* The authors takes no responsibility for any damage or loss
* of property which results from the use of this software.
*
- * $Id$
- *
* 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.
+ * All we really care about is the IP -> hostname mappings. Thats all.
*
* Apr 28, 2003 --cryogen and Dianora
*/
+/** @file
+ * @brief IRC resolver functions.
+ * @version $Id$
+ */
#include "client.h"
#include "ircd_alloc.h"
#include "ircd.h"
#include "numeric.h"
#include "fileio.h" /* for fbopen / fbclose / fbputs */
+#include "random.h"
#include "s_bsd.h"
+#include "s_debug.h"
#include "s_stats.h"
#include "send.h"
#include "sys.h"
#include "res.h"
#include "ircd_reslib.h"
-#include "ircd_addrinfo.h"
-#include <assert.h>
+/* #include <assert.h> -- Now using assert in ircd_log.h */
#include <string.h>
#include <sys/time.h>
#include <sys/socket.h>
#error this code needs to be able to address individual octets
#endif
+/** Resolver UDP socket. */
static struct Socket res_socket;
+/** Next DNS lookup timeout. */
static struct Timer res_timeout;
+/** Check for whether the resolver has been initialized yet. */
+#define resolver_started() (request_list.next != NULL)
-#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 */
+/** Maximum DNS packet length.
+ * RFC says 512, but we add extra for expanded names.
+ */
+#define MAXPACKET 1024
+#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.
*/
+/** Size of TYPE field of a DNS RR header. */
#define TYPE_SIZE (size_t)2
+/** Size of CLASS field of a DNS RR header. */
#define CLASS_SIZE (size_t)2
+/** Size of TTL field of a DNS RR header. */
#define TTL_SIZE (size_t)4
+/** Size of RDLENGTH field of a DNS RR header. */
#define RDLENGTH_SIZE (size_t)2
+/** Size of fixed-format part of a DNS RR header. */
#define ANSWER_FIXED_SIZE (TYPE_SIZE + CLASS_SIZE + TTL_SIZE + RDLENGTH_SIZE)
-typedef enum
+/** Current request state. */
+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 */
+ 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. */
+ REQ_AAAA, /**< Looking up an AAAA. */
+ 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;
+/** Doubly linked list node. */
struct dlink
{
- struct dlink *prev;
- struct dlink *next;
+ struct dlink *prev; /**< Previous element in list. */
+ struct dlink *next; /**< Next element in list. */
};
-struct reslist
+/** A single resolver request.
+ * (Do not be fooled by the "list" in the name.)
+ */
+struct reslist
{
- struct dlink 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 */
+ struct dlink node; /**< Doubly linked list node. */
+ int id; /**< Request ID (from request header). */
+ int sent; /**< Number of requests sent. */
+ request_state state; /**< State the resolver machine is in. */
+ char type; /**< Current request type. */
+ char retries; /**< Retry counter. */
+ char sends; /**< Number of sends (>1 means resent). */
+ char resend; /**< Send flag; 0 == dont resend. */
+ time_t sentat; /**< Timestamp we last sent this request. */
+ time_t timeout; /**< When this request times out. */
+ struct irc_in_addr addr; /**< Address for this request. */
+ char *name; /**< Hostname for this request. */
+ struct DNSQuery query; /**< Query callback for this request. */
};
+/** Base of request list. */
static struct dlink request_list;
static void rem_request(struct reslist *request);
static void do_query_name(const struct DNSQuery *query,
const char* name, struct reslist *request, int);
static void do_query_number(const struct DNSQuery *query,
- const struct irc_ssaddr *,
+ const struct irc_in_addr *,
struct reslist *request);
-static void query_name(const char *name, int query_class, int query_type,
+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 void res_readreply(struct Event *ev);
static void timeout_resolver(struct Event *notused);
-extern struct irc_ssaddr irc_nsaddr_list[IRCD_MAXNS];
+extern struct irc_sockaddr irc_nsaddr_list[IRCD_MAXNS];
extern int irc_nscount;
extern char irc_domain[HOSTLEN];
-/*
- * 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
+struct irc_sockaddr ResolverAddr;
+
+/** Check whether \a inp is a nameserver we use.
