diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/dns.cpp | 1544 |
1 files changed, 771 insertions, 773 deletions
diff --git a/src/dns.cpp b/src/dns.cpp index e4ce602d6..b294c71bf 100644 --- a/src/dns.cpp +++ b/src/dns.cpp @@ -3,13 +3,13 @@ * +------------------------------------+ * * InspIRCd is copyright (C) 2002-2006 ChatSpike-Dev. - * E-mail: - * <brain@chatspike.net> - * <Craig@chatspike.net> + * E-mail: + * <brain@chatspike.net> + * <Craig@chatspike.net> * * Written by Craig Edwards, Craig McLure, and others. * This program is free but copyrighted software; see - * the file COPYING for details. + * the file COPYING for details. * * --------------------------------------------------- */ @@ -74,11 +74,7 @@ connlist connections; Resolver* dns_classes[MAX_DESCRIPTORS]; -#ifdef IPV6 -in6_addr servers4[8]; -#else -in_addr servers4[8]; -#endif +insp_inaddr servers[8]; int i4; int initdone = 0; int lastcreate = -1; @@ -86,44 +82,44 @@ int lastcreate = -1; class s_connection { public: - unsigned char id[2]; - unsigned int _class; - QueryType type; - int want_list; - int fd; + unsigned char id[2]; + unsigned int _class; + QueryType type; + int want_list; + int fd; }; class s_rr_middle { public: - QueryType type; - unsigned int _class; - unsigned long ttl; - unsigned int rdlength; + QueryType type; + unsigned int _class; + unsigned long ttl; + unsigned int rdlength; }; class s_header { public: - unsigned char id[2]; - unsigned int flags1; - unsigned int flags2; - unsigned int qdcount; - unsigned int ancount; - unsigned int nscount; - unsigned int arcount; - unsigned char payload[512]; + unsigned char id[2]; + unsigned int flags1; + unsigned int flags2; + unsigned int qdcount; + unsigned int ancount; + unsigned int nscount; + unsigned int arcount; + unsigned char payload[512]; }; void *dns_align(void *inp) { - char *p = (char*)inp; - int offby = ((char *)p - (char *)0) % (sizeof(void *) > sizeof(long) ? sizeof(void *) : sizeof(long)); - if (offby != 0) - return p + ((sizeof(void *) > sizeof(long) ? sizeof(void *) : sizeof(long)) - offby); - else - return p; + char *p = (char*)inp; + int offby = ((char *)p - (char *)0) % (sizeof(void *) > sizeof(long) ? sizeof(void *) : sizeof(long)); + if (offby != 0) + return p + ((sizeof(void *) > sizeof(long) ? sizeof(void *) : sizeof(long)) - offby); + else + return p; } /* @@ -135,574 +131,575 @@ void *dns_align(void *inp) inline void dns_fill_rr(s_rr_middle* rr, const unsigned char *input) { - rr->type = (QueryType)((input[0] << 8) + input[1]); - rr->_class = (input[2] << 8) + input[3]; - rr->ttl = (input[4] << 24) + (input[5] << 16) + (input[6] << 8) + input[7]; - rr->rdlength = (input[8] << 8) + input[9]; + rr->type = (QueryType)((input[0] << 8) + input[1]); + rr->_class = (input[2] << 8) + input[3]; + rr->ttl = (input[4] << 24) + (input[5] << 16) + (input[6] << 8) + input[7]; + rr->rdlength = (input[8] << 8) + input[9]; } inline void dns_fill_header(s_header *header, const unsigned char *input, const int l) { - header->id[0] = input[0]; - header->id[1] = input[1]; - header->flags1 = input[2]; - header->flags2 = input[3]; - header->qdcount = (input[4] << 8) + input[5]; - header->ancount = (input[6] << 8) + input[7]; - header->nscount = (input[8] << 8) + input[9]; - header->arcount = (input[10] << 8) + input[11]; - memcpy(header->payload,&input[12],l); + header->id[0] = input[0]; + header->id[1] = input[1]; + header->flags1 = input[2]; + header->flags2 = input[3]; + header->qdcount = (input[4] << 8) + input[5]; + header->ancount = (input[6] << 8) + input[7]; + header->nscount = (input[8] << 8) + input[9]; + header->arcount = (input[10] << 8) + input[11]; + memcpy(header->payload,&input[12],l); } inline void dns_empty_header(unsigned char *output, const s_header *header, const int l) { - output[0] = header->id[0]; - output[1] = header->id[1]; - output[2] = header->flags1; - output[3] = header->flags2; - output[4] = header->qdcount >> 8; - output[5] = header->qdcount & 0xFF; - output[6] = header->ancount >> 8; - output[7] = header->ancount & 0xFF; - output[8] = header->nscount >> 8; - output[9] = header->nscount & 0xFF; - output[10] = header->arcount >> 8; - output[11] = header->arcount & 0xFF; - memcpy(&output[12],header->payload,l); + output[0] = header->id[0]; + output[1] = header->id[1]; + output[2] = header->flags1; + output[3] = header->flags2; + output[4] = header->qdcount >> 8; + output[5] = header->qdcount & 0xFF; + output[6] = header->ancount >> 8; + output[7] = header->ancount & 0xFF; + output[8] = header->nscount >> 8; + output[9] = header->nscount & 0xFF; + output[10] = header->arcount >> 8; + output[11] = header->arcount & 