+2019-01-18 Florian Weimer <fweimer@redhat.com>
+
+ [BZ #24112]
+ resolv: Do not send queries for non-host-names in nss_dns.
+ * resolv/nss_dns/dns-host.c (check_name): New function.
+ (_nss_dns_gethostbyname2_r): Use it.
+ (_nss_dns_gethostbyname_r): Likewise.
+ (_nss_dns_gethostbyname4_r): Likewise.
+
2019-01-21 Florian Weimer <fweimer@redhat.com>
* resolv/inet_addr.c: Reformat to GNU style.
return status;
}
+/* Verify that the name looks like a host name. There is no point in
+ sending a query which will not produce a usable name in the
+ response. */
+static enum nss_status
+check_name (const char *name, int *h_errnop)
+{
+ if (res_hnok (name))
+ return NSS_STATUS_SUCCESS;
+ *h_errnop = HOST_NOT_FOUND;
+ return NSS_STATUS_NOTFOUND;
+}
+
enum nss_status
_nss_dns_gethostbyname2_r (const char *name, int af, struct hostent *result,
char *buffer, size_t buflen, int *errnop,
int *h_errnop)
{
+ enum nss_status status = check_name (name, h_errnop);
+ if (status != NSS_STATUS_SUCCESS)
+ return status;
return _nss_dns_gethostbyname3_r (name, af, result, buffer, buflen, errnop,
h_errnop, NULL, NULL);
}
char *buffer, size_t buflen, int *errnop,
int *h_errnop)
{
+ enum nss_status status = check_name (name, h_errnop);
+ if (status != NSS_STATUS_SUCCESS)
+ return status;
struct resolv_context *ctx = __resolv_context_get ();
if (ctx == NULL)
{
*h_errnop = NETDB_INTERNAL;
return NSS_STATUS_UNAVAIL;
}
- enum nss_status status = NSS_STATUS_NOTFOUND;
+ status = NSS_STATUS_NOTFOUND;
if (res_use_inet6 ())
status = gethostbyname3_context (ctx, name, AF_INET6, result, buffer,
buflen, errnop, h_errnop, NULL, NULL);
char *buffer, size_t buflen, int *errnop,
int *herrnop, int32_t *ttlp)
{
+ enum nss_status status = check_name (name, herrnop);
+ if (status != NSS_STATUS_SUCCESS)
+ return status;
struct resolv_context *ctx = __resolv_context_get ();
if (ctx == NULL)
{
int ans2p_malloced = 0;
int olderr = errno;
- enum nss_status status;
int n = __res_context_search (ctx, name, C_IN, T_QUERY_A_AND_AAAA,
host_buffer.buf->buf, 2048, &host_buffer.ptr,
&ans2p, &nans2p, &resplen2, &ans2p_malloced);