/*
- * reparse.c
- *
- * Handle reparse data.
+ * reparse.c - Handle reparse data.
*/
/*
* along with wimlib; if not, see http://www.gnu.org/licenses/.
*/
-#include "dentry.h"
-#include "buffer_io.h"
-#include "lookup_table.h"
-#include "sha1.h"
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include "wimlib/assert.h"
+#include "wimlib/compiler.h"
+#include "wimlib/endianness.h"
+#include "wimlib/dentry.h"
+#include "wimlib/encoding.h"
+#include "wimlib/error.h"
+#include "wimlib/lookup_table.h"
+#include "wimlib/reparse.h"
+#include "wimlib/resource.h"
+
+#ifdef __WIN32__
+# include "wimlib/win32.h" /* for win32_get_file_and_vol_ids() */
+#endif
+
+#ifdef HAVE_ALLOCA_H
+# include <alloca.h>
+#endif
#include <errno.h>
+#include <stdlib.h>
+
+/* On-disk format of a symbolic link (WIM_IO_REPARSE_TAG_SYMLINK) or junction
+ * point (WIM_IO_REPARSE_TAG_MOUNT_POINT) reparse data buffer. */
+struct reparse_buffer_disk {
+ le32 rptag;
+ le16 rpdatalen;
+ le16 rpreserved;
+ le16 substitute_name_offset;
+ le16 substitute_name_nbytes;
+ le16 print_name_offset;
+ le16 print_name_nbytes;
+ union {
+ struct {
+ le32 rpflags;
+ u8 data[REPARSE_POINT_MAX_SIZE - 20];
+ } _packed_attribute symlink;
+ struct {
+ u8 data[REPARSE_POINT_MAX_SIZE - 16];
+ } _packed_attribute junction;
+ };
+} _packed_attribute;
static const utf16lechar volume_junction_prefix[11] = {
cpu_to_le16('\\'),
* Return value is:
*
* Non-negative integer:
- * The name is an absolute symbolic link in one of several formats,
- * and the return value is the number of UTF-16LE characters that need to
- * be advanced to reach a simple "absolute" path starting with a backslash
- * (i.e. skip over \??\ and/or drive letter)
+ * The name is an absolute symbolic link in one of several formats,
+ * and the return value is the number of UTF-16LE characters that need to
+ * be advanced to reach a simple "absolute" path starting with a backslash
+ * (i.e. skip over \??\ and/or drive letter)
* Negative integer:
* SUBST_NAME_IS_VOLUME_JUNCTION:
- * The name is a volume junction.
+ * The name is a volume junction.
* SUBST_NAME_IS_RELATIVE_LINK:
- * The name is a relative symbolic link.
+ * The name is a relative symbolic link.
* SUBST_NAME_IS_UNKNOWN:
* The name does not appear to be a valid symbolic link, junction,
* or mount point.
* description of the format of the reparse point buffers.
*/
int
-parse_reparse_data(const u8 *rpbuf, u16 rpbuflen, struct reparse_data *rpdata)
+parse_reparse_data(const u8 * restrict rpbuf, u16 rpbuflen,
+ struct reparse_data * restrict rpdata)
{
- const u8 *p = rpbuf;
u16 substitute_name_offset;
u16 print_name_offset;
+ const struct reparse_buffer_disk *rpbuf_disk =
+ (const struct reparse_buffer_disk*)rpbuf;
+ const u8 *data;
memset(rpdata, 0, sizeof(*rpdata));
if (rpbuflen < 16)
goto out_invalid;
- p = get_u32(p, &rpdata->rptag);
+ rpdata->rptag = le32_to_cpu(rpbuf_disk->rptag);
wimlib_assert(rpdata->rptag == WIM_IO_REPARSE_TAG_SYMLINK ||
rpdata->rptag == WIM_IO_REPARSE_TAG_MOUNT_POINT);
- p = get_u16(p, &rpdata->rpdatalen);
- p = get_u16(p, &rpdata->rpreserved);
- p = get_u16(p, &substitute_name_offset);
