SELinux: create new open permission

Adds a new open permission inside SELinux when 'opening' a file.  The idea
is that opening a file and reading/writing to that file are not the same
thing.  Its different if a program had its stdout redirected to /tmp/output
than if the program tried to directly open /tmp/output. This should allow
policy writers to more liberally give read/write permissions across the
policy while still blocking many design and programing flaws SELinux is so
good at catching today.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Reviewed-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>

3 files changed, 12 insertions, 0 deletions

diff --git a/security/selinux/include/av_perm_to_string.h b/security/selinux/include/av_perm_to_string.h
index d5696690d3a2..1223b4ff9bee 100644
--- a/security/selinux/include/av_perm_to_string.h
+++ b/security/selinux/include/av_perm_to_string.h
@@ -14,12 +14,17 @@
    S_(SECCLASS_DIR, DIR__REPARENT, "reparent")
    S_(SECCLASS_DIR, DIR__SEARCH, "search")
    S_(SECCLASS_DIR, DIR__RMDIR, "rmdir")
+   S_(SECCLASS_DIR, DIR__OPEN, "open")
    S_(SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, "execute_no_trans")
    S_(SECCLASS_FILE, FILE__ENTRYPOINT, "entrypoint")
    S_(SECCLASS_FILE, FILE__EXECMOD, "execmod")
+   S_(SECCLASS_FILE, FILE__OPEN, "open")
    S_(SECCLASS_CHR_FILE, CHR_FILE__EXECUTE_NO_TRANS, "execute_no_trans")
    S_(SECCLASS_CHR_FILE, CHR_FILE__ENTRYPOINT, "entrypoint")
    S_(SECCLASS_CHR_FILE, CHR_FILE__EXECMOD, "execmod")
+   S_(SECCLASS_CHR_FILE, CHR_FILE__OPEN, "open")
+   S_(SECCLASS_BLK_FILE, BLK_FILE__OPEN, "open")
+   S_(SECCLASS_FIFO_FILE, FIFO_FILE__OPEN, "open")
    S_(SECCLASS_FD, FD__USE, "use")
    S_(SECCLASS_TCP_SOCKET, TCP_SOCKET__CONNECTTO, "connectto")
    S_(SECCLASS_TCP_SOCKET, TCP_SOCKET__NEWCONN, "newconn")
diff --git a/security/selinux/include/av_permissions.h b/security/selinux/include/av_permissions.h
index 75b41311ab86..c4c51165c505 100644
--- a/security/selinux/include/av_permissions.h
+++ b/security/selinux/include/av_permissions.h
@@ -79,6 +79,7 @@
 #define DIR__REPARENT                             0x00080000UL
 #define DIR__SEARCH                               0x00100000UL
 #define DIR__RMDIR                                0x00200000UL
+#define DIR__OPEN                                 0x00400000UL
 #define FILE__IOCTL                               0x00000001UL
 #define FILE__READ                                0x00000002UL
 #define FILE__WRITE                               0x00000004UL
@@ -99,6 +100,7 @@
 #define FILE__EXECUTE_NO_TRANS                    0x00020000UL
 #define FILE__ENTRYPOINT                          0x00040000UL
 #define FILE__EXECMOD                             0x00080000UL
+#define FILE__OPEN                                0x00100000UL
 #define LNK_FILE__IOCTL                           0x00000001UL
 #define LNK_FILE__READ                            0x00000002UL
 #define LNK_FILE__WRITE                           0x00000004UL
@@ -136,6 +138,7 @@
 #define CHR_FILE__EXECUTE_NO_TRANS                0x00020000UL
 #define CHR_FILE__ENTRYPOINT                      0x00040000UL
 #define CHR_FILE__EXECMOD                         0x00080000UL
+#define CHR_FILE__OPEN                            0x00100000UL
 #define BLK_FILE__IOCTL                           0x00000001UL
 #define BLK_FILE__READ                            0x00000002UL
 #define BLK_FILE__WRITE                           0x00000004UL
@@ -153,6 +156,7 @@
 #define BLK_FILE__SWAPON                          0x00004000UL
 #define BLK_FILE__QUOTAON                         0x00008000UL
 #define BLK_FILE__MOUNTON                         0x00010000UL
+#define BLK_FILE__OPEN                            0x00020000UL
 #define SOCK_FILE__IOCTL                          0x00000001UL
 #define SOCK_FILE__READ                           0x00000002UL
 #define SOCK_FILE__WRITE                          0x00000004UL
@@ -187,6 +191,7 @@
 #define FIFO_FILE__SWAPON                         0x00004000UL
 #define FIFO_FILE__QUOTAON                        0x00008000UL
 #define FIFO_FILE__MOUNTON                        0x00010000UL
+#define FIFO_FILE__OPEN                           0x00020000UL
 #define FD__USE                                   0x00000001UL
 #define SOCKET__IOCTL                             0x00000001UL
 #define SOCKET__READ                              0x00000002UL
diff --git a/security/selinux/include/security.h b/security/selinux/include/security.h
index 44e12ec88090..315b4ec1e12a 100644
--- a/security/selinux/include/security.h
+++ b/security/selinux/include/security.h
@@ -48,11 +48,13 @@ extern int selinux_mls_enabled;
 /* Policy capabilities */
 enum {
         POLICYDB_CAPABILITY_NETPEER,
+        POLICYDB_CAPABILITY_OPENPERM,
         __POLICYDB_CAPABILITY_MAX
 };
 #define POLICYDB_CAPABILITY_MAX (__POLICYDB_CAPABILITY_MAX - 1)
 
 extern int selinux_policycap_netpeer;
+extern int selinux_policycap_openperm;
 
 int security_load_policy(void * data, size_t len);