellence
http://www.tirasa.net/
Member at The Apache Software Foundation
Syncope, Cocoon, Olingo, CXF, OpenJPA, PonyMail
http://home.apache.org/~ilgrosso/
Re: Token creation is not thread safe
Posted by Isuranga Perera <is...@gmail.com>.
Hi Francesco,
Yes, that will fix the problem.
Best Regards
Isuranga Perera
On Fri, Apr 13, 2018 at 1:00 PM, Francesco Chicchiriccò <ilgrosso@apache.org
> wrote:
> Hi,
> after our discussion on PR #70 [1] yesterday, I took the chance to review
> the AccessToken creation logic and committed a change [2] which should fix
> your warnings from SYNCOPE-1301.
>
> Please, take a look at let me know if we can consider SYNCOPE-1301 as
> resolved.
>
> Regards.
>
> [1] https://github.com/apache/syncope/pull/70
> [2] https://github.com/apache/syncope/commit/24f789932141ee05fa1
> 2d81eca9d43178953f508
>
>
> On 09/04/2018 13:19, Isuranga Perera wrote:
>
>> Sure will work on that. I'll give priority to this feature and will
>> continue to work on the eclipse project upon the completion of this one.
>>
>> Best Regards
>> Isuranga Perera
>>
>> On Mon, Apr 9, 2018 at 4:27 PM, Francesco Chicchiriccò <
>> ilgrosso@apache.org>
>> wrote:
>>
>> On 09/04/2018 11:24, Isuranga Perera wrote:
>>>
>>> Sure will work on that. Shall I create a JIRA?
>>>>
>>>> Yes, please.
>>> Do set both 2.0.9 and 2.1.0 as fix-for-versions since I will apply your
>>> PR
>>> both to branches master and 2_0_X.
>>>
>>> Sorry for the delay will submit the ICLA asap
>>> Ok, thanks.
>>>
>>>
>>> Regards.
>>>
>>> On Mon, Apr 9, 2018 at 2:45 PM, Francesco Chicchiriccò <
>>>
>>>> ilgrosso@apache.org>
>>>> wrote:
>>>>
>>>> On 09/04/2018 11:10, Isuranga Perera wrote:
>>>>
>>>>> Since such condition can happen only if the same user tries to login
>>>>> from
>>>>>
>>>>>> 2
>>>>>> mediums at the same, this is rarely happen. However that slight chance
>>>>>> may
>>>>>> prevent that particular user from login to the system until all or
>>>>>> all-1
>>>>>> access tokens are expired.
>>>>>> Using the UNIQUE constraint will definitely will provide a better
>>>>>> security
>>>>>> and furthermore will make the model more meaningful. On the other hand
>>>>>> this
>>>>>> will break the token replacing functionality since it first create a
>>>>>> token
>>>>>> (at this time there are 2 tokens in the db) and delete the last one.
>>>>>>
>>>>>> What I propose is writing a separate query to replace tokens instead
>>>>>> of
>>>>>> using save & delete queries separately and furthermore we can use a
>>>>>> new
>>>>>> query to save tokens without affecting the UNIQUE constraints so that
>>>>>> no
>>>>>> need to mess with threading & @Transactional properties.
>>>>>>
>>>>>> If you can come up with a proposal which works with all the supported
>>>>>>
>>>>> DBMSes, then please go on.
>>>>>
>>>>> As already asked as comment in your recent PR: did you submit an ICLA
>>>>> for
>>>>> your contributions? Thanks.
>>>>>
>>>>> Regards.
>>>>>
>>>>> On Mon, Apr 9, 2018 at 2:06 PM, Francesco Chicchiriccò <
>>>>>
>>>>> ilgrosso@apache.org>
>>>>>> wrote:
>>>>>>
>>>>>> On 09/04/2018 10:14, Isuranga Perera wrote:
>>>>>>
>>>>>> The Read Committed isolation level ensures that data can only be read
>>>>>>> by
>>>>>>>
>>>>>>> a
>>>>>>>> transaction if it is in the committed state. It doesn't completely
>>>>>>>> isolate
>>>>>>>> this transaction(create) hence some other transaction can still use
>>>>>>>> this
>>>>>>>> method which results in the behavior I explained previously. Ideally
>>>>>>>> If
>>>>>>>> we're gonna use @Transactional annotation the isolation level should
>>>>>>>> be
>>>>>>>> serialized for create operation. Please correct me If I'm wrong.
>>>>>>>>
>>>>>>>> I see your point - while I don't completely agree about the
>>>>>>>> likelihood
>>>>>>>>
>>>>>>>> of
>>>>>>> such race condition to actually happen.
>>>>>>>
>>>>>>> At worse, you might end up in having two distinct JWT (Access Tokens)
>>>>>>> values for a single user, which will anyway be subject to expiration
>>>>>>> due
>>>>>>> to
>>>>>>>
>>>>>>> https://github.com/apache/syncope/blob/master/core/provision
>>>>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>> ng/java/job/ExpiredAccessTokenCleanup.java
>>>>>>>
>>>>>>> For additional security, we might want to impose a UNIQUE constraint
>>>>>>> on
>>>>>>>
>>>>>>> https://github.com/apache/syncope/blob/master/core/persisten
>>>>>>> ce-jpa/src/main/java/org/apache/syncope/core/persistenc
>>>>>>> e/jpa/entity/JPAAccessToken.java#L48
>>>>>>>
>>>>>>> (not sure to remember why the column is currently set as nullable,
>>>>>>> though).
>>>>>>> With UNIQUE owner, the step (5) in your sequence below will fail
>>>>>>> anyway.
>>>>>>>
>>>>>>> Again, given the chances that the race condition applies, and
>>>>>>> considering
>>>>>>> what would be the harm (nearly none, to me), I would rather avoid any
>>>>>>> modification rather than imposing the UNIQUE constraint.
>>>>>>>
>>>>>>>
>>>>>>> Regards.
>>>>>>>
>>>>>>> On Mon, Apr 9, 2018 at 1:12 PM, Francesco Chicchiriccò <
>>>>>>>
>>>>>>> ilgrosso@apache.org>
>>>>>>>
>>>>>>>> wrote:
>>>>>>>>
>>>>>>>> On 09/04/2018 09:30, Isuranga Perera wrote:
>>>>>>>>
>>>>>>>> Hi Francesco,
>>>>>>>>
>>>>>>>>> Yes there is @Transactional annotation. But it haven't set the
>>>>>>>>>
>>>>>>>>>> isolation
>>>>>>>>>> property as well as the propagation property. Based on the default
>>>>>>>>>> values
>>>>>>>>>> set this thread safe problem will still occur. Please correct me
>>>>>>>>>> if
>>>>>>>>>> I'm
>>>>>>>>>> wrong.
>>>>>>>>>>
>>>>>>>>>> The transaction isolation level is set in
>>>>>>>>>>
>>>>>>>>>> https://github.com/apache/syncope/blob/master/core/persisten
>>>>>>>>>>
>>>>>>>>> ce-jpa/src/main/resources/domains/MasterDomain.xml#L57-L59
>>>>>>>>>
>>>>>>>>> Regards.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> On Mon, Apr 9, 2018 at 12:20 PM, Francesco Chicchiriccò <
>>>>>>>>>
>>>>>>>>> ilgrosso@apache.org> wrote:
>>>>>>>>>
>>>>>>>>> On 09/04/2018 08:46, Isuranga Perera wrote:
>>>>>>>>>>
>>>>>>>>>> Hi Francesco,
>>>>>>>>>>
>>>>>>>>>> I will take a scenario. Suppose a scenario where thread A & thread
>>>>>>>>>>> B
>>>>>>>>>>>
>>>>>>>>>>> try
>>>>>>>>>>>> to login user admin.
>>>>>>>>>>>>
>>>>>>>>>>>> 1. thread A checks if a token exist for the user admin
>>>>>>>>>>>> (suppose
>>>>>>>>>>>> currently there is no token associated with the admin)
>>>>>>>>>>>> 2. Then thread A execute following logic[1] to create and
>>>>>>>>>>>> save
>>>>>>>>>>>> the
>>>>>>>>>>>> token.
>>>>>>>>>>>> 3. Before thread A save the token for user admin thread B
>>>>>>>>>>>> checks
>>>>>>>>>>>> if a
>>>>>>>>>>>> token exist for user admin (since the toked created by
>>>>>>>>>>>> thread A
>>>>>>>>>>>> is
>>>>>>>>>>>> not yet saved *exist == null*)
>>>>>>>>>>>> 4. Then thread A complete the creation of token (and
>>>>>>>>>>>> saving)
>>>>>>>>>>>> 5. Thread B also complete the creation and saving of the
>>>>>>>>>>>> token.
>>>>>>>>>>>>
>>>>>>>>>>>> That way there can be 2 tokens for a particular user.
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> You analysis does not take into any account the fact of the
>>>>>>>>>>>> constraints
>>>>>>>>>>>>
>>>>>>>>>>>> imposed by the @Service annotation in
>>>>>>>>>>>>
>>>>>>>>>>>> https://github.com/apache/syncope/blob/master/core/rest-cxf/
>>>>>>>>>>> src/main/java/org/apache/syncope/core/rest/cxf/service/Acces
>>>>>>>>>>> sTokenServiceImpl.java#L35
>>>>>>>>>>>
>>>>>>>>>>> (e.g. the place when external requests can come in) nor by the
>>>>>>>>>>> @Transactional annotation injected into
>>>>>>>>>>>
>>>>>>>>>>> https://github.com/apache/syncope/blob/master/core/logic/
>>>>>>>>>>> src/main/java/org/apache/syncope/core/logic/AccessTokenLogic
>>>>>>>>>>> .java#L80
>>>>>>>>>>>
>>>>>>>>>>> via
>>>>>>>>>>>
>>>>>>>>>>> https://github.com/apache/syncope/blob/master/core/logic/
>>>>>>>>>>> src/main/java/org/apache/syncope/core/logic/AbstractTra
>>>>>>>>>>> nsactionalLogic.java#L29
>>>>>>>>>>>
>>>>>>>>>>> Regards.
>>>>>>>>>>>
>>>>>>>>>>> [1] https://github.com/apache/syncope/blob/master/core/provision
>>>>>>>>>>>
>>>>>>>>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>>>>>>
>>>>>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L119
>>>>>>>>>>>
>>>>>>>>>>>> Best Regards
>>>>>>>>>>>> Isuranga Perera
>>>>>>>>>>>>
>>>>>>>>>>>> On Mon, Apr 9, 2018 at 11:42 AM, Francesco Chicchiriccò <
>>>>>>>>>>>> ilgrosso@apache.org <ma...@apache.org>> wrote:
>>>>>>>>>>>>
>>>>>>>>>>>> On 09/04/2018 07:07, Isuranga Perera wrote:
>>>>>>>>>>>>
>>>>>>>>>>>> Hi All,
>>>>>>>>>>>>
>>>>>>>>>>>> Token create method in
>>>>>>>>>>>> AccessTokenDataBinderImpl[1] is
>>>>>>>>>>>> not
>>>>>>>>>>>> thread safe.
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> Could you please explain why you're affirming this?
>>>>>>>>>>>>
>>>>>>>>>>>> This could result in several problems including
>>>>>>>>>>>>
>>>>>>>>>>>> * Exist 2 different access token for a particular
>>>>>>>>>>>> user
>>>>>>>>>>>> at
>>>>>>>>>>>> a
>>>>>>>>>>>> given
>>>>>>>>>>>> time which may result in an exception thrown by
>>>>>>>>>>>> method
>>>>>>>>>>>> call[2]
>>>>>>>>>>>> since it expects a single token a given user.
>>>>>>>>>>>>
>>>>>>>>>>>> In addition to that token replace is implemented
>>>>>>>>>>>> as a
>>>>>>>>>>>> combination of 2 different functionalities. Since
>>>>>>>>>>>> the
>>>>>>>>>>>> method
>>>>>>>>>>>> is not thread safe this may cause some unexpected
>>>>>>>>>>>> behaviors
>>>>>>>>>>>> (since there can be 2 tokens exist for a particular
>>>>>>>>>>>> user.
>>>>>>>>>>>> same
>>>>>>>>>>>> scenario as above).
>>>>>>>>>>>>
>>>>>>>>>>>> Appreciate your insight on the $subject.
