NetBSD/sys/lib/libsa/nfs.c

666 lines
14 KiB
C

/* $NetBSD: nfs.c,v 1.50 2020/01/26 10:13:10 skrll 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.
*/
/*
* XXX Does not currently implement:
* XXX
* XXX LIBSA_NO_FS_CLOSE
* XXX LIBSA_NO_FS_SEEK
* XXX LIBSA_NO_FS_WRITE
* XXX LIBSA_NO_FS_SYMLINK (does this even make sense?)
* XXX LIBSA_FS_SINGLECOMPONENT (does this even make sense?)
*/
#include <sys/param.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <sys/stat.h>
#ifdef _STANDALONE
#include <lib/libkern/libkern.h>
#else
#include <string.h>
#endif
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include "rpcv2.h"
#include "nfsv2.h"
#include "stand.h"
#include "net.h"
#include "nfs.h"
#include "rpc.h"
/* Define our own NFS attributes */
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_iodesc {
struct iodesc *iodesc;
off_t off;
u_char fh[NFS_FHSIZE];
struct nfsv2_fattrs fa; /* all in network order */
};
struct nfs_iodesc nfs_root_node;
int nfs_getrootfh(struct iodesc *, char *, u_char *);
int nfs_lookupfh(struct nfs_iodesc *, const char *, int,
struct nfs_iodesc *);
int nfs_readlink(struct nfs_iodesc *, char *);
ssize_t nfs_readdata(struct nfs_iodesc *, off_t, void *, size_t);
/*
* Fetch the root file handle (call mount daemon)
* On error, return non-zero and set errno.
*/
int
nfs_getrootfh(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;
ssize_t cc;
#ifdef NFS_DEBUG
if (debug)
printf("%s: %s\n", __func__, path);
#endif
args = &sdata.d;
repl = &rdata.d;
(void)memset(args, 0, sizeof(*args));
len = strlen(path);
if ((size_t)len > sizeof(args->path))
len = sizeof(args->path);
args->len = htonl(len);
(void)memcpy(args->path, 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 -1;
}
if (cc < 4) {
errno = EBADRPC;
return -1;
}
if (repl->errno) {
errno = ntohl(repl->errno);
return -1;
}
(void)memcpy(fhp, repl->fh, sizeof(repl->fh));
return 0;
}
/*
* Lookup a file. Store handle and attributes.
* Return zero or error number.
*/
int
nfs_lookupfh(struct nfs_iodesc *d, const char *name, int len,
struct nfs_iodesc *newfd)
{
int 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("%s: called\n", __func__);
#endif
args = &sdata.d;
repl = &rdata.d;
(void)memset(args, 0, sizeof(*args));
(void)memcpy(args->fh, d->fh, sizeof(args->fh));
if ((size_t)len > sizeof(args->name))
len = sizeof(args->name);
(void)memcpy(args->name, 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);
}
(void)memcpy(&newfd->fh, repl->fh, sizeof(newfd->fh));
(void)memcpy(&newfd->fa, &repl->fa, sizeof(newfd->fa));
return 0;
}
#ifndef NFS_NOSYMLINK
/*
* Get the destination of a symbolic link.
*/
int
nfs_readlink(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("%s: called\n", __func__);
#endif
(void)memcpy(sdata.fh, d->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;
(void)memcpy(buf, rdata.d.path, 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(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;
ssize_t cc;
long x;
size_t hlen, rlen;
args = &sdata.d;
repl = &rdata.d;
(void)memcpy(args->fh, d->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 < (ssize_t)hlen) {
errno = EBADRPC;
return -1;
}
if (repl->errno) {
errno = ntohl(repl->errno);
return -1;
}
rlen = cc - hlen;
x = ntohl(repl->count);
if (rlen < (size_t)x) {
printf("%s: short packet, %zu < %ld\n", __func__, rlen, x);
errno = EBADRPC;
return -1;
}
(void)memcpy(addr, repl->data, x);
return x;
}
/*
* nfs_mount - mount this nfs filesystem to a host
* On error, return non-zero and set errno.
*/
int
nfs_mount(int sock, struct in_addr ip, char *path)
{
struct iodesc *desc;
struct nfsv2_fattrs *fa;
if (!(desc = socktodesc(sock))) {
errno = EINVAL;
return -1;
}
/* Bind to a reserved port. */
desc->myport = htons(--rpc_port);
desc->destip = ip;
if (nfs_getrootfh(desc, path, nfs_root_node.fh))
return -1;
nfs_root_node.iodesc = desc;
/* 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);
#ifdef NFS_DEBUG
if (debug)
printf("%s: got fh for %s\n", __func__, path);
#endif
return 0;
}
/*
* Open a file.
