The Tcpdump Group git mirrors - libpcap/blob - nametoaddr.c

   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 #include <config.h>
  26
  27 #ifdef _WIN32
  28   #include <winsock2.h>
  29   #include <ws2tcpip.h>
  30 #else /* _WIN32 */
  31   #include <sys/param.h>
  32   #include <sys/types.h>
  33   #include <sys/socket.h>
  34   #include <sys/time.h>
  35
  36   #include <netinet/in.h>
  37
  38   #ifdef HAVE_ETHER_HOSTTON
  39     #if defined(NET_ETHERNET_H_DECLARES_ETHER_HOSTTON)
  40       /*
  41        * OK, just include <net/ethernet.h>.
  42        */
  43       #include <net/ethernet.h>
  44     #elif defined(NETINET_ETHER_H_DECLARES_ETHER_HOSTTON)
  45       /*
  46        * OK, just include <netinet/ether.h>
  47        */
  48       #include <netinet/ether.h>
  49     #elif defined(SYS_ETHERNET_H_DECLARES_ETHER_HOSTTON)
  50       /*
  51        * OK, just include <sys/ethernet.h>
  52        */
  53       #include <sys/ethernet.h>
  54     #elif defined(ARPA_INET_H_DECLARES_ETHER_HOSTTON)
  55       /*
  56        * OK, just include <arpa/inet.h>
  57        */
  58       #include <arpa/inet.h>
  59     #elif defined(NETINET_IF_ETHER_H_DECLARES_ETHER_HOSTTON)
  60       /*
  61        * OK, include <netinet/if_ether.h>, after all the other stuff we
  62        * need to include or define for its benefit.
  63        */
  64       #define NEED_NETINET_IF_ETHER_H
  65     #else
  66       /*
  67        * We'll have to declare it ourselves.
  68        * If <netinet/if_ether.h> defines struct ether_addr, include
  69        * it.  Otherwise, define it ourselves.
  70        */
  71       #ifdef HAVE_STRUCT_ETHER_ADDR
  72         #define NEED_NETINET_IF_ETHER_H
  73       #else /* HAVE_STRUCT_ETHER_ADDR */
  74         struct ether_addr {
  75                 unsigned char ether_addr_octet[6];
  76         };
  77       #endif /* HAVE_STRUCT_ETHER_ADDR */
  78     #endif /* what declares ether_hostton() */
  79
  80     #ifdef NEED_NETINET_IF_ETHER_H
  81       #include <net/if.h>       /* Needed on some platforms */
  82       #include <netinet/in.h>   /* Needed on some platforms */
  83       #include <netinet/if_ether.h>
  84     #endif /* NEED_NETINET_IF_ETHER_H */
  85
  86     #ifndef HAVE_DECL_ETHER_HOSTTON
  87       /*
  88        * No header declares it, so declare it ourselves.
  89        */
  90       extern int ether_hostton(const char *, struct ether_addr *);
  91     #endif /* !defined(HAVE_DECL_ETHER_HOSTTON) */
  92   #endif /* HAVE_ETHER_HOSTTON */
  93
  94   #include <arpa/inet.h>
  95   #include <netdb.h>
  96 #endif /* _WIN32 */
  97
  98 #include <errno.h>
  99 #include <stdlib.h>
 100 #include <string.h>
 101 #include <stdio.h>
 102
 103 #include "pcap-int.h"
 104
 105 #include "diag-control.h"
 106
 107 #include "gencode.h"
 108 #include <pcap/namedb.h>
 109 #include "nametoaddr.h"
 110
 111 #include "thread-local.h"
 112
 113 #ifdef HAVE_OS_PROTO_H
 114 #include "os-proto.h"
 115 #endif
 116
 117 #ifndef NTOHL
 118 #define NTOHL(x) (x) = ntohl(x)
 119 #define NTOHS(x) (x) = ntohs(x)
 120 #endif
 121
 122 /*
 123  *  Convert host name to internet address.
 124  *  Return 0 upon failure.
 125  *  XXX - not thread-safe; don't use it inside libpcap.
 126  */
 127 bpf_u_int32 **
 128 pcap_nametoaddr(const char *name)
 129 {
 130 #ifndef h_addr
 131         static bpf_u_int32 *hlist[2];
 132 #endif
 133         bpf_u_int32 **p;
 134         struct hostent *hp;
 135
 136         /*
 137          * gethostbyname() is deprecated on Windows, perhaps because
 138          * it's not thread-safe, or because it doesn't support IPv6,
 139          * or both.