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> [1]
>>>>>>>>>>>> https://github.com/apache/sync
>>>>>>>>>>>> ope/blob/master/core/provision
>>>>>>>>>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L104
>>>>>>>>>>>> <https://github.com/apache/syn
>>>>>>>>>>>> cope/blob/master/core/provisio
>>>>>>>>>>>> ning-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L104>
>>>>>>>>>>>>
>>>>>>>>>>>> [2]
>>>>>>>>>>>> https://github.com/apache/sync
>>>>>>>>>>>> ope/blob/master/core/provision
>>>>>>>>>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L113
>>>>>>>>>>>> <https://github.com/apache/syn
>>>>>>>>>>>> cope/blob/master/core/provisio
>>>>>>>>>>>> ning-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L113>
>>>>>>>>>>>>
>>>>>>>>>>>> Best Regards
>>>>>>>>>>>> Isuranga Perera
>>>>>>>>>>>>
>>>>>>>>>>>
> --
> Francesco Chicchiriccò
>
> Tirasa - Open Source Excellence
> http://www.tirasa.net/
>
> Member at The Apache Software Foundation
> Syncope, Cocoon, Olingo, CXF, OpenJPA, PonyMail
> http://home.apache.org/~ilgrosso/
>
>
Re: Token creation is not thread safe
Posted by Francesco Chicchiriccò <il...@apache.org>.
Hi,
after our discussion on PR #70 [1] yesterday, I took the chance to
review the AccessToken creation logic and committed a change [2] which
should fix your warnings from SYNCOPE-1301.
Please, take a look at let me know if we can consider SYNCOPE-1301 as
resolved.
Regards.
[1] https://github.com/apache/syncope/pull/70
[2]
https://github.com/apache/syncope/commit/24f789932141ee05fa12d81eca9d43178953f508
On 09/04/2018 13:19, Isuranga Perera wrote:
> Sure will work on that. I'll give priority to this feature and will
> continue to work on the eclipse project upon the completion of this one.
>
> Best Regards
> Isuranga Perera
>
> On Mon, Apr 9, 2018 at 4:27 PM, Francesco Chicchiriccò <il...@apache.org>
> wrote:
>
>> On 09/04/2018 11:24, Isuranga Perera wrote:
>>
>>> Sure will work on that. Shall I create a JIRA?
>>>
>> Yes, please.
>> Do set both 2.0.9 and 2.1.0 as fix-for-versions since I will apply your PR
>> both to branches master and 2_0_X.
>>
>> Sorry for the delay will submit the ICLA asap
>> Ok, thanks.
>>
>>
>> Regards.
>>
>> On Mon, Apr 9, 2018 at 2:45 PM, Francesco Chicchiriccò <
>>> ilgrosso@apache.org>
>>> wrote:
>>>
>>> On 09/04/2018 11:10, Isuranga Perera wrote:
>>>> Since such condition can happen only if the same user tries to login from
>>>>> 2
>>>>> mediums at the same, this is rarely happen. However that slight chance
>>>>> may
>>>>> prevent that particular user from login to the system until all or all-1
>>>>> access tokens are expired.
>>>>> Using the UNIQUE constraint will definitely will provide a better
>>>>> security
>>>>> and furthermore will make the model more meaningful. On the other hand
>>>>> this
>>>>> will break the token replacing functionality since it first create a
>>>>> token
>>>>> (at this time there are 2 tokens in the db) and delete the last one.
>>>>>
>>>>> What I propose is writing a separate query to replace tokens instead of
>>>>> using save & delete queries separately and furthermore we can use a new
>>>>> query to save tokens without affecting the UNIQUE constraints so that no
>>>>> need to mess with threading & @Transactional properties.
>>>>>
>>>>> If you can come up with a proposal which works with all the supported
>>>> DBMSes, then please go on.
>>>>
>>>> As already asked as comment in your recent PR: did you submit an ICLA for
>>>> your contributions? Thanks.
>>>>
>>>> Regards.
>>>>
>>>> On Mon, Apr 9, 2018 at 2:06 PM, Francesco Chicchiriccò <
>>>>
>>>>> ilgrosso@apache.org>
>>>>> wrote:
>>>>>
>>>>> On 09/04/2018 10:14, Isuranga Perera wrote:
>>>>>
>>>>>> The Read Committed isolation level ensures that data can only be read
>>>>>> by
>>>>>>
>>>>>>> a
>>>>>>> transaction if it is in the committed state. It doesn't completely
>>>>>>> isolate
>>>>>>> this transaction(create) hence some other transaction can still use
>>>>>>> this
>>>>>>> method which results in the behavior I explained previously. Ideally
>>>>>>> If
>>>>>>> we're gonna use @Transactional annotation the isolation level should
>>>>>>> be
>>>>>>> serialized for create operation. Please correct me If I'm wrong.
>>>>>>>
>>>>>>> I see your point - while I don't completely agree about the likelihood
>>>>>>>
>>>>>> of
>>>>>> such race condition to actually happen.
>>>>>>
>>>>>> At worse, you might end up in having two distinct JWT (Access Tokens)
>>>>>> values for a single user, which will anyway be subject to expiration
>>>>>> due
>>>>>> to
>>>>>>
>>>>>> https://github.com/apache/syncope/blob/master/core/provision
>>>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>> ng/java/job/ExpiredAccessTokenCleanup.java
>>>>>>
>>>>>> For additional security, we might want to impose a UNIQUE constraint on
>>>>>>
>>>>>> https://github.com/apache/syncope/blob/master/core/persisten
>>>>>> ce-jpa/src/main/java/org/apache/syncope/core/persistenc
>>>>>> e/jpa/entity/JPAAccessToken.java#L48
>>>>>>
>>>>>> (not sure to remember why the column is currently set as nullable,
>>>>>> though).
>>>>>> With UNIQUE owner, the step (5) in your sequence below will fail
>>>>>> anyway.
>>>>>>
>>>>>> Again, given the chances that the race condition applies, and
>>>>>> considering
>>>>>> what would be the harm (nearly none, to me), I would rather avoid any
>>>>>> modification rather than imposing the UNIQUE constraint.
>>>>>>
>>>>>>
>>>>>> Regards.
>>>>>>
>>>>>> On Mon, Apr 9, 2018 at 1:12 PM, Francesco Chicchiriccò <
>>>>>>
>>>>>> ilgrosso@apache.org>
>>>>>>> wrote:
>>>>>>>
>>>>>>> On 09/04/2018 09:30, Isuranga Perera wrote:
>>>>>>>
>>>>>>> Hi Francesco,
>>>>>>>> Yes there is @Transactional annotation. But it haven't set the
>>>>>>>>> isolation
>>>>>>>>> property as well as the propagation property. Based on the default
>>>>>>>>> values
>>>>>>>>> set this thread safe problem will still occur. Please correct me if
>>>>>>>>> I'm
>>>>>>>>> wrong.
>>>>>>>>>
>>>>>>>>> The transaction isolation level is set in
>>>>>>>>>
>>>>>>>>> https://github.com/apache/syncope/blob/master/core/persisten
>>>>>>>> ce-jpa/src/main/resources/domains/MasterDomain.xml#L57-L59
>>>>>>>>
>>>>>>>> Regards.
>>>>>>>>
>>>>>>>>
>>>>>>>> On Mon, Apr 9, 2018 at 12:20 PM, Francesco Chicchiriccò <
>>>>>>>>
>>>>>>>> ilgrosso@apache.org> wrote:
>>>>>>>>
>>>>>>>>> On 09/04/2018 08:46, Isuranga Perera wrote:
>>>>>>>>>
>>>>>>>>> Hi Francesco,
>>>>>>>>>
>>>>>>>>>> I will take a scenario. Suppose a scenario where thread A & thread
>>>>>>>>>> B
>>>>>>>>>>
>>>>>>>>>>> try
>>>>>>>>>>> to login user admin.
>>>>>>>>>>>
>>>>>>>>>>> 1. thread A checks if a token exist for the user admin
>>>>>>>>>>> (suppose
>>>>>>>>>>> currently there is no token associated with the admin)
>>>>>>>>>>> 2. Then thread A execute following logic[1] to create and
>>>>>>>>>>> save
>>>>>>>>>>> the
>>>>>>>>>>> token.
>>>>>>>>>>> 3. Before thread A save the token for user admin thread B
>>>>>>>>>>> checks
>>>>>>>>>>> if a
>>>>>>>>>>> token exist for user admin (since the toked created by
>>>>>>>>>>> thread A
>>>>>>>>>>> is
>>>>>>>>>>> not yet saved *exist == null*)
>>>>>>>>>>> 4. Then thread A complete the creation of token (and saving)
>>>>>>>>>>> 5. Thread B also complete the creation and saving of the
>>>>>>>>>>> token.
>>>>>>>>>>>
>>>>>>>>>>> That way there can be 2 tokens for a particular user.
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> You analysis does not take into any account the fact of the
>>>>>>>>>>> constraints
>>>>>>>>>>>
>>>>>>>>>>> imposed by the @Service annotation in
>>>>>>>>>>>
>>>>>>>>>> https://github.com/apache/syncope/blob/master/core/rest-cxf/
>>>>>>>>>> src/main/java/org/apache/syncope/core/rest/cxf/service/Acces
>>>>>>>>>> sTokenServiceImpl.java#L35
>>>>>>>>>>
>>>>>>>>>> (e.g. the place when external requests can come in) nor by the
>>>>>>>>>> @Transactional annotation injected into
>>>>>>>>>>
>>>>>>>>>> https://github.com/apache/syncope/blob/master/core/logic/
>>>>>>>>>> src/main/java/org/apache/syncope/core/logic/AccessTokenLogic
>>>>>>>>>> .java#L80
>>>>>>>>>>
>>>>>>>>>> via
>>>>>>>>>>
>>>>>>>>>> https://github.com/apache/syncope/blob/master/core/logic/
>>>>>>>>>> src/main/java/org/apache/syncope/core/logic/AbstractTra
>>>>>>>>>> nsactionalLogic.java#L29
>>>>>>>>>>
>>>>>>>>>> Regards.
>>>>>>>>>>
>>>>>>>>>> [1] https://github.com/apache/syncope/blob/master/core/provision
>>>>>>>>>>
>>>>>>>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>>>>>
>>>>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L119
>>>>>>>>>>> Best Regards
>>>>>>>>>>> Isuranga Perera
>>>>>>>>>>>
>>>>>>>>>>> On Mon, Apr 9, 2018 at 11:42 AM, Francesco Chicchiriccò <
>>>>>>>>>>> ilgrosso@apache.org <ma...@apache.org>> wrote:
>>>>>>>>>>>
>>>>>>>>>>> On 09/04/2018 07:07, Isuranga Perera wrote:
>>>>>>>>>>>
>>>>>>>>>>> Hi All,
>>>>>>>>>>>
>>>>>>>>>>> Token create method in AccessTokenDataBinderImpl[1] is
>>>>>>>>>>> not
>>>>>>>>>>> thread safe.
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> Could you please explain why you're affirming this?
>>>>>>>>>>>
>>>>>>>>>>> This could result in several problems including
>>>>>>>>>>>
>>>>>>>>>>> * Exist 2 different access token for a particular
>>>>>>>>>>> user
>>>>>>>>>>> at
>>>>>>>>>>> a
>>>>>>>>>>> given
>>>>>>>>>>> time which may result in an exception thrown by
>>>>>>>>>>> method
>>>>>>>>>>> call[2]
>>>>>>>>>>> since it expects a single token a given user.
>>>>>>>>>>>
>>>>>>>>>>> In addition to that token replace is implemented as a
>>>>>>>>>>> combination of 2 different functionalities. Since the
>>>>>>>>>>> method
>>>>>>>>>>> is not thread safe this may cause some unexpected
>>>>>>>>>>> behaviors
>>>>>>>>>>> (since there can be 2 tokens exist for a particular
>>>>>>>>>>> user.
>>>>>>>>>>> same
>>>>>>>>>>> scenario as above).
>>>>>>>>>>>
>>>>>>>>>>> Appreciate your insight on the $subject.
