xtables.c revision cb25af809a8734c4766b6bfa4cca99596cbf01db
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_program = 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
308#ifndef NO_SHARED_LIBS
309static void *load_extension(const char *search_path, const char *prefix,
310    const char *name, bool is_target)
311{
312	const char *dir = search_path, *next;
313	void *ptr = NULL;
314	struct stat sb;
315	char path[256];
316
317	do {
318		next = strchr(dir, ':');
319		if (next == NULL)
320			next = dir + strlen(dir);
321		snprintf(path, sizeof(path), "%.*s/libxt_%s.so",
322		         (unsigned int)(next - dir), dir, name);
323
324		if (dlopen(path, RTLD_NOW) != NULL) {
325			/* Found library.  If it didn't register itself,
326			   maybe they specified target as match. */
327			if (is_target)
328				ptr = find_target(name, DONT_LOAD);
329			else
330				ptr = find_match(name, DONT_LOAD, NULL);
331		} else if (stat(path, &sb) == 0) {
332			fprintf(stderr, "%s: %s\n", path, dlerror());
333		}
334
335		if (ptr != NULL)
336			return ptr;
337
338		snprintf(path, sizeof(path), "%.*s/%s%s.so",
339		         (unsigned int)(next - dir), dir, prefix, name);
340		if (dlopen(path, RTLD_NOW) != NULL) {
341			if (is_target)
342				ptr = find_target(name, DONT_LOAD);
343			else
344				ptr = find_match(name, DONT_LOAD, NULL);
345		} else if (stat(path, &sb) == 0) {
346			fprintf(stderr, "%s: %s\n", path, dlerror());
347		}
348
349		if (ptr != NULL)
350			return ptr;
351
352		dir = next + 1;
353	} while (*next != '\0');
354
355	return NULL;
356}
357#endif
358
359struct xtables_match *find_match(const char *name, enum xt_tryload tryload,
360				 struct xtables_rule_match **matches)
361{
362	struct xtables_match *ptr;
363	const char *icmp6 = "icmp6";
364
365	/* This is ugly as hell. Nonetheless, there is no way of changing
366	 * this without hurting backwards compatibility */
367	if ( (strcmp(name,"icmpv6") == 0) ||
368	     (strcmp(name,"ipv6-icmp") == 0) ||
369	     (strcmp(name,"icmp6") == 0) )
370		name = icmp6;
371
372	for (ptr = xtables_matches; ptr; ptr = ptr->next) {
373		if (strcmp(name, ptr->name) == 0) {
374			struct xtables_match *clone;
375
376			/* First match of this type: */
377			if (ptr->m == NULL)
378				break;
379
380			/* Second and subsequent clones */
381			clone = fw_malloc(sizeof(struct xtables_match));
382			memcpy(clone, ptr, sizeof(struct xtables_match));
383			clone->mflags = 0;
384			/* This is a clone: */
385			clone->next = clone;
386
387			ptr = clone;
388			break;
389		}
390	}
391
392#ifndef NO_SHARED_LIBS
393	if (!ptr && tryload != DONT_LOAD && tryload != DURING_LOAD) {
394		ptr = load_extension(lib_dir, afinfo.libprefix, name, false);
395
396		if (ptr == NULL && tryload == LOAD_MUST_SUCCEED)
397			exit_error(PARAMETER_PROBLEM,
398				   "Couldn't load match `%s':%s\n",
399				   name, dlerror());
400	}
401#else
402	if (ptr && !ptr->loaded) {
403		if (tryload != DONT_LOAD)
404			ptr->loaded = 1;
405		else
406			ptr = NULL;
407	}
408	if(!ptr && (tryload == LOAD_MUST_SUCCEED)) {
409		exit_error(PARAMETER_PROBLEM,
410			   "Couldn't find match `%s'\n", name);
411	}
412#endif
413
414	if (ptr && matches) {
415		struct xtables_rule_match **i;
416		struct xtables_rule_match *newentry;
417
418		newentry = fw_malloc(sizeof(struct xtables_rule_match));
419
420		for (i = matches; *i; i = &(*i)->next) {
421			if (strcmp(name, (*i)->match->name) == 0)
422				(*i)->completed = 1;
423		}
424		newentry->match = ptr;
