xref: /openbsd-src/lib/libpcap/nametoaddr.c (revision 4e1ee0786f11cc571bd0be17d38e46f635c719fc)
1 /*	$OpenBSD: nametoaddr.c,v 1.23 2021/09/10 00:01:13 deraadt Exp $	*/
2 
3 /*
4  * Copyright (c) 1990, 1991, 1992, 1993, 1994, 1995, 1996
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that: (1) source code distributions
9  * retain the above copyright notice and this paragraph in its entirety, (2)
10  * distributions including binary code include the above copyright notice and
11  * this paragraph in its entirety in the documentation or other materials
12  * provided with the distribution, and (3) all advertising materials mentioning
13  * features or use of this software display the following acknowledgement:
14  * ``This product includes software developed by the University of California,
15  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
16  * the University nor the names of its contributors may be used to endorse
17  * or promote products derived from this software without specific prior
18  * written permission.
19  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
20  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
21  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
22  *
23  * Name to id translation routines used by the scanner.
24  * These functions are not time critical.
25  */
26 
27 #include <sys/types.h>				/* concession to AIX */
28 #include <sys/socket.h>
29 #include <sys/time.h>
30 
31 struct mbuf;
32 struct rtentry;
33 
34 #include <net/if.h>
35 #include <netinet/in.h>
36 #include <netinet/if_ether.h>
37 #include <arpa/inet.h>
38 
39 #include <ctype.h>
40 #include <errno.h>
41 #include <stdlib.h>
42 #include <netdb.h>
43 #include <stdio.h>
44 #include <string.h>
45 
46 #include "pcap-int.h"
47 
48 #include "gencode.h"
49 #include <pcap-namedb.h>
50 
51 #ifdef HAVE_OS_PROTO_H
52 #include "os-proto.h"
53 #endif
54 
55 #ifndef NTOHL
56 #define NTOHL(x) (x) = ntohl(x)
57 #define NTOHS(x) (x) = ntohs(x)
58 #endif
59 
60 static __inline int xdtoi(int);
61 
62 /*
63  *  Convert host name to internet address.
64  *  Return 0 upon failure.
65  */
66 bpf_u_int32 **
67 pcap_nametoaddr(const char *name)
68 {
69 #ifndef h_addr
70 	static bpf_u_int32 *hlist[2];
71 #endif
72 	bpf_u_int32 **p;
73 	struct hostent *hp;
74 
75 	if ((hp = gethostbyname(name)) != NULL) {
76 #ifndef h_addr
77 		hlist[0] = (bpf_u_int32 *)hp->h_addr;
78 		NTOHL(hp->h_addr);
79 		return hlist;
80 #else
81 		for (p = (bpf_u_int32 **)hp->h_addr_list; *p; ++p)
82 			NTOHL(**p);
83 		return (bpf_u_int32 **)hp->h_addr_list;
84 #endif
85 	}
86 	else
87 		return 0;
88 }
89 
90 #ifdef INET6
91 struct addrinfo *
92 pcap_nametoaddrinfo(const char *name)
93 {
94 	struct addrinfo hints, *res;
95 	int error;
96 
97 	memset(&hints, 0, sizeof(hints));
98 	hints.ai_family = PF_UNSPEC;
99 	hints.ai_socktype = SOCK_STREAM;	/*not really*/
100 	error = getaddrinfo(name, NULL, &hints, &res);
101 	if (error)
102 		return NULL;
103 	else
104 		return res;
105 }
106 #endif /*INET6*/
107 
108 /*
109  *  Convert net name to internet address.
110  *  Return 0 upon failure.
111  */
112 bpf_u_int32
113 pcap_nametonetaddr(const char *name)
114 {
115 	struct netent *np;
116 
117 	if ((np = getnetbyname(name)) != NULL)
118 		return np->n_net;
119 	else
120 		return 0;
121 }
122 
123 /*
124  * Convert a port name to its port and protocol numbers.
125  * We assume only TCP or UDP.
126  * Return 0 upon failure.
127  */
128 int
129 pcap_nametoport(const char *name, int *port, int *proto)
130 {
131 	struct servent *sp;
132 	char *other;
133 
134 	sp = getservbyname(name, (char *)0);
135 	if (sp != NULL) {
136 		NTOHS(sp->s_port);
137 		*port = sp->s_port;
138 		*proto = pcap_nametoproto(sp->s_proto);
139 		/*
140 		 * We need to check /etc/services for ambiguous entries.
