diff mbox series

[v22,16/23] LSM: security_secid_to_secctx in netlink netfilter

Message ID 20201105004924.11651-17-casey@schaufler-ca.com
State Superseded
Headers show
Series None | expand

Commit Message

Casey Schaufler Nov. 5, 2020, 12:49 a.m. UTC 
Change netlink netfilter interfaces to use lsmcontext
pointers, and remove scaffolding.

Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: John Johansen <john.johansen@canonical.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: netdev@vger.kernel.org
Cc: netfilter-devel@vger.kernel.org
---
 net/netfilter/nfnetlink_queue.c | 37 +++++++++++++--------------------
 1 file changed, 14 insertions(+), 23 deletions(-)

Comments

Pablo Neira Ayuso Nov. 10, 2020, 1:37 p.m. UTC | #1 
Hi Casey,

On Wed, Nov 04, 2020 at 04:49:17PM -0800, Casey Schaufler wrote:
> Change netlink netfilter interfaces to use lsmcontext

> pointers, and remove scaffolding.

> 

> Reviewed-by: Kees Cook <keescook@chromium.org>

> Reviewed-by: John Johansen <john.johansen@canonical.com>

> Acked-by: Stephen Smalley <sds@tycho.nsa.gov>

> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>

> Cc: netdev@vger.kernel.org

> Cc: netfilter-devel@vger.kernel.org


You can carry this tag in your follow up patches.

Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>


Thanks.

> ---

>  net/netfilter/nfnetlink_queue.c | 37 +++++++++++++--------------------

>  1 file changed, 14 insertions(+), 23 deletions(-)

> 

> diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c

> index 84be5a49a157..0d8b83d84422 100644

> --- a/net/netfilter/nfnetlink_queue.c

> +++ b/net/netfilter/nfnetlink_queue.c

> @@ -301,15 +301,13 @@ static int nfqnl_put_sk_uidgid(struct sk_buff *skb, struct sock *sk)

>  	return -1;

>  }

>  

> -static u32 nfqnl_get_sk_secctx(struct sk_buff *skb, char **secdata)

> +static void nfqnl_get_sk_secctx(struct sk_buff *skb, struct lsmcontext *context)

>  {

> -	u32 seclen = 0;

>  #if IS_ENABLED(CONFIG_NETWORK_SECMARK)

>  	struct lsmblob blob;

> -	struct lsmcontext context = { };

>  

>  	if (!skb || !sk_fullsock(skb->sk))

> -		return 0;

> +		return;

>  

>  	read_lock_bh(&skb->sk->sk_callback_lock);

>  

> @@ -318,14 +316,12 @@ static u32 nfqnl_get_sk_secctx(struct sk_buff *skb, char **secdata)

>  		 * blob. security_secid_to_secctx() will know which security

>  		 * module to use to create the secctx.  */

>  		lsmblob_init(&blob, skb->secmark);

> -		security_secid_to_secctx(&blob, &context);

> -		*secdata = context.context;

> +		security_secid_to_secctx(&blob, context);

>  	}

>  

>  	read_unlock_bh(&skb->sk->sk_callback_lock);

> -	seclen = context.len;

>  #endif

> -	return seclen;

> +	return;

>  }

>  

>  static u32 nfqnl_get_bridge_size(struct nf_queue_entry *entry)

> @@ -398,12 +394,10 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,

>  	struct net_device *indev;

>  	struct net_device *outdev;

>  	struct nf_conn *ct = NULL;

> +	struct lsmcontext context = { };

>  	enum ip_conntrack_info ctinfo;

>  	struct nfnl_ct_hook *nfnl_ct;

>  	bool csum_verify;

> -	struct lsmcontext scaff; /* scaffolding */

> -	char *secdata = NULL;

> -	u32 seclen = 0;

>  

>  	size = nlmsg_total_size(sizeof(struct nfgenmsg))

>  		+ nla_total_size(sizeof(struct nfqnl_msg_packet_hdr))

