del_vs_del_s.thy
changeset 1 dcde836219bc
child 6 4294abb1f38c
equal deleted inserted replaced
0:b992684e9ff6 1:dcde836219bc
       
     1 theory del_vs_del_s
       
     2 imports Main rc_theory os_rc obj2sobj_prop all_sobj_prop 
       
     3 begin
       
     4 
       
     5 context tainting_s_complete begin
       
     6 
       
     7 lemma deleted_has_del_event_proc:
       
     8   "\<lbrakk>deleted (Proc p) s; valid s\<rbrakk> \<Longrightarrow> \<exists> s' p'. Kill p' p # s' \<preceq> s \<and> \<not> deleted (Proc p) s'"
       
     9 apply (induct s, simp)
       
    10 apply (frule valid_cons, frule valid_os)
       
    11 by (case_tac a, auto simp:no_junior_def)
       
    12 
       
    13 lemma deleted_has_del_event_ipc:
       
    14   "\<lbrakk>deleted (IPC i) s; valid s\<rbrakk> \<Longrightarrow> \<exists> s' p. DeleteIPC p i # s' \<preceq> s \<and> \<not> deleted (IPC i) s'"
       
    15 apply (induct s, simp)
       
    16 apply (frule valid_cons, frule valid_os)
       
    17 by (case_tac a, auto simp:no_junior_def)
       
    18 
       
    19 lemma deleted_has_del_event_file:
       
    20   "\<lbrakk>deleted (File f) s; valid s\<rbrakk> \<Longrightarrow> \<exists> s' p. DeleteFile p f # s' \<preceq> s \<and> \<not> deleted (File f) s'"
       
    21 apply (induct s, simp)
       
    22 apply (frule valid_cons, frule valid_os)
       
    23 by (case_tac a, auto simp:no_junior_def)
       
    24 
       
    25 (*
       
    26 lemma noJ_Anc: "x \<prec> y = (x \<preceq> y \<and> x \<noteq> y)"
       
    27 apply (simp add: no_junior_expand)
       
    28 by (auto simp:is_ancestor_def)
       
    29 
       
    30 lemma noJ_Anc': "x \<prec> y \<Longrightarrow> (x \<preceq> y \<and> x \<noteq> y)"
       
    31 by (simp add:noJ_Anc)
       
    32 
       
    33 lemma noJ_Anc'': "\<lbrakk>x \<preceq> y; x \<noteq> y\<rbrakk> \<Longrightarrow> x \<prec> y"
       
    34 by (simp add:noJ_Anc)
       
    35 
       
    36 lemma deled_imp_no_childfs:
       
    37   "\<lbrakk>valid (DeleteFile p f # s); f \<prec> childf\<rbrakk> \<Longrightarrow> childf \<notin> current_files s"
       
    38 apply (frule valid_cons, drule valid_os, rule notI, clarsimp dest!:noJ_Anc')
       
    39 apply (drule ancient_has_parent, simp, clarsimp)
       
    40 apply (drule_tac af = sonf and f = childf in ancient_file_in_current, simp+)
       
    41 apply (case_tac sonf, simp)
       
    42 apply (erule_tac x = a in allE, simp)
       
    43 done
       
    44 
       
    45 lemma deled_imp_childfs_deleted:
       
    46   "\<lbrakk>valid (DeleteFile p f # s); f \<prec> childf; childf \<in> init_files\<rbrakk>
       
    47   \<Longrightarrow> deleted (File childf) s"
       
    48 apply (drule deled_imp_no_childfs, simp+)
       
    49 apply (erule_tac P = "childf \<in> current_files s" in swap)
       
    50 by (drule not_deleted_imp_exists, simp+)
       
    51 
       
    52 lemma initf_deled_imp_childf_deled:
       
    53   "\<lbrakk>deleted (File f) s; valid s\<rbrakk> \<Longrightarrow> \<exists> s' p. DeleteFile p f # s' \<preceq> s \<and> \<not> deleted (File f) s' \<and> (\<forall> childf \<in> init_files. f \<prec> childf \<longrightarrow> deleted (File childf) s')"
       
    54 apply (drule deleted_has_del_event_file, simp, clarify)
       
    55 apply (rule_tac x = s' in exI, rule_tac x = p in exI, simp)
       
    56 apply (rule ballI, rule impI, frule vs_history, simp)
       
    57 by (erule deled_imp_childfs_deleted, simp+)
       
    58 
       
    59 lemma initf_deled_imp_childf_deled:
       
    60   "\<lbrakk>deleted (File f) s; valid s; f \<prec> childf; childf \<in> init_files\<rbrakk> 
       
    61   \<Longrightarrow> \<exists> s'. s' \<preceq> s \<and> valid s' \<and> deleted (File childf) s'"
       
