Fixed MTP to work with TWRP

security/integrity/Kconfig

@@ -0,0 +1,62 @@
+#
+config INTEGRITY
+	bool "Integrity subsystem"
+	depends on SECURITY
+	default y
+	help
+	  This option enables the integrity subsystem, which is comprised
+	  of a number of different components including the Integrity
+	  Measurement Architecture (IMA), Extended Verification Module
+	  (EVM), IMA-appraisal extension, digital signature verification
+	  extension and audit measurement log support.
+
+	  Each of these components can be enabled/disabled separately.
+	  Refer to the individual components for additional details.
+
+if INTEGRITY
+
+config INTEGRITY_SIGNATURE
+	boolean "Digital signature verification using multiple keyrings"
+	depends on KEYS
+	default n
+	select SIGNATURE
+	help
+	  This option enables digital signature verification support
+	  using multiple keyrings. It defines separate keyrings for each
+	  of the different use cases - evm, ima, and modules.
+	  Different keyrings improves search performance, but also allow
+	  to "lock" certain keyring to prevent adding new keys.
+	  This is useful for evm and module keyrings, when keys are
+	  usually only added from initramfs.
+
+config INTEGRITY_ASYMMETRIC_KEYS
+	boolean "Enable asymmetric keys support"
+	depends on INTEGRITY_SIGNATURE
+	default n
+        select ASYMMETRIC_KEY_TYPE
+        select ASYMMETRIC_PUBLIC_KEY_SUBTYPE
+        select PUBLIC_KEY_ALGO_RSA
+        select X509_CERTIFICATE_PARSER
+	help
+	  This option enables digital signature verification using
+	  asymmetric keys.
+
+config INTEGRITY_AUDIT
+	bool "Enables integrity auditing support "
+	depends on AUDIT
+	default y
+	help
+	  In addition to enabling integrity auditing support, this
+	  option adds a kernel parameter 'integrity_audit', which
+	  controls the level of integrity auditing messages.
+	  0 - basic integrity auditing messages (default)
+	  1 - additional integrity auditing messages
+
+	  Additional informational integrity auditing messages would
+	  be enabled by specifying 'integrity_audit=1' on the kernel
+	  command line.
+
+source security/integrity/ima/Kconfig
+source security/integrity/evm/Kconfig
+
+endif   # if INTEGRITY

security/integrity/Makefile

@@ -0,0 +1,15 @@
+#
+# Makefile for caching inode integrity data (iint)
+#
+
+obj-$(CONFIG_INTEGRITY) += integrity.o
+
+integrity-y := iint.o
+integrity-$(CONFIG_INTEGRITY_AUDIT) += integrity_audit.o
+integrity-$(CONFIG_INTEGRITY_SIGNATURE) += digsig.o
+integrity-$(CONFIG_INTEGRITY_ASYMMETRIC_KEYS) += digsig_asymmetric.o
+
+subdir-$(CONFIG_IMA)			+= ima
+obj-$(CONFIG_IMA)			+= ima/
+subdir-$(CONFIG_EVM)			+= evm
+obj-$(CONFIG_EVM)			+= evm/

security/integrity/digsig.c

@@ -0,0 +1,86 @@
+/*
+ * Copyright (C) 2011 Intel Corporation
+ *
+ * Author:
+ * Dmitry Kasatkin <dmitry.kasatkin@intel.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.
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/err.h>
+#include <linux/sched.h>
+#include <linux/rbtree.h>
+#include <linux/cred.h>
+#include <linux/key-type.h>
+#include <linux/digsig.h>
+
+#include "integrity.h"
+
+static struct key *keyring[INTEGRITY_KEYRING_MAX];
+
+static const char *keyring_name[INTEGRITY_KEYRING_MAX] = {
+	"_evm",
+	"_module",
+#ifndef CONFIG_IMA_TRUSTED_KEYRING
+	"_ima",
+#else
+	".ima",
+#endif
+};
+
+int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen,
+			    const char *digest, int digestlen)
+{
+	if (id >= INTEGRITY_KEYRING_MAX)
+		return -EINVAL;
+
+	if (!keyring[id]) {
+		keyring[id] =
+			request_key(&key_type_keyring, keyring_name[id], NULL);
+		if (IS_ERR(keyring[id])) {
+			int err = PTR_ERR(keyring[id]);
+			pr_err("no %s keyring: %d\n", keyring_name[id], err);
+			keyring[id] = NULL;
+			return err;
+		}
+	}
+
+	switch (sig[1]) {
+	case 1:
+		/* v1 API expect signature without xattr type */
+		return digsig_verify(keyring[id], sig + 1, siglen - 1,
+				     digest, digestlen);
+	case 2:
+		return asymmetric_verify(keyring[id], sig, siglen,
+					 digest, digestlen);
+	}
+
+	return -EOPNOTSUPP;
+}
+
+int integrity_init_keyring(const unsigned int id)
+{
+	const struct cred *cred = current_cred();
+	int err = 0;
+
+	keyring[id] = keyring_alloc(keyring_name[id], KUIDT_INIT(0),
+				    KGIDT_INIT(0), cred,
+				    ((KEY_POS_ALL & ~KEY_POS_SETATTR) |
+				     KEY_USR_VIEW | KEY_USR_READ |
+				     KEY_USR_WRITE | KEY_USR_SEARCH),
+				    KEY_ALLOC_NOT_IN_QUOTA, NULL);
+	if (!IS_ERR(keyring[id]))
+		set_bit(KEY_FLAG_TRUSTED_ONLY, &keyring[id]->flags);
+	else {
+		err = PTR_ERR(keyring[id]);
+		pr_info("Can't allocate %s keyring (%d)\n",
+			keyring_name[id], err);
+		keyring[id] = NULL;
+	}
+	return err;
+}

security/integrity/digsig_asymmetric.c

@@ -0,0 +1,105 @@
+/*
+ * Copyright (C) 2013 Intel Corporation
+ *
+ * Author:
+ * Dmitry Kasatkin <dmitry.kasatkin@intel.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.
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/err.h>
+#include <linux/ratelimit.h>
+#include <linux/key-type.h>
+#include <crypto/public_key.h>
+#include <keys/asymmetric-type.h>
+
+#include "integrity.h"
+
+/*
+ * Request an asymmetric key.
+ */
+static struct key *request_asymmetric_key(struct key *keyring, uint32_t keyid)
+{
+	struct key *key;
+	char name[12];
+
+	sprintf(name, "id:%08x", keyid);
+
+	pr_debug("key search: \"%s\"\n", name);
+
+	if (keyring) {
+		/* search in specific keyring */
+		key_ref_t kref;
+		kref = keyring_search(make_key_ref(keyring, 1),
+				      &key_type_asymmetric, name);
+		if (IS_ERR(kref))
+			key = ERR_CAST(kref);
+		else
+			key = key_ref_to_ptr(kref);
+	} else {
+		key = request_key(&key_type_asymmetric, name, NULL);
+	}
+
+	if (IS_ERR(key)) {
+		pr_err_ratelimited("Request for unknown key '%s' err %ld\n",
+				   name, PTR_ERR(key));
+		switch (PTR_ERR(key)) {
+			/* Hide some search errors */
+		case -EACCES:
+		case -ENOTDIR:
+		case -EAGAIN:
+			return ERR_PTR(-ENOKEY);
+		default:
+			return key;
+		}
+	}
+
+	pr_debug("%s() = 0 [%x]\n", __func__, key_serial(key));
+
+	return key;
+}
+
+int asymmetric_verify(struct key *keyring, const char *sig,
+		      int siglen, const char *data, int datalen)
+{
+	struct public_key_signature pks;
+	struct signature_v2_hdr *hdr = (struct signature_v2_hdr *)sig;
+	struct key *key;
+	int ret = -ENOMEM;
+
+	if (siglen <= sizeof(*hdr))
+		return -EBADMSG;
+
+	siglen -= sizeof(*hdr);
+
+	if (siglen != __be16_to_cpu(hdr->sig_size))
+		return -EBADMSG;
+
+	if (hdr->hash_algo >= PKEY_HASH__LAST)
+		return -ENOPKG;
+
+	key = request_asymmetric_key(keyring, __be32_to_cpu(hdr->keyid));
+	if (IS_ERR(key))
+		return PTR_ERR(key);
+
+	memset(&pks, 0, sizeof(pks));
+
+	pks.pkey_hash_algo = hdr->hash_algo;
+	pks.digest = (u8 *)data;
+	pks.digest_size = datalen;
+	pks.nr_mpi = 1;
+	pks.rsa.s = mpi_read_raw_data(hdr->sig, siglen);
+
+	if (pks.rsa.s)
+		ret = verify_signature(key, &pks);
+
+	mpi_free(pks.rsa.s);
+	key_put(key);
+	pr_debug("%s() = %d\n", __func__, ret);
+	return ret;
+}

security/integrity/evm/Kconfig

@@ -0,0 +1,44 @@
+config EVM
+	boolean "EVM support"
+	select KEYS
+	select ENCRYPTED_KEYS
+	select CRYPTO_HMAC
+	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.
+
+config EVM_ATTR_FSUUID
+	bool "FSUUID (version 2)"
+	default y
+	depends on EVM
+	help
+	  Include filesystem UUID for HMAC calculation.
+
+	  Default value is 'selected', which is former version 2.
+	  if 'not selected', it is former version 1
+
+	  WARNING: changing the HMAC calculation method or adding
+	  additional info to the calculation, requires existing EVM
+	  labeled file systems to be relabeled.
+
+config EVM_EXTRA_SMACK_XATTRS
+	bool "Additional SMACK xattrs"
+	depends on EVM && SECURITY_SMACK
+	default n
+	help
+	  Include additional SMACK xattrs for HMAC calculation.
+
+	  In addition to the original security xattrs (eg. security.selinux,
+	  security.SMACK64, security.capability, and security.ima) included
+	  in the HMAC calculation, enabling this option includes newly defined
+	  Smack xattrs: security.SMACK64EXEC, security.SMACK64TRANSMUTE and
+	  security.SMACK64MMAP.
+
+	  WARNING: changing the HMAC calculation method or adding
+	  additional info to the calculation, requires existing EVM
+	  labeled file systems to be relabeled.
+

security/integrity/evm/Makefile

@@ -0,0 +1,7 @@
+#
+# Makefile for building the Extended Verification Module(EVM)
+#
+obj-$(CONFIG_EVM) += evm.o
+
+evm-y := evm_main.o evm_crypto.o evm_secfs.o
+evm-$(CONFIG_FS_POSIX_ACL) += evm_posix_acl.o

security/integrity/evm/evm.h

@@ -0,0 +1,53 @@
+/*
+ * 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
+ *
+ */
+
+#ifndef __INTEGRITY_EVM_H
+#define __INTEGRITY_EVM_H
+
+#include <linux/xattr.h>
+#include <linux/security.h>
+
+#include "../integrity.h"
+
+extern int evm_initialized;
+extern char *evm_hmac;
+extern char *evm_hash;
+
+#define EVM_ATTR_FSUUID		0x0001
+
+extern int evm_hmac_attrs;
+
+extern struct crypto_shash *hmac_tfm;
+extern struct crypto_shash *hash_tfm;
+
+/* List of EVM protected security xattrs */
+extern char *evm_config_xattrnames[];
+
+int evm_init_key(void);
+int evm_update_evmxattr(struct dentry *dentry,
+			const char *req_xattr_name,
+			const char *req_xattr_value,
+			size_t req_xattr_value_len);
+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);
+int evm_calc_hash(struct dentry *dentry, const char *req_xattr_name,
+		  const char *req_xattr_value,
+		  size_t req_xattr_value_len, char *digest);
+int evm_init_hmac(struct inode *inode, const struct xattr *xattr,
+		  char *hmac_val);
+int evm_init_secfs(void);
+
+#endif

security/integrity/evm/evm_crypto.c

@@ -0,0 +1,262 @@
+/*
+ * 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
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#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;
+struct crypto_shash *hash_tfm;
+
+static DEFINE_MUTEX(mutex);
+
+static struct shash_desc *init_desc(char type)
+{
+	long rc;
+	char *algo;
+	struct crypto_shash **tfm;
+	struct shash_desc *desc;
+
+	if (type == EVM_XATTR_HMAC) {
+		tfm = &hmac_tfm;
+		algo = evm_hmac;
+	} else {
+		tfm = &hash_tfm;
+		algo = evm_hash;
+	}
+
+	if (*tfm == NULL) {
+		mutex_lock(&mutex);
+		if (*tfm)
+			goto out;
+		*tfm = crypto_alloc_shash(algo, 0, CRYPTO_ALG_ASYNC);
+		if (IS_ERR(*tfm)) {
+			rc = PTR_ERR(*tfm);
+			pr_err("Can not allocate %s (reason: %ld)\n", algo, rc);
+			*tfm = NULL;
+			mutex_unlock(&mutex);
+			return ERR_PTR(rc);
+		}
+		if (type == EVM_XATTR_HMAC) {
+			rc = crypto_shash_setkey(*tfm, evmkey, evmkey_len);
+			if (rc) {
+				crypto_free_shash(*tfm);
+				*tfm = NULL;
+				mutex_unlock(&mutex);
+				return ERR_PTR(rc);
+			}
+		}
+out:
+		mutex_unlock(&mutex);
+	}
+
+	desc = kmalloc(sizeof(*desc) + crypto_shash_descsize(*tfm),
+			GFP_KERNEL);
+	if (!desc)
+		return ERR_PTR(-ENOMEM);
+
+	desc->tfm = *tfm;
+	desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP;
+
+	rc = crypto_shash_init(desc);
+	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 = from_kuid(&init_user_ns, inode->i_uid);
+	hmac_misc.gid = from_kgid(&init_user_ns, inode->i_gid);
+	hmac_misc.mode = inode->i_mode;
+	crypto_shash_update(desc, (const u8 *)&hmac_misc, sizeof(hmac_misc));
+	if (evm_hmac_attrs & EVM_ATTR_FSUUID)
+		crypto_shash_update(desc, inode->i_sb->s_uuid,
+				    sizeof(inode->i_sb->s_uuid));
+	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.
+ */
+static int evm_calc_hmac_or_hash(struct dentry *dentry,
+				const char *req_xattr_name,
+				const char *req_xattr_value,
+				size_t req_xattr_value_len,
+				char type, 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->getxattr)
+		return -EOPNOTSUPP;
+	desc = init_desc(type);
+	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;
+}
+
+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)
+{
+	return evm_calc_hmac_or_hash(dentry, req_xattr_name, req_xattr_value,
+				req_xattr_value_len, EVM_XATTR_HMAC, digest);
+}
+
+int evm_calc_hash(struct dentry *dentry, const char *req_xattr_name,
+		  const char *req_xattr_value, size_t req_xattr_value_len,
+		  char *digest)
+{
+	return evm_calc_hmac_or_hash(dentry, req_xattr_name, req_xattr_value,
+				req_xattr_value_len, IMA_XATTR_DIGEST, digest);
+}
+
+/*
+ * 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 && inode->i_op->removexattr) {
+		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(EVM_XATTR_HMAC);
+	if (IS_ERR(desc)) {
+		pr_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;
+}

security/integrity/evm/evm_main.c

@@ -0,0 +1,494 @@
+/*
+ * 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
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/crypto.h>
+#include <linux/audit.h>
+#include <linux/xattr.h>
+#include <linux/integrity.h>
+#include <linux/evm.h>
+#include <crypto/hash.h>
+#include <crypto/algapi.h>
+#include "evm.h"
+
+int evm_initialized;
+
+static char *integrity_status_msg[] = {
+	"pass", "fail", "no_label", "no_xattrs", "unknown"
+};
+char *evm_hmac = "hmac(sha1)";
+char *evm_hash = "sha1";
+int evm_hmac_attrs;
+
+char *evm_config_xattrnames[] = {
+#ifdef CONFIG_SECURITY_SELINUX
+	XATTR_NAME_SELINUX,
+#endif
+#ifdef CONFIG_SECURITY_SMACK
+	XATTR_NAME_SMACK,
+#ifdef CONFIG_EVM_EXTRA_SMACK_XATTRS
+	XATTR_NAME_SMACKEXEC,
+	XATTR_NAME_SMACKTRANSMUTE,
+	XATTR_NAME_SMACKMMAP,
+#endif
+#endif
+#ifdef CONFIG_IMA_APPRAISE
+	XATTR_NAME_IMA,
+#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);
+
+static void __init evm_init_config(void)
+{
+#ifdef CONFIG_EVM_ATTR_FSUUID
+	evm_hmac_attrs |= EVM_ATTR_FSUUID;
+#endif
+	pr_info("HMAC attrs: 0x%x\n", evm_hmac_attrs);
+}
+
+static int evm_find_protected_xattrs(struct dentry *dentry)
+{
+	struct inode *inode = dentry->d_inode;
+	char **xattr;
+	int error;
+	int count = 0;
+
+	if (!inode->i_op->getxattr)
+		return -EOPNOTSUPP;
+
+	for (xattr = evm_config_xattrnames; *xattr != NULL; xattr++) {
+		error = inode->i_op->getxattr(dentry, *xattr, NULL, 0);
+		if (error < 0) {
+			if (error == -ENODATA)
+				continue;
+			return error;
+		}
+		count++;
+	}
+
+	return count;
+}
+
+/*
+ * 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 = NULL;
+	struct evm_ima_xattr_data calc;
+	enum integrity_status evm_status = INTEGRITY_PASS;
+	int rc, xattr_len;
+
+	if (iint && iint->evm_status == INTEGRITY_PASS)
+		return iint->evm_status;
+
+	/* if status is not PASS, try to check again - against -ENOMEM */
+
+	/* first need to know the sig type */
+	rc = vfs_getxattr_alloc(dentry, XATTR_NAME_EVM, (char **)&xattr_data, 0,
+				GFP_NOFS);
+	if (rc <= 0) {
+		evm_status = INTEGRITY_FAIL;
+		if (rc == -ENODATA) {
+			rc = evm_find_protected_xattrs(dentry);
+			if (rc > 0)
+				evm_status = INTEGRITY_NOLABEL;
+			else if (rc == 0)
+				evm_status = INTEGRITY_NOXATTRS; /* new file */
+		} else if (rc == -EOPNOTSUPP) {
+			evm_status = INTEGRITY_UNKNOWN;
+		}
+		goto out;
+	}
+
+	xattr_len = rc;
+
+	/* check value type */
+	switch (xattr_data->type) {
+	case EVM_XATTR_HMAC:
+		rc = evm_calc_hmac(dentry, xattr_name, xattr_value,
+				   xattr_value_len, calc.digest);
+		if (rc)
+			break;
+		rc = crypto_memneq(xattr_data->digest, calc.digest,
+			    sizeof(calc.digest));
+		if (rc)
+			rc = -EINVAL;
+		break;
+	case EVM_IMA_XATTR_DIGSIG:
+		rc = evm_calc_hash(dentry, xattr_name, xattr_value,
+				xattr_value_len, calc.digest);
+		if (rc)
+			break;
+		rc = integrity_digsig_verify(INTEGRITY_KEYRING_EVM,
+					(const char *)xattr_data, xattr_len,
+					calc.digest, sizeof(calc.digest));
+		if (!rc) {
+			/* we probably want to replace rsa with hmac here */
+			evm_update_evmxattr(dentry, xattr_name, xattr_value,
+				   xattr_value_len);
+		}
+		break;
+	default:
+		rc = -EINVAL;
+		break;
+	}
+
+	if (rc)
+		evm_status = (rc == -ENODATA) ?
+				INTEGRITY_NOXATTRS : INTEGRITY_FAIL;
+out:
+	if (iint)
+		iint->evm_status = evm_status;
+	kfree(xattr_data);
+	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_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_protect_xattr - protect the EVM extended attribute
+ *
+ * Prevent security.evm from being modified or removed without the
+ * necessary permissions or when the existing value is invalid.
+ *
+ * The posix xattr acls are 'system' prefixed, which normally would not
+ * affect security.evm.  An interesting side affect of writing posix xattr
+ * acls is their modifying of the i_mode, which is included in security.evm.
+ * For posix xattr acls only, permit security.evm, even if it currently
+ * doesn't exist, to be updated.
+ */
+static int evm_protect_xattr(struct dentry *dentry, const char *xattr_name,
+			     const void *xattr_value, size_t xattr_value_len)
+{
+	enum integrity_status evm_status;
+
+	if (strcmp(xattr_name, XATTR_NAME_EVM) == 0) {
+		if (!capable(CAP_SYS_ADMIN))
+			return -EPERM;
+	} else if (!evm_protected_xattr(xattr_name)) {
+		if (!posix_xattr_acl(xattr_name))
+			return 0;
+		evm_status = evm_verify_current_integrity(dentry);
+		if ((evm_status == INTEGRITY_PASS) ||
+		    (evm_status == INTEGRITY_NOXATTRS))
+			return 0;
+		goto out;
+	}
+	evm_status = evm_verify_current_integrity(dentry);
+	if (evm_status == INTEGRITY_NOXATTRS) {
+		struct integrity_iint_cache *iint;
+
+		iint = integrity_iint_find(dentry->d_inode);
+		if (iint && (iint->flags & IMA_NEW_FILE))
+			return 0;
+	}
+out:
+	if (evm_status != INTEGRITY_PASS)
+		integrity_audit_msg(AUDIT_INTEGRITY_METADATA, dentry->d_inode,
+				    dentry->d_name.name, "appraise_metadata",
+				    integrity_status_msg[evm_status],
+				    -EPERM, 0);
+	return evm_status == INTEGRITY_PASS ? 0 : -EPERM;
+}
+
+/**
+ * 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
+ *
+ * Before allowing the 'security.evm' protected xattr to be updated,
+ * verify the existing value is valid.  As only the kernel should have
+ * access to the EVM encrypted key needed to calculate the HMAC, prevent
+ * userspace from writing HMAC value.  Writing 'security.evm' requires
+ * requires CAP_SYS_ADMIN privileges.
+ */
+int evm_inode_setxattr(struct dentry *dentry, const char *xattr_name,
+		       const void *xattr_value, size_t xattr_value_len)
+{
+	const struct evm_ima_xattr_data *xattr_data = xattr_value;
+
+	if (strcmp(xattr_name, XATTR_NAME_EVM) == 0) {
+		if (!xattr_value_len)
+			return -EINVAL;
+		if (xattr_data->type != EVM_IMA_XATTR_DIGSIG)
+			return -EPERM;
+	}
+	return evm_protect_xattr(dentry, xattr_name, xattr_value,
+				 xattr_value_len);
+}
+
+/**
+ * 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)
+{
+	return evm_protect_xattr(dentry, xattr_name, NULL, 0);
+}
+
+/**
+ * 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)
+				 && !posix_xattr_acl(xattr_name)))
+		return;
+
+	evm_update_evmxattr(dentry, xattr_name, xattr_value, xattr_value_len);
+}
+
+/**
+ * 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);
+}
+
+/**
+ * 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);
+	if ((evm_status == INTEGRITY_PASS) ||
+	    (evm_status == INTEGRITY_NOXATTRS))
+		return 0;
+	integrity_audit_msg(AUDIT_INTEGRITY_METADATA, dentry->d_inode,
+			    dentry->d_name.name, "appraise_metadata",
+			    integrity_status_msg[evm_status], -EPERM, 0);
+	return -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);
+}
+
+/*
+ * 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 0;
+
+	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 = XATTR_EVM_SUFFIX;
+	return 0;
+out:
+	kfree(xattr_data);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(evm_inode_init_security);
+
+static int __init init_evm(void)
+{
+	int error;
+
+	evm_init_config();
+
+	error = evm_init_secfs();
+	if (error < 0) {
+		pr_info("Error registering secfs\n");
+		goto err;
+	}
+
+	return 0;
+err:
+	return error;
+}
+
+/*
+ * 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++)
+		pr_info("%s\n", *xattrname);
+	return 0;
+}
+
+pure_initcall(evm_display_config);
+late_initcall(init_evm);
+
+MODULE_DESCRIPTION("Extended Verification Module");
+MODULE_LICENSE("GPL");