 140          *
 141          * We deprecate pcap_nametoaddr() on all platforms because
 142          * it's not thread-safe; we supply it for backwards compatibility,
 143          * so suppress the deprecation warning.  We could, I guess,
 144          * use getaddrinfo() and construct the array ourselves, but
 145          * that's probably not worth the effort, as that wouldn't make
 146          * this thread-safe - we can't change the API to require that
 147          * our caller free the address array, so we still have to reuse
 148          * a local array.
 149          */
 150 DIAG_OFF_DEPRECATION
 151         if ((hp = gethostbyname(name)) != NULL) {
 152 DIAG_ON_DEPRECATION
 153 #ifndef h_addr
 154                 hlist[0] = (bpf_u_int32 *)hp->h_addr;
 155                 NTOHL(hp->h_addr);
 156                 return hlist;
 157 #else
 158                 for (p = (bpf_u_int32 **)hp->h_addr_list; *p; ++p)
 159                         NTOHL(**p);
 160                 return (bpf_u_int32 **)hp->h_addr_list;
 161 #endif
 162         }
 163         else
 164                 return 0;
 165 }
 166
 167 struct addrinfo *
 168 pcap_nametoaddrinfo(const char *name)
 169 {
 170         struct addrinfo hints, *res;
 171         int error;
 172
 173         memset(&hints, 0, sizeof(hints));
 174         hints.ai_family = PF_UNSPEC;
 175         hints.ai_socktype = SOCK_STREAM;        /*not really*/
 176         hints.ai_protocol = IPPROTO_TCP;        /*not really*/
 177         error = getaddrinfo(name, NULL, &hints, &res);
 178         if (error)
 179                 return NULL;
 180         else
 181                 return res;
 182 }
 183
 184 /*
 185  *  Convert net name to internet address.
 186  *  Return 0 upon failure.
 187  *  XXX - not guaranteed to be thread-safe!  See below for platforms
 188  *  on which it is thread-safe and on which it isn't.
 189  */
 190 #if defined(_WIN32) || defined(__CYGWIN__)
 191 bpf_u_int32
 192 pcap_nametonetaddr(const char *name _U_)
 193 {
 194         /*
 195          * There's no "getnetbyname()" on Windows.
 196          *
 197          * XXX - I guess we could use the BSD code to read
 198          * C:\Windows\System32\drivers\etc/networks, assuming
 199          * that's its home on all the versions of Windows
 200          * we use, but that file probably just has the loopback
 201          * network on 127/24 on 99 44/100% of Windows machines.
 202          *
 203          * (Heck, these days it probably just has that on 99 44/100%
 204          * of *UN*X* machines.)
 205          */
 206         return 0;
 207 }
 208 #else /* _WIN32 */
 209 bpf_u_int32
 210 pcap_nametonetaddr(const char *name)
 211 {
 212         /*
 213          * UN*X.
 214          */
 215         struct netent *np;
 216   #if defined(HAVE_LINUX_GETNETBYNAME_R)
 217         /*
 218          * We have Linux's reentrant getnetbyname_r().
 219          */
 220         struct netent result_buf;
 221         char buf[1024]; /* arbitrary size */
 222         int h_errnoval;
 223         int err;
 224
 225         /*
 226          * Apparently, the man page at
 227          *
 228          *    http://man7.org/linux/man-pages/man3/getnetbyname_r.3.html
 229          *
 230          * lies when it says
 231          *
 232          *    If the function call successfully obtains a network record,
 233          *    then *result is set pointing to result_buf; otherwise, *result
 234          *    is set to NULL.
 235          *
 236          * and, in fact, at least in some versions of GNU libc, it does
 237          * *not* always get set if getnetbyname_r() succeeds.
 238          */
 239         np = NULL;
 240         err = getnetbyname_r(name, &result_buf, buf, sizeof buf, &np,
 241             &h_errnoval);
 242         if (err != 0) {
 243                 /*
 244                  * XXX - dynamically allocate the buffer, and make it
 245                  * bigger if we get ERANGE back?
 246                  */
 247                 return 0;
 248         }
 249   #elif defined(HAVE_SOLARIS_GETNETBYNAME_R)
 250         /*
 251          * We have Solaris's reentrant getnetbyname_r().
