char name[0];
} _packed_attribute;
-/* LF (or LH) cell - contains a list of subkey references. LF and LH cells are
- * the same except they use different hashing algorithms. But this
- * implementation doesn't yet make use of the hashes anyway. */
-struct lf {
+/* Subkey list cell. There are four types. LF, LH, and LI cells reference
+ * subkey NK cells directly, while RI cells reference other subkey lists. All
+ * contain a count followed by that many 32-bit offsets. But LF and LH cells
+ * contain a 32-bit hash along with each offset, while LI and RI cells only
+ * contain offsets. */
+struct subkey_list {
#define LF_MAGIC cpu_to_le16(0x666C) /* "lf" */
#define LH_MAGIC cpu_to_le16(0x686C) /* "lh" */
+#define LI_MAGIC cpu_to_le16(0x696C) /* "li" */
+#define RI_MAGIC cpu_to_le16(0x6972) /* "ri" */
struct cell base;
- le16 num_subkeys;
- struct {
- le32 offset;
- le32 subkey_name_hash;
- } subkeys[0];
+ le16 num_offsets;
+ le32 elements[0];
} _packed_attribute;
/* Value list cell - contains a list of value references */
/* VK cell - contains a value's data, or a reference to it */
struct vk {
+#define VK_MAGIC cpu_to_le16(0x6B76)
struct cell base;
le16 name_size;
le32 data_size;
le32 data_offset;
-#define REG_NONE cpu_to_le32(0x00000000)
-#define REG_SZ cpu_to_le32(0x00000001)
-#define REG_EXPAND_SZ cpu_to_le32(0x00000002)
-#define REG_BINARY cpu_to_le32(0x00000003)
-#define REG_DWORD cpu_to_le32(0x00000004)
-#define REG_DWORD_LITTLE_ENDIAN cpu_to_le32(0x00000004)
-#define REG_DWORD_BIG_ENDIAN cpu_to_le32(0x00000005)
-#define REG_LINK cpu_to_le32(0x00000006)
-#define REG_MULTI_SZ cpu_to_le32(0x00000007)
-#define REG_RESOURCE_LIST cpu_to_le32(0x00000008)
-#define REG_FULL_RESOURCE_DESCRIPTOR cpu_to_le32(0x00000009)
-#define REG_RESOURCE_REQUIREMENTS_LIST cpu_to_le32(0x0000000A)
-#define REG_QWORD cpu_to_le32(0x0000000B)
-#define REG_QWORD_LITTLE_ENDIAN cpu_to_le32(0x0000000B)
+#define REG_NONE cpu_to_le32(0)
+#define REG_SZ cpu_to_le32(1)
+#define REG_EXPAND_SZ cpu_to_le32(2)
+#define REG_BINARY cpu_to_le32(3)
+#define REG_DWORD cpu_to_le32(4)
+#define REG_DWORD_LITTLE_ENDIAN cpu_to_le32(4)
+#define REG_DWORD_BIG_ENDIAN cpu_to_le32(5)
+#define REG_LINK cpu_to_le32(6)
+#define REG_MULTI_SZ cpu_to_le32(7)
+#define REG_RESOURCE_LIST cpu_to_le32(8)
+#define REG_FULL_RESOURCE_DESCRIPTOR cpu_to_le32(9)
+#define REG_RESOURCE_REQUIREMENTS_LIST cpu_to_le32(10)
+#define REG_QWORD cpu_to_le32(11)
+#define REG_QWORD_LITTLE_ENDIAN cpu_to_le32(11)
le32 data_type;
#define VK_COMPRESSED_NAME cpu_to_le16(0x0001)
le16 flags;
u8 data[0];
};
+/* Arbitrary limits for safety */
+#define MAX_VALUES 65536
+#define MAX_SUBKEYS 65536
+#define MAX_SUBKEY_LIST_LEVELS 5
+#define MAX_SUBKEY_LISTS 4096
+
static enum hive_status
translate_wimlib_error(int ret)
{
return get_cell_pointer(regf, offset, wanted_size) != NULL;
}
-/*
- * Given a registry key cell @nk, look up the next component of the key
- * *key_namep. If found, return HIVE_OK, advance *key_namep past the key name
- * component, and return the subkey cell in @sub_nk_ret. Otherwise, return
- * another HIVE_* error code.
