--- /dev/null
+What: security/evm
+Date: March 2011
+Contact: Mimi Zohar <zohar@us.ibm.com>
+Description:
+ EVM protects a file's security extended attributes(xattrs)
+ against integrity attacks. The initial method maintains an
+ HMAC-sha1 value across the extended attributes, storing the
+ value as the extended attribute 'security.evm'.
+
+ EVM depends on the Kernel Key Retention System to provide it
+ with a trusted/encrypted key for the HMAC-sha1 operation.
+ The key is loaded onto the root's keyring using keyctl. Until
+ EVM receives notification that the key has been successfully
+ loaded onto the keyring (echo 1 > <securityfs>/evm), EVM
+ can not create or validate the 'security.evm' xattr, but
+ returns INTEGRITY_UNKNOWN. Loading the key and signaling EVM
+ should be done as early as possible. Normally this is done
+ in the initramfs, which has already been measured as part
+ of the trusted boot. For more information on creating and
+ loading existing trusted/encrypted keys, refer to:
+ Documentation/keys-trusted-encrypted.txt. (A sample dracut
+ patch, which loads the trusted/encrypted key and enables
+ EVM, is available from http://linux-ima.sourceforge.net/#EVM.)
EDD BIOS Enhanced Disk Drive Services (EDD) is enabled
EFI EFI Partitioning (GPT) is enabled
EIDE EIDE/ATAPI support is enabled.
+ EVM Extended Verification Module
FB The frame buffer device is enabled.
GCOV GCOV profiling is enabled.
HW Appropriate hardware is enabled.
This option is obsoleted by the "netdev=" option, which
has equivalent usage. See its documentation for details.
+ evm= [EVM]
+ Format: { "fix" }
+ Permit 'security.evm' to be updated regardless of
+ current integrity status.
+
failslab=
fail_page_alloc=
fail_make_request=[KNL]
#include <linux/fsnotify.h>
#include <linux/fcntl.h>
#include <linux/security.h>
+#include <linux/evm.h>
/**
* inode_change_ok - check if attribute changes to an inode are allowed
else
error = simple_setattr(dentry, attr);
- if (!error)
+ if (!error) {
fsnotify_change(dentry, ia_valid);
+ evm_inode_post_setattr(dentry, ia_valid);
+ }
return error;
}
XATTR_REPLACE);
}
-int btrfs_xattr_security_init(struct btrfs_trans_handle *trans,
- struct inode *inode, struct inode *dir,
- const struct qstr *qstr)
+int btrfs_initxattrs(struct inode *inode, const struct xattr *xattr_array,
+ void *fs_info)
{
- int err;
- size_t len;
- void *value;
- char *suffix;
+ const struct xattr *xattr;
+ struct btrfs_trans_handle *trans = fs_info;
char *name;
+ int err = 0;
- err = security_inode_init_security(inode, dir, qstr, &suffix, &value,
- &len);
- if (err) {
- if (err == -EOPNOTSUPP)
- return 0;
- return err;
- }
-
- name = kmalloc(XATTR_SECURITY_PREFIX_LEN + strlen(suffix) + 1,
- GFP_NOFS);
- if (!name) {
- err = -ENOMEM;
- } else {
+ for (xattr = xattr_array; xattr->name != NULL; xattr++) {
+ name = kmalloc(XATTR_SECURITY_PREFIX_LEN +
+ strlen(xattr->name) + 1, GFP_NOFS);
+ if (!name) {
+ err = -ENOMEM;
+ break;
+ }
strcpy(name, XATTR_SECURITY_PREFIX);
- strcpy(name + XATTR_SECURITY_PREFIX_LEN, suffix);
- err = __btrfs_setxattr(trans, inode, name, value, len, 0);
+ strcpy(name + XATTR_SECURITY_PREFIX_LEN, xattr->name);
+ err = __btrfs_setxattr(trans, inode, name,
+ xattr->value, xattr->value_len, 0);
kfree(name);
+ if (err < 0)
+ break;
}
-
- kfree(suffix);
- kfree(value);
return err;
}
+
+int btrfs_xattr_security_init(struct btrfs_trans_handle *trans,
+ struct inode *inode, struct inode *dir,
+ const struct qstr *qstr)
+{
+ return security_inode_init_security(inode, dir, qstr,
+ &btrfs_initxattrs, trans);
+}
value, size, flags);
}
-int
-ext2_init_security(struct inode *inode, struct inode *dir,
- const struct qstr *qstr)
+int ext2_initxattrs(struct inode *inode, const struct xattr *xattr_array,
+ void *fs_info)
{
- int err;
- size_t len;
- void *value;
- char *name;
+ const struct xattr *xattr;
+ int err = 0;
- err = security_inode_init_security(inode, dir, qstr, &name, &value, &len);
- if (err) {
- if (err == -EOPNOTSUPP)
- return 0;
- return err;
+ for (xattr = xattr_array; xattr->name != NULL; xattr++) {
+ err = ext2_xattr_set(inode, EXT2_XATTR_INDEX_SECURITY,
+ xattr->name, xattr->value,
+ xattr->value_len, 0);
+ if (err < 0)
+ break;
}
- err = ext2_xattr_set(inode, EXT2_XATTR_INDEX_SECURITY,
- name, value, len, 0);
- kfree(name);
- kfree(value);
return err;
}
+int
+ext2_init_security(struct inode *inode, struct inode *dir,
+ const struct qstr *qstr)
+{
+ return security_inode_init_security(inode, dir, qstr,
+ &ext2_initxattrs, NULL);
+}
+
const struct xattr_handler ext2_xattr_security_handler = {
.prefix = XATTR_SECURITY_PREFIX,
.list = ext2_xattr_security_list,
name, value, size, flags);
}
-int
-ext3_init_security(handle_t *handle, struct inode *inode, struct inode *dir,
- const struct qstr *qstr)
+int ext3_initxattrs(struct inode *inode, const struct xattr *xattr_array,
+ void *fs_info)
{
- int err;
- size_t len;
- void *value;
- char *name;
+ const struct xattr *xattr;
+ handle_t *handle = fs_info;
+ int err = 0;
- err = security_inode_init_security(inode, dir, qstr, &name, &value, &len);
- if (err) {
- if (err == -EOPNOTSUPP)
- return 0;
- return err;
+ for (xattr = xattr_array; xattr->name != NULL; xattr++) {
+ err = ext3_xattr_set_handle(handle, inode,
+ EXT3_XATTR_INDEX_SECURITY,
+ xattr->name, xattr->value,
+ xattr->value_len, 0);
+ if (err < 0)
+ break;
}
- err = ext3_xattr_set_handle(handle, inode, EXT3_XATTR_INDEX_SECURITY,
- name, value, len, 0);
- kfree(name);
- kfree(value);
return err;
}
+int
+ext3_init_security(handle_t *handle, struct inode *inode, struct inode *dir,
+ const struct qstr *qstr)
+{
+ return security_inode_init_security(inode, dir, qstr,
+ &ext3_initxattrs, handle);
+}
+
const struct xattr_handler ext3_xattr_security_handler = {
.prefix = XATTR_SECURITY_PREFIX,
.list = ext3_xattr_security_list,
name, value, size, flags);
}
-int
-ext4_init_security(handle_t *handle, struct inode *inode, struct inode *dir,
- const struct qstr *qstr)
+int ext4_initxattrs(struct inode *inode, const struct xattr *xattr_array,
+ void *fs_info)
{
- int err;
- size_t len;
- void *value;
- char *name;
+ const struct xattr *xattr;
+ handle_t *handle = fs_info;
+ int err = 0;
- err = security_inode_init_security(inode, dir, qstr, &name, &value, &len);
- if (err) {
- if (err == -EOPNOTSUPP)
- return 0;
- return err;
+ for (xattr = xattr_array; xattr->name != NULL; xattr++) {
+ err = ext4_xattr_set_handle(handle, inode,
+ EXT4_XATTR_INDEX_SECURITY,
+ xattr->name, xattr->value,
+ xattr->value_len, 0);
+ if (err < 0)
+ break;
}
- err = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_SECURITY,
- name, value, len, 0);
- kfree(name);
- kfree(value);
return err;
}
+int
+ext4_init_security(handle_t *handle, struct inode *inode, struct inode *dir,
+ const struct qstr *qstr)
+{
+ return security_inode_init_security(inode, dir, qstr,
+ &ext4_initxattrs, handle);
+}
+
const struct xattr_handler ext4_xattr_security_handler = {
.prefix = XATTR_SECURITY_PREFIX,
.list = ext4_xattr_security_list,
return error;
}
-static int gfs2_security_init(struct gfs2_inode *dip, struct gfs2_inode *ip,
- const struct qstr *qstr)
+int gfs2_initxattrs(struct inode *inode, const struct xattr *xattr_array,
+ void *fs_info)
{
- int err;
- size_t len;
- void *value;
- char *name;
-
- err = security_inode_init_security(&ip->i_inode, &dip->i_inode, qstr,
- &name, &value, &len);
-
- if (err) {
- if (err == -EOPNOTSUPP)
- return 0;
- return err;
+ const struct xattr *xattr;
+ int err = 0;
+
+ for (xattr = xattr_array; xattr->name != NULL; xattr++) {
+ err = __gfs2_xattr_set(inode, xattr->name, xattr->value,
