u-boot/lib/efi_loader/efi_file.c
Heinrich Schuchardt f62be16ddb efi_loader: unaligned access in efi_file_from_path()
The device path structure is packed. So no assumption on the alignment is
possible. Copy the file name in efi_file_from_path() to assure there is no
unaligned access.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2019-07-16 22:17:23 +00:00

811 lines
18 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* EFI utils
*
* Copyright (c) 2017 Rob Clark
*/
#include <common.h>
#include <charset.h>
#include <efi_loader.h>
#include <malloc.h>
#include <mapmem.h>
#include <fs.h>
/* GUID for file system information */
const efi_guid_t efi_file_system_info_guid = EFI_FILE_SYSTEM_INFO_GUID;
struct file_system {
struct efi_simple_file_system_protocol base;
struct efi_device_path *dp;
struct blk_desc *desc;
int part;
};
#define to_fs(x) container_of(x, struct file_system, base)
struct file_handle {
struct efi_file_handle base;
struct file_system *fs;
loff_t offset; /* current file position/cursor */
int isdir;
/* for reading a directory: */
struct fs_dir_stream *dirs;
struct fs_dirent *dent;
char path[0];
};
#define to_fh(x) container_of(x, struct file_handle, base)
static const struct efi_file_handle efi_file_handle_protocol;
static char *basename(struct file_handle *fh)
{
char *s = strrchr(fh->path, '/');
if (s)
return s + 1;
return fh->path;
}
static int set_blk_dev(struct file_handle *fh)
{
return fs_set_blk_dev_with_part(fh->fs->desc, fh->fs->part);
}
/**
* is_dir() - check if file handle points to directory
*
* We assume that set_blk_dev(fh) has been called already.
*
* @fh: file handle
* Return: true if file handle points to a directory
*/
static int is_dir(struct file_handle *fh)
{
struct fs_dir_stream *dirs;
dirs = fs_opendir(fh->path);
if (!dirs)
return 0;
fs_closedir(dirs);
return 1;
}
/*
* Normalize a path which may include either back or fwd slashes,
* double slashes, . or .. entries in the path, etc.
*/
static int sanitize_path(char *path)
{
char *p;
/* backslash to slash: */
p = path;
while ((p = strchr(p, '\\')))
*p++ = '/';
/* handle double-slashes: */
p = path;
while ((p = strstr(p, "//"))) {
char *src = p + 1;
memmove(p, src, strlen(src) + 1);
}
/* handle extra /.'s */
p = path;
while ((p = strstr(p, "/."))) {
/*
* You'd be tempted to do this *after* handling ".."s
* below to avoid having to check if "/." is start of
* a "/..", but that won't have the correct results..
* for example, "/foo/./../bar" would get resolved to
* "/foo/bar" if you did these two passes in the other
* order
*/
if (p[2] == '.') {
p += 2;
continue;
}
char *src = p + 2;
memmove(p, src, strlen(src) + 1);
}
/* handle extra /..'s: */
p = path;
while ((p = strstr(p, "/.."))) {
char *src = p + 3;
p--;
/* find beginning of previous path entry: */
while (true) {
if (p < path)
return -1;
if (*p == '/')
break;
p--;
}
memmove(p, src, strlen(src) + 1);
}
return 0;
}
/**
* efi_create_file() - create file or directory
*
* @fh: file handle
* @attributes: attributes for newly created file
* Returns: 0 for success
*/
static int efi_create_file(struct file_handle *fh, u64 attributes)
{
loff_t actwrite;
void *buffer = &actwrite;
if (attributes & EFI_FILE_DIRECTORY)
return fs_mkdir(fh->path);
else
return fs_write(fh->path, map_to_sysmem(buffer), 0, 0,
&actwrite);
}
/**
* file_open() - open a file handle
*
* @fs: file system
* @parent: directory relative to which the file is to be opened
* @file_name: path of the file to be opened. '\', '.', or '..' may
* be used as modifiers. A leading backslash indicates an
* absolute path.
