// SPDX-License-Identifier: GPL-2.0-only
/* Updated: Karl MacMillan <[email protected]>
*
* Added conditional policy language extensions
*
* Updated: Hewlett-Packard <[email protected]>
*
* 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 <[email protected]>
*/
#include <linux/kernel.h>
#include <linux/pagemap.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/fs.h>
#include <linux/fs_context.h>
#include <linux/mount.h>
#include <linux/mutex.h>
#include <linux/namei.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>
#include <linux/kobject.h>
#include <linux/ctype.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"
#include "ima.h"
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_STATUS, /* export current status using mmap() */
SEL_POLICY, /* allow userspace to read the in kernel policy */
SEL_VALIDATE_TRANS, /* compute validatetrans decision */
SEL_INO_NEXT, /* The next inode number to use */
};
struct selinux_fs_info {
struct dentry *bool_dir;
unsigned int bool_num;
char **bool_pending_names;
int *bool_pending_values;
struct dentry *class_dir;
unsigned long last_class_ino;
bool policy_opened;
struct dentry *policycap_dir;
unsigned long last_ino;
struct super_block *sb;
};
static int selinux_fs_info_create(struct super_block *sb)
{
struct selinux_fs_info *fsi;
fsi = kzalloc(sizeof(*fsi), GFP_KERNEL);
if (!fsi)
return -ENOMEM;
fsi->last_ino = SEL_INO_NEXT - 1;
fsi->sb = sb;
sb->s_fs_info = fsi;
return 0;
}
static void selinux_fs_info_free(struct super_block *sb)
{
struct selinux_fs_info *fsi = sb->s_fs_info;
unsigned int i;
if (fsi) {
for (i = 0; i < fsi->bool_num; i++)
kfree(fsi->bool_pending_names[i]);
kfree(fsi->bool_pending_names);
kfree(fsi->bool_pending_values);
}
kfree(sb->s_fs_info);
sb->s_fs_info = NULL;
}
#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 BOOL_DIR_NAME "booleans"
#define CLASS_DIR_NAME "class"
#define POLICYCAP_DIR_NAME "policy_capabilities"
#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",
enforcing_enabled());
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 = NULL;
ssize_t length;
int scan_value;
bool old_value, new_value;
if (count >= PAGE_SIZE)
return -ENOMEM;
/* No partial writes. */
if (*ppos != 0)
return -EINVAL;
page = memdup_user_nul(buf, count);
if (IS_ERR(page))
return PTR_ERR(page);
length = -EINVAL;
if (sscanf(page, "%d", &scan_value) != 1)
goto out;
new_value = !!scan_value;
old_value = enforcing_enabled();
if (new_value != old_value) {
length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
SECCLASS_SECURITY, SECURITY__SETENFORCE,
NULL);
if (length)
goto out;
audit_log(audit_context(), GFP_KERNEL, AUDIT_MAC_STATUS,
"enforcing=%d old_enforcing=%d auid=%u ses=%u"
" enabled=1 old-enabled=1 lsm=selinux res=1",
new_value, old_value,
from_kuid(&init_user_ns, audit_get_loginuid(current)),
audit_get_sessionid(current));
enforcing_set(new_value);
if (new_value)
avc_ss_reset(0);
selnl_notify_setenforce(new_value);
selinux_status_update_setenforce(new_value);
if (!new_value)
call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL);
selinux_ima_measure_state();
}
length = count;
out:
kfree(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,
.llseek = generic_file_llseek,
};
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 = file_inode(filp)->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,
.llseek = generic_file_llseek,
};
static int sel_open_handle_status(struct inode *inode, struct file *filp)
{
struct page *status = selinux_kernel_status_page();
if (!status)
return -ENOMEM;
filp->private_data = status;
return 0;
}
static ssize_t sel_read_handle_status(struct file *filp, char __user *buf,
size_t count, loff_t *ppos)
{
struct page *status = filp->private_data;
BUG_ON(!status);
return simple_read_from_buffer(buf, count, ppos,
page_address(status),
sizeof(struct selinux_kernel_status));
}
static int sel_mmap_handle_status(struct file *filp,
struct vm_area_struct *vma)
{
struct page *status = filp->private_data;
unsigned long size = vma->vm_end - vma->vm_start;
BUG_ON(!status);
/* only allows one page from the head */
if (vma->vm_pgoff > 0 || size != PAGE_SIZE)
return -EIO;
/* disallow writable mapping */
if (vma->vm_flags & VM_WRITE)
return -EPERM;
/* disallow mprotect() turns it into writable */
vm_flags_clear(vma, VM_MAYWRITE);
return remap_pfn_range(vma, vma->vm_start,
page_to_pfn(status),
size, vma->vm_page_prot);
}
static const struct file_operations sel_handle_status_ops = {
.open = sel_open_handle_status,
.read = sel_read_handle_status,
.mmap = sel_mmap_handle_status,
.llseek = generic_file_llseek,
};
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;
if (count >= PAGE_SIZE)
return -ENOMEM;
/* No partial writes. */
if (*ppos != 0)
return -EINVAL;
page = memdup_user_nul(buf, count);
if (IS_ERR(page))
return PTR_ERR(page);
if (sscanf(page, "%d", &new_value) != 1) {
length = -EINVAL;
