log a warning when passwords would fail for being case-sensitive.

add a test to enforce the status quo, for now.

src/kernel/faction.c

@@ -313,7 +313,13 @@ unit *addplayer(region * r, faction * f)
 
 bool checkpasswd(const faction * f, const char *passwd)
 {
-    return (passwd && unicode_utf8_strcasecmp(f->passw, passwd) == 0);
+    if (!passwd) return false;
+    if (strcmp(f->passw, passwd)==0) return true;
+    if (unicode_utf8_strcasecmp(f->passw, passwd) == 0) {
+        log_warning("case-sensitive password check failed: %s", factionname(f));
+        return true;
+    }
+    return false;
 }
 
 variant read_faction_reference(struct storage * store)

src/kernel/faction.test.c

@@ -119,6 +119,16 @@ static void test_addfaction(CuTest *tc) {
     test_cleanup();
 }
 
+static void test_check_passwd(CuTest *tc) {
+    faction *f;
+    
+    f = test_create_faction(0);
+    faction_setpassword(f, "password");
+    CuAssertIntEquals(tc, true, checkpasswd(f, "password"));
+    CuAssertIntEquals(tc, true, checkpasswd(f, "PASSWORD"));
+    CuAssertIntEquals(tc, false, checkpasswd(f, "assword"));
+}
+
 static void test_get_monsters(CuTest *tc) {
     faction *f;
 
@@ -185,5 +195,6 @@ CuSuite *get_faction_suite(void)
     SUITE_ADD_TEST(suite, test_get_monsters);
     SUITE_ADD_TEST(suite, test_set_origin);
     SUITE_ADD_TEST(suite, test_set_origin_bug);
+    SUITE_ADD_TEST(suite, test_check_passwd);
     return suite;
 }