1 /* $NetBSD: advcap.c,v 1.17 2017/11/06 15:15:04 christos Exp $ */ 2 /* $KAME: advcap.c,v 1.11 2003/05/19 09:46:50 keiichi Exp $ */ 3 4 /* 5 * Copyright (c) 1983 The Regents of the University of California. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 /* 34 * remcap - routines for dealing with the remote host data base 35 * 36 * derived from termcap 37 */ 38 #include <sys/types.h> 39 #include <sys/uio.h> 40 #include <unistd.h> 41 #include <fcntl.h> 42 #include <ctype.h> 43 #include <stdlib.h> 44 #include <stdio.h> 45 #include <syslog.h> 46 #include <errno.h> 47 #include <string.h> 48 #include "pathnames.h" 49 #include "prog_ops.h" 50 51 #include "logit.h" 52 53 #ifndef __UNCONST 54 #define __UNCONST(a) ((void *)(unsigned long)(const void *)(a)) 55 #endif 56 57 #ifndef BUFSIZ 58 #define BUFSIZ 1024 59 #endif 60 #define MAXHOP 32 /* max number of tc= indirections */ 61 62 #define tgetent agetent 63 #define tnchktc anchktc 64 #define tnamatch anamatch 65 #define tgetnum agetnum 66 #define tgetflag agetflag 67 #define tgetstr agetstr 68 69 #if 0 70 #define V_TERMCAP "REMOTE" 71 #define V_TERM "HOST" 72 #endif 73 74 char *RM; 75 76 /* 77 * termcap - routines for dealing with the terminal capability data base 78 * 79 * BUG: Should use a "last" pointer in tbuf, so that searching 80 * for capabilities alphabetically would not be a n**2/2 81 * process when large numbers of capabilities are given. 82 * Note: If we add a last pointer now we will screw up the 83 * tc capability. We really should compile termcap. 84 * 85 * Essentially all the work here is scanning and decoding escapes 86 * in string capabilities. We don't use stdio because the editor 87 * doesn't, and because living w/o it is not hard. 88 */ 89 90 static char *tbuf; 91 static int hopcount; /* detect infinite loops in termcap, init 0 */ 92 93 static char *remotefile; 94 95 extern char *conffile; 96 97 int tgetent(char *, char *); 98 int getent(char *, char *, char *); 99 int tnchktc(void); 100 int tnamatch(char *); 101 static char *tskip(char *); 102 int64_t tgetnum(char *); 103 int tgetflag(char *); 104 char *tgetstr(char *, char **); 105 static char *tdecode(char *, char **); 106 107 /* 108 * Get an entry for terminal name in buffer bp, 109 * from the termcap file. Parse is very rudimentary; 110 * we just notice escaped newlines. 111 */ 112 int 113 tgetent(char *bp, char *name) 114 { 115 char *cp; 116 117 remotefile = cp = conffile ? conffile : __UNCONST(_PATH_RTADVDCONF); 118 return (getent(bp, name, cp)); 119 } 120 121 int 122 getent(char *bp, char *name, char *cp) 123 { 124 int c; 125 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 logit(LOG_INFO, "<%s> open: %m", __func__); 143 return (-2); 144 } 145 for (;;) { 146 cp = bp; 147 for (;;) { 148 if (i == cnt) { 149 cnt = read(tf, ibuf, BUFSIZ); 150 if (cnt <= 0) { 151 close(tf); 152 return (0); 153 } 154 i = 0; 155 } 156 c = ibuf[i++]; 157 if (c == '\n') { 158 if (cp > bp && cp[-1] == '\\') { 159 cp--; 160 continue; 161 } 162 break; 163 } 164 if (cp >= bp + BUFSIZ) { 165 prog_write(2,"Remcap entry too long\n", 23); 166 break; 167 } else 168 *cp++ = c; 169 } 170 *cp = 0; 171 172 /* 173 * The real work for the match. 174 */ 175 if (tnamatch(name)) { 176 close(tf); 177 return (tnchktc()); 178 } 179 } 180 } 181 182 /* 183 * tnchktc: check the last entry, see if it's tc=xxx. If so, 184 * recursively find xxx and append that entry (minus the names) 185 * to take the place of the tc=xxx entry. This allows termcap 186 * entries to say "like an HP2621 but doesn't turn on the labels". 187 * Note that this works because of the left to right scan. 188 */ 189 int 190 tnchktc(void) 191 { 192 char *p, *q; 193 char tcname[16]; /* name of similar terminal */ 194 char tcbuf[BUFSIZ]; 195 char *holdtbuf = tbuf; 196 int l; 197 198 p = tbuf + strlen(tbuf) - 2; /* before the last colon */ 199 while (*--p != ':') 200 if (p < tbuf) { 201 prog_write(2, "Bad remcap entry\n", 18); 202 return (0); 203 } 204 p++; 205 /* p now points to beginning of last field */ 206 if (p[0] != 't' || p[1] != 'c') 207 return (1); 208 strlcpy(tcname, p + 3, sizeof tcname); 209 q = tcname; 210 while (*q && *q != ':') 211 q++; 212 *q = 0; 213 if (++hopcount > MAXHOP) { 214 prog_write(2, "Infinite tc= loop\n", 18); 215 return (0); 216 } 217 if (getent(tcbuf, tcname, remotefile) != 1) { 218 return (0); 219 } 220 for (q = tcbuf; *q++ != ':'; ) 221 ; 222 l = p - holdtbuf + strlen(q); 223 if (l > BUFSIZ) { 224 prog_write(2, "Remcap entry too long\n", 23); 225 q[BUFSIZ - (p-holdtbuf)] = 0; 226 } 227 strcpy(p, q); 228 tbuf = holdtbuf; 229 return (1); 230 } 231 232 /* 233 * Tnamatch deals with name matching. The first field of the termcap 234 * entry is a sequence of names separated by |'s, so we compare 235 * against each such name. The normal : terminator after the last 236 * name (before the first field) stops us. 237 */ 238 int 239 tnamatch(char *np) 240 { 241 char *Np, *Bp; 242 243 Bp = tbuf; 244 if (*Bp == '#') 245 return (0); 246 for (;;) { 247 for (Np = np; *Np && *Bp == *Np; Bp++, Np++) 248 continue; 249 if (*Np == 0 && (*Bp == '|' || *Bp == ':' || *Bp == 0)) 250 return (1); 251 while (*Bp && *Bp != ':' && *Bp != '|') 252 Bp++; 253 if (*Bp == 0 || *Bp == ':') 254 return (0); 255 Bp++; 256 } 257 } 258 259 /* 260 * Skip to the next field. Notice that this is very dumb, not 261 * knowing about \: escapes or any such. If necessary, :'s can be put 262 * into the termcap file in octal. 263 */ 264 static char * 265 tskip(char *bp) 266 { 267 int dquote; 268 269 dquote = 0; 270 while (*bp) { 271 switch (*bp) { 272 case ':': 273 if (!dquote) 274 goto breakbreak; 275 else 276 bp++; 277 break; 278 case '\\': 279 bp++; 280 if (isdigit((unsigned char)*bp)) { 281 while (isdigit((unsigned char)*bp++)) 282 ; 283 } else 284 bp++; 285 case '"': 286 dquote = (dquote ? 0 : 1); 287 bp++; 288 break; 289 default: 290 bp++; 291 break; 292 } 293 } 294 breakbreak: 295 if (*bp == ':') 296 bp++; 297 return (bp); 298 } 299 300 /* 301 * Return the (numeric) option id. 302 * Numeric options look like 303 * li#80 304 * i.e. the option string is separated from the numeric value by 305 * a # character. If the option is not found we return -1. 306 * Note that we handle octal numbers beginning with 0. 307 */ 308 int64_t 309 tgetnum(char *id) 310 { 311 int64_t i; 312 int base; 313 char *bp = tbuf; 314 315 for (;;) { 316 bp = tskip(bp); 317 if (*bp == 0) 318 return (-1); 319 if (strncmp(bp, id, strlen(id)) != 0) 320 continue; 321 bp += strlen(id); 322 if (*bp == '@') 323 return (-1); 324 if (*bp != '#') 325 continue; 326 bp++; 327 base = 10; 328 if (*bp == '0') 329 base = 8; 330 i = 0; 331 while (isdigit((unsigned char)*bp)) 332 i *= base, i += *bp++ - '0'; 333 return (i); 334 } 335 } 336 337 /* 338 * Handle a flag option. 339 * Flag options are given "naked", i.e. followed by a : or the end 340 * of the buffer. Return 1 if we find the option, or 0 if it is 341 * not given. 342 */ 343 int 344 tgetflag(char *id) 345 { 346 char *bp = tbuf; 347 348 for (;;) { 349 bp = tskip(bp); 350 if (!*bp) 351 return (0); 352 if (strncmp(bp, id, strlen(id)) == 0) { 353 bp += strlen(id); 354 if (!*bp || *bp == ':') 355 return (1); 356 else if (*bp == '@') 357 return (0); 358 } 359 } 360 } 361 362 /* 363 * Get a string valued option. 364 * These are given as 365 * cl=^Z 366 * Much decoding is done on the strings, and the strings are 367 * placed in area, which is a ref parameter which is updated. 368 * No checking on area overflow. 369 */ 370 char * 371 tgetstr(char *id, char **area) 372 { 373 char *bp = tbuf; 374 375 for (;;) { 376 bp = tskip(bp); 377 if (!*bp) 378 return (0); 379 if (strncmp(bp, id, strlen(id)) != 0) 380 continue; 381 bp += strlen(id); 382 if (*bp == '@') 383 return (0); 384 if (*bp != '=') 385 continue; 386 bp++; 387 return (tdecode(bp, area)); 388 } 389 } 390 391 /* 392 * Tdecode does the grung work to decode the 393 * string capability escapes. 394 */ 395 static char * 396 tdecode(char *str, char **area) 397 { 398 char *cp; 399 int c; 400 const char *dps = "E\033^^\\\\::n\nr\rt\tb\bf\f\"\"", *dp; 401 int i; 402 char term; 403 404 term = ':'; 405 cp = *area; 406 again: 407 if (*str == '"') { 408 term = '"'; 409 str++; 410 } 411 while ((c = *str++) && c != term) { 412 switch (c) { 413 414 case '^': 415 c = *str++ & 037; 416 break; 417 418 case '\\': 419 dp = dps; 420 c = *str++; 421 nextc: 422 if (*dp++ == c) { 423 c = *dp++; 424 break; 425 } 426 dp++; 427 if (*dp) 428 goto nextc; 429 if (isdigit((unsigned char)c)) { 430 c -= '0', i = 2; 431 do 432 c <<= 3, c |= *str++ - '0'; 433 while (--i && isdigit((unsigned char)*str)); 434 } 435 break; 436 } 437 *cp++ = c; 438 } 439 if (c == term && term != ':') { 440 term = ':'; 441 goto again; 442 } 443 *cp++ = 0; 444 str = *area; 445 *area = cp; 446 return (str); 447 } 448