 252          */
 253         struct netent result_buf;
 254         char buf[1024]; /* arbitrary size */
 255
 256         np = getnetbyname_r(name, &result_buf, buf, (int)sizeof buf);
 257   #elif defined(HAVE_AIX_GETNETBYNAME_R)
 258         /*
 259          * We have AIX's reentrant getnetbyname_r().
 260          */
 261         struct netent result_buf;
 262         struct netent_data net_data;
 263
 264         if (getnetbyname_r(name, &result_buf, &net_data) == -1)
 265                 np = NULL;
 266         else
 267                 np = &result_buf;
 268   #else
 269         /*
 270          * We don't have any getnetbyname_r(); either we have a
 271          * getnetbyname() that uses thread-specific data, in which
 272          * case we're thread-safe (sufficiently recent FreeBSD,
 273          * sufficiently recent Darwin-based OS, sufficiently recent
 274          * HP-UX, or we have the
 275          * traditional getnetbyname() (everything else, including
 276          * current NetBSD and OpenBSD), in which case we're not
 277          * thread-safe.
 278          */
 279         np = getnetbyname(name);
 280   #endif
 281         if (np != NULL)
 282                 return np->n_net;
 283         else
 284                 return 0;
 285 }
 286 #endif /* _WIN32 */
 287
 288 /*
 289  * Convert a port name to its port and protocol numbers.
 290  * We assume only TCP or UDP.
 291  * Return 0 upon failure.
 292  */
 293 int
 294 pcap_nametoport(const char *name, int *port, int *proto)
 295 {
 296         struct addrinfo hints, *res, *ai;
 297         int error;
 298         struct sockaddr_in *in4;
 299 #ifdef INET6
 300         struct sockaddr_in6 *in6;
 301 #endif
 302         int tcp_port = -1;
 303         int udp_port = -1;
 304
 305         /*
 306          * We check for both TCP and UDP in case there are
 307          * ambiguous entries.
 308          */
 309         memset(&hints, 0, sizeof(hints));
 310         hints.ai_family = PF_UNSPEC;
 311         hints.ai_socktype = SOCK_STREAM;
 312         hints.ai_protocol = IPPROTO_TCP;
 313         error = getaddrinfo(NULL, name, &hints, &res);
 314         if (error != 0) {
 315                 if (error != EAI_NONAME &&
 316                     error != EAI_SERVICE) {
 317                         /*
 318                          * This is a real error, not just "there's
 319                          * no such service name".
 320                          * XXX - this doesn't return an error string.
 321                          */
 322                         return 0;
 323                 }
 324         } else {
 325                 /*
 326                  * OK, we found it.  Did it find anything?
 327                  */
 328                 for (ai = res; ai != NULL; ai = ai->ai_next) {
 329                         /*
 330                          * Does it have an address?
 331                          */
 332                         if (ai->ai_addr != NULL) {
 333                                 /*
 334                                  * Yes.  Get a port number; we're done.
 335                                  */
 336                                 if (ai->ai_addr->sa_family == AF_INET) {
 337                                         in4 = (struct sockaddr_in *)ai->ai_addr;
 338                                         tcp_port = ntohs(in4->sin_port);
 339                                         break;
 340                                 }
 341 #ifdef INET6
 342                                 if (ai->ai_addr->sa_family == AF_INET6) {
 343                                         in6 = (struct sockaddr_in6 *)ai->ai_addr;
 344                                         tcp_port = ntohs(in6->sin6_port);
 345                                         break;
 346                                 }
 347 #endif
 348                         }
 349                 }
 350                 freeaddrinfo(res);
 351         }
 352
 353         memset(&hints, 0, sizeof(hints));
 354         hints.ai_family = PF_UNSPEC;
 355         hints.ai_socktype = SOCK_DGRAM;
 356         hints.ai_protocol = IPPROTO_UDP;
 357         error = getaddrinfo(NULL, name, &hints, &res);
 358         if (error != 0) {
 359                 if (error != EAI_NONAME &&
 360                     error != EAI_SERVICE) {
 361                         /*
 362                          * This is a real error, not just "there's
 363                          * no such service name".
 364                          * XXX - this doesn't return an error string.
 365                          */
 366                         return 0;
 367                 }
 368         } else {
 369                 /*
 370                  * OK, we found it.  Did it find anything?
 371                  */
 372                 for (ai = res; ai != NULL; ai = ai->ai_next) {
 373                         /*
 374                          * Does it have an address?
