From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mimi Zohar Date: Wed, 27 Mar 2019 20:21:07 +0000 Subject: Re: [PATCH v8 10/10] integrity: support EC-RDSA signatures for asymmetric_verify Message-Id: <1553718067.4608.43.camel@linux.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit List-Id: References: <20190326125842.24110-1-vt@altlinux.org> <20190326125842.24110-11-vt@altlinux.org> <1553710220.4608.9.camel@linux.ibm.com> <20190327201441.ikw76qzpgzm6t35b@altlinux.org> In-Reply-To: <20190327201441.ikw76qzpgzm6t35b@altlinux.org> To: Vitaly Chikunov Cc: Herbert Xu , David Howells , Dmitry Kasatkin , linux-integrity@vger.kernel.org, keyrings@vger.kernel.org, linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org > > diff --git a/security/integrity/digsig_asymmetric.c b/security/integrity/digsig_asymmetric.c > > > index d775e03fbbcc..99080871eb9f 100644 > > > --- a/security/integrity/digsig_asymmetric.c > > > +++ b/security/integrity/digsig_asymmetric.c > > > @@ -104,9 +104,16 @@ int asymmetric_verify(struct key *keyring, const char *sig, > > > > > > memset(&pks, 0, sizeof(pks)); > > > > > > - pks.pkey_algo = "rsa"; > > > pks.hash_algo = hash_algo_name[hdr->hash_algo]; > > > - pks.encoding = "pkcs1"; > > > + if (hdr->hash_algo = HASH_ALGO_STREEBOG_256 || > > > + hdr->hash_algo = HASH_ALGO_STREEBOG_512) { > > > + /* EC-RDSA and Streebog should go together. */ > > > + pks.pkey_algo = "ecrdsa"; > > > + pks.encoding = "raw"; > > > > IMA signatures are stored as xattrs, making them persistent.  Support > > for streebog was upstreamed in linux-5.0.  This change would break > > existing systems using streebog.  As long as this is not yet a concern > > In what sense it would break systems? For example, if executable files are currently labeled with rsa/streebog signatures, then enforcing file data integrity I assume would break if the kernel uses ecrdsa/streebog. Mimi > > Unless kernel crashes or signature is recognized as valid, I think, it should > not be called a break. > > > Reviewed-by:  Mimi Zohar > > Thanks! > > > > > > + } else { > > > + pks.pkey_algo = "rsa"; > > > + pks.encoding = "pkcs1"; > > > + } > > > pks.digest = (u8 *)data; > > > pks.digest_size = datalen; > > > pks.s = hdr->sig; >