[linux-block.git] / fs / nfs / mount_clnt.c

// SPDX-License-Identifier: GPL-2.0
/*
 * In-kernel MOUNT protocol client
 *
 * Copyright (C) 1997, Olaf Kirch <okir@monad.swb.de>
 */

#include <linux/types.h>
#include <linux/socket.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/uio.h>
#include <linux/net.h>
#include <linux/in.h>
#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/sched.h>
#include <linux/nfs_fs.h>
#include "internal.h"

#define NFSDBG_FACILITY	NFSDBG_MOUNT

/*
 * Defined by RFC 1094, section A.3; and RFC 1813, section 5.1.4
 */
#define MNTPATHLEN		(1024)

/*
 * XDR data type sizes
 */
#define encode_dirpath_sz	(1 + XDR_QUADLEN(MNTPATHLEN))
#define MNT_status_sz		(1)
#define MNT_fhandle_sz		XDR_QUADLEN(NFS2_FHSIZE)
#define MNT_fhandlev3_sz	XDR_QUADLEN(NFS3_FHSIZE)
#define MNT_authflav3_sz	(1 + NFS_MAX_SECFLAVORS)

/*
 * XDR argument and result sizes
 */
#define MNT_enc_dirpath_sz	encode_dirpath_sz
#define MNT_dec_mountres_sz	(MNT_status_sz + MNT_fhandle_sz)
#define MNT_dec_mountres3_sz	(MNT_status_sz + MNT_fhandlev3_sz + \
				 MNT_authflav3_sz)

/*
 * Defined by RFC 1094, section A.5
 */
enum {
	MOUNTPROC_NULL		= 0,
	MOUNTPROC_MNT		= 1,
	MOUNTPROC_DUMP		= 2,
	MOUNTPROC_UMNT		= 3,
	MOUNTPROC_UMNTALL	= 4,
	MOUNTPROC_EXPORT	= 5,
};

/*
 * Defined by RFC 1813, section 5.2
 */
enum {
	MOUNTPROC3_NULL		= 0,
	MOUNTPROC3_MNT		= 1,
	MOUNTPROC3_DUMP		= 2,
	MOUNTPROC3_UMNT		= 3,
	MOUNTPROC3_UMNTALL	= 4,
	MOUNTPROC3_EXPORT	= 5,
};

static const struct rpc_program mnt_program;

/*
 * Defined by OpenGroup XNFS Version 3W, chapter 8
 */
enum mountstat {
	MNT_OK			= 0,
	MNT_EPERM		= 1,
	MNT_ENOENT		= 2,
	MNT_EACCES		= 13,
	MNT_EINVAL		= 22,
};

static struct {
	u32 status;
	int errno;
} mnt_errtbl[] = {
	{ .status = MNT_OK,			.errno = 0,		},
	{ .status = MNT_EPERM,			.errno = -EPERM,	},
	{ .status = MNT_ENOENT,			.errno = -ENOENT,	},
	{ .status = MNT_EACCES,			.errno = -EACCES,	},
	{ .status = MNT_EINVAL,			.errno = -EINVAL,	},
};

/*
 * Defined by RFC 1813, section 5.1.5
 */
enum mountstat3 {
	MNT3_OK			= 0,		/* no error */
	MNT3ERR_PERM		= 1,		/* Not owner */
	MNT3ERR_NOENT		= 2,		/* No such file or directory */
	MNT3ERR_IO		= 5,		/* I/O error */
	MNT3ERR_ACCES		= 13,		/* Permission denied */
	MNT3ERR_NOTDIR		= 20,		/* Not a directory */
	MNT3ERR_INVAL		= 22,		/* Invalid argument */
	MNT3ERR_NAMETOOLONG	= 63,		/* Filename too long */
	MNT3ERR_NOTSUPP		= 10004,	/* Operation not supported */
	MNT3ERR_SERVERFAULT	= 10006,	/* A failure on the server */
};

static struct {
	u32 status;
	int errno;
} mnt3_errtbl[] = {
	{ .status = MNT3_OK,			.errno = 0,		},
	{ .status = MNT3ERR_PERM,		.errno = -EPERM,	},
	{ .status = MNT3ERR_NOENT,		.errno = -ENOENT,	},
	{ .status = MNT3ERR_IO,			.errno = -EIO,		},
	{ .status = MNT3ERR_ACCES,		.errno = -EACCES,	},
	{ .status = MNT3ERR_NOTDIR,		.errno = -ENOTDIR,	},
	{ .status = MNT3ERR_INVAL,		.errno = -EINVAL,	},
	{ .status = MNT3ERR_NAMETOOLONG,	.errno = -ENAMETOOLONG,	},
	{ .status = MNT3ERR_NOTSUPP,		.errno = -ENOTSUPP,	},
	{ .status = MNT3ERR_SERVERFAULT,	.errno = -EREMOTEIO,	},
};

struct mountres {
	int errno;
	struct nfs_fh *fh;
	unsigned int *auth_count;
	rpc_authflavor_t *auth_flavors;
};

struct mnt_fhstatus {
	u32 status;
	struct nfs_fh *fh;
};

