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) 1997-2000,2003,2006,2014  Ian Jackson
  11  *    Copyright (C) 1999-2000,2003,2006  Tony Finch
  12  *    Copyright (C) 1991 Massachusetts Institute of Technology
  13  *  (See the file INSTALL for full details.)
  14  *
  15  *  This program is free software; you can redistribute it and/or modify
  16  *  it under the terms of the GNU General Public License as published by
  17  *  the Free Software Foundation; either version 3, or (at your option)
  18  *  any later version.
  19  *
  20  *  This program is distributed in the hope that it will be useful,
  21  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  22  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  23  *  GNU General Public License for more details.
  24  *
  25  *  You should have received a copy of the GNU General Public License
  26  *  along with this program; if not, write to the Free Software Foundation.
  27  *
  28  *  This file is by Tony Finch, based on adnslogres.c.
  29  */
  30
  31 static const char * const cvsid =
  32         "$Id$";
  33
  34 #include <sys/types.h>
  35 #include <sys/socket.h>
  36 #include <sys/time.h>
  37
  38 #include <netinet/in.h>
  39 #include <arpa/inet.h>
  40
  41 #include <unistd.h>
  42 #include <string.h>
  43 #include <stdlib.h>
  44 #include <stdio.h>
  45 #include <ctype.h>
  46 #include <errno.h>
  47 #include <stdarg.h>
  48
  49 #include "config.h"
  50 #include "adns.h"
  51 #include "client.h"
  52
  53 #ifdef ADNS_REGRESS_TEST
  54 # include "hredirect.h"
  55 #endif
  56
  57 /* maximum number of concurrent DNS queries */
  58 #define MAXMAXPENDING 64000
  59 #define DEFMAXPENDING 2000
  60
  61 /* maximum length of a line */
  62 #define MAXLINE 1024
  63
  64 /* option flags */
  65 #define OPT_DEBUG 1
  66 #define OPT_POLL 2
  67
  68 static const char *const progname= "adnsheloex";
  69 static const char *config_text;
  70
  71 #define guard_null(str) ((str) ? (str) : "")
  72
  73 #define sensible_ctype(type,ch) (type((unsigned char)(ch)))
  74   /* isfoo() functions from ctype.h can't safely be fed char - blech ! */
  75
  76 static void msg(const char *fmt, ...) {
  77   va_list al;
  78
  79   fprintf(stderr, "%s: ", progname);
  80   va_start(al,fmt);
  81   vfprintf(stderr, fmt, al);
  82   va_end(al);
  83   fputc('\n',stderr);
  84 }
  85
  86 static void aargh(const char *cause) {
  87   const char *why = strerror(errno);
  88   if (!why) why = "Unknown error";
  89   msg("%s: %s (%d)", cause, why, errno);
  90   exit(1);
  91 }
  92
  93 typedef struct logline {
  94   struct logline *next;
  95   char *start, *name, *rest, *addr;
  96   adns_query query;
  97 } logline;
  98
  99 static logline *readline(FILE *inf, adns_state adns, int opts) {
 100   static char buf[MAXLINE];
 101   char *str, *p, *q, *r;
 102   logline *line;
 103
 104   if (fgets(buf, MAXLINE, inf)) {
 105     str= malloc(sizeof(*line) + strlen(buf) + 1);
 106     if (!str) aargh("malloc");
 107     line= (logline*)str;
 108     line->next= NULL;
 109     line->start= str+sizeof(logline);
 110     strcpy(line->start, buf);
 111     line->name= line->rest= line->addr= NULL;
 112     /* look for unverifiable HELO information matching the regex
 113        H=[a-z0-9.- ]*[(][a-z0-9.-]*[)] [[][0-9.]*[]] */
 114     for (p= strchr(line->start, ' '); p; p= strchr(p+1, ' ')) {
 115       if (!strncmp(p, " H=", 3)) {
 116         r= strchr(p, '[');
 117         if (!r) break;
 118         q= strchr(p, ')');
 119         if (!q || q>r) break;
 120         p= strchr(p, '(');
 121         if (!p || p>q) break;
 122         line->name= p+1;
 123         line->rest= q;
 124         line->addr= r+1;
 125         break;
 126       }
 127     }
 128     if (line->name) {
 129       *line->rest= '\0';
 130       if (opts & OPT_DEBUG)
 131         msg("submitting %s", line->name);
 132       if (adns_submit(adns, line->name, adns_r_a,
 133                       adns_qf_quoteok_query|adns_qf_quoteok_cname|adns_qf_cname_loose,
 134                       NULL, &line->query))
 135         aargh("adns_submit");
 136       *line->rest= ')';
 137     } else {
 138       if (opts & OPT_DEBUG)
 139         msg("no query");
 140       line->query= NULL;
 141     }
 142     return line;
 143   }
 144   if (!feof(inf))
 145     aargh("fgets");
 146   return NULL;
 147 }
 148
 149 static void proclog(FILE *inf, FILE *outf, int maxpending, int opts) {
 150   int eof, err, len;
 151   adns_state adns;
 152   adns_answer *answer;
 153   logline *head, *tail, *line;
