Cole Dishington <Cole.Dishington@xxxxxxxxxxxxxxxxxxx> wrote:
> Added --psid option to masquerade extension to specify port ranges, as
> described in RFC-7597 section 5.1. The PSID option needs the base field
> in range2, so add version 1 of the masquerade extension.
>
> Signed-off-by: Cole Dishington <Cole.Dishington@xxxxxxxxxxxxxxxxxxx>
> ---
> extensions/libipt_MASQUERADE.c | 283 +++++++++++++++++++++++++------
> include/linux/netfilter/nf_nat.h | 5 +-
Can you add test cases too?
( extensions/libipt_MASQUERADE.t ).
The new option needs to be added to the man page as well that briefly
explains what its doing and what the --psid numbers do (ports? bits?).
> +static void MASQUERADE_help_v1(void)
> +{
> + printf(
> +"MASQUERADE target options:\n"
> +" --to-ports <port>[-<port>]\n"
> +" Port (range) to map to.\n"
> +" --random\n"
> +" Randomize source port.\n"
> +" --random-fully\n"
> +" Fully randomize source port.\n"
Consider removing the above, you can just call
MASQUERADE_help() before printf(" --psid ...
> +static void range_to_psid_args(struct nf_nat_range2 *r, unsigned int *offset,
> + unsigned int *psid, unsigned int *psid_length)
> +{
warning: passing argument 1 of 'range_to_psid_args' discards 'const'
qualifier from pointer target type [-Wdiscarded-qualifiers]
239 | range_to_psid_args(r, &offset, &psid, &psid_length);
> + min = htons(r->min_proto.all);
> + power_j = htons(r->max_proto.all) - min + 1;
> + *offset = ntohs(r->base_proto.all);
> + *psid = (min - *offset) >> _log2(power_j);
> + *psid_length = _log2(*offset/power_j);
> +}
> +
> +static void parse_psid(const char *arg, struct nf_nat_range2 *r)
> +{
> + char *end;
> + unsigned int offset, psid, psid_len;
> +
> + if (!xtables_strtoui(arg, &end, &offset, 0, UINT16_MAX) || *end != ':' ||
> + offset >= (1 << 16))
> + xtables_param_act(XTF_BAD_VALUE, "MASQUERADE", "PSID settings", arg);
> +
> + if (!xtables_strtoui(end + 1, &end, &psid, 0, UINT16_MAX) || *end != ':')
> + xtables_param_act(XTF_BAD_VALUE, "MASQUERADE", "PSID settings", arg);
> +
> + if (!xtables_strtoui(end + 1, &end, &psid_len, 0, UINT16_MAX) || *end != '\0' ||
> + psid_len >= 16)
> + xtables_param_act(XTF_BAD_VALUE, "MASQUERADE", "PSID settings", arg);
This needs better error checking. For example, this should
say which of the parameters (offset,len, ...) causes the parse error.
> + psid = psid << (_log2(offset/(1 << psid_len)));
This results in infinite _log2() loop if offset / 1 << len is 0.
