1/*
2 *	Argument parser
3 *	Copyright © Jan Engelhardt, 2011
4 *
5 *	This program is free software; you can redistribute it and/or
6 *	modify it under the terms of the GNU General Public License as
7 *	published by the Free Software Foundation; either version 2 of
8 *	the License, or (at your option) any later version.
9 */
10#include <ctype.h>
11#include <errno.h>
12#include <getopt.h>
13#include <limits.h>
14#include <netdb.h>
15#include <stdbool.h>
16#include <stdint.h>
17#include <stdio.h>
18#include <stdlib.h>
19#include <string.h>
20#include <syslog.h>
21#include <arpa/inet.h>
22#include <netinet/ip.h>
23#include "xtables.h"
24#include "xshared.h"
25#ifndef IPTOS_NORMALSVC
26#	define IPTOS_NORMALSVC 0
27#endif
28
29#define XTOPT_MKPTR(cb) \
30	((void *)((char *)(cb)->data + (cb)->entry->ptroff))
31
32/**
33 * Simple key-value pairs for syslog levels
34 */
35struct syslog_level {
36	char name[8];
37	uint8_t level;
38};
39
40struct tos_value_mask {
41	uint8_t value, mask;
42};
43
44static const size_t xtopt_psize[] = {
45	/*
46	 * All types not listed here, and thus essentially being initialized to
47	 * zero have zero on purpose.
48	 */
49	[XTTYPE_UINT8]       = sizeof(uint8_t),
50	[XTTYPE_UINT16]      = sizeof(uint16_t),
51	[XTTYPE_UINT32]      = sizeof(uint32_t),
52	[XTTYPE_UINT64]      = sizeof(uint64_t),
53	[XTTYPE_UINT8RC]     = sizeof(uint8_t[2]),
54	[XTTYPE_UINT16RC]    = sizeof(uint16_t[2]),
55	[XTTYPE_UINT32RC]    = sizeof(uint32_t[2]),
56	[XTTYPE_UINT64RC]    = sizeof(uint64_t[2]),
57	[XTTYPE_DOUBLE]      = sizeof(double),
58	[XTTYPE_STRING]      = -1,
59	[XTTYPE_SYSLOGLEVEL] = sizeof(uint8_t),
60	[XTTYPE_HOST]        = sizeof(union nf_inet_addr),
61	[XTTYPE_HOSTMASK]    = sizeof(union nf_inet_addr),
62	[XTTYPE_PROTOCOL]    = sizeof(uint8_t),
63	[XTTYPE_PORT]        = sizeof(uint16_t),
64	[XTTYPE_PORTRC]      = sizeof(uint16_t[2]),
65	[XTTYPE_PLENMASK]    = sizeof(union nf_inet_addr),
66	[XTTYPE_ETHERMAC]    = sizeof(uint8_t[6]),
67};
68
69/**
70 * Creates getopt options from the x6-style option map, and assigns each a
71 * getopt id.
72 */
73struct option *
74xtables_options_xfrm(struct option *orig_opts, struct option *oldopts,
75		     const struct xt_option_entry *entry, unsigned int *offset)
76{
77	unsigned int num_orig, num_old = 0, num_new, i;
78	struct option *merge, *mp;
79
80	if (entry == NULL)
81		return oldopts;
82	for (num_orig = 0; orig_opts[num_orig].name != NULL; ++num_orig)
83		;
84	if (oldopts != NULL)
85		for (num_old = 0; oldopts[num_old].name != NULL; ++num_old)
86			;
87	for (num_new = 0; entry[num_new].name != NULL; ++num_new)
88		;
89
90	/*
91	 * Since @oldopts also has @orig_opts already (and does so at the
92	 * start), skip these entries.
93	 */
94	oldopts += num_orig;
95	num_old -= num_orig;
96
97	merge = malloc(sizeof(*mp) * (num_orig + num_old + num_new + 1));
98	if (merge == NULL)
99		return NULL;
100
101	/* Let the base options -[ADI...] have precedence over everything */
102	memcpy(merge, orig_opts, sizeof(*mp) * num_orig);
103	mp = merge + num_orig;
104
105	/* Second, the new options */
106	xt_params->option_offset += XT_OPTION_OFFSET_SCALE;
107	*offset = xt_params->option_offset;
108
109	for (i = 0; i < num_new; ++i, ++mp, ++entry) {
110		mp->name         = entry->name;
111		mp->has_arg      = entry->type != XTTYPE_NONE;
112		mp->flag         = NULL;
113		mp->val          = entry->id + *offset;
114	}
115
116	/* Third, the old options */
117	memcpy(mp, oldopts, sizeof(*mp) * num_old);
118	mp += num_old;
119	xtables_free_opts(0);
120
121	/* Clear trailing entry */
122	memset(mp, 0, sizeof(*mp));
123	return merge;
124}
125
126/**
127 * Give the upper limit for a certain type.
128 */
129static uintmax_t xtopt_max_by_type(enum xt_option_type type)
130{
131	switch (type) {
132	case XTTYPE_UINT8:
133	case XTTYPE_UINT8RC:
134		return UINT8_MAX;
135	case XTTYPE_UINT16:
136	case XTTYPE_UINT16RC:
137		return UINT16_MAX;
138	case XTTYPE_UINT32:
139	case XTTYPE_UINT32RC:
140		return UINT32_MAX;
141	case XTTYPE_UINT64:
142	case XTTYPE_UINT64RC:
143		return UINT64_MAX;
144	default:
145		return 0;
146	}
147}
148
149/**
150 * Return the size of a single entity based upon a type - predominantly an
151 * XTTYPE_UINT*RC type.
