rtadvd.tproj/advcap.c

   1 /*
   2  * Copyright (c) 2009 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28
  29 /*      $KAME: advcap.c,v 1.5 2001/02/01 09:12:08 jinmei Exp $  */
  30
  31 /*
  32  * Copyright (c) 1983 The Regents of the University of California.
  33  * All rights reserved.
  34  *
  35  * Redistribution and use in source and binary forms, with or without
  36  * modification, are permitted provided that the following conditions
  37  * are met:
  38  * 1. Redistributions of source code must retain the above copyright
  39  *    notice, this list of conditions and the following disclaimer.
  40  * 2. Redistributions in binary form must reproduce the above copyright
  41  *    notice, this list of conditions and the following disclaimer in the
  42  *    documentation and/or other materials provided with the distribution.
  43  * 3. All advertising materials mentioning features or use of this software
  44  *    must display the following acknowledgement:
  45  *      This product includes software developed by the University of
  46  *      California, Berkeley and its contributors.
  47  * 4. Neither the name of the University nor the names of its contributors
  48  *    may be used to endorse or promote products derived from this software
  49  *    without specific prior written permission.
  50  *
  51  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  52  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  53  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  54  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  55  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  56  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  57  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  58  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  59  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  60  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  61  * SUCH DAMAGE.
  62  *
  63  * $FreeBSD: src/usr.sbin/rtadvd/advcap.c,v 1.1.2.2 2001/07/03 11:02:13 ume Exp $
  64  */
  65
  66 /*
  67  * remcap - routines for dealing with the remote host data base
  68  *
  69  * derived from termcap
  70  */
  71 #include <sys/types.h>
  72 #include <sys/uio.h>
  73 #include <unistd.h>
  74 #include <fcntl.h>
  75 #include <ctype.h>
  76 #include <stdlib.h>
  77 #include <stdio.h>
  78 #include <syslog.h>
  79 #include <errno.h>
  80 #include <string.h>
  81 #include "pathnames.h"
  82
  83 #ifndef BUFSIZ
  84 #define BUFSIZ          1024
  85 #endif
  86 #define MAXHOP          32              /* max number of tc= indirections */
  87
  88 #define tgetent         agetent
  89 #define tnchktc         anchktc
  90 #define tnamatch        anamatch
  91 #define tgetnum         agetnum
  92 #define tgetflag        agetflag
  93 #define tgetstr         agetstr
  94
  95 #if 0
  96 #define V_TERMCAP       "REMOTE"
  97 #define V_TERM          "HOST"
  98 #endif
  99
 100 char    *RM;
 101
 102 /*
 103  * termcap - routines for dealing with the terminal capability data base
 104  *
 105  * BUG:         Should use a "last" pointer in tbuf, so that searching
 106  *              for capabilities alphabetically would not be a n**2/2
 107  *              process when large numbers of capabilities are given.
 108  * Note:        If we add a last pointer now we will screw up the
 109  *              tc capability. We really should compile termcap.
 110  *
 111  * Essentially all the work here is scanning and decoding escapes
 112  * in string capabilities.  We don't use stdio because the editor
 113  * doesn't, and because living w/o it is not hard.
 114  */
 115
 116 static  char *tbuf;
 117 static  int hopcount;   /* detect infinite loops in termcap, init 0 */
 118
 119 static  char *remotefile;
 120
 121 extern char *conffile;
 122
 123 int tgetent __P((char *, char *));
 124 int getent __P((char *, char *, char *));
 125 int tnchktc __P((void));
 126 int tnamatch __P((char *));
 127 static char *tskip __P((char *));
 128 long long tgetnum __P((char *));
 129 int tgetflag __P((char *));
 130 char *tgetstr __P((char *, char **));
 131 static char *tdecode __P((char *, char **));
 132
 133 /*
 134  * Get an entry for terminal name in buffer bp,
 135  * from the termcap file.  Parse is very rudimentary;
 136  * we just notice escaped newlines.
 137  */
 138 int
 139 tgetent(bp, name)
 140         char *bp, *name;
 141 {
 142         char *cp;
 143
 144         remotefile = cp = conffile ? conffile : _PATH_RTADVDCONF;
 145         return (getent(bp, name, cp));
 146 }
 147
 148 int
 149 getent(bp, name, cp)
 150         char *bp, *name, *cp;
 151 {
 152         register int c;
 153         register int i = 0, cnt = 0;
 154         char ibuf[BUFSIZ];
 155         int tf;
 156
 157         tbuf = bp;
 158         tf = 0;
 159         /*
 160          * TERMCAP can have one of two things in it. It can be the
 161          * name of a file to use instead of /etc/termcap. In this
 162          * case it better start with a "/". Or it can be an entry to
 163          * use so we don't have to read the file. In this case it
 164          * has to already have the newlines crunched out.
