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NetBSD/lib/librefuse/refuse.c

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/* $NetBSD: refuse.c,v 1.114 2022/01/22 08:09:39 pho Exp $ */
/*
* Copyright © 2007 Alistair Crooks. All rights reserved.
* Copyright © 2007 Antti Kantee. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
* OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
* GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
#if !defined(lint)
__RCSID("$NetBSD: refuse.c,v 1.114 2022/01/22 08:09:39 pho Exp $");
#endif /* !lint */
#include <sys/types.h>
#include <assert.h>
#include <err.h>
#include <errno.h>
#include <fuse_internal.h>
#include <fuse_opt.h>
#include <paths.h>
#include <puffs.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#ifdef MULTITHREADED_REFUSE
#include <pthread.h>
#endif
typedef uint64_t fuse_ino_t;
struct refuse_config {
int debug;
char *fsname;
};
#define REFUSE_OPT(t, p, v) \
{ t, offsetof(struct refuse_config, p), v }
static struct fuse_opt refuse_opts[] = {
REFUSE_OPT("debug" , debug , 1),
REFUSE_OPT("fsname=%s", fsname, 0),
FUSE_OPT_END
};
struct puffs_fuse_dirh {
void *dbuf;
struct dirent *d;
size_t reslen;
size_t bufsize;
};
struct refusenode {
struct fuse_file_info file_info;
struct puffs_fuse_dirh dirh;
int opencount;
int flags;
};
#define RN_ROOT 0x01
#define RN_OPEN 0x02 /* XXX: could just use opencount */
static int fuse_setattr(struct fuse *, struct puffs_node *,
const char *, const struct vattr *);
static struct puffs_node *
newrn(struct puffs_usermount *pu)
{
struct puffs_node *pn;
struct refusenode *rn;
if ((rn = calloc(1, sizeof(*rn))) == NULL) {
err(EXIT_FAILURE, "newrn");
}
pn = puffs_pn_new(pu, rn);
return pn;
}
static void
nukern(struct puffs_node *pn)
{
struct refusenode *rn = pn->pn_data;
free(rn->dirh.dbuf);
free(rn);
puffs_pn_put(pn);
}
/* XXX - not threadsafe */
static ino_t fakeino = 3;
/***************** start of pthread context routines ************************/
/*
* Notes on fuse_context:
* we follow fuse's lead and use the pthread specific information to hold
* a reference to the fuse_context structure for this thread.
*/
#ifdef MULTITHREADED_REFUSE
static pthread_mutex_t context_mutex = PTHREAD_MUTEX_INITIALIZER;
static pthread_key_t context_key;
static unsigned long context_refc;
#endif
/* return the fuse_context struct related to this thread */
struct fuse_context *
fuse_get_context(void)
{
#ifdef MULTITHREADED_REFUSE
struct fuse_context *ctxt;
if ((ctxt = pthread_getspecific(context_key)) == NULL) {
if ((ctxt = calloc(1, sizeof(struct fuse_context))) == NULL) {
abort();
}
pthread_setspecific(context_key, ctxt);
}
return ctxt;
#else
static struct fuse_context fcon;
return &fcon;
#endif
}
/* used as a callback function */
#ifdef MULTITHREADED_REFUSE
static void
free_context(void *ctxt)
{
free(ctxt);
}
#endif
/*
* Create the pthread key. The reason for the complexity is to
* enable use of multiple fuse instances within a single process.
*/
static int
create_context_key(void)
{
#ifdef MULTITHREADED_REFUSE
int rv;
rv = pthread_mutex_lock(&context_mutex);
assert(rv == 0);
if (context_refc == 0) {
if (pthread_key_create(&context_key, free_context) != 0) {
warnx("create_context_key: pthread_key_create failed");
pthread_mutex_unlock(&context_mutex);
return 0;
}
}
context_refc += 1;
pthread_mutex_unlock(&context_mutex);
return 1;
#else
return 1;
#endif
}
/* struct fuse_context is potentially reused among different
* invocations of fuse_new() / fuse_destroy() pair. Clear its content
* on fuse_destroy() so that no dangling pointers remain in the
* context. */
static void
clear_context(void)
{
struct fuse_context *ctx;
ctx = fuse_get_context();
memset(ctx, 0, sizeof(*ctx));
}
static void
delete_context_key(void)
{
#ifdef MULTITHREADED_REFUSE
pthread_mutex_lock(&context_mutex);
/* If we are the last fuse instances using the key, delete it */
