+/* Copyright (C) 2016-2019 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
/*
* Copyright (c) 1985, 1989, 1993
* The Regents of the University of California. All rights reserved.
* SOFTWARE.
*/
-#if defined(LIBC_SCCS) && !defined(lint)
-static const char sccsid[] = "@(#)res_send.c 8.1 (Berkeley) 6/4/93";
-static const char rcsid[] = "$BINDId: res_send.c,v 8.38 2000/03/30 20:16:51 vixie Exp $";
-#endif /* LIBC_SCCS and not lint */
-
/*
* Send query to name server and wait for reply.
*/
#include <errno.h>
#include <fcntl.h>
#include <netdb.h>
-#include <resolv.h>
+#include <resolv/resolv-internal.h>
+#include <resolv/resolv_context.h>
#include <signal.h>
-#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <kernel-features.h>
-#include <libc-internal.h>
+#include <libc-diag.h>
+#include <random-bits.h>
#if PACKETSZ > 65536
#define MAXPACKET PACKETSZ
#define MAXPACKET 65536
#endif
-
-#ifndef __ASSUME_SOCK_CLOEXEC
-static int __have_o_nonblock;
-#else
-# define __have_o_nonblock 0
-#endif
-
-
/* From ev_streams.c. */
static inline void
}
-/* Options. Leave them on. */
-/* #undef DEBUG */
-#include "res_debug.h"
-
#define EXT(res) ((res)->_u._ext)
/* Forward. */
+static struct sockaddr *get_nsaddr (res_state, unsigned int);
static int send_vc(res_state, const u_char *, int,
const u_char *, int,
u_char **, int *, int *, int, u_char **,
u_char **, int *, int *, int,
int *, int *, u_char **,
u_char **, int *, int *, int *);
-#ifdef DEBUG
-static void Aerror(const res_state, FILE *, const char *, int,
- const struct sockaddr *);
-static void Perror(const res_state, FILE *, const char *, int);
-#endif
static int sock_eq(struct sockaddr_in6 *, struct sockaddr_in6 *);
/* Public. */
in_port_t port = in4p->sin_port;
in_addr_t addr = in4p->sin_addr.s_addr;
- for (ns = 0; ns < MAXNS; ns++) {
+ for (ns = 0; ns < statp->nscount; ns++) {
const struct sockaddr_in *srv =
- (struct sockaddr_in *)EXT(statp).nsaddrs[ns];
+ (struct sockaddr_in *) get_nsaddr (statp, ns);
- if ((srv != NULL) && (srv->sin_family == AF_INET) &&
+ if ((srv->sin_family == AF_INET) &&
(srv->sin_port == port) &&
(srv->sin_addr.s_addr == INADDR_ANY ||
srv->sin_addr.s_addr == addr))
return (1);
}
} else if (inp->sin6_family == AF_INET6) {
- for (ns = 0; ns < MAXNS; ns++) {
- const struct sockaddr_in6 *srv = EXT(statp).nsaddrs[ns];
- if ((srv != NULL) && (srv->sin6_family == AF_INET6) &&
+ for (ns = 0; ns < statp->nscount; ns++) {
+ const struct sockaddr_in6 *srv
+ = (struct sockaddr_in6 *) get_nsaddr (statp, ns);
+ if ((srv->sin6_family == AF_INET6) &&
(srv->sin6_port == inp->sin6_port) &&
!(memcmp(&srv->sin6_addr, &in6addr_any,
sizeof (struct in6_addr)) &&
return (0);
}
+int
+res_isourserver (const struct sockaddr_in *inp)
+{
+ return res_ourserver_p (&_res, (const struct sockaddr_in6 *) inp);
+}
+
/* int
* res_nameinquery(name, type, class, buf, eom)
* look for (name,type,class) in the query section of packet (buf,eom)
}
libresolv_hidden_def (res_nameinquery)
+/* Returns a shift value for the name server index. Used to implement
+ RES_ROTATE. */
+static unsigned int
+nameserver_offset (struct __res_state *statp)
+{
+ /* If we only have one name server or rotation is disabled, return
+ offset 0 (no rotation). */
+ unsigned int nscount = statp->nscount;
+ if (nscount <= 1 || !(statp->options & RES_ROTATE))
+ return 0;
+
+ /* Global offset. The lowest bit indicates whether the offset has
+ been initialized with a random value. Use relaxed MO to access
+ global_offset because all we need is a sequence of roughly
+ sequential value. */
+ static unsigned int global_offset;
+ unsigned int offset = atomic_fetch_add_relaxed (&global_offset, 2);
+ if ((offset & 1) == 0)
+ {
+ /* Initialization is required. */
+ offset = random_bits ();
+ /* The lowest bit is the most random. Preserve it. */
+ offset <<= 1;
+
+ /* Store the new starting value. atomic_fetch_add_relaxed
+ returns the old value, so emulate that by storing the new
+ (incremented) value. Concurrent initialization with
+ different random values is harmless. */
+ atomic_store_relaxed (&global_offset, (offset | 1) + 2);
+ }
+
+ /* Remove the initialization bit. */
+ offset >>= 1;
+
+ /* Avoid the division in the most common cases. */
+ switch (nscount)
+ {
+ case 2:
+ return offset & 1;
+ case 3:
+ return offset % 3;
+ case 4:
+ return offset & 3;
+ default:
+ return offset % nscount;
+ }
+}
+
/* int
* res_queriesmatch(buf1, eom1, buf2, eom2)
* is there a 1:1 mapping of (name,type,class)
libresolv_hidden_def (res_queriesmatch)
int
-__libc_res_nsend(res_state statp, const u_char *buf, int buflen,
- const u_char *buf2, int buflen2,
- u_char *ans, int anssiz, u_char **ansp, u_char **ansp2,
- int *nansp2, int *resplen2, int *ansp2_malloced)
+__res_context_send (struct resolv_context *ctx,
+ const unsigned char *buf, int buflen,
+ const unsigned char *buf2, int buflen2,
+ unsigned char *ans, int anssiz,
+ unsigned char **ansp, unsigned char **ansp2,
+ int *nansp2, int *resplen2, int *ansp2_malloced)
{
- int gotsomewhere, terrno, try, v_circuit, resplen, ns, n;
+ struct __res_state *statp = ctx->resp;
+ int gotsomewhere, terrno, try, v_circuit, resplen, n;
if (statp->nscount == 0) {
__set_errno (ESRCH);
return (-1);
}
-#ifdef USE_HOOKS
- if (__glibc_unlikely (statp->qhook || statp->rhook)) {
- if (anssiz < MAXPACKET && ansp) {
- u_char *buf = malloc (MAXPACKET);
- if (buf == NULL)
- return (-1);
- memcpy (buf, ans, HFIXEDSZ);
- *ansp = buf;
- ans = buf;
- anssiz = MAXPACKET;
- }
- }
-#endif
-
- DprintQ((statp->options & RES_DEBUG) || (statp->pfcode & RES_PRF_QUERY),
- (stdout, ";; res_send()\n"), buf, buflen);
v_circuit = ((statp->options & RES_USEVC)
|| buflen > PACKETSZ
|| buflen2 > PACKETSZ);
* If the ns_addr_list in the resolver context has changed, then
* invalidate our cached copy and the associated timing data.