goto out;
}
length = count;
if (new_value) {
pr_err("SELinux: https://github.com/SELinuxProject/selinux-kernel/wiki/DEPRECATE-runtime-disable\n");
pr_err("SELinux: Runtime disable is not supported, use selinux=0 on the kernel cmdline.\n");
}
out:
kfree(page);
return length;
}
static const struct file_operations sel_disable_ops = {
.write = sel_write_disable,
.llseek = generic_file_llseek,
};
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,
.llseek = generic_file_llseek,
};
/* declaration for sel_write_load */
static int sel_make_bools(struct selinux_policy *newpolicy, struct dentry *bool_dir,
unsigned int *bool_num, char ***bool_pending_names,
int **bool_pending_values);
static int sel_make_classes(struct selinux_policy *newpolicy,
struct dentry *class_dir,
unsigned long *last_class_ino);
/* declaration for sel_make_class_dirs */
static struct dentry *sel_make_dir(struct dentry *dir, const char *name,
unsigned long *ino);
/* declaration for sel_make_policy_nodes */
static struct dentry *sel_make_swapover_dir(struct super_block *sb,
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",
security_mls_enabled());
return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
}
static const struct file_operations sel_mls_ops = {
.read = sel_read_mls,
.llseek = generic_file_llseek,
};
struct policy_load_memory {
size_t len;
void *data;
};
static int sel_open_policy(struct inode *inode, struct file *filp)
{
struct selinux_fs_info *fsi = inode->i_sb->s_fs_info;
struct policy_load_memory *plm = NULL;
int rc;
BUG_ON(filp->private_data);
mutex_lock(&selinux_state.policy_mutex);
rc = avc_has_perm(current_sid(), SECINITSID_SECURITY,
SECCLASS_SECURITY, SECURITY__READ_POLICY, NULL);
if (rc)
goto err;
rc = -EBUSY;
if (fsi->policy_opened)
goto err;
rc = -ENOMEM;
plm = kzalloc(sizeof(*plm), GFP_KERNEL);
if (!plm)
goto err;
rc = security_read_policy(&plm->data, &plm->len);
if (rc)
goto err;
if ((size_t)i_size_read(inode) != plm->len) {
inode_lock(inode);
i_size_write(inode, plm->len);
inode_unlock(inode);
}
fsi->policy_opened = 1;
filp->private_data = plm;
mutex_unlock(&selinux_state.policy_mutex);
return 0;
err:
mutex_unlock(&selinux_state.policy_mutex);
if (plm)
vfree(plm->data);
kfree(plm);
return rc;
}
static int sel_release_policy(struct inode *inode, struct file *filp)
{
struct selinux_fs_info *fsi = inode->i_sb->s_fs_info;
struct policy_load_memory *plm = filp->private_data;
BUG_ON(!plm);
fsi->policy_opened = 0;
vfree(plm->data);
kfree(plm);
return 0;
}
static ssize_t sel_read_policy(struct file *filp, char __user *buf,
size_t count, loff_t *ppos)
{
struct policy_load_memory *plm = filp->private_data;
int ret;
ret = avc_has_perm(current_sid(), SECINITSID_SECURITY,
SECCLASS_SECURITY, SECURITY__READ_POLICY, NULL);
if (ret)
return ret;
return simple_read_from_buffer(buf, count, ppos, plm->data, plm->len);
}
static vm_fault_t sel_mmap_policy_fault(struct vm_fault *vmf)
{
struct policy_load_memory *plm = vmf->vma->vm_file->private_data;
unsigned long offset;
struct page *page;
if (vmf->flags & (FAULT_FLAG_MKWRITE | FAULT_FLAG_WRITE))
return VM_FAULT_SIGBUS;
offset = vmf->pgoff << PAGE_SHIFT;
if (offset >= roundup(plm->len, PAGE_SIZE))
return VM_FAULT_SIGBUS;
page = vmalloc_to_page(plm->data + offset);
get_page(page);
vmf->page = page;
return 0;
}
static const struct vm_operations_struct sel_mmap_policy_ops = {
.fault = sel_mmap_policy_fault,
.page_mkwrite = sel_mmap_policy_fault,
};
static int sel_mmap_policy(struct file *filp, struct vm_area_struct *vma)
{
if (vma->vm_flags & VM_SHARED) {
/* do not allow mprotect to make mapping writable */
vm_flags_clear(vma, VM_MAYWRITE);
if (vma->vm_flags & VM_WRITE)
return -EACCES;
}
vm_flags_set(vma, VM_DONTEXPAND | VM_DONTDUMP);
vma->vm_ops = &sel_mmap_policy_ops;
return 0;
}
static const struct file_operations sel_policy_ops = {
.open = sel_open_policy,
.read = sel_read_policy,
.mmap = sel_mmap_policy,
.release = sel_release_policy,
.llseek = generic_file_llseek,
};
static void sel_remove_old_bool_data(unsigned int bool_num, char **bool_names,
int *bool_values)
{
u32 i;
/* bool_dir cleanup */
for (i = 0; i < bool_num; i++)
kfree(bool_names[i]);
kfree(bool_names);
kfree(bool_values);
}
static int sel_make_policy_nodes(struct selinux_fs_info *fsi,
struct selinux_policy *newpolicy)
{
int ret = 0;
struct dentry *tmp_parent, *tmp_bool_dir, *tmp_class_dir;
unsigned int bool_num = 0;
char **bool_names = NULL;
int *bool_values = NULL;
unsigned long tmp_ino = fsi->last_ino; /* Don't increment last_ino in this function */
tmp_parent = sel_make_swapover_dir(fsi->sb, &tmp_ino);
if (IS_ERR(tmp_parent))
return PTR_ERR(tmp_parent);
tmp_ino = fsi->bool_dir->d_inode->i_ino - 1; /* sel_make_dir will increment and set */
tmp_bool_dir = sel_make_dir(tmp_parent, BOOL_DIR_NAME, &tmp_ino);
if (IS_ERR(tmp_bool_dir)) {
ret = PTR_ERR(tmp_bool_dir);
goto out;
}