if (--context_refc == 0) {
free(pthread_getspecific(context_key));
pthread_key_delete(context_key);
}
pthread_mutex_unlock(&context_mutex);
#endif
}
/* set the uid and gid of the calling process in the current fuse context */
static void
set_fuse_context_uid_gid(const struct puffs_cred *cred)
{
struct fuse_context *fusectx;
uid_t uid;
gid_t gid;
fusectx = fuse_get_context();
if (puffs_cred_getuid(cred, &uid) == 0) {
fusectx->uid = uid;
}
if (puffs_cred_getgid(cred, &gid) == 0) {
fusectx->gid = gid;
}
}
/* set the pid of the calling process in the current fuse context */
static void
set_fuse_context_pid(struct puffs_usermount *pu)
{
struct puffs_cc *pcc = puffs_cc_getcc(pu);
struct fuse_context *fusectx;
fusectx = fuse_get_context();
puffs_cc_getcaller(pcc, &fusectx->pid, NULL);
}
/***************** end of pthread context routines ************************/
#define DIR_CHUNKSIZE 4096
static int
fill_dirbuf(struct puffs_fuse_dirh *dh, const char *name, ino_t dino,
uint8_t dtype)
{
/* initial? */
if (dh->bufsize == 0) {
if ((dh->dbuf = calloc(1, DIR_CHUNKSIZE)) == NULL) {
abort();
}
dh->d = dh->dbuf;
dh->reslen = dh->bufsize = DIR_CHUNKSIZE;
}
if (puffs_nextdent(&dh->d, name, dino, dtype, &dh->reslen)) {
return 0;
}
/* try to increase buffer space */
dh->dbuf = realloc(dh->dbuf, dh->bufsize + DIR_CHUNKSIZE);
if (dh->dbuf == NULL) {
abort();
}
dh->d = (void *)((uint8_t *)dh->dbuf + (dh->bufsize - dh->reslen));
dh->reslen += DIR_CHUNKSIZE;
dh->bufsize += DIR_CHUNKSIZE;
return !puffs_nextdent(&dh->d, name, dino, dtype, &dh->reslen);
}
/* ARGSUSED3 */
/* XXX: I have no idea how "off" is supposed to be used */
static int
puffs_fuse_fill_dir(void *buf, const char *name,
const struct stat *stbuf, off_t off, enum fuse_fill_dir_flags flags)
{
struct puffs_fuse_dirh *deh = buf;
ino_t dino;
uint8_t dtype;
if (stbuf == NULL) {
dtype = DT_UNKNOWN;
dino = fakeino++;
} else {
dtype = (uint8_t)puffs_vtype2dt(puffs_mode2vt(stbuf->st_mode));
dino = stbuf->st_ino;
/*
* Some FUSE file systems like to always use 0 as the
* inode number. Our readdir() doesn't like to show
* directory entries with inode number 0 ==> workaround.
*/
if (dino == 0) {
dino = fakeino++;
}
}
return fill_dirbuf(deh, name, dino, dtype);
}
/* ARGSUSED1 */
static int
fuse_getattr(struct fuse *fuse, struct puffs_node *pn, const char *path,
struct vattr *va)
{
struct refusenode *rn = pn->pn_data;
struct fuse_file_info *fi = rn->opencount > 0 ? &rn->file_info : NULL;
struct stat st;
int ret;
/* wrap up return code */
memset(&st, 0, sizeof(st));
ret = fuse_fs_getattr_v30(fuse->fs, path, &st, fi);
if (ret == 0) {
if (st.st_blksize == 0)
st.st_blksize = DEV_BSIZE;
puffs_stat2vattr(va, &st);
}
return -ret;
}
/* utility function to set various elements of the attribute */
static int
fuse_setattr(struct fuse *fuse, struct puffs_node *pn, const char *path,
const struct vattr *va)
{
struct refusenode *rn = pn->pn_data;
struct fuse_file_info *fi = rn->opencount > 0 ? &rn->file_info : NULL;
mode_t mode;
uid_t uid;
gid_t gid;
int error, ret;
error = 0;
mode = va->va_mode;
uid = va->va_uid;
gid = va->va_gid;
if (mode != (mode_t)PUFFS_VNOVAL) {
ret = fuse_fs_chmod_v30(fuse->fs, path, mode, fi);
if (ret)
error = ret;
}
if (uid != (uid_t)PUFFS_VNOVAL || gid != (gid_t)PUFFS_VNOVAL) {
ret = fuse_fs_chown_v30(fuse->fs, path, uid, gid, fi);
if (ret)
error = ret;
}
if (va->va_atime.tv_sec != (time_t)PUFFS_VNOVAL
|| va->va_mtime.tv_sec != (long)PUFFS_VNOVAL) {
struct timespec tv[2];
tv[0].tv_sec = va->va_atime.tv_sec;
tv[0].tv_nsec = va->va_atime.tv_nsec;
tv[1].tv_sec = va->va_mtime.tv_sec;
tv[1].tv_nsec = va->va_mtime.tv_nsec;
ret = fuse_fs_utimens_v30(fuse->fs, path, tv, fi);
if (ret)
error = ret;
}
if (va->va_size != (u_quad_t)PUFFS_VNOVAL) {
ret = fuse_fs_truncate_v30(fuse->fs, path, (off_t)va->va_size, fi);
if (ret)
error = ret;
}
/* XXX: no reflection with reality */
