smack_lsm.c 87.6 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/slab.h>
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#include <linux/mutex.h>
#include <linux/pipe_fs_i.h>
#include <net/netlabel.h>
#include <net/cipso_ipv4.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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/**
 * 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 char *smk_fetch(const char *name, struct inode *ip, struct dentry *dp)
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{
	int rc;
	char in[SMK_LABELLEN];

	if (ip->i_op->getxattr == NULL)
		return NULL;

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	rc = ip->i_op->getxattr(dp, name, in, SMK_LABELLEN);
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	if (rc < 0)
		return NULL;

	return smk_import(in, rc);
}

/**
 * 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;

	isp = kzalloc(sizeof(struct inode_smack), GFP_KERNEL);
	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
 */
static struct task_smack *new_task_smack(char *task, char *forked, gfp_t gfp)
{
	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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/*
 * 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
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 *
 * Returns 0 if access is OK, an error code otherwise
 *
 * Do the capability checks, and require read and write.
 */
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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 smk_audit_info ad;
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	char *tsp;
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	rc = cap_ptrace_access_check(ctp, mode);
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	if (rc != 0)
		return rc;

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	tsp = smk_of_task(task_security(ctp));
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	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
	smk_ad_setfield_u_tsk(&ad, ctp);

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	rc = smk_curacc(tsp, MAY_READWRITE, &ad);
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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
 *
 * Do the capability checks, and require read and write.
 */
static int smack_ptrace_traceme(struct task_struct *ptp)
{
	int rc;
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	struct smk_audit_info ad;
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	char *tsp;
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	rc = cap_ptrace_traceme(ptp);
	if (rc != 0)
		return rc;
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	tsp = smk_of_task(task_security(ptp));
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	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
	smk_ad_setfield_u_tsk(&ad, ptp);

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	rc = smk_curacc(tsp, MAY_READWRITE, &ad);
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	return rc;
}

/**
 * smack_syslog - Smack approval on syslog
 * @type: message type
 *
 * Require that the task has the floor label
 *
 * 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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	char *sp = smk_of_current();
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	if (capable(CAP_MAC_OVERRIDE))
		return 0;

	 if (sp != smack_known_floor.smk_known)
		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;
	sbsp->smk_initialized = 0;
	spin_lock_init(&sbsp->smk_sblock);

	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;
		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;
	char *op;
	char *commap;
	char *nsp;

	spin_lock(&sp->smk_sblock);
	if (sp->smk_initialized != 0) {
		spin_unlock(&sp->smk_sblock);
		return 0;
	}
	sp->smk_initialized = 1;
	spin_unlock(&sp->smk_sblock);

	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);
			if (nsp != NULL)
				sp->smk_hat = nsp;
		} else if (strncmp(op, SMK_FSFLOOR, strlen(SMK_FSFLOOR)) == 0) {
			op += strlen(SMK_FSFLOOR);
			nsp = smk_import(op, 0);
			if (nsp != NULL)
				sp->smk_floor = nsp;
		} else if (strncmp(op, SMK_FSDEFAULT,
				   strlen(SMK_FSDEFAULT)) == 0) {
			op += strlen(SMK_FSDEFAULT);
			nsp = smk_import(op, 0);
			if (nsp != NULL)
				sp->smk_default = nsp;
		} else if (strncmp(op, SMK_FSROOT, strlen(SMK_FSROOT)) == 0) {
			op += strlen(SMK_FSROOT);
			nsp = smk_import(op, 0);
			if (nsp != NULL)
				sp->smk_root = nsp;
		}
	}

	/*
	 * Initialize the root inode.
	 */
	isp = inode->i_security;
	if (isp == NULL)
		inode->i_security = new_inode_smack(sp->smk_root);
	else
		isp->smk_inode = sp->smk_root;

	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);
	return rc;
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}

/**
 * smack_sb_mount - Smack check for mounting
 * @dev_name: unused
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 * @path: mount point
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 * @type: unused
 * @flags: unused
 * @data: unused
 *
 * Returns 0 if current can write the floor of the filesystem
 * being mounted on, an error code otherwise.
 */
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static int smack_sb_mount(char *dev_name, struct path *path,
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			  char *type, unsigned long flags, void *data)
{
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	struct superblock_smack *sbp = path->dentry->d_sb->s_security;
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	struct smk_audit_info ad;
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	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
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	smk_ad_setfield_u_fs_path(&ad, *path);

	return smk_curacc(sbp->smk_floor, MAY_WRITE, &ad);
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}

/**
 * smack_sb_umount - Smack check for unmounting
 * @mnt: file system to unmount
 * @flags: unused
 *
 * Returns 0 if current can write the floor of the filesystem
 * being unmounted, an error code otherwise.
 */
static int smack_sb_umount(struct vfsmount *mnt, int flags)
{
	struct superblock_smack *sbp;
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	struct smk_audit_info ad;
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	struct path path;
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	path.dentry = mnt->mnt_root;
	path.mnt = mnt;
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	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
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	smk_ad_setfield_u_fs_path(&ad, path);
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	sbp = path.dentry->d_sb->s_security;
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	return smk_curacc(sbp->smk_floor, MAY_WRITE, &ad);
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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
 *
 * Returns 0 if it gets a blob, -ENOMEM otherwise
 */
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static int smack_bprm_set_creds(struct linux_binprm *bprm)
{
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	struct inode *inode = bprm->file->f_path.dentry->d_inode;
	struct task_smack *bsp = bprm->cred->security;
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	struct inode_smack *isp;
	int rc;

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

	if (bprm->cred_prepared)
		return 0;

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

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	if (bprm->unsafe)
		return -EPERM;
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	bsp->smk_task = isp->smk_task;
	bprm->per_clear |= PER_CLEAR_ON_SETID;
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	return 0;
}
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/**
 * 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;
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	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;
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}

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/*
 * Inode hooks
 */

/**
 * smack_inode_alloc_security - allocate an inode blob
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 * @inode: the inode in need of a blob
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 *
 * Returns 0 if it gets a blob, -ENOMEM otherwise
 */
static int smack_inode_alloc_security(struct inode *inode)
{
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	inode->i_security = new_inode_smack(smk_of_current());
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	if (inode->i_security == NULL)
		return -ENOMEM;
	return 0;
}

/**
 * smack_inode_free_security - free an inode blob
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 * @inode: the inode with a blob
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 *
 * 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
 * @inode: the inode
 * @dir: unused
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 * @qstr: unused
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 * @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,
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				     const struct qstr *qstr, char **name,
				     void **value, size_t *len)
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{
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	struct smack_known *skp;
	char *csp = smk_of_current();
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	char *isp = smk_of_inode(inode);
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	char *dsp = smk_of_inode(dir);
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	int may;
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	if (name) {
		*name = kstrdup(XATTR_SMACK_SUFFIX, GFP_KERNEL);
		if (*name == NULL)
			return -ENOMEM;
	}

	if (value) {
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		skp = smk_find_entry(csp);
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		rcu_read_lock();
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		may = smk_access_entry(csp, dsp, &skp->smk_rules);
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		rcu_read_unlock();
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		/*
		 * If the access rule allows transmutation and
		 * the directory requests transmutation then
		 * by all means transmute.
		 */
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		if (may > 0 && ((may & MAY_TRANSMUTE) != 0) &&
		    smk_inode_transmutable(dir))
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			isp = dsp;

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		*value = kstrdup(isp, GFP_KERNEL);
		if (*value == NULL)
			return -ENOMEM;
	}

	if (len)
		*len = strlen(isp) + 1;

	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;
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	struct smk_audit_info ad;
	int rc;

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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, old_dentry);
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	isp = smk_of_inode(old_dentry->d_inode);
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	rc = smk_curacc(isp, MAY_WRITE, &ad);
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	if (rc == 0 && new_dentry->d_inode != NULL) {
		isp = smk_of_inode(new_dentry->d_inode);
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		smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
		rc = smk_curacc(isp, MAY_WRITE, &ad);
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	}

	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;
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	struct smk_audit_info ad;
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	int rc;

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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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	/*
	 * You need write access to the thing you're unlinking
	 */
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	rc = smk_curacc(smk_of_inode(ip), MAY_WRITE, &ad);
	if (rc == 0) {
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		/*
		 * You also need write access to the containing directory
		 */
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		smk_ad_setfield_u_fs_path_dentry(&ad, NULL);
		smk_ad_setfield_u_fs_inode(&ad, dir);
		rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad);
	}
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	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)
{
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	struct smk_audit_info ad;
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	int rc;

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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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	/*
	 * You need write access to the thing you're removing
	 */
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	rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
	if (rc == 0) {
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		/*
		 * You also need write access to the containing directory
		 */
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		smk_ad_setfield_u_fs_path_dentry(&ad, NULL);
		smk_ad_setfield_u_fs_inode(&ad, dir);
		rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad);
	}
686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708

	return rc;
}

/**
 * smack_inode_rename - Smack check on rename
 * @old_inode: the old directory
 * @old_dentry: unused
 * @new_inode: the new directory
 * @new_dentry: unused
 *
 * 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;
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	struct smk_audit_info ad;