security/integrity/evm/evm_posix_acl.c

@@ -0,0 +1,27 @@
+/*
+ * Copyright (C) 2011 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.
+ */
+
+#include <linux/module.h>
+#include <linux/xattr.h>
+#include <linux/evm.h>
+
+int posix_xattr_acl(const char *xattr)
+{
+	int xattr_len = strlen(xattr);
+
+	if ((strlen(XATTR_NAME_POSIX_ACL_ACCESS) == xattr_len)
+	     && (strncmp(XATTR_NAME_POSIX_ACL_ACCESS, xattr, xattr_len) == 0))
+		return 1;
+	if ((strlen(XATTR_NAME_POSIX_ACL_DEFAULT) == xattr_len)
+	     && (strncmp(XATTR_NAME_POSIX_ACL_DEFAULT, xattr, xattr_len) == 0))
+		return 1;
+	return 0;
+}

security/integrity/evm/evm_secfs.c

@@ -0,0 +1,104 @@
+/*
+ * 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
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#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("initialized\n");
+	} else
+		pr_err("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;
+}

security/integrity/iint.c

@@ -0,0 +1,172 @@
+/*
+ * 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_RWLOCK(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;
+
+	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;
+
+	read_lock(&integrity_iint_lock);
+	iint = __integrity_iint_find(inode);
+	read_unlock(&integrity_iint_lock);
+
+	return iint;
+}
+
+static void iint_free(struct integrity_iint_cache *iint)
+{
+	kfree(iint->ima_hash);
+	iint->ima_hash = NULL;
+	iint->version = 0;
+	iint->flags = 0UL;
+	iint->ima_file_status = INTEGRITY_UNKNOWN;
+	iint->ima_mmap_status = INTEGRITY_UNKNOWN;
+	iint->ima_bprm_status = INTEGRITY_UNKNOWN;
+	iint->ima_module_status = INTEGRITY_UNKNOWN;
+	iint->evm_status = INTEGRITY_UNKNOWN;
+	kmem_cache_free(iint_cache, iint);
+}
+
+/**
+ * integrity_inode_get - find or allocate an iint associated with an inode
+ * @inode: pointer to the inode
+ * @return: allocated iint
+ *
+ * Caller must lock i_mutex
+ */
+struct integrity_iint_cache *integrity_inode_get(struct inode *inode)
+{
+	struct rb_node **p;
+	struct rb_node *node, *parent = NULL;
+	struct integrity_iint_cache *iint, *test_iint;
+
+	iint = integrity_iint_find(inode);
+	if (iint)
+		return iint;
+
+	iint = kmem_cache_alloc(iint_cache, GFP_NOFS);
+	if (!iint)
+		return NULL;
+
+	write_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);
+		if (inode < test_iint->inode)
+			p = &(*p)->rb_left;
+		else
+			p = &(*p)->rb_right;
+	}
+
+	iint->inode = inode;
+	node = &iint->rb_node;
+	inode->i_flags |= S_IMA;
+	rb_link_node(node, parent, p);
+	rb_insert_color(node, &integrity_iint_tree);
+
+	write_unlock(&integrity_iint_lock);
+	return iint;
+}
+
+/**
+ * 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;
+
+	write_lock(&integrity_iint_lock);
+	iint = __integrity_iint_find(inode);
+	rb_erase(&iint->rb_node, &integrity_iint_tree);
+	write_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;
+	iint->ima_file_status = INTEGRITY_UNKNOWN;
+	iint->ima_mmap_status = INTEGRITY_UNKNOWN;
+	iint->ima_bprm_status = INTEGRITY_UNKNOWN;
+	iint->ima_module_status = INTEGRITY_UNKNOWN;
+	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);

security/integrity/ima/Kconfig

@@ -0,0 +1,133 @@
+# IBM Integrity Measurement Architecture
+#
+config IMA
+	bool "Integrity Measurement Architecture(IMA)"
+	select SECURITYFS
+	select CRYPTO
+	select CRYPTO_HMAC
+	select CRYPTO_MD5
+	select CRYPTO_SHA1
+	select CRYPTO_HASH_INFO
+	select TCG_TPM if HAS_IOMEM && !UML
+	select TCG_TIS if TCG_TPM && X86
+	select TCG_IBMVTPM if TCG_TPM && PPC64
+	help
+	  The Trusted Computing Group(TCG) runtime Integrity
+	  Measurement Architecture(IMA) maintains a list of hash
+	  values of executables and other sensitive system files,
+	  as they are read or executed. If an attacker manages
+	  to change the contents of an important system file
+	  being measured, we can tell.
+
+	  If your system has a TPM chip, then IMA also maintains
+	  an aggregate integrity value over this list inside the
+	  TPM hardware, so that the TPM can prove to a third party
+	  whether or not critical system files have been modified.
+	  Read <http://www.usenix.org/events/sec04/tech/sailer.html>
+	  to learn more about IMA.
+	  If unsure, say N.
+
+config IMA_MEASURE_PCR_IDX
+	int
+	depends on IMA
+	range 8 14
+	default 10
+	help
+	  IMA_MEASURE_PCR_IDX determines the TPM PCR register index
+	  that IMA uses to maintain the integrity aggregate of the
+	  measurement list.  If unsure, use the default 10.
+
+config IMA_LSM_RULES
+	bool
+	depends on IMA && AUDIT && (SECURITY_SELINUX || SECURITY_SMACK)
+	default y
+	help
+	  Disabling this option will disregard LSM based policy rules.
+
+choice
+	prompt "Default template"
+	default IMA_NG_TEMPLATE
+	depends on IMA
+	help
+	  Select the default IMA measurement template.
+
+	  The original 'ima' measurement list template contains a
+	  hash, defined as 20 bytes, and a null terminated pathname,
+	  limited to 255 characters.  The 'ima-ng' measurement list
+	  template permits both larger hash digests and longer
+	  pathnames.
+
+	config IMA_TEMPLATE
+		bool "ima"
+	config IMA_NG_TEMPLATE
+		bool "ima-ng (default)"
+	config IMA_SIG_TEMPLATE
+		bool "ima-sig"
+endchoice
+
+config IMA_DEFAULT_TEMPLATE
+	string
+	depends on IMA
+	default "ima" if IMA_TEMPLATE
+	default "ima-ng" if IMA_NG_TEMPLATE
+	default "ima-sig" if IMA_SIG_TEMPLATE
+
+choice
+	prompt "Default integrity hash algorithm"
+	default IMA_DEFAULT_HASH_SHA1
+	depends on IMA
+	help
+	   Select the default hash algorithm used for the measurement
+	   list, integrity appraisal and audit log.  The compiled default
+	   hash algorithm can be overwritten using the kernel command
+	   line 'ima_hash=' option.
+
+	config IMA_DEFAULT_HASH_SHA1
+		bool "SHA1 (default)"
+		depends on CRYPTO_SHA1
+
+	config IMA_DEFAULT_HASH_SHA256
+		bool "SHA256"
+		depends on CRYPTO_SHA256 && !IMA_TEMPLATE
+
+	config IMA_DEFAULT_HASH_SHA512
+		bool "SHA512"
+		depends on CRYPTO_SHA512 && !IMA_TEMPLATE
+
+	config IMA_DEFAULT_HASH_WP512
+		bool "WP512"
+		depends on CRYPTO_WP512 && !IMA_TEMPLATE
+endchoice
+
+config IMA_DEFAULT_HASH
+	string
+	depends on IMA
+	default "sha1" if IMA_DEFAULT_HASH_SHA1
+	default "sha256" if IMA_DEFAULT_HASH_SHA256
+	default "sha512" if IMA_DEFAULT_HASH_SHA512
+	default "wp512" if IMA_DEFAULT_HASH_WP512
+
+config IMA_APPRAISE
+	bool "Appraise integrity measurements"
+	depends on IMA
+	default n
+	help
+	  This option enables local measurement integrity appraisal.
+	  It requires the system to be labeled with a security extended
+	  attribute containing the file hash measurement.  To protect
+	  the security extended attributes from offline attack, enable
+	  and configure EVM.
+
+	  For more information on integrity appraisal refer to:
+	  <http://linux-ima.sourceforge.net>
+	  If unsure, say N.
+
+config IMA_TRUSTED_KEYRING
+	bool "Require all keys on the .ima keyring be signed"
+	depends on IMA_APPRAISE && SYSTEM_TRUSTED_KEYRING
+	depends on INTEGRITY_ASYMMETRIC_KEYS
+	select KEYS_DEBUG_PROC_KEYS
+	default y
+	help
+	   This option requires that all keys added to the .ima
+	   keyring be signed by a key on the system trusted keyring.

security/integrity/ima/Makefile

@@ -0,0 +1,10 @@
+#
+# Makefile for building Trusted Computing Group's(TCG) runtime Integrity
+# Measurement Architecture(IMA).
+#
+
+obj-$(CONFIG_IMA) += ima.o
+
+ima-y := ima_fs.o ima_queue.o ima_init.o ima_main.o ima_crypto.o ima_api.o \
+	 ima_policy.o ima_template.o ima_template_lib.o
+ima-$(CONFIG_IMA_APPRAISE) += ima_appraise.o

security/integrity/ima/ima.h

@@ -0,0 +1,259 @@
+/*
+ * Copyright (C) 2005,2006,2007,2008 IBM Corporation
+ *
+ * Authors:
+ * Reiner Sailer <sailer@watson.ibm.com>
+ * 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.h
+ *	internal Integrity Measurement Architecture (IMA) definitions
+ */
+
+#ifndef __LINUX_IMA_H
+#define __LINUX_IMA_H
+
+#include <linux/types.h>
+#include <linux/crypto.h>
+#include <linux/security.h>
+#include <linux/hash.h>
+#include <linux/tpm.h>
+#include <linux/audit.h>
+
+#include "../integrity.h"
+
+enum ima_show_type { IMA_SHOW_BINARY, IMA_SHOW_BINARY_NO_FIELD_LEN,
+		     IMA_SHOW_BINARY_OLD_STRING_FMT, IMA_SHOW_ASCII };
+enum tpm_pcrs { TPM_PCR0 = 0, TPM_PCR8 = 8 };
+
+/* digest size for IMA, fits SHA1 or MD5 */
+#define IMA_DIGEST_SIZE		SHA1_DIGEST_SIZE
+#define IMA_EVENT_NAME_LEN_MAX	255
+
+#define IMA_HASH_BITS 9
+#define IMA_MEASURE_HTABLE_SIZE (1 << IMA_HASH_BITS)
+
+#define IMA_TEMPLATE_FIELD_ID_MAX_LEN	16
+#define IMA_TEMPLATE_NUM_FIELDS_MAX	15
+
+#define IMA_TEMPLATE_IMA_NAME "ima"
+#define IMA_TEMPLATE_IMA_FMT "d|n"
+
+/* current content of the policy */
+extern int ima_policy_flag;
+
+/* set during initialization */
+extern int ima_initialized;
+extern int ima_used_chip;
+extern int ima_hash_algo;
+extern int ima_appraise;
+
+/* IMA template field data definition */
+struct ima_field_data {
+	u8 *data;
+	u32 len;
+};
+
+/* IMA template field definition */
+struct ima_template_field {
+	const char field_id[IMA_TEMPLATE_FIELD_ID_MAX_LEN];
+	int (*field_init) (struct integrity_iint_cache *iint, struct file *file,
+			   const unsigned char *filename,
+			   struct evm_ima_xattr_data *xattr_value,
+			   int xattr_len, struct ima_field_data *field_data);
+	void (*field_show) (struct seq_file *m, enum ima_show_type show,
+			    struct ima_field_data *field_data);
+};
+
+/* IMA template descriptor definition */
+struct ima_template_desc {
+	char *name;
+	char *fmt;
+	int num_fields;
+	struct ima_template_field **fields;
+};
+
+struct ima_template_entry {
+	u8 digest[TPM_DIGEST_SIZE];	/* sha1 or md5 measurement hash */
+	struct ima_template_desc *template_desc; /* template descriptor */
+	u32 template_data_len;
+	struct ima_field_data template_data[0];	/* template related data */
+};
+
+struct ima_queue_entry {
+	struct hlist_node hnext;	/* place in hash collision list */
+	struct list_head later;		/* place in ima_measurements list */
+	struct ima_template_entry *entry;
+};
+extern struct list_head ima_measurements;	/* list of all measurements */
+
+/* Internal IMA function definitions */
+int ima_init(void);
+int ima_fs_init(void);
+int ima_add_template_entry(struct ima_template_entry *entry, int violation,
+			   const char *op, struct inode *inode,
+			   const unsigned char *filename);
+int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash);
+int ima_calc_field_array_hash(struct ima_field_data *field_data,
+			      struct ima_template_desc *desc, int num_fields,
+			      struct ima_digest_data *hash);
+int __init ima_calc_boot_aggregate(struct ima_digest_data *hash);
+void ima_add_violation(struct file *file, const unsigned char *filename,
+		       const char *op, const char *cause);
+int ima_init_crypto(void);
+void ima_putc(struct seq_file *m, void *data, int datalen);
+void ima_print_digest(struct seq_file *m, u8 *digest, int size);
+struct ima_template_desc *ima_template_desc_current(void);
+int ima_init_template(void);
+
+/*
+ * used to protect h_table and sha_table
+ */
+extern spinlock_t ima_queue_lock;
+
+struct ima_h_table {
+	atomic_long_t len;	/* number of stored measurements in the list */
+	atomic_long_t violations;
+	struct hlist_head queue[IMA_MEASURE_HTABLE_SIZE];
+};
+extern struct ima_h_table ima_htable;
+
+static inline unsigned long ima_hash_key(u8 *digest)
+{
+	return hash_long(*digest, IMA_HASH_BITS);
+}
+
+/* LIM API function definitions */
+int ima_get_action(struct inode *inode, int mask, int function);
+int ima_must_measure(struct inode *inode, int mask, int function);
+int ima_collect_measurement(struct integrity_iint_cache *iint,
+			    struct file *file,
+			    struct evm_ima_xattr_data **xattr_value,
+			    int *xattr_len);
+void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file,
+			   const unsigned char *filename,
+			   struct evm_ima_xattr_data *xattr_value,
+			   int xattr_len);
+void ima_audit_measurement(struct integrity_iint_cache *iint,
+			   const unsigned char *filename);
+int ima_alloc_init_template(struct integrity_iint_cache *iint,
+			    struct file *file, const unsigned char *filename,
+			    struct evm_ima_xattr_data *xattr_value,
+			    int xattr_len, struct ima_template_entry **entry);
+int ima_store_template(struct ima_template_entry *entry, int violation,
+		       struct inode *inode, const unsigned char *filename);
+void ima_free_template_entry(struct ima_template_entry *entry);
+const char *ima_d_path(struct path *path, char **pathbuf);
+
+/* IMA policy related functions */
+enum ima_hooks { FILE_CHECK = 1, MMAP_CHECK, BPRM_CHECK, MODULE_CHECK, FIRMWARE_CHECK, POST_SETATTR };
+
+int ima_match_policy(struct inode *inode, enum ima_hooks func, int mask,
+		     int flags);
+void ima_init_policy(void);
+void ima_update_policy(void);
+void ima_update_policy_flag(void);
+ssize_t ima_parse_add_rule(char *);
+void ima_delete_rules(void);
+
+/* Appraise integrity measurements */
+#define IMA_APPRAISE_ENFORCE	0x01
+#define IMA_APPRAISE_FIX	0x02
+#define IMA_APPRAISE_LOG	0x04
+#define IMA_APPRAISE_MODULES	0x08
+#define IMA_APPRAISE_FIRMWARE	0x10
+
+#ifdef CONFIG_IMA_APPRAISE
+int ima_appraise_measurement(int func, struct integrity_iint_cache *iint,
+			     struct file *file, const unsigned char *filename,
+			     struct evm_ima_xattr_data *xattr_value,
+			     int xattr_len, int opened);
+int ima_must_appraise(struct inode *inode, int mask, enum ima_hooks func);
+void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file);
+enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint,
+					   int func);
+void ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, int xattr_len,
+		       struct ima_digest_data *hash);
+int ima_read_xattr(struct dentry *dentry,
+		   struct evm_ima_xattr_data **xattr_value);
+
+#else
+static inline int ima_appraise_measurement(int func,
+					   struct integrity_iint_cache *iint,
+					   struct file *file,
+					   const unsigned char *filename,
+					   struct evm_ima_xattr_data *xattr_value,
+					   int xattr_len, int opened)
+{
+	return INTEGRITY_UNKNOWN;
+}
+
+static inline int ima_must_appraise(struct inode *inode, int mask,
+				    enum ima_hooks func)
+{
+	return 0;
+}
+
+static inline void ima_update_xattr(struct integrity_iint_cache *iint,
+				    struct file *file)
+{
+}
+
+static inline enum integrity_status ima_get_cache_status(struct integrity_iint_cache
+							 *iint, int func)
+{
+	return INTEGRITY_UNKNOWN;
+}
+
+static inline void ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value,
+				     int xattr_len,
+				     struct ima_digest_data *hash)
+{
+}
+
+static inline int ima_read_xattr(struct dentry *dentry,
+				 struct evm_ima_xattr_data **xattr_value)
+{
+	return 0;
+}
+
+#endif
+
+/* LSM based policy rules require audit */
+#ifdef CONFIG_IMA_LSM_RULES
+
+#define security_filter_rule_init security_audit_rule_init
+#define security_filter_rule_match security_audit_rule_match
+
+#else
+
+static inline int security_filter_rule_init(u32 field, u32 op, char *rulestr,
+					    void **lsmrule)
+{
+	return -EINVAL;
+}
+
+static inline int security_filter_rule_match(u32 secid, u32 field, u32 op,
+					     void *lsmrule,
+					     struct audit_context *actx)
+{
+	return -EINVAL;
+}
+#endif /* CONFIG_IMA_LSM_RULES */
+
+#ifdef CONFIG_IMA_TRUSTED_KEYRING
+static inline int ima_init_keyring(const unsigned int id)
+{
+	return integrity_init_keyring(id);
+}
+#else
+static inline int ima_init_keyring(const unsigned int id)
+{
+	return 0;
+}
+#endif /* CONFIG_IMA_TRUSTED_KEYRING */
+#endif

