2 * m_ipt.c iptables based targets
3 * utilities mostly ripped from iptables <duh, its the linux way>
5 * This program is free software; you can distribute it and/or
6 * modify it under the terms of the GNU General Public License
7 * as published by the Free Software Foundation; either version
8 * 2 of the License, or (at your option) any later version.
10 * Authors: J Hadi Salim (hadi@cyberus.ca)
14 #include <sys/socket.h>
15 #include <netinet/in.h>
16 #include <arpa/inet.h>
19 #include <linux/netfilter.h>
20 #include <linux/netfilter_ipv4/ip_tables.h>
23 #include <linux/tc_act/tc_ipt.h>
38 static const char *pname = "tc-ipt";
39 static const char *tname = "mangle";
40 static const char *pversion = "0.1";
42 static const char *ipthooks[] = {
50 static struct option original_opts[] = {
55 static struct iptables_target *t_list = NULL;
56 static struct option *opts = original_opts;
57 static unsigned int global_option_offset = 0;
58 #define OPTION_OFFSET 256
63 register_target(struct iptables_target *me)
65 /* fprintf(stderr, "\nDummy register_target %s \n", me->name);
73 xtables_register_target(struct iptables_target *me)
80 exit_tryhelp(int status)
82 fprintf(stderr, "Try `%s -h' or '%s --help' for more information.\n",
88 exit_error(enum exittype status, char *msg, ...)
93 fprintf(stderr, "%s v%s: ", pname, pversion);
94 vfprintf(stderr, msg, args);
96 fprintf(stderr, "\n");
97 if (status == PARAMETER_PROBLEM)
99 if (status == VERSION_PROBLEM)
101 "Perhaps iptables or your kernel needs to be upgraded.\n");
105 /* stolen from iptables 1.2.11
106 They should really have them as a library so i can link to them
107 Email them next time i remember
111 addr_to_dotted(const struct in_addr *addrp)
114 const unsigned char *bytep;
116 bytep = (const unsigned char *) &(addrp->s_addr);
117 sprintf(buf, "%d.%d.%d.%d", bytep[0], bytep[1], bytep[2], bytep[3]);
121 int string_to_number_ll(const char *s, unsigned long long min,
122 unsigned long long max,
123 unsigned long long *ret)
125 unsigned long long number;
128 /* Handle hex, octal, etc. */
130 number = strtoull(s, &end, 0);
131 if (*end == '\0' && end != s) {
132 /* we parsed a number, let's see if we want this */
133 if (errno != ERANGE && min <= number && (!max || number <= max)) {
141 int string_to_number_l(const char *s, unsigned long min, unsigned long max,
145 unsigned long long number;
147 result = string_to_number_ll(s, min, max, &number);
148 *ret = (unsigned long)number;
153 int string_to_number(const char *s, unsigned int min, unsigned int max,
157 unsigned long number;
159 result = string_to_number_l(s, min, max, &number);
160 *ret = (unsigned int)number;
165 static void free_opts(struct option *opts)
167 if (opts != original_opts) {
169 opts = original_opts;
170 global_option_offset = 0;
174 static struct option *
175 merge_options(struct option *oldopts, const struct option *newopts,
176 unsigned int *option_offset)
178 struct option *merge;
179 unsigned int num_old, num_new, i;
181 for (num_old = 0; oldopts[num_old].name; num_old++) ;
182 for (num_new = 0; newopts[num_new].name; num_new++) ;
184 *option_offset = global_option_offset + OPTION_OFFSET;
186 merge = malloc(sizeof (struct option) * (num_new + num_old + 1));
187 memcpy(merge, oldopts, num_old * sizeof (struct option));
188 for (i = 0; i < num_new; i++) {
189 merge[num_old + i] = newopts[i];
190 merge[num_old + i].val += *option_offset;
