xdr.c

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/*
 * linux/fs/lockd/xdr.c
 *
 * XDR support for lockd and the lock client.
 *
 * Copyright (C) 1995, 1996 Olaf Kirch <[email protected]>
 */

#include <linux/types.h>
#include <linux/sched.h>
#include <linux/nfs.h>

#include <linux/sunrpc/xdr.h>
#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/svc.h>
#include <linux/sunrpc/stats.h>
#include <linux/lockd/lockd.h>

#define NLMDBG_FACILITY     NLMDBG_XDR


static inline loff_t
s32_to_loff_t(__s32 offset)
{
    return (loff_t)offset;
}

static inline __s32
loff_t_to_s32(loff_t offset)
{
    __s32 res;
    if (offset >= NLM_OFFSET_MAX)
        res = NLM_OFFSET_MAX;
    else if (offset <= -NLM_OFFSET_MAX)
        res = -NLM_OFFSET_MAX;
    else
        res = offset;
    return res;
}

/*
 * XDR functions for basic NLM types
 */
static __be32 *nlm_decode_cookie(__be32 *p, struct nlm_cookie *c)
{
    unsigned int    len;

    len = ntohl(*p++);
    
    if(len==0)
    {
        c->len=4;
        memset(c->data, 0, 4);  /* hockeypux brain damage */
    }
    else if(len<=NLM_MAXCOOKIELEN)
    {
        c->len=len;
        memcpy(c->data, p, len);
        p+=XDR_QUADLEN(len);
    }
    else 
    {
        dprintk("lockd: bad cookie size %d (only cookies under "
            "%d bytes are supported.)\n",
                len, NLM_MAXCOOKIELEN);
        return NULL;
    }
    return p;
}

static inline __be32 *
nlm_encode_cookie(__be32 *p, struct nlm_cookie *c)
{
    *p++ = htonl(c->len);
    memcpy(p, c->data, c->len);
    p+=XDR_QUADLEN(c->len);
    return p;
}

static __be32 *
nlm_decode_fh(__be32 *p, struct nfs_fh *f)
{
    unsigned int    len;

    if ((len = ntohl(*p++)) != NFS2_FHSIZE) {
        dprintk("lockd: bad fhandle size %d (should be %d)\n",
            len, NFS2_FHSIZE);
        return NULL;
    }
    f->size = NFS2_FHSIZE;
    memset(f->data, 0, sizeof(f->data));
    memcpy(f->data, p, NFS2_FHSIZE);
    return p + XDR_QUADLEN(NFS2_FHSIZE);
}

static inline __be32 *
nlm_encode_fh(__be32 *p, struct nfs_fh *f)
{
    *p++ = htonl(NFS2_FHSIZE);
    memcpy(p, f->data, NFS2_FHSIZE);
    return p + XDR_QUADLEN(NFS2_FHSIZE);
}

/*
 * Encode and decode owner handle
 */
static inline __be32 *
nlm_decode_oh(__be32 *p, struct xdr_netobj *oh)
{
    return xdr_decode_netobj(p, oh);
}

static inline __be32 *
nlm_encode_oh(__be32 *p, struct xdr_netobj *oh)
{
    return xdr_encode_netobj(p, oh);
}

static __be32 *
nlm_decode_lock(__be32 *p, struct nlm_lock *lock)
{
    struct file_lock    *fl = &lock->fl;
    s32         start, len, end;

    if (!(p = xdr_decode_string_inplace(p, &lock->caller,
                        &lock->len,
                        NLM_MAXSTRLEN))
     || !(p = nlm_decode_fh(p, &lock->fh))
     || !(p = nlm_decode_oh(p, &lock->oh)))
        return NULL;
    lock->svid  = ntohl(*p++);

    locks_init_lock(fl);
    fl->fl_owner = current->files;
    fl->fl_pid   = (pid_t)lock->svid;
    fl->fl_flags = FL_POSIX;
    fl->fl_type  = F_RDLCK;     /* as good as anything else */
    start = ntohl(*p++);
    len = ntohl(*p++);
    end = start + len - 1;

    fl->fl_start = s32_to_loff_t(start);

    if (len == 0 || end < 0)
        fl->fl_end = OFFSET_MAX;
    else
        fl->fl_end = s32_to_loff_t(end);
    return p;
}

/*
 * Encode result of a TEST/TEST_MSG call
 */
static __be32 *
nlm_encode_testres(__be32 *p, struct nlm_res *resp)
{
    s32     start, len;

    if (!(p = nlm_encode_cookie(p, &resp->cookie)))
        return NULL;
    *p++ = resp->status;

    if (resp->status == nlm_lck_denied) {
        struct file_lock    *fl = &resp->lock.fl;

        *p++ = (fl->fl_type == F_RDLCK)? xdr_zero : xdr_one;
        *p++ = htonl(resp->lock.svid);

        /* Encode owner handle. */
        if (!(p = xdr_encode_netobj(p, &resp->lock.oh)))
            return NULL;

        start = loff_t_to_s32(fl->fl_start);
        if (fl->fl_end == OFFSET_MAX)
            len = 0;
        else
            len = loff_t_to_s32(fl->fl_end - fl->fl_start + 1);