security/integrity/ima/ima_api.c

@@ -0,0 +1,338 @@
+/*
+ * Copyright (C) 2008 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.
+ *
+ * File: ima_api.c
+ *	Implements must_appraise_or_measure, collect_measurement,
+ *	appraise_measurement, store_measurement and store_template.
+ */
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/file.h>
+#include <linux/fs.h>
+#include <linux/xattr.h>
+#include <linux/evm.h>
+#include <crypto/hash_info.h>
+#include "ima.h"
+
+/*
+ * ima_free_template_entry - free an existing template entry
+ */
+void ima_free_template_entry(struct ima_template_entry *entry)
+{
+	int i;
+
+	for (i = 0; i < entry->template_desc->num_fields; i++)
+		kfree(entry->template_data[i].data);
+
+	kfree(entry);
+}
+
+/*
+ * ima_alloc_init_template - create and initialize a new template entry
+ */
+int ima_alloc_init_template(struct integrity_iint_cache *iint,
+			    struct file *file, const unsigned char *filename,
+			    struct evm_ima_xattr_data *xattr_value,
+			    int xattr_len, struct ima_template_entry **entry)
+{
+	struct ima_template_desc *template_desc = ima_template_desc_current();
+	int i, result = 0;
+
+	*entry = kzalloc(sizeof(**entry) + template_desc->num_fields *
+			 sizeof(struct ima_field_data), GFP_NOFS);
+	if (!*entry)
+		return -ENOMEM;
+
+	(*entry)->template_desc = template_desc;
+	for (i = 0; i < template_desc->num_fields; i++) {
+		struct ima_template_field *field = template_desc->fields[i];
+		u32 len;
+
+		result = field->field_init(iint, file, filename,
+					   xattr_value, xattr_len,
+					   &((*entry)->template_data[i]));
+		if (result != 0)
+			goto out;
+
+		len = (*entry)->template_data[i].len;
+		(*entry)->template_data_len += sizeof(len);
+		(*entry)->template_data_len += len;
+	}
+	return 0;
+out:
+	ima_free_template_entry(*entry);
+	*entry = NULL;
+	return result;
+}
+
+/*
+ * ima_store_template - store ima template measurements
+ *
+ * Calculate the hash of a template entry, add the template entry
+ * to an ordered list of measurement entries maintained inside the kernel,
+ * and also update the aggregate integrity value (maintained inside the
+ * configured TPM PCR) over the hashes of the current list of measurement
+ * entries.
+ *
+ * Applications retrieve the current kernel-held measurement list through
+ * the securityfs entries in /sys/kernel/security/ima. The signed aggregate
+ * TPM PCR (called quote) can be retrieved using a TPM user space library
+ * and is used to validate the measurement list.
+ *
+ * Returns 0 on success, error code otherwise
+ */
+int ima_store_template(struct ima_template_entry *entry,
+		       int violation, struct inode *inode,
+		       const unsigned char *filename)
+{
+	static const char op[] = "add_template_measure";
+	static const char audit_cause[] = "hashing_error";
+	char *template_name = entry->template_desc->name;
+	int result;
+	struct {
+		struct ima_digest_data hdr;
+		char digest[TPM_DIGEST_SIZE];
+	} hash;
+
+	if (!violation) {
+		int num_fields = entry->template_desc->num_fields;
+
+		/* this function uses default algo */
+		hash.hdr.algo = HASH_ALGO_SHA1;
+		result = ima_calc_field_array_hash(&entry->template_data[0],
+						   entry->template_desc,
+						   num_fields, &hash.hdr);
+		if (result < 0) {
+			integrity_audit_msg(AUDIT_INTEGRITY_PCR, inode,
+					    template_name, op,
+					    audit_cause, result, 0);
+			return result;
+		}
+		memcpy(entry->digest, hash.hdr.digest, hash.hdr.length);
+	}
+	result = ima_add_template_entry(entry, violation, op, inode, filename);
+	return result;
+}
+
+/*
+ * ima_add_violation - add violation to measurement list.
+ *
+ * Violations are flagged in the measurement list with zero hash values.
+ * By extending the PCR with 0xFF's instead of with zeroes, the PCR
+ * value is invalidated.
+ */
+void ima_add_violation(struct file *file, const unsigned char *filename,
+		       const char *op, const char *cause)
+{
+	struct ima_template_entry *entry;
+	struct inode *inode = file_inode(file);
+	int violation = 1;
+	int result;
+
+	/* can overflow, only indicator */
+	atomic_long_inc(&ima_htable.violations);
+
+	result = ima_alloc_init_template(NULL, file, filename,
+					 NULL, 0, &entry);
+	if (result < 0) {
+		result = -ENOMEM;
+		goto err_out;
+	}
+	result = ima_store_template(entry, violation, inode, filename);
+	if (result < 0)
+		ima_free_template_entry(entry);
+err_out:
+	integrity_audit_msg(AUDIT_INTEGRITY_PCR, inode, filename,
+			    op, cause, result, 0);
+}
+
+/**
+ * ima_get_action - appraise & measure decision based on policy.
+ * @inode: pointer to inode to measure
+ * @mask: contains the permission mask (MAY_READ, MAY_WRITE, MAY_EXECUTE)
+ * @function: calling function (FILE_CHECK, BPRM_CHECK, MMAP_CHECK, MODULE_CHECK)
+ *
+ * The policy is defined in terms of keypairs:
+ *		subj=, obj=, type=, func=, mask=, fsmagic=
+ *	subj,obj, and type: are LSM specific.
+ *	func: FILE_CHECK | BPRM_CHECK | MMAP_CHECK | MODULE_CHECK
+ *	mask: contains the permission mask
+ *	fsmagic: hex value
+ *
+ * Returns IMA_MEASURE, IMA_APPRAISE mask.
+ *
+ */
+int ima_get_action(struct inode *inode, int mask, int function)
+{
+	int flags = IMA_MEASURE | IMA_AUDIT | IMA_APPRAISE;
+
+	if (!ima_appraise)
+		flags &= ~IMA_APPRAISE;
+
+	return ima_match_policy(inode, function, mask, flags);
+}
+
+/*
+ * ima_collect_measurement - collect file measurement
+ *
+ * Calculate the file hash, if it doesn't already exist,
+ * storing the measurement and i_version in the iint.
+ *
+ * Must be called with iint->mutex held.
+ *
+ * Return 0 on success, error code otherwise
+ */
+int ima_collect_measurement(struct integrity_iint_cache *iint,
+			    struct file *file,
+			    struct evm_ima_xattr_data **xattr_value,
+			    int *xattr_len)
+{
+	const char *audit_cause = "failed";
+	struct inode *inode = file_inode(file);
+	const char *filename = file->f_dentry->d_name.name;
+	int result = 0;
+	struct {
+		struct ima_digest_data hdr;
+		char digest[IMA_MAX_DIGEST_SIZE];
+	} hash;
+
+	if (xattr_value)
+		*xattr_len = ima_read_xattr(file->f_dentry, xattr_value);
+
+	if (!(iint->flags & IMA_COLLECTED)) {
+		u64 i_version = file_inode(file)->i_version;
+
+		if (file->f_flags & O_DIRECT) {
+			audit_cause = "failed(directio)";
+			result = -EACCES;
+			goto out;
+		}
+
+		/* use default hash algorithm */
+		hash.hdr.algo = ima_hash_algo;
+
+		if (xattr_value)
+			ima_get_hash_algo(*xattr_value, *xattr_len, &hash.hdr);
+
+		result = ima_calc_file_hash(file, &hash.hdr);
+		if (!result) {
+			int length = sizeof(hash.hdr) + hash.hdr.length;
+			void *tmpbuf = krealloc(iint->ima_hash, length,
+						GFP_NOFS);
+			if (tmpbuf) {
+				iint->ima_hash = tmpbuf;
+				memcpy(iint->ima_hash, &hash, length);
+				iint->version = i_version;
+				iint->flags |= IMA_COLLECTED;
+			} else
+				result = -ENOMEM;
+		}
+	}
+out:
+	if (result)
+		integrity_audit_msg(AUDIT_INTEGRITY_DATA, inode,
+				    filename, "collect_data", audit_cause,
+				    result, 0);
+	return result;
+}
+
+/*
+ * ima_store_measurement - store file measurement
+ *
+ * Create an "ima" template and then store the template by calling
+ * ima_store_template.
+ *
+ * We only get here if the inode has not already been measured,
+ * but the measurement could already exist:
+ *	- multiple copies of the same file on either the same or
+ *	  different filesystems.
+ *	- the inode was previously flushed as well as the iint info,
+ *	  containing the hashing info.
+ *
+ * Must be called with iint->mutex held.
+ */
+void ima_store_measurement(struct integrity_iint_cache *iint,
+			   struct file *file, const unsigned char *filename,
+			   struct evm_ima_xattr_data *xattr_value,
+			   int xattr_len)
+{
+	static const char op[] = "add_template_measure";
+	static const char audit_cause[] = "ENOMEM";
+	int result = -ENOMEM;
+	struct inode *inode = file_inode(file);
+	struct ima_template_entry *entry;
+	int violation = 0;
+
+	if (iint->flags & IMA_MEASURED)
+		return;
+
+	result = ima_alloc_init_template(iint, file, filename,
+					 xattr_value, xattr_len, &entry);
+	if (result < 0) {
+		integrity_audit_msg(AUDIT_INTEGRITY_PCR, inode, filename,
+				    op, audit_cause, result, 0);
+		return;
+	}
+
+	result = ima_store_template(entry, violation, inode, filename);
+	if (!result || result == -EEXIST)
+		iint->flags |= IMA_MEASURED;
+	if (result < 0)
+		ima_free_template_entry(entry);
+}
+
+void ima_audit_measurement(struct integrity_iint_cache *iint,
+			   const unsigned char *filename)
+{
+	struct audit_buffer *ab;
+	char hash[(iint->ima_hash->length * 2) + 1];
+	const char *algo_name = hash_algo_name[iint->ima_hash->algo];
+	char algo_hash[sizeof(hash) + strlen(algo_name) + 2];
+	int i;
+
+	if (iint->flags & IMA_AUDITED)
+		return;
+
+	for (i = 0; i < iint->ima_hash->length; i++)
+		hex_byte_pack(hash + (i * 2), iint->ima_hash->digest[i]);
+	hash[i * 2] = '\0';
+
+	ab = audit_log_start(current->audit_context, GFP_KERNEL,
+			     AUDIT_INTEGRITY_RULE);
+	if (!ab)
+		return;
+
+	audit_log_format(ab, "file=");
+	audit_log_untrustedstring(ab, filename);
+	audit_log_format(ab, " hash=");
+	snprintf(algo_hash, sizeof(algo_hash), "%s:%s", algo_name, hash);
+	audit_log_untrustedstring(ab, algo_hash);
+
+	audit_log_task_info(ab, current);
+	audit_log_end(ab);
+
+	iint->flags |= IMA_AUDITED;
+}
+
+const char *ima_d_path(struct path *path, char **pathbuf)
+{
+	char *pathname = NULL;
+
+	*pathbuf = kmalloc(PATH_MAX, GFP_KERNEL);
+	if (*pathbuf) {
+		pathname = d_absolute_path(path, *pathbuf, PATH_MAX);
+		if (IS_ERR(pathname)) {
+			kfree(*pathbuf);
+			*pathbuf = NULL;
+			pathname = NULL;
+		}
+	}
+	return pathname ?: (const char *)path->dentry->d_name.name;
+}

security/integrity/ima/ima_appraise.c

@@ -0,0 +1,400 @@
+/*
+ * Copyright (C) 2011 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.
+ */
+#include <linux/module.h>
+#include <linux/file.h>
+#include <linux/fs.h>
+#include <linux/xattr.h>
+#include <linux/magic.h>
+#include <linux/ima.h>
+#include <linux/evm.h>
+#include <crypto/hash_info.h>
+
+#include "ima.h"
+
+static int __init default_appraise_setup(char *str)
+{
+	if (strncmp(str, "off", 3) == 0)
+		ima_appraise = 0;
+	else if (strncmp(str, "log", 3) == 0)
+		ima_appraise = IMA_APPRAISE_LOG;
+	else if (strncmp(str, "fix", 3) == 0)
+		ima_appraise = IMA_APPRAISE_FIX;
+	return 1;
+}
+
+__setup("ima_appraise=", default_appraise_setup);
+
+/*
+ * ima_must_appraise - set appraise flag
+ *
+ * Return 1 to appraise
+ */
+int ima_must_appraise(struct inode *inode, int mask, enum ima_hooks func)
+{
+	if (!ima_appraise)
+		return 0;
+
+	return ima_match_policy(inode, func, mask, IMA_APPRAISE);
+}
+
+static int ima_fix_xattr(struct dentry *dentry,
+			 struct integrity_iint_cache *iint)
+{
+	int rc, offset;
+	u8 algo = iint->ima_hash->algo;
+
+	if (algo <= HASH_ALGO_SHA1) {
+		offset = 1;
+		iint->ima_hash->xattr.sha1.type = IMA_XATTR_DIGEST;
+	} else {
+		offset = 0;
+		iint->ima_hash->xattr.ng.type = IMA_XATTR_DIGEST_NG;
+		iint->ima_hash->xattr.ng.algo = algo;
+	}
+	rc = __vfs_setxattr_noperm(dentry, XATTR_NAME_IMA,
+				   &iint->ima_hash->xattr.data[offset],
+				   (sizeof(iint->ima_hash->xattr) - offset) +
+				   iint->ima_hash->length, 0);
+	return rc;
+}
+
+/* Return specific func appraised cached result */
+enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint,
+					   int func)
+{
+	switch (func) {
+	case MMAP_CHECK:
+		return iint->ima_mmap_status;
+	case BPRM_CHECK:
+		return iint->ima_bprm_status;
+	case MODULE_CHECK:
+		return iint->ima_module_status;
+	case FIRMWARE_CHECK:
+		return iint->ima_firmware_status;
+	case FILE_CHECK:
+	default:
+		return iint->ima_file_status;
+	}
+}
+
+static void ima_set_cache_status(struct integrity_iint_cache *iint,
+				 int func, enum integrity_status status)
+{
+	switch (func) {
+	case MMAP_CHECK:
+		iint->ima_mmap_status = status;
+		break;
+	case BPRM_CHECK:
+		iint->ima_bprm_status = status;
+		break;
+	case MODULE_CHECK:
+		iint->ima_module_status = status;
+		break;
+	case FIRMWARE_CHECK:
+		iint->ima_firmware_status = status;
+		break;
+	case FILE_CHECK:
+	default:
+		iint->ima_file_status = status;
+		break;
+	}
+}
+
+static void ima_cache_flags(struct integrity_iint_cache *iint, int func)
+{
+	switch (func) {
+	case MMAP_CHECK:
+		iint->flags |= (IMA_MMAP_APPRAISED | IMA_APPRAISED);
+		break;
+	case BPRM_CHECK:
+		iint->flags |= (IMA_BPRM_APPRAISED | IMA_APPRAISED);
+		break;
+	case MODULE_CHECK:
+		iint->flags |= (IMA_MODULE_APPRAISED | IMA_APPRAISED);
+		break;
+	case FIRMWARE_CHECK:
+		iint->flags |= (IMA_FIRMWARE_APPRAISED | IMA_APPRAISED);
+		break;
+	case FILE_CHECK:
+	default:
+		iint->flags |= (IMA_FILE_APPRAISED | IMA_APPRAISED);
+		break;
+	}
+}
+
+void ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, int xattr_len,
+		       struct ima_digest_data *hash)
+{
+	struct signature_v2_hdr *sig;
+
+	if (!xattr_value || xattr_len < 2)
+		return;
+
+	switch (xattr_value->type) {
+	case EVM_IMA_XATTR_DIGSIG:
+		sig = (typeof(sig))xattr_value;
+		if (sig->version != 2 || xattr_len <= sizeof(*sig))
+			return;
+		hash->algo = sig->hash_algo;
+		break;
+	case IMA_XATTR_DIGEST_NG:
+		hash->algo = xattr_value->digest[0];
+		break;
+	case IMA_XATTR_DIGEST:
+		/* this is for backward compatibility */
+		if (xattr_len == 21) {
+			unsigned int zero = 0;
+			if (!memcmp(&xattr_value->digest[16], &zero, 4))
+				hash->algo = HASH_ALGO_MD5;
+			else
+				hash->algo = HASH_ALGO_SHA1;
+		} else if (xattr_len == 17)
+			hash->algo = HASH_ALGO_MD5;
+		break;
+	}
+}
+
+int ima_read_xattr(struct dentry *dentry,
+		   struct evm_ima_xattr_data **xattr_value)
+{
+	struct inode *inode = dentry->d_inode;
+
+	if (!inode->i_op->getxattr)
+		return 0;
+
+	return vfs_getxattr_alloc(dentry, XATTR_NAME_IMA, (char **)xattr_value,
+				  0, GFP_NOFS);
+}
+
+/*
+ * ima_appraise_measurement - appraise file measurement
+ *
+ * Call evm_verifyxattr() to verify the integrity of 'security.ima'.
+ * Assuming success, compare the xattr hash with the collected measurement.
+ *
+ * Return 0 on success, error code otherwise
+ */
+int ima_appraise_measurement(int func, struct integrity_iint_cache *iint,
+			     struct file *file, const unsigned char *filename,
+			     struct evm_ima_xattr_data *xattr_value,
+			     int xattr_len, int opened)
+{
+	static const char op[] = "appraise_data";
+	char *cause = "unknown";
+	struct dentry *dentry = file->f_dentry;
+	struct inode *inode = dentry->d_inode;
+	enum integrity_status status = INTEGRITY_UNKNOWN;
+	int rc = xattr_len, hash_start = 0;
+
+	if (!inode->i_op->getxattr)
+		return INTEGRITY_UNKNOWN;
+
+	if (rc <= 0) {
+		if (rc && rc != -ENODATA)
+			goto out;
+
+		cause = "missing-hash";
+		status = INTEGRITY_NOLABEL;
+		if (opened & FILE_CREATED) {
+			iint->flags |= IMA_NEW_FILE;
+			status = INTEGRITY_PASS;
+		}
+		goto out;
+	}
+
+	status = evm_verifyxattr(dentry, XATTR_NAME_IMA, xattr_value, rc, iint);
+	if ((status != INTEGRITY_PASS) && (status != INTEGRITY_UNKNOWN)) {
+		if ((status == INTEGRITY_NOLABEL)
+		    || (status == INTEGRITY_NOXATTRS))
+			cause = "missing-HMAC";
+		else if (status == INTEGRITY_FAIL)
+			cause = "invalid-HMAC";
+		goto out;
+	}
+	switch (xattr_value->type) {
+	case IMA_XATTR_DIGEST_NG:
+		/* first byte contains algorithm id */
+		hash_start = 1;
+	case IMA_XATTR_DIGEST:
+		if (iint->flags & IMA_DIGSIG_REQUIRED) {
+			cause = "IMA-signature-required";
+			status = INTEGRITY_FAIL;
+			break;
+		}
+		if (xattr_len - sizeof(xattr_value->type) - hash_start >=
+				iint->ima_hash->length)
+			/* xattr length may be longer. md5 hash in previous
+			   version occupied 20 bytes in xattr, instead of 16
+			 */
+			rc = memcmp(&xattr_value->digest[hash_start],
+				    iint->ima_hash->digest,
+				    iint->ima_hash->length);
+		else
+			rc = -EINVAL;
+		if (rc) {
+			cause = "invalid-hash";
+			status = INTEGRITY_FAIL;
+			break;
+		}
+		status = INTEGRITY_PASS;
+		break;
+	case EVM_IMA_XATTR_DIGSIG:
+		iint->flags |= IMA_DIGSIG;
+		rc = integrity_digsig_verify(INTEGRITY_KEYRING_IMA,
+					     (const char *)xattr_value, rc,
+					     iint->ima_hash->digest,
+					     iint->ima_hash->length);
+		if (rc == -EOPNOTSUPP) {
+			status = INTEGRITY_UNKNOWN;
+		} else if (rc) {
+			cause = "invalid-signature";
+			status = INTEGRITY_FAIL;
+		} else {
+			status = INTEGRITY_PASS;
+		}
+		break;
+	default:
+		status = INTEGRITY_UNKNOWN;
+		cause = "unknown-ima-data";
+		break;
+	}
+
+out:
+	if (status != INTEGRITY_PASS) {
+		if ((ima_appraise & IMA_APPRAISE_FIX) &&
+		    (!xattr_value ||
+		     xattr_value->type != EVM_IMA_XATTR_DIGSIG)) {
+			if (!ima_fix_xattr(dentry, iint))
+				status = INTEGRITY_PASS;
+		}
+		integrity_audit_msg(AUDIT_INTEGRITY_DATA, inode, filename,
+				    op, cause, rc, 0);
+	} else {
+		ima_cache_flags(iint, func);
+	}
+	ima_set_cache_status(iint, func, status);
+	return status;
+}
+
+/*
+ * ima_update_xattr - update 'security.ima' hash value
+ */
+void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file)
+{
+	struct dentry *dentry = file->f_dentry;
+	int rc = 0;
+
+	/* do not collect and update hash for digital signatures */
+	if (iint->flags & IMA_DIGSIG)
+		return;
+
+	rc = ima_collect_measurement(iint, file, NULL, NULL);
+	if (rc < 0)
+		return;
+
+	ima_fix_xattr(dentry, iint);
+}
+
+/**
+ * ima_inode_post_setattr - reflect file metadata changes
+ * @dentry: pointer to the affected dentry
+ *
+ * Changes to a dentry's metadata might result in needing to appraise.
+ *
+ * This function is called from notify_change(), which expects the caller
+ * to lock the inode's i_mutex.
+ */
+void ima_inode_post_setattr(struct dentry *dentry)
+{
+	struct inode *inode = dentry->d_inode;
+	struct integrity_iint_cache *iint;
+	int must_appraise, rc;
+
+	if (!(ima_policy_flag & IMA_APPRAISE) || !S_ISREG(inode->i_mode)
+	    || !inode->i_op->removexattr)
+		return;
+
+	must_appraise = ima_must_appraise(inode, MAY_ACCESS, POST_SETATTR);
+	iint = integrity_iint_find(inode);
+	if (iint) {
+		iint->flags &= ~(IMA_APPRAISE | IMA_APPRAISED |
+				 IMA_APPRAISE_SUBMASK | IMA_APPRAISED_SUBMASK |
+				 IMA_ACTION_FLAGS);
+		if (must_appraise)
+			iint->flags |= IMA_APPRAISE;
+	}
+	if (!must_appraise)
+		rc = inode->i_op->removexattr(dentry, XATTR_NAME_IMA);
+	return;
+}
+
+/*
+ * ima_protect_xattr - protect 'security.ima'
+ *
+ * Ensure that not just anyone can modify or remove 'security.ima'.
+ */
+static int ima_protect_xattr(struct dentry *dentry, const char *xattr_name,
+			     const void *xattr_value, size_t xattr_value_len)
+{
+	if (strcmp(xattr_name, XATTR_NAME_IMA) == 0) {
+		if (!capable(CAP_SYS_ADMIN))
+			return -EPERM;
+		return 1;
+	}
+	return 0;
+}
+
+static void ima_reset_appraise_flags(struct inode *inode, int digsig)
+{
+	struct integrity_iint_cache *iint;
+
+	if (!(ima_policy_flag & IMA_APPRAISE) || !S_ISREG(inode->i_mode))
+		return;
+
+	iint = integrity_iint_find(inode);
+	if (!iint)
+		return;
+
+	iint->flags &= ~IMA_DONE_MASK;
+	if (digsig)
+		iint->flags |= IMA_DIGSIG;
+	return;
+}
+
+int ima_inode_setxattr(struct dentry *dentry, const char *xattr_name,
+		       const void *xattr_value, size_t xattr_value_len)
+{
+	const struct evm_ima_xattr_data *xvalue = xattr_value;
+	int result;
+
+	result = ima_protect_xattr(dentry, xattr_name, xattr_value,
+				   xattr_value_len);
+	if (result == 1) {
+		if (!xattr_value_len || (xvalue->type >= IMA_XATTR_LAST))
+			return -EINVAL;
+		ima_reset_appraise_flags(dentry->d_inode,
+			 (xvalue->type == EVM_IMA_XATTR_DIGSIG) ? 1 : 0);
+		result = 0;
+	}
+	return result;
+}
+
+int ima_inode_removexattr(struct dentry *dentry, const char *xattr_name)
+{
+	int result;
+
+	result = ima_protect_xattr(dentry, xattr_name, NULL, 0);
+	if (result == 1) {
+		ima_reset_appraise_flags(dentry->d_inode, 0);
+		result = 0;
+	}
+	return result;
+}

