X-Git-Url: https://codewiz.org/gitweb?a=blobdiff_plain;f=bertos%2Fsec%2Futil.h;h=2fcf1b8f0926342ab5cabf30a80832fb83cc7538;hb=7911a6f01bc8a19f220f98e2fdc8595f65996853;hp=36ce22f883a26d5917ce23e573898fe6331a2e2d;hpb=f3a74d05913e05818c39b796968fda9277e213f9;p=bertos.git

diff --git a/bertos/sec/util.h b/bertos/sec/util.h
index 36ce22f8..2fcf1b8f 100644
--- a/bertos/sec/util.h
+++ b/bertos/sec/util.h
@@ -1,13 +1,14 @@
 #ifndef SEC_UTIL_H
 #define SEC_UTIL_H
 
+#include <cfg/macros.h>
 #include <cfg/compiler.h>
 #include <cfg/debug.h>
 #include <string.h>
 
 /**
  * Purge local variables, by zeroing them.
- * 
+ *
  * This can be used to clear stack from intermediate results in crypto
  * calculations that might somehow be leaked.
  */
@@ -17,80 +18,106 @@
 /**
  * Convert a generic "password" (low-diffused) to a generic "key"
  * (high-diffused).
- * 
+ *
  * In common terminology, a "password" is a key with weak cryptographic
- * characteristics, such as commonly used password input by an user, 
+ * characteristics, such as commonly used password input by an user,
  * which are usually short and use only a few different characters from
  * the 0-255 byte range.
- * 
+ *
  * This function derives a strong key from the password using a one-way
  * process.
- * 
+ *
  * \note Uses PBKDF2 as key-derivation function, with a fixed salt that
  * changes for each Bertos project.
  */
 void password2key(const char *pwd, size_t pwd_len,
 				  uint8_t *key, size_t key_len);
-				  
-/**
- * Perform a bitwise xor between \a in and \a inout, and store
- * the result into \a inout.
- */
-INLINE void xor_block(uint8_t *out, const uint8_t *in1, const uint8_t* in2, size_t len);
-
-/**
- * Perform a bitwise xor over \a inout with constant \a k.
- */
-INLINE void xor_block_const(uint8_t *out, const uint8_t *in, uint8_t k, size_t len);
-
 
-// FIXME: provide non-32bit fallback
-// FIXME: proper ifdef conditional
-#if 1 // 32-bit optimized versions
+INLINE void xor_block_8(uint8_t *out,
+		const uint8_t *in1, const uint8_t *in2, size_t len)
+{
+	while (len--)
+                *out++ = *in1++ ^ *in2++;
+}
 
-// FIXME: this code is currently buggy because it ignores alignment issues.
-INLINE void xor_block(uint8_t *out, const uint8_t *in1, const uint8_t* in2, size_t len)
+INLINE void xor_block_const_8(uint8_t *out,
+			const uint8_t *in, uint8_t k, size_t len)
 {
-	ASSERT(((size_t)in1 % 4) == 0);
-	ASSERT(((size_t)in2 % 4) == 0);
-	ASSERT(((size_t)out % 4) == 0);
-
-	const uint32_t *ibuf1 = (const uint32_t *)in1;
-	const uint32_t *ibuf2 = (const uint32_t *)in2;
-	uint32_t *obuf = (uint32_t *)out;
-	size_t rem = (len & 3);
-	
-	len /= 4;
 	while (len--)
-		*obuf++ = *ibuf1++ ^ *ibuf2++;
+                *out++ = *in++ ^ k;
+}
 
-	in1 = (const uint8_t*)ibuf1;
-	in2 = (const uint8_t*)ibuf2;
-	out = (uint8_t*)obuf;
-	while (rem--)	
+INLINE void xor_block_32(uint32_t *out, const uint32_t *in1,
+				const uint32_t *in2, size_t len)
+{
+	size_t rem = (len & (sizeof(uint32_t) - 1));
+
+	len /= sizeof(uint32_t);
+	while (len--)
 		*out++ = *in1++ ^ *in2++;
+	xor_block_8((uint8_t *)out,
+		(const uint8_t *)in1, (const uint8_t *)in2, rem);
 }
 
-INLINE void xor_block_const(uint8_t *out, const uint8_t *in, uint8_t k, size_t len)
+INLINE void xor_block_const_32(uint32_t *out, const uint32_t *in,
+					uint8_t k, size_t len)
 {
-	ASSERT(((size_t)in % 4) == 0);
-	ASSERT(((size_t)out % 4) == 0);
-
-	uint32_t k32 = k | ((uint32_t)k<<8) | ((uint32_t)k<<16) | ((uint32_t)k<<24);
-	const uint32_t *ibuf = (const uint32_t *)in;
-	uint32_t *obuf = (uint32_t *)out;
-	size_t rem = (len & 3);
-	
-	len /= 4;
+	uint32_t k32 = k | ((uint32_t)k << 8) |
+			((uint32_t)k << 16) | ((uint32_t)k << 24);
+	size_t rem = (len & (sizeof(uint32_t) - 1));
+
+	len /= sizeof(uint32_t);
 	while (len--)
-		*obuf++ = *ibuf++ ^ k32;
+		*out++ = *in++ ^ k32;
+	xor_block_const_8((uint8_t *)out, (const uint8_t *)in, k, rem);
+}
+
+/**
+ * Perform a bitwise xor between \a in and \a inout, and store
+ * the result into \a inout.
+ */
+INLINE void xor_block(void *out, const void *in1, const void *in2, size_t len)
+{
+	if (is_aligned(out, sizeof(uint32_t)) &&
+			is_aligned(in1, sizeof(uint32_t)) &&
+			is_aligned(in2, sizeof(uint32_t)))
+	{
+		uint32_t *obuf = (uint32_t *)((size_t)out);
+		const uint32_t *ibuf1 = (const uint32_t *)((size_t)in1);
+		const uint32_t *ibuf2 = (const uint32_t *)((size_t)in2);
+
+		xor_block_32(obuf, ibuf1, ibuf2, len);
+	}
+	else
+	{
+		uint8_t *obuf = (uint8_t *)((size_t)out);
+		const uint8_t *ibuf1 = (const uint8_t *)((size_t)in1);
+		const uint8_t *ibuf2 = (const uint8_t *)((size_t)in2);
 
-	in = (const uint8_t*)ibuf;
-	out = (uint8_t*)obuf;
-	while (rem--)	
-		*out++ = *in++ ^ k;
+		xor_block_8(obuf, ibuf1, ibuf2, len);
+	}
 }
 
-#endif
+/**
+ * Perform a bitwise xor over \a inout with constant \a k.
+ */
+INLINE void xor_block_const(uint8_t *out, const uint8_t *in, uint8_t k, size_t len)
+{
+	if (is_aligned(out, sizeof(uint32_t)) &&
+			is_aligned(in, sizeof(uint32_t)))
+	{
+		uint32_t *obuf = (uint32_t *)((size_t)out);
+		const uint32_t *ibuf = (const uint32_t *)((size_t)in);
+
+		xor_block_const_32(obuf, ibuf, k, len);
+	}
+	else
+	{
+		uint8_t *obuf = (uint8_t *)((size_t)out);
+		const uint8_t *ibuf = (const uint8_t *)((size_t)in);
+
+		xor_block_const_8(obuf, ibuf, k, len);
+	}
+}
 
 #endif /* SEC_UTIL_H */