Re: [RFC][PATCH v2 5/6] encrypted-keys: add ecryptfs format support

[Roberto Sassu]

On Wednesday, January 05, 2011 09:17:24 am Tyler Hicks wrote:
> On Tue Dec 28, 2010 at 11:48:15AM +0100, Roberto Sassu <roberto.sassu@xxxxxxxxx> wrote:
> > The 'encrypted' key type defines its own payload format which contains a
> > symmetric key randomly generated that cannot be used directly to mount
> > an eCryptfs filesystem, because it expects an authentication token
> > structure.
> > 
> > This patch introduces the new format 'ecryptfs' that allows to store an
> > authentication token structure inside the encrypted key payload containing
> > a randomly generated symmetric key, as the same for the format 'default'.
> > 
> > More details about the usage of encrypted keys with the eCryptfs
> > filesystem can be found in the file 'Documentation/keys-ecryptfs.txt'.
> > 
> > Signed-off-by: Roberto Sassu <roberto.sassu@xxxxxxxxx>
> > ---
> >  Documentation/keys-ecryptfs.txt          |   68 +++++++++++++++++++++++++
> >  Documentation/keys-trusted-encrypted.txt |    6 ++-
> >  security/keys/Makefile                   |    2 +-
> >  security/keys/encrypted_defined.c        |   75 +++++++++++++++++++++++++---
> >  security/keys/keys_ecryptfs.c            |   81 ++++++++++++++++++++++++++++++
> >  security/keys/keys_ecryptfs.h            |   30 +++++++++++
> >  6 files changed, 252 insertions(+), 10 deletions(-)
> >  create mode 100644 Documentation/keys-ecryptfs.txt
> >  create mode 100644 security/keys/keys_ecryptfs.c
> >  create mode 100644 security/keys/keys_ecryptfs.h
> > 
> > diff --git a/Documentation/keys-ecryptfs.txt b/Documentation/keys-ecryptfs.txt
> > new file mode 100644
> > index 0000000..c3bbeba
> > --- /dev/null
> > +++ b/Documentation/keys-ecryptfs.txt
> > @@ -0,0 +1,68 @@
> > +		Encrypted keys for the eCryptfs filesystem
> > +
> > +ECryptfs is a stacked filesystem which transparently encrypts and decrypts each
> > +file using a randomly generated File Encryption Key (FEK).
> > +
> > +Each FEK is in turn encrypted with a File Encryption Key Encryption Key (FEFEK)
> > +either in kernel space or in user space with a daemon called 'ecryptfsd'.  In
> > +the former case the operation is performed directly by the kernel CryptoAPI
> > +using a key, the FEFEK, derived from a user prompted passphrase;  in the latter
> > +the FEK is encrypted by 'ecryptfsd' with the help of external libraries in order
> > +to support other mechanisms like public key cryptography, PKCS#11 and TPM based
> > +operations.
> > +
> > +The data structure defined by eCryptfs to contain information required for the
> > +FEK decryption is called authentication token and, currently, can be stored in a
> > +kernel key of the 'user' type, inserted in the user's session specific keyring
> > +by the userspace utility 'mount.ecryptfs' shipped with the package
> > +'ecryptfs-utils'.
> > +
> > +The 'encrypted' key type has been extended with the introduction of the new
> > +format 'ecryptfs' in order to be used in conjunction with the eCryptfs
> > +filesystem.  Encrypted keys of the newly introduced format store an
> > +authentication token in its payload with a FEFEK randomly generated by the
> > +kernel and protected by the parent master key.
> > +
> > +In order to avoid known-plaintext attacks, the datablob obtained through
> > +commands 'keyctl print' or 'keyctl pipe' does not contain the overall
> > +authentication token, which content is well known, but only the FEFEK in
> > +encrypted form.
> > +
> > +The eCryptfs filesystem may really benefit from using encrypted keys in that the
> > +required key can be securely generated by an Administrator and provided at boot
> > +time after the unsealing of a 'trusted' key in order to perform the mount in a
> > +controlled environment.  Another advantage is that the key is not exposed to
> > +threats of malicious software, because it is available in clear form only at
> > +kernel level.
