* [PATCH 3/4] integrity: Linux Integrity Module(LIM)
2008-10-07 18:00 [PATCH 0/4] integrity Mimi Zohar
2008-10-07 18:00 ` [PATCH 1/4] integrity: TPM internel kernel interface Mimi Zohar
2008-10-07 18:00 ` [PATCH 2/4] integrity: special fs magic Mimi Zohar
@ 2008-10-07 18:00 ` Mimi Zohar
2008-10-07 18:00 ` [PATCH 4/4] integrity: IMA as an integrity service provider Mimi Zohar
2008-10-08 4:56 ` [PATCH 0/4] integrity James Morris
4 siblings, 0 replies; 35+ messages in thread
From: Mimi Zohar @ 2008-10-07 18:00 UTC (permalink / raw)
To: linux-kernel
Cc: Mimi Zohar, Andrew Morton, James Morris, Christoph Hellwig,
Al Viro, David Safford, Serge Hallyn, Mimi Zohar
Concern was raised on the lkml mailing list, about adding i_integrity
to the inode structure. This patch adds a comment clarifying that
i_integrity is only included in the inode if INTEGRITY is configured.
This version resolves the merge issues resulting from the removal of
the nameidata parameter to inode_permission().
- Moved the integrity_inode_permission() call from inode_permission()
to vfs_inode_permission() and file_inode_permission().
- Replaced the inode and nameidata parameters with file and path
parameters to integrity_inode_permission().
This patch is a redesign of the integrity framework, which address a
number of issues, including
- generalizing the measurement API beyond just inode measurements.
- separation of the measurement into distinct collection, appraisal,
and commitment phases, for greater flexibility.
Extended Verification Module(EVM) and the Integrity Measurement
Architecture(IMA) were originally implemented as an LSM module. Based
on discussions on the LSM mailing list, a decision was made that the
LSM hooks should only be used to enforce mandatory access control
decisions and a new set of hooks should be defined specifically for
integrity.
EVM/IMA was limited to verifying and measuring a file's (i.e. an inode)
integrity and the metadata associated with it. Current research is
looking into other types of integrity measurements. (i.e. "Linux kernel
integrity measurement using contextual inspection", by Peter A. Loscocco,
Perry W. Wilson, J. Aaron Pendergrass, C. Durward McDonell,
http://doi.acm.org/10.1145/1314354.1314362). As a result, a requirement
of the new integrity framework is support for different types of integrity
measurements.
This patch provides an integrity framework(api and hooks) and placement
of the integrity hooks in the appropriate places in the fs directory.
Collecting, appraising, and storing of file and other types of integrity
data is supported. Multiple integrity templates, which implement the
integrity API, may register themselves. For now, only a single integrity
provider can register itself for the integrity hooks. (Support for multiple
providers registering themselves for the integrity hooks would require
some form of stacking.)
The six integrity hooks are:
inode_permission, inode_alloc_integrity, inode_free_integrity,
bprm_check_integrity, file_free_integrity, file_mmap
The five integrity API calls provided are:
integrity_must_measure, integrity_collect_measurement,
integrity_appraise_measurement, integrity_store_measurement,
and integrity_display_template.
The type of integrity data being collected, appraised, stored, or
displayed is template dependent.
(Details on the calls and their exact arguments are in linux/integrity.h,
included in the patch.)
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
---
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index e7bea3e..8a30e55 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -44,6 +44,7 @@ parameter is applicable:
FB The frame buffer device is enabled.
HW Appropriate hardware is enabled.
IA-64 IA-64 architecture is enabled.
+ INTEGRITY Integrity support is enabled.
IOSCHED More than one I/O scheduler is enabled.
IP_PNP IP DHCP, BOOTP, or RARP is enabled.
ISAPNP ISA PnP code is enabled.
@@ -878,6 +879,11 @@ and is between 256 and 4096 characters. It is defined in the file
inport.irq= [HW] Inport (ATI XL and Microsoft) busmouse driver
Format: <irq>
+ integrity_audit= [INTEGRITY]
+ Format: { "0" | "1" }
+ 0 -- disable integrity auditing messages.
+ 1 -- enable integrity auditing messages. (Default)
+
inttest= [IA64]
iommu= [x86]
diff --git a/fs/exec.c b/fs/exec.c
index 32993be..ec00043 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -45,6 +45,7 @@
#include <linux/proc_fs.h>
#include <linux/mount.h>
#include <linux/security.h>
+#include <linux/integrity.h>
#include <linux/syscalls.h>
#include <linux/tsacct_kern.h>
#include <linux/cn_proc.h>
@@ -1204,6 +1205,9 @@ int search_binary_handler(struct linux_binprm *bprm,struct pt_regs *regs)
retval = security_bprm_check(bprm);
if (retval)
return retval;
+ retval = integrity_bprm_check(bprm);
+ if (retval)
+ return retval;
/* kernel module loader fixup */
/* so we don't try to load run modprobe in kernel space. */
diff --git a/fs/file_table.c b/fs/file_table.c
index f45a449..8ba48aa 100644
--- a/fs/file_table.c
+++ b/fs/file_table.c
@@ -13,6 +13,7 @@
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/security.h>
+#include <linux/integrity.h>
#include <linux/eventpoll.h>
#include <linux/rcupdate.h>
#include <linux/mount.h>
@@ -272,6 +273,7 @@ void __fput(struct file *file)
if (file->f_op && file->f_op->release)
file->f_op->release(inode, file);
security_file_free(file);
+ integrity_file_free(file);
if (unlikely(S_ISCHR(inode->i_mode) && inode->i_cdev != NULL))
cdev_put(inode->i_cdev);
fops_put(file->f_op);
@@ -343,6 +345,7 @@ void put_filp(struct file *file)
{
if (atomic_long_dec_and_test(&file->f_count)) {
security_file_free(file);
+ integrity_file_free(file);
file_kill(file);
file_free(file);
}
diff --git a/fs/inode.c b/fs/inode.c
index b6726f6..424de21 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -17,6 +17,7 @@
#include <linux/hash.h>
#include <linux/swap.h>
#include <linux/security.h>
+#include <linux/integrity.h>
#include <linux/pagemap.h>
#include <linux/cdev.h>
#include <linux/bootmem.h>
@@ -143,13 +144,12 @@ static struct inode *alloc_inode(struct super_block *sb)
inode->i_cdev = NULL;
inode->i_rdev = 0;
inode->dirtied_when = 0;
- if (security_inode_alloc(inode)) {
- if (inode->i_sb->s_op->destroy_inode)
- inode->i_sb->s_op->destroy_inode(inode);
- else
- kmem_cache_free(inode_cachep, (inode));
- return NULL;
- }
+ if (security_inode_alloc(inode))
+ goto out_free_inode;
+
+ /* allocate, attach and initialize an i_integrity */
+ if (integrity_inode_alloc(inode))
+ goto out_free_inode;
spin_lock_init(&inode->i_lock);
lockdep_set_class(&inode->i_lock, &sb->s_type->i_lock_key);
@@ -184,12 +184,20 @@ static struct inode *alloc_inode(struct super_block *sb)
inode->i_mapping = mapping;
}
return inode;
+
+out_free_inode:
+ if (inode->i_sb->s_op->destroy_inode)
+ inode->i_sb->s_op->destroy_inode(inode);
+ else
+ kmem_cache_free(inode_cachep, (inode));
+ return NULL;
}
void destroy_inode(struct inode *inode)
{
BUG_ON(inode_has_buffers(inode));
security_inode_free(inode);
+ integrity_inode_free(inode);
if (inode->i_sb->s_op->destroy_inode)
inode->i_sb->s_op->destroy_inode(inode);
else
diff --git a/fs/namei.c b/fs/namei.c
index 4ea63ed..cd952b2 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -24,6 +24,7 @@
#include <linux/fsnotify.h>
#include <linux/personality.h>
#include <linux/security.h>
+#include <linux/integrity.h>
#include <linux/syscalls.h>
#include <linux/mount.h>
#include <linux/audit.h>
@@ -289,7 +290,14 @@ int inode_permission(struct inode *inode, int mask)
*/
int vfs_permission(struct nameidata *nd, int mask)
{
- return inode_permission(nd->path.dentry->d_inode, mask);
+ int retval;
+
+ retval = inode_permission(nd->path.dentry->d_inode, mask);
+ if (retval)
+ return retval;
+ return integrity_inode_permission(NULL, &nd->path,
+ mask & (MAY_READ | MAY_WRITE |
+ MAY_EXEC));
}
/**
@@ -306,7 +314,14 @@ int vfs_permission(struct nameidata *nd, int mask)
*/
int file_permission(struct file *file, int mask)
{
- return inode_permission(file->f_path.dentry->d_inode, mask);
+ int retval;
+
+ retval = inode_permission(file->f_path.dentry->d_inode, mask);
+ if (retval)
+ return retval;
+ return integrity_inode_permission(file, NULL,
+ mask & (MAY_READ | MAY_WRITE |
+ MAY_EXEC));
}
/*
diff --git a/include/linux/audit.h b/include/linux/audit.h
index 6272a39..90e8c38 100644
--- a/include/linux/audit.h
+++ b/include/linux/audit.h
@@ -123,6 +123,11 @@
#define AUDIT_LAST_KERN_ANOM_MSG 1799
#define AUDIT_ANOM_PROMISCUOUS 1700 /* Device changed promiscuous mode */
#define AUDIT_ANOM_ABEND 1701 /* Process ended abnormally */
+#define AUDIT_INTEGRITY_DATA 1800 /* Data integrity verification */
+#define AUDIT_INTEGRITY_METADATA 1801 /* Metadata integrity verification */
+#define AUDIT_INTEGRITY_STATUS 1802 /* Integrity enable status */
+#define AUDIT_INTEGRITY_HASH 1803 /* Integrity HASH type */
+#define AUDIT_INTEGRITY_PCR 1804 /* PCR invalidation msgs */
#define AUDIT_KERNEL 2000 /* Asynchronous audit record. NOT A REQUEST. */
@@ -440,6 +445,8 @@ extern int audit_set_loginuid(struct task_struct *task, uid_t loginuid);
#define audit_get_loginuid(t) ((t)->loginuid)
#define audit_get_sessionid(t) ((t)->sessionid)
extern void audit_log_task_context(struct audit_buffer *ab);
+extern void audit_log_inode_context(struct audit_buffer *ab,
+ struct inode *inode);
extern int __audit_ipc_obj(struct kern_ipc_perm *ipcp);
extern int __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, mode_t mode);
extern int audit_bprm(struct linux_binprm *bprm);
@@ -520,6 +527,7 @@ extern int audit_signals;
#define audit_get_loginuid(t) (-1)
#define audit_get_sessionid(t) (-1)
#define audit_log_task_context(b) do { ; } while (0)
+#define audit_log_inode_context(b, a) do { } while (0)
#define audit_ipc_obj(i) ({ 0; })
#define audit_ipc_set_perm(q,u,g,m) ({ 0; })
#define audit_bprm(p) ({ 0; })
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 580b513..342922f 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -680,6 +680,9 @@ struct inode {
#ifdef CONFIG_SECURITY
void *i_security;
#endif
+#ifdef CONFIG_INTEGRITY
+ void *i_integrity;
+#endif
void *i_private; /* fs or device private pointer */
};
diff --git a/include/linux/integrity.h b/include/linux/integrity.h
new file mode 100644
index 0000000..d9c1d64
--- /dev/null
+++ b/include/linux/integrity.h
@@ -0,0 +1,182 @@
+/*
+ * Copyright (C) 2005,2006,2007,2008 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.
+ */
+
+#ifndef _LINUX_INTEGRITY_H
+#define _LINUX_INTEGRITY_H
+
+#include <linux/fs.h>
+#include <linux/audit.h>
+
+#ifdef CONFIG_INTEGRITY
+void integrity_audit_msg(int audit_msgno, struct inode *inode,
+ const unsigned char *fname, char *op,
+ char *cause, int result);
+
+/*
+ * Integrity API calls:
+ *
+ * @collect_measurement:
+ * Collect template specific measurement data.
+ * @data contains template specific data used for collecting the
+ * measurement.
+ * Return 0 if operation was successful.
+ *
+ * @appraise_measurement:
+ * Appraise the integrity of the template specific measurement data.
+ * @data contains template specific data used for appraising the
+ * measurement.
+ * Return 0 if operation was successful.
+ *
+ * @store_measurement:
+ * Store the template specific data.
+ * @data contains template specific data used for storing the
+ * measurement.
+ *
+ * @must_measure:
+ * Measurement decision based on an integrity policy.
+ * @data contains template specific data used for making policy
+ * decision.
+ * Return 0 if operation was successful.
+ *
+ * @display_template:
+ * Display template specific data.
