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_ipv4/ip_tables.h>
22 #include <linux/tc_act/tc_ipt.h>
37 static const char *pname = "tc-ipt";
38 static const char *tname = "mangle";
39 static const char *pversion = "0.1";
41 static const char *ipthooks[] = {
49 static struct option original_opts[] = {
54 static struct iptables_target *t_list = NULL;
55 static struct option *opts = original_opts;
56 static unsigned int global_option_offset = 0;
57 #define OPTION_OFFSET 256
62 register_target(struct iptables_target *me)
64 /* fprintf(stderr, "\nDummy register_target %s \n", me->name);
72 exit_tryhelp(int status)
74 fprintf(stderr, "Try `%s -h' or '%s --help' for more information.\n",
80 exit_error(enum exittype status, char *msg, ...)
85 fprintf(stderr, "%s v%s: ", pname, pversion);
86 vfprintf(stderr, msg, args);
88 fprintf(stderr, "\n");
89 if (status == PARAMETER_PROBLEM)
91 if (status == VERSION_PROBLEM)
93 "Perhaps iptables or your kernel needs to be upgraded.\n");
97 /* stolen from iptables 1.2.11
98 They should really have them as a library so i can link to them
99 Email them next time i remember
103 addr_to_dotted(const struct in_addr *addrp)
106 const unsigned char *bytep;
108 bytep = (const unsigned char *) &(addrp->s_addr);
109 sprintf(buf, "%d.%d.%d.%d", bytep[0], bytep[1], bytep[2], bytep[3]);
113 int string_to_number_ll(const char *s, unsigned long long min,
114 unsigned long long max,
115 unsigned long long *ret)
117 unsigned long long number;
120 /* Handle hex, octal, etc. */
122 number = strtoull(s, &end, 0);
123 if (*end == '\0' && end != s) {
124 /* we parsed a number, let's see if we want this */
125 if (errno != ERANGE && min <= number && (!max || number <= max)) {
133 int string_to_number_l(const char *s, unsigned long min, unsigned long max,
137 unsigned long long number;
139 result = string_to_number_ll(s, min, max, &number);
140 *ret = (unsigned long)number;
145 int string_to_number(const char *s, unsigned int min, unsigned int max,
149 unsigned long number;
151 result = string_to_number_l(s, min, max, &number);
152 *ret = (unsigned int)number;
157 static void free_opts(struct option *opts)
159 if (opts != original_opts) {
161 opts = original_opts;
162 global_option_offset = 0;
166 static struct option *
167 merge_options(struct option *oldopts, const struct option *newopts,
168 unsigned int *option_offset)
170 struct option *merge;
171 unsigned int num_old, num_new, i;
173 for (num_old = 0; oldopts[num_old].name; num_old++) ;
174 for (num_new = 0; newopts[num_new].name; num_new++) ;
176 *option_offset = global_option_offset + OPTION_OFFSET;
178 merge = malloc(sizeof (struct option) * (num_new + num_old + 1));
179 memcpy(merge, oldopts, num_old * sizeof (struct option));
180 for (i = 0; i < num_new; i++) {
181 merge[num_old + i] = newopts[i];
182 merge[num_old + i].val += *option_offset;
184 memset(merge + num_old + num_new, 0, sizeof (struct option));
190 fw_calloc(size_t count, size_t size)
194 if ((p = (void *) calloc(count, size)) == NULL) {
195 perror("iptables: calloc failed");
201 static struct iptables_target *
204 struct iptables_target *m;
