[PATCH] SELinux: Add sockcreate node to procattr API

Below is a patch to add a new /proc/self/attr/sockcreate A process may write a
context into this interface and all subsequent sockets created will be labeled
with that context.  This is the same idea as the fscreate interface where a
process can specify the label of a file about to be created.  At this time one
envisioned user of this will be xinetd.  It will be able to better label
sockets for the actual services.  At this time all sockets take the label of
the creating process, so all xinitd sockets would just be labeled the same.

I tested this by creating a tcp sender and listener.  The sender was able to
write to this new proc file and then create sockets with the specified label.
I am able to be sure the new label was used since the avc denial messages
kicked out by the kernel included both the new security permission
setsockcreate and all the socket denials were for the new label, not the label
of the running process.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Cc: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

3 files changed, 3 insertions, 0 deletions

diff --git a/security/selinux/include/av_perm_to_string.h b/security/selinux/include/av_perm_to_string.h
index e777578ccd9d..7c9b58380833 100644
--- a/security/selinux/include/av_perm_to_string.h
+++ b/security/selinux/include/av_perm_to_string.h
@@ -73,6 +73,7 @@
    S_(SECCLASS_PROCESS, PROCESS__EXECSTACK, "execstack")
    S_(SECCLASS_PROCESS, PROCESS__EXECHEAP, "execheap")
    S_(SECCLASS_PROCESS, PROCESS__SETKEYCREATE, "setkeycreate")
+   S_(SECCLASS_PROCESS, PROCESS__SETSOCKCREATE, "setsockcreate")
    S_(SECCLASS_MSGQ, MSGQ__ENQUEUE, "enqueue")
    S_(SECCLASS_MSG, MSG__SEND, "send")
    S_(SECCLASS_MSG, MSG__RECEIVE, "receive")
diff --git a/security/selinux/include/av_permissions.h b/security/selinux/include/av_permissions.h
index 1e1678023b68..69fd4b48202c 100644
--- a/security/selinux/include/av_permissions.h
+++ b/security/selinux/include/av_permissions.h
@@ -468,6 +468,7 @@
 #define PROCESS__EXECSTACK                        0x04000000UL
 #define PROCESS__EXECHEAP                         0x08000000UL
 #define PROCESS__SETKEYCREATE                     0x10000000UL
+#define PROCESS__SETSOCKCREATE                    0x20000000UL
 
 #define IPC__CREATE                               0x00000001UL
 #define IPC__DESTROY                              0x00000002UL
diff --git a/security/selinux/include/objsec.h b/security/selinux/include/objsec.h
index 191b3e4484ce..cf54a304169a 100644
--- a/security/selinux/include/objsec.h
+++ b/security/selinux/include/objsec.h
@@ -33,6 +33,7 @@ struct task_security_struct {
         u32 exec_sid;        /* exec SID */
         u32 create_sid;      /* fscreate SID */
         u32 keycreate_sid;   /* keycreate SID */
+        u32 sockcreate_sid;  /* fscreate SID */
         u32 ptrace_sid;      /* SID of ptrace parent */
 };