+ *
+ */
+
+enum integrity_show_type { INTEGRITY_SHOW_BINARY, INTEGRITY_SHOW_ASCII};
+
+struct template_operations {
+ int (*collect_measurement)(void *);
+ int (*appraise_measurement)(void *);
+ void (*store_measurement)(void *);
+ int (*must_measure)(void *);
+ void (*display_template)(struct seq_file *m, void *,
+ enum integrity_show_type);
+};
+extern int integrity_register_template(const char *template_name,
+ const struct template_operations *ops);
+extern int integrity_unregister_template(const char *template_name);
+extern int integrity_find_template(const char *,
+ const struct template_operations **ops);
+
+/*
+ * Integrity hooks:
+ *
+ * @bprm_check_integrity:
+ * This hook mediates the point when a search for a binary handler will
+ * begin. At this point, the OS protects against an executable file,
+ * already open for write, from being executed; and an executable file
+ * already open for execute, from being modified. So we can be certain
+ * that any measurements(collect, appraise, store) done here are of
+ * the file being executed.
+ * @bprm contains the linux_binprm structure.
+ * Return 0 if the hook is successful and permission is granted.
+ *
+ * @inode_alloc_integrity:
+ * Allocate and attach an integrity structure to @inode->i_integrity. The
+ * i_integrity field is initialized to NULL when the inode structure is
+ * allocated.
+ * @inode contains the inode structure.
+ * Return 0 if operation was successful.
+ *
+ * @inode_free_integrity:
+ * @inode contains the inode structure.
+ * Deallocate the inode integrity structure and set @inode->i_integrity to
+ * NULL.
+ *
+ * @inode_permission:
+ * This hook is called by the existing Linux vfs_permission and
+ * file_permission functions, as a file is opened. At this point,
+ * measurements(collect, appraise, store) of files open for read
+ * can be made.
+ * @file contains the file structure of the file being opened(may be NULL).
+ * @path contains the path structure (may be NULL).
+ * @mask contains the permission mask.
+ * Return 0 if the hook is successful and permission is granted.
+ *
+ * @file_free_integrity:
+ * Update the integrity xattr value as necessary.
+ * @file contains the file structure being closed.
+ *
+ * @file_mmap :
+ * Measurements(collect, appraise, store) of files mmaped for EXEC
+ * can be made.
+ * @file contains the file structure of the file to map (may be NULL).
+ * @prot contains the protection that will be applied by the kernel.
+ * Return 0 if the hook is successful and permission is granted.
+ */
+
+enum lim_hooks {INODE_PERMISSION = 1, FILE_MMAP, BPRM_CHECK };
+
+struct integrity_operations {
+ int (*bprm_check_integrity) (struct linux_binprm *bprm);
+ int (*inode_alloc_integrity) (struct inode *inode);
+ void (*inode_free_integrity) (struct inode *inode);
+ int (*inode_permission) (struct file *file, struct path *path,
+ int mask);
+ void (*file_free_integrity) (struct file *file);
+ int (*file_mmap) (struct file *file, unsigned long prot);
+};
+extern int register_integrity(const struct integrity_operations *ops);
+extern int unregister_integrity(const struct integrity_operations *ops);
+
+/* global variables */
+extern const struct integrity_operations *integrity_ops;
+
+
+int integrity_collect_measurement(const char *template_name, void *data);
+int integrity_appraise_measurement(const char *template_name, void *data);
+int integrity_must_measure(const char *template_name, void *data);
+int integrity_store_measurement(const char *template_name, void *data);
+
+int integrity_bprm_check(struct linux_binprm *bprm);
+int integrity_inode_alloc(struct inode *inode);
+void integrity_inode_free(struct inode *inode);
+int integrity_inode_permission(struct file *file, struct path *path,int mask);
+void integrity_file_free(struct file *file);
+int integrity_file_mmap(struct file *file, unsigned long prot);
+#else
+
+static inline int integrity_bprm_check(struct linux_binprm *bprm)
+{
+ return 0;
+}
+
+static inline int integrity_inode_alloc(struct inode *inode)
+{
+ return 0;
+}
+
+static inline void integrity_inode_free(struct inode *inode)
+{
+ return;
+}
+
+static inline int integrity_inode_permission(struct file *file,
+ struct path *path, int mask);
+{
+ return 0;
+}
+
+static inline int integrity_file_permission(struct file *file, int mask)
+{
+ return 0;
+}
+
+static inline void integrity_file_free(struct file *file)
+{
+ return;
+}
+
+static inline int integrity_file_mmap(struct file *file, unsigned long prot)
+{
+ return 0;
+}
+#endif
+#endif
diff --git a/mm/mmap.c b/mm/mmap.c
index 245c3d6..c8b03c1 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -20,6 +20,7 @@
#include <linux/fs.h>
#include <linux/personality.h>
#include <linux/security.h>
+#include <linux/integrity.h>
#include <linux/hugetlb.h>
#include <linux/profile.h>
#include <linux/module.h>
@@ -1046,6 +1047,9 @@ unsigned long do_mmap_pgoff(struct file * file, unsigned long addr,
error = security_file_mmap(file, reqprot, prot, flags, addr, 0);
if (error)
return error;
+ error = integrity_file_mmap(file, prot);
+ if (error)
+ return error;
return mmap_region(file, addr, len, flags, vm_flags, pgoff,
accountable);
diff --git a/security/Kconfig b/security/Kconfig
index 5592939..61453fa 100644
--- a/security/Kconfig
+++ b/security/Kconfig
@@ -4,6 +4,8 @@
menu "Security options"
+source security/integrity/Kconfig
+
config KEYS
bool "Enable access key retention support"
help
diff --git a/security/Makefile b/security/Makefile
index f654260..b8132c9 100644
--- a/security/Makefile
+++ b/security/Makefile
@@ -16,3 +16,7 @@ obj-$(CONFIG_SECURITY_SELINUX) += selinux/built-in.o
obj-$(CONFIG_SECURITY_SMACK) += smack/built-in.o
obj-$(CONFIG_SECURITY_ROOTPLUG) += root_plug.o
obj-$(CONFIG_CGROUP_DEVICE) += device_cgroup.o
+
+# Object integrity file lists
+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..3c29050
--- /dev/null
+++ b/security/integrity/Kconfig
@@ -0,0 +1,24 @@
+#
+# Integrity configuration
+#
+
+menu "Integrity options"
+
+config INTEGRITY
+ bool "Enable different integrity models"
+ help
+ This allows you to choose different integrity modules to be
+ configured into your kernel.
+
+ If you are unsure how to answer this question, answer N.
+
+config INTEGRITY_AUDIT
+ bool "Integrity audit boot parameter"
+ depends on INTEGRITY
+ default y
+ help
+ This option adds a kernel parameter 'integrity_audit', which
+ allows integrity auditing to be disabled at boot. If this
+ option is selected, integrity auditing can be disabled with
+ 'integrity_audit=0' on the kernel command line.
+endmenu
diff --git a/security/integrity/Makefile b/security/integrity/Makefile
new file mode 100644
index 0000000..c9fb803
--- /dev/null
+++ b/security/integrity/Makefile
@@ -0,0 +1,6 @@
+#
+# Makefile for the kernel integrity code
+#
+
+# Object file lists
+obj-$(CONFIG_INTEGRITY) += integrity.o integrity_audit.o
diff --git a/security/integrity/integrity.c b/security/integrity/integrity.c
new file mode 100644
index 0000000..7b6f993
--- /dev/null
+++ b/security/integrity/integrity.c
@@ -0,0 +1,308 @@
+/*
+ * Copyright (C) 2006,2007,2008 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.c
+ * register integrity subsystem
+ * register integrity template
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/integrity.h>
+
+const struct integrity_operations *integrity_ops;
+EXPORT_SYMBOL(integrity_ops);
+
+#define TEMPLATE_NAME_LEN_MAX 12
+struct template_list_entry {
+ struct list_head template;
+ char template_name[TEMPLATE_NAME_LEN_MAX + 1];
+ const struct template_operations *template_ops;
+};
+static LIST_HEAD(integrity_templates);
+static DEFINE_MUTEX(integrity_templates_mutex);
+
+/**
+ * register_integrity - registers an integrity framework with the kernel
+ * @ops: a pointer to the struct security_options that is to be registered
+ *
+ * Perhaps in the future integrity module stacking will be necessary, but
+ * for the time being, this function permits only one integrity module to
+ * register itself with the kernel integrity subsystem.
+ *
+ * If another integrity module is already registered, an error code is
+ * returned. On success 0 is returned.
+ */
+int register_integrity(const struct integrity_operations *ops)
+{
+ if (integrity_ops != NULL)
+ return -EAGAIN;
+ integrity_ops = ops;
+ return 0;
+}
+
+EXPORT_SYMBOL_GPL(register_integrity);
+
+/**
+ * unregister_integrity - unregisters an integrity framework from the kernel
+ * @ops: a pointer to the struct security_options that is to be registered
+ *
+ * Returns 0 on success, -EINVAL on failure.
+ */
+int unregister_integrity(const struct integrity_operations *ops)
+{
+ if (ops != integrity_ops)
+ return -EINVAL;
+
+ integrity_ops = NULL;
+ return 0;
+}
+
+EXPORT_SYMBOL_GPL(unregister_integrity);
+
+/**
+ * integrity_register_template - registers an integrity template with the kernel
+ * @template_name: a pointer to a string containing the template name.
+ * @template_ops: a pointer to the template functions
+ *
+ * Register a set of functions to collect, appraise, store, and display
+ * a template measurement, and a means to decide whether to do them.
+ * Unlike integrity modules, any number of templates may be registered.
+ *
+ * Returns 0 on success, an error code on failure.
+ */
+int integrity_register_template(const char *template_name,
+ const struct template_operations *template_ops)
+{
+ int template_len;
+ struct template_list_entry *entry;
+
+ entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+ if (!entry)
+ return -ENOMEM;
+ INIT_LIST_HEAD(&entry->template);
+
+ template_len = strlen(template_name);
+ if (template_len > TEMPLATE_NAME_LEN_MAX)
+ return -EINVAL;
+ strcpy(entry->template_name, template_name);
+ entry->template_ops = template_ops;
+
+ mutex_lock(&integrity_templates_mutex);
+ list_add_rcu(&entry->template, &integrity_templates);
+ mutex_unlock(&integrity_templates_mutex);
+ synchronize_rcu();
+
+ return 0;
+}
+
+EXPORT_SYMBOL_GPL(integrity_register_template);
+
+/**
+ * integrity_unregister_template: unregister a template
+ * @template_name: a pointer to a string containing the template name.
+ *
+ * Returns 0 on success, -EINVAL on failure.
+ */
+int integrity_unregister_template(const char *template_name)
+{
+ struct template_list_entry *entry;
+
+ mutex_lock(&integrity_templates_mutex);
+ list_for_each_entry(entry, &integrity_templates, template) {
+ if (strncmp(entry->template_name, template_name,
+ strlen(entry->template_name)) == 0) {
+ list_del_rcu(&entry->template);
+ mutex_unlock(&integrity_templates_mutex);
+ synchronize_rcu();
+ kfree(entry);
+ return 0;
+ }
+ }
+ mutex_unlock(&integrity_templates_mutex);
+ return -EINVAL;
+}
+
+EXPORT_SYMBOL_GPL(integrity_unregister_template);
+
+/**
+ * integrity_find_template - search the integrity_templates list
+ * @template_name: a pointer to a string containing the template name.
+ * @template_ops: a pointer to the template functions
+ *
+ * Called with an rcu_read_lock
+ * Returns 0 on success, -EINVAL on failure.
+ */
+int integrity_find_template(const char *template_name,
+ const struct template_operations **template_ops)
+{
+ struct template_list_entry *entry;
+
+ list_for_each_entry_rcu(entry, &integrity_templates, template) {
+ if (strncmp(entry->template_name, template_name,
+ strlen(entry->template_name)) == 0) {
+ *template_ops = entry->template_ops;
+ return 0;
+ }
+ }
+ return -EINVAL;
+}
+
+EXPORT_SYMBOL_GPL(integrity_find_template);
+
+/* Start of the integrity API calls */
+
+/**
+ * integrity_collect_measurement - collect template specific measurement
+ * @template_name: a pointer to a string containing the template name.
+ * @data: pointer to template specific data
+ *
+ * Returns 0 on success, an error code on failure.
+ */
+int integrity_collect_measurement(const char *template_name, void *data)
+{
+ const struct template_operations *template_ops;
+ int rc;
+
+ rcu_read_lock();
+ rc = integrity_find_template(template_name, &template_ops);
+ if (rc == 0)
+ rc = template_ops->collect_measurement(data);
+ rcu_read_unlock();
+ return rc;
+}
+
+EXPORT_SYMBOL_GPL(integrity_collect_measurement);
+
+/**
+ * integrity_appraise_measurement - appraise template specific measurement
+ * @template_name: a pointer to a string containing the template name.
