smack_lsm.c 100.8 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 "smack.h"

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#define task_security(task)	(task_cred_xxx((task), security))

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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

LIST_HEAD(smk_ipv6_port_list);
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static struct kmem_cache *smack_inode_cache;
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#ifdef CONFIG_SECURITY_SMACK_BRINGUP
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;

	smk_bu_mode(mode, acc);
	pr_info("Smack Bringup: (%s %s %s) %s\n",
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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;

	smk_bu_mode(mode, acc);
	pr_info("Smack Bringup: (%s %s %s) %s %s\n",
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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();
	struct task_smack *otsp = task_security(otp);
	char acc[SMK_NUM_ACCESS_TYPE + 1];

	if (rc <= 0)
		return rc;

	smk_bu_mode(mode, acc);
	pr_info("Smack Bringup: (%s %s %s) %s to %s\n",
		tsp->smk_task->smk_known, otsp->smk_task->smk_known, acc,
		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();
	char acc[SMK_NUM_ACCESS_TYPE + 1];

	if (rc <= 0)
		return rc;

	smk_bu_mode(mode, acc);
	pr_info("Smack Bringup: (%s %s %s) inode=(%s %ld) %s\n",
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		tsp->smk_task->smk_known, smk_of_inode(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;
	struct inode *inode = file->f_inode;
	char acc[SMK_NUM_ACCESS_TYPE + 1];

	if (rc <= 0)
		return rc;

	smk_bu_mode(mode, acc);
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	pr_info("Smack Bringup: (%s %s %s) file=(%s %ld %pD) %s\n",
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		sskp->smk_known, (char *)file->f_security, 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;
	struct inode *inode = file->f_inode;
	char acc[SMK_NUM_ACCESS_TYPE + 1];

	if (rc <= 0)
		return rc;

	smk_bu_mode(mode, acc);
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	pr_info("Smack Bringup: (%s %s %s) file=(%s %ld %pD) %s\n",
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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.
 * @ip: a pointer to the inode
 * @dp: a pointer to the dentry
 *
 * Returns a pointer to the master list entry for the Smack label
 * or NULL if there was no label to fetch.
 */
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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_op->getxattr == NULL)
		return NULL;

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	buffer = kzalloc(SMK_LONGLABEL, GFP_KERNEL);
	if (buffer == NULL)
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		return NULL;

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	rc = ip->i_op->getxattr(dp, name, buffer, SMK_LONGLABEL);
	if (rc > 0)
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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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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
 * @smack: a pointer to the Smack label to use in the blob
 *
 * 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);
	mutex_init(&tsp->smk_rules_lock);

	return tsp;
}

/**
 * smk_copy_rules - copy a rule set
 * @nhead - new rules header pointer
 * @ohead - old rules header pointer
 *
 * 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;

	INIT_LIST_HEAD(nhead);

	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_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)
{
	switch (mode) {
	case PTRACE_MODE_READ:
		return MAY_READ;
	case PTRACE_MODE_ATTACH:
		return MAY_READWRITE;
	}

	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;
	}

	tsp = task_security(tracer);
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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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		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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	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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{
	int rc;
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	struct smack_known *skp;
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	rc = cap_ptrace_access_check(ctp, mode);
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	if (rc != 0)
		return rc;

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	skp = smk_of_task(task_security(ctp));
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	rc = smk_ptrace_rule_check(current, skp, mode, __func__);
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	return rc;
}

/**
 * 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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	rc = cap_ptrace_traceme(ptp);
	if (rc != 0)
		return rc;
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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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	/*
	 * smk_initialized will be zero from kzalloc.
	 */
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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;
}

/**
 * smack_sb_kern_mount - Smack specific mount processing
 * @sb: the file system superblock
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 * @flags: the mount flags
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 * @data: the smack mount options
 *
 * Returns 0 on success, an error code on failure
 */
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static int smack_sb_kern_mount(struct super_block *sb, int flags, void *data)
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{
	struct dentry *root = sb->s_root;
	struct inode *inode = root->d_inode;
	struct superblock_smack *sp = sb->s_security;
	struct inode_smack *isp;
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	struct smack_known *skp;
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	char *op;
	char *commap;
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	int transmute = 0;
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	int specified = 0;
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	if (sp->smk_initialized)
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		return 0;
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	sp->smk_initialized = 1;

	for (op = data; op != NULL; op = commap) {
		commap = strchr(op, ',');
		if (commap != NULL)
			*commap++ = '\0';

		if (strncmp(op, SMK_FSHAT, strlen(SMK_FSHAT)) == 0) {
			op += strlen(SMK_FSHAT);
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			skp = smk_import_entry(op, 0);
			if (skp != NULL) {
				sp->smk_hat = skp;
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				specified = 1;
			}
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		} else if (strncmp(op, SMK_FSFLOOR, strlen(SMK_FSFLOOR)) == 0) {
			op += strlen(SMK_FSFLOOR);
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			skp = smk_import_entry(op, 0);
			if (skp != NULL) {
				sp->smk_floor = skp;
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				specified = 1;
			}
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		} else if (strncmp(op, SMK_FSDEFAULT,
				   strlen(SMK_FSDEFAULT)) == 0) {
			op += strlen(SMK_FSDEFAULT);
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			skp = smk_import_entry(op, 0);
			if (skp != NULL) {
				sp->smk_default = skp;
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				specified = 1;
			}
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		} else if (strncmp(op, SMK_FSROOT, strlen(SMK_FSROOT)) == 0) {
			op += strlen(SMK_FSROOT);
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			skp = smk_import_entry(op, 0);
			if (skp != NULL) {
				sp->smk_root = skp;
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				specified = 1;
			}
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		} else if (strncmp(op, SMK_FSTRANS, strlen(SMK_FSTRANS)) == 0) {
			op += strlen(SMK_FSTRANS);
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			skp = smk_import_entry(op, 0);
			if (skp != NULL) {
				sp->smk_root = skp;
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				transmute = 1;
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				specified = 1;
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			}
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		}
	}

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	if (!smack_privileged(CAP_MAC_ADMIN)) {
		/*
		 * Unprivileged mounts don't get to specify Smack values.
		 */
		if (specified)
			return -EPERM;
		/*
		 * Unprivileged mounts get root and default from the caller.
		 */
		skp = smk_of_current();
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		sp->smk_root = skp;
		sp->smk_default = skp;
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	}
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	/*
	 * Initialize the root inode.
	 */
	isp = inode->i_security;
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	if (isp == NULL) {
		isp = new_inode_smack(sp->smk_root);
		if (isp == NULL)
			return -ENOMEM;
		inode->i_security = isp;
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	} else
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		isp->smk_inode = sp->smk_root;

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

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	return 0;
}

/**
 * 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;
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	int rc;
	struct smk_audit_info ad;

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	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
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	smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
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	rc = smk_curacc(sbp->smk_floor, MAY_READ, &ad);
C
Casey Schaufler 已提交
656
	rc = smk_bu_current("statfs", sbp->smk_floor, MAY_READ, rc);
E
Etienne Basset 已提交
657
	return rc;
658 659
}

660 661 662 663
/*
 * BPRM hooks
 */

C
Casey Schaufler 已提交
664 665 666 667
/**
 * smack_bprm_set_creds - set creds for exec
 * @bprm: the exec information
 *
668
 * Returns 0 if it gets a blob, -EPERM if exec forbidden and -ENOMEM otherwise
C
Casey Schaufler 已提交
669
 */
670 671
static int smack_bprm_set_creds(struct linux_binprm *bprm)
{
A
Al Viro 已提交
672
	struct inode *inode = file_inode(bprm->file);
673
	struct task_smack *bsp = bprm->cred->security;
674 675 676 677 678 679 680 681 682 683
	struct inode_smack *isp;
	int rc;

	rc = cap_bprm_set_creds(bprm);
	if (rc != 0)
		return rc;

	if (bprm->cred_prepared)
		return 0;

684 685
	isp = inode->i_security;
	if (isp->smk_task == NULL || isp->smk_task == bsp->smk_task)
686 687
		return 0;

688 689 690 691 692 693 694 695
	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,
696
						   isp->smk_task,
697 698 699 700 701 702 703
						   PTRACE_MODE_ATTACH,
						   __func__);
		rcu_read_unlock();

		if (rc != 0)
			return rc;
	} else if (bprm->unsafe)
704
		return -EPERM;
705

706 707
	bsp->smk_task = isp->smk_task;
	bprm->per_clear |= PER_CLEAR_ON_SETID;
708

709 710
	return 0;
}
711

712 713 714 715 716 717 718 719 720
/**
 * 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;
721

722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740
	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();
	int ret = cap_bprm_secureexec(bprm);

	if (!ret && (tsp->smk_task != tsp->smk_forked))
		ret = 1;

	return ret;
741 742
}

743 744 745 746 747 748
/*
 * Inode hooks
 */

/**
 * smack_inode_alloc_security - allocate an inode blob
749
 * @inode: the inode in need of a blob
750 751 752 753 754
 *
 * Returns 0 if it gets a blob, -ENOMEM otherwise
 */
static int smack_inode_alloc_security(struct inode *inode)
{
755 756
	struct smack_known *skp = smk_of_current();

757
	inode->i_security = new_inode_smack(skp);
758 759 760 761 762 763 764
	if (inode->i_security == NULL)
		return -ENOMEM;
	return 0;
}

/**
 * smack_inode_free_security - free an inode blob
765
 * @inode: the inode with a blob
766 767 768 769 770
 *
 * Clears the blob pointer in inode
 */
static void smack_inode_free_security(struct inode *inode)
{
771
	kmem_cache_free(smack_inode_cache, inode->i_security);
772 773 774 775 776
	inode->i_security = NULL;
}

/**
 * smack_inode_init_security - copy out the smack from an inode
777 778
 * @inode: the newly created inode
 * @dir: containing directory object
779
 * @qstr: unused
780 781 782 783 784 785 786
 * @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,
787
				     const struct qstr *qstr, const char **name,
788
				     void **value, size_t *len)
789
{
C
Casey Schaufler 已提交
790
	struct inode_smack *issp = inode->i_security;
791
	struct smack_known *skp = smk_of_current();
792 793
	struct smack_known *isp = smk_of_inode(inode);
	struct smack_known *dsp = smk_of_inode(dir);
794
	int may;
795

796 797
	if (name)
		*name = XATTR_SMACK_SUFFIX;
798 799

	if (value) {
800
		rcu_read_lock();
801 802
		may = smk_access_entry(skp->smk_known, dsp->smk_known,
				       &skp->smk_rules);
803
		rcu_read_unlock();
804 805 806 807 808

		/*
		 * If the access rule allows transmutation and
		 * the directory requests transmutation then
		 * by all means transmute.
C
Casey Schaufler 已提交
809
		 * Mark the inode as changed.
810
		 */
811
		if (may > 0 && ((may & MAY_TRANSMUTE) != 0) &&
C
Casey Schaufler 已提交
812
		    smk_inode_transmutable(dir)) {
813
			isp = dsp;
C
Casey Schaufler 已提交
814 815
			issp->smk_flags |= SMK_INODE_CHANGED;
		}
816

817
		*value = kstrdup(isp->smk_known, GFP_NOFS);
818 819 820 821 822
		if (*value == NULL)
			return -ENOMEM;
	}

	if (len)
823
		*len = strlen(isp->smk_known);
824 825 826 827 828 829 830 831 832 833 834 835 836 837 838

	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)
{
839
	struct smack_known *isp;
E
Etienne Basset 已提交
840 841 842
	struct smk_audit_info ad;
	int rc;

843
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
E
Etienne Basset 已提交
844
	smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
845 846

	isp = smk_of_inode(old_dentry->d_inode);
E
Etienne Basset 已提交
847
	rc = smk_curacc(isp, MAY_WRITE, &ad);
C
Casey Schaufler 已提交
848
	rc = smk_bu_inode(old_dentry->d_inode, MAY_WRITE, rc);
849 850 851

	if (rc == 0 && new_dentry->d_inode != NULL) {
		isp = smk_of_inode(new_dentry->d_inode);
E
Etienne Basset 已提交
852 853
		smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
		rc = smk_curacc(isp, MAY_WRITE, &ad);
C
Casey Schaufler 已提交
854
		rc = smk_bu_inode(new_dentry->d_inode, MAY_WRITE, rc);
855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870
	}

