smack_lsm.c 100.6 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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#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
static int smk_bu_note(char *note, struct smack_known *sskp, char *osp,
			int mode, int rc)
{
	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",
		sskp->smk_known, osp, acc, note);
	return 0;
}
#else
#define smk_bu_note(note, sskp, osp, mode, RC) (RC)
#endif

#ifdef CONFIG_SECURITY_SMACK_BRINGUP
static int smk_bu_current(char *note, char *osp, 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) %s %s\n",
		tsp->smk_task->smk_known, osp, acc, current->comm, note);
	return 0;
}
#else
#define smk_bu_current(note, osp, mode, RC) (RC)
#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",
		tsp->smk_task->smk_known, smk_of_inode(inode), acc,
		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);
	pr_info("Smack Bringup: (%s %s %s) file=(%s %ld %s) %s\n",
		sskp->smk_known, (char *)file->f_security, acc,
		inode->i_sb->s_id, inode->i_ino, file->f_dentry->d_name.name,
		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);
	pr_info("Smack Bringup: (%s %s %s) file=(%s %ld %s) %s\n",
		sskp->smk_known, smk_of_inode(inode), acc,
		inode->i_sb->s_id, inode->i_ino, file->f_dentry->d_name.name,
		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
 * @smack: a pointer to the Smack label to use in the blob
 *
 * Returns the new blob or NULL if there's no memory available
 */
struct inode_smack *new_inode_smack(char *smack)
{
	struct inode_smack *isp;

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	isp = kzalloc(sizeof(struct inode_smack), GFP_NOFS);
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	if (isp == NULL)
		return NULL;

	isp->smk_inode = smack;
	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_label: label of the process that's about to be traced,
 *                the pointer must originate from smack structures
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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
 */
static int smk_ptrace_rule_check(struct task_struct *tracer, char *tracee_label,
				 unsigned int mode, const char *func)
{
	int rc;
	struct smk_audit_info ad, *saip = NULL;
	struct task_smack *tsp;
	struct smack_known *skp;

	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);
	skp = 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)) {
		if (skp->smk_known == tracee_label)
			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)
			smack_log(skp->smk_known, tracee_label, 0, rc, saip);

		return rc;
	}

	/* In case of rule==SMACK_PTRACE_DEFAULT or mode==PTRACE_MODE_READ */
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	rc = smk_tskacc(tsp, tracee_label, smk_ptrace_mode(mode), saip);
	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->smk_known, 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->smk_known,
				   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;

	sbsp->smk_root = smack_known_floor.smk_known;
	sbsp->smk_default = smack_known_floor.smk_known;
	sbsp->smk_floor = smack_known_floor.smk_known;
	sbsp->smk_hat = smack_known_hat.smk_known;
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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;
	char *nsp;
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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);
			nsp = smk_import(op, 0);
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			if (nsp != NULL) {
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				sp->smk_hat = nsp;
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				specified = 1;
			}
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		} else if (strncmp(op, SMK_FSFLOOR, strlen(SMK_FSFLOOR)) == 0) {
			op += strlen(SMK_FSFLOOR);
			nsp = smk_import(op, 0);
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			if (nsp != NULL) {
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				sp->smk_floor = nsp;
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				specified = 1;
			}
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		} else if (strncmp(op, SMK_FSDEFAULT,
				   strlen(SMK_FSDEFAULT)) == 0) {
			op += strlen(SMK_FSDEFAULT);
			nsp = smk_import(op, 0);
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			if (nsp != NULL) {
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				sp->smk_default = nsp;
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				specified = 1;
			}
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		} else if (strncmp(op, SMK_FSROOT, strlen(SMK_FSROOT)) == 0) {
			op += strlen(SMK_FSROOT);
			nsp = smk_import(op, 0);
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			if (nsp != NULL) {
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				sp->smk_root = nsp;
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				specified = 1;
			}
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		} else if (strncmp(op, SMK_FSTRANS, strlen(SMK_FSTRANS)) == 0) {
			op += strlen(SMK_FSTRANS);
			nsp = smk_import(op, 0);
			if (nsp != NULL) {
				sp->smk_root = nsp;
				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();
		sp->smk_root = skp->smk_known;
		sp->smk_default = skp->smk_known;
	}
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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);
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	rc = smk_bu_current("statfs", sbp->smk_floor, MAY_READ, rc);
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	return rc;
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}

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/*
 * BPRM hooks
 */

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/**
 * smack_bprm_set_creds - set creds for exec
 * @bprm: the exec information
 *
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 * Returns 0 if it gets a blob, -EPERM if exec forbidden and -ENOMEM otherwise
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 */
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static int smack_bprm_set_creds(struct linux_binprm *bprm)
{
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	struct inode *inode = file_inode(bprm->file);
670
	struct task_smack *bsp = bprm->cred->security;
671 672 673 674 675 676 677 678 679 680
	struct inode_smack *isp;
	int rc;

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

	if (bprm->cred_prepared)
		return 0;

681 682
	isp = inode->i_security;
	if (isp->smk_task == NULL || isp->smk_task == bsp->smk_task)
683 684
		return 0;

685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700
	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,
						   isp->smk_task->smk_known,
						   PTRACE_MODE_ATTACH,
						   __func__);
		rcu_read_unlock();

		if (rc != 0)
			return rc;
	} else if (bprm->unsafe)
701
		return -EPERM;
702

703 704
	bsp->smk_task = isp->smk_task;
	bprm->per_clear |= PER_CLEAR_ON_SETID;
705

706 707
	return 0;
}
708

709 710 711 712 713 714 715 716 717
/**
 * 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;
718

719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737
	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;
738 739
}

740 741 742 743 744 745
/*
 * Inode hooks
 */

/**
 * smack_inode_alloc_security - allocate an inode blob
746
 * @inode: the inode in need of a blob
747 748 749 750 751
 *
 * Returns 0 if it gets a blob, -ENOMEM otherwise
 */
static int smack_inode_alloc_security(struct inode *inode)
{
752 753 754
	struct smack_known *skp = smk_of_current();

	inode->i_security = new_inode_smack(skp->smk_known);
755 756 757 758 759 760 761
	if (inode->i_security == NULL)
		return -ENOMEM;
	return 0;
}

/**
 * smack_inode_free_security - free an inode blob
762
 * @inode: the inode with a blob
763 764 765 766 767 768 769 770 771 772 773
 *
 * Clears the blob pointer in inode
 */
static void smack_inode_free_security(struct inode *inode)
{
	kfree(inode->i_security);
	inode->i_security = NULL;
}

/**
 * smack_inode_init_security - copy out the smack from an inode
774 775
 * @inode: the newly created inode
 * @dir: containing directory object
776
 * @qstr: unused
777 778 779 780 781 782 783
 * @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,
784
				     const struct qstr *qstr, const char **name,
785
				     void **value, size_t *len)
786
{
C
Casey Schaufler 已提交
787
	struct inode_smack *issp = inode->i_security;
788
	struct smack_known *skp = smk_of_current();
789
	char *isp = smk_of_inode(inode);
790
	char *dsp = smk_of_inode(dir);
791
	int may;
792

793 794
	if (name)
		*name = XATTR_SMACK_SUFFIX;
795 796

	if (value) {
797
		rcu_read_lock();
798
		may = smk_access_entry(skp->smk_known, dsp, &skp->smk_rules);
799
		rcu_read_unlock();
800 801 802 803 804

		/*
		 * If the access rule allows transmutation and
		 * the directory requests transmutation then
		 * by all means transmute.
C
Casey Schaufler 已提交
805
		 * Mark the inode as changed.
806
		 */
807
		if (may > 0 && ((may & MAY_TRANSMUTE) != 0) &&
C
Casey Schaufler 已提交
808
		    smk_inode_transmutable(dir)) {
809
			isp = dsp;
C
Casey Schaufler 已提交
810 811
			issp->smk_flags |= SMK_INODE_CHANGED;
		}
812

813
		*value = kstrdup(isp, GFP_NOFS);
814 815 816 817 818
		if (*value == NULL)
			return -ENOMEM;
	}

	if (len)
819
		*len = strlen(isp);
820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835

	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)
{
	char *isp;
E
Etienne Basset 已提交
836 837 838
	struct smk_audit_info ad;
	int rc;

839
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
E
Etienne Basset 已提交
840
	smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
841 842

	isp = smk_of_inode(old_dentry->d_inode);
E
Etienne Basset 已提交
843
	rc = smk_curacc(isp, MAY_WRITE, &ad);
C
Casey Schaufler 已提交
844
	rc = smk_bu_inode(old_dentry->d_inode, MAY_WRITE, rc);
845 846 847

	if (rc == 0 && new_dentry->d_inode != NULL) {
		isp = smk_of_inode(new_dentry->d_inode);
E
Etienne Basset 已提交
848 849
		smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
		rc = smk_curacc(isp, MAY_WRITE, &ad);
C
Casey Schaufler 已提交
850
		rc = smk_bu_inode(new_dentry->d_inode, MAY_WRITE, rc);
851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866
	}