711
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
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	smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
713 714

	isp = smk_of_inode(old_dentry->d_inode);
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	rc = smk_curacc(isp, MAY_READWRITE, &ad);
716 717 718

	if (rc == 0 && new_dentry->d_inode != NULL) {
		isp = smk_of_inode(new_dentry->d_inode);
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		smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
		rc = smk_curacc(isp, MAY_READWRITE, &ad);
721 722 723 724 725 726 727 728 729 730 731 732 733
	}
	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
 */
734
static int smack_inode_permission(struct inode *inode, int mask)
735
{
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	struct smk_audit_info ad;
737
	int no_block = mask & MAY_NOT_BLOCK;
738 739

	mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
740 741 742 743 744
	/*
	 * No permission to check. Existence test. Yup, it's there.
	 */
	if (mask == 0)
		return 0;
745 746

	/* May be droppable after audit */
747
	if (no_block)
748
		return -ECHILD;
749
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
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	smk_ad_setfield_u_fs_inode(&ad, inode);
	return smk_curacc(smk_of_inode(inode), mask, &ad);
752 753 754 755 756 757 758 759 760 761 762
}

/**
 * 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)
{
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	struct smk_audit_info ad;
764 765 766 767 768
	/*
	 * Need to allow for clearing the setuid bit.
	 */
	if (iattr->ia_valid & ATTR_FORCE)
		return 0;
769
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
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	smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
771

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	return smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
773 774 775 776 777 778 779 780 781 782 783
}

/**
 * smack_inode_getattr - Smack check for getting attributes
 * @mnt: unused
 * @dentry: the object
 *
 * Returns 0 if access is permitted, an error code otherwise
 */
static int smack_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
{
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	struct smk_audit_info ad;
785
	struct path path;
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787 788
	path.dentry = dentry;
	path.mnt = mnt;
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790
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
791
	smk_ad_setfield_u_fs_path(&ad, path);
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	return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ, &ad);
793 794 795 796 797 798 799 800 801 802 803 804 805 806
}

/**
 * smack_inode_setxattr - Smack check for setting xattrs
 * @dentry: the object
 * @name: name of the attribute
 * @value: unused
 * @size: unused
 * @flags: unused
 *
 * This protects the Smack attribute explicitly.
 *
 * Returns 0 if access is permitted, an error code otherwise
 */
807 808
static int smack_inode_setxattr(struct dentry *dentry, const char *name,
				const void *value, size_t size, int flags)
809
{
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	struct smk_audit_info ad;
811
	int rc = 0;
812

813 814
	if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
	    strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
815
	    strcmp(name, XATTR_NAME_SMACKIPOUT) == 0 ||
816 817
	    strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
	    strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
818 819
		if (!capable(CAP_MAC_ADMIN))
			rc = -EPERM;
820 821 822 823 824 825
		/*
		 * check label validity here so import wont fail on
		 * post_setxattr
		 */
		if (size == 0 || size >= SMK_LABELLEN ||
		    smk_import(value, size) == NULL)
826
			rc = -EINVAL;
827 828 829 830 831 832
	} else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) {
		if (!capable(CAP_MAC_ADMIN))
			rc = -EPERM;
		if (size != TRANS_TRUE_SIZE ||
		    strncmp(value, TRANS_TRUE, TRANS_TRUE_SIZE) != 0)
			rc = -EINVAL;
833 834 835
	} else
		rc = cap_inode_setxattr(dentry, name, value, size, flags);

836
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
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837 838
	smk_ad_setfield_u_fs_path_dentry(&ad, dentry);

839
	if (rc == 0)
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840
		rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
841 842

	return rc;
843 844 845 846 847 848 849 850 851 852 853 854 855
}

/**
 * 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.
 */
856 857
static void smack_inode_post_setxattr(struct dentry *dentry, const char *name,
				      const void *value, size_t size, int flags)
858 859
{
	char *nsp;
860
	struct inode_smack *isp = dentry->d_inode->i_security;
861 862

	if (strcmp(name, XATTR_NAME_SMACK) == 0) {
863
		nsp = smk_import(value, size);
864 865 866 867
		if (nsp != NULL)
			isp->smk_inode = nsp;
		else
			isp->smk_inode = smack_known_invalid.smk_known;
868 869
	} else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0) {
		nsp = smk_import(value, size);
870 871 872 873
		if (nsp != NULL)
			isp->smk_task = nsp;
		else
			isp->smk_task = smack_known_invalid.smk_known;
874 875 876 877 878 879
	} else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
		nsp = smk_import(value, size);
		if (nsp != NULL)
			isp->smk_mmap = nsp;
		else
			isp->smk_mmap = smack_known_invalid.smk_known;
880 881
	} else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0)
		isp->smk_flags |= SMK_INODE_TRANSMUTE;
882 883 884 885

	return;
}

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/**
887 888 889 890 891 892
 * smack_inode_getxattr - Smack check on getxattr
 * @dentry: the object
 * @name: unused
 *
 * Returns 0 if access is permitted, an error code otherwise
 */
893
static int smack_inode_getxattr(struct dentry *dentry, const char *name)
894
{
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	struct smk_audit_info ad;

897
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
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	smk_ad_setfield_u_fs_path_dentry(&ad, dentry);

	return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ, &ad);
901 902
}

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903
/**
904 905 906 907 908 909 910 911
 * 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
 */
912
static int smack_inode_removexattr(struct dentry *dentry, const char *name)
913
{
914
	struct inode_smack *isp;
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	struct smk_audit_info ad;
916
	int rc = 0;
917

918 919
	if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
	    strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
920
	    strcmp(name, XATTR_NAME_SMACKIPOUT) == 0 ||
921
	    strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
922 923
	    strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0 ||
	    strcmp(name, XATTR_NAME_SMACKMMAP)) {
924 925 926 927 928
		if (!capable(CAP_MAC_ADMIN))
			rc = -EPERM;
	} else
		rc = cap_inode_removexattr(dentry, name);

929
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
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	smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
931
	if (rc == 0)
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		rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
933

934 935 936
	if (rc == 0) {
		isp = dentry->d_inode->i_security;
		isp->smk_task = NULL;
937
		isp->smk_mmap = NULL;
938 939
	}

940
	return rc;
941 942 943 944 945 946 947
}

/**
 * smack_inode_getsecurity - get smack xattrs
 * @inode: the object
 * @name: attribute name
 * @buffer: where to put the result
948
 * @alloc: unused
949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978
 *
 * 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);
		ilen = strlen(isp) + 1;
		*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);
979
	if (sock == NULL || sock->sk == NULL)
980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020
		return -EOPNOTSUPP;

	ssp = sock->sk->sk_security;

	if (strcmp(name, XATTR_SMACK_IPIN) == 0)
		isp = ssp->smk_in;
	else if (strcmp(name, XATTR_SMACK_IPOUT) == 0)
		isp = ssp->smk_out;
	else
		return -EOPNOTSUPP;

	ilen = strlen(isp) + 1;
	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)
{
	int len = strlen(XATTR_NAME_SMACK);

	if (buffer != NULL && len <= buffer_size) {
		memcpy(buffer, XATTR_NAME_SMACK, len);
		return len;
	}
	return -EINVAL;
}

1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032
/**
 * 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);
}

1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066
/*
 * 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)
{
1067
	file->f_security = smk_of_current();
1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096
	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;
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1097 1098
	struct smk_audit_info ad;

1099
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
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1100
	smk_ad_setfield_u_fs_path(&ad, file->f_path);
1101 1102

	if (_IOC_DIR(cmd) & _IOC_WRITE)
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1103
		rc = smk_curacc(file->f_security, MAY_WRITE, &ad);
1104 1105

	if (rc == 0 && (_IOC_DIR(cmd) & _IOC_READ))
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Etienne Basset 已提交
1106
		rc = smk_curacc(file->f_security, MAY_READ, &ad);
1107 1108 1109 1110 1111 1112 1113

	return rc;
}

/**
 * smack_file_lock - Smack check on file locking
 * @file: the object
1114
 * @cmd: unused
1115 1116 1117 1118 1119
 *
 * Returns 0 if current has write access, error code otherwise
 */
static int smack_file_lock(struct file *file, unsigned int cmd)
{
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1120 1121
	struct smk_audit_info ad;

1122 1123
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
	smk_ad_setfield_u_fs_path(&ad, file->f_path);
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	return smk_curacc(file->f_security, MAY_WRITE, &ad);
1125 1126 1127 1128 1129 1130 1131 1132
}

/**
 * smack_file_fcntl - Smack check on fcntl
 * @file: the object
 * @cmd: what action to check
 * @arg: unused
 *
1133 1134 1135 1136
 * Generally these operations are harmless.
 * File locking operations present an obvious mechanism
 * for passing information, so they require write access.
 *
1137 1138 1139 1140 1141
 * Returns 0 if current has access, error code otherwise
 */
static int smack_file_fcntl(struct file *file, unsigned int cmd,
			    unsigned long arg)
{
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1142
	struct smk_audit_info ad;
1143
	int rc = 0;
1144