	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)
{
	struct inode *ip = dentry->d_inode;
E
Etienne Basset 已提交
871
	struct smk_audit_info ad;
872 873
	int rc;

874
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
E
Etienne Basset 已提交
875 876
	smk_ad_setfield_u_fs_path_dentry(&ad, dentry);

877 878 879
	/*
	 * You need write access to the thing you're unlinking
	 */
E
Etienne Basset 已提交
880
	rc = smk_curacc(smk_of_inode(ip), MAY_WRITE, &ad);
C
Casey Schaufler 已提交
881
	rc = smk_bu_inode(ip, MAY_WRITE, rc);
E
Etienne Basset 已提交
882
	if (rc == 0) {
883 884 885
		/*
		 * You also need write access to the containing directory
		 */
886
		smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
E
Etienne Basset 已提交
887 888
		smk_ad_setfield_u_fs_inode(&ad, dir);
		rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad);
C
Casey Schaufler 已提交
889
		rc = smk_bu_inode(dir, MAY_WRITE, rc);
E
Etienne Basset 已提交
890
	}
891 892 893 894 895 896 897 898 899 900 901 902 903
	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
904
	struct smk_audit_info ad;
905 906
	int rc;

907
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
E
Etienne Basset 已提交
908 909
	smk_ad_setfield_u_fs_path_dentry(&ad, dentry);

910 911 912
	/*
	 * You need write access to the thing you're removing
	 */
E
Etienne Basset 已提交
913
	rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
C
Casey Schaufler 已提交
914
	rc = smk_bu_inode(dentry->d_inode, MAY_WRITE, rc);
E
Etienne Basset 已提交
915
	if (rc == 0) {
916 917 918
		/*
		 * You also need write access to the containing directory
		 */
919
		smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
E
Etienne Basset 已提交
920 921
		smk_ad_setfield_u_fs_inode(&ad, dir);
		rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad);
C
Casey Schaufler 已提交
922
		rc = smk_bu_inode(dir, MAY_WRITE, rc);
E
Etienne Basset 已提交
923
	}
924 925 926 927 928 929

	return rc;
}

/**
 * smack_inode_rename - Smack check on rename
930 931 932 933
 * @old_inode: unused
 * @old_dentry: the old object
 * @new_inode: unused
 * @new_dentry: the new object
934 935 936 937 938 939 940 941 942 943 944 945
 *
 * 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;
946
	struct smack_known *isp;
E
Etienne Basset 已提交
947 948
	struct smk_audit_info ad;

949
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
E
Etienne Basset 已提交
950
	smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
951 952

	isp = smk_of_inode(old_dentry->d_inode);
E
Etienne Basset 已提交
953
	rc = smk_curacc(isp, MAY_READWRITE, &ad);
C
Casey Schaufler 已提交
954
	rc = smk_bu_inode(old_dentry->d_inode, MAY_READWRITE, rc);
955 956 957

	if (rc == 0 && new_dentry->d_inode != NULL) {
		isp = smk_of_inode(new_dentry->d_inode);
E
Etienne Basset 已提交
958 959
		smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
		rc = smk_curacc(isp, MAY_READWRITE, &ad);
C
Casey Schaufler 已提交
960
		rc = smk_bu_inode(new_dentry->d_inode, MAY_READWRITE, rc);
961 962 963 964 965 966 967 968 969 970 971 972 973
	}
	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
 */
974
static int smack_inode_permission(struct inode *inode, int mask)
975
{
E
Etienne Basset 已提交
976
	struct smk_audit_info ad;
977
	int no_block = mask & MAY_NOT_BLOCK;
C
Casey Schaufler 已提交
978
	int rc;
979 980

	mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
981 982 983 984 985
	/*
	 * No permission to check. Existence test. Yup, it's there.
	 */
	if (mask == 0)
		return 0;
986 987

	/* May be droppable after audit */
988
	if (no_block)
989
		return -ECHILD;
990
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
E
Etienne Basset 已提交
991
	smk_ad_setfield_u_fs_inode(&ad, inode);
C
Casey Schaufler 已提交
992 993 994
	rc = smk_curacc(smk_of_inode(inode), mask, &ad);
	rc = smk_bu_inode(inode, mask, rc);
	return rc;
995 996 997 998 999 1000 1001 1002 1003 1004 1005
}

/**
 * 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
1006
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
1007 1008
	int rc;

1009 1010 1011 1012 1013
	/*
	 * Need to allow for clearing the setuid bit.
	 */
	if (iattr->ia_valid & ATTR_FORCE)
		return 0;
1014
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
E
Etienne Basset 已提交
1015
	smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1016

C
Casey Schaufler 已提交
1017 1018 1019
	rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
	rc = smk_bu_inode(dentry->d_inode, MAY_WRITE, rc);
	return rc;
1020 1021 1022 1023
}

/**
 * smack_inode_getattr - Smack check for getting attributes
1024
 * @mnt: vfsmount of the object
1025 1026 1027 1028 1029 1030
 * @dentry: the object
 *
 * Returns 0 if access is permitted, an error code otherwise
 */
static int smack_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
{
E
Etienne Basset 已提交
1031
	struct smk_audit_info ad;
1032
	struct path path;
C
Casey Schaufler 已提交
1033
	int rc;
E
Etienne Basset 已提交
1034

1035 1036
	path.dentry = dentry;
	path.mnt = mnt;
E
Etienne Basset 已提交
1037

1038
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1039
	smk_ad_setfield_u_fs_path(&ad, path);
C
Casey Schaufler 已提交
1040 1041 1042
	rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ, &ad);
	rc = smk_bu_inode(dentry->d_inode, MAY_READ, rc);
	return rc;
1043 1044 1045 1046 1047 1048
}

/**
 * smack_inode_setxattr - Smack check for setting xattrs
 * @dentry: the object
 * @name: name of the attribute
1049 1050
 * @value: value of the attribute
 * @size: size of the value
1051 1052 1053 1054 1055 1056
 * @flags: unused
 *
 * This protects the Smack attribute explicitly.
 *
 * Returns 0 if access is permitted, an error code otherwise
 */
1057 1058
static int smack_inode_setxattr(struct dentry *dentry, const char *name,
				const void *value, size_t size, int flags)
1059
{
E
Etienne Basset 已提交
1060
	struct smk_audit_info ad;
1061 1062 1063 1064
	struct smack_known *skp;
	int check_priv = 0;
	int check_import = 0;
	int check_star = 0;
1065
	int rc = 0;
1066

1067 1068 1069
	/*
	 * Check label validity here so import won't fail in post_setxattr
	 */
1070 1071
	if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
	    strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
1072 1073 1074 1075 1076 1077 1078 1079
	    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;
1080
	} else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) {
1081
		check_priv = 1;
1082 1083 1084
		if (size != TRANS_TRUE_SIZE ||
		    strncmp(value, TRANS_TRUE, TRANS_TRUE_SIZE) != 0)
			rc = -EINVAL;
1085 1086 1087
	} else
		rc = cap_inode_setxattr(dentry, name, value, size, flags);

1088 1089 1090 1091
	if (check_priv && !smack_privileged(CAP_MAC_ADMIN))
		rc = -EPERM;

	if (rc == 0 && check_import) {
1092
		skp = size ? smk_import_entry(value, size) : NULL;
1093 1094 1095 1096 1097
		if (skp == NULL || (check_star &&
		    (skp == &smack_known_star || skp == &smack_known_web)))
			rc = -EINVAL;
	}

1098
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
E
Etienne Basset 已提交
1099 1100
	smk_ad_setfield_u_fs_path_dentry(&ad, dentry);

C
Casey Schaufler 已提交
1101
	if (rc == 0) {
E
Etienne Basset 已提交
1102
		rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
C
Casey Schaufler 已提交
1103 1104
		rc = smk_bu_inode(dentry->d_inode, MAY_WRITE, rc);
	}
1105 1106

	return rc;
1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119
}

/**
 * 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.
 */
1120 1121
static void smack_inode_post_setxattr(struct dentry *dentry, const char *name,
				      const void *value, size_t size, int flags)
1122
{
1123
	struct smack_known *skp;
1124
	struct inode_smack *isp = dentry->d_inode->i_security;
1125

1126 1127 1128 1129 1130
	if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) {
		isp->smk_flags |= SMK_INODE_TRANSMUTE;
		return;
	}

1131
	if (strcmp(name, XATTR_NAME_SMACK) == 0) {
1132
		skp = smk_import_entry(value, size);
1133
		if (skp != NULL)
1134
			isp->smk_inode = skp;
1135
		else
1136
			isp->smk_inode = &smack_known_invalid;
1137
	} else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0) {
1138
		skp = smk_import_entry(value, size);
1139 1140
		if (skp != NULL)
			isp->smk_task = skp;
1141
		else
1142
			isp->smk_task = &smack_known_invalid;
1143
	} else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
1144
		skp = smk_import_entry(value, size);
1145 1146
		if (skp != NULL)
			isp->smk_mmap = skp;
1147
		else
1148 1149
			isp->smk_mmap = &smack_known_invalid;
	}
1150 1151 1152 1153

	return;
}

C
Casey Schaufler 已提交
1154
/**
1155 1156 1157 1158 1159 1160
 * smack_inode_getxattr - Smack check on getxattr
 * @dentry: the object
 * @name: unused
 *
 * Returns 0 if access is permitted, an error code otherwise
 */
1161
static int smack_inode_getxattr(struct dentry *dentry, const char *name)
1162
{
E
Etienne Basset 已提交
1163
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
1164
	int rc;
E
Etienne Basset 已提交
1165

1166
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
E
Etienne Basset 已提交
1167 1168
	smk_ad_setfield_u_fs_path_dentry(&ad, dentry);

C
Casey Schaufler 已提交
1169 1170 1171
	rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ, &ad);
	rc = smk_bu_inode(dentry->d_inode, MAY_READ, rc);
	return rc;
1172 1173
}

C
Casey Schaufler 已提交
1174
/**
1175 1176 1177 1178 1179 1180 1181 1182
 * 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
 */
1183
static int smack_inode_removexattr(struct dentry *dentry, const char *name)
1184
{
1185
	struct inode_smack *isp;
E
Etienne Basset 已提交
1186
	struct smk_audit_info ad;
1187
	int rc = 0;
1188

1189 1190
	if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
	    strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
1191
	    strcmp(name, XATTR_NAME_SMACKIPOUT) == 0 ||
1192
	    strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
1193
	    strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0 ||
P
Pankaj Kumar 已提交
1194
	    strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
1195
		if (!smack_privileged(CAP_MAC_ADMIN))
1196 1197 1198 1199
			rc = -EPERM;
	} else
		rc = cap_inode_removexattr(dentry, name);

1200 1201 1202
	if (rc != 0)
		return rc;

1203
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
E
Etienne Basset 已提交
1204
	smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1205

1206
	rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
C
Casey Schaufler 已提交
1207
	rc = smk_bu_inode(dentry->d_inode, MAY_WRITE, rc);
1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218
	if (rc != 0)
		return rc;

	isp = dentry->d_inode->i_security;
	/*
	 * Don't do anything special for these.
	 *	XATTR_NAME_SMACKIPIN
	 *	XATTR_NAME_SMACKIPOUT
	 *	XATTR_NAME_SMACKEXEC
	 */
	if (strcmp(name, XATTR_NAME_SMACK) == 0)
1219
		isp->smk_task = NULL;
1220
	else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0)
1221
		isp->smk_mmap = NULL;
1222 1223
	else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0)
		isp->smk_flags &= ~SMK_INODE_TRANSMUTE;
1224