puffs_setvattr(&pn->pn_va, va);
return -error;
}
static int
fuse_newnode(struct puffs_usermount *pu, const char *path,
const struct vattr *va, struct fuse_file_info *fi,
struct puffs_newinfo *pni, struct puffs_node **pn_new)
{
struct puffs_node *pn;
struct refusenode *rn;
struct vattr newva;
struct fuse *fuse;
fuse = puffs_getspecific(pu);
/* fix up nodes */
pn = newrn(pu);
if (pn == NULL) {
if (va->va_type == VDIR) {
fuse_fs_rmdir(fuse->fs, path);
} else {
fuse_fs_unlink(fuse->fs, path);
}
return ENOMEM;
}
fuse_setattr(fuse, pn, path, va);
if (fuse_getattr(fuse, pn, path, &newva) == 0)
puffs_setvattr(&pn->pn_va, &newva);
rn = pn->pn_data;
if (fi)
memcpy(&rn->file_info, fi, sizeof(struct fuse_file_info));
puffs_newinfo_setcookie(pni, pn);
if (pn_new)
*pn_new = pn;
return 0;
}
/* operation wrappers start here */
/* lookup the path */
/* ARGSUSED1 */
static int
puffs_fuse_node_lookup(struct puffs_usermount *pu, void *opc,
struct puffs_newinfo *pni, const struct puffs_cn *pcn)
{
struct puffs_node *pn_res;
struct stat st;
struct fuse *fuse;
const char *path = PCNPATH(pcn);
int ret;
fuse = puffs_getspecific(pu);
set_fuse_context_uid_gid(pcn->pcn_cred);
ret = fuse_fs_getattr_v30(fuse->fs, path, &st, NULL);
if (ret != 0) {
return -ret;
}
/* XXX: fiXXXme unconst */
pn_res = puffs_pn_nodewalk(pu, puffs_path_walkcmp,
__UNCONST(&pcn->pcn_po_full));
if (pn_res == NULL) {
pn_res = newrn(pu);
if (pn_res == NULL)
return errno;
puffs_stat2vattr(&pn_res->pn_va, &st);
}
puffs_newinfo_setcookie(pni, pn_res);
puffs_newinfo_setvtype(pni, pn_res->pn_va.va_type);
puffs_newinfo_setsize(pni, (voff_t)pn_res->pn_va.va_size);
puffs_newinfo_setrdev(pni, pn_res->pn_va.va_rdev);
return 0;
}
/* get attributes for the path name */
/* ARGSUSED3 */
static int
puffs_fuse_node_getattr(struct puffs_usermount *pu, void *opc, struct vattr *va,
const struct puffs_cred *pcr)
{
struct puffs_node *pn = opc;
struct fuse *fuse;
const char *path = PNPATH(pn);
fuse = puffs_getspecific(pu);
set_fuse_context_uid_gid(pcr);
return fuse_getattr(fuse, pn, path, va);
}
/* read the contents of the symbolic link */
/* ARGSUSED2 */
static int
puffs_fuse_node_readlink(struct puffs_usermount *pu, void *opc,
const struct puffs_cred *cred, char *linkname, size_t *linklen)
{
struct puffs_node *pn = opc;
struct fuse *fuse;
const char *path = PNPATH(pn), *p;
int ret;
fuse = puffs_getspecific(pu);
set_fuse_context_uid_gid(cred);
/* wrap up return code */
ret = fuse_fs_readlink(fuse->fs, path, linkname, *linklen);
if (ret == 0) {
p = memchr(linkname, '\0', *linklen);
if (!p)
return EINVAL;
*linklen = (size_t)(p - linkname);
}
return -ret;
}
/* make the special node */
/* ARGSUSED1 */
static int
puffs_fuse_node_mknod(struct puffs_usermount *pu, void *opc,
struct puffs_newinfo *pni, const struct puffs_cn *pcn,
const struct vattr *va)
{
struct fuse *fuse;
mode_t mode;
const char *path = PCNPATH(pcn);
int ret;
fuse = puffs_getspecific(pu);
set_fuse_context_uid_gid(pcn->pcn_cred);
/* wrap up return code */
mode = puffs_addvtype2mode(va->va_mode, va->va_type);
ret = fuse_fs_mknod(fuse->fs, path, mode, va->va_rdev);
if (ret == 0) {
ret = fuse_newnode(pu, path, va, NULL, pni, NULL);
}
return -ret;
}
/* make a directory */
/* ARGSUSED1 */
static int
puffs_fuse_node_mkdir(struct puffs_usermount *pu, void *opc,
struct puffs_newinfo *pni, const struct puffs_cn *pcn,
const struct vattr *va)
{
struct fuse *fuse;
mode_t mode = va->va_mode;
const char *path = PCNPATH(pcn);
int ret;
fuse = puffs_getspecific(pu);
set_fuse_context_uid_gid(pcn->pcn_cred);
/* wrap up return code */
ret = fuse_fs_mkdir(fuse->fs, path, mode);
if (ret == 0) {
ret = fuse_newnode(pu, path, va, NULL, pni, NULL);
}
return -ret;
}
/*
* create a regular file
*
* since linux/fuse sports using mknod for creating regular files
* instead of having a separate call for it in some versions, if
* we don't have create, just jump to op->mknod.
