linux.git/crypto/cts.c, branch v4.4.284

crypto: cts - fix crash on short inputs

2019-01-16T21:16:12+00:00

[It's a minimal fix for a bug that was fixed incidentally by a large
refactoring in v4.8.]

In the CTS template, when the input length is <= one block cipher block
(e.g. <= 16 bytes for AES) pass the correct length to the underlying CBC
transform rather than one block.  This matches the upstream behavior and
makes the encryption/decryption operation correctly return -EINVAL when
1 <= nbytes < bsize or succeed when nbytes == 0, rather than crashing.

This was fixed upstream incidentally by a large refactoring,
commit 0605c41cc53c ("crypto: cts - Convert to skcipher").  But
syzkaller easily trips over this when running on older kernels, as it's
easily reachable via AF_ALG.  Therefore, this patch makes the minimal
fix for older kernels.

Cc: linux-crypto@vger.kernel.org
Fixes: 76cb9521795a ("[CRYPTO] cts: Add CTS mode required for Kerberos AES support")
Signed-off-by: Eric Biggers 
Signed-off-by: Greg Kroah-Hartman

crypto: cts - Weed out non-CBC algorithms

2015-01-20T03:44:15+00:00

The cts algorithm as currently implemented assumes the underlying
is a CBC-mode algorithm.  So this patch adds a check for that to
eliminate bogus combinations of cts with non-CBC modes.

Signed-off-by: Herbert Xu

crypto: cts - Remove bogus use of seqiv

2015-01-20T03:44:15+00:00

The seqiv generator is completely inappropriate for cts as it's
designed for IPsec algorithms.  Since cts users do not actually
use the IV generator we can just fall back to the default.

Signed-off-by: Herbert Xu 
Acked-by: Maciej ?enczykowski

crypto: include crypto- module prefix in template

2014-11-26T12:06:30+00:00

This adds the module loading prefix "crypto-" to the template lookup
as well.

For example, attempting to load 'vfat(blowfish)' via AF_ALG now correctly
includes the "crypto-" prefix at every level, correctly rejecting "vfat":

	net-pf-38
	algif-hash
	crypto-vfat(blowfish)
	crypto-vfat(blowfish)-all
	crypto-vfat

Reported-by: Mathias Krause 
Signed-off-by: Kees Cook 
Acked-by: Mathias Krause 
Signed-off-by: Herbert Xu

crypto: memzero_explicit - make sure to clear out sensitive data

2014-10-17T15:44:07+00:00

Recently, in commit 13aa93c70e71 ("random: add and use memzero_explicit()
for clearing data"), we have found that GCC may optimize some memset()
cases away when it detects a stack variable is not being used anymore
and going out of scope. This can happen, for example, in cases when we
are clearing out sensitive information such as keying material or any
e.g. intermediate results from crypto computations, etc.

With the help of Coccinelle, we can figure out and fix such occurences
in the crypto subsytem as well. Julia Lawall provided the following
Coccinelle program:

  @@
  type T;
  identifier x;
  @@

  T x;
  ... when exists
      when any
  -memset
  +memzero_explicit
     (&x,
  -0,
     ...)
  ... when != x
      when strict

  @@
  type T;
  identifier x;
  @@

  T x[...];
  ... when exists
      when any
  -memset
  +memzero_explicit
     (x,
  -0,
     ...)
  ... when != x
      when strict

Therefore, make use of the drop-in replacement memzero_explicit() for
exactly such cases instead of using memset().