152 */
153static size_t xtopt_esize_by_type(enum xt_option_type type)
154{
155	switch (type) {
156	case XTTYPE_UINT8RC:
157		return xtopt_psize[XTTYPE_UINT8];
158	case XTTYPE_UINT16RC:
159		return xtopt_psize[XTTYPE_UINT16];
160	case XTTYPE_UINT32RC:
161		return xtopt_psize[XTTYPE_UINT32];
162	case XTTYPE_UINT64RC:
163		return xtopt_psize[XTTYPE_UINT64];
164	default:
165		return xtopt_psize[type];
166	}
167}
168
169/**
170 * Require a simple integer.
171 */
172static void xtopt_parse_int(struct xt_option_call *cb)
173{
174	const struct xt_option_entry *entry = cb->entry;
175	uintmax_t lmin = 0, lmax = xtopt_max_by_type(entry->type);
176	uintmax_t value;
177
178	if (cb->entry->min != 0)
179		lmin = cb->entry->min;
180	if (cb->entry->max != 0)
181		lmax = cb->entry->max;
182
183	if (!xtables_strtoul(cb->arg, NULL, &value, lmin, lmax))
184		xt_params->exit_err(PARAMETER_PROBLEM,
185			"%s: bad value for option \"--%s\", "
186			"or out of range (%ju-%ju).\n",
187			cb->ext_name, entry->name, lmin, lmax);
188
189	if (entry->type == XTTYPE_UINT8) {
190		cb->val.u8 = value;
191		if (entry->flags & XTOPT_PUT)
192			*(uint8_t *)XTOPT_MKPTR(cb) = cb->val.u8;
193	} else if (entry->type == XTTYPE_UINT16) {
194		cb->val.u16 = value;
195		if (entry->flags & XTOPT_PUT)
196			*(uint16_t *)XTOPT_MKPTR(cb) = cb->val.u16;
197	} else if (entry->type == XTTYPE_UINT32) {
198		cb->val.u32 = value;
199		if (entry->flags & XTOPT_PUT)
200			*(uint32_t *)XTOPT_MKPTR(cb) = cb->val.u32;
201	} else if (entry->type == XTTYPE_UINT64) {
202		cb->val.u64 = value;
203		if (entry->flags & XTOPT_PUT)
204			*(uint64_t *)XTOPT_MKPTR(cb) = cb->val.u64;
205	}
206}
207
208/**
209 * Require a simple floating point number.
210 */
211static void xtopt_parse_float(struct xt_option_call *cb)
212{
213	const struct xt_option_entry *entry = cb->entry;
214	double value;
215	char *end;
216
217	value = strtod(cb->arg, &end);
218	if (end == cb->arg || *end != '\0' ||
219	    (entry->min != entry->max &&
220	    (value < entry->min || value > entry->max)))
221		xt_params->exit_err(PARAMETER_PROBLEM,
222			"%s: bad value for option \"--%s\", "
223			"or out of range (%u-%u).\n",
224			cb->ext_name, entry->name, entry->min, entry->max);
225
226	cb->val.dbl = value;
227	if (entry->flags & XTOPT_PUT)
228		*(double *)XTOPT_MKPTR(cb) = cb->val.dbl;
229}
230
231/**
232 * Copy the parsed value to the appropriate entry in cb->val.
233 */
234static void xtopt_mint_value_to_cb(struct xt_option_call *cb, uintmax_t value)
235{
236	const struct xt_option_entry *entry = cb->entry;
237
238	if (cb->nvals >= ARRAY_SIZE(cb->val.u32_range))
239		return;
240	if (entry->type == XTTYPE_UINT8RC)
241		cb->val.u8_range[cb->nvals] = value;
242	else if (entry->type == XTTYPE_UINT16RC)
243		cb->val.u16_range[cb->nvals] = value;
244	else if (entry->type == XTTYPE_UINT32RC)
245		cb->val.u32_range[cb->nvals] = value;
246	else if (entry->type == XTTYPE_UINT64RC)
247		cb->val.u64_range[cb->nvals] = value;
248}
249
250/**
251 * Copy the parsed value to the data area, using appropriate type access.
252 */
253static void xtopt_mint_value_to_ptr(struct xt_option_call *cb, void **datap,
254				    uintmax_t value)
255{
256	const struct xt_option_entry *entry = cb->entry;
257	void *data = *datap;
258
259	if (!(entry->flags & XTOPT_PUT))
260		return;
261	if (entry->type == XTTYPE_UINT8RC)
262		*(uint8_t *)data = value;
263	else if (entry->type == XTTYPE_UINT16RC)
264		*(uint16_t *)data = value;
265	else if (entry->type == XTTYPE_UINT32RC)
266		*(uint32_t *)data = value;
267	else if (entry->type == XTTYPE_UINT64RC)
268		*(uint64_t *)data = value;
269	data += xtopt_esize_by_type(entry->type);
270	*datap = data;
271}
272
273/**
274 * Multiple integer parse routine.
275 *
276 * This function is capable of parsing any number of fields. Only the first
277 * two values from the string will be put into @cb however (and as such,
278 * @cb->val.uXX_range is just that large) to cater for the few extensions that
279 * do not have a range[2] field, but {min, max}, and which cannot use
280 * XTOPT_POINTER.
