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/* Updated: Karl MacMillan <kmacmillan@tresys.com>
*
* Added conditional policy language extensions
*
* Updated: Hewlett-Packard <paul.moore@hp.com>
*
* Added support for the policy capability bitmap
*
* Copyright (C) 2007 Hewlett-Packard Development Company, L.P.
* Copyright (C) 2003 - 2004 Tresys Technology, LLC
* Copyright (C) 2004 Red Hat, Inc., James Morris <jmorris@redhat.com>
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, version 2.
*/
#include <linux/kernel.h>
#include <linux/pagemap.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/fs.h>
#include <linux/mutex.h>
#include <linux/init.h>
#include <linux/string.h>
#include <linux/security.h>
#include <linux/major.h>
#include <linux/seq_file.h>
#include <linux/percpu.h>
#include <linux/audit.h>
#include <linux/uaccess.h>
/* selinuxfs pseudo filesystem for exporting the security policy API.
Based on the proc code and the fs/nfsd/nfsctl.c code. */
#include "flask.h"
#include "avc.h"
#include "avc_ss.h"
#include "security.h"
#include "objsec.h"
#include "conditional.h"
/* Policy capability filenames */
static char *policycap_names[] = {
"network_peer_controls",
"open_perms"
};
unsigned int selinux_checkreqprot = CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
static int __init checkreqprot_setup(char *str)
{
unsigned long checkreqprot;
if (!strict_strtoul(str, 0, &checkreqprot))
selinux_checkreqprot = checkreqprot ? 1 : 0;
return 1;
}
__setup("checkreqprot=", checkreqprot_setup);
static DEFINE_MUTEX(sel_mutex);
/* global data for booleans */
static struct dentry *bool_dir;
static int bool_num;
static char **bool_pending_names;
static int *bool_pending_values;
/* global data for classes */
static struct dentry *class_dir;
static unsigned long last_class_ino;
/* global data for policy capabilities */
static struct dentry *policycap_dir;
extern void selnl_notify_setenforce(int val);
/* Check whether a task is allowed to use a security operation. */
static int task_has_security(struct task_struct *tsk,
u32 perms)
{
const struct task_security_struct *tsec;
u32 sid = 0;
rcu_read_lock();
tsec = __task_cred(tsk)->security;
if (tsec)
sid = tsec->sid;
rcu_read_unlock();
if (!tsec)
return -EACCES;
return avc_has_perm(sid, SECINITSID_SECURITY,
SECCLASS_SECURITY, perms, NULL);
}
enum sel_inos {
SEL_ROOT_INO = 2,
SEL_LOAD, /* load policy */
SEL_ENFORCE, /* get or set enforcing status */
SEL_CONTEXT, /* validate context */
SEL_ACCESS, /* compute access decision */
SEL_CREATE, /* compute create labeling decision */
SEL_RELABEL, /* compute relabeling decision */
SEL_USER, /* compute reachable user contexts */
SEL_POLICYVERS, /* return policy version for this kernel */
SEL_COMMIT_BOOLS, /* commit new boolean values */
SEL_MLS, /* return if MLS policy is enabled */
SEL_DISABLE, /* disable SELinux until next reboot */
SEL_MEMBER, /* compute polyinstantiation membership decision */
SEL_CHECKREQPROT, /* check requested protection, not kernel-applied one */
SEL_COMPAT_NET, /* whether to use old compat network packet controls */
SEL_REJECT_UNKNOWN, /* export unknown reject handling to userspace */
SEL_DENY_UNKNOWN, /* export unknown deny handling to userspace */
SEL_INO_NEXT, /* The next inode number to use */
};
static unsigned long sel_last_ino = SEL_INO_NEXT - 1;
#define SEL_INITCON_INO_OFFSET 0x01000000
#define SEL_BOOL_INO_OFFSET 0x02000000
#define SEL_CLASS_INO_OFFSET 0x04000000
#define SEL_POLICYCAP_INO_OFFSET 0x08000000
#define SEL_INO_MASK 0x00ffffff
#define TMPBUFLEN 12
static ssize_t sel_read_enforce(struct file *filp, char __user *buf,
size_t count, loff_t *ppos)
{
char tmpbuf[TMPBUFLEN];
ssize_t length;
length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_enforcing);
return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
}
#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
static ssize_t sel_write_enforce(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
char *page;
ssize_t length;
int new_value;
if (count >= PAGE_SIZE)
return -ENOMEM;
if (*ppos != 0) {
/* No partial writes. */
return -EINVAL;
}
page = (char *)get_zeroed_page(GFP_KERNEL);
if (!page)
return -ENOMEM;
length = -EFAULT;
if (copy_from_user(page, buf, count))
goto out;
length = -EINVAL;
if (sscanf(page, "%d", &new_value) != 1)
goto out;
if (new_value != selinux_enforcing) {
length = task_has_security(current, SECURITY__SETENFORCE);
if (length)
goto out;
audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
"enforcing=%d old_enforcing=%d auid=%u ses=%u",
new_value, selinux_enforcing,
audit_get_loginuid(current),
audit_get_sessionid(current));
selinux_enforcing = new_value;
if (selinux_enforcing)
avc_ss_reset(0);
selnl_notify_setenforce(selinux_enforcing);
}
length = count;
out:
free_page((unsigned long) page);
return length;
}
#else
#define sel_write_enforce NULL
#endif
static const struct file_operations sel_enforce_ops = {
.read = sel_read_enforce,
.write = sel_write_enforce,
};
static ssize_t sel_read_handle_unknown(struct file *filp, char __user *buf,
size_t count, loff_t *ppos)
{
char tmpbuf[TMPBUFLEN];
ssize_t length;
ino_t ino = filp->f_path.dentry->d_inode->i_ino;
int handle_unknown = (ino == SEL_REJECT_UNKNOWN) ?
