Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates from James Morris:
"Highlights:
- Integrity: add local fs integrity verification to detect offline
attacks
- Integrity: add digital signature verification
- Simple stacking of Yama with other LSMs (per LSS discussions)
- IBM vTPM support on ppc64
- Add new driver for Infineon I2C TIS TPM
- Smack: add rule revocation for subject labels"
Fixed conflicts with the user namespace support in kernel/auditsc.c and
security/integrity/ima/ima_policy.c.
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (39 commits)
Documentation: Update git repository URL for Smack userland tools
ima: change flags container data type
Smack: setprocattr memory leak fix
Smack: implement revoking all rules for a subject label
Smack: remove task_wait() hook.
ima: audit log hashes
ima: generic IMA action flag handling
ima: rename ima_must_appraise_or_measure
audit: export audit_log_task_info
tpm: fix tpm_acpi sparse warning on different address spaces
samples/seccomp: fix 31 bit build on s390
ima: digital signature verification support
ima: add support for different security.ima data types
ima: add ima_inode_setxattr/removexattr function and calls
ima: add inode_post_setattr call
ima: replace iint spinblock with rwlock/read_lock
ima: allocating iint improvements
ima: add appraise action keywords and default rules
ima: integrity appraisal extension
vfs: move ima_file_free before releasing the file
...
diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c
index 8901501..eb54845 100644
--- a/security/integrity/evm/evm_main.c
+++ b/security/integrity/evm/evm_main.c
@@ -34,6 +34,9 @@
#ifdef CONFIG_SECURITY_SMACK
XATTR_NAME_SMACK,
#endif
+#ifdef CONFIG_IMA_APPRAISE
+ XATTR_NAME_IMA,
+#endif
XATTR_NAME_CAPS,
NULL
};
diff --git a/security/integrity/iint.c b/security/integrity/iint.c
index 399641c..d82a5a1 100644
--- a/security/integrity/iint.c
+++ b/security/integrity/iint.c
@@ -22,7 +22,7 @@
#include "integrity.h"
static struct rb_root integrity_iint_tree = RB_ROOT;
-static DEFINE_SPINLOCK(integrity_iint_lock);
+static DEFINE_RWLOCK(integrity_iint_lock);
static struct kmem_cache *iint_cache __read_mostly;
int iint_initialized;
@@ -35,8 +35,6 @@
struct integrity_iint_cache *iint;
struct rb_node *n = integrity_iint_tree.rb_node;
- assert_spin_locked(&integrity_iint_lock);
-
while (n) {
iint = rb_entry(n, struct integrity_iint_cache, rb_node);
@@ -63,9 +61,9 @@
if (!IS_IMA(inode))
return NULL;
- spin_lock(&integrity_iint_lock);
+ read_lock(&integrity_iint_lock);
iint = __integrity_iint_find(inode);
- spin_unlock(&integrity_iint_lock);
+ read_unlock(&integrity_iint_lock);
return iint;
}
@@ -74,59 +72,53 @@
{
iint->version = 0;
iint->flags = 0UL;
+ iint->ima_status = INTEGRITY_UNKNOWN;
iint->evm_status = INTEGRITY_UNKNOWN;
kmem_cache_free(iint_cache, iint);
}
/**
- * integrity_inode_alloc - allocate an iint associated with an inode
+ * integrity_inode_get - find or allocate an iint associated with an inode
* @inode: pointer to the inode
+ * @return: allocated iint
+ *
+ * Caller must lock i_mutex
*/
-int integrity_inode_alloc(struct inode *inode)
+struct integrity_iint_cache *integrity_inode_get(struct inode *inode)
{
struct rb_node **p;
- struct rb_node *new_node, *parent = NULL;
- struct integrity_iint_cache *new_iint, *test_iint;
- int rc;
+ struct rb_node *node, *parent = NULL;
+ struct integrity_iint_cache *iint, *test_iint;
- new_iint = kmem_cache_alloc(iint_cache, GFP_NOFS);
- if (!new_iint)
- return -ENOMEM;
+ iint = integrity_iint_find(inode);
+ if (iint)
+ return iint;
- new_iint->inode = inode;
- new_node = &new_iint->rb_node;
+ iint = kmem_cache_alloc(iint_cache, GFP_NOFS);
+ if (!iint)
+ return NULL;
- mutex_lock(&inode->i_mutex); /* i_flags */
- spin_lock(&integrity_iint_lock);
+ write_lock(&integrity_iint_lock);
p = &integrity_iint_tree.rb_node;
while (*p) {
parent = *p;
test_iint = rb_entry(parent, struct integrity_iint_cache,
rb_node);
- rc = -EEXIST;
if (inode < test_iint->inode)
p = &(*p)->rb_left;
- else if (inode > test_iint->inode)
- p = &(*p)->rb_right;
else
- goto out_err;
+ p = &(*p)->rb_right;
}
+ iint->inode = inode;
+ node = &iint->rb_node;
inode->i_flags |= S_IMA;
- rb_link_node(new_node, parent, p);
- rb_insert_color(new_node, &integrity_iint_tree);
+ rb_link_node(node, parent, p);
+ rb_insert_color(node, &integrity_iint_tree);
- spin_unlock(&integrity_iint_lock);
- mutex_unlock(&inode->i_mutex); /* i_flags */
-
- return 0;
-out_err:
- spin_unlock(&integrity_iint_lock);
- mutex_unlock(&inode->i_mutex); /* i_flags */
- iint_free(new_iint);
-
- return rc;
+ write_unlock(&integrity_iint_lock);
+ return iint;
}
/**
@@ -142,10 +134,10 @@
if (!IS_IMA(inode))
return;
- spin_lock(&integrity_iint_lock);
+ write_lock(&integrity_iint_lock);
iint = __integrity_iint_find(inode);
rb_erase(&iint->rb_node, &integrity_iint_tree);
- spin_unlock(&integrity_iint_lock);
+ write_unlock(&integrity_iint_lock);
iint_free(iint);
}
@@ -157,7 +149,7 @@
memset(iint, 0, sizeof *iint);
iint->version = 0;
iint->flags = 0UL;
- mutex_init(&iint->mutex);
+ iint->ima_status = INTEGRITY_UNKNOWN;
iint->evm_status = INTEGRITY_UNKNOWN;
}
diff --git a/security/integrity/ima/Kconfig b/security/integrity/ima/Kconfig
index b9c1219..d232c73 100644
--- a/security/integrity/ima/Kconfig
+++ b/security/integrity/ima/Kconfig
@@ -11,6 +11,7 @@
select CRYPTO_SHA1
select TCG_TPM if HAS_IOMEM && !UML
select TCG_TIS if TCG_TPM && X86
+ select TCG_IBMVTPM if TCG_TPM && PPC64
help
The Trusted Computing Group(TCG) runtime Integrity
Measurement Architecture(IMA) maintains a list of hash
@@ -55,3 +56,18 @@
default y
help
Disabling this option will disregard LSM based policy rules.