425		newentry->completed = 0;
426		newentry->next = NULL;
427		*i = newentry;
428	}
429
430	return ptr;
431}
432
433
434struct xtables_target *find_target(const char *name, enum xt_tryload tryload)
435{
436	struct xtables_target *ptr;
437
438	/* Standard target? */
439	if (strcmp(name, "") == 0
440	    || strcmp(name, XTC_LABEL_ACCEPT) == 0
441	    || strcmp(name, XTC_LABEL_DROP) == 0
442	    || strcmp(name, XTC_LABEL_QUEUE) == 0
443	    || strcmp(name, XTC_LABEL_RETURN) == 0)
444		name = "standard";
445
446	for (ptr = xtables_targets; ptr; ptr = ptr->next) {
447		if (strcmp(name, ptr->name) == 0)
448			break;
449	}
450
451#ifndef NO_SHARED_LIBS
452	if (!ptr && tryload != DONT_LOAD && tryload != DURING_LOAD) {
453		ptr = load_extension(lib_dir, afinfo.libprefix, name, true);
454
455		if (ptr == NULL && tryload == LOAD_MUST_SUCCEED)
456			exit_error(PARAMETER_PROBLEM,
457				   "Couldn't load target `%s':%s\n",
458				   name, dlerror());
459	}
460#else
461	if (ptr && !ptr->loaded) {
462		if (tryload != DONT_LOAD)
463			ptr->loaded = 1;
464		else
465			ptr = NULL;
466	}
467	if(!ptr && (tryload == LOAD_MUST_SUCCEED)) {
468		exit_error(PARAMETER_PROBLEM,
469			   "Couldn't find target `%s'\n", name);
470	}
471#endif
472
473	if (ptr)
474		ptr->used = 1;
475
476	return ptr;
477}
478
479static int compatible_revision(const char *name, u_int8_t revision, int opt)
480{
481	struct xt_get_revision rev;
482	socklen_t s = sizeof(rev);
483	int max_rev, sockfd;
484
485	sockfd = socket(afinfo.family, SOCK_RAW, IPPROTO_RAW);
486	if (sockfd < 0) {
487		if (errno == EPERM) {
488			/* revision 0 is always supported. */
489			if (revision != 0)
490				fprintf(stderr, "Could not determine whether "
491						"revision %u is supported, "
492						"assuming it is.\n",
493					revision);
494			return 1;
495		}
496		fprintf(stderr, "Could not open socket to kernel: %s\n",
497			strerror(errno));
498		exit(1);
499	}
500
501	load_xtables_ko(modprobe_program, 1);
502
503	strcpy(rev.name, name);
504	rev.revision = revision;
505
506	max_rev = getsockopt(sockfd, afinfo.ipproto, opt, &rev, &s);
507	if (max_rev < 0) {
508		/* Definitely don't support this? */
509		if (errno == ENOENT || errno == EPROTONOSUPPORT) {
510			close(sockfd);
511			return 0;
512		} else if (errno == ENOPROTOOPT) {
513			close(sockfd);
514			/* Assume only revision 0 support (old kernel) */
515			return (revision == 0);
516		} else {
517			fprintf(stderr, "getsockopt failed strangely: %s\n",
518				strerror(errno));
519			exit(1);
520		}
521	}
522	close(sockfd);
523	return 1;
524}
525
526
527static int compatible_match_revision(const char *name, u_int8_t revision)
528{
529	return compatible_revision(name, revision, afinfo.so_rev_match);
530}
531
532static int compatible_target_revision(const char *name, u_int8_t revision)
533{
534	return compatible_revision(name, revision, afinfo.so_rev_target);
535}
536
537void xtables_register_match(struct xtables_match *me)
538{
539	struct xtables_match **i, *old;
540
541	if (strcmp(me->version, program_version) != 0) {
542		fprintf(stderr, "%s: match `%s' v%s (I'm v%s).\n",
543			program_name, me->name, me->version, program_version);
544		exit(1);
545	}
546
547	/* Revision field stole a char from name. */
548	if (strlen(me->name) >= XT_FUNCTION_MAXNAMELEN-1) {
549		fprintf(stderr, "%s: target `%s' has invalid name\n",
550			program_name, me->name);
551		exit(1);
552	}
553
554	if (me->family >= NPROTO) {
555		fprintf(stderr,
