Merge pull request #15 from oroderico/drop-unreachable-checksum-notice

Drop the checksum notice the last-word filter made unreachable

Author: oroderico

README.md

@@ -370,11 +370,11 @@ the checksum, so most of the wordlist cannot end a given eleven or twenty-three:
 its eleven bits are the leftover entropy bits followed by the checksum bits,
 which leaves 128 of the 2048 words possible for a 12-word mnemonic and only 8
 for a 24-word one. The keyboard offers those and nothing else — so a word misread
-off a metal plate is not typeable in the first place, rather than being reported
-as `Invalid checksum` after the whole mnemonic has been entered. Few enough
-remain for a 24-word restore that entry lists them outright instead of asking
-for a letter. The narrowing is exact in both directions: everything it excludes
-genuinely fails validation, and no correct seed becomes harder to enter. It
+off a metal plate is not typeable in the first place, rather than being refused
+after the whole mnemonic has been entered. Few enough remain for a 24-word
+restore that entry lists them outright instead of asking for a letter. The
+narrowing is exact in both directions: everything it excludes genuinely fails
+validation, and no correct seed becomes harder to enter. It
 applies to both entry methods and to the last word on the review screen, where
 it is rebuilt from the words currently entered — but not to "Complete checksum",
 whose 11 or 23 words have no checksum in them yet, and not to the backup quiz,

host/origo_simulator.c

@@ -1789,7 +1789,6 @@ static bool nav_chrome_bands_do_not_collide(void)
         const char* line1;
         const char* line2;
     } notices[] = {
-        { "Invalid checksum", "Check your words", "Fix one to continue" },
         { "Passphrase mismatch", "Nothing was derived", "Try again" },
         { "Backup confirmed", "Words matched", NULL },
         { "Too long for a QR", "Compact SeedQR", "Read it as text instead" },

main/seedtool_app.c

@@ -1713,16 +1713,21 @@ static int revisit_prefix(char words[][SEEDTOOL_MAX_WORD_LEN + 1], const size_t
  * seedtool_validate_mnemonic yet - the checksum gate belongs only where the
  * mnemonic is meant to be whole and correct, which is why that flow reviews
  * through review_prefix instead.
- * join_words and seedtool_validate_mnemonic are the same pair review_and_
- * confirm itself calls every time it redraws; reused once more here, before
- * the first draw, so an invalid checksum is announced up front rather than
- * only implied by "Review words" silently reading "Review - fix a word"
- * instead - the inert "Checksum invalid" row this screen used to carry (see
- * "Drop the inert 'Checksum invalid' row from word review") was removed for
- * being a dead click, not because the reader shouldn't be told; a one-shot
- * acknowledge, the same widget restore_seed's own "Checksum valid" already
- * uses for the opposite verdict, says it without adding a row that does
- * nothing when picked. */
+ *
+ * No checksum is announced here, and the absence is deliberate: there is
+ * nothing left for it to announce. The last word of a whole mnemonic is
+ * entered under seedtool_final_word_candidates, both keyboards narrow to that
+ * set rather than merely displaying it, and stepping back clears the word so
+ * the last one is always entered last against a filter rebuilt from the words
+ * currently standing. What leaves enter_mnemonic_words with success has a
+ * checksum that holds.
+ *
+ * A one-shot notice did stand here, from before that filter existed, and its
+ * own commit said the check was being moved to where it prevents the mistake
+ * instead of reporting it. Only the moving happened. Restoring it would mean
+ * restoring a screen no input can reach - and the reader is not left without a
+ * gate either way, since review_and_confirm still reads the checksum on every
+ * redraw and keeps Continue untakeable while it fails. */
 static int restore_mnemonic(const size_t count, char words[][SEEDTOOL_MAX_WORD_LEN + 1], bool* const by_number,
     char* mnemonic, const size_t mnemonic_len, bool resume)
 {
@@ -1737,10 +1742,6 @@ static int restore_mnemonic(const size_t count, char words[][SEEDTOOL_MAX_WORD_L
             if (entered != 1) {
                 return entered;
             }
-            if (join_words(words, count, mnemonic, mnemonic_len)
-                && seedtool_validate_mnemonic(mnemonic, NULL) != SEEDTOOL_OK) {
-                notice("Invalid checksum", "Check your words", "Fix one to continue");
-            }
         }
         resume = false;
         const int reviewed = review_and_confirm(words, count, *by_number, mnemonic, mnemonic_len);