Address reviewer's comment

Don't allow "0xFF" in custom tags

Author: danielinux

tools/keytools/sign.c

@@ -2008,15 +2008,21 @@ int main(int argc, char** argv)
             tag = (uint16_t)arg2num(argv[i + 1], 2);
             len = (uint16_t)arg2num(argv[i + 2], 2);
 
-            if ((tag < 0x0030) || (tag > 0xFEFE)) {
+            if (tag < 0x0030) {
                 fprintf(stderr, "Invalid custom tag: %s\n", argv[i + 1]);
                 exit(16);
             }
+            if ( ((tag & 0xFF00) == 0xFF00) || ((tag & 0xFF) == 0xFF) ) {
+                fprintf(stderr, "Invalid custom tag: %s\n", argv[i + 1]);
+                exit(16);
+            }
+
             if ((len != 1) && (len != 2) && (len != 4) && (len != 8)) {
                 fprintf(stderr, "Invalid custom tag len: %s\n", argv[i + 2]);
                 fprintf(stderr, "Accepted len: 1, 2, 4 or 8\n");
                 exit(16);
             }
+
             CMD.custom_tlv[p].tag = tag;
             CMD.custom_tlv[p].len = len;
             CMD.custom_tlv[p].val = arg2num(argv[i+3], len);
@@ -2031,12 +2037,20 @@ int main(int argc, char** argv)
                 fprintf(stderr, "Too many custom TLVs.\n");
                 exit(16);
             }
-            if (argc < (i + 3)) {
+            if (argc < (i + 2)) {
                 fprintf(stderr, "Invalid custom TLV fields. \n");
                 exit(16);
             }
             tag = (uint16_t)arg2num(argv[i + 1], 2);
             len = (uint16_t)strlen(argv[i + 2]) / 2;
+            if (tag < 0x0030) {
+                fprintf(stderr, "Invalid custom tag: %s\n", argv[i + 1]);
+                exit(16);
+            }
+            if ( ((tag & 0xFF00) == 0xFF00) || ((tag & 0xFF) == 0xFF) ) {
+                fprintf(stderr, "Invalid custom tag: %s\n", argv[i + 1]);
+                exit(16);
+            }
             if (len > 255) {
                 fprintf(stderr, "custom tlv buffer size too big: %s\n", argv[i + 2]);
                 exit(16);