diff --git a/extensions/generic.txlate b/extensions/generic.txlate index b38fbd1..c92d082 100644 --- a/extensions/generic.txlate +++ b/extensions/generic.txlate @@ -18,3 +18,15 @@ nft add rule bridge filter FORWARD iifname != "iname" meta ibrname "ilogname" oi ebtables-translate -I INPUT -p ip -d 1:2:3:4:5:6/ff:ff:ff:ff:00:00 nft insert rule bridge filter INPUT ether type 0x800 ether daddr 01:02:03:04:00:00 and ff:ff:ff:ff:00:00 == 01:02:03:04:00:00 counter + +# asterisk is not special in iptables and it is even a valid interface name +iptables-translate -A FORWARD -i '*' -o 'eth*foo' +nft add rule ip filter FORWARD iifname "\*" oifname "eth\*foo" counter + +# skip for always matching interface names +iptables-translate -A FORWARD -i '+' +nft add rule ip filter FORWARD counter + +# match against invalid interface name to simulate never matching rule +iptables-translate -A FORWARD ! -i '+' +nft add rule ip filter FORWARD iifname "INVAL/D" counter diff --git a/iptables/xtables-translate.c b/iptables/xtables-translate.c index 77a186b..c4e177c 100644 --- a/iptables/xtables-translate.c +++ b/iptables/xtables-translate.c @@ -32,15 +32,38 @@ void xlate_ifname(struct xt_xlate *xl, const char *nftmeta, const char *ifname, bool invert) { - int ifaclen = strlen(ifname); - char iface[IFNAMSIZ]; + int ifaclen = strlen(ifname), i, j; + char iface[IFNAMSIZ * 2]; if (ifaclen < 1 || ifaclen >= IFNAMSIZ) return; - strcpy(iface, ifname); - if (iface[ifaclen - 1] == '+') - iface[ifaclen - 1] = '*'; + for (i = 0, j = 0; i < ifaclen + 1; i++, j++) { + switch (ifname[i]) { + case '+': + iface[j] = '*'; + break; + case '*': + iface[j++] = '\\'; + /* fall through */ + default: + iface[j] = ifname[i]; + break; + } + } + + if (ifaclen == 1 && ifname[0] == '+') { + /* Nftables does not support wildcard only string. Workaround + * is easy, given that this will match always or never + * depending on 'invert' value. To match always, simply don't + * generate an expression. To match never, use an invalid + * interface name (kernel doesn't accept '/' in names) to match + * against. */ + if (!invert) + return; + strcpy(iface, "INVAL/D"); + invert = false; + } xt_xlate_add(xl, "%s %s\"%s\" ", nftmeta, invert ? "!= " : "", iface); }