Commit f74a14e8 authored by Richard Weinberger's avatar Richard Weinberger
Browse files

um: Remove hppfs 



hppfs (honeypot procfs) was an attempt to use UML as honeypot.
It was never stable nor in heavy use.

As Al Viro and Christoph Hellwig pointed some major issues out
it is better to let it die.

Signed-off-by: default avatarRichard Weinberger <richard@nod.at>
parent 89520d99

arch/um/Kconfig.um

+0 −15
Original line number Diff line number Diff line
@@ -44,21 +44,6 @@ config HOSTFS 
          If you'd like to be able to work with files stored on the host,

          say Y or M here; otherwise say N.



config HPPFS

	tristate "HoneyPot ProcFS"

	depends on PROC_FS

	help

	  hppfs (HoneyPot ProcFS) is a filesystem which allows UML /proc

	  entries to be overridden, removed, or fabricated from the host.

	  Its purpose is to allow a UML to appear to be a physical machine

	  by removing or changing anything in /proc which gives away the

	  identity of a UML.



	  See <http://user-mode-linux.sf.net/old/hppfs.html> for more information.



	  You only need this if you are setting up a UML honeypot.  Otherwise,

	  it is safe to say 'N' here.



config MCONSOLE

	bool "Management console"

	default y

fs/Makefile

+0 −1
Original line number Diff line number Diff line
@@ -115,7 +115,6 @@ obj-$(CONFIG_AFS_FS) += afs/ 
obj-$(CONFIG_NILFS2_FS)		+= nilfs2/

obj-$(CONFIG_BEFS_FS)		+= befs/

obj-$(CONFIG_HOSTFS)		+= hostfs/

obj-$(CONFIG_HPPFS)		+= hppfs/

obj-$(CONFIG_CACHEFILES)	+= cachefiles/

obj-$(CONFIG_DEBUG_FS)		+= debugfs/

obj-$(CONFIG_TRACING)		+= tracefs/

fs/hppfs/Makefile

deleted100644 → 0
+0 −6
Original line number Diff line number Diff line 
#

# Copyright (C) 2002 - 2008 Jeff Dike (jdike@{addtoit,linux.intel}.com)

# Licensed under the GPL

#



obj-$(CONFIG_HPPFS) += hppfs.o

fs/hppfs/hppfs.c

deleted100644 → 0
+0 −766
Original line number Diff line number Diff line 
/*

 * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)

 * Licensed under the GPL

 */



#include <linux/ctype.h>

#include <linux/dcache.h>

#include <linux/file.h>

#include <linux/fs.h>

#include <linux/init.h>

#include <linux/kernel.h>

#include <linux/list.h>

#include <linux/module.h>

#include <linux/mount.h>

#include <linux/slab.h>

#include <linux/statfs.h>

#include <linux/types.h>

#include <linux/pid_namespace.h>

#include <linux/namei.h>

#include <asm/uaccess.h>

#include <os.h>



static struct inode *get_inode(struct super_block *, struct dentry *);



struct hppfs_data {

	struct list_head list;

	char contents[PAGE_SIZE - sizeof(struct list_head)];

};



struct hppfs_private {

	struct file *proc_file;

	int host_fd;

	loff_t len;

	struct hppfs_data *contents;

};



struct hppfs_inode_info {

	struct dentry *proc_dentry;

	struct inode vfs_inode;

};



static inline struct hppfs_inode_info *HPPFS_I(struct inode *inode)

{

	return container_of(inode, struct hppfs_inode_info, vfs_inode);

}



#define HPPFS_SUPER_MAGIC 0xb00000ee



static const struct super_operations hppfs_sbops;



static int is_pid(struct dentry *dentry)

{

	struct super_block *sb;

	int i;



	sb = dentry->d_sb;

	if (dentry->d_parent != sb->s_root)

		return 0;



	for (i = 0; i < dentry->d_name.len; i++) {

		if (!isdigit(dentry->d_name.name[i]))

			return 0;

	}

	return 1;

