/src/irc_res.c
C | 936 lines | 644 code | 98 blank | 194 comment | 122 complexity | 0d2ec3a0cc3c17097b698ee35ebc1d61 MD5 | raw file
Possible License(s): GPL-2.0, BSD-3-Clause
- /*
- * A rewrite of Darren Reeds original res.c As there is nothing
- * left of Darrens original code, this is now licensed by the hybrid group.
- * (Well, some of the function names are the same, and bits of the structs..)
- * You can use it where it is useful, free even. Buy us a beer and stuff.
- *
- * The authors takes no responsibility for any damage or loss
- * of property which results from the use of this software.
- *
- * $Id: irc_res.c 465 2006-12-28 02:31:10Z jon $
- *
- * July 1999 - Rewrote a bunch of stuff here. Change hostent builder code,
- * added callbacks and reference counting of returned hostents.
- * --Bleep (Thomas Helvey <tomh@inxpress.net>)
- *
- * This was all needlessly complicated for irc. Simplified. No more hostent
- * All we really care about is the IP -> hostname mappings. Thats all.
- *
- * Apr 28, 2003 --cryogen and Dianora
- */
- #include "stdinc.h"
- #include "tools.h"
- #include "client.h"
- #include "list.h"
- #include "common.h"
- #include "event.h"
- #include "irc_string.h"
- #include "sprintf_irc.h"
- #include "ircd.h"
- #include "numeric.h"
- #include "restart.h"
- #include "fdlist.h"
- #include "fileio.h" /* for fbopen / fbclose / fbputs */
- #include "s_bsd.h"
- #include "s_log.h"
- #include "send.h"
- #include "memory.h"
- #include "irc_res.h"
- #include "irc_reslib.h"
- #include "irc_getnameinfo.h"
- #if (CHAR_BIT != 8)
- #error this code needs to be able to address individual octets
- #endif
- static PF res_readreply;
- #define MAXPACKET 1024 /* rfc sez 512 but we expand names so ... */
- #define RES_MAXALIASES 35 /* maximum aliases allowed */
- #define RES_MAXADDRS 35 /* maximum addresses allowed */
- #define AR_TTL 600 /* TTL in seconds for dns cache entries */
- /* RFC 1104/1105 wasn't very helpful about what these fields
- * should be named, so for now, we'll just name them this way.
- * we probably should look at what named calls them or something.
- */
- #define TYPE_SIZE (size_t)2
- #define CLASS_SIZE (size_t)2
- #define TTL_SIZE (size_t)4
- #define RDLENGTH_SIZE (size_t)2
- #define ANSWER_FIXED_SIZE (TYPE_SIZE + CLASS_SIZE + TTL_SIZE + RDLENGTH_SIZE)
- typedef enum
- {
- REQ_IDLE, /* We're doing not much at all */
- REQ_PTR, /* Looking up a PTR */
- REQ_A, /* Looking up an A, possibly because AAAA failed */
- #ifdef IPV6
- REQ_AAAA, /* Looking up an AAAA */
- #endif
- REQ_CNAME, /* We got a CNAME in response, we better get a real answer next */
- REQ_INT /* ip6.arpa failed, falling back to ip6.int */
- } request_state;
- struct reslist
- {
- dlink_node node;
- int id;
- int sent; /* number of requests sent */
- request_state state; /* State the resolver machine is in */
- time_t ttl;
- char type;
- char retries; /* retry counter */
- char sends; /* number of sends (>1 means resent) */
- char resend; /* send flag. 0 == dont resend */
- time_t sentat;
- time_t timeout;
- struct irc_ssaddr addr;
- char *name;
- struct DNSQuery *query; /* query callback for this request */
- };
