The Tcpdump Group git mirrors - libpcap/blob - scanner.l

   1 %top {
   2 /* Must come first for _LARGE_FILE_API on AIX. */
   3 #ifdef HAVE_CONFIG_H
   4 #include <config.h>
   5 #endif
   6
   7 /*
   8  * Must come first to avoid warnings on Windows.
   9  *
  10  * Flex-generated scanners may only include <inttypes.h> if __STDC_VERSION__
  11  * is defined with a value >= 199901, meaning "full C99", and MSVC may not
  12  * define it with that value, because it isn't 100% C99-compliant, even
  13  * though it has an <inttypes.h> capable of defining everything the Flex
  14  * scanner needs.
  15  *
  16  * We, however, will include it if we know we have an MSVC version that has
  17  * it; this means that we may define the INTn_MAX and UINTn_MAX values in
  18  * scanner.c, and then include <stdint.h>, which may define them differently
  19  * (same value, but different string of characters), causing compiler warnings.
  20  *
  21  * If we include it here, and they're defined, that'll prevent scanner.c
  22  * from defining them.  So we include <pcap/pcap-inttypes.h>, to get
  23  * <inttypes.h> if we have it.
  24  */
  25 #include <pcap/pcap-inttypes.h>
  26
  27 #include "diag-control.h"
  28 }
  29
  30 /*
  31  * We want a reentrant scanner.
  32  */
  33 %option reentrant
  34
  35 /*
  36  * And we need to pass the compiler state to the scanner.
  37  */
  38 %option extra-type="compiler_state_t *"
  39
  40 /*
  41  * We don't use input, so don't generate code for it.
  42  */
  43 %option noinput
  44
  45 /*
  46  * We don't use unput, so don't generate code for it.
  47  */
  48 %option nounput
  49
  50 /*
  51  * We don't read from the terminal.
  52  */
  53 %option never-interactive
  54
  55 /*
  56  * We want to stop processing when we get to the end of the input.
  57  */
  58 %option noyywrap
  59
  60 /*
  61  * We want to generate code that can be used by a reentrant parser
  62  * generated by Bison or Berkeley YACC.
  63  */
  64 %option bison-bridge
  65
  66 %{
  67 /*
  68  * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997
  69  *      The Regents of the University of California.  All rights reserved.
  70  *
  71  * Redistribution and use in source and binary forms, with or without
  72  * modification, are permitted provided that: (1) source code distributions
  73  * retain the above copyright notice and this paragraph in its entirety, (2)
  74  * distributions including binary code include the above copyright notice and
  75  * this paragraph in its entirety in the documentation or other materials
  76  * provided with the distribution, and (3) all advertising materials mentioning
  77  * features or use of this software display the following acknowledgement:
  78  * ``This product includes software developed by the University of California,
  79  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
  80  * the University nor the names of its contributors may be used to endorse
  81  * or promote products derived from this software without specific prior
  82  * written permission.
  83  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
  84  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
  85  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  86  */
  87
  88 #include <ctype.h>
  89 #include <string.h>
  90
  91 #include "pcap-int.h"
  92
  93 #include "gencode.h"
  94
  95 #include "grammar.h"
  96
  97 /*
  98  * Earlier versions of Flex don't declare these, so we declare them
  99  * ourselves to squelch warnings.
 100  */
 101 int pcap_get_column(yyscan_t);
 102 void pcap_set_column(int, yyscan_t);
 103
 104 #ifdef INET6
 105
 106 #ifdef _WIN32
 107 #include <winsock2.h>
 108 #include <ws2tcpip.h>
 109 /*
 110  * To quote the MSDN page for getaddrinfo() at
 111  *
 112  *    https://msdn.microsoft.com/en-us/library/windows/desktop/ms738520(v=vs.85).aspx
 113  *
 114  * "Support for getaddrinfo on Windows 2000 and older versions
 115  * The getaddrinfo function was added to the Ws2_32.dll on Windows XP and
 116  * later. To execute an application that uses this function on earlier
 117  * versions of Windows, then you need to include the Ws2tcpip.h and
 118  * Wspiapi.h files. When the Wspiapi.h include file is added, the
 119  * getaddrinfo function is defined to the WspiapiGetAddrInfo inline
 120  * function in the Wspiapi.h file. At runtime, the WspiapiGetAddrInfo
 121  * function is implemented in such a way that if the Ws2_32.dll or the
 122  * Wship6.dll (the file containing getaddrinfo in the IPv6 Technology
 123  * Preview for Windows 2000) does not include getaddrinfo, then a
 124  * version of getaddrinfo is implemented inline based on code in the
 125  * Wspiapi.h header file. This inline code will be used on older Windows
 126  * platforms that do not natively support the getaddrinfo function."
 127  *
 128  * We use getaddrinfo(), so we include Wspiapi.h here.
 129  */
 130 #include <wspiapi.h>
 131 #else /* _WIN32 */
 132 #include <sys/socket.h> /* for "struct sockaddr" in "struct addrinfo" */
 133 #include <netdb.h>      /* for "struct addrinfo" */
 134 #endif /* _WIN32 */
 135
 136 /* Workaround for AIX 4.3 */
 137 #if !defined(AI_NUMERICHOST)
 138 #define AI_NUMERICHOST 0x04
 139 #endif
 140
 141 #endif /*INET6*/
 142
 143 #include <pcap/namedb.h>
 144 #include "grammar.h"
 145
 146 #ifdef HAVE_OS_PROTO_H
 147 #include "os-proto.h"
 148 #endif
 149
 150 static int stou(char *, YYSTYPE *, compiler_state_t *);
 151
 152 /*
 153  * Disable diagnostics in the code generated by Flex.
 154  */
 155 DIAG_OFF_FLEX
 156
 157 %}
 158
 159 N               ([0-9]+|(0X|0x)[0-9A-Fa-f]+)
 160 B               ([0-9A-Fa-f][0-9A-Fa-f]?)
 161 B2              ([0-9A-Fa-f][0-9A-Fa-f][0-9A-Fa-f][0-9A-Fa-f])
 162 W               ([0-9A-Fa-f][0-9A-Fa-f]?[0-9A-Fa-f]?[0-9A-Fa-f]?)
 163
 164 %a 18400
 165 %o 21500
 166 %e 7600
 167 %k 4550
 168 %p 27600
 169 %n 2000
 170
 171 V680            {W}:{W}:{W}:{W}:{W}:{W}:{W}:{W}
 172
 173 V670            ::{W}:{W}:{W}:{W}:{W}:{W}:{W}
 174 V671            {W}::{W}:{W}:{W}:{W}:{W}:{W}
 175 V672            {W}:{W}::{W}:{W}:{W}:{W}:{W}
 176 V673            {W}:{W}:{W}::{W}:{W}:{W}:{W}
 177 V674            {W}:{W}:{W}:{W}::{W}:{W}:{W}
 178 V675            {W}:{W}:{W}:{W}:{W}::{W}:{W}
 179 V676            {W}:{W}:{W}:{W}:{W}:{W}::{W}
 180 V677            {W}:{W}:{W}:{W}:{W}:{W}:{W}::
 181
 182 V660            ::{W}:{W}:{W}:{W}:{W}:{W}
 183 V661            {W}::{W}:{W}:{W}:{W}:{W}
 184 V662            {W}:{W}::{W}:{W}:{W}:{W}
 185 V663            {W}:{W}:{W}::{W}:{W}:{W}
 186 V664            {W}:{W}:{W}:{W}::{W}:{W}
