conffile.c revision 1.8 
1/* $NetBSD: conffile.c,v 1.8 2013/10/18 14:14:14 kefren Exp $ */
2
3/*
4 * Copyright (c) 2010 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Mihai Chelaru <kefren@NetBSD.org>
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32#include <arpa/inet.h>
33#include <netinet/in.h>
34#include <sys/mman.h>
35#include <ctype.h>
36#include <fcntl.h>
37#include <stdlib.h>
38#include <string.h>
39#include <unistd.h>
40
41#include "conffile.h"
42#include "ldp_errors.h"
43
44#define NextCommand(x) strsep(&x, " ")
45#define LINEMAXSIZE 1024
46
47char *mapped, *nextline;
48size_t mapsize;
49
50extern int ldp_hello_time, ldp_keepalive_time, ldp_holddown_time, command_port,
51	min_label, max_label, no_default_route, loop_detection;
52struct in_addr conf_ldp_id;
53
54static int conf_dispatch(char*);
55static char * conf_getlinelimit(void);
56static int checkeol(char*);
57static int Fhellotime(char*);
58static int Fport(char*);
59static int Fholddown(char*);
60static int Fkeepalive(char*);
61static int Fmaxlabel(char*);
62static int Fminlabel(char*);
63static int Fldpid(char*);
64static int Fneighbour(char*);
65static int Gneighbour(struct conf_neighbour *, char *);
66static int Fnodefault(char*);
67static int Floopdetection(char*);
68static int Finterface(char*);
69static int Ginterface(struct conf_interface *, char *);
70static int Ipassive(struct conf_interface *, char *);
71static int Itaddr(struct conf_interface *, char *);
72
73struct conf_func {
74	char com[64];
75	int (* func)(char *);
76};
77
78struct intf_func {
79	char com[64];
80	int (* func)(struct conf_interface *, char *);
81};
82
83struct conf_func main_commands[] = {
84	{ "hello-time", Fhellotime },
85	{ "keepalive-time", Fkeepalive },
86	{ "holddown-time", Fholddown },
87	{ "command-port", Fport },
88	{ "min-label", Fminlabel },
89	{ "max-label", Fmaxlabel },
90	{ "ldp-id", Fldpid },
91	{ "neighbor", Fneighbour },
92	{ "neighbour", Fneighbour },
93	{ "no-default-route", Fnodefault },
94	{ "loop-detection", Floopdetection },
95	{ "interface", Finterface },
96	{ "", NULL },
97};
98
99struct intf_func intf_commands[] = {
100	{ "passive", Ipassive },
101	{ "transport-address", Itaddr },
102	{ "", NULL },
103};
104
105static int parseline;
106
107/*
108 * Parses config file
109 */
110int
111conf_parsefile(const char *fname)
112{
113	char line[LINEMAXSIZE+1];
114	struct stat fs;
115
116	SLIST_INIT(&conei_head);
117	SLIST_INIT(&coifs_head);
118	conf_ldp_id.s_addr = 0;
119
120	int confh = open(fname, O_RDONLY, 0);
121
122	if (confh == -1 || fstat(confh, &fs) == -1 ||
123	    (mapped = mmap(NULL, fs.st_size, PROT_READ, MAP_SHARED, confh, 0))
124	    == MAP_FAILED)
125		return E_CONF_IO;
126
127	mapsize = fs.st_size;
128	nextline = mapped;
129	for (parseline = 1; ; parseline++) {
130		char *prev = nextline;
131		if ((nextline = conf_getlinelimit()) == NULL)
132			break;
133		while (isspace((int)*prev) != 0 && prev < nextline)
134			prev++;
135		if (nextline - prev < 2)
136			continue;
137		else if (nextline - prev > LINEMAXSIZE)
138			goto parerr;
