Source file exec.ml
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open Options
open Types
module type EXTENSION = sig
type path
and state
val initialization_callback : (path -> state -> state) option
val declaration_callback :
(Ast.t -> Script.env -> path -> state -> state option) option
val instruction_callback :
(Ast.Instr.t -> Script.env -> Ir.fallthrough list) option
val process_callback :
((module Ir.GRAPH with type t = 'a) -> 'a -> unit) option
val builtin_callback :
(Ir.builtin ->
(Virtual_address.t ->
path ->
int ->
state ->
(state, Types.status) Result.t)
option)
option
val builtin_printer : (Format.formatter -> Ir.builtin -> bool) option
val at_exit_callback : (unit -> unit) option
end
module type PLUGIN = sig
val name : string
val grammar_extension :
( unit,
Libparser.obj,
unit,
unit,
Libparser.obj Dyp.dyplexbuf )
Dyp.dyp_action
list
val instruction_printer : (Format.formatter -> Ast.Instr.t -> bool) option
val declaration_printer : (Format.formatter -> Ast.t -> bool) option
val extension :
(module Types.EXPLORATION_STATISTICS) ->
(module Path.S with type t = 'a) ->
(module Types.STATE with type t = 'b) ->
(module EXTENSION with type path = 'a and type state = 'b) option
end
let plugins = S.Htbl.create 8
let register_plugin (plugin : (module PLUGIN)) =
let module P = (val plugin) in
if S.Htbl.mem plugins P.name then
Options.Logger.fatal "plugin name %s has already been registered" P.name;
S.Htbl.add plugins P.name plugin
exception Halt
module OMap = Map.Make (struct
type t = string
let compare =
let rec iter s s' i =
let d =
Char.code (String.unsafe_get s i) - Char.code (String.unsafe_get s' i)
in
if d = 0 && i > 0 then iter s s' (i - 1) else d
in
fun s s' -> iter s s' (min (String.length s) (String.length s') - 1)
end)
let pp_value_as (format : Output.format) ppf bv =
match format with
| Bin -> Format.pp_print_string ppf @@ Bitvector.to_bitstring bv
| Dec -> Z.pp_print ppf @@ Bitvector.signed_of bv
| Hex -> Format.pp_print_string ppf @@ Bitvector.to_hexstring bv
| Ascii -> Format.fprintf ppf "%S" @@ Bitvector.to_asciistring bv
let same_symbol name attr ((expr : Ast.Expr.t), _) =
match expr with
| Symbol ((name', attr'), _) -> name = name' && attr = attr'
| _ -> false
module Func : sig
type t
val create : unit -> t
val add : t -> Virtual_address.t -> string -> int -> unit
val find : t -> Virtual_address.t -> (string * int) option
end = struct
module Range = struct
type t = Virtual_address.t * int * string * Virtual_address.t
let equal = ( = )
let len (_, len, _, _) = len
let crop ~lo ~hi (cur, _, name, base) =
(Virtual_address.add_int lo cur, hi - lo + 1, name, base)
let concat _ _ = assert false
end
module Map = Lmap.Make (Range)
type t = Map.t ref
let create () = ref Map.empty
let add tbl addr name size =
tbl :=
Map.store (Virtual_address.to_bigint addr) (addr, size, name, addr) !tbl
let find tbl addr =
match
Map.select
(fun _ _ -> raise_notrace Not_found)
(Virtual_address.to_bigint addr)
1 !tbl
with
| exception Not_found -> None
| cur, _, name, base -> Some (name, Virtual_address.diff cur base)
end
let invalid_fallthrough =
[ ("", [ Script.Error "Invalid replacement fallthrough" ]) ]
module Run (SF : STATE_FACTORY) (W : WORKLIST) () = struct
module Exploration_stats = Stats.Exploration ()
module Query_stats = Stats.Query ()
module Screen = Screen.Make (Exploration_stats) (Query_stats)
module Path = Path.Make ()
module State : STATE = struct
include SF (Query_stats)
let id =
Path.register_key Uid.zero ~merge:(fun id id' ->
if Uid.compare id id' >= 0 then Some id else Some id')
let symbols = Path.register_key S.Map.empty
end
module Dcode = Dcode.Make (Exploration_stats) (Path) (State)
module Fiber = Dcode.Fiber
module Eval = Eval.Make (Path) (State)
type fiber = [ `All ] Fiber.t
and thunk = {
path : Path.t;
depth : int;
ip : Virtual_address.t;
fiber : fiber;
state : State.t;
}
and 'a mode =
| Default : unit mode
| Linear : State.t mode
| Merge : thunk mode
type section =
| RX of { base : Virtual_address.t; size : int; content : Loader_buf.t }
| RWX
type t = {
mutable code : section Imap.t; (** set of executable sections *)
rocache : fiber Virtual_address.Htbl.t;
(** instruction cache for RX sections *)
cache : fiber OMap.t Virtual_address.Htbl.t;
(** instruction cache for RWX sections *)
mutable worklist : thunk W.t; (** worklist of pending path *)
mutable tid : int; (** the next unique task identifier *)
tasks : unit I.Htbl.t; (** set of tasks to perform *)
mutable dcode : Dcode.t option Imap.t;
mutable whooks :
((string * Script.Instr.t list) list * Script.env) Virtual_address.Map.t;
endianness : Machine.endianness;
}
let env : t =
let img = Kernel_functions.get_img () in
let transient = TransientEnum.get () > 0 in
let rocache_size, _cache_size, code =
Array.fold_left
(fun (rocache, cache, code) s ->
if Loader.Section.has_flag Loader_types.Exec s then
let { Loader_types.virt = pos; _ } = Loader.Section.pos s in
let { Loader_types.virt = size; _ } = Loader.Section.size s in
let rodelta, delta, section =
if Loader.Section.has_flag Loader_types.Write s then
if transient then (
Logger.debug ~level:4
"Section %S [%a, 0x%x] has both Write and Execute flags."
(Loader.Section.name s) Virtual_address.pp
(Virtual_address.create pos)
size;
(0, size, RWX))
else (
Logger.warning
"Section %S [%a, 0x%x] has both Write and Execute flags.@ \
Self-modifying code is disabled and writes will be \
ignored.@ Use '-sse-self-written-enum N' to enable \
symbolic reasoning up to 'N - 1' forks."
