/*
Unix SMB/Netbios implementation.
Version 1.9.
VFS initialisation and support functions
Copyright (C) Tim Potter 1999
Copyright (C) Alexander Bokovoy 2002
Copyright (C) James Peach 2006
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see .
This work was sponsored by Optifacio Software Services, Inc.
*/
#include "includes.h"
#include "smbd/globals.h"
#undef DBGC_CLASS
#define DBGC_CLASS DBGC_VFS
static_decl_vfs;
struct vfs_init_function_entry {
char *name;
const vfs_op_tuple *vfs_op_tuples;
struct vfs_init_function_entry *prev, *next;
};
/****************************************************************************
maintain the list of available backends
****************************************************************************/
static struct vfs_init_function_entry *vfs_find_backend_entry(const char *name)
{
struct vfs_init_function_entry *entry = backends;
DEBUG(10, ("vfs_find_backend_entry called for %s\n", name));
while(entry) {
if (strcmp(entry->name, name)==0) return entry;
entry = entry->next;
}
return NULL;
}
NTSTATUS smb_register_vfs(int version, const char *name, const vfs_op_tuple *vfs_op_tuples)
{
struct vfs_init_function_entry *entry = backends;
if ((version != SMB_VFS_INTERFACE_VERSION)) {
DEBUG(0, ("Failed to register vfs module.\n"
"The module was compiled against SMB_VFS_INTERFACE_VERSION %d,\n"
"current SMB_VFS_INTERFACE_VERSION is %d.\n"
"Please recompile against the current Samba Version!\n",
version, SMB_VFS_INTERFACE_VERSION));
return NT_STATUS_OBJECT_TYPE_MISMATCH;
}
if (!name || !name[0] || !vfs_op_tuples) {
DEBUG(0,("smb_register_vfs() called with NULL pointer or empty name!\n"));
return NT_STATUS_INVALID_PARAMETER;
}
if (vfs_find_backend_entry(name)) {
DEBUG(0,("VFS module %s already loaded!\n", name));
return NT_STATUS_OBJECT_NAME_COLLISION;
}
entry = SMB_XMALLOC_P(struct vfs_init_function_entry);
entry->name = smb_xstrdup(name);
entry->vfs_op_tuples = vfs_op_tuples;
DLIST_ADD(backends, entry);
DEBUG(5, ("Successfully added vfs backend '%s'\n", name));
return NT_STATUS_OK;
}
/****************************************************************************
initialise default vfs hooks
****************************************************************************/
static void vfs_init_default(connection_struct *conn)
{
DEBUG(3, ("Initialising default vfs hooks\n"));
vfs_init_custom(conn, DEFAULT_VFS_MODULE_NAME);
}
/****************************************************************************
initialise custom vfs hooks
****************************************************************************/
static inline void vfs_set_operation(struct vfs_ops * vfs, vfs_op_type which,
struct vfs_handle_struct * handle, void * op)
{
((struct vfs_handle_struct **)&vfs->handles)[which] = handle;
((void **)(void *)&vfs->ops)[which] = op;
}
bool vfs_init_custom(connection_struct *conn, const char *vfs_object)
{
const vfs_op_tuple *ops;
char *module_path = NULL;
char *module_name = NULL;
char *module_param = NULL, *p;
int i;
vfs_handle_struct *handle;
const struct vfs_init_function_entry *entry;
if (!conn||!vfs_object||!vfs_object[0]) {
DEBUG(0,("vfs_init_custon() called with NULL pointer or emtpy vfs_object!\n"));
return False;
}
if(!backends) {
static_init_vfs;
}
DEBUG(3, ("Initialising custom vfs hooks from [%s]\n", vfs_object));
module_path = smb_xstrdup(vfs_object);
p = strchr_m(module_path, ':');
if (p) {
*p = 0;
module_param = p+1;
trim_char(module_param, ' ', ' ');
}
trim_char(module_path, ' ', ' ');
module_name = smb_xstrdup(module_path);
if ((module_name[0] == '/') &&
(strcmp(module_path, DEFAULT_VFS_MODULE_NAME) != 0)) {
/*
* Extract the module name from the path. Just use the base
* name of the last path component.
