network_cmds/rtadvd.tproj/advcap.c

   1 /*
   2  * Copyright (c) 2009-2011 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 1.11 2003/05/19 09:46:50 keiichi 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
  64 /*
  65  * remcap - routines for dealing with the remote host data base
  66  *
  67  * derived from termcap
  68  */
  69 #include <sys/types.h>
  70 #include <sys/uio.h>
  71 #include <unistd.h>
  72 #include <fcntl.h>
  73 #include <ctype.h>
  74 #include <stdlib.h>
  75 #include <stdio.h>
  76 #include <errno.h>
  77 #include <string.h>
  78 #include "pathnames.h"
  79 #include "rtadvd_logging.h"
  80
  81 #ifndef BUFSIZ
  82 #define BUFSIZ          1024
  83 #endif
  84 #define MAXHOP          32              /* max number of tc= indirections */
  85
  86 #define tgetent         agetent
  87 #define tnchktc         anchktc
  88 #define tnamatch        anamatch
  89 #define tgetnum         agetnum
  90 #define tgetflag        agetflag
  91 #define tgetstr         agetstr
  92
  93 #if 0
  94 #define V_TERMCAP       "REMOTE"
  95 #define V_TERM          "HOST"
  96 #endif
  97
  98 char    *RM;
  99
 100 /*
 101  * termcap - routines for dealing with the terminal capability data base
 102  *
 103  * BUG:         Should use a "last" pointer in tbuf, so that searching
 104  *              for capabilities alphabetically would not be a n**2/2
 105  *              process when large numbers of capabilities are given.
 106  * Note:        If we add a last pointer now we will screw up the
 107  *              tc capability. We really should compile termcap.
 108  *
 109  * Essentially all the work here is scanning and decoding escapes
 110  * in string capabilities.  We don't use stdio because the editor
 111  * doesn't, and because living w/o it is not hard.
 112  */
 113
 114 static  char *tbuf;
 115 static  int hopcount;   /* detect infinite loops in termcap, init 0 */
 116
 117 static  char *remotefile;
 118
 119 extern char *conffile;
 120
 121 int tgetent(char *, char *);
 122 int getent(char *, char *, char *);
 123 int tnchktc(void);
 124 int tnamatch(char *);
 125 static char *tskip(char *);
 126 int64_t tgetnum(char *);
 127 int tgetflag(char *);
 128 char *tgetstr(char *, char **);
 129 static char *tdecode(char *, char **);
 130
 131 /*
 132  * Get an entry for terminal name in buffer bp,
 133  * from the termcap file.  Parse is very rudimentary;
 134  * we just notice escaped newlines.
 135  */
 136 int
 137 tgetent(bp, name)
 138         char *bp, *name;
 139 {
 140         char *cp;
 141
 142         remotefile = cp = conffile ? conffile : _PATH_RTADVDCONF;
 143         return (getent(bp, name, cp));
 144 }
 145
 146 int
 147 getent(bp, name, cp)
 148         char *bp, *name, *cp;
 149 {
 150         int c;
 151         int i = 0, cnt = 0;
 152         char ibuf[BUFSIZ];
 153         int tf;
 154
 155         tbuf = bp;
 156         tf = 0;
 157         /*
 158          * TERMCAP can have one of two things in it. It can be the
 159          * name of a file to use instead of /etc/termcap. In this
 160          * case it better start with a "/". Or it can be an entry to
 161          * use so we don't have to read the file. In this case it
 162          * has to already have the newlines crunched out.
 163          */
 164         if (cp && *cp) {
 165                 tf = open(RM = cp, O_RDONLY);
 166         }
 167         if (tf < 0) {
 168                 infolog("<%s> open: %s", __func__, strerror(errno));
 169                 return (-2);
 170         }
 171         for (;;) {
 172                 cp = bp;
 173                 for (;;) {
 174                         if (i == cnt) {
 175                                 cnt = read(tf, ibuf, BUFSIZ);
 176                                 if (cnt <= 0) {
 177                                         close(tf);
 178                                         return (0);
 179                                 }
 180                                 i = 0;
 181                         }
 182                         c = ibuf[i++];
 183                         if (c == '\n') {
 184                                 if (cp > bp && cp[-1] == '\\') {
 185                                         cp--;
 186                                         continue;
 187                                 }
 188                                 break;
 189                         }
 190                         if (cp >= bp + BUFSIZ - 1) {
 191                                 write(STDERR_FILENO, "Remcap entry too long\n",
 192                                       22);
 193                                 break;
 194                         } else
 195                                 *cp++ = c;
 196                 }
 197                 *cp = 0;
 198
 199                 /*
 200                  * The real work for the match.
