nss_dns: Remove RES_USE_INET6 handling
Commit Message
Since commit 3f8b44be0a658266adff5ece1e4bc3ce097a5dbe ("resolv:
Remove support for RES_USE_INET6 and the inet6 option"),
res_use_inet6 () always evaluates to false.
2019-05-16 Florian Weimer <fweimer@redhat.com>
* resolv/nss_dns/dns-host.c (gethostbyname3_context): Do not
perform IPv6 lookup.
(_nss_dns_gethostbyname_r): Do not request IPv4 address mapping
from gethostbyname3_context.
Comments
* Florian Weimer:
> Since commit 3f8b44be0a658266adff5ece1e4bc3ce097a5dbe ("resolv:
> Remove support for RES_USE_INET6 and the inet6 option"),
> res_use_inet6 () always evaluates to false.
>
> 2019-05-16 Florian Weimer <fweimer@redhat.com>
>
> * resolv/nss_dns/dns-host.c (gethostbyname3_context): Do not
> perform IPv6 lookup.
> (_nss_dns_gethostbyname_r): Do not request IPv4 address mapping
> from gethostbyname3_context.
I forgot to update the ChangeLog entry after making further cleanups:
2019-05-17 Florian Weimer <fweimer@redhat.com>
* resolv/nss_dns/dns-host.c (gethostbyname3_context): Do not
perform IPv6 lookup. Adjust getanswer_r call.
(_nss_dns_gethostbyname_r): Do not request IPv4 address mapping
from gethostbyname3_context.
(_nss_dns_gethostbyaddr2_r): Adjust getanswer_r call.
(getanswer_r): Remove map argument. Do not perform address
mapping.
Florian
> diff --git a/resolv/nss_dns/dns-host.c b/resolv/nss_dns/dns-host.c
> index 9c40051aff..40c23dfe00 100644
> --- a/resolv/nss_dns/dns-host.c
> +++ b/resolv/nss_dns/dns-host.c
> @@ -85,10 +85,6 @@
> #include <resolv/resolv-internal.h>
> #include <resolv/resolv_context.h>
>
> -/* Get implementations of some internal functions. */
> -#include <resolv/mapv4v6addr.h>
> -#include <resolv/mapv4v6hostent.h>
> -
> #define RESOLVSORT
>
> #if PACKETSZ > 65536
> @@ -114,7 +110,7 @@ static enum nss_status getanswer_r (struct resolv_context *ctx,
> const char *qname, int qtype,
> struct hostent *result, char *buffer,
> size_t buflen, int *errnop, int *h_errnop,
> - int map, int32_t *ttlp, char **canonp);
> + int32_t *ttlp, char **canonp);
>
> static enum nss_status gaih_getanswer (const querybuf *answer1, int anslen1,
> const querybuf *answer2, int anslen2,
> @@ -182,7 +178,6 @@ gethostbyname3_context (struct resolv_context *ctx,
> char tmp[NS_MAXDNAME];
> int size, type, n;
> const char *cp;
> - int map = 0;
> int olderr = errno;
> enum nss_status status;
>
> @@ -244,31 +239,14 @@ gethostbyname3_context (struct resolv_context *ctx,
> else
> __set_errno (olderr);
>
> - /* If we are looking for an IPv6 address and mapping is enabled
> - by having the RES_USE_INET6 bit in _res.options set, we try
> - another lookup. */
> - if (af == AF_INET6 && res_use_inet6 ())
> - n = __res_context_search (ctx, name, C_IN, T_A, host_buffer.buf->buf,
> - host_buffer.buf != orig_host_buffer
> - ? MAXPACKET : 1024, &host_buffer.ptr,
> - NULL, NULL, NULL, NULL);
> -
> - if (n < 0)
> - {
> - if (host_buffer.buf != orig_host_buffer)
> - free (host_buffer.buf);
> - return status;
> - }
> -
> - map = 1;
> -
> - result->h_addrtype = AF_INET;
> - result->h_length = INADDRSZ;
> + if (host_buffer.buf != orig_host_buffer)
> + free (host_buffer.buf);
> + return status;
> }
>
> status = getanswer_r