281 */
282static void xtopt_parse_mint(struct xt_option_call *cb)
283{
284	const struct xt_option_entry *entry = cb->entry;
285	const char *arg = cb->arg;
286	size_t esize = xtopt_esize_by_type(entry->type);
287	const uintmax_t lmax = xtopt_max_by_type(entry->type);
288	void *put = XTOPT_MKPTR(cb);
289	unsigned int maxiter;
290	uintmax_t value;
291	char *end = "";
292	char sep = ':';
293
294	maxiter = entry->size / esize;
295	if (maxiter == 0)
296		maxiter = ARRAY_SIZE(cb->val.u32_range);
297	if (entry->size % esize != 0)
298		xt_params->exit_err(OTHER_PROBLEM, "%s: memory block does "
299			"not have proper size\n", __func__);
300
301	cb->nvals = 0;
302	for (arg = cb->arg, end = (char *)arg; ; arg = end + 1) {
303		if (cb->nvals == maxiter)
304			xt_params->exit_err(PARAMETER_PROBLEM, "%s: Too many "
305				"components for option \"--%s\" (max: %u)\n",
306				cb->ext_name, entry->name, maxiter);
307		if (*arg == '\0' || *arg == sep) {
308			/* Default range components when field not spec'd. */
309			end = (char *)arg;
310			value = (cb->nvals == 1) ? lmax : 0;
311		} else {
312			if (!xtables_strtoul(arg, &end, &value, 0, lmax))
313				xt_params->exit_err(PARAMETER_PROBLEM,
314					"%s: bad value for option \"--%s\" near "
315					"\"%s\", or out of range (0-%ju).\n",
316					cb->ext_name, entry->name, arg, lmax);
317			if (*end != '\0' && *end != sep)
318				xt_params->exit_err(PARAMETER_PROBLEM,
319					"%s: Argument to \"--%s\" has "
320					"unexpected characters near \"%s\".\n",
321					cb->ext_name, entry->name, end);
322		}
323		xtopt_mint_value_to_cb(cb, value);
324		++cb->nvals;
325		xtopt_mint_value_to_ptr(cb, &put, value);
326		if (*end == '\0')
327			break;
328	}
329}
330
331static void xtopt_parse_string(struct xt_option_call *cb)
332{
333	const struct xt_option_entry *entry = cb->entry;
334	size_t z = strlen(cb->arg);
335	char *p;
336
337	if (entry->min != 0 && z < entry->min)
338		xt_params->exit_err(PARAMETER_PROBLEM,
339			"Argument must have a minimum length of "
340			"%u characters\n", entry->min);
341	if (entry->max != 0 && z > entry->max)
342		xt_params->exit_err(PARAMETER_PROBLEM,
343			"Argument must have a maximum length of "
344			"%u characters\n", entry->max);
345	if (!(entry->flags & XTOPT_PUT))
346		return;
347	if (z >= entry->size)
348		z = entry->size - 1;
349	p = XTOPT_MKPTR(cb);
350	strncpy(p, cb->arg, z);
351	p[z] = '\0';
352}
353
354static const struct tos_symbol_info {
355	unsigned char value;
356	const char *name;
357} tos_symbol_names[] = {
358	{IPTOS_LOWDELAY,    "Minimize-Delay"},
359	{IPTOS_THROUGHPUT,  "Maximize-Throughput"},
360	{IPTOS_RELIABILITY, "Maximize-Reliability"},
361	{IPTOS_MINCOST,     "Minimize-Cost"},
362	{IPTOS_NORMALSVC,   "Normal-Service"},
363	{},
364};
365
366/*
367 * tos_parse_numeric - parse a string like "15/255"
368 *
369 * @str:	input string
370 * @tvm:	(value/mask) tuple
371 * @max:	maximum allowed value (must be pow(2,some_int)-1)
372 */
373static bool tos_parse_numeric(const char *str, struct xt_option_call *cb,
374                              unsigned int max)
375{
376	unsigned int value;
377	char *end;
378
379	xtables_strtoui(str, &end, &value, 0, max);
380	cb->val.tos_value = value;
381	cb->val.tos_mask  = max;
382
383	if (*end == '/') {
384		const char *p = end + 1;
385
386		if (!xtables_strtoui(p, &end, &value, 0, max))
387			xtables_error(PARAMETER_PROBLEM, "Illegal value: \"%s\"",
388			           str);
389		cb->val.tos_mask = value;
390	}
391
392	if (*end != '\0')
393		xtables_error(PARAMETER_PROBLEM, "Illegal value: \"%s\"", str);
394	return true;
395}
396
397/**
398 * @str:	input string
399 * @tvm:	(value/mask) tuple
400 * @def_mask:	mask to force when a symbolic name is used
401 */
402static void xtopt_parse_tosmask(struct xt_option_call *cb)
403{
404	const struct tos_symbol_info *symbol;
405	char *tmp;
406
407	if (xtables_strtoui(cb->arg, &tmp, NULL, 0, UINT8_MAX)) {
408		tos_parse_numeric(cb->arg, cb, UINT8_MAX);
409		return;
410	}
411	/*
412	 * This is our way we deal with different defaults
413	 * for different revisions.
414	 */
415	cb->val.tos_mask = cb->entry->max;
416	for (symbol = tos_symbol_names; symbol->name != NULL; ++symbol)
417		if (strcasecmp(cb->arg, symbol->name) == 0) {
418			cb->val.tos_value = symbol->value;
419			return;
420		}
421
422	xtables_error(PARAMETER_PROBLEM, "Symbolic name \"%s\" is unknown",
423		      cb->arg);
424}
425
426/**
427 * Validate the input for being conformant to "mark[/mask]".