security/integrity/ima/ima_crypto.c

@@ -0,0 +1,603 @@
+/*
+ * Copyright (C) 2005,2006,2007,2008 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: ima_crypto.c
+ *	Calculates md5/sha1 file hash, template hash, boot-aggreate hash
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/moduleparam.h>
+#include <linux/ratelimit.h>
+#include <linux/file.h>
+#include <linux/crypto.h>
+#include <linux/scatterlist.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <crypto/hash.h>
+#include <crypto/hash_info.h>
+#include "ima.h"
+
+struct ahash_completion {
+	struct completion completion;
+	int err;
+};
+
+/* minimum file size for ahash use */
+static unsigned long ima_ahash_minsize;
+module_param_named(ahash_minsize, ima_ahash_minsize, ulong, 0644);
+MODULE_PARM_DESC(ahash_minsize, "Minimum file size for ahash use");
+
+/* default is 0 - 1 page. */
+static int ima_maxorder;
+static unsigned int ima_bufsize = PAGE_SIZE;
+
+static int param_set_bufsize(const char *val, const struct kernel_param *kp)
+{
+	unsigned long long size;
+	int order;
+
+	size = memparse(val, NULL);
+	order = get_order(size);
+	if (order >= MAX_ORDER)
+		return -EINVAL;
+	ima_maxorder = order;
+	ima_bufsize = PAGE_SIZE << order;
+	return 0;
+}
+
+static struct kernel_param_ops param_ops_bufsize = {
+	.set = param_set_bufsize,
+	.get = param_get_uint,
+};
+#define param_check_bufsize(name, p) __param_check(name, p, unsigned int)
+
+module_param_named(ahash_bufsize, ima_bufsize, bufsize, 0644);
+MODULE_PARM_DESC(ahash_bufsize, "Maximum ahash buffer size");
+
+static struct crypto_shash *ima_shash_tfm;
+static struct crypto_ahash *ima_ahash_tfm;
+
+/**
+ * ima_kernel_read - read file content
+ *
+ * This is a function for reading file content instead of kernel_read().
+ * It does not perform locking checks to ensure it cannot be blocked.
+ * It does not perform security checks because it is irrelevant for IMA.
+ *
+ */
+static int ima_kernel_read(struct file *file, loff_t offset,
+			   char *addr, unsigned long count)
+{
+	mm_segment_t old_fs;
+	char __user *buf = addr;
+	ssize_t ret = -EINVAL;
+
+	if (!(file->f_mode & FMODE_READ))
+		return -EBADF;
+
+	old_fs = get_fs();
+	set_fs(get_ds());
+	if (file->f_op->read)
+		ret = file->f_op->read(file, buf, count, &offset);
+	else if (file->f_op->aio_read)
+		ret = do_sync_read(file, buf, count, &offset);
+	else if (file->f_op->read_iter)
+		ret = new_sync_read(file, buf, count, &offset);
+	set_fs(old_fs);
+	return ret;
+}
+
+int __init ima_init_crypto(void)
+{
+	long rc;
+
+	ima_shash_tfm = crypto_alloc_shash(hash_algo_name[ima_hash_algo], 0, 0);
+	if (IS_ERR(ima_shash_tfm)) {
+		rc = PTR_ERR(ima_shash_tfm);
+		pr_err("Can not allocate %s (reason: %ld)\n",
+		       hash_algo_name[ima_hash_algo], rc);
+		return rc;
+	}
+	return 0;
+}
+
+static struct crypto_shash *ima_alloc_tfm(enum hash_algo algo)
+{
+	struct crypto_shash *tfm = ima_shash_tfm;
+	int rc;
+
+	if (algo < 0 || algo >= HASH_ALGO__LAST)
+		algo = ima_hash_algo;
+
+	if (algo != ima_hash_algo) {
+		tfm = crypto_alloc_shash(hash_algo_name[algo], 0, 0);
+		if (IS_ERR(tfm)) {
+			rc = PTR_ERR(tfm);
+			pr_err("Can not allocate %s (reason: %d)\n",
+			       hash_algo_name[algo], rc);
+		}
+	}
+	return tfm;
+}
+
+static void ima_free_tfm(struct crypto_shash *tfm)
+{
+	if (tfm != ima_shash_tfm)
+		crypto_free_shash(tfm);
+}
+
+/**
+ * ima_alloc_pages() - Allocate contiguous pages.
+ * @max_size:       Maximum amount of memory to allocate.
+ * @allocated_size: Returned size of actual allocation.
+ * @last_warn:      Should the min_size allocation warn or not.
+ *
+ * Tries to do opportunistic allocation for memory first trying to allocate
+ * max_size amount of memory and then splitting that until zero order is
+ * reached. Allocation is tried without generating allocation warnings unless
+ * last_warn is set. Last_warn set affects only last allocation of zero order.
+ *
+ * By default, ima_maxorder is 0 and it is equivalent to kmalloc(GFP_KERNEL)
+ *
+ * Return pointer to allocated memory, or NULL on failure.
+ */
+static void *ima_alloc_pages(loff_t max_size, size_t *allocated_size,
+			     int last_warn)
+{
+	void *ptr;
+	int order = ima_maxorder;
+	gfp_t gfp_mask = __GFP_WAIT | __GFP_NOWARN | __GFP_NORETRY;
+
+	if (order)
+		order = min(get_order(max_size), order);
+
+	for (; order; order--) {
+		ptr = (void *)__get_free_pages(gfp_mask, order);
+		if (ptr) {
+			*allocated_size = PAGE_SIZE << order;
+			return ptr;
+		}
+	}
+
+	/* order is zero - one page */
+
+	gfp_mask = GFP_KERNEL;
+
+	if (!last_warn)
+		gfp_mask |= __GFP_NOWARN;
+
+	ptr = (void *)__get_free_pages(gfp_mask, 0);
+	if (ptr) {
+		*allocated_size = PAGE_SIZE;
+		return ptr;
+	}
+
+	*allocated_size = 0;
+	return NULL;
+}
+
+/**
+ * ima_free_pages() - Free pages allocated by ima_alloc_pages().
+ * @ptr:  Pointer to allocated pages.
+ * @size: Size of allocated buffer.
+ */
+static void ima_free_pages(void *ptr, size_t size)
+{
+	if (!ptr)
+		return;
+	free_pages((unsigned long)ptr, get_order(size));
+}
+
+static struct crypto_ahash *ima_alloc_atfm(enum hash_algo algo)
+{
+	struct crypto_ahash *tfm = ima_ahash_tfm;
+	int rc;
+
+	if (algo < 0 || algo >= HASH_ALGO__LAST)
+		algo = ima_hash_algo;
+
+	if (algo != ima_hash_algo || !tfm) {
+		tfm = crypto_alloc_ahash(hash_algo_name[algo], 0, 0);
+		if (!IS_ERR(tfm)) {
+			if (algo == ima_hash_algo)
+				ima_ahash_tfm = tfm;
+		} else {
+			rc = PTR_ERR(tfm);
+			pr_err("Can not allocate %s (reason: %d)\n",
+			       hash_algo_name[algo], rc);
+		}
+	}
+	return tfm;
+}
+
+static void ima_free_atfm(struct crypto_ahash *tfm)
+{
+	if (tfm != ima_ahash_tfm)
+		crypto_free_ahash(tfm);
+}
+
+static void ahash_complete(struct crypto_async_request *req, int err)
+{
+	struct ahash_completion *res = req->data;
+
+	if (err == -EINPROGRESS)
+		return;
+	res->err = err;
+	complete(&res->completion);
+}
+
+static int ahash_wait(int err, struct ahash_completion *res)
+{
+	switch (err) {
+	case 0:
+		break;
+	case -EINPROGRESS:
+	case -EBUSY:
+		wait_for_completion(&res->completion);
+		reinit_completion(&res->completion);
+		err = res->err;
+		/* fall through */
+	default:
+		pr_crit_ratelimited("ahash calculation failed: err: %d\n", err);
+	}
+
+	return err;
+}
+
+static int ima_calc_file_hash_atfm(struct file *file,
+				   struct ima_digest_data *hash,
+				   struct crypto_ahash *tfm)
+{
+	loff_t i_size, offset;
+	char *rbuf[2] = { NULL, };
+	int rc, read = 0, rbuf_len, active = 0, ahash_rc = 0;
+	struct ahash_request *req;
+	struct scatterlist sg[1];
+	struct ahash_completion res;
+	size_t rbuf_size[2];
+
+	hash->length = crypto_ahash_digestsize(tfm);
+
+	req = ahash_request_alloc(tfm, GFP_KERNEL);
+	if (!req)
+		return -ENOMEM;
+
+	init_completion(&res.completion);
+	ahash_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG |
+				   CRYPTO_TFM_REQ_MAY_SLEEP,
+				   ahash_complete, &res);
+
+	rc = ahash_wait(crypto_ahash_init(req), &res);
+	if (rc)
+		goto out1;
+
+	i_size = i_size_read(file_inode(file));
+
+	if (i_size == 0)
+		goto out2;
+
+	/*
+	 * Try to allocate maximum size of memory.
+	 * Fail if even a single page cannot be allocated.
+	 */
+	rbuf[0] = ima_alloc_pages(i_size, &rbuf_size[0], 1);
+	if (!rbuf[0]) {
+		rc = -ENOMEM;
+		goto out1;
+	}
+
+	/* Only allocate one buffer if that is enough. */
+	if (i_size > rbuf_size[0]) {
+		/*
+		 * Try to allocate secondary buffer. If that fails fallback to
+		 * using single buffering. Use previous memory allocation size
+		 * as baseline for possible allocation size.
+		 */
+		rbuf[1] = ima_alloc_pages(i_size - rbuf_size[0],
+					  &rbuf_size[1], 0);
+	}
+
+	if (!(file->f_mode & FMODE_READ)) {
+		file->f_mode |= FMODE_READ;
+		read = 1;
+	}
+
+	for (offset = 0; offset < i_size; offset += rbuf_len) {
+		if (!rbuf[1] && offset) {
+			/* Not using two buffers, and it is not the first
+			 * read/request, wait for the completion of the
+			 * previous ahash_update() request.
+			 */
+			rc = ahash_wait(ahash_rc, &res);
+			if (rc)
+				goto out3;
+		}
+		/* read buffer */
+		rbuf_len = min_t(loff_t, i_size - offset, rbuf_size[active]);
+		rc = ima_kernel_read(file, offset, rbuf[active], rbuf_len);
+		if (rc != rbuf_len)
+			goto out3;
+
+		if (rbuf[1] && offset) {
+			/* Using two buffers, and it is not the first
+			 * read/request, wait for the completion of the
+			 * previous ahash_update() request.
+			 */
+			rc = ahash_wait(ahash_rc, &res);
+			if (rc)
+				goto out3;
+		}
+
+		sg_init_one(&sg[0], rbuf[active], rbuf_len);
+		ahash_request_set_crypt(req, sg, NULL, rbuf_len);
+
+		ahash_rc = crypto_ahash_update(req);
+
+		if (rbuf[1])
+			active = !active; /* swap buffers, if we use two */
+	}
+	/* wait for the last update request to complete */
+	rc = ahash_wait(ahash_rc, &res);
+out3:
+	if (read)
+		file->f_mode &= ~FMODE_READ;
+	ima_free_pages(rbuf[0], rbuf_size[0]);
+	ima_free_pages(rbuf[1], rbuf_size[1]);
+out2:
+	if (!rc) {
+		ahash_request_set_crypt(req, NULL, hash->digest, 0);
+		rc = ahash_wait(crypto_ahash_final(req), &res);
+	}
+out1:
+	ahash_request_free(req);
+	return rc;
+}
+
+static int ima_calc_file_ahash(struct file *file, struct ima_digest_data *hash)
+{
+	struct crypto_ahash *tfm;
+	int rc;
+
+	tfm = ima_alloc_atfm(hash->algo);
+	if (IS_ERR(tfm))
+		return PTR_ERR(tfm);
+
+	rc = ima_calc_file_hash_atfm(file, hash, tfm);
+
+	ima_free_atfm(tfm);
+
+	return rc;
+}
+
+static int ima_calc_file_hash_tfm(struct file *file,
+				  struct ima_digest_data *hash,
+				  struct crypto_shash *tfm)
+{
+	loff_t i_size, offset = 0;
+	char *rbuf;
+	int rc, read = 0;
+	SHASH_DESC_ON_STACK(shash, tfm);
+
+	shash->tfm = tfm;
+	shash->flags = 0;
+
+	hash->length = crypto_shash_digestsize(tfm);
+
+	rc = crypto_shash_init(shash);
+	if (rc != 0)
+		return rc;
+
+	i_size = i_size_read(file_inode(file));
+
+	if (i_size == 0)
+		goto out;
+
+	rbuf = kzalloc(PAGE_SIZE, GFP_KERNEL);
+	if (!rbuf)
+		return -ENOMEM;
+
+	if (!(file->f_mode & FMODE_READ)) {
+		file->f_mode |= FMODE_READ;
+		read = 1;
+	}
+
+	while (offset < i_size) {
+		int rbuf_len;
+
+		rbuf_len = ima_kernel_read(file, offset, rbuf, PAGE_SIZE);
+		if (rbuf_len < 0) {
+			rc = rbuf_len;
+			break;
+		}
+		if (rbuf_len == 0)
+			break;
+		offset += rbuf_len;
+
+		rc = crypto_shash_update(shash, rbuf, rbuf_len);
+		if (rc)
+			break;
+	}
+	if (read)
+		file->f_mode &= ~FMODE_READ;
+	kfree(rbuf);
+out:
+	if (!rc)
+		rc = crypto_shash_final(shash, hash->digest);
+	return rc;
+}
+
+static int ima_calc_file_shash(struct file *file, struct ima_digest_data *hash)
+{
+	struct crypto_shash *tfm;
+	int rc;
+
+	tfm = ima_alloc_tfm(hash->algo);
+	if (IS_ERR(tfm))
+		return PTR_ERR(tfm);
+
+	rc = ima_calc_file_hash_tfm(file, hash, tfm);
+
+	ima_free_tfm(tfm);
+
+	return rc;
+}
+
+/*
+ * ima_calc_file_hash - calculate file hash
+ *
+ * Asynchronous hash (ahash) allows using HW acceleration for calculating
+ * a hash. ahash performance varies for different data sizes on different
+ * crypto accelerators. shash performance might be better for smaller files.
+ * The 'ima.ahash_minsize' module parameter allows specifying the best
+ * minimum file size for using ahash on the system.
+ *
+ * If the ima.ahash_minsize parameter is not specified, this function uses
+ * shash for the hash calculation.  If ahash fails, it falls back to using
+ * shash.
+ */
+int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash)
+{
+	loff_t i_size;
+	int rc;
+
+	i_size = i_size_read(file_inode(file));
+
+	if (ima_ahash_minsize && i_size >= ima_ahash_minsize) {
+		rc = ima_calc_file_ahash(file, hash);
+		if (!rc)
+			return 0;
+	}
+
+	return ima_calc_file_shash(file, hash);
+}
+
+/*
+ * Calculate the hash of template data
+ */
+static int ima_calc_field_array_hash_tfm(struct ima_field_data *field_data,
+					 struct ima_template_desc *td,
+					 int num_fields,
+					 struct ima_digest_data *hash,
+					 struct crypto_shash *tfm)
+{
+	SHASH_DESC_ON_STACK(shash, tfm);
+	int rc, i;
+
+	shash->tfm = tfm;
+	shash->flags = 0;
+
+	hash->length = crypto_shash_digestsize(tfm);
+
+	rc = crypto_shash_init(shash);
+	if (rc != 0)
+		return rc;
+
+	for (i = 0; i < num_fields; i++) {
+		u8 buffer[IMA_EVENT_NAME_LEN_MAX + 1] = { 0 };
+		u8 *data_to_hash = field_data[i].data;
+		u32 datalen = field_data[i].len;
+
+		if (strcmp(td->name, IMA_TEMPLATE_IMA_NAME) != 0) {
+			rc = crypto_shash_update(shash,
+						(const u8 *) &field_data[i].len,
+						sizeof(field_data[i].len));
+			if (rc)
+				break;
+		} else if (strcmp(td->fields[i]->field_id, "n") == 0) {
+			memcpy(buffer, data_to_hash, datalen);
+			data_to_hash = buffer;
+			datalen = IMA_EVENT_NAME_LEN_MAX + 1;
+		}
+		rc = crypto_shash_update(shash, data_to_hash, datalen);
+		if (rc)
+			break;
+	}
+
+	if (!rc)
+		rc = crypto_shash_final(shash, hash->digest);
+
+	return rc;
+}
+
+int ima_calc_field_array_hash(struct ima_field_data *field_data,
+			      struct ima_template_desc *desc, int num_fields,
+			      struct ima_digest_data *hash)
+{
+	struct crypto_shash *tfm;
+	int rc;
+
+	tfm = ima_alloc_tfm(hash->algo);
+	if (IS_ERR(tfm))
+		return PTR_ERR(tfm);
+
+	rc = ima_calc_field_array_hash_tfm(field_data, desc, num_fields,
+					   hash, tfm);
+
+	ima_free_tfm(tfm);
+
+	return rc;
+}
+
+static void __init ima_pcrread(int idx, u8 *pcr)
+{
+	if (!ima_used_chip)
+		return;
+
+	if (tpm_pcr_read(TPM_ANY_NUM, idx, pcr) != 0)
+		pr_err("Error Communicating to TPM chip\n");
+}
+
+/*
+ * Calculate the boot aggregate hash
+ */
+static int __init ima_calc_boot_aggregate_tfm(char *digest,
+					      struct crypto_shash *tfm)
+{
+	u8 pcr_i[TPM_DIGEST_SIZE];
+	int rc, i;
+	SHASH_DESC_ON_STACK(shash, tfm);
+
+	shash->tfm = tfm;
+	shash->flags = 0;
+
+	rc = crypto_shash_init(shash);
+	if (rc != 0)
+		return rc;
+
+	/* cumulative sha1 over tpm registers 0-7 */
+	for (i = TPM_PCR0; i < TPM_PCR8; i++) {
+		ima_pcrread(i, pcr_i);
+		/* now accumulate with current aggregate */
+		rc = crypto_shash_update(shash, pcr_i, TPM_DIGEST_SIZE);
+	}
+	if (!rc)
+		crypto_shash_final(shash, digest);
+	return rc;
+}
+
+int __init ima_calc_boot_aggregate(struct ima_digest_data *hash)
+{
+	struct crypto_shash *tfm;
+	int rc;
+
+	tfm = ima_alloc_tfm(hash->algo);
+	if (IS_ERR(tfm))
+		return PTR_ERR(tfm);
+
+	hash->length = crypto_shash_digestsize(tfm);
+	rc = ima_calc_boot_aggregate_tfm(hash->digest, tfm);
+
+	ima_free_tfm(tfm);
+
+	return rc;
+}

