xref: /freebsd/contrib/libpcap/nametoaddr.c (revision 8aac90f18aef7c9eea906c3ff9a001ca7b94f375)
1 /*
2  * Copyright (c) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that: (1) source code distributions
7  * retain the above copyright notice and this paragraph in its entirety, (2)
8  * distributions including binary code include the above copyright notice and
9  * this paragraph in its entirety in the documentation or other materials
10  * provided with the distribution, and (3) all advertising materials mentioning
11  * features or use of this software display the following acknowledgement:
12  * ``This product includes software developed by the University of California,
13  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
14  * the University nor the names of its contributors may be used to endorse
15  * or promote products derived from this software without specific prior
16  * written permission.
17  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
18  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
20  *
21  * Name to id translation routines used by the scanner.
22  * These functions are not time critical.
23  */
24 
25 #ifdef HAVE_CONFIG_H
26 #include <config.h>
27 #endif
28 
29 #ifdef DECNETLIB
30 #include <sys/types.h>
31 #include <netdnet/dnetdb.h>
32 #endif
33 
34 #ifdef _WIN32
35   #include <winsock2.h>
36   #include <ws2tcpip.h>
37 
38   #ifdef INET6
39     /*
40      * To quote the MSDN page for getaddrinfo() at
41      *
42      *    https://msdn.microsoft.com/en-us/library/windows/desktop/ms738520(v=vs.85).aspx
43      *
44      * "Support for getaddrinfo on Windows 2000 and older versions
45      * The getaddrinfo function was added to the Ws2_32.dll on Windows XP and
46      * later. To execute an application that uses this function on earlier
47      * versions of Windows, then you need to include the Ws2tcpip.h and
48      * Wspiapi.h files. When the Wspiapi.h include file is added, the
49      * getaddrinfo function is defined to the WspiapiGetAddrInfo inline
50      * function in the Wspiapi.h file. At runtime, the WspiapiGetAddrInfo
51      * function is implemented in such a way that if the Ws2_32.dll or the
52      * Wship6.dll (the file containing getaddrinfo in the IPv6 Technology
53      * Preview for Windows 2000) does not include getaddrinfo, then a
54      * version of getaddrinfo is implemented inline based on code in the
55      * Wspiapi.h header file. This inline code will be used on older Windows
56      * platforms that do not natively support the getaddrinfo function."
57      *
58      * We use getaddrinfo(), so we include Wspiapi.h here.
59      */
60     #include <wspiapi.h>
61   #endif /* INET6 */
62 #else /* _WIN32 */
63   #include <sys/param.h>
64   #include <sys/types.h>
65   #include <sys/socket.h>
66   #include <sys/time.h>
67 
68   #include <netinet/in.h>
69 
70   #ifdef HAVE_ETHER_HOSTTON
71     #if defined(NET_ETHERNET_H_DECLARES_ETHER_HOSTTON)
72       /*
73        * OK, just include <net/ethernet.h>.
74        */
75       #include <net/ethernet.h>
76     #elif defined(NETINET_ETHER_H_DECLARES_ETHER_HOSTTON)
77       /*
78        * OK, just include <netinet/ether.h>
79        */
80       #include <netinet/ether.h>
81     #elif defined(SYS_ETHERNET_H_DECLARES_ETHER_HOSTTON)
82       /*
83        * OK, just include <sys/ethernet.h>
84        */
85       #include <sys/ethernet.h>
86     #elif defined(ARPA_INET_H_DECLARES_ETHER_HOSTTON)
87       /*
88        * OK, just include <arpa/inet.h>
89        */
90       #include <arpa/inet.h>
91     #elif defined(NETINET_IF_ETHER_H_DECLARES_ETHER_HOSTTON)
92       /*
93        * OK, include <netinet/if_ether.h>, after all the other stuff we
94        * need to include or define for its benefit.
95        */
96       #define NEED_NETINET_IF_ETHER_H
97     #else
98       /*
99        * We'll have to declare it ourselves.
100        * If <netinet/if_ether.h> defines struct ether_addr, include
101        * it.  Otherwise, define it ourselves.