> (ctx, host_buffer.buf, n, name, type, result, buffer, buflen,
> - errnop, h_errnop, map, ttlp, canonp);
> + errnop, h_errnop, ttlp, canonp);
> if (host_buffer.buf != orig_host_buffer)
> free (host_buffer.buf);
> return status;
> @@ -314,13 +292,8 @@ _nss_dns_gethostbyname_r (const char *name, struct hostent *result,
> *h_errnop = NETDB_INTERNAL;
> return NSS_STATUS_UNAVAIL;
> }
> - status = NSS_STATUS_NOTFOUND;
> - if (res_use_inet6 ())
> - status = gethostbyname3_context (ctx, name, AF_INET6, result, buffer,
> - buflen, errnop, h_errnop, NULL, NULL);
> - if (status == NSS_STATUS_NOTFOUND)
> - status = gethostbyname3_context (ctx, name, AF_INET, result, buffer,
> - buflen, errnop, h_errnop, NULL, NULL);
> + status = gethostbyname3_context (ctx, name, AF_INET, result, buffer,
> + buflen, errnop, h_errnop, NULL, NULL);
> __resolv_context_put (ctx);
> return status;
> }
> @@ -547,7 +520,7 @@ _nss_dns_gethostbyaddr2_r (const void *addr, socklen_t len, int af,
>
> status = getanswer_r
> (ctx, host_buffer.buf, n, qbuf, T_PTR, result, buffer, buflen,
> - errnop, h_errnop, 0 /* XXX */, ttlp, NULL);
> + errnop, h_errnop, ttlp, NULL);
> if (host_buffer.buf != orig_host_buffer)
> free (host_buffer.buf);
> if (status != NSS_STATUS_SUCCESS)
> @@ -627,7 +600,7 @@ static enum nss_status
> getanswer_r (struct resolv_context *ctx,
> const querybuf *answer, int anslen, const char *qname, int qtype,
> struct hostent *result, char *buffer, size_t buflen,
> - int *errnop, int *h_errnop, int map, int32_t *ttlp, char **canonp)
> + int *errnop, int *h_errnop, int32_t *ttlp, char **canonp)
> {
> struct host_data
> {
> @@ -645,7 +618,6 @@ getanswer_r (struct resolv_context *ctx,
> const char *tname;
> int (*name_ok) (const char *);
> u_char packtmp[NS_MAXCDNAME];
> - int have_to_map = 0;
> uintptr_t pad = -(uintptr_t) buffer % __alignof__ (struct host_data);
> buffer += pad;
> buflen = buflen > pad ? buflen - pad : 0;
> @@ -870,9 +842,7 @@ getanswer_r (struct resolv_context *ctx,
> continue;
> }
>
> - if (type == T_A && qtype == T_AAAA && map)
> - have_to_map = 1;
> - else if (__glibc_unlikely (type != qtype))
> + if (__glibc_unlikely (type != qtype))
> {
> cp += n;
> continue; /* XXX - had_error++ ? */
> @@ -995,9 +965,6 @@ getanswer_r (struct resolv_context *ctx,
> linebuflen -= n;
> }
>
> - if (have_to_map)
> - if (map_v4v6_hostent (result, &bp, &linebuflen))
> - goto too_small;
> *h_errnop = NETDB_SUCCESS;
> return NSS_STATUS_SUCCESS;
> }
@@ -85,10 +85,6 @@
#include <resolv/resolv-internal.h>
#include <resolv/resolv_context.h>
-/* Get implementations of some internal functions. */
-#include <resolv/mapv4v6addr.h>
-#include <resolv/mapv4v6hostent.h>
-
#define RESOLVSORT
#if PACKETSZ > 65536
@@ -114,7 +110,7 @@ static enum nss_status getanswer_r (struct resolv_context *ctx,
const char *qname, int qtype,
struct hostent *result, char *buffer,
size_t buflen, int *errnop, int *h_errnop,
- int map, int32_t *ttlp, char **canonp);
+ int32_t *ttlp, char **canonp);
static enum nss_status gaih_getanswer (const querybuf *answer1, int anslen1,
const querybuf *answer2, int anslen2,
@@ -182,7 +178,6 @@ gethostbyname3_context (struct resolv_context *ctx,