1225
	return 0;
1226 1227 1228 1229 1230 1231 1232
}

/**
 * smack_inode_getsecurity - get smack xattrs
 * @inode: the object
 * @name: attribute name
 * @buffer: where to put the result
1233
 * @alloc: unused
1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244
 *
 * Returns the size of the attribute or an error code
 */
static int smack_inode_getsecurity(const struct inode *inode,
				   const char *name, void **buffer,
				   bool alloc)
{
	struct socket_smack *ssp;
	struct socket *sock;
	struct super_block *sbp;
	struct inode *ip = (struct inode *)inode;
1245
	struct smack_known *isp;
1246 1247 1248 1249 1250
	int ilen;
	int rc = 0;

	if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
		isp = smk_of_inode(inode);
1251 1252
		ilen = strlen(isp->smk_known);
		*buffer = isp->smk_known;
1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263
		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);
1264
	if (sock == NULL || sock->sk == NULL)
1265 1266 1267 1268 1269
		return -EOPNOTSUPP;

	ssp = sock->sk->sk_security;

	if (strcmp(name, XATTR_SMACK_IPIN) == 0)
1270
		isp = ssp->smk_in;
1271
	else if (strcmp(name, XATTR_SMACK_IPOUT) == 0)
1272
		isp = ssp->smk_out;
1273 1274 1275
	else
		return -EOPNOTSUPP;

1276
	ilen = strlen(isp->smk_known);
1277
	if (rc == 0) {
1278
		*buffer = isp->smk_known;
1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296
		rc = ilen;
	}

	return rc;
}


/**
 * smack_inode_listsecurity - list the Smack attributes
 * @inode: the object
 * @buffer: where they go
 * @buffer_size: size of buffer
 *
 * Returns 0 on success, -EINVAL otherwise
 */
static int smack_inode_listsecurity(struct inode *inode, char *buffer,
				    size_t buffer_size)
{
1297
	int len = sizeof(XATTR_NAME_SMACK);
1298

1299
	if (buffer != NULL && len <= buffer_size)
1300
		memcpy(buffer, XATTR_NAME_SMACK, len);
1301 1302

	return len;
1303 1304
}

1305 1306 1307 1308 1309 1310 1311 1312 1313
/**
 * smack_inode_getsecid - Extract inode's security id
 * @inode: inode to extract the info from
 * @secid: where result will be saved
 */
static void smack_inode_getsecid(const struct inode *inode, u32 *secid)
{
	struct inode_smack *isp = inode->i_security;

1314
	*secid = isp->smk_inode->smk_secid;
1315 1316
}

1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350
/*
 * File Hooks
 */

/**
 * smack_file_permission - Smack check on file operations
 * @file: unused
 * @mask: unused
 *
 * Returns 0
 *
 * 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.
 */
static int smack_file_permission(struct file *file, int mask)
{
	return 0;
}

/**
 * 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.
 *
 * Returns 0
 */
static int smack_file_alloc_security(struct file *file)
{
1351 1352
	struct smack_known *skp = smk_of_current();

1353
	file->f_security = skp;
1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382
	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
1383 1384
	struct smk_audit_info ad;

1385
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
E
Etienne Basset 已提交
1386
	smk_ad_setfield_u_fs_path(&ad, file->f_path);
1387

C
Casey Schaufler 已提交
1388
	if (_IOC_DIR(cmd) & _IOC_WRITE) {
E
Etienne Basset 已提交
1389
		rc = smk_curacc(file->f_security, MAY_WRITE, &ad);
C
Casey Schaufler 已提交
1390 1391
		rc = smk_bu_file(file, MAY_WRITE, rc);
	}
1392

C
Casey Schaufler 已提交
1393
	if (rc == 0 && (_IOC_DIR(cmd) & _IOC_READ)) {
E
Etienne Basset 已提交
1394
		rc = smk_curacc(file->f_security, MAY_READ, &ad);
C
Casey Schaufler 已提交
1395 1396
		rc = smk_bu_file(file, MAY_READ, rc);
	}
1397 1398 1399 1400 1401 1402 1403

	return rc;
}

/**
 * smack_file_lock - Smack check on file locking
 * @file: the object
1404
 * @cmd: unused
1405
 *
1406
 * Returns 0 if current has lock access, error code otherwise
1407 1408 1409
 */
static int smack_file_lock(struct file *file, unsigned int cmd)
{
E
Etienne Basset 已提交
1410
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
1411
	int rc;
E
Etienne Basset 已提交
1412

1413 1414
	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
1415 1416 1417
	rc = smk_curacc(file->f_security, MAY_LOCK, &ad);
	rc = smk_bu_file(file, MAY_LOCK, rc);
	return rc;
1418 1419 1420 1421 1422 1423 1424 1425
}

/**
 * smack_file_fcntl - Smack check on fcntl
 * @file: the object
 * @cmd: what action to check
 * @arg: unused
 *
1426 1427 1428 1429
 * Generally these operations are harmless.
 * File locking operations present an obvious mechanism
 * for passing information, so they require write access.
 *
1430 1431 1432 1433 1434
 * 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
1435
	struct smk_audit_info ad;
1436
	int rc = 0;
1437

E
Etienne Basset 已提交
1438

1439 1440
	switch (cmd) {
	case F_GETLK:
1441
		break;
1442 1443
	case F_SETLK:
	case F_SETLKW:
1444 1445 1446
		smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
		smk_ad_setfield_u_fs_path(&ad, file->f_path);
		rc = smk_curacc(file->f_security, MAY_LOCK, &ad);
C
Casey Schaufler 已提交
1447
		rc = smk_bu_file(file, MAY_LOCK, rc);
1448
		break;
1449 1450
	case F_SETOWN:
	case F_SETSIG:
1451 1452
		smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
		smk_ad_setfield_u_fs_path(&ad, file->f_path);
E
Etienne Basset 已提交
1453
		rc = smk_curacc(file->f_security, MAY_WRITE, &ad);
C
Casey Schaufler 已提交
1454
		rc = smk_bu_file(file, MAY_WRITE, rc);
1455 1456
		break;
	default:
1457
		break;
1458 1459 1460 1461 1462
	}

	return rc;
}

1463
/**
1464
 * smack_mmap_file :
1465 1466 1467 1468 1469 1470 1471 1472
 * 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.
 */
1473
static int smack_mmap_file(struct file *file,
1474
			   unsigned long reqprot, unsigned long prot,
1475
			   unsigned long flags)
1476
{
1477
	struct smack_known *skp;
1478
	struct smack_known *mkp;
1479 1480
	struct smack_rule *srp;
	struct task_smack *tsp;
1481
	struct smack_known *okp;
1482
	struct inode_smack *isp;
1483 1484 1485
	int may;
	int mmay;
	int tmay;
1486 1487
	int rc;

A
Al Viro 已提交
1488
	if (file == NULL)
1489 1490
		return 0;

A
Al Viro 已提交
1491
	isp = file_inode(file)->i_security;
1492 1493
	if (isp->smk_mmap == NULL)
		return 0;
1494
	mkp = isp->smk_mmap;
1495 1496

	tsp = current_security();
1497
	skp = smk_of_current();
1498 1499 1500 1501 1502 1503 1504 1505
	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.
	 */
1506
	list_for_each_entry_rcu(srp, &skp->smk_rules, list) {
1507
		okp = srp->smk_object;
1508 1509 1510
		/*
		 * Matching labels always allows access.
		 */
1511
		if (mkp->smk_known == okp->smk_known)
1512
			continue;
1513 1514 1515 1516
		/*
		 * If there is a matching local rule take
		 * that into account as well.
		 */
1517 1518 1519
		may = smk_access_entry(srp->smk_subject->smk_known,
				       okp->smk_known,
				       &tsp->smk_rules);
1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535
		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.
		 */
1536 1537
		mmay = smk_access_entry(mkp->smk_known, okp->smk_known,
					&mkp->smk_rules);
1538 1539 1540 1541 1542 1543 1544 1545
		if (mmay == -ENOENT) {
			rc = -EACCES;
			break;
		}
		/*
		 * If there is a local entry it modifies the
		 * potential access, too.
		 */
1546 1547
		tmay = smk_access_entry(mkp->smk_known, okp->smk_known,
					&tsp->smk_rules);
1548 1549
		if (tmay != -ENOENT)
			mmay &= tmay;
1550

1551 1552 1553 1554 1555
		/*
		 * If there is any access available to current that is
		 * not available to a SMACK64MMAP subject
		 * deny access.
		 */
1556
		if ((may | mmay) != mmay) {
1557
			rc = -EACCES;
1558
			break;
1559
		}
1560 1561 1562 1563 1564 1565 1566
	}

	rcu_read_unlock();

	return rc;
}

1567 1568 1569 1570 1571 1572 1573
/**
 * smack_file_set_fowner - set the file security blob value
 * @file: object in question
 *
 * Returns 0
 * Further research may be required on this one.
 */
1574
static void smack_file_set_fowner(struct file *file)
1575
{
1576 1577
	struct smack_known *skp = smk_of_current();

1578
	file->f_security = skp;
1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594
}

/**
 * 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)
{
1595 1596
	struct smack_known *skp;
	struct smack_known *tkp = smk_of_task(tsk->cred->security);
1597 1598
	struct file *file;
	int rc;
E
Etienne Basset 已提交
1599
	struct smk_audit_info ad;
1600 1601 1602 1603 1604

	/*
	 * struct fown_struct is never outside the context of a struct file
	 */
	file = container_of(fown, struct file, f_owner);
1605

E
Etienne Basset 已提交
1606
	/* we don't log here as rc can be overriden */
1607 1608 1609
	skp = file->f_security;
	rc = smk_access(skp, tkp, MAY_WRITE, NULL);
	rc = smk_bu_note("sigiotask", skp, tkp, MAY_WRITE, rc);
1610
	if (rc != 0 && has_capability(tsk, CAP_MAC_OVERRIDE))
E
Etienne Basset 已提交
1611 1612 1613 1614
		rc = 0;

	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
	smk_ad_setfield_u_tsk(&ad, tsk);
1615
	smack_log(skp->smk_known, tkp->smk_known, MAY_WRITE, rc, &ad);
1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626
	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
1627
	int rc;
1628
	int may = 0;
E
Etienne Basset 已提交
1629
	struct smk_audit_info ad;
1630

1631
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
E
Etienne Basset 已提交
1632
	smk_ad_setfield_u_fs_path(&ad, file->f_path);
1633 1634 1635 1636 1637 1638 1639 1640
	/*
	 * 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
1641 1642 1643
	rc = smk_curacc(file->f_security, may, &ad);
	rc = smk_bu_file(file, may, rc);
	return rc;
1644 1645
}

1646
/**
1647
 * smack_file_open - Smack dentry open processing
1648
 * @file: the object
1649
 * @cred: task credential
1650 1651
 *
 * Set the security blob in the file structure.
1652 1653 1654
 * 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.
1655 1656 1657
 *
 * Returns 0
 */
1658
static int smack_file_open(struct file *file, const struct cred *cred)
1659
{
1660
	struct task_smack *tsp = cred->security;
A
Al Viro 已提交
1661
	struct inode_smack *isp = file_inode(file)->i_security;
1662 1663
	struct smk_audit_info ad;
	int rc;
1664

1665 1666
	if (smack_privileged(CAP_MAC_OVERRIDE)) {
		file->f_security = isp->smk_inode;
1667
		return 0;
1668
	}
1669

1670 1671 1672
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
	smk_ad_setfield_u_fs_path(&ad, file->f_path);
	rc = smk_access(tsp->smk_task, isp->smk_inode, MAY_READ, &ad);
C
Casey Schaufler 已提交
1673
	rc = smk_bu_credfile(cred, file, MAY_READ, rc);
1674 1675 1676 1677
	if (rc == 0)
		file->f_security = isp->smk_inode;

	return rc;
1678 1679
}

1680 1681 1682 1683
/*
 * Task hooks
 */

1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694
/**
 * 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)
{
1695 1696 1697 1698
	struct task_smack *tsp;

	tsp = new_task_smack(NULL, NULL, gfp);
	if (tsp == NULL)
1699
		return -ENOMEM;
1700 1701 1702

	cred->security = tsp;

1703 1704 1705 1706
	return 0;
}


1707
/**
1708 1709
 * smack_cred_free - "free" task-level security credentials
 * @cred: the credentials in question
1710 1711
 *
 */
1712
static void smack_cred_free(struct cred *cred)
1713
{
1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728
	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;

	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);
1729 1730
}

D
David Howells 已提交
1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741
/**
 * 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)
{
1742 1743
	struct task_smack *old_tsp = old->security;
	struct task_smack *new_tsp;
1744
	int rc;
1745

