freebsd-dev/lib/libstand/nfs.c
Jake Burkholder f9751ec2cd Add a hack (kludge?) to avoid trying to access files backed by disk
devices as though they were backed by network devices.
2002-07-07 23:01:36 +00:00

753 lines
15 KiB
C

/* $NetBSD: nfs.c,v 1.2 1998/01/24 12:43:09 drochner Exp $ */
/*-
* Copyright (c) 1993 John Brezak
* 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>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <string.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include "rpcv2.h"
#include "nfsv2.h"
#include "stand.h"
#include "net.h"
#include "netif.h"
#include "rpc.h"
#define NFS_DEBUGxx
/* Define our own NFS attributes without NQNFS stuff. */
struct nfsv2_fattrs {
n_long fa_type;
n_long fa_mode;
n_long fa_nlink;
n_long fa_uid;
n_long fa_gid;
n_long fa_size;
n_long fa_blocksize;
n_long fa_rdev;
n_long fa_blocks;
n_long fa_fsid;
n_long fa_fileid;
struct nfsv2_time fa_atime;
struct nfsv2_time fa_mtime;
struct nfsv2_time fa_ctime;
};
struct nfs_read_args {
u_char fh[NFS_FHSIZE];
n_long off;
n_long len;
n_long xxx; /* XXX what's this for? */
};
/* Data part of nfs rpc reply (also the largest thing we receive) */
#define NFSREAD_SIZE 1024
struct nfs_read_repl {
n_long errno;
struct nfsv2_fattrs fa;
n_long count;
u_char data[NFSREAD_SIZE];
};
#ifndef NFS_NOSYMLINK
struct nfs_readlnk_repl {
n_long errno;
n_long len;
char path[NFS_MAXPATHLEN];
};
#endif
struct nfs_readdir_args {
u_char fh[NFS_FHSIZE];
n_long cookie;
n_long count;
};
struct nfs_readdir_data {
n_long fileid;
n_long len;
char name[0];
};
struct nfs_readdir_off {
n_long cookie;
n_long follows;
};
struct nfs_iodesc {
struct iodesc *iodesc;
off_t off;
u_char fh[NFS_FHSIZE];
struct nfsv2_fattrs fa; /* all in network order */
};
/*
* XXX interactions with tftp? See nfswrapper.c for a confusing
* issue.
*/
int nfs_open(const char *path, struct open_file *f);
static int nfs_close(struct open_file *f);
static int nfs_read(struct open_file *f, void *buf, size_t size, size_t *resid);
static int nfs_write(struct open_file *f, void *buf, size_t size, size_t *resid);
static off_t nfs_seek(struct open_file *f, off_t offset, int where);
static int nfs_stat(struct open_file *f, struct stat *sb);
static int nfs_readdir(struct open_file *f, struct dirent *d);
struct nfs_iodesc nfs_root_node;
struct fs_ops nfs_fsops = {
"nfs",
nfs_open,
nfs_close,
nfs_read,
nfs_write,
nfs_seek,
nfs_stat,
nfs_readdir
};
/*
* Fetch the root file handle (call mount daemon)
* Return zero or error number.
*/
int
nfs_getrootfh(d, path, fhp)
struct iodesc *d;
char *path;
u_char *fhp;
{
int len;
struct args {
n_long len;
char path[FNAME_SIZE];
} *args;
struct repl {
n_long errno;
u_char fh[NFS_FHSIZE];
} *repl;
struct {
n_long h[RPC_HEADER_WORDS];
struct args d;
} sdata;
struct {
n_long h[RPC_HEADER_WORDS];
struct repl d;
} rdata;
size_t cc;
#ifdef NFS_DEBUG
if (debug)
printf("nfs_getrootfh: %s\n", path);
#endif
args = &sdata.d;
repl = &rdata.d;
bzero(args, sizeof(*args));
len = strlen(path);
if (len > sizeof(args->path))
len = sizeof(args->path);
args->len = htonl(len);
bcopy(path, args->path, len);
len = 4 + roundup(len, 4);
cc = rpc_call(d, RPCPROG_MNT, RPCMNT_VER1, RPCMNT_MOUNT,
args, len, repl, sizeof(*repl));
if (cc == -1) {
/* errno was set by rpc_call */
return (errno);
}
if (cc < 4)
return (EBADRPC);
if (repl->errno)
return (ntohl(repl->errno));
bcopy(repl->fh, fhp, sizeof(repl->fh));
return (0);
}
/*
* Lookup a file. Store handle and attributes.
* Return zero or error number.