	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
867
	struct smk_audit_info ad;
868 869
	int rc;

870
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
E
Etienne Basset 已提交
871 872
	smk_ad_setfield_u_fs_path_dentry(&ad, dentry);

873 874 875
	/*
	 * You need write access to the thing you're unlinking
	 */
E
Etienne Basset 已提交
876
	rc = smk_curacc(smk_of_inode(ip), MAY_WRITE, &ad);
C
Casey Schaufler 已提交
877
	rc = smk_bu_inode(ip, MAY_WRITE, rc);
E
Etienne Basset 已提交
878
	if (rc == 0) {
879 880 881
		/*
		 * You also need write access to the containing directory
		 */
882
		smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
E
Etienne Basset 已提交
883 884
		smk_ad_setfield_u_fs_inode(&ad, dir);
		rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad);
C
Casey Schaufler 已提交
885
		rc = smk_bu_inode(dir, MAY_WRITE, rc);
E
Etienne Basset 已提交
886
	}
887 888 889 890 891 892 893 894 895 896 897 898 899
	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
900
	struct smk_audit_info ad;
901 902
	int rc;

903
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
E
Etienne Basset 已提交
904 905
	smk_ad_setfield_u_fs_path_dentry(&ad, dentry);

906 907 908
	/*
	 * You need write access to the thing you're removing
	 */
E
Etienne Basset 已提交
909
	rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
C
Casey Schaufler 已提交
910
	rc = smk_bu_inode(dentry->d_inode, MAY_WRITE, rc);
E
Etienne Basset 已提交
911
	if (rc == 0) {
912 913 914
		/*
		 * You also need write access to the containing directory
		 */
915
		smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
E
Etienne Basset 已提交
916 917
		smk_ad_setfield_u_fs_inode(&ad, dir);
		rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad);
C
Casey Schaufler 已提交
918
		rc = smk_bu_inode(dir, MAY_WRITE, rc);
E
Etienne Basset 已提交
919
	}
920 921 922 923 924 925

	return rc;
}

/**
 * smack_inode_rename - Smack check on rename
926 927 928 929
 * @old_inode: unused
 * @old_dentry: the old object
 * @new_inode: unused
 * @new_dentry: the new object
930 931 932 933 934 935 936 937 938 939 940 941 942
 *
 * 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;
	char *isp;
E
Etienne Basset 已提交
943 944
	struct smk_audit_info ad;

945
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
E
Etienne Basset 已提交
946
	smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
947 948

	isp = smk_of_inode(old_dentry->d_inode);
E
Etienne Basset 已提交
949
	rc = smk_curacc(isp, MAY_READWRITE, &ad);
C
Casey Schaufler 已提交
950
	rc = smk_bu_inode(old_dentry->d_inode, MAY_READWRITE, rc);
951 952 953

	if (rc == 0 && new_dentry->d_inode != NULL) {
		isp = smk_of_inode(new_dentry->d_inode);
E
Etienne Basset 已提交
954 955
		smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
		rc = smk_curacc(isp, MAY_READWRITE, &ad);
C
Casey Schaufler 已提交
956
		rc = smk_bu_inode(new_dentry->d_inode, MAY_READWRITE, rc);
957 958 959 960 961 962 963 964 965 966 967 968 969
	}
	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
 */
970
static int smack_inode_permission(struct inode *inode, int mask)
971
{
E
Etienne Basset 已提交
972
	struct smk_audit_info ad;
973
	int no_block = mask & MAY_NOT_BLOCK;
C
Casey Schaufler 已提交
974
	int rc;
975 976

	mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
977 978 979 980 981
	/*
	 * No permission to check. Existence test. Yup, it's there.
	 */
	if (mask == 0)
		return 0;
982 983

	/* May be droppable after audit */
984
	if (no_block)
985
		return -ECHILD;
986
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
E
Etienne Basset 已提交
987
	smk_ad_setfield_u_fs_inode(&ad, inode);
C
Casey Schaufler 已提交
988 989 990
	rc = smk_curacc(smk_of_inode(inode), mask, &ad);
	rc = smk_bu_inode(inode, mask, rc);
	return rc;
991 992 993 994 995 996 997 998 999 1000 1001
}

/**
 * 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
1002
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
1003 1004
	int rc;

1005 1006 1007 1008 1009
	/*
	 * Need to allow for clearing the setuid bit.
	 */
	if (iattr->ia_valid & ATTR_FORCE)
		return 0;
1010
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
E
Etienne Basset 已提交
1011
	smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1012

C
Casey Schaufler 已提交
1013 1014 1015
	rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
	rc = smk_bu_inode(dentry->d_inode, MAY_WRITE, rc);
	return rc;
1016 1017 1018 1019
}

/**
 * smack_inode_getattr - Smack check for getting attributes
1020
 * @mnt: vfsmount of the object
1021 1022 1023 1024 1025 1026
 * @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
1027
	struct smk_audit_info ad;
1028
	struct path path;
C
Casey Schaufler 已提交
1029
	int rc;
E
Etienne Basset 已提交
1030

1031 1032
	path.dentry = dentry;
	path.mnt = mnt;
E
Etienne Basset 已提交
1033

1034
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1035
	smk_ad_setfield_u_fs_path(&ad, path);
C
Casey Schaufler 已提交
1036 1037 1038
	rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ, &ad);
	rc = smk_bu_inode(dentry->d_inode, MAY_READ, rc);
	return rc;
1039 1040 1041 1042 1043 1044
}

/**
 * smack_inode_setxattr - Smack check for setting xattrs
 * @dentry: the object
 * @name: name of the attribute
1045 1046
 * @value: value of the attribute
 * @size: size of the value
1047 1048 1049 1050 1051 1052
 * @flags: unused
 *
 * This protects the Smack attribute explicitly.
 *
 * Returns 0 if access is permitted, an error code otherwise
 */
1053 1054
static int smack_inode_setxattr(struct dentry *dentry, const char *name,
				const void *value, size_t size, int flags)
1055
{
E
Etienne Basset 已提交
1056
	struct smk_audit_info ad;
1057 1058 1059 1060
	struct smack_known *skp;
	int check_priv = 0;
	int check_import = 0;
	int check_star = 0;
1061
	int rc = 0;
1062

1063 1064 1065
	/*
	 * Check label validity here so import won't fail in post_setxattr
	 */
1066 1067
	if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
	    strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
1068 1069 1070 1071 1072 1073 1074 1075
	    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;
1076
	} else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) {
1077
		check_priv = 1;
1078 1079 1080
		if (size != TRANS_TRUE_SIZE ||
		    strncmp(value, TRANS_TRUE, TRANS_TRUE_SIZE) != 0)
			rc = -EINVAL;
1081 1082 1083
	} else
		rc = cap_inode_setxattr(dentry, name, value, size, flags);

1084 1085 1086 1087
	if (check_priv && !smack_privileged(CAP_MAC_ADMIN))
		rc = -EPERM;

	if (rc == 0 && check_import) {
1088
		skp = size ? smk_import_entry(value, size) : NULL;
1089 1090 1091 1092 1093
		if (skp == NULL || (check_star &&
		    (skp == &smack_known_star || skp == &smack_known_web)))
			rc = -EINVAL;
	}

1094
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
E
Etienne Basset 已提交
1095 1096
	smk_ad_setfield_u_fs_path_dentry(&ad, dentry);

C
Casey Schaufler 已提交
1097
	if (rc == 0) {
E
Etienne Basset 已提交
1098
		rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
C
Casey Schaufler 已提交
1099 1100
		rc = smk_bu_inode(dentry->d_inode, MAY_WRITE, rc);
	}
1101 1102

	return rc;
1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115
}

/**
 * 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.
 */
1116 1117
static void smack_inode_post_setxattr(struct dentry *dentry, const char *name,
				      const void *value, size_t size, int flags)
1118
{
1119
	struct smack_known *skp;
1120
	struct inode_smack *isp = dentry->d_inode->i_security;
1121

1122 1123 1124 1125 1126
	if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) {
		isp->smk_flags |= SMK_INODE_TRANSMUTE;
		return;
	}

1127
	if (strcmp(name, XATTR_NAME_SMACK) == 0) {
1128
		skp = smk_import_entry(value, size);
1129 1130
		if (skp != NULL)
			isp->smk_inode = skp->smk_known;
1131 1132
		else
			isp->smk_inode = smack_known_invalid.smk_known;
1133
	} else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0) {
1134
		skp = smk_import_entry(value, size);
1135 1136
		if (skp != NULL)
			isp->smk_task = skp;
1137
		else
1138
			isp->smk_task = &smack_known_invalid;
1139
	} else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
1140
		skp = smk_import_entry(value, size);
1141 1142
		if (skp != NULL)
			isp->smk_mmap = skp;
1143
		else
1144 1145
			isp->smk_mmap = &smack_known_invalid;
	}
1146 1147 1148 1149

	return;
}

C
Casey Schaufler 已提交
1150
/**
1151 1152 1153 1154 1155 1156
 * smack_inode_getxattr - Smack check on getxattr
 * @dentry: the object
 * @name: unused
 *
 * Returns 0 if access is permitted, an error code otherwise
 */
1157
static int smack_inode_getxattr(struct dentry *dentry, const char *name)
1158
{
E
Etienne Basset 已提交
1159
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
1160
	int rc;
E
Etienne Basset 已提交
1161