E
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1145

1146 1147 1148 1149 1150 1151
	switch (cmd) {
	case F_GETLK:
	case F_SETLK:
	case F_SETLKW:
	case F_SETOWN:
	case F_SETSIG:
1152 1153
		smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
		smk_ad_setfield_u_fs_path(&ad, file->f_path);
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Etienne Basset 已提交
1154
		rc = smk_curacc(file->f_security, MAY_WRITE, &ad);
1155 1156
		break;
	default:
1157
		break;
1158 1159 1160 1161 1162
	}

	return rc;
}

1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177
/**
 * smack_file_mmap :
 * 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.
 */
static int smack_file_mmap(struct file *file,
			   unsigned long reqprot, unsigned long prot,
			   unsigned long flags, unsigned long addr,
			   unsigned long addr_only)
{
1178
	struct smack_known *skp;
1179 1180 1181 1182
	struct smack_rule *srp;
	struct task_smack *tsp;
	char *sp;
	char *msmack;
1183
	char *osmack;
1184 1185
	struct inode_smack *isp;
	struct dentry *dp;
1186 1187 1188
	int may;
	int mmay;
	int tmay;
1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210
	int rc;

	/* do DAC check on address space usage */
	rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
	if (rc || addr_only)
		return rc;

	if (file == NULL || file->f_dentry == NULL)
		return 0;

	dp = file->f_dentry;

	if (dp->d_inode == NULL)
		return 0;

	isp = dp->d_inode->i_security;
	if (isp->smk_mmap == NULL)
		return 0;
	msmack = isp->smk_mmap;

	tsp = current_security();
	sp = smk_of_current();
1211
	skp = smk_find_entry(sp);
1212 1213 1214 1215 1216 1217 1218 1219
	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.
	 */
1220
	list_for_each_entry_rcu(srp, &skp->smk_rules, list) {
1221
		osmack = srp->smk_object;
1222 1223 1224
		/*
		 * Matching labels always allows access.
		 */
1225
		if (msmack == osmack)
1226
			continue;
1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248
		/*
		 * If there is a matching local rule take
		 * that into account as well.
		 */
		may = smk_access_entry(srp->smk_subject, osmack,
					&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.
		 */
1249 1250
		skp = smk_find_entry(msmack);
		mmay = smk_access_entry(msmack, osmack, &skp->smk_rules);
1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261
		if (mmay == -ENOENT) {
			rc = -EACCES;
			break;
		}
		/*
		 * If there is a local entry it modifies the
		 * potential access, too.
		 */
		tmay = smk_access_entry(msmack, osmack, &tsp->smk_rules);
		if (tmay != -ENOENT)
			mmay &= tmay;
1262

1263 1264 1265 1266 1267
		/*
		 * If there is any access available to current that is
		 * not available to a SMACK64MMAP subject
		 * deny access.
		 */
1268
		if ((may | mmay) != mmay) {
1269
			rc = -EACCES;
1270
			break;
1271
		}
1272 1273 1274 1275 1276 1277 1278
	}

	rcu_read_unlock();

	return rc;
}

1279 1280 1281 1282 1283 1284 1285 1286 1287
/**
 * 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)
{
1288
	file->f_security = smk_of_current();
1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307
	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)
{
	struct file *file;
	int rc;
1308
	char *tsp = smk_of_task(tsk->cred->security);
E
Etienne Basset 已提交
1309
	struct smk_audit_info ad;
1310 1311 1312 1313 1314

	/*
	 * struct fown_struct is never outside the context of a struct file
	 */
	file = container_of(fown, struct file, f_owner);
1315

E
Etienne Basset 已提交
1316 1317
	/* we don't log here as rc can be overriden */
	rc = smk_access(file->f_security, tsp, MAY_WRITE, NULL);
1318
	if (rc != 0 && has_capability(tsk, CAP_MAC_OVERRIDE))
E
Etienne Basset 已提交
1319 1320 1321 1322 1323
		rc = 0;

	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
	smk_ad_setfield_u_tsk(&ad, tsk);
	smack_log(file->f_security, tsp, MAY_WRITE, rc, &ad);
1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335
	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)
{
	int may = 0;
E
Etienne Basset 已提交
1336
	struct smk_audit_info ad;
1337

E
Etienne Basset 已提交
1338 1339
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
	smk_ad_setfield_u_fs_path(&ad, file->f_path);
1340 1341 1342 1343 1344 1345 1346 1347
	/*
	 * This code relies on bitmasks.
	 */
	if (file->f_mode & FMODE_READ)
		may = MAY_READ;
	if (file->f_mode & FMODE_WRITE)
		may |= MAY_WRITE;

E
Etienne Basset 已提交
1348
	return smk_curacc(file->f_security, may, &ad);
1349 1350
}

1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368
/**
 * smack_dentry_open - Smack dentry open processing
 * @file: the object
 * @cred: unused
 *
 * Set the security blob in the file structure.
 *
 * Returns 0
 */
static int smack_dentry_open(struct file *file, const struct cred *cred)
{
	struct inode_smack *isp = file->f_path.dentry->d_inode->i_security;

	file->f_security = isp->smk_inode;

	return 0;
}

1369 1370 1371 1372
/*
 * Task hooks
 */

1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383
/**
 * 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)
{
1384 1385 1386 1387
	struct task_smack *tsp;

	tsp = new_task_smack(NULL, NULL, gfp);
	if (tsp == NULL)
1388
		return -ENOMEM;
1389 1390 1391

	cred->security = tsp;

1392 1393 1394 1395
	return 0;
}


1396
/**
1397 1398
 * smack_cred_free - "free" task-level security credentials
 * @cred: the credentials in question
1399 1400
 *
 */
1401
static void smack_cred_free(struct cred *cred)
1402
{
1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417
	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);
1418 1419
}

D
David Howells 已提交
1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430
/**
 * 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)
{
1431 1432
	struct task_smack *old_tsp = old->security;
	struct task_smack *new_tsp;
1433
	int rc;
1434

1435
	new_tsp = new_task_smack(old_tsp->smk_task, old_tsp->smk_task, gfp);
1436 1437 1438
	if (new_tsp == NULL)
		return -ENOMEM;

1439 1440 1441 1442
	rc = smk_copy_rules(&new_tsp->smk_rules, &old_tsp->smk_rules, gfp);
	if (rc != 0)
		return rc;

1443
	new->security = new_tsp;
D
David Howells 已提交
1444 1445 1446
	return 0;
}

1447 1448 1449 1450 1451 1452 1453 1454 1455
/**
 * 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)
{
1456 1457 1458 1459 1460
	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;
1461 1462 1463 1464 1465
	mutex_init(&new_tsp->smk_rules_lock);
	INIT_LIST_HEAD(&new_tsp->smk_rules);


	/* cbs copy rule list */
1466 1467
}

1468 1469
/**
 * smack_kernel_act_as - Set the subjective context in a set of credentials
1470 1471
 * @new: points to the set of credentials to be modified.
 * @secid: specifies the security ID to be set
1472 1473 1474 1475 1476
 *
 * Set the security data for a kernel service.
 */
static int smack_kernel_act_as(struct cred *new, u32 secid)
{
1477
	struct task_smack *new_tsp = new->security;
1478 1479 1480 1481 1482
	char *smack = smack_from_secid(secid);

	if (smack == NULL)
		return -EINVAL;

1483
	new_tsp->smk_task = smack;
1484 1485 1486 1487 1488
	return 0;
}

/**
 * smack_kernel_create_files_as - Set the file creation label in a set of creds
1489 1490
 * @new: points to the set of credentials to be modified
 * @inode: points to the inode to use as a reference
1491 1492 1493 1494 1495 1496 1497 1498
 *
 * 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;
1499
	struct task_smack *tsp = new->security;
1500

1501 1502
	tsp->smk_forked = isp->smk_inode;
	tsp->smk_task = isp->smk_inode;
1503 1504 1505
	return 0;
}

E
Etienne Basset 已提交
1506 1507 1508
/**
 * smk_curacc_on_task - helper to log task related access
 * @p: the task object
1509 1510
 * @access: the access requested
 * @caller: name of the calling function for audit
E
Etienne Basset 已提交
1511 1512 1513
 *
 * Return 0 if access is permitted
 */
1514 1515
static int smk_curacc_on_task(struct task_struct *p, int access,
				const char *caller)
E
Etienne Basset 已提交
1516 1517 1518
{
	struct smk_audit_info ad;

1519
	smk_ad_init(&ad, caller, LSM_AUDIT_DATA_TASK);
E
Etienne Basset 已提交
1520
	smk_ad_setfield_u_tsk(&ad, p);
1521
	return smk_curacc(smk_of_task(task_security(p)), access, &ad);
E
Etienne Basset 已提交
1522 1523
}

