source: vendor/current/source3/modules/vfs_acl_tdb.c@ 427

/*
 * Store Windows ACLs in a tdb.
 *
 * Copyright (C) Volker Lendecke, 2008
 * Copyright (C) Jeremy Allison, 2008
 *
 * 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 <http://www.gnu.org/licenses/>.
 */

/* NOTE: This is an experimental module, not yet finished. JRA. */

#include "includes.h"
#include "librpc/gen_ndr/xattr.h"
#include "librpc/gen_ndr/ndr_xattr.h"
#include "../lib/crypto/crypto.h"

#undef DBGC_CLASS
#define DBGC_CLASS DBGC_VFS

#include "modules/vfs_acl_common.c"

static unsigned int ref_count;
static struct db_context *acl_db;

/*******************************************************************
 Open acl_db if not already open, increment ref count.
*******************************************************************/

static bool acl_tdb_init(void)
{
        char *dbname;

        if (acl_db) {
                ref_count++;
                return true;
        }

        dbname = state_path("file_ntacls.tdb");

        if (dbname == NULL) {
                errno = ENOSYS;
                return false;
        }

        become_root();
        acl_db = db_open(NULL, dbname, 0, TDB_DEFAULT, O_RDWR|O_CREAT, 0600);
        unbecome_root();

        if (acl_db == NULL) {
#if defined(ENOTSUP)
                errno = ENOTSUP;
#else
                errno = ENOSYS;
#endif
                TALLOC_FREE(dbname);
                return false;
        }

        ref_count++;
        TALLOC_FREE(dbname);
        return true;
}

/*******************************************************************
 Lower ref count and close acl_db if zero.
*******************************************************************/

static void disconnect_acl_tdb(struct vfs_handle_struct *handle)
{
        SMB_VFS_NEXT_DISCONNECT(handle);
        ref_count--;
        if (ref_count == 0) {
                TALLOC_FREE(acl_db);
        }
}

/*******************************************************************
 Fetch_lock the tdb acl record for a file
*******************************************************************/

static struct db_record *acl_tdb_lock(TALLOC_CTX *mem_ctx,
                                        struct db_context *db,
                                        const struct file_id *id)
{
        uint8 id_buf[16];

        /* For backwards compatibility only store the dev/inode. */
        push_file_id_16((char *)id_buf, id);
        return db->fetch_locked(db,
                                mem_ctx,
                                make_tdb_data(id_buf,
                                        sizeof(id_buf)));
}

/*******************************************************************
 Delete the tdb acl record for a file
*******************************************************************/

static NTSTATUS acl_tdb_delete(vfs_handle_struct *handle,
                                struct db_context *db,
                                SMB_STRUCT_STAT *psbuf)
{
        NTSTATUS status;
        struct file_id id = vfs_file_id_from_sbuf(handle->conn, psbuf);
        struct db_record *rec = acl_tdb_lock(talloc_tos(), db, &id);

        /*
         * If rec == NULL there's not much we can do about it
         */

        if (rec == NULL) {
                DEBUG(10,("acl_tdb_delete: rec == NULL\n"));
                TALLOC_FREE(rec);
                return NT_STATUS_OK;
        }

        status = rec->delete_rec(rec);
        TALLOC_FREE(rec);
        return status;
}

/*******************************************************************
 Pull a security descriptor into a DATA_BLOB from a tdb store.
*******************************************************************/

static NTSTATUS get_acl_blob(TALLOC_CTX *ctx,
                        vfs_handle_struct *handle,
                        files_struct *fsp,
                        const char *name,
                        DATA_BLOB *pblob)
{
        uint8 id_buf[16];
        TDB_DATA data;
        struct file_id id;
        struct db_context *db = acl_db;
        NTSTATUS status = NT_STATUS_OK;
        SMB_STRUCT_STAT sbuf;

