selinux: wrap global selinux state

Define a selinux state structure (struct selinux_state) for
global SELinux state and pass it explicitly to all security server
functions.  The public portion of the structure contains state
that is used throughout the SELinux code, such as the enforcing mode.
The structure also contains a pointer to a selinux_ss structure whose
definition is private to the security server and contains security
server specific state such as the policy database and SID table.

This change should have no effect on SELinux behavior or APIs
(userspace or LSM).  It merely wraps SELinux state and passes it
explicitly as needed.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
[PM: minor fixups needed due to collisions with the SCTP patches]
Signed-off-by: Paul Moore <paul@paul-moore.com>

1 files changed, 169 insertions, 59 deletions

diff --git a/security/selinux/include/security.h b/security/selinux/include/security.h
index 02f0412d42f2..c3a1ef10e710 100644
--- a/security/selinux/include/security.h
+++ b/security/selinux/include/security.h
@@ -13,6 +13,8 @@
 #include <linux/dcache.h>
 #include <linux/magic.h>
 #include <linux/types.h>
+#include <linux/refcount.h>
+#include <linux/workqueue.h>
 #include "flask.h"
 
 #define SECSID_NULL			0x00000000 /* unspecified SID */
@@ -81,13 +83,6 @@ enum {
 
 extern char *selinux_policycap_names[__POLICYDB_CAPABILITY_MAX];
 
-extern int selinux_policycap_netpeer;
-extern int selinux_policycap_openperm;
-extern int selinux_policycap_extsockclass;
-extern int selinux_policycap_alwaysnetwork;
-extern int selinux_policycap_cgroupseclabel;
-extern int selinux_policycap_nnp_nosuid_transition;
-
 /*
  * type_datum properties
  * available at the kernel policy version >= POLICYDB_VERSION_BOUNDARY
@@ -98,13 +93,95 @@ extern int selinux_policycap_nnp_nosuid_transition;
 /* limitation of boundary depth  */
 #define POLICYDB_BOUNDS_MAXDEPTH	4
 
-int security_mls_enabled(void);
+struct selinux_ss;
+
+struct selinux_state {
+	bool disabled;
+#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
+	bool enforcing;
+#endif
+	bool checkreqprot;
+	bool initialized;
+	bool policycap[__POLICYDB_CAPABILITY_MAX];
+	struct selinux_ss *ss;
+};
+
+void selinux_ss_init(struct selinux_ss **ss);
+
+extern struct selinux_state selinux_state;
+
+#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
+static inline bool is_enforcing(struct selinux_state *state)
+{
+	return state->enforcing;
+}
+
+static inline void set_enforcing(struct selinux_state *state, bool value)
+{
+	state->enforcing = value;
+}
+#else
+static inline bool is_enforcing(struct selinux_state *state)
+{
+	return true;
+}
+
+static inline void set_enforcing(struct selinux_state *state, bool value)
+{
+}
+#endif
+
+static inline bool selinux_policycap_netpeer(void)
+{
+	struct selinux_state *state = &selinux_state;
+
+	return state->policycap[POLICYDB_CAPABILITY_NETPEER];
+}
+
+static inline bool selinux_policycap_openperm(void)
+{
+	struct selinux_state *state = &selinux_state;
+
+	return state->policycap[POLICYDB_CAPABILITY_OPENPERM];
+}
 
-int security_load_policy(void *data, size_t len);
-int security_read_policy(void **data, size_t *len);
-size_t security_policydb_len(void);
+static inline bool selinux_policycap_extsockclass(void)
+{
+	struct selinux_state *state = &selinux_state;
+
+	return state->policycap[POLICYDB_CAPABILITY_EXTSOCKCLASS];
+}
 
-int security_policycap_supported(unsigned int req_cap);
+static inline bool selinux_policycap_alwaysnetwork(void)
+{
+	struct selinux_state *state = &selinux_state;
+
+	return state->policycap[POLICYDB_CAPABILITY_ALWAYSNETWORK];
+}
+
+static inline bool selinux_policycap_cgroupseclabel(void)
+{
+	struct selinux_state *state = &selinux_state;
+
+	return state->policycap[POLICYDB_CAPABILITY_CGROUPSECLABEL];
+}
+
+static inline bool selinux_policycap_nnp_nosuid_transition(void)
+{
+	struct selinux_state *state = &selinux_state;
+
+	return state->policycap[POLICYDB_CAPABILITY_NNP_NOSUID_TRANSITION];
+}
+
+int security_mls_enabled(struct selinux_state *state);
+int security_load_policy(struct selinux_state *state,
+			 void *data, size_t len);
+int security_read_policy(struct selinux_state *state,
+			 void **data, size_t *len);
+size_t security_policydb_len(struct selinux_state *state);
+
+int security_policycap_supported(struct selinux_state *state,
+				 unsigned int req_cap);
 