1524 1525 1526 1527 1528 1529 1530 1531 1532
/**
 * 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)
{
1533
	return smk_curacc_on_task(p, MAY_WRITE, __func__);
1534 1535 1536 1537 1538 1539 1540 1541 1542 1543
}

/**
 * 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)
{
1544
	return smk_curacc_on_task(p, MAY_READ, __func__);
1545 1546 1547 1548 1549 1550 1551 1552 1553 1554
}

/**
 * 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)
{
1555
	return smk_curacc_on_task(p, MAY_READ, __func__);
1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566
}

/**
 * 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)
{
1567
	*secid = smack_to_secid(smk_of_task(task_security(p)));
1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578
}

/**
 * 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)
{
1579 1580 1581 1582
	int rc;

	rc = cap_task_setnice(p, nice);
	if (rc == 0)
1583
		rc = smk_curacc_on_task(p, MAY_WRITE, __func__);
1584
	return rc;
1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595
}

/**
 * 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)
{
1596 1597 1598 1599
	int rc;

	rc = cap_task_setioprio(p, ioprio);
	if (rc == 0)
1600
		rc = smk_curacc_on_task(p, MAY_WRITE, __func__);
1601
	return rc;
1602 1603 1604 1605 1606 1607 1608 1609 1610 1611
}

/**
 * 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)
{
1612
	return smk_curacc_on_task(p, MAY_READ, __func__);
1613 1614 1615 1616 1617 1618 1619 1620 1621 1622
}

/**
 * smack_task_setscheduler - Smack check on setting scheduler
 * @p: the task object
 * @policy: unused
 * @lp: unused
 *
 * Return 0 if read access is permitted
 */
1623
static int smack_task_setscheduler(struct task_struct *p)
1624
{
1625 1626
	int rc;

1627
	rc = cap_task_setscheduler(p);
1628
	if (rc == 0)
1629
		rc = smk_curacc_on_task(p, MAY_WRITE, __func__);
1630
	return rc;
1631 1632 1633 1634 1635 1636 1637 1638 1639 1640
}

/**
 * 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)
{
1641
	return smk_curacc_on_task(p, MAY_READ, __func__);
1642 1643 1644 1645 1646 1647 1648 1649 1650 1651
}

/**
 * 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)
{
1652
	return smk_curacc_on_task(p, MAY_WRITE, __func__);
1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669
}

/**
 * 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
1670 1671 1672 1673
	struct smk_audit_info ad;

	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
	smk_ad_setfield_u_tsk(&ad, p);
1674 1675 1676 1677 1678
	/*
	 * Sending a signal requires that the sender
	 * can write the receiver.
	 */
	if (secid == 0)
1679 1680
		return smk_curacc(smk_of_task(task_security(p)), MAY_WRITE,
				  &ad);
1681 1682 1683 1684 1685
	/*
	 * 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.
	 */
1686 1687
	return smk_access(smack_from_secid(secid),
			  smk_of_task(task_security(p)), MAY_WRITE, &ad);
1688 1689 1690 1691 1692 1693 1694 1695 1696 1697
}

/**
 * smack_task_wait - Smack access check for waiting
 * @p: task to wait for
 *
 * Returns 0 if current can wait for p, error code otherwise
 */
static int smack_task_wait(struct task_struct *p)
{
E
Etienne Basset 已提交
1698
	struct smk_audit_info ad;
1699 1700
	char *sp = smk_of_current();
	char *tsp = smk_of_forked(task_security(p));
1701 1702
	int rc;

E
Etienne Basset 已提交
1703
	/* we don't log here, we can be overriden */
1704
	rc = smk_access(tsp, sp, MAY_WRITE, NULL);
1705
	if (rc == 0)
E
Etienne Basset 已提交
1706
		goto out_log;
1707 1708 1709 1710 1711 1712 1713

	/*
	 * Allow the operation to succeed if either task
	 * has privilege to perform operations that might
	 * account for the smack labels having gotten to
	 * be different in the first place.
	 *
1714
	 * This breaks the strict subject/object access
1715 1716 1717 1718
	 * control ideal, taking the object's privilege
	 * state into account in the decision as well as
	 * the smack value.
	 */
1719
	if (capable(CAP_MAC_OVERRIDE) || has_capability(p, CAP_MAC_OVERRIDE))
E
Etienne Basset 已提交
1720 1721 1722 1723 1724
		rc = 0;
	/* we log only if we didn't get overriden */
 out_log:
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
	smk_ad_setfield_u_tsk(&ad, p);
1725
	smack_log(tsp, sp, MAY_WRITE, rc, &ad);
1726 1727 1728 1729 1730 1731
	return rc;
}

/**
 * smack_task_to_inode - copy task smack into the inode blob
 * @p: task to copy from
1732
 * @inode: inode to copy to
1733 1734 1735 1736 1737 1738
 *
 * 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;
1739
	isp->smk_inode = smk_of_task(task_security(p));
1740 1741 1742 1743 1744 1745 1746 1747 1748 1749
}

/*
 * Socket hooks.
 */

/**
 * smack_sk_alloc_security - Allocate a socket blob
 * @sk: the socket
 * @family: unused
1750
 * @gfp_flags: memory allocation flags
1751 1752 1753 1754 1755 1756 1757
 *
 * 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)
{
1758
	char *csp = smk_of_current();
1759 1760 1761 1762 1763 1764 1765 1766
	struct socket_smack *ssp;

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

	ssp->smk_in = csp;
	ssp->smk_out = csp;
1767
	ssp->smk_packet = NULL;
1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784

	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);
}

1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811
/**
* 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 ==
1812 1813 1814 1815
		    (siap->s_addr & (&snp->smk_mask)->s_addr)) {
			/* we have found the special CIPSO option */
			if (snp->smk_label == smack_cipso_option)
				return NULL;
1816
			return snp->smk_label;
1817
		}
1818 1819 1820 1821

	return NULL;
}

1822 1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836
/**
 * smack_set_catset - convert a capset to netlabel mls categories
 * @catset: the Smack categories
 * @sap: where to put the netlabel categories
 *
 * Allocates and fills attr.mls.cat
 */
static void smack_set_catset(char *catset, struct netlbl_lsm_secattr *sap)
{
	unsigned char *cp;
	unsigned char m;
	int cat;
	int rc;
	int byte;

1837
	if (!catset)
1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860
		return;

	sap->flags |= NETLBL_SECATTR_MLS_CAT;
	sap->attr.mls.cat = netlbl_secattr_catmap_alloc(GFP_ATOMIC);
	sap->attr.mls.cat->startbit = 0;

	for (cat = 1, cp = catset, byte = 0; byte < SMK_LABELLEN; cp++, byte++)
		for (m = 0x80; m != 0; m >>= 1, cat++) {
			if ((m & *cp) == 0)
				continue;
			rc = netlbl_secattr_catmap_setbit(sap->attr.mls.cat,
							  cat, GFP_ATOMIC);
		}
}

/**
 * smack_to_secattr - fill a secattr from a smack value
 * @smack: the smack value
 * @nlsp: where the result goes
 *
 * Casey says that CIPSO is good enough for now.
 * It can be used to effect.
 * It can also be abused to effect when necessary.
L
Lucas De Marchi 已提交
1861
 * Apologies to the TSIG group in general and GW in particular.
1862 1863 1864 1865 1866 1867
 */
static void smack_to_secattr(char *smack, struct netlbl_lsm_secattr *nlsp)
{
	struct smack_cipso cipso;
	int rc;

1868 1869
	nlsp->domain = smack;
	nlsp->flags = NETLBL_SECATTR_DOMAIN | NETLBL_SECATTR_MLS_LVL;
1870

1871 1872 1873 1874 1875 1876 1877
	rc = smack_to_cipso(smack, &cipso);
	if (rc == 0) {
		nlsp->attr.mls.lvl = cipso.smk_level;
		smack_set_catset(cipso.smk_catset, nlsp);
	} else {
		nlsp->attr.mls.lvl = smack_cipso_direct;
		smack_set_catset(smack, nlsp);
1878 1879 1880 1881 1882 1883
	}
}

/**
 * smack_netlabel - Set the secattr on a socket
 * @sk: the socket
1884
 * @labeled: socket label scheme
1885 1886 1887 1888 1889 1890
 *
 * Convert the outbound smack value (smk_out) to a
 * secattr and attach it to the socket.
 *
 * Returns 0 on success or an error code
 */
1891
static int smack_netlabel(struct sock *sk, int labeled)
1892
{
1893
	struct socket_smack *ssp = sk->sk_security;
1894
	struct netlbl_lsm_secattr secattr;
1895
	int rc = 0;
1896

