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* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6: (30 commits)
  MAINTAINERS: Add tomoyo-dev-en ML.
  SELinux: define permissions for DCB netlink messages
  encrypted-keys: style and other cleanup
  encrypted-keys: verify datablob size before converting to binary
  trusted-keys: kzalloc and other cleanup
  trusted-keys: additional TSS return code and other error handling
  syslog: check cap_syslog when dmesg_restrict
  Smack: Transmute labels on specified directories
  selinux: cache sidtab_context_to_sid results
  SELinux: do not compute transition labels on mountpoint labeled filesystems
  This patch adds a new security attribute to Smack called SMACK64EXEC. It defines label that is used while task is running.
  SELinux: merge policydb_index_classes and policydb_index_others
  selinux: convert part of the sym_val_to_name array to use flex_array
  selinux: convert type_val_to_struct to flex_array
  flex_array: fix flex_array_put_ptr macro to be valid C
  SELinux: do not set automatic i_ino in selinuxfs
  selinux: rework security_netlbl_secattr_to_sid
  SELinux: standardize return code handling in selinuxfs.c
  SELinux: standardize return code handling in selinuxfs.c
  SELinux: standardize return code handling in policydb.c
  ...
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Linus Torvalds committed Jan 10, 2011
2 parents a089488 + aeda4ac commit e0e736f
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145 changes: 145 additions & 0 deletions Documentation/keys-trusted-encrypted.txt
Original file line number Diff line number Diff line change
@@ -0,0 +1,145 @@
Trusted and Encrypted Keys

Trusted and Encrypted Keys are two new key types added to the existing kernel
key ring service. Both of these new types are variable length symmetic keys,
and in both cases all keys are created in the kernel, and user space sees,
stores, and loads only encrypted blobs. Trusted Keys require the availability
of a Trusted Platform Module (TPM) chip for greater security, while Encrypted
Keys can be used on any system. All user level blobs, are displayed and loaded
in hex ascii for convenience, and are integrity verified.

Trusted Keys use a TPM both to generate and to seal the keys. Keys are sealed
under a 2048 bit RSA key in the TPM, and optionally sealed to specified PCR
(integrity measurement) values, and only unsealed by the TPM, if PCRs and blob
integrity verifications match. A loaded Trusted Key can be updated with new
(future) PCR values, so keys are easily migrated to new pcr values, such as
when the kernel and initramfs are updated. The same key can have many saved
blobs under different PCR values, so multiple boots are easily supported.

By default, trusted keys are sealed under the SRK, which has the default
authorization value (20 zeros). This can be set at takeownership time with the
trouser's utility: "tpm_takeownership -u -z".

Usage:
keyctl add trusted name "new keylen [options]" ring
keyctl add trusted name "load hex_blob [pcrlock=pcrnum]" ring
keyctl update key "update [options]"
keyctl print keyid

options:
keyhandle= ascii hex value of sealing key default 0x40000000 (SRK)
keyauth= ascii hex auth for sealing key default 0x00...i
(40 ascii zeros)
blobauth= ascii hex auth for sealed data default 0x00...
(40 ascii zeros)
blobauth= ascii hex auth for sealed data default 0x00...
(40 ascii zeros)
pcrinfo= ascii hex of PCR_INFO or PCR_INFO_LONG (no default)
pcrlock= pcr number to be extended to "lock" blob
migratable= 0|1 indicating permission to reseal to new PCR values,
default 1 (resealing allowed)

"keyctl print" returns an ascii hex copy of the sealed key, which is in standard
TPM_STORED_DATA format. The key length for new keys are always in bytes.
Trusted Keys can be 32 - 128 bytes (256 - 1024 bits), the upper limit is to fit
within the 2048 bit SRK (RSA) keylength, with all necessary structure/padding.