> @@ -469,9 +463,9 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,

>  	}

>  

>  	if ((queue->flags & NFQA_CFG_F_SECCTX) && entskb->sk) {

> -		seclen = nfqnl_get_sk_secctx(entskb, &secdata);

> -		if (seclen)

> -			size += nla_total_size(seclen);

> +		nfqnl_get_sk_secctx(entskb, &context);

> +		if (context.len)

> +			size += nla_total_size(context.len);

>  	}

>  

>  	skb = alloc_skb(size, GFP_ATOMIC);

> @@ -604,7 +598,8 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,

>  	    nfqnl_put_sk_uidgid(skb, entskb->sk) < 0)

>  		goto nla_put_failure;

>  

> -	if (seclen && nla_put(skb, NFQA_SECCTX, seclen, secdata))

> +	if (context.len &&

> +	    nla_put(skb, NFQA_SECCTX, context.len, context.context))

>  		goto nla_put_failure;

>  

>  	if (ct && nfnl_ct->build(skb, ct, ctinfo, NFQA_CT, NFQA_CT_INFO) < 0)

> @@ -632,10 +627,8 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,

>  	}

>  

>  	nlh->nlmsg_len = skb->len;

> -	if (seclen) {

> -		lsmcontext_init(&scaff, secdata, seclen, 0);

> -		security_release_secctx(&scaff);

> -	}

> +	if (context.len)

> +		security_release_secctx(&context);

>  	return skb;

>  

>  nla_put_failure:

> @@ -643,10 +636,8 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,

>  	kfree_skb(skb);

>  	net_err_ratelimited("nf_queue: error creating packet message\n");

>  nlmsg_failure:

> -	if (seclen) {

> -		lsmcontext_init(&scaff, secdata, seclen, 0);

> -		security_release_secctx(&scaff);

> -	}

> +	if (context.len)

> +		security_release_secctx(&context);

>  	return NULL;

>  }

>  

> -- 

> 2.24.1

>
James Morris Nov. 10, 2020, 7:26 p.m. UTC | #2 
On Tue, 10 Nov 2020, Pablo Neira Ayuso wrote:

> Hi Casey,

> 

> On Wed, Nov 04, 2020 at 04:49:17PM -0800, Casey Schaufler wrote:

> > Change netlink netfilter interfaces to use lsmcontext

> > pointers, and remove scaffolding.

> > 

> > Reviewed-by: Kees Cook <keescook@chromium.org>

> > Reviewed-by: John Johansen <john.johansen@canonical.com>

> > Acked-by: Stephen Smalley <sds@tycho.nsa.gov>

> > Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>

> > Cc: netdev@vger.kernel.org

> > Cc: netfilter-devel@vger.kernel.org

> 

> You can carry this tag in your follow up patches.

> 

> Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>


Thanks for the review!

> 

> Thanks.

> 

> > ---

> >  net/netfilter/nfnetlink_queue.c | 37 +++++++++++++--------------------

> >  1 file changed, 14 insertions(+), 23 deletions(-)

> > 

> > diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c

> > index 84be5a49a157..0d8b83d84422 100644

> > --- a/net/netfilter/nfnetlink_queue.c

> > +++ b/net/netfilter/nfnetlink_queue.c

> > @@ -301,15 +301,13 @@ static int nfqnl_put_sk_uidgid(struct sk_buff *skb, struct sock *sk)

> >  	return -1;

> >  }

> >  

> > -static u32 nfqnl_get_sk_secctx(struct sk_buff *skb, char **secdata)

> > +static void nfqnl_get_sk_secctx(struct sk_buff *skb, struct lsmcontext *context)

> >  {

> > -	u32 seclen = 0;

> >  #if IS_ENABLED(CONFIG_NETWORK_SECMARK)

> >  	struct lsmblob blob;

> > -	struct lsmcontext context = { };

> >  

> >  	if (!skb || !sk_fullsock(skb->sk))

