/*
* linux/fs/nfs/nfs2xdr.c
*
* XDR functions to encode/decode NFS RPC arguments and results.
*
* Copyright (C) 1992, 1993, 1994 Rick Sladkey
* Copyright (C) 1996 Olaf Kirch
* 04 Aug 1998 Ion Badulescu <ionut@cs.columbia.edu>
* FIFO's need special handling in NFSv2
*/
#include <linux/param.h>
#include <linux/time.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/utsname.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/in.h>
#include <linux/pagemap.h>
#include <linux/proc_fs.h>
#include <linux/sunrpc/clnt.h>
#include <linux/nfs.h>
#include <linux/nfs2.h>
#include <linux/nfs_fs.h>
#define NFSDBG_FACILITY NFSDBG_XDR
/* #define NFS_PARANOIA 1 */
extern int nfs_stat_to_errno(int stat);
/* Mapping from NFS error code to "errno" error code. */
#define errno_NFSERR_IO EIO
/*
* Declare the space requirements for NFS arguments and replies as
* number of 32bit-words
*/
#define NFS_fhandle_sz (8)
#define NFS_sattr_sz (8)
#define NFS_filename_sz (1+(NFS2_MAXNAMLEN>>2))
#define NFS_path_sz (1+(NFS2_MAXPATHLEN>>2))
#define NFS_fattr_sz (17)
#define NFS_info_sz (5)
#define NFS_entry_sz (NFS_filename_sz+3)
#define NFS_diropargs_sz (NFS_fhandle_sz+NFS_filename_sz)
#define NFS_sattrargs_sz (NFS_fhandle_sz+NFS_sattr_sz)
#define NFS_readlinkargs_sz (NFS_fhandle_sz)
#define NFS_readargs_sz (NFS_fhandle_sz+3)
#define NFS_writeargs_sz (NFS_fhandle_sz+4)
#define NFS_createargs_sz (NFS_diropargs_sz+NFS_sattr_sz)
#define NFS_renameargs_sz (NFS_diropargs_sz+NFS_diropargs_sz)
#define NFS_linkargs_sz (NFS_fhandle_sz+NFS_diropargs_sz)
#define NFS_symlinkargs_sz (NFS_diropargs_sz+NFS_path_sz+NFS_sattr_sz)
#define NFS_readdirargs_sz (NFS_fhandle_sz+2)
#define NFS_attrstat_sz (1+NFS_fattr_sz)
#define NFS_diropres_sz (1+NFS_fhandle_sz+NFS_fattr_sz)
#define NFS_readlinkres_sz (2)
#define NFS_readres_sz (1+NFS_fattr_sz+1)
#define NFS_writeres_sz (NFS_attrstat_sz)
#define NFS_stat_sz (1)
#define NFS_readdirres_sz (1)
#define NFS_statfsres_sz (1+NFS_info_sz)
/*
* Common NFS XDR functions as inlines
*/
static inline u32 *
xdr_encode_fhandle(u32 *p, struct nfs_fh *fhandle)
{
memcpy(p, fhandle->data, NFS2_FHSIZE);
return p + XDR_QUADLEN(NFS2_FHSIZE);
}
static inline u32 *
xdr_decode_fhandle(u32 *p, struct nfs_fh *fhandle)
{
/* NFSv2 handles have a fixed length */
fhandle->size = NFS2_FHSIZE;
memcpy(fhandle->data, p, NFS2_FHSIZE);
return p + XDR_QUADLEN(NFS2_FHSIZE);
}
static inline u32*
xdr_encode_time(u32 *p, struct timespec *timep)
{
*p++ = htonl(timep->tv_sec);
/* Convert nanoseconds into microseconds */
*p++ = htonl(timep->tv_nsec ? timep->tv_nsec / 1000 : 0);
return p;
}
static inline u32*
xdr_encode_current_server_time(u32 *p, struct timespec *timep)
{
/*
* Passing the invalid value useconds=1000000 is a
* Sun convention for "set to current server time".