char tmp[NS_MAXDNAME];
int size, type, n;
const char *cp;
- int map = 0;
int olderr = errno;
enum nss_status status;
@@ -244,31 +239,14 @@ gethostbyname3_context (struct resolv_context *ctx,
else
__set_errno (olderr);
- /* If we are looking for an IPv6 address and mapping is enabled
- by having the RES_USE_INET6 bit in _res.options set, we try
- another lookup. */
- if (af == AF_INET6 && res_use_inet6 ())
- n = __res_context_search (ctx, name, C_IN, T_A, host_buffer.buf->buf,
- host_buffer.buf != orig_host_buffer
- ? MAXPACKET : 1024, &host_buffer.ptr,
- NULL, NULL, NULL, NULL);
-
- if (n < 0)
- {
- if (host_buffer.buf != orig_host_buffer)
- free (host_buffer.buf);
- return status;
- }
-
- map = 1;
-
- result->h_addrtype = AF_INET;
- result->h_length = INADDRSZ;
+ if (host_buffer.buf != orig_host_buffer)
+ free (host_buffer.buf);
+ return status;
}
status = getanswer_r
(ctx, host_buffer.buf, n, name, type, result, buffer, buflen,
- errnop, h_errnop, map, ttlp, canonp);
+ errnop, h_errnop, ttlp, canonp);
if (host_buffer.buf != orig_host_buffer)
free (host_buffer.buf);
return status;
@@ -314,13 +292,8 @@ _nss_dns_gethostbyname_r (const char *name, struct hostent *result,
*h_errnop = NETDB_INTERNAL;
return NSS_STATUS_UNAVAIL;
}
- status = NSS_STATUS_NOTFOUND;
- if (res_use_inet6 ())
- status = gethostbyname3_context (ctx, name, AF_INET6, result, buffer,
- buflen, errnop, h_errnop, NULL, NULL);
- if (status == NSS_STATUS_NOTFOUND)
- status = gethostbyname3_context (ctx, name, AF_INET, result, buffer,
- buflen, errnop, h_errnop, NULL, NULL);
+ status = gethostbyname3_context (ctx, name, AF_INET, result, buffer,
+ buflen, errnop, h_errnop, NULL, NULL);
__resolv_context_put (ctx);
return status;
}
@@ -547,7 +520,7 @@ _nss_dns_gethostbyaddr2_r (const void *addr, socklen_t len, int af,
status = getanswer_r
(ctx, host_buffer.buf, n, qbuf, T_PTR, result, buffer, buflen,
- errnop, h_errnop, 0 /* XXX */, ttlp, NULL);
+ errnop, h_errnop, ttlp, NULL);
if (host_buffer.buf != orig_host_buffer)
free (host_buffer.buf);
if (status != NSS_STATUS_SUCCESS)
@@ -627,7 +600,7 @@ static enum nss_status
getanswer_r (struct resolv_context *ctx,
const querybuf *answer, int anslen, const char *qname, int qtype,
struct hostent *result, char *buffer, size_t buflen,
- int *errnop, int *h_errnop, int map, int32_t *ttlp, char **canonp)
+ int *errnop, int *h_errnop, int32_t *ttlp, char **canonp)
{
struct host_data
{
@@ -645,7 +618,6 @@ getanswer_r (struct resolv_context *ctx,
const char *tname;
int (*name_ok) (const char *);
u_char packtmp[NS_MAXCDNAME];
- int have_to_map = 0;
uintptr_t pad = -(uintptr_t) buffer % __alignof__ (struct host_data);
buffer += pad;
buflen = buflen > pad ? buflen - pad : 0;
@@ -870,9 +842,7 @@ getanswer_r (struct resolv_context *ctx,
continue;
}
- if (type == T_A && qtype == T_AAAA && map)
- have_to_map = 1;
- else if (__glibc_unlikely (type != qtype))
+ if (__glibc_unlikely (type != qtype))
{
cp += n;
continue; /* XXX - had_error++ ? */
@@ -995,9 +965,6 @@ getanswer_r (struct resolv_context *ctx,
linebuflen -= n;
}
- if (have_to_map)
- if (map_v4v6_hostent (result, &bp, &linebuflen))
- goto too_small;
*h_errnop = NETDB_SUCCESS;
return NSS_STATUS_SUCCESS;
}