+
+config IMA_APPRAISE
+ bool "Appraise integrity measurements"
+ depends on IMA
+ default n
+ help
+ This option enables local measurement integrity appraisal.
+ It requires the system to be labeled with a security extended
+ attribute containing the file hash measurement. To protect
+ the security extended attributes from offline attack, enable
+ and configure EVM.
+
+ For more information on integrity appraisal refer to:
+ <http://linux-ima.sourceforge.net>
+ If unsure, say N.
diff --git a/security/integrity/ima/Makefile b/security/integrity/ima/Makefile
index 5f740f6..3f2ca6b 100644
--- a/security/integrity/ima/Makefile
+++ b/security/integrity/ima/Makefile
@@ -8,3 +8,4 @@
ima-y := ima_fs.o ima_queue.o ima_init.o ima_main.o ima_crypto.o ima_api.o \
ima_policy.o
ima-$(CONFIG_IMA_AUDIT) += ima_audit.o
+ima-$(CONFIG_IMA_APPRAISE) += ima_appraise.o
diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index e7c99fd..8180add 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -40,6 +40,7 @@
extern int ima_initialized;
extern int ima_used_chip;
extern char *ima_hash;
+extern int ima_appraise;
/* IMA inode template definition */
struct ima_template_data {
@@ -107,11 +108,14 @@
}
/* LIM API function definitions */
+int ima_get_action(struct inode *inode, int mask, int function);
int ima_must_measure(struct inode *inode, int mask, int function);
int ima_collect_measurement(struct integrity_iint_cache *iint,
struct file *file);
void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file,
const unsigned char *filename);
+void ima_audit_measurement(struct integrity_iint_cache *iint,
+ const unsigned char *filename);
int ima_store_template(struct ima_template_entry *entry, int violation,
struct inode *inode);
void ima_template_show(struct seq_file *m, void *e, enum ima_show_type show);
@@ -123,14 +127,45 @@
struct integrity_iint_cache *integrity_iint_find(struct inode *inode);
/* IMA policy related functions */
-enum ima_hooks { FILE_CHECK = 1, FILE_MMAP, BPRM_CHECK };
+enum ima_hooks { FILE_CHECK = 1, FILE_MMAP, BPRM_CHECK, POST_SETATTR };
-int ima_match_policy(struct inode *inode, enum ima_hooks func, int mask);
+int ima_match_policy(struct inode *inode, enum ima_hooks func, int mask,
+ int flags);
void ima_init_policy(void);
void ima_update_policy(void);
ssize_t ima_parse_add_rule(char *);
void ima_delete_rules(void);
+/* Appraise integrity measurements */
+#define IMA_APPRAISE_ENFORCE 0x01
+#define IMA_APPRAISE_FIX 0x02
+
+#ifdef CONFIG_IMA_APPRAISE
+int ima_appraise_measurement(struct integrity_iint_cache *iint,
+ struct file *file, const unsigned char *filename);
+int ima_must_appraise(struct inode *inode, enum ima_hooks func, int mask);
+void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file);
+
+#else
+static inline int ima_appraise_measurement(struct integrity_iint_cache *iint,
+ struct file *file,
+ const unsigned char *filename)
+{
+ return INTEGRITY_UNKNOWN;
+}
+
+static inline int ima_must_appraise(struct inode *inode,
+ enum ima_hooks func, int mask)
+{
+ return 0;
+}
+
+static inline void ima_update_xattr(struct integrity_iint_cache *iint,
+ struct file *file)
+{
+}
+#endif
+
/* LSM based policy rules require audit */
#ifdef CONFIG_IMA_LSM_RULES
diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c
index 032ff03..b356884 100644
--- a/security/integrity/ima/ima_api.c
+++ b/security/integrity/ima/ima_api.c
@@ -9,13 +9,17 @@
* License.
*
* File: ima_api.c
- * Implements must_measure, collect_measurement, store_measurement,
- * and store_template.
+ * Implements must_appraise_or_measure, collect_measurement,
+ * appraise_measurement, store_measurement and store_template.
*/
#include <linux/module.h>
#include <linux/slab.h>
-
+#include <linux/file.h>
+#include <linux/fs.h>
+#include <linux/xattr.h>
+#include <linux/evm.h>
#include "ima.h"
+
static const char *IMA_TEMPLATE_NAME = "ima";
/*
@@ -93,7 +97,7 @@
}
/**
- * ima_must_measure - measure decision based on policy.
+ * ima_get_action - appraise & measure decision based on policy.
* @inode: pointer to inode to measure
* @mask: contains the permission mask (MAY_READ, MAY_WRITE, MAY_EXECUTE)
* @function: calling function (FILE_CHECK, BPRM_CHECK, FILE_MMAP)
@@ -105,15 +109,22 @@
* 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.
-*/
+ * Returns IMA_MEASURE, IMA_APPRAISE mask.