192 memset(merge + num_old + num_new, 0, sizeof (struct option));
198 fw_calloc(size_t count, size_t size)
202 if ((p = (void *) calloc(count, size)) == NULL) {
203 perror("iptables: calloc failed");
209 static struct iptables_target *
212 struct iptables_target *m;
213 for (m = t_list; m; m = m->next) {
214 if (strcmp(m->name, name) == 0)
221 static struct iptables_target *
222 get_target_name(const char *name)
226 char *new_name, *lname;
227 struct iptables_target *m;
228 char path[strlen(lib_dir) + sizeof ("/libipt_.so") + strlen(name)];
230 new_name = malloc(strlen(name) + 1);
231 lname = malloc(strlen(name) + 1);
233 memset(new_name, '\0', strlen(name) + 1);
235 exit_error(PARAMETER_PROBLEM, "get_target_name");
238 memset(lname, '\0', strlen(name) + 1);
240 exit_error(PARAMETER_PROBLEM, "get_target_name");
242 strcpy(new_name, name);
245 if (isupper(lname[0])) {
247 for (i = 0; i < strlen(name); i++) {
248 lname[i] = tolower(lname[i]);
252 if (islower(new_name[0])) {
254 for (i = 0; i < strlen(new_name); i++) {
255 new_name[i] = toupper(new_name[i]);
259 /* try libxt_xx first */
260 sprintf(path, "%s/libxt_%s.so", lib_dir, new_name);
261 handle = dlopen(path, RTLD_LAZY);
263 /* try libipt_xx next */
264 sprintf(path, "%s/libipt_%s.so", lib_dir, new_name);
265 handle = dlopen(path, RTLD_LAZY);
268 sprintf(path, "%s/libxt_%s.so", lib_dir , lname);
269 handle = dlopen(path, RTLD_LAZY);
273 sprintf(path, "%s/libipt_%s.so", lib_dir , lname);
274 handle = dlopen(path, RTLD_LAZY);
276 /* ok, lets give up .. */
278 fputs(dlerror(), stderr);
285 m = dlsym(handle, new_name);
286 if ((error = dlerror()) != NULL) {
287 m = (struct iptables_target *) dlsym(handle, lname);
288 if ((error = dlerror()) != NULL) {
289 m = find_t(new_name);
293 fputs(error, stderr);
294 fprintf(stderr, "\n");
308 struct in_addr *dotted_to_addr(const char *dotted)
310 static struct in_addr addr;
311 unsigned char *addrp;
313 unsigned int onebyte;
317 /* copy dotted string, because we need to modify it */
318 strncpy(buf, dotted, sizeof (buf) - 1);
319 addrp = (unsigned char *) &(addr.s_addr);
322 for (i = 0; i < 3; i++) {
323 if ((q = strchr(p, '.')) == NULL)
324 return (struct in_addr *) NULL;
327 if (string_to_number(p, 0, 255, &onebyte) == -1)
328 return (struct in_addr *) NULL;
330 addrp[i] = (unsigned char) onebyte;
334 /* we've checked 3 bytes, now we check the last one */
335 if (string_to_number(p, 0, 255, &onebyte) == -1)
336 return (struct in_addr *) NULL;
338 addrp[3] = (unsigned char) onebyte;
343 static void set_revision(char *name, u_int8_t revision)
345 /* Old kernel sources don't have ".revision" field,
346 * but we stole a byte from name. */
347 name[IPT_FUNCTION_MAXNAMELEN - 2] = '\0';
348 name[IPT_FUNCTION_MAXNAMELEN - 1] = revision;
352 * we may need to check for version mismatch
355 build_st(struct iptables_target *target, struct ipt_entry_target *t)
357 unsigned int nfcache = 0;
363 IPT_ALIGN(sizeof (struct ipt_entry_target)) + target->size;
366 target->t = fw_calloc(1, size);
367 target->t->u.target_size = size;
369 if (target->init != NULL)
370 target->init(target->t, &nfcache);
371 set_revision(target->t->u.user.name, target->revision);
375 strcpy(target->t->u.user.name, target->name);
382 static int parse_ipt(struct action_util *a,int *argc_p,
383 char ***argv_p, int tca_id, struct nlmsghdr *n)
385 struct iptables_target *m = NULL;
390 char **argv = *argv_p;
391 int argc = 0, iargc = 0;
396 __u32 hook = 0, index = 0;