}



static char *dentry_name(struct dentry *dentry, int extra)

{

	struct dentry *parent;

	char *root, *name;

	const char *seg_name;

	int len, seg_len, root_len;



	len = 0;

	parent = dentry;

	while (parent->d_parent != parent) {

		if (is_pid(parent))

			len += strlen("pid") + 1;

		else len += parent->d_name.len + 1;

		parent = parent->d_parent;

	}



	root = "proc";

	root_len = strlen(root);

	len += root_len;

	name = kmalloc(len + extra + 1, GFP_KERNEL);

	if (name == NULL)

		return NULL;



	name[len] = '\0';

	parent = dentry;

	while (parent->d_parent != parent) {

		if (is_pid(parent)) {

			seg_name = "pid";

			seg_len = strlen(seg_name);

		}

		else {

			seg_name = parent->d_name.name;

			seg_len = parent->d_name.len;

		}



		len -= seg_len + 1;

		name[len] = '/';

		memcpy(&name[len + 1], seg_name, seg_len);

		parent = parent->d_parent;

	}

	memcpy(name, root, root_len);

	return name;

}



static int file_removed(struct dentry *dentry, const char *file)

{

	char *host_file;

	int extra, fd;



	extra = 0;

	if (file != NULL)

		extra += strlen(file) + 1;



	host_file = dentry_name(dentry, extra + strlen("/remove"));

	if (host_file == NULL) {

		printk(KERN_ERR "file_removed : allocation failed\n");

		return -ENOMEM;

	}



	if (file != NULL) {

		strcat(host_file, "/");

		strcat(host_file, file);

	}

	strcat(host_file, "/remove");



	fd = os_open_file(host_file, of_read(OPENFLAGS()), 0);

	kfree(host_file);

	if (fd > 0) {

		os_close_file(fd);

		return 1;

	}

	return 0;

}



static struct dentry *hppfs_lookup(struct inode *ino, struct dentry *dentry,

				   unsigned int flags)

{

	struct dentry *proc_dentry, *parent;

	struct qstr *name = &dentry->d_name;

	struct inode *inode;

	int err, deleted;



	deleted = file_removed(dentry, NULL);

	if (deleted < 0)

		return ERR_PTR(deleted);

	else if (deleted)

		return ERR_PTR(-ENOENT);



	parent = HPPFS_I(ino)->proc_dentry;

	mutex_lock(&d_inode(parent)->i_mutex);

	proc_dentry = lookup_one_len(name->name, parent, name->len);

	mutex_unlock(&d_inode(parent)->i_mutex);



	if (IS_ERR(proc_dentry))

		return proc_dentry;



	err = -ENOMEM;

	inode = get_inode(ino->i_sb, proc_dentry);

	if (!inode)

		goto out;



 	d_add(dentry, inode);

	return NULL;



 out:

	return ERR_PTR(err);

}



static const struct inode_operations hppfs_file_iops = {

};



static ssize_t read_proc(struct file *file, char __user *buf, ssize_t count,

			 loff_t *ppos, int is_user)

{

	ssize_t (*read)(struct file *, char __user *, size_t, loff_t *);

	ssize_t n;



	read = file_inode(file)->i_fop->read;



	if (!is_user)

		set_fs(KERNEL_DS);



	n = (*read)(file, buf, count, &file->f_pos);



	if (!is_user)

		set_fs(USER_DS);



	if (ppos)

		*ppos = file->f_pos;

	return n;

}



static ssize_t hppfs_read_file(int fd, char __user *buf, ssize_t count)

{

	ssize_t n;

	int cur, err;

	char *new_buf;



	n = -ENOMEM;

	new_buf = kmalloc(PAGE_SIZE, GFP_KERNEL);

	if (new_buf == NULL) {

		printk(KERN_ERR "hppfs_read_file : kmalloc failed\n");

		goto out;

	}

	n = 0;

	while (count > 0) {

		cur = min_t(ssize_t, count, PAGE_SIZE);

		err = os_read_file(fd, new_buf, cur);

		if (err < 0) {

			printk(KERN_ERR "hppfs_read : read failed, "