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> [1]
>>>>>>>>>>> https://github.com/apache/sync
>>>>>>>>>>> ope/blob/master/core/provision
>>>>>>>>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L104
>>>>>>>>>>> <https://github.com/apache/syn
>>>>>>>>>>> cope/blob/master/core/provisio
>>>>>>>>>>> ning-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L104>
>>>>>>>>>>>
>>>>>>>>>>> [2]
>>>>>>>>>>> https://github.com/apache/sync
>>>>>>>>>>> ope/blob/master/core/provision
>>>>>>>>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L113
>>>>>>>>>>> <https://github.com/apache/syn
>>>>>>>>>>> cope/blob/master/core/provisio
>>>>>>>>>>> ning-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L113>
>>>>>>>>>>>
>>>>>>>>>>> Best Regards
>>>>>>>>>>> Isuranga Perera
--
Francesco Chicchiriccò
Tirasa - Open Source Excellence
http://www.tirasa.net/
Member at The Apache Software Foundation
Syncope, Cocoon, Olingo, CXF, OpenJPA, PonyMail
http://home.apache.org/~ilgrosso/
Re: Token creation is not thread safe
Posted by Isuranga Perera <is...@gmail.com>.
Sure will work on that. I'll give priority to this feature and will
continue to work on the eclipse project upon the completion of this one.
Best Regards
Isuranga Perera
On Mon, Apr 9, 2018 at 4:27 PM, Francesco Chicchiriccò <il...@apache.org>
wrote:
> On 09/04/2018 11:24, Isuranga Perera wrote:
>
>> Sure will work on that. Shall I create a JIRA?
>>
>
> Yes, please.
> Do set both 2.0.9 and 2.1.0 as fix-for-versions since I will apply your PR
> both to branches master and 2_0_X.
>
> Sorry for the delay will submit the ICLA asap
>>
>
> Ok, thanks.
>
>
> Regards.
>
> On Mon, Apr 9, 2018 at 2:45 PM, Francesco Chicchiriccò <
>> ilgrosso@apache.org>
>> wrote:
>>
>> On 09/04/2018 11:10, Isuranga Perera wrote:
>>>
>>> Since such condition can happen only if the same user tries to login from
>>>> 2
>>>> mediums at the same, this is rarely happen. However that slight chance
>>>> may
>>>> prevent that particular user from login to the system until all or all-1
>>>> access tokens are expired.
>>>> Using the UNIQUE constraint will definitely will provide a better
>>>> security
>>>> and furthermore will make the model more meaningful. On the other hand
>>>> this
>>>> will break the token replacing functionality since it first create a
>>>> token
>>>> (at this time there are 2 tokens in the db) and delete the last one.
>>>>
>>>> What I propose is writing a separate query to replace tokens instead of
>>>> using save & delete queries separately and furthermore we can use a new
>>>> query to save tokens without affecting the UNIQUE constraints so that no
>>>> need to mess with threading & @Transactional properties.
>>>>
>>>> If you can come up with a proposal which works with all the supported
>>> DBMSes, then please go on.
>>>
>>> As already asked as comment in your recent PR: did you submit an ICLA for
>>> your contributions? Thanks.
>>>
>>> Regards.
>>>
>>> On Mon, Apr 9, 2018 at 2:06 PM, Francesco Chicchiriccò <
>>>
>>>> ilgrosso@apache.org>
>>>> wrote:
>>>>
>>>> On 09/04/2018 10:14, Isuranga Perera wrote:
>>>>
>>>>> The Read Committed isolation level ensures that data can only be read
>>>>> by
>>>>>
>>>>>> a
>>>>>> transaction if it is in the committed state. It doesn't completely
>>>>>> isolate
>>>>>> this transaction(create) hence some other transaction can still use
>>>>>> this
>>>>>> method which results in the behavior I explained previously. Ideally
>>>>>> If
>>>>>> we're gonna use @Transactional annotation the isolation level should
>>>>>> be
>>>>>> serialized for create operation. Please correct me If I'm wrong.
>>>>>>
>>>>>> I see your point - while I don't completely agree about the likelihood
>>>>>>
>>>>> of
>>>>> such race condition to actually happen.
>>>>>
>>>>> At worse, you might end up in having two distinct JWT (Access Tokens)
>>>>> values for a single user, which will anyway be subject to expiration
>>>>> due
>>>>> to
>>>>>
>>>>> https://github.com/apache/syncope/blob/master/core/provision
>>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>>> ng/java/job/ExpiredAccessTokenCleanup.java
>>>>>
>>>>> For additional security, we might want to impose a UNIQUE constraint on
>>>>>
>>>>> https://github.com/apache/syncope/blob/master/core/persisten
>>>>> ce-jpa/src/main/java/org/apache/syncope/core/persistenc
>>>>> e/jpa/entity/JPAAccessToken.java#L48
>>>>>
>>>>> (not sure to remember why the column is currently set as nullable,
>>>>> though).
>>>>> With UNIQUE owner, the step (5) in your sequence below will fail
>>>>> anyway.
>>>>>
>>>>> Again, given the chances that the race condition applies, and
>>>>> considering
>>>>> what would be the harm (nearly none, to me), I would rather avoid any
>>>>> modification rather than imposing the UNIQUE constraint.
>>>>>
>>>>>
>>>>> Regards.
>>>>>
>>>>> On Mon, Apr 9, 2018 at 1:12 PM, Francesco Chicchiriccò <
>>>>>
>>>>> ilgrosso@apache.org>
>>>>>> wrote:
>>>>>>
>>>>>> On 09/04/2018 09:30, Isuranga Perera wrote:
>>>>>>
>>>>>> Hi Francesco,
>>>>>>>
>>>>>>> Yes there is @Transactional annotation. But it haven't set the
>>>>>>>> isolation
>>>>>>>> property as well as the propagation property. Based on the default
>>>>>>>> values
>>>>>>>> set this thread safe problem will still occur. Please correct me if
>>>>>>>> I'm
>>>>>>>> wrong.
>>>>>>>>
>>>>>>>> The transaction isolation level is set in
>>>>>>>>
>>>>>>>> https://github.com/apache/syncope/blob/master/core/persisten
>>>>>>> ce-jpa/src/main/resources/domains/MasterDomain.xml#L57-L59
>>>>>>>
>>>>>>> Regards.
>>>>>>>
>>>>>>>
>>>>>>> On Mon, Apr 9, 2018 at 12:20 PM, Francesco Chicchiriccò <
>>>>>>>
>>>>>>> ilgrosso@apache.org> wrote:
>>>>>>>
>>>>>>>> On 09/04/2018 08:46, Isuranga Perera wrote:
>>>>>>>>
>>>>>>>> Hi Francesco,
>>>>>>>>
>>>>>>>>> I will take a scenario. Suppose a scenario where thread A & thread
>>>>>>>>> B
>>>>>>>>>
>>>>>>>>>> try
>>>>>>>>>> to login user admin.
>>>>>>>>>>
>>>>>>>>>> 1. thread A checks if a token exist for the user admin
>>>>>>>>>> (suppose
>>>>>>>>>> currently there is no token associated with the admin)
>>>>>>>>>> 2. Then thread A execute following logic[1] to create and
>>>>>>>>>> save
>>>>>>>>>> the
>>>>>>>>>> token.
>>>>>>>>>> 3. Before thread A save the token for user admin thread B
>>>>>>>>>> checks
>>>>>>>>>> if a
>>>>>>>>>> token exist for user admin (since the toked created by
>>>>>>>>>> thread A
>>>>>>>>>> is
>>>>>>>>>> not yet saved *exist == null*)
>>>>>>>>>> 4. Then thread A complete the creation of token (and saving)
>>>>>>>>>> 5. Thread B also complete the creation and saving of the
>>>>>>>>>> token.
>>>>>>>>>>
>>>>>>>>>> That way there can be 2 tokens for a particular user.
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> You analysis does not take into any account the fact of the
>>>>>>>>>> constraints
>>>>>>>>>>
>>>>>>>>>> imposed by the @Service annotation in
>>>>>>>>>>
>>>>>>>>> https://github.com/apache/syncope/blob/master/core/rest-cxf/
>>>>>>>>> src/main/java/org/apache/syncope/core/rest/cxf/service/Acces
>>>>>>>>> sTokenServiceImpl.java#L35
>>>>>>>>>
>>>>>>>>> (e.g. the place when external requests can come in) nor by the
>>>>>>>>> @Transactional annotation injected into
>>>>>>>>>
>>>>>>>>> https://github.com/apache/syncope/blob/master/core/logic/
>>>>>>>>> src/main/java/org/apache/syncope/core/logic/AccessTokenLogic
>>>>>>>>> .java#L80
>>>>>>>>>
>>>>>>>>> via
>>>>>>>>>
>>>>>>>>> https://github.com/apache/syncope/blob/master/core/logic/
>>>>>>>>> src/main/java/org/apache/syncope/core/logic/AbstractTra
>>>>>>>>> nsactionalLogic.java#L29
>>>>>>>>>
>>>>>>>>> Regards.
>>>>>>>>>
>>>>>>>>> [1] https://github.com/apache/syncope/blob/master/core/provision
>>>>>>>>>
>>>>>>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>>>>
>>>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L119
>>>>>>>>>>
>>>>>>>>>> Best Regards
>>>>>>>>>> Isuranga Perera
>>>>>>>>>>
>>>>>>>>>> On Mon, Apr 9, 2018 at 11:42 AM, Francesco Chicchiriccò <
>>>>>>>>>> ilgrosso@apache.org <ma...@apache.org>> wrote:
>>>>>>>>>>
>>>>>>>>>> On 09/04/2018 07:07, Isuranga Perera wrote:
>>>>>>>>>>
>>>>>>>>>> Hi All,
>>>>>>>>>>
>>>>>>>>>> Token create method in AccessTokenDataBinderImpl[1] is
>>>>>>>>>> not
>>>>>>>>>> thread safe.
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> Could you please explain why you're affirming this?
>>>>>>>>>>
>>>>>>>>>> This could result in several problems including
>>>>>>>>>>
>>>>>>>>>> * Exist 2 different access token for a particular
>>>>>>>>>> user
>>>>>>>>>> at
>>>>>>>>>> a
>>>>>>>>>> given
>>>>>>>>>> time which may result in an exception thrown by
>>>>>>>>>> method
>>>>>>>>>> call[2]
>>>>>>>>>> since it expects a single token a given user.
>>>>>>>>>>
>>>>>>>>>> In addition to that token replace is implemented as a
>>>>>>>>>> combination of 2 different functionalities. Since the
>>>>>>>>>> method
>>>>>>>>>> is not thread safe this may cause some unexpected
>>>>>>>>>> behaviors
>>>>>>>>>> (since there can be 2 tokens exist for a particular
>>>>>>>>>> user.
>>>>>>>>>> same
>>>>>>>>>> scenario as above).
>>>>>>>>>>
>>>>>>>>>> Appreciate your insight on the $subject.
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> [1]
>>>>>>>>>> https://github.com/apache/sync
>>>>>>>>>> ope/blob/master/core/provision
>>>>>>>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L104
>>>>>>>>>> <https://github.com/apache/syn
>>>>>>>>>> cope/blob/master/core/provisio
>>>>>>>>>> ning-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L104>
>>>>>>>>>>
>>>>>>>>>> [2]
>>>>>>>>>> https://github.com/apache/sync
>>>>>>>>>> ope/blob/master/core/provision
>>>>>>>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L113
>>>>>>>>>> <https://github.com/apache/syn
>>>>>>>>>> cope/blob/master/core/provisio
>>>>>>>>>> ning-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L113>
>>>>>>>>>>
>>>>>>>>>> Best Regards
>>>>>>>>>> Isuranga Perera
>>>>>>>>>>
>>>>>>>>>
>
> --
> Francesco Chicchiriccò
>
> Tirasa - Open Source Excellence
> http://www.tirasa.net/
>
> Member at The Apache Software Foundation
> Syncope, Cocoon, Olingo, CXF, OpenJPA, PonyMail
> http://home.apache.org/~ilgrosso/
>
>
Re: Token creation is not thread safe
Posted by Francesco Chicchiriccò <il...@apache.org>.
On 09/04/2018 11:24, Isuranga Perera wrote:
> Sure will work on that. Shall I create a JIRA?
Yes, please.
Do set both 2.0.9 and 2.1.0 as fix-for-versions since I will apply your
PR both to branches master and 2_0_X.
> Sorry for the delay will submit the ICLA asap
Ok, thanks.
Regards.