*/
SAFE_FREE(module_name);
module_name = smb_xstrdup(strrchr_m(module_path, '/')+1);
p = strchr_m(module_name, '.');
if (p != NULL) {
*p = '\0';
}
}
/* First, try to load the module with the new module system */
entry = vfs_find_backend_entry(module_name);
if (!entry) {
NTSTATUS status;
DEBUG(5, ("vfs module [%s] not loaded - trying to load...\n",
vfs_object));
status = smb_probe_module("vfs", module_path);
if (!NT_STATUS_IS_OK(status)) {
DEBUG(0, ("error probing vfs module '%s': %s\n",
module_path, nt_errstr(status)));
goto fail;
}
entry = vfs_find_backend_entry(module_name);
if (!entry) {
DEBUG(0,("Can't find a vfs module [%s]\n",vfs_object));
goto fail;
}
}
DEBUGADD(5,("Successfully loaded vfs module [%s] with the new modules system\n", vfs_object));
if ((ops = entry->vfs_op_tuples) == NULL) {
DEBUG(0, ("entry->vfs_op_tuples==NULL for [%s] failed\n", vfs_object));
goto fail;
}
handle = TALLOC_ZERO_P(conn, vfs_handle_struct);
if (!handle) {
DEBUG(0,("TALLOC_ZERO() failed!\n"));
goto fail;
}
memcpy(&handle->vfs_next, &conn->vfs, sizeof(struct vfs_ops));
handle->conn = conn;
if (module_param) {
handle->param = talloc_strdup(conn, module_param);
}
DLIST_ADD(conn->vfs_handles, handle);
for(i=0; ops[i].op != NULL; i++) {
DEBUG(5, ("Checking operation #%d (type %d, layer %d)\n", i, ops[i].type, ops[i].layer));
if(ops[i].layer == SMB_VFS_LAYER_OPAQUE) {
/* If this operation was already made opaque by different module, it
* will be overridden here.
*/
DEBUGADD(5, ("Making operation type %d opaque [module %s]\n", ops[i].type, vfs_object));
vfs_set_operation(&conn->vfs_opaque, ops[i].type, handle, ops[i].op);
}
/* Change current VFS disposition*/
DEBUGADD(5, ("Accepting operation type %d from module %s\n", ops[i].type, vfs_object));
vfs_set_operation(&conn->vfs, ops[i].type, handle, ops[i].op);
}
SAFE_FREE(module_path);
SAFE_FREE(module_name);
return True;
fail:
SAFE_FREE(module_path);
SAFE_FREE(module_name);
return False;
}
/*****************************************************************
Allow VFS modules to extend files_struct with VFS-specific state.
This will be ok for small numbers of extensions, but might need to
be refactored if it becomes more widely used.
******************************************************************/
#define EXT_DATA_AREA(e) ((uint8 *)(e) + sizeof(struct vfs_fsp_data))
void *vfs_add_fsp_extension_notype(vfs_handle_struct *handle,
files_struct *fsp, size_t ext_size,
void (*destroy_fn)(void *p_data))
{
struct vfs_fsp_data *ext;
void * ext_data;
/* Prevent VFS modules adding multiple extensions. */
if ((ext_data = vfs_fetch_fsp_extension(handle, fsp))) {
return ext_data;
}
ext = (struct vfs_fsp_data *)TALLOC_ZERO(
handle->conn, sizeof(struct vfs_fsp_data) + ext_size);
if (ext == NULL) {
return NULL;
}
ext->owner = handle;
ext->next = fsp->vfs_extension;
ext->destroy = destroy_fn;
fsp->vfs_extension = ext;
return EXT_DATA_AREA(ext);
}
void vfs_remove_fsp_extension(vfs_handle_struct *handle, files_struct *fsp)
{
struct vfs_fsp_data *curr;
struct vfs_fsp_data *prev;
for (curr = fsp->vfs_extension, prev = NULL;
curr;
prev = curr, curr = curr->next) {
if (curr->owner == handle) {
if (prev) {
prev->next = curr->next;
} else {
fsp->vfs_extension = curr->next;
}
if (curr->destroy) {
curr->destroy(EXT_DATA_AREA(curr));
}
TALLOC_FREE(curr);
return;
}
}
}
void *vfs_memctx_fsp_extension(vfs_handle_struct *handle, files_struct *fsp)
{
struct vfs_fsp_data *head;
for (head = fsp->vfs_extension; head; head = head->next) {
if (head->owner == handle) {
return head;
}
}
return NULL;
}
void *vfs_fetch_fsp_extension(vfs_handle_struct *handle, files_struct *fsp)
{
struct vfs_fsp_data *head;
head = (struct vfs_fsp_data *)vfs_memctx_fsp_extension(handle, fsp);
if (head != NULL) {
return EXT_DATA_AREA(head);
}
return NULL;
}
#undef EXT_DATA_AREA
/*****************************************************************
Generic VFS init.