> > -		return 0;

> > +		return;

> >  

> >  	read_lock_bh(&skb->sk->sk_callback_lock);

> >  

> > @@ -318,14 +316,12 @@ static u32 nfqnl_get_sk_secctx(struct sk_buff *skb, char **secdata)

> >  		 * blob. security_secid_to_secctx() will know which security

> >  		 * module to use to create the secctx.  */

> >  		lsmblob_init(&blob, skb->secmark);

> > -		security_secid_to_secctx(&blob, &context);

> > -		*secdata = context.context;

> > +		security_secid_to_secctx(&blob, context);

> >  	}

> >  

> >  	read_unlock_bh(&skb->sk->sk_callback_lock);

> > -	seclen = context.len;

> >  #endif

> > -	return seclen;

> > +	return;

> >  }

> >  

> >  static u32 nfqnl_get_bridge_size(struct nf_queue_entry *entry)

> > @@ -398,12 +394,10 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,

> >  	struct net_device *indev;

> >  	struct net_device *outdev;

> >  	struct nf_conn *ct = NULL;

> > +	struct lsmcontext context = { };

> >  	enum ip_conntrack_info ctinfo;

> >  	struct nfnl_ct_hook *nfnl_ct;

> >  	bool csum_verify;

> > -	struct lsmcontext scaff; /* scaffolding */

> > -	char *secdata = NULL;

> > -	u32 seclen = 0;

> >  

> >  	size = nlmsg_total_size(sizeof(struct nfgenmsg))

> >  		+ nla_total_size(sizeof(struct nfqnl_msg_packet_hdr))

> > @@ -469,9 +463,9 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,

> >  	}

> >  

> >  	if ((queue->flags & NFQA_CFG_F_SECCTX) && entskb->sk) {

> > -		seclen = nfqnl_get_sk_secctx(entskb, &secdata);

> > -		if (seclen)

> > -			size += nla_total_size(seclen);

> > +		nfqnl_get_sk_secctx(entskb, &context);

> > +		if (context.len)

> > +			size += nla_total_size(context.len);

> >  	}

> >  

> >  	skb = alloc_skb(size, GFP_ATOMIC);

> > @@ -604,7 +598,8 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,

> >  	    nfqnl_put_sk_uidgid(skb, entskb->sk) < 0)

> >  		goto nla_put_failure;

> >  

> > -	if (seclen && nla_put(skb, NFQA_SECCTX, seclen, secdata))

> > +	if (context.len &&

> > +	    nla_put(skb, NFQA_SECCTX, context.len, context.context))

> >  		goto nla_put_failure;

> >  

> >  	if (ct && nfnl_ct->build(skb, ct, ctinfo, NFQA_CT, NFQA_CT_INFO) < 0)

> > @@ -632,10 +627,8 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,

> >  	}

> >  

> >  	nlh->nlmsg_len = skb->len;

> > -	if (seclen) {

> > -		lsmcontext_init(&scaff, secdata, seclen, 0);

> > -		security_release_secctx(&scaff);

> > -	}

> > +	if (context.len)

> > +		security_release_secctx(&context);

> >  	return skb;

> >  

> >  nla_put_failure:

> > @@ -643,10 +636,8 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,

> >  	kfree_skb(skb);

> >  	net_err_ratelimited("nf_queue: error creating packet message\n");

> >  nlmsg_failure:

> > -	if (seclen) {

> > -		lsmcontext_init(&scaff, secdata, seclen, 0);

> > -		security_release_secctx(&scaff);

> > -	}

> > +	if (context.len)

> > +		security_release_secctx(&context);

> >  	return NULL;

> >  }

> >  

> > -- 

> > 2.24.1

> > 

> 


-- 
James Morris
<jmorris@namei.org>
diff mbox series

Patch

diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c
index 84be5a49a157..0d8b83d84422 100644
--- a/net/netfilter/nfnetlink_queue.c
+++ b/net/netfilter/nfnetlink_queue.c
@@ -301,15 +301,13 @@  static int nfqnl_put_sk_uidgid(struct sk_buff *skb, struct sock *sk)
 	return -1;
 }
 
