Enrich
authorchunhan
Wed, 18 Dec 2013 10:44:36 +0800
changeset 78 030643fab8a1
parent 77 6f7b9039715f
child 79 c09fcbcdb871
Enrich
Flask.thy
no_shm_selinux/Enrich.thy
no_shm_selinux/Flask.thy
--- a/Flask.thy	Tue Dec 17 13:30:21 2013 +0800
+++ b/Flask.thy	Wed Dec 18 10:44:36 2013 +0800
@@ -1316,7 +1316,7 @@
        Some pf \<Rightarrow> 
          (case (sectxt_of_obj s (O_proc p), sectxt_of_obj s (O_dir pf)) of 
            (Some (pu,pr,pt), Some (du,dr,dt)) \<Rightarrow> 
-             (search_check s (pu,pr,pt) f \<and> 
+             (search_check s (pu,pr,pt) pf \<and> 
               permission_check (pu,pr,pt) (nfctxt_create (pu,pr,pt) (du,dr,dt) C_dir) C_dir P_create \<and>
               permission_check (pu,pr,pt) (du,dr,dt) C_dir P_add_name)
          | _ \<Rightarrow> False)
--- a/no_shm_selinux/Enrich.thy	Tue Dec 17 13:30:21 2013 +0800
+++ b/no_shm_selinux/Enrich.thy	Wed Dec 18 10:44:36 2013 +0800
@@ -3,6 +3,14 @@
  Temp
 begin
 
+datatype t_enrich_obj = 
+  E_proc "t_process"
+| E_file "t_file"
+| E_fd   "t_process" "t_fd"
+| E_inum "nat"
+| E_msgq "t_msgq"
+| E_msg  "t_msgq"    "t_msg"
+
 context tainting_s begin
 
 (* enrich s target_proc duplicated_pro *)
@@ -78,6 +86,44 @@
     by (case_tac a, simp)
 qed
 
+lemma enrich_search_check':
+  assumes grant: "search_check s (up, rp, tp) f"
+  and cf2sf: "\<forall> f. f \<in> current_files s \<longrightarrow> cf2sfile s' f = cf2sfile s f"
+  and vd: "valid s" and vd': "valid s'" and f_in: "is_dir s f"  and f_in': "is_dir s' f"
+  and sec: "sectxt_of_obj s' (O_dir f) = sectxt_of_obj s (O_dir f)"
+  shows "search_check s' (up, rp, tp) f"
+proof (cases f)
+  case Nil
+  have "sectxt_of_obj s' (O_dir []) = sectxt_of_obj s (O_dir [])"
+    using cf2sf 
+    apply (erule_tac x = "[]" in allE)
+    by (auto simp:cf2sfile_def root_sec_remains vd vd')
+  thus ?thesis using grant Nil 
+    by auto
+next
+  case (Cons n pf)
+  from vd f_in obtain sf where sf: "cf2sfile s f = Some sf"
+    apply (drule_tac is_dir_in_current, drule_tac current_file_has_sfile, simp)
+    apply (erule exE, simp)
+    done
+  then obtain psfs where psfs: "get_parentfs_ctxts s pf = Some psfs" using Cons
+    by (auto simp:cf2sfile_def split:option.splits if_splits)
+  from sf cf2sf f_in have sf': "cf2sfile s' f = Some sf" by (auto dest:is_dir_in_current)
+  then obtain psfs' where psfs': "get_parentfs_ctxts s' pf = Some psfs'"using Cons
+    by (auto simp:cf2sfile_def split:option.splits if_splits)
+  with sf sf' psfs have psfs_eq: "set psfs' = set psfs" using Cons f_in f_in'
+    apply (drule_tac is_dir_not_file)
+    apply (drule is_dir_not_file)    
+    apply (simp add:cf2sfile_def split:option.splits)
+    apply (case_tac sf, simp)
+    done
+  show ?thesis using grant f_in f_in' psfs psfs' psfs_eq sec
+    apply (drule_tac is_dir_not_file)
+    apply (drule_tac is_dir_not_file)
+    apply (simp add:Cons split:option.splits)
+    by (case_tac a, simp)
+qed
+
 lemma proc_filefd_has_sfd: "\<lbrakk>fd \<in> proc_file_fds s p; valid s\<rbrakk> \<Longrightarrow> \<exists> sfd. cfd2sfd s p fd = Some sfd"
 apply (simp add:proc_file_fds_def)
 apply (auto dest: current_filefd_has_sfd)
@@ -132,24 +178,34 @@
 apply (case_tac a, auto)
 done
 
-fun enrich_not_alive :: "t_state \<Rightarrow> t_object \<Rightarrow> bool"
+fun enrich_not_alive :: "t_state \<Rightarrow> t_enrich_obj \<Rightarrow> bool"
 where
-  "enrich_not_alive s (O_file f) = (f \<notin> current_files s)"
-| "enrich_not_alive s (O_dir  f) = (f \<notin> current_files s)"
-| "enrich_not_alive s (O_proc p) = (p \<notin> current_procs s)"
-| "enrich_not_alive s (O_fd p fd) = (fd \<notin> current_proc_fds s p)"
-| "enrich_not_alive s (O_msgq q) = (q \<notin> current_msgqs s)"
-| "enrich_not_alive s (O_msg q m) = (m \<notin> set (msgs_of_queue s q) \<or> q \<notin> current_msgqs s)"
-| "enrich_not_alive s _ = True"
+  "enrich_not_alive s (E_file f) = (f \<notin> current_files s)"
+| "enrich_not_alive s (E_proc p) = (p \<notin> current_procs s)"
+| "enrich_not_alive s (E_fd p fd) = (p \<in> current_procs s \<longrightarrow> fd \<notin> current_proc_fds s p)"
+| "enrich_not_alive s (E_msgq q) = (q \<notin> current_msgqs s)"
+| "enrich_not_alive s (E_inum i) = (i \<notin> current_inode_nums s)"
+| "enrich_not_alive s (E_msg q m) = (q \<in> current_msgqs s \<longrightarrow> m \<notin> set (msgs_of_queue s q))"
+
+lemma file_has_parent: "\<lbrakk>is_file s f; valid s\<rbrakk> \<Longrightarrow> \<exists> pf. is_dir s pf \<and> parent f = Some pf"
+apply (case_tac f)
+apply (simp, drule root_is_dir', simp+)
+apply (simp add:parentf_is_dir_prop2)
+done
 
 lemma enrich_valid_intro_cons:
   assumes vs': "valid s'"
     and os: "os_grant s e" and grant: "grant s e" and vd: "valid s"
     and alive: "\<forall> obj. alive s obj \<longrightarrow> alive s' obj"
     and alive': "\<forall> obj. enrich_not_alive s obj \<longrightarrow> enrich_not_alive s' obj"
+    and hungs: "files_hung_by_del s' = files_hung_by_del s"
     and cp2sp: "\<forall> p. p \<in> current_procs s \<longrightarrow> cp2sproc s' p = cp2sproc s p"
     and cf2sf: "\<forall> f. f \<in> current_files s \<longrightarrow> cf2sfile s' f = cf2sfile s f"
+    and cq2sq: "\<forall> q. q \<in> current_msgqs s \<longrightarrow> cq2smsgq s' q = cq2smsgq s q"
     and ffd_remain: "\<forall> p fd f. file_of_proc_fd s p fd = Some f \<longrightarrow> file_of_proc_fd s' p fd = Some f"
+    and fflags_remain: "\<forall> p fd flags. flags_of_proc_fd s p fd = Some flags \<longrightarrow> flags_of_proc_fd s' p fd = Some flags"
+    and sms_remain: "\<forall> q. msgs_of_queue s' q = msgs_of_queue s q"
+   (* and empty_remain: "\<forall> f. dir_is_empty s f \<longrightarrow> dir_is_empty s' f" *)
     and cfd2sfd: "\<forall> p fd. fd \<in> proc_file_fds s p \<longrightarrow> cfd2sfd s' p fd = cfd2sfd s p fd"
   shows "valid (e # s')"
 proof (cases e)
@@ -209,7 +265,7 @@
     apply (erule_tac x = "O_proc p" in allE)
     by (auto simp:Clone)
   have p'_not_in: "p' \<notin> current_procs s'" using os alive'
-    apply (erule_tac x = "O_proc p'" in allE)
+    apply (erule_tac x = "E_proc p'" in allE)
     by (auto simp:Clone)
   have fd_in: "fds \<subseteq> proc_file_fds s' p" using os alive ffd_remain
     by (auto simp:Clone proc_file_fds_def)
@@ -238,8 +294,764 @@
   ultimately show ?thesis using vs'
     by (erule_tac valid.intros(2), simp+)
 next
+  case (Kill p p')
+  have p_in: "p \<in> current_procs s'" using os alive
+    apply (erule_tac x = "O_proc p" in allE)
+    by (auto simp:Kill)
+  have p'_in: "p' \<in> current_procs s'" using os alive
+    apply (erule_tac x = "O_proc p'" in allE)
+    by (auto simp:Kill)
+  have "os_grant s' e" using p_in p'_in by (simp add:Kill)
+  moreover have "grant s' e" 
+  proof-
+    from grant obtain up rp tp up' rp' tp'
+      where p1: "sectxt_of_obj s (O_proc p) = Some (up, rp, tp)"
+      and p'1: "sectxt_of_obj s (O_proc p') = Some (up', rp', tp')"
+      apply (simp add:Kill split:option.splits)
+      by (case_tac a, case_tac aa, blast)
+    from p1 have p1': "sectxt_of_obj s' (O_proc p) = Some (up, rp, tp)"
+      using os cp2sp
+      apply (erule_tac x = p in allE)
+      by (auto simp:Kill co2sobj.simps cp2sproc_def split:option.splits)
+    from p'1 have p'1': "sectxt_of_obj s' (O_proc p') = Some (up', rp', tp')"
+      using os cp2sp
+      apply (erule_tac x = p' in allE)
+      by (auto simp:Kill co2sobj.simps cp2sproc_def split:option.splits)
+    show ?thesis using p1 p'1 p1' p'1' grant
+      by (simp add:Kill)
+  qed
+  ultimately show ?thesis using vs'
+    by (erule_tac valid.intros(2), simp+)
+next
+  case (Ptrace p p')
+  have p_in: "p \<in> current_procs s'" using os alive
+    apply (erule_tac x = "O_proc p" in allE)
+    by (auto simp:Ptrace)
+  have p'_in: "p' \<in> current_procs s'" using os alive
+    apply (erule_tac x = "O_proc p'" in allE)
+    by (auto simp:Ptrace)
+  have "os_grant s' e" using p_in p'_in by (simp add:Ptrace)
+  moreover have "grant s' e" 
+  proof-
+    from grant obtain up rp tp up' rp' tp'
+      where p1: "sectxt_of_obj s (O_proc p) = Some (up, rp, tp)"
+      and p'1: "sectxt_of_obj s (O_proc p') = Some (up', rp', tp')"
+      apply (simp add:Ptrace split:option.splits)
+      by (case_tac a, case_tac aa, blast)
+    from p1 have p1': "sectxt_of_obj s' (O_proc p) = Some (up, rp, tp)"
+      using os cp2sp
+      apply (erule_tac x = p in allE)
+      by (auto simp:Ptrace co2sobj.simps cp2sproc_def split:option.splits)
+    from p'1 have p'1': "sectxt_of_obj s' (O_proc p') = Some (up', rp', tp')"
+      using os cp2sp
+      apply (erule_tac x = p' in allE)
+      by (auto simp:Ptrace co2sobj.simps cp2sproc_def split:option.splits)
+    show ?thesis using p1 p'1 p1' p'1' grant
+      by (simp add:Ptrace)
+  qed
+  ultimately show ?thesis using vs'
+    by (erule_tac valid.intros(2), simp+)
+next
+  case (Exit p)
+  have p_in: "p \<in> current_procs s'" using os alive
+    apply (erule_tac x = "O_proc p" in allE)
+    by (auto simp:Exit)
+  have "os_grant s' e" using p_in by (simp add:Exit)
+  moreover have "grant s' e" 
+    by (simp add:Exit)
+  ultimately show ?thesis using vs'
+    by (erule_tac valid.intros(2), simp+)
+next
+  case (Open p f flags fd opt)
+  show ?thesis
+  proof (cases opt)
+    case None
+    have p_in: "p \<in> current_procs s'" using os alive
+      apply (erule_tac x = "O_proc p" in allE)
+      by (auto simp:Open None)
+    have f_in: "is_file s' f" using os alive
+      apply (erule_tac x = "O_file f" in allE)
+      by (auto simp:Open None)
+    have fd_not_in: "fd \<notin> current_proc_fds s' p"
+      using os alive' p_in
+      apply (erule_tac x = "E_fd p fd" in allE)
+      by (simp add:Open None)
+    have "os_grant s' e" using p_in f_in fd_not_in os
+      by (simp add:Open None)
+    moreover have "grant s' e" 
+    proof-
+      from grant obtain up rp tp uf rf tf 
+        where p1: "sectxt_of_obj s (O_proc p) = Some (up, rp, tp)"
+        and p2: "sectxt_of_obj s (O_file f) = Some (uf, rf, tf)" 
+        apply (simp add:Open None split:option.splits)
