rtadvd.tproj/advcap.c

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