1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913
	/*
	 * 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 {
		netlbl_secattr_init(&secattr);
		smack_to_secattr(ssp->smk_out, &secattr);
1914
		rc = netlbl_sock_setattr(sk, sk->sk_family, &secattr);
1915 1916 1917 1918 1919
		netlbl_secattr_destroy(&secattr);
	}

	bh_unlock_sock(sk);
	local_bh_enable();
1920

1921 1922 1923
	return rc;
}

1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940
/**
 * 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)
{
	int rc;
	int sk_lbl;
	char *hostsp;
	struct socket_smack *ssp = sk->sk_security;
E
Etienne Basset 已提交
1941
	struct smk_audit_info ad;
1942 1943 1944 1945

	rcu_read_lock();
	hostsp = smack_host_label(sap);
	if (hostsp != NULL) {
E
Etienne Basset 已提交
1946
#ifdef CONFIG_AUDIT
1947 1948
		struct lsm_network_audit net;

1949 1950 1951 1952
		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;
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#endif
1954
		sk_lbl = SMACK_UNLABELED_SOCKET;
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1955
		rc = smk_access(ssp->smk_out, hostsp, MAY_WRITE, &ad);
1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966
	} else {
		sk_lbl = SMACK_CIPSO_SOCKET;
		rc = 0;
	}
	rcu_read_unlock();
	if (rc != 0)
		return rc;

	return smack_netlabel(sk, sk_lbl);
}

1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985
/**
 * 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)
{
	char *sp;
	struct inode_smack *nsp = inode->i_security;
	struct socket_smack *ssp;
	struct socket *sock;
1986
	int rc = 0;
1987

1988
	if (value == NULL || size > SMK_LABELLEN || size == 0)
1989 1990 1991 1992 1993 1994 1995 1996
		return -EACCES;

	sp = smk_import(value, size);
	if (sp == NULL)
		return -EINVAL;

	if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
		nsp->smk_inode = sp;
1997
		nsp->smk_flags |= SMK_INODE_INSTANT;
1998 1999 2000 2001 2002 2003 2004 2005 2006
		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);
2007
	if (sock == NULL || sock->sk == NULL)
2008 2009 2010 2011 2012 2013 2014 2015
		return -EOPNOTSUPP;

	ssp = sock->sk->sk_security;

	if (strcmp(name, XATTR_SMACK_IPIN) == 0)
		ssp->smk_in = sp;
	else if (strcmp(name, XATTR_SMACK_IPOUT) == 0) {
		ssp->smk_out = sp;
C
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		if (sock->sk->sk_family != PF_UNIX) {
			rc = smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET);
			if (rc != 0)
				printk(KERN_WARNING
					"Smack: \"%s\" netlbl error %d.\n",
					__func__, -rc);
		}
2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043
	} else
		return -EOPNOTSUPP;

	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)
{
2044
	if (family != PF_INET || sock->sk == NULL)
2045 2046 2047 2048
		return 0;
	/*
	 * Set the outbound netlbl.
	 */
2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069
	return smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET);
}

/**
 * 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)
{
	if (sock->sk == NULL || sock->sk->sk_family != PF_INET)
		return 0;
	if (addrlen < sizeof(struct sockaddr_in))
		return -EINVAL;

2070
	return smack_netlabel_send(sock->sk, (struct sockaddr_in *)sap);
2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097 2098 2099 2100
}

/**
 * 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)
{
2101
	msg->security = smk_of_current();
2102 2103 2104 2105 2106 2107 2108 2109 2110 2111 2112 2113 2114 2115 2116 2117 2118 2119 2120 2121 2122 2123 2124 2125 2126 2127 2128 2129 2130 2131 2132 2133 2134 2135 2136
	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;

2137
	isp->security = smk_of_current();
2138 2139 2140 2141 2142 2143 2144 2145 2146 2147 2148 2149 2150 2151 2152 2153
	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;
}

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/**
 * 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;

#ifdef CONFIG_AUDIT
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
	ad.a.u.ipc_id = shp->shm_perm.id;
#endif
	return smk_curacc(ssp, access, &ad);
}

2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184
/**
 * 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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	return smk_curacc_shm(shp, may);
2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199 2200 2201 2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218
}

/**
 * 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;
	}
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	return smk_curacc_shm(shp, may);
2220 2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235
}

/**
 * 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);
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	return smk_curacc_shm(shp, may);
2237 2238 2239 2240 2241 2242 2243 2244 2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259
}

/**
 * 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;

2260
	isp->security = smk_of_current();
2261 2262 2263 2264 2265 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276
	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;
}

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/**
 * 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;

#ifdef CONFIG_AUDIT
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
	ad.a.u.ipc_id = sma->sem_perm.id;
#endif
	return smk_curacc(ssp, access, &ad);
}

2296 2297 2298 2299 2300 2301 2302 2303 2304 2305 2306 2307
/**
 * 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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	return smk_curacc_sem(sma, may);
2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324 2325 2326 2327 2328 2329 2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 2347
}

/**
 * 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;
	}

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Etienne Basset 已提交
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	return smk_curacc_sem(sma, may);
2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364
}

/**
 * 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);
2366 2367 2368 2369 2370 2371 2372 2373 2374 2375 2376 2377
}

/**
 * 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;

2378
	kisp->security = smk_of_current();
2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389 2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400 2401 2402 2403 2404 2405
	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;
}

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Etienne Basset 已提交
2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424
/**
 * 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;

#ifdef CONFIG_AUDIT
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
	ad.a.u.ipc_id = msq->q_perm.id;
#endif
	return smk_curacc(msp, access, &ad);
}

2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436
/**
 * 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);
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Etienne Basset 已提交
2437
	return smk_curacc_msq(msq, may);
2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 2467 2468 2469
}

/**
 * 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
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	return smk_curacc_msq(msq, may);
2471 2472 2473 2474 2475 2476 2477 2478 2479 2480 2481 2482 2483
}

/**
 * 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
2484
	int may;
2485

E
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2486 2487
	may = smack_flags_to_may(msqflg);
	return smk_curacc_msq(msq, may);
2488 2489 2490 2491 2492 2493 2494 2495 2496 2497 2498 2499 2500 2501 2502
}

/**
 * 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
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	return smk_curacc_msq(msq, MAY_READWRITE);
2504 2505 2506 2507 2508 2509 2510 2511 2512 2513 2514 2515
}

/**
 * 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;
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Etienne Basset 已提交
2516 2517
	int may = smack_flags_to_may(flag);
	struct smk_audit_info ad;
2518

E
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2519 2520 2521 2522 2523
#ifdef CONFIG_AUDIT
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
	ad.a.u.ipc_id = ipp->id;
#endif
	return smk_curacc(isp, may, &ad);
2524 2525
}

2526 2527
/**
 * smack_ipc_getsecid - Extract smack security id
2528
 * @ipp: the object permissions
2529 2530 2531 2532 2533 2534 2535 2536 2537
 * @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);
}

2538 2539
/**
 * smack_d_instantiate - Make sure the blob is correct on an inode
2540
 * @opt_dentry: dentry where inode will be attached
2541 2542 2543 2544 2545 2546 2547 2548 2549
 * @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;
2550
	char *csp = smk_of_current();
2551 2552
	char *fetched;
	char *final;
2553 2554
	char trattr[TRANS_TRUE_SIZE];
	int transflag = 0;
2555 2556 2557 2558 2559 2560 2561 2562 2563 2564 2565 2566 2567 2568 2569 2570 2571 2572 2573 2574 2575 2576 2577
	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;

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Casey Schaufler 已提交
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	/*
	 * 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) {
		isp->smk_inode = sbsp->smk_root;
		isp->smk_flags |= SMK_INODE_INSTANT;
		goto unlockandout;
	}

2590 2591 2592 2593 2594 2595 2596 2597 2598
	/*
	 * 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:
		/*
L
Lucas De Marchi 已提交
2599
		 * Casey says that it's a little embarrassing
2600 2601 2602 2603 2604 2605 2606 2607 2608 2609 2610 2611 2612 2613 2614 2615 2616 2617 2618 2619 2620
		 * that the smack file system doesn't do
		 * extended attributes.
		 */
		final = smack_known_star.smk_known;
		break;
	case PIPEFS_MAGIC:
		/*
		 * Casey says pipes are easy (?)
		 */
		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.
		 */
		final = csp;
		break;
	case SOCKFS_MAGIC:
		/*
C
Casey Schaufler 已提交
2621 2622
		 * Socket access is controlled by the socket
		 * structures associated with the task involved.
2623
		 */
C
Casey Schaufler 已提交
2624
		final = smack_known_star.smk_known;
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
		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
2651 2652 2653 2654 2655 2656 2657 2658 2659 2660
		 */