> On Mon, Apr 9, 2018 at 2:45 PM, Francesco Chicchiriccò <il...@apache.org>
> wrote:
>
>> On 09/04/2018 11:10, Isuranga Perera wrote:
>>
>>> Since such condition can happen only if the same user tries to login from
>>> 2
>>> mediums at the same, this is rarely happen. However that slight chance may
>>> prevent that particular user from login to the system until all or all-1
>>> access tokens are expired.
>>> Using the UNIQUE constraint will definitely will provide a better security
>>> and furthermore will make the model more meaningful. On the other hand
>>> this
>>> will break the token replacing functionality since it first create a token
>>> (at this time there are 2 tokens in the db) and delete the last one.
>>>
>>> What I propose is writing a separate query to replace tokens instead of
>>> using save & delete queries separately and furthermore we can use a new
>>> query to save tokens without affecting the UNIQUE constraints so that no
>>> need to mess with threading & @Transactional properties.
>>>
>> If you can come up with a proposal which works with all the supported
>> DBMSes, then please go on.
>>
>> As already asked as comment in your recent PR: did you submit an ICLA for
>> your contributions? Thanks.
>>
>> Regards.
>>
>> On Mon, Apr 9, 2018 at 2:06 PM, Francesco Chicchiriccò <
>>> ilgrosso@apache.org>
>>> wrote:
>>>
>>> On 09/04/2018 10:14, Isuranga Perera wrote:
>>>> The Read Committed isolation level ensures that data can only be read by
>>>>> a
>>>>> transaction if it is in the committed state. It doesn't completely
>>>>> isolate
>>>>> this transaction(create) hence some other transaction can still use this
>>>>> method which results in the behavior I explained previously. Ideally If
>>>>> we're gonna use @Transactional annotation the isolation level should be
>>>>> serialized for create operation. Please correct me If I'm wrong.
>>>>>
>>>>> I see your point - while I don't completely agree about the likelihood
>>>> of
>>>> such race condition to actually happen.
>>>>
>>>> At worse, you might end up in having two distinct JWT (Access Tokens)
>>>> values for a single user, which will anyway be subject to expiration due
>>>> to
>>>>
>>>> https://github.com/apache/syncope/blob/master/core/provision
>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>> ng/java/job/ExpiredAccessTokenCleanup.java
>>>>
>>>> For additional security, we might want to impose a UNIQUE constraint on
>>>>
>>>> https://github.com/apache/syncope/blob/master/core/persisten
>>>> ce-jpa/src/main/java/org/apache/syncope/core/persistenc
>>>> e/jpa/entity/JPAAccessToken.java#L48
>>>>
>>>> (not sure to remember why the column is currently set as nullable,
>>>> though).
>>>> With UNIQUE owner, the step (5) in your sequence below will fail anyway.
>>>>
>>>> Again, given the chances that the race condition applies, and considering
>>>> what would be the harm (nearly none, to me), I would rather avoid any
>>>> modification rather than imposing the UNIQUE constraint.
>>>>
>>>>
>>>> Regards.
>>>>
>>>> On Mon, Apr 9, 2018 at 1:12 PM, Francesco Chicchiriccò <
>>>>
>>>>> ilgrosso@apache.org>
>>>>> wrote:
>>>>>
>>>>> On 09/04/2018 09:30, Isuranga Perera wrote:
>>>>>
>>>>>> Hi Francesco,
>>>>>>
>>>>>>> Yes there is @Transactional annotation. But it haven't set the
>>>>>>> isolation
>>>>>>> property as well as the propagation property. Based on the default
>>>>>>> values
>>>>>>> set this thread safe problem will still occur. Please correct me if
>>>>>>> I'm
>>>>>>> wrong.
>>>>>>>
>>>>>>> The transaction isolation level is set in
>>>>>>>
>>>>>> https://github.com/apache/syncope/blob/master/core/persisten
>>>>>> ce-jpa/src/main/resources/domains/MasterDomain.xml#L57-L59
>>>>>>
>>>>>> Regards.
>>>>>>
>>>>>>
>>>>>> On Mon, Apr 9, 2018 at 12:20 PM, Francesco Chicchiriccò <
>>>>>>
>>>>>> ilgrosso@apache.org> wrote:
>>>>>>> On 09/04/2018 08:46, Isuranga Perera wrote:
>>>>>>>
>>>>>>> Hi Francesco,
>>>>>>>> I will take a scenario. Suppose a scenario where thread A & thread B
>>>>>>>>> try
>>>>>>>>> to login user admin.
>>>>>>>>>
>>>>>>>>> 1. thread A checks if a token exist for the user admin (suppose
>>>>>>>>> currently there is no token associated with the admin)
>>>>>>>>> 2. Then thread A execute following logic[1] to create and save
>>>>>>>>> the
>>>>>>>>> token.
>>>>>>>>> 3. Before thread A save the token for user admin thread B checks
>>>>>>>>> if a
>>>>>>>>> token exist for user admin (since the toked created by
>>>>>>>>> thread A
>>>>>>>>> is
>>>>>>>>> not yet saved *exist == null*)
>>>>>>>>> 4. Then thread A complete the creation of token (and saving)
>>>>>>>>> 5. Thread B also complete the creation and saving of the token.
>>>>>>>>>
>>>>>>>>> That way there can be 2 tokens for a particular user.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> You analysis does not take into any account the fact of the
>>>>>>>>> constraints
>>>>>>>>>
>>>>>>>>> imposed by the @Service annotation in
>>>>>>>> https://github.com/apache/syncope/blob/master/core/rest-cxf/
>>>>>>>> src/main/java/org/apache/syncope/core/rest/cxf/service/Acces
>>>>>>>> sTokenServiceImpl.java#L35
>>>>>>>>
>>>>>>>> (e.g. the place when external requests can come in) nor by the
>>>>>>>> @Transactional annotation injected into
>>>>>>>>
>>>>>>>> https://github.com/apache/syncope/blob/master/core/logic/
>>>>>>>> src/main/java/org/apache/syncope/core/logic/AccessTokenLogic
>>>>>>>> .java#L80
>>>>>>>>
>>>>>>>> via
>>>>>>>>
>>>>>>>> https://github.com/apache/syncope/blob/master/core/logic/
>>>>>>>> src/main/java/org/apache/syncope/core/logic/AbstractTra
>>>>>>>> nsactionalLogic.java#L29
>>>>>>>>
>>>>>>>> Regards.
>>>>>>>>
>>>>>>>> [1] https://github.com/apache/syncope/blob/master/core/provision
>>>>>>>>
>>>>>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>>>
>>>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L119
>>>>>>>>>
>>>>>>>>> Best Regards
>>>>>>>>> Isuranga Perera
>>>>>>>>>
>>>>>>>>> On Mon, Apr 9, 2018 at 11:42 AM, Francesco Chicchiriccò <
>>>>>>>>> ilgrosso@apache.org <ma...@apache.org>> wrote:
>>>>>>>>>
>>>>>>>>> On 09/04/2018 07:07, Isuranga Perera wrote:
>>>>>>>>>
>>>>>>>>> Hi All,
>>>>>>>>>
>>>>>>>>> Token create method in AccessTokenDataBinderImpl[1] is
>>>>>>>>> not
>>>>>>>>> thread safe.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Could you please explain why you're affirming this?
>>>>>>>>>
>>>>>>>>> This could result in several problems including
>>>>>>>>>
>>>>>>>>> * Exist 2 different access token for a particular user
>>>>>>>>> at
>>>>>>>>> a
>>>>>>>>> given
>>>>>>>>> time which may result in an exception thrown by
>>>>>>>>> method
>>>>>>>>> call[2]
>>>>>>>>> since it expects a single token a given user.
>>>>>>>>>
>>>>>>>>> In addition to that token replace is implemented as a
>>>>>>>>> combination of 2 different functionalities. Since the
>>>>>>>>> method
>>>>>>>>> is not thread safe this may cause some unexpected
>>>>>>>>> behaviors
>>>>>>>>> (since there can be 2 tokens exist for a particular user.
>>>>>>>>> same
>>>>>>>>> scenario as above).
>>>>>>>>>
>>>>>>>>> Appreciate your insight on the $subject.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> [1]
>>>>>>>>> https://github.com/apache/sync
>>>>>>>>> ope/blob/master/core/provision
>>>>>>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L104
>>>>>>>>> <https://github.com/apache/syn
>>>>>>>>> cope/blob/master/core/provisio
>>>>>>>>> ning-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L104>
>>>>>>>>>
>>>>>>>>> [2]
>>>>>>>>> https://github.com/apache/sync
>>>>>>>>> ope/blob/master/core/provision
>>>>>>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L113
>>>>>>>>> <https://github.com/apache/syn
>>>>>>>>> cope/blob/master/core/provisio
>>>>>>>>> ning-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L113>
>>>>>>>>>
>>>>>>>>> Best Regards
>>>>>>>>> Isuranga Perera
--
Francesco Chicchiriccò
Tirasa - Open Source Excellence
http://www.tirasa.net/
Member at The Apache Software Foundation
Syncope, Cocoon, Olingo, CXF, OpenJPA, PonyMail
http://home.apache.org/~ilgrosso/
Re: Token creation is not thread safe
Posted by Isuranga Perera <is...@gmail.com>.
Sure will work on that. Shall I create a JIRA?
Sorry for the delay will submit the ICLA asap
Best Regards
Isuranga Perera
On Mon, Apr 9, 2018 at 2:45 PM, Francesco Chicchiriccò <il...@apache.org>
wrote:
> On 09/04/2018 11:10, Isuranga Perera wrote:
>
>> Since such condition can happen only if the same user tries to login from
>> 2
>> mediums at the same, this is rarely happen. However that slight chance may
>> prevent that particular user from login to the system until all or all-1
>> access tokens are expired.
>> Using the UNIQUE constraint will definitely will provide a better security
>> and furthermore will make the model more meaningful. On the other hand
>> this
>> will break the token replacing functionality since it first create a token
>> (at this time there are 2 tokens in the db) and delete the last one.
>>
>> What I propose is writing a separate query to replace tokens instead of
>> using save & delete queries separately and furthermore we can use a new
>> query to save tokens without affecting the UNIQUE constraints so that no
>> need to mess with threading & @Transactional properties.
>>
>
> If you can come up with a proposal which works with all the supported
> DBMSes, then please go on.
>
> As already asked as comment in your recent PR: did you submit an ICLA for
> your contributions? Thanks.
>
> Regards.
>
> On Mon, Apr 9, 2018 at 2:06 PM, Francesco Chicchiriccò <
>> ilgrosso@apache.org>
>> wrote:
>>
>> On 09/04/2018 10:14, Isuranga Perera wrote:
>>>
>>> The Read Committed isolation level ensures that data can only be read by
>>>> a
>>>> transaction if it is in the committed state. It doesn't completely
>>>> isolate
>>>> this transaction(create) hence some other transaction can still use this
>>>> method which results in the behavior I explained previously. Ideally If
>>>> we're gonna use @Transactional annotation the isolation level should be
>>>> serialized for create operation. Please correct me If I'm wrong.
>>>>
>>>> I see your point - while I don't completely agree about the likelihood
>>> of
>>> such race condition to actually happen.
>>>
>>> At worse, you might end up in having two distinct JWT (Access Tokens)
>>> values for a single user, which will anyway be subject to expiration due
>>> to
>>>
>>> https://github.com/apache/syncope/blob/master/core/provision
>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>> ng/java/job/ExpiredAccessTokenCleanup.java
>>>
>>> For additional security, we might want to impose a UNIQUE constraint on
>>>
>>> https://github.com/apache/syncope/blob/master/core/persisten
>>> ce-jpa/src/main/java/org/apache/syncope/core/persistenc
>>> e/jpa/entity/JPAAccessToken.java#L48
>>>
>>> (not sure to remember why the column is currently set as nullable,
>>> though).
>>> With UNIQUE owner, the step (5) in your sequence below will fail anyway.
>>>
>>> Again, given the chances that the race condition applies, and considering
>>> what would be the harm (nearly none, to me), I would rather avoid any
>>> modification rather than imposing the UNIQUE constraint.
>>>
>>>
>>> Regards.