* It's needed to make permissions checks for the
* "touch" program across v2 mounts to Solaris and
* Irix boxes work correctly. See description of
* sattr in section 6.1 of "NFS Illustrated" by
* Brent Callaghan, Addison-Wesley, ISBN 0-201-32750-5
*/
*p++ = htonl(timep->tv_sec);
*p++ = htonl(1000000);
return p;
}
static inline u32*
xdr_decode_time(u32 *p, struct timespec *timep)
{
timep->tv_sec = ntohl(*p++);
/* Convert microseconds into nanoseconds */
timep->tv_nsec = ntohl(*p++) * 1000;
return p;
}
static u32 *
xdr_decode_fattr(u32 *p, struct nfs_fattr *fattr)
{
u32 rdev;
fattr->type = (enum nfs_ftype) ntohl(*p++);
fattr->mode = ntohl(*p++);
fattr->nlink = ntohl(*p++);
fattr->uid = ntohl(*p++);
fattr->gid = ntohl(*p++);
fattr->size = ntohl(*p++);
fattr->du.nfs2.blocksize = ntohl(*p++);
rdev = ntohl(*p++);
fattr->du.nfs2.blocks = ntohl(*p++);
fattr->fsid_u.nfs3 = ntohl(*p++);
fattr->fileid = ntohl(*p++);
p = xdr_decode_time(p, &fattr->atime);
p = xdr_decode_time(p, &fattr->mtime);
p = xdr_decode_time(p, &fattr->ctime);
fattr->valid |= NFS_ATTR_FATTR;
fattr->rdev = new_decode_dev(rdev);
if (fattr->type == NFCHR && rdev == NFS2_FIFO_DEV) {
fattr->type = NFFIFO;
fattr->mode = (fattr->mode & ~S_IFMT) | S_IFIFO;
fattr->rdev = 0;
}
return p;
}
static inline u32 *
xdr_encode_sattr(u32 *p, struct iattr *attr)
{
const u32 not_set = __constant_htonl(0xFFFFFFFF);
*p++ = (attr->ia_valid & ATTR_MODE) ? htonl(attr->ia_mode) : not_set;
*p++ = (attr->ia_valid & ATTR_UID) ? htonl(attr->ia_uid) : not_set;
*p++ = (attr->ia_valid & ATTR_GID) ? htonl(attr->ia_gid) : not_set;
*p++ = (attr->ia_valid & ATTR_SIZE) ? htonl(attr->ia_size) : not_set;
if (attr->ia_valid & ATTR_ATIME_SET) {
p = xdr_encode_time(p, &attr->ia_atime);
} else if (attr->ia_valid & ATTR_ATIME) {
p = xdr_encode_current_server_time(p, &attr->ia_atime);
} else {
*p++ = not_set;
*p++ = not_set;
}
if (attr->ia_valid & ATTR_MTIME_SET) {
p = xdr_encode_time(p, &attr->ia_mtime);
} else if (attr->ia_valid & ATTR_MTIME) {
p = xdr_encode_current_server_time(p, &attr->ia_mtime);
} else {
*p++ = not_set;
*p++ = not_set;
}
return p;
}
/*
* NFS encode functions
*/
/*
* Encode file handle argument
* GETATTR, READLINK, STATFS
*/
static int
nfs_xdr_fhandle(struct rpc_rqst *req, u32 *p, struct nfs_fh *fh)
{
p = xdr_encode_fhandle(p, fh);
req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
return 0;
}
/*
* Encode SETATTR arguments
*/
static int
nfs_xdr_sattrargs(struct rpc_rqst *req, u32 *p, struct nfs_sattrargs *args)
{
p = xdr_encode_fhandle(p, args->fh);
p = xdr_encode_sattr(p, args->sattr);
req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
return 0;
}
/*
* Encode directory ops argument
* LOOKUP, REMOVE, RMDIR
*/
static int
nfs_xdr_diropargs(struct rpc_rqst *req, u32 *p, struct nfs_diropargs *args)
{
p = xdr_encode_fhandle(p, args->fh);
p = xdr_encode_array(p, args->name, args->len);
req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
return 0;
}
/*
* Arguments to a READ call. Since we read data directly into the page
* cache, we also set up the reply iovec here so that iov[1] points
* exactly to the page we want to fetch.
