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authorUlrich Drepper <drepper@redhat.com>2002-10-17 21:51:21 +0000
committerUlrich Drepper <drepper@redhat.com>2002-10-17 21:51:21 +0000
commit0420d8885a4889dca3b874c934fd5f42f2e99e5f (patch)
treedd8aecefe9a5f21d26df11cbc7f9c1dc6f2f5fd9 /resolv
parentd025fe269abcab6903b3973d193a8678228301e8 (diff)
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Update.
2002-10-15 Jakub Jelinek <jakub@redhat.com> * include/resolv.h (__libc_res_nquery, __libc_res_nsearch, __libc_res_nsend): New prototypes. * resolv/res_query.c (QUERYSIZE): Define. (__libc_res_nquery): Renamed from res_nquery. Added answerp argument. Allocate only QUERYSIZE bytes first, if res_nmkquery fails use MAXPACKET buffer. Call __libc_res_nsend instead of res_nsend, pass answerp. (res_nquery): Changed into wrapper around __libc_res_nquery. (__libc_res_nsearch): Renamed from res_nsearch. Added answerp argument. Call __libc_res_nquerydomain and __libc_res_nquery instead of the non-__libc_ variants, pass them answerp. (res_nsearch): Changed into wrapper around __libc_res_nsearch. (__libc_res_nquerydomain): Renamed from res_nquerydomain. Added answerp argument. Call __libc_res_nquery instead of res_nquery, pass answerp. (res_nquerydomain): Changed into wrapper around __libc_res_nquerydomain. * resolv/res_send.c: Include sys/ioctl.h. (MAXPACKET): Define. (send_vc): Change arguments. Reallocate answer buffer if it is too small. (send_dg): Likewise. (__libc_res_nsend): Renamed from res_nsend. Added ansp argument. Reallocate answer buffer if it is too small and hooks are in use. Adjust calls to send_vc and send_dg. (res_nsend): Changed into wrapper around __libc_res_nsend. * resolv/nss_dns/dns-host.c (_nss_dns_gethostbyname2_r): Allocate just 1K answer buffer on the stack, use __libc_res_nsearch instead of res_nsearch. (_nss_dns_gethostbyaddr_r): Similarly with __libc_res_nquery. * resolv/nss_dns/dns-network.c (_nss_dns_getnetbyaddr_r): Likewise. (_nss_dns_getnetbyname_r): Similarly with __libc_res_nsearch. * resolv/gethnamaddr.c (gethostbyname2): Likewise. (gethostbyaddr): Similarly with __libc_res_nquery. * resolv/Versions (libresolv): Export __libc_res_nquery and __libc_res_nsearch at GLIBC_PRIVATE.
Diffstat (limited to 'resolv')
