On Thu, Sep 01, 2011 at 06:17:36PM -0700, Alex Nelson wrote:
This patch adds hivex_node_struct_length and
hivex_value_struct_length
to the hivex ABI, to report the amount of hive space used for each
stored structure.
Signed-off-by: Alex Nelson <ajnelson(a)cs.ucsc.edu>
---
generator/generator.ml | 12 ++++++++++++
lib/hivex.c | 33 +++++++++++++++++++++++++++++++++
2 files changed, 45 insertions(+), 0 deletions(-)
diff --git a/generator/generator.ml b/generator/generator.ml
index 15ebc44..5a71930 100755
--- a/generator/generator.ml
+++ b/generator/generator.ml
@@ -264,6 +264,18 @@ information, and the value itself. Also, C<hivex_value_*>
functions
below which can be used to return the value in a more useful form when
you know the type in advance.";
+ "node_struct_length", (RSize, [AHive; ANode "node"]),
+ "return the length of a node",
+ "\
+Return the length of the node data structure. Returns 0
+and sets errno on error.";
+
+ "value_struct_length", (RSize, [AHive; AValue "val"]),
+ "return the length of a value data structure",
+ "\
+Return the length of the value data structure. Returns 0
+and sets errno on error.";
+
"value_value", (RLenTypeVal, [AHive; AValue "val"]),
"return data length, data type and data of a value",
"\
diff --git a/lib/hivex.c b/lib/hivex.c
index 61177d3..d8ffa63 100644
--- a/lib/hivex.c
+++ b/lib/hivex.c
@@ -585,6 +585,30 @@ hivex_root (hive_h *h)
return ret;
}
+size_t
+hivex_node_struct_length (hive_h *h, hive_node_h node)
+{
+ if (!IS_VALID_BLOCK (h, node) || !BLOCK_ID_EQ (h, node, "nk")) {
+ errno = EINVAL;
+ return 0;
+ }
+
+ struct ntreg_nk_record *nk = (struct ntreg_nk_record *) (h->addr + node);
+ size_t name_len = le16toh (nk->name_len);
+ /* -1 to avoid double-counting the first name character */
+ size_t ret = name_len + sizeof (struct ntreg_nk_record) - 1;
+ int used;
+ size_t seg_len = block_len (h, node, &used);
+ if (ret > seg_len) {
+ if (h->msglvl >= 2)
+ fprintf (stderr, "hivex_node_struct_length: returning EFAULT because"
+ " node name is too long (%zu, %zu)\n", name_len, seg_len);
+ errno = EFAULT;
+ return 0;
+ }
+ return ret;
+}
+
char *
hivex_node_name (hive_h *h, hive_node_h node)
{
@@ -1190,6 +1214,15 @@ hivex_node_get_value (hive_h *h, hive_node_h node, const char
*key)
}
size_t
+hivex_value_struct_length (hive_h *h, hive_value_h value) {
+ size_t key_len = hivex_value_key_len (h, value);
+ if (errno)
+ return 0;
+ /* -1 to avoid double-counting the first name character */
+ return key_len + sizeof (struct ntreg_vk_record) - 1;
+}
This isn't quite right. Apart from the formatting (use GNU
conventions) you can't test errno unless you set it to zero before
calling the function, since on non-error return errno is not altered.
I will fix this before I commit it, so ACK.
Rich.
--
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