diff options
author | Phil Sutter <phil@nwl.cc> | 2023-11-28 20:21:49 +0100 |
---|---|---|
committer | Phil Sutter <phil@nwl.cc> | 2023-11-29 02:33:06 +0100 |
commit | 41139aee5e53304182a25f1e573f034b313f7232 (patch) | |
tree | f102fe9cb362e3a6ba3c9a5adf48af3e8cc2b5a7 | |
parent | 584569727dc0fc52f401db628059807030138a99 (diff) |
libxtables: xtoptions: Fix for non-CIDR-compatible hostmasks
In order to parse the mask, xtopt_parse_hostmask() calls
xtopt_parse_plenmask() thereby limiting netmask support to prefix
lengths (alternatively specified in IP address notation).
In order to lift this impractical restriction, make
xtopt_parse_plenmask() aware of the fact that xtopt_parse_plen() may
fall back to xtopt_parse_mask() which correctly initializes val.hmask
itself and indicates non-CIDR-compatible masks by setting val.hlen to
-1.
So in order to support these odd masks, it is sufficient for
xtopt_parse_plenmask() to skip its mask building from val.hlen value and
take whatever val.hmask contains.
Fixes: 66266abd17adc ("libxtables: XTTYPE_HOSTMASK support")
Signed-off-by: Phil Sutter <phil@nwl.cc>
-rw-r--r-- | libxtables/xtoptions.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/libxtables/xtoptions.c b/libxtables/xtoptions.c index 64d740e3..5964a9bf 100644 --- a/libxtables/xtoptions.c +++ b/libxtables/xtoptions.c @@ -691,6 +691,10 @@ static void xtopt_parse_plenmask(struct xt_option_call *cb) xtopt_parse_plen(cb); + /* may not be convertible to CIDR notation */ + if (cb->val.hlen == (uint8_t)-1) + goto out_put; + memset(mask, 0xFF, sizeof(union nf_inet_addr)); /* This shifting is AF-independent. */ if (cb->val.hlen == 0) { @@ -711,6 +715,7 @@ static void xtopt_parse_plenmask(struct xt_option_call *cb) mask[1] = htonl(mask[1]); mask[2] = htonl(mask[2]); mask[3] = htonl(mask[3]); +out_put: if (entry->flags & XTOPT_PUT) memcpy(XTOPT_MKPTR(cb), mask, sizeof(union nf_inet_addr)); } |