+ *
+ */
+int ima_get_action(struct inode *inode, int mask, int function)
+{
+ int flags = IMA_MEASURE | IMA_AUDIT | IMA_APPRAISE;
+
+ if (!ima_appraise)
+ flags &= ~IMA_APPRAISE;
+
+ return ima_match_policy(inode, function, mask, flags);
+}
+
int ima_must_measure(struct inode *inode, int mask, int function)
{
- int must_measure;
-
- must_measure = ima_match_policy(inode, function, mask);
- return must_measure ? 0 : -EACCES;
+ return ima_match_policy(inode, function, mask, IMA_MEASURE);
}
/*
@@ -129,16 +140,24 @@
int ima_collect_measurement(struct integrity_iint_cache *iint,
struct file *file)
{
- int result = -EEXIST;
+ struct inode *inode = file->f_dentry->d_inode;
+ const char *filename = file->f_dentry->d_name.name;
+ int result = 0;
- if (!(iint->flags & IMA_MEASURED)) {
+ if (!(iint->flags & IMA_COLLECTED)) {
u64 i_version = file->f_dentry->d_inode->i_version;
- memset(iint->digest, 0, IMA_DIGEST_SIZE);
- result = ima_calc_hash(file, iint->digest);
- if (!result)
+ iint->ima_xattr.type = IMA_XATTR_DIGEST;
+ result = ima_calc_hash(file, iint->ima_xattr.digest);
+ if (!result) {
iint->version = i_version;
+ iint->flags |= IMA_COLLECTED;
+ }
}
+ if (result)
+ integrity_audit_msg(AUDIT_INTEGRITY_DATA, inode,
+ filename, "collect_data", "failed",
+ result, 0);
return result;
}
@@ -167,6 +186,9 @@
struct ima_template_entry *entry;
int violation = 0;
+ if (iint->flags & IMA_MEASURED)
+ return;
+
entry = kmalloc(sizeof(*entry), GFP_KERNEL);
if (!entry) {
integrity_audit_msg(AUDIT_INTEGRITY_PCR, inode, filename,
@@ -174,7 +196,7 @@
return;
}
memset(&entry->template, 0, sizeof(entry->template));
- memcpy(entry->template.digest, iint->digest, IMA_DIGEST_SIZE);
+ memcpy(entry->template.digest, iint->ima_xattr.digest, IMA_DIGEST_SIZE);
strcpy(entry->template.file_name,
(strlen(filename) > IMA_EVENT_NAME_LEN_MAX) ?
file->f_dentry->d_name.name : filename);
@@ -185,3 +207,33 @@
if (result < 0)
kfree(entry);
}
+
+void ima_audit_measurement(struct integrity_iint_cache *iint,
+ const unsigned char *filename)
+{
+ struct audit_buffer *ab;
+ char hash[(IMA_DIGEST_SIZE * 2) + 1];
+ int i;
+
+ if (iint->flags & IMA_AUDITED)
+ return;
+
+ for (i = 0; i < IMA_DIGEST_SIZE; i++)
+ hex_byte_pack(hash + (i * 2), iint->ima_xattr.digest[i]);
+ hash[i * 2] = '\0';
+
+ ab = audit_log_start(current->audit_context, GFP_KERNEL,
+ AUDIT_INTEGRITY_RULE);
+ if (!ab)
+ return;
+
+ audit_log_format(ab, "file=");
+ audit_log_untrustedstring(ab, filename);
+ audit_log_format(ab, " hash=");
+ audit_log_untrustedstring(ab, hash);
+
+ audit_log_task_info(ab, current);
+ audit_log_end(ab);
+
+ iint->flags |= IMA_AUDITED;
+}
diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c
new file mode 100644
index 0000000..0aa43bd
--- /dev/null
+++ b/security/integrity/ima/ima_appraise.c
@@ -0,0 +1,263 @@
+/*
+ * Copyright (C) 2011 IBM Corporation
+ *
+ * Author:
+ * Mimi Zohar <zohar@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 2 of the License.
+ */
+#include <linux/module.h>
+#include <linux/file.h>
+#include <linux/fs.h>
+#include <linux/xattr.h>
+#include <linux/magic.h>
+#include <linux/ima.h>
+#include <linux/evm.h>
+
+#include "ima.h"
+
+static int __init default_appraise_setup(char *str)
+{
+ if (strncmp(str, "off", 3) == 0)
+ ima_appraise = 0;
+ else if (strncmp(str, "fix", 3) == 0)
+ ima_appraise = IMA_APPRAISE_FIX;
+ return 1;
+}
+
+__setup("ima_appraise=", default_appraise_setup);
+
+/*
+ * ima_must_appraise - set appraise flag
+ *
+ * Return 1 to appraise
+ */
+int ima_must_appraise(struct inode *inode, enum ima_hooks func, int mask)
+{
+ if (!ima_appraise)
+ return 0;
+
+ return ima_match_policy(inode, func, mask, IMA_APPRAISE);
+}
+
+static void ima_fix_xattr(struct dentry *dentry,
+ struct integrity_iint_cache *iint)
+{
+ iint->ima_xattr.type = IMA_XATTR_DIGEST;
+ __vfs_setxattr_noperm(dentry, XATTR_NAME_IMA, (u8 *)&iint->ima_xattr,
+ sizeof iint->ima_xattr, 0);
+}
+
+/*
+ * ima_appraise_measurement - appraise file measurement
+ *
+ * Call evm_verifyxattr() to verify the integrity of 'security.ima'.
+ * Assuming success, compare the xattr hash with the collected measurement.
