encrypted-keys: remove trusted-keys dependency

Encrypted keys are decrypted/encrypted using either a trusted-key or,
for those systems without a TPM, a user-defined key.  This patch
removes the trusted-keys and TCG_TPM dependencies.

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>

5 files changed, 67 insertions, 28 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/keys/encrypted-keys/Makefile b/security/keys/encrypted-keys/Makefile
index cbd3f8de37bb..6bc7a86d1027 100644
--- a/security/keys/encrypted-keys/Makefile
+++ b/security/keys/encrypted-keys/Makefile
@@ -3,3 +3,4 @@
 #
 
 obj-$(CONFIG_ENCRYPTED_KEYS) += encrypted.o ecryptfs_format.o
+obj-$(CONFIG_TRUSTED_KEYS) += masterkey_trusted.o
diff --git a/security/keys/encrypted-keys/encrypted.c b/security/keys/encrypted-keys/encrypted.c
index e7eca9ec4c65..3f577954b85a 100644
--- a/security/keys/encrypted-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-keys/encrypted.h b/security/keys/encrypted-keys/encrypted.h
index cef5e2f2b7d1..b6ade8945250 100644
--- a/security/keys/encrypted-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;
+}