security_get_reject_unknown() : !security_get_allow_unknown();
length = scnprintf(tmpbuf, TMPBUFLEN, "%d", handle_unknown);
return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
}
static const struct file_operations sel_handle_unknown_ops = {
.read = sel_read_handle_unknown,
};
#ifdef CONFIG_SECURITY_SELINUX_DISABLE
static ssize_t sel_write_disable(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
char *page;
ssize_t length;
int new_value;
extern int selinux_disable(void);
if (count >= PAGE_SIZE)
return -ENOMEM;
if (*ppos != 0) {
/* No partial writes. */
return -EINVAL;
}
page = (char *)get_zeroed_page(GFP_KERNEL);
if (!page)
return -ENOMEM;
length = -EFAULT;
if (copy_from_user(page, buf, count))
goto out;
length = -EINVAL;
if (sscanf(page, "%d", &new_value) != 1)
goto out;
if (new_value) {
length = selinux_disable();
if (length < 0)
goto out;
audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
"selinux=0 auid=%u ses=%u",
audit_get_loginuid(current),
audit_get_sessionid(current));
}
length = count;
out:
free_page((unsigned long) page);
return length;
}
#else
#define sel_write_disable NULL
#endif
static const struct file_operations sel_disable_ops = {
.write = sel_write_disable,
};
static ssize_t sel_read_policyvers(struct file *filp, char __user *buf,
size_t count, loff_t *ppos)
{
char tmpbuf[TMPBUFLEN];
ssize_t length;
length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX);
return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
}
static const struct file_operations sel_policyvers_ops = {
.read = sel_read_policyvers,
};
/* declaration for sel_write_load */
static int sel_make_bools(void);
static int sel_make_classes(void);
static int sel_make_policycap(void);
/* declaration for sel_make_class_dirs */
static int sel_make_dir(struct inode *dir, struct dentry *dentry,
unsigned long *ino);
static ssize_t sel_read_mls(struct file *filp, char __user *buf,
size_t count, loff_t *ppos)
{
char tmpbuf[TMPBUFLEN];
ssize_t length;
length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_mls_enabled);
return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
}
static const struct file_operations sel_mls_ops = {
.read = sel_read_mls,
};
static ssize_t sel_write_load(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
int ret;
ssize_t length;
void *data = NULL;
mutex_lock(&sel_mutex);
length = task_has_security(current, SECURITY__LOAD_POLICY);
if (length)
goto out;
if (*ppos != 0) {
/* No partial writes. */
length = -EINVAL;
goto out;
}
if ((count > 64 * 1024 * 1024)
|| (data = vmalloc(count)) == NULL) {
length = -ENOMEM;
goto out;
}
length = -EFAULT;
if (copy_from_user(data, buf, count) != 0)
goto out;
length = security_load_policy(data, count);
if (length)
goto out;
ret = sel_make_bools();
if (ret) {
length = ret;
goto out1;
}
ret = sel_make_classes();
if (ret) {
length = ret;
goto out1;
}
ret = sel_make_policycap();
if (ret)
length = ret;
else
length = count;
out1:
audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_POLICY_LOAD,
"policy loaded auid=%u ses=%u",
audit_get_loginuid(current),
audit_get_sessionid(current));
out:
mutex_unlock(&sel_mutex);
vfree(data);
return length;
}
static const struct file_operations sel_load_ops = {
.write = sel_write_load,
};
static ssize_t sel_write_context(struct file *file, char *buf, size_t size)
{
char *canon;
u32 sid, len;
ssize_t length;
length = task_has_security(current, SECURITY__CHECK_CONTEXT);
if (length)
return length;
length = security_context_to_sid(buf, size, &sid);
if (length < 0)
return length;
length = security_sid_to_context(sid, &canon, &len);
if (length < 0)
return length;
if (len > SIMPLE_TRANSACTION_LIMIT) {
printk(KERN_ERR "SELinux: %s: context size (%u) exceeds "
"payload max\n", __func__, len);
length = -ERANGE;
goto out;
}
memcpy(buf, canon, len);
length = len;
out:
kfree(canon);
return length;
}
static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf,
size_t count, loff_t *ppos)
{
char tmpbuf[TMPBUFLEN];
ssize_t length;
length = scnprintf(tmpbuf, TMPBUFLEN, "%u", selinux_checkreqprot);
return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
}
static ssize_t sel_write_checkreqprot(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
char *page;
ssize_t length;
unsigned int new_value;
length = task_has_security(current, SECURITY__SETCHECKREQPROT);
if (length)
return length;
if (count >= PAGE_SIZE)
return -ENOMEM;
if (*ppos != 0) {
