xtables.c revision 7a236f4cc685a420c1a782a5db614a93baf37ccf
1/*
2 * (C) 2000-2006 by the netfilter coreteam <coreteam@netfilter.org>:
3 *
4 *	This program is free software; you can redistribute it and/or modify
5 *	it under the terms of the GNU General Public License as published by
6 *	the Free Software Foundation; either version 2 of the License, or
7 *	(at your option) any later version.
8 *
9 *	This program is distributed in the hope that it will be useful,
10 *	but WITHOUT ANY WARRANTY; without even the implied warranty of
11 *	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12 *	GNU General Public License for more details.
13 *
14 *	You should have received a copy of the GNU General Public License
15 *	along with this program; if not, write to the Free Software
16 *	Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
17 */
18
19#include <errno.h>
20#include <fcntl.h>
21#include <netdb.h>
22#include <stdarg.h>
23#include <stdbool.h>
24#include <stdio.h>
25#include <stdlib.h>
26#include <string.h>
27#include <unistd.h>
28#include <sys/socket.h>
29#include <sys/stat.h>
30#include <sys/types.h>
31#include <sys/wait.h>
32#include <arpa/inet.h>
33
34#include <xtables.h>
35
36#ifndef NO_SHARED_LIBS
37#include <dlfcn.h>
38#endif
39
40#define NPROTO	255
41
42#ifndef PROC_SYS_MODPROBE
43#define PROC_SYS_MODPROBE "/proc/sys/kernel/modprobe"
44#endif
45
46char *lib_dir;
47
48/* the path to command to load kernel module */
49const char *modprobe = NULL;
50
51/* Keeping track of external matches and targets: linked lists.  */
52struct xtables_match *xtables_matches;
53struct xtables_target *xtables_targets;
54
55void *fw_calloc(size_t count, size_t size)
56{
57	void *p;
58
59	if ((p = calloc(count, size)) == NULL) {
60		perror("ip[6]tables: calloc failed");
61		exit(1);
62	}
63
64	return p;
65}
66
67void *fw_malloc(size_t size)
68{
69	void *p;
70
71	if ((p = malloc(size)) == NULL) {
72		perror("ip[6]tables: malloc failed");
73		exit(1);
74	}
75
76	return p;
77}
78
79static char *get_modprobe(void)
80{
81	int procfile;
82	char *ret;
83
84#define PROCFILE_BUFSIZ	1024
85	procfile = open(PROC_SYS_MODPROBE, O_RDONLY);
86	if (procfile < 0)
87		return NULL;
88
89	ret = (char *) malloc(PROCFILE_BUFSIZ);
90	if (ret) {
91		memset(ret, 0, PROCFILE_BUFSIZ);
92		switch (read(procfile, ret, PROCFILE_BUFSIZ)) {
93		case -1: goto fail;
94		case PROCFILE_BUFSIZ: goto fail; /* Partial read.  Wierd */
95		}
96		if (ret[strlen(ret)-1]=='\n')
97			ret[strlen(ret)-1]=0;
98		close(procfile);
99		return ret;
100	}
101 fail:
102	free(ret);
103	close(procfile);
104	return NULL;
105}
106
107int xtables_insmod(const char *modname, const char *modprobe, int quiet)
108{
109	char *buf = NULL;
110	char *argv[4];
111	int status;
112
113	/* If they don't explicitly set it, read out of kernel */
114	if (!modprobe) {
115		buf = get_modprobe();
116		if (!buf)
117			return -1;
118		modprobe = buf;
119	}
120
121	switch (fork()) {
122	case 0:
123		argv[0] = (char *)modprobe;
124		argv[1] = (char *)modname;
125		if (quiet) {
126			argv[2] = "-q";
127			argv[3] = NULL;
128		} else {
129			argv[2] = NULL;
130			argv[3] = NULL;
131		}
132		execv(argv[0], argv);
133
134		/* not usually reached */
135		exit(1);
136	case -1:
137		return -1;
138
139	default: /* parent */
140		wait(&status);
141	}
142
143	free(buf);
144	if (WIFEXITED(status) && WEXITSTATUS(status) == 0)
145		return 0;
146	return -1;
147}
148
149int load_xtables_ko(const char *modprobe, int quiet)
150{
151	static int loaded = 0;
152	static int ret = -1;
153
154	if (!loaded) {
155		ret = xtables_insmod(afinfo.kmod, modprobe, quiet);
156		loaded = (ret == 0);
157	}
158
159	return ret;
160}
161
162int string_to_number_ll(const char *s, unsigned long long min,
163			unsigned long long max, unsigned long long *ret)
164{
165	unsigned long long number;
166	char *end;
167
168	/* Handle hex, octal, etc. */
169	errno = 0;
170	number = strtoull(s, &end, 0);
171	if (*end == '\0' && end != s) {
172		/* we parsed a number, let's see if we want this */
173		if (errno != ERANGE && min <= number && (!max || number <= max)) {
174			*ret = number;
175			return 0;
176		}
177	}
178	return -1;
179}
180
181int string_to_number_l(const char *s, unsigned long min, unsigned long max,
182		       unsigned long *ret)
183{
184	int result;
185	unsigned long long number;
186
187	result = string_to_number_ll(s, min, max, &number);
188	*ret = (unsigned long)number;
189
190	return result;
191}
192
193int string_to_number(const char *s, unsigned int min, unsigned int max,
194		unsigned int *ret)
195{
196	int result;
197	unsigned long number;
198
199	result = string_to_number_l(s, min, max, &number);
200	*ret = (unsigned int)number;
201
202	return result;
203}
204
205/*
206 * strtonum{,l} - string to number conversion
207 *
208 * If @end is NULL, we assume the caller does not want
209 * a case like "15a", so reject it.