security/integrity/ima/ima_fs.c

@@ -0,0 +1,382 @@
+/*
+ * Copyright (C) 2005,2006,2007,2008 IBM Corporation
+ *
+ * Authors:
+ * Kylene Hall <kjhall@us.ibm.com>
+ * Reiner Sailer <sailer@us.ibm.com>
+ * 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_fs.c
+ *	implemenents security file system for reporting
+ *	current measurement list and IMA statistics
+ */
+#include <linux/fcntl.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/seq_file.h>
+#include <linux/rculist.h>
+#include <linux/rcupdate.h>
+#include <linux/parser.h>
+
+#include "ima.h"
+
+static int valid_policy = 1;
+#define TMPBUFLEN 12
+static ssize_t ima_show_htable_value(char __user *buf, size_t count,
+				     loff_t *ppos, atomic_long_t *val)
+{
+	char tmpbuf[TMPBUFLEN];
+	ssize_t len;
+
+	len = scnprintf(tmpbuf, TMPBUFLEN, "%li\n", atomic_long_read(val));
+	return simple_read_from_buffer(buf, count, ppos, tmpbuf, len);
+}
+
+static ssize_t ima_show_htable_violations(struct file *filp,
+					  char __user *buf,
+					  size_t count, loff_t *ppos)
+{
+	return ima_show_htable_value(buf, count, ppos, &ima_htable.violations);
+}
+
+static const struct file_operations ima_htable_violations_ops = {
+	.read = ima_show_htable_violations,
+	.llseek = generic_file_llseek,
+};
+
+static ssize_t ima_show_measurements_count(struct file *filp,
+					   char __user *buf,
+					   size_t count, loff_t *ppos)
+{
+	return ima_show_htable_value(buf, count, ppos, &ima_htable.len);
+
+}
+
+static const struct file_operations ima_measurements_count_ops = {
+	.read = ima_show_measurements_count,
+	.llseek = generic_file_llseek,
+};
+
+/* returns pointer to hlist_node */
+static void *ima_measurements_start(struct seq_file *m, loff_t *pos)
+{
+	loff_t l = *pos;
+	struct ima_queue_entry *qe;
+
+	/* we need a lock since pos could point beyond last element */
+	rcu_read_lock();
+	list_for_each_entry_rcu(qe, &ima_measurements, later) {
+		if (!l--) {
+			rcu_read_unlock();
+			return qe;
+		}
+	}
+	rcu_read_unlock();
+	return NULL;
+}
+
+static void *ima_measurements_next(struct seq_file *m, void *v, loff_t *pos)
+{
+	struct ima_queue_entry *qe = v;
+
+	/* lock protects when reading beyond last element
+	 * against concurrent list-extension
+	 */
+	rcu_read_lock();
+	qe = list_entry_rcu(qe->later.next, struct ima_queue_entry, later);
+	rcu_read_unlock();
+	(*pos)++;
+
+	return (&qe->later == &ima_measurements) ? NULL : qe;
+}
+
+static void ima_measurements_stop(struct seq_file *m, void *v)
+{
+}
+
+void ima_putc(struct seq_file *m, void *data, int datalen)
+{
+	while (datalen--)
+		seq_putc(m, *(char *)data++);
+}
+
+/* print format:
+ *       32bit-le=pcr#
+ *       char[20]=template digest
+ *       32bit-le=template name size
+ *       char[n]=template name
+ *       [eventdata length]
+ *       eventdata[n]=template specific data
+ */
+static int ima_measurements_show(struct seq_file *m, void *v)
+{
+	/* the list never shrinks, so we don't need a lock here */
+	struct ima_queue_entry *qe = v;
+	struct ima_template_entry *e;
+	int namelen;
+	u32 pcr = CONFIG_IMA_MEASURE_PCR_IDX;
+	bool is_ima_template = false;
+	int i;
+
+	/* get entry */
+	e = qe->entry;
+	if (e == NULL)
+		return -1;
+
+	/*
+	 * 1st: PCRIndex
+	 * PCR used is always the same (config option) in
+	 * little-endian format
+	 */
+	ima_putc(m, &pcr, sizeof(pcr));
+
+	/* 2nd: template digest */
+	ima_putc(m, e->digest, TPM_DIGEST_SIZE);
+
+	/* 3rd: template name size */
+	namelen = strlen(e->template_desc->name);
+	ima_putc(m, &namelen, sizeof(namelen));
+
+	/* 4th:  template name */
+	ima_putc(m, e->template_desc->name, namelen);
+
+	/* 5th:  template length (except for 'ima' template) */
+	if (strcmp(e->template_desc->name, IMA_TEMPLATE_IMA_NAME) == 0)
+		is_ima_template = true;
+
+	if (!is_ima_template)
+		ima_putc(m, &e->template_data_len,
+			 sizeof(e->template_data_len));
+
+	/* 6th:  template specific data */
+	for (i = 0; i < e->template_desc->num_fields; i++) {
+		enum ima_show_type show = IMA_SHOW_BINARY;
+		struct ima_template_field *field = e->template_desc->fields[i];
+
+		if (is_ima_template && strcmp(field->field_id, "d") == 0)
+			show = IMA_SHOW_BINARY_NO_FIELD_LEN;
+		if (is_ima_template && strcmp(field->field_id, "n") == 0)
+			show = IMA_SHOW_BINARY_OLD_STRING_FMT;
+		field->field_show(m, show, &e->template_data[i]);
+	}
+	return 0;
+}
+
+static const struct seq_operations ima_measurments_seqops = {
+	.start = ima_measurements_start,
+	.next = ima_measurements_next,
+	.stop = ima_measurements_stop,
+	.show = ima_measurements_show
+};
+
+static int ima_measurements_open(struct inode *inode, struct file *file)
+{
+	return seq_open(file, &ima_measurments_seqops);
+}
+
+static const struct file_operations ima_measurements_ops = {
+	.open = ima_measurements_open,
+	.read = seq_read,
+	.llseek = seq_lseek,
+	.release = seq_release,
+};
+
+void ima_print_digest(struct seq_file *m, u8 *digest, int size)
+{
+	int i;
+
+	for (i = 0; i < size; i++)
+		seq_printf(m, "%02x", *(digest + i));
+}
+
+/* print in ascii */
+static int ima_ascii_measurements_show(struct seq_file *m, void *v)
+{
+	/* the list never shrinks, so we don't need a lock here */
+	struct ima_queue_entry *qe = v;
+	struct ima_template_entry *e;
+	int i;
+
+	/* get entry */
+	e = qe->entry;
+	if (e == NULL)
+		return -1;
+
+	/* 1st: PCR used (config option) */
+	seq_printf(m, "%2d ", CONFIG_IMA_MEASURE_PCR_IDX);
+
+	/* 2nd: SHA1 template hash */
+	ima_print_digest(m, e->digest, TPM_DIGEST_SIZE);
+
+	/* 3th:  template name */
+	seq_printf(m, " %s", e->template_desc->name);
+
+	/* 4th:  template specific data */
+	for (i = 0; i < e->template_desc->num_fields; i++) {
+		seq_puts(m, " ");
+		if (e->template_data[i].len == 0)
+			continue;
+
+		e->template_desc->fields[i]->field_show(m, IMA_SHOW_ASCII,
+							&e->template_data[i]);
+	}
+	seq_puts(m, "\n");
+	return 0;
+}
+
+static const struct seq_operations ima_ascii_measurements_seqops = {
+	.start = ima_measurements_start,
+	.next = ima_measurements_next,
+	.stop = ima_measurements_stop,
+	.show = ima_ascii_measurements_show
+};
+
+static int ima_ascii_measurements_open(struct inode *inode, struct file *file)
+{
+	return seq_open(file, &ima_ascii_measurements_seqops);
+}
+
+static const struct file_operations ima_ascii_measurements_ops = {
+	.open = ima_ascii_measurements_open,
+	.read = seq_read,
+	.llseek = seq_lseek,
+	.release = seq_release,
+};
+
+static ssize_t ima_write_policy(struct file *file, const char __user *buf,
+				size_t datalen, loff_t *ppos)
+{
+	char *data = NULL;
+	ssize_t result;
+
+	if (datalen >= PAGE_SIZE)
+		datalen = PAGE_SIZE - 1;
+
+	/* No partial writes. */
+	result = -EINVAL;
+	if (*ppos != 0)
+		goto out;
+
+	result = -ENOMEM;
+	data = kmalloc(datalen + 1, GFP_KERNEL);
+	if (!data)
+		goto out;
+
+	*(data + datalen) = '\0';
+
+	result = -EFAULT;
+	if (copy_from_user(data, buf, datalen))
+		goto out;
+
+	result = ima_parse_add_rule(data);
+out:
+	if (result < 0)
+		valid_policy = 0;
+	kfree(data);
+	return result;
+}
+
+static struct dentry *ima_dir;
+static struct dentry *binary_runtime_measurements;
+static struct dentry *ascii_runtime_measurements;
+static struct dentry *runtime_measurements_count;
+static struct dentry *violations;
+static struct dentry *ima_policy;
+
+static atomic_t policy_opencount = ATOMIC_INIT(1);
+/*
+ * ima_open_policy: sequentialize access to the policy file
+ */
+static int ima_open_policy(struct inode *inode, struct file *filp)
+{
+	/* No point in being allowed to open it if you aren't going to write */
+	if (!(filp->f_flags & O_WRONLY))
+		return -EACCES;
+	if (atomic_dec_and_test(&policy_opencount))
+		return 0;
+	return -EBUSY;
+}
+
+/*
+ * ima_release_policy - start using the new measure policy rules.
+ *
+ * Initially, ima_measure points to the default policy rules, now
+ * point to the new policy rules, and remove the securityfs policy file,
+ * assuming a valid policy.
+ */
+static int ima_release_policy(struct inode *inode, struct file *file)
+{
+	if (!valid_policy) {
+		ima_delete_rules();
+		valid_policy = 1;
+		atomic_set(&policy_opencount, 1);
+		return 0;
+	}
+	ima_update_policy();
+	securityfs_remove(ima_policy);
+	ima_policy = NULL;
+	return 0;
+}
+
+static const struct file_operations ima_measure_policy_ops = {
+	.open = ima_open_policy,
+	.write = ima_write_policy,
+	.release = ima_release_policy,
+	.llseek = generic_file_llseek,
+};
+
+int __init ima_fs_init(void)
+{
+	ima_dir = securityfs_create_dir("ima", NULL);
+	if (IS_ERR(ima_dir))
+		return -1;
+
+	binary_runtime_measurements =
+	    securityfs_create_file("binary_runtime_measurements",
+				   S_IRUSR | S_IRGRP, ima_dir, NULL,
+				   &ima_measurements_ops);
+	if (IS_ERR(binary_runtime_measurements))
+		goto out;
+
+	ascii_runtime_measurements =
+	    securityfs_create_file("ascii_runtime_measurements",
+				   S_IRUSR | S_IRGRP, ima_dir, NULL,
+				   &ima_ascii_measurements_ops);
+	if (IS_ERR(ascii_runtime_measurements))
+		goto out;
+
+	runtime_measurements_count =
+	    securityfs_create_file("runtime_measurements_count",
+				   S_IRUSR | S_IRGRP, ima_dir, NULL,
+				   &ima_measurements_count_ops);
+	if (IS_ERR(runtime_measurements_count))
+		goto out;
+
+	violations =
+	    securityfs_create_file("violations", S_IRUSR | S_IRGRP,
+				   ima_dir, NULL, &ima_htable_violations_ops);
+	if (IS_ERR(violations))
+		goto out;
+
+	ima_policy = securityfs_create_file("policy",
+					    S_IWUSR,
+					    ima_dir, NULL,
+					    &ima_measure_policy_ops);
+	if (IS_ERR(ima_policy))
+		goto out;
+
+	return 0;
+out:
+	securityfs_remove(violations);
+	securityfs_remove(runtime_measurements_count);
+	securityfs_remove(ascii_runtime_measurements);
+	securityfs_remove(binary_runtime_measurements);
+	securityfs_remove(ima_dir);
+	securityfs_remove(ima_policy);
+	return -1;
+}

security/integrity/ima/ima_init.c

@@ -0,0 +1,125 @@
+/*
+ * Copyright (C) 2005,2006,2007,2008 IBM Corporation
+ *
+ * Authors:
+ * Reiner Sailer      <sailer@watson.ibm.com>
+ * Leendert van Doorn <leendert@watson.ibm.com>
+ * 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_init.c
+ *             initialization and cleanup functions
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/scatterlist.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <crypto/hash_info.h>
+#include "ima.h"
+
+/* name for boot aggregate entry */
+static const char *boot_aggregate_name = "boot_aggregate";
+int ima_used_chip;
+
+/* Add the boot aggregate to the IMA measurement list and extend
+ * the PCR register.
+ *
+ * Calculate the boot aggregate, a SHA1 over tpm registers 0-7,
+ * assuming a TPM chip exists, and zeroes if the TPM chip does not
+ * exist.  Add the boot aggregate measurement to the measurement
+ * list and extend the PCR register.
+ *
+ * If a tpm chip does not exist, indicate the core root of trust is
+ * not hardware based by invalidating the aggregate PCR value.
+ * (The aggregate PCR value is invalidated by adding one value to
+ * the measurement list and extending the aggregate PCR value with
+ * a different value.) Violations add a zero entry to the measurement
+ * list and extend the aggregate PCR value with ff...ff's.
+ */
+static int __init ima_add_boot_aggregate(void)
+{
+	static const char op[] = "add_boot_aggregate";
+	const char *audit_cause = "ENOMEM";
+	struct ima_template_entry *entry;
+	struct integrity_iint_cache tmp_iint, *iint = &tmp_iint;
+	int result = -ENOMEM;
+	int violation = 0;
+	struct {
+		struct ima_digest_data hdr;
+		char digest[TPM_DIGEST_SIZE];
+	} hash;
+
+	memset(iint, 0, sizeof(*iint));
+	memset(&hash, 0, sizeof(hash));
+	iint->ima_hash = &hash.hdr;
+	iint->ima_hash->algo = HASH_ALGO_SHA1;
+	iint->ima_hash->length = SHA1_DIGEST_SIZE;
+
+	if (ima_used_chip) {
+		result = ima_calc_boot_aggregate(&hash.hdr);
+		if (result < 0) {
+			audit_cause = "hashing_error";
+			goto err_out;
+		}
+	}
+
+	result = ima_alloc_init_template(iint, NULL, boot_aggregate_name,
+					 NULL, 0, &entry);
+	if (result < 0) {
+		audit_cause = "alloc_entry";
+		goto err_out;
+	}
+
+	result = ima_store_template(entry, violation, NULL,
+				    boot_aggregate_name);
+	if (result < 0) {
+		ima_free_template_entry(entry);
+		audit_cause = "store_entry";
+		goto err_out;
+	}
+	return 0;
+err_out:
+	integrity_audit_msg(AUDIT_INTEGRITY_PCR, NULL, boot_aggregate_name, op,
+			    audit_cause, result, 0);
+	return result;
+}
+
+int __init ima_init(void)
+{
+	u8 pcr_i[TPM_DIGEST_SIZE];
+	int rc;
+
+	ima_used_chip = 0;
+	rc = tpm_pcr_read(TPM_ANY_NUM, 0, pcr_i);
+	if (rc == 0)
+		ima_used_chip = 1;
+
+	if (!ima_used_chip)
+		pr_info("No TPM chip found, activating TPM-bypass!\n");
+
+	rc = ima_init_keyring(INTEGRITY_KEYRING_IMA);
+	if (rc)
+		return rc;
+
+	rc = ima_init_crypto();
+	if (rc)
+		return rc;
+	rc = ima_init_template();
+	if (rc != 0)
+		return rc;
+
+	rc = ima_add_boot_aggregate();	/* boot aggregate must be first entry */
+	if (rc != 0)
+		return rc;
+
+	ima_init_policy();
+
+	return ima_fs_init();
+}

security/integrity/ima/ima_main.c

@@ -0,0 +1,360 @@
+/*
+ * Copyright (C) 2005,2006,2007,2008 IBM Corporation
+ *
+ * Authors:
+ * Reiner Sailer <sailer@watson.ibm.com>
+ * Serge Hallyn <serue@us.ibm.com>
+ * Kylene Hall <kylene@us.ibm.com>
+ * 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_main.c
+ *	implements the IMA hooks: ima_bprm_check, ima_file_mmap,
+ *	and ima_file_check.
+ */
+#include <linux/module.h>
+#include <linux/file.h>
+#include <linux/binfmts.h>
+#include <linux/mount.h>
+#include <linux/mman.h>
+#include <linux/slab.h>
+#include <linux/xattr.h>
+#include <linux/ima.h>
+#include <crypto/hash_info.h>
+
+#include "ima.h"
+
+int ima_initialized;
+
+#ifdef CONFIG_IMA_APPRAISE
+int ima_appraise = IMA_APPRAISE_ENFORCE;
+#else
+int ima_appraise;
+#endif
+
+int ima_hash_algo = HASH_ALGO_SHA1;
+static int hash_setup_done;
+
+static int __init hash_setup(char *str)
+{
+	struct ima_template_desc *template_desc = ima_template_desc_current();
+	int i;
+
+	if (hash_setup_done)
+		return 1;
+
+	if (strcmp(template_desc->name, IMA_TEMPLATE_IMA_NAME) == 0) {
+		if (strncmp(str, "sha1", 4) == 0)
+			ima_hash_algo = HASH_ALGO_SHA1;
+		else if (strncmp(str, "md5", 3) == 0)
+			ima_hash_algo = HASH_ALGO_MD5;
+		goto out;
+	}
+
+	for (i = 0; i < HASH_ALGO__LAST; i++) {
+		if (strcmp(str, hash_algo_name[i]) == 0) {
+			ima_hash_algo = i;
+			break;
+		}
+	}
+out:
+	hash_setup_done = 1;
+	return 1;
+}
+__setup("ima_hash=", hash_setup);
+
+/*
+ * ima_rdwr_violation_check
+ *
+ * Only invalidate the PCR for measured files:
+ *	- Opening a file for write when already open for read,
+ *	  results in a time of measure, time of use (ToMToU) error.
+ *	- Opening a file for read when already open for write,
+ *	  could result in a file measurement error.
+ *
+ */
+static void ima_rdwr_violation_check(struct file *file,
+				     struct integrity_iint_cache *iint,
+				     int must_measure,
+				     char **pathbuf,
+				     const char **pathname)
+{
+	struct inode *inode = file_inode(file);
+	fmode_t mode = file->f_mode;
+	bool send_tomtou = false, send_writers = false;
+
+	if (mode & FMODE_WRITE) {
+		if (atomic_read(&inode->i_readcount) && IS_IMA(inode)) {
+			if (!iint)
+				iint = integrity_iint_find(inode);
+			/* IMA_MEASURE is set from reader side */
+			if (iint && (iint->flags & IMA_MEASURE))
+				send_tomtou = true;
+		}
+	} else {
+		if ((atomic_read(&inode->i_writecount) > 0) && must_measure)
+			send_writers = true;
+	}
+
+	if (!send_tomtou && !send_writers)
+		return;
+
+	*pathname = ima_d_path(&file->f_path, pathbuf);
+
+	if (send_tomtou)
+		ima_add_violation(file, *pathname, "invalid_pcr", "ToMToU");
+	if (send_writers)
+		ima_add_violation(file, *pathname,
+				  "invalid_pcr", "open_writers");
+}
+
+static void ima_check_last_writer(struct integrity_iint_cache *iint,
+				  struct inode *inode, struct file *file)
+{
+	fmode_t mode = file->f_mode;
+
+	if (!(mode & FMODE_WRITE))
+		return;
+
+	mutex_lock(&inode->i_mutex);
+	if (atomic_read(&inode->i_writecount) == 1) {
+		if ((iint->version != inode->i_version) ||
+		    (iint->flags & IMA_NEW_FILE)) {
+			iint->flags &= ~(IMA_DONE_MASK | IMA_NEW_FILE);
+			if (iint->flags & IMA_APPRAISE)
+				ima_update_xattr(iint, file);
+		}
+	}
+	mutex_unlock(&inode->i_mutex);
+}
+
+/**
+ * ima_file_free - called on __fput()
+ * @file: pointer to file structure being freed
+ *
+ * Flag files that changed, based on i_version
+ */
+void ima_file_free(struct file *file)
+{
+	struct inode *inode = file_inode(file);
+	struct integrity_iint_cache *iint;
+
+	if (!iint_initialized || !S_ISREG(inode->i_mode))
+		return;
+
+	iint = integrity_iint_find(inode);
+	if (!iint)
+		return;
+
+	ima_check_last_writer(iint, inode, file);
+}
+
+static int process_measurement(struct file *file, int mask, int function,
+			       int opened)
+{
+	struct inode *inode = file_inode(file);
+	struct integrity_iint_cache *iint = NULL;
+	struct ima_template_desc *template_desc;
+	char *pathbuf = NULL;
+	const char *pathname = NULL;
+	int rc = -ENOMEM, action, must_appraise;
+	struct evm_ima_xattr_data *xattr_value = NULL, **xattr_ptr = NULL;
+	int xattr_len = 0;
+	bool violation_check;
+
+	if (!ima_policy_flag || !S_ISREG(inode->i_mode))
+		return 0;
+
+	/* Return an IMA_MEASURE, IMA_APPRAISE, IMA_AUDIT action
+	 * bitmask based on the appraise/audit/measurement policy.
+	 * Included is the appraise submask.
+	 */
+	action = ima_get_action(inode, mask, function);
+	violation_check = ((function == FILE_CHECK || function == MMAP_CHECK) &&
+			   (ima_policy_flag & IMA_MEASURE));
+	if (!action && !violation_check)
+		return 0;
+
+	must_appraise = action & IMA_APPRAISE;
+
+	/*  Is the appraise rule hook specific?  */
+	if (action & IMA_FILE_APPRAISE)
+		function = FILE_CHECK;
+
+	mutex_lock(&inode->i_mutex);
+
+	if (action) {
+		iint = integrity_inode_get(inode);
+		if (!iint)
+			goto out;
+	}
+
+	if (violation_check) {
+		ima_rdwr_violation_check(file, iint, action & IMA_MEASURE,
+					 &pathbuf, &pathname);
+		if (!action) {
+			rc = 0;
+			goto out_free;
+		}
+	}
+
+	/* Determine if already appraised/measured based on bitmask
+	 * (IMA_MEASURE, IMA_MEASURED, IMA_XXXX_APPRAISE, IMA_XXXX_APPRAISED,
+	 *  IMA_AUDIT, IMA_AUDITED)
+	 */
+	iint->flags |= action;
+	action &= IMA_DO_MASK;
+	action &= ~((iint->flags & IMA_DONE_MASK) >> 1);
+
+	/* Nothing to do, just return existing appraised status */
+	if (!action) {
+		if (must_appraise)
+			rc = ima_get_cache_status(iint, function);
+		goto out_digsig;
+	}
+
+	template_desc = ima_template_desc_current();
+	if ((action & IMA_APPRAISE_SUBMASK) ||
+		    strcmp(template_desc->name, IMA_TEMPLATE_IMA_NAME) != 0)
+		xattr_ptr = &xattr_value;
+
+	rc = ima_collect_measurement(iint, file, xattr_ptr, &xattr_len);
+	if (rc != 0) {
+		if (file->f_flags & O_DIRECT)
+			rc = (iint->flags & IMA_PERMIT_DIRECTIO) ? 0 : -EACCES;
+		goto out_digsig;
+	}
+
+	if (!pathname)	/* ima_rdwr_violation possibly pre-fetched */
+		pathname = ima_d_path(&file->f_path, &pathbuf);
+
+	if (action & IMA_MEASURE)
+		ima_store_measurement(iint, file, pathname,
+				      xattr_value, xattr_len);
+	if (action & IMA_APPRAISE_SUBMASK)
+		rc = ima_appraise_measurement(function, iint, file, pathname,
+					      xattr_value, xattr_len, opened);
+	if (action & IMA_AUDIT)
+		ima_audit_measurement(iint, pathname);
+
+out_digsig:
+	if ((mask & MAY_WRITE) && (iint->flags & IMA_DIGSIG))
+		rc = -EACCES;
+	kfree(xattr_value);
+out_free:
+	kfree(pathbuf);
+out:
+	mutex_unlock(&inode->i_mutex);
+	if ((rc && must_appraise) && (ima_appraise & IMA_APPRAISE_ENFORCE))
+		return -EACCES;
+	return 0;
+}
+
+/**
+ * ima_file_mmap - based on policy, collect/store measurement.
+ * @file: pointer to the file to be measured (May be NULL)
+ * @prot: contains the protection that will be applied by the kernel.
+ *
+ * Measure files being mmapped executable based on the ima_must_measure()
+ * policy decision.
+ *
+ * On success return 0.  On integrity appraisal error, assuming the file
+ * is in policy and IMA-appraisal is in enforcing mode, return -EACCES.
+ */
+int ima_file_mmap(struct file *file, unsigned long prot)
+{
+	if (file && (prot & PROT_EXEC))
+		return process_measurement(file, MAY_EXEC, MMAP_CHECK, 0);
+	return 0;
+}
+
+/**
+ * ima_bprm_check - based on policy, collect/store measurement.
+ * @bprm: contains the linux_binprm structure
+ *
+ * The OS protects against an executable file, already open for write,
+ * from being executed in deny_write_access() and an executable file,
+ * already open for execute, from being modified in get_write_access().
+ * So we can be certain that what we verify and measure here is actually
+ * what is being executed.
+ *
+ * On success return 0.  On integrity appraisal error, assuming the file
+ * is in policy and IMA-appraisal is in enforcing mode, return -EACCES.
+ */
+int ima_bprm_check(struct linux_binprm *bprm)
+{
+	return process_measurement(bprm->file, MAY_EXEC, BPRM_CHECK, 0);
+}
+
+/**
+ * ima_path_check - based on policy, collect/store measurement.
+ * @file: pointer to the file to be measured
+ * @mask: contains MAY_READ, MAY_WRITE or MAY_EXECUTE
+ *
+ * Measure files based on the ima_must_measure() policy decision.
+ *
+ * On success return 0.  On integrity appraisal error, assuming the file
+ * is in policy and IMA-appraisal is in enforcing mode, return -EACCES.
+ */
+int ima_file_check(struct file *file, int mask, int opened)
+{
+	return process_measurement(file,
+				   mask & (MAY_READ | MAY_WRITE | MAY_EXEC),
+				   FILE_CHECK, opened);
+}
+EXPORT_SYMBOL_GPL(ima_file_check);
+
+/**
+ * ima_module_check - based on policy, collect/store/appraise measurement.
+ * @file: pointer to the file to be measured/appraised
+ *
+ * Measure/appraise kernel modules based on policy.
+ *
+ * On success return 0.  On integrity appraisal error, assuming the file
+ * is in policy and IMA-appraisal is in enforcing mode, return -EACCES.
+ */
+int ima_module_check(struct file *file)
+{
+	if (!file) {
+#ifndef CONFIG_MODULE_SIG_FORCE
+		if ((ima_appraise & IMA_APPRAISE_MODULES) &&
+		    (ima_appraise & IMA_APPRAISE_ENFORCE))
+			return -EACCES;	/* INTEGRITY_UNKNOWN */
+#endif
+		return 0;	/* We rely on module signature checking */
+	}
+	return process_measurement(file, MAY_EXEC, MODULE_CHECK, 0);
+}
+
+int ima_fw_from_file(struct file *file, char *buf, size_t size)
+{
+	if (!file) {
+		if ((ima_appraise & IMA_APPRAISE_FIRMWARE) &&
+		    (ima_appraise & IMA_APPRAISE_ENFORCE))
+			return -EACCES;	/* INTEGRITY_UNKNOWN */
+		return 0;
+	}
+	return process_measurement(file, MAY_EXEC, FIRMWARE_CHECK, 0);
+}
+
+static int __init init_ima(void)
+{
+	int error;
+
+	hash_setup(CONFIG_IMA_DEFAULT_HASH);
+	error = ima_init();
+	if (!error) {
+		ima_initialized = 1;
+		ima_update_policy_flag();
+	}
+	return error;
+}
+
+late_initcall(init_ima);	/* Start IMA after the TPM is available */
+
+MODULE_DESCRIPTION("Integrity Measurement Architecture");
+MODULE_LICENSE("GPL");