*/
/*ARGSUSED1*/
static int
puffs_fuse_node_create(struct puffs_usermount *pu, void *opc,
struct puffs_newinfo *pni, const struct puffs_cn *pcn,
const struct vattr *va)
{
struct fuse *fuse;
struct fuse_file_info fi;
struct puffs_node *pn;
mode_t mode = va->va_mode;
const char *path = PCNPATH(pcn);
int ret, created;
fuse = puffs_getspecific(pu);
set_fuse_context_uid_gid(pcn->pcn_cred);
memset(&fi, 0, sizeof(fi));
/* In puffs "create" and "open" are two separate operations
* with atomicity achieved by locking the parent vnode. In
* fuse, on the other hand, "create" is actually a
* create-and-open-atomically and the open flags (O_RDWR,
* O_APPEND, ...) are passed via fi.flags. So the only way to
* emulate the fuse semantics is to open the file with dummy
* flags and then immediately close it.
*
* You might think that we could simply use fuse->op.mknod all
* the time but no, that's not possible because most file
* systems nowadays expect op.mknod to be called only for
* non-regular files and many don't even support it. */
created = 0;
fi.flags = O_WRONLY | O_CREAT | O_EXCL;
ret = fuse_fs_create(fuse->fs, path, mode | S_IFREG, &fi);
if (ret == 0) {
created = 1;
}
else if (ret == -ENOSYS) {
ret = fuse_fs_mknod(fuse->fs, path, mode | S_IFREG, 0);
}
if (ret == 0) {
ret = fuse_newnode(pu, path, va, &fi, pni, &pn);
/* sweet.. create also open the file */
if (created) {
struct refusenode *rn = pn->pn_data;
/* The return value of op.release is expected to be
* discarded. */
(void)fuse_fs_release(fuse->fs, path, &rn->file_info);
}
}
return -ret;
}
/* remove the directory entry */
/* ARGSUSED1 */
static int
puffs_fuse_node_remove(struct puffs_usermount *pu, void *opc, void *targ,
const struct puffs_cn *pcn)
{
struct puffs_node *pn_targ = targ;
struct fuse *fuse;
const char *path = PNPATH(pn_targ);
int ret;
fuse = puffs_getspecific(pu);
set_fuse_context_uid_gid(pcn->pcn_cred);
/* wrap up return code */
ret = fuse_fs_unlink(fuse->fs, path);
return -ret;
}
/* remove the directory */
/* ARGSUSED1 */
static int
puffs_fuse_node_rmdir(struct puffs_usermount *pu, void *opc, void *targ,
const struct puffs_cn *pcn)
{
struct puffs_node *pn_targ = targ;
struct fuse *fuse;
const char *path = PNPATH(pn_targ);
int ret;
fuse = puffs_getspecific(pu);
set_fuse_context_uid_gid(pcn->pcn_cred);
/* wrap up return code */
ret = fuse_fs_rmdir(fuse->fs, path);
return -ret;
}
/* create a symbolic link */
/* ARGSUSED1 */
static int
puffs_fuse_node_symlink(struct puffs_usermount *pu, void *opc,
struct puffs_newinfo *pni, const struct puffs_cn *pcn_src,
const struct vattr *va, const char *link_target)
{
struct fuse *fuse;
const char *path = PCNPATH(pcn_src);
int ret;
fuse = puffs_getspecific(pu);
set_fuse_context_uid_gid(pcn_src->pcn_cred);
/* wrap up return code */
ret = fuse_fs_symlink(fuse->fs, link_target, path);
if (ret == 0) {
ret = fuse_newnode(pu, path, va, NULL, pni, NULL);
}
return -ret;
}
/* rename a directory entry */
/* ARGSUSED1 */
static int
puffs_fuse_node_rename(struct puffs_usermount *pu, void *opc, void *src,
const struct puffs_cn *pcn_src, void *targ_dir, void *targ,
const struct puffs_cn *pcn_targ)
{
struct fuse *fuse;
const char *path_src = PCNPATH(pcn_src);
const char *path_dest = PCNPATH(pcn_targ);
int ret;
fuse = puffs_getspecific(pu);
set_fuse_context_uid_gid(pcn_targ->pcn_cred);
ret = fuse_fs_rename_v30(fuse->fs, path_src, path_dest, 0);
return -ret;
}
/* create a link in the file system */
/* ARGSUSED1 */
static int
puffs_fuse_node_link(struct puffs_usermount *pu, void *opc, void *targ,