			       "errno = %d\n", err);

			n = err;

			goto out_free;

		} else if (err == 0)

			break;



		if (copy_to_user(buf, new_buf, err)) {

			n = -EFAULT;

			goto out_free;

		}

		n += err;

		count -= err;

	}

 out_free:

	kfree(new_buf);

 out:

	return n;

}



static ssize_t hppfs_read(struct file *file, char __user *buf, size_t count,

			  loff_t *ppos)

{

	struct hppfs_private *hppfs = file->private_data;

	struct hppfs_data *data;

	loff_t off;

	int err;



	if (hppfs->contents != NULL) {

		int rem;



		if (*ppos >= hppfs->len)

			return 0;



		data = hppfs->contents;

		off = *ppos;

		while (off >= sizeof(data->contents)) {

			data = list_entry(data->list.next, struct hppfs_data,

					  list);

			off -= sizeof(data->contents);

		}



		if (off + count > hppfs->len)

			count = hppfs->len - off;

		rem = copy_to_user(buf, &data->contents[off], count);

		*ppos += count - rem;

		if (rem > 0)

			return -EFAULT;

	} else if (hppfs->host_fd != -1) {

		err = os_seek_file(hppfs->host_fd, *ppos);

		if (err) {

			printk(KERN_ERR "hppfs_read : seek failed, "

			       "errno = %d\n", err);

			return err;

		}

		err = hppfs_read_file(hppfs->host_fd, buf, count);

		if (err < 0) {

			printk(KERN_ERR "hppfs_read: read failed: %d\n", err);

			return err;

		}

		count = err;

		if (count > 0)

			*ppos += count;

	}

	else count = read_proc(hppfs->proc_file, buf, count, ppos, 1);



	return count;

}



static ssize_t hppfs_write(struct file *file, const char __user *buf,

			   size_t len, loff_t *ppos)

{

	struct hppfs_private *data = file->private_data;

	struct file *proc_file = data->proc_file;

	ssize_t (*write)(struct file *, const char __user *, size_t, loff_t *);



	write = file_inode(proc_file)->i_fop->write;

	return (*write)(proc_file, buf, len, ppos);

}



static int open_host_sock(char *host_file, int *filter_out)

{

	char *end;

	int fd;



	end = &host_file[strlen(host_file)];

	strcpy(end, "/rw");

	*filter_out = 1;

	fd = os_connect_socket(host_file);

	if (fd > 0)

		return fd;



	strcpy(end, "/r");

	*filter_out = 0;

	fd = os_connect_socket(host_file);

	return fd;

}



static void free_contents(struct hppfs_data *head)

{

	struct hppfs_data *data;

	struct list_head *ele, *next;



	if (head == NULL)

		return;



	list_for_each_safe(ele, next, &head->list) {

		data = list_entry(ele, struct hppfs_data, list);

		kfree(data);

	}

	kfree(head);

}



static struct hppfs_data *hppfs_get_data(int fd, int filter,

					 struct file *proc_file,

					 struct file *hppfs_file,

					 loff_t *size_out)

{

	struct hppfs_data *data, *new, *head;

	int n, err;



	err = -ENOMEM;

	data = kmalloc(sizeof(*data), GFP_KERNEL);

	if (data == NULL) {

		printk(KERN_ERR "hppfs_get_data : head allocation failed\n");

		goto failed;

	}



	INIT_LIST_HEAD(&data->list);



	head = data;

	*size_out = 0;



	if (filter) {

		while ((n = read_proc(proc_file, data->contents,

				      sizeof(data->contents), NULL, 0)) > 0)

			os_write_file(fd, data->contents, n);

		err = os_shutdown_socket(fd, 0, 1);

		if (err) {

			printk(KERN_ERR "hppfs_get_data : failed to shut down "

			       "socket\n");

			goto failed_free;

