/* hivex - Windows Registry "hive" extraction library.
- * Copyright (C) 2009 Red Hat Inc.
+ * Copyright (C) 2009-2010 Red Hat Inc.
* Derived from code by Petter Nordahl-Hagen under a compatible license:
* Copyright (c) 1997-2007 Petter Nordahl-Hagen.
* Derived from code by Markus Stephany under a compatible license:
#include <sys/mman.h>
#include <sys/stat.h>
#include <assert.h>
-#ifdef HAVE_ENDIAN_H
-#include <endian.h>
-#endif
-#ifdef HAVE_BYTESWAP_H
-#include <byteswap.h>
+
+#include "full-read.h"
+#include "full-write.h"
+
+#ifndef O_CLOEXEC
+#define O_CLOEXEC 0
#endif
#define STREQ(a,b) (strcmp((a),(b)) == 0)
//#define STRCASENEQLEN(a,b,n) (strncasecmp((a),(b),(n)) != 0)
//#define STRPREFIX(a,b) (strncmp((a),(b),strlen((b))) == 0)
-#if __BYTE_ORDER == __LITTLE_ENDIAN
-#ifndef be32toh
-#define be32toh(x) __bswap_32 (x)
-#endif
-#ifndef be64toh
-#define be64toh(x) __bswap_64 (x)
-#endif
-#ifndef le16toh
-#define le16toh(x) (x)
-#endif
-#ifndef le32toh
-#define le32toh(x) (x)
-#endif
-#ifndef le64toh
-#define le64toh(x) (x)
-#endif
-#else
-#ifndef be32toh
-#define be32toh(x) (x)
-#endif
-#ifndef be64toh
-#define be64toh(x) (x)
-#endif
-#ifndef le16toh
-#define le16toh(x) __bswap_16 (x)
-#endif
-#ifndef le32toh
-#define le32toh(x) __bswap_32 (x)
-#endif
-#ifndef le64toh
-#define le64toh(x) __bswap_64 (x)
-#endif
-#endif
-
#include "hivex.h"
+#include "byte_conversions.h"
static char *windows_utf16_to_utf8 (/* const */ char *input, size_t len);
int fd;
size_t size;
int msglvl;
+ int writable;
- /* Memory-mapped (readonly) registry file. */
+ /* Registry file, memory mapped if read-only, or malloc'd if writing. */
union {
char *addr;
struct ntreg_header *hdr;
/* Fields from the header, extracted from little-endianness hell. */
size_t rootoffs; /* Root key offset (always an nk-block). */
size_t endpages; /* Offset of end of pages. */
+
+ /* For writing. */
+ size_t endblocks; /* Offset to next block allocation (0
+ if not allocated anything yet). */
};
/* NB. All fields are little endian. */
int32_t seg_len; /* length (always -ve because used) */
char id[2]; /* "nk" */
uint16_t flags;
- char timestamp[12];
+ char timestamp[8];
+ uint32_t unknown1;
uint32_t parent; /* offset of owner/parent */
uint32_t nr_subkeys; /* number of subkeys */
- uint32_t unknown1;
+ uint32_t nr_subkeys_volatile;
uint32_t subkey_lf; /* lf record containing list of subkeys */
- uint32_t unknown2;
+ uint32_t subkey_lf_volatile;
uint32_t nr_values; /* number of values */
uint32_t vallist; /* value-list record */
uint32_t sk; /* offset of sk-record */
uint32_t classname; /* offset of classname record */
- char unknown3[16];
- uint32_t unknown4;
+ uint16_t max_subkey_name_len; /* maximum length of a subkey name in bytes
+ if the subkey was reencoded as UTF-16LE */
+ uint16_t unknown2;
+ uint32_t unknown3;
+ uint32_t max_vk_name_len; /* maximum length of any vk name in bytes
+ if the name was reencoded as UTF-16LE */
+ uint32_t max_vk_data_len; /* maximum length of any vk data in bytes */
+ uint32_t unknown6;
uint16_t name_len; /* length of name */
uint16_t classname_len; /* length of classname */
char name[1]; /* name follows here */
uint16_t nr_keys; /* number of keys in this record */
struct {
uint32_t offset; /* offset of nk-record for this subkey */
- char name[4]; /* first 4 characters of subkey name */
+ char hash[4]; /* hash of subkey name */
} keys[1];
} __attribute__((__packed__));
*/
uint32_t data_len;
uint32_t data_offset; /* pointer to the data (or data if inline) */
- hive_type data_type; /* type of the data */
+ uint32_t data_type; /* type of the data */
uint16_t flags; /* bit 0 set => key name ASCII,
bit 0 clr => key name UTF-16.
