smack_lsm.c 85.6 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 <ext-jarkko.2.sakkinen@nokia.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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 *
 *	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 "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->mnt->mnt_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 = mnt->mnt_sb->s_security;
	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)
{
	struct task_smack *tsp = bprm->cred->security;
	struct inode_smack *isp;
	struct dentry *dp;
	int rc;

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

	if (bprm->cred_prepared)
		return 0;

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

	dp = bprm->file->f_dentry;

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

	isp = dp->d_inode->i_security;

	if (isp->smk_task != NULL)
		tsp->smk_task = isp->smk_task;

	return 0;
}

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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);
	}
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	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;

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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_READWRITE, &ad);
683 684 685

	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);
688 689 690 691 692 693 694 695 696 697 698 699 700
	}
	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
 */
701
static int smack_inode_permission(struct inode *inode, int mask)
702
{
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	struct smk_audit_info ad;
704
	int no_block = mask & MAY_NOT_BLOCK;
705 706

	mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
707 708 709 710 711
	/*
	 * No permission to check. Existence test. Yup, it's there.
	 */
	if (mask == 0)
		return 0;
712 713

	/* May be droppable after audit */
714
	if (no_block)
715
		return -ECHILD;
716
	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);
719 720 721 722 723 724 725 726 727 728 729
}

/**
 * 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;
731 732 733 734 735
	/*
	 * Need to allow for clearing the setuid bit.
	 */
	if (iattr->ia_valid & ATTR_FORCE)
		return 0;
736
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
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	smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
738

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	return smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
740 741 742 743 744 745 746 747 748 749 750
}

/**
 * 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;
752
	struct path path;
E
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754 755
	path.dentry = dentry;
	path.mnt = mnt;
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757
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
758
	smk_ad_setfield_u_fs_path(&ad, path);
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	return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ, &ad);
760 761 762 763 764 765 766 767 768 769 770 771 772 773
}

/**
 * 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
 */
774 775
static int smack_inode_setxattr(struct dentry *dentry, const char *name,
				const void *value, size_t size, int flags)
776
{
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	struct smk_audit_info ad;
778
	int rc = 0;
779

780 781
	if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
	    strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
782
	    strcmp(name, XATTR_NAME_SMACKIPOUT) == 0 ||
783 784
	    strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
	    strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
785 786
		if (!capable(CAP_MAC_ADMIN))
			rc = -EPERM;
787 788 789 790 791 792
		/*
		 * check label validity here so import wont fail on
		 * post_setxattr
		 */
		if (size == 0 || size >= SMK_LABELLEN ||
		    smk_import(value, size) == NULL)
793
			rc = -EINVAL;
794 795 796 797 798 799
	} 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;
800 801 802
	} else
		rc = cap_inode_setxattr(dentry, name, value, size, flags);

803
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
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	smk_ad_setfield_u_fs_path_dentry(&ad, dentry);

806
	if (rc == 0)
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		rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
808 809

	return rc;
810 811 812 813 814 815 816 817 818 819 820 821 822
}

/**
 * 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.
 */
823 824
static void smack_inode_post_setxattr(struct dentry *dentry, const char *name,
				      const void *value, size_t size, int flags)
825 826
{
	char *nsp;
827
	struct inode_smack *isp = dentry->d_inode->i_security;
828 829

	if (strcmp(name, XATTR_NAME_SMACK) == 0) {
830
		nsp = smk_import(value, size);
831 832 833 834
		if (nsp != NULL)
			isp->smk_inode = nsp;
		else
			isp->smk_inode = smack_known_invalid.smk_known;
835 836
	} else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0) {
		nsp = smk_import(value, size);
837 838 839 840
		if (nsp != NULL)
			isp->smk_task = nsp;
		else
			isp->smk_task = smack_known_invalid.smk_known;
841 842 843 844 845 846
	} 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;
847 848
	} else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0)
		isp->smk_flags |= SMK_INODE_TRANSMUTE;
849 850 851 852

	return;
}

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/**
854 855 856 857 858 859
 * smack_inode_getxattr - Smack check on getxattr
 * @dentry: the object
 * @name: unused
 *
 * Returns 0 if access is permitted, an error code otherwise
 */
860
static int smack_inode_getxattr(struct dentry *dentry, const char *name)
861
{
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	struct smk_audit_info ad;

864
	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);
868 869
}

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870
/**
871 872 873 874 875 876 877 878
 * 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
 */
879
static int smack_inode_removexattr(struct dentry *dentry, const char *name)
880
{
881
	struct inode_smack *isp;
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	struct smk_audit_info ad;
883
	int rc = 0;
884

885 886
	if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
	    strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
887
	    strcmp(name, XATTR_NAME_SMACKIPOUT) == 0 ||
888
	    strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
889 890
	    strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0 ||
	    strcmp(name, XATTR_NAME_SMACKMMAP)) {
891 892 893 894 895
		if (!capable(CAP_MAC_ADMIN))
			rc = -EPERM;
	} else
		rc = cap_inode_removexattr(dentry, name);

896
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
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	smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
898
	if (rc == 0)
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		rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
900

901 902 903
	if (rc == 0) {
		isp = dentry->d_inode->i_security;
		isp->smk_task = NULL;
904
		isp->smk_mmap = NULL;
905 906
	}

907
	return rc;
908 909 910 911 912 913 914
}

/**
 * smack_inode_getsecurity - get smack xattrs
 * @inode: the object
 * @name: attribute name
 * @buffer: where to put the result
915
 * @alloc: unused
916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945
 *
 * 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);
946
	if (sock == NULL || sock->sk == NULL)
947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987
		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;
}

988 989 990 991 992 993 994 995 996 997 998 999
/**
 * 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);
}

1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033
/*
 * 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)
{
1034
	file->f_security = smk_of_current();
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
	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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1064 1065
	struct smk_audit_info ad;

1066
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
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	smk_ad_setfield_u_fs_path(&ad, file->f_path);
1068 1069

	if (_IOC_DIR(cmd) & _IOC_WRITE)
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		rc = smk_curacc(file->f_security, MAY_WRITE, &ad);
1071 1072

	if (rc == 0 && (_IOC_DIR(cmd) & _IOC_READ))
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Etienne Basset 已提交
1073
		rc = smk_curacc(file->f_security, MAY_READ, &ad);
1074 1075 1076 1077 1078 1079 1080

	return rc;
}

/**
 * smack_file_lock - Smack check on file locking
 * @file: the object
1081
 * @cmd: unused
1082 1083 1084 1085 1086
 *
 * 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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1087 1088
	struct smk_audit_info ad;