tmp_ino = fsi->class_dir->d_inode->i_ino - 1; /* sel_make_dir will increment and set */
tmp_class_dir = sel_make_dir(tmp_parent, CLASS_DIR_NAME, &tmp_ino);
if (IS_ERR(tmp_class_dir)) {
ret = PTR_ERR(tmp_class_dir);
goto out;
}
ret = sel_make_bools(newpolicy, tmp_bool_dir, &bool_num,
&bool_names, &bool_values);
if (ret)
goto out;
ret = sel_make_classes(newpolicy, tmp_class_dir,
&fsi->last_class_ino);
if (ret)
goto out;
lock_rename(tmp_parent, fsi->sb->s_root);
/* booleans */
d_exchange(tmp_bool_dir, fsi->bool_dir);
swap(fsi->bool_num, bool_num);
swap(fsi->bool_pending_names, bool_names);
swap(fsi->bool_pending_values, bool_values);
fsi->bool_dir = tmp_bool_dir;
/* classes */
d_exchange(tmp_class_dir, fsi->class_dir);
fsi->class_dir = tmp_class_dir;
unlock_rename(tmp_parent, fsi->sb->s_root);
out:
sel_remove_old_bool_data(bool_num, bool_names, bool_values);
/* Since the other temporary dirs are children of tmp_parent
* this will handle all the cleanup in the case of a failure before
* the swapover
*/
simple_recursive_removal(tmp_parent, NULL);
return ret;
}
static ssize_t sel_write_load(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
struct selinux_fs_info *fsi;
struct selinux_load_state load_state;
ssize_t length;
void *data = NULL;
/* no partial writes */
if (*ppos)
return -EINVAL;
/* no empty policies */
if (!count)
return -EINVAL;
mutex_lock(&selinux_state.policy_mutex);
length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
SECCLASS_SECURITY, SECURITY__LOAD_POLICY, NULL);
if (length)
goto out;
data = vmalloc(count);
if (!data) {
length = -ENOMEM;
goto out;
}
if (copy_from_user(data, buf, count) != 0) {
length = -EFAULT;
goto out;
}
length = security_load_policy(data, count, &load_state);
if (length) {
pr_warn_ratelimited("SELinux: failed to load policy\n");
goto out;
}
fsi = file_inode(file)->i_sb->s_fs_info;
length = sel_make_policy_nodes(fsi, load_state.policy);
if (length) {
pr_warn_ratelimited("SELinux: failed to initialize selinuxfs\n");
selinux_policy_cancel(&load_state);
goto out;
}
selinux_policy_commit(&load_state);
length = count;
audit_log(audit_context(), GFP_KERNEL, AUDIT_MAC_POLICY_LOAD,
"auid=%u ses=%u lsm=selinux res=1",
from_kuid(&init_user_ns, audit_get_loginuid(current)),
audit_get_sessionid(current));
out:
mutex_unlock(&selinux_state.policy_mutex);
vfree(data);
return length;
}
static const struct file_operations sel_load_ops = {
.write = sel_write_load,
.llseek = generic_file_llseek,
};
static ssize_t sel_write_context(struct file *file, char *buf, size_t size)
{
char *canon = NULL;
u32 sid, len;
ssize_t length;
length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
SECCLASS_SECURITY, SECURITY__CHECK_CONTEXT, NULL);
if (length)
goto out;
length = security_context_to_sid(buf, size, &sid, GFP_KERNEL);
if (length)
goto out;
length = security_sid_to_context(sid, &canon, &len);
if (length)
goto out;
length = -ERANGE;
if (len > SIMPLE_TRANSACTION_LIMIT) {
pr_err("SELinux: %s: context size (%u) exceeds "
"payload max\n", __func__, len);
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",
checkreqprot_get());
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 = avc_has_perm(current_sid(), SECINITSID_SECURITY,
SECCLASS_SECURITY, SECURITY__SETCHECKREQPROT,
NULL);
if (length)
return length;
if (count >= PAGE_SIZE)
return -ENOMEM;
/* No partial writes. */
if (*ppos != 0)
return -EINVAL;
page = memdup_user_nul(buf, count);
if (IS_ERR(page))
return PTR_ERR(page);
if (sscanf(page, "%u", &new_value) != 1) {
length = -EINVAL;
goto out;
}
length = count;
if (new_value) {
char comm[sizeof(current->comm)];
memcpy(comm, current->comm, sizeof(comm));
pr_err("SELinux: %s (%d) set checkreqprot to 1. This is no longer supported.\n",
comm, current->pid);
}
selinux_ima_measure_state();
out:
kfree(page);
return length;
}
static const struct file_operations sel_checkreqprot_ops = {
.read = sel_read_checkreqprot,
.write = sel_write_checkreqprot,
.llseek = generic_file_llseek,
};
static ssize_t sel_write_validatetrans(struct file *file,
const char __user *buf,
size_t count, loff_t *ppos)
{
char *oldcon = NULL, *newcon = NULL, *taskcon = NULL;
char *req = NULL;
u32 osid, nsid, tsid;
u16 tclass;
int rc;
rc = avc_has_perm(current_sid(), SECINITSID_SECURITY,
SECCLASS_SECURITY, SECURITY__VALIDATE_TRANS, NULL);
if (rc)
goto out;
rc = -ENOMEM;
if (count >= PAGE_SIZE)
goto out;
/* No partial writes. */
rc = -EINVAL;
if (*ppos != 0)
goto out;
req = memdup_user_nul(buf, count);
if (IS_ERR(req)) {
rc = PTR_ERR(req);
req = NULL;
goto out;
}
rc = -ENOMEM;
oldcon = kzalloc(count + 1, GFP_KERNEL);
if (!oldcon)
goto out;
newcon = kzalloc(count + 1, GFP_KERNEL);
if (!newcon)
goto out;
taskcon = kzalloc(count + 1, GFP_KERNEL);
if (!taskcon)
goto out;
rc = -EINVAL;
if (sscanf(req, "%s %s %hu %s", oldcon, newcon, &tclass, taskcon) != 4)
goto out;
rc = security_context_str_to_sid(oldcon, &osid, GFP_KERNEL);