* @mode: bit mask indicating the access mode (read, write,
* create)
* @attributes: attributes for newly created file
* Returns: handle to the opened file or NULL
*/
static struct efi_file_handle *file_open(struct file_system *fs,
struct file_handle *parent, u16 *file_name, u64 mode,
u64 attributes)
{
struct file_handle *fh;
char f0[MAX_UTF8_PER_UTF16] = {0};
int plen = 0;
int flen = 0;
if (file_name) {
utf16_to_utf8((u8 *)f0, file_name, 1);
flen = u16_strlen(file_name);
}
/* we could have a parent, but also an absolute path: */
if (f0[0] == '\\') {
plen = 0;
} else if (parent) {
plen = strlen(parent->path) + 1;
}
/* +2 is for null and '/' */
fh = calloc(1, sizeof(*fh) + plen + (flen * MAX_UTF8_PER_UTF16) + 2);
fh->base = efi_file_handle_protocol;
fh->fs = fs;
if (parent) {
char *p = fh->path;
int exists;
if (plen > 0) {
strcpy(p, parent->path);
p += plen - 1;
*p++ = '/';
}
utf16_to_utf8((u8 *)p, file_name, flen);
if (sanitize_path(fh->path))
goto error;
/* check if file exists: */
if (set_blk_dev(fh))
goto error;
exists = fs_exists(fh->path);
/* fs_exists() calls fs_close(), so open file system again */
if (set_blk_dev(fh))
goto error;
if (!exists) {
if (!(mode & EFI_FILE_MODE_CREATE) ||
efi_create_file(fh, attributes))
goto error;
}
/* figure out if file is a directory: */
fh->isdir = is_dir(fh);
} else {
fh->isdir = 1;
strcpy(fh->path, "");
}
return &fh->base;
error:
free(fh);
return NULL;
}
static efi_status_t EFIAPI efi_file_open(struct efi_file_handle *file,
struct efi_file_handle **new_handle,
u16 *file_name, u64 open_mode, u64 attributes)
{
struct file_handle *fh = to_fh(file);
efi_status_t ret;
EFI_ENTRY("%p, %p, \"%ls\", %llx, %llu", file, new_handle,
file_name, open_mode, attributes);
/* Check parameters */
if (!file || !new_handle || !file_name) {
ret = EFI_INVALID_PARAMETER;
goto out;
}
if (open_mode != EFI_FILE_MODE_READ &&
open_mode != (EFI_FILE_MODE_READ | EFI_FILE_MODE_WRITE) &&
open_mode != (EFI_FILE_MODE_READ | EFI_FILE_MODE_WRITE |
EFI_FILE_MODE_CREATE)) {
ret = EFI_INVALID_PARAMETER;
goto out;
}
/*
* The UEFI spec requires that attributes are only set in create mode.
* The SCT does not care about this and sets EFI_FILE_DIRECTORY in
* read mode. EDK2 does not check that attributes are zero if not in
* create mode.
*
* So here we only check attributes in create mode and do not check
* that they are zero otherwise.
*/
if ((open_mode & EFI_FILE_MODE_CREATE) &&
(attributes & (EFI_FILE_READ_ONLY | ~EFI_FILE_VALID_ATTR))) {
ret = EFI_INVALID_PARAMETER;
goto out;
}
/* Open file */
*new_handle = file_open(fh->fs, fh, file_name, open_mode, attributes);
if (*new_handle) {
EFI_PRINT("file handle %p\n", *new_handle);
ret = EFI_SUCCESS;
} else {
ret = EFI_NOT_FOUND;
}
out:
return EFI_EXIT(ret);
}
static efi_status_t file_close(struct file_handle *fh)
{
fs_closedir(fh->dirs);
free(fh);
return EFI_SUCCESS;
}
static efi_status_t EFIAPI efi_file_close(struct efi_file_handle *file)
{
struct file_handle *fh = to_fh(file);
EFI_ENTRY("%p", file);
return EFI_EXIT(file_close(fh));
}
static efi_status_t EFIAPI efi_file_delete(struct efi_file_handle *file)
{
struct file_handle *fh = to_fh(file);
efi_status_t ret = EFI_SUCCESS;
EFI_ENTRY("%p", file);
if (set_blk_dev(fh) || fs_unlink(fh->path))
ret = EFI_WARN_DELETE_FAILURE;
file_close(fh);
return EFI_EXIT(ret);
}
static efi_status_t file_read(struct file_handle *fh, u64 *buffer_size,
void *buffer)
{
loff_t actread;
if (fs_read(fh->path, map_to_sysmem(buffer), fh->offset,
*buffer_size, &actread))
return EFI_DEVICE_ERROR;
*buffer_size = actread;
fh->offset += actread;
return EFI_SUCCESS;
}
static efi_status_t dir_read(struct file_handle *fh, u64 *buffer_size,
void *buffer)
{
struct efi_file_info *info = buffer;
struct fs_dirent *dent;
unsigned int required_size;
if (!fh->dirs) {
assert(fh->offset == 0);
fh->dirs = fs_opendir(fh->path);
if (!fh->dirs)
return EFI_DEVICE_ERROR;
}
/*
* So this is a bit awkward. Since fs layer is stateful and we
* can't rewind an entry, in the EFI_BUFFER_TOO_SMALL case below
* we might have to return without consuming the dent.. so we
* have to stash it for next call.