1089 1090
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
	smk_ad_setfield_u_fs_path(&ad, file->f_path);
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1091
	return smk_curacc(file->f_security, MAY_WRITE, &ad);
1092 1093 1094 1095 1096 1097 1098 1099
}

/**
 * smack_file_fcntl - Smack check on fcntl
 * @file: the object
 * @cmd: what action to check
 * @arg: unused
 *
1100 1101 1102 1103
 * Generally these operations are harmless.
 * File locking operations present an obvious mechanism
 * for passing information, so they require write access.
 *
1104 1105 1106 1107 1108
 * 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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1109
	struct smk_audit_info ad;
1110
	int rc = 0;
1111

E
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1112

1113 1114 1115 1116 1117 1118
	switch (cmd) {
	case F_GETLK:
	case F_SETLK:
	case F_SETLKW:
	case F_SETOWN:
	case F_SETSIG:
1119 1120
		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
1121
		rc = smk_curacc(file->f_security, MAY_WRITE, &ad);
1122 1123
		break;
	default:
1124
		break;
1125 1126 1127 1128 1129
	}

	return rc;
}

1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144
/**
 * 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)
{
1145
	struct smack_known *skp;
1146 1147 1148 1149
	struct smack_rule *srp;
	struct task_smack *tsp;
	char *sp;
	char *msmack;
1150
	char *osmack;
1151 1152
	struct inode_smack *isp;
	struct dentry *dp;
1153 1154 1155
	int may;
	int mmay;
	int tmay;
1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177
	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();
1178
	skp = smk_find_entry(sp);
1179 1180 1181 1182 1183 1184 1185 1186
	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.
	 */
1187
	list_for_each_entry_rcu(srp, &skp->smk_rules, list) {
1188
		osmack = srp->smk_object;
1189 1190 1191
		/*
		 * Matching labels always allows access.
		 */
1192
		if (msmack == osmack)
1193
			continue;
1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215
		/*
		 * 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.
		 */
1216 1217
		skp = smk_find_entry(msmack);
		mmay = smk_access_entry(msmack, osmack, &skp->smk_rules);
1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228
		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;
1229

1230 1231 1232 1233 1234
		/*
		 * If there is any access available to current that is
		 * not available to a SMACK64MMAP subject
		 * deny access.
		 */
1235
		if ((may | mmay) != mmay) {
1236
			rc = -EACCES;
1237
			break;
1238
		}
1239 1240 1241 1242 1243 1244 1245
	}

	rcu_read_unlock();

	return rc;
}

1246 1247 1248 1249 1250 1251 1252 1253 1254
/**
 * 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)
{
1255
	file->f_security = smk_of_current();
1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274
	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;
1275
	char *tsp = smk_of_task(tsk->cred->security);
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1276
	struct smk_audit_info ad;
1277 1278 1279 1280 1281

	/*
	 * struct fown_struct is never outside the context of a struct file
	 */
	file = container_of(fown, struct file, f_owner);
1282

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1283 1284
	/* we don't log here as rc can be overriden */
	rc = smk_access(file->f_security, tsp, MAY_WRITE, NULL);
1285
	if (rc != 0 && has_capability(tsk, CAP_MAC_OVERRIDE))
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1286 1287 1288 1289 1290
		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);
1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302
	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
1303
	struct smk_audit_info ad;
1304

E
Etienne Basset 已提交
1305 1306
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
	smk_ad_setfield_u_fs_path(&ad, file->f_path);
1307 1308 1309 1310 1311 1312 1313 1314
	/*
	 * 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
1315
	return smk_curacc(file->f_security, may, &ad);
1316 1317
}

1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335
/**
 * 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;
}

1336 1337 1338 1339
/*
 * Task hooks
 */

1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350
/**
 * 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)
{
1351 1352 1353 1354
	struct task_smack *tsp;

	tsp = new_task_smack(NULL, NULL, gfp);
	if (tsp == NULL)
1355
		return -ENOMEM;
1356 1357 1358

	cred->security = tsp;

1359 1360 1361 1362
	return 0;
}


1363
/**
1364 1365
 * smack_cred_free - "free" task-level security credentials
 * @cred: the credentials in question
1366 1367
 *
 */
1368
static void smack_cred_free(struct cred *cred)
1369
{
1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384
	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);
1385 1386
}

D
David Howells 已提交
1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397
/**
 * 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)
{
1398 1399
	struct task_smack *old_tsp = old->security;
	struct task_smack *new_tsp;
1400
	int rc;
1401

1402
	new_tsp = new_task_smack(old_tsp->smk_task, old_tsp->smk_task, gfp);
1403 1404 1405
	if (new_tsp == NULL)
		return -ENOMEM;

1406 1407 1408 1409
	rc = smk_copy_rules(&new_tsp->smk_rules, &old_tsp->smk_rules, gfp);
	if (rc != 0)
		return rc;

1410
	new->security = new_tsp;
D
David Howells 已提交
1411 1412 1413
	return 0;
}

1414 1415 1416 1417 1418 1419 1420 1421 1422
/**
 * 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)
{
1423 1424 1425 1426 1427
	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;
1428 1429 1430 1431 1432
	mutex_init(&new_tsp->smk_rules_lock);
	INIT_LIST_HEAD(&new_tsp->smk_rules);


	/* cbs copy rule list */
1433 1434
}

1435 1436
/**
 * smack_kernel_act_as - Set the subjective context in a set of credentials
1437 1438
 * @new: points to the set of credentials to be modified.
 * @secid: specifies the security ID to be set
1439 1440 1441 1442 1443
 *
 * Set the security data for a kernel service.
 */
static int smack_kernel_act_as(struct cred *new, u32 secid)
{
1444
	struct task_smack *new_tsp = new->security;
1445 1446 1447 1448 1449
	char *smack = smack_from_secid(secid);

	if (smack == NULL)
		return -EINVAL;