428 */
429static void xtopt_parse_markmask(struct xt_option_call *cb)
430{
431	unsigned int mark = 0, mask = ~0U;
432	char *end;
433
434	if (!xtables_strtoui(cb->arg, &end, &mark, 0, UINT32_MAX))
435		xt_params->exit_err(PARAMETER_PROBLEM,
436			"%s: bad mark value for option \"--%s\", "
437			"or out of range.\n",
438			cb->ext_name, cb->entry->name);
439	if (*end == '/' &&
440	    !xtables_strtoui(end + 1, &end, &mask, 0, UINT32_MAX))
441		xt_params->exit_err(PARAMETER_PROBLEM,
442			"%s: bad mask value for option \"--%s\", "
443			"or out of range.\n",
444			cb->ext_name, cb->entry->name);
445	if (*end != '\0')
446		xt_params->exit_err(PARAMETER_PROBLEM,
447			"%s: trailing garbage after value "
448			"for option \"--%s\".\n",
449			cb->ext_name, cb->entry->name);
450	cb->val.mark = mark;
451	cb->val.mask = mask;
452}
453
454static int xtopt_sysloglvl_compare(const void *a, const void *b)
455{
456	const char *name = a;
457	const struct syslog_level *entry = b;
458
459	return strcmp(name, entry->name);
460}
461
462static void xtopt_parse_sysloglevel(struct xt_option_call *cb)
463{
464	static const struct syslog_level log_names[] = { /* must be sorted */
465		{"alert",   LOG_ALERT},
466		{"crit",    LOG_CRIT},
467		{"debug",   LOG_DEBUG},
468		{"emerg",   LOG_EMERG},
469		{"error",   LOG_ERR}, /* deprecated */
470		{"info",    LOG_INFO},
471		{"notice",  LOG_NOTICE},
472		{"panic",   LOG_EMERG}, /* deprecated */
473		{"warning", LOG_WARNING},
474	};
475	const struct syslog_level *e;
476	unsigned int num = 0;
477
478	if (!xtables_strtoui(cb->arg, NULL, &num, 0, 7)) {
479		e = bsearch(cb->arg, log_names, ARRAY_SIZE(log_names),
480			    sizeof(*log_names), xtopt_sysloglvl_compare);
481		if (e == NULL)
482			xt_params->exit_err(PARAMETER_PROBLEM,
483				"log level \"%s\" unknown\n", cb->arg);
484		num = e->level;
485	}
486	cb->val.syslog_level = num;
487	if (cb->entry->flags & XTOPT_PUT)
488		*(uint8_t *)XTOPT_MKPTR(cb) = num;
489}
490
491static void *xtables_sa_host(const void *sa, unsigned int afproto)
492{
493	if (afproto == AF_INET6)
494		return &((struct sockaddr_in6 *)sa)->sin6_addr;
495	else if (afproto == AF_INET)
496		return &((struct sockaddr_in *)sa)->sin_addr;
497	return (void *)sa;
498}
499
500static socklen_t xtables_sa_hostlen(unsigned int afproto)
501{
502	if (afproto == AF_INET6)
503		return sizeof(struct in6_addr);
504	else if (afproto == AF_INET)
505		return sizeof(struct in_addr);
506	return 0;
507}
508
509/**
510 * Accepts: a hostname (DNS), or a single inetaddr - without any mask. The
511 * result is stored in @cb->val.haddr. Additionally, @cb->val.hmask and
512 * @cb->val.hlen are set for completeness to the appropriate values.
513 */
514static void xtopt_parse_host(struct xt_option_call *cb)
515{
516	struct addrinfo hints = {.ai_family = afinfo->family};
517	unsigned int adcount = 0;
518	struct addrinfo *res, *p;
519	int ret;
520
521	ret = getaddrinfo(cb->arg, NULL, &hints, &res);
522	if (ret < 0)
523		xt_params->exit_err(PARAMETER_PROBLEM,
524			"getaddrinfo: %s\n", gai_strerror(ret));
525
526	memset(&cb->val.hmask, 0xFF, sizeof(cb->val.hmask));
527	cb->val.hlen = (afinfo->family == NFPROTO_IPV4) ? 32 : 128;
528
529	for (p = res; p != NULL; p = p->ai_next) {
530		if (adcount == 0) {
531			memset(&cb->val.haddr, 0, sizeof(cb->val.haddr));
532			memcpy(&cb->val.haddr,
533			       xtables_sa_host(p->ai_addr, p->ai_family),
534			       xtables_sa_hostlen(p->ai_family));
535			++adcount;
536			continue;
537		}
538		if (memcmp(&cb->val.haddr,
539		    xtables_sa_host(p->ai_addr, p->ai_family),
540		    xtables_sa_hostlen(p->ai_family)) != 0)
541			xt_params->exit_err(PARAMETER_PROBLEM,
542				"%s resolves to more than one address\n",
543				cb->arg);
544	}
545
546	freeaddrinfo(res);
547	if (cb->entry->flags & XTOPT_PUT)
548		/* Validation in xtables_option_metavalidate */
549		memcpy(XTOPT_MKPTR(cb), &cb->val.haddr,
550		       sizeof(cb->val.haddr));
551}
552
553/**
554 * @name:	port name, or number as a string (e.g. "http" or "80")
555 *
556 * Resolve a port name to a number. Returns the port number in integral
557 * form on success, or <0 on error. (errno will not be set.)
558 */
559static int xtables_getportbyname(const char *name)
560{
561	struct addrinfo *res = NULL, *p;
562	int ret;
563
564	ret = getaddrinfo(NULL, name, NULL, &res);
565	if (ret < 0)
566		return -1;
567	ret = -1;
568	for (p = res; p != NULL; p = p->ai_next) {
569		if (p->ai_family == AF_INET6) {
570			ret = ((struct sockaddr_in6 *)p->ai_addr)->sin6_port;
571			break;
572		} else if (p->ai_family == AF_INET) {
573			ret = ((struct sockaddr_in *)p->ai_addr)->sin_port;
574			break;
575		}
576	}
577	freeaddrinfo(res);
578	if (ret < 0)
579		return ret;
580	return ntohs(ret);
581}
582
583/**
584 * Validate and parse a protocol specification (number or name) by use of
585 * /etc/protocols and put the result into @cb->val.protocol.
586 */
587static void xtopt_parse_protocol(struct xt_option_call *cb)
588{
589	cb->val.protocol = xtables_parse_protocol(cb->arg);
590	if (cb->entry->flags & XTOPT_PUT)
591		*(uint8_t *)XTOPT_MKPTR(cb) = cb->val.protocol;
592}
593
594/**
595 * Validate and parse a port specification and put the result into
596 * @cb->val.port.