/* No partial writes. */
return -EINVAL;
}
page = (char *)get_zeroed_page(GFP_KERNEL);
if (!page)
return -ENOMEM;
length = -EFAULT;
if (copy_from_user(page, buf, count))
goto out;
length = -EINVAL;
if (sscanf(page, "%u", &new_value) != 1)
goto out;
selinux_checkreqprot = new_value ? 1 : 0;
length = count;
out:
free_page((unsigned long) page);
return length;
}
static const struct file_operations sel_checkreqprot_ops = {
.read = sel_read_checkreqprot,
.write = sel_write_checkreqprot,
};
/*
* Remaining nodes use transaction based IO methods like nfsd/nfsctl.c
*/
static ssize_t sel_write_access(struct file *file, char *buf, size_t size);
static ssize_t sel_write_create(struct file *file, char *buf, size_t size);
static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size);
static ssize_t sel_write_user(struct file *file, char *buf, size_t size);
static ssize_t sel_write_member(struct file *file, char *buf, size_t size);
static ssize_t (*write_op[])(struct file *, char *, size_t) = {
[SEL_ACCESS] = sel_write_access,
[SEL_CREATE] = sel_write_create,
[SEL_RELABEL] = sel_write_relabel,
[SEL_USER] = sel_write_user,
[SEL_MEMBER] = sel_write_member,
[SEL_CONTEXT] = sel_write_context,
};
static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
{
ino_t ino = file->f_path.dentry->d_inode->i_ino;
char *data;
ssize_t rv;
if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
return -EINVAL;
data = simple_transaction_get(file, buf, size);
if (IS_ERR(data))
return PTR_ERR(data);
rv = write_op[ino](file, data, size);
if (rv > 0) {
simple_transaction_set(file, rv);
rv = size;
}
return rv;
}
static const struct file_operations transaction_ops = {
.write = selinux_transaction_write,
.read = simple_transaction_read,
.release = simple_transaction_release,
};
/*
* payload - write methods
* If the method has a response, the response should be put in buf,
* and the length returned. Otherwise return 0 or and -error.
*/
static ssize_t sel_write_access(struct file *file, char *buf, size_t size)
{
char *scon, *tcon;
u32 ssid, tsid;
u16 tclass;
u32 req;
struct av_decision avd;
ssize_t length;
length = task_has_security(current, SECURITY__COMPUTE_AV);
if (length)
return length;
length = -ENOMEM;
scon = kzalloc(size+1, GFP_KERNEL);
if (!scon)
return length;
tcon = kzalloc(size+1, GFP_KERNEL);
if (!tcon)
goto out;
length = -EINVAL;
if (sscanf(buf, "%s %s %hu %x", scon, tcon, &tclass, &req) != 4)
goto out2;
length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
if (length < 0)
goto out2;
length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
if (length < 0)
goto out2;
length = security_compute_av(ssid, tsid, tclass, req, &avd);
if (length < 0)
goto out2;
length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
"%x %x %x %x %u %x",
avd.allowed, 0xffffffff,
avd.auditallow, avd.auditdeny,
avd.seqno, avd.flags);
out2:
kfree(tcon);
out:
kfree(scon);
return length;
}
static ssize_t sel_write_create(struct file *file, char *buf, size_t size)
{
char *scon, *tcon;
u32 ssid, tsid, newsid;
u16 tclass;
ssize_t length;
char *newcon;
u32 len;
length = task_has_security(current, SECURITY__COMPUTE_CREATE);
if (length)
return length;
length = -ENOMEM;
scon = kzalloc(size+1, GFP_KERNEL);
if (!scon)
return length;
tcon = kzalloc(size+1, GFP_KERNEL);
if (!tcon)
goto out;
length = -EINVAL;
if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
goto out2;
length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
if (length < 0)
goto out2;
length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
if (length < 0)
goto out2;
length = security_transition_sid(ssid, tsid, tclass, &newsid);
if (length < 0)
goto out2;
length = security_sid_to_context(newsid, &newcon, &len);
if (length < 0)
goto out2;
if (len > SIMPLE_TRANSACTION_LIMIT) {
printk(KERN_ERR "SELinux: %s: context size (%u) exceeds "
"payload max\n", __func__, len);
length = -ERANGE;
goto out3;
}
memcpy(buf, newcon, len);
length = len;
out3:
kfree(newcon);
out2:
kfree(tcon);
out:
kfree(scon);
return length;
}
static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size)
{
char *scon, *tcon;
u32 ssid, tsid, newsid;
u16 tclass;
ssize_t length;
char *newcon;
u32 len;
length = task_has_security(current, SECURITY__COMPUTE_RELABEL);
if (length)
return length;
length = -ENOMEM;
scon = kzalloc(size+1, GFP_KERNEL);
if (!scon)
return length;
tcon = kzalloc(size+1, GFP_KERNEL);
if (!tcon)
goto out;
length = -EINVAL;