const struct puffs_cn *pcn)
{
struct puffs_node *pn = targ;
struct fuse *fuse;
int ret;
fuse = puffs_getspecific(pu);
set_fuse_context_uid_gid(pcn->pcn_cred);
/* wrap up return code */
ret = fuse_fs_link(fuse->fs, PNPATH(pn), PCNPATH(pcn));
return -ret;
}
/*
* fuse's regular interface provides chmod(), chown(), utimes()
* and truncate() + some variations, so try to fit the square block
* in the circle hole and the circle block .... something like that
*/
/* ARGSUSED3 */
static int
puffs_fuse_node_setattr(struct puffs_usermount *pu, void *opc,
const struct vattr *va, const struct puffs_cred *pcr)
{
struct puffs_node *pn = opc;
struct fuse *fuse;
const char *path = PNPATH(pn);
fuse = puffs_getspecific(pu);
set_fuse_context_uid_gid(pcr);
return fuse_setattr(fuse, pn, path, va);
}
static int
puffs_fuse_node_pathconf(struct puffs_usermount *pu, void *opc,
int name, __register_t *retval)
{
/* Returning EINVAL for pathconf(2) means that this filesystem
* does not support an association of the given name with the
* file. This is necessary because the default error code
* returned by the puffs kernel module (ENOTSUPP) is not
* suitable for an errno from pathconf(2), and "ls -l"
* complains about it. */
return EINVAL;
}
/* ARGSUSED2 */
static int
puffs_fuse_node_open(struct puffs_usermount *pu, void *opc, int mode,
const struct puffs_cred *cred)
{
struct puffs_node *pn = opc;
struct refusenode *rn = pn->pn_data;
struct fuse_file_info *fi = &rn->file_info;
struct fuse *fuse;
const char *path = PNPATH(pn);
int ret;
fuse = puffs_getspecific(pu);
set_fuse_context_uid_gid(cred);
/* if open, don't open again, lest risk nuking file private info */
if (rn->flags & RN_OPEN) {
rn->opencount++;
return 0;
}
/* OFLAGS(), need to convert FREAD/FWRITE to O_RD/WR */
fi->flags = (mode & ~(O_CREAT | O_EXCL | O_TRUNC)) - 1;
if (pn->pn_va.va_type == VDIR) {
ret = fuse_fs_opendir(fuse->fs, path, fi);
} else {
ret = fuse_fs_open(fuse->fs, path, fi);
}
if (ret == 0) {
rn->flags |= RN_OPEN;
rn->opencount++;
}
return -ret;
}
/* ARGSUSED2 */
static int
puffs_fuse_node_close(struct puffs_usermount *pu, void *opc, int fflag,
const struct puffs_cred *pcr)
{
struct puffs_node *pn = opc;
struct refusenode *rn = pn->pn_data;
struct fuse *fuse;
struct fuse_file_info *fi;
const char *path = PNPATH(pn);
int ret;
fuse = puffs_getspecific(pu);
fi = &rn->file_info;
ret = 0;
set_fuse_context_uid_gid(pcr);
if (rn->flags & RN_OPEN) {
if (pn->pn_va.va_type == VDIR) {
ret = fuse_fs_releasedir(fuse->fs, path, fi);
} else {
ret = fuse_fs_release(fuse->fs, path, fi);
}
}
rn->flags &= ~RN_OPEN;
rn->opencount--;
return ret;
}
/* read some more from the file */
/* ARGSUSED5 */
static int
puffs_fuse_node_read(struct puffs_usermount *pu, void *opc, uint8_t *buf,
off_t offset, size_t *resid, const struct puffs_cred *pcr,
int ioflag)
{
struct puffs_node *pn = opc;
struct refusenode *rn = pn->pn_data;
struct fuse *fuse;
const char *path = PNPATH(pn);
size_t maxread;
int ret;
fuse = puffs_getspecific(pu);
set_fuse_context_uid_gid(pcr);
maxread = *resid;
if (maxread > (size_t)((off_t)pn->pn_va.va_size - offset)) {
/*LINTED*/
maxread = (size_t)((off_t)pn->pn_va.va_size - offset);
}
if (maxread == 0)
return 0;
ret = fuse_fs_read(fuse->fs, path, (char *)buf, maxread, offset,
&rn->file_info);
if (ret > 0) {
*resid -= (size_t)ret;
ret = 0;
}
return -ret;
}
/* write to the file */
/* ARGSUSED0 */
static int
puffs_fuse_node_write(struct puffs_usermount *pu, void *opc, uint8_t *buf,