- Only seen ASCII here in the wild. */
+ Only seen ASCII here in the wild.
+ NB: this is CLEAR for default key. */
uint16_t unknown2;
char name[1]; /* key name follows here */
} __attribute__((__packed__));
static uint32_t
-header_checksum (hive_h *h)
+header_checksum (const hive_h *h)
{
uint32_t *daddr = (uint32_t *) h->addr;
size_t i;
if (h->msglvl >= 2)
fprintf (stderr, "hivex_open: created handle %p\n", h);
+ h->writable = !!(flags & HIVEX_OPEN_WRITE);
h->filename = strdup (filename);
if (h->filename == NULL)
goto error;
- h->fd = open (filename, O_RDONLY);
+ h->fd = open (filename, O_RDONLY | O_CLOEXEC);
if (h->fd == -1)
goto error;
h->size = statbuf.st_size;
- h->addr = mmap (NULL, h->size, PROT_READ, MAP_SHARED, h->fd, 0);
- if (h->addr == MAP_FAILED)
- goto error;
+ if (!h->writable) {
+ h->addr = mmap (NULL, h->size, PROT_READ, MAP_SHARED, h->fd, 0);
+ if (h->addr == MAP_FAILED)
+ goto error;
- if (h->msglvl >= 2)
- fprintf (stderr, "hivex_open: mapped file at %p\n", h->addr);
+ if (h->msglvl >= 2)
+ fprintf (stderr, "hivex_open: mapped file at %p\n", h->addr);
+ } else {
+ h->addr = malloc (h->size);
+ if (h->addr == NULL)
+ goto error;
+
+ if (full_read (h->fd, h->addr, h->size) < h->size)
+ goto error;
+ }
/* Check header. */
if (h->hdr->magic[0] != 'r' ||
int used;
seg_len = block_len (h, blkoff, &used);
if (seg_len <= 4 || (seg_len & 3) != 0) {
- fprintf (stderr, "hivex: %s: block size %d at %zu, bad registry\n",
+ fprintf (stderr, "hivex: %s: block size %" PRIu32 " at 0x%zx, bad registry\n",
filename, le32toh (block->seg_len), blkoff);
errno = ENOTSUP;
goto error;
int err = errno;
if (h) {
free (h->bitmap);
- if (h->addr && h->size && h->addr != MAP_FAILED)
- munmap (h->addr, h->size);
+ if (h->addr && h->size && h->addr != MAP_FAILED) {
+ if (!h->writable)
+ munmap (h->addr, h->size);
+ else
+ free (h->addr);
+ }
if (h->fd >= 0)
close (h->fd);
free (h->filename);
int r;
free (h->bitmap);
- munmap (h->addr, h->size);
+ if (!h->writable)
+ munmap (h->addr, h->size);
+ else
+ free (h->addr);
r = close (h->fd);
free (h->filename);
free (h);
return r;
}
+/*----------------------------------------------------------------------
+ * Reading.
+ */
+
hive_node_h
hivex_root (hive_h *h)
{
}
#endif
-hive_node_h *
-hivex_node_children (hive_h *h, hive_node_h node)
+/* Structure for returning 0-terminated lists of offsets (nodes,
+ * values, etc).