+ * @param[in] inp Nameserver address.
+ * @return Non-zero if we trust \a inp; zero if not.
*/
static int
-res_ourserver(const struct irc_ssaddr *inp)
+res_ourserver(const struct irc_sockaddr *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;
- }
- }
+ if (!irc_in_addr_cmp(&inp->addr, &irc_nsaddr_list[ns].addr)
+ && inp->port == irc_nsaddr_list[ns].port)
+ return 1;
return(0);
}
-/*
- * start_resolver - do everything we need to read the resolv.conf file
- * and initialize the resolver file descriptor if needed
+/** Start (or re-start) resolver.
+ * This means read resolv.conf, initialize the list of pending
+ * requests, open the resolver socket and initialize its timeout.
*/
-static void
-start_resolver(void)
+void
+restart_resolver(void)
{
irc_res_init();
if (!request_list.next)
- request_list.next = request_list.prev = &request_list;
+ request_list.next = request_list.prev = &request_list;
if (!s_active(&res_socket))
{
+ struct irc_sockaddr *local;
int fd;
- fd = socket(irc_nsaddr_list[0].ss.ss_family, SOCK_DGRAM, 0);
- if (fd < 0) {} /* TODO: bail on socket() failure */
- if (!os_set_nonblocking(fd)) {} /* TODO: bail on failure */
+ local = irc_in_addr_valid(&ResolverAddr) ? &ResolverAddr : &VirtualHost;
+ fd = os_socket(local, SOCK_DGRAM, "Resolver UDP socket");
+ if (fd < 0) return;
if (!socket_add(&res_socket, res_readreply, NULL, SS_DATAGRAM,
- SOCK_EVENT_READABLE, fd)) {} /* TODO: bail on socket_add() failure */
+ SOCK_EVENT_READABLE, fd)) return;
timer_init(&res_timeout);
- timer_add(&res_timeout, timeout_resolver, NULL, TT_PERIODIC, 1);
}
}
-/*
- * init_resolver - initialize resolver and resolver library
- */
-int
-init_resolver(void)
-{
-#ifdef LRAND48
- srand48(CurrentTime);
-#endif
- start_resolver();
- return(s_fd(&res_socket));
-}
-
-/*
- * restart_resolver - reread resolv.conf, reopen socket
- */
-void
-restart_resolver(void)
-{
- start_resolver();
-}
-
-/*
- * add_local_domain - Add the domain to hostname, if it is missing
- * (as suggested by eps@TOASTER.SFSU.EDU)
+/** Append local domain to hostname if needed.
+ * If \a hname does not contain any '.'s, append #irc_domain to it.
+ * @param[in,out] hname Hostname to check.
+ * @param[in] size Length of \a hname buffer.
*/
void
add_local_domain(char* hname, size_t size)
}
}
-/*
- * remove_dlink - remove a link from a doubly linked list
- */
-static void
-remove_dlink(struct dlink *node)
-{
- node->prev->next = node->next;
- node->next->prev = node->prev;
-}
-
-/*
- * add_dlink - add a link to a doubly linked list
+/** Add a node to a doubly linked list.
+ * @param[in,out] node Node to add to list.
+ * @param[in,out] next Add \a node before this one.
*/
static void
add_dlink(struct dlink *node, struct dlink *next)
node->next->prev = node;
}
-/*
- * rem_request - remove a request from the list.
- * This must also free any memory that has been allocated for
- * temporary storage of DNS results.
+/** Remove a request from the list and free it.
+ * @param[in] request Node to free.
*/
static void
rem_request(struct reslist *request)
{
- remove_dlink(&request->node);
+ /* remove from dlist */
+ request->node.prev->next = request->node.next;
+ request->node.next->prev = request->node.prev;
+ /* free memory */
MyFree(request->name);
MyFree(request);
}
-/*
- * make_request - Create a DNS request record for the server.