597 */
598static void xtopt_parse_port(struct xt_option_call *cb)
599{
600	const struct xt_option_entry *entry = cb->entry;
601	int ret;
602
603	ret = xtables_getportbyname(cb->arg);
604	if (ret < 0)
605		xt_params->exit_err(PARAMETER_PROBLEM,
606			"Port \"%s\" does not resolve to anything.\n",
607			cb->arg);
608	if (entry->flags & XTOPT_NBO)
609		ret = htons(ret);
610	cb->val.port = ret;
611	if (entry->flags & XTOPT_PUT)
612		*(uint16_t *)XTOPT_MKPTR(cb) = cb->val.port;
613}
614
615static void xtopt_parse_mport(struct xt_option_call *cb)
616{
617	static const size_t esize = sizeof(uint16_t);
618	const struct xt_option_entry *entry = cb->entry;
619	char *lo_arg, *wp_arg, *arg;
620	unsigned int maxiter;
621	int value;
622
623	wp_arg = lo_arg = strdup(cb->arg);
624	if (lo_arg == NULL)
625		xt_params->exit_err(RESOURCE_PROBLEM, "strdup");
626
627	maxiter = entry->size / esize;
628	if (maxiter == 0)
629		maxiter = 2; /* ARRAY_SIZE(cb->val.port_range) */
630	if (entry->size % esize != 0)
631		xt_params->exit_err(OTHER_PROBLEM, "%s: memory block does "
632			"not have proper size\n", __func__);
633
634	cb->val.port_range[0] = 0;
635	cb->val.port_range[1] = UINT16_MAX;
636	cb->nvals = 0;
637
638	while ((arg = strsep(&wp_arg, ":")) != NULL) {
639		if (cb->nvals == maxiter)
640			xt_params->exit_err(PARAMETER_PROBLEM, "%s: Too many "
641				"components for option \"--%s\" (max: %u)\n",
642				cb->ext_name, entry->name, maxiter);
643		if (*arg == '\0') {
644			++cb->nvals;
645			continue;
646		}
647
648		value = xtables_getportbyname(arg);
649		if (value < 0)
650			xt_params->exit_err(PARAMETER_PROBLEM,
651				"Port \"%s\" does not resolve to "
652				"anything.\n", arg);
653		if (entry->flags & XTOPT_NBO)
654			value = htons(value);
655		if (cb->nvals < ARRAY_SIZE(cb->val.port_range))
656			cb->val.port_range[cb->nvals] = value;
657		++cb->nvals;
658	}
659
660	if (cb->nvals == 1) {
661		cb->val.port_range[1] = cb->val.port_range[0];
662		++cb->nvals;
663	}
664	if (entry->flags & XTOPT_PUT)
665		memcpy(XTOPT_MKPTR(cb), cb->val.port_range, sizeof(uint16_t) *
666		       (cb->nvals <= maxiter ? cb->nvals : maxiter));
667	free(lo_arg);
668}
669
670static int xtopt_parse_mask(struct xt_option_call *cb)
671{
672	struct addrinfo hints = {.ai_family = afinfo->family,
673				 .ai_flags = AI_NUMERICHOST };
674	struct addrinfo *res;
675	int ret;
676
677	ret = getaddrinfo(cb->arg, NULL, &hints, &res);
678	if (ret < 0)
679		return 0;
680
681	memcpy(&cb->val.hmask, xtables_sa_host(res->ai_addr, res->ai_family),
682	       xtables_sa_hostlen(res->ai_family));
683
684	switch(afinfo->family) {
685	case AF_INET:
686		cb->val.hlen = xtables_ipmask_to_cidr(&cb->val.hmask.in);
687		break;
688	case AF_INET6:
689		cb->val.hlen = xtables_ip6mask_to_cidr(&cb->val.hmask.in6);
690		break;
691	}
692
693	freeaddrinfo(res);
694	return 1;
695}
696
697/**
698 * Parse an integer and ensure it is within the address family's prefix length
699 * limits. The result is stored in @cb->val.hlen.
700 */
701static void xtopt_parse_plen(struct xt_option_call *cb)
702{
703	const struct xt_option_entry *entry = cb->entry;
704	unsigned int prefix_len = 128; /* happiness is a warm gcc */
705
706	cb->val.hlen = (afinfo->family == NFPROTO_IPV4) ? 32 : 128;
707	if (!xtables_strtoui(cb->arg, NULL, &prefix_len, 0, cb->val.hlen)) {
708		/* Is this mask expressed in full format? e.g. 255.255.255.0 */
709		if (xtopt_parse_mask(cb))
710			return;
711
712		xt_params->exit_err(PARAMETER_PROBLEM,
713			"%s: bad value for option \"--%s\", "
714			"neither a valid network mask "
715			"nor valid CIDR (%u-%u).\n",
716			cb->ext_name, entry->name, 0, cb->val.hlen);
717	}
718	cb->val.hlen = prefix_len;
719}
720
721/**
722 * Reuse xtopt_parse_plen for testing the integer. Afterwards convert this to
723 * a bitmask, and make it available through @cb->val.hmask (hlen remains
724 * valid). If %XTOPT_PUT is used, hmask will be copied to the target area.
