no_shm_selinux/Enrich.thy
author chunhan
Wed, 18 Dec 2013 10:44:36 +0800
changeset 78 030643fab8a1
parent 77 6f7b9039715f
child 79 c09fcbcdb871
permissions -rw-r--r--
Enrich

theory Enrich
imports Main Flask Static Init_prop Valid_prop Tainted_prop Delete_prop Co2sobj_prop S2ss_prop S2ss_prop2
 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 *)
fun enrich_proc :: "t_state \<Rightarrow> t_process \<Rightarrow> t_process \<Rightarrow> t_state"
where 
  "enrich_proc [] tp dp = []"
| "enrich_proc (Execve p f fds # s) tp dp = (
     if (tp = p) 
     then Execve dp f (fds \<inter> proc_file_fds s p) # Execve p f fds # (enrich_proc s tp dp)
     else Execve p f fds # (enrich_proc s tp dp))"
| "enrich_proc (Clone p p' fds # s) tp dp = (
     if (tp = p') 
     then Clone p dp (fds \<inter> proc_file_fds s p) # Clone p p' fds # s
     else Clone p p' fds # (enrich_proc s tp dp))"
| "enrich_proc (Open p f flags fd opt # s) tp dp = (
     if (tp = p)
     then Open dp f (remove_create_flag flags) fd opt # Open p f flags fd opt # (enrich_proc s tp dp)
     else Open p f flags fd opt # (enrich_proc s tp dp))"
| "enrich_proc (CloseFd p fd # s) tp dp = (
     if (tp = p)
     then CloseFd dp fd # CloseFd p fd # (enrich_proc s tp dp)
     else CloseFd p fd # (enrich_proc s tp dp))"
(*
| "enrich_proc (Attach p h flag # s) tp dp = (
     if (tp = p)
     then Attach dp h flag # Attach p h flag # (enrich_proc s tp dp)
     else Attach p h flag # (enrich_proc s tp dp))"
| "enrich_proc (Detach p h # s) tp dp = (
     if (tp = p) 
     then Detach dp h # Detach p h # (enrich_proc s tp dp)
     else Detach p h # (enrich_proc s tp dp))"
*)
| "enrich_proc (Kill p p' # s) tp dp = (
     if (tp = p) then Kill p p' # s
     else Kill p p' # (enrich_proc s tp dp))"
| "enrich_proc (Exit p # s) tp dp = (
     if (tp = p) then Exit p # s
     else Exit p # (enrich_proc s tp dp))"
| "enrich_proc (e # s) tp dp = e # (enrich_proc s tp dp)"

definition is_created_proc:: "t_state \<Rightarrow> t_process \<Rightarrow> bool"
where
  "is_created_proc s p \<equiv> p \<in> init_procs \<longrightarrow> died (O_proc p) s"

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 f_in: "is_file s f"  and f_in': "is_file s' f"
  and sec: "sectxt_of_obj s' (O_file f) = sectxt_of_obj s (O_file f)"
  shows "search_check s' (up, rp, tp) f"
proof (cases f)
  case Nil
  with f_in vd have "False" 
    by (auto dest:root_is_dir') 
  thus ?thesis by simp
next
  case (Cons n pf)
  from vd f_in obtain sf where sf: "cf2sfile s f = Some sf"
    apply (drule_tac is_file_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_file_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 (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 (simp add:Cons split:option.splits)
    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)
done