    62 apply (drule deleted_has_del_event_file, simp, clarify)
       
    63 apply (frule vs_history, simp, frule valid_cons)
       
    64 apply (drule deled_imp_childfs_deleted, simp, simp)
       
    65 apply (rule_tac x = s' in exI, auto elim:no_juniorE)
       
    66 done
       
    67 
       
    68 lemma deleted_has_del_event_allchildf:
       
    69   "\<lbrakk>deleted (File f) s; valid s; f \<preceq> childf; childf \<in> init_files\<rbrakk>
       
    70   \<Longrightarrow> \<exists> s' p. DeleteFile p childf # s' \<preceq> s \<and> \<not> deleted (File childf) s'"
       
    71 apply (case_tac "f = childf")
       
    72 apply (drule deleted_has_del_event_file, simp, simp)
       
    73 apply (drule noJ_Anc'', simp)
       
    74 apply (drule initf_deled_imp_childf_deled, simp+, clarify)
       
    75 apply (drule deleted_has_del_event_file, simp+, clarify)
       
    76 apply (rule_tac x = s'a in exI, rule conjI, rule_tac x = p in exI)
       
    77 apply (erule no_junior_trans, simp+)
       
    78 done
       
    79 *)
       
    80 
       
    81 lemma del_imp_del_s_file:
       
    82   assumes initf: "f \<in> init_files"
       
    83   and deled: "deleted (File f) s"
       
    84   and vs: "valid s"
       
    85   shows "file_deletable_s f"
       
    86 proof -
       
    87   from deled vs obtain s' p' where
       
    88     his: "DeleteFile p' f # s' \<preceq> s" and fstdel: "\<not> deleted (File f) s'"
       
    89     by (drule_tac deleted_has_del_event_file, auto)
       
    90   from his vs have "valid (DeleteFile p' f # s')" by (simp add:vs_history)
       
    91   hence exp': "p' \<in> current_procs s'" and exf: "f \<in> current_files s'"
       
    92     and rc: "rc_grant s' (DeleteFile p' f)" and vs': "valid s'"
       
    93     by (auto dest:valid_os valid_rc valid_cons)
       
    94 
       
    95   from initf obtain t where etype: "etype_of_file [] f = Some t"
       
    96     by (drule_tac init_file_has_etype, simp add:etype_of_file_def, blast)
       
    97   from initf have sd: "source_dir [] f = Some f"
       
    98     by (simp add:source_dir_of_init') 
       
    99   hence "obj2sobj [] (File f) = SFile (t, f) (Some f)"
       
   100     using etype initf by (auto simp:obj2sobj.simps)
       
   101   with fstdel vs' initf exf etype
       
   102   have SF: "obj2sobj s' (File f) = SFile (t, f) (Some f)"
       
   103     using obj2sobj_file_remains'''[where s = "[]" and s' = s']
       
   104     by (auto simp:obj2sobj.simps)
       
   105 
       
   106   from exp' vs' obtain r' fr' pt' u' srp' where
       
   107     SP': "obj2sobj s' (Proc p') = SProc (r',fr',pt',u') srp'"
       
   108     by (frule_tac current_proc_has_sobj, simp, blast)
       
   109   with exp' vs' all_sobjs_I[where s = s' and obj = "Proc p'"]
       
   110   have SP'_in: "SProc (r',fr',pt',u') srp' \<in> all_sobjs" by simp
       
   111 
       
   112   show ?thesis unfolding file_deletable_s_def
       
   113     apply (rule_tac x = t in exI, 
       
   114            rule_tac x = "(r',fr',pt',u')" in exI,
       
   115            rule_tac x = srp' in exI)
       
   116     apply (simp add:SP'_in) 
       
   117     using rc SP' SF etype
       
   118     by (auto simp:obj2sobj.simps cp2sproc.simps split:option.splits if_splits)
       
   119 qed
       
   120 
       
   121 lemma del_imp_del_s_proc:
       
   122   assumes initp: "p \<in> init_processes"
       
   123   and deled: "deleted (Proc p) s"
       
   124   and vs: "valid s"
       
   125   shows "proc_deletable_s p"
       
   126 proof-
       
   127   from deled vs obtain s' p' where
       
   128     his: "Kill p' p # s' \<preceq> s" and fstdel: "\<not> deleted (Proc p) s'"
       
   129     by (drule_tac deleted_has_del_event_proc, auto)
       
   130   from his vs have "valid (Kill p' p # s')" by (simp add:vs_history)
       
   131   hence exp': "p' \<in> current_procs s'" and exp: "p \<in> current_procs s'"
       
   132     and rc: "rc_grant s' (Kill p' p)" and vs': "valid s'"
       
   133     by (auto dest:valid_os valid_rc valid_cons)
       
   134 
       
   135   from initp fstdel vs' have "source_proc s' p = Some p"
       