725 */
726static void xtopt_parse_plenmask(struct xt_option_call *cb)
727{
728	const struct xt_option_entry *entry = cb->entry;
729	uint32_t *mask = cb->val.hmask.all;
730
731	xtopt_parse_plen(cb);
732
733	memset(mask, 0xFF, sizeof(union nf_inet_addr));
734	/* This shifting is AF-independent. */
735	if (cb->val.hlen == 0) {
736		mask[0] = mask[1] = mask[2] = mask[3] = 0;
737	} else if (cb->val.hlen <= 32) {
738		mask[0] <<= 32 - cb->val.hlen;
739		mask[1] = mask[2] = mask[3] = 0;
740	} else if (cb->val.hlen <= 64) {
741		mask[1] <<= 32 - (cb->val.hlen - 32);
742		mask[2] = mask[3] = 0;
743	} else if (cb->val.hlen <= 96) {
744		mask[2] <<= 32 - (cb->val.hlen - 64);
745		mask[3] = 0;
746	} else if (cb->val.hlen <= 128) {
747		mask[3] <<= 32 - (cb->val.hlen - 96);
748	}
749	mask[0] = htonl(mask[0]);
750	mask[1] = htonl(mask[1]);
751	mask[2] = htonl(mask[2]);
752	mask[3] = htonl(mask[3]);
753	if (entry->flags & XTOPT_PUT)
754		memcpy(XTOPT_MKPTR(cb), mask, sizeof(union nf_inet_addr));
755}
756
757static void xtopt_parse_hostmask(struct xt_option_call *cb)
758{
759	const char *orig_arg = cb->arg;
760	char *work, *p;
761
762	if (strchr(cb->arg, '/') == NULL) {
763		xtopt_parse_host(cb);
764		return;
765	}
766	work = strdup(orig_arg);
767	if (work == NULL)
768		xt_params->exit_err(PARAMETER_PROBLEM, "strdup");
769	p = strchr(work, '/'); /* by def this can't be NULL now */
770	*p++ = '\0';
771	/*
772	 * Because xtopt_parse_host and xtopt_parse_plenmask would store
773	 * different things in the same target area, XTTYPE_HOSTMASK must
774	 * disallow XTOPT_PUT, which it does by forcing its absence,
775	 * cf. not being listed in xtopt_psize.
776	 */
777	cb->arg = work;
778	xtopt_parse_host(cb);
779	cb->arg = p;
780	xtopt_parse_plenmask(cb);
781	cb->arg = orig_arg;
782}
783
784static void xtopt_parse_ethermac(struct xt_option_call *cb)
785{
786	const char *arg = cb->arg;
787	unsigned int i;
788	char *end;
789
790	for (i = 0; i < ARRAY_SIZE(cb->val.ethermac) - 1; ++i) {
791		cb->val.ethermac[i] = strtoul(arg, &end, 16);
792		if (*end != ':' || end - arg > 2)
793			goto out;
794		arg = end + 1;
795	}
796	i = ARRAY_SIZE(cb->val.ethermac) - 1;
797	cb->val.ethermac[i] = strtoul(arg, &end, 16);
798	if (*end != '\0' || end - arg > 2)
799		goto out;
800	if (cb->entry->flags & XTOPT_PUT)
801		memcpy(XTOPT_MKPTR(cb), cb->val.ethermac,
802		       sizeof(cb->val.ethermac));
803	return;
804 out:
805	xt_params->exit_err(PARAMETER_PROBLEM, "ether");
806}
807
808static void (*const xtopt_subparse[])(struct xt_option_call *) = {
809	[XTTYPE_UINT8]       = xtopt_parse_int,
810	[XTTYPE_UINT16]      = xtopt_parse_int,
811	[XTTYPE_UINT32]      = xtopt_parse_int,
812	[XTTYPE_UINT64]      = xtopt_parse_int,
813	[XTTYPE_UINT8RC]     = xtopt_parse_mint,
814	[XTTYPE_UINT16RC]    = xtopt_parse_mint,
815	[XTTYPE_UINT32RC]    = xtopt_parse_mint,
816	[XTTYPE_UINT64RC]    = xtopt_parse_mint,
817	[XTTYPE_DOUBLE]      = xtopt_parse_float,
818	[XTTYPE_STRING]      = xtopt_parse_string,
819	[XTTYPE_TOSMASK]     = xtopt_parse_tosmask,
820	[XTTYPE_MARKMASK32]  = xtopt_parse_markmask,
821	[XTTYPE_SYSLOGLEVEL] = xtopt_parse_sysloglevel,
822	[XTTYPE_HOST]        = xtopt_parse_host,
823	[XTTYPE_HOSTMASK]    = xtopt_parse_hostmask,
824	[XTTYPE_PROTOCOL]    = xtopt_parse_protocol,
825	[XTTYPE_PORT]        = xtopt_parse_port,
826	[XTTYPE_PORTRC]      = xtopt_parse_mport,
827	[XTTYPE_PLEN]        = xtopt_parse_plen,
828	[XTTYPE_PLENMASK]    = xtopt_parse_plenmask,
829	[XTTYPE_ETHERMAC]    = xtopt_parse_ethermac,
830};
831
832/**
833 * The master option parsing routine. May be used for the ".x6_parse"
834 * function pointer in extensions if fully automatic parsing is desired.
835 * It may be also called manually from a custom x6_parse function.
836 */
837void xtables_option_parse(struct xt_option_call *cb)
838{
839	const struct xt_option_entry *entry = cb->entry;
840	unsigned int eflag = 1 << cb->entry->id;
841
842	/*
843	 * With {.id = P_FOO, .excl = P_FOO} we can have simple double-use
844	 * prevention. Though it turned out that this is too much typing (most
845	 * of the options are one-time use only), so now we also have
846	 * %XTOPT_MULTI.
847	 */
848	if ((!(entry->flags & XTOPT_MULTI) || (entry->excl & eflag)) &&
849	    cb->xflags & eflag)
850		xt_params->exit_err(PARAMETER_PROBLEM,
851			"%s: option \"--%s\" can only be used once.\n",
852			cb->ext_name, cb->entry->name);
853	if (cb->invert && !(entry->flags & XTOPT_INVERT))
854		xt_params->exit_err(PARAMETER_PROBLEM,
855			"%s: option \"--%s\" cannot be inverted.\n",
856			cb->ext_name, entry->name);
857	if (entry->type != XTTYPE_NONE && optarg == NULL)
858		xt_params->exit_err(PARAMETER_PROBLEM,
859			"%s: option \"--%s\" requires an argument.\n",
860			cb->ext_name, entry->name);
861	/*
862	 * Fill in fallback value for "nvals", in case an extension (as it
863	 * happened with libxt_conntrack.2) tries to read it, despite not using
864	 * a *RC option type.
