1/*
2 * m_xt.c	xtables based targets
3 * 		utilities mostly ripped from iptables <duh, its the linux way>
4 *
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.
9 *
10 * Authors:  J Hadi Salim (hadi@cyberus.ca)
11 */
12
13/*XXX: in the future (xtables 1.4.3?) get rid of everything tagged
14 * as TC_CONFIG_XT_H */
15
16#include <syslog.h>
17#include <sys/socket.h>
18#include <netinet/in.h>
19#include <arpa/inet.h>
20#include <net/if.h>
21#include <linux/netfilter.h>
22#include <linux/netfilter_ipv4/ip_tables.h>
23#include <xtables.h>
24#include "utils.h"
25#include "tc_util.h"
26#include <linux/tc_act/tc_ipt.h>
27#include <stdio.h>
28#include <getopt.h>
29#include <errno.h>
30#include <string.h>
31#include <netdb.h>
32#include <stdlib.h>
33#include <ctype.h>
34#include <stdarg.h>
35#include <limits.h>
36#include <unistd.h>
37#include <fcntl.h>
38#include <sys/wait.h>
39#ifdef TC_CONFIG_XT_H
40#include "xt-internal.h"
41#endif
42
43#ifndef ALIGN
44#define ALIGN(x,a)		__ALIGN_MASK(x,(typeof(x))(a)-1)
45#define __ALIGN_MASK(x,mask)	(((x)+(mask))&~(mask))
46#endif
47
48static const char *pname = "tc-ipt";
49static const char *tname = "mangle";
50static const char *pversion = "0.2";
51
52static const char *ipthooks[] = {
53	"NF_IP_PRE_ROUTING",
54	"NF_IP_LOCAL_IN",
55	"NF_IP_FORWARD",
56	"NF_IP_LOCAL_OUT",
57	"NF_IP_POST_ROUTING",
58};
59
60static struct option original_opts[] = {
61	{"jump", 1, 0, 'j'},
62	{0, 0, 0, 0}
63};
64
65static struct option *opts = original_opts;
66static unsigned int global_option_offset = 0;
67char *lib_dir;
68const char *program_version = XTABLES_VERSION;
69const char *program_name = "tc-ipt";
70struct afinfo afinfo = {
71	.family         = AF_INET,
72	.libprefix      = "libxt_",
73	.ipproto        = IPPROTO_IP,
74	.kmod           = "ip_tables",
75	.so_rev_target  = IPT_SO_GET_REVISION_TARGET,
76};
77
78
79#define OPTION_OFFSET 256
80
81/*XXX: TC_CONFIG_XT_H */
82static void free_opts(struct option *local_opts)
83{
84	if (local_opts != original_opts) {
85		free(local_opts);
86		opts = original_opts;
87		global_option_offset = 0;
88	}
89}
90
91/*XXX: TC_CONFIG_XT_H */
92static struct option *
93merge_options(struct option *oldopts, const struct option *newopts,
94	      unsigned int *option_offset)
95{
96	struct option *merge;
97	unsigned int num_old, num_new, i;
98
99	for (num_old = 0; oldopts[num_old].name; num_old++) ;
100	for (num_new = 0; newopts[num_new].name; num_new++) ;
101
102	*option_offset = global_option_offset + OPTION_OFFSET;
103
104	merge = malloc(sizeof (struct option) * (num_new + num_old + 1));
105	memcpy(merge, oldopts, num_old * sizeof (struct option));
106	for (i = 0; i < num_new; i++) {
107		merge[num_old + i] = newopts[i];
108		merge[num_old + i].val += *option_offset;
109	}
110	memset(merge + num_old + num_new, 0, sizeof (struct option));
111
112	return merge;
113}
114
115
116/*XXX: TC_CONFIG_XT_H */
117#ifndef TRUE
118#define TRUE 1
119#endif
120#ifndef FALSE
121#define FALSE 0
122#endif
123
124/*XXX: TC_CONFIG_XT_H */
125int
126check_inverse(const char option[], int *invert, int *my_optind, int argc)
127{
128        if (option && strcmp(option, "!") == 0) {
129                if (*invert)
130                        exit_error(PARAMETER_PROBLEM,
131                                   "Multiple `!' flags not allowed");
132                *invert = TRUE;
133                if (my_optind != NULL) {
134                        ++*my_optind;
135                        if (argc && *my_optind > argc)
136                                exit_error(PARAMETER_PROBLEM,
137                                           "no argument following `!'");
138                }
139
140                return TRUE;
141        }
142        return FALSE;
143}
144
145/*XXX: TC_CONFIG_XT_H */
146void exit_error(enum exittype status, const char *msg, ...)