off_t offset, size_t *resid, const struct puffs_cred *pcr,
int ioflag)
{
struct puffs_node *pn = opc;
struct refusenode *rn = pn->pn_data;
struct fuse *fuse;
const char *path = PNPATH(pn);
int ret;
fuse = puffs_getspecific(pu);
set_fuse_context_uid_gid(pcr);
if (ioflag & PUFFS_IO_APPEND)
offset = (off_t)pn->pn_va.va_size;
ret = fuse_fs_write(fuse->fs, path, (char *)buf, *resid, offset,
&rn->file_info);
if (ret >= 0) {
if ((uint64_t)(offset + ret) > pn->pn_va.va_size)
pn->pn_va.va_size = (u_quad_t)(offset + ret);
*resid -= (size_t)ret;
ret = (*resid == 0) ? 0 : ENOSPC;
} else {
ret = -ret;
}
return ret;
}
/* ARGSUSED3 */
static int
puffs_fuse_node_readdir(struct puffs_usermount *pu, void *opc,
struct dirent *dent, off_t *readoff, size_t *reslen,
const struct puffs_cred *pcr, int *eofflag,
off_t *cookies, size_t *ncookies)
{
struct puffs_node *pn = opc;
struct refusenode *rn = pn->pn_data;
struct puffs_fuse_dirh *dirh;
struct fuse *fuse;
struct dirent *fromdent;
const char *path = PNPATH(pn);
int ret;
fuse = puffs_getspecific(pu);
set_fuse_context_uid_gid(pcr);
if (pn->pn_va.va_type != VDIR)
return ENOTDIR;
dirh = &rn->dirh;
/*
* if we are starting from the beginning, slurp entire directory
* into our buffers
*/
if (*readoff == 0) {
/* free old buffers */
free(dirh->dbuf);
memset(dirh, 0, sizeof(struct puffs_fuse_dirh));
ret = fuse_fs_readdir_v30(
fuse->fs, path, dirh, puffs_fuse_fill_dir,
0, &rn->file_info, (enum fuse_readdir_flags)0);
if (ret)
return -ret;
}
/* Both op.readdir and op.getdir read full directory */
*eofflag = 1;
/* now, stuff results into the kernel buffers */
while (*readoff < (off_t)(dirh->bufsize - dirh->reslen)) {
/*LINTED*/
fromdent = (struct dirent *)((uint8_t *)dirh->dbuf + *readoff);
if (*reslen < _DIRENT_SIZE(fromdent))
break;
memcpy(dent, fromdent, _DIRENT_SIZE(fromdent));
*readoff += (off_t)_DIRENT_SIZE(fromdent);
*reslen -= _DIRENT_SIZE(fromdent);
dent = _DIRENT_NEXT(dent);
}
return 0;
}
/* ARGSUSED */
static int
puffs_fuse_node_reclaim(struct puffs_usermount *pu, void *opc)
{
struct puffs_node *pn = opc;
nukern(pn);
return 0;
}
/* ARGSUSED1 */
static int
puffs_fuse_fs_unmount(struct puffs_usermount *pu, int flags)
{
struct fuse *fuse;
fuse = puffs_getspecific(pu);
fuse_fs_destroy(fuse->fs);
return 0;
}
/* ARGSUSED0 */
static int
puffs_fuse_fs_sync(struct puffs_usermount *pu, int flags,
const struct puffs_cred *cr)
{
set_fuse_context_uid_gid(cr);
return 0;
}
/* ARGSUSED2 */
static int
puffs_fuse_fs_statvfs(struct puffs_usermount *pu, struct puffs_statvfs *svfsb)
{
struct fuse *fuse;
int ret;
struct statvfs sb;
/* fuse_fs_statfs() is special: it returns 0 even if the
* filesystem doesn't support statfs. So clear the struct
* before calling it. */
memset(&sb, 0, sizeof(sb));
fuse = puffs_getspecific(pu);
ret = fuse_fs_statfs(fuse->fs, PNPATH(puffs_getroot(pu)), &sb);
if (ret == 0)
statvfs_to_puffs_statvfs(&sb, svfsb);
return -ret;
}
/* End of puffs_fuse operations */
struct fuse *
__fuse_setup(int argc, char* argv[],
const void* op, int op_version, void* user_data,
struct fuse_cmdline_opts* opts)
{
struct fuse_args args = FUSE_ARGS_INIT(argc, argv);
struct fuse *fuse = NULL;
/* parse low-level options */
if (fuse_parse_cmdline_v30(&args, opts) != 0)
return NULL;
if (opts->show_version) {
fuse_lowlevel_version();
goto free_args;
}
if (opts->show_help) {
switch (opts->show_help) {
case REFUSE_SHOW_HELP_FULL:
if (args.argv[0] != NULL && args.argv[0][0] != '\0') {
/* argv[0] being empty means that the application doesn't
* want us to print the usage string.