> 
> This is a great idea. Thanks for integrating the two.
> 
> > +
> > +Usage:
> > +   keyctl add encrypted name "new ecryptfs key-type:master-key-name keylen" ring
> > +   keyctl add encrypted name "load hex_blob" ring
> 
> I get a lockdep warning on this step. I'm not sure if it an existing
> encrypted key problem or brought about by this patch set.
> 
> I'm using 2.6.37, with the security tree's next branch pulled in, and
> these patches applied.
> 
> For testing purposes, ecryptfs.mkey is a file, containing 64 random
> bytes, used as the master key. The contents are:
> 
> $ hexdump ecryptfs.mkey 
> 0000000 5893 18c9 85de 25ac 101c e184 e754 fd65
> 0000010 2e65 5f88 ba90 158b 8c47 2134 c097 796d
> 0000020 2fe4 0651 6fdf 9898 edad 685e c3d7 b48c
> 0000030 462a 9385 1604 f19d fbda 3177 f849 ede3
> 0000040
> 
> ecryptfs.ekey is a file containing the eCryptfs encrypted key blob. It
> was created by following your directions below. The contents are:
> 
> $ cat ecryptfs.ekey 
> ecryptfs user:master_key 64
> 6dc63e48419754a9388c507c500a2d0f00af19baf81af8350b288b5e884e1f13d93d5bc94a2557a6c285077cde9ba8caf3fa259c6f5c19e238d37753f10c814184aa6f9587d0a49347b01b54359fe4ada7e78a1142e9c924479644fe1ec635d2fd482b3c99c2453ccd1ae46a8cbfbe5d2e
> 
> I run these 2 commands:
> 
> $ keyctl add user master_key `cat ecryptfs.mkey` @u
> 383197512
> $ keyctl add encrypted deadbeefDEADBEEF "load `cat ecryptfs.ekey`" @u
> 483096946
> 
> and I get this lockdep warning after adding the encrypted key:
> 
> =============================================
> [ INFO: possible recursive locking detected ]
> 2.6.37-test+ #16
> ---------------------------------------------
> keyctl/1140 is trying to acquire lock:
>  (&key->sem){+++++.}, at: [<ffffffff8118cff8>] request_master_key+0xb5/0xf6
> 
> but task is already holding lock:
>  (&key->sem){+++++.}, at: [<ffffffff8118792c>] __key_link_begin+0x46/0x229
> 
> other info that might help us debug this:
> 3 locks held by keyctl/1140:
>  #0:  (key_types_sem){++++.+}, at: [<ffffffff811861eb>] key_type_lookup+0x21/0x76
>  #1:  (&key->sem){+++++.}, at: [<ffffffff8118792c>] __key_link_begin+0x46/0x229
>  #2:  (key_construction_mutex){+.+.+.}, at: [<ffffffff81185f09>] __key_instantiate_and_link+0x37/0xf8
> 
> stack backtrace:
> Pid: 1140, comm: keyctl Not tainted 2.6.37-test+ #16
> Call Trace:
>  [<ffffffff810658b0>] __lock_acquire+0xcb4/0xd2f
>  [<ffffffff8118b09c>] ? user_match+0x0/0x1f
>  [<ffffffff811897ea>] ? search_process_keyrings+0x4b/0x108
>  [<ffffffff81065a0e>] lock_acquire+0xe3/0x110
>  [<ffffffff8118cff8>] ? request_master_key+0xb5/0xf6
>  [<ffffffff811ceab2>] ? strict_strtoul+0x2a/0x58
>  [<ffffffff8135ed85>] down_read+0x4c/0x61
>  [<ffffffff8118cff8>] ? request_master_key+0xb5/0xf6
>  [<ffffffff8118d874>] ? encrypted_key_alloc+0x134/0x168
>  [<ffffffff8118cff8>] request_master_key+0xb5/0xf6
>  [<ffffffff8118dd6a>] encrypted_instantiate+0x267/0x375
>  [<ffffffff81185f3e>] __key_instantiate_and_link+0x6c/0xf8
>  [<ffffffff81186b16>] key_create_or_update+0x16a/0x268
>  [<ffffffff8118a064>] ? lookup_user_key+0x32b/0x39f
>  [<ffffffff811890e5>] sys_add_key+0x112/0x18d
>  [<ffffffff81063f43>] ? trace_hardirqs_on_caller+0x11d/0x141
>  [<ffffffff81350064>] ? pci_scan_single_device+0x8d/0x142
>  [<ffffffff81002bc2>] system_call_fastpath+0x16/0x1b
> 
> I haven't looked into it any further.
> 
> Tyler
> 

Hi Tyler and all

i made some tests and i found this message is caused
by lines #228 and #251 of the original source file
'security/keys/encrypted_defined.c':

---
down_read(&tkey->sem);
---

and

---
down_read(&ukey->sem);
---

The warning message tells that there is a possible
deadlock when requesting the master key required for
the 'encrypted' key decryption.
In particular, the deadlock can happen if the requested
key is the user's session-specific keyring, because this is
already write locked in the function __key_link_begin()
of the source file 'security/keys/keyring.c'.