- */
-static enum hive_status
-lookup_subkey(const struct regf *regf, const utf16lechar **key_namep,
- const struct nk *nk, const struct nk **sub_nk_ret)
-{
- const utf16lechar *key_name = *key_namep;
- size_t key_name_nchars = 0;
- size_t num_subkeys;
- const struct cell *subkey_list;
+struct subkey_iteration_stats {
- for (const utf16lechar *p = key_name;
- *p && *p != cpu_to_le16('\\'); p++)
- key_name_nchars++;
+ /* The number of additional levels of descendent subkey lists that may
+ * be visited (currently, i.e. at this point in the iteration) before
+ * our safety limit of MAX_SUBKEY_LIST_LEVELS is reached */
+ u32 levels_remaining;
- num_subkeys = le32_to_cpu(nk->num_subkeys);
+ /* The number of additional subkey lists that may be visited until our
+ * safety limit of MAX_SUBKEY_LISTS is reached */
+ u32 subkey_lists_remaining;
- if (num_subkeys == 0) /* No subkeys? */
- return HIVE_KEY_NOT_FOUND;
+ /* The number of subkeys remaining to be found. Since the number of
+ * subkeys is known from the parent nk cell, this should be 0 at the end
+ * of the iteration. */
+ u32 subkeys_remaining;
+};
+
+typedef enum hive_status (*subkey_cb_t)(const struct nk *, void *);
- if (num_subkeys > 65536) /* Arbitrary limit */
+static enum hive_status
+iterate_subkeys_recursive(const struct regf *regf, le32 subkey_list_offset,
+ subkey_cb_t cb, void *cb_ctx,
+ struct subkey_iteration_stats *stats)
+{
+ const struct subkey_list *list;
+ unsigned num_offsets;
+ size_t extra_size;
+ unsigned increment;
+ const le32 *p;
+ enum hive_status status;
+
+ if (stats->levels_remaining == 0 || stats->subkey_lists_remaining == 0)
return HIVE_CORRUPT;
- /* Find the subkey list cell. */
- subkey_list = get_cell_pointer(regf, nk->subkey_list_offset,
- sizeof(struct cell));
- if (!subkey_list)
+ stats->subkey_lists_remaining--;
+
+ list = get_cell_pointer(regf, subkey_list_offset,
+ sizeof(struct subkey_list));
+ if (!list)
return HIVE_CORRUPT;
- if (subkey_list->magic == LF_MAGIC || subkey_list->magic == LH_MAGIC) {
- const struct lf *lf;
+ num_offsets = le16_to_cpu(list->num_offsets);
+ extra_size = num_offsets * sizeof(list->elements[0]);
+ increment = 1;
- /* Handle LF and LH subkey lists. */
+ if (list->base.magic == LF_MAGIC || list->base.magic == LH_MAGIC) {
+ /* Hashes are included */
+ extra_size *= 2;
+ increment = 2;
+ }
- lf = get_cell_pointer(regf, nk->subkey_list_offset,
- sizeof(struct lf) +
- (num_subkeys * sizeof(lf->subkeys[0])));
- if (!lf)
- return HIVE_CORRUPT;
+ if (!revalidate_cell(regf, subkey_list_offset,
+ sizeof(struct subkey_list) + extra_size))
+ return HIVE_CORRUPT;
- /* Look for the subkey in the subkey list. */
- for (size_t i = 0; i < num_subkeys; i++) {
+ p = list->elements;
+
+ switch (list->base.magic) {
+ case LF_MAGIC:
+ case LH_MAGIC:
+ case LI_MAGIC:
+ /* Children are subkeys */
+ if (stats->subkeys_remaining < num_offsets)
+ return HIVE_CORRUPT;
+ stats->subkeys_remaining -= num_offsets;
+ while (num_offsets--) {
const struct nk *sub_nk;
- size_t name_size;
- sub_nk = get_cell_pointer(regf, lf->subkeys[i].offset,
- sizeof(struct nk));
- if (!sub_nk)
+ sub_nk = get_cell_pointer(regf, *p, sizeof(struct nk));
+ if (!sub_nk || sub_nk->base.magic != NK_MAGIC)
return HIVE_CORRUPT;
- name_size = le16_to_cpu(sub_nk->name_size);
-
- if (!revalidate_cell(regf, lf->subkeys[i].offset,
- sizeof(struct nk) + name_size))
+ if (!revalidate_cell(regf, *p, sizeof(struct nk) +
+ le16_to_cpu(sub_nk->name_size)))
return HIVE_CORRUPT;
- if (names_equal(key_name, key_name_nchars,
- sub_nk->name, name_size,
- (sub_nk->flags & NK_COMPRESSED_NAME)))
- {
- key_name += key_name_nchars;
