[v11,05/25] net: Prepare UDS for security module stacking
diff mbox series

Message ID 20191113181925.2437-6-casey@schaufler-ca.com
State New
Headers show
Series
  • [v11,01/25] LSM: Infrastructure management of the sock security
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Commit Message

Casey Schaufler Nov. 13, 2019, 6:19 p.m. UTC
Change the data used in UDS SO_PEERSEC processing from a
secid to a more general struct lsmblob. Update the
security_socket_getpeersec_dgram() interface to use the
lsmblob. There is a small amount of scaffolding code
that will come out when the security_secid_to_secctx()
code is brought in line with the lsmblob.

Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
cc: netdev@vger.kernel.org
---
 include/linux/security.h |  7 +++++--
 include/net/af_unix.h    |  2 +-
 include/net/scm.h        |  8 +++++---
 net/ipv4/ip_sockglue.c   |  8 +++++---
 net/unix/af_unix.c       |  6 +++---
 security/security.c      | 18 +++++++++++++++---
 6 files changed, 34 insertions(+), 15 deletions(-)

Comments

John Johansen Nov. 21, 2019, 6:41 p.m. UTC | #1
On 11/13/19 10:19 AM, Casey Schaufler wrote:
> Change the data used in UDS SO_PEERSEC processing from a
> secid to a more general struct lsmblob. Update the
> security_socket_getpeersec_dgram() interface to use the
> lsmblob. There is a small amount of scaffolding code
> that will come out when the security_secid_to_secctx()
> code is brought in line with the lsmblob.
> 
> Reviewed-by: Kees Cook <keescook@chromium.org>
> Reviewed-by: John Johansen <john.johansen@canonical.com>
> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
> cc: netdev@vger.kernel.org

