lib/libstand/nfs.c

	nfs.c revision 199767f8919635c4928607450d9e0abb932109ce
/*  $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 NFSREAD_SIZE 1024

/* Define our own NFS attributes without NQNFS stuff. */
#ifdef OLD_NFSV2
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) */
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 */
};
#else   /* !OLD_NFSV2 */

/* NFSv3 definitions */
#define NFS_V3MAXFHSIZE     64
#define NFS_VER3        3
#define RPCMNT_VER3     3
#define NFSPROCV3_LOOKUP    3
#define NFSPROCV3_READLINK  5
#define NFSPROCV3_READ      6
#define NFSPROCV3_READDIR   16

typedef struct {
    uint32_t val[2];
} n_quad;

struct nfsv3_time {
    uint32_t nfs_sec;
    uint32_t nfs_nsec;
};

struct nfsv3_fattrs {
    uint32_t fa_type;
    uint32_t fa_mode;
    uint32_t fa_nlink;
    uint32_t fa_uid;
    uint32_t fa_gid;
    n_quad fa_size;
    n_quad fa_used;
    n_quad fa_rdev;
    n_quad fa_fsid;
    n_quad fa_fileid;
    struct nfsv3_time fa_atime;
    struct nfsv3_time fa_mtime;
    struct nfsv3_time fa_ctime;
};

/*
 * For NFSv3, the file handle is variable in size, so most fixed sized
 * structures for arguments won't work. For most cases, a structure
 * that starts with any fixed size section is followed by an array
 * that covers the maximum size required.
 */
struct nfsv3_readdir_repl {
    uint32_t errno;
    uint32_t ok;
    struct nfsv3_fattrs fa;
    uint32_t cookiev0;
    uint32_t cookiev1;
};

struct nfsv3_readdir_entry {
    uint32_t follows;
    uint32_t fid0;
    uint32_t fid1;
    uint32_t len;
    uint32_t nameplus[0];
};

struct nfs_iodesc {
    struct iodesc *iodesc;
    off_t off;
    uint32_t fhsize;
    u_char fh[NFS_V3MAXFHSIZE];
    struct nfsv3_fattrs fa; /* all in network order */
    uint64_t cookie;
};
#endif  /* OLD_NFSV2 */

/*
 * 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
};

#ifdef  OLD_NFSV2
/*
 * Fetch the root file handle (call mount daemon)
 * Return zero or error number.
 */
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;
    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(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(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(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(const char *upath, struct open_file *f)
{
    struct iodesc *desc;
    struct nfs_iodesc *currfd;
    char buf[2 * NFS_FHSIZE + 3];
    u_char *fh;
    char *cp;
    int i;
#ifndef NFS_NOSYMLINK
    struct nfs_iodesc *newfd;
    struct nfsv2_fattrs *fa;
    char *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", upath, rootpath);
#endif
    if (!rootpath[0]) {
        printf("no rootpath, no nfs\n");
        return (ENXIO);
    }

    /*
     * This is silly - we should look at dv_type but that value is
     * arch dependant and we can't use it here.
     */
#ifndef __i386__
    if (strcmp(f->f_dev->dv_name, "net") != 0)
        return(EINVAL);
#else
    if (strcmp(f->f_dev->dv_name, "pxe") != 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.fa.fa_type  = htonl(NFDIR);
    nfs_root_node.fa.fa_mode  = htonl(0755);
    nfs_root_node.fa.fa_nlink = htonl(2);
    nfs_root_node.iodesc = desc;

    fh = &nfs_root_node.fh[0];
    buf[0] = 'X';
    cp = &buf[1];
    for (i = 0; i < NFS_FHSIZE; i++, cp += 2)
        sprintf(cp, "%02x", fh[i]);
    sprintf(cp, "X");
    setenv("boot.nfsroot.server", inet_ntoa(rootip), 1);
    setenv("boot.nfsroot.path", rootpath, 1);
    setenv("boot.nfsroot.nfshandle", buf, 1);

    /* Allocate file system specific data structure */
    currfd = malloc(sizeof(*newfd));
    if (currfd == NULL) {
        error = ENOMEM;
        goto out;
    }