1450
	new_tsp->smk_task = smack;
1451 1452 1453 1454 1455
	return 0;
}

/**
 * smack_kernel_create_files_as - Set the file creation label in a set of creds
1456 1457
 * @new: points to the set of credentials to be modified
 * @inode: points to the inode to use as a reference
1458 1459 1460 1461 1462 1463 1464 1465
 *
 * 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;
1466
	struct task_smack *tsp = new->security;
1467

1468 1469
	tsp->smk_forked = isp->smk_inode;
	tsp->smk_task = isp->smk_inode;
1470 1471 1472
	return 0;
}

E
Etienne Basset 已提交
1473 1474 1475
/**
 * smk_curacc_on_task - helper to log task related access
 * @p: the task object
1476 1477
 * @access: the access requested
 * @caller: name of the calling function for audit
E
Etienne Basset 已提交
1478 1479 1480
 *
 * Return 0 if access is permitted
 */
1481 1482
static int smk_curacc_on_task(struct task_struct *p, int access,
				const char *caller)
E
Etienne Basset 已提交
1483 1484 1485
{
	struct smk_audit_info ad;

1486
	smk_ad_init(&ad, caller, LSM_AUDIT_DATA_TASK);
E
Etienne Basset 已提交
1487
	smk_ad_setfield_u_tsk(&ad, p);
1488
	return smk_curacc(smk_of_task(task_security(p)), access, &ad);
E
Etienne Basset 已提交
1489 1490
}

1491 1492 1493 1494 1495 1496 1497 1498 1499
/**
 * 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)
{
1500
	return smk_curacc_on_task(p, MAY_WRITE, __func__);
1501 1502 1503 1504 1505 1506 1507 1508 1509 1510
}

/**
 * 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)
{
1511
	return smk_curacc_on_task(p, MAY_READ, __func__);
1512 1513 1514 1515 1516 1517 1518 1519 1520 1521
}

/**
 * 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)
{
1522
	return smk_curacc_on_task(p, MAY_READ, __func__);
1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533
}

/**
 * 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)
{
1534
	*secid = smack_to_secid(smk_of_task(task_security(p)));
1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545
}

/**
 * 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)
{
1546 1547 1548 1549
	int rc;

	rc = cap_task_setnice(p, nice);
	if (rc == 0)
1550
		rc = smk_curacc_on_task(p, MAY_WRITE, __func__);
1551
	return rc;
1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562
}

/**
 * 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)
{
1563 1564 1565 1566
	int rc;

	rc = cap_task_setioprio(p, ioprio);
	if (rc == 0)
1567
		rc = smk_curacc_on_task(p, MAY_WRITE, __func__);
1568
	return rc;
1569 1570 1571 1572 1573 1574 1575 1576 1577 1578
}

/**
 * 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)
{
1579
	return smk_curacc_on_task(p, MAY_READ, __func__);
1580 1581 1582 1583 1584 1585 1586 1587 1588 1589
}

/**
 * smack_task_setscheduler - Smack check on setting scheduler
 * @p: the task object
 * @policy: unused
 * @lp: unused
 *
 * Return 0 if read access is permitted
 */
1590
static int smack_task_setscheduler(struct task_struct *p)
1591
{
1592 1593
	int rc;

1594
	rc = cap_task_setscheduler(p);
1595
	if (rc == 0)
1596
		rc = smk_curacc_on_task(p, MAY_WRITE, __func__);
1597
	return rc;
1598 1599 1600 1601 1602 1603 1604 1605 1606 1607
}

/**
 * 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)
{
1608
	return smk_curacc_on_task(p, MAY_READ, __func__);
1609 1610 1611 1612 1613 1614 1615 1616 1617 1618
}

/**
 * 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)
{
1619
	return smk_curacc_on_task(p, MAY_WRITE, __func__);
1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636
}

/**
 * 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
1637 1638 1639 1640
	struct smk_audit_info ad;

	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
	smk_ad_setfield_u_tsk(&ad, p);
1641 1642 1643 1644 1645
	/*
	 * Sending a signal requires that the sender
	 * can write the receiver.
	 */
	if (secid == 0)
1646 1647
		return smk_curacc(smk_of_task(task_security(p)), MAY_WRITE,
				  &ad);
1648 1649 1650 1651 1652
	/*
	 * 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.
	 */
1653 1654
	return smk_access(smack_from_secid(secid),
			  smk_of_task(task_security(p)), MAY_WRITE, &ad);
1655 1656 1657 1658 1659 1660 1661 1662 1663 1664
}

/**
 * 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
1665
	struct smk_audit_info ad;
1666 1667
	char *sp = smk_of_current();
	char *tsp = smk_of_forked(task_security(p));
1668 1669
	int rc;

E
Etienne Basset 已提交
1670
	/* we don't log here, we can be overriden */
1671
	rc = smk_access(tsp, sp, MAY_WRITE, NULL);
1672
	if (rc == 0)
E
Etienne Basset 已提交
1673
		goto out_log;
1674 1675 1676 1677 1678 1679 1680

	/*
	 * 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.
	 *
1681
	 * This breaks the strict subject/object access
1682 1683 1684 1685
	 * control ideal, taking the object's privilege
	 * state into account in the decision as well as
	 * the smack value.
	 */
1686
	if (capable(CAP_MAC_OVERRIDE) || has_capability(p, CAP_MAC_OVERRIDE))
E
Etienne Basset 已提交
1687 1688 1689 1690 1691
		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);
1692
	smack_log(tsp, sp, MAY_WRITE, rc, &ad);
1693 1694 1695 1696 1697 1698
	return rc;
}

/**
 * smack_task_to_inode - copy task smack into the inode blob
 * @p: task to copy from
1699
 * @inode: inode to copy to
1700 1701 1702 1703 1704 1705
 *
 * 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;
1706
	isp->smk_inode = smk_of_task(task_security(p));
1707 1708 1709 1710 1711 1712 1713 1714 1715 1716
}

/*
 * Socket hooks.
 */

/**
 * smack_sk_alloc_security - Allocate a socket blob
 * @sk: the socket
 * @family: unused
1717
 * @gfp_flags: memory allocation flags
1718 1719 1720 1721 1722 1723 1724
 *
 * 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)
{
1725
	char *csp = smk_of_current();
1726 1727 1728 1729 1730 1731 1732 1733
	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;
1734
	ssp->smk_packet = NULL;
1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751