/**
 * nfs_mount - Obtain an NFS file handle for the given host and path
 * @info: pointer to mount request arguments
 * @timeo: deciseconds the mount waits for a response before it retries
 * @retrans: number of times the mount retries a request
 *
 * Uses timeout parameters specified by caller. On successful return, the
 * auth_flavs list and auth_flav_len will be populated with the list from the
 * server or a faked-up list if the server didn't provide one.
 */
int nfs_mount(struct nfs_mount_request *info, int timeo, int retrans)
{
	struct rpc_timeout mnt_timeout;
	struct mountres	result = {
		.fh		= info->fh,
		.auth_count	= info->auth_flav_len,
		.auth_flavors	= info->auth_flavs,
	};
	struct rpc_message msg	= {
		.rpc_argp	= info->dirpath,
		.rpc_resp	= &result,
	};
	struct rpc_create_args args = {
		.net		= info->net,
		.protocol	= info->protocol,
		.address	= info->sap,
		.addrsize	= info->salen,
		.timeout	= &mnt_timeout,
		.servername	= info->hostname,
		.program	= &mnt_program,
		.version	= info->version,
		.authflavor	= RPC_AUTH_UNIX,
		.cred		= current_cred(),
	};
	struct rpc_clnt		*mnt_clnt;
	int			status;

	dprintk("NFS: sending MNT request for %s:%s\n",
		(info->hostname ? info->hostname : "server"),
			info->dirpath);

	if (strlen(info->dirpath) > MNTPATHLEN)
		return -ENAMETOOLONG;

	if (info->noresvport)
		args.flags |= RPC_CLNT_CREATE_NONPRIVPORT;

	nfs_init_timeout_values(&mnt_timeout, info->protocol, timeo, retrans);
	mnt_clnt = rpc_create(&args);
	if (IS_ERR(mnt_clnt))
		goto out_clnt_err;

	if (info->version == NFS_MNT3_VERSION)
		msg.rpc_proc = &mnt_clnt->cl_procinfo[MOUNTPROC3_MNT];
	else
		msg.rpc_proc = &mnt_clnt->cl_procinfo[MOUNTPROC_MNT];

	status = rpc_call_sync(mnt_clnt, &msg, RPC_TASK_SOFT|RPC_TASK_TIMEOUT);
	rpc_shutdown_client(mnt_clnt);

	if (status < 0)
		goto out_call_err;
	if (result.errno != 0)
		goto out_mnt_err;

	dprintk("NFS: MNT request succeeded\n");
	status = 0;

	/*
	 * If the server didn't provide a flavor list, allow the
	 * client to try any flavor.
	 */
	if (info->version != NFS_MNT3_VERSION || *info->auth_flav_len == 0) {
		dprintk("NFS: Faking up auth_flavs list\n");
		info->auth_flavs[0] = RPC_AUTH_NULL;
		*info->auth_flav_len = 1;
	}
out:
	return status;

out_clnt_err:
	status = PTR_ERR(mnt_clnt);
	dprintk("NFS: failed to create MNT RPC client, status=%d\n", status);
	goto out;

out_call_err:
	dprintk("NFS: MNT request failed, status=%d\n", status);
	goto out;

out_mnt_err:
	dprintk("NFS: MNT server returned result %d\n", result.errno);
	status = result.errno;
	goto out;
}

/**
 * nfs_umount - Notify a server that we have unmounted this export
 * @info: pointer to umount request arguments
 *
 * MOUNTPROC_UMNT is advisory, so we set a short timeout, and always
 * use UDP.
 */
void nfs_umount(const struct nfs_mount_request *info)
{
	static const struct rpc_timeout nfs_umnt_timeout = {
		.to_initval = 1 * HZ,
		.to_maxval = 3 * HZ,
		.to_retries = 2,
	};
	struct rpc_create_args args = {
		.net		= info->net,
		.protocol	= IPPROTO_UDP,
		.address	= info->sap,
		.addrsize	= info->salen,
		.timeout	= &nfs_umnt_timeout,
		.servername	= info->hostname,
		.program	= &mnt_program,
		.version	= info->version,
		.authflavor	= RPC_AUTH_UNIX,
		.flags		= RPC_CLNT_CREATE_NOPING,
		.cred		= current_cred(),
	};
	struct rpc_message msg	= {
		.rpc_argp	= info->dirpath,
	};
	struct rpc_clnt *clnt;
	int status;

	if (strlen(info->dirpath) > MNTPATHLEN)
		return;

	if (info->noresvport)
		args.flags |= RPC_CLNT_CREATE_NONPRIVPORT;

	clnt = rpc_create(&args);
	if (IS_ERR(clnt))
		goto out_clnt_err;

	dprintk("NFS: sending UMNT request for %s:%s\n",
		(info->hostname ? info->hostname : "server"), info->dirpath);

	if (info->version == NFS_MNT3_VERSION)
		msg.rpc_proc = &clnt->cl_procinfo[MOUNTPROC3_UMNT];
	else
		msg.rpc_proc = &clnt->cl_procinfo[MOUNTPROC_UMNT];

	status = rpc_call_sync(clnt, &msg, 0);
	rpc_shutdown_client(clnt);

	if (unlikely(status < 0))
		goto out_call_err;

	return;

out_clnt_err:
	dprintk("NFS: failed to create UMNT RPC client, status=%ld\n",
			PTR_ERR(clnt));
	return;

out_call_err:
	dprintk("NFS: UMNT request failed, status=%d\n", status);
}

/*
 * XDR encode/decode functions for MOUNT
 */

static void encode_mntdirpath(struct xdr_stream *xdr, const char *pathname)
{
	const u32 pathname_len = strlen(pathname);
	__be32 *p;

	p = xdr_reserve_space(xdr, 4 + pathname_len);
	xdr_encode_opaque(p, pathname, pathname_len);
}

static void mnt_xdr_enc_dirpath(struct rpc_rqst *req, struct xdr_stream *xdr,
				const void *dirpath)
{
	encode_mntdirpath(xdr, dirpath);
}