+ xattr->value_len, 0,
+ GFS2_EATYPE_SECURITY);
+ if (err < 0)
+ break;
}
-
- err = __gfs2_xattr_set(&ip->i_inode, name, value, len, 0,
- GFS2_EATYPE_SECURITY);
- kfree(value);
- kfree(name);
-
return err;
}
+static int gfs2_security_init(struct gfs2_inode *dip, struct gfs2_inode *ip,
+ const struct qstr *qstr)
+{
+ return security_inode_init_security(&ip->i_inode, &dip->i_inode, qstr,
+ &gfs2_initxattrs, NULL);
+}
+
/**
* gfs2_create_inode - Create a new inode
* @dir: The parent directory
#include <linux/security.h>
#include "nodelist.h"
-/* ---- Initial Security Label Attachment -------------- */
-int jffs2_init_security(struct inode *inode, struct inode *dir,
- const struct qstr *qstr)
+/* ---- Initial Security Label(s) Attachment callback --- */
+int jffs2_initxattrs(struct inode *inode, const struct xattr *xattr_array,
+ void *fs_info)
{
- int rc;
- size_t len;
- void *value;
- char *name;
+ const struct xattr *xattr;
+ int err = 0;
- rc = security_inode_init_security(inode, dir, qstr, &name, &value, &len);
- if (rc) {
- if (rc == -EOPNOTSUPP)
- return 0;
- return rc;
+ for (xattr = xattr_array; xattr->name != NULL; xattr++) {
+ err = do_jffs2_setxattr(inode, JFFS2_XPREFIX_SECURITY,
+ xattr->name, xattr->value,
+ xattr->value_len, 0);
+ if (err < 0)
+ break;
}
- rc = do_jffs2_setxattr(inode, JFFS2_XPREFIX_SECURITY, name, value, len, 0);
+ return err;
+}
- kfree(name);
- kfree(value);
- return rc;
+/* ---- Initial Security Label(s) Attachment ----------- */
+int jffs2_init_security(struct inode *inode, struct inode *dir,
+ const struct qstr *qstr)
+{
+ return security_inode_init_security(inode, dir, qstr,
+ &jffs2_initxattrs, NULL);
}
/* ---- XATTR Handler for "security.*" ----------------- */
}
#ifdef CONFIG_JFS_SECURITY
-int jfs_init_security(tid_t tid, struct inode *inode, struct inode *dir,
- const struct qstr *qstr)
+int jfs_initxattrs(struct inode *inode, const struct xattr *xattr_array,
+ void *fs_info)
{
- int rc;
- size_t len;
- void *value;
- char *suffix;
+ const struct xattr *xattr;
+ tid_t *tid = fs_info;
char *name;
-
- rc = security_inode_init_security(inode, dir, qstr, &suffix, &value,
- &len);
- if (rc) {
- if (rc == -EOPNOTSUPP)
- return 0;
- return rc;
- }
- name = kmalloc(XATTR_SECURITY_PREFIX_LEN + 1 + strlen(suffix),
- GFP_NOFS);
- if (!name) {
- rc = -ENOMEM;
- goto kmalloc_failed;
+ int err = 0;
+
+ for (xattr = xattr_array; xattr->name != NULL; xattr++) {
+ name = kmalloc(XATTR_SECURITY_PREFIX_LEN +
+ strlen(xattr->name) + 1, GFP_NOFS);
+ if (!name) {
+ err = -ENOMEM;
+ break;
+ }
+ strcpy(name, XATTR_SECURITY_PREFIX);
+ strcpy(name + XATTR_SECURITY_PREFIX_LEN, xattr->name);
+
+ err = __jfs_setxattr(*tid, inode, name,
+ xattr->value, xattr->value_len, 0);
+ kfree(name);
+ if (err < 0)
+ break;
}
- strcpy(name, XATTR_SECURITY_PREFIX);
- strcpy(name + XATTR_SECURITY_PREFIX_LEN, suffix);
-
- rc = __jfs_setxattr(tid, inode, name, value, len, 0);
-
- kfree(name);
-kmalloc_failed:
- kfree(suffix);
- kfree(value);
+ return err;
+}
- return rc;
+int jfs_init_security(tid_t tid, struct inode *inode, struct inode *dir,
+ const struct qstr *qstr)
+{
+ return security_inode_init_security(inode, dir, qstr,
+ &jfs_initxattrs, &tid);
}
#endif
{
int ret = 0;
struct buffer_head *dir_bh = NULL;
- struct ocfs2_security_xattr_info si = {
- .enable = 1,
- };
- ret = ocfs2_init_security_get(inode, dir, qstr, &si);
+ ret = ocfs2_init_security_get(inode, dir, qstr, NULL);
if (!ret) {
- ret = ocfs2_xattr_set(inode, OCFS2_XATTR_INDEX_SECURITY,
- si.name, si.value, si.value_len,
- XATTR_CREATE);
- if (ret) {
- mlog_errno(ret);
- goto leave;
- }
- } else if (ret != -EOPNOTSUPP) {
mlog_errno(ret);
goto leave;
}
name, value, size, flags);
}
+int ocfs2_initxattrs(struct inode *inode, const struct xattr *xattr_array,
+ void *fs_info)
+{
+ const struct xattr *xattr;
+ int err = 0;
+
+ for (xattr = xattr_array; xattr->name != NULL; xattr++) {
+ err = ocfs2_xattr_set(inode, OCFS2_XATTR_INDEX_SECURITY,
+ xattr->name, xattr->value,
+ xattr->value_len, XATTR_CREATE);
+ if (err)
+ break;
+ }
+ return err;
+}
+
int ocfs2_init_security_get(struct inode *inode,
struct inode *dir,
const struct qstr *qstr,
/* check whether ocfs2 support feature xattr */
if (!ocfs2_supports_xattr(OCFS2_SB(dir->i_sb)))
return -EOPNOTSUPP;
- return security_inode_init_security(inode, dir, qstr, &si->name,
- &si->value, &si->value_len);
+ if (si)
+ return security_old_inode_init_security(inode, dir, qstr,
+ &si->name, &si->value,
+ &si->value_len);
+
+ return security_inode_init_security(inode, dir, qstr,
+ &ocfs2_initxattrs, NULL);
}
int ocfs2_init_security_set(handle_t *handle,
if (IS_PRIVATE(dir))
return 0;
- error = security_inode_init_security(inode, dir, qstr, &sec->name,
- &sec->value, &sec->length);
+ error = security_old_inode_init_security(inode, dir, qstr, &sec->name,
+ &sec->value, &sec->length);
if (error) {
if (error == -EOPNOTSUPP)
error = 0;
#include <linux/mount.h>
#include <linux/namei.h>
#include <linux/security.h>
+#include <linux/evm.h>
#include <linux/syscalls.h>
#include <linux/module.h>
#include <linux/fsnotify.h>
}
EXPORT_SYMBOL_GPL(xattr_getsecurity);
+/*
+ * vfs_getxattr_alloc - allocate memory, if necessary, before calling getxattr
+ *
+ * Allocate memory, if not already allocated, or re-allocate correct size,
+ * before retrieving the extended attribute.
+ *
+ * Returns the result of alloc, if failed, or the getxattr operation.
+ */
+ssize_t
+vfs_getxattr_alloc(struct dentry *dentry, const char *name, char **xattr_value,
+ size_t xattr_size, gfp_t flags)
+{
+ struct inode *inode = dentry->d_inode;
+ char *value = *xattr_value;
+ int error;
+
+ error = xattr_permission(inode, name, MAY_READ);
+ if (error)
+ return error;
+
+ if (!inode->i_op->getxattr)
+ return -EOPNOTSUPP;
+
+ error = inode->i_op->getxattr(dentry, name, NULL, 0);
+ if (error < 0)
+ return error;
+
+ if (!value || (error > xattr_size)) {
+ value = krealloc(*xattr_value, error + 1, flags);
+ if (!value)
+ return -ENOMEM;
+ memset(value, 0, error + 1);
+ }
+
+ error = inode->i_op->getxattr(dentry, name, value, error);
+ *xattr_value = value;
+ return error;
+}
+
+/* Compare an extended attribute value with the given value */
+int vfs_xattr_cmp(struct dentry *dentry, const char *xattr_name,
+ const char *value, size_t size, gfp_t flags)
+{
+ char *xattr_value = NULL;
+ int rc;
+
+ rc = vfs_getxattr_alloc(dentry, xattr_name, &xattr_value, 0, flags);
+ if (rc < 0)
+ return rc;
+
+ if ((rc != size) || (memcmp(xattr_value, value, rc) != 0))
+ rc = -EINVAL;
+ else
+ rc = 0;
+ kfree(xattr_value);
+ return rc;
+}
+
ssize_t
vfs_getxattr(struct dentry *dentry, const char *name, void *value, size_t size)
{
error = inode->i_op->removexattr(dentry, name);
mutex_unlock(&inode->i_mutex);
- if (!error)
+ if (!error) {
fsnotify_xattr(dentry);
+ evm_inode_post_removexattr(dentry, name);
+ }
return error;
}
EXPORT_SYMBOL_GPL(vfs_removexattr);
mark_inode_dirty(inode);
}
+
+int xfs_initxattrs(struct inode *inode, const struct xattr *xattr_array,
+ void *fs_info)
+{
+ const struct xattr *xattr;
+ struct xfs_inode *ip = XFS_I(inode);
+ int error = 0;
+
+ for (xattr = xattr_array; xattr->name != NULL; xattr++) {
+ error = xfs_attr_set(ip, xattr->name, xattr->value,
+ xattr->value_len, ATTR_SECURE);
+ if (error < 0)
+ break;
+ }
+ return error;
+}
+
/*
* Hook in SELinux. This is not quite correct yet, what we really need
* here (as we do for default ACLs) is a mechanism by which creation of
* these attrs can be journalled at inode creation time (along with the
* inode, of course, such that log replay can't cause these to be lost).