*/
- if (EXT(statp).nsinit) {
+ if (EXT(statp).nscount != 0) {
int needclose = 0;
if (EXT(statp).nscount != statp->nscount)
needclose++;
else
- for (ns = 0; ns < MAXNS; ns++) {
- unsigned int map = EXT(statp).nsmap[ns];
- if (map < MAXNS
+ for (unsigned int ns = 0; ns < statp->nscount; ns++) {
+ if (statp->nsaddr_list[ns].sin_family != 0
&& !sock_eq((struct sockaddr_in6 *)
- &statp->nsaddr_list[map],
+ &statp->nsaddr_list[ns],
EXT(statp).nsaddrs[ns]))
{
needclose++;
break;
}
}
- if (needclose)
+ if (needclose) {
__res_iclose(statp, false);
+ EXT(statp).nscount = 0;
+ }
}
/*
* Maybe initialize our private copy of the ns_addr_list.
*/
- if (EXT(statp).nsinit == 0) {
- unsigned char map[MAXNS];
-
- memset (map, MAXNS, sizeof (map));
- for (n = 0; n < MAXNS; n++) {
- ns = EXT(statp).nsmap[n];
- if (ns < statp->nscount)
- map[ns] = n;
- else if (ns < MAXNS) {
- free(EXT(statp).nsaddrs[n]);
- EXT(statp).nsaddrs[n] = NULL;
- EXT(statp).nsmap[n] = MAXNS;
- }
- }
- n = statp->nscount;
- if (statp->nscount > EXT(statp).nscount)
- for (n = EXT(statp).nscount, ns = 0;
- n < statp->nscount; n++) {
- while (ns < MAXNS
- && EXT(statp).nsmap[ns] != MAXNS)
- ns++;
- if (ns == MAXNS)
- break;
- /* NS never exceeds MAXNS, but gcc 4.9 somehow
- does not see this. */
- DIAG_PUSH_NEEDS_COMMENT;
- DIAG_IGNORE_NEEDS_COMMENT (4.9,
- "-Warray-bounds");
- EXT(statp).nsmap[ns] = n;
- DIAG_POP_NEEDS_COMMENT;
- map[n] = ns++;
- }
- EXT(statp).nscount = n;
- for (ns = 0; ns < EXT(statp).nscount; ns++) {
- n = map[ns];
- if (EXT(statp).nsaddrs[n] == NULL)
- EXT(statp).nsaddrs[n] =
+ if (EXT(statp).nscount == 0) {
+ for (unsigned int ns = 0; ns < statp->nscount; ns++) {
+ EXT(statp).nssocks[ns] = -1;
+ if (statp->nsaddr_list[ns].sin_family == 0)
+ continue;
+ if (EXT(statp).nsaddrs[ns] == NULL)
+ EXT(statp).nsaddrs[ns] =
malloc(sizeof (struct sockaddr_in6));
- if (EXT(statp).nsaddrs[n] != NULL) {
- memset (mempcpy(EXT(statp).nsaddrs[n],
+ if (EXT(statp).nsaddrs[ns] != NULL)
+ memset (mempcpy(EXT(statp).nsaddrs[ns],
&statp->nsaddr_list[ns],
sizeof (struct sockaddr_in)),
'\0',
sizeof (struct sockaddr_in6)
- sizeof (struct sockaddr_in));
- EXT(statp).nssocks[n] = -1;
- n++;
- }
+ else
+ return -1;
}
- EXT(statp).nsinit = 1;
+ EXT(statp).nscount = statp->nscount;
}
- /*
- * Some resolvers want to even out the load on their nameservers.
- * Note that RES_BLAST overrides RES_ROTATE.
- */
- if (__builtin_expect ((statp->options & RES_ROTATE) != 0, 0) &&
- (statp->options & RES_BLAST) == 0) {
- struct sockaddr_in6 *ina;
- unsigned int map;
-
- n = 0;
- while (n < MAXNS && EXT(statp).nsmap[n] == MAXNS)
- n++;
- if (n < MAXNS) {
- ina = EXT(statp).nsaddrs[n];
- map = EXT(statp).nsmap[n];
- for (;;) {
- ns = n + 1;
- while (ns < MAXNS
- && EXT(statp).nsmap[ns] == MAXNS)
- ns++;
- if (ns == MAXNS)
- break;
- EXT(statp).nsaddrs[n] = EXT(statp).nsaddrs[ns];
- EXT(statp).nsmap[n] = EXT(statp).nsmap[ns];
- n = ns;
- }
- EXT(statp).nsaddrs[n] = ina;
- EXT(statp).nsmap[n] = map;
- }
- }
+ /* Name server index offset. Used to implement
+ RES_ROTATE. */
+ unsigned int ns_offset = nameserver_offset (statp);
/*
* Send request, RETRY times, or until successful.