*/
int
nfs_lookupfh(d, name, newfd)
struct nfs_iodesc *d;
const char *name;
struct nfs_iodesc *newfd;
{
int len, rlen;
struct args {
u_char fh[NFS_FHSIZE];
n_long len;
char name[FNAME_SIZE];
} *args;
struct repl {
n_long errno;
u_char fh[NFS_FHSIZE];
struct nfsv2_fattrs fa;
} *repl;
struct {
n_long h[RPC_HEADER_WORDS];
struct args d;
} sdata;
struct {
n_long h[RPC_HEADER_WORDS];
struct repl d;
} rdata;
ssize_t cc;
#ifdef NFS_DEBUG
if (debug)
printf("lookupfh: called\n");
#endif
args = &sdata.d;
repl = &rdata.d;
bzero(args, sizeof(*args));
bcopy(d->fh, args->fh, sizeof(args->fh));
len = strlen(name);
if (len > sizeof(args->name))
len = sizeof(args->name);
bcopy(name, args->name, len);
args->len = htonl(len);
len = 4 + roundup(len, 4);
len += NFS_FHSIZE;
rlen = sizeof(*repl);
cc = rpc_call(d->iodesc, NFS_PROG, NFS_VER2, NFSPROC_LOOKUP,
args, len, repl, rlen);
if (cc == -1)
return (errno); /* XXX - from rpc_call */
if (cc < 4)
return (EIO);
if (repl->errno) {
/* saerrno.h now matches NFS error numbers. */
return (ntohl(repl->errno));
}
bcopy( repl->fh, &newfd->fh, sizeof(newfd->fh));
bcopy(&repl->fa, &newfd->fa, sizeof(newfd->fa));
return (0);
}
#ifndef NFS_NOSYMLINK
/*
* Get the destination of a symbolic link.
*/
int
nfs_readlink(d, buf)
struct nfs_iodesc *d;
char *buf;
{
struct {
n_long h[RPC_HEADER_WORDS];
u_char fh[NFS_FHSIZE];
} sdata;
struct {
n_long h[RPC_HEADER_WORDS];
struct nfs_readlnk_repl d;
} rdata;
ssize_t cc;
#ifdef NFS_DEBUG
if (debug)
printf("readlink: called\n");
#endif
bcopy(d->fh, sdata.fh, NFS_FHSIZE);
cc = rpc_call(d->iodesc, NFS_PROG, NFS_VER2, NFSPROC_READLINK,
sdata.fh, NFS_FHSIZE,
&rdata.d, sizeof(rdata.d));
if (cc == -1)
return (errno);
if (cc < 4)
return (EIO);
if (rdata.d.errno)
return (ntohl(rdata.d.errno));
rdata.d.len = ntohl(rdata.d.len);
if (rdata.d.len > NFS_MAXPATHLEN)
return (ENAMETOOLONG);
bcopy(rdata.d.path, buf, rdata.d.len);
buf[rdata.d.len] = 0;
return (0);
}
#endif
/*
* Read data from a file.
* Return transfer count or -1 (and set errno)
*/
ssize_t
nfs_readdata(d, off, addr, len)
struct nfs_iodesc *d;
off_t off;
void *addr;
size_t len;
{
struct nfs_read_args *args;
struct nfs_read_repl *repl;
struct {
n_long h[RPC_HEADER_WORDS];
struct nfs_read_args d;
} sdata;
struct {
n_long h[RPC_HEADER_WORDS];
struct nfs_read_repl d;
} rdata;
size_t cc;
long x;
int hlen, rlen;
args = &sdata.d;
repl = &rdata.d;
bcopy(d->fh, args->fh, NFS_FHSIZE);
args->off = htonl((n_long)off);
if (len > NFSREAD_SIZE)
len = NFSREAD_SIZE;
args->len = htonl((n_long)len);
args->xxx = htonl((n_long)0);
hlen = sizeof(*repl) - NFSREAD_SIZE;
cc = rpc_call(d->iodesc, NFS_PROG, NFS_VER2, NFSPROC_READ,
args, sizeof(*args),
repl, sizeof(*repl));
if (cc == -1) {
/* errno was already set by rpc_call */
return (-1);
}
if (cc < hlen) {
errno = EBADRPC;
return (-1);
}
if (repl->errno) {
errno = ntohl(repl->errno);
return (-1);
}
rlen = cc - hlen;
x = ntohl(repl->count);
if (rlen < x) {
printf("nfsread: short packet, %d < %ld\n", rlen, x);
errno = EBADRPC;
return(-1);
}
bcopy(repl->data, addr, x);
return (x);
}
/*
* Open a file.