(Loader.Section.name s) Virtual_address.pp
(Virtual_address.create pos)
size;
( size,
0,
RX
{
base = Virtual_address.create pos;
size;
content = Loader.Img.content img s;
} ))
else
( size,
0,
RX
{
base = Virtual_address.create pos;
size;
content = Loader.Img.content img s;
} )
in
( rocache + rodelta,
cache + delta,
Imap.add ~base:(Z.of_int pos) size section code )
else (rocache, cache, code))
(0, 0, Imap.empty) (Loader.Img.sections img)
in
let arrays = S.Htbl.create 7 in
S.Htbl.add arrays "@" A.default;
{
code;
rocache = Virtual_address.Htbl.create rocache_size;
cache = Virtual_address.Htbl.create 0 ;
worklist = W.empty;
tid = 0;
tasks = I.Htbl.create 7;
dcode = Imap.empty;
whooks = Virtual_address.Map.empty;
endianness = Kernel_options.Machine.endianness ();
}
let hook_anchors = Virtual_address.Htbl.create 4
let pp_virtual_address ppf addr =
Virtual_address.pp ppf addr;
try
let anchor = Virtual_address.Htbl.find hook_anchors addr in
Format.fprintf ppf " (%s)" anchor
with Not_found -> ()
let choose () =
try
let thunk, worklist = W.pop env.worklist in
Logger.debug ~level:3 "Selecting path #%d (among %d)" (Path.id thunk.path)
(Exploration_stats.get_pending_paths ());
env.worklist <- worklist;
thunk
with Not_found ->
Logger.info "Empty path worklist: halting ...";
raise_notrace Halt
let add path = env.worklist <- W.push path env.worklist
let at_exit_callbacks = Queue.create ()
let threat_to_completeness () =
let max_depth = Exploration_stats.get_status Max_depth in
let incomplete_enum = Exploration_stats.get_status Enumeration_limit in
let unknown = Exploration_stats.get_status Unresolved_formula in
if max_depth + incomplete_enum + unknown > 0 then
Logger.warning "@[<v>Threat to completeness :%a@]"
(fun ppf (max_depth, incomplete_enum, unknown) ->
if max_depth > 0 then
Format.fprintf ppf
"@ - %d paths have reached the maximal depth and have been cut \
(-sse-depth)"
max_depth;
if incomplete_enum > 0 then
Format.fprintf ppf
"@ - some jump targets may have been omitted (-sse-jump-enum)";
if unknown > 0 then
Format.fprintf ppf
"@ - %d SMT solver queries remain unsolved (-fml-solver-timeout)"
unknown)
(max_depth, incomplete_enum, unknown)
let halt () =
Screen.release ();
Logger.info "@[<v 0>@[<v 2>SMT queries@,%a@]@,@[<v 2>Exploration@,%a@]@,@]"
Query_stats.pp () Exploration_stats.pp ();
threat_to_completeness ();
Queue.iter (fun callback -> callback ()) at_exit_callbacks
let ascii_stream name path state =
let buf = Buffer.create 16 in
List.iter (fun elt ->
let rec iter bv =
let size = Bitvector.size_of bv in
assert (size mod 8 = 0);
if size = 8 then Buffer.add_char buf (Bitvector.to_char bv)
else
let byte = Bitvector.extract bv { Interval.lo = 0; hi = 7 } in
Buffer.add_char buf (Bitvector.to_char byte);
iter (Bitvector.extract bv { Interval.lo = 8; hi = size - 1 })
in
iter (State.get_a_value elt state))
@@ List.rev
@@ S.Map.find name (Path.get State.symbols path);
Buffer.contents buf
let c_string array state =
try
let buf = Buffer.create 16 in
let rec iter addr =
let byte =
State.get_a_value
(Eval.eval
(Expr.load ~array Size.Byte.one Machine.LittleEndian
(Expr.constant addr))
state)
state
in
if Bitvector.is_zeros byte then Buffer.contents buf
else (
Buffer.add_char buf (Bitvector.to_char byte);
iter (Bitvector.succ addr))
in
iter (Bitvector.zeros (Kernel_options.Machine.word_size ()))
with Uninterp _ -> ""
let print addr path state (output : Output.t) =
match output with
| Model ->
Logger.result "@[<v 0>Model %@ %a@ %a@]" pp_virtual_address addr
State.pp state
| Formula ->
Logger.result "Formula %@ %a@\n%a" pp_virtual_address addr
(State.pp_smt None) state
| Slice slice ->
let slice =
let rec proceed slice state =
try
List.map (fun (expr, name) -> (Eval.eval expr state, name)) slice
with
| Undef var -> proceed slice (Eval.fresh var state path)
| Uninterp array -> proceed slice (State.alloc ~array state)
in
proceed slice state
in
Logger.result "Formula for %a %@ %a@\n%a" pp_virtual_address addr
(Format.pp_print_list ~pp_sep:Format.pp_print_space (fun ppf (_, n) ->
Format.pp_print_string ppf n))
slice
(State.pp_smt (Some slice))
state
| Value (format, e) ->
Logger.result "@[<v 0>Value %a : %a@]" Dba_printer.Ascii.pp_bl_term e
(pp_value_as format)
(fst (List.hd (Eval.split_on ~n:1 e state path)))
| Stream name ->
Logger.result "@[<v 0>Ascii stream %s : %S@]" name
(ascii_stream name path state)
| String name ->
Logger.result "@[<v 0>C string %s : %S@]" name (c_string name state)
let rec exec :
type a.
a mode ->
Path.t ->
int ->
max_depth:int ->
State.t ->
Virtual_address.t ->
fiber ->
a =
fun mode path depth ~max_depth state ip fiber ->
match fiber with
| Debug { msg; succ } ->
Logger.debug "%s" msg;
exec mode path depth ~max_depth state ip succ
| Print { output; succ } ->
print ip path state output;
exec mode path depth ~max_depth state ip succ
| Step { addr; n; succ } -> (
let depth = depth + n in
Exploration_stats.add_instructions n;
Exploration_stats.update_depth depth;
if depth <= max_depth then
exec mode path depth ~max_depth state addr succ
else
match mode with
| Default ->
Logger.warning "@[<hov>Cut path %d (max depth) %@ %a@]"
(Path.id path) Virtual_address.pp addr;
Exploration_stats.terminate_path Max_depth;
Path.terminate path Max_depth;
yield Default ~max_depth
| Linear -> state
| Merge -> { path; depth; ip; state; fiber })
| Symbolize { var; succ } ->
exec mode path depth ~max_depth (Eval.fresh var state path) ip succ
| Assign { var; rval; succ } ->
exec mode path depth ~max_depth
(Eval.assign var rval state path)
ip succ
| Clobber { var = { name; size; _ } as var; succ } ->
Logger.warning ~level:3
"path %d undefined variable %S arbitrarily set to zeros %@ %a"
(Path.id path) name Virtual_address.pp ip;
exec mode path depth ~max_depth
(Eval.assign var (Dba.Expr.zeros size) state path)
ip succ
| Load { var; base = None; dir; addr; succ } ->
let rval, state = Eval.read ~addr (var.size / 8) dir state path in
exec mode path depth ~max_depth (State.assign var rval state) ip succ
| Store { base = None; dir; addr; rval; succ } ->
exec mode path depth ~max_depth
(Eval.write ~addr rval dir state path)
ip succ
| Load { var; base = Some name; dir; addr; succ } ->
let rval, state =
Eval.select name ~addr (var.size / 8) dir state path
in
exec mode path depth ~max_depth (State.assign var rval state) ip succ
| Store { base = Some name; dir; addr; rval; succ } ->
exec mode path depth ~max_depth
(Eval.store name ~addr rval dir state path)
ip succ
| Assume _ as fiber -> assume mode path depth ~max_depth state ip fiber
| Assert _ as fiber -> check mode path depth ~max_depth state ip fiber
| Branch _ as fiber -> ite mode path depth ~max_depth state ip fiber
| Goto addr -> goto mode path depth ~max_depth state ip addr fiber
| Jump _ as fiber -> dynamic_jump mode path depth ~max_depth state ip fiber
| Probe _ as fiber -> probe mode path depth ~max_depth state ip fiber
| Builtin { f; succ } -> (
match f ip path depth state with
| Error status ->
Exploration_stats.terminate_path status;
Path.terminate path status;
if status = Halt then raise Halt;
yield mode ~max_depth
| Ok state -> exec mode path depth ~max_depth state ip succ)
| Cut ->
Exploration_stats.terminate_path Cut;
Path.terminate path Cut;
Logger.debug ~level:0 "@[<hov>Cut path %d (directive) %@ %a@]"
(Path.id path) pp_virtual_address ip;
yield mode ~max_depth
| Halt -> (
match mode with
| Default ->
Exploration_stats.terminate_path Halt;
Path.terminate path Halt;
Logger.debug ~level:0 "@[<hov>End of path %d %@ %a@]" (Path.id path)
pp_virtual_address ip;
yield mode ~max_depth
| Linear -> state
| Merge -> { path; depth; ip; state; fiber })
| Die msg ->
Exploration_stats.terminate_path Die;
Path.terminate path Die;
Logger.error "@[<hov>Cut path %d (uninterpreted %S) %@ %a@]"
(Path.id path) msg pp_virtual_address ip;
yield mode ~max_depth
and assume :
type a.