lemma enrich_inherit_fds_check:
  assumes grant: "inherit_fds_check s (up, nr, nt) p fds"  and vd: "valid s"
  and cfd2sfd: "\<forall> p fd. fd \<in> proc_file_fds s p\<longrightarrow> cfd2sfd s' p fd = cfd2sfd s p fd"
  and fd_in: "fds \<subseteq> proc_file_fds s p" and fd_in': "fds \<subseteq> proc_file_fds s' p"
  shows "inherit_fds_check s' (up, nr, nt) p fds"
proof-
  have "\<And> fd. fd \<in> fds \<Longrightarrow> sectxt_of_obj s' (O_fd p fd) = sectxt_of_obj s (O_fd p fd)"
  proof-
    fix fd
    assume fd_in_fds: "fd \<in> fds"
    hence fd_in_cfds: "fd \<in> proc_file_fds s p" 
      and fd_in_cfds': "fd \<in> proc_file_fds s' p" 
      using fd_in fd_in' by auto
    with cfd2sfd
    have cfd_eq: "cfd2sfd s' p fd = cfd2sfd s p fd" by auto
    from fd_in_cfds obtain f where ffd: "file_of_proc_fd s p fd = Some f"
      by (auto simp:proc_file_fds_def)
    moreover have "flags_of_proc_fd s p fd \<noteq> None"
      using ffd vd by (auto dest:current_filefd_has_flags)
    moreover have "sectxt_of_obj s (O_fd p fd) \<noteq> None"
      using fd_in_cfds vd
      apply (rule_tac notI)
      by (auto dest!:current_has_sec' file_fds_subset_pfds[where p = p] intro:vd)
    moreover have "cf2sfile s f \<noteq> None"
      apply (rule notI)
      apply (drule current_file_has_sfile')
      using ffd
      by (auto simp:vd is_file_in_current dest:file_of_pfd_is_file)
    ultimately show "sectxt_of_obj s' (O_fd p fd) = sectxt_of_obj s (O_fd p fd)"
      using cfd_eq
      by (auto simp:cfd2sfd_def split:option.splits)
  qed
  hence "sectxts_of_fds s' p fds = sectxts_of_fds s p fds"
    by (simp add:sectxts_of_fds_def)
  thus ?thesis using grant
    by (simp add:inherit_fds_check_def)
qed

lemma not_all_procs_cons:
  "p \<notin> all_procs (e # s) \<Longrightarrow> p \<notin> all_procs s"
by (case_tac e, auto)

lemma not_all_procs_prop:
  "\<lbrakk>p' \<notin> all_procs s; p \<in> current_procs s; valid s\<rbrakk> \<Longrightarrow> p' \<noteq> p"
apply (induct s, rule notI, simp)
apply (frule vt_grant_os, frule vd_cons, frule not_all_procs_cons, simp, rule notI)
apply (case_tac a, auto)
done

fun enrich_not_alive :: "t_state \<Rightarrow> t_enrich_obj \<Rightarrow> bool"
where
  "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)
  case (Execve p f fds)
  have p_in: "p \<in> current_procs s'" using os alive
    apply (erule_tac x = "O_proc p" in allE)
    by (auto simp:Execve)
  have f_in: "is_file s' f" using os alive
    apply (erule_tac x = "O_file f" in allE)
    by (auto simp:Execve)
  have fd_in: "fds \<subseteq> proc_file_fds s' p" using os alive ffd_remain
    by (auto simp:Execve proc_file_fds_def)
  have "os_grant s' e" using p_in f_in fd_in by (simp add:Execve)
  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)" 
      by (simp add:Execve split:option.splits, blast)
    with grant obtain pu nr nt where p3: "npctxt_execve (up, rp, tp) (uf, rf, tf) = Some (pu, nr, nt)"
      by (simp add:Execve split:option.splits del:npctxt_execve.simps, 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:Execve co2sobj.simps cp2sproc_def split:option.splits)
    from os have f_in': "is_file s f" by (simp add:Execve)
    from vd os have "\<exists> sf. cf2sfile s f = Some sf"
      by (auto dest!:is_file_in_current current_file_has_sfile simp:Execve)
    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 "inherit_fds_check s' (pu, nr, nt) p fds"
    proof-
      have "fds \<subseteq> proc_file_fds s' p" using os ffd_remain Execve
        by (auto simp:proc_file_fds_def)
      thus ?thesis using Execve grant vd cfd2sfd p1 p2 p3 os
        apply (rule_tac s = s in enrich_inherit_fds_check)
        by (simp_all split:option.splits)
    qed
    moreover have "search_check s' (pu, rp, tp) f"
      using p1 p2 p2' vd cf2sf f_in' grant Execve p3 f_in
      apply (rule_tac s = s in enrich_search_check)
      by (simp_all split:option.splits)
    ultimately show ?thesis using p1' p2' p3
      apply (simp add:Execve split:option.splits) 
      using grant Execve p1 p2
      by (simp add:Execve grant p1 p2)
  qed
  ultimately show ?thesis using vs'
    by (erule_tac valid.intros(2), simp+)
next
  case (Clone p p' fds)
  have p_in: "p \<in> current_procs s'" using os alive
    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 = "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)
  have "os_grant s' e" using p_in p'_not_in fd_in by (simp add:Clone)
  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:Clone split:option.splits)
      by (case_tac a, auto)
    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:Clone co2sobj.simps cp2sproc_def split:option.splits)
    have p2: "inherit_fds_check s' (up, rp, tp) p fds"
    proof-
      have "fds \<subseteq> proc_file_fds s' p" using os ffd_remain Clone
        by (auto simp:proc_file_fds_def)
      thus ?thesis using Clone grant vd cfd2sfd p1 os
        apply (rule_tac s = s in enrich_inherit_fds_check)
        by (simp_all split:option.splits)
    qed
    show ?thesis using p1 p2 p1' grant
      by (simp add:Clone)
  qed
  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  
  
