highlighter: insist on 256-bit keys, not 257-bit or 258-bit

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

diff --git a/WireGuard/WireGuard/UI/macOS/View/highlighter.c b/WireGuard/WireGuard/UI/macOS/View/highlighter.c
index 171a84c97066a4e8fa1f9a046660a0d5b65080eb..e0d4e04e9abde062eab2b839168f22704a74fa9d 100644 (file)
--- a/WireGuard/WireGuard/UI/macOS/View/highlighter.c
+++ b/WireGuard/WireGuard/UI/macOS/View/highlighter.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0
 /*
- * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ * Copyright (C) 2015-2020 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
  */
 
 #include <stdbool.h>
@@ -62,11 +62,32 @@ static bool is_valid_key(string_span_t s)
        if (s.len != 44 || s.s[43] != '=')
                return false;
 
-       for (size_t i = 0; i < 43; ++i) {
+       for (size_t i = 0; i < 42; ++i) {
                if (!is_decimal(s.s[i]) && !is_alphabet(s.s[i]) &&
                    s.s[i] != '/' && s.s[i] != '+')
                        return false;
        }
+       switch (s.s[42]) {
+       case 'A':
+       case 'E':
+       case 'I':
+       case 'M':
+       case 'Q':
+       case 'U':
+       case 'Y':
+       case 'c':
+       case 'g':
+       case 'k':
+       case 'o':
+       case 's':
+       case 'w':
+       case '4':
+       case '8':
+       case '0':
+               break;
+       default:
+               return false;
+       }
        return true;
 }
 
@@ -166,9 +187,9 @@ static bool is_valid_uint(string_span_t s, bool support_hex, uint64_t min, uint6
 
        if (support_hex && s.len > 2 && s.s[0] == '0' && s.s[1] == 'x') {
                for (size_t i = 2; i < s.len; ++i) {
-                       if (s.s[i] - '0' < 10)
+                       if ((unsigned)s.s[i] - '0' < 10)
                                val = 16 * val + (s.s[i] - '0');
-                       else if ((s.s[i] | 32) - 'a' < 6)
+                       else if (((unsigned)s.s[i] | 32) - 'a' < 6)
                                val = 16 * val + (s.s[i] | 32) - 'a' + 10;
                        else
                                return false;