*/
static int
nfs_xdr_readargs(struct rpc_rqst *req, u32 *p, struct nfs_readargs *args)
{
struct rpc_auth *auth = req->rq_task->tk_auth;
unsigned int replen;
u32 offset = (u32)args->offset;
u32 count = args->count;
p = xdr_encode_fhandle(p, args->fh);
*p++ = htonl(offset);
*p++ = htonl(count);
*p++ = htonl(count);
req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
/* Inline the page array */
replen = (RPC_REPHDRSIZE + auth->au_rslack + NFS_readres_sz) << 2;
xdr_inline_pages(&req->rq_rcv_buf, replen,
args->pages, args->pgbase, count);
return 0;
}
/*
* Decode READ reply
*/
static int
nfs_xdr_readres(struct rpc_rqst *req, u32 *p, struct nfs_readres *res)
{
struct kvec *iov = req->rq_rcv_buf.head;
int status, count, recvd, hdrlen;
if ((status = ntohl(*p++)))
return -nfs_stat_to_errno(status);
p = xdr_decode_fattr(p, res->fattr);
count = ntohl(*p++);
res->eof = 0;
hdrlen = (u8 *) p - (u8 *) iov->iov_base;
if (iov->iov_len < hdrlen) {
printk(KERN_WARNING "NFS: READ reply header overflowed:"
"length %d > %Zu\n", hdrlen, iov->iov_len);
return -errno_NFSERR_IO;
} else if (iov->iov_len != hdrlen) {
dprintk("NFS: READ header is short. iovec will be shifted.\n");
xdr_shift_buf(&req->rq_rcv_buf, iov->iov_len - hdrlen);
}
recvd = req->rq_rcv_buf.len - hdrlen;
if (count > recvd) {
printk(KERN_WARNING "NFS: server cheating in read reply: "
"count %d > recvd %d\n", count, recvd);
count = recvd;
}
dprintk("RPC: readres OK count %d\n", count);
if (count < res->count)
res->count = count;
return count;
}
/*
* Write arguments. Splice the buffer to be written into the iovec.
*/
static int
nfs_xdr_writeargs(struct rpc_rqst *req, u32 *p, struct nfs_writeargs *args)
{
struct xdr_buf *sndbuf = &req->rq_snd_buf;
u32 offset = (u32)args->offset;
u32 count = args->count;
p = xdr_encode_fhandle(p, args->fh);
*p++ = htonl(offset);
*p++ = htonl(offset);
*p++ = htonl(count);
*p++ = htonl(count);
sndbuf->len = xdr_adjust_iovec(sndbuf->head, p);
/* Copy the page array */
xdr_encode_pages(sndbuf, args->pages, args->pgbase, count);
return 0;
}
/*
* Encode create arguments
* CREATE, MKDIR
*/
static int
nfs_xdr_createargs(struct rpc_rqst *req, u32 *p, struct nfs_createargs *args)
{
p = xdr_encode_fhandle(p, args->fh);
p = xdr_encode_array(p, args->name, args->len);
p = xdr_encode_sattr(p, args->sattr);
req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
return 0;
}
/*
* Encode RENAME arguments
*/
static int
nfs_xdr_renameargs(struct rpc_rqst *req, u32 *p, struct nfs_renameargs *args)
{
p = xdr_encode_fhandle(p, args->fromfh);
p = xdr_encode_array(p, args->fromname, args->fromlen);
p = xdr_encode_fhandle(p, args->tofh);
p = xdr_encode_array(p, args->toname, args->tolen);
req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
return 0;
}
/*
* Encode LINK arguments
*/
static int
nfs_xdr_linkargs(struct rpc_rqst *req, u32 *p, struct nfs_linkargs *args)
{
p = xdr_encode_fhandle(p, args->fromfh);
p = xdr_encode_fhandle(p, args->tofh);
p = xdr_encode_array(p, args->toname, args->tolen);
req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
return 0;
}
/*
* Encode SYMLINK arguments
*/
static int
nfs_xdr_symlinkargs(struct rpc_rqst *req, u32 *p, struct nfs_symlinkargs *args)
{
p = xdr_encode_fhandle(p, args->fromfh);
p = xdr_encode_array(p, args->fromname, args->fromlen);
p = xdr_encode_array(p, args->topath, args->tolen);
p = xdr_encode_sattr(p, args->sattr);
req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
return 0;
}
/*
* Encode arguments to readdir call
*/
static int
nfs_xdr_readdirargs(struct rpc_rqst *req, u32 *p, struct nfs_readdirargs *args)
{
struct rpc_task *task = req->rq_task;
struct rpc_auth *auth = task->tk_auth;
unsigned int replen;
u32 count = args->count;
p = xdr_encode_fhandle(p, args->fh);
*p++ = htonl(args->cookie);
*p++ = htonl(count); /* see above */
req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
/* Inline the page array */
replen = (RPC_REPHDRSIZE + auth->au_rslack + NFS_readdirres_sz) << 2;
xdr_inline_pages(&req->rq_rcv_buf, replen, args->pages, 0, count);
return 0;
}
/*
* Decode the result of a readdir call.