security/integrity/ima/ima_policy.c

@@ -0,0 +1,745 @@
+/*
+ * Copyright (C) 2008 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.
+ *
+ * ima_policy.c
+ *	- initialize default measure policy rules
+ *
+ */
+#include <linux/module.h>
+#include <linux/list.h>
+#include <linux/security.h>
+#include <linux/magic.h>
+#include <linux/parser.h>
+#include <linux/slab.h>
+#include <linux/genhd.h>
+
+#include "ima.h"
+
+/* flags definitions */
+#define IMA_FUNC	0x0001
+#define IMA_MASK	0x0002
+#define IMA_FSMAGIC	0x0004
+#define IMA_UID		0x0008
+#define IMA_FOWNER	0x0010
+#define IMA_FSUUID	0x0020
+
+#define UNKNOWN		0
+#define MEASURE		0x0001	/* same as IMA_MEASURE */
+#define DONT_MEASURE	0x0002
+#define APPRAISE	0x0004	/* same as IMA_APPRAISE */
+#define DONT_APPRAISE	0x0008
+#define AUDIT		0x0040
+
+int ima_policy_flag;
+
+#define MAX_LSM_RULES 6
+enum lsm_rule_types { LSM_OBJ_USER, LSM_OBJ_ROLE, LSM_OBJ_TYPE,
+	LSM_SUBJ_USER, LSM_SUBJ_ROLE, LSM_SUBJ_TYPE
+};
+
+struct ima_rule_entry {
+	struct list_head list;
+	int action;
+	unsigned int flags;
+	enum ima_hooks func;
+	int mask;
+	unsigned long fsmagic;
+	u8 fsuuid[16];
+	kuid_t uid;
+	kuid_t fowner;
+	struct {
+		void *rule;	/* LSM file metadata specific */
+		void *args_p;	/* audit value */
+		int type;	/* audit type */
+	} lsm[MAX_LSM_RULES];
+};
+
+/*
+ * Without LSM specific knowledge, the default policy can only be
+ * written in terms of .action, .func, .mask, .fsmagic, .uid, and .fowner
+ */
+
+/*
+ * The minimum rule set to allow for full TCB coverage.  Measures all files
+ * opened or mmap for exec and everything read by root.  Dangerous because
+ * normal users can easily run the machine out of memory simply building
+ * and running executables.
+ */
+static struct ima_rule_entry default_rules[] = {
+	{.action = DONT_MEASURE, .fsmagic = PROC_SUPER_MAGIC, .flags = IMA_FSMAGIC},
+	{.action = DONT_MEASURE, .fsmagic = SYSFS_MAGIC, .flags = IMA_FSMAGIC},
+	{.action = DONT_MEASURE, .fsmagic = DEBUGFS_MAGIC, .flags = IMA_FSMAGIC},
+	{.action = DONT_MEASURE, .fsmagic = TMPFS_MAGIC, .flags = IMA_FSMAGIC},
+	{.action = DONT_MEASURE, .fsmagic = DEVPTS_SUPER_MAGIC, .flags = IMA_FSMAGIC},
+	{.action = DONT_MEASURE, .fsmagic = BINFMTFS_MAGIC, .flags = IMA_FSMAGIC},
+	{.action = DONT_MEASURE, .fsmagic = SECURITYFS_MAGIC, .flags = IMA_FSMAGIC},
+	{.action = DONT_MEASURE, .fsmagic = SELINUX_MAGIC, .flags = IMA_FSMAGIC},
+	{.action = MEASURE, .func = MMAP_CHECK, .mask = MAY_EXEC,
+	 .flags = IMA_FUNC | IMA_MASK},
+	{.action = MEASURE, .func = BPRM_CHECK, .mask = MAY_EXEC,
+	 .flags = IMA_FUNC | IMA_MASK},
+	{.action = MEASURE, .func = FILE_CHECK, .mask = MAY_READ, .uid = GLOBAL_ROOT_UID,
+	 .flags = IMA_FUNC | IMA_MASK | IMA_UID},
+	{.action = MEASURE, .func = MODULE_CHECK, .flags = IMA_FUNC},
+	{.action = MEASURE, .func = FIRMWARE_CHECK, .flags = IMA_FUNC},
+};
+
+static struct ima_rule_entry default_appraise_rules[] = {
+	{.action = DONT_APPRAISE, .fsmagic = PROC_SUPER_MAGIC, .flags = IMA_FSMAGIC},
+	{.action = DONT_APPRAISE, .fsmagic = SYSFS_MAGIC, .flags = IMA_FSMAGIC},
+	{.action = DONT_APPRAISE, .fsmagic = DEBUGFS_MAGIC, .flags = IMA_FSMAGIC},
+	{.action = DONT_APPRAISE, .fsmagic = TMPFS_MAGIC, .flags = IMA_FSMAGIC},
+	{.action = DONT_APPRAISE, .fsmagic = RAMFS_MAGIC, .flags = IMA_FSMAGIC},
+	{.action = DONT_APPRAISE, .fsmagic = DEVPTS_SUPER_MAGIC, .flags = IMA_FSMAGIC},
+	{.action = DONT_APPRAISE, .fsmagic = BINFMTFS_MAGIC, .flags = IMA_FSMAGIC},
+	{.action = DONT_APPRAISE, .fsmagic = SECURITYFS_MAGIC, .flags = IMA_FSMAGIC},
+	{.action = DONT_APPRAISE, .fsmagic = SELINUX_MAGIC, .flags = IMA_FSMAGIC},
+	{.action = DONT_APPRAISE, .fsmagic = CGROUP_SUPER_MAGIC, .flags = IMA_FSMAGIC},
+	{.action = APPRAISE, .fowner = GLOBAL_ROOT_UID, .flags = IMA_FOWNER},
+};
+
+static LIST_HEAD(ima_default_rules);
+static LIST_HEAD(ima_policy_rules);
+static struct list_head *ima_rules;
+
+static DEFINE_MUTEX(ima_rules_mutex);
+
+static bool ima_use_tcb __initdata;
+static int __init default_measure_policy_setup(char *str)
+{
+	ima_use_tcb = 1;
+	return 1;
+}
+__setup("ima_tcb", default_measure_policy_setup);
+
+static bool ima_use_appraise_tcb __initdata;
+static int __init default_appraise_policy_setup(char *str)
+{
+	ima_use_appraise_tcb = 1;
+	return 1;
+}
+__setup("ima_appraise_tcb", default_appraise_policy_setup);
+
+/*
+ * Although the IMA policy does not change, the LSM policy can be
+ * reloaded, leaving the IMA LSM based rules referring to the old,
+ * stale LSM policy.
+ *
+ * Update the IMA LSM based rules to reflect the reloaded LSM policy.
+ * We assume the rules still exist; and BUG_ON() if they don't.
+ */
+static void ima_lsm_update_rules(void)
+{
+	struct ima_rule_entry *entry, *tmp;
+	int result;
+	int i;
+
+	mutex_lock(&ima_rules_mutex);
+	list_for_each_entry_safe(entry, tmp, &ima_policy_rules, list) {
+		for (i = 0; i < MAX_LSM_RULES; i++) {
+			if (!entry->lsm[i].rule)
+				continue;
+			result = security_filter_rule_init(entry->lsm[i].type,
+							   Audit_equal,
+							   entry->lsm[i].args_p,
+							   &entry->lsm[i].rule);
+			BUG_ON(!entry->lsm[i].rule);
+		}
+	}
+	mutex_unlock(&ima_rules_mutex);
+}
+
+/**
+ * ima_match_rules - determine whether an inode matches the measure rule.
+ * @rule: a pointer to a rule
+ * @inode: a pointer to an inode
+ * @func: LIM hook identifier
+ * @mask: requested action (MAY_READ | MAY_WRITE | MAY_APPEND | MAY_EXEC)
+ *
+ * Returns true on rule match, false on failure.
+ */
+static bool ima_match_rules(struct ima_rule_entry *rule,
+			    struct inode *inode, enum ima_hooks func, int mask)
+{
+	struct task_struct *tsk = current;
+	const struct cred *cred = current_cred();
+	int i;
+
+	if ((rule->flags & IMA_FUNC) &&
+	    (rule->func != func && func != POST_SETATTR))
+		return false;
+	if ((rule->flags & IMA_MASK) &&
+	    (rule->mask != mask && func != POST_SETATTR))
+		return false;
+	if ((rule->flags & IMA_FSMAGIC)
+	    && rule->fsmagic != inode->i_sb->s_magic)
+		return false;
+	if ((rule->flags & IMA_FSUUID) &&
+	    memcmp(rule->fsuuid, inode->i_sb->s_uuid, sizeof(rule->fsuuid)))
+		return false;
+	if ((rule->flags & IMA_UID) && !uid_eq(rule->uid, cred->uid))
+		return false;
+	if ((rule->flags & IMA_FOWNER) && !uid_eq(rule->fowner, inode->i_uid))
+		return false;
+	for (i = 0; i < MAX_LSM_RULES; i++) {
+		int rc = 0;
+		u32 osid, sid;
+		int retried = 0;
+
+		if (!rule->lsm[i].rule)
+			continue;
+retry:
+		switch (i) {
+		case LSM_OBJ_USER:
+		case LSM_OBJ_ROLE:
+		case LSM_OBJ_TYPE:
+			security_inode_getsecid(inode, &osid);
+			rc = security_filter_rule_match(osid,
+							rule->lsm[i].type,
+							Audit_equal,
+							rule->lsm[i].rule,
+							NULL);
+			break;
+		case LSM_SUBJ_USER:
+		case LSM_SUBJ_ROLE:
+		case LSM_SUBJ_TYPE:
+			security_task_getsecid(tsk, &sid);
+			rc = security_filter_rule_match(sid,
+							rule->lsm[i].type,
+							Audit_equal,
+							rule->lsm[i].rule,
+							NULL);
+		default:
+			break;
+		}
+		if ((rc < 0) && (!retried)) {
+			retried = 1;
+			ima_lsm_update_rules();
+			goto retry;
+		}
+		if (!rc)
+			return false;
+	}
+	return true;
+}
+
+/*
+ * In addition to knowing that we need to appraise the file in general,
+ * we need to differentiate between calling hooks, for hook specific rules.
+ */
+static int get_subaction(struct ima_rule_entry *rule, int func)
+{
+	if (!(rule->flags & IMA_FUNC))
+		return IMA_FILE_APPRAISE;
+
+	switch (func) {
+	case MMAP_CHECK:
+		return IMA_MMAP_APPRAISE;
+	case BPRM_CHECK:
+		return IMA_BPRM_APPRAISE;
+	case MODULE_CHECK:
+		return IMA_MODULE_APPRAISE;
+	case FIRMWARE_CHECK:
+		return IMA_FIRMWARE_APPRAISE;
+	case FILE_CHECK:
+	default:
+		return IMA_FILE_APPRAISE;
+	}
+}
+
+/**
+ * ima_match_policy - decision based on LSM and other conditions
+ * @inode: pointer to an inode for which the policy decision is being made
+ * @func: IMA hook identifier
+ * @mask: requested action (MAY_READ | MAY_WRITE | MAY_APPEND | MAY_EXEC)
+ *
+ * Measure decision based on func/mask/fsmagic and LSM(subj/obj/type)
+ * conditions.
+ *
+ * (There is no need for locking when walking the policy list,
+ * as elements in the list are never deleted, nor does the list
+ * change.)
+ */
+int ima_match_policy(struct inode *inode, enum ima_hooks func, int mask,
+		     int flags)
+{
+	struct ima_rule_entry *entry;
+	int action = 0, actmask = flags | (flags << 1);
+
+	list_for_each_entry(entry, ima_rules, list) {
+
+		if (!(entry->action & actmask))
+			continue;
+
+		if (!ima_match_rules(entry, inode, func, mask))
+			continue;
+
+		action |= entry->flags & IMA_ACTION_FLAGS;
+
+		action |= entry->action & IMA_DO_MASK;
+		if (entry->action & IMA_APPRAISE)
+			action |= get_subaction(entry, func);
+
+		if (entry->action & IMA_DO_MASK)
+			actmask &= ~(entry->action | entry->action << 1);
+		else
+			actmask &= ~(entry->action | entry->action >> 1);
+
+		if (!actmask)
+			break;
+	}
+
+	return action;
+}
+
+/*
+ * Initialize the ima_policy_flag variable based on the currently
+ * loaded policy.  Based on this flag, the decision to short circuit
+ * out of a function or not call the function in the first place
+ * can be made earlier.
+ */
+void ima_update_policy_flag(void)
+{
+	struct ima_rule_entry *entry;
+
+	ima_policy_flag = 0;
+	list_for_each_entry(entry, ima_rules, list) {
+		if (entry->action & IMA_DO_MASK)
+			ima_policy_flag |= entry->action;
+	}
+
+	if (!ima_appraise)
+		ima_policy_flag &= ~IMA_APPRAISE;
+}
+
+/**
+ * ima_init_policy - initialize the default measure rules.
+ *
+ * ima_rules points to either the ima_default_rules or the
+ * the new ima_policy_rules.
+ */
+void __init ima_init_policy(void)
+{
+	int i, measure_entries, appraise_entries;
+
+	/* if !ima_use_tcb set entries = 0 so we load NO default rules */
+	measure_entries = ima_use_tcb ? ARRAY_SIZE(default_rules) : 0;
+	appraise_entries = ima_use_appraise_tcb ?
+			 ARRAY_SIZE(default_appraise_rules) : 0;
+
+	for (i = 0; i < measure_entries + appraise_entries; i++) {
+		if (i < measure_entries)
+			list_add_tail(&default_rules[i].list,
+				      &ima_default_rules);
+		else {
+			int j = i - measure_entries;
+
+			list_add_tail(&default_appraise_rules[j].list,
+				      &ima_default_rules);
+		}
+	}
+
+	ima_rules = &ima_default_rules;
+}
+
+/**
+ * ima_update_policy - update default_rules with new measure rules
+ *
+ * Called on file .release to update the default rules with a complete new
+ * policy.  Once updated, the policy is locked, no additional rules can be
+ * added to the policy.
+ */
+void ima_update_policy(void)
+{
+	static const char op[] = "policy_update";
+	const char *cause = "already-exists";
+	int result = 1;
+	int audit_info = 0;
+
+	if (ima_rules == &ima_default_rules) {
+		ima_rules = &ima_policy_rules;
+		ima_update_policy_flag();
+		cause = "complete";
+		result = 0;
+	}
+	integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL,
+			    NULL, op, cause, result, audit_info);
+}
+
+enum {
+	Opt_err = -1,
+	Opt_measure = 1, Opt_dont_measure,
+	Opt_appraise, Opt_dont_appraise,
+	Opt_audit,
+	Opt_obj_user, Opt_obj_role, Opt_obj_type,
+	Opt_subj_user, Opt_subj_role, Opt_subj_type,
+	Opt_func, Opt_mask, Opt_fsmagic, Opt_uid, Opt_fowner,
+	Opt_appraise_type, Opt_fsuuid, Opt_permit_directio
+};
+
+static match_table_t policy_tokens = {
+	{Opt_measure, "measure"},
+	{Opt_dont_measure, "dont_measure"},
+	{Opt_appraise, "appraise"},
+	{Opt_dont_appraise, "dont_appraise"},
+	{Opt_audit, "audit"},
+	{Opt_obj_user, "obj_user=%s"},
+	{Opt_obj_role, "obj_role=%s"},
+	{Opt_obj_type, "obj_type=%s"},
+	{Opt_subj_user, "subj_user=%s"},
+	{Opt_subj_role, "subj_role=%s"},
+	{Opt_subj_type, "subj_type=%s"},
+	{Opt_func, "func=%s"},
+	{Opt_mask, "mask=%s"},
+	{Opt_fsmagic, "fsmagic=%s"},
+	{Opt_fsuuid, "fsuuid=%s"},
+	{Opt_uid, "uid=%s"},
+	{Opt_fowner, "fowner=%s"},
+	{Opt_appraise_type, "appraise_type=%s"},
+	{Opt_permit_directio, "permit_directio"},
+	{Opt_err, NULL}
+};
+
+static int ima_lsm_rule_init(struct ima_rule_entry *entry,
+			     substring_t *args, int lsm_rule, int audit_type)
+{
+	int result;
+
+	if (entry->lsm[lsm_rule].rule)
+		return -EINVAL;
+
+	entry->lsm[lsm_rule].args_p = match_strdup(args);
+	if (!entry->lsm[lsm_rule].args_p)
+		return -ENOMEM;
+
+	entry->lsm[lsm_rule].type = audit_type;
+	result = security_filter_rule_init(entry->lsm[lsm_rule].type,
+					   Audit_equal,
+					   entry->lsm[lsm_rule].args_p,
+					   &entry->lsm[lsm_rule].rule);
+	if (!entry->lsm[lsm_rule].rule) {
+		kfree(entry->lsm[lsm_rule].args_p);
+		return -EINVAL;
+	}
+
+	return result;
+}
+
+static void ima_log_string(struct audit_buffer *ab, char *key, char *value)
+{
+	audit_log_format(ab, "%s=", key);
+	audit_log_untrustedstring(ab, value);
+	audit_log_format(ab, " ");
+}
+
+static int ima_parse_rule(char *rule, struct ima_rule_entry *entry)
+{
+	struct audit_buffer *ab;
+	char *p;
+	int result = 0;
+
+	ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_INTEGRITY_RULE);
+
+	entry->uid = INVALID_UID;
+	entry->fowner = INVALID_UID;
+	entry->action = UNKNOWN;
+	while ((p = strsep(&rule, " \t")) != NULL) {
+		substring_t args[MAX_OPT_ARGS];
+		int token;
+		unsigned long lnum;
+
+		if (result < 0)
+			break;
+		if ((*p == '\0') || (*p == ' ') || (*p == '\t'))
+			continue;
+		token = match_token(p, policy_tokens, args);
+		switch (token) {
+		case Opt_measure:
+			ima_log_string(ab, "action", "measure");
+
+			if (entry->action != UNKNOWN)
+				result = -EINVAL;
+
+			entry->action = MEASURE;
+			break;
+		case Opt_dont_measure:
+			ima_log_string(ab, "action", "dont_measure");
+
+			if (entry->action != UNKNOWN)
+				result = -EINVAL;
+
+			entry->action = DONT_MEASURE;
+			break;
+		case Opt_appraise:
+			ima_log_string(ab, "action", "appraise");
+
+			if (entry->action != UNKNOWN)
+				result = -EINVAL;
+
+			entry->action = APPRAISE;
+			break;
+		case Opt_dont_appraise:
+			ima_log_string(ab, "action", "dont_appraise");
+
+			if (entry->action != UNKNOWN)
+				result = -EINVAL;
+
+			entry->action = DONT_APPRAISE;
+			break;
+		case Opt_audit:
+			ima_log_string(ab, "action", "audit");
+
+			if (entry->action != UNKNOWN)
+				result = -EINVAL;
+
+			entry->action = AUDIT;
+			break;
+		case Opt_func:
+			ima_log_string(ab, "func", args[0].from);
+
+			if (entry->func)
+				result = -EINVAL;
+
+			if (strcmp(args[0].from, "FILE_CHECK") == 0)
+				entry->func = FILE_CHECK;
+			/* PATH_CHECK is for backwards compat */
+			else if (strcmp(args[0].from, "PATH_CHECK") == 0)
+				entry->func = FILE_CHECK;
+			else if (strcmp(args[0].from, "MODULE_CHECK") == 0)
+				entry->func = MODULE_CHECK;
+			else if (strcmp(args[0].from, "FIRMWARE_CHECK") == 0)
+				entry->func = FIRMWARE_CHECK;
+			else if ((strcmp(args[0].from, "FILE_MMAP") == 0)
+				|| (strcmp(args[0].from, "MMAP_CHECK") == 0))
+				entry->func = MMAP_CHECK;
+			else if (strcmp(args[0].from, "BPRM_CHECK") == 0)
+				entry->func = BPRM_CHECK;
+			else
+				result = -EINVAL;
+			if (!result)
+				entry->flags |= IMA_FUNC;
+			break;
+		case Opt_mask:
+			ima_log_string(ab, "mask", args[0].from);
+
+			if (entry->mask)
+				result = -EINVAL;
+
+			if ((strcmp(args[0].from, "MAY_EXEC")) == 0)
+				entry->mask = MAY_EXEC;
+			else if (strcmp(args[0].from, "MAY_WRITE") == 0)
+				entry->mask = MAY_WRITE;
+			else if (strcmp(args[0].from, "MAY_READ") == 0)
+				entry->mask = MAY_READ;
+			else if (strcmp(args[0].from, "MAY_APPEND") == 0)
+				entry->mask = MAY_APPEND;
+			else
+				result = -EINVAL;
+			if (!result)
+				entry->flags |= IMA_MASK;
+			break;
+		case Opt_fsmagic:
+			ima_log_string(ab, "fsmagic", args[0].from);
+
+			if (entry->fsmagic) {
+				result = -EINVAL;
+				break;
+			}
+
+			result = kstrtoul(args[0].from, 16, &entry->fsmagic);
+			if (!result)
+				entry->flags |= IMA_FSMAGIC;
+			break;
+		case Opt_fsuuid:
+			ima_log_string(ab, "fsuuid", args[0].from);
+
+			if (memchr_inv(entry->fsuuid, 0x00,
+				       sizeof(entry->fsuuid))) {
+				result = -EINVAL;
+				break;
+			}
+
+			result = blk_part_pack_uuid(args[0].from,
+						    entry->fsuuid);
+			if (!result)
+				entry->flags |= IMA_FSUUID;
+			break;
+		case Opt_uid:
+			ima_log_string(ab, "uid", args[0].from);
+
+			if (uid_valid(entry->uid)) {
+				result = -EINVAL;
+				break;
+			}
+
+			result = kstrtoul(args[0].from, 10, &lnum);
+			if (!result) {
+				entry->uid = make_kuid(current_user_ns(), (uid_t)lnum);
+				if (!uid_valid(entry->uid) || (((uid_t)lnum) != lnum))
+					result = -EINVAL;
+				else
+					entry->flags |= IMA_UID;
+			}
+			break;
+		case Opt_fowner:
+			ima_log_string(ab, "fowner", args[0].from);
+
+			if (uid_valid(entry->fowner)) {
+				result = -EINVAL;
+				break;
+			}
+
+			result = kstrtoul(args[0].from, 10, &lnum);
+			if (!result) {
+				entry->fowner = make_kuid(current_user_ns(), (uid_t)lnum);
+				if (!uid_valid(entry->fowner) || (((uid_t)lnum) != lnum))
+					result = -EINVAL;
+				else
+					entry->flags |= IMA_FOWNER;
+			}
+			break;
+		case Opt_obj_user:
+			ima_log_string(ab, "obj_user", args[0].from);
+			result = ima_lsm_rule_init(entry, args,
+						   LSM_OBJ_USER,
+						   AUDIT_OBJ_USER);
+			break;
+		case Opt_obj_role:
+			ima_log_string(ab, "obj_role", args[0].from);
+			result = ima_lsm_rule_init(entry, args,
+						   LSM_OBJ_ROLE,
+						   AUDIT_OBJ_ROLE);
+			break;
+		case Opt_obj_type:
+			ima_log_string(ab, "obj_type", args[0].from);
+			result = ima_lsm_rule_init(entry, args,
+						   LSM_OBJ_TYPE,
+						   AUDIT_OBJ_TYPE);
+			break;
+		case Opt_subj_user:
+			ima_log_string(ab, "subj_user", args[0].from);
+			result = ima_lsm_rule_init(entry, args,
+						   LSM_SUBJ_USER,
+						   AUDIT_SUBJ_USER);
+			break;
+		case Opt_subj_role:
+			ima_log_string(ab, "subj_role", args[0].from);
+			result = ima_lsm_rule_init(entry, args,
+						   LSM_SUBJ_ROLE,
+						   AUDIT_SUBJ_ROLE);
+			break;
+		case Opt_subj_type:
+			ima_log_string(ab, "subj_type", args[0].from);
+			result = ima_lsm_rule_init(entry, args,
+						   LSM_SUBJ_TYPE,
+						   AUDIT_SUBJ_TYPE);
+			break;
+		case Opt_appraise_type:
+			if (entry->action != APPRAISE) {
+				result = -EINVAL;
+				break;
+			}
+
+			ima_log_string(ab, "appraise_type", args[0].from);
+			if ((strcmp(args[0].from, "imasig")) == 0)
+				entry->flags |= IMA_DIGSIG_REQUIRED;
+			else
+				result = -EINVAL;
+			break;
+		case Opt_permit_directio:
+			entry->flags |= IMA_PERMIT_DIRECTIO;
+			break;
+		case Opt_err:
+			ima_log_string(ab, "UNKNOWN", p);
+			result = -EINVAL;
+			break;
+		}
+	}
+	if (!result && (entry->action == UNKNOWN))
+		result = -EINVAL;
+	else if (entry->func == MODULE_CHECK)
+		ima_appraise |= IMA_APPRAISE_MODULES;
+	else if (entry->func == FIRMWARE_CHECK)
+		ima_appraise |= IMA_APPRAISE_FIRMWARE;
+	audit_log_format(ab, "res=%d", !result);
+	audit_log_end(ab);
+	return result;
+}
+
+/**
+ * ima_parse_add_rule - add a rule to ima_policy_rules
+ * @rule - ima measurement policy rule
+ *
+ * Uses a mutex to protect the policy list from multiple concurrent writers.
+ * Returns the length of the rule parsed, an error code on failure
+ */
+ssize_t ima_parse_add_rule(char *rule)
+{
+	static const char op[] = "update_policy";
+	char *p;
+	struct ima_rule_entry *entry;
+	ssize_t result, len;
+	int audit_info = 0;
+
+	/* Prevent installed policy from changing */
+	if (ima_rules != &ima_default_rules) {
+		integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL,
+				    NULL, op, "already-exists",
+				    -EACCES, audit_info);
+		return -EACCES;
+	}
+
+	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+	if (!entry) {
+		integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL,
+				    NULL, op, "-ENOMEM", -ENOMEM, audit_info);
+		return -ENOMEM;
+	}
+
+	INIT_LIST_HEAD(&entry->list);
+
+	p = strsep(&rule, "\n");
+	len = strlen(p) + 1;
+
+	if (*p == '#') {
+		kfree(entry);
+		return len;
+	}
+
+	result = ima_parse_rule(p, entry);
+	if (result) {
+		kfree(entry);
+		integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL,
+				    NULL, op, "invalid-policy", result,
+				    audit_info);
+		return result;
+	}
+
+	mutex_lock(&ima_rules_mutex);
+	list_add_tail(&entry->list, &ima_policy_rules);
+	mutex_unlock(&ima_rules_mutex);
+
+	return len;
+}
+
+/* ima_delete_rules called to cleanup invalid policy */
+void ima_delete_rules(void)
+{
+	struct ima_rule_entry *entry, *tmp;
+	int i;
+
+	mutex_lock(&ima_rules_mutex);
+	list_for_each_entry_safe(entry, tmp, &ima_policy_rules, list) {
+		for (i = 0; i < MAX_LSM_RULES; i++)
+			kfree(entry->lsm[i].args_p);
+
+		list_del(&entry->list);
+		kfree(entry);
+	}
+	mutex_unlock(&ima_rules_mutex);
+}

