| 1 | /* |
| 2 | * setup.c |
| 3 | * - configuration file parsing |
| 4 | * - management of global state |
| 5 | */ |
| 6 | /* |
| 7 | * This file is part of adns, which is Copyright (C) 1997, 1998 Ian Jackson |
| 8 | * |
| 9 | * This program is free software; you can redistribute it and/or modify |
| 10 | * it under the terms of the GNU General Public License as published by |
| 11 | * the Free Software Foundation; either version 2, or (at your option) |
| 12 | * any later version. |
| 13 | * |
| 14 | * This program is distributed in the hope that it will be useful, |
| 15 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 16 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 17 | * GNU General Public License for more details. |
| 18 | * |
| 19 | * You should have received a copy of the GNU General Public License |
| 20 | * along with this program; if not, write to the Free Software Foundation, |
| 21 | * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
| 22 | */ |
| 23 | |
| 24 | #include <stdlib.h> |
| 25 | #include <errno.h> |
| 26 | #include <string.h> |
| 27 | #include <unistd.h> |
| 28 | #include <fcntl.h> |
| 29 | |
| 30 | #include <netdb.h> |
| 31 | #include <arpa/inet.h> |
| 32 | |
| 33 | #include "internal.h" |
| 34 | |
| 35 | static void readconfig(adns_state ads, const char *filename); |
| 36 | |
| 37 | static void addserver(adns_state ads, struct in_addr addr) { |
| 38 | int i; |
| 39 | struct server *ss; |
| 40 | |
| 41 | for (i=0; i<ads->nservers; i++) { |
| 42 | if (ads->servers[i].addr.s_addr == addr.s_addr) { |
| 43 | adns__debug(ads,-1,0,"duplicate nameserver %s ignored",inet_ntoa(addr)); |
| 44 | return; |
| 45 | } |
| 46 | } |
| 47 | |
| 48 | if (ads->nservers>=MAXSERVERS) { |
| 49 | adns__diag(ads,-1,0,"too many nameservers, ignoring %s",inet_ntoa(addr)); |
| 50 | return; |
| 51 | } |
| 52 | |
| 53 | ss= ads->servers+ads->nservers; |
| 54 | ss->addr= addr; |
| 55 | ads->nservers++; |
| 56 | } |
| 57 | |
| 58 | static void saveerr(adns_state ads, int en) { |
| 59 | if (!ads->configerrno) ads->configerrno= en; |
| 60 | } |
| 61 | |
| 62 | static void configparseerr(adns_state ads, const char *fn, int lno, |
| 63 | const char *fmt, ...) { |
| 64 | va_list al; |
| 65 | |
| 66 | saveerr(ads,EINVAL); |
| 67 | if (!ads->diagfile || (ads->iflags & adns_if_noerrprint)) return; |
| 68 | |
| 69 | if (lno==-1) fprintf(ads->diagfile,"adns: %s: ",fn); |
| 70 | else fprintf(ads->diagfile,"adns: %s:%d: ",fn,lno); |
| 71 | va_start(al,fmt); |
| 72 | vfprintf(ads->diagfile,fmt,al); |
| 73 | va_end(al); |
| 74 | fputc('\n',ads->diagfile); |
| 75 | } |
| 76 | |
| 77 | static void ccf_nameserver(adns_state ads, const char *fn, int lno, const char *buf) { |
| 78 | struct in_addr ia; |
| 79 | |
| 80 | if (!inet_aton(buf,&ia)) { |
| 81 | configparseerr(ads,fn,lno,"invalid nameserver address `%s'",buf); |
| 82 | return; |
| 83 | } |
| 84 | adns__debug(ads,-1,0,"using nameserver %s",inet_ntoa(ia)); |
| 85 | addserver(ads,ia); |
| 86 | } |
| 87 | |
| 88 | static void ccf_search(adns_state ads, const char *fn, int lno, const char *buf) { |
| 89 | if (!buf) return; |
| 90 | adns__diag(ads,-1,0,"warning - `search' ignored fixme"); |
| 91 | } |
| 92 | |
| 93 | static void ccf_sortlist(adns_state ads, const char *fn, int lno, const char *bufp) { |
| 94 | const char *p, *q; |