+        by (case_tac a, case_tac aa, blast)
+      from p1 have p1': "sectxt_of_obj s' (O_proc p) = Some (up, rp, tp)"
+        using os cp2sp
+        apply (erule_tac x = p in allE)
+        by (auto simp:Open None co2sobj.simps cp2sproc_def split:option.splits)
+      from os have f_in': "is_file s f" by (simp add:Open None)
+      from vd os have "\<exists> sf. cf2sfile s f = Some sf"
+        by (auto dest!:is_file_in_current current_file_has_sfile simp:Open None)
+      hence p2': "sectxt_of_obj s' (O_file f) = Some (uf, rf, tf)" using f_in f_in' p2 cf2sf
+        apply (erule_tac x = f in allE)
+        apply (auto dest:is_file_in_current simp:cf2sfile_def split:option.splits)
+        apply (case_tac f, simp)
+        apply (drule_tac s = s in root_is_dir', simp add:vd, simp+)
+        done
+      have "search_check s' (up, rp, tp) f"
+        using p1 p2 p2' vd cf2sf f_in' grant Open None f_in
+        apply (rule_tac s = s in enrich_search_check)
+        by (simp_all split:option.splits)
+      thus ?thesis using p1' p2' 
+        apply (simp add:Open None split:option.splits) 
+        using grant Open None p1 p2 
+        by simp
+    qed
+    ultimately show ?thesis using vs'
+      by (erule_tac valid.intros(2), simp+)
+  next
+    case (Some inum)
+    from os obtain pf where pf_in_s: "is_dir s pf" and parent: "parent f = Some pf"
+      by (auto simp:Open Some)
+    have pf_in: "is_dir s' pf" using pf_in_s alive
+      apply (erule_tac x = "O_dir pf" in allE)
+      by simp
+    have p_in: "p \<in> current_procs s'" using os alive
+      apply (erule_tac x = "O_proc p" in allE)
+      by (auto simp:Open Some)
+    have f_not_in: "f \<notin> current_files s'" using os alive'
+      apply (erule_tac x = "E_file f" in allE)
+      by (auto simp:Open Some)
+    have fd_not_in: "fd \<notin> current_proc_fds s' p"
+      using os alive' p_in
+      apply (erule_tac x = "E_fd p fd" in allE)
+      by (simp add:Open Some)
+    have inum_not_in: "inum \<notin> current_inode_nums s'"
+      using os alive' 
+      apply (erule_tac x = "E_inum inum" in allE)
+      by (simp add:Open Some)
+    have "os_grant s' e" using p_in pf_in parent f_not_in fd_not_in inum_not_in os
+      by (simp add:Open Some hungs)
+    moreover have "grant s' e"  
+    proof-
+      from grant parent obtain up rp tp uf rf tf 
+        where p1: "sectxt_of_obj s (O_proc p) = Some (up, rp, tp)"
+        and p2: "sectxt_of_obj s (O_dir pf) = Some (uf, rf, tf)" 
+        apply (simp add:Open Some split:option.splits)
+        by (case_tac a, case_tac aa, blast)
+      from p1 have p1': "sectxt_of_obj s' (O_proc p) = Some (up, rp, tp)"
+        using os cp2sp
+        apply (erule_tac x = p in allE)
+        by (auto simp:Open Some co2sobj.simps cp2sproc_def split:option.splits)
+      from vd os pf_in_s have "\<exists> sf. cf2sfile s pf = Some sf"
+        by (auto dest!:is_dir_in_current current_file_has_sfile simp:Open Some)
+      hence p2': "sectxt_of_obj s' (O_dir pf) = Some (uf, rf, tf)" using p2 cf2sf pf_in pf_in_s
+        apply (erule_tac x = pf in allE)
+        apply (erule exE, frule_tac s = s in is_dir_in_current, simp)
+        apply (drule is_dir_not_file, drule is_dir_not_file)
+        apply (auto simp:cf2sfile_def split:option.splits)
+        apply (case_tac pf, simp_all)
+        by (simp add:sroot_def root_sec_remains vd vs')
+      have "search_check s' (up, rp, tp) pf"
+        using p1 p2 p2' vd cf2sf pf_in grant Open Some pf_in_s parent vs'
+        apply (rule_tac s = s in enrich_search_check')
+        by (simp_all split:option.splits)
+      thus ?thesis using p1' p2' parent 
+        apply (simp add:Open Some split:option.splits) 
+        using grant Open Some p1 p2 
+        by simp
+    qed
+    ultimately show ?thesis using vs'
+      by (erule_tac valid.intros(2), simp+)
+  qed
+next
+  case (ReadFile p fd)
+  have p_in: "p \<in> current_procs s'" using os alive
+    apply (erule_tac x = "O_proc p" in allE)
+    by (auto simp:ReadFile)
+  have fd_in: "fd \<in> current_proc_fds s' p" using os alive
+    apply (erule_tac x = "O_fd p fd" in allE)
+    by (auto simp:ReadFile)
+  obtain f where ffd: "file_of_proc_fd s p fd = Some f"
+    using os ReadFile by auto
+  hence f_in_s: "is_file s f" using vd
+    by (auto intro:file_of_pfd_is_file)
+  obtain flags where fflag: "flags_of_proc_fd s p fd = Some flags"
+    using os ReadFile by auto
+  have ffd_in: "file_of_proc_fd s' p fd = Some f"
+    using ffd_remain ffd by auto
+  hence f_in: "is_file s' f" using vs'
+    by (auto intro:file_of_pfd_is_file)
+  have flags_in: "flags_of_proc_fd s' p fd = Some flags"
+    using fflags_remain fflag by auto
+  have "os_grant s' e" using p_in fd_in ffd_in flags_in fflag os f_in 
+    by (auto simp add:ReadFile is_file_in_current)
+  moreover have "grant s' e" 
+  proof-
+    from grant ffd obtain up rp tp uf rf tf ufd rfd tfd
+      where p1: "sectxt_of_obj s (O_proc p) = Some (up, rp, tp)"
+      and p2: "sectxt_of_obj s (O_file f) = Some (uf, rf, tf)"