		/*
		 * UNIX domain sockets use lower level socket data.
		 */
		if (S_ISSOCK(inode->i_mode)) {
			final = smack_known_star.smk_known;
			break;
		}
		/*
2661 2662 2663 2664 2665 2666 2667 2668 2669 2670
		 * 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.
		 */
2671
		dp = dget(opt_dentry);
2672
		fetched = smk_fetch(XATTR_NAME_SMACK, inode, dp);
2673
		if (fetched != NULL) {
2674
			final = fetched;
2675 2676 2677 2678 2679 2680 2681 2682 2683 2684 2685
			if (S_ISDIR(inode->i_mode)) {
				trattr[0] = '\0';
				inode->i_op->getxattr(dp,
					XATTR_NAME_SMACKTRANSMUTE,
					trattr, TRANS_TRUE_SIZE);
				if (strncmp(trattr, TRANS_TRUE,
					    TRANS_TRUE_SIZE) == 0)
					transflag = SMK_INODE_TRANSMUTE;
			}
		}
		isp->smk_task = smk_fetch(XATTR_NAME_SMACKEXEC, inode, dp);
2686
		isp->smk_mmap = smk_fetch(XATTR_NAME_SMACKMMAP, inode, dp);
2687

2688 2689 2690 2691 2692 2693 2694 2695 2696
		dput(dp);
		break;
	}

	if (final == NULL)
		isp->smk_inode = csp;
	else
		isp->smk_inode = final;

2697
	isp->smk_flags |= (SMK_INODE_INSTANT | transflag);
2698 2699 2700 2701 2702 2703 2704 2705 2706 2707 2708 2709 2710 2711 2712 2713 2714 2715 2716 2717 2718 2719 2720 2721

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)
{
	char *cp;
	int slen;

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

2722
	cp = kstrdup(smk_of_task(task_security(p)), GFP_KERNEL);
2723 2724 2725 2726 2727 2728 2729 2730 2731 2732 2733 2734 2735 2736 2737 2738 2739 2740 2741 2742 2743 2744 2745
	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)
{
2746
	int rc;
2747
	struct task_smack *tsp;
2748
	struct task_smack *oldtsp;
D
David Howells 已提交
2749
	struct cred *new;
2750 2751 2752 2753 2754 2755 2756 2757 2758
	char *newsmack;

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

2759 2760 2761
	if (!capable(CAP_MAC_ADMIN))
		return -EPERM;

2762 2763 2764 2765 2766 2767 2768 2769 2770 2771
	if (value == NULL || size == 0 || size >= SMK_LABELLEN)
		return -EINVAL;

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

	newsmack = smk_import(value, size);
	if (newsmack == NULL)
		return -EINVAL;

2772 2773 2774 2775 2776 2777
	/*
	 * No process is ever allowed the web ("@") label.
	 */
	if (newsmack == smack_known_web.smk_known)
		return -EPERM;

2778
	oldtsp = p->cred->security;
D
David Howells 已提交
2779
	new = prepare_creds();
2780
	if (new == NULL)
D
David Howells 已提交
2781
		return -ENOMEM;
2782 2783

	tsp = new_task_smack(newsmack, oldtsp->smk_forked, GFP_KERNEL);
2784 2785 2786 2787
	if (tsp == NULL) {
		kfree(new);
		return -ENOMEM;
	}
2788 2789 2790 2791
	rc = smk_copy_rules(&tsp->smk_rules, &oldtsp->smk_rules, GFP_KERNEL);
	if (rc != 0)
		return rc;

2792
	new->security = tsp;
D
David Howells 已提交
2793
	commit_creds(new);
2794 2795 2796 2797 2798
	return size;
}

/**
 * smack_unix_stream_connect - Smack access on UDS
2799 2800
 * @sock: one sock
 * @other: the other sock
2801 2802 2803 2804 2805
 * @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
 */
2806 2807
static int smack_unix_stream_connect(struct sock *sock,
				     struct sock *other, struct sock *newsk)
2808
{
J
James Morris 已提交
2809 2810
	struct socket_smack *ssp = sock->sk_security;
	struct socket_smack *osp = other->sk_security;
2811
	struct socket_smack *nsp = newsk->sk_security;
E
Etienne Basset 已提交
2812
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
2813
	int rc = 0;
2814

2815 2816 2817
#ifdef CONFIG_AUDIT
	struct lsm_network_audit net;

2818
	smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
2819
	smk_ad_setfield_u_net_sk(&ad, other);
2820
#endif
C
Casey Schaufler 已提交
2821 2822 2823 2824

	if (!capable(CAP_MAC_OVERRIDE))
		rc = smk_access(ssp->smk_out, osp->smk_in, MAY_WRITE, &ad);

2825 2826 2827 2828 2829 2830 2831 2832
	/*
	 * Cross reference the peer labels for SO_PEERSEC.
	 */
	if (rc == 0) {
		nsp->smk_packet = ssp->smk_out;
		ssp->smk_packet = osp->smk_out;
	}

C
Casey Schaufler 已提交
2833
	return rc;
2834 2835 2836 2837 2838 2839 2840 2841 2842 2843 2844 2845
}

/**
 * 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
2846 2847
	struct socket_smack *ssp = sock->sk->sk_security;
	struct socket_smack *osp = other->sk->sk_security;
E
Etienne Basset 已提交
2848
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
2849
	int rc = 0;
2850

2851 2852 2853
#ifdef CONFIG_AUDIT
	struct lsm_network_audit net;

2854
	smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
E
Etienne Basset 已提交
2855
	smk_ad_setfield_u_net_sk(&ad, other->sk);
2856
#endif
C
Casey Schaufler 已提交
2857 2858 2859 2860 2861

	if (!capable(CAP_MAC_OVERRIDE))
		rc = smk_access(ssp->smk_out, osp->smk_in, MAY_WRITE, &ad);

	return rc;
2862 2863
}

2864 2865 2866
/**
 * smack_socket_sendmsg - Smack check based on destination host
 * @sock: the socket
2867
 * @msg: the message
2868 2869 2870 2871 2872 2873 2874 2875 2876 2877 2878 2879 2880 2881
 * @size: the size of the message
 *
 * Return 0 if the current subject can write to the destination
 * host. This is only a question if the destination is a single
 * label host.
 */
static int smack_socket_sendmsg(struct socket *sock, struct msghdr *msg,
				int size)
{
	struct sockaddr_in *sip = (struct sockaddr_in *) msg->msg_name;

	/*
	 * Perfectly reasonable for this to be NULL
	 */
2882
	if (sip == NULL || sip->sin_family != AF_INET)
2883 2884
		return 0;

2885
	return smack_netlabel_send(sock->sk, sip);
2886 2887
}

2888
/**
2889
 * smack_from_secattr - Convert a netlabel attr.mls.lvl/attr.mls.cat pair to smack
2890
 * @sap: netlabel secattr
2891
 * @ssp: socket security information
2892
 *
2893
 * Returns a pointer to a Smack label found on the label list.
2894
 */
2895 2896
static char *smack_from_secattr(struct netlbl_lsm_secattr *sap,
				struct socket_smack *ssp)
2897
{
2898
	struct smack_known *skp;
2899
	char smack[SMK_LABELLEN];
2900
	char *sp;
2901 2902
	int pcat;

2903
	if ((sap->flags & NETLBL_SECATTR_MLS_LVL) != 0) {
2904
		/*
2905
		 * Looks like a CIPSO packet.
2906 2907 2908
		 * If there are flags but no level netlabel isn't
		 * behaving the way we expect it to.
		 *
2909
		 * Get the categories, if any
2910 2911 2912 2913
		 * Without guidance regarding the smack value
		 * for the packet fall back on the network
		 * ambient value.
		 */
2914 2915 2916 2917 2918 2919 2920 2921 2922 2923 2924 2925 2926 2927
		memset(smack, '\0', SMK_LABELLEN);
		if ((sap->flags & NETLBL_SECATTR_MLS_CAT) != 0)
			for (pcat = -1;;) {
				pcat = netlbl_secattr_catmap_walk(
					sap->attr.mls.cat, pcat + 1);
				if (pcat < 0)
					break;
				smack_catset_bit(pcat, smack);
			}
		/*
		 * If it is CIPSO using smack direct mapping
		 * we are already done. WeeHee.
		 */
		if (sap->attr.mls.lvl == smack_cipso_direct) {
2928 2929 2930 2931 2932 2933 2934 2935 2936 2937 2938 2939 2940 2941 2942 2943 2944 2945 2946 2947 2948 2949 2950 2951 2952 2953
			/*
			 * The label sent is usually on the label list.
			 *
			 * If it is not we may still want to allow the
			 * delivery.
			 *
			 * If the recipient is accepting all packets
			 * because it is using the star ("*") label
			 * for SMACK64IPIN provide the web ("@") label
			 * so that a directed response will succeed.
			 * This is not very correct from a MAC point
			 * of view, but gets around the problem that
			 * locking prevents adding the newly discovered
			 * label to the list.
			 * The case where the recipient is not using
			 * the star label should obviously fail.
			 * The easy way to do this is to provide the
			 * star label as the subject label.
			 */
			skp = smk_find_entry(smack);
			if (skp != NULL)
				return skp->smk_known;
			if (ssp != NULL &&
			    ssp->smk_in == smack_known_star.smk_known)
				return smack_known_web.smk_known;
			return smack_known_star.smk_known;
2954 2955 2956 2957 2958
		}
		/*
		 * Look it up in the supplied table if it is not
		 * a direct mapping.
		 */
2959 2960 2961 2962 2963 2964
		sp = smack_from_cipso(sap->attr.mls.lvl, smack);
		if (sp != NULL)
			return sp;
		if (ssp != NULL && ssp->smk_in == smack_known_star.smk_known)
			return smack_known_web.smk_known;
		return smack_known_star.smk_known;
2965
	}
2966 2967 2968 2969 2970 2971 2972 2973 2974 2975 2976 2977 2978
	if ((sap->flags & NETLBL_SECATTR_SECID) != 0) {
		/*
		 * Looks like a fallback, which gives us a secid.
		 */
		sp = smack_from_secid(sap->attr.secid);
		/*
		 * 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.
		 */
		BUG_ON(sp == NULL);
2979
		return sp;
2980 2981
	}
	/*
2982 2983 2984
	 * Without guidance regarding the smack value
	 * for the packet fall back on the network
	 * ambient value.
2985
	 */
2986
	return smack_net_ambient;
2987 2988 2989 2990 2991 2992 2993 2994 2995 2996 2997 2998 2999
}