141 		 * If we find the ambiguous entry, and it has the
142 		 * same port number, change the proto to PROTO_UNDEF
143 		 * so both TCP and UDP will be checked.
144 		 */
145 		if (*proto == IPPROTO_TCP)
146 			other = "udp";
147 		else
148 			other = "tcp";
149 
150 		sp = getservbyname(name, other);
151 		if (sp != 0) {
152 			NTOHS(sp->s_port);
153 #ifdef notdef
154 			if (*port != sp->s_port)
155 				/* Can't handle ambiguous names that refer
156 				   to different port numbers. */
157 				warning("ambiguous port %s in /etc/services",
158 					name);
159 #endif
160 			*proto = PROTO_UNDEF;
161 		}
162 		return 1;
163 	}
164 #if defined(ultrix) || defined(__osf__)
165 	/* Special hack in case NFS isn't in /etc/services */
166 	if (strcmp(name, "nfs") == 0) {
167 		*port = 2049;
168 		*proto = PROTO_UNDEF;
169 		return 1;
170 	}
171 #endif
172 	return 0;
173 }
174 
175 int
176 pcap_nametoproto(const char *str)
177 {
178 	struct protoent *p;
179 
180 	p = getprotobyname(str);
181 	if (p != 0)
182 		return p->p_proto;
183 	else
184 		return PROTO_UNDEF;
185 }
186 
187 #include "ethertype.h"
188 
189 struct eproto {
190 	char *s;
191 	u_short p;
192 };
193 
194 /* Static data base of ether protocol types. */
195 static const struct eproto _eproto_db[] = {
196 	{ "pup", ETHERTYPE_PUP },
197 	{ "xns", ETHERTYPE_NS },
198 	{ "ip", ETHERTYPE_IP },
199 #ifdef INET6
200 	{ "ip6", ETHERTYPE_IPV6 },
201 #endif
202 	{ "arp", ETHERTYPE_ARP },
203 	{ "rarp", ETHERTYPE_REVARP },
204 	{ "lldp", ETHERTYPE_LLDP },
205 	{ "slow", ETHERTYPE_SLOW },
206 	{ "sprite", ETHERTYPE_SPRITE },
207 	{ "mopdl", ETHERTYPE_MOPDL },
208 	{ "moprc", ETHERTYPE_MOPRC },
209 	{ "decnet", ETHERTYPE_DN },
210 	{ "lat", ETHERTYPE_LAT },
211 	{ "sca", ETHERTYPE_SCA },
212 	{ "lanbridge", ETHERTYPE_LANBRIDGE },
213 	{ "vexp", ETHERTYPE_VEXP },
214 	{ "vprod", ETHERTYPE_VPROD },
215 	{ "atalk", ETHERTYPE_ATALK },
216 	{ "atalkarp", ETHERTYPE_AARP },
217 	{ "loopback", ETHERTYPE_LOOPBACK },
218 	{ "decdts", ETHERTYPE_DECDTS },
219 	{ "decdns", ETHERTYPE_DECDNS },
220 	{ (char *)0, 0 }
221 };
222 /* Accessor for tcpdump */
223 const struct eproto * const eproto_db = _eproto_db;
224 
225 int
226 pcap_nametoeproto(const char *s)
227 {
228 	const struct eproto *p = _eproto_db;
229 
230 	while (p->s != 0) {
231 		if (strcmp(p->s, s) == 0)
232 			return p->p;
233 		p += 1;
234 	}
235 	return PROTO_UNDEF;
236 }
237 
238 #include "llc.h"
239 
240 /* Static data base of LLC values. */
241 static const struct eproto llc_db[] = {
242 	{ "stp", LLCSAP_8021D },
243 	{ (char *)0, 0 }
244 };
245 
246 int
247 pcap_nametollc(const char *s)
248 {
249 	const struct eproto *p = llc_db;
250 
251 	while (p->s != 0) {
252 		if (strcmp(p->s, s) == 0)
253 			return p->p;
254 		p += 1;
255 	}
256 	return PROTO_UNDEF;
257 }
258 
259 /* Hex digit to integer. */
260 static __inline int
261 xdtoi(c)
262 	int c;
263 {
264 	if (isdigit(c))
265 		return c - '0';
266 	else if (islower(c))
267 		return c - 'a' + 10;
268 	else
269 		return c - 'A' + 10;
270 }
271 
272 int
273 __pcap_atoin(const char *s, bpf_u_int32 *addr)
274 {
275 	u_int n;
276 	int len;
277 
278 	*addr = 0;
279 	len = 0;
280 	while (1) {
281 		n = 0;
282 		while (*s && *s != '.')
