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authorJames Morris <jmorris@namei.org>2011-08-09 10:31:03 +1000
committerJames Morris <jmorris@namei.org>2011-08-09 10:31:03 +1000
commit5a2f3a02aea164f4f59c0c3497772090a411b462 (patch)
treed3ebe03d4f97575290087843960baa01de3acd0a /security/integrity
parent1d568ab068c021672d6cd7f50f92a3695a921ffb (diff)
parent817b54aa45db03437c6d09a7693fc6926eb8e822 (diff)
downloadlinux-linaro-stable-5a2f3a02aea164f4f59c0c3497772090a411b462.tar.gz
Merge branch 'next-evm' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/ima-2.6 into next
Conflicts: fs/attr.c Resolve conflict manually. Signed-off-by: James Morris <jmorris@namei.org>
Diffstat (limited to 'security/integrity')
-rw-r--r--security/integrity/Kconfig7
-rw-r--r--security/integrity/Makefile12
-rw-r--r--security/integrity/evm/Kconfig12
-rw-r--r--security/integrity/evm/Makefile6
-rw-r--r--security/integrity/evm/evm.h38
-rw-r--r--security/integrity/evm/evm_crypto.c216
-rw-r--r--security/integrity/evm/evm_main.c384
-rw-r--r--security/integrity/evm/evm_secfs.c108
-rw-r--r--security/integrity/iint.c171
-rw-r--r--security/integrity/ima/Kconfig1
-rw-r--r--security/integrity/ima/Makefile2
-rw-r--r--security/integrity/ima/ima.h29
-rw-r--r--security/integrity/ima/ima_api.c7
-rw-r--r--security/integrity/ima/ima_iint.c169
-rw-r--r--security/integrity/ima/ima_main.c12
-rw-r--r--security/integrity/integrity.h47
16 files changed, 1022 insertions, 199 deletions
diff --git a/security/integrity/Kconfig b/security/integrity/Kconfig
new file mode 100644
index 000000000000..4bf00acf7937
--- /dev/null
+++ b/security/integrity/Kconfig
@@ -0,0 +1,7 @@
+#
+config INTEGRITY
+ def_bool y
+ depends on IMA || EVM
+
+source security/integrity/ima/Kconfig
+source security/integrity/evm/Kconfig
diff --git a/security/integrity/Makefile b/security/integrity/Makefile
new file mode 100644
index 000000000000..0ae44aea6516
--- /dev/null
+++ b/security/integrity/Makefile
@@ -0,0 +1,12 @@
+#
+# Makefile for caching inode integrity data (iint)
+#
+
+obj-$(CONFIG_INTEGRITY) += integrity.o
+
+integrity-y := iint.o
+
+subdir-$(CONFIG_IMA) += ima
+obj-$(CONFIG_IMA) += ima/built-in.o
+subdir-$(CONFIG_EVM) += evm
+obj-$(CONFIG_EVM) += evm/built-in.o
diff --git a/security/integrity/evm/Kconfig b/security/integrity/evm/Kconfig
new file mode 100644
index 000000000000..73f654099a4b
--- /dev/null
+++ b/security/integrity/evm/Kconfig
@@ -0,0 +1,12 @@
+config EVM
+ boolean "EVM support"
+ depends on SECURITY && KEYS && ENCRYPTED_KEYS
+ select CRYPTO_HMAC
+ select CRYPTO_MD5
+ select CRYPTO_SHA1
+ default n
+ help
+ EVM protects a file's security extended attributes against
+ integrity attacks.
+
+ If you are unsure how to answer this question, answer N.
diff --git a/security/integrity/evm/Makefile b/security/integrity/evm/Makefile
new file mode 100644
index 000000000000..0787d262b9e3
--- /dev/null
+++ b/security/integrity/evm/Makefile
@@ -0,0 +1,6 @@
+#
+# Makefile for building the Extended Verification Module(EVM)
+#
+obj-$(CONFIG_EVM) += evm.o
+
+evm-y := evm_main.o evm_crypto.o evm_secfs.o
diff --git a/security/integrity/evm/evm.h b/security/integrity/evm/evm.h
new file mode 100644
index 000000000000..d320f5197437
--- /dev/null
+++ b/security/integrity/evm/evm.h
@@ -0,0 +1,38 @@
+/*
+ * Copyright (C) 2005-2010 IBM Corporation
+ *
+ * Authors:
+ * Mimi Zohar <zohar@us.ibm.com>
+ * Kylene Hall <kjhall@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 2 of the License.
+ *
+ * File: evm.h
+ *
+ */
+#include <linux/xattr.h>
+#include <linux/security.h>
+#include "../integrity.h"
+
+extern int evm_initialized;
+extern char *evm_hmac;
+
+extern struct crypto_shash *hmac_tfm;
+
+/* List of EVM protected security xattrs */
+extern char *evm_config_xattrnames[];
+
+extern int evm_init_key(void);
+extern int evm_update_evmxattr(struct dentry *dentry,
+ const char *req_xattr_name,
+ const char *req_xattr_value,
+ size_t req_xattr_value_len);
+extern int evm_calc_hmac(struct dentry *dentry, const char *req_xattr_name,
+ const char *req_xattr_value,
+ size_t req_xattr_value_len, char *digest);
+extern int evm_init_hmac(struct inode *inode, const struct xattr *xattr,
+ char *hmac_val);
+extern int evm_init_secfs(void);
+extern void evm_cleanup_secfs(void);
diff --git a/security/integrity/evm/evm_crypto.c b/security/integrity/evm/evm_crypto.c
new file mode 100644
index 000000000000..5dd5b140242c
--- /dev/null
+++ b/security/integrity/evm/evm_crypto.c
@@ -0,0 +1,216 @@
+/*
+ * Copyright (C) 2005-2010 IBM Corporation
+ *
+ * Authors:
+ * Mimi Zohar <zohar@us.ibm.com>
+ * Kylene Hall <kjhall@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 2 of the License.