*/
for (try = 0; try < statp->retry; try++) {
- for (ns = 0; ns < MAXNS; ns++)
+ for (unsigned ns_shift = 0; ns_shift < statp->nscount; ns_shift++)
{
-#ifdef DEBUG
- char tmpbuf[40];
-#endif
- struct sockaddr_in6 *nsap = EXT(statp).nsaddrs[ns];
+ /* The actual name server index. This implements
+ RES_ROTATE. */
+ unsigned int ns = ns_shift + ns_offset;
+ if (ns >= statp->nscount)
+ ns -= statp->nscount;
- if (nsap == NULL)
- goto next_ns;
same_ns:
-#ifdef USE_HOOKS
- if (__glibc_unlikely (statp->qhook != NULL)) {
- int done = 0, loops = 0;
-
- do {
- res_sendhookact act;
-
- struct sockaddr_in *nsap4;
- nsap4 = (struct sockaddr_in *) nsap;
- act = (*statp->qhook)(&nsap4, &buf, &buflen,
- ans, anssiz, &resplen);
- nsap = (struct sockaddr_in6 *) nsap4;
- switch (act) {
- case res_goahead:
- done = 1;
- break;
- case res_nextns:
- __res_iclose(statp, false);
- goto next_ns;
- case res_done:
- return (resplen);
- case res_modified:
- /* give the hook another try */
- if (++loops < 42) /*doug adams*/
- break;
- /*FALLTHROUGH*/
- case res_error:
- /*FALLTHROUGH*/
- default:
- return (-1);
- }
- } while (!done);
- }
-#endif
-
- Dprint(statp->options & RES_DEBUG,
- (stdout, ";; Querying server (# %d) address = %s\n",
- ns + 1, inet_ntop(nsap->sin6_family,
- (nsap->sin6_family == AF_INET6
- ? &nsap->sin6_addr
- : &((struct sockaddr_in *) nsap)->sin_addr),
- tmpbuf, sizeof (tmpbuf))));
-
if (__glibc_unlikely (v_circuit)) {
/* Use VC; at most one attempt per server. */
try = statp->retry;
resplen = n;
- Dprint((statp->options & RES_DEBUG) ||
- ((statp->pfcode & RES_PRF_REPLY) &&
- (statp->pfcode & RES_PRF_HEAD1)),
- (stdout, ";; got answer:\n"));
-
- DprintQ((statp->options & RES_DEBUG) ||
- (statp->pfcode & RES_PRF_REPLY),
- (stdout, "%s", ""),
- ans, (resplen > anssiz) ? anssiz : resplen);
- if (buf2 != NULL) {
- DprintQ((statp->options & RES_DEBUG) ||
- (statp->pfcode & RES_PRF_REPLY),
- (stdout, "%s", ""),
- *ansp2, (*resplen2 > *nansp2) ? *nansp2 : *resplen2);
- }
-
/*
* If we have temporarily opened a virtual circuit,
* or if we haven't been asked to keep a socket open,
(statp->options & RES_STAYOPEN) == 0) {
__res_iclose(statp, false);
}
-#ifdef USE_HOOKS
- if (__glibc_unlikely (statp->rhook)) {
- int done = 0, loops = 0;
-
- do {
- res_sendhookact act;
-
- act = (*statp->rhook)((struct sockaddr_in *)
- nsap, buf, buflen,
- ans, anssiz, &resplen);
- switch (act) {
- case res_goahead:
- case res_done:
- done = 1;
- break;
- case res_nextns:
- __res_iclose(statp, false);
- goto next_ns;
- case res_modified:
- /* give the hook another try */
- if (++loops < 42) /*doug adams*/
- break;
- /*FALLTHROUGH*/
- case res_error:
- /*FALLTHROUGH*/
- default:
- return (-1);
- }
- } while (!done);
-
- }
-#endif
return (resplen);
next_ns: ;
} /*foreach ns*/
return (-1);
}
+/* Common part of res_nsend and res_send. */
+static int
+context_send_common (struct resolv_context *ctx,
+ const unsigned char *buf, int buflen,
+ unsigned char *ans, int anssiz)
+{
+ if (ctx == NULL)
+ {
+ RES_SET_H_ERRNO (&_res, NETDB_INTERNAL);
+ return -1;
+ }
+ int result = __res_context_send (ctx, buf, buflen, NULL, 0, ans, anssiz,
+ NULL, NULL, NULL, NULL, NULL);
+ __resolv_context_put (ctx);
+ return result;
+}
+
int
-res_nsend(res_state statp,
- const u_char *buf, int buflen, u_char *ans, int anssiz)
+res_nsend (res_state statp, const unsigned char *buf, int buflen,
+ unsigned char *ans, int anssiz)
{
- return __libc_res_nsend(statp, buf, buflen, NULL, 0, ans, anssiz,
- NULL, NULL, NULL, NULL, NULL);
+ return context_send_common
+ (__resolv_context_get_override (statp), buf, buflen, ans, anssiz);
+}
+
+int
+res_send (const unsigned char *buf, int buflen, unsigned char *ans, int anssiz)
+{
+ return context_send_common
+ (__resolv_context_get (), buf, buflen, ans, anssiz);
}
-libresolv_hidden_def (res_nsend)
/* Private */
+static struct sockaddr *
+get_nsaddr (res_state statp, unsigned int n)
+{
+ assert (n < statp->nscount);
+
+ if (statp->nsaddr_list[n].sin_family == 0 && EXT(statp).nsaddrs[n] != NULL)
+ /* EXT(statp).nsaddrs[n] holds an address that is larger than
+ struct sockaddr, and user code did not update
+ statp->nsaddr_list[n]. */
+ return (struct sockaddr *) EXT(statp).nsaddrs[n];
+ else
+ /* User code updated statp->nsaddr_list[n], or statp->nsaddr_list[n]
+ has the same content as EXT(statp).nsaddrs[n]. */
+ return (struct sockaddr *) (void *) &statp->nsaddr_list[n];
+}
+
+/* Close the resolver structure, assign zero to *RESPLEN2 if RESPLEN2
+ is not NULL, and return zero. */
+static int
+__attribute__ ((warn_unused_result))
+close_and_return_error (res_state statp, int *resplen2)
+{
+ __res_iclose(statp, false);
+ if (resplen2 != NULL)
+ *resplen2 = 0;
+ return 0;
+}
+
+/* The send_vc function is responsible for sending a DNS query over TCP
+ to the nameserver numbered NS from the res_state STATP i.e.
+ EXT(statp).nssocks[ns]. The function supports sending both IPv4 and
+ IPv6 queries at the same serially on the same socket.
+
+ Please note that for TCP there is no way to disable sending both
+ queries, unlike UDP, which honours RES_SNGLKUP and RES_SNGLKUPREOP
+ and sends the queries serially and waits for the result after each
+ sent query. This implementation should be corrected to honour these
+ options.
