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 exit_tryhelp(int status)
75 fprintf(stderr, "Try `%s -h' or '%s --help' for more information.\n",
81 exit_error(enum exittype status, char *msg, ...)
86 fprintf(stderr, "%s v%s: ", pname, pversion);
87 vfprintf(stderr, msg, args);
89 fprintf(stderr, "\n");
90 if (status == PARAMETER_PROBLEM)
92 if (status == VERSION_PROBLEM)
94 "Perhaps iptables or your kernel needs to be upgraded.\n");
98 /* stolen from iptables 1.2.11
99 They should really have them as a library so i can link to them
100 Email them next time i remember
104 addr_to_dotted(const struct in_addr *addrp)
107 const unsigned char *bytep;
109 bytep = (const unsigned char *) &(addrp->s_addr);
110 sprintf(buf, "%d.%d.%d.%d", bytep[0], bytep[1], bytep[2], bytep[3]);
114 int string_to_number_ll(const char *s, unsigned long long min,
115 unsigned long long max,
116 unsigned long long *ret)
118 unsigned long long number;
121 /* Handle hex, octal, etc. */
123 number = strtoull(s, &end, 0);
124 if (*end == '\0' && end != s) {
125 /* we parsed a number, let's see if we want this */
126 if (errno != ERANGE && min <= number && (!max || number <= max)) {
134 int string_to_number_l(const char *s, unsigned long min, unsigned long max,
138 unsigned long long number;
140 result = string_to_number_ll(s, min, max, &number);
141 *ret = (unsigned long)number;
146 int string_to_number(const char *s, unsigned int min, unsigned int max,
150 unsigned long number;
152 result = string_to_number_l(s, min, max, &number);
153 *ret = (unsigned int)number;
158 static void free_opts(struct option *opts)
160 if (opts != original_opts) {
162 opts = original_opts;
163 global_option_offset = 0;
167 static struct option *
168 merge_options(struct option *oldopts, const struct option *newopts,
169 unsigned int *option_offset)
171 struct option *merge;
172 unsigned int num_old, num_new, i;
174 for (num_old = 0; oldopts[num_old].name; num_old++) ;
175 for (num_new = 0; newopts[num_new].name; num_new++) ;
177 *option_offset = global_option_offset + OPTION_OFFSET;
179 merge = malloc(sizeof (struct option) * (num_new + num_old + 1));
180 memcpy(merge, oldopts, num_old * sizeof (struct option));
181 for (i = 0; i < num_new; i++) {
182 merge[num_old + i] = newopts[i];
183 merge[num_old + i].val += *option_offset;
185 memset(merge + num_old + num_new, 0, sizeof (struct option));
191 fw_calloc(size_t count, size_t size)
195 if ((p = (void *) calloc(count, size)) == NULL) {
196 perror("iptables: calloc failed");
202 static struct iptables_target *
205 struct iptables_target *m;
206 for (m = t_list; m; m = m->next) {
207 if (strcmp(m->name, name) == 0)
214 static struct iptables_target *
215 get_target_name(const char *name)
219 char *new_name, *lname;
220 struct iptables_target *m;
221 char path[strlen(lib_dir) + sizeof ("/libipt_.so") + strlen(name)];
223 new_name = malloc(strlen(name) + 1);
224 lname = malloc(strlen(name) + 1);
226 memset(new_name, '\0', strlen(name) + 1);
228 exit_error(PARAMETER_PROBLEM, "get_target_name");
231 memset(lname, '\0', strlen(name) + 1);
233 exit_error(PARAMETER_PROBLEM, "get_target_name");
235 strcpy(new_name, name);
238 if (isupper(lname[0])) {
240 for (i = 0; i < strlen(name); i++) {
241 lname[i] = tolower(lname[i]);
245 if (islower(new_name[0])) {
247 for (i = 0; i < strlen(new_name); i++) {
248 new_name[i] = toupper(new_name[i]);
252 sprintf(path, "%s/libipt_%s.so",lib_dir, new_name);
253 handle = dlopen(path, RTLD_LAZY);
255 sprintf(path, lib_dir, "/libipt_%s.so", lname);
256 handle = dlopen(path, RTLD_LAZY);
258 fputs(dlerror(), stderr);
264 m = dlsym(handle, new_name);
265 if ((error = dlerror()) != NULL) {
266 m = (struct iptables_target *) dlsym(handle, lname);
267 if ((error = dlerror()) != NULL) {
268 m = find_t(new_name);
272 fputs(error, stderr);
273 fprintf(stderr, "\n");
285 struct in_addr *dotted_to_addr(const char *dotted)
287 static struct in_addr addr;
288 unsigned char *addrp;
290 unsigned int onebyte;
294 /* copy dotted string, because we need to modify it */
295 strncpy(buf, dotted, sizeof (buf) - 1);
296 addrp = (unsigned char *) &(addr.s_addr);
299 for (i = 0; i < 3; i++) {
300 if ((q = strchr(p, '.')) == NULL)
301 return (struct in_addr *) NULL;
304 if (string_to_number(p, 0, 255, &onebyte) == -1)
305 return (struct in_addr *) NULL;
307 addrp[i] = (unsigned char) onebyte;
311 /* we've checked 3 bytes, now we check the last one */