+ *
+ * File: evm_crypto.c
+ * Using root's kernel master key (kmk), calculate the HMAC
+ */
+
+#include <linux/module.h>
+#include <linux/crypto.h>
+#include <linux/xattr.h>
+#include <keys/encrypted-type.h>
+#include <crypto/hash.h>
+#include "evm.h"
+
+#define EVMKEY "evm-key"
+#define MAX_KEY_SIZE 128
+static unsigned char evmkey[MAX_KEY_SIZE];
+static int evmkey_len = MAX_KEY_SIZE;
+
+struct crypto_shash *hmac_tfm;
+
+static struct shash_desc *init_desc(void)
+{
+ int rc;
+ struct shash_desc *desc;
+
+ if (hmac_tfm == NULL) {
+ hmac_tfm = crypto_alloc_shash(evm_hmac, 0, CRYPTO_ALG_ASYNC);
+ if (IS_ERR(hmac_tfm)) {
+ pr_err("Can not allocate %s (reason: %ld)\n",
+ evm_hmac, PTR_ERR(hmac_tfm));
+ rc = PTR_ERR(hmac_tfm);
+ hmac_tfm = NULL;
+ return ERR_PTR(rc);
+ }
+ }
+
+ desc = kmalloc(sizeof(*desc) + crypto_shash_descsize(hmac_tfm),
+ GFP_KERNEL);
+ if (!desc)
+ return ERR_PTR(-ENOMEM);
+
+ desc->tfm = hmac_tfm;
+ desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP;
+
+ rc = crypto_shash_setkey(hmac_tfm, evmkey, evmkey_len);
+ if (rc)
+ goto out;
+ rc = crypto_shash_init(desc);
+out:
+ if (rc) {
+ kfree(desc);
+ return ERR_PTR(rc);
+ }
+ return desc;
+}
+
+/* Protect against 'cutting & pasting' security.evm xattr, include inode
+ * specific info.
+ *
+ * (Additional directory/file metadata needs to be added for more complete
+ * protection.)
+ */
+static void hmac_add_misc(struct shash_desc *desc, struct inode *inode,
+ char *digest)
+{
+ struct h_misc {
+ unsigned long ino;
+ __u32 generation;
+ uid_t uid;
+ gid_t gid;
+ umode_t mode;
+ } hmac_misc;
+
+ memset(&hmac_misc, 0, sizeof hmac_misc);
+ hmac_misc.ino = inode->i_ino;
+ hmac_misc.generation = inode->i_generation;
+ hmac_misc.uid = inode->i_uid;
+ hmac_misc.gid = inode->i_gid;
+ hmac_misc.mode = inode->i_mode;
+ crypto_shash_update(desc, (const u8 *)&hmac_misc, sizeof hmac_misc);
+ crypto_shash_final(desc, digest);
+}
+
+/*
+ * Calculate the HMAC value across the set of protected security xattrs.
+ *
+ * Instead of retrieving the requested xattr, for performance, calculate
+ * the hmac using the requested xattr value. Don't alloc/free memory for
+ * each xattr, but attempt to re-use the previously allocated memory.
+ */
+int evm_calc_hmac(struct dentry *dentry, const char *req_xattr_name,
+ const char *req_xattr_value, size_t req_xattr_value_len,
+ char *digest)
+{
+ struct inode *inode = dentry->d_inode;
+ struct shash_desc *desc;
+ char **xattrname;
+ size_t xattr_size = 0;
+ char *xattr_value = NULL;
+ int error;
+ int size;
+
+ if (!inode->i_op || !inode->i_op->getxattr)
+ return -EOPNOTSUPP;
+ desc = init_desc();
+ if (IS_ERR(desc))
+ return PTR_ERR(desc);
+
+ error = -ENODATA;
+ for (xattrname = evm_config_xattrnames; *xattrname != NULL; xattrname++) {
+ if ((req_xattr_name && req_xattr_value)
+ && !strcmp(*xattrname, req_xattr_name)) {
+ error = 0;
+ crypto_shash_update(desc, (const u8 *)req_xattr_value,
+ req_xattr_value_len);
+ continue;
+ }
+ size = vfs_getxattr_alloc(dentry, *xattrname,
+ &xattr_value, xattr_size, GFP_NOFS);
+ if (size == -ENOMEM) {
+ error = -ENOMEM;
+ goto out;
+ }
+ if (size < 0)
+ continue;
+
+ error = 0;
+ xattr_size = size;
+ crypto_shash_update(desc, (const u8 *)xattr_value, xattr_size);
+ }
+ hmac_add_misc(desc, inode, digest);
+
+out:
+ kfree(xattr_value);
+ kfree(desc);
+ return error;
+}
+
+/*
+ * Calculate the hmac and update security.evm xattr
+ *
+ * Expects to be called with i_mutex locked.