- p = get_u16(p, &rpdata->substitute_name_nbytes);
- p = get_u16(p, &print_name_offset);
- p = get_u16(p, &rpdata->print_name_nbytes);
+ rpdata->rpdatalen = le16_to_cpu(rpbuf_disk->rpdatalen);
+ rpdata->rpreserved = le16_to_cpu(rpbuf_disk->rpreserved);
+ substitute_name_offset = le16_to_cpu(rpbuf_disk->substitute_name_offset);
+ rpdata->substitute_name_nbytes = le16_to_cpu(rpbuf_disk->substitute_name_nbytes);
+ print_name_offset = le16_to_cpu(rpbuf_disk->print_name_offset);
+ rpdata->print_name_nbytes = le16_to_cpu(rpbuf_disk->print_name_nbytes);
+
+ if ((substitute_name_offset & 1) | (print_name_offset & 1) |
+ (rpdata->substitute_name_nbytes & 1) | (rpdata->print_name_nbytes & 1))
+ {
+ /* Names would be unaligned... */
+ goto out_invalid;
+ }
+
if (rpdata->rptag == WIM_IO_REPARSE_TAG_SYMLINK) {
if (rpbuflen < 20)
goto out_invalid;
- p = get_u32(p, &rpdata->rpflags);
+ rpdata->rpflags = le32_to_cpu(rpbuf_disk->symlink.rpflags);
+ data = rpbuf_disk->symlink.data;
+ } else {
+ data = rpbuf_disk->junction.data;
}
if ((size_t)substitute_name_offset + rpdata->substitute_name_nbytes +
- (p - rpbuf) > rpbuflen)
+ (data - rpbuf) > rpbuflen)
goto out_invalid;
if ((size_t)print_name_offset + rpdata->print_name_nbytes +
- (p - rpbuf) > rpbuflen)
+ (data - rpbuf) > rpbuflen)
goto out_invalid;
- rpdata->substitute_name = (utf16lechar*)&p[substitute_name_offset];
- rpdata->print_name = (utf16lechar*)&p[print_name_offset];
+ rpdata->substitute_name = (utf16lechar*)&data[substitute_name_offset];
+ rpdata->print_name = (utf16lechar*)&data[print_name_offset];
return 0;
out_invalid:
ERROR("Invalid reparse data");
* at least REPARSE_POINT_MAX_SIZE bytes long.
*/
int
-make_reparse_buffer(const struct reparse_data *rpdata, u8 *rpbuf)
+make_reparse_buffer(const struct reparse_data * restrict rpdata,
+ u8 * restrict rpbuf,
+ u16 * restrict rpbuflen_ret)
{
- u8 *p = rpbuf;
-
- p = put_u32(p, rpdata->rptag);
- p += 2; /* We set ReparseDataLength later */
- p = put_u16(p, rpdata->rpreserved);
- p = put_u16(p, 0); /* substitute name offset */
- p = put_u16(p, rpdata->substitute_name_nbytes); /* substitute name nbytes */
- p = put_u16(p, rpdata->substitute_name_nbytes + 2); /* print name offset */
- p = put_u16(p, rpdata->print_name_nbytes); /* print name nbytes */
- if (rpdata->rptag == WIM_IO_REPARSE_TAG_SYMLINK)
- p = put_u32(p, rpdata->rpflags);
+ struct reparse_buffer_disk *rpbuf_disk =
+ (struct reparse_buffer_disk*)rpbuf;
+ u8 *data;
+
+ rpbuf_disk->rptag = cpu_to_le32(rpdata->rptag);
+ rpbuf_disk->rpreserved = cpu_to_le16(rpdata->rpreserved);
+ rpbuf_disk->substitute_name_offset = cpu_to_le16(0);
+ rpbuf_disk->substitute_name_nbytes = cpu_to_le16(rpdata->substitute_name_nbytes);
+ rpbuf_disk->print_name_offset = cpu_to_le16(rpdata->substitute_name_nbytes + 2);
+ rpbuf_disk->print_name_nbytes = cpu_to_le16(rpdata->print_name_nbytes);
+
+ if (rpdata->rptag == WIM_IO_REPARSE_TAG_SYMLINK) {
+ rpbuf_disk->symlink.rpflags = cpu_to_le32(rpdata->rpflags);
+ data = rpbuf_disk->symlink.data;
+ } else {
+ data = rpbuf_disk->junction.data;
+ }
+
/* We null-terminate the substitute and print names, although this may
* not be strictly necessary. Note that the byte counts should not