+ * @data: pointer to template specific data
+ *
+ * Returns 0 on success, an error code on failure
+ */
+int integrity_appraise_measurement(const char *template_name, void *data)
+{
+ const struct template_operations *template_ops;
+ int rc;
+
+ rcu_read_lock();
+ rc = integrity_find_template(template_name, &template_ops);
+ if (rc == 0)
+ rc = template_ops->appraise_measurement(data);
+ rcu_read_unlock();
+ return rc;
+}
+
+EXPORT_SYMBOL_GPL(integrity_appraise_measurement);
+
+/**
+ * integrity_store_measurement - store template specific measurement
+ * @template_name: a pointer to a string containing the template name.
+ * @data: pointer to template specific data
+ *
+ * Store template specific integrity measurement.
+ */
+int integrity_store_measurement(const char *template_name, void *data)
+{
+ const struct template_operations *template_ops;
+ int rc;
+
+ rcu_read_lock();
+ rc = integrity_find_template(template_name, &template_ops);
+ if (rc == 0)
+ template_ops->store_measurement(data);
+ rcu_read_unlock();
+ return rc;
+}
+
+EXPORT_SYMBOL_GPL(integrity_store_measurement);
+
+/**
+ * integrity_must_measure - measure decision based on template policy
+ * @template_name: a pointer to a string containing the template name.
+ * @data: pointer to template specific data
+ *
+ * Returns 0 on success, an error code on failure.
+ */
+int integrity_must_measure(const char *template_name, void *data)
+{
+ const struct template_operations *template_ops;
+ int rc;
+
+ rcu_read_lock();
+ rc = integrity_find_template(template_name, &template_ops);
+ if (rc == 0)
+ rc = template_ops->must_measure(data);
+ rcu_read_unlock();
+ return rc;
+}
+
+EXPORT_SYMBOL_GPL(integrity_must_measure);
+
+/* Start of the integrity Hooks */
+
+/* Hook used to measure executable file integrity. */
+int integrity_bprm_check(struct linux_binprm *bprm)
+{
+ int rc = 0;
+
+ if (integrity_ops && integrity_ops->bprm_check_integrity)
+ rc = integrity_ops->bprm_check_integrity(bprm);
+ return rc;
+}
+
+/* Allocate, attach and initialize an inode's i_integrity,
+ * if INTEGRITY is configured.
+ */
+int integrity_inode_alloc(struct inode *inode)
+{
+ int rc = 0;
+
+ if (integrity_ops && integrity_ops->inode_alloc_integrity)
+ rc = integrity_ops->inode_alloc_integrity(inode);
+ return rc;
+}
+
+/* Hook used to free an inode's i_integrity structure. */
+void integrity_inode_free(struct inode *inode)
+{
+ if (integrity_ops && integrity_ops->inode_free_integrity)
+ integrity_ops->inode_free_integrity(inode);
+}
+
+/* Hook used to measure a file's integrity. */
+int integrity_inode_permission(struct file *file, struct path *path, int mask)
+{
+ int rc = 0;
+
+ if (integrity_ops && integrity_ops->inode_permission)
+ rc = integrity_ops->inode_permission(file, path, mask);
+ return rc;
+}
+
+/* Hook used to update i_integrity data and integrity xattr values
+ * as necessary.
+ */
+void integrity_file_free(struct file *file)
+{
+ if (integrity_ops && integrity_ops->file_free_integrity)
+ integrity_ops->file_free_integrity(file);
+}
+
+/* Hook used to measure integrity of an mmapped file */
+int integrity_file_mmap(struct file *file, unsigned long prot)
+{
+ int rc = 0;
+
+ if (integrity_ops && integrity_ops->file_mmap)
+ rc = integrity_ops->file_mmap(file, prot);
+ return rc;
+}
diff --git a/security/integrity/integrity_audit.c b/security/integrity/integrity_audit.c
new file mode 100644
index 0000000..2f8b835
--- /dev/null
+++ b/security/integrity/integrity_audit.c
@@ -0,0 +1,79 @@
+/*
+ * 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/audit.h>
+#include <linux/fs.h>
+#include <linux/integrity.h>
+
+static int integrity_audit = 1;
+
+#ifdef CONFIG_INTEGRITY_AUDIT
+static int __init integrity_audit_setup(char *str)
+{
+ ulong audit;
+ int rc;
+ char *op;
+
+ rc = strict_strtoul(str, 10, &audit);
+ if (rc < 0 || audit > 1)
+ printk(KERN_INFO "integrity: invalid integrity_audit value\n");
+ else
+ integrity_audit = audit;
+
+ op = integrity_audit ? "integrity_audit_enabled" :
+ "integrity_audit_not_enabled";
+ integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL, NULL, NULL, op, 0);
+ return 1;
+}
+
+__setup("integrity_audit=", integrity_audit_setup);
+#endif
+
+void integrity_audit_msg(int audit_msgno, struct inode *inode,
+ const unsigned char *fname, char *op,
+ char *cause, int result)
+{
+ struct audit_buffer *ab;
+
+ if (!integrity_audit && result == 1)
+ return;
+
+ ab = audit_log_start(current->audit_context, GFP_KERNEL, audit_msgno);
+ audit_log_format(ab, "integrity: pid=%d uid=%u auid=%u",
+ current->pid, current->uid,
+ audit_get_loginuid(current));
+ audit_log_task_context(ab);
+ switch (audit_msgno) {
+ case AUDIT_INTEGRITY_DATA:
+ case AUDIT_INTEGRITY_METADATA:
+ case AUDIT_INTEGRITY_PCR:
+ audit_log_format(ab, " op=%s cause=%s", op, cause);
+ break;
+ case AUDIT_INTEGRITY_HASH:
+ audit_log_format(ab, " op=%s hash=%s", op, cause);
+ break;
+ case AUDIT_INTEGRITY_STATUS:
+ default:
+ audit_log_format(ab, " op=%s", op);
+ }
+ audit_log_format(ab, " comm=");
+ audit_log_untrustedstring(ab, current->comm);
+ if (fname) {
+ audit_log_format(ab, " name=");
+ audit_log_untrustedstring(ab, fname);
+ }
+ if (inode)
+ audit_log_format(ab, " dev=%s ino=%lu",
+ inode->i_sb->s_id, inode->i_ino);
+ audit_log_format(ab, " res=%d", result);
+ audit_log_end(ab);
+}
--
1.5.5.1
^ permalink raw reply related [flat|nested] 35+ messages in thread* [PATCH 4/4] integrity: IMA as an integrity service provider
2008-10-07 18:00 [PATCH 0/4] integrity Mimi Zohar
` (2 preceding siblings ...)
2008-10-07 18:00 ` [PATCH 3/4] integrity: Linux Integrity Module(LIM) Mimi Zohar
@ 2008-10-07 18:00 ` Mimi Zohar
2008-10-08 4:56 ` [PATCH 0/4] integrity James Morris
4 siblings, 0 replies; 35+ messages in thread
From: Mimi Zohar @ 2008-10-07 18:00 UTC (permalink / raw)
To: linux-kernel
Cc: Mimi Zohar, Andrew Morton, James Morris, Christoph Hellwig,
Al Viro, David Safford, Serge Hallyn, Mimi Zohar
This is a re-release of Integrity Measurement Architecture(IMA) as an
independent Linunx Integrity Module(LIM) service provider.
This version addresses the merge issues resulting from the removal of
the nameidata parameter to inode_permission().
- The parameter changes to integrity_inode_permission() are reflected
here in this patch.
As a LIM integrity provider, IMA implements the new LIM must_measure(),
collect_measurement(), store_measurement(), and display_template() API
calls. The store_measurement() call supports two types of data, IMA
(i.e. file data) and generic template data.
IMA provides hardware (TPM) based measurement and attestation for both
files and other types of template measurements. As the Trusted Computing
(TPM) model requires, IMA measures all files before they are accessed
in any way (on the bprm_check_integrity, file_mmap and inode_permission
hooks), and commits the measurements to the TPM. In addition, IMA
maintains a list of these hash values, which can be used to validate
the aggregate PCR value. The TPM can sign these measurements, and thus
the system can prove to itself and to a third party these measurements
in a way that cannot be circumvented by malicious or compromised software.
When store_measurement() is called for the IMA type of data, the file
measurement and the file name hint are used to form an IMA template.
IMA then calculates the IMA template measurement(hash) and submits it
to the TPM chip for inclusion in one of the chip's Platform Configuration
Registers (PCR).
When store_measurement() is called for generic template data, IMA
calculates the measurement(hash) of the template data, and submits
the template measurement to the TPM chip for inclusion in one of the
chip's Platform Configuration Registers(PCR).
In order to view the contents of template data through securityfs, the
template_display() function must be defined in the registered
template_operations. In the case of the IMA template, the list of
file names and files hashes submitted can be viewed through securityfs.
As mentioned above, IMA maintains a list of hash values of executables
and other sensitive system files loaded into the run-time of the system.
Our work has shown that requests for integrity appraisal and measurement
need to be based on knowledge of the filesystem, requiring the system
to either be labeled with integrity data or depend on the existent LSM
security labels. The previous set of integrity patches modified the LSM
modules to be integrity context aware, meaning that the LSM modules made
integrity data/metadata appraisal and measurement API calls based on
an understanding of the LSM security labels. Both of the LSM maintainers
felt that the changes were too intrusive and that integrity enforcement
should be made by the integrity provider, not the LSM module.
To address these concerns, Stephen Smalley suggested using the
security_audit_rule_match(), renamed to security_filter_rule_match(), to
define LSM specific integrity measurement policy rules, in lieu of
modifying the LSM modules. In the current set of patches, the integrity
API calls can be made either by IMA, based on an LSM specific integrity
policy, or by an integrity context aware LSM.
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
---
diff --git a/Documentation/ABI/testing/ima_policy b/Documentation/ABI/testing/ima_policy
new file mode 100644
index 0000000..c9ab220
--- /dev/null
+++ b/Documentation/ABI/testing/ima_policy
@@ -0,0 +1,60 @@
+What: security/ima/policy
+Date: May 2008
+Contact: Mimi Zohar <zohar@us.ibm.com>
+Description:
+ The Trusted Computing Group(TCG) runtime Integrity
+ Measurement Architecture(IMA) maintains a list of hash
+ values of executables and other sensitive system files
+ loaded into the run-time of this system. At runtime,
+ the policy can be constrained based on LSM specific data.
+ Policies are loaded into security/ima/policy by opening
+ the file, writing the rules one at a time and then
+ closing the file. The new policy takes effect after
+ the security/ima/policy is closed.
+
+ rule format: action [condition ...]
+
+ action: measure | dont_measure
+ condition:= base | lsm
+ base: [[func=] [mask=] [fsmagic=] [uid=]]
+ lsm: [[subj_user=] [subj_role=] [subj_type=]
+ [obj_user=] [obj_role=] [obj_type=]]
+
+ base: func:= [BPRM_CHECK][FILE_MMAP][INODE_PERMISSION]
+ mask:= [MAY_READ] [MAY_WRITE] [MAY_APPEND] [MAY_EXEC]
+ fsmagic:= hex value
+ uid:= decimal value
+ lsm: are LSM specific
+
+ default policy:
+ # PROC_SUPER_MAGIC
+ dont_measure fsmagic=0x9fa0
+ # SYSFS_MAGIC
+ dont_measure fsmagic=0x62656572
+ # DEBUGFS_MAGIC
+ dont_measure fsmagic=0x64626720
+ # TMPFS_MAGIC
+ dont_measure fsmagic=0x01021994
+ # SECURITYFS_MAGIC
+ dont_measure fsmagic=0x73636673
+ # SELINUX_MAGIC
+ dont_measure fsmagic=0xF97CFF8C
+
+ measure func=BPRM_CHECK
+ measure func=FILE_MMAP mask=MAY_EXEC
+ measure func=INODE_PERM mask=MAY_READ uid=0
+
+ The default policy measures all executables in bprm_check,
+ all files mmapped executable in file_mmap, and all files
+ open for read by root in inode_permission.
+
+ Examples of LSM specific definitions:
+
+ SELinux:
+ dont_measure obj_type=var_log_t
+ dont_measure obj_type=auditd_log_t
+ measure subj_user=system_u func=INODE_PERM mask=MAY_READ
+ measure subj_role=system_r func=INODE_PERM mask=MAY_READ
+
+ Smack:
+ measure subj_user=_ func=INODE_PERM mask=MAY_READ
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 8a30e55..b6d7946 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -44,6 +44,7 @@ parameter is applicable:
FB The frame buffer device is enabled.
HW Appropriate hardware is enabled.
IA-64 IA-64 architecture is enabled.
+ IMA Integrity measurement architecture is enabled.