 154   adns_initflags initflags;
 155
 156   initflags= (opts & OPT_DEBUG) ? adns_if_debug : 0;
 157   if (config_text) {
 158     errno= adns_init_strcfg(&adns, initflags, stderr, config_text);
 159   } else {
 160     errno= adns_init(&adns, initflags, 0);
 161   }
 162   if (errno) aargh("adns_init");
 163   head= tail= readline(inf, adns, opts);
 164   len= 1; eof= 0;
 165   while (head) {
 166     while (head) {
 167       if (head->query) {
 168         if (opts & OPT_DEBUG)
 169           msg("%d in queue; checking %.*s", len,
 170               (int)(head->rest-head->name), guard_null(head->name));
 171         if (eof || len >= maxpending) {
 172           if (opts & OPT_POLL)
 173             err= adns_wait_poll(adns, &head->query, &answer, NULL);
 174           else
 175             err= adns_wait(adns, &head->query, &answer, NULL);
 176         } else {
 177           err= adns_check(adns, &head->query, &answer, NULL);
 178         }
 179         if (err == EAGAIN) break;
 180         if (err) {
 181           fprintf(stderr, "%s: adns_wait/check: %s", progname, strerror(err));
 182           exit(1);
 183         }
 184         if (answer->status == adns_s_ok) {
 185           const char *addr;
 186           int ok = 0;
 187           fprintf(outf, "%.*s", (int)(head->rest-head->start), head->start);
 188           while(answer->nrrs--) {
 189             addr= inet_ntoa(answer->rrs.inaddr[answer->nrrs]);
 190             ok |= !strncmp(addr, head->addr, strlen(addr));
 191             fprintf(outf, " [%s]", addr);
 192           }
 193           fprintf(outf, "%s%s", ok ? " OK" : "", head->rest);
 194         } else {
 195           if (opts & OPT_DEBUG)
 196             msg("query failed");
 197           fputs(head->start, outf);
 198         }
 199         free(answer);
 200         len--;
 201       } else {
 202         if (opts & OPT_DEBUG)
 203           msg("%d in queue; no query on this line", len);
 204         fputs(head->start, outf);
 205       }
 206       line= head; head= head->next;
 207       free(line);
 208     }
 209     if (!eof) {
 210       line= readline(inf, adns, opts);
 211       if (line) {
 212         if (!head) head= line;
 213         else tail->next= line;
 214         tail= line;
 215         if (line->query) len++;
 216       } else {
 217         eof= 1;
 218       }
 219     }
 220   }
 221   adns_finish(adns);
 222 }
 223
 224 static void printhelp(FILE *file) {
 225   fputs("usage: adnsheloex [<options>] [<logfile>]\n"
 226         "       adnsheloex --version|--help\n"
 227         "options: -c <concurrency>  set max number of outstanding queries\n"
 228         "         -p                use poll(2) instead of select(2)\n"
 229         "         -d                turn on debugging\n"
 230         "         -C <config>       use instead of contents of resolv.conf\n",
 231         stdout);
 232 }
 233
 234 static void usage(void) {
 235   printhelp(stderr);
 236   exit(1);
 237 }
 238
 239 int main(int argc, char *argv[]) {
 240   int c, opts, maxpending;
 241   extern char *optarg;
 242   FILE *inf;
 243
 244   if (argv[1] && !strncmp(argv[1],"--",2)) {
 245     if (!strcmp(argv[1],"--help")) {
 246       printhelp(stdout);
 247     } else if (!strcmp(argv[1],"--version")) {
 248       fputs(VERSION_MESSAGE("adnsheloex"),stdout);
 249     } else {
 250       usage();
 251     }
 252     if (ferror(stdout) || fclose(stdout)) { perror("stdout"); exit(1); }
 253     exit(0);
 254   }
 255
 256   maxpending= DEFMAXPENDING;
 257   opts= 0;
 258   while ((c= getopt(argc, argv, "c:C:dp")) != -1)
 259     switch (c) {
 260     case 'c':
 261       maxpending= atoi(optarg);
 262       if (maxpending < 1 || maxpending > MAXMAXPENDING) {
 263        fprintf(stderr, "%s: unfeasible concurrency %d\n", progname, maxpending);
 264        exit(1);
 265       }
 266       break;
 267     case 'C':
 268       config_text= optarg;
 269       break;
 270     case 'd':
 271       opts|= OPT_DEBUG;
 272       break;
 273     case 'p':
 274       opts|= OPT_POLL;
 275       break;
 276     default:
 277       usage();
 278     }
 279
 280   argc-= optind;
 281   argv+= optind;
 282
 283   inf= NULL;
 284   if (argc == 0)
 285     inf= stdin;
 286   else if (argc == 1)
 287     inf= fopen(*argv, "r");
 288   else
 289     usage();
 290
 291   if (!inf)
 292     aargh("couldn't open input");
 293
 294   proclog(inf, stdout, maxpending, opts);
 295
 296   if (fclose(inf))
 297     aargh("fclose input");
 298   if (fclose(stdout))
 299     aargh("fclose output");
 300
 301   return 0;
 302 }