It is possible to verify the deadlock condition by replacing
the line #247 of the source file
'security/keys/encrypted_defined.c':

---
ukey = request_key(&key_type_user, master_desc, NULL);
---

with:

---
ukey = request_key(&key_type_keyring, "_uid.0", NULL);
---

and loading a previously generated encrypted key which
master key is of the 'user' type.

The reported case won't ever happen because allowed
master key types are only 'trusted' and 'user'.

Roberto Sassu


> > +   keyctl update keyid "update key-type:master-key-name"
> > +
> > +name:= '<16 hexadecimal characters>'
> > +key-type:= 'trusted' | 'user'
> > +keylen:= 64
> > +
> > +
> > +Example of encrypted key usage with the eCryptfs filesystem:
> > +
> > +Create an encrypted key "1000100010001000" of length 64 bytes with format
> > +'ecryptfs' and save it using a previously loaded user key "test":
> > +
> > +    $ keyctl add encrypted 1000100010001000 "new ecryptfs user:test 64" @u
> > +    19184530
> > +
> > +    $ keyctl print 19184530
> > +    ecryptfs user:test 64 490045d4bfe48c99f0d465fbbbb79e7500da954178e2de0697
> > +    dd85091f5450a0511219e9f7cd70dcd498038181466f78ac8d4c19504fcc72402bfc41c2
> > +    f253a41b7507ccaa4b2b03fff19a69d1cc0b16e71746473f023a95488b6edfd86f7fdd40
> > +    9d292e4bacded1258880122dd553a661
> > +
> > +    $ keyctl pipe 19184530 > ecryptfs.blob
> > +
> > +Mount an eCryptfs filesystem using the created encrypted key "1000100010001000"
> > +into the '/secret' directory:
> > +
> > +    $ mount -i -t ecryptfs -oecryptfs_sig=1000100010001000,\
> > +      ecryptfs_cipher=aes,ecryptfs_key_bytes=32 /secret /secret
> > diff --git a/Documentation/keys-trusted-encrypted.txt b/Documentation/keys-trusted-encrypted.txt
> > index 0afcb50..5f50cca 100644
> > --- a/Documentation/keys-trusted-encrypted.txt
> > +++ b/Documentation/keys-trusted-encrypted.txt
> > @@ -63,7 +63,7 @@ Usage:
> >      keyctl add encrypted name "load hex_blob" ring
> >      keyctl update keyid "update key-type:master-key-name"
> > 
> > -format:= 'default'
> > +format:= 'default | ecryptfs'
> >  key-type:= 'trusted' | 'user'
> > 
> > 
> > @@ -154,4 +154,6 @@ Load an encrypted key "evm" from saved blob:
> >      24717c64 5972dcb82ab2dde83376d82b2e3c09ffc
> > 
> >  Other uses for trusted and encrypted keys, such as for disk and file encryption
> > -are anticipated.
> > +are anticipated.  In particular the new format 'ecryptfs' has been defined in
> > +in order to use encrypted keys to mount an eCryptfs filesystem.  More details
> > +about the usage can be found in the file 'Documentation/keys-ecryptfs.txt'.
> > diff --git a/security/keys/Makefile b/security/keys/Makefile
> > index 6c94105..c50b422 100644
> > --- a/security/keys/Makefile
> > +++ b/security/keys/Makefile
> > @@ -14,7 +14,7 @@ obj-y := \
> >  	user_defined.o
> > 
> >  obj-$(CONFIG_TRUSTED_KEYS) += trusted_defined.o
> > -obj-$(CONFIG_ENCRYPTED_KEYS) += encrypted_defined.o
> > +obj-$(CONFIG_ENCRYPTED_KEYS) += keys_ecryptfs.o encrypted_defined.o
> >  obj-$(CONFIG_KEYS_COMPAT) += compat.o
> >  obj-$(CONFIG_PROC_FS) += proc.o
> >  obj-$(CONFIG_SYSCTL) += sysctl.o
> > diff --git a/security/keys/encrypted_defined.c b/security/keys/encrypted_defined.c
> > index 7a914ab..2f7f314 100644
> > --- a/security/keys/encrypted_defined.c
> > +++ b/security/keys/encrypted_defined.c
> > @@ -29,11 +29,13 @@