* return zero or error number
*/
int
nfs_open(upath, f)
const char *upath;
struct open_file *f;
{
struct iodesc *desc;
struct nfs_iodesc *currfd;
#ifndef NFS_NOSYMLINK
struct nfs_iodesc *newfd;
struct nfsv2_fattrs *fa;
char *cp, *ncp;
int c;
char namebuf[NFS_MAXPATHLEN + 1];
char linkbuf[NFS_MAXPATHLEN + 1];
int nlinks = 0;
#endif
int error;
char *path;
#ifdef NFS_DEBUG
if (debug)
printf("nfs_open: %s (rootpath=%s)\n", path, rootpath);
#endif
if (!rootpath[0]) {
printf("no rootpath, no nfs\n");
return (ENXIO);
}
#ifdef __sparc64__
if (strcmp(f->f_dev->dv_name, "net") != 0)
return(EINVAL);
#endif
if (!(desc = socktodesc(*(int *)(f->f_devdata))))
return(EINVAL);
/* Bind to a reserved port. */
desc->myport = htons(--rpc_port);
desc->destip = rootip;
if ((error = nfs_getrootfh(desc, rootpath, nfs_root_node.fh)))
return (error);
nfs_root_node.iodesc = desc;
#ifndef NFS_NOSYMLINK
/* Fake up attributes for the root dir. */
fa = &nfs_root_node.fa;
fa->fa_type = htonl(NFDIR);
fa->fa_mode = htonl(0755);
fa->fa_nlink = htonl(2);
currfd = &nfs_root_node;
newfd = 0;
cp = path = strdup(upath);
if (path == NULL) {
error = ENOMEM;
goto out;
}
while (*cp) {
/*
* Remove extra separators
*/
while (*cp == '/')
cp++;
if (*cp == '\0')
break;
/*
* Check that current node is a directory.
*/
if (currfd->fa.fa_type != htonl(NFDIR)) {
error = ENOTDIR;
goto out;
}
/* allocate file system specific data structure */
newfd = malloc(sizeof(*newfd));
newfd->iodesc = currfd->iodesc;
newfd->off = 0;
/*
* Get next component of path name.
*/
{
int len = 0;
ncp = cp;
while ((c = *cp) != '\0' && c != '/') {
if (++len > NFS_MAXNAMLEN) {
error = ENOENT;
goto out;
}
cp++;
}
*cp = '\0';
}
/* lookup a file handle */
error = nfs_lookupfh(currfd, ncp, newfd);
*cp = c;
if (error)
goto out;
/*
* Check for symbolic link
*/
if (newfd->fa.fa_type == htonl(NFLNK)) {
int link_len, len;
error = nfs_readlink(newfd, linkbuf);
if (error)
goto out;
link_len = strlen(linkbuf);
len = strlen(cp);
if (link_len + len > MAXPATHLEN
|| ++nlinks > MAXSYMLINKS) {
error = ENOENT;
goto out;
}
bcopy(cp, &namebuf[link_len], len + 1);
bcopy(linkbuf, namebuf, link_len);
/*
* If absolute pathname, restart at root.
* If relative pathname, restart at parent directory.
*/
cp = namebuf;
if (*cp == '/') {
if (currfd != &nfs_root_node)
free(currfd);
currfd = &nfs_root_node;
}
free(newfd);
newfd = 0;
continue;
}
if (currfd != &nfs_root_node)
free(currfd);
currfd = newfd;
newfd = 0;
}
error = 0;
out:
if (newfd)
free(newfd);
if (path)
free(path);
#else
/* allocate file system specific data structure */
currfd = malloc(sizeof(*currfd));
currfd->iodesc = desc;
currfd->off = 0;
error = nfs_lookupfh(&nfs_root_node, upath, currfd);
#endif
if (!error) {
f->f_fsdata = (void *)currfd;
return (0);
}
#ifdef NFS_DEBUG
if (debug)
printf("nfs_open: %s lookupfh failed: %s\n",
path, strerror(error));
#endif
#ifndef NFS_NOSYMLINK
if (currfd != &nfs_root_node)
#endif
free(currfd);
return (error);
}
int
nfs_close(f)
struct open_file *f;
{
struct nfs_iodesc *fp = (struct nfs_iodesc *)f->f_fsdata;
#ifdef NFS_DEBUG
if (debug)
printf("nfs_close: fp=0x%lx\n", (u_long)fp);
#endif
if (fp != &nfs_root_node && fp)
free(fp);
f->f_fsdata = (void *)0;
return (0);
}
/*
* read a portion of a file
*/
int
nfs_read(f, buf, size, resid)
struct open_file *f;
void *buf;
size_t size;
size_t *resid; /* out */
{
struct nfs_iodesc *fp = (struct nfs_iodesc *)f->f_fsdata;
ssize_t cc;
char *addr = buf;
#ifdef NFS_DEBUG
if (debug)
printf("nfs_read: size=%lu off=%d\n", (u_long)size,
(int)fp->off);
#endif
while ((int)size > 0) {
twiddle();
cc = nfs_readdata(fp, fp->off, (void *)addr, size);
/* XXX maybe should retry on certain errors */
if (cc == -1) {
#ifdef NFS_DEBUG
if (debug)
printf("nfs_read: read: %s", strerror(errno));
#endif
return (errno); /* XXX - from nfs_readdata */
}
if (cc == 0) {
#ifdef NFS_DEBUG
if (debug)
printf("nfs_read: hit EOF unexpectantly");
#endif
goto ret;
}
fp->off += cc;
addr += cc;
size -= cc;
}
ret:
if (resid)
*resid = size;
return (0);
}
/*
* Not implemented.