+ */
+struct offset_list {
+ size_t *offsets;
+ size_t len;
+ size_t alloc;
+};
+
+static void
+init_offset_list (struct offset_list *list)
+{
+ list->len = 0;
+ list->alloc = 0;
+ list->offsets = NULL;
+}
+
+#define INIT_OFFSET_LIST(name) \
+ struct offset_list name; \
+ init_offset_list (&name)
+
+/* Preallocates the offset_list, but doesn't make the contents longer. */
+static int
+grow_offset_list (struct offset_list *list, size_t alloc)
+{
+ assert (alloc >= list->len);
+ size_t *p = realloc (list->offsets, alloc * sizeof (size_t));
+ if (p == NULL)
+ return -1;
+ list->offsets = p;
+ list->alloc = alloc;
+ return 0;
+}
+
+static int
+add_to_offset_list (struct offset_list *list, size_t offset)
+{
+ if (list->len >= list->alloc) {
+ if (grow_offset_list (list, list->alloc ? list->alloc * 2 : 4) == -1)
+ return -1;
+ }
+ list->offsets[list->len] = offset;
+ list->len++;
+ return 0;
+}
+
+static void
+free_offset_list (struct offset_list *list)
+{
+ free (list->offsets);
+}
+
+static size_t *
+return_offset_list (struct offset_list *list)
+{
+ if (add_to_offset_list (list, 0) == -1)
+ return NULL;
+ return list->offsets; /* caller frees */
+}
+
+/* Iterate over children, returning child nodes and intermediate blocks. */
+static int
+get_children (hive_h *h, hive_node_h node,
+ hive_node_h **children_ret, size_t **blocks_ret)
{
if (!IS_VALID_BLOCK (h, node) || !BLOCK_ID_EQ (h, node, "nk")) {
errno = EINVAL;
- return NULL;
+ return -1;
}
struct ntreg_nk_record *nk = (struct ntreg_nk_record *) (h->addr + node);
size_t nr_subkeys_in_nk = le32toh (nk->nr_subkeys);
+ INIT_OFFSET_LIST (children);
+ INIT_OFFSET_LIST (blocks);
+
/* Deal with the common "no subkeys" case quickly. */
- hive_node_h *ret;
- if (nr_subkeys_in_nk == 0) {
- ret = malloc (sizeof (hive_node_h));
- if (ret == NULL)
- return NULL;
- ret[0] = 0;
- return ret;
- }
+ if (nr_subkeys_in_nk == 0)
+ goto ok;
/* Arbitrarily limit the number of subkeys we will ever deal with. */
if (nr_subkeys_in_nk > 1000000) {
errno = ERANGE;
- return NULL;
+ goto error;
}
+ /* Preallocate space for the children. */
+ if (grow_offset_list (&children, nr_subkeys_in_nk) == -1)
+ goto error;
+
/* The subkey_lf field can point either to an lf-record, which is
* the common case, or if there are lots of subkeys, to an
* ri-record.
fprintf (stderr, "hivex_node_children: returning EFAULT because subkey_lf is not a valid block (%zu)\n",
subkey_lf);
errno = EFAULT;
- return NULL;
+ goto error;
}
+ if (add_to_offset_list (&blocks, subkey_lf) == -1)
+ goto error;
+
struct ntreg_hbin_block *block =
(struct ntreg_hbin_block *) (h->addr + subkey_lf);
if (nr_subkeys_in_nk != nr_subkeys_in_lf) {
errno = ENOTSUP;
- return NULL;
+ goto error;
}
size_t len = block_len (h, subkey_lf, NULL);
fprintf (stderr, "hivex_node_children: returning EFAULT because too many subkeys (%zu, %zu)\n",
nr_subkeys_in_lf, len);
errno = EFAULT;
- return NULL;
+ goto error;
}
- /* Allocate space for the returned values. Note that
- * nr_subkeys_in_lf is limited to a 16 bit value.