139		memcpy(line, prev, nextline - prev);
140		if (line[0] == '#')
141			continue;
142		else
143			line[nextline - prev] = '\0';
144		if (conf_dispatch(line) != 0)
145			goto parerr;
146	}
147	munmap(mapped, mapsize);
148	close(confh);
149	return 0;
150parerr:
151	munmap(mapped, mapsize);
152	close(confh);
153	return parseline;
154}
155
156char *
157conf_getlinelimit(void)
158{
159	char *p = nextline;
160
161	if (nextline < mapped || (size_t)(nextline - mapped) >= mapsize)
162		return NULL;
163
164	for (p = nextline; *p != '\n' && (size_t)(p - mapped) < mapsize; p++);
165	return p + 1;
166}
167
168/*
169 * Looks for a matching command on a line
170 */
171int
172conf_dispatch(char *line)
173{
174	int i, last_match = -1, matched = 0;
175	char *command, *nline = line;
176
177	if (strlen(line) == 0 || line[0] == '#')
178		return E_CONF_OK;
179	command = NextCommand(nline);
180	for (i = 0; main_commands[i].func != NULL; i++)
181		if (strncasecmp(main_commands[i].com, command,
182		    strlen(main_commands[i].com)) == 0) {
183			matched++;
184			last_match = i;
185		}
186	if (matched == 0)
187		return E_CONF_NOMATCH;
188	else if (matched > 1)
189		return E_CONF_AMBIGUOUS;
190
191	if (nline == NULL || checkeol(nline) != 0)
192		return E_CONF_PARAM;
193	return main_commands[last_match].func(nline);
194}
195
196/*
197 * Checks if a line is terminated or else if it contains
198 * a start block bracket. If it's semicolon terminated
199 * then trim it.
200 */
201int
202checkeol(char *line)
203{
204	size_t len = strlen(line);
205	if (len > 0 && line[len - 1] == '\n') {
206		line[len - 1] = '\0';
207		len--;
208	}
209	if (len > 0 && line[len - 1] == ';') {
210		line[len - 1] = '\0';
211		return 0;
212	}
213	for (size_t i = 0; i < len; i++)
214		if (line[i] == '{')
215			return 0;
216	return -1;
217}
218
219/*
220 * Sets hello time
221 */
222int
223Fhellotime(char *line)
224{
225	int ht = atoi(line);
226	if (ht <= 0)
227		return E_CONF_PARAM;
228	ldp_hello_time = ht;
229	return 0;
230}
231
232/*
233 * Sets command port
234 */
235int
236Fport(char *line)
237{
238	int cp = atoi(line);
239	if (cp <= 0 || cp > 65535)
240		return E_CONF_PARAM;
241	command_port = cp;
242	return 0;
243}
244
245/*
246 * Sets neighbour keepalive
247 */
248int
249Fkeepalive(char *line)
250{
251	int kt = atoi(line);
252	if (kt <= 0)
253		return E_CONF_PARAM;
254	ldp_keepalive_time = kt;
255	return 0;
256}
257
258/*
259 * Sets neighbour holddown timer
260 */
261int
262Fholddown(char *line)
263{
264	int hdt = atoi(line);
265	if (hdt <= 0)
266		return E_CONF_PARAM;
267	ldp_holddown_time = hdt;
268	return 0;
269}
270
271int
272Fminlabel(char *line)
273{
274	int ml = atoi(line);
275	if (ml <= 0)
276		return E_CONF_PARAM;
277	min_label = ml;
278	return 0;
279}
280
281int
282Fmaxlabel(char *line)
283{
284	int ml = atoi(line);
285	if (ml <= 0)
286		return E_CONF_PARAM;
287	max_label = ml;
288	return 0;
289}
290
291int
292Fldpid(char *line)
293{
294	if (inet_pton(AF_INET, line, &conf_ldp_id) != 1)
295		return E_CONF_PARAM;
296	return 0;
297}
298
299int
300Fneighbour(char *line)
301{
302	char *peer;