*/
+
STATIC int
xfs_init_security(
struct inode *inode,
struct inode *dir,
const struct qstr *qstr)
{
- struct xfs_inode *ip = XFS_I(inode);
- size_t length;
- void *value;
- unsigned char *name;
- int error;
-
- error = security_inode_init_security(inode, dir, qstr, (char **)&name,
- &value, &length);
- if (error) {
- if (error == -EOPNOTSUPP)
- return 0;
- return -error;
- }
-
- error = xfs_attr_set(ip, name, value, length, ATTR_SECURE);
-
- kfree(name);
- kfree(value);
- return error;
+ return security_inode_init_security(inode, dir, qstr,
+ &xfs_initxattrs, NULL);
}
static void
--- /dev/null
+/*
+ * evm.h
+ *
+ * Copyright (c) 2009 IBM Corporation
+ * Author: Mimi Zohar <zohar@us.ibm.com>
+ */
+
+#ifndef _LINUX_EVM_H
+#define _LINUX_EVM_H
+
+#include <linux/integrity.h>
+#include <linux/xattr.h>
+
+struct integrity_iint_cache;
+
+#ifdef CONFIG_EVM
+extern enum integrity_status evm_verifyxattr(struct dentry *dentry,
+ const char *xattr_name,
+ void *xattr_value,
+ size_t xattr_value_len,
+ struct integrity_iint_cache *iint);
+extern int evm_inode_setattr(struct dentry *dentry, struct iattr *attr);
+extern void evm_inode_post_setattr(struct dentry *dentry, int ia_valid);
+extern int evm_inode_setxattr(struct dentry *dentry, const char *name,
+ const void *value, size_t size);
+extern void evm_inode_post_setxattr(struct dentry *dentry,
+ const char *xattr_name,
+ const void *xattr_value,
+ size_t xattr_value_len);
+extern int evm_inode_removexattr(struct dentry *dentry, const char *xattr_name);
+extern void evm_inode_post_removexattr(struct dentry *dentry,
+ const char *xattr_name);
+extern int evm_inode_init_security(struct inode *inode,
+ const struct xattr *xattr_array,
+ struct xattr *evm);
+#else
+#ifdef CONFIG_INTEGRITY
+static inline enum integrity_status evm_verifyxattr(struct dentry *dentry,
+ const char *xattr_name,
+ void *xattr_value,
+ size_t xattr_value_len,
+ struct integrity_iint_cache *iint)
+{
+ return INTEGRITY_UNKNOWN;
+}
+#endif
+
+static int evm_inode_setattr(struct dentry *dentry, struct iattr *attr)
+{
+ return 0;
+}
+
+static inline void evm_inode_post_setattr(struct dentry *dentry, int ia_valid)
+{
+ return;
+}
+
+static inline int evm_inode_setxattr(struct dentry *dentry, const char *name,
+ const void *value, size_t size)
+{
+ return 0;
+}
+
+static inline void evm_inode_post_setxattr(struct dentry *dentry,
+ const char *xattr_name,
+ const void *xattr_value,
+ size_t xattr_value_len)
+{
+ return;
+}
+
+static inline int evm_inode_removexattr(struct dentry *dentry,
+ const char *xattr_name)
+{
+ return 0;
+}
+
+static inline void evm_inode_post_removexattr(struct dentry *dentry,
+ const char *xattr_name)
+{
+ return;
+}
+
+static inline int evm_inode_init_security(struct inode *inode,
+ const struct xattr *xattr_array,
+ struct xattr *evm)
+{
+ return -EOPNOTSUPP;
+}
+
+#endif /* CONFIG_EVM_H */
+#endif /* LINUX_EVM_H */
#ifdef CONFIG_IMA
extern int ima_bprm_check(struct linux_binprm *bprm);
-extern int ima_inode_alloc(struct inode *inode);
-extern void ima_inode_free(struct inode *inode);
extern int ima_file_check(struct file *file, int mask);
extern void ima_file_free(struct file *file);
extern int ima_file_mmap(struct file *file, unsigned long prot);
return 0;
}
-static inline int ima_inode_alloc(struct inode *inode)
-{
- return 0;
-}
-
-static inline void ima_inode_free(struct inode *inode)
-{
- return;
-}
-
static inline int ima_file_check(struct file *file, int mask)
{
return 0;
{
return 0;
}
-
#endif /* CONFIG_IMA_H */
#endif /* _LINUX_IMA_H */
--- /dev/null
+/*
+ * Copyright (C) 2009 IBM Corporation
+ * Author: Mimi Zohar <zohar@us.ibm.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 of the License.
+ */
+
+#ifndef _LINUX_INTEGRITY_H
+#define _LINUX_INTEGRITY_H
+
+#include <linux/fs.h>
+
+enum integrity_status {
+ INTEGRITY_PASS = 0,
+ INTEGRITY_FAIL,
+ INTEGRITY_NOLABEL,
+ INTEGRITY_UNKNOWN,
+};
+
+/* List of EVM protected security xattrs */
+#ifdef CONFIG_INTEGRITY
+extern int integrity_inode_alloc(struct inode *inode);
+extern void integrity_inode_free(struct inode *inode);
+
+#else
+static inline int integrity_inode_alloc(struct inode *inode)
+{
+ return 0;
+}
+
+static inline void integrity_inode_free(struct inode *inode)
+{
+ return;
+}
+#endif /* CONFIG_INTEGRITY_H */
+#endif /* _LINUX_INTEGRITY_H */
#include <linux/key.h>
#include <linux/xfrm.h>
#include <linux/slab.h>
+#include <linux/xattr.h>
#include <net/flow.h>
/* Maximum number of letters for an LSM name string */
void __user *buffer, size_t *lenp, loff_t *ppos);
#endif
+/* security_inode_init_security callback function to write xattrs */
+typedef int (*initxattrs) (struct inode *inode,
+ const struct xattr *xattr_array, void *fs_data);
+
#ifdef CONFIG_SECURITY
struct security_mnt_opts {
int security_inode_alloc(struct inode *inode);
void security_inode_free(struct inode *inode);
int security_inode_init_security(struct inode *inode, struct inode *dir,
- const struct qstr *qstr, char **name,
- void **value, size_t *len);
+ const struct qstr *qstr,
+ initxattrs initxattrs, void *fs_data);
+int security_old_inode_init_security(struct inode *inode, struct inode *dir,
+ const struct qstr *qstr, char **name,
+ void **value, size_t *len);
int security_inode_create(struct inode *dir, struct dentry *dentry, int mode);
int security_inode_link(struct dentry *old_dentry, struct inode *dir,
struct dentry *new_dentry);
static inline int security_inode_init_security(struct inode *inode,
struct inode *dir,
const struct qstr *qstr,
- char **name,
- void **value,
- size_t *len)
+ initxattrs initxattrs,
+ void *fs_data)
{
return -EOPNOTSUPP;
}
#define XATTR_USER_PREFIX_LEN (sizeof (XATTR_USER_PREFIX) - 1)
/* Security namespace */
+#define XATTR_EVM_SUFFIX "evm"
+#define XATTR_NAME_EVM XATTR_SECURITY_PREFIX XATTR_EVM_SUFFIX
+
#define XATTR_SELINUX_SUFFIX "selinux"
#define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX
size_t size, int flags, int handler_flags);
};
+struct xattr {
+ char *name;
+ void *value;
+ size_t value_len;
+};
+
ssize_t xattr_getsecurity(struct inode *, const char *, void *, size_t);
ssize_t vfs_getxattr(struct dentry *, const char *, void *, size_t);
ssize_t vfs_listxattr(struct dentry *d, char *list, size_t size);
ssize_t generic_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size);
int generic_setxattr(struct dentry *dentry, const char *name, const void *value, size_t size, int flags);
int generic_removexattr(struct dentry *dentry, const char *name);
-
+ssize_t vfs_getxattr_alloc(struct dentry *dentry, const char *name,
+ char **xattr_value, size_t size, gfp_t flags);
+int vfs_xattr_cmp(struct dentry *dentry, const char *xattr_name,
+ const char *value, size_t size, gfp_t flags);
#endif /* __KERNEL__ */
#endif /* _LINUX_XATTR_H */
inode = shmem_get_inode(dir->i_sb, dir, mode, dev, VM_NORESERVE);
if (inode) {
error = security_inode_init_security(inode, dir,
- &dentry->d_name, NULL,
+ &dentry->d_name,
NULL, NULL);
if (error) {
if (error != -EOPNOTSUPP) {
if (!inode)
return -ENOSPC;
- error = security_inode_init_security(inode, dir, &dentry->d_name, NULL,
+ error = security_inode_init_security(inode, dir, &dentry->d_name,
NULL, NULL);
if (error) {
if (error != -EOPNOTSUPP) {
source security/tomoyo/Kconfig
source security/apparmor/Kconfig
-source security/integrity/ima/Kconfig
+source security/integrity/Kconfig
choice
prompt "Default security module"
obj-$(CONFIG_CGROUP_DEVICE) += device_cgroup.o
# Object integrity file lists
-subdir-$(CONFIG_IMA) += integrity/ima
-obj-$(CONFIG_IMA) += integrity/ima/built-in.o
+subdir-$(CONFIG_INTEGRITY) += integrity
+obj-$(CONFIG_INTEGRITY) += integrity/built-in.o
--- /dev/null
+#
+config INTEGRITY
+ def_bool y
+ depends on IMA || EVM
+
+source security/integrity/ima/Kconfig
+source security/integrity/evm/Kconfig
--- /dev/null
+#
+# Makefile for caching inode integrity data (iint)
+#
+
+obj-$(CONFIG_INTEGRITY) += integrity.o
+
+integrity-y := iint.o
+
+subdir-$(CONFIG_IMA) += ima
+obj-$(CONFIG_IMA) += ima/built-in.o
+subdir-$(CONFIG_EVM) += evm
+obj-$(CONFIG_EVM) += evm/built-in.o
--- /dev/null
+config EVM
+ boolean "EVM support"
+ depends on SECURITY && KEYS && ENCRYPTED_KEYS
+ select CRYPTO_HMAC
+ select CRYPTO_MD5
+ select CRYPTO_SHA1
+ default n
+ help
+ EVM protects a file's security extended attributes against
+ integrity attacks.
