diff options
| -rw-r--r-- | extensions/libxt_tcpmss.c | 92 |
1 files changed, 20 insertions, 72 deletions
diff --git a/extensions/libxt_tcpmss.c b/extensions/libxt_tcpmss.c index 3dc35286..c7c59717 100644 --- a/extensions/libxt_tcpmss.c +++ b/extensions/libxt_tcpmss.c @@ -1,14 +1,11 @@ -/* Shared library add-on to iptables to add tcp MSS matching support. */ -#include <stdbool.h> #include <stdio.h> -#include <netdb.h> -#include <string.h> -#include <stdlib.h> -#include <getopt.h> - #include <xtables.h> #include <linux/netfilter/xt_tcpmss.h> +enum { + O_TCPMSS = 0, +}; + static void tcpmss_help(void) { printf( @@ -17,71 +14,23 @@ static void tcpmss_help(void) " (only valid for TCP SYN or SYN/ACK packets)\n"); } -static const struct option tcpmss_opts[] = { - {.name = "mss", .has_arg = true, .val = '1'}, - XT_GETOPT_TABLEEND, +static const struct xt_option_entry tcpmss_opts[] = { + {.name = "mss", .id = O_TCPMSS, .type = XTTYPE_UINT16RC, + .flags = XTOPT_MAND | XTOPT_INVERT}, + XTOPT_TABLEEND, }; -static uint16_t -parse_tcp_mssvalue(const char *mssvalue) -{ - unsigned int mssvaluenum; - - if (xtables_strtoui(mssvalue, NULL, &mssvaluenum, 0, UINT16_MAX)) - return mssvaluenum; - - xtables_error(PARAMETER_PROBLEM, - "Invalid mss `%s' specified", mssvalue); -} - -static void -parse_tcp_mssvalues(const char *mssvaluestring, - uint16_t *mss_min, uint16_t *mss_max) -{ - char *buffer; - char *cp; - - buffer = strdup(mssvaluestring); - if ((cp = strchr(buffer, ':')) == NULL) - *mss_min = *mss_max = parse_tcp_mssvalue(buffer); - else { - *cp = '\0'; - cp++; - - *mss_min = buffer[0] ? parse_tcp_mssvalue(buffer) : 0; - *mss_max = cp[0] ? parse_tcp_mssvalue(cp) : 0xFFFF; - } - free(buffer); -} - -static int -tcpmss_parse(int c, char **argv, int invert, unsigned int *flags, - const void *entry, struct xt_entry_match **match) -{ - struct xt_tcpmss_match_info *mssinfo = - (struct xt_tcpmss_match_info *)(*match)->data; - - switch (c) { - case '1': - if (*flags) - xtables_error(PARAMETER_PROBLEM, - "Only one `--mss' allowed"); - xtables_check_inverse(optarg, &invert, &optind, 0, argv); - parse_tcp_mssvalues(optarg, - &mssinfo->mss_min, &mssinfo->mss_max); - if (invert) - mssinfo->invert = 1; - *flags = 1; - break; - } - return 1; -} - -static void tcpmss_check(unsigned int flags) +static void tcpmss_parse(struct xt_option_call *cb) { - if (!flags) - xtables_error(PARAMETER_PROBLEM, - "tcpmss match: You must specify `--mss'"); + struct xt_tcpmss_match_info *mssinfo = cb->data; + + xtables_option_parse(cb); + mssinfo->mss_min = cb->val.u16_range[0]; + mssinfo->mss_max = mssinfo->mss_min; + if (cb->nvals == 2) + mssinfo->mss_max = cb->val.u16_range[1]; + if (cb->invert) + mssinfo->invert = 1; } static void @@ -114,11 +63,10 @@ static struct xtables_match tcpmss_match = { .size = XT_ALIGN(sizeof(struct xt_tcpmss_match_info)), .userspacesize = XT_ALIGN(sizeof(struct xt_tcpmss_match_info)), .help = tcpmss_help, - .parse = tcpmss_parse, - .final_check = tcpmss_check, .print = tcpmss_print, .save = tcpmss_save, - .extra_opts = tcpmss_opts, + .x6_parse = tcpmss_parse, + .x6_options = tcpmss_opts, }; void _init(void) |