1162
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
E
Etienne Basset 已提交
1163 1164
	smk_ad_setfield_u_fs_path_dentry(&ad, dentry);

C
Casey Schaufler 已提交
1165 1166 1167
	rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ, &ad);
	rc = smk_bu_inode(dentry->d_inode, MAY_READ, rc);
	return rc;
1168 1169
}

C
Casey Schaufler 已提交
1170
/**
1171 1172 1173 1174 1175 1176 1177 1178
 * 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
 */
1179
static int smack_inode_removexattr(struct dentry *dentry, const char *name)
1180
{
1181
	struct inode_smack *isp;
E
Etienne Basset 已提交
1182
	struct smk_audit_info ad;
1183
	int rc = 0;
1184

1185 1186
	if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
	    strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
1187
	    strcmp(name, XATTR_NAME_SMACKIPOUT) == 0 ||
1188
	    strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
1189
	    strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0 ||
P
Pankaj Kumar 已提交
1190
	    strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
1191
		if (!smack_privileged(CAP_MAC_ADMIN))
1192 1193 1194 1195
			rc = -EPERM;
	} else
		rc = cap_inode_removexattr(dentry, name);

1196 1197 1198
	if (rc != 0)
		return rc;

1199
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
E
Etienne Basset 已提交
1200
	smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1201

1202
	rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
C
Casey Schaufler 已提交
1203
	rc = smk_bu_inode(dentry->d_inode, MAY_WRITE, rc);
1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214
	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)
1215
		isp->smk_task = NULL;
1216
	else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0)
1217
		isp->smk_mmap = NULL;
1218 1219
	else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0)
		isp->smk_flags &= ~SMK_INODE_TRANSMUTE;
1220

1221
	return 0;
1222 1223 1224 1225 1226 1227 1228
}

/**
 * smack_inode_getsecurity - get smack xattrs
 * @inode: the object
 * @name: attribute name
 * @buffer: where to put the result
1229
 * @alloc: unused
1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246
 *
 * 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;
	char *isp;
	int ilen;
	int rc = 0;

	if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
		isp = smk_of_inode(inode);
1247
		ilen = strlen(isp);
1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259
		*buffer = isp;
		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);
1260
	if (sock == NULL || sock->sk == NULL)
1261 1262 1263 1264 1265
		return -EOPNOTSUPP;

	ssp = sock->sk->sk_security;

	if (strcmp(name, XATTR_SMACK_IPIN) == 0)
1266
		isp = ssp->smk_in->smk_known;
1267
	else if (strcmp(name, XATTR_SMACK_IPOUT) == 0)
1268
		isp = ssp->smk_out->smk_known;
1269 1270 1271
	else
		return -EOPNOTSUPP;

1272
	ilen = strlen(isp);
1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292
	if (rc == 0) {
		*buffer = isp;
		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)
{
1293
	int len = sizeof(XATTR_NAME_SMACK);
1294

1295
	if (buffer != NULL && len <= buffer_size)
1296
		memcpy(buffer, XATTR_NAME_SMACK, len);
1297 1298

	return len;
1299 1300
}

1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312
/**
 * 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;

	*secid = smack_to_secid(isp->smk_inode);
}

1313 1314 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
/*
 * 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)
{
1347 1348 1349
	struct smack_known *skp = smk_of_current();

	file->f_security = skp->smk_known;
1350 1351 1352 1353 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
	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
1379 1380
	struct smk_audit_info ad;

1381
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
E
Etienne Basset 已提交
1382
	smk_ad_setfield_u_fs_path(&ad, file->f_path);
1383

C
Casey Schaufler 已提交
1384
	if (_IOC_DIR(cmd) & _IOC_WRITE) {
E
Etienne Basset 已提交
1385
		rc = smk_curacc(file->f_security, MAY_WRITE, &ad);
C
Casey Schaufler 已提交
1386 1387
		rc = smk_bu_file(file, MAY_WRITE, rc);
	}
1388

C
Casey Schaufler 已提交
1389
	if (rc == 0 && (_IOC_DIR(cmd) & _IOC_READ)) {
E
Etienne Basset 已提交
1390
		rc = smk_curacc(file->f_security, MAY_READ, &ad);
C
Casey Schaufler 已提交
1391 1392
		rc = smk_bu_file(file, MAY_READ, rc);
	}
1393 1394 1395 1396 1397 1398 1399

	return rc;
}

/**
 * smack_file_lock - Smack check on file locking
 * @file: the object
1400
 * @cmd: unused
1401
 *
1402
 * Returns 0 if current has lock access, error code otherwise
1403 1404 1405
 */
static int smack_file_lock(struct file *file, unsigned int cmd)
{
E
Etienne Basset 已提交
1406
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
1407
	int rc;
E
Etienne Basset 已提交
1408

1409 1410
	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
1411 1412 1413
	rc = smk_curacc(file->f_security, MAY_LOCK, &ad);
	rc = smk_bu_file(file, MAY_LOCK, rc);
	return rc;
1414 1415 1416 1417 1418 1419 1420 1421
}

/**
 * smack_file_fcntl - Smack check on fcntl
 * @file: the object
 * @cmd: what action to check
 * @arg: unused
 *
1422 1423 1424 1425
 * Generally these operations are harmless.
 * File locking operations present an obvious mechanism
 * for passing information, so they require write access.
 *
1426 1427 1428 1429 1430
 * 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
1431
	struct smk_audit_info ad;
1432
	int rc = 0;
1433

E
Etienne Basset 已提交
1434

1435 1436
	switch (cmd) {
	case F_GETLK:
1437
		break;
1438 1439
	case F_SETLK:
	case F_SETLKW:
1440 1441 1442
		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
1443
		rc = smk_bu_file(file, MAY_LOCK, rc);
1444
		break;
1445 1446
	case F_SETOWN:
	case F_SETSIG:
1447 1448
		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
1449
		rc = smk_curacc(file->f_security, MAY_WRITE, &ad);
C
Casey Schaufler 已提交
1450
		rc = smk_bu_file(file, MAY_WRITE, rc);
1451 1452
		break;
	default:
1453
		break;
1454 1455 1456 1457 1458
	}

	return rc;
}

1459
/**
1460
 * smack_mmap_file :
1461 1462 1463 1464 1465 1466 1467 1468
 * 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.
 */
1469
static int smack_mmap_file(struct file *file,
1470
			   unsigned long reqprot, unsigned long prot,
1471
			   unsigned long flags)
1472
{
1473
	struct smack_known *skp;
1474
	struct smack_known *mkp;
1475 1476
	struct smack_rule *srp;
	struct task_smack *tsp;
1477
	char *osmack;
1478
	struct inode_smack *isp;
1479 1480 1481
	int may;
	int mmay;
	int tmay;
1482 1483
	int rc;

A
Al Viro 已提交
1484
	if (file == NULL)
1485 1486
		return 0;

A
Al Viro 已提交
1487
	isp = file_inode(file)->i_security;
1488 1489
	if (isp->smk_mmap == NULL)
		return 0;
1490
	mkp = isp->smk_mmap;
1491 1492

	tsp = current_security();
1493
	skp = smk_of_current();
1494 1495 1496 1497 1498 1499 1500 1501
	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.
	 */
1502
	list_for_each_entry_rcu(srp, &skp->smk_rules, list) {
1503
		osmack = srp->smk_object;
1504 1505 1506
		/*
		 * Matching labels always allows access.
		 */
1507
		if (mkp->smk_known == osmack)
1508
			continue;
1509 1510 1511 1512
		/*
		 * If there is a matching local rule take
		 * that into account as well.
		 */
1513
		may = smk_access_entry(srp->smk_subject->smk_known, osmack,
1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530
					&tsp->smk_rules);
		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.
		 */
1531 1532
		mmay = smk_access_entry(mkp->smk_known, osmack,
						&mkp->smk_rules);
1533 1534 1535 1536 1537 1538 1539 1540
		if (mmay == -ENOENT) {
			rc = -EACCES;
			break;
		}
		/*
		 * If there is a local entry it modifies the
		 * potential access, too.
		 */
1541 1542
		tmay = smk_access_entry(mkp->smk_known, osmack,
						&tsp->smk_rules);
1543 1544
		if (tmay != -ENOENT)
			mmay &= tmay;
1545