312 if (string_to_number(p, 0, 255, &onebyte) == -1)
313 return (struct in_addr *) NULL;
315 addrp[3] = (unsigned char) onebyte;
320 static void set_revision(char *name, u_int8_t revision)
322 /* Old kernel sources don't have ".revision" field,
323 * but we stole a byte from name. */
324 name[IPT_FUNCTION_MAXNAMELEN - 2] = '\0';
325 name[IPT_FUNCTION_MAXNAMELEN - 1] = revision;
329 * we may need to check for version mismatch
332 build_st(struct iptables_target *target, struct ipt_entry_target *t)
334 unsigned int nfcache = 0;
340 IPT_ALIGN(sizeof (struct ipt_entry_target)) + target->size;
343 target->t = fw_calloc(1, size);
344 target->t->u.target_size = size;
346 if (target->init != NULL)
347 target->init(target->t, &nfcache);
348 set_revision(target->t->u.user.name, target->revision);
352 strcpy(target->t->u.user.name, target->name);
359 static int parse_ipt(struct action_util *a,int *argc_p,
360 char ***argv_p, int tca_id, struct nlmsghdr *n)
362 struct iptables_target *m = NULL;
367 char **argv = *argv_p;
368 int argc = 0, iargc = 0;
373 __u32 hook = 0, index = 0;
376 lib_dir = getenv("IPTABLES_LIB_DIR");
378 lib_dir = IPT_LIB_DIR;
382 for (i = 0; i < rargc; i++) {
383 if (NULL == argv[i] || 0 == strcmp(argv[i], "action")) {
391 fprintf(stderr,"bad arguements to ipt %d vs %d \n", argc, rargc);
396 c = getopt_long(argc, argv, "j:", opts, NULL);
401 m = get_target_name(optarg);
404 if (0 > build_st(m, NULL)) {
405 printf(" %s error \n", m->name);
409 merge_options(opts, m->extra_opts,
412 fprintf(stderr," failed to find target %s\n\n", optarg);
419 memset(&fw, 0, sizeof (fw));
421 m->parse(c - m->option_offset, argv, 0,
422 &m->tflags, NULL, &m->t);
424 fprintf(stderr," failed to find target %s\n\n", optarg);
434 if (iargc > optind) {
435 if (matches(argv[optind], "index") == 0) {
436 if (get_u32(&index, argv[optind + 1], 10)) {
437 fprintf(stderr, "Illegal \"index\"\n");
448 fprintf(stderr," ipt Parser BAD!! (%s)\n", *argv);
452 /* check that we passed the correct parameters to the target */
454 m->final_check(m->tflags);
457 struct tcmsg *t = NLMSG_DATA(n);
458 if (t->tcm_parent != TC_H_ROOT
459 && t->tcm_parent == TC_H_MAJ(TC_H_INGRESS)) {
460 hook = NF_IP_PRE_ROUTING;
462 hook = NF_IP_POST_ROUTING;
466 tail = NLMSG_TAIL(n);
467 addattr_l(n, MAX_MSG, tca_id, NULL, 0);
468 fprintf(stdout, "tablename: %s hook: %s\n ", tname, ipthooks[hook]);
469 fprintf(stdout, "\ttarget: ");
472 m->print(NULL, m->t, 0);
473 fprintf(stdout, " index %d\n", index);
475 if (strlen(tname) > 16) {
479 size = 1 + strlen(tname);
481 strncpy(k, tname, size);
483 addattr_l(n, MAX_MSG, TCA_IPT_TABLE, k, size);
484 addattr_l(n, MAX_MSG, TCA_IPT_HOOK, &hook, 4);
485 addattr_l(n, MAX_MSG, TCA_IPT_INDEX, &index, 4);
487 addattr_l(n, MAX_MSG, TCA_IPT_TARG, m->t, m->t->u.target_size);
488 tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail;
492 *argc_p = rargc - iargc;
503 print_ipt(struct action_util *au,FILE * f, struct rtattr *arg)
505 struct rtattr *tb[TCA_IPT_MAX + 1];
506 struct ipt_entry_target *t = NULL;
511 lib_dir = getenv("IPTABLES_LIB_DIR");
513 lib_dir = IPT_LIB_DIR;
515 parse_rtattr_nested(tb, TCA_IPT_MAX, arg);
517 if (tb[TCA_IPT_TABLE] == NULL) {
518 fprintf(f, "[NULL ipt table name ] assuming mangle ");
520 fprintf(f, "tablename: %s ",
521 (char *) RTA_DATA(tb[TCA_IPT_TABLE]));
524 if (tb[TCA_IPT_HOOK] == NULL) {
525 fprintf(f, "[NULL ipt hook name ]\n ");
529 hook = *(__u32 *) RTA_DATA(tb[TCA_IPT_HOOK]);
530 fprintf(f, " hook: %s \n", ipthooks[hook]);
533 if (tb[TCA_IPT_TARG] == NULL) {
534 fprintf(f, "\t[NULL ipt target parameters ] \n");
537 struct iptables_target *m = NULL;
538 t = RTA_DATA(tb[TCA_IPT_TARG]);
539 m = get_target_name(t->u.user.name);
541 if (0 > build_st(m, t)) {
542 fprintf(stderr, " %s error \n", m->name);
547 merge_options(opts, m->extra_opts,
550 fprintf(stderr, " failed to find target %s\n\n",
554 fprintf(f, "\ttarget ");
555 m->print(NULL, m->t, 0);
556 if (tb[TCA_IPT_INDEX] == NULL) {
557 fprintf(f, " [NULL ipt target index ]\n");
560 index = *(__u32 *) RTA_DATA(tb[TCA_IPT_INDEX]);
561 fprintf(f, " \n\tindex %d", index);
564 if (tb[TCA_IPT_CNT]) {
565 struct tc_cnt *c = RTA_DATA(tb[TCA_IPT_CNT]);;
566 fprintf(f, " ref %d bind %d", c->refcnt, c->bindcnt);
569 if (tb[TCA_IPT_TM]) {
570 struct tcf_t *tm = RTA_DATA(tb[TCA_IPT_TM]);
582 struct action_util ipt_action_util = {
584 .parse_aopt = parse_ipt,
585 .print_aopt = print_ipt,