On Wed, 28 Sep 2022 14:33:12 +1000
David Gibson <david(a)gibson.dropbear.id.au> wrote:
conf_ports() parses ranges of ports for the -t,
-u, -T and -U options.
The code is quite difficult to the follow, to the point that clang-tidy
and cppcheck disagree on whether one of the pointers can be NULL at some
points.
Rework the code with the use of two new helper functions:
* parse_port_range() operates a bit like strtoul(), but can parse a whole
port range specification (e.g. '80' or '1000-1015')
* next_chunk() does the necessary wrapping around strchr() to advance to
just after the next given delimiter, while cleanly handling if there
are no more delimiters
The new version is easier to follow,
Indeed. Just one excess whitespace:
[...]
+ if (*p == ':') { /* There's a range to map to as well */
+ if (parse_port_range(p + 1, &p, &mapped_range))
goto bad;
-
- if (start_dst > end_dst) /* 22-80:8080:8022 */
+ if ((mapped_range.last - mapped_range.first) !=
+ (orig_range.last - orig_range.first))
goto bad;
+ } else {
+ mapped_range = orig_range;
+ }
- if (end_dst != -1 &&
- end_dst - start_dst != end_src - start_src)
- goto bad; /* 22-81:8022:8080 */
-
- for (i = start_src; i <= end_src; i++) {
- if (bitmap_isset(fwd->map, i))
- goto overlap;
+ if ((*p != '\0') && (*p != ',')) /* Garbage after the
ranges */
...here. I can drop it myself.