smack_lsm.c 117.1 KB
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/*
 *  Simplified MAC Kernel (smack) security module
 *
 *  This file contains the smack hook function implementations.
 *
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 *  Authors:
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 *	Casey Schaufler <casey@schaufler-ca.com>
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 *	Jarkko Sakkinen <jarkko.sakkinen@intel.com>
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 *
 *  Copyright (C) 2007 Casey Schaufler <casey@schaufler-ca.com>
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 *  Copyright (C) 2009 Hewlett-Packard Development Company, L.P.
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 *                Paul Moore <paul@paul-moore.com>
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 *  Copyright (C) 2010 Nokia Corporation
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 *  Copyright (C) 2011 Intel Corporation.
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 *
 *	This program is free software; you can redistribute it and/or modify
 *	it under the terms of the GNU General Public License version 2,
 *      as published by the Free Software Foundation.
 */

#include <linux/xattr.h>
#include <linux/pagemap.h>
#include <linux/mount.h>
#include <linux/stat.h>
#include <linux/kd.h>
#include <asm/ioctls.h>
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#include <linux/ip.h>
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#include <linux/tcp.h>
#include <linux/udp.h>
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#include <linux/dccp.h>
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#include <linux/slab.h>
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#include <linux/mutex.h>
#include <linux/pipe_fs_i.h>
#include <net/cipso_ipv4.h>
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#include <net/ip.h>
#include <net/ipv6.h>
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#include <linux/audit.h>
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#include <linux/magic.h>
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#include <linux/dcache.h>
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#include <linux/personality.h>
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#include <linux/msg.h>
#include <linux/shm.h>
#include <linux/binfmts.h>
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#include <linux/parser.h>
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#include "smack.h"

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#define TRANS_TRUE	"TRUE"
#define TRANS_TRUE_SIZE	4

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#define SMK_CONNECTING	0
#define SMK_RECEIVING	1
#define SMK_SENDING	2

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#ifdef SMACK_IPV6_PORT_LABELING
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DEFINE_MUTEX(smack_ipv6_lock);
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static LIST_HEAD(smk_ipv6_port_list);
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#endif
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static struct kmem_cache *smack_inode_cache;
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int smack_enabled;
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static const match_table_t smk_mount_tokens = {
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	{Opt_fsdefault, SMK_FSDEFAULT "%s"},
	{Opt_fsfloor, SMK_FSFLOOR "%s"},
	{Opt_fshat, SMK_FSHAT "%s"},
	{Opt_fsroot, SMK_FSROOT "%s"},
	{Opt_fstransmute, SMK_FSTRANS "%s"},
	{Opt_error, NULL},
};

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#ifdef CONFIG_SECURITY_SMACK_BRINGUP
static char *smk_bu_mess[] = {
	"Bringup Error",	/* Unused */
	"Bringup",		/* SMACK_BRINGUP_ALLOW */
	"Unconfined Subject",	/* SMACK_UNCONFINED_SUBJECT */
	"Unconfined Object",	/* SMACK_UNCONFINED_OBJECT */
};

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static void smk_bu_mode(int mode, char *s)
{
	int i = 0;

	if (mode & MAY_READ)
		s[i++] = 'r';
	if (mode & MAY_WRITE)
		s[i++] = 'w';
	if (mode & MAY_EXEC)
		s[i++] = 'x';
	if (mode & MAY_APPEND)
		s[i++] = 'a';
	if (mode & MAY_TRANSMUTE)
		s[i++] = 't';
	if (mode & MAY_LOCK)
		s[i++] = 'l';
	if (i == 0)
		s[i++] = '-';
	s[i] = '\0';
}
#endif

#ifdef CONFIG_SECURITY_SMACK_BRINGUP
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static int smk_bu_note(char *note, struct smack_known *sskp,
		       struct smack_known *oskp, int mode, int rc)
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{
	char acc[SMK_NUM_ACCESS_TYPE + 1];

	if (rc <= 0)
		return rc;
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	if (rc > SMACK_UNCONFINED_OBJECT)
		rc = 0;
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	smk_bu_mode(mode, acc);
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	pr_info("Smack %s: (%s %s %s) %s\n", smk_bu_mess[rc],
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		sskp->smk_known, oskp->smk_known, acc, note);
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	return 0;
}
#else
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#define smk_bu_note(note, sskp, oskp, mode, RC) (RC)
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#endif

#ifdef CONFIG_SECURITY_SMACK_BRINGUP
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static int smk_bu_current(char *note, struct smack_known *oskp,
			  int mode, int rc)
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{
	struct task_smack *tsp = current_security();
	char acc[SMK_NUM_ACCESS_TYPE + 1];

	if (rc <= 0)
		return rc;
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	if (rc > SMACK_UNCONFINED_OBJECT)
		rc = 0;
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	smk_bu_mode(mode, acc);
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	pr_info("Smack %s: (%s %s %s) %s %s\n", smk_bu_mess[rc],
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		tsp->smk_task->smk_known, oskp->smk_known,
		acc, current->comm, note);
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	return 0;
}
#else
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#define smk_bu_current(note, oskp, mode, RC) (RC)
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#endif

#ifdef CONFIG_SECURITY_SMACK_BRINGUP
static int smk_bu_task(struct task_struct *otp, int mode, int rc)
{
	struct task_smack *tsp = current_security();
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	struct smack_known *smk_task = smk_of_task_struct(otp);
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	char acc[SMK_NUM_ACCESS_TYPE + 1];

	if (rc <= 0)
		return rc;
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	if (rc > SMACK_UNCONFINED_OBJECT)
		rc = 0;
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	smk_bu_mode(mode, acc);
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	pr_info("Smack %s: (%s %s %s) %s to %s\n", smk_bu_mess[rc],
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		tsp->smk_task->smk_known, smk_task->smk_known, acc,
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		current->comm, otp->comm);
	return 0;
}
#else
#define smk_bu_task(otp, mode, RC) (RC)
#endif

#ifdef CONFIG_SECURITY_SMACK_BRINGUP
static int smk_bu_inode(struct inode *inode, int mode, int rc)
{
	struct task_smack *tsp = current_security();
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	struct inode_smack *isp = inode->i_security;
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	char acc[SMK_NUM_ACCESS_TYPE + 1];

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	if (isp->smk_flags & SMK_INODE_IMPURE)
		pr_info("Smack Unconfined Corruption: inode=(%s %ld) %s\n",
			inode->i_sb->s_id, inode->i_ino, current->comm);

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	if (rc <= 0)
		return rc;
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	if (rc > SMACK_UNCONFINED_OBJECT)
		rc = 0;
	if (rc == SMACK_UNCONFINED_SUBJECT &&
	    (mode & (MAY_WRITE | MAY_APPEND)))
		isp->smk_flags |= SMK_INODE_IMPURE;
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	smk_bu_mode(mode, acc);
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	pr_info("Smack %s: (%s %s %s) inode=(%s %ld) %s\n", smk_bu_mess[rc],
		tsp->smk_task->smk_known, isp->smk_inode->smk_known, acc,
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		inode->i_sb->s_id, inode->i_ino, current->comm);
	return 0;
}
#else
#define smk_bu_inode(inode, mode, RC) (RC)
#endif

#ifdef CONFIG_SECURITY_SMACK_BRINGUP
static int smk_bu_file(struct file *file, int mode, int rc)
{
	struct task_smack *tsp = current_security();
	struct smack_known *sskp = tsp->smk_task;
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	struct inode *inode = file_inode(file);
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	struct inode_smack *isp = inode->i_security;
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	char acc[SMK_NUM_ACCESS_TYPE + 1];

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	if (isp->smk_flags & SMK_INODE_IMPURE)
		pr_info("Smack Unconfined Corruption: inode=(%s %ld) %s\n",
			inode->i_sb->s_id, inode->i_ino, current->comm);

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	if (rc <= 0)
		return rc;
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	if (rc > SMACK_UNCONFINED_OBJECT)
		rc = 0;
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	smk_bu_mode(mode, acc);
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	pr_info("Smack %s: (%s %s %s) file=(%s %ld %pD) %s\n", smk_bu_mess[rc],
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		sskp->smk_known, smk_of_inode(inode)->smk_known, acc,
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		inode->i_sb->s_id, inode->i_ino, file,
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		current->comm);
	return 0;
}
#else
#define smk_bu_file(file, mode, RC) (RC)
#endif

#ifdef CONFIG_SECURITY_SMACK_BRINGUP
static int smk_bu_credfile(const struct cred *cred, struct file *file,
				int mode, int rc)
{
	struct task_smack *tsp = cred->security;
	struct smack_known *sskp = tsp->smk_task;
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	struct inode *inode = file_inode(file);
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	struct inode_smack *isp = inode->i_security;
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	char acc[SMK_NUM_ACCESS_TYPE + 1];

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	if (isp->smk_flags & SMK_INODE_IMPURE)
		pr_info("Smack Unconfined Corruption: inode=(%s %ld) %s\n",
			inode->i_sb->s_id, inode->i_ino, current->comm);

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	if (rc <= 0)
		return rc;
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	if (rc > SMACK_UNCONFINED_OBJECT)
		rc = 0;
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	smk_bu_mode(mode, acc);
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	pr_info("Smack %s: (%s %s %s) file=(%s %ld %pD) %s\n", smk_bu_mess[rc],
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		sskp->smk_known, smk_of_inode(inode)->smk_known, acc,
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		inode->i_sb->s_id, inode->i_ino, file,
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		current->comm);
	return 0;
}
#else
#define smk_bu_credfile(cred, file, mode, RC) (RC)
#endif

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/**
 * smk_fetch - Fetch the smack label from a file.
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 * @name: type of the label (attribute)
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 * @ip: a pointer to the inode
 * @dp: a pointer to the dentry
 *
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 * Returns a pointer to the master list entry for the Smack label,
 * NULL if there was no label to fetch, or an error code.
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 */
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static struct smack_known *smk_fetch(const char *name, struct inode *ip,
					struct dentry *dp)
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{
	int rc;
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	char *buffer;
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	struct smack_known *skp = NULL;
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	if (!(ip->i_opflags & IOP_XATTR))
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		return ERR_PTR(-EOPNOTSUPP);
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	buffer = kzalloc(SMK_LONGLABEL, GFP_KERNEL);
	if (buffer == NULL)
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		return ERR_PTR(-ENOMEM);
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	rc = __vfs_getxattr(dp, ip, name, buffer, SMK_LONGLABEL);
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	if (rc < 0)
		skp = ERR_PTR(rc);
	else if (rc == 0)
		skp = NULL;
	else
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		skp = smk_import_entry(buffer, rc);
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	kfree(buffer);

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	return skp;
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}

/**
 * new_inode_smack - allocate an inode security blob
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 * @skp: a pointer to the Smack label entry to use in the blob
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 *
 * Returns the new blob or NULL if there's no memory available
 */
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static struct inode_smack *new_inode_smack(struct smack_known *skp)
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{
	struct inode_smack *isp;

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	isp = kmem_cache_zalloc(smack_inode_cache, GFP_NOFS);
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	if (isp == NULL)
		return NULL;

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	isp->smk_inode = skp;
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	isp->smk_flags = 0;
	mutex_init(&isp->smk_lock);

	return isp;
}

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/**
 * new_task_smack - allocate a task security blob
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 * @task: a pointer to the Smack label for the running task
 * @forked: a pointer to the Smack label for the forked task
 * @gfp: type of the memory for the allocation
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 *
 * Returns the new blob or NULL if there's no memory available
 */
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static struct task_smack *new_task_smack(struct smack_known *task,
					struct smack_known *forked, gfp_t gfp)
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{
	struct task_smack *tsp;

	tsp = kzalloc(sizeof(struct task_smack), gfp);
	if (tsp == NULL)
		return NULL;

	tsp->smk_task = task;
	tsp->smk_forked = forked;
	INIT_LIST_HEAD(&tsp->smk_rules);
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	INIT_LIST_HEAD(&tsp->smk_relabel);
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	mutex_init(&tsp->smk_rules_lock);

	return tsp;
}

/**
 * smk_copy_rules - copy a rule set
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 * @nhead: new rules header pointer
 * @ohead: old rules header pointer
 * @gfp: type of the memory for the allocation
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 *
 * Returns 0 on success, -ENOMEM on error
 */
static int smk_copy_rules(struct list_head *nhead, struct list_head *ohead,
				gfp_t gfp)
{
	struct smack_rule *nrp;
	struct smack_rule *orp;
	int rc = 0;

	list_for_each_entry_rcu(orp, ohead, list) {
		nrp = kzalloc(sizeof(struct smack_rule), gfp);
		if (nrp == NULL) {
			rc = -ENOMEM;
			break;
		}
		*nrp = *orp;
		list_add_rcu(&nrp->list, nhead);
	}
	return rc;
}

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/**
 * smk_copy_relabel - copy smk_relabel labels list
 * @nhead: new rules header pointer
 * @ohead: old rules header pointer
 * @gfp: type of the memory for the allocation
 *
 * Returns 0 on success, -ENOMEM on error
 */
static int smk_copy_relabel(struct list_head *nhead, struct list_head *ohead,
				gfp_t gfp)
{
	struct smack_known_list_elem *nklep;
	struct smack_known_list_elem *oklep;

	list_for_each_entry(oklep, ohead, list) {
		nklep = kzalloc(sizeof(struct smack_known_list_elem), gfp);
		if (nklep == NULL) {
			smk_destroy_label_list(nhead);
			return -ENOMEM;
		}
		nklep->smk_label = oklep->smk_label;
		list_add(&nklep->list, nhead);
	}

	return 0;
}

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/**
 * smk_ptrace_mode - helper function for converting PTRACE_MODE_* into MAY_*
 * @mode - input mode in form of PTRACE_MODE_*
 *
 * Returns a converted MAY_* mode usable by smack rules
 */
static inline unsigned int smk_ptrace_mode(unsigned int mode)
{
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	if (mode & PTRACE_MODE_ATTACH)
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		return MAY_READWRITE;
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	if (mode & PTRACE_MODE_READ)
		return MAY_READ;
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	return 0;
}

/**
 * smk_ptrace_rule_check - helper for ptrace access
 * @tracer: tracer process
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 * @tracee_known: label entry of the process that's about to be traced
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 * @mode: ptrace attachment mode (PTRACE_MODE_*)
 * @func: name of the function that called us, used for audit
 *
 * Returns 0 on access granted, -error on error
 */
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static int smk_ptrace_rule_check(struct task_struct *tracer,
				 struct smack_known *tracee_known,
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				 unsigned int mode, const char *func)
{
	int rc;
	struct smk_audit_info ad, *saip = NULL;
	struct task_smack *tsp;
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	struct smack_known *tracer_known;
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	if ((mode & PTRACE_MODE_NOAUDIT) == 0) {
		smk_ad_init(&ad, func, LSM_AUDIT_DATA_TASK);
		smk_ad_setfield_u_tsk(&ad, tracer);
		saip = &ad;
	}

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	rcu_read_lock();
	tsp = __task_cred(tracer)->security;
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	tracer_known = smk_of_task(tsp);
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	if ((mode & PTRACE_MODE_ATTACH) &&
	    (smack_ptrace_rule == SMACK_PTRACE_EXACT ||
	     smack_ptrace_rule == SMACK_PTRACE_DRACONIAN)) {
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		if (tracer_known->smk_known == tracee_known->smk_known)
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			rc = 0;
		else if (smack_ptrace_rule == SMACK_PTRACE_DRACONIAN)
			rc = -EACCES;
		else if (capable(CAP_SYS_PTRACE))
			rc = 0;
		else
			rc = -EACCES;

		if (saip)
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			smack_log(tracer_known->smk_known,
				  tracee_known->smk_known,
				  0, rc, saip);
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		rcu_read_unlock();
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		return rc;
	}

	/* In case of rule==SMACK_PTRACE_DEFAULT or mode==PTRACE_MODE_READ */
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	rc = smk_tskacc(tsp, tracee_known, smk_ptrace_mode(mode), saip);
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	rcu_read_unlock();
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	return rc;
}

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/*
 * LSM hooks.
 * We he, that is fun!
 */

/**
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 * smack_ptrace_access_check - Smack approval on PTRACE_ATTACH
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 * @ctp: child task pointer
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 * @mode: ptrace attachment mode (PTRACE_MODE_*)
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 *
 * Returns 0 if access is OK, an error code otherwise
 *
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 * Do the capability checks.
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 */
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static int smack_ptrace_access_check(struct task_struct *ctp, unsigned int mode)
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{
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	struct smack_known *skp;
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	skp = smk_of_task_struct(ctp);
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	return smk_ptrace_rule_check(current, skp, mode, __func__);
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}

/**
 * smack_ptrace_traceme - Smack approval on PTRACE_TRACEME
 * @ptp: parent task pointer
 *
 * Returns 0 if access is OK, an error code otherwise
 *
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 * Do the capability checks, and require PTRACE_MODE_ATTACH.
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 */
static int smack_ptrace_traceme(struct task_struct *ptp)
{
	int rc;
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	struct smack_known *skp;
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	skp = smk_of_task(current_security());
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	rc = smk_ptrace_rule_check(ptp, skp, PTRACE_MODE_ATTACH, __func__);
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	return rc;
}

/**
 * smack_syslog - Smack approval on syslog
 * @type: message type
 *
 * Returns 0 on success, error code otherwise.
 */
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static int smack_syslog(int typefrom_file)
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{
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	int rc = 0;
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	struct smack_known *skp = smk_of_current();
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	if (smack_privileged(CAP_MAC_OVERRIDE))
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		return 0;

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	if (smack_syslog_label != NULL && smack_syslog_label != skp)
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		rc = -EACCES;

	return rc;
}


/*
 * Superblock Hooks.
 */

/**
 * smack_sb_alloc_security - allocate a superblock blob
 * @sb: the superblock getting the blob
 *
 * Returns 0 on success or -ENOMEM on error.
 */
static int smack_sb_alloc_security(struct super_block *sb)
{
	struct superblock_smack *sbsp;

	sbsp = kzalloc(sizeof(struct superblock_smack), GFP_KERNEL);

	if (sbsp == NULL)
		return -ENOMEM;

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	sbsp->smk_root = &smack_known_floor;
	sbsp->smk_default = &smack_known_floor;
	sbsp->smk_floor = &smack_known_floor;
	sbsp->smk_hat = &smack_known_hat;
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	/*
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	 * SMK_SB_INITIALIZED will be zero from kzalloc.
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	 */
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	sb->s_security = sbsp;

	return 0;
}

/**
 * smack_sb_free_security - free a superblock blob
 * @sb: the superblock getting the blob
 *
 */
static void smack_sb_free_security(struct super_block *sb)
{
	kfree(sb->s_security);
	sb->s_security = NULL;
}

/**
 * smack_sb_copy_data - copy mount options data for processing
 * @orig: where to start
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 * @smackopts: mount options string
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 *
 * Returns 0 on success or -ENOMEM on error.
 *
 * Copy the Smack specific mount options out of the mount
 * options list.
 */
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static int smack_sb_copy_data(char *orig, char *smackopts)
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{
	char *cp, *commap, *otheropts, *dp;

	otheropts = (char *)get_zeroed_page(GFP_KERNEL);
	if (otheropts == NULL)
		return -ENOMEM;

	for (cp = orig, commap = orig; commap != NULL; cp = commap + 1) {
		if (strstr(cp, SMK_FSDEFAULT) == cp)
			dp = smackopts;
		else if (strstr(cp, SMK_FSFLOOR) == cp)
			dp = smackopts;
		else if (strstr(cp, SMK_FSHAT) == cp)
			dp = smackopts;
		else if (strstr(cp, SMK_FSROOT) == cp)
			dp = smackopts;
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		else if (strstr(cp, SMK_FSTRANS) == cp)
			dp = smackopts;
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		else
			dp = otheropts;

		commap = strchr(cp, ',');
		if (commap != NULL)
			*commap = '\0';

		if (*dp != '\0')
			strcat(dp, ",");
		strcat(dp, cp);
	}

	strcpy(orig, otheropts);
	free_page((unsigned long)otheropts);

	return 0;
}

/**
615 616 617 618 619 620 621 622 623 624 625 626
 * smack_parse_opts_str - parse Smack specific mount options
 * @options: mount options string
 * @opts: where to store converted mount opts
 *
 * Returns 0 on success or -ENOMEM on error.
 *
 * converts Smack specific mount options to generic security option format
 */
static int smack_parse_opts_str(char *options,
		struct security_mnt_opts *opts)
{
	char *p;
627 628 629 630 631 632 633 634
	char *fsdefault = NULL;
	char *fsfloor = NULL;
	char *fshat = NULL;
	char *fsroot = NULL;
	char *fstransmute = NULL;
	int rc = -ENOMEM;
	int num_mnt_opts = 0;
	int token;
635 636 637 638 639 640 641 642 643 644 645 646

	opts->num_mnt_opts = 0;

	if (!options)
		return 0;

	while ((p = strsep(&options, ",")) != NULL) {
		substring_t args[MAX_OPT_ARGS];

		if (!*p)
			continue;

647
		token = match_token(p, smk_mount_tokens, args);
648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691

		switch (token) {
		case Opt_fsdefault:
			if (fsdefault)
				goto out_opt_err;
			fsdefault = match_strdup(&args[0]);
			if (!fsdefault)
				goto out_err;
			break;
		case Opt_fsfloor:
			if (fsfloor)
				goto out_opt_err;
			fsfloor = match_strdup(&args[0]);
			if (!fsfloor)
				goto out_err;
			break;
		case Opt_fshat:
			if (fshat)
				goto out_opt_err;
			fshat = match_strdup(&args[0]);
			if (!fshat)
				goto out_err;
			break;
		case Opt_fsroot:
			if (fsroot)
				goto out_opt_err;
			fsroot = match_strdup(&args[0]);
			if (!fsroot)
				goto out_err;
			break;
		case Opt_fstransmute:
			if (fstransmute)
				goto out_opt_err;
			fstransmute = match_strdup(&args[0]);
			if (!fstransmute)
				goto out_err;
			break;
		default:
			rc = -EINVAL;
			pr_warn("Smack:  unknown mount option\n");
			goto out_err;
		}
	}

