netdev - Re: [PATCH 1/1] [DCCP][QPOLICY]: Make information about qpolicies available to userspace

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Sun, 8 Jun 2008 14:21:25 +0200
From:	Tomasz Grobelny <tomasz@...belny.oswiecenia.net>
To:	Gerrit Renker <gerrit@....abdn.ac.uk>
Cc:	acme@...hat.com, dccp@...r.kernel.org, netdev@...r.kernel.org
Subject: Re: [PATCH 1/1] [DCCP][QPOLICY]: Make information about qpolicies available to userspace

Dnia Wednesday 04 of June 2008, Gerrit Renker napisał:
> | Now that I had a closer look at implementing this functionality I have a
> | few questions:
> | 1. Where should information about available qpolicies and their parametrs
> | be exported? Would /proc/net/dccp/qpolicies/ be a good choice?
>
> For a sketch or a first implementation, procfs sounds like a good starting
> point.
>
> But since it is about dynamic runtime configuration, how about using sysfs
> or configfs instead? This is a brainstorming question, I think that sysfs
> is generally preferred. I don't know how well configfs has taken off, it is
> similar, but needs to be added in the configuration (under Pseudeo
> Filesystems, CONFIG_CONFIGFS_FS=y|m) http://lwn.net/Articles/148973/
> and Documentation/filesystems/configs. But this could be done later as
> well.
>
procfs has some fine example of being used for this kind of information, 
namely /proc/cpuinfo and /proc/meminfo
sysfs: from sysfs-rules.txt: "(...) the sysfs interface cannot provide a 
stable interface (...)"
configfs is for configuring kernel from userspace. Which is quite opposite to  
what we want.

> | 2. I guess we should have at least one file per qpolicy with parameters
> | listed inside. Like that:
> | /proc/.../qpolicies/simple: <empty>
> | /proc/.../qpolicies/prio: 1 (DCCP_SCM_PRIORITY) 2 (DCCP_SCM_TIMEOUT)
>
> Hm this is a "policy" question -- isn't the `timeout' policy a
> standalone variant?
>
It seems we have a bit different views on the subject. But that's to be 
decided when somebody comes round to implementing timeout.

> | But we could also have qpolicy represented by directory and parameters by
> | files: /proc/.../qpolicies/simple/
> | /proc/.../qpolicies/prio/
> | /proc/.../qpolicies/prio/priority: <empty>
> | /proc/.../qpolicies/prio/timeout: <empty>
> | Which layout do you find better?
> | --
>
> I don't like the empty files. In the procfs for thinkpad Acpi
> configuration, for example, there is a line that says which commands are
> acceptable, similar for /sys/power/state. In that way, the (sysfs|procfs)
> file documents itself and tells the user what can be done with it. It would
> be great if the qpolicies could do something similar.
>
Ok, I'll try to write a simple patch for that.
-- 
Regards,
Tomasz Grobelny
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html