*/
if (fh->dent) {
dent = fh->dent;
fh->dent = NULL;
} else {
dent = fs_readdir(fh->dirs);
}
if (!dent) {
/* no more files in directory: */
/* workaround shim.efi bug/quirk.. as find_boot_csv()
* loops through directory contents, it initially calls
* read w/ zero length buffer to find out how much mem
* to allocate for the EFI_FILE_INFO, then allocates,
* and then calls a 2nd time. If we return size of
* zero the first time, it happily passes that to
* AllocateZeroPool(), and when that returns NULL it
* thinks it is EFI_OUT_OF_RESOURCES. So on first
* call return a non-zero size:
*/
if (*buffer_size == 0)
*buffer_size = sizeof(*info);
else
*buffer_size = 0;
return EFI_SUCCESS;
}
/* check buffer size: */
required_size = sizeof(*info) + 2 * (strlen(dent->name) + 1);
if (*buffer_size < required_size) {
*buffer_size = required_size;
fh->dent = dent;
return EFI_BUFFER_TOO_SMALL;
}
*buffer_size = required_size;
memset(info, 0, required_size);
info->size = required_size;
info->file_size = dent->size;
info->physical_size = dent->size;
if (dent->type == FS_DT_DIR)
info->attribute |= EFI_FILE_DIRECTORY;
ascii2unicode(info->file_name, dent->name);
fh->offset++;
return EFI_SUCCESS;
}
static efi_status_t EFIAPI efi_file_read(struct efi_file_handle *file,
efi_uintn_t *buffer_size, void *buffer)
{
struct file_handle *fh = to_fh(file);
efi_status_t ret = EFI_SUCCESS;
u64 bs;
EFI_ENTRY("%p, %p, %p", file, buffer_size, buffer);
if (!buffer_size || !buffer) {
ret = EFI_INVALID_PARAMETER;
goto error;
}
if (set_blk_dev(fh)) {
ret = EFI_DEVICE_ERROR;
goto error;
}
bs = *buffer_size;
if (fh->isdir)
ret = dir_read(fh, &bs, buffer);
else
ret = file_read(fh, &bs, buffer);
if (bs <= SIZE_MAX)
*buffer_size = bs;
else
*buffer_size = SIZE_MAX;
error:
return EFI_EXIT(ret);
}
static efi_status_t EFIAPI efi_file_write(struct efi_file_handle *file,
efi_uintn_t *buffer_size,
void *buffer)
{
struct file_handle *fh = to_fh(file);
efi_status_t ret = EFI_SUCCESS;
loff_t actwrite;
EFI_ENTRY("%p, %p, %p", file, buffer_size, buffer);
if (set_blk_dev(fh)) {
ret = EFI_DEVICE_ERROR;
goto error;
}
if (fs_write(fh->path, map_to_sysmem(buffer), fh->offset, *buffer_size,
&actwrite)) {
ret = EFI_DEVICE_ERROR;
goto error;
}
*buffer_size = actwrite;
fh->offset += actwrite;
error:
return EFI_EXIT(ret);
}
/**
* efi_file_getpos() - get current position in file
*
* This function implements the GetPosition service of the EFI file protocol.
* See the UEFI spec for details.
*
* @file: file handle
* @pos: pointer to file position
* Return: status code
*/
static efi_status_t EFIAPI efi_file_getpos(struct efi_file_handle *file,
u64 *pos)
{
efi_status_t ret = EFI_SUCCESS;
struct file_handle *fh = to_fh(file);
EFI_ENTRY("%p, %p", file, pos);
if (fh->isdir) {
ret = EFI_UNSUPPORTED;
goto out;
}
*pos = fh->offset;
out:
return EFI_EXIT(ret);
}
/**
* efi_file_setpos() - set current position in file
*
* This function implements the SetPosition service of the EFI file protocol.
* See the UEFI spec for details.