******************************************************************/
bool smbd_vfs_init(connection_struct *conn)
{
const char **vfs_objects;
unsigned int i = 0;
int j = 0;
/* Normal share - initialise with disk access functions */
vfs_init_default(conn);
vfs_objects = lp_vfs_objects(SNUM(conn));
/* Override VFS functions if 'vfs object' was not specified*/
if (!vfs_objects || !vfs_objects[0])
return True;
for (i=0; vfs_objects[i] ;) {
i++;
}
for (j=i-1; j >= 0; j--) {
if (!vfs_init_custom(conn, vfs_objects[j])) {
DEBUG(0, ("smbd_vfs_init: vfs_init_custom failed for %s\n", vfs_objects[j]));
return False;
}
}
return True;
}
/*******************************************************************
Check if directory exists.
********************************************************************/
bool vfs_directory_exist(connection_struct *conn, const char *dname, SMB_STRUCT_STAT *st)
{
SMB_STRUCT_STAT st2;
bool ret;
if (!st)
st = &st2;
if (SMB_VFS_STAT(conn,dname,st) != 0)
return(False);
ret = S_ISDIR(st->st_ex_mode);
if(!ret)
errno = ENOTDIR;
return ret;
}
/*******************************************************************
Check if an object exists in the vfs.
********************************************************************/
bool vfs_object_exist(connection_struct *conn,const char *fname,SMB_STRUCT_STAT *sbuf)
{
SMB_STRUCT_STAT st;
if (!sbuf)
sbuf = &st;
ZERO_STRUCTP(sbuf);
if (SMB_VFS_STAT(conn,fname,sbuf) == -1)
return(False);
return True;
}
/*******************************************************************
Check if a file exists in the vfs.
********************************************************************/
bool vfs_file_exist(connection_struct *conn, const char *fname,SMB_STRUCT_STAT *sbuf)
{
SMB_STRUCT_STAT st;
if (!sbuf)
sbuf = &st;
ZERO_STRUCTP(sbuf);
if (SMB_VFS_STAT(conn,fname,sbuf) == -1)
return False;
return(S_ISREG(sbuf->st_ex_mode));
}
/****************************************************************************
Read data from fsp on the vfs. (note: EINTR re-read differs from vfs_write_data)
****************************************************************************/
ssize_t vfs_read_data(files_struct *fsp, char *buf, size_t byte_count)
{
size_t total=0;
while (total < byte_count)
{
ssize_t ret = SMB_VFS_READ(fsp, buf + total,
byte_count - total);
if (ret == 0) return total;
if (ret == -1) {
if (errno == EINTR)
continue;
else
return -1;
}
total += ret;
}
return (ssize_t)total;
}
ssize_t vfs_pread_data(files_struct *fsp, char *buf,
size_t byte_count, SMB_OFF_T offset)
{
size_t total=0;
while (total < byte_count)
{
ssize_t ret = SMB_VFS_PREAD(fsp, buf + total,
byte_count - total, offset + total);
if (ret == 0) return total;
if (ret == -1) {
if (errno == EINTR)
continue;
else
return -1;
}
total += ret;
}
return (ssize_t)total;
}
/****************************************************************************
Write data to a fd on the vfs.