-rw-r--r--resolv/Versions1
-rw-r--r--resolv/gethnamaddr.c46
-rw-r--r--resolv/nss_dns/dns-host.c60
-rw-r--r--resolv/nss_dns/dns-network.c50
-rw-r--r--resolv/res_query.c119
-rw-r--r--resolv/res_send.c96
6 files changed, 219 insertions, 153 deletions
diff --git a/resolv/Versions b/resolv/Versions
index ab6a386..09dca6a 100644
--- a/resolv/Versions
+++ b/resolv/Versions
@@ -72,6 +72,7 @@ libresolv {
# Needed in libnss_dns.
__ns_name_unpack; __ns_name_ntop;
__ns_get16; __ns_samename;
+ __libc_res_nquery; __libc_res_nsearch;
}
}
diff --git a/resolv/gethnamaddr.c b/resolv/gethnamaddr.c
index 797af94..e941b5c 100644
--- a/resolv/gethnamaddr.c
+++ b/resolv/gethnamaddr.c
@@ -510,10 +510,10 @@ gethostbyname2(name, af)
const char *name;
int af;
{
- querybuf *buf;
+ querybuf *buf, *origbuf;
register const char *cp;
char *bp;
- int n, size, type, len, use_malloc = 0;
+ int n, size, type, len;
struct hostent *ret;
extern struct hostent *_gethtbyname2();
@@ -616,24 +616,19 @@ gethostbyname2(name, af)
break;
}
- if (!__libc_use_alloca (MAXPACKET)) {
- buf = (querybuf *) malloc (sizeof (*buf));
- if (buf == NULL) {
- __set_h_errno (NETDB_INTERNAL);
- return NULL;
- }
- use_malloc = 1;
- } else
- buf = (querybuf *) alloca (sizeof (*buf));
+ buf = origbuf = (querybuf *) alloca (1024);
- if ((n = res_nsearch(&_res, name, C_IN, type, buf->buf, sizeof(buf->buf))) < 0) {
+ if ((n = __libc_res_nsearch(&_res, name, C_IN, type, buf->buf, 1024,
+ (u_char **) &buf)) < 0) {
+ if (buf != origbuf)
+ free (buf);
dprintf("res_nsearch failed (%d)\n", n);
if (errno == ECONNREFUSED)
return (_gethtbyname2(name, af));
return (NULL);
}
ret = getanswer(buf, n, name, type);
- if (use_malloc)
+ if (buf != origbuf)
free (buf);
return ret;
}
@@ -647,9 +642,9 @@ gethostbyaddr(addr, len, af)
const u_char *uaddr = (const u_char *)addr;
static const u_char mapped[] = { 0,0, 0,0, 0,0, 0,0, 0,0, 0xff,0xff };
static const u_char tunnelled[] = { 0,0, 0,0, 0,0, 0,0, 0,0, 0,0 };
- int n, use_malloc = 0;
+ int n;
socklen_t size;
- querybuf *buf;
+ querybuf *buf, *orig_buf;
register struct hostent *hp;
char qbuf[MAXDNAME+1], *qp = NULL;
#ifdef SUNSECURITY
@@ -711,23 +706,18 @@ gethostbyaddr(addr, len, af)
abort();
}
- if (!__libc_use_alloca (MAXPACKET)) {
- buf = (querybuf *) malloc (sizeof (*buf));
- if (buf == NULL) {
- __set_h_errno (NETDB_INTERNAL);
- return NULL;
- }
- use_malloc = 1;
- } else
- buf = (querybuf *) alloca (sizeof (*buf));
+ buf = orig_buf = (querybuf *) alloca (1024);
- n = res_nquery(&_res, qbuf, C_IN, T_PTR, buf->buf, sizeof buf->buf);
+ n = __libc_res_nquery(&_res, qbuf, C_IN, T_PTR, buf->buf, 1024,
+ (u_char **) &buf);
if (n < 0 && af == AF_INET6) {
strcpy(qp, "ip6.int");
- n = res_nquery(&_res, qbuf, C_IN, T_PTR, buf->buf, sizeof buf->buf);
+ n = __libc_res_nquery(&_res, qbuf, C_IN, T_PTR, buf->buf,
+ buf != orig_buf ? MAXPACKET : 1024,
+ (u_char **) &buf);
}
if (n < 0) {
- if (use_malloc)
+ if (buf != orig_buf)
free (buf);
dprintf("res_nquery failed (%d)\n", n);
if (errno == ECONNREFUSED)
@@ -735,7 +725,7 @@ gethostbyaddr(addr, len, af)
return (NULL);
}
hp = getanswer(buf, n, qbuf, T_PTR);
- if (use_malloc)
+ if (buf != orig_buf)
free (buf);
if (!hp)
return (NULL); /* h_errno was set by getanswer() */
diff --git a/resolv/nss_dns/dns-host.c b/resolv/nss_dns/dns-host.c