1546 1547 1548 1549 1550
		/*
		 * If there is any access available to current that is
		 * not available to a SMACK64MMAP subject
		 * deny access.
		 */
1551
		if ((may | mmay) != mmay) {
1552
			rc = -EACCES;
1553
			break;
1554
		}
1555 1556 1557 1558 1559 1560 1561
	}

	rcu_read_unlock();

	return rc;
}

1562 1563 1564 1565 1566 1567 1568 1569 1570
/**
 * smack_file_set_fowner - set the file security blob value
 * @file: object in question
 *
 * Returns 0
 * Further research may be required on this one.
 */
static int smack_file_set_fowner(struct file *file)
{
1571 1572 1573
	struct smack_known *skp = smk_of_current();

	file->f_security = skp->smk_known;
1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590
	return 0;
}

/**
 * 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)
{
1591 1592
	struct smack_known *skp;
	struct smack_known *tkp = smk_of_task(tsk->cred->security);
1593 1594
	struct file *file;
	int rc;
E
Etienne Basset 已提交
1595
	struct smk_audit_info ad;
1596 1597 1598 1599 1600

	/*
	 * struct fown_struct is never outside the context of a struct file
	 */
	file = container_of(fown, struct file, f_owner);
1601

E
Etienne Basset 已提交
1602
	/* we don't log here as rc can be overriden */
1603 1604
	skp = smk_find_entry(file->f_security);
	rc = smk_access(skp, tkp->smk_known, MAY_WRITE, NULL);
C
Casey Schaufler 已提交
1605
	rc = smk_bu_note("sigiotask", skp, tkp->smk_known, MAY_WRITE, rc);
1606
	if (rc != 0 && has_capability(tsk, CAP_MAC_OVERRIDE))
E
Etienne Basset 已提交
1607 1608 1609 1610
		rc = 0;

	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
	smk_ad_setfield_u_tsk(&ad, tsk);
1611
	smack_log(file->f_security, tkp->smk_known, MAY_WRITE, rc, &ad);
1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622
	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
1623
	int rc;
1624
	int may = 0;
E
Etienne Basset 已提交
1625
	struct smk_audit_info ad;
1626

1627
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
E
Etienne Basset 已提交
1628
	smk_ad_setfield_u_fs_path(&ad, file->f_path);
1629 1630 1631 1632 1633 1634 1635 1636
	/*
	 * 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
1637 1638 1639
	rc = smk_curacc(file->f_security, may, &ad);
	rc = smk_bu_file(file, may, rc);
	return rc;
1640 1641
}

1642
/**
1643
 * smack_file_open - Smack dentry open processing
1644
 * @file: the object
1645
 * @cred: task credential
1646 1647
 *
 * Set the security blob in the file structure.
1648 1649 1650
 * 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.
1651 1652 1653
 *
 * Returns 0
 */
1654
static int smack_file_open(struct file *file, const struct cred *cred)
1655
{
1656
	struct task_smack *tsp = cred->security;
A
Al Viro 已提交
1657
	struct inode_smack *isp = file_inode(file)->i_security;
1658 1659
	struct smk_audit_info ad;
	int rc;
1660

1661 1662
	if (smack_privileged(CAP_MAC_OVERRIDE)) {
		file->f_security = isp->smk_inode;
1663
		return 0;
1664
	}
1665

1666 1667 1668
	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
1669
	rc = smk_bu_credfile(cred, file, MAY_READ, rc);
1670 1671 1672 1673
	if (rc == 0)
		file->f_security = isp->smk_inode;

	return rc;
1674 1675
}

1676 1677 1678 1679
/*
 * Task hooks
 */

1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690
/**
 * 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)
{
1691 1692 1693 1694
	struct task_smack *tsp;

	tsp = new_task_smack(NULL, NULL, gfp);
	if (tsp == NULL)
1695
		return -ENOMEM;
1696 1697 1698

	cred->security = tsp;

1699 1700 1701 1702
	return 0;
}


1703
/**
1704 1705
 * smack_cred_free - "free" task-level security credentials
 * @cred: the credentials in question
1706 1707
 *
 */
1708
static void smack_cred_free(struct cred *cred)
1709
{
1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724
	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);
1725 1726
}

D
David Howells 已提交
1727 1728 1729 1730 1731 1732 1733 1734 1735 1736 1737
/**
 * 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)
{
1738 1739
	struct task_smack *old_tsp = old->security;
	struct task_smack *new_tsp;
1740
	int rc;
1741

1742
	new_tsp = new_task_smack(old_tsp->smk_task, old_tsp->smk_task, gfp);
1743 1744 1745
	if (new_tsp == NULL)
		return -ENOMEM;

1746 1747 1748 1749
	rc = smk_copy_rules(&new_tsp->smk_rules, &old_tsp->smk_rules, gfp);
	if (rc != 0)
		return rc;

1750
	new->security = new_tsp;
D
David Howells 已提交
1751 1752 1753
	return 0;
}

1754 1755 1756 1757 1758 1759 1760 1761 1762
/**
 * 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)
{
1763 1764 1765 1766 1767
	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;
1768 1769 1770 1771 1772
	mutex_init(&new_tsp->smk_rules_lock);
	INIT_LIST_HEAD(&new_tsp->smk_rules);


	/* cbs copy rule list */
1773 1774
}

1775 1776
/**
 * smack_kernel_act_as - Set the subjective context in a set of credentials
1777 1778
 * @new: points to the set of credentials to be modified.
 * @secid: specifies the security ID to be set
1779 1780 1781 1782 1783
 *
 * Set the security data for a kernel service.
 */
static int smack_kernel_act_as(struct cred *new, u32 secid)
{
1784
	struct task_smack *new_tsp = new->security;
1785
	struct smack_known *skp = smack_from_secid(secid);
1786

1787
	if (skp == NULL)
1788 1789
		return -EINVAL;

1790
	new_tsp->smk_task = skp;
1791 1792 1793 1794 1795
	return 0;
}

/**
 * smack_kernel_create_files_as - Set the file creation label in a set of creds
1796 1797
 * @new: points to the set of credentials to be modified
 * @inode: points to the inode to use as a reference
1798 1799 1800 1801 1802 1803 1804 1805
 *
 * 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;
1806
	struct task_smack *tsp = new->security;
1807

1808 1809
	tsp->smk_forked = smk_find_entry(isp->smk_inode);
	tsp->smk_task = tsp->smk_forked;
1810 1811 1812
	return 0;
}

E
Etienne Basset 已提交
1813 1814 1815
/**
 * smk_curacc_on_task - helper to log task related access
 * @p: the task object
1816 1817
 * @access: the access requested
 * @caller: name of the calling function for audit
E
Etienne Basset 已提交
1818 1819 1820
 *
 * Return 0 if access is permitted
 */
1821 1822
static int smk_curacc_on_task(struct task_struct *p, int access,
				const char *caller)
E
Etienne Basset 已提交
1823 1824
{
	struct smk_audit_info ad;
1825
	struct smack_known *skp = smk_of_task(task_security(p));
C
Casey Schaufler 已提交
1826
	int rc;
E
Etienne Basset 已提交
1827

1828
	smk_ad_init(&ad, caller, LSM_AUDIT_DATA_TASK);
E
Etienne Basset 已提交
1829
	smk_ad_setfield_u_tsk(&ad, p);
C
Casey Schaufler 已提交
1830 1831 1832
	rc = smk_curacc(skp->smk_known, access, &ad);
	rc = smk_bu_task(p, access, rc);
	return rc;
E
Etienne Basset 已提交
1833 1834
}

1835 1836 1837 1838 1839 1840 1841 1842 1843
/**
 * 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)
{
1844
	return smk_curacc_on_task(p, MAY_WRITE, __func__);
1845 1846 1847 1848 1849 1850 1851 1852 1853 1854
}

/**
 * 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)
{
1855
	return smk_curacc_on_task(p, MAY_READ, __func__);
1856 1857 1858 1859 1860 1861 1862 1863 1864 1865
}

/**
 * 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)
{
1866
	return smk_curacc_on_task(p, MAY_READ, __func__);
1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877
}

/**
 * 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)
{
1878 1879 1880
	struct smack_known *skp = smk_of_task(task_security(p));

	*secid = skp->smk_secid;
1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891
}

/**
 * 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)
{
1892 1893 1894 1895
	int rc;

	rc = cap_task_setnice(p, nice);
	if (rc == 0)
1896
		rc = smk_curacc_on_task(p, MAY_WRITE, __func__);
1897
	return rc;
1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908
}

/**
 * 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)
{
1909 1910 1911 1912
	int rc;

	rc = cap_task_setioprio(p, ioprio);
	if (rc == 0)
1913
		rc = smk_curacc_on_task(p, MAY_WRITE, __func__);
1914
	return rc;
1915 1916 1917 1918 1919 1920 1921 1922 1923 1924
}

/**
 * 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)
{
1925
	return smk_curacc_on_task(p, MAY_READ, __func__);
1926 1927 1928 1929 1930 1931 1932 1933 1934 1935
}