+      and p3: "sectxt_of_obj s (O_fd p fd) = Some (ufd, rfd, tfd)"
+      apply (simp add:ReadFile split:option.splits)
+      by (case_tac a, case_tac aa, case_tac ab, blast)
+    from p1 have p1': "sectxt_of_obj s' (O_proc p) = Some (up, rp, tp)"
+      using os cp2sp
+      apply (erule_tac x = p in allE)
+      by (auto simp:ReadFile co2sobj.simps cp2sproc_def split:option.splits)
+    from vd f_in_s have "\<exists> sf. cf2sfile s f = Some sf"
+      by (auto dest!:is_file_in_current current_file_has_sfile)
+    hence p2': "sectxt_of_obj s' (O_file f) = Some (uf, rf, tf)" using f_in f_in_s p2 cf2sf
+      apply (erule_tac x = f in allE)
+      apply (auto dest:is_file_in_current simp:cf2sfile_def split:option.splits)
+      apply (case_tac f, simp)
+      apply (drule_tac s = s in root_is_dir', simp add:vd, simp+)
+      done
+    have p3': "sectxt_of_obj s' (O_fd p fd) = Some (ufd, rfd, tfd)" 
+      using cfd2sfd ffd_in ffd p3 f_in f_in_s vd
+      apply (erule_tac x = p in allE)
+      apply (erule_tac x = fd in allE)
+      apply (simp add:proc_file_fds_def)
+      apply (auto simp:cfd2sfd_def fflag flags_in p3 split:option.splits
+        dest!:current_file_has_sfile' simp:is_file_in_current)
+      done
+    show ?thesis using p1' p2' p3' ffd_in ffd
+      apply (simp add:ReadFile split:option.splits) 
+      using grant p1 p2 p3 ReadFile
+      by simp
+  qed
+  ultimately show ?thesis using vs'
+    by (erule_tac valid.intros(2), simp+)
+next
+  case (WriteFile p fd)
+  have p_in: "p \<in> current_procs s'" using os alive
+    apply (erule_tac x = "O_proc p" in allE)
+    by (auto simp:WriteFile)
+  have fd_in: "fd \<in> current_proc_fds s' p" using os alive
+    apply (erule_tac x = "O_fd p fd" in allE)
+    by (auto simp:WriteFile)
+  obtain f where ffd: "file_of_proc_fd s p fd = Some f"
+    using os WriteFile by auto
+  hence f_in_s: "is_file s f" using vd
+    by (auto intro:file_of_pfd_is_file)
+  obtain flags where fflag: "flags_of_proc_fd s p fd = Some flags"
+    using os WriteFile by auto
+  have ffd_in: "file_of_proc_fd s' p fd = Some f"
+    using ffd_remain ffd by auto
+  hence f_in: "is_file s' f" using vs'
+    by (auto intro:file_of_pfd_is_file)
+  have flags_in: "flags_of_proc_fd s' p fd = Some flags"
+    using fflags_remain fflag by auto
+  have "os_grant s' e" using p_in fd_in ffd_in flags_in fflag os f_in 
+    by (auto simp add:WriteFile is_file_in_current)
+  moreover have "grant s' e" 
+  proof-
+    from grant ffd obtain up rp tp uf rf tf ufd rfd tfd
+      where p1: "sectxt_of_obj s (O_proc p) = Some (up, rp, tp)"
+      and p2: "sectxt_of_obj s (O_file f) = Some (uf, rf, tf)"
+      and p3: "sectxt_of_obj s (O_fd p fd) = Some (ufd, rfd, tfd)"
+      apply (simp add:WriteFile split:option.splits)
+      by (case_tac a, case_tac aa, case_tac ab, blast)
+    from p1 have p1': "sectxt_of_obj s' (O_proc p) = Some (up, rp, tp)"
+      using os cp2sp
+      apply (erule_tac x = p in allE)
+      by (auto simp:WriteFile co2sobj.simps cp2sproc_def split:option.splits)
+    from vd f_in_s have "\<exists> sf. cf2sfile s f = Some sf"
+      by (auto dest!:is_file_in_current current_file_has_sfile)
+    hence p2': "sectxt_of_obj s' (O_file f) = Some (uf, rf, tf)" using f_in f_in_s p2 cf2sf
+      apply (erule_tac x = f in allE)
+      apply (auto dest:is_file_in_current simp:cf2sfile_def split:option.splits)
+      apply (case_tac f, simp)
+      apply (drule_tac s = s in root_is_dir', simp add:vd, simp+)
+      done
+    have p3': "sectxt_of_obj s' (O_fd p fd) = Some (ufd, rfd, tfd)" 
+      using cfd2sfd ffd_in ffd p3 f_in f_in_s vd
+      apply (erule_tac x = p in allE)
+      apply (erule_tac x = fd in allE)
+      apply (simp add:proc_file_fds_def)
+      apply (auto simp:cfd2sfd_def fflag flags_in p3 split:option.splits
+        dest!:current_file_has_sfile' simp:is_file_in_current)
+      done
+    show ?thesis using p1' p2' p3' ffd_in ffd
+      apply (simp add:WriteFile split:option.splits) 
+      using grant p1 p2 p3 WriteFile
+      by simp
+  qed
+  ultimately show ?thesis using vs'
+    by (erule_tac valid.intros(2), simp+)
+next
+  case (CloseFd p fd)
+  have p_in: "p \<in> current_procs s'" using os alive
+    apply (erule_tac x = "O_proc p" in allE)
+    by (auto simp:CloseFd)
+  have fd_in: "fd \<in> current_proc_fds s' p" using os alive
+    apply (erule_tac x = "O_fd p fd" in allE)
+    by (auto simp:CloseFd)
+  have "os_grant s' e" using p_in fd_in 
+    by (auto simp add:CloseFd)
+  moreover have "grant s' e" 
+    by(simp add:CloseFd)
+  ultimately show ?thesis using vs'
+    by (erule_tac valid.intros(2), simp+)
+next
+  case (UnLink p f)
+  have p_in: "p \<in> current_procs s'" using os alive
+    apply (erule_tac x = "O_proc p" in allE)
+    by (auto simp:UnLink)
+  have f_in: "is_file s' f" using os alive
+    apply (erule_tac x = "O_file f" in allE)
+    by (auto simp:UnLink)
+  from os vd obtain pf where pf_in_s: "is_dir s pf"
+    and parent: "parent f = Some pf"
+    by (auto simp:UnLink dest!:file_has_parent)
