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Diffstat (limited to 'src/dns.cpp')
-rw-r--r--src/dns.cpp123
1 files changed, 61 insertions, 62 deletions
diff --git a/src/dns.cpp b/src/dns.cpp
index b2c32c0fb..1adf5f8a2 100644
--- a/src/dns.cpp
+++ b/src/dns.cpp
@@ -121,7 +121,7 @@ class dns_connection
}
unsigned char* result_ready(dns_header &h, int length);
- int send_requests(const dns_header *h, const int l, QueryType qt);
+ int send_requests(const dns_header *header, const int length, QueryType qt);
};
/*
@@ -170,7 +170,7 @@ inline void dns_empty_header(unsigned char *output, const dns_header *header, co
}
-int dns_connection::send_requests(const dns_header *h, const int length, QueryType qt)
+int dns_connection::send_requests(const dns_header *header, const int length, QueryType qt)
{
insp_sockaddr addr;
unsigned char payload[sizeof(dns_header)];
@@ -178,7 +178,7 @@ int dns_connection::send_requests(const dns_header *h, const int length, QueryTy
this->rr_class = 1;
this->type = qt;
- dns_empty_header(payload,h,length);
+ dns_empty_header(payload,header,length);
memset(&addr,0,sizeof(addr));
#ifdef IPV6
@@ -199,24 +199,26 @@ int dns_connection::send_requests(const dns_header *h, const int length, QueryTy
return 0;
}
-dns_connection* dns_add_query(dns_header *h, int &id)
+dns_connection* dns_add_query(dns_header *header, int &id)
{
id = rand() % 65536;
- dns_connection * s = new dns_connection();
+ dns_connection* req = new dns_connection();
- h->id[0] = s->id[0] = id >> 8;
- h->id[1] = s->id[1] = id & 0xFF;
- h->flags1 = FLAGS_MASK_RD;
- h->flags2 = 0;
- h->qdcount = 1;
- h->ancount = 0;
- h->nscount = 0;
- h->arcount = 0;
+ header->id[0] = req->id[0] = id >> 8;
+ header->id[1] = req->id[1] = id & 0xFF;
+ header->flags1 = FLAGS_MASK_RD;
+ header->flags2 = 0;
+ header->qdcount = 1;
+ header->ancount = 0;
+ header->nscount = 0;
+ header->arcount = 0;
if (connections.find(id) == connections.end())
- connections[id] = s;
- return s;
+ connections[id] = req;
+
+ /* According to the C++ spec, new never returns NULL. */
+ return req;
}
void create_socket()
@@ -321,8 +323,7 @@ int DNS::dns_getip4(const char *name)
if ((length = dns_build_query_payload(name,DNS_QRY_A,1,(unsigned char*)&h.payload)) == -1)
return -1;
- if ((req = dns_add_query(&h, id)) == NULL)
- return -1;
+ req = dns_add_query(&h, id);
if (req->send_requests(&h,length,DNS_QRY_A) == -1)
return -1;
@@ -348,8 +349,7 @@ int DNS::dns_getname4(const insp_inaddr *ip)
if ((length = dns_build_query_payload(query,DNS_QRY_PTR,1,(unsigned char*)&h.payload)) == -1)
return -1;
- if ((req = dns_add_query(&h, id)) == NULL)
- return -1;
+ req = dns_add_query(&h, id);
if (req->send_requests(&h,length,DNS_QRY_PTR) == -1)
return -1;
@@ -363,8 +363,8 @@ int DNS::dns_getname4(const insp_inaddr *ip)
DNSResult DNS::dns_getresult()
{
/* retrieve result of DNS query (buffered) */
- dns_header h;
- dns_connection *c;
+ dns_header header;
+ dns_connection *req;
int length;
unsigned char buffer[sizeof(dns_header)];
@@ -373,10 +373,10 @@ DNSResult DNS::dns_getresult()
if (length < 12)
return std::make_pair(-1,"");
- dns_fill_header(&h,buffer,length - 12);
+ dns_fill_header(&header,buffer,length - 12);
// Get the id of this request
- unsigned long this_id = h.id[1] + (h.id[0] << 8);
+ unsigned long this_id = header.id[1] + (header.id[0] << 8);
// Do we have a pending request for it?