#ifndef NFS_NOSYMLINK
    bcopy(&nfs_root_node, currfd, sizeof(*currfd));
    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;

        /*
         * 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 == '/')
                bcopy(&nfs_root_node, currfd, sizeof(*currfd));

            free(newfd);
            newfd = 0;

            continue;
        }

        free(currfd);
        currfd = newfd;
        newfd = 0;
    }

    error = 0;

out:
    free(newfd);
    free(path);
#else
        currfd->iodesc = desc;

        error = nfs_lookupfh(&nfs_root_node, upath, currfd);
#endif
    if (!error) {
        currfd->off = 0;
        f->f_fsdata = (void *)currfd;
        return (0);
    }

#ifdef NFS_DEBUG
    if (debug)
        printf("nfs_open: %s lookupfh failed: %s\n",
            path, strerror(error));
#endif
    free(currfd);

    return (error);
}

int
nfs_close(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)
        free(fp);
    f->f_fsdata = (void *)0;

    return (0);
}

/*
 * read a portion of a file
 */
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("nfs_read: size=%lu off=%d\n", (u_long)size,
               (int)fp->off);
#endif
    while ((int)size > 0) {
        twiddle(16);
        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(struct open_file *f, void *buf, size_t size, size_t *resid)
{
    return (EROFS);
}

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:
        errno = EINVAL;
        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(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 struct nfs_iodesc *pfp = NULL;
    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 (fp != pfp || fp->off != cookie) {
        pfp = NULL;
    refill:
        args = &sdata.d;
        bzero(args, sizeof(*args));

        bcopy(fp->fh, args->fh, NFS_FHSIZE);
        args->cookie = htonl(fp->off);
        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 EIO;
        pfp = fp;
        cookie = fp->off;
    }
    roff = (struct nfs_readdir_off *)buf;

    if (ntohl(roff->follows) == 0) {
        eof = ntohl((roff+1)->cookie);
        if (eof) {
            cookie = 0;
            return ENOENT;
        }
        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;
    fp->off = cookie = ntohl(roff->cookie);
    return 0;
}
#else   /* !OLD_NFSV2 */
/*
 * Fetch the root file handle (call mount daemon)
 * Return zero or error number.
 */
int
nfs_getrootfh(struct iodesc *d, char *path, uint32_t *fhlenp, u_char *fhp)
{
    int len;
    struct args {
        uint32_t len;
        char path[FNAME_SIZE];
    } *args;
    struct repl {
        uint32_t errno;
        uint32_t fhsize;
        u_char fh[NFS_V3MAXFHSIZE];
        uint32_t authcnt;
        uint32_t auth[7];
    } *repl;
    struct {
        uint32_t h[RPC_HEADER_WORDS];
        struct args d;
    } sdata;
    struct {
        uint32_t 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 = sizeof(uint32_t) + roundup(len, sizeof(uint32_t));

    cc = rpc_call(d, RPCPROG_MNT, RPCMNT_VER3, RPCMNT_MOUNT,
        args, len, repl, sizeof(*repl));
    if (cc == -1)
        /* errno was set by rpc_call */
        return (errno);
    if (cc < 2 * sizeof (uint32_t))
        return (EBADRPC);
    if (repl->errno != 0)
        return (ntohl(repl->errno));
    *fhlenp = ntohl(repl->fhsize);
    bcopy(repl->fh, fhp, *fhlenp);
    return (0);
}