1746
	new_tsp = new_task_smack(old_tsp->smk_task, old_tsp->smk_task, gfp);
1747 1748 1749
	if (new_tsp == NULL)
		return -ENOMEM;

1750 1751 1752 1753
	rc = smk_copy_rules(&new_tsp->smk_rules, &old_tsp->smk_rules, gfp);
	if (rc != 0)
		return rc;

1754
	new->security = new_tsp;
D
David Howells 已提交
1755 1756 1757
	return 0;
}

1758 1759 1760 1761 1762 1763 1764 1765 1766
/**
 * 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)
{
1767 1768 1769 1770 1771
	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;
1772 1773 1774 1775 1776
	mutex_init(&new_tsp->smk_rules_lock);
	INIT_LIST_HEAD(&new_tsp->smk_rules);


	/* cbs copy rule list */
1777 1778
}

1779 1780
/**
 * smack_kernel_act_as - Set the subjective context in a set of credentials
1781 1782
 * @new: points to the set of credentials to be modified.
 * @secid: specifies the security ID to be set
1783 1784 1785 1786 1787
 *
 * Set the security data for a kernel service.
 */
static int smack_kernel_act_as(struct cred *new, u32 secid)
{
1788
	struct task_smack *new_tsp = new->security;
1789
	struct smack_known *skp = smack_from_secid(secid);
1790

1791
	if (skp == NULL)
1792 1793
		return -EINVAL;

1794
	new_tsp->smk_task = skp;
1795 1796 1797 1798 1799
	return 0;
}

/**
 * smack_kernel_create_files_as - Set the file creation label in a set of creds
1800 1801
 * @new: points to the set of credentials to be modified
 * @inode: points to the inode to use as a reference
1802 1803 1804 1805 1806 1807 1808 1809
 *
 * 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;
1810
	struct task_smack *tsp = new->security;
1811

1812
	tsp->smk_forked = isp->smk_inode;
1813
	tsp->smk_task = tsp->smk_forked;
1814 1815 1816
	return 0;
}

E
Etienne Basset 已提交
1817 1818 1819
/**
 * smk_curacc_on_task - helper to log task related access
 * @p: the task object
1820 1821
 * @access: the access requested
 * @caller: name of the calling function for audit
E
Etienne Basset 已提交
1822 1823 1824
 *
 * Return 0 if access is permitted
 */
1825 1826
static int smk_curacc_on_task(struct task_struct *p, int access,
				const char *caller)
E
Etienne Basset 已提交
1827 1828
{
	struct smk_audit_info ad;
1829
	struct smack_known *skp = smk_of_task(task_security(p));
C
Casey Schaufler 已提交
1830
	int rc;
E
Etienne Basset 已提交
1831

1832
	smk_ad_init(&ad, caller, LSM_AUDIT_DATA_TASK);
E
Etienne Basset 已提交
1833
	smk_ad_setfield_u_tsk(&ad, p);
1834
	rc = smk_curacc(skp, access, &ad);
C
Casey Schaufler 已提交
1835 1836
	rc = smk_bu_task(p, access, rc);
	return rc;
E
Etienne Basset 已提交
1837 1838
}

1839 1840 1841 1842 1843 1844 1845 1846 1847
/**
 * 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)
{
1848
	return smk_curacc_on_task(p, MAY_WRITE, __func__);
1849 1850 1851 1852 1853 1854 1855 1856 1857 1858
}

/**
 * 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)
{
1859
	return smk_curacc_on_task(p, MAY_READ, __func__);
1860 1861 1862 1863 1864 1865 1866 1867 1868 1869
}

/**
 * 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)
{
1870
	return smk_curacc_on_task(p, MAY_READ, __func__);
1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881
}

/**
 * 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)
{
1882 1883 1884
	struct smack_known *skp = smk_of_task(task_security(p));

	*secid = skp->smk_secid;
1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895
}

/**
 * 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)
{
1896 1897 1898 1899
	int rc;

	rc = cap_task_setnice(p, nice);
	if (rc == 0)
1900
		rc = smk_curacc_on_task(p, MAY_WRITE, __func__);
1901
	return rc;
1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912
}

/**
 * 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)
{
1913 1914 1915 1916
	int rc;

	rc = cap_task_setioprio(p, ioprio);
	if (rc == 0)
1917
		rc = smk_curacc_on_task(p, MAY_WRITE, __func__);
1918
	return rc;
1919 1920 1921 1922 1923 1924 1925 1926 1927 1928
}

/**
 * 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)
{
1929
	return smk_curacc_on_task(p, MAY_READ, __func__);
1930 1931 1932 1933 1934 1935 1936 1937 1938 1939
}

/**
 * smack_task_setscheduler - Smack check on setting scheduler
 * @p: the task object
 * @policy: unused
 * @lp: unused
 *
 * Return 0 if read access is permitted
 */
1940
static int smack_task_setscheduler(struct task_struct *p)
1941
{
1942 1943
	int rc;

1944
	rc = cap_task_setscheduler(p);
1945
	if (rc == 0)
1946
		rc = smk_curacc_on_task(p, MAY_WRITE, __func__);
1947
	return rc;
1948 1949 1950 1951 1952 1953 1954 1955 1956 1957
}

/**
 * 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)
{
1958
	return smk_curacc_on_task(p, MAY_READ, __func__);
1959 1960 1961 1962 1963 1964 1965 1966 1967 1968
}

/**
 * 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)
{
1969
	return smk_curacc_on_task(p, MAY_WRITE, __func__);
1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986
}

/**
 * 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
1987
	struct smk_audit_info ad;
1988 1989
	struct smack_known *skp;
	struct smack_known *tkp = smk_of_task(task_security(p));
C
Casey Schaufler 已提交
1990
	int rc;
E
Etienne Basset 已提交
1991 1992 1993

	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
	smk_ad_setfield_u_tsk(&ad, p);
1994 1995 1996 1997
	/*
	 * Sending a signal requires that the sender
	 * can write the receiver.
	 */
C
Casey Schaufler 已提交
1998
	if (secid == 0) {
1999
		rc = smk_curacc(tkp, MAY_WRITE, &ad);
C
Casey Schaufler 已提交
2000 2001 2002
		rc = smk_bu_task(p, MAY_WRITE, rc);
		return rc;
	}
2003 2004 2005 2006 2007
	/*
	 * 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.
	 */
2008
	skp = smack_from_secid(secid);
2009 2010
	rc = smk_access(skp, tkp, MAY_WRITE, &ad);
	rc = smk_bu_note("USB signal", skp, tkp, MAY_WRITE, rc);
C
Casey Schaufler 已提交
2011
	return rc;
2012 2013 2014 2015 2016 2017
}

/**
 * smack_task_wait - Smack access check for waiting
 * @p: task to wait for
 *
2018
 * Returns 0
2019 2020 2021 2022
 */
static int smack_task_wait(struct task_struct *p)
{
	/*
2023 2024 2025 2026 2027 2028
	 * 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.
2029
	 */
2030
	return 0;
2031 2032 2033 2034 2035
}

/**
 * smack_task_to_inode - copy task smack into the inode blob
 * @p: task to copy from
2036
 * @inode: inode to copy to
2037 2038 2039 2040 2041 2042
 *
 * 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;
2043 2044
	struct smack_known *skp = smk_of_task(task_security(p));

2045
	isp->smk_inode = skp;
2046 2047 2048 2049 2050 2051 2052 2053 2054 2055
}

/*
 * Socket hooks.
 */

/**
 * smack_sk_alloc_security - Allocate a socket blob
 * @sk: the socket
 * @family: unused
2056
 * @gfp_flags: memory allocation flags
2057 2058 2059 2060 2061 2062 2063
 *
 * 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)
{
2064
	struct smack_known *skp = smk_of_current();
2065 2066 2067 2068 2069 2070
	struct socket_smack *ssp;

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

2071
	ssp->smk_in = skp;
2072
	ssp->smk_out = skp;
2073
	ssp->smk_packet = NULL;
2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090

	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)
{
	kfree(sk->sk_security);
}

2091 2092 2093 2094 2095 2096 2097 2098 2099 2100 2101 2102
/**
* smack_host_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.
*/
2103
static struct smack_known *smack_host_label(struct sockaddr_in *sip)
2104 2105 2106 2107 2108 2109 2110 2111 2112 2113 2114 2115 2116 2117
{
	struct smk_netlbladdr *snp;
	struct in_addr *siap = &sip->sin_addr;

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

	list_for_each_entry_rcu(snp, &smk_netlbladdr_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.sin_addr)->s_addr ==
2118 2119
		    (siap->s_addr & (&snp->smk_mask)->s_addr)) {
			/* we have found the special CIPSO option */
2120
			if (snp->smk_label == &smack_cipso_option)
2121
				return NULL;
2122
			return snp->smk_label;
2123
		}
2124 2125 2126 2127

	return NULL;
}

2128 2129 2130
/**
 * smack_netlabel - Set the secattr on a socket
 * @sk: the socket
2131
 * @labeled: socket label scheme
2132 2133 2134 2135 2136 2137
 *
 * Convert the outbound smack value (smk_out) to a
 * secattr and attach it to the socket.
 *
 * Returns 0 on success or an error code
 */
2138
static int smack_netlabel(struct sock *sk, int labeled)
2139
{
2140
	struct smack_known *skp;
2141
	struct socket_smack *ssp = sk->sk_security;
2142
	int rc = 0;
2143

2144 2145 2146 2147 2148 2149 2150 2151 2152 2153 2154 2155 2156 2157 2158
	/*
	 * 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 {
2159
		skp = ssp->smk_out;
2160
		rc = netlbl_sock_setattr(sk, sk->sk_family, &skp->smk_netlabel);
2161 2162 2163 2164
	}

	bh_unlock_sock(sk);
	local_bh_enable();
2165

2166 2167 2168
	return rc;
}

2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181
/**
 * 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)
{
2182
	struct smack_known *skp;
2183 2184
	int rc;
	int sk_lbl;
2185
	struct smack_known *hkp;
2186
	struct socket_smack *ssp = sk->sk_security;
E
Etienne Basset 已提交
2187
	struct smk_audit_info ad;
2188 2189

	rcu_read_lock();
2190 2191
	hkp = smack_host_label(sap);
	if (hkp != NULL) {
E
Etienne Basset 已提交
2192
#ifdef CONFIG_AUDIT
2193 2194
		struct lsm_network_audit net;

2195 2196 2197 2198
		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
2199
#endif
2200
		sk_lbl = SMACK_UNLABELED_SOCKET;
2201
		skp = ssp->smk_out;
2202 2203
		rc = smk_access(skp, hkp, MAY_WRITE, &ad);
		rc = smk_bu_note("IPv4 host check", skp, hkp, MAY_WRITE, rc);
2204 2205 2206 2207 2208 2209 2210 2211 2212 2213 2214
	} else {
		sk_lbl = SMACK_CIPSO_SOCKET;
		rc = 0;
	}
	rcu_read_unlock();
	if (rc != 0)
		return rc;

	return smack_netlabel(sk, sk_lbl);
}

2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 2236 2237 2238 2239 2240 2241 2242 2243 2244 2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262 2263 2264 2265 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294
/**
 * 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.
		 */
		list_for_each_entry(spp, &smk_ipv6_port_list, list) {
			if (sk != spp->smk_sock)
				continue;
			spp->smk_in = ssp->smk_in;
			spp->smk_out = ssp->smk_out;
			return;
		}
		/*
		 * A NULL address is only used for updating existing
		 * bound entries. If there isn't one, it's OK.
		 */
		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.
	 */
	list_for_each_entry(spp, &smk_ipv6_port_list, list) {
		if (spp->smk_port != port)
			continue;
		spp->smk_port = port;
		spp->smk_sock = sk;
		spp->smk_in = ssp->smk_in;
		spp->smk_out = ssp->smk_out;
		return;
	}