security/integrity/ima/ima_queue.c

@@ -0,0 +1,150 @@
+/*
+ * Copyright (C) 2005,2006,2007,2008 IBM Corporation
+ *
+ * Authors:
+ * Serge Hallyn <serue@us.ibm.com>
+ * Reiner Sailer <sailer@watson.ibm.com>
+ * 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_queue.c
+ *       Implements queues that store template measurements and
+ *       maintains aggregate over the stored measurements
+ *       in the pre-configured TPM PCR (if available).
+ *       The measurement list is append-only. No entry is
+ *       ever removed or changed during the boot-cycle.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/rculist.h>
+#include <linux/slab.h>
+#include "ima.h"
+
+#define AUDIT_CAUSE_LEN_MAX 32
+
+LIST_HEAD(ima_measurements);	/* list of all measurements */
+
+/* key: inode (before secure-hashing a file) */
+struct ima_h_table ima_htable = {
+	.len = ATOMIC_LONG_INIT(0),
+	.violations = ATOMIC_LONG_INIT(0),
+	.queue[0 ... IMA_MEASURE_HTABLE_SIZE - 1] = HLIST_HEAD_INIT
+};
+
+/* mutex protects atomicity of extending measurement list
+ * and extending the TPM PCR aggregate. Since tpm_extend can take
+ * long (and the tpm driver uses a mutex), we can't use the spinlock.
+ */
+static DEFINE_MUTEX(ima_extend_list_mutex);
+
+/* lookup up the digest value in the hash table, and return the entry */
+static struct ima_queue_entry *ima_lookup_digest_entry(u8 *digest_value)
+{
+	struct ima_queue_entry *qe, *ret = NULL;
+	unsigned int key;
+	int rc;
+
+	key = ima_hash_key(digest_value);
+	rcu_read_lock();
+	hlist_for_each_entry_rcu(qe, &ima_htable.queue[key], hnext) {
+		rc = memcmp(qe->entry->digest, digest_value, TPM_DIGEST_SIZE);
+		if (rc == 0) {
+			ret = qe;
+			break;
+		}
+	}
+	rcu_read_unlock();
+	return ret;
+}
+
+/* ima_add_template_entry helper function:
+ * - Add template entry to measurement list and hash table.
+ *
+ * (Called with ima_extend_list_mutex held.)
+ */
+static int ima_add_digest_entry(struct ima_template_entry *entry)
+{
+	struct ima_queue_entry *qe;
+	unsigned int key;
+
+	qe = kmalloc(sizeof(*qe), GFP_KERNEL);
+	if (qe == NULL) {
+		pr_err("OUT OF MEMORY ERROR creating queue entry\n");
+		return -ENOMEM;
+	}
+	qe->entry = entry;
+
+	INIT_LIST_HEAD(&qe->later);
+	list_add_tail_rcu(&qe->later, &ima_measurements);
+
+	atomic_long_inc(&ima_htable.len);
+	key = ima_hash_key(entry->digest);
+	hlist_add_head_rcu(&qe->hnext, &ima_htable.queue[key]);
+	return 0;
+}
+
+static int ima_pcr_extend(const u8 *hash)
+{
+	int result = 0;
+
+	if (!ima_used_chip)
+		return result;
+
+	result = tpm_pcr_extend(TPM_ANY_NUM, CONFIG_IMA_MEASURE_PCR_IDX, hash);
+	if (result != 0)
+		pr_err("Error Communicating to TPM chip, result: %d\n", result);
+	return result;
+}
+
+/* Add template entry to the measurement list and hash table,
+ * and extend the pcr.
+ */
+int ima_add_template_entry(struct ima_template_entry *entry, int violation,
+			   const char *op, struct inode *inode,
+			   const unsigned char *filename)
+{
+	u8 digest[TPM_DIGEST_SIZE];
+	const char *audit_cause = "hash_added";
+	char tpm_audit_cause[AUDIT_CAUSE_LEN_MAX];
+	int audit_info = 1;
+	int result = 0, tpmresult = 0;
+
+	mutex_lock(&ima_extend_list_mutex);
+	if (!violation) {
+		memcpy(digest, entry->digest, sizeof(digest));
+		if (ima_lookup_digest_entry(digest)) {
+			audit_cause = "hash_exists";
+			result = -EEXIST;
+			goto out;
+		}
+	}
+
+	result = ima_add_digest_entry(entry);
+	if (result < 0) {
+		audit_cause = "ENOMEM";
+		audit_info = 0;
+		goto out;
+	}
+
+	if (violation)		/* invalidate pcr */
+		memset(digest, 0xff, sizeof(digest));
+
+	tpmresult = ima_pcr_extend(digest);
+	if (tpmresult != 0) {
+		snprintf(tpm_audit_cause, AUDIT_CAUSE_LEN_MAX, "TPM_error(%d)",
+			 tpmresult);
+		audit_cause = tpm_audit_cause;
+		audit_info = 0;
+	}
+out:
+	mutex_unlock(&ima_extend_list_mutex);
+	integrity_audit_msg(AUDIT_INTEGRITY_PCR, inode, filename,
+			    op, audit_cause, result, audit_info);
+	return result;
+}

security/integrity/ima/ima_template.c

@@ -0,0 +1,170 @@
+/*
+ * Copyright (C) 2013 Politecnico di Torino, Italy
+ *                    TORSEC group -- http://security.polito.it
+ *
+ * Author: Roberto Sassu <roberto.sassu@polito.it>
+ *
+ * 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_template.c
+ *      Helpers to manage template descriptors.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <crypto/hash_info.h>
+
+#include "ima.h"
+#include "ima_template_lib.h"
+
+static struct ima_template_desc defined_templates[] = {
+	{.name = IMA_TEMPLATE_IMA_NAME, .fmt = IMA_TEMPLATE_IMA_FMT},
+	{.name = "ima-ng", .fmt = "d-ng|n-ng"},
+	{.name = "ima-sig", .fmt = "d-ng|n-ng|sig"},
+};
+
+static struct ima_template_field supported_fields[] = {
+	{.field_id = "d", .field_init = ima_eventdigest_init,
+	 .field_show = ima_show_template_digest},
+	{.field_id = "n", .field_init = ima_eventname_init,
+	 .field_show = ima_show_template_string},
+	{.field_id = "d-ng", .field_init = ima_eventdigest_ng_init,
+	 .field_show = ima_show_template_digest_ng},
+	{.field_id = "n-ng", .field_init = ima_eventname_ng_init,
+	 .field_show = ima_show_template_string},
+	{.field_id = "sig", .field_init = ima_eventsig_init,
+	 .field_show = ima_show_template_sig},
+};
+
+static struct ima_template_desc *ima_template;
+static struct ima_template_desc *lookup_template_desc(const char *name);
+
+static int __init ima_template_setup(char *str)
+{
+	struct ima_template_desc *template_desc;
+	int template_len = strlen(str);
+
+	/*
+	 * Verify that a template with the supplied name exists.
+	 * If not, use CONFIG_IMA_DEFAULT_TEMPLATE.
+	 */
+	template_desc = lookup_template_desc(str);
+	if (!template_desc)
+		return 1;
+
+	/*
+	 * Verify whether the current hash algorithm is supported
+	 * by the 'ima' template.
+	 */
+	if (template_len == 3 && strcmp(str, IMA_TEMPLATE_IMA_NAME) == 0 &&
+	    ima_hash_algo != HASH_ALGO_SHA1 && ima_hash_algo != HASH_ALGO_MD5) {
+		pr_err("template does not support hash alg\n");
+		return 1;
+	}
+
+	ima_template = template_desc;
+	return 1;
+}
+__setup("ima_template=", ima_template_setup);
+
+static struct ima_template_desc *lookup_template_desc(const char *name)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(defined_templates); i++) {
+		if (strcmp(defined_templates[i].name, name) == 0)
+			return defined_templates + i;
+	}
+
+	return NULL;
+}
+
+static struct ima_template_field *lookup_template_field(const char *field_id)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(supported_fields); i++)
+		if (strncmp(supported_fields[i].field_id, field_id,
+			    IMA_TEMPLATE_FIELD_ID_MAX_LEN) == 0)
+			return &supported_fields[i];
+	return NULL;
+}
+
+static int template_fmt_size(const char *template_fmt)
+{
+	char c;
+	int template_fmt_len = strlen(template_fmt);
+	int i = 0, j = 0;
+
+	while (i < template_fmt_len) {
+		c = template_fmt[i];
+		if (c == '|')
+			j++;
+		i++;
+	}
+
+	return j + 1;
+}
+
+static int template_desc_init_fields(const char *template_fmt,
+				     struct ima_template_field ***fields,
+				     int *num_fields)
+{
+	char *c, *template_fmt_copy, *template_fmt_ptr;
+	int template_num_fields = template_fmt_size(template_fmt);
+	int i, result = 0;
+
+	if (template_num_fields > IMA_TEMPLATE_NUM_FIELDS_MAX)
+		return -EINVAL;
+
+	/* copying is needed as strsep() modifies the original buffer */
+	template_fmt_copy = kstrdup(template_fmt, GFP_KERNEL);
+	if (template_fmt_copy == NULL)
+		return -ENOMEM;
+
+	*fields = kzalloc(template_num_fields * sizeof(*fields), GFP_KERNEL);
+	if (*fields == NULL) {
+		result = -ENOMEM;
+		goto out;
+	}
+
+	template_fmt_ptr = template_fmt_copy;
+	for (i = 0; (c = strsep(&template_fmt_ptr, "|")) != NULL &&
+	     i < template_num_fields; i++) {
+		struct ima_template_field *f = lookup_template_field(c);
+
+		if (!f) {
+			result = -ENOENT;
+			goto out;
+		}
+		(*fields)[i] = f;
+	}
+	*num_fields = i;
+out:
+	if (result < 0) {
+		kfree(*fields);
+		*fields = NULL;
+	}
+	kfree(template_fmt_copy);
+	return result;
+}
+
+struct ima_template_desc *ima_template_desc_current(void)
+{
+	if (!ima_template)
+		ima_template =
+		    lookup_template_desc(CONFIG_IMA_DEFAULT_TEMPLATE);
+	return ima_template;
+}
+
+int __init ima_init_template(void)
+{
+	struct ima_template_desc *template = ima_template_desc_current();
+
+	return template_desc_init_fields(template->fmt,
+					 &(template->fields),
+					 &(template->num_fields));
+}