if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
goto out2;
length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
if (length < 0)
goto out2;
length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
if (length < 0)
goto out2;
length = security_change_sid(ssid, tsid, tclass, &newsid);
if (length < 0)
goto out2;
length = security_sid_to_context(newsid, &newcon, &len);
if (length < 0)
goto out2;
if (len > SIMPLE_TRANSACTION_LIMIT) {
length = -ERANGE;
goto out3;
}
memcpy(buf, newcon, len);
length = len;
out3:
kfree(newcon);
out2:
kfree(tcon);
out:
kfree(scon);
return length;
}
static ssize_t sel_write_user(struct file *file, char *buf, size_t size)
{
char *con, *user, *ptr;
u32 sid, *sids;
ssize_t length;
char *newcon;
int i, rc;
u32 len, nsids;
length = task_has_security(current, SECURITY__COMPUTE_USER);
if (length)
return length;
length = -ENOMEM;
con = kzalloc(size+1, GFP_KERNEL);
if (!con)
return length;
user = kzalloc(size+1, GFP_KERNEL);
if (!user)
goto out;
length = -EINVAL;
if (sscanf(buf, "%s %s", con, user) != 2)
goto out2;
length = security_context_to_sid(con, strlen(con)+1, &sid);
if (length < 0)
goto out2;
length = security_get_user_sids(sid, user, &sids, &nsids);
if (length < 0)
goto out2;
length = sprintf(buf, "%u", nsids) + 1;
ptr = buf + length;
for (i = 0; i < nsids; i++) {
rc = security_sid_to_context(sids[i], &newcon, &len);
if (rc) {
length = rc;
goto out3;
}
if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
kfree(newcon);
length = -ERANGE;
goto out3;
}
memcpy(ptr, newcon, len);
kfree(newcon);
ptr += len;
length += len;
}
out3:
kfree(sids);
out2:
kfree(user);
out:
kfree(con);
return length;
}
static ssize_t sel_write_member(struct file *file, char *buf, size_t size)
{
char *scon, *tcon;
u32 ssid, tsid, newsid;
u16 tclass;
ssize_t length;
char *newcon;
u32 len;
length = task_has_security(current, SECURITY__COMPUTE_MEMBER);
if (length)
return length;
length = -ENOMEM;
scon = kzalloc(size+1, GFP_KERNEL);
if (!scon)
return length;
tcon = kzalloc(size+1, GFP_KERNEL);
if (!tcon)
goto out;
length = -EINVAL;
if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
goto out2;
length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
if (length < 0)
goto out2;
length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
if (length < 0)
goto out2;
length = security_member_sid(ssid, tsid, tclass, &newsid);
if (length < 0)
goto out2;
length = security_sid_to_context(newsid, &newcon, &len);
if (length < 0)
goto out2;
if (len > SIMPLE_TRANSACTION_LIMIT) {
printk(KERN_ERR "SELinux: %s: context size (%u) exceeds "
"payload max\n", __func__, len);
length = -ERANGE;
goto out3;
}
memcpy(buf, newcon, len);
length = len;
out3:
kfree(newcon);
out2:
kfree(tcon);
out:
kfree(scon);
return length;
}
static struct inode *sel_make_inode(struct super_block *sb, int mode)
{
struct inode *ret = new_inode(sb);
if (ret) {
ret->i_mode = mode;
ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
}
return ret;
}
static ssize_t sel_read_bool(struct file *filep, char __user *buf,
size_t count, loff_t *ppos)
{
char *page = NULL;
ssize_t length;
ssize_t ret;
int cur_enforcing;
struct inode *inode = filep->f_path.dentry->d_inode;
unsigned index = inode->i_ino & SEL_INO_MASK;
const char *name = filep->f_path.dentry->d_name.name;
mutex_lock(&sel_mutex);
if (index >= bool_num || strcmp(name, bool_pending_names[index])) {
ret = -EINVAL;
goto out;
}
page = (char *)get_zeroed_page(GFP_KERNEL);
if (!page) {
ret = -ENOMEM;
goto out;
}
cur_enforcing = security_get_bool_value(index);
if (cur_enforcing < 0) {
ret = cur_enforcing;
goto out;
}
length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
bool_pending_values[index]);
ret = simple_read_from_buffer(buf, count, ppos, page, length);
out:
mutex_unlock(&sel_mutex);
if (page)
free_page((unsigned long)page);
return ret;
}
static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
size_t count, loff_t *ppos)
{
char *page = NULL;
ssize_t length;
int new_value;
struct inode *inode = filep->f_path.dentry->d_inode;
unsigned index = inode->i_ino & SEL_INO_MASK;
const char *name = filep->f_path.dentry->d_name.name;
mutex_lock(&sel_mutex);
length = task_has_security(current, SECURITY__SETBOOL);
if (length)
goto out;
if (index >= bool_num || strcmp(name, bool_pending_names[index])) {
length = -EINVAL;
goto out;
}
if (count >= PAGE_SIZE) {
length = -ENOMEM;
goto out;
}
if (*ppos != 0) {