a mode ->
Path.t ->
int ->
max_depth:int ->
State.t ->
Virtual_address.t ->
[ `Assume ] Fiber.t ->
a =
fun mode path depth ~max_depth state ip (Assume { test; succ } as fiber) ->
match mode with
| Merge -> (
match Eval.get_value test state path with
| exception Non_unique -> { path; depth; ip; state; fiber }
| x ->
if Bitvector.is_one x then
exec mode path depth ~max_depth state ip succ
else { path; depth; ip; state; fiber = Cut })
| Linear | Default -> (
match Eval.assume test state path with
| exception Unknown ->
Exploration_stats.terminate_path Unresolved_formula;
Path.terminate path Unresolved_formula;
yield mode ~max_depth
| None ->
Logger.warning
"@[<hov>Cut path %d (unsatisfiable assumption) %@ %a@]"
(Path.id path) pp_virtual_address ip;
Exploration_stats.terminate_path Unsatisfiable_assumption;
Path.terminate path Unsatisfiable_assumption;
yield mode ~max_depth
| Some state -> exec mode path depth ~max_depth state ip succ)
and check :
type a.
a mode ->
Path.t ->
int ->
max_depth:int ->
State.t ->
Virtual_address.t ->
[ `Assert ] Fiber.t ->
a =
fun mode path depth ~max_depth state ip (Assert { test; succ } as fiber) ->
match mode with
| Linear -> assert false
| Merge -> (
match Eval.get_value test state path with
| exception Non_unique -> { path; depth; ip; state; fiber }
| x ->
Exploration_stats.add_assert ();
if Bitvector.is_one x then
exec mode path depth ~max_depth state ip succ
else (
Logger.error "@[<v 2> Assertion failed %@ %a@ %a@]"
pp_virtual_address ip State.pp state;
Exploration_stats.add_failed_assert ();
{ path; depth; ip; state; fiber = Cut }))
| Default -> (
Exploration_stats.add_assert ();
match Eval.test test state path with
| exception Unknown ->
Exploration_stats.terminate_path Unresolved_formula;
Path.terminate path Unresolved_formula;
yield mode ~max_depth
| True state -> exec mode path depth ~max_depth state ip succ
| False state ->
Logger.error "@[<v 2> Assertion failed %@ %a@ %a@]"
pp_virtual_address ip State.pp state;
Exploration_stats.add_failed_assert ();
Exploration_stats.terminate_path Assertion_failed;
Path.terminate path Assertion_failed;
yield mode ~max_depth
| Both { t = state; f } ->
Logger.error "@[<v 2> Assertion failed %@ %a@ %a@]"
pp_virtual_address ip State.pp f;
Exploration_stats.add_failed_assert ();
exec mode path depth ~max_depth state ip succ)
and ite :
type a.
a mode ->
Path.t ->
int ->
max_depth:int ->
State.t ->
Virtual_address.t ->
[ `Branch ] Fiber.t ->
a =
fun mode path depth ~max_depth state ip
(Branch { test; taken; fallthrough; _ } as fiber) ->
Exploration_stats.add_branch ();
match mode with
| Linear -> assert false
| Merge -> (
match Eval.get_value test state path with
| exception Non_unique -> { path; depth; ip; state; fiber }
| x ->
exec Merge path depth ~max_depth state ip
(if Bitvector.is_one x then taken else fallthrough))
| Default -> (
let parent = state in
match Eval.test test state path with
| exception Unknown ->
Exploration_stats.terminate_path Unresolved_formula;
Path.terminate path Unresolved_formula;
yield mode ~max_depth
| True state ->
add { path; depth; ip; state; fiber = taken };
yield mode ~max_depth
| False state ->
add { path; depth; ip; state; fiber = fallthrough };
yield mode ~max_depth
| Both { t = state; f = state' } ->
let k = QMerge.get () in
if k > 0 then (
let path' = Path.fork path in
let taken =
exec Merge path depth ~max_depth:(depth + k) state ip taken
in
Path.set State.id (Path.get State.id path) path';
let fallthrough =
exec Merge path' depth ~max_depth:(depth + k) state' ip
fallthrough
in
if taken.ip == fallthrough.ip && taken.fiber == fallthrough.fiber
then
match Path.merge path path' with
| None ->
add taken;
Exploration_stats.add_path ();
add fallthrough;
yield mode ~max_depth
| Some path'' -> (
match State.merge ~parent taken.state fallthrough.state with
| exception Non_mergeable ->
add taken;
Exploration_stats.add_path ();
add fallthrough;
yield mode ~max_depth
| state ->
exec mode path''
(max taken.depth fallthrough.depth)
~max_depth state taken.ip taken.fiber)
else (
add taken;
Exploration_stats.add_path ();
add fallthrough;
yield mode ~max_depth))
else (
add { path; depth; ip; state; fiber = taken };
Exploration_stats.add_path ();
add
{
path = Path.fork path;
depth;
ip;
state = state';
fiber = fallthrough;
};
yield mode ~max_depth))
and dynamic_jump :
type a.