Encrypted keys do not depend on a TPM, and are faster, as they use AES for
encryption/decryption. New keys are created from kernel generated random
numbers, and are encrypted/decrypted using a specified 'master' key. The
'master' key can either be a trusted-key or user-key type. The main
disadvantage of encrypted keys is that if they are not rooted in a trusted key,
they are only as secure as the user key encrypting them. The master user key
should therefore be loaded in as secure a way as possible, preferably early in
boot.

Usage:
keyctl add encrypted name "new key-type:master-key-name keylen" ring
keyctl add encrypted name "load hex_blob" ring
keyctl update keyid "update key-type:master-key-name"

where 'key-type' is either 'trusted' or 'user'.

Examples of trusted and encrypted key usage:

Create and save a trusted key named "kmk" of length 32 bytes:

$ keyctl add trusted kmk "new 32" @u
440502848

$ keyctl show
Session Keyring
-3 --alswrv 500 500 keyring: _ses
97833714 --alswrv 500 -1 \_ keyring: _uid.500
440502848 --alswrv 500 500 \_ trusted: kmk

$ keyctl print 440502848
0101000000000000000001005d01b7e3f4a6be5709930f3b70a743cbb42e0cc95e18e915
3f60da455bbf1144ad12e4f92b452f966929f6105fd29ca28e4d4d5a031d068478bacb0b
27351119f822911b0a11ba3d3498ba6a32e50dac7f32894dd890eb9ad578e4e292c83722
a52e56a097e6a68b3f56f7a52ece0cdccba1eb62cad7d817f6dc58898b3ac15f36026fec
d568bd4a706cb60bb37be6d8f1240661199d640b66fb0fe3b079f97f450b9ef9c22c6d5d
dd379f0facd1cd020281dfa3c70ba21a3fa6fc2471dc6d13ecf8298b946f65345faa5ef0
f1f8fff03ad0acb083725535636addb08d73dedb9832da198081e5deae84bfaf0409c22b
e4a8aea2b607ec96931e6f4d4fe563ba

$ keyctl pipe 440502848 > kmk.blob

Load a trusted key from the saved blob:

$ keyctl add trusted kmk "load `cat kmk.blob`" @u
268728824

$ keyctl print 268728824
0101000000000000000001005d01b7e3f4a6be5709930f3b70a743cbb42e0cc95e18e915
3f60da455bbf1144ad12e4f92b452f966929f6105fd29ca28e4d4d5a031d068478bacb0b
27351119f822911b0a11ba3d3498ba6a32e50dac7f32894dd890eb9ad578e4e292c83722
a52e56a097e6a68b3f56f7a52ece0cdccba1eb62cad7d817f6dc58898b3ac15f36026fec
d568bd4a706cb60bb37be6d8f1240661199d640b66fb0fe3b079f97f450b9ef9c22c6d5d
dd379f0facd1cd020281dfa3c70ba21a3fa6fc2471dc6d13ecf8298b946f65345faa5ef0
f1f8fff03ad0acb083725535636addb08d73dedb9832da198081e5deae84bfaf0409c22b
e4a8aea2b607ec96931e6f4d4fe563ba

Reseal a trusted key under new pcr values:

$ keyctl update 268728824 "update pcrinfo=`cat pcr.blob`"
$ keyctl print 268728824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Create and save an encrypted key "evm" using the above trusted key "kmk":

$ keyctl add encrypted evm "new trusted:kmk 32" @u
159771175

$ keyctl print 159771175
trusted:kmk 32 2375725ad57798846a9bbd240de8906f006e66c03af53b1b382dbbc55
be2a44616e4959430436dc4f2a7a9659aa60bb4652aeb2120f149ed197c564e024717c64
5972dcb82ab2dde83376d82b2e3c09ffc

$ keyctl pipe 159771175 > evm.blob

Load an encrypted key "evm" from saved blob:

$ keyctl add encrypted evm "load `cat evm.blob`" @u
831684262

$ keyctl print 831684262
trusted:kmk 32 2375725ad57798846a9bbd240de8906f006e66c03af53b1b382dbbc55
be2a44616e4959430436dc4f2a7a9659aa60bb4652aeb2120f149ed197c564e024717c64
5972dcb82ab2dde83376d82b2e3c09ffc


The initial consumer of trusted keys is EVM, which at boot time needs a high
quality symmetric key for HMAC protection of file metadata. The use of a
trusted key provides strong guarantees that the EVM key has not been
compromised by a user level problem, and when sealed to specific boot PCR
values, protects against boot and offline attacks. Other uses for trusted and
encrypted keys, such as for disk and file encryption are anticipated.
2 changes: 1 addition & 1 deletion Documentation/sysctl/kernel.txt
Original file line number Diff line number Diff line change
Expand Up @@ -219,7 +219,7 @@ dmesg_restrict:
This toggle indicates whether unprivileged users are prevented from using
dmesg(8) to view messages from the kernel's log buffer. When
dmesg_restrict is set to (0) there are no restrictions. When
dmesg_restrict is set set to (1), users must have CAP_SYS_ADMIN to use
dmesg_restrict is set set to (1), users must have CAP_SYSLOG to use
dmesg(8).

The kernel config option CONFIG_SECURITY_DMESG_RESTRICT sets the default
Expand Down
3 changes: 2 additions & 1 deletion MAINTAINERS
Original file line number Diff line number Diff line change
Expand Up @@ -5930,7 +5930,8 @@ F: drivers/net/tlan.*
TOMOYO SECURITY MODULE
M: Kentaro Takeda <takedakn@nttdata.co.jp>
M: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
L: tomoyo-users-en@lists.sourceforge.jp (subscribers-only, for developers and users in English)
L: tomoyo-dev-en@lists.sourceforge.jp (subscribers-only, for developers in English)
L: tomoyo-users-en@lists.sourceforge.jp (subscribers-only, for users in English)
L: tomoyo-dev@lists.sourceforge.jp (subscribers-only, for developers in Japanese)
L: tomoyo-users@lists.sourceforge.jp (subscribers-only, for users in Japanese)
W: http://tomoyo.sourceforge.jp/
Expand Down
20 changes: 18 additions & 2 deletions drivers/char/tpm/tpm.c
Original file line number Diff line number Diff line change
Expand Up @@ -736,7 +736,7 @@ int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf)
if (chip == NULL)
return -ENODEV;
rc = __tpm_pcr_read(chip, pcr_idx, res_buf);
module_put(chip->dev->driver->owner);
tpm_chip_put(chip);
return rc;
}
EXPORT_SYMBOL_GPL(tpm_pcr_read);
Expand Down Expand Up @@ -775,11 +775,27 @@ int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
"attempting extend a PCR value");

module_put(chip->dev->driver->owner);
tpm_chip_put(chip);
return rc;
}
EXPORT_SYMBOL_GPL(tpm_pcr_extend);

int tpm_send(u32 chip_num, void *cmd, size_t buflen)
{
struct tpm_chip *chip;
int rc;

chip = tpm_chip_find_get(chip_num);
if (chip == NULL)
return -ENODEV;

rc = transmit_cmd(chip, cmd, buflen, "attempting tpm_cmd");

tpm_chip_put(chip);
return rc;
}
EXPORT_SYMBOL_GPL(tpm_send);

ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
char *buf)
{
Expand Down
5 changes: 5 additions & 0 deletions drivers/char/tpm/tpm.h
Original file line number Diff line number Diff line change
Expand Up @@ -113,6 +113,11 @@ struct tpm_chip {

#define to_tpm_chip(n) container_of(n, struct tpm_chip, vendor)

static inline void tpm_chip_put(struct tpm_chip *chip)
{
module_put(chip->dev->driver->owner);
}

static inline int tpm_read_index(int base, int index)
{
outb(index, base);
Expand Down
29 changes: 29 additions & 0 deletions include/keys/encrypted-type.h
Original file line number Diff line number Diff line change
@@ -0,0 +1,29 @@
/*
* Copyright (C) 2010 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.
*/

