Changeset 5530:9aa578adc5bd in roaraudio

Timestamp:

06/12/12 09:26:41 (11 years ago)

Author:

phi

Branch:

default

Phase:

public

Message:

strengthened hash support against memory analyzing attacks

Location:

libroar

Files:

• hash.c (modified) (1 diff)
• hash_sha1.c (modified) (2 diffs)
• hash_tiger.c (modified) (2 diffs)

libroar/hash.c

@@ -372 +372 @@
   ret = state->cmds->uninit(state->state);
 
+ // clear crypto data.
+ memset(state->state, 0, state->cmds->statelen);
+ memset(state, 0, sizeof(struct roar_hash_state));
+
  roar_mm_free(state->state);
  roar_mm_free(state);

libroar/hash_sha1.c

@@ -133 +133 @@
  roar_hash_sha1_proc(state, &count, 8);
 
- context->is_final = 1;
 
  for (i = 0; i < SHA1_DIGEST_LENGTH; i++) {
@@ -140 +139 @@
 
  memset(context, 0, sizeof(struct roar_hash_sha1));
+ context->is_final = 1;
 
  return 0;

libroar/hash_tiger.c

@@ -725 +725 @@
 
 static void tiger_round( uint64_t * ra, uint64_t * rb, uint64_t * rc, uint64_t x, uint64_t mul) {
-  uint64_t a = *ra;
-  uint64_t b = *rb;
-  uint64_t c = *rc;
-
-  c ^= x;
-  a -= (  sbox1[  c        & 0xff ] ^ sbox2[ (c >> 16) & 0xff ]
-        ^ sbox3[ (c >> 32) & 0xff ] ^ sbox4[ (c >> 48) & 0xff ]);
-  b += (  sbox4[ (c >>  8) & 0xff ] ^ sbox3[ (c >> 24) & 0xff ]
-        ^ sbox2[ (c >> 40) & 0xff ] ^ sbox1[ (c >> 56) & 0xff ]);
-  b *= mul;
-
-  *ra = a;
-  *rb = b;
-  *rc = c;
+ uint64_t a = *ra;
+ uint64_t b = *rb;
+ uint64_t c = *rc;
+
+ c ^= x;
+ a -= (  sbox1[  c        & 0xff ] ^ sbox2[ (c >> 16) & 0xff ]
+       ^ sbox3[ (c >> 32) & 0xff ] ^ sbox4[ (c >> 48) & 0xff ]);
+ b += (  sbox4[ (c >>  8) & 0xff ] ^ sbox3[ (c >> 24) & 0xff ]
+       ^ sbox2[ (c >> 40) & 0xff ] ^ sbox1[ (c >> 56) & 0xff ]);
+ b *= mul;
+
+ *ra = a;
+ *rb = b;
+ *rc = c;
+
+ a = b = c = 0;
 }
 
@@ -824 +826 @@
  state->blocks++;
 
+ a = b = c = aa = bb = cc = 0;
+
  ROAR_DBG("roar_hash_tiger_proc_block(state=%p, block=%p) = 0", state, block);
  return 0;