mdw@git.distorted.org.uk Git - adns/blob - client/adnsheloex.c

   1 /*
   2  * adnsheloex.c
   3  * - look up the A record of hosts in an Exim log that failed HELO verification
   4  */
   5 /*
   6  *  This file is
   7  *   Copyright (C) 2004 Tony Finch <dot@dotat.at>
   8  *
   9  *  It is part of adns, which is
  10  *    Copyright (C) 1997-2000 Ian Jackson <ian@davenant.greenend.org.uk>
  11  *    Copyright (C) 1999-2004 Tony Finch <dot@dotat.at>
  12  *
  13  *  This program is free software; you can redistribute it and/or modify
  14  *  it under the terms of the GNU General Public License as published by
  15  *  the Free Software Foundation; either version 2, or (at your option)
  16  *  any later version.
  17  *
  18  *  This program is distributed in the hope that it will be useful,
  19  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21  *  GNU General Public License for more details.
  22  *
  23  *  You should have received a copy of the GNU General Public License
  24  *  along with this program; if not, write to the Free Software Foundation,
  25  *  Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  26  *
  27  *  This file is by Tony Finch, based on adnslogres.c.
  28  */
  29
  30 static const char * const cvsid =
  31         "$Id$";
  32
  33 #include <sys/types.h>
  34 #include <sys/socket.h>
  35 #include <sys/time.h>
  36
  37 #include <netinet/in.h>
  38 #include <arpa/inet.h>
  39
  40 #include <unistd.h>
  41 #include <string.h>
  42 #include <stdlib.h>
  43 #include <stdio.h>
  44 #include <ctype.h>
  45 #include <errno.h>
  46 #include <stdarg.h>
  47
  48 #include "config.h"
  49 #include "adns.h"
  50 #include "client.h"
  51
  52 #ifdef ADNS_REGRESS_TEST
  53 # include "hredirect.h"
  54 #endif
  55
  56 /* maximum number of concurrent DNS queries */
  57 #define MAXMAXPENDING 64000
  58 #define DEFMAXPENDING 2000
  59
  60 /* maximum length of a line */
  61 #define MAXLINE 1024
  62
  63 /* option flags */
  64 #define OPT_DEBUG 1
  65 #define OPT_POLL 2
  66
  67 static const char *const progname= "adnsheloex";
  68 static const char *config_text;
  69
  70 #define guard_null(str) ((str) ? (str) : "")
  71
  72 #define sensible_ctype(type,ch) (type((unsigned char)(ch)))
  73   /* isfoo() functions from ctype.h can't safely be fed char - blech ! */
  74
  75 static void msg(const char *fmt, ...) {
  76   va_list al;
  77
  78   fprintf(stderr, "%s: ", progname);
  79   va_start(al,fmt);
  80   vfprintf(stderr, fmt, al);
  81   va_end(al);
  82   fputc('\n',stderr);
  83 }
  84
  85 static void aargh(const char *cause) {
  86   const char *why = strerror(errno);
  87   if (!why) why = "Unknown error";
  88   msg("%s: %s (%d)", cause, why, errno);
  89   exit(1);
  90 }
  91
  92 typedef struct logline {
  93   struct logline *next;
  94   char *start, *name, *rest, *addr;
  95   adns_query query;
  96 } logline;
  97
  98 static logline *readline(FILE *inf, adns_state adns, int opts) {
  99   static char buf[MAXLINE];
 100   char *str, *p, *q, *r;
 101   logline *line;
 102
 103   if (fgets(buf, MAXLINE, inf)) {
 104     str= malloc(sizeof(*line) + strlen(buf) + 1);
 105     if (!str) aargh("malloc");
 106     line= (logline*)str;
 107     line->next= NULL;
 108     line->start= str+sizeof(logline);
 109     strcpy(line->start, buf);
 110     line->name= line->rest= line->addr= NULL;
 111     /* look for unverifiable HELO information matching the regex
 112        H=[a-z0-9.- ]*[(][a-z0-9.-]*[)] [[][0-9.]*[]] */
 113     for (p= strchr(line->start, ' '); p; p= strchr(p+1, ' ')) {
 114       if (!strncmp(p, " H=", 3)) {
 115         r= strchr(p, '[');
 116         if (!r) break;
 117         q= strchr(p, ')');
 118         if (!q || q>r) break;
 119         p= strchr(p, '(');
 120         if (!p || p>q) break;
 121         line->name= p+1;
 122         line->rest= q;
 123         line->addr= r+1;
 124         break;
 125       }
 126     }
 127     if (line->name) {
 128       *line->rest= '\0';
 129       if (opts & OPT_DEBUG)
 130         msg("submitting %s", line->name);
 131       if (adns_submit(adns, line->name, adns_r_a,
 132                       adns_qf_quoteok_query|adns_qf_quoteok_cname|adns_qf_cname_loose,
 133                       NULL, &line->query))
 134         aargh("adns_submit");
 135       *line->rest= ')';
 136     } else {
 137       if (opts & OPT_DEBUG)
 138         msg("no query");
 139       line->query= NULL;
 140     }
 141     return line;
 142   }
 143   if (!feof(inf))
 144     aargh("fgets");
 145   return NULL;
 146 }
 147
 148 static void proclog(FILE *inf, FILE *outf, int maxpending, int opts) {
 149   int eof, err, len;
