| 1 | /* |
| 2 | * general.c |
| 3 | * - diagnostic functions |
| 4 | * - vbuf handling |
| 5 | */ |
| 6 | /* |
| 7 | * This file is part of adns, which is Copyright (C) 1997-1999 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 <string.h> |
| 26 | |
| 27 | #include <arpa/inet.h> |
| 28 | |
| 29 | #include "internal.h" |
| 30 | |
| 31 | /* Core diagnostic functions */ |
| 32 | |
| 33 | void adns__vdiag(adns_state ads, const char *pfx, adns_initflags prevent, |
| 34 | int serv, adns_query qu, const char *fmt, va_list al) { |
| 35 | const char *bef, *aft; |
| 36 | vbuf vb; |
| 37 | |
| 38 | if (!ads->diagfile || |
| 39 | (!(ads->iflags & adns_if_debug) && (!prevent || (ads->iflags & prevent)))) |
| 40 | return; |
| 41 | |
| 42 | fprintf(ads->diagfile,"adns%s: ",pfx); |
| 43 | |
| 44 | vfprintf(ads->diagfile,fmt,al); |
| 45 | |
| 46 | bef= " ("; |
| 47 | aft= "\n"; |
| 48 | |
| 49 | if (qu && qu->query_dgram) { |
| 50 | adns__vbuf_init(&vb); |
| 51 | fprintf(ads->diagfile,"%sQNAME=%s, QTYPE=%s", |
| 52 | bef, |
| 53 | adns__diag_domain(qu->ads,-1,0, &vb, |
| 54 | qu->query_dgram,qu->query_dglen,DNS_HDRSIZE), |
| 55 | qu->typei ? qu->typei->rrtname : "<unknown>"); |
| 56 | if (qu->typei && qu->typei->fmtname) |
| 57 | fprintf(ads->diagfile,"(%s)",qu->typei->fmtname); |
| 58 | bef=", "; aft=")\n"; |
| 59 | } |
| 60 | |
| 61 | if (serv>=0) { |
| 62 | fprintf(ads->diagfile,"%sNS=%s",bef,inet_ntoa(ads->servers[serv].addr)); |
| 63 | bef=", "; aft=")\n"; |
| 64 | } |
| 65 | |
| 66 | fputs(aft,ads->diagfile); |
| 67 | } |
| 68 | |
| 69 | void adns__debug(adns_state ads, int serv, adns_query qu, const char *fmt, ...) { |
| 70 | va_list al; |
| 71 | |
| 72 | va_start(al,fmt); |
| 73 | adns__vdiag(ads," debug",0,serv,qu,fmt,al); |
| 74 | va_end(al); |
| 75 | } |
| 76 | |
| 77 | void adns__warn(adns_state ads, int serv, adns_query qu, const char *fmt, ...) { |
| 78 | va_list al; |
| 79 | |
| 80 | va_start(al,fmt); |
| 81 | adns__vdiag(ads," warning",adns_if_noerrprint|adns_if_noserverwarn,serv,qu,fmt,al); |
| 82 | va_end(al); |
| 83 | } |
| 84 | |
| 85 | void adns__diag(adns_state ads, int serv, adns_query qu, const char *fmt, ...) { |
| 86 | va_list al; |
| 87 | |
| 88 | va_start(al,fmt); |
| 89 | adns__vdiag(ads,"",adns_if_noerrprint,serv,qu,fmt,al); |
| 90 | va_end(al); |
| 91 | } |
| 92 | |
| 93 | /* vbuf functions */ |
| 94 | |
| 95 | void adns__vbuf_init(vbuf *vb) { |
| 96 | vb->used= vb->avail= 0; vb->buf= 0; |
| 97 | } |
| 98 | |
| 99 | int adns__vbuf_ensure(vbuf *vb, int want) { |
| 100 | void *nb; |
| 101 | |
| 102 | if (vb->avail >= want) return 1; |
| 103 | nb= realloc(vb->buf,want); if (!nb) return 0; |
| 104 | vb->buf= nb; |
| 105 | vb->avail= want; |
| 106 | return 1; |
| 107 | } |
| 108 | |
| 109 | void adns__vbuf_appendq(vbuf *vb, const byte *data, int len) { |
| 110 | memcpy(vb->buf+vb->used,data,len); |
| 111 | vb->used+= len; |
| 112 | } |
| 113 | |
| 114 | int adns__vbuf_append(vbuf *vb, const byte *data, int len) { |
| 115 | int newlen; |
| 116 | void *nb; |
| 117 | |
| 118 | newlen= vb->used+len; |
| 119 | if (vb->avail < newlen) { |
| 120 | if (newlen<20) newlen= 20; |
| 121 | newlen <<= 1; |
| 122 | nb= realloc(vb->buf,newlen); |
