[PATCH v7 02/16] integrity: move ima inode integrity data management

Mimi Zohar
2011-06-29T19:52:11Z

Move the inode integrity data(iint) management up to the integrity directory
in order to share the iint among the different integrity models.

Changelog:
- don't define MAX_DIGEST_SIZE
- rename several globally visible 'ima_' prefixed functions, structs,
locks, etc to 'integrity_'
- replace '20' with SHA1_DIGEST_SIZE
- reflect location change in appropriate Kconfig and Makefiles
- remove unnecessary initialization of iint_initialized to 0
- rebased on current ima_iint.c
- define integrity_iint_store/lock as static

There should be no other functional changes.

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Acked-by: Serge Hallyn <serge.hallyn@ubuntu.com>
---
include/linux/ima.h | 13 ---
include/linux/integrity.h | 30 +++++++
security/Kconfig | 2 +-
security/Makefile | 4 +-
security/integrity/Kconfig | 6 ++
security/integrity/Makefile | 10 ++
security/integrity/iint.c | 170 +++++++++++++++++++++++++++++++++++++
security/integrity/ima/Kconfig | 1 +
security/integrity/ima/Makefile | 2 +-
security/integrity/ima/ima.h | 29 ++-----
security/integrity/ima/ima_api.c | 7 +-
security/integrity/ima/ima_iint.c | 169 ------------------------------------
security/integrity/ima/ima_main.c | 12 ++--
security/integrity/integrity.h | 35 ++++++++
security/security.c | 3 +-
15 files changed, 277 insertions(+), 216 deletions(-)
create mode 100644 include/linux/integrity.h
create mode 100644 security/integrity/Kconfig
create mode 100644 security/integrity/Makefile
create mode 100644 security/integrity/iint.c
delete mode 100644 security/integrity/ima/ima_iint.c
create mode 100644 security/integrity/integrity.h

diff --git a/include/linux/ima.h b/include/linux/ima.h
index 09e6e62..6ac8e50 100644
--- a/include/linux/ima.h
+++ b/include/linux/ima.h
@@ -15,8 +15,6 @@ struct linux_binprm;

#ifdef CONFIG_IMA
extern int ima_bprm_check(struct linux_binprm *bprm);
-extern int ima_inode_alloc(struct inode *inode);
-extern void ima_inode_free(struct inode *inode);
extern int ima_file_check(struct file *file, int mask);
extern void ima_file_free(struct file *file);
extern int ima_file_mmap(struct file *file, unsigned long prot);
@@ -27,16 +25,6 @@ static inline int ima_bprm_check(struct linux_binprm *bprm)
return 0;
}

-static inline int ima_inode_alloc(struct inode *inode)
-{
- return 0;
-}
-
-static inline void ima_inode_free(struct inode *inode)
-{
- return;
-}
-
static inline int ima_file_check(struct file *file, int mask)
{
return 0;
@@ -51,6 +39,5 @@ static inline int ima_file_mmap(struct file *file, unsigned long prot)
{
return 0;
}
-
#endif /* CONFIG_IMA_H */
#endif /* _LINUX_IMA_H */
diff --git a/include/linux/integrity.h b/include/linux/integrity.h
new file mode 100644
index 0000000..9059812
--- /dev/null
+++ b/include/linux/integrity.h
@@ -0,0 +1,30 @@
+/*
+ * Copyright (C) 2009 IBM Corporation
+ * Author: Mimi Zohar <zohar@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 2 of the License.
+ */
+
+#ifndef _LINUX_INTEGRITY_H
+#define _LINUX_INTEGRITY_H
+
+#include <linux/fs.h>
+
+#ifdef CONFIG_INTEGRITY
+extern int integrity_inode_alloc(struct inode *inode);
+extern void integrity_inode_free(struct inode *inode);
+
+#else
+static inline int integrity_inode_alloc(struct inode *inode)
+{
+ return 0;
+}
+
+static inline void integrity_inode_free(struct inode *inode)
+{
+ return;
+}
+#endif /* CONFIG_INTEGRITY_H */
+#endif /* _LINUX_INTEGRITY_H */
diff --git a/security/Kconfig b/security/Kconfig
index e0f08b5..22847a8 100644
--- a/security/Kconfig
+++ b/security/Kconfig
@@ -186,7 +186,7 @@ source security/smack/Kconfig
source security/tomoyo/Kconfig
source security/apparmor/Kconfig

-source security/integrity/ima/Kconfig
+source security/integrity/Kconfig

choice
prompt "Default security module"
diff --git a/security/Makefile b/security/Makefile
index 8bb0fe9..a5e502f 100644
--- a/security/Makefile
+++ b/security/Makefile
@@ -24,5 +24,5 @@ obj-$(CONFIG_SECURITY_APPARMOR) += apparmor/built-in.o
obj-$(CONFIG_CGROUP_DEVICE) += device_cgroup.o

# Object integrity file lists
-subdir-$(CONFIG_IMA) += integrity/ima
-obj-$(CONFIG_IMA) += integrity/ima/built-in.o
+subdir-$(CONFIG_INTEGRITY) += integrity
+obj-$(CONFIG_INTEGRITY) += integrity/built-in.o
diff --git a/security/integrity/Kconfig b/security/integrity/Kconfig
new file mode 100644
index 0000000..2704691
--- /dev/null
+++ b/security/integrity/Kconfig
@@ -0,0 +1,6 @@
+#
+config INTEGRITY
+ def_bool y
+ depends on IMA
+
+source security/integrity/ima/Kconfig
diff --git a/security/integrity/Makefile b/security/integrity/Makefile
new file mode 100644
index 0000000..6eddd61
--- /dev/null
+++ b/security/integrity/Makefile
@@ -0,0 +1,10 @@
+#
+# 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
diff --git a/security/integrity/iint.c b/security/integrity/iint.c
new file mode 100644
index 0000000..d17de48
--- /dev/null
+++ b/security/integrity/iint.c
@@ -0,0 +1,170 @@
+/*
+ * 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);
+}
+
+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 b6ecfd4..19c053b 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 787c4cb..5690c02 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 08408bd..29d97af 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 da36d2c..0d50df0 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 4ae7304..0000000
--- 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 39d66dc..25f9fe7 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 0000000..7351836
--- /dev/null
+++ b/security/integrity/integrity.h
@@ -0,0 +1,35 @@
+/*
+ * 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
+
+/* 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 */
+};
+
+/* 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);
diff --git a/security/security.c b/security/security.c
index 3464d58..947fdcf 100644
--- a/security/security.c
+++ b/security/security.c
@@ -16,6 +16,7 @@
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/security.h>
+#include <linux/integrity.h>
#include <linux/ima.h>

#define MAX_LSM_XATTR 1
@@ -336,7 +337,7 @@ int security_inode_alloc(struct inode *inode)

void security_inode_free(struct inode *inode)
{
- ima_inode_free(inode);
+ integrity_inode_free(inode);
security_ops->inode_free_security(inode);
}

--
1.7.3.4