	/*
	 * 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;

	list_add(&spp->list, &smk_ipv6_port_list);
	return;
}

/**
 * smk_ipv6_port_check - check Smack port access
 * @sock: socket
 * @address: address
 *
 * Create or update the port list entry
 */
2295
static int smk_ipv6_port_check(struct sock *sk, struct sockaddr_in6 *address,
2296 2297 2298 2299 2300 2301
				int act)
{
	__be16 *bep;
	__be32 *be32p;
	struct smk_port_label *spp;
	struct socket_smack *ssp = sk->sk_security;
2302
	struct smack_known *skp;
2303
	unsigned short port = 0;
2304
	struct smack_known *object;
2305
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
2306
	int rc;
2307 2308 2309 2310 2311
#ifdef CONFIG_AUDIT
	struct lsm_network_audit net;
#endif

	if (act == SMK_RECEIVING) {
2312
		skp = smack_net_ambient;
2313
		object = ssp->smk_in;
2314
	} else {
2315
		skp = ssp->smk_out;
2316
		object = smack_net_ambient;
2317 2318 2319 2320 2321
	}

	/*
	 * Get the IP address and port from the address.
	 */
2322 2323 2324
	port = ntohs(address->sin6_port);
	bep = (__be16 *)(&address->sin6_addr);
	be32p = (__be32 *)(&address->sin6_addr);
2325 2326 2327 2328 2329 2330 2331 2332 2333 2334 2335

	/*
	 * It's remote, so port lookup does no good.
	 */
	if (be32p[0] || be32p[1] || be32p[2] || bep[6] || ntohs(bep[7]) != 1)
		goto auditout;

	/*
	 * It's local so the send check has to have passed.
	 */
	if (act == SMK_RECEIVING) {
2336
		skp = &smack_known_web;
2337 2338 2339 2340 2341 2342
		goto auditout;
	}

	list_for_each_entry(spp, &smk_ipv6_port_list, list) {
		if (spp->smk_port != port)
			continue;
2343
		object = spp->smk_in;
2344
		if (act == SMK_CONNECTING)
2345
			ssp->smk_packet = spp->smk_out;
2346 2347 2348 2349 2350 2351 2352 2353 2354 2355
		break;
	}

auditout:

#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->dport = port;
	if (act == SMK_RECEIVING)
2356
		ad.a.u.net->v6info.saddr = address->sin6_addr;
2357
	else
2358
		ad.a.u.net->v6info.daddr = address->sin6_addr;
2359
#endif
C
Casey Schaufler 已提交
2360 2361 2362
	rc = smk_access(skp, object, MAY_WRITE, &ad);
	rc = smk_bu_note("IPv6 port check", skp, object, MAY_WRITE, rc);
	return rc;
2363 2364
}

2365 2366 2367 2368 2369 2370 2371 2372 2373 2374 2375 2376 2377 2378 2379
/**
 * 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)
{
2380
	struct smack_known *skp;
2381 2382 2383
	struct inode_smack *nsp = inode->i_security;
	struct socket_smack *ssp;
	struct socket *sock;
2384
	int rc = 0;
2385

2386
	if (value == NULL || size > SMK_LONGLABEL || size == 0)
P
Pankaj Kumar 已提交
2387
		return -EINVAL;
2388

2389 2390
	skp = smk_import_entry(value, size);
	if (skp == NULL)
2391 2392 2393
		return -EINVAL;

	if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
2394
		nsp->smk_inode = skp;
2395
		nsp->smk_flags |= SMK_INODE_INSTANT;
2396 2397 2398 2399 2400 2401 2402 2403 2404
		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);
2405
	if (sock == NULL || sock->sk == NULL)
2406 2407 2408 2409 2410
		return -EOPNOTSUPP;

	ssp = sock->sk->sk_security;

	if (strcmp(name, XATTR_SMACK_IPIN) == 0)
2411
		ssp->smk_in = skp;
2412
	else if (strcmp(name, XATTR_SMACK_IPOUT) == 0) {
2413
		ssp->smk_out = skp;
2414
		if (sock->sk->sk_family == PF_INET) {
C
Casey Schaufler 已提交
2415 2416 2417 2418 2419 2420
			rc = smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET);
			if (rc != 0)
				printk(KERN_WARNING
					"Smack: \"%s\" netlbl error %d.\n",
					__func__, -rc);
		}
2421 2422 2423
	} else
		return -EOPNOTSUPP;

2424 2425 2426
	if (sock->sk->sk_family == PF_INET6)
		smk_ipv6_port_label(sock, NULL);

2427 2428 2429 2430 2431 2432 2433 2434 2435 2436 2437 2438 2439 2440 2441 2442 2443 2444
	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)
{
2445
	if (family != PF_INET || sock->sk == NULL)
2446 2447 2448 2449
		return 0;
	/*
	 * Set the outbound netlbl.
	 */
2450 2451 2452
	return smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET);
}

2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 2467 2468 2469 2470 2471
/**
 * 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;
}

2472 2473 2474 2475 2476 2477 2478 2479 2480 2481 2482 2483 2484
/**
 * 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)
{
2485 2486 2487
	int rc = 0;

	if (sock->sk == NULL)
2488 2489
		return 0;

2490 2491 2492 2493 2494 2495 2496 2497 2498
	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;
2499 2500
		rc = smk_ipv6_port_check(sock->sk, (struct sockaddr_in6 *)sap,
						SMK_CONNECTING);
2501 2502 2503
		break;
	}
	return rc;
2504 2505 2506 2507 2508 2509 2510 2511 2512 2513 2514 2515 2516 2517 2518 2519 2520 2521 2522 2523 2524 2525 2526 2527 2528 2529 2530 2531 2532 2533
}

/**
 * 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)
{
2534 2535
	struct smack_known *skp = smk_of_current();

2536
	msg->security = skp;
2537 2538 2539 2540 2541 2542 2543 2544 2545 2546 2547 2548 2549 2550 2551 2552 2553 2554 2555 2556
	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
 */
2557
static struct smack_known *smack_of_shm(struct shmid_kernel *shp)
2558
{
2559
	return (struct smack_known *)shp->shm_perm.security;
2560 2561 2562 2563 2564 2565 2566 2567 2568 2569 2570
}

/**
 * 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;
2571
	struct smack_known *skp = smk_of_current();
2572

2573
	isp->security = skp;
2574 2575 2576 2577 2578 2579 2580 2581 2582 2583 2584 2585 2586 2587 2588 2589
	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
2590 2591 2592 2593 2594 2595 2596 2597 2598
/**
 * 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)
{
2599
	struct smack_known *ssp = smack_of_shm(shp);
E
Etienne Basset 已提交
2600
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
2601
	int rc;
E
Etienne Basset 已提交
2602 2603 2604 2605 2606

#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
2607 2608 2609
	rc = smk_curacc(ssp, access, &ad);
	rc = smk_bu_current("shm", ssp, access, rc);
	return rc;
E
Etienne Basset 已提交
2610 2611
}

2612 2613 2614 2615 2616 2617 2618 2619 2620 2621 2622 2623
/**
 * 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
2624
	return smk_curacc_shm(shp, may);
2625 2626 2627 2628 2629 2630 2631 2632 2633 2634 2635 2636 2637 2638 2639 2640 2641 2642 2643 2644 2645 2646 2647 2648 2649 2650 2651 2652 2653 2654 2655 2656 2657
}

/**
 * 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
2658
	return smk_curacc_shm(shp, may);
2659 2660 2661 2662 2663 2664 2665 2666 2667 2668 2669 2670 2671 2672 2673 2674
}

/**
 * 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
2675
	return smk_curacc_shm(shp, may);
2676 2677 2678 2679 2680 2681 2682 2683
}

/**
 * smack_of_sem - the smack pointer for the sem
 * @sma: the object
 *
 * Returns a pointer to the smack value
 */
2684
static struct smack_known *smack_of_sem(struct sem_array *sma)
2685
{
2686
	return (struct smack_known *)sma->sem_perm.security;
2687 2688 2689 2690 2691 2692 2693 2694 2695 2696 2697
}

/**
 * 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;
2698
	struct smack_known *skp = smk_of_current();
2699

2700
	isp->security = skp;
2701 2702 2703 2704 2705 2706 2707 2708 2709 2710 2711 2712 2713 2714 2715 2716
	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
2717 2718 2719 2720 2721 2722 2723 2724 2725
/**
 * 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)
{
2726
	struct smack_known *ssp = smack_of_sem(sma);
E
Etienne Basset 已提交
2727
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
2728
	int rc;
E
Etienne Basset 已提交
2729 2730 2731 2732 2733

#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
2734 2735 2736
	rc = smk_curacc(ssp, access, &ad);
	rc = smk_bu_current("sem", ssp, access, rc);
	return rc;
E
Etienne Basset 已提交
2737 2738
}

2739 2740 2741 2742 2743 2744 2745 2746 2747 2748 2749 2750
/**
 * 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
2751
	return smk_curacc_sem(sma, may);
2752 2753 2754 2755 2756 2757 2758 2759 2760 2761 2762 2763 2764 2765 2766 2767 2768 2769 2770 2771 2772 2773 2774 2775 2776 2777 2778 2779 2780 2781 2782 2783 2784 2785 2786 2787 2788 2789 2790
}

/**
 * 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
2791
	return smk_curacc_sem(sma, may);
2792 2793 2794 2795 2796 2797 2798 2799 2800 2801 2802 2803 2804 2805 2806 2807
}

/**
 * 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
2808
	return smk_curacc_sem(sma, MAY_READWRITE);
2809 2810 2811 2812 2813 2814 2815 2816 2817 2818 2819
}

/**
 * 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;
2820
	struct smack_known *skp = smk_of_current();
2821

2822
	kisp->security = skp;
2823 2824 2825 2826 2827 2828 2829 2830 2831 2832 2833 2834 2835 2836 2837 2838 2839 2840 2841 2842
	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
 *
2843
 * Returns a pointer to the smack label entry
2844
 */
2845
static struct smack_known *smack_of_msq(struct msg_queue *msq)
2846
{
2847
	return (struct smack_known *)msq->q_perm.security;
2848 2849
}

E
Etienne Basset 已提交
2850 2851 2852 2853 2854 2855 2856 2857 2858
/**
 * 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)
{
2859
	struct smack_known *msp = smack_of_msq(msq);
E
Etienne Basset 已提交
2860
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
2861
	int rc;
E
Etienne Basset 已提交
2862 2863 2864 2865 2866

#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
2867 2868 2869
	rc = smk_curacc(msp, access, &ad);
	rc = smk_bu_current("msq", msp, access, rc);
	return rc;
E
Etienne Basset 已提交
2870 2871
}

2872 2873 2874 2875 2876 2877 2878 2879 2880 2881 2882 2883
/**
 * 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
2884
	return smk_curacc_msq(msq, may);
2885 2886 2887 2888 2889 2890 2891 2892 2893 2894 2895 2896 2897 2898 2899 2900 2901 2902 2903 2904 2905 2906 2907 2908 2909 2910 2911 2912 2913 2914 2915 2916
}

/**
 * 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
2917
	return smk_curacc_msq(msq, may);
2918 2919 2920 2921 2922 2923 2924 2925 2926 2927 2928 2929 2930
}

/**
 * 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
2931
	int may;
2932

E
Etienne Basset 已提交
2933 2934
	may = smack_flags_to_may(msqflg);
	return smk_curacc_msq(msq, may);
2935 2936 2937 2938 2939 2940 2941 2942 2943 2944 2945 2946 2947 2948 2949
}

/**
 * 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
2950
	return smk_curacc_msq(msq, MAY_READWRITE);
2951 2952 2953 2954 2955 2956 2957 2958 2959 2960 2961
}

/**
 * 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)
{
2962
	struct smack_known *iskp = ipp->security;
E
Etienne Basset 已提交
2963 2964
	int may = smack_flags_to_may(flag);
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
2965
	int rc;
2966

E
Etienne Basset 已提交
2967 2968 2969 2970
#ifdef CONFIG_AUDIT
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
	ad.a.u.ipc_id = ipp->id;
#endif
2971 2972
	rc = smk_curacc(iskp, may, &ad);
	rc = smk_bu_current("svipc", iskp, may, rc);
C
Casey Schaufler 已提交
2973
	return rc;
2974 2975
}