0xFF; + memcpy(&output[12],header->payload,l); } void dns_close(int fd) { #ifndef THREADED_DNS - if (ServerInstance && ServerInstance->SE) - ServerInstance->SE->DelFd(fd); + if (ServerInstance && ServerInstance->SE) + ServerInstance->SE->DelFd(fd); #endif - log(DEBUG,"DNS: dns_close on fd %d",fd); - shutdown(fd,2); - close(fd); - return; + log(DEBUG,"DNS: dns_close on fd %d",fd); + shutdown(fd,2); + close(fd); + return; } void DNS::dns_init() { - FILE *f; - int i; - in_addr addr4; - char buf[1024]; - if (initdone == 1) - return; - i4 = 0; - - initdone = 1; - srand((unsigned int) TIME); - memset(servers4,'\0',sizeof(in_addr) * 8); - f = fopen("/etc/resolv.conf","r"); - if (f == NULL) - return; - while (fgets(buf,1024,f) != NULL) { - if (strncmp(buf,"nameserver",10) == 0) - { - i = 10; - while (buf[i] == ' ' || buf[i] == '\t') - i++; - if (i4 < 8) - { - if (dns_aton4_s(&buf[i],&addr4) != NULL) - memcpy(&servers4[i4++],&addr4,sizeof(in_addr)); - } - } - } - fclose(f); + FILE *f; + int i; + insp_inaddr addr; + char buf[1024]; + if (initdone == 1) + return; + i4 = 0; + + initdone = 1; + srand((unsigned int) TIME); + memset(servers,'\0',sizeof(insp_inaddr) * 8); + f = fopen("/etc/resolv.conf","r"); + if (f == NULL) + return; + while (fgets(buf,1024,f) != NULL) { + if (strncmp(buf,"nameserver",10) == 0) + { + i = 10; + while (buf[i] == ' ' || buf[i] == '\t') + i++; + if (i4 < 8) + { + if (insp_aton(&buf[i],&addr) == 0) + memcpy(&servers[i4++],&addr,sizeof(insp_inaddr)); + } + } + } + fclose(f); } void DNS::dns_init_2(const char* dnsserver) { - in_addr addr4; - i4 = 0; - srand((unsigned int) TIME); - memset(servers4,'\0',sizeof(in_addr) * 8); - if (dns_aton4_s(dnsserver,&addr4) != NULL) - memcpy(&servers4[i4++],&addr4,sizeof(in_addr)); + insp_inaddr addr; + i4 = 0; + srand((unsigned int) TIME); + memset(servers,'\0',sizeof(insp_inaddr) * 8); + if (insp_aton(dnsserver,&addr) == 0) + memcpy(&servers[i4++],&addr,sizeof(insp_inaddr)); } int dns_send_requests(const s_header *h, const s_connection *s, const int l) { - int i; - sockaddr_in addr4; - unsigned char payload[sizeof(s_header)]; + int i; + insp_sockaddr addr; + unsigned char payload[sizeof(s_header)]; - dns_empty_header(payload,h,l); + dns_empty_header(payload,h,l); - i = 0; + i = 0; - /* otherwise send via standard ipv4 boringness */ - memset(&addr4,0,sizeof(addr4)); - memcpy(&addr4.sin_addr,&servers4[i],sizeof(addr4.sin_addr)); - addr4.sin_family = AF_INET; - addr4.sin_port = htons(53); - if (sendto(s->fd, payload, l + 12, 0, (sockaddr *) &addr4, sizeof(addr4)) == -1) - { - return -1; - } + /* otherwise send via standard ipv4 boringness */ + memset(&addr,0,sizeof(addr)); +#ifdef IPV6 + memcpy(&addr.sin6_addr,&servers[i],sizeof(addr.sin6_addr)); + addr.sin6_family = AF_FAMILY; + addr.sin6_port = htons(53); +#else + memcpy(&addr.sin_addr.s_addr,&servers[i],sizeof(addr.sin_addr)); + addr.sin_family = AF_FAMILY; + addr.sin_port = htons(53); +#endif + if (sendto(s->fd, payload, l + 12, 0, (sockaddr *) &addr, sizeof(addr)) == -1) + { + log(DEBUG,"Error in sendto!"); + return -1; + } - return 0; + return 0; } s_connection *dns_add_query(s_header *h) { - s_connection * s = new s_connection; - int id = rand() % 65536; - - /* set header flags */ - h->id[0] = s->id[0] = id >> 8; /* verified by dns_getresult_s() */ - h->id[1] = s->id[1] = id & 0xFF; - h->flags1 = 0 | FLAGS1_MASK_RD; - h->flags2 = 0; - h->qdcount = 1; - h->ancount = 0; - h->nscount = 0; - h->arcount = 0; - s->want_list = 0; - s->fd = socket(PF_INET, SOCK_DGRAM, 0); - if (s->fd != -1) - { - if (fcntl(s->fd, F_SETFL, O_NONBLOCK) != 0) - { - shutdown(s->fd,2); - close(s->fd); - s->fd = -1; - } - } - if (s->fd != -1) - { - sockaddr_in addr; - memset(&addr,0,sizeof(addr)); - addr.sin_family = AF_INET; - addr.sin_port = 0; - addr.sin_addr.s_addr = INADDR_ANY; - if (bind(s->fd,(sockaddr *)&addr,sizeof(addr)) != 0) - { - shutdown(s->fd,2); - close(s->fd); - s->fd = -1; - } - } - if (s->fd == -1) - { - DELETE(s); - return NULL; - } - /* create new connection object, add to linked list */ + s_connection * s = new s_connection; + int id = rand() % 65536; + + /* set header flags */ + h->id[0] = s->id[0] = id >> 8; /* verified by dns_getresult_s() */ + h->id[1] = s->id[1] = id & 0xFF; + h->flags1 = 0 | FLAGS1_MASK_RD; + h->flags2 = 0; + h->qdcount = 1; + h->ancount = 0; + h->nscount = 0; + h->arcount = 0; + s->want_list = 0; + s->fd = socket(PF_PROTOCOL, SOCK_DGRAM, 0); + if (s->fd != -1) + { + log(DEBUG,"Set query socket nonblock"); + if (fcntl(s->fd, F_SETFL, O_NONBLOCK) != 0) + { + shutdown(s->fd,2); + close(s->fd); + s->fd = -1; + } + } + if (s->fd != -1) + { +#ifdef IPV6 + insp_sockaddr addr; + memset(&addr,0,sizeof(addr)); + addr.sin6_family = AF_FAMILY; + addr.sin6_port = 0; + memset(&addr.sin6_addr,255,sizeof(in6_addr)); +#else + insp_sockaddr addr; + memset(&addr,0,sizeof(addr)); + addr.sin_family = AF_FAMILY; + addr.sin_port = 0; + addr.sin_addr.s_addr = INADDR_ANY; + if (bind(s->fd,(sockaddr *)&addr,sizeof(addr)) != 0) + { + log(DEBUG,"Cant bind with source port = 0"); + shutdown(s->fd,2); + close(s->fd); + s->fd = -1; + } +#endif + } + if (s->fd == -1) + { + DELETE(s); + return NULL; + } + /* create new connection object, add to linked list */ #ifdef THREADED_DNS - pthread_mutex_lock(&connmap_lock); + pthread_mutex_lock(&connmap_lock); #endif - if (connections.find(s->fd) == connections.end()) - connections[s->fd] = s; + if (connections.find(s->fd) == connections.end()) + connections[s->fd] = s; #ifdef THREADED_DNS - pthread_mutex_unlock(&connmap_lock); + pthread_mutex_unlock(&connmap_lock); #endif - return s; + return s; } int dns_build_query_payload(const char * const name, const unsigned short rr, const unsigned short _class, unsigned char * const payload) { - short payloadpos; - const char * tempchr, * tempchr2; - unsigned short l; - - payloadpos = 0; - tempchr2 = name; - - /* split name up into labels, create query */ - while ((tempchr = strchr(tempchr2,'.')) != NULL) - { - l = tempchr - tempchr2; - if (payloadpos + l + 1 > 507) - return -1; - payload[payloadpos++] = l; - memcpy(&payload[payloadpos],tempchr2,l); - payloadpos += l; - tempchr2 = &tempchr[1]; - } - l = strlen(tempchr2); - if (l) - { - if (payloadpos + l + 2 > 507) - return -1; - payload[payloadpos++] = l; - memcpy(&payload[payloadpos],tempchr2,l); - payloadpos += l; - payload[payloadpos++] = '\0'; - } - if (payloadpos > 508) - return -1; - l = htons(rr); - memcpy(&payload[payloadpos],&l,2); - l = htons(_class); - memcpy(&payload[payloadpos + 2],&l,2); - return payloadpos + 4; -} - -in_addr* DNS::dns_aton4(const char * const ipstring) -{ - static in_addr ip; - return dns_aton4_s(ipstring,&ip); -} - -in_addr* DNS::dns_aton4_r(const char *ipstring) { /* ascii to numeric (reentrant): convert string to new 4part IP addr struct */ - in_addr* ip; - ip = new in_addr; - if(dns_aton4_s(ipstring,ip) == NULL) - { - DELETE(ip); - return NULL; - } - return ip; -} - -in_addr* DNS::dns_aton4_s(const char *ipstring, in_addr *ip) { /* ascii to numeric (buffered): convert string to given 4part IP addr struct */ - inet_aton(ipstring,ip); - return ip; + short payloadpos; + const char * tempchr, * tempchr2; + unsigned short l; + + payloadpos = 0; + tempchr2 = name; + + /* split name up into labels, create query */ + while ((tempchr = strchr(tempchr2,'.')) != NULL) + { + l = tempchr - tempchr2; + if (payloadpos + l + 1 > 507) + return -1; + payload[payloadpos++] = l; + memcpy(&payload[payloadpos],tempchr2,l); + payloadpos += l; + tempchr2 = &tempchr[1]; + } + l = strlen(tempchr2); + if (l) + { + if (payloadpos + l + 2 > 507) + return -1; + payload[payloadpos++] = l; + memcpy(&payload[payloadpos],tempchr2,l); + payloadpos += l; + payload[payloadpos++] = '\0'; + } + if (payloadpos > 508) + return -1; + l = htons(rr); + memcpy(&payload[payloadpos],&l,2); + l = htons(_class); + memcpy(&payload[payloadpos + 2],&l,2); + return payloadpos + 4; } int DNS::dns_getip4(const char *name) { /* build, add and send A query; retrieve result with dns_getresult() */ - s_header h; - s_connection *s; - int l; - - dns_init(); - - - l = dns_build_query_payload(name,DNS_QRY_A,1,(unsigned char *)&h.payload); - if (l == -1) - return -1; - s = dns_add_query(&h); - if (s == NULL) - return -1; - s->_class = 1; - s->type = DNS_QRY_A; - if (dns_send_requests(&h,s,l) == -1) - return -1; - - return s->fd; + s_header h; + s_connection *s; + int l; + + dns_init(); + + + l = dns_build_query_payload(name,DNS_QRY_A,1,(unsigned char *)&h.payload); + if (l == -1) + return -1; + s = dns_add_query(&h); + if (s == NULL) + return -1; + s->_class = 1; + s->type = DNS_QRY_A; + if (dns_send_requests(&h,s,l) == -1) + return -1; + + return s->fd; } int DNS::dns_getip4list(const char *name) { /* build, add and send A query; retrieve result with dns_getresult() */ - s_header h; - s_connection *s; - int l; - - dns_init(); - - l = dns_build_query_payload(name,DNS_QRY_A,1,(unsigned char *)&h.payload); - if (l == -1) - return -1; - s = dns_add_query(&h); - if (s == NULL) - return -1; - s->_class = 1; - s->type = DNS_QRY_A; - s->want_list = 1; - if (dns_send_requests(&h,s,l) == -1) - return -1; - - return s->fd; + s_header h; + s_connection *s; + int l; + + dns_init(); + + l = dns_build_query_payload(name,DNS_QRY_A,1,(unsigned char *)&h.payload); + if (l == -1) + return -1; + s = dns_add_query(&h); + if (s == NULL) + return -1; + s->_class = 1; + s->type = DNS_QRY_A; + s->want_list = 1; + if (dns_send_requests(&h,s,l) == -1) + return -1; + + return s->fd; } -int DNS::dns_getname4(const in_addr *ip) { /* build, add and send PTR query; retrieve result with dns_getresult() */ - char query[512]; - s_header h; - s_connection * s; - unsigned char *c; - int l; - - c = (unsigned char *)&ip->s_addr; - - sprintf(query,"%d.