>>>
>>> On Mon, Apr 9, 2018 at 1:12 PM, Francesco Chicchiriccò <
>>>
>>>> ilgrosso@apache.org>
>>>> wrote:
>>>>
>>>> On 09/04/2018 09:30, Isuranga Perera wrote:
>>>>
>>>>> Hi Francesco,
>>>>>
>>>>>> Yes there is @Transactional annotation. But it haven't set the
>>>>>> isolation
>>>>>> property as well as the propagation property. Based on the default
>>>>>> values
>>>>>> set this thread safe problem will still occur. Please correct me if
>>>>>> I'm
>>>>>> wrong.
>>>>>>
>>>>>> The transaction isolation level is set in
>>>>>>
>>>>> https://github.com/apache/syncope/blob/master/core/persisten
>>>>> ce-jpa/src/main/resources/domains/MasterDomain.xml#L57-L59
>>>>>
>>>>> Regards.
>>>>>
>>>>>
>>>>> On Mon, Apr 9, 2018 at 12:20 PM, Francesco Chicchiriccò <
>>>>>
>>>>> ilgrosso@apache.org> wrote:
>>>>>>
>>>>>> On 09/04/2018 08:46, Isuranga Perera wrote:
>>>>>>
>>>>>> Hi Francesco,
>>>>>>>
>>>>>>> I will take a scenario. Suppose a scenario where thread A & thread B
>>>>>>>> try
>>>>>>>> to login user admin.
>>>>>>>>
>>>>>>>> 1. thread A checks if a token exist for the user admin (suppose
>>>>>>>> currently there is no token associated with the admin)
>>>>>>>> 2. Then thread A execute following logic[1] to create and save
>>>>>>>> the
>>>>>>>> token.
>>>>>>>> 3. Before thread A save the token for user admin thread B checks
>>>>>>>> if a
>>>>>>>> token exist for user admin (since the toked created by
>>>>>>>> thread A
>>>>>>>> is
>>>>>>>> not yet saved *exist == null*)
>>>>>>>> 4. Then thread A complete the creation of token (and saving)
>>>>>>>> 5. Thread B also complete the creation and saving of the token.
>>>>>>>>
>>>>>>>> That way there can be 2 tokens for a particular user.
>>>>>>>>
>>>>>>>>
>>>>>>>> You analysis does not take into any account the fact of the
>>>>>>>> constraints
>>>>>>>>
>>>>>>>> imposed by the @Service annotation in
>>>>>>>
>>>>>>> https://github.com/apache/syncope/blob/master/core/rest-cxf/
>>>>>>> src/main/java/org/apache/syncope/core/rest/cxf/service/Acces
>>>>>>> sTokenServiceImpl.java#L35
>>>>>>>
>>>>>>> (e.g. the place when external requests can come in) nor by the
>>>>>>> @Transactional annotation injected into
>>>>>>>
>>>>>>> https://github.com/apache/syncope/blob/master/core/logic/
>>>>>>> src/main/java/org/apache/syncope/core/logic/AccessTokenLogic
>>>>>>> .java#L80
>>>>>>>
>>>>>>> via
>>>>>>>
>>>>>>> https://github.com/apache/syncope/blob/master/core/logic/
>>>>>>> src/main/java/org/apache/syncope/core/logic/AbstractTra
>>>>>>> nsactionalLogic.java#L29
>>>>>>>
>>>>>>> Regards.
>>>>>>>
>>>>>>> [1] https://github.com/apache/syncope/blob/master/core/provision
>>>>>>>
>>>>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>>
>>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L119
>>>>>>>>
>>>>>>>> Best Regards
>>>>>>>> Isuranga Perera
>>>>>>>>
>>>>>>>> On Mon, Apr 9, 2018 at 11:42 AM, Francesco Chicchiriccò <
>>>>>>>> ilgrosso@apache.org <ma...@apache.org>> wrote:
>>>>>>>>
>>>>>>>> On 09/04/2018 07:07, Isuranga Perera wrote:
>>>>>>>>
>>>>>>>> Hi All,
>>>>>>>>
>>>>>>>> Token create method in AccessTokenDataBinderImpl[1] is
>>>>>>>> not
>>>>>>>> thread safe.
>>>>>>>>
>>>>>>>>
>>>>>>>> Could you please explain why you're affirming this?
>>>>>>>>
>>>>>>>> This could result in several problems including
>>>>>>>>
>>>>>>>> * Exist 2 different access token for a particular user
>>>>>>>> at
>>>>>>>> a
>>>>>>>> given
>>>>>>>> time which may result in an exception thrown by
>>>>>>>> method
>>>>>>>> call[2]
>>>>>>>> since it expects a single token a given user.
>>>>>>>>
>>>>>>>> In addition to that token replace is implemented as a
>>>>>>>> combination of 2 different functionalities. Since the
>>>>>>>> method
>>>>>>>> is not thread safe this may cause some unexpected
>>>>>>>> behaviors
>>>>>>>> (since there can be 2 tokens exist for a particular user.
>>>>>>>> same
>>>>>>>> scenario as above).
>>>>>>>>
>>>>>>>> Appreciate your insight on the $subject.
>>>>>>>>
>>>>>>>>
>>>>>>>> [1]
>>>>>>>> https://github.com/apache/sync
>>>>>>>> ope/blob/master/core/provision
>>>>>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L104
>>>>>>>> <https://github.com/apache/syn
>>>>>>>> cope/blob/master/core/provisio
>>>>>>>> ning-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L104>
>>>>>>>>
>>>>>>>> [2]
>>>>>>>> https://github.com/apache/sync
>>>>>>>> ope/blob/master/core/provision
>>>>>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L113
>>>>>>>> <https://github.com/apache/syn
>>>>>>>> cope/blob/master/core/provisio
>>>>>>>> ning-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L113>
>>>>>>>>
>>>>>>>> Best Regards
>>>>>>>> Isuranga Perera
>>>>>>>>
>>>>>>>> --
> Francesco Chicchiriccò
>
> Tirasa - Open Source Excellence
> http://www.tirasa.net/
>
> Member at The Apache Software Foundation
> Syncope, Cocoon, Olingo, CXF, OpenJPA, PonyMail
> http://home.apache.org/~ilgrosso/
>
>
Re: Token creation is not thread safe
Posted by Francesco Chicchiriccò <il...@apache.org>.
On 09/04/2018 11:10, Isuranga Perera wrote:
> Since such condition can happen only if the same user tries to login from 2
> mediums at the same, this is rarely happen. However that slight chance may
> prevent that particular user from login to the system until all or all-1
> access tokens are expired.
> Using the UNIQUE constraint will definitely will provide a better security
> and furthermore will make the model more meaningful. On the other hand this
> will break the token replacing functionality since it first create a token
> (at this time there are 2 tokens in the db) and delete the last one.
>
> What I propose is writing a separate query to replace tokens instead of
> using save & delete queries separately and furthermore we can use a new
> query to save tokens without affecting the UNIQUE constraints so that no
> need to mess with threading & @Transactional properties.
If you can come up with a proposal which works with all the supported
DBMSes, then please go on.
As already asked as comment in your recent PR: did you submit an ICLA
for your contributions? Thanks.
Regards.
> On Mon, Apr 9, 2018 at 2:06 PM, Francesco Chicchiriccò <il...@apache.org>
> wrote:
>
>> On 09/04/2018 10:14, Isuranga Perera wrote:
>>
>>> The Read Committed isolation level ensures that data can only be read by a
>>> transaction if it is in the committed state. It doesn't completely isolate
>>> this transaction(create) hence some other transaction can still use this
>>> method which results in the behavior I explained previously. Ideally If
>>> we're gonna use @Transactional annotation the isolation level should be
>>> serialized for create operation. Please correct me If I'm wrong.
>>>
>> I see your point - while I don't completely agree about the likelihood of
>> such race condition to actually happen.
>>
>> At worse, you might end up in having two distinct JWT (Access Tokens)
>> values for a single user, which will anyway be subject to expiration due to
>>
>> https://github.com/apache/syncope/blob/master/core/provision
>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>> ng/java/job/ExpiredAccessTokenCleanup.java
>>
>> For additional security, we might want to impose a UNIQUE constraint on
>>
>> https://github.com/apache/syncope/blob/master/core/persisten
>> ce-jpa/src/main/java/org/apache/syncope/core/persistenc
>> e/jpa/entity/JPAAccessToken.java#L48
>>
>> (not sure to remember why the column is currently set as nullable, though).
>> With UNIQUE owner, the step (5) in your sequence below will fail anyway.
>>
>> Again, given the chances that the race condition applies, and considering
>> what would be the harm (nearly none, to me), I would rather avoid any
>> modification rather than imposing the UNIQUE constraint.
>>
>>
>> Regards.
>>
>> On Mon, Apr 9, 2018 at 1:12 PM, Francesco Chicchiriccò <
>>> ilgrosso@apache.org>
>>> wrote:
>>>
>>> On 09/04/2018 09:30, Isuranga Perera wrote:
>>>> Hi Francesco,
>>>>> Yes there is @Transactional annotation. But it haven't set the isolation
>>>>> property as well as the propagation property. Based on the default
>>>>> values
>>>>> set this thread safe problem will still occur. Please correct me if I'm
>>>>> wrong.
>>>>>
>>>>> The transaction isolation level is set in
>>>> https://github.com/apache/syncope/blob/master/core/persisten
>>>> ce-jpa/src/main/resources/domains/MasterDomain.xml#L57-L59
>>>>
>>>> Regards.
>>>>
>>>>
>>>> On Mon, Apr 9, 2018 at 12:20 PM, Francesco Chicchiriccò <
>>>>
>>>>> ilgrosso@apache.org> wrote:
>>>>>
>>>>> On 09/04/2018 08:46, Isuranga Perera wrote:
>>>>>
>>>>>> Hi Francesco,
>>>>>>
>>>>>>> I will take a scenario. Suppose a scenario where thread A & thread B
>>>>>>> try
>>>>>>> to login user admin.
>>>>>>>
>>>>>>> 1. thread A checks if a token exist for the user admin (suppose
>>>>>>> currently there is no token associated with the admin)
>>>>>>> 2. Then thread A execute following logic[1] to create and save the
>>>>>>> token.
>>>>>>> 3. Before thread A save the token for user admin thread B checks
>>>>>>> if a
>>>>>>> token exist for user admin (since the toked created by thread A
>>>>>>> is
>>>>>>> not yet saved *exist == null*)
>>>>>>> 4. Then thread A complete the creation of token (and saving)
>>>>>>> 5. Thread B also complete the creation and saving of the token.
>>>>>>>
>>>>>>> That way there can be 2 tokens for a particular user.
>>>>>>>
>>>>>>>
>>>>>>> You analysis does not take into any account the fact of the
>>>>>>> constraints
>>>>>>>
>>>>>> imposed by the @Service annotation in
>>>>>>
>>>>>> https://github.com/apache/syncope/blob/master/core/rest-cxf/
>>>>>> src/main/java/org/apache/syncope/core/rest/cxf/service/Acces
>>>>>> sTokenServiceImpl.java#L35
>>>>>>
>>>>>> (e.g. the place when external requests can come in) nor by the
>>>>>> @Transactional annotation injected into
>>>>>>
>>>>>> https://github.com/apache/syncope/blob/master/core/logic/
>>>>>> src/main/java/org/apache/syncope/core/logic/AccessTokenLogic.java#L80
>>>>>>
>>>>>> via
>>>>>>
>>>>>> https://github.com/apache/syncope/blob/master/core/logic/
>>>>>> src/main/java/org/apache/syncope/core/logic/AbstractTra
>>>>>> nsactionalLogic.java#L29
>>>>>>
>>>>>> Regards.
>>>>>>
>>>>>> [1] https://github.com/apache/syncope/blob/master/core/provision
>>>>>>
>>>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L119
>>>>>>>
>>>>>>> Best Regards
>>>>>>> Isuranga Perera
>>>>>>>
>>>>>>> On Mon, Apr 9, 2018 at 11:42 AM, Francesco Chicchiriccò <
>>>>>>> ilgrosso@apache.org <ma...@apache.org>> wrote:
>>>>>>>
>>>>>>> On 09/04/2018 07:07, Isuranga Perera wrote:
>>>>>>>
>>>>>>> Hi All,
>>>>>>>
>>>>>>> Token create method in AccessTokenDataBinderImpl[1] is not
>>>>>>> thread safe.