index 39eccab..b01dc54 100644
--- a/resolv/nss_dns/dns-host.c
+++ b/resolv/nss_dns/dns-host.c
@@ -132,11 +132,11 @@ _nss_dns_gethostbyname2_r (const char *name, int af, struct hostent *result,
char *buffer, size_t buflen, int *errnop,
int *h_errnop)
{
- querybuf *host_buffer;
+ querybuf *host_buffer, *orig_host_buffer;
char tmp[NS_MAXDNAME];
int size, type, n;
const char *cp;
- int map = 0, use_malloc = 0;
+ int map = 0;
int olderr = errno;
enum nss_status status;
@@ -170,21 +170,10 @@ _nss_dns_gethostbyname2_r (const char *name, int af, struct hostent *result,
&& (cp = res_hostalias (&_res, name, tmp, sizeof (tmp))) != NULL)
name = cp;
- if (!__libc_use_alloca (MAXPACKET))
- {
- host_buffer = (querybuf *) malloc (sizeof (querybuf));
- if (host_buffer == NULL)
- {
- *errnop = ENOMEM;
- return NSS_STATUS_UNAVAIL;
- }
- use_malloc = 1;
- }
- else
- host_buffer = (querybuf *) alloca (sizeof (querybuf));
+ host_buffer = orig_host_buffer = (querybuf *) alloca (1024);
- n = res_nsearch (&_res, name, C_IN, type, host_buffer->buf,
- sizeof (host_buffer->buf));
+ n = __libc_res_nsearch (&_res, name, C_IN, type, host_buffer->buf,
+ 1024, (u_char **) &host_buffer);
if (n < 0)
{
enum nss_status status = (errno == ECONNREFUSED
@@ -199,12 +188,13 @@ _nss_dns_gethostbyname2_r (const char *name, int af, struct hostent *result,
by having the RES_USE_INET6 bit in _res.options set, we try
another lookup. */
if (af == AF_INET6 && (_res.options & RES_USE_INET6))
- n = res_nsearch (&_res, name, C_IN, T_A, host_buffer->buf,
- sizeof (host_buffer->buf));
+ n = __libc_res_nsearch (&_res, name, C_IN, T_A, host_buffer->buf,
+ host_buffer != orig_host_buffer
+ ? MAXPACKET : 1024, (u_char **) &host_buffer);
if (n < 0)
{
- if (use_malloc)
+ if (host_buffer != orig_host_buffer)
free (host_buffer);
return status;
}
@@ -217,7 +207,7 @@ _nss_dns_gethostbyname2_r (const char *name, int af, struct hostent *result,
status = getanswer_r (host_buffer, n, name, type, result, buffer, buflen,
errnop, h_errnop, map);
- if (use_malloc)
+ if (host_buffer != orig_host_buffer)
free (host_buffer);
return status;
}
@@ -257,10 +247,10 @@ _nss_dns_gethostbyaddr_r (const void *addr, socklen_t len, int af,
char *h_addr_ptrs[MAX_NR_ADDRS + 1];
char linebuffer[0];
} *host_data = (struct host_data *) buffer;
- querybuf *host_buffer;
+ querybuf *host_buffer, *orig_host_buffer;
char qbuf[MAXDNAME+1], *qp = NULL;
size_t size;
- int n, status, use_malloc = 0;
+ int n, status;
int olderr = errno;
if ((_res.options & RES_INIT) == 0 && __res_ninit (&_res) == -1)
@@ -315,39 +305,29 @@ _nss_dns_gethostbyaddr_r (const void *addr, socklen_t len, int af,
break;
}
- if (!__libc_use_alloca (MAXPACKET))
- {
- host_buffer = (querybuf *) malloc (sizeof (querybuf));
- if (host_buffer == NULL)
- {
- *errnop = ENOMEM;
- return NSS_STATUS_UNAVAIL;
- }
- use_malloc = 1;
- }
- else
- host_buffer = (querybuf *) alloca (sizeof (querybuf));
+ host_buffer = orig_host_buffer = (querybuf *) alloca (1024);
- n = res_nquery (&_res, qbuf, C_IN, T_PTR, host_buffer->buf,
- sizeof (host_buffer->buf));
+ n = __libc_res_nquery (&_res, qbuf, C_IN, T_PTR, host_buffer->buf,
+ 1024, (u_char **) &host_buffer);
if (n < 0 && af == AF_INET6)
{
strcpy (qp, "ip6.int");
- n = res_nquery (&_res, qbuf, C_IN, T_PTR, host_buffer->buf,
