kernel_optimize_test/crypto
Cesar Eduardo Barros fe8c8a1268 crypto: more robust crypto_memneq
Disabling compiler optimizations can be fragile, since a new
optimization could be added to -O0 or -Os that breaks the assumptions
the code is making.

Instead of disabling compiler optimizations, use a dummy inline assembly
(based on RELOC_HIDE) to block the problematic kinds of optimization,
while still allowing other optimizations to be applied to the code.

The dummy inline assembly is added after every OR, and has the
accumulator variable as its input and output. The compiler is forced to
assume that the dummy inline assembly could both depend on the
accumulator variable and change the accumulator variable, so it is
forced to compute the value correctly before the inline assembly, and
cannot assume anything about its value after the inline assembly.

This change should be enough to make crypto_memneq work correctly (with
data-independent timing) even if it is inlined at its call sites. That
can be done later in a followup patch.

Compile-tested on x86_64.

Signed-off-by: Cesar Eduardo Barros <cesarb@cesarb.eti.br>
Acked-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2013-12-05 21:28:41 +08:00
..
asymmetric_keys Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2013-11-23 16:18:25 -08:00
async_tx Merge commit 'dmaengine-3.13-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/dmaengine 2013-11-16 12:02:36 +05:30
842.c
ablk_helper.c crypto: ablk_helper - Replace memcpy with struct assignment 2013-10-07 14:16:57 +08:00
ablkcipher.c crypto: skcipher - Use eseqiv even on UP machines 2013-10-30 09:51:45 +08:00
aead.c
aes_generic.c crypto: make tables used from assembler __visible 2013-08-14 20:42:03 +10:00
af_alg.c tree-wide: use reinit_completion instead of INIT_COMPLETION 2013-11-15 09:32:21 +09:00
ahash.c
algapi.c crypto: sanitize argument for format string 2013-07-03 16:07:25 -07:00
algboss.c crypto: algboss - Hold ref count on larval 2013-06-25 19:15:17 +08:00
algif_hash.c net: rework recvmsg handler msg_name and msg_namelen logic 2013-11-20 21:52:30 -05:00
algif_skcipher.c net: rework recvmsg handler msg_name and msg_namelen logic 2013-11-20 21:52:30 -05:00
ansi_cprng.c crypto: ansi_cprng - Fix off by one error in non-block size request 2013-09-24 06:02:23 +10:00
anubis.c
api.c crypto: api - Fix race condition in larval lookup 2013-09-08 14:33:50 +10:00
arc4.c
authenc.c crypto: authenc - Find proper IV address in ablkcipher callback 2013-11-28 22:16:23 +08:00
authencesn.c crypto: authencesn - Simplify key parsing 2013-10-16 20:56:25 +08:00
blkcipher.c
blowfish_common.c
blowfish_generic.c
camellia_generic.c crypto: camellia_generic - replace commas by semicolons and adjust code alignment 2013-08-21 21:08:33 +10:00
cast_common.c crypto: make tables used from assembler __visible 2013-08-14 20:42:03 +10:00
cast5_generic.c
cast6_generic.c
cbc.c
ccm.c crypto: ccm - Fix handling of zero plaintext when computing mac 2013-11-28 22:25:17 +08:00
chainiv.c
cipher.c
cmac.c crypto: add CMAC support to CryptoAPI 2013-04-25 21:01:47 +08:00
compress.c
crc32.c
crc32c.c
crct10dif_common.c crypto: crct10dif - Add fallback for broken initrds 2013-09-12 15:31:34 +10:00
crct10dif_generic.c crypto: crct10dif - Add fallback for broken initrds 2013-09-12 15:31:34 +10:00
cryptd.c
crypto_null.c
crypto_user.c crypto: user - constify netlink dispatch table 2013-03-10 16:46:43 +08:00
crypto_wq.c
ctr.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2013-02-25 15:56:15 -08:00
cts.c
deflate.c
des_generic.c
ecb.c
eseqiv.c
fcrypt.c crypto: fcrypt - Fix bitoperation for compilation with clang 2013-09-02 20:32:58 +10:00
fips.c
gcm.c crypto: crypto_memneq - add equality testing of memory regions w/o timing leaks 2013-10-07 14:17:06 +08:00
gf128mul.c
ghash-generic.c
hash_info.c crypto: provide single place for hash algo information 2013-10-25 17:14:03 -04:00
hmac.c
internal.h crypto: algboss - Hold ref count on larval 2013-06-25 19:15:17 +08:00
Kconfig Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2013-11-23 16:18:25 -08:00
khazad.c
krng.c
lrw.c
lz4.c crypto: add lz4 Cryptographic API 2013-07-09 10:33:30 -07:00
lz4hc.c crypto: add lz4 Cryptographic API 2013-07-09 10:33:30 -07:00
lzo.c
Makefile crypto: more robust crypto_memneq 2013-12-05 21:28:41 +08:00
md4.c
md5.c
memneq.c crypto: more robust crypto_memneq 2013-12-05 21:28:41 +08:00
michael_mic.c
pcbc.c
pcompress.c
pcrypt.c drivers: avoid format strings in names passed to alloc_workqueue() 2013-07-03 16:07:41 -07:00
proc.c
ripemd.h
rmd128.c
rmd160.c
rmd256.c
rmd320.c
rng.c
salsa20_generic.c
scatterwalk.c crypto: scatterwalk - Add support for calculating number of SG elements 2013-08-21 21:27:58 +10:00
seed.c
seqiv.c
serpent_generic.c
sha1_generic.c
sha256_generic.c crypto: sha256 - Expose SHA256 generic routine to be callable externally. 2013-04-03 09:06:31 +08:00
sha512_generic.c crypto: sha512_generic - set cra_driver_name 2013-05-28 15:43:04 +08:00
shash.c
tcrypt.c crypto: caam - fix aead sglen for case 'dst != src' 2013-11-28 22:25:17 +08:00
tcrypt.h
tea.c
testmgr.c crypto: testmgr - fix sglen in test_aead for case 'dst != src' 2013-11-28 22:25:17 +08:00
testmgr.h Reinstate "crypto: crct10dif - Wrap crc_t10dif function all to use crypto transform framework" 2013-09-07 12:56:26 +10:00
tgr192.c
twofish_common.c
twofish_generic.c
vmac.c
wp512.c
xcbc.c
xor.c
xts.c
zlib.c