+  from pf_in_s alive have pf_in: "is_dir s' pf"
+    apply (erule_tac x = "O_dir pf" in allE)
+    by (auto simp:UnLink)
+  have "os_grant s' e" using p_in f_in os
+    by (simp add:UnLink hungs)
+  moreover have "grant s' e" 
+  proof-    
+    from grant parent obtain up rp tp uf rf tf upf rpf tpf
+      where p1: "sectxt_of_obj s (O_proc p) = Some (up, rp, tp)"
+      and p2: "sectxt_of_obj s (O_file f) = Some (uf, rf, tf)" 
+      and p3: "sectxt_of_obj s (O_dir pf) = Some (upf, rpf, tpf)" 
+      apply (simp add:UnLink split:option.splits)
+      by (case_tac a, case_tac aa, case_tac ab, blast) 
+    from p1 have p1': "sectxt_of_obj s' (O_proc p) = Some (up, rp, tp)"
+      using os cp2sp
+      apply (erule_tac x = p in allE)
+      by (auto simp:UnLink co2sobj.simps cp2sproc_def split:option.splits)
+    from vd os pf_in_s have "\<exists> sf. cf2sfile s f = Some sf"
+      by (auto dest!:is_file_in_current current_file_has_sfile simp:UnLink)
+    hence p2': "sectxt_of_obj s' (O_file f) = Some (uf, rf, tf)" 
+      using p2 cf2sf f_in os parent 
+      apply (erule_tac x = f in allE)
+      apply (erule exE, clarsimp simp:UnLink)
+      apply (frule_tac s = s in is_file_in_current, simp)
+      by (auto simp:cf2sfile_def split:option.splits)
+    from vd os pf_in_s have "\<exists> sf. cf2sfile s pf = Some sf"
+      by (auto dest!:is_dir_in_current current_file_has_sfile simp:UnLink)
+    hence p3': "sectxt_of_obj s' (O_dir pf) = Some (upf, rpf, tpf)" using p3 cf2sf pf_in pf_in_s
+      apply (erule_tac x = pf in allE)
+      apply (erule exE, frule_tac s = s in is_dir_in_current, simp)
+      apply (drule is_dir_not_file, drule is_dir_not_file)
+      apply (auto simp:cf2sfile_def split:option.splits)
+      apply (case_tac pf, simp_all)
+      by (simp add:sroot_def root_sec_remains vd vs')
+    have "search_check s' (up, rp, tp) f"
+      using p1 p2 p2' vd cf2sf f_in grant UnLink os parent vs'
+      apply (rule_tac s = s in enrich_search_check)
+      by (simp_all split:option.splits)
+    thus ?thesis using p1' p2' p3' parent 
+      apply (simp add:UnLink split:option.splits) 
+      using grant UnLink p1 p2 p3
+      by simp
+  qed
+  ultimately show ?thesis using vs'
+    by (erule_tac valid.intros(2), simp+)
+next
+  case (Rmdir p f)
+  have p_in: "p \<in> current_procs s'" using os alive
+    apply (erule_tac x = "O_proc p" in allE)
+    by (auto simp:Rmdir)
+  have f_in: "is_dir s' f" using os alive
+    apply (erule_tac x = "O_dir f" in allE)
+    by (auto simp:Rmdir dir_is_empty_def)
+  have not_root: "f \<noteq> []" using os 
+    by (auto simp:Rmdir)
+  from os vd obtain pf where pf_in_s: "is_dir s pf"
+    and parent: "parent f = Some pf"
+    apply (auto simp:Rmdir dir_is_empty_def)
+    apply (case_tac f, simp+)
+    apply (drule parentf_is_dir_prop1, auto)
+    done
+  from pf_in_s alive have pf_in: "is_dir s' pf"
+    apply (erule_tac x = "O_dir pf" in allE)
+    by (auto simp:Rmdir)
+  have empty_in: "dir_is_empty s' f" using os
+    apply (simp add:dir_is_empty_def f_in)
+    apply auto using alive'
+    apply (erule_tac x = "E_file f'" in allE)
+    by (simp add:Rmdir dir_is_empty_def)
+  have "os_grant s' e" using p_in f_in os empty_in
+    by (simp add:Rmdir hungs)
+  moreover have "grant s' e" 
+  proof-
+    from grant parent obtain up rp tp uf rf tf upf rpf tpf
+      where p1: "sectxt_of_obj s (O_proc p) = Some (up, rp, tp)"
+      and p2: "sectxt_of_obj s (O_dir f) = Some (uf, rf, tf)" 
+      and p3: "sectxt_of_obj s (O_dir pf) = Some (upf, rpf, tpf)" 
+      apply (simp add:Rmdir split:option.splits)
+      by (case_tac a, case_tac aa, case_tac ab, blast) 
+    from p1 have p1': "sectxt_of_obj s' (O_proc p) = Some (up, rp, tp)"
+      using os cp2sp
+      apply (erule_tac x = p in allE)
+      by (auto simp:Rmdir co2sobj.simps cp2sproc_def split:option.splits)
+    from vd os pf_in_s have "\<exists> sf. cf2sfile s f = Some sf"
+      by (auto dest!:is_dir_in_current current_file_has_sfile simp:dir_is_empty_def Rmdir)
+    hence p2': "sectxt_of_obj s' (O_dir f) = Some (uf, rf, tf)" 
+      using p2 cf2sf f_in os parent 
+      apply (erule_tac x = f in allE)
+      apply (erule exE, clarsimp simp:Rmdir dir_is_empty_def)
+      apply (frule_tac s = s in is_dir_in_current, simp)
+      apply (drule is_dir_not_file, drule is_dir_not_file)
+      by (auto simp:cf2sfile_def split:option.splits)
+    from vd os pf_in_s have "\<exists> sf. cf2sfile s pf = Some sf"
+      by (auto dest!:is_dir_in_current current_file_has_sfile simp:Rmdir)
+    hence p3': "sectxt_of_obj s' (O_dir pf) = Some (upf, rpf, tpf)" using p3 cf2sf pf_in pf_in_s
+      apply (erule_tac x = pf in allE)
+      apply (erule exE, frule_tac s = s in is_dir_in_current, simp)
+      apply (drule is_dir_not_file, drule is_dir_not_file)
+      apply (auto simp:cf2sfile_def split:option.splits)
+      apply (case_tac pf, simp_all)
+      by (simp add:sroot_def root_sec_remains vd vs')
+    have "search_check s' (up, rp, tp) f"
+      using p1 p2 p2' vd cf2sf f_in grant Rmdir os parent vs'