	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);
}

1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778
/**
* 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 ==
1779 1780 1781 1782
		    (siap->s_addr & (&snp->smk_mask)->s_addr)) {
			/* we have found the special CIPSO option */
			if (snp->smk_label == smack_cipso_option)
				return NULL;
1783
			return snp->smk_label;
1784
		}
1785 1786 1787 1788

	return NULL;
}

1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803
/**
 * 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;

1804
	if (!catset)
1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825 1826 1827
		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
1828
 * Apologies to the TSIG group in general and GW in particular.
1829 1830 1831 1832 1833 1834
 */
static void smack_to_secattr(char *smack, struct netlbl_lsm_secattr *nlsp)
{
	struct smack_cipso cipso;
	int rc;

1835 1836
	nlsp->domain = smack;
	nlsp->flags = NETLBL_SECATTR_DOMAIN | NETLBL_SECATTR_MLS_LVL;
1837

1838 1839 1840 1841 1842 1843 1844
	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);
1845 1846 1847 1848 1849 1850
	}
}

/**
 * smack_netlabel - Set the secattr on a socket
 * @sk: the socket
1851
 * @labeled: socket label scheme
1852 1853 1854 1855 1856 1857
 *
 * Convert the outbound smack value (smk_out) to a
 * secattr and attach it to the socket.
 *
 * Returns 0 on success or an error code
 */
1858
static int smack_netlabel(struct sock *sk, int labeled)
1859
{
1860
	struct socket_smack *ssp = sk->sk_security;
1861
	struct netlbl_lsm_secattr secattr;
1862
	int rc = 0;
1863

1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880
	/*
	 * 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);
1881
		rc = netlbl_sock_setattr(sk, sk->sk_family, &secattr);
1882 1883 1884 1885 1886
		netlbl_secattr_destroy(&secattr);
	}

	bh_unlock_sock(sk);
	local_bh_enable();
1887

1888 1889 1890
	return rc;
}

1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907
/**
 * 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
1908
	struct smk_audit_info ad;
1909 1910 1911 1912 1913

	rcu_read_lock();
	hostsp = smack_host_label(sap);
	if (hostsp != NULL) {
		sk_lbl = SMACK_UNLABELED_SOCKET;
E
Etienne Basset 已提交
1914 1915 1916 1917 1918 1919 1920
#ifdef CONFIG_AUDIT
		smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_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;
#endif
		rc = smk_access(ssp->smk_out, hostsp, MAY_WRITE, &ad);
1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931
	} else {
		sk_lbl = SMACK_CIPSO_SOCKET;
		rc = 0;
	}
	rcu_read_unlock();
	if (rc != 0)
		return rc;

	return smack_netlabel(sk, sk_lbl);
}

1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950
/**
 * 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;
1951
	int rc = 0;
1952

1953
	if (value == NULL || size > SMK_LABELLEN || size == 0)
1954 1955 1956 1957 1958 1959 1960 1961
		return -EACCES;

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

	if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
		nsp->smk_inode = sp;
1962
		nsp->smk_flags |= SMK_INODE_INSTANT;
1963 1964 1965 1966 1967 1968 1969 1970 1971
		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);
1972
	if (sock == NULL || sock->sk == NULL)
1973 1974 1975 1976 1977 1978 1979 1980
		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
Casey Schaufler 已提交
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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);
		}
1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008
	} 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)
{
2009
	if (family != PF_INET || sock->sk == NULL)
2010 2011 2012 2013
		return 0;
	/*
	 * Set the outbound netlbl.
	 */
2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034
	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;

2035
	return smack_netlabel_send(sock->sk, (struct sockaddr_in *)sap);
2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065
}

/**
 * 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)
{
2066
	msg->security = smk_of_current();
2067 2068 2069 2070 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 2101
	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;

2102
	isp->security = smk_of_current();
2103 2104 2105 2106 2107 2108 2109 2110 2111 2112 2113 2114 2115 2116 2117 2118
	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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2119 2120 2121 2122 2123 2124 2125 2126 2127 2128 2129 2130 2131 2132 2133 2134 2135 2136 2137
/**
 * 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);
}

2138 2139 2140 2141 2142 2143 2144 2145 2146 2147 2148 2149
/**
 * 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);
2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162 2163 2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183
}

/**
 * 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);
2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199 2200
}

/**
 * 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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Etienne Basset 已提交
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	return smk_curacc_shm(shp, may);
2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224
}

/**
 * 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;

2225
	isp->security = smk_of_current();
2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 2236 2237 2238 2239 2240 2241
	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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2242 2243 2244 2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260
/**
 * 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);
}

2261 2262 2263 2264 2265 2266 2267 2268 2269 2270 2271 2272
/**
 * smack_sem_associate - Smack access check for sem
 * @sma: the object
 * @semflg: access requested
 *
 * Returns 0 if current has the requested access, error code otherwise
 */
static int smack_sem_associate(struct sem_array *sma, int semflg)
{
	int may;

	may = smack_flags_to_may(semflg);
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Etienne Basset 已提交
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	return smk_curacc_sem(sma, may);
2274 2275 2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301 2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312
}

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

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

E
Etienne Basset 已提交
2313
	return smk_curacc_sem(sma, may);
2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324 2325 2326 2327 2328 2329
}

/**
 * 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
2330
	return smk_curacc_sem(sma, MAY_READWRITE);
2331 2332 2333 2334 2335 2336 2337 2338 2339 2340 2341 2342
}

/**
 * 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;

2343
	kisp->security = smk_of_current();
2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364 2365 2366 2367 2368 2369 2370
	return 0;
}

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

	kisp->security = NULL;
}

/**
 * smack_of_msq - the smack pointer for the msq
 * @msq: the object
 *
 * Returns a pointer to the smack value
 */
static char *smack_of_msq(struct msg_queue *msq)
{
	return (char *)msq->q_perm.security;
}

E
Etienne Basset 已提交
2371 2372 2373 2374 2375 2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389
/**
 * 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);
}