- static fde_t ResolverFileDescriptor;
- static dlink_list request_list = { NULL, NULL, 0 };
- static void rem_request(struct reslist *request);
- static struct reslist *make_request(struct DNSQuery *query);
- static void do_query_name(struct DNSQuery *query, const char *name, struct reslist *request, int);
- static void do_query_number(struct DNSQuery *query,
- const struct irc_ssaddr *, struct reslist *request);
- static void query_name(const char *name, int query_class, int query_type, struct reslist *request);
- static int send_res_msg(const char *buf, int len, int count);
- static void resend_query(struct reslist *request);
- static int proc_answer(struct reslist *request, HEADER * header, char *, char *);
- static struct reslist *find_id(int id);
- static struct DNSReply *make_dnsreply(struct reslist *request);
- extern struct irc_ssaddr irc_nsaddr_list[IRCD_MAXNS];
- extern int irc_nscount;
- extern char irc_domain[HOSTLEN + 1];
- /*
- * int
- * res_ourserver(inp)
- * looks up "inp" in irc_nsaddr_list[]
- * returns:
- * 0 : not found
- * >0 : found
- * author:
- * paul vixie, 29may94
- * revised for ircd, cryogen(stu) may03
- */
- static int
- res_ourserver(const struct irc_ssaddr *inp)
- {
- #ifdef IPV6
- struct sockaddr_in6 *v6;
- struct sockaddr_in6 *v6in = (struct sockaddr_in6 *) inp;
- #endif
- struct sockaddr_in *v4;
- struct sockaddr_in *v4in = (struct sockaddr_in *) inp;
- int ns;
- for(ns = 0; ns < irc_nscount; ns++)
- {
- const struct irc_ssaddr *srv = &irc_nsaddr_list[ns];
- #ifdef IPV6
- v6 = (struct sockaddr_in6 *) srv;
- #endif
- v4 = (struct sockaddr_in *) srv;
- /* could probably just memcmp(srv, inp, srv.ss_len) here
- * but we'll air on the side of caution - stu
- *
- */
- switch (srv->ss.ss_family)
- {
- #ifdef IPV6
- case AF_INET6:
- if(srv->ss.ss_family == inp->ss.ss_family)
- if(v6->sin6_port == v6in->sin6_port)
- if((memcmp(&v6->sin6_addr.s6_addr, &v6in->sin6_addr.s6_addr,
- sizeof(struct in6_addr)) == 0) ||
- (memcmp(&v6->sin6_addr.s6_addr, &in6addr_any,
- sizeof(struct in6_addr)) == 0))
- return (1);
- break;
- #endif
- case AF_INET:
- if(srv->ss.ss_family == inp->ss.ss_family)
- if(v4->sin_port == v4in->sin_port)
- if((v4->sin_addr.s_addr == INADDR_ANY) ||
- (v4->sin_addr.s_addr == v4in->sin_addr.s_addr))
- return (1);
- break;
- default:
- break;
- }
- }
- return (0);
- }
- /*
- * timeout_query_list - Remove queries from the list which have been
- * there too long without being resolved.
- */
- static time_t
- timeout_query_list(time_t now)
- {
- dlink_node *ptr;
- dlink_node *next_ptr;
- struct reslist *request;
- time_t next_time = 0;
- time_t timeout = 0;
- DLINK_FOREACH_SAFE(ptr, next_ptr, request_list.head)
- {
- request = ptr->data;
- timeout = request->sentat + request->timeout;
- if(now >= timeout)
- {
- if(--request->retries <= 0)
- {
- (*request->query->callback) (request->query->ptr, NULL);
- rem_request(request);
- continue;
- }
- else
- {
- request->sentat = now;
- request->timeout += request->timeout;
- resend_query(request);
- }
- }
- if((next_time == 0) || timeout < next_time)
- {
- next_time = timeout;
- }
- }
- return ((next_time > now) ? next_time : (now + AR_TTL));
- }
- /*