- sizeof (host_buffer->buf));
+ n = __libc_res_nquery (&_res, qbuf, C_IN, T_PTR, host_buffer->buf,
+ host_buffer != orig_host_buffer
+ ? MAXPACKET : 1024, (u_char **) &host_buffer);
}
if (n < 0)
{
*h_errnop = h_errno;
__set_errno (olderr);
- if (use_malloc)
+ if (host_buffer != orig_host_buffer)
free (host_buffer);
return errno == ECONNREFUSED ? NSS_STATUS_UNAVAIL : NSS_STATUS_NOTFOUND;
}
status = getanswer_r (host_buffer, n, qbuf, T_PTR, result, buffer, buflen,
errnop, h_errnop, 0 /* XXX */);
- if (use_malloc)
+ if (host_buffer != orig_host_buffer)
free (host_buffer);
if (status != NSS_STATUS_SUCCESS)
{
diff --git a/resolv/nss_dns/dns-network.c b/resolv/nss_dns/dns-network.c
index 9a366ac..5956c84 100644
--- a/resolv/nss_dns/dns-network.c
+++ b/resolv/nss_dns/dns-network.c
@@ -110,8 +110,8 @@ _nss_dns_getnetbyname_r (const char *name, struct netent *result,
int *herrnop)
{
/* Return entry for network with NAME. */
- querybuf *net_buffer;
- int anslen, use_malloc = 0;
+ querybuf *net_buffer, *orig_net_buffer;
+ int anslen;
char *qbuf;
enum nss_status status;
@@ -120,26 +120,15 @@ _nss_dns_getnetbyname_r (const char *name, struct netent *result,
qbuf = strdupa (name);
- if (!__libc_use_alloca (MAXPACKET))
- {
- net_buffer = (querybuf *) malloc (sizeof (querybuf));
- if (net_buffer == NULL)
- {
- *errnop = ENOMEM;
- return NSS_STATUS_UNAVAIL;
- }
- use_malloc = 1;
- }
- else
- net_buffer = (querybuf *) alloca (sizeof (querybuf));
+ net_buffer = orig_net_buffer = (querybuf *) alloca (1024);
- anslen = res_nsearch (&_res, qbuf, C_IN, T_PTR, net_buffer->buf,
- sizeof (net_buffer->buf));
+ anslen = __libc_res_nsearch (&_res, qbuf, C_IN, T_PTR, net_buffer->buf,
+ 1024, (u_char **) &net_buffer);
if (anslen < 0)
{
/* Nothing found. */
*errnop = errno;
- if (use_malloc)
+ if (net_buffer != orig_net_buffer)
free (net_buffer);
return (errno == ECONNREFUSED
|| errno == EPFNOSUPPORT
@@ -148,7 +137,7 @@ _nss_dns_getnetbyname_r (const char *name, struct netent *result,
}
status = getanswer_r (net_buffer, anslen, result, buffer, buflen, BYNAME);
- if (use_malloc)
+ if (net_buffer != orig_net_buffer)
free (net_buffer);
return status;
}
@@ -161,10 +150,10 @@ _nss_dns_getnetbyaddr_r (uint32_t net, int type, struct netent *result,
{
/* Return entry for network with NAME. */
enum nss_status status;
- querybuf *net_buffer;
+ querybuf *net_buffer, *orig_net_buffer;
unsigned int net_bytes[4];
char qbuf[MAXDNAME];
- int cnt, anslen, use_malloc = 0;
+ int cnt, anslen;
u_int32_t net2;
int olderr = errno;
@@ -201,27 +190,16 @@ _nss_dns_getnetbyaddr_r (uint32_t net, int type, struct netent *result,
break;
}
- if (!__libc_use_alloca (MAXPACKET))
- {
- net_buffer = (querybuf *) malloc (sizeof (querybuf));
- if (net_buffer == NULL)
- {
- *errnop = ENOMEM;
- return NSS_STATUS_UNAVAIL;
- }
- use_malloc = 1;
- }
- else
- net_buffer = (querybuf *) alloca (sizeof (querybuf));
+ net_buffer = orig_net_buffer = (querybuf *) alloca (1024);
- anslen = res_nquery (&_res, qbuf, C_IN, T_PTR, net_buffer->buf,
- sizeof (net_buffer->buf));
+ anslen = __libc_res_nquery (&_res, qbuf, C_IN, T_PTR, net_buffer->buf,
+ 1024, (u_char **) &net_buffer);
if (anslen < 0)
{
/* Nothing found. */
int err = errno;
__set_errno (olderr);
- if (use_malloc)
+ if (net_buffer != orig_net_buffer)