 375                          */
 376                         if (ai->ai_addr != NULL) {
 377                                 /*
 378                                  * Yes.  Get a port number; we're done.
 379                                  */
 380                                 if (ai->ai_addr->sa_family == AF_INET) {
 381                                         in4 = (struct sockaddr_in *)ai->ai_addr;
 382                                         udp_port = ntohs(in4->sin_port);
 383                                         break;
 384                                 }
 385 #ifdef INET6
 386                                 if (ai->ai_addr->sa_family == AF_INET6) {
 387                                         in6 = (struct sockaddr_in6 *)ai->ai_addr;
 388                                         udp_port = ntohs(in6->sin6_port);
 389                                         break;
 390                                 }
 391 #endif
 392                         }
 393                 }
 394                 freeaddrinfo(res);
 395         }
 396
 397         /*
 398          * We need to check /etc/services for ambiguous entries.
 399          * If we find an ambiguous entry, and it has the
 400          * same port number, change the proto to PROTO_UNDEF
 401          * so both TCP and UDP will be checked.
 402          */
 403         if (tcp_port >= 0) {
 404                 *port = tcp_port;
 405                 *proto = IPPROTO_TCP;
 406                 if (udp_port >= 0) {
 407                         if (udp_port == tcp_port)
 408                                 *proto = PROTO_UNDEF;
 409 #ifdef notdef
 410                         else
 411                                 /* Can't handle ambiguous names that refer
 412                                    to different port numbers. */
 413                                 warning("ambiguous port %s in /etc/services",
 414                                         name);
 415 #endif
 416                 }
 417                 return 1;
 418         }
 419         if (udp_port >= 0) {
 420                 *port = udp_port;
 421                 *proto = IPPROTO_UDP;
 422                 return 1;
 423         }
 424         return 0;
 425 }
 426
 427 /*
 428  * Convert a string in the form PPP-PPP, where correspond to ports, to
 429  * a starting and ending port in a port range.
 430  * Return 0 on failure.
 431  */
 432 int
 433 pcap_nametoportrange(const char *name, int *port1, int *port2, int *proto)
 434 {
 435         char *off, *cpy;
 436         int save_proto;
 437
 438         if ((cpy = strdup(name)) == NULL)
 439                 return 0;
 440
 441         if ((off = strchr(cpy, '-')) == NULL) {
 442                 free(cpy);
 443                 return 0;
 444         }
 445
 446         *off = '\0';
 447
 448         if (pcap_nametoport(cpy, port1, proto) == 0) {
 449                 free(cpy);
 450                 return 0;
 451         }
 452         save_proto = *proto;
 453
 454         if (pcap_nametoport(off + 1, port2, proto) == 0) {
 455                 free(cpy);
 456                 return 0;
 457         }
 458         free(cpy);
 459
 460         if (*proto != save_proto)
 461                 *proto = PROTO_UNDEF;
 462
 463         return 1;
 464 }
 465
 466 /*
 467  * XXX - not guaranteed to be thread-safe!  See below for platforms
 468  * on which it is thread-safe and on which it isn't.
 469  */
 470 int
 471 pcap_nametoproto(const char *str)
 472 {
 473         struct protoent *p;
 474   #if defined(HAVE_LINUX_GETPROTOBYNAME_R)
 475         /*
 476          * We have Linux's reentrant getprotobyname_r().
 477          */
 478         struct protoent result_buf;
 479         char buf[1024]; /* arbitrary size */
 480         int err;
 481
 482         err = getprotobyname_r(str, &result_buf, buf, sizeof buf, &p);
 483         if (err != 0) {
 484                 /*
 485                  * XXX - dynamically allocate the buffer, and make it
 486                  * bigger if we get ERANGE back?
 487                  */
 488                 return 0;
 489         }
 490   #elif defined(HAVE_SOLARIS_GETPROTOBYNAME_R)
 491         /*
 492          * We have Solaris's reentrant getprotobyname_r().
 493          */
 494         struct protoent result_buf;
 495         char buf[1024]; /* arbitrary size */
 496
 497         p = getprotobyname_r(str, &result_buf, buf, (int)sizeof buf);
 498   #elif defined(HAVE_AIX_GETPROTOBYNAME_R)
 499         /*
 500          * We have AIX's reentrant getprotobyname_r().