#ifndef _KEYS_ENCRYPTED_TYPE_H
#define _KEYS_ENCRYPTED_TYPE_H

#include <linux/key.h>
#include <linux/rcupdate.h>

struct encrypted_key_payload {
struct rcu_head rcu;
char *master_desc; /* datablob: master key name */
char *datalen; /* datablob: decrypted key length */
u8 *iv; /* datablob: iv */
u8 *encrypted_data; /* datablob: encrypted data */
unsigned short datablob_len; /* length of datablob */
unsigned short decrypted_datalen; /* decrypted data length */
u8 decrypted_data[0]; /* decrypted data + datablob + hmac */
};

extern struct key_type key_type_encrypted;

#endif /* _KEYS_ENCRYPTED_TYPE_H */
31 changes: 31 additions & 0 deletions include/keys/trusted-type.h
Original file line number Diff line number Diff line change
@@ -0,0 +1,31 @@
/*
* Copyright (C) 2010 IBM Corporation
* Author: David Safford <safford@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.
*/

#ifndef _KEYS_TRUSTED_TYPE_H
#define _KEYS_TRUSTED_TYPE_H

#include <linux/key.h>
#include <linux/rcupdate.h>

#define MIN_KEY_SIZE 32
#define MAX_KEY_SIZE 128
#define MAX_BLOB_SIZE 320

struct trusted_key_payload {
struct rcu_head rcu;
unsigned int key_len;
unsigned int blob_len;
unsigned char migratable;
unsigned char key[MAX_KEY_SIZE + 1];
unsigned char blob[MAX_BLOB_SIZE];
};

extern struct key_type key_type_trusted;

#endif /* _KEYS_TRUSTED_TYPE_H */
7 changes: 5 additions & 2 deletions include/linux/capability.h
Original file line number Diff line number Diff line change
Expand Up @@ -246,7 +246,6 @@ struct cpu_vfs_cap_data {
/* Allow configuration of the secure attention key */
/* Allow administration of the random device */
/* Allow examination and configuration of disk quotas */
/* Allow configuring the kernel's syslog (printk behaviour) */
/* Allow setting the domainname */
/* Allow setting the hostname */
/* Allow calling bdflush() */
Expand Down Expand Up @@ -352,7 +351,11 @@ struct cpu_vfs_cap_data {

#define CAP_MAC_ADMIN 33

#define CAP_LAST_CAP CAP_MAC_ADMIN
/* Allow configuring the kernel's syslog (printk behaviour) */

#define CAP_SYSLOG 34

#define CAP_LAST_CAP CAP_SYSLOG

#define cap_valid(x) ((x) >= 0 && (x) <= CAP_LAST_CAP)

Expand Down
2 changes: 1 addition & 1 deletion include/linux/flex_array.h
Original file line number Diff line number Diff line change
Expand Up @@ -71,7 +71,7 @@ void *flex_array_get(struct flex_array *fa, unsigned int element_nr);
int flex_array_shrink(struct flex_array *fa);

#define flex_array_put_ptr(fa, nr, src, gfp) \
flex_array_put(fa, nr, &(void *)(src), gfp)
flex_array_put(fa, nr, (void *)&(src), gfp)

void *flex_array_get_ptr(struct flex_array *fa, unsigned int element_nr);

Expand Down
3 changes: 3 additions & 0 deletions include/linux/kernel.h
Original file line number Diff line number Diff line change
Expand Up @@ -56,6 +56,8 @@

#define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f))
#define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))

/* The `const' in roundup() prevents gcc-3.3 from calling __divdi3 */
#define roundup(x, y) ( \
{ \
const typeof(y) __y = y; \
Expand Down Expand Up @@ -263,6 +265,7 @@ static inline char *pack_hex_byte(char *buf, u8 byte)
}

extern int hex_to_bin(char ch);
extern void hex2bin(u8 *dst, const char *src, size_t count);