102        */
103       #ifdef HAVE_STRUCT_ETHER_ADDR
104         #define NEED_NETINET_IF_ETHER_H
105       #else /* HAVE_STRUCT_ETHER_ADDR */
106 	struct ether_addr {
107 		unsigned char ether_addr_octet[6];
108 	};
109       #endif /* HAVE_STRUCT_ETHER_ADDR */
110     #endif /* what declares ether_hostton() */
111 
112     #ifdef NEED_NETINET_IF_ETHER_H
113       #include <net/if.h>	/* Needed on some platforms */
114       #include <netinet/in.h>	/* Needed on some platforms */
115       #include <netinet/if_ether.h>
116     #endif /* NEED_NETINET_IF_ETHER_H */
117 
118     #ifndef HAVE_DECL_ETHER_HOSTTON
119       /*
120        * No header declares it, so declare it ourselves.
121        */
122       extern int ether_hostton(const char *, struct ether_addr *);
123     #endif /* !defined(HAVE_DECL_ETHER_HOSTTON) */
124   #endif /* HAVE_ETHER_HOSTTON */
125 
126   #include <arpa/inet.h>
127   #include <netdb.h>
128 #endif /* _WIN32 */
129 
130 #include <errno.h>
131 #include <stdlib.h>
132 #include <string.h>
133 #include <stdio.h>
134 
135 #include "pcap-int.h"
136 
137 #include "diag-control.h"
138 
139 #include "gencode.h"
140 #include <pcap/namedb.h>
141 #include "nametoaddr.h"
142 
143 #ifdef HAVE_OS_PROTO_H
144 #include "os-proto.h"
145 #endif
146 
147 #ifndef NTOHL
148 #define NTOHL(x) (x) = ntohl(x)
149 #define NTOHS(x) (x) = ntohs(x)
150 #endif
151 
152 /*
153  *  Convert host name to internet address.
154  *  Return 0 upon failure.
155  *  XXX - not thread-safe; don't use it inside libpcap.
156  */
157 bpf_u_int32 **
158 pcap_nametoaddr(const char *name)
159 {
160 #ifndef h_addr
161 	static bpf_u_int32 *hlist[2];
162 #endif
163 	bpf_u_int32 **p;
164 	struct hostent *hp;
165 
166 	/*
167 	 * gethostbyname() is deprecated on Windows, perhaps because
168 	 * it's not thread-safe, or because it doesn't support IPv6,
169 	 * or both.
170 	 *
171 	 * We deprecate pcap_nametoaddr() on all platforms because
172 	 * it's not thread-safe; we supply it for backwards compatibility,
173 	 * so suppress the deprecation warning.  We could, I guess,
174 	 * use getaddrinfo() and construct the array ourselves, but
175 	 * that's probably not worth the effort, as that wouldn't make
176 	 * this thread-safe - we can't change the API to require that
177 	 * our caller free the address array, so we still have to reuse
178 	 * a local array.
179 	 */
180 DIAG_OFF_DEPRECATION
181 	if ((hp = gethostbyname(name)) != NULL) {
182 DIAG_ON_DEPRECATION
183 #ifndef h_addr
184 		hlist[0] = (bpf_u_int32 *)hp->h_addr;
185 		NTOHL(hp->h_addr);
186 		return hlist;
187 #else
188 		for (p = (bpf_u_int32 **)hp->h_addr_list; *p; ++p)
189 			NTOHL(**p);
190 		return (bpf_u_int32 **)hp->h_addr_list;
191 #endif
192 	}
193 	else
194 		return 0;
195 }
196 
197 struct addrinfo *
198 pcap_nametoaddrinfo(const char *name)
199 {
200 	struct addrinfo hints, *res;
201 	int error;
202 
203 	memset(&hints, 0, sizeof(hints));
204 	hints.ai_family = PF_UNSPEC;
205 	hints.ai_socktype = SOCK_STREAM;	/*not really*/
206 	hints.ai_protocol = IPPROTO_TCP;	/*not really*/
207 	error = getaddrinfo(name, NULL, &hints, &res);
208 	if (error)
209 		return NULL;
210 	else
211 		return res;
212 }
213 
214 /*
215  *  Convert net name to internet address.
