From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Howells Date: Wed, 16 Jan 2019 16:15:20 +0000 Subject: Re: [RFC PATCH 4/4] crypto: Add EC-RDSA algorithm Message-Id: <21602.1547655320@warthog.procyon.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit List-Id: References: <20190107090449.d364ii24zervlsfq@sole.flsd.net> <20190106133608.820-1-vt@altlinux.org> <1893001.R2IGJoHzOM@positron.chronox.de> <20190107080710.r4bh7gkqdysxmlnn@sole.flsd.net> <1714084.mfT8VG1pOj@tauon.chronox.de> In-Reply-To: <20190107090449.d364ii24zervlsfq@sole.flsd.net> To: Vitaly Chikunov Cc: dhowells@redhat.com, Stephan Mueller , Herbert Xu , Mimi Zohar , Dmitry Kasatkin , linux-integrity@vger.kernel.org, keyrings@vger.kernel.org, linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org Vitaly Chikunov wrote: > > Regarding your comment (2), I am not sure I understand. Why do you say that > > the DER format cannot be parsed by the kernel's ASN.1 parser? For example, > > It can, but DER is stricter than BER. For example, in DER 'OCTET STRING' > length field should be encoded in just one byte if it's smaller than > 128, in BER it could be encoded in multiple encodings. This does not > seem like a big deal, though. With BER decoder an improperly DER-encoded > certificate could be successfully parsed. Whilst that is true, I don't think it's that big a deal. DER is a subset of BER, so a BER decoder ought to be able to parse it. Note that X.509 is supposed to be DER, but we use a BER decoder for that too. David