556			"%s: BUG: match %s has invalid protocol family\n",
557			program_name, me->name);
558		exit(1);
559	}
560
561	/* ignore not interested match */
562	if (me->family != afinfo.family && me->family != AF_UNSPEC)
563		return;
564
565	old = find_match(me->name, DURING_LOAD, NULL);
566	if (old) {
567		if (old->revision == me->revision &&
568		    old->family == me->family) {
569			fprintf(stderr,
570				"%s: match `%s' already registered.\n",
571				program_name, me->name);
572			exit(1);
573		}
574
575		/* Now we have two (or more) options, check compatibility. */
576		if (compatible_match_revision(old->name, old->revision)
577		    && old->revision > me->revision)
578			return;
579
580		/* See if new match can be used. */
581		if (!compatible_match_revision(me->name, me->revision))
582			return;
583
584		/* Prefer !AF_UNSPEC over AF_UNSPEC for same revision. */
585		if (old->revision == me->revision && me->family == AF_UNSPEC)
586			return;
587
588		/* Delete old one. */
589		for (i = &xtables_matches; *i!=old; i = &(*i)->next);
590		*i = old->next;
591	}
592
593	if (me->size != XT_ALIGN(me->size)) {
594		fprintf(stderr, "%s: match `%s' has invalid size %u.\n",
595			program_name, me->name, (unsigned int)me->size);
596		exit(1);
597	}
598
599	/* Append to list. */
600	for (i = &xtables_matches; *i; i = &(*i)->next);
601	me->next = NULL;
602	*i = me;
603
604	me->m = NULL;
605	me->mflags = 0;
606}
607
608void xtables_register_target(struct xtables_target *me)
609{
610	struct xtables_target *old;
611
612	if (strcmp(me->version, program_version) != 0) {
613		fprintf(stderr, "%s: target `%s' v%s (I'm v%s).\n",
614			program_name, me->name, me->version, program_version);
615		exit(1);
616	}
617
618	/* Revision field stole a char from name. */
619	if (strlen(me->name) >= XT_FUNCTION_MAXNAMELEN-1) {
620		fprintf(stderr, "%s: target `%s' has invalid name\n",
621			program_name, me->name);
622		exit(1);
623	}
624
625	if (me->family >= NPROTO) {
626		fprintf(stderr,
627			"%s: BUG: target %s has invalid protocol family\n",
628			program_name, me->name);
629		exit(1);
630	}
631
632	/* ignore not interested target */
633	if (me->family != afinfo.family && me->family != AF_UNSPEC)
634		return;
635
636	old = find_target(me->name, DURING_LOAD);
637	if (old) {
638		struct xtables_target **i;
639
640		if (old->revision == me->revision &&
641		    old->family == me->family) {
642			fprintf(stderr,
643				"%s: target `%s' already registered.\n",
644				program_name, me->name);
645			exit(1);
646		}
647
648		/* Now we have two (or more) options, check compatibility. */
649		if (compatible_target_revision(old->name, old->revision)
650		    && old->revision > me->revision)
651			return;
652
653		/* See if new target can be used. */
654		if (!compatible_target_revision(me->name, me->revision))
655			return;
656
657		/* Prefer !AF_UNSPEC over AF_UNSPEC for same revision. */
658		if (old->revision == me->revision && me->family == AF_UNSPEC)
659			return;
660
661		/* Delete old one. */
662		for (i = &xtables_targets; *i!=old; i = &(*i)->next);
663		*i = old->next;
664	}
665
666	if (me->size != XT_ALIGN(me->size)) {
667		fprintf(stderr, "%s: target `%s' has invalid size %u.\n",
668			program_name, me->name, (unsigned int)me->size);
669		exit(1);
670	}
671
672	/* Prepend to list. */
673	me->next = xtables_targets;
674	xtables_targets = me;
675	me->t = NULL;
676	me->tflags = 0;
677}
678
679void param_act(unsigned int status, const char *p1, ...)