+ *
+ * Return 0 on success, error code otherwise
+ */
+int ima_appraise_measurement(struct integrity_iint_cache *iint,
+ struct file *file, const unsigned char *filename)
+{
+ struct dentry *dentry = file->f_dentry;
+ struct inode *inode = dentry->d_inode;
+ struct evm_ima_xattr_data *xattr_value = NULL;
+ enum integrity_status status = INTEGRITY_UNKNOWN;
+ const char *op = "appraise_data";
+ char *cause = "unknown";
+ int rc;
+
+ if (!ima_appraise)
+ return 0;
+ if (!inode->i_op->getxattr)
+ return INTEGRITY_UNKNOWN;
+
+ if (iint->flags & IMA_APPRAISED)
+ return iint->ima_status;
+
+ rc = vfs_getxattr_alloc(dentry, XATTR_NAME_IMA, (char **)&xattr_value,
+ 0, GFP_NOFS);
+ if (rc <= 0) {
+ if (rc && rc != -ENODATA)
+ goto out;
+
+ cause = "missing-hash";
+ status =
+ (inode->i_size == 0) ? INTEGRITY_PASS : INTEGRITY_NOLABEL;
+ goto out;
+ }
+
+ status = evm_verifyxattr(dentry, XATTR_NAME_IMA, xattr_value, rc, iint);
+ if ((status != INTEGRITY_PASS) && (status != INTEGRITY_UNKNOWN)) {
+ if ((status == INTEGRITY_NOLABEL)
+ || (status == INTEGRITY_NOXATTRS))
+ cause = "missing-HMAC";
+ else if (status == INTEGRITY_FAIL)
+ cause = "invalid-HMAC";
+ goto out;
+ }
+
+ switch (xattr_value->type) {
+ case IMA_XATTR_DIGEST:
+ rc = memcmp(xattr_value->digest, iint->ima_xattr.digest,
+ IMA_DIGEST_SIZE);
+ if (rc) {
+ cause = "invalid-hash";
+ status = INTEGRITY_FAIL;
+ print_hex_dump_bytes("security.ima: ", DUMP_PREFIX_NONE,
+ xattr_value, sizeof(*xattr_value));
+ print_hex_dump_bytes("collected: ", DUMP_PREFIX_NONE,
+ (u8 *)&iint->ima_xattr,
+ sizeof iint->ima_xattr);
+ break;
+ }
+ status = INTEGRITY_PASS;
+ break;
+ case EVM_IMA_XATTR_DIGSIG:
+ iint->flags |= IMA_DIGSIG;
+ rc = integrity_digsig_verify(INTEGRITY_KEYRING_IMA,
+ xattr_value->digest, rc - 1,
+ iint->ima_xattr.digest,
+ IMA_DIGEST_SIZE);
+ if (rc == -EOPNOTSUPP) {
+ status = INTEGRITY_UNKNOWN;
+ } else if (rc) {
+ cause = "invalid-signature";
+ status = INTEGRITY_FAIL;
+ } else {
+ status = INTEGRITY_PASS;
+ }
+ break;
+ default:
+ status = INTEGRITY_UNKNOWN;
+ cause = "unknown-ima-data";
+ break;
+ }
+
+out:
+ if (status != INTEGRITY_PASS) {
+ if ((ima_appraise & IMA_APPRAISE_FIX) &&
+ (!xattr_value ||
+ xattr_value->type != EVM_IMA_XATTR_DIGSIG)) {
+ ima_fix_xattr(dentry, iint);
+ status = INTEGRITY_PASS;
+ }
+ integrity_audit_msg(AUDIT_INTEGRITY_DATA, inode, filename,
+ op, cause, rc, 0);
+ } else {
+ iint->flags |= IMA_APPRAISED;
+ }
+ iint->ima_status = status;
+ kfree(xattr_value);
+ return status;
+}
+
+/*
+ * ima_update_xattr - update 'security.ima' hash value
+ */
+void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file)
+{
+ struct dentry *dentry = file->f_dentry;
+ int rc = 0;
+
+ /* do not collect and update hash for digital signatures */
+ if (iint->flags & IMA_DIGSIG)
+ return;
+
+ rc = ima_collect_measurement(iint, file);
+ if (rc < 0)
+ return;
+
+ ima_fix_xattr(dentry, iint);
+}
+
+/**
+ * ima_inode_post_setattr - reflect file metadata changes
+ * @dentry: pointer to the affected dentry
+ *
+ * Changes to a dentry's metadata might result in needing to appraise.
+ *
+ * This function is called from notify_change(), which expects the caller
+ * to lock the inode's i_mutex.
+ */
+void ima_inode_post_setattr(struct dentry *dentry)
+{
+ struct inode *inode = dentry->d_inode;
+ struct integrity_iint_cache *iint;
+ int must_appraise, rc;
+
+ if (!ima_initialized || !ima_appraise || !S_ISREG(inode->i_mode)
+ || !inode->i_op->removexattr)
+ return;
+
+ must_appraise = ima_must_appraise(inode, MAY_ACCESS, POST_SETATTR);
+ iint = integrity_iint_find(inode);
+ if (iint) {
+ if (must_appraise)
+ iint->flags |= IMA_APPRAISE;
+ else
+ iint->flags &= ~(IMA_APPRAISE | IMA_APPRAISED);
+ }
+ if (!must_appraise)
+ rc = inode->i_op->removexattr(dentry, XATTR_NAME_IMA);
+ return;
+}
+
+/*
+ * ima_protect_xattr - protect 'security.ima'
+ *
+ * Ensure that not just anyone can modify or remove 'security.ima'.