210 */
211bool strtonuml(const char *s, char **end, unsigned long *value,
212               unsigned long min, unsigned long max)
213{
214	unsigned long v;
215	char *my_end;
216
217	errno = 0;
218	v = strtoul(s, &my_end, 0);
219
220	if (my_end == s)
221		return false;
222	if (end != NULL)
223		*end = my_end;
224
225	if (errno != ERANGE && min <= v && (max == 0 || v <= max)) {
226		if (value != NULL)
227			*value = v;
228		if (end == NULL)
229			return *my_end == '\0';
230		return true;
231	}
232
233	return false;
234}
235
236bool strtonum(const char *s, char **end, unsigned int *value,
237                  unsigned int min, unsigned int max)
238{
239	unsigned long v;
240	bool ret;
241
242	ret = strtonuml(s, end, &v, min, max);
243	if (value != NULL)
244		*value = v;
245	return ret;
246}
247
248int service_to_port(const char *name, const char *proto)
249{
250	struct servent *service;
251
252	if ((service = getservbyname(name, proto)) != NULL)
253		return ntohs((unsigned short) service->s_port);
254
255	return -1;
256}
257
258u_int16_t parse_port(const char *port, const char *proto)
259{
260	unsigned int portnum;
261
262	if ((string_to_number(port, 0, 65535, &portnum)) != -1 ||
263	    (portnum = service_to_port(port, proto)) != (unsigned)-1)
264		return (u_int16_t)portnum;
265
266	exit_error(PARAMETER_PROBLEM,
267		   "invalid port/service `%s' specified", port);
268}
269
270void parse_interface(const char *arg, char *vianame, unsigned char *mask)
271{
272	int vialen = strlen(arg);
273	unsigned int i;
274
275	memset(mask, 0, IFNAMSIZ);
276	memset(vianame, 0, IFNAMSIZ);
277
278	if (vialen + 1 > IFNAMSIZ)
279		exit_error(PARAMETER_PROBLEM,
280			   "interface name `%s' must be shorter than IFNAMSIZ"
281			   " (%i)", arg, IFNAMSIZ-1);
282
283	strcpy(vianame, arg);
284	if ((vialen == 0) || (vialen == 1 && vianame[0] == '+'))
285		memset(mask, 0, IFNAMSIZ);
286	else if (vianame[vialen - 1] == '+') {
287		memset(mask, 0xFF, vialen - 1);
288		memset(mask + vialen - 1, 0, IFNAMSIZ - vialen + 1);
289		/* Don't remove `+' here! -HW */
290	} else {
291		/* Include nul-terminator in match */
292		memset(mask, 0xFF, vialen + 1);
293		memset(mask + vialen + 1, 0, IFNAMSIZ - vialen - 1);
294		for (i = 0; vianame[i]; i++) {
295			if (vianame[i] == ':' ||
296			    vianame[i] == '!' ||
297			    vianame[i] == '*') {
298				fprintf(stderr,
299					"Warning: weird character in interface"
300					" `%s' (No aliases, :, ! or *).\n",
301					vianame);
302				break;
303			}
304		}
305	}
306}
307
308struct xtables_match *find_match(const char *name, enum xt_tryload tryload,
309				 struct xtables_rule_match **matches)
310{
311#ifndef NO_SHARED_LIBS
312	struct stat sb;
313#endif
314	struct xtables_match *ptr;
315	const char *icmp6 = "icmp6";
316
317	/* This is ugly as hell. Nonetheless, there is no way of changing
318	 * this without hurting backwards compatibility */
319	if ( (strcmp(name,"icmpv6") == 0) ||
320	     (strcmp(name,"ipv6-icmp") == 0) ||
321	     (strcmp(name,"icmp6") == 0) )
322		name = icmp6;
323
324	for (ptr = xtables_matches; ptr; ptr = ptr->next) {
325		if (strcmp(name, ptr->name) == 0) {
326			struct xtables_match *clone;
327
328			/* First match of this type: */
329			if (ptr->m == NULL)
330				break;
331
332			/* Second and subsequent clones */
333			clone = fw_malloc(sizeof(struct xtables_match));
334			memcpy(clone, ptr, sizeof(struct xtables_match));
335			clone->mflags = 0;
336			/* This is a clone: */
337			clone->next = clone;
338
339			ptr = clone;
340			break;
341		}
342	}
343
344#ifndef NO_SHARED_LIBS
345	if (!ptr && tryload != DONT_LOAD && tryload != DURING_LOAD) {
346		char path[strlen(lib_dir) + sizeof("/.so")
347			  + strlen(afinfo.libprefix) + strlen(name)];
348
349		sprintf(path, "%s/libxt_%s.so", lib_dir, name);
350		if (dlopen(path, RTLD_NOW) != NULL)
351			/* Found library.  If it didn't register itself,
352			   maybe they specified target as match. */
353			ptr = find_match(name, DONT_LOAD, NULL);
354		else if (stat(path, &sb) == 0)
355			fprintf(stderr, "%s: %s\n", path, dlerror());
356
357		if (ptr == NULL) {
