From: Ard Biesheuvel <ard.biesheuvel@linaro.org>
To: Kees Cook <keescook@chromium.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>,
Eric Biggers <ebiggers@google.com>,
"open list:HARDWARE RANDOM NUMBER GENERATOR CORE"
<linux-crypto@vger.kernel.org>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH crypto-next 01/23] crypto: skcipher - Introduce crypto_sync_skcipher
Date: Mon, 24 Sep 2018 13:48:30 +0200 [thread overview]
Message-ID: <CAKv+Gu8v0e-6Xv4_1W5qcUV_3Hed9rTXmJ9vzYTf1jEHnyaxaQ@mail.gmail.com> (raw)
In-Reply-To: <20180919021100.3380-2-keescook@chromium.org>
On Wed, 19 Sep 2018 at 04:11, Kees Cook <keescook@chromium.org> wrote:
>
> In preparation for removal of VLAs due to skcipher requests on the stack
> via SKCIPHER_REQUEST_ON_STACK() usage, this introduces the infrastructure
> for the "sync skcipher" tfm, which is for handling the on-stack cases of
> skcipher, which are always non-ASYNC and have a known limited request
> size.
>
> The crypto API additions:
>
> struct crypto_sync_skcipher (wrapper for struct crypto_skcipher)
> crypto_alloc_sync_skcipher()
> crypto_free_sync_skcipher()
> crypto_sync_skcipher_setkey()
> crypto_sync_skcipher_get_flags()
> crypto_sync_skcipher_set_flags()
> crypto_sync_skcipher_clear_flags()
> crypto_sync_skcipher_blocksize()
> crypto_sync_skcipher_ivsize()
> crypto_sync_skcipher_reqtfm()
> skcipher_request_set_sync_tfm()
> SYNC_SKCIPHER_REQUEST_ON_STACK() (with tfm type check)
>
> Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> ---
> crypto/skcipher.c | 24 +++++++++++++
> include/crypto/skcipher.h | 75 +++++++++++++++++++++++++++++++++++++++
> 2 files changed, 99 insertions(+)
>
> diff --git a/crypto/skcipher.c b/crypto/skcipher.c
> index 0bd8c6caa498..4caab81d2d02 100644
> --- a/crypto/skcipher.c
> +++ b/crypto/skcipher.c
> @@ -949,6 +949,30 @@ struct crypto_skcipher *crypto_alloc_skcipher(const char *alg_name,
> }
> EXPORT_SYMBOL_GPL(crypto_alloc_skcipher);
>
> +struct crypto_sync_skcipher *crypto_alloc_sync_skcipher(
> + const char *alg_name, u32 type, u32 mask)
> +{
> + struct crypto_skcipher *tfm;
> +
> + /* Only sync algorithms allowed. */
> + mask |= CRYPTO_ALG_ASYNC;
> +
> + tfm = crypto_alloc_tfm(alg_name, &crypto_skcipher_type2, type, mask);
> +
> + /*
> + * Make sure we do not allocate something that might get used with
> + * an on-stack request: check the request size.
> + */
> + if (!IS_ERR(tfm) && WARN_ON(crypto_skcipher_reqsize(tfm) >
> + MAX_SYNC_SKCIPHER_REQSIZE)) {
> + crypto_free_skcipher(tfm);
> + return ERR_PTR(-EINVAL);
> + }
> +
> + return (struct crypto_sync_skcipher *)tfm;
> +}
> +EXPORT_SYMBOL_GPL(crypto_alloc_sync_skcipher);
> +
> int crypto_has_skcipher2(const char *alg_name, u32 type, u32 mask)
> {
> return crypto_type_has_alg(alg_name, &crypto_skcipher_type2,
> diff --git a/include/crypto/skcipher.h b/include/crypto/skcipher.h
> index 2f327f090c3e..d00ce90dc7da 100644
> --- a/include/crypto/skcipher.h
> +++ b/include/crypto/skcipher.h
> @@ -65,6 +65,10 @@ struct crypto_skcipher {
> struct crypto_tfm base;
> };
>
> +struct crypto_sync_skcipher {
> + struct crypto_skcipher base;
> +};
> +
> /**
> * struct skcipher_alg - symmetric key cipher definition
> * @min_keysize: Minimum key size supported by the transformation. This is the
> @@ -139,6 +143,19 @@ struct skcipher_alg {
> struct crypto_alg base;
> };
>
> +#define MAX_SYNC_SKCIPHER_REQSIZE 384
> +/*
> + * This performs a type-check against the "tfm" argument to make sure
> + * all users have the correct skcipher tfm for doing on-stack requests.