*
* @file: file handle
* @pos: new file position
* Return: status code
*/
static efi_status_t EFIAPI efi_file_setpos(struct efi_file_handle *file,
u64 pos)
{
struct file_handle *fh = to_fh(file);
efi_status_t ret = EFI_SUCCESS;
EFI_ENTRY("%p, %llu", file, pos);
if (fh->isdir) {
if (pos != 0) {
ret = EFI_UNSUPPORTED;
goto error;
}
fs_closedir(fh->dirs);
fh->dirs = NULL;
}
if (pos == ~0ULL) {
loff_t file_size;
if (set_blk_dev(fh)) {
ret = EFI_DEVICE_ERROR;
goto error;
}
if (fs_size(fh->path, &file_size)) {
ret = EFI_DEVICE_ERROR;
goto error;
}
pos = file_size;
}
fh->offset = pos;
error:
return EFI_EXIT(ret);
}
static efi_status_t EFIAPI efi_file_getinfo(struct efi_file_handle *file,
const efi_guid_t *info_type,
efi_uintn_t *buffer_size,
void *buffer)
{
struct file_handle *fh = to_fh(file);
efi_status_t ret = EFI_SUCCESS;
EFI_ENTRY("%p, %pUl, %p, %p", file, info_type, buffer_size, buffer);
if (!guidcmp(info_type, &efi_file_info_guid)) {
struct efi_file_info *info = buffer;
char *filename = basename(fh);
unsigned int required_size;
loff_t file_size;
/* check buffer size: */
required_size = sizeof(*info) + 2 * (strlen(filename) + 1);
if (*buffer_size < required_size) {
*buffer_size = required_size;
ret = EFI_BUFFER_TOO_SMALL;
goto error;
}
if (set_blk_dev(fh)) {
ret = EFI_DEVICE_ERROR;
goto error;
}
if (fs_size(fh->path, &file_size)) {
ret = EFI_DEVICE_ERROR;
goto error;
}
memset(info, 0, required_size);
info->size = required_size;
info->file_size = file_size;
info->physical_size = file_size;
if (fh->isdir)
info->attribute |= EFI_FILE_DIRECTORY;
ascii2unicode(info->file_name, filename);
} else if (!guidcmp(info_type, &efi_file_system_info_guid)) {
struct efi_file_system_info *info = buffer;
disk_partition_t part;
efi_uintn_t required_size;
int r;
if (fh->fs->part >= 1)
r = part_get_info(fh->fs->desc, fh->fs->part, &part);
else
r = part_get_info_whole_disk(fh->fs->desc, &part);
if (r < 0) {
ret = EFI_DEVICE_ERROR;
goto error;
}
required_size = sizeof(info) + 2 *
(strlen((const char *)part.name) + 1);
if (*buffer_size < required_size) {
*buffer_size = required_size;
ret = EFI_BUFFER_TOO_SMALL;
goto error;
}
memset(info, 0, required_size);
info->size = required_size;
info->read_only = true;
info->volume_size = part.size * part.blksz;
info->free_space = 0;
info->block_size = part.blksz;
/*
* TODO: The volume label is not available in U-Boot.
* Use the partition name as substitute.