* We're not really decoding anymore, we just leave the buffer untouched
* and only check that it is syntactically correct.
* The real decoding happens in nfs_decode_entry below, called directly
* from nfs_readdir for each entry.
*/
static int
nfs_xdr_readdirres(struct rpc_rqst *req, u32 *p, void *dummy)
{
struct xdr_buf *rcvbuf = &req->rq_rcv_buf;
struct kvec *iov = rcvbuf->head;
struct page **page;
int hdrlen, recvd;
int status, nr;
unsigned int len, pglen;
u32 *end, *entry, *kaddr;
if ((status = ntohl(*p++)))
return -nfs_stat_to_errno(status);
hdrlen = (u8 *) p - (u8 *) iov->iov_base;
if (iov->iov_len < hdrlen) {
printk(KERN_WARNING "NFS: READDIR reply header overflowed:"
"length %d > %Zu\n", hdrlen, iov->iov_len);
return -errno_NFSERR_IO;
} else if (iov->iov_len != hdrlen) {
dprintk("NFS: READDIR header is short. iovec will be shifted.\n");
xdr_shift_buf(rcvbuf, iov->iov_len - hdrlen);
}
pglen = rcvbuf->page_len;
recvd = rcvbuf->len - hdrlen;
if (pglen > recvd)
pglen = recvd;
page = rcvbuf->pages;
kaddr = p = (u32 *)kmap_atomic(*page, KM_USER0);
end = (u32 *)((char *)p + pglen);
entry = p;
for (nr = 0; *p++; nr++) {
if (p + 2 > end)
goto short_pkt;
p++; /* fileid */
len = ntohl(*p++);
p += XDR_QUADLEN(len) + 1; /* name plus cookie */
if (len > NFS2_MAXNAMLEN) {
printk(KERN_WARNING "NFS: giant filename in readdir (len 0x%x)!\n",
len);
goto err_unmap;
}
if (p + 2 > end)
goto short_pkt;
entry = p;
}
if (!nr && (entry[0] != 0 || entry[1] == 0))
goto short_pkt;
out:
kunmap_atomic(kaddr, KM_USER0);
return nr;
short_pkt:
entry[0] = entry[1] = 0;
/* truncate listing ? */
if (!nr) {
printk(KERN_NOTICE "NFS: readdir reply truncated!\n");
entry[1] = 1;
}
goto out;
err_unmap:
nr = -errno_NFSERR_IO;
goto out;
}
u32 *
nfs_decode_dirent(u32 *p, struct nfs_entry *entry, int plus)
{
if (!*p++) {
if (!*p)
return ERR_PTR(-EAGAIN);
entry->eof = 1;
return ERR_PTR(-EBADCOOKIE);
}
entry->ino = ntohl(*p++);
entry->len = ntohl(*p++);
entry->name = (const char *) p;
p += XDR_QUADLEN(entry->len);
entry->prev_cookie = entry->cookie;
entry->cookie = ntohl(*p++);
entry->eof = !p[0] && p[1];
return p;
}
/*
* NFS XDR decode functions
*/
/*
* Decode simple status reply
*/
static int
nfs_xdr_stat(struct rpc_rqst *req, u32 *p, void *dummy)
{
int status;
if ((status = ntohl(*p++)) != 0)
status = -nfs_stat_to_errno(status);
return status;
}
/*
* Decode attrstat reply
* GETATTR, SETATTR, WRITE
*/
static int
nfs_xdr_attrstat(struct rpc_rqst *req, u32 *p, struct nfs_fattr *fattr)
{
int status;
if ((status = ntohl(*p++)))
return -nfs_stat_to_errno(status);
xdr_decode_fattr(p, fattr);
return 0;