692
	opts->mnt_opts = kcalloc(NUM_SMK_MNT_OPTS, sizeof(char *), GFP_KERNEL);
693 694 695 696
	if (!opts->mnt_opts)
		goto out_err;

	opts->mnt_opts_flags = kcalloc(NUM_SMK_MNT_OPTS, sizeof(int),
697
			GFP_KERNEL);
698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741
	if (!opts->mnt_opts_flags) {
		kfree(opts->mnt_opts);
		goto out_err;
	}

	if (fsdefault) {
		opts->mnt_opts[num_mnt_opts] = fsdefault;
		opts->mnt_opts_flags[num_mnt_opts++] = FSDEFAULT_MNT;
	}
	if (fsfloor) {
		opts->mnt_opts[num_mnt_opts] = fsfloor;
		opts->mnt_opts_flags[num_mnt_opts++] = FSFLOOR_MNT;
	}
	if (fshat) {
		opts->mnt_opts[num_mnt_opts] = fshat;
		opts->mnt_opts_flags[num_mnt_opts++] = FSHAT_MNT;
	}
	if (fsroot) {
		opts->mnt_opts[num_mnt_opts] = fsroot;
		opts->mnt_opts_flags[num_mnt_opts++] = FSROOT_MNT;
	}
	if (fstransmute) {
		opts->mnt_opts[num_mnt_opts] = fstransmute;
		opts->mnt_opts_flags[num_mnt_opts++] = FSTRANS_MNT;
	}

	opts->num_mnt_opts = num_mnt_opts;
	return 0;

out_opt_err:
	rc = -EINVAL;
	pr_warn("Smack: duplicate mount options\n");

out_err:
	kfree(fsdefault);
	kfree(fsfloor);
	kfree(fshat);
	kfree(fsroot);
	kfree(fstransmute);
	return rc;
}

/**
 * smack_set_mnt_opts - set Smack specific mount options
742
 * @sb: the file system superblock
743 744 745
 * @opts: Smack mount options
 * @kern_flags: mount option from kernel space or user space
 * @set_kern_flags: where to store converted mount opts
746 747
 *
 * Returns 0 on success, an error code on failure
748 749 750
 *
 * Allow filesystems with binary mount data to explicitly set Smack mount
 * labels.
751
 */
752 753 754 755
static int smack_set_mnt_opts(struct super_block *sb,
		struct security_mnt_opts *opts,
		unsigned long kern_flags,
		unsigned long *set_kern_flags)
756 757
{
	struct dentry *root = sb->s_root;
758
	struct inode *inode = d_backing_inode(root);
759 760
	struct superblock_smack *sp = sb->s_security;
	struct inode_smack *isp;
761
	struct smack_known *skp;
762 763
	int i;
	int num_opts = opts->num_mnt_opts;
764
	int transmute = 0;
765

766
	if (sp->smk_flags & SMK_SB_INITIALIZED)
767
		return 0;
768

769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793
	if (!smack_privileged(CAP_MAC_ADMIN)) {
		/*
		 * Unprivileged mounts don't get to specify Smack values.
		 */
		if (num_opts)
			return -EPERM;
		/*
		 * Unprivileged mounts get root and default from the caller.
		 */
		skp = smk_of_current();
		sp->smk_root = skp;
		sp->smk_default = skp;
		/*
		 * For a handful of fs types with no user-controlled
		 * backing store it's okay to trust security labels
		 * in the filesystem. The rest are untrusted.
		 */
		if (sb->s_user_ns != &init_user_ns &&
		    sb->s_magic != SYSFS_MAGIC && sb->s_magic != TMPFS_MAGIC &&
		    sb->s_magic != RAMFS_MAGIC) {
			transmute = 1;
			sp->smk_flags |= SMK_SB_UNTRUSTED;
		}
	}

794
	sp->smk_flags |= SMK_SB_INITIALIZED;
795

796 797 798 799
	for (i = 0; i < num_opts; i++) {
		switch (opts->mnt_opts_flags[i]) {
		case FSDEFAULT_MNT:
			skp = smk_import_entry(opts->mnt_opts[i], 0);
800 801
			if (IS_ERR(skp))
				return PTR_ERR(skp);
802 803 804 805
			sp->smk_default = skp;
			break;
		case FSFLOOR_MNT:
			skp = smk_import_entry(opts->mnt_opts[i], 0);
806 807 808
			if (IS_ERR(skp))
				return PTR_ERR(skp);
			sp->smk_floor = skp;
809 810 811
			break;
		case FSHAT_MNT:
			skp = smk_import_entry(opts->mnt_opts[i], 0);
812 813
			if (IS_ERR(skp))
				return PTR_ERR(skp);
814 815 816 817
			sp->smk_hat = skp;
			break;
		case FSROOT_MNT:
			skp = smk_import_entry(opts->mnt_opts[i], 0);
818 819 820
			if (IS_ERR(skp))
				return PTR_ERR(skp);
			sp->smk_root = skp;
821 822 823
			break;
		case FSTRANS_MNT:
			skp = smk_import_entry(opts->mnt_opts[i], 0);
824 825 826 827
			if (IS_ERR(skp))
				return PTR_ERR(skp);
			sp->smk_root = skp;
			transmute = 1;
828 829 830
			break;
		default:
			break;
831 832 833 834 835 836 837
		}
	}

	/*
	 * Initialize the root inode.
	 */
	isp = inode->i_security;
838 839 840 841 842
	if (isp == NULL) {
		isp = new_inode_smack(sp->smk_root);
		if (isp == NULL)
			return -ENOMEM;
		inode->i_security = isp;
843
	} else
844 845
		isp->smk_inode = sp->smk_root;

846 847 848
	if (transmute)
		isp->smk_flags |= SMK_INODE_TRANSMUTE;

849 850 851
	return 0;
}

852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882
/**
 * smack_sb_kern_mount - Smack specific mount processing
 * @sb: the file system superblock
 * @flags: the mount flags
 * @data: the smack mount options
 *
 * Returns 0 on success, an error code on failure
 */
static int smack_sb_kern_mount(struct super_block *sb, int flags, void *data)
{
	int rc = 0;
	char *options = data;
	struct security_mnt_opts opts;

	security_init_mnt_opts(&opts);

	if (!options)
		goto out;

	rc = smack_parse_opts_str(options, &opts);
	if (rc)
		goto out_err;

out:
	rc = smack_set_mnt_opts(sb, &opts, 0, NULL);

out_err:
	security_free_mnt_opts(&opts);
	return rc;
}

883 884 885 886 887 888 889 890 891 892
/**
 * smack_sb_statfs - Smack check on statfs
 * @dentry: identifies the file system in question
 *
 * Returns 0 if current can read the floor of the filesystem,
 * and error code otherwise
 */
static int smack_sb_statfs(struct dentry *dentry)
{
	struct superblock_smack *sbp = dentry->d_sb->s_security;
E
Etienne Basset 已提交
893 894 895
	int rc;
	struct smk_audit_info ad;

896
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
E
Etienne Basset 已提交
897
	smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
898

E
Etienne Basset 已提交
899
	rc = smk_curacc(sbp->smk_floor, MAY_READ, &ad);
C
Casey Schaufler 已提交
900
	rc = smk_bu_current("statfs", sbp->smk_floor, MAY_READ, rc);
E
Etienne Basset 已提交
901
	return rc;
902 903
}

904 905 906 907
/*
 * BPRM hooks
 */

C
Casey Schaufler 已提交
908 909 910 911
/**
 * smack_bprm_set_creds - set creds for exec
 * @bprm: the exec information
 *
912
 * Returns 0 if it gets a blob, -EPERM if exec forbidden and -ENOMEM otherwise
C
Casey Schaufler 已提交
913
 */
914 915
static int smack_bprm_set_creds(struct linux_binprm *bprm)
{
A
Al Viro 已提交
916
	struct inode *inode = file_inode(bprm->file);
917
	struct task_smack *bsp = bprm->cred->security;
918
	struct inode_smack *isp;
919
	struct superblock_smack *sbsp;
920 921 922 923 924
	int rc;

	if (bprm->cred_prepared)
		return 0;

925 926
	isp = inode->i_security;
	if (isp->smk_task == NULL || isp->smk_task == bsp->smk_task)
927 928
		return 0;

929 930 931 932 933
	sbsp = inode->i_sb->s_security;
	if ((sbsp->smk_flags & SMK_SB_UNTRUSTED) &&
	    isp->smk_task != sbsp->smk_root)
		return 0;

934 935 936 937 938 939 940 941
	if (bprm->unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
		struct task_struct *tracer;
		rc = 0;

		rcu_read_lock();
		tracer = ptrace_parent(current);
		if (likely(tracer != NULL))
			rc = smk_ptrace_rule_check(tracer,
942
						   isp->smk_task,
943 944 945 946 947 948 949
						   PTRACE_MODE_ATTACH,
						   __func__);
		rcu_read_unlock();

		if (rc != 0)
			return rc;
	} else if (bprm->unsafe)
950
		return -EPERM;
951

952 953
	bsp->smk_task = isp->smk_task;
	bprm->per_clear |= PER_CLEAR_ON_SETID;
954

955 956
	return 0;
}
957

958 959 960 961 962 963 964 965 966
/**
 * smack_bprm_committing_creds - Prepare to install the new credentials
 * from bprm.
 *
 * @bprm: binprm for exec
 */
static void smack_bprm_committing_creds(struct linux_binprm *bprm)
{
	struct task_smack *bsp = bprm->cred->security;
967

968 969 970 971 972 973 974 975 976 977 978 979 980 981
	if (bsp->smk_task != bsp->smk_forked)
		current->pdeath_signal = 0;
}

/**
 * smack_bprm_secureexec - Return the decision to use secureexec.
 * @bprm: binprm for exec
 *
 * Returns 0 on success.
 */
static int smack_bprm_secureexec(struct linux_binprm *bprm)
{
	struct task_smack *tsp = current_security();

C
Casey Schaufler 已提交
982 983
	if (tsp->smk_task != tsp->smk_forked)
		return 1;
984

C
Casey Schaufler 已提交
985
	return 0;
986 987
}

988 989 990 991 992 993
/*
 * Inode hooks
 */

/**
 * smack_inode_alloc_security - allocate an inode blob
994
 * @inode: the inode in need of a blob
995 996 997 998 999
 *
 * Returns 0 if it gets a blob, -ENOMEM otherwise
 */
static int smack_inode_alloc_security(struct inode *inode)
{
1000 1001
	struct smack_known *skp = smk_of_current();

1002
	inode->i_security = new_inode_smack(skp);
1003 1004 1005 1006 1007 1008
	if (inode->i_security == NULL)
		return -ENOMEM;
	return 0;
}

/**
1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024
 * smack_inode_free_rcu - Free inode_smack blob from cache
 * @head: the rcu_head for getting inode_smack pointer
 *
 *  Call back function called from call_rcu() to free
 *  the i_security blob pointer in inode
 */
static void smack_inode_free_rcu(struct rcu_head *head)
{
	struct inode_smack *issp;

	issp = container_of(head, struct inode_smack, smk_rcu);
	kmem_cache_free(smack_inode_cache, issp);
}

/**
 * smack_inode_free_security - free an inode blob using call_rcu()
1025
 * @inode: the inode with a blob
1026
 *
1027
 * Clears the blob pointer in inode using RCU
1028 1029 1030
 */
static void smack_inode_free_security(struct inode *inode)
{
1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041
	struct inode_smack *issp = inode->i_security;

	/*
	 * The inode may still be referenced in a path walk and
	 * a call to smack_inode_permission() can be made
	 * after smack_inode_free_security() is called.
	 * To avoid race condition free the i_security via RCU
	 * and leave the current inode->i_security pointer intact.
	 * The inode will be freed after the RCU grace period too.
	 */
	call_rcu(&issp->smk_rcu, smack_inode_free_rcu);
1042 1043 1044 1045
}

/**
 * smack_inode_init_security - copy out the smack from an inode
1046 1047
 * @inode: the newly created inode
 * @dir: containing directory object
1048
 * @qstr: unused
1049 1050 1051 1052 1053 1054 1055
 * @name: where to put the attribute name
 * @value: where to put the attribute value
 * @len: where to put the length of the attribute
 *
 * Returns 0 if it all works out, -ENOMEM if there's no memory
 */
static int smack_inode_init_security(struct inode *inode, struct inode *dir,
1056
				     const struct qstr *qstr, const char **name,
1057
				     void **value, size_t *len)
1058
{
C
Casey Schaufler 已提交
1059
	struct inode_smack *issp = inode->i_security;
1060
	struct smack_known *skp = smk_of_current();
1061 1062
	struct smack_known *isp = smk_of_inode(inode);
	struct smack_known *dsp = smk_of_inode(dir);
1063
	int may;
1064

1065 1066
	if (name)
		*name = XATTR_SMACK_SUFFIX;
1067

1068
	if (value && len) {
1069
		rcu_read_lock();
1070 1071
		may = smk_access_entry(skp->smk_known, dsp->smk_known,
				       &skp->smk_rules);
1072
		rcu_read_unlock();
1073 1074 1075 1076 1077

		/*
		 * If the access rule allows transmutation and
		 * the directory requests transmutation then
		 * by all means transmute.
C
Casey Schaufler 已提交
1078
		 * Mark the inode as changed.
1079
		 */
1080
		if (may > 0 && ((may & MAY_TRANSMUTE) != 0) &&
C
Casey Schaufler 已提交
1081
		    smk_inode_transmutable(dir)) {
1082
			isp = dsp;
C
Casey Schaufler 已提交
1083 1084
			issp->smk_flags |= SMK_INODE_CHANGED;
		}
1085

1086
		*value = kstrdup(isp->smk_known, GFP_NOFS);
1087 1088 1089
		if (*value == NULL)
			return -ENOMEM;

1090
		*len = strlen(isp->smk_known);
1091
	}
1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106

	return 0;
}

/**
 * smack_inode_link - Smack check on link
 * @old_dentry: the existing object
 * @dir: unused
 * @new_dentry: the new object
 *
 * Returns 0 if access is permitted, an error code otherwise
 */
static int smack_inode_link(struct dentry *old_dentry, struct inode *dir,
			    struct dentry *new_dentry)
{
1107
	struct smack_known *isp;
E
Etienne Basset 已提交
1108 1109 1110
	struct smk_audit_info ad;
	int rc;

1111
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
E
Etienne Basset 已提交
1112
	smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
1113

1114
	isp = smk_of_inode(d_backing_inode(old_dentry));
E
Etienne Basset 已提交
1115
	rc = smk_curacc(isp, MAY_WRITE, &ad);
1116
	rc = smk_bu_inode(d_backing_inode(old_dentry), MAY_WRITE, rc);
1117

1118
	if (rc == 0 && d_is_positive(new_dentry)) {
1119
		isp = smk_of_inode(d_backing_inode(new_dentry));
E
Etienne Basset 已提交
1120 1121
		smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
		rc = smk_curacc(isp, MAY_WRITE, &ad);
1122
		rc = smk_bu_inode(d_backing_inode(new_dentry), MAY_WRITE, rc);
1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137
	}

	return rc;
}

/**
 * smack_inode_unlink - Smack check on inode deletion
 * @dir: containing directory object
 * @dentry: file to unlink
 *
 * Returns 0 if current can write the containing directory
 * and the object, error code otherwise
 */
static int smack_inode_unlink(struct inode *dir, struct dentry *dentry)
{
1138
	struct inode *ip = d_backing_inode(dentry);
E
Etienne Basset 已提交
1139
	struct smk_audit_info ad;
1140 1141
	int rc;

1142
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
E
Etienne Basset 已提交
1143 1144
	smk_ad_setfield_u_fs_path_dentry(&ad, dentry);

1145 1146 1147
	/*
	 * You need write access to the thing you're unlinking
	 */
E
Etienne Basset 已提交
1148
	rc = smk_curacc(smk_of_inode(ip), MAY_WRITE, &ad);
C
Casey Schaufler 已提交
1149
	rc = smk_bu_inode(ip, MAY_WRITE, rc);
E
Etienne Basset 已提交
1150
	if (rc == 0) {
1151 1152 1153
		/*
		 * You also need write access to the containing directory
		 */
1154
		smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
E
Etienne Basset 已提交
1155 1156
		smk_ad_setfield_u_fs_inode(&ad, dir);
		rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad);
C
Casey Schaufler 已提交
1157
		rc = smk_bu_inode(dir, MAY_WRITE, rc);
E
Etienne Basset 已提交
1158
	}
1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171
	return rc;
}

/**
 * smack_inode_rmdir - Smack check on directory deletion
 * @dir: containing directory object
 * @dentry: directory to unlink
 *
 * Returns 0 if current can write the containing directory
 * and the directory, error code otherwise
 */
static int smack_inode_rmdir(struct inode *dir, struct dentry *dentry)
{
E
Etienne Basset 已提交
1172
	struct smk_audit_info ad;
1173 1174
	int rc;

1175
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
E
Etienne Basset 已提交
1176 1177
	smk_ad_setfield_u_fs_path_dentry(&ad, dentry);

1178 1179 1180
	/*
	 * You need write access to the thing you're removing
	 */
1181 1182
	rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
	rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
E
Etienne Basset 已提交
1183
	if (rc == 0) {
1184 1185 1186
		/*
		 * You also need write access to the containing directory
		 */
1187
		smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
E
Etienne Basset 已提交
1188 1189
		smk_ad_setfield_u_fs_inode(&ad, dir);
		rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad);
C
Casey Schaufler 已提交
1190
		rc = smk_bu_inode(dir, MAY_WRITE, rc);
E
Etienne Basset 已提交
1191
	}
1192 1193 1194 1195 1196 1197

	return rc;
}

/**
 * smack_inode_rename - Smack check on rename
1198 1199 1200 1201
 * @old_inode: unused
 * @old_dentry: the old object
 * @new_inode: unused
 * @new_dentry: the new object
1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213
 *
 * Read and write access is required on both the old and
 * new directories.
 *
 * Returns 0 if access is permitted, an error code otherwise
 */
static int smack_inode_rename(struct inode *old_inode,
			      struct dentry *old_dentry,
			      struct inode *new_inode,
			      struct dentry *new_dentry)
{
	int rc;
1214
	struct smack_known *isp;
E
Etienne Basset 已提交
1215 1216
	struct smk_audit_info ad;

1217
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
E
Etienne Basset 已提交
1218
	smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
1219

1220
	isp = smk_of_inode(d_backing_inode(old_dentry));
E
Etienne Basset 已提交
1221
	rc = smk_curacc(isp, MAY_READWRITE, &ad);
1222
	rc = smk_bu_inode(d_backing_inode(old_dentry), MAY_READWRITE, rc);
1223

1224
	if (rc == 0 && d_is_positive(new_dentry)) {
1225
		isp = smk_of_inode(d_backing_inode(new_dentry));
E
Etienne Basset 已提交
1226 1227
		smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
		rc = smk_curacc(isp, MAY_READWRITE, &ad);
1228
		rc = smk_bu_inode(d_backing_inode(new_dentry), MAY_READWRITE, rc);
1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241
	}
	return rc;
}

/**
 * smack_inode_permission - Smack version of permission()
 * @inode: the inode in question
 * @mask: the access requested
 *
 * This is the important Smack hook.
 *
 * Returns 0 if access is permitted, -EACCES otherwise
 */
1242
static int smack_inode_permission(struct inode *inode, int mask)
1243
{
1244
	struct superblock_smack *sbsp = inode->i_sb->s_security;
E
Etienne Basset 已提交
1245
	struct smk_audit_info ad;
1246
	int no_block = mask & MAY_NOT_BLOCK;
C
Casey Schaufler 已提交
1247
	int rc;
1248 1249

	mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
1250 1251 1252 1253 1254
	/*
	 * No permission to check. Existence test. Yup, it's there.
	 */
	if (mask == 0)
		return 0;
1255

1256 1257 1258 1259 1260
	if (sbsp->smk_flags & SMK_SB_UNTRUSTED) {
		if (smk_of_inode(inode) != sbsp->smk_root)
			return -EACCES;
	}

1261
	/* May be droppable after audit */
1262
	if (no_block)
1263
		return -ECHILD;
1264
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
E
Etienne Basset 已提交
1265
	smk_ad_setfield_u_fs_inode(&ad, inode);
C
Casey Schaufler 已提交
1266 1267 1268
	rc = smk_curacc(smk_of_inode(inode), mask, &ad);
	rc = smk_bu_inode(inode, mask, rc);
	return rc;
1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279
}

/**
 * smack_inode_setattr - Smack check for setting attributes
 * @dentry: the object
 * @iattr: for the force flag
 *
 * Returns 0 if access is permitted, an error code otherwise
 */
static int smack_inode_setattr(struct dentry *dentry, struct iattr *iattr)
{
E
Etienne Basset 已提交
1280
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
1281 1282
	int rc;

1283 1284 1285 1286 1287
	/*
	 * Need to allow for clearing the setuid bit.
	 */
	if (iattr->ia_valid & ATTR_FORCE)
		return 0;
1288
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
E
Etienne Basset 已提交
1289
	smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1290

1291 1292
	rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
	rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
C
Casey Schaufler 已提交
1293
	return rc;
1294 1295 1296 1297
}

/**
 * smack_inode_getattr - Smack check for getting attributes
1298
 * @mnt: vfsmount of the object
1299 1300 1301 1302
 * @dentry: the object
 *
 * Returns 0 if access is permitted, an error code otherwise
 */
1303
static int smack_inode_getattr(const struct path *path)
1304
{
E
Etienne Basset 已提交
1305
	struct smk_audit_info ad;
1306
	struct inode *inode = d_backing_inode(path->dentry);
C
Casey Schaufler 已提交
1307
	int rc;
E
Etienne Basset 已提交
1308

1309
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1310 1311 1312
	smk_ad_setfield_u_fs_path(&ad, *path);
	rc = smk_curacc(smk_of_inode(inode), MAY_READ, &ad);
	rc = smk_bu_inode(inode, MAY_READ, rc);
C
Casey Schaufler 已提交
1313
	return rc;
1314 1315 1316 1317 1318 1319
}

/**
 * smack_inode_setxattr - Smack check for setting xattrs
 * @dentry: the object
 * @name: name of the attribute
1320 1321
 * @value: value of the attribute
 * @size: size of the value
1322 1323 1324 1325 1326 1327
 * @flags: unused
 *
 * This protects the Smack attribute explicitly.
 *
 * Returns 0 if access is permitted, an error code otherwise
 */
1328 1329
static int smack_inode_setxattr(struct dentry *dentry, const char *name,
				const void *value, size_t size, int flags)
1330
{
E
Etienne Basset 已提交
1331
	struct smk_audit_info ad;
1332 1333 1334 1335
	struct smack_known *skp;
	int check_priv = 0;
	int check_import = 0;
	int check_star = 0;
1336
	int rc = 0;
1337