a mode ->
Path.t ->
int ->
max_depth:int ->
State.t ->
Virtual_address.t ->
[ `Jump ] Fiber.t ->
a =
fun mode path depth ~max_depth state ip (Jump target as fiber) ->
let n = JumpEnumDepth.get () in
let handle path depth ip addr (bv, state) =
try
Logger.debug ~level:4 "@[<hov>Dynamic jump@ %@%a@ could lead to@ %a@]"
Virtual_address.pp addr Bitvector.pp_hex_or_bin bv;
add
{
path;
depth;
ip;
fiber = Goto (Virtual_address.of_bitvector bv);
state;
}
with Virtual_address.Non_canonical_form ->
Logger.warning
"@[<hov>Dynamic jump %@ %a@ could have led to invalid address %a;@ \
skipping@]"
Virtual_address.pp addr Bitvector.pp_hex_or_bin bv;
Exploration_stats.terminate_path Die;
Path.terminate path Die
in
Exploration_stats.add_branch ();
match mode with
| Linear -> assert false
| Merge -> (
match Eval.get_value target state path with
| exception Non_unique -> { path; depth; ip; state; fiber }
| x ->
goto mode path depth ~max_depth state ip
(Virtual_address.of_bitvector x)
fiber)
| Default -> (
match Eval.split_on target ~n state path with
| [] | (exception Unknown) ->
Exploration_stats.terminate_path Unresolved_formula;
Path.terminate path Unresolved_formula;
yield mode ~max_depth
| [ (x, state) ] ->
goto mode path depth ~max_depth state ip
(Virtual_address.of_bitvector x)
fiber
| x :: bx ->
let old_paths = Exploration_stats.get_paths () in
let addr = ip in
handle path depth ip addr x;
List.iter
(fun x ->
Exploration_stats.add_path ();
handle (Path.fork path) depth ip addr x)
bx;
if Exploration_stats.get_paths () - old_paths = n - 1 then (
Logger.warning
"Enumeration of jump targets %@ %a hit the limit %d and may be \
incomplete"
Virtual_address.pp addr n;
Exploration_stats.add_path ();
Exploration_stats.terminate_path Enumeration_limit);
yield mode ~max_depth)
and goto :
type a.
a mode ->
Path.t ->
int ->
max_depth:int ->
State.t ->
Virtual_address.t ->
Virtual_address.t ->
fiber ->
a =
fun mode path depth ~max_depth state ip addr rollback ->
match Virtual_address.Htbl.find env.rocache addr with
| target -> exec mode path depth ~max_depth state ip target
| exception Not_found -> (
match Imap.find (Virtual_address.to_bigint addr) env.dcode with
| exception Not_found ->
Logger.warning "@[<hov>Cut path %d (non executable) %@ %a@]"
(Path.id path) Virtual_address.pp addr;
Exploration_stats.terminate_path Non_executable_code;
Path.terminate path Non_executable_code;
yield mode ~max_depth
| Some code ->
let fiber = Dcode.get code addr in
Virtual_address.Htbl.add env.rocache addr fiber;
exec mode path depth ~max_depth state ip fiber
| None -> (
match mode with
| Linear -> assert false
| Merge -> { path; depth; ip; state; fiber = rollback }
| Default ->
transient_instruction mode path depth ~max_depth state addr))
and transient_instruction :
type a.
a mode ->
Path.t ->
int ->
max_depth:int ->
State.t ->
Virtual_address.t ->
a =
fun mode path depth ~max_depth state addr ->
let n = TransientEnum.get () in
let hooks = Virtual_address.Map.find_opt addr env.whooks in
let handle path depth (omap : fiber OMap.t) addr (bv, state) =
let opcode = Bitvector.to_asciistring bv in
let omap, fiber =
try (omap, OMap.find opcode omap)
with Not_found ->
let reader = Lreader.of_bytes ~endianness:env.endianness opcode in
let scope, inst =
Dcode.single ~task:env.tasks ?hooks addr reader
(Bitvector.size_of bv / 8)
in
let omap =
match inst with
| None -> OMap.add "" scope omap
| Some inst ->
Logger.debug ~level:4
"@[<hov>Self-written instruction @@ %a could be %a [ %a ]@]"
Virtual_address.pp addr Mnemonic.pp
(Instruction.mnemonic inst)
String_utils.pp_hex opcode;
let s = (Instruction.size inst :> int) in
if s = 0 then omap
else OMap.add (String.sub opcode 0 s) scope omap
in
(omap, scope)
in
add { path; depth; ip = addr; state; fiber };
omap
in
let omap =
try Virtual_address.Htbl.find env.cache addr
with Not_found -> OMap.empty
in
let opcode =
Expr.load
(Isa_helper.max_instruction_len ())
env.endianness
(Expr.constant
(Bitvector.of_int
~size:(Kernel_options.Machine.word_size ())
(addr :> int)))
in
match Eval.split_on opcode ~n state path with
| [] | (exception Unknown) ->
Exploration_stats.terminate_path Unresolved_formula;
Path.terminate path Unresolved_formula;
yield mode ~max_depth
| x :: bx ->
let omap =
List.fold_left
(fun omap x ->
Exploration_stats.add_path ();
let omap = handle (Path.fork path) depth omap addr x in
omap)
omap bx
in
let omap = handle path depth omap addr x in
Virtual_address.Htbl.replace env.cache addr omap;
yield mode ~max_depth
and yield : type a. a mode -> max_depth:int -> a =
fun mode ~max_depth ->
let { path; depth; ip; fiber; state } = choose () in
exec mode path depth ~max_depth state ip fiber
and probe :
type a.