/*
 * RFC 1094: "A non-zero status indicates some sort of error.  In this
 * case, the status is a UNIX error number."  This can be problematic
 * if the server and client use different errno values for the same
 * error.
 *
 * However, the OpenGroup XNFS spec provides a simple mapping that is
 * independent of local errno values on the server and the client.
 */
static int decode_status(struct xdr_stream *xdr, struct mountres *res)
{
	unsigned int i;
	u32 status;
	__be32 *p;

	p = xdr_inline_decode(xdr, 4);
	if (unlikely(p == NULL))
		return -EIO;
	status = be32_to_cpup(p);

	for (i = 0; i < ARRAY_SIZE(mnt_errtbl); i++) {
		if (mnt_errtbl[i].status == status) {
			res->errno = mnt_errtbl[i].errno;
			return 0;
		}
	}

	dprintk("NFS: unrecognized MNT status code: %u\n", status);
	res->errno = -EACCES;
	return 0;
}

static int decode_fhandle(struct xdr_stream *xdr, struct mountres *res)
{
	struct nfs_fh *fh = res->fh;
	__be32 *p;

	p = xdr_inline_decode(xdr, NFS2_FHSIZE);
	if (unlikely(p == NULL))
		return -EIO;

	fh->size = NFS2_FHSIZE;
	memcpy(fh->data, p, NFS2_FHSIZE);
	return 0;
}

static int mnt_xdr_dec_mountres(struct rpc_rqst *req,
				struct xdr_stream *xdr,
				void *data)
{
	struct mountres *res = data;
	int status;

	status = decode_status(xdr, res);
	if (unlikely(status != 0 || res->errno != 0))
		return status;
	return decode_fhandle(xdr, res);
}

static int decode_fhs_status(struct xdr_stream *xdr, struct mountres *res)
{
	unsigned int i;
	u32 status;
	__be32 *p;

	p = xdr_inline_decode(xdr, 4);
	if (unlikely(p == NULL))
		return -EIO;
	status = be32_to_cpup(p);

	for (i = 0; i < ARRAY_SIZE(mnt3_errtbl); i++) {
		if (mnt3_errtbl[i].status == status) {
			res->errno = mnt3_errtbl[i].errno;
			return 0;
		}
	}

	dprintk("NFS: unrecognized MNT3 status code: %u\n", status);
	res->errno = -EACCES;
	return 0;
}

static int decode_fhandle3(struct xdr_stream *xdr, struct mountres *res)
{
	struct nfs_fh *fh = res->fh;
	u32 size;
	__be32 *p;

	p = xdr_inline_decode(xdr, 4);
	if (unlikely(p == NULL))
		return -EIO;

	size = be32_to_cpup(p);
	if (size > NFS3_FHSIZE || size == 0)
		return -EIO;

	p = xdr_inline_decode(xdr, size);
	if (unlikely(p == NULL))
		return -EIO;

	fh->size = size;
	memcpy(fh->data, p, size);
	return 0;
}

static int decode_auth_flavors(struct xdr_stream *xdr, struct mountres *res)
{
	rpc_authflavor_t *flavors = res->auth_flavors;
	unsigned int *count = res->auth_count;
	u32 entries, i;
	__be32 *p;

	if (*count == 0)
		return 0;

	p = xdr_inline_decode(xdr, 4);
	if (unlikely(p == NULL))
		return -EIO;
	entries = be32_to_cpup(p);
	dprintk("NFS: received %u auth flavors\n", entries);
	if (entries > NFS_MAX_SECFLAVORS)
		entries = NFS_MAX_SECFLAVORS;

	p = xdr_inline_decode(xdr, 4 * entries);
	if (unlikely(p == NULL))
		return -EIO;

	if (entries > *count)
		entries = *count;

	for (i = 0; i < entries; i++) {
		flavors[i] = be32_to_cpup(p++);
		dprintk("NFS:   auth flavor[%u]: %d\n", i, flavors[i]);
	}
	*count = i;

	return 0;
}

static int mnt_xdr_dec_mountres3(struct rpc_rqst *req,
				 struct xdr_stream *xdr,
				 void *data)
{
	struct mountres *res = data;
	int status;

	status = decode_fhs_status(xdr, res);
	if (unlikely(status != 0 || res->errno != 0))
		return status;
	status = decode_fhandle3(xdr, res);
	if (unlikely(status != 0)) {
		res->errno = -EBADHANDLE;
		return 0;
	}
	return decode_auth_flavors(xdr, res);
}

static const struct rpc_procinfo mnt_procedures[] = {
	[MOUNTPROC_MNT] = {
		.p_proc		= MOUNTPROC_MNT,
		.p_encode	= mnt_xdr_enc_dirpath,
		.p_decode	= mnt_xdr_dec_mountres,
		.p_arglen	= MNT_enc_dirpath_sz,
		.p_replen	= MNT_dec_mountres_sz,
		.p_statidx	= MOUNTPROC_MNT,
		.p_name		= "MOUNT",
	},
	[MOUNTPROC_UMNT] = {
		.p_proc		= MOUNTPROC_UMNT,
		.p_encode	= mnt_xdr_enc_dirpath,
		.p_arglen	= MNT_enc_dirpath_sz,
		.p_statidx	= MOUNTPROC_UMNT,
		.p_name		= "UMOUNT",
	},
};