* return zero or error number
*/
__compactcall int
nfs_open(const char *path, struct open_file *f)
{
struct nfs_iodesc *newfd, *currfd;
const char *cp;
#ifndef NFS_NOSYMLINK
const char *ncp;
int c;
char namebuf[NFS_MAXPATHLEN + 1];
char linkbuf[NFS_MAXPATHLEN + 1];
int nlinks = 0;
#endif
int error = 0;
#ifdef NFS_DEBUG
if (debug)
printf("%s: %s\n", __func__, path);
#endif
if (nfs_root_node.iodesc == NULL) {
printf("%s: must mount first.\n", __func__);
return ENXIO;
}
currfd = &nfs_root_node;
newfd = 0;
#ifndef NFS_NOSYMLINK
cp = path;
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 = alloc(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++;
}
}
/* lookup a file handle */
error = nfs_lookupfh(currfd, ncp, cp - ncp, newfd);
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;
}
(void)memcpy(&namebuf[link_len], cp, len + 1);
(void)memcpy(namebuf, linkbuf, link_len);
/*
* If absolute pathname, restart at root.
* If relative pathname, restart at parent directory.
*/
cp = namebuf;
if (*cp == '/') {
if (currfd != &nfs_root_node)
dealloc(currfd, sizeof(*currfd));
currfd = &nfs_root_node;
}
dealloc(newfd, sizeof(*newfd));
newfd = 0;
continue;
}
if (currfd != &nfs_root_node)
dealloc(currfd, sizeof(*currfd));
currfd = newfd;
newfd = 0;
}
error = 0;
out:
#else
/* allocate file system specific data structure */
currfd = alloc(sizeof(*currfd));
currfd->iodesc = nfs_root_node.iodesc;
currfd->off = 0;
cp = path;
/*
* Remove extra separators
*/
while (*cp == '/')
cp++;
/* XXX: Check for empty path here? */
error = nfs_lookupfh(&nfs_root_node, cp, strlen(cp), currfd);
#endif
if (!error) {
f->f_fsdata = (void *)currfd;
fsmod = "nfs";
return 0;
}
#ifdef NFS_DEBUG
if (debug)
printf("%s: %s lookupfh failed: %s\n", __func__,
path, strerror(error));
#endif
if (currfd != &nfs_root_node)
dealloc(currfd, sizeof(*currfd));
if (newfd)
dealloc(newfd, sizeof(*newfd));
return error;
}
__compactcall int
nfs_close(struct open_file *f)
{
struct nfs_iodesc *fp = (struct nfs_iodesc *)f->f_fsdata;
#ifdef NFS_DEBUG
if (debug)
printf("%s: fp=%p\n", __func__, fp);
#endif
if (fp)
dealloc(fp, sizeof(struct nfs_iodesc));
f->f_fsdata = (void *)0;
return 0;
}
/*
* read a portion of a file
*/
__compactcall int
nfs_read(struct open_file *f, void *buf, size_t size, size_t *resid)
{
struct nfs_iodesc *fp = (struct nfs_iodesc *)f->f_fsdata;
ssize_t cc;
char *addr = buf;
#ifdef NFS_DEBUG
if (debug)
printf("%s: size=%zu off=%" PRIx64 "\n", __func__, size, fp->off);
#endif
while ((int)size > 0) {
#if !defined(LIBSA_NO_TWIDDLE)
twiddle();
#endif
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("%s: read: %s\n", __func__,
strerror(errno));
#endif
return errno; /* XXX - from nfs_readdata */
}
if (cc == 0) {
#ifdef NFS_DEBUG
if (debug)
printf("%s: hit EOF unexpectedly\n", __func__);
#endif
goto ret;
}
fp->off += cc;
addr += cc;
size -= cc;
}
ret:
if (resid)
*resid = size;
return 0;
}
/*
* Not implemented.
*/
__compactcall int
nfs_write(struct open_file *f, void *buf, size_t size, size_t *resid)
{
return EROFS;
}
__compactcall off_t
nfs_seek(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 */
const int nfs_stat_types[8] = {
0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK, 0 };
__compactcall int
nfs_stat(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;
}
#if defined(LIBSA_ENABLE_LS_OP)
#include "ls.h"
__compactcall void
nfs_ls(struct open_file *f, const char *pattern)
{
lsunsup("nfs");
}
#endif