/**
 * smack_task_setscheduler - Smack check on setting scheduler
 * @p: the task object
 * @policy: unused
 * @lp: unused
 *
 * Return 0 if read access is permitted
 */
1936
static int smack_task_setscheduler(struct task_struct *p)
1937
{
1938 1939
	int rc;

1940
	rc = cap_task_setscheduler(p);
1941
	if (rc == 0)
1942
		rc = smk_curacc_on_task(p, MAY_WRITE, __func__);
1943
	return rc;
1944 1945 1946 1947 1948 1949 1950 1951 1952 1953
}

/**
 * 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)
{
1954
	return smk_curacc_on_task(p, MAY_READ, __func__);
1955 1956 1957 1958 1959 1960 1961 1962 1963 1964
}

/**
 * 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)
{
1965
	return smk_curacc_on_task(p, MAY_WRITE, __func__);
1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982
}

/**
 * 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
1983
	struct smk_audit_info ad;
1984 1985
	struct smack_known *skp;
	struct smack_known *tkp = smk_of_task(task_security(p));
C
Casey Schaufler 已提交
1986
	int rc;
E
Etienne Basset 已提交
1987 1988 1989

	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
	smk_ad_setfield_u_tsk(&ad, p);
1990 1991 1992 1993
	/*
	 * Sending a signal requires that the sender
	 * can write the receiver.
	 */
C
Casey Schaufler 已提交
1994 1995 1996 1997 1998
	if (secid == 0) {
		rc = smk_curacc(tkp->smk_known, MAY_WRITE, &ad);
		rc = smk_bu_task(p, MAY_WRITE, rc);
		return rc;
	}
1999 2000 2001 2002 2003
	/*
	 * 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.
	 */
2004
	skp = smack_from_secid(secid);
C
Casey Schaufler 已提交
2005 2006 2007
	rc = smk_access(skp, tkp->smk_known, MAY_WRITE, &ad);
	rc = smk_bu_note("USB signal", skp, tkp->smk_known, MAY_WRITE, rc);
	return rc;
2008 2009 2010 2011 2012 2013
}

/**
 * smack_task_wait - Smack access check for waiting
 * @p: task to wait for
 *
2014
 * Returns 0
2015 2016 2017 2018
 */
static int smack_task_wait(struct task_struct *p)
{
	/*
2019 2020 2021 2022 2023 2024
	 * 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.
2025
	 */
2026
	return 0;
2027 2028 2029 2030 2031
}

/**
 * smack_task_to_inode - copy task smack into the inode blob
 * @p: task to copy from
2032
 * @inode: inode to copy to
2033 2034 2035 2036 2037 2038
 *
 * 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;
2039 2040 2041
	struct smack_known *skp = smk_of_task(task_security(p));

	isp->smk_inode = skp->smk_known;
2042 2043 2044 2045 2046 2047 2048 2049 2050 2051
}

/*
 * Socket hooks.
 */

/**
 * smack_sk_alloc_security - Allocate a socket blob
 * @sk: the socket
 * @family: unused
2052
 * @gfp_flags: memory allocation flags
2053 2054 2055 2056 2057 2058 2059
 *
 * 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)
{
2060
	struct smack_known *skp = smk_of_current();
2061 2062 2063 2064 2065 2066
	struct socket_smack *ssp;

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

2067
	ssp->smk_in = skp;
2068
	ssp->smk_out = skp;
2069
	ssp->smk_packet = NULL;
2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086

	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);
}

2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 2108 2109 2110 2111 2112 2113
/**
* 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.
*/
static char *smack_host_label(struct sockaddr_in *sip)
{
	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 ==
2114 2115 2116 2117
		    (siap->s_addr & (&snp->smk_mask)->s_addr)) {
			/* we have found the special CIPSO option */
			if (snp->smk_label == smack_cipso_option)
				return NULL;
2118
			return snp->smk_label;
2119
		}
2120 2121 2122 2123

	return NULL;
}

2124 2125 2126
/**
 * smack_netlabel - Set the secattr on a socket
 * @sk: the socket
2127
 * @labeled: socket label scheme
2128 2129 2130 2131 2132 2133
 *
 * Convert the outbound smack value (smk_out) to a
 * secattr and attach it to the socket.
 *
 * Returns 0 on success or an error code
 */
2134
static int smack_netlabel(struct sock *sk, int labeled)
2135
{
2136
	struct smack_known *skp;
2137
	struct socket_smack *ssp = sk->sk_security;
2138
	int rc = 0;
2139

2140 2141 2142 2143 2144 2145 2146 2147 2148 2149 2150 2151 2152 2153 2154
	/*
	 * 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 {
2155
		skp = ssp->smk_out;
2156
		rc = netlbl_sock_setattr(sk, sk->sk_family, &skp->smk_netlabel);
2157 2158 2159 2160
	}

	bh_unlock_sock(sk);
	local_bh_enable();
2161

2162 2163 2164
	return rc;
}

2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176 2177
/**
 * 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)
{
2178
	struct smack_known *skp;
2179 2180 2181 2182
	int rc;
	int sk_lbl;
	char *hostsp;
	struct socket_smack *ssp = sk->sk_security;
E
Etienne Basset 已提交
2183
	struct smk_audit_info ad;
2184 2185 2186 2187

	rcu_read_lock();
	hostsp = smack_host_label(sap);
	if (hostsp != NULL) {
E
Etienne Basset 已提交
2188
#ifdef CONFIG_AUDIT
2189 2190
		struct lsm_network_audit net;

2191 2192 2193 2194
		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
2195
#endif
2196
		sk_lbl = SMACK_UNLABELED_SOCKET;
2197 2198
		skp = ssp->smk_out;
		rc = smk_access(skp, hostsp, MAY_WRITE, &ad);
C
Casey Schaufler 已提交
2199
		rc = smk_bu_note("IPv4 host check", skp, hostsp, MAY_WRITE, rc);
2200 2201 2202 2203 2204 2205 2206 2207 2208 2209 2210
	} else {
		sk_lbl = SMACK_CIPSO_SOCKET;
		rc = 0;
	}
	rcu_read_unlock();
	if (rc != 0)
		return rc;

	return smack_netlabel(sk, sk_lbl);
}

2211 2212 2213 2214 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
/**
 * 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
 */
2291
static int smk_ipv6_port_check(struct sock *sk, struct sockaddr_in6 *address,
2292 2293 2294 2295 2296 2297
				int act)
{
	__be16 *bep;
	__be32 *be32p;
	struct smk_port_label *spp;
	struct socket_smack *ssp = sk->sk_security;
2298
	struct smack_known *skp;
2299 2300 2301
	unsigned short port = 0;
	char *object;
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
2302
	int rc;
2303 2304 2305 2306 2307
#ifdef CONFIG_AUDIT
	struct lsm_network_audit net;
#endif

	if (act == SMK_RECEIVING) {
2308
		skp = smack_net_ambient;
2309
		object = ssp->smk_in->smk_known;
2310
	} else {
2311 2312
		skp = ssp->smk_out;
		object = smack_net_ambient->smk_known;
2313 2314 2315 2316 2317
	}

	/*
	 * Get the IP address and port from the address.
	 */
2318 2319 2320
	port = ntohs(address->sin6_port);
	bep = (__be16 *)(&address->sin6_addr);
	be32p = (__be32 *)(&address->sin6_addr);
2321 2322 2323 2324 2325 2326 2327 2328 2329 2330 2331

	/*
	 * 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) {
2332
		skp = &smack_known_web;
2333 2334 2335 2336 2337 2338
		goto auditout;
	}

	list_for_each_entry(spp, &smk_ipv6_port_list, list) {
		if (spp->smk_port != port)
			continue;
2339
		object = spp->smk_in->smk_known;
2340
		if (act == SMK_CONNECTING)
2341
			ssp->smk_packet = spp->smk_out;
2342 2343 2344 2345 2346 2347 2348 2349 2350 2351
		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)
2352
		ad.a.u.net->v6info.saddr = address->sin6_addr;
2353
	else
2354
		ad.a.u.net->v6info.daddr = address->sin6_addr;
2355
#endif
C
Casey Schaufler 已提交
2356 2357 2358
	rc = smk_access(skp, object, MAY_WRITE, &ad);
	rc = smk_bu_note("IPv6 port check", skp, object, MAY_WRITE, rc);
	return rc;
2359 2360
}

2361 2362 2363 2364 2365 2366 2367 2368 2369 2370 2371 2372 2373 2374 2375
/**
 * 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)
{
2376
	struct smack_known *skp;
2377 2378 2379
	struct inode_smack *nsp = inode->i_security;
	struct socket_smack *ssp;
	struct socket *sock;
2380
	int rc = 0;
2381

2382
	if (value == NULL || size > SMK_LONGLABEL || size == 0)
P
Pankaj Kumar 已提交
2383
		return -EINVAL;
2384