*/
printf("Usage: %s [options] mountpoint\n\n", args.argv[0]);
}
break;
case REFUSE_SHOW_HELP_NO_HEADER:
break;
}
fuse_cmdline_help();
goto free_args;
}
if (opts->mountpoint == NULL) {
fprintf(stderr, "fuse: no mountpoint specified\n");
goto free_args;
}
if (opts->debug) {
if (fuse_opt_add_arg(&args, "-odebug") != 0)
goto free_args;
}
fuse = __fuse_new(&args, op, op_version, user_data);
if (fuse == NULL)
goto free_args;
if (fuse_daemonize(opts->foreground) != 0)
goto destroy;
if (fuse_mount_v30(fuse, opts->mountpoint) != 0)
goto destroy;
if (__fuse_set_signal_handlers(fuse) != 0) {
warn("%s: Failed to set signal handlers", __func__);
goto destroy;
}
goto done;
destroy:
fuse_destroy_v30(fuse);
fuse = NULL;
free_args:
free(opts->mountpoint);
done:
fuse_opt_free_args(&args);
return fuse;
}
void
__fuse_teardown(struct fuse* fuse)
{
if (__fuse_remove_signal_handlers(fuse) != 0)
warn("%s: Failed to restore signal handlers", __func__);
fuse_unmount_v30(fuse);
}
/* ARGSUSED3 */
int
__fuse_main(int argc, char **argv, const void *op,
int op_version, void *user_data)
{
struct fuse_cmdline_opts opts;
struct fuse *fuse;
int rv;
fuse = __fuse_setup(argc, argv, op, op_version, user_data, &opts);
if (fuse == NULL)
return -1;
rv = fuse_loop(fuse);
__fuse_teardown(fuse);
free(opts.mountpoint);
return rv;
}
int __fuse_mount(struct fuse *fuse, const char *mountpoint)
{
struct puffs_pathobj *po_root;
struct puffs_node *pn_root;
struct refusenode *rn_root;
struct puffs_statvfs svfsb;
pn_root = newrn(fuse->pu);
puffs_setroot(fuse->pu, pn_root);
rn_root = pn_root->pn_data;
rn_root->flags |= RN_ROOT;
po_root = puffs_getrootpathobj(fuse->pu);
if ((po_root->po_path = strdup("/")) == NULL)
err(1, "fuse_mount");
po_root->po_len = 1;
puffs_path_buildhash(fuse->pu, po_root);
/* sane defaults */
puffs_vattr_null(&pn_root->pn_va);
pn_root->pn_va.va_type = VDIR;
pn_root->pn_va.va_mode = 0755;
/* It might be tempting to call op.getattr("/") here to
* populate pn_root->pa_va, but that would mean invoking an
* operation callback without initializing the filesystem. We
* cannot call op.init() either, because that is supposed to
* be called right before entering the main loop. */
puffs_set_prepost(fuse->pu, set_fuse_context_pid, NULL);
puffs_zerostatvfs(&svfsb);
if (puffs_mount(fuse->pu, mountpoint, MNT_NODEV | MNT_NOSUID, pn_root) == -1) {
err(EXIT_FAILURE, "puffs_mount: directory \"%s\"", mountpoint);
}
return 0;
}
int fuse_daemonize(int foreground)
{
/* There is an impedance mismatch here: FUSE wants to
* daemonize the process without any contexts but puffs wants
* one. */
struct fuse *fuse = fuse_get_context()->fuse;
if (!fuse)
/* FUSE would probably allow this, but we cannot. */
errx(EXIT_FAILURE,
"%s: librefuse doesn't allow calling"
" this function before fuse_new().", __func__);
if (!foreground)
return puffs_daemon(fuse->pu, 0, 0);
return 0;
}
struct fuse *
__fuse_new(struct fuse_args *args, const void *op, int op_version, void* user_data)
{
struct refuse_config config;
struct puffs_usermount *pu;
struct fuse_context *fusectx;
struct puffs_ops *pops;
struct fuse *fuse;
uint32_t puffs_flags;
/* parse refuse options */
memset(&config, 0, sizeof(config));
if (fuse_opt_parse(args, &config, refuse_opts, NULL) == -1)
return NULL;
if ((fuse = calloc(1, sizeof(*fuse))) == NULL) {
err(EXIT_FAILURE, "fuse_new");
}
/* grab the pthread context key */
if (!create_context_key()) {
free(config.fsname);
free(fuse);
return NULL;
}
/* Create the base filesystem layer. */
fuse->fs = __fuse_fs_new(op, op_version, user_data);
fusectx = fuse_get_context();
fusectx->fuse = fuse;
fusectx->uid = 0;
fusectx->gid = 0;
fusectx->pid = 0;
fusectx->private_data = user_data;
/* initialise the puffs operations structure */
PUFFSOP_INIT(pops);
PUFFSOP_SET(pops, puffs_fuse, fs, sync);
PUFFSOP_SET(pops, puffs_fuse, fs, statvfs);
PUFFSOP_SET(pops, puffs_fuse, fs, unmount);
/*
