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-rw-r--r--contrib/bearssl/src/symcipher/aes_small_enc.c129
1 files changed, 129 insertions, 0 deletions
diff --git a/contrib/bearssl/src/symcipher/aes_small_enc.c b/contrib/bearssl/src/symcipher/aes_small_enc.c
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index 000000000000..29f48a8f4f6e
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+++ b/contrib/bearssl/src/symcipher/aes_small_enc.c
@@ -0,0 +1,129 @@
+/*
+ * Copyright (c) 2016 Thomas Pornin <pornin@bolet.org>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include "inner.h"
+
+#define S br_aes_S
+
+static void
+add_round_key(unsigned *state, const uint32_t *skeys)
+{
+ int i;
+
+ for (i = 0; i < 16; i += 4) {
+ uint32_t k;
+
+ k = *skeys ++;
+ state[i + 0] ^= (unsigned)(k >> 24);
+ state[i + 1] ^= (unsigned)(k >> 16) & 0xFF;
+ state[i + 2] ^= (unsigned)(k >> 8) & 0xFF;
+ state[i + 3] ^= (unsigned)k & 0xFF;
+ }
+}
+
+static void
+sub_bytes(unsigned *state)
+{
+ int i;
+
+ for (i = 0; i < 16; i ++) {
+ state[i] = S[state[i]];
+ }
+}
+
+static void
+shift_rows(unsigned *state)
+{
+ unsigned tmp;
+
+ tmp = state[1];
+ state[1] = state[5];
+ state[5] = state[9];
+ state[9] = state[13];
+ state[13] = tmp;
+
+ tmp = state[2];
+ state[2] = state[10];
+ state[10] = tmp;
+ tmp = state[6];
+ state[6] = state[14];
+ state[14] = tmp;
+
+ tmp = state[15];
+ state[15] = state[11];
+ state[11] = state[7];
+ state[7] = state[3];
+ state[3] = tmp;
+}
+
+static void
+mix_columns(unsigned *state)
+{
+ int i;
+
+ for (i = 0; i < 16; i += 4) {
+ unsigned s0, s1, s2, s3;
+ unsigned t0, t1, t2, t3;
+
+ s0 = state[i + 0];
+ s1 = state[i + 1];
+ s2 = state[i + 2];
+ s3 = state[i + 3];
+ t0 = (s0 << 1) ^ s1 ^ (s1 << 1) ^ s2 ^ s3;
+ t1 = s0 ^ (s1 << 1) ^ s2 ^ (s2 << 1) ^ s3;
+ t2 = s0 ^ s1 ^ (s2 << 1) ^ s3 ^ (s3 << 1);
+ t3 = s0 ^ (s0 << 1) ^ s1 ^ s2 ^ (s3 << 1);
+ state[i + 0] = t0 ^ ((unsigned)(-(int)(t0 >> 8)) & 0x11B);
+ state[i + 1] = t1 ^ ((unsigned)(-(int)(t1 >> 8)) & 0x11B);
+ state[i + 2] = t2 ^ ((unsigned)(-(int)(t2 >> 8)) & 0x11B);
+ state[i + 3] = t3 ^ ((unsigned)(-(int)(t3 >> 8)) & 0x11B);
+ }
+}
+
+/* see inner.h */
+void
+br_aes_small_encrypt(unsigned num_rounds, const uint32_t *skey, void *data)
+{
+ unsigned char *buf;
+ unsigned state[16];
+ unsigned u;
+
+ buf = data;
+ for (u = 0; u < 16; u ++) {
+ state[u] = buf[u];
+ }
+ add_round_key(state, skey);
+ for (u = 1; u < num_rounds; u ++) {
+ sub_bytes(state);
+ shift_rows(state);
+ mix_columns(state);
+ add_round_key(state, skey + (u << 2));
+ }
+ sub_bytes(state);
+ shift_rows(state);
+ add_round_key(state, skey + (num_rounds << 2));
+ for (u = 0; u < 16; u ++) {
+ buf[u] = state[u];
+ }
+}