+      apply (rule_tac s = s in enrich_search_check')
+      by (simp_all add:dir_is_empty_def split:option.splits)
+    thus ?thesis using p1' p2' p3' parent 
+      apply (simp add:Rmdir split:option.splits) 
+      using grant Rmdir p1 p2 p3
+      by simp
+  qed
+  ultimately show ?thesis using vs'
+    by (erule_tac valid.intros(2), simp+)
+next
+  case (Mkdir p f inum)
+  from os obtain pf where pf_in_s: "is_dir s pf" and parent: "parent f = Some pf"
+    by (auto simp:Mkdir)
+  have pf_in: "is_dir s' pf" using pf_in_s alive
+    apply (erule_tac x = "O_dir pf" in allE)
+    by simp
+  have p_in: "p \<in> current_procs s'" using os alive
+    apply (erule_tac x = "O_proc p" in allE)
+    by (auto simp:Mkdir)
+  have f_not_in: "f \<notin> current_files s'" using os alive'
+    apply (erule_tac x = "E_file f" in allE)
+    by (auto simp:Mkdir)
+  have inum_not_in: "inum \<notin> current_inode_nums s'"
+    using os alive' 
+    apply (erule_tac x = "E_inum inum" in allE)
+    by (simp add:Mkdir)
+  have "os_grant s' e" using p_in pf_in parent f_not_in os inum_not_in
+    by (simp add:Mkdir hungs)
+  moreover have "grant s' e"  
+  proof-
+    from grant parent obtain up rp tp uf rf tf 
+      where p1: "sectxt_of_obj s (O_proc p) = Some (up, rp, tp)"
+      and p2: "sectxt_of_obj s (O_dir pf) = Some (uf, rf, tf)" 
+      apply (simp add:Mkdir split:option.splits)
+      by (case_tac a, case_tac aa, blast)
+    from p1 have p1': "sectxt_of_obj s' (O_proc p) = Some (up, rp, tp)"
+      using os cp2sp
+      apply (erule_tac x = p in allE)
+      by (auto simp:Mkdir co2sobj.simps cp2sproc_def split:option.splits)
+    from vd os pf_in_s have "\<exists> sf. cf2sfile s pf = Some sf"
+      by (auto dest!:is_dir_in_current current_file_has_sfile simp:Mkdir)
+    hence p2': "sectxt_of_obj s' (O_dir pf) = Some (uf, rf, tf)" using p2 cf2sf pf_in pf_in_s
+      apply (erule_tac x = pf in allE)
+      apply (erule exE, frule_tac s = s in is_dir_in_current, simp)
+      apply (drule is_dir_not_file, drule is_dir_not_file)
+      apply (auto simp:cf2sfile_def split:option.splits)
+      apply (case_tac pf, simp_all)
+      by (simp add:sroot_def root_sec_remains vd vs')
+    have "search_check s' (up, rp, tp) pf"
+      using p1 p2 p2' vd cf2sf pf_in grant Mkdir pf_in_s parent vs'
+      apply (rule_tac s = s in enrich_search_check')
+      apply (simp_all split:option.splits)
+      done
+    thus ?thesis using p1' p2' parent 
+      apply (simp add:Mkdir split:option.splits) 
+      using grant Mkdir p1 p2 
+      apply simp 
+      done
+  qed
+  ultimately show ?thesis using vs'
+    by (erule_tac valid.intros(2), simp+)
+next
+  case (LinkHard p f f')
+  from os obtain pf where pf_in_s: "is_dir s pf" and parent: "parent f' = Some pf"
+    by (auto simp:LinkHard)
+  have pf_in: "is_dir s' pf" using pf_in_s alive
+    apply (erule_tac x = "O_dir pf" in allE)
+    by simp
+  have p_in: "p \<in> current_procs s'" using os alive
+    apply (erule_tac x = "O_proc p" in allE)
+    by (auto simp:LinkHard)
+  have f'_not_in: "f' \<notin> current_files s'" using os alive'
+    apply (erule_tac x = "E_file f'" in allE)
+    by (auto simp:LinkHard)
+  have f_in: "is_file s' f" using os alive
+    apply (erule_tac x = "O_file f" in allE)
+    by (auto simp:LinkHard)
+  have "os_grant s' e" using p_in pf_in parent os f_in f'_not_in
+    by (simp add:LinkHard hungs)
+  moreover have "grant s' e"
+  proof-
+    from grant parent obtain up rp tp uf rf tf upf rpf tpf
+      where p1: "sectxt_of_obj s (O_proc p) = Some (up, rp, tp)"
+      and p2: "sectxt_of_obj s (O_file f) = Some (uf, rf, tf)" 
+      and p3: "sectxt_of_obj s (O_dir pf) = Some (upf, rpf, tpf)" 
+      apply (simp add:LinkHard split:option.splits)
+      by (case_tac a, case_tac aa, case_tac ab, blast) 
+    from p1 have p1': "sectxt_of_obj s' (O_proc p) = Some (up, rp, tp)"
+      using os cp2sp
+      apply (erule_tac x = p in allE)
+      by (auto simp:LinkHard co2sobj.simps cp2sproc_def split:option.splits)
+    from vd os pf_in_s have "\<exists> sf. cf2sfile s f = Some sf"
+      by (auto dest!:is_file_in_current current_file_has_sfile simp:LinkHard)
+    hence p2': "sectxt_of_obj s' (O_file f) = Some (uf, rf, tf)" 
+      using p2 cf2sf f_in os parent 
+      apply (erule_tac x = f in allE)
+      apply (erule exE, clarsimp simp:LinkHard)
+      apply (frule_tac s = s in is_file_in_current, simp)
+      apply (auto simp:cf2sfile_def split:option.splits)
+      apply (case_tac f, simp)
+      by (drule_tac s = s in root_is_dir', simp add:vd, simp+)
+    from vd os pf_in_s have "\<exists> sf. cf2sfile s pf = Some sf"
+      by (auto dest!:is_dir_in_current current_file_has_sfile simp:LinkHard)
+    hence p3': "sectxt_of_obj s' (O_dir pf) = Some (upf, rpf, tpf)" using p3 cf2sf pf_in pf_in_s
+      apply (erule_tac x = pf in allE)
+      apply (erule exE, frule_tac s = s in is_dir_in_current, simp)
+      apply (drule is_dir_not_file, drule is_dir_not_file)