- * timeout_resolver - check request list
- */
- static void
- timeout_resolver(void *notused)
- {
- timeout_query_list(CurrentTime);
- }
- /*
- * start_resolver - do everything we need to read the resolv.conf file
- * and initialize the resolver file descriptor if needed
- */
- static void
- start_resolver(void)
- {
- irc_res_init();
- if(!ResolverFileDescriptor.flags.open)
- {
- if(comm_open(&ResolverFileDescriptor, irc_nsaddr_list[0].ss.ss_family,
- SOCK_DGRAM, 0, "Resolver socket") == -1)
- return;
- /* At the moment, the resolver FD data is global .. */
- comm_setselect(&ResolverFileDescriptor, COMM_SELECT_READ, res_readreply, NULL, 0);
- eventAdd("timeout_resolver", timeout_resolver, NULL, 1);
- }
- }
- /*
- * init_resolver - initialize resolver and resolver library
- */
- void
- init_resolver(void)
- {
- #ifdef HAVE_SRAND48
- srand48(CurrentTime);
- #endif
- memset(&ResolverFileDescriptor, 0, sizeof(fde_t));
- start_resolver();
- }
- /*
- * restart_resolver - reread resolv.conf, reopen socket
- */
- void
- restart_resolver(void)
- {
- fd_close(&ResolverFileDescriptor);
- eventDelete(timeout_resolver, NULL); /* -ddosen */
- start_resolver();
- }
- /*
- * add_local_domain - Add the domain to hostname, if it is missing
- * (as suggested by eps@TOASTER.SFSU.EDU)
- */
- void
- add_local_domain(char *hname, size_t size)
- {
- /* try to fix up unqualified names
- */
- if(strchr(hname, '.') == NULL)
- {
- if(irc_domain[0])
- {
- size_t len = strlen(hname);
- if((strlen(irc_domain) + len + 2) < size)
- {
- hname[len++] = '.';
- strcpy(hname + len, irc_domain);
- }
- }
- }
- }
- /*
- * rem_request - remove a request from the list.
- * This must also free any memory that has been allocated for
- * temporary storage of DNS results.
- */
- static void
- rem_request(struct reslist *request)
- {
- dlinkDelete(&request->node, &request_list);
- MyFree(request->name);
- MyFree(request);
- }
- /*
- * make_request - Create a DNS request record for the server.
- */
- static struct reslist *
- make_request(struct DNSQuery *query)
- {
- struct reslist *request;
- request = (struct reslist *) MyMalloc(sizeof(struct reslist));
- request->sentat = CurrentTime;
- request->retries = 2;
- request->resend = 1;
- request->timeout = 4; /* start at 4 and exponential inc. */
- request->query = query;
- request->state = REQ_IDLE;
- dlinkAdd(request, &request->node, &request_list);
- return (request);
- }
- /*
- * delete_resolver_queries - cleanup outstanding queries
- * for which there no longer exist clients or conf lines.
- */
- void
- delete_resolver_queries(const struct DNSQuery *query)
- {
- dlink_node *ptr;
- dlink_node *next_ptr;
- struct reslist *request;
- DLINK_FOREACH_SAFE(ptr, next_ptr, request_list.head)
- {
- if((request = ptr->data) != NULL)
- {
- if(query == request->query)
- rem_request(request);
- }
- }
- }
- /*
- * send_res_msg - sends msg to all nameservers found in the "_res" structure.
- * This should reflect /etc/resolv.conf. We will get responses
- * which arent needed but is easier than checking to see if nameserver
- * isnt present. Returns number of messages successfully sent to
- * nameservers or -1 if no successful sends.
