s3: Avoid a potential 100% CPU loop in winbindd
[Samba.git] / nsswitch / wins.c
blobe0aa2ad8f55b77c2ee8243111c52aedc090fa0e1
1 /*
2 Unix SMB/CIFS implementation.
3 a WINS nsswitch module
4 Copyright (C) Andrew Tridgell 1999
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>.
21 #include "includes.h"
22 #include "nsswitch/winbind_nss.h"
24 #ifdef HAVE_NS_API_H
26 #include <ns_daemon.h>
27 #endif
29 #if HAVE_PTHREAD_H
30 #include <pthread.h>
31 #endif
33 #if HAVE_PTHREAD
34 static pthread_mutex_t wins_nss_mutex = PTHREAD_MUTEX_INITIALIZER;
35 #endif
37 #ifndef INADDRSZ
38 #define INADDRSZ 4
39 #endif
41 static int initialised;
43 NSS_STATUS _nss_wins_gethostbyname_r(const char *hostname, struct hostent *he,
44 char *buffer, size_t buflen, int *h_errnop);
45 NSS_STATUS _nss_wins_gethostbyname2_r(const char *name, int af, struct hostent *he,
46 char *buffer, size_t buflen, int *h_errnop);
48 static void nss_wins_init(void)
50 initialised = 1;
51 load_case_tables_library();
52 lp_set_cmdline("log level", "0");
54 TimeInit();
55 setup_logging("nss_wins",False);
56 lp_load(get_dyn_CONFIGFILE(),True,False,False,True);
57 load_interfaces();
60 static struct in_addr *lookup_byname_backend(const char *name, int *count)
62 struct ip_service *address = NULL;
63 struct in_addr *ret = NULL;
64 int j;
66 if (!initialised) {
67 nss_wins_init();
70 *count = 0;
72 /* always try with wins first */
73 if (NT_STATUS_IS_OK(resolve_wins(name,0x00,&address,count))) {
74 if ( (ret = SMB_MALLOC_P(struct in_addr)) == NULL ) {
75 free( address );
76 return NULL;
78 if (address[0].ss.ss_family != AF_INET) {
79 free(address);
80 free(ret);
81 return NULL;
83 *ret = ((struct sockaddr_in *)(void *)&address[0].ss)
84 ->sin_addr;
85 free( address );
86 return ret;
89 /* uggh, we have to broadcast to each interface in turn */
90 for (j=iface_count() - 1;j >= 0;j--) {
91 const struct in_addr *bcast = iface_n_bcast_v4(j);
92 struct sockaddr_storage ss;
93 struct sockaddr_storage *pss;
94 NTSTATUS status;
96 if (!bcast) {
97 continue;
99 in_addr_to_sockaddr_storage(&ss, *bcast);
100 status = name_query(name, 0x00, True, True, &ss,
101 NULL, &pss, count, NULL);
102 if (pss) {
103 if ((ret = SMB_MALLOC_P(struct in_addr)) == NULL) {
104 return NULL;
106 *ret = ((struct sockaddr_in *)pss)->sin_addr;
107 TALLOC_FREE(pss);
108 break;
112 return ret;
115 #ifdef HAVE_NS_API_H
117 static struct node_status *lookup_byaddr_backend(char *addr, int *count)
119 struct sockaddr_storage ss;
120 struct nmb_name nname;
121 struct node_status *result;
122 NTSTATUS status;
124 if (!initialised) {
125 nss_wins_init();
128 make_nmb_name(&nname, "*", 0);
129 if (!interpret_string_addr(&ss, addr, AI_NUMERICHOST)) {
130 return NULL;
132 status = node_status_query(NULL, &nname, &ss, &result, count, NULL);
133 if (!NT_STATUS_IS_OK(status)) {
134 return NULL;
137 return result;
140 /* IRIX version */
142 int init(void)
144 nsd_logprintf(NSD_LOG_MIN, "entering init (wins)\n");
145 nss_wins_init();
146 return NSD_OK;
149 int lookup(nsd_file_t *rq)
151 char *map;
152 char *key;
153 char *addr;
154 struct in_addr *ip_list;
155 struct node_status *status;
156 int i, count, len, size;
157 char response[1024];
158 bool found = False;
160 nsd_logprintf(NSD_LOG_MIN, "entering lookup (wins)\n");
161 if (! rq)
162 return NSD_ERROR;
164 map = nsd_attr_fetch_string(rq->f_attrs, "table", (char*)0);
165 if (! map) {
166 rq->f_status = NS_FATAL;
167 return NSD_ERROR;
170 key = nsd_attr_fetch_string(rq->f_attrs, "key", (char*)0);
171 if (! key || ! *key) {
172 rq->f_status = NS_FATAL;
173 return NSD_ERROR;
176 response[0] = '\0';
177 len = sizeof(response) - 2;
180 * response needs to be a string of the following format
181 * ip_address[ ip_address]*\tname[ alias]*
183 if (StrCaseCmp(map,"hosts.byaddr") == 0) {
184 if ( status = lookup_byaddr_backend(key, &count)) {
185 size = strlen(key) + 1;
186 if (size > len) {
187 talloc_free(status);
188 return NSD_ERROR;
190 len -= size;
191 strncat(response,key,size);
192 strncat(response,"\t",1);
193 for (i = 0; i < count; i++) {
194 /* ignore group names */
195 if (status[i].flags & 0x80) continue;
196 if (status[i].type == 0x20) {
197 size = sizeof(status[i].name) + 1;
198 if (size > len) {
199 talloc_free(status);
200 return NSD_ERROR;
202 len -= size;
203 strncat(response, status[i].name, size);
204 strncat(response, " ", 1);
205 found = True;
208 response[strlen(response)-1] = '\n';
209 talloc_free(status);
211 } else if (StrCaseCmