path: root/fs/nfsd/nfsctl.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Syscall interface to knfsd.
 *
 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
 */

#include <linux/slab.h>
#include <linux/namei.h>
#include <linux/ctype.h>
#include <linux/fs_context.h>

#include <linux/sunrpc/svcsock.h>
#include <linux/lockd/lockd.h>
#include <linux/sunrpc/addr.h>
#include <linux/sunrpc/gss_api.h>
#include <linux/sunrpc/gss_krb5_enctypes.h>
#include <linux/sunrpc/rpc_pipe_fs.h>
#include <linux/module.h>
#include <linux/fsnotify.h>

#include "idmap.h"
#include "nfsd.h"
#include "cache.h"
#include "state.h"
#include "netns.h"
#include "pnfs.h"
#include "filecache.h"

/*
 *	We have a single directory with several nodes in it.
 */
enum {
	NFSD_Root = 1,
	NFSD_List,
	NFSD_Export_Stats,
	NFSD_Export_features,
	NFSD_Fh,
	NFSD_FO_UnlockIP,
	NFSD_FO_UnlockFS,
	NFSD_Threads,
	NFSD_Pool_Threads,
	NFSD_Pool_Stats,
	NFSD_Reply_Cache_Stats,
	NFSD_Versions,
	NFSD_Ports,
	NFSD_MaxBlkSize,
	NFSD_MaxConnections,
	NFSD_Filecache,
	NFSD_SupportedEnctypes,
	/*
	 * The below MUST come last.  Otherwise we leave a hole in nfsd_files[]
	 * with !CONFIG_NFSD_V4 and simple_fill_super() goes oops
	 */
#ifdef CONFIG_NFSD_V4
	NFSD_Leasetime,
	NFSD_Gracetime,
	NFSD_RecoveryDir,
	NFSD_V4EndGrace,
#endif
	NFSD_MaxReserved
};

/*
 * write() for these nodes.
 */
static ssize_t write_filehandle(struct file *file, char *buf, size_t size);
static ssize_t write_unlock_ip(struct file *file, char *buf, size_t size);
static ssize_t write_unlock_fs(struct file *file, char *buf, size_t size);
static ssize_t write_threads(struct file *file, char *buf, size_t size);
static ssize_t write_pool_threads(struct file *file, char *buf, size_t size);
static ssize_t write_versions(struct file *file, char *buf, size_t size);
static ssize_t write_ports(struct file *file, char *buf, size_t size);
static ssize_t write_maxblksize(struct file *file, char *buf, size_t size);
static ssize_t write_maxconn(struct file *file, char *buf, size_t size);
#ifdef CONFIG_NFSD_V4
static ssize_t write_leasetime(struct file *file, char *buf, size_t size);
static ssize_t write_gracetime(struct file *file, char *buf, size_t size);
static ssize_t write_recoverydir(struct file *file, char *buf, size_t size);
static ssize_t write_v4_end_grace(struct file *file, char *buf, size_t size);
#endif

static ssize_t (*const write_op[])(struct file *, char *, size_t) = {
	[NFSD_Fh] = write_filehandle,
	[NFSD_FO_UnlockIP] = write_unlock_ip,
	[NFSD_FO_UnlockFS] = write_unlock_fs,
	[NFSD_Threads] = write_threads,
	[NFSD_Pool_Threads] = write_pool_threads,
	[NFSD_Versions] = write_versions,
	[NFSD_Ports] = write_ports,
	[NFSD_MaxBlkSize] = write_maxblksize,
	[NFSD_MaxConnections] = write_maxconn,
#ifdef CONFIG_NFSD_V4
	[NFSD_Leasetime] = write_leasetime,
	[NFSD_Gracetime] = write_gracetime,
	[NFSD_RecoveryDir] = write_recoverydir,
	[NFSD_V4EndGrace] = write_v4_end_grace,
#endif
};

static ssize_t nfsctl_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
{
	ino_t ino =  file_inode(file)->i_ino;
	char *data;
	ssize_t rv;

