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On 09/28/2014 09:23 PM, Steven J. Long wrote: |
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> On Wed, Sep 24, 2014 at 09:51:31PM -0700, Zac Medico wrote: |
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>> On 07/09/2014 07:17 AM, Michał Górny wrote: |
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>>>>> c) 'esudo' helper [3]. This is a more generic form of (2), with |
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>>>>> support for other potential privilege changes. |
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>>>> |
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> .. |
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>>> I don't think we'd use the reference 'sudo' impl. Rather some |
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>>> in-portage helper, possibly setuid. Or portage's IPC but that would |
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>>> imply running the command in an isolated environment (possibly |
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>>> beneficial). |
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>> |
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>> The environment doesn't necessarily have to be isolated, since we could |
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>> extend the existing environment saving/loading support to be used for by |
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>> esudo. The steps to implement the shared environment could be as follows: |
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>> |
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>> 1) When esudo is called, it saves the current (unprivileged) bash |
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>> environment to a file. |
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>> |
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>> 2) esudo uses IPC to request that a process with elevated privileges be |
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>> launched to run a specific command using the saved environment, and that |
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>> the environment of the elevated process be saved to a file after the |
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>> command completes. |
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> |
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> I don't think it's going to be quite that easy to get the output env, |
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> certainly not from some random command; tbh I don't even see the need |
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> for it, unless I'm missing something. From the "elevated process" after |
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> it waits on the child, but not from the child unless you control the |
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> code. |
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|
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We control the shell code that launches the requested command, so we can |
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save the environment after the requested command completes (using a |
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modified version of our existing environment persistence code). |
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>> 3) Before esudo returns, it loads the environment that was saved by the |
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>> elevated process before it exited. |
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> |
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> What's the use-case for this part? I could see it with a function, but |
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> then you just run that as part of the ebuild. For running a specific |
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> command to access a device with privilege, or to add a user etc, I |
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> don't really see the point. (so why bother with the implementation |
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> complexity.) |
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Well, maybe it's not very useful. I just thought I'd mention it in case |
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anyone found it useful for some reason. |
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> Other than that, I agree esudo is the best approach, and gives us |
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> much better granularity over privilege escalation, as discussed in |
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> the bug. |
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Yeah, me too. |
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> Part of me thinks though, that it'd be much cleaner to give the |
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> portage user access to sudo. Isn't that effectively the purpose |
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> of the "suid helper"? In which case we get all the options for |
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> env etc, of sudo, and the admin gets to configure it along with |
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> the normal wheel setup. |
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Depending on our goals, using sudo may or may not have advantages. It. |
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really depends on whether or not we want esudo to interact with the |
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local sudo configuration. If we want it to be independent of the local |
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sudo configuration, then it makes sense for the package manager to use |
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it's own privilege escalation mechanism. |
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-- |
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Thanks, |
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Zac |
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