At the moment, status_xlate_print function prints statusmask as comma-separated
sequence of enabled statusmask flags. But if we have inverted conntrack ctstatus
condition then we have to use more complex expression (if more than one flag enabled)
because nft not supports syntax like "ct status != expected,assured".
Examples:
! --ctstatus CONFIRMED,ASSURED
should be translated as
ct status & (assured|confirmed) == 0
! --ctstatus CONFIRMED
can be translated as
ct status != confirmed
See also netfilter/xt_conntrack.c (conntrack_mt() function as a reference).
Reproducer:
$ iptables -A INPUT -d 127.0.0.1/32 -p tcp -m conntrack ! --ctstatus expected,assured -j DROP
$ nft list ruleset
...
meta l4proto tcp ip daddr 127.0.0.1 ct status != expected,assured counter packets 0 bytes 0 drop
...
it will fail if we try to load this rule:
$ nft -f nft_test
../nft_test:6:97-97: Error: syntax error, unexpected comma, expecting newline or semicolon
Cc: Florian Westphal <fw@xxxxxxxxx>
Signed-off-by: Alexander Mikhalitsyn <alexander.mikhalitsyn@xxxxxxxxxxxxx>
---
extensions/libxt_conntrack.c | 28 +++++++++++++++++++---------
extensions/libxt_conntrack.txlate | 6 ++++++
2 files changed, 25 insertions(+), 9 deletions(-)
diff --git a/extensions/libxt_conntrack.c b/extensions/libxt_conntrack.c
index fe964aa..48e7415 100644
--- a/extensions/libxt_conntrack.c
+++ b/extensions/libxt_conntrack.c
@@ -1198,26 +1198,37 @@ static int state_xlate(struct xt_xlate *xl,
return 1;
}
-static void status_xlate_print(struct xt_xlate *xl, unsigned int statusmask)
+static void status_xlate_print(struct xt_xlate *xl, unsigned int statusmask, int inverted)
{
const char *sep = "";
+ int one_flag_set;
+
+ one_flag_set = !(statusmask & (statusmask - 1));
+
+ if (inverted && !one_flag_set)
+ xt_xlate_add(xl, "& (");
+ else if (inverted)
+ xt_xlate_add(xl, "!= ");
if (statusmask & IPS_EXPECTED) {
xt_xlate_add(xl, "%s%s", sep, "expected");
- sep = ",";
+ sep = inverted && !one_flag_set ? "|" : ",";
}
if (statusmask & IPS_SEEN_REPLY) {
xt_xlate_add(xl, "%s%s", sep, "seen-reply");
- sep = ",";
+ sep = inverted && !one_flag_set ? "|" : ",";
}
if (statusmask & IPS_ASSURED) {
xt_xlate_add(xl, "%s%s", sep, "assured");
- sep = ",";
+ sep = inverted && !one_flag_set ? "|" : ",";
}
if (statusmask & IPS_CONFIRMED) {
xt_xlate_add(xl, "%s%s", sep, "confirmed");
- sep = ",";
+ sep = inverted && !one_flag_set ? "|" : ",";
}
+
+ if (inverted && !one_flag_set)
+ xt_xlate_add(xl, ") == 0");
}
static void addr_xlate_print(struct xt_xlate *xl,
@@ -1277,10 +1288,9 @@ static int _conntrack3_mt_xlate(struct xt_xlate *xl,
}
if (sinfo->match_flags & XT_CONNTRACK_STATUS) {
- xt_xlate_add(xl, "%sct status %s", space,
- sinfo->invert_flags & XT_CONNTRACK_STATUS ?
- "!= " : "");
- status_xlate_print(xl, sinfo->status_mask);
+ xt_xlate_add(xl, "%sct status ", space);
+ status_xlate_print(xl, sinfo->status_mask,
+ sinfo->invert_flags & XT_CONNTRACK_STATUS);
space = " ";
}
diff --git a/extensions/libxt_conntrack.txlate b/extensions/libxt_conntrack.txlate
index 75b3daa..3939d00 100644
--- a/extensions/libxt_conntrack.txlate
+++ b/extensions/libxt_conntrack.txlate
@@ -37,6 +37,12 @@ nft add rule ip filter INPUT ct status expected counter accept
iptables-translate -t filter -A INPUT -m conntrack ! --ctstatus CONFIRMED -j ACCEPT
nft add rule ip filter INPUT ct status != confirmed counter accept
+iptables-translate -t filter -A INPUT -m conntrack ! --ctstatus CONFIRMED,ASSURED -j ACCEPT
+nft add rule ip filter INPUT ct status & (assured|confirmed) == 0 counter accept
+
+iptables-translate -t filter -A INPUT -m conntrack --ctstatus CONFIRMED,ASSURED -j ACCEPT
+nft add rule ip filter INPUT ct status assured,confirmed counter accept
+
iptables-translate -t filter -A INPUT -m conntrack --ctexpire 3 -j ACCEPT
nft add rule ip filter INPUT ct expiration 3 counter accept
--
1.8.3.1