205 for (m = t_list; m; m = m->next) {
206 if (strcmp(m->name, name) == 0)
213 static struct iptables_target *
214 get_target_name(const char *name)
218 char *new_name, *lname;
219 struct iptables_target *m;
220 char path[strlen(lib_dir) + sizeof ("/libipt_.so") + strlen(name)];
222 new_name = malloc(strlen(name) + 1);
223 lname = malloc(strlen(name) + 1);
225 memset(new_name, '\0', strlen(name) + 1);
227 exit_error(PARAMETER_PROBLEM, "get_target_name");
230 memset(lname, '\0', strlen(name) + 1);
232 exit_error(PARAMETER_PROBLEM, "get_target_name");
234 strcpy(new_name, name);
237 if (isupper(lname[0])) {
239 for (i = 0; i < strlen(name); i++) {
240 lname[i] = tolower(lname[i]);
244 if (islower(new_name[0])) {
246 for (i = 0; i < strlen(new_name); i++) {
247 new_name[i] = toupper(new_name[i]);
251 sprintf(path, "%s/libipt_%s.so",lib_dir, new_name);
252 handle = dlopen(path, RTLD_LAZY);
254 sprintf(path, lib_dir, "/libipt_%s.so", lname);
255 handle = dlopen(path, RTLD_LAZY);
257 fputs(dlerror(), stderr);
263 m = dlsym(handle, new_name);
264 if ((error = dlerror()) != NULL) {
265 m = (struct iptables_target *) dlsym(handle, lname);
266 if ((error = dlerror()) != NULL) {
267 m = find_t(new_name);
271 fputs(error, stderr);
272 fprintf(stderr, "\n");
284 struct in_addr *dotted_to_addr(const char *dotted)
286 static struct in_addr addr;
287 unsigned char *addrp;
289 unsigned int onebyte;
293 /* copy dotted string, because we need to modify it */
294 strncpy(buf, dotted, sizeof (buf) - 1);
295 addrp = (unsigned char *) &(addr.s_addr);
298 for (i = 0; i < 3; i++) {
299 if ((q = strchr(p, '.')) == NULL)
300 return (struct in_addr *) NULL;
303 if (string_to_number(p, 0, 255, &onebyte) == -1)
304 return (struct in_addr *) NULL;
306 addrp[i] = (unsigned char) onebyte;
310 /* we've checked 3 bytes, now we check the last one */
311 if (string_to_number(p, 0, 255, &onebyte) == -1)
312 return (struct in_addr *) NULL;
314 addrp[3] = (unsigned char) onebyte;
319 static void set_revision(char *name, u_int8_t revision)
321 /* Old kernel sources don't have ".revision" field,
322 * but we stole a byte from name. */
323 name[IPT_FUNCTION_MAXNAMELEN - 2] = '\0';
324 name[IPT_FUNCTION_MAXNAMELEN - 1] = revision;
328 * we may need to check for version mismatch
331 build_st(struct iptables_target *target, struct ipt_entry_target *t)
333 unsigned int nfcache = 0;
339 IPT_ALIGN(sizeof (struct ipt_entry_target)) + target->size;
342 target->t = fw_calloc(1, size);
343 target->t->u.target_size = size;
345 if (target->init != NULL)
346 target->init(target->t, &nfcache);
347 set_revision(target->t->u.user.name, target->revision);
351 strcpy(target->t->u.user.name, target->name);
358 static int parse_ipt(struct action_util *a,int *argc_p,
359 char ***argv_p, int tca_id, struct nlmsghdr *n)
361 struct iptables_target *m = NULL;
366 char **argv = *argv_p;
367 int argc = 0, iargc = 0;
372 __u32 hook = 0, index = 0;
375 lib_dir = getenv("IPTABLES_LIB_DIR");
377 lib_dir = IPT_LIB_DIR;
381 for (i = 0; i < rargc; i++) {
382 if (NULL == argv[i] || 0 == strcmp(argv[i], "action")) {
390 fprintf(stderr,"bad arguements to ipt %d vs %d \n", argc, rargc);