+
+ If you are unsure how to answer this question, answer N.
--- /dev/null
+#
+# Makefile for building the Extended Verification Module(EVM)
+#
+obj-$(CONFIG_EVM) += evm.o
+
+evm-y := evm_main.o evm_crypto.o evm_secfs.o
--- /dev/null
+/*
+ * Copyright (C) 2005-2010 IBM Corporation
+ *
+ * Authors:
+ * Mimi Zohar <zohar@us.ibm.com>
+ * Kylene Hall <kjhall@us.ibm.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 of the License.
+ *
+ * File: evm.h
+ *
+ */
+#include <linux/xattr.h>
+#include <linux/security.h>
+#include "../integrity.h"
+
+extern int evm_initialized;
+extern char *evm_hmac;
+
+extern struct crypto_shash *hmac_tfm;
+
+/* List of EVM protected security xattrs */
+extern char *evm_config_xattrnames[];
+
+extern int evm_init_key(void);
+extern int evm_update_evmxattr(struct dentry *dentry,
+ const char *req_xattr_name,
+ const char *req_xattr_value,
+ size_t req_xattr_value_len);
+extern int evm_calc_hmac(struct dentry *dentry, const char *req_xattr_name,
+ const char *req_xattr_value,
+ size_t req_xattr_value_len, char *digest);
+extern int evm_init_hmac(struct inode *inode, const struct xattr *xattr,
+ char *hmac_val);
+extern int evm_init_secfs(void);
+extern void evm_cleanup_secfs(void);
--- /dev/null
+/*
+ * Copyright (C) 2005-2010 IBM Corporation
+ *
+ * Authors:
+ * Mimi Zohar <zohar@us.ibm.com>
+ * Kylene Hall <kjhall@us.ibm.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 of the License.
+ *
+ * File: evm_crypto.c
+ * Using root's kernel master key (kmk), calculate the HMAC
+ */
+
+#include <linux/module.h>
+#include <linux/crypto.h>
+#include <linux/xattr.h>
+#include <keys/encrypted-type.h>
+#include <crypto/hash.h>
+#include "evm.h"
+
+#define EVMKEY "evm-key"
+#define MAX_KEY_SIZE 128
+static unsigned char evmkey[MAX_KEY_SIZE];
+static int evmkey_len = MAX_KEY_SIZE;
+
+struct crypto_shash *hmac_tfm;
+
+static struct shash_desc *init_desc(void)
+{
+ int rc;
+ struct shash_desc *desc;
+
+ if (hmac_tfm == NULL) {
+ hmac_tfm = crypto_alloc_shash(evm_hmac, 0, CRYPTO_ALG_ASYNC);
+ if (IS_ERR(hmac_tfm)) {
+ pr_err("Can not allocate %s (reason: %ld)\n",
+ evm_hmac, PTR_ERR(hmac_tfm));
+ rc = PTR_ERR(hmac_tfm);
+ hmac_tfm = NULL;
+ return ERR_PTR(rc);
+ }
+ }
+
+ desc = kmalloc(sizeof(*desc) + crypto_shash_descsize(hmac_tfm),
+ GFP_KERNEL);
+ if (!desc)
+ return ERR_PTR(-ENOMEM);
+
+ desc->tfm = hmac_tfm;
+ desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP;
+
+ rc = crypto_shash_setkey(hmac_tfm, evmkey, evmkey_len);
+ if (rc)
+ goto out;
+ rc = crypto_shash_init(desc);
+out:
+ if (rc) {
+ kfree(desc);
+ return ERR_PTR(rc);
+ }
+ return desc;
+}
+
+/* Protect against 'cutting & pasting' security.evm xattr, include inode
+ * specific info.
+ *
+ * (Additional directory/file metadata needs to be added for more complete
+ * protection.)
+ */
+static void hmac_add_misc(struct shash_desc *desc, struct inode *inode,
+ char *digest)
+{
+ struct h_misc {
+ unsigned long ino;
+ __u32 generation;
+ uid_t uid;
+ gid_t gid;
+ umode_t mode;
+ } hmac_misc;
+
+ memset(&hmac_misc, 0, sizeof hmac_misc);
+ hmac_misc.ino = inode->i_ino;
+ hmac_misc.generation = inode->i_generation;
+ hmac_misc.uid = inode->i_uid;
+ hmac_misc.gid = inode->i_gid;
+ hmac_misc.mode = inode->i_mode;
+ crypto_shash_update(desc, (const u8 *)&hmac_misc, sizeof hmac_misc);
+ crypto_shash_final(desc, digest);
+}
+
+/*
+ * Calculate the HMAC value across the set of protected security xattrs.
+ *
+ * Instead of retrieving the requested xattr, for performance, calculate
+ * the hmac using the requested xattr value. Don't alloc/free memory for
+ * each xattr, but attempt to re-use the previously allocated memory.
+ */
+int evm_calc_hmac(struct dentry *dentry, const char *req_xattr_name,
+ const char *req_xattr_value, size_t req_xattr_value_len,
+ char *digest)
+{
+ struct inode *inode = dentry->d_inode;
+ struct shash_desc *desc;
+ char **xattrname;
+ size_t xattr_size = 0;
+ char *xattr_value = NULL;
+ int error;
+ int size;
+
+ if (!inode->i_op || !inode->i_op->getxattr)
+ return -EOPNOTSUPP;
+ desc = init_desc();
+ if (IS_ERR(desc))
+ return PTR_ERR(desc);
+
+ error = -ENODATA;
+ for (xattrname = evm_config_xattrnames; *xattrname != NULL; xattrname++) {
+ if ((req_xattr_name && req_xattr_value)
+ && !strcmp(*xattrname, req_xattr_name)) {
+ error = 0;
+ crypto_shash_update(desc, (const u8 *)req_xattr_value,
+ req_xattr_value_len);
+ continue;
+ }
+ size = vfs_getxattr_alloc(dentry, *xattrname,
+ &xattr_value, xattr_size, GFP_NOFS);
+ if (size == -ENOMEM) {
+ error = -ENOMEM;
+ goto out;
+ }
+ if (size < 0)
+ continue;
+
+ error = 0;
+ xattr_size = size;
+ crypto_shash_update(desc, (const u8 *)xattr_value, xattr_size);
+ }
+ hmac_add_misc(desc, inode, digest);
+
+out:
+ kfree(xattr_value);
+ kfree(desc);
+ return error;
+}
+
+/*
+ * Calculate the hmac and update security.evm xattr
+ *
+ * Expects to be called with i_mutex locked.