2976 2977
/**
 * smack_ipc_getsecid - Extract smack security id
2978
 * @ipp: the object permissions
2979 2980 2981 2982
 * @secid: where result will be saved
 */
static void smack_ipc_getsecid(struct kern_ipc_perm *ipp, u32 *secid)
{
2983
	struct smack_known *iskp = ipp->security;
2984

2985
	*secid = iskp->smk_secid;
2986 2987
}

2988 2989
/**
 * smack_d_instantiate - Make sure the blob is correct on an inode
2990
 * @opt_dentry: dentry where inode will be attached
2991 2992 2993 2994 2995 2996 2997 2998 2999
 * @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;
3000 3001
	struct smack_known *skp;
	struct smack_known *ckp = smk_of_current();
3002
	struct smack_known *final;
3003 3004
	char trattr[TRANS_TRUE_SIZE];
	int transflag = 0;
C
Casey Schaufler 已提交
3005
	int rc;
3006 3007 3008 3009 3010 3011 3012 3013 3014 3015 3016 3017 3018 3019 3020 3021 3022 3023 3024 3025 3026 3027 3028
	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
3029 3030 3031 3032 3033 3034 3035
	/*
	 * 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) {
3036 3037 3038 3039 3040 3041
		if (sbp->s_magic == CGROUP_SUPER_MAGIC) {
			/*
			 * The cgroup filesystem is never mounted,
			 * so there's no opportunity to set the mount
			 * options.
			 */
3042 3043
			sbsp->smk_root = &smack_known_star;
			sbsp->smk_default = &smack_known_star;
3044
		}
C
Casey Schaufler 已提交
3045 3046 3047 3048 3049
		isp->smk_inode = sbsp->smk_root;
		isp->smk_flags |= SMK_INODE_INSTANT;
		goto unlockandout;
	}

3050 3051 3052 3053 3054 3055 3056 3057
	/*
	 * 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:
3058 3059 3060
	case PIPEFS_MAGIC:
	case SOCKFS_MAGIC:
	case CGROUP_SUPER_MAGIC:
3061
		/*
L
Lucas De Marchi 已提交
3062
		 * Casey says that it's a little embarrassing
3063 3064
		 * that the smack file system doesn't do
		 * extended attributes.
3065
		 *
3066
		 * Casey says pipes are easy (?)
3067 3068 3069 3070 3071
		 *
		 * Socket access is controlled by the socket
		 * structures associated with the task involved.
		 *
		 * Cgroupfs is special
3072
		 */
3073
		final = &smack_known_star;
3074 3075 3076 3077 3078 3079 3080
		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.
		 */
3081
		final = ckp;
3082 3083 3084 3085 3086 3087 3088 3089 3090 3091 3092 3093 3094
		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.
		 */
3095
		final = &smack_known_star;
3096 3097 3098 3099 3100 3101 3102 3103 3104 3105 3106 3107
		/*
		 * 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
3108 3109 3110 3111 3112 3113
		 */

		/*
		 * UNIX domain sockets use lower level socket data.
		 */
		if (S_ISSOCK(inode->i_mode)) {
3114
			final = &smack_known_star;
C
Casey Schaufler 已提交
3115 3116 3117
			break;
		}
		/*
3118 3119 3120 3121 3122 3123 3124 3125 3126 3127
		 * 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.
		 */
		if (inode->i_op->getxattr == NULL)
			break;
		/*
		 * Get the dentry for xattr.
		 */
3128
		dp = dget(opt_dentry);
3129 3130
		skp = smk_fetch(XATTR_NAME_SMACK, inode, dp);
		if (skp != NULL)
3131
			final = skp;
C
Casey Schaufler 已提交
3132 3133 3134 3135 3136 3137 3138 3139 3140 3141 3142 3143 3144 3145 3146 3147 3148

		/*
		 * 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;
				rc = inode->i_op->setxattr(dp,
3149
					XATTR_NAME_SMACKTRANSMUTE,
C
Casey Schaufler 已提交
3150 3151 3152 3153 3154 3155 3156 3157 3158
					TRANS_TRUE, TRANS_TRUE_SIZE,
					0);
			} else {
				rc = inode->i_op->getxattr(dp,
					XATTR_NAME_SMACKTRANSMUTE, trattr,
					TRANS_TRUE_SIZE);
				if (rc >= 0 && strncmp(trattr, TRANS_TRUE,
						       TRANS_TRUE_SIZE) != 0)
					rc = -EINVAL;
3159
			}
C
Casey Schaufler 已提交
3160 3161
			if (rc >= 0)
				transflag = SMK_INODE_TRANSMUTE;
3162
		}
3163 3164 3165 3166 3167 3168 3169 3170 3171 3172 3173
		/*
		 * Don't let the exec or mmap label be "*" or "@".
		 */
		skp = smk_fetch(XATTR_NAME_SMACKEXEC, inode, dp);
		if (skp == &smack_known_star || skp == &smack_known_web)
			skp = NULL;
		isp->smk_task = skp;
		skp = smk_fetch(XATTR_NAME_SMACKMMAP, inode, dp);
		if (skp == &smack_known_star || skp == &smack_known_web)
			skp = NULL;
		isp->smk_mmap = skp;
3174

3175 3176 3177 3178 3179
		dput(dp);
		break;
	}

	if (final == NULL)
3180
		isp->smk_inode = ckp;
3181 3182 3183
	else
		isp->smk_inode = final;

3184
	isp->smk_flags |= (SMK_INODE_INSTANT | transflag);
3185 3186 3187 3188 3189 3190 3191 3192 3193 3194 3195 3196 3197 3198 3199 3200 3201 3202

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)
{
3203
	struct smack_known *skp = smk_of_task(task_security(p));
3204 3205 3206 3207 3208 3209
	char *cp;
	int slen;

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

3210
	cp = kstrdup(skp->smk_known, GFP_KERNEL);
3211 3212 3213 3214 3215 3216 3217 3218 3219 3220 3221 3222 3223 3224 3225 3226 3227 3228 3229 3230 3231 3232 3233
	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)
{
3234
	struct task_smack *tsp;
D
David Howells 已提交
3235
	struct cred *new;
3236
	struct smack_known *skp;
3237 3238 3239 3240 3241 3242 3243 3244

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

3245
	if (!smack_privileged(CAP_MAC_ADMIN))
3246 3247
		return -EPERM;

3248
	if (value == NULL || size == 0 || size >= SMK_LONGLABEL)
3249 3250 3251 3252 3253
		return -EINVAL;

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

3254 3255
	skp = smk_import_entry(value, size);
	if (skp == NULL)
3256 3257
		return -EINVAL;

3258 3259 3260
	/*
	 * No process is ever allowed the web ("@") label.
	 */
3261
	if (skp == &smack_known_web)
3262 3263
		return -EPERM;

D
David Howells 已提交
3264
	new = prepare_creds();
3265
	if (new == NULL)
D
David Howells 已提交
3266
		return -ENOMEM;
3267

3268
	tsp = new->security;
3269
	tsp->smk_task = skp;
3270

D
David Howells 已提交
3271
	commit_creds(new);
3272 3273 3274 3275 3276
	return size;
}

/**
 * smack_unix_stream_connect - Smack access on UDS
3277 3278
 * @sock: one sock
 * @other: the other sock
3279 3280 3281 3282 3283
 * @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
 */
3284 3285
static int smack_unix_stream_connect(struct sock *sock,
				     struct sock *other, struct sock *newsk)
3286
{
3287
	struct smack_known *skp;
3288
	struct smack_known *okp;
J
James Morris 已提交
3289 3290
	struct socket_smack *ssp = sock->sk_security;
	struct socket_smack *osp = other->sk_security;
3291
	struct socket_smack *nsp = newsk->sk_security;
E
Etienne Basset 已提交
3292
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
3293
	int rc = 0;
3294 3295 3296
#ifdef CONFIG_AUDIT
	struct lsm_network_audit net;
#endif
C
Casey Schaufler 已提交
3297

3298 3299
	if (!smack_privileged(CAP_MAC_OVERRIDE)) {
		skp = ssp->smk_out;
3300 3301 3302 3303 3304
		okp = osp->smk_out;
#ifdef CONFIG_AUDIT
		smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
		smk_ad_setfield_u_net_sk(&ad, other);
#endif
3305 3306
		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
3307
		if (rc == 0) {
3308 3309
			rc = smk_access(okp, skp, MAY_WRITE, NULL);
			rc = smk_bu_note("UDS connect", okp, skp,
C
Casey Schaufler 已提交
3310 3311
						MAY_WRITE, rc);
		}
3312
	}
C
Casey Schaufler 已提交
3313

3314 3315 3316 3317
	/*
	 * Cross reference the peer labels for SO_PEERSEC.
	 */
	if (rc == 0) {
3318 3319
		nsp->smk_packet = ssp->smk_out;
		ssp->smk_packet = osp->smk_out;
3320 3321
	}

C
Casey Schaufler 已提交
3322
	return rc;
3323 3324 3325 3326 3327 3328 3329 3330 3331 3332 3333 3334
}

/**
 * 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
3335 3336
	struct socket_smack *ssp = sock->sk->sk_security;
	struct socket_smack *osp = other->sk->sk_security;
E
Etienne Basset 已提交
3337
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
3338
	int rc;
3339

3340 3341 3342
#ifdef CONFIG_AUDIT
	struct lsm_network_audit net;

3343
	smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
E
Etienne Basset 已提交
3344
	smk_ad_setfield_u_net_sk(&ad, other->sk);
3345
#endif
C
Casey Schaufler 已提交
3346

3347 3348
	if (smack_privileged(CAP_MAC_OVERRIDE))
		return 0;
C
Casey Schaufler 已提交
3349

3350 3351
	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
3352
	return rc;
3353 3354
}

3355 3356 3357
/**
 * smack_socket_sendmsg - Smack check based on destination host
 * @sock: the socket
3358
 * @msg: the message
3359 3360
 * @size: the size of the message
 *
3361 3362 3363
 * 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.
3364 3365 3366 3367 3368
 */
static int smack_socket_sendmsg(struct socket *sock, struct msghdr *msg,
				int size)
{
	struct sockaddr_in *sip = (struct sockaddr_in *) msg->msg_name;
3369
	struct sockaddr_in6 *sap = (struct sockaddr_in6 *) msg->msg_name;
3370
	int rc = 0;
3371 3372 3373 3374

	/*
	 * Perfectly reasonable for this to be NULL
	 */
3375
	if (sip == NULL)
3376 3377
		return 0;

3378 3379 3380 3381 3382 3383 3384 3385 3386
	switch (sip->sin_family) {
	case AF_INET:
		rc = smack_netlabel_send(sock->sk, sip);
		break;
	case AF_INET6:
		rc = smk_ipv6_port_check(sock->sk, sap, SMK_SENDING);
		break;
	}
	return rc;
3387 3388
}

3389
/**
3390
 * smack_from_secattr - Convert a netlabel attr.mls.lvl/attr.mls.cat pair to smack
3391
 * @sap: netlabel secattr
3392
 * @ssp: socket security information
3393
 *
3394
 * Returns a pointer to a Smack label entry found on the label list.
3395
 */
3396 3397
static struct smack_known *smack_from_secattr(struct netlbl_lsm_secattr *sap,
						struct socket_smack *ssp)
3398
{
3399
	struct smack_known *skp;
3400
	int found = 0;
C
Casey Schaufler 已提交
3401 3402
	int acat;
	int kcat;
3403