283 			n = n * 10 + *s++ - '0';
284 		*addr <<= 8;
285 		*addr |= n & 0xff;
286 		len += 8;
287 		if (*s == '\0')
288 			return len;
289 		++s;
290 	}
291 	/* NOTREACHED */
292 }
293 
294 int
295 __pcap_atodn(const char *s, bpf_u_int32 *addr)
296 {
297 #define AREASHIFT 10
298 #define AREAMASK 0176000
299 #define NODEMASK 01777
300 
301 	u_int node, area;
302 
303 	if (sscanf((char *)s, "%d.%d", &area, &node) != 2)
304 		bpf_error("malformed decnet address '%s'", s);
305 
306 	*addr = (area << AREASHIFT) & AREAMASK;
307 	*addr |= (node & NODEMASK);
308 
309 	return(32);
310 }
311 
312 /*
313  * Convert 's' which has the form "xx:xx:xx:xx:xx:xx" into a new
314  * ethernet address.  Assumes 's' is well formed.
315  */
316 u_char *
317 pcap_ether_aton(const char *s)
318 {
319 	u_char *ep, *e;
320 	u_int d;
321 
322 	e = ep = malloc(6);
323 	if (e == NULL)
324 		bpf_error("malloc");
325 
326 	while (*s) {
327 		if (*s == ':')
328 			s += 1;
329 		d = xdtoi(*s++);
330 		if (isxdigit((unsigned char)*s)) {
331 			d <<= 4;
332 			d |= xdtoi(*s++);
333 		}
334 		*ep++ = d;
335 	}
336 
337 	return (e);
338 }
339 
340 #ifndef HAVE_ETHER_HOSTTON
341 /* Roll our own */
342 u_char *
343 pcap_ether_hostton(const char *name)
344 {
345 	struct pcap_etherent *ep;
346 	u_char *ap;
347 	static FILE *fp = NULL;
348 	static init = 0;
349 
350 	if (!init) {
351 		fp = fopen(PCAP_ETHERS_FILE, "r");
352 		++init;
353 		if (fp == NULL)
354 			return (NULL);
355 	} else if (fp == NULL)
356 		return (NULL);
357 	else
358 		rewind(fp);
359 
360 	while ((ep = pcap_next_etherent(fp)) != NULL) {
361 		if (strcmp(ep->name, name) == 0) {
362 			ap = malloc(6);
363 			if (ap != NULL) {
364 				memcpy(ap, ep->addr, 6);
365 				return (ap);
366 			}
367 			break;
368 		}
369 	}
370 	return (NULL);
371 }
372 #else
373 
374 /* Use the os supplied routines */
375 u_char *
376 pcap_ether_hostton(const char *name)
377 {
378 	u_char *ap;
379 	u_char a[6];
380 
381 	ap = NULL;
382 	if (ether_hostton(name, (struct ether_addr *)a) == 0) {
383 		ap = malloc(6);
384 		if (ap != NULL)
385 			memcpy((char *)ap, (char *)a, 6);
386 	}
387 	return (ap);
388 }
389 #endif
390 
391 u_short
392 __pcap_nametodnaddr(const char *name)
393 {
394 #ifdef	DECNETLIB
395 	struct nodeent *getnodebyname();
396 	struct nodeent *nep;
397 	unsigned short res;
398 
399 	nep = getnodebyname(name);
400 	if (nep == ((struct nodeent *)0))
401 		bpf_error("unknown decnet host name '%s'\n", name);
402 
403 	memcpy((char *)&res, (char *)nep->n_addr, sizeof(unsigned short));
404 	return(res);
405 #else
406 	bpf_error("decnet name support not included, '%s' cannot be translated\n",
407 		name);
408 	/* NOTREACHED */
409 #endif
410 }
411