+      apply (auto simp:cf2sfile_def split:option.splits)
+      apply (case_tac pf, simp_all)
+      by (simp add:sroot_def root_sec_remains vd vs')
+    have "search_check s' (up, rp, tp) f"
+      using p1 p2 p2' vd cf2sf f_in grant LinkHard os parent vs'
+      apply (rule_tac s = s in enrich_search_check)
+      by (simp_all split:option.splits)
+    moreover have "search_check s' (up, rp, tp) pf"
+      using p1 p3 p3' vd cf2sf pf_in grant LinkHard os parent vs'
+      apply (rule_tac s = s in enrich_search_check')
+      apply (simp_all split:option.splits)
+      done
+    ultimately show ?thesis using p1' p2' p3' parent 
+      apply (simp add:LinkHard split:option.splits) 
+      using grant LinkHard p1 p2 p3
+      apply simp 
+      done
+  qed
+  ultimately show ?thesis using vs'
+    by (erule_tac valid.intros(2), simp+)
+next
+  case (Truncate p f len)
+  have p_in: "p \<in> current_procs s'" using os alive
+    apply (erule_tac x = "O_proc p" in allE)
+    by (auto simp:Truncate)
+  have f_in: "is_file s' f" using os alive
+    apply (erule_tac x = "O_file f" in allE)
+    by (auto simp:Truncate)
+  have "os_grant s' e" using p_in f_in by (simp add:Truncate)
+  moreover have "grant s' e"
+  proof-
+    from grant obtain up rp tp uf rf tf 
+      where p1: "sectxt_of_obj s (O_proc p) = Some (up, rp, tp)"
+      and p2: "sectxt_of_obj s (O_file f) = Some (uf, rf, tf)" 
+      apply (simp add:Truncate split:option.splits)
+      by (case_tac a, case_tac aa, blast)
+    from p1 have p1': "sectxt_of_obj s' (O_proc p) = Some (up, rp, tp)"
+      using os cp2sp
+      apply (erule_tac x = p in allE)
+      by (auto simp:Truncate co2sobj.simps cp2sproc_def split:option.splits)
+    from os have f_in': "is_file s f" by (simp add:Truncate)
+    from vd os have "\<exists> sf. cf2sfile s f = Some sf"
+      by (auto dest!:is_file_in_current current_file_has_sfile simp:Truncate)
+    hence p2': "sectxt_of_obj s' (O_file f) = Some (uf, rf, tf)" using f_in f_in' p2 cf2sf
+      apply (erule_tac x = f in allE)
+      apply (auto dest:is_file_in_current simp:cf2sfile_def split:option.splits)
+      apply (case_tac f, simp)
+      apply (drule_tac s = s in root_is_dir', simp add:vd, simp+)
+      done
+    have "search_check s' (up, rp, tp) f"
+      using p1 p2 p2' vd cf2sf f_in' grant Truncate f_in
+      apply (rule_tac s = s in enrich_search_check)
+      by (simp_all split:option.splits)
+    thus ?thesis using p1' p2' 
+      apply (simp add:Truncate split:option.splits) 
+      using grant Truncate p1 p2
+      by (simp add:Truncate grant p1 p2)
+  qed
+  ultimately show ?thesis using vs'
+    by (erule_tac valid.intros(2), simp+)
+next
+  case (CreateMsgq p q)
+  have p_in: "p \<in> current_procs s'" using os alive
+    apply (erule_tac x = "O_proc p" in allE)
+    by (auto simp:CreateMsgq)
+  have q_not_in: "q \<notin> current_msgqs s'" using os alive'
+    apply (erule_tac x = "E_msgq q" in allE)
+    by (simp add:CreateMsgq)
+  have "os_grant s' e" using p_in q_not_in by (simp add:CreateMsgq)
+  moreover have "grant s' e" 
+  proof-
+    from grant obtain up rp tp 
+      where p1: "sectxt_of_obj s (O_proc p) = Some (up, rp, tp)"
+      apply (simp add:CreateMsgq split:option.splits)
+      by (case_tac a, blast)
+    from p1 have p1': "sectxt_of_obj s' (O_proc p) = Some (up, rp, tp)"
+      using os cp2sp
+      apply (erule_tac x = p in allE)
+      by (auto simp:CreateMsgq co2sobj.simps cp2sproc_def split:option.splits)
+    show ?thesis using p1' 
+      apply (simp add:CreateMsgq split:option.splits) 
+      using grant CreateMsgq p1
+      by simp
+  qed
+  ultimately show ?thesis using vs'
+    by (erule_tac valid.intros(2), simp+)
+next
+  case (RemoveMsgq p q)
+  have p_in: "p \<in> current_procs s'" using os alive
+    apply (erule_tac x = "O_proc p" in allE)
+    by (auto simp:RemoveMsgq)
+  have q_in: "q \<in> current_msgqs s'" using os alive
+    apply (erule_tac x = "O_msgq q" in allE)
+    by (simp add:RemoveMsgq)
+  have "os_grant s' e" using p_in q_in by (simp add:RemoveMsgq)
+  moreover have "grant s' e" 
+  proof-
+    from grant obtain up rp tp uq rq tq
+      where p1: "sectxt_of_obj s (O_proc p) = Some (up, rp, tp)"
+      and p2: "sectxt_of_obj s (O_msgq q) = Some (uq, rq, tq)"
+      apply (simp add:RemoveMsgq split:option.splits)
+      by (case_tac a, case_tac aa, blast)
+    from p1 have p1': "sectxt_of_obj s' (O_proc p) = Some (up, rp, tp)"
+      using os cp2sp
+      apply (erule_tac x = p in allE)
+      by (auto simp:RemoveMsgq co2sobj.simps cp2sproc_def split:option.splits)
+    from p2 have p2': "sectxt_of_obj s' (O_msgq q) = Some (uq, rq, tq)"
+      using os cq2sq vd
+      apply (erule_tac x = q in allE)
+      by (auto simp:RemoveMsgq co2sobj.simps cq2smsgq_def dest!:current_has_sms' split:option.splits)
+    show ?thesis using p1' p2' grant p1 p2
+      by (simp add:RemoveMsgq)
+  qed
+  ultimately show ?thesis using vs'
+    by (erule_tac valid.intros(2), simp+)  
+next
+  case (SendMsg p q m)
+  have p_in: "p \<in> current_procs s'" using os alive