2385 2386
	skp = smk_import_entry(value, size);
	if (skp == NULL)
2387 2388 2389
		return -EINVAL;

	if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
2390
		nsp->smk_inode = skp->smk_known;
2391
		nsp->smk_flags |= SMK_INODE_INSTANT;
2392 2393 2394 2395 2396 2397 2398 2399 2400
		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);
2401
	if (sock == NULL || sock->sk == NULL)
2402 2403 2404 2405 2406
		return -EOPNOTSUPP;

	ssp = sock->sk->sk_security;

	if (strcmp(name, XATTR_SMACK_IPIN) == 0)
2407
		ssp->smk_in = skp;
2408
	else if (strcmp(name, XATTR_SMACK_IPOUT) == 0) {
2409
		ssp->smk_out = skp;
2410
		if (sock->sk->sk_family == PF_INET) {
C
Casey Schaufler 已提交
2411 2412 2413 2414 2415 2416
			rc = smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET);
			if (rc != 0)
				printk(KERN_WARNING
					"Smack: \"%s\" netlbl error %d.\n",
					__func__, -rc);
		}
2417 2418 2419
	} else
		return -EOPNOTSUPP;

2420 2421 2422
	if (sock->sk->sk_family == PF_INET6)
		smk_ipv6_port_label(sock, NULL);

2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436 2437 2438 2439 2440
	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)
{
2441
	if (family != PF_INET || sock->sk == NULL)
2442 2443 2444 2445
		return 0;
	/*
	 * Set the outbound netlbl.
	 */
2446 2447 2448
	return smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET);
}

2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 2467
/**
 * 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;
}

2468 2469 2470 2471 2472 2473 2474 2475 2476 2477 2478 2479 2480
/**
 * 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)
{
2481 2482 2483
	int rc = 0;

	if (sock->sk == NULL)
2484 2485
		return 0;

2486 2487 2488 2489 2490 2491 2492 2493 2494
	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;
2495 2496
		rc = smk_ipv6_port_check(sock->sk, (struct sockaddr_in6 *)sap,
						SMK_CONNECTING);
2497 2498 2499
		break;
	}
	return rc;
2500 2501 2502 2503 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
}

/**
 * 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)
{
2530 2531 2532
	struct smack_known *skp = smk_of_current();

	msg->security = skp->smk_known;
2533 2534 2535 2536 2537 2538 2539 2540 2541 2542 2543 2544 2545 2546 2547 2548 2549 2550 2551 2552 2553 2554 2555 2556 2557 2558 2559 2560 2561 2562 2563 2564 2565 2566
	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
 */
static char *smack_of_shm(struct shmid_kernel *shp)
{
	return (char *)shp->shm_perm.security;
}

/**
 * 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;
2567
	struct smack_known *skp = smk_of_current();
2568

2569
	isp->security = skp->smk_known;
2570 2571 2572 2573 2574 2575 2576 2577 2578 2579 2580 2581 2582 2583 2584 2585
	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
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2586 2587 2588 2589 2590 2591 2592 2593 2594 2595 2596
/**
 * 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)
{
	char *ssp = smack_of_shm(shp);
	struct smk_audit_info ad;
C
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	int rc;
E
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2598 2599 2600 2601 2602

#ifdef CONFIG_AUDIT
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
	ad.a.u.ipc_id = shp->shm_perm.id;
#endif
C
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	rc = smk_curacc(ssp, access, &ad);
	rc = smk_bu_current("shm", ssp, access, rc);
	return rc;
E
Etienne Basset 已提交
2606 2607
}

2608 2609 2610 2611 2612 2613 2614 2615 2616 2617 2618 2619
/**
 * 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);
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Etienne Basset 已提交
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	return smk_curacc_shm(shp, may);
2621 2622 2623 2624 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
}

/**
 * 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
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	return smk_curacc_shm(shp, may);
2655 2656 2657 2658 2659 2660 2661 2662 2663 2664 2665 2666 2667 2668 2669 2670
}

/**
 * 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
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	return smk_curacc_shm(shp, may);
2672 2673 2674 2675 2676 2677 2678 2679 2680 2681 2682 2683 2684 2685 2686 2687 2688 2689 2690 2691 2692 2693
}

/**
 * smack_of_sem - the smack pointer for the sem
 * @sma: the object
 *
 * Returns a pointer to the smack value
 */
static char *smack_of_sem(struct sem_array *sma)
{
	return (char *)sma->sem_perm.security;
}

/**
 * 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;
2694
	struct smack_known *skp = smk_of_current();
2695

2696
	isp->security = skp->smk_known;
2697 2698 2699 2700 2701 2702 2703 2704 2705 2706 2707 2708 2709 2710 2711 2712
	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
2713 2714 2715 2716 2717 2718 2719 2720 2721 2722 2723
/**
 * 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)
{
	char *ssp = smack_of_sem(sma);
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
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	int rc;
E
Etienne Basset 已提交
2725 2726 2727 2728 2729

#ifdef CONFIG_AUDIT
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
	ad.a.u.ipc_id = sma->sem_perm.id;
#endif
C
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	rc = smk_curacc(ssp, access, &ad);
	rc = smk_bu_current("sem", ssp, access, rc);
	return rc;
E
Etienne Basset 已提交
2733 2734
}

2735 2736 2737 2738 2739 2740 2741 2742 2743 2744 2745 2746
/**
 * 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);
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Etienne Basset 已提交
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	return smk_curacc_sem(sma, may);
2748 2749 2750 2751 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
}

/**
 * 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
2787
	return smk_curacc_sem(sma, may);
2788 2789 2790 2791 2792 2793 2794 2795 2796 2797 2798 2799 2800 2801 2802 2803
}

/**
 * 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
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	return smk_curacc_sem(sma, MAY_READWRITE);
2805 2806 2807 2808 2809 2810 2811 2812 2813 2814 2815
}

/**
 * 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;
2816
	struct smack_known *skp = smk_of_current();
2817

2818
	kisp->security = skp->smk_known;
2819 2820 2821 2822 2823 2824 2825 2826 2827 2828 2829 2830 2831 2832 2833 2834 2835 2836 2837 2838 2839 2840 2841 2842 2843 2844 2845
	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
 *
 * Returns a pointer to the smack value
 */
static char *smack_of_msq(struct msg_queue *msq)
{
	return (char *)msq->q_perm.security;
}

E
Etienne Basset 已提交
2846 2847 2848 2849 2850 2851 2852 2853 2854 2855 2856
/**
 * 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)
{
	char *msp = smack_of_msq(msq);
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
2857
	int rc;
E
Etienne Basset 已提交
2858 2859 2860 2861 2862

#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
2863 2864 2865
	rc = smk_curacc(msp, access, &ad);
	rc = smk_bu_current("msq", msp, access, rc);
	return rc;
E
Etienne Basset 已提交
2866 2867
}

2868 2869 2870 2871 2872 2873 2874 2875 2876 2877 2878 2879
/**
 * 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
2880
	return smk_curacc_msq(msq, may);
2881 2882 2883 2884 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
}

/**
 * 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
2913
	return smk_curacc_msq(msq, may);
2914 2915 2916 2917 2918 2919 2920 2921 2922 2923 2924 2925 2926
}

/**
 * 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
2927
	int may;
2928

E
Etienne Basset 已提交
2929 2930
	may = smack_flags_to_may(msqflg);
	return smk_curacc_msq(msq, may);
2931 2932 2933 2934 2935 2936 2937 2938 2939 2940 2941 2942 2943 2944 2945
}

/**
 * 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
2946
	return smk_curacc_msq(msq, MAY_READWRITE);
2947 2948 2949 2950 2951 2952 2953 2954 2955 2956 2957 2958
}

/**
 * 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)
{
	char *isp = ipp->security;
E
Etienne Basset 已提交
2959 2960
	int may = smack_flags_to_may(flag);
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
2961
	int rc;
2962

E
Etienne Basset 已提交
2963 2964 2965 2966
#ifdef CONFIG_AUDIT
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
	ad.a.u.ipc_id = ipp->id;
#endif
C
Casey Schaufler 已提交
2967 2968 2969
	rc = smk_curacc(isp, may, &ad);
	rc = smk_bu_current("svipc", isp, may, rc);
	return rc;
2970 2971
}

2972 2973
/**
 * smack_ipc_getsecid - Extract smack security id
2974
 * @ipp: the object permissions
2975 2976 2977 2978 2979 2980 2981 2982 2983
 * @secid: where result will be saved
 */
static void smack_ipc_getsecid(struct kern_ipc_perm *ipp, u32 *secid)
{
	char *smack = ipp->security;

