Add a primitive for InvMixColumns.
Acked-by: Daniel P. Berrangé <berra...@redhat.com>
Signed-off-by: Richard Henderson <richard.hender...@linaro.org>
---
host/include/generic/host/crypto/aes-round.h | 2 +
include/crypto/aes-round.h | 18 ++++++
crypto/aes.c | 59 ++++++++++++++++++++
3 files changed, 79 insertions(+)
diff --git a/host/include/generic/host/crypto/aes-round.h
b/host/include/generic/host/crypto/aes-round.h
index 1b82afc629..335ec3f11e 100644
--- a/host/include/generic/host/crypto/aes-round.h
+++ b/host/include/generic/host/crypto/aes-round.h
@@ -15,6 +15,8 @@ void aesenc_SB_SR_AK_accel(AESState *, const AESState *,
const AESState *, bool)
QEMU_ERROR("unsupported accel");
+void aesdec_IMC_accel(AESState *, const AESState *, bool)
+ QEMU_ERROR("unsupported accel");
void aesdec_ISB_ISR_AK_accel(AESState *, const AESState *,
const AESState *, bool)
QEMU_ERROR("unsupported accel");
diff --git a/include/crypto/aes-round.h b/include/crypto/aes-round.h
index 7d2be40a67..7be2cc0d8e 100644
--- a/include/crypto/aes-round.h
+++ b/include/crypto/aes-round.h
@@ -59,6 +59,24 @@ static inline void aesenc_SB_SR_AK(AESState *r, const
AESState *st,
}
}
+/*
+ * Perform InvMixColumns.
+ */
+
+void aesdec_IMC_gen(AESState *ret, const AESState *st);
+void aesdec_IMC_genrev(AESState *ret, const AESState *st);
+
+static inline void aesdec_IMC(AESState *r, const AESState *st, bool be)
+{
+ if (HAVE_AES_ACCEL) {
+ aesdec_IMC_accel(r, st, be);
+ } else if (HOST_BIG_ENDIAN == be) {
+ aesdec_IMC_gen(r, st);
+ } else {
+ aesdec_IMC_genrev(r, st);
+ }
+}
+
/*
* Perform InvSubBytes + InvShiftRows + AddRoundKey.
*/
diff --git a/crypto/aes.c b/crypto/aes.c
index ec300cda0c..6c05d731f4 100644
--- a/crypto/aes.c
+++ b/crypto/aes.c
@@ -1322,6 +1322,65 @@ void aesenc_SB_SR_AK_genrev(AESState *r, const AESState
*s, const AESState *k)
aesenc_SB_SR_AK_swap(r, s, k, true);
}
+/*
+ * Perform InvMixColumns.
+ */
+static inline void
+aesdec_IMC_swap(AESState *r, const AESState *st, bool swap)
+{
+ int swap_b = swap * 0xf;
+ int swap_w = swap * 0x3;
+ bool be = HOST_BIG_ENDIAN ^ swap;
+ uint32_t t;
+
+ /* Note that AES_imc is encoded for big-endian. */
+ t = (AES_imc[st->b[swap_b ^ 0x0]][0] ^
+ AES_imc[st->b[swap_b ^ 0x1]][1] ^
+ AES_imc[st->b[swap_b ^ 0x2]][2] ^
+ AES_imc[st->b[swap_b ^ 0x3]][3]);
+ if (!be) {
+ t = bswap32(t);
+ }
+ r->w[swap_w ^ 0] = t;
+
+ t = (AES_imc[st->b[swap_b ^ 0x4]][0] ^
+ AES_imc[st->b[swap_b ^ 0x5]][1] ^
+ AES_imc[st->b[swap_b ^ 0x6]][2] ^
+ AES_imc[st->b[swap_b ^ 0x7]][3]);
+ if (!be) {
+ t = bswap32(t);
+ }
+ r->w[swap_w ^ 1] = t;
+
+ t = (AES_imc[st->b[swap_b ^ 0x8]][0] ^
+ AES_imc[st->b[swap_b ^ 0x9]][1] ^
+ AES_imc[st->b[swap_b ^ 0xA]][2] ^
+ AES_imc[st->b[swap_b ^ 0xB]][3]);
+ if (!be) {
+ t = bswap32(t);
+ }
+ r->w[swap_w ^ 2] = t;
+
+ t = (AES_imc[st->b[swap_b ^ 0xC]][0] ^
+ AES_imc[st->b[swap_b ^ 0xD]][1] ^
+ AES_imc[st->b[swap_b ^ 0xE]][2] ^
+ AES_imc[st->b[swap_b ^ 0xF]][3]);
+ if (!be) {
+ t = bswap32(t);
+ }
+ r->w[swap_w ^ 3] = t;
+}
+
+void aesdec_IMC_gen(AESState *r, const AESState *st)
+{
+ aesdec_IMC_swap(r, st, false);
+}
+
+void aesdec_IMC_genrev(AESState *r, const AESState *st)
+{
+ aesdec_IMC_swap(r, st, true);
+}
+
/*
* Perform InvSubBytes + InvShiftRows + AddRoundKey.
*/
--
2.34.1