/**
 * 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;
3000
	char *csp;
3001
	int rc;
E
Etienne Basset 已提交
3002
	struct smk_audit_info ad;
3003
#ifdef CONFIG_AUDIT
3004
	struct lsm_network_audit net;
3005
#endif
3006 3007 3008 3009 3010 3011 3012
	if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6)
		return 0;

	/*
	 * Translate what netlabel gave us.
	 */
	netlbl_secattr_init(&secattr);
3013

3014
	rc = netlbl_skbuff_getattr(skb, sk->sk_family, &secattr);
3015 3016 3017
	if (rc == 0)
		csp = smack_from_secattr(&secattr, ssp);
	else
3018 3019
		csp = smack_net_ambient;

3020
	netlbl_secattr_destroy(&secattr);
3021

E
Etienne Basset 已提交
3022
#ifdef CONFIG_AUDIT
3023 3024 3025
	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;
E
Etienne Basset 已提交
3026 3027
	ipv4_skb_to_auditdata(skb, &ad.a, NULL);
#endif
3028 3029 3030 3031 3032 3033
	/*
	 * 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.
	 */
E
Etienne Basset 已提交
3034
	rc = smk_access(csp, ssp->smk_in, MAY_WRITE, &ad);
3035 3036 3037
	if (rc != 0)
		netlbl_skbuff_err(skb, rc, 0);
	return rc;
3038 3039 3040 3041 3042 3043 3044
}

/**
 * smack_socket_getpeersec_stream - pull in packet label
 * @sock: the socket
 * @optval: user's destination
 * @optlen: size thereof
3045
 * @len: max thereof
3046 3047 3048 3049 3050 3051 3052 3053
 *
 * 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;
3054 3055
	char *rcp = "";
	int slen = 1;
3056 3057 3058
	int rc = 0;

	ssp = sock->sk->sk_security;
3059 3060 3061 3062
	if (ssp->smk_packet != NULL) {
		rcp = ssp->smk_packet;
		slen = strlen(rcp) + 1;
	}
3063 3064 3065

	if (slen > len)
		rc = -ERANGE;
3066
	else if (copy_to_user(optval, rcp, slen) != 0)
3067 3068 3069 3070 3071 3072 3073 3074 3075 3076 3077
		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
3078
 * @sock: the peer socket
3079 3080 3081 3082 3083 3084 3085 3086 3087 3088
 * @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;
3089 3090
	struct socket_smack *ssp = NULL;
	char *sp;
C
Casey Schaufler 已提交
3091 3092
	int family = PF_UNSPEC;
	u32 s = 0;	/* 0 is the invalid secid */
3093 3094
	int rc;

C
Casey Schaufler 已提交
3095 3096 3097 3098 3099
	if (skb != NULL) {
		if (skb->protocol == htons(ETH_P_IP))
			family = PF_INET;
		else if (skb->protocol == htons(ETH_P_IPV6))
			family = PF_INET6;
3100
	}
C
Casey Schaufler 已提交
3101 3102
	if (family == PF_UNSPEC && sock != NULL)
		family = sock->sk->sk_family;
3103

C
Casey Schaufler 已提交
3104
	if (family == PF_UNIX) {
3105 3106
		ssp = sock->sk->sk_security;
		s = smack_to_secid(ssp->smk_out);
C
Casey Schaufler 已提交
3107 3108 3109 3110
	} else if (family == PF_INET || family == PF_INET6) {
		/*
		 * Translate what netlabel gave us.
		 */
3111 3112
		if (sock != NULL && sock->sk != NULL)
			ssp = sock->sk->sk_security;
C
Casey Schaufler 已提交
3113 3114 3115
		netlbl_secattr_init(&secattr);
		rc = netlbl_skbuff_getattr(skb, family, &secattr);
		if (rc == 0) {
3116 3117
			sp = smack_from_secattr(&secattr, ssp);
			s = smack_to_secid(sp);
C
Casey Schaufler 已提交
3118 3119 3120 3121
		}
		netlbl_secattr_destroy(&secattr);
	}
	*secid = s;
3122 3123 3124 3125 3126 3127
	if (s == 0)
		return -EINVAL;
	return 0;
}

/**
3128 3129 3130
 * smack_sock_graft - Initialize a newly created socket with an existing sock
 * @sk: child sock
 * @parent: parent socket
3131
 *
3132 3133
 * Set the smk_{in,out} state of an existing sock based on the process that
 * is creating the new socket.
3134 3135 3136 3137 3138
 */
static void smack_sock_graft(struct sock *sk, struct socket *parent)
{
	struct socket_smack *ssp;

3139 3140
	if (sk == NULL ||
	    (sk->sk_family != PF_INET && sk->sk_family != PF_INET6))
3141 3142 3143
		return;

	ssp = sk->sk_security;
3144
	ssp->smk_in = ssp->smk_out = smk_of_current();
3145
	/* cssp->smk_packet is already set in smack_inet_csk_clone() */
3146 3147 3148 3149 3150 3151 3152 3153 3154 3155 3156 3157 3158 3159
}

/**
 * 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)
{
3160
	u16 family = sk->sk_family;
3161
	struct socket_smack *ssp = sk->sk_security;
3162 3163 3164
	struct netlbl_lsm_secattr secattr;
	struct sockaddr_in addr;
	struct iphdr *hdr;
3165
	char *sp;
3166
	int rc;
E
Etienne Basset 已提交
3167
	struct smk_audit_info ad;
3168
#ifdef CONFIG_AUDIT
3169
	struct lsm_network_audit net;
3170
#endif
3171

3172 3173 3174
	/* handle mapped IPv4 packets arriving via IPv6 sockets */
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
		family = PF_INET;
3175

3176 3177
	netlbl_secattr_init(&secattr);
	rc = netlbl_skbuff_getattr(skb, family, &secattr);
3178
	if (rc == 0)
3179
		sp = smack_from_secattr(&secattr, ssp);
3180
	else
3181
		sp = smack_known_huh.smk_known;
3182 3183
	netlbl_secattr_destroy(&secattr);

E
Etienne Basset 已提交
3184
#ifdef CONFIG_AUDIT
3185 3186 3187
	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
3188 3189
	ipv4_skb_to_auditdata(skb, &ad.a, NULL);
#endif
3190
	/*
3191 3192
	 * Receiving a packet requires that the other end be able to write
	 * here. Read access is not required.
3193
	 */
3194
	rc = smk_access(sp, ssp->smk_in, MAY_WRITE, &ad);
3195 3196 3197 3198 3199 3200 3201
	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.
	 */
3202
	req->peer_secid = smack_to_secid(sp);
3203 3204 3205 3206

	/*
	 * 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
3207
	 * propagate the wire-label to the sock when it is created.
3208 3209 3210 3211 3212 3213 3214
	 */
	hdr = ip_hdr(skb);
	addr.sin_addr.s_addr = hdr->saddr;
	rcu_read_lock();
	if (smack_host_label(&addr) == NULL) {
		rcu_read_unlock();
		netlbl_secattr_init(&secattr);
3215
		smack_to_secattr(sp, &secattr);
3216 3217 3218 3219 3220 3221
		rc = netlbl_req_setattr(req, &secattr);
		netlbl_secattr_destroy(&secattr);
	} else {
		rcu_read_unlock();
		netlbl_req_delattr(req);
	}
3222 3223 3224 3225

	return rc;
}

3226 3227 3228 3229 3230 3231 3232 3233 3234 3235 3236 3237
/**
 * 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;

3238 3239 3240 3241
	if (req->peer_secid != 0)
		ssp->smk_packet = smack_from_secid(req->peer_secid);
	else
		ssp->smk_packet = NULL;
3242 3243
}