+
+ Please also note that for TCP we send both queries over the same
+ socket one after another. This technically violates best practice
+ since the server is allowed to read the first query, respond, and
+ then close the socket (to service another client). If the server
+ does this, then the remaining second query in the socket data buffer
+ will cause the server to send the client an RST which will arrive
+ asynchronously and the client's OS will likely tear down the socket
+ receive buffer resulting in a potentially short read and lost
+ response data. This will force the client to retry the query again,
+ and this process may repeat until all servers and connection resets
+ are exhausted and then the query will fail. It's not known if this
+ happens with any frequency in real DNS server implementations. This
+ implementation should be corrected to use two sockets by default for
+ parallel queries.
+
+ The query stored in BUF of BUFLEN length is sent first followed by
+ the query stored in BUF2 of BUFLEN2 length. Queries are sent
+ serially on the same socket.
+
+ Answers to the query are stored firstly in *ANSP up to a max of
+ *ANSSIZP bytes. If more than *ANSSIZP bytes are needed and ANSCP
+ is non-NULL (to indicate that modifying the answer buffer is allowed)
+ then malloc is used to allocate a new response buffer and ANSCP and
+ ANSP will both point to the new buffer. If more than *ANSSIZP bytes
+ are needed but ANSCP is NULL, then as much of the response as
+ possible is read into the buffer, but the results will be truncated.
+ When truncation happens because of a small answer buffer the DNS
+ packets header field TC will bet set to 1, indicating a truncated
+ message and the rest of the socket data will be read and discarded.
+
+ Answers to the query are stored secondly in *ANSP2 up to a max of
+ *ANSSIZP2 bytes, with the actual response length stored in
+ *RESPLEN2. If more than *ANSSIZP bytes are needed and ANSP2
+ is non-NULL (required for a second query) then malloc is used to
+ allocate a new response buffer, *ANSSIZP2 is set to the new buffer
+ size and *ANSP2_MALLOCED is set to 1.
+
+ The ANSP2_MALLOCED argument will eventually be removed as the
+ change in buffer pointer can be used to detect the buffer has
+ changed and that the caller should use free on the new buffer.
+
+ Note that the answers may arrive in any order from the server and
+ therefore the first and second answer buffers may not correspond to
+ the first and second queries.
+
+ It is not supported to call this function with a non-NULL ANSP2
+ but a NULL ANSCP. Put another way, you can call send_vc with a
+ single unmodifiable buffer or two modifiable buffers, but no other
+ combination is supported.
+
+ It is the caller's responsibility to free the malloc allocated
+ buffers by detecting that the pointers have changed from their
+ original values i.e. *ANSCP or *ANSP2 has changed.
+
+ If errors are encountered then *TERRNO is set to an appropriate
+ errno value and a zero result is returned for a recoverable error,
+ and a less-than zero result is returned for a non-recoverable error.
+
+ If no errors are encountered then *TERRNO is left unmodified and
+ a the length of the first response in bytes is returned. */
static int
send_vc(res_state statp,
const u_char *buf, int buflen, const u_char *buf2, int buflen2,
{
const HEADER *hp = (HEADER *) buf;
const HEADER *hp2 = (HEADER *) buf2;
- u_char *ans = *ansp;
- int orig_anssizp = *anssizp;
- // XXX REMOVE
- // int anssiz = *anssizp;
- HEADER *anhp = (HEADER *) ans;
- struct sockaddr_in6 *nsap = EXT(statp).nsaddrs[ns];
+ HEADER *anhp = (HEADER *) *ansp;
+ struct sockaddr *nsap = get_nsaddr (statp, ns);
int truncating, connreset, n;
/* On some architectures compiler might emit a warning indicating
'resplen' may be used uninitialized. However if buf2 == NULL
times round the loop resplen has been initialized. So this is
a false-positive.
*/
-#if __GNUC_PREREQ (4, 7)
DIAG_PUSH_NEEDS_COMMENT;
DIAG_IGNORE_NEEDS_COMMENT (5, "-Wmaybe-uninitialized");
-#endif
int resplen;
-#if __GNUC_PREREQ (4, 7)
DIAG_POP_NEEDS_COMMENT;
-#endif
struct iovec iov[4];
u_short len;
u_short len2;
u_char *cp;
- if (resplen2 != NULL)
- *resplen2 = 0;
connreset = 0;
same_ns:
truncating = 0;
if (getpeername(statp->_vcsock,
(struct sockaddr *)&peer, &size) < 0 ||
- !sock_eq(&peer, nsap)) {
- __res_iclose(statp, false);
+ !sock_eq(&peer, (struct sockaddr_in6 *) nsap)) {
+ __res_iclose(statp, false);
statp->_flags &= ~RES_F_VC;
}
}
if (statp->_vcsock >= 0)
__res_iclose(statp, false);
- statp->_vcsock = socket(nsap->sin6_family, SOCK_STREAM, 0);
+ statp->_vcsock = socket
+ (nsap->sa_family, SOCK_STREAM | SOCK_CLOEXEC, 0);
if (statp->_vcsock < 0) {
*terrno = errno;
- Perror(statp, stderr, "socket(vc)", errno);
+ if (resplen2 != NULL)
+ *resplen2 = 0;
return (-1);
}
__set_errno (0);
- if (connect(statp->_vcsock, (struct sockaddr *)nsap,
- nsap->sin6_family == AF_INET
+ if (connect(statp->_vcsock, nsap,
+ nsap->sa_family == AF_INET
? sizeof (struct sockaddr_in)
: sizeof (struct sockaddr_in6)) < 0) {
*terrno = errno;
- Aerror(statp, stderr, "connect/vc", errno,
- (struct sockaddr *) nsap);
- __res_iclose(statp, false);
- return (0);
+ return close_and_return_error (statp, resplen2);
}
statp->_flags |= RES_F_VC;
}
}
if (TEMP_FAILURE_RETRY (writev(statp->_vcsock, iov, niov)) != explen) {
*terrno = errno;
- Perror(statp, stderr, "write failed", errno);
- __res_iclose(statp, false);
- return (0);
+ return close_and_return_error (statp, resplen2);
}
/*
* Receive length & response
*/
int recvresp1 = 0;
+ /* Skip the second response if there is no second query.
+ To do that we mark the second response as received. */
int recvresp2 = buf2 == NULL;
uint16_t rlen16;
read_len:
}
if (n <= 0) {
*terrno = errno;
- Perror(statp, stderr, "read failed", errno);
- __res_iclose(statp, false);
/*
* A long running process might get its TCP
* connection reset if the remote server was
* instead of failing. We only allow one reset
* per query to prevent looping.