if (rc)
goto out;
rc = security_context_str_to_sid(newcon, &nsid, GFP_KERNEL);
if (rc)
goto out;
rc = security_context_str_to_sid(taskcon, &tsid, GFP_KERNEL);
if (rc)
goto out;
rc = security_validate_transition_user(osid, nsid, tsid, tclass);
if (!rc)
rc = count;
out:
kfree(req);
kfree(oldcon);
kfree(newcon);
kfree(taskcon);
return rc;
}
static const struct file_operations sel_transition_ops = {
.write = sel_write_validatetrans,
.llseek = generic_file_llseek,
};
/*
* 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 (*const 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_inode(file)->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,
.llseek = generic_file_llseek,
};
/*
* 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 = NULL, *tcon = NULL;
u32 ssid, tsid;
u16 tclass;
struct av_decision avd;
ssize_t length;
length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
SECCLASS_SECURITY, SECURITY__COMPUTE_AV, NULL);
if (length)
goto out;
length = -ENOMEM;
scon = kzalloc(size + 1, GFP_KERNEL);
if (!scon)
goto out;
length = -ENOMEM;
tcon = kzalloc(size + 1, GFP_KERNEL);
if (!tcon)
goto out;
length = -EINVAL;
if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
goto out;
length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);
if (length)
goto out;
length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);
if (length)
goto out;
security_compute_av_user(ssid, tsid, tclass, &avd);
length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
"%x %x %x %x %u %x",
avd.allowed, 0xffffffff,
avd.auditallow, avd.auditdeny,
avd.seqno, avd.flags);
out:
kfree(tcon);
kfree(scon);
return length;
}
static ssize_t sel_write_create(struct file *file, char *buf, size_t size)
{
char *scon = NULL, *tcon = NULL;
char *namebuf = NULL, *objname = NULL;
u32 ssid, tsid, newsid;
u16 tclass;
ssize_t length;
char *newcon = NULL;
u32 len;
int nargs;
length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
SECCLASS_SECURITY, SECURITY__COMPUTE_CREATE,
NULL);
if (length)
goto out;
length = -ENOMEM;
scon = kzalloc(size + 1, GFP_KERNEL);
if (!scon)
goto out;
length = -ENOMEM;
tcon = kzalloc(size + 1, GFP_KERNEL);
if (!tcon)
goto out;
length = -ENOMEM;
namebuf = kzalloc(size + 1, GFP_KERNEL);
if (!namebuf)
goto out;
length = -EINVAL;
nargs = sscanf(buf, "%s %s %hu %s", scon, tcon, &tclass, namebuf);
if (nargs < 3 || nargs > 4)
goto out;
if (nargs == 4) {
/*
* If and when the name of new object to be queried contains
* either whitespace or multibyte characters, they shall be
* encoded based on the percentage-encoding rule.
* If not encoded, the sscanf logic picks up only left-half
* of the supplied name; split by a whitespace unexpectedly.
*/
char *r, *w;
int c1, c2;
r = w = namebuf;
do {
c1 = *r++;
if (c1 == '+')
c1 = ' ';
else if (c1 == '%') {
c1 = hex_to_bin(*r++);
if (c1 < 0)
goto out;
c2 = hex_to_bin(*r++);
if (c2 < 0)
goto out;
c1 = (c1 << 4) | c2;
}
*w++ = c1;
} while (c1 != '\0');
objname = namebuf;
}
length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);
if (length)
goto out;
length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);
if (length)
goto out;
length = security_transition_sid_user(ssid, tsid, tclass,
objname, &newsid);
if (length)
goto out;
length = security_sid_to_context(newsid, &newcon, &len);
if (length)
goto out;
length = -ERANGE;
if (len > SIMPLE_TRANSACTION_LIMIT) {
pr_err("SELinux: %s: context size (%u) exceeds "
"payload max\n", __func__, len);
goto out;
}
memcpy(buf, newcon, len);
length = len;
out:
kfree(newcon);
kfree(namebuf);
kfree(tcon);
kfree(scon);
return length;
}
static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size)
{
char *scon = NULL, *tcon = NULL;
u32 ssid, tsid, newsid;
u16 tclass;
ssize_t length;
char *newcon = NULL;
u32 len;
length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
SECCLASS_SECURITY, SECURITY__COMPUTE_RELABEL,
NULL);
if (length)
goto out;
length = -ENOMEM;
scon = kzalloc(size + 1, GFP_KERNEL);
if (!scon)
goto out;
length = -ENOMEM;
tcon = kzalloc(size + 1, GFP_KERNEL);
if (!tcon)
goto out;
length = -EINVAL;
if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
goto out;
length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);
if (length)
goto out;
length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);
if (length)
goto out;
length = security_change_sid(ssid, tsid, tclass, &newsid);
if (length)
goto out;
length = security_sid_to_context(newsid, &newcon, &len);
if (length)
goto out;
length = -ERANGE;
if (len > SIMPLE_TRANSACTION_LIMIT)
goto out;
memcpy(buf, newcon, len);
length = len;
out:
kfree(newcon);
kfree(tcon);
kfree(scon);
return length;
}
static ssize_t sel_write_user(struct file *file, char *buf, size_t size)
{
char *con = NULL, *user = NULL, *ptr;
u32 sid, *sids = NULL;
ssize_t length;
char *newcon;
int rc;
u32 i, len, nsids;
length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