/* No partial writes. */
length = -EINVAL;
goto out;
}
page = (char *)get_zeroed_page(GFP_KERNEL);
if (!page) {
length = -ENOMEM;
goto out;
}
length = -EFAULT;
if (copy_from_user(page, buf, count))
goto out;
length = -EINVAL;
if (sscanf(page, "%d", &new_value) != 1)
goto out;
if (new_value)
new_value = 1;
bool_pending_values[index] = new_value;
length = count;
out:
mutex_unlock(&sel_mutex);
if (page)
free_page((unsigned long) page);
return length;
}
static const struct file_operations sel_bool_ops = {
.read = sel_read_bool,
.write = sel_write_bool,
};
static ssize_t sel_commit_bools_write(struct file *filep,
const char __user *buf,
size_t count, loff_t *ppos)
{
char *page = NULL;
ssize_t length;
int new_value;
mutex_lock(&sel_mutex);
length = task_has_security(current, SECURITY__SETBOOL);
if (length)
goto out;
if (count >= PAGE_SIZE) {
length = -ENOMEM;
goto out;
}
if (*ppos != 0) {
/* No partial writes. */
goto out;
}
page = (char *)get_zeroed_page(GFP_KERNEL);
if (!page) {
length = -ENOMEM;
goto out;
}
length = -EFAULT;
if (copy_from_user(page, buf, count))
goto out;
length = -EINVAL;
if (sscanf(page, "%d", &new_value) != 1)
goto out;
if (new_value && bool_pending_values)
security_set_bools(bool_num, bool_pending_values);
length = count;
out:
mutex_unlock(&sel_mutex);
if (page)
free_page((unsigned long) page);
return length;
}
static const struct file_operations sel_commit_bools_ops = {
.write = sel_commit_bools_write,
};
static void sel_remove_entries(struct dentry *de)
{
struct list_head *node;
spin_lock(&dcache_lock);
node = de->d_subdirs.next;
while (node != &de->d_subdirs) {
struct dentry *d = list_entry(node, struct dentry, d_u.d_child);
list_del_init(node);
if (d->d_inode) {
d = dget_locked(d);
spin_unlock(&dcache_lock);
d_delete(d);
simple_unlink(de->d_inode, d);
dput(d);
spin_lock(&dcache_lock);
}
node = de->d_subdirs.next;
}
spin_unlock(&dcache_lock);
}
#define BOOL_DIR_NAME "booleans"
static int sel_make_bools(void)
{
int i, ret = 0;
ssize_t len;
struct dentry *dentry = NULL;
struct dentry *dir = bool_dir;
struct inode *inode = NULL;
struct inode_security_struct *isec;
char **names = NULL, *page;
int num;
int *values = NULL;
u32 sid;
/* remove any existing files */
kfree(bool_pending_names);
kfree(bool_pending_values);
bool_pending_names = NULL;
bool_pending_values = NULL;
sel_remove_entries(dir);
page = (char *)get_zeroed_page(GFP_KERNEL);
if (!page)
return -ENOMEM;
ret = security_get_bools(&num, &names, &values);
if (ret != 0)
goto out;
for (i = 0; i < num; i++) {
dentry = d_alloc_name(dir, names[i]);
if (!dentry) {
ret = -ENOMEM;
goto err;
}
inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
if (!inode) {
ret = -ENOMEM;
goto err;
}
len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
if (len < 0) {
ret = -EINVAL;
goto err;
} else if (len >= PAGE_SIZE) {
ret = -ENAMETOOLONG;
goto err;
}
isec = (struct inode_security_struct *)inode->i_security;
ret = security_genfs_sid("selinuxfs", page, SECCLASS_FILE, &sid);
if (ret)
goto err;
isec->sid = sid;
isec->initialized = 1;
inode->i_fop = &sel_bool_ops;
inode->i_ino = i|SEL_BOOL_INO_OFFSET;
d_add(dentry, inode);
}
bool_num = num;
bool_pending_names = names;
bool_pending_values = values;
out:
free_page((unsigned long)page);
return ret;
err:
if (names) {
for (i = 0; i < num; i++)
kfree(names[i]);
kfree(names);
}
kfree(values);
sel_remove_entries(dir);
ret = -ENOMEM;
goto out;
}
#define NULL_FILE_NAME "null"
struct dentry *selinux_null;
static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
size_t count, loff_t *ppos)
{
char tmpbuf[TMPBUFLEN];
ssize_t length;
length = scnprintf(tmpbuf, TMPBUFLEN, "%u", avc_cache_threshold);
return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
}
static ssize_t sel_write_avc_cache_threshold(struct file *file,
const char __user *buf,
size_t count, loff_t *ppos)
{
char *page;
ssize_t ret;
int new_value;
if (count >= PAGE_SIZE) {
ret = -ENOMEM;
goto out;
}
if (*ppos != 0) {
/* No partial writes. */
ret = -EINVAL;
goto out;
}
page = (char *)get_zeroed_page(GFP_KERNEL);
if (!page) {
ret = -ENOMEM;
goto out;
}
if (copy_from_user(page, buf, count)) {
ret = -EFAULT;
goto out_free;
}
if (sscanf(page, "%u", &new_value) != 1) {
ret = -EINVAL;
goto out;
}
if (new_value != avc_cache_threshold) {
ret = task_has_security(current, SECURITY__SETSECPARAM);
if (ret)
goto out_free;
avc_cache_threshold = new_value;
}
ret = count;