+ */
+int evm_update_evmxattr(struct dentry *dentry, const char *xattr_name,
+ const char *xattr_value, size_t xattr_value_len)
+{
+ struct inode *inode = dentry->d_inode;
+ struct evm_ima_xattr_data xattr_data;
+ int rc = 0;
+
+ rc = evm_calc_hmac(dentry, xattr_name, xattr_value,
+ xattr_value_len, xattr_data.digest);
+ if (rc == 0) {
+ xattr_data.type = EVM_XATTR_HMAC;
+ rc = __vfs_setxattr_noperm(dentry, XATTR_NAME_EVM,
+ &xattr_data,
+ sizeof(xattr_data), 0);
+ }
+ else if (rc == -ENODATA)
+ rc = inode->i_op->removexattr(dentry, XATTR_NAME_EVM);
+ return rc;
+}
+
+int evm_init_hmac(struct inode *inode, const struct xattr *lsm_xattr,
+ char *hmac_val)
+{
+ struct shash_desc *desc;
+
+ desc = init_desc();
+ if (IS_ERR(desc)) {
+ printk(KERN_INFO "init_desc failed\n");
+ return PTR_ERR(desc);
+ }
+
+ crypto_shash_update(desc, lsm_xattr->value, lsm_xattr->value_len);
+ hmac_add_misc(desc, inode, hmac_val);
+ kfree(desc);
+ return 0;
+}
+
+/*
+ * Get the key from the TPM for the SHA1-HMAC
+ */
+int evm_init_key(void)
+{
+ struct key *evm_key;
+ struct encrypted_key_payload *ekp;
+ int rc = 0;
+
+ evm_key = request_key(&key_type_encrypted, EVMKEY, NULL);
+ if (IS_ERR(evm_key))
+ return -ENOENT;
+
+ down_read(&evm_key->sem);
+ ekp = evm_key->payload.data;
+ if (ekp->decrypted_datalen > MAX_KEY_SIZE) {
+ rc = -EINVAL;
+ goto out;
+ }
+ memcpy(evmkey, ekp->decrypted_data, ekp->decrypted_datalen);
+out:
+ /* burn the original key contents */
+ memset(ekp->decrypted_data, 0, ekp->decrypted_datalen);
+ up_read(&evm_key->sem);
+ key_put(evm_key);
+ return rc;
+}
diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c
new file mode 100644
index 000000000000..8fc5b5d7ceaa
--- /dev/null
+++ b/security/integrity/evm/evm_main.c
@@ -0,0 +1,384 @@
+/*
+ * Copyright (C) 2005-2010 IBM Corporation
+ *
+ * Author:
+ * Mimi Zohar <zohar@us.ibm.com>
+ * Kylene Hall <kjhall@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 2 of the License.
+ *
+ * File: evm_main.c
+ * implements evm_inode_setxattr, evm_inode_post_setxattr,
+ * evm_inode_removexattr, and evm_verifyxattr
+ */
+
+#include <linux/module.h>
+#include <linux/crypto.h>
+#include <linux/xattr.h>
+#include <linux/integrity.h>
+#include <linux/evm.h>
+#include <crypto/hash.h>
+#include "evm.h"
+
+int evm_initialized;
+
+char *evm_hmac = "hmac(sha1)";
+
+char *evm_config_xattrnames[] = {
+#ifdef CONFIG_SECURITY_SELINUX
+ XATTR_NAME_SELINUX,
+#endif
+#ifdef CONFIG_SECURITY_SMACK
+ XATTR_NAME_SMACK,
+#endif
+ XATTR_NAME_CAPS,
+ NULL
+};
+
+static int evm_fixmode;
+static int __init evm_set_fixmode(char *str)
+{
+ if (strncmp(str, "fix", 3) == 0)
+ evm_fixmode = 1;
+ return 0;
+}
+__setup("evm=", evm_set_fixmode);
+
+/*
+ * evm_verify_hmac - calculate and compare the HMAC with the EVM xattr
+ *
+ * Compute the HMAC on the dentry's protected set of extended attributes
+ * and compare it against the stored security.evm xattr.
+ *
+ * For performance:
+ * - use the previoulsy retrieved xattr value and length to calculate the
+ * HMAC.)
+ * - cache the verification result in the iint, when available.
+ *
+ * Returns integrity status
+ */
+static enum integrity_status evm_verify_hmac(struct dentry *dentry,
+ const char *xattr_name,
+ char *xattr_value,
+ size_t xattr_value_len,
+ struct integrity_iint_cache *iint)
+{
+ struct evm_ima_xattr_data xattr_data;
+ enum integrity_status evm_status;
+ int rc;
+
+ if (iint && iint->evm_status == INTEGRITY_PASS)
+ return iint->evm_status;
+
+ /* if status is not PASS, try to check again - against -ENOMEM */
+
+ rc = evm_calc_hmac(dentry, xattr_name, xattr_value,
+ xattr_value_len, xattr_data.digest);
+ if (rc < 0)
+ goto err_out;
+
+ xattr_data.type = EVM_XATTR_HMAC;
+ rc = vfs_xattr_cmp(dentry, XATTR_NAME_EVM, (u8 *)&xattr_data,
+ sizeof xattr_data, GFP_NOFS);
+ if (rc < 0)
+ goto err_out;
+ evm_status = INTEGRITY_PASS;
+ goto out;
+
+err_out:
+ switch (rc) {
+ case -ENODATA: /* file not labelled */
+ evm_status = INTEGRITY_NOLABEL;
+ break;
+ default:
+ evm_status = INTEGRITY_FAIL;
+ }
+out:
+ if (iint)
+ iint->evm_status = evm_status;
+ return evm_status;
+}
+
+static int evm_protected_xattr(const char *req_xattr_name)
+{
+ char **xattrname;
+ int namelen;
+ int found = 0;
+
+ namelen = strlen(req_xattr_name);
+ for (xattrname = evm_config_xattrnames; *xattrname != NULL; xattrname++) {
+ if ((strlen(*xattrname) == namelen)
+ && (strncmp(req_xattr_name, *xattrname, namelen) == 0)) {
+ found = 1;
+ break;
+ }
+ if (strncmp(req_xattr_name,
+ *xattrname + XATTR_SECURITY_PREFIX_LEN,
+ strlen(req_xattr_name)) == 0) {
+ found = 1;
+ break;
+ }
+ }
+ return found;
+}
+
+/**
+ * evm_verifyxattr - verify the integrity of the requested xattr
+ * @dentry: object of the verify xattr
+ * @xattr_name: requested xattr
+ * @xattr_value: requested xattr value
+ * @xattr_value_len: requested xattr value length
+ *
+ * Calculate the HMAC for the given dentry and verify it against the stored
+ * security.evm xattr. For performance, use the xattr value and length
+ * previously retrieved to calculate the HMAC.
+ *
+ * Returns the xattr integrity status.
+ *
+ * This function requires the caller to lock the inode's i_mutex before it
+ * is executed.