SECCLASS_SECURITY, SECURITY__COMPUTE_USER,
NULL);
if (length)
goto out;
length = -ENOMEM;
con = kzalloc(size + 1, GFP_KERNEL);
if (!con)
goto out;
length = -ENOMEM;
user = kzalloc(size + 1, GFP_KERNEL);
if (!user)
goto out;
length = -EINVAL;
if (sscanf(buf, "%s %s", con, user) != 2)
goto out;
length = security_context_str_to_sid(con, &sid, GFP_KERNEL);
if (length)
goto out;
length = security_get_user_sids(sid, user, &sids, &nsids);
if (length)
goto out;
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 out;
}
if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
kfree(newcon);
length = -ERANGE;
goto out;
}
memcpy(ptr, newcon, len);
kfree(newcon);
ptr += len;
length += len;
}
out:
kfree(sids);
kfree(user);
kfree(con);
return length;
}
static ssize_t sel_write_member(struct file *file, char *buf, size_t size)
{
char *scon = NULL, *tcon = NULL;
u32 ssid, tsid, newsid;
u16 tclass;
ssize_t length;
char *newcon = NULL;
u32 len;
length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
SECCLASS_SECURITY, SECURITY__COMPUTE_MEMBER,
NULL);
if (length)
goto out;
length = -ENOMEM;
scon = kzalloc(size + 1, GFP_KERNEL);
if (!scon)
goto out;
length = -ENOMEM;
tcon = kzalloc(size + 1, GFP_KERNEL);
if (!tcon)
goto out;
length = -EINVAL;
if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
goto out;
length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);
if (length)
goto out;
length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);
if (length)
goto out;
length = security_member_sid(ssid, tsid, tclass, &newsid);
if (length)
goto out;
length = security_sid_to_context(newsid, &newcon, &len);
if (length)
goto out;
length = -ERANGE;
if (len > SIMPLE_TRANSACTION_LIMIT) {
pr_err("SELinux: %s: context size (%u) exceeds "
"payload max\n", __func__, len);
goto out;
}
memcpy(buf, newcon, len);
length = len;
out:
kfree(newcon);
kfree(tcon);
kfree(scon);
return length;
}
static struct inode *sel_make_inode(struct super_block *sb, umode_t mode)
{
struct inode *ret = new_inode(sb);
if (ret) {
ret->i_mode = mode;
simple_inode_init_ts(ret);
}
return ret;
}
static ssize_t sel_read_bool(struct file *filep, char __user *buf,
size_t count, loff_t *ppos)
{
struct selinux_fs_info *fsi = file_inode(filep)->i_sb->s_fs_info;
char *page = NULL;
ssize_t length;
ssize_t ret;
int cur_enforcing;
unsigned index = file_inode(filep)->i_ino & SEL_INO_MASK;
const char *name = filep->f_path.dentry->d_name.name;
mutex_lock(&selinux_state.policy_mutex);
ret = -EINVAL;
if (index >= fsi->bool_num || strcmp(name,
fsi->bool_pending_names[index]))
goto out_unlock;
ret = -ENOMEM;
page = (char *)get_zeroed_page(GFP_KERNEL);
if (!page)
goto out_unlock;
cur_enforcing = security_get_bool_value(index);
if (cur_enforcing < 0) {
ret = cur_enforcing;
goto out_unlock;
}
length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
fsi->bool_pending_values[index]);
mutex_unlock(&selinux_state.policy_mutex);
ret = simple_read_from_buffer(buf, count, ppos, page, length);
out_free:
free_page((unsigned long)page);
return ret;
out_unlock:
mutex_unlock(&selinux_state.policy_mutex);
goto out_free;
}
static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
size_t count, loff_t *ppos)
{
struct selinux_fs_info *fsi = file_inode(filep)->i_sb->s_fs_info;
char *page = NULL;
ssize_t length;
int new_value;
unsigned index = file_inode(filep)->i_ino & SEL_INO_MASK;
const char *name = filep->f_path.dentry->d_name.name;
if (count >= PAGE_SIZE)
return -ENOMEM;
/* No partial writes. */
if (*ppos != 0)
return -EINVAL;
page = memdup_user_nul(buf, count);
if (IS_ERR(page))
return PTR_ERR(page);
mutex_lock(&selinux_state.policy_mutex);
length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
SECCLASS_SECURITY, SECURITY__SETBOOL,
NULL);
if (length)
goto out;
length = -EINVAL;
if (index >= fsi->bool_num || strcmp(name,
fsi->bool_pending_names[index]))
goto out;
length = -EINVAL;
if (sscanf(page, "%d", &new_value) != 1)
goto out;
if (new_value)
new_value = 1;
fsi->bool_pending_values[index] = new_value;
length = count;
out:
mutex_unlock(&selinux_state.policy_mutex);
kfree(page);
return length;
}
static const struct file_operations sel_bool_ops = {
.read = sel_read_bool,
.write = sel_write_bool,
.llseek = generic_file_llseek,
};
static ssize_t sel_commit_bools_write(struct file *filep,
const char __user *buf,
size_t count, loff_t *ppos)
{
struct selinux_fs_info *fsi = file_inode(filep)->i_sb->s_fs_info;
char *page = NULL;
ssize_t length;
int new_value;
if (count >= PAGE_SIZE)
return -ENOMEM;
/* No partial writes. */
if (*ppos != 0)
return -EINVAL;
page = memdup_user_nul(buf, count);
if (IS_ERR(page))
return PTR_ERR(page);
mutex_lock(&selinux_state.policy_mutex);
length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
SECCLASS_SECURITY, SECURITY__SETBOOL,
NULL);
if (length)
goto out;
length = -EINVAL;
if (sscanf(page, "%d", &new_value) != 1)
goto out;
