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-rw-r--r--crypto/aes.c59
1 files changed, 59 insertions, 0 deletions
diff --git a/crypto/aes.c b/crypto/aes.c
index ec300cda0c..6c05d731f4 100644
--- a/crypto/aes.c
+++ b/crypto/aes.c
@@ -1323,6 +1323,65 @@ void aesenc_SB_SR_AK_genrev(AESState *r, const AESState *s, const AESState *k)
}
/*
+ * 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.
*/
static inline void