		}

	}

	while (1) {

		n = os_read_file(fd, data->contents, sizeof(data->contents));

		if (n < 0) {

			err = n;

			printk(KERN_ERR "hppfs_get_data : read failed, "

			       "errno = %d\n", err);

			goto failed_free;

		} else if (n == 0)

			break;



		*size_out += n;



		if (n < sizeof(data->contents))

			break;



		new = kmalloc(sizeof(*data), GFP_KERNEL);

		if (new == 0) {

			printk(KERN_ERR "hppfs_get_data : data allocation "

			       "failed\n");

			err = -ENOMEM;

			goto failed_free;

		}



		INIT_LIST_HEAD(&new->list);

		list_add(&new->list, &data->list);

		data = new;

	}

	return head;



 failed_free:

	free_contents(head);

 failed:

	return ERR_PTR(err);

}



static struct hppfs_private *hppfs_data(void)

{

	struct hppfs_private *data;



	data = kmalloc(sizeof(*data), GFP_KERNEL);

	if (data == NULL)

		return data;



	*data = ((struct hppfs_private ) { .host_fd  		= -1,

					   .len  		= -1,

					   .contents 		= NULL } );

	return data;

}



static int file_mode(int fmode)

{

	if (fmode == (FMODE_READ | FMODE_WRITE))

		return O_RDWR;

	if (fmode == FMODE_READ)

		return O_RDONLY;

	if (fmode == FMODE_WRITE)

		return O_WRONLY;

	return 0;

}



static int hppfs_open(struct inode *inode, struct file *file)

{

	const struct cred *cred = file->f_cred;

	struct hppfs_private *data;

	struct path path;

	char *host_file;

	int err, fd, type, filter;



	err = -ENOMEM;

	data = hppfs_data();

	if (data == NULL)

		goto out;



	host_file = dentry_name(file->f_path.dentry, strlen("/rw"));

	if (host_file == NULL)

		goto out_free2;



	path.mnt = inode->i_sb->s_fs_info;

	path.dentry = HPPFS_I(inode)->proc_dentry;



	data->proc_file = dentry_open(&path, file_mode(file->f_mode), cred);

	err = PTR_ERR(data->proc_file);

	if (IS_ERR(data->proc_file))

		goto out_free1;



	type = os_file_type(host_file);

	if (type == OS_TYPE_FILE) {

		fd = os_open_file(host_file, of_read(OPENFLAGS()), 0);

		if (fd >= 0)

			data->host_fd = fd;

		else

			printk(KERN_ERR "hppfs_open : failed to open '%s', "

			       "errno = %d\n", host_file, -fd);



		data->contents = NULL;

	} else if (type == OS_TYPE_DIR) {

		fd = open_host_sock(host_file, &filter);

		if (fd > 0) {

			data->contents = hppfs_get_data(fd, filter,

							data->proc_file,

							file, &data->len);

			if (!IS_ERR(data->contents))

				data->host_fd = fd;

		} else

			printk(KERN_ERR "hppfs_open : failed to open a socket "

			       "in '%s', errno = %d\n", host_file, -fd);

	}

	kfree(host_file);



	file->private_data = data;

	return 0;



 out_free1:

	kfree(host_file);

 out_free2:

	free_contents(data->contents);

	kfree(data);

 out:

	return err;

}



static int hppfs_dir_open(struct inode *inode, struct file *file)

{

	const struct cred *cred = file->f_cred;

	struct hppfs_private *data;

	struct path path;

	int err;



	err = -ENOMEM;

	data = hppfs_data();

	if (data == NULL)

		goto out;



	path.mnt = inode->i_sb->s_fs_info;

	path.dentry = HPPFS_I(inode)->proc_dentry;

	data->proc_file = dentry_open(&path, file_mode(file->f_mode), cred);

	err = PTR_ERR(data->proc_file);

	if (IS_ERR(data->proc_file))

		goto out_free;



	file->private_data = data;

	return 0;



 out_free:

	kfree(data);

 out:

	return err;

}



static loff_t hppfs_llseek(struct file *file, loff_t off, int where)