216  *  Return 0 upon failure.
217  *  XXX - not guaranteed to be thread-safe!  See below for platforms
218  *  on which it is thread-safe and on which it isn't.
219  */
220 #if defined(_WIN32) || defined(__CYGWIN__)
221 bpf_u_int32
222 pcap_nametonetaddr(const char *name _U_)
223 {
224 	/*
225 	 * There's no "getnetbyname()" on Windows.
226 	 *
227 	 * XXX - I guess we could use the BSD code to read
228 	 * C:\Windows\System32\drivers\etc/networks, assuming
229 	 * that's its home on all the versions of Windows
230 	 * we use, but that file probably just has the loopback
231 	 * network on 127/24 on 99 44/100% of Windows machines.
232 	 *
233 	 * (Heck, these days it probably just has that on 99 44/100%
234 	 * of *UN*X* machines.)
235 	 */
236 	return 0;
237 }
238 #else /* _WIN32 */
239 bpf_u_int32
240 pcap_nametonetaddr(const char *name)
241 {
242 	/*
243 	 * UN*X.
244 	 */
245 	struct netent *np;
246   #if defined(HAVE_LINUX_GETNETBYNAME_R)
247 	/*
248 	 * We have Linux's reentrant getnetbyname_r().
249 	 */
250 	struct netent result_buf;
251 	char buf[1024];	/* arbitrary size */
252 	int h_errnoval;
253 	int err;
254 
255 	/*
256 	 * Apparently, the man page at
257 	 *
258 	 *    http://man7.org/linux/man-pages/man3/getnetbyname_r.3.html
259 	 *
260 	 * lies when it says
261 	 *
262 	 *    If the function call successfully obtains a network record,
263 	 *    then *result is set pointing to result_buf; otherwise, *result
264 	 *    is set to NULL.
265 	 *
266 	 * and, in fact, at least in some versions of GNU libc, it does
267 	 * *not* always get set if getnetbyname_r() succeeds.
268 	 */
269 	np = NULL;
270 	err = getnetbyname_r(name, &result_buf, buf, sizeof buf, &np,
271 	    &h_errnoval);
272 	if (err != 0) {
273 		/*
274 		 * XXX - dynamically allocate the buffer, and make it
275 		 * bigger if we get ERANGE back?
276 		 */
277 		return 0;
278 	}
279   #elif defined(HAVE_SOLARIS_IRIX_GETNETBYNAME_R)
280 	/*
281 	 * We have Solaris's and IRIX's reentrant getnetbyname_r().
282 	 */
283 	struct netent result_buf;
284 	char buf[1024];	/* arbitrary size */
285 
286 	np = getnetbyname_r(name, &result_buf, buf, (int)sizeof buf);
287   #elif defined(HAVE_AIX_GETNETBYNAME_R)
288 	/*
289 	 * We have AIX's reentrant getnetbyname_r().
290 	 */
291 	struct netent result_buf;
292 	struct netent_data net_data;
293 
294 	if (getnetbyname_r(name, &result_buf, &net_data) == -1)
295 		np = NULL;
296 	else
297 		np = &result_buf;
298   #else
299 	/*
300 	 * We don't have any getnetbyname_r(); either we have a
301 	 * getnetbyname() that uses thread-specific data, in which
302 	 * case we're thread-safe (sufficiently recent FreeBSD,
303 	 * sufficiently recent Darwin-based OS, sufficiently recent
304 	 * HP-UX, sufficiently recent Tru64 UNIX), or we have the
305 	 * traditional getnetbyname() (everything else, including
306 	 * current NetBSD and OpenBSD), in which case we're not
307 	 * thread-safe.
308 	 */
309 	np = getnetbyname(name);
310   #endif
311 	if (np != NULL)
312 		return np->n_net;
313 	else
314 		return 0;
315 }
316 #endif /* _WIN32 */
317 
318 /*
319  * Convert a port name to its port and protocol numbers.
320  * We assume only TCP or UDP.
321  * Return 0 upon failure.
322  */
323 int
324 pcap_nametoport(const char *name, int *port, int *proto)
325 {
326 	struct addrinfo hints, *res, *ai;
327 	int error;
328 	struct sockaddr_in *in4;
329 #ifdef INET6
330 	struct sockaddr_in6 *in6;
331 #endif
332 	int tcp_port = -1;
333 	int udp_port = -1;
334 
335 	/*
336 	 * We check for both TCP and UDP in case there are
337 	 * ambiguous entries.
338 	 */
339 	memset(&hints, 0, sizeof(hints));
340 	hints.ai_family = PF_UNSPEC;
341 	hints.ai_socktype = SOCK_STREAM;
342 	hints.ai_protocol = IPPROTO_TCP;
343 	error = getaddrinfo(NULL, name, &hints, &res);
344 	if (error != 0) {
345 		if (error != EAI_NONAME &&
346 		    error != EAI_SERVICE) {
347 			/*
348 			 * This is a real error, not just "there's
349 			 * no such service name".
350 			 * XXX - this doesn't return an error string.
351 			 */
352 			return 0;
353 		}
354 	} else {
355 		/*
356 		 * OK, we found it.  Did it find anything?
357 		 */
358 		for (ai = res; ai != NULL; ai = ai->ai_next) {
359 			/*
360 			 * Does it have an address?
361 			 */
362 			if (ai->ai_addr != NULL) {
363 				/*
364 				 * Yes.  Get a port number; we're done.
365 				 */
366 				if (ai->ai_addr->sa_family == AF_INET) {
367 					in4 = (struct sockaddr_in *)ai->ai_addr;
368 					tcp_port = ntohs(in4->sin_port);
369 					break;
370 				}
371 #ifdef INET6
372 				if (ai->ai_addr->sa_family == AF_INET6) {
373 					in6 = (struct sockaddr_in6 *)ai->ai_addr;
374 					tcp_port = ntohs(in6->sin6_port);
375 					break;
376 				}
377 #endif
378 			}
379 		}
380 		freeaddrinfo(res);
381 	}
382 
383 	memset(&hints, 0, sizeof(hints));
384 	hints.ai_family = PF_UNSPEC;
385 	hints.ai_socktype = SOCK_DGRAM;
386 	hints.ai_protocol = IPPROTO_UDP;
387 	error = getaddrinfo(NULL, name, &hints, &res);
388 	if (error != 0) {
389 		if (error != EAI_NONAME &&
390 		    error != EAI_SERVICE) {
391 			/*
392 			 * This is a real error, not just "there's
393 			 * no such service name".
394 			 * XXX - this doesn't return an error string.
395 			 */
396 			return 0;
397 		}
398 	} else {
399 		/*
400 		 * OK, we found it.  Did it find anything?
401 		 */
402 		for (ai = res; ai != NULL; ai = ai->ai_next) {
403 			/*
404 			 * Does it have an address?
405 			 */
406 			if (ai->ai_addr != NULL) {
407 				/*
408 				 * Yes.  Get a port number; we're done.
409 				 */
410 				if (ai->ai_addr->sa_family == AF_INET) {
411 					in4 = (struct sockaddr_in *)ai->ai_addr;
412 					udp_port = ntohs(in4->sin_port);
413 					break;
414 				}
415 #ifdef INET6
416 				if (ai->ai_addr->sa_family == AF_INET6) {
417 					in6 = (struct sockaddr_in6 *)ai->ai_addr;
418 					udp_port = ntohs(in6->sin6_port);
419 					break;
420 				}
421 #endif
422 			}
423 		}
424 		freeaddrinfo(res);
425 	}
426 
427 	/*
428 	 * We need to check /etc/services for ambiguous entries.
429 	 * If we find an ambiguous entry, and it has the
430 	 * same port number, change the proto to PROTO_UNDEF
431 	 * so both TCP and UDP will be checked.
432 	 */
433 	if (tcp_port >= 0) {
434 		*port = tcp_port;
435 		*proto = IPPROTO_TCP;
436 		if (udp_port >= 0) {
437 			if (udp_port == tcp_port)
438 				*proto = PROTO_UNDEF;
439 #ifdef notdef
440 			else
441 				/* Can't handle ambiguous names that refer
442 				   to different port numbers. */
443 				warning("ambiguous port %s in /etc/services",
444 					name);
445 #endif
446 		}
447 		return 1;
448 	}
449 	if (udp_port >= 0) {
450 		*port = udp_port;
451 		*proto = IPPROTO_UDP;
452 		return 1;
453 	}
454 #if defined(ultrix) || defined(__osf__)
455 	/* Special hack in case NFS isn't in /etc/services */
456 	if (strcmp(name, "nfs") == 0) {
457 		*port = 2049;
458 		*proto = PROTO_UNDEF;
459 		return 1;
460 	}
461 #endif
462 	return 0;
463 }
464 
465 /*
466  * Convert a string in the form PPP-PPP, where correspond to ports, to
467  * a starting and ending port in a port range.
468  * Return 0 on failure.
469  */
470 int
471 pcap_nametoportrange(const char *name, int *port1, int *port2, int *proto)
472 {
473 	u_int p1, p2;
474 	char *off, *cpy;
475 	int save_proto;
476 
477 	if (sscanf(name, "%d-%d", &p1, &p2) != 2) {
478 		if ((cpy = strdup(name)) == NULL)
479 			return 0;
480 
481 		if ((off = strchr(cpy, '-')) == NULL) {
482 			free(cpy);
483 			return 0;
484 		}
485 
486 		*off = '\0';
487 
488 		if (pcap_nametoport(cpy, port1, proto) == 0) {
489 			free(cpy);
490 			return 0;
491 		}
492 		save_proto = *proto;
493 
494 		if (pcap_nametoport(off + 1, port2, proto) == 0) {
495 			free(cpy);
496 			return 0;
497 		}
498 		free(cpy);
499 
500 		if (*proto != save_proto)
501 			*proto = PROTO_UNDEF;
502 	} else {
503 		*port1 = p1;
504 		*port2 = p2;
505 		*proto = PROTO_UNDEF;
506 	}
507 
508 	return 1;
509 }
510 
511 /*
512  * XXX - not guaranteed to be thread-safe!  See below for platforms
513  * on which it is thread-safe and on which it isn't.
514  */
515 int
516 pcap_nametoproto(const char *str)
517 {
518 	struct protoent *p;
519   #if defined(HAVE_LINUX_GETNETBYNAME_R)
520 	/*
521 	 * We have Linux's reentrant getprotobyname_r().
522 	 */
523 	struct protoent result_buf;
524 	char buf[1024];	/* arbitrary size */
525 	int err;
526 
527 	err = getprotobyname_r(str, &result_buf, buf, sizeof buf, &p);
528 	if (err != 0) {
529 		/*
530 		 * XXX - dynamically allocate the buffer, and make it
531 		 * bigger if we get ERANGE back?
532 		 */
533 		return 0;
534 	}
535   #elif defined(HAVE_SOLARIS_IRIX_GETNETBYNAME_R)
536 	/*
537 	 * We have Solaris's and IRIX's reentrant getprotobyname_r().
538 	 */
539 	struct protoent result_buf;
540 	char buf[1024];	/* arbitrary size */
541 
542 	p = getprotobyname_r(str, &result_buf, buf, (int)sizeof buf);
543   #elif defined(HAVE_AIX_GETNETBYNAME_R)
544 	/*
545 	 * We have AIX's reentrant getprotobyname_r().
546 	 */
547 	struct protoent result_buf;
548 	struct protoent_data proto_data;
549 
550 	if (getprotobyname_r(str, &result_buf, &proto_data) == -1)
551 		p = NULL;
552 	else
553 		p = &result_buf;
554   #else
555 	/*
556 	 * We don't have any getprotobyname_r(); either we have a
557 	 * getprotobyname() that uses thread-specific data, in which
558 	 * case we're thread-safe (sufficiently recent FreeBSD,
559 	 * sufficiently recent Darwin-based OS, sufficiently recent
560 	 * HP-UX, sufficiently recent Tru64 UNIX, Windows), or we have
561 	 * the traditional getprotobyname() (everything else, including
562 	 * current NetBSD and OpenBSD), in which case we're not
563 	 * thread-safe.