a mode ->
Path.t ->
int ->
max_depth:int ->
State.t ->
Virtual_address.t ->
[ `Probe ] Fiber.t ->
a =
fun mode path depth ~max_depth state ip (Probe { kind; succ } as fiber) ->
match kind with
| Enumerate ({ enum; id = tid; format; n; k; values } as e) ->
if n > k then (
let values' = Eval.split_on enum ~n ~except:values state path in
let values =
List.fold_left (fun values (bv, _) -> bv :: values) values values'
in
let k = List.length values in
Logger.result
"@[<hov 0>Directive :: enumerate@ possible values (%d) for %a %@ \
%a:@ @[<hov 0>%a@]@]"
k Dba_printer.Ascii.pp_bl_term enum pp_virtual_address ip
(Print_utils.pp_list ~sep:",@ " (pp_value_as format))
values;
e.k <- k;
e.values <- values;
if n = k then (
I.Htbl.remove env.tasks tid;
if I.Htbl.length env.tasks = 0 then raise_notrace Halt));
exec mode path depth ~max_depth state ip succ
| Reach { n = 0; _ } -> exec mode path depth ~max_depth state ip succ
| Reach ({ id = tid; n; guard; actions } as r) -> (
match mode with
| Linear -> assert false
| Merge -> { path; depth; ip; state; fiber }
| Default -> (
match Eval.assume guard state path with
| exception Unknown ->
Exploration_stats.terminate_path Unresolved_formula;
Path.terminate path Unresolved_formula;
yield mode ~max_depth
| None -> exec mode path depth ~max_depth state ip succ
| Some state' ->
let addr = ip in
Logger.result "@[<h>Path %d reached address %a (%a to go)@]"
(Path.id path) pp_virtual_address addr
(fun ppf n ->
if n = -1 then Format.pp_print_char ppf '*'
else Format.pp_print_int ppf (n - 1))
n;
List.iter (fun output -> print addr path state' output) actions;
if n > 0 then (
r.n <- n - 1;
if n = 1 then (
I.Htbl.remove env.tasks tid;
if I.Htbl.length env.tasks = 0 then raise_notrace Halt));
exec Default path depth ~max_depth state ip succ))
let initialize_state () =
let state = State.empty () in
let addr_size = Kernel_options.Machine.word_size ()
and img = Kernel_functions.get_img () in
let entry =
match Kernel_functions.get_ep () with
| Some addr -> addr
| None -> Virtual_address.create (Loader.Img.entry img)
in
let start = ref (Fiber.Goto entry) in
let prehooks = ref Virtual_address.Map.empty
and hooks = ref Virtual_address.Map.empty in
let symbols : (Dba.Var.Tag.attribute * Bitvector.t) S.Htbl.t =
S.Htbl.create 100
and shadowing_symbols : (string * string option) S.Htbl.t =
S.Htbl.create 100
and core_symbols : (Dba.Var.Tag.attribute * Bitvector.t) S.Htbl.t S.Htbl.t =
S.Htbl.create 1
in
let functions = Func.create () in
let return_instructions = S.Htbl.create 16 in
let parser_env =
let wordsize = Kernel_options.Machine.word_size () in
let tbl = S.Htbl.create 128 and ori = S.Htbl.create 128 in
List.iter
(fun (name, var) -> S.Htbl.add tbl (String.lowercase_ascii name) var)
(Isa_helper.get_defs ());
let define (var : Dba.Var.t) pos =
let name = String.lowercase_ascii var.name in
S.Htbl.add tbl name (Dba.LValue.v var);
if pos <> Lexing.dummy_pos then S.Htbl.add ori name pos
in
let origin name = S.Htbl.find_opt ori name in
let lookup name = S.Htbl.find tbl (String.lowercase_ascii name) in
let tbl = S.Htbl.create 128 in
let lookup_symbol name (attr : Dba.Var.Tag.attribute) =
try List.assoc attr (S.Htbl.find_all tbl name)
with Not_found ->
let value =
lazy
(try List.assoc attr (S.Htbl.find_all symbols name)
with Not_found -> raise (Unresolved (name, attr)))
in
(if S.Htbl.mem shadowing_symbols name then
let file, sec = S.Htbl.find shadowing_symbols name in
Logger.warning
"@[<v>Symbol %s comes from%a the file %s and shadows other \
definitions@ Use \"import <%s> from FILE\" to disambiguate"
name
(Format.pp_print_option (fun ppf sec ->
Format.fprintf ppf " a relocation in section %s of" sec))
sec file name);
let tag = Dba.Var.Tag.Symbol (attr, value) in
let sym = Dba.Expr.var ~tag name wordsize in
S.Htbl.add tbl name (attr, sym);
sym
in
Script.
{
wordsize;
endianness = Kernel_options.Machine.endianness ();
define;
origin;
lookup;
lookup_symbol;
}
in
(match img with
| ELF img -> (
let open Loader_elf in
Array.iter
(fun sym ->
match Symbol.header sym with
| { kind = SECTION as kind; sh = SEC { name; addr; size; _ }; _ }
| { sh = SEC _; name; value = addr; size; kind; _ }
when not (Utils.is_ifunc img sym) ->
S.Htbl.add symbols name
(Value, Bitvector.of_int ~size:addr_size addr);
S.Htbl.add symbols name
(Size, Bitvector.of_int ~size:addr_size size);
S.Htbl.add symbols name
(Last, Bitvector.of_int ~size:addr_size (addr + size - 1));
if kind = FUNC then
Func.add functions (Virtual_address.create addr) name size
| _ -> ())
(Img.symbols img);
Array.iter
(fun sec ->
let { Shdr.name; flags; addr; size; _ } = Section.header sec in
if Shdr.SHF.is flags ALLOC && not (S.Htbl.mem symbols name) then (
S.Htbl.add symbols name
(Value, Bitvector.of_int ~size:addr_size addr);
S.Htbl.add symbols name
(Size, Bitvector.of_int ~size:addr_size size);
S.Htbl.add symbols name
(Last, Bitvector.of_int ~size:addr_size (addr + size - 1))))
(Img.sections img);
match Img.header img with
| { Ehdr.kind = DYN; machine = X86 _; _ } ->
let rela_plt, base =
Array.fold_left
(fun ((rela_opt, base) as r) sec ->
let ({ Shdr.name; addr; _ } as ) = Section.header sec in
match name with
| ".rela.plt" -> (Some header, base)
| ".plt" when base = -1 -> (rela_opt, addr + 16)
| ".plt.sec" -> (rela_opt, addr)
| _ -> r)
(None, -1) (Img.sections img)
in
Option.iter
(fun rela_plt ->
Array.iteri
(fun i { Rel.symbol = { name; _ }; _ } ->
S.Htbl.add symbols name
(Plt, Bitvector.of_int ~size:addr_size (base + (16 * i))))
(Rel.read img rela_plt))
rela_plt
| _ -> ())
| _ ->
let open Loader in
Array.iter
(fun sym ->
S.Htbl.add symbols (Symbol.name sym)
(Value, Bitvector.of_int ~size:addr_size (Symbol.value sym)))
(Img.symbols img);
Array.iter
(fun sec ->
let name = Section.name sec in
let { Loader_types.virt = addr; _ } = Section.pos sec in
S.Htbl.add symbols name
(Value, Bitvector.of_int ~size:addr_size addr);
let { Loader_types.virt = size; _ } = Section.size sec in
S.Htbl.add symbols name (Size, Bitvector.of_int ~size:addr_size size);
S.Htbl.add symbols name
(Last, Bitvector.of_int ~size:addr_size (addr + size - 1)))
(Img.sections img));
let rec copy_from addr size state =
let section =
match
Loader_utils.find_section_by_address ~address:(Bitvector.to_int addr)
img
with
| None ->
Logger.fatal "address %a does not belong to file" Virtual_address.pp
(Virtual_address.of_bitvector addr)
| Some section -> section
in
let { Loader_types.virt; _ } = Loader.Section.size section in
if virt >= size then
State.memcpy ~addr size (Loader.Img.content img section) state
else
copy_from
(Bitvector.add_int addr virt)
(size - virt)
(State.memcpy ~addr virt (Loader.Img.content img section) state)
in
let set path state init =
let init =
Dcode.script ~task:env.tasks entry ~fallthrough:false init parser_env
in
exec Linear path 0 ~max_depth:max_int state entry init
in
let from_core path prehook state =
match Kernel_functions.get_img () with
| Loader.Raw _ | Loader.PE _ | Loader.TI83 _ ->
Logger.fatal "Binary is not an ELF file."