1338 1339 1340
	/*
	 * Check label validity here so import won't fail in post_setxattr
	 */
1341 1342
	if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
	    strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
1343 1344 1345 1346 1347 1348 1349 1350
	    strcmp(name, XATTR_NAME_SMACKIPOUT) == 0) {
		check_priv = 1;
		check_import = 1;
	} else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
		   strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
		check_priv = 1;
		check_import = 1;
		check_star = 1;
1351
	} else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) {
1352
		check_priv = 1;
1353 1354 1355
		if (size != TRANS_TRUE_SIZE ||
		    strncmp(value, TRANS_TRUE, TRANS_TRUE_SIZE) != 0)
			rc = -EINVAL;
1356 1357 1358
	} else
		rc = cap_inode_setxattr(dentry, name, value, size, flags);

1359 1360 1361 1362
	if (check_priv && !smack_privileged(CAP_MAC_ADMIN))
		rc = -EPERM;

	if (rc == 0 && check_import) {
1363
		skp = size ? smk_import_entry(value, size) : NULL;
1364 1365 1366
		if (IS_ERR(skp))
			rc = PTR_ERR(skp);
		else if (skp == NULL || (check_star &&
1367 1368 1369 1370
		    (skp == &smack_known_star || skp == &smack_known_web)))
			rc = -EINVAL;
	}

1371
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
E
Etienne Basset 已提交
1372 1373
	smk_ad_setfield_u_fs_path_dentry(&ad, dentry);

C
Casey Schaufler 已提交
1374
	if (rc == 0) {
1375 1376
		rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
		rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
C
Casey Schaufler 已提交
1377
	}
1378 1379

	return rc;
1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392
}

/**
 * smack_inode_post_setxattr - Apply the Smack update approved above
 * @dentry: object
 * @name: attribute name
 * @value: attribute value
 * @size: attribute size
 * @flags: unused
 *
 * Set the pointer in the inode blob to the entry found
 * in the master label list.
 */
1393 1394
static void smack_inode_post_setxattr(struct dentry *dentry, const char *name,
				      const void *value, size_t size, int flags)
1395
{
1396
	struct smack_known *skp;
1397
	struct inode_smack *isp = d_backing_inode(dentry)->i_security;
1398

1399 1400 1401 1402 1403
	if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) {
		isp->smk_flags |= SMK_INODE_TRANSMUTE;
		return;
	}

1404
	if (strcmp(name, XATTR_NAME_SMACK) == 0) {
1405
		skp = smk_import_entry(value, size);
1406
		if (!IS_ERR(skp))
1407
			isp->smk_inode = skp;
1408
	} else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0) {
1409
		skp = smk_import_entry(value, size);
1410
		if (!IS_ERR(skp))
1411
			isp->smk_task = skp;
1412
	} else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
1413
		skp = smk_import_entry(value, size);
1414
		if (!IS_ERR(skp))
1415 1416
			isp->smk_mmap = skp;
	}
1417 1418 1419 1420

	return;
}

C
Casey Schaufler 已提交
1421
/**
1422 1423 1424 1425 1426 1427
 * smack_inode_getxattr - Smack check on getxattr
 * @dentry: the object
 * @name: unused
 *
 * Returns 0 if access is permitted, an error code otherwise
 */
1428
static int smack_inode_getxattr(struct dentry *dentry, const char *name)
1429
{
E
Etienne Basset 已提交
1430
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
1431
	int rc;
E
Etienne Basset 已提交
1432

1433
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
E
Etienne Basset 已提交
1434 1435
	smk_ad_setfield_u_fs_path_dentry(&ad, dentry);

1436 1437
	rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_READ, &ad);
	rc = smk_bu_inode(d_backing_inode(dentry), MAY_READ, rc);
C
Casey Schaufler 已提交
1438
	return rc;
1439 1440
}

C
Casey Schaufler 已提交
1441
/**
1442 1443 1444 1445 1446 1447 1448 1449
 * smack_inode_removexattr - Smack check on removexattr
 * @dentry: the object
 * @name: name of the attribute
 *
 * Removing the Smack attribute requires CAP_MAC_ADMIN
 *
 * Returns 0 if access is permitted, an error code otherwise
 */
1450
static int smack_inode_removexattr(struct dentry *dentry, const char *name)
1451
{
1452
	struct inode_smack *isp;
E
Etienne Basset 已提交
1453
	struct smk_audit_info ad;
1454
	int rc = 0;
1455

1456 1457
	if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
	    strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
1458
	    strcmp(name, XATTR_NAME_SMACKIPOUT) == 0 ||
1459
	    strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
1460
	    strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0 ||
P
Pankaj Kumar 已提交
1461
	    strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
1462
		if (!smack_privileged(CAP_MAC_ADMIN))
1463 1464 1465 1466
			rc = -EPERM;
	} else
		rc = cap_inode_removexattr(dentry, name);

1467 1468 1469
	if (rc != 0)
		return rc;

1470
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
E
Etienne Basset 已提交
1471
	smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1472

1473 1474
	rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
	rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
1475 1476 1477
	if (rc != 0)
		return rc;

1478
	isp = d_backing_inode(dentry)->i_security;
1479 1480 1481 1482 1483
	/*
	 * Don't do anything special for these.
	 *	XATTR_NAME_SMACKIPIN
	 *	XATTR_NAME_SMACKIPOUT
	 */
J
José Bollo 已提交
1484
	if (strcmp(name, XATTR_NAME_SMACK) == 0) {
1485
		struct super_block *sbp = dentry->d_sb;
J
José Bollo 已提交
1486 1487 1488 1489
		struct superblock_smack *sbsp = sbp->s_security;

		isp->smk_inode = sbsp->smk_default;
	} else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0)
1490
		isp->smk_task = NULL;
1491
	else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0)
1492
		isp->smk_mmap = NULL;
1493 1494
	else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0)
		isp->smk_flags &= ~SMK_INODE_TRANSMUTE;
1495

1496
	return 0;
1497 1498 1499 1500 1501 1502 1503
}

/**
 * smack_inode_getsecurity - get smack xattrs
 * @inode: the object
 * @name: attribute name
 * @buffer: where to put the result
1504
 * @alloc: unused
1505 1506 1507
 *
 * Returns the size of the attribute or an error code
 */
1508
static int smack_inode_getsecurity(struct inode *inode,
1509 1510 1511 1512 1513 1514 1515
				   const char *name, void **buffer,
				   bool alloc)
{
	struct socket_smack *ssp;
	struct socket *sock;
	struct super_block *sbp;
	struct inode *ip = (struct inode *)inode;
1516
	struct smack_known *isp;
1517 1518 1519 1520 1521
	int ilen;
	int rc = 0;

	if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
		isp = smk_of_inode(inode);
1522 1523
		ilen = strlen(isp->smk_known);
		*buffer = isp->smk_known;
1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534
		return ilen;
	}

	/*
	 * The rest of the Smack xattrs are only on sockets.
	 */
	sbp = ip->i_sb;
	if (sbp->s_magic != SOCKFS_MAGIC)
		return -EOPNOTSUPP;

	sock = SOCKET_I(ip);
1535
	if (sock == NULL || sock->sk == NULL)
1536 1537 1538 1539 1540
		return -EOPNOTSUPP;

	ssp = sock->sk->sk_security;

	if (strcmp(name, XATTR_SMACK_IPIN) == 0)
1541
		isp = ssp->smk_in;
1542
	else if (strcmp(name, XATTR_SMACK_IPOUT) == 0)
1543
		isp = ssp->smk_out;
1544 1545 1546
	else
		return -EOPNOTSUPP;

1547
	ilen = strlen(isp->smk_known);
1548
	if (rc == 0) {
1549
		*buffer = isp->smk_known;
1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565
		rc = ilen;
	}

	return rc;
}


/**
 * smack_inode_listsecurity - list the Smack attributes
 * @inode: the object
 * @buffer: where they go
 * @buffer_size: size of buffer
 */
static int smack_inode_listsecurity(struct inode *inode, char *buffer,
				    size_t buffer_size)
{
1566
	int len = sizeof(XATTR_NAME_SMACK);
1567

1568
	if (buffer != NULL && len <= buffer_size)
1569
		memcpy(buffer, XATTR_NAME_SMACK, len);
1570 1571

	return len;
1572 1573
}

1574 1575 1576 1577 1578
/**
 * smack_inode_getsecid - Extract inode's security id
 * @inode: inode to extract the info from
 * @secid: where result will be saved
 */
1579
static void smack_inode_getsecid(struct inode *inode, u32 *secid)
1580 1581 1582
{
	struct inode_smack *isp = inode->i_security;

1583
	*secid = isp->smk_inode->smk_secid;
1584 1585
}

1586 1587 1588 1589
/*
 * File Hooks
 */

C
Casey Schaufler 已提交
1590 1591
/*
 * There is no smack_file_permission hook
1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607
 *
 * Should access checks be done on each read or write?
 * UNICOS and SELinux say yes.
 * Trusted Solaris, Trusted Irix, and just about everyone else says no.
 *
 * I'll say no for now. Smack does not do the frequent
 * label changing that SELinux does.
 */

/**
 * smack_file_alloc_security - assign a file security blob
 * @file: the object
 *
 * The security blob for a file is a pointer to the master
 * label list, so no allocation is done.
 *
C
Casey Schaufler 已提交
1608 1609 1610
 * f_security is the owner security information. It
 * isn't used on file access checks, it's for send_sigio.
 *
1611 1612 1613 1614
 * Returns 0
 */
static int smack_file_alloc_security(struct file *file)
{
1615 1616
	struct smack_known *skp = smk_of_current();

1617
	file->f_security = skp;
1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646
	return 0;
}

/**
 * smack_file_free_security - clear a file security blob
 * @file: the object
 *
 * The security blob for a file is a pointer to the master
 * label list, so no memory is freed.
 */
static void smack_file_free_security(struct file *file)
{
	file->f_security = NULL;
}

/**
 * smack_file_ioctl - Smack check on ioctls
 * @file: the object
 * @cmd: what to do
 * @arg: unused
 *
 * Relies heavily on the correct use of the ioctl command conventions.
 *
 * Returns 0 if allowed, error code otherwise
 */
static int smack_file_ioctl(struct file *file, unsigned int cmd,
			    unsigned long arg)
{
	int rc = 0;
E
Etienne Basset 已提交
1647
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
1648
	struct inode *inode = file_inode(file);
E
Etienne Basset 已提交
1649

1650
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
E
Etienne Basset 已提交
1651
	smk_ad_setfield_u_fs_path(&ad, file->f_path);
1652

C
Casey Schaufler 已提交
1653
	if (_IOC_DIR(cmd) & _IOC_WRITE) {
C
Casey Schaufler 已提交
1654
		rc = smk_curacc(smk_of_inode(inode), MAY_WRITE, &ad);
C
Casey Schaufler 已提交
1655 1656
		rc = smk_bu_file(file, MAY_WRITE, rc);
	}
1657

C
Casey Schaufler 已提交
1658
	if (rc == 0 && (_IOC_DIR(cmd) & _IOC_READ)) {
C
Casey Schaufler 已提交
1659
		rc = smk_curacc(smk_of_inode(inode), MAY_READ, &ad);
C
Casey Schaufler 已提交
1660 1661
		rc = smk_bu_file(file, MAY_READ, rc);
	}
1662 1663 1664 1665 1666 1667 1668

	return rc;
}

/**
 * smack_file_lock - Smack check on file locking
 * @file: the object
1669
 * @cmd: unused
1670
 *
1671
 * Returns 0 if current has lock access, error code otherwise
1672 1673 1674
 */
static int smack_file_lock(struct file *file, unsigned int cmd)
{
E
Etienne Basset 已提交
1675
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
1676
	int rc;
C
Casey Schaufler 已提交
1677
	struct inode *inode = file_inode(file);
E
Etienne Basset 已提交
1678

1679 1680
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
	smk_ad_setfield_u_fs_path(&ad, file->f_path);
C
Casey Schaufler 已提交
1681
	rc = smk_curacc(smk_of_inode(inode), MAY_LOCK, &ad);
C
Casey Schaufler 已提交
1682 1683
	rc = smk_bu_file(file, MAY_LOCK, rc);
	return rc;
1684 1685 1686 1687 1688 1689 1690 1691
}

/**
 * smack_file_fcntl - Smack check on fcntl
 * @file: the object
 * @cmd: what action to check
 * @arg: unused
 *
1692 1693 1694 1695
 * Generally these operations are harmless.
 * File locking operations present an obvious mechanism
 * for passing information, so they require write access.
 *
1696 1697 1698 1699 1700
 * Returns 0 if current has access, error code otherwise
 */
static int smack_file_fcntl(struct file *file, unsigned int cmd,
			    unsigned long arg)
{
E
Etienne Basset 已提交
1701
	struct smk_audit_info ad;
1702
	int rc = 0;
C
Casey Schaufler 已提交
1703
	struct inode *inode = file_inode(file);
E
Etienne Basset 已提交
1704

1705 1706
	switch (cmd) {
	case F_GETLK:
1707
		break;
1708 1709
	case F_SETLK:
	case F_SETLKW:
1710 1711
		smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
		smk_ad_setfield_u_fs_path(&ad, file->f_path);
C
Casey Schaufler 已提交
1712
		rc = smk_curacc(smk_of_inode(inode), MAY_LOCK, &ad);
C
Casey Schaufler 已提交
1713
		rc = smk_bu_file(file, MAY_LOCK, rc);
1714
		break;
1715 1716
	case F_SETOWN:
	case F_SETSIG:
1717 1718
		smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
		smk_ad_setfield_u_fs_path(&ad, file->f_path);
C
Casey Schaufler 已提交
1719
		rc = smk_curacc(smk_of_inode(inode), MAY_WRITE, &ad);
C
Casey Schaufler 已提交
1720
		rc = smk_bu_file(file, MAY_WRITE, rc);
1721 1722
		break;
	default:
1723
		break;
1724 1725 1726 1727 1728
	}

	return rc;
}

1729
/**
1730
 * smack_mmap_file :
1731 1732 1733 1734 1735 1736 1737 1738
 * Check permissions for a mmap operation.  The @file may be NULL, e.g.
 * if mapping anonymous memory.
 * @file contains the file structure for file to map (may be NULL).
 * @reqprot contains the protection requested by the application.
 * @prot contains the protection that will be applied by the kernel.
 * @flags contains the operational flags.
 * Return 0 if permission is granted.
 */
1739
static int smack_mmap_file(struct file *file,
1740
			   unsigned long reqprot, unsigned long prot,
1741
			   unsigned long flags)
1742
{
1743
	struct smack_known *skp;
1744
	struct smack_known *mkp;
1745 1746
	struct smack_rule *srp;
	struct task_smack *tsp;
1747
	struct smack_known *okp;
1748
	struct inode_smack *isp;
1749
	struct superblock_smack *sbsp;
1750 1751 1752
	int may;
	int mmay;
	int tmay;
1753 1754
	int rc;

A
Al Viro 已提交
1755
	if (file == NULL)
1756 1757
		return 0;

A
Al Viro 已提交
1758
	isp = file_inode(file)->i_security;
1759 1760
	if (isp->smk_mmap == NULL)
		return 0;
1761 1762 1763 1764
	sbsp = file_inode(file)->i_sb->s_security;
	if (sbsp->smk_flags & SMK_SB_UNTRUSTED &&
	    isp->smk_mmap != sbsp->smk_root)
		return -EACCES;
1765
	mkp = isp->smk_mmap;
1766 1767

	tsp = current_security();
1768
	skp = smk_of_current();
1769 1770 1771 1772 1773 1774 1775 1776
	rc = 0;

	rcu_read_lock();
	/*
	 * For each Smack rule associated with the subject
	 * label verify that the SMACK64MMAP also has access
	 * to that rule's object label.
	 */
1777
	list_for_each_entry_rcu(srp, &skp->smk_rules, list) {
1778
		okp = srp->smk_object;
1779 1780 1781
		/*
		 * Matching labels always allows access.
		 */
1782
		if (mkp->smk_known == okp->smk_known)
1783
			continue;
1784 1785 1786 1787
		/*
		 * If there is a matching local rule take
		 * that into account as well.
		 */
1788 1789 1790
		may = smk_access_entry(srp->smk_subject->smk_known,
				       okp->smk_known,
				       &tsp->smk_rules);
1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806
		if (may == -ENOENT)
			may = srp->smk_access;
		else
			may &= srp->smk_access;
		/*
		 * If may is zero the SMACK64MMAP subject can't
		 * possibly have less access.
		 */
		if (may == 0)
			continue;

		/*
		 * Fetch the global list entry.
		 * If there isn't one a SMACK64MMAP subject
		 * can't have as much access as current.
		 */
1807 1808
		mmay = smk_access_entry(mkp->smk_known, okp->smk_known,
					&mkp->smk_rules);
1809 1810 1811 1812 1813 1814 1815 1816
		if (mmay == -ENOENT) {
			rc = -EACCES;
			break;
		}
		/*
		 * If there is a local entry it modifies the
		 * potential access, too.
		 */
1817 1818
		tmay = smk_access_entry(mkp->smk_known, okp->smk_known,
					&tsp->smk_rules);
1819 1820
		if (tmay != -ENOENT)
			mmay &= tmay;
1821

1822 1823 1824 1825 1826
		/*
		 * If there is any access available to current that is
		 * not available to a SMACK64MMAP subject
		 * deny access.
		 */
1827
		if ((may | mmay) != mmay) {
1828
			rc = -EACCES;
1829
			break;
1830
		}
1831 1832 1833 1834 1835 1836 1837
	}

	rcu_read_unlock();

	return rc;
}

1838 1839 1840 1841 1842
/**
 * smack_file_set_fowner - set the file security blob value
 * @file: object in question
 *
 */
1843
static void smack_file_set_fowner(struct file *file)
1844
{
C
Casey Schaufler 已提交
1845
	file->f_security = smk_of_current();
1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860 1861
}

/**
 * smack_file_send_sigiotask - Smack on sigio
 * @tsk: The target task
 * @fown: the object the signal come from
 * @signum: unused
 *
 * Allow a privileged task to get signals even if it shouldn't
 *
 * Returns 0 if a subject with the object's smack could
 * write to the task, an error code otherwise.
 */
static int smack_file_send_sigiotask(struct task_struct *tsk,
				     struct fown_struct *fown, int signum)
{
1862 1863
	struct smack_known *skp;
	struct smack_known *tkp = smk_of_task(tsk->cred->security);
1864 1865
	struct file *file;
	int rc;
E
Etienne Basset 已提交
1866
	struct smk_audit_info ad;
1867 1868 1869 1870 1871

	/*
	 * struct fown_struct is never outside the context of a struct file
	 */
	file = container_of(fown, struct file, f_owner);
1872

E
Etienne Basset 已提交
1873
	/* we don't log here as rc can be overriden */
1874
	skp = file->f_security;
1875 1876
	rc = smk_access(skp, tkp, MAY_DELIVER, NULL);
	rc = smk_bu_note("sigiotask", skp, tkp, MAY_DELIVER, rc);
1877
	if (rc != 0 && has_capability(tsk, CAP_MAC_OVERRIDE))
E
Etienne Basset 已提交
1878 1879 1880 1881
		rc = 0;

	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
	smk_ad_setfield_u_tsk(&ad, tsk);
1882
	smack_log(skp->smk_known, tkp->smk_known, MAY_DELIVER, rc, &ad);
1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893
	return rc;
}

/**
 * smack_file_receive - Smack file receive check
 * @file: the object
 *
 * Returns 0 if current has access, error code otherwise
 */
static int smack_file_receive(struct file *file)
{
C
Casey Schaufler 已提交
1894
	int rc;
1895
	int may = 0;
E
Etienne Basset 已提交
1896
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
1897
	struct inode *inode = file_inode(file);
C
Casey Schaufler 已提交
1898 1899 1900
	struct socket *sock;
	struct task_smack *tsp;
	struct socket_smack *ssp;
1901

1902 1903 1904
	if (unlikely(IS_PRIVATE(inode)))
		return 0;

1905
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
E
Etienne Basset 已提交
1906
	smk_ad_setfield_u_fs_path(&ad, file->f_path);
C
Casey Schaufler 已提交
1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925

	if (S_ISSOCK(inode->i_mode)) {
		sock = SOCKET_I(inode);
		ssp = sock->sk->sk_security;
		tsp = current_security();
		/*
		 * If the receiving process can't write to the
		 * passed socket or if the passed socket can't
		 * write to the receiving process don't accept
		 * the passed socket.
		 */
		rc = smk_access(tsp->smk_task, ssp->smk_out, MAY_WRITE, &ad);
		rc = smk_bu_file(file, may, rc);
		if (rc < 0)
			return rc;
		rc = smk_access(ssp->smk_in, tsp->smk_task, MAY_WRITE, &ad);
		rc = smk_bu_file(file, may, rc);
		return rc;
	}
1926 1927 1928 1929 1930 1931 1932 1933
	/*
	 * This code relies on bitmasks.
	 */
	if (file->f_mode & FMODE_READ)
		may = MAY_READ;
	if (file->f_mode & FMODE_WRITE)
		may |= MAY_WRITE;

C
Casey Schaufler 已提交
1934
	rc = smk_curacc(smk_of_inode(inode), may, &ad);
C
Casey Schaufler 已提交
1935 1936
	rc = smk_bu_file(file, may, rc);
	return rc;
1937 1938
}

1939
/**
1940
 * smack_file_open - Smack dentry open processing
1941
 * @file: the object
1942
 * @cred: task credential
1943 1944
 *
 * Set the security blob in the file structure.
1945 1946 1947
 * Allow the open only if the task has read access. There are
 * many read operations (e.g. fstat) that you can do with an
 * fd even if you have the file open write-only.
1948 1949 1950
 *
 * Returns 0
 */
1951
static int smack_file_open(struct file *file, const struct cred *cred)
1952
{
1953
	struct task_smack *tsp = cred->security;
C
Casey Schaufler 已提交
1954
	struct inode *inode = file_inode(file);
1955 1956
	struct smk_audit_info ad;
	int rc;
1957