680{
681	const char *p2, *p3;
682	va_list args;
683	bool b;
684
685	va_start(args, p1);
686
687	switch (status) {
688	case P_ONLY_ONCE:
689		p2 = va_arg(args, const char *);
690		b  = va_arg(args, unsigned int);
691		if (!b)
692			return;
693		exit_error(PARAMETER_PROBLEM,
694		           "%s: \"%s\" option may only be specified once",
695		           p1, p2);
696		break;
697	case P_NO_INVERT:
698		p2 = va_arg(args, const char *);
699		b  = va_arg(args, unsigned int);
700		if (!b)
701			return;
702		exit_error(PARAMETER_PROBLEM,
703		           "%s: \"%s\" option cannot be inverted", p1, p2);
704		break;
705	case P_BAD_VALUE:
706		p2 = va_arg(args, const char *);
707		p3 = va_arg(args, const char *);
708		exit_error(PARAMETER_PROBLEM,
709		           "%s: Bad value for \"%s\" option: \"%s\"",
710		           p1, p2, p3);
711		break;
712	case P_ONE_ACTION:
713		b = va_arg(args, unsigned int);
714		if (!b)
715			return;
716		exit_error(PARAMETER_PROBLEM,
717		           "%s: At most one action is possible", p1);
718		break;
719	default:
720		exit_error(status, p1, args);
721		break;
722	}
723
724	va_end(args);
725}
726
727const char *ipaddr_to_numeric(const struct in_addr *addrp)
728{
729	static char buf[20];
730	const unsigned char *bytep = (const void *)&addrp->s_addr;
731
732	sprintf(buf, "%u.%u.%u.%u", bytep[0], bytep[1], bytep[2], bytep[3]);
733	return buf;
734}
735
736static const char *ipaddr_to_host(const struct in_addr *addr)
737{
738	struct hostent *host;
739
740	host = gethostbyaddr(addr, sizeof(struct in_addr), AF_INET);
741	if (host == NULL)
742		return NULL;
743
744	return host->h_name;
745}
746
747static const char *ipaddr_to_network(const struct in_addr *addr)
748{
749	struct netent *net;
750
751	if ((net = getnetbyaddr(ntohl(addr->s_addr), AF_INET)) != NULL)
752		return net->n_name;
753
754	return NULL;
755}
756
757const char *ipaddr_to_anyname(const struct in_addr *addr)
758{
759	const char *name;
760
761	if ((name = ipaddr_to_host(addr)) != NULL ||
762	    (name = ipaddr_to_network(addr)) != NULL)
763		return name;
764
765	return ipaddr_to_numeric(addr);
766}
767
768const char *ipmask_to_numeric(const struct in_addr *mask)
769{
770	static char buf[20];
771	uint32_t maskaddr, bits;
772	int i;
773
774	maskaddr = ntohl(mask->s_addr);
775
776	if (maskaddr == 0xFFFFFFFFL)
777		/* we don't want to see "/32" */
778		return "";
779
780	i = 32;
781	bits = 0xFFFFFFFEL;
782	while (--i >= 0 && maskaddr != bits)
783		bits <<= 1;
784	if (i >= 0)
785		sprintf(buf, "/%d", i);
786	else
787		/* mask was not a decent combination of 1's and 0's */
788		sprintf(buf, "/%s", ipaddr_to_numeric(mask));
789
790	return buf;
791}
792
793static struct in_addr *__numeric_to_ipaddr(const char *dotted, bool is_mask)
794{
795	static struct in_addr addr;
796	unsigned char *addrp;
797	unsigned int onebyte;
798	char buf[20], *p, *q;
799	int i;
800