564 	 */
565 	p = getprotobyname(str);
566   #endif
567 	if (p != 0)
568 		return p->p_proto;
569 	else
570 		return PROTO_UNDEF;
571 }
572 
573 #include "ethertype.h"
574 
575 struct eproto {
576 	const char *s;
577 	u_short p;
578 };
579 
580 /*
581  * Static data base of ether protocol types.
582  * tcpdump used to import this, and it's declared as an export on
583  * Debian, at least, so make it a public symbol, even though we
584  * don't officially export it by declaring it in a header file.
585  * (Programs *should* do this themselves, as tcpdump now does.)
586  *
587  * We declare it here, right before defining it, to squelch any
588  * warnings we might get from compilers about the lack of a
589  * declaration.
590  */
591 PCAP_API struct eproto eproto_db[];
592 PCAP_API_DEF struct eproto eproto_db[] = {
593 	{ "aarp", ETHERTYPE_AARP },
594 	{ "arp", ETHERTYPE_ARP },
595 	{ "atalk", ETHERTYPE_ATALK },
596 	{ "decnet", ETHERTYPE_DN },
597 	{ "ip", ETHERTYPE_IP },
598 #ifdef INET6
599 	{ "ip6", ETHERTYPE_IPV6 },
600 #endif
601 	{ "lat", ETHERTYPE_LAT },
602 	{ "loopback", ETHERTYPE_LOOPBACK },
603 	{ "mopdl", ETHERTYPE_MOPDL },
604 	{ "moprc", ETHERTYPE_MOPRC },
605 	{ "rarp", ETHERTYPE_REVARP },
606 	{ "sca", ETHERTYPE_SCA },
607 	{ (char *)0, 0 }
608 };
609 
610 int
611 pcap_nametoeproto(const char *s)
612 {
613 	struct eproto *p = eproto_db;
614 
615 	while (p->s != 0) {
616 		if (strcmp(p->s, s) == 0)
617 			return p->p;
618 		p += 1;
619 	}
620 	return PROTO_UNDEF;
621 }
622 
623 #include "llc.h"
624 
625 /* Static data base of LLC values. */
626 static struct eproto llc_db[] = {
627 	{ "iso", LLCSAP_ISONS },
628 	{ "stp", LLCSAP_8021D },
629 	{ "ipx", LLCSAP_IPX },
630 	{ "netbeui", LLCSAP_NETBEUI },
631 	{ (char *)0, 0 }
632 };
633 
634 int
635 pcap_nametollc(const char *s)
636 {
637 	struct eproto *p = llc_db;
638 
639 	while (p->s != 0) {
640 		if (strcmp(p->s, s) == 0)
641 			return p->p;
642 		p += 1;
643 	}
644 	return PROTO_UNDEF;
645 }
646 
647 /* Hex digit to 8-bit unsigned integer. */
648 static inline u_char
649 xdtoi(u_char c)
650 {
651 	if (c >= '0' && c <= '9')
652 		return (u_char)(c - '0');
653 	else if (c >= 'a' && c <= 'f')
654 		return (u_char)(c - 'a' + 10);
655 	else
656 		return (u_char)(c - 'A' + 10);
657 }
658 
659 int
660 __pcap_atoin(const char *s, bpf_u_int32 *addr)
661 {
662 	u_int n;
663 	int len;
664 
665 	*addr = 0;
666 	len = 0;
667 	for (;;) {
668 		n = 0;
669 		while (*s && *s != '.') {
670 			if (n > 25) {
671 				/* The result will be > 255 */
672 				return -1;
673 			}
674 			n = n * 10 + *s++ - '0';
675 		}
676 		if (n > 255)
677 			return -1;
678 		*addr <<= 8;
679 		*addr |= n & 0xff;
680 		len += 8;
681 		if (*s == '\0')
682 			return len;
683 		++s;
684 	}
685 	/* NOTREACHED */
686 }
687 
688 int
689 __pcap_atodn(const char *s, bpf_u_int32 *addr)
690 {
691 #define AREASHIFT 10
692 #define AREAMASK 0176000
693 #define NODEMASK 01777
694 
695 	u_int node, area;
696 
697 	if (sscanf(s, "%d.%d", &area, &node) != 2)
698 		return(0);
699 
700 	*addr = (area << AREASHIFT) & AREAMASK;
701 	*addr |= (node & NODEMASK);
702 
703 	return(32);
704 }
705 
706 /*
707  * Convert 's', which can have the one of the forms:
708  *
709  *	"xx:xx:xx:xx:xx:xx"
710  *	"xx.xx.xx.xx.xx.xx"
711  *	"xx-xx-xx-xx-xx-xx"
712  *	"xxxx.xxxx.xxxx"
713  *	"xxxxxxxxxxxx"
714  *
715  * (or various mixes of ':', '.', and '-') into a new
716  * ethernet address.  Assumes 's' is well formed.