-static u32 nfqnl_get_sk_secctx(struct sk_buff *skb, char **secdata)
+static void nfqnl_get_sk_secctx(struct sk_buff *skb, struct lsmcontext *context)
 {
-	u32 seclen = 0;
 #if IS_ENABLED(CONFIG_NETWORK_SECMARK)
 	struct lsmblob blob;
-	struct lsmcontext context = { };
 
 	if (!skb || !sk_fullsock(skb->sk))
-		return 0;
+		return;
 
 	read_lock_bh(&skb->sk->sk_callback_lock);
 
@@ -318,14 +316,12 @@  static u32 nfqnl_get_sk_secctx(struct sk_buff *skb, char **secdata)
 		 * blob. security_secid_to_secctx() will know which security
 		 * module to use to create the secctx.  */
 		lsmblob_init(&blob, skb->secmark);
-		security_secid_to_secctx(&blob, &context);
-		*secdata = context.context;
+		security_secid_to_secctx(&blob, context);
 	}
 
 	read_unlock_bh(&skb->sk->sk_callback_lock);
-	seclen = context.len;
 #endif
-	return seclen;
+	return;
 }
 
 static u32 nfqnl_get_bridge_size(struct nf_queue_entry *entry)
@@ -398,12 +394,10 @@  nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
 	struct net_device *indev;
 	struct net_device *outdev;
 	struct nf_conn *ct = NULL;
+	struct lsmcontext context = { };
 	enum ip_conntrack_info ctinfo;
 	struct nfnl_ct_hook *nfnl_ct;
 	bool csum_verify;
-	struct lsmcontext scaff; /* scaffolding */
-	char *secdata = NULL;
-	u32 seclen = 0;
 
 	size = nlmsg_total_size(sizeof(struct nfgenmsg))
 		+ nla_total_size(sizeof(struct nfqnl_msg_packet_hdr))
@@ -469,9 +463,9 @@  nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
 	}
 
 	if ((queue->flags & NFQA_CFG_F_SECCTX) && entskb->sk) {
-		seclen = nfqnl_get_sk_secctx(entskb, &secdata);
-		if (seclen)
-			size += nla_total_size(seclen);
+		nfqnl_get_sk_secctx(entskb, &context);
+		if (context.len)
+			size += nla_total_size(context.len);
 	}
 
 	skb = alloc_skb(size, GFP_ATOMIC);
@@ -604,7 +598,8 @@  nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
 	    nfqnl_put_sk_uidgid(skb, entskb->sk) < 0)
 		goto nla_put_failure;
 
-	if (seclen && nla_put(skb, NFQA_SECCTX, seclen, secdata))
+	if (context.len &&
+	    nla_put(skb, NFQA_SECCTX, context.len, context.context))
 		goto nla_put_failure;
 
 	if (ct && nfnl_ct->build(skb, ct, ctinfo, NFQA_CT, NFQA_CT_INFO) < 0)
@@ -632,10 +627,8 @@  nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
 	}
 
 	nlh->nlmsg_len = skb->len;
-	if (seclen) {
-		lsmcontext_init(&scaff, secdata, seclen, 0);
-		security_release_secctx(&scaff);
-	}
+	if (context.len)
+		security_release_secctx(&context);
 	return skb;
 
 nla_put_failure:
@@ -643,10 +636,8 @@  nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
 	kfree_skb(skb);
 	net_err_ratelimited("nf_queue: error creating packet message\n");
 nlmsg_failure:
-	if (seclen) {
-		lsmcontext_init(&scaff, secdata, seclen, 0);
-		security_release_secctx(&scaff);
-	}
+	if (context.len)
+		security_release_secctx(&context);
 	return NULL;
 }