/*
 * Lookup a file.  Store handle and attributes.
 * Return zero or error number.
 */
int
nfs_lookupfh(struct nfs_iodesc *d, const char *name, struct nfs_iodesc *newfd)
{
    int len, rlen, pos;
    struct args {
        uint32_t fhsize;
        uint32_t fhplusname[1 +
            (NFS_V3MAXFHSIZE + FNAME_SIZE) / sizeof(uint32_t)];
    } *args;
    struct repl {
        uint32_t errno;
        uint32_t fhsize;
        uint32_t fhplusattr[(NFS_V3MAXFHSIZE +
            2 * (sizeof(uint32_t) +
            sizeof(struct nfsv3_fattrs))) / sizeof(uint32_t)];
    } *repl;
    struct {
        uint32_t h[RPC_HEADER_WORDS];
        struct args d;
    } sdata;
    struct {
        uint32_t 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));
    args->fhsize = htonl(d->fhsize);
    bcopy(d->fh, args->fhplusname, d->fhsize);
    len = strlen(name);
    if (len > FNAME_SIZE)
        len = FNAME_SIZE;
    pos = roundup(d->fhsize, sizeof(uint32_t)) / sizeof(uint32_t);
    args->fhplusname[pos++] = htonl(len);
    bcopy(name, &args->fhplusname[pos], len);
    len = sizeof(uint32_t) + pos * sizeof(uint32_t) +
        roundup(len, sizeof(uint32_t));

    rlen = sizeof(*repl);

    cc = rpc_call(d->iodesc, NFS_PROG, NFS_VER3, NFSPROCV3_LOOKUP,
        args, len, repl, rlen);
    if (cc == -1)
        return (errno);     /* XXX - from rpc_call */
    if (cc < 2 * sizeof(uint32_t))
        return (EIO);
    if (repl->errno != 0)
        /* saerrno.h now matches NFS error numbers. */
        return (ntohl(repl->errno));
    newfd->fhsize = ntohl(repl->fhsize);
    bcopy(repl->fhplusattr, &newfd->fh, newfd->fhsize);
    pos = roundup(newfd->fhsize, sizeof(uint32_t)) / sizeof(uint32_t);
    if (repl->fhplusattr[pos++] == 0)
        return (EIO);
    bcopy(&repl->fhplusattr[pos], &newfd->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 args {
        uint32_t fhsize;
        u_char fh[NFS_V3MAXFHSIZE];
    } *args;
    struct repl {
        uint32_t errno;
        uint32_t ok;
        struct nfsv3_fattrs fa;
        uint32_t len;
        u_char path[NFS_MAXPATHLEN];
    } *repl;
    struct {
        uint32_t h[RPC_HEADER_WORDS];
        struct args d;
    } sdata;
    struct {
        uint32_t h[RPC_HEADER_WORDS];
        struct repl d;
    } rdata;
    ssize_t cc;

#ifdef NFS_DEBUG
    if (debug)
        printf("readlink: called\n");
#endif

    args = &sdata.d;
    repl = &rdata.d;

    bzero(args, sizeof(*args));
    args->fhsize = htonl(d->fhsize);
    bcopy(d->fh, args->fh, d->fhsize);
    cc = rpc_call(d->iodesc, NFS_PROG, NFS_VER3, NFSPROCV3_READLINK,
        args, sizeof(uint32_t) + roundup(d->fhsize, sizeof(uint32_t)),
        repl, sizeof(*repl));
    if (cc == -1)
        return (errno);

    if (cc < 2 * sizeof(uint32_t))
        return (EIO);

    if (repl->errno != 0)
        return (ntohl(repl->errno));

    if (repl->ok == 0)
        return (EIO);

    repl->len = ntohl(repl->len);
    if (repl->len > NFS_MAXPATHLEN)
        return (ENAMETOOLONG);

    bcopy(repl->path, buf, repl->len);
    buf[repl->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 args {
        uint32_t fhsize;
        uint32_t fhoffcnt[NFS_V3MAXFHSIZE / sizeof(uint32_t) + 3];
    } *args;
    struct repl {
        uint32_t errno;
        uint32_t ok;
        struct nfsv3_fattrs fa;
        uint32_t count;
        uint32_t eof;
        uint32_t len;
        u_char data[NFSREAD_SIZE];
    } *repl;
    struct {
        uint32_t h[RPC_HEADER_WORDS];
        struct args d;
    } sdata;
    struct {
        uint32_t h[RPC_HEADER_WORDS];
        struct repl d;
    } rdata;
    size_t cc;
    long x;
    int hlen, rlen, pos;

    args = &sdata.d;
    repl = &rdata.d;