+ */
+static int ima_protect_xattr(struct dentry *dentry, const char *xattr_name,
+ const void *xattr_value, size_t xattr_value_len)
+{
+ if (strcmp(xattr_name, XATTR_NAME_IMA) == 0) {
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+ return 1;
+ }
+ return 0;
+}
+
+static void ima_reset_appraise_flags(struct inode *inode)
+{
+ struct integrity_iint_cache *iint;
+
+ if (!ima_initialized || !ima_appraise || !S_ISREG(inode->i_mode))
+ return;
+
+ iint = integrity_iint_find(inode);
+ if (!iint)
+ return;
+
+ iint->flags &= ~IMA_DONE_MASK;
+ return;
+}
+
+int ima_inode_setxattr(struct dentry *dentry, const char *xattr_name,
+ const void *xattr_value, size_t xattr_value_len)
+{
+ int result;
+
+ result = ima_protect_xattr(dentry, xattr_name, xattr_value,
+ xattr_value_len);
+ if (result == 1) {
+ ima_reset_appraise_flags(dentry->d_inode);
+ result = 0;
+ }
+ return result;
+}
+
+int ima_inode_removexattr(struct dentry *dentry, const char *xattr_name)
+{
+ int result;
+
+ result = ima_protect_xattr(dentry, xattr_name, NULL, 0);
+ if (result == 1) {
+ ima_reset_appraise_flags(dentry->d_inode);
+ result = 0;
+ }
+ return result;
+}
diff --git a/security/integrity/ima/ima_crypto.c b/security/integrity/ima/ima_crypto.c
index 9b3ade7..b21ee5b 100644
--- a/security/integrity/ima/ima_crypto.c
+++ b/security/integrity/ima/ima_crypto.c
@@ -48,7 +48,7 @@
struct scatterlist sg[1];
loff_t i_size, offset = 0;
char *rbuf;
- int rc;
+ int rc, read = 0;
rc = init_desc(&desc);
if (rc != 0)
@@ -59,6 +59,10 @@
rc = -ENOMEM;
goto out;
}
+ if (!(file->f_mode & FMODE_READ)) {
+ file->f_mode |= FMODE_READ;
+ read = 1;
+ }
i_size = i_size_read(file->f_dentry->d_inode);
while (offset < i_size) {
int rbuf_len;
@@ -80,6 +84,8 @@
kfree(rbuf);
if (!rc)
rc = crypto_hash_final(&desc, digest);
+ if (read)
+ file->f_mode &= ~FMODE_READ;
out:
crypto_free_hash(desc.tfm);
return rc;
diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
index be82949..73c9a26 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -22,12 +22,19 @@
#include <linux/mount.h>
#include <linux/mman.h>
#include <linux/slab.h>
+#include <linux/xattr.h>
#include <linux/ima.h>
#include "ima.h"
int ima_initialized;
+#ifdef CONFIG_IMA_APPRAISE
+int ima_appraise = IMA_APPRAISE_ENFORCE;
+#else
+int ima_appraise;
+#endif
+
char *ima_hash = "sha1";
static int __init hash_setup(char *str)
{
@@ -52,7 +59,7 @@
struct dentry *dentry = file->f_path.dentry;
struct inode *inode = dentry->d_inode;
fmode_t mode = file->f_mode;
- int rc;
+ int must_measure;
bool send_tomtou = false, send_writers = false;
unsigned char *pathname = NULL, *pathbuf = NULL;
@@ -67,8 +74,8 @@
goto out;
}
- rc = ima_must_measure(inode, MAY_READ, FILE_CHECK);
- if (rc < 0)
+ must_measure = ima_must_measure(inode, MAY_READ, FILE_CHECK);
+ if (!must_measure)
goto out;
if (atomic_read(&inode->i_writecount) > 0)
@@ -100,17 +107,21 @@
}
static void ima_check_last_writer(struct integrity_iint_cache *iint,
- struct inode *inode,
- struct file *file)
+ struct inode *inode, struct file *file)
{
fmode_t mode = file->f_mode;
- mutex_lock(&iint->mutex);
- if (mode & FMODE_WRITE &&
- atomic_read(&inode->i_writecount) == 1 &&
- iint->version != inode->i_version)
- iint->flags &= ~IMA_MEASURED;
- mutex_unlock(&iint->mutex);
+ if (!(mode & FMODE_WRITE))
+ return;
+
+ mutex_lock(&inode->i_mutex);
+ if (atomic_read(&inode->i_writecount) == 1 &&
+ iint->version != inode->i_version) {
+ iint->flags &= ~IMA_DONE_MASK;
+ if (iint->flags & IMA_APPRAISE)
+ ima_update_xattr(iint, file);
+ }
+ mutex_unlock(&inode->i_mutex);
}
/**
@@ -140,29 +151,38 @@
struct inode *inode = file->f_dentry->d_inode;
struct integrity_iint_cache *iint;
unsigned char *pathname = NULL, *pathbuf = NULL;
- int rc = 0;
+ int rc = -ENOMEM, action, must_appraise;
if (!ima_initialized || !S_ISREG(inode->i_mode))
return 0;
- rc = ima_must_measure(inode, mask, function);
- if (rc != 0)
- return rc;
-retry:
- iint = integrity_iint_find(inode);
- if (!iint) {
- rc = integrity_inode_alloc(inode);
- if (!rc || rc == -EEXIST)
- goto retry;
- return rc;
- }
+ /* Determine if in appraise/audit/measurement policy,
+ * returns IMA_MEASURE, IMA_APPRAISE, IMA_AUDIT bitmask. */
+ action = ima_get_action(inode, mask, function);
+ if (!action)
+ return 0;
- mutex_lock(&iint->mutex);
+ must_appraise = action & IMA_APPRAISE;
- rc = iint->flags & IMA_MEASURED ? 1 : 0;
- if (rc != 0)
+ mutex_lock(&inode->i_mutex);
+
+ iint = integrity_inode_get(inode);
+ if (!iint)
goto out;
+ /* Determine if already appraised/measured based on bitmask
+ * (IMA_MEASURE, IMA_MEASURED, IMA_APPRAISE, IMA_APPRAISED,
+ * IMA_AUDIT, IMA_AUDITED) */
+ iint->flags |= action;
+ action &= ~((iint->flags & IMA_DONE_MASK) >> 1);
+
+ /* Nothing to do, just return existing appraised status */
+ if (!action) {
+ if (iint->flags & IMA_APPRAISED)
+ rc = iint->ima_status;
+ goto out;
+ }
+
rc = ima_collect_measurement(iint, file);
if (rc != 0)
goto out;
@@ -177,11 +197,18 @@
pathname = NULL;
}
}
- ima_store_measurement(iint, file, !pathname ? filename : pathname);
+ if (action & IMA_MEASURE)
+ ima_store_measurement(iint, file,
+ !pathname ? filename : pathname);
+ if (action & IMA_APPRAISE)
+ rc = ima_appraise_measurement(iint, file,
+ !pathname ? filename : pathname);
+ if (action & IMA_AUDIT)
+ ima_audit_measurement(iint, !pathname ? filename : pathname);
kfree(pathbuf);
out:
- mutex_unlock(&iint->mutex);
- return rc;
+ mutex_unlock(&inode->i_mutex);
+ return (rc && must_appraise) ? -EACCES : 0;
}
/**
@@ -197,14 +224,14 @@
*/
int ima_file_mmap(struct file *file, unsigned long prot)
{
- int rc;
+ int rc = 0;
if (!file)
return 0;
if (prot & PROT_EXEC)
rc = process_measurement(file, file->f_dentry->d_name.name,
MAY_EXEC, FILE_MMAP);
- return 0;
+ return (ima_appraise & IMA_APPRAISE_ENFORCE) ? rc : 0;
}
/**
@@ -228,7 +255,7 @@
(strcmp(bprm->filename, bprm->interp) == 0) ?