+ */
+int evm_update_evmxattr(struct dentry *dentry, const char *xattr_name,
+ const char *xattr_value, size_t xattr_value_len)
+{
+ struct inode *inode = dentry->d_inode;
+ struct evm_ima_xattr_data xattr_data;
+ int rc = 0;
+
+ rc = evm_calc_hmac(dentry, xattr_name, xattr_value,
+ xattr_value_len, xattr_data.digest);
+ if (rc == 0) {
+ xattr_data.type = EVM_XATTR_HMAC;
+ rc = __vfs_setxattr_noperm(dentry, XATTR_NAME_EVM,
+ &xattr_data,
+ sizeof(xattr_data), 0);
+ }
+ else if (rc == -ENODATA)
+ rc = inode->i_op->removexattr(dentry, XATTR_NAME_EVM);
+ return rc;
+}
+
+int evm_init_hmac(struct inode *inode, const struct xattr *lsm_xattr,
+ char *hmac_val)
+{
+ struct shash_desc *desc;
+
+ desc = init_desc();
+ if (IS_ERR(desc)) {
+ printk(KERN_INFO "init_desc failed\n");
+ return PTR_ERR(desc);
+ }
+
+ crypto_shash_update(desc, lsm_xattr->value, lsm_xattr->value_len);
+ hmac_add_misc(desc, inode, hmac_val);
+ kfree(desc);
+ return 0;
+}
+
+/*
+ * Get the key from the TPM for the SHA1-HMAC
+ */
+int evm_init_key(void)
+{
+ struct key *evm_key;
+ struct encrypted_key_payload *ekp;
+ int rc = 0;
+
+ evm_key = request_key(&key_type_encrypted, EVMKEY, NULL);
+ if (IS_ERR(evm_key))
+ return -ENOENT;
+
+ down_read(&evm_key->sem);
+ ekp = evm_key->payload.data;
+ if (ekp->decrypted_datalen > MAX_KEY_SIZE) {
+ rc = -EINVAL;
+ goto out;
+ }
+ memcpy(evmkey, ekp->decrypted_data, ekp->decrypted_datalen);
+out:
+ /* burn the original key contents */
+ memset(ekp->decrypted_data, 0, ekp->decrypted_datalen);
+ up_read(&evm_key->sem);
+ key_put(evm_key);
+ return rc;
+}
--- /dev/null
+/*
+ * Copyright (C) 2005-2010 IBM Corporation
+ *
+ * Author:
+ * Mimi Zohar <zohar@us.ibm.com>
+ * Kylene Hall <kjhall@us.ibm.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 of the License.
+ *
+ * File: evm_main.c
+ * implements evm_inode_setxattr, evm_inode_post_setxattr,
+ * evm_inode_removexattr, and evm_verifyxattr
+ */
+
+#include <linux/module.h>
+#include <linux/crypto.h>
+#include <linux/xattr.h>
+#include <linux/integrity.h>
+#include <linux/evm.h>
+#include <crypto/hash.h>
+#include "evm.h"
+
+int evm_initialized;
+
+char *evm_hmac = "hmac(sha1)";
+
+char *evm_config_xattrnames[] = {
+#ifdef CONFIG_SECURITY_SELINUX
+ XATTR_NAME_SELINUX,
+#endif
+#ifdef CONFIG_SECURITY_SMACK
+ XATTR_NAME_SMACK,
+#endif
+ XATTR_NAME_CAPS,
+ NULL
+};
+
+static int evm_fixmode;
+static int __init evm_set_fixmode(char *str)
+{
+ if (strncmp(str, "fix", 3) == 0)
+ evm_fixmode = 1;
+ return 0;
+}
+__setup("evm=", evm_set_fixmode);
+
+/*
+ * evm_verify_hmac - calculate and compare the HMAC with the EVM xattr
+ *
+ * Compute the HMAC on the dentry's protected set of extended attributes
+ * and compare it against the stored security.evm xattr.
+ *
+ * For performance:
+ * - use the previoulsy retrieved xattr value and length to calculate the
+ * HMAC.)
+ * - cache the verification result in the iint, when available.
+ *
+ * Returns integrity status
+ */
+static enum integrity_status evm_verify_hmac(struct dentry *dentry,
+ const char *xattr_name,
+ char *xattr_value,
+ size_t xattr_value_len,
+ struct integrity_iint_cache *iint)
+{
+ struct evm_ima_xattr_data xattr_data;
+ enum integrity_status evm_status;
+ int rc;
+
+ if (iint && iint->evm_status == INTEGRITY_PASS)
+ return iint->evm_status;
+
+ /* if status is not PASS, try to check again - against -ENOMEM */
+
+ rc = evm_calc_hmac(dentry, xattr_name, xattr_value,
+ xattr_value_len, xattr_data.digest);
+ if (rc < 0)
+ goto err_out;
+
+ xattr_data.type = EVM_XATTR_HMAC;
+ rc = vfs_xattr_cmp(dentry, XATTR_NAME_EVM, (u8 *)&xattr_data,
+ sizeof xattr_data, GFP_NOFS);
+ if (rc < 0)
+ goto err_out;
+ evm_status = INTEGRITY_PASS;
+ goto out;
+
+err_out:
+ switch (rc) {
+ case -ENODATA: /* file not labelled */
+ evm_status = INTEGRITY_NOLABEL;
+ break;
+ default:
+ evm_status = INTEGRITY_FAIL;
+ }
+out:
+ if (iint)
+ iint->evm_status = evm_status;
+ return evm_status;
+}
+
+static int evm_protected_xattr(const char *req_xattr_name)
+{
+ char **xattrname;
+ int namelen;
+ int found = 0;
+
+ namelen = strlen(req_xattr_name);
+ for (xattrname = evm_config_xattrnames; *xattrname != NULL; xattrname++) {
+ if ((strlen(*xattrname) == namelen)
+ && (strncmp(req_xattr_name, *xattrname, namelen) == 0)) {
+ found = 1;
+ break;
+ }
+ if (strncmp(req_xattr_name,
+ *xattrname + XATTR_SECURITY_PREFIX_LEN,
+ strlen(req_xattr_name)) == 0) {
+ found = 1;
+ break;
+ }
+ }
+ return found;
+}
+
+/**
+ * evm_verifyxattr - verify the integrity of the requested xattr
+ * @dentry: object of the verify xattr
+ * @xattr_name: requested xattr
+ * @xattr_value: requested xattr value
+ * @xattr_value_len: requested xattr value length
+ *
+ * Calculate the HMAC for the given dentry and verify it against the stored
+ * security.evm xattr. For performance, use the xattr value and length
+ * previously retrieved to calculate the HMAC.
+ *
+ * Returns the xattr integrity status.
+ *
+ * This function requires the caller to lock the inode's i_mutex before it
+ * is executed.
+ */
+enum integrity_status evm_verifyxattr(struct dentry *dentry,
+ const char *xattr_name,
+ void *xattr_value, size_t xattr_value_len,
+ struct integrity_iint_cache *iint)
+{
+ if (!evm_initialized || !evm_protected_xattr(xattr_name))
+ return INTEGRITY_UNKNOWN;
+
+ if (!iint) {
+ iint = integrity_iint_find(dentry->d_inode);
+ if (!iint)
+ return INTEGRITY_UNKNOWN;
+ }
+ return evm_verify_hmac(dentry, xattr_name, xattr_value,
+ xattr_value_len, iint);
+}
+EXPORT_SYMBOL_GPL(evm_verifyxattr);
+
+/*
+ * evm_protect_xattr - protect the EVM extended attribute
+ *
+ * Prevent security.evm from being modified or removed.
+ */
+static int evm_protect_xattr(struct dentry *dentry, const char *xattr_name,
+ const void *xattr_value, size_t xattr_value_len)
+{
+ if (strcmp(xattr_name, XATTR_NAME_EVM) == 0) {
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+ }
+ return 0;
+}
+
+/*
+ * evm_verify_current_integrity - verify the dentry's metadata integrity
+ * @dentry: pointer to the affected dentry
+ *
+ * Verify and return the dentry's metadata integrity. The exceptions are
+ * before EVM is initialized or in 'fix' mode.
+ */
+static enum integrity_status evm_verify_current_integrity(struct dentry *dentry)
+{
+ struct inode *inode = dentry->d_inode;
+
+ if (!evm_initialized || !S_ISREG(inode->i_mode) || evm_fixmode)
+ return 0;
+ return evm_verify_hmac(dentry, NULL, NULL, 0, NULL);
+}
+
+/**
+ * evm_inode_setxattr - protect the EVM extended attribute
+ * @dentry: pointer to the affected dentry
+ * @xattr_name: pointer to the affected extended attribute name
+ * @xattr_value: pointer to the new extended attribute value
+ * @xattr_value_len: pointer to the new extended attribute value length
+ *
+ * Updating 'security.evm' requires CAP_SYS_ADMIN privileges and that
+ * the current value is valid.
+ */
+int evm_inode_setxattr(struct dentry *dentry, const char *xattr_name,
+ const void *xattr_value, size_t xattr_value_len)
+{
+
+ enum integrity_status evm_status;
+ int ret;
+
+ ret = evm_protect_xattr(dentry, xattr_name, xattr_value,
+ xattr_value_len);
+ if (ret)
+ return ret;
+ evm_status = evm_verify_current_integrity(dentry);
+ return evm_status == INTEGRITY_PASS ? 0 : -EPERM;
+}
+
+/**
+ * evm_inode_removexattr - protect the EVM extended attribute
+ * @dentry: pointer to the affected dentry
+ * @xattr_name: pointer to the affected extended attribute name
+ *
+ * Removing 'security.evm' requires CAP_SYS_ADMIN privileges and that
+ * the current value is valid.
+ */
+int evm_inode_removexattr(struct dentry *dentry, const char *xattr_name)
+{
+ enum integrity_status evm_status;
+ int ret;
+
+ ret = evm_protect_xattr(dentry, xattr_name, NULL, 0);
+ if (ret)
+ return ret;
+ evm_status = evm_verify_current_integrity(dentry);
+ return evm_status == INTEGRITY_PASS ? 0 : -EPERM;
+}
+
+/**
+ * evm_inode_post_setxattr - update 'security.evm' to reflect the changes
+ * @dentry: pointer to the affected dentry
+ * @xattr_name: pointer to the affected extended attribute name
+ * @xattr_value: pointer to the new extended attribute value
+ * @xattr_value_len: pointer to the new extended attribute value length
+ *
+ * Update the HMAC stored in 'security.evm' to reflect the change.