}
/*
* Decode diropres reply
* LOOKUP, CREATE, MKDIR
*/
static int
nfs_xdr_diropres(struct rpc_rqst *req, u32 *p, struct nfs_diropok *res)
{
int status;
if ((status = ntohl(*p++)))
return -nfs_stat_to_errno(status);
p = xdr_decode_fhandle(p, res->fh);
xdr_decode_fattr(p, res->fattr);
return 0;
}
/*
* Encode READLINK args
*/
static int
nfs_xdr_readlinkargs(struct rpc_rqst *req, u32 *p, struct nfs_readlinkargs *args)
{
struct rpc_auth *auth = req->rq_task->tk_auth;
unsigned int replen;
p = xdr_encode_fhandle(p, args->fh);
req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
/* Inline the page array */
replen = (RPC_REPHDRSIZE + auth->au_rslack + NFS_readlinkres_sz) << 2;
xdr_inline_pages(&req->rq_rcv_buf, replen, args->pages, args->pgbase, args->pglen);
return 0;
}
/*
* Decode READLINK reply
*/
static int
nfs_xdr_readlinkres(struct rpc_rqst *req, u32 *p, void *dummy)
{
struct xdr_buf *rcvbuf = &req->rq_rcv_buf;
struct kvec *iov = rcvbuf->head;
int hdrlen, len, recvd;
char *kaddr;
int status;
if ((status = ntohl(*p++)))
return -nfs_stat_to_errno(status);
/* Convert length of symlink */
len = ntohl(*p++);
if (len >= rcvbuf->page_len || len <= 0) {
dprintk(KERN_WARNING "nfs: server returned giant symlink!\n");
return -ENAMETOOLONG;
}
hdrlen = (u8 *) p - (u8 *) iov->iov_base;
if (iov->iov_len < hdrlen) {
printk(KERN_WARNING "NFS: READLINK reply header overflowed:"
"length %d > %Zu\n", hdrlen, iov->iov_len);
return -errno_NFSERR_IO;
} else if (iov->iov_len != hdrlen) {
dprintk("NFS: READLINK header is short. iovec will be shifted.\n");
xdr_shift_buf(rcvbuf, iov->iov_len - hdrlen);
}
recvd = req->rq_rcv_buf.len - hdrlen;
if (recvd < len) {
printk(KERN_WARNING "NFS: server cheating in readlink reply: "
"count %u > recvd %u\n", len, recvd);
return -EIO;
}
/* NULL terminate the string we got */
kaddr = (char *)kmap_atomic(rcvbuf->pages[0], KM_USER0);
kaddr[len+rcvbuf->page_base] = '\0';
kunmap_atomic(kaddr, KM_USER0);
return 0;
}
/*
* Decode WRITE reply
*/
static int
nfs_xdr_writeres(struct rpc_rqst *req, u32 *p, struct nfs_writeres *res)
{
res->verf->committed = NFS_FILE_SYNC;
return nfs_xdr_attrstat(req, p, res->fattr);
}
/*
* Decode STATFS reply
*/
static int
nfs_xdr_statfsres(struct rpc_rqst *req, u32 *p, struct nfs2_fsstat *res)
{
int status;
if ((status = ntohl(*p++)))
return -nfs_stat_to_errno(status);
res->tsize = ntohl(*p++);
res->bsize = ntohl(*p++);
res->blocks = ntohl(*p++);
res->bfree = ntohl(*p++);
res->bavail = ntohl(*p++);
return 0;
}
/*
* We need to translate between nfs status return values and
* the local errno values which may not be the same.