865	 */
866	cb->nvals = 1;
867	if (entry->type <= ARRAY_SIZE(xtopt_subparse) &&
868	    xtopt_subparse[entry->type] != NULL)
869		xtopt_subparse[entry->type](cb);
870	/* Exclusion with other flags tested later in finalize. */
871	cb->xflags |= 1 << entry->id;
872}
873
874/**
875 * Verifies that an extension's option map descriptor is valid, and ought to
876 * be called right after the extension has been loaded, and before option
877 * merging/xfrm.
878 */
879void xtables_option_metavalidate(const char *name,
880				 const struct xt_option_entry *entry)
881{
882	for (; entry->name != NULL; ++entry) {
883		if (entry->id >= CHAR_BIT * sizeof(unsigned int) ||
884		    entry->id >= XT_OPTION_OFFSET_SCALE)
885			xt_params->exit_err(OTHER_PROBLEM,
886				"Extension %s uses invalid ID %u\n",
887				name, entry->id);
888		if (!(entry->flags & XTOPT_PUT)) {
889			if (entry->ptroff != 0)
890				xt_params->exit_err(OTHER_PROBLEM,
891					"%s: ptroff for \"--%s\" is non-"
892					"zero but no XTOPT_PUT is specified. "
893					"Oversight?", name, entry->name);
894			continue;
895		}
896		if (entry->type >= ARRAY_SIZE(xtopt_psize) ||
897		    xtopt_psize[entry->type] == 0)
898			xt_params->exit_err(OTHER_PROBLEM,
899				"%s: entry type of option \"--%s\" cannot be "
900				"combined with XTOPT_PUT\n",
901				name, entry->name);
902		if (xtopt_psize[entry->type] != -1 &&
903		    xtopt_psize[entry->type] != entry->size)
904			xt_params->exit_err(OTHER_PROBLEM,
905				"%s: option \"--%s\" points to a memory block "
906				"of wrong size (expected %zu, got %zu)\n",
907				name, entry->name,
908				xtopt_psize[entry->type], entry->size);
909	}
910}
911
912/**
913 * Find an option entry by its id.
914 */
915static const struct xt_option_entry *
916xtables_option_lookup(const struct xt_option_entry *entry, unsigned int id)
917{
918	for (; entry->name != NULL; ++entry)
919		if (entry->id == id)
920			return entry;
921	return NULL;
922}
923
924/**
925 * @c:		getopt id (i.e. with offset)
926 * @fw:		struct ipt_entry or ip6t_entry
927 *
928 * Dispatch arguments to the appropriate parse function, based upon the
929 * extension's choice of API.
930 */
931void xtables_option_tpcall(unsigned int c, char **argv, bool invert,
932			   struct xtables_target *t, void *fw)
933{
934	struct xt_option_call cb;
935
936	if (t->x6_parse == NULL) {
937		if (t->parse != NULL)
938			t->parse(c - t->option_offset, argv, invert,
939				 &t->tflags, fw, &t->t);
940		return;
941	}
942
943	c -= t->option_offset;
944	cb.entry = xtables_option_lookup(t->x6_options, c);
945	if (cb.entry == NULL)
946		xtables_error(OTHER_PROBLEM,
947			"Extension does not know id %u\n", c);
948	cb.arg      = optarg;
949	cb.invert   = invert;
950	cb.ext_name = t->name;
951	cb.data     = t->t->data;
952	cb.xflags   = t->tflags;
953	cb.target   = &t->t;
954	cb.xt_entry = fw;
955	cb.udata    = t->udata;
956	t->x6_parse(&cb);
957	t->tflags = cb.xflags;
958}
959
960/**
961 * @c:		getopt id (i.e. with offset)
962 * @fw:		struct ipt_entry or ip6t_entry
963 *
964 * Dispatch arguments to the appropriate parse function, based upon the
965 * extension's choice of API.
966 */
967void xtables_option_mpcall(unsigned int c, char **argv, bool invert,
968			   struct xtables_match *m, void *fw)
969{
970	struct xt_option_call cb;
971
972	if (m->x6_parse == NULL) {
973		if (m->parse != NULL)
974			m->parse(c - m->option_offset, argv, invert,
975				 &m->mflags, fw, &m->m);
976		return;
977	}
978
979	c -= m->option_offset;
980	cb.entry = xtables_option_lookup(m->x6_options, c);
981	if (cb.entry == NULL)
982		xtables_error(OTHER_PROBLEM,
983			"Extension does not know id %u\n", c);
984	cb.arg      = optarg;
985	cb.invert   = invert;
986	cb.ext_name = m->name;
987	cb.data     = m->m->data;
988	cb.xflags   = m->mflags;
989	cb.match    = &m->m;
990	cb.xt_entry = fw;
991	cb.udata    = m->udata;
992	m->x6_parse(&cb);
993	m->mflags = cb.xflags;
994}
995
996/**
997 * @name:	name of extension
998 * @entry:	current option (from all ext's entries) being validated
999 * @xflags:	flags the extension has collected
1000 * @i:		conflicting option (id) to test for
1001 */
1002static void
1003xtables_option_fcheck2(const char *name, const struct xt_option_entry *entry,
1004		       const struct xt_option_entry *other,
1005		       unsigned int xflags)
1006{
1007	unsigned int ef = 1 << entry->id, of = 1 << other->id;
1008
1009	if (entry->also & of && !(xflags & of))
1010		xt_params->exit_err(PARAMETER_PROBLEM,
1011			"%s: option \"--%s\" also requires \"--%s\".\n",
1012			name, entry->name, other->name);
1013
1014	if (!(entry->excl & of))
1015		/* Use of entry does not collide with other option, good. */
1016		return;
1017	if ((xflags & (ef | of)) != (ef | of))
1018		/* Conflicting options were not used. */
1019		return;
1020
1021	xt_params->exit_err(PARAMETER_PROBLEM,
1022		"%s: option \"--%s\" cannot be used together with \"--%s\".\n",
1023		name, entry->name, other->name);
1024}
1025
1026/**
1027 * @name:	name of extension
1028 * @xflags:	accumulated flags
1029 * @entry:	extension's option table
1030 *
1031 * Check that all option constraints have been met. This effectively replaces
1032 * ->final_check of the older API.