 #define SEL_VEC_MAX 32
 struct av_decision {
@@ -141,76 +218,100 @@ struct extended_perms {
 /* definitions of av_decision.flags */
 #define AVD_FLAGS_PERMISSIVE	0x0001
 
-void security_compute_av(u32 ssid, u32 tsid,
+void security_compute_av(struct selinux_state *state,
+			 u32 ssid, u32 tsid,
 			 u16 tclass, struct av_decision *avd,
 			 struct extended_perms *xperms);
 
-void security_compute_xperms_decision(u32 ssid, u32 tsid, u16 tclass,
-			 u8 driver, struct extended_perms_decision *xpermd);
+void security_compute_xperms_decision(struct selinux_state *state,
+				      u32 ssid, u32 tsid, u16 tclass,
+				      u8 driver,
+				      struct extended_perms_decision *xpermd);
 
-void security_compute_av_user(u32 ssid, u32 tsid,
-			     u16 tclass, struct av_decision *avd);
+void security_compute_av_user(struct selinux_state *state,
+			      u32 ssid, u32 tsid,
+			      u16 tclass, struct av_decision *avd);
 
-int security_transition_sid(u32 ssid, u32 tsid, u16 tclass,
+int security_transition_sid(struct selinux_state *state,
+			    u32 ssid, u32 tsid, u16 tclass,
 			    const struct qstr *qstr, u32 *out_sid);
 
-int security_transition_sid_user(u32 ssid, u32 tsid, u16 tclass,
+int security_transition_sid_user(struct selinux_state *state,
+				 u32 ssid, u32 tsid, u16 tclass,
 				 const char *objname, u32 *out_sid);
 
-int security_member_sid(u32 ssid, u32 tsid,
-	u16 tclass, u32 *out_sid);
+int security_member_sid(struct selinux_state *state, u32 ssid, u32 tsid,
+			u16 tclass, u32 *out_sid);
 
-int security_change_sid(u32 ssid, u32 tsid,
-	u16 tclass, u32 *out_sid);
+int security_change_sid(struct selinux_state *state, u32 ssid, u32 tsid,
+			u16 tclass, u32 *out_sid);
 
-int security_sid_to_context(u32 sid, char **scontext,
-	u32 *scontext_len);
+int security_sid_to_context(struct selinux_state *state, u32 sid,
+			    char **scontext, u32 *scontext_len);
 
-int security_sid_to_context_force(u32 sid, char **scontext, u32 *scontext_len);
+int security_sid_to_context_force(struct selinux_state *state,
+				  u32 sid, char **scontext, u32 *scontext_len);
 
-int security_context_to_sid(const char *scontext, u32 scontext_len,
+int security_context_to_sid(struct selinux_state *state,
+			    const char *scontext, u32 scontext_len,
 			    u32 *out_sid, gfp_t gfp);
 
-int security_context_str_to_sid(const char *scontext, u32 *out_sid, gfp_t gfp);
+int security_context_str_to_sid(struct selinux_state *state,
+				const char *scontext, u32 *out_sid, gfp_t gfp);
 
-int security_context_to_sid_default(const char *scontext, u32 scontext_len,
+int security_context_to_sid_default(struct selinux_state *state,
+				    const char *scontext, u32 scontext_len,
 				    u32 *out_sid, u32 def_sid, gfp_t gfp_flags);
 
-int security_context_to_sid_force(const char *scontext, u32 scontext_len,
+int security_context_to_sid_force(struct selinux_state *state,
+				  const char *scontext, u32 scontext_len,
 				  u32 *sid);
 
-int security_get_user_sids(u32 callsid, char *username,
+int security_get_user_sids(struct selinux_state *state,
+			   u32 callsid, char *username,
 			   u32 **sids, u32 *nel);
 
-int security_port_sid(u8 protocol, u16 port, u32 *out_sid);
+int security_port_sid(struct selinux_state *state,
+		      u8 protocol, u16 port, u32 *out_sid);
 
-int security_ib_pkey_sid(u64 subnet_prefix, u16 pkey_num, u32 *out_sid);
+int security_ib_pkey_sid(struct selinux_state *state,
+			 u64 subnet_prefix, u16 pkey_num, u32 *out_sid);
 
-int security_ib_endport_sid(const char *dev_name, u8 port_num, u32 *out_sid);
+int security_ib_endport_sid(struct selinux_state *state,
+			    const char *dev_name, u8 port_num, u32 *out_sid);
 
-int security_netif_sid(char *name, u32 *if_sid);
+int security_netif_sid(struct selinux_state *state,
+		       char *name, u32 *if_sid);
 
-int security_node_sid(u16 domain, void *addr, u32 addrlen,
-	u32 *out_sid);
+int security_node_sid(struct selinux_state *state,
+		      u16 domain, void *addr, u32 addrlen,
+		      u32 *out_sid);
 
-int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid,
+int security_validate_transition(struct selinux_state *state,
+				 u32 oldsid, u32 newsid, u32 tasksid,
 				 u16 tclass);
 