   136     apply (induct s', simp)
       
   137     apply (frule valid_cons, frule valid_os, frule not_deleted_cons_D, simp)
       
   138     by (case_tac a, auto dest:not_deleted_imp_exists simp:np_notin_curp)
       
   139   with exp initp vs' obtain r fr pt u 
       
   140     where SP: "obj2sobj s' (Proc p) = SProc (r,fr,pt,u) (Some p)"
       
   141     apply (frule_tac current_proc_has_sobj, simp)
       
   142     by (simp add:obj2sobj.simps split:option.splits, blast)
       
   143   with exp vs' all_sobjs_I[where s = s' and obj = "Proc p"]
       
   144   have SP_in: "SProc (r,fr,pt,u) (Some p) \<in> all_sobjs" by simp
       
   145 
       
   146   from exp' vs' obtain r' fr' pt' u' srp' where
       
   147     SP': "obj2sobj s' (Proc p') = SProc (r',fr',pt',u') srp'"
       
   148     by (frule_tac current_proc_has_sobj, simp, blast)
       
   149   with exp' vs' all_sobjs_I[where s = s' and obj = "Proc p'"]
       
   150   have SP'_in: "SProc (r',fr',pt',u') srp' \<in> all_sobjs" by simp
       
   151 
       
   152   show ?thesis unfolding proc_deletable_s_def
       
   153     apply (rule_tac x = r in exI, rule_tac x = fr in exI,
       
   154            rule_tac x = pt in exI, rule_tac x = u in exI,
       
   155            rule_tac x = "(r',fr',pt',u')" in exI,
       
   156            rule_tac x = srp' in exI)
       
   157     apply (simp add:SP_in SP'_in) 
       
   158     using rc SP SP'
       
   159     by (auto simp:obj2sobj.simps cp2sproc.simps split:option.splits)
       
   160 qed
       
   161     
       
   162 lemma del_imp_del_s_ipc:
       
   163   assumes initi: "i \<in> init_ipcs"
       
   164   and deled: "deleted (IPC i) s"
       
   165   and vs: "valid s"
       
   166   shows "ipc_deletable_s i"
       
   167 proof-
       
   168   from deled vs obtain s' p' where
       
   169     his: "DeleteIPC p' i # s' \<preceq> s" and fstdel: "\<not> deleted (IPC i) s'"
       
   170     by (drule_tac deleted_has_del_event_ipc, auto)
       
   171   from his vs have "valid (DeleteIPC p' i # s')" by (simp add:vs_history)
       
   172   hence exp': "p' \<in> current_procs s'" and exi: "i \<in> current_ipcs s'"
       
   173     and rc: "rc_grant s' (DeleteIPC p' i)" and vs': "valid s'"
       
   174     by (auto dest:valid_os valid_rc valid_cons)
       
   175 
       
   176   from initi obtain t where type: "init_ipc_type i = Some t" 
       
   177     using init_ipc_has_type by (auto simp:bidirect_in_init_def)
       
   178   with fstdel vs' initi exi have SI: "obj2sobj s' (IPC i) = SIPC t (Some i)"
       
   179     using obj2sobj_ipc_remains'''[where s = "[]" and s' = s']
       
   180     by (auto simp:obj2sobj.simps)
       
   181 
       
   182   from exp' vs' obtain r' fr' pt' u' srp' where
       
   183     SP': "obj2sobj s' (Proc p') = SProc (r',fr',pt',u') srp'"
       
   184     by (frule_tac current_proc_has_sobj, simp, blast)
       
   185   with exp' vs' all_sobjs_I[where s = s' and obj = "Proc p'"]
       
   186   have SP'_in: "SProc (r',fr',pt',u') srp' \<in> all_sobjs" by simp
       
   187 
       
   188   show ?thesis unfolding ipc_deletable_s_def
       
   189     apply (rule_tac x = t in exI, 
       
   190            rule_tac x = "(r',fr',pt',u')" in exI,
       
   191            rule_tac x = srp' in exI)
       
   192     apply (simp add: SP'_in) 
       
   193     using rc SP' SI type
       
   194     by (auto simp:obj2sobj.simps cp2sproc.simps split:option.splits if_splits)
       
   195 qed
       
   196 
       
   197 lemma deleted_imp_deletable_s:
       
   198   "\<lbrakk>deleted obj s; exists [] obj; valid s\<rbrakk> \<Longrightarrow> deletable_s obj"
       
   199 apply (case_tac obj)  
       
   200 apply (simp add:del_imp_del_s_proc)  
       
   201 apply (simp add:del_imp_del_s_file) 
       
   202 apply (simp add:del_imp_del_s_ipc)
       
   203 done
       
   204 
       
   205 (*
       
   206 lemma all_sobjs_E3:
       