        *p++ = htonl(start);
        *p++ = htonl(len);
    }

    return p;
}


/*
 * First, the server side XDR functions
 */
int
nlmsvc_decode_testargs(struct svc_rqst *rqstp, __be32 *p, nlm_args *argp)
{
    u32 exclusive;

    if (!(p = nlm_decode_cookie(p, &argp->cookie)))
        return 0;

    exclusive = ntohl(*p++);
    if (!(p = nlm_decode_lock(p, &argp->lock)))
        return 0;
    if (exclusive)
        argp->lock.fl.fl_type = F_WRLCK;

    return xdr_argsize_check(rqstp, p);
}

int
nlmsvc_encode_testres(struct svc_rqst *rqstp, __be32 *p, struct nlm_res *resp)
{
    if (!(p = nlm_encode_testres(p, resp)))
        return 0;
    return xdr_ressize_check(rqstp, p);
}

int
nlmsvc_decode_lockargs(struct svc_rqst *rqstp, __be32 *p, nlm_args *argp)
{
    u32 exclusive;

    if (!(p = nlm_decode_cookie(p, &argp->cookie)))
        return 0;
    argp->block  = ntohl(*p++);
    exclusive    = ntohl(*p++);
    if (!(p = nlm_decode_lock(p, &argp->lock)))
        return 0;
    if (exclusive)
        argp->lock.fl.fl_type = F_WRLCK;
    argp->reclaim = ntohl(*p++);
    argp->state   = ntohl(*p++);
    argp->monitor = 1;      /* monitor client by default */

    return xdr_argsize_check(rqstp, p);
}

int
nlmsvc_decode_cancargs(struct svc_rqst *rqstp, __be32 *p, nlm_args *argp)
{
    u32 exclusive;

    if (!(p = nlm_decode_cookie(p, &argp->cookie)))
        return 0;
    argp->block = ntohl(*p++);
    exclusive = ntohl(*p++);
    if (!(p = nlm_decode_lock(p, &argp->lock)))
        return 0;
    if (exclusive)
        argp->lock.fl.fl_type = F_WRLCK;
    return xdr_argsize_check(rqstp, p);
}

int
nlmsvc_decode_unlockargs(struct svc_rqst *rqstp, __be32 *p, nlm_args *argp)
{
    if (!(p = nlm_decode_cookie(p, &argp->cookie))
     || !(p = nlm_decode_lock(p, &argp->lock)))
        return 0;
    argp->lock.fl.fl_type = F_UNLCK;
    return xdr_argsize_check(rqstp, p);
}

int
nlmsvc_decode_shareargs(struct svc_rqst *rqstp, __be32 *p, nlm_args *argp)
{
    struct nlm_lock *lock = &argp->lock;

    memset(lock, 0, sizeof(*lock));
    locks_init_lock(&lock->fl);
    lock->svid = ~(u32) 0;
    lock->fl.fl_pid = (pid_t)lock->svid;

    if (!(p = nlm_decode_cookie(p, &argp->cookie))
     || !(p = xdr_decode_string_inplace(p, &lock->caller,
                        &lock->len, NLM_MAXSTRLEN))
     || !(p = nlm_decode_fh(p, &lock->fh))
     || !(p = nlm_decode_oh(p, &lock->oh)))
        return 0;
    argp->fsm_mode = ntohl(*p++);
    argp->fsm_access = ntohl(*p++);
    return xdr_argsize_check(rqstp, p);
}

int
nlmsvc_encode_shareres(struct svc_rqst *rqstp, __be32 *p, struct nlm_res *resp)
{
    if (!(p = nlm_encode_cookie(p, &resp->cookie)))
        return 0;
    *p++ = resp->status;
    *p++ = xdr_zero;        /* sequence argument */
    return xdr_ressize_check(rqstp, p);
}

int
nlmsvc_encode_res(struct svc_rqst *rqstp, __be32 *p, struct nlm_res *resp)
{
    if (!(p = nlm_encode_cookie(p, &resp->cookie)))
        return 0;
    *p++ = resp->status;
    return xdr_ressize_check(rqstp, p);
}

int
nlmsvc_decode_notify(struct svc_rqst *rqstp, __be32 *p, struct nlm_args *argp)
{
    struct nlm_lock *lock = &argp->lock;

    if (!(p = xdr_decode_string_inplace(p, &lock->caller,
                        &lock->len, NLM_MAXSTRLEN)))
        return 0;
    argp->state = ntohl(*p++);
    return xdr_argsize_check(rqstp, p);
}

int
nlmsvc_decode_reboot(struct svc_rqst *rqstp, __be32 *p, struct nlm_reboot *argp)
{
    if (!(p = xdr_decode_string_inplace(p, &argp->mon, &argp->len, SM_MAXSTRLEN)))
        return 0;
    argp->state = ntohl(*p++);
    memcpy(&argp->priv.data, p, sizeof(argp->priv.data));
    p += XDR_QUADLEN(SM_PRIV_SIZE);
    return xdr_argsize_check(rqstp, p);
}

int
nlmsvc_decode_res(struct svc_rqst *rqstp, __be32 *p, struct nlm_res *resp)
{
    if (!(p = nlm_decode_cookie(p, &resp->cookie)))
        return 0;
    resp->status = *p++;
    return xdr_argsize_check(rqstp, p);
}

int
nlmsvc_decode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
{
    return xdr_argsize_check(rqstp, p);
}

int
nlmsvc_encode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
{
    return xdr_ressize_check(rqstp, p);
}