crypto: Add aesenc_SB_SR_AK

Start adding infrastructure for accelerating guest AES.
Begin with a SubBytes + ShiftRows + AddRoundKey primitive.

Acked-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

1 files changed, 46 insertions, 0 deletions

diff --git a/crypto/aes.c b/crypto/aes.c
index e65c97e..408d92b 100644
--- a/crypto/aes.c
+++ b/crypto/aes.c
@@ -29,6 +29,7 @@
  */
 #include "qemu/osdep.h"
 #include "crypto/aes.h"
+#include "crypto/aes-round.h"
 
 typedef uint32_t u32;
 typedef uint8_t u8;
@@ -1215,6 +1216,51 @@ static const u32 rcon[] = {
         0x1B000000, 0x36000000, /* for 128-bit blocks, Rijndael never uses more than 10 rcon values */
 };
 
+/*
+ * Perform SubBytes + ShiftRows + AddRoundKey.
+ */
+static inline void
+aesenc_SB_SR_AK_swap(AESState *ret, const AESState *st,
+                     const AESState *rk, bool swap)
+{
+    const int swap_b = swap ? 15 : 0;
+    AESState t;
+
+    t.b[swap_b ^ 0x0] = AES_sbox[st->b[swap_b ^ AES_SH(0x0)]];
+    t.b[swap_b ^ 0x1] = AES_sbox[st->b[swap_b ^ AES_SH(0x1)]];
+    t.b[swap_b ^ 0x2] = AES_sbox[st->b[swap_b ^ AES_SH(0x2)]];
+    t.b[swap_b ^ 0x3] = AES_sbox[st->b[swap_b ^ AES_SH(0x3)]];
+    t.b[swap_b ^ 0x4] = AES_sbox[st->b[swap_b ^ AES_SH(0x4)]];
+    t.b[swap_b ^ 0x5] = AES_sbox[st->b[swap_b ^ AES_SH(0x5)]];
+    t.b[swap_b ^ 0x6] = AES_sbox[st->b[swap_b ^ AES_SH(0x6)]];
+    t.b[swap_b ^ 0x7] = AES_sbox[st->b[swap_b ^ AES_SH(0x7)]];
+    t.b[swap_b ^ 0x8] = AES_sbox[st->b[swap_b ^ AES_SH(0x8)]];
+    t.b[swap_b ^ 0x9] = AES_sbox[st->b[swap_b ^ AES_SH(0x9)]];
+    t.b[swap_b ^ 0xa] = AES_sbox[st->b[swap_b ^ AES_SH(0xA)]];
+    t.b[swap_b ^ 0xb] = AES_sbox[st->b[swap_b ^ AES_SH(0xB)]];
+    t.b[swap_b ^ 0xc] = AES_sbox[st->b[swap_b ^ AES_SH(0xC)]];
+    t.b[swap_b ^ 0xd] = AES_sbox[st->b[swap_b ^ AES_SH(0xD)]];
+    t.b[swap_b ^ 0xe] = AES_sbox[st->b[swap_b ^ AES_SH(0xE)]];
+    t.b[swap_b ^ 0xf] = AES_sbox[st->b[swap_b ^ AES_SH(0xF)]];
+
+    /*
+     * Perform the AddRoundKey with generic vectors.
+     * This may be expanded to either host integer or host vector code.
+     * The key and output endianness match, so no bswap required.
+     */
+    ret->v = t.v ^ rk->v;
+}
+
+void aesenc_SB_SR_AK_gen(AESState *r, const AESState *s, const AESState *k)
+{
+    aesenc_SB_SR_AK_swap(r, s, k, false);
+}
+
+void aesenc_SB_SR_AK_genrev(AESState *r, const AESState *s, const AESState *k)
+{
+    aesenc_SB_SR_AK_swap(r, s, k, true);
+}
+
 /**
  * Expand the cipher key into the encryption key schedule.
  */