* include the null terminators. */
- if (p + rpdata->substitute_name_nbytes +
+ if (data + rpdata->substitute_name_nbytes +
rpdata->print_name_nbytes +
2 * sizeof(utf16lechar) - rpbuf > REPARSE_POINT_MAX_SIZE)
{
ERROR("Reparse data is too long!");
return WIMLIB_ERR_INVALID_REPARSE_DATA;
}
- p = put_bytes(p, rpdata->substitute_name_nbytes, rpdata->substitute_name);
- p = put_u16(p, 0);
- p = put_bytes(p, rpdata->print_name_nbytes, rpdata->print_name);
- p = put_u16(p, 0);
- put_u16(rpbuf + 4, p - rpbuf - 8); /* Set ReparseDataLength */
+ data = mempcpy(data, rpdata->substitute_name, rpdata->substitute_name_nbytes);
+ *(utf16lechar*)data = cpu_to_le16(0);
+ data += 2;
+ data = mempcpy(data, rpdata->print_name, rpdata->print_name_nbytes);
+ *(utf16lechar*)data = cpu_to_le16(0);
+ data += 2;
+ rpbuf_disk->rpdatalen = cpu_to_le16(data - rpbuf - 8);
+ *rpbuflen_ret = data - rpbuf;
return 0;
}
* buffer returned by this function.
*/
int
-wim_inode_get_reparse_data(const struct wim_inode *inode, u8 *rpbuf)
+wim_inode_get_reparse_data(const struct wim_inode * restrict inode,
+ u8 * restrict rpbuf,
+ u16 * restrict rpbuflen_ret,
+ struct wim_lookup_table_entry *lte_override)
{
struct wim_lookup_table_entry *lte;
int ret;
+ struct reparse_buffer_disk *rpbuf_disk;
+ u16 rpdatalen;
wimlib_assert(inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT);
- lte = inode_unnamed_lte_resolved(inode);
- if (!lte) {
- ERROR("Reparse point has no reparse data!");
- return WIMLIB_ERR_INVALID_REPARSE_DATA;
+ if (!lte_override) {
+ lte = inode_unnamed_lte_resolved(inode);
+ if (!lte) {
+ ERROR("Reparse point has no reparse data!");
+ return WIMLIB_ERR_INVALID_REPARSE_DATA;
+ }
+ } else {
+ lte = lte_override;
}
- if (wim_resource_size(lte) > REPARSE_POINT_MAX_SIZE - 8) {
+
+ if (lte->size > REPARSE_POINT_MAX_SIZE - 8) {
ERROR("Reparse data is too long!");
return WIMLIB_ERR_INVALID_REPARSE_DATA;
}
+ rpdatalen = lte->size;
/* Read the data from the WIM file */
- ret = read_full_resource_into_buf(lte, rpbuf + 8);
+ ret = read_full_stream_into_buf(lte, rpbuf + 8);
if (ret)
return ret;
/* Reconstruct the first 8 bytes of the reparse point buffer */
+ rpbuf_disk = (struct reparse_buffer_disk*)rpbuf;
/* ReparseTag */
- put_u32(rpbuf, inode->i_reparse_tag);
+ rpbuf_disk->rptag = cpu_to_le32(inode->i_reparse_tag);
/* ReparseDataLength */
- put_u16(rpbuf + 4, wim_resource_size(lte));
+ rpbuf_disk->rpdatalen = cpu_to_le16(rpdatalen);
/* ReparseReserved
* XXX this could be one of the unknown fields in the WIM dentry. */
- put_u16(rpbuf + 6, 0);
+ rpbuf_disk->rpreserved = cpu_to_le16(0);
+
+ *rpbuflen_ret = rpdatalen + 8;
return 0;
}
* argument is swapped out with the `struct wim_inode' for a reparse point, and
* on failure a negated error code is returned rather than -1 with errno set. */
ssize_t
-wim_inode_readlink(const struct wim_inode *inode, char *buf, size_t bufsize)
+wim_inode_readlink(const struct wim_inode * restrict inode,
+ char * restrict buf, size_t bufsize,
+ struct wim_lookup_table_entry *lte_override)
{
int ret;
- u8 rpbuf[REPARSE_POINT_MAX_SIZE];
- u16 rpdatalen;
+ struct reparse_buffer_disk rpbuf_disk _aligned_attribute(8);