801	/* copy dotted string, because we need to modify it */
802	strncpy(buf, dotted, sizeof(buf) - 1);
803	buf[sizeof(buf) - 1] = '\0';
804	addrp = (void *)&addr.s_addr;
805
806	p = buf;
807	for (i = 0; i < 3; ++i) {
808		if ((q = strchr(p, '.')) == NULL) {
809			if (is_mask)
810				return NULL;
811
812			/* autocomplete, this is a network address */
813			if (!strtonum(p, NULL, &onebyte, 0, 255))
814				return NULL;
815
816			addrp[i] = onebyte;
817			while (i < 3)
818				addrp[++i] = 0;
819
820			return &addr;
821		}
822
823		*q = '\0';
824		if (!strtonum(p, NULL, &onebyte, 0, 255))
825			return NULL;
826
827		addrp[i] = onebyte;
828		p = q + 1;
829	}
830
831	/* we have checked 3 bytes, now we check the last one */
832	if (!strtonum(p, NULL, &onebyte, 0, 255))
833		return NULL;
834
835	addrp[3] = onebyte;
836	return &addr;
837}
838
839struct in_addr *numeric_to_ipaddr(const char *dotted)
840{
841	return __numeric_to_ipaddr(dotted, false);
842}
843
844struct in_addr *numeric_to_ipmask(const char *dotted)
845{
846	return __numeric_to_ipaddr(dotted, true);
847}
848
849static struct in_addr *network_to_ipaddr(const char *name)
850{
851	static struct in_addr addr;
852	struct netent *net;
853
854	if ((net = getnetbyname(name)) != NULL) {
855		if (net->n_addrtype != AF_INET)
856			return NULL;
857		addr.s_addr = htonl(net->n_net);
858		return &addr;
859	}
860
861	return NULL;
862}
863
864static struct in_addr *host_to_ipaddr(const char *name, unsigned int *naddr)
865{
866	struct hostent *host;
867	struct in_addr *addr;
868	unsigned int i;
869
870	*naddr = 0;
871	if ((host = gethostbyname(name)) != NULL) {
872		if (host->h_addrtype != AF_INET ||
873		    host->h_length != sizeof(struct in_addr))
874			return NULL;
875
876		while (host->h_addr_list[*naddr] != NULL)
877			++*naddr;
878		addr = fw_calloc(*naddr, sizeof(struct in_addr) * *naddr);
879		for (i = 0; i < *naddr; i++)
880			memcpy(&addr[i], host->h_addr_list[i],
881			       sizeof(struct in_addr));
882		return addr;
883	}
884
885	return NULL;
886}
887
888static struct in_addr *
889ipparse_hostnetwork(const char *name, unsigned int *naddrs)
890{
891	struct in_addr *addrptmp, *addrp;
892
893	if ((addrptmp = numeric_to_ipaddr(name)) != NULL ||
894	    (addrptmp = network_to_ipaddr(name)) != NULL) {
895		addrp = fw_malloc(sizeof(struct in_addr));
896		memcpy(addrp, addrptmp, sizeof(*addrp));
897		*naddrs = 1;
898		return addrp;
899	}
900	if ((addrptmp = host_to_ipaddr(name, naddrs)) != NULL)
901		return addrptmp;
902
903	exit_error(PARAMETER_PROBLEM, "host/network `%s' not found", name);
904}
905
906static struct in_addr *parse_ipmask(const char *mask)
907{
908	static struct in_addr maskaddr;
909	struct in_addr *addrp;
910	unsigned int bits;
911
912	if (mask == NULL) {
913		/* no mask at all defaults to 32 bits */
914		maskaddr.s_addr = 0xFFFFFFFF;
915		return &maskaddr;
916	}