- */
- static int
- send_res_msg(const char *msg, int len, int rcount)
- {
- int i;
- int sent = 0;
- int max_queries = IRCD_MIN(irc_nscount, rcount);
- /* RES_PRIMARY option is not implemented
- * if (res.options & RES_PRIMARY || 0 == max_queries)
- */
- if(max_queries == 0)
- max_queries = 1;
- for(i = 0; i < max_queries; i++)
- {
- if(sendto(ResolverFileDescriptor.fd, msg, len, 0,
- (struct sockaddr *) &(irc_nsaddr_list[i]),
- irc_nsaddr_list[i].ss_len) == len)
- ++sent;
- }
- return (sent);
- }
- /*
- * find_id - find a dns request id (id is determined by dn_mkquery)
- */
- static struct reslist *
- find_id(int id)
- {
- dlink_node *ptr;
- struct reslist *request;
- DLINK_FOREACH(ptr, request_list.head)
- {
- request = ptr->data;
- if(request->id == id)
- return (request);
- }
- return (NULL);
- }
- /*
- * gethost_byname_type - get host address from name
- *
- */
- void
- gethost_byname_type(const char *name, struct DNSQuery *query, int type)
- {
- assert(name != 0);
- do_query_name(query, name, NULL, type);
- }
- /*
- * gethost_byname - wrapper for _type - send T_AAAA first if IPV6 supported
- */
- void
- gethost_byname(const char *name, struct DNSQuery *query)
- {
- #ifdef IPV6
- gethost_byname_type(name, query, T_AAAA);
- #else
- gethost_byname_type(name, query, T_A);
- #endif
- }
- /*
- * gethost_byaddr - get host name from address
- */
- void
- gethost_byaddr(const struct irc_ssaddr *addr, struct DNSQuery *query)
- {
- do_query_number(query, addr, NULL);
- }
- /*
- * do_query_name - nameserver lookup name
- */
- static void
- do_query_name(struct DNSQuery *query, const char *name, struct reslist *request, int type)
- {
- char host_name[HOSTLEN + 1];
- strlcpy(host_name, name, HOSTLEN);
- add_local_domain(host_name, HOSTLEN);
- if(request == NULL)
- {
- request = make_request(query);
- request->name = (char *) MyMalloc(strlen(host_name) + 1);
- request->type = type;
- strcpy(request->name, host_name);
- #ifdef IPV6
- if(type == T_A)
- request->state = REQ_A;
- else
- request->state = REQ_AAAA;
- #else
- request->state = REQ_A;
- #endif
- }
- request->type = type;
- query_name(host_name, C_IN, type, request);
- }
- /*
- * do_query_number - Use this to do reverse IP# lookups.
- */
- static void
- do_query_number(struct DNSQuery *query, const struct irc_ssaddr *addr, struct reslist *request)
- {
- char ipbuf[128];
- const unsigned char *cp;
- #ifdef IPV6
- const char *intarpa;
- #endif
- if(addr->ss.ss_family == AF_INET)
- {
- struct sockaddr_in *v4 = (struct sockaddr_in *) addr;
- cp = (const unsigned char *) &v4->sin_addr.s_addr;
- ircsprintf(ipbuf, "%u.%u.%u.%u.in-addr.arpa.",
- (unsigned int) (cp[3]), (unsigned int) (cp[2]),
- (unsigned int) (cp[1]), (unsigned int) (cp[0]));
- }
- #ifdef IPV6
- else if(addr->ss.ss_family == AF_INET6)
- {
- struct sockaddr_in6 *v6 = (struct sockaddr_in6 *) addr;
- cp = (const unsigned char *) &v6->sin6_addr.s6_addr;
- if(request != NULL && request->state == REQ_INT)
- intarpa = "int";
- else
- intarpa = "arpa";
- (void) sprintf(ipbuf, "%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x."