 201                  */
 202                 if (tnamatch(name)) {
 203                         close(tf);
 204                         return (tnchktc());
 205                 }
 206         }
 207 }
 208
 209 /*
 210  * tnchktc: check the last entry, see if it's tc=xxx. If so,
 211  * recursively find xxx and append that entry (minus the names)
 212  * to take the place of the tc=xxx entry. This allows termcap
 213  * entries to say "like an HP2621 but doesn't turn on the labels".
 214  * Note that this works because of the left to right scan.
 215  */
 216 int
 217 tnchktc()
 218 {
 219         char *p, *q;
 220         char tcname[16];        /* name of similar terminal */
 221         char tcbuf[BUFSIZ];
 222         char *holdtbuf = tbuf;
 223         int l;
 224
 225         p = tbuf + strlen(tbuf) - 2;    /* before the last colon */
 226         while (*--p != ':')
 227                 if (p < tbuf) {
 228                         write(STDERR_FILENO, "Bad remcap entry\n", 18);
 229                         return (0);
 230                 }
 231         p++;
 232         /* p now points to beginning of last field */
 233         if (p[0] != 't' || p[1] != 'c')
 234                 return (1);
 235         strlcpy(tcname, p + 3, sizeof tcname);
 236         q = tcname;
 237         while (*q && *q != ':')
 238                 q++;
 239         *q = 0;
 240         if (++hopcount > MAXHOP) {
 241                 write(STDERR_FILENO, "Infinite tc= loop\n", 18);
 242                 return (0);
 243         }
 244         if (getent(tcbuf, tcname, remotefile) != 1) {
 245                 return (0);
 246         }
 247         for (q = tcbuf; *q++ != ':'; )
 248                 ;
 249         l = p - holdtbuf + strlen(q);
 250
 251         /* check length before copying string below */
 252         if (l > BUFSIZ) {
 253                 write(STDERR_FILENO, "Remcap entry too long\n", 23);
 254                 q[BUFSIZ - (p-holdtbuf)] = 0;
 255         }
 256         strlcpy(p, q, p-tbuf);
 257         tbuf = holdtbuf;
 258         return (1);
 259 }
 260
 261 /*
 262  * Tnamatch deals with name matching.  The first field of the termcap
 263  * entry is a sequence of names separated by |'s, so we compare
 264  * against each such name.  The normal : terminator after the last
 265  * name (before the first field) stops us.
 266  */
 267 int
 268 tnamatch(np)
 269         char *np;
 270 {
 271         char *Np, *Bp;
 272
 273         Bp = tbuf;
 274         if (*Bp == '#')
 275                 return (0);
 276         for (;;) {
 277                 for (Np = np; *Np && *Bp == *Np; Bp++, Np++)
 278                         continue;
 279                 if (*Np == 0 && (*Bp == '|' || *Bp == ':' || *Bp == 0))
 280                         return (1);
 281                 while (*Bp && *Bp != ':' && *Bp != '|')
 282                         Bp++;
 283                 if (*Bp == 0 || *Bp == ':')
 284                         return (0);
 285                 Bp++;
 286         }
 287 }
 288
 289 /*
 290  * Skip to the next field.  Notice that this is very dumb, not
 291  * knowing about \: escapes or any such.  If necessary, :'s can be put
 292  * into the termcap file in octal.
 293  */
 294 static char *
 295 tskip(bp)
 296         char *bp;
 297 {
 298         int dquote;
 299
 300         dquote = 0;
 301         while (*bp) {
 302                 switch (*bp) {
 303                 case ':':
 304                         if (!dquote)
 305                                 goto breakbreak;
 306                         else
 307                                 bp++;
 308                         break;
 309                 case '\\':
 310                         bp++;
 311                         if (isdigit(*bp)) {
 312                                 while (isdigit(*bp++))
 313                                         ;
 314                         } else
 315                                 bp++;
 316                 case '"':
 317                         dquote = (dquote ? 1 : 0);
 318                         bp++;
 319                         break;
 320                 default:
 321                         bp++;
 322                         break;
 323                 }
 324         }
 325 breakbreak:
 326         if (*bp == ':')
 327                 bp++;
 328         return (bp);
 329 }
 330
 331 /*
 332  * Return the (numeric) option id.