| 95 | char tbuf[200], *slash, *ep; |
| 96 | struct in_addr base, mask; |
| 97 | int l; |
| 98 | unsigned long initial, baselocal; |
| 99 | |
| 100 | ads->nsortlist= 0; |
| 101 | if (!bufp) return; |
| 102 | |
| 103 | for (;;) { |
| 104 | while (ctype_whitespace(*bufp)) bufp++; |
| 105 | if (!*bufp) return; |
| 106 | |
| 107 | q= bufp; |
| 108 | while (*q && !ctype_whitespace(*q)) q++; |
| 109 | |
| 110 | p= bufp; |
| 111 | l= q-p; |
| 112 | bufp= q; |
| 113 | |
| 114 | if (ads->nsortlist >= MAXSORTLIST) { |
| 115 | adns__diag(ads,-1,0,"too many sortlist entries, ignoring %.*s onwards",l,p); |
| 116 | return; |
| 117 | } |
| 118 | |
| 119 | if (l >= sizeof(tbuf)) { |
| 120 | configparseerr(ads,fn,lno,"sortlist entry `%.*s' too long",l,p); |
| 121 | continue; |
| 122 | } |
| 123 | |
| 124 | memcpy(tbuf,p,l); |
| 125 | slash= strchr(tbuf,'/'); |
| 126 | if (slash) *slash++= 0; |
| 127 | |
| 128 | if (!inet_aton(tbuf,&base)) { |
| 129 | configparseerr(ads,fn,lno,"invalid address `%s' in sortlist",tbuf); |
| 130 | continue; |
| 131 | } |
| 132 | |
| 133 | if (slash) { |
| 134 | if (strchr(slash,'.')) { |
| 135 | if (!inet_aton(slash,&mask)) { |
| 136 | configparseerr(ads,fn,lno,"invalid mask `%s' in sortlist",slash); |
| 137 | continue; |
| 138 | } |
| 139 | if (base.s_addr & ~mask.s_addr) { |
| 140 | configparseerr(ads,fn,lno, |
| 141 | "mask `%s' in sortlist overlaps address `%s'",slash,tbuf); |
| 142 | continue; |
| 143 | } |
| 144 | } else { |
| 145 | initial= strtoul(slash,&ep,10); |
| 146 | if (*ep || initial>32) { |
| 147 | configparseerr(ads,fn,lno,"mask length `%s' invalid",slash); |
| 148 | continue; |
| 149 | } |
| 150 | mask.s_addr= htonl((0x0ffffffffUL) << (32-initial)); |
| 151 | } |
| 152 | } else { |
| 153 | baselocal= ntohl(base.s_addr); |
| 154 | if (!baselocal & 0x080000000UL) /* class A */ |
| 155 | mask.s_addr= htonl(0x0ff000000UL); |
| 156 | else if ((baselocal & 0x0c0000000UL) == 0x080000000UL) |
| 157 | mask.s_addr= htonl(0x0ffff0000UL); /* class B */ |
| 158 | else if ((baselocal & 0x0f0000000UL) == 0x0e0000000UL) |
| 159 | mask.s_addr= htonl(0x0ff000000UL); /* class C */ |
| 160 | else { |
| 161 | configparseerr(ads,fn,lno, |
| 162 | "network address `%s' in sortlist is not in classed ranges," |
| 163 | " must specify mask explicitly", tbuf); |
| 164 | continue; |
| 165 | } |
| 166 | } |
| 167 | |
| 168 | ads->sortlist[ads->nsortlist].base= base; |
| 169 | ads->sortlist[ads->nsortlist].mask= mask; |
| 170 | ads->nsortlist++; |
| 171 | } |
| 172 | } |
| 173 | |
| 174 | static void ccf_options(adns_state ads, const char *fn, int lno, const char *buf) { |
| 175 | if (!buf) return; |
| 176 | adns__diag(ads,-1,0,"warning - `options' ignored fixme"); |
| 177 | } |
| 178 | |
| 179 | static void ccf_clearnss(adns_state ads, const char *fn, int lno, const char *buf) { |
| 180 | ads->nservers= 0; |
| 181 | } |
| 182 | |
| 183 | static void ccf_include(adns_state ads, const char *fn, int lno, const char *buf) { |
| 184 | if (!*buf) { |
| 185 | configparseerr(ads,fn,lno,"`include' directive with no filename"); |
| 186 | return; |
| 187 | } |
| 188 | readconfig(ads,buf); |
| 189 | } |
| 190 | |
| 191 | static const struct configcommandinfo { |
| 192 | const char *name; |
| 193 | void (*fn)(adns_state ads, const char *fn, int lno, const char *buf); |
| 194 | } configcommandinfos[]= { |