3404
	if ((sap->flags & NETLBL_SECATTR_MLS_LVL) != 0) {
3405
		/*
3406
		 * Looks like a CIPSO packet.
3407 3408 3409
		 * If there are flags but no level netlabel isn't
		 * behaving the way we expect it to.
		 *
3410
		 * Look it up in the label table
3411 3412 3413 3414
		 * Without guidance regarding the smack value
		 * for the packet fall back on the network
		 * ambient value.
		 */
3415
		rcu_read_lock();
3416 3417
		list_for_each_entry(skp, &smack_known_list, list) {
			if (sap->attr.mls.lvl != skp->smk_netlabel.attr.mls.lvl)
3418
				continue;
C
Casey Schaufler 已提交
3419 3420 3421 3422 3423 3424 3425 3426 3427 3428
			/*
			 * 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; ) {
3429 3430 3431
				acat = netlbl_catmap_walk(sap->attr.mls.cat,
							  acat + 1);
				kcat = netlbl_catmap_walk(
C
Casey Schaufler 已提交
3432 3433 3434 3435 3436 3437 3438 3439 3440
					skp->smk_netlabel.attr.mls.cat,
					kcat + 1);
				if (acat < 0 || kcat < 0)
					break;
			}
			if (acat == kcat) {
				found = 1;
				break;
			}
3441
		}
3442 3443 3444
		rcu_read_unlock();

		if (found)
3445
			return skp;
3446

3447
		if (ssp != NULL && ssp->smk_in == &smack_known_star)
3448 3449
			return &smack_known_web;
		return &smack_known_star;
3450
	}
3451 3452 3453 3454
	if ((sap->flags & NETLBL_SECATTR_SECID) != 0) {
		/*
		 * Looks like a fallback, which gives us a secid.
		 */
3455
		skp = smack_from_secid(sap->attr.secid);
3456 3457 3458 3459 3460 3461 3462
		/*
		 * This has got to be a bug because it is
		 * impossible to specify a fallback without
		 * specifying the label, which will ensure
		 * it has a secid, and the only way to get a
		 * secid is from a fallback.
		 */
3463 3464
		BUG_ON(skp == NULL);
		return skp;
3465 3466
	}
	/*
3467 3468 3469
	 * Without guidance regarding the smack value
	 * for the packet fall back on the network
	 * ambient value.
3470
	 */
3471
	return smack_net_ambient;
3472 3473
}

3474
static int smk_skb_to_addr_ipv6(struct sk_buff *skb, struct sockaddr_in6 *sip)
3475 3476 3477 3478 3479 3480 3481 3482 3483 3484 3485 3486 3487 3488 3489 3490 3491 3492 3493 3494 3495 3496 3497 3498 3499 3500 3501 3502 3503 3504 3505 3506 3507 3508 3509 3510 3511 3512 3513 3514 3515 3516 3517 3518 3519 3520
{
	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;
}

3521 3522 3523 3524 3525 3526 3527 3528 3529 3530 3531
/**
 * 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;
3532
	struct smack_known *skp;
3533
	struct sockaddr_in6 sadd;
3534
	int rc = 0;
E
Etienne Basset 已提交
3535
	struct smk_audit_info ad;
3536
#ifdef CONFIG_AUDIT
3537
	struct lsm_network_audit net;
3538
#endif
3539 3540 3541 3542 3543 3544
	switch (sk->sk_family) {
	case PF_INET:
		/*
		 * Translate what netlabel gave us.
		 */
		netlbl_secattr_init(&secattr);
3545

3546 3547
		rc = netlbl_skbuff_getattr(skb, sk->sk_family, &secattr);
		if (rc == 0)
3548
			skp = smack_from_secattr(&secattr, ssp);
3549
		else
3550
			skp = smack_net_ambient;
3551

3552
		netlbl_secattr_destroy(&secattr);
3553

E
Etienne Basset 已提交
3554
#ifdef CONFIG_AUDIT
3555 3556 3557 3558
		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
3559
#endif
3560 3561 3562 3563 3564 3565
		/*
		 * 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.
		 */
3566 3567
		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
3568
					MAY_WRITE, rc);
3569 3570 3571 3572 3573 3574 3575 3576 3577 3578 3579
		if (rc != 0)
			netlbl_skbuff_err(skb, rc, 0);
		break;
	case PF_INET6:
		rc = smk_skb_to_addr_ipv6(skb, &sadd);
		if (rc == IPPROTO_UDP || rc == IPPROTO_TCP)
			rc = smk_ipv6_port_check(sk, &sadd, SMK_RECEIVING);
		else
			rc = 0;
		break;
	}
3580
	return rc;
3581 3582 3583 3584 3585 3586 3587
}

/**
 * smack_socket_getpeersec_stream - pull in packet label
 * @sock: the socket
 * @optval: user's destination
 * @optlen: size thereof
3588
 * @len: max thereof
3589 3590 3591 3592 3593 3594 3595 3596
 *
 * 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;
3597 3598
	char *rcp = "";
	int slen = 1;
3599 3600 3601
	int rc = 0;

	ssp = sock->sk->sk_security;
3602
	if (ssp->smk_packet != NULL) {
3603
		rcp = ssp->smk_packet->smk_known;
3604 3605
		slen = strlen(rcp) + 1;
	}
3606 3607 3608

	if (slen > len)
		rc = -ERANGE;
3609
	else if (copy_to_user(optval, rcp, slen) != 0)
3610 3611 3612 3613 3614 3615 3616 3617 3618 3619 3620
		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
3621
 * @sock: the peer socket
3622 3623 3624 3625 3626 3627 3628 3629 3630 3631
 * @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;
3632
	struct socket_smack *ssp = NULL;
3633
	struct smack_known *skp;
C
Casey Schaufler 已提交
3634 3635
	int family = PF_UNSPEC;
	u32 s = 0;	/* 0 is the invalid secid */
3636 3637
	int rc;

C
Casey Schaufler 已提交
3638 3639 3640 3641 3642
	if (skb != NULL) {
		if (skb->protocol == htons(ETH_P_IP))
			family = PF_INET;
		else if (skb->protocol == htons(ETH_P_IPV6))
			family = PF_INET6;
3643
	}
C
Casey Schaufler 已提交
3644 3645
	if (family == PF_UNSPEC && sock != NULL)
		family = sock->sk->sk_family;
3646

C
Casey Schaufler 已提交
3647
	if (family == PF_UNIX) {
3648
		ssp = sock->sk->sk_security;
3649
		s = ssp->smk_out->smk_secid;
C
Casey Schaufler 已提交
3650 3651 3652 3653
	} else if (family == PF_INET || family == PF_INET6) {
		/*
		 * Translate what netlabel gave us.
		 */
3654 3655
		if (sock != NULL && sock->sk != NULL)
			ssp = sock->sk->sk_security;
C
Casey Schaufler 已提交
3656 3657 3658
		netlbl_secattr_init(&secattr);
		rc = netlbl_skbuff_getattr(skb, family, &secattr);
		if (rc == 0) {
3659 3660
			skp = smack_from_secattr(&secattr, ssp);
			s = skp->smk_secid;
C
Casey Schaufler 已提交
3661 3662 3663 3664
		}
		netlbl_secattr_destroy(&secattr);
	}
	*secid = s;
3665 3666 3667 3668 3669 3670
	if (s == 0)
		return -EINVAL;
	return 0;
}

/**
3671 3672 3673
 * smack_sock_graft - Initialize a newly created socket with an existing sock
 * @sk: child sock
 * @parent: parent socket
3674
 *
3675 3676
 * Set the smk_{in,out} state of an existing sock based on the process that
 * is creating the new socket.
3677 3678 3679 3680
 */
static void smack_sock_graft(struct sock *sk, struct socket *parent)
{
	struct socket_smack *ssp;
3681
	struct smack_known *skp = smk_of_current();
3682

3683 3684
	if (sk == NULL ||
	    (sk->sk_family != PF_INET && sk->sk_family != PF_INET6))
3685 3686 3687
		return;

	ssp = sk->sk_security;
3688
	ssp->smk_in = skp;
3689
	ssp->smk_out = skp;
3690
	/* cssp->smk_packet is already set in smack_inet_csk_clone() */
3691 3692 3693 3694 3695 3696 3697 3698 3699 3700 3701 3702 3703 3704
}

/**
 * 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)
{
3705
	u16 family = sk->sk_family;
3706
	struct smack_known *skp;
3707
	struct socket_smack *ssp = sk->sk_security;
3708 3709 3710
	struct netlbl_lsm_secattr secattr;
	struct sockaddr_in addr;
	struct iphdr *hdr;
3711
	struct smack_known *hskp;
3712
	int rc;
E
Etienne Basset 已提交
3713
	struct smk_audit_info ad;
3714
#ifdef CONFIG_AUDIT
3715
	struct lsm_network_audit net;
3716
#endif
3717

3718 3719 3720 3721 3722 3723 3724 3725 3726 3727 3728
	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;
	}
3729

3730 3731
	netlbl_secattr_init(&secattr);
	rc = netlbl_skbuff_getattr(skb, family, &secattr);
3732
	if (rc == 0)
3733
		skp = smack_from_secattr(&secattr, ssp);
3734
	else
3735
		skp = &smack_known_huh;
3736 3737
	netlbl_secattr_destroy(&secattr);

E
Etienne Basset 已提交
3738
#ifdef CONFIG_AUDIT
3739 3740 3741
	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
3742 3743
	ipv4_skb_to_auditdata(skb, &ad.a, NULL);
#endif
3744
	/*
3745 3746
	 * Receiving a packet requires that the other end be able to write
	 * here. Read access is not required.
3747
	 */
3748 3749
	rc = smk_access(skp, ssp->smk_in, MAY_WRITE, &ad);
	rc = smk_bu_note("IPv4 connect", skp, ssp->smk_in, MAY_WRITE, rc);
3750 3751 3752 3753 3754 3755 3756
	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.
	 */
3757
	req->peer_secid = skp->smk_secid;
3758 3759 3760 3761

	/*
	 * 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
3762
	 * propagate the wire-label to the sock when it is created.
3763 3764 3765 3766
	 */
	hdr = ip_hdr(skb);
	addr.sin_addr.s_addr = hdr->saddr;
	rcu_read_lock();
3767
	hskp = smack_host_label(&addr);
3768 3769
	rcu_read_unlock();

3770
	if (hskp == NULL)
3771
		rc = netlbl_req_setattr(req, &skp->smk_netlabel);
3772
	else
3773
		netlbl_req_delattr(req);
3774 3775 3776 3777

	return rc;
}

3778 3779 3780 3781 3782 3783 3784 3785 3786 3787 3788
/**
 * 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;
3789
	struct smack_known *skp;
3790

3791 3792
	if (req->peer_secid != 0) {
		skp = smack_from_secid(req->peer_secid);
3793
		ssp->smk_packet = skp;
3794
	} else
3795
		ssp->smk_packet = NULL;
3796 3797
}

3798 3799 3800 3801 3802 3803 3804 3805 3806 3807 3808 3809
/*
 * 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
3810
 * @cred: the credentials to use
3811 3812 3813 3814 3815 3816
 * @flags: unused
 *
 * No allocation required
 *
 * Returns 0
 */
D
David Howells 已提交
3817
static int smack_key_alloc(struct key *key, const struct cred *cred,
3818 3819
			   unsigned long flags)
{
3820 3821
	struct smack_known *skp = smk_of_task(cred->security);

3822
	key->security = skp;
3823 3824 3825 3826 3827 3828 3829 3830 3831 3832 3833 3834 3835 3836 3837 3838 3839
	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;
}

/*
 * smack_key_permission - Smack access on a key
 * @key_ref: gets to the object
D
David Howells 已提交
3840
 * @cred: the credentials to use
3841 3842 3843 3844 3845 3846
 * @perm: unused
 *
 * 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,
3847
				const struct cred *cred, unsigned perm)
3848 3849
{
	struct key *keyp;
E
Etienne Basset 已提交
3850
	struct smk_audit_info ad;
3851
	struct smack_known *tkp = smk_of_task(cred->security);
3852
	int request = 0;
C
Casey Schaufler 已提交
3853
	int rc;
3854 3855 3856 3857 3858 3859 3860 3861 3862 3863 3864 3865 3866

	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
	 */
3867
	if (tkp == NULL)
3868
		return -EACCES;
E
Etienne Basset 已提交
3869 3870 3871 3872 3873
#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
3874 3875 3876 3877
	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
3878 3879 3880
	rc = smk_access(tkp, keyp->security, request, &ad);
	rc = smk_bu_note("key access", tkp, keyp->security, request, rc);
	return rc;
3881 3882 3883
}
#endif /* CONFIG_KEYS */

3884 3885 3886 3887 3888 3889 3890 3891 3892 3893 3894 3895 3896 3897 3898 3899 3900 3901 3902 3903 3904 3905 3906 3907 3908 3909 3910
/*
 * 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)
{
3911
	struct smack_known *skp;
3912 3913 3914 3915 3916 3917
	char **rule = (char **)vrule;
	*rule = NULL;