1958 1959
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
	smk_ad_setfield_u_fs_path(&ad, file->f_path);
1960
	rc = smk_tskacc(tsp, smk_of_inode(inode), MAY_READ, &ad);
C
Casey Schaufler 已提交
1961
	rc = smk_bu_credfile(cred, file, MAY_READ, rc);
1962 1963

	return rc;
1964 1965
}

1966 1967 1968 1969
/*
 * Task hooks
 */

1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980
/**
 * smack_cred_alloc_blank - "allocate" blank task-level security credentials
 * @new: the new credentials
 * @gfp: the atomicity of any memory allocations
 *
 * Prepare a blank set of credentials for modification.  This must allocate all
 * the memory the LSM module might require such that cred_transfer() can
 * complete without error.
 */
static int smack_cred_alloc_blank(struct cred *cred, gfp_t gfp)
{
1981 1982 1983 1984
	struct task_smack *tsp;

	tsp = new_task_smack(NULL, NULL, gfp);
	if (tsp == NULL)
1985
		return -ENOMEM;
1986 1987 1988

	cred->security = tsp;

1989 1990 1991 1992
	return 0;
}


1993
/**
1994 1995
 * smack_cred_free - "free" task-level security credentials
 * @cred: the credentials in question
1996 1997
 *
 */
1998
static void smack_cred_free(struct cred *cred)
1999
{
2000 2001 2002 2003 2004 2005 2006 2007 2008
	struct task_smack *tsp = cred->security;
	struct smack_rule *rp;
	struct list_head *l;
	struct list_head *n;

	if (tsp == NULL)
		return;
	cred->security = NULL;

2009 2010
	smk_destroy_label_list(&tsp->smk_relabel);

2011 2012 2013 2014 2015 2016
	list_for_each_safe(l, n, &tsp->smk_rules) {
		rp = list_entry(l, struct smack_rule, list);
		list_del(&rp->list);
		kfree(rp);
	}
	kfree(tsp);
2017 2018
}

D
David Howells 已提交
2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029
/**
 * smack_cred_prepare - prepare new set of credentials for modification
 * @new: the new credentials
 * @old: the original credentials
 * @gfp: the atomicity of any memory allocations
 *
 * Prepare a new set of credentials for modification.
 */
static int smack_cred_prepare(struct cred *new, const struct cred *old,
			      gfp_t gfp)
{
2030 2031
	struct task_smack *old_tsp = old->security;
	struct task_smack *new_tsp;
2032
	int rc;
2033

2034
	new_tsp = new_task_smack(old_tsp->smk_task, old_tsp->smk_task, gfp);
2035 2036 2037
	if (new_tsp == NULL)
		return -ENOMEM;

2038 2039
	new->security = new_tsp;

2040 2041 2042 2043
	rc = smk_copy_rules(&new_tsp->smk_rules, &old_tsp->smk_rules, gfp);
	if (rc != 0)
		return rc;

2044 2045 2046 2047 2048
	rc = smk_copy_relabel(&new_tsp->smk_relabel, &old_tsp->smk_relabel,
				gfp);
	if (rc != 0)
		return rc;

D
David Howells 已提交
2049 2050 2051
	return 0;
}

2052 2053 2054 2055 2056 2057 2058 2059 2060
/**
 * smack_cred_transfer - Transfer the old credentials to the new credentials
 * @new: the new credentials
 * @old: the original credentials
 *
 * Fill in a set of blank credentials from another set of credentials.
 */
static void smack_cred_transfer(struct cred *new, const struct cred *old)
{
2061 2062 2063 2064 2065
	struct task_smack *old_tsp = old->security;
	struct task_smack *new_tsp = new->security;

	new_tsp->smk_task = old_tsp->smk_task;
	new_tsp->smk_forked = old_tsp->smk_task;
2066 2067 2068 2069 2070
	mutex_init(&new_tsp->smk_rules_lock);
	INIT_LIST_HEAD(&new_tsp->smk_rules);


	/* cbs copy rule list */
2071 2072
}

2073 2074
/**
 * smack_kernel_act_as - Set the subjective context in a set of credentials
2075 2076
 * @new: points to the set of credentials to be modified.
 * @secid: specifies the security ID to be set
2077 2078 2079 2080 2081
 *
 * Set the security data for a kernel service.
 */
static int smack_kernel_act_as(struct cred *new, u32 secid)
{
2082
	struct task_smack *new_tsp = new->security;
2083

2084
	new_tsp->smk_task = smack_from_secid(secid);
2085 2086 2087 2088 2089
	return 0;
}

/**
 * smack_kernel_create_files_as - Set the file creation label in a set of creds
2090 2091
 * @new: points to the set of credentials to be modified
 * @inode: points to the inode to use as a reference
2092 2093 2094 2095 2096 2097 2098 2099
 *
 * Set the file creation context in a set of credentials to the same
 * as the objective context of the specified inode
 */
static int smack_kernel_create_files_as(struct cred *new,
					struct inode *inode)
{
	struct inode_smack *isp = inode->i_security;
2100
	struct task_smack *tsp = new->security;
2101

2102
	tsp->smk_forked = isp->smk_inode;
2103
	tsp->smk_task = tsp->smk_forked;
2104 2105 2106
	return 0;
}

E
Etienne Basset 已提交
2107 2108 2109
/**
 * smk_curacc_on_task - helper to log task related access
 * @p: the task object
2110 2111
 * @access: the access requested
 * @caller: name of the calling function for audit
E
Etienne Basset 已提交
2112 2113 2114
 *
 * Return 0 if access is permitted
 */
2115 2116
static int smk_curacc_on_task(struct task_struct *p, int access,
				const char *caller)
E
Etienne Basset 已提交
2117 2118
{
	struct smk_audit_info ad;
2119
	struct smack_known *skp = smk_of_task_struct(p);
C
Casey Schaufler 已提交
2120
	int rc;
E
Etienne Basset 已提交
2121

2122
	smk_ad_init(&ad, caller, LSM_AUDIT_DATA_TASK);
E
Etienne Basset 已提交
2123
	smk_ad_setfield_u_tsk(&ad, p);
2124
	rc = smk_curacc(skp, access, &ad);
C
Casey Schaufler 已提交
2125 2126
	rc = smk_bu_task(p, access, rc);
	return rc;
E
Etienne Basset 已提交
2127 2128
}

2129 2130 2131 2132 2133 2134 2135 2136 2137
/**
 * smack_task_setpgid - Smack check on setting pgid
 * @p: the task object
 * @pgid: unused
 *
 * Return 0 if write access is permitted
 */
static int smack_task_setpgid(struct task_struct *p, pid_t pgid)
{
2138
	return smk_curacc_on_task(p, MAY_WRITE, __func__);
2139 2140 2141 2142 2143 2144 2145 2146 2147 2148
}

/**
 * smack_task_getpgid - Smack access check for getpgid
 * @p: the object task
 *
 * Returns 0 if current can read the object task, error code otherwise
 */
static int smack_task_getpgid(struct task_struct *p)
{
2149
	return smk_curacc_on_task(p, MAY_READ, __func__);
2150 2151 2152 2153 2154 2155 2156 2157 2158 2159
}

/**
 * smack_task_getsid - Smack access check for getsid
 * @p: the object task
 *
 * Returns 0 if current can read the object task, error code otherwise
 */
static int smack_task_getsid(struct task_struct *p)
{
2160
	return smk_curacc_on_task(p, MAY_READ, __func__);
2161 2162 2163 2164 2165 2166 2167 2168 2169 2170 2171
}

/**
 * smack_task_getsecid - get the secid of the task
 * @p: the object task
 * @secid: where to put the result
 *
 * Sets the secid to contain a u32 version of the smack label.
 */
static void smack_task_getsecid(struct task_struct *p, u32 *secid)
{
2172
	struct smack_known *skp = smk_of_task_struct(p);
2173 2174

	*secid = skp->smk_secid;
2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185
}

/**
 * smack_task_setnice - Smack check on setting nice
 * @p: the task object
 * @nice: unused
 *
 * Return 0 if write access is permitted
 */
static int smack_task_setnice(struct task_struct *p, int nice)
{
C
Casey Schaufler 已提交
2186
	return smk_curacc_on_task(p, MAY_WRITE, __func__);
2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197
}

/**
 * smack_task_setioprio - Smack check on setting ioprio
 * @p: the task object
 * @ioprio: unused
 *
 * Return 0 if write access is permitted
 */
static int smack_task_setioprio(struct task_struct *p, int ioprio)
{
C
Casey Schaufler 已提交
2198
	return smk_curacc_on_task(p, MAY_WRITE, __func__);
2199 2200 2201 2202 2203 2204 2205 2206 2207 2208
}

/**
 * smack_task_getioprio - Smack check on reading ioprio
 * @p: the task object
 *
 * Return 0 if read access is permitted
 */
static int smack_task_getioprio(struct task_struct *p)
{
2209
	return smk_curacc_on_task(p, MAY_READ, __func__);
2210 2211 2212 2213 2214 2215 2216 2217 2218 2219
}

/**
 * smack_task_setscheduler - Smack check on setting scheduler
 * @p: the task object
 * @policy: unused
 * @lp: unused
 *
 * Return 0 if read access is permitted
 */
2220
static int smack_task_setscheduler(struct task_struct *p)
2221
{
C
Casey Schaufler 已提交
2222
	return smk_curacc_on_task(p, MAY_WRITE, __func__);
2223 2224 2225 2226 2227 2228 2229 2230 2231 2232
}

/**
 * smack_task_getscheduler - Smack check on reading scheduler
 * @p: the task object
 *
 * Return 0 if read access is permitted
 */
static int smack_task_getscheduler(struct task_struct *p)
{
2233
	return smk_curacc_on_task(p, MAY_READ, __func__);
2234 2235 2236 2237 2238 2239 2240 2241 2242 2243
}

/**
 * smack_task_movememory - Smack check on moving memory
 * @p: the task object
 *
 * Return 0 if write access is permitted
 */
static int smack_task_movememory(struct task_struct *p)
{
2244
	return smk_curacc_on_task(p, MAY_WRITE, __func__);
2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261
}

/**
 * smack_task_kill - Smack check on signal delivery
 * @p: the task object
 * @info: unused
 * @sig: unused
 * @secid: identifies the smack to use in lieu of current's
 *
 * Return 0 if write access is permitted
 *
 * The secid behavior is an artifact of an SELinux hack
 * in the USB code. Someday it may go away.
 */
static int smack_task_kill(struct task_struct *p, struct siginfo *info,
			   int sig, u32 secid)
{
E
Etienne Basset 已提交
2262
	struct smk_audit_info ad;
2263
	struct smack_known *skp;
2264
	struct smack_known *tkp = smk_of_task_struct(p);
C
Casey Schaufler 已提交
2265
	int rc;
E
Etienne Basset 已提交
2266

2267 2268 2269
	if (!sig)
		return 0; /* null signal; existence test */

E
Etienne Basset 已提交
2270 2271
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
	smk_ad_setfield_u_tsk(&ad, p);
2272 2273 2274 2275
	/*
	 * Sending a signal requires that the sender
	 * can write the receiver.
	 */
C
Casey Schaufler 已提交
2276
	if (secid == 0) {
2277 2278
		rc = smk_curacc(tkp, MAY_DELIVER, &ad);
		rc = smk_bu_task(p, MAY_DELIVER, rc);
C
Casey Schaufler 已提交
2279 2280
		return rc;
	}
2281 2282 2283 2284 2285
	/*
	 * If the secid isn't 0 we're dealing with some USB IO
	 * specific behavior. This is not clean. For one thing
	 * we can't take privilege into account.
	 */
2286
	skp = smack_from_secid(secid);
2287 2288
	rc = smk_access(skp, tkp, MAY_DELIVER, &ad);
	rc = smk_bu_note("USB signal", skp, tkp, MAY_DELIVER, rc);
C
Casey Schaufler 已提交
2289
	return rc;
2290 2291 2292 2293 2294 2295
}

/**
 * smack_task_wait - Smack access check for waiting
 * @p: task to wait for
 *
2296
 * Returns 0
2297 2298 2299 2300
 */
static int smack_task_wait(struct task_struct *p)
{
	/*
2301 2302 2303 2304 2305 2306
	 * Allow the operation to succeed.
	 * Zombies are bad.
	 * In userless environments (e.g. phones) programs
	 * get marked with SMACK64EXEC and even if the parent
	 * and child shouldn't be talking the parent still
	 * may expect to know when the child exits.
2307
	 */
2308
	return 0;
2309 2310 2311 2312 2313
}

/**
 * smack_task_to_inode - copy task smack into the inode blob
 * @p: task to copy from
2314
 * @inode: inode to copy to
2315 2316 2317 2318 2319 2320
 *
 * Sets the smack pointer in the inode security blob
 */
static void smack_task_to_inode(struct task_struct *p, struct inode *inode)
{
	struct inode_smack *isp = inode->i_security;
2321
	struct smack_known *skp = smk_of_task_struct(p);
2322

2323
	isp->smk_inode = skp;
2324 2325 2326 2327 2328 2329 2330 2331 2332 2333
}

/*
 * Socket hooks.
 */

/**
 * smack_sk_alloc_security - Allocate a socket blob
 * @sk: the socket
 * @family: unused
2334
 * @gfp_flags: memory allocation flags
2335 2336 2337 2338 2339 2340 2341
 *
 * Assign Smack pointers to current
 *
 * Returns 0 on success, -ENOMEM is there's no memory
 */
static int smack_sk_alloc_security(struct sock *sk, int family, gfp_t gfp_flags)
{
2342
	struct smack_known *skp = smk_of_current();
2343 2344 2345 2346 2347 2348
	struct socket_smack *ssp;

	ssp = kzalloc(sizeof(struct socket_smack), gfp_flags);
	if (ssp == NULL)
		return -ENOMEM;

2349 2350 2351 2352 2353 2354 2355 2356 2357 2358
	/*
	 * Sockets created by kernel threads receive web label.
	 */
	if (unlikely(current->flags & PF_KTHREAD)) {
		ssp->smk_in = &smack_known_web;
		ssp->smk_out = &smack_known_web;
	} else {
		ssp->smk_in = skp;
		ssp->smk_out = skp;
	}
2359
	ssp->smk_packet = NULL;
2360 2361 2362 2363 2364 2365 2366 2367 2368 2369 2370 2371 2372 2373

	sk->sk_security = ssp;

	return 0;
}

/**
 * smack_sk_free_security - Free a socket blob
 * @sk: the socket
 *
 * Clears the blob pointer
 */
static void smack_sk_free_security(struct sock *sk)
{
2374 2375 2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387
#ifdef SMACK_IPV6_PORT_LABELING
	struct smk_port_label *spp;

	if (sk->sk_family == PF_INET6) {
		rcu_read_lock();
		list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) {
			if (spp->smk_sock != sk)
				continue;
			spp->smk_can_reuse = 1;
			break;
		}
		rcu_read_unlock();
	}
#endif
2388 2389 2390
	kfree(sk->sk_security);
}

2391
/**
C
Casey Schaufler 已提交
2392
* smack_ipv4host_label - check host based restrictions
2393 2394 2395 2396 2397 2398 2399 2400 2401 2402
* @sip: the object end
*
* looks for host based access restrictions
*
* This version will only be appropriate for really small sets of single label
* hosts.  The caller is responsible for ensuring that the RCU read lock is
* taken before calling this function.
*
* Returns the label of the far end or NULL if it's not special.
*/
C
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2403
static struct smack_known *smack_ipv4host_label(struct sockaddr_in *sip)
2404
{
C
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2405
	struct smk_net4addr *snp;
2406 2407 2408 2409 2410
	struct in_addr *siap = &sip->sin_addr;

	if (siap->s_addr == 0)
		return NULL;

C
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2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436 2437 2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 2467
	list_for_each_entry_rcu(snp, &smk_net4addr_list, list)
		/*
		 * we break after finding the first match because
		 * the list is sorted from longest to shortest mask
		 * so we have found the most specific match
		 */
		if (snp->smk_host.s_addr ==
		    (siap->s_addr & snp->smk_mask.s_addr))
			return snp->smk_label;

	return NULL;
}

#if IS_ENABLED(CONFIG_IPV6)
/*
 * smk_ipv6_localhost - Check for local ipv6 host address
 * @sip: the address
 *
 * Returns boolean true if this is the localhost address
 */
static bool smk_ipv6_localhost(struct sockaddr_in6 *sip)
{
	__be16 *be16p = (__be16 *)&sip->sin6_addr;
	__be32 *be32p = (__be32 *)&sip->sin6_addr;

	if (be32p[0] == 0 && be32p[1] == 0 && be32p[2] == 0 && be16p[6] == 0 &&
	    ntohs(be16p[7]) == 1)
		return true;
	return false;
}

/**
* smack_ipv6host_label - check host based restrictions
* @sip: the object end
*
* looks for host based access restrictions
*
* This version will only be appropriate for really small sets of single label
* hosts.  The caller is responsible for ensuring that the RCU read lock is
* taken before calling this function.
*
* Returns the label of the far end or NULL if it's not special.
*/
static struct smack_known *smack_ipv6host_label(struct sockaddr_in6 *sip)
{
	struct smk_net6addr *snp;
	struct in6_addr *sap = &sip->sin6_addr;
	int i;
	int found = 0;

	/*
	 * It's local. Don't look for a host label.
	 */
	if (smk_ipv6_localhost(sip))
		return NULL;

	list_for_each_entry_rcu(snp, &smk_net6addr_list, list) {
C
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2468 2469 2470 2471 2472 2473
		/*
		 * If the label is NULL the entry has
		 * been renounced. Ignore it.
		 */
		if (snp->smk_label == NULL)
			continue;
2474 2475 2476 2477 2478
		/*
		* we break after finding the first match because
		* the list is sorted from longest to shortest mask
		* so we have found the most specific match
		*/
C
Casey Schaufler 已提交
2479 2480 2481 2482 2483 2484
		for (found = 1, i = 0; i < 8; i++) {
			if ((sap->s6_addr16[i] & snp->smk_mask.s6_addr16[i]) !=
			    snp->smk_host.s6_addr16[i]) {
				found = 0;
				break;
			}
2485
		}
C
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2486 2487 2488
		if (found)
			return snp->smk_label;
	}
2489 2490 2491

	return NULL;
}
C
Casey Schaufler 已提交
2492
#endif /* CONFIG_IPV6 */
2493

2494 2495 2496
/**
 * smack_netlabel - Set the secattr on a socket
 * @sk: the socket
2497
 * @labeled: socket label scheme
2498 2499 2500 2501 2502 2503
 *
 * Convert the outbound smack value (smk_out) to a
 * secattr and attach it to the socket.
 *
 * Returns 0 on success or an error code
 */
2504
static int smack_netlabel(struct sock *sk, int labeled)
2505
{
2506
	struct smack_known *skp;
2507
	struct socket_smack *ssp = sk->sk_security;
2508
	int rc = 0;
2509

2510 2511 2512 2513 2514 2515 2516 2517 2518 2519 2520 2521 2522 2523 2524
	/*
	 * Usually the netlabel code will handle changing the
	 * packet labeling based on the label.
	 * The case of a single label host is different, because
	 * a single label host should never get a labeled packet
	 * even though the label is usually associated with a packet
	 * label.
	 */
	local_bh_disable();
	bh_lock_sock_nested(sk);

	if (ssp->smk_out == smack_net_ambient ||
	    labeled == SMACK_UNLABELED_SOCKET)
		netlbl_sock_delattr(sk);
	else {
2525
		skp = ssp->smk_out;
2526
		rc = netlbl_sock_setattr(sk, sk->sk_family, &skp->smk_netlabel);
2527 2528 2529 2530
	}

	bh_unlock_sock(sk);
	local_bh_enable();
2531

2532 2533 2534
	return rc;
}

2535 2536 2537 2538 2539 2540 2541 2542 2543 2544 2545 2546 2547
/**
 * smack_netlbel_send - Set the secattr on a socket and perform access checks
 * @sk: the socket
 * @sap: the destination address
 *
 * Set the correct secattr for the given socket based on the destination
 * address and perform any outbound access checks needed.
 *
 * Returns 0 on success or an error code.
 *
 */
static int smack_netlabel_send(struct sock *sk, struct sockaddr_in *sap)
{
2548
	struct smack_known *skp;
2549 2550
	int rc;
	int sk_lbl;
2551
	struct smack_known *hkp;
2552
	struct socket_smack *ssp = sk->sk_security;
E
Etienne Basset 已提交
2553
	struct smk_audit_info ad;
2554 2555

	rcu_read_lock();
C
Casey Schaufler 已提交
2556
	hkp = smack_ipv4host_label(sap);
2557
	if (hkp != NULL) {
E
Etienne Basset 已提交
2558
#ifdef CONFIG_AUDIT
2559 2560
		struct lsm_network_audit net;

2561 2562 2563 2564
		smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
		ad.a.u.net->family = sap->sin_family;
		ad.a.u.net->dport = sap->sin_port;
		ad.a.u.net->v4info.daddr = sap->sin_addr.s_addr;
E
Etienne Basset 已提交
2565
#endif
2566
		sk_lbl = SMACK_UNLABELED_SOCKET;
2567
		skp = ssp->smk_out;
2568 2569
		rc = smk_access(skp, hkp, MAY_WRITE, &ad);
		rc = smk_bu_note("IPv4 host check", skp, hkp, MAY_WRITE, rc);
2570 2571 2572 2573 2574 2575 2576 2577 2578 2579 2580
	} else {
		sk_lbl = SMACK_CIPSO_SOCKET;
		rc = 0;
	}
	rcu_read_unlock();
	if (rc != 0)
		return rc;

	return smack_netlabel(sk, sk_lbl);
}

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Casey Schaufler 已提交
2581 2582 2583 2584 2585 2586 2587 2588 2589 2590 2591 2592 2593 2594 2595 2596 2597 2598 2599 2600 2601 2602 2603 2604 2605 2606 2607 2608 2609 2610 2611 2612 2613 2614 2615 2616
#if IS_ENABLED(CONFIG_IPV6)
/**
 * smk_ipv6_check - check Smack access
 * @subject: subject Smack label
 * @object: object Smack label
 * @address: address
 * @act: the action being taken
 *
 * Check an IPv6 access
 */
static int smk_ipv6_check(struct smack_known *subject,
				struct smack_known *object,
				struct sockaddr_in6 *address, int act)
{
#ifdef CONFIG_AUDIT
	struct lsm_network_audit net;
#endif
	struct smk_audit_info ad;
	int rc;