> >  #include <linux/rcupdate.h>
> >  #include <linux/scatterlist.h>
> >  #include <linux/crypto.h>
> > +#include <linux/ctype.h>
> >  #include <crypto/hash.h>
> >  #include <crypto/sha.h>
> >  #include <crypto/aes.h>
> > 
> >  #include "encrypted_defined.h"
> > +#include "keys_ecryptfs.h"
> > 
> >  static const char KEY_TRUSTED_PREFIX[] = "trusted:";
> >  static const char KEY_USER_PREFIX[] = "user:";
> > @@ -41,11 +43,13 @@ static const char hash_alg[] = "sha256";
> >  static const char hmac_alg[] = "hmac(sha256)";
> >  static const char blkcipher_alg[] = "cbc(aes)";
> >  static const char key_format_default[] = "default";
> > +static const char key_format_ecryptfs[] = "ecryptfs";
> >  static unsigned int ivsize;
> >  static int blksize;
> > 
> >  #define KEY_TRUSTED_PREFIX_LEN (sizeof (KEY_TRUSTED_PREFIX) - 1)
> >  #define KEY_USER_PREFIX_LEN (sizeof (KEY_USER_PREFIX) - 1)
> > +#define KEY_ECRYPTFS_DESC_LEN 16
> >  #define HASH_SIZE SHA256_DIGEST_SIZE
> >  #define MAX_DATA_SIZE 4096
> >  #define MIN_DATA_SIZE  20
> > @@ -63,11 +67,12 @@ enum {
> >  };
> > 
> >  enum {
> > -	Opt_error = -1, Opt_default
> > +	Opt_error = -1, Opt_default, Opt_ecryptfs
> >  };
> > 
> >  static const match_table_t key_format_tokens = {
> >  	{Opt_default, "default"},
> > +	{Opt_ecryptfs, "ecryptfs"},
> >  	{Opt_error, NULL}
> >  };
> > 
> > @@ -95,6 +100,34 @@ static int aes_get_sizes(void)
> >  }
> > 
> >  /*
> > + * valid_ecryptfs_desc - verify the description of a new/loaded encrypted key
> > + *
> > + * The description of a encrypted key with format 'ecryptfs' must contain
> > + * exactly 16 hexadecimal characters.
> > + *
> > + */
> > +static int valid_ecryptfs_desc(const char *ecryptfs_desc)
> > +{
> > +	int i;
> > +
> > +	if (strlen(ecryptfs_desc) != KEY_ECRYPTFS_DESC_LEN) {
> > +		pr_err("encrypted_key: key description must be %d hexadecimal "
> > +		       "characters long\n", KEY_ECRYPTFS_DESC_LEN);
> > +		return -EINVAL;
> > +	}
> > +
> > +	for (i = 0; i < KEY_ECRYPTFS_DESC_LEN; i++) {
> > +		if (!isxdigit(ecryptfs_desc[i])) {
> > +			pr_err("encrypted_key: key description must contain "
> > +			       "only hexadecimal characters\n");
> > +			return -EINVAL;
> > +		}
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> > +/*
> >   * valid_master_desc - verify the 'key-type:desc' of a new/updated master-key
> >   *
> >   * key-type:= "trusted:" | "user:"
> > @@ -158,7 +191,7 @@ static int datablob_parse(char *datablob, const char **format,
> >  	}
> >  	key_cmd = match_token(keyword, key_tokens, args);
> > 
> > -	/* Get optional format: default */
> > +	/* Get optional format: default | ecryptfs */
> >  	p = strsep(&datablob, " \t");
> >  	if (!p) {
> >  		pr_err("encrypted_key: insufficient parameters specified\n");
> > @@ -167,6 +200,7 @@ static int datablob_parse(char *datablob, const char **format,
> > 
> >  	key_format = match_token(p, key_format_tokens, args);
> >  	switch (key_format) {
> > +	case Opt_ecryptfs:
> >  	case Opt_default:
> >  		*format = p;
> >  		*master_desc = strsep(&datablob, " \t");
> > @@ -598,6 +632,17 @@ static struct encrypted_key_payload *encrypted_key_alloc(struct key *key,
> >  	format_len = (!format) ? strlen(key_format_default) : strlen(format);
> >  	decrypted_datalen = dlen;
> >  	payload_datalen = decrypted_datalen;