@@ -388,110 +388,110 @@ DNSResult DNS::dns_getresult()
}
else
{
- /* Remove the query from the list */
- c = (dns_connection*)n_iter->second;
- /* We don't delete c here, because its done later when needed */
- connections.erase(n_iter);
+ /* Remove the query from the list */
+ req = (dns_connection*)n_iter->second;
+ /* We don't delete c here, because its done later when needed */
+ connections.erase(n_iter);
}
- unsigned char* a = c->result_ready(h, length);
+ unsigned char* data = req->result_ready(header, length);
std::string resultstr;
- if (a == NULL)
+ if (data == NULL)
{
resultstr = "";
}
else
{
- if (c->type == DNS_QRY_A)
+ if (req->type == DNS_QRY_A)
{
- char formatted[1024];
- snprintf(formatted,1024,"%u.%u.%u.%u",a[0],a[1],a[2],a[3]);
- resultstr = std::string(formatted);
+ char formatted[16];
+ snprintf(formatted,16,"%u.%u.%u.%u",data[0],data[1],data[2],data[3]);
+ resultstr = formatted;
}
else
{
- resultstr = std::string((const char*)a);
+ resultstr = std::string((const char*)data);
}
}
- delete c;
+ delete req;
return std::make_pair(this_id,resultstr);
}
/** A result is ready, process it
*/
-unsigned char* dns_connection::result_ready(dns_header &h, int length)
+unsigned char* dns_connection::result_ready(dns_header &header, int length)
{
- int i, q, curanswer, o;
+ int i = 0;
+ int q = 0;
+ int curanswer, o;
dns_rr_middle rr;
unsigned short p;
- if ((h.flags1 & FLAGS_MASK_QR) == 0)
+ if (!(header.flags1 & FLAGS_MASK_QR))
{
log(DEBUG,"DNS: didnt get a query result");
return NULL;
}
- if ((h.flags1 & FLAGS_MASK_OPCODE) != 0)
+ if (header.flags1 & FLAGS_MASK_OPCODE)
{
log(DEBUG,"DNS: got an OPCODE and didnt want one");
return NULL;
}
- if ((h.flags2 & FLAGS_MASK_RCODE) != 0)
+ if (header.flags2 & FLAGS_MASK_RCODE)
{
log(DEBUG,"DNS lookup failed due to SERVFAIL");
return NULL;
}
- if (h.ancount < 1)
+ if (header.ancount < 1)
{
log(DEBUG,"DNS: no answers!");
return NULL;
}
- i = 0;
- q = 0;
length -= 12;
- while ((unsigned)q < h.qdcount && i < length)
+ while ((unsigned int)q < header.qdcount && i < length)
{
- if (h.payload[i] > 63)
+ if (header.payload[i] > 63)
{
i += 6;
q++;
}
else
{
- if (h.payload[i] == 0)
+ if (header.payload[i] == 0)
{
q++;
i += 5;
}
- else i += h.payload[i] + 1;
+ else i += header.payload[i] + 1;
}
}
curanswer = 0;
- while ((unsigned)curanswer < h.ancount)
+ while ((unsigned)curanswer < header.ancount)
{
q = 0;
while (q == 0 && i < length)
{
- if (h.payload[i] > 63)
+ if (header.payload[i] > 63)
{
i += 2;
q = 1;
}
else
{
- if (h.payload[i] == 0)
+ if (header.payload[i] == 0)
{
i++;
q = 1;
}
- else i += h.payload[i] + 1; /* skip length and label */
+ else i += header.payload[i] + 1; /* skip length and label */
}
}
if (length - i < 10)
{
return NULL;
}
- dns_fill_rr(&rr,&h.payload[i]);
+ dns_fill_rr(&rr,&header.payload[i]);
i += 10;
if (rr.type != this->type)
{
@@ -507,7 +507,7 @@ unsigned char* dns_connection::result_ready(dns_header &h, int length)
}
break;
}
- if ((unsigned int)curanswer == h.ancount)
+ if ((unsigned int)curanswer == header.ancount)
return NULL;
if (i + rr.rdlength > (unsigned int)length)
return NULL;
@@ -522,15 +522,15 @@ unsigned char* dns_connection::result_ready(dns_header &h, int length)
q = 0;
while (q == 0 && i < length && o + 256 < 1023)
{
- if (h.payload[i] > 63)
+ if (header.payload[i] > 63)
{
log(DEBUG,"DNS: h.payload[i] > 63");
- memcpy(&p,&h.payload[i],2);
+ memcpy(&p,&header.payload[i],2);
i = ntohs(p) - 0xC000 - 12;
}
else
{
- if (h.payload[i] == 0)
+ if (header.payload[i] == 0)
{
q = 1;
}
@@ -539,9 +539,9 @@ unsigned char* dns_connection::result_ready(dns_header &h, int length)
res[o] = '\0';
if (o != 0)
res[o++] = '.';
- memcpy(&res[o],&h.payload[i + 1],h.payload[i]);
- o += h.payload[i];
- i += h.payload[i] + 1;
+ memcpy(&res[o],&header.payload[i + 1],header.payload[i]);
+ o += header.payload[i];
+ i += header.payload[i] + 1;
}
}
}
@@ -549,11 +549,11 @@ unsigned char* dns_connection::result_ready(dns_header &h, int length)
break;
case DNS_QRY_A:
log(DEBUG,"DNS: got a result of type DNS_QRY_A");
- memcpy(res,&h.payload[i],rr.rdlength);
+ memcpy(res,&header.payload[i],rr.rdlength);
res[rr.rdlength] = '\0';
break;
default:
- memcpy(res,&h.payload[i],rr.rdlength);
+ memcpy(res,&header.payload[i],rr.rdlength);
res[rr.rdlength] = '\0';
break;
}
@@ -562,7 +562,6 @@ unsigned char* dns_connection::result_ready(dns_header &h, int length)
DNS::DNS()
{
- log(DEBUG,"Create blank DNS");
}
DNS::~DNS()