****************************************************************************/
ssize_t vfs_write_data(struct smb_request *req,
files_struct *fsp,
const char *buffer,
size_t N)
{
size_t total=0;
ssize_t ret;
if (req && req->unread_bytes) {
SMB_ASSERT(req->unread_bytes == N);
/* VFS_RECVFILE must drain the socket
* before returning. */
req->unread_bytes = 0;
return SMB_VFS_RECVFILE(smbd_server_fd(),
fsp,
(SMB_OFF_T)-1,
N);
}
while (total < N) {
ret = SMB_VFS_WRITE(fsp, buffer + total, N - total);
if (ret == -1)
return -1;
if (ret == 0)
return total;
total += ret;
}
return (ssize_t)total;
}
ssize_t vfs_pwrite_data(struct smb_request *req,
files_struct *fsp,
const char *buffer,
size_t N,
SMB_OFF_T offset)
{
size_t total=0;
ssize_t ret;
if (req && req->unread_bytes) {
SMB_ASSERT(req->unread_bytes == N);
/* VFS_RECVFILE must drain the socket
* before returning. */
req->unread_bytes = 0;
return SMB_VFS_RECVFILE(smbd_server_fd(),
fsp,
offset,
N);
}
while (total < N) {
ret = SMB_VFS_PWRITE(fsp, buffer + total, N - total,
offset + total);
if (ret == -1)
return -1;
if (ret == 0)
return total;
total += ret;
}
return (ssize_t)total;
}
/****************************************************************************
An allocate file space call using the vfs interface.
Allocates space for a file from a filedescriptor.
Returns 0 on success, -1 on failure.
****************************************************************************/
int vfs_allocate_file_space(files_struct *fsp, uint64_t len)
{
int ret;
SMB_STRUCT_STAT st;
connection_struct *conn = fsp->conn;
uint64_t space_avail;
uint64_t bsize,dfree,dsize;
/*
* Actually try and commit the space on disk....
*/
DEBUG(10,("vfs_allocate_file_space: file %s, len %.0f\n", fsp->fsp_name, (double)len ));
if (((SMB_OFF_T)len) < 0) {
DEBUG(0,("vfs_allocate_file_space: %s negative len requested.\n", fsp->fsp_name ));
errno = EINVAL;
return -1;
}
ret = SMB_VFS_FSTAT(fsp, &st);
if (ret == -1)
return ret;
if (len == (uint64_t)st.st_ex_size)
return 0;
if (len < (uint64_t)st.st_ex_size) {
/* Shrink - use ftruncate. */
DEBUG(10,("vfs_allocate_file_space: file %s, shrink. Current size %.0f\n",
fsp->fsp_name, (double)st.st_ex_size ));
contend_level2_oplocks_begin(fsp, LEVEL2_CONTEND_ALLOC_SHRINK);
flush_write_cache(fsp, SIZECHANGE_FLUSH);
if ((ret = SMB_VFS_FTRUNCATE(fsp, (SMB_OFF_T)len)) != -1) {
set_filelen_write_cache(fsp, len);
}
contend_level2_oplocks_end(fsp, LEVEL2_CONTEND_ALLOC_SHRINK);
return ret;
}
/* Grow - we need to test if we have enough space. */
contend_level2_oplocks_begin(fsp, LEVEL2_CONTEND_ALLOC_GROW);
contend_level2_oplocks_end(fsp, LEVEL2_CONTEND_ALLOC_GROW);
if (!lp_strict_allocate(SNUM(fsp->conn)))
return 0;
len -= st.st_ex_size;
len /= 1024; /* Len is now number of 1k blocks needed. */
space_avail = get_dfree_info(conn,fsp->fsp_name,False,&bsize,&dfree,&dsize);
if (space_avail == (uint64_t)-1) {
return -1;
}
DEBUG(10,("vfs_allocate_file_space: file %s, grow. Current size %.0f, needed blocks = %.0f, space avail = %.0f\n",
fsp->fsp_name, (double)st.st_ex_size, (double)len, (double)space_avail ));
if (len > space_avail) {
errno = ENOSPC;
return -1;
}
return 0;
}
/****************************************************************************
A vfs set_filelen call.
set the length of a file from a filedescriptor.