security/integrity/ima/ima_template_lib.c

@@ -0,0 +1,342 @@
+/*
+ * Copyright (C) 2013 Politecnico di Torino, Italy
+ *                    TORSEC group -- http://security.polito.it
+ *
+ * Author: Roberto Sassu <roberto.sassu@polito.it>
+ *
+ * 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_template_lib.c
+ *      Library of supported template fields.
+ */
+#include <crypto/hash_info.h>
+
+#include "ima_template_lib.h"
+
+static bool ima_template_hash_algo_allowed(u8 algo)
+{
+	if (algo == HASH_ALGO_SHA1 || algo == HASH_ALGO_MD5)
+		return true;
+
+	return false;
+}
+
+enum data_formats {
+	DATA_FMT_DIGEST = 0,
+	DATA_FMT_DIGEST_WITH_ALGO,
+	DATA_FMT_STRING,
+	DATA_FMT_HEX
+};
+
+static int ima_write_template_field_data(const void *data, const u32 datalen,
+					 enum data_formats datafmt,
+					 struct ima_field_data *field_data)
+{
+	u8 *buf, *buf_ptr;
+	u32 buflen = datalen;
+
+	if (datafmt == DATA_FMT_STRING)
+		buflen = datalen + 1;
+
+	buf = kzalloc(buflen, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	memcpy(buf, data, datalen);
+
+	/*
+	 * Replace all space characters with underscore for event names and
+	 * strings. This avoid that, during the parsing of a measurements list,
+	 * filenames with spaces or that end with the suffix ' (deleted)' are
+	 * split into multiple template fields (the space is the delimitator
+	 * character for measurements lists in ASCII format).
+	 */
+	if (datafmt == DATA_FMT_STRING) {
+		for (buf_ptr = buf; buf_ptr - buf < datalen; buf_ptr++)
+			if (*buf_ptr == ' ')
+				*buf_ptr = '_';
+	}
+
+	field_data->data = buf;
+	field_data->len = buflen;
+	return 0;
+}
+
+static void ima_show_template_data_ascii(struct seq_file *m,
+					 enum ima_show_type show,
+					 enum data_formats datafmt,
+					 struct ima_field_data *field_data)
+{
+	u8 *buf_ptr = field_data->data, buflen = field_data->len;
+
+	switch (datafmt) {
+	case DATA_FMT_DIGEST_WITH_ALGO:
+		buf_ptr = strnchr(field_data->data, buflen, ':');
+		if (buf_ptr != field_data->data)
+			seq_printf(m, "%s", field_data->data);
+
+		/* skip ':' and '\0' */
+		buf_ptr += 2;
+		buflen -= buf_ptr - field_data->data;
+	case DATA_FMT_DIGEST:
+	case DATA_FMT_HEX:
+		if (!buflen)
+			break;
+		ima_print_digest(m, buf_ptr, buflen);
+		break;
+	case DATA_FMT_STRING:
+		seq_printf(m, "%s", buf_ptr);
+		break;
+	default:
+		break;
+	}
+}
+
+static void ima_show_template_data_binary(struct seq_file *m,
+					  enum ima_show_type show,
+					  enum data_formats datafmt,
+					  struct ima_field_data *field_data)
+{
+	u32 len = (show == IMA_SHOW_BINARY_OLD_STRING_FMT) ?
+	    strlen(field_data->data) : field_data->len;
+
+	if (show != IMA_SHOW_BINARY_NO_FIELD_LEN)
+		ima_putc(m, &len, sizeof(len));
+
+	if (!len)
+		return;
+
+	ima_putc(m, field_data->data, len);
+}
+
+static void ima_show_template_field_data(struct seq_file *m,
+					 enum ima_show_type show,
+					 enum data_formats datafmt,
+					 struct ima_field_data *field_data)
+{
+	switch (show) {
+	case IMA_SHOW_ASCII:
+		ima_show_template_data_ascii(m, show, datafmt, field_data);
+		break;
+	case IMA_SHOW_BINARY:
+	case IMA_SHOW_BINARY_NO_FIELD_LEN:
+	case IMA_SHOW_BINARY_OLD_STRING_FMT:
+		ima_show_template_data_binary(m, show, datafmt, field_data);
+		break;
+	default:
+		break;
+	}
+}
+
+void ima_show_template_digest(struct seq_file *m, enum ima_show_type show,
+			      struct ima_field_data *field_data)
+{
+	ima_show_template_field_data(m, show, DATA_FMT_DIGEST, field_data);
+}
+
+void ima_show_template_digest_ng(struct seq_file *m, enum ima_show_type show,
+				 struct ima_field_data *field_data)
+{
+	ima_show_template_field_data(m, show, DATA_FMT_DIGEST_WITH_ALGO,
+				     field_data);
+}
+
+void ima_show_template_string(struct seq_file *m, enum ima_show_type show,
+			      struct ima_field_data *field_data)
+{
+	ima_show_template_field_data(m, show, DATA_FMT_STRING, field_data);
+}
+
+void ima_show_template_sig(struct seq_file *m, enum ima_show_type show,
+			   struct ima_field_data *field_data)
+{
+	ima_show_template_field_data(m, show, DATA_FMT_HEX, field_data);
+}
+
+static int ima_eventdigest_init_common(u8 *digest, u32 digestsize, u8 hash_algo,
+				       struct ima_field_data *field_data)
+{
+	/*
+	 * digest formats:
+	 *  - DATA_FMT_DIGEST: digest
+	 *  - DATA_FMT_DIGEST_WITH_ALGO: [<hash algo>] + ':' + '\0' + digest,
+	 *    where <hash algo> is provided if the hash algoritm is not
+	 *    SHA1 or MD5
+	 */
+	u8 buffer[CRYPTO_MAX_ALG_NAME + 2 + IMA_MAX_DIGEST_SIZE] = { 0 };
+	enum data_formats fmt = DATA_FMT_DIGEST;
+	u32 offset = 0;
+
+	if (hash_algo < HASH_ALGO__LAST) {
+		fmt = DATA_FMT_DIGEST_WITH_ALGO;
+		offset += snprintf(buffer, CRYPTO_MAX_ALG_NAME + 1, "%s",
+				   hash_algo_name[hash_algo]);
+		buffer[offset] = ':';
+		offset += 2;
+	}
+
+	if (digest)
+		memcpy(buffer + offset, digest, digestsize);
+	else
+		/*
+		 * If digest is NULL, the event being recorded is a violation.
+		 * Make room for the digest by increasing the offset of
+		 * IMA_DIGEST_SIZE.
+		 */
+		offset += IMA_DIGEST_SIZE;
+
+	return ima_write_template_field_data(buffer, offset + digestsize,
+					     fmt, field_data);
+}
+
+/*
+ * This function writes the digest of an event (with size limit).
+ */
+int ima_eventdigest_init(struct integrity_iint_cache *iint, struct file *file,
+			 const unsigned char *filename,
+			 struct evm_ima_xattr_data *xattr_value, int xattr_len,
+			 struct ima_field_data *field_data)
+{
+	struct {
+		struct ima_digest_data hdr;
+		char digest[IMA_MAX_DIGEST_SIZE];
+	} hash;
+	u8 *cur_digest = NULL;
+	u32 cur_digestsize = 0;
+	struct inode *inode;
+	int result;
+
+	memset(&hash, 0, sizeof(hash));
+
+	if (!iint)		/* recording a violation. */
+		goto out;
+
+	if (ima_template_hash_algo_allowed(iint->ima_hash->algo)) {
+		cur_digest = iint->ima_hash->digest;
+		cur_digestsize = iint->ima_hash->length;
+		goto out;
+	}
+
+	if (!file)		/* missing info to re-calculate the digest */
+		return -EINVAL;
+
+	inode = file_inode(file);
+	hash.hdr.algo = ima_template_hash_algo_allowed(ima_hash_algo) ?
+	    ima_hash_algo : HASH_ALGO_SHA1;
+	result = ima_calc_file_hash(file, &hash.hdr);
+	if (result) {
+		integrity_audit_msg(AUDIT_INTEGRITY_DATA, inode,
+				    filename, "collect_data",
+				    "failed", result, 0);
+		return result;
+	}
+	cur_digest = hash.hdr.digest;
+	cur_digestsize = hash.hdr.length;
+out:
+	return ima_eventdigest_init_common(cur_digest, cur_digestsize,
+					   HASH_ALGO__LAST, field_data);
+}
+
+/*
+ * This function writes the digest of an event (without size limit).
+ */
+int ima_eventdigest_ng_init(struct integrity_iint_cache *iint,
+			    struct file *file, const unsigned char *filename,
+			    struct evm_ima_xattr_data *xattr_value,
+			    int xattr_len, struct ima_field_data *field_data)
+{
+	u8 *cur_digest = NULL, hash_algo = HASH_ALGO_SHA1;
+	u32 cur_digestsize = 0;
+
+	/* If iint is NULL, we are recording a violation. */
+	if (!iint)
+		goto out;
+
+	cur_digest = iint->ima_hash->digest;
+	cur_digestsize = iint->ima_hash->length;
+
+	hash_algo = iint->ima_hash->algo;
+out:
+	return ima_eventdigest_init_common(cur_digest, cur_digestsize,
+					   hash_algo, field_data);
+}
+
+static int ima_eventname_init_common(struct integrity_iint_cache *iint,
+				     struct file *file,
+				     const unsigned char *filename,
+				     struct ima_field_data *field_data,
+				     bool size_limit)
+{
+	const char *cur_filename = NULL;
+	u32 cur_filename_len = 0;
+
+	BUG_ON(filename == NULL && file == NULL);
+
+	if (filename) {
+		cur_filename = filename;
+		cur_filename_len = strlen(filename);
+
+		if (!size_limit || cur_filename_len <= IMA_EVENT_NAME_LEN_MAX)
+			goto out;
+	}
+
+	if (file) {
+		cur_filename = file->f_dentry->d_name.name;
+		cur_filename_len = strlen(cur_filename);
+	} else
+		/*
+		 * Truncate filename if the latter is too long and
+		 * the file descriptor is not available.
+		 */
+		cur_filename_len = IMA_EVENT_NAME_LEN_MAX;
+out:
+	return ima_write_template_field_data(cur_filename, cur_filename_len,
+					     DATA_FMT_STRING, field_data);
+}
+
+/*
+ * This function writes the name of an event (with size limit).
+ */
+int ima_eventname_init(struct integrity_iint_cache *iint, struct file *file,
+		       const unsigned char *filename,
+		       struct evm_ima_xattr_data *xattr_value, int xattr_len,
+		       struct ima_field_data *field_data)
+{
+	return ima_eventname_init_common(iint, file, filename,
+					 field_data, true);
+}
+
+/*
+ * This function writes the name of an event (without size limit).
+ */
+int ima_eventname_ng_init(struct integrity_iint_cache *iint, struct file *file,
+			  const unsigned char *filename,
+			  struct evm_ima_xattr_data *xattr_value, int xattr_len,
+			  struct ima_field_data *field_data)
+{
+	return ima_eventname_init_common(iint, file, filename,
+					 field_data, false);
+}
+
+/*
+ *  ima_eventsig_init - include the file signature as part of the template data
+ */
+int ima_eventsig_init(struct integrity_iint_cache *iint, struct file *file,
+		      const unsigned char *filename,
+		      struct evm_ima_xattr_data *xattr_value, int xattr_len,
+		      struct ima_field_data *field_data)
+{
+	enum data_formats fmt = DATA_FMT_HEX;
+	int rc = 0;
+
+	if ((!xattr_value) || (xattr_value->type != EVM_IMA_XATTR_DIGSIG))
+		goto out;
+
+	rc = ima_write_template_field_data(xattr_value, xattr_len, fmt,
+					   field_data);
+out:
+	return rc;
+}

security/integrity/ima/ima_template_lib.h

@@ -0,0 +1,49 @@
+/*
+ * Copyright (C) 2013 Politecnico di Torino, Italy
+ *                    TORSEC group -- http://security.polito.it
+ *
+ * Author: Roberto Sassu <roberto.sassu@polito.it>
+ *
+ * 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_template_lib.h
+ *      Header for the library of supported template fields.
+ */
+#ifndef __LINUX_IMA_TEMPLATE_LIB_H
+#define __LINUX_IMA_TEMPLATE_LIB_H
+
+#include <linux/seq_file.h>
+#include "ima.h"
+
+void ima_show_template_digest(struct seq_file *m, enum ima_show_type show,
+			      struct ima_field_data *field_data);
+void ima_show_template_digest_ng(struct seq_file *m, enum ima_show_type show,
+				 struct ima_field_data *field_data);
+void ima_show_template_string(struct seq_file *m, enum ima_show_type show,
+			      struct ima_field_data *field_data);
+void ima_show_template_sig(struct seq_file *m, enum ima_show_type show,
+			   struct ima_field_data *field_data);
+int ima_eventdigest_init(struct integrity_iint_cache *iint, struct file *file,
+			 const unsigned char *filename,
+			 struct evm_ima_xattr_data *xattr_value, int xattr_len,
+			 struct ima_field_data *field_data);
+int ima_eventname_init(struct integrity_iint_cache *iint, struct file *file,
+		       const unsigned char *filename,
+		       struct evm_ima_xattr_data *xattr_value, int xattr_len,
+		       struct ima_field_data *field_data);
+int ima_eventdigest_ng_init(struct integrity_iint_cache *iint,
+			    struct file *file, const unsigned char *filename,
+			    struct evm_ima_xattr_data *xattr_value,
+			    int xattr_len, struct ima_field_data *field_data);
+int ima_eventname_ng_init(struct integrity_iint_cache *iint, struct file *file,
+			  const unsigned char *filename,
+			  struct evm_ima_xattr_data *xattr_value, int xattr_len,
+			  struct ima_field_data *field_data);
+int ima_eventsig_init(struct integrity_iint_cache *iint, struct file *file,
+		      const unsigned char *filename,
+		      struct evm_ima_xattr_data *xattr_value, int xattr_len,
+		      struct ima_field_data *field_data);
+#endif /* __LINUX_IMA_TEMPLATE_LIB_H */

security/integrity/integrity.h

@@ -0,0 +1,175 @@
+/*
+ * 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>
+#include <linux/key.h>
+
+/* iint action cache flags */
+#define IMA_MEASURE		0x00000001
+#define IMA_MEASURED		0x00000002
+#define IMA_APPRAISE		0x00000004
+#define IMA_APPRAISED		0x00000008
+/*#define IMA_COLLECT		0x00000010  do not use this flag */
+#define IMA_COLLECTED		0x00000020
+#define IMA_AUDIT		0x00000040
+#define IMA_AUDITED		0x00000080
+
+/* iint cache flags */
+#define IMA_ACTION_FLAGS	0xff000000
+#define IMA_DIGSIG		0x01000000
+#define IMA_DIGSIG_REQUIRED	0x02000000
+#define IMA_PERMIT_DIRECTIO	0x04000000
+#define IMA_NEW_FILE		0x08000000
+
+#define IMA_DO_MASK		(IMA_MEASURE | IMA_APPRAISE | IMA_AUDIT | \
+				 IMA_APPRAISE_SUBMASK)
+#define IMA_DONE_MASK		(IMA_MEASURED | IMA_APPRAISED | IMA_AUDITED | \
+				 IMA_COLLECTED | IMA_APPRAISED_SUBMASK)
+
+/* iint subaction appraise cache flags */
+#define IMA_FILE_APPRAISE	0x00000100
+#define IMA_FILE_APPRAISED	0x00000200
+#define IMA_MMAP_APPRAISE	0x00000400
+#define IMA_MMAP_APPRAISED	0x00000800
+#define IMA_BPRM_APPRAISE	0x00001000
+#define IMA_BPRM_APPRAISED	0x00002000
+#define IMA_MODULE_APPRAISE	0x00004000
+#define IMA_MODULE_APPRAISED	0x00008000
+#define IMA_FIRMWARE_APPRAISE	0x00010000
+#define IMA_FIRMWARE_APPRAISED	0x00020000
+#define IMA_APPRAISE_SUBMASK	(IMA_FILE_APPRAISE | IMA_MMAP_APPRAISE | \
+				 IMA_BPRM_APPRAISE | IMA_MODULE_APPRAISE | \
+				 IMA_FIRMWARE_APPRAISE)
+#define IMA_APPRAISED_SUBMASK	(IMA_FILE_APPRAISED | IMA_MMAP_APPRAISED | \
+				 IMA_BPRM_APPRAISED | IMA_MODULE_APPRAISED | \
+				 IMA_FIRMWARE_APPRAISED)
+
+enum evm_ima_xattr_type {
+	IMA_XATTR_DIGEST = 0x01,
+	EVM_XATTR_HMAC,
+	EVM_IMA_XATTR_DIGSIG,
+	IMA_XATTR_DIGEST_NG,
+	IMA_XATTR_LAST
+};
+
+struct evm_ima_xattr_data {
+	u8 type;
+	u8 digest[SHA1_DIGEST_SIZE];
+} __packed;
+
+#define IMA_MAX_DIGEST_SIZE	64
+
+struct ima_digest_data {
+	u8 algo;
+	u8 length;
+	union {
+		struct {
+			u8 unused;
+			u8 type;
+		} sha1;
+		struct {
+			u8 type;
+			u8 algo;
+		} ng;
+		u8 data[2];
+	} xattr;
+	u8 digest[0];
+} __packed;
+
+/*
+ * signature format v2 - for using with asymmetric keys
+ */
+struct signature_v2_hdr {
+	uint8_t type;		/* xattr type */
+	uint8_t version;	/* signature format version */
+	uint8_t	hash_algo;	/* Digest algorithm [enum pkey_hash_algo] */
+	uint32_t keyid;		/* IMA key identifier - not X509/PGP specific */
+	uint16_t sig_size;	/* signature size */
+	uint8_t sig[0];		/* signature payload */
+} __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 long flags;
+	enum integrity_status ima_file_status:4;
+	enum integrity_status ima_mmap_status:4;
+	enum integrity_status ima_bprm_status:4;
+	enum integrity_status ima_module_status:4;
+	enum integrity_status ima_firmware_status:4;
+	enum integrity_status evm_status:4;
+	struct ima_digest_data *ima_hash;
+};
+
+/* rbtree tree calls to lookup, insert, delete
+ * integrity data associated with an inode.
+ */
+struct integrity_iint_cache *integrity_iint_find(struct inode *inode);
+
+#define INTEGRITY_KEYRING_EVM		0
+#define INTEGRITY_KEYRING_MODULE	1
+#define INTEGRITY_KEYRING_IMA		2
+#define INTEGRITY_KEYRING_MAX		3
+
+#ifdef CONFIG_INTEGRITY_SIGNATURE
+
+int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen,
+			    const char *digest, int digestlen);
+
+int integrity_init_keyring(const unsigned int id);
+#else
+
+static inline int integrity_digsig_verify(const unsigned int id,
+					  const char *sig, int siglen,
+					  const char *digest, int digestlen)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline int integrity_init_keyring(const unsigned int id)
+{
+	return 0;
+}
+#endif /* CONFIG_INTEGRITY_SIGNATURE */
+
+#ifdef CONFIG_INTEGRITY_ASYMMETRIC_KEYS
+int asymmetric_verify(struct key *keyring, const char *sig,
+		      int siglen, const char *data, int datalen);
+#else
+static inline int asymmetric_verify(struct key *keyring, const char *sig,
+				    int siglen, const char *data, int datalen)
+{
+	return -EOPNOTSUPP;
+}
+#endif
+
+#ifdef CONFIG_INTEGRITY_AUDIT
+/* declarations */
+void integrity_audit_msg(int audit_msgno, struct inode *inode,
+			 const unsigned char *fname, const char *op,
+			 const char *cause, int result, int info);
+#else
+static inline void integrity_audit_msg(int audit_msgno, struct inode *inode,
+				       const unsigned char *fname,
+				       const char *op, const char *cause,
+				       int result, int info)
+{
+}
+#endif
+
+/* set during initialization */
+extern int iint_initialized;

security/integrity/integrity_audit.c

@@ -0,0 +1,65 @@
+/*
+ * Copyright (C) 2008 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.
+ *
+ * File: integrity_audit.c
+ *	Audit calls for the integrity subsystem
+ */
+
+#include <linux/fs.h>
+#include <linux/gfp.h>
+#include <linux/audit.h>
+#include "integrity.h"
+
+static int integrity_audit_info;
+
+/* ima_audit_setup - enable informational auditing messages */
+static int __init integrity_audit_setup(char *str)
+{
+	unsigned long audit;
+
+	if (!kstrtoul(str, 0, &audit))
+		integrity_audit_info = audit ? 1 : 0;
+	return 1;
+}
+__setup("integrity_audit=", integrity_audit_setup);
+
+void integrity_audit_msg(int audit_msgno, struct inode *inode,
+			 const unsigned char *fname, const char *op,
+			 const char *cause, int result, int audit_info)
+{
+	struct audit_buffer *ab;
+	char name[TASK_COMM_LEN];
+
+	if (!integrity_audit_info && audit_info == 1)	/* Skip info messages */
+		return;
+
+	ab = audit_log_start(current->audit_context, GFP_KERNEL, audit_msgno);
+	audit_log_format(ab, "pid=%d uid=%u auid=%u ses=%u",
+			 task_pid_nr(current),
+			 from_kuid(&init_user_ns, current_cred()->uid),
+			 from_kuid(&init_user_ns, audit_get_loginuid(current)),
+			 audit_get_sessionid(current));
+	audit_log_task_context(ab);
+	audit_log_format(ab, " op=");
+	audit_log_string(ab, op);
+	audit_log_format(ab, " cause=");
+	audit_log_string(ab, cause);
+	audit_log_format(ab, " comm=");
+	audit_log_untrustedstring(ab, get_task_comm(name, current));
+	if (fname) {
+		audit_log_format(ab, " name=");
+		audit_log_untrustedstring(ab, fname);
+	}
+	if (inode) {
+		audit_log_format(ab, " dev=");
+		audit_log_untrustedstring(ab, inode->i_sb->s_id);
+		audit_log_format(ab, " ino=%lu", inode->i_ino);
+	}
+	audit_log_format(ab, " res=%d", !result);
+	audit_log_end(ab);
+}