INTEGRITY Integrity support is enabled.
IOSCHED More than one I/O scheduler is enabled.
IP_PNP IP DHCP, BOOTP, or RARP is enabled.
@@ -862,6 +863,10 @@ and is between 256 and 4096 characters. It is defined in the file
ihash_entries= [KNL]
Set number of hash buckets for inode cache.
+ ima_hash= [IMA] runtime ability to define hash crypto algorithm.
+ Format: { "MD5" | "SHA1" }
+ Default is "SHA1".
+
in2000= [HW,SCSI]
See header of drivers/scsi/in2000.c.
diff --git a/include/linux/ima.h b/include/linux/ima.h
new file mode 100644
index 0000000..c777b71
--- /dev/null
+++ b/include/linux/ima.h
@@ -0,0 +1,46 @@
+/*
+ * ima.h
+ *
+ * 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.
+ */
+
+#ifndef _LINUX_IMA_H
+#define _LINUX_IMA_H
+
+/* IMA LIM Data */
+enum ima_type { IMA_DATA, IMA_METADATA, IMA_TEMPLATE };
+
+struct ima_args_data {
+ const char *filename;
+ struct file *file;
+ struct path *path;
+ struct dentry *dentry;
+ struct inode *inode;
+ enum lim_hooks function;
+ u32 osid;
+ int mask;
+};
+
+struct ima_store_data {
+ char *name;
+ int len;
+ char *data;
+ int violation;
+};
+
+struct ima_data {
+ enum ima_type type;
+ union {
+ struct ima_args_data args;
+ struct ima_store_data template;
+ } data;
+};
+
+void ima_fixup_argsdata(struct ima_args_data *data, struct file *file,
+ struct path *path, int mask, int function);
+#endif
diff --git a/security/integrity/Kconfig b/security/integrity/Kconfig
index 3c29050..28b44e3 100644
--- a/security/integrity/Kconfig
+++ b/security/integrity/Kconfig
@@ -2,8 +2,6 @@
# Integrity configuration
#
-menu "Integrity options"
-
config INTEGRITY
bool "Enable different integrity models"
help
@@ -21,4 +19,5 @@ config INTEGRITY_AUDIT
allows integrity auditing to be disabled at boot. If this
option is selected, integrity auditing can be disabled with
'integrity_audit=0' on the kernel command line.
-endmenu
+
+source security/integrity/ima/Kconfig
diff --git a/security/integrity/Makefile b/security/integrity/Makefile
index c9fb803..8eb7a4a 100644
--- a/security/integrity/Makefile
+++ b/security/integrity/Makefile
@@ -4,3 +4,5 @@
# Object file lists
obj-$(CONFIG_INTEGRITY) += integrity.o integrity_audit.o
+
+obj-$(CONFIG_IMA) += ima/
diff --git a/security/integrity/ima/Kconfig b/security/integrity/ima/Kconfig
new file mode 100644
index 0000000..ca25b0b
--- /dev/null
+++ b/security/integrity/ima/Kconfig
@@ -0,0 +1,48 @@
+#
+# IBM Integrity Measurement Architecture
+#
+
+config IMA
+ bool "Integrity Measurement Architecture(IMA)"
+ depends on INTEGRITY
+ depends on ACPI
+ select CRYPTO
+ select CRYPTO_HMAC
+ select CRYPTO_MD5
+ select CRYPTO_SHA1
+ select TCG_TPM
+ select TCG_TIS
+ help
+ The Trusted Computing Group(TCG) runtime Integrity
+ Measurement Architecture(IMA) maintains a list of hash
+ values of executables and other sensitive system files
+ loaded into the run-time of this system. If your system
+ has a TPM chip, then IMA also maintains an aggregate
+ integrity value over this list inside the TPM hardware.
+ These measurements and the aggregate (signed inside the
+ TPM) can be retrieved and presented to remote parties to
+ establish system properties. If unsure, say N.
+
+config IMA_MEASURE_PCR_IDX
+ int "PCR for Aggregate (8 <= Index <= 14)"
+ depends on IMA
+ range 8 14
+ default 10
+ help
+ IMA_MEASURE_PCR_IDX determines the TPM PCR register index
+ that IMA uses to maintain the integrity aggregate of the
+ measurement list. If unsure, use the default 10.
+
+config IMA_BASE_HOOKS
+ bool "IMA base hooks"
+ depends on IMA
+ default n
+ help
+ Enable this option to allow the LSM module to enforce integrity.
+
+config IMA_LSM_RULES
+ bool "Enable LSM measurement policy rules"
+ depends on IMA && (SECURITY_SELINUX || SECURITY_SMACK)
+ default y
+ help
+ Disabling this option will not enforce LSM based policy rules.
diff --git a/security/integrity/ima/Makefile b/security/integrity/ima/Makefile
new file mode 100644
index 0000000..f3aced4
--- /dev/null
+++ b/security/integrity/ima/Makefile
@@ -0,0 +1,9 @@
+#
+# Makefile for building Trusted Computing Group's(TCG) runtime Integrity
+# Measurement Architecture(IMA).
+#
+
+obj-$(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
diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
new file mode 100644
index 0000000..aed5f9f
--- /dev/null
+++ b/security/integrity/ima/ima.h
@@ -0,0 +1,170 @@
+/*
+ * 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 ima definitions
+ */
+
+#ifndef __LINUX_IMA_H
+#define __LINUX_IMA_H
+
+#include <linux/types.h>
+#include <linux/crypto.h>
+#include <linux/security.h>
+#include <linux/integrity.h>
+#include <linux/hash.h>
+#include <linux/tpm.h>
+
+#define ima_printk(level, format, arg...) \
+ printk(level "ima (%s): " format, __func__, ## arg)
+
+#define ima_error(format, arg...) \
+ ima_printk(KERN_ERR, format, ## arg)
+
+#define ima_info(format, arg...) \
+ ima_printk(KERN_INFO, format, ## arg)
+
+/* digest size for IMA, fits SHA1 or MD5 */
+#define IMA_DIGEST_SIZE 20
+#define IMA_EVENT_NAME_LEN_MAX 255
+
+#define IMA_HASH_BITS 9
+#define IMA_MEASURE_HTABLE_SIZE (1 << IMA_HASH_BITS)
+
+/* set during initialization */
+extern int ima_used_chip;
+extern char *ima_hash;
+
+struct ima_measure_entry {
+ u8 digest[IMA_DIGEST_SIZE]; /* sha1 or md5 measurement hash */
+ char template_name[IMA_EVENT_NAME_LEN_MAX + 1]; /* name + \0 */
+ int template_len;
+ char *template;
+};
+
+struct ima_queue_entry {
+ struct hlist_node hnext; /* place in hash collision list */
+ struct list_head later; /* place in ima_measurements list */
+ struct ima_measure_entry *entry;
+};
+extern struct list_head ima_measurements; /* list of all measurements */
+
+/* declarations */
+extern int ima_template_mode;
+extern const struct template_operations ima_template_ops;
+
+/* Internal IMA function definitions */
+int ima_init(void);
+void ima_cleanup(void);
+int ima_fs_init(void);
+void ima_fs_cleanup(void);
+void ima_create_htable(void);
+int ima_add_measure_entry(struct ima_measure_entry *entry, int violation);
+struct ima_queue_entry *ima_lookup_digest_entry(u8 *digest);
+int ima_calc_hash(struct file *file, struct path *path, char *digest);
+int ima_calc_template_hash(int template_len, char *template, char *digest);
+void ima_add_violation(struct inode *inode, const unsigned char *fname,
+ char *op, char *cause);
+
+enum ima_action {DONT_MEASURE, MEASURE};
+int ima_match_policy(struct inode *inode, enum lim_hooks func, int mask);
+int ima_add_rule(int, char *subj_user, char *subj_role, char *subj_type,
+ char *obj_user, char *obj_role, char *obj_type,
+ char *func, char *mask, char *fsmagic, char *uid);
+void ima_init_policy(void);
+void ima_update_policy(void);
+
+
+/* LIM API function definitions */
+int ima_must_measure(void *d);
+int ima_collect_measurement(void *d);
+int ima_appraise_measurement(void *d);
+void ima_store_measurement(void *d);
+void ima_template_show(struct seq_file *m, void *e,
+ enum integrity_show_type show);
+
+
+/*
+ * 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;
+ unsigned int max_htable_size;
+ struct hlist_head queue[IMA_MEASURE_HTABLE_SIZE];
+ atomic_t queue_len[IMA_MEASURE_HTABLE_SIZE];
+};
+extern struct ima_h_table ima_htable;
+
+static inline unsigned long IMA_HASH_KEY(u8 *digest)
+{
+ return(hash_ptr(digest, IMA_HASH_BITS));
+}
+
+/* TPM "Glue" definitions */
+
+#define IMA_TPM ((((u32)TPM_ANY_TYPE)<<16) | (u32)TPM_ANY_NUM)
+static inline void ima_extend(const u8 *hash)
+{
+ if (!ima_used_chip)
+ return;
+
+ if (tpm_pcr_extend(IMA_TPM, CONFIG_IMA_MEASURE_PCR_IDX, hash) != 0)
+ ima_error("Error Communicating to TPM chip\n");
+}
+
+static inline void ima_pcrread(int idx, u8 *pcr, int pcr_size)
+{
+ if (!ima_used_chip)
+ return;
+
+ if (tpm_pcr_read(IMA_TPM, idx, pcr) != 0)
+ ima_error("Error Communicating to TPM chip\n");
+}
+
+struct ima_inode_measure_entry {
+ u8 digest[IMA_DIGEST_SIZE]; /* sha1/md5 measurement hash */
+ char file_name[IMA_EVENT_NAME_LEN_MAX + 1]; /* name + \0 */
+};
+
+/* inode integrity data */
+struct ima_iint_cache {
+ u64 version;
+ int measured;
+ u8 hmac[IMA_DIGEST_SIZE];
+ u8 digest[IMA_DIGEST_SIZE];
+ struct mutex mutex;
+};
+
+/* 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
+#endif
diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c
new file mode 100644
index 0000000..c6d93bc
--- /dev/null
+++ b/security/integrity/ima/ima_api.c
@@ -0,0 +1,348 @@
+/*
+ * 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 the LIM API
+ */
+#include <linux/module.h>
+#include <linux/integrity.h>
+#include <linux/magic.h>
+#include <linux/writeback.h>
+#include <linux/string.h>
+#include <linux/list.h>
+#include <linux/audit.h>
+#include <linux/ima.h>
+
+#include "ima.h"
+
+const struct template_operations ima_template_ops = {
+ .must_measure = ima_must_measure,
+ .collect_measurement = ima_collect_measurement,
+ .store_measurement = ima_store_measurement,
+ .display_template = ima_template_show
+};
+
+/**
+ * mode_setup - for compatability with non-template IMA versions
+ * @str: is pointer to a string
+ */
+int ima_template_mode = 1;
+static int __init mode_setup(char *str)
+{
+ if (strncmp(str, "ima", 3) == 0)
+ ima_template_mode = 0;
+ if (strncmp(str, "template", 7) == 0)
+ ima_template_mode = 1;
+ ima_info("template_mode %s \n",
+ ima_template_mode ? "template" : "ima");
+ return 1;
+}
+
+__setup("ima_mode=", mode_setup);
+
+/**
+ * ima_digest_cpy - copy the hash in the IMA template structure to a digest
+ * @template_name: string containing the name of the template (i.e. "ima")
+ * @template: pointer to template structure
+ * @digest: pointer to the digest
+ *
+ * Returns 0 on success, error code otherwise
+ */
+static int ima_digest_cpy(char *template_name, void *template, u8 *digest)
+{
+ int rc, result = 0;
+ struct ima_inode_measure_entry *inode_template =
+ (struct ima_inode_measure_entry *)template;
+
+ rc = strcmp(template_name, "ima");
+ if (rc == 0)
+ memcpy(digest, inode_template->digest,
+ sizeof inode_template->digest);
+ else
+ result = -ENODATA;
+ return result;
+}
+
+/**
+ * ima_store_template_measure - collect and protect template measurements
+ * @template_name: string containing the name of the template (i.e. "ima")
+ * @template_len: length of the template data
+ * @template: actual template data
+ * @violation: invalidate pcr measurement indication
+ * @audit_cause: string containing the audit failure cause
+ *
+ * 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
+ */
+static int ima_store_template_measure(char *template_name, int template_len,
+ char *template, int violation,
+ char **audit_cause)
+{
+ struct ima_measure_entry *entry;
+ u8 digest[IMA_DIGEST_SIZE];
+ struct ima_queue_entry *qe;
+ int count, result = 0;
+
+ memset(digest, 0, IMA_DIGEST_SIZE);
+ if (!violation) {
+ int rc = -ENODATA;
+
+ if (!ima_template_mode)
+ rc = ima_digest_cpy(template_name, template, digest);
+ if (rc < 0)
+ result = ima_calc_template_hash(template_len, template,
+ digest);
+
+ /* hash exists already? */
+ qe = ima_lookup_digest_entry(digest);
+ if (qe) {
+ *audit_cause = "hash_exists";
+ result = -EEXIST;
+ goto out;
+ }
+ }
+
+ /* create new entry and add to measurement list */
+ entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+ if (!entry) {
+ *audit_cause = "ENOMEM";
+ result = -ENOMEM;
+ goto out;
+ }
+
+ entry->template = kzalloc(template_len, GFP_KERNEL);
+ if (!entry->template) {
+ *audit_cause = "ENOMEM";
+ result = -ENOMEM;
+ goto out;
+ }
+ if (!template_name) {
+ *audit_cause = "null_template_name";
+ count = 1;
+ } else {
+ count = strlen(template_name);
+ if (count > IMA_EVENT_NAME_LEN_MAX)
+ count = IMA_EVENT_NAME_LEN_MAX;
+ memcpy(entry->template_name, template_name, count);
+ }
+ entry->template_name[count] = '\0';
+ entry->template_len = template_len;
+ memcpy(entry->template, template, template_len);
+ memcpy(entry->digest, digest, IMA_DIGEST_SIZE);
+
+ result = ima_add_measure_entry(entry, violation);
+ if (result < 0)
+ kfree(entry);
+out:
+ return result;
+}
+
+/**
+ * ima_store_inode_measure - create and store an inode template measurement
+ * @name: ascii file name associated with the measurement hash
+ * @hash_len: length of hash value in bytes (16 for MD5, 20 for SHA1)
+ * @hash: actual hash value pre-calculated
+ *
+ * Returns 0 on success, error code otherwise
+ */
+static int ima_store_inode_measure(struct inode *inode,
+ const unsigned char *name,
+ int hash_len, char *hash, int violation)
+{
+ struct ima_inode_measure_entry measure_entry, *entry = &measure_entry;
+ int result;
+ int namelen;
+ char *op = "add_measure";
+ char *cause = " ";
+
+ memset(entry, 0, sizeof *entry);
+ if (!violation)
+ memcpy(entry->digest, hash, hash_len > IMA_DIGEST_SIZE ?