 187 V665            {W}:{W}:{W}:{W}:{W}::{W}
 188 V666            {W}:{W}:{W}:{W}:{W}:{W}::
 189
 190 V650            ::{W}:{W}:{W}:{W}:{W}
 191 V651            {W}::{W}:{W}:{W}:{W}
 192 V652            {W}:{W}::{W}:{W}:{W}
 193 V653            {W}:{W}:{W}::{W}:{W}
 194 V654            {W}:{W}:{W}:{W}::{W}
 195 V655            {W}:{W}:{W}:{W}:{W}::
 196
 197 V640            ::{W}:{W}:{W}:{W}
 198 V641            {W}::{W}:{W}:{W}
 199 V642            {W}:{W}::{W}:{W}
 200 V643            {W}:{W}:{W}::{W}
 201 V644            {W}:{W}:{W}:{W}::
 202
 203 V630            ::{W}:{W}:{W}
 204 V631            {W}::{W}:{W}
 205 V632            {W}:{W}::{W}
 206 V633            {W}:{W}:{W}::
 207
 208 V620            ::{W}:{W}
 209 V621            {W}::{W}
 210 V622            {W}:{W}::
 211
 212 V610            ::{W}
 213 V611            {W}::
 214
 215 V600            ::
 216
 217 V6604           {W}:{W}:{W}:{W}:{W}:{W}:{N}\.{N}\.{N}\.{N}
 218
 219 V6504           ::{W}:{W}:{W}:{W}:{W}:{N}\.{N}\.{N}\.{N}
 220 V6514           {W}::{W}:{W}:{W}:{W}:{N}\.{N}\.{N}\.{N}
 221 V6524           {W}:{W}::{W}:{W}:{W}:{N}\.{N}\.{N}\.{N}
 222 V6534           {W}:{W}:{W}::{W}:{W}:{N}\.{N}\.{N}\.{N}
 223 V6544           {W}:{W}:{W}:{W}::{W}:{N}\.{N}\.{N}\.{N}
 224 V6554           {W}:{W}:{W}:{W}:{W}::{N}\.{N}\.{N}\.{N}
 225
 226 V6404           ::{W}:{W}:{W}:{W}:{N}\.{N}\.{N}\.{N}
 227 V6414           {W}::{W}:{W}:{W}:{N}\.{N}\.{N}\.{N}
 228 V6424           {W}:{W}::{W}:{W}:{N}\.{N}\.{N}\.{N}
 229 V6434           {W}:{W}:{W}::{W}:{N}\.{N}\.{N}\.{N}
 230 V6444           {W}:{W}:{W}:{W}::{N}\.{N}\.{N}\.{N}
 231
 232 V6304           ::{W}:{W}:{W}:{N}\.{N}\.{N}\.{N}
 233 V6314           {W}::{W}:{W}:{N}\.{N}\.{N}\.{N}
 234 V6324           {W}:{W}::{W}:{N}\.{N}\.{N}\.{N}
 235 V6334           {W}:{W}:{W}::{N}\.{N}\.{N}\.{N}
 236
 237 V6204           ::{W}:{W}:{N}\.{N}\.{N}\.{N}
 238 V6214           {W}::{W}:{N}\.{N}\.{N}\.{N}
 239 V6224           {W}:{W}::{N}\.{N}\.{N}\.{N}
 240
 241 V6104           ::{W}:{N}\.{N}\.{N}\.{N}
 242 V6114           {W}::{N}\.{N}\.{N}\.{N}
 243
 244 V6004           ::{N}\.{N}\.{N}\.{N}
 245
 246
 247 V6              ({V680}|{V670}|{V671}|{V672}|{V673}|{V674}|{V675}|{V676}|{V677}|{V660}|{V661}|{V662}|{V663}|{V664}|{V665}|{V666}|{V650}|{V651}|{V652}|{V653}|{V654}|{V655}|{V640}|{V641}|{V642}|{V643}|{V644}|{V630}|{V631}|{V632}|{V633}|{V620}|{V621}|{V622}|{V610}|{V611}|{V600}|{V6604}|{V6504}|{V6514}|{V6524}|{V6534}|{V6544}|{V6554}|{V6404}|{V6414}|{V6424}|{V6434}|{V6444}|{V6304}|{V6314}|{V6324}|{V6334}|{V6204}|{V6214}|{V6224}|{V6104}|{V6114}|{V6004})
 248
 249 MAC             ({B}:{B}:{B}:{B}:{B}:{B}|{B}\-{B}\-{B}\-{B}\-{B}\-{B}|{B}\.{B}\.{B}\.{B}\.{B}\.{B}|{B2}\.{B2}\.{B2}|{B2}{3})
 250
 251
 252
 253 %%
 254 dst             return DST;
 255 src             return SRC;
 256
 257 link|ether|ppp|slip  return LINK;
 258 fddi|tr|wlan    return LINK;
 259 arp             return ARP;
 260 rarp            return RARP;
 261 ip              return IP;
 262 sctp            return SCTP;
 263 tcp             return TCP;
 264 udp             return UDP;
 265 icmp            return ICMP;
