From b1aee6b2238794446feba41778f88703784560f7 Mon Sep 17 00:00:00 2001 From: Phil Sutter Date: Wed, 16 Mar 2022 17:14:07 +0100 Subject: nft: Reject standard targets as chain names when restoring Reuse parse_chain() called from do_parse() for '-N' and rename it for a better description of what it does. Note that by itself, this patch will likely kill iptables-restore performance for big rulesets due to the extra extension lookup for chain lines. A following patch announcing those chains to libxtables will alleviate that. Signed-off-by: Phil Sutter Reviewed-by: Florian Westphal --- iptables/xshared.c | 4 ++-- iptables/xshared.h | 2 +- iptables/xtables-restore.c | 5 +---- 3 files changed, 4 insertions(+), 7 deletions(-) diff --git a/iptables/xshared.c b/iptables/xshared.c index 43321d3b..00828c8a 100644 --- a/iptables/xshared.c +++ b/iptables/xshared.c @@ -1031,7 +1031,7 @@ set_option(unsigned int *options, unsigned int option, u_int16_t *invflg, } } -void parse_chain(const char *chainname) +void assert_valid_chain_name(const char *chainname) { const char *ptr; @@ -1412,7 +1412,7 @@ void do_parse(int argc, char *argv[], break; case 'N': - parse_chain(optarg); + assert_valid_chain_name(optarg); add_command(&p->command, CMD_NEW_CHAIN, CMD_NONE, invert); p->chain = optarg; diff --git a/iptables/xshared.h b/iptables/xshared.h index 0de0e12e..ca761ee7 100644 --- a/iptables/xshared.h +++ b/iptables/xshared.h @@ -244,7 +244,7 @@ char cmd2char(int option); void add_command(unsigned int *cmd, const int newcmd, const int othercmds, int invert); int parse_rulenumber(const char *rule); -void parse_chain(const char *chainname); +void assert_valid_chain_name(const char *chainname); void generic_opt_check(int command, int options); char opt2char(int option); diff --git a/iptables/xtables-restore.c b/iptables/xtables-restore.c index b3cf4017..b70a3cb1 100644 --- a/iptables/xtables-restore.c +++ b/iptables/xtables-restore.c @@ -155,10 +155,7 @@ static void xtables_restore_parse_line(struct nft_handle *h, "%s: line %u chain name invalid\n", xt_params->program_name, line); - if (strlen(chain) >= XT_EXTENSION_MAXNAMELEN) - xtables_error(PARAMETER_PROBLEM, - "Invalid chain name `%s' (%u chars max)", - chain, XT_EXTENSION_MAXNAMELEN - 1); + assert_valid_chain_name(chain); policy = strtok(NULL, " \t\n"); DEBUGP("line %u, policy '%s'\n", line, policy); -- cgit v1.2.3