+ IMA_DIGEST_SIZE : hash_len);
+ if (name) {
+ namelen = strlen(name);
+ memcpy(entry->file_name, name, namelen > IMA_EVENT_NAME_LEN_MAX
+ ? IMA_EVENT_NAME_LEN_MAX : namelen);
+ entry->file_name[namelen] = '\0';
+ }
+ result = ima_store_template_measure("ima", sizeof *entry, (char *)entry,
+ violation, &cause);
+ if (result < 0)
+ integrity_audit_msg(AUDIT_INTEGRITY_PCR, inode,
+ name, op, cause, result);
+ return result;
+}
+
+/**
+ * ima_add_violation - add violation to measurement list.
+ * @inode: inode associated with the violation
+ * @fname: name associated with the inode
+ * @op: string pointer to audit operation (i.e. "invalid_pcr", "add_measure")
+ * @cause: string pointer to reason for violation (i.e. "ToMToU")
+ *
+ * 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 inode *inode, const unsigned char *fname,
+ char *op, char *cause)
+{
+ int result;
+
+ /* can overflow, only indicator */
+ atomic_long_inc(&ima_htable.violations);
+
+ result = ima_store_inode_measure(inode, fname, 0, NULL, 1);
+ integrity_audit_msg(AUDIT_INTEGRITY_PCR, inode, fname, op,
+ cause, result);
+}
+
+/**
+ * skip_measurement - measure only regular files, skip everything else.
+ * @inode: inode being measured
+ * @mask: contains the permission mask
+ *
+ * Quick sanity check to make sure that only regular files opened
+ * for read-only or execute are measured.
+ *
+ * Return 1 to skip measure, 0 to measure
+ */
+static int skip_measurement(struct inode *inode, int mask)
+{
+ if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
+ return 1; /* can't measure */
+
+ if (special_file(inode->i_mode) || S_ISLNK(inode->i_mode))
+ return 1; /* don't measure */
+
+ if (S_ISREG(inode->i_mode))
+ return 0; /* measure */
+ return 1; /* don't measure */
+}
+
+/**
+ * ima_must_measure - measure decision based on policy.
+ * @template_data: pointer to struct ima_data containing ima_args_data
+ *
+ * The policy is defined in terms of keypairs:
+ * subj=, obj=, type=, func=, mask=, fsmagic=
+ * subj,obj, and type: are LSM specific.
+ * func: INODE_PERMISSION | BPRM_CHECK | FILE_MMAP
+ * mask: contains the permission mask
+ * fsmagic: hex value
+ *
+ * Return 0 to measure. For matching a DONT_MEASURE policy, no policy,
+ * or other error, return an error code.
+*/
+int ima_must_measure(void *template_data)
+{
+ struct ima_data *idata = (struct ima_data *)template_data;
+ struct ima_args_data *data = &idata->data.args;
+ int rc;
+
+ if ((data->mask & MAY_WRITE) || (data->mask & MAY_APPEND))
+ return -EPERM;
+
+ if (skip_measurement(data->inode, data->mask))
+ return -EPERM;
+
+ rc = ima_match_policy(data->inode, data->function, data->mask);
+ if (rc)
+ return 0;
+ return -EACCES;
+}
+
+/**
+ * ima_collect_measurement - collect file measurements and store in the inode
+ * @template_data: pointer to struct ima_data containing ima_args_data
+ *
+ * Return 0 on success, error code otherwise
+ */
+int ima_collect_measurement(void *template_data)
+{
+ struct ima_iint_cache *iint;
+ struct ima_data *idata = (struct ima_data *)template_data;
+ struct ima_args_data *data = &idata->data.args;
+ struct dentry *dentry = data->dentry;
+ struct inode *inode = data->inode;
+ int result = 0;
+
+ if (idata->type != IMA_DATA)
+ return -EPERM;
+
+ if (!inode || !dentry)
+ return -EINVAL;
+
+ iint = inode->i_integrity;
+ mutex_lock(&iint->mutex);
+ if (!iint->measured) {
+ memset(iint->digest, 0, IMA_DIGEST_SIZE);
+ result = ima_calc_hash(data->file, data->path, iint->digest);
+ } else
+ result = -EEXIST;
+ mutex_unlock(&iint->mutex);
+ return result;
+}
+
+/**
+ * ima_store_measurement - store file and template measurements
+ * @template_data: pointer to struct ima_data containing ima_args_data,
+ * used to create an IMA template, or a template.
+ *
+ * For file measurements, first create an IMA template and then store it.
+ * For all other types of template measurements, just store it.
+ */
+void ima_store_measurement(void *template_data)
+{
+ struct ima_data *idata = (struct ima_data *)template_data;
+ int result;
+ char *op = "add_template_measure";
+ char *cause = "";
+
+ if (idata->type == IMA_DATA) {
+ struct ima_args_data *data = &idata->data.args;
+ struct ima_iint_cache *iint;
+
+ iint = data->inode->i_integrity;
+ mutex_lock(&iint->mutex);
+ if (iint->measured) {
+ mutex_unlock(&iint->mutex);
+ return;
+ }
+ result = ima_store_inode_measure(data->inode, data->filename,
+ IMA_DIGEST_SIZE, iint->digest,
+ 0);
+ if (!result || result == -EEXIST) {
+ iint->measured = 1;
+ iint->version = data->inode->i_version;
+ }
+ mutex_unlock(&iint->mutex);
+ } else if (idata->type == IMA_TEMPLATE) {
+ struct ima_store_data *template = (struct ima_store_data *)
+ &idata->data.template;
+
+ result = ima_store_template_measure(template->name,
+ template->len,
+ template->data, 0, &cause);
+ if (result < 0)
+ integrity_audit_msg(AUDIT_INTEGRITY_PCR, NULL,
+ template->name, op, cause, result);
+ }
+}
diff --git a/security/integrity/ima/ima_crypto.c b/security/integrity/ima/ima_crypto.c
new file mode 100644
index 0000000..c75b22e
--- /dev/null
+++ b/security/integrity/ima/ima_crypto.c
@@ -0,0 +1,153 @@
+/*
+ * 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
+ * Calculate a file's or a template's hash.
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/file.h>
+#include <linux/fs.h>
+#include <linux/crypto.h>
+#include <linux/mm.h>
+#include <linux/mount.h>
+#include <linux/scatterlist.h>
+#include <linux/namei.h>
+#include "ima.h"
+
+/*
+ * Calculate the file hash, using an open file descriptor if available.
+ */
+static int update_file_hash(struct file *f, struct path *path,
+ struct hash_desc *desc)
+{
+ struct file *file = f;
+ struct scatterlist sg[1];
+ loff_t i_size;
+ int rc = 0;
+ char *rbuf;
+ int offset = 0;
+
+ if (!file) {
+ struct dentry *de = dget(path->dentry);
+ struct vfsmount *mnt = mntget(path->mnt);
+ if (!de || !mnt) {
+ rc = -EINVAL;
+ goto err_out;
+ }
+ file = dentry_open(de, mnt, O_RDONLY);
+ if (IS_ERR(file)) {
+ ima_info("%s dentry_open failed\n", de->d_name.name);
+ rc = PTR_ERR(file);
+ file = NULL;
+ }
+err_out:
+ if (!file) {
+ dput(de);
+ mntput(mnt);
+ goto out;
+ }
+ }
+
+ if (!file->f_dentry || !file->f_dentry->d_inode) {
+ rc = -EINVAL;
+ goto out;
+ }
+
+ rbuf = kzalloc(PAGE_SIZE, GFP_KERNEL);
+ if (!rbuf) {
+ rc = -ENOMEM;
+ goto out;
+ }
+ i_size = i_size_read(file->f_dentry->d_inode);
+ while (offset < i_size) {
+ int rbuf_len;
+
+ rbuf_len = kernel_read(file, offset, rbuf, PAGE_SIZE);
+ if (rbuf_len < 0) {
+ rc = rbuf_len;
+ break;
+ }
+ offset += rbuf_len;
+ sg_set_buf(sg, rbuf, rbuf_len);
+
+ rc = crypto_hash_update(desc, sg, rbuf_len);
+ if (rc)
+ break;
+ }
+ kfree(rbuf);
+out:
+ if (file && !f)
+ fput(file); /* clean up dentry_open() */
+ return rc;
+}
+
+/*
+ * Calculate the MD5/SHA1 digest
+ */
+int ima_calc_hash(struct file *file, struct path *path, char *digest)
+{
+ struct hash_desc desc;
+ int rc;
+
+ if (!file && !path)
+ return -EINVAL;
+
+ desc.tfm = crypto_alloc_hash(ima_hash, 0, CRYPTO_ALG_ASYNC);
+ if (IS_ERR(desc.tfm)) {
+ ima_info("failed to load %s transform: %ld\n",
+ ima_hash, PTR_ERR(desc.tfm));
+ rc = PTR_ERR(desc.tfm);
+ return rc;
+ }
+ desc.flags = 0;
+ rc = crypto_hash_init(&desc);
+ if (rc)
+ goto out;
+
+ rc = update_file_hash(file, path, &desc);
+ if (!rc)
+ rc = crypto_hash_final(&desc, digest);
+out:
+ crypto_free_hash(desc.tfm);
+ return rc;
+}
+
+/*
+ * Calculate the hash of a given template
+ */
+int ima_calc_template_hash(int template_len, char *template, char *digest)
+{
+ struct hash_desc desc;
+ struct scatterlist sg[1];
+ int rc;
+
+ desc.tfm = crypto_alloc_hash(ima_hash, 0, CRYPTO_ALG_ASYNC);
+ if (IS_ERR(desc.tfm)) {
+ ima_info("failed to load %s transform: %ld\n",
+ ima_hash, PTR_ERR(desc.tfm));
+ rc = PTR_ERR(desc.tfm);
+ return rc;
+ }
+ desc.flags = 0;
+ rc = crypto_hash_init(&desc);
+ if (rc)
+ goto out;
+
+ sg_set_buf(sg, template, template_len);
+ rc = crypto_hash_update(&desc, sg, template_len);
+ if (!rc)
+ rc = crypto_hash_final(&desc, digest);
+out:
+ crypto_free_hash(desc.tfm);
+ return rc;
+}
diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c
new file mode 100644
index 0000000..0f9e516
--- /dev/null
+++ b/security/integrity/ima/ima_fs.c
@@ -0,0 +1,471 @@
+/*
+ * 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/module.h>
+#include <linux/seq_file.h>
+#include <linux/integrity.h>
+
+#include "ima.h"
+
+#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 struct file_operations ima_htable_violations_ops = {
+ .read = ima_show_htable_violations
+};
+
+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 struct file_operations ima_measurements_count_ops = {
+ .read = ima_show_measurements_count
+};
+
+/* returns pointer to hlist_node */
+static void *ima_measurements_start(struct seq_file *m, loff_t *pos)
+{
+ struct list_head *lpos;
+ loff_t l = *pos;
+ /* we need a lock since pos could point beyond last element */
+ rcu_read_lock();
+ list_for_each_rcu(lpos, &ima_measurements) {
+ if (!l--) {
+ rcu_read_unlock();
+ return lpos;
+ }
+ }
+ rcu_read_unlock();
+ return NULL;
+}
+
+static void *ima_measurements_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ /* lock protects when reading beyond last element
+ * against concurrent list-extension */
+ struct list_head *lpos = (struct list_head *)v;
+
+ rcu_read_lock();
+ lpos = rcu_dereference(lpos->next);
+ rcu_read_unlock();
+ (*pos)++;
+
+ return (lpos == &ima_measurements) ? NULL : lpos;
+}
+
+static void ima_measurements_stop(struct seq_file *m, void *v)
+{
+}
+
+/* print format:
+ * 32bit-le=pcr#
+ * char[20]=template digest
+ * 32bit-le=template size
+ * 32bit-le=template name size
+ * eventdata[n] = template name
+ *
+ */
+static int ima_measurements_show(struct seq_file *m, void *v)
+{
+ /* the list never shrinks, so we don't need a lock here */
+ struct list_head *lpos = v;
+ struct ima_queue_entry *qe;
+ struct ima_measure_entry *e;
+ struct ima_inode_measure_entry *entry;
+ const struct template_operations *template_ops;
+ int templatename_len;
+ int i;
+ u32 pcr = CONFIG_IMA_MEASURE_PCR_IDX;
+ char data[4];
+
+ /* get entry */
+ qe = list_entry(lpos, struct ima_queue_entry, later);
+ e = qe->entry;
+ if (e == NULL)
+ return -1;
+
+ /*
+ * 1st: PCRIndex
+ * PCR used is always the same (config option) in
+ * little-endian format
+ */
+ memcpy(data, &pcr, 4);
+ for (i = 0; i < 4; i++)
+ seq_putc(m, data[i]);
+
+ /* 2nd: template digest */
+ for (i = 0; i < 20; i++)
+ seq_putc(m, e->digest[i]);
+
+ /* 3rd: template name size */