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



> ---
>  include/linux/security.h |  7 +++++--
>  include/net/af_unix.h    |  2 +-
>  include/net/scm.h        |  8 +++++---
>  net/ipv4/ip_sockglue.c   |  8 +++++---
>  net/unix/af_unix.c       |  6 +++---
>  security/security.c      | 18 +++++++++++++++---
>  6 files changed, 34 insertions(+), 15 deletions(-)
> 
> diff --git a/include/linux/security.h b/include/linux/security.h
> index 2b0ab47cfb26..d57f400a307e 100644
> --- a/include/linux/security.h
> +++ b/include/linux/security.h
> @@ -1354,7 +1354,8 @@ int security_socket_shutdown(struct socket *sock, int how);
>  int security_sock_rcv_skb(struct sock *sk, struct sk_buff *skb);
>  int security_socket_getpeersec_stream(struct socket *sock, char __user *optval,
>  				      int __user *optlen, unsigned len);
> -int security_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid);
> +int security_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb,
> +				     struct lsmblob *blob);
>  int security_sk_alloc(struct sock *sk, int family, gfp_t priority);
>  void security_sk_free(struct sock *sk);
>  void security_sk_clone(const struct sock *sk, struct sock *newsk);
> @@ -1492,7 +1493,9 @@ static inline int security_socket_getpeersec_stream(struct socket *sock, char __
>  	return -ENOPROTOOPT;
>  }
>  
> -static inline int security_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
> +static inline int security_socket_getpeersec_dgram(struct socket *sock,
> +						   struct sk_buff *skb,
> +						   struct lsmblob *blob)
>  {
>  	return -ENOPROTOOPT;
>  }
> diff --git a/include/net/af_unix.h b/include/net/af_unix.h
> index 3426d6dacc45..933492c08b8c 100644
> --- a/include/net/af_unix.h
> +++ b/include/net/af_unix.h
> @@ -36,7 +36,7 @@ struct unix_skb_parms {
>  	kgid_t			gid;
>  	struct scm_fp_list	*fp;		/* Passed files		*/
>  #ifdef CONFIG_SECURITY_NETWORK
> -	u32			secid;		/* Security ID		*/
> +	struct lsmblob		lsmblob;	/* Security LSM data	*/
>  #endif
>  	u32			consumed;
>  } __randomize_layout;
> diff --git a/include/net/scm.h b/include/net/scm.h
> index 1ce365f4c256..e2e71c4bf9d0 100644
> --- a/include/net/scm.h
> +++ b/include/net/scm.h
> @@ -33,7 +33,7 @@ struct scm_cookie {
>  	struct scm_fp_list	*fp;		/* Passed files		*/
>  	struct scm_creds	creds;		/* Skb credentials	*/
>  #ifdef CONFIG_SECURITY_NETWORK
> -	u32			secid;		/* Passed security ID 	*/
> +	struct lsmblob		lsmblob;	/* Passed LSM data	*/
>  #endif
>  };
>  
> @@ -46,7 +46,7 @@ struct scm_fp_list *scm_fp_dup(struct scm_fp_list *fpl);
>  #ifdef CONFIG_SECURITY_NETWORK
>  static __inline__ void unix_get_peersec_dgram(struct socket *sock, struct scm_cookie *scm)
>  {
> -	security_socket_getpeersec_dgram(sock, NULL, &scm->secid);
> +	security_socket_getpeersec_dgram(sock, NULL, &scm->lsmblob);
>  }
>  #else
>  static __inline__ void unix_get_peersec_dgram(struct socket *sock, struct scm_cookie *scm)
> @@ -97,7 +97,9 @@ static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct sc
>  	int err;
>  
>  	if (test_bit(SOCK_PASSSEC, &sock->flags)) {
> -		err = security_secid_to_secctx(scm->secid, &secdata, &seclen);
> +		/* Scaffolding - it has to be element 0 for now */
> +		err = security_secid_to_secctx(scm->lsmblob.secid[0],
> +					       &secdata, &seclen);
>  
>  		if (!err) {
>  			put_cmsg(msg, SOL_SOCKET, SCM_SECURITY, seclen, secdata);
> diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
> index aa3fd61818c4..6cf57d5ac899 100644
> --- a/net/ipv4/ip_sockglue.c
> +++ b/net/ipv4/ip_sockglue.c
> @@ -130,15 +130,17 @@ static void ip_cmsg_recv_checksum(struct msghdr *msg, struct sk_buff *skb,
>  
>  static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb)
>  {
> +	struct lsmblob lb;
>  	char *secdata;
> -	u32 seclen, secid;
> +	u32 seclen;
>  	int err;
>  
> -	err = security_socket_getpeersec_dgram(NULL, skb, &secid);
> +	err = security_socket_getpeersec_dgram(NULL, skb, &lb);
>  	if (err)
>  		return;
>  
> -	err = security_secid_to_secctx(secid, &secdata, &seclen);
> +	/* Scaffolding - it has to be element 0 */
> +	err = security_secid_to_secctx(lb.secid[0], &secdata, &seclen);
>  	if (err)
>  		return;
>  
> diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
> index 0d8da809bea2..189fd6644e7f 100644
> --- a/net/unix/af_unix.c
> +++ b/net/unix/af_unix.c
> @@ -138,17 +138,17 @@ static struct hlist_head *unix_sockets_unbound(void *addr)
>  #ifdef CONFIG_SECURITY_NETWORK
>  static void unix_get_secdata(struct scm_cookie *scm, struct sk_buff *skb)
>  {
> -	UNIXCB(skb).secid = scm->secid;
> +	UNIXCB(skb).lsmblob = scm->lsmblob;
>  }
>  
>  static inline void unix_set_secdata(struct scm_cookie *scm, struct sk_buff *skb)
>  {
> -	scm->secid = UNIXCB(skb).secid;
> +	scm->lsmblob = UNIXCB(skb).lsmblob;
>  }
>  
>  static inline bool unix_secdata_eq(struct scm_cookie *scm, struct sk_buff *skb)
>  {
> -	return (scm->secid == UNIXCB(skb).secid);
> +	return lsmblob_equal(&scm->lsmblob, &(UNIXCB(skb).lsmblob));
>  }
>  #else
>  static inline void unix_get_secdata(struct scm_cookie *scm, struct sk_buff *skb)
> diff --git a/security/security.c b/security/security.c
> index dd6f212e11af..55837706e3ef 100644
> --- a/security/security.c
> +++ b/security/security.c
> @@ -2108,10 +2108,22 @@ int security_socket_getpeersec_stream(struct socket *sock, char __user *optval,
>  				optval, optlen, len);
>  }
>  
> -int security_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
> +int security_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb,
> +				     struct lsmblob *blob)
>  {
> -	return call_int_hook(socket_getpeersec_dgram, -ENOPROTOOPT, sock,
> -			     skb, secid);
> +	struct security_hook_list *hp;
> +	int rc = -ENOPROTOOPT;
> +
> +	hlist_for_each_entry(hp, &security_hook_heads.socket_getpeersec_dgram,
> +			     list) {
> +		if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
> +			continue;
> +		rc = hp->hook.socket_getpeersec_dgram(sock, skb,
> +						&blob->secid[hp->lsmid->slot]);
> +		if (rc != 0)
> +			break;
> +	}
> +	return rc;
>  }
>  EXPORT_SYMBOL(security_socket_getpeersec_dgram);
>  
>

