printrecord.c

   1 #include "uint16.h"
   2 #include "uint32.h"
   3 #include "error.h"
   4 #include "byte.h"
   5 #include "dns.h"
   6 #include "printrecord.h"
   7
   8 static char *d;
   9
  10 unsigned int printrecord_cat(stralloc *out,const char *buf,unsigned int len,unsigned int pos,const char *q,const char qtype[2])
  11 {
  12   const char *x;
  13   char misc[20];
  14   uint16 datalen;
  15   uint16 u16;
  16   uint32 u32;
  17   unsigned int newpos;
  18   int i;
  19   unsigned char ch;
  20
  21   pos = dns_packet_getname(buf,len,pos,&d); if (!pos) return 0;
  22   pos = dns_packet_copy(buf,len,pos,misc,10); if (!pos) return 0;
  23   uint16_unpack_big(misc + 8,&datalen);
  24   newpos = pos + datalen;
  25
  26   if (q) {
  27     if (!dns_domain_equal(d,q))
  28       return newpos;
  29     if (byte_diff(qtype,2,misc) && byte_diff(qtype,2,DNS_T_ANY))
  30       return newpos;
  31   }
  32
  33   if (!dns_domain_todot_cat(out,d)) return 0;
  34   if (!stralloc_cats(out," ")) return 0;
  35   uint32_unpack_big(misc + 4,&u32);
  36   if (!stralloc_catulong0(out,u32,0)) return 0;
  37
  38   if (byte_diff(misc + 2,2,DNS_C_IN)) {
  39     if (!stralloc_cats(out," weird class\n")) return 0;
  40     return newpos;
  41   }
  42
  43   x = 0;
  44   if (byte_equal(misc,2,DNS_T_NS)) x = " NS ";
  45   if (byte_equal(misc,2,DNS_T_PTR)) x = " PTR ";
  46   if (byte_equal(misc,2,DNS_T_CNAME)) x = " CNAME ";
  47   if (x) {
  48     pos = dns_packet_getname(buf,len,pos,&d); if (!pos) return 0;
  49     if (!stralloc_cats(out,x)) return 0;
  50     if (!dns_domain_todot_cat(out,d)) return 0;
  51   }
  52   else if (byte_equal(misc,2,DNS_T_MX)) {
  53     if (!stralloc_cats(out," MX ")) return 0;
  54     pos = dns_packet_copy(buf,len,pos,misc,2); if (!pos) return 0;
  55     pos = dns_packet_getname(buf,len,pos,&d); if (!pos) return 0;
  56     uint16_unpack_big(misc,&u16);
  57     if (!stralloc_catulong0(out,u16,0)) return 0;
  58     if (!stralloc_cats(out," ")) return 0;
  59     if (!dns_domain_todot_cat(out,d)) return 0;
  60   }
  61   else if (byte_equal(misc,2,DNS_T_SOA)) {
  62     if (!stralloc_cats(out," SOA ")) return 0;
  63     pos = dns_packet_getname(buf,len,pos,&d); if (!pos) return 0;
  64     if (!dns_domain_todot_cat(out,d)) return 0;
  65     if (!stralloc_cats(out," ")) return 0;
  66     pos = dns_packet_getname(buf,len,pos,&d); if (!pos) return 0;
  67     if (!dns_domain_todot_cat(out,d)) return 0;
  68     pos = dns_packet_copy(buf,len,pos,misc,20); if (!pos) return 0;
  69     for (i = 0;i < 5;++i) {
  70       if (!stralloc_cats(out," ")) return 0;
  71       uint32_unpack_big(misc + 4 * i,&u32);
  72       if (!stralloc_catulong0(out,u32,0)) return 0;
  73     }
  74   }
  75   else if (byte_equal(misc,2,DNS_T_A)) {
  76     if (datalen != 4) { errno = error_proto; return 0; }
  77     if (!stralloc_cats(out," A ")) return 0;
  78     pos = dns_packet_copy(buf,len,pos,misc,4); if (!pos) return 0;
  79     for (i = 0;i < 4;++i) {
  80       ch = misc[i];
  81       if (i) if (!stralloc_cats(out,".")) return 0;
  82       if (!stralloc_catulong0(out,ch,0)) return 0;
  83     }
  84   }
  85   else {
  86     if (!stralloc_cats(out," ")) return 0;
  87     uint16_unpack_big(misc,&u16);
  88     if (!stralloc_catulong0(out,u16,0)) return 0;
  89     if (!stralloc_cats(out," ")) return 0;
  90     while (datalen--) {
  91       pos = dns_packet_copy(buf,len,pos,misc,1); if (!pos) return 0;
  92       if ((misc[0] >= 33) && (misc[0] <= 126) && (misc[0] != '\\')) {
  93         if (!stralloc_catb(out,misc,1)) return 0;
  94       }
  95       else {
  96         ch = misc[0];
  97         misc[3] = '0' + (7 & ch); ch >>= 3;
  98         misc[2] = '0' + (7 & ch); ch >>= 3;
  99         misc[1] = '0' + (7 & ch);
 100         misc[0] = '\\';
 101         if (!stralloc_catb(out,misc,4)) return 0;
 102       }
 103     }
 104   }
 105
 106   if (!stralloc_cats(out,"\n")) return 0;
 107   if (pos != newpos) { errno = error_proto; return 0; }
 108   return newpos;
 109 }
 110
 111 unsigned int printrecord(stralloc *out,const char *buf,unsigned int len,unsigned int pos,const char *q,const char qtype[2])
 112 {
 113   if (!stralloc_copys(out,"")) return 0;
 114   return printrecord_cat(out,buf,len,pos,q,qtype);
 115 }