X-Git-Url: https://codewiz.org/gitweb?a=blobdiff_plain;f=bertos%2Fsec%2Fprng%2Fx917.c;h=4111aa228d5f5942b5e50fb47472a08d7d3da40b;hb=4d8a6a97c6c0e15296b51d5f02674079bede1aa0;hp=63888c8f3b7ae99bb7f941fc294bc265c3b9b8e2;hpb=f2108fe515132a85c7e84e588789f482f8feb750;p=bertos.git

diff --git a/bertos/sec/prng/x917.c b/bertos/sec/prng/x917.c
index 63888c8f..4111aa22 100644
--- a/bertos/sec/prng/x917.c
+++ b/bertos/sec/prng/x917.c
@@ -33,6 +33,7 @@
  * \brief ANSI X9.17 PRNG implementation
  * \author Giovanni Bajo <rasky@develer.com>
  *
+ * notest:avr
  */
 
 #include "x917.h"
@@ -44,30 +45,28 @@ static void x917_next(X917Context *ctx, BlockCipher *cipher, uint8_t *out)
 {
 	const size_t blen = cipher_block_len(cipher);
 
-	union
+	struct
 	{
-		uint8_t bytes[blen];
-		struct
-		{
-			time_t t0;
-			hptime_t t1;
-		} data;
+		time_t t0;
+		hptime_t t1;
+		uint8_t padding[blen - sizeof(time_t) - sizeof(hptime_t)];
 	} DT;
 
-	ASSERT(sizeof(DT.bytes) >= sizeof(ticks_t) + sizeof(hptime_t));
+	ASSERT(sizeof(DT) == blen);
 
-	DT.data.t0 = timer_clock();
-	DT.data.t1 = timer_hw_hpread();
+	memset(&DT, 0, sizeof(DT));
+	DT.t0 = timer_clock();
+	DT.t1 = timer_hw_hpread();
 
-	cipher_ecb_encrypt(cipher, DT.bytes);
+	cipher_ecb_encrypt(cipher, &DT);
 
-	xor_block(out, DT.bytes, ctx->state, blen);
+	xor_block(out, (uint8_t*)&DT, ctx->state, blen);
 	cipher_ecb_encrypt(cipher, out);
 
-	xor_block(ctx->state, DT.bytes, out, blen);
+	xor_block(ctx->state, (uint8_t*)&DT, out, blen);
 	cipher_ecb_encrypt(cipher, ctx->state);
 
-	PURGE(DT.bytes);
+	PURGE(DT);
 }
 
 
@@ -103,17 +102,24 @@ static void x917_reseed(PRNG *ctx_, const uint8_t *seed)
 	//     of the seed, and use the result as new seed.
 	//   * Generate and throw away a block to update the state.
 	X917Context *ctx = (X917Context *)ctx_;
+	const size_t klen = sizeof(ctx->key);
+	const size_t blen = sizeof(ctx->state);
 
-	size_t klen = sizeof(ctx->key);
-	size_t blen = sizeof(ctx->state);
-
-	uint8_t buf[klen];
-	x917_generate(ctx_, buf, klen);
+	if (!ctx->rng.seeded)
+	{
+		memcpy(ctx->key, seed, klen);
+		memcpy(ctx->state, seed+klen, blen);
+	}
+	else
+	{
+		uint8_t buf[klen];
+		x917_generate(ctx_, buf, klen);
 
-	xor_block(ctx->key, buf, seed, klen);
-	xor_block(ctx->state, ctx->state, seed+klen, blen);
+		xor_block(ctx->key, buf, seed, klen);
+		xor_block(ctx->state, ctx->state, seed+klen, blen);
 
-	PURGE(buf);
+		PURGE(buf);
+	}
 }
 
 /*********************************************************************/