 501          */
 502         struct protoent result_buf;
 503         // "The structure must be zero-filled before it is used..." (OpenBSD).
 504         struct protoent_data proto_data = {0};
 505
 506         if (getprotobyname_r(str, &result_buf, &proto_data) == -1)
 507                 p = NULL;
 508         else
 509                 p = &result_buf;
 510   #else
 511         /*
 512          * We don't have any getprotobyname_r(); either we have a
 513          * getprotobyname() that uses thread-specific data, in which
 514          * case we're thread-safe (sufficiently recent FreeBSD,
 515          * sufficiently recent Darwin-based OS, sufficiently recent
 516          * HP-UX, Windows), or we have
 517          * the traditional getprotobyname() (everything else, including
 518          * current NetBSD and OpenBSD), in which case we're not
 519          * thread-safe.
 520          */
 521         p = getprotobyname(str);
 522   #endif
 523         if (p != 0)
 524                 return p->p_proto;
 525         else
 526                 return PROTO_UNDEF;
 527 }
 528
 529 #include "ethertype.h"
 530
 531 struct eproto {
 532         const char *s;
 533         u_short p;
 534 };
 535
 536 /*
 537  * Static data base of ether protocol types.
 538  * tcpdump used to import this, and it's declared as an export on
 539  * Debian, at least, so make it a public symbol, even though we
 540  * don't officially export it by declaring it in a header file.
 541  * (Programs *should* do this themselves, as tcpdump now does.)
 542  *
 543  * We declare it here, right before defining it, to squelch any
 544  * warnings we might get from compilers about the lack of a
 545  * declaration.
 546  */
 547 PCAP_API struct eproto eproto_db[];
 548 PCAP_API_DEF struct eproto eproto_db[] = {
 549         { "aarp", ETHERTYPE_AARP },
 550         { "arp", ETHERTYPE_ARP },
 551         { "atalk", ETHERTYPE_ATALK },
 552         { "decnet", ETHERTYPE_DN },
 553         { "ip", ETHERTYPE_IP },
 554 #ifdef INET6
 555         { "ip6", ETHERTYPE_IPV6 },
 556 #endif
 557         { "lat", ETHERTYPE_LAT },
 558         { "loopback", ETHERTYPE_LOOPBACK },
 559         { "mopdl", ETHERTYPE_MOPDL },
 560         { "moprc", ETHERTYPE_MOPRC },
 561         { "rarp", ETHERTYPE_REVARP },
 562         { "sca", ETHERTYPE_SCA },
 563         { (char *)0, 0 }
 564 };
 565
 566 int
 567 pcap_nametoeproto(const char *s)
 568 {
 569         struct eproto *p = eproto_db;
 570
 571         while (p->s != 0) {
 572                 if (strcmp(p->s, s) == 0)
 573                         return p->p;
 574                 p += 1;
 575         }
 576         return PROTO_UNDEF;
 577 }
 578
 579 #include "llc.h"
 580
 581 /* Static data base of LLC values. */
 582 static struct eproto llc_db[] = {
 583         { "iso", LLCSAP_ISONS },
 584         { "stp", LLCSAP_8021D },
 585         { "ipx", LLCSAP_IPX },
 586         { "netbeui", LLCSAP_NETBEUI },
 587         { (char *)0, 0 }
 588 };
 589
 590 int
 591 pcap_nametollc(const char *s)
 592 {
 593         struct eproto *p = llc_db;
 594
 595         while (p->s != 0) {
 596                 if (strcmp(p->s, s) == 0)
 597                         return p->p;
 598                 p += 1;
 599         }
 600         return PROTO_UNDEF;
 601 }
 602
 603 /* Hex digit to 8-bit unsigned integer. */
 604 u_char
 605 pcapint_xdtoi(const u_char c)
 606 {
 607         if (c >= '0' && c <= '9')
 608                 return (u_char)(c - '0');
 609         else if (c >= 'a' && c <= 'f')
 610                 return (u_char)(c - 'a' + 10);
 611         else
 612                 return (u_char)(c - 'A' + 10);
 613 }
 614
 615 int
 616 pcapint_atoin(const char *s, bpf_u_int32 *addr)
 617 {
 618         u_int n;
 619         int len;
 620
 621         *addr = 0;
 622         len = 0;
 623         for (;;) {
 624                 n = 0;
 625                 while (*s && *s != '.') {
 626                         if (n > 25) {
 627                                 /* The result will be > 255 */
 628                                 return -1;
 629                         }
 630                         n = n * 10 + *s++ - '0';
 631                 }
 632                 if (n > 255)
 633                         return -1;
 634                 *addr <<= 8;
 635                 *addr |= n & 0xff;
 636                 len += 8;
 637                 if (*s == '\0')
 638                         return len;
 639                 ++s;
 640         }
 641         /* NOTREACHED */
 642 }
 643
 644 /*
 645  * If 's' is not a string that is a well-formed DECnet address (aa.nnnn),
 646  * return zero.  Otherwise parse the address into the low 16 bits of 'addr'
 647  * and return a non-zero.  The binary DECnet address consists of a 6-bit area
 648  * number and a 10-bit node number; neither area 0 nor node 0 are valid for
 649  * normal addressing purposes, but either can appear on the wire.
