#endif
#include "wimlib/assert.h"
-#include "wimlib/buffer_io.h"
+#include "wimlib/compiler.h"
+#include "wimlib/endianness.h"
#include "wimlib/dentry.h"
#include "wimlib/encoding.h"
#include "wimlib/error.h"
#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('\\'),
cpu_to_le16('\\'),
* 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)
{
- 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);
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;
int ret;
+ struct reparse_buffer_disk *rpbuf_disk;
+ u16 rpdatalen;
wimlib_assert(inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT);
ERROR("Reparse point has no reparse data!");
return WIMLIB_ERR_INVALID_REPARSE_DATA;
}
+
if (wim_resource_size(lte) > REPARSE_POINT_MAX_SIZE - 8) {
ERROR("Reparse data is too long!");
return WIMLIB_ERR_INVALID_REPARSE_DATA;
}
+ rpdatalen = wim_resource_size(lte);
/* Read the data from the WIM file */
ret = read_full_resource_into_buf(lte, rpbuf + 8);
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)
{
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))
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;
}
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";
rpdata.rpflags = SYMBOLIC_LINK_RELATIVE;
}
- ret = make_reparse_buffer(&rpdata, rpbuf);
+ ret = make_reparse_buffer(&rpdata, (u8*)&rpbuf_disk);
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,
+ le16_to_cpu(rpbuf_disk.rpdatalen),
lookup_table);
}
FREE(name_utf16le);
git://wimlib.net / wimlib / blobdiff