| 123 | if (!nb) { newlen= vb->used+len; nb= realloc(vb->buf,newlen); } |
| 124 | if (!nb) return 0; |
| 125 | vb->buf= nb; |
| 126 | vb->avail= newlen; |
| 127 | } |
| 128 | adns__vbuf_appendq(vb,data,len); |
| 129 | return 1; |
| 130 | } |
| 131 | |
| 132 | int adns__vbuf_appendstr(vbuf *vb, const char *data) { |
| 133 | int l; |
| 134 | l= strlen(data); |
| 135 | return adns__vbuf_append(vb,data,l); |
| 136 | } |
| 137 | |
| 138 | void adns__vbuf_free(vbuf *vb) { |
| 139 | free(vb->buf); |
| 140 | adns__vbuf_init(vb); |
| 141 | } |
| 142 | |
| 143 | /* Additional diagnostic functions */ |
| 144 | |
| 145 | const char *adns__diag_domain(adns_state ads, int serv, adns_query qu, |
| 146 | vbuf *vb, const byte *dgram, int dglen, int cbyte) { |
| 147 | adns_status st; |
| 148 | |
| 149 | st= adns__parse_domain(ads,serv,qu,vb, pdf_quoteok, dgram,dglen,&cbyte,dglen); |
| 150 | if (st == adns_s_nomemory) { |
| 151 | return "<cannot report domain... out of memory>"; |
| 152 | } |
| 153 | if (st) { |
| 154 | vb->used= 0; |
| 155 | if (!(adns__vbuf_appendstr(vb,"<bad format... ") && |
| 156 | adns__vbuf_appendstr(vb,adns_strerror(st)) && |
| 157 | adns__vbuf_appendstr(vb,">") && |
| 158 | adns__vbuf_append(vb,"",1))) { |
| 159 | return "<cannot report bad format... out of memory>"; |
| 160 | } |
| 161 | } |
| 162 | if (!vb->used) { |
| 163 | adns__vbuf_appendstr(vb,"<truncated ...>"); |
| 164 | adns__vbuf_append(vb,"",1); |
| 165 | } |
| 166 | return vb->buf; |
| 167 | } |
| 168 | |
| 169 | adns_status adns_rr_info(adns_rrtype type, |
| 170 | const char **rrtname_r, const char **fmtname_r, |
| 171 | int *len_r, |
| 172 | const void *datap, char **data_r) { |
| 173 | const typeinfo *typei; |
| 174 | vbuf vb; |
| 175 | adns_status st; |
| 176 | |
| 177 | typei= adns__findtype(type); |
| 178 | if (!typei) return adns_s_unknownrrtype; |
| 179 | |
| 180 | if (rrtname_r) *rrtname_r= typei->rrtname; |
| 181 | if (fmtname_r) *fmtname_r= typei->fmtname; |
| 182 | if (len_r) *len_r= typei->rrsz; |
| 183 | |
| 184 | if (!datap) return adns_s_ok; |
| 185 | |
| 186 | adns__vbuf_init(&vb); |
| 187 | st= typei->convstring(&vb,datap); |
| 188 | if (st) goto x_freevb; |
| 189 | if (!adns__vbuf_append(&vb,"",1)) { st= adns_s_nomemory; goto x_freevb; } |
| 190 | assert(strlen(vb.buf) == vb.used-1); |
| 191 | *data_r= realloc(vb.buf,vb.used); |
| 192 | if (!*data_r) *data_r= vb.buf; |
| 193 | return adns_s_ok; |
| 194 | |
| 195 | x_freevb: |
| 196 | adns__vbuf_free(&vb); |
| 197 | return st; |
| 198 | } |
| 199 | |
| 200 | #define SINFO(n,s) { adns_s_##n, s } |
| 201 | |
| 202 | static const struct sinfo { |
| 203 | adns_status st; |
| 204 | const char *string; |
| 205 | } sinfos[]= { |
| 206 | SINFO( ok, "OK" ), |
| 207 | |
| 208 | SINFO( nomemory, "Out of memory" ), |
| 209 | SINFO( unknownrrtype, "Query not implemented in DNS library" ), |
| 210 | |
| 211 | SINFO( timeout, "DNS query timed out" ), |
| 212 | SINFO( allservfail, "All nameservers failed" ), |
| 213 | SINFO( norecurse, "Recursion denied by nameserver" ), |
| 214 | SINFO( invalidresponse, "Nameserver sent bad response" ), |
| 215 | SINFO( unknownformat, "Nameserver used unknown format" ), |
| 216 | |