358			sprintf(path, "%s/%s%s.so", lib_dir, afinfo.libprefix,
359				name);
360			if (dlopen(path, RTLD_NOW) != NULL)
361				ptr = find_match(name, DONT_LOAD, NULL);
362			else if (stat(path, &sb) == 0)
363				fprintf(stderr, "%s: %s\n", path, dlerror());
364		}
365
366		if (ptr == NULL && tryload == LOAD_MUST_SUCCEED)
367			exit_error(PARAMETER_PROBLEM,
368				   "Couldn't load match `%s':%s\n",
369				   name, dlerror());
370	}
371#else
372	if (ptr && !ptr->loaded) {
373		if (tryload != DONT_LOAD)
374			ptr->loaded = 1;
375		else
376			ptr = NULL;
377	}
378	if(!ptr && (tryload == LOAD_MUST_SUCCEED)) {
379		exit_error(PARAMETER_PROBLEM,
380			   "Couldn't find match `%s'\n", name);
381	}
382#endif
383
384	if (ptr && matches) {
385		struct xtables_rule_match **i;
386		struct xtables_rule_match *newentry;
387
388		newentry = fw_malloc(sizeof(struct xtables_rule_match));
389
390		for (i = matches; *i; i = &(*i)->next) {
391			if (strcmp(name, (*i)->match->name) == 0)
392				(*i)->completed = 1;
393		}
394		newentry->match = ptr;
395		newentry->completed = 0;
396		newentry->next = NULL;
397		*i = newentry;
398	}
399
400	return ptr;
401}
402
403
404struct xtables_target *find_target(const char *name, enum xt_tryload tryload)
405{
406#ifndef NO_SHARED_LIBS
407	struct stat sb;
408#endif
409	struct xtables_target *ptr;
410
411	/* Standard target? */
412	if (strcmp(name, "") == 0
413	    || strcmp(name, XTC_LABEL_ACCEPT) == 0
414	    || strcmp(name, XTC_LABEL_DROP) == 0
415	    || strcmp(name, XTC_LABEL_QUEUE) == 0
416	    || strcmp(name, XTC_LABEL_RETURN) == 0)
417		name = "standard";
418
419	for (ptr = xtables_targets; ptr; ptr = ptr->next) {
420		if (strcmp(name, ptr->name) == 0)
421			break;
422	}
423
424#ifndef NO_SHARED_LIBS
425	if (!ptr && tryload != DONT_LOAD && tryload != DURING_LOAD) {
426		char path[strlen(lib_dir) + sizeof("/.so")
427			  + strlen(afinfo.libprefix) + strlen(name)];
428
429		sprintf(path, "%s/libxt_%s.so", lib_dir, name);
430		if (dlopen(path, RTLD_NOW) != NULL)
431			/* Found library.  If it didn't register itself,
432			   maybe they specified match as a target. */
433			ptr = find_target(name, DONT_LOAD);
434		else if (stat(path, &sb) == 0)
435			fprintf(stderr, "%s: %s\n", path, dlerror());
436
437		if (ptr == NULL) {
438			sprintf(path, "%s/%s%s.so", lib_dir, afinfo.libprefix,
439				name);
440			if (dlopen(path, RTLD_NOW) != NULL)
441				ptr = find_target(name, DONT_LOAD);
442			else if (stat(path, &sb) == 0)
443				fprintf(stderr, "%s: %s\n", path, dlerror());
444		}
445		if (ptr == NULL && tryload == LOAD_MUST_SUCCEED)
446			exit_error(PARAMETER_PROBLEM,
447				   "Couldn't load target `%s':%s\n",
448				   name, dlerror());
449	}
450#else
451	if (ptr && !ptr->loaded) {
452		if (tryload != DONT_LOAD)
453			ptr->loaded = 1;
454		else
455			ptr = NULL;
456	}
457	if(!ptr && (tryload == LOAD_MUST_SUCCEED)) {
458		exit_error(PARAMETER_PROBLEM,
459			   "Couldn't find target `%s'\n", name);
460	}
461#endif
462
463	if (ptr)
464		ptr->used = 1;
465
466	return ptr;
467}
468
469static int compatible_revision(const char *name, u_int8_t revision, int opt)
470{
471	struct xt_get_revision rev;
472	socklen_t s = sizeof(rev);
473	int max_rev, sockfd;
474
475	sockfd = socket(afinfo.family, SOCK_RAW, IPPROTO_RAW);
476	if (sockfd < 0) {
477		if (errno == EPERM) {
478			/* revision 0 is always supported. */
479			if (revision != 0)
480				fprintf(stderr, "Could not determine whether "
481						"revision %u is supported, "
482						"assuming it is.\n",
483					revision);
484			return 1;
485		}
486		fprintf(stderr, "Could not open socket to kernel: %s\n",
487			strerror(errno));
488		exit(1);
489	}
490
491	load_xtables_ko(modprobe, 1);
492
493	strcpy(rev.name, name);
494	rev.revision = revision;
495
496	max_rev = getsockopt(sockfd, afinfo.ipproto, opt, &rev, &s);
497	if (max_rev < 0) {
498		/* Definitely don't support this? */
499		if (errno == ENOENT || errno == EPROTONOSUPPORT) {
500			close(sockfd);
501			return 0;
502		} else if (errno == ENOPROTOOPT) {
503			close(sockfd);
504			/* Assume only revision 0 support (old kernel) */
505			return (revision == 0);
506		} else {
507			fprintf(stderr, "getsockopt failed strangely: %s\n",
508				strerror(errno));
509			exit(1);
510		}
511	}
512	close(sockfd);
513	return 1;
514}
515
516
517static int compatible_match_revision(const char *name, u_int8_t revision)
518{
519	return compatible_revision(name, revision, afinfo.so_rev_match);
520}
521
522static int compatible_target_revision(const char *name, u_int8_t revision)
523{
524	return compatible_revision(name, revision, afinfo.so_rev_target);
525}
526
527void xtables_register_match(struct xtables_match *me)
528{
529	struct xtables_match **i, *old;
530
531	if (strcmp(me->version, program_version) != 0) {
532		fprintf(stderr, "%s: match `%s' v%s (I'm v%s).\n",
533			program_name, me->name, me->version, program_version);
534		exit(1);
535	}
536
537	/* Revision field stole a char from name. */
538	if (strlen(me->name) >= XT_FUNCTION_MAXNAMELEN-1) {
539		fprintf(stderr, "%s: target `%s' has invalid name\n",
540			program_name, me->name);
541		exit(1);
542	}
543
544	if (me->family >= NPROTO) {
545		fprintf(stderr,
546			"%s: BUG: match %s has invalid protocol family\n",
547			program_name, me->name);
548		exit(1);
549	}
550
551	/* ignore not interested match */
552	if (me->family != afinfo.family)
553		return;
554
555	old = find_match(me->name, DURING_LOAD, NULL);
556	if (old) {
557		if (old->revision == me->revision) {
558			fprintf(stderr,
559				"%s: match `%s' already registered.\n",
560				program_name, me->name);
561			exit(1);
562		}
563
564		/* Now we have two (or more) options, check compatibility. */
565		if (compatible_match_revision(old->name, old->revision)
566		    && old->revision > me->revision)
567			return;
568
569		/* Replace if compatible. */
570		if (!compatible_match_revision(me->name, me->revision))
571			return;
572
573		/* Delete old one. */
574		for (i = &xtables_matches; *i!=old; i = &(*i)->next);
575		*i = old->next;
576	}
577
578	if (me->size != XT_ALIGN(me->size)) {
579		fprintf(stderr, "%s: match `%s' has invalid size %u.\n",
580			program_name, me->name, (unsigned int)me->size);
581		exit(1);
582	}
583
584	/* Append to list. */
585	for (i = &xtables_matches; *i; i = &(*i)->next);
586	me->next = NULL;
587	*i = me;
588
589	me->m = NULL;
590	me->mflags = 0;
591}
592
593void xtables_register_target(struct xtables_target *me)
594{
595	struct xtables_target *old;
596
597	if (strcmp(me->version, program_version) != 0) {
598		fprintf(stderr, "%s: target `%s' v%s (I'm v%s).\n",
599			program_name, me->name, me->version, program_version);
600		exit(1);
601	}
602
603	/* Revision field stole a char from name. */
604	if (strlen(me->name) >= XT_FUNCTION_MAXNAMELEN-1) {
605		fprintf(stderr, "%s: target `%s' has invalid name\n",
606			program_name, me->name);
607		exit(1);
608	}
609
610	if (me->family >= NPROTO) {
611		fprintf(stderr,
612			"%s: BUG: target %s has invalid protocol family\n",
613			program_name, me->name);
614		exit(1);
615	}
616
617	/* ignore not interested target */
618	if (me->family != afinfo.family)
619		return;
620
621	old = find_target(me->name, DURING_LOAD);
622	if (old) {
623		struct xtables_target **i;
624
625		if (old->revision == me->revision) {
626			fprintf(stderr,
627				"%s: target `%s' already registered.\n",
628				program_name, me->name);
629			exit(1);
630		}
631
632		/* Now we have two (or more) options, check compatibility. */
633		if (compatible_target_revision(old->name, old->revision)
634		    && old->revision > me->revision)
635			return;
636
637		/* Replace if compatible. */
638		if (!compatible_target_revision(me->name, me->revision))
639			return;
640
641		/* Delete old one. */
642		for (i = &xtables_targets; *i!=old; i = &(*i)->next);
643		*i = old->next;
644	}
645
646	if (me->size != XT_ALIGN(me->size)) {
647		fprintf(stderr, "%s: target `%s' has invalid size %u.\n",
648			program_name, me->name, (unsigned int)me->size);
649		exit(1);
650	}
651
652	/* Prepend to list. */
653	me->next = xtables_targets;
654	xtables_targets = me;
655	me->t = NULL;
656	me->tflags = 0;
657}
658
659void param_act(unsigned int status, const char *p1, ...)