* XXX: all of these don't possibly need to be
* unconditionally set
*/
PUFFSOP_SET(pops, puffs_fuse, node, lookup);
PUFFSOP_SET(pops, puffs_fuse, node, getattr);
PUFFSOP_SET(pops, puffs_fuse, node, setattr);
PUFFSOP_SET(pops, puffs_fuse, node, pathconf);
PUFFSOP_SET(pops, puffs_fuse, node, readdir);
PUFFSOP_SET(pops, puffs_fuse, node, readlink);
PUFFSOP_SET(pops, puffs_fuse, node, mknod);
PUFFSOP_SET(pops, puffs_fuse, node, create);
PUFFSOP_SET(pops, puffs_fuse, node, remove);
PUFFSOP_SET(pops, puffs_fuse, node, mkdir);
PUFFSOP_SET(pops, puffs_fuse, node, rmdir);
PUFFSOP_SET(pops, puffs_fuse, node, symlink);
PUFFSOP_SET(pops, puffs_fuse, node, rename);
PUFFSOP_SET(pops, puffs_fuse, node, link);
PUFFSOP_SET(pops, puffs_fuse, node, open);
PUFFSOP_SET(pops, puffs_fuse, node, close);
PUFFSOP_SET(pops, puffs_fuse, node, read);
PUFFSOP_SET(pops, puffs_fuse, node, write);
PUFFSOP_SET(pops, puffs_fuse, node, reclaim);
puffs_flags = PUFFS_FLAG_BUILDPATH
| PUFFS_FLAG_HASHPATH
| PUFFS_KFLAG_NOCACHE;
if (config.debug)
puffs_flags |= PUFFS_FLAG_OPDUMP;
pu = puffs_init(pops, _PATH_PUFFS, config.fsname, fuse, puffs_flags);
if (pu == NULL) {
err(EXIT_FAILURE, "puffs_init");
}
fuse->pu = pu;
free(config.fsname);
return fuse;
}
int
fuse_loop(struct fuse *fuse)
{
struct fuse_conn_info conn;
struct fuse_config cfg;
/* struct fuse_conn_info is a part of the FUSE API so we must
* expose it to users, but we currently don't use them at
* all. The same goes for struct fuse_config. */
memset(&conn, 0, sizeof(conn));
memset(&cfg, 0, sizeof(cfg));
fuse_fs_init_v30(fuse->fs, &conn, &cfg);
return puffs_mainloop(fuse->pu);
}
int
__fuse_loop_mt(struct fuse *fuse,
struct fuse_loop_config *config __attribute__((__unused__)))
{
/* TODO: Implement a proper multi-threaded loop. */
return fuse_loop(fuse);
}
void
__fuse_destroy(struct fuse *fuse)
{
/*
* TODO: needs to assert the fs is quiescent, i.e. no other
* threads exist
*/
clear_context();
delete_context_key();
/* XXXXXX: missing stuff */
free(fuse);
}
void
fuse_exit(struct fuse *fuse)
{
/* XXX: puffs_exit() is WRONG */
if (fuse->dead == 0)
puffs_exit(fuse->pu, 1);
fuse->dead = 1;
}
/*
* XXX: obviously not the most perfect of functions, but needs some
* puffs tweaking for a better tomorrow
*/
void
__fuse_unmount(struct fuse *fuse)
{
/* XXX: puffs_exit() is WRONG */
if (fuse->dead == 0)
puffs_exit(fuse->pu, 1);
fuse->dead = 1;
}
void
fuse_lib_help(struct fuse_args *args __attribute__((__unused__)))
{
fuse_cmdline_help();
}
int
fuse_interrupted(void)
{
/* ReFUSE doesn't support request interruption at the
* moment. */
return 0;
}
int
fuse_invalidate_path(struct fuse *fuse __attribute__((__unused__)),
const char *path __attribute__((__unused__)))
{
/* ReFUSE doesn't cache anything at the moment. No need to do
* anything. */
return -ENOENT;
}
int
fuse_version(void)
{
return _REFUSE_VERSION_;
}
const char *
fuse_pkgversion(void)
{
return "ReFUSE " ___STRING(_REFUSE_MAJOR_VERSION_)
"." ___STRING(_REFUSE_MINOR_VERSION_);
}
int
fuse_getgroups(int size, gid_t list[])
{
/* XXX: In order to implement this, we need to save a pointer
* to struct puffs_cred in struct fuse upon entering a puffs
* callback, and set it back to NULL upon leaving it. Then we
* can use puffs_cred_getgroups(3) here. */
return -ENOSYS;
}
int
fuse_start_cleanup_thread(struct fuse *fuse)
{
/* XXX: ReFUSE doesn't support -oremember at the moment. */
return 0;
}
void
fuse_stop_cleanup_thread(struct fuse *fuse) {
/* XXX: ReFUSE doesn't support -oremember at the moment. */
}
int
fuse_clean_cache(struct fuse *fuse) {
/* XXX: ReFUSE doesn't support -oremember at the moment. */
return 3600;
}
/* This is a legacy function that has been removed from the FUSE API,
* but is defined here because it needs to access refuse_opts. */
int
fuse_is_lib_option(const char *opt)
{
return fuse_opt_match(refuse_opts, opt);
}
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