2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400 2401
/**
 * smack_msg_queue_associate - Smack access check for msg_queue
 * @msq: the object
 * @msqflg: access requested
 *
 * Returns 0 if current has the requested access, error code otherwise
 */
static int smack_msg_queue_associate(struct msg_queue *msq, int msqflg)
{
	int may;

	may = smack_flags_to_may(msqflg);
E
Etienne Basset 已提交
2402
	return smk_curacc_msq(msq, may);
2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434
}

/**
 * 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
2435
	return smk_curacc_msq(msq, may);
2436 2437 2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448
}

/**
 * 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
2449
	int may;
2450

E
Etienne Basset 已提交
2451 2452
	may = smack_flags_to_may(msqflg);
	return smk_curacc_msq(msq, may);
2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 2467
}

/**
 * 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
2468
	return smk_curacc_msq(msq, MAY_READWRITE);
2469 2470 2471 2472 2473 2474 2475 2476 2477 2478 2479 2480
}

/**
 * smack_ipc_permission - Smack access for ipc_permission()
 * @ipp: the object permissions
 * @flag: access requested
 *
 * Returns 0 if current has read and write access, error code otherwise
 */
static int smack_ipc_permission(struct kern_ipc_perm *ipp, short flag)
{
	char *isp = ipp->security;
E
Etienne Basset 已提交
2481 2482
	int may = smack_flags_to_may(flag);
	struct smk_audit_info ad;
2483

E
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2484 2485 2486 2487 2488
#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);
2489 2490
}

2491 2492
/**
 * smack_ipc_getsecid - Extract smack security id
2493
 * @ipp: the object permissions
2494 2495 2496 2497 2498 2499 2500 2501 2502
 * @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);
}

2503 2504
/**
 * smack_d_instantiate - Make sure the blob is correct on an inode
2505
 * @opt_dentry: dentry where inode will be attached
2506 2507 2508 2509 2510 2511 2512 2513 2514
 * @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;
2515
	char *csp = smk_of_current();
2516 2517
	char *fetched;
	char *final;
2518 2519
	char trattr[TRANS_TRUE_SIZE];
	int transflag = 0;
2520 2521 2522 2523 2524 2525 2526 2527 2528 2529 2530 2531 2532 2533 2534 2535 2536 2537 2538 2539 2540 2541 2542
	struct dentry *dp;

	if (inode == NULL)
		return;

	isp = inode->i_security;

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

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

C
Casey Schaufler 已提交
2543 2544 2545 2546 2547 2548 2549 2550 2551 2552 2553 2554
	/*
	 * 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;
	}

2555 2556 2557 2558 2559 2560 2561 2562 2563
	/*
	 * 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
2564
		 * Casey says that it's a little embarrassing
2565 2566 2567 2568 2569 2570 2571 2572 2573 2574 2575 2576 2577 2578 2579 2580 2581 2582 2583 2584 2585
		 * 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
2586 2587
		 * Socket access is controlled by the socket
		 * structures associated with the task involved.
2588
		 */
C
Casey Schaufler 已提交
2589
		final = smack_known_star.smk_known;
2590 2591 2592 2593 2594 2595 2596 2597 2598 2599 2600 2601 2602 2603 2604 2605 2606 2607 2608 2609 2610 2611 2612 2613 2614 2615
		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
2616 2617 2618 2619 2620 2621 2622 2623 2624 2625
		 */

		/*
		 * UNIX domain sockets use lower level socket data.
		 */
		if (S_ISSOCK(inode->i_mode)) {
			final = smack_known_star.smk_known;
			break;
		}
		/*
2626 2627 2628 2629 2630 2631 2632 2633 2634 2635
		 * 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.
		 */
2636
		dp = dget(opt_dentry);
2637
		fetched = smk_fetch(XATTR_NAME_SMACK, inode, dp);
2638
		if (fetched != NULL) {
2639
			final = fetched;
2640 2641 2642 2643 2644 2645 2646 2647 2648 2649 2650
			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);
2651
		isp->smk_mmap = smk_fetch(XATTR_NAME_SMACKMMAP, inode, dp);
2652

2653 2654 2655 2656 2657 2658 2659 2660 2661
		dput(dp);
		break;
	}

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

2662
	isp->smk_flags |= (SMK_INODE_INSTANT | transflag);
2663 2664 2665 2666 2667 2668 2669 2670 2671 2672 2673 2674 2675 2676 2677 2678 2679 2680 2681 2682 2683 2684 2685 2686

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;

2687
	cp = kstrdup(smk_of_task(task_security(p)), GFP_KERNEL);
2688 2689 2690 2691 2692 2693 2694 2695 2696 2697 2698 2699 2700 2701 2702 2703 2704 2705 2706 2707 2708 2709 2710
	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)
{
2711
	int rc;
2712
	struct task_smack *tsp;
2713
	struct task_smack *oldtsp;
D
David Howells 已提交
2714
	struct cred *new;
2715 2716 2717 2718 2719 2720 2721 2722 2723
	char *newsmack;

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

2724 2725 2726
	if (!capable(CAP_MAC_ADMIN))
		return -EPERM;

2727 2728 2729 2730 2731 2732 2733 2734 2735 2736
	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;

2737 2738 2739 2740 2741 2742
	/*
	 * No process is ever allowed the web ("@") label.
	 */
	if (newsmack == smack_known_web.smk_known)
		return -EPERM;

2743
	oldtsp = p->cred->security;
D
David Howells 已提交
2744
	new = prepare_creds();
2745
	if (new == NULL)
D
David Howells 已提交
2746
		return -ENOMEM;
2747 2748

	tsp = new_task_smack(newsmack, oldtsp->smk_forked, GFP_KERNEL);
2749 2750 2751 2752
	if (tsp == NULL) {
		kfree(new);
		return -ENOMEM;
	}
2753 2754 2755 2756
	rc = smk_copy_rules(&tsp->smk_rules, &oldtsp->smk_rules, GFP_KERNEL);
	if (rc != 0)
		return rc;

2757
	new->security = tsp;
D
David Howells 已提交
2758
	commit_creds(new);
2759 2760 2761 2762 2763
	return size;
}