+/** Create a DNS request record for the server.
+ * @param[in] query Callback information for caller.
+ * @return Newly allocated and linked-in reslist.
*/
static struct reslist *
make_request(const struct DNSQuery* query)
{
struct reslist *request;
+ if (!resolver_started())
+ restart_resolver();
+
request = (struct reslist *)MyMalloc(sizeof(struct reslist));
memset(request, 0, sizeof(struct reslist));
+ request->state = REQ_IDLE;
request->sentat = CurrentTime;
- request->retries = 3;
+ request->retries = feature_int(FEAT_IRCD_RES_RETRIES);
request->resend = 1;
- request->timeout = 4; /* start at 4 and exponential inc. */
+ request->timeout = feature_int(FEAT_IRCD_RES_TIMEOUT);
memset(&request->addr, 0, sizeof(request->addr));
- request->query.vptr = query->vptr;
- request->query.callback = query->callback;
- request->state = REQ_IDLE;
+ memcpy(&request->query, query, sizeof(request->query));
add_dlink(&request->node, &request_list);
return(request);
}
-/*
- * timeout_query_list - Remove queries from the list which have been
- * there too long without being resolved.
+/** Make sure that a timeout event will happen by the given time.
+ * @param[in] when Latest time for timeout to run.
+ */
+static void
+check_resolver_timeout(time_t when)
+{
+ if (when > CurrentTime + AR_TTL)
+ when = CurrentTime + AR_TTL;
+ if (!t_active(&res_timeout))
+ timer_add(&res_timeout, timeout_resolver, NULL, TT_ABSOLUTE, when);
+ else if (when < t_expire(&res_timeout))
+ timer_chg(&res_timeout, TT_ABSOLUTE, when);
+}
+
+/** Drop pending DNS lookups which have timed out.
+ * @param[in] notused Timer event data (ignored).
*/
-static time_t
-timeout_query_list(time_t now)
+static void
+timeout_resolver(struct Event *notused)
{
struct dlink *ptr, *next_ptr;
struct reslist *request;
request = (struct reslist*)ptr;
timeout = request->sentat + request->timeout;
- if (now >= timeout)
+ if (CurrentTime >= timeout)
{
if (--request->retries <= 0)
{
+ Debug((DEBUG_DNS, "Request %p out of retries; destroying", request));
(*request->query.callback)(request->query.vptr, 0);
rem_request(request);
continue;
}
else
{
- request->sentat = now;
+ request->sentat = CurrentTime;
request->timeout += request->timeout;
resend_query(request);
}
}
}
- return((next_time > now) ? next_time : (now + AR_TTL));
-}
-
-/*
- * timeout_resolver - check request list
- */
-static void
-timeout_resolver(struct Event *notused)
-{
- timeout_query_list(CurrentTime);
+ if (next_time <= CurrentTime)
+ next_time = CurrentTime + AR_TTL;
+ check_resolver_timeout(next_time);
}
-/*
- * delete_resolver_queries - cleanup outstanding queries
- * for which there no longer exist clients or conf lines.
+/** Drop queries that are associated with a particular pointer.
+ * This is used to clean up lookups for clients or conf blocks
+ * that went away.
+ * @param[in] vptr User callback pointer to search for.
*/
void
delete_resolver_queries(const void *vptr)
struct dlink *ptr, *next_ptr;
struct reslist *request;
- for (ptr = request_list.next; ptr != &request_list; ptr = next_ptr)
- {
- next_ptr = ptr->next;
- request = (struct reslist*)ptr;
- if (vptr == request->query.vptr)
- rem_request(request);
+ if (request_list.next) {
+ for (ptr = request_list.next; ptr != &request_list; ptr = next_ptr)
+ {
+ next_ptr = ptr->next;
+ request = (struct reslist*)ptr;
+ if (vptr == request->query.vptr) {
+ Debug((DEBUG_DNS, "Removing request %p with vptr %p", request, vptr));
+ 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.
