davfs2/src/kernel_interface.c

269 lines
7.3 KiB
C

/* kernel_interface.c: interface to fuse and coda kernel mocule.
Copyright (C) 2006, 2007, 2008, 2009 Werner Baumann
This file is part of davfs2.
davfs2 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.
davfs2 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 davfs2; if not, write to the Free Software Foundation,
Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */
#include "config.h"
#include <error.h>
#ifdef HAVE_FCNTL_H
#include <fcntl.h>
#endif
#ifdef HAVE_LIBINTL_H
#include <libintl.h>
#endif
#ifdef HAVE_STDDEF_H
#include <stddef.h>
#endif
#ifdef HAVE_STDINT_H
#include <stdint.h>
#endif
#include <stdio.h>
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#include <string.h>
#ifdef HAVE_SYSLOG_H
#include <syslog.h>
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_SYS_MOUNT_H
#include <sys/mount.h>
#endif
#ifdef HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif
#include "defaults.h"
#include "mount_davfs.h"
#include "cache.h"
#include "coda.h"
#include "fuse_kernel.h"
#include "kernel_interface.h"
#ifdef ENABLE_NLS
#define _(String) gettext(String)
#else
#define _(String) String
#endif
/* Private constants */
/*===================*/
/* Name, major number and minor number of the devices to communicate with the
kernel file system. */
#define FUSE_DEV_NAME "fuse"
#define CODA_DEV_NAME "cfs"
#define CODA_MAJOR 67
#define MAX_CODADEVS 5 /* Coda minor number may be from 0 to 4. */
/* Private function prototypes */
/*=============================*/
static int
init_coda(int *dev, dav_run_msgloop_fn *msg_loop, void **mdata);
static int
init_fuse(int *dev, dav_run_msgloop_fn *msg_loop, void **mdata,
size_t *buf_size, const char *url, const char *mpoint,
unsigned long int mopts, uid_t owner, gid_t group, mode_t mode);
/* Public functions */
/*==================*/
int
dav_init_kernel_interface(int *dev, dav_run_msgloop_fn *msg_loop, void **mdata,
char **kernel_fs, size_t *buf_size, const char *url,
const char *mpoint, const dav_args *args)
{
uid_t orig = geteuid();
seteuid(0);
if (!*kernel_fs)
*kernel_fs = strdup("fuse");
if (!*kernel_fs) abort();
int mounted = 0;
if (strcmp(*kernel_fs, "coda") == 0) {
if (init_coda(dev, msg_loop, mdata) != 0) {
error(0, 0, _("trying fuse kernel file system"));
if (init_fuse(dev, msg_loop, mdata, buf_size, url, mpoint,
args->mopts, args->uid, args->gid, args->dir_mode)
== 0) {
free(*kernel_fs);
*kernel_fs = strdup("fuse");
if (!*kernel_fs) abort();
mounted = 1;
error(0, 0, _("fuse device opened successfully"));
} else {
exit(EXIT_FAILURE);
}
}
} else if (strcmp(*kernel_fs, "fuse") == 0) {
if (init_fuse(dev, msg_loop, mdata, buf_size, url, mpoint, args->mopts,
args->uid, args->gid, args->dir_mode) == 0) {
mounted = 1;
} else {
error(0, 0, _("trying coda kernel file system"));
if (init_coda(dev, msg_loop, mdata) == 0) {
free(*kernel_fs);
*kernel_fs = strdup("coda");
if (*kernel_fs == NULL)
abort();
error(0, 0, _("coda device opened successfully"));
} else {
exit(EXIT_FAILURE);
}
}
} else {
error(EXIT_FAILURE, 0, _("unknown kernel file system %s"), *kernel_fs);
}
seteuid(orig);
return mounted;
}
/* Private functions */
/*===================*/
static int
init_coda(int *dev, dav_run_msgloop_fn *msg_loop, void **mdata)
{
*dev = 0;
int minor = 0;
while (*dev <= 0 && minor < MAX_CODADEVS) {
char *path;
if (asprintf(&path, "%s/%s%i", DAV_DEV_DIR, CODA_DEV_NAME, minor) < 0)
abort();
*dev = open(path, O_RDWR | O_NONBLOCK);
free(path);
++minor;
}
if (*dev <= 0) {
system("/sbin/modprobe coda &>/dev/null");
minor = 0;
while (*dev <= 0 && minor < MAX_CODADEVS) {
char *path;
if (asprintf(&path, "%s/%s%i",
DAV_DEV_DIR, CODA_DEV_NAME, minor) < 0)
abort();
*dev = open(path, O_RDWR | O_NONBLOCK);
if (*dev <= 0) {
if (mknod(path, S_IFCHR, makedev(CODA_MAJOR, minor)) == 0) {
chown(path, 0, 0);
chmod(path, S_IRUSR | S_IWUSR);
*dev = open(path, O_RDWR | O_NONBLOCK);
}
}
free(path);
++minor;
}
}
if (*dev <= 0) {
error(0, 0, _("no free coda device to mount"));
return -1;
}
int version = 0;
ioctl(*dev, CIOC_KERNEL_VERSION, &version);
if (version == 3) {
*msg_loop = dav_coda_loop;
} else {
error(0, 0, _("CODA_KERNEL_VERSION %u not supported"), version);
close(*dev);
return -1;
}
struct coda_mount_data *md = malloc(sizeof(struct coda_mount_data));
if (!md) abort();
md->version = CODA_MOUNT_VERSION;
md->fd = *dev;
*mdata = md;
return 0;
}
static int
init_fuse(int *dev, dav_run_msgloop_fn *msg_loop, void **mdata,
size_t *buf_size, const char *url, const char *mpoint,
unsigned long int mopts, uid_t owner, gid_t group, mode_t mode)
{
char *path;
if (asprintf(&path, "%s/%s", DAV_DEV_DIR, FUSE_DEV_NAME) < 0)
abort();
*dev = open(path, O_RDWR | O_NONBLOCK);
if (*dev <= 0) {
system("/sbin/modprobe fuse &>/dev/null");
*dev = open(path, O_RDWR | O_NONBLOCK);
}
if (*dev <= 0) {
if (mknod(path, S_IFCHR, makedev(FUSE_MAJOR, FUSE_MINOR)) == 0) {
chown(path, 0, 0);
chmod(path, S_IRUSR | S_IWUSR);
*dev = open(path, O_RDWR | O_NONBLOCK);
}
}
free(path);
if (*dev <= 0) {
error(0, 0, _("can't open fuse device"));
return -1;
}
if (*buf_size < (FUSE_MIN_READ_BUFFER + 4096)) {
*buf_size = FUSE_MIN_READ_BUFFER + 4096;
}
#if SIZEOF_VOID_P == 8
if (asprintf((char **) mdata, "fd=%i,rootmode=%o,user_id=%i,group_id=%i,"
"allow_other,max_read=%lu", *dev, mode, owner, group,
*buf_size - 4096) < 0)
abort();
#else
if (asprintf((char **) mdata, "fd=%i,rootmode=%o,user_id=%i,group_id=%i,"
"allow_other,max_read=%u", *dev, mode, owner, group,
*buf_size - 4096) < 0)
abort();
#endif
if (mount(url, mpoint, "fuse", mopts, *mdata) == 0) {
*msg_loop = dav_fuse_loop;
return 0;
}
free(*mdata);
close(*dev);
error(0, 0, _("can't mount using fuse kernel file system"));
return -1;
}