+ */
+enum integrity_status evm_verifyxattr(struct dentry *dentry,
+ const char *xattr_name,
+ void *xattr_value, size_t xattr_value_len,
+ struct integrity_iint_cache *iint)
+{
+ if (!evm_initialized || !evm_protected_xattr(xattr_name))
+ return INTEGRITY_UNKNOWN;
+
+ if (!iint) {
+ iint = integrity_iint_find(dentry->d_inode);
+ if (!iint)
+ return INTEGRITY_UNKNOWN;
+ }
+ return evm_verify_hmac(dentry, xattr_name, xattr_value,
+ xattr_value_len, iint);
+}
+EXPORT_SYMBOL_GPL(evm_verifyxattr);
+
+/*
+ * evm_protect_xattr - protect the EVM extended attribute
+ *
+ * Prevent security.evm from being modified or removed.
+ */
+static int evm_protect_xattr(struct dentry *dentry, const char *xattr_name,
+ const void *xattr_value, size_t xattr_value_len)
+{
+ if (strcmp(xattr_name, XATTR_NAME_EVM) == 0) {
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+ }
+ return 0;
+}
+
+/*
+ * evm_verify_current_integrity - verify the dentry's metadata integrity
+ * @dentry: pointer to the affected dentry
+ *
+ * Verify and return the dentry's metadata integrity. The exceptions are
+ * before EVM is initialized or in 'fix' mode.
+ */
+static enum integrity_status evm_verify_current_integrity(struct dentry *dentry)
+{
+ struct inode *inode = dentry->d_inode;
+
+ if (!evm_initialized || !S_ISREG(inode->i_mode) || evm_fixmode)
+ return 0;
+ return evm_verify_hmac(dentry, NULL, NULL, 0, NULL);
+}
+
+/**
+ * evm_inode_setxattr - protect the EVM extended attribute
+ * @dentry: pointer to the affected dentry
+ * @xattr_name: pointer to the affected extended attribute name
+ * @xattr_value: pointer to the new extended attribute value
+ * @xattr_value_len: pointer to the new extended attribute value length
+ *
+ * Updating 'security.evm' requires CAP_SYS_ADMIN privileges and that
+ * the current value is valid.
+ */
+int evm_inode_setxattr(struct dentry *dentry, const char *xattr_name,
+ const void *xattr_value, size_t xattr_value_len)
+{
+
+ enum integrity_status evm_status;
+ int ret;
+
+ ret = evm_protect_xattr(dentry, xattr_name, xattr_value,
+ xattr_value_len);
+ if (ret)
+ return ret;
+ evm_status = evm_verify_current_integrity(dentry);
+ return evm_status == INTEGRITY_PASS ? 0 : -EPERM;
+}
+
+/**
+ * evm_inode_removexattr - protect the EVM extended attribute
+ * @dentry: pointer to the affected dentry
+ * @xattr_name: pointer to the affected extended attribute name
+ *
+ * Removing 'security.evm' requires CAP_SYS_ADMIN privileges and that
+ * the current value is valid.
+ */
+int evm_inode_removexattr(struct dentry *dentry, const char *xattr_name)
+{
+ enum integrity_status evm_status;
+ int ret;
+
+ ret = evm_protect_xattr(dentry, xattr_name, NULL, 0);
+ if (ret)
+ return ret;
+ evm_status = evm_verify_current_integrity(dentry);
+ return evm_status == INTEGRITY_PASS ? 0 : -EPERM;
+}
+
+/**
+ * evm_inode_post_setxattr - update 'security.evm' to reflect the changes
+ * @dentry: pointer to the affected dentry
+ * @xattr_name: pointer to the affected extended attribute name
+ * @xattr_value: pointer to the new extended attribute value
+ * @xattr_value_len: pointer to the new extended attribute value length
+ *
+ * Update the HMAC stored in 'security.evm' to reflect the change.
+ *
+ * No need to take the i_mutex lock here, as this function is called from
+ * __vfs_setxattr_noperm(). The caller of which has taken the inode's
+ * i_mutex lock.
+ */
+void evm_inode_post_setxattr(struct dentry *dentry, const char *xattr_name,
+ const void *xattr_value, size_t xattr_value_len)
+{
+ if (!evm_initialized || !evm_protected_xattr(xattr_name))
+ return;
+
+ evm_update_evmxattr(dentry, xattr_name, xattr_value, xattr_value_len);
+ return;
+}
+
+/**
+ * evm_inode_post_removexattr - update 'security.evm' after removing the xattr
+ * @dentry: pointer to the affected dentry
+ * @xattr_name: pointer to the affected extended attribute name
+ *
+ * Update the HMAC stored in 'security.evm' to reflect removal of the xattr.
+ */
+void evm_inode_post_removexattr(struct dentry *dentry, const char *xattr_name)
+{
+ struct inode *inode = dentry->d_inode;
+
+ if (!evm_initialized || !evm_protected_xattr(xattr_name))
+ return;
+
+ mutex_lock(&inode->i_mutex);
+ evm_update_evmxattr(dentry, xattr_name, NULL, 0);
+ mutex_unlock(&inode->i_mutex);
+ return;
+}
+
+/**
+ * evm_inode_setattr - prevent updating an invalid EVM extended attribute
+ * @dentry: pointer to the affected dentry
+ */
+int evm_inode_setattr(struct dentry *dentry, struct iattr *attr)
+{
+ unsigned int ia_valid = attr->ia_valid;
+ enum integrity_status evm_status;
+
+ if (ia_valid & ~(ATTR_MODE | ATTR_UID | ATTR_GID))
+ return 0;
+ evm_status = evm_verify_current_integrity(dentry);
+ return evm_status == INTEGRITY_PASS ? 0 : -EPERM;
+}
+
+/**
+ * evm_inode_post_setattr - update 'security.evm' after modifying metadata
+ * @dentry: pointer to the affected dentry
+ * @ia_valid: for the UID and GID status
+ *
+ * For now, update the HMAC stored in 'security.evm' to reflect UID/GID
+ * changes.