> + */
> +#define SYNC_SKCIPHER_REQUEST_ON_STACK(name, tfm) \
> + char __##name##_desc[sizeof(struct skcipher_request) + \
> + MAX_SYNC_SKCIPHER_REQSIZE + \
> + (!(sizeof((struct crypto_sync_skcipher *)1 == \
> + (typeof(tfm))1))) \
> + ] CRYPTO_MINALIGN_ATTR; \
> + struct skcipher_request *name = (void *)__##name##_desc
> +
> #define SKCIPHER_REQUEST_ON_STACK(name, tfm) \
> char __##name##_desc[sizeof(struct skcipher_request) + \
> crypto_skcipher_reqsize(tfm)] CRYPTO_MINALIGN_ATTR; \
> @@ -197,6 +214,9 @@ static inline struct crypto_skcipher *__crypto_skcipher_cast(
> struct crypto_skcipher *crypto_alloc_skcipher(const char *alg_name,
> u32 type, u32 mask);
>
> +struct crypto_sync_skcipher *crypto_alloc_sync_skcipher(const char *alg_name,
> + u32 type, u32 mask);
> +
> static inline struct crypto_tfm *crypto_skcipher_tfm(
> struct crypto_skcipher *tfm)
> {
> @@ -212,6 +232,11 @@ static inline void crypto_free_skcipher(struct crypto_skcipher *tfm)
> crypto_destroy_tfm(tfm, crypto_skcipher_tfm(tfm));
> }
>
> +static inline void crypto_free_sync_skcipher(struct crypto_sync_skcipher *tfm)
> +{
> + crypto_free_skcipher(&tfm->base);
> +}
> +
> /**
> * crypto_has_skcipher() - Search for the availability of an skcipher.
> * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
> @@ -280,6 +305,12 @@ static inline unsigned int crypto_skcipher_ivsize(struct crypto_skcipher *tfm)
> return tfm->ivsize;
> }
>
> +static inline unsigned int crypto_sync_skcipher_ivsize(
> + struct crypto_sync_skcipher *tfm)
> +{
> + return crypto_skcipher_ivsize(&tfm->base);
> +}
> +
> static inline unsigned int crypto_skcipher_alg_chunksize(
> struct skcipher_alg *alg)
> {
> @@ -356,6 +387,12 @@ static inline unsigned int crypto_skcipher_blocksize(
> return crypto_tfm_alg_blocksize(crypto_skcipher_tfm(tfm));
> }
>
> +static inline unsigned int crypto_sync_skcipher_blocksize(
> + struct crypto_sync_skcipher *tfm)
> +{
> + return crypto_skcipher_blocksize(&tfm->base);
> +}
> +
> static inline unsigned int crypto_skcipher_alignmask(
> struct crypto_skcipher *tfm)
> {
> @@ -379,6 +416,24 @@ static inline void crypto_skcipher_clear_flags(struct crypto_skcipher *tfm,
> crypto_tfm_clear_flags(crypto_skcipher_tfm(tfm), flags);
> }
>
> +static inline u32 crypto_sync_skcipher_get_flags(
> + struct crypto_sync_skcipher *tfm)
> +{
> + return crypto_skcipher_get_flags(&tfm->base);
> +}
> +
> +static inline void crypto_sync_skcipher_set_flags(
> + struct crypto_sync_skcipher *tfm, u32 flags)
> +{
> + crypto_skcipher_set_flags(&tfm->base, flags);
> +}
> +
> +static inline void crypto_sync_skcipher_clear_flags(
> + struct crypto_sync_skcipher *tfm, u32 flags)
> +{
> + crypto_skcipher_clear_flags(&tfm->base, flags);
> +}
> +
> /**
> * crypto_skcipher_setkey() - set key for cipher
> * @tfm: cipher handle
> @@ -401,6 +456,12 @@ static inline int crypto_skcipher_setkey(struct crypto_skcipher *tfm,
> return tfm->setkey(tfm, key, keylen);
> }
>
> +static inline int crypto_sync_skcipher_setkey(struct crypto_sync_skcipher *tfm,
> + const u8 *key, unsigned int keylen)
> +{
> + return crypto_skcipher_setkey(&tfm->base, key, keylen);
> +}
> +
> static inline unsigned int crypto_skcipher_default_keysize(
> struct crypto_skcipher *tfm)
> {
> @@ -422,6 +483,14 @@ static inline struct crypto_skcipher *crypto_skcipher_reqtfm(
> return __crypto_skcipher_cast(req->base.tfm);
> }
>
> +static inline struct crypto_sync_skcipher *crypto_sync_skcipher_reqtfm(
> + struct skcipher_request *req)
> +{
> + struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