	*secid = smack_to_secid(smack);
}

2984 2985
/**
 * smack_d_instantiate - Make sure the blob is correct on an inode
2986
 * @opt_dentry: dentry where inode will be attached
2987 2988 2989 2990 2991 2992 2993 2994 2995
 * @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;
2996 2997
	struct smack_known *skp;
	struct smack_known *ckp = smk_of_current();
2998
	char *final;
2999 3000
	char trattr[TRANS_TRUE_SIZE];
	int transflag = 0;
C
Casey Schaufler 已提交
3001
	int rc;
3002 3003 3004 3005 3006 3007 3008 3009 3010 3011 3012 3013 3014 3015 3016 3017 3018 3019 3020 3021 3022 3023 3024
	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
3025 3026 3027 3028 3029 3030 3031
	/*
	 * 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) {
3032 3033 3034 3035 3036 3037 3038 3039 3040
		if (sbp->s_magic == CGROUP_SUPER_MAGIC) {
			/*
			 * The cgroup filesystem is never mounted,
			 * so there's no opportunity to set the mount
			 * options.
			 */
			sbsp->smk_root = smack_known_star.smk_known;
			sbsp->smk_default = smack_known_star.smk_known;
		}
C
Casey Schaufler 已提交
3041 3042 3043 3044 3045
		isp->smk_inode = sbsp->smk_root;
		isp->smk_flags |= SMK_INODE_INSTANT;
		goto unlockandout;
	}

3046 3047 3048 3049 3050 3051 3052 3053
	/*
	 * 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:
3054 3055 3056
	case PIPEFS_MAGIC:
	case SOCKFS_MAGIC:
	case CGROUP_SUPER_MAGIC:
3057
		/*
L
Lucas De Marchi 已提交
3058
		 * Casey says that it's a little embarrassing
3059 3060
		 * that the smack file system doesn't do
		 * extended attributes.
3061
		 *
3062
		 * Casey says pipes are easy (?)
3063 3064 3065 3066 3067
		 *
		 * Socket access is controlled by the socket
		 * structures associated with the task involved.
		 *
		 * Cgroupfs is special
3068 3069 3070 3071 3072 3073 3074 3075 3076
		 */
		final = smack_known_star.smk_known;
		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.
		 */
3077
		final = ckp->smk_known;
3078 3079 3080 3081 3082 3083 3084 3085 3086 3087 3088 3089 3090 3091 3092 3093 3094 3095 3096 3097 3098 3099 3100 3101 3102 3103
		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.
		 */
		final = smack_known_star.smk_known;
		/*
		 * 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
3104 3105 3106 3107 3108 3109 3110 3111 3112 3113
		 */

		/*
		 * UNIX domain sockets use lower level socket data.
		 */
		if (S_ISSOCK(inode->i_mode)) {
			final = smack_known_star.smk_known;
			break;
		}
		/*
3114 3115 3116 3117 3118 3119 3120 3121 3122 3123
		 * 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.
		 */
3124
		dp = dget(opt_dentry);
3125 3126 3127
		skp = smk_fetch(XATTR_NAME_SMACK, inode, dp);
		if (skp != NULL)
			final = skp->smk_known;
C
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3128 3129 3130 3131 3132 3133 3134 3135 3136 3137 3138 3139 3140 3141 3142 3143 3144

		/*
		 * 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,
3145
					XATTR_NAME_SMACKTRANSMUTE,
C
Casey Schaufler 已提交
3146 3147 3148 3149 3150 3151 3152 3153 3154
					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;
3155
			}
C
Casey Schaufler 已提交
3156 3157
			if (rc >= 0)
				transflag = SMK_INODE_TRANSMUTE;
3158
		}
3159 3160 3161 3162 3163 3164 3165 3166 3167 3168 3169
		/*
		 * 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;
3170

3171 3172 3173 3174 3175
		dput(dp);
		break;
	}

	if (final == NULL)
3176
		isp->smk_inode = ckp->smk_known;
3177 3178 3179
	else
		isp->smk_inode = final;

3180
	isp->smk_flags |= (SMK_INODE_INSTANT | transflag);
3181 3182 3183 3184 3185 3186 3187 3188 3189 3190 3191 3192 3193 3194 3195 3196 3197 3198

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)
{
3199
	struct smack_known *skp = smk_of_task(task_security(p));
3200 3201 3202 3203 3204 3205
	char *cp;
	int slen;

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

3206
	cp = kstrdup(skp->smk_known, GFP_KERNEL);
3207 3208 3209 3210 3211 3212 3213 3214 3215 3216 3217 3218 3219 3220 3221 3222 3223 3224 3225 3226 3227 3228 3229
	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)
{
3230
	struct task_smack *tsp;
D
David Howells 已提交
3231
	struct cred *new;
3232
	struct smack_known *skp;
3233 3234 3235 3236 3237 3238 3239 3240

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

3241
	if (!smack_privileged(CAP_MAC_ADMIN))
3242 3243
		return -EPERM;

3244
	if (value == NULL || size == 0 || size >= SMK_LONGLABEL)
3245 3246 3247 3248 3249
		return -EINVAL;

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

3250 3251
	skp = smk_import_entry(value, size);
	if (skp == NULL)
3252 3253
		return -EINVAL;

3254 3255 3256
	/*
	 * No process is ever allowed the web ("@") label.
	 */
3257
	if (skp == &smack_known_web)
3258 3259
		return -EPERM;

D
David Howells 已提交
3260
	new = prepare_creds();
3261
	if (new == NULL)
D
David Howells 已提交
3262
		return -ENOMEM;
3263

3264
	tsp = new->security;
3265
	tsp->smk_task = skp;
3266

D
David Howells 已提交
3267
	commit_creds(new);
3268 3269 3270 3271 3272
	return size;
}

/**
 * smack_unix_stream_connect - Smack access on UDS
3273 3274
 * @sock: one sock
 * @other: the other sock
3275 3276 3277 3278 3279
 * @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
 */
3280 3281
static int smack_unix_stream_connect(struct sock *sock,
				     struct sock *other, struct sock *newsk)
3282
{
3283
	struct smack_known *skp;
3284
	struct smack_known *okp;
J
James Morris 已提交
3285 3286
	struct socket_smack *ssp = sock->sk_security;
	struct socket_smack *osp = other->sk_security;
3287
	struct socket_smack *nsp = newsk->sk_security;
E
Etienne Basset 已提交
3288
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
3289
	int rc = 0;
3290 3291 3292
#ifdef CONFIG_AUDIT
	struct lsm_network_audit net;
#endif
C
Casey Schaufler 已提交
3293

3294 3295
	if (!smack_privileged(CAP_MAC_OVERRIDE)) {
		skp = ssp->smk_out;
3296 3297 3298 3299 3300 3301
		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
		rc = smk_access(skp, okp->smk_known, MAY_WRITE, &ad);
C
Casey Schaufler 已提交
3302 3303 3304
		rc = smk_bu_note("UDS connect", skp, okp->smk_known,
					MAY_WRITE, rc);
		if (rc == 0) {
3305 3306
			rc = smk_access(okp, skp->smk_known, MAY_WRITE, NULL);
			rc = smk_bu_note("UDS connect", okp, skp->smk_known,
C
Casey Schaufler 已提交
3307 3308
						MAY_WRITE, rc);
		}
3309
	}
C
Casey Schaufler 已提交
3310

3311 3312 3313 3314
	/*
	 * Cross reference the peer labels for SO_PEERSEC.
	 */
	if (rc == 0) {
3315 3316
		nsp->smk_packet = ssp->smk_out;
		ssp->smk_packet = osp->smk_out;
3317 3318
	}

C
Casey Schaufler 已提交
3319
	return rc;
3320 3321 3322 3323 3324 3325 3326 3327 3328 3329 3330 3331
}

/**
 * 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
3332 3333
	struct socket_smack *ssp = sock->sk->sk_security;
	struct socket_smack *osp = other->sk->sk_security;
3334
	struct smack_known *skp;
E
Etienne Basset 已提交
3335
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
3336
	int rc;
3337

3338 3339 3340
#ifdef CONFIG_AUDIT
	struct lsm_network_audit net;

3341
	smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
E
Etienne Basset 已提交
3342
	smk_ad_setfield_u_net_sk(&ad, other->sk);
3343
#endif
C
Casey Schaufler 已提交
3344

3345 3346
	if (smack_privileged(CAP_MAC_OVERRIDE))
		return 0;
C
Casey Schaufler 已提交
3347

3348
	skp = ssp->smk_out;
C
Casey Schaufler 已提交
3349 3350 3351 3352
	rc = smk_access(skp, osp->smk_in->smk_known, MAY_WRITE, &ad);
	rc = smk_bu_note("UDS send", skp, osp->smk_in->smk_known,
				MAY_WRITE, rc);
	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
		rc = smk_access(skp, ssp->smk_in->smk_known, MAY_WRITE, &ad);
C
Casey Schaufler 已提交
3567 3568
		rc = smk_bu_note("IPv4 delivery", skp, ssp->smk_in->smk_known,
					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
	char *hsp;
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
	rc = smk_access(skp, ssp->smk_in->smk_known, MAY_WRITE, &ad);
C
Casey Schaufler 已提交
3749 3750
	rc = smk_bu_note("IPv4 connect", skp, ssp->smk_in->smk_known,
				MAY_WRITE, rc);
3751 3752 3753 3754 3755 3756 3757
	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.
	 */
3758
	req->peer_secid = skp->smk_secid;
3759 3760 3761 3762

