From acff2ca6dccce9ed309fe1ca3df5d89791eedb74 Mon Sep 17 00:00:00 2001 From: brain Date: Wed, 2 Aug 2006 20:44:46 +0000 Subject: More tidying git-svn-id: http://svn.inspircd.org/repository/trunk/inspircd@4655 e03df62e-2008-0410-955e-edbf42e46eb7 --- src/dns.cpp | 93 +++++++++++++++++++++++++++++++------------------------------ 1 file changed, 47 insertions(+), 46 deletions(-) (limited to 'src') diff --git a/src/dns.cpp b/src/dns.cpp index 60318dcc3..b82e705cd 100644 --- a/src/dns.cpp +++ b/src/dns.cpp @@ -135,14 +135,6 @@ class DNSRequest int SendRequests(const DNSHeader *header, const int length, QueryType qt); }; -/* - * Optimized by brain, these were using integer division and modulus. - * We can use logic shifts and logic AND to replace these even divisions - * and multiplications, it should be a bit faster (probably not noticably, - * but of course, more impressive). Also made these inline. - */ - - /* Fill a ResourceRecord class based on raw data input */ inline void DNS::FillResourceRecord(ResourceRecord* rr, const unsigned char *input) { @@ -244,25 +236,37 @@ int DNS::GetMasterSocket() /* Initialise the DNS UDP socket so that we can send requests */ DNS::DNS() { - log(DEBUG,"----- Initialize dns class ----- "); - memset(Classes,0,sizeof(Classes)); insp_inaddr addr; + + /* Clear the Resolver class table */ + memset(Classes,0,sizeof(Classes)); + + /* Seed random number generator, we use this to generate + * dns packet id's + */ srand((unsigned int)time(NULL)); + + /* Clear the namesever address */ memset(&myserver,0,sizeof(insp_inaddr)); + + /* Convert the nameserver address into an insp_inaddr */ if (insp_aton(Config->DNSServer,&addr) > 0) memcpy(&myserver,&addr,sizeof(insp_inaddr)); + /* Initialize mastersocket */ MasterSocket = socket(PF_PROTOCOL, SOCK_DGRAM, 0); if (MasterSocket != -1) { - log(DEBUG,"Set query socket nonblock"); + /* Did it succeed? */ if (fcntl(MasterSocket, F_SETFL, O_NONBLOCK) != 0) { + /* Couldn't make the socket nonblocking */ shutdown(MasterSocket,2); close(MasterSocket); MasterSocket = -1; } } + /* Have we got a socket and is it nonblocking? */ if (MasterSocket != -1) { #ifdef IPV6 @@ -278,10 +282,11 @@ DNS::DNS() addr.sin_port = 0; addr.sin_addr.s_addr = INADDR_ANY; #endif - log(DEBUG,"Binding query port"); + /* Bind the port */ if (bind(MasterSocket,(sockaddr *)&addr,sizeof(addr)) != 0) { - log(DEBUG,"Cant bind with source port = 0"); + /* Failed to bind */ + log(DEBUG,"Cant bind DNS::MasterSocket"); shutdown(MasterSocket,2); close(MasterSocket); MasterSocket = -1; @@ -289,63 +294,61 @@ DNS::DNS() if (MasterSocket >= 0) { - log(DEBUG,"Attach query port to socket engine"); + /* Hook the descriptor into the socket engine */ if (ServerInstance && ServerInstance->SE) ServerInstance->SE->AddFd(MasterSocket,true,X_ESTAB_DNS); } } } +/* Build a payload to be placed after the header, based upon input data, a resource type, a class and a pointer to a buffer */ int DNS::MakePayload(const char * const name, const unsigned short rr, const unsigned short rr_class, unsigned char * const payload) { - short payloadpos; - const char * tempchr, * tempchr2; - unsigned short l; - - payloadpos = 0; - tempchr2 = name; + short payloadpos = 0; + const char* tempchr, *tempchr2 = name; + unsigned short length; /* split name