nfs4proc.c

linux 内核源代码

/*
 *  fs/nfsd/nfs4proc.c
 *
 *  Server-side procedures for NFSv4.
 *
 *  Copyright (c) 2002 The Regents of the University of Michigan.
 *  All rights reserved.
 *
 *  Kendrick Smith <[e-mail]>
 *  Andy Adamson   <[e-mail]>
 *
 *  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. Neither the name of the University nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED ``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 REGENTS OR CONTRIBUTORS 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 <linux/param.h>
#include <linux/major.h>
#include <linux/slab.h>
#include <linux/file.h>

#include <linux/sunrpc/svc.h>
#include <linux/nfsd/nfsd.h>
#include <linux/nfsd/cache.h>
#include <linux/nfs4.h>
#include <linux/nfsd/state.h>
#include <linux/nfsd/xdr4.h>
#include <linux/nfs4_acl.h>
#include <linux/sunrpc/gss_api.h>

#define NFSDDBG_FACILITY		NFSDDBG_PROC

static inline void
fh_dup2(struct svc_fh *dst, struct svc_fh *src)
{
	fh_put(dst);
	dget(src->fh_dentry);
	if (src->fh_export)
		cache_get(&src->fh_export->h);
	*dst = *src;
}

static __be32
do_open_permission(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nfsd4_open *open, int accmode)
{
	__be32 status;

	if (open->op_truncate &&
		!(open->op_share_access & NFS4_SHARE_ACCESS_WRITE))
		return nfserr_inval;

	if (open->op_share_access & NFS4_SHARE_ACCESS_READ)
		accmode |= MAY_READ;
	if (open->op_share_access & NFS4_SHARE_ACCESS_WRITE)
		accmode |= (MAY_WRITE | MAY_TRUNC);
	if (open->op_share_deny & NFS4_SHARE_DENY_WRITE)
		accmode |= MAY_WRITE;

	status = fh_verify(rqstp, current_fh, S_IFREG, accmode);

	return status;
}

static __be32
do_open_lookup(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nfsd4_open *open)
{
	struct svc_fh resfh;
	__be32 status;
	int created = 0;

	fh_init(&resfh, NFS4_FHSIZE);
	open->op_truncate = 0;

	if (open->op_create) {
		/*
		 * Note: create modes (UNCHECKED,GUARDED...) are the same
		 * in NFSv4 as in v3.
		 */
		status = nfsd_create_v3(rqstp, current_fh, open->op_fname.data,
					open->op_fname.len, &open->op_iattr,
					&resfh, open->op_createmode,
					(u32 *)open->op_verf.data,
					&open->op_truncate, &created);

		/* If we ever decide to use different attrs to store the
		 * verifier in nfsd_create_v3, then we'll need to change this
		 */
		if (open->op_createmode == NFS4_CREATE_EXCLUSIVE && status == 0)
			open->op_bmval[1] |= (FATTR4_WORD1_TIME_ACCESS |
						FATTR4_WORD1_TIME_MODIFY);
	} else {
		status = nfsd_lookup(rqstp, current_fh,
				     open->op_fname.data, open->op_fname.len, &resfh);
		fh_unlock(current_fh);
	}
	if (status)
		goto out;

	set_change_info(&open->op_cinfo, current_fh);

	/* set reply cache */
	fh_dup2(current_fh, &resfh);
	open->op_stateowner->so_replay.rp_openfh_len = resfh.fh_handle.fh_size;
	memcpy(open->op_stateowner->so_replay.rp_openfh,
			&resfh.fh_handle.fh_base, resfh.fh_handle.fh_size);

	if (!created)
		status = do_open_permission(rqstp, current_fh, open, MAY_NOP);

out:
	fh_put(&resfh);
	return status;
}

static __be32
do_open_fhandle(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nfsd4_open *open)
{
	__be32 status;

	/* Only reclaims from previously confirmed clients are valid */
	if ((status = nfs4_check_open_reclaim(&open->op_clientid)))
		return status;

	/* We don't know the target directory, and therefore can not
	* set the change info
	*/

	memset(&open->op_cinfo, 0, sizeof(struct nfsd4_change_info));