*/
static struct {
int stat;
int errno;
} nfs_errtbl[] = {
{ NFS_OK, 0 },
{ NFSERR_PERM, EPERM },
{ NFSERR_NOENT, ENOENT },
{ NFSERR_IO, errno_NFSERR_IO },
{ NFSERR_NXIO, ENXIO },
/* { NFSERR_EAGAIN, EAGAIN }, */
{ NFSERR_ACCES, EACCES },
{ NFSERR_EXIST, EEXIST },
{ NFSERR_XDEV, EXDEV },
{ NFSERR_NODEV, ENODEV },
{ NFSERR_NOTDIR, ENOTDIR },
{ NFSERR_ISDIR, EISDIR },
{ NFSERR_INVAL, EINVAL },
{ NFSERR_FBIG, EFBIG },
{ NFSERR_NOSPC, ENOSPC },
{ NFSERR_ROFS, EROFS },
{ NFSERR_MLINK, EMLINK },
{ NFSERR_NAMETOOLONG, ENAMETOOLONG },
{ NFSERR_NOTEMPTY, ENOTEMPTY },
{ NFSERR_DQUOT, EDQUOT },
{ NFSERR_STALE, ESTALE },
{ NFSERR_REMOTE, EREMOTE },
#ifdef EWFLUSH
{ NFSERR_WFLUSH, EWFLUSH },
#endif
{ NFSERR_BADHANDLE, EBADHANDLE },
{ NFSERR_NOT_SYNC, ENOTSYNC },
{ NFSERR_BAD_COOKIE, EBADCOOKIE },
{ NFSERR_NOTSUPP, ENOTSUPP },
{ NFSERR_TOOSMALL, ETOOSMALL },
{ NFSERR_SERVERFAULT, ESERVERFAULT },
{ NFSERR_BADTYPE, EBADTYPE },
{ NFSERR_JUKEBOX, EJUKEBOX },
{ -1, EIO }
};
/*
* Convert an NFS error code to a local one.
* This one is used jointly by NFSv2 and NFSv3.
*/
int
nfs_stat_to_errno(int stat)
{
int i;
for (i = 0; nfs_errtbl[i].stat != -1; i++) {
if (nfs_errtbl[i].stat == stat)
return nfs_errtbl[i].errno;
}
printk(KERN_ERR "nfs_stat_to_errno: bad nfs status return value: %d\n", stat);
return nfs_errtbl[i].errno;
}
#ifndef MAX
# define MAX(a, b) (((a) > (b))? (a) : (b))
#endif
#define PROC(proc, argtype, restype, timer) \
[NFSPROC_##proc] = { \
.p_proc = NFSPROC_##proc, \
.p_encode = (kxdrproc_t) nfs_xdr_##argtype, \
.p_decode = (kxdrproc_t) nfs_xdr_##restype, \
.p_bufsiz = MAX(NFS_##argtype##_sz,NFS_##restype##_sz) << 2, \
.p_timer = timer, \
.p_statidx = NFSPROC_##proc, \
.p_name = #proc, \
}
struct rpc_procinfo nfs_procedures[] = {
PROC(GETATTR, fhandle, attrstat, 1),
PROC(SETATTR, sattrargs, attrstat, 0),
PROC(LOOKUP, diropargs, diropres, 2),
PROC(READLINK, readlinkargs, readlinkres, 3),
PROC(READ, readargs, readres, 3),
PROC(WRITE, writeargs, writeres, 4),
PROC(CREATE, createargs, diropres, 0),
PROC(REMOVE, diropargs, stat, 0),
PROC(RENAME, renameargs, stat, 0),
PROC(LINK, linkargs, stat, 0),
PROC(SYMLINK, symlinkargs, stat, 0),
PROC(MKDIR, createargs, diropres, 0),
PROC(RMDIR, diropargs, stat, 0),
PROC(READDIR, readdirargs, readdirres, 3),
PROC(STATFS, fhandle, statfsres, 0),
};
struct rpc_version nfs_version2 = {
.number = 2,
.nrprocs = sizeof(nfs_procedures)/sizeof(nfs_procedures[0]),
.procs = nfs_procedures
};
