util/sidparse: add cli SID utility

2 files changed, 140 insertions, 0 deletions

diff --git a/_oasis b/_oasis
index e552a3e..c7b8696 100644
--- a/_oasis
+++ b/_oasis
@@ -25,3 +25,8 @@ Test "test_sid"
   TestTools:       sid_test
   Command:         $sid_test
 
+Executable "sidparse"
+  Path:            util
+  MainIs:          sidparse.ml
+  BuildDepends:    sid, stdint, cmdliner, unix
+
diff --git a/util/sidparse.ml b/util/sidparse.ml
new file mode 100644
index 0000000..e99d27f
--- /dev/null
+++ b/util/sidparse.ml
@@ -0,0 +1,135 @@
+let err q v =
+  match q, v with
+    | true, _ -> Printf.ifprintf stdout
+    | _       -> Printf.eprintf
+and out q v =
+  match q, v with
+    | true, _
+    | _, true -> Printf.ifprintf stdout
+    | _       -> Printf.printf
+
+let header q v =
+  out q v "SID                            \
+           IDAUTH          \
+           NSUB SUBAUTHS\n%!"
+
+let emit q v s =
+  let ss = Sid.to_string s
+  and ia = Sid.get_ident_auth s
+  and sas = Sid.get_sub_auths s in
+  out q v "%-30s %-15s %-4d %s\n"
+    ss
+    (Stdint.Uint64.to_string ia)
+    (Array.length sas)
+    (Array.map Stdint.Uint32.to_string sas
+     |> Array.to_list
+     |> String.concat " ")
+
+let handle_input q v s =
+  match String.trim s with
+    | "" -> `Nothing
+    | s ->
+      try `Done (Sid.of_string s)
+      with Invalid_argument e -> err q v "ERROR: %s\n%!" e; `Junk
+
+let from_argv sids =
+  let rest = ref sids in
+  let next () =
+    match !rest with
+      | [] -> `Done
+      | hd::tl ->
+        rest := tl;
+        `Sid hd
+  in
+  next
+
+let from_stdin () =
+  try `Sid (input_line stdin)
+  with End_of_file -> `Done
+
+let traverse q v next =
+  let rec aux n ne =
+    match next () with
+      | `Done -> if ne = 0 then Ok n else Error (n, ne)
+      | `Sid s -> begin
+          match handle_input q v s with
+            | `Nothing -> aux n ne
+            | `Junk -> aux (n + 1) (ne + 1)
+            | `Done s -> begin
+                if n = 0 then header q v;
+                emit q v s;
+                aux (n + 1) ne
+              end
+        end
+  in
+  aux 0 0
+
+let sidparse validate quiet args =
+  let next =
+    match args with
+      | [] -> begin
+          if Unix.(isatty stdin) then
+            err quiet validate "reading input from stdin\n%!";
+          from_stdin
+        end
+      | sids -> from_argv sids
+  in
+  match traverse quiet validate next with
+    | Ok _ -> 0
+    | Error (n, ne) ->
+      if not quiet then
+        err quiet validate "processed %d items with %d errors\n" n ne;
+      -1
+
+open Cmdliner
+
+let arg_validate =
+  let doc = "Do not print table of constituent parts, only error messages." in
+  Arg.(value & flag & info ["v"; "validate"] ~doc)
+
+let arg_quiet =
+  let doc = "Do not print anything at all." in
+  Arg.(value & flag & info ["q"; "quiet"] ~doc)
+
+let arg_sid =
+  let doc = "Inputs specified on command line as positional arguments." in
+  Arg.(value & (pos_all string []) & info [] ~docv:"SID" ~doc)
+
+let cmd_sidparse =
+  let exits = Term.exit_info ~doc:"errors occurred" (-1) :: Term.default_exits in
+  let doc = "Process Windows security identifiers." in
+  let man =
+    [ `P "This command will parse SIDs (security identifiers) \
+          from the command line and standard input."
+    ; `P "The input is expected to consist of one SID per argument or \
+          line, respectively, in “string format” (cf. [MS-DTYP] 2.4.21)."
+    ; `S Manpage.s_see_also
+    ; `P "Consult Microsoft’s documentation for more information. \
+          SIDs are specified in MS-DTYP \
+          (https://msdn.microsoft.com/en-us/library/cc230273.aspx) \
+          with references to the Open Group RPC standard \
+          (http://www.opengroup.org/dce/download/)."
+    ; `S Manpage.s_examples
+    ; `P "Parse a number of SIDs supplied on command line:"
+    ; `Pre "$ sidparse S-1-0 S-1-1\n\
+            SID                           IDAUTH         NSUB SUBAUTHS\n\
+            S-1-0                         0              0\n\
+            S-1-1                         1              0\n"
+    ; `P "Parse a number of SIDs from standard input:"
+    ; `Pre "$ sidparse <<THATSALL\n\
+            S-1-0\n\
+            S-1-42-1337-2187\n\
+            THATSALL\n\
+            SID                            IDAUTH          NSUB SUBAUTHS\n\
+            S-1-0                          0               0    \n\
+            S-1-42-1337-2187               42              2    1337 2187"
+    ]
+  in
+  Term.(const sidparse $ arg_validate $ arg_quiet $ arg_sid),
+  Term.info ~doc ~man ~exits "sidparse"
+
+let () =
+  Term.eval (cmd_sidparse)
+  |> Term.exit_status
+;;
+