*/
- if (*terrno == ECONNRESET && !connreset) {
- connreset = 1;
- goto same_ns;
- }
- return (0);
+ if (*terrno == ECONNRESET && !connreset)
+ {
+ __res_iclose (statp, false);
+ connreset = 1;
+ goto same_ns;
+ }
+ return close_and_return_error (statp, resplen2);
}
int rlen = ntohs (rlen16);
u_char **thisansp;
int *thisresplenp;
if ((recvresp1 | recvresp2) == 0 || buf2 == NULL) {
+ /* We have not received any responses
+ yet or we only have one response to
+ receive. */
thisanssizp = anssizp;
thisansp = anscp ?: ansp;
assert (anscp != NULL || ansp2 == NULL);
thisresplenp = &resplen;
} else {
- if (*anssizp != MAXPACKET) {
- /* No buffer allocated for the first
- reply. We can try to use the rest
- of the user-provided buffer. */
-#if __GNUC_PREREQ (4, 7)
- DIAG_PUSH_NEEDS_COMMENT;
- DIAG_IGNORE_NEEDS_COMMENT (5, "-Wmaybe-uninitialized");
-#endif
-#if _STRING_ARCH_unaligned
- *anssizp2 = orig_anssizp - resplen;
- *ansp2 = *ansp + resplen;
-#else
- int aligned_resplen
- = ((resplen + __alignof__ (HEADER) - 1)
- & ~(__alignof__ (HEADER) - 1));
- *anssizp2 = orig_anssizp - aligned_resplen;
- *ansp2 = *ansp + aligned_resplen;
-#endif
-#if __GNUC_PREREQ (4, 7)
- DIAG_POP_NEEDS_COMMENT;
-#endif
- } else {
- /* The first reply did not fit into the
- user-provided buffer. Maybe the second
- answer will. */
- *anssizp2 = orig_anssizp;
- *ansp2 = *ansp;
- }
-
thisanssizp = anssizp2;
thisansp = ansp2;
thisresplenp = resplen2;
anhp = (HEADER *) *thisansp;
*thisresplenp = rlen;
- if (rlen > *thisanssizp) {
- /* Yes, we test ANSCP here. If we have two buffers
- both will be allocatable. */
- if (__glibc_likely (anscp != NULL)) {
+ /* Is the answer buffer too small? */
+ if (*thisanssizp < rlen) {
+ /* If the current buffer is not the the static
+ user-supplied buffer then we can reallocate
+ it. */
+ if (thisansp != NULL && thisansp != ansp) {
+ /* Always allocate MAXPACKET, callers expect
+ this specific size. */
u_char *newp = malloc (MAXPACKET);
- if (newp == NULL) {
- *terrno = ENOMEM;
- __res_iclose(statp, false);
- return (0);
- }
+ if (newp == NULL)
+ {
+ *terrno = ENOMEM;
+ return close_and_return_error (statp, resplen2);
+ }
*thisanssizp = MAXPACKET;
*thisansp = newp;
if (thisansp == ansp2)
*ansp2_malloced = 1;
anhp = (HEADER *) newp;
+ /* A uint16_t can't be larger than MAXPACKET
+ thus it's safe to allocate MAXPACKET but
+ read RLEN bytes instead. */
len = rlen;
} else {
- Dprint(statp->options & RES_DEBUG,
- (stdout, ";; response truncated\n")
- );
truncating = 1;
len = *thisanssizp;
}
/*
* Undersized message.
*/
- Dprint(statp->options & RES_DEBUG,
- (stdout, ";; undersized: %d\n", len));
*terrno = EMSGSIZE;
- __res_iclose(statp, false);
- return (0);
+ return close_and_return_error (statp, resplen2);
}
cp = *thisansp;
}
if (__glibc_unlikely (n <= 0)) {
*terrno = errno;
- Perror(statp, stderr, "read(vc)", errno);
- __res_iclose(statp, false);
- return (0);
+ return close_and_return_error (statp, resplen2);
}
if (__glibc_unlikely (truncating)) {
/*
* wait for the correct one.
*/
if ((recvresp1 || hp->id != anhp->id)
- && (recvresp2 || hp2->id != anhp->id)) {
- DprintQ((statp->options & RES_DEBUG) ||
- (statp->pfcode & RES_PRF_REPLY),
- (stdout, ";; old answer (unexpected):\n"),
- *thisansp,
- (rlen > *thisanssizp) ? *thisanssizp: rlen);
+ && (recvresp2 || hp2->id != anhp->id))
goto read_len;
- }
/* Mark which reply we received. */
if (recvresp1 == 0 && hp->id == anhp->id)
reopen (res_state statp, int *terrno, int ns)
{
if (EXT(statp).nssocks[ns] == -1) {
- struct sockaddr *nsap
- = (struct sockaddr *) EXT(statp).nsaddrs[ns];
+ struct sockaddr *nsap = get_nsaddr (statp, ns);
socklen_t slen;
/* only try IPv6 if IPv6 NS and if not failed before */
if (nsap->sa_family == AF_INET6 && !statp->ipv6_unavail) {
- if (__glibc_likely (__have_o_nonblock >= 0)) {
- EXT(statp).nssocks[ns] =
- socket(PF_INET6, SOCK_DGRAM|SOCK_NONBLOCK,
- 0);
-#ifndef __ASSUME_SOCK_CLOEXEC
- if (__have_o_nonblock == 0)
- __have_o_nonblock
- = (EXT(statp).nssocks[ns] == -1
- && errno == EINVAL ? -1 : 1);
-#endif
- }
- if (__glibc_unlikely (__have_o_nonblock < 0))
- EXT(statp).nssocks[ns] =
- socket(PF_INET6, SOCK_DGRAM, 0);
+ EXT(statp).nssocks[ns] = socket
+ (PF_INET6,
+ SOCK_DGRAM | SOCK_NONBLOCK | SOCK_CLOEXEC, 0);
if (EXT(statp).nssocks[ns] < 0)
statp->ipv6_unavail = errno == EAFNOSUPPORT;
slen = sizeof (struct sockaddr_in6);
} else if (nsap->sa_family == AF_INET) {
- if (__glibc_likely (__have_o_nonblock >= 0)) {
- EXT(statp).nssocks[ns]
- = socket(PF_INET, SOCK_DGRAM|SOCK_NONBLOCK,
- 0);
-#ifndef __ASSUME_SOCK_CLOEXEC
- if (__have_o_nonblock == 0)
- __have_o_nonblock
- = (EXT(statp).nssocks[ns] == -1
- && errno == EINVAL ? -1 : 1);
-#endif
- }
- if (__glibc_unlikely (__have_o_nonblock < 0))
- EXT(statp).nssocks[ns]
- = socket(PF_INET, SOCK_DGRAM, 0);
+ EXT(statp).nssocks[ns] = socket
+ (PF_INET,
+ SOCK_DGRAM | SOCK_NONBLOCK | SOCK_CLOEXEC, 0);
slen = sizeof (struct sockaddr_in);
}
if (EXT(statp).nssocks[ns] < 0) {
*terrno = errno;
- Perror(statp, stderr, "socket(dg)", errno);
return (-1);
}
+ /* Enable full ICMP error reporting for this
+ socket. */
+ if (__res_enable_icmp (nsap->sa_family,
+ EXT (statp).nssocks[ns]) < 0)
+ {
+ int saved_errno = errno;
+ __res_iclose (statp, false);
+ __set_errno (saved_errno);
+ *terrno = saved_errno;
+ return -1;
+ }
+
/*
* On a 4.3BSD+ machine (client and server,
* actually), sending to a nameserver datagram
* error message is received. We can thus detect
* the absence of a nameserver without timing out.