{

	struct hppfs_private *data = file->private_data;

	struct file *proc_file = data->proc_file;

	loff_t (*llseek)(struct file *, loff_t, int);

	loff_t ret;



	llseek = file_inode(proc_file)->i_fop->llseek;

	if (llseek != NULL) {

		ret = (*llseek)(proc_file, off, where);

		if (ret < 0)

			return ret;

	}



	return default_llseek(file, off, where);

}



static int hppfs_release(struct inode *inode, struct file *file)

{

	struct hppfs_private *data = file->private_data;

	struct file *proc_file = data->proc_file;

	if (proc_file)

		fput(proc_file);

	kfree(data);

	return 0;

}



static const struct file_operations hppfs_file_fops = {

	.owner		= NULL,

	.llseek		= hppfs_llseek,

	.read		= hppfs_read,

	.write		= hppfs_write,

	.open		= hppfs_open,

	.release	= hppfs_release,

};



struct hppfs_dirent {

	struct dir_context ctx;

	struct dir_context *caller;

	struct dentry *dentry;

};



static int hppfs_filldir(struct dir_context *ctx, const char *name, int size,

			 loff_t offset, u64 inode, unsigned int type)

{

	struct hppfs_dirent *dirent =

		container_of(ctx, struct hppfs_dirent, ctx);



	if (file_removed(dirent->dentry, name))

		return 0;



	dirent->caller->pos = dirent->ctx.pos;

	return !dir_emit(dirent->caller, name, size, inode, type);

}



static int hppfs_readdir(struct file *file, struct dir_context *ctx)

{

	struct hppfs_private *data = file->private_data;

	struct file *proc_file = data->proc_file;

	struct hppfs_dirent d = {

		.ctx.actor	= hppfs_filldir,

		.caller		= ctx,

		.dentry  	= file->f_path.dentry

	};

	int err;

	proc_file->f_pos = ctx->pos;

	err = iterate_dir(proc_file, &d.ctx);

	ctx->pos = d.ctx.pos;

	return err;

}



static const struct file_operations hppfs_dir_fops = {

	.owner		= NULL,

	.iterate	= hppfs_readdir,

	.open		= hppfs_dir_open,

	.llseek		= default_llseek,

	.release	= hppfs_release,

};



static int hppfs_statfs(struct dentry *dentry, struct kstatfs *sf)

{

	sf->f_blocks = 0;

	sf->f_bfree = 0;

	sf->f_bavail = 0;

	sf->f_files = 0;

	sf->f_ffree = 0;

	sf->f_type = HPPFS_SUPER_MAGIC;

	return 0;

}



static struct inode *hppfs_alloc_inode(struct super_block *sb)

{

	struct hppfs_inode_info *hi;



	hi = kmalloc(sizeof(*hi), GFP_KERNEL);

	if (!hi)

		return NULL;



	hi->proc_dentry = NULL;

	inode_init_once(&hi->vfs_inode);

	return &hi->vfs_inode;

}



void hppfs_evict_inode(struct inode *ino)

{

	clear_inode(ino);

	dput(HPPFS_I(ino)->proc_dentry);

	mntput(ino->i_sb->s_fs_info);

}



static void hppfs_i_callback(struct rcu_head *head)

{

	struct inode *inode = container_of(head, struct inode, i_rcu);

	kfree(HPPFS_I(inode));

}



static void hppfs_destroy_inode(struct inode *inode)

{

	call_rcu(&inode->i_rcu, hppfs_i_callback);

}



static const struct super_operations hppfs_sbops = {

	.alloc_inode	= hppfs_alloc_inode,

	.destroy_inode	= hppfs_destroy_inode,

	.evict_inode	= hppfs_evict_inode,

	.statfs		= hppfs_statfs,

};



static int hppfs_readlink(struct dentry *dentry, char __user *buffer,

			  int buflen)

{

	struct dentry *proc_dentry = HPPFS_I(d_inode(dentry))->proc_dentry;

	return d_inode(proc_dentry)->i_op->readlink(proc_dentry, buffer,

						    buflen);

