1 #include <u.h> 2 #include <libc.h> 3 #include <bio.h> 4 #include <ctype.h> 5 #include <ip.h> 6 #include <ndb.h> 7 #include "dns.h" 8 9 enum 10 { 11 Maxrequest= 128, 12 Ncache= 8, 13 Maxpath= 128, 14 Maxreply= 512, 15 Maxrrr= 16, 16 }; 17 18 static char *servername; 19 static RR *serverrr; 20 static RR *serveraddrs; 21 22 int debug; 23 int cachedb; 24 ulong now; 25 int testing; 26 char *trace; 27 int needrefresh; 28 int resolver; 29 uchar ipaddr[IPaddrlen]; /* my ip address */ 30 int maxage; 31 char *logfile = "dns"; 32 char *dbfile; 33 char mntpt[Maxpath]; 34 char *zonerefreshprogram; 35 36 int prettyrrfmt(Fmt*); 37 void preloadserveraddrs(void); 38 void squirrelserveraddrs(void); 39 int setserver(char*); 40 void doquery(char*, char*); 41 void docmd(int, char**); 42 43 void 44 main(int argc, char *argv[]) 45 { 46 int n; 47 Biobuf in; 48 char *p; 49 char *f[4]; 50 51 strcpy(mntpt, "/net"); 52 53 ARGBEGIN{ 54 case 'r': 55 resolver = 1; 56 break; 57 case 'x': 58 dbfile = "/lib/ndb/external"; 59 strcpy(mntpt, "/net.alt"); 60 break; 61 }ARGEND 62 63 now = time(0); 64 dninit(); 65 fmtinstall('R', prettyrrfmt); 66 if(myipaddr(ipaddr, mntpt) < 0) 67 sysfatal("can't read my ip address"); 68 opendatabase(); 69 70 if(resolver) 71 squirrelserveraddrs(); 72 73 debug = 1; 74 75 if(argc > 0){ 76 docmd(argc, argv); 77 exits(0); 78 } 79 80 Binit(&in, 0, OREAD); 81 for(print("> "); p = Brdline(&in, '\n'); print("> ")){ 82 p[Blinelen(&in)-1] = 0; 83 n = tokenize(p, f, 3); 84 if(n<1) 85 continue; 86 87 /* flush the cache */ 88 dnpurge(); 89 90 docmd(n, f); 91 92 } 93 exits(0); 94 } 95 96 static char* 97 longtime(long t) 98 { 99 int d, h, m, n; 100 static char x[128]; 101 102 for(d = 0; t >= 24*60*60; t -= 24*60*60) 103 d++; 104 for(h = 0; t >= 60*60; t -= 60*60) 105 h++; 106 for(m = 0; t >= 60; t -= 60) 107 m++; 108 n = 0; 109 if(d) 110 n += sprint(x, "%d day ", d); 111 if(h) 112 n += sprint(x+n, "%d hr ", h); 113 if(m) 114 n += sprint(x+n, "%d min ", m); 115 if(t || n == 0) 116 sprint(x+n, "%ld sec", t); 117 return x; 118 } 119 120 int 121 prettyrrfmt(Fmt *f) 122 { 123 RR *rp; 124 char buf[3*Domlen]; 125 char *p, *e; 126 127 rp = va_arg(f->args, RR*); 128 if(rp == 0){ 129 strcpy(buf, "<null>"); 130 goto out; 131 } 132 133 p = buf; 134 e = buf + sizeof(buf); 135 p = seprint(p, e, "%-32.32s %-15.15s %-5.5s", rp->owner->name, 136 longtime(rp->db ? rp->ttl : (rp->ttl-now)), 137 rrname(rp->type, buf, sizeof buf)); 138 139 if(rp->negative){ 140 seprint(p, e, "negative rcode %d\n", rp->negrcode); 141 goto out; 142 } 143 144 switch(rp->type){ 145 case Thinfo: 146 seprint(p, e, "\t%s %s", rp->cpu->name, rp->os->name); 147 break; 148 case Tcname: 149 case Tmb: 150 case Tmd: 151 case Tmf: 152 case Tns: 153 seprint(p, e, "\t%s", rp->host->name); 154 break; 155 case Tmg: 156 case Tmr: 157 seprint(p, e, "\t%s", rp->mb->name); 158 break; 159 case Tminfo: 160 seprint(p, e, "\t%s %s", rp->mb->name, rp->rmb->name); 161 break; 162 case Tmx: 163 seprint(p, e, "\t%lud %s", rp->pref, rp->host->name); 164 break; 165 case Ta: 166 case Taaaa: 167 seprint(p, e, "\t%s", rp->ip->name); 168 break; 169 case Tptr: 170 seprint(p, e, "\t%s", rp->ptr->name); 171 break; 172 case Tsoa: 173 seprint(p, e, "\t%s %s %lud %lud %lud %lud %lud", rp->host->name, 174 rp->rmb->name, rp->soa->serial, rp->soa->refresh, rp->soa->retry, 175 rp->soa->expire, rp->soa->minttl); 176 break; 177 case Tnull: 178 seprint(p, e, "\t%.