out_free:
free_page((unsigned long)page);
out:
return ret;
}
static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
size_t count, loff_t *ppos)
{
char *page;
ssize_t ret = 0;
page = (char *)__get_free_page(GFP_KERNEL);
if (!page) {
ret = -ENOMEM;
goto out;
}
ret = avc_get_hash_stats(page);
if (ret >= 0)
ret = simple_read_from_buffer(buf, count, ppos, page, ret);
free_page((unsigned long)page);
out:
return ret;
}
static const struct file_operations sel_avc_cache_threshold_ops = {
.read = sel_read_avc_cache_threshold,
.write = sel_write_avc_cache_threshold,
};
static const struct file_operations sel_avc_hash_stats_ops = {
.read = sel_read_avc_hash_stats,
};
#ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
{
int cpu;
for (cpu = *idx; cpu < nr_cpu_ids; ++cpu) {
if (!cpu_possible(cpu))
continue;
*idx = cpu + 1;
return &per_cpu(avc_cache_stats, cpu);
}
return NULL;
}
static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
{
loff_t n = *pos - 1;
if (*pos == 0)
return SEQ_START_TOKEN;
return sel_avc_get_stat_idx(&n);
}
static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
return sel_avc_get_stat_idx(pos);
}
static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
{
struct avc_cache_stats *st = v;
if (v == SEQ_START_TOKEN)
seq_printf(seq, "lookups hits misses allocations reclaims "
"frees\n");
else
seq_printf(seq, "%u %u %u %u %u %u\n", st->lookups,
st->hits, st->misses, st->allocations,
st->reclaims, st->frees);
return 0;
}
static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
{ }
static const struct seq_operations sel_avc_cache_stats_seq_ops = {
.start = sel_avc_stats_seq_start,
.next = sel_avc_stats_seq_next,
.show = sel_avc_stats_seq_show,
.stop = sel_avc_stats_seq_stop,
};
static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
{
return seq_open(file, &sel_avc_cache_stats_seq_ops);
}
static const struct file_operations sel_avc_cache_stats_ops = {
.open = sel_open_avc_cache_stats,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
};
#endif
static int sel_make_avc_files(struct dentry *dir)
{
int i, ret = 0;
static struct tree_descr files[] = {
{ "cache_threshold",
&sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
{ "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
#ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
{ "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
#endif
};
for (i = 0; i < ARRAY_SIZE(files); i++) {
struct inode *inode;
struct dentry *dentry;
dentry = d_alloc_name(dir, files[i].name);
if (!dentry) {
ret = -ENOMEM;
goto out;
}
inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
if (!inode) {
ret = -ENOMEM;
goto out;
}
inode->i_fop = files[i].ops;
inode->i_ino = ++sel_last_ino;
d_add(dentry, inode);
}
out:
return ret;
}
static ssize_t sel_read_initcon(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
struct inode *inode;
char *con;
u32 sid, len;
ssize_t ret;
inode = file->f_path.dentry->d_inode;
sid = inode->i_ino&SEL_INO_MASK;
ret = security_sid_to_context(sid, &con, &len);
if (ret < 0)
return ret;
ret = simple_read_from_buffer(buf, count, ppos, con, len);
kfree(con);
return ret;
}
static const struct file_operations sel_initcon_ops = {
.read = sel_read_initcon,
};
static int sel_make_initcon_files(struct dentry *dir)
{
int i, ret = 0;
for (i = 1; i <= SECINITSID_NUM; i++) {
struct inode *inode;
struct dentry *dentry;
dentry = d_alloc_name(dir, security_get_initial_sid_context(i));
if (!dentry) {
ret = -ENOMEM;
goto out;
}
inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
if (!inode) {
ret = -ENOMEM;
goto out;
}
inode->i_fop = &sel_initcon_ops;
inode->i_ino = i|SEL_INITCON_INO_OFFSET;
d_add(dentry, inode);
}
out:
return ret;
}
static inline unsigned int sel_div(unsigned long a, unsigned long b)
{
return a / b - (a % b < 0);
}
static inline unsigned long sel_class_to_ino(u16 class)
{
return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET;
}
static inline u16 sel_ino_to_class(unsigned long ino)
{
return sel_div(ino & SEL_INO_MASK, SEL_VEC_MAX + 1);
}
static inline unsigned long sel_perm_to_ino(u16 class, u32 perm)
{
return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET;
}
static inline u32 sel_ino_to_perm(unsigned long ino)
{
return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1);
}
static ssize_t sel_read_class(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
ssize_t rc, len;
char *page;
unsigned long ino = file->f_path.dentry->d_inode->i_ino;