+    apply (erule_tac x = "O_proc p" in allE)
+    by (auto simp:SendMsg)
+  have q_in: "q \<in> current_msgqs s'" using os alive
+    apply (erule_tac x = "O_msgq q" in allE)
+    by (simp add:SendMsg)
+  have m_not_in: "m \<notin> set (msgs_of_queue s' q)" using os alive'
+    apply (erule_tac x = "E_msg q m" in allE)
+    by (simp add:SendMsg q_in)
+  have "os_grant s' e" using p_in q_in m_not_in
+    by (simp add:SendMsg)
+  moreover have "grant s' e" 
+  proof-
+    from grant obtain up rp tp uq rq tq
+      where p1: "sectxt_of_obj s (O_proc p) = Some (up, rp, tp)"
+      and p2: "sectxt_of_obj s (O_msgq q) = Some (uq, rq, tq)"
+      apply (simp add:SendMsg split:option.splits)
+      by (case_tac a, case_tac aa, blast)
+    from p1 have p1': "sectxt_of_obj s' (O_proc p) = Some (up, rp, tp)"
+      using os cp2sp
+      apply (erule_tac x = p in allE)
+      by (auto simp:SendMsg co2sobj.simps cp2sproc_def split:option.splits)
+    from p2 have p2': "sectxt_of_obj s' (O_msgq q) = Some (uq, rq, tq)"
+      using os cq2sq vd
+      apply (erule_tac x = q in allE)
+      by (auto simp:SendMsg co2sobj.simps cq2smsgq_def dest!:current_has_sms' split:option.splits)
+    show ?thesis using p1' p2' grant p1 p2
+      by (simp add:SendMsg)
+  qed
+  ultimately show ?thesis using vs'
+    by (erule_tac valid.intros(2), simp+)  
+next
+  case (RecvMsg p q m)
+  have p_in: "p \<in> current_procs s'" using os alive
+    apply (erule_tac x = "O_proc p" in allE)
+    by (auto simp:RecvMsg)
+  have q_in: "q \<in> current_msgqs s'" using os alive
+    apply (erule_tac x = "O_msgq q" in allE)
+    by (simp add:RecvMsg) 
+  have m_in: "m = hd (msgs_of_queue s' q)" 
+    and sms_not_empty: "msgs_of_queue s' q \<noteq> []"
+    using os sms_remain
+    by (auto simp:RecvMsg)
+  have "os_grant s' e" using p_in q_in m_in sms_not_empty os
+    by (simp add:RecvMsg)
+  moreover have "grant s' e" 
+  proof-
+    from grant obtain up rp tp uq rq tq um rm tm
+      where p1: "sectxt_of_obj s (O_proc p) = Some (up, rp, tp)"
+      and p2: "sectxt_of_obj s (O_msgq q) = Some (uq, rq, tq)"
+      and p3: "sectxt_of_obj s (O_msg q m) = Some (um, rm, tm)"
+      apply (simp add:RecvMsg split:option.splits)
+      by (case_tac a, case_tac aa, case_tac ab, blast)
+    from p1 have p1': "sectxt_of_obj s' (O_proc p) = Some (up, rp, tp)"
+      using os cp2sp
+      apply (erule_tac x = p in allE)
+      by (auto simp:RecvMsg co2sobj.simps cp2sproc_def split:option.splits)
+    from p2 have p2': "sectxt_of_obj s' (O_msgq q) = Some (uq, rq, tq)"
+      using os cq2sq vd
+      apply (erule_tac x = q in allE)
+      by (auto simp:RecvMsg co2sobj.simps cq2smsgq_def dest!:current_has_sms' split:option.splits)
+    from p3 have p3': "sectxt_of_obj s' (O_msg q m) = Some (um, rm, tm)"
+      using sms_remain cq2sq vd os p2 p2' p3 
+      apply (erule_tac x = q in allE)
+      apply (erule_tac x = q in allE)
+      apply (clarsimp simp:RecvMsg)
+      apply (simp add:cq2smsgq_def split:option.splits if_splits)
+      apply (drule current_has_sms', simp, simp)
+      apply (case_tac "msgs_of_queue s q", simp)
+      apply (simp add:cqm2sms.simps split:option.splits)
+      apply (auto simp add:cm2smsg_def split:option.splits if_splits)[1]
+      apply (case_tac "msgs_of_queue s q", simp)
+      apply (simp add:cqm2sms.simps split:option.splits)
+      apply (auto simp add:cm2smsg_def split:option.splits if_splits)[1]
+      done
+    show ?thesis using p1' p2' p3' grant p1 p2 p3
+      by (simp add:RecvMsg)
+  qed
+  ultimately show ?thesis using vs'
+    by (erule_tac valid.intros(2), simp+)  
+next
+  case (CreateSock p af st fd inum)
+  show ?thesis using grant
+    by (simp add:CreateSock)
+next
+  case (Bind p fd addr)
+  show ?thesis using grant
+    by (simp add:Bind)
+next
+  case (Connect p fd addr)
+  show ?thesis using grant
+    by (simp add:Connect)
+next
+  case (Listen p fd)
+  show ?thesis using grant
+    by (simp add:Listen)
+next
+  case (Accept p fd addr port fd' inum)
+  show ?thesis using grant
+    by (simp add:Accept)
+next
+  case (SendSock p fd)
+  show ?thesis using grant
+    by (simp add:SendSock)
+next
+  case (RecvSock p fd)
+  show ?thesis using grant
+    by (simp add:RecvSock)
+next
+  case (Shutdown p fd how)
+  show ?thesis using grant
+    by (simp add:Shutdown)
+qed  
   
-
+  
+  
+  
+  
+  
+  
+  
+    
 
 
 
--- a/no_shm_selinux/Flask.thy	Tue Dec 17 13:30:21 2013 +0800
+++ b/no_shm_selinux/Flask.thy	Wed Dec 18 10:44:36 2013 +0800
@@ -1378,7 +1378,7 @@
        Some pf \<Rightarrow> 
          (case (sectxt_of_obj s (O_proc p), sectxt_of_obj s (O_dir pf)) of 
            (Some (pu,pr,pt), Some (du,dr,dt)) \<Rightarrow> 
-             (search_check s (pu,pr,pt) f \<and> 
+             (search_check s (pu,pr,pt) pf \<and> 
               permission_check (pu,pr,pt) (nfctxt_create (pu,pr,pt) (du,dr,dt) C_dir) C_dir P_create \<and>
               permission_check (pu,pr,pt) (du,dr,dt) C_dir P_add_name)
          | _ \<Rightarrow> False)