- */
- ret = malloc ((1 + nr_subkeys_in_lf) * sizeof (hive_node_h));
- if (ret == NULL)
- return NULL;
-
size_t i;
for (i = 0; i < nr_subkeys_in_lf; ++i) {
- hive_node_h subkey = lf->keys[i].offset;
+ hive_node_h subkey = le32toh (lf->keys[i].offset);
subkey += 0x1000;
if (!IS_VALID_BLOCK (h, subkey)) {
if (h->msglvl >= 2)
fprintf (stderr, "hivex_node_children: returning EFAULT because subkey is not a valid block (0x%zx)\n",
subkey);
errno = EFAULT;
- free (ret);
- return NULL;
+ goto error;
}
- ret[i] = subkey;
+ if (add_to_offset_list (&children, subkey) == -1)
+ goto error;
}
- ret[i] = 0;
- return ret;
+ goto ok;
}
/* Points to ri-record? */
else if (block->id[0] == 'r' && block->id[1] == 'i') {
fprintf (stderr, "hivex_node_children: returning EFAULT because ri-offset is not a valid block (0x%zx)\n",
offset);
errno = EFAULT;
- return NULL;
+ goto error;
}
if (!BLOCK_ID_EQ (h, offset, "lf") && !BLOCK_ID_EQ (h, offset, "lh")) {
errno = ENOTSUP;
- return NULL;
+ goto error;
}
+ if (add_to_offset_list (&blocks, offset) == -1)
+ goto error;
+
struct ntreg_lf_record *lf =
(struct ntreg_lf_record *) (h->addr + offset);
if (nr_subkeys_in_nk != count) {
errno = ENOTSUP;
- return NULL;
+ goto error;
}
/* Copy list of children. Note nr_subkeys_in_nk is limited to
* something reasonable above.
*/
- ret = malloc ((1 + nr_subkeys_in_nk) * sizeof (hive_node_h));
- if (ret == NULL)
- return NULL;
-
- count = 0;
for (i = 0; i < nr_offsets; ++i) {
hive_node_h offset = ri->offset[i];
offset += 0x1000;
fprintf (stderr, "hivex_node_children: returning EFAULT because ri-offset is not a valid block (0x%zx)\n",
offset);
errno = EFAULT;
- return NULL;
+ goto error;
}
if (!BLOCK_ID_EQ (h, offset, "lf") && !BLOCK_ID_EQ (h, offset, "lh")) {
errno = ENOTSUP;
- return NULL;
+ goto error;
}
struct ntreg_lf_record *lf =
size_t j;
for (j = 0; j < le16toh (lf->nr_keys); ++j) {
- hive_node_h subkey = lf->keys[j].offset;
+ hive_node_h subkey = le32toh (lf->keys[j].offset);
subkey += 0x1000;
if (!IS_VALID_BLOCK (h, subkey)) {
if (h->msglvl >= 2)
fprintf (stderr, "hivex_node_children: returning EFAULT because indirect subkey is not a valid block (0x%zx)\n",
subkey);
errno = EFAULT;
- free (ret);
- return NULL;
+ goto error;
}
- ret[count++] = subkey;
+ if (add_to_offset_list (&children, subkey) == -1)
+ goto error;
}
}
- ret[count] = 0;
-
- return ret;
+ goto ok;
}
- else {
- errno = ENOTSUP;
+ /* else not supported, set errno and fall through */
+ errno = ENOTSUP;
+ error:
+ free_offset_list (&children);
+ free_offset_list (&blocks);
+ return -1;
+
+ ok:
+ *children_ret = return_offset_list (&children);
+ *blocks_ret = return_offset_list (&blocks);
+ if (!*children_ret || !*blocks_ret)
+ goto error;
+ return 0;
+}
+
+hive_node_h *
+hivex_node_children (hive_h *h, hive_node_h node)
+{
+ hive_node_h *children;
+ size_t *blocks;
+
+ if (get_children (h, node, &children, &blocks) == -1)
return NULL;
- }
+
+ free (blocks);
+ return children;
}
/* Very inefficient, but at least having a separate API call
return ret;
}
-hive_value_h *
-hivex_node_values (hive_h *h, hive_node_h node)
+static int
+get_values (hive_h *h, hive_node_h node,
+ hive_value_h **values_ret, size_t **blocks_ret)
{
if (!IS_VALID_BLOCK (h, node) || !BLOCK_ID_EQ (h, node, "nk")) {
errno = EINVAL;
- return 0;
+ return -1;
}
struct ntreg_nk_record *nk = (struct ntreg_nk_record *) (h->addr + node);
if (h->msglvl >= 2)
fprintf (stderr, "hivex_node_values: nr_values = %zu\n", nr_values);
+ INIT_OFFSET_LIST (values);
+ INIT_OFFSET_LIST (blocks);
+
/* Deal with the common "no values" case quickly. */
