mdw@git.distorted.org.uk Git - adns/blob - src/setup.c

   1 /**/
   2
   3 #include "adns-internal.h"
   4
   5 void adns__vdiag(adns_state ads, adns_initflags prevent, const char *pfx,
   6                         int serv, const char *fmt, va_list al) {
   7   if (!(ads->iflags & adns_if_debug) && (!prevent || (ads->iflags & prevent))) return;
   8   if (serv>=0) {
   9     fprintf(stderr,"adns%s: nameserver %s: ",pfx,inet_ntoa(ads->servers[serv].addr));
  10   } else {
  11     fprintf(stderr,"adns%s: ",pfx);
  12   }
  13   vfprintf(stderr,fmt,al);
  14   fputc('\n',stderr);
  15 }
  16
  17 void adns__debug(adns_state ads, int serv, const char *fmt, ...) {
  18   va_list al;
  19
  20   va_start(al,fmt);
  21   vdiag(ads," debug",0,serv,fmt,al);
  22   va_end(al);
  23 }
  24
  25 void adns__swarn(adns_state ads, int serv, const char *fmt, ...) {
  26   va_list al;
  27
  28   va_start(al,fmt);
  29   vdiag(ads," warning",adns_if_noerrprint|adns_if_noserverwarn,serv,fmt,al);
  30   va_end(al);
  31 }
  32
  33 void adns__diag(adns_state ads, int serv, const char *fmt, ...) {
  34   va_list al;
  35
  36   va_start(al,fmt);
  37   vdiag(ads,"",adns_if_noerrprint,serv,fmt,al);
  38   va_end(al);
  39 }
  40
  41 static void addserver(adns_state ads, struct in_addr addr) {
  42   int i;
  43   struct server *ss;
  44
  45   for (i=0; i<ads->nservers; i++) {
  46     if (ads->servers[i].addr.s_addr == addr.s_addr) {
  47       debug(ads,"duplicate nameserver %s ignored",inet_ntoa(addr));
  48       return;
  49     }
  50   }
  51
  52   if (ads->nservers>=MAXSERVERS) {
  53     diag(ads,"too many nameservers, ignoring %s",inet_ntoa(addr));
  54     return;
  55   }
  56
  57   ss= ads->servers+ads->nservers;
  58   ss->addr= addr;
  59   ss->state= server_disc;
  60   ss->connw.head= ss->connw.tail= 0;
  61   ads->nservers++;
  62 }
  63
  64 static void configparseerr(adns_state ads, const char *fn, int lno,
  65                            const char *fmt, ...) {
  66   va_list al;
  67
  68   if (ads->iflags & adns_if_noerrprint) return;
  69   if (lno==-1) fprintf(stderr,"adns: %s: ",fn);
  70   else fprintf(stderr,"adns: %s:%d: ",fn,lno);
  71   va_start(al,fmt);
  72   vfprintf(stderr,fmt,al);
  73   va_end(al);
  74   fputc('\n',stderr);
  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   debug(ads,"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   diag(ads,"warning - `search' ignored FIXME");
  91 }
  92
  93 static void ccf_sortlist(adns_state ads, const char *fn, int lno, const char *buf) {
  94   diag(ads,"warning - `sortlist' ignored FIXME");
  95 }
  96
  97 static void ccf_options(adns_state ads, const char *fn, int lno, const char *buf) {
  98   if (!buf) return;
  99   diag(ads,"warning - `options' ignored FIXME");
 100 }
 101
 102 static void ccf_clearnss(adns_state ads, const char *fn, int lno, const char *buf) {
 103   ads->nservers= 0;
 104 }
 105
 106 static const struct configcommandinfo {
 107   const char *name;
 108   void (*fn)(adns_state ads, const char *fn, int lno, const char *buf);
 109 } configcommandinfos[]= {
 110   { "nameserver",        ccf_nameserver  },
 111   { "domain",            ccf_search      },
 112   { "search",            ccf_search      },
 113   { "sortlist",          ccf_sortlist    },
 114   { "options",           ccf_options     },
 115   { "clearnameservers",  ccf_clearnss    },
 116   {  0                                   }
 117 };
 118
 119 static void readconfig(adns_state ads, const char *filename) {
 120   char linebuf[2000], *p, *q;
 121   FILE *file;
 122   int lno, l, c;
 123   const struct configcommandinfo *ccip;
 124
 125   file= fopen(filename,"r");
 126   if (!file) {
 127     if (errno == ENOENT) {
 128       debug(ads,"configuration file `%s' does not exist",filename);
 129       return;
 130     }