*/
+ /* With GCC 5.3 when compiling with -Os the compiler
+ emits a warning that slen may be used uninitialized,
+ but that is never true. Both slen and
+ EXT(statp).nssocks[ns] are initialized together or
+ the function return -1 before control flow reaches
+ the call to connect with slen. */
+ DIAG_PUSH_NEEDS_COMMENT;
+ DIAG_IGNORE_Os_NEEDS_COMMENT (5, "-Wmaybe-uninitialized");
if (connect(EXT(statp).nssocks[ns], nsap, slen) < 0) {
- Aerror(statp, stderr, "connect(dg)", errno, nsap);
+ DIAG_POP_NEEDS_COMMENT;
__res_iclose(statp, false);
return (0);
}
- if (__glibc_unlikely (__have_o_nonblock < 0)) {
- /* Make socket non-blocking. */
- int fl = __fcntl (EXT(statp).nssocks[ns], F_GETFL);
- if (fl != -1)
- __fcntl (EXT(statp).nssocks[ns], F_SETFL,
- fl | O_NONBLOCK);
- Dprint(statp->options & RES_DEBUG,
- (stdout, ";; new DG socket\n"))
- }
}
return 1;
}
+/* The send_dg function is responsible for sending a DNS query over UDP
+ to the nameserver numbered NS from the res_state STATP i.e.
+ EXT(statp).nssocks[ns]. The function supports IPv4 and IPv6 queries
+ along with the ability to send the query in parallel for both stacks
+ (default) or serially (RES_SINGLKUP). It also supports serial lookup
+ with a close and reopen of the socket used to talk to the server
+ (RES_SNGLKUPREOP) to work around broken name servers.
+
+ The query stored in BUF of BUFLEN length is sent first followed by
+ the query stored in BUF2 of BUFLEN2 length. Queries are sent
+ in parallel (default) or serially (RES_SINGLKUP or RES_SNGLKUPREOP).
+
+ Answers to the query are stored firstly in *ANSP up to a max of
+ *ANSSIZP bytes. If more than *ANSSIZP bytes are needed and ANSCP
+ is non-NULL (to indicate that modifying the answer buffer is allowed)
+ then malloc is used to allocate a new response buffer and ANSCP and
+ ANSP will both point to the new buffer. If more than *ANSSIZP bytes
+ are needed but ANSCP is NULL, then as much of the response as
+ possible is read into the buffer, but the results will be truncated.
+ When truncation happens because of a small answer buffer the DNS
+ packets header field TC will bet set to 1, indicating a truncated
+ message, while the rest of the UDP packet is discarded.
+
+ Answers to the query are stored secondly in *ANSP2 up to a max of
+ *ANSSIZP2 bytes, with the actual response length stored in
+ *RESPLEN2. If more than *ANSSIZP bytes are needed and ANSP2
+ is non-NULL (required for a second query) then malloc is used to
+ allocate a new response buffer, *ANSSIZP2 is set to the new buffer
+ size and *ANSP2_MALLOCED is set to 1.
+
+ The ANSP2_MALLOCED argument will eventually be removed as the
+ change in buffer pointer can be used to detect the buffer has
+ changed and that the caller should use free on the new buffer.
+
+ Note that the answers may arrive in any order from the server and
+ therefore the first and second answer buffers may not correspond to
+ the first and second queries.
+
+ It is not supported to call this function with a non-NULL ANSP2
+ but a NULL ANSCP. Put another way, you can call send_vc with a
+ single unmodifiable buffer or two modifiable buffers, but no other
+ combination is supported.
+
+ It is the caller's responsibility to free the malloc allocated
+ buffers by detecting that the pointers have changed from their
+ original values i.e. *ANSCP or *ANSP2 has changed.
+
+ If an answer is truncated because of UDP datagram DNS limits then
+ *V_CIRCUIT is set to 1 and the return value non-zero to indicate to
+ the caller to retry with TCP. The value *GOTSOMEWHERE is set to 1
+ if any progress was made reading a response from the nameserver and
+ is used by the caller to distinguish between ECONNREFUSED and
+ ETIMEDOUT (the latter if *GOTSOMEWHERE is 1).
+
+ If errors are encountered then *TERRNO is set to an appropriate
+ errno value and a zero result is returned for a recoverable error,
+ and a less-than zero result is returned for a non-recoverable error.
+
+ If no errors are encountered then *TERRNO is left unmodified and
+ a the length of the first response in bytes is returned. */
static int
send_dg(res_state statp,
const u_char *buf, int buflen, const u_char *buf2, int buflen2,
{
const HEADER *hp = (HEADER *) buf;
const HEADER *hp2 = (HEADER *) buf2;
- u_char *ans = *ansp;
- int orig_anssizp = *anssizp;
struct timespec now, timeout, finish;
struct pollfd pfd[1];
int ptimeout;
retry_reopen:
retval = reopen (statp, terrno, ns);
if (retval <= 0)
- return retval;
+ {
+ if (resplen2 != NULL)
+ *resplen2 = 0;
+ return retval;
+ }
retry:
evNowTime(&now);
evConsTime(&timeout, seconds, 0);
int need_recompute = 0;
int nwritten = 0;
int recvresp1 = 0;
+ /* Skip the second response if there is no second query.
+ To do that we mark the second response as received. */
int recvresp2 = buf2 == NULL;
pfd[0].fd = EXT(statp).nssocks[ns];
pfd[0].events = POLLOUT;
- if (resplen2 != NULL)
- *resplen2 = 0;
wait:
if (need_recompute) {
recompute_resend:
evNowTime(&now);
if (evCmpTime(finish, now) <= 0) {
poll_err_out:
- Perror(statp, stderr, "poll", errno);
- err_out:
- __res_iclose(statp, false);
- return (0);
+ return close_and_return_error (statp, resplen2);
}
evSubTime(&timeout, &finish, &now);
need_recompute = 0;
need_recompute = 1;
}
if (n == 0) {
- Dprint(statp->options & RES_DEBUG, (stdout, ";; timeout\n"));
if (resplen > 1 && (recvresp1 || (buf2 != NULL && recvresp2)))
{
/* There are quite a few broken name servers out
}
*gotsomewhere = 1;
- return (0);
+ if (resplen2 != NULL)
+ *resplen2 = 0;
+ return 0;
}
if (n < 0) {
if (errno == EINTR)
if (have_sendmmsg >= 0 && nwritten == 0 && buf2 != NULL
&& !single_request)
{
- struct iovec iov[2];
- struct mmsghdr reqs[2];
- reqs[0].msg_hdr.msg_name = NULL;
- reqs[0].msg_hdr.msg_namelen = 0;
- reqs[0].msg_hdr.msg_iov = &iov[0];
- reqs[0].msg_hdr.msg_iovlen = 1;
- iov[0].iov_base = (void *) buf;
- iov[0].iov_len = buflen;
- reqs[0].msg_hdr.msg_control = NULL;
- reqs[0].msg_hdr.msg_controllen = 0;
-
- reqs[1].msg_hdr.msg_name = NULL;
- reqs[1].msg_hdr.msg_namelen = 0;
- reqs[1].msg_hdr.msg_iov = &iov[1];
- reqs[1].msg_hdr.msg_iovlen = 1;
- iov[1].iov_base = (void *) buf2;
- iov[1].iov_len = buflen2;
- reqs[1].msg_hdr.msg_control = NULL;
- reqs[1].msg_hdr.msg_controllen = 0;
+ struct iovec iov =
+ { .iov_base = (void *) buf, .iov_len = buflen };
+ struct iovec iov2 =
+ { .iov_base = (void *) buf2, .iov_len = buflen2 };
+ struct mmsghdr reqs[2] =
+ {
+ {
+ .msg_hdr =
+ {
+ .msg_iov = &iov,
+ .msg_iovlen = 1,
+ },
+ },
+ {
+ .msg_hdr =
+ {
+ .msg_iov = &iov2,
+ .msg_iovlen = 1,
+ }
+ },
+ };
int ndg = __sendmmsg (pfd[0].fd, reqs, 2, MSG_NOSIGNAL);
if (__glibc_likely (ndg == 2))
#endif
fail_sendmmsg:
- Perror(statp, stderr, "sendmmsg", errno);
- goto err_out;
+ return close_and_return_error (statp, resplen2);
}
}
else
if (sr != (nwritten != 0 ? buflen2 : buflen)) {
if (errno == EINTR || errno == EAGAIN)
goto recompute_resend;
- Perror(statp, stderr, "send", errno);
- goto err_out;
+ return close_and_return_error (statp, resplen2);
}
just_one:
if (nwritten != 0 || buf2 == NULL || single_request)
int *thisresplenp;
if ((recvresp1 | recvresp2) == 0 || buf2 == NULL) {
+ /* We have not received any responses
+ yet or we only have one response to
+ receive. */
thisanssizp = anssizp;
thisansp = anscp ?: ansp;
assert (anscp != NULL || ansp2 == NULL);
thisresplenp = &resplen;
} else {
- if (*anssizp != MAXPACKET) {
- /* No buffer allocated for the first
- reply. We can try to use the rest
- of the user-provided buffer. */
-#if _STRING_ARCH_unaligned
- *anssizp2 = orig_anssizp - resplen;
- *ansp2 = *ansp + resplen;
-#else
- int aligned_resplen
- = ((resplen + __alignof__ (HEADER) - 1)
- & ~(__alignof__ (HEADER) - 1));
- *anssizp2 = orig_anssizp - aligned_resplen;
- *ansp2 = *ansp + aligned_resplen;
-#endif
- } else {
- /* The first reply did not fit into the
- user-provided buffer. Maybe the second
- answer will. */
- *anssizp2 = orig_anssizp;
- *ansp2 = *ansp;
- }
-
thisanssizp = anssizp2;
thisansp = ansp2;
thisresplenp = resplen2;
}
if (*thisanssizp < MAXPACKET
- /* Yes, we test ANSCP here. If we have two buffers
- both will be allocatable. */
- && anscp
+ /* If the current buffer is not the the static
+ user-supplied buffer then we can reallocate
+ it. */
+ && (thisansp != NULL && thisansp != ansp)
#ifdef FIONREAD
+ /* Is the size too small? */
&& (ioctl (pfd[0].fd, FIONREAD, thisresplenp) < 0
|| *thisanssizp < *thisresplenp)
#endif
) {
+ /* Always allocate MAXPACKET, callers expect
+ this specific size. */
u_char *newp = malloc (MAXPACKET);
if (newp != NULL) {
- *anssizp = MAXPACKET;
- *thisansp = ans = newp;
+ *thisanssizp = MAXPACKET;
+ *thisansp = newp;
if (thisansp == ansp2)
*ansp2_malloced = 1;
}
}
+ /* We could end up with truncation if anscp was NULL
+ (not allowed to change caller's buffer) and the
+ response buffer size is too small. This isn't a
+ reliable way to detect truncation because the ioctl
+ may be an inaccurate report of the UDP message size.
+ Therefore we use this only to issue debug output.
+ To do truncation accurately with UDP we need
+ MSG_TRUNC which is only available on Linux. We
+ can abstract out the Linux-specific feature in the
+ future to detect truncation. */
HEADER *anhp = (HEADER *) *thisansp;
socklen_t fromlen = sizeof(struct sockaddr_in6);
assert (sizeof(from) <= fromlen);
need_recompute = 1;
goto wait;
}
- Perror(statp, stderr, "recvfrom", errno);
- goto err_out;
+ return close_and_return_error (statp, resplen2);
}
*gotsomewhere = 1;
if (__glibc_unlikely (*thisresplenp < HFIXEDSZ)) {
/*
* Undersized message.