#ifdef CONFIG_AUDIT
	smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
	ad.a.u.net->family = PF_INET6;
	ad.a.u.net->dport = ntohs(address->sin6_port);
	if (act == SMK_RECEIVING)
		ad.a.u.net->v6info.saddr = address->sin6_addr;
	else
		ad.a.u.net->v6info.daddr = address->sin6_addr;
#endif
	rc = smk_access(subject, object, MAY_WRITE, &ad);
	rc = smk_bu_note("IPv6 check", subject, object, MAY_WRITE, rc);
	return rc;
}
#endif /* CONFIG_IPV6 */

#ifdef SMACK_IPV6_PORT_LABELING
2617 2618 2619 2620 2621 2622 2623 2624 2625 2626 2627 2628 2629 2630 2631 2632 2633 2634 2635 2636 2637
/**
 * smk_ipv6_port_label - Smack port access table management
 * @sock: socket
 * @address: address
 *
 * Create or update the port list entry
 */
static void smk_ipv6_port_label(struct socket *sock, struct sockaddr *address)
{
	struct sock *sk = sock->sk;
	struct sockaddr_in6 *addr6;
	struct socket_smack *ssp = sock->sk->sk_security;
	struct smk_port_label *spp;
	unsigned short port = 0;

	if (address == NULL) {
		/*
		 * This operation is changing the Smack information
		 * on the bound socket. Take the changes to the port
		 * as well.
		 */
2638 2639
		rcu_read_lock();
		list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) {
2640 2641 2642 2643
			if (sk != spp->smk_sock)
				continue;
			spp->smk_in = ssp->smk_in;
			spp->smk_out = ssp->smk_out;
2644
			rcu_read_unlock();
2645 2646 2647 2648 2649 2650
			return;
		}
		/*
		 * A NULL address is only used for updating existing
		 * bound entries. If there isn't one, it's OK.
		 */
2651
		rcu_read_unlock();
2652 2653 2654 2655 2656 2657 2658 2659 2660 2661 2662 2663 2664 2665 2666
		return;
	}

	addr6 = (struct sockaddr_in6 *)address;
	port = ntohs(addr6->sin6_port);
	/*
	 * This is a special case that is safely ignored.
	 */
	if (port == 0)
		return;

	/*
	 * Look for an existing port list entry.
	 * This is an indication that a port is getting reused.
	 */
2667 2668
	rcu_read_lock();
	list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) {
2669
		if (spp->smk_port != port || spp->smk_sock_type != sock->type)
2670
			continue;
2671 2672 2673 2674
		if (spp->smk_can_reuse != 1) {
			rcu_read_unlock();
			return;
		}
2675 2676 2677 2678
		spp->smk_port = port;
		spp->smk_sock = sk;
		spp->smk_in = ssp->smk_in;
		spp->smk_out = ssp->smk_out;
2679
		spp->smk_can_reuse = 0;
2680
		rcu_read_unlock();
2681 2682
		return;
	}
2683
	rcu_read_unlock();
2684 2685 2686 2687 2688 2689 2690 2691 2692 2693 2694
	/*
	 * A new port entry is required.
	 */
	spp = kzalloc(sizeof(*spp), GFP_KERNEL);
	if (spp == NULL)
		return;

	spp->smk_port = port;
	spp->smk_sock = sk;
	spp->smk_in = ssp->smk_in;
	spp->smk_out = ssp->smk_out;
2695
	spp->smk_sock_type = sock->type;
2696
	spp->smk_can_reuse = 0;
2697

2698 2699 2700
	mutex_lock(&smack_ipv6_lock);
	list_add_rcu(&spp->list, &smk_ipv6_port_list);
	mutex_unlock(&smack_ipv6_lock);
2701 2702 2703 2704 2705 2706 2707 2708 2709 2710
	return;
}

/**
 * smk_ipv6_port_check - check Smack port access
 * @sock: socket
 * @address: address
 *
 * Create or update the port list entry
 */
2711
static int smk_ipv6_port_check(struct sock *sk, struct sockaddr_in6 *address,
2712 2713 2714 2715
				int act)
{
	struct smk_port_label *spp;
	struct socket_smack *ssp = sk->sk_security;
C
Casey Schaufler 已提交
2716 2717
	struct smack_known *skp = NULL;
	unsigned short port;
2718
	struct smack_known *object;
2719 2720

	if (act == SMK_RECEIVING) {
C
Casey Schaufler 已提交
2721
		skp = smack_ipv6host_label(address);
2722
		object = ssp->smk_in;
2723
	} else {
2724
		skp = ssp->smk_out;
C
Casey Schaufler 已提交
2725
		object = smack_ipv6host_label(address);
2726 2727 2728
	}

	/*
C
Casey Schaufler 已提交
2729
	 * The other end is a single label host.
2730
	 */
C
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2731 2732 2733 2734 2735 2736
	if (skp != NULL && object != NULL)
		return smk_ipv6_check(skp, object, address, act);
	if (skp == NULL)
		skp = smack_net_ambient;
	if (object == NULL)
		object = smack_net_ambient;
2737 2738 2739 2740

	/*
	 * It's remote, so port lookup does no good.
	 */
C
Casey Schaufler 已提交
2741 2742
	if (!smk_ipv6_localhost(address))
		return smk_ipv6_check(skp, object, address, act);
2743 2744 2745 2746

	/*
	 * It's local so the send check has to have passed.
	 */
C
Casey Schaufler 已提交
2747 2748
	if (act == SMK_RECEIVING)
		return 0;
2749

C
Casey Schaufler 已提交
2750
	port = ntohs(address->sin6_port);
2751 2752
	rcu_read_lock();
	list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) {
2753
		if (spp->smk_port != port || spp->smk_sock_type != sk->sk_type)
2754
			continue;
2755
		object = spp->smk_in;
2756
		if (act == SMK_CONNECTING)
2757
			ssp->smk_packet = spp->smk_out;
2758 2759
		break;
	}
2760
	rcu_read_unlock();
2761

C
Casey Schaufler 已提交
2762
	return smk_ipv6_check(skp, object, address, act);
2763
}
C
Casey Schaufler 已提交
2764
#endif /* SMACK_IPV6_PORT_LABELING */
2765

2766 2767 2768 2769 2770 2771 2772 2773 2774 2775 2776 2777 2778 2779 2780
/**
 * smack_inode_setsecurity - set smack xattrs
 * @inode: the object
 * @name: attribute name
 * @value: attribute value
 * @size: size of the attribute
 * @flags: unused
 *
 * Sets the named attribute in the appropriate blob
 *
 * Returns 0 on success, or an error code
 */
static int smack_inode_setsecurity(struct inode *inode, const char *name,
				   const void *value, size_t size, int flags)
{
2781
	struct smack_known *skp;
2782 2783 2784
	struct inode_smack *nsp = inode->i_security;
	struct socket_smack *ssp;
	struct socket *sock;
2785
	int rc = 0;
2786

2787
	if (value == NULL || size > SMK_LONGLABEL || size == 0)
P
Pankaj Kumar 已提交
2788
		return -EINVAL;
2789

2790
	skp = smk_import_entry(value, size);
2791 2792
	if (IS_ERR(skp))
		return PTR_ERR(skp);
2793 2794

	if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
2795
		nsp->smk_inode = skp;
2796
		nsp->smk_flags |= SMK_INODE_INSTANT;
2797 2798 2799 2800 2801 2802 2803 2804 2805
		return 0;
	}
	/*
	 * The rest of the Smack xattrs are only on sockets.
	 */
	if (inode->i_sb->s_magic != SOCKFS_MAGIC)
		return -EOPNOTSUPP;

	sock = SOCKET_I(inode);
2806
	if (sock == NULL || sock->sk == NULL)
2807 2808 2809 2810 2811
		return -EOPNOTSUPP;

	ssp = sock->sk->sk_security;

	if (strcmp(name, XATTR_SMACK_IPIN) == 0)
2812
		ssp->smk_in = skp;
2813
	else if (strcmp(name, XATTR_SMACK_IPOUT) == 0) {
2814
		ssp->smk_out = skp;
2815
		if (sock->sk->sk_family == PF_INET) {
C
Casey Schaufler 已提交
2816 2817 2818 2819 2820 2821
			rc = smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET);
			if (rc != 0)
				printk(KERN_WARNING
					"Smack: \"%s\" netlbl error %d.\n",
					__func__, -rc);
		}
2822 2823 2824
	} else
		return -EOPNOTSUPP;

C
Casey Schaufler 已提交
2825
#ifdef SMACK_IPV6_PORT_LABELING
2826 2827
	if (sock->sk->sk_family == PF_INET6)
		smk_ipv6_port_label(sock, NULL);
C
Casey Schaufler 已提交
2828
#endif
2829

2830 2831 2832 2833 2834 2835 2836 2837 2838 2839 2840 2841 2842 2843 2844 2845 2846 2847
	return 0;
}

/**
 * smack_socket_post_create - finish socket setup
 * @sock: the socket
 * @family: protocol family
 * @type: unused
 * @protocol: unused
 * @kern: unused
 *
 * Sets the netlabel information on the socket
 *
 * Returns 0 on success, and error code otherwise
 */
static int smack_socket_post_create(struct socket *sock, int family,
				    int type, int protocol, int kern)
{
2848 2849 2850 2851 2852 2853 2854 2855 2856 2857 2858 2859 2860 2861 2862
	struct socket_smack *ssp;

	if (sock->sk == NULL)
		return 0;

	/*
	 * Sockets created by kernel threads receive web label.
	 */
	if (unlikely(current->flags & PF_KTHREAD)) {
		ssp = sock->sk->sk_security;
		ssp->smk_in = &smack_known_web;
		ssp->smk_out = &smack_known_web;
	}

	if (family != PF_INET)
2863 2864 2865 2866
		return 0;
	/*
	 * Set the outbound netlbl.
	 */
2867 2868 2869
	return smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET);
}

C
Casey Schaufler 已提交
2870
#ifdef SMACK_IPV6_PORT_LABELING
2871 2872 2873 2874 2875 2876 2877 2878 2879 2880 2881 2882 2883 2884 2885 2886 2887
/**
 * smack_socket_bind - record port binding information.
 * @sock: the socket
 * @address: the port address
 * @addrlen: size of the address
 *
 * Records the label bound to a port.
 *
 * Returns 0
 */
static int smack_socket_bind(struct socket *sock, struct sockaddr *address,
				int addrlen)
{
	if (sock->sk != NULL && sock->sk->sk_family == PF_INET6)
		smk_ipv6_port_label(sock, address);
	return 0;
}
C
Casey Schaufler 已提交
2888
#endif /* SMACK_IPV6_PORT_LABELING */
2889

2890 2891 2892 2893 2894 2895 2896 2897 2898 2899 2900 2901 2902
/**
 * smack_socket_connect - connect access check
 * @sock: the socket
 * @sap: the other end
 * @addrlen: size of sap
 *
 * Verifies that a connection may be possible
 *
 * Returns 0 on success, and error code otherwise
 */
static int smack_socket_connect(struct socket *sock, struct sockaddr *sap,
				int addrlen)
{
2903
	int rc = 0;
C
Casey Schaufler 已提交
2904 2905 2906 2907 2908 2909 2910
#if IS_ENABLED(CONFIG_IPV6)
	struct sockaddr_in6 *sip = (struct sockaddr_in6 *)sap;
#endif
#ifdef SMACK_IPV6_SECMARK_LABELING
	struct smack_known *rsp;
	struct socket_smack *ssp = sock->sk->sk_security;
#endif
2911 2912

	if (sock->sk == NULL)
2913 2914
		return 0;

2915 2916 2917 2918 2919 2920 2921 2922 2923
	switch (sock->sk->sk_family) {
	case PF_INET:
		if (addrlen < sizeof(struct sockaddr_in))
			return -EINVAL;
		rc = smack_netlabel_send(sock->sk, (struct sockaddr_in *)sap);
		break;
	case PF_INET6:
		if (addrlen < sizeof(struct sockaddr_in6))
			return -EINVAL;
C
Casey Schaufler 已提交
2924 2925 2926 2927
#ifdef SMACK_IPV6_SECMARK_LABELING
		rsp = smack_ipv6host_label(sip);
		if (rsp != NULL)
			rc = smk_ipv6_check(ssp->smk_out, rsp, sip,
2928
						SMK_CONNECTING);
C
Casey Schaufler 已提交
2929 2930 2931 2932
#endif
#ifdef SMACK_IPV6_PORT_LABELING
		rc = smk_ipv6_port_check(sock->sk, sip, SMK_CONNECTING);
#endif
2933 2934 2935
		break;
	}
	return rc;
2936 2937 2938 2939 2940 2941 2942 2943 2944 2945 2946 2947 2948 2949 2950 2951 2952 2953 2954 2955 2956 2957 2958 2959 2960 2961 2962 2963 2964 2965
}

/**
 * smack_flags_to_may - convert S_ to MAY_ values
 * @flags: the S_ value
 *
 * Returns the equivalent MAY_ value
 */
static int smack_flags_to_may(int flags)
{
	int may = 0;

	if (flags & S_IRUGO)
		may |= MAY_READ;
	if (flags & S_IWUGO)
		may |= MAY_WRITE;
	if (flags & S_IXUGO)
		may |= MAY_EXEC;

	return may;
}

/**
 * smack_msg_msg_alloc_security - Set the security blob for msg_msg
 * @msg: the object
 *
 * Returns 0
 */
static int smack_msg_msg_alloc_security(struct msg_msg *msg)
{
2966 2967
	struct smack_known *skp = smk_of_current();

2968
	msg->security = skp;
2969 2970 2971 2972 2973 2974 2975 2976 2977 2978 2979 2980 2981 2982 2983 2984 2985 2986 2987 2988
	return 0;
}

/**
 * smack_msg_msg_free_security - Clear the security blob for msg_msg
 * @msg: the object
 *
 * Clears the blob pointer
 */
static void smack_msg_msg_free_security(struct msg_msg *msg)
{
	msg->security = NULL;
}

/**
 * smack_of_shm - the smack pointer for the shm
 * @shp: the object
 *
 * Returns a pointer to the smack value
 */
2989
static struct smack_known *smack_of_shm(struct shmid_kernel *shp)
2990
{
2991
	return (struct smack_known *)shp->shm_perm.security;
2992 2993 2994 2995 2996 2997 2998 2999 3000 3001 3002
}

/**
 * smack_shm_alloc_security - Set the security blob for shm
 * @shp: the object
 *
 * Returns 0
 */
static int smack_shm_alloc_security(struct shmid_kernel *shp)
{
	struct kern_ipc_perm *isp = &shp->shm_perm;
3003
	struct smack_known *skp = smk_of_current();
3004

3005
	isp->security = skp;
3006 3007 3008 3009 3010 3011 3012 3013 3014 3015 3016 3017 3018 3019 3020 3021
	return 0;
}

/**
 * smack_shm_free_security - Clear the security blob for shm
 * @shp: the object
 *
 * Clears the blob pointer
 */
static void smack_shm_free_security(struct shmid_kernel *shp)
{
	struct kern_ipc_perm *isp = &shp->shm_perm;

	isp->security = NULL;
}

E
Etienne Basset 已提交
3022 3023 3024 3025 3026 3027 3028 3029 3030
/**
 * smk_curacc_shm : check if current has access on shm
 * @shp : the object
 * @access : access requested
 *
 * Returns 0 if current has the requested access, error code otherwise
 */
static int smk_curacc_shm(struct shmid_kernel *shp, int access)
{
3031
	struct smack_known *ssp = smack_of_shm(shp);
E
Etienne Basset 已提交
3032
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
3033
	int rc;
E
Etienne Basset 已提交
3034 3035 3036 3037 3038

#ifdef CONFIG_AUDIT
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
	ad.a.u.ipc_id = shp->shm_perm.id;
#endif
C
Casey Schaufler 已提交
3039 3040 3041
	rc = smk_curacc(ssp, access, &ad);
	rc = smk_bu_current("shm", ssp, access, rc);
	return rc;
E
Etienne Basset 已提交
3042 3043
}

3044 3045 3046 3047 3048 3049 3050 3051 3052 3053 3054 3055
/**
 * smack_shm_associate - Smack access check for shm
 * @shp: the object
 * @shmflg: access requested
 *
 * Returns 0 if current has the requested access, error code otherwise
 */
static int smack_shm_associate(struct shmid_kernel *shp, int shmflg)
{
	int may;

	may = smack_flags_to_may(shmflg);
E
Etienne Basset 已提交
3056
	return smk_curacc_shm(shp, may);
3057 3058 3059 3060 3061 3062 3063 3064 3065 3066 3067 3068 3069 3070 3071 3072 3073 3074 3075 3076 3077 3078 3079 3080 3081 3082 3083 3084 3085 3086 3087 3088 3089
}

/**
 * smack_shm_shmctl - Smack access check for shm
 * @shp: the object
 * @cmd: what it wants to do
 *
 * Returns 0 if current has the requested access, error code otherwise
 */
static int smack_shm_shmctl(struct shmid_kernel *shp, int cmd)
{
	int may;

	switch (cmd) {
	case IPC_STAT:
	case SHM_STAT:
		may = MAY_READ;
		break;
	case IPC_SET:
	case SHM_LOCK:
	case SHM_UNLOCK:
	case IPC_RMID:
		may = MAY_READWRITE;
		break;
	case IPC_INFO:
	case SHM_INFO:
		/*
		 * System level information.
		 */
		return 0;
	default:
		return -EINVAL;
	}
E
Etienne Basset 已提交
3090
	return smk_curacc_shm(shp, may);
3091 3092 3093 3094 3095 3096 3097 3098 3099 3100 3101 3102 3103 3104 3105 3106
}

/**
 * smack_shm_shmat - Smack access for shmat
 * @shp: the object
 * @shmaddr: unused
 * @shmflg: access requested
 *
 * Returns 0 if current has the requested access, error code otherwise
 */
static int smack_shm_shmat(struct shmid_kernel *shp, char __user *shmaddr,
			   int shmflg)
{
	int may;

	may = smack_flags_to_may(shmflg);
E
Etienne Basset 已提交
3107
	return smk_curacc_shm(shp, may);
3108 3109 3110 3111 3112 3113 3114 3115
}

/**
 * smack_of_sem - the smack pointer for the sem
 * @sma: the object
 *
 * Returns a pointer to the smack value
 */
3116
static struct smack_known *smack_of_sem(struct sem_array *sma)
3117
{
3118
	return (struct smack_known *)sma->sem_perm.security;
3119 3120 3121 3122 3123 3124 3125 3126 3127 3128 3129
}

/**
 * smack_sem_alloc_security - Set the security blob for sem
 * @sma: the object
 *
 * Returns 0
 */
static int smack_sem_alloc_security(struct sem_array *sma)
{
	struct kern_ipc_perm *isp = &sma->sem_perm;
3130
	struct smack_known *skp = smk_of_current();
3131

3132
	isp->security = skp;
3133 3134 3135 3136 3137 3138 3139 3140 3141 3142 3143 3144 3145 3146 3147 3148
	return 0;
}

/**
 * smack_sem_free_security - Clear the security blob for sem
 * @sma: the object
 *
 * Clears the blob pointer
 */
static void smack_sem_free_security(struct sem_array *sma)
{
	struct kern_ipc_perm *isp = &sma->sem_perm;

	isp->security = NULL;
}

E
Etienne Basset 已提交
3149 3150 3151 3152 3153 3154 3155 3156 3157
/**
 * smk_curacc_sem : check if current has access on sem
 * @sma : the object
 * @access : access requested
 *
 * Returns 0 if current has the requested access, error code otherwise
 */
static int smk_curacc_sem(struct sem_array *sma, int access)
{
3158
	struct smack_known *ssp = smack_of_sem(sma);
E
Etienne Basset 已提交
3159
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
3160
	int rc;
E
Etienne Basset 已提交
3161 3162 3163 3164 3165

#ifdef CONFIG_AUDIT
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
	ad.a.u.ipc_id = sma->sem_perm.id;
#endif
C
Casey Schaufler 已提交
3166 3167 3168
	rc = smk_curacc(ssp, access, &ad);
	rc = smk_bu_current("sem", ssp, access, rc);
	return rc;
E
Etienne Basset 已提交
3169 3170
}

3171 3172 3173 3174 3175 3176 3177 3178 3179 3180 3181 3182
/**
 * smack_sem_associate - Smack access check for sem
 * @sma: the object
 * @semflg: access requested
 *
 * Returns 0 if current has the requested access, error code otherwise
 */
static int smack_sem_associate(struct sem_array *sma, int semflg)
{
	int may;

	may = smack_flags_to_may(semflg);
E
Etienne Basset 已提交
3183
	return smk_curacc_sem(sma, may);
3184 3185 3186 3187 3188 3189 3190 3191 3192 3193 3194 3195 3196 3197 3198 3199 3200 3201 3202 3203 3204 3205 3206 3207 3208 3209 3210 3211 3212 3213 3214 3215 3216 3217 3218 3219 3220 3221 3222
}

/**
 * smack_sem_shmctl - Smack access check for sem
 * @sma: the object
 * @cmd: what it wants to do
 *
 * Returns 0 if current has the requested access, error code otherwise
 */
static int smack_sem_semctl(struct sem_array *sma, int cmd)
{
	int may;

	switch (cmd) {
	case GETPID:
	case GETNCNT:
	case GETZCNT:
	case GETVAL:
	case GETALL:
	case IPC_STAT:
	case SEM_STAT:
		may = MAY_READ;
		break;
	case SETVAL:
	case SETALL:
	case IPC_RMID:
	case IPC_SET:
		may = MAY_READWRITE;
		break;
	case IPC_INFO:
	case SEM_INFO:
		/*
		 * System level information
		 */
		return 0;
	default:
		return -EINVAL;
	}

E
Etienne Basset 已提交
3223
	return smk_curacc_sem(sma, may);
3224 3225 3226 3227 3228 3229 3230 3231 3232 3233 3234 3235 3236 3237 3238 3239
}