page = (char *)__get_free_page(GFP_KERNEL);
if (!page) {
rc = -ENOMEM;
goto out;
}
len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_class(ino));
rc = simple_read_from_buffer(buf, count, ppos, page, len);
free_page((unsigned long)page);
out:
return rc;
}
static const struct file_operations sel_class_ops = {
.read = sel_read_class,
};
static ssize_t sel_read_perm(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
ssize_t rc, len;
char *page;
unsigned long ino = file->f_path.dentry->d_inode->i_ino;
page = (char *)__get_free_page(GFP_KERNEL);
if (!page) {
rc = -ENOMEM;
goto out;
}
len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_perm(ino));
rc = simple_read_from_buffer(buf, count, ppos, page, len);
free_page((unsigned long)page);
out:
return rc;
}
static const struct file_operations sel_perm_ops = {
.read = sel_read_perm,
};
static ssize_t sel_read_policycap(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
int value;
char tmpbuf[TMPBUFLEN];
ssize_t length;
unsigned long i_ino = file->f_path.dentry->d_inode->i_ino;
value = security_policycap_supported(i_ino & SEL_INO_MASK);
length = scnprintf(tmpbuf, TMPBUFLEN, "%d", value);
return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
}
static const struct file_operations sel_policycap_ops = {
.read = sel_read_policycap,
};
static int sel_make_perm_files(char *objclass, int classvalue,
struct dentry *dir)
{
int i, rc = 0, nperms;
char **perms;
rc = security_get_permissions(objclass, &perms, &nperms);
if (rc)
goto out;
for (i = 0; i < nperms; i++) {
struct inode *inode;
struct dentry *dentry;
dentry = d_alloc_name(dir, perms[i]);
if (!dentry) {
rc = -ENOMEM;
goto out1;
}
inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
if (!inode) {
rc = -ENOMEM;
goto out1;
}
inode->i_fop = &sel_perm_ops;
/* i+1 since perm values are 1-indexed */
inode->i_ino = sel_perm_to_ino(classvalue, i+1);
d_add(dentry, inode);
}
out1:
for (i = 0; i < nperms; i++)
kfree(perms[i]);
kfree(perms);
out:
return rc;
}
static int sel_make_class_dir_entries(char *classname, int index,
struct dentry *dir)
{
struct dentry *dentry = NULL;
struct inode *inode = NULL;
int rc;
dentry = d_alloc_name(dir, "index");
if (!dentry) {
rc = -ENOMEM;
goto out;
}
inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
if (!inode) {
rc = -ENOMEM;
goto out;
}
inode->i_fop = &sel_class_ops;
inode->i_ino = sel_class_to_ino(index);
d_add(dentry, inode);
dentry = d_alloc_name(dir, "perms");
if (!dentry) {
rc = -ENOMEM;
goto out;
}
rc = sel_make_dir(dir->d_inode, dentry, &last_class_ino);
if (rc)
goto out;
rc = sel_make_perm_files(classname, index, dentry);
out:
return rc;
}
static void sel_remove_classes(void)
{
struct list_head *class_node;
list_for_each(class_node, &class_dir->d_subdirs) {
struct dentry *class_subdir = list_entry(class_node,
struct dentry, d_u.d_child);
struct list_head *class_subdir_node;
list_for_each(class_subdir_node, &class_subdir->d_subdirs) {
struct dentry *d = list_entry(class_subdir_node,
struct dentry, d_u.d_child);
if (d->d_inode)
if (d->d_inode->i_mode & S_IFDIR)
sel_remove_entries(d);
}
sel_remove_entries(class_subdir);
}
sel_remove_entries(class_dir);
}
static int sel_make_classes(void)
{
int rc = 0, nclasses, i;
char **classes;
/* delete any existing entries */
sel_remove_classes();
rc = security_get_classes(&classes, &nclasses);
if (rc < 0)
goto out;
/* +2 since classes are 1-indexed */
last_class_ino = sel_class_to_ino(nclasses+2);
for (i = 0; i < nclasses; i++) {
struct dentry *class_name_dir;
class_name_dir = d_alloc_name(class_dir, classes[i]);
if (!class_name_dir) {
rc = -ENOMEM;
goto out1;
}
rc = sel_make_dir(class_dir->d_inode, class_name_dir,
&last_class_ino);
if (rc)
goto out1;
/* i+1 since class values are 1-indexed */
rc = sel_make_class_dir_entries(classes[i], i+1,
class_name_dir);
if (rc)
goto out1;
}
out1:
for (i = 0; i < nclasses; i++)
kfree(classes[i]);
kfree(classes);
out:
return rc;
}
static int sel_make_policycap(void)
{
unsigned int iter;
struct dentry *dentry = NULL;
struct inode *inode = NULL;
sel_remove_entries(policycap_dir);
for (iter = 0; iter <= POLICYDB_CAPABILITY_MAX; iter++) {
if (iter < ARRAY_SIZE(policycap_names))
dentry = d_alloc_name(policycap_dir,
policycap_names[iter]);
else
dentry = d_alloc_name(policycap_dir, "unknown");
if (dentry == NULL)
return -ENOMEM;
inode = sel_make_inode(policycap_dir->d_sb, S_IFREG | S_IRUGO);