*/
- Dprint(statp->options & RES_DEBUG,
- (stdout, ";; undersized: %d\n",
- *thisresplenp));
*terrno = EMSGSIZE;
- goto err_out;
+ return close_and_return_error (statp, resplen2);
}
if ((recvresp1 || hp->id != anhp->id)
&& (recvresp2 || hp2->id != anhp->id)) {
* XXX - potential security hazard could
* be detected here.
*/
- DprintQ((statp->options & RES_DEBUG) ||
- (statp->pfcode & RES_PRF_REPLY),
- (stdout, ";; old answer:\n"),
- *thisansp,
- (*thisresplenp > *thisanssizp)
- ? *thisanssizp : *thisresplenp);
goto wait;
}
if (!(statp->options & RES_INSECURE1) &&
* XXX - potential security hazard could
* be detected here.
*/
- DprintQ((statp->options & RES_DEBUG) ||
- (statp->pfcode & RES_PRF_REPLY),
- (stdout, ";; not our server:\n"),
- *thisansp,
- (*thisresplenp > *thisanssizp)
- ? *thisanssizp : *thisresplenp);
goto wait;
}
-#ifdef RES_USE_EDNS0
- if (anhp->rcode == FORMERR
- && (statp->options & RES_USE_EDNS0) != 0U) {
- /*
- * Do not retry if the server does not understand
- * EDNS0. The case has to be captured here, as
- * FORMERR packet do not carry query section, hence
- * res_queriesmatch() returns 0.
- */
- DprintQ(statp->options & RES_DEBUG,
- (stdout,
- "server rejected query with EDNS0:\n"),
- *thisansp,
- (*thisresplenp > *thisanssizp)
- ? *thisanssizp : *thisresplenp);
- /* record the error */
- statp->_flags |= RES_F_EDNS0ERR;
- goto err_out;
- }
-#endif
if (!(statp->options & RES_INSECURE2)
&& (recvresp1 || !res_queriesmatch(buf, buf + buflen,
*thisansp,
* XXX - potential security hazard could
* be detected here.
*/
- DprintQ((statp->options & RES_DEBUG) ||
- (statp->pfcode & RES_PRF_REPLY),
- (stdout, ";; wrong query name:\n"),
- *thisansp,
- (*thisresplenp > *thisanssizp)
- ? *thisanssizp : *thisresplenp);
goto wait;
}
if (anhp->rcode == SERVFAIL ||
anhp->rcode == NOTIMP ||
anhp->rcode == REFUSED) {
- DprintQ(statp->options & RES_DEBUG,
- (stdout, "server rejected query:\n"),
- *thisansp,
- (*thisresplenp > *thisanssizp)
- ? *thisanssizp : *thisresplenp);
-
next_ns:
if (recvresp1 || (buf2 != NULL && recvresp2)) {
*resplen2 = 0;
goto wait;
}
- __res_iclose(statp, false);
/* don't retry if called from dig */
if (!statp->pfcode)
- return (0);
+ return close_and_return_error (statp, resplen2);
+ __res_iclose(statp, false);
}
if (anhp->rcode == NOERROR && anhp->ancount == 0
&& anhp->aa == 0 && anhp->ra == 0 && anhp->arcount == 0) {
- DprintQ(statp->options & RES_DEBUG,
- (stdout, "referred query:\n"),
- *thisansp,
- (*thisresplenp > *thisanssizp)
- ? *thisanssizp : *thisresplenp);
goto next_ns;
}
if (!(statp->options & RES_IGNTC) && anhp->tc) {
* To get the rest of answer,
* use TCP with same server.
*/
- Dprint(statp->options & RES_DEBUG,
- (stdout, ";; truncated answer\n"));
*v_circuit = 1;
__res_iclose(statp, false);
// XXX if we have received one reply we could
// XXX use it and not repeat it over TCP...
+ if (resplen2 != NULL)
+ *resplen2 = 0;
return (1);
}
/* Mark which reply we received. */
__res_iclose (statp, false);
retval = reopen (statp, terrno, ns);
if (retval <= 0)
- return retval;
+ {
+ if (resplen2 != NULL)
+ *resplen2 = 0;
+ return retval;
+ }
pfd[0].fd = EXT(statp).nssocks[ns];
}
}
goto wait;
}
- /*
- * All is well, or the error is fatal. Signal that the
- * next nameserver ought not be tried.
- */
+ /* All is well. We have received both responses (if
+ two responses were requested). */
return (resplen);
- } else if (pfd[0].revents & (POLLERR | POLLHUP | POLLNVAL)) {
- /* Something went wrong. We can stop trying. */
- goto err_out;
- }
+ } else if (pfd[0].revents & (POLLERR | POLLHUP | POLLNVAL))
+ /* Something went wrong. We can stop trying. */
+ return close_and_return_error (statp, resplen2);
else {
/* poll should not have returned > 0 in this case. */
abort ();
}
}
-#ifdef DEBUG
-static void
-Aerror(const res_state statp, FILE *file, const char *string, int error,
- const struct sockaddr *address)
-{
- int save = errno;
-
- if ((statp->options & RES_DEBUG) != 0) {
- char tmp[sizeof "xxxx.xxxx.xxxx.255.255.255.255"];
-
- fprintf(file, "res_send: %s ([%s].%u): %s\n",
- string,
- (address->sa_family == AF_INET
- ? inet_ntop(address->sa_family,
- &((const struct sockaddr_in *) address)->sin_addr,
- tmp, sizeof tmp)
- : inet_ntop(address->sa_family,
- &((const struct sockaddr_in6 *) address)->sin6_addr,
- tmp, sizeof tmp)),
- (address->sa_family == AF_INET
- ? ntohs(((struct sockaddr_in *) address)->sin_port)
- : address->sa_family == AF_INET6
- ? ntohs(((struct sockaddr_in6 *) address)->sin6_port)
- : 0),
- strerror(error));
- }
- __set_errno (save);
-}
-
-static void
-Perror(const res_state statp, FILE *file, const char *string, int error) {
- int save = errno;
-
- if ((statp->options & RES_DEBUG) != 0)
- fprintf(file, "res_send: %s: %s\n",
- string, strerror(error));
- __set_errno (save);
-}
-#endif
-
static int
sock_eq(struct sockaddr_in6 *a1, struct sockaddr_in6 *a2) {
if (a1->sin6_family == a2->sin6_family) {