- hive_node_h *ret;
- if (nr_values == 0) {
- ret = malloc (sizeof (hive_node_h));
- if (ret == NULL)
- return NULL;
- ret[0] = 0;
- return ret;
- }
+ if (nr_values == 0)
+ goto ok;
/* Arbitrarily limit the number of values we will ever deal with. */
if (nr_values > 100000) {
errno = ERANGE;
- return NULL;
+ goto error;
}
+ /* Preallocate space for the values. */
+ if (grow_offset_list (&values, nr_values) == -1)
+ goto error;
+
/* Get the value list and check it looks reasonable. */
size_t vlist_offset = le32toh (nk->vallist);
vlist_offset += 0x1000;
fprintf (stderr, "hivex_node_values: returning EFAULT because value list is not a valid block (0x%zx)\n",
vlist_offset);
errno = EFAULT;
- return NULL;
+ goto error;
}
+ if (add_to_offset_list (&blocks, vlist_offset) == -1)
+ goto error;
+
struct ntreg_value_list *vlist =
(struct ntreg_value_list *) (h->addr + vlist_offset);
fprintf (stderr, "hivex_node_values: returning EFAULT because value list is too long (%zu, %zu)\n",
nr_values, len);
errno = EFAULT;
- return NULL;
+ goto error;
}
- /* Allocate return array and copy values in. */
- ret = malloc ((1 + nr_values) * sizeof (hive_node_h));
- if (ret == NULL)
- return NULL;
-
size_t i;
for (i = 0; i < nr_values; ++i) {
hive_node_h value = vlist->offset[i];
fprintf (stderr, "hivex_node_values: returning EFAULT because value is not a valid block (0x%zx)\n",
value);
errno = EFAULT;
- free (ret);
- return NULL;
+ goto error;
}
- ret[i] = value;
+ if (add_to_offset_list (&values, value) == -1)
+ goto error;
}
- ret[i] = 0;
- return ret;
+ ok:
+ *values_ret = return_offset_list (&values);
+ *blocks_ret = return_offset_list (&blocks);
+ if (!*values_ret || !*blocks_ret)
+ goto error;
+ return 0;
+
+ error:
+ free_offset_list (&values);
+ free_offset_list (&blocks);
+ return -1;
+}
+
+hive_value_h *
+hivex_node_values (hive_h *h, hive_node_h node)
+{
+ hive_value_h *values;
+ size_t *blocks;
+
+ if (get_values (h, node, &values, &blocks) == -1)
+ return NULL;
+
+ free (blocks);
+ return values;
}
/* Very inefficient, but at least having a separate API call
return ret;
}
- size_t data_offset = vk->data_offset;
+ size_t data_offset = le32toh (vk->data_offset);
data_offset += 0x1000;
if (!IS_VALID_BLOCK (h, data_offset)) {
if (h->msglvl >= 2)
/* Check that the declared size isn't larger than the block its in. */
size_t blen = block_len (h, data_offset, NULL);
- if (len > blen) {
+ if (len > blen - 4 /* subtract 4 for block header */) {
if (h->msglvl >= 2)
fprintf (stderr, "hivex_value_value: returning EFAULT because data is longer than its block (data 0x%zx, data len %zu, block len %zu)\n",
data_offset, len, blen);
return ret;
}
+/*----------------------------------------------------------------------
+ * Visiting.
+ */
+
int
hivex_visit (hive_h *h, const struct hivex_visitor *visitor, size_t len,
void *opaque, int flags)
free_strings (strs);
return ret;
}
+
+/*----------------------------------------------------------------------
+ * Writing.
+ */
+
+/* Allocate an hbin (page), extending the malloc'd space if necessary,
+ * and updating the hive handle fields (but NOT the hive disk header
+ * -- the hive disk header is updated when we commit). This function
+ * also extends the bitmap if necessary.
+ *
+ * 'allocation_hint' is the size of the block allocation we would like
+ * to make. Normally registry blocks are very small (avg 50 bytes)
+ * and are contained in standard-sized pages (4KB), but the registry
+ * can support blocks which are larger than a standard page, in which
+ * case it creates a page of 8KB, 12KB etc.