Returns 0 on success, -1 on failure.
****************************************************************************/
int vfs_set_filelen(files_struct *fsp, SMB_OFF_T len)
{
int ret;
contend_level2_oplocks_begin(fsp, LEVEL2_CONTEND_SET_FILE_LEN);
DEBUG(10,("vfs_set_filelen: ftruncate %s to len %.0f\n", fsp->fsp_name, (double)len));
flush_write_cache(fsp, SIZECHANGE_FLUSH);
if ((ret = SMB_VFS_FTRUNCATE(fsp, len)) != -1) {
set_filelen_write_cache(fsp, len);
notify_fname(fsp->conn, NOTIFY_ACTION_MODIFIED,
FILE_NOTIFY_CHANGE_SIZE
| FILE_NOTIFY_CHANGE_ATTRIBUTES,
fsp->fsp_name);
}
contend_level2_oplocks_end(fsp, LEVEL2_CONTEND_SET_FILE_LEN);
return ret;
}
/****************************************************************************
A vfs fill sparse call.
Writes zeros from the end of file to len, if len is greater than EOF.
Used only by strict_sync.
Returns 0 on success, -1 on failure.
****************************************************************************/
#define SPARSE_BUF_WRITE_SIZE (32*1024)
int vfs_fill_sparse(files_struct *fsp, SMB_OFF_T len)
{
int ret;
SMB_STRUCT_STAT st;
SMB_OFF_T offset;
size_t total;
size_t num_to_write;
ssize_t pwrite_ret;
ret = SMB_VFS_FSTAT(fsp, &st);
if (ret == -1) {
return ret;
}
if (len <= st.st_ex_size) {
return 0;
}
DEBUG(10,("vfs_fill_sparse: write zeros in file %s from len %.0f to len %.0f (%.0f bytes)\n",
fsp->fsp_name, (double)st.st_ex_size, (double)len, (double)(len - st.st_ex_size)));
contend_level2_oplocks_begin(fsp, LEVEL2_CONTEND_FILL_SPARSE);
flush_write_cache(fsp, SIZECHANGE_FLUSH);
if (!sparse_buf) {
sparse_buf = SMB_CALLOC_ARRAY(char, SPARSE_BUF_WRITE_SIZE);
if (!sparse_buf) {
errno = ENOMEM;
ret = -1;
goto out;
}
}
offset = st.st_ex_size;
num_to_write = len - st.st_ex_size;
total = 0;
while (total < num_to_write) {
size_t curr_write_size = MIN(SPARSE_BUF_WRITE_SIZE, (num_to_write - total));
pwrite_ret = SMB_VFS_PWRITE(fsp, sparse_buf, curr_write_size, offset + total);
if (pwrite_ret == -1) {
DEBUG(10,("vfs_fill_sparse: SMB_VFS_PWRITE for file %s failed with error %s\n",
fsp->fsp_name, strerror(errno) ));
ret = -1;
goto out;
}
if (pwrite_ret == 0) {
ret = 0;
goto out;
}
total += pwrite_ret;
}
set_filelen_write_cache(fsp, len);
ret = 0;
out:
contend_level2_oplocks_end(fsp, LEVEL2_CONTEND_FILL_SPARSE);
return ret;
}
/****************************************************************************
Transfer some data (n bytes) between two file_struct's.
****************************************************************************/
static ssize_t vfs_read_fn(void *file, void *buf, size_t len)
{
struct files_struct *fsp = (struct files_struct *)file;
return SMB_VFS_READ(fsp, buf, len);
}
static ssize_t vfs_write_fn(void *file, const void *buf, size_t len)
{
struct files_struct *fsp = (struct files_struct *)file;
return SMB_VFS_WRITE(fsp, buf, len);
}
SMB_OFF_T vfs_transfer_file(files_struct *in, files_struct *out, SMB_OFF_T n)
{
return transfer_file_internal((void *)in, (void *)out, n,
vfs_read_fn, vfs_write_fn);
}
/*******************************************************************
A vfs_readdir wrapper which just returns the file name.