| Loader.ELF img' ->
let hdr = Loader_elf.Img.header img' in
if hdr.Loader_elf.Ehdr.kind <> Loader_elf.Ehdr.ET.CORE then
Logger.fatal "Binary is not a core file";
let vmap, state =
Array.fold_left
(fun (vmap, state) section ->
let open Loader_elf in
let hdr = Section.header section in
if Section.has_flag Loader_types.Read section then
let addr =
Bitvector.of_int
~size:(Kernel_options.Machine.word_size ())
hdr.Shdr.addr
in
( Imap.add ~base:(Bitvector.value_of addr) hdr.Shdr.size true
vmap,
State.memcpy ~addr hdr.Shdr.size (Img.content img' section)
state )
else (vmap, state))
(Imap.empty, state)
(Loader_elf.Img.sections img')
in
let transient = TransientEnum.get () > 0 in
let dyn_symbols = Queue.create () in
let _, _, xcode, state =
Array.fold_left
(fun (vmap, fmap, xcode, state)
{ Loader_elf.addresses = { lo; hi }; offset; name = fname } ->
if S.Set.mem fname fmap then (vmap, fmap, xcode, state)
else
match Loader.load_file fname with
| (Raw _ | PE _ | TI83 _) as img ->
let base = Virtual_address.to_bigint lo
and size = Virtual_address.diff hi lo + 1
and { Loader_buf.buffer; _ } = Loader.Img.cursor img in
let vmap = Imap.add ~base size true vmap in
let state =
State.memcpy
~addr:(Bitvector.create base addr_size)
size
(Bigarray.Array1.sub buffer offset
(min size (Bigarray.Array1.dim buffer - offset)))
state
in
(vmap, fmap, xcode, state)
| ELF img ->
let size = Virtual_address.diff hi lo + 1 in
let section =
Option.get
(Loader_utils.find_section
~p:(fun s ->
let { Loader_types.raw; _ } =
Loader.Section.pos s
in
Loader.Section.has_flag Loader_types.Read s
&& offset <= raw
&& raw < offset + size)
(Loader.ELF img))
in
let { Loader_types.raw; virt } =
Loader.Section.pos section
in
let base =
Virtual_address.diff
(Virtual_address.add_int (raw - offset) lo)
(Virtual_address.create virt)
in
Logger.debug "%08x :: %a-%a %08x %s" base
Virtual_address.pp lo Virtual_address.pp hi offset fname;
let private_symbols :
(Dba.Var.Tag.attribute * Bitvector.t) S.Htbl.t =
S.Htbl.create 100
in
Array.iter
(fun sym ->
match Loader_elf.Symbol.header sym with
| {
kind = SECTION as kind;
sh = SEC { name; addr; size; _ };
_;
}
| { sh = SEC _; name; value = addr; size; kind; _ }
when not (Loader_elf.Utils.is_ifunc img sym) ->
if kind = FUNC then
Func.add functions
(Virtual_address.create (base + addr))
name size;
if S.Htbl.mem symbols name then (
S.Htbl.remove symbols name;
S.Htbl.replace shadowing_symbols name
(fname, None));
let value =
( Dba.Var.Tag.Value,
Bitvector.of_int ~size:addr_size (base + addr)
)
in
S.Htbl.add private_symbols name value;
S.Htbl.add symbols name value;
let last =
( Dba.Var.Tag.Last,
Bitvector.of_int ~size:addr_size
(base + addr + size - 1) )
in
S.Htbl.add private_symbols name last;
S.Htbl.add symbols name last;
let size =
( Dba.Var.Tag.Size,
Bitvector.of_int ~size:addr_size size )
in
S.Htbl.add private_symbols name size;
S.Htbl.add symbols name size
| _ -> ())
(Loader_elf.Img.symbols img);
Array.iter
(fun section ->
let name = Loader_elf.Section.name section
and { Loader_types.virt = addr; _ } =
Loader_elf.Section.pos section
and { Loader_types.virt = size; _ } =
Loader_elf.Section.size section
in
S.Htbl.add private_symbols name
( Value,
Bitvector.of_int ~size:addr_size (base + addr) );
S.Htbl.add private_symbols name
(Size, Bitvector.of_int ~size:addr_size size);
S.Htbl.add private_symbols name
( Last,
Bitvector.of_int ~size:addr_size
(base + addr + size - 1) ))
(Loader_elf.Img.sections img);
S.Htbl.add core_symbols (Filename.basename fname)
private_symbols;
let sections = Loader_elf.Img.sections img in
let vmap, xcode, state =
Array.fold_left
(fun (vmap, xcode, state) s ->
let open Loader_elf in
let hdr = Section.header s in
let pos = hdr.Shdr.addr and size = hdr.Shdr.size in
let addr =
Bitvector.of_int ~size:addr_size (pos + base)
in
let base = Bitvector.value_of addr in
(if hdr.kind = RELA || hdr.kind = REL then
let lname =
Section.name (Array.get sections hdr.Shdr.info)
in
if
String_utils.start_with ~prefix:".got" lname
|| String_utils.start_with ~prefix:".plt" lname
then
Array.iter
(fun Rel.
{
offset;
kind = _;
symbol = { name; _ };
addend;
} ->
if name <> "" then
let addend =
Option.value ~default:0 addend
in
let reader =
Lreader.create
~endianness:env.endianness
~at:(Z.to_int base + offset - pos)
Loader_elf.read_address img'
in
let value =
Bitvector.add_int
(Lreader.Read.read reader
(addr_size lsr 3))
(-addend)
in
Queue.add
(name, value, lname, fname)
dyn_symbols)
(Rel.read img hdr));
if
(not (Section.has_flag Loader_types.Read s))
|| Imap.mem base vmap
then (vmap, xcode, state)
else
let vmap = Imap.add ~base size true vmap in
let xcode =
if Section.has_flag Loader_types.Exec s then
let p =
if Section.has_flag Loader_types.Write s
then
if transient then RWX
else (
Logger.warning
"Section %S [%a, 0x%x] has both \
Write and Execute flags.@ \
Self-modifying code is disabled and \
writes will be ignored.@ Use \
'-sse-self-written-enum N' to \
enable symbolic reasoning up to 'N \
- 1' forks."