+ templatename_len = strlen(e->template_name);
+ if (templatename_len > IMA_EVENT_NAME_LEN_MAX)
+ templatename_len = IMA_EVENT_NAME_LEN_MAX;
+
+ memcpy(data, &templatename_len, 4);
+ for (i = 0; i < 4; i++)
+ seq_putc(m, data[i]);
+
+ /* 4th: template name */
+ for (i = 0; i < templatename_len; i++)
+ seq_putc(m, e->template_name[i]);
+
+ /* 5th: template dependent */
+ entry = (struct ima_inode_measure_entry *)e->template;
+ if (integrity_find_template(e->template_name, &template_ops) == 0)
+ template_ops->display_template(m, entry, INTEGRITY_SHOW_BINARY);
+ else
+ seq_printf(m, " \n");
+ return 0;
+}
+
+static 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 struct file_operations ima_measurements_ops = {
+ .open = ima_measurements_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+void ima_template_show(struct seq_file *m, void *e,
+ enum integrity_show_type show)
+{
+ struct ima_inode_measure_entry *entry =
+ (struct ima_inode_measure_entry *)e;
+ int filename_len;
+ char data[4];
+ int i;
+
+ /* Display file digest */
+ if (ima_template_mode)
+ for (i = 0; i < 20; i++) {
+ switch (show) {
+ case INTEGRITY_SHOW_ASCII:
+ seq_printf(m, "%02x", entry->digest[i]);
+ break;
+ case INTEGRITY_SHOW_BINARY:
+ seq_putc(m, entry->digest[i]);
+ default:
+ break;
+ }
+ }
+
+ switch (show) {
+ case INTEGRITY_SHOW_ASCII:
+ seq_printf(m, " %s\n", entry->file_name);
+ break;
+ case INTEGRITY_SHOW_BINARY:
+ filename_len = strlen(entry->file_name);
+ if (filename_len > IMA_EVENT_NAME_LEN_MAX)
+ filename_len = IMA_EVENT_NAME_LEN_MAX;
+
+ memcpy(data, &filename_len, 4);
+ for (i = 0; i < 4; i++)
+ seq_putc(m, data[i]);
+ for (i = 0; i < filename_len; i++)
+ seq_putc(m, entry->file_name[i]);
+ default:
+ break;
+ }
+}
+
+/* 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 list_head *lpos = v;
+ struct ima_queue_entry *qe;
+ struct ima_measure_entry *e;
+ struct ima_inode_measure_entry *entry;
+ const struct template_operations *template_ops;
+ int i;
+
+ /* get entry */
+ qe = list_entry(lpos, struct ima_queue_entry, later);
+ 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 */
+ for (i = 0; i < 20; i++)
+ seq_printf(m, "%02x", e->digest[i]);
+
+ /* 3th: template name */
+ seq_printf(m, " %s ", e->template_name);
+
+ /* 4th: filename <= max + \'0' delimiter */
+ entry = (struct ima_inode_measure_entry *)e->template;
+ if (integrity_find_template(e->template_name, &template_ops) == 0)
+ template_ops->display_template(m, entry, INTEGRITY_SHOW_ASCII);
+ else
+ seq_printf(m, " \n");
+
+ return 0;
+}
+
+static 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 struct file_operations ima_ascii_measurements_ops = {
+ .open = ima_ascii_measurements_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+static char *get_tag(char *bufStart, char *bufEnd, char delimiter, int *taglen)
+{
+ char *bufp = bufStart;
+ char *tag;
+
+ /* Get start of tag */
+ while (bufp < bufEnd) {
+ if (*bufp == ' ') /* skip blanks */
+ while ((*bufp == ' ') && (bufp++ < bufEnd)) ;
+ else if (*bufp == '#') { /* skip comment */
+ while ((*bufp != '\n') && (bufp++ < bufEnd)) ;
+ bufp++;
+ } else if (*bufp == '\n') /* skip newline */
+ bufp++;
+ else if (*bufp == '\t') /* skip tabs */
+ bufp++;
+ else
+ break;
+ }
+ if (bufp < bufEnd)
+ tag = bufp;
+ else
+ return NULL;
+
+ /* Get tag */
+ *taglen = 0;
+ while ((bufp < bufEnd) && (*taglen == 0)) {
+ if ((*bufp == delimiter) || (*bufp == '\n')) {
+ *taglen = bufp - tag;
+ *bufp = '\0';
+ }
+ bufp++;
+ }
+ if (*taglen == 0) /* Didn't find end delimiter */
+ tag = NULL;
+ return tag;
+}
+
+static ssize_t ima_write_policy(struct file *file, const char __user *buf,
+ size_t buflen, loff_t *ppos)
+{
+ size_t rc = 0, datalen;
+ int action = 0;
+ char *data, *datap, *dataend;
+ char *subj_user = NULL, *subj_role = NULL, *subj_type = NULL;
+ char *obj_user = NULL, *obj_role = NULL, *obj_type = NULL;
+ char *func = NULL, *mask = NULL, *fsmagic = NULL, *uid = NULL;
+ int err = 0;
+ char *tag;
+ int taglen, i;
+
+ datalen = buflen > 4095 ? 4095 : buflen;
+ data = kmalloc(datalen + 1, GFP_KERNEL);
+ if (!data)
+ rc = -ENOMEM;
+
+ if (copy_from_user(data, buf, datalen)) {
+ kfree(data);
+ return -EFAULT;
+ }
+
+ rc = datalen;
+ *(data + datalen) = ' ';
+
+ datap = data;
+ dataend = data + datalen;
+
+ if (strncmp(datap, "measure", 7) == 0) {
+ datap += 8;
+ action = 1;
+ } else if (strncmp(datap, "dont_measure", 12) == 0)
+ datap += 13;
+ else /* bad format */
+ goto out;
+
+ for (i = 0; i < 6; i++) {
+ tag = get_tag(datap, dataend, ' ', &taglen);
+ if (!tag)
+ break;
+ if (strncmp(tag, "obj_user=", 9) == 0)
+ obj_user = tag + 9;
+ else if (strncmp(tag, "obj_role=", 9) == 0)
+ obj_role = tag + 9;
+ else if (strncmp(tag, "obj_type=", 9) == 0)
+ obj_type = tag + 9;
+ else if (strncmp(tag, "subj_user=", 10) == 0)
+ subj_user = tag + 10;
+ else if (strncmp(tag, "subj_role=", 10) == 0)
+ subj_role = tag + 10;
+ else if (strncmp(tag, "subj_type=", 10) == 0)
+ subj_type = tag + 10;
+ else if (strncmp(tag, "func=", 5) == 0)
+ func = tag + 5;
+ else if (strncmp(tag, "mask=", 5) == 0)
+ mask = tag + 5;
+ else if (strncmp(tag, "fsmagic=", 8) == 0)
+ fsmagic = tag + 8;
+ else if (strncmp(tag, "uid=", 4) == 0)
+ uid = tag + 4;
+ else { /* bad format */
+ err = 1;
+ break;
+ }
+ datap += taglen + 1;
+ }
+
+ if (!err) {
+ ima_info("%s subj: %s %s %s obj: %s %s %s %s %s %s %s\n",
+ action ? "measure " : "dont_measure",
+ subj_user, subj_role, subj_type,
+ obj_user, obj_role, obj_type,
+ func, mask, fsmagic, uid);
+ ima_add_rule(action, subj_user, subj_role, subj_type,
+ obj_user, obj_role, obj_type,
+ func, mask, fsmagic, uid);
+ }
+out:
+ if (!data)
+ kfree(data);
+ return rc;
+}
+
+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 int ima_release_policy(struct inode *inode, struct file *file)
+{
+ ima_update_policy();
+ securityfs_remove(ima_policy);
+ ima_policy = NULL;
+ return 0;
+}
+
+static struct file_operations ima_measure_policy_ops = {
+ .write = ima_write_policy,
+ .release = ima_release_policy
+};
+
+int ima_fs_init(void)
+{
+ ima_dir = securityfs_create_dir("ima", NULL);
+ if (!ima_dir || 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 (!binary_runtime_measurements || 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 (!ascii_runtime_measurements || 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 (!runtime_measurements_count || IS_ERR(runtime_measurements_count))
+ goto out;
+
+ violations =
+ securityfs_create_file("violations", S_IRUSR | S_IRGRP,
+ ima_dir, NULL, &ima_htable_violations_ops);
+ if (!violations || IS_ERR(violations))
+ goto out;
+
+ ima_policy = securityfs_create_file("policy",
+ S_IRUSR | S_IRGRP | S_IWUSR,
+ ima_dir, NULL,
+ &ima_measure_policy_ops);
+ ima_init_policy();
+ return 0;
+
+out:
+ 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;
+}
+
+void __exit ima_fs_cleanup(void)
+{
+ 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);
+}
diff --git a/security/integrity/ima/ima_init.c b/security/integrity/ima/ima_init.c
new file mode 100644
index 0000000..c3c87de
--- /dev/null
+++ b/security/integrity/ima/ima_init.c
@@ -0,0 +1,105 @@
+/*
+ * 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
+ */
+#include <linux/module.h>
+#include <linux/scatterlist.h>
+#include "ima.h"
+
+/* name for boot aggregate entry */
+static char *boot_aggregate_name = "boot_aggregate";
+static const char version[] = "v7.6 02/27/2007";
+
+int ima_used_chip;
+
+static void ima_add_boot_aggregate(void)
+{
+ /* cumulative sha1 over tpm registers 0-7 */
+ struct ima_measure_entry *entry;
+ size_t count;
+ int err;
+
+ /* create new entry for boot aggregate */
+ entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
+ if (entry == NULL) {
+ ima_add_violation(NULL, boot_aggregate_name,
+ "add_measure", "ENOMEM");
+ return;
+ }
+ count = strlen(boot_aggregate_name);
+ if (count > IMA_EVENT_NAME_LEN_MAX)
+ count = IMA_EVENT_NAME_LEN_MAX;
+ memcpy(entry->template_name, boot_aggregate_name, count);
+ entry->template_name[count] = '\0';
+ if (ima_used_chip) {
+ int i;
+ u8 pcr_i[20];
+ struct hash_desc desc;
+ struct crypto_hash *tfm;
+ struct scatterlist sg;
+
+ tfm = crypto_alloc_hash("sha1", 0, CRYPTO_ALG_ASYNC);
+ if (!tfm || IS_ERR(tfm)) {
+ kfree(entry);
+ ima_error("error initializing digest.\n");
+ return;
+ }
+ desc.tfm = tfm;
+ desc.flags = 0;
+ crypto_hash_init(&desc);
+
+ for (i = 0; i < 8; i++) {
+ ima_pcrread(i, pcr_i, sizeof(pcr_i));
+ /* now accumulate with current aggregate */
+ sg_init_one(&sg, (u8 *) pcr_i, 20);
+ crypto_hash_update(&desc, &sg, 20);
+ }
+ crypto_hash_final(&desc, entry->digest);
+ crypto_free_hash(tfm);
+ } else
+ memset(entry->digest, 0xff, 20);
+
+ /* now add measurement; if TPM bypassed, we have a ff..ff entry */
+ err = ima_add_measure_entry(entry, 0);
+ if (err < 0) {
+ kfree(entry);
+ ima_add_violation(NULL, boot_aggregate_name,
+ "add_measure", " ");
+ }
+}
+
+int ima_init(void)
+{
+ int rc;
+
+ ima_used_chip = 0;
+ rc = tpm_pcr_read(IMA_TPM, 0, NULL);
+ if (rc == 0)
+ ima_used_chip = 1;
+
+ if (!ima_used_chip)
+ ima_info("No TPM chip found(rc = %d), activating TPM-bypass!\n",
+ rc);
+
+ ima_create_htable(); /* for measurements */
+ ima_add_boot_aggregate(); /* boot aggregate must be first entry */
+
+ return ima_fs_init();
+}
+
+void __exit ima_cleanup(void)
+{
+ ima_fs_cleanup();
+}
diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
new file mode 100644
index 0000000..a11bc07
--- /dev/null
+++ b/security/integrity/ima/ima_main.c
@@ -0,0 +1,354 @@
+/*
+ * 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 LIM hooks
+ */
+#include <linux/module.h>
+#include <linux/integrity.h>
+#include <linux/magic.h>
+#include <linux/writeback.h>
+#include <linux/string.h>
+#include <linux/list.h>
+#include <linux/audit.h>
+#include <linux/ima.h>
+#include <linux/mman.h>
+#include <linux/namei.h>
+
+#include "ima.h"
+
+static bool ima_initialized = false;
+char *ima_hash = "sha1";
+static int __init hash_setup(char *str)
+{
+ char *op = "setup";
+ char *hash = "sha1";
+
+ if (strncmp(str, "md5", 3) == 0) {
+ op = "setup";
+ hash = "md5";
+ ima_hash = str;
+ } else if (strncmp(str, "sha1", 4) != 0) {
+ op = "hash_setup";
+ hash = "invalid_hash_type";
+ }
+ integrity_audit_msg(AUDIT_INTEGRITY_HASH, NULL, NULL, op, hash, 0);
+ return 1;
+}
+
+__setup("ima_hash=", hash_setup);
+
+/* For use when the LSM module makes LIM API calls */
+#ifdef CONFIG_IMA_BASE_HOOKS
+static int ima_base_hooks = 1;
+#else
+static int ima_base_hooks;
+#endif
+
+/*
+ * Setup the data structure used for the IMA LIM API calls.