bprm->filename : bprm->interp,
MAY_EXEC, BPRM_CHECK);
- return 0;
+ return (ima_appraise & IMA_APPRAISE_ENFORCE) ? rc : 0;
}
/**
@@ -249,7 +276,7 @@
rc = process_measurement(file, file->f_dentry->d_name.name,
mask & (MAY_READ | MAY_WRITE | MAY_EXEC),
FILE_CHECK);
- return 0;
+ return (ima_appraise & IMA_APPRAISE_ENFORCE) ? rc : 0;
}
EXPORT_SYMBOL_GPL(ima_file_check);
diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index c84df05..c7dacd2 100644
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c
@@ -24,22 +24,29 @@
#define IMA_MASK 0x0002
#define IMA_FSMAGIC 0x0004
#define IMA_UID 0x0008
+#define IMA_FOWNER 0x0010
-enum ima_action { UNKNOWN = -1, DONT_MEASURE = 0, MEASURE };
+#define UNKNOWN 0
+#define MEASURE 0x0001 /* same as IMA_MEASURE */
+#define DONT_MEASURE 0x0002
+#define APPRAISE 0x0004 /* same as IMA_APPRAISE */
+#define DONT_APPRAISE 0x0008
+#define AUDIT 0x0040
#define MAX_LSM_RULES 6
enum lsm_rule_types { LSM_OBJ_USER, LSM_OBJ_ROLE, LSM_OBJ_TYPE,
LSM_SUBJ_USER, LSM_SUBJ_ROLE, LSM_SUBJ_TYPE
};
-struct ima_measure_rule_entry {
+struct ima_rule_entry {
struct list_head list;
- enum ima_action action;
+ int action;
unsigned int flags;
enum ima_hooks func;
int mask;
unsigned long fsmagic;
kuid_t uid;
+ kuid_t fowner;
struct {
void *rule; /* LSM file metadata specific */
int type; /* audit type */
@@ -48,7 +55,7 @@
/*
* Without LSM specific knowledge, the default policy can only be
- * written in terms of .action, .func, .mask, .fsmagic, and .uid
+ * written in terms of .action, .func, .mask, .fsmagic, .uid, and .fowner
*/
/*
@@ -57,7 +64,7 @@
* normal users can easily run the machine out of memory simply building
* and running executables.
*/
-static struct ima_measure_rule_entry default_rules[] = {
+static struct ima_rule_entry default_rules[] = {
{.action = DONT_MEASURE,.fsmagic = PROC_SUPER_MAGIC,.flags = IMA_FSMAGIC},
{.action = DONT_MEASURE,.fsmagic = SYSFS_MAGIC,.flags = IMA_FSMAGIC},
{.action = DONT_MEASURE,.fsmagic = DEBUGFS_MAGIC,.flags = IMA_FSMAGIC},
@@ -75,19 +82,41 @@
.flags = IMA_FUNC | IMA_MASK | IMA_UID},
};
-static LIST_HEAD(measure_default_rules);
-static LIST_HEAD(measure_policy_rules);
-static struct list_head *ima_measure;
+static struct ima_rule_entry default_appraise_rules[] = {
+ {.action = DONT_APPRAISE,.fsmagic = PROC_SUPER_MAGIC,.flags = IMA_FSMAGIC},
+ {.action = DONT_APPRAISE,.fsmagic = SYSFS_MAGIC,.flags = IMA_FSMAGIC},
+ {.action = DONT_APPRAISE,.fsmagic = DEBUGFS_MAGIC,.flags = IMA_FSMAGIC},
+ {.action = DONT_APPRAISE,.fsmagic = TMPFS_MAGIC,.flags = IMA_FSMAGIC},
+ {.action = DONT_APPRAISE,.fsmagic = RAMFS_MAGIC,.flags = IMA_FSMAGIC},
+ {.action = DONT_APPRAISE,.fsmagic = DEVPTS_SUPER_MAGIC,.flags = IMA_FSMAGIC},
+ {.action = DONT_APPRAISE,.fsmagic = BINFMTFS_MAGIC,.flags = IMA_FSMAGIC},
+ {.action = DONT_APPRAISE,.fsmagic = SECURITYFS_MAGIC,.flags = IMA_FSMAGIC},
+ {.action = DONT_APPRAISE,.fsmagic = SELINUX_MAGIC,.flags = IMA_FSMAGIC},
+ {.action = DONT_APPRAISE,.fsmagic = CGROUP_SUPER_MAGIC,.flags = IMA_FSMAGIC},
+ {.action = APPRAISE,.fowner = GLOBAL_ROOT_UID,.flags = IMA_FOWNER},
+};
-static DEFINE_MUTEX(ima_measure_mutex);
+static LIST_HEAD(ima_default_rules);
+static LIST_HEAD(ima_policy_rules);
+static struct list_head *ima_rules;
+
+static DEFINE_MUTEX(ima_rules_mutex);
static bool ima_use_tcb __initdata;
-static int __init default_policy_setup(char *str)
+static int __init default_measure_policy_setup(char *str)
{
ima_use_tcb = 1;
return 1;
}
-__setup("ima_tcb", default_policy_setup);
+__setup("ima_tcb", default_measure_policy_setup);
+
+static bool ima_use_appraise_tcb __initdata;
+static int __init default_appraise_policy_setup(char *str)
+{
+ ima_use_appraise_tcb = 1;
+ return 1;
+}
+__setup("ima_appraise_tcb", default_appraise_policy_setup);
/**
* ima_match_rules - determine whether an inode matches the measure rule.
