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/*
* m_xt.c xtables based targets
* utilities mostly ripped from iptables <duh, its the linux way>
*
* This program is free software; you can distribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
* Authors: J Hadi Salim (hadi@cyberus.ca)
*/
#include <syslog.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <net/if.h>
#include <limits.h>
#include <linux/netfilter.h>
#include <linux/netfilter_ipv4/ip_tables.h>
#include <xtables.h>
#include "utils.h"
#include "tc_util.h"
#include <linux/tc_act/tc_ipt.h>
#include <stdio.h>
#include <dlfcn.h>
#include <getopt.h>
#include <errno.h>
#include <string.h>
#include <netdb.h>
#include <stdlib.h>
#include <ctype.h>
#include <stdarg.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/wait.h>
#ifndef XT_LIB_DIR
# define XT_LIB_DIR "/lib/xtables"
#endif
#ifndef __ALIGN_KERNEL
#define __ALIGN_KERNEL(x, a) \
__ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1)
#define __ALIGN_KERNEL_MASK(x, mask) \
(((x) + (mask)) & ~(mask))
#endif
#ifndef ALIGN
#define ALIGN(x, a) __ALIGN_KERNEL((x), (a))
#endif
static const char *tname = "mangle";
char *lib_dir;
static const char * const ipthooks[] = {
"NF_IP_PRE_ROUTING",
"NF_IP_LOCAL_IN",
"NF_IP_FORWARD",
"NF_IP_LOCAL_OUT",
"NF_IP_POST_ROUTING",
};
static struct option original_opts[] = {
{
.name = "jump",
.has_arg = 1,
.val = 'j'
},
{0, 0, 0, 0}
};
static struct xtables_globals tcipt_globals = {
.option_offset = 0,
.program_name = "tc-ipt",
.program_version = "0.2",
.orig_opts = original_opts,
.opts = original_opts,
.exit_err = NULL,
#if XTABLES_VERSION_CODE >= 11
.compat_rev = xtables_compatible_revision,
#endif
};
/*
* we may need to check for version mismatch
*/
static int
build_st(struct xtables_target *target, struct xt_entry_target *t)
{
size_t size =
XT_ALIGN(sizeof(struct xt_entry_target)) + target->size;
if (t == NULL) {
target->t = xtables_calloc(1, size);
target->t->u.target_size = size;
strncpy(target->t->u.user.name, target->name,
sizeof(target->t->u.user.name) - 1);
target->t->u.user.revision = target->revision;
if (target->init != NULL)
target->init(target->t);
} else {
target->t = t;
}
return 0;
}
static void set_lib_dir(void)
{
lib_dir = getenv("XTABLES_LIBDIR");
if (!lib_dir) {
lib_dir = getenv("IPTABLES_LIB_DIR");
if (lib_dir)
fprintf(stderr, "using deprecated IPTABLES_LIB_DIR\n");
}
if (lib_dir == NULL)
lib_dir = XT_LIB_DIR;
}
static int get_xtables_target_opts(struct xtables_globals *globals,
struct xtables_target *m)
{
struct option *opts;
#if XTABLES_VERSION_CODE >= 6
opts = xtables_options_xfrm(globals->orig_opts,
globals->opts,
m->x6_options,
&m->option_offset);
#else
opts = xtables_merge_options(globals->opts,
m->extra_opts,
&m->option_offset);
#endif
if (!opts)
return -1;
globals->opts = opts;
return 0;
}
static int parse_ipt(struct action_util *a, int *argc_p,
char ***argv_p, int tca_id, struct nlmsghdr *n)
{
struct xtables_target *m = NULL;
#if XTABLES_VERSION_CODE >= 6
struct ipt_entry fw = {};
#endif
struct rtattr *tail;
int c;
char **argv = *argv_p;
int argc;
char k[16];
int size = 0;
int iok = 0, ok = 0;
__u32 hook = 0, index = 0;
/* copy tcipt_globals because .opts will be modified by iptables */
struct xtables_globals tmp_tcipt_globals = tcipt_globals;
xtables_init_all(&tmp_tcipt_globals, NFPROTO_IPV4);
set_lib_dir();
/* parse only up until the next action */
for (argc = 0; argc < *argc_p; argc++) {
if (!argv[argc] || !strcmp(argv[argc], "action"))
break;
}
if (argc <= 2) {
fprintf(stderr,
"too few arguments for xt, need at least '-j <target>'\n");
return -1;
}
while (1) {
c = getopt_long(argc, argv, "j:", tmp_tcipt_globals.opts, NULL);
if (c == -1)
break;
switch (c) {
case 'j':
m = xtables_find_target(optarg, XTF_TRY_LOAD);
if (!m) {
fprintf(stderr,
" failed to find target %s\n\n",
optarg);
return -1;
}
if (build_st(m, NULL) < 0) {
printf(" %s error\n", m->name);
return -1;
}
if (get_xtables_target_opts(&tmp_tcipt_globals,
