xref: /openbsd/lib/libpcap/nametoaddr.c (revision 19fef815)
1 /*	$OpenBSD: nametoaddr.c,v 1.25 2024/04/05 18:01:56 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 **
pcap_nametoaddr(const char * name)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 *
pcap_nametoaddrinfo(const char * name)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
pcap_nametonetaddr(const char * name)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
pcap_nametoport(const char * name,int * port,int * proto)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
pcap_nametoproto(const char * str)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
pcap_nametoeproto(const char * s)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
pcap_nametollc(const char * s)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
xdtoi(int c)258 xdtoi(int c)
259 {
260 	if (isdigit(c))
261 		return c - '0';
262 	else if (islower(c))
263 		return c - 'a' + 10;
264 	else
265 		return c - 'A' + 10;
266 }
267 
268 int
__pcap_atoin(const char * s,bpf_u_int32 * addr)269 __pcap_atoin(const char *s, bpf_u_int32 *addr)
270 {
271 	u_int n;
272 	int len;
273 
274 	*addr = 0;
275 	len = 0;
276 	while (1) {
277 		n = 0;
278 		while (*s && *s != '.')
279 			n = n * 10 + *s++ - '0';
280 		*addr <<= 8;
281 		*addr |= n & 0xff;
282 		len += 8;
283 		if (*s == '\0')
284 			return len;
285 		++s;
286 	}
287 	/* NOTREACHED */
288 }
289 
290 int
__pcap_atodn(const char * s,bpf_u_int32 * addr)291 __pcap_atodn(const char *s, bpf_u_int32 *addr)
292 {
293 #define AREASHIFT 10
294 #define AREAMASK 0176000
295 #define NODEMASK 01777
296 
297 	u_int node, area;
298 
299 	if (sscanf((char *)s, "%d.%d", &area, &node) != 2)
300 		bpf_error("malformed decnet address '%s'", s);
301 
302 	*addr = (area << AREASHIFT) & AREAMASK;
303 	*addr |= (node & NODEMASK);
304 
305 	return(32);
306 }
307 
308 /*
309  * Convert 's' which has the form "xx:xx:xx:xx:xx:xx" into a new
310  * ethernet address.  Assumes 's' is well formed.
311  */
312 u_char *
pcap_ether_aton(const char * s)313 pcap_ether_aton(const char *s)
314 {
315 	u_char *ep, *e;
316 	u_int d;
317 
318 	e = ep = malloc(6);
319 	if (e == NULL)
320 		bpf_error("malloc");
321 
322 	while (*s) {
323 		if (*s == ':')
324 			s += 1;
325 		d = xdtoi(*s++);
326 		if (isxdigit((unsigned char)*s)) {
327 			d <<= 4;
328 			d |= xdtoi(*s++);
329 		}
330 		*ep++ = d;
331 	}
332 
333 	return (e);
334 }
335 
336 #ifndef HAVE_ETHER_HOSTTON
337 /* Roll our own */
338 u_char *
pcap_ether_hostton(const char * name)339 pcap_ether_hostton(const char *name)
340 {
341 	struct pcap_etherent *ep;
342 	u_char *ap;
343 	static FILE *fp = NULL;
344 	static init = 0;
345 
346 	if (!init) {
347 		fp = fopen(PCAP_ETHERS_FILE, "r");
348 		++init;
349 		if (fp == NULL)
350 			return (NULL);
351 	} else if (fp == NULL)
352 		return (NULL);
353 	else
354 		rewind(fp);
355 
356 	while ((ep = pcap_next_etherent(fp)) != NULL) {
357 		if (strcmp(ep->name, name) == 0) {
358 			ap = malloc(6);
359 			if (ap != NULL) {
360 				memcpy(ap, ep->addr, 6);
361 				return (ap);
362 			}
363 			break;
364 		}
365 	}
366 	return (NULL);
367 }
368 #else
369 
370 /* Use the os supplied routines */
371 u_char *
pcap_ether_hostton(const char * name)372 pcap_ether_hostton(const char *name)
373 {
374 	u_char *ap;
375 	u_char a[6];
376 
377 	ap = NULL;
378 	if (ether_hostton(name, (struct ether_addr *)a) == 0) {
379 		ap = malloc(6);
380 		if (ap != NULL)
381 			memcpy((char *)ap, (char *)a, 6);
382 	}
383 	return (ap);
384 }
385 #endif
386 
387 u_short
__pcap_nametodnaddr(const char * name)388 __pcap_nametodnaddr(const char *name)
389 {
390 #ifdef	DECNETLIB
391 	struct nodeent *getnodebyname();
392 	struct nodeent *nep;
393 	unsigned short res;
394 
395 	nep = getnodebyname(name);
396 	if (nep == ((struct nodeent *)0))
397 		bpf_error("unknown decnet host name '%s'\n", name);
398 
399 	memcpy((char *)&res, (char *)nep->n_addr, sizeof(unsigned short));
400 	return(res);
401 #else
402 	bpf_error("decnet name support not included, '%s' cannot be translated\n",
403 		name);
404 	/* NOTREACHED */
405 #endif
406 }
407