lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:	Tue, 12 Feb 2013 10:43:22 -0500
From:	Vlad Yasevich <vyasevich@...il.com>
To:	Daniel Borkmann <dborkman@...hat.com>
CC:	davem@...emloft.net, linux-sctp@...r.kernel.org,
	netdev@...r.kernel.org, Neil Horman <nhorman@...driver.com>,
	Vlad Yasevich <vyasevic@...hat.com>
Subject: Re: [PATCH net-next v2] net: sctp: remove unused multiple cookie
 keys

On 02/12/2013 10:15 AM, Daniel Borkmann wrote:
> Vlad says: The whole multiple cookie keys code is completely unused
> and has been all this time. Noone uses anything other then the
> secret_key[0] since there is no changeover support anywhere.
>
> Thus, for now clean up its left-over fragments.
>
> Cc: Neil Horman <nhorman@...driver.com>
> Cc: Vlad Yasevich <vyasevic@...hat.com>

Acked-by: Vlad Yasevich <vyasevich@...il.com>

Thanks
-vlad

> Signed-off-by: Daniel Borkmann <dborkman@...hat.com>
> ---
>   include/net/sctp/constants.h |  2 +-
>   include/net/sctp/structs.h   |  5 +----
>   net/sctp/endpointola.c       |  9 ++-------
>   net/sctp/sm_make_chunk.c     | 31 +++++++------------------------
>   4 files changed, 11 insertions(+), 36 deletions(-)
>
> diff --git a/include/net/sctp/constants.h b/include/net/sctp/constants.h
> index c29707d..a7dd5c5 100644
> --- a/include/net/sctp/constants.h
> +++ b/include/net/sctp/constants.h
> @@ -303,7 +303,7 @@ enum { SCTP_MAX_GABS = 16 };
>                                            * to which we will raise the P-MTU.
>   					 */
>   #define SCTP_DEFAULT_MINSEGMENT 512	/* MTU size ... if no mtu disc */
> -#define SCTP_HOW_MANY_SECRETS 2		/* How many secrets I keep */
> +
>   #define SCTP_SECRET_SIZE 32		/* Number of octets in a 256 bits. */
>
>   #define SCTP_SIGNATURE_SIZE 20	        /* size of a SLA-1 signature */
> diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
> index fdeb85a..0e0f9d2 100644
> --- a/include/net/sctp/structs.h
> +++ b/include/net/sctp/structs.h
> @@ -1236,10 +1236,7 @@ struct sctp_endpoint {
>   	 *	      Discussion in [RFC1750] can be helpful in
>   	 *	      selection of the key.
>   	 */
> -	__u8 secret_key[SCTP_HOW_MANY_SECRETS][SCTP_SECRET_SIZE];
> -	int current_key;
> -	int last_key;
> -	int key_changed_at;
> +	__u8 secret_key[SCTP_SECRET_SIZE];
>
>    	/* digest:  This is a digest of the sctp cookie.  This field is
>    	 * 	    only used on the receive path when we try to validate
> diff --git a/net/sctp/endpointola.c b/net/sctp/endpointola.c
> index 1a9c5fb..73aad3d 100644
> --- a/net/sctp/endpointola.c
> +++ b/net/sctp/endpointola.c
> @@ -151,9 +151,7 @@ static struct sctp_endpoint *sctp_endpoint_init(struct sctp_endpoint *ep,
>   	ep->rcvbuf_policy = net->sctp.rcvbuf_policy;
>
>   	/* Initialize the secret key used with cookie. */
> -	get_random_bytes(&ep->secret_key[0], SCTP_SECRET_SIZE);
> -	ep->last_key = ep->current_key = 0;
> -	ep->key_changed_at = jiffies;
> +	get_random_bytes(ep->secret_key, sizeof(ep->secret_key));
>
>   	/* SCTP-AUTH extensions*/
>   	INIT_LIST_HEAD(&ep->endpoint_shared_keys);
> @@ -249,8 +247,6 @@ void sctp_endpoint_free(struct sctp_endpoint *ep)
>   /* Final destructor for endpoint.  */
>   static void sctp_endpoint_destroy(struct sctp_endpoint *ep)
>   {
> -	int i;
> -
>   	SCTP_ASSERT(ep->base.dead, "Endpoint is not dead", return);
>
>   	/* Free up the HMAC transform. */
> @@ -273,8 +269,7 @@ static void sctp_endpoint_destroy(struct sctp_endpoint *ep)
>   	sctp_inq_free(&ep->base.inqueue);
>   	sctp_bind_addr_free(&ep->base.bind_addr);
>
> -	for (i = 0; i < SCTP_HOW_MANY_SECRETS; ++i)
> -		memset(&ep->secret_key[i], 0, SCTP_SECRET_SIZE);
> +	memset(ep->secret_key, 0, sizeof(ep->secret_key));
>
>   	/* Remove and free the port */
>   	if (sctp_sk(ep->base.sk)->bind_hash)
> diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c
> index e1c5fc2..a193f3b 100644
> --- a/net/sctp/sm_make_chunk.c
> +++ b/net/sctp/sm_make_chunk.c
> @@ -1589,8 +1589,6 @@ static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
>   	struct sctp_signed_cookie *cookie;
>   	struct scatterlist sg;
>   	int headersize, bodysize;
> -	unsigned int keylen;
> -	char *key;
>
>   	/* Header size is static data prior to the actual cookie, including
>   	 * any padding.
> @@ -1650,12 +1648,11 @@ static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
>
>   		/* Sign the message.  */
>   		sg_init_one(&sg, &cookie->c, bodysize);
> -		keylen = SCTP_SECRET_SIZE;
> -		key = (char *)ep->secret_key[ep->current_key];
>   		desc.tfm = sctp_sk(ep->base.sk)->hmac;
>   		desc.flags = 0;
>
> -		if (crypto_hash_setkey(desc.tfm, key, keylen) ||
> +		if (crypto_hash_setkey(desc.tfm, ep->secret_key,
> +				       sizeof(ep->secret_key)) ||
>   		    crypto_hash_digest(&desc, &sg, bodysize, cookie->signature))
>   			goto free_cookie;
>   	}
> @@ -1682,8 +1679,7 @@ struct sctp_association *sctp_unpack_cookie(
>   	int headersize, bodysize, fixed_size;
>   	__u8 *digest = ep->digest;
>   	struct scatterlist sg;
> -	unsigned int keylen, len;
> -	char *key;
> +	unsigned int len;
>   	sctp_scope_t scope;
>   	struct sk_buff *skb = chunk->skb;
>   	struct timeval tv;
> @@ -1718,34 +1714,21 @@ struct sctp_association *sctp_unpack_cookie(
>   		goto no_hmac;
>
>   	/* Check the signature.  */
> -	keylen = SCTP_SECRET_SIZE;
>   	sg_init_one(&sg, bear_cookie, bodysize);
> -	key = (char *)ep->secret_key[ep->current_key];
>   	desc.tfm = sctp_sk(ep->base.sk)->hmac;
>   	desc.flags = 0;
>
>   	memset(digest, 0x00, SCTP_SIGNATURE_SIZE);
> -	if (crypto_hash_setkey(desc.tfm, key, keylen) ||
> +	if (crypto_hash_setkey(desc.tfm, ep->secret_key,
> +			       sizeof(ep->secret_key)) ||
>   	    crypto_hash_digest(&desc, &sg, bodysize, digest)) {
>   		*error = -SCTP_IERROR_NOMEM;
>   		goto fail;
>   	}
>
>   	if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
> -		/* Try the previous key. */
> -		key = (char *)ep->secret_key[ep->last_key];
> -		memset(digest, 0x00, SCTP_SIGNATURE_SIZE);
> -		if (crypto_hash_setkey(desc.tfm, key, keylen) ||
> -		    crypto_hash_digest(&desc, &sg, bodysize, digest)) {
> -			*error = -SCTP_IERROR_NOMEM;
> -			goto fail;
> -		}
> -
> -		if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
> -			/* Yikes!  Still bad signature! */
> -			*error = -SCTP_IERROR_BAD_SIG;
> -			goto fail;
> -		}
> +		*error = -SCTP_IERROR_BAD_SIG;
> +		goto fail;
>   	}
>
>   no_hmac:
>

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Powered by blists - more mailing lists