917	if ((addrp = numeric_to_ipmask(mask)) != NULL)
918		/* dotted_to_addr already returns a network byte order addr */
919		return addrp;
920	if (string_to_number(mask, 0, 32, &bits) == -1)
921		exit_error(PARAMETER_PROBLEM,
922			   "invalid mask `%s' specified", mask);
923	if (bits != 0) {
924		maskaddr.s_addr = htonl(0xFFFFFFFF << (32 - bits));
925		return &maskaddr;
926	}
927
928	maskaddr.s_addr = 0U;
929	return &maskaddr;
930}
931
932void ipparse_hostnetworkmask(const char *name, struct in_addr **addrpp,
933                             struct in_addr *maskp, unsigned int *naddrs)
934{
935	unsigned int i, j, k, n;
936	struct in_addr *addrp;
937	char buf[256], *p;
938
939	strncpy(buf, name, sizeof(buf) - 1);
940	buf[sizeof(buf) - 1] = '\0';
941	if ((p = strrchr(buf, '/')) != NULL) {
942		*p = '\0';
943		addrp = parse_ipmask(p + 1);
944	} else {
945		addrp = parse_ipmask(NULL);
946	}
947	memcpy(maskp, addrp, sizeof(*maskp));
948
949	/* if a null mask is given, the name is ignored, like in "any/0" */
950	if (maskp->s_addr == 0U)
951		strcpy(buf, "0.0.0.0");
952
953	addrp = *addrpp = ipparse_hostnetwork(buf, naddrs);
954	n = *naddrs;
955	for (i = 0, j = 0; i < n; ++i) {
956		addrp[j++].s_addr &= maskp->s_addr;
957		for (k = 0; k < j - 1; ++k)
958			if (addrp[k].s_addr == addrp[j-1].s_addr) {
959				--*naddrs;
960				--j;
961				break;
962			}
963	}
964}
965
966const char *ip6addr_to_numeric(const struct in6_addr *addrp)
967{
968	/* 0000:0000:0000:0000:0000:000.000.000.000
969	 * 0000:0000:0000:0000:0000:0000:0000:0000 */
970	static char buf[50+1];
971	return inet_ntop(AF_INET6, addrp, buf, sizeof(buf));
972}
973
974static const char *ip6addr_to_host(const struct in6_addr *addr)
975{
976	static char hostname[NI_MAXHOST];
977	struct sockaddr_in6 saddr;
978	int err;
979
980	memset(&saddr, 0, sizeof(struct sockaddr_in6));
981	memcpy(&saddr.sin6_addr, addr, sizeof(*addr));
982	saddr.sin6_family = AF_INET6;
983
984	err = getnameinfo((const void *)&saddr, sizeof(struct sockaddr_in6),
985	      hostname, sizeof(hostname) - 1, NULL, 0, 0);
986	if (err != 0) {
987#ifdef DEBUG
988		fprintf(stderr,"IP2Name: %s\n",gai_strerror(err));
989#endif
990		return NULL;
991	}
992
993#ifdef DEBUG
994	fprintf (stderr, "\naddr2host: %s\n", hostname);
995#endif
996	return hostname;
997}
998
999const char *ip6addr_to_anyname(const struct in6_addr *addr)
1000{
1001	const char *name;
1002
1003	if ((name = ip6addr_to_host(addr)) != NULL)
1004		return name;
1005
1006	return ip6addr_to_numeric(addr);
1007}
1008
1009static int ip6addr_prefix_length(const struct in6_addr *k)
1010{
1011	unsigned int bits = 0;
1012	uint32_t a, b, c, d;
1013
1014	a = k->s6_addr32[0];
1015	b = k->s6_addr32[1];
1016	c = k->s6_addr32[2];
1017	d = k->s6_addr32[3];
1018	while (a & 0x80000000U) {
1019		++bits;
1020		a <<= 1;
1021		a  |= (b >> 31) & 1;
1022		b <<= 1;
1023		b  |= (c >> 31) & 1;
