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authorJames Morris <jmorris@namei.org>2011-09-15 09:53:38 +1000
committerJames Morris <jmorris@namei.org>2011-09-15 09:53:38 +1000
commit8de6ac7f58a22fdab399fbe97763e465ea49c735 (patch)
tree46104451c69f5270fcc11137aecff012a2ecf612 /security
parent843d183cdd816549b73e6bd3ae07f64adddf714b (diff)
parentfb788d8b981fa55603873416882f8dcf835e7924 (diff)
downloadlinux-8de6ac7f58a22fdab399fbe97763e465ea49c735.tar.bz2
Merge branch 'next-evm' of git://github.com/mzohar/linux-evm into next
Diffstat (limited to 'security')
-rw-r--r--security/Kconfig4
-rw-r--r--security/integrity/evm/Kconfig3
-rw-r--r--security/integrity/evm/Makefile1
-rw-r--r--security/integrity/evm/evm_main.c102
-rw-r--r--security/integrity/evm/evm_posix_acl.c26
-rw-r--r--security/integrity/iint.c1
-rw-r--r--security/keys/Makefile2
-rw-r--r--security/keys/encrypted-keys/Makefile6
-rw-r--r--security/keys/encrypted-keys/ecryptfs_format.c (renamed from security/keys/ecryptfs_format.c)0
-rw-r--r--security/keys/encrypted-keys/ecryptfs_format.h (renamed from security/keys/ecryptfs_format.h)0
-rw-r--r--security/keys/encrypted-keys/encrypted.c (renamed from security/keys/encrypted.c)35
-rw-r--r--security/keys/encrypted-keys/encrypted.h (renamed from security/keys/encrypted.h)11
-rw-r--r--security/keys/encrypted-keys/masterkey_trusted.c44
-rw-r--r--security/security.c4
14 files changed, 155 insertions, 84 deletions
diff --git a/security/Kconfig b/security/Kconfig
index 22847a889081..51bd5a0b69ae 100644
--- a/security/Kconfig
+++ b/security/Kconfig
@@ -38,7 +38,9 @@ config TRUSTED_KEYS
config ENCRYPTED_KEYS
tristate "ENCRYPTED KEYS"
- depends on KEYS && TRUSTED_KEYS
+ depends on KEYS
+ select CRYPTO
+ select CRYPTO_HMAC
select CRYPTO_AES
select CRYPTO_CBC
select CRYPTO_SHA256
diff --git a/security/integrity/evm/Kconfig b/security/integrity/evm/Kconfig
index 884617d4aad0..afbb59dd262d 100644
--- a/security/integrity/evm/Kconfig
+++ b/security/integrity/evm/Kconfig
@@ -1,11 +1,10 @@
config EVM
boolean "EVM support"
- depends on SECURITY && KEYS && TCG_TPM
+ depends on SECURITY && KEYS && (TRUSTED_KEYS=y || TRUSTED_KEYS=n)
select CRYPTO_HMAC
select CRYPTO_MD5
select CRYPTO_SHA1
select ENCRYPTED_KEYS
- select TRUSTED_KEYS
default n
help
EVM protects a file's security extended attributes against
diff --git a/security/integrity/evm/Makefile b/security/integrity/evm/Makefile
index 0787d262b9e3..7393c415a066 100644
--- a/security/integrity/evm/Makefile
+++ b/security/integrity/evm/Makefile
@@ -4,3 +4,4 @@
obj-$(CONFIG_EVM) += evm.o
evm-y := evm_main.o evm_crypto.o evm_secfs.o
+evm-$(CONFIG_FS_POSIX_ACL) += evm_posix_acl.o
diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c
index f0127e536f84..92d3d99a9f7b 100644
--- a/security/integrity/evm/evm_main.c
+++ b/security/integrity/evm/evm_main.c
@@ -66,7 +66,7 @@ static enum integrity_status evm_verify_hmac(struct dentry *dentry,
struct integrity_iint_cache *iint)
{
struct evm_ima_xattr_data xattr_data;
- enum integrity_status evm_status;
+ enum integrity_status evm_status = INTEGRITY_PASS;
int rc;
if (iint && iint->evm_status == INTEGRITY_PASS)
@@ -76,25 +76,18 @@ static enum integrity_status evm_verify_hmac(struct dentry *dentry,
rc = evm_calc_hmac(dentry, xattr_name, xattr_value,
xattr_value_len, xattr_data.digest);
- if (rc < 0)
- goto err_out;
+ if (rc < 0) {
+ evm_status = (rc == -ENODATA)
+ ? INTEGRITY_NOXATTRS : INTEGRITY_FAIL;
+ goto out;
+ }
xattr_data.type = EVM_XATTR_HMAC;
rc = vfs_xattr_cmp(dentry, XATTR_NAME_EVM, (u8 *)&xattr_data,
sizeof xattr_data, GFP_NOFS);
if (rc < 0)
- goto err_out;
- evm_status = INTEGRITY_PASS;
- goto out;
-
-err_out:
- switch (rc) {
- case -ENODATA: /* file not labelled */
- evm_status = INTEGRITY_NOLABEL;
- break;
- default:
- evm_status = INTEGRITY_FAIL;
- }
+ evm_status = (rc == -ENODATA)
+ ? INTEGRITY_NOLABEL : INTEGRITY_FAIL;
out:
if (iint)
iint->evm_status = evm_status;
@@ -159,21 +152,6 @@ enum integrity_status evm_verifyxattr(struct dentry *dentry,
EXPORT_SYMBOL_GPL(evm_verifyxattr);
/*
- * evm_protect_xattr - protect the EVM extended attribute
- *
- * Prevent security.evm from being modified or removed.
