From 5909fc97d0609bd77264efd7d3c2aa92f119b3eb Mon Sep 17 00:00:00 2001
From: Christophe Grenier <grenier@cgsecurity.org>
Date: Sat, 13 Mar 2021 20:15:13 +0100
Subject: [PATCH] src/file_wee.c: add Frama-C annotations

---
 src/file_wee.c | 48 ++++++++++++++++++++++++++++++++++--------------
 1 file changed, 34 insertions(+), 14 deletions(-)

diff --git a/src/file_wee.c b/src/file_wee.c
index 3bb653d4..e581bceb 100644
--- a/src/file_wee.c
+++ b/src/file_wee.c
@@ -31,39 +31,59 @@
 #include "types.h"
 #include "filegen.h"
 
+/*@ requires \valid(file_stat); */
 static void register_header_check_wee(file_stat_t *file_stat);
 
-const file_hint_t file_hint_wee= {
-  .extension="wee",
-  .description="weecast",
-  .max_filesize=PHOTOREC_MAX_FILE_SIZE,
-  .recover=1,
-  .enable_by_default=1,
-  .register_header_check=&register_header_check_wee
+const file_hint_t file_hint_wee = {
+  .extension = "wee",
+  .description = "weecast",
+  .max_filesize = PHOTOREC_MAX_FILE_SIZE,
+  .recover = 1,
+  .enable_by_default = 1,
+  .register_header_check = &register_header_check_wee
 };
 
+/*@
+  @ requires \valid(file_recovery);
+  @ requires valid_file_recovery(file_recovery);
+  @ requires \separated(file_recovery, file_recovery->handle, file_recovery->extension, &errno, &Frama_C_entropy_source);
+  @ requires file_recovery->file_check == &file_check_wee;
+  @ ensures \valid(file_recovery->handle);
+  @ assigns *file_recovery->handle, errno, file_recovery->file_size;
+  @ assigns Frama_C_entropy_source;
+  @*/
 static void file_check_wee(file_recovery_t *file_recovery)
 {
-  const unsigned char wee_footer[7]= {
-    'W' , 'E' , 'E' , 'X' , 0x21, 0x01, 0x00
+  const unsigned char wee_footer[7] = {
+    'W', 'E', 'E', 'X', 0x21, 0x01, 0x00
   };
   file_search_footer(file_recovery, wee_footer, sizeof(wee_footer), 17);
 }
 
+/*@
+  @ requires buffer_size >= 0x1b + 0xa;
+  @ requires \valid_read(buffer+(0..buffer_size-1));
+  @ requires valid_file_recovery(file_recovery);
+  @ requires \valid(file_recovery_new);
+  @ requires file_recovery_new->blocksize > 0;
+  @ requires separation: \separated(&file_hint_wee, buffer+(..), file_recovery, file_recovery_new);
+  @ ensures  \result!=0 ==> valid_file_recovery(file_recovery_new);
+  @ assigns  *file_recovery_new;
+  @*/
 static int header_check_wee(const unsigned char *buffer, const unsigned int buffer_size, const unsigned int safe_header_only, const file_recovery_t *file_recovery, file_recovery_t *file_recovery_new)
 {
-  if(buffer[0x1a]!=0xa || memcmp(&buffer[0x1b], "onMetaData", 0x0a)!=0)
+  if(buffer[0x1a] != 0xa || memcmp(&buffer[0x1b], "onMetaData", 0x0a) != 0)
     return 0;
   reset_file_recovery(file_recovery_new);
-  file_recovery_new->extension=file_hint_wee.extension;
-  file_recovery_new->file_check=&file_check_wee;
+  file_recovery_new->extension = file_hint_wee.extension;
+  file_recovery_new->file_check = &file_check_wee;
   return 1;
 }
 
 static void register_header_check_wee(file_stat_t *file_stat)
 {
-  static const unsigned char wee_header[7]=  {
-    'W' , 'E' , 'E' , 'X' , 0x21, 0x01, 0x00
+  static const unsigned char wee_header[7] = {
+    'W', 'E', 'E', 'X', 0x21, 0x01, 0x00
   };
   register_header_check(0, wee_header, sizeof(wee_header), &header_check_wee, file_stat);
 }