- while (*key_name == cpu_to_le16('\\'))
- key_name++;
- *key_namep = key_name;
- *sub_nk_ret = sub_nk;
- return HIVE_OK;
- }
+ status = (*cb)(sub_nk, cb_ctx);
+ if (status != HIVE_OK)
+ return status;
+ p += increment;
}
- return HIVE_KEY_NOT_FOUND;
+ return HIVE_OK;
+ case RI_MAGIC:
+ /* Children are subkey lists */
+ status = HIVE_OK;
+ stats->levels_remaining--;
+ while (num_offsets--) {
+ status = iterate_subkeys_recursive(regf, *p++,
+ cb, cb_ctx, stats);
+ if (status != HIVE_OK)
+ break;
+ }
+ stats->levels_remaining++;
+ return status;
+ default:
+ return HIVE_UNSUPPORTED;
}
+}
- return HIVE_UNSUPPORTED;
+/* Call @cb on each subkey cell of the key @nk. */
+static enum hive_status
+iterate_subkeys(const struct regf *regf, const struct nk *nk,
+ subkey_cb_t cb, void *cb_ctx)
+{
+ u32 num_subkeys = le32_to_cpu(nk->num_subkeys);
+ struct subkey_iteration_stats stats;
+ enum hive_status status;
+
+ if (num_subkeys == 0)
+ return HIVE_OK;
+
+ if (num_subkeys > MAX_SUBKEYS)
+ return HIVE_CORRUPT;
+
+ stats.levels_remaining = MAX_SUBKEY_LIST_LEVELS;
+ stats.subkey_lists_remaining = MAX_SUBKEY_LISTS;
+ stats.subkeys_remaining = num_subkeys;
+
+ status = iterate_subkeys_recursive(regf, nk->subkey_list_offset,
+ cb, cb_ctx, &stats);
+ if (stats.subkeys_remaining != 0 && status == HIVE_OK)
+ status = HIVE_CORRUPT;
+ return status;
+}
+
+struct lookup_subkey_ctx {
+ const utf16lechar *key_name;
+ size_t key_name_nchars;
+ const struct nk *result;
+};
+
+static enum hive_status
+lookup_subkey_cb(const struct nk *sub_nk, void *_ctx)
+{
+ struct lookup_subkey_ctx *ctx = _ctx;
+
+ if (names_equal(ctx->key_name, ctx->key_name_nchars,
+ sub_nk->name, le16_to_cpu(sub_nk->name_size),
+ (sub_nk->flags & NK_COMPRESSED_NAME)))
+ {
+ ctx->result = sub_nk;
+ return HIVE_ITERATION_STOPPED;
+ }
+
+ return HIVE_OK;
+}
+
+/*
+ * Given a registry key cell @nk, look up the next component of the key
+ * *key_namep. If found, return HIVE_OK, advance *key_namep past the key name
+ * component, and return the subkey cell in @sub_nk_ret. Otherwise, return
+ * another HIVE_* error code.
+ */
+static enum hive_status
+lookup_subkey(const struct regf *regf, const utf16lechar **key_namep,
+ const struct nk *nk, const struct nk **sub_nk_ret)
+{
+ const utf16lechar *key_name = *key_namep;
+ size_t key_name_nchars = 0;
+ struct lookup_subkey_ctx ctx;
+ enum hive_status status;
+
+ while (key_name[key_name_nchars] != cpu_to_le16('\0') &&
+ key_name[key_name_nchars] != cpu_to_le16('\\'))
+ key_name_nchars++;
+
+ ctx.key_name = key_name;
+ ctx.key_name_nchars = key_name_nchars;
+ ctx.result = NULL;
+
+ status = iterate_subkeys(regf, nk, lookup_subkey_cb, &ctx);
+ if (!ctx.result) {
+ if (status == HIVE_OK)
+ status = HIVE_KEY_NOT_FOUND;
+ return status;
+ }
+
+ key_name += key_name_nchars;
+ while (*key_name == cpu_to_le16('\\'))
+ key_name++;
+ *key_namep = key_name;
+ *sub_nk_ret = ctx.result;
+ return HIVE_OK;
}
/* Find the nk cell for the key named @key_name in the registry hive @regf. */
const utf16lechar *key_uname, *key_unamep;
nk = get_cell_pointer(regf, regf->root_key_offset, sizeof(struct nk));
- if (!nk)
+ if (!nk || nk->base.magic != NK_MAGIC)
return HIVE_CORRUPT;
status = translate_wimlib_error(tstr_get_utf16le(key_name, &key_uname));
if (num_values == 0) /* No values? */
return HIVE_VALUE_NOT_FOUND;
- if (num_values > 65536) /* Arbitrary limit */
+ if (num_values > MAX_VALUES)
return HIVE_CORRUPT;
value_list = get_cell_pointer(regf, nk->value_list_offset,
status = HIVE_CORRUPT;
vk = get_cell_pointer(regf, value_list->vk_offsets[i],
sizeof(struct vk));
- if (!vk)
+ if (!vk || vk->base.magic != VK_MAGIC)