free (net_buffer);
return (err == ECONNREFUSED
|| err == EPFNOSUPPORT
@@ -230,7 +208,7 @@ _nss_dns_getnetbyaddr_r (uint32_t net, int type, struct netent *result,
}
status = getanswer_r (net_buffer, anslen, result, buffer, buflen, BYADDR);
- if (use_malloc)
+ if (net_buffer != orig_net_buffer)
free (net_buffer);
if (status == NSS_STATUS_SUCCESS)
{
diff --git a/resolv/res_query.c b/resolv/res_query.c
index 968ba8b..ab4e02a 100644
--- a/resolv/res_query.c
+++ b/resolv/res_query.c
@@ -91,6 +91,13 @@ static const char rcsid[] = "$BINDId: res_query.c,v 8.20 2000/02/29 05:39:12 vix
#define MAXPACKET 65536
#endif
+#define QUERYSIZE (HFIXEDSZ + QFIXEDSZ + MAXCDNAME + 1)
+
+static int
+__libc_res_nquerydomain(res_state statp, const char *name, const char *domain,
+ int class, int type, u_char *answer, int anslen,
+ u_char **answerp);
+
/*
* Formulate a normal query, send, and await answer.
* Returned answer is placed in supplied buffer "answer".
@@ -102,11 +109,12 @@ static const char rcsid[] = "$BINDId: res_query.c,v 8.20 2000/02/29 05:39:12 vix
* Caller must parse answer and determine whether it answers the question.
*/
int
-res_nquery(res_state statp,
- const char *name, /* domain name */
- int class, int type, /* class and type of query */
- u_char *answer, /* buffer to put answer */
- int anslen) /* size of answer buffer */
+__libc_res_nquery(res_state statp,
+ const char *name, /* domain name */
+ int class, int type, /* class and type of query */
+ u_char *answer, /* buffer to put answer */
+ int anslen, /* size of answer buffer */
+ u_char **answerp) /* if buffer needs to be enlarged */
{
u_char *buf;
HEADER *hp = (HEADER *) answer;
@@ -114,15 +122,7 @@ res_nquery(res_state statp,
hp->rcode = NOERROR; /* default */
- if (!__libc_use_alloca (MAXPACKET)) {
- buf = malloc (MAXPACKET);
- if (buf == NULL) {
- __set_h_errno (NETDB_INTERNAL);
- return -1;
- }
- use_malloc = 1;
- } else
- buf = alloca (MAXPACKET);
+ buf = alloca (QUERYSIZE);
#ifdef DEBUG
if (statp->options & RES_DEBUG)
@@ -130,8 +130,18 @@ res_nquery(res_state statp,
#endif
n = res_nmkquery(statp, QUERY, name, class, type, NULL, 0, NULL,
- buf, MAXPACKET);
- if (n <= 0) {
+ buf, QUERYSIZE);
+ if (__builtin_expect (n <= 0, 0)) {
+ /* Retry just in case res_nmkquery failed because of too
+ short buffer. Shouldn't happen. */
+ buf = malloc (MAXPACKET);
+ if (buf != NULL) {
+ use_malloc = 1;
+ n = res_nmkquery(statp, QUERY, name, class, type, NULL,
+ 0, NULL, buf, MAXPACKET);
+ }
+ }
+ if (__builtin_expect (n <= 0, 0)) {
#ifdef DEBUG
if (statp->options & RES_DEBUG)
printf(";; res_query: mkquery failed\n");
@@ -141,7 +151,7 @@ res_nquery(res_state statp,
free (buf);
return (n);
}
- n = res_nsend(statp, buf, n, answer, anslen);
+ n = __libc_res_nsend(statp, buf, n, answer, anslen, answerp);
if (use_malloc)
free (buf);
if (n < 0) {
@@ -181,6 +191,17 @@ res_nquery(res_state statp,
return (n);
}
+int
+res_nquery(res_state statp,
+ const char *name, /* domain name */
+ int class, int type, /* class and type of query */
+ u_char *answer, /* buffer to put answer */
+ int anslen) /* size of answer buffer */
+{
+ return __libc_res_nquery(statp, name, class, type, answer, anslen,
+ NULL);
+}
+
/*
* Formulate a normal query, send, and retrieve answer in supplied buffer.