/**
 * smack_sem_semop - Smack checks of semaphore operations
 * @sma: the object
 * @sops: unused
 * @nsops: unused
 * @alter: unused
 *
 * Treated as read and write in all cases.
 *
 * Returns 0 if access is allowed, error code otherwise
 */
static int smack_sem_semop(struct sem_array *sma, struct sembuf *sops,
			   unsigned nsops, int alter)
{
E
Etienne Basset 已提交
3240
	return smk_curacc_sem(sma, MAY_READWRITE);
3241 3242 3243 3244 3245 3246 3247 3248 3249 3250 3251
}

/**
 * smack_msg_alloc_security - Set the security blob for msg
 * @msq: the object
 *
 * Returns 0
 */
static int smack_msg_queue_alloc_security(struct msg_queue *msq)
{
	struct kern_ipc_perm *kisp = &msq->q_perm;
3252
	struct smack_known *skp = smk_of_current();
3253

3254
	kisp->security = skp;
3255 3256 3257 3258 3259 3260 3261 3262 3263 3264 3265 3266 3267 3268 3269 3270 3271 3272 3273 3274
	return 0;
}

/**
 * smack_msg_free_security - Clear the security blob for msg
 * @msq: the object
 *
 * Clears the blob pointer
 */
static void smack_msg_queue_free_security(struct msg_queue *msq)
{
	struct kern_ipc_perm *kisp = &msq->q_perm;

	kisp->security = NULL;
}

/**
 * smack_of_msq - the smack pointer for the msq
 * @msq: the object
 *
3275
 * Returns a pointer to the smack label entry
3276
 */
3277
static struct smack_known *smack_of_msq(struct msg_queue *msq)
3278
{
3279
	return (struct smack_known *)msq->q_perm.security;
3280 3281
}

E
Etienne Basset 已提交
3282 3283 3284 3285 3286 3287 3288 3289 3290
/**
 * smk_curacc_msq : helper to check if current has access on msq
 * @msq : the msq
 * @access : access requested
 *
 * return 0 if current has access, error otherwise
 */
static int smk_curacc_msq(struct msg_queue *msq, int access)
{
3291
	struct smack_known *msp = smack_of_msq(msq);
E
Etienne Basset 已提交
3292
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
3293
	int rc;
E
Etienne Basset 已提交
3294 3295 3296 3297 3298

#ifdef CONFIG_AUDIT
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
	ad.a.u.ipc_id = msq->q_perm.id;
#endif
C
Casey Schaufler 已提交
3299 3300 3301
	rc = smk_curacc(msp, access, &ad);
	rc = smk_bu_current("msq", msp, access, rc);
	return rc;
E
Etienne Basset 已提交
3302 3303
}

3304 3305 3306 3307 3308 3309 3310 3311 3312 3313 3314 3315
/**
 * smack_msg_queue_associate - Smack access check for msg_queue
 * @msq: the object
 * @msqflg: access requested
 *
 * Returns 0 if current has the requested access, error code otherwise
 */
static int smack_msg_queue_associate(struct msg_queue *msq, int msqflg)
{
	int may;

	may = smack_flags_to_may(msqflg);
E
Etienne Basset 已提交
3316
	return smk_curacc_msq(msq, may);
3317 3318 3319 3320 3321 3322 3323 3324 3325 3326 3327 3328 3329 3330 3331 3332 3333 3334 3335 3336 3337 3338 3339 3340 3341 3342 3343 3344 3345 3346 3347 3348
}

/**
 * smack_msg_queue_msgctl - Smack access check for msg_queue
 * @msq: the object
 * @cmd: what it wants to do
 *
 * Returns 0 if current has the requested access, error code otherwise
 */
static int smack_msg_queue_msgctl(struct msg_queue *msq, int cmd)
{
	int may;

	switch (cmd) {
	case IPC_STAT:
	case MSG_STAT:
		may = MAY_READ;
		break;
	case IPC_SET:
	case IPC_RMID:
		may = MAY_READWRITE;
		break;
	case IPC_INFO:
	case MSG_INFO:
		/*
		 * System level information
		 */
		return 0;
	default:
		return -EINVAL;
	}

E
Etienne Basset 已提交
3349
	return smk_curacc_msq(msq, may);
3350 3351 3352 3353 3354 3355 3356 3357 3358 3359 3360 3361 3362
}

/**
 * smack_msg_queue_msgsnd - Smack access check for msg_queue
 * @msq: the object
 * @msg: unused
 * @msqflg: access requested
 *
 * Returns 0 if current has the requested access, error code otherwise
 */
static int smack_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg,
				  int msqflg)
{
E
Etienne Basset 已提交
3363
	int may;
3364

E
Etienne Basset 已提交
3365 3366
	may = smack_flags_to_may(msqflg);
	return smk_curacc_msq(msq, may);
3367 3368 3369 3370 3371 3372 3373 3374 3375 3376 3377 3378 3379 3380 3381
}

/**
 * smack_msg_queue_msgsnd - Smack access check for msg_queue
 * @msq: the object
 * @msg: unused
 * @target: unused
 * @type: unused
 * @mode: unused
 *
 * Returns 0 if current has read and write access, error code otherwise
 */
static int smack_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
			struct task_struct *target, long type, int mode)
{
E
Etienne Basset 已提交
3382
	return smk_curacc_msq(msq, MAY_READWRITE);
3383 3384 3385 3386 3387 3388 3389 3390 3391 3392 3393
}

/**
 * smack_ipc_permission - Smack access for ipc_permission()
 * @ipp: the object permissions
 * @flag: access requested
 *
 * Returns 0 if current has read and write access, error code otherwise
 */
static int smack_ipc_permission(struct kern_ipc_perm *ipp, short flag)
{
3394
	struct smack_known *iskp = ipp->security;
E
Etienne Basset 已提交
3395 3396
	int may = smack_flags_to_may(flag);
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
3397
	int rc;
3398

E
Etienne Basset 已提交
3399 3400 3401 3402
#ifdef CONFIG_AUDIT
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
	ad.a.u.ipc_id = ipp->id;
#endif
3403 3404
	rc = smk_curacc(iskp, may, &ad);
	rc = smk_bu_current("svipc", iskp, may, rc);
C
Casey Schaufler 已提交
3405
	return rc;
3406 3407
}

3408 3409
/**
 * smack_ipc_getsecid - Extract smack security id
3410
 * @ipp: the object permissions
3411 3412 3413 3414
 * @secid: where result will be saved
 */
static void smack_ipc_getsecid(struct kern_ipc_perm *ipp, u32 *secid)
{
3415
	struct smack_known *iskp = ipp->security;
3416

3417
	*secid = iskp->smk_secid;
3418 3419
}

3420 3421
/**
 * smack_d_instantiate - Make sure the blob is correct on an inode
3422
 * @opt_dentry: dentry where inode will be attached
3423 3424 3425 3426 3427 3428 3429 3430 3431
 * @inode: the object
 *
 * Set the inode's security blob if it hasn't been done already.
 */
static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode)
{
	struct super_block *sbp;
	struct superblock_smack *sbsp;
	struct inode_smack *isp;
3432 3433
	struct smack_known *skp;
	struct smack_known *ckp = smk_of_current();
3434
	struct smack_known *final;
3435 3436
	char trattr[TRANS_TRUE_SIZE];
	int transflag = 0;
C
Casey Schaufler 已提交
3437
	int rc;
3438 3439 3440 3441 3442 3443 3444 3445 3446 3447 3448 3449 3450 3451 3452 3453 3454 3455 3456 3457 3458 3459 3460
	struct dentry *dp;

	if (inode == NULL)
		return;

	isp = inode->i_security;

	mutex_lock(&isp->smk_lock);
	/*
	 * If the inode is already instantiated
	 * take the quick way out
	 */
	if (isp->smk_flags & SMK_INODE_INSTANT)
		goto unlockandout;

	sbp = inode->i_sb;
	sbsp = sbp->s_security;
	/*
	 * We're going to use the superblock default label
	 * if there's no label on the file.
	 */
	final = sbsp->smk_default;

C
Casey Schaufler 已提交
3461 3462 3463 3464 3465 3466 3467
	/*
	 * If this is the root inode the superblock
	 * may be in the process of initialization.
	 * If that is the case use the root value out
	 * of the superblock.
	 */
	if (opt_dentry->d_parent == opt_dentry) {
3468 3469
		switch (sbp->s_magic) {
		case CGROUP_SUPER_MAGIC:
3470 3471 3472 3473 3474
			/*
			 * The cgroup filesystem is never mounted,
			 * so there's no opportunity to set the mount
			 * options.
			 */
3475 3476
			sbsp->smk_root = &smack_known_star;
			sbsp->smk_default = &smack_known_star;
3477 3478 3479 3480 3481 3482 3483 3484 3485
			isp->smk_inode = sbsp->smk_root;
			break;
		case TMPFS_MAGIC:
			/*
			 * What about shmem/tmpfs anonymous files with dentry
			 * obtained from d_alloc_pseudo()?
			 */
			isp->smk_inode = smk_of_current();
			break;
3486 3487 3488
		case PIPEFS_MAGIC:
			isp->smk_inode = smk_of_current();
			break;
3489 3490 3491 3492 3493 3494 3495
		case SOCKFS_MAGIC:
			/*
			 * Socket access is controlled by the socket
			 * structures associated with the task involved.
			 */
			isp->smk_inode = &smack_known_star;
			break;
3496 3497 3498
		default:
			isp->smk_inode = sbsp->smk_root;
			break;
3499
		}
C
Casey Schaufler 已提交
3500 3501 3502 3503
		isp->smk_flags |= SMK_INODE_INSTANT;
		goto unlockandout;
	}

3504 3505 3506 3507 3508 3509 3510 3511
	/*
	 * This is pretty hackish.
	 * Casey says that we shouldn't have to do
	 * file system specific code, but it does help
	 * with keeping it simple.
	 */
	switch (sbp->s_magic) {
	case SMACK_MAGIC:
3512
	case CGROUP_SUPER_MAGIC:
3513
		/*
L
Lucas De Marchi 已提交
3514
		 * Casey says that it's a little embarrassing
3515 3516
		 * that the smack file system doesn't do
		 * extended attributes.
3517 3518
		 *
		 * Cgroupfs is special
3519
		 */
3520
		final = &smack_known_star;
3521 3522 3523 3524 3525 3526 3527
		break;
	case DEVPTS_SUPER_MAGIC:
		/*
		 * devpts seems content with the label of the task.
		 * Programs that change smack have to treat the
		 * pty with respect.
		 */
3528
		final = ckp;
3529 3530 3531 3532 3533 3534 3535 3536 3537 3538 3539 3540 3541
		break;
	case PROC_SUPER_MAGIC:
		/*
		 * Casey says procfs appears not to care.
		 * The superblock default suffices.
		 */
		break;
	case TMPFS_MAGIC:
		/*
		 * Device labels should come from the filesystem,
		 * but watch out, because they're volitile,
		 * getting recreated on every reboot.
		 */
3542
		final = &smack_known_star;
3543 3544 3545 3546 3547 3548 3549 3550 3551 3552 3553 3554
		/*
		 * No break.
		 *
		 * If a smack value has been set we want to use it,
		 * but since tmpfs isn't giving us the opportunity
		 * to set mount options simulate setting the
		 * superblock default.
		 */
	default:
		/*
		 * This isn't an understood special case.
		 * Get the value from the xattr.
C
Casey Schaufler 已提交
3555 3556 3557 3558 3559 3560
		 */

		/*
		 * UNIX domain sockets use lower level socket data.
		 */
		if (S_ISSOCK(inode->i_mode)) {
3561
			final = &smack_known_star;
C
Casey Schaufler 已提交
3562 3563 3564
			break;
		}
		/*
3565 3566 3567 3568 3569
		 * No xattr support means, alas, no SMACK label.
		 * Use the aforeapplied default.
		 * It would be curious if the label of the task
		 * does not match that assigned.
		 */
3570 3571
		if (!(inode->i_opflags & IOP_XATTR))
		        break;
3572 3573 3574
		/*
		 * Get the dentry for xattr.
		 */
3575
		dp = dget(opt_dentry);
3576
		skp = smk_fetch(XATTR_NAME_SMACK, inode, dp);
3577
		if (!IS_ERR_OR_NULL(skp))
3578
			final = skp;
C
Casey Schaufler 已提交
3579 3580 3581 3582 3583 3584 3585 3586 3587 3588 3589 3590 3591 3592 3593 3594

		/*
		 * Transmuting directory
		 */
		if (S_ISDIR(inode->i_mode)) {
			/*
			 * If this is a new directory and the label was
			 * transmuted when the inode was initialized
			 * set the transmute attribute on the directory
			 * and mark the inode.
			 *
			 * If there is a transmute attribute on the
			 * directory mark the inode.
			 */
			if (isp->smk_flags & SMK_INODE_CHANGED) {
				isp->smk_flags &= ~SMK_INODE_CHANGED;
3595
				rc = __vfs_setxattr(dp, inode,
3596
					XATTR_NAME_SMACKTRANSMUTE,
C
Casey Schaufler 已提交
3597 3598 3599
					TRANS_TRUE, TRANS_TRUE_SIZE,
					0);
			} else {
3600
				rc = __vfs_getxattr(dp, inode,
C
Casey Schaufler 已提交
3601 3602 3603 3604 3605
					XATTR_NAME_SMACKTRANSMUTE, trattr,
					TRANS_TRUE_SIZE);
				if (rc >= 0 && strncmp(trattr, TRANS_TRUE,
						       TRANS_TRUE_SIZE) != 0)
					rc = -EINVAL;
3606
			}
C
Casey Schaufler 已提交
3607 3608
			if (rc >= 0)
				transflag = SMK_INODE_TRANSMUTE;
3609
		}
3610 3611 3612 3613 3614 3615 3616 3617
		/*
		 * Don't let the exec or mmap label be "*" or "@".
		 */
		skp = smk_fetch(XATTR_NAME_SMACKEXEC, inode, dp);
		if (IS_ERR(skp) || skp == &smack_known_star ||
		    skp == &smack_known_web)
			skp = NULL;
		isp->smk_task = skp;
3618

3619
		skp = smk_fetch(XATTR_NAME_SMACKMMAP, inode, dp);
3620 3621
		if (IS_ERR(skp) || skp == &smack_known_star ||
		    skp == &smack_known_web)
3622 3623
			skp = NULL;
		isp->smk_mmap = skp;
3624

3625 3626 3627 3628 3629
		dput(dp);
		break;
	}

	if (final == NULL)
3630
		isp->smk_inode = ckp;
3631 3632 3633
	else
		isp->smk_inode = final;

3634
	isp->smk_flags |= (SMK_INODE_INSTANT | transflag);
3635 3636 3637 3638 3639 3640 3641 3642 3643 3644 3645 3646 3647 3648 3649 3650 3651 3652

unlockandout:
	mutex_unlock(&isp->smk_lock);
	return;
}

/**
 * smack_getprocattr - Smack process attribute access
 * @p: the object task
 * @name: the name of the attribute in /proc/.../attr
 * @value: where to put the result
 *
 * Places a copy of the task Smack into value
 *
 * Returns the length of the smack label or an error code
 */
static int smack_getprocattr(struct task_struct *p, char *name, char **value)
{
3653
	struct smack_known *skp = smk_of_task_struct(p);
3654 3655 3656 3657 3658 3659
	char *cp;
	int slen;

	if (strcmp(name, "current") != 0)
		return -EINVAL;

3660
	cp = kstrdup(skp->smk_known, GFP_KERNEL);
3661 3662 3663 3664 3665 3666 3667 3668 3669 3670 3671 3672 3673 3674 3675 3676 3677 3678 3679 3680 3681 3682 3683
	if (cp == NULL)
		return -ENOMEM;

	slen = strlen(cp);
	*value = cp;
	return slen;
}

/**
 * smack_setprocattr - Smack process attribute setting
 * @p: the object task
 * @name: the name of the attribute in /proc/.../attr
 * @value: the value to set
 * @size: the size of the value
 *
 * Sets the Smack value of the task. Only setting self
 * is permitted and only with privilege
 *
 * Returns the length of the smack label or an error code
 */
static int smack_setprocattr(struct task_struct *p, char *name,
			     void *value, size_t size)
{
3684
	struct task_smack *tsp = current_security();
D
David Howells 已提交
3685
	struct cred *new;
3686
	struct smack_known *skp;
3687 3688
	struct smack_known_list_elem *sklep;
	int rc;
3689 3690 3691 3692 3693 3694 3695 3696

	/*
	 * Changing another process' Smack value is too dangerous
	 * and supports no sane use case.
	 */
	if (p != current)
		return -EPERM;

3697
	if (!smack_privileged(CAP_MAC_ADMIN) && list_empty(&tsp->smk_relabel))
3698 3699
		return -EPERM;

3700
	if (value == NULL || size == 0 || size >= SMK_LONGLABEL)
3701 3702 3703 3704 3705
		return -EINVAL;

	if (strcmp(name, "current") != 0)
		return -EINVAL;

3706
	skp = smk_import_entry(value, size);
3707 3708
	if (IS_ERR(skp))
		return PTR_ERR(skp);
3709

3710
	/*
3711 3712
	 * No process is ever allowed the web ("@") label
	 * and the star ("*") label.
3713
	 */
3714 3715
	if (skp == &smack_known_web || skp == &smack_known_star)
		return -EINVAL;
3716

3717 3718 3719 3720 3721 3722 3723 3724 3725 3726 3727
	if (!smack_privileged(CAP_MAC_ADMIN)) {
		rc = -EPERM;
		list_for_each_entry(sklep, &tsp->smk_relabel, list)
			if (sklep->smk_label == skp) {
				rc = 0;
				break;
			}
		if (rc)
			return rc;
	}

D
David Howells 已提交
3728
	new = prepare_creds();
3729
	if (new == NULL)
D
David Howells 已提交
3730
		return -ENOMEM;
3731

3732
	tsp = new->security;
3733
	tsp->smk_task = skp;
3734 3735 3736 3737
	/*
	 * process can change its label only once
	 */
	smk_destroy_label_list(&tsp->smk_relabel);
3738

D
David Howells 已提交
3739
	commit_creds(new);
3740 3741 3742 3743 3744
	return size;
}

/**
 * smack_unix_stream_connect - Smack access on UDS
3745 3746
 * @sock: one sock
 * @other: the other sock
3747 3748 3749 3750 3751
 * @newsk: unused
 *
 * Return 0 if a subject with the smack of sock could access
 * an object with the smack of other, otherwise an error code
 */
3752 3753
static int smack_unix_stream_connect(struct sock *sock,
				     struct sock *other, struct sock *newsk)
3754
{
3755
	struct smack_known *skp;
3756
	struct smack_known *okp;
J
James Morris 已提交
3757 3758
	struct socket_smack *ssp = sock->sk_security;
	struct socket_smack *osp = other->sk_security;
3759
	struct socket_smack *nsp = newsk->sk_security;
E
Etienne Basset 已提交
3760
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
3761
	int rc = 0;
3762 3763 3764
#ifdef CONFIG_AUDIT
	struct lsm_network_audit net;
#endif
C
Casey Schaufler 已提交
3765

3766 3767
	if (!smack_privileged(CAP_MAC_OVERRIDE)) {
		skp = ssp->smk_out;
3768
		okp = osp->smk_in;
3769 3770 3771 3772
#ifdef CONFIG_AUDIT
		smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
		smk_ad_setfield_u_net_sk(&ad, other);
#endif
3773 3774
		rc = smk_access(skp, okp, MAY_WRITE, &ad);
		rc = smk_bu_note("UDS connect", skp, okp, MAY_WRITE, rc);
C
Casey Schaufler 已提交
3775
		if (rc == 0) {
3776 3777
			okp = osp->smk_out;
			skp = ssp->smk_in;
3778
			rc = smk_access(okp, skp, MAY_WRITE, &ad);
3779
			rc = smk_bu_note("UDS connect", okp, skp,
C
Casey Schaufler 已提交
3780 3781
						MAY_WRITE, rc);
		}
3782
	}
C
Casey Schaufler 已提交
3783

3784 3785 3786 3787
	/*
	 * Cross reference the peer labels for SO_PEERSEC.
	 */
	if (rc == 0) {
3788 3789
		nsp->smk_packet = ssp->smk_out;
		ssp->smk_packet = osp->smk_out;
3790 3791
	}

C
Casey Schaufler 已提交
3792
	return rc;
3793 3794 3795 3796 3797 3798 3799 3800 3801 3802 3803 3804
}

/**
 * smack_unix_may_send - Smack access on UDS
 * @sock: one socket
 * @other: the other socket
 *
 * Return 0 if a subject with the smack of sock could access
 * an object with the smack of other, otherwise an error code
 */
static int smack_unix_may_send(struct socket *sock, struct socket *other)
{
C
Casey Schaufler 已提交
3805 3806
	struct socket_smack *ssp = sock->sk->sk_security;
	struct socket_smack *osp = other->sk->sk_security;
E
Etienne Basset 已提交
3807
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
3808
	int rc;
3809

3810 3811 3812
#ifdef CONFIG_AUDIT
	struct lsm_network_audit net;

3813
	smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
E
Etienne Basset 已提交
3814
	smk_ad_setfield_u_net_sk(&ad, other->sk);
3815
#endif
C
Casey Schaufler 已提交
3816

3817 3818
	if (smack_privileged(CAP_MAC_OVERRIDE))
		return 0;
C
Casey Schaufler 已提交
3819

3820 3821
	rc = smk_access(ssp->smk_out, osp->smk_in, MAY_WRITE, &ad);
	rc = smk_bu_note("UDS send", ssp->smk_out, osp->smk_in, MAY_WRITE, rc);
C
Casey Schaufler 已提交
3822
	return rc;
3823 3824
}

3825 3826 3827
/**
 * smack_socket_sendmsg - Smack check based on destination host
 * @sock: the socket
3828
 * @msg: the message
3829 3830
 * @size: the size of the message
 *
3831 3832 3833
 * Return 0 if the current subject can write to the destination host.
 * For IPv4 this is only a question if the destination is a single label host.
 * For IPv6 this is a check against the label of the port.
3834 3835 3836 3837 3838
 */
static int smack_socket_sendmsg(struct socket *sock, struct msghdr *msg,
				int size)
{
	struct sockaddr_in *sip = (struct sockaddr_in *) msg->msg_name;
C
Casey Schaufler 已提交
3839
#if IS_ENABLED(CONFIG_IPV6)
3840
	struct sockaddr_in6 *sap = (struct sockaddr_in6 *) msg->msg_name;
C
Casey Schaufler 已提交
3841 3842 3843 3844 3845
#endif
#ifdef SMACK_IPV6_SECMARK_LABELING
	struct socket_smack *ssp = sock->sk->sk_security;
	struct smack_known *rsp;
#endif
3846
	int rc = 0;
3847 3848 3849 3850