303	struct conf_neighbour *nei;
304	struct in_addr ad;
305	char buf[LINEMAXSIZE];
306
307	peer = NextCommand(line);
308	if (inet_pton(AF_INET, peer, &ad) != 1)
309		return E_CONF_PARAM;
310
311	nei = calloc(1, sizeof(*nei));
312	if (nei == NULL)
313		return E_CONF_MEM;
314	nei->address.s_addr = ad.s_addr;
315	SLIST_INSERT_HEAD(&conei_head, nei, neilist);
316
317	for ( ; ; ) {
318		char *prev = nextline;
319		parseline++;
320		nextline = conf_getlinelimit();
321		if (nextline == NULL || (size_t)(nextline - prev) > LINEMAXSIZE)
322			return -1;
323		while (isspace((int)*prev) != 0 && prev < nextline)
324			prev++;
325		memcpy(buf, prev, nextline - prev);
326		if (nextline - prev < 2 || buf[0] == '#')
327			continue;
328		else if (buf[0] == '}')
329			break;
330		else
331			buf[nextline - prev] = '\0';
332		if (Gneighbour(nei, buf) == -1)
333			return -1;
334	}
335	return -1;
336}
337
338/*
339 * neighbour { } sub-commands
340 */
341int
342Gneighbour(struct conf_neighbour *nei, char *line)
343{
344	if (strncasecmp("authenticate", line, 12) == 0) {
345		nei->authenticate = 1;
346		return 0;
347	}
348	return -1;
349}
350
351int
352Fnodefault(char *line)
353{
354	int nd = atoi(line);
355	if (nd < 0)
356		return E_CONF_PARAM;
357	no_default_route = nd;
358	return 0;
359}
360
361int
362Floopdetection(char *line)
363{
364	int loopd = atoi(line);
365	if (loopd < 0)
366		return E_CONF_PARAM;
367	loop_detection = loopd;
368	return 0;
369}
370
371/*
372 * Interface sub-commands
373 */
374int
375Finterface(char *line)
376{
377	char *ifname;
378	struct conf_interface *conf_if = calloc(1, sizeof(*conf_if));
379	char buf[LINEMAXSIZE];
380
381	ifname = NextCommand(line);
382	if (conf_if == NULL || ifname == NULL)
383		return -1;
384	strlcpy(conf_if->if_name, ifname, IF_NAMESIZE);
385	SLIST_INSERT_HEAD(&coifs_head, conf_if, iflist);
386
387	for ( ; ; ) {
388		char *prev = nextline;
389		parseline++;
390		nextline = conf_getlinelimit();
391		if (nextline == NULL || (size_t)(nextline - prev) > LINEMAXSIZE)
392			return -1;
393		while (isspace((int)*prev) != 0 && prev < nextline)
394			prev++;
395		memcpy(buf, prev, nextline - prev);
396		if (nextline - prev < 2 || buf[0] == '#')
397			continue;
398		else if (buf[0] == '}')
399			break;
400		else
401			buf[nextline - prev] = '\0';
402		if (Ginterface(conf_if, buf) == -1)
403			return -1;
404	}
405	return 0;
406}
407
408int
409Ginterface(struct conf_interface *conf_if, char *buf)
410{
411	int i;
412
413	for (i = 0; intf_commands[i].func != NULL; i++)
414		if (strncasecmp(buf, intf_commands[i].com,
415		    strlen(intf_commands[i].com)) == 0)
416			return intf_commands[i].func(conf_if, buf +
417			    strlen(intf_commands[i].com) + 1);
418	/* command not found */
419	return -1;
420}
421
422/* sets transport address */
423int
424Itaddr(struct conf_interface *conf_if, char *buf)
425{
426	if (inet_pton(AF_INET, buf, &conf_if->tr_addr) != 1)
427		return -1;
428	return 0;
429}
430
431/* sets passive-interface on */
432int
433Ipassive(struct conf_interface *conf_if, char *buf)
434{
435	conf_if->passive = 1;
436	return 0;
437}
438