@@ -98,7 +127,7 @@
*
* Returns true on rule match, false on failure.
*/
-static bool ima_match_rules(struct ima_measure_rule_entry *rule,
+static bool ima_match_rules(struct ima_rule_entry *rule,
struct inode *inode, enum ima_hooks func, int mask)
{
struct task_struct *tsk = current;
@@ -114,6 +143,8 @@
return false;
if ((rule->flags & IMA_UID) && !uid_eq(rule->uid, cred->uid))
return false;
+ if ((rule->flags & IMA_FOWNER) && !uid_eq(rule->fowner, inode->i_uid))
+ return false;
for (i = 0; i < MAX_LSM_RULES; i++) {
int rc = 0;
u32 osid, sid;
@@ -163,39 +194,61 @@
* as elements in the list are never deleted, nor does the list
* change.)
*/
-int ima_match_policy(struct inode *inode, enum ima_hooks func, int mask)
+int ima_match_policy(struct inode *inode, enum ima_hooks func, int mask,
+ int flags)
{
- struct ima_measure_rule_entry *entry;
+ struct ima_rule_entry *entry;
+ int action = 0, actmask = flags | (flags << 1);
- list_for_each_entry(entry, ima_measure, list) {
- bool rc;
+ list_for_each_entry(entry, ima_rules, list) {
- rc = ima_match_rules(entry, inode, func, mask);
- if (rc)
- return entry->action;
+ if (!(entry->action & actmask))
+ continue;
+
+ if (!ima_match_rules(entry, inode, func, mask))
+ continue;
+
+ action |= entry->action & IMA_DO_MASK;
+ if (entry->action & IMA_DO_MASK)
+ actmask &= ~(entry->action | entry->action << 1);
+ else
+ actmask &= ~(entry->action | entry->action >> 1);
+
+ if (!actmask)
+ break;
}
- return 0;
+
+ return action;
}
/**
* ima_init_policy - initialize the default measure rules.
*
- * ima_measure points to either the measure_default_rules or the
- * the new measure_policy_rules.
+ * ima_rules points to either the ima_default_rules or the
+ * the new ima_policy_rules.
*/
void __init ima_init_policy(void)
{
- int i, entries;
+ int i, measure_entries, appraise_entries;
/* if !ima_use_tcb set entries = 0 so we load NO default rules */
- if (ima_use_tcb)
- entries = ARRAY_SIZE(default_rules);
- else
- entries = 0;
+ measure_entries = ima_use_tcb ? ARRAY_SIZE(default_rules) : 0;
+ appraise_entries = ima_use_appraise_tcb ?
+ ARRAY_SIZE(default_appraise_rules) : 0;
+
+ for (i = 0; i < measure_entries + appraise_entries; i++) {
+ if (i < measure_entries)
+ list_add_tail(&default_rules[i].list,
+ &ima_default_rules);
+ else {
+ int j = i - measure_entries;
- for (i = 0; i < entries; i++)
- list_add_tail(&default_rules[i].list, &measure_default_rules);
- ima_measure = &measure_default_rules;
+ list_add_tail(&default_appraise_rules[j].list,
+ &ima_default_rules);
+ }
+ }
+
+ ima_rules = &ima_default_rules;
}
/**
@@ -212,8 +265,8 @@
int result = 1;
int audit_info = 0;
- if (ima_measure == &measure_default_rules) {
- ima_measure = &measure_policy_rules;
+ if (ima_rules == &ima_default_rules) {
+ ima_rules = &ima_policy_rules;
cause = "complete";
result = 0;
}
@@ -224,14 +277,19 @@
enum {
Opt_err = -1,
Opt_measure = 1, Opt_dont_measure,
+ Opt_appraise, Opt_dont_appraise,
+ Opt_audit,
Opt_obj_user, Opt_obj_role, Opt_obj_type,
Opt_subj_user, Opt_subj_role, Opt_subj_type,
- Opt_func, Opt_mask, Opt_fsmagic, Opt_uid
+ Opt_func, Opt_mask, Opt_fsmagic, Opt_uid, Opt_fowner
};
static match_table_t policy_tokens = {
{Opt_measure, "measure"},
{Opt_dont_measure, "dont_measure"},
+ {Opt_appraise, "appraise"},
+ {Opt_dont_appraise, "dont_appraise"},
+ {Opt_audit, "audit"},
{Opt_obj_user, "obj_user=%s"},
{Opt_obj_role, "obj_role=%s"},
{Opt_obj_type, "obj_type=%s"},
@@ -242,10 +300,11 @@
{Opt_mask, "mask=%s"},
{Opt_fsmagic, "fsmagic=%s"},
{Opt_uid, "uid=%s"},
+ {Opt_fowner, "fowner=%s"},
{Opt_err, NULL}
};
-static int ima_lsm_rule_init(struct ima_measure_rule_entry *entry,
+static int ima_lsm_rule_init(struct ima_rule_entry *entry,
char *args, int lsm_rule, int audit_type)
{
int result;
@@ -269,7 +328,7 @@
audit_log_format(ab, " ");
}
-static int ima_parse_rule(char *rule, struct ima_measure_rule_entry *entry)
+static int ima_parse_rule(char *rule, struct ima_rule_entry *entry)
{
struct audit_buffer *ab;
char *p;
@@ -278,6 +337,7 @@
ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_INTEGRITY_RULE);
entry->uid = INVALID_UID;