* Return the size of the response on success, -1 on error.
@@ -188,11 +209,12 @@ res_nquery(res_state statp,
* is detected. Error code, if any, is left in H_ERRNO.
*/
int
-res_nsearch(res_state statp,
+__libc_res_nsearch(res_state statp,
const char *name, /* domain name */
int class, int type, /* class and type of query */
u_char *answer, /* buffer to put answer */
- int anslen) /* size of answer */
+ int anslen, /* size of answer */
+ u_char **answerp)
{
const char *cp, * const *domain;
HEADER *hp = (HEADER *) answer;
@@ -214,7 +236,8 @@ res_nsearch(res_state statp,
/* If there aren't any dots, it could be a user-level alias. */
if (!dots && (cp = res_hostalias(statp, name, tmp, sizeof tmp))!= NULL)
- return (res_nquery(statp, cp, class, type, answer, anslen));
+ return (__libc_res_nquery(statp, cp, class, type, answer,
+ anslen, answerp));
/*
* If there are enough dots in the name, let's just give it a
@@ -223,12 +246,16 @@ res_nsearch(res_state statp,
*/
saved_herrno = -1;
if (dots >= statp->ndots || trailing_dot) {
- ret = res_nquerydomain(statp, name, NULL, class, type,
- answer, anslen);
+ ret = __libc_res_nquerydomain(statp, name, NULL, class, type,
+ answer, anslen, answerp);
if (ret > 0 || trailing_dot)
return (ret);
saved_herrno = h_errno;
tried_as_is++;
+ if (answerp && *answerp != answer) {
+ answer = *answerp;
+ anslen = MAXPACKET;
+ }
}
/*
@@ -249,12 +276,17 @@ res_nsearch(res_state statp,
(domain[0][0] == '.' && domain[0][1] == '\0'))
root_on_list++;
- ret = res_nquerydomain(statp, name, *domain,
- class, type,
- answer, anslen);
+ ret = __libc_res_nquerydomain(statp, name, *domain,
+ class, type,
+ answer, anslen, answerp);
if (ret > 0)
return (ret);
+ if (answerp && *answerp != answer) {
+ answer = *answerp;
+ anslen = MAXPACKET;
+ }
+
/*
* If no server present, give up.
* If name isn't found in this domain,
@@ -306,8 +338,8 @@ res_nsearch(res_state statp,
* query now.
*/
if (statp->ndots && !(tried_as_is || root_on_list)) {
- ret = res_nquerydomain(statp, name, NULL, class, type,
- answer, anslen);
+ ret = __libc_res_nquerydomain(statp, name, NULL, class, type,
+ answer, anslen, answerp);
if (ret > 0)
return (ret);
}
@@ -328,17 +360,29 @@ res_nsearch(res_state statp,
return (-1);
}
+int
+res_nsearch(res_state statp,
+ const char *name, /* domain name */
+ int class, int type, /* class and type of query */
+ u_char *answer, /* buffer to put answer */
+ int anslen) /* size of answer */
+{
+ return __libc_res_nsearch(statp, name, class, type, answer,
+ anslen, NULL);
+}
+
/*
* Perform a call on res_query on the concatenation of name and domain,
* removing a trailing dot from name if domain is NULL.