length = 0;
if (new_value && fsi->bool_pending_values)
length = security_set_bools(fsi->bool_num,
fsi->bool_pending_values);
if (!length)
length = count;
out:
mutex_unlock(&selinux_state.policy_mutex);
kfree(page);
return length;
}
static const struct file_operations sel_commit_bools_ops = {
.write = sel_commit_bools_write,
.llseek = generic_file_llseek,
};
static int sel_make_bools(struct selinux_policy *newpolicy, struct dentry *bool_dir,
unsigned int *bool_num, char ***bool_pending_names,
int **bool_pending_values)
{
int ret;
char **names, *page;
u32 i, num;
page = (char *)get_zeroed_page(GFP_KERNEL);
if (!page)
return -ENOMEM;
ret = security_get_bools(newpolicy, &num, &names, bool_pending_values);
if (ret)
goto out;
*bool_num = num;
*bool_pending_names = names;
for (i = 0; i < num; i++) {
struct dentry *dentry;
struct inode *inode;
struct inode_security_struct *isec;
ssize_t len;
u32 sid;
len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
if (len >= PAGE_SIZE) {
ret = -ENAMETOOLONG;
break;
}
dentry = d_alloc_name(bool_dir, names[i]);
if (!dentry) {
ret = -ENOMEM;
break;
}
inode = sel_make_inode(bool_dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
if (!inode) {
dput(dentry);
ret = -ENOMEM;
break;
}
isec = selinux_inode(inode);
ret = selinux_policy_genfs_sid(newpolicy, "selinuxfs", page,
SECCLASS_FILE, &sid);
if (ret) {
pr_warn_ratelimited("SELinux: no sid found, defaulting to security isid for %s\n",
page);
sid = SECINITSID_SECURITY;
}
isec->sid = sid;
isec->initialized = LABEL_INITIALIZED;
inode->i_fop = &sel_bool_ops;
inode->i_ino = i|SEL_BOOL_INO_OFFSET;
d_add(dentry, inode);
}
out:
free_page((unsigned long)page);
return ret;
}
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_get_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;
unsigned int new_value;
ret = avc_has_perm(current_sid(), SECINITSID_SECURITY,
SECCLASS_SECURITY, SECURITY__SETSECPARAM,
NULL);
if (ret)
return ret;
if (count >= PAGE_SIZE)
return -ENOMEM;
/* No partial writes. */
if (*ppos != 0)
return -EINVAL;
page = memdup_user_nul(buf, count);
if (IS_ERR(page))
return PTR_ERR(page);
ret = -EINVAL;
if (sscanf(page, "%u", &new_value) != 1)
goto out;
avc_set_cache_threshold(new_value);
ret = count;
out:
kfree(page);
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 length;
page = (char *)__get_free_page(GFP_KERNEL);
if (!page)
return -ENOMEM;
length = avc_get_hash_stats(page);
if (length >= 0)
length = simple_read_from_buffer(buf, count, ppos, page, length);
free_page((unsigned long)page);
return length;
}
static ssize_t sel_read_sidtab_hash_stats(struct file *filp, char __user *buf,
size_t count, loff_t *ppos)
{
char *page;
ssize_t length;
page = (char *)__get_free_page(GFP_KERNEL);
if (!page)
return -ENOMEM;
length = security_sidtab_hash_stats(page);
if (length >= 0)
length = simple_read_from_buffer(buf, count, ppos, page,
length);
free_page((unsigned long)page);
return length;
}
static const struct file_operations sel_sidtab_hash_stats_ops = {
.read = sel_read_sidtab_hash_stats,
.llseek = generic_file_llseek,
};
static const struct file_operations sel_avc_cache_threshold_ops = {
.read = sel_read_avc_cache_threshold,
.write = sel_write_avc_cache_threshold,
.llseek = generic_file_llseek,
};
static const struct file_operations sel_avc_hash_stats_ops = {
.read = sel_read_avc_hash_stats,
.llseek = generic_file_llseek,
};
#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);
}
(*idx)++;
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_puts(seq,
"lookups hits misses allocations reclaims frees\n");
} else {
unsigned int lookups = st->lookups;
unsigned int misses = st->misses;
unsigned int hits = lookups - misses;
seq_printf(seq, "%u %u %u %u %u %u\n", lookups,
hits, 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)
{
struct super_block *sb = dir->d_sb;
struct selinux_fs_info *fsi = sb->s_fs_info;
unsigned int i;
static const 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)
return -ENOMEM;
inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
if (!inode) {
dput(dentry);
return -ENOMEM;
}
inode->i_fop = files[i].ops;
inode->i_ino = ++fsi->last_ino;
d_add(dentry, inode);
}
return 0;
}
static int sel_make_ss_files(struct dentry *dir)
{
struct super_block *sb = dir->d_sb;
struct selinux_fs_info *fsi = sb->s_fs_info;
unsigned int i;
static const struct tree_descr files[] = {
{ "sidtab_hash_stats", &sel_sidtab_hash_stats_ops, S_IRUGO },
};
for (i = 0; i < ARRAY_SIZE(files); i++) {
struct inode *inode;
struct dentry *dentry;
dentry = d_alloc_name(dir, files[i].name);
if (!dentry)
return -ENOMEM;
inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
if (!inode) {
dput(dentry);
return -ENOMEM;
}
inode->i_fop = files[i].ops;
inode->i_ino = ++fsi->last_ino;
d_add(dentry, inode);
}
return 0;
}
static ssize_t sel_read_initcon(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
