Revert this upstream commit:
commit 2212c1420c92a33b0e0bd9a34938c9814a56c0f7
Author: Andreas Schwab <schwab@suse.de>
Date: Thu Feb 19 15:52:08 2015 +0100
Simplify handling of nameserver configuration in resolver
Remove use of ext.nsmap member of struct __res_state and always use
an identity mapping betwen the nsaddr_list array and the ext.nsaddrs
array. The fact that a nameserver has an IPv6 address is signalled by
setting nsaddr_list[].sin_family to zero.
reverted:
Index: glibc-2.23-39-g314f6de/resolv/res_init.c
===================================================================
--- glibc-2.23-39-g314f6de.orig/resolv/res_init.c
+++ glibc-2.23-39-g314f6de/resolv/res_init.c
@@ -139,8 +139,10 @@ __res_vinit(res_state statp, int preinit
char *cp, **pp;
int n;
char buf[BUFSIZ];
- int nserv = 0; /* number of nameservers read from file */
- int have_serv6 = 0;
+ int nserv = 0; /* number of IPv4 nameservers read from file */
+#ifdef _LIBC
+ int nservall = 0; /* number of (IPv4 + IPV6) nameservers read from file */
+#endif
int haveenv = 0;
int havesearch = 0;
#ifdef RESOLVSORT
@@ -169,9 +171,15 @@ __res_vinit(res_state statp, int preinit
statp->_flags = 0;
statp->qhook = NULL;
statp->rhook = NULL;
+ statp->_u._ext.nsinit = 0;
statp->_u._ext.nscount = 0;
- for (n = 0; n < MAXNS; n++)
- statp->_u._ext.nsaddrs[n] = NULL;
+#ifdef _LIBC
+ statp->_u._ext.nscount6 = 0;
+ for (n = 0; n < MAXNS; n++) {
+ statp->_u._ext.nsaddrs[n] = NULL;
+ statp->_u._ext.nsmap[n] = MAXNS;
+ }
+#endif
/* Allow user to override the local domain definition */
if ((cp = getenv("LOCALDOMAIN")) != NULL) {
@@ -275,7 +283,11 @@ __res_vinit(res_state statp, int preinit
continue;
}
/* read nameservers to query */
+#ifdef _LIBC
+ if (MATCH(buf, "nameserver") && nservall < MAXNS) {
+#else
if (MATCH(buf, "nameserver") && nserv < MAXNS) {
+#endif
struct in_addr a;
cp = buf + sizeof("nameserver") - 1;
@@ -283,12 +295,13 @@ __res_vinit(res_state statp, int preinit
cp++;
if ((*cp != '\0') && (*cp != '\n')
&& __inet_aton(cp, &a)) {
- statp->nsaddr_list[nserv].sin_addr = a;
- statp->nsaddr_list[nserv].sin_family = AF_INET;
- statp->nsaddr_list[nserv].sin_port =
+ statp->nsaddr_list[nservall].sin_addr = a;
+ statp->nsaddr_list[nservall].sin_family = AF_INET;
+ statp->nsaddr_list[nservall].sin_port =
htons(NAMESERVER_PORT);
nserv++;
#ifdef _LIBC
+ nservall++;
} else {
struct in6_addr a6;
char *el;
@@ -330,11 +343,10 @@ __res_vinit(res_state statp, int preinit
}
}
- statp->nsaddr_list[nserv].sin_family = 0;
- statp->_u._ext.nsaddrs[nserv] = sa6;
- statp->_u._ext.nssocks[nserv] = -1;
- have_serv6 = 1;
- nserv++;
+ statp->_u._ext.nsaddrs[nservall] = sa6;
+ statp->_u._ext.nssocks[nservall] = -1;
+ statp->_u._ext.nsmap[nservall] = MAXNS + 1;
+ nservall++;
}
}
#endif
@@ -389,9 +401,10 @@ __res_vinit(res_state statp, int preinit
continue;
}
}
- statp->nscount = nserv;
+ statp->nscount = nservall;
#ifdef _LIBC
- if (have_serv6) {
+ if (nservall - nserv > 0) {
+ statp->_u._ext.nscount6 = nservall - nserv;
/* We try IPv6 servers again. */
statp->ipv6_unavail = false;
}
@@ -580,7 +593,11 @@ __res_iclose(res_state statp, bool free_
statp->_vcsock = -1;
statp->_flags &= ~(RES_F_VC | RES_F_CONN);
}
+#ifdef _LIBC
+ for (ns = 0; ns < MAXNS; ns++)
+#else
for (ns = 0; ns < statp->_u._ext.nscount; ns++)
+#endif
if (statp->_u._ext.nsaddrs[ns]) {
if (statp->_u._ext.nssocks[ns] != -1) {
close_not_cancel_no_status(statp->_u._ext.nssocks[ns]);