1024		c <<= 1;
1025		c  |= (d >> 31) & 1;
1026		d <<= 1;
1027	}
1028	if (a != 0 || b != 0 || c != 0 || d != 0)
1029		return -1;
1030	return bits;
1031}
1032
1033const char *ip6mask_to_numeric(const struct in6_addr *addrp)
1034{
1035	static char buf[50+2];
1036	int l = ip6addr_prefix_length(addrp);
1037
1038	if (l == -1) {
1039		strcpy(buf, "/");
1040		strcat(buf, ip6addr_to_numeric(addrp));
1041		return buf;
1042	}
1043	sprintf(buf, "/%d", l);
1044	return buf;
1045}
1046
1047struct in6_addr *numeric_to_ip6addr(const char *num)
1048{
1049	static struct in6_addr ap;
1050	int err;
1051
1052	if ((err = inet_pton(AF_INET6, num, &ap)) == 1)
1053		return &ap;
1054#ifdef DEBUG
1055	fprintf(stderr, "\nnumeric2addr: %d\n", err);
1056#endif
1057	return NULL;
1058}
1059
1060static struct in6_addr *
1061host_to_ip6addr(const char *name, unsigned int *naddr)
1062{
1063	static struct in6_addr *addr;
1064	struct addrinfo hints;
1065	struct addrinfo *res;
1066	int err;
1067
1068	memset(&hints, 0, sizeof(hints));
1069	hints.ai_flags    = AI_CANONNAME;
1070	hints.ai_family   = AF_INET6;
1071	hints.ai_socktype = SOCK_RAW;
1072	hints.ai_protocol = IPPROTO_IPV6;
1073	hints.ai_next     = NULL;
1074
1075	*naddr = 0;
1076	if ((err = getaddrinfo(name, NULL, &hints, &res)) != 0) {
1077#ifdef DEBUG
1078		fprintf(stderr,"Name2IP: %s\n",gai_strerror(err));
1079#endif
1080		return NULL;
1081	} else {
1082		if (res->ai_family != AF_INET6 ||
1083		    res->ai_addrlen != sizeof(struct sockaddr_in6))
1084			return NULL;
1085
1086#ifdef DEBUG
1087		fprintf(stderr, "resolved: len=%d  %s ", res->ai_addrlen,
1088		        ip6addr_to_numeric(&((struct sockaddr_in6 *)res->ai_addr)->sin6_addr));
1089#endif
1090		/* Get the first element of the address-chain */
1091		addr = fw_malloc(sizeof(struct in6_addr));
1092		memcpy(addr, &((const struct sockaddr_in6 *)res->ai_addr)->sin6_addr,
1093		       sizeof(struct in6_addr));
1094		freeaddrinfo(res);
1095		*naddr = 1;
1096		return addr;
1097	}
1098
1099	return NULL;
1100}
1101
1102static struct in6_addr *network_to_ip6addr(const char *name)
1103{
1104	/*	abort();*/
1105	/* TODO: not implemented yet, but the exception breaks the
1106	 *       name resolvation */
1107	return NULL;
1108}
1109
1110static struct in6_addr *
1111ip6parse_hostnetwork(const char *name, unsigned int *naddrs)
1112{
1113	struct in6_addr *addrp, *addrptmp;
1114
1115	if ((addrptmp = numeric_to_ip6addr(name)) != NULL ||
1116	    (addrptmp = network_to_ip6addr(name)) != NULL) {
1117		addrp = fw_malloc(sizeof(struct in6_addr));
1118		memcpy(addrp, addrptmp, sizeof(*addrp));
1119		*naddrs = 1;
1120		return addrp;
1121	}
1122	if ((addrp = host_to_ip6addr(name, naddrs)) != NULL)
1123		return addrp;
1124
1125	exit_error(PARAMETER_PROBLEM, "host/network `%s' not found", name);
1126}
1127
1128static struct in6_addr *parse_ip6mask(char *mask)
1129{
1130	static struct in6_addr maskaddr;