*H", rp->null->dlen, rp->null->data); 179 break; 180 case Ttxt: 181 seprint(p, e, "\t%s", rp->txt->name); 182 break; 183 case Trp: 184 seprint(p, e, "\t%s %s", rp->rmb->name, rp->txt->name); 185 break; 186 case Tkey: 187 seprint(p, e, "\t%d %d %d", rp->key->flags, rp->key->proto, 188 rp->key->alg); 189 break; 190 case Tsig: 191 seprint(p, e, "\t%d %d %d %lud %lud %lud %d %s", 192 rp->sig->type, rp->sig->alg, rp->sig->labels, rp->sig->ttl, 193 rp->sig->exp, rp->sig->incep, rp->sig->tag, rp->sig->signer->name); 194 break; 195 case Tcert: 196 seprint(p, e, "\t%d %d %d", 197 rp->sig->type, rp->sig->tag, rp->sig->alg); 198 break; 199 default: 200 break; 201 } 202 out: 203 return fmtstrcpy(f, buf); 204 } 205 206 void 207 logsection(char *flag, RR *rp) 208 { 209 if(rp == nil) 210 return; 211 print("\t%s%R\n", flag, rp); 212 for(rp = rp->next; rp != nil; rp = rp->next) 213 print("\t %R\n", rp); 214 } 215 216 void 217 logreply(int id, uchar *addr, DNSmsg *mp) 218 { 219 RR *rp; 220 char buf[12]; 221 char resp[32]; 222 223 switch(mp->flags & Rmask){ 224 case Rok: 225 strcpy(resp, "OK"); 226 break; 227 case Rformat: 228 strcpy(resp, "Format error"); 229 break; 230 case Rserver: 231 strcpy(resp, "Server failed"); 232 break; 233 case Rname: 234 strcpy(resp, "Nonexistent"); 235 break; 236 case Runimplimented: 237 strcpy(resp, "Unimplemented"); 238 break; 239 case Rrefused: 240 strcpy(resp, "Refused"); 241 break; 242 default: 243 sprint(resp, "%d", mp->flags & Rmask); 244 break; 245 } 246 247 print("%d: rcvd %s from %I (%s%s%s%s%s)\n", id, resp, addr, 248 mp->flags & Fauth ? "authoritative" : "", 249 mp->flags & Ftrunc ? " truncated" : "", 250 mp->flags & Frecurse ? " recurse" : "", 251 mp->flags & Fcanrec ? " can_recurse" : "", 252 mp->flags & (Fauth|Rname) == (Fauth|Rname) ? 253 " nx" : ""); 254 for(rp = mp->qd; rp != nil; rp = rp->next) 255 print("\tQ: %s %s\n", rp->owner->name, rrname(rp->type, buf, sizeof buf)); 256 logsection("Ans: ", mp->an); 257 logsection("Auth: ", mp->ns); 258 logsection("Hint: ", mp->ar); 259 } 260 261 void 262 logsend(int id, int subid, uchar *addr, char *sname, char *rname, int type) 263 { 264 char buf[12]; 265 266 print("%d.%d: sending to %I/%s %s %s\n", id, subid, 267 addr, sname, rname, rrname(type, buf, sizeof buf)); 268 } 269 270 RR* 271 getdnsservers(int class) 272 { 273 RR *rr; 274 275 if(servername == nil) 276 return dnsservers(class); 277 278 rr = rralloc(Tns); 279 rr->owner = dnlookup("local#dns#servers", class, 1); 280 rr->host = dnlookup(servername, class, 1); 281 282 return rr; 283 } 284 285 void 286 squirrelserveraddrs(void) 287 { 288 RR *rr, *rp, **l; 289 Request req; 290 291 /* look up the resolver address first */ 292 resolver = 0; 293 debug = 0; 294 if(serveraddrs) 295 rrfreelist(serveraddrs); 296 serveraddrs = nil; 297 rr = getdnsservers(Cin); 298 l = &serveraddrs; 299 for(rp = rr; rp != nil; rp = rp->next){ 300 if(strcmp(ipattr(rp->host->name), "ip") == 