From 257c18bf4fbcc7e5f4fb3c9cadab699986a9bd41 Mon Sep 17 00:00:00 2001 From: Phil Sutter Date: Wed, 16 Mar 2022 17:14:07 +0100 Subject: [PATCH] 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 (cherry picked from commit b1aee6b2238794446feba41778f88703784560f7) Conflicts: iptables/xshared.c -> Parts manually applied due to unmerged do_parse() function. --- iptables/ip6tables.c | 2 +- iptables/iptables.c | 2 +- iptables/xshared.c | 2 +- iptables/xshared.h | 2 +- iptables/xtables-restore.c | 5 +---- iptables/xtables.c | 2 +- 6 files changed, 6 insertions(+), 9 deletions(-) diff --git a/iptables/ip6tables.c b/iptables/ip6tables.c index 614d1e249c06d..b96dc033e7ebb 100644 --- a/iptables/ip6tables.c +++ b/iptables/ip6tables.c @@ -1247,7 +1247,7 @@ int do_command6(int argc, char *argv[], char **table, break; case 'N': - parse_chain(optarg); + assert_valid_chain_name(optarg); add_command(&command, CMD_NEW_CHAIN, CMD_NONE, cs.invert); chain = optarg; diff --git a/iptables/iptables.c b/iptables/iptables.c index 3b395981cc8ea..6e2946f5660de 100644 --- a/iptables/iptables.c +++ b/iptables/iptables.c @@ -1243,7 +1243,7 @@ int do_command4(int argc, char *argv[], char **table, break; case 'N': - parse_chain(optarg); + assert_valid_chain_name(optarg); add_command(&command, CMD_NEW_CHAIN, CMD_NONE, cs.invert); chain = optarg; diff --git a/iptables/xshared.c b/iptables/xshared.c index de8326b6c7b05..0c232ca2ae8d5 100644 --- a/iptables/xshared.c +++ b/iptables/xshared.c @@ -776,7 +776,7 @@ int parse_rulenumber(const char *rule) return rulenum; } -void parse_chain(const char *chainname) +void assert_valid_chain_name(const char *chainname) { const char *ptr; diff --git a/iptables/xshared.h b/iptables/xshared.h index f5d2f8d0a2bc5..095a574d85879 100644 --- a/iptables/xshared.h +++ b/iptables/xshared.h @@ -217,6 +217,6 @@ 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); #endif /* IPTABLES_XSHARED_H */ diff --git a/iptables/xtables-restore.c b/iptables/xtables-restore.c index c472ac9bf651b..a078da32045dc 100644 --- a/iptables/xtables-restore.c +++ b/iptables/xtables-restore.c @@ -150,10 +150,7 @@ 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); diff --git a/iptables/xtables.c b/iptables/xtables.c index 3ea293ee7c411..9006962472c58 100644 --- a/iptables/xtables.c +++ b/iptables/xtables.c @@ -668,7 +668,7 @@ void do_parse(struct nft_handle *h, int argc, char *argv[], break; case 'N': - parse_chain(optarg); + assert_valid_chain_name(optarg); add_command(&p->command, CMD_NEW_CHAIN, CMD_NONE, cs->invert); p->chain = optarg; -- 2.34.1