********************************************************************/
char *vfs_readdirname(connection_struct *conn, void *p, SMB_STRUCT_STAT *sbuf)
{
SMB_STRUCT_DIRENT *ptr= NULL;
char *dname;
if (!p)
return(NULL);
ptr = SMB_VFS_READDIR(conn, (DIR *)p, sbuf);
if (!ptr)
return(NULL);
dname = ptr->d_name;
#ifdef NEXT2
if (telldir(p) < 0)
return(NULL);
#endif
#ifdef HAVE_BROKEN_READDIR_NAME
/* using /usr/ucb/cc is BAD */
dname = dname - 2;
#endif
return(dname);
}
/*******************************************************************
A wrapper for vfs_chdir().
********************************************************************/
int vfs_ChDir(connection_struct *conn, const char *path)
{
int res;
if (!LastDir) {
LastDir = SMB_STRDUP("");
}
if (strcsequal(path,"."))
return(0);
if (*path == '/' && strcsequal(LastDir,path))
return(0);
DEBUG(4,("vfs_ChDir to %s\n",path));
res = SMB_VFS_CHDIR(conn,path);
if (!res) {
SAFE_FREE(LastDir);
LastDir = SMB_STRDUP(path);
}
return(res);
}
/*******************************************************************
Return the absolute current directory path - given a UNIX pathname.
Note that this path is returned in DOS format, not UNIX
format. Note this can be called with conn == NULL.
********************************************************************/
char *vfs_GetWd(TALLOC_CTX *ctx, connection_struct *conn)
{
char s[PATH_MAX+1];
SMB_STRUCT_STAT st, st2;
char *result;
DATA_BLOB cache_value;
struct file_id key;
*s = 0;
if (!lp_getwd_cache()) {
goto nocache;
}
SET_STAT_INVALID(st);
if (SMB_VFS_STAT(conn, ".",&st) == -1) {
/*
* Known to fail for root: the directory may be NFS-mounted
* and exported with root_squash (so has no root access).
*/
DEBUG(1,("vfs_GetWd: couldn't stat \".\" error %s "
"(NFS problem ?)\n", strerror(errno) ));
goto nocache;
}
key = vfs_file_id_from_sbuf(conn, &st);
if (!memcache_lookup(smbd_memcache(), GETWD_CACHE,
data_blob_const(&key, sizeof(key)),
&cache_value)) {
goto nocache;
}
SMB_ASSERT((cache_value.length > 0)
&& (cache_value.data[cache_value.length-1] == '\0'));
if ((SMB_VFS_STAT(conn, (char *)cache_value.data, &st2) == 0)
&& (st.st_ex_dev == st2.st_ex_dev) && (st.st_ex_ino == st2.st_ex_ino)
&& (S_ISDIR(st.st_ex_mode))) {
/*
* Ok, we're done
*/
result = talloc_strdup(ctx, (char *)cache_value.data);
if (result == NULL) {
errno = ENOMEM;
}
return result;
}
nocache:
/*
* We don't have the information to hand so rely on traditional
* methods. The very slow getcwd, which spawns a process on some
* systems, or the not quite so bad getwd.
*/
if (!SMB_VFS_GETWD(conn,s)) {
DEBUG(0, ("vfs_GetWd: SMB_VFS_GETWD call failed: %s\n",
strerror(errno)));
return NULL;
}
if (lp_getwd_cache() && VALID_STAT(st)) {
key = vfs_file_id_from_sbuf(conn, &st);
memcache_add(smbd_memcache(), GETWD_CACHE,
data_blob_const(&key, sizeof(key)),
data_blob_const(s, strlen(s)+1));
}
result = talloc_strdup(ctx, s);
if (result == NULL) {
errno = ENOMEM;
}
return result;
}
/*******************************************************************
Reduce a file name, removing .. elements and checking that
it is below dir in the heirachy. This uses realpath.