 650  */
 651 int
 652 pcapint_atodn(const char *s, bpf_u_int32 *addr)
 653 {
 654 #define AREASHIFT 10
 655 #define AREAMASK 0176000
 656 #define NODEMASK 01777
 657
 658         /* Initialize to squelch a compiler warning only. */
 659         u_int node = 0, area = 0;
 660         /*
 661          *               +--+             +--+
 662          *               |  |             |  |
 663          *               v  |             v  |
 664          * --> START --> AREA --> DOT --> NODE -->
 665          *       |          |     |        |
 666          *       |          v     v        |
 667          *       +--------> INVALID <------+
 668          */
 669         enum {
 670                 START,
 671                 AREA,
 672                 DOT,
 673                 NODE,
 674                 INVALID
 675         } fsm_state = START;
 676
 677         while (*s) {
 678                 switch (fsm_state) {
 679                 case START:
 680                         if (PCAP_ISDIGIT(*s)) {
 681                                 area = *s - '0';
 682                                 fsm_state = AREA;
 683                                 break;
 684                         }
 685                         fsm_state = INVALID;
 686                         break;
 687                 case AREA:
 688                         if (*s == '.') {
 689                                 fsm_state = DOT;
 690                                 break;
 691                         }
 692                         if (PCAP_ISDIGIT(*s)) {
 693                                 area = area * 10 + *s - '0';
 694                                 if (area <= AREAMASK >> AREASHIFT)
 695                                         break;
 696                         }
 697                         fsm_state = INVALID;
 698                         break;
 699                 case DOT:
 700                         if (PCAP_ISDIGIT(*s)) {
 701                                 node = *s - '0';
 702                                 fsm_state = NODE;
 703                                 break;
 704                         }
 705                         fsm_state = INVALID;
 706                         break;
 707                 case NODE:
 708                         if (PCAP_ISDIGIT(*s)) {
 709                                 node = node * 10 + *s - '0';
 710                                 if (node <= NODEMASK)
 711                                         break;
 712                         }
 713                         fsm_state = INVALID;
 714                         break;
 715                 case INVALID:
 716                         return 0;
 717                 } /* switch */
 718                 s++;
 719         } /* while */
 720         /*
 721          * This condition is false if the string comes from the lexer, but
 722          * let's not depend on that.
 723          */
 724         if (fsm_state != NODE)
 725                 return 0;
 726
 727         *addr = area << AREASHIFT | node;
 728         return(32);
 729 }
 730
 731 /*
 732  * libpcap ARCnet address format is "^\$[0-9a-fA-F]{1,2}$" in regexp syntax.
 733  * Iff the given string is a well-formed ARCnet address, parse the string,
 734  * store the 8-bit unsigned value into the provided integer and return 1.
 735  * Otherwise return 0.
