From ba1c0fe89eb56f8bf25f9165f2e5dc366ea0118c Mon Sep 17 00:00:00 2001 From: Phil Sutter Date: Thu, 1 Dec 2022 15:16:43 +0100 Subject: xtables-translate: Fix for interfaces with asterisk mid-string For nft, asterisk is special at end of the interface name only. Escaping it mid-string makes the escape char part of the interface name, so avoid this. In the test case, also drop the ticks around interface names in *-translate command - since there's no shell involved which would eat them, they become part of the interface name. Fixes: e179e87a1179e ("xtables-translate: Fix for interface name corner-cases") Signed-off-by: Phil Sutter --- extensions/generic.txlate | 14 +++++++------- iptables/xtables-translate.c | 4 +++- 2 files changed, 10 insertions(+), 8 deletions(-) diff --git a/extensions/generic.txlate b/extensions/generic.txlate index 7e879fd5..d7ddf6a3 100644 --- a/extensions/generic.txlate +++ b/extensions/generic.txlate @@ -74,17 +74,17 @@ ebtables-translate -I INPUT -p ! Length nft 'insert rule bridge filter INPUT ether type >= 0x0600 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' +iptables-translate -A FORWARD -i * -o eth*foo +nft 'add rule ip filter FORWARD iifname "\*" oifname "eth*foo" counter' -# escape all asterisks but translate only the first plus character -iptables-translate -A FORWARD -i 'eth*foo*+' -o 'eth++' -nft 'add rule ip filter FORWARD iifname "eth\*foo\**" oifname "eth+*" counter' +# escape only suffix asterisk and translate only the last plus character +iptables-translate -A FORWARD -i eth*foo*+ -o eth++ +nft 'add rule ip filter FORWARD iifname "eth*foo**" oifname "eth+*" counter' # skip for always matching interface names -iptables-translate -A FORWARD -i '+' +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 '+' +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 102973a6..22b2fbc8 100644 --- a/iptables/xtables-translate.c +++ b/iptables/xtables-translate.c @@ -41,7 +41,9 @@ void xlate_ifname(struct xt_xlate *xl, const char *nftmeta, const char *ifname, for (i = 0, j = 0; i < ifaclen + 1; i++, j++) { switch (ifname[i]) { case '*': - iface[j++] = '\\'; + /* asterisk is non-special mid-string */ + if (i == ifaclen - 1) + iface[j++] = '\\'; /* fall through */ default: iface[j] = ifname[i]; -- cgit v1.2.3