+/** Send a message to all of our nameservers.
+ * @param[in] msg Message to send.
+ * @param[in] len Length of message.
+ * @param[in] rcount Maximum number of servers to ask.
+ * @return Number of servers that were successfully asked.
*/
static int
send_res_msg(const char *msg, int len, int rcount)
max_queries = 1;
for (i = 0; i < max_queries; i++)
- {
- if (sendto(s_fd(&res_socket), msg, len, 0,
- (struct sockaddr*)&(irc_nsaddr_list[i]),
- irc_nsaddr_list[i].ss_len) == len)
+ if (os_sendto_nonb(s_fd(&res_socket), msg, len, NULL, 0, &irc_nsaddr_list[i]) == IO_SUCCESS)
++sent;
- }
return(sent);
}
-/*
- * find_id - find a dns request id (id is determined by dn_mkquery)
+/** Find a DNS request by ID.
+ * @param[in] id Identifier to find.
+ * @return Matching DNS request, or NULL if none are found.
*/
static struct reslist *
find_id(int id)
{
request = (struct reslist*)ptr;
- if (request->id == id)
+ if (request->id == id) {
+ Debug((DEBUG_DNS, "find_id(%d) -> %p", id, request));
return(request);
+ }
}
+ Debug((DEBUG_DNS, "find_id(%d) -> NULL", id));
return(NULL);
}
-/*
- * gethost_byname_type - get host address from name
- *
- */
-void
-gethost_byname_type(const char *name, const struct DNSQuery *query, int type)
-{
- assert(name != 0);
- do_query_name(query, name, NULL, type);
-}
-
-/*
- * gethost_byname - wrapper for _type - send T_AAAA first
+/** Try to look up address for a hostname, trying IPv6 (T_AAAA) first.
+ * @param[in] name Hostname to look up.
+ * @param[in] query Callback information.
*/
void
gethost_byname(const char *name, const struct DNSQuery *query)
{
- gethost_byname_type(name, query, T_AAAA);
+ do_query_name(query, name, NULL, T_AAAA);
}
-/*
- * gethost_byaddr - get host name from address
+/** Try to look up hostname for an address.
+ * @param[in] addr Address to look up.
+ * @param[in] query Callback information.
*/
void
-gethost_byaddr(const struct irc_ssaddr *addr, const struct DNSQuery *query)
+gethost_byaddr(const struct irc_in_addr *addr, const struct DNSQuery *query)
{
do_query_number(query, addr, NULL);
}
-/*
- * gethost_byinaddr - kludgy hack for IPv4-only compatibility
- */
-void
-gethost_byinaddr(const struct in_addr *addr, const struct DNSQuery *query)
-{
- struct irc_ssaddr new_addr;
- struct sockaddr_in *sin;
- memset(&new_addr, 0, sizeof(new_addr));
- sin = (struct sockaddr_in*)&new_addr.ss;
- sin->sin_family = AF_INET;
- memcpy(&sin->sin_addr, addr, sizeof(sin->sin_addr));
- new_addr.ss_len = sizeof(*sin);
- gethost_byaddr(&new_addr, query);
-}
-
-/*
- * do_query_name - nameserver lookup name
+/** Send a query to look up the address for a name.
+ * @param[in] query Callback information.
+ * @param[in] name Hostname to look up.
+ * @param[in] request DNS lookup structure (may be NULL).
+ * @param[in] type Preferred request type.
*/
static void
do_query_name(const struct DNSQuery *query, const char *name,
if (request == NULL)
{
request = make_request(query);
- request->name = (char *)MyMalloc(strlen(host_name) + 1);
- request->type = type;
- strcpy(request->name, host_name);
+ DupString(request->name, host_name);
#ifdef IPV6
if (type != T_A)
request->state = REQ_AAAA;
}
request->type = type;
+ Debug((DEBUG_DNS, "Requesting DNS %s %s as %p", (request->state == REQ_AAAA ? "AAAA" : "A"), host_name, request));
query_name(host_name, C_IN, type, request);
}
-/*
- * do_query_number - Use this to do reverse IP# lookups.
+/** Send a query to look up the name for an address.
+ * @param[in] query Callback information.
+ * @param[in] addr Address to look up.
+ * @param[in] request DNS lookup structure (may be NULL).
*/
static void
-do_query_number(const struct DNSQuery *query, const struct irc_ssaddr *addr,
+do_query_number(const struct DNSQuery *query, const struct irc_in_addr *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;
- ircd_snprintf(NULL, ipbuf, sizeof(ipbuf),
- "%u.%u.%u.%u.in-addr.arpa.",
+ if (irc_in_addr_is_ipv4(addr))
+ {
+ cp = (const unsigned char*)&addr->in6_16[6];
+ ircd_snprintf(NULL, ipbuf, sizeof(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)
+ else
{
- struct sockaddr_in6 *v6 = (struct sockaddr_in6 *)addr;
- cp = (const unsigned char *)&v6->sin6_addr.s6_addr;
+ const char *intarpa;
if (request != NULL && request->state == REQ_INT)
intarpa = "int";
else
intarpa = "arpa";
+ cp = (const unsigned char *)&addr->in6_16[0];
ircd_snprintf(NULL, ipbuf, sizeof(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[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));
+ memcpy(&request->addr, addr, sizeof(request->addr));
request->name = (char *)MyMalloc(HOSTLEN + 1);
}
-
+ Debug((DEBUG_DNS, "Requesting DNS PTR %s as %p", ipbuf, request));
query_name(ipbuf, C_IN, T_PTR, request);
}
-/*
- * query_name - generate a query based on class, type and name.
+/** Generate a query based on class, type and name.
+ * @param[in] name Domain name to look up.
+ * @param[in] query_class Query class (see RFC 1035).
+ * @param[in] type Query type (see RFC 1035).
+ * @param[in] request DNS request structure.
*/
static void
query_name(const char *name, int query_class, int type,
memset(buf, 0, sizeof(buf));
- if ((request_len = irc_res_mkquery(name, query_class, type,
+ if ((request_len = irc_res_mkquery(name, query_class, type,
(unsigned char *)buf, sizeof(buf))) > 0)
{
HEADER *header = (HEADER *)buf;
-#ifndef 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 LRAND48
do
{
- header->id = (header->id + lrand48()) & 0xffff;
+ header->id = (header->id + ircrandom()) & 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 /* LRAND48 */
request->id = header->id;
++request->sends;
request->sent += send_res_msg(buf, request_len, request->sends);
+ check_resolver_timeout(request->sentat + request->timeout);
}
}
+/** Send a failed DNS lookup request again.
+ * @param[in] request Request to resend.
+ */
static void
resend_query(struct reslist *request)
{
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
+/** Process the answer for a lookup request.
+ * @param[in] request DNS request that got an answer.
+ * @param[in] header Header of DNS response.
+ * @param[in] buf DNS response body.
+ * @param[in] eob Pointer to end of DNS response.
+ * @return Number of answers read from \a buf.
*/
static int
proc_answer(struct reslist *request, HEADER* header, char* buf, char* eob)
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)
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
+ /*
+ * Wait to set request->type until we verify this structure
*/
switch (type)
{
*/
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));
+ memset(&request->addr, 0, sizeof(request->addr));
+ memcpy(&request->addr.in6_16[6], 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))
+ if (rd_length != sizeof(struct irc_in_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));
+ memcpy(&request->addr, current, sizeof(struct irc_in_addr));
return(1);
break;
-#endif
case T_PTR:
if (request->type != T_PTR)
return(0);
return(1);
break;
- case T_CNAME: /* first check we already havent started looking
+ case T_CNAME: /* first check we already havent started looking
into a cname */
- if (request->type != T_PTR)
+ if (request->type != T_PTR)
return(0);
if (request->state == REQ_CNAME)
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
return(1);
}
-/*
- * res_readreply - read a dns reply from the nameserver and process it.