(Section.name s) Virtual_address.pp
(Virtual_address.create pos)
size;
RX
{
base = Virtual_address.create pos;
size;
content = Img.content img s;
})
else
RX
{
base =
Virtual_address.of_bitvector addr;
size;
content = Img.content img s;
}
in
Imap.add ~base size p xcode
else xcode
in
let state =
State.memcpy ~addr size (Img.content img s)
state
in
(vmap, xcode, state))
(vmap, xcode, state) sections
in
(vmap, S.Set.add fname fmap, xcode, state))
(vmap, S.Set.empty, env.code, state)
(Loader_elf.files img')
in
Queue.iter
(fun (name, value, lname, fname) ->
try
if
Bitvector.diff value
(List.assoc Dba.Var.Tag.Value
(S.Htbl.find_all symbols name))
then (
S.Htbl.replace shadowing_symbols name (fname, Some lname);
S.Htbl.replace symbols name (Value, value))
with Not_found ->
Logger.debug ~level:4 "symbol %S resolved to %a from GOT" name
Virtual_address.pp
(Virtual_address.of_bitvector value);
S.Htbl.add symbols name (Value, value))
dyn_symbols;
let entrypoint, initializations = Isa_helper.core img' in
start :=
Dcode.script ~task:env.tasks entrypoint ~fallthrough:true prehook
parser_env;
env.code <- xcode;
let state =
List.fold_left
(fun state (var, value) -> Eval.assign var value state path)
state initializations
in
state
in
let register_hook hooks addr hook =
let others =
try Virtual_address.Map.find addr !hooks with Not_found -> []
in
hooks := Virtual_address.Map.add addr (hook :: others) !hooks
in
let path, state =
match ScriptFiles.get () with
| [] -> (Path.empty (), state)
| files ->
let initialization_callbacks = Queue.create ()
and grammar_extentions = ref []
and declaration_callbacks = ref [] in
let rec resolve_decl decl env path state = function
| [] -> Logger.fatal "Unhandled declaration %a" Script.pp decl
| app :: handlers -> (
match app decl env path state with
| None -> resolve_decl decl env path state handlers
| Some state -> state)
in
S.Htbl.iter
(fun _ plugin ->
let module P = (val plugin : PLUGIN) in
match
P.extension
(module Exploration_stats)
(module Path)
(module State)
with
| None -> ()
| Some ext ->
Option.iter Ast.Instr.register_pp P.instruction_printer;
Option.iter Script.register_pp P.declaration_printer;
grammar_extentions :=
P.grammar_extension :: !grammar_extentions;
let module E = (val ext) in
Dcode.register_callback (module E);
Option.iter
(fun init_callback ->
Queue.add init_callback initialization_callbacks)
E.initialization_callback;
Option.iter
(fun decl_callback ->
declaration_callbacks :=
decl_callback :: !declaration_callbacks)
E.declaration_callback;
Option.iter Ir.register_builtin_pp E.builtin_printer;
Option.iter
(fun at_exit_callback ->
Queue.add at_exit_callback at_exit_callbacks)
E.at_exit_callback)
plugins;
let script = Script.read_files !grammar_extentions files in
Logger.debug "@[<v>%a@]"
(Format.pp_print_list ~pp_sep:Format.pp_print_space Script.pp)
script;
let path = Path.empty () in
let state =
Queue.fold
(fun state callback -> callback path state)
state initialization_callbacks
in
( path,
List.fold_left
(fun state -> function
| Script.Starting_from (addr, prehook) -> (
try
let addr =
Script.eval_expr ~size:parser_env.wordsize addr
parser_env
in
let bv = Eval.get_value addr state path in
Logger.debug ~level:40
"the entrypoint address %a resolves to %a"
Dba_printer.Ascii.pp_bl_term addr
Bitvector.pp_hex_or_bin bv;
start :=
Dcode.script ~task:env.tasks
(Virtual_address.of_bitvector bv)
~fallthrough:true prehook parser_env;
state
with Non_unique ->
Logger.fatal
"the entrypoint address %a does not resolve to a \
unique value"
Script.Expr.pp (fst addr))
| Script.Starting_from_core prehook ->
from_core path prehook state
| Script.Load_sections names ->
List.fold_left
(fun ss name ->
try
let section =
Loader_utils.find_section_by_name name img
in
let addr =
Bitvector.of_int ~size:addr_size
(Loader.Section.pos section).virt
and size = (Loader.Section.size section).virt in
Logger.info "Load section %s (%a, %#x)" name
Bitvector.pp_hex_or_bin addr size;
State.memcpy ~addr size
(Loader.Img.content img section)
ss
with Not_found ->
(match MissingSymbol.get () with
| Error -> Logger.fatal ?e:None
| Warn -> Logger.warning ?level:None
| Quiet -> fun _ _ -> ())
"Can not load the section %S from the file." name;
ss)
state names
| Script.Load_data (load, _) -> (
match load with
| Load (len, _, addr, None) -> (
try
let addr =
Script.eval_expr ~size:parser_env.wordsize addr
parser_env
in
let bv = Eval.get_value addr state path in
Logger.debug ~level:40
"the memory initializer address %a resolves to %a"
Dba_printer.Ascii.pp_bl_term addr Bitvector.pp bv;
copy_from bv len state
with Non_unique ->
Logger.fatal
"the memory initializer address %a does not \
resolve to a unique value"
Script.Expr.pp (fst addr))
| _ -> assert false)
| Script.Concretize_stack_pointer ->
let sp, value = Isa_helper.get_stack_pointer () in
State.assign sp (State.Value.constant value) state
| Script.Import_symbols (names, file) ->
List.iter
(fun ((name, attr), _) ->
try
S.Htbl.add symbols name
(List.find
(fun (attr', _) -> attr = attr')
(S.Htbl.find_all
(S.Htbl.find core_symbols file)
name));
S.Htbl.remove shadowing_symbols name
with Not_found ->
Logger.fatal "unable to import <%s%a> from %s" name
Dba.Var.Tag.pp_attribute attr file)
names;
state
| Script.Hook (addresses, stmts, pre) ->
List.iter
(fun addr ->
let anchor =
Format.asprintf "%a" Script.Expr.pp (fst addr)
in
Logger.debug ~level:10
"@[<v 2> replace address %s by@ %a@]" anchor
Script.pp_stmts stmts;
try
let addr =
Script.eval_expr ~size:parser_env.wordsize addr
parser_env
in
let bv = Eval.get_value addr state path in
Logger.debug ~level:40
"the stub address %a resolves to %a"
Dba_printer.Ascii.pp_bl_term addr
Bitvector.pp_hex_or_bin bv;
let addr = Virtual_address.of_bitvector bv in
Virtual_address.Htbl.add hook_anchors addr anchor;
if pre then register_hook prehooks addr (anchor, stmts)
else register_hook hooks addr (anchor, stmts)
with
| Non_unique ->
Logger.fatal
"the stub address %s does not resolve to a \
unique value"
anchor
| Unresolved (name, attr) as exn
when same_symbol name attr addr -> (
match MissingSymbol.get () with
| Error -> raise exn
| Warn ->
Logger.warning
"@[<v>Can not resolve symbol <%s%a>.@ Will \
ignore the following %a@]"
name Dba.Var.Tag.pp_attribute attr
Parse_utils.pp_pos (snd addr)
| Quiet -> ()))
addresses;
state
| Script.Return_hook (((name, _), pos), stmts) ->
let addresses =
try S.Htbl.find return_instructions name
with Not_found -> (
try
let addr =
match parser_env.lookup_symbol name Value with
| Var { info = Symbol (_, (lazy value)); _ } ->
value
| _ -> raise Not_found
in
let size =
match parser_env.lookup_symbol name Size with
| Var { info = Symbol (_, (lazy value)); _ } ->
Bitvector.to_int value
| _ -> raise Not_found
in
Logger.debug ~level:5 "Return hook for <%s> [%a..%a]"
name Bitvector.pp_hex_or_bin addr
Bitvector.pp_hex_or_bin
(Bitvector.add_int addr size);
let addr = Virtual_address.of_bitvector addr in
let body =
match
Imap.find
(Virtual_address.to_bigint addr)
env.code
with
| RWX -> raise_notrace Not_found
| RX { base; content; _ } ->
Bigarray.Array1.sub content
(Virtual_address.diff addr base)
size
in
let code =
Dcode.create ~task:env.tasks addr
(Lreader.of_zero_extend_buffer
~endianness:env.endianness body)
size
in
let vertex = Dcode.disasm code addr in
let rec visit ir marked todo rets =
match todo with
| [] -> rets
| (addr, vertex) :: todo -> (
if I.Set.mem vertex marked then
visit ir marked todo rets
else
let marked = I.Set.add vertex marked in
match Dcode.G.node ir vertex with
| Terminator (Jump { tag = Return; _ }) ->
visit ir marked todo (addr :: rets)
| Fallthrough
{ kind = Instruction inst; succ } ->
visit ir marked
((Instruction.address inst, succ)
:: todo)
rets
| Fallthrough
{ kind = Hook { addr; _ }; succ } ->
visit ir marked ((addr, succ) :: todo)
rets
| Fallthrough { succ; _ }
| Goto { succ = Some succ; _ } ->
visit ir marked ((addr, succ) :: todo)
rets
| Branch { target; fallthrough; _ } ->
visit ir marked
((addr, target) :: (addr, fallthrough)
:: todo)
rets
| Goto
{ succ = None; tag = Call { base; _ }; _ }
| Terminator
(Jump { tag = Call { base; _ }; _ }) ->
let vertex = Dcode.disasm ir base in
visit ir marked ((base, vertex) :: todo)
rets
| Goto { succ = None; _ } | Terminator _ ->
raise_notrace Not_found)
in
let addresses =
visit code I.Set.empty [ (addr, vertex) ] []
in
if addresses = [] then raise_notrace Not_found;
S.Htbl.add return_instructions name addresses;
addresses
with Not_found ->
Logger.fatal
"Can not resolve symbol return instruction(s) for \
<%s> %a."
name Parse_utils.pp_pos pos)
in
let anchor = Format.sprintf "<%s> return" name in
List.iter
(fun addr ->
Virtual_address.Htbl.add hook_anchors addr anchor;
register_hook prehooks addr (anchor, stmts))
addresses;
state
| Script.Decode (opcode, stmts) ->
Dcode.register_opcode_hook (fun reader ->
if
Binstream.fold
(fun byte eq -> eq && Lreader.Read.u8 reader = byte)
opcode true
then Some (stmts, parser_env)
else None);
state
| Script.Init i -> set path state i
| Script.Explore_all ->
I.Htbl.add env.tasks (I.Htbl.length env.tasks) ();
state
| decl ->
resolve_decl decl parser_env path state
!declaration_callbacks)
state script )
in
Dcode.set_annotation_printer
(Some
(fun ppf vaddr ->
Option.iter
(fun (name, offset) ->
Format.pp_print_string ppf "\t# <";
Format.pp_print_string ppf name;
Format.pp_print_char ppf '>';
if offset > 0 then Format.fprintf ppf " + %#x" offset)
(Func.find functions vaddr)));
let in_section lo hi addr _ =
let z = Virtual_address.to_bigint addr in
Z.leq lo z && Z.leq z hi
in
let hooks =
Virtual_address.Map.merge
(fun _ prehooks hooks ->
match (prehooks, hooks) with
| None, None -> assert false
| Some prehooks, None -> Some (List.rev prehooks)
| None, Some hooks -> Some (List.rev_append hooks invalid_fallthrough)
| Some prehooks, Some hooks ->
Some
(List.rev_append prehooks
(List.rev_append hooks invalid_fallthrough)))
!prehooks !hooks
in
let dcode, whooks, hooks =
Imap.fold
(fun (lo, hi) section (dcode, whooks, others) ->
match section with
| RWX ->
let whooks', others =
Virtual_address.Map.partition (in_section lo hi) others
in
( Imap.add ~base:lo (Z.to_int (Z.sub hi lo) + 1) None dcode,
Virtual_address.Map.fold
(fun addr hooks whooks ->
Virtual_address.Map.add addr (hooks, parser_env) whooks)
whooks' whooks,
others )
| RX { base; size; content; _ } ->
let hooks, others =
Virtual_address.Map.partition (in_section lo hi) others
in
( Imap.add ~base:lo
(Z.to_int (Z.sub hi lo) + 1)
(Some
(Dcode.create ~task:env.tasks ~hooks:(hooks, parser_env)
base
(Lreader.of_zero_extend_buffer
~endianness:env.endianness content)
size))
dcode,
whooks,
others ))
env.code
(Imap.empty, Virtual_address.Map.empty, hooks)
in
Virtual_address.Map.iter
(fun addr hooks ->
let scope, _ =
Dcode.single ~task:env.tasks ~hooks:(hooks, parser_env) addr
(Lreader.of_bytes "") 0
in
Virtual_address.Htbl.add env.rocache addr scope)
hooks;
env.dcode <- dcode;
env.whooks <- whooks;
(!start, path, state)
let start () =
let filename = Kernel_options.ExecFile.get () in
Logger.debug "Running SSE on %s" filename;
let entry, path, state =
try initialize_state ()
with Halt -> Logger.fatal "Unable to resolves the initial state"
in
if I.Htbl.length env.tasks = 0 then
Logger.warning "Nothing to reach: halting..."
else
try
Sys.catch_break true;
Option.iter
(fun timeout ->
Sys.set_signal Sys.sigalrm
(Sys.Signal_handle
(fun s ->
assert (s = Sys.sigalrm);
raise_notrace Halt));
ignore (Unix.alarm timeout))
(Timeout.get_opt ());
Screen.init ();
exec Default path 0 ~max_depth:(MaxDepth.get ()) state
Virtual_address.zero entry
with
| Halt | Sys.Break -> halt ()
| err ->
Screen.release ();
raise err
let unit =
try start ()
with err -> (
match Printexc.use_printers err with
| None -> raise err
| Some msg -> Logger.fatal "%s" msg)
end