+ */
+void ima_fixup_argsdata(struct ima_args_data *data, struct file *file,
+ struct path *path, int mask, int function)
+{
+ struct dentry *dentry = NULL;
+
+ data->file = file;
+ data->path = path;
+ data->mask = mask;
+ data->function = function;
+
+ if (file && file->f_dentry) {
+ data->dentry = dentry = file->f_dentry;
+ }
+ if (path && path->dentry) {
+ if (!dentry)
+ data->dentry = dentry = path->dentry;
+ }
+ if (dentry && dentry->d_inode) {
+ data->inode = dentry->d_inode;
+ }
+
+ return;
+}
+
+/**
+ * ima_file_free - called on close
+ * @file: pointer to file being closed
+ *
+ * Flag files that changed, based on i_version.
+ */
+static void ima_file_free(struct file *file)
+{
+ struct inode *inode = NULL;
+ struct ima_iint_cache *iint;
+
+ if (!file->f_dentry) /* can be NULL */
+ return;
+
+ inode = file->f_dentry->d_inode;
+ if (S_ISDIR(inode->i_mode))
+ return;
+ if ((file->f_mode & FMODE_WRITE) &&
+ (atomic_read(&inode->i_writecount) == 1)) {
+ iint = inode->i_integrity;
+ mutex_lock(&iint->mutex);
+ if (iint->version != inode->i_version)
+ iint->measured = 0;
+ mutex_unlock(&iint->mutex);
+ }
+}
+
+/**
+ * ima_alloc_integrity - allocate and attach an integrity structure
+ * @inode: the inode structure
+ *
+ * Returns 0 on success, -ENOMEM on failure
+ */
+static int ima_inode_alloc_integrity(struct inode *inode)
+{
+ struct ima_iint_cache *iint;
+
+ iint = kzalloc(sizeof(*iint), GFP_KERNEL);
+ if (!iint)
+ return -ENOMEM;
+
+ mutex_init(&iint->mutex);
+ inode->i_integrity = iint;
+ iint->version = inode->i_version;
+ return 0;
+}
+
+/**
+ * ima_inode_free_integrity - free the integrity structure
+ * @inode: the inode structure
+ */
+static void ima_inode_free_integrity(struct inode *inode)
+{
+ struct ima_iint_cache *iint = inode->i_integrity;
+
+ if (iint) {
+ inode->i_integrity = NULL;
+ kfree(iint);
+ }
+}
+
+/**
+ * ima_inode_permission - based on policy, collect/store measurement.
+ * @file: pointer to the file to be measured
+ * @path: pointer to a path structure containing the inode to be measured
+ * @mask: contains MAY_READ, MAY_WRITE, MAY_APPEND or MAY_EXECUTE
+ *
+ * Measure files being open for read, based on the ima_must_measure()
+ * policy decision.
+ *
+ * Invalidate the PCR:
+ * - 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.
+ *
+ * Return 0 on success, an error code on failure.
+ * (Based on the results of appraise_measurement().)
+ */
+static int ima_inode_permission(struct file *file, struct path *path, int mask)
+{
+ struct ima_data idata;
+ struct ima_args_data *data = &idata.data.args;
+ struct dentry *dentry;
+ struct inode *inode;
+
+ if (!ima_initialized)
+ return 0;
+
+ memset(&idata, 0, sizeof idata);
+ ima_fixup_argsdata(data, file, path, mask, INODE_PERMISSION);
+ inode = data->inode;
+
+ /* The file name is only a hint. */
+ dentry = file ? file->f_dentry : path->dentry;
+ data->filename = (!dentry->d_name.name) ? (char *)dentry->d_iname :
+ (char *)dentry->d_name.name;
+
+ /* Invalidate PCR, if a measured file is already open for read */
+ if ((mask == MAY_WRITE) || (mask == MAY_APPEND)) {
+ int mask_sav = data->mask;
+ int rc;
+
+ data->mask = MAY_READ;
+ rc = ima_must_measure(&idata);
+ if (!rc) {
+ if (atomic_read(&(data->dentry->d_count)) - 1 >
+ atomic_read(&(inode->i_writecount)))
+ ima_add_violation(inode, data->filename,
+ "invalid_pcr", "ToMToU");
+ }
+ data->mask = mask_sav;
+ goto out;
+ }
+
+ /* measure executables later */
+ if (mask & MAY_READ) {
+ int rc;
+
+ rc = ima_must_measure(&idata);
+ if (!rc) {
+ /* Invalidate PCR, if a measured file is
+ * already open for write.
+ */
+ if (atomic_read(&(inode->i_writecount)) > 0)
+ ima_add_violation(inode, data->filename,
+ "invalid_pcr",
+ "open_writers");
+
+ idata.type = IMA_DATA;
+ rc = ima_collect_measurement(&idata);
+ if (!rc)
+ ima_store_measurement(&idata);
+ }
+ }
+out:
+ return 0;
+}
+
+/**
+ * ima_file_mmap - based on policy, collect/store measurement.
+ * @file: pointer to the file to be measured
+ * @prot contains the protection that will be applied by the kernel.
+ *
+ * Measure files being mmapped executable based on the ima_must_measure()
+ * policy decision.
+ *
+ * Return 0 on success, an error code on failure.
+ * (Based on the results of appraise_measurement().)
+ */
+static int ima_file_mmap(struct file *file, unsigned long prot)
+{
+ struct ima_data idata;
+ struct ima_args_data *data = &idata.data.args;
+ int rc = 0;
+
+ if (!ima_initialized)
+ return 0;
+ if (!file || !file->f_dentry)
+ return rc;
+ if (!(prot & VM_EXEC))
+ return rc;
+
+ ima_fixup_argsdata(data, file, NULL, MAY_EXEC, FILE_MMAP);
+ data->filename = (!file->f_dentry->d_name.name) ?
+ (char *)file->f_dentry->d_iname :
+ (char *)file->f_dentry->d_name.name;
+
+ rc = ima_must_measure(&idata);
+ if (!rc) {
+ idata.type = IMA_DATA;
+ rc = ima_collect_measurement(&idata);
+ if (!rc)
+ ima_store_measurement(&idata);
+ }
+ return 0;
+}
+
+/**
+ * ima_bprm_check_integrity - 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.
+ *
+ * Return 0 on success, an error code on failure.
+ * (Based on the results of appraise_measurement().)
+ */
+static int ima_bprm_check_integrity(struct linux_binprm *bprm)
+{
+ struct ima_data idata;
+ struct ima_args_data *data = &idata.data.args;
+ int rc = 0;
+
+ if (!ima_initialized)
+ return 0;
+ ima_fixup_argsdata(data, bprm->file, NULL, MAY_EXEC, BPRM_CHECK);
+ data->filename = bprm->filename;
+
+ rc = ima_must_measure(&idata);
+ if (!rc) {
+ idata.type = IMA_DATA;
+ rc = ima_collect_measurement(&idata);
+ if (!rc)
+ ima_store_measurement(&idata);
+ }
+ return 0;
+}
+
+static const struct integrity_operations ima_integrity_ops = {
+ .bprm_check_integrity = ima_bprm_check_integrity,
+ .inode_permission = ima_inode_permission,
+ .inode_alloc_integrity = ima_inode_alloc_integrity,
+ .inode_free_integrity = ima_inode_free_integrity,
+ .file_free_integrity = ima_file_free,
+ .file_mmap = ima_file_mmap,
+};
+
+static const struct integrity_operations ima_base_ops = {
+ .inode_alloc_integrity = ima_inode_alloc_integrity,
+ .inode_free_integrity = ima_inode_free_integrity,
+ .file_free_integrity = ima_file_free,
+};
+
+/* Register the integrity ops early so that i_integrity is
+ * allocated at inode initialization.
