hivex: Split value_key function into value_key and value_key_len

[hivex.git] / lib / hivex.c

diff --git a/lib/hivex.c b/lib/hivex.c
index a3f5171..a183527 100644 (file)
--- a/lib/hivex.c
+++ b/lib/hivex.c
@@ -294,9 +294,16 @@ hivex_open (const char *filename, int flags)
   if (h->filename == NULL)
     goto error;
 
+#ifdef O_CLOEXEC
   h->fd = open (filename, O_RDONLY | O_CLOEXEC);
+#else
+  h->fd = open (filename, O_RDONLY);
+#endif
   if (h->fd == -1)
     goto error;
+#ifndef O_CLOEXEC
+  fcntl (h->fd, F_SETFD, FD_CLOEXEC);
+#endif
 
   struct stat statbuf;
   if (fstat (h->fd, &statbuf) == -1)
@@ -1182,8 +1189,8 @@ hivex_node_get_value (hive_h *h, hive_node_h node, const char *key)
   return ret;
 }
 
-char *
-hivex_value_key (hive_h *h, hive_value_h value)
+size_t
+hivex_value_key_len (hive_h *h, hive_value_h value)
 {
   if (!IS_VALID_BLOCK (h, value) || !BLOCK_ID_EQ (h, value, "vk")) {
     errno = EINVAL;
@@ -1192,23 +1199,39 @@ hivex_value_key (hive_h *h, hive_value_h value)
 
   struct ntreg_vk_record *vk = (struct ntreg_vk_record *) (h->addr + value);
 
-  /* AFAIK the key is always plain ASCII, so no conversion to UTF-8 is
-   * necessary.  However we do need to nul-terminate the string.
-   */
-
   /* vk->name_len is unsigned, 16 bit, so this is safe ...  However
    * we have to make sure the length doesn't exceed the block length.
    */
-  size_t len = le16toh (vk->name_len);
+  size_t ret = le16toh (vk->name_len);
   size_t seg_len = block_len (h, value, NULL);
-  if (sizeof (struct ntreg_vk_record) + len - 1 > seg_len) {
+  if (sizeof (struct ntreg_vk_record) + ret - 1 > seg_len) {
     if (h->msglvl >= 2)
-      fprintf (stderr, "hivex_value_key: returning EFAULT"
+      fprintf (stderr, "hivex_value_key_len: returning EFAULT"
                " because key length is too long (%zu, %zu)\n",
-               len, seg_len);
+               ret, seg_len);
     errno = EFAULT;
-    return NULL;
+    return 0;
   }
+  return ret;
+}
+
+char *
+hivex_value_key (hive_h *h, hive_value_h value)
+{
+  if (!IS_VALID_BLOCK (h, value) || !BLOCK_ID_EQ (h, value, "vk")) {
+    errno = EINVAL;
+    return 0;
+  }
+
+  struct ntreg_vk_record *vk = (struct ntreg_vk_record *) (h->addr + value);
+
+  /* AFAIK the key is always plain ASCII, so no conversion to UTF-8 is
+   * necessary.  However we do need to nul-terminate the string.
+   */
+  errno = 0;
+  size_t len = hivex_value_key_len (h, value);
+  if (len == 0 && errno != 0)
+    return NULL;
 
   char *ret = malloc (len + 1);
   if (ret == NULL)