1033 */
1034void xtables_options_fcheck(const char *name, unsigned int xflags,
1035			    const struct xt_option_entry *table)
1036{
1037	const struct xt_option_entry *entry, *other;
1038	unsigned int i;
1039
1040	for (entry = table; entry->name != NULL; ++entry) {
1041		if (entry->flags & XTOPT_MAND &&
1042		    !(xflags & (1 << entry->id)))
1043			xt_params->exit_err(PARAMETER_PROBLEM,
1044				"%s: option \"--%s\" must be specified\n",
1045				name, entry->name);
1046		if (!(xflags & (1 << entry->id)))
1047			/* Not required, not specified, thus skip. */
1048			continue;
1049
1050		for (i = 0; i < CHAR_BIT * sizeof(entry->id); ++i) {
1051			if (entry->id == i)
1052				/*
1053				 * Avoid conflict with self. Multi-use check
1054				 * was done earlier in xtables_option_parse.
1055				 */
1056				continue;
1057			other = xtables_option_lookup(table, i);
1058			if (other == NULL)
1059				continue;
1060			xtables_option_fcheck2(name, entry, other, xflags);
1061		}
1062	}
1063}
1064
1065/**
1066 * Dispatch arguments to the appropriate final_check function, based upon the
1067 * extension's choice of API.
1068 */
1069void xtables_option_tfcall(struct xtables_target *t)
1070{
1071	if (t->x6_fcheck != NULL) {
1072		struct xt_fcheck_call cb;
1073
1074		cb.ext_name = t->name;
1075		cb.data     = t->t->data;
1076		cb.xflags   = t->tflags;
1077		cb.udata    = t->udata;
1078		t->x6_fcheck(&cb);
1079	} else if (t->final_check != NULL) {
1080		t->final_check(t->tflags);
1081	}
1082	if (t->x6_options != NULL)
1083		xtables_options_fcheck(t->name, t->tflags, t->x6_options);
1084}
1085
1086/**
1087 * Dispatch arguments to the appropriate final_check function, based upon the
1088 * extension's choice of API.
1089 */
1090void xtables_option_mfcall(struct xtables_match *m)
1091{
1092	if (m->x6_fcheck != NULL) {
1093		struct xt_fcheck_call cb;
1094
1095		cb.ext_name = m->name;
1096		cb.data     = m->m->data;
1097		cb.xflags   = m->mflags;
1098		cb.udata    = m->udata;
1099		m->x6_fcheck(&cb);
1100	} else if (m->final_check != NULL) {
1101		m->final_check(m->mflags);
1102	}
1103	if (m->x6_options != NULL)
1104		xtables_options_fcheck(m->name, m->mflags, m->x6_options);
1105}
1106
1107struct xtables_lmap *xtables_lmap_init(const char *file)
1108{
1109	struct xtables_lmap *lmap_head = NULL, *lmap_prev = NULL, *lmap_this;
1110	char buf[512];
1111	FILE *fp;
1112	char *cur, *nxt;
1113	int id;
1114
1115	fp = fopen(file, "re");
1116	if (fp == NULL)
1117		return NULL;
1118
1119	while (fgets(buf, sizeof(buf), fp) != NULL) {
1120		cur = buf;
1121		while (isspace(*cur))
1122			++cur;
1123		if (*cur == '#' || *cur == '\n' || *cur == '\0')
1124			continue;
1125
1126		/* iproute2 allows hex and dec format */
1127		errno = 0;
1128		id = strtoul(cur, &nxt, strncmp(cur, "0x", 2) == 0 ? 16 : 10);
1129		if (nxt == cur || errno != 0)
1130			continue;
1131
1132		/* same boundaries as in iproute2 */
1133		if (id < 0 || id > 255)
1134			continue;
1135		cur = nxt;
1136
1137		if (!isspace(*cur))
1138			continue;
1139		while (isspace(*cur))
1140			++cur;
1141		if (*cur == '#' || *cur == '\n' || *cur == '\0')
1142			continue;
1143		nxt = cur;
1144		while (*nxt != '\0' && !isspace(*nxt))
1145			++nxt;
1146		if (nxt == cur)
1147			continue;
1148		*nxt = '\0';
1149
1150		/* found valid data */
1151		lmap_this = malloc(sizeof(*lmap_this));
1152		if (lmap_this == NULL) {
1153			perror("malloc");
1154			goto out;
1155		}
1156		lmap_this->id   = id;
1157		lmap_this->name = strdup(cur);
1158		if (lmap_this->name == NULL) {
1159			free(lmap_this);
1160			goto out;
1161		}
1162		lmap_this->next = NULL;
1163
1164		if (lmap_prev != NULL)
1165			lmap_prev->next = lmap_this;
1166		else
1167			lmap_head = lmap_this;
1168		lmap_prev = lmap_this;
1169	}
1170
1171	fclose(fp);
1172	return lmap_head;
1173 out:
1174	fclose(fp);
1175	xtables_lmap_free(lmap_head);
1176	return NULL;
1177}
1178
1179void xtables_lmap_free(struct xtables_lmap *head)
1180{
1181	struct xtables_lmap *next;
1182
1183	for (; head != NULL; head = next) {
1184		next = head->next;
1185		free(head->name);
1186		free(head);
1187	}
1188}
1189
1190int xtables_lmap_name2id(const struct xtables_lmap *head, const char *name)
1191{
1192	for (; head != NULL; head = head->next)
1193		if (strcmp(head->name, name) == 0)
1194			return head->id;
1195	return -1;
1196}
1197
1198const char *xtables_lmap_id2name(const struct xtables_lmap *head, int id)
1199{
1200	for (; head != NULL; head = head->next)
1201		if (head->id == id)
1202			return head->name;
1203	return NULL;
1204}
1205