Config parsing: Provide a way to ignore unknown resolv.conf contents

[adns] / src / setup.c

diff --git a/src/setup.c b/src/setup.c
index 6060a08..c5ffed6 100644 (file)
--- a/src/setup.c
+++ b/src/setup.c
@@ -6,6 +6,7 @@
 /*
  *  This file is part of adns, which is
  *    Copyright (C) 1997-2000,2003,2006,2014  Ian Jackson
+ *    Copyright (C) 2014  Mark Wooding
  *    Copyright (C) 1999-2000,2003,2006  Tony Finch
  *    Copyright (C) 1991 Massachusetts Institute of Technology
  *  (See the file INSTALL for full details.)
@@ -259,21 +260,25 @@ static void ccf_sortlist(adns_state ads, const char *fn,
 
 static void ccf_options(adns_state ads, const char *fn,
                        int lno, const char *buf) {
-  const char *word;
+  const char *word, *rhs;
   char *ep;
   unsigned long v;
   int i,l;
 
   if (!buf) return;
 
+#define OPTION__IS(s,op) (l op (sizeof(s)-1) && !memcmp(word,s,(sizeof(s)-1)))
+#define OPTION_IS(s)     (OPTION__IS(s,==))
+#define OPTION_STARTS(s) (OPTION__IS(s,>=) ? ((rhs=word+sizeof(s)-1)) : 0)
+
   while (nextword(&buf,&word,&l)) {
-    if (l==5 && !memcmp(word,"debug",5)) {
+    if (OPTION_IS("debug")) {
       ads->iflags |= adns_if_debug;
       continue;
     }
-    if (l>=6 && !memcmp(word,"ndots:",6)) {
-      v= strtoul(word+6,&ep,10);
-      if (l==6 || ep != word+l || v > INT_MAX) {
+    if (OPTION_STARTS("ndots:")) {
+      v= strtoul(rhs,&ep,10);
+      if (ep==rhs || ep != word+l || v > INT_MAX) {
        configparseerr(ads,fn,lno,"option `%.*s' malformed"
                       " or has bad value",l,word);
        continue;
@@ -281,23 +286,23 @@ static void ccf_options(adns_state ads, const char *fn,
       ads->searchndots= v;
       continue;
     }
-    if (l>=12 && !memcmp(word,"adns_checkc:",12)) {
-      if (!strcmp(word+12,"none")) {
+    if (OPTION_STARTS("adns_checkc:")) {
+      if (!strcmp(rhs,"none")) {
        ads->iflags &= ~adns_if_checkc_freq;
        ads->iflags |= adns_if_checkc_entex;
-      } else if (!strcmp(word+12,"entex")) {
+      } else if (!strcmp(rhs,"entex")) {
        ads->iflags &= ~adns_if_checkc_freq;
        ads->iflags |= adns_if_checkc_entex;
-      } else if (!strcmp(word+12,"freq")) {
+      } else if (!strcmp(rhs,"freq")) {
        ads->iflags |= adns_if_checkc_freq;
       } else {
        configparseerr(ads,fn,lno, "option adns_checkc has bad value `%s' "
-                      "(must be none, entex or freq", word+12);
+                      "(must be none, entex or freq", rhs);
       }
       continue;
     }
-    if (l>=8 && !memcmp(word,"adns_af:",8)) {
-      word += 8;
+    if (OPTION_STARTS("adns_af:")) {
+      word= rhs;
       ads->iflags &= ~adns_if_afmask;
       if (strcmp(word,"any")) for (;;) {
        i= strcspn(word,",");
@@ -316,8 +321,29 @@ static void ccf_options(adns_state ads, const char *fn,
       }
       continue;
     }
-    adns__diag(ads,-1,0,"%s:%d: unknown option `%.*s'", fn,lno, l,word);
+    if (OPTION_IS("adns_ignoreunkcfg")) {
+      ads->config_report_unknown=0;
+      continue;
+    }
+    if (/* adns's query strategy is not configurable */
+       OPTION_STARTS("timeout:") ||
+       OPTION_STARTS("attempts:") ||
+       OPTION_IS("rotate") ||
+       /* adns provides the application with knob for this */
+       OPTION_IS("no-check-names") ||
+       /* adns normally does IPv6 if the application wants it; control
+        * this with the adns_af: option if you like */
+       OPTION_IS("inet6") ||
+       /* adns does not do edns0 and this is not a problem */
+       OPTION_IS("edns0"))
+      continue;
+    if (ads->config_report_unknown)
+      adns__diag(ads,-1,0,"%s:%d: unknown option `%.*s'", fn,lno, l,word);
   }
+
+#undef OPTION__IS
+#undef OPTION_IS
+#undef OPTION_STARTS
 }
 
 static void ccf_clearnss(adns_state ads, const char *fn,
@@ -354,8 +380,9 @@ static void ccf_lookup(adns_state ads, const char *fn, int lno,
       adns__diag(ads,-1,0,"%s:%d: yp lookups not supported by adns", fn,lno);
       found_bind=-1;
     } else {
-      adns__diag(ads,-1,0,"%s:%d: unknown `lookup' database `%.*s'",
-                fn,lno, l,word);
+      if (ads->config_report_unknown)
+       adns__diag(ads,-1,0,"%s:%d: unknown `lookup' database `%.*s'",
+                  fn,lno, l,word);
       found_bind=-1;
     }
   }
@@ -363,6 +390,10 @@ static void ccf_lookup(adns_state ads, const char *fn, int lno,
     adns__diag(ads,-1,0,"%s:%d: `lookup' specified, but not `bind'", fn,lno);
 }
 
+static void ccf_ignore(adns_state ads, const char *fn, int lno,
+                      const char *buf) {
+}
+
 static const struct configcommandinfo {
   const char *name;
   void (*fn)(adns_state ads, const char *fn, int lno, const char *buf);
@@ -375,6 +406,7 @@ static const struct configcommandinfo {
   { "clearnameservers",  ccf_clearnss    },
   { "include",           ccf_include     },
   { "lookup",            ccf_lookup      }, /* OpenBSD */
+  { "lwserver",          ccf_ignore      }, /* BIND9 lwresd */
   {  0                                   }
 };
 
@@ -480,8 +512,9 @@ static void readconfiggeneric(adns_state ads, const char *filename,
           !(strlen(ccip->name)==dirl && !memcmp(ccip->name,p,q-p));
         ccip++);
     if (!ccip->name) {
-      adns__diag(ads,-1,0,"%s:%d: unknown configuration directive `%.*s'",
-                filename,lno,(int)(q-p),p);
+      if (ads->config_report_unknown)
+       adns__diag(ads,-1,0,"%s:%d: unknown configuration directive `%.*s'",
+                  filename,lno,(int)(q-p),p);
       continue;
     }
     while (ctype_whitespace(*q)) q++;
@@ -566,6 +599,10 @@ static int init_begin(adns_state *ads_r, adns_initflags flags,
   adns_state ads;
   pid_t pid;
   
+  if (flags & ~(adns_initflags)(0x4fff))
+    /* 0x4000 is reserved for `harmless' future expansion */
+    return ENOSYS;
+
   ads= malloc(sizeof(*ads)); if (!ads) return errno;
 
   ads->iflags= flags;
@@ -589,6 +626,7 @@ static int init_begin(adns_state *ads_r, adns_initflags flags,
   ads->tcpstate= server_disconnected;
   timerclear(&ads->tcptimeout);
   ads->searchlist= 0;
+  ads->config_report_unknown=1;
 
   pid= getpid();
   ads->rand48xsubi[0]= pid;