Réécriture des commentaires schématiques sur les tweaks

1 files changed, 16 insertions, 12 deletions

diff --git a/src/ref/lilliput-i.c b/src/ref/lilliput-i.c
index fb06237..3358b10 100644
--- a/src/ref/lilliput-i.c
+++ b/src/ref/lilliput-i.c
@@ -44,13 +44,15 @@ static uint8_t _lower_nibble(uint8_t i)
 
 static void _init_msg_tweak(const uint8_t N[NONCE_BYTES], uint8_t tweak[TWEAK_BYTES])
 {
-    /* With an s-bit block index, the t-bit tweak is filled as follows:
+    /* The t-bit tweak is filled as follows:
      *
-     * [     1,     4]: 4-bit prefix
-     * [     5, |N|+4]: nonce
-     * [ |N|+5,     t]: block index
-     *  [|N|+5,   t-s]: 0-padding
-     *  [t-s+1,     t]: actual block index, from MSB to LSB
+     *   1    4    5     |N|+4    |N|+5     t
+     * [ prefix ||  nonce      || block index ]
+     *
+     * The s-bit block index is encoded as follows:
+     *
+     *   |N|+5    t-s    t-s+1                t
+     * [ zero padding || block index, MSB first ]
      *
      * This function sets bits 5 to t-s once and for all.
      */
@@ -77,13 +79,15 @@ static void _fill_msg_tweak(
     uint8_t tweak[TWEAK_BYTES]
 )
 {
-    /* With an s-bit block index, the t-bit tweak is filled as follows:
+    /* The t-bit tweak is filled as follows:
+     *
+     *   1    4    5     |N|+4    |N|+5     t
+     * [ prefix ||  nonce      || block index ]
+     *
+     * The s-bit block index is encoded as follows:
      *
-     * [     1,     4]: 4-bit prefix
-     * [     5, |N|+4]: nonce
-     * [ |N|+5,     t]: block index
-     *  [|N|+5,   t-s]: 0-padding
-     *  [t-s+1,     t]: actual block index, from MSB to LSB
+     *   |N|+5    t-s    t-s+1                t
+     * [ zero padding || block index, MSB first ]
      *
      * This function assumes bits 5 to t-s have already been set, and
      * only sets bits 1 to 4 and t-s+1 to t.