[Libguestfs] [PATCH v5 4/6] New API: internal_find_inode

[Matteo Cafasso]

The internal_find_inode command searches all entries referring to the
given inode and returns a tsk_dirent structure for each of them.

The command is able to retrieve information regarding deleted
or unaccessible files where other commands such as stat or find
would fail.

The gathered list of tsk_dirent structs is serialised into XDR format
and written to a file by the appliance.

Signed-off-by: Matteo Cafasso <noxdafox at gmail.com>
---
 daemon/tsk.c         | 52 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 generator/actions.ml |  9 +++++++++
 src/MAX_PROC_NR      |  2 +-
 3 files changed, 62 insertions(+), 1 deletion(-)

diff --git a/daemon/tsk.c b/daemon/tsk.c
index 354dfb0..00576e7 100644
--- a/daemon/tsk.c
+++ b/daemon/tsk.c
@@ -44,6 +44,7 @@ enum tsk_dirent_flags {
 
 static int open_filesystem (const char *, TSK_IMG_INFO **, TSK_FS_INFO **);
 static TSK_WALK_RET_ENUM fswalk_callback (TSK_FS_FILE *, const char *, void *);
+static TSK_WALK_RET_ENUM findino_callback (TSK_FS_FILE *, const char *, void *);
 static int send_dirent_info (TSK_FS_FILE *, const char *);
 static char file_type (TSK_FS_FILE *);
 static int file_flags (TSK_FS_FILE *fsfile);
@@ -79,6 +80,35 @@ do_internal_filesystem_walk (const mountable_t *mountable)
   return ret;
 }
 
+int
+do_internal_find_inode (const mountable_t *mountable, int64_t inode)
+{
+  int ret = -1;
+  TSK_FS_INFO *fs = NULL;
+  TSK_IMG_INFO *img = NULL;  /* Used internally by tsk_fs_dir_walk */
+  const int flags =
+    TSK_FS_DIR_WALK_FLAG_ALLOC | TSK_FS_DIR_WALK_FLAG_UNALLOC |
+    TSK_FS_DIR_WALK_FLAG_RECURSE | TSK_FS_DIR_WALK_FLAG_NOORPHAN;
+
+  ret = open_filesystem (mountable->device, &img, &fs);
+  if (ret < 0)
+    return ret;
+
+  reply (NULL, NULL);  /* Reply message. */
+
+  ret = tsk_fs_dir_walk (fs, fs->root_inum, flags,
+                         findino_callback, (void *) &inode);
+  if (ret == 0)
+    ret = send_file_end (0);  /* File transfer end. */
+  else
+    send_file_end (1);  /* Cancel file transfer. */
+
+  fs->close (fs);
+  img->close (img);
+
+  return ret;
+}
+
 /* Inspect the device and initialises the img and fs structures.
  * Return 0 on success, -1 on error.
  */
@@ -120,6 +150,28 @@ fswalk_callback (TSK_FS_FILE *fsfile, const char *path, void *data)
   return (ret == 0) ? TSK_WALK_CONT : TSK_WALK_ERROR;
 }
 
+/* Find inode, it gets called on every FS node.
+ * If the FS node address is the given one, parse it,
+ * encode it into an XDR structure and send it to the library.
+ * Return TSK_WALK_CONT on success, TSK_WALK_ERROR on error.
+ */
+static TSK_WALK_RET_ENUM
+findino_callback (TSK_FS_FILE *fsfile, const char *path, void *data)
+{
+  int ret = 0;
+  uint64_t *inode = (uint64_t *) data;
+
+  if (entry_is_dot (fsfile))
+    return TSK_WALK_CONT;
+
+  if (*inode != fsfile->name->meta_addr)
+    return TSK_WALK_CONT;
+
+  ret = send_dirent_info (fsfile, path);
+
+  return (ret == 0) ? TSK_WALK_CONT : TSK_WALK_ERROR;
+}
+
 /* Extract the information from the entry, serialize and send it out.
  * Return 0 on success, -1 on error.
  */
diff --git a/generator/actions.ml b/generator/actions.ml
index 0698b4f..55f4664 100644
--- a/generator/actions.ml
+++ b/generator/actions.ml
@@ -13204,6 +13204,15 @@ only the unallocated blocks will be extracted.
 This is useful to detect hidden data or to retrieve deleted files
 which data units have not been overwritten yet." };
 
+  { defaults with
+    name = "internal_find_inode"; added = (1, 35, 6);
+    style = RErr, [Mountable "device"; Int64 "inode"; FileOut "filename";], [];
+    proc_nr = Some 470;
+    visibility = VInternal;
+    optional = Some "libtsk";
+    shortdesc = "search the entries associated to the given inode";
+    longdesc = "Internal function for find_inode." };
+
 ]
 
 (* Non-API meta-commands available only in guestfish.
diff --git a/src/MAX_PROC_NR b/src/MAX_PROC_NR
index 1023289..5ef9d24 100644
--- a/src/MAX_PROC_NR
+++ b/src/MAX_PROC_NR
@@ -1 +1 @@
-468
+469
-- 
2.9.3