[PATCH 2/6] security/keys/encrypted: Clean up request_trusted_key()

From: Dan Williams
Date: Tue Mar 19 2019 - 02:19:16 EST


Now that the trusted key type is looked up by name rather than direct
symbol there is no need to play games with detecting the build
configuration. Make request_trusted_key() a static facility internal to
the encrypted-keys implementation.

Suggested-by: James Bottomley <jejb@xxxxxxxxxxxxx>
Cc: Mimi Zohar <zohar@xxxxxxxxxxxxx>
Cc: David Howells <dhowells@xxxxxxxxxx>
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
---
include/linux/key.h | 1
security/keys/encrypted-keys/Makefile | 3 -
security/keys/encrypted-keys/encrypted.c | 32 +++++++++++++
security/keys/encrypted-keys/encrypted.h | 12 -----
security/keys/encrypted-keys/masterkey_trusted.c | 55 ----------------------
security/keys/internal.h | 2 -
security/keys/key.c | 1
7 files changed, 34 insertions(+), 72 deletions(-)
delete mode 100644 security/keys/encrypted-keys/masterkey_trusted.c

diff --git a/include/linux/key.h b/include/linux/key.h
index 7099985e35a9..e7bfd037d26f 100644
--- a/include/linux/key.h
+++ b/include/linux/key.h
@@ -270,6 +270,7 @@ static inline void key_ref_put(key_ref_t key_ref)
key_put(key_ref_to_ptr(key_ref));
}

+extern struct key_type *key_type_lookup(const char *type);
extern struct key *request_key(struct key_type *type,
const char *description,
const char *callout_info);
diff --git a/security/keys/encrypted-keys/Makefile b/security/keys/encrypted-keys/Makefile
index 7a44dce6f69d..d42487bb3d8a 100644
--- a/security/keys/encrypted-keys/Makefile
+++ b/security/keys/encrypted-keys/Makefile
@@ -6,6 +6,3 @@
obj-$(CONFIG_ENCRYPTED_KEYS) += encrypted-keys.o

encrypted-keys-y := encrypted.o ecryptfs_format.o
-masterkey-$(CONFIG_TRUSTED_KEYS) := masterkey_trusted.o
-masterkey-$(CONFIG_TRUSTED_KEYS)-$(CONFIG_ENCRYPTED_KEYS) := masterkey_trusted.o
-encrypted-keys-y += $(masterkey-y) $(masterkey-m-m)
diff --git a/security/keys/encrypted-keys/encrypted.c b/security/keys/encrypted-keys/encrypted.c
index 347108f660a1..06925d3b30c9 100644
--- a/security/keys/encrypted-keys/encrypted.c
+++ b/security/keys/encrypted-keys/encrypted.c
@@ -423,6 +423,37 @@ static struct skcipher_request *init_skcipher_req(const u8 *key,
return req;
}

+/*
+ * 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,
+ const u8 **master_key, size_t *master_keylen)
+{
+ struct trusted_key_payload *tpayload;
+ struct key_type *type;
+ struct key *tkey;
+
+ type = key_type_lookup("trusted");
+ if (IS_ERR(type)) {
+ tkey = (struct key *)type;
+ goto error;
+ }
+ tkey = request_key(type, trusted_desc, NULL);
+ if (IS_ERR(tkey))
+ goto error;
+
+ down_read(&tkey->sem);
+ tpayload = tkey->payload.data[0];
+ *master_key = tpayload->key;
+ *master_keylen = tpayload->key_len;
+error:
+ return tkey;
+}
+
static struct key *request_master_key(struct encrypted_key_payload *epayload,
const u8 **master_key, size_t *master_keylen)
{
@@ -1025,3 +1056,4 @@ late_initcall(init_encrypted);
module_exit(cleanup_encrypted);

MODULE_LICENSE("GPL");
+MODULE_SOFTDEP("pre: trusted");
diff --git a/security/keys/encrypted-keys/encrypted.h b/security/keys/encrypted-keys/encrypted.h
index 1809995db452..0ae67824a24a 100644
--- a/security/keys/encrypted-keys/encrypted.h
+++ b/security/keys/encrypted-keys/encrypted.h
@@ -3,18 +3,6 @@
#define __ENCRYPTED_KEY_H

#define ENCRYPTED_DEBUG 0
-#if defined(CONFIG_TRUSTED_KEYS) || \
- (defined(CONFIG_TRUSTED_KEYS_MODULE) && defined(CONFIG_ENCRYPTED_KEYS_MODULE))
-extern struct key *request_trusted_key(const char *trusted_desc,
- const u8 **master_key, size_t *master_keylen);
-#else
-static inline struct key *request_trusted_key(const char *trusted_desc,
- const 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
deleted file mode 100644
index 7560aea6438d..000000000000
--- a/security/keys/encrypted-keys/masterkey_trusted.c
+++ /dev/null
@@ -1,55 +0,0 @@
-/*
- * Copyright (C) 2010 IBM Corporation
- * Copyright (C) 2010 Politecnico di Torino, Italy
- * TORSEC group -- http://security.polito.it
- *
- * Authors:
- * Mimi Zohar <zohar@xxxxxxxxxx>
- * Roberto Sassu <roberto.sassu@xxxxxxxxx>
- *
- * 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.rst
- */
-
-#include <linux/uaccess.h>
-#include <linux/err.h>
-#include <keys/trusted-type.h>
-#include <keys/encrypted-type.h>
-#include "encrypted.h"
-#include "../internal.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,
- const u8 **master_key, size_t *master_keylen)
-{
- struct trusted_key_payload *tpayload;
- struct key_type *type;
- struct key *tkey;
-
- type = key_type_lookup("trusted");
- if (IS_ERR(type)) {
- tkey = (struct key *)type;
- goto error;
- }
- tkey = request_key(type, trusted_desc, NULL);
- if (IS_ERR(tkey))
- goto error;
-
- down_read(&tkey->sem);
- tpayload = tkey->payload.data[0];
- *master_key = tpayload->key;
- *master_keylen = tpayload->key_len;
-error:
- return tkey;
-}
-
-MODULE_SOFTDEP("pre: trusted");
diff --git a/security/keys/internal.h b/security/keys/internal.h
index 8f533c81aa8d..ea2eb78459bf 100644
--- a/security/keys/internal.h
+++ b/security/keys/internal.h
@@ -89,8 +89,6 @@ extern spinlock_t key_serial_lock;
extern struct mutex key_construction_mutex;
extern wait_queue_head_t request_key_conswq;

-
-extern struct key_type *key_type_lookup(const char *type);
extern void key_type_put(struct key_type *ktype);

extern int __key_link_begin(struct key *keyring,
diff --git a/security/keys/key.c b/security/keys/key.c
index 696f1c092c50..9045b62afb04 100644
--- a/security/keys/key.c
+++ b/security/keys/key.c
@@ -706,6 +706,7 @@ struct key_type *key_type_lookup(const char *type)
found_kernel_type:
return ktype;
}
+EXPORT_SYMBOL_GPL(key_type_lookup);

void key_set_timeout(struct key *key, unsigned timeout)
{