linux-kernel - Re: [PATCH v2] crypto: AF_ALG - add support for keys/asymmetric-type

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: Windows password security audit tool. GUI, reports in PDF.

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

Date:	Wed, 13 Jan 2016 06:05:32 -0800
From:	Tadeusz Struk <tadeusz.struk@...el.com>
To:	David Howells <dhowells@...hat.com>,
	Tadeusz Struk <tstruk@...il.com>
Cc:	herbert@...dor.apana.org.au, smueller@...onox.de,
	linux-api@...r.kernel.org, marcel@...tmann.org,
	linux-kernel@...r.kernel.org, keyrings@...r.kernel.org,
	linux-crypto@...r.kernel.org, zohar@...ux.vnet.ibm.com,
	dwmw2@...radead.org
Subject: Re: [PATCH v2] crypto: AF_ALG - add support for keys/asymmetric-type

Hi David,
On 01/13/2016 05:31 AM, David Howells wrote:
>> > +	pkey = keyring->payload.data[asym_crypto];
>> > +	if (!pkey) {
>> > +		key_put(keyring);
>> > +		goto out;
>> > +	}
>> > +
>> > +	err = setkey(private, pkey->key, pkey->keylen);
>> > +	key_put(keyring);
> Note that you may not assume that there's data there that you can use in this
> manner.  The key might be a pointer to some hardware device such as a TPM.  I
> have a TPM asymmetric subtype in progress.

So is there anything in place that can be used to tell what the key actually is?
The security/integrity/digsig_asymmetric.c is using this api in a similar way, so
if it is incorrect digsig_asymmetric shouldn't work neither.

> 
> I think this really needs to be driven from a keyctl() because you need to let
> the asymmetric subtype decide how it wants to handle this.  I would suggest
> adding KEYCTL_{ASYM_GETINFO,SIGN,VERIFY,ENCRYPT,DECRYPT} - the problem is how
> to pass sufficient arguments, how to decrypt the private key and what metadata
> needs to be passed vs what is inline with the data.

I agree, ideally keyctl should do the job for all the cases and request_key()
should just return a key data.
Thanks,
-- 
TS