[patch 20/51] selinux: Add new NetLabel glue code to handle labeling of connection requests

Greg KH
2009-05-14T22:48:59Z

[-- Attachment #1: selinux-add-new-netlabel-glue-code-to-handle-labeling-of-connection-requests.patch --]
[-- Type: text/plain, Size: 7317 bytes --]

2.6.29-stable review patch. If anyone has any objections, please let us know.

------------------

From: Paul Moore <paul.moore@hp.com>

[NOTE: based on 389fb800ac8be2832efedd19978a2b8ced37eb61]

This patch provides the missing functions to properly handle the labeling of
responses to incoming connection requests within SELinux.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

security/selinux/hooks.c | 4 -
security/selinux/include/netlabel.h | 17 +++--
security/selinux/netlabel.c | 118 ++++++++++++++++++------------------
3 files changed, 72 insertions(+), 67 deletions(-)

--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -3799,7 +3799,7 @@ static int selinux_socket_post_create(st
sksec = sock->sk->sk_security;
sksec->sid = isec->sid;
sksec->sclass = isec->sclass;
- err = selinux_netlbl_socket_post_create(sock);
+ err = selinux_netlbl_socket_post_create(sock->sk, family);
}

return err;
@@ -4467,8 +4467,6 @@ static void selinux_inet_conn_establishe
family = PF_INET;

selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
-
- selinux_netlbl_inet_conn_established(sk, family);
}

static void selinux_req_classify_flow(const struct request_sock *req,
--- a/security/selinux/include/netlabel.h
+++ b/security/selinux/include/netlabel.h
@@ -32,6 +32,7 @@
#include <linux/net.h>
#include <linux/skbuff.h>
#include <net/sock.h>
+#include <net/request_sock.h>

#include "avc.h"
#include "objsec.h"
@@ -53,8 +54,9 @@ int selinux_netlbl_skbuff_setsid(struct
u16 family,
u32 sid);

-void selinux_netlbl_inet_conn_established(struct sock *sk, u16 family);
-int selinux_netlbl_socket_post_create(struct socket *sock);
+int selinux_netlbl_inet_conn_request(struct request_sock *req, u16 family);
+void selinux_netlbl_inet_csk_clone(struct sock *sk, u16 family);
+int selinux_netlbl_socket_post_create(struct sock *sk, u16 family);
int selinux_netlbl_inode_permission(struct inode *inode, int mask);
int selinux_netlbl_sock_rcv_skb(struct sk_security_struct *sksec,
struct sk_buff *skb,
@@ -113,12 +115,17 @@ static inline int selinux_netlbl_conn_se
return 0;
}

-static inline void selinux_netlbl_inet_conn_established(struct sock *sk,
- u16 family)
+static inline int selinux_netlbl_inet_conn_request(struct request_sock *req,
+ u16 family)
+{
+ return 0;
+}
+static inline void selinux_netlbl_inet_csk_clone(struct sock *sk, u16 family)
{
return;
}
-static inline int selinux_netlbl_socket_post_create(struct socket *sock)
+static inline int selinux_netlbl_socket_post_create(struct sock *sk,
+ u16 family)
{
return 0;
}
--- a/security/selinux/netlabel.c
+++ b/security/selinux/netlabel.c
@@ -281,73 +281,52 @@ skbuff_setsid_return:
}

/**
- * selinux_netlbl_inet_conn_established - Netlabel the newly accepted connection
- * @sk: the new connection
+ * selinux_netlbl_inet_conn_request - Label an incoming stream connection
+ * @req: incoming connection request socket
*
* Description:
- * A new connection has been established on @sk so make sure it is labeled
- * correctly with the NetLabel susbsystem.
+ * A new incoming connection request is represented by @req, we need to label
+ * the new request_sock here and the stack will ensure the on-the-wire label
+ * will get preserved when a full sock is created once the connection handshake
+ * is complete. Returns zero on success, negative values on failure.
*
*/
-void selinux_netlbl_inet_conn_established(struct sock *sk, u16 family)
+int selinux_netlbl_inet_conn_request(struct request_sock *req, u16 family)
{
int rc;
- struct sk_security_struct *sksec = sk->sk_security;
- struct netlbl_lsm_secattr *secattr;
- struct inet_sock *sk_inet = inet_sk(sk);
- struct sockaddr_in addr;
+ struct netlbl_lsm_secattr secattr;