/**
 * smack_unix_stream_connect - Smack access on UDS
2764 2765
 * @sock: one sock
 * @other: the other sock
2766 2767 2768 2769 2770
 * @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
 */
2771 2772
static int smack_unix_stream_connect(struct sock *sock,
				     struct sock *other, struct sock *newsk)
2773
{
J
James Morris 已提交
2774 2775
	struct socket_smack *ssp = sock->sk_security;
	struct socket_smack *osp = other->sk_security;
2776
	struct socket_smack *nsp = newsk->sk_security;
E
Etienne Basset 已提交
2777
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
2778
	int rc = 0;
2779

E
Etienne Basset 已提交
2780
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NET);
2781
	smk_ad_setfield_u_net_sk(&ad, other);
C
Casey Schaufler 已提交
2782 2783 2784 2785

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

2786 2787 2788 2789 2790 2791 2792 2793
	/*
	 * 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
2794
	return rc;
2795 2796 2797 2798 2799 2800 2801 2802 2803 2804 2805 2806
}

/**
 * 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
2807 2808
	struct socket_smack *ssp = sock->sk->sk_security;
	struct socket_smack *osp = other->sk->sk_security;
E
Etienne Basset 已提交
2809
	struct smk_audit_info ad;
C
Casey Schaufler 已提交
2810
	int rc = 0;
2811

E
Etienne Basset 已提交
2812 2813
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NET);
	smk_ad_setfield_u_net_sk(&ad, other->sk);
C
Casey Schaufler 已提交
2814 2815 2816 2817 2818

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

	return rc;
2819 2820
}

2821 2822 2823
/**
 * smack_socket_sendmsg - Smack check based on destination host
 * @sock: the socket
2824
 * @msg: the message
2825 2826 2827 2828 2829 2830 2831 2832 2833 2834 2835 2836 2837 2838
 * @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
	 */
2839
	if (sip == NULL || sip->sin_family != AF_INET)
2840 2841
		return 0;

2842
	return smack_netlabel_send(sock->sk, sip);
2843 2844
}

2845
/**
2846
 * smack_from_secattr - Convert a netlabel attr.mls.lvl/attr.mls.cat pair to smack
2847
 * @sap: netlabel secattr
2848
 * @ssp: socket security information
2849
 *
2850
 * Returns a pointer to a Smack label found on the label list.
2851
 */
2852 2853
static char *smack_from_secattr(struct netlbl_lsm_secattr *sap,
				struct socket_smack *ssp)
2854
{
2855
	struct smack_known *skp;
2856
	char smack[SMK_LABELLEN];
2857
	char *sp;
2858 2859
	int pcat;

2860
	if ((sap->flags & NETLBL_SECATTR_MLS_LVL) != 0) {
2861
		/*
2862
		 * Looks like a CIPSO packet.
2863 2864 2865
		 * If there are flags but no level netlabel isn't
		 * behaving the way we expect it to.
		 *
2866
		 * Get the categories, if any
2867 2868 2869 2870
		 * Without guidance regarding the smack value
		 * for the packet fall back on the network
		 * ambient value.
		 */
2871 2872 2873 2874 2875 2876 2877 2878 2879 2880 2881 2882 2883 2884
		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) {
2885 2886 2887 2888 2889 2890 2891 2892 2893 2894 2895 2896 2897 2898 2899 2900 2901 2902 2903 2904 2905 2906 2907 2908 2909 2910
			/*
			 * 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;
2911 2912 2913 2914 2915
		}
		/*
		 * Look it up in the supplied table if it is not
		 * a direct mapping.
		 */
2916 2917 2918 2919 2920 2921
		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;
2922
	}
2923 2924 2925 2926 2927 2928 2929 2930 2931 2932 2933 2934 2935
	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);
2936
		return sp;
2937 2938
	}
	/*
2939 2940 2941
	 * Without guidance regarding the smack value
	 * for the packet fall back on the network
	 * ambient value.
2942
	 */
2943
	return smack_net_ambient;
2944 2945 2946 2947 2948 2949 2950 2951 2952 2953 2954 2955 2956
}

/**
 * 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;
2957
	char *csp;
2958
	int rc;
E
Etienne Basset 已提交
2959
	struct smk_audit_info ad;
2960 2961 2962 2963 2964 2965 2966
	if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6)
		return 0;

	/*
	 * Translate what netlabel gave us.
	 */
	netlbl_secattr_init(&secattr);
2967

2968
	rc = netlbl_skbuff_getattr(skb, sk->sk_family, &secattr);
2969 2970 2971
	if (rc == 0)
		csp = smack_from_secattr(&secattr, ssp);
	else
2972 2973
		csp = smack_net_ambient;

2974
	netlbl_secattr_destroy(&secattr);
2975

E
Etienne Basset 已提交
2976 2977 2978
#ifdef CONFIG_AUDIT
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NET);
	ad.a.u.net.family = sk->sk_family;
2979
	ad.a.u.net.netif = skb->skb_iif;
E
Etienne Basset 已提交
2980 2981
	ipv4_skb_to_auditdata(skb, &ad.a, NULL);
#endif
2982 2983 2984 2985 2986 2987
	/*
	 * 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
2988
	rc = smk_access(csp, ssp->smk_in, MAY_WRITE, &ad);
2989 2990 2991
	if (rc != 0)
		netlbl_skbuff_err(skb, rc, 0);
	return rc;
2992 2993 2994 2995 2996 2997 2998
}

/**
 * smack_socket_getpeersec_stream - pull in packet label
 * @sock: the socket
 * @optval: user's destination
 * @optlen: size thereof
2999
 * @len: max thereof
3000 3001 3002 3003 3004 3005 3006 3007
 *
 * 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;
3008 3009
	char *rcp = "";
	int slen = 1;
3010 3011 3012
	int rc = 0;

	ssp = sock->sk->sk_security;
3013 3014 3015 3016
	if (ssp->smk_packet != NULL) {
		rcp = ssp->smk_packet;
		slen = strlen(rcp) + 1;
	}
3017 3018 3019

	if (slen > len)
		rc = -ERANGE;
3020
	else if (copy_to_user(optval, rcp, slen) != 0)
3021 3022 3023 3024 3025 3026 3027 3028 3029 3030 3031
		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
3032
 * @sock: the peer socket
3033 3034 3035 3036 3037 3038 3039 3040 3041 3042
 * @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;
3043 3044
	struct socket_smack *ssp = NULL;
	char *sp;
C
Casey Schaufler 已提交
3045 3046
	int family = PF_UNSPEC;
	u32 s = 0;	/* 0 is the invalid secid */
3047 3048
	int rc;