@@ -591,6 +608,8 @@ __res_iclose(res_state statp, bool free_
statp->_u._ext.nsaddrs[ns] = NULL;
}
}
+ if (free_addr)
+ statp->_u._ext.nsinit = 0;
}
libc_hidden_def (__res_iclose)
Index: glibc-2.23-39-g314f6de/resolv/res_send.c
===================================================================
--- glibc-2.23-39-g314f6de.orig/resolv/res_send.c
+++ glibc-2.23-39-g314f6de/resolv/res_send.c
@@ -193,7 +193,6 @@ evNowTime(struct timespec *res) {
/* Forward. */
-static struct sockaddr *get_nsaddr (res_state, int);
static int send_vc(res_state, const u_char *, int,
const u_char *, int,
u_char **, int *, int *, int, u_char **,
@@ -231,21 +230,20 @@ res_ourserver_p(const res_state statp, c
in_port_t port = in4p->sin_port;
in_addr_t addr = in4p->sin_addr.s_addr;
- for (ns = 0; ns < statp->nscount; ns++) {
+ for (ns = 0; ns < MAXNS; ns++) {
const struct sockaddr_in *srv =
- (struct sockaddr_in *) get_nsaddr (statp, ns);
+ (struct sockaddr_in *)EXT(statp).nsaddrs[ns];
- if ((srv->sin_family == AF_INET) &&
+ if ((srv != NULL) && (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 < statp->nscount; ns++) {
- const struct sockaddr_in6 *srv
- = (struct sockaddr_in6 *) get_nsaddr (statp, ns);
- if ((srv->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) &&
(srv->sin6_port == inp->sin6_port) &&
!(memcmp(&srv->sin6_addr, &in6addr_any,
sizeof (struct in6_addr)) &&
@@ -397,48 +395,80 @@ __libc_res_nsend(res_state statp, const
* If the ns_addr_list in the resolver context has changed, then
* invalidate our cached copy and the associated timing data.
*/
- if (EXT(statp).nscount != 0) {
+ if (EXT(statp).nsinit) {
int needclose = 0;
if (EXT(statp).nscount != statp->nscount)
needclose++;
else
- for (ns = 0; ns < statp->nscount; ns++) {
- if (statp->nsaddr_list[ns].sin_family != 0
+ for (ns = 0; ns < MAXNS; ns++) {
+ unsigned int map = EXT(statp).nsmap[ns];
+ if (map < MAXNS
&& !sock_eq((struct sockaddr_in6 *)
- &statp->nsaddr_list[ns],
+ &statp->nsaddr_list[map],
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).nscount == 0) {
- for (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] =
+ 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] =
malloc(sizeof (struct sockaddr_in6));
- if (EXT(statp).nsaddrs[ns] != NULL)
- memset (mempcpy(EXT(statp).nsaddrs[ns],
+ if (EXT(statp).nsaddrs[n] != NULL) {
+ memset (mempcpy(EXT(statp).nsaddrs[n],
&statp->nsaddr_list[ns],
sizeof (struct sockaddr_in)),
'\0',
sizeof (struct sockaddr_in6)
- sizeof (struct sockaddr_in));
+ EXT(statp).nssocks[n] = -1;
+ n++;
+ }
}
- EXT(statp).nscount = statp->nscount;
+ EXT(statp).nsinit = 1;
}
/*
@@ -447,37 +477,44 @@ __libc_res_nsend(res_state statp, const
*/
if (__builtin_expect ((statp->options & RES_ROTATE) != 0, 0) &&
(statp->options & RES_BLAST) == 0) {
- struct sockaddr_in ina;
- struct sockaddr_in6 *inp;
- int lastns = statp->nscount - 1;
- int fd;
-
- inp = EXT(statp).nsaddrs[0];
- ina = statp->nsaddr_list[0];
- fd = EXT(statp).nssocks[0];
- for (ns = 0; ns < lastns; ns++) {
- EXT(statp).nsaddrs[ns] = EXT(statp).nsaddrs[ns + 1];
- statp->nsaddr_list[ns] = statp->nsaddr_list[ns + 1];
- EXT(statp).nssocks[ns] = EXT(statp).nssocks[ns + 1];
- }
- EXT(statp).nsaddrs[lastns] = inp;
- statp->nsaddr_list[lastns] = ina;
- EXT(statp).nssocks[lastns] = fd;
+ 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;
+ }
}
/*
* Send request, RETRY times, or until successful.
