From: joeyli Subject: Re: [PATCH V4 02/15] asymmetric keys: implement EMSA_PKCS1-v1_5-ENCODE in rsa Date: Thu, 26 Sep 2013 15:08:30 +0800 Message-ID: <1380179310.32302.58.camel@linux-s257.site> References: <1379206621-18639-1-git-send-email-jlee@suse.com> <1379206621-18639-3-git-send-email-jlee@suse.com> <20130923164931.GD6772@samsung.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-security-module-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-efi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-pm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-crypto-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, opensuse-kernel-stAJ6ESoqRxg9hUCZPvPmw@public.gmane.org, David Howells , "Rafael J. Wysocki" , Matthew Garrett To: Phil Carmody Return-path: In-Reply-To: <20130923164931.GD6772-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org> List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: List-Archive: List-Id: linux-crypto.vger.kernel.org Hi Phil,=20 First! Thanks for your time to review my patch! =E6=96=BC =E4=B8=80=EF=BC=8C2013-09-23 =E6=96=BC 19:49 +0300=EF=BC=8CPhil= Carmody =E6=8F=90=E5=88=B0=EF=BC=9A > On Sun, Sep 15, 2013 at 08:56:48AM +0800, Lee, Chun-Yi wrote: > > Implement EMSA_PKCS1-v1_5-ENCODE [RFC3447 sec 9.2] in rsa.c. It's the > > first step of signature generation operation (RSASSA-PKCS1-v1_5-SIGN)= . > >=20 > > This patch is temporary set emLen to pks->k, and temporary set EM to > > pks->S for debugging. We will replace the above values to real signat= ure > > after implement RSASP1. > >=20 > > The naming of EMSA_PKCS1_v1_5_ENCODE and the variables used in this f= unction > > accord PKCS#1 spec but not follow kernel naming convention, it useful= when look > > at them with spec. > >=20 > > Reference: ftp://ftp.rsasecurity.com/pub/pkcs/pkcs-1v2/pkcs1ietffinal= .txt > > Reference: http://www.emc.com/collateral/white-papers/h11300-pkcs-1v2= -2-rsa-cryptography-standard-wp.pdf > >=20 > > V2: >=20 > You're now at V4. The V4 is for whole patchset, I didn't do any modify in this patch in this version. The version define maybe confuse between separate and whole patchset, I will avoid it. >=20 > > - Clean up naming of variable: replace _EM by EM, replace EM by EM_tm= p. > > - Add comment to EMSA_PKCS1-v1_5-ENCODE function. > >=20 > > Cc: Pavel Machek > > Reviewed-by: Jiri Kosina > > Signed-off-by: Lee, Chun-Yi > > --- > > crypto/asymmetric_keys/rsa.c | 163 ++++++++++++++++++++++++++++++++= +++++++++- > > include/crypto/public_key.h | 2 + > > 2 files changed, 164 insertions(+), 1 deletions(-) > >=20 > > diff --git a/crypto/asymmetric_keys/rsa.c b/crypto/asymmetric_keys/rs= a.c > > index 47f3be4..352ba45 100644 > > --- a/crypto/asymmetric_keys/rsa.c > > +++ b/crypto/asymmetric_keys/rsa.c > > @@ -13,6 +13,7 @@ > > #include > > #include > > #include > > +#include > > #include "public_key.h" > > #include "private_key.h" > > =20 > > @@ -152,6 +153,132 @@ static int RSA_I2OSP(MPI x, size_t xLen, u8 **_= X) > > } > > =20 > > /* > > + * EMSA_PKCS1-v1_5-ENCODE [RFC3447 sec 9.2] > > + * @M: message to be signed, an octet string > > + * @emLen: intended length in octets of the encoded message > > + * @hash_algo: hash function (option) > > + * @hash: true means hash M, otherwise M is already a digest > > + * @EM: encoded message, an octet string of length emLen > > + * > > + * This function is a implementation of the EMSA-PKCS1-v1_5 encoding= operation > > + * in RSA PKCS#1 spec. It used by the signautre generation operation= of > > + * RSASSA-PKCS1-v1_5 to encode message M to encoded message EM. > > + * > > + * The variables used in this function accord PKCS#1 spec but not fo= llow kernel > > + * naming convention, it useful when look at them with spec. > > + */ > > +static int EMSA_PKCS1_v1_5_ENCODE(const u8 *M, size_t emLen, > > + enum pkey_hash_algo hash_algo, const bool hash, > > + u8 **EM, struct public_key_signature *pks) > > +{ > > + u8 *digest; > > + struct crypto_shash *tfm; > > + struct shash_desc *desc; > > + size_t digest_size, desc_size; > > + size_t tLen; > > + u8 *T, *PS, *EM_tmp; > > + int i, ret; > > + > > + pr_info("EMSA_PKCS1_v1_5_ENCODE start\n"); > > + > > + if (!RSA_ASN1_templates[hash_algo].data) > > + ret =3D -ENOTSUPP; >=20 > ... >=20 > > + else > > + pks->pkey_hash_algo =3D hash_algo; > > + > > + /* 1) Apply the hash function to the message M to produce a hash va= lue H */ > > + tfm =3D crypto_alloc_shash(pkey_hash_algo[hash_algo], 0, 0); > > + if (IS_ERR(tfm)) > > + return (PTR_ERR(tfm) =3D=3D -ENOENT) ? -ENOPKG : PTR_ERR(tfm); > > + > > + desc_size =3D crypto_shash_descsize(tfm) + sizeof(*desc); > > + digest_size =3D crypto_shash_digestsize(tfm); > > + > > + ret =3D -ENOMEM; >=20 > The earlier "ret =3D -ENOTSUPP;" is either unused because you return at= the IS_ERR, > or unused because you overwrite it here. I'm a little disappointed that > the compiler didn't recognise that something was assigned to a value th= at=20 > is never used. >=20 > Phil Yes, Dmitry also pointed out this issue, I should not go on the hash process if the hash algorithm didn't support. I will change fix this problem in next version.=20 Thanks a lot! Joey Lee --=20 To unsubscribe, e-mail: opensuse-kernel+unsubscribe-stAJ6ESoqRxg9hUCZPvPmw@public.gmane.org To contact the owner, e-mail: opensuse-kernel+owner-stAJ6ESoqRxg9hUCZPvPmw@public.gmane.org