660{
661	const char *p2, *p3;
662	va_list args;
663	bool b;
664
665	va_start(args, p1);
666
667	switch (status) {
668	case P_ONLY_ONCE:
669		p2 = va_arg(args, const char *);
670		b  = va_arg(args, unsigned int);
671		if (!b)
672			return;
673		exit_error(PARAMETER_PROBLEM,
674		           "%s: \"%s\" option may only be specified once",
675		           p1, p2);
676		break;
677	case P_NO_INVERT:
678		p2 = va_arg(args, const char *);
679		b  = va_arg(args, unsigned int);
680		if (!b)
681			return;
682		exit_error(PARAMETER_PROBLEM,
683		           "%s: \"%s\" option cannot be inverted", p1, p2);
684		break;
685	case P_BAD_VALUE:
686		p2 = va_arg(args, const char *);
687		p3 = va_arg(args, const char *);
688		exit_error(PARAMETER_PROBLEM,
689		           "%s: Bad value for \"%s\" option: \"%s\"",
690		           p1, p2, p3);
691		break;
692	case P_ONE_ACTION:
693		b = va_arg(args, unsigned int);
694		if (!b)
695			return;
696		exit_error(PARAMETER_PROBLEM,
697		           "%s: At most one action is possible", p1);
698		break;
699	default:
700		exit_error(status, p1, args);
701		break;
702	}
703
704	va_end(args);
705}
706
707const char *ipaddr_to_numeric(const struct in_addr *addrp)
708{
709	static char buf[20];
710	const unsigned char *bytep = (const void *)&addrp->s_addr;
711
712	sprintf(buf, "%u.%u.%u.%u", bytep[0], bytep[1], bytep[2], bytep[3]);
713	return buf;
714}
715
716static const char *ipaddr_to_host(const struct in_addr *addr)
717{
718	struct hostent *host;
719
720	host = gethostbyaddr(addr, sizeof(struct in_addr), AF_INET);
721	if (host == NULL)
722		return NULL;
723
724	return host->h_name;
725}
726
727static const char *ipaddr_to_network(const struct in_addr *addr)
728{
729	struct netent *net;
730
731	if ((net = getnetbyaddr(ntohl(addr->s_addr), AF_INET)) != NULL)
732		return net->n_name;
733
734	return NULL;
735}
736
737const char *ipaddr_to_anyname(const struct in_addr *addr)
738{
739	const char *name;
740
741	if ((name = ipaddr_to_host(addr)) != NULL ||
742	    (name = ipaddr_to_network(addr)) != NULL)
743		return name;
744
745	return ipaddr_to_numeric(addr);
746}
747
748const char *ipmask_to_numeric(const struct in_addr *mask)
749{
750	static char buf[20];
751	uint32_t maskaddr, bits;
752	int i;
753
754	maskaddr = ntohl(mask->s_addr);
755
756	if (maskaddr == 0xFFFFFFFFL)
757		/* we don't want to see "/32" */
758		return "";
759
760	i = 32;
761	bits = 0xFFFFFFFEL;
762	while (--i >= 0 && maskaddr != bits)
763		bits <<= 1;
764	if (i >= 0)
765		sprintf(buf, "/%d", i);
766	else
767		/* mask was not a decent combination of 1's and 0's */
768		sprintf(buf, "/%s", ipaddr_to_numeric(mask));
769
770	return buf;
771}
772
773static struct in_addr *__numeric_to_ipaddr(const char *dotted, bool is_mask)
774{
775	static struct in_addr addr;
776	unsigned char *addrp;
777	unsigned int onebyte;
778	char buf[20], *p, *q;
779	int i;
780
781	/* copy dotted string, because we need to modify it */
782	strncpy(buf, dotted, sizeof(buf) - 1);
783	buf[sizeof(buf) - 1] = '\0';
784	addrp = (void *)&addr.s_addr;
785
786	p = buf;
787	for (i = 0; i < 3; ++i) {
788		if ((q = strchr(p, '.')) == NULL) {
789			if (is_mask)
790				return NULL;
791
792			/* autocomplete, this is a network address */
793			if (!strtonum(p, NULL, &onebyte, 0, 255))
794				return NULL;
795
796			addrp[i] = onebyte;
797			while (i < 3)
798				addrp[++i] = 0;
799
800			return &addr;
801		}
802
803		*q = '\0';
804		if (!strtonum(p, NULL, &onebyte, 0, 255))
805			return NULL;
806
807		addrp[i] = onebyte;
808		p = q + 1;
809	}
810
811	/* we have checked 3 bytes, now we check the last one */