	/* set replay cache */
	open->op_stateowner->so_replay.rp_openfh_len = current_fh->fh_handle.fh_size;
	memcpy(open->op_stateowner->so_replay.rp_openfh,
		&current_fh->fh_handle.fh_base,
		current_fh->fh_handle.fh_size);

	open->op_truncate = (open->op_iattr.ia_valid & ATTR_SIZE) &&
		(open->op_iattr.ia_size == 0);

	status = do_open_permission(rqstp, current_fh, open, MAY_OWNER_OVERRIDE);

	return status;
}


static __be32
nfsd4_open(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
	   struct nfsd4_open *open)
{
	__be32 status;
	dprintk("NFSD: nfsd4_open filename %.*s op_stateowner %p\n",
		(int)open->op_fname.len, open->op_fname.data,
		open->op_stateowner);

	/* This check required by spec. */
	if (open->op_create && open->op_claim_type != NFS4_OPEN_CLAIM_NULL)
		return nfserr_inval;

	nfs4_lock_state();

	/* check seqid for replay. set nfs4_owner */
	status = nfsd4_process_open1(open);
	if (status == nfserr_replay_me) {
		struct nfs4_replay *rp = &open->op_stateowner->so_replay;
		fh_put(&cstate->current_fh);
		cstate->current_fh.fh_handle.fh_size = rp->rp_openfh_len;
		memcpy(&cstate->current_fh.fh_handle.fh_base, rp->rp_openfh,
				rp->rp_openfh_len);
		status = fh_verify(rqstp, &cstate->current_fh, 0, MAY_NOP);
		if (status)
			dprintk("nfsd4_open: replay failed"
				" restoring previous filehandle\n");
		else
			status = nfserr_replay_me;
	}
	if (status)
		goto out;

	/* Openowner is now set, so sequence id will get bumped.  Now we need
	 * these checks before we do any creates: */
	status = nfserr_grace;
	if (nfs4_in_grace() && open->op_claim_type != NFS4_OPEN_CLAIM_PREVIOUS)
		goto out;
	status = nfserr_no_grace;
	if (!nfs4_in_grace() && open->op_claim_type == NFS4_OPEN_CLAIM_PREVIOUS)
		goto out;

	switch (open->op_claim_type) {
		case NFS4_OPEN_CLAIM_DELEGATE_CUR:
			status = nfserr_inval;
			if (open->op_create)
				goto out;
			/* fall through */
		case NFS4_OPEN_CLAIM_NULL:
			/*
			 * (1) set CURRENT_FH to the file being opened,
			 * creating it if necessary, (2) set open->op_cinfo,
			 * (3) set open->op_truncate if the file is to be
			 * truncated after opening, (4) do permission checking.
			 */
			status = do_open_lookup(rqstp, &cstate->current_fh,
						open);
			if (status)
				goto out;
			break;
		case NFS4_OPEN_CLAIM_PREVIOUS:
			open->op_stateowner->so_confirmed = 1;
			/*
			 * The CURRENT_FH is already set to the file being
			 * opened.  (1) set open->op_cinfo, (2) set
			 * open->op_truncate if the file is to be truncated
			 * after opening, (3) do permission checking.
			*/
			status = do_open_fhandle(rqstp, &cstate->current_fh,
						 open);
			if (status)
				goto out;
			break;
             	case NFS4_OPEN_CLAIM_DELEGATE_PREV:
			open->op_stateowner->so_confirmed = 1;
			dprintk("NFSD: unsupported OPEN claim type %d\n",
				open->op_claim_type);
			status = nfserr_notsupp;
			goto out;
		default:
			dprintk("NFSD: Invalid OPEN claim type %d\n",
				open->op_claim_type);
			status = nfserr_inval;
			goto out;
	}
	/*
	 * nfsd4_process_open2() does the actual opening of the file.  If
	 * successful, it (1) truncates the file if open->op_truncate was
	 * set, (2) sets open->op_stateid, (3) sets open->op_delegation.
	 */
	status = nfsd4_process_open2(rqstp, &cstate->current_fh, open);
out:
	if (open->op_stateowner) {
		nfs4_get_stateowner(open->op_stateowner);
		cstate->replay_owner = open->op_stateowner;
	}
	nfs4_unlock_state();
	return status;
}

/*
 * filehandle-manipulating ops.
 */
static __be32
nfsd4_getfh(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
	    struct svc_fh **getfh)
{
	if (!cstate->current_fh.fh_dentry)
		return nfserr_nofilehandle;