+ *
+ * Returns:
+ * > 0 : offset of first usable byte of new page (after page header)
+ * 0 : error (errno set)
+ */
+static size_t
+allocate_page (hive_h *h, size_t allocation_hint)
+{
+ /* In almost all cases this will be 1. */
+ size_t nr_4k_pages =
+ 1 + (allocation_hint + sizeof (struct ntreg_hbin_page) - 1) / 4096;
+ assert (nr_4k_pages >= 1);
+
+ /* 'extend' is the number of bytes to extend the file by. Note that
+ * hives found in the wild often contain slack between 'endpages'
+ * and the actual end of the file, so we don't always need to make
+ * the file larger.
+ */
+ ssize_t extend = h->endpages + nr_4k_pages * 4096 - h->size;
+
+ if (h->msglvl >= 2) {
+ fprintf (stderr, "allocate_page: current endpages = 0x%zx, current size = 0x%zx\n",
+ h->endpages, h->size);
+ fprintf (stderr, "allocate_page: extending file by %zd bytes (<= 0 if no extension)\n",
+ extend);
+ }
+
+ if (extend > 0) {
+ size_t oldsize = h->size;
+ size_t newsize = h->size + extend;
+ char *newaddr = realloc (h->addr, newsize);
+ if (newaddr == NULL)
+ return 0;
+
+ size_t oldbitmapsize = 1 + oldsize / 32;
+ size_t newbitmapsize = 1 + newsize / 32;
+ char *newbitmap = realloc (h->bitmap, newbitmapsize);
+ if (newbitmap == NULL) {
+ free (newaddr);
+ return 0;
+ }
+
+ h->addr = newaddr;
+ h->size = newsize;
+ h->bitmap = newbitmap;
+
+ memset (h->addr + oldsize, 0, newsize - oldsize);
+ memset (h->bitmap + oldbitmapsize, 0, newbitmapsize - oldbitmapsize);
+ }
+
+ size_t offset = h->endpages;
+ h->endpages += nr_4k_pages * 4096;
+
+ if (h->msglvl >= 2)
+ fprintf (stderr, "allocate_page: new endpages = 0x%zx, new size = 0x%zx\n",
+ h->endpages, h->size);
+
+ /* Write the hbin header. */
+ struct ntreg_hbin_page *page =
+ (struct ntreg_hbin_page *) (h->addr + offset);
+ page->magic[0] = 'h';
+ page->magic[1] = 'b';
+ page->magic[2] = 'i';
+ page->magic[3] = 'n';
+ page->offset_first = htole32 (offset - 0x1000);
+ page->page_size = htole32 (nr_4k_pages * 4096);
+ memset (page->unknown, 0, sizeof (page->unknown));
+
+ if (h->msglvl >= 2)
+ fprintf (stderr, "allocate_page: new page at 0x%zx\n", offset);
+
+ /* Offset of first usable byte after the header. */
+ return offset + sizeof (struct ntreg_hbin_page);
+}
+
+/* Allocate a single block, first allocating an hbin (page) at the end
+ * of the current file if necessary. NB. To keep the implementation
+ * simple and more likely to be correct, we do not reuse existing free
+ * blocks.
+ *
+ * seg_len is the size of the block (this INCLUDES the block header).
+ * The header of the block is initialized to -seg_len (negative to
+ * indicate used). id[2] is the block ID (type), eg. "nk" for nk-
+ * record. The block bitmap is updated to show this block as valid.
+ * The rest of the contents of the block will be zero.
+ *
+ * Returns:
+ * > 0 : offset of new block
+ * 0 : error (errno set)
+ */
+static size_t
+allocate_block (hive_h *h, size_t seg_len, const char id[2])
+{
+ if (!h->writable) {
+ errno = EROFS;
+ return 0;
+ }
+
+ if (seg_len < 4) {
+ /* The caller probably forgot to include the header. Note that
+ * value lists have no ID field, so seg_len == 4 would be possible
+ * for them, albeit unusual.
+ */
+ if (h->msglvl >= 2)
+ fprintf (stderr, "allocate_block: refusing too small allocation (%zu), returning ERANGE\n",
+ seg_len);
+ errno = ERANGE;
+ return 0;
+ }
+
+ /* Refuse really large allocations. */
+ if (seg_len > 1000000) {
+ if (h->msglvl >= 2)
+ fprintf (stderr, "allocate_block: refusing large allocation (%zu), returning ERANGE\n",
+ seg_len);
+ errno = ERANGE;
+ return 0;
+ }
+
+ /* Round up allocation to multiple of 8 bytes. All blocks must be
+ * on an 8 byte boundary.
