On 1 October 2018 at 09:50, Ondrej Mosnacek <omosnace@xxxxxxxxxx> wrote: > Hi Ard, > > On Sun, Sep 30, 2018 at 10:59 AM Ard Biesheuvel > <ard.biesheuvel@xxxxxxxxxx> wrote: >> Use the correct __le32 annotation and accessors to perform the >> single round of AES encryption performed inside the AEGIS transform. >> Otherwise, tcrypt reports: >> >> alg: aead: Test 1 failed on encryption for aegis128-generic >> 00000000: 6c 25 25 4a 3c 10 1d 27 2b c1 d4 84 9a ef 7f 6e >> alg: aead: Test 1 failed on encryption for aegis128l-generic >> 00000000: cd c6 e3 b8 a0 70 9d 8e c2 4f 6f fe 71 42 df 28 >> alg: aead: Test 1 failed on encryption for aegis256-generic >> 00000000: aa ed 07 b1 96 1d e9 e6 f2 ed b5 8e 1c 5f dc 1c > > Hm... I think the reason I made a mistake here is that I first had a > version with the AES table hard-coded and I had an #ifdef <is big > endian> #else #endif there with values for little-endian and > big-endian variants. Then I realized the aes_generic module exports > the crypto_ft_table and rewrote the code to use that. Somewhere along > the way I forgot to check if the aes_generic table uses the same trick > and correct the code... > > It would be nice to apply the same optimization to aes_generic.c, but > unfortunately the current tables are exported so changing the > convention would break external modules that use them :/ > Indeed. I am doing some refactoring work on the AES code, which is how I ran into this in the first place. https://git.kernel.org/pub/scm/linux/kernel/git/ardb/linux.git/log/?h=for-kernelci >> >> While at it, let's refer to the first precomputed table only, and >> derive the other ones by rotation. This reduces the D-cache footprint >> by 75%, and shouldn't be too costly or free on load/store architectures >> (and X86 has its own AES-NI based implementation) > > Could you maybe extract this into a separate patch? I don't think we > should mix functional and performance fixes together. > Yeah, good point. I will do that and fold in the simplification. >> >> Fixes: f606a88e5823 ("crypto: aegis - Add generic AEGIS AEAD implementations") >> Cc: <stable@xxxxxxxxxxxxxxx> # v4.18+ >> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx> >> --- >> crypto/aegis.h | 23 +++++++++----------- >> 1 file changed, 10 insertions(+), 13 deletions(-) >> >> diff --git a/crypto/aegis.h b/crypto/aegis.h >> index f1c6900ddb80..84d3e07a3c33 100644 >> --- a/crypto/aegis.h >> +++ b/crypto/aegis.h >> @@ -21,7 +21,7 @@ >> >> union aegis_block { >> __le64 words64[AEGIS_BLOCK_SIZE / sizeof(__le64)]; >> - u32 words32[AEGIS_BLOCK_SIZE / sizeof(u32)]; >> + __le32 words32[AEGIS_BLOCK_SIZE / sizeof(__le32)]; >> u8 bytes[AEGIS_BLOCK_SIZE]; >> }; >> >> @@ -59,22 +59,19 @@ static void crypto_aegis_aesenc(union aegis_block *dst, >> { >> u32 *d = dst->words32; >> const u8 *s = src->bytes; >> - const u32 *k = key->words32; >> + const __le32 *k = key->words32; >> const u32 *t0 = crypto_ft_tab[0]; >> - const u32 *t1 = crypto_ft_tab[1]; >> - const u32 *t2 = crypto_ft_tab[2]; >> - const u32 *t3 = crypto_ft_tab[3]; >> u32 d0, d1, d2, d3; >> >> - d0 = t0[s[ 0]] ^ t1[s[ 5]] ^ t2[s[10]] ^ t3[s[15]] ^ k[0]; >> - d1 = t0[s[ 4]] ^ t1[s[ 9]] ^ t2[s[14]] ^ t3[s[ 3]] ^ k[1]; >> - d2 = t0[s[ 8]] ^ t1[s[13]] ^ t2[s[ 2]] ^ t3[s[ 7]] ^ k[2]; >> - d3 = t0[s[12]] ^ t1[s[ 1]] ^ t2[s[ 6]] ^ t3[s[11]] ^ k[3]; >> + d0 = t0[s[ 0]] ^ rol32(t0[s[ 5]], 8) ^ rol32(t0[s[10]], 16) ^ rol32(t0[s[15]], 24); >> + d1 = t0[s[ 4]] ^ rol32(t0[s[ 9]], 8) ^ rol32(t0[s[14]], 16) ^ rol32(t0[s[ 3]], 24); >> + d2 = t0[s[ 8]] ^ rol32(t0[s[13]], 8) ^ rol32(t0[s[ 2]], 16) ^ rol32(t0[s[ 7]], 24); >> + d3 = t0[s[12]] ^ rol32(t0[s[ 1]], 8) ^ rol32(t0[s[ 6]], 16) ^ rol32(t0[s[11]], 24); >> >> - d[0] = d0; >> - d[1] = d1; >> - d[2] = d2; >> - d[3] = d3; >> + d[0] = cpu_to_le32(d0 ^ le32_to_cpu(k[0])); >> + d[1] = cpu_to_le32(d1 ^ le32_to_cpu(k[1])); >> + d[2] = cpu_to_le32(d2 ^ le32_to_cpu(k[2])); >> + d[3] = cpu_to_le32(d3 ^ le32_to_cpu(k[3])); >> } >> >> #endif /* _CRYPTO_AEGIS_H */ >> -- >> 2.19.0 >> > > Thanks, > > -- > Ondrej Mosnacek <omosnace at redhat dot com> > Associate Software Engineer, Security Technologies > Red Hat, Inc.