********************************************************************/
NTSTATUS check_reduced_name(connection_struct *conn, const char *fname)
{
#ifdef REALPATH_TAKES_NULL
bool free_resolved_name = True;
#else
char resolved_name_buf[PATH_MAX+1];
bool free_resolved_name = False;
#endif
char *resolved_name = NULL;
char *p = NULL;
DEBUG(3,("reduce_name [%s] [%s]\n", fname, conn->connectpath));
#ifdef REALPATH_TAKES_NULL
resolved_name = SMB_VFS_REALPATH(conn,fname,NULL);
#else
resolved_name = SMB_VFS_REALPATH(conn,fname,resolved_name_buf);
#endif
if (!resolved_name) {
switch (errno) {
case ENOTDIR:
DEBUG(3,("reduce_name: Component not a directory in getting realpath for %s\n", fname));
return map_nt_error_from_unix(errno);
case ENOENT:
{
TALLOC_CTX *ctx = talloc_tos();
char *tmp_fname = NULL;
char *last_component = NULL;
/* Last component didn't exist. Remove it and try and canonicalise the directory. */
tmp_fname = talloc_strdup(ctx, fname);
if (!tmp_fname) {
return NT_STATUS_NO_MEMORY;
}
p = strrchr_m(tmp_fname, '/');
if (p) {
*p++ = '\0';
last_component = p;
} else {
last_component = tmp_fname;
tmp_fname = talloc_strdup(ctx,
".");
if (!tmp_fname) {
return NT_STATUS_NO_MEMORY;
}
}
#ifdef REALPATH_TAKES_NULL
resolved_name = SMB_VFS_REALPATH(conn,tmp_fname,NULL);
#else
resolved_name = SMB_VFS_REALPATH(conn,tmp_fname,resolved_name_buf);
#endif
if (!resolved_name) {
DEBUG(3,("reduce_name: couldn't get realpath for %s\n", fname));
return map_nt_error_from_unix(errno);
}
tmp_fname = talloc_asprintf(ctx,
"%s/%s",
resolved_name,
last_component);
if (!tmp_fname) {
return NT_STATUS_NO_MEMORY;
}
#ifdef REALPATH_TAKES_NULL
SAFE_FREE(resolved_name);
resolved_name = SMB_STRDUP(tmp_fname);
if (!resolved_name) {
DEBUG(0,("reduce_name: malloc fail for %s\n", tmp_fname));
return NT_STATUS_NO_MEMORY;
}
#else
safe_strcpy(resolved_name_buf, tmp_fname, PATH_MAX);
resolved_name = resolved_name_buf;
#endif
break;
}
default:
DEBUG(1,("reduce_name: couldn't get realpath for %s\n", fname));
return map_nt_error_from_unix(errno);
}
}
DEBUG(10,("reduce_name realpath [%s] -> [%s]\n", fname, resolved_name));
if (*resolved_name != '/') {
DEBUG(0,("reduce_name: realpath doesn't return absolute paths !\n"));
if (free_resolved_name) {
SAFE_FREE(resolved_name);
}
return NT_STATUS_OBJECT_NAME_INVALID;
}
/* Check for widelinks allowed. */
if (!lp_widelinks(SNUM(conn))
&& (strncmp(conn->connectpath, resolved_name,
strlen(conn->connectpath)) != 0)) {
DEBUG(2, ("reduce_name: Bad access attempt: %s is a symlink outside the share path", fname));
if (free_resolved_name) {
SAFE_FREE(resolved_name);
}
return NT_STATUS_ACCESS_DENIED;
}
/* Check if we are allowing users to follow symlinks */
/* Patch from David Clerc
University of Geneva */
#ifdef S_ISLNK
if (!lp_symlinks(SNUM(conn))) {
SMB_STRUCT_STAT statbuf;
if ( (SMB_VFS_LSTAT(conn,fname,&statbuf) != -1) &&
(S_ISLNK(statbuf.st_ex_mode)) ) {
if (free_resolved_name) {
SAFE_FREE(resolved_name);
}
DEBUG(3,("reduce_name: denied: file path name %s is a symlink\n",resolved_name));
return NT_STATUS_ACCESS_DENIED;
}
}
#endif
DEBUG(3,("reduce_name: %s reduced to %s\n", fname, resolved_name));
if (free_resolved_name) {
SAFE_FREE(resolved_name);
}
return NT_STATUS_OK;
}