+ *
+ * This function is called from notify_change(), which expects the caller
+ * to lock the inode's i_mutex.
+ */
+void evm_inode_post_setattr(struct dentry *dentry, int ia_valid)
+{
+ if (!evm_initialized)
+ return;
+
+ if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID))
+ evm_update_evmxattr(dentry, NULL, NULL, 0);
+ return;
+}
+
+/*
+ * evm_inode_init_security - initializes security.evm
+ */
+int evm_inode_init_security(struct inode *inode,
+ const struct xattr *lsm_xattr,
+ struct xattr *evm_xattr)
+{
+ struct evm_ima_xattr_data *xattr_data;
+ int rc;
+
+ if (!evm_initialized || !evm_protected_xattr(lsm_xattr->name))
+ return -EOPNOTSUPP;
+
+ xattr_data = kzalloc(sizeof(*xattr_data), GFP_NOFS);
+ if (!xattr_data)
+ return -ENOMEM;
+
+ xattr_data->type = EVM_XATTR_HMAC;
+ rc = evm_init_hmac(inode, lsm_xattr, xattr_data->digest);
+ if (rc < 0)
+ goto out;
+
+ evm_xattr->value = xattr_data;
+ evm_xattr->value_len = sizeof(*xattr_data);
+ evm_xattr->name = kstrdup(XATTR_EVM_SUFFIX, GFP_NOFS);
+ return 0;
+out:
+ kfree(xattr_data);
+ return rc;
+}
+EXPORT_SYMBOL_GPL(evm_inode_init_security);
+
+static int __init init_evm(void)
+{
+ int error;
+
+ error = evm_init_secfs();
+ if (error < 0) {
+ printk(KERN_INFO "EVM: Error registering secfs\n");
+ goto err;
+ }
+err:
+ return error;
+}
+
+static void __exit cleanup_evm(void)
+{
+ evm_cleanup_secfs();
+ if (hmac_tfm)
+ crypto_free_shash(hmac_tfm);
+}
+
+/*
+ * evm_display_config - list the EVM protected security extended attributes
+ */
+static int __init evm_display_config(void)
+{
+ char **xattrname;
+
+ for (xattrname = evm_config_xattrnames; *xattrname != NULL; xattrname++)
+ printk(KERN_INFO "EVM: %s\n", *xattrname);
+ return 0;
+}
+
+pure_initcall(evm_display_config);
+late_initcall(init_evm);
+
+MODULE_DESCRIPTION("Extended Verification Module");
+MODULE_LICENSE("GPL");
diff --git a/security/integrity/evm/evm_secfs.c b/security/integrity/evm/evm_secfs.c
new file mode 100644
index 000000000000..ac7629950578
--- /dev/null
+++ b/security/integrity/evm/evm_secfs.c
@@ -0,0 +1,108 @@
+/*
+ * Copyright (C) 2010 IBM Corporation
+ *
+ * Authors:
+ * Mimi Zohar <zohar@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 2 of the License.
+ *
+ * File: evm_secfs.c
+ * - Used to signal when key is on keyring
+ * - Get the key and enable EVM
+ */
+
+#include <linux/uaccess.h>
+#include <linux/module.h>
+#include "evm.h"
+
+static struct dentry *evm_init_tpm;
+
+/**
+ * evm_read_key - read() for <securityfs>/evm
+ *
+ * @filp: file pointer, not actually used
+ * @buf: where to put the result
+ * @count: maximum to send along
+ * @ppos: where to start
+ *
+ * Returns number of bytes read or error code, as appropriate
+ */
+static ssize_t evm_read_key(struct file *filp, char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ char temp[80];
+ ssize_t rc;
+
+ if (*ppos != 0)
+ return 0;
+
+ sprintf(temp, "%d", evm_initialized);
+ rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp));
+
+ return rc;
+}
+
+/**
+ * evm_write_key - write() for <securityfs>/evm
+ * @file: file pointer, not actually used
+ * @buf: where to get the data from
+ * @count: bytes sent
+ * @ppos: where to start
+ *
+ * Used to signal that key is on the kernel key ring.
+ * - get the integrity hmac key from the kernel key ring
+ * - create list of hmac protected extended attributes
+ * Returns number of bytes written or error code, as appropriate
+ */
+static ssize_t evm_write_key(struct file *file, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ char temp[80];
+ int i, error;
+
+ if (!capable(CAP_SYS_ADMIN) || evm_initialized)
+ return -EPERM;
+
+ if (count >= sizeof(temp) || count == 0)
+ return -EINVAL;
+
+ if (copy_from_user(temp, buf, count) != 0)
+ return -EFAULT;
+
+ temp[count] = '\0';
+
+ if ((sscanf(temp, "%d", &i) != 1) || (i != 1))
+ return -EINVAL;
+
+ error = evm_init_key();
+ if (!error) {
+ evm_initialized = 1;
+ pr_info("EVM: initialized\n");
+ } else
+ pr_err("EVM: initialization failed\n");
+ return count;
+}
+
+static const struct file_operations evm_key_ops = {
+ .read = evm_read_key,
+ .write = evm_write_key,
+};
+
+int __init evm_init_secfs(void)
+{
+ int error = 0;
+
+ evm_init_tpm = securityfs_create_file("evm", S_IRUSR | S_IRGRP,
+ NULL, NULL, &evm_key_ops);
+ if (!evm_init_tpm || IS_ERR(evm_init_tpm))
+ error = -EFAULT;
+ return error;
+}
+
+void __exit evm_cleanup_secfs(void)
+{
+ if (evm_init_tpm)
+ securityfs_remove(evm_init_tpm);
+}
diff --git a/security/integrity/iint.c b/security/integrity/iint.c
new file mode 100644
index 000000000000..0a23e075e1d2
--- /dev/null
+++ b/security/integrity/iint.c
@@ -0,0 +1,171 @@
+/*
+ * Copyright (C) 2008 IBM Corporation
+ *
+ * Authors:
+ * Mimi Zohar <zohar@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation, version 2 of the
+ * License.