char *con;
u32 sid, len;
ssize_t ret;
sid = file_inode(file)->i_ino&SEL_INO_MASK;
ret = security_sid_to_context(sid, &con, &len);
if (ret)
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,
.llseek = generic_file_llseek,
};
static int sel_make_initcon_files(struct dentry *dir)
{
unsigned int i;
for (i = 1; i <= SECINITSID_NUM; i++) {
struct inode *inode;
struct dentry *dentry;
const char *s = security_get_initial_sid_context(i);
if (!s)
continue;
dentry = d_alloc_name(dir, s);
if (!dentry)
return -ENOMEM;
inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
if (!inode) {
dput(dentry);
return -ENOMEM;
}
inode->i_fop = &sel_initcon_ops;
inode->i_ino = i|SEL_INITCON_INO_OFFSET;
d_add(dentry, inode);
}
return 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 (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)
{
unsigned long ino = file_inode(file)->i_ino;
char res[TMPBUFLEN];
ssize_t len = scnprintf(res, sizeof(res), "%d", sel_ino_to_class(ino));
return simple_read_from_buffer(buf, count, ppos, res, len);
}
static const struct file_operations sel_class_ops = {
.read = sel_read_class,
.llseek = generic_file_llseek,
};
static ssize_t sel_read_perm(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
unsigned long ino = file_inode(file)->i_ino;
char res[TMPBUFLEN];
ssize_t len = scnprintf(res, sizeof(res), "%d", sel_ino_to_perm(ino));
return simple_read_from_buffer(buf, count, ppos, res, len);
}
static const struct file_operations sel_perm_ops = {
.read = sel_read_perm,
.llseek = generic_file_llseek,
};
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_inode(file)->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,
.llseek = generic_file_llseek,
};
static int sel_make_perm_files(struct selinux_policy *newpolicy,
char *objclass, int classvalue,
struct dentry *dir)
{
u32 i, nperms;
int rc;
char **perms;
rc = security_get_permissions(newpolicy, objclass, &perms, &nperms);
if (rc)
return rc;
for (i = 0; i < nperms; i++) {
struct inode *inode;
struct dentry *dentry;
rc = -ENOMEM;
dentry = d_alloc_name(dir, perms[i]);
if (!dentry)
goto out;
rc = -ENOMEM;
inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
if (!inode) {
dput(dentry);
goto out;
}
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);
}
rc = 0;
out:
for (i = 0; i < nperms; i++)
kfree(perms[i]);
kfree(perms);
return rc;
}
static int sel_make_class_dir_entries(struct selinux_policy *newpolicy,
char *classname, int index,
struct dentry *dir)
{
struct super_block *sb = dir->d_sb;
struct selinux_fs_info *fsi = sb->s_fs_info;
struct dentry *dentry = NULL;
struct inode *inode = NULL;
dentry = d_alloc_name(dir, "index");
if (!dentry)
return -ENOMEM;
inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
if (!inode) {
dput(dentry);
return -ENOMEM;
}
inode->i_fop = &sel_class_ops;
inode->i_ino = sel_class_to_ino(index);
d_add(dentry, inode);
dentry = sel_make_dir(dir, "perms", &fsi->last_class_ino);
if (IS_ERR(dentry))
return PTR_ERR(dentry);
return sel_make_perm_files(newpolicy, classname, index, dentry);
}
static int sel_make_classes(struct selinux_policy *newpolicy,
struct dentry *class_dir,
unsigned long *last_class_ino)
{
u32 i, nclasses;
int rc;
char **classes;
rc = security_get_classes(newpolicy, &classes, &nclasses);
if (rc)
return rc;
/* +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 = sel_make_dir(class_dir, classes[i],
last_class_ino);
if (IS_ERR(class_name_dir)) {
rc = PTR_ERR(class_name_dir);
goto out;
}
/* i+1 since class values are 1-indexed */
rc = sel_make_class_dir_entries(newpolicy, classes[i], i + 1,
class_name_dir);
if (rc)
goto out;
}
rc = 0;
out:
for (i = 0; i < nclasses; i++)
kfree(classes[i]);
kfree(classes);
return rc;
}
static int sel_make_policycap(struct selinux_fs_info *fsi)
{
unsigned int iter;
struct dentry *dentry = NULL;
struct inode *inode = NULL;
for (iter = 0; iter <= POLICYDB_CAP_MAX; iter++) {
if (iter < ARRAY_SIZE(selinux_policycap_names))
dentry = d_alloc_name(fsi->policycap_dir,
selinux_policycap_names[iter]);
else
dentry = d_alloc_name(fsi->policycap_dir, "unknown");
if (dentry == NULL)
return -ENOMEM;
inode = sel_make_inode(fsi->sb, S_IFREG | 0444);
if (inode == NULL) {
dput(dentry);
return -ENOMEM;
}
inode->i_fop = &sel_policycap_ops;
inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET;
d_add(dentry, inode);
}
return 0;
}
static struct dentry *sel_make_dir(struct dentry *dir, const char *name,
unsigned long *ino)
{
struct dentry *dentry = d_alloc_name(dir, name);
struct inode *inode;
if (!dentry)
return ERR_PTR(-ENOMEM);
inode = sel_make_inode(dir->d_sb, S_IFDIR | S_IRUGO | S_IXUGO);
if (!inode) {
dput(dentry);
return ERR_PTR(-ENOMEM);
}
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(d_inode(dir));
return dentry;
}
static int reject_all(struct mnt_idmap *idmap, struct inode *inode, int mask)
{
return -EPERM; // no access for anyone, root or no root.