struct reparse_data rpdata;
char *link_target;
char *translated_target;
size_t link_target_len;
+ u16 rpbuflen;
wimlib_assert(inode_is_symlink(inode));
- if (wim_inode_get_reparse_data(inode, rpbuf))
+ if (wim_inode_get_reparse_data(inode, (u8*)&rpbuf_disk, &rpbuflen,
+ lte_override))
return -EIO;
- get_u16(rpbuf + 4, &rpdatalen);
-
- if (parse_reparse_data(rpbuf, rpdatalen + 8, &rpdata))
+ if (parse_reparse_data((const u8*)&rpbuf_disk, rpbuflen, &rpdata))
return -EIO;
ret = utf16le_to_tstr(rpdata.substitute_name,
case SUBST_NAME_IS_UNKNOWN:
ERROR("Can't understand reparse point "
"substitute name \"%s\"", link_target);
- return -EIO;
+ ret = -EIO;
+ goto out_free_link_target;
default:
translated_target += ret;
link_target_len -= ret;
ret = link_target_len;
}
memcpy(buf, translated_target, link_target_len);
+out_free_link_target:
FREE(link_target);
return ret;
}
-#ifdef HAVE_ALLOCA_H
-# include <alloca.h>
-#endif
-
int
wim_inode_set_symlink(struct wim_inode *inode,
const char *target,
struct wim_lookup_table *lookup_table)
{
- u8 rpbuf[REPARSE_POINT_MAX_SIZE];
- u16 rpdatalen;
+ struct reparse_buffer_disk rpbuf_disk _aligned_attribute(8);
struct reparse_data rpdata;
static const char abs_subst_name_prefix[12] = "\\\0?\0?\0\\\0C\0:\0";
static const char abs_print_name_prefix[4] = "C\0:\0";
utf16lechar *name_utf16le;
size_t name_utf16le_nbytes;
int ret;
+ u16 rpbuflen;
DEBUG("Creating reparse point data buffer for UNIX "
"symlink target \"%s\"", target);
* ways to provide Windows paths.)
*
* To change a UNIX relative symbolic link to Windows format, we only
- * need to translate it to UTF-16LE and replace backslashes with forward
- * slashes. We do not make any attempt to handle filename character
+ * need to translate it to UTF-16LE and replace forward slashes with
+ * backslashes. We do not make any attempt to handle filename character
* problems, such as a link target that itself contains backslashes on
* UNIX. Then, for these relative links, we set the reparse header
* @flags field to SYMBOLIC_LINK_RELATIVE.
rpdata.rpflags = SYMBOLIC_LINK_RELATIVE;
}
- ret = make_reparse_buffer(&rpdata, rpbuf);
+ ret = make_reparse_buffer(&rpdata, (u8*)&rpbuf_disk, &rpbuflen);
if (ret == 0) {
- get_u16(rpbuf + 4, &rpdatalen);
- ret = inode_set_unnamed_stream(inode, rpbuf + 8, rpdatalen,
+ ret = inode_set_unnamed_stream(inode,
+ (u8*)&rpbuf_disk + 8,
+ rpbuflen - 8,
lookup_table);
}
FREE(name_utf16le);
#endif /* !defined(__WIN32__) */
+/* is_rp_path_separator() - characters treated as path separators in absolute
+ * symbolic link targets */
+
#ifdef __WIN32__
-# include "win32.h"
-# define RP_PATH_SEPARATOR L'\\'
# define is_rp_path_separator(c) ((c) == L'\\' || (c) == L'/')
# define os_get_ino_and_dev win32_get_file_and_vol_ids
#else
-# define RP_PATH_SEPARATOR '/'
# define is_rp_path_separator(c) ((c) == '/')
# define os_get_ino_and_dev unix_get_ino_and_dev
#endif
/* Link points inside capture root. Return abbreviated
* path. */
if (*p == T('\0'))
- *(p - 1) = RP_PATH_SEPARATOR;
+ *(p - 1) = OS_PREFERRED_PATH_SEPARATOR;
while (p - 1 >= dest && is_rp_path_separator(*(p - 1)))
p--;
#ifdef __WIN32__