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Date:   Tue, 9 Jul 2019 22:38:32 +0800
From:   Herbert Xu <herbert@gondor.apana.org.au>
To:     Ondrej Mosnacek <omosnace@redhat.com>
Cc:     linux-crypto@vger.kernel.org, netdev@vger.kernel.org,
        "David S . Miller" <davem@davemloft.net>,
        Stephan Mueller <smueller@chronox.de>,
        Steffen Klassert <steffen.klassert@secunet.com>,
        Don Zickus <dzickus@redhat.com>
Subject: Re: [PATCH] crypto: user - make NETLINK_CRYPTO work inside netns
Message-ID: <20190709143832.hej23rahmb4basy6@gondor.apana.org.au>
References: <20190709111124.31127-1-omosnace@redhat.com>
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On Tue, Jul 09, 2019 at 01:11:24PM +0200, Ondrej Mosnacek wrote:
> Currently, NETLINK_CRYPTO works only in the init network namespace. It
> doesn't make much sense to cut it out of the other network namespaces,
> so do the minor plumbing work necessary to make it work in any network
> namespace. Code inspired by net/core/sock_diag.c.
> 
> Tested using kcapi-dgst from libkcapi [1]:
> Before:
>     # unshare -n kcapi-dgst -c sha256 </dev/null | wc -c
>     libkcapi - Error: Netlink error: sendmsg failed
>     libkcapi - Error: Netlink error: sendmsg failed
>     libkcapi - Error: NETLINK_CRYPTO: cannot obtain cipher information for hmac(sha512) (is required crypto_user.c patch missing? see documentation)
>     0
> 
> After:
>     # unshare -n kcapi-dgst -c sha256 </dev/null | wc -c
>     32
> 
> [1] https://github.com/smuellerDD/libkcapi
> 
> Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>

Should we really let root inside a namespace manipulate crypto
algorithms which are global?

I think we should only allow the query operations without deeper
surgery.

Cheers,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt