xref: /openbsd/lib/libpcap/nametoaddr.c (revision d415bd75)
1 /*	$OpenBSD: nametoaddr.c,v 1.24 2021/12/01 18:28:45 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 #include <net/if.h>
32 #include <netinet/in.h>
33 #include <netinet/if_ether.h>
34 #include <arpa/inet.h>
35 
36 #include <ctype.h>
37 #include <errno.h>
38 #include <stdlib.h>
39 #include <netdb.h>
40 #include <stdio.h>
41 #include <string.h>
42 
43 #include "pcap-int.h"
44 
45 #include "gencode.h"
46 #include <pcap-namedb.h>
47 
48 #ifdef HAVE_OS_PROTO_H
49 #include "os-proto.h"
50 #endif
51 
52 #ifndef NTOHL
53 #define NTOHL(x) (x) = ntohl(x)
54 #define NTOHS(x) (x) = ntohs(x)
55 #endif
56 
57 static __inline int xdtoi(int);
58 
59 /*
60  *  Convert host name to internet address.
61  *  Return 0 upon failure.
62  */
63 bpf_u_int32 **
64 pcap_nametoaddr(const char *name)
65 {
66 #ifndef h_addr
67 	static bpf_u_int32 *hlist[2];
68 #endif
69 	bpf_u_int32 **p;
70 	struct hostent *hp;
71 
72 	if ((hp = gethostbyname(name)) != NULL) {
73 #ifndef h_addr
74 		hlist[0] = (bpf_u_int32 *)hp->h_addr;
75 		NTOHL(hp->h_addr);
76 		return hlist;
77 #else
78 		for (p = (bpf_u_int32 **)hp->h_addr_list; *p; ++p)
79 			NTOHL(**p);
80 		return (bpf_u_int32 **)hp->h_addr_list;
81 #endif
82 	}
83 	else
84 		return 0;
85 }
86 
87 #ifdef INET6
88 struct addrinfo *
89 pcap_nametoaddrinfo(const char *name)
90 {
91 	struct addrinfo hints, *res;
92 	int error;
93 
94 	memset(&hints, 0, sizeof(hints));
95 	hints.ai_family = PF_UNSPEC;
96 	hints.ai_socktype = SOCK_STREAM;	/*not really*/
97 	error = getaddrinfo(name, NULL, &hints, &res);
98 	if (error)
99 		return NULL;
100 	else
101 		return res;
102 }
103 #endif /*INET6*/
104 
105 /*
106  *  Convert net name to internet address.
107  *  Return 0 upon failure.
108  */
109 bpf_u_int32
110 pcap_nametonetaddr(const char *name)
111 {
112 	struct netent *np;
113 
114 	if ((np = getnetbyname(name)) != NULL)
115 		return np->n_net;
116 	else
117 		return 0;
118 }
119 
120 /*
121  * Convert a port name to its port and protocol numbers.
122  * We assume only TCP or UDP.
123  * Return 0 upon failure.
124  */
125 int
126 pcap_nametoport(const char *name, int *port, int *proto)
127 {
128 	struct servent *sp;
129 	char *other;
130 
131 	sp = getservbyname(name, (char *)0);
132 	if (sp != NULL) {
133 		NTOHS(sp->s_port);
134 		*port = sp->s_port;
135 		*proto = pcap_nametoproto(sp->s_proto);
136 		/*
137 		 * We need to check /etc/services for ambiguous entries.
138 		 * If we find the ambiguous entry, and it has the
139 		 * same port number, change the proto to PROTO_UNDEF
140 		 * so both TCP and UDP will be checked.
141 		 */
142 		if (*proto == IPPROTO_TCP)
143 			other = "udp";
144 		else
145 			other = "tcp";
146 
147 		sp = getservbyname(name, other);
148 		if (sp != 0) {
149 			NTOHS(sp->s_port);
150 #ifdef notdef
151 			if (*port != sp->s_port)
152 				/* Can't handle ambiguous names that refer
153 				   to different port numbers. */
154 				warning("ambiguous port %s in /etc/services",
155 					name);
156 #endif
157 			*proto = PROTO_UNDEF;
158 		}
159 		return 1;
160 	}
161 #if defined(ultrix) || defined(__osf__)
162 	/* Special hack in case NFS isn't in /etc/services */
163 	if (strcmp(name, "nfs") == 0) {
164 		*port = 2049;
165 		*proto = PROTO_UNDEF;
166 		return 1;
167 	}
168 #endif
169 	return 0;
170 }
171 
172 int
173 pcap_nametoproto(const char *str)
174 {
175 	struct protoent *p;
176 
177 	p = getprotobyname(str);
178 	if (p != 0)
179 		return p->p_proto;
180 	else
181 		return PROTO_UNDEF;
182 }
183 
184 #include "ethertype.h"
185 
186 struct eproto {
187 	char *s;
188 	u_short p;
189 };
190 
191 /* Static data base of ether protocol types. */
192 static const struct eproto _eproto_db[] = {
193 	{ "pup", ETHERTYPE_PUP },
194 	{ "xns", ETHERTYPE_NS },
195 	{ "ip", ETHERTYPE_IP },
196 #ifdef INET6
197 	{ "ip6", ETHERTYPE_IPV6 },
198 #endif
199 	{ "arp", ETHERTYPE_ARP },
200 	{ "rarp", ETHERTYPE_REVARP },
201 	{ "lldp", ETHERTYPE_LLDP },
202 	{ "slow", ETHERTYPE_SLOW },
203 	{ "sprite", ETHERTYPE_SPRITE },
204 	{ "mopdl", ETHERTYPE_MOPDL },
205 	{ "moprc", ETHERTYPE_MOPRC },
206 	{ "decnet", ETHERTYPE_DN },
207 	{ "lat", ETHERTYPE_LAT },
208 	{ "sca", ETHERTYPE_SCA },
209 	{ "lanbridge", ETHERTYPE_LANBRIDGE },
210 	{ "vexp", ETHERTYPE_VEXP },
211 	{ "vprod", ETHERTYPE_VPROD },
212 	{ "atalk", ETHERTYPE_ATALK },
213 	{ "atalkarp", ETHERTYPE_AARP },
214 	{ "loopback", ETHERTYPE_LOOPBACK },
215 	{ "decdts", ETHERTYPE_DECDTS },
216 	{ "decdns", ETHERTYPE_DECDNS },
217 	{ (char *)0, 0 }
218 };
219 /* Accessor for tcpdump */
220 const struct eproto * const eproto_db = _eproto_db;
221 
222 int
223 pcap_nametoeproto(const char *s)
224 {
225 	const struct eproto *p = _eproto_db;
226 
227 	while (p->s != 0) {
228 		if (strcmp(p->s, s) == 0)
229 			return p->p;
230 		p += 1;
231 	}
232 	return PROTO_UNDEF;
233 }
234 
235 #include "llc.h"
236 
237 /* Static data base of LLC values. */
238 static const struct eproto llc_db[] = {
239 	{ "stp", LLCSAP_8021D },
240 	{ (char *)0, 0 }
241 };
242 
243 int
244 pcap_nametollc(const char *s)
245 {
246 	const struct eproto *p = llc_db;
247 
248 	while (p->s != 0) {
249 		if (strcmp(p->s, s) == 0)
250 			return p->p;
251 		p += 1;
252 	}
253 	return PROTO_UNDEF;
254 }
255 
256 /* Hex digit to integer. */
257 static __inline int
258 xdtoi(c)
259 	int c;
260 {
261 	if (isdigit(c))
262 		return c - '0';
263 	else if (islower(c))
264 		return c - 'a' + 10;
265 	else
266 		return c - 'A' + 10;
267 }
268 
269 int
270 __pcap_atoin(const char *s, bpf_u_int32 *addr)
271 {
272 	u_int n;
273 	int len;
274 
275 	*addr = 0;
276 	len = 0;
277 	while (1) {
278 		n = 0;
279 		while (*s && *s != '.')
280 			n = n * 10 + *s++ - '0';
281 		*addr <<= 8;
282 		*addr |= n & 0xff;
283 		len += 8;
284 		if (*s == '\0')
285 			return len;
286 		++s;
287 	}
288 	/* NOTREACHED */
289 }
290 
291 int
292 __pcap_atodn(const char *s, bpf_u_int32 *addr)
293 {
294 #define AREASHIFT 10
295 #define AREAMASK 0176000
296 #define NODEMASK 01777
297 
298 	u_int node, area;
299 
300 	if (sscanf((char *)s, "%d.%d", &area, &node) != 2)
301 		bpf_error("malformed decnet address '%s'", s);
302 
303 	*addr = (area << AREASHIFT) & AREAMASK;
304 	*addr |= (node & NODEMASK);
305 
306 	return(32);
307 }
308 
309 /*
310  * Convert 's' which has the form "xx:xx:xx:xx:xx:xx" into a new
311  * ethernet address.  Assumes 's' is well formed.
312  */
313 u_char *
314 pcap_ether_aton(const char *s)
315 {
316 	u_char *ep, *e;
317 	u_int d;
318 
319 	e = ep = malloc(6);
320 	if (e == NULL)
321 		bpf_error("malloc");
322 
323 	while (*s) {
324 		if (*s == ':')
325 			s += 1;
326 		d = xdtoi(*s++);
327 		if (isxdigit((unsigned char)*s)) {
328 			d <<= 4;
329 			d |= xdtoi(*s++);
330 		}
331 		*ep++ = d;
332 	}
333 
334 	return (e);
335 }
336 
337 #ifndef HAVE_ETHER_HOSTTON
338 /* Roll our own */
339 u_char *
340 pcap_ether_hostton(const char *name)
341 {
342 	struct pcap_etherent *ep;
343 	u_char *ap;
344 	static FILE *fp = NULL;
345 	static init = 0;
346 
347 	if (!init) {
348 		fp = fopen(PCAP_ETHERS_FILE, "r");
349 		++init;
350 		if (fp == NULL)
351 			return (NULL);
352 	} else if (fp == NULL)
353 		return (NULL);
354 	else
355 		rewind(fp);
356 
357 	while ((ep = pcap_next_etherent(fp)) != NULL) {
358 		if (strcmp(ep->name, name) == 0) {
359 			ap = malloc(6);
360 			if (ap != NULL) {
361 				memcpy(ap, ep->addr, 6);
362 				return (ap);
363 			}
364 			break;
365 		}
366 	}
367 	return (NULL);
368 }
369 #else
370 
371 /* Use the os supplied routines */
372 u_char *
373 pcap_ether_hostton(const char *name)
374 {
375 	u_char *ap;
376 	u_char a[6];
377 
378 	ap = NULL;
379 	if (ether_hostton(name, (struct ether_addr *)a) == 0) {
380 		ap = malloc(6);
381 		if (ap != NULL)
382 			memcpy((char *)ap, (char *)a, 6);
383 	}
384 	return (ap);
385 }
386 #endif
387 
388 u_short
389 __pcap_nametodnaddr(const char *name)
390 {
391 #ifdef	DECNETLIB
392 	struct nodeent *getnodebyname();
393 	struct nodeent *nep;
394 	unsigned short res;
395 
396 	nep = getnodebyname(name);
397 	if (nep == ((struct nodeent *)0))
398 		bpf_error("unknown decnet host name '%s'\n", name);
399 
400 	memcpy((char *)&res, (char *)nep->n_addr, sizeof(unsigned short));
401 	return(res);
402 #else
403 	bpf_error("decnet name support not included, '%s' cannot be translated\n",
404 		name);
405 	/* NOTREACHED */
406 #endif
407 }
408