Patch
diff mbox series

diff --git a/include/linux/security.h b/include/linux/security.h
index 2b0ab47cfb26..d57f400a307e 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -1354,7 +1354,8 @@  int security_socket_shutdown(struct socket *sock, int how);
 int security_sock_rcv_skb(struct sock *sk, struct sk_buff *skb);
 int security_socket_getpeersec_stream(struct socket *sock, char __user *optval,
 				      int __user *optlen, unsigned len);
-int security_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid);
+int security_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb,
+				     struct lsmblob *blob);
 int security_sk_alloc(struct sock *sk, int family, gfp_t priority);
 void security_sk_free(struct sock *sk);
 void security_sk_clone(const struct sock *sk, struct sock *newsk);
@@ -1492,7 +1493,9 @@  static inline int security_socket_getpeersec_stream(struct socket *sock, char __
 	return -ENOPROTOOPT;
 }
 
-static inline int security_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
+static inline int security_socket_getpeersec_dgram(struct socket *sock,
+						   struct sk_buff *skb,
+						   struct lsmblob *blob)
 {
 	return -ENOPROTOOPT;
 }
diff --git a/include/net/af_unix.h b/include/net/af_unix.h
index 3426d6dacc45..933492c08b8c 100644
--- a/include/net/af_unix.h
+++ b/include/net/af_unix.h
@@ -36,7 +36,7 @@  struct unix_skb_parms {
 	kgid_t			gid;
 	struct scm_fp_list	*fp;		/* Passed files		*/
 #ifdef CONFIG_SECURITY_NETWORK
-	u32			secid;		/* Security ID		*/
+	struct lsmblob		lsmblob;	/* Security LSM data	*/
 #endif
 	u32			consumed;
 } __randomize_layout;
diff --git a/include/net/scm.h b/include/net/scm.h
index 1ce365f4c256..e2e71c4bf9d0 100644
--- a/include/net/scm.h
+++ b/include/net/scm.h
@@ -33,7 +33,7 @@  struct scm_cookie {
 	struct scm_fp_list	*fp;		/* Passed files		*/
 	struct scm_creds	creds;		/* Skb credentials	*/
 #ifdef CONFIG_SECURITY_NETWORK
-	u32			secid;		/* Passed security ID 	*/
+	struct lsmblob		lsmblob;	/* Passed LSM data	*/
 #endif
 };
 