*/
int
nfs_write(f, buf, size, resid)
struct open_file *f;
void *buf;
size_t size;
size_t *resid; /* out */
{
return (EROFS);
}
off_t
nfs_seek(f, offset, where)
struct open_file *f;
off_t offset;
int where;
{
struct nfs_iodesc *d = (struct nfs_iodesc *)f->f_fsdata;
n_long size = ntohl(d->fa.fa_size);
switch (where) {
case SEEK_SET:
d->off = offset;
break;
case SEEK_CUR:
d->off += offset;
break;
case SEEK_END:
d->off = size - offset;
break;
default:
return (-1);
}
return (d->off);
}
/* NFNON=0, NFREG=1, NFDIR=2, NFBLK=3, NFCHR=4, NFLNK=5 */
int nfs_stat_types[8] = {
0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK, 0 };
int
nfs_stat(f, sb)
struct open_file *f;
struct stat *sb;
{
struct nfs_iodesc *fp = (struct nfs_iodesc *)f->f_fsdata;
n_long ftype, mode;
ftype = ntohl(fp->fa.fa_type);
mode = ntohl(fp->fa.fa_mode);
mode |= nfs_stat_types[ftype & 7];
sb->st_mode = mode;
sb->st_nlink = ntohl(fp->fa.fa_nlink);
sb->st_uid = ntohl(fp->fa.fa_uid);
sb->st_gid = ntohl(fp->fa.fa_gid);
sb->st_size = ntohl(fp->fa.fa_size);
return (0);
}
static int
nfs_readdir(struct open_file *f, struct dirent *d)
{
struct nfs_iodesc *fp = (struct nfs_iodesc *)f->f_fsdata;
struct nfs_readdir_args *args;
struct nfs_readdir_data *rd;
struct nfs_readdir_off *roff = NULL;
static char *buf;
static n_long cookie = 0;
size_t cc;
n_long eof;
struct {
n_long h[RPC_HEADER_WORDS];
struct nfs_readdir_args d;
} sdata;
static struct {
n_long h[RPC_HEADER_WORDS];
u_char d[NFS_READDIRSIZE];
} rdata;
if (cookie == 0) {
refill:
args = &sdata.d;
bzero(args, sizeof(*args));
bcopy(fp->fh, args->fh, NFS_FHSIZE);
args->cookie = htonl(cookie);
args->count = htonl(NFS_READDIRSIZE);
cc = rpc_call(fp->iodesc, NFS_PROG, NFS_VER2, NFSPROC_READDIR,
args, sizeof(*args),
rdata.d, sizeof(rdata.d));
buf = rdata.d;
roff = (struct nfs_readdir_off *)buf;
if (ntohl(roff->cookie) != 0)
return 1;
}
roff = (struct nfs_readdir_off *)buf;
if (ntohl(roff->follows) == 0) {
eof = ntohl((roff+1)->cookie);
if (eof) {
cookie = 0;
return 1;
}
goto refill;
}
buf += sizeof(struct nfs_readdir_off);
rd = (struct nfs_readdir_data *)buf;
d->d_namlen = ntohl(rd->len);
bcopy(rd->name, d->d_name, d->d_namlen);
d->d_name[d->d_namlen] = '\0';
buf += (sizeof(struct nfs_readdir_data) + roundup(htonl(rd->len),4));
roff = (struct nfs_readdir_off *)buf;
cookie = ntohl(roff->cookie);
return 0;
}