395 c = getopt_long(argc, argv, "j:", opts, NULL);
400 m = get_target_name(optarg);
403 if (0 > build_st(m, NULL)) {
404 printf(" %s error \n", m->name);
408 merge_options(opts, m->extra_opts,
411 fprintf(stderr," failed to find target %s\n\n", optarg);
418 memset(&fw, 0, sizeof (fw));
420 m->parse(c - m->option_offset, argv, 0,
421 &m->tflags, NULL, &m->t);
423 fprintf(stderr," failed to find target %s\n\n", optarg);
433 if (iargc > optind) {
434 if (matches(argv[optind], "index") == 0) {
435 if (get_u32(&index, argv[optind + 1], 10)) {
436 fprintf(stderr, "Illegal \"index\"\n");
447 fprintf(stderr," ipt Parser BAD!! (%s)\n", *argv);
451 /* check that we passed the correct parameters to the target */
453 m->final_check(m->tflags);
456 struct tcmsg *t = NLMSG_DATA(n);
457 if (t->tcm_parent != TC_H_ROOT
458 && t->tcm_parent == TC_H_MAJ(TC_H_INGRESS)) {
459 hook = NF_IP_PRE_ROUTING;
461 hook = NF_IP_POST_ROUTING;
465 tail = NLMSG_TAIL(n);
466 addattr_l(n, MAX_MSG, tca_id, NULL, 0);
467 fprintf(stdout, "tablename: %s hook: %s\n ", tname, ipthooks[hook]);
468 fprintf(stdout, "\ttarget: ");
471 m->print(NULL, m->t, 0);
472 fprintf(stdout, " index %d\n", index);
474 if (strlen(tname) > 16) {
478 size = 1 + strlen(tname);
480 strncpy(k, tname, size);
482 addattr_l(n, MAX_MSG, TCA_IPT_TABLE, k, size);
483 addattr_l(n, MAX_MSG, TCA_IPT_HOOK, &hook, 4);
484 addattr_l(n, MAX_MSG, TCA_IPT_INDEX, &index, 4);
486 addattr_l(n, MAX_MSG, TCA_IPT_TARG, m->t, m->t->u.target_size);
487 tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail;
491 *argc_p = rargc - iargc;
502 print_ipt(struct action_util *au,FILE * f, struct rtattr *arg)
504 struct rtattr *tb[TCA_IPT_MAX + 1];
505 struct ipt_entry_target *t = NULL;
510 lib_dir = getenv("IPTABLES_LIB_DIR");
512 lib_dir = IPT_LIB_DIR;
514 parse_rtattr_nested(tb, TCA_IPT_MAX, arg);
516 if (tb[TCA_IPT_TABLE] == NULL) {
517 fprintf(f, "[NULL ipt table name ] assuming mangle ");
519 fprintf(f, "tablename: %s ",
520 (char *) RTA_DATA(tb[TCA_IPT_TABLE]));
523 if (tb[TCA_IPT_HOOK] == NULL) {
524 fprintf(f, "[NULL ipt hook name ]\n ");
528 hook = *(__u32 *) RTA_DATA(tb[TCA_IPT_HOOK]);
529 fprintf(f, " hook: %s \n", ipthooks[hook]);
532 if (tb[TCA_IPT_TARG] == NULL) {
533 fprintf(f, "\t[NULL ipt target parameters ] \n");
536 struct iptables_target *m = NULL;
537 t = RTA_DATA(tb[TCA_IPT_TARG]);
538 m = get_target_name(t->u.user.name);
540 if (0 > build_st(m, t)) {
541 fprintf(stderr, " %s error \n", m->name);
546 merge_options(opts, m->extra_opts,
549 fprintf(stderr, " failed to find target %s\n\n",
553 fprintf(f, "\ttarget ");
554 m->print(NULL, m->t, 0);
555 if (tb[TCA_IPT_INDEX] == NULL) {
556 fprintf(f, " [NULL ipt target index ]\n");
559 index = *(__u32 *) RTA_DATA(tb[TCA_IPT_INDEX]);
560 fprintf(f, " \n\tindex %d", index);
563 if (tb[TCA_IPT_CNT]) {
564 struct tc_cnt *c = RTA_DATA(tb[TCA_IPT_CNT]);;
565 fprintf(f, " ref %d bind %d", c->refcnt, c->bindcnt);
568 if (tb[TCA_IPT_TM]) {
569 struct tcf_t *tm = RTA_DATA(tb[TCA_IPT_TM]);
581 struct action_util ipt_action_util = {
583 .parse_aopt = parse_ipt,
584 .print_aopt = print_ipt,