| 195 | { "nameserver", ccf_nameserver }, |
| 196 | { "domain", ccf_search }, |
| 197 | { "search", ccf_search }, |
| 198 | { "sortlist", ccf_sortlist }, |
| 199 | { "options", ccf_options }, |
| 200 | { "clearnameservers", ccf_clearnss }, |
| 201 | { "include", ccf_include }, |
| 202 | { 0 } |
| 203 | }; |
| 204 | |
| 205 | typedef union { |
| 206 | FILE *file; |
| 207 | const char *text; |
| 208 | } getline_ctx; |
| 209 | |
| 210 | static int gl_file(adns_state ads, getline_ctx *src_io, const char *filename, |
| 211 | int lno, char *buf, int buflen) { |
| 212 | FILE *file= src_io->file; |
| 213 | int c, i; |
| 214 | char *p; |
| 215 | |
| 216 | p= buf; |
| 217 | buflen--; |
| 218 | i= 0; |
| 219 | |
| 220 | for (;;) { /* loop over chars */ |
| 221 | if (i == buflen) { |
| 222 | adns__diag(ads,-1,0,"%s:%d: line too long, ignored",filename,lno); |
| 223 | goto x_badline; |
| 224 | } |
| 225 | c= getc(file); |
| 226 | if (!c) { |
| 227 | adns__diag(ads,-1,0,"%s:%d: line contains nul, ignored",filename,lno); |
| 228 | goto x_badline; |
| 229 | } else if (c == '\n') { |
| 230 | break; |
| 231 | } else if (c == EOF) { |
| 232 | if (ferror(file)) { |
| 233 | saveerr(ads,errno); |
| 234 | adns__diag(ads,-1,0,"%s:%d: read error: %s",filename,lno,strerror(errno)); |
| 235 | return -1; |
| 236 | } |
| 237 | if (!i) return -1; |
| 238 | break; |
| 239 | } else { |
| 240 | *p++= c; |
| 241 | i++; |
| 242 | } |
| 243 | } |
| 244 | |
| 245 | *p++= 0; |
| 246 | return i; |
| 247 | |
| 248 | x_badline: |
| 249 | saveerr(ads,EINVAL); |
| 250 | while ((c= getc(file)) != EOF && c != '\n'); |
| 251 | return -2; |
| 252 | } |
| 253 | |
| 254 | static int gl_text(adns_state ads, getline_ctx *src_io, const char *filename, |
| 255 | int lno, char *buf, int buflen) { |
| 256 | const char *cp= src_io->text; |
| 257 | int l; |
| 258 | |
| 259 | if (!cp || !*cp) return -1; |
| 260 | |
| 261 | if (*cp == ';' || *cp == '\n') cp++; |
| 262 | l= strcspn(cp,";\n"); |
| 263 | src_io->text = cp+l; |
| 264 | |
| 265 | if (l >= buflen) { |
| 266 | adns__diag(ads,-1,0,"%s:%d: line too long, ignored",filename,lno); |
| 267 | saveerr(ads,EINVAL); |
| 268 | return -2; |
| 269 | } |
| 270 | |
| 271 | memcpy(buf,cp,l); |
| 272 | buf[l]= 0; |
| 273 | return l; |
| 274 | } |
| 275 | |
| 276 | static void readconfiggeneric(adns_state ads, const char *filename, |
| 277 | int (*getline)(adns_state ads, getline_ctx*, |
| 278 | const char *filename, int lno, |
| 279 | char *buf, int buflen), |
| 280 | /* Returns >=0 for success, -1 for EOF or error |
| 281 | * (error will have been reported), or -2 for |
| 282 | * bad line was encountered, try again. |
| 283 | */ |
| 284 | getline_ctx gl_ctx) { |
| 285 | char linebuf[2000], *p, *q; |
| 286 | int lno, l, dirl; |
| 287 | const struct configcommandinfo *ccip; |
| 288 | |
| 289 | for (lno=1; |
| 290 | (l= getline(ads,&gl_ctx, filename,lno, linebuf,sizeof(linebuf))) != -1; |
| 291 | lno++) { |
| 292 | if (l == -2) continue; |
| 293 | while (l>0 && ctype_whitespace(linebuf[l-1])) l--; |
| 294 | linebuf[l]= 0; |
| 295 | p= linebuf; |
| 296 | while (ctype_whitespace(*p)) p++; |
| 297 | if (*p == '#' || !*p) continue; |
| 298 | q= p; |
| 299 | while (*q && !ctype_whitespace(*q)) q++; |
| 300 | dirl= q-p; |
| 301 | for (ccip=configcommandinfos; |