 165          */
 166         if (cp && *cp) {
 167                 tf = open(RM = cp, O_RDONLY);
 168         }
 169         if (tf < 0) {
 170                 syslog(LOG_INFO,
 171                        "<%s> open: %s", __FUNCTION__, strerror(errno));
 172                 return (-2);
 173         }
 174         for (;;) {
 175                 cp = bp;
 176                 for (;;) {
 177                         if (i == cnt) {
 178                                 cnt = read(tf, ibuf, BUFSIZ);
 179                                 if (cnt <= 0) {
 180                                         close(tf);
 181                                         return (0);
 182                                 }
 183                                 i = 0;
 184                         }
 185                         c = ibuf[i++];
 186                         if (c == '\n') {
 187                                 if (cp > bp && cp[-1] == '\\') {
 188                                         cp--;
 189                                         continue;
 190                                 }
 191                                 break;
 192                         }
 193                         if (cp >= bp+BUFSIZ) {
 194                                 write(2,"Remcap entry too long\n", 23);
 195                                 break;
 196                         } else
 197                                 *cp++ = c;
 198                 }
 199                 *cp = 0;
 200
 201                 /*
 202                  * The real work for the match.
 203                  */
 204                 if (tnamatch(name)) {
 205                         close(tf);
 206                         return (tnchktc());
 207                 }
 208         }
 209 }
 210
 211 /*
 212  * tnchktc: check the last entry, see if it's tc=xxx. If so,
 213  * recursively find xxx and append that entry (minus the names)
 214  * to take the place of the tc=xxx entry. This allows termcap
 215  * entries to say "like an HP2621 but doesn't turn on the labels".
 216  * Note that this works because of the left to right scan.
 217  */
 218 int
 219 tnchktc()
 220 {
 221         register char *p, *q;
 222         char tcname[16];        /* name of similar terminal */
 223         char tcbuf[BUFSIZ];
 224         char *holdtbuf = tbuf;
 225         int l;
 226
 227         p = tbuf + strlen(tbuf) - 2;    /* before the last colon */
 228         while (*--p != ':')
 229                 if (p<tbuf) {
 230                         write(2, "Bad remcap entry\n", 18);
 231                         return (0);
 232                 }
 233         p++;
 234         /* p now points to beginning of last field */
 235         if (p[0] != 't' || p[1] != 'c')
 236                 return (1);
 237         strlcpy(tcname, p+3, sizeof(tcname));
 238         q = tcname;
 239         while (*q && *q != ':')
 240                 q++;
 241         *q = 0;
 242         if (++hopcount > MAXHOP) {
 243                 write(2, "Infinite tc= loop\n", 18);
 244                 return (0);
 245         }
 246         if (getent(tcbuf, tcname, remotefile) != 1) {
 247                 return (0);
 248         }
 249         for (q = tcbuf; *q++ != ':'; )
 250                 ;
 251         l = p - holdtbuf + strlen(q);
 252
 253         /* check length before copying string below */
 254         if (l > BUFSIZ) {
 255                 write(2, "Remcap entry too long\n", 23);
 256                 q[BUFSIZ - (p-holdtbuf)] = 0;
 257         }
 258         strlcpy(p, q, p-tbuf);
 259         tbuf = holdtbuf;
 260         return (1);
 261 }
 262
 263 /*
 264  * Tnamatch deals with name matching.  The first field of the termcap
 265  * entry is a sequence of names separated by |'s, so we compare
 266  * against each such name.  The normal : terminator after the last
 267  * name (before the first field) stops us.
 268  */
 269 int
 270 tnamatch(np)
 271         char *np;
 272 {
 273         register char *Np, *Bp;
 274
 275         Bp = tbuf;
 276         if (*Bp == '#')
 277                 return (0);
 278         for (;;) {
 279                 for (Np = np; *Np && *Bp == *Np; Bp++, Np++)
 280                         continue;
 281                 if (*Np == 0 && (*Bp == '|' || *Bp == ':' || *Bp == 0))
 282                         return (1);
 283                 while (*Bp && *Bp != ':' && *Bp != '|')
 284                         Bp++;
 285                 if (*Bp == 0 || *Bp == ':')
 286                         return (0);
 287                 Bp++;
 288         }
 289 }
 290
 291 /*
 292  * Skip to the next field.  Notice that this is very dumb, not
 293  * knowing about \: escapes or any such.  If necessary, :'s can be put
 294  * into the termcap file in octal.