+ *
+ * No need to take the i_mutex lock here, as this function is called from
+ * __vfs_setxattr_noperm(). The caller of which has taken the inode's
+ * i_mutex lock.
+ */
+void evm_inode_post_setxattr(struct dentry *dentry, const char *xattr_name,
+ const void *xattr_value, size_t xattr_value_len)
+{
+ if (!evm_initialized || !evm_protected_xattr(xattr_name))
+ return;
+
+ evm_update_evmxattr(dentry, xattr_name, xattr_value, xattr_value_len);
+ return;
+}
+
+/**
+ * evm_inode_post_removexattr - update 'security.evm' after removing the xattr
+ * @dentry: pointer to the affected dentry
+ * @xattr_name: pointer to the affected extended attribute name
+ *
+ * Update the HMAC stored in 'security.evm' to reflect removal of the xattr.
+ */
+void evm_inode_post_removexattr(struct dentry *dentry, const char *xattr_name)
+{
+ struct inode *inode = dentry->d_inode;
+
+ if (!evm_initialized || !evm_protected_xattr(xattr_name))
+ return;
+
+ mutex_lock(&inode->i_mutex);
+ evm_update_evmxattr(dentry, xattr_name, NULL, 0);
+ mutex_unlock(&inode->i_mutex);
+ return;
+}
+
+/**
+ * evm_inode_setattr - prevent updating an invalid EVM extended attribute
+ * @dentry: pointer to the affected dentry
+ */
+int evm_inode_setattr(struct dentry *dentry, struct iattr *attr)
+{
+ unsigned int ia_valid = attr->ia_valid;
+ enum integrity_status evm_status;
+
+ if (ia_valid & ~(ATTR_MODE | ATTR_UID | ATTR_GID))
+ return 0;
+ evm_status = evm_verify_current_integrity(dentry);
+ return evm_status == INTEGRITY_PASS ? 0 : -EPERM;
+}
+
+/**
+ * evm_inode_post_setattr - update 'security.evm' after modifying metadata
+ * @dentry: pointer to the affected dentry
+ * @ia_valid: for the UID and GID status
+ *
+ * For now, update the HMAC stored in 'security.evm' to reflect UID/GID
+ * changes.
+ *
+ * This function is called from notify_change(), which expects the caller
+ * to lock the inode's i_mutex.
+ */
+void evm_inode_post_setattr(struct dentry *dentry, int ia_valid)
+{
+ if (!evm_initialized)
+ return;
+
+ if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID))
+ evm_update_evmxattr(dentry, NULL, NULL, 0);
+ return;
+}
+
+/*
+ * evm_inode_init_security - initializes security.evm
+ */
+int evm_inode_init_security(struct inode *inode,
+ const struct xattr *lsm_xattr,
+ struct xattr *evm_xattr)
+{
+ struct evm_ima_xattr_data *xattr_data;
+ int rc;
+
+ if (!evm_initialized || !evm_protected_xattr(lsm_xattr->name))
+ return -EOPNOTSUPP;
+
+ xattr_data = kzalloc(sizeof(*xattr_data), GFP_NOFS);
+ if (!xattr_data)
+ return -ENOMEM;
+
+ xattr_data->type = EVM_XATTR_HMAC;
+ rc = evm_init_hmac(inode, lsm_xattr, xattr_data->digest);
+ if (rc < 0)
+ goto out;
+
+ evm_xattr->value = xattr_data;
+ evm_xattr->value_len = sizeof(*xattr_data);
+ evm_xattr->name = kstrdup(XATTR_EVM_SUFFIX, GFP_NOFS);
+ return 0;
+out:
+ kfree(xattr_data);
+ return rc;
+}
+EXPORT_SYMBOL_GPL(evm_inode_init_security);
+
+static int __init init_evm(void)
+{
+ int error;
+
+ error = evm_init_secfs();
+ if (error < 0) {
+ printk(KERN_INFO "EVM: Error registering secfs\n");
+ goto err;
+ }
+err:
+ return error;
+}
+
+static void __exit cleanup_evm(void)
+{
+ evm_cleanup_secfs();
+ if (hmac_tfm)
+ crypto_free_shash(hmac_tfm);
+}
+
+/*
+ * evm_display_config - list the EVM protected security extended attributes
+ */
+static int __init evm_display_config(void)
+{
+ char **xattrname;
+
+ for (xattrname = evm_config_xattrnames; *xattrname != NULL; xattrname++)
+ printk(KERN_INFO "EVM: %s\n", *xattrname);
+ return 0;
+}
+
+pure_initcall(evm_display_config);
+late_initcall(init_evm);
+
+MODULE_DESCRIPTION("Extended Verification Module");
+MODULE_LICENSE("GPL");
--- /dev/null
+/*
+ * Copyright (C) 2010 IBM Corporation
+ *
+ * Authors:
+ * Mimi Zohar <zohar@us.ibm.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 of the License.
+ *
+ * File: evm_secfs.c
+ * - Used to signal when key is on keyring
+ * - Get the key and enable EVM
+ */
+
+#include <linux/uaccess.h>
+#include <linux/module.h>
+#include "evm.h"
+
+static struct dentry *evm_init_tpm;
+
+/**
+ * evm_read_key - read() for <securityfs>/evm
+ *
+ * @filp: file pointer, not actually used
+ * @buf: where to put the result
+ * @count: maximum to send along
+ * @ppos: where to start
+ *
+ * Returns number of bytes read or error code, as appropriate
+ */
+static ssize_t evm_read_key(struct file *filp, char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ char temp[80];
+ ssize_t rc;
+
+ if (*ppos != 0)
+ return 0;
+
+ sprintf(temp, "%d", evm_initialized);
+ rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp));
+
+ return rc;
+}
+
+/**
+ * evm_write_key - write() for <securityfs>/evm
+ * @file: file pointer, not actually used
+ * @buf: where to get the data from
+ * @count: bytes sent
+ * @ppos: where to start
+ *
+ * Used to signal that key is on the kernel key ring.
+ * - get the integrity hmac key from the kernel key ring
+ * - create list of hmac protected extended attributes
+ * Returns number of bytes written or error code, as appropriate
+ */
+static ssize_t evm_write_key(struct file *file, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ char temp[80];
+ int i, error;
+
+ if (!capable(CAP_SYS_ADMIN) || evm_initialized)
+ return -EPERM;
+
+ if (count >= sizeof(temp) || count == 0)
+ return -EINVAL;
+
+ if (copy_from_user(temp, buf, count) != 0)
+ return -EFAULT;
+
+ temp[count] = '\0';
+
+ if ((sscanf(temp, "%d", &i) != 1) || (i != 1))
+ return -EINVAL;
+
+ error = evm_init_key();
+ if (!error) {
+ evm_initialized = 1;
+ pr_info("EVM: initialized\n");
+ } else
+ pr_err("EVM: initialization failed\n");
+ return count;
+}
+
+static const struct file_operations evm_key_ops = {
+ .read = evm_read_key,
+ .write = evm_write_key,
+};
+
+int __init evm_init_secfs(void)
+{
+ int error = 0;
+
+ evm_init_tpm = securityfs_create_file("evm", S_IRUSR | S_IRGRP,
+ NULL, NULL, &evm_key_ops);
+ if (!evm_init_tpm || IS_ERR(evm_init_tpm))
+ error = -EFAULT;
+ return error;
+}
+
+void __exit evm_cleanup_secfs(void)
+{
+ if (evm_init_tpm)
+ securityfs_remove(evm_init_tpm);
+}
--- /dev/null
+/*
+ * Copyright (C) 2008 IBM Corporation
+ *
+ * Authors:
+ * Mimi Zohar <zohar@us.ibm.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 of the
+ * License.
+ *
+ * File: integrity_iint.c
+ * - implements the integrity hooks: integrity_inode_alloc,
+ * integrity_inode_free
+ * - cache integrity information associated with an inode
+ * using a rbtree tree.