- */
-static int evm_protect_xattr(struct dentry *dentry, const char *xattr_name,
- const void *xattr_value, size_t xattr_value_len)
-{
- if (strcmp(xattr_name, XATTR_NAME_EVM) == 0) {
- if (!capable(CAP_SYS_ADMIN))
- return -EPERM;
- }
- return 0;
-}
-
-/*
* evm_verify_current_integrity - verify the dentry's metadata integrity
* @dentry: pointer to the affected dentry
*
@@ -189,6 +167,39 @@ static enum integrity_status evm_verify_current_integrity(struct dentry *dentry)
return evm_verify_hmac(dentry, NULL, NULL, 0, NULL);
}
+/*
+ * evm_protect_xattr - protect the EVM extended attribute
+ *
+ * Prevent security.evm from being modified or removed without the
+ * necessary permissions or when the existing value is invalid.
+ *
+ * The posix xattr acls are 'system' prefixed, which normally would not
+ * affect security.evm. An interesting side affect of writing posix xattr
+ * acls is their modifying of the i_mode, which is included in security.evm.
+ * For posix xattr acls only, permit security.evm, even if it currently
+ * doesn't exist, to be updated.
+ */
+static int evm_protect_xattr(struct dentry *dentry, const char *xattr_name,
+ const void *xattr_value, size_t xattr_value_len)
+{
+ enum integrity_status evm_status;
+
+ if (strcmp(xattr_name, XATTR_NAME_EVM) == 0) {
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+ } else if (!evm_protected_xattr(xattr_name)) {
+ if (!posix_xattr_acl(xattr_name))
+ return 0;
+ evm_status = evm_verify_current_integrity(dentry);
+ if ((evm_status == INTEGRITY_PASS) ||
+ (evm_status == INTEGRITY_NOXATTRS))
+ return 0;
+ return -EPERM;
+ }
+ evm_status = evm_verify_current_integrity(dentry);
+ return evm_status == INTEGRITY_PASS ? 0 : -EPERM;
+}
+
/**
* evm_inode_setxattr - protect the EVM extended attribute
* @dentry: pointer to the affected dentry
@@ -202,16 +213,8 @@ static enum integrity_status evm_verify_current_integrity(struct dentry *dentry)
int evm_inode_setxattr(struct dentry *dentry, const char *xattr_name,
const void *xattr_value, size_t xattr_value_len)
{
-
- enum integrity_status evm_status;
- int ret;
-
- ret = evm_protect_xattr(dentry, xattr_name, xattr_value,
- xattr_value_len);
- if (ret)
- return ret;
- evm_status = evm_verify_current_integrity(dentry);
- return evm_status == INTEGRITY_PASS ? 0 : -EPERM;
+ return evm_protect_xattr(dentry, xattr_name, xattr_value,
+ xattr_value_len);
}
/**
@@ -224,14 +227,7 @@ int evm_inode_setxattr(struct dentry *dentry, const char *xattr_name,
*/
int evm_inode_removexattr(struct dentry *dentry, const char *xattr_name)
{
- enum integrity_status evm_status;
- int ret;
-
- ret = evm_protect_xattr(dentry, xattr_name, NULL, 0);
- if (ret)
- return ret;
- evm_status = evm_verify_current_integrity(dentry);
- return evm_status == INTEGRITY_PASS ? 0 : -EPERM;
+ return evm_protect_xattr(dentry, xattr_name, NULL, 0);
}
/**
@@ -250,7 +246,8 @@ int evm_inode_removexattr(struct dentry *dentry, const char *xattr_name)
void evm_inode_post_setxattr(struct dentry *dentry, const char *xattr_name,
const void *xattr_value, size_t xattr_value_len)
{
- if (!evm_initialized || !evm_protected_xattr(xattr_name))
+ if (!evm_initialized || (!evm_protected_xattr(xattr_name)
+ && !posix_xattr_acl(xattr_name)))
return;
evm_update_evmxattr(dentry, xattr_name, xattr_value, xattr_value_len);
@@ -286,10 +283,13 @@ int evm_inode_setattr(struct dentry *dentry, struct iattr *attr)
unsigned int ia_valid = attr->ia_valid;
enum integrity_status evm_status;
- if (ia_valid & ~(ATTR_MODE | ATTR_UID | ATTR_GID))
+ if (!(ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID)))
return 0;
evm_status = evm_verify_current_integrity(dentry);
- return evm_status == INTEGRITY_PASS ? 0 : -EPERM;
+ if ((evm_status == INTEGRITY_PASS) ||
+ (evm_status == INTEGRITY_NOXATTRS))
+ return 0;
+ return -EPERM;
}
/**
diff --git a/security/integrity/evm/evm_posix_acl.c b/security/integrity/evm/evm_posix_acl.c
new file mode 100644
index 000000000000..b1753e98bf9a
--- /dev/null
+++ b/security/integrity/evm/evm_posix_acl.c
@@ -0,0 +1,26 @@
+/*
+ * Copyright (C) 2011 IBM Corporation
+ *
+ * Author:
+ * Mimi Zohar <zohar@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 2 of the License.