+ */
+static int __init init_ops(void)
+{
+ int error;
+
+ if (ima_base_hooks)
+ error = register_integrity(&ima_base_ops);
+ else
+ error = register_integrity(&ima_integrity_ops);
+ return error;
+}
+
+/* After the TPM is available, start IMA
+ */
+static int __init init_ima(void)
+{
+ int error;
+
+ error = ima_init();
+ if (error)
+ goto out;
+ ima_initialized = true;
+ integrity_register_template("ima", &ima_template_ops);
+out:
+ return error;
+}
+
+static void __exit cleanup_ima(void)
+{
+ integrity_unregister_template("ima");
+ unregister_integrity(&ima_integrity_ops);
+ ima_cleanup();
+}
+
+security_initcall(init_ops); /* Register the integrity ops early */
+late_initcall(init_ima); /* Start IMA after the TPM is available */
+module_exit(cleanup_ima);
+
+MODULE_DESCRIPTION("Integrity Measurement Architecture");
+MODULE_LICENSE("GPL");
diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
new file mode 100644
index 0000000..f7b863f
--- /dev/null
+++ b/security/integrity/ima/ima_policy.c
@@ -0,0 +1,334 @@
+/*
+ * 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
+ - load a policy ruleset
+ *
+ */
+#include <linux/module.h>
+#include <linux/list.h>
+#include <linux/audit.h>
+#include <linux/security.h>
+#include <linux/integrity.h>
+#include <linux/magic.h>
+
+#include "ima.h"
+
+#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
+};
+
+#define audit_type(type) AUDIT_ ##type
+#define lsm_type(type) LSM_ ##type
+
+struct ima_measure_rule_entry {
+ struct list_head list;
+ int action;
+ struct {
+ void *rule;
+ int type; /* audit type */
+ } lsm_field[MAX_LSM_RULES];
+ uint flags;
+ enum lim_hooks func;
+ int mask;
+ ulong fsmagic;
+ uid_t uid;
+};
+
+/* flags definitions */
+#define IMA_FUNC 0x0001
+#define IMA_MASK 0x0002
+#define IMA_FSMAGIC 0x0004
+#define IMA_UID 0x0008
+
+/* Without LSM specific knowledge, default policy can only be
+ * written in terms of .action, .func, .mask, .fsmagic, and .uid
+ */
+static struct ima_measure_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 = SECURITYFS_MAGIC,
+ .flags = IMA_FSMAGIC},
+ {.action = MEASURE,.func = FILE_MMAP,.mask = MAY_EXEC,
+ .flags = IMA_FUNC | IMA_MASK},
+ {.action = MEASURE,.func = BPRM_CHECK,.mask = MAY_EXEC,
+ .flags = IMA_FUNC | IMA_MASK},
+ {.action = MEASURE,.func = INODE_PERMISSION,.mask = MAY_READ,.uid = 0,
+ .flags = IMA_FUNC | IMA_MASK | IMA_UID}
+};
+
+static struct list_head measure_default_rules;
+static struct list_head measure_policy_rules;
+static struct list_head *ima_measure;
+
+static DEFINE_MUTEX(ima_measure_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_measure_rule_entry *rule,
+ struct inode *inode, enum lim_hooks func, int mask)
+{
+ struct task_struct *tsk = current;
+ int i;
+
+ if ((rule->flags & IMA_FUNC) && rule->func != func)
+ return false;
+ if ((rule->flags & IMA_MASK) && rule->mask != mask)
+ return false;
+ if ((rule->flags & IMA_FSMAGIC)
+ && rule->fsmagic != inode->i_sb->s_magic)
+ return false;
+ if ((rule->flags & IMA_UID) && rule->uid != tsk->uid)
+ return false;
+ for (i = 0; i < MAX_LSM_RULES; i++) {
+ int rc;
+ u32 osid, sid;
+
+ if (!rule->lsm_field[i].rule)
+ continue;
+
+ 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_field[i].type,
+ AUDIT_EQUAL,
+ rule->lsm_field[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_field[i].type,
+ AUDIT_EQUAL,
+ rule->lsm_field[i].rule,
+ NULL);
+ default:
+ break;
+ }
+ if (!rc)
+ return false;
+ }
+ return true;
+}
+
+/**
+ * ima_match_policy - decision based on LSM and other conditions
+ * @inode: pointer to an inode
+ * @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. Returns rule action on rule match, 0 on failure.
+ */
+int ima_match_policy(struct inode *inode, enum lim_hooks func, int mask)
+{
+ struct ima_measure_rule_entry *entry;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(entry, ima_measure, list) {
+ bool rc;
+
+ rc = ima_match_rules(entry, inode, func, mask);
+ if (rc) {
+ rcu_read_unlock();
+ return entry->action;
+ }
+ }
+ rcu_read_unlock();
+ return 0;
+}
+
+/**
+ * ima_init_policy - initialize the default and policy measure rules.
+ */
+void ima_init_policy(void)
+{
+ int i;
+
+ INIT_LIST_HEAD(&measure_default_rules);
+ for (i = 0; i < ARRAY_SIZE(default_rules); i++)
+ list_add_tail(&default_rules[i].list, &measure_default_rules);
+ ima_measure = &measure_default_rules;
+
+ INIT_LIST_HEAD(&measure_policy_rules);
+}
+
+/**
+ * ima_update_policy - update default_rules with new measure rules
+ *
+ * Wait to update the default rules with a complete new set of measure rules.
+ */
+void ima_update_policy(void)
+{
+ char *op = "policy_update";
+ char *cause = "already exists";
+ int result = 1;
+
+ if (ima_measure == &measure_default_rules) {
+ ima_measure = &measure_policy_rules;
+ cause = "complete";
+ result = 0;
+ }
+ integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL,
+ NULL, op, cause, result);
+}
+
+/**
+ * ima_add_rule - add ima measure rules
+ * @action: integer 1 indicating MEASURE, 0 indicating DONT_MEASURE
+ * @subj_user: pointer to an LSM subject's user value
+ * @subj_role: pointer to an LSM subject's role value
+ * @subj_type: pointer to an LSM subject's type value
+ * @obj_user: pointer to an LSM object's user value
+ * @obj_role: pointer to an LSM object's role value
+ * @obj_type: pointer to an LSM object's type value
+ * @func: LIM hook identifier
+ * @mask: requested action (MAY_READ | MAY_WRITE | MAY_APPEND | MAY_EXEC)
+ * @fsmagic: fs magic hex value string
+ * @uid: uid value string
+ *
+ * Returns 0 on success, an error code on failure.
+ */
+int ima_add_rule(int action,
+ char *subj_user, char *subj_role, char *subj_type,
+ char *obj_user, char *obj_role, char *obj_type,
+ char *func, char *mask, char *fsmagic, char *uid)
+{
+ struct ima_measure_rule_entry *entry;
+ int i, result = 0;
+
+ /* Prevent installed policy from changing */
+ if (ima_measure != &measure_default_rules) {
+ integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL,
+ NULL, "policy_update", "already exists", 1);
+ return -EACCES;
+ }
+
+ entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+ INIT_LIST_HEAD(&entry->list);
+ if (action < 0 || action > 1)
+ result = -EINVAL;
+ else
+ entry->action = action;
+
+ if (!result && subj_user) {
+ i = lsm_type(SUBJ_USER);
+ entry->lsm_field[i].type = audit_type(SUBJ_USER);
+ result = security_filter_rule_init(entry->lsm_field[i].type,
+ AUDIT_EQUAL, subj_user,
+ &entry->lsm_field[i].rule);
+ }
+ if (!result && subj_role) {
+ i = lsm_type(SUBJ_ROLE);
+ entry->lsm_field[i].type = audit_type(SUBJ_ROLE);
+ result = security_filter_rule_init(entry->lsm_field[i].type,
+ AUDIT_EQUAL, subj_role,
+ &entry->lsm_field[i].rule);
+ }
+ if (!result && subj_type) {
+ i = lsm_type(SUBJ_TYPE);
+ entry->lsm_field[i].type = audit_type(SUBJ_TYPE);
+ result = security_filter_rule_init(entry->lsm_field[i].type,
+ AUDIT_EQUAL, subj_type,
+ &entry->lsm_field[i].rule);
+ }
+ if (!result && obj_user) {
+ i = lsm_type(OBJ_USER);
+ entry->lsm_field[i].type = audit_type(OBJ_USER);
+ result = security_filter_rule_init(entry->lsm_field[i].type,
+ AUDIT_EQUAL, obj_user,
+ &entry->lsm_field[i].rule);
+ }
+ if (!result && obj_role) {
+ i = lsm_type(OBJ_ROLE);
+ entry->lsm_field[i].type = audit_type(OBJ_ROLE);
+ result = security_filter_rule_init(entry->lsm_field[i].type,
+ AUDIT_EQUAL, obj_role,
+ &entry->lsm_field[i].rule);
+ }
+ if (!result && obj_type) {
+ i = lsm_type(OBJ_TYPE);
+ entry->lsm_field[i].type = audit_type(OBJ_TYPE);
+ result = security_filter_rule_init(entry->lsm_field[i].type,
+ AUDIT_EQUAL, obj_type,
+ &entry->lsm_field[i].rule);
+ }
+ if (!result && func) {
+ if (strcmp(func, "INODE_PERMISSION") == 0)
+ entry->func = INODE_PERMISSION;
+ else if (strcmp(func, "FILE_MMAP") == 0)
+ entry->func = FILE_MMAP;
+ else if (strcmp(func, "BPRM_CHECK") == 0)
+ entry->func = BPRM_CHECK;
+ else
+ result = -EINVAL;
+ if (!result)
+ entry->flags |= IMA_FUNC;
+ }
+ if (!result && mask) {
+ if (strcmp(mask, "MAY_EXEC") == 0)
+ entry->mask = MAY_EXEC;
+ else if (strcmp(mask, "MAY_WRITE") == 0)
+ entry->mask = MAY_WRITE;
+ else if (strcmp(mask, "MAY_READ") == 0)
+ entry->mask = MAY_READ;
+ else if (strcmp(mask, "MAY_APPEND") == 0)
+ entry->mask = MAY_APPEND;
+ else
+ result = -EINVAL;
+ if (!result)
+ entry->flags |= IMA_MASK;
+ }
+ if (!result && fsmagic) {
+ int rc;
+
+ rc = strict_strtoul(fsmagic, 16, &entry->fsmagic);
+ if (rc)
+ result = -EINVAL;
+ else
+ entry->flags |= IMA_FSMAGIC;
+ }
+ if (!result && uid) {
+ int rc;
+ ulong lnum;
+
+ rc = strict_strtoul(uid, 10, &lnum);
+ if (rc)
+ result = -EINVAL;
+ else {
+ entry->uid = (uid_t) lnum;
+ if (entry->uid != lnum)
+ result = -EINVAL;
+ else
+ entry->flags |= IMA_UID;
+ }
+ }
+ if (!result) {
+ mutex_lock(&ima_measure_mutex);
+ list_add_tail(&entry->list, &measure_policy_rules);
+ mutex_unlock(&ima_measure_mutex);
+ }
+ return result;
+}
diff --git a/security/integrity/ima/ima_queue.c b/security/integrity/ima/ima_queue.c
new file mode 100644
index 0000000..1cb4f03
--- /dev/null
+++ b/security/integrity/ima/ima_queue.c
@@ -0,0 +1,124 @@
+/*
+ * 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 IMA 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.
+ */
+#include <linux/module.h>
+
+#include "ima.h"
+
+struct list_head ima_measurements; /* list of all measurements */
+struct ima_h_table ima_htable; /* key: inode (before secure-hashing a file) */
+
+/* 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);
+
+void ima_create_htable(void)
+{
+ int i;
+
+ INIT_LIST_HEAD(&ima_measurements);
+ atomic_set(&ima_htable.len, 0);
+ atomic_long_set(&ima_htable.violations, 0);
+ ima_htable.max_htable_size = IMA_MEASURE_HTABLE_SIZE;
+
+ for (i = 0; i < ima_htable.max_htable_size; i++) {
+ INIT_HLIST_HEAD(&ima_htable.queue[i]);
+ atomic_set(&ima_htable.queue_len[i], 0);
+ }
+}
+
+struct ima_queue_entry *ima_lookup_digest_entry(u8 *digest_value)
+{
+ struct ima_queue_entry *qe, *ret = NULL;
+ unsigned int key;
+ struct hlist_node *pos;
+
+ key = IMA_HASH_KEY(digest_value);
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(qe, pos, &ima_htable.queue[key], hnext) {
+ if (memcmp(qe->entry->digest, digest_value, 20) == 0) {
+ ret = qe;
+ break;
+ }
+ }
+ rcu_read_unlock();
+ return ret;
+}
+
+/* Called with mutex held */
+static int ima_add_digest_entry(struct ima_measure_entry *entry)
+{
+ struct ima_queue_entry *qe;
+ unsigned int key;
+
+ key = IMA_HASH_KEY(entry->digest);
+ qe = kmalloc(sizeof(*entry), GFP_KERNEL);
+ if (qe == NULL) {
+ ima_error("OUT OF MEMORY ERROR creating queue entry.\n");
+ return -ENOMEM;
+ }
+ qe->entry = entry;
+
+ hlist_add_head_rcu(&qe->hnext, &ima_htable.queue[key]);
+ atomic_inc(&ima_htable.queue_len[key]);
+ return 0;
+}
+
+int ima_add_measure_entry(struct ima_measure_entry *entry, int violation)
+{
+ struct ima_queue_entry *qe;
+ int error = 0;
+
+ mutex_lock(&ima_extend_list_mutex);
+ if (!violation) {
+ if (ima_lookup_digest_entry(entry->digest)) {
+ error = -EEXIST;
+ goto out;
+ }
+ }
+ qe = kmalloc(sizeof(struct ima_queue_entry), GFP_KERNEL);
+ if (qe == NULL) {
+ ima_error("OUT OF MEMORY in %s.\n", __func__);
+ error = -ENOMEM;
+ goto out;
+ }
+ qe->entry = entry;
+
+ INIT_LIST_HEAD(&qe->later);
+ list_add_tail_rcu(&qe->later, &ima_measurements);
+
+ atomic_long_inc(&ima_htable.len);
+ if (ima_add_digest_entry(entry)) {
+ error = -ENOMEM;
+ goto out;
+ }
+ if (violation) { /* Replace 0x00 with 0xFF */
+ u8 digest[IMA_DIGEST_SIZE];
+
+ memset(digest, 0xff, sizeof digest);
+ ima_extend(digest);
+ } else
+ ima_extend(entry->digest);
+out:
+ mutex_unlock(&ima_extend_list_mutex);
+ return error;
+}
--
1.5.5.1
^ permalink raw reply related [flat|nested] 35+ messages in thread