812	if (!strtonum(p, NULL, &onebyte, 0, 255))
813		return NULL;
814
815	addrp[3] = onebyte;
816	return &addr;
817}
818
819struct in_addr *numeric_to_ipaddr(const char *dotted)
820{
821	return __numeric_to_ipaddr(dotted, false);
822}
823
824struct in_addr *numeric_to_ipmask(const char *dotted)
825{
826	return __numeric_to_ipaddr(dotted, true);
827}
828
829static struct in_addr *network_to_ipaddr(const char *name)
830{
831	static struct in_addr addr;
832	struct netent *net;
833
834	if ((net = getnetbyname(name)) != NULL) {
835		if (net->n_addrtype != AF_INET)
836			return NULL;
837		addr.s_addr = htonl(net->n_net);
838		return &addr;
839	}
840
841	return NULL;
842}
843
844static struct in_addr *host_to_ipaddr(const char *name, unsigned int *naddr)
845{
846	struct hostent *host;
847	struct in_addr *addr;
848	unsigned int i;
849
850	*naddr = 0;
851	if ((host = gethostbyname(name)) != NULL) {
852		if (host->h_addrtype != AF_INET ||
853		    host->h_length != sizeof(struct in_addr))
854			return NULL;
855
856		while (host->h_addr_list[*naddr] != NULL)
857			++*naddr;
858		addr = fw_calloc(*naddr, sizeof(struct in_addr) * *naddr);
859		for (i = 0; i < *naddr; i++)
860			memcpy(&addr[i], host->h_addr_list[i],
861			       sizeof(struct in_addr));
862		return addr;
863	}
864
865	return NULL;
866}
867
868static struct in_addr *
869ipparse_hostnetwork(const char *name, unsigned int *naddrs)
870{
871	struct in_addr *addrptmp, *addrp;
872
873	if ((addrptmp = numeric_to_ipaddr(name)) != NULL ||
874	    (addrptmp = network_to_ipaddr(name)) != NULL) {
875		addrp = fw_malloc(sizeof(struct in_addr));
876		memcpy(addrp, addrptmp, sizeof(*addrp));
877		*naddrs = 1;
878		return addrp;
879	}
880	if ((addrptmp = host_to_ipaddr(name, naddrs)) != NULL)
881		return addrptmp;
882
883	exit_error(PARAMETER_PROBLEM, "host/network `%s' not found", name);
884}
885
886static struct in_addr *parse_ipmask(const char *mask)
887{
888	static struct in_addr maskaddr;
889	struct in_addr *addrp;
890	unsigned int bits;
891
892	if (mask == NULL) {
893		/* no mask at all defaults to 32 bits */
894		maskaddr.s_addr = 0xFFFFFFFF;
895		return &maskaddr;
896	}
897	if ((addrp = numeric_to_ipmask(mask)) != NULL)
898		/* dotted_to_addr already returns a network byte order addr */
899		return addrp;
900	if (string_to_number(mask, 0, 32, &bits) == -1)
901		exit_error(PARAMETER_PROBLEM,
902			   "invalid mask `%s' specified", mask);
903	if (bits != 0) {
904		maskaddr.s_addr = htonl(0xFFFFFFFF << (32 - bits));
905		return &maskaddr;
906	}
907
908	maskaddr.s_addr = 0U;
909	return &maskaddr;
910}
911
912void ipparse_hostnetworkmask(const char *name, struct in_addr **addrpp,
913                             struct in_addr *maskp, unsigned int *naddrs)
914{
915	unsigned int i, j, k, n;
916	struct in_addr *addrp;
917	char buf[256], *p;
918
919	strncpy(buf, name, sizeof(buf) - 1);
920	buf[sizeof(buf) - 1] = '\0';
921	if ((p = strrchr(buf, '/')) != NULL) {
922		*p = '\0';
923		addrp = parse_ipmask(p + 1);
924	} else {
925		addrp = parse_ipmask(NULL);
926	}
927	memcpy(maskp, addrp, sizeof(*maskp));
928
929	/* if a null mask is given, the name is ignored, like in "any/0" */
930	if (maskp->s_addr == 0U)
931		strcpy(buf, "0.0.0.0");
932
933	addrp = *addrpp = ipparse_hostnetwork(buf, naddrs);
934	n = *naddrs;
935	for (i = 0, j = 0; i < n; ++i) {
936		addrp[j++].s_addr &= maskp->s_addr;
937		for (k = 0; k < j - 1; ++k)
938			if (addrp[k].s_addr == addrp[j-1].s_addr) {
939				--*naddrs;
940				--j;
941				break;
942			}
943	}
944}
945
946const char *ip6addr_to_numeric(const struct in6_addr *addrp)
