update code

dns.c

@@ -518,6 +518,7 @@ int _dns_decode_head(struct dns_context *context)
     head->nscount = dns_read_short(&context->ptr);
     head->nrcount = dns_read_short(&context->ptr);
 
+	printf("qd = %d, an = %d\n", head->qdcount, head->ancount);
     return 0;
 }
 
@@ -544,53 +545,6 @@ int _dns_encode_head(struct dns_context *context)
     return len;
 }
 
-int dns_parse_domain(char *dns, int offset, char *domain, int *space)
-{
-	unsigned char val, *pval;
-	unsigned short len;
-
-	int sp = 0;
-	int domain_len = 0;
-	int org = 1;
-
-	while (1) {
-		pval = (unsigned char *)(dns + offset);
-		val = *pval;
-
-		if (val == 0) {
-			domain[domain_len - 1] = 0;
-			domain_len--;
-			if (org)
-				sp++;
-			break;
-		} else if (val <= 63) {
-			memcpy(domain + domain_len, dns + offset + 1, val);
-			domain_len += val;
-			domain[domain_len] = '.';
-			domain_len++;
-
-			offset += (val + 1);
-
-			if (org)
-				sp += (val + 1);
-		} else {
-			len = *(unsigned short *)(dns + offset);
-			len = ntohs(len);
-			len = len & (~0xc000);
-
-			if (org)
-				sp += 2;
-
-			org = 0;
-			offset = len;
-		}
-	}
-
-	*space = sp;
-
-	return 0;
-}
-
 int _dns_decode_domain(struct dns_context *context, char *output, int size)
 {
     int output_len = 0;
@@ -599,13 +553,6 @@ int _dns_decode_domain(struct dns_context *context, char *output, int size)
     unsigned char *ptr = context->ptr;
     int is_compressed = 0;
 
-	
-	int sp = 0;
-	dns_parse_domain(context->data, context->ptr - context->data, output, &sp);
-	context->ptr += sp;
-	return 0;
-	
-
     while (1) {
         len = *ptr;
         if (len == 0) {
@@ -615,9 +562,15 @@ int _dns_decode_domain(struct dns_context *context, char *output, int size)
         }
 
         if (len >= 0xC0) {
-			ptr = context->data + (dns_read_short(&ptr) & 0x3FFF);
+            len = dns_read_short(&ptr) & 0x3FFF;
+            if (is_compressed == 0) {
+                context->ptr = ptr;
+            }
+            ptr = context->data + len;
+            if (context->maxsize - (ptr - context->data) < 1) {
+                return -1;
+            }
             is_compressed = 1;
-			context->ptr += 2;
             continue;
         }
 
@@ -645,8 +598,6 @@ int _dns_decode_domain(struct dns_context *context, char *output, int size)
         context->ptr = ptr;
     }
 
-	printf("--%p\n", context->ptr);
-
     return 0;
 }