147{
148        va_list args;
149
150        va_start(args, msg);
151        fprintf(stderr, "%s v%s: ", pname, pversion);
152        vfprintf(stderr, msg, args);
153        va_end(args);
154        fprintf(stderr, "\n");
155        /* On error paths, make sure that we don't leak memory */
156        exit(status);
157}
158
159/*XXX: TC_CONFIG_XT_H */
160static void set_revision(char *name, u_int8_t revision)
161{
162	/* Old kernel sources don't have ".revision" field,
163	*  but we stole a byte from name. */
164	name[IPT_FUNCTION_MAXNAMELEN - 2] = '\0';
165	name[IPT_FUNCTION_MAXNAMELEN - 1] = revision;
166}
167
168/*
169 * we may need to check for version mismatch
170*/
171int
172build_st(struct xtables_target *target, struct xt_entry_target *t)
173{
174
175	size_t size =
176		    XT_ALIGN(sizeof (struct xt_entry_target)) + target->size;
177
178	if (NULL == t) {
179		target->t = fw_calloc(1, size);
180		target->t->u.target_size = size;
181		strcpy(target->t->u.user.name, target->name);
182		set_revision(target->t->u.user.name, target->revision);
183
184		if (target->init != NULL)
185			target->init(target->t);
186	} else {
187		target->t = t;
188	}
189	return 0;
190
191}
192
193inline void set_lib_dir(void)
194{
195
196	lib_dir = getenv("XTABLES_LIBDIR");
197	if (!lib_dir) {
198		lib_dir = getenv("IPTABLES_LIB_DIR");
199		if (lib_dir)
200			fprintf(stderr, "using deprecated IPTABLES_LIB_DIR \n");
201	}
202	if (lib_dir == NULL)
203		lib_dir = XT_LIB_DIR;
204
205}
206
207static int parse_ipt(struct action_util *a,int *argc_p,
208		     char ***argv_p, int tca_id, struct nlmsghdr *n)
209{
210	struct xtables_target *m = NULL;
211	struct ipt_entry fw;
212	struct rtattr *tail;
213	int c;
214	int rargc = *argc_p;
215	char **argv = *argv_p;
216	int argc = 0, iargc = 0;
217	char k[16];
218	int res = -1;
219	int size = 0;
220	int iok = 0, ok = 0;
221	__u32 hook = 0, index = 0;
222	res = 0;
223
224	set_lib_dir();
225
226	{
227		int i;
228		for (i = 0; i < rargc; i++) {
229			if (NULL == argv[i] || 0 == strcmp(argv[i], "action")) {
230				break;
231			}
232		}
233		iargc = argc = i;
234	}
235
236	if (argc <= 2) {
237		fprintf(stderr,"bad arguements to ipt %d vs %d \n", argc, rargc);
238		return -1;
239	}
240
241	while (1) {
242		c = getopt_long(argc, argv, "j:", opts, NULL);
243		if (c == -1)
244			break;
245		switch (c) {
246		case 'j':
247			m = find_target(optarg, TRY_LOAD);
248			if (NULL != m) {
249
250				if (0 > build_st(m, NULL)) {
251					printf(" %s error \n", m->name);
252					return -1;
253				}
254				opts =
255				    merge_options(opts, m->extra_opts,
256						  &m->option_offset);
257			} else {
258				fprintf(stderr," failed to find target %s\n\n", optarg);
259				return -1;
260			}
261			ok++;
262			break;
263
264		default:
265			memset(&fw, 0, sizeof (fw));
266			if (m) {
267				m->parse(c - m->option_offset, argv, 0,
268					 &m->tflags, NULL, &m->t);
269			} else {
270				fprintf(stderr," failed to find target %s\n\n", optarg);
271				return -1;
272
273			}
274			ok++;
275			break;
276
277		}
278	}
279
280	if (iargc > optind) {
281		if (matches(argv[optind], "index") == 0) {
282			if (get_u32(&index, argv[optind + 1], 10)) {
283				fprintf(stderr, "Illegal \"index\"\n");
284				free_opts(opts);
285				return -1;
286			}
287			iok++;
288
289			optind += 2;
290		}
291	}
292
293	if (!ok && !iok) {
294		fprintf(stderr," ipt Parser BAD!! (%s)\n", *argv);
295		return -1;
296	}
297
