From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephan Mueller Subject: Re: [PATCH 6/15] crypto: rng - Mark crypto_rng_reset seed as const Date: Mon, 20 Apr 2015 13:48:51 +0200 Message-ID: <2772920.G0U3hXTNm6@myon.chronox.de> References: <20150420053515.GA18444@gondor.apana.org.au> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Cc: Linux Crypto Mailing List To: Herbert Xu Return-path: Received: from mail.eperm.de ([89.247.134.16]:34221 "EHLO mail.eperm.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754734AbbDTLs5 (ORCPT ); Mon, 20 Apr 2015 07:48:57 -0400 In-Reply-To: Sender: linux-crypto-owner@vger.kernel.org List-ID: Am Montag, 20. April 2015, 13:39:05 schrieb Herbert Xu: Hi Herbert, > There is no reason why crypto_rng_reset should modify the seed > so this patch marks it as const. Since our algorithms don't > export a const seed function yet we have to go through some > contortions for now. > > Signed-off-by: Herbert Xu > --- > > crypto/rng.c | 27 +++++++++++++++++++++++++-- > include/crypto/rng.h | 9 +++------ > 2 files changed, 28 insertions(+), 8 deletions(-) > > diff --git a/crypto/rng.c b/crypto/rng.c > index 4514d37..618fa4d 100644 > --- a/crypto/rng.c > +++ b/crypto/rng.c > @@ -42,7 +42,29 @@ static int generate(struct crypto_rng *tfm, const u8 > *src, unsigned int slen, return crypto_rng_alg(tfm)->rng_make_random(tfm, > dst, dlen); > } > > -static int rngapi_reset(struct crypto_rng *tfm, u8 *seed, unsigned int > slen) +static int rngapi_reset(struct crypto_rng *tfm, const u8 *seed, > + unsigned int slen) > +{ > + u8 *buf = NULL; > + u8 *src = (u8 *)seed; > + int err; > + > + if (slen) { > + buf = kmalloc(slen, GFP_KERNEL); > + if (!buf) > + return -ENOMEM; > + > + memcpy(buf, seed, slen); > + src = buf; > + } > + > + err = crypto_rng_alg(tfm)->rng_reset(tfm, src, slen); > + > + kfree(buf); Shouldn't kzfree be here? Seed data is sensitive data. > + return err; > +} > + > +int crypto_rng_reset(struct crypto_rng *tfm, const u8 *seed, unsigned int > slen) { > u8 *buf = NULL; > int err; > @@ -56,11 +78,12 @@ static int rngapi_reset(struct crypto_rng *tfm, u8 > *seed, unsigned int slen) seed = buf; > } > > - err = crypto_rng_alg(tfm)->rng_reset(tfm, seed, slen); > + err = tfm->seed(tfm, seed, slen); > > kfree(buf); > return err; > } > +EXPORT_SYMBOL_GPL(crypto_rng_reset); > > static int crypto_rng_init_tfm(struct crypto_tfm *tfm) > { > diff --git a/include/crypto/rng.h b/include/crypto/rng.h > index f20f068..7fca371 100644 > --- a/include/crypto/rng.h > +++ b/include/crypto/rng.h > @@ -19,7 +19,7 @@ struct crypto_rng { > int (*generate)(struct crypto_rng *tfm, > const u8 *src, unsigned int slen, > u8 *dst, unsigned int dlen); > - int (*seed)(struct crypto_rng *tfm, u8 *seed, unsigned int slen); > + int (*seed)(struct crypto_rng *tfm, const u8 *seed, unsigned int slen); > struct crypto_tfm base; > }; > > @@ -139,11 +139,8 @@ static inline int crypto_rng_get_bytes(struct > crypto_rng *tfm, * > * Return: 0 if the setting of the key was successful; < 0 if an error > occurred */ > -static inline int crypto_rng_reset(struct crypto_rng *tfm, > - u8 *seed, unsigned int slen) > -{ > - return tfm->seed(tfm, seed, slen); > -} > +int crypto_rng_reset(struct crypto_rng *tfm, const u8 *seed, > + unsigned int slen); > > /** > * crypto_rng_seedsize() - obtain seed size of RNG > -- > To unsubscribe from this list: send the line "unsubscribe linux-crypto" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Ciao Stephan