summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--include/linux/evm.h11
-rw-r--r--security/integrity/evm/evm.h3
-rw-r--r--security/integrity/evm/evm_crypto.c20
-rw-r--r--security/integrity/evm/evm_main.c38
4 files changed, 72 insertions, 0 deletions
diff --git a/include/linux/evm.h b/include/linux/evm.h
index 33a92471e46..7c10761916a 100644
--- a/include/linux/evm.h
+++ b/include/linux/evm.h
@@ -9,6 +9,7 @@
#define _LINUX_EVM_H
#include <linux/integrity.h>
+#include <linux/xattr.h>
#ifdef CONFIG_EVM
extern enum integrity_status evm_verifyxattr(struct dentry *dentry,
@@ -25,6 +26,9 @@ extern void evm_inode_post_setxattr(struct dentry *dentry,
extern int evm_inode_removexattr(struct dentry *dentry, const char *xattr_name);
extern void evm_inode_post_removexattr(struct dentry *dentry,
const char *xattr_name);
+extern int evm_inode_init_security(struct inode *inode,
+ const struct xattr *xattr_array,
+ struct xattr *evm);
#else
#ifdef CONFIG_INTEGRITY
static inline enum integrity_status evm_verifyxattr(struct dentry *dentry,
@@ -67,5 +71,12 @@ static inline void evm_inode_post_removexattr(struct dentry *dentry,
return;
}
+static inline int evm_inode_init_security(struct inode *inode,
+ const struct xattr *xattr_array,
+ struct xattr *evm)
+{
+ return -EOPNOTSUPP;
+}
+
#endif /* CONFIG_EVM_H */
#endif /* LINUX_EVM_H */
diff --git a/security/integrity/evm/evm.h b/security/integrity/evm/evm.h
index 375dc3e6015..a45d0d630a3 100644
--- a/security/integrity/evm/evm.h
+++ b/security/integrity/evm/evm.h
@@ -12,6 +12,7 @@
* File: evm.h
*
*/
+#include <linux/xattr.h>
#include <linux/security.h>
#include "../integrity.h"
@@ -29,5 +30,7 @@ extern int evm_update_evmxattr(struct dentry *dentry,
extern int evm_calc_hmac(struct dentry *dentry, const char *req_xattr_name,
const char *req_xattr_value,
size_t req_xattr_value_len, char *digest);
+extern int evm_init_hmac(struct inode *inode, const struct xattr *xattr,
+ char *hmac_val);
extern int evm_init_secfs(void);
extern void evm_cleanup_secfs(void);
diff --git a/security/integrity/evm/evm_crypto.c b/security/integrity/evm/evm_crypto.c
index c631b99bda9..c9902bddcb9 100644
--- a/security/integrity/evm/evm_crypto.c
+++ b/security/integrity/evm/evm_crypto.c
@@ -157,6 +157,26 @@ int evm_update_evmxattr(struct dentry *dentry, const char *xattr_name,
return rc;
}
+int evm_init_hmac(struct inode *inode, const struct xattr *lsm_xattr,
+ char *hmac_val)
+{
+ struct hash_desc desc;
+ struct scatterlist sg[1];
+ int error;
+
+ error = init_desc(&desc);
+ if (error != 0) {
+ printk(KERN_INFO "init_desc failed\n");
+ return error;
+ }
+
+ sg_init_one(sg, lsm_xattr->value, lsm_xattr->value_len);
+ crypto_hash_update(&desc, sg, lsm_xattr->value_len);
+ hmac_add_misc(&desc, inode, hmac_val);
+ crypto_free_hash(desc.tfm);
+ return 0;
+}
+
/*
* Get the key from the TPM for the SHA1-HMAC
*/
diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c
index 1746c3669c6..23486355f44 100644
--- a/security/integrity/evm/evm_main.c
+++ b/security/integrity/evm/evm_main.c
@@ -98,6 +98,12 @@ static int evm_protected_xattr(const char *req_xattr_name)
found = 1;
break;
}
+ if (strncmp(req_xattr_name,
+ *xattrname + XATTR_SECURITY_PREFIX_LEN,
+ strlen(req_xattr_name)) == 0) {
+ found = 1;
+ break;
+ }
}
return found;
}
@@ -245,6 +251,38 @@ void evm_inode_post_setattr(struct dentry *dentry, int ia_valid)
return;
}
+/*
+ * evm_inode_init_security - initializes security.evm
+ */
+int evm_inode_init_security(struct inode *inode,
+ const struct xattr *lsm_xattr,
+ struct xattr *evm_xattr)
+{
+ struct evm_ima_xattr_data *xattr_data;
+ int rc;
+
+ if (!evm_initialized || !evm_protected_xattr(lsm_xattr->name))
+ return -EOPNOTSUPP;
+
+ xattr_data = kzalloc(sizeof(*xattr_data), GFP_NOFS);
+ if (!xattr_data)
+ return -ENOMEM;
+
+ xattr_data->type = EVM_XATTR_HMAC;
+ rc = evm_init_hmac(inode, lsm_xattr, xattr_data->digest);
+ if (rc < 0)
+ goto out;
+
+ evm_xattr->value = xattr_data;
+ evm_xattr->value_len = sizeof(*xattr_data);
+ evm_xattr->name = kstrdup(XATTR_EVM_SUFFIX, GFP_NOFS);
+ return 0;
+out:
+ kfree(xattr_data);
+ return rc;
+}
+EXPORT_SYMBOL_GPL(evm_inode_init_security);
+
static struct crypto_hash *tfm_hmac; /* preload crypto alg */
static int __init init_evm(void)
{