diff options
Diffstat (limited to 'extensions/libipt_2tos.c')
-rw-r--r-- | extensions/libipt_2tos.c | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/extensions/libipt_2tos.c b/extensions/libipt_2tos.c new file mode 100644 index 00000000..49dbac55 --- /dev/null +++ b/extensions/libipt_2tos.c @@ -0,0 +1,172 @@ +/* Shared library add-on to iptables to add TOS matching support. */ +#include <stdio.h> +#include <netdb.h> +#include <string.h> +#include <stdlib.h> +#include <getopt.h> + +#include <iptables.h> +#include <linux/netfilter_ipv4/ipt_tos_.h> + +/* TOS names and values. */ +static +struct TOS_value +{ + unsigned char TOS; + const char *name; +} TOS_values[] = { + { IPTOS_LOWDELAY, "Minimize-Delay" }, + { IPTOS_THROUGHPUT, "Maximize-Throughput" }, + { IPTOS_RELIABILITY, "Maximize-Reliability" }, + { IPTOS_MINCOST, "Minimize-Cost" }, + { IPTOS_NORMALSVC, "Normal-Service" }, +}; + +/* Function which prints out usage message. */ +static void +help(void) +{ + unsigned int i; + + printf( +"TOS match v%s options:\n" +"[!] --tos value Match Type of Service field from one of the\n" +" following numeric or descriptive values:\n", +IPTABLES_VERSION); + + for (i = 0; i < sizeof(TOS_values)/sizeof(struct TOS_value);i++) + printf(" %s %u (0x%02x)\n", + TOS_values[i].name, + TOS_values[i].TOS, + TOS_values[i].TOS); + fputc('\n', stdout); +} + +static struct option opts[] = { + { "tos", 1, 0, '1' }, + {0} +}; + +static void +parse_tos(const char *s, struct ipt_tos_info *info) +{ + unsigned int i; + unsigned int tos; + + if (string_to_number(s, 0, 255, &tos) != -1) { + if (tos == IPTOS_LOWDELAY + || tos == IPTOS_THROUGHPUT + || tos == IPTOS_RELIABILITY + || tos == IPTOS_MINCOST + || tos == IPTOS_NORMALSVC) { + info->tos = (u_int8_t )tos; + return; + } + } else { + for (i = 0; i<sizeof(TOS_values)/sizeof(struct TOS_value); i++) + if (strcasecmp(s,TOS_values[i].name) == 0) { + info->tos = TOS_values[i].TOS; + return; + } + } + exit_error(PARAMETER_PROBLEM, "Bad TOS value `%s'", s); +} + +/* Function which parses command options; returns true if it + ate an option */ +static int +parse(int c, char **argv, int invert, unsigned int *flags, + const struct ipt_entry *entry, + unsigned int *nfcache, + struct ipt_entry_match **match) +{ + struct ipt_tos_info *tosinfo = (struct ipt_tos_info *)(*match)->data; + + switch (c) { + case '1': + /* Ensure that `--tos' haven't been used yet. */ + if (*flags == 1) + exit_error(PARAMETER_PROBLEM, + "tos match: only use --tos once!"); + + check_inverse(optarg, &invert, &optind, 0); + parse_tos(argv[optind-1], tosinfo); + if (invert) + tosinfo->invert = 1; + *flags = 1; + break; + + default: + return 0; + } + return 1; +} + +static void +print_tos(u_int8_t tos, int numeric) +{ + unsigned int i; + + if (!numeric) { + for (i = 0; i<sizeof(TOS_values)/sizeof(struct TOS_value); i++) + if (TOS_values[i].TOS == tos) { + printf("%s ", TOS_values[i].name); + return; + } + } + printf("0x%02x ", tos); +} + +/* Final check; must have specified --tos. */ +static void +final_check(unsigned int flags) +{ + if (!flags) + exit_error(PARAMETER_PROBLEM, + "TOS match: You must specify `--tos'"); +} + +/* Prints out the matchinfo. */ +static void +print(const struct ipt_ip *ip, + const struct ipt_entry_match *match, + int numeric) +{ + const struct ipt_tos_info *info = (const struct ipt_tos_info *)match->data; + + printf("TOS match "); + if (info->invert) + printf("!"); + print_tos(info->tos, numeric); +} + +/* Saves the union ipt_matchinfo in parsable form to stdout. */ +static void +save(const struct ipt_ip *ip, const struct ipt_entry_match *match) +{ + const struct ipt_tos_info *info = (const struct ipt_tos_info *)match->data; + + if (info->invert) + printf("! "); + printf("--tos "); + print_tos(info->tos, 0); +} + +static struct iptables_match tos = { + .next = NULL, + .name = "tos", + .version = IPTABLES_VERSION, + .size = IPT_ALIGN(sizeof(struct ipt_tos_info)), + .userspacesize = IPT_ALIGN(sizeof(struct ipt_tos_info)), + .help = &help, + .parse = &parse, + .final_check = &final_check, + .print = &print, + .save = &save, + .extra_opts = opts +}; + +void ipt_2tos_init(void) +{ + register_match(&tos); +} |