	/*
	 * Perfectly reasonable for this to be NULL
	 */
3851
	if (sip == NULL)
3852 3853
		return 0;

3854
	switch (sock->sk->sk_family) {
3855 3856 3857 3858
	case AF_INET:
		rc = smack_netlabel_send(sock->sk, sip);
		break;
	case AF_INET6:
C
Casey Schaufler 已提交
3859 3860 3861 3862 3863 3864 3865
#ifdef SMACK_IPV6_SECMARK_LABELING
		rsp = smack_ipv6host_label(sap);
		if (rsp != NULL)
			rc = smk_ipv6_check(ssp->smk_out, rsp, sap,
						SMK_CONNECTING);
#endif
#ifdef SMACK_IPV6_PORT_LABELING
3866
		rc = smk_ipv6_port_check(sock->sk, sap, SMK_SENDING);
C
Casey Schaufler 已提交
3867
#endif
3868 3869 3870
		break;
	}
	return rc;
3871 3872
}

3873
/**
3874
 * smack_from_secattr - Convert a netlabel attr.mls.lvl/attr.mls.cat pair to smack
3875
 * @sap: netlabel secattr
3876
 * @ssp: socket security information
3877
 *
3878
 * Returns a pointer to a Smack label entry found on the label list.
3879
 */
3880 3881
static struct smack_known *smack_from_secattr(struct netlbl_lsm_secattr *sap,
						struct socket_smack *ssp)
3882
{
3883
	struct smack_known *skp;
3884
	int found = 0;
C
Casey Schaufler 已提交
3885 3886
	int acat;
	int kcat;
3887

3888
	if ((sap->flags & NETLBL_SECATTR_MLS_LVL) != 0) {
3889
		/*
3890
		 * Looks like a CIPSO packet.
3891 3892 3893
		 * If there are flags but no level netlabel isn't
		 * behaving the way we expect it to.
		 *
3894
		 * Look it up in the label table
3895 3896 3897 3898
		 * Without guidance regarding the smack value
		 * for the packet fall back on the network
		 * ambient value.
		 */
3899
		rcu_read_lock();
3900
		list_for_each_entry_rcu(skp, &smack_known_list, list) {
3901
			if (sap->attr.mls.lvl != skp->smk_netlabel.attr.mls.lvl)
3902
				continue;
C
Casey Schaufler 已提交
3903 3904 3905 3906 3907 3908 3909 3910 3911 3912
			/*
			 * Compare the catsets. Use the netlbl APIs.
			 */
			if ((sap->flags & NETLBL_SECATTR_MLS_CAT) == 0) {
				if ((skp->smk_netlabel.flags &
				     NETLBL_SECATTR_MLS_CAT) == 0)
					found = 1;
				break;
			}
			for (acat = -1, kcat = -1; acat == kcat; ) {
3913 3914 3915
				acat = netlbl_catmap_walk(sap->attr.mls.cat,
							  acat + 1);
				kcat = netlbl_catmap_walk(
C
Casey Schaufler 已提交
3916 3917 3918 3919 3920 3921 3922 3923 3924
					skp->smk_netlabel.attr.mls.cat,
					kcat + 1);
				if (acat < 0 || kcat < 0)
					break;
			}
			if (acat == kcat) {
				found = 1;
				break;
			}
3925
		}
3926 3927 3928
		rcu_read_unlock();

		if (found)
3929
			return skp;
3930

3931
		if (ssp != NULL && ssp->smk_in == &smack_known_star)
3932 3933
			return &smack_known_web;
		return &smack_known_star;
3934
	}
3935
	if ((sap->flags & NETLBL_SECATTR_SECID) != 0)
3936 3937 3938
		/*
		 * Looks like a fallback, which gives us a secid.
		 */
3939
		return smack_from_secid(sap->attr.secid);
3940
	/*
3941 3942 3943
	 * Without guidance regarding the smack value
	 * for the packet fall back on the network
	 * ambient value.
3944
	 */
3945
	return smack_net_ambient;
3946 3947
}

3948
#if IS_ENABLED(CONFIG_IPV6)
3949
static int smk_skb_to_addr_ipv6(struct sk_buff *skb, struct sockaddr_in6 *sip)
3950 3951 3952 3953 3954 3955 3956 3957 3958 3959 3960 3961 3962 3963 3964 3965 3966 3967 3968 3969 3970 3971 3972 3973 3974 3975 3976 3977 3978 3979 3980 3981 3982 3983 3984 3985 3986 3987 3988 3989 3990 3991 3992 3993 3994
{
	u8 nexthdr;
	int offset;
	int proto = -EINVAL;
	struct ipv6hdr _ipv6h;
	struct ipv6hdr *ip6;
	__be16 frag_off;
	struct tcphdr _tcph, *th;
	struct udphdr _udph, *uh;
	struct dccp_hdr _dccph, *dh;

	sip->sin6_port = 0;

	offset = skb_network_offset(skb);
	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
	if (ip6 == NULL)
		return -EINVAL;
	sip->sin6_addr = ip6->saddr;

	nexthdr = ip6->nexthdr;
	offset += sizeof(_ipv6h);
	offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
	if (offset < 0)
		return -EINVAL;

	proto = nexthdr;
	switch (proto) {
	case IPPROTO_TCP:
		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
		if (th != NULL)
			sip->sin6_port = th->source;
		break;
	case IPPROTO_UDP:
		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
		if (uh != NULL)
			sip->sin6_port = uh->source;
		break;
	case IPPROTO_DCCP:
		dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
		if (dh != NULL)
			sip->sin6_port = dh->dccph_sport;
		break;
	}
	return proto;
}
3995
#endif /* CONFIG_IPV6 */
3996

3997 3998 3999 4000 4001 4002 4003 4004 4005 4006 4007
/**
 * smack_socket_sock_rcv_skb - Smack packet delivery access check
 * @sk: socket
 * @skb: packet
 *
 * Returns 0 if the packet should be delivered, an error code otherwise
 */
static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
	struct netlbl_lsm_secattr secattr;
	struct socket_smack *ssp = sk->sk_security;
4008
	struct smack_known *skp = NULL;
4009
	int rc = 0;
E
Etienne Basset 已提交
4010
	struct smk_audit_info ad;
4011
#ifdef CONFIG_AUDIT
4012
	struct lsm_network_audit net;
4013
#endif
4014 4015 4016 4017 4018
#if IS_ENABLED(CONFIG_IPV6)
	struct sockaddr_in6 sadd;
	int proto;
#endif /* CONFIG_IPV6 */

4019 4020
	switch (sk->sk_family) {
	case PF_INET:
4021 4022 4023 4024 4025 4026 4027 4028 4029 4030 4031
#ifdef CONFIG_SECURITY_SMACK_NETFILTER
		/*
		 * If there is a secmark use it rather than the CIPSO label.
		 * If there is no secmark fall back to CIPSO.
		 * The secmark is assumed to reflect policy better.
		 */
		if (skb && skb->secmark != 0) {
			skp = smack_from_secid(skb->secmark);
			goto access_check;
		}
#endif /* CONFIG_SECURITY_SMACK_NETFILTER */
4032 4033 4034 4035
		/*
		 * Translate what netlabel gave us.
		 */
		netlbl_secattr_init(&secattr);
4036

4037 4038
		rc = netlbl_skbuff_getattr(skb, sk->sk_family, &secattr);
		if (rc == 0)
4039
			skp = smack_from_secattr(&secattr, ssp);
4040
		else
4041
			skp = smack_net_ambient;
4042

4043
		netlbl_secattr_destroy(&secattr);
4044

4045 4046 4047
#ifdef CONFIG_SECURITY_SMACK_NETFILTER
access_check:
#endif
E
Etienne Basset 已提交
4048
#ifdef CONFIG_AUDIT
4049 4050 4051 4052
		smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
		ad.a.u.net->family = sk->sk_family;
		ad.a.u.net->netif = skb->skb_iif;
		ipv4_skb_to_auditdata(skb, &ad.a, NULL);
E
Etienne Basset 已提交
4053
#endif
4054 4055 4056 4057 4058 4059
		/*
		 * Receiving a packet requires that the other end
		 * be able to write here. Read access is not required.
		 * This is the simplist possible security model
		 * for networking.
		 */
4060 4061
		rc = smk_access(skp, ssp->smk_in, MAY_WRITE, &ad);
		rc = smk_bu_note("IPv4 delivery", skp, ssp->smk_in,
C
Casey Schaufler 已提交
4062
					MAY_WRITE, rc);
4063
		if (rc != 0)
4064
			netlbl_skbuff_err(skb, sk->sk_family, rc, 0);
4065
		break;
4066
#if IS_ENABLED(CONFIG_IPV6)
4067
	case PF_INET6:
4068 4069 4070
		proto = smk_skb_to_addr_ipv6(skb, &sadd);
		if (proto != IPPROTO_UDP && proto != IPPROTO_TCP)
			break;
C
Casey Schaufler 已提交
4071
#ifdef SMACK_IPV6_SECMARK_LABELING
4072 4073
		if (skb && skb->secmark != 0)
			skp = smack_from_secid(skb->secmark);
4074
		else
C
Casey Schaufler 已提交
4075 4076
			skp = smack_ipv6host_label(&sadd);
		if (skp == NULL)
4077 4078 4079 4080 4081 4082 4083 4084 4085 4086
			skp = smack_net_ambient;
#ifdef CONFIG_AUDIT
		smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
		ad.a.u.net->family = sk->sk_family;
		ad.a.u.net->netif = skb->skb_iif;
		ipv6_skb_to_auditdata(skb, &ad.a, NULL);
#endif /* CONFIG_AUDIT */
		rc = smk_access(skp, ssp->smk_in, MAY_WRITE, &ad);
		rc = smk_bu_note("IPv6 delivery", skp, ssp->smk_in,
					MAY_WRITE, rc);
C
Casey Schaufler 已提交
4087 4088
#endif /* SMACK_IPV6_SECMARK_LABELING */
#ifdef SMACK_IPV6_PORT_LABELING
4089
		rc = smk_ipv6_port_check(sk, &sadd, SMK_RECEIVING);
C
Casey Schaufler 已提交
4090
#endif /* SMACK_IPV6_PORT_LABELING */
4091
		break;
4092
#endif /* CONFIG_IPV6 */
4093
	}
4094

4095
	return rc;
4096 4097 4098 4099 4100 4101 4102
}

/**
 * smack_socket_getpeersec_stream - pull in packet label
 * @sock: the socket
 * @optval: user's destination
 * @optlen: size thereof
4103
 * @len: max thereof
4104 4105 4106 4107 4108 4109 4110 4111
 *
 * returns zero on success, an error code otherwise
 */
static int smack_socket_getpeersec_stream(struct socket *sock,
					  char __user *optval,
					  int __user *optlen, unsigned len)
{
	struct socket_smack *ssp;
4112 4113
	char *rcp = "";
	int slen = 1;
4114 4115 4116
	int rc = 0;

	ssp = sock->sk->sk_security;
4117
	if (ssp->smk_packet != NULL) {
4118
		rcp = ssp->smk_packet->smk_known;
4119 4120
		slen = strlen(rcp) + 1;
	}
4121 4122 4123

	if (slen > len)
		rc = -ERANGE;
4124
	else if (copy_to_user(optval, rcp, slen) != 0)
4125 4126 4127 4128 4129 4130 4131 4132 4133 4134 4135
		rc = -EFAULT;

	if (put_user(slen, optlen) != 0)
		rc = -EFAULT;

	return rc;
}


/**
 * smack_socket_getpeersec_dgram - pull in packet label
C
Casey Schaufler 已提交
4136
 * @sock: the peer socket
4137 4138 4139 4140 4141 4142 4143 4144 4145 4146
 * @skb: packet data
 * @secid: pointer to where to put the secid of the packet
 *
 * Sets the netlabel socket state on sk from parent
 */
static int smack_socket_getpeersec_dgram(struct socket *sock,
					 struct sk_buff *skb, u32 *secid)

{
	struct netlbl_lsm_secattr secattr;
4147
	struct socket_smack *ssp = NULL;
4148
	struct smack_known *skp;
C
Casey Schaufler 已提交
4149 4150
	int family = PF_UNSPEC;
	u32 s = 0;	/* 0 is the invalid secid */
4151 4152
	int rc;

C
Casey Schaufler 已提交
4153 4154 4155
	if (skb != NULL) {
		if (skb->protocol == htons(ETH_P_IP))
			family = PF_INET;
4156
#if IS_ENABLED(CONFIG_IPV6)
C
Casey Schaufler 已提交
4157 4158
		else if (skb->protocol == htons(ETH_P_IPV6))
			family = PF_INET6;
4159
#endif /* CONFIG_IPV6 */
4160
	}
C
Casey Schaufler 已提交
4161 4162
	if (family == PF_UNSPEC && sock != NULL)
		family = sock->sk->sk_family;
4163

4164 4165
	switch (family) {
	case PF_UNIX:
4166
		ssp = sock->sk->sk_security;
4167
		s = ssp->smk_out->smk_secid;
4168 4169 4170 4171 4172 4173 4174
		break;
	case PF_INET:
#ifdef CONFIG_SECURITY_SMACK_NETFILTER
		s = skb->secmark;
		if (s != 0)
			break;
#endif
C
Casey Schaufler 已提交
4175 4176 4177
		/*
		 * Translate what netlabel gave us.
		 */
4178 4179
		if (sock != NULL && sock->sk != NULL)
			ssp = sock->sk->sk_security;
C
Casey Schaufler 已提交
4180 4181 4182
		netlbl_secattr_init(&secattr);
		rc = netlbl_skbuff_getattr(skb, family, &secattr);
		if (rc == 0) {
4183 4184
			skp = smack_from_secattr(&secattr, ssp);
			s = skp->smk_secid;
C
Casey Schaufler 已提交
4185 4186
		}
		netlbl_secattr_destroy(&secattr);
4187 4188
		break;
	case PF_INET6:
C
Casey Schaufler 已提交
4189
#ifdef SMACK_IPV6_SECMARK_LABELING
4190
		s = skb->secmark;
C
Casey Schaufler 已提交
4191
#endif
4192
		break;
C
Casey Schaufler 已提交
4193 4194
	}
	*secid = s;
4195 4196 4197 4198 4199 4200
	if (s == 0)
		return -EINVAL;
	return 0;
}

/**
4201 4202 4203
 * smack_sock_graft - Initialize a newly created socket with an existing sock
 * @sk: child sock
 * @parent: parent socket
4204
 *
4205 4206
 * Set the smk_{in,out} state of an existing sock based on the process that
 * is creating the new socket.
4207 4208 4209 4210
 */
static void smack_sock_graft(struct sock *sk, struct socket *parent)
{
	struct socket_smack *ssp;
4211
	struct smack_known *skp = smk_of_current();
4212

4213 4214
	if (sk == NULL ||
	    (sk->sk_family != PF_INET && sk->sk_family != PF_INET6))
4215 4216 4217
		return;

	ssp = sk->sk_security;
4218
	ssp->smk_in = skp;
4219
	ssp->smk_out = skp;
4220
	/* cssp->smk_packet is already set in smack_inet_csk_clone() */
4221 4222 4223 4224 4225 4226 4227 4228 4229 4230 4231 4232 4233 4234
}

/**
 * smack_inet_conn_request - Smack access check on connect
 * @sk: socket involved
 * @skb: packet
 * @req: unused
 *
 * Returns 0 if a task with the packet label could write to
 * the socket, otherwise an error code
 */
static int smack_inet_conn_request(struct sock *sk, struct sk_buff *skb,
				   struct request_sock *req)
{
4235
	u16 family = sk->sk_family;
4236
	struct smack_known *skp;
4237
	struct socket_smack *ssp = sk->sk_security;
4238 4239 4240
	struct netlbl_lsm_secattr secattr;
	struct sockaddr_in addr;
	struct iphdr *hdr;
4241
	struct smack_known *hskp;
4242
	int rc;
E
Etienne Basset 已提交
4243
	struct smk_audit_info ad;
4244
#ifdef CONFIG_AUDIT
4245
	struct lsm_network_audit net;
4246
#endif
4247

4248
#if IS_ENABLED(CONFIG_IPV6)
4249 4250 4251 4252 4253 4254 4255 4256 4257 4258 4259
	if (family == PF_INET6) {
		/*
		 * Handle mapped IPv4 packets arriving
		 * via IPv6 sockets. Don't set up netlabel
		 * processing on IPv6.
		 */
		if (skb->protocol == htons(ETH_P_IP))
			family = PF_INET;
		else
			return 0;
	}
4260
#endif /* CONFIG_IPV6 */
4261

C
Casey Schaufler 已提交
4262 4263 4264 4265 4266 4267 4268 4269 4270 4271 4272 4273
#ifdef CONFIG_SECURITY_SMACK_NETFILTER
	/*
	 * If there is a secmark use it rather than the CIPSO label.
	 * If there is no secmark fall back to CIPSO.
	 * The secmark is assumed to reflect policy better.
	 */
	if (skb && skb->secmark != 0) {
		skp = smack_from_secid(skb->secmark);
		goto access_check;
	}
#endif /* CONFIG_SECURITY_SMACK_NETFILTER */

4274 4275
	netlbl_secattr_init(&secattr);
	rc = netlbl_skbuff_getattr(skb, family, &secattr);
4276
	if (rc == 0)
4277
		skp = smack_from_secattr(&secattr, ssp);
4278
	else
4279
		skp = &smack_known_huh;
4280 4281
	netlbl_secattr_destroy(&secattr);

C
Casey Schaufler 已提交
4282 4283 4284 4285
#ifdef CONFIG_SECURITY_SMACK_NETFILTER
access_check:
#endif

E
Etienne Basset 已提交
4286
#ifdef CONFIG_AUDIT
4287 4288 4289
	smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
	ad.a.u.net->family = family;
	ad.a.u.net->netif = skb->skb_iif;
E
Etienne Basset 已提交
4290 4291
	ipv4_skb_to_auditdata(skb, &ad.a, NULL);
#endif
4292
	/*
4293 4294
	 * Receiving a packet requires that the other end be able to write
	 * here. Read access is not required.
4295
	 */
4296 4297
	rc = smk_access(skp, ssp->smk_in, MAY_WRITE, &ad);
	rc = smk_bu_note("IPv4 connect", skp, ssp->smk_in, MAY_WRITE, rc);
4298 4299 4300 4301 4302 4303 4304
	if (rc != 0)
		return rc;

	/*
	 * Save the peer's label in the request_sock so we can later setup
	 * smk_packet in the child socket so that SO_PEERCRED can report it.
	 */
4305
	req->peer_secid = skp->smk_secid;
4306 4307 4308 4309

	/*
	 * We need to decide if we want to label the incoming connection here
	 * if we do we only need to label the request_sock and the stack will
L
Lucas De Marchi 已提交
4310
	 * propagate the wire-label to the sock when it is created.
4311 4312 4313 4314
	 */
	hdr = ip_hdr(skb);
	addr.sin_addr.s_addr = hdr->saddr;
	rcu_read_lock();
C
Casey Schaufler 已提交
4315
	hskp = smack_ipv4host_label(&addr);
4316 4317
	rcu_read_unlock();

4318
	if (hskp == NULL)
4319
		rc = netlbl_req_setattr(req, &skp->smk_netlabel);
4320
	else
4321
		netlbl_req_delattr(req);
4322 4323 4324 4325

	return rc;
}

4326 4327 4328 4329 4330 4331 4332 4333 4334 4335 4336
/**
 * smack_inet_csk_clone - Copy the connection information to the new socket
 * @sk: the new socket
 * @req: the connection's request_sock
 *
 * Transfer the connection's peer label to the newly created socket.
 */
static void smack_inet_csk_clone(struct sock *sk,
				 const struct request_sock *req)
{
	struct socket_smack *ssp = sk->sk_security;
4337
	struct smack_known *skp;
4338

4339 4340
	if (req->peer_secid != 0) {
		skp = smack_from_secid(req->peer_secid);
4341
		ssp->smk_packet = skp;
4342
	} else
4343
		ssp->smk_packet = NULL;
4344 4345
}

4346 4347 4348 4349 4350 4351 4352 4353 4354 4355 4356 4357
/*
 * Key management security hooks
 *
 * Casey has not tested key support very heavily.
 * The permission check is most likely too restrictive.
 * If you care about keys please have a look.
 */
#ifdef CONFIG_KEYS

/**
 * smack_key_alloc - Set the key security blob
 * @key: object
D
David Howells 已提交
4358
 * @cred: the credentials to use
4359 4360 4361 4362 4363 4364
 * @flags: unused
 *
 * No allocation required
 *
 * Returns 0
 */
D
David Howells 已提交
4365
static int smack_key_alloc(struct key *key, const struct cred *cred,
4366 4367
			   unsigned long flags)
{
4368 4369
	struct smack_known *skp = smk_of_task(cred->security);

4370
	key->security = skp;
4371 4372 4373 4374 4375 4376 4377 4378 4379 4380 4381 4382 4383 4384
	return 0;
}

/**
 * smack_key_free - Clear the key security blob
 * @key: the object
 *
 * Clear the blob pointer
 */
static void smack_key_free(struct key *key)
{
	key->security = NULL;
}