> +
> + return container_of(tfm, struct crypto_sync_skcipher, base);
> +}
> +
> /**
> * crypto_skcipher_encrypt() - encrypt plaintext
> * @req: reference to the skcipher_request handle that holds all information
> @@ -500,6 +569,12 @@ static inline void skcipher_request_set_tfm(struct skcipher_request *req,
> req->base.tfm = crypto_skcipher_tfm(tfm);
> }
>
> +static inline void skcipher_request_set_sync_tfm(struct skcipher_request *req,
> + struct crypto_sync_skcipher *tfm)
> +{
> + skcipher_request_set_tfm(req, &tfm->base);
> +}
> +
> static inline struct skcipher_request *skcipher_request_cast(
> struct crypto_async_request *req)
> {
> --
> 2.17.1
>
next prev parent reply other threads:[~2018-09-24 11:48 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-09-19 2:10 [PATCH crypto-next 00/23] crypto: skcipher - Remove VLA usage Kees Cook
2018-09-19 2:10 ` [PATCH crypto-next 01/23] crypto: skcipher - Introduce crypto_sync_skcipher Kees Cook
2018-09-24 11:48 ` Ard Biesheuvel [this message]
2018-09-19 2:10 ` [PATCH crypto-next 02/23] gss_krb5: Remove VLA usage of skcipher Kees Cook
2018-09-19 2:10 ` [PATCH crypto-next 03/23] lib80211: " Kees Cook
2018-09-19 20:37 ` Johannes Berg
2018-09-19 2:10 ` [PATCH crypto-next 04/23] mac802154: " Kees Cook
2018-09-19 2:10 ` [PATCH crypto-next 05/23] s390/crypto: " Kees Cook
2018-09-19 2:10 ` [PATCH crypto-next 06/23] x86/fpu: " Kees Cook
2018-09-24 11:45 ` Ard Biesheuvel
2018-09-24 17:35 ` Kees Cook
2018-09-19 2:10 ` [PATCH crypto-next 07/23] block: cryptoloop: " Kees Cook
2018-09-24 11:52 ` Ard Biesheuvel
2018-09-24 17:53 ` Kees Cook
2018-09-25 9:25 ` Ard Biesheuvel
2018-09-25 16:03 ` Jens Axboe
2018-09-25 16:16 ` Ard Biesheuvel
2018-09-25 16:32 ` Jens Axboe
2018-09-26 8:19 ` Ard Biesheuvel
2018-09-19 2:10 ` [PATCH crypto-next 08/23] libceph: " Kees Cook
2018-09-19 2:10 ` [PATCH crypto-next 09/23] ppp: mppe: " Kees Cook
2018-09-19 2:10 ` [PATCH crypto-next 10/23] rxrpc: " Kees Cook
2018-09-19 2:10 ` [PATCH crypto-next 11/23] wusb: " Kees Cook
2018-09-20 10:39 ` Greg Kroah-Hartman
2018-09-19 2:10 ` [PATCH crypto-next 12/23] crypto: ccp - " Kees Cook
2018-09-19 2:10 ` [PATCH crypto-next 13/23] crypto: vmx " Kees Cook
2018-09-19 2:10 ` [PATCH crypto-next 14/23] crypto: null " Kees Cook
2018-09-19 2:10 ` [PATCH crypto-next 15/23] crypto: cryptd " Kees Cook
2018-09-19 2:10 ` [PATCH crypto-next 16/23] crypto: sahara " Kees Cook
2018-09-19 2:10 ` [PATCH crypto-next 17/23] crypto: qce " Kees Cook
2018-09-19 2:10 ` [PATCH crypto-next 18/23] crypto: artpec6 " Kees Cook
2018-09-23 12:13 ` Lars Persson
2018-09-19 2:10 ` [PATCH crypto-next 19/23] crypto: chelsio " Kees Cook
2018-09-19 2:10 ` [PATCH crypto-next 20/23] crypto: mxs-dcp " Kees Cook
2018-09-19 2:10 ` [PATCH crypto-next 21/23] crypto: omap-aes " Kees Cook
2018-09-19 2:10 ` [PATCH crypto-next 22/23] crypto: picoxcell " Kees Cook
2018-09-19 2:11 ` [PATCH crypto-next 23/23] crypto: skcipher - Remove SKCIPHER_REQUEST_ON_STACK() Kees Cook
2018-09-25 0:49 ` [PATCH crypto-next 00/23] crypto: skcipher - Remove VLA usage Kees Cook
2018-09-25 4:49 ` Herbert Xu
2018-09-25 15:39 ` Kees Cook
2018-09-28 5:08 ` Herbert Xu
2018-09-28 16:13 ` Kees Cook
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=CAKv+Gu8v0e-6Xv4_1W5qcUV_3Hed9rTXmJ9vzYTf1jEHnyaxaQ@mail.gmail.com \
--to=ard.biesheuvel@linaro.org \
--cc=ebiggers@google.com \
--cc=herbert@gondor.apana.org.au \
--cc=keescook@chromium.org \
--cc=linux-crypto@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).