+/** Read a DNS reply from the nameserver and process it.
+ * @param[in] ev I/O activity event for resolver socket.
*/
static void
res_readreply(struct Event *ev)
{
+ struct irc_sockaddr lsin;
struct Socket *sock;
char buf[sizeof(HEADER) + MAXPACKET];
HEADER *header;
struct reslist *request = NULL;
struct DNSReply *reply = NULL;
- int rc;
+ unsigned int rc;
int answer_count;
- socklen_t len = sizeof(struct irc_ssaddr);
- struct irc_ssaddr lsin;
assert(ev_socket(ev) == &res_socket);
sock = ev_socket(ev);
- rc = recvfrom(s_fd(sock), buf, sizeof(buf), 0, (struct sockaddr *)&lsin, &len);
- /* Better to cast the sizeof instead of rc */
- if (rc <= (int)(sizeof(HEADER)))
+ if (IO_SUCCESS != os_recvfrom_nonb(s_fd(sock), buf, sizeof(buf), &rc, &lsin)
+ || (rc <= sizeof(HEADER)))
return;
/*
resend_query(request);
else
{
- /*
+ /*
* 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;
+ request->timeout += feature_int(FEAT_IRCD_RES_TIMEOUT);
resend_query(request);
}
else if (request->type == T_PTR && request->state != REQ_INT &&
- request->addr.ss.ss_family == AF_INET6)
+ !irc_in_addr_is_ipv4(&request->addr))
{
request->state = REQ_INT;
- request->timeout += 4;
+ request->timeout += feature_int(FEAT_IRCD_RES_TIMEOUT);
resend_query(request);
}
else
-#endif
{
/*
* If a bad error was returned, we stop here and dont send
* send any more (no retries granted).
*/
+ Debug((DEBUG_DNS, "Request %p has bad response (state %d type %d)", request, request->state, request->type));
(*request->query.callback)(request->query.vptr, 0);
rem_request(request);
- }
+ }
}
return;
}
/*
- * If this fails there was an error decoding the received packet,
+ * 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);
* got a PTR response with no name, something bogus is happening
* don't bother trying again, the client address doesn't resolve
*/
+ Debug((DEBUG_DNS, "Request %p PTR had empty name", request));
(*request->query.callback)(request->query.vptr, reply);
rem_request(request);
return;
/*
* Lookup the 'authoritative' name that we were given for the
- * ip#.
- *
+ * ip#.
*/
#ifdef IPV6
- if (request->addr.ss.ss_family == AF_INET6)
- gethost_byname_type(request->name, &request->query, T_AAAA);
+ if (!irc_in_addr_is_ipv4(&request->addr))
+ do_query_name(&request->query, request->name, NULL, T_AAAA);
else
#endif
- gethost_byname_type(request->name, &request->query, T_A);
+ do_query_name(&request->query, request->name, NULL, T_A);
+ Debug((DEBUG_DNS, "Request %p switching to forward resolution", request));
rem_request(request);
}
else
*/
reply = make_dnsreply(request);
(*request->query.callback)(request->query.vptr, (reply) ? reply : 0);
+ Debug((DEBUG_DNS, "Request %p got forward resolution", request));
rem_request(request);
}
}
assert(0);
/* XXX don't leak it */
+ Debug((DEBUG_DNS, "Request %p was unexpected(!)", request));
rem_request(request);
}
}
+/** Build a DNSReply for a completed request.
+ * @param[in] request Completed DNS request.
+ * @return Newly allocated DNSReply containing host name and address.
+ */
static struct DNSReply *
make_dnsreply(struct reslist *request)
{
return(cp);
}
+/** Statistics callback to list DNS servers.
+ * @param[in] source_p Client requesting statistics.
+ * @param[in] sd Stats descriptor for request (ignored).