-int security_validate_transition_user(u32 oldsid, u32 newsid, u32 tasksid,
+int security_validate_transition_user(struct selinux_state *state,
+				      u32 oldsid, u32 newsid, u32 tasksid,
 				      u16 tclass);
 
-int security_bounded_transition(u32 oldsid, u32 newsid);
+int security_bounded_transition(struct selinux_state *state,
+				u32 oldsid, u32 newsid);
 
-int security_sid_mls_copy(u32 sid, u32 mls_sid, u32 *new_sid);
+int security_sid_mls_copy(struct selinux_state *state,
+			  u32 sid, u32 mls_sid, u32 *new_sid);
 
-int security_net_peersid_resolve(u32 nlbl_sid, u32 nlbl_type,
+int security_net_peersid_resolve(struct selinux_state *state,
+				 u32 nlbl_sid, u32 nlbl_type,
 				 u32 xfrm_sid,
 				 u32 *peer_sid);
 
-int security_get_classes(char ***classes, int *nclasses);
-int security_get_permissions(char *class, char ***perms, int *nperms);
-int security_get_reject_unknown(void);
-int security_get_allow_unknown(void);
+int security_get_classes(struct selinux_state *state,
+			 char ***classes, int *nclasses);
+int security_get_permissions(struct selinux_state *state,
+			     char *class, char ***perms, int *nperms);
+int security_get_reject_unknown(struct selinux_state *state);
+int security_get_allow_unknown(struct selinux_state *state);
 
 #define SECURITY_FS_USE_XATTR		1 /* use xattr */
 #define SECURITY_FS_USE_TRANS		2 /* use transition SIDs, e.g. devpts/tmpfs */
@@ -221,27 +322,31 @@ int security_get_allow_unknown(void);
 #define SECURITY_FS_USE_NATIVE		7 /* use native label support */
 #define SECURITY_FS_USE_MAX		7 /* Highest SECURITY_FS_USE_XXX */
 
-int security_fs_use(struct super_block *sb);
+int security_fs_use(struct selinux_state *state, struct super_block *sb);
 
-int security_genfs_sid(const char *fstype, char *name, u16 sclass,
-	u32 *sid);
+int security_genfs_sid(struct selinux_state *state,
+		       const char *fstype, char *name, u16 sclass,
+		       u32 *sid);
 
 #ifdef CONFIG_NETLABEL
-int security_netlbl_secattr_to_sid(struct netlbl_lsm_secattr *secattr,
+int security_netlbl_secattr_to_sid(struct selinux_state *state,
+				   struct netlbl_lsm_secattr *secattr,
 				   u32 *sid);
 
-int security_netlbl_sid_to_secattr(u32 sid,
+int security_netlbl_sid_to_secattr(struct selinux_state *state,
+				   u32 sid,
 				   struct netlbl_lsm_secattr *secattr);
 #else
-static inline int security_netlbl_secattr_to_sid(
+static inline int security_netlbl_secattr_to_sid(struct selinux_state *state,
 					    struct netlbl_lsm_secattr *secattr,
 					    u32 *sid)
 {
 	return -EIDRM;
 }
 
-static inline int security_netlbl_sid_to_secattr(u32 sid,
-					   struct netlbl_lsm_secattr *secattr)
+static inline int security_netlbl_sid_to_secattr(struct selinux_state *state,
+					 u32 sid,
+					 struct netlbl_lsm_secattr *secattr)
 {
 	return -ENOENT;
 }
@@ -252,7 +357,7 @@ const char *security_get_initial_sid_context(u32 sid);
 /*
  * status notifier using mmap interface
  */
-extern struct page *selinux_kernel_status_page(void);
+extern struct page *selinux_kernel_status_page(struct selinux_state *state);
 
 #define SELINUX_KERNEL_STATUS_VERSION	1
 struct selinux_kernel_status {
@@ -266,10 +371,12 @@ struct selinux_kernel_status {
 	 */
 } __packed;
 
-extern void selinux_status_update_setenforce(int enforcing);
-extern void selinux_status_update_policyload(int seqno);
+extern void selinux_status_update_setenforce(struct selinux_state *state,
+					     int enforcing);
+extern void selinux_status_update_policyload(struct selinux_state *state,
+					     int seqno);
 extern void selinux_complete_init(void);
-extern int selinux_disable(void);
+extern int selinux_disable(struct selinux_state *state);
 extern void exit_sel_fs(void);
 extern struct path selinux_null;
 extern struct vfsmount *selinuxfs_mount;
@@ -277,5 +384,8 @@ extern void selnl_notify_setenforce(int val);
 extern void selnl_notify_policyload(u32 seqno);
 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
 
-#endif /* _SELINUX_SECURITY_H_ */
+extern void avtab_cache_init(void);
+extern void ebitmap_cache_init(void);
+extern void hashtab_cache_init(void);
 
+#endif /* _SELINUX_SECURITY_H_ */