+ *
+ * File: integrity_iint.c
+ * - implements the integrity hooks: integrity_inode_alloc,
+ * integrity_inode_free
+ * - cache integrity information associated with an inode
+ * using a rbtree tree.
+ */
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/spinlock.h>
+#include <linux/rbtree.h>
+#include "integrity.h"
+
+static struct rb_root integrity_iint_tree = RB_ROOT;
+static DEFINE_SPINLOCK(integrity_iint_lock);
+static struct kmem_cache *iint_cache __read_mostly;
+
+int iint_initialized;
+
+/*
+ * __integrity_iint_find - return the iint associated with an inode
+ */
+static struct integrity_iint_cache *__integrity_iint_find(struct inode *inode)
+{
+ struct integrity_iint_cache *iint;
+ struct rb_node *n = integrity_iint_tree.rb_node;
+
+ assert_spin_locked(&integrity_iint_lock);
+
+ while (n) {
+ iint = rb_entry(n, struct integrity_iint_cache, rb_node);
+
+ if (inode < iint->inode)
+ n = n->rb_left;
+ else if (inode > iint->inode)
+ n = n->rb_right;
+ else
+ break;
+ }
+ if (!n)
+ return NULL;
+
+ return iint;
+}
+
+/*
+ * integrity_iint_find - return the iint associated with an inode
+ */
+struct integrity_iint_cache *integrity_iint_find(struct inode *inode)
+{
+ struct integrity_iint_cache *iint;
+
+ if (!IS_IMA(inode))
+ return NULL;
+
+ spin_lock(&integrity_iint_lock);
+ iint = __integrity_iint_find(inode);
+ spin_unlock(&integrity_iint_lock);
+
+ return iint;
+}
+
+static void iint_free(struct integrity_iint_cache *iint)
+{
+ iint->version = 0;
+ iint->flags = 0UL;
+ kmem_cache_free(iint_cache, iint);
+}
+
+/**
+ * integrity_inode_alloc - allocate an iint associated with an inode
+ * @inode: pointer to the inode
+ */
+int integrity_inode_alloc(struct inode *inode)
+{
+ struct rb_node **p;
+ struct rb_node *new_node, *parent = NULL;
+ struct integrity_iint_cache *new_iint, *test_iint;
+ int rc;
+
+ new_iint = kmem_cache_alloc(iint_cache, GFP_NOFS);
+ if (!new_iint)
+ return -ENOMEM;
+
+ new_iint->inode = inode;
+ new_node = &new_iint->rb_node;
+
+ mutex_lock(&inode->i_mutex); /* i_flags */
+ spin_lock(&integrity_iint_lock);
+
+ p = &integrity_iint_tree.rb_node;
+ while (*p) {
+ parent = *p;
+ test_iint = rb_entry(parent, struct integrity_iint_cache,
+ rb_node);
+ rc = -EEXIST;
+ if (inode < test_iint->inode)
+ p = &(*p)->rb_left;
+ else if (inode > test_iint->inode)
+ p = &(*p)->rb_right;
+ else
+ goto out_err;
+ }
+
+ inode->i_flags |= S_IMA;
+ rb_link_node(new_node, parent, p);
+ rb_insert_color(new_node, &integrity_iint_tree);
+
+ spin_unlock(&integrity_iint_lock);
+ mutex_unlock(&inode->i_mutex); /* i_flags */
+
+ return 0;
+out_err:
+ spin_unlock(&integrity_iint_lock);
+ mutex_unlock(&inode->i_mutex); /* i_flags */
+ iint_free(new_iint);
+
+ return rc;
+}
+
+/**
+ * integrity_inode_free - called on security_inode_free
+ * @inode: pointer to the inode
+ *
+ * Free the integrity information(iint) associated with an inode.
+ */
+void integrity_inode_free(struct inode *inode)
+{
+ struct integrity_iint_cache *iint;
+
+ if (!IS_IMA(inode))
+ return;
+
+ spin_lock(&integrity_iint_lock);
+ iint = __integrity_iint_find(inode);
+ rb_erase(&iint->rb_node, &integrity_iint_tree);
+ spin_unlock(&integrity_iint_lock);
+
+ iint_free(iint);
+}
+
+static void init_once(void *foo)
+{
+ struct integrity_iint_cache *iint = foo;
+
+ memset(iint, 0, sizeof *iint);
+ iint->version = 0;
+ iint->flags = 0UL;
+ mutex_init(&iint->mutex);
+ iint->evm_status = INTEGRITY_UNKNOWN;
+}
+
+static int __init integrity_iintcache_init(void)
+{
+ iint_cache =
+ kmem_cache_create("iint_cache", sizeof(struct integrity_iint_cache),
+ 0, SLAB_PANIC, init_once);
+ iint_initialized = 1;
+ return 0;
+}
+security_initcall(integrity_iintcache_init);
diff --git a/security/integrity/ima/Kconfig b/security/integrity/ima/Kconfig
index b6ecfd4d8d78..19c053b82303 100644
--- a/security/integrity/ima/Kconfig
+++ b/security/integrity/ima/Kconfig
@@ -3,6 +3,7 @@
config IMA
bool "Integrity Measurement Architecture(IMA)"
depends on SECURITY
+ select INTEGRITY
select SECURITYFS
select CRYPTO
select CRYPTO_HMAC
