Received-SPF: pass (google.com: domain of linux-crypto-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley
        Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United
        Kingdom.
        Registered in England and Wales under Company Registration No. 3798903
From:   David Howells <dhowells@redhat.com>
In-Reply-To: <ZDkoiqPXwIRYmeF3@gondor.apana.org.au>
References: <ZDkoiqPXwIRYmeF3@gondor.apana.org.au> <ZDkUSESImVSUX0RW@gondor.apana.org.au> <ZDi1qjVpcpr2BZfN@gondor.apana.org.au> <48886D84-1A04-4B07-A666-BB56684E759F@oracle.com> <380323.1681314997@warthog.procyon.org.uk> <1078650.1681394138@warthog.procyon.org.uk> <1235770.1681462057@warthog.procyon.org.uk> <1239035.1681467430@warthog.procyon.org.uk>
To:     Herbert Xu <herbert@gondor.apana.org.au>
Cc:     dhowells@redhat.com, Chuck Lever III <chuck.lever@oracle.com>,
        Scott Mayhew <smayhew@redhat.com>,
        Ard Biesheuvel <ardb@kernel.org>,
        Jeff Layton <jlayton@kernel.org>,
        Linux NFS Mailing List <linux-nfs@vger.kernel.org>,
        "linux-crypto@vger.kernel.org" <linux-crypto@vger.kernel.org>
Subject: Re: Did the in-kernel Camellia or CMAC crypto implementation break?
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-ID: <1239685.1681468477.1@warthog.procyon.org.uk>
Date:   Fri, 14 Apr 2023 11:34:37 +0100
Message-ID: <1239686.1681468477@warthog.procyon.org.uk>
Precedence: bulk

Herbert Xu <herbert@gondor.apana.org.au> wrote:

> Interesting.  Could you outline how this new interface would work?

I'll write up an API doc for my code as I have it working and post that.

> And have you looked whether the aead interface could fit into your
> model?

Do you mean use the aead API rather than inventing my own?  Looking at aead.h,
there aren't enough bits in it as it stands:

	struct aead_alg {
		int (*setkey)(struct crypto_aead *tfm, const u8 *key,
			      unsigned int keylen);
		int (*setauthsize)(struct crypto_aead *tfm, unsigned int authsize);
		int (*encrypt)(struct aead_request *req);
		int (*decrypt)(struct aead_request *req);
		int (*init)(struct crypto_aead *tfm);
		void (*exit)(struct crypto_aead *tfm);

		unsigned int ivsize;
		unsigned int maxauthsize;
		unsigned int chunksize;

		struct crypto_alg base;
	};

In krb5, for encryption, there are two keys, not one, and no IV to be passed
in.  The code I have will insert a confounder and a checksum, which must have
space allowed for it.

David