   207   assumes prem: "sobj \<in> all_sobjs" 
       
   208   shows "\<exists> s obj. valid s \<and> obj2sobj s obj = sobj \<and> sobj_source_eq_obj sobj obj \<and> 
       
   209                   initp_intact_but s sobj \<and> exists s obj \<and> no_del_event s"
       
   210 proof-
       
   211   obtain t where "etype_of_file [] [] = Some t" 
       
   212     using root_in_filesystem current_file_has_etype[of "[]" "[]"] vs_nil 
       
   213     by auto
       
   214   with root_in_filesystem
       
   215   have "obj2sobj [] (File []) = SFile (t,[]) (Some [])"
       
   216     by (auto simp:obj2sobj.simps source_dir_of_init' 
       
   217             split:option.splits if_splits)
       
   218   moreover have "initp_intact []"
       
   219     by (auto simp:initp_intact_def cp2sproc.simps obj2sobj.simps 
       
   220             split:option.splits)
       
   221   ultimately show ?thesis
       
   222     using prem vs_nil root_in_filesystem 
       
   223     apply (drule_tac s' = "[]" and obj' = "File []" in all_sobjs_E2)
       
   224     apply (simp+, (erule exE|erule conjE)+)
       
   225     by (rule_tac x = s in exI, simp, rule_tac x = obj in exI, simp+)
       
   226 qed
       
   227 
       
   228 lemma del_s_imp_del_proc:
       
   229   assumes initp: "p \<in> init_processes"
       
   230   and del_s: "proc_deletable_s p"
       
   231   shows "\<exists> s. valid s \<and> deleted (Proc p) s"
       
   232 proof-
       
   233   from del_s obtain r fr pt u sp' srp' 
       
   234     where Target: "SProc (r,fr,pt,u) (Some p) \<in> all_sobjs" 
       
   235     and Killer: "SProc sp' srp' \<in> all_sobjs"
       
   236     and rc: "(role_of_sproc sp', Proc_type pt, DELETE) \<in> compatible"
       
   237     using proc_deletable_s_def by auto
       
   238   
       
   239   from Target obtain s where vs: "valid s" 
       
   240     and "obj2sobj s (Proc p) = SProc (r,fr,pt,u) (Some p)" 
       
   241     and "exists s (Proc p)"  and "no_del_event s"
       
   242     and "initp_intact_but s (SProc (r,fr,pt,u) (Some p))"
       
   243     apply (drule_tac all_sobjs_E3, clarsimp)
       
   244     by (frule obj2sobj_proc, clarsimp)
       
   245   with Killer obtain s' p' where vs': "valid (s' @ s)" and
       
   246     SP : "obj2sobj (s' @ s) (Proc p) = SProc (r,fr,pt,u) (Some p)" and
       
   247     exp: "exists (s' @ s) (Proc p)"  and
       
   248     SP': "obj2sobj (s' @ s) (Proc p') = SProc sp' srp'" and
       
   249     exp': "exists (s' @ s) (Proc p')"
       
   250     apply (drule_tac obj' = "Proc p" and s' = s in all_sobjs_E1, auto)
       
   251     apply (frule_tac obj = obj in obj2sobj_proc, erule exE)
       
   252     apply (auto intro:nodel_exists_remains)
       
   253     apply blast
       
   254     apply (frule_tac obj = "Proc p" in nodel_exists_remains)
       
   255 
       
   256 
       
   257 lemma deletable_s_imp_deleted:
       
   258   "deletable_s obj \<Longrightarrow> \<exists> s. valid s \<and> deleted obj s"
       
   259 apply (case_tac obj)
       
   260 apply (simp add:deletable_s.simps)
       
   261 
       
   262 
       
   263 lemma valid_kill_imp_proc_del_s:
       
   264   "\<lbrakk>valid (Kill p' p # s); p \<in> init_processes; \<not> deleted (Proc p) s\<rbrakk> \<Longrightarrow> proc_deletable_s p"
       
   265 apply (frule valid_os, frule valid_
       
   266 
       
   267 
       
   268 lemma build_phase: "f \<in> init_files \<and> file_deletable_s f \<longrightarrow> (\<exists> s. \<forall> childf. valids s \<and> f \<preceq> childf \<and> childf \<in> init_files \<and> etype_of_file [] f = Some t \<longrightarrow> (\<exists> p. p \<in> current_procs s \<and> currentrole s p = Some r \<and> (r, File_type t, DELETE) \<in> compatible))"
       
   269  thm all_sobjs_E0
       
   270 
       
   271 lemma del_phase: "f \<in> init_files \<and> file_deletable_s f \<and> (\<forall> childf. f \<preceq> childf \<and> childf \<notin> current_files s \<and> valid s"
       
   272 
       
   273 *)
       
   274 
       
   275 end
       
   276 
       
   277 end