static const struct rpc_procinfo mnt3_procedures[] = {
	[MOUNTPROC3_MNT] = {
		.p_proc		= MOUNTPROC3_MNT,
		.p_encode	= mnt_xdr_enc_dirpath,
		.p_decode	= mnt_xdr_dec_mountres3,
		.p_arglen	= MNT_enc_dirpath_sz,
		.p_replen	= MNT_dec_mountres3_sz,
		.p_statidx	= MOUNTPROC3_MNT,
		.p_name		= "MOUNT",
	},
	[MOUNTPROC3_UMNT] = {
		.p_proc		= MOUNTPROC3_UMNT,
		.p_encode	= mnt_xdr_enc_dirpath,
		.p_arglen	= MNT_enc_dirpath_sz,
		.p_statidx	= MOUNTPROC3_UMNT,
		.p_name		= "UMOUNT",
	},
};

static unsigned int mnt_counts[ARRAY_SIZE(mnt_procedures)];
static const struct rpc_version mnt_version1 = {
	.number		= 1,
	.nrprocs	= ARRAY_SIZE(mnt_procedures),
	.procs		= mnt_procedures,
	.counts		= mnt_counts,
};

static unsigned int mnt3_counts[ARRAY_SIZE(mnt3_procedures)];
static const struct rpc_version mnt_version3 = {
	.number		= 3,
	.nrprocs	= ARRAY_SIZE(mnt3_procedures),
	.procs		= mnt3_procedures,
	.counts		= mnt3_counts,
};

static const struct rpc_version *mnt_version[] = {
	NULL,
	&mnt_version1,
	NULL,
	&mnt_version3,
};

static struct rpc_stat mnt_stats;