> > +	if (format && !strcmp(format, key_format_ecryptfs)) {
> > +		if (dlen != ECRYPTFS_MAX_KEY_BYTES) {
> > +			pr_err("encrypted_key: keylen for the ecryptfs format "
> > +			       "must be equal to %d bytes\n",
> > +			       ECRYPTFS_MAX_KEY_BYTES);
> > +			return ERR_PTR(-EINVAL);
> > +		}
> > +		decrypted_datalen = ECRYPTFS_MAX_KEY_BYTES;
> > +		payload_datalen = sizeof(struct ecryptfs_auth_tok);
> > +	}
> > +
> >  	encrypted_datalen = roundup(decrypted_datalen, blksize);
> > 
> >  	datablob_len = format_len + 1 + strlen(master_desc) + 1
> > @@ -683,8 +728,14 @@ static void __ekey_init(struct encrypted_key_payload *epayload,
> > 
> >  	if (!format)
> >  		memcpy(epayload->format, key_format_default, format_len);
> > -	else
> > +	else {
> > +		if (!strcmp(format, key_format_ecryptfs))
> > +			epayload->decrypted_data =
> > +				ecryptfs_get_auth_tok_key((struct ecryptfs_auth_tok *)epayload->payload_data);
> > +
> >  		memcpy(epayload->format, format, format_len);
> > +	}
> > +
> >  	memcpy(epayload->master_desc, master_desc, strlen(master_desc));
> >  	memcpy(epayload->datalen, datalen, strlen(datalen));
> >  }
> > @@ -696,11 +747,21 @@ static void __ekey_init(struct encrypted_key_payload *epayload,
> >   * itself.  For an old key, decrypt the hex encoded data.
> >   */
> >  static int encrypted_init(struct encrypted_key_payload *epayload,
> > -			  const char *format, const char *master_desc,
> > -			  const char *datalen, const char *hex_encoded_iv)
> > +			  const char *key_desc, const char *format,
> > +			  const char *master_desc, const char *datalen,
> > +			  const char *hex_encoded_iv)
> >  {
> >  	int ret = 0;
> > 
> > +	if (format && !strcmp(format, key_format_ecryptfs)) {
> > +		ret = valid_ecryptfs_desc(key_desc);
> > +		if (ret < 0)
> > +			return ret;
> > +
> > +		ecryptfs_fill_auth_tok((struct ecryptfs_auth_tok *)epayload->payload_data,
> > +				       key_desc);
> > +	}
> > +
> >  	__ekey_init(epayload, format, master_desc, datalen);
> >  	if (!hex_encoded_iv) {
> >  		get_random_bytes(epayload->iv, ivsize);
> > @@ -750,8 +811,8 @@ static int encrypted_instantiate(struct key *key, const void *data,
> >  		ret = PTR_ERR(epayload);
> >  		goto out;
> >  	}
> > -	ret = encrypted_init(epayload, format, master_desc, decrypted_datalen,
> > -			     hex_encoded_iv);
> > +	ret = encrypted_init(epayload, key->description, format, master_desc,
> > +			     decrypted_datalen, hex_encoded_iv);
> >  	if (ret < 0) {
> >  		kfree(epayload);
> >  		goto out;
> > diff --git a/security/keys/keys_ecryptfs.c b/security/keys/keys_ecryptfs.c
> > new file mode 100644
> > index 0000000..6144b91
> > --- /dev/null
> > +++ b/security/keys/keys_ecryptfs.c
> > @@ -0,0 +1,81 @@
> > +/*
> > + * keys_ecryptfs.c: helper functions for the encrypted key type
> > + *
> > + * Copyright (C) 2006 International Business Machines Corp.
> > + * Copyright (C) 2010 Politecnico di Torino, Italy
> > + *                    TORSEC group -- http://security.polito.it
> > + *
> > + * Authors:
> > + * Michael A. Halcrow <mahalcro@xxxxxxxxxx>
> > + * Tyler Hicks <tyhicks@xxxxxx>
> > + * 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.
> > + */
> > +
> > +#include <linux/module.h>
> > +#include "keys_ecryptfs.h"
> > +
> > +u8 *ecryptfs_get_auth_tok_key(struct ecryptfs_auth_tok *auth_tok)
> > +{
> > +	return auth_tok->token.password.session_key_encryption_key;