- "%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.ip6.%s.",
- (unsigned int) (cp[15] & 0xf), (unsigned int) (cp[15] >> 4),
- (unsigned int) (cp[14] & 0xf), (unsigned int) (cp[14] >> 4),
- (unsigned int) (cp[13] & 0xf), (unsigned int) (cp[13] >> 4),
- (unsigned int) (cp[12] & 0xf), (unsigned int) (cp[12] >> 4),
- (unsigned int) (cp[11] & 0xf), (unsigned int) (cp[11] >> 4),
- (unsigned int) (cp[10] & 0xf), (unsigned int) (cp[10] >> 4),
- (unsigned int) (cp[9] & 0xf), (unsigned int) (cp[9] >> 4),
- (unsigned int) (cp[8] & 0xf), (unsigned int) (cp[8] >> 4),
- (unsigned int) (cp[7] & 0xf), (unsigned int) (cp[7] >> 4),
- (unsigned int) (cp[6] & 0xf), (unsigned int) (cp[6] >> 4),
- (unsigned int) (cp[5] & 0xf), (unsigned int) (cp[5] >> 4),
- (unsigned int) (cp[4] & 0xf), (unsigned int) (cp[4] >> 4),
- (unsigned int) (cp[3] & 0xf), (unsigned int) (cp[3] >> 4),
- (unsigned int) (cp[2] & 0xf), (unsigned int) (cp[2] >> 4),
- (unsigned int) (cp[1] & 0xf), (unsigned int) (cp[1] >> 4),
- (unsigned int) (cp[0] & 0xf), (unsigned int) (cp[0] >> 4), intarpa);
- }
- #endif
- if(request == NULL)
- {
- request = make_request(query);
- request->type = T_PTR;
- memcpy(&request->addr, addr, sizeof(struct irc_ssaddr));
- request->name = (char *) MyMalloc(HOSTLEN + 1);
- }
- query_name(ipbuf, C_IN, T_PTR, request);
- }
- /*
- * query_name - generate a query based on class, type and name.
- */
- static void
- query_name(const char *name, int query_class, int type, struct reslist *request)
- {
- char buf[MAXPACKET];
- int request_len = 0;
- memset(buf, 0, sizeof(buf));
- if((request_len = irc_res_mkquery(name, query_class, type,
- (unsigned char *) buf, sizeof(buf))) > 0)
- {
- HEADER *header = (HEADER *) buf;
- #ifndef HAVE_LRAND48
- int k = 0;
- struct timeval tv;
- #endif
- /*
- * generate an unique id
- * NOTE: we don't have to worry about converting this to and from
- * network byte order, the nameserver does not interpret this value
- * and returns it unchanged
- */
- #ifdef HAVE_LRAND48
- do
- {
- header->id = (header->id + lrand48()) & 0xffff;
- }
- while(find_id(header->id));
- #else
- gettimeofday(&tv, NULL);
- do
- {
- header->id = (header->id + k + tv.tv_usec) & 0xffff;
- k++;
- }
- while(find_id(header->id));
- #endif /* HAVE_LRAND48 */
- request->id = header->id;
- ++request->sends;
- request->sent += send_res_msg(buf, request_len, request->sends);
- }
- }
- static void
- resend_query(struct reslist *request)
- {
- if(request->resend == 0)
- return;
- switch (request->type)
- {
- case T_PTR:
- do_query_number(NULL, &request->addr, request);
- break;
- case T_A:
- do_query_name(NULL, request->name, request, request->type);
- break;
- #ifdef IPV6
- case T_AAAA:
- /* didnt work, try A */
- if(request->state == REQ_AAAA)
- do_query_name(NULL, request->name, request, T_A);
- #endif
- default:
- break;
- }
- }
- /*
- * proc_answer - process name server reply
- */
- static int
- proc_answer(struct reslist *request, HEADER * header, char *buf, char *eob)
- {
- char hostbuf[HOSTLEN + 100]; /* working buffer */
- unsigned char *current; /* current position in buf */
- int query_class; /* answer class */
- int type; /* answer type */
- int n; /* temp count */
- int rd_length;
- struct sockaddr_in *v4; /* conversion */
- #ifdef IPV6
- struct sockaddr_in6 *v6;
- #endif
- current = (unsigned char *) buf + sizeof(HEADER);
- for(; header->qdcount > 0; --header->qdcount)
- {
- if((n = irc_dn_skipname(current, (unsigned char *) eob)) < 0)
- break;
- current += (size_t) n + QFIXEDSZ;
- }
- /*
- * process each answer sent to us blech.