}
static const struct inode_operations swapover_dir_inode_operations = {
.lookup = simple_lookup,
.permission = reject_all,
};
static struct dentry *sel_make_swapover_dir(struct super_block *sb,
unsigned long *ino)
{
struct dentry *dentry = d_alloc_name(sb->s_root, ".swapover");
struct inode *inode;
if (!dentry)
return ERR_PTR(-ENOMEM);
inode = sel_make_inode(sb, S_IFDIR);
if (!inode) {
dput(dentry);
return ERR_PTR(-ENOMEM);
}
inode->i_op = &swapover_dir_inode_operations;
inode->i_ino = ++(*ino);
/* directory inodes start off with i_nlink == 2 (for "." entry) */
inc_nlink(inode);
inode_lock(sb->s_root->d_inode);
d_add(dentry, inode);
inc_nlink(sb->s_root->d_inode);
inode_unlock(sb->s_root->d_inode);
return dentry;
}
#define NULL_FILE_NAME "null"
static int sel_fill_super(struct super_block *sb, struct fs_context *fc)
{
struct selinux_fs_info *fsi;
int ret;
struct dentry *dentry;
struct inode *inode;
struct inode_security_struct *isec;
static const 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},
[SEL_STATUS] = {"status", &sel_handle_status_ops, S_IRUGO},
[SEL_POLICY] = {"policy", &sel_policy_ops, S_IRUGO},
[SEL_VALIDATE_TRANS] = {"validatetrans", &sel_transition_ops,
S_IWUGO},
/* last one */ {""}
};
ret = selinux_fs_info_create(sb);
if (ret)
goto err;
ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
if (ret)
goto err;
fsi = sb->s_fs_info;
fsi->bool_dir = sel_make_dir(sb->s_root, BOOL_DIR_NAME, &fsi->last_ino);
if (IS_ERR(fsi->bool_dir)) {
ret = PTR_ERR(fsi->bool_dir);
fsi->bool_dir = NULL;
goto err;
}
ret = -ENOMEM;
dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
if (!dentry)
goto err;
ret = -ENOMEM;
inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
if (!inode) {
dput(dentry);
goto err;
}
inode->i_ino = ++fsi->last_ino;
isec = selinux_inode(inode);
isec->sid = SECINITSID_DEVNULL;
isec->sclass = SECCLASS_CHR_FILE;
isec->initialized = LABEL_INITIALIZED;
init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
d_add(dentry, inode);
dentry = sel_make_dir(sb->s_root, "avc", &fsi->last_ino);
if (IS_ERR(dentry)) {
ret = PTR_ERR(dentry);
goto err;
}
ret = sel_make_avc_files(dentry);
if (ret)
goto err;
dentry = sel_make_dir(sb->s_root, "ss", &fsi->last_ino);
if (IS_ERR(dentry)) {
ret = PTR_ERR(dentry);
goto err;
}
ret = sel_make_ss_files(dentry);
if (ret)
goto err;
dentry = sel_make_dir(sb->s_root, "initial_contexts", &fsi->last_ino);
if (IS_ERR(dentry)) {
ret = PTR_ERR(dentry);
goto err;
}
ret = sel_make_initcon_files(dentry);
if (ret)
goto err;
fsi->class_dir = sel_make_dir(sb->s_root, CLASS_DIR_NAME, &fsi->last_ino);
if (IS_ERR(fsi->class_dir)) {
ret = PTR_ERR(fsi->class_dir);
fsi->class_dir = NULL;
goto err;
}
fsi->policycap_dir = sel_make_dir(sb->s_root, POLICYCAP_DIR_NAME,
&fsi->last_ino);
if (IS_ERR(fsi->policycap_dir)) {
ret = PTR_ERR(fsi->policycap_dir);
fsi->policycap_dir = NULL;
goto err;
}
ret = sel_make_policycap(fsi);
if (ret) {
pr_err("SELinux: failed to load policy capabilities\n");
goto err;
}
return 0;
err:
pr_err("SELinux: %s: failed while creating inodes\n",
__func__);
selinux_fs_info_free(sb);
return ret;
}
static int sel_get_tree(struct fs_context *fc)
{
return get_tree_single(fc, sel_fill_super);
}
static const struct fs_context_operations sel_context_ops = {
.get_tree = sel_get_tree,
};
static int sel_init_fs_context(struct fs_context *fc)
{
fc->ops = &sel_context_ops;
return 0;
}
static void sel_kill_sb(struct super_block *sb)
{
selinux_fs_info_free(sb);
kill_litter_super(sb);
}
static struct file_system_type sel_fs_type = {
.name = "selinuxfs",
.init_fs_context = sel_init_fs_context,
.kill_sb = sel_kill_sb,
};
struct path selinux_null __ro_after_init;
static int __init init_sel_fs(void)
{
struct qstr null_name = QSTR_INIT(NULL_FILE_NAME,
sizeof(NULL_FILE_NAME)-1);
int err;
if (!selinux_enabled_boot)
return 0;
err = sysfs_create_mount_point(fs_kobj, "selinux");
if (err)
return err;
err = register_filesystem(&sel_fs_type);
if (err) {
sysfs_remove_mount_point(fs_kobj, "selinux");
return err;
}
selinux_null.mnt = kern_mount(&sel_fs_type);
if (IS_ERR(selinux_null.mnt)) {
pr_err("selinuxfs: could not mount!\n");
err = PTR_ERR(selinux_null.mnt);
selinux_null.mnt = NULL;
return err;
}
selinux_null.dentry = d_hash_and_lookup(selinux_null.mnt->mnt_root,
&null_name);
if (IS_ERR(selinux_null.dentry)) {
pr_err("selinuxfs: could not lookup null!\n");
err = PTR_ERR(selinux_null.dentry);
selinux_null.dentry = NULL;
return err;
}
/*
* Try to pre-allocate the status page, so the sequence number of the
* initial policy load can be stored.
*/
(void) selinux_kernel_status_page();
return err;
}
__initcall(init_sel_fs);
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