*/
ascii2unicode((u16 *)info->volume_label,
(const char *)part.name);
} else {
ret = EFI_UNSUPPORTED;
}
error:
return EFI_EXIT(ret);
}
static efi_status_t EFIAPI efi_file_setinfo(struct efi_file_handle *file,
const efi_guid_t *info_type,
efi_uintn_t buffer_size,
void *buffer)
{
struct file_handle *fh = to_fh(file);
efi_status_t ret = EFI_UNSUPPORTED;
EFI_ENTRY("%p, %pUl, %zu, %p", file, info_type, buffer_size, buffer);
if (!guidcmp(info_type, &efi_file_info_guid)) {
struct efi_file_info *info = (struct efi_file_info *)buffer;
char *filename = basename(fh);
char *new_file_name, *pos;
loff_t file_size;
if (buffer_size < sizeof(struct efi_file_info)) {
ret = EFI_BAD_BUFFER_SIZE;
goto out;
}
/* We cannot change the directory attribute */
if (!fh->isdir != !(info->attribute & EFI_FILE_DIRECTORY)) {
ret = EFI_ACCESS_DENIED;
goto out;
}
/* Check for renaming */
new_file_name = malloc(utf16_utf8_strlen(info->file_name));
if (!new_file_name) {
ret = EFI_OUT_OF_RESOURCES;
goto out;
}
pos = new_file_name;
utf16_utf8_strcpy(&pos, info->file_name);
if (strcmp(new_file_name, filename)) {
/* TODO: we do not support renaming */
EFI_PRINT("Renaming not supported\n");
free(new_file_name);
ret = EFI_ACCESS_DENIED;
goto out;
}
free(new_file_name);
/* Check for truncation */
if (set_blk_dev(fh)) {
ret = EFI_DEVICE_ERROR;
goto out;
}
if (fs_size(fh->path, &file_size)) {
ret = EFI_DEVICE_ERROR;
goto out;
}
if (file_size != info->file_size) {
/* TODO: we do not support truncation */
EFI_PRINT("Truncation not supported\n");
ret = EFI_ACCESS_DENIED;
goto out;
}
/*
* We do not care for the other attributes
* TODO: Support read only
*/
ret = EFI_SUCCESS;
} else if (!guidcmp(info_type, &efi_file_system_info_guid)) {
if (buffer_size < sizeof(struct efi_file_system_info)) {
ret = EFI_BAD_BUFFER_SIZE;
goto out;
}
} else {
ret = EFI_UNSUPPORTED;
}
out:
return EFI_EXIT(ret);
}
static efi_status_t EFIAPI efi_file_flush(struct efi_file_handle *file)
{
EFI_ENTRY("%p", file);
return EFI_EXIT(EFI_SUCCESS);
}
static const struct efi_file_handle efi_file_handle_protocol = {
/*
* TODO: We currently only support EFI file protocol revision 0x00010000
* while UEFI specs 2.4 - 2.7 prescribe revision 0x00020000.
*/
.rev = EFI_FILE_PROTOCOL_REVISION,
.open = efi_file_open,
.close = efi_file_close,
.delete = efi_file_delete,
.read = efi_file_read,
.write = efi_file_write,
.getpos = efi_file_getpos,
.setpos = efi_file_setpos,
.getinfo = efi_file_getinfo,
.setinfo = efi_file_setinfo,
.flush = efi_file_flush,
};
/**
* efi_file_from_path() - open file via device path
*
* @fp: device path
* @return: EFI_FILE_PROTOCOL for the file or NULL
*/
struct efi_file_handle *efi_file_from_path(struct efi_device_path *fp)
{
struct efi_simple_file_system_protocol *v;
struct efi_file_handle *f;
efi_status_t ret;
v = efi_fs_from_path(fp);
if (!v)
return NULL;
EFI_CALL(ret = v->open_volume(v, &f));
if (ret != EFI_SUCCESS)
return NULL;
/* Skip over device-path nodes before the file path. */
while (fp && !EFI_DP_TYPE(fp, MEDIA_DEVICE, FILE_PATH))
fp = efi_dp_next(fp);
/*
* Step through the nodes of the directory path until the actual file
* node is reached which is the final node in the device path.
*/
while (fp) {
struct efi_device_path_file_path *fdp =
container_of(fp, struct efi_device_path_file_path, dp);
struct efi_file_handle *f2;
u16 *filename;
if (!EFI_DP_TYPE(fp, MEDIA_DEVICE, FILE_PATH)) {
printf("bad file path!\n");
f->close(f);
return NULL;
}
filename = u16_strdup(fdp->str);
if (!filename)
return NULL;
EFI_CALL(ret = f->open(f, &f2, filename,
EFI_FILE_MODE_READ, 0));
free(filename);
if (ret != EFI_SUCCESS)
return NULL;
fp = efi_dp_next(fp);
EFI_CALL(f->close(f));
f = f2;
}
return f;
}
static efi_status_t EFIAPI
efi_open_volume(struct efi_simple_file_system_protocol *this,
struct efi_file_handle **root)
{
struct file_system *fs = to_fs(this);
EFI_ENTRY("%p, %p", this, root);
*root = file_open(fs, NULL, NULL, 0, 0);
return EFI_EXIT(EFI_SUCCESS);
}
struct efi_simple_file_system_protocol *
efi_simple_file_system(struct blk_desc *desc, int part,
struct efi_device_path *dp)
{
struct file_system *fs;
fs = calloc(1, sizeof(*fs));
fs->base.rev = EFI_SIMPLE_FILE_SYSTEM_PROTOCOL_REVISION;
fs->base.open_volume = efi_open_volume;
fs->desc = desc;
fs->part = part;
fs->dp = dp;
return &fs->base;
}