+ */
+ seg_len = (seg_len + 7) & ~7;
+
+ /* Allocate a new page if necessary. */
+ if (h->endblocks == 0 || h->endblocks + seg_len > h->endpages) {
+ size_t newendblocks = allocate_page (h, seg_len);
+ if (newendblocks == 0)
+ return 0;
+ h->endblocks = newendblocks;
+ }
+
+ size_t offset = h->endblocks;
+
+ if (h->msglvl >= 2)
+ fprintf (stderr, "allocate_block: new block at 0x%zx, size %zu\n",
+ offset, seg_len);
+
+ struct ntreg_hbin_block *blockhdr =
+ (struct ntreg_hbin_block *) (h->addr + offset);
+
+ blockhdr->seg_len = htole32 (- (int32_t) seg_len);
+ if (id[0] && id[1] && seg_len >= 6) {
+ blockhdr->id[0] = id[0];
+ blockhdr->id[1] = id[1];
+ }
+
+ h->endblocks += seg_len;
+
+ /* If there is space after the last block in the last page, then we
+ * have to put a dummy free block header here to mark the rest of
+ * the page as free.
+ */
+ ssize_t rem = h->endpages - h->endblocks;
+ if (rem > 0) {
+ if (h->msglvl >= 2)
+ fprintf (stderr, "allocate_block: marking remainder of page free starting at 0x%zx, size %zd\n",
+ h->endblocks, rem);
+
+ assert (rem >= 4);
+
+ blockhdr = (struct ntreg_hbin_block *) (h->addr + h->endblocks);
+ blockhdr->seg_len = htole32 ((int32_t) rem);
+ }
+
+ return offset;
+}
+
+/* 'offset' must point to a valid, used block. This function marks
+ * the block unused (by updating the seg_len field) and invalidates
+ * the bitmap. It does NOT do this recursively, so to avoid creating
+ * unreachable used blocks, callers may have to recurse over the hive
+ * structures. Also callers must ensure there are no references to
+ * this block from other parts of the hive.
+ */
+static void
+mark_block_unused (hive_h *h, size_t offset)
+{
+ assert (h->writable);
+ assert (IS_VALID_BLOCK (h, offset));
+
+ struct ntreg_hbin_block *blockhdr =
+ (struct ntreg_hbin_block *) (h->addr + offset);
+
+ size_t seg_len = block_len (h, offset, NULL);
+ blockhdr->seg_len = htole32 (seg_len);
+
+ BITMAP_CLR (h->bitmap, offset);
+}
+
+/* Delete all existing values at this node. */
+static int
+delete_values (hive_h *h, hive_node_h node)
+{
+ assert (h->writable);
+
+ hive_value_h *values;
+ size_t *blocks;
+ if (get_values (h, node, &values, &blocks) == -1)
+ return -1;
+
+ size_t i;
+ for (i = 0; blocks[i] != 0; ++i)
+ mark_block_unused (h, blocks[i]);
+
+ free (blocks);
+
+ for (i = 0; values[i] != 0; ++i) {
+ struct ntreg_vk_record *vk =
+ (struct ntreg_vk_record *) (h->addr + values[i]);
+
+ size_t len;
+ len = le32toh (vk->data_len);
+ if (len == 0x80000000) /* special case */
+ len = 4;
+ len &= 0x7fffffff;
+
+ if (len > 4) { /* non-inline, so remove data block */
+ size_t data_offset = le32toh (vk->data_offset);
+ data_offset += 0x1000;
+ mark_block_unused (h, data_offset);
+ }
+
+ /* remove vk record */
+ mark_block_unused (h, values[i]);
+ }
+
+ free (values);
+
+ struct ntreg_nk_record *nk = (struct ntreg_nk_record *) (h->addr + node);
+ nk->nr_values = htole32 (0);
+ nk->vallist = htole32 (0xffffffff);
+
+ return 0;
+}
+
+int
+hivex_commit (hive_h *h, const char *filename, int flags)
+{
+ if (flags != 0) {
+ errno = EINVAL;