Signed-off-by: Daniel Borkmann 
Cc: Julia Lawall 
Cc: Herbert Xu 
Cc: Theodore Ts'o 
Cc: Hannes Frederic Sowa 
Acked-by: Hannes Frederic Sowa 
Acked-by: Herbert Xu 
Signed-off-by: Theodore Ts'o

crypto: use ERR_CAST

2013-02-04T13:16:53+00:00

Replace PTR_ERR followed by ERR_PTR by ERR_CAST, to be more concise.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// 
@@
expression err,x;
@@
-       err = PTR_ERR(x);
        if (IS_ERR(x))
-                return ERR_PTR(err);
+                return ERR_CAST(x);
// 

Signed-off-by: Julia Lawall 
Signed-off-by: Herbert Xu

[CRYPTO] cts: Init SG tables

2008-06-02T05:46:51+00:00

Steps to reproduce:

	modprobe tcrypt		# with CONFIG_DEBUG_SG=y

testing cts(cbc(aes)) encryption
test 1 (128 bit key):
------------[ cut here ]------------
kernel BUG at include/linux/scatterlist.h:65!
invalid opcode: 0000 [1] PREEMPT SMP DEBUG_PAGEALLOC
CPU 0 
Modules linked in: tea xts twofish twofish_common tcrypt(+) [maaaany]
Pid: 16151, comm: modprobe Not tainted 2.6.26-rc4-fat #7
RIP: 0010:[]  [] :cts:cts_cbc_encrypt+0x151/0x355
RSP: 0018:ffff81016f497a88  EFLAGS: 00010286
RAX: ffffe20009535d58 RBX: ffff81016f497af0 RCX: 0000000087654321
RDX: ffff8100010d4f28 RSI: ffff81016f497ee8 RDI: ffff81016f497ac0
RBP: ffff81016f497c38 R08: 0000000000000000 R09: 0000000000000011
R10: ffffffff00000008 R11: ffff8100010d4f28 R12: ffff81016f497ac0
R13: ffff81016f497b30 R14: 0000000000000010 R15: 0000000000000010
FS:  00007fac6fa276f0(0000) GS:ffffffff8060e000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 00007f12ca7cc000 CR3: 000000016f441000 CR4: 00000000000026e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff4ff0 DR7: 0000000000000400
Process modprobe (pid: 16151, threadinfo ffff81016f496000, task ffff8101755b4ae0)
Stack:  0000000000000001 ffff81016f496000 ffffffff80719f78 0000000000000001
 0000000000000001 ffffffff8020c87c ffff81016f99c918 20646c756f772049
 65687420656b696c 0000000000000020 0000000000000000 0000000033341102
Call Trace:
 [] ? restore_args+0x0/0x30
 [] ? :aes_generic:crypto_aes_expand_key+0x311/0x369
 [] ? check_object+0x15a/0x213
 [] ? init_object+0x6e/0x76
 [] ? __slab_free+0xfc/0x371
 [] :cts:crypto_cts_encrypt+0xbb/0xca
 [] ? :crypto_blkcipher:setkey+0xc7/0xec
 [] :crypto_blkcipher:async_encrypt+0x38/0x3a
 [] :tcrypt:test_cipher+0x261/0x7c6
 [] :tcrypt:tcrypt_mod_init+0x9df/0x1b30
 [] sys_init_module+0x9e/0x1b2
 [] system_call_after_swapgs+0x8a/0x8f
Code: 45 c0 e8 aa 24 63 df 48 c1 e8 0c 48 b9 00 00 00 00 00 e2 ff ff 48 8b 55 88 48 6b c0 68 48 01 c8 b9 21 43 65 87 48 39 4d 80 74 04 <0f> 0b eb fe f6 c2 01 74 04 0f 0b eb fe 83 e2 03 4c 89 ef 44 89 
RIP  [] :cts:cts_cbc_encrypt+0x151/0x355
 RSP 
---[ end trace e8bahiarjand37fd ]---

Signed-off-by: Alexey Dobriyan 
Signed-off-by: Herbert Xu

[CRYPTO] cts: Add CTS mode required for Kerberos AES support

2008-04-21T02:19:23+00:00

Implement CTS wrapper for CBC mode required for support of AES
encryption support for Kerberos (rfc3962).

Signed-off-by: Kevin Coffman 
Signed-off-by: Herbert Xu