From: Pavel Machek <pavel-+ZI9xUNit7I@public.gmane.org>
Subject: Re: [PATCH 17/18] Hibernate: introduced SNAPSHOT_SIG_HASH config
 for select hash algorithm
Date: Sun, 25 Aug 2013 18:43:29 +0200
Message-ID: <20130825164329.GL5171@amd.pavel.ucw.cz>
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	"Lee, Chun-Yi" <jlee-IBi9RG/b67k@public.gmane.org>
To: "Lee, Chun-Yi" <joeyli.kernel-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
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On Thu 2013-08-22 19:01:56, Lee, Chun-Yi wrote:
> This patch introduced SNAPSHOT_SIG_HASH config for user to select which
> hash algorithm will be used during signature generation of snapshot.
> 
> v2:
> Add define check of oCONFIG_SNAPSHOT_VERIFICATION in snapshot.c before
> declare pkey_hash().
> 
> Reviewed-by: Jiri Kosina <jkosina-AlSwsSmVLrQ@public.gmane.org>
> Signed-off-by: Lee, Chun-Yi <jlee-IBi9RG/b67k@public.gmane.org>
> ---
>  kernel/power/Kconfig    |   46 ++++++++++++++++++++++++++++++++++++++++++++++
>  kernel/power/snapshot.c |   27 ++++++++++++++++++++++-----
>  2 files changed, 68 insertions(+), 5 deletions(-)
> 
> diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig
> index b592d88..79b34fa 100644
> --- a/kernel/power/Kconfig
> +++ b/kernel/power/Kconfig
> @@ -78,6 +78,52 @@ config SNAPSHOT_VERIFICATION
>  	  dependent on UEFI environment. EFI bootloader should generate the
>  	  key-pair.
>  
> +choice
> +	prompt "Which hash algorithm should snapshot be signed with?"
> +        depends on SNAPSHOT_VERIFICATION
> +        help
> +          This determines which sort of hashing algorithm will be used during
> +          signature generation of snapshot. This algorithm _must_ be built into
> +	  the kernel directly so that signature verification can take place.
> +	  It is not possible to load a signed snapshot containing the algorithm
> +	  to check the signature on that module.

Like if 1000 ifdefs you already added to the code are not enough, you
make some new ones?
									Pavel

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