>>>>>>>
>>>>>>>
>>>>>>> Could you please explain why you're affirming this?
>>>>>>>
>>>>>>> This could result in several problems including
>>>>>>>
>>>>>>> * Exist 2 different access token for a particular user at
>>>>>>> a
>>>>>>> given
>>>>>>> time which may result in an exception thrown by method
>>>>>>> call[2]
>>>>>>> since it expects a single token a given user.
>>>>>>>
>>>>>>> In addition to that token replace is implemented as a
>>>>>>> combination of 2 different functionalities. Since the method
>>>>>>> is not thread safe this may cause some unexpected behaviors
>>>>>>> (since there can be 2 tokens exist for a particular user.
>>>>>>> same
>>>>>>> scenario as above).
>>>>>>>
>>>>>>> Appreciate your insight on the $subject.
>>>>>>>
>>>>>>>
>>>>>>> [1]
>>>>>>> https://github.com/apache/sync
>>>>>>> ope/blob/master/core/provision
>>>>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L104
>>>>>>> <https://github.com/apache/syn
>>>>>>> cope/blob/master/core/provisio
>>>>>>> ning-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L104>
>>>>>>>
>>>>>>> [2]
>>>>>>> https://github.com/apache/sync
>>>>>>> ope/blob/master/core/provision
>>>>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L113
>>>>>>> <https://github.com/apache/syn
>>>>>>> cope/blob/master/core/provisio
>>>>>>> ning-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L113>
>>>>>>>
>>>>>>> Best Regards
>>>>>>> Isuranga Perera
>>>>>>>
--
Francesco Chicchiriccò
Tirasa - Open Source Excellence
http://www.tirasa.net/
Member at The Apache Software Foundation
Syncope, Cocoon, Olingo, CXF, OpenJPA, PonyMail
http://home.apache.org/~ilgrosso/
Re: Token creation is not thread safe
Posted by Isuranga Perera <is...@gmail.com>.
Since such condition can happen only if the same user tries to login from 2
mediums at the same, this is rarely happen. However that slight chance may
prevent that particular user from login to the system until all or all-1
access tokens are expired.
Using the UNIQUE constraint will definitely will provide a better security
and furthermore will make the model more meaningful. On the other hand this
will break the token replacing functionality since it first create a token
(at this time there are 2 tokens in the db) and delete the last one.
What I propose is writing a separate query to replace tokens instead of
using save & delete queries separately and furthermore we can use a new
query to save tokens without affecting the UNIQUE constraints so that no
need to mess with threading & @Transactional properties.
On Mon, Apr 9, 2018 at 2:06 PM, Francesco Chicchiriccò <il...@apache.org>
wrote:
> On 09/04/2018 10:14, Isuranga Perera wrote:
>
>> The Read Committed isolation level ensures that data can only be read by a
>> transaction if it is in the committed state. It doesn't completely isolate
>> this transaction(create) hence some other transaction can still use this
>> method which results in the behavior I explained previously. Ideally If
>> we're gonna use @Transactional annotation the isolation level should be
>> serialized for create operation. Please correct me If I'm wrong.
>>
>
> I see your point - while I don't completely agree about the likelihood of
> such race condition to actually happen.
>
> At worse, you might end up in having two distinct JWT (Access Tokens)
> values for a single user, which will anyway be subject to expiration due to
>
> https://github.com/apache/syncope/blob/master/core/provision
> ing-java/src/main/java/org/apache/syncope/core/provisioni
> ng/java/job/ExpiredAccessTokenCleanup.java
>
> For additional security, we might want to impose a UNIQUE constraint on
>
> https://github.com/apache/syncope/blob/master/core/persisten
> ce-jpa/src/main/java/org/apache/syncope/core/persistenc
> e/jpa/entity/JPAAccessToken.java#L48
>
> (not sure to remember why the column is currently set as nullable, though).
> With UNIQUE owner, the step (5) in your sequence below will fail anyway.
>
> Again, given the chances that the race condition applies, and considering
> what would be the harm (nearly none, to me), I would rather avoid any
> modification rather than imposing the UNIQUE constraint.
>
>
> Regards.
>
> On Mon, Apr 9, 2018 at 1:12 PM, Francesco Chicchiriccò <
>> ilgrosso@apache.org>
>> wrote:
>>
>> On 09/04/2018 09:30, Isuranga Perera wrote:
>>>
>>> Hi Francesco,
>>>>
>>>> Yes there is @Transactional annotation. But it haven't set the isolation
>>>> property as well as the propagation property. Based on the default
>>>> values
>>>> set this thread safe problem will still occur. Please correct me if I'm
>>>> wrong.
>>>>
>>>> The transaction isolation level is set in
>>>
>>> https://github.com/apache/syncope/blob/master/core/persisten
>>> ce-jpa/src/main/resources/domains/MasterDomain.xml#L57-L59
>>>
>>> Regards.
>>>
>>>
>>> On Mon, Apr 9, 2018 at 12:20 PM, Francesco Chicchiriccò <
>>>
>>>> ilgrosso@apache.org> wrote:
>>>>
>>>> On 09/04/2018 08:46, Isuranga Perera wrote:
>>>>
>>>>> Hi Francesco,
>>>>>
>>>>>> I will take a scenario. Suppose a scenario where thread A & thread B
>>>>>> try
>>>>>> to login user admin.
>>>>>>
>>>>>> 1. thread A checks if a token exist for the user admin (suppose
>>>>>> currently there is no token associated with the admin)
>>>>>> 2. Then thread A execute following logic[1] to create and save the
>>>>>> token.
>>>>>> 3. Before thread A save the token for user admin thread B checks
>>>>>> if a
>>>>>> token exist for user admin (since the toked created by thread A
>>>>>> is
>>>>>> not yet saved *exist == null*)
>>>>>> 4. Then thread A complete the creation of token (and saving)
>>>>>> 5. Thread B also complete the creation and saving of the token.
>>>>>>
>>>>>> That way there can be 2 tokens for a particular user.
>>>>>>
>>>>>>
>>>>>> You analysis does not take into any account the fact of the
>>>>>> constraints
>>>>>>
>>>>> imposed by the @Service annotation in
>>>>>
>>>>> https://github.com/apache/syncope/blob/master/core/rest-cxf/
>>>>> src/main/java/org/apache/syncope/core/rest/cxf/service/Acces
>>>>> sTokenServiceImpl.java#L35
>>>>>
>>>>> (e.g. the place when external requests can come in) nor by the
>>>>> @Transactional annotation injected into
>>>>>
>>>>> https://github.com/apache/syncope/blob/master/core/logic/
>>>>> src/main/java/org/apache/syncope/core/logic/AccessTokenLogic.java#L80
>>>>>
>>>>> via
>>>>>
>>>>> https://github.com/apache/syncope/blob/master/core/logic/
>>>>> src/main/java/org/apache/syncope/core/logic/AbstractTra
>>>>> nsactionalLogic.java#L29
>>>>>
>>>>> Regards.
>>>>>
>>>>> [1] https://github.com/apache/syncope/blob/master/core/provision
>>>>>
>>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L119
>>>>>>
>>>>>> Best Regards
>>>>>> Isuranga Perera
>>>>>>
>>>>>> On Mon, Apr 9, 2018 at 11:42 AM, Francesco Chicchiriccò <
>>>>>> ilgrosso@apache.org <ma...@apache.org>> wrote:
>>>>>>
>>>>>> On 09/04/2018 07:07, Isuranga Perera wrote:
>>>>>>
>>>>>> Hi All,
>>>>>>
>>>>>> Token create method in AccessTokenDataBinderImpl[1] is not
>>>>>> thread safe.
>>>>>>
>>>>>>
>>>>>> Could you please explain why you're affirming this?
>>>>>>
>>>>>> This could result in several problems including
>>>>>>
>>>>>> * Exist 2 different access token for a particular user at
>>>>>> a
>>>>>> given
>>>>>> time which may result in an exception thrown by method
>>>>>> call[2]
>>>>>> since it expects a single token a given user.
>>>>>>
>>>>>> In addition to that token replace is implemented as a
>>>>>> combination of 2 different functionalities. Since the method
>>>>>> is not thread safe this may cause some unexpected behaviors
>>>>>> (since there can be 2 tokens exist for a particular user.
>>>>>> same
>>>>>> scenario as above).
>>>>>>
>>>>>> Appreciate your insight on the $subject.
>>>>>>
>>>>>>
>>>>>> [1]
>>>>>> https://github.com/apache/sync
>>>>>> ope/blob/master/core/provision
>>>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L104
>>>>>> <https://github.com/apache/syn
>>>>>> cope/blob/master/core/provisio
>>>>>> ning-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L104>
>>>>>>
>>>>>> [2]
>>>>>> https://github.com/apache/sync
>>>>>> ope/blob/master/core/provision
>>>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L113
>>>>>> <https://github.com/apache/syn
>>>>>> cope/blob/master/core/provisio
>>>>>> ning-java/src/main/java/org/apache/syncope/core/provisioni
>>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L113>
>>>>>>
>>>>>> Best Regards
>>>>>> Isuranga Perera
>>>>>>
>>>>>
>
> --
> Francesco Chicchiriccò
>
> Tirasa - Open Source Excellence
> http://www.tirasa.net/
>
> Member at The Apache Software Foundation
> Syncope, Cocoon, Olingo, CXF, OpenJPA, PonyMail
> http://home.apache.org/~ilgrosso/
>
>
Re: Token creation is not thread safe
Posted by Francesco Chicchiriccò <il...@apache.org>.
On 09/04/2018 10:14, Isuranga Perera wrote:
> The Read Committed isolation level ensures that data can only be read by a
> transaction if it is in the committed state. It doesn't completely isolate
> this transaction(create) hence some other transaction can still use this
> method which results in the behavior I explained previously. Ideally If
> we're gonna use @Transactional annotation the isolation level should be
> serialized for create operation. Please correct me If I'm wrong.
I see your point - while I don't completely agree about the likelihood
of such race condition to actually happen.
At worse, you might end up in having two distinct JWT (Access Tokens)
values for a single user, which will anyway be subject to expiration due to
https://github.com/apache/syncope/blob/master/core/provisioning-java/src/main/java/org/apache/syncope/core/provisioning/java/job/ExpiredAccessTokenCleanup.java
For additional security, we might want to impose a UNIQUE constraint on
https://github.com/apache/syncope/blob/master/core/persistence-jpa/src/main/java/org/apache/syncope/core/persistence/jpa/entity/JPAAccessToken.java#L48
(not sure to remember why the column is currently set as nullable, though).
With UNIQUE owner, the step (5) in your sequence below will fail anyway.
Again, given the chances that the race condition applies, and
considering what would be the harm (nearly none, to me), I would rather
avoid any modification rather than imposing the UNIQUE constraint.
Regards.
> On Mon, Apr 9, 2018 at 1:12 PM, Francesco Chicchiriccò <il...@apache.org>
> wrote:
>
>> On 09/04/2018 09:30, Isuranga Perera wrote:
>>
>>> Hi Francesco,
>>>
>>> Yes there is @Transactional annotation. But it haven't set the isolation
>>> property as well as the propagation property. Based on the default values
>>> set this thread safe problem will still occur. Please correct me if I'm
>>> wrong.
>>>
>> The transaction isolation level is set in
>>
>> https://github.com/apache/syncope/blob/master/core/persisten
>> ce-jpa/src/main/resources/domains/MasterDomain.xml#L57-L59
>>
>> Regards.
>>
>>
>> On Mon, Apr 9, 2018 at 12:20 PM, Francesco Chicchiriccò <
>>> ilgrosso@apache.org> wrote:
>>>
>>> On 09/04/2018 08:46, Isuranga Perera wrote:
>>>> Hi Francesco,
>>>>> I will take a scenario. Suppose a scenario where thread A & thread B try
>>>>> to login user admin.
>>>>>
>>>>> 1. thread A checks if a token exist for the user admin (suppose
>>>>> currently there is no token associated with the admin)
>>>>> 2. Then thread A execute following logic[1] to create and save the
>>>>> token.
>>>>> 3. Before thread A save the token for user admin thread B checks if a
>>>>> token exist for user admin (since the toked created by thread A is
>>>>> not yet saved *exist == null*)
>>>>> 4. Then thread A complete the creation of token (and saving)
>>>>> 5. Thread B also complete the creation and saving of the token.