static const struct rpc_program mnt_program = {
	.name		= "mount",
	.number		= NFS_MNT_PROGRAM,
	.nrvers		= ARRAY_SIZE(mnt_version),
	.version	= mnt_version,
	.stats		= &mnt_stats,
};
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
1da177e4	2	/*
19207231	3	* In-kernel MOUNT protocol client
1da177e4 LT	4	*
	5	* Copyright (C) 1997, Olaf Kirch <okir@monad.swb.de>
	6	*/
	7
	8	#include <linux/types.h>
	9	#include <linux/socket.h>
	10	#include <linux/kernel.h>
	11	#include <linux/errno.h>
	12	#include <linux/uio.h>
	13	#include <linux/net.h>
	14	#include <linux/in.h>
	15	#include <linux/sunrpc/clnt.h>
1da177e4 LT	16	#include <linux/sunrpc/sched.h>
1da177e4 LT	17	#include <linux/nfs_fs.h>
8491945f	18	#include "internal.h"
1da177e4	19
39de493e	20	#define NFSDBG_FACILITY NFSDBG_MOUNT
1da177e4	21
29a1bd6b CL	22	/*
	23	* Defined by RFC 1094, section A.3; and RFC 1813, section 5.1.4
	24	*/
	25	#define MNTPATHLEN (1024)
	26
	27	/*
	28	* XDR data type sizes
	29	*/
	30	#define encode_dirpath_sz (1 + XDR_QUADLEN(MNTPATHLEN))
fb125295	31	#define MNT_status_sz (1)
4fdcd996	32	#define MNT_fhandle_sz XDR_QUADLEN(NFS2_FHSIZE)
8eed292b	33	#define MNT_fhandlev3_sz XDR_QUADLEN(NFS3_FHSIZE)
a14017db	34	#define MNT_authflav3_sz (1 + NFS_MAX_SECFLAVORS)
29a1bd6b CL	35
	36	/*
	37	* XDR argument and result sizes
	38	*/
	39	#define MNT_enc_dirpath_sz encode_dirpath_sz
8e02f6b9	40	#define MNT_dec_mountres_sz (MNT_status_sz + MNT_fhandle_sz)
8eed292b	41	#define MNT_dec_mountres3_sz (MNT_status_sz + MNT_fhandlev3_sz + \
8e02f6b9	42	MNT_authflav3_sz)
29a1bd6b	43
2ad78097 CL	44	/*
	45	* Defined by RFC 1094, section A.5
	46	*/
	47	enum {
	48	MOUNTPROC_NULL = 0,
	49	MOUNTPROC_MNT = 1,
	50	MOUNTPROC_DUMP = 2,
	51	MOUNTPROC_UMNT = 3,
	52	MOUNTPROC_UMNTALL = 4,
	53	MOUNTPROC_EXPORT = 5,
	54	};
	55
	56	/*
	57	* Defined by RFC 1813, section 5.2
	58	*/
	59	enum {
	60	MOUNTPROC3_NULL = 0,
	61	MOUNTPROC3_MNT = 1,
	62	MOUNTPROC3_DUMP = 2,
	63	MOUNTPROC3_UMNT = 3,
	64	MOUNTPROC3_UMNTALL = 4,
	65	MOUNTPROC3_EXPORT = 5,
	66	};
	67
a613fa16	68	static const struct rpc_program mnt_program;
1da177e4	69
fb125295 CL	70	/*
	71	* Defined by OpenGroup XNFS Version 3W, chapter 8
	72	*/
	73	enum mountstat {
	74	MNT_OK = 0,
	75	MNT_EPERM = 1,
	76	MNT_ENOENT = 2,
	77	MNT_EACCES = 13,
	78	MNT_EINVAL = 22,
	79	};
	80
	81	static struct {
	82	u32 status;
	83	int errno;
	84	} mnt_errtbl[] = {
	85	{ .status = MNT_OK, .errno = 0, },
	86	{ .status = MNT_EPERM, .errno = -EPERM, },
	87	{ .status = MNT_ENOENT, .errno = -ENOENT, },
	88	{ .status = MNT_EACCES, .errno = -EACCES, },
	89	{ .status = MNT_EINVAL, .errno = -EINVAL, },
	90	};
	91
	92	/*
	93	* Defined by RFC 1813, section 5.1.5
	94	*/
	95	enum mountstat3 {
	96	MNT3_OK = 0, /* no error */
	97	MNT3ERR_PERM = 1, /* Not owner */
	98	MNT3ERR_NOENT = 2, /* No such file or directory */
	99	MNT3ERR_IO = 5, /* I/O error */
	100	MNT3ERR_ACCES = 13, /* Permission denied */
	101	MNT3ERR_NOTDIR = 20, /* Not a directory */
	102	MNT3ERR_INVAL = 22, /* Invalid argument */
	103	MNT3ERR_NAMETOOLONG = 63, /* Filename too long */
	104	MNT3ERR_NOTSUPP = 10004, /* Operation not supported */
	105	MNT3ERR_SERVERFAULT = 10006, /* A failure on the server */
	106	};
	107
	108	static struct {
	109	u32 status;
	110	int errno;
	111	} mnt3_errtbl[] = {
	112	{ .status = MNT3_OK, .errno = 0, },
	113	{ .status = MNT3ERR_PERM, .errno = -EPERM, },
	114	{ .status = MNT3ERR_NOENT, .errno = -ENOENT, },
	115	{ .status = MNT3ERR_IO, .errno = -EIO, },
	116	{ .status = MNT3ERR_ACCES, .errno = -EACCES, },
	117	{ .status = MNT3ERR_NOTDIR, .errno = -ENOTDIR, },
	118	{ .status = MNT3ERR_INVAL, .errno = -EINVAL, },
	119	{ .status = MNT3ERR_NAMETOOLONG, .errno = -ENAMETOOLONG, },
	120	{ .status = MNT3ERR_NOTSUPP, .errno = -ENOTSUPP, },
fdcb4577	121	{ .status = MNT3ERR_SERVERFAULT, .errno = -EREMOTEIO, },
fb125295 CL	122	};
	123
	124	struct mountres {
	125	int errno;
	126	struct nfs_fh *fh;
a14017db CL	127	unsigned int *auth_count;
a14017db CL	128	rpc_authflavor_t *auth_flavors;
fb125295 CL	129	};
fb125295 CL	130
1da177e4	131	struct mnt_fhstatus {
19207231 CL	132	u32 status;
19207231 CL	133	struct nfs_fh *fh;
1da177e4 LT	134	};
1da177e4 LT	135
3ea97309 CL	136	/**
3ea97309 CL	137	* nfs_mount - Obtain an NFS file handle for the given host and path
c5d120f8	138	* @info: pointer to mount request arguments