 736  *
 737  *  --> START -- $ --> DOLLAR -- [0-9a-fA-F] --> HEX1 -- \0 -->-+
 738  *        |              |                        |             |
 739  *       [.]            [.]                  [0-9a-fA-F]        |
 740  *        |              |                        |             |
 741  *        v              v                        v             v
 742  *    (invalid) <--------+-<---------------[.]-- HEX2 -- \0 -->-+--> (valid)
 743  */
 744 int
 745 pcapint_atoan(const char *s, uint8_t *addr)
 746 {
 747         enum {
 748                 START,
 749                 DOLLAR,
 750                 HEX1,
 751                 HEX2,
 752         } fsm_state = START;
 753         uint8_t tmp = 0;
 754
 755         while (*s) {
 756                 switch (fsm_state) {
 757                 case START:
 758                         if (*s != '$')
 759                                 goto invalid;
 760                         fsm_state = DOLLAR;
 761                         break;
 762                 case DOLLAR:
 763                         if (! PCAP_ISXDIGIT(*s))
 764                                 goto invalid;
 765                         tmp = pcapint_xdtoi(*s);
 766                         fsm_state = HEX1;
 767                         break;
 768                 case HEX1:
 769                         if (! PCAP_ISXDIGIT(*s))
 770                                 goto invalid;
 771                         tmp <<= 4;
 772                         tmp |= pcapint_xdtoi(*s);
 773                         fsm_state = HEX2;
 774                         break;
 775                 case HEX2:
 776                         goto invalid;
 777                 } // switch
 778                 s++;
 779         } // while
 780         if (fsm_state == HEX1 || fsm_state == HEX2) {
 781                 *addr = tmp;
 782                 return 1;
 783         }
 784
 785 invalid:
 786         return 0;
 787 }
 788
 789 /*
 790  * Convert 's', which can have the one of the forms:
 791  *
 792  *      "xx:xx:xx:xx:xx:xx"
 793  *      "xx.xx.xx.xx.xx.xx"
 794  *      "xx-xx-xx-xx-xx-xx"
 795  *      "xxxx.xxxx.xxxx"
 796  *      "xxxxxxxxxxxx"
 797  *
 798  * (or various mixes of ':', '.', and '-') into a new
 799  * ethernet address.  Assumes 's' is well formed.
 800  */
 801 u_char *
 802 pcap_ether_aton(const char *s)
 803 {
 804         register u_char *ep, *e;
 805         register u_char d;
 806
 807         e = ep = (u_char *)malloc(6);
 808         if (e == NULL)
 809                 return (NULL);
 810
 811         while (*s) {
 812                 if (*s == ':' || *s == '.' || *s == '-')
 813                         s += 1;
 814                 d = pcapint_xdtoi(*s++);
 815                 if (PCAP_ISXDIGIT(*s)) {
 816                         d <<= 4;
 817                         d |= pcapint_xdtoi(*s++);
 818                 }
 819                 *ep++ = d;
 820         }
 821
 822         return (e);
 823 }
 824
 825 #ifndef HAVE_ETHER_HOSTTON
 826 /*
 827  * Roll our own.
 828  *
 829  * This should be thread-safe, as we define the static variables
 830  * we use to be thread-local, and as pcap_next_etherent() does so
 831  * as well.
 832  */
 833 u_char *
 834 pcap_ether_hostton(const char *name)
 835 {
 836         register struct pcap_etherent *ep;
 837         register u_char *ap;
 838         static thread_local FILE *fp = NULL;
 839         static thread_local int init = 0;
 840
 841         if (!init) {
 842                 fp = fopen(PCAP_ETHERS_FILE, "r");
 843                 ++init;
 844                 if (fp == NULL)
 845                         return (NULL);
 846         } else if (fp == NULL)
 847                 return (NULL);
 848         else
 849                 rewind(fp);
 850
 851         while ((ep = pcap_next_etherent(fp)) != NULL) {
 852                 if (strcmp(ep->name, name) == 0) {
 853                         ap = (u_char *)malloc(6);
 854                         if (ap != NULL) {
 855                                 memcpy(ap, ep->addr, 6);
 856                                 return (ap);
 857                         }
 858                         break;
 859                 }
 860         }
 861         return (NULL);
 862 }
 863 #else
 864 /*
 865  * Use the OS-supplied routine.
 866  * This *should* be thread-safe; the API doesn't have a static buffer.
 867  */
 868 u_char *
 869 pcap_ether_hostton(const char *name)
 870 {
 871         register u_char *ap;
 872         u_char a[6];
 873         char namebuf[1024];
 874
 875         /*
 876          * In AIX 7.1 and 7.2: int ether_hostton(char *, struct ether_addr *);
 877          */
 878         pcapint_strlcpy(namebuf, name, sizeof(namebuf));
 879         ap = NULL;
 880         if (ether_hostton(namebuf, (struct ether_addr *)a) == 0) {
 881                 ap = (u_char *)malloc(6);
 882                 if (ap != NULL)
 883                         memcpy((char *)ap, (char *)a, 6);
 884         }
 885         return (ap);
 886 }
 887 #endif