+ return -1;
+ }
+
+ if (!h->writable) {
+ errno = EROFS;
+ return -1;
+ }
+
+ filename = filename ? : h->filename;
+ int fd = open (filename, O_WRONLY|O_CREAT|O_TRUNC|O_NOCTTY, 0666);
+ if (fd == -1)
+ return -1;
+
+ /* Update the header fields. */
+ uint32_t sequence = le32toh (h->hdr->sequence1);
+ sequence++;
+ h->hdr->sequence1 = htole32 (sequence);
+ h->hdr->sequence2 = htole32 (sequence);
+ /* XXX Ought to update h->hdr->last_modified. */
+ h->hdr->blocks = htole32 (h->endpages - 0x1000);
+
+ /* Recompute header checksum. */
+ uint32_t sum = header_checksum (h);
+ h->hdr->csum = htole32 (sum);
+
+ if (h->msglvl >= 2)
+ fprintf (stderr, "hivex_commit: new header checksum: 0x%x\n", sum);
+
+ if (full_write (fd, h->addr, h->size) != h->size) {
+ int err = errno;
+ close (fd);
+ errno = err;
+ return -1;
+ }
+
+ if (close (fd) == -1)
+ return -1;
+
+ return 0;
+}
+
+int
+hivex_node_set_values (hive_h *h, hive_node_h node,
+ size_t nr_values, const hive_set_value *values,
+ int flags)
+{
+ if (!h->writable) {
+ errno = EROFS;
+ return -1;
+ }
+
+ if (!IS_VALID_BLOCK (h, node) || !BLOCK_ID_EQ (h, node, "nk")) {
+ errno = EINVAL;
+ return -1;
+ }
+
+ /* Delete all existing values. */
+ if (delete_values (h, node) == -1)
+ return -1;
+
+ if (nr_values == 0)
+ return 0;
+
+ /* Allocate value list node. Value lists have no id field. */
+ static const char nul_id[2] = { 0, 0 };
+ size_t seg_len =
+ sizeof (struct ntreg_value_list) + (nr_values - 1) * sizeof (uint32_t);
+ size_t vallist_offs = allocate_block (h, seg_len, nul_id);
+ if (vallist_offs == 0)
+ return -1;
+
+ struct ntreg_nk_record *nk = (struct ntreg_nk_record *) (h->addr + node);
+ nk->nr_values = htole32 (nr_values);
+ nk->vallist = htole32 (vallist_offs - 0x1000);
+
+ struct ntreg_value_list *vallist =
+ (struct ntreg_value_list *) (h->addr + vallist_offs);
+
+ size_t i;
+ for (i = 0; i < nr_values; ++i) {
+ /* Allocate vk record to store this (key, value) pair. */
+ static const char vk_id[2] = { 'v', 'k' };
+ seg_len = sizeof (struct ntreg_vk_record) + strlen (values[i].key);
+ size_t vk_offs = allocate_block (h, seg_len, vk_id);
+ if (vk_offs == 0)
+ return -1;
+
+ vallist->offset[i] = htole32 (vk_offs - 0x1000);
+
+ struct ntreg_vk_record *vk = (struct ntreg_vk_record *) (h->addr + vk_offs);
+ size_t name_len = strlen (values[i].key);
+ vk->name_len = htole16 (name_len);
+ strcpy (vk->name, values[i].key);
+ vk->data_type = htole32 (values[i].t);
+ vk->data_len = htole16 (values[i].len);
+ vk->flags = name_len == 0 ? 0 : 1;
+
+ if (values[i].len <= 4) /* Store data inline. */
+ memcpy (&vk->data_offset, values[i].value, values[i].len);
+ else {
+ size_t offs = allocate_block (h, values[i].len + 4, nul_id);
+ if (offs == 0)
+ return -1;
+ memcpy (h->addr + offs + 4, values[i].value, values[i].len);
+ vk->data_offset = htole32 (offs - 0x1000);
+ }
+
+ if (name_len * 2 > le32toh (nk->max_vk_name_len))
+ nk->max_vk_name_len = htole32 (name_len * 2);
+ if (values[i].len > le32toh (nk->max_vk_data_len))
+ nk->max_vk_data_len = htole32 (values[i].len);
+ }
+
+ return 0;
+}