    bzero(args, sizeof(*args));
    args->fhsize = htonl(d->fhsize);
    bcopy(d->fh, args->fhoffcnt, d->fhsize);
    pos = roundup(d->fhsize, sizeof(uint32_t)) / sizeof(uint32_t);
    args->fhoffcnt[pos++] = 0;
    args->fhoffcnt[pos++] = htonl((uint32_t)off);
    if (len > NFSREAD_SIZE)
        len = NFSREAD_SIZE;
    args->fhoffcnt[pos] = htonl((uint32_t)len);
    hlen = sizeof(*repl) - NFSREAD_SIZE;

    cc = rpc_call(d->iodesc, NFS_PROG, NFS_VER3, NFSPROCV3_READ,
        args, 4 * sizeof(uint32_t) + roundup(d->fhsize, sizeof(uint32_t)),
        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 != 0) {
        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(const char *upath, struct open_file *f)
{
    struct iodesc *desc;
    struct nfs_iodesc *currfd;
    char buf[2 * NFS_V3MAXFHSIZE + 3];
    u_char *fh;
    char *cp;
    int i;
#ifndef NFS_NOSYMLINK
    struct nfs_iodesc *newfd;
    struct nfsv3_fattrs *fa;
    char *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", upath, rootpath);
#endif
    if (!rootpath[0]) {
        printf("no rootpath, no nfs\n");
        return (ENXIO);
    }

    /*
     * This is silly - we should look at dv_type but that value is
     * arch dependant and we can't use it here.
     */
#ifndef __i386__
    if (strcmp(f->f_dev->dv_name, "net") != 0)
        return (EINVAL);
#else
    if (strcmp(f->f_dev->dv_name, "pxe") != 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.fhsize,
        nfs_root_node.fh)))
        return (error);
    nfs_root_node.fa.fa_type  = htonl(NFDIR);
    nfs_root_node.fa.fa_mode  = htonl(0755);
    nfs_root_node.fa.fa_nlink = htonl(2);
    nfs_root_node.iodesc = desc;

    fh = &nfs_root_node.fh[0];
    buf[0] = 'X';
    cp = &buf[1];
    for (i = 0; i < nfs_root_node.fhsize; i++, cp += 2)
        sprintf(cp, "%02x", fh[i]);
    sprintf(cp, "X");
    setenv("boot.nfsroot.server", inet_ntoa(rootip), 1);
    setenv("boot.nfsroot.path", rootpath, 1);
    setenv("boot.nfsroot.nfshandle", buf, 1);
    sprintf(buf, "%d", nfs_root_node.fhsize);
    setenv("boot.nfsroot.nfshandlelen", buf, 1);

    /* Allocate file system specific data structure */
    currfd = malloc(sizeof(*newfd));
    if (currfd == NULL) {
        error = ENOMEM;
        goto out;
    }
#ifndef NFS_NOSYMLINK
    bcopy(&nfs_root_node, currfd, sizeof(*currfd));
    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));
        if (newfd == NULL) {
            error = ENOMEM;
            goto out;
        }
        newfd->iodesc = currfd->iodesc;

        /*
         * 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 == '/')
                bcopy(&nfs_root_node, currfd, sizeof(*currfd));

            free(newfd);
            newfd = 0;

            continue;
        }

        free(currfd);
        currfd = newfd;
        newfd = 0;
    }

    error = 0;

out:
    free(newfd);
    free(path);
#else
    currfd->iodesc = desc;

    error = nfs_lookupfh(&nfs_root_node, upath, currfd);
#endif
    if (!error) {
        currfd->off = 0;
        currfd->cookie = 0;
        f->f_fsdata = (void *)currfd;
        return (0);
    }

#ifdef NFS_DEBUG
    if (debug)
        printf("nfs_open: %s lookupfh failed: %s\n",
            path, strerror(error));
#endif
    free(currfd);

    return (error);
}

int
nfs_close(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)
        free(fp);
    f->f_fsdata = (void *)0;

    return (0);
}

/*
 * read a portion of a file
 */
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("nfs_read: size=%lu off=%d\n", (u_long)size,
               (int)fp->off);
#endif
    while ((int)size > 0) {
        twiddle(16);
        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(struct open_file *f, void *buf, size_t size, size_t *resid)
{
    return (EROFS);
}

off_t
nfs_seek(struct open_file *f, off_t offset, int where)
{
    struct nfs_iodesc *d = (struct nfs_iodesc *)f->f_fsdata;
    uint32_t size = ntohl(d->fa.fa_size.val[1]);