}



static void *hppfs_follow_link(struct dentry *dentry, struct nameidata *nd)

{

	struct dentry *proc_dentry = HPPFS_I(d_inode(dentry))->proc_dentry;



	return d_inode(proc_dentry)->i_op->follow_link(proc_dentry, nd);

}



static void hppfs_put_link(struct dentry *dentry, struct nameidata *nd,

			   void *cookie)

{

	struct dentry *proc_dentry = HPPFS_I(d_inode(dentry))->proc_dentry;



	if (d_inode(proc_dentry)->i_op->put_link)

		d_inode(proc_dentry)->i_op->put_link(proc_dentry, nd, cookie);

}



static const struct inode_operations hppfs_dir_iops = {

	.lookup		= hppfs_lookup,

};



static const struct inode_operations hppfs_link_iops = {

	.readlink	= hppfs_readlink,

	.follow_link	= hppfs_follow_link,

	.put_link	= hppfs_put_link,

};



static struct inode *get_inode(struct super_block *sb, struct dentry *dentry)

{

	struct inode *proc_ino = d_inode(dentry);

	struct inode *inode = new_inode(sb);



	if (!inode) {

		dput(dentry);

		return NULL;

	}



	if (d_is_dir(dentry)) {

		inode->i_op = &hppfs_dir_iops;

		inode->i_fop = &hppfs_dir_fops;

	} else if (d_is_symlink(dentry)) {

		inode->i_op = &hppfs_link_iops;

		inode->i_fop = &hppfs_file_fops;

	} else {

		inode->i_op = &hppfs_file_iops;

		inode->i_fop = &hppfs_file_fops;

	}



	HPPFS_I(inode)->proc_dentry = dentry;



	inode->i_uid = proc_ino->i_uid;

	inode->i_gid = proc_ino->i_gid;

	inode->i_atime = proc_ino->i_atime;

	inode->i_mtime = proc_ino->i_mtime;

	inode->i_ctime = proc_ino->i_ctime;

	inode->i_ino = proc_ino->i_ino;

	inode->i_mode = proc_ino->i_mode;

	set_nlink(inode, proc_ino->i_nlink);

	inode->i_size = proc_ino->i_size;

	inode->i_blocks = proc_ino->i_blocks;



	return inode;

}



static int hppfs_fill_super(struct super_block *sb, void *d, int silent)

{

	struct inode *root_inode;

	struct vfsmount *proc_mnt;

	int err = -ENOENT;



	proc_mnt = mntget(task_active_pid_ns(current)->proc_mnt);

	if (IS_ERR(proc_mnt))

		goto out;



	sb->s_blocksize = 1024;

	sb->s_blocksize_bits = 10;

	sb->s_magic = HPPFS_SUPER_MAGIC;

	sb->s_op = &hppfs_sbops;

	sb->s_fs_info = proc_mnt;



	err = -ENOMEM;

	root_inode = get_inode(sb, dget(proc_mnt->mnt_root));

	sb->s_root = d_make_root(root_inode);

	if (!sb->s_root)

		goto out_mntput;



	return 0;



 out_mntput:

	mntput(proc_mnt);

 out:

	return(err);

}



static struct dentry *hppfs_read_super(struct file_system_type *type,

			    int flags, const char *dev_name,

			    void *data)

{

	return mount_nodev(type, flags, data, hppfs_fill_super);

}



static struct file_system_type hppfs_type = {

	.owner 		= THIS_MODULE,

	.name 		= "hppfs",

	.mount 		= hppfs_read_super,

	.kill_sb	= kill_anon_super,

	.fs_flags 	= 0,

};

MODULE_ALIAS_FS("hppfs");



static int __init init_hppfs(void)

{

	return register_filesystem(&hppfs_type);

}



static void __exit exit_hppfs(void)

{

	unregister_filesystem(&hppfs_type);

}



module_init(init_hppfs)

module_exit(exit_hppfs)

MODULE_LICENSE("GPL");

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