        ZERO_STRUCT(sbuf);

        if (fsp) {
                status = vfs_stat_fsp(fsp);
                sbuf = fsp->fsp_name->st;
        } else {
                int ret = vfs_stat_smb_fname(handle->conn, name, &sbuf);
                if (ret == -1) {
                        status = map_nt_error_from_unix(errno);
                }
        }

        if (!NT_STATUS_IS_OK(status)) {
                return status;
        }

        id = vfs_file_id_from_sbuf(handle->conn, &sbuf);

        /* For backwards compatibility only store the dev/inode. */
        push_file_id_16((char *)id_buf, &id);

        if (db->fetch(db,
                        ctx,
                        make_tdb_data(id_buf, sizeof(id_buf)),
                        &data) == -1) {
                return NT_STATUS_INTERNAL_DB_CORRUPTION;
        }

        pblob->data = data.dptr;
        pblob->length = data.dsize;

        DEBUG(10,("get_acl_blob: returned %u bytes from file %s\n",
                (unsigned int)data.dsize, name ));

        if (pblob->length == 0 || pblob->data == NULL) {
                return NT_STATUS_NOT_FOUND;
        }
        return NT_STATUS_OK;
}

/*******************************************************************
 Store a DATA_BLOB into a tdb record given an fsp pointer.
*******************************************************************/

static NTSTATUS store_acl_blob_fsp(vfs_handle_struct *handle,
                                files_struct *fsp,
                                DATA_BLOB *pblob)
{
        uint8 id_buf[16];
        struct file_id id;
        TDB_DATA data;
        struct db_context *db = acl_db;
        struct db_record *rec;
        NTSTATUS status;

        DEBUG(10,("store_acl_blob_fsp: storing blob length %u on file %s\n",
                  (unsigned int)pblob->length, fsp_str_dbg(fsp)));

        status = vfs_stat_fsp(fsp);
        if (!NT_STATUS_IS_OK(status)) {
                return status;
        }

        id = vfs_file_id_from_sbuf(handle->conn, &fsp->fsp_name->st);

        /* For backwards compatibility only store the dev/inode. */
        push_file_id_16((char *)id_buf, &id);
        rec = db->fetch_locked(db, talloc_tos(),
                                make_tdb_data(id_buf,
                                        sizeof(id_buf)));
        if (rec == NULL) {
                DEBUG(0, ("store_acl_blob_fsp_tdb: fetch_lock failed\n"));
                return NT_STATUS_INTERNAL_DB_CORRUPTION;
        }
        data.dptr = pblob->data;
        data.dsize = pblob->length;
        return rec->store(rec, data, 0);
}

/*********************************************************************
 On unlink we need to delete the tdb record (if using tdb).
*********************************************************************/

static int unlink_acl_tdb(vfs_handle_struct *handle,
                          const struct smb_filename *smb_fname)
{
        struct smb_filename *smb_fname_tmp = NULL;
        struct db_context *db = acl_db;
        NTSTATUS status;
        int ret = -1;

        status = copy_smb_filename(talloc_tos(), smb_fname, &smb_fname_tmp);
        if (!NT_STATUS_IS_OK(status)) {
                errno = map_errno_from_nt_status(status);
                goto out;
        }

        if (lp_posix_pathnames()) {
                ret = SMB_VFS_LSTAT(handle->conn, smb_fname_tmp);
        } else {
                ret = SMB_VFS_STAT(handle->conn, smb_fname_tmp);
        }

        if (ret == -1) {
                goto out;
        }

        ret = unlink_acl_common(handle, smb_fname_tmp);

        if (ret == -1) {
                goto out;
        }

        acl_tdb_delete(handle, db, &smb_fname_tmp->st);
 out:
        return ret;
}

/*********************************************************************
 On rmdir we need to delete the tdb record (if using tdb).
*********************************************************************/

static int rmdir_acl_tdb(vfs_handle_struct *handle, const char *path)
{

        SMB_STRUCT_STAT sbuf;
        struct db_context *db = acl_db;
        int ret = -1;