/*
* General tracing related utility functions - trace_printk(),
Expand Down
3 changes: 1 addition & 2 deletions include/linux/security.h
Original file line number Diff line number Diff line change
Expand Up @@ -1058,8 +1058,7 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts)
* @cred points to the credentials to provide the context against which to
* evaluate the security data on the key.
* @perm describes the combination of permissions required of this key.
* Return 1 if permission granted, 0 if permission denied and -ve it the
* normal permissions model should be effected.
* Return 0 if permission is granted, -ve error otherwise.
* @key_getsecurity:
* Get a textual representation of the security context attached to a key
* for the purposes of honouring KEYCTL_GETSECURITY. This function
Expand Down
4 changes: 4 additions & 0 deletions include/linux/tpm.h
Original file line number Diff line number Diff line change
Expand Up @@ -31,12 +31,16 @@

extern int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf);
extern int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash);
extern int tpm_send(u32 chip_num, void *cmd, size_t buflen);
#else
static inline int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf) {
return -ENODEV;
}
static inline int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash) {
return -ENODEV;
}
static inline int tpm_send(u32 chip_num, void *cmd, size_t buflen) {
return -ENODEV;
}
#endif
#endif
28 changes: 28 additions & 0 deletions include/linux/tpm_command.h
Original file line number Diff line number Diff line change
@@ -0,0 +1,28 @@
#ifndef __LINUX_TPM_COMMAND_H__
#define __LINUX_TPM_COMMAND_H__

/*
* TPM Command constants from specifications at
* http://www.trustedcomputinggroup.org
*/

/* Command TAGS */
#define TPM_TAG_RQU_COMMAND 193
#define TPM_TAG_RQU_AUTH1_COMMAND 194
#define TPM_TAG_RQU_AUTH2_COMMAND 195
#define TPM_TAG_RSP_COMMAND 196
#define TPM_TAG_RSP_AUTH1_COMMAND 197
#define TPM_TAG_RSP_AUTH2_COMMAND 198

/* Command Ordinals */
#define TPM_ORD_GETRANDOM 70
#define TPM_ORD_OSAP 11
#define TPM_ORD_OIAP 10
#define TPM_ORD_SEAL 23
#define TPM_ORD_UNSEAL 24

/* Other constants */
#define SRKHANDLE 0x40000000
#define TPM_NONCE_SIZE 20

#endif
4 changes: 4 additions & 0 deletions include/linux/xattr.h
Original file line number Diff line number Diff line change
Expand Up @@ -40,9 +40,13 @@
#define XATTR_SMACK_SUFFIX "SMACK64"
#define XATTR_SMACK_IPIN "SMACK64IPIN"
#define XATTR_SMACK_IPOUT "SMACK64IPOUT"
#define XATTR_SMACK_EXEC "SMACK64EXEC"
#define XATTR_SMACK_TRANSMUTE "SMACK64TRANSMUTE"
#define XATTR_NAME_SMACK XATTR_SECURITY_PREFIX XATTR_SMACK_SUFFIX
#define XATTR_NAME_SMACKIPIN XATTR_SECURITY_PREFIX XATTR_SMACK_IPIN
#define XATTR_NAME_SMACKIPOUT XATTR_SECURITY_PREFIX XATTR_SMACK_IPOUT
#define XATTR_NAME_SMACKEXEC XATTR_SECURITY_PREFIX XATTR_SMACK_EXEC
#define XATTR_NAME_SMACKTRANSMUTE XATTR_SECURITY_PREFIX XATTR_SMACK_TRANSMUTE

#define XATTR_CAPS_SUFFIX "capability"
#define XATTR_NAME_CAPS XATTR_SECURITY_PREFIX XATTR_CAPS_SUFFIX
Expand Down
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