>>>>>
>>>>> That way there can be 2 tokens for a particular user.
>>>>>
>>>>>
>>>>> You analysis does not take into any account the fact of the constraints
>>>> imposed by the @Service annotation in
>>>>
>>>> https://github.com/apache/syncope/blob/master/core/rest-cxf/
>>>> src/main/java/org/apache/syncope/core/rest/cxf/service/Acces
>>>> sTokenServiceImpl.java#L35
>>>>
>>>> (e.g. the place when external requests can come in) nor by the
>>>> @Transactional annotation injected into
>>>>
>>>> https://github.com/apache/syncope/blob/master/core/logic/
>>>> src/main/java/org/apache/syncope/core/logic/AccessTokenLogic.java#L80
>>>>
>>>> via
>>>>
>>>> https://github.com/apache/syncope/blob/master/core/logic/
>>>> src/main/java/org/apache/syncope/core/logic/AbstractTra
>>>> nsactionalLogic.java#L29
>>>>
>>>> Regards.
>>>>
>>>> [1] https://github.com/apache/syncope/blob/master/core/provision
>>>>
>>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L119
>>>>>
>>>>> Best Regards
>>>>> Isuranga Perera
>>>>>
>>>>> On Mon, Apr 9, 2018 at 11:42 AM, Francesco Chicchiriccò <
>>>>> ilgrosso@apache.org <ma...@apache.org>> wrote:
>>>>>
>>>>> On 09/04/2018 07:07, Isuranga Perera wrote:
>>>>>
>>>>> Hi All,
>>>>>
>>>>> Token create method in AccessTokenDataBinderImpl[1] is not
>>>>> thread safe.
>>>>>
>>>>>
>>>>> Could you please explain why you're affirming this?
>>>>>
>>>>> This could result in several problems including
>>>>>
>>>>> * Exist 2 different access token for a particular user at a
>>>>> given
>>>>> time which may result in an exception thrown by method
>>>>> call[2]
>>>>> since it expects a single token a given user.
>>>>>
>>>>> In addition to that token replace is implemented as a
>>>>> combination of 2 different functionalities. Since the method
>>>>> is not thread safe this may cause some unexpected behaviors
>>>>> (since there can be 2 tokens exist for a particular user. same
>>>>> scenario as above).
>>>>>
>>>>> Appreciate your insight on the $subject.
>>>>>
>>>>>
>>>>> [1]
>>>>> https://github.com/apache/syncope/blob/master/core/provision
>>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L104
>>>>> <https://github.com/apache/syncope/blob/master/core/provisio
>>>>> ning-java/src/main/java/org/apache/syncope/core/provisioni
>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L104>
>>>>>
>>>>> [2]
>>>>> https://github.com/apache/syncope/blob/master/core/provision
>>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L113
>>>>> <https://github.com/apache/syncope/blob/master/core/provisio
>>>>> ning-java/src/main/java/org/apache/syncope/core/provisioni
>>>>> ng/java/data/AccessTokenDataBinderImpl.java#L113>
>>>>>
>>>>> Best Regards
>>>>> Isuranga Perera
--
Francesco Chicchiriccò
Tirasa - Open Source Excellence
http://www.tirasa.net/
Member at The Apache Software Foundation
Syncope, Cocoon, Olingo, CXF, OpenJPA, PonyMail
http://home.apache.org/~ilgrosso/
Re: Token creation is not thread safe
Posted by Isuranga Perera <is...@gmail.com>.
The Read Committed isolation level ensures that data can only be read by a
transaction if it is in the committed state. It doesn't completely isolate
this transaction(create) hence some other transaction can still use this
method which results in the behavior I explained previously. Ideally If
we're gonna use @Transactional annotation the isolation level should be
serialized for create operation. Please correct me If I'm wrong.
On Mon, Apr 9, 2018 at 1:12 PM, Francesco Chicchiriccò <il...@apache.org>
wrote:
> On 09/04/2018 09:30, Isuranga Perera wrote:
>
>> Hi Francesco,
>>
>> Yes there is @Transactional annotation. But it haven't set the isolation
>> property as well as the propagation property. Based on the default values
>> set this thread safe problem will still occur. Please correct me if I'm
>> wrong.
>>
>
> The transaction isolation level is set in
>
> https://github.com/apache/syncope/blob/master/core/persisten
> ce-jpa/src/main/resources/domains/MasterDomain.xml#L57-L59
>
> Regards.
>
>
> On Mon, Apr 9, 2018 at 12:20 PM, Francesco Chicchiriccò <
>> ilgrosso@apache.org> wrote:
>>
>> On 09/04/2018 08:46, Isuranga Perera wrote:
>>>
>>> Hi Francesco,
>>>>
>>>> I will take a scenario. Suppose a scenario where thread A & thread B try
>>>> to login user admin.
>>>>
>>>> 1. thread A checks if a token exist for the user admin (suppose
>>>> currently there is no token associated with the admin)
>>>> 2. Then thread A execute following logic[1] to create and save the
>>>> token.
>>>> 3. Before thread A save the token for user admin thread B checks if a
>>>> token exist for user admin (since the toked created by thread A is
>>>> not yet saved *exist == null*)
>>>> 4. Then thread A complete the creation of token (and saving)
>>>> 5. Thread B also complete the creation and saving of the token.
>>>>
>>>> That way there can be 2 tokens for a particular user.
>>>>
>>>>
>>>> You analysis does not take into any account the fact of the constraints
>>> imposed by the @Service annotation in
>>>
>>> https://github.com/apache/syncope/blob/master/core/rest-cxf/
>>> src/main/java/org/apache/syncope/core/rest/cxf/service/Acces
>>> sTokenServiceImpl.java#L35
>>>
>>> (e.g. the place when external requests can come in) nor by the
>>> @Transactional annotation injected into
>>>
>>> https://github.com/apache/syncope/blob/master/core/logic/
>>> src/main/java/org/apache/syncope/core/logic/AccessTokenLogic.java#L80
>>>
>>> via
>>>
>>> https://github.com/apache/syncope/blob/master/core/logic/
>>> src/main/java/org/apache/syncope/core/logic/AbstractTra
>>> nsactionalLogic.java#L29
>>>
>>> Regards.
>>>
>>> [1] https://github.com/apache/syncope/blob/master/core/provision
>>>
>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>> ng/java/data/AccessTokenDataBinderImpl.java#L119
>>>>
>>>> Best Regards
>>>> Isuranga Perera
>>>>
>>>> On Mon, Apr 9, 2018 at 11:42 AM, Francesco Chicchiriccò <
>>>> ilgrosso@apache.org <ma...@apache.org>> wrote:
>>>>
>>>> On 09/04/2018 07:07, Isuranga Perera wrote:
>>>>
>>>> Hi All,
>>>>
>>>> Token create method in AccessTokenDataBinderImpl[1] is not
>>>> thread safe.
>>>>
>>>>
>>>> Could you please explain why you're affirming this?
>>>>
>>>> This could result in several problems including
>>>>
>>>> * Exist 2 different access token for a particular user at a
>>>> given
>>>> time which may result in an exception thrown by method
>>>> call[2]
>>>> since it expects a single token a given user.
>>>>
>>>> In addition to that token replace is implemented as a
>>>> combination of 2 different functionalities. Since the method
>>>> is not thread safe this may cause some unexpected behaviors
>>>> (since there can be 2 tokens exist for a particular user. same
>>>> scenario as above).
>>>>
>>>> Appreciate your insight on the $subject.
>>>>
>>>>
>>>> [1]
>>>> https://github.com/apache/syncope/blob/master/core/provision
>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>> ng/java/data/AccessTokenDataBinderImpl.java#L104
>>>> <https://github.com/apache/syncope/blob/master/core/provisio
>>>> ning-java/src/main/java/org/apache/syncope/core/provisioni
>>>> ng/java/data/AccessTokenDataBinderImpl.java#L104>
>>>>
>>>> [2]
>>>> https://github.com/apache/syncope/blob/master/core/provision
>>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>>> ng/java/data/AccessTokenDataBinderImpl.java#L113
>>>> <https://github.com/apache/syncope/blob/master/core/provisio
>>>> ning-java/src/main/java/org/apache/syncope/core/provisioni
>>>> ng/java/data/AccessTokenDataBinderImpl.java#L113>
>>>>
>>>> Best Regards
>>>> Isuranga Perera
>>>>
>>>
> --
> Francesco Chicchiriccò
>
> Tirasa - Open Source Excellence
> http://www.tirasa.net/
>
> Member at The Apache Software Foundation
> Syncope, Cocoon, Olingo, CXF, OpenJPA, PonyMail
> http://home.apache.org/~ilgrosso/
>
>
Re: Token creation is not thread safe
Posted by Francesco Chicchiriccò <il...@apache.org>.
On 09/04/2018 09:30, Isuranga Perera wrote:
> Hi Francesco,
>
> Yes there is @Transactional annotation. But it haven't set the isolation
> property as well as the propagation property. Based on the default values
> set this thread safe problem will still occur. Please correct me if I'm
> wrong.
The transaction isolation level is set in
https://github.com/apache/syncope/blob/master/core/persistence-jpa/src/main/resources/domains/MasterDomain.xml#L57-L59
Regards.
> On Mon, Apr 9, 2018 at 12:20 PM, Francesco Chicchiriccò <il...@apache.org> wrote:
>
>> On 09/04/2018 08:46, Isuranga Perera wrote:
>>
>>> Hi Francesco,
>>>
>>> I will take a scenario. Suppose a scenario where thread A & thread B try
>>> to login user admin.
>>>
>>> 1. thread A checks if a token exist for the user admin (suppose
>>> currently there is no token associated with the admin)
>>> 2. Then thread A execute following logic[1] to create and save the token.
>>> 3. Before thread A save the token for user admin thread B checks if a
>>> token exist for user admin (since the toked created by thread A is
>>> not yet saved *exist == null*)
>>> 4. Then thread A complete the creation of token (and saving)
>>> 5. Thread B also complete the creation and saving of the token.
>>>
>>> That way there can be 2 tokens for a particular user.
>>>
>>>
>> You analysis does not take into any account the fact of the constraints
>> imposed by the @Service annotation in
>>
>> https://github.com/apache/syncope/blob/master/core/rest-cxf/
>> src/main/java/org/apache/syncope/core/rest/cxf/service/Acces
>> sTokenServiceImpl.java#L35
>>
>> (e.g. the place when external requests can come in) nor by the
>> @Transactional annotation injected into
>>
>> https://github.com/apache/syncope/blob/master/core/logic/
>> src/main/java/org/apache/syncope/core/logic/AccessTokenLogic.java#L80
>>
>> via
>>
>> https://github.com/apache/syncope/blob/master/core/logic/
>> src/main/java/org/apache/syncope/core/logic/AbstractTra
>> nsactionalLogic.java#L29
>>
>> Regards.
>>
>> [1] https://github.com/apache/syncope/blob/master/core/provision
>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>> ng/java/data/AccessTokenDataBinderImpl.java#L119
>>>
>>> Best Regards
>>> Isuranga Perera
>>>
>>> On Mon, Apr 9, 2018 at 11:42 AM, Francesco Chicchiriccò <
>>> ilgrosso@apache.org <ma...@apache.org>> wrote:
>>>
>>> On 09/04/2018 07:07, Isuranga Perera wrote:
>>>
>>> Hi All,
>>>
>>> Token create method in AccessTokenDataBinderImpl[1] is not
>>> thread safe.
>>>
>>>
>>> Could you please explain why you're affirming this?
>>>
>>> This could result in several problems including
>>>
>>> * Exist 2 different access token for a particular user at a
>>> given
>>> time which may result in an exception thrown by method call[2]
>>> since it expects a single token a given user.
>>>
>>> In addition to that token replace is implemented as a
>>> combination of 2 different functionalities. Since the method
>>> is not thread safe this may cause some unexpected behaviors
>>> (since there can be 2 tokens exist for a particular user. same
>>> scenario as above).
>>>
>>> Appreciate your insight on the $subject.