%d.%d.%d.in-addr.arpa",c[3],c[2],c[1],c[0]); - - l = dns_build_query_payload(query,DNS_QRY_PTR,1,(unsigned char *)&h.payload); - if (l == -1) - return -1; - s = dns_add_query(&h); - if (s == NULL) - return -1; - s->_class = 1; - s->type = DNS_QRY_PTR; - if (dns_send_requests(&h,s,l) == -1) - return -1; - - return s->fd; +int DNS::dns_getname4(const insp_inaddr *ip) +{ /* build, add and send PTR query; retrieve result with dns_getresult() */ +#ifdef IPV6 + return -1; +#else + log(DEBUG,"DNS::dns_getname4"); + char query[512]; + s_header h; + s_connection * s; + unsigned char *c; + int l; + + c = (unsigned char *)&ip->s_addr; + + sprintf(query,"%d.%d.%d.%d.in-addr.arpa",c[3],c[2],c[1],c[0]); + + l = dns_build_query_payload(query,DNS_QRY_PTR,1,(unsigned char *)&h.payload); + if (l == -1) + return -1; + s = dns_add_query(&h); + if (s == NULL) + return -1; + s->_class = 1; + s->type = DNS_QRY_PTR; + if (dns_send_requests(&h,s,l) == -1) + return -1; + + return s->fd; +#endif } char* DNS::dns_getresult(const int cfd) { /* retrieve result of DNS query */ - log(DEBUG,"DNS: dns_getresult with cfd=%d",cfd); - return dns_getresult_s(cfd,this->localbuf); + log(DEBUG,"DNS: dns_getresult with cfd=%d",cfd); + return dns_getresult_s(cfd,this->localbuf); } char* DNS::dns_getresult_s(const int cfd, char *res) { /* retrieve result of DNS query (buffered) */ - s_header h; - s_connection *c; - int l, i, q, curanswer, o; - s_rr_middle rr; - unsigned char buffer[sizeof(s_header)]; - unsigned short p; + s_header h; + s_connection *c; + int l, i, q, curanswer, o; + s_rr_middle rr; + unsigned char buffer[sizeof(s_header)]; + unsigned short p; - if (res) - *res = 0; + if (res) + *res = 0; - /* FireDNS used a linked list for this. How ugly (and slow). */ + /* FireDNS used a linked list for this. How ugly (and slow). */ #ifdef THREADED_DNS - /* XXX: STL really does NOT like being poked and prodded in more than - * one orifice by threaded apps. Make sure we remain nice to it, and - * lock a mutex around any access to the std::map. - */ - pthread_mutex_lock(&connmap_lock); + /* XXX: STL really does NOT like being poked and prodded in more than + * one orifice by threaded apps. Make sure we remain nice to it, and + * lock a mutex around any access to the std::map. + */ + pthread_mutex_lock(&connmap_lock); #endif - connlist_iter n_iter = connections.find(cfd); - if (n_iter == connections.end()) - { - log(DEBUG,"DNS: got a response for a query we didnt send with fd=%d",cfd); + connlist_iter n_iter = connections.find(cfd); + if (n_iter == connections.end()) + { + log(DEBUG,"DNS: got a response for a query we didnt send with fd=%d",cfd); #ifdef THREADED_DNS - pthread_mutex_unlock(&connmap_lock); + pthread_mutex_unlock(&connmap_lock); #endif - return NULL; - } - else - { - /* Remove the query from the list */ - c = (s_connection*)n_iter->second; - /* We don't delete c here, because its done later when needed */ - connections.erase(n_iter); - } + return NULL; + } + else + { + /* Remove the query from the list */ + c = (s_connection*)n_iter->second; + /* We don't delete c here, because its done later when needed */ + connections.erase(n_iter); + } #ifdef THREADED_DNS - pthread_mutex_unlock(&connmap_lock); + pthread_mutex_unlock(&connmap_lock); #endif - l = recv(c->fd,buffer,sizeof(s_header),0); - dns_close(c->fd); - if (l < 12) - { - DELETE(c); - return NULL; - } - dns_fill_header(&h,buffer,l - 12); - if (c->id[0] != h.id[0] || c->id[1] != h.id[1]) - { - log(DEBUG,"DNS: id mismatch on query"); - DELETE(c); - return NULL; /* ID mismatch */ - } - if ((h.flags1 & FLAGS1_MASK_QR) == 0) - { - log(DEBUG,"DNS: didnt get a query result"); - DELETE(c); - return NULL; - } - if ((h.flags1 & FLAGS1_MASK_OPCODE) != 0) - { - log(DEBUG,"DNS: got an OPCODE and didnt want one"); - DELETE(c); - return NULL; - } - if ((h.flags2 & FLAGS2_MASK_RCODE) != 0) - { - log(DEBUG,"DNS lookup failed due to SERVFAIL"); - DELETE(c); - return NULL; - } - if (h.ancount < 1) - { - log(DEBUG,"DNS: no answers!"); - DELETE(c); - return NULL; - } - i = 0; - q = 0; - l -= 12; - while ((unsigned)q < h.qdcount && i < l) - { - if (h.payload[i] > 63) - { - i += 6; - q++; - } - else - { - if (h.payload[i] == 0) - { - q++; - i += 5; - } - else i += h.payload[i] + 