| 302 | ccip->name && !(strlen(ccip->name)==dirl && !memcmp(ccip->name,p,q-p)); |
| 303 | ccip++); |
| 304 | if (!ccip->name) { |
| 305 | adns__diag(ads,-1,0,"%s:%d: unknown configuration directive `%.*s'", |
| 306 | filename,lno,q-p,p); |
| 307 | continue; |
| 308 | } |
| 309 | while (ctype_whitespace(*q)) q++; |
| 310 | ccip->fn(ads,filename,lno,q); |
| 311 | } |
| 312 | } |
| 313 | |
| 314 | static const char *instrum_getenv(adns_state ads, const char *envvar) { |
| 315 | const char *value; |
| 316 | |
| 317 | value= getenv(envvar); |
| 318 | if (!value) adns__debug(ads,-1,0,"environment variable %s not set",envvar); |
| 319 | else adns__debug(ads,-1,0,"environment variable %s set to `%s'",envvar,value); |
| 320 | return value; |
| 321 | } |
| 322 | |
| 323 | static void readconfig(adns_state ads, const char *filename) { |
| 324 | getline_ctx gl_ctx; |
| 325 | |
| 326 | gl_ctx.file= fopen(filename,"r"); |
| 327 | if (!gl_ctx.file) { |
| 328 | if (errno == ENOENT) { |
| 329 | adns__debug(ads,-1,0,"configuration file `%s' does not exist",filename); |
| 330 | return; |
| 331 | } |
| 332 | saveerr(ads,errno); |
| 333 | adns__diag(ads,-1,0,"cannot open configuration file `%s': %s", |
| 334 | filename,strerror(errno)); |
| 335 | return; |
| 336 | } |
| 337 | |
| 338 | readconfiggeneric(ads,filename,gl_file,gl_ctx); |
| 339 | |
| 340 | fclose(gl_ctx.file); |
| 341 | } |
| 342 | |
| 343 | static void readconfigtext(adns_state ads, const char *text, const char *showname) { |
| 344 | getline_ctx gl_ctx; |
| 345 | |
| 346 | gl_ctx.text= text; |
| 347 | readconfiggeneric(ads,showname,gl_text,gl_ctx); |
| 348 | } |
| 349 | |
| 350 | static void readconfigenv(adns_state ads, const char *envvar) { |
| 351 | const char *filename; |
| 352 | |
| 353 | if (ads->iflags & adns_if_noenv) { |
| 354 | adns__debug(ads,-1,0,"not checking environment variable `%s'",envvar); |
| 355 | return; |
| 356 | } |
| 357 | filename= instrum_getenv(ads,envvar); |
| 358 | if (filename) readconfig(ads,filename); |
| 359 | } |
| 360 | |
| 361 | static void readconfigenvtext(adns_state ads, const char *envvar) { |
| 362 | const char *textdata; |
| 363 | |
| 364 | if (ads->iflags & adns_if_noenv) { |
| 365 | adns__debug(ads,-1,0,"not checking environment variable `%s'",envvar); |
| 366 | return; |
| 367 | } |
| 368 | textdata= instrum_getenv(ads,envvar); |
| 369 | if (textdata) readconfigtext(ads,textdata,envvar); |
| 370 | } |
| 371 | |
| 372 | |
| 373 | int adns__setnonblock(adns_state ads, int fd) { |
| 374 | int r; |
| 375 | |
| 376 | r= fcntl(fd,F_GETFL,0); if (r<0) return errno; |
| 377 | r |= O_NONBLOCK; |
| 378 | r= fcntl(fd,F_SETFL,r); if (r<0) return errno; |
| 379 | return 0; |
| 380 | } |
| 381 | |
| 382 | static int init_begin(adns_state *ads_r, adns_initflags flags, FILE *diagfile) { |
| 383 | adns_state ads; |
| 384 | |
| 385 | ads= malloc(sizeof(*ads)); if (!ads) return errno; |
| 386 | |
| 387 | ads->iflags= flags; |
| 388 | ads->diagfile= diagfile; |
| 389 | LIST_INIT(ads->timew); |
| 390 | LIST_INIT(ads->childw); |
| 391 | LIST_INIT(ads->output); |
| 392 | ads->nextid= 0x311f; |
| 393 | ads->udpsocket= ads->tcpsocket= -1; |
| 394 | adns__vbuf_init(&ads->tcpsend); |
| 395 | adns__vbuf_init(&ads->tcprecv); |
| 396 | ads->nservers= ads->nsortlist= ads->tcpserver= 0; |
| 397 | ads->tcpstate= server_disconnected; |