if (inode == NULL)
return -ENOMEM;
inode->i_fop = &sel_policycap_ops;
inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET;
d_add(dentry, inode);
}
return 0;
}
static int sel_make_dir(struct inode *dir, struct dentry *dentry,
unsigned long *ino)
{
int ret = 0;
struct inode *inode;
inode = sel_make_inode(dir->i_sb, S_IFDIR | S_IRUGO | S_IXUGO);
if (!inode) {
ret = -ENOMEM;
goto out;
}
inode->i_op = &simple_dir_inode_operations;
inode->i_fop = &simple_dir_operations;
inode->i_ino = ++(*ino);
/* directory inodes start off with i_nlink == 2 (for "." entry) */
inc_nlink(inode);
d_add(dentry, inode);
/* bump link count on parent directory, too */
inc_nlink(dir);
out:
return ret;
}
static int sel_fill_super(struct super_block *sb, void *data, int silent)
{
int ret;
struct dentry *dentry;
struct inode *inode, *root_inode;
struct inode_security_struct *isec;
static struct tree_descr selinux_files[] = {
[SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
[SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR},
[SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO},
[SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO},
[SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO},
[SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO},
[SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO},
[SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO},
[SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR},
[SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO},
[SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR},
[SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO},
[SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
[SEL_REJECT_UNKNOWN] = {"reject_unknown", &sel_handle_unknown_ops, S_IRUGO},
[SEL_DENY_UNKNOWN] = {"deny_unknown", &sel_handle_unknown_ops, S_IRUGO},
/* last one */ {""}
};
ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
if (ret)
goto err;
root_inode = sb->s_root->d_inode;
dentry = d_alloc_name(sb->s_root, BOOL_DIR_NAME);
if (!dentry) {
ret = -ENOMEM;
goto err;
}
ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
if (ret)
goto err;
bool_dir = dentry;
dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
if (!dentry) {
ret = -ENOMEM;
goto err;
}
inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
if (!inode) {
ret = -ENOMEM;
goto err;
}
inode->i_ino = ++sel_last_ino;
isec = (struct inode_security_struct *)inode->i_security;
isec->sid = SECINITSID_DEVNULL;
isec->sclass = SECCLASS_CHR_FILE;
isec->initialized = 1;
init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
d_add(dentry, inode);
selinux_null = dentry;
dentry = d_alloc_name(sb->s_root, "avc");
if (!dentry) {
ret = -ENOMEM;
goto err;
}
ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
if (ret)
goto err;
ret = sel_make_avc_files(dentry);
if (ret)
goto err;
dentry = d_alloc_name(sb->s_root, "initial_contexts");
if (!dentry) {
ret = -ENOMEM;
goto err;
}
ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
if (ret)
goto err;
ret = sel_make_initcon_files(dentry);
if (ret)
goto err;
dentry = d_alloc_name(sb->s_root, "class");
if (!dentry) {
ret = -ENOMEM;
goto err;
}
ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
if (ret)
goto err;
class_dir = dentry;
dentry = d_alloc_name(sb->s_root, "policy_capabilities");
if (!dentry) {
ret = -ENOMEM;
goto err;
}
ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
if (ret)
goto err;
policycap_dir = dentry;
out:
return ret;
err:
printk(KERN_ERR "SELinux: %s: failed while creating inodes\n",
__func__);
goto out;
}
static int sel_get_sb(struct file_system_type *fs_type,
int flags, const char *dev_name, void *data,
struct vfsmount *mnt)
{
return get_sb_single(fs_type, flags, data, sel_fill_super, mnt);
}
static struct file_system_type sel_fs_type = {
.name = "selinuxfs",
.get_sb = sel_get_sb,
.kill_sb = kill_litter_super,
};
struct vfsmount *selinuxfs_mount;
static int __init init_sel_fs(void)
{
int err;
if (!selinux_enabled)
return 0;
err = register_filesystem(&sel_fs_type);
if (!err) {
selinuxfs_mount = kern_mount(&sel_fs_type);
if (IS_ERR(selinuxfs_mount)) {
printk(KERN_ERR "selinuxfs: could not mount!\n");
err = PTR_ERR(selinuxfs_mount);
selinuxfs_mount = NULL;
}
}
return err;
}
__initcall(init_sel_fs);
#ifdef CONFIG_SECURITY_SELINUX_DISABLE
void exit_sel_fs(void)
{
unregister_filesystem(&sel_fs_type);
}
#endif
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