1; - } - } - curanswer = 0; - while ((unsigned)curanswer < h.ancount) - { - q = 0; - while (q == 0 && i < l) - { - if (h.payload[i] > 63) - { - i += 2; - q = 1; - } - else - { - if (h.payload[i] == 0) - { - i++; - q = 1; - } - else i += h.payload[i] + 1; /* skip length and label */ - } - } - if (l - i < 10) - { - DELETE(c); - return NULL; - } - dns_fill_rr(&rr,&h.payload[i]); - i += 10; - if (rr.type != c->type) - { - curanswer++; - i += rr.rdlength; - continue; - } - if (rr._class != c->_class) - { - curanswer++; - i += rr.rdlength; - continue; - } - break; - } - if ((unsigned)curanswer == h.ancount) - return NULL; - if ((unsigned)i + rr.rdlength > (unsigned)l) - return NULL; - if (rr.rdlength > 1023) - return NULL; - - switch (rr.type) - { - case DNS_QRY_PTR: - log(DEBUG,"DNS: got a result of type DNS_QRY_PTR"); - o = 0; - q = 0; - while (q == 0 && i < l && o + 256 < 1023) - { - if (h.payload[i] > 63) - { - log(DEBUG,"DNS: h.payload[i] > 63"); - memcpy(&p,&h.payload[i],2); - i = ntohs(p) - 0xC000 - 12; - } - else - { - if (h.payload[i] == 0) - { - q = 1; - } - else - { - 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; - } - } - } - res[o] = '\0'; - break; - case DNS_QRY_A: - log(DEBUG,"DNS: got a result of type DNS_QRY_A"); - if (c->want_list) - { - dns_ip4list *alist = (dns_ip4list *) res; /* we have to trust that this is aligned */ - while ((char *)alist - (char *)res < 700) - { - if (rr.type != DNS_QRY_A) - break; - if (rr._class != 1) - break; - if (rr.rdlength != 4) - { - DELETE(c); - return NULL; - } - memcpy(&alist->ip,&h.payload[i],4); - if ((unsigned)++curanswer >= h.ancount) - break; - i += rr.rdlength; - q = 0; - while (q == 0 && i < l) - { - if (h.payload[i] > 63) - { - i += 2; - q = 1; - } - else - { - if (h.payload[i] == 0) - { - i++; - q = 1; - } - else i += h.payload[i] + 1; - } - } - if (l - i < 10) - { - DELETE(c); - return NULL; - } - dns_fill_rr(&rr,&h.payload[i]); - i += 10; - alist->next = (dns_ip4list *) dns_align(((char *) alist) + sizeof(dns_ip4list)); - alist = alist->next; - alist->next = NULL; - } - alist->next = NULL; - break; - } - memcpy(res,&h.payload[i],rr.rdlength); - res[rr.rdlength] = '\0'; - break; - default: - memcpy(res,&h.payload[i],rr.rdlength); - res[rr.rdlength] = '\0'; - break; - } - DELETE(c); - return res; + l = recv(c->fd,buffer,sizeof(s_header),0); + dns_close(c->fd); + if (l < 12) + { + DELETE(c); + return NULL; + } + dns_fill_header(&h,buffer,l - 12); + if (c->id[0] != h.id[0] || c->id[1] != h.id[1]) + { + log(DEBUG,"DNS: id mismatch on query"); + DELETE(c); + return NULL; /* ID mismatch */ + } + if ((h.flags1 & FLAGS1_MASK_QR) == 0) + { + log(DEBUG,"DNS: didnt get a query result"); + DELETE(c); + return NULL; + } + if ((h.flags1 & FLAGS1_MASK_OPCODE) != 0) + { + log(DEBUG,"DNS: got an OPCODE and didnt want one"); + DELETE(c); + return NULL; + } + if ((h.flags2 & FLAGS2_MASK_RCODE) != 0) + { + log(DEBUG,"DNS lookup failed due to SERVFAIL"); + DELETE(c); + return NULL; + } + if (h.ancount < 1) + { + log(DEBUG,"DNS: no answers!"); + DELETE(c); + return NULL; + } + i = 0; + q = 0; + l -= 12; + while ((unsigned)q < h.qdcount && i < l) + { + if (h.payload[i] > 63) + { + i += 6; + q++; + } + else + { + if (h.payload[i] == 0) + { + q++; + i += 5; + } + else i += h.payload[i] + 1; + } + } + curanswer = 0; + while ((unsigned)curanswer < h.ancount) + { + q = 0; + while (q == 0 && i < l) + { + if (h.payload[i] > 63) + { + i += 2; + q = 1; + } + else + { + if (h.payload[i] == 0) + { + i++; + q = 1; + } + else i += h.payload[i] + 1; /* skip length and label */ + } + } + if (l - i < 10) + { + DELETE(c); + return NULL; + } + dns_fill_rr(&rr,&h.payload[i]); + i += 10; + if (rr.type != c->type) + { + curanswer++; + i += rr.rdlength; + continue; + } + if (rr._class != c->_class) + { + curanswer++; + i += rr.rdlength; + continue; + } + break; + } + if ((unsigned)curanswer == h.ancount) + return NULL; + if ((unsigned)i + rr.rdlength > (unsigned)l) + return NULL; + if (rr.rdlength > 1023) + return NULL; + + switch (rr.type) + { + case DNS_QRY_PTR: + log(DEBUG,"DNS: got a result of type DNS_QRY_PTR"); + o = 0; + q = 0; + while (q == 0 && i < l && o + 256 < 1023) + { + if (h.payload[i] > 63) + { + log(DEBUG,"DNS: h.payload[i] > 63"); + memcpy(&p,&h.payload[i],2); + i = ntohs(p) - 0xC000 - 12; + } + else + { + if (h.payload[i] == 0) + { + q = 1; + } + else + { + 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; + } + } + } + res[o] = '\0'; + break; + case DNS_QRY_A: + log(DEBUG,"DNS: got a result of type DNS_QRY_A"); + if (c->want_list) + { + dns_ip4list *alist = (dns_ip4list *) res; /* we have to trust that this is aligned */ + while ((char *)alist - (char *)res < 