    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:
        errno = EINVAL;
        return (-1);
    }

    return (d->off);
}

/* NFNON=0, NFREG=1, NFDIR=2, NFBLK=3, NFCHR=4, NFLNK=5, NFSOCK=6, NFFIFO=7 */
int nfs_stat_types[9] = {
    0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK, S_IFSOCK, S_IFIFO, 0 };

int
nfs_stat(struct open_file *f, struct stat *sb)
{
    struct nfs_iodesc *fp = (struct nfs_iodesc *)f->f_fsdata;
    uint32_t 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.val[1]);

    return (0);
}

static int
nfs_readdir(struct open_file *f, struct dirent *d)
{
    struct nfs_iodesc *fp = (struct nfs_iodesc *)f->f_fsdata;
    struct nfsv3_readdir_repl *repl;
    struct nfsv3_readdir_entry *rent;
    static char *buf;
    static struct nfs_iodesc *pfp = NULL;
    static uint64_t cookie = 0;
    size_t cc;
    int pos;

    struct args {
        uint32_t fhsize;
        uint32_t fhpluscookie[5 + NFS_V3MAXFHSIZE];
    } *args;
    struct {
        uint32_t h[RPC_HEADER_WORDS];
        struct args d;
    } sdata;
    static struct {
        uint32_t h[RPC_HEADER_WORDS];
        u_char d[NFS_READDIRSIZE];
    } rdata;

    if (fp != pfp || fp->off != cookie) {
        pfp = NULL;
    refill:
        args = &sdata.d;
        bzero(args, sizeof(*args));

        args->fhsize = htonl(fp->fhsize);
        bcopy(fp->fh, args->fhpluscookie, fp->fhsize);
        pos = roundup(fp->fhsize, sizeof(uint32_t)) / sizeof(uint32_t);
        args->fhpluscookie[pos++] = htonl(fp->off >> 32);
        args->fhpluscookie[pos++] = htonl(fp->off);
        args->fhpluscookie[pos++] = htonl(fp->cookie >> 32);
        args->fhpluscookie[pos++] = htonl(fp->cookie);
        args->fhpluscookie[pos] = htonl(NFS_READDIRSIZE);

        cc = rpc_call(fp->iodesc, NFS_PROG, NFS_VER3, NFSPROCV3_READDIR,
            args, 6 * sizeof(uint32_t) +
            roundup(fp->fhsize, sizeof(uint32_t)),
            rdata.d, sizeof(rdata.d));
        buf  = rdata.d;
        repl = (struct nfsv3_readdir_repl *)buf;
        if (repl->errno != 0)
            return (ntohl(repl->errno));
        pfp = fp;
        cookie = fp->off;
        fp->cookie = ((uint64_t)ntohl(repl->cookiev0) << 32) |
            ntohl(repl->cookiev1);
        buf += sizeof (struct nfsv3_readdir_repl);
    }
    rent = (struct nfsv3_readdir_entry *)buf;

    if (rent->follows == 0) {
        /* fid0 is actually eof */
        if (rent->fid0 != 0) {
            cookie = 0;
            return (ENOENT);
        }
        goto refill;
    }

    d->d_namlen = ntohl(rent->len);
    bcopy(rent->nameplus, d->d_name, d->d_namlen);
    d->d_name[d->d_namlen] = '\0';

    pos = roundup(d->d_namlen, sizeof(uint32_t)) / sizeof(uint32_t);
    fp->off = cookie = ((uint64_t)ntohl(rent->nameplus[pos]) << 32) |
        ntohl(rent->nameplus[pos + 1]);
    pos += 2;
    buf = (u_char *)&rent->nameplus[pos];
    return (0);
}
#endif  /* OLD_NFSV2 */