1131	struct in6_addr *addrp;
1132	unsigned int bits;
1133
1134	if (mask == NULL) {
1135		/* no mask at all defaults to 128 bits */
1136		memset(&maskaddr, 0xff, sizeof maskaddr);
1137		return &maskaddr;
1138	}
1139	if ((addrp = numeric_to_ip6addr(mask)) != NULL)
1140		return addrp;
1141	if (string_to_number(mask, 0, 128, &bits) == -1)
1142		exit_error(PARAMETER_PROBLEM,
1143			   "invalid mask `%s' specified", mask);
1144	if (bits != 0) {
1145		char *p = (void *)&maskaddr;
1146		memset(p, 0xff, bits / 8);
1147		memset(p + (bits / 8) + 1, 0, (128 - bits) / 8);
1148		p[bits/8] = 0xff << (8 - (bits & 7));
1149		return &maskaddr;
1150	}
1151
1152	memset(&maskaddr, 0, sizeof(maskaddr));
1153	return &maskaddr;
1154}
1155
1156void ip6parse_hostnetworkmask(const char *name, struct in6_addr **addrpp,
1157                              struct in6_addr *maskp, unsigned int *naddrs)
1158{
1159	struct in6_addr *addrp;
1160	unsigned int i, j, k, n;
1161	char buf[256], *p;
1162
1163	strncpy(buf, name, sizeof(buf) - 1);
1164	buf[sizeof(buf)-1] = '\0';
1165	if ((p = strrchr(buf, '/')) != NULL) {
1166		*p = '\0';
1167		addrp = parse_ip6mask(p + 1);
1168	} else {
1169		addrp = parse_ip6mask(NULL);
1170	}
1171	memcpy(maskp, addrp, sizeof(*maskp));
1172
1173	/* if a null mask is given, the name is ignored, like in "any/0" */
1174	if (memcmp(maskp, &in6addr_any, sizeof(in6addr_any)) == 0)
1175		strcpy(buf, "::");
1176
1177	addrp = *addrpp = ip6parse_hostnetwork(buf, naddrs);
1178	n = *naddrs;
1179	for (i = 0, j = 0; i < n; ++i) {
1180		for (k = 0; k < 4; ++k)
1181			addrp[j].in6_u.u6_addr32[k] &= maskp->in6_u.u6_addr32[k];
1182		++j;
1183		for (k = 0; k < j - 1; ++k)
1184			if (IN6_ARE_ADDR_EQUAL(&addrp[k], &addrp[j - 1])) {
1185				--*naddrs;
1186				--j;
1187				break;
1188			}
1189	}
1190}
1191
1192void save_string(const char *value)
1193{
1194	static const char no_quote_chars[] = "_-0123456789"
1195		"abcdefghijklmnopqrstuvwxyz"
1196		"ABCDEFGHIJKLMNOPQRSTUVWXYZ";
1197	static const char escape_chars[] = "\"\\'";
1198	size_t length;
1199	const char *p;
1200
1201	length = strcspn(value, no_quote_chars);
1202	if (length > 0 && value[length] == 0) {
1203		/* no quoting required */
1204		fputs(value, stdout);
1205		putchar(' ');
1206	} else {
1207		/* there is at least one dangerous character in the
1208		   value, which we have to quote.  Write double quotes
1209		   around the value and escape special characters with
1210		   a backslash */
1211		putchar('"');
1212
1213		for (p = strpbrk(value, escape_chars); p != NULL;
1214		     p = strpbrk(value, escape_chars)) {
1215			if (p > value)
1216				fwrite(value, 1, p - value, stdout);
1217			putchar('\\');
1218			putchar(*p);
1219			value = p + 1;
1220		}
1221
1222		/* print the rest and finish the double quoted
1223		   string */
1224		fputs(value, stdout);
1225		printf("\" ");
1226	}
1227}
1228