 333  * Numeric options look like
 334  *      li#80
 335  * i.e. the option string is separated from the numeric value by
 336  * a # character.  If the option is not found we return -1.
 337  * Note that we handle octal numbers beginning with 0.
 338  */
 339 int64_t
 340 tgetnum(id)
 341         char *id;
 342 {
 343         int64_t i;
 344         int base;
 345         char *bp = tbuf;
 346
 347         for (;;) {
 348                 bp = tskip(bp);
 349                 if (*bp == 0)
 350                         return (-1);
 351                 if (strncmp(bp, id, strlen(id)) != 0)
 352                         continue;
 353                 bp += strlen(id);
 354                 if (*bp == '@')
 355                         return (-1);
 356                 if (*bp != '#')
 357                         continue;
 358                 bp++;
 359                 base = 10;
 360                 if (*bp == '0')
 361                         base = 8;
 362                 i = 0;
 363                 while (isdigit(*bp))
 364                         i *= base, i += *bp++ - '0';
 365                 return (i);
 366         }
 367 }
 368
 369 /*
 370  * Handle a flag option.
 371  * Flag options are given "naked", i.e. followed by a : or the end
 372  * of the buffer.  Return 1 if we find the option, or 0 if it is
 373  * not given.
 374  */
 375 int
 376 tgetflag(id)
 377         char *id;
 378 {
 379         char *bp = tbuf;
 380
 381         for (;;) {
 382                 bp = tskip(bp);
 383                 if (!*bp)
 384                         return (0);
 385                 if (strncmp(bp, id, strlen(id)) == 0) {
 386                         bp += strlen(id);
 387                         if (!*bp || *bp == ':')
 388                                 return (1);
 389                         else if (*bp == '@')
 390                                 return (0);
 391                 }
 392         }
 393 }
 394
 395 /*
 396  * Get a string valued option.
 397  * These are given as
 398  *      cl=^Z
 399  * Much decoding is done on the strings, and the strings are
 400  * placed in area, which is a ref parameter which is updated.
 401  * No checking on area overflow.
 402  */
 403 char *
 404 tgetstr(id, area)
 405         char *id, **area;
 406 {
 407         char *bp = tbuf;
 408
 409         for (;;) {
 410                 bp = tskip(bp);
 411                 if (!*bp)
 412                         return (0);
 413                 if (strncmp(bp, id, strlen(id)) != 0)
 414                         continue;
 415                 bp += strlen(id);
 416                 if (*bp == '@')
 417                         return (0);
 418                 if (*bp != '=')
 419                         continue;
 420                 bp++;
 421                 return (tdecode(bp, area));
 422         }
 423 }
 424
 425 /*
 426  * Tdecode does the grung work to decode the
 427  * string capability escapes.
 428  */
 429 static char *
 430 tdecode(str, area)
 431         char *str;
 432         char **area;
 433 {
 434         char *cp;
 435         int c;
 436         char *dp;
 437         int i;
 438         char term;
 439
 440         term = ':';
 441         cp = *area;
 442 again:
 443         if (*str == '"') {
 444                 term = '"';
 445                 str++;
 446         }
 447         while ((c = *str++) && c != term) {
 448                 switch (c) {
 449
 450                 case '^':
 451                         c = *str++ & 037;
 452                         break;
 453
 454                 case '\\':
 455                         dp = "E\033^^\\\\::n\nr\rt\tb\bf\f\"\"";
 456                         c = *str++;
 457 nextc:
 458                         if (*dp++ == c) {
 459                                 c = *dp++;
 460                                 break;
 461                         }
 462                         dp++;
 463                         if (*dp)
 464                                 goto nextc;
 465                         if (isdigit(c)) {
 466                                 c -= '0', i = 2;
 467                                 do
 468                                         c <<= 3, c |= *str++ - '0';
 469                                 while (--i && isdigit(*str));
 470                         }
 471                         break;
 472                 }
 473                 *cp++ = c;
 474         }
 475         if (c == term && term != ':') {
 476                 term = ':';
 477                 goto again;
 478         }
 479         *cp++ = 0;
 480         str = *area;
 481         *area = cp;
 482         return (str);
 483 }