947{
948	/* 0000:0000:0000:0000:0000:000.000.000.000
949	 * 0000:0000:0000:0000:0000:0000:0000:0000 */
950	static char buf[50+1];
951	return inet_ntop(AF_INET6, addrp, buf, sizeof(buf));
952}
953
954static const char *ip6addr_to_host(const struct in6_addr *addr)
955{
956	static char hostname[NI_MAXHOST];
957	struct sockaddr_in6 saddr;
958	int err;
959
960	memset(&saddr, 0, sizeof(struct sockaddr_in6));
961	memcpy(&saddr.sin6_addr, addr, sizeof(*addr));
962	saddr.sin6_family = AF_INET6;
963
964	err = getnameinfo((const void *)&saddr, sizeof(struct sockaddr_in6),
965	      hostname, sizeof(hostname) - 1, NULL, 0, 0);
966	if (err != 0) {
967#ifdef DEBUG
968		fprintf(stderr,"IP2Name: %s\n",gai_strerror(err));
969#endif
970		return NULL;
971	}
972
973#ifdef DEBUG
974	fprintf (stderr, "\naddr2host: %s\n", hostname);
975#endif
976	return hostname;
977}
978
979const char *ip6addr_to_anyname(const struct in6_addr *addr)
980{
981	const char *name;
982
983	if ((name = ip6addr_to_host(addr)) != NULL)
984		return name;
985
986	return ip6addr_to_numeric(addr);
987}
988
989static int ip6addr_prefix_length(const struct in6_addr *k)
990{
991	unsigned int bits = 0;
992	uint32_t a, b, c, d;
993
994	a = k->s6_addr32[0];
995	b = k->s6_addr32[1];
996	c = k->s6_addr32[2];
997	d = k->s6_addr32[3];
998	while (a & 0x80000000U) {
999		++bits;
1000		a <<= 1;
1001		a  |= (b >> 31) & 1;
1002		b <<= 1;
1003		b  |= (c >> 31) & 1;
1004		c <<= 1;
1005		c  |= (d >> 31) & 1;
1006		d <<= 1;
1007	}
1008	if (a != 0 || b != 0 || c != 0 || d != 0)
1009		return -1;
1010	return bits;
1011}
1012
1013const char *ip6mask_to_numeric(const struct in6_addr *addrp)
1014{
1015	static char buf[50+2];
1016	int l = ip6addr_prefix_length(addrp);
1017
1018	if (l == -1) {
1019		strcpy(buf, "/");
1020		strcat(buf, ip6addr_to_numeric(addrp));
1021		return buf;
1022	}
1023	sprintf(buf, "/%d", l);
1024	return buf;
1025}
1026
1027struct in6_addr *numeric_to_ip6addr(const char *num)
1028{
1029	static struct in6_addr ap;
1030	int err;
1031
1032	if ((err = inet_pton(AF_INET6, num, &ap)) == 1)
1033		return &ap;
1034#ifdef DEBUG
1035	fprintf(stderr, "\nnumeric2addr: %d\n", err);
1036#endif
1037	return NULL;
1038}
1039
1040static struct in6_addr *
1041host_to_ip6addr(const char *name, unsigned int *naddr)
1042{
1043	static struct in6_addr *addr;
1044	struct addrinfo hints;
1045	struct addrinfo *res;
1046	int err;
1047
1048	memset(&hints, 0, sizeof(hints));
1049	hints.ai_flags    = AI_CANONNAME;
1050	hints.ai_family   = AF_INET6;
1051	hints.ai_socktype = SOCK_RAW;
1052	hints.ai_protocol = IPPROTO_IPV6;
1053	hints.ai_next     = NULL;
1054
1055	*naddr = 0;
1056	if ((err = getaddrinfo(name, NULL, &hints, &res)) != 0) {
1057#ifdef DEBUG
1058		fprintf(stderr,"Name2IP: %s\n",gai_strerror(err));
1059#endif
1060		return NULL;
1061	} else {
1062		if (res->ai_family != AF_INET6 ||
1063		    res->ai_addrlen != sizeof(struct sockaddr_in6))
1064			return NULL;
1065
1066#ifdef DEBUG
1067		fprintf(stderr, "resolved: len=%d  %s ", res->ai_addrlen,
1068		        ip6addr_to_numeric(&((struct sockaddr_in6 *)res->ai_addr)->sin6_addr));
1069#endif
1070		/* Get the first element of the address-chain */
1071		addr = fw_malloc(sizeof(struct in6_addr));
1072		memcpy(addr, &((const struct sockaddr_in6 *)res->ai_addr)->sin6_addr,
1073		       sizeof(struct in6_addr));
1074		freeaddrinfo(res);
1075		*naddr = 1;
1076		return addr;
1077	}
1078
1079	return NULL;
1080}
1081
1082static struct in6_addr *network_to_ip6addr(const char *name)
1083{
1084	/*	abort();*/
1085	/* TODO: not implemented yet, but the exception breaks the