- if (sksec->nlbl_state != NLBL_REQUIRE)
- return;
+ if (family != PF_INET)
+ return 0;

- secattr = selinux_netlbl_sock_genattr(sk);
- if (secattr == NULL)
- return;
+ netlbl_secattr_init(&secattr);
+ rc = security_netlbl_sid_to_secattr(req->secid, &secattr);
+ if (rc != 0)
+ goto inet_conn_request_return;
+ rc = netlbl_req_setattr(req, &secattr);
+inet_conn_request_return:
+ netlbl_secattr_destroy(&secattr);
+ return rc;
+}

- rc = netlbl_sock_setattr(sk, secattr);
- switch (rc) {
- case 0:
+/**
+ * selinux_netlbl_inet_csk_clone - Initialize the newly created sock
+ * @sk: the new sock
+ *
+ * Description:
+ * A new connection has been established using @sk, we've already labeled the
+ * socket via the request_sock struct in selinux_netlbl_inet_conn_request() but
+ * we need to set the NetLabel state here since we now have a sock structure.
+ *
+ */
+void selinux_netlbl_inet_csk_clone(struct sock *sk, u16 family)
+{
+ struct sk_security_struct *sksec = sk->sk_security;
+
+ if (family == PF_INET)
sksec->nlbl_state = NLBL_LABELED;
- break;
- case -EDESTADDRREQ:
- /* no PF_INET6 support yet because we don't support any IPv6
- * labeling protocols */
- if (family != PF_INET) {
- sksec->nlbl_state = NLBL_UNSET;
- return;
- }
-
- addr.sin_family = family;
- addr.sin_addr.s_addr = sk_inet->daddr;
- if (netlbl_conn_setattr(sk, (struct sockaddr *)&addr,
- secattr) != 0) {
- /* we failed to label the connected socket (could be
- * for a variety of reasons, the actual "why" isn't
- * important here) so we have to go to our backup plan,
- * labeling the packets individually in the netfilter
- * local output hook. this is okay but we need to
- * adjust the MSS of the connection to take into
- * account any labeling overhead, since we don't know
- * the exact overhead at this point we'll use the worst
- * case value which is 40 bytes for IPv4 */
- struct inet_connection_sock *sk_conn = inet_csk(sk);
- sk_conn->icsk_ext_hdr_len += 40 -
- (sk_inet->opt ? sk_inet->opt->optlen : 0);
- sk_conn->icsk_sync_mss(sk, sk_conn->icsk_pmtu_cookie);
-
- sksec->nlbl_state = NLBL_REQSKB;
- } else
- sksec->nlbl_state = NLBL_CONNLABELED;
- break;
- default:
- /* note that we are failing to label the socket which could be
- * a bad thing since it means traffic could leave the system
- * without the desired labeling, however, all is not lost as
- * we have a check in selinux_netlbl_inode_permission() to
- * pick up the pieces that we might drop here because we can't
- * return an error code */
- break;
- }
+ else
+ sksec->nlbl_state = NLBL_UNSET;
}

/**
@@ -359,9 +338,30 @@ void selinux_netlbl_inet_conn_establishe
* SID. Returns zero values on success, negative values on failure.
*
*/
-int selinux_netlbl_socket_post_create(struct socket *sock)
+int selinux_netlbl_socket_post_create(struct sock *sk, u16 family)
{
- return selinux_netlbl_sock_setsid(sock->sk);
+ int rc;
+ struct sk_security_struct *sksec = sk->sk_security;
+ struct netlbl_lsm_secattr *secattr;
+
+ if (family != PF_INET)
+ return 0;
+
+ secattr = selinux_netlbl_sock_genattr(sk);
+ if (secattr == NULL)
+ return -ENOMEM;
+ rc = netlbl_sock_setattr(sk, secattr);
+ switch (rc) {
+ case 0:
+ sksec->nlbl_state = NLBL_LABELED;
+ break;
+ case -EDESTADDRREQ:
+ sksec->nlbl_state = NLBL_REQSKB;
+ rc = 0;
+ break;
+ }
+
+ return rc;
}

/**