+ */
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/spinlock.h>
+#include <linux/rbtree.h>
+#include "integrity.h"
+
+static struct rb_root integrity_iint_tree = RB_ROOT;
+static DEFINE_SPINLOCK(integrity_iint_lock);
+static struct kmem_cache *iint_cache __read_mostly;
+
+int iint_initialized;
+
+/*
+ * __integrity_iint_find - return the iint associated with an inode
+ */
+static struct integrity_iint_cache *__integrity_iint_find(struct inode *inode)
+{
+ struct integrity_iint_cache *iint;
+ struct rb_node *n = integrity_iint_tree.rb_node;
+
+ assert_spin_locked(&integrity_iint_lock);
+
+ while (n) {
+ iint = rb_entry(n, struct integrity_iint_cache, rb_node);
+
+ if (inode < iint->inode)
+ n = n->rb_left;
+ else if (inode > iint->inode)
+ n = n->rb_right;
+ else
+ break;
+ }
+ if (!n)
+ return NULL;
+
+ return iint;
+}
+
+/*
+ * integrity_iint_find - return the iint associated with an inode
+ */
+struct integrity_iint_cache *integrity_iint_find(struct inode *inode)
+{
+ struct integrity_iint_cache *iint;
+
+ if (!IS_IMA(inode))
+ return NULL;
+
+ spin_lock(&integrity_iint_lock);
+ iint = __integrity_iint_find(inode);
+ spin_unlock(&integrity_iint_lock);
+
+ return iint;
+}
+
+static void iint_free(struct integrity_iint_cache *iint)
+{
+ iint->version = 0;
+ iint->flags = 0UL;
+ kmem_cache_free(iint_cache, iint);
+}
+
+/**
+ * integrity_inode_alloc - allocate an iint associated with an inode
+ * @inode: pointer to the inode
+ */
+int integrity_inode_alloc(struct inode *inode)
+{
+ struct rb_node **p;
+ struct rb_node *new_node, *parent = NULL;
+ struct integrity_iint_cache *new_iint, *test_iint;
+ int rc;
+
+ new_iint = kmem_cache_alloc(iint_cache, GFP_NOFS);
+ if (!new_iint)
+ return -ENOMEM;
+
+ new_iint->inode = inode;
+ new_node = &new_iint->rb_node;
+
+ mutex_lock(&inode->i_mutex); /* i_flags */
+ spin_lock(&integrity_iint_lock);
+
+ p = &integrity_iint_tree.rb_node;
+ while (*p) {
+ parent = *p;
+ test_iint = rb_entry(parent, struct integrity_iint_cache,
+ rb_node);
+ rc = -EEXIST;
+ if (inode < test_iint->inode)
+ p = &(*p)->rb_left;
+ else if (inode > test_iint->inode)
+ p = &(*p)->rb_right;
+ else
+ goto out_err;
+ }
+
+ inode->i_flags |= S_IMA;
+ rb_link_node(new_node, parent, p);
+ rb_insert_color(new_node, &integrity_iint_tree);
+
+ spin_unlock(&integrity_iint_lock);
+ mutex_unlock(&inode->i_mutex); /* i_flags */
+
+ return 0;
+out_err:
+ spin_unlock(&integrity_iint_lock);
+ mutex_unlock(&inode->i_mutex); /* i_flags */
+ iint_free(new_iint);
+
+ return rc;
+}
+
+/**
+ * integrity_inode_free - called on security_inode_free
+ * @inode: pointer to the inode
+ *
+ * Free the integrity information(iint) associated with an inode.
+ */
+void integrity_inode_free(struct inode *inode)
+{
+ struct integrity_iint_cache *iint;
+
+ if (!IS_IMA(inode))
+ return;
+
+ spin_lock(&integrity_iint_lock);
+ iint = __integrity_iint_find(inode);
+ rb_erase(&iint->rb_node, &integrity_iint_tree);
+ spin_unlock(&integrity_iint_lock);
+
+ iint_free(iint);
+}
+
+static void init_once(void *foo)
+{
+ struct integrity_iint_cache *iint = foo;
+
+ memset(iint, 0, sizeof *iint);
+ iint->version = 0;
+ iint->flags = 0UL;
+ mutex_init(&iint->mutex);
+ iint->evm_status = INTEGRITY_UNKNOWN;
+}
+
+static int __init integrity_iintcache_init(void)
+{
+ iint_cache =
+ kmem_cache_create("iint_cache", sizeof(struct integrity_iint_cache),
+ 0, SLAB_PANIC, init_once);
+ iint_initialized = 1;
+ return 0;
+}
+security_initcall(integrity_iintcache_init);
config IMA
bool "Integrity Measurement Architecture(IMA)"
depends on SECURITY
+ select INTEGRITY
select SECURITYFS
select CRYPTO
select CRYPTO_HMAC
obj-$(CONFIG_IMA) += ima.o
ima-y := ima_fs.o ima_queue.o ima_init.o ima_main.o ima_crypto.o ima_api.o \
- ima_policy.o ima_iint.o ima_audit.o
+ ima_policy.o ima_audit.o
#include <linux/tpm.h>
#include <linux/audit.h>
+#include "../integrity.h"
+
enum ima_show_type { IMA_SHOW_BINARY, IMA_SHOW_ASCII };
enum tpm_pcrs { TPM_PCR0 = 0, TPM_PCR8 = 8 };
/* digest size for IMA, fits SHA1 or MD5 */
-#define IMA_DIGEST_SIZE 20
+#define IMA_DIGEST_SIZE SHA1_DIGEST_SIZE
#define IMA_EVENT_NAME_LEN_MAX 255
#define IMA_HASH_BITS 9
return hash_long(*digest, IMA_HASH_BITS);
}
-/* iint cache flags */
-#define IMA_MEASURED 0x01
-
-/* integrity data associated with an inode */
-struct ima_iint_cache {
- struct rb_node rb_node; /* rooted in ima_iint_tree */
- struct inode *inode; /* back pointer to inode in question */
- u64 version; /* track inode changes */
- unsigned char flags;
- u8 digest[IMA_DIGEST_SIZE];
- struct mutex mutex; /* protects: version, flags, digest */
-};
-
/* LIM API function definitions */
int ima_must_measure(struct inode *inode, int mask, int function);
-int ima_collect_measurement(struct ima_iint_cache *iint, struct file *file);
-void ima_store_measurement(struct ima_iint_cache *iint, struct file *file,
+int ima_collect_measurement(struct integrity_iint_cache *iint,
+ struct file *file);
+void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file,
const unsigned char *filename);
int ima_store_template(struct ima_template_entry *entry, int violation,
struct inode *inode);
-void ima_template_show(struct seq_file *m, void *e,
- enum ima_show_type show);
+void ima_template_show(struct seq_file *m, void *e, enum ima_show_type show);
/* rbtree tree calls to lookup, insert, delete
* integrity data associated with an inode.
*/
-struct ima_iint_cache *ima_iint_insert(struct inode *inode);
-struct ima_iint_cache *ima_iint_find(struct inode *inode);
+struct integrity_iint_cache *integrity_iint_insert(struct inode *inode);
+struct integrity_iint_cache *integrity_iint_find(struct inode *inode);
/* IMA policy related functions */
enum ima_hooks { FILE_CHECK = 1, FILE_MMAP, BPRM_CHECK };
*
* Return 0 on success, error code otherwise
*/
-int ima_collect_measurement(struct ima_iint_cache *iint, struct file *file)
+int ima_collect_measurement(struct integrity_iint_cache *iint,
+ struct file *file)
{
int result = -EEXIST;
*
* Must be called with iint->mutex held.
*/
-void ima_store_measurement(struct ima_iint_cache *iint, struct file *file,
- const unsigned char *filename)
+void ima_store_measurement(struct integrity_iint_cache *iint,
+ struct file *file, const unsigned char *filename)
{
const char *op = "add_template_measure";
const char *audit_cause = "ENOMEM";
+++ /dev/null
-/*
- * Copyright (C) 2008 IBM Corporation
- *
- * Authors:
- * Mimi Zohar <zohar@us.ibm.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 of the
- * License.
- *
- * File: ima_iint.c
- * - implements the IMA hooks: ima_inode_alloc, ima_inode_free
- * - cache integrity information associated with an inode
- * using a rbtree tree.
- */
-#include <linux/slab.h>
-#include <linux/module.h>
-#include <linux/spinlock.h>
-#include <linux/rbtree.h>
-#include "ima.h"
-
-static struct rb_root ima_iint_tree = RB_ROOT;
-static DEFINE_SPINLOCK(ima_iint_lock);
-static struct kmem_cache *iint_cache __read_mostly;
-
-int iint_initialized = 0;
-
-/*
- * __ima_iint_find - return the iint associated with an inode
- */
-static struct ima_iint_cache *__ima_iint_find(struct inode *inode)
-{
- struct ima_iint_cache *iint;
- struct rb_node *n = ima_iint_tree.rb_node;
-
- assert_spin_locked(&ima_iint_lock);
-
- while (n) {
- iint = rb_entry(n, struct ima_iint_cache, rb_node);
-
- if (inode < iint->inode)
- n = n->rb_left;
- else if (inode > iint->inode)
- n = n->rb_right;
- else
- break;
- }
- if (!n)
- return NULL;
-
- return iint;
-}
-
-/*
- * ima_iint_find - return the iint associated with an inode
- */
-struct ima_iint_cache *ima_iint_find(struct inode *inode)
-{
- struct ima_iint_cache *iint;
-
- if (!IS_IMA(inode))
- return NULL;
-
- spin_lock(&ima_iint_lock);
- iint = __ima_iint_find(inode);
- spin_unlock(&ima_iint_lock);
-
- return iint;
-}
-
-static void iint_free(struct ima_iint_cache *iint)
-{
- iint->version = 0;
- iint->flags = 0UL;
- kmem_cache_free(iint_cache, iint);
-}
-
-/**
- * ima_inode_alloc - allocate an iint associated with an inode
- * @inode: pointer to the inode
- */
-int ima_inode_alloc(struct inode *inode)
-{
- struct rb_node **p;
- struct rb_node *new_node, *parent = NULL;
- struct ima_iint_cache *new_iint, *test_iint;
- int rc;
-
- new_iint = kmem_cache_alloc(iint_cache, GFP_NOFS);
- if (!new_iint)
- return -ENOMEM;
-
- new_iint->inode = inode;
- new_node = &new_iint->rb_node;
-
- mutex_lock(&inode->i_mutex); /* i_flags */
- spin_lock(&ima_iint_lock);
-
- p = &ima_iint_tree.rb_node;
- while (*p) {
- parent = *p;
- test_iint = rb_entry(parent, struct ima_iint_cache, rb_node);
-
- rc = -EEXIST;
- if (inode < test_iint->inode)
- p = &(*p)->rb_left;
- else if (inode > test_iint->inode)
- p = &(*p)->rb_right;
- else
- goto out_err;
- }
-
- inode->i_flags |= S_IMA;
- rb_link_node(new_node, parent, p);
- rb_insert_color(new_node, &ima_iint_tree);
-
- spin_unlock(&ima_iint_lock);
- mutex_unlock(&inode->i_mutex); /* i_flags */
-
- return 0;
-out_err:
- spin_unlock(&ima_iint_lock);
- mutex_unlock(&inode->i_mutex); /* i_flags */
- iint_free(new_iint);
-
- return rc;
-}
-
-/**
- * ima_inode_free - called on security_inode_free
- * @inode: pointer to the inode
- *
- * Free the integrity information(iint) associated with an inode.