        if (lp_posix_pathnames()) {
                ret = vfs_lstat_smb_fname(handle->conn, path, &sbuf);
        } else {
                ret = vfs_stat_smb_fname(handle->conn, path, &sbuf);
        }

        if (ret == -1) {
                return -1;
        }

        ret = rmdir_acl_common(handle, path);
        if (ret == -1) {
                return -1;
        }

        acl_tdb_delete(handle, db, &sbuf);
        return 0;
}

/*******************************************************************
 Handle opening the storage tdb if so configured.
*******************************************************************/

static int connect_acl_tdb(struct vfs_handle_struct *handle,
                                const char *service,
                                const char *user)
{
        int ret = SMB_VFS_NEXT_CONNECT(handle, service, user);

        if (ret < 0) {
                return ret;
        }

        if (!acl_tdb_init()) {
                SMB_VFS_NEXT_DISCONNECT(handle);
                return -1;
        }

        /* Ensure we have "inherit acls = yes" if we're
         * using this module. */
        DEBUG(2,("connect_acl_tdb: setting 'inherit acls = true' "
                "and 'dos filemode = true' for service %s\n",
                service ));
        lp_do_parameter(SNUM(handle->conn), "inherit acls", "true");
        lp_do_parameter(SNUM(handle->conn), "dos filemode", "true");

        return 0;
}

/*********************************************************************
 Remove a Windows ACL - we're setting the underlying POSIX ACL.
*********************************************************************/

static int sys_acl_set_file_tdb(vfs_handle_struct *handle,
                              const char *path,
                              SMB_ACL_TYPE_T type,
                              SMB_ACL_T theacl)
{
        SMB_STRUCT_STAT sbuf;
        struct db_context *db = acl_db;
        int ret = -1;

        if (lp_posix_pathnames()) {
                ret = vfs_lstat_smb_fname(handle->conn, path, &sbuf);
        } else {
                ret = vfs_stat_smb_fname(handle->conn, path, &sbuf);
        }

        if (ret == -1) {
                return -1;
        }

        ret = SMB_VFS_NEXT_SYS_ACL_SET_FILE(handle,
                                                path,
                                                type,
                                                theacl);
        if (ret == -1) {
                return -1;
        }

        acl_tdb_delete(handle, db, &sbuf);
        return 0;
}

/*********************************************************************
 Remove a Windows ACL - we're setting the underlying POSIX ACL.
*********************************************************************/

static int sys_acl_set_fd_tdb(vfs_handle_struct *handle,
                            files_struct *fsp,
                            SMB_ACL_T theacl)
{
        struct db_context *db = acl_db;
        NTSTATUS status;
        int ret;

        status = vfs_stat_fsp(fsp);
        if (!NT_STATUS_IS_OK(status)) {
                return -1;
        }

        ret = SMB_VFS_NEXT_SYS_ACL_SET_FD(handle,
                                                fsp,
                                                theacl);
        if (ret == -1) {
                return -1;
        }

        acl_tdb_delete(handle, db, &fsp->fsp_name->st);
        return 0;
}

static struct vfs_fn_pointers vfs_acl_tdb_fns = {
        .connect_fn = connect_acl_tdb,
        .disconnect = disconnect_acl_tdb,
        .opendir = opendir_acl_common,
        .mkdir = mkdir_acl_common,
        .open = open_acl_common,
        .create_file = create_file_acl_common,
        .unlink = unlink_acl_tdb,
        .rmdir = rmdir_acl_tdb,
        .fget_nt_acl = fget_nt_acl_common,
        .get_nt_acl = get_nt_acl_common,
        .fset_nt_acl = fset_nt_acl_common,
        .sys_acl_set_file = sys_acl_set_file_tdb,
        .sys_acl_set_fd = sys_acl_set_fd_tdb
};

NTSTATUS vfs_acl_tdb_init(void)
{
        return smb_register_vfs(SMB_VFS_INTERFACE_VERSION, "acl_tdb",
                                &vfs_acl_tdb_fns);
}