android_kernel_xiaomi_sm8350/security/selinux/selinuxfs.c
James Carter f0ee2e467f selinux: export initial SID contexts via selinuxfs
Make the initial SID contexts accessible to userspace via selinuxfs.
An initial use of this support will be to make the unlabeled context
available to libselinux for use for invalidated userspace SIDs.

Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
Acked-by:  Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
2007-04-26 01:36:00 -04:00

1454 lines
32 KiB
C

/* Updated: Karl MacMillan <kmacmillan@tresys.com>
*
* Added conditional policy language extensions
*
* 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 <asm/uaccess.h>
#include <asm/semaphore.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"
unsigned int selinux_checkreqprot = CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
#ifdef CONFIG_SECURITY_SELINUX_ENABLE_SECMARK_DEFAULT
#define SELINUX_COMPAT_NET_VALUE 0
#else
#define SELINUX_COMPAT_NET_VALUE 1
#endif
int selinux_compat_net = SELINUX_COMPAT_NET_VALUE;
static int __init checkreqprot_setup(char *str)
{
selinux_checkreqprot = simple_strtoul(str,NULL,0) ? 1 : 0;
return 1;
}
__setup("checkreqprot=", checkreqprot_setup);
static int __init selinux_compat_net_setup(char *str)
{
selinux_compat_net = simple_strtoul(str,NULL,0) ? 1 : 0;
return 1;
}
__setup("selinux_compat_net=", selinux_compat_net_setup);
static DEFINE_MUTEX(sel_mutex);
/* global data for booleans */
static struct dentry *bool_dir = NULL;
static int bool_num = 0;
static int *bool_pending_values = NULL;
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)
{
struct task_security_struct *tsec;
tsec = tsk->security;
if (!tsec)
return -EACCES;
return avc_has_perm(tsec->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_AVC, /* AVC management directory */
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 */
};
#define SEL_INITCON_INO_OFFSET 0x01000000
#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", new_value,
selinux_enforcing,
audit_get_loginuid(current->audit_context));
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,
};
#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",
audit_get_loginuid(current->audit_context));
}
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 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;
else
length = count;
audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_POLICY_LOAD,
"policy loaded auid=%u",
audit_get_loginuid(current->audit_context));
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 "%s: context size (%u) exceeds payload "
"max\n", __FUNCTION__, 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,
};
static ssize_t sel_read_compat_net(struct file *filp, char __user *buf,
size_t count, loff_t *ppos)
{
char tmpbuf[TMPBUFLEN];
ssize_t length;
length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_compat_net);
return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
}
static ssize_t sel_write_compat_net(struct file * file, const char __user * buf,
size_t count, loff_t *ppos)
{
char *page;
ssize_t length;
int new_value;
length = task_has_security(current, SECURITY__LOAD_POLICY);
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, "%d", &new_value) != 1)
goto out;
selinux_compat_net = new_value ? 1 : 0;
length = count;
out:
free_page((unsigned long) page);
return length;
}
static const struct file_operations sel_compat_net_ops = {
.read = sel_read_compat_net,
.write = sel_write_compat_net,
};
/*
* 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",
avd.allowed, avd.decided,
avd.auditallow, avd.auditdeny,
avd.seqno);
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 "%s: context size (%u) exceeds payload "
"max\n", __FUNCTION__, 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 "%s: context size (%u) exceeds payload "
"max\n", __FUNCTION__, 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_uid = ret->i_gid = 0;
ret->i_blocks = 0;
ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
}
return ret;
}
#define BOOL_INO_OFFSET 30
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;
mutex_lock(&sel_mutex);
ret = -EFAULT;
/* check to see if this file has been deleted */
if (!filep->f_op)
goto out;
if (count > PAGE_SIZE) {
ret = -EINVAL;
goto out;
}
if (!(page = (char*)get_zeroed_page(GFP_KERNEL))) {
ret = -ENOMEM;
goto out;
}
inode = filep->f_path.dentry->d_inode;
cur_enforcing = security_get_bool_value(inode->i_ino - BOOL_INO_OFFSET);
if (cur_enforcing < 0) {
ret = cur_enforcing;
goto out;
}
length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
bool_pending_values[inode->i_ino - BOOL_INO_OFFSET]);
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 = -EFAULT;
int new_value;
struct inode *inode;
mutex_lock(&sel_mutex);
length = task_has_security(current, SECURITY__SETBOOL);
if (length)
goto out;
/* check to see if this file has been deleted */
if (!filep->f_op)
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;
}
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;
inode = filep->f_path.dentry->d_inode;
bool_pending_values[inode->i_ino - BOOL_INO_OFFSET] = 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 = -EFAULT;
int new_value;
mutex_lock(&sel_mutex);
length = task_has_security(current, SECURITY__SETBOOL);
if (length)
goto out;
/* check to see if this file has been deleted */
if (!filep->f_op)
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;
}
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,
};
/* delete booleans - partial revoke() from
* fs/proc/generic.c proc_kill_inodes */
static void sel_remove_bools(struct dentry *de)
{
struct list_head *p, *node;
struct super_block *sb = de->d_sb;
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);
file_list_lock();
list_for_each(p, &sb->s_files) {
struct file * filp = list_entry(p, struct file, f_u.fu_list);
struct dentry * dentry = filp->f_path.dentry;
if (dentry->d_parent != de) {
continue;
}
filp->f_op = NULL;
}
file_list_unlock();
}
#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_values);
bool_pending_values = NULL;
sel_remove_bools(dir);
if (!(page = (char*)get_zeroed_page(GFP_KERNEL)))
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;
if ((ret = security_genfs_sid("selinuxfs", page, SECCLASS_FILE, &sid)))
goto err;
isec->sid = sid;
isec->initialized = 1;
inode->i_fop = &sel_bool_ops;
inode->i_ino = i + BOOL_INO_OFFSET;
d_add(dentry, inode);
}
bool_num = num;
bool_pending_values = values;
out:
free_page((unsigned long)page);
if (names) {
for (i = 0; i < num; i++)
kfree(names[i]);
kfree(names);
}
return ret;
err:
kfree(values);
sel_remove_bools(dir);
ret = -ENOMEM;
goto out;
}
#define NULL_FILE_NAME "null"
struct dentry *selinux_null = 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_CPUS; ++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 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;
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 int sel_make_dir(struct inode *dir, struct dentry *dentry)
{
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;
/* 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_COMPAT_NET] = {"compat_net", &sel_compat_net_ops, S_IRUGO|S_IWUSR},
/* 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);
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;
}
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);
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);
if (ret)
goto err;
ret = sel_make_initcon_files(dentry);
if (ret)
goto err;
out:
return ret;
err:
printk(KERN_ERR "%s: failed while creating inodes\n", __FUNCTION__);
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