*/
-int
-res_nquerydomain(res_state statp,
+static int
+__libc_res_nquerydomain(res_state statp,
const char *name,
const char *domain,
int class, int type, /* class and type of query */
u_char *answer, /* buffer to put answer */
- int anslen) /* size of answer */
+ int anslen, /* size of answer */
+ u_char **answerp)
{
char nbuf[MAXDNAME];
const char *longname = nbuf;
@@ -374,7 +418,20 @@ res_nquerydomain(res_state statp,
}
sprintf(nbuf, "%s.%s", name, domain);
}
- return (res_nquery(statp, longname, class, type, answer, anslen));
+ return (__libc_res_nquery(statp, longname, class, type, answer,
+ anslen, answerp));
+}
+
+int
+res_nquerydomain(res_state statp,
+ const char *name,
+ const char *domain,
+ int class, int type, /* class and type of query */
+ u_char *answer, /* buffer to put answer */
+ int anslen) /* size of answer */
+{
+ return __libc_res_nquerydomain(statp, name, domain, class, type,
+ answer, anslen, NULL);
}
const char *
diff --git a/resolv/res_send.c b/resolv/res_send.c
index a163d06..d237c9a 100644
--- a/resolv/res_send.c
+++ b/resolv/res_send.c
@@ -85,6 +85,7 @@ static const char rcsid[] = "$BINDId: res_send.c,v 8.38 2000/03/30 20:16:51 vixi
#include <netinet/in.h>
#include <arpa/nameser.h>
#include <arpa/inet.h>
+#include <sys/ioctl.h>
#include <errno.h>
#include <netdb.h>
@@ -95,6 +96,12 @@ static const char rcsid[] = "$BINDId: res_send.c,v 8.38 2000/03/30 20:16:51 vixi
#include <string.h>
#include <unistd.h>
+#if PACKETSZ > 65536
+#define MAXPACKET PACKETSZ
+#else
+#define MAXPACKET 65536
+#endif
+
#ifndef _LIBC
#include <isc/eventlib.h>
#else
@@ -193,10 +200,10 @@ static const int highestFD = FD_SETSIZE - 1;
/* Forward. */
static int send_vc(res_state, const u_char *, int,
- u_char *, int, int *, int);
+ u_char **, int *, int *, int, u_char **);
static int send_dg(res_state, const u_char *, int,
- u_char *, int, int *, int,
- int *, int *);
+ u_char **, int *, int *, int,
+ int *, int *, u_char **);
#ifdef DEBUG
static void Aerror(const res_state, FILE *, const char *, int,
struct sockaddr_in);
@@ -371,8 +378,8 @@ res_queriesmatch(const u_char *buf1, const u_char *eom1,
}
int
-res_nsend(res_state statp,
- const u_char *buf, int buflen, u_char *ans, int anssiz)
+__libc_res_nsend(res_state statp, const u_char *buf, int buflen,
+ u_char *ans, int anssiz, u_char **ansp)
{
int gotsomewhere, terrno, try, v_circuit, resplen, ns, n;
@@ -380,10 +387,22 @@ res_nsend(res_state statp,
__set_errno (ESRCH);
return (-1);
}
+
if (anssiz < HFIXEDSZ) {
__set_errno (EINVAL);
return (-1);
}
+
+ if ((statp->qhook || statp->rhook) && anssiz < MAXPACKET && ansp) {
+ u_char *buf = malloc (MAXPACKET);
+ if (buf == NULL)
+ return (-1);
+ memcpy (buf, ans, HFIXEDSZ);
+ *ansp = buf;
+ ans = buf;
+ anssiz = MAXPACKET;
+ }
+
DprintQ((statp->options & RES_DEBUG) || (statp->pfcode & RES_PRF_QUERY),
(stdout, ";; res_send()\n"), buf, buflen);