- */
- while(header->ancount > 0 && (char *) current < eob)
- {
- header->ancount--;
- n = irc_dn_expand((unsigned char *) buf, (unsigned char *) eob, current,
- hostbuf, sizeof(hostbuf));
- if(n < 0)
- {
- /*
- * broken message
- */
- return (0);
- }
- else if(n == 0)
- {
- /*
- * no more answers left
- */
- return (0);
- }
- hostbuf[HOSTLEN] = '\0';
- /* With Address arithmetic you have to be very anal
- * this code was not working on alpha due to that
- * (spotted by rodder/jailbird/dianora)
- */
- current += (size_t) n;
- if(!(((char *) current + ANSWER_FIXED_SIZE) < eob))
- break;
- type = irc_ns_get16(current);
- current += TYPE_SIZE;
- query_class = irc_ns_get16(current);
- current += CLASS_SIZE;
- request->ttl = irc_ns_get32(current);
- current += TTL_SIZE;
- rd_length = irc_ns_get16(current);
- current += RDLENGTH_SIZE;
- /*
- * Wait to set request->type until we verify this structure
- */
- switch (type)
- {
- case T_A:
- if(request->type != T_A)
- return (0);
- /*
- * check for invalid rd_length or too many addresses
- */
- if(rd_length != sizeof(struct in_addr))
- return (0);
- v4 = (struct sockaddr_in *) &request->addr;
- request->addr.ss_len = sizeof(struct sockaddr_in);
- v4->sin_family = AF_INET;
- memcpy(&v4->sin_addr, current, sizeof(struct in_addr));
- return (1);
- break;
- #ifdef IPV6
- case T_AAAA:
- if(request->type != T_AAAA)
- return (0);
- if(rd_length != sizeof(struct in6_addr))
- return (0);
- request->addr.ss_len = sizeof(struct sockaddr_in6);
- v6 = (struct sockaddr_in6 *) &request->addr;
- v6->sin6_family = AF_INET6;
- memcpy(&v6->sin6_addr, current, sizeof(struct in6_addr));
- return (1);
- break;
- #endif
- case T_PTR:
- if(request->type != T_PTR)
- return (0);
- n = irc_dn_expand((unsigned char *) buf, (unsigned char *) eob,
- current, hostbuf, sizeof(hostbuf));
- if(n < 0)
- return (0); /* broken message */
- else if(n == 0)
- return (0); /* no more answers left */
- strlcpy(request->name, hostbuf, HOSTLEN);
- return (1);
- break;
- case T_CNAME: /* first check we already havent started looking
- into a cname */
- if(request->type != T_PTR)
- return (0);
- if(request->state == REQ_CNAME)
- {
- n = irc_dn_expand((unsigned char *) buf, (unsigned char *) eob,
- current, hostbuf, sizeof(hostbuf));
- if(n < 0)
- return (0);
- return (1);
- }
- request->state = REQ_CNAME;
- current += rd_length;
- break;
- default:
- /* XXX I'd rather just throw away the entire bogus thing
- * but its possible its just a broken nameserver with still
- * valid answers. But lets do some rudimentary logging for now...
- */
- ilog(L_ERROR, "irc_res.c bogus type %d", type);
- break;
- }
- }
- return (1);
- }
- /*
- * res_readreply - read a dns reply from the nameserver and process it.
- */
- static void
- res_readreply(fde_t * fd, void *data)
- {
- char buf[sizeof(HEADER) + MAXPACKET]
- /* Sparc and alpha need 16bit-alignment for accessing header->id
- * (which is uint16_t). Because of the header = (HEADER*) buf;
- * lateron, this is neeeded. --FaUl
- */
- #if defined(__sparc__) || defined(__alpha__)
- __attribute__ ((aligned(16)))
- #endif
- ;
- HEADER *header;
- struct reslist *request = NULL;
- struct DNSReply *reply = NULL;
- int rc;
- int answer_count;
- socklen_t len = sizeof(struct irc_ssaddr);
- struct irc_ssaddr lsin;
- rc = recvfrom(fd->fd, buf, sizeof(buf), 0, (struct sockaddr *) &lsin, &len);
- /* Re-schedule a read *after* recvfrom, or we'll be registering
- * interest where it'll instantly be ready for read :-) -- adrian
- */
- comm_setselect(fd, COMM_SELECT_READ, res_readreply, NULL, 0);
- /* Better to cast the sizeof instead of rc */
- if(rc <= (int) (sizeof(HEADER)))
- return;
- /*
- * convert DNS reply reader from Network byte order to CPU byte order.
- */
- header = (HEADER *) buf;
- header->ancount = ntohs(header->ancount);
- header->qdcount = ntohs(header->qdcount);
- header->nscount = ntohs(header->nscount);
- header->arcount = ntohs(header->arcount);
- /*
- * response for an id which we have already received an answer for
- * just ignore this response.
- */
- if(0 == (request = find_id(header->id)))
- return;
- /*
- * check against possibly fake replies
- */
- if(!res_ourserver(&lsin))
- return;
- if((header->rcode != NO_ERRORS) || (header->ancount == 0))
- {
- if(NXDOMAIN == header->rcode)
- {
- /*
- * If we havent already tried this, and we're looking up AAAA, try A
- * now
- */
- #ifdef IPV6
- if(request->state == REQ_AAAA && request->type == T_AAAA)
- {
- request->timeout += 4;
- resend_query(request);
- }
- else if(request->type == T_PTR && request->state != REQ_INT &&
- request->addr.ss.ss_family == AF_INET6)
- {
- request->state = REQ_INT;
- request->timeout += 4;
- request->retries--;
- resend_query(request);
- }
- else /* It's NXDOMAIN but not IPV6 */
- #endif
- {
- /*
- * If a bad error was returned, stop here and don't
- * send any more (no retries granted).
- */
- (*request->query->callback) (request->query->ptr, NULL);
- rem_request(request);
- }
- }
- else /* Some other error other than NXDOMAIN */
- {
- /*
- * If a bad error was returned, stop here and don't
- * send any more (no retries granted).
- */
- (*request->query->callback) (request->query->ptr, NULL);
- rem_request(request);
- }
- return;
- }
- /*
- * If this fails there was an error decoding the received packet,
- * try it again and hope it works the next time.
- */
- answer_count = proc_answer(request, header, buf, buf + rc);
- if(answer_count)
- {
- if(request->type == T_PTR)
- {
- if(request->name == NULL)
- {
- /*
- * got a PTR response with no name, something bogus is happening
- * don't bother trying again, the client address doesn't resolve
- */
- (*request->query->callback) (request->query->ptr, reply);
- rem_request(request);
- return;
- }
- /*
- * Lookup the 'authoritative' name that we were given for the
- * ip#.
- *
- */
- #ifdef IPV6
- if(request->addr.ss.ss_family == AF_INET6)
- gethost_byname_type(request->name, request->query, T_AAAA);
- else
- #endif
- gethost_byname_type(request->name, request->query, T_A);
- rem_request(request);
- }
- else
- {
- /*
- * got a name and address response, client resolved
- */
- reply = make_dnsreply(request);
- (*request->query->callback) (request->query->ptr, reply);
- MyFree(reply);
- rem_request(request);
- }
- }
- else if(!request->sent)
- {
- /* XXX - we got a response for a query we didn't send with a valid id?
- * this should never happen, bail here and leave the client unresolved
- */
- assert(0);
- /* XXX don't leak it */
- rem_request(request);
- }
- }
- static struct DNSReply *
- make_dnsreply(struct reslist *request)
- {
- struct DNSReply *cp;
- assert(request != 0);
- cp = (struct DNSReply *) MyMalloc(sizeof(struct DNSReply));
- cp->h_name = request->name;
- memcpy(&cp->addr, &request->addr, sizeof(cp->addr));
- return (cp);
- }
- void
- report_dns_servers(struct Client *source_p)
- {
- int i;
- char ipaddr[HOSTIPLEN];
- for(i = 0; i < irc_nscount; i++)
- {
- irc_getnameinfo((struct sockaddr *) &(irc_nsaddr_list[i]),
- irc_nsaddr_list[i].ss_len, ipaddr, HOSTIPLEN, NULL, 0,
- NI_NUMERICHOST);
- sendto_one(source_p, form_str(RPL_STATSALINE), me.name, source_p->name, ipaddr);
- }
- }