diff --git a/security/integrity/ima/Makefile b/security/integrity/ima/Makefile
index 787c4cb916cd..5690c021de8f 100644
--- a/security/integrity/ima/Makefile
+++ b/security/integrity/ima/Makefile
@@ -6,4 +6,4 @@
obj-$(CONFIG_IMA) += ima.o
ima-y := ima_fs.o ima_queue.o ima_init.o ima_main.o ima_crypto.o ima_api.o \
- ima_policy.o ima_iint.o ima_audit.o
+ ima_policy.o ima_audit.o
diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index 08408bd71462..29d97af5e9a4 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -24,11 +24,13 @@
#include <linux/tpm.h>
#include <linux/audit.h>
+#include "../integrity.h"
+
enum ima_show_type { IMA_SHOW_BINARY, IMA_SHOW_ASCII };
enum tpm_pcrs { TPM_PCR0 = 0, TPM_PCR8 = 8 };
/* digest size for IMA, fits SHA1 or MD5 */
-#define IMA_DIGEST_SIZE 20
+#define IMA_DIGEST_SIZE SHA1_DIGEST_SIZE
#define IMA_EVENT_NAME_LEN_MAX 255
#define IMA_HASH_BITS 9
@@ -96,34 +98,21 @@ static inline unsigned long ima_hash_key(u8 *digest)
return hash_long(*digest, IMA_HASH_BITS);
}
-/* iint cache flags */
-#define IMA_MEASURED 0x01
-
-/* integrity data associated with an inode */
-struct ima_iint_cache {
- struct rb_node rb_node; /* rooted in ima_iint_tree */
- struct inode *inode; /* back pointer to inode in question */
- u64 version; /* track inode changes */
- unsigned char flags;
- u8 digest[IMA_DIGEST_SIZE];
- struct mutex mutex; /* protects: version, flags, digest */
-};
-
/* LIM API function definitions */
int ima_must_measure(struct inode *inode, int mask, int function);
-int ima_collect_measurement(struct ima_iint_cache *iint, struct file *file);
-void ima_store_measurement(struct ima_iint_cache *iint, struct file *file,
+int ima_collect_measurement(struct integrity_iint_cache *iint,
+ struct file *file);
+void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file,
const unsigned char *filename);
int ima_store_template(struct ima_template_entry *entry, int violation,
struct inode *inode);
-void ima_template_show(struct seq_file *m, void *e,
- enum ima_show_type show);
+void ima_template_show(struct seq_file *m, void *e, enum ima_show_type show);
/* rbtree tree calls to lookup, insert, delete
* integrity data associated with an inode.
*/
-struct ima_iint_cache *ima_iint_insert(struct inode *inode);
-struct ima_iint_cache *ima_iint_find(struct inode *inode);
+struct integrity_iint_cache *integrity_iint_insert(struct inode *inode);
+struct integrity_iint_cache *integrity_iint_find(struct inode *inode);
/* IMA policy related functions */
enum ima_hooks { FILE_CHECK = 1, FILE_MMAP, BPRM_CHECK };
diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c
index da36d2c085a4..0d50df04ccc4 100644
--- a/security/integrity/ima/ima_api.c
+++ b/security/integrity/ima/ima_api.c
@@ -126,7 +126,8 @@ int ima_must_measure(struct inode *inode, int mask, int function)
*
* Return 0 on success, error code otherwise
*/
-int ima_collect_measurement(struct ima_iint_cache *iint, struct file *file)
+int ima_collect_measurement(struct integrity_iint_cache *iint,
+ struct file *file)
{
int result = -EEXIST;
@@ -156,8 +157,8 @@ int ima_collect_measurement(struct ima_iint_cache *iint, struct file *file)
*
* Must be called with iint->mutex held.
*/
-void ima_store_measurement(struct ima_iint_cache *iint, struct file *file,
- const unsigned char *filename)
+void ima_store_measurement(struct integrity_iint_cache *iint,
+ struct file *file, const unsigned char *filename)
{
const char *op = "add_template_measure";
const char *audit_cause = "ENOMEM";
diff --git a/security/integrity/ima/ima_iint.c b/security/integrity/ima/ima_iint.c
deleted file mode 100644
index 4ae73040ab7b..000000000000
--- a/security/integrity/ima/ima_iint.c
+++ /dev/null
@@ -1,169 +0,0 @@
-/*
- * Copyright (C) 2008 IBM Corporation
- *
- * Authors:
- * Mimi Zohar <zohar@us.ibm.com>
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation, version 2 of the
- * License.
- *
- * File: ima_iint.c
- * - implements the IMA hooks: ima_inode_alloc, ima_inode_free
- * - cache integrity information associated with an inode
- * using a rbtree tree.
- */
-#include <linux/slab.h>
-#include <linux/module.h>
-#include <linux/spinlock.h>
-#include <linux/rbtree.h>
-#include "ima.h"
-
-static struct rb_root ima_iint_tree = RB_ROOT;
-static DEFINE_SPINLOCK(ima_iint_lock);
-static struct kmem_cache *iint_cache __read_mostly;
-
-int iint_initialized = 0;
-
-/*
- * __ima_iint_find - return the iint associated with an inode
- */
-static struct ima_iint_cache *__ima_iint_find(struct inode *inode)
-{
- struct ima_iint_cache *iint;
- struct rb_node *n = ima_iint_tree.rb_node;
-
- assert_spin_locked(&ima_iint_lock);
-
- while (n) {
- iint = rb_entry(n, struct ima_iint_cache, rb_node);
-
- if (inode < iint->inode)
- n = n->rb_left;
- else if (inode > iint->inode)
- n = n->rb_right;
- else
- break;
- }
- if (!n)
- return NULL;
-
- return iint;
-}
-
-/*
- * ima_iint_find - return the iint associated with an inode
- */
-struct ima_iint_cache *ima_iint_find(struct inode *inode)
-{
- struct ima_iint_cache *iint;
-
- if (!IS_IMA(inode))
- return NULL;
-
- spin_lock(&ima_iint_lock);
- iint = __ima_iint_find(inode);
- spin_unlock(&ima_iint_lock);
-
- return iint;
-}
-
-static void iint_free(struct ima_iint_cache *iint)
-{
- iint->version = 0;
- iint->flags = 0UL;
- kmem_cache_free(iint_cache, iint);
-}
-
-/**
- * ima_inode_alloc - allocate an iint associated with an inode
- * @inode: pointer to the inode
- */
-int ima_inode_alloc(struct inode *inode)
-{
- struct rb_node **p;
- struct rb_node *new_node, *parent = NULL;
- struct ima_iint_cache *new_iint, *test_iint;
- int rc;
-
- new_iint = kmem_cache_alloc(iint_cache, GFP_NOFS);
- if (!new_iint)
- return -ENOMEM;
-
- new_iint->inode = inode;
- new_node = &new_iint->rb_node;
-
- mutex_lock(&inode->i_mutex); /* i_flags */
- spin_lock(&ima_iint_lock);
-
- p = &ima_iint_tree.rb_node;
- while (*p) {
- parent = *p;
- test_iint = rb_entry(parent, struct ima_iint_cache, rb_node);
-
- rc = -EEXIST;
- if (inode < test_iint->inode)
- p = &(*p)->rb_left;
- else if (inode > test_iint->inode)
- p = &(*p)->rb_right;
- else
- goto out_err;
- }
-
- inode->i_flags |= S_IMA;
- rb_link_node(new_node, parent, p);
- rb_insert_color(new_node, &ima_iint_tree);
-
- spin_unlock(&ima_iint_lock);
- mutex_unlock(&inode->i_mutex); /* i_flags */
-
- return 0;
-out_err:
- spin_unlock(&ima_iint_lock);
- mutex_unlock(&inode->i_mutex); /* i_flags */
- iint_free(new_iint);
-
- return rc;
-}
-
-/**
- * ima_inode_free - called on security_inode_free
- * @inode: pointer to the inode
- *
- * Free the integrity information(iint) associated with an inode.
- */
-void ima_inode_free(struct inode *inode)
-{
- struct ima_iint_cache *iint;
-
- if (!IS_IMA(inode))
- return;
-
- spin_lock(&ima_iint_lock);
- iint = __ima_iint_find(inode);
- rb_erase(&iint->rb_node, &ima_iint_tree);
- spin_unlock(&ima_iint_lock);
-
- iint_free(iint);
-}
-
-static void init_once(void *foo)
-{
- struct ima_iint_cache *iint = foo;
-
- memset(iint, 0, sizeof *iint);
- iint->version = 0;
- iint->flags = 0UL;
- mutex_init(&iint->mutex);
-}
-
-static int __init ima_iintcache_init(void)
-{
- iint_cache =
- kmem_cache_create("iint_cache", sizeof(struct ima_iint_cache), 0,
- SLAB_PANIC, init_once);
- iint_initialized = 1;
- return 0;
-}
-security_initcall(ima_iintcache_init);
diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
index 26b46ff74663..42dc27007fdd 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -82,7 +82,7 @@ out:
"open_writers");
}
-static void ima_check_last_writer(struct ima_iint_cache *iint,
+static void ima_check_last_writer(struct integrity_iint_cache *iint,
struct inode *inode,
struct file *file)
{
@@ -105,12 +105,12 @@ static void ima_check_last_writer(struct ima_iint_cache *iint,
void ima_file_free(struct file *file)
{
struct inode *inode = file->f_dentry->d_inode;
- struct ima_iint_cache *iint;
+ struct integrity_iint_cache *iint;
if (!iint_initialized || !S_ISREG(inode->i_mode))
return;
- iint = ima_iint_find(inode);
+ iint = integrity_iint_find(inode);
if (!iint)
return;
@@ -121,7 +121,7 @@ static int process_measurement(struct file *file, const unsigned char *filename,
int mask, int function)
{
struct inode *inode = file->f_dentry->d_inode;
- struct ima_iint_cache *iint;
+ struct integrity_iint_cache *iint;
int rc = 0;
if (!ima_initialized || !S_ISREG(inode->i_mode))
@@ -131,9 +131,9 @@ static int process_measurement(struct file *file, const unsigned char *filename,
if (rc != 0)
return rc;
retry:
- iint = ima_iint_find(inode);
+ iint = integrity_iint_find(inode);
if (!iint) {
- rc = ima_inode_alloc(inode);
+ rc = integrity_inode_alloc(inode);
if (!rc || rc == -EEXIST)
goto retry;
return rc;
diff --git a/security/integrity/integrity.h b/security/integrity/integrity.h
new file mode 100644
index 000000000000..880bbee2f534
--- /dev/null
+++ b/security/integrity/integrity.h
@@ -0,0 +1,47 @@
+/*
+ * Copyright (C) 2009-2010 IBM Corporation
+ *
+ * Authors:
+ * Mimi Zohar <zohar@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation, version 2 of the
+ * License.
+ *
+ */
+
+#include <linux/types.h>
+#include <linux/integrity.h>
+#include <crypto/sha.h>
+
+/* iint cache flags */
+#define IMA_MEASURED 0x01
+
+enum evm_ima_xattr_type {
+ IMA_XATTR_DIGEST = 0x01,
+ EVM_XATTR_HMAC,
+ EVM_IMA_XATTR_DIGSIG,
+};
+
+struct evm_ima_xattr_data {
+ u8 type;
+ u8 digest[SHA1_DIGEST_SIZE];
+} __attribute__((packed));
+
+/* integrity data associated with an inode */
+struct integrity_iint_cache {
+ struct rb_node rb_node; /* rooted in integrity_iint_tree */
+ struct inode *inode; /* back pointer to inode in question */
+ u64 version; /* track inode changes */
+ unsigned char flags;
+ u8 digest[SHA1_DIGEST_SIZE];
+ struct mutex mutex; /* protects: version, flags, digest */
+ enum integrity_status evm_status;
+};
+
+/* rbtree tree calls to lookup, insert, delete
+ * integrity data associated with an inode.
+ */
+struct integrity_iint_cache *integrity_iint_insert(struct inode *inode);
+struct integrity_iint_cache *integrity_iint_find(struct inode *inode);