298	/* check that we passed the correct parameters to the target */
299	if (m)
300		m->final_check(m->tflags);
301
302	{
303		struct tcmsg *t = NLMSG_DATA(n);
304		if (t->tcm_parent != TC_H_ROOT
305		    && t->tcm_parent == TC_H_MAJ(TC_H_INGRESS)) {
306			hook = NF_IP_PRE_ROUTING;
307		} else {
308			hook = NF_IP_POST_ROUTING;
309		}
310	}
311
312	tail = NLMSG_TAIL(n);
313	addattr_l(n, MAX_MSG, tca_id, NULL, 0);
314	fprintf(stdout, "tablename: %s hook: %s\n ", tname, ipthooks[hook]);
315	fprintf(stdout, "\ttarget: ");
316
317	if (m)
318		m->print(NULL, m->t, 0);
319	fprintf(stdout, " index %d\n", index);
320
321	if (strlen(tname) > 16) {
322		size = 16;
323		k[15] = 0;
324	} else {
325		size = 1 + strlen(tname);
326	}
327	strncpy(k, tname, size);
328
329	addattr_l(n, MAX_MSG, TCA_IPT_TABLE, k, size);
330	addattr_l(n, MAX_MSG, TCA_IPT_HOOK, &hook, 4);
331	addattr_l(n, MAX_MSG, TCA_IPT_INDEX, &index, 4);
332	if (m)
333		addattr_l(n, MAX_MSG, TCA_IPT_TARG, m->t, m->t->u.target_size);
334	tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail;
335
336	argc -= optind;
337	argv += optind;
338	*argc_p = rargc - iargc;
339	*argv_p = argv;
340
341	optind = 0;
342	free_opts(opts);
343	/* Clear flags if target will be used again */
344        m->tflags=0;
345        m->used=0;
346	/* Free allocated memory */
347        if (m->t)
348            free(m->t);
349
350
351	return 0;
352
353}
354
355static int
356print_ipt(struct action_util *au,FILE * f, struct rtattr *arg)
357{
358	struct rtattr *tb[TCA_IPT_MAX + 1];
359	struct xt_entry_target *t = NULL;
360
361	if (arg == NULL)
362		return -1;
363
364	set_lib_dir();
365
366	parse_rtattr_nested(tb, TCA_IPT_MAX, arg);
367
368	if (tb[TCA_IPT_TABLE] == NULL) {
369		fprintf(f, "[NULL ipt table name ] assuming mangle ");
370	} else {
371		fprintf(f, "tablename: %s ",
372			(char *) RTA_DATA(tb[TCA_IPT_TABLE]));
373	}
374
375	if (tb[TCA_IPT_HOOK] == NULL) {
376		fprintf(f, "[NULL ipt hook name ]\n ");
377		return -1;
378	} else {
379		__u32 hook;
380		hook = *(__u32 *) RTA_DATA(tb[TCA_IPT_HOOK]);
381		fprintf(f, " hook: %s \n", ipthooks[hook]);
382	}
383
384	if (tb[TCA_IPT_TARG] == NULL) {
385		fprintf(f, "\t[NULL ipt target parameters ] \n");
386		return -1;
387	} else {
388		struct xtables_target *m = NULL;
389		t = RTA_DATA(tb[TCA_IPT_TARG]);
390		m = find_target(t->u.user.name, TRY_LOAD);
391		if (NULL != m) {
392			if (0 > build_st(m, t)) {
393				fprintf(stderr, " %s error \n", m->name);
394				return -1;
395			}
396
397			opts =
398			    merge_options(opts, m->extra_opts,
399					  &m->option_offset);
400		} else {
401			fprintf(stderr, " failed to find target %s\n\n",
402				t->u.user.name);
403			return -1;
404		}
405		fprintf(f, "\ttarget ");
406		m->print(NULL, m->t, 0);
407		if (tb[TCA_IPT_INDEX] == NULL) {
408			fprintf(f, " [NULL ipt target index ]\n");
409		} else {
410			__u32 index;
411			index = *(__u32 *) RTA_DATA(tb[TCA_IPT_INDEX]);
412			fprintf(f, " \n\tindex %d", index);
413		}
414
415		if (tb[TCA_IPT_CNT]) {
416			struct tc_cnt *c  = RTA_DATA(tb[TCA_IPT_CNT]);;
417			fprintf(f, " ref %d bind %d", c->refcnt, c->bindcnt);
418		}
419		if (show_stats) {
420			if (tb[TCA_IPT_TM]) {
421				struct tcf_t *tm = RTA_DATA(tb[TCA_IPT_TM]);
422				print_tm(f,tm);
423			}
424		}
425		fprintf(f, " \n");
426
427	}
428	free_opts(opts);
429
430	return 0;
431}
432
433struct action_util ipt_action_util = {
434        .id = "ipt",
435        .parse_aopt = parse_ipt,
436        .print_aopt = print_ipt,
437};
438
439