 266 igmp            return IGMP;
 267 igrp            return IGRP;
 268 pim             return PIM;
 269 vrrp            return VRRP;
 270 carp            return CARP;
 271 radio           return RADIO;
 272
 273 ip6             return IPV6;
 274 icmp6           return ICMPV6;
 275 ah              return AH;
 276 esp             return ESP;
 277
 278 atalk           return ATALK;
 279 aarp            return AARP;
 280 decnet          return DECNET;
 281 lat             return LAT;
 282 sca             return SCA;
 283 moprc           return MOPRC;
 284 mopdl           return MOPDL;
 285
 286 iso             return ISO;
 287 esis            return ESIS;
 288 es-is           return ESIS;
 289 isis            return ISIS;
 290 is-is           return ISIS;
 291 l1              return L1;
 292 l2              return L2;
 293 iih             return IIH;
 294 lsp             return LSP;
 295 snp             return SNP;
 296 csnp            return CSNP;
 297 psnp            return PSNP;
 298
 299 clnp            return CLNP;
 300
 301 stp             return STP;
 302
 303 ipx             return IPX;
 304
 305 netbeui         return NETBEUI;
 306
 307 host            return HOST;
 308 net             return NET;
 309 mask            return NETMASK;
 310 port            return PORT;
 311 portrange       return PORTRANGE;
 312 proto           return PROTO;
 313 protochain      return PROTOCHAIN;
 314
 315 gateway         return GATEWAY;
 316
 317 type            return TYPE;
 318 subtype         return SUBTYPE;
 319 direction|dir   return DIR;
 320 address1|addr1  return ADDR1;
 321 address2|addr2  return ADDR2;
 322 address3|addr3  return ADDR3;
 323 address4|addr4  return ADDR4;
 324 ra              return RA;
 325 ta              return TA;
 326
 327 less            return LESS;
 328 greater         return GREATER;
 329 byte            return CBYTE;
 330 broadcast       return TK_BROADCAST;
 331 multicast       return TK_MULTICAST;
 332
 333 and|"&&"        return AND;
 334 or|"||"         return OR;
 335 not             return '!';
 336
 337 len|length      return LEN;
 338 inbound         return INBOUND;
 339 outbound        return OUTBOUND;
 340
 341 vlan            return VLAN;
 342 mpls            return MPLS;
 343 pppoed          return PPPOED;
 344 pppoes          return PPPOES;
 345 geneve          return GENEVE;
 346
 347 lane            return LANE;
 348 llc             return LLC;
 349 metac           return METAC;
 350 bcc             return BCC;
 351 oam             return OAM;
 352 oamf4           return OAMF4;
 353 oamf4ec         return OAMF4EC;
 354 oamf4sc         return OAMF4SC;
 355 sc              return SC;
 356 ilmic           return ILMIC;
 357 vpi             return VPI;
 358 vci             return VCI;
 359 connectmsg      return CONNECTMSG;
 360 metaconnect     return METACONNECT;
 361
 362 on|ifname       return PF_IFNAME;
 363 rset|ruleset    return PF_RSET;
 364 rnr|rulenum     return PF_RNR;
 365 srnr|subrulenum return PF_SRNR;
 366 reason          return PF_REASON;
 367 action          return PF_ACTION;
 368
 369 fisu            return FISU;