C
Casey Schaufler 已提交
3049 3050 3051 3052 3053
	if (skb != NULL) {
		if (skb->protocol == htons(ETH_P_IP))
			family = PF_INET;
		else if (skb->protocol == htons(ETH_P_IPV6))
			family = PF_INET6;
3054
	}
C
Casey Schaufler 已提交
3055 3056
	if (family == PF_UNSPEC && sock != NULL)
		family = sock->sk->sk_family;
3057

C
Casey Schaufler 已提交
3058
	if (family == PF_UNIX) {
3059 3060
		ssp = sock->sk->sk_security;
		s = smack_to_secid(ssp->smk_out);
C
Casey Schaufler 已提交
3061 3062 3063 3064
	} else if (family == PF_INET || family == PF_INET6) {
		/*
		 * Translate what netlabel gave us.
		 */
3065 3066
		if (sock != NULL && sock->sk != NULL)
			ssp = sock->sk->sk_security;
C
Casey Schaufler 已提交
3067 3068 3069
		netlbl_secattr_init(&secattr);
		rc = netlbl_skbuff_getattr(skb, family, &secattr);
		if (rc == 0) {
3070 3071
			sp = smack_from_secattr(&secattr, ssp);
			s = smack_to_secid(sp);
C
Casey Schaufler 已提交
3072 3073 3074 3075
		}
		netlbl_secattr_destroy(&secattr);
	}
	*secid = s;
3076 3077 3078 3079 3080 3081
	if (s == 0)
		return -EINVAL;
	return 0;
}

/**
3082 3083 3084
 * smack_sock_graft - Initialize a newly created socket with an existing sock
 * @sk: child sock
 * @parent: parent socket
3085
 *
3086 3087
 * Set the smk_{in,out} state of an existing sock based on the process that
 * is creating the new socket.
3088 3089 3090 3091 3092
 */
static void smack_sock_graft(struct sock *sk, struct socket *parent)
{
	struct socket_smack *ssp;

3093 3094
	if (sk == NULL ||
	    (sk->sk_family != PF_INET && sk->sk_family != PF_INET6))
3095 3096 3097
		return;

	ssp = sk->sk_security;
3098
	ssp->smk_in = ssp->smk_out = smk_of_current();
3099
	/* cssp->smk_packet is already set in smack_inet_csk_clone() */
3100 3101 3102 3103 3104 3105 3106 3107 3108 3109 3110 3111 3112 3113
}

/**
 * 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)
{
3114
	u16 family = sk->sk_family;
3115
	struct socket_smack *ssp = sk->sk_security;
3116 3117 3118
	struct netlbl_lsm_secattr secattr;
	struct sockaddr_in addr;
	struct iphdr *hdr;
3119
	char *sp;
3120
	int rc;
E
Etienne Basset 已提交
3121
	struct smk_audit_info ad;
3122

3123 3124 3125
	/* handle mapped IPv4 packets arriving via IPv6 sockets */
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
		family = PF_INET;
3126

3127 3128
	netlbl_secattr_init(&secattr);
	rc = netlbl_skbuff_getattr(skb, family, &secattr);
3129
	if (rc == 0)
3130
		sp = smack_from_secattr(&secattr, ssp);
3131
	else
3132
		sp = smack_known_huh.smk_known;
3133 3134
	netlbl_secattr_destroy(&secattr);

E
Etienne Basset 已提交
3135 3136 3137
#ifdef CONFIG_AUDIT
	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NET);
	ad.a.u.net.family = family;
3138
	ad.a.u.net.netif = skb->skb_iif;
E
Etienne Basset 已提交
3139 3140
	ipv4_skb_to_auditdata(skb, &ad.a, NULL);
#endif
3141
	/*
3142 3143
	 * Receiving a packet requires that the other end be able to write
	 * here. Read access is not required.
3144
	 */
3145
	rc = smk_access(sp, ssp->smk_in, MAY_WRITE, &ad);
3146 3147 3148 3149 3150 3151 3152
	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.
	 */
3153
	req->peer_secid = smack_to_secid(sp);
3154 3155 3156 3157

	/*
	 * 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
3158
	 * propagate the wire-label to the sock when it is created.
3159 3160 3161 3162 3163 3164 3165
	 */
	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);
3166
		smack_to_secattr(sp, &secattr);
3167 3168 3169 3170 3171 3172
		rc = netlbl_req_setattr(req, &secattr);
		netlbl_secattr_destroy(&secattr);
	} else {
		rcu_read_unlock();
		netlbl_req_delattr(req);
	}
3173 3174 3175 3176

	return rc;
}

3177 3178 3179 3180 3181 3182 3183 3184 3185 3186 3187 3188
/**
 * 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;

3189 3190 3191 3192
	if (req->peer_secid != 0)
		ssp->smk_packet = smack_from_secid(req->peer_secid);
	else
		ssp->smk_packet = NULL;
3193 3194
}

3195 3196 3197 3198 3199 3200 3201 3202 3203 3204 3205 3206
/*
 * 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
3207
 * @cred: the credentials to use
3208 3209 3210 3211 3212 3213
 * @flags: unused
 *
 * No allocation required
 *
 * Returns 0
 */
D
David Howells 已提交
3214
static int smack_key_alloc(struct key *key, const struct cred *cred,
3215 3216
			   unsigned long flags)
{
3217
	key->security = smk_of_task(cred->security);
3218 3219 3220 3221 3222 3223 3224 3225 3226 3227 3228 3229 3230 3231 3232 3233 3234
	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
3235
 * @cred: the credentials to use
3236 3237 3238 3239 3240 3241
 * @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
3242
				const struct cred *cred, key_perm_t perm)
3243 3244
{
	struct key *keyp;
E
Etienne Basset 已提交
3245
	struct smk_audit_info ad;
3246
	char *tsp = smk_of_task(cred->security);
3247 3248 3249 3250 3251 3252 3253 3254 3255 3256 3257 3258 3259

	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
	 */
3260
	if (tsp == NULL)
3261
		return -EACCES;
E
Etienne Basset 已提交
3262 3263 3264 3265 3266
#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
3267
	return smk_access(tsp, keyp->security,
E
Etienne Basset 已提交
3268
				 MAY_READWRITE, &ad);
3269 3270 3271
}
#endif /* CONFIG_KEYS */

