Usermode/Applications/dnsresolve_src/main.c

   1 /*\r
   2  * DNS Resolver\r
   3  */\r
   4 #include <acess/sys.h>\r
   5 #include <stdio.h>\r
   6 #include <net.h>\r
   7 \r
   8 // === CONSTANTS ===\r
   9 #define NAMESERVER      {10,0,2,3}\r
  10 \r
  11 uint8_t packet[] = {\r
  12                 // --- UDP header\r
  13                 53, 0,  // Dest port\r
  14                 4, 0,   // IPv4\r
  15                 10,0,2,3,       // Dest address\r
  16                 // --- DNS Packet\r
  17                 0x13,0x37,\r
  18                 0x01,   // Recursion Desired\r
  19                 0x00,\r
  20                 0,1,    // QDCOUNT\r
  21                 0,0,\r
  22                 0,0,\r
  23                 0,0,    // ARCOUNT\r
  24                 \r
  25                 #if 0\r
  26                 // www.mutabah.net, A, IN\r
  27                 3,'w','w','w',\r
  28                 7,'m','u','t','a','b','a','h',\r
  29                 3,'n','e','t',\r
  30                 #else\r
  31                 // mussel.ucc.asn.au, A, IN\r
  32                 6,'m','u','s','s','e','l',\r
  33                 3,'u','c','c',\r
  34                 3,'a','s','n',\r
  35                 2,'a','u',\r
  36                 #endif\r
  37                 0,\r
  38                 0,1,    // A\r
  39                 0,1             // IN\r
  40         };\r
  41 \r
  42 // === TYPES ===\r
  43 typedef struct sDNSPacket\r
  44 {\r
  45         uint16_t        ID;\r
  46         // 1: Query/Response, 4: Opcode, 1: Authorative Answer, 1: Truncation, 1: Recursion Denied\r
  47         uint8_t opcode;\r
  48         uint8_t rcode;  // 1: Recusions Desired, 3: Zero, 4: Response Code\r
  49         uint16_t        qdcount;        // Question Count\r
  50         uint16_t        ancount;        // Answer Count\r
  51         uint16_t        nscount;        // Nameserver Resource Count\r
  52         uint16_t        arcount;        // Additional Records count\r
  53 }       tDNSPacket;\r
  54 \r
  55 // === PROTOTYPES ===\r
  56 \r
  57 // ==== CODE ====\r
  58 int main(int argc, char *argv[], char *envp[])\r
  59 {\r
  60          int    fd, tmp;\r
  61         uint16_t        port = 53;\r
  62         uint8_t         destip[4] = NAMESERVER;\r
  63         uint8_t         buf[512];\r
  64         tDNSPacket      *hdr = (void *) (buf + 4 + 4);\r
  65 \r
  66         fd = Net_OpenSocket(4, destip, "udp");\r
  67         if( fd == -1 ) {\r
  68                 fprintf(stderr, "Unable to create a UDP socket\n");\r
  69                 return 0;\r
  70         }\r
  71         port = 0;       ioctl(fd, ioctl(fd, 3, "getset_localport"), &port);\r
  72         port = 53;      ioctl(fd, ioctl(fd, 3, "getset_remoteport"), &port);\r
  73         ioctl(fd, ioctl(fd, 3, "set_remoteaddr"), &destip);\r
  74         tmp = 32;       ioctl(fd, ioctl(fd, 3, "getset_remotemask"), &tmp);\r
  75         \r
  76         write(fd, sizeof(packet), packet);\r
  77         read(fd, 512, buf);\r
  78         \r
  79         printf("hdr = {\n");\r
  80         printf("  .ID = 0x%04x\n", hdr->ID);\r
  81         printf("  .opcode = 0x%04x\n", hdr->opcode);\r
  82         printf("  .rcode = 0x%02x\n", hdr->rcode);\r
  83         printf("  .qdcount = 0x%04x\n", hdr->qdcount);\r
  84         printf("  .ancount = 0x%04x\n", hdr->ancount);\r
  85         printf("  .nscount = 0x%04x\n", hdr->nscount);\r
  86         printf("  .arcount = 0x%04x\n", hdr->arcount);\r
  87         printf("}\n");\r
  88         \r
  89         \r
  90         close(fd);\r
  91         return 0;\r
  92 }\r