Diff: DnsQuery.cpp

Revision:

13:9c6e83b0ae7c

Parent:

12:e23ef3dab4b9

Child:

14:248f32a9c48d

--- a/DnsQuery.cpp	Mon Feb 29 15:19:32 2016 +0000
+++ b/DnsQuery.cpp	Mon Feb 29 15:20:55 2016 +0000
@@ -48,20 +48,20 @@
 }
 
 
-static bool parseRR(uint8_t *resp, int& c, char* adr )
+static bool parseRR(uint8_t *resp, int &c, char *adr)
 {
     int n = 0;
-    while( (n=resp[c++]) != 0) {
+    while((n=resp[c++]) != 0) {
         if ((n & 0xc0) != 0) {
             //  This is a link
             c++;
             break;
         } else {
             //  skip this segment, not interested in string domain names
-            c+= n;  
+            c+= n;
         }
     }
-    
+
     int TYPE = (((int)resp[c])<<8) + resp[c+1];
     int CLASS = (((int)resp[c+2])<<8) + resp[c+3];
     int RDLENGTH = (((int)resp[c+8])<<8) + resp[c+9];
@@ -71,27 +71,26 @@
         sprintf(adr,"%d.%d.%d.%d", resp[c], resp[c+1], resp[c+2], resp[c+3]);
         c+= RDLENGTH;
         return true;
-    } else {
     }
     c+= RDLENGTH;
-    
+
     return false;
 }
 
 
-static bool resolve(unsigned char* resp, char* ipaddress)
+static bool resolve(unsigned char *resp, char *ipaddress)
 {
-    
+
     int ID = (((int)resp[0]) <<8) + resp[1];
     int QR = resp[2] >>7;
     int Opcode = (resp[2]>>3) & 0x0F;
     int RCODE = (resp[3] & 0x0F);
     int ANCOUNT = (((int)resp[6])<<8)+ resp[7];
-    
+
     if ((ID != 1) || (QR != 1) || (Opcode != 0) || (RCODE != 0)) {
         return false;
     }
-    
+
     int c = 12;
     int d;
     //  Skip domain question
@@ -99,14 +98,14 @@
         c+=d;
     }
     c+= 4; //   skip QTYPE and QCLASS
-    
+
     //  Here comes the resource record
     for (int ans = 0 ; ans < ANCOUNT; ans++) {
         if (parseRR(resp, c, ipaddress)) {
             return true;
         }
     }
-    
+
     return false;
 }
 
@@ -143,17 +142,20 @@
 int32_t dnsQuery(UDPSocket *socket, const char *hostname, char *ipaddress)
 {
     int len = 0;
-    if (hostname == NULL)
+    if (hostname == NULL) {
         return false;
+    }
     len = strlen(hostname);
-    if ((len >128) || (len == 0))
+    if ((len > 128) || (len == 0)) {
         return false;
-    
+    }
+
     int packetlen = /* size of HEADER structure */ 12 + /* size of QUESTION Structure */5 + len + 1;
     uint8_t *packet = new uint8_t[packetlen]; /* this is the UDP packet to send to the DNS */
-    if (packet == NULL)
+    if (packet == NULL) {
         return false;
-    
+    }
+
     //  Fill the header
     memset(packet, 0, packetlen);
     packet[1] = 1;      //  ID = 1
@@ -174,40 +176,41 @@
             packet[cnt] = 0;
         }
     }
-    
+
     //  Terminate this domain name with a zero entry
     packet[c++] = 0;
-    
+
     //  Set QTYPE
     packet[c++] = 0;
     packet[c++] = 1;
     //  Set QCLASS
     packet[c++] = 0;
     packet[c++] = 1;
-   
+
 
     if (socket->send(packet, packetlen) < 0) {
         delete packet;
         return false;
     }
     delete packet;
-    
+
     packet = new uint8_t [1024];
-    
+
     //  Receive the answer from DNS
     int response_length = 0;
     response_length = socket->recv(packet, 1024);
-    
+
     if (response_length > 0 ) {
         if (!resolve(packet, ipaddress)) {
             delete packet;
             return NS_ERROR_DNS_FAILURE;
         }
-                        
+
         //  cleanup and return
         delete packet;
         return 0;
     }
+    
     delete packet;
     return NS_ERROR_DNS_FAILURE;
 }