3272 3273 3274 3275 3276 3277 3278 3279 3280 3281 3282 3283 3284 3285 3286 3287 3288 3289 3290 3291 3292 3293 3294 3295 3296 3297 3298 3299 3300 3301 3302 3303 3304
/*
 * 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;

3305
	if (op != Audit_equal && op != Audit_not_equal)
3306 3307 3308 3309 3310 3311 3312 3313 3314 3315 3316 3317 3318 3319 3320 3321 3322 3323 3324 3325 3326 3327 3328 3329 3330 3331 3332 3333 3334 3335 3336 3337 3338 3339 3340 3341 3342 3343 3344 3345 3346 3347 3348 3349 3350 3351 3352 3353 3354 3355 3356 3357 3358 3359 3360 3361 3362 3363 3364 3365 3366 3367 3368
		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.
	 */
3369
	if (op == Audit_equal)
3370
		return (rule == smack);
3371
	if (op == Audit_not_equal)
3372 3373 3374 3375 3376 3377 3378 3379 3380 3381 3382 3383 3384 3385 3386 3387 3388 3389
		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 */

3390
/**
3391 3392 3393 3394 3395 3396 3397 3398 3399 3400 3401
 * 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);

3402 3403
	if (secdata)
		*secdata = sp;
3404 3405 3406 3407
	*seclen = strlen(sp);
	return 0;
}

3408
/**
3409 3410 3411 3412 3413 3414 3415
 * 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.
 */
3416
static int smack_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
3417 3418 3419 3420 3421
{
	*secid = smack_to_secid(secdata);
	return 0;
}

3422
/**
3423
 * smack_release_secctx - don't do anything.
3424 3425
 * @secdata: unused
 * @seclen: unused
3426 3427 3428 3429 3430 3431 3432
 *
 * Exists to make sure nothing gets done, and properly
 */
static void smack_release_secctx(char *secdata, u32 seclen)
{
}

3433 3434 3435 3436 3437 3438 3439 3440 3441 3442 3443 3444 3445 3446 3447 3448 3449 3450 3451 3452 3453
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;
}

3454 3455 3456
struct security_operations smack_ops = {
	.name =				"smack",

3457
	.ptrace_access_check =		smack_ptrace_access_check,
3458
	.ptrace_traceme =		smack_ptrace_traceme,
3459 3460 3461 3462 3463 3464 3465 3466 3467 3468
	.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,

3469 3470
	.bprm_set_creds =		smack_bprm_set_creds,

3471 3472 3473 3474 3475 3476 3477 3478 3479 3480 3481 3482 3483 3484 3485 3486 3487
	.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,
3488
	.inode_getsecid =		smack_inode_getsecid,
3489 3490 3491 3492 3493 3494 3495

	.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,
3496
	.file_mmap =			smack_file_mmap,
3497 3498 3499 3500
	.file_set_fowner = 		smack_file_set_fowner,
	.file_send_sigiotask = 		smack_file_send_sigiotask,
	.file_receive = 		smack_file_receive,

3501 3502
	.dentry_open =			smack_dentry_open,

3503
	.cred_alloc_blank =		smack_cred_alloc_blank,
3504
	.cred_free =			smack_cred_free,
D
David Howells 已提交
3505
	.cred_prepare =			smack_cred_prepare,
3506
	.cred_transfer =		smack_cred_transfer,
3507 3508
	.kernel_act_as =		smack_kernel_act_as,
	.kernel_create_files_as =	smack_kernel_create_files_as,
3509 3510 3511 3512 3513 3514 3515 3516 3517 3518 3519 3520 3521 3522 3523
	.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,
3524
	.ipc_getsecid =			smack_ipc_getsecid,
3525 3526 3527 3528 3529 3530 3531 3532 3533 3534 3535 3536 3537 3538 3539 3540 3541 3542 3543 3544 3545 3546 3547 3548 3549 3550 3551 3552 3553 3554 3555 3556

	.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,
3557 3558
	.socket_connect =		smack_socket_connect,
	.socket_sendmsg =		smack_socket_sendmsg,
3559 3560 3561 3562 3563 3564 3565
	.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,
3566
	.inet_csk_clone =		smack_inet_csk_clone,
3567

3568 3569 3570 3571 3572 3573
 /* 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 */
3574 3575 3576 3577 3578 3579 3580 3581 3582

 /* 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 */

3583
	.secid_to_secctx = 		smack_secid_to_secctx,
3584
	.secctx_to_secid = 		smack_secctx_to_secid,
3585
	.release_secctx = 		smack_release_secctx,
3586 3587 3588
	.inode_notifysecctx =		smack_inode_notifysecctx,
	.inode_setsecctx =		smack_inode_setsecctx,
	.inode_getsecctx =		smack_inode_getsecctx,
3589 3590
};

3591 3592 3593 3594 3595 3596 3597 3598 3599 3600 3601

static __init void init_smack_know_list(void)
{
	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);
}

3602 3603 3604 3605 3606 3607 3608
/**
 * smack_init - initialize the smack system
 *
 * Returns 0
 */
static __init int smack_init(void)
{
D
David Howells 已提交
3609
	struct cred *cred;
3610
	struct task_smack *tsp;
D
David Howells 已提交
3611

3612 3613 3614 3615 3616
	if (!security_module_enable(&smack_ops))
		return 0;

	tsp = new_task_smack(smack_known_floor.smk_known,
				smack_known_floor.smk_known, GFP_KERNEL);
3617 3618 3619
	if (tsp == NULL)
		return -ENOMEM;

3620 3621 3622 3623 3624
	printk(KERN_INFO "Smack:  Initializing.\n");

	/*
	 * Set the security state for the initial task.
	 */
D
David Howells 已提交
3625
	cred = (struct cred *) current->cred;
3626
	cred->security = tsp;
3627

3628
	/* initialize the smack_know_list */
3629
	init_smack_know_list();
3630 3631 3632 3633 3634 3635 3636 3637 3638 3639 3640 3641 3642 3643 3644 3645 3646 3647 3648 3649 3650 3651 3652
	/*
	 * Initialize 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);

	/*
	 * 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);