	*getfh = &cstate->current_fh;
	return nfs_ok;
}

static __be32
nfsd4_putfh(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
	    struct nfsd4_putfh *putfh)
{
	fh_put(&cstate->current_fh);
	cstate->current_fh.fh_handle.fh_size = putfh->pf_fhlen;
	memcpy(&cstate->current_fh.fh_handle.fh_base, putfh->pf_fhval,
	       putfh->pf_fhlen);
	return fh_verify(rqstp, &cstate->current_fh, 0, MAY_NOP);
}

static __be32
nfsd4_putrootfh(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
		void *arg)
{
	__be32 status;

	fh_put(&cstate->current_fh);
	status = exp_pseudoroot(rqstp, &cstate->current_fh);
	return status;
}

static __be32
nfsd4_restorefh(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
		void *arg)
{
	if (!cstate->save_fh.fh_dentry)
		return nfserr_restorefh;

	fh_dup2(&cstate->current_fh, &cstate->save_fh);
	return nfs_ok;
}

static __be32
nfsd4_savefh(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
	     void *arg)
{
	if (!cstate->current_fh.fh_dentry)
		return nfserr_nofilehandle;

	fh_dup2(&cstate->save_fh, &cstate->current_fh);
	return nfs_ok;
}

/*
 * misc nfsv4 ops
 */
static __be32
nfsd4_access(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
	     struct nfsd4_access *access)
{
	if (access->ac_req_access & ~NFS3_ACCESS_FULL)
		return nfserr_inval;

	access->ac_resp_access = access->ac_req_access;
	return nfsd_access(rqstp, &cstate->current_fh, &access->ac_resp_access,
			   &access->ac_supported);
}

static __be32
nfsd4_commit(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
	     struct nfsd4_commit *commit)
{
	__be32 status;

	u32 *p = (u32 *)commit->co_verf.data;
	*p++ = nfssvc_boot.tv_sec;
	*p++ = nfssvc_boot.tv_usec;

	status = nfsd_commit(rqstp, &cstate->current_fh, commit->co_offset,
			     commit->co_count);
	if (status == nfserr_symlink)
		status = nfserr_inval;
	return status;
}

static __be32
nfsd4_create(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
	     struct nfsd4_create *create)
{
	struct svc_fh resfh;
	__be32 status;
	dev_t rdev;

	fh_init(&resfh, NFS4_FHSIZE);

	status = fh_verify(rqstp, &cstate->current_fh, S_IFDIR, MAY_CREATE);
	if (status == nfserr_symlink)
		status = nfserr_notdir;
	if (status)
		return status;

	switch (create->cr_type) {
	case NF4LNK:
		/* ugh! we have to null-terminate the linktext, or
		 * vfs_symlink() will choke.  it is always safe to
		 * null-terminate by brute force, since at worst we
		 * will overwrite the first byte of the create namelen
		 * in the XDR buffer, which has already been extracted
		 * during XDR decode.
		 */
		create->cr_linkname[create->cr_linklen] = 0;

		status = nfsd_symlink(rqstp, &cstate->current_fh,
				      create->cr_name, create->cr_namelen,
				      create->cr_linkname, create->cr_linklen,
				      &resfh, &create->cr_iattr);
		break;

	case NF4BLK:
		rdev = MKDEV(create->cr_specdata1, create->cr_specdata2);
		if (MAJOR(rdev) != create->cr_specdata1 ||
		    MINOR(rdev) != create->cr_specdata2)
			return nfserr_inval;
		status = nfsd_create(rqstp, &cstate->current_fh,
				     create->cr_name, create->cr_namelen,
				     &create->cr_iattr, S_IFBLK, rdev, &resfh);
		break;

	case NF4CHR:
		rdev = MKDEV(create->cr_specdata1, create->cr_specdata2);
		if (MAJOR(rdev) != create->cr_specdata1 ||
		    MINOR(rdev) != create->cr_specdata2)
			return nfserr_inval;
		status = nfsd_create(rqstp, &cstate->current_fh,
				     create->cr_name, create->cr_namelen,
				     &create->cr_iattr,S_IFCHR, rdev, &resfh);
		break;

	case NF4SOCK:
		status = nfsd_create(rqstp, &cstate->current_fh,
				     create->cr_name, create->cr_namelen,
				     &create->cr_iattr, S_IFSOCK, 0, &resfh);
		break;

	case NF4FIFO:
		status = nfsd_create(rqstp, &cstate->current_fh,
				     create->cr_name, create->cr_namelen,
				     &create->cr_iattr, S_IFIFO, 0, &resfh);
		break;