c9301cb3 EG	139	* @timeo: deciseconds the mount waits for a response before it retries
c9301cb3 EG	140	* @retrans: number of times the mount retries a request
3ea97309	141	*
c9301cb3 EG	142	* Uses timeout parameters specified by caller. On successful return, the
	143	* auth_flavs list and auth_flav_len will be populated with the list from the
	144	* server or a faked-up list if the server didn't provide one.
1da177e4	145	*/
c9301cb3	146	int nfs_mount(struct nfs_mount_request *info, int timeo, int retrans)
1da177e4	147	{
c9301cb3	148	struct rpc_timeout mnt_timeout;
8e02f6b9 CL	149	struct mountres result = {
	150	.fh = info->fh,
	151	.auth_count = info->auth_flav_len,
	152	.auth_flavors = info->auth_flavs,
1da177e4	153	};
dead28da	154	struct rpc_message msg = {
c5d120f8	155	.rpc_argp = info->dirpath,
dead28da CL	156	.rpc_resp = &result,
dead28da CL	157	};
3ea97309	158	struct rpc_create_args args = {
6d59b8d5	159	.net = info->net,
c5d120f8 CL	160	.protocol = info->protocol,
	161	.address = info->sap,
	162	.addrsize = info->salen,
c9301cb3	163	.timeout = &mnt_timeout,
c5d120f8	164	.servername = info->hostname,
3ea97309	165	.program = &mnt_program,
c5d120f8	166	.version = info->version,
3ea97309	167	.authflavor = RPC_AUTH_UNIX,
79caa5fa	168	.cred = current_cred(),
3ea97309 CL	169	};
3ea97309 CL	170	struct rpc_clnt *mnt_clnt;
1da177e4	171	int status;
1da177e4	172
3ea97309	173	dprintk("NFS: sending MNT request for %s:%s\n",
c5d120f8 CL	174	(info->hostname ? info->hostname : "server"),
c5d120f8 CL	175	info->dirpath);
1da177e4	176
28d79ea3 TM	177	if (strlen(info->dirpath) > MNTPATHLEN)
	178	return -ENAMETOOLONG;
	179
50a737f8 CL	180	if (info->noresvport)
	181	args.flags \|= RPC_CLNT_CREATE_NONPRIVPORT;
	182
c9301cb3	183	nfs_init_timeout_values(&mnt_timeout, info->protocol, timeo, retrans);
3ea97309	184	mnt_clnt = rpc_create(&args);
1da177e4	185	if (IS_ERR(mnt_clnt))
013a8c1a	186	goto out_clnt_err;
1da177e4	187
c5d120f8	188	if (info->version == NFS_MNT3_VERSION)
dead28da CL	189	msg.rpc_proc = &mnt_clnt->cl_procinfo[MOUNTPROC3_MNT];
dead28da CL	190	else
2ad78097	191	msg.rpc_proc = &mnt_clnt->cl_procinfo[MOUNTPROC_MNT];
dead28da	192
acce94e6	193	status = rpc_call_sync(mnt_clnt, &msg, RPC_TASK_SOFT\|RPC_TASK_TIMEOUT);
90c5755f	194	rpc_shutdown_client(mnt_clnt);
013a8c1a CL	195
	196	if (status < 0)
	197	goto out_call_err;
8e02f6b9	198	if (result.errno != 0)
013a8c1a CL	199	goto out_mnt_err;
	200
	201	dprintk("NFS: MNT request succeeded\n");
	202	status = 0;
	203
fb9b02fd JL	204	/*
	205	* If the server didn't provide a flavor list, allow the
	206	* client to try any flavor.
	207	*/
	208	if (info->version != NFS_MNT3_VERSION \|\| *info->auth_flav_len == 0) {
	209	dprintk("NFS: Faking up auth_flavs list\n");
	210	info->auth_flavs[0] = RPC_AUTH_NULL;
	211	*info->auth_flav_len = 1;
	212	}
013a8c1a CL	213	out:
	214	return status;
	215
	216	out_clnt_err:
	217	status = PTR_ERR(mnt_clnt);
8e02f6b9	218	dprintk("NFS: failed to create MNT RPC client, status=%d\n", status);
013a8c1a CL	219	goto out;
	220
	221	out_call_err:
8e02f6b9	222	dprintk("NFS: MNT request failed, status=%d\n", status);
013a8c1a CL	223	goto out;
	224
	225	out_mnt_err:
8e02f6b9 CL	226	dprintk("NFS: MNT server returned result %d\n", result.errno);
8e02f6b9 CL	227	status = result.errno;
013a8c1a	228	goto out;
1da177e4 LT	229	}
1da177e4 LT	230
0b524123 CL	231	/**
	232	* nfs_umount - Notify a server that we have unmounted this export
	233	* @info: pointer to umount request arguments
	234	*
	235	* MOUNTPROC_UMNT is advisory, so we set a short timeout, and always
	236	* use UDP.
	237	*/
	238	void nfs_umount(const struct nfs_mount_request *info)
	239	{
	240	static const struct rpc_timeout nfs_umnt_timeout = {
	241	.to_initval = 1 * HZ,
	242	.to_maxval = 3 * HZ,
	243	.to_retries = 2,
	244	};
	245	struct rpc_create_args args = {
6d59b8d5	246	.net = info->net,
0b524123 CL	247	.protocol = IPPROTO_UDP,
	248	.address = info->sap,
	249	.addrsize = info->salen,
	250	.timeout = &nfs_umnt_timeout,
	251	.servername = info->hostname,
	252	.program = &mnt_program,
	253	.version = info->version,
	254	.authflavor = RPC_AUTH_UNIX,
	255	.flags = RPC_CLNT_CREATE_NOPING,
79caa5fa	256	.cred = current_cred(),
0b524123	257	};
0b524123 CL	258	struct rpc_message msg = {
0b524123 CL	259	.rpc_argp = info->dirpath,
0b524123 CL	260	};
	261	struct rpc_clnt *clnt;
	262	int status;