 370 lssu            return LSSU;
 371 lsu             return LSSU;
 372 msu             return MSU;
 373 hfisu           return HFISU;
 374 hlssu           return HLSSU;
 375 hmsu            return HMSU;
 376 sio             return SIO;
 377 opc             return OPC;
 378 dpc             return DPC;
 379 sls             return SLS;
 380 hsio            return HSIO;
 381 hopc            return HOPC;
 382 hdpc            return HDPC;
 383 hsls            return HSLS;
 384
 385 [ \r\n\t]               ;
 386 [+\-*/%:\[\]!<>()&|\^=] return yytext[0];
 387 ">="                    return GEQ;
 388 "<="                    return LEQ;
 389 "!="                    return NEQ;
 390 "=="                    return '=';
 391 "<<"                    return LSH;
 392 ">>"                    return RSH;
 393 ${B}                    { yylval->s = sdup(yyextra, yytext); return AID; }
 394 {MAC}                   { yylval->s = sdup(yyextra, yytext); return EID; }
 395 {N}                     { return stou(yytext, yylval, yyextra); }
 396 ({N}\.{N})|({N}\.{N}\.{N})|({N}\.{N}\.{N}\.{N}) {
 397                         yylval->s = sdup(yyextra, (char *)yytext); return HID; }
 398 {V6}                    {
 399 #ifdef INET6
 400                           struct addrinfo hints, *res;
 401                           memset(&hints, 0, sizeof(hints));
 402                           hints.ai_family = AF_INET6;
 403                           hints.ai_flags = AI_NUMERICHOST;
 404                           if (getaddrinfo(yytext, NULL, &hints, &res)) {
 405                                 bpf_set_error(yyextra, "bogus IPv6 address %s", yytext);
 406                                 yylval->s = NULL;
 407                           } else {
 408                                 freeaddrinfo(res);
 409                                 yylval->s = sdup(yyextra, (char *)yytext);
 410                           }
 411 #else
 412                           bpf_set_error(yyextra, "IPv6 address %s not supported", yytext);
 413                           yylval->s = NULL;
 414 #endif /*INET6*/
 415                           return HID6;
 416                         }
 417 {B}:+({B}:+)+           { bpf_set_error(yyextra, "bogus ethernet address %s", yytext); yylval->s = NULL; return EID; }
 418 icmptype                { yylval->h = 0; return NUM; }
 419 icmpcode                { yylval->h = 1; return NUM; }
 420 icmp-echoreply          { yylval->h = 0; return NUM; }
 421 icmp-unreach            { yylval->h = 3; return NUM; }
 422 icmp-sourcequench       { yylval->h = 4; return NUM; }
 423 icmp-redirect           { yylval->h = 5; return NUM; }
 424 icmp-echo               { yylval->h = 8; return NUM; }
 425 icmp-routeradvert       { yylval->h = 9; return NUM; }
 426 icmp-routersolicit      { yylval->h = 10; return NUM; }
 427 icmp-timxceed           { yylval->h = 11; return NUM; }
 428 icmp-paramprob          { yylval->h = 12; return NUM; }
 429 icmp-tstamp             { yylval->h = 13; return NUM; }
 430 icmp-tstampreply        { yylval->h = 14; return NUM; }
 431 icmp-ireq               { yylval->h = 15; return NUM; }
 432 icmp-ireqreply          { yylval->h = 16; return NUM; }
 433 icmp-maskreq            { yylval->h = 17; return NUM; }
 434 icmp-maskreply          { yylval->h = 18; return NUM; }
 435
 436 icmp6type       { yylval->h = 0; return NUM; }
 437 icmp6code       { yylval->h = 1; return NUM; }
 438
 439 icmp6-echo      { yylval->h = 128; return NUM; }
 440 icmp6-echoreply { yylval->h = 129; return NUM; }
 441 icmp6-multicastlistenerquery    { yylval->h = 130; return NUM; }
 442 icmp6-multicastlistenerreportv1 { yylval->h = 131; return NUM; }
 443 icmp6-multicastlistenerdone     { yylval->h = 132; return NUM; }
 444 icmp6-routersolicit   { yylval->h = 133; return NUM; }
 445 icmp6-routeradvert    { yylval->h = 134; return NUM; }
 446 icmp6-neighborsolicit { yylval->h = 135; return NUM; }
 447 icmp6-neighboradvert  { yylval->h = 136; return NUM; }
 448 icmp6-redirect    { yylval->h = 137; return NUM; }
 449 icmp6-routerrenum { yylval->h = 138; return NUM; }
 450 icmp6-nodeinformationquery      { yylval->h = 139; return NUM; }
 451 icmp6-nodeinformationresponse   { yylval->h = 140; return NUM; }
 452 icmp6-ineighbordiscoverysolicit { yylval->h = 141; return NUM; }
 453 icmp6-ineighbordiscoveryadvert  { yylval->h = 142; return NUM; }
 454 icmp6-multicastlistenerreportv2 { yylval->h = 143; return NUM; }
 455 icmp6-homeagentdiscoveryrequest { yylval->h = 144; return NUM; }
 456 icmp6-homeagentdiscoveryreply   { yylval->h = 145; return NUM; }
 457 icmp6-mobileprefixsolicit       { yylval->h = 146; return NUM; }
 458 icmp6-mobileprefixadvert        { yylval->h = 147; return NUM; }
 459 icmp6-certpathsolicit           { yylval->h = 148; return NUM; }
 460 icmp6-certpathadvert            { yylval->h = 149; return NUM; }
 461 icmp6-multicastrouteradvert     { yylval->h = 151; return NUM; }
 462 icmp6-multicastroutersolicit    { yylval->h = 152; return NUM; }
 463 icmp6-multicastrouterterm       { yylval->h = 153; return NUM; }
 464
 465 tcpflags                { yylval->h = 13; return NUM; }
 466 tcp-fin                 { yylval->h = 0x01; return NUM; }
 467 tcp-syn                 { yylval->h = 0x02; return NUM; }
 468 tcp-rst                 { yylval->h = 0x04; return NUM; }
 469 tcp-push                { yylval->h = 0x08; return NUM; }
 470 tcp-ack                 { yylval->h = 0x10; return NUM; }
 471 tcp-urg                 { yylval->h = 0x20; return NUM; }
 472 tcp-ece                 { yylval->h = 0x40; return NUM; }
 473 tcp-cwr                 { yylval->h = 0x80; return NUM; }
 474 [A-Za-z0-9]([-_.A-Za-z0-9]*[.A-Za-z0-9])? {
 475                          yylval->s = sdup(yyextra, (char *)yytext); return ID; }
 476 "\\"[^ !()\n\t]+        { yylval->s = sdup(yyextra, (char *)yytext + 1); return ID; }
 477 .                       { return LEX_ERROR; }
 478 %%
 479
 480 /*
 481  * Turn diagnostics back on, so we check the code that we've written.
 482  */
 483 DIAG_ON_FLEX
 484
 485 /*
 486  * Convert string to 32-bit unsigned integer.  Just like atoi(), but checks for
 487  * preceding 0x or 0 and uses hex or octal instead of decimal.
