From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eu-smtp-delivery-151.mimecast.com (eu-smtp-delivery-151.mimecast.com [185.58.85.151]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C92BC72 for ; Thu, 22 Jul 2021 15:30:14 +0000 (UTC) Received: from AcuMS.aculab.com (156.67.243.121 [156.67.243.121]) (Using TLS) by relay.mimecast.com with ESMTP id uk-mta-154-E8XI6R9BMwq2Wfp8lcAmRg-1; Thu, 22 Jul 2021 16:30:10 +0100 X-MC-Unique: E8XI6R9BMwq2Wfp8lcAmRg-1 Received: from AcuMS.Aculab.com (fd9f:af1c:a25b:0:994c:f5c2:35d6:9b65) by AcuMS.aculab.com (fd9f:af1c:a25b:0:994c:f5c2:35d6:9b65) with Microsoft SMTP Server (TLS) id 15.0.1497.23; Thu, 22 Jul 2021 16:30:09 +0100 Received: from AcuMS.Aculab.com ([fe80::994c:f5c2:35d6:9b65]) by AcuMS.aculab.com ([fe80::994c:f5c2:35d6:9b65%12]) with mapi id 15.00.1497.023; Thu, 22 Jul 2021 16:30:09 +0100 From: David Laight To: "'Fabio M. De Francesco'" , Larry Finger , Greg Kroah-Hartman , "linux-staging@lists.linux.dev" , "linux-kernel@vger.kernel.org" Subject: RE: [PATCH v3 1/2] staging: rtl8188eu: Replace a custom function with crc32_le() Thread-Topic: [PATCH v3 1/2] staging: rtl8188eu: Replace a custom function with crc32_le() Thread-Index: AQHXfiEvucvRPynR106nc+5J/iJ13qtPHROQ Date: Thu, 22 Jul 2021 15:30:08 +0000 Message-ID: References: <20210721110052.26376-1-fmdefrancesco@gmail.com> <20210721110052.26376-2-fmdefrancesco@gmail.com> In-Reply-To: <20210721110052.26376-2-fmdefrancesco@gmail.com> Accept-Language: en-GB, en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.202.205.107] Precedence: bulk X-Mailing-List: linux-staging@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=C51A453 smtp.mailfrom=david.laight@aculab.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: aculab.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable From: Fabio M. De Francesco > Sent: 21 July 2021 12:01 >=20 > Use crc32_le() in place of the custom getcrc32(). >=20 ... > @@ -609,14 +595,15 @@ u32=09rtw_tkip_encrypt(struct adapter *padapter, st= ruct xmit_frame > *pxmitframe) >=20 > =09=09=09=09if ((curfragnum + 1) =3D=3D pattrib->nr_frags) {=09/* 4 the = last fragment */ > =09=09=09=09=09length =3D pattrib->last_txcmdsz - pattrib->hdrlen - patt= rib->iv_len - > pattrib->icv_len; > -=09=09=09=09=09*((__le32 *)crc) =3D getcrc32(payload, length);/* modifie= d by Amy*/ > +=09=09=09=09=09*((__le32 *)crc) =3D cpu_to_le32(~crc32_le(~0, payload, l= ength)); >=20 > =09=09=09=09=09arcfour_init(&mycontext, rc4key, 16); > =09=09=09=09=09arcfour_encrypt(&mycontext, payload, payload, length); > =09=09=09=09=09arcfour_encrypt(&mycontext, payload + length, crc, 4); > =09=09=09=09} else { > =09=09=09=09=09length =3D pxmitpriv->frag_len - pattrib->hdrlen - pattri= b->iv_len - > pattrib->icv_len; > -=09=09=09=09=09*((__le32 *)crc) =3D getcrc32(payload, length);/* modifie= d by Amy*/ > +=09=09=09=09=09*((__le32 *)crc) =3D cpu_to_le32(~crc32_le(~0, payload, l= ength)); > + > =09=09=09=09=09arcfour_init(&mycontext, rc4key, 16); > =09=09=09=09=09arcfour_encrypt(&mycontext, payload, payload, length); > =09=09=09=09=09arcfour_encrypt(&mycontext, payload + length, crc, 4); Change crc to be __le32, kill the casts and pass &crc in the last call. > @@ -682,7 +669,7 @@ u32 rtw_tkip_decrypt(struct adapter *padapter, struct= recv_frame *precvframe) > =09=09=09arcfour_init(&mycontext, rc4key, 16); > =09=09=09arcfour_encrypt(&mycontext, payload, payload, length); >=20 > -=09=09=09*((__le32 *)crc) =3D getcrc32(payload, length - 4); > +=09=09=09*((__le32 *)crc) =3D cpu_to_le32(~crc32_le(~0, payload, length = - 4)); >=20 > =09=09=09if (crc[3] !=3D payload[length - 1] || > =09=09=09 crc[2] !=3D payload[length - 2] || You could to the same here, or make crc u32, remove the cpu_to_le32() and use get_unaligned_u32(payload + length - 4) (or whatever it is called). But it is much better to do: =09crc =3D crc32_le(~0, payload, length); =09if (crc !=3D VALID_CRC32) =09=09res =3D _FAIL; You can lookup VALID_CRC32, but it is crc32_le(0, "\xff\xff\xff\xff", 4); =09David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1= PT, UK Registration No: 1397386 (Wales)