+ */
+
+#include <linux/module.h>
+#include <linux/xattr.h>
+
+int posix_xattr_acl(char *xattr)
+{
+ int xattr_len = strlen(xattr);
+
+ if ((strlen(XATTR_NAME_POSIX_ACL_ACCESS) == xattr_len)
+ && (strncmp(XATTR_NAME_POSIX_ACL_ACCESS, xattr, xattr_len) == 0))
+ return 1;
+ if ((strlen(XATTR_NAME_POSIX_ACL_DEFAULT) == xattr_len)
+ && (strncmp(XATTR_NAME_POSIX_ACL_DEFAULT, xattr, xattr_len) == 0))
+ return 1;
+ return 0;
+}
diff --git a/security/integrity/iint.c b/security/integrity/iint.c
index 0a23e075e1d2..399641c3e846 100644
--- a/security/integrity/iint.c
+++ b/security/integrity/iint.c
@@ -74,6 +74,7 @@ static void iint_free(struct integrity_iint_cache *iint)
{
iint->version = 0;
iint->flags = 0UL;
+ iint->evm_status = INTEGRITY_UNKNOWN;
kmem_cache_free(iint_cache, iint);
}
diff --git a/security/keys/Makefile b/security/keys/Makefile
index b34cc6ee6900..a56f1ffdc64d 100644
--- a/security/keys/Makefile
+++ b/security/keys/Makefile
@@ -14,7 +14,7 @@ obj-y := \
user_defined.o
obj-$(CONFIG_TRUSTED_KEYS) += trusted.o
-obj-$(CONFIG_ENCRYPTED_KEYS) += ecryptfs_format.o encrypted.o
+obj-$(CONFIG_ENCRYPTED_KEYS) += encrypted-keys/
obj-$(CONFIG_KEYS_COMPAT) += compat.o
obj-$(CONFIG_PROC_FS) += proc.o
obj-$(CONFIG_SYSCTL) += sysctl.o
diff --git a/security/keys/encrypted-keys/Makefile b/security/keys/encrypted-keys/Makefile
new file mode 100644
index 000000000000..6bc7a86d1027
--- /dev/null
+++ b/security/keys/encrypted-keys/Makefile
@@ -0,0 +1,6 @@
+#
+# Makefile for encrypted keys
+#
+
+obj-$(CONFIG_ENCRYPTED_KEYS) += encrypted.o ecryptfs_format.o
+obj-$(CONFIG_TRUSTED_KEYS) += masterkey_trusted.o
diff --git a/security/keys/ecryptfs_format.c b/security/keys/encrypted-keys/ecryptfs_format.c
index 6daa3b6ff9ed..6daa3b6ff9ed 100644
--- a/security/keys/ecryptfs_format.c
+++ b/security/keys/encrypted-keys/ecryptfs_format.c
diff --git a/security/keys/ecryptfs_format.h b/security/keys/encrypted-keys/ecryptfs_format.h
index 40294de238bb..40294de238bb 100644
--- a/security/keys/ecryptfs_format.h
+++ b/security/keys/encrypted-keys/ecryptfs_format.h
diff --git a/security/keys/encrypted.c b/security/keys/encrypted-keys/encrypted.c
index e7eca9ec4c65..3f577954b85a 100644
--- a/security/keys/encrypted.c
+++ b/security/keys/encrypted-keys/encrypted.c
@@ -299,31 +299,6 @@ out:
}
/*
- * request_trusted_key - request the trusted key
- *
- * Trusted keys are sealed to PCRs and other metadata. Although userspace
- * manages both trusted/encrypted key-types, like the encrypted key type
- * data, trusted key type data is not visible decrypted from userspace.