m) < 0) {
fprintf(stderr,
" failed to find additional options for target %s\n\n",
optarg);
return -1;
}
ok++;
break;
default:
#if XTABLES_VERSION_CODE >= 6
if (m != NULL && m->x6_parse != NULL) {
xtables_option_tpcall(c, argv, 0, m, &fw);
#else
if (m != NULL && m->parse != NULL) {
m->parse(c - m->option_offset, argv, 0,
&m->tflags, NULL, &m->t);
#endif
} else {
fprintf(stderr,
"failed to find target %s\n\n", optarg);
return -1;
}
ok++;
break;
}
}
if (argc > optind) {
if (matches(argv[optind], "index") == 0) {
if (get_u32(&index, argv[optind + 1], 10)) {
fprintf(stderr, "Illegal \"index\"\n");
xtables_free_opts(1);
return -1;
}
iok++;
optind += 2;
}
}
if (!ok && !iok) {
fprintf(stderr, " ipt Parser BAD!! (%s)\n", *argv);
return -1;
}
/* check that we passed the correct parameters to the target */
#if XTABLES_VERSION_CODE >= 6
if (m)
xtables_option_tfcall(m);
#else
if (m && m->final_check)
m->final_check(m->tflags);
#endif
{
struct tcmsg *t = NLMSG_DATA(n);
if (t->tcm_parent != TC_H_ROOT
&& t->tcm_parent == TC_H_MAJ(TC_H_INGRESS)) {
hook = NF_IP_PRE_ROUTING;
} else {
hook = NF_IP_POST_ROUTING;
}
}
tail = NLMSG_TAIL(n);
addattr_l(n, MAX_MSG, tca_id, NULL, 0);
fprintf(stdout, "tablename: %s hook: %s\n ", tname, ipthooks[hook]);
fprintf(stdout, "\ttarget: ");
if (m) {
if (m->print)
m->print(NULL, m->t, 0);
else
printf("%s ", m->name);
}
fprintf(stdout, " index %d\n", index);
if (strlen(tname) >= 16) {
size = 15;
k[15] = 0;
} else {
size = 1 + strlen(tname);
}
strncpy(k, tname, size);
addattr_l(n, MAX_MSG, TCA_IPT_TABLE, k, size);
addattr_l(n, MAX_MSG, TCA_IPT_HOOK, &hook, 4);
addattr_l(n, MAX_MSG, TCA_IPT_INDEX, &index, 4);
if (m)
addattr_l(n, MAX_MSG, TCA_IPT_TARG, m->t, m->t->u.target_size);
tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail;
argv += optind;
*argc_p -= argc;
*argv_p = argv;
optind = 0;
xtables_free_opts(1);
if (m) {
/* Clear flags if target will be used again */
m->tflags = 0;
m->used = 0;
/* Free allocated memory */
if (m->t)
free(m->t);
}
return 0;
}
static int
print_ipt(struct action_util *au, FILE *f, struct rtattr *arg)
{
struct xtables_target *m;
struct rtattr *tb[TCA_IPT_MAX + 1];
struct xt_entry_target *t = NULL;
if (arg == NULL)
return -1;
/* copy tcipt_globals because .opts will be modified by iptables */
struct xtables_globals tmp_tcipt_globals = tcipt_globals;
xtables_init_all(&tmp_tcipt_globals, NFPROTO_IPV4);
set_lib_dir();
parse_rtattr_nested(tb, TCA_IPT_MAX, arg);
if (tb[TCA_IPT_TABLE] == NULL) {
fprintf(f, "[NULL ipt table name ] assuming mangle ");
} else {
fprintf(f, "tablename: %s ",
rta_getattr_str(tb[TCA_IPT_TABLE]));
}
if (tb[TCA_IPT_HOOK] == NULL) {
fprintf(f, "[NULL ipt hook name ]\n ");
return -1;
} else {
__u32 hook;
hook = rta_getattr_u32(tb[TCA_IPT_HOOK]);
fprintf(f, " hook: %s\n", ipthooks[hook]);
}
if (tb[TCA_IPT_TARG] == NULL) {
fprintf(f, "\t[NULL ipt target parameters ]\n");
return -1;
}
t = RTA_DATA(tb[TCA_IPT_TARG]);
m = xtables_find_target(t->u.user.name, XTF_TRY_LOAD);
if (!m) {
fprintf(stderr, " failed to find target %s\n\n",
t->u.user.name);
return -1;
}
if (build_st(m, t) < 0) {
fprintf(stderr, " %s error\n", m->name);
return -1;
}
if (get_xtables_target_opts(&tmp_tcipt_globals, m) < 0) {
fprintf(stderr,
" failed to find additional options for target %s\n\n",
t->u.user.name);
return -1;
}
fprintf(f, "\ttarget ");
m->print(NULL, m->t, 0);
if (tb[TCA_IPT_INDEX] == NULL) {
fprintf(f, " [NULL ipt target index ]\n");
} else {
__u32 index;
index = rta_getattr_u32(tb[TCA_IPT_INDEX]);
fprintf(f, "\n\tindex %u", index);
}
if (tb[TCA_IPT_CNT]) {
struct tc_cnt *c = RTA_DATA(tb[TCA_IPT_CNT]);
fprintf(f, " ref %d bind %d", c->refcnt, c->bindcnt);
}
if (show_stats) {
if (tb[TCA_IPT_TM]) {
struct tcf_t *tm = RTA_DATA(tb[TCA_IPT_TM]);
print_tm(f, tm);
}
}
fprintf(f, "\n");
xtables_free_opts(1);
return 0;
}
struct action_util xt_action_util = {
.id = "xt",
.parse_aopt = parse_ipt,
.print_aopt = print_ipt,
};