717  */
718 u_char *
719 pcap_ether_aton(const char *s)
720 {
721 	register u_char *ep, *e;
722 	register u_char d;
723 
724 	e = ep = (u_char *)malloc(6);
725 	if (e == NULL)
726 		return (NULL);
727 
728 	while (*s) {
729 		if (*s == ':' || *s == '.' || *s == '-')
730 			s += 1;
731 		d = xdtoi(*s++);
732 		if (PCAP_ISXDIGIT(*s)) {
733 			d <<= 4;
734 			d |= xdtoi(*s++);
735 		}
736 		*ep++ = d;
737 	}
738 
739 	return (e);
740 }
741 
742 #ifndef HAVE_ETHER_HOSTTON
743 /*
744  * Roll our own.
745  * XXX - not thread-safe, because pcap_next_etherent() isn't thread-
746  * safe!  Needs a mutex or a thread-safe pcap_next_etherent().
747  */
748 u_char *
749 pcap_ether_hostton(const char *name)
750 {
751 	register struct pcap_etherent *ep;
752 	register u_char *ap;
753 	static FILE *fp = NULL;
754 	static int init = 0;
755 
756 	if (!init) {
757 		fp = fopen(PCAP_ETHERS_FILE, "r");
758 		++init;
759 		if (fp == NULL)
760 			return (NULL);
761 	} else if (fp == NULL)
762 		return (NULL);
763 	else
764 		rewind(fp);
765 
766 	while ((ep = pcap_next_etherent(fp)) != NULL) {
767 		if (strcmp(ep->name, name) == 0) {
768 			ap = (u_char *)malloc(6);
769 			if (ap != NULL) {
770 				memcpy(ap, ep->addr, 6);
771 				return (ap);
772 			}
773 			break;
774 		}
775 	}
776 	return (NULL);
777 }
778 #else
779 /*
780  * Use the OS-supplied routine.
781  * This *should* be thread-safe; the API doesn't have a static buffer.
782  */
783 u_char *
784 pcap_ether_hostton(const char *name)
785 {
786 	register u_char *ap;
787 	u_char a[6];
788 	char namebuf[1024];
789 
790 	/*
791 	 * In AIX 7.1 and 7.2: int ether_hostton(char *, struct ether_addr *);
792 	 */
793 	pcap_strlcpy(namebuf, name, sizeof(namebuf));
794 	ap = NULL;
795 	if (ether_hostton(namebuf, (struct ether_addr *)a) == 0) {
796 		ap = (u_char *)malloc(6);
797 		if (ap != NULL)
798 			memcpy((char *)ap, (char *)a, 6);
799 	}
800 	return (ap);
801 }
802 #endif
803 
804 /*
805  * XXX - not guaranteed to be thread-safe!
806  */
807 int
808 #ifdef	DECNETLIB
809 __pcap_nametodnaddr(const char *name, u_short *res)
810 {
811 	struct nodeent *getnodebyname();
812 	struct nodeent *nep;
813 
814 	nep = getnodebyname(name);
815 	if (nep == ((struct nodeent *)0))
816 		return(0);
817 
818 	memcpy((char *)res, (char *)nep->n_addr, sizeof(unsigned short));
819 	return(1);
820 #else
821 __pcap_nametodnaddr(const char *name _U_, u_short *res _U_)
822 {
823 	return(0);
824 #endif
825 }
826