*/
for (try = 0; try < statp->retry; try++) {
- for (ns = 0; ns < statp->nscount; ns++)
+ for (ns = 0; ns < MAXNS; ns++)
{
#ifdef DEBUG
char tmpbuf[40];
#endif
-#if defined USE_HOOKS || defined DEBUG
- struct sockaddr *nsap = get_nsaddr (statp, ns);
-#endif
+ struct sockaddr_in6 *nsap = EXT(statp).nsaddrs[ns];
+ if (nsap == NULL)
+ goto next_ns;
same_ns:
#ifdef USE_HOOKS
if (__glibc_unlikely (statp->qhook != NULL)) {
@@ -634,21 +671,6 @@ libresolv_hidden_def (res_nsend)
/* Private */
-static struct sockaddr *
-get_nsaddr (res_state statp, int n)
-{
-
- 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];
-}
-
/* 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
@@ -730,7 +752,7 @@ send_vc(res_state statp,
const HEADER *hp = (HEADER *) buf;
const HEADER *hp2 = (HEADER *) buf2;
HEADER *anhp = (HEADER *) *ansp;
- struct sockaddr *nsap = get_nsaddr (statp, ns);
+ struct sockaddr_in6 *nsap = EXT(statp).nsaddrs[ns];
int truncating, connreset, n;
/* On some architectures compiler might emit a warning indicating
'resplen' may be used uninitialized. However if buf2 == NULL
@@ -763,8 +785,8 @@ send_vc(res_state statp,
if (getpeername(statp->_vcsock,
(struct sockaddr *)&peer, &size) < 0 ||
- !sock_eq(&peer, (struct sockaddr_in6 *) nsap)) {
- __res_iclose(statp, false);
+ !sock_eq(&peer, nsap)) {
+ __res_iclose(statp, false);
statp->_flags &= ~RES_F_VC;
}
}
@@ -773,19 +795,20 @@ send_vc(res_state statp,
if (statp->_vcsock >= 0)
__res_iclose(statp, false);
- statp->_vcsock = socket(nsap->sa_family, SOCK_STREAM, 0);
+ statp->_vcsock = socket(nsap->sin6_family, SOCK_STREAM, 0);
if (statp->_vcsock < 0) {
*terrno = errno;
Perror(statp, stderr, "socket(vc)", errno);
return (-1);
}
__set_errno (0);
- if (connect(statp->_vcsock, nsap,
- nsap->sa_family == AF_INET
+ if (connect(statp->_vcsock, (struct sockaddr *)nsap,
+ nsap->sin6_family == AF_INET
? sizeof (struct sockaddr_in)
: sizeof (struct sockaddr_in6)) < 0) {
*terrno = errno;
- Aerror(statp, stderr, "connect/vc", errno, nsap);
+ Aerror(statp, stderr, "connect/vc", errno,
+ (struct sockaddr *) nsap);
__res_iclose(statp, false);
return (0);
}
@@ -979,7 +1002,8 @@ static int
reopen (res_state statp, int *terrno, int ns)
{
if (EXT(statp).nssocks[ns] == -1) {
- struct sockaddr *nsap = get_nsaddr (statp, ns);
+ struct sockaddr *nsap
+ = (struct sockaddr *) EXT(statp).nsaddrs[ns];
socklen_t slen;
/* only try IPv6 if IPv6 NS and if not failed before */