+ entry->fowner = INVALID_UID;
entry->action = UNKNOWN;
while ((p = strsep(&rule, " \t")) != NULL) {
substring_t args[MAX_OPT_ARGS];
@@ -306,11 +366,35 @@
entry->action = DONT_MEASURE;
break;
+ case Opt_appraise:
+ ima_log_string(ab, "action", "appraise");
+
+ if (entry->action != UNKNOWN)
+ result = -EINVAL;
+
+ entry->action = APPRAISE;
+ break;
+ case Opt_dont_appraise:
+ ima_log_string(ab, "action", "dont_appraise");
+
+ if (entry->action != UNKNOWN)
+ result = -EINVAL;
+
+ entry->action = DONT_APPRAISE;
+ break;
+ case Opt_audit:
+ ima_log_string(ab, "action", "audit");
+
+ if (entry->action != UNKNOWN)
+ result = -EINVAL;
+
+ entry->action = AUDIT;
+ break;
case Opt_func:
ima_log_string(ab, "func", args[0].from);
if (entry->func)
- result = -EINVAL;
+ result = -EINVAL;
if (strcmp(args[0].from, "FILE_CHECK") == 0)
entry->func = FILE_CHECK;
@@ -375,6 +459,23 @@
entry->flags |= IMA_UID;
}
break;
+ case Opt_fowner:
+ ima_log_string(ab, "fowner", args[0].from);
+
+ if (uid_valid(entry->fowner)) {
+ result = -EINVAL;
+ break;
+ }
+
+ result = strict_strtoul(args[0].from, 10, &lnum);
+ if (!result) {
+ entry->fowner = make_kuid(current_user_ns(), (uid_t)lnum);
+ if (!uid_valid(entry->fowner) || (((uid_t)lnum) != lnum))
+ result = -EINVAL;
+ else
+ entry->flags |= IMA_FOWNER;
+ }
+ break;
case Opt_obj_user:
ima_log_string(ab, "obj_user", args[0].from);
result = ima_lsm_rule_init(entry, args[0].from,
@@ -426,7 +527,7 @@
}
/**
- * ima_parse_add_rule - add a rule to measure_policy_rules
+ * ima_parse_add_rule - add a rule to ima_policy_rules
* @rule - ima measurement policy rule
*
* Uses a mutex to protect the policy list from multiple concurrent writers.
@@ -436,12 +537,12 @@
{
const char *op = "update_policy";
char *p;
- struct ima_measure_rule_entry *entry;
+ struct ima_rule_entry *entry;
ssize_t result, len;
int audit_info = 0;
/* Prevent installed policy from changing */
- if (ima_measure != &measure_default_rules) {
+ if (ima_rules != &ima_default_rules) {
integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL,
NULL, op, "already exists",
-EACCES, audit_info);
@@ -474,9 +575,9 @@
return result;
}
- mutex_lock(&ima_measure_mutex);
- list_add_tail(&entry->list, &measure_policy_rules);
- mutex_unlock(&ima_measure_mutex);
+ mutex_lock(&ima_rules_mutex);
+ list_add_tail(&entry->list, &ima_policy_rules);
+ mutex_unlock(&ima_rules_mutex);
return len;
}
@@ -484,12 +585,12 @@
/* ima_delete_rules called to cleanup invalid policy */
void ima_delete_rules(void)
{
- struct ima_measure_rule_entry *entry, *tmp;
+ struct ima_rule_entry *entry, *tmp;
- mutex_lock(&ima_measure_mutex);
- list_for_each_entry_safe(entry, tmp, &measure_policy_rules, list) {
+ mutex_lock(&ima_rules_mutex);
+ list_for_each_entry_safe(entry, tmp, &ima_policy_rules, list) {
list_del(&entry->list);
kfree(entry);
}
- mutex_unlock(&ima_measure_mutex);
+ mutex_unlock(&ima_rules_mutex);
}
diff --git a/security/integrity/integrity.h b/security/integrity/integrity.h
index 7a25ece..e9db763 100644
--- a/security/integrity/integrity.h
+++ b/security/integrity/integrity.h
@@ -15,8 +15,22 @@
#include <linux/integrity.h>
#include <crypto/sha.h>
+/* iint action cache flags */
+#define IMA_MEASURE 0x0001
+#define IMA_MEASURED 0x0002
+#define IMA_APPRAISE 0x0004
+#define IMA_APPRAISED 0x0008
+/*#define IMA_COLLECT 0x0010 do not use this flag */
+#define IMA_COLLECTED 0x0020
+#define IMA_AUDIT 0x0040
+#define IMA_AUDITED 0x0080
+
/* iint cache flags */
-#define IMA_MEASURED 0x01
+#define IMA_DIGSIG 0x0100
+
+#define IMA_DO_MASK (IMA_MEASURE | IMA_APPRAISE | IMA_AUDIT)
+#define IMA_DONE_MASK (IMA_MEASURED | IMA_APPRAISED | IMA_AUDITED \
+ | IMA_COLLECTED)
enum evm_ima_xattr_type {
IMA_XATTR_DIGEST = 0x01,
@@ -34,9 +48,9 @@
struct rb_node rb_node; /* rooted in integrity_iint_tree */
struct inode *inode; /* back pointer to inode in question */
u64 version; /* track inode changes */
- unsigned char flags;
- u8 digest[SHA1_DIGEST_SIZE];
- struct mutex mutex; /* protects: version, flags, digest */
+ unsigned short flags;
+ struct evm_ima_xattr_data ima_xattr;
+ enum integrity_status ima_status;
enum integrity_status evm_status;
};