up into labels, create query */ while ((tempchr = strchr(tempchr2,'.')) != NULL) { - l = tempchr - tempchr2; - if (payloadpos + l + 1 > 507) + length = tempchr - tempchr2; + if (payloadpos + length + 1 > 507) return -1; - payload[payloadpos++] = l; - memcpy(&payload[payloadpos],tempchr2,l); - payloadpos += l; + payload[payloadpos++] = length; + memcpy(&payload[payloadpos],tempchr2,length); + payloadpos += length; tempchr2 = &tempchr[1]; } - l = strlen(tempchr2); - if (l) + length = strlen(tempchr2); + if (length) { - if (payloadpos + l + 2 > 507) + if (payloadpos + length + 2 > 507) return -1; - payload[payloadpos++] = l; - memcpy(&payload[payloadpos],tempchr2,l); - payloadpos += l; + payload[payloadpos++] = length; + memcpy(&payload[payloadpos],tempchr2,length); + payloadpos += length; payload[payloadpos++] = 0; } if (payloadpos > 508) return -1; - l = htons(rr); - memcpy(&payload[payloadpos],&l,2); - l = htons(rr_class); - memcpy(&payload[payloadpos + 2],&l,2); + length = htons(rr); + memcpy(&payload[payloadpos],&length,2); + length = htons(rr_class); + memcpy(&payload[payloadpos + 2],&length,2); return payloadpos + 4; } +/* Start lookup of an hostname to an IP address */ int DNS::GetIP(const char *name) { DNSHeader h; int id; int length; - DNSRequest* req; if ((length = this->MakePayload(name,DNS_QRY_A,1,(unsigned char*)&h.payload)) == -1) return -1; - req = this->AddQuery(&h, id); + DNSRequest* req = this->AddQuery(&h, id); if (req->SendRequests(&h,length,DNS_QRY_A) == -1) return -1; @@ -353,6 +356,7 @@ int DNS::GetIP(const char *name) return id; } +/* Start lookup of an IP address to a hostname */ int DNS::GetName(const insp_inaddr *ip) { #ifdef IPV6 @@ -362,7 +366,6 @@ int DNS::GetName(const insp_inaddr *ip) DNSHeader h; int id; int length; - DNSRequest* req; unsigned char* c = (unsigned char*)&ip->s_addr; @@ -371,7 +374,7 @@ int DNS::GetName(const insp_inaddr *ip) if ((length = this->MakePayload(query,DNS_QRY_PTR,1,(unsigned char*)&h.payload)) == -1) return -1; - req = this->AddQuery(&h, id); + DNSRequest* req = this->AddQuery(&h, id); if (req->SendRequests(&h,length,DNS_QRY_PTR) == -1) return -1; @@ -380,18 +383,16 @@ int DNS::GetName(const insp_inaddr *ip) #endif } -/* Return the next id which is ready, and the result attached to it - */ +/* Return the next id which is ready, and the result attached to it */ DNSResult DNS::GetResult() { /* Fetch dns query response and decide where it belongs */ DNSHeader header; DNSRequest *req; - int length; unsigned char buffer[sizeof(DNSHeader)]; /* Attempt to read a header */ - length = recv(MasterSocket,buffer,sizeof(DNSHeader),0); + int length = recv(MasterSocket,buffer,sizeof(DNSHeader),0); /* Did we get the whole header? */ if (length < 12) @@ -469,7 +470,7 @@ DNSInfo DNSRequest::ResultIsReady(DNSHeader &header, int length) int q = 0; int curanswer, o; ResourceRecord rr; - unsigned short p; + unsigned short ptr; if (!(header.flags1 & FLAGS_MASK_QR)) return std::make_pair((unsigned char*)NULL,"Not a query result"); @@ -561,8 +562,8 @@ DNSInfo DNSRequest::ResultIsReady(DNSHeader &header, int length) { if (header.payload[i] > 63) { - memcpy(&p,&header.payload[i],2); - i = ntohs(p) - 0xC000 - 12; + memcpy(&ptr,&header.payload[i],2); + i = ntohs(ptr) - 0xC000 - 12; } else { -- cgit v1.2.3