	case NF4DIR:
		create->cr_iattr.ia_valid &= ~ATTR_SIZE;
		status = nfsd_create(rqstp, &cstate->current_fh,
				     create->cr_name, create->cr_namelen,
				     &create->cr_iattr, S_IFDIR, 0, &resfh);
		break;

	default:
		status = nfserr_badtype;
	}

	if (!status) {
		fh_unlock(&cstate->current_fh);
		set_change_info(&create->cr_cinfo, &cstate->current_fh);
		fh_dup2(&cstate->current_fh, &resfh);
	}

	fh_put(&resfh);
	return status;
}

static __be32
nfsd4_getattr(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
	      struct nfsd4_getattr *getattr)
{
	__be32 status;

	status = fh_verify(rqstp, &cstate->current_fh, 0, MAY_NOP);
	if (status)
		return status;

	if (getattr->ga_bmval[1] & NFSD_WRITEONLY_ATTRS_WORD1)
		return nfserr_inval;

	getattr->ga_bmval[0] &= NFSD_SUPPORTED_ATTRS_WORD0;
	getattr->ga_bmval[1] &= NFSD_SUPPORTED_ATTRS_WORD1;

	getattr->ga_fhp = &cstate->current_fh;
	return nfs_ok;
}

static __be32
nfsd4_link(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
	   struct nfsd4_link *link)
{
	__be32 status = nfserr_nofilehandle;

	if (!cstate->save_fh.fh_dentry)
		return status;
	status = nfsd_link(rqstp, &cstate->current_fh,
			   link->li_name, link->li_namelen, &cstate->save_fh);
	if (!status)
		set_change_info(&link->li_cinfo, &cstate->current_fh);
	return status;
}

static __be32
nfsd4_lookupp(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
	      void *arg)
{
	struct svc_fh tmp_fh;
	__be32 ret;

	fh_init(&tmp_fh, NFS4_FHSIZE);
	ret = exp_pseudoroot(rqstp, &tmp_fh);
	if (ret)
		return ret;
	if (tmp_fh.fh_dentry == cstate->current_fh.fh_dentry) {
		fh_put(&tmp_fh);
		return nfserr_noent;
	}
	fh_put(&tmp_fh);
	return nfsd_lookup(rqstp, &cstate->current_fh,
			   "..", 2, &cstate->current_fh);
}

static __be32
nfsd4_lookup(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
	     struct nfsd4_lookup *lookup)
{
	return nfsd_lookup(rqstp, &cstate->current_fh,
			   lookup->lo_name, lookup->lo_len,
			   &cstate->current_fh);
}

static __be32
nfsd4_read(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
	   struct nfsd4_read *read)
{
	__be32 status;

	/* no need to check permission - this will be done in nfsd_read() */

	read->rd_filp = NULL;
	if (read->rd_offset >= OFFSET_MAX)
		return nfserr_inval;

	nfs4_lock_state();
	/* check stateid */
	if ((status = nfs4_preprocess_stateid_op(&cstate->current_fh,
				&read->rd_stateid,
				CHECK_FH | RD_STATE, &read->rd_filp))) {
		dprintk("NFSD: nfsd4_read: couldn't process stateid!\n");
		goto out;
	}
	if (read->rd_filp)
		get_file(read->rd_filp);
	status = nfs_ok;
out:
	nfs4_unlock_state();
	read->rd_rqstp = rqstp;
	read->rd_fhp = &cstate->current_fh;
	return status;
}

static __be32
nfsd4_readdir(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
	      struct nfsd4_readdir *readdir)
{
	u64 cookie = readdir->rd_cookie;
	static const nfs4_verifier zeroverf;

	/* no need to check permission - this will be done in nfsd_readdir() */

	if (readdir->rd_bmval[1] & NFSD_WRITEONLY_ATTRS_WORD1)
		return nfserr_inval;

	readdir->rd_bmval[0] &= NFSD_SUPPORTED_ATTRS_WORD0;
	readdir->rd_bmval[1] &= NFSD_SUPPORTED_ATTRS_WORD1;

	if ((cookie > ~(u32)0) || (cookie == 1) || (cookie == 2) ||
	    (cookie == 0 && memcmp(readdir->rd_verf.data, zeroverf.data, NFS4_VERIFIER_SIZE)))
		return nfserr_bad_cookie;

	readdir->rd_rqstp = rqstp;
	readdir->rd_fhp = &cstate->current_fh;
	return nfs_ok;
}