v_circuit = (statp->options & RES_USEVC) || buflen > PACKETSZ;
@@ -578,8 +597,8 @@ res_nsend(res_state statp,
if (v_circuit) {
/* Use VC; at most one attempt per server. */
try = statp->retry;
- n = send_vc(statp, buf, buflen, ans, anssiz, &terrno,
- ns);
+ n = send_vc(statp, buf, buflen, &ans, &anssiz, &terrno,
+ ns, ansp);
if (n < 0)
return (-1);
if (n == 0)
@@ -587,8 +606,8 @@ res_nsend(res_state statp,
resplen = n;
} else {
/* Use datagrams. */
- n = send_dg(statp, buf, buflen, ans, anssiz, &terrno,
- ns, &v_circuit, &gotsomewhere);
+ n = send_dg(statp, buf, buflen, &ans, &anssiz, &terrno,
+ ns, &v_circuit, &gotsomewhere, ansp);
if (n < 0)
return (-1);
if (n == 0)
@@ -667,14 +686,23 @@ res_nsend(res_state statp,
return (-1);
}
+int
+res_nsend(res_state statp,
+ const u_char *buf, int buflen, u_char *ans, int anssiz)
+{
+ return __libc_res_nsend(statp, buf, buflen, ans, anssiz, NULL);
+}
+
/* Private */
static int
send_vc(res_state statp,
- const u_char *buf, int buflen, u_char *ans, int anssiz,
- int *terrno, int ns)
+ const u_char *buf, int buflen, u_char **ansp, int *anssizp,
+ int *terrno, int ns, u_char **anscp)
{
const HEADER *hp = (HEADER *) buf;
+ u_char *ans = *ansp;
+ int anssiz = *anssizp;
HEADER *anhp = (HEADER *) ans;
#ifdef _LIBC
struct sockaddr_in6 *nsap = EXT(statp).nsaddrs[ns];
@@ -782,11 +810,26 @@ send_vc(res_state statp,
}
resplen = ns_get16(ans);
if (resplen > anssiz) {
- Dprint(statp->options & RES_DEBUG,
- (stdout, ";; response truncated\n")
- );
- truncating = 1;
- len = anssiz;
+ if (anscp) {
+ ans = malloc (MAXPACKET);
+ if (ans == NULL) {
+ *terrno = ENOMEM;
+ res_nclose(statp);
+ return (0);
+ }
+ anssiz = MAXPACKET;
+ *anssizp = MAXPACKET;
+ *ansp = ans;
+ *anscp = ans;
+ anhp = (HEADER *) ans;
+ len = resplen;
+ } else {
+ Dprint(statp->options & RES_DEBUG,
+ (stdout, ";; response truncated\n")
+ );
+ truncating = 1;
+ len = anssiz;
+ }
} else
len = resplen;
if (len < HFIXEDSZ) {
@@ -851,10 +894,12 @@ send_vc(res_state statp,
static int
send_dg(res_state statp,
- const u_char *buf, int buflen, u_char *ans, int anssiz,
- int *terrno, int ns, int *v_circuit, int *gotsomewhere)
+ const u_char *buf, int buflen, u_char **ansp, int *anssizp,
+ int *terrno, int ns, int *v_circuit, int *gotsomewhere, u_char **anscp)
{
const HEADER *hp = (HEADER *) buf;
+ u_char *ans = *ansp;
+ int anssiz = *anssizp;
HEADER *anhp = (HEADER *) ans;
#ifdef _LIBC
struct sockaddr_in6 *nsap = EXT(statp).nsaddrs[ns];
@@ -992,6 +1037,21 @@ send_dg(res_state statp,
#else
fromlen = sizeof(struct sockaddr_in);
#endif
+ if (anssiz < MAXPACKET
+ && anscp
+ && (ioctl (s, FIONREAD, &resplen) < 0
+ || anssiz < resplen)) {
+ ans = malloc (MAXPACKET);
+ if (ans == NULL)
+ ans = *ansp;
+ else {
+ anssiz = MAXPACKET;
+ *anssizp = MAXPACKET;
+ *ansp = ans;
+ *anscp = ans;
+ anhp = (HEADER *) ans;
+ }
+ }
resplen = recvfrom(s, (char*)ans, anssiz,0,
(struct sockaddr *)&from, &fromlen);
if (resplen <= 0) {