 131     diag(ads,"cannot open configuration file `%s': %s",filename,strerror(errno));
 132     return;
 133   }
 134
 135   for (lno=1; fgets(linebuf,sizeof(linebuf),file); lno++) {
 136     l= strlen(linebuf);
 137     if (!l) continue;
 138     if (linebuf[l-1] != '\n' && !feof(file)) {
 139       diag(ads,"%s:%d: line too long",filename,lno);
 140       while ((c= getc(file)) != EOF && c != '\n') { }
 141       if (c == EOF) break;
 142       continue;
 143     }
 144     while (l>0 && ctype_whitespace(linebuf[l-1])) l--;
 145     linebuf[l]= 0;
 146     p= linebuf;
 147     while (ctype_whitespace(*p)) p++;
 148     if (*p == '#' || *p == '\n') continue;
 149     q= p;
 150     while (*q && !ctype_whitespace(*q)) q++;
 151     for (ccip=configcommandinfos;
 152          ccip->name && strncmp(ccip->name,p,q-p);
 153          ccip++);
 154     if (!ccip->name) {
 155       diag(ads,"%s:%d: unknown configuration directive `%.*s'",filename,lno,q-p,p);
 156       continue;
 157     }
 158     while (ctype_whitespace(*q)) q++;
 159     ccip->fn(ads,filename,lno,q);
 160   }
 161   if (ferror(file)) {
 162     diag(ads,"%s:%d: read error: %s",filename,lno,strerror(errno));
 163   }
 164   fclose(file);
 165 }
 166
 167 static const char *instrum_getenv(adns_state ads, const char *envvar) {
 168   const char *value;
 169
 170   value= getenv(envvar);
 171   if (!value) debug(ads,"environment variable %s not set",envvar);
 172   else debug(ads,"environment variable %s set to `%s'",envvar,value);
 173   return value;
 174 }
 175
 176 static void readconfigenv(adns_state ads, const char *envvar) {
 177   const char *filename;
 178
 179   if (ads->iflags & adns_if_noenv) {
 180     debug(ads,"not checking environment variable `%s'",envvar);
 181     return;
 182   }
 183   filename= instrum_getenv(ads,envvar);
 184   if (filename) readconfig(ads,filename);
 185 }
 186
 187 int adns_init(adns_state *ads_r, adns_initflags flags) {
 188   adns_state ads;
 189   const char *res_options, *adns_res_options;
 190   struct protoent *proto;
 191   int r;
 192
 193   ads= malloc(sizeof(*ads)); if (!ads) return errno;
 194   ads->tosend.head= ads->tosend.tail= 0;
 195   ads->timew.head= ads->timew.tail= 0;
 196   ads->childw.head= ads->childw.tail= 0;
 197   ads->output.head= ads->output.tail= 0;
 198   ads->nextid= 0x311f;
 199   ads->udpsocket= -1;
 200   ads->qbufavail= 0;
 201   ads->qbuf= 0;
 202   ads->tcpbufavail= ads->tcpbufused= ads->tcpbufdone= 0;
 203   ads->tcpbuf= 0;
 204   ads->iflags= flags;
 205   ads->nservers= 0;
 206   ads->iflags= flags;
 207
 208   res_options= instrum_getenv(ads,"RES_OPTIONS");
 209   adns_res_options= instrum_getenv(ads,"ADNS_RES_OPTIONS");
 210   ccf_options(ads,"RES_OPTIONS",-1,res_options);
 211   ccf_options(ads,"ADNS_RES_OPTIONS",-1,adns_res_options);
 212
 213   readconfig(ads,"/etc/resolv.conf");
 214   readconfigenv(ads,"RES_CONF");
 215   readconfigenv(ads,"ADNS_RES_CONF");
 216
 217   ccf_options(ads,"RES_OPTIONS",-1,res_options);
 218   ccf_options(ads,"ADNS_RES_OPTIONS",-1,adns_res_options);
 219
 220   ccf_search(ads,"LOCALDOMAIN",-1,instrum_getenv(ads,"LOCALDOMAIN"));
 221   ccf_search(ads,"ADNS_LOCALDOMAIN",-1,instrum_getenv(ads,"ADNS_LOCALDOMAIN"));
 222
 223   if (!ads->nservers) {
 224     struct in_addr ia;
 225     if (ads->iflags & adns_if_debug)
 226       fprintf(stderr,"adns: no nameservers, using localhost\n");
 227     ia.s_addr= INADDR_LOOPBACK;
 228     addserver(ads,ia);
 229   }
 230
 231   proto= getprotobyname("udp"); if (!proto) { r= ENOPROTOOPT; goto x_free; }
 232   ads->udpsocket= socket(AF_INET,SOCK_DGRAM,proto->p_proto);
 233   if (ads->udpsocket<0) { r= errno; goto x_free; }
 234
 235   *ads_r= ads;
 236   return 0;
 237
 238  x_free:
 239   free(ads);
 240   return r;
 241 }
 242
 243 int adns_finish(adns_state ads) {
 244   abort(); /* FIXME */
 245 }