- */
-void ima_inode_free(struct inode *inode)
-{
- struct ima_iint_cache *iint;
-
- if (!IS_IMA(inode))
- return;
-
- spin_lock(&ima_iint_lock);
- iint = __ima_iint_find(inode);
- rb_erase(&iint->rb_node, &ima_iint_tree);
- spin_unlock(&ima_iint_lock);
-
- iint_free(iint);
-}
-
-static void init_once(void *foo)
-{
- struct ima_iint_cache *iint = foo;
-
- memset(iint, 0, sizeof *iint);
- iint->version = 0;
- iint->flags = 0UL;
- mutex_init(&iint->mutex);
-}
-
-static int __init ima_iintcache_init(void)
-{
- iint_cache =
- kmem_cache_create("iint_cache", sizeof(struct ima_iint_cache), 0,
- SLAB_PANIC, init_once);
- iint_initialized = 1;
- return 0;
-}
-security_initcall(ima_iintcache_init);
"open_writers");
}
-static void ima_check_last_writer(struct ima_iint_cache *iint,
+static void ima_check_last_writer(struct integrity_iint_cache *iint,
struct inode *inode,
struct file *file)
{
void ima_file_free(struct file *file)
{
struct inode *inode = file->f_dentry->d_inode;
- struct ima_iint_cache *iint;
+ struct integrity_iint_cache *iint;
if (!iint_initialized || !S_ISREG(inode->i_mode))
return;
- iint = ima_iint_find(inode);
+ iint = integrity_iint_find(inode);
if (!iint)
return;
int mask, int function)
{
struct inode *inode = file->f_dentry->d_inode;
- struct ima_iint_cache *iint;
+ struct integrity_iint_cache *iint;
int rc = 0;
if (!ima_initialized || !S_ISREG(inode->i_mode))
if (rc != 0)
return rc;
retry:
- iint = ima_iint_find(inode);
+ iint = integrity_iint_find(inode);
if (!iint) {
- rc = ima_inode_alloc(inode);
+ rc = integrity_inode_alloc(inode);
if (!rc || rc == -EEXIST)
goto retry;
return rc;
--- /dev/null
+/*
+ * Copyright (C) 2009-2010 IBM Corporation
+ *
+ * Authors:
+ * Mimi Zohar <zohar@us.ibm.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 of the
+ * License.
+ *
+ */
+
+#include <linux/types.h>
+#include <linux/integrity.h>
+#include <crypto/sha.h>
+
+/* iint cache flags */
+#define IMA_MEASURED 0x01
+
+enum evm_ima_xattr_type {
+ IMA_XATTR_DIGEST = 0x01,
+ EVM_XATTR_HMAC,
+ EVM_IMA_XATTR_DIGSIG,
+};
+
+struct evm_ima_xattr_data {
+ u8 type;
+ u8 digest[SHA1_DIGEST_SIZE];
+} __attribute__((packed));
+
+/* integrity data associated with an inode */
+struct integrity_iint_cache {
+ struct rb_node rb_node; /* rooted in integrity_iint_tree */
+ struct inode *inode; /* back pointer to inode in question */
+ u64 version; /* track inode changes */
+ unsigned char flags;
+ u8 digest[SHA1_DIGEST_SIZE];
+ struct mutex mutex; /* protects: version, flags, digest */
+ enum integrity_status evm_status;
+};
+
+/* rbtree tree calls to lookup, insert, delete
+ * integrity data associated with an inode.
+ */
+struct integrity_iint_cache *integrity_iint_insert(struct inode *inode);
+struct integrity_iint_cache *integrity_iint_find(struct inode *inode);
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/security.h>
+#include <linux/integrity.h>
#include <linux/ima.h>
+#include <linux/evm.h>
+
+#define MAX_LSM_EVM_XATTR 2
/* Boot-time LSM user choice */
static __initdata char chosen_lsm[SECURITY_NAME_MAX + 1] =
void security_inode_free(struct inode *inode)
{
- ima_inode_free(inode);
+ integrity_inode_free(inode);
security_ops->inode_free_security(inode);
}
int security_inode_init_security(struct inode *inode, struct inode *dir,
- const struct qstr *qstr, char **name,
- void **value, size_t *len)
+ const struct qstr *qstr,
+ const initxattrs initxattrs, void *fs_data)
+{
+ struct xattr new_xattrs[MAX_LSM_EVM_XATTR + 1];
+ struct xattr *lsm_xattr, *evm_xattr, *xattr;
+ int ret;
+
+ if (unlikely(IS_PRIVATE(inode)))
+ return -EOPNOTSUPP;
+
+ memset(new_xattrs, 0, sizeof new_xattrs);
+ if (!initxattrs)
+ return security_ops->inode_init_security(inode, dir, qstr,
+ NULL, NULL, NULL);
+ lsm_xattr = new_xattrs;
+ ret = security_ops->inode_init_security(inode, dir, qstr,
+ &lsm_xattr->name,
+ &lsm_xattr->value,
+ &lsm_xattr->value_len);
+ if (ret)
+ goto out;
+
+ evm_xattr = lsm_xattr + 1;
+ ret = evm_inode_init_security(inode, lsm_xattr, evm_xattr);
+ if (ret)
+ goto out;
+ ret = initxattrs(inode, new_xattrs, fs_data);
+out:
+ for (xattr = new_xattrs; xattr->name != NULL; xattr++) {
+ kfree(xattr->name);
+ kfree(xattr->value);
+ }
+ return (ret == -EOPNOTSUPP) ? 0 : ret;
+}
+EXPORT_SYMBOL(security_inode_init_security);
+
+int security_old_inode_init_security(struct inode *inode, struct inode *dir,
+ const struct qstr *qstr, char **name,
+ void **value, size_t *len)
{
if (unlikely(IS_PRIVATE(inode)))
return -EOPNOTSUPP;
return security_ops->inode_init_security(inode, dir, qstr, name, value,
len);
}
-EXPORT_SYMBOL(security_inode_init_security);
+EXPORT_SYMBOL(security_old_inode_init_security);
#ifdef CONFIG_SECURITY_PATH
int security_path_mknod(struct path *dir, struct dentry *dentry, int mode,
int security_inode_setattr(struct dentry *dentry, struct iattr *attr)
{
+ int ret;
+
if (unlikely(IS_PRIVATE(dentry->d_inode)))
return 0;
- return security_ops->inode_setattr(dentry, attr);
+ ret = security_ops->inode_setattr(dentry, attr);
+ if (ret)
+ return ret;
+ return evm_inode_setattr(dentry, attr);
}
EXPORT_SYMBOL_GPL(security_inode_setattr);
int security_inode_setxattr(struct dentry *dentry, const char *name,
const void *value, size_t size, int flags)
{
+ int ret;
+
if (unlikely(IS_PRIVATE(dentry->d_inode)))
return 0;
- return security_ops->inode_setxattr(dentry, name, value, size, flags);
+ ret = security_ops->inode_setxattr(dentry, name, value, size, flags);
+ if (ret)
+ return ret;
+ return evm_inode_setxattr(dentry, name, value, size);
}
void security_inode_post_setxattr(struct dentry *dentry, const char *name,
if (unlikely(IS_PRIVATE(dentry->d_inode)))
return;
security_ops->inode_post_setxattr(dentry, name, value, size, flags);
+ evm_inode_post_setxattr(dentry, name, value, size);
}
int security_inode_getxattr(struct dentry *dentry, const char *name)
int security_inode_removexattr(struct dentry *dentry, const char *name)
{
+ int ret;
+
if (unlikely(IS_PRIVATE(dentry->d_inode)))
return 0;
- return security_ops->inode_removexattr(dentry, name);
+ ret = security_ops->inode_removexattr(dentry, name);
+ if (ret)
+ return ret;
+ return evm_inode_removexattr(dentry, name);
}
int security_inode_need_killpriv(struct dentry *dentry)
git.openpandora.org / pandora-kernel.git / commitdiff