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

3918
	if (op != Audit_equal && op != Audit_not_equal)
3919 3920
		return -EINVAL;

3921 3922 3923
	skp = smk_import_entry(rulestr, 0);
	if (skp)
		*rule = skp->smk_known;
3924 3925 3926 3927 3928 3929 3930 3931 3932 3933 3934 3935 3936 3937 3938 3939 3940 3941 3942 3943 3944 3945 3946 3947 3948 3949 3950 3951 3952 3953 3954 3955 3956 3957 3958 3959 3960 3961 3962 3963 3964

	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)
{
3965
	struct smack_known *skp;
3966 3967
	char *rule = vrule;

3968 3969
	if (unlikely(!rule)) {
		WARN_ONCE(1, "Smack: missing rule\n");
3970 3971 3972 3973 3974 3975
		return -ENOENT;
	}

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

3976
	skp = smack_from_secid(secid);
3977 3978 3979 3980 3981 3982

	/*
	 * No need to do string comparisons. If a match occurs,
	 * both pointers will point to the same smack_known
	 * label.
	 */
3983
	if (op == Audit_equal)
3984
		return (rule == skp->smk_known);
3985
	if (op == Audit_not_equal)
3986
		return (rule != skp->smk_known);
3987 3988 3989 3990 3991 3992 3993 3994 3995 3996 3997 3998 3999 4000 4001 4002 4003

	return 0;
}

/**
 * smack_audit_rule_free - free smack rule representation
 * @vrule: rule to be freed.
 *
 * No memory was allocated.
 */
static void smack_audit_rule_free(void *vrule)
{
	/* No-op */
}

#endif /* CONFIG_AUDIT */

4004 4005 4006 4007 4008 4009 4010 4011 4012 4013
/**
 * 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);
}


4014
/**
4015 4016 4017 4018 4019 4020 4021 4022 4023
 * 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)
{
4024
	struct smack_known *skp = smack_from_secid(secid);
4025

4026
	if (secdata)
4027 4028
		*secdata = skp->smk_known;
	*seclen = strlen(skp->smk_known);
4029 4030 4031
	return 0;
}

4032
/**
4033 4034 4035 4036 4037 4038 4039
 * 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.
 */
4040
static int smack_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
4041
{
4042 4043 4044 4045 4046 4047
	struct smack_known *skp = smk_find_entry(secdata);

	if (skp)
		*secid = skp->smk_secid;
	else
		*secid = 0;
4048 4049 4050
	return 0;
}

4051
/**
4052
 * smack_release_secctx - don't do anything.
4053 4054
 * @secdata: unused
 * @seclen: unused
4055 4056 4057 4058 4059 4060 4061
 *
 * Exists to make sure nothing gets done, and properly
 */
static void smack_release_secctx(char *secdata, u32 seclen)
{
}

4062 4063 4064 4065 4066 4067 4068 4069 4070 4071 4072 4073 4074 4075 4076 4077 4078 4079 4080 4081 4082
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;
}

4083 4084 4085
struct security_operations smack_ops = {
	.name =				"smack",

4086
	.ptrace_access_check =		smack_ptrace_access_check,
4087
	.ptrace_traceme =		smack_ptrace_traceme,
4088 4089 4090 4091 4092 4093 4094 4095
	.syslog = 			smack_syslog,

	.sb_alloc_security = 		smack_sb_alloc_security,
	.sb_free_security = 		smack_sb_free_security,
	.sb_copy_data = 		smack_sb_copy_data,
	.sb_kern_mount = 		smack_sb_kern_mount,
	.sb_statfs = 			smack_sb_statfs,

4096
	.bprm_set_creds =		smack_bprm_set_creds,
4097 4098
	.bprm_committing_creds =	smack_bprm_committing_creds,
	.bprm_secureexec =		smack_bprm_secureexec,
4099

4100 4101 4102 4103 4104 4105 4106 4107 4108 4109 4110 4111 4112 4113 4114 4115 4116
	.inode_alloc_security = 	smack_inode_alloc_security,
	.inode_free_security = 		smack_inode_free_security,
	.inode_init_security = 		smack_inode_init_security,
	.inode_link = 			smack_inode_link,
	.inode_unlink = 		smack_inode_unlink,
	.inode_rmdir = 			smack_inode_rmdir,
	.inode_rename = 		smack_inode_rename,
	.inode_permission = 		smack_inode_permission,
	.inode_setattr = 		smack_inode_setattr,
	.inode_getattr = 		smack_inode_getattr,
	.inode_setxattr = 		smack_inode_setxattr,
	.inode_post_setxattr = 		smack_inode_post_setxattr,
	.inode_getxattr = 		smack_inode_getxattr,
	.inode_removexattr = 		smack_inode_removexattr,
	.inode_getsecurity = 		smack_inode_getsecurity,
	.inode_setsecurity = 		smack_inode_setsecurity,
	.inode_listsecurity = 		smack_inode_listsecurity,
4117
	.inode_getsecid =		smack_inode_getsecid,
4118 4119 4120 4121 4122 4123 4124

	.file_permission = 		smack_file_permission,
	.file_alloc_security = 		smack_file_alloc_security,
	.file_free_security = 		smack_file_free_security,
	.file_ioctl = 			smack_file_ioctl,
	.file_lock = 			smack_file_lock,
	.file_fcntl = 			smack_file_fcntl,
4125 4126
	.mmap_file =			smack_mmap_file,
	.mmap_addr =			cap_mmap_addr,
4127 4128 4129 4130
	.file_set_fowner = 		smack_file_set_fowner,
	.file_send_sigiotask = 		smack_file_send_sigiotask,
	.file_receive = 		smack_file_receive,

4131
	.file_open =			smack_file_open,
4132

4133
	.cred_alloc_blank =		smack_cred_alloc_blank,
4134
	.cred_free =			smack_cred_free,
D
David Howells 已提交
4135
	.cred_prepare =			smack_cred_prepare,
4136
	.cred_transfer =		smack_cred_transfer,
4137 4138
	.kernel_act_as =		smack_kernel_act_as,
	.kernel_create_files_as =	smack_kernel_create_files_as,
4139 4140 4141 4142 4143 4144 4145 4146 4147 4148 4149 4150 4151 4152 4153
	.task_setpgid = 		smack_task_setpgid,
	.task_getpgid = 		smack_task_getpgid,
	.task_getsid = 			smack_task_getsid,
	.task_getsecid = 		smack_task_getsecid,
	.task_setnice = 		smack_task_setnice,
	.task_setioprio = 		smack_task_setioprio,
	.task_getioprio = 		smack_task_getioprio,
	.task_setscheduler = 		smack_task_setscheduler,
	.task_getscheduler = 		smack_task_getscheduler,
	.task_movememory = 		smack_task_movememory,
	.task_kill = 			smack_task_kill,
	.task_wait = 			smack_task_wait,
	.task_to_inode = 		smack_task_to_inode,

	.ipc_permission = 		smack_ipc_permission,
4154
	.ipc_getsecid =			smack_ipc_getsecid,
4155 4156 4157 4158 4159 4160 4161 4162 4163 4164 4165 4166 4167 4168 4169 4170 4171 4172 4173 4174 4175 4176 4177 4178 4179 4180 4181 4182 4183 4184 4185 4186

	.msg_msg_alloc_security = 	smack_msg_msg_alloc_security,
	.msg_msg_free_security = 	smack_msg_msg_free_security,

	.msg_queue_alloc_security = 	smack_msg_queue_alloc_security,
	.msg_queue_free_security = 	smack_msg_queue_free_security,
	.msg_queue_associate = 		smack_msg_queue_associate,
	.msg_queue_msgctl = 		smack_msg_queue_msgctl,
	.msg_queue_msgsnd = 		smack_msg_queue_msgsnd,
	.msg_queue_msgrcv = 		smack_msg_queue_msgrcv,

	.shm_alloc_security = 		smack_shm_alloc_security,
	.shm_free_security = 		smack_shm_free_security,
	.shm_associate = 		smack_shm_associate,
	.shm_shmctl = 			smack_shm_shmctl,
	.shm_shmat = 			smack_shm_shmat,

	.sem_alloc_security = 		smack_sem_alloc_security,
	.sem_free_security = 		smack_sem_free_security,
	.sem_associate = 		smack_sem_associate,
	.sem_semctl = 			smack_sem_semctl,
	.sem_semop = 			smack_sem_semop,

	.d_instantiate = 		smack_d_instantiate,

	.getprocattr = 			smack_getprocattr,
	.setprocattr = 			smack_setprocattr,

	.unix_stream_connect = 		smack_unix_stream_connect,
	.unix_may_send = 		smack_unix_may_send,

	.socket_post_create = 		smack_socket_post_create,
4187
	.socket_bind =			smack_socket_bind,
4188 4189
	.socket_connect =		smack_socket_connect,
	.socket_sendmsg =		smack_socket_sendmsg,
4190 4191 4192 4193 4194 4195 4196
	.socket_sock_rcv_skb = 		smack_socket_sock_rcv_skb,
	.socket_getpeersec_stream =	smack_socket_getpeersec_stream,
	.socket_getpeersec_dgram =	smack_socket_getpeersec_dgram,
	.sk_alloc_security = 		smack_sk_alloc_security,
	.sk_free_security = 		smack_sk_free_security,
	.sock_graft = 			smack_sock_graft,
	.inet_conn_request = 		smack_inet_conn_request,
4197
	.inet_csk_clone =		smack_inet_csk_clone,
4198

4199 4200 4201 4202 4203 4204
 /* key management security hooks */
#ifdef CONFIG_KEYS
	.key_alloc = 			smack_key_alloc,
	.key_free = 			smack_key_free,
	.key_permission = 		smack_key_permission,
#endif /* CONFIG_KEYS */
4205 4206 4207 4208 4209 4210 4211 4212 4213

 /* Audit hooks */
#ifdef CONFIG_AUDIT
	.audit_rule_init =		smack_audit_rule_init,
	.audit_rule_known =		smack_audit_rule_known,
	.audit_rule_match =		smack_audit_rule_match,
	.audit_rule_free =		smack_audit_rule_free,
#endif /* CONFIG_AUDIT */

4214
	.ismaclabel =			smack_ismaclabel,
4215
	.secid_to_secctx = 		smack_secid_to_secctx,
4216
	.secctx_to_secid = 		smack_secctx_to_secid,
4217
	.release_secctx = 		smack_release_secctx,
4218 4219 4220
	.inode_notifysecctx =		smack_inode_notifysecctx,
	.inode_setsecctx =		smack_inode_setsecctx,
	.inode_getsecctx =		smack_inode_getsecctx,
4221 4222
};

4223

4224
static __init void init_smack_known_list(void)
4225
{
4226 4227 4228 4229 4230 4231 4232 4233 4234 4235 4236 4237 4238 4239 4240 4241 4242 4243 4244 4245 4246
	/*
	 * 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_invalid.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_invalid.smk_rules);
	INIT_LIST_HEAD(&smack_known_web.smk_rules);
	/*
	 * Create the known labels list
	 */
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	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_invalid);
	smk_insert_entry(&smack_known_web);
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}

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/**
 * smack_init - initialize the smack system
 *
 * Returns 0
 */
static __init int smack_init(void)
{
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	struct cred *cred;
4263
	struct task_smack *tsp;
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	if (!security_module_enable(&smack_ops))
		return 0;

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	smack_inode_cache = KMEM_CACHE(inode_smack, 0);
	if (!smack_inode_cache)
		return -ENOMEM;

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	tsp = new_task_smack(&smack_known_floor, &smack_known_floor,
				GFP_KERNEL);
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	if (tsp == NULL) {
		kmem_cache_destroy(smack_inode_cache);
4276
		return -ENOMEM;
4277
	}
4278

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	printk(KERN_INFO "Smack:  Initializing.\n");

	/*
	 * Set the security state for the initial task.
	 */
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	cred = (struct cred *) current->cred;
4285
	cred->security = tsp;
4286

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	/* initialize the smack_known_list */
	init_smack_known_list();
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	/*
	 * Register with LSM
	 */
	if (register_security(&smack_ops))
		panic("smack: Unable to register with kernel.\n");

	return 0;
}

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