>>>
>>>
>>> [1]
>>> https://github.com/apache/syncope/blob/master/core/provision
>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>> ng/java/data/AccessTokenDataBinderImpl.java#L104
>>> <https://github.com/apache/syncope/blob/master/core/provisio
>>> ning-java/src/main/java/org/apache/syncope/core/provisioni
>>> ng/java/data/AccessTokenDataBinderImpl.java#L104>
>>>
>>> [2]
>>> https://github.com/apache/syncope/blob/master/core/provision
>>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>>> ng/java/data/AccessTokenDataBinderImpl.java#L113
>>> <https://github.com/apache/syncope/blob/master/core/provisio
>>> ning-java/src/main/java/org/apache/syncope/core/provisioni
>>> ng/java/data/AccessTokenDataBinderImpl.java#L113>
>>>
>>> Best Regards
>>> Isuranga Perera
--
Francesco Chicchiriccò
Tirasa - Open Source Excellence
http://www.tirasa.net/
Member at The Apache Software Foundation
Syncope, Cocoon, Olingo, CXF, OpenJPA, PonyMail
http://home.apache.org/~ilgrosso/
Re: Token creation is not thread safe
Posted by Isuranga Perera <is...@gmail.com>.
Hi Francesco,
Yes there is @Transactional annotation. But it haven't set the isolation
property as well as the propagation property. Based on the default values
set this thread safe problem will still occur. Please correct me if I'm
wrong.
Best Regards
On Mon, Apr 9, 2018 at 12:20 PM, Francesco Chicchiriccò <ilgrosso@apache.org
> wrote:
> On 09/04/2018 08:46, Isuranga Perera wrote:
>
>> Hi Francesco,
>>
>> I will take a scenario. Suppose a scenario where thread A & thread B try
>> to login user admin.
>>
>> 1. thread A checks if a token exist for the user admin (suppose
>> currently there is no token associated with the admin)
>> 2. Then thread A execute following logic[1] to create and save the token.
>> 3. Before thread A save the token for user admin thread B checks if a
>> token exist for user admin (since the toked created by thread A is
>> not yet saved *exist == null*)
>> 4. Then thread A complete the creation of token (and saving)
>> 5. Thread B also complete the creation and saving of the token.
>>
>> That way there can be 2 tokens for a particular user.
>>
>>
> You analysis does not take into any account the fact of the constraints
> imposed by the @Service annotation in
>
> https://github.com/apache/syncope/blob/master/core/rest-cxf/
> src/main/java/org/apache/syncope/core/rest/cxf/service/Acces
> sTokenServiceImpl.java#L35
>
> (e.g. the place when external requests can come in) nor by the
> @Transactional annotation injected into
>
> https://github.com/apache/syncope/blob/master/core/logic/
> src/main/java/org/apache/syncope/core/logic/AccessTokenLogic.java#L80
>
> via
>
> https://github.com/apache/syncope/blob/master/core/logic/
> src/main/java/org/apache/syncope/core/logic/AbstractTra
> nsactionalLogic.java#L29
>
> Regards.
>
> [1] https://github.com/apache/syncope/blob/master/core/provision
>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>> ng/java/data/AccessTokenDataBinderImpl.java#L119
>>
>> Best Regards
>> Isuranga Perera
>>
>> On Mon, Apr 9, 2018 at 11:42 AM, Francesco Chicchiriccò <
>> ilgrosso@apache.org <ma...@apache.org>> wrote:
>>
>> On 09/04/2018 07:07, Isuranga Perera wrote:
>>
>> Hi All,
>>
>> Token create method in AccessTokenDataBinderImpl[1] is not
>> thread safe.
>>
>>
>> Could you please explain why you're affirming this?
>>
>> This could result in several problems including
>>
>> * Exist 2 different access token for a particular user at a
>> given
>> time which may result in an exception thrown by method call[2]
>> since it expects a single token a given user.
>>
>> In addition to that token replace is implemented as a
>> combination of 2 different functionalities. Since the method
>> is not thread safe this may cause some unexpected behaviors
>> (since there can be 2 tokens exist for a particular user. same
>> scenario as above).
>>
>> Appreciate your insight on the $subject.
>>
>>
>> [1]
>> https://github.com/apache/syncope/blob/master/core/provision
>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>> ng/java/data/AccessTokenDataBinderImpl.java#L104
>> <https://github.com/apache/syncope/blob/master/core/provisio
>> ning-java/src/main/java/org/apache/syncope/core/provisioni
>> ng/java/data/AccessTokenDataBinderImpl.java#L104>
>>
>> [2]
>> https://github.com/apache/syncope/blob/master/core/provision
>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>> ng/java/data/AccessTokenDataBinderImpl.java#L113
>> <https://github.com/apache/syncope/blob/master/core/provisio
>> ning-java/src/main/java/org/apache/syncope/core/provisioni
>> ng/java/data/AccessTokenDataBinderImpl.java#L113>
>>
>> Best Regards
>> Isuranga Perera
>>
>> --
> Francesco Chicchiriccò
>
> Tirasa - Open Source Excellence
> http://www.tirasa.net/
>
> Member at The Apache Software Foundation
> Syncope, Cocoon, Olingo, CXF, OpenJPA, PonyMail
> http://home.apache.org/~ilgrosso/
>
>
Re: Token creation is not thread safe
Posted by Francesco Chicchiriccò <il...@apache.org>.
On 09/04/2018 08:46, Isuranga Perera wrote:
> Hi Francesco,
>
> I will take a scenario. Suppose a scenario where thread A & thread B
> try to login user admin.
>
> 1. thread A checks if a token exist for the user admin (suppose
> currently there is no token associated with the admin)
> 2. Then thread A execute following logic[1] to create and save the token.
> 3. Before thread A save the token for user admin thread B checks if a
> token exist for user admin (since the toked created by thread A is
> not yet saved *exist == null*)
> 4. Then thread A complete the creation of token (and saving)
> 5. Thread B also complete the creation and saving of the token.
>
> That way there can be 2 tokens for a particular user.
>
You analysis does not take into any account the fact of the constraints
imposed by the @Service annotation in
https://github.com/apache/syncope/blob/master/core/rest-cxf/src/main/java/org/apache/syncope/core/rest/cxf/service/AccessTokenServiceImpl.java#L35
(e.g. the place when external requests can come in) nor by the
@Transactional annotation injected into
https://github.com/apache/syncope/blob/master/core/logic/src/main/java/org/apache/syncope/core/logic/AccessTokenLogic.java#L80
via
https://github.com/apache/syncope/blob/master/core/logic/src/main/java/org/apache/syncope/core/logic/AbstractTransactionalLogic.java#L29
Regards.
> [1]
> https://github.com/apache/syncope/blob/master/core/provisioning-java/src/main/java/org/apache/syncope/core/provisioning/java/data/AccessTokenDataBinderImpl.java#L119
>
> Best Regards
> Isuranga Perera
>
> On Mon, Apr 9, 2018 at 11:42 AM, Francesco Chicchiriccò
> <ilgrosso@apache.org <ma...@apache.org>> wrote:
>
> On 09/04/2018 07:07, Isuranga Perera wrote:
>
> Hi All,
>
> Token create method in AccessTokenDataBinderImpl[1] is not
> thread safe.
>
>
> Could you please explain why you're affirming this?
>
> This could result in several problems including
>
> * Exist 2 different access token for a particular user at a
> given
> time which may result in an exception thrown by method call[2]
> since it expects a single token a given user.
>
> In addition to that token replace is implemented as a
> combination of 2 different functionalities. Since the method
> is not thread safe this may cause some unexpected behaviors
> (since there can be 2 tokens exist for a particular user. same
> scenario as above).
>
> Appreciate your insight on the $subject.
>
>
> [1]
> https://github.com/apache/syncope/blob/master/core/provisioning-java/src/main/java/org/apache/syncope/core/provisioning/java/data/AccessTokenDataBinderImpl.java#L104
> <https://github.com/apache/syncope/blob/master/core/provisioning-java/src/main/java/org/apache/syncope/core/provisioning/java/data/AccessTokenDataBinderImpl.java#L104>
>
> [2]
> https://github.com/apache/syncope/blob/master/core/provisioning-java/src/main/java/org/apache/syncope/core/provisioning/java/data/AccessTokenDataBinderImpl.java#L113
> <https://github.com/apache/syncope/blob/master/core/provisioning-java/src/main/java/org/apache/syncope/core/provisioning/java/data/AccessTokenDataBinderImpl.java#L113>
>
> Best Regards
> Isuranga Perera
>
--
Francesco Chicchiriccò
Tirasa - Open Source Excellence
http://www.tirasa.net/
Member at The Apache Software Foundation
Syncope, Cocoon, Olingo, CXF, OpenJPA, PonyMail
http://home.apache.org/~ilgrosso/
Re: Token creation is not thread safe
Posted by Isuranga Perera <is...@gmail.com>.
Hi Francesco,
I will take a scenario. Suppose a scenario where thread A & thread B try to
login user admin.
1. thread A checks if a token exist for the user admin (suppose
currently there is no token associated with the admin)
2. Then thread A execute following logic[1] to create and save the token.
3. Before thread A save the token for user admin thread B checks if a
token exist for user admin (since the toked created by thread A is not yet
saved *exist == null*)
4. Then thread A complete the creation of token (and saving)
5. Thread B also complete the creation and saving of the token.
That way there can be 2 tokens for a particular user.
[1]
https://github.com/apache/syncope/blob/master/core/provisioning-java/src/main/java/org/apache/syncope/core/provisioning/java/data/AccessTokenDataBinderImpl.java#L119
Best Regards
Isuranga Perera
On Mon, Apr 9, 2018 at 11:42 AM, Francesco Chicchiriccò <ilgrosso@apache.org
> wrote:
> On 09/04/2018 07:07, Isuranga Perera wrote:
>
>> Hi All,
>>
>> Token create method in AccessTokenDataBinderImpl[1] is not thread safe.
>>
>
> Could you please explain why you're affirming this?
>
> This could result in several problems including
>>
>> * Exist 2 different access token for a particular user at a given
>> time which may result in an exception thrown by method call[2]
>> since it expects a single token a given user.
>>
>> In addition to that token replace is implemented as a combination of 2
>> different functionalities. Since the method is not thread safe this may
>> cause some unexpected behaviors (since there can be 2 tokens exist for a
>> particular user. same scenario as above).
>>
>> Appreciate your insight on the $subject.
>>
>>
>> [1] https://github.com/apache/syncope/blob/master/core/provision
>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>> ng/java/data/AccessTokenDataBinderImpl.java#L104
>>
>> [2] https://github.com/apache/syncope/blob/master/core/provision
>> ing-java/src/main/java/org/apache/syncope/core/provisioni
>> ng/java/data/AccessTokenDataBinderImpl.java#L113
>>
>> Best Regards
>> Isuranga Perera
>>
>
>
> --
> Francesco Chicchiriccò
>
> Tirasa - Open Source Excellence
> http://www.tirasa.net/
>
> Member at The Apache Software Foundation
> Syncope, Cocoon, Olingo, CXF, OpenJPA, PonyMail
> http://home.apache.org/~ilgrosso/
>
>
Re: Token creation is not thread safe
Posted by Francesco Chicchiriccò <il...@apache.org>.
On 09/04/2018 07:07, Isuranga Perera wrote:
> Hi All,
>
> Token create method in AccessTokenDataBinderImpl[1] is not thread safe.
Could you please explain why you're affirming this?
> This could result in several problems including
>
> * Exist 2 different access token for a particular user at a given
> time which may result in an exception thrown by method call[2]
> since it expects a single token a given user.
>
> In addition to that token replace is implemented as a combination of 2
> different functionalities. Since the method is not thread safe this
> may cause some unexpected behaviors (since there can be 2 tokens exist
> for a particular user. same scenario as above).
>
> Appreciate your insight on the $subject.
>
>
> [1]
> https://github.com/apache/syncope/blob/master/core/provisioning-java/src/main/java/org/apache/syncope/core/provisioning/java/data/AccessTokenDataBinderImpl.java#L104
>
> [2]
> https://github.com/apache/syncope/blob/master/core/provisioning-java/src/main/java/org/apache/syncope/core/provisioning/java/data/AccessTokenDataBinderImpl.java#L113
>
> Best Regards
> Isuranga Perera
--
Francesco Chicchiriccò
Tirasa - Open Source Excellence
http://www.tirasa.net/
Member at The Apache Software Foundation
Syncope, Cocoon, Olingo, CXF, OpenJPA, PonyMail
http://home.apache.org/~ilgrosso/