 150   adns_state adns;
 151   adns_answer *answer;
 152   logline *head, *tail, *line;
 153   adns_initflags initflags;
 154
 155   initflags= (opts & OPT_DEBUG) ? adns_if_debug : 0;
 156   if (config_text) {
 157     errno= adns_init_strcfg(&adns, initflags, stderr, config_text);
 158   } else {
 159     errno= adns_init(&adns, initflags, 0);
 160   }
 161   if (errno) aargh("adns_init");
 162   head= tail= readline(inf, adns, opts);
 163   len= 1; eof= 0;
 164   while (head) {
 165     while (head) {
 166       if (head->query) {
 167         if (opts & OPT_DEBUG)
 168           msg("%d in queue; checking %.*s", len,
 169               head->rest-head->name, guard_null(head->name));
 170         if (eof || len >= maxpending) {
 171           if (opts & OPT_POLL)
 172             err= adns_wait_poll(adns, &head->query, &answer, NULL);
 173           else
 174             err= adns_wait(adns, &head->query, &answer, NULL);
 175         } else {
 176           err= adns_check(adns, &head->query, &answer, NULL);
 177         }
 178         if (err == EAGAIN) break;
 179         if (err) {
 180           fprintf(stderr, "%s: adns_wait/check: %s", progname, strerror(err));
 181           exit(1);
 182         }
 183         if (answer->status == adns_s_ok) {
 184           const char *addr;
 185           int ok = 0;
 186           fprintf(outf, "%.*s", head->rest-head->start, head->start);
 187           while(answer->nrrs--) {
 188             addr= inet_ntoa(answer->rrs.inaddr[answer->nrrs]);
 189             ok |= !strncmp(addr, head->addr, strlen(addr));
 190             fprintf(outf, " [%s]", addr);
 191           }
 192           fprintf(outf, "%s%s", ok ? " OK" : "", head->rest);
 193         } else {
 194           if (opts & OPT_DEBUG)
 195             msg("query failed");
 196           fputs(head->start, outf);
 197         }
 198         free(answer);
 199         len--;
 200       } else {
 201         if (opts & OPT_DEBUG)
 202           msg("%d in queue; no query on this line", len);
 203         fputs(head->start, outf);
 204       }
 205       line= head; head= head->next;
 206       free(line);
 207     }
 208     if (!eof) {
 209       line= readline(inf, adns, opts);
 210       if (line) {
 211         if (!head) head= line;
 212         else tail->next= line;
 213         tail= line;
 214         if (line->query) len++;
 215       } else {
 216         eof= 1;
 217       }
 218     }
 219   }
 220   adns_finish(adns);
 221 }
 222
 223 static void printhelp(FILE *file) {
 224   fputs("usage: adnsheloex [<options>] [<logfile>]\n"
 225         "       adnsheloex --version|--help\n"
 226         "options: -c <concurrency>  set max number of outstanding queries\n"
 227         "         -p                use poll(2) instead of select(2)\n"
 228         "         -d                turn on debugging\n"
 229         "         -C <config>       use instead of contents of resolv.conf\n",
 230         stdout);
 231 }
 232
 233 static void usage(void) {
 234   printhelp(stderr);
 235   exit(1);
 236 }
 237
 238 int main(int argc, char *argv[]) {
 239   int c, opts, maxpending;
 240   extern char *optarg;
 241   FILE *inf;
 242
 243   if (argv[1] && !strncmp(argv[1],"--",2)) {
 244     if (!strcmp(argv[1],"--help")) {
 245       printhelp(stdout);
 246     } else if (!strcmp(argv[1],"--version")) {
 247       fputs(VERSION_MESSAGE("adnsheloex"),stdout);
 248     } else {
 249       usage();
 250     }
 251     if (ferror(stdout) || fclose(stdout)) { perror("stdout"); exit(1); }
 252     exit(0);
 253   }
 254
 255   maxpending= DEFMAXPENDING;
 256   opts= 0;
 257   while ((c= getopt(argc, argv, "c:C:dp")) != -1)
 258     switch (c) {
 259     case 'c':
 260       maxpending= atoi(optarg);
 261       if (maxpending < 1 || maxpending > MAXMAXPENDING) {
 262        fprintf(stderr, "%s: unfeasible concurrency %d\n", progname, maxpending);
 263        exit(1);
 264       }
 265       break;
 266     case 'C':
 267       config_text= optarg;
 268       break;
 269     case 'd':
 270       opts|= OPT_DEBUG;
 271       break;
 272     case 'p':
 273       opts|= OPT_POLL;
 274       break;
 275     default:
 276       usage();
 277     }
 278
 279   argc-= optind;
 280   argv+= optind;
 281
 282   inf= NULL;
 283   if (argc == 0)
 284     inf= stdin;
 285   else if (argc == 1)
 286     inf= fopen(*argv, "r");
 287   else
 288     usage();
 289
 290   if (!inf)
 291     aargh("couldn't open input");
 292
 293   proclog(inf, stdout, maxpending, opts);
 294
 295   if (fclose(inf))
 296     aargh("fclose input");
 297   if (fclose(stdout))
 298     aargh("fclose output");
 299
 300   return 0;
 301 }