@@ -46,7 +46,7 @@  struct scm_fp_list *scm_fp_dup(struct scm_fp_list *fpl);
 #ifdef CONFIG_SECURITY_NETWORK
 static __inline__ void unix_get_peersec_dgram(struct socket *sock, struct scm_cookie *scm)
 {
-	security_socket_getpeersec_dgram(sock, NULL, &scm->secid);
+	security_socket_getpeersec_dgram(sock, NULL, &scm->lsmblob);
 }
 #else
 static __inline__ void unix_get_peersec_dgram(struct socket *sock, struct scm_cookie *scm)
@@ -97,7 +97,9 @@  static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct sc
 	int err;
 
 	if (test_bit(SOCK_PASSSEC, &sock->flags)) {
-		err = security_secid_to_secctx(scm->secid, &secdata, &seclen);
+		/* Scaffolding - it has to be element 0 for now */
+		err = security_secid_to_secctx(scm->lsmblob.secid[0],
+					       &secdata, &seclen);
 
 		if (!err) {
 			put_cmsg(msg, SOL_SOCKET, SCM_SECURITY, seclen, secdata);
diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index aa3fd61818c4..6cf57d5ac899 100644
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -130,15 +130,17 @@  static void ip_cmsg_recv_checksum(struct msghdr *msg, struct sk_buff *skb,
 
 static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb)
 {
+	struct lsmblob lb;
 	char *secdata;
-	u32 seclen, secid;
+	u32 seclen;
 	int err;
 
-	err = security_socket_getpeersec_dgram(NULL, skb, &secid);
+	err = security_socket_getpeersec_dgram(NULL, skb, &lb);
 	if (err)
 		return;
 
-	err = security_secid_to_secctx(secid, &secdata, &seclen);
+	/* Scaffolding - it has to be element 0 */
+	err = security_secid_to_secctx(lb.secid[0], &secdata, &seclen);
 	if (err)
 		return;
 
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 0d8da809bea2..189fd6644e7f 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -138,17 +138,17 @@  static struct hlist_head *unix_sockets_unbound(void *addr)
 #ifdef CONFIG_SECURITY_NETWORK
 static void unix_get_secdata(struct scm_cookie *scm, struct sk_buff *skb)
 {
-	UNIXCB(skb).secid = scm->secid;
+	UNIXCB(skb).lsmblob = scm->lsmblob;
 }
 
 static inline void unix_set_secdata(struct scm_cookie *scm, struct sk_buff *skb)
 {
-	scm->secid = UNIXCB(skb).secid;
+	scm->lsmblob = UNIXCB(skb).lsmblob;
 }
 
 static inline bool unix_secdata_eq(struct scm_cookie *scm, struct sk_buff *skb)
 {
-	return (scm->secid == UNIXCB(skb).secid);
+	return lsmblob_equal(&scm->lsmblob, &(UNIXCB(skb).lsmblob));
 }
 #else
 static inline void unix_get_secdata(struct scm_cookie *scm, struct sk_buff *skb)
diff --git a/security/security.c b/security/security.c
index dd6f212e11af..55837706e3ef 100644
--- a/security/security.c
+++ b/security/security.c
@@ -2108,10 +2108,22 @@  int security_socket_getpeersec_stream(struct socket *sock, char __user *optval,
 				optval, optlen, len);
 }
 
-int security_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
+int security_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb,
+				     struct lsmblob *blob)
 {
-	return call_int_hook(socket_getpeersec_dgram, -ENOPROTOOPT, sock,
-			     skb, secid);
+	struct security_hook_list *hp;
+	int rc = -ENOPROTOOPT;
+
+	hlist_for_each_entry(hp, &security_hook_heads.socket_getpeersec_dgram,
+			     list) {
+		if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
+			continue;
+		rc = hp->hook.socket_getpeersec_dgram(sock, skb,
+						&blob->secid[hp->lsmid->slot]);
+		if (rc != 0)
+			break;
+	}
+	return rc;
 }
 EXPORT_SYMBOL(security_socket_getpeersec_dgram);