700) + { + if (rr.type != DNS_QRY_A) + break; + if (rr._class != 1) + break; + if (rr.rdlength != 4) + { + DELETE(c); + return NULL; + } + memcpy(&alist->ip,&h.payload[i],4); + if ((unsigned)++curanswer >= h.ancount) + break; + i += rr.rdlength; + q = 0; + while (q == 0 && i < l) + { + if (h.payload[i] > 63) + { + i += 2; + q = 1; + } + else + { + if (h.payload[i] == 0) + { + i++; + q = 1; + } + else i += h.payload[i] + 1; + } + } + if (l - i < 10) + { + DELETE(c); + return NULL; + } + dns_fill_rr(&rr,&h.payload[i]); + i += 10; + alist->next = (dns_ip4list *) dns_align(((char *) alist) + sizeof(dns_ip4list)); + alist = alist->next; + alist->next = NULL; + } + alist->next = NULL; + break; + } + memcpy(res,&h.payload[i],rr.rdlength); + res[rr.rdlength] = '\0'; + break; + default: + memcpy(res,&h.payload[i],rr.rdlength); + res[rr.rdlength] = '\0'; + break; + } + DELETE(c); + return res; } DNS::DNS() { - dns_init(); - log(DEBUG,"Create blank DNS"); + dns_init(); + log(DEBUG,"Create blank DNS"); } DNS::DNS(const std::string &dnsserver) { - dns_init_2(dnsserver.c_str()); - log(DEBUG,"Create DNS with server '%s'",dnsserver.c_str()); + dns_init_2(dnsserver.c_str()); + log(DEBUG,"Create DNS with server '%s'",dnsserver.c_str()); } void DNS::SetNS(const std::string &dnsserver) { - dns_init_2(dnsserver.c_str()); - log(DEBUG,"Set NS"); + dns_init_2(dnsserver.c_str()); + log(DEBUG,"Set NS"); } DNS::~DNS() @@ -711,69 +708,69 @@ DNS::~DNS() bool DNS::ReverseLookup(const std::string &ip, bool ins) { - if (ServerInstance && ServerInstance->stats) - ServerInstance->stats->statsDns++; - binip = dns_aton4(ip.c_str()); - if (binip == NULL) - { - return false; - } - - this->myfd = dns_getname4(binip); - if (this->myfd == -1) - { - return false; - } - log(DEBUG,"DNS: ReverseLookup, fd=%d",this->myfd); + if (ServerInstance && ServerInstance->stats) + ServerInstance->stats->statsDns++; + insp_inaddr binip; + if (insp_aton(ip.c_str(), &binip)) + { + return false; + } + + this->myfd = dns_getname4(&binip); + if (this->myfd == -1) + { + return false; + } + log(DEBUG,"DNS: ReverseLookup, fd=%d",this->myfd); #ifndef THREADED_DNS - if (ins) - { - if (ServerInstance && ServerInstance->SE) - ServerInstance->SE->AddFd(this->myfd,true,X_ESTAB_DNS); - } + if (ins) + { + if (ServerInstance && ServerInstance->SE) + ServerInstance->SE->AddFd(this->myfd,true,X_ESTAB_DNS); + } #endif - return true; + return true; } bool DNS::ForwardLookup(const std::string &host, bool ins) { - if (ServerInstance && ServerInstance->stats) - ServerInstance->stats->statsDns++; - this->myfd = dns_getip4(host.c_str()); - if (this->myfd == -1) - { - return false; - } - log(DEBUG,"DNS: ForwardLookup, fd=%d",this->myfd); + if (ServerInstance && ServerInstance->stats) + ServerInstance->stats->statsDns++; + this->myfd = dns_getip4(host.c_str()); + if (this->myfd == -1) + { + return false; + } + log(DEBUG,"DNS: ForwardLookup, fd=%d",this->myfd); #ifndef THREADED_DNS - if (ins) - { - if (ServerInstance && ServerInstance->SE) - ServerInstance->SE->AddFd(this->myfd,true,X_ESTAB_DNS); - } + if (ins) + { + if (ServerInstance && ServerInstance->SE) + ServerInstance->SE->AddFd(this->myfd,true,X_ESTAB_DNS); + } #endif - return true; + return true; } bool DNS::ForwardLookupWithFD(const std::string &host, int &fd) { - if (ServerInstance && ServerInstance->stats) - ServerInstance->stats->statsDns++; - this->myfd = dns_getip4(host.c_str()); - fd = this->myfd; - if (this->myfd == -1) - { - return false; - } - log(DEBUG,"DNS: ForwardLookupWithFD, fd=%d",this->myfd); - if (ServerInstance && ServerInstance->SE) - ServerInstance->SE->AddFd(this->myfd,true,X_ESTAB_MODULE); - return true; + if (ServerInstance && ServerInstance->stats) + ServerInstance->stats->statsDns++; + this->myfd = dns_getip4(host.c_str()); + fd = this->myfd; + if (this->myfd == -1) + { + return false; + } + log(DEBUG,"DNS: ForwardLookupWithFD, fd=%d",this->myfd); + if (ServerInstance && ServerInstance->SE) + ServerInstance->SE->AddFd(this->myfd,true,X_ESTAB_MODULE); + return true; } bool DNS::HasResult(int fd) { - return (fd == this->myfd); + return (fd == this->myfd); } /* Only the multithreaded dns uses this poll() based @@ -782,73 +779,73 @@ bool DNS::HasResult(int fd) */ bool DNS::HasResult() { - log(DEBUG,"DNS: HasResult, fd=%d",this->myfd); - pollfd polls; - polls.fd = this->myfd; - polls.events = POLLIN; - int ret = poll(&polls,1,1); - log(DEBUG,"DNS: Hasresult returning %d",ret); - return (ret > 0); + log(DEBUG,"DNS: HasResult, fd=%d",this->myfd); + pollfd polls; + polls.fd = this->myfd; + polls.events = POLLIN; + int ret = poll(&polls,1,1); + log(DEBUG,"DNS: Hasresult returning %d",ret); + return (ret > 0); } int DNS::GetFD() { - return this->myfd; + return this->myfd; } std::string DNS::GetResult() { - log(DEBUG,"DNS: GetResult()"); - result = dns_getresult(this->myfd); - if (result) - { - if (ServerInstance && ServerInstance->stats) - ServerInstance->stats->statsDnsGood++; - dns_close(this->myfd); - this->myfd = -1; - return result; - } - else - { - if (ServerInstance && ServerInstance->stats) - ServerInstance->stats->statsDnsBad++; - if (this->myfd != -1) - { - dns_close(this->myfd); - this->myfd = -1; - } - return ""; - } + log(DEBUG,"DNS: GetResult()"); + result = dns_getresult(this->myfd); + if (result) + { + if (ServerInstance && ServerInstance->stats) + ServerInstance->stats->statsDnsGood++; + dns_close(this->myfd); + this->myfd = -1; + return result; + } + else + { + if (ServerInstance && ServerInstance->stats) + ServerInstance->stats->statsDnsBad++; + if (this->myfd != -1) + { + dns_close(this->myfd); + this->myfd = -1; + } + return ""; + } } std::string DNS::GetResultIP() { - char r[1024]; - log(DEBUG,"DNS: GetResultIP()"); - result = dns_getresult(this->myfd); - if (this->myfd != -1) - { - dns_close(this->myfd); - this->myfd = -1; - } - if (result) - { - if (ServerInstance && ServerInstance->stats) - ServerInstance->stats->statsDnsGood++; - unsigned char a = (unsigned)result[0]; - unsigned char b = (unsigned)result[1]; - unsigned char c = (unsigned)result[2]; - unsigned char d = (unsigned)result[3]; - snprintf(r,1024,"%u.%u.%u.%u",a,b,c,d); - return r; - } - else - { - if (ServerInstance && ServerInstance->stats) - ServerInstance->stats->statsDnsBad++; - log(DEBUG,"DANGER WILL ROBINSON! NXDOMAIN for forward lookup, but we got a reverse lookup!"); - return ""; - } + char r[1024]; + log(DEBUG,"DNS: GetResultIP()"); + result = dns_getresult(this->myfd); + if (this->myfd != -1) + { + dns_close(this->myfd); + this->myfd = -1; + } + if (result) + { + if (ServerInstance && ServerInstance->stats) + ServerInstance->stats->statsDnsGood++; + unsigned char a = (unsigned)result[0]; + unsigned char b = (unsigned)result[1]; + unsigned char c = (unsigned)result[2]; + unsigned char d = (unsigned)result[3]; + snprintf(r,1024,"%u.%u.%u.%u",a,b,c,d); + return r; + } + else + { + if (ServerInstance && ServerInstance->stats) + ServerInstance->stats->statsDnsBad++; + log(DEBUG,"DANGER WILL ROBINSON! NXDOMAIN for forward lookup, but we got a reverse lookup!"); + return ""; + } } @@ -876,146 +873,146 @@ std::string DNS::GetResultIP() */ void* dns_task(void* arg) { - userrec* u = (userrec*)arg; - int thisfd = u->fd; - - log(DEBUG,"DNS thread for user %s",u->nick); - DNS dns1(Config->DNSServer); - DNS dns2(Config->DNSServer); - std::string host; - std::string ip; - int iterations = 0; - - if (dns1.ReverseLookup(inet_ntoa(u->ip4),false)) - { - /* FIX: Dont make these infinite! */ - while ((!dns1.HasResult()) && (++iterations < 20)) - usleep(100); - - if (iterations < 20) - { - if (dns1.GetFD() != -1) - { - host = dns1.GetResult(); - if (host != "") - { - if (dns2.ForwardLookup(host, false)) - { - iterations = 0; - while ((!dns2.HasResult()) && (++iterations < 20)) - usleep(100); - - if (iterations < 20) - { - if (dns2.GetFD() != -1) - { - ip = dns2.GetResultIP(); - if (ip == std::string(inet_ntoa(u->ip4))) - { - if (host.length() < 65) - { - if ((fd_ref_table[thisfd] == u) && (fd_ref_table[thisfd])) - { - if (!u->dns_done) - { - strcpy(u->host,host.c_str()); - if ((fd_ref_table[thisfd] == u) && (fd_ref_table[thisfd])) - { - strcpy(u->dhost,host.c_str()); - } - } - } - } - } - } - } - } - } - } - } - } - if ((fd_ref_table[thisfd] == u) && (fd_ref_table[thisfd])) - u->dns_done = true; - log(DEBUG,"THREAD EXIT"); - return NULL; + userrec* u = (userrec*)arg; + int thisfd = u->fd; + + log(DEBUG,"DNS thread for user %s on ip %s",u->nick,insp_ntoa(u->ip4)); + DNS dns1(Config->DNSServer); + DNS dns2(Config->DNSServer); + std::string host; + std::string ip; + int iterations = 0; + + if (dns1.ReverseLookup(insp_ntoa(u->ip4),false)) + { + /* FIX: Dont make these infinite! */ + while ((!dns1.HasResult()) && (++iterations < 20)) + usleep(100); + + if (iterations < 20) + { + if (dns1.GetFD() != -1) + { + host = dns1.GetResult(); + if (host != "") + { + if (dns2.ForwardLookup(host, false)) + { + iterations = 0; + while ((!dns2.HasResult()) && (++iterations < 20)) + usleep(100); + + if (iterations < 20) + { + if (dns2.GetFD() != -1) + { + ip = dns2.GetResultIP(); + if (ip == std::string(insp_ntoa(u->ip4))) + { + if (host.length() < 65) + { + if ((fd_ref_table[thisfd] == u) && (fd_ref_table[thisfd])) + { + if (!u->dns_done) + { + strcpy(u->host,host.c_str()); + if ((fd_ref_table[thisfd] == u) && (fd_ref_table[thisfd])) + { + strcpy(u->dhost,host.c_str()); + } + } + } + } + } + } + } + } + } + } + } + } + if ((fd_ref_table[thisfd] == u) && (fd_ref_table[thisfd])) + u->dns_done = true; + log(DEBUG,"THREAD EXIT"); + return NULL; } #endif Resolver::Resolver(const std::string &source, bool forward, const std::string &dnsserver = "") : input(source), fwd(forward), server(dnsserver) { - if (this->server != "") - Query.SetNS(this->server); - else - Query.SetNS(Config->DNSServer); - - if (forward) - { - Query.ForwardLookup(input.c_str(), false); - this->fd = Query.GetFD(); - } - else - { - Query.ReverseLookup(input.c_str(), false); - this->fd = Query.GetFD(); - } - if (fd < 0) - { - log(DEBUG,"Resolver::Resolver: RESOLVER_NSDOWN"); - this->OnError(RESOLVER_NSDOWN); - ModuleException e("Resolver: Nameserver is down"); - throw e; - /* We shouldnt get here really */ - return; - } - - if (ServerInstance && ServerInstance->SE) - { - log(DEBUG,"Resolver::Resolver: this->fd=%d",this->fd); - ServerInstance->SE->AddFd(this->fd,true,X_ESTAB_CLASSDNS); - } - else - { - log(DEBUG,"Resolver::Resolver: RESOLVER_NOTREADY"); - this->OnError(RESOLVER_NOTREADY); - ModuleException e("Resolver: Core not initialized yet"); - throw e; - /* We shouldnt get here really */ - return; - } + if (this->server != "") + Query.SetNS(this->server); + else + Query.SetNS(Config->DNSServer); + + if (forward) + { + Query.ForwardLookup(input.c_str(), false); + this->fd = Query.GetFD(); + } + else + { + Query.ReverseLookup(input.c_str(), false); + this->fd = Query.GetFD(); + } + if (fd < 0) + { + log(DEBUG,"Resolver::Resolver: RESOLVER_NSDOWN"); + this->OnError(RESOLVER_NSDOWN); + ModuleException e("Resolver: Nameserver is down"); + throw e; + /* We shouldnt get here really */ + return; + } + + if (ServerInstance && ServerInstance->SE) + { + log(DEBUG,"Resolver::Resolver: this->fd=%d",this->fd); + ServerInstance->SE->AddFd(this->fd,true,X_ESTAB_CLASSDNS); + } + else + { + log(DEBUG,"Resolver::Resolver: RESOLVER_NOTREADY"); + this->OnError(RESOLVER_NOTREADY); + ModuleException e("Resolver: Core not initialized yet"); + throw e; + /* We shouldnt get here really */ + return; + } } Resolver::~Resolver() { - log(DEBUG,"Resolver::~Resolver"); - if (ServerInstance && ServerInstance->SE) - ServerInstance->SE->DelFd(this->fd); + log(DEBUG,"Resolver::~Resolver"); + if (ServerInstance && ServerInstance->SE) + ServerInstance->SE->DelFd(this->fd); } int Resolver::GetFd() { - return this->fd; + return this->fd; } bool Resolver::ProcessResult() { - log(DEBUG,"Resolver::ProcessResult"); - if (this->fwd) - result = Query.GetResultIP(); - else - result = Query.GetResult(); - - if (result != "") - { - log(DEBUG,"Resolver::OnLookupComplete(%s)",result.c_str()); - this->OnLookupComplete(result); - return true; - } - else - { - log(DEBUG,"Resolver::OnError(RESOLVER_NXDOMAIN)"); - this->OnError(RESOLVER_NXDOMAIN); - return false; - } + log(DEBUG,"Resolver::ProcessResult"); + if (this->fwd) + result = Query.GetResultIP(); + else + result = Query.GetResult(); + + if (result != "") + { + log(DEBUG,"Resolver::OnLookupComplete(%s)",result.c_str()); + this->OnLookupComplete(result); + return true; + } + else + { + log(DEBUG,"Resolver::OnError(RESOLVER_NXDOMAIN)"); + this->OnError(RESOLVER_NXDOMAIN); + return false; + } } void Resolver::OnLookupComplete(const std::string &result) @@ -1028,42 +1025,43 @@ void Resolver::OnError(ResolverError e) void dns_deal_with_classes(int fd) { - log(DEBUG,"dns_deal_with_classes(%d)",fd); - if ((fd > -1) && (dns_classes[fd])) - { - log(DEBUG,"Valid fd %d",fd); - dns_classes[fd]->ProcessResult(); - delete dns_classes[fd]; - dns_classes[fd] = NULL; - } + log(DEBUG,"dns_deal_with_classes(%d)",fd); + if ((fd > -1) && (dns_classes[fd])) + { + log(DEBUG,"Valid fd %d",fd); + dns_classes[fd]->ProcessResult(); + delete dns_classes[fd]; + dns_classes[fd] = NULL; + } } bool dns_add_class(Resolver* r) { - log(DEBUG,"dns_add_class"); - if ((r) && (r->GetFd() > -1)) - { - if (!dns_classes[r->GetFd()]) - { - log(DEBUG,"dns_add_class: added class"); - dns_classes[r->GetFd()] = r; - return true; - } - else - { - log(DEBUG,"Space occupied!"); - return false; - } - } - else - { - log(DEBUG,"Bad class"); - delete r; - return true; - } + log(DEBUG,"dns_add_class"); + if ((r) && (r->GetFd() > -1)) + { + if (!dns_classes[r->GetFd()]) + { + log(DEBUG,"dns_add_class: added class"); + dns_classes[r->GetFd()] = r; + return true; + } + else + { + log(DEBUG,"Space occupied!"); + return false; + } + } + else + { + log(DEBUG,"Bad class"); + delete r; + return true; + } } void init_dns() { - memset(dns_classes,0,sizeof(dns_classes)); + memset(dns_classes,0,sizeof(dns_classes)); } + |