	/*
	 * 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
3763
	 * propagate the wire-label to the sock when it is created.
3764 3765 3766 3767
	 */
	hdr = ip_hdr(skb);
	addr.sin_addr.s_addr = hdr->saddr;
	rcu_read_lock();
3768 3769 3770
	hsp = smack_host_label(&addr);
	rcu_read_unlock();

3771
	if (hsp == NULL)
3772
		rc = netlbl_req_setattr(req, &skp->smk_netlabel);
3773
	else
3774
		netlbl_req_delattr(req);
3775 3776 3777 3778

	return rc;
}

3779 3780 3781 3782 3783 3784 3785 3786 3787 3788 3789
/**
 * 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;
3790
	struct smack_known *skp;
3791

3792 3793
	if (req->peer_secid != 0) {
		skp = smack_from_secid(req->peer_secid);
3794
		ssp->smk_packet = skp;
3795
	} else
3796
		ssp->smk_packet = NULL;
3797 3798
}

3799 3800 3801 3802 3803 3804 3805 3806 3807 3808 3809 3810
/*
 * 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
3811
 * @cred: the credentials to use
3812 3813 3814 3815 3816 3817
 * @flags: unused
 *
 * No allocation required
 *
 * Returns 0
 */
D
David Howells 已提交
3818
static int smack_key_alloc(struct key *key, const struct cred *cred,
3819 3820
			   unsigned long flags)
{
3821 3822 3823
	struct smack_known *skp = smk_of_task(cred->security);

	key->security = skp->smk_known;
3824 3825 3826 3827 3828 3829 3830 3831 3832 3833 3834 3835 3836 3837 3838 3839 3840
	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
3841
 * @cred: the credentials to use
3842 3843 3844 3845 3846 3847
 * @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,
3848
				const struct cred *cred, unsigned perm)
3849 3850
{
	struct key *keyp;
E
Etienne Basset 已提交
3851
	struct smk_audit_info ad;
3852
	struct smack_known *tkp = smk_of_task(cred->security);
3853
	int request = 0;
C
Casey Schaufler 已提交
3854
	int rc;
3855 3856 3857 3858 3859 3860 3861 3862 3863 3864 3865 3866 3867

	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
	 */
3868
	if (tkp == NULL)
3869
		return -EACCES;
E
Etienne Basset 已提交
3870 3871 3872 3873 3874
#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
3875 3876 3877 3878
	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
3879 3880 3881
	rc = smk_access(tkp, keyp->security, request, &ad);
	rc = smk_bu_note("key access", tkp, keyp->security, request, rc);
	return rc;
3882 3883 3884
}
#endif /* CONFIG_KEYS */

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 3911 3912 3913 3914 3915 3916 3917
/*
 * 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)
{
	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 3921 3922 3923 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
		return -EINVAL;

	*rule = smk_import(rulestr, 0);

	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)
{
3963
	struct smack_known *skp;
3964 3965
	char *rule = vrule;

3966 3967
	if (unlikely(!rule)) {
		WARN_ONCE(1, "Smack: missing rule\n");
3968 3969 3970 3971 3972 3973
		return -ENOENT;
	}

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

3974
	skp = smack_from_secid(secid);
3975 3976 3977 3978 3979 3980

	/*
	 * No need to do string comparisons. If a match occurs,
	 * both pointers will point to the same smack_known
	 * label.
	 */
3981
	if (op == Audit_equal)
3982
		return (rule == skp->smk_known);
3983
	if (op == Audit_not_equal)
3984
		return (rule != skp->smk_known);
3985 3986 3987 3988 3989 3990 3991 3992 3993 3994 3995 3996 3997 3998 3999 4000 4001

	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 */

4002 4003 4004 4005 4006 4007 4008 4009 4010 4011
/**
 * 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);
}


4012
/**
4013 4014 4015 4016 4017 4018 4019 4020 4021
 * 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)
{
4022
	struct smack_known *skp = smack_from_secid(secid);
4023

4024
	if (secdata)
4025 4026
		*secdata = skp->smk_known;
	*seclen = strlen(skp->smk_known);
4027 4028 4029
	return 0;
}

4030
/**
4031 4032 4033 4034 4035 4036 4037
 * 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.
 */
4038
static int smack_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
4039 4040 4041 4042 4043
{
	*secid = smack_to_secid(secdata);
	return 0;
}

4044
/**
4045
 * smack_release_secctx - don't do anything.
4046 4047
 * @secdata: unused
 * @seclen: unused
4048 4049 4050 4051 4052 4053 4054
 *
 * Exists to make sure nothing gets done, and properly
 */
static void smack_release_secctx(char *secdata, u32 seclen)
{
}

4055 4056 4057 4058 4059 4060 4061 4062 4063 4064 4065 4066 4067 4068 4069 4070 4071 4072 4073 4074 4075
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;
}

4076 4077 4078
struct security_operations smack_ops = {
	.name =				"smack",

4079
	.ptrace_access_check =		smack_ptrace_access_check,
4080
	.ptrace_traceme =		smack_ptrace_traceme,
4081 4082 4083 4084 4085 4086 4087 4088
	.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,

4089
	.bprm_set_creds =		smack_bprm_set_creds,
4090 4091
	.bprm_committing_creds =	smack_bprm_committing_creds,
	.bprm_secureexec =		smack_bprm_secureexec,
4092

4093 4094 4095 4096 4097 4098 4099 4100 4101 4102 4103 4104 4105 4106 4107 4108 4109
	.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,
4110
	.inode_getsecid =		smack_inode_getsecid,
4111 4112 4113 4114 4115 4116 4117

	.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,
4118 4119
	.mmap_file =			smack_mmap_file,
	.mmap_addr =			cap_mmap_addr,
4120 4121 4122 4123
	.file_set_fowner = 		smack_file_set_fowner,
	.file_send_sigiotask = 		smack_file_send_sigiotask,
	.file_receive = 		smack_file_receive,

4124
	.file_open =			smack_file_open,
4125

4126
	.cred_alloc_blank =		smack_cred_alloc_blank,
4127
	.cred_free =			smack_cred_free,
D
David Howells 已提交
4128
	.cred_prepare =			smack_cred_prepare,
4129
	.cred_transfer =		smack_cred_transfer,
4130 4131
	.kernel_act_as =		smack_kernel_act_as,
	.kernel_create_files_as =	smack_kernel_create_files_as,
4132 4133 4134 4135 4136 4137 4138 4139 4140 4141 4142 4143 4144 4145 4146
	.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,
4147
	.ipc_getsecid =			smack_ipc_getsecid,
4148 4149 4150 4151 4152 4153 4154 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

	.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,
4180
	.socket_bind =			smack_socket_bind,
4181 4182
	.socket_connect =		smack_socket_connect,
	.socket_sendmsg =		smack_socket_sendmsg,
4183 4184 4185 4186 4187 4188 4189
	.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,
4190
	.inet_csk_clone =		smack_inet_csk_clone,
4191

4192 4193 4194 4195 4196 4197
 /* 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 */
4198 4199 4200 4201 4202 4203 4204 4205 4206

 /* 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 */

4207
	.ismaclabel =			smack_ismaclabel,
4208
	.secid_to_secctx = 		smack_secid_to_secctx,
4209
	.secctx_to_secid = 		smack_secctx_to_secid,
4210
	.release_secctx = 		smack_release_secctx,
4211 4212 4213
	.inode_notifysecctx =		smack_inode_notifysecctx,
	.inode_setsecctx =		smack_inode_setsecctx,
	.inode_getsecctx =		smack_inode_getsecctx,
4214 4215
};

4216

4217
static __init void init_smack_known_list(void)
4218
{
4219 4220 4221 4222 4223 4224 4225 4226 4227 4228 4229 4230 4231 4232 4233 4234 4235 4236 4237 4238 4239
	/*
	 * 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
	 */
4240 4241 4242 4243 4244 4245
	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);
4246 4247
}

4248 4249 4250 4251 4252 4253 4254
/**
 * smack_init - initialize the smack system
 *
 * Returns 0
 */
static __init int smack_init(void)
{
D
David Howells 已提交
4255
	struct cred *cred;
4256
	struct task_smack *tsp;
D
David Howells 已提交
4257

4258 4259 4260
	if (!security_module_enable(&smack_ops))
		return 0;

4261 4262
	tsp = new_task_smack(&smack_known_floor, &smack_known_floor,
				GFP_KERNEL);
4263 4264 4265
	if (tsp == NULL)
		return -ENOMEM;

4266 4267 4268 4269 4270
	printk(KERN_INFO "Smack:  Initializing.\n");

	/*
	 * Set the security state for the initial task.
	 */
D
David Howells 已提交
4271
	cred = (struct cred *) current->cred;
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	cred->security = tsp;
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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);