	263
28d79ea3 TM	264	if (strlen(info->dirpath) > MNTPATHLEN)
	265	return;
	266
0b524123 CL	267	if (info->noresvport)
	268	args.flags \|= RPC_CLNT_CREATE_NONPRIVPORT;
	269
	270	clnt = rpc_create(&args);
c8b031eb	271	if (IS_ERR(clnt))
0b524123 CL	272	goto out_clnt_err;
	273
	274	dprintk("NFS: sending UMNT request for %s:%s\n",
	275	(info->hostname ? info->hostname : "server"), info->dirpath);
	276
	277	if (info->version == NFS_MNT3_VERSION)
	278	msg.rpc_proc = &clnt->cl_procinfo[MOUNTPROC3_UMNT];
	279	else
	280	msg.rpc_proc = &clnt->cl_procinfo[MOUNTPROC_UMNT];
	281
	282	status = rpc_call_sync(clnt, &msg, 0);
	283	rpc_shutdown_client(clnt);
	284
	285	if (unlikely(status < 0))
	286	goto out_call_err;
	287
	288	return;
	289
	290	out_clnt_err:
	291	dprintk("NFS: failed to create UMNT RPC client, status=%ld\n",
	292	PTR_ERR(clnt));
	293	return;
	294
	295	out_call_err:
	296	dprintk("NFS: UMNT request failed, status=%d\n", status);
	297	}
	298
1da177e4 LT	299	/*
	300	* XDR encode/decode functions for MOUNT
	301	*/
1da177e4	302
98eb2b4f	303	static void encode_mntdirpath(struct xdr_stream xdr, const char pathname)
29a1bd6b CL	304	{
	305	const u32 pathname_len = strlen(pathname);
	306	__be32 *p;
	307
98eb2b4f	308	p = xdr_reserve_space(xdr, 4 + pathname_len);
29a1bd6b	309	xdr_encode_opaque(p, pathname, pathname_len);
29a1bd6b CL	310	}
29a1bd6b CL	311
9f06c719	312	static void mnt_xdr_enc_dirpath(struct rpc_rqst req, struct xdr_stream xdr,
fcc85819	313	const void *dirpath)
29a1bd6b	314	{
9f06c719	315	encode_mntdirpath(xdr, dirpath);
29a1bd6b CL	316	}
29a1bd6b CL	317
fb125295 CL	318	/*
	319	* RFC 1094: "A non-zero status indicates some sort of error. In this
	320	* case, the status is a UNIX error number." This can be problematic
	321	* if the server and client use different errno values for the same
	322	* error.
	323	*
	324	* However, the OpenGroup XNFS spec provides a simple mapping that is
	325	* independent of local errno values on the server and the client.
	326	*/
	327	static int decode_status(struct xdr_stream xdr, struct mountres res)
	328	{
	329	unsigned int i;
	330	u32 status;
	331	__be32 *p;
	332
98eb2b4f	333	p = xdr_inline_decode(xdr, 4);
fb125295 CL	334	if (unlikely(p == NULL))
fb125295 CL	335	return -EIO;
98eb2b4f	336	status = be32_to_cpup(p);
fb125295	337
dd8ac1da	338	for (i = 0; i < ARRAY_SIZE(mnt_errtbl); i++) {
fb125295 CL	339	if (mnt_errtbl[i].status == status) {
	340	res->errno = mnt_errtbl[i].errno;
	341	return 0;
	342	}
	343	}
	344
	345	dprintk("NFS: unrecognized MNT status code: %u\n", status);
	346	res->errno = -EACCES;
	347	return 0;
	348	}
	349
4fdcd996 CL	350	static int decode_fhandle(struct xdr_stream xdr, struct mountres res)
	351	{
	352	struct nfs_fh *fh = res->fh;
	353	__be32 *p;
	354
	355	p = xdr_inline_decode(xdr, NFS2_FHSIZE);
	356	if (unlikely(p == NULL))
	357	return -EIO;
	358
	359	fh->size = NFS2_FHSIZE;
	360	memcpy(fh->data, p, NFS2_FHSIZE);
	361	return 0;
	362	}
	363
bf269551 CL	364	static int mnt_xdr_dec_mountres(struct rpc_rqst *req,
bf269551 CL	365	struct xdr_stream *xdr,
fc016483	366	void *data)
8e02f6b9	367	{
fc016483	368	struct mountres *res = data;
8e02f6b9 CL	369	int status;
8e02f6b9 CL	370
bf269551	371	status = decode_status(xdr, res);
8e02f6b9 CL	372	if (unlikely(status != 0 \|\| res->errno != 0))
8e02f6b9 CL	373	return status;
bf269551	374	return decode_fhandle(xdr, res);
8e02f6b9 CL	375	}
8e02f6b9 CL	376
fb125295 CL	377	static int decode_fhs_status(struct xdr_stream xdr, struct mountres res)
	378	{
	379	unsigned int i;
	380	u32 status;
	381	__be32 *p;
	382
98eb2b4f	383	p = xdr_inline_decode(xdr, 4);
fb125295 CL	384	if (unlikely(p == NULL))
fb125295 CL	385	return -EIO;
98eb2b4f	386	status = be32_to_cpup(p);
fb125295	387
dd8ac1da	388	for (i = 0; i < ARRAY_SIZE(mnt3_errtbl); i++) {
fb125295 CL	389	if (mnt3_errtbl[i].status == status) {
	390	res->errno = mnt3_errtbl[i].errno;
	391	return 0;
	392	}
	393	}
	394
	395	dprintk("NFS: unrecognized MNT3 status code: %u\n", status);
	396	res->errno = -EACCES;
	397	return 0;
	398	}
	399
4fdcd996 CL	400	static int decode_fhandle3(struct xdr_stream xdr, struct mountres res)
	401	{
	402	struct nfs_fh *fh = res->fh;
	403	u32 size;
	404	__be32 *p;
	405
98eb2b4f	406	p = xdr_inline_decode(xdr, 4);
4fdcd996 CL	407	if (unlikely(p == NULL))
	408	return -EIO;
	409
98eb2b4f	410	size = be32_to_cpup(p);