| 217 | SINFO( rcodeservfail, "Nameserver reports failure" ), |
| 218 | SINFO( rcodeformaterror, "Query not understood by nameserver" ), |
| 219 | SINFO( rcodenotimplemented, "Query not implemented by nameserver" ), |
| 220 | SINFO( rcoderefused, "Query refused by nameserver" ), |
| 221 | SINFO( rcodeunknown, "Nameserver sent unknown response code" ), |
| 222 | |
| 223 | SINFO( inconsistent, "Inconsistent resource records in DNS" ), |
| 224 | SINFO( prohibitedcname, "DNS data refers to an alias" ), |
| 225 | SINFO( answerdomaininvalid, "Found syntactically invalid domain name" ), |
| 226 | SINFO( answerdomaintoolong, "Found overly-long domain name" ), |
| 227 | SINFO( invaliddata, "Found invalid DNS data" ), |
| 228 | |
| 229 | SINFO( querydomainwrong, "Domain invalid for particular DNS query type" ), |
| 230 | SINFO( querydomaininvalid, "Domain name is syntactically invalid" ), |
| 231 | SINFO( querydomaintoolong, "Domain name is too long" ), |
| 232 | |
| 233 | SINFO( nxdomain, "No such domain" ), |
| 234 | SINFO( nodata, "No such data" ), |
| 235 | }; |
| 236 | |
| 237 | static int si_compar(const void *key, const void *elem) { |
| 238 | const adns_status *st= key; |
| 239 | const struct sinfo *si= elem; |
| 240 | |
| 241 | return *st < si->st ? -1 : *st > si->st ? 1 : 0; |
| 242 | } |
| 243 | |
| 244 | const char *adns_strerror(adns_status st) { |
| 245 | static char buf[100]; |
| 246 | |
| 247 | const struct sinfo *si; |
| 248 | |
| 249 | si= bsearch(&st,sinfos,sizeof(sinfos)/sizeof(*si),sizeof(*si),si_compar); |
| 250 | if (si) return si->string; |
| 251 | |
| 252 | snprintf(buf,sizeof(buf),"code %d",st); |
| 253 | return buf; |
| 254 | } |
| 255 | |
| 256 | void adns__isort(void *array, int nobjs, int sz, void *tempbuf, |
| 257 | int (*needswap)(void *context, const void *a, const void *b), |
| 258 | void *context) { |
| 259 | byte *data= array; |
| 260 | int i, place; |
| 261 | |
| 262 | for (i=0; i<nobjs; i++) { |
| 263 | for (place= i; |
| 264 | place>0 && needswap(context, data + (place-1)*sz, data + i*sz); |
| 265 | place--); |
| 266 | if (place != i) { |
| 267 | memcpy(tempbuf, data + i*sz, sz); |
| 268 | memmove(data + (place+1)*sz, data + place*sz, (i-place)*sz); |
| 269 | memcpy(data + place*sz, tempbuf, sz); |
| 270 | } |
| 271 | } |
| 272 | } |
| 273 | |
| 274 | /* SIGPIPE protection. */ |
| 275 | |
| 276 | void adns__sigpipe_protect(adns_state ads) { |
| 277 | sigset_t toblock; |
| 278 | struct sigaction sa; |
| 279 | int r; |
| 280 | |
| 281 | if (ads->iflags & adns_if_nosigpipe) return; |
| 282 | |
| 283 | sigfillset(&toblock); |
| 284 | sigdelset(&toblock,SIGPIPE); |
| 285 | |
| 286 | sa.sa_handler= SIG_IGN; |
| 287 | sigfillset(&sa.sa_mask); |
| 288 | sa.sa_flags= 0; |
| 289 | |
| 290 | r= sigprocmask(SIG_SETMASK,&toblock,&ads->stdsigmask); assert(!r); |
| 291 | r= sigaction(SIGPIPE,&sa,&ads->stdsigpipe); assert(!r); |
| 292 | } |
| 293 | |
| 294 | void adns__sigpipe_unprotect(adns_state ads) { |
| 295 | int r; |
| 296 | |
| 297 | if (ads->iflags & adns_if_nosigpipe) return; |
| 298 | |
| 299 | r= sigaction(SIGPIPE,&ads->stdsigpipe,0); assert(!r); |
| 300 | r= sigprocmask(SIG_SETMASK,&ads->stdsigmask,0); assert(!r); |
| 301 | } |