	if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
		return -EINVAL;

	data = simple_transaction_get(file, buf, size);
	if (IS_ERR(data))
		return PTR_ERR(data);

	rv =  write_op[ino](file, data, size);
	if (rv >= 0) {
		simple_transaction_set(file, rv);
		rv = size;
	}
	return rv;
}

static ssize_t nfsctl_transaction_read(struct file *file, char __user *buf, size_t size, loff_t *pos)
{
	if (! file->private_data) {
		/* An attempt to read a transaction file without writing
		 * causes a 0-byte write so that the file can return
		 * state information
		 */
		ssize_t rv = nfsctl_transaction_write(file, buf, 0, pos);
		if (rv < 0)
			return rv;
	}
	return simple_transaction_read(file, buf, size, pos);
}

static const struct file_operations transaction_ops = {
	.write		= nfsctl_transaction_write,
	.read		= nfsctl_transaction_read,
	.release	= simple_transaction_release,
	.llseek		= default_llseek,
};

static int exports_net_open(struct net *net, struct file *file)
{
	int err;
	struct seq_file *seq;
	struct nfsd_net *nn = net_generic(net, nfsd_net_id);

	err = seq_open(file, &nfs_exports_op);
	if (err)
		return err;

	seq = file->private_data;
	seq->private = nn->svc_export_cache;
	return 0;
}

static int exports_proc_open(struct inode *inode, struct file *file)
{
	return exports_net_open(current->nsproxy->net_ns, file);
}

static const struct proc_ops exports_proc_ops = {
	.proc_open	= exports_proc_open,
	.proc_read	= seq_read,
	.proc_lseek	= seq_lseek,
	.proc_release	= seq_release,
};

static int exports_nfsd_open(struct inode *inode, struct file *file)
{
	return exports_net_open(inode->i_sb->s_fs_info, file);
}

static const struct file_operations exports_nfsd_operations = {
	.open		= exports_nfsd_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= seq_release,
};

static int export_features_show(struct seq_file *m, void *v)
{
	seq_printf(m, "0x%x 0x%x\n", NFSEXP_ALLFLAGS, NFSEXP_SECINFO_FLAGS);
	return 0;
}

DEFINE_SHOW_ATTRIBUTE(export_features);

#if defined(CONFIG_SUNRPC_GSS) || defined(CONFIG_SUNRPC_GSS_MODULE)
static int supported_enctypes_show(struct seq_file *m, void *v)
{
	seq_printf(m, KRB5_SUPPORTED_ENCTYPES);
	return 0;
}

DEFINE_SHOW_ATTRIBUTE(supported_enctypes);
#endif /* CONFIG_SUNRPC_GSS or CONFIG_SUNRPC_GSS_MODULE */

static const struct file_operations pool_stats_operations = {
	.open		= nfsd_pool_stats_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= nfsd_pool_stats_release,
};

DEFINE_SHOW_ATTRIBUTE(nfsd_reply_cache_stats);

DEFINE_SHOW_ATTRIBUTE(nfsd_file_cache_stats);

/*----------------------------------------------------------------------------*/
/*
 * payload - write methods
 */

static inline struct net *netns(struct file *file)
{
	return file_inode(file)->i_sb->s_fs_info;
}

/*
 * write_unlock_ip - Release all locks used by a client
 *
 * Experimental.
 *
 * Input:
 *			buf:	'\n'-terminated C string containing a
 *				presentation format IP address
 *			size:	length of C string in @buf
 * Output:
 *	On success:	returns zero if all specified locks were released;
 *			returns one if one or more locks were not released
 *	On error:	return code is negative errno value
 */
static ssize_t write_unlock_ip(struct file *file, char *buf, size_t size)
{
	struct sockaddr_storage address;
	struct sockaddr *sap = (struct sockaddr *)&address;
	size_t salen = sizeof(address);
	char *fo_path;
	struct net *net = netns(file);

	/* sanity check */
	if (size =