4fdcd996 CL	411	if (size > NFS3_FHSIZE \|\| size == 0)
	412	return -EIO;
	413
	414	p = xdr_inline_decode(xdr, size);
	415	if (unlikely(p == NULL))
	416	return -EIO;
	417
	418	fh->size = size;
	419	memcpy(fh->data, p, size);
	420	return 0;
	421	}
	422
a14017db CL	423	static int decode_auth_flavors(struct xdr_stream xdr, struct mountres res)
	424	{
	425	rpc_authflavor_t *flavors = res->auth_flavors;
	426	unsigned int *count = res->auth_count;
	427	u32 entries, i;
	428	__be32 *p;
	429
	430	if (*count == 0)
	431	return 0;
	432
98eb2b4f	433	p = xdr_inline_decode(xdr, 4);
a14017db CL	434	if (unlikely(p == NULL))
a14017db CL	435	return -EIO;
98eb2b4f	436	entries = be32_to_cpup(p);
a14017db CL	437	dprintk("NFS: received %u auth flavors\n", entries);
	438	if (entries > NFS_MAX_SECFLAVORS)
	439	entries = NFS_MAX_SECFLAVORS;
	440
98eb2b4f	441	p = xdr_inline_decode(xdr, 4 * entries);
a14017db CL	442	if (unlikely(p == NULL))
	443	return -EIO;
	444
	445	if (entries > *count)
	446	entries = *count;
	447
	448	for (i = 0; i < entries; i++) {
98eb2b4f	449	flavors[i] = be32_to_cpup(p++);
ed58b291	450	dprintk("NFS: auth flavor[%u]: %d\n", i, flavors[i]);
a14017db CL	451	}
	452	*count = i;
	453
	454	return 0;
	455	}
	456
bf269551 CL	457	static int mnt_xdr_dec_mountres3(struct rpc_rqst *req,
bf269551 CL	458	struct xdr_stream *xdr,
fc016483	459	void *data)
8e02f6b9	460	{
fc016483	461	struct mountres *res = data;
8e02f6b9 CL	462	int status;
8e02f6b9 CL	463
bf269551	464	status = decode_fhs_status(xdr, res);
8e02f6b9 CL	465	if (unlikely(status != 0 \|\| res->errno != 0))
8e02f6b9 CL	466	return status;
bf269551	467	status = decode_fhandle3(xdr, res);
8e02f6b9 CL	468	if (unlikely(status != 0)) {
	469	res->errno = -EBADHANDLE;
	470	return 0;
	471	}
bf269551	472	return decode_auth_flavors(xdr, res);
8e02f6b9 CL	473	}
8e02f6b9 CL	474
511e936b	475	static const struct rpc_procinfo mnt_procedures[] = {
2ad78097 CL	476	[MOUNTPROC_MNT] = {
2ad78097 CL	477	.p_proc = MOUNTPROC_MNT,
fcc85819	478	.p_encode = mnt_xdr_enc_dirpath,
fc016483	479	.p_decode = mnt_xdr_dec_mountres,
29a1bd6b	480	.p_arglen = MNT_enc_dirpath_sz,
8e02f6b9	481	.p_replen = MNT_dec_mountres_sz,
2ad78097	482	.p_statidx = MOUNTPROC_MNT,
19207231	483	.p_name = "MOUNT",
1da177e4	484	},
0b524123 CL	485	[MOUNTPROC_UMNT] = {
0b524123 CL	486	.p_proc = MOUNTPROC_UMNT,
fcc85819	487	.p_encode = mnt_xdr_enc_dirpath,
0b524123 CL	488	.p_arglen = MNT_enc_dirpath_sz,
	489	.p_statidx = MOUNTPROC_UMNT,
	490	.p_name = "UMOUNT",
	491	},
1da177e4 LT	492	};
1da177e4 LT	493
511e936b	494	static const struct rpc_procinfo mnt3_procedures[] = {
19207231 CL	495	[MOUNTPROC3_MNT] = {
19207231 CL	496	.p_proc = MOUNTPROC3_MNT,
fcc85819	497	.p_encode = mnt_xdr_enc_dirpath,
fc016483	498	.p_decode = mnt_xdr_dec_mountres3,
29a1bd6b	499	.p_arglen = MNT_enc_dirpath_sz,
8e02f6b9	500	.p_replen = MNT_dec_mountres3_sz,
19207231 CL	501	.p_statidx = MOUNTPROC3_MNT,
19207231 CL	502	.p_name = "MOUNT",
1da177e4	503	},
0b524123 CL	504	[MOUNTPROC3_UMNT] = {
0b524123 CL	505	.p_proc = MOUNTPROC3_UMNT,
fcc85819	506	.p_encode = mnt_xdr_enc_dirpath,
0b524123 CL	507	.p_arglen = MNT_enc_dirpath_sz,
	508	.p_statidx = MOUNTPROC3_UMNT,
	509	.p_name = "UMOUNT",
	510	},
1da177e4 LT	511	};
1da177e4 LT	512
c551858a	513	static unsigned int mnt_counts[ARRAY_SIZE(mnt_procedures)];
a613fa16	514	static const struct rpc_version mnt_version1 = {
19207231	515	.number = 1,
5b362ac3	516	.nrprocs = ARRAY_SIZE(mnt_procedures),
19207231	517	.procs = mnt_procedures,
c551858a	518	.counts = mnt_counts,
1da177e4 LT	519	};
1da177e4 LT	520
ecc7b435	521	static unsigned int mnt3_counts[ARRAY_SIZE(mnt3_procedures)];
a613fa16	522	static const struct rpc_version mnt_version3 = {
19207231	523	.number = 3,
5b362ac3	524	.nrprocs = ARRAY_SIZE(mnt3_procedures),
19207231	525	.procs = mnt3_procedures,
c551858a	526	.counts = mnt3_counts,
1da177e4 LT	527	};
1da177e4 LT	528
a613fa16	529	static const struct rpc_version *mnt_version[] = {
1da177e4 LT	530	NULL,
	531	&mnt_version1,
	532	NULL,
	533	&mnt_version3,
	534	};
	535
19207231	536	static struct rpc_stat mnt_stats;
1da177e4	537
a613fa16	538	static const struct rpc_program mnt_program = {
1da177e4 LT	539	.name = "mount",
1da177e4 LT	540	.number = NFS_MNT_PROGRAM,
e8c96f8c	541	.nrvers = ARRAY_SIZE(mnt_version),
1da177e4 LT	542	.version = mnt_version,
	543	.stats = &mnt_stats,
	544	};