 295  */
 296 static char *
 297 tskip(bp)
 298         register char *bp;
 299 {
 300         int dquote;
 301
 302         dquote = 0;
 303         while (*bp) {
 304                 switch (*bp) {
 305                 case ':':
 306                         if (!dquote)
 307                                 goto breakbreak;
 308                         else
 309                                 bp++;
 310                         break;
 311                 case '\\':
 312                         bp++;
 313                         if (isdigit(*bp)) {
 314                                 while (isdigit(*bp++))
 315                                         ;
 316                         } else
 317                                 bp++;
 318                 case '"':
 319                         dquote = (dquote ? 1 : 0);
 320                         bp++;
 321                         break;
 322                 default:
 323                         bp++;
 324                         break;
 325                 }
 326         }
 327 breakbreak:
 328         if (*bp == ':')
 329                 bp++;
 330         return (bp);
 331 }
 332
 333 /*
 334  * Return the (numeric) option id.
 335  * Numeric options look like
 336  *      li#80
 337  * i.e. the option string is separated from the numeric value by
 338  * a # character.  If the option is not found we return -1.
 339  * Note that we handle octal numbers beginning with 0.
 340  */
 341 long long
 342 tgetnum(id)
 343         char *id;
 344 {
 345         register long long i;
 346         register int base;
 347         register char *bp = tbuf;
 348
 349         for (;;) {
 350                 bp = tskip(bp);
 351                 if (*bp == 0)
 352                         return (-1);
 353                 if (strncmp(bp, id, strlen(id)) != 0)
 354                         continue;
 355                 bp += strlen(id);
 356                 if (*bp == '@')
 357                         return (-1);
 358                 if (*bp != '#')
 359                         continue;
 360                 bp++;
 361                 base = 10;
 362                 if (*bp == '0')
 363                         base = 8;
 364                 i = 0;
 365                 while (isdigit(*bp))
 366                         i *= base, i += *bp++ - '0';
 367                 return (i);
 368         }
 369 }
 370
 371 /*
 372  * Handle a flag option.
 373  * Flag options are given "naked", i.e. followed by a : or the end
 374  * of the buffer.  Return 1 if we find the option, or 0 if it is
 375  * not given.
 376  */
 377 int
 378 tgetflag(id)
 379         char *id;
 380 {
 381         register char *bp = tbuf;
 382
 383         for (;;) {
 384                 bp = tskip(bp);
 385                 if (!*bp)
 386                         return (0);
 387                 if (strncmp(bp, id, strlen(id)) == 0) {
 388                         bp += strlen(id);
 389                         if (!*bp || *bp == ':')
 390                                 return (1);
 391                         else if (*bp == '@')
 392                                 return (0);
 393                 }
 394         }
 395 }
 396
 397 /*
 398  * Get a string valued option.
 399  * These are given as
 400  *      cl=^Z
 401  * Much decoding is done on the strings, and the strings are
 402  * placed in area, which is a ref parameter which is updated.
 403  * No checking on area overflow.
 404  */
 405 char *
 406 tgetstr(id, area)
 407         char *id, **area;
 408 {
 409         register char *bp = tbuf;
 410
 411         for (;;) {
 412                 bp = tskip(bp);
 413                 if (!*bp)
 414                         return (0);
 415                 if (strncmp(bp, id, strlen(id)) != 0)
 416                         continue;
 417                 bp += strlen(id);
 418                 if (*bp == '@')
 419                         return (0);
 420                 if (*bp != '=')
 421                         continue;
 422                 bp++;
 423                 return (tdecode(bp, area));
 424         }
 425 }
 426
 427 /*
 428  * Tdecode does the grung work to decode the
 429  * string capability escapes.
 430  */
 431 static char *
 432 tdecode(str, area)
 433         register char *str;
 434         char **area;
 435 {
 436         register char *cp;
 437         register int c;
 438         register char *dp;
 439         int i;
 440         char term;
 441
 442         term = ':';
 443         cp = *area;
 444 again:
 445         if (*str == '"') {
 446                 term = '"';
 447                 str++;
 448         }
 449         while ((c = *str++) && c != term) {
 450                 switch (c) {
 451
 452                 case '^':
 453                         c = *str++ & 037;
 454                         break;
 455
 456                 case '\\':
 457                         dp = "E\033^^\\\\::n\nr\rt\tb\bf\f\"\"";
 458                         c = *str++;
 459 nextc:
 460                         if (*dp++ == c) {
 461                                 c = *dp++;
 462                                 break;
 463                         }
 464                         dp++;
 465                         if (*dp)
 466                                 goto nextc;
 467                         if (isdigit(c)) {
 468                                 c -= '0', i = 2;
 469                                 do
 470                                         c <<= 3, c |= *str++ - '0';
 471                                 while (--i && isdigit(*str));
 472                         }
 473                         break;
 474                 }
 475                 *cp++ = c;
 476         }
 477         if (c == term && term != ':') {
 478                 term = ':';
 479                 goto again;
 480         }
 481         *cp++ = 0;
 482         str = *area;
 483         *area = cp;
 484         return (str);
 485 }