1086	 *       name resolvation */
1087	return NULL;
1088}
1089
1090static struct in6_addr *
1091ip6parse_hostnetwork(const char *name, unsigned int *naddrs)
1092{
1093	struct in6_addr *addrp, *addrptmp;
1094
1095	if ((addrptmp = numeric_to_ip6addr(name)) != NULL ||
1096	    (addrptmp = network_to_ip6addr(name)) != NULL) {
1097		addrp = fw_malloc(sizeof(struct in6_addr));
1098		memcpy(addrp, addrptmp, sizeof(*addrp));
1099		*naddrs = 1;
1100		return addrp;
1101	}
1102	if ((addrp = host_to_ip6addr(name, naddrs)) != NULL)
1103		return addrp;
1104
1105	exit_error(PARAMETER_PROBLEM, "host/network `%s' not found", name);
1106}
1107
1108static struct in6_addr *parse_ip6mask(char *mask)
1109{
1110	static struct in6_addr maskaddr;
1111	struct in6_addr *addrp;
1112	unsigned int bits;
1113
1114	if (mask == NULL) {
1115		/* no mask at all defaults to 128 bits */
1116		memset(&maskaddr, 0xff, sizeof maskaddr);
1117		return &maskaddr;
1118	}
1119	if ((addrp = numeric_to_ip6addr(mask)) != NULL)
1120		return addrp;
1121	if (string_to_number(mask, 0, 128, &bits) == -1)
1122		exit_error(PARAMETER_PROBLEM,
1123			   "invalid mask `%s' specified", mask);
1124	if (bits != 0) {
1125		char *p = (void *)&maskaddr;
1126		memset(p, 0xff, bits / 8);
1127		memset(p + (bits / 8) + 1, 0, (128 - bits) / 8);
1128		p[bits/8] = 0xff << (8 - (bits & 7));
1129		return &maskaddr;
1130	}
1131
1132	memset(&maskaddr, 0, sizeof(maskaddr));
1133	return &maskaddr;
1134}
1135
1136void ip6parse_hostnetworkmask(const char *name, struct in6_addr **addrpp,
1137                              struct in6_addr *maskp, unsigned int *naddrs)
1138{
1139	struct in6_addr *addrp;
1140	unsigned int i, j, k, n;
1141	char buf[256], *p;
1142
1143	strncpy(buf, name, sizeof(buf) - 1);
1144	buf[sizeof(buf)-1] = '\0';
1145	if ((p = strrchr(buf, '/')) != NULL) {
1146		*p = '\0';
1147		addrp = parse_ip6mask(p + 1);
1148	} else {
1149		addrp = parse_ip6mask(NULL);
1150	}
1151	memcpy(maskp, addrp, sizeof(*maskp));
1152
1153	/* if a null mask is given, the name is ignored, like in "any/0" */
1154	if (memcmp(maskp, &in6addr_any, sizeof(in6addr_any)) == 0)
1155		strcpy(buf, "::");
1156
1157	addrp = *addrpp = ip6parse_hostnetwork(buf, naddrs);
1158	n = *naddrs;
1159	for (i = 0, j = 0; i < n; ++i) {
1160		for (k = 0; k < 4; ++k)
1161			addrp[j].in6_u.u6_addr32[k] &= maskp->in6_u.u6_addr32[k];
1162		++j;
1163		for (k = 0; k < j - 1; ++k)
1164			if (IN6_ARE_ADDR_EQUAL(&addrp[k], &addrp[j - 1])) {
1165				--*naddrs;
1166				--j;
1167				break;
1168			}
1169	}
1170}
1171
1172void save_string(const char *value)
1173{
1174	static const char no_quote_chars[] = "_-0123456789"
1175		"abcdefghijklmnopqrstuvwxyz"
1176		"ABCDEFGHIJKLMNOPQRSTUVWXYZ";
1177	static const char escape_chars[] = "\"\\'";
1178	size_t length;
1179	const char *p;
1180
1181	length = strcspn(value, no_quote_chars);
1182	if (length > 0 && value[length] == 0) {
1183		/* no quoting required */
1184		fputs(value, stdout);
1185		putchar(' ');
1186	} else {
1187		/* there is at least one dangerous character in the
1188		   value, which we have to quote.  Write double quotes
1189		   around the value and escape special characters with
1190		   a backslash */
1191		putchar('"');
1192
1193		for (p = strpbrk(value, escape_chars); p != NULL;
1194		     p = strpbrk(value, escape_chars)) {
1195			if (p > value)
1196				fwrite(value, 1, p - value, stdout);
1197			putchar('\\');
1198			putchar(*p);
1199			value = p + 1;
1200		}
1201
1202		/* print the rest and finish the double quoted
1203		   string */
1204		fputs(value, stdout);
1205		printf("\" ");
1206	}
1207}
1208