3244 3245 3246 3247 3248 3249 3250 3251 3252 3253 3254 3255
/*
 * 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
3256
 * @cred: the credentials to use
3257 3258 3259 3260 3261 3262
 * @flags: unused
 *
 * No allocation required
 *
 * Returns 0
 */
D
David Howells 已提交
3263
static int smack_key_alloc(struct key *key, const struct cred *cred,
3264 3265
			   unsigned long flags)
{
3266
	key->security = smk_of_task(cred->security);
3267 3268 3269 3270 3271 3272 3273 3274 3275 3276 3277 3278 3279 3280 3281 3282 3283
	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
3284
 * @cred: the credentials to use
3285 3286 3287 3288 3289 3290
 * @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,
D
David Howells 已提交
3291
				const struct cred *cred, key_perm_t perm)
3292 3293
{
	struct key *keyp;
E
Etienne Basset 已提交
3294
	struct smk_audit_info ad;
3295
	char *tsp = smk_of_task(cred->security);
3296 3297 3298 3299 3300 3301 3302 3303 3304 3305 3306 3307 3308

	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
	 */
3309
	if (tsp == NULL)
3310
		return -EACCES;
E
Etienne Basset 已提交
3311 3312 3313 3314 3315
#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
3316
	return smk_access(tsp, keyp->security,
E
Etienne Basset 已提交
3317
				 MAY_READWRITE, &ad);
3318 3319 3320
}
#endif /* CONFIG_KEYS */

3321 3322 3323 3324 3325 3326 3327 3328 3329 3330 3331 3332 3333 3334 3335 3336 3337 3338 3339 3340 3341 3342 3343 3344 3345 3346 3347 3348 3349 3350 3351 3352 3353
/*
 * 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;

3354
	if (op != Audit_equal && op != Audit_not_equal)
3355 3356 3357 3358 3359 3360 3361 3362 3363 3364 3365 3366 3367 3368 3369 3370 3371 3372 3373 3374 3375 3376 3377 3378 3379 3380 3381 3382 3383 3384 3385 3386 3387 3388 3389 3390 3391 3392 3393 3394 3395 3396 3397 3398 3399 3400 3401 3402 3403 3404 3405 3406 3407 3408 3409 3410 3411 3412 3413 3414 3415 3416 3417
		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)
{
	char *smack;
	char *rule = vrule;

	if (!rule) {
		audit_log(actx, GFP_KERNEL, AUDIT_SELINUX_ERR,
			  "Smack: missing rule\n");
		return -ENOENT;
	}

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

	smack = smack_from_secid(secid);

	/*
	 * No need to do string comparisons. If a match occurs,
	 * both pointers will point to the same smack_known
	 * label.
	 */
3418
	if (op == Audit_equal)
3419
		return (rule == smack);
3420
	if (op == Audit_not_equal)
3421 3422 3423 3424 3425 3426 3427 3428 3429 3430 3431 3432 3433 3434 3435 3436 3437 3438
		return (rule != smack);

	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 */

3439
/**
3440 3441 3442 3443 3444 3445 3446 3447 3448 3449 3450
 * 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)
{
	char *sp = smack_from_secid(secid);

3451 3452
	if (secdata)
		*secdata = sp;
3453 3454 3455 3456
	*seclen = strlen(sp);
	return 0;
}

3457
/**
3458 3459 3460 3461 3462 3463 3464
 * 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.
 */
3465
static int smack_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
3466 3467 3468 3469 3470
{
	*secid = smack_to_secid(secdata);
	return 0;
}

3471
/**
3472
 * smack_release_secctx - don't do anything.
3473 3474
 * @secdata: unused
 * @seclen: unused
3475 3476 3477 3478 3479 3480 3481
 *
 * Exists to make sure nothing gets done, and properly
 */
static void smack_release_secctx(char *secdata, u32 seclen)
{
}

3482 3483 3484 3485 3486 3487 3488 3489 3490 3491 3492 3493 3494 3495 3496 3497 3498 3499 3500 3501 3502
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;
}

3503 3504 3505
struct security_operations smack_ops = {
	.name =				"smack",

3506
	.ptrace_access_check =		smack_ptrace_access_check,
3507
	.ptrace_traceme =		smack_ptrace_traceme,
3508 3509 3510 3511 3512 3513 3514 3515 3516 3517
	.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,
	.sb_mount = 			smack_sb_mount,
	.sb_umount = 			smack_sb_umount,

3518
	.bprm_set_creds =		smack_bprm_set_creds,
3519 3520
	.bprm_committing_creds =	smack_bprm_committing_creds,
	.bprm_secureexec =		smack_bprm_secureexec,
3521

3522 3523 3524 3525 3526 3527 3528 3529 3530 3531 3532 3533 3534 3535 3536 3537 3538
	.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,
3539
	.inode_getsecid =		smack_inode_getsecid,
3540 3541 3542 3543 3544 3545 3546

	.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,
3547
	.file_mmap =			smack_file_mmap,
3548 3549 3550 3551
	.file_set_fowner = 		smack_file_set_fowner,
	.file_send_sigiotask = 		smack_file_send_sigiotask,
	.file_receive = 		smack_file_receive,

3552 3553
	.dentry_open =			smack_dentry_open,

3554
	.cred_alloc_blank =		smack_cred_alloc_blank,
3555
	.cred_free =			smack_cred_free,
D
David Howells 已提交
3556
	.cred_prepare =			smack_cred_prepare,
3557
	.cred_transfer =		smack_cred_transfer,
3558 3559
	.kernel_act_as =		smack_kernel_act_as,
	.kernel_create_files_as =	smack_kernel_create_files_as,
3560 3561 3562 3563 3564 3565 3566 3567 3568 3569 3570 3571 3572 3573 3574
	.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,
3575
	.ipc_getsecid =			smack_ipc_getsecid,
3576 3577 3578 3579 3580 3581 3582 3583 3584 3585 3586 3587 3588 3589 3590 3591 3592 3593 3594 3595 3596 3597 3598 3599 3600 3601 3602 3603 3604 3605 3606 3607

	.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,
3608 3609
	.socket_connect =		smack_socket_connect,
	.socket_sendmsg =		smack_socket_sendmsg,
3610 3611 3612 3613 3614 3615 3616
	.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,
3617
	.inet_csk_clone =		smack_inet_csk_clone,
3618

3619 3620 3621 3622 3623 3624
 /* 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 */
3625 3626 3627 3628 3629 3630 3631 3632 3633

 /* 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 */

3634
	.secid_to_secctx = 		smack_secid_to_secctx,
3635
	.secctx_to_secid = 		smack_secctx_to_secid,
3636
	.release_secctx = 		smack_release_secctx,
3637 3638 3639
	.inode_notifysecctx =		smack_inode_notifysecctx,
	.inode_setsecctx =		smack_inode_setsecctx,
	.inode_getsecctx =		smack_inode_getsecctx,
3640 3641
};

3642

3643
static __init void init_smack_known_list(void)
3644
{
3645 3646 3647 3648 3649 3650 3651 3652 3653 3654 3655 3656 3657 3658 3659 3660 3661 3662 3663 3664 3665 3666 3667 3668 3669 3670 3671 3672 3673 3674
	/*
	 * Initialize CIPSO locks
	 */
	spin_lock_init(&smack_known_huh.smk_cipsolock);
	spin_lock_init(&smack_known_hat.smk_cipsolock);
	spin_lock_init(&smack_known_star.smk_cipsolock);
	spin_lock_init(&smack_known_floor.smk_cipsolock);
	spin_lock_init(&smack_known_invalid.smk_cipsolock);
	spin_lock_init(&smack_known_web.smk_cipsolock);
	/*
	 * 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
	 */
3675 3676 3677 3678 3679 3680 3681 3682
	list_add(&smack_known_huh.list, &smack_known_list);
	list_add(&smack_known_hat.list, &smack_known_list);
	list_add(&smack_known_star.list, &smack_known_list);
	list_add(&smack_known_floor.list, &smack_known_list);
	list_add(&smack_known_invalid.list, &smack_known_list);
	list_add(&smack_known_web.list, &smack_known_list);
}

3683 3684 3685 3686 3687 3688 3689
/**
 * smack_init - initialize the smack system
 *
 * Returns 0
 */
static __init int smack_init(void)
{
D
David Howells 已提交
3690
	struct cred *cred;
3691
	struct task_smack *tsp;
D
David Howells 已提交
3692

3693 3694 3695 3696 3697
	if (!security_module_enable(&smack_ops))
		return 0;

	tsp = new_task_smack(smack_known_floor.smk_known,
				smack_known_floor.smk_known, GFP_KERNEL);
3698 3699 3700
	if (tsp == NULL)
		return -ENOMEM;

3701 3702 3703 3704 3705
	printk(KERN_INFO "Smack:  Initializing.\n");

	/*
	 * Set the security state for the initial task.
	 */
D
David Howells 已提交
3706
	cred = (struct cred *) current->cred;
3707
	cred->security = tsp;
3708

3709 3710
	/* initialize the smack_known_list */
	init_smack_known_list();
3711 3712 3713 3714 3715 3716 3717 3718 3719 3720 3721 3722 3723 3724 3725

	/*
	 * 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);