- */
-static struct key *request_trusted_key(const char *trusted_desc,
- u8 **master_key, size_t *master_keylen)
-{
- struct trusted_key_payload *tpayload;
- struct key *tkey;
-
- tkey = request_key(&key_type_trusted, trusted_desc, NULL);
- if (IS_ERR(tkey))
- goto error;
-
- down_read(&tkey->sem);
- tpayload = rcu_dereference(tkey->payload.data);
- *master_key = tpayload->key;
- *master_keylen = tpayload->key_len;
-error:
- return tkey;
-}
-
-/*
* request_user_key - request the user key
*
* Use a user provided key to encrypt/decrypt an encrypted-key.
@@ -469,8 +444,14 @@ static struct key *request_master_key(struct encrypted_key_payload *epayload,
goto out;
if (IS_ERR(mkey)) {
- pr_info("encrypted_key: key %s not found",
- epayload->master_desc);
+ int ret = PTR_ERR(epayload);
+
+ if (ret == -ENOTSUPP)
+ pr_info("encrypted_key: key %s not supported",
+ epayload->master_desc);
+ else
+ pr_info("encrypted_key: key %s not found",
+ epayload->master_desc);
goto out;
}
diff --git a/security/keys/encrypted.h b/security/keys/encrypted-keys/encrypted.h
index cef5e2f2b7d1..b6ade8945250 100644
--- a/security/keys/encrypted.h
+++ b/security/keys/encrypted-keys/encrypted.h
@@ -2,6 +2,17 @@
#define __ENCRYPTED_KEY_H
#define ENCRYPTED_DEBUG 0
+#ifdef CONFIG_TRUSTED_KEYS
+extern struct key *request_trusted_key(const char *trusted_desc,
+ u8 **master_key, size_t *master_keylen);
+#else
+static inline struct key *request_trusted_key(const char *trusted_desc,
+ u8 **master_key,
+ size_t *master_keylen)
+{
+ return ERR_PTR(-EOPNOTSUPP);
+}
+#endif
#if ENCRYPTED_DEBUG
static inline void dump_master_key(const u8 *master_key, size_t master_keylen)
diff --git a/security/keys/encrypted-keys/masterkey_trusted.c b/security/keys/encrypted-keys/masterkey_trusted.c
new file mode 100644
index 000000000000..a5da5128891b
--- /dev/null
+++ b/security/keys/encrypted-keys/masterkey_trusted.c
@@ -0,0 +1,44 @@
+/*
+ * Copyright (C) 2010 IBM Corporation
+ * Copyright (C) 2010 Politecnico di Torino, Italy
+ * TORSEC group -- http://security.polito.it
+ *
+ * Authors:
+ * Mimi Zohar <zohar@us.ibm.com>
+ * Roberto Sassu <roberto.sassu@polito.it>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 2 of the License.
+ *
+ * See Documentation/security/keys-trusted-encrypted.txt
+ */
+
+#include <linux/uaccess.h>
+#include <linux/module.h>
+#include <keys/trusted-type.h>
+
+/*
+ * request_trusted_key - request the trusted key
+ *
+ * Trusted keys are sealed to PCRs and other metadata. Although userspace
+ * manages both trusted/encrypted key-types, like the encrypted key type
+ * data, trusted key type data is not visible decrypted from userspace.
+ */
+struct key *request_trusted_key(const char *trusted_desc,
+ u8 **master_key, size_t *master_keylen)
+{
+ struct trusted_key_payload *tpayload;
+ struct key *tkey;
+
+ tkey = request_key(&key_type_trusted, trusted_desc, NULL);
+ if (IS_ERR(tkey))
+ goto error;
+
+ down_read(&tkey->sem);
+ tpayload = rcu_dereference(tkey->payload.data);
+ *master_key = tpayload->key;
+ *master_keylen = tpayload->key_len;
+error:
+ return tkey;
+}
diff --git a/security/security.c b/security/security.c
index 9ebda054a333..c1d69875db6c 100644
--- a/security/security.c
+++ b/security/security.c
@@ -348,7 +348,7 @@ int security_inode_init_security(struct inode *inode, struct inode *dir,
int ret;
if (unlikely(IS_PRIVATE(inode)))
- return -EOPNOTSUPP;
+ return 0;
memset(new_xattrs, 0, sizeof new_xattrs);
if (!initxattrs)
@@ -381,7 +381,7 @@ int security_old_inode_init_security(struct inode *inode, struct inode *dir,
void **value, size_t *len)
{
if (unlikely(IS_PRIVATE(inode)))
- return -EOPNOTSUPP;
+ return 0;
return security_ops->inode_init_security(inode, dir, qstr, name, value,
len);
}