4385
/**
4386 4387
 * smack_key_permission - Smack access on a key
 * @key_ref: gets to the object
D
David Howells 已提交
4388
 * @cred: the credentials to use
4389
 * @perm: requested key permissions
4390 4391 4392 4393 4394
 *
 * Return 0 if the task has read and write to the object,
 * an error code otherwise
 */
static int smack_key_permission(key_ref_t key_ref,
4395
				const struct cred *cred, unsigned perm)
4396 4397
{
	struct key *keyp;
E
Etienne Basset 已提交
4398
	struct smk_audit_info ad;
4399
	struct smack_known *tkp = smk_of_task(cred->security);
4400
	int request = 0;
C
Casey Schaufler 已提交
4401
	int rc;
4402 4403 4404 4405 4406 4407 4408 4409 4410 4411 4412 4413 4414

	keyp = key_ref_to_ptr(key_ref);
	if (keyp == NULL)
		return -EINVAL;
	/*
	 * If the key hasn't been initialized give it access so that
	 * it may do so.
	 */
	if (keyp->security == NULL)
		return 0;
	/*
	 * This should not occur
	 */
4415
	if (tkp == NULL)
4416
		return -EACCES;
E
Etienne Basset 已提交
4417 4418 4419 4420 4421
#ifdef CONFIG_AUDIT
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_KEY);
	ad.a.u.key_struct.key = keyp->serial;
	ad.a.u.key_struct.key_desc = keyp->description;
#endif
4422 4423 4424 4425
	if (perm & KEY_NEED_READ)
		request = MAY_READ;
	if (perm & (KEY_NEED_WRITE | KEY_NEED_LINK | KEY_NEED_SETATTR))
		request = MAY_WRITE;
C
Casey Schaufler 已提交
4426 4427 4428
	rc = smk_access(tkp, keyp->security, request, &ad);
	rc = smk_bu_note("key access", tkp, keyp->security, request, rc);
	return rc;
4429
}
4430 4431 4432 4433 4434 4435 4436 4437 4438 4439 4440 4441 4442 4443 4444 4445 4446 4447 4448 4449 4450 4451 4452 4453 4454 4455 4456 4457 4458 4459

/*
 * smack_key_getsecurity - Smack label tagging the key
 * @key points to the key to be queried
 * @_buffer points to a pointer that should be set to point to the
 * resulting string (if no label or an error occurs).
 * Return the length of the string (including terminating NUL) or -ve if
 * an error.
 * May also return 0 (and a NULL buffer pointer) if there is no label.
 */
static int smack_key_getsecurity(struct key *key, char **_buffer)
{
	struct smack_known *skp = key->security;
	size_t length;
	char *copy;

	if (key->security == NULL) {
		*_buffer = NULL;
		return 0;
	}

	copy = kstrdup(skp->smk_known, GFP_KERNEL);
	if (copy == NULL)
		return -ENOMEM;
	length = strlen(copy) + 1;

	*_buffer = copy;
	return length;
}

4460 4461
#endif /* CONFIG_KEYS */

4462 4463 4464 4465 4466 4467 4468 4469 4470 4471 4472 4473 4474 4475 4476 4477 4478 4479 4480 4481 4482 4483 4484 4485 4486 4487 4488
/*
 * Smack Audit hooks
 *
 * Audit requires a unique representation of each Smack specific
 * rule. This unique representation is used to distinguish the
 * object to be audited from remaining kernel objects and also
 * works as a glue between the audit hooks.
 *
 * Since repository entries are added but never deleted, we'll use
 * the smack_known label address related to the given audit rule as
 * the needed unique representation. This also better fits the smack
 * model where nearly everything is a label.
 */
#ifdef CONFIG_AUDIT

/**
 * smack_audit_rule_init - Initialize a smack audit rule
 * @field: audit rule fields given from user-space (audit.h)
 * @op: required testing operator (=, !=, >, <, ...)
 * @rulestr: smack label to be audited
 * @vrule: pointer to save our own audit rule representation
 *
 * Prepare to audit cases where (@field @op @rulestr) is true.
 * The label to be audited is created if necessay.
 */
static int smack_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
{
4489
	struct smack_known *skp;
4490 4491 4492 4493 4494 4495
	char **rule = (char **)vrule;
	*rule = NULL;

	if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
		return -EINVAL;

4496
	if (op != Audit_equal && op != Audit_not_equal)
4497 4498
		return -EINVAL;

4499
	skp = smk_import_entry(rulestr, 0);
4500 4501 4502 4503
	if (IS_ERR(skp))
		return PTR_ERR(skp);

	*rule = skp->smk_known;
4504 4505 4506 4507 4508 4509 4510 4511 4512 4513 4514 4515 4516 4517 4518 4519 4520 4521 4522 4523 4524 4525 4526 4527 4528 4529 4530 4531 4532 4533 4534 4535 4536 4537 4538 4539 4540 4541 4542 4543 4544

	return 0;
}

/**
 * smack_audit_rule_known - Distinguish Smack audit rules
 * @krule: rule of interest, in Audit kernel representation format
 *
 * This is used to filter Smack rules from remaining Audit ones.
 * If it's proved that this rule belongs to us, the
 * audit_rule_match hook will be called to do the final judgement.
 */
static int smack_audit_rule_known(struct audit_krule *krule)
{
	struct audit_field *f;
	int i;

	for (i = 0; i < krule->field_count; i++) {
		f = &krule->fields[i];

		if (f->type == AUDIT_SUBJ_USER || f->type == AUDIT_OBJ_USER)
			return 1;
	}

	return 0;
}

/**
 * smack_audit_rule_match - Audit given object ?
 * @secid: security id for identifying the object to test
 * @field: audit rule flags given from user-space
 * @op: required testing operator
 * @vrule: smack internal rule presentation
 * @actx: audit context associated with the check
 *
 * The core Audit hook. It's used to take the decision of
 * whether to audit or not to audit a given object.
 */
static int smack_audit_rule_match(u32 secid, u32 field, u32 op, void *vrule,
				  struct audit_context *actx)
{
4545
	struct smack_known *skp;
4546 4547
	char *rule = vrule;

4548 4549
	if (unlikely(!rule)) {
		WARN_ONCE(1, "Smack: missing rule\n");
4550 4551 4552 4553 4554 4555
		return -ENOENT;
	}

	if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
		return 0;

4556
	skp = smack_from_secid(secid);
4557 4558 4559 4560 4561 4562

	/*
	 * No need to do string comparisons. If a match occurs,
	 * both pointers will point to the same smack_known
	 * label.
	 */
4563
	if (op == Audit_equal)
4564
		return (rule == skp->smk_known);
4565
	if (op == Audit_not_equal)
4566
		return (rule != skp->smk_known);
4567 4568 4569 4570

	return 0;
}

C
Casey Schaufler 已提交
4571 4572
/*
 * There is no need for a smack_audit_rule_free hook.
4573 4574 4575 4576 4577
 * No memory was allocated.
 */

#endif /* CONFIG_AUDIT */

4578 4579 4580 4581 4582 4583 4584 4585 4586 4587
/**
 * smack_ismaclabel - check if xattr @name references a smack MAC label
 * @name: Full xattr name to check.
 */
static int smack_ismaclabel(const char *name)
{
	return (strcmp(name, XATTR_SMACK_SUFFIX) == 0);
}


4588
/**
4589 4590 4591 4592 4593 4594 4595 4596 4597
 * smack_secid_to_secctx - return the smack label for a secid
 * @secid: incoming integer
 * @secdata: destination
 * @seclen: how long it is
 *
 * Exists for networking code.
 */
static int smack_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
{
4598
	struct smack_known *skp = smack_from_secid(secid);
4599

4600
	if (secdata)
4601 4602
		*secdata = skp->smk_known;
	*seclen = strlen(skp->smk_known);
4603 4604 4605
	return 0;
}

4606
/**
4607 4608 4609 4610 4611 4612 4613
 * smack_secctx_to_secid - return the secid for a smack label
 * @secdata: smack label
 * @seclen: how long result is
 * @secid: outgoing integer
 *
 * Exists for audit and networking code.
 */
4614
static int smack_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
4615
{
4616 4617 4618 4619 4620 4621
	struct smack_known *skp = smk_find_entry(secdata);

	if (skp)
		*secid = skp->smk_secid;
	else
		*secid = 0;
4622 4623 4624
	return 0;
}

C
Casey Schaufler 已提交
4625 4626 4627 4628
/*
 * There used to be a smack_release_secctx hook
 * that did nothing back when hooks were in a vector.
 * Now that there's a list such a hook adds cost.
4629 4630
 */

4631 4632 4633 4634 4635 4636 4637 4638 4639 4640 4641 4642 4643 4644 4645 4646 4647 4648 4649 4650 4651
static int smack_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
{
	return smack_inode_setsecurity(inode, XATTR_SMACK_SUFFIX, ctx, ctxlen, 0);
}

static int smack_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
{
	return __vfs_setxattr_noperm(dentry, XATTR_NAME_SMACK, ctx, ctxlen, 0);
}

static int smack_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
{
	int len = 0;
	len = smack_inode_getsecurity(inode, XATTR_SMACK_SUFFIX, ctx, true);

	if (len < 0)
		return len;
	*ctxlen = len;
	return 0;
}

4652
static struct security_hook_list smack_hooks[] = {
4653 4654 4655 4656 4657 4658 4659 4660 4661
	LSM_HOOK_INIT(ptrace_access_check, smack_ptrace_access_check),
	LSM_HOOK_INIT(ptrace_traceme, smack_ptrace_traceme),
	LSM_HOOK_INIT(syslog, smack_syslog),

	LSM_HOOK_INIT(sb_alloc_security, smack_sb_alloc_security),
	LSM_HOOK_INIT(sb_free_security, smack_sb_free_security),
	LSM_HOOK_INIT(sb_copy_data, smack_sb_copy_data),
	LSM_HOOK_INIT(sb_kern_mount, smack_sb_kern_mount),
	LSM_HOOK_INIT(sb_statfs, smack_sb_statfs),
4662 4663
	LSM_HOOK_INIT(sb_set_mnt_opts, smack_set_mnt_opts),
	LSM_HOOK_INIT(sb_parse_opts_str, smack_parse_opts_str),
4664 4665 4666 4667 4668 4669 4670 4671 4672 4673 4674 4675 4676 4677 4678 4679 4680 4681 4682 4683 4684 4685 4686 4687 4688 4689 4690 4691 4692 4693 4694 4695 4696 4697 4698 4699 4700 4701 4702 4703 4704 4705 4706 4707 4708 4709 4710 4711 4712 4713 4714 4715 4716 4717 4718 4719 4720 4721 4722 4723 4724 4725 4726 4727 4728 4729 4730 4731 4732 4733 4734 4735 4736 4737 4738 4739 4740 4741 4742 4743 4744 4745 4746 4747 4748 4749 4750 4751 4752 4753 4754

	LSM_HOOK_INIT(bprm_set_creds, smack_bprm_set_creds),
	LSM_HOOK_INIT(bprm_committing_creds, smack_bprm_committing_creds),
	LSM_HOOK_INIT(bprm_secureexec, smack_bprm_secureexec),

	LSM_HOOK_INIT(inode_alloc_security, smack_inode_alloc_security),
	LSM_HOOK_INIT(inode_free_security, smack_inode_free_security),
	LSM_HOOK_INIT(inode_init_security, smack_inode_init_security),
	LSM_HOOK_INIT(inode_link, smack_inode_link),
	LSM_HOOK_INIT(inode_unlink, smack_inode_unlink),
	LSM_HOOK_INIT(inode_rmdir, smack_inode_rmdir),
	LSM_HOOK_INIT(inode_rename, smack_inode_rename),
	LSM_HOOK_INIT(inode_permission, smack_inode_permission),
	LSM_HOOK_INIT(inode_setattr, smack_inode_setattr),
	LSM_HOOK_INIT(inode_getattr, smack_inode_getattr),
	LSM_HOOK_INIT(inode_setxattr, smack_inode_setxattr),
	LSM_HOOK_INIT(inode_post_setxattr, smack_inode_post_setxattr),
	LSM_HOOK_INIT(inode_getxattr, smack_inode_getxattr),
	LSM_HOOK_INIT(inode_removexattr, smack_inode_removexattr),
	LSM_HOOK_INIT(inode_getsecurity, smack_inode_getsecurity),
	LSM_HOOK_INIT(inode_setsecurity, smack_inode_setsecurity),
	LSM_HOOK_INIT(inode_listsecurity, smack_inode_listsecurity),
	LSM_HOOK_INIT(inode_getsecid, smack_inode_getsecid),

	LSM_HOOK_INIT(file_alloc_security, smack_file_alloc_security),
	LSM_HOOK_INIT(file_free_security, smack_file_free_security),
	LSM_HOOK_INIT(file_ioctl, smack_file_ioctl),
	LSM_HOOK_INIT(file_lock, smack_file_lock),
	LSM_HOOK_INIT(file_fcntl, smack_file_fcntl),
	LSM_HOOK_INIT(mmap_file, smack_mmap_file),
	LSM_HOOK_INIT(mmap_addr, cap_mmap_addr),
	LSM_HOOK_INIT(file_set_fowner, smack_file_set_fowner),
	LSM_HOOK_INIT(file_send_sigiotask, smack_file_send_sigiotask),
	LSM_HOOK_INIT(file_receive, smack_file_receive),

	LSM_HOOK_INIT(file_open, smack_file_open),

	LSM_HOOK_INIT(cred_alloc_blank, smack_cred_alloc_blank),
	LSM_HOOK_INIT(cred_free, smack_cred_free),
	LSM_HOOK_INIT(cred_prepare, smack_cred_prepare),
	LSM_HOOK_INIT(cred_transfer, smack_cred_transfer),
	LSM_HOOK_INIT(kernel_act_as, smack_kernel_act_as),
	LSM_HOOK_INIT(kernel_create_files_as, smack_kernel_create_files_as),
	LSM_HOOK_INIT(task_setpgid, smack_task_setpgid),
	LSM_HOOK_INIT(task_getpgid, smack_task_getpgid),
	LSM_HOOK_INIT(task_getsid, smack_task_getsid),
	LSM_HOOK_INIT(task_getsecid, smack_task_getsecid),
	LSM_HOOK_INIT(task_setnice, smack_task_setnice),
	LSM_HOOK_INIT(task_setioprio, smack_task_setioprio),
	LSM_HOOK_INIT(task_getioprio, smack_task_getioprio),
	LSM_HOOK_INIT(task_setscheduler, smack_task_setscheduler),
	LSM_HOOK_INIT(task_getscheduler, smack_task_getscheduler),
	LSM_HOOK_INIT(task_movememory, smack_task_movememory),
	LSM_HOOK_INIT(task_kill, smack_task_kill),
	LSM_HOOK_INIT(task_wait, smack_task_wait),
	LSM_HOOK_INIT(task_to_inode, smack_task_to_inode),

	LSM_HOOK_INIT(ipc_permission, smack_ipc_permission),
	LSM_HOOK_INIT(ipc_getsecid, smack_ipc_getsecid),

	LSM_HOOK_INIT(msg_msg_alloc_security, smack_msg_msg_alloc_security),
	LSM_HOOK_INIT(msg_msg_free_security, smack_msg_msg_free_security),

	LSM_HOOK_INIT(msg_queue_alloc_security, smack_msg_queue_alloc_security),
	LSM_HOOK_INIT(msg_queue_free_security, smack_msg_queue_free_security),
	LSM_HOOK_INIT(msg_queue_associate, smack_msg_queue_associate),
	LSM_HOOK_INIT(msg_queue_msgctl, smack_msg_queue_msgctl),
	LSM_HOOK_INIT(msg_queue_msgsnd, smack_msg_queue_msgsnd),
	LSM_HOOK_INIT(msg_queue_msgrcv, smack_msg_queue_msgrcv),

	LSM_HOOK_INIT(shm_alloc_security, smack_shm_alloc_security),
	LSM_HOOK_INIT(shm_free_security, smack_shm_free_security),
	LSM_HOOK_INIT(shm_associate, smack_shm_associate),
	LSM_HOOK_INIT(shm_shmctl, smack_shm_shmctl),
	LSM_HOOK_INIT(shm_shmat, smack_shm_shmat),

	LSM_HOOK_INIT(sem_alloc_security, smack_sem_alloc_security),
	LSM_HOOK_INIT(sem_free_security, smack_sem_free_security),
	LSM_HOOK_INIT(sem_associate, smack_sem_associate),
	LSM_HOOK_INIT(sem_semctl, smack_sem_semctl),
	LSM_HOOK_INIT(sem_semop, smack_sem_semop),

	LSM_HOOK_INIT(d_instantiate, smack_d_instantiate),

	LSM_HOOK_INIT(getprocattr, smack_getprocattr),
	LSM_HOOK_INIT(setprocattr, smack_setprocattr),

	LSM_HOOK_INIT(unix_stream_connect, smack_unix_stream_connect),
	LSM_HOOK_INIT(unix_may_send, smack_unix_may_send),

	LSM_HOOK_INIT(socket_post_create, smack_socket_post_create),
C
Casey Schaufler 已提交
4755
#ifdef SMACK_IPV6_PORT_LABELING
4756
	LSM_HOOK_INIT(socket_bind, smack_socket_bind),
C
Casey Schaufler 已提交
4757
#endif
4758 4759 4760 4761 4762 4763 4764 4765 4766 4767
	LSM_HOOK_INIT(socket_connect, smack_socket_connect),
	LSM_HOOK_INIT(socket_sendmsg, smack_socket_sendmsg),
	LSM_HOOK_INIT(socket_sock_rcv_skb, smack_socket_sock_rcv_skb),
	LSM_HOOK_INIT(socket_getpeersec_stream, smack_socket_getpeersec_stream),
	LSM_HOOK_INIT(socket_getpeersec_dgram, smack_socket_getpeersec_dgram),
	LSM_HOOK_INIT(sk_alloc_security, smack_sk_alloc_security),
	LSM_HOOK_INIT(sk_free_security, smack_sk_free_security),
	LSM_HOOK_INIT(sock_graft, smack_sock_graft),
	LSM_HOOK_INIT(inet_conn_request, smack_inet_conn_request),
	LSM_HOOK_INIT(inet_csk_clone, smack_inet_csk_clone),
4768

4769 4770
 /* key management security hooks */
#ifdef CONFIG_KEYS
4771 4772 4773 4774
	LSM_HOOK_INIT(key_alloc, smack_key_alloc),
	LSM_HOOK_INIT(key_free, smack_key_free),
	LSM_HOOK_INIT(key_permission, smack_key_permission),
	LSM_HOOK_INIT(key_getsecurity, smack_key_getsecurity),
4775
#endif /* CONFIG_KEYS */
4776 4777 4778

 /* Audit hooks */
#ifdef CONFIG_AUDIT
4779 4780 4781
	LSM_HOOK_INIT(audit_rule_init, smack_audit_rule_init),
	LSM_HOOK_INIT(audit_rule_known, smack_audit_rule_known),
	LSM_HOOK_INIT(audit_rule_match, smack_audit_rule_match),
4782 4783
#endif /* CONFIG_AUDIT */

4784 4785 4786 4787 4788 4789
	LSM_HOOK_INIT(ismaclabel, smack_ismaclabel),
	LSM_HOOK_INIT(secid_to_secctx, smack_secid_to_secctx),
	LSM_HOOK_INIT(secctx_to_secid, smack_secctx_to_secid),
	LSM_HOOK_INIT(inode_notifysecctx, smack_inode_notifysecctx),
	LSM_HOOK_INIT(inode_setsecctx, smack_inode_setsecctx),
	LSM_HOOK_INIT(inode_getsecctx, smack_inode_getsecctx),
4790 4791
};

4792

4793
static __init void init_smack_known_list(void)
4794
{
4795 4796 4797 4798 4799 4800 4801 4802 4803 4804 4805 4806 4807 4808 4809 4810 4811 4812 4813
	/*
	 * Initialize rule list locks
	 */
	mutex_init(&smack_known_huh.smk_rules_lock);
	mutex_init(&smack_known_hat.smk_rules_lock);
	mutex_init(&smack_known_floor.smk_rules_lock);
	mutex_init(&smack_known_star.smk_rules_lock);
	mutex_init(&smack_known_web.smk_rules_lock);
	/*
	 * Initialize rule lists
	 */
	INIT_LIST_HEAD(&smack_known_huh.smk_rules);
	INIT_LIST_HEAD(&smack_known_hat.smk_rules);
	INIT_LIST_HEAD(&smack_known_star.smk_rules);
	INIT_LIST_HEAD(&smack_known_floor.smk_rules);
	INIT_LIST_HEAD(&smack_known_web.smk_rules);
	/*
	 * Create the known labels list
	 */
4814 4815 4816 4817 4818
	smk_insert_entry(&smack_known_huh);
	smk_insert_entry(&smack_known_hat);
	smk_insert_entry(&smack_known_star);
	smk_insert_entry(&smack_known_floor);
	smk_insert_entry(&smack_known_web);
4819 4820
}

4821 4822 4823 4824 4825 4826 4827
/**
 * smack_init - initialize the smack system
 *
 * Returns 0
 */
static __init int smack_init(void)
{
D
David Howells 已提交
4828
	struct cred *cred;
4829
	struct task_smack *tsp;
D
David Howells 已提交
4830

C
Casey Schaufler 已提交
4831
	if (!security_module_enable("smack"))
4832 4833
		return 0;

4834 4835 4836 4837
	smack_inode_cache = KMEM_CACHE(inode_smack, 0);
	if (!smack_inode_cache)
		return -ENOMEM;

4838 4839
	tsp = new_task_smack(&smack_known_floor, &smack_known_floor,
				GFP_KERNEL);
4840 4841
	if (tsp == NULL) {
		kmem_cache_destroy(smack_inode_cache);
4842
		return -ENOMEM;
4843
	}
4844

4845 4846
	smack_enabled = 1;

C
Casey Schaufler 已提交
4847 4848 4849 4850 4851 4852 4853 4854 4855 4856
	pr_info("Smack:  Initializing.\n");
#ifdef CONFIG_SECURITY_SMACK_NETFILTER
	pr_info("Smack:  Netfilter enabled.\n");
#endif
#ifdef SMACK_IPV6_PORT_LABELING
	pr_info("Smack:  IPv6 port labeling enabled.\n");
#endif
#ifdef SMACK_IPV6_SECMARK_LABELING
	pr_info("Smack:  IPv6 Netfilter enabled.\n");
#endif
4857 4858 4859 4860

	/*
	 * Set the security state for the initial task.
	 */
D
David Howells 已提交
4861
	cred = (struct cred *) current->cred;
4862
	cred->security = tsp;
4863

4864 4865
	/* initialize the smack_known_list */
	init_smack_known_list();
4866 4867 4868 4869

	/*
	 * Register with LSM
	 */
C
Casey Schaufler 已提交
4870
	security_add_hooks(smack_hooks, ARRAY_SIZE(smack_hooks));
4871 4872 4873 4874 4875 4876 4877 4878 4879

	return 0;
}

/*
 * Smack requires early initialization in order to label
 * all processes and objects when they are created.
 */
security_initcall(smack_init);