0){ 301 *l = rralloc(Ta); 302 (*l)->owner = rp->host; 303 (*l)->ip = rp->host; 304 l = &(*l)->next; 305 continue; 306 } 307 req.isslave = 1; 308 req.aborttime = now + 60; /* don't spend more than 60 seconds */ 309 *l = dnresolve(rp->host->name, Cin, Ta, &req, 0, 0, Recurse, 0, 0); 310 while(*l != nil) 311 l = &(*l)->next; 312 } 313 resolver = 1; 314 debug = 1; 315 } 316 317 void 318 preloadserveraddrs(void) 319 { 320 RR *rp, **l, *first; 321 322 l = &first; 323 for(rp = serveraddrs; rp != nil; rp = rp->next){ 324 rrcopy(rp, l); 325 rrattach(first, 1); 326 } 327 } 328 329 int 330 setserver(char *server) 331 { 332 if(servername != nil){ 333 free(servername); 334 servername = nil; 335 resolver = 0; 336 } 337 if(server == nil || *server == 0) 338 return 0; 339 servername = strdup(server); 340 squirrelserveraddrs(); 341 if(serveraddrs == nil){ 342 print("can't resolve %s\n", servername); 343 resolver = 0; 344 } else { 345 resolver = 1; 346 } 347 return resolver ? 0 : -1; 348 } 349 350 void 351 doquery(char *name, char *tstr) 352 { 353 Request req; 354 RR *rr, *rp; 355 int len, type; 356 char *p, *np; 357 int rooted; 358 char buf[1024]; 359 360 if(resolver) 361 preloadserveraddrs(); 362 363 /* default to an "ip" request if alpha, "ptr" if numeric */ 364 if(tstr == nil || *tstr == 0) { 365 if(strcmp(ipattr(name), "ip") == 0) 366 tstr = "ptr"; 367 else 368 tstr = "ip"; 369 } 370 371 /* if name end in '.', remove it */ 372 len = strlen(name); 373 if(len > 0 && name[len-1] == '.'){ 374 rooted = 1; 375 name[len-1] = 0; 376 } else 377 rooted = 0; 378 379 /* inverse queries may need to be permuted */ 380 strncpy(buf, name, sizeof buf); 381 if(strcmp("ptr", tstr) == 0 382 && strstr(name, "IN-ADDR") == 0 383 && strstr(name, "in-addr") == 0){ 384 for(p = name; *p; p++) 385 ; 386 *p = '.'; 387 np = buf; 388 len = 0; 389 while(p >= name){ 390 len++; 391 p--; 392 if(*p == '.'){ 393 memmove(np, p+1, len); 394 np += len; 395 len = 0; 396 } 397 } 398 memmove(np, p+1, len); 399 np += len; 400 strcpy(np, "in-addr.arpa"); 401 } 402 403 /* look it up */ 404 type = rrtype(tstr); 405 if(type < 0){ 406 print("!unknown type %s\n", tstr); 407 return; 408 } 409 410 getactivity(&req); 411 req.isslave = 1; 412 req.aborttime = now + 60; /* don't spend more than 60 seconds */ 413 rr = dnresolve(buf, Cin, type, &req, 0, 0, Recurse, rooted, 0); 414 if(rr){ 415 print("----------------------------\n"); 416 for(rp = rr; rp; rp = rp->next) 417 print("answer %R\n", rp); 418 print("----------------------------\n"); 419 } 420 rrfreelist(rr); 421 422 putactivity(); 423 } 424 425 void 426 docmd(int n, char **f) 427 { 428 int tmpsrv; 429 char *name, *type; 430 431 name = nil; 432 type = nil; 433 tmpsrv = 0; 434 435 if(*f[0] == '@') { 436 if(setserver(f[0]+1) < 0) 437 return; 438 439 switch(n){ 440 case 3: 441 type = f[2]; 442 /* fall through */ 443 case 2: 444 name = f[1]; 445 tmpsrv = 1; 446 break; 447 } 448 } else { 449 switch(n){ 450 case 2: 451 type = f[1]; 452 /* fall through */ 453 case 1: 454 name = f[0]; 455 break; 456 } 457 } 458 459 if(name == nil) 460 return; 461 462 doquery(name, type); 463 464 if(tmpsrv) 465 setserver(""); 466 } 467