> > +}
> > +EXPORT_SYMBOL(ecryptfs_get_auth_tok_key);
> > +
> > +/*
> > + * ecryptfs_get_versions()
> > + *
> > + * Source code taken from the software 'ecryptfs-utils' version 83.
> > + *
> > + */
> > +void ecryptfs_get_versions(int *major, int *minor, int *file_version)
> > +{
> > +	*major = ECRYPTFS_VERSION_MAJOR;
> > +	*minor = ECRYPTFS_VERSION_MINOR;
> > +	if (file_version)
> > +		*file_version = ECRYPTFS_SUPPORTED_FILE_VERSION;
> > +}
> > +EXPORT_SYMBOL(ecryptfs_get_versions);
> > +
> > +/*
> > + * ecryptfs_fill_auth_tok - fill the ecryptfs_auth_tok structure
> > + *
> > + * Fill the ecryptfs_auth_tok structure with required ecryptfs data.
> > + * The source code is inspired to the original function generate_payload()
> > + * shipped with the software 'ecryptfs-utils' version 83.
> > + *
> > + */
> > +int ecryptfs_fill_auth_tok(struct ecryptfs_auth_tok *auth_tok,
> > +			   const char *key_desc)
> > +{
> > +	int major, minor;
> > +
> > +	ecryptfs_get_versions(&major, &minor, NULL);
> > +	auth_tok->version = (((uint16_t)(major << 8) & 0xFF00)
> > +			     | ((uint16_t)minor & 0x00FF));
> > +	auth_tok->token_type = ECRYPTFS_PASSWORD;
> > +	strncpy((char *)auth_tok->token.password.signature, key_desc,
> > +		ECRYPTFS_PASSWORD_SIG_SIZE);
> > +	auth_tok->token.password.session_key_encryption_key_bytes =
> > +		ECRYPTFS_MAX_KEY_BYTES;
> > +	/*
> > +	 * Removed auth_tok->token.password.salt and
> > +	 * auth_tok->token.password.session_key_encryption_key
> > +	 * initialization from the original code
> > +	 */
> > +	/* TODO: Make the hash parameterizable via policy */
> > +	auth_tok->token.password.flags |=
> > +		ECRYPTFS_SESSION_KEY_ENCRYPTION_KEY_SET;
> > +	/* The kernel code will encrypt the session key. */
> > +	auth_tok->session_key.encrypted_key[0] = 0;
> > +	auth_tok->session_key.encrypted_key_size = 0;
> > +	/* Default; subject to change by kernel eCryptfs */
> > +	auth_tok->token.password.hash_algo = PGP_DIGEST_ALGO_SHA512;
> > +	auth_tok->token.password.flags &= ~(ECRYPTFS_PERSISTENT_PASSWORD);
> > +	return 0;
> > +}
> > +EXPORT_SYMBOL(ecryptfs_fill_auth_tok);
> > +
> > +MODULE_LICENSE("GPL");
> > diff --git a/security/keys/keys_ecryptfs.h b/security/keys/keys_ecryptfs.h
> > new file mode 100644
> > index 0000000..87f77ca
> > --- /dev/null
> > +++ b/security/keys/keys_ecryptfs.h
> > @@ -0,0 +1,30 @@
> > +/*
> > + * keys_ecryptfs.h: helper functions for the encrypted key type
> > + *
> > + * Copyright (C) 2006 International Business Machines Corp.
> > + * Copyright (C) 2010 Politecnico di Torino, Italy
> > + *                    TORSEC group -- http://security.polito.it
> > + *
> > + * Authors:
> > + * Michael A. Halcrow <mahalcro@xxxxxxxxxx>
> > + * Tyler Hicks <tyhicks@xxxxxx>
> > + * 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.
> > + */
> > +
> > +#ifndef __KEYS_ECRYPTFS_H
> > +#define __KEYS_ECRYPTFS_H
> > +
> > +#include <linux/ecryptfs.h>
> > +
> > +#define PGP_DIGEST_ALGO_SHA512   10
> > +
> > +u8 *ecryptfs_get_auth_tok_key(struct ecryptfs_auth_tok *auth_tok);
> > +void ecryptfs_get_versions(int *major, int *minor, int *file_version);
> > +int ecryptfs_fill_auth_tok(struct ecryptfs_auth_tok *auth_tok,
> > +			   const char *key_desc);
> > +
> > +#endif /* __KEYS_ECRYPTFS_H */
> 
> 
> 
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/