goto out;
name_size = le16_to_cpu(vk->name_size);
return status;
}
+static enum hive_status
+append_subkey_name(const struct nk *sub_nk, void *_next_subkey_p)
+{
+ size_t name_size = le16_to_cpu(sub_nk->name_size);
+ tchar *subkey;
+ tchar ***next_subkeyp = _next_subkey_p;
+
+ if (sub_nk->flags & NK_COMPRESSED_NAME) {
+ subkey = MALLOC((name_size + 1) * sizeof(tchar));
+ if (!subkey)
+ return HIVE_OUT_OF_MEMORY;
+ for (size_t i = 0; i < name_size; i++)
+ subkey[i] = sub_nk->name[i];
+ subkey[name_size] = '\0';
+ } else {
+ size_t dummy;
+ enum hive_status status;
+
+ status = translate_wimlib_error(
+ utf16le_to_tstr((utf16lechar *)sub_nk->name,
+ name_size, &subkey, &dummy));
+ if (status != HIVE_OK)
+ return status;
+ }
+
+ **next_subkeyp = subkey;
+ ++*next_subkeyp;
+ return HIVE_OK;
+}
+
/* List the subkeys of the specified registry key. */
enum hive_status
hive_list_subkeys(const struct regf *regf, const tchar *key_name,
{
enum hive_status status;
const struct nk *nk;
- size_t num_subkeys;
- const struct cell *subkey_list;
tchar **subkeys;
+ tchar **next_subkey;
- /* Look up the nk cell for the key. */
status = lookup_key(regf, key_name, &nk);
if (status != HIVE_OK)
return status;
- num_subkeys = le32_to_cpu(nk->num_subkeys);
-
- if (num_subkeys > 65536) /* Arbitrary limit */
+ if (le32_to_cpu(nk->num_subkeys) > MAX_SUBKEYS)
return HIVE_CORRUPT;
- /* Prepare the array of subkey names to return. */
- subkeys = CALLOC(num_subkeys + 1, sizeof(subkeys[0]));
+ subkeys = CALLOC(le32_to_cpu(nk->num_subkeys) + 1, sizeof(subkeys[0]));
if (!subkeys)
return HIVE_OUT_OF_MEMORY;
- *subkeys_ret = subkeys;
-
- /* No subkeys? */
- if (num_subkeys == 0)
- return HIVE_OK;
-
- /* Find the subkey list cell. */
- status = HIVE_CORRUPT;
- subkey_list = get_cell_pointer(regf, nk->subkey_list_offset,
- sizeof(struct cell));
- if (!subkey_list)
- goto err;
-
- if (subkey_list->magic == LF_MAGIC || subkey_list->magic == LH_MAGIC) {
- const struct lf *lf;
-
- /* Handle LF and LH subkey lists. */
-
- status = HIVE_CORRUPT;
- lf = get_cell_pointer(regf, nk->subkey_list_offset,
- sizeof(struct lf) +
- (num_subkeys * sizeof(lf->subkeys[0])));
- if (!lf)
- goto err;
-
- /* Iterate through the subkey list and gather the subkey names.
- */
- for (size_t i = 0; i < num_subkeys; i++) {
- const struct nk *sub_nk;
- size_t name_size;
- tchar *subkey;
- size_t dummy;
-
- status = HIVE_CORRUPT;
- sub_nk = get_cell_pointer(regf, lf->subkeys[i].offset,
- sizeof(struct nk));
- if (!sub_nk)
- goto err;
-
- name_size = le16_to_cpu(sub_nk->name_size);
-
- if (!revalidate_cell(regf, lf->subkeys[i].offset,
- sizeof(struct nk) + name_size))
- goto err;
-
- if (sub_nk->flags & NK_COMPRESSED_NAME) {
- status = HIVE_OUT_OF_MEMORY;
- subkey = MALLOC((name_size + 1) * sizeof(tchar));
- if (!subkey)
- goto err;
- for (size_t j = 0; j < name_size; j++)
- subkey[j] = sub_nk->name[j];
- subkey[name_size] = '\0';
- } else {
- status = translate_wimlib_error(
- utf16le_to_tstr((utf16lechar *)sub_nk->name,
- name_size, &subkey, &dummy));
- if (status != HIVE_OK)
- goto err;
- }
- subkeys[i] = subkey;
- }
- return HIVE_OK;
- }
- status = HIVE_UNSUPPORTED;
-err:
- hive_free_subkeys_list(subkeys);
+ next_subkey = subkeys;
+ status = iterate_subkeys(regf, nk, append_subkey_name, &next_subkey);
+ if (status == HIVE_OK)
+ *subkeys_ret = subkeys;
+ else
+ hive_free_subkeys_list(subkeys);
return status;
}
return "HIVE_VALUE_IS_WRONG_TYPE";
case HIVE_OUT_OF_MEMORY:
return "HIVE_OUT_OF_MEMORY";
+ case HIVE_ITERATION_STOPPED:
+ return "HIVE_ITERATION_STOPPED";
}
return NULL;
}
git://wimlib.net / wimlib / commitdiff