  
  
  
  
  
  
  
    




    

lemma enrich_proc_prop:
  "\<lbrakk>valid s; is_created_proc s p; p' \<notin> all_procs s\<rbrakk>
   \<Longrightarrow> valid (enrich_proc s p p') \<and> 
       (p \<in> current_procs s \<longrightarrow> co2sobj (enrich_proc s p p') (O_proc p') = co2sobj (enrich_proc s p p') (O_proc p)) \<and>
       (\<forall> obj. alive s obj \<longrightarrow> alive (enrich_proc s p p')  obj) \<and> 
       (\<forall> p'. p' \<in> current_procs s \<longrightarrow> cp2sproc (enrich_proc s p p') p' = cp2sproc s p) \<and>
       (\<forall> f. f \<in> current_files s \<longrightarrow> cf2sfile (enrich_proc s p p') f = cf2sfile s f) \<and>
       (Tainted (enrich_proc s p p') = (Tainted s \<union> (if (O_proc p \<in> Tainted s) then {O_proc p'} else {})))"
proof (induct s)
  case Nil
  thus ?case by (auto simp:is_created_proc_def)
next
  case (Cons e s)
  hence p1: "\<lbrakk>valid s; is_created_proc s p; p' \<notin> all_procs s\<rbrakk>
  \<Longrightarrow> valid (enrich_proc s p p') \<and>
     (p \<in> current_procs s \<longrightarrow> co2sobj (enrich_proc s p p') (O_proc p') = co2sobj (enrich_proc s p p') (O_proc p)) \<and>
     (alive s obj \<longrightarrow> alive (enrich_proc s p p') obj \<and> co2sobj (enrich_proc s p p') obj = co2sobj s obj)"
    and p2: "valid (e # s)" and p3: "is_created_proc (e # s) p" and p4: "p' \<notin> all_procs (e # s)"
    by auto
  from p2 have vd: "valid s" and os: "os_grant s e" and grant: "grant s e"
    by (auto dest:vd_cons vt_grant vt_grant_os)
  from p4 have p4': "p' \<notin> all_procs s" by (case_tac e, auto)
  from p1 p4' have a1: "is_created_proc s p \<Longrightarrow> valid (enrich_proc s p p')" by (auto simp:vd)
  have c1: "valid (enrich_proc (e # s) p p')"
    apply (case_tac e)
    using a1 os p3
    apply (auto simp:is_created_proc_def)
    sorry
  moreover have c2: "p' \<in> current_procs (enrich_proc (e # s) p p')"
    sorry
  moreover have c3: "co2sobj (enrich_proc (e # s) p p') (O_proc p') = co2sobj (enrich_proc (e # s) p p') (O_proc p)"
    sorry
  moreover have c4: "alive (e # s) obj \<longrightarrow>
     alive (enrich_proc (e # s) p p') obj \<and> co2sobj (enrich_proc (e # s) p p') obj = co2sobj (e # s) obj"
    sorry
  ultimately show ?case by auto
qed