399 lib_dir = getenv("IPTABLES_LIB_DIR");
401 lib_dir = IPT_LIB_DIR;
405 for (i = 0; i < rargc; i++) {
406 if (NULL == argv[i] || 0 == strcmp(argv[i], "action")) {
414 fprintf(stderr,"bad arguements to ipt %d vs %d \n", argc, rargc);
419 c = getopt_long(argc, argv, "j:", opts, NULL);
424 m = get_target_name(optarg);
427 if (0 > build_st(m, NULL)) {
428 printf(" %s error \n", m->name);
432 merge_options(opts, m->extra_opts,
435 fprintf(stderr," failed to find target %s\n\n", optarg);
442 memset(&fw, 0, sizeof (fw));
444 m->parse(c - m->option_offset, argv, 0,
445 &m->tflags, NULL, &m->t);
447 fprintf(stderr," failed to find target %s\n\n", optarg);
457 if (iargc > optind) {
458 if (matches(argv[optind], "index") == 0) {
459 if (get_u32(&index, argv[optind + 1], 10)) {
460 fprintf(stderr, "Illegal \"index\"\n");
471 fprintf(stderr," ipt Parser BAD!! (%s)\n", *argv);
475 /* check that we passed the correct parameters to the target */
477 m->final_check(m->tflags);
480 struct tcmsg *t = NLMSG_DATA(n);
481 if (t->tcm_parent != TC_H_ROOT
482 && t->tcm_parent == TC_H_MAJ(TC_H_INGRESS)) {
483 hook = NF_IP_PRE_ROUTING;
485 hook = NF_IP_POST_ROUTING;
489 tail = NLMSG_TAIL(n);
490 addattr_l(n, MAX_MSG, tca_id, NULL, 0);
491 fprintf(stdout, "tablename: %s hook: %s\n ", tname, ipthooks[hook]);
492 fprintf(stdout, "\ttarget: ");
495 m->print(NULL, m->t, 0);
496 fprintf(stdout, " index %d\n", index);
498 if (strlen(tname) > 16) {
502 size = 1 + strlen(tname);
504 strncpy(k, tname, size);
506 addattr_l(n, MAX_MSG, TCA_IPT_TABLE, k, size);
507 addattr_l(n, MAX_MSG, TCA_IPT_HOOK, &hook, 4);
508 addattr_l(n, MAX_MSG, TCA_IPT_INDEX, &index, 4);
510 addattr_l(n, MAX_MSG, TCA_IPT_TARG, m->t, m->t->u.target_size);
511 tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail;
515 *argc_p = rargc - iargc;
520 /* Clear flags if target will be used again */
523 /* Free allocated memory */
533 print_ipt(struct action_util *au,FILE * f, struct rtattr *arg)
535 struct rtattr *tb[TCA_IPT_MAX + 1];
536 struct ipt_entry_target *t = NULL;
541 lib_dir = getenv("IPTABLES_LIB_DIR");
543 lib_dir = IPT_LIB_DIR;
545 parse_rtattr_nested(tb, TCA_IPT_MAX, arg);
547 if (tb[TCA_IPT_TABLE] == NULL) {
548 fprintf(f, "[NULL ipt table name ] assuming mangle ");
550 fprintf(f, "tablename: %s ",
551 (char *) RTA_DATA(tb[TCA_IPT_TABLE]));
554 if (tb[TCA_IPT_HOOK] == NULL) {
555 fprintf(f, "[NULL ipt hook name ]\n ");
559 hook = *(__u32 *) RTA_DATA(tb[TCA_IPT_HOOK]);
560 fprintf(f, " hook: %s \n", ipthooks[hook]);
563 if (tb[TCA_IPT_TARG] == NULL) {
564 fprintf(f, "\t[NULL ipt target parameters ] \n");
567 struct iptables_target *m = NULL;
568 t = RTA_DATA(tb[TCA_IPT_TARG]);
569 m = get_target_name(t->u.user.name);
571 if (0 > build_st(m, t)) {
572 fprintf(stderr, " %s error \n", m->name);
577 merge_options(opts, m->extra_opts,
580 fprintf(stderr, " failed to find target %s\n\n",
584 fprintf(f, "\ttarget ");
585 m->print(NULL, m->t, 0);
586 if (tb[TCA_IPT_INDEX] == NULL) {
587 fprintf(f, " [NULL ipt target index ]\n");
590 index = *(__u32 *) RTA_DATA(tb[TCA_IPT_INDEX]);
591 fprintf(f, " \n\tindex %d", index);
594 if (tb[TCA_IPT_CNT]) {
595 struct tc_cnt *c = RTA_DATA(tb[TCA_IPT_CNT]);;
596 fprintf(f, " ref %d bind %d", c->refcnt, c->bindcnt);
599 if (tb[TCA_IPT_TM]) {
600 struct tcf_t *tm = RTA_DATA(tb[TCA_IPT_TM]);
612 struct action_util ipt_action_util = {
614 .parse_aopt = parse_ipt,
615 .print_aopt = print_ipt,