 488  *
 489  * On success, sets yylval->h to the value and returns NUM.
 490  * On failure, sets the BPF error string and returns LEX_ERROR, to force
 491  * the parse to stop.
 492  */
 493 static int
 494 stou(char *yytext_arg, YYSTYPE *yylval_arg, compiler_state_t *yyextra_arg)
 495 {
 496         bpf_u_int32 n = 0;
 497         unsigned int digit;
 498         char *s = yytext_arg;
 499
 500         /*
 501          * yytext_arg is guaranteed either to be a string of decimal digits
 502          * or 0[xX] followed by a string of hex digits.
 503          */
 504         if (*s == '0') {
 505                 if (s[1] == 'x' || s[1] == 'X') {
 506                         /*
 507                          * Begins with 0x or 0X, so hex.
 508                          * Guaranteed to be all hex digits following the
 509                          * prefix, so anything that's not 0-9 or a-f is
 510                          * A-F.
 511                          */
 512                         s += 2; /* skip the prefix */
 513                         while ((digit = *s++) != '\0') {
 514                                 if (digit >= '0' && digit <= '9')
 515                                         digit = digit - '0';
 516                                 else if (digit >= 'a' && digit <= 'f')
 517                                         digit = digit - 'a' + 10;
 518                                 else
 519                                         digit = digit - 'A' + 10;
 520
 521                                 /*
 522                                  * Check for overflow.
 523                                  */
 524                                 if (n > 0xFFFFFFFU) {
 525                                         /*
 526                                          * We have more than 28 bits of
 527                                          * number, and are about to
 528                                          * add 4 more; that won't fit
 529                                          * in 32 bits.
 530                                          */
 531                                         bpf_set_error(yyextra_arg,
 532                                             "number %s overflows 32 bits",
 533                                             yytext_arg);
 534                                         return LEX_ERROR;
 535                                 }
 536                                 n = (n << 4) + digit;
 537                         }
 538                 } else {
 539                         /*
 540                          * Begins with 0, but not 0x or 0X, so octal.
 541                          * Guaranteed to be all *decimal* digits following
 542                          * the prefix, so we need to catch 8 and 9 and
 543                          * report an error.
 544                          */
 545                         s += 1;
 546                         while ((digit = *s++) != '\0') {
 547                                 if (digit >= '0' && digit <= '7')
 548                                         digit = digit - '0';
 549                                 else {
 550                                         bpf_set_error(yyextra_arg,
 551                                             "number %s contains non-octal digit",
 552                                             yytext_arg);
 553                                         return LEX_ERROR;
 554                                 }
 555                                 if (n > 03777777777U) {
 556                                         /*
 557                                          * We have more than 29 bits of
 558                                          * number, and are about to add
 559                                          * 3 more; that won't fit in
 560                                          * 32 bits.
 561                                          */
 562                                         bpf_set_error(yyextra_arg,
 563                                             "number %s overflows 32 bits",
 564                                             yytext_arg);
 565                                         return LEX_ERROR;
 566                                 }
 567                                 n = (n << 3) + digit;
 568                         }
 569                 }
 570         } else {
 571                 /*
 572                  * Decimal.
 573                  */
 574                 while ((digit = *s++) != '\0') {
 575                         digit = digit - '0';
 576 #define CUTOFF_DEC      (0xFFFFFFFFU / 10U)
 577 #define CUTLIM_DEC      (0xFFFFFFFFU % 10U)
 578                         if (n > CUTOFF_DEC ||
 579                             (n == CUTOFF_DEC && digit > CUTLIM_DEC)) {
 580                                 bpf_set_error(yyextra_arg,
 581                                     "number %s overflows 32 bits",
 582                                     yytext_arg);
 583                                 return LEX_ERROR;
 584                         }
 585                         n = (n * 10) + digit;
 586                 }
 587         }
 588
 589         yylval_arg->h = n;
 590         return NUM;
 591 }