| 398 | timerclear(&ads->tcptimeout); |
| 399 | |
| 400 | *ads_r= ads; |
| 401 | return 0; |
| 402 | } |
| 403 | |
| 404 | static int init_finish(adns_state ads) { |
| 405 | struct in_addr ia; |
| 406 | struct protoent *proto; |
| 407 | int r; |
| 408 | |
| 409 | if (!ads->nservers) { |
| 410 | if (ads->diagfile && ads->iflags & adns_if_debug) |
| 411 | fprintf(ads->diagfile,"adns: no nameservers, using localhost\n"); |
| 412 | ia.s_addr= htonl(INADDR_LOOPBACK); |
| 413 | addserver(ads,ia); |
| 414 | } |
| 415 | |
| 416 | proto= getprotobyname("udp"); if (!proto) { r= ENOPROTOOPT; goto x_free; } |
| 417 | ads->udpsocket= socket(AF_INET,SOCK_DGRAM,proto->p_proto); |
| 418 | if (ads->udpsocket<0) { r= errno; goto x_free; } |
| 419 | |
| 420 | r= adns__setnonblock(ads,ads->udpsocket); |
| 421 | if (r) { r= errno; goto x_closeudp; } |
| 422 | |
| 423 | return 0; |
| 424 | |
| 425 | x_closeudp: |
| 426 | close(ads->udpsocket); |
| 427 | x_free: |
| 428 | free(ads); |
| 429 | return r; |
| 430 | } |
| 431 | |
| 432 | int adns_init(adns_state *ads_r, adns_initflags flags, FILE *diagfile) { |
| 433 | adns_state ads; |
| 434 | const char *res_options, *adns_res_options; |
| 435 | int r; |
| 436 | |
| 437 | r= init_begin(&ads, flags, diagfile ? diagfile : stderr); |
| 438 | if (r) return r; |
| 439 | |
| 440 | res_options= instrum_getenv(ads,"RES_OPTIONS"); |
| 441 | adns_res_options= instrum_getenv(ads,"ADNS_RES_OPTIONS"); |
| 442 | ccf_options(ads,"RES_OPTIONS",-1,res_options); |
| 443 | ccf_options(ads,"ADNS_RES_OPTIONS",-1,adns_res_options); |
| 444 | |
| 445 | readconfig(ads,"/etc/resolv.conf"); |
| 446 | readconfigenv(ads,"RES_CONF"); |
| 447 | readconfigenv(ads,"ADNS_RES_CONF"); |
| 448 | |
| 449 | readconfigenvtext(ads,"RES_CONF_TEXT"); |
| 450 | readconfigenvtext(ads,"ADNS_RES_CONF_TEXT"); |
| 451 | |
| 452 | ccf_options(ads,"RES_OPTIONS",-1,res_options); |
| 453 | ccf_options(ads,"ADNS_RES_OPTIONS",-1,adns_res_options); |
| 454 | |
| 455 | ccf_search(ads,"LOCALDOMAIN",-1,instrum_getenv(ads,"LOCALDOMAIN")); |
| 456 | ccf_search(ads,"ADNS_LOCALDOMAIN",-1,instrum_getenv(ads,"ADNS_LOCALDOMAIN")); |
| 457 | |
| 458 | r= init_finish(ads); |
| 459 | if (r) return r; |
| 460 | |
| 461 | *ads_r= ads; |
| 462 | return 0; |
| 463 | } |
| 464 | |
| 465 | int adns_init_strcfg(adns_state *ads_r, adns_initflags flags, |
| 466 | FILE *diagfile, const char *configtext) { |
| 467 | adns_state ads; |
| 468 | int r; |
| 469 | |
| 470 | r= init_begin(&ads, flags, diagfile); if (r) return r; |
| 471 | |
| 472 | readconfigtext(ads,configtext,"<supplied configuration text>"); |
| 473 | if (ads->configerrno) { |
| 474 | r= ads->configerrno; |
| 475 | free(ads); |
| 476 | return r; |
| 477 | } |
| 478 | |
| 479 | r= init_finish(ads); if (r) return r; |
| 480 | *ads_r= ads; |
| 481 | return 0; |
| 482 | } |
| 483 | |
| 484 | void adns_finish(adns_state ads) { |
| 485 | for (;;) { |
| 486 | if (ads->timew.head) adns_cancel(ads->timew.head); |
| 487 | else if (ads->childw.head) adns_cancel(ads->childw.head); |
| 488 | else if (ads->output.head) adns_cancel(ads->output.head); |
| 489 | else break; |
| 490 | } |
| 491 | close(ads->udpsocket); |
| 492 | if (ads->tcpsocket >= 0) close(ads->tcpsocket); |
| 493 | adns__vbuf_free(&ads->tcpsend); |
| 494 | adns__vbuf_free(&ads->tcprecv); |
| 495 | free(ads); |
| 496 | } |