+ * @param[in] param Extra parameter from user (ignored).
+ */
void
-report_dns_servers(struct Client *source_p, struct StatDesc *sd, int stat, char *param)
+report_dns_servers(struct Client *source_p, const struct StatDesc *sd, char *param)
{
int i;
char ipaddr[128];
for (i = 0; i < irc_nscount; i++)
{
- irc_getnameinfo((struct sockaddr *)&(irc_nsaddr_list[i]),
- irc_nsaddr_list[i].ss_len, ipaddr, sizeof(ipaddr), NULL, 0,
- NI_NUMERICHOST);
- send_reply(source_p, RPL_STATSALINE, ipaddr);
+ ircd_ntoa_r(ipaddr, &irc_nsaddr_list[i].addr);
+ send_reply(source_p, RPL_STATSALINE, ipaddr);
}
}
+/** Report memory usage to a client.
+ * @param[in] sptr Client requesting information.
+ * @return Total memory used by pending requests.
+ */
size_t
cres_mem(struct Client* sptr)
{
size_t request_mem = 0;
int request_count = 0;
- for (dlink = request_list.next; dlink != &request_list; dlink = dlink->next) {
- request = (struct reslist*)dlink;
- request_mem += sizeof(*request);
- if (request->name)
- request_mem += strlen(request->name) + 1;
- ++request_count;
+ if (request_list.next) {
+ for (dlink = request_list.next; dlink != &request_list; dlink = dlink->next) {
+ request = (struct reslist*)dlink;
+ request_mem += sizeof(*request);
+ if (request->name)
+ request_mem += strlen(request->name) + 1;
+ ++request_count;
+ }
}
send_reply(sptr, SND_EXPLICIT | RPL_STATSDEBUG,
":Resolver: requests %d(%d)", request_count, request_mem);
return request_mem;
}
+
+/** Check whether an address looks valid.
+ * This means not all 0s and not all 1s.
+ * @param[in] addr Address to check for validity.
+ * @return Non-zero if the address looks valid.
+ */
+int irc_in_addr_valid(const struct irc_in_addr *addr)
+{
+ unsigned int ii;
+ unsigned short val;
+
+ val = addr->in6_16[0];
+ if (val != 0 && val != 0xffff)
+ return 1;
+ for (ii = 1; ii < 8; ii++)
+ if (addr->in6_16[ii] != val)
+ return 1;
+ return 0;
+}
+
+/** Compare two IP addresses.
+ * @param[in] a First address to compare.
+ * @param[in] b Second address to compare.
+ * @return Non-zero if the two addresses differ, zero if they are identical.
+ */
+int irc_in_addr_cmp(const struct irc_in_addr *a, const struct irc_in_addr *b)
+{
+ if (irc_in_addr_is_ipv4(a))
+ return a->in6_16[6] != b->in6_16[6]
+ || a->in6_16[7] != b->in6_16[7]
+ || !irc_in_addr_is_ipv4(b);
+ else
+ return memcmp(a, b, sizeof(*a));
+}
+
+/** Indicate whether an IP address is a loopback address.
+ * @param[in] addr Address to check.
+ * @return Non-zero if the address is loopback; zero if not.
+ */
+int irc_in_addr_is_loopback(const struct irc_in_addr *addr)
+{
+ if (addr->in6_16[0] != 0
+ || addr->in6_16[1] != 0
+ || addr->in6_16[2] != 0
+ || addr->in6_16[3] != 0
+ || addr->in6_16[4] != 0)
+ return 0;
+ if ((addr->in6_16[5] == 0xffff) || (addr->in6_16[5] == 0 && addr->in6_16[6] != 0))
+ return (ntohs(addr->in6_16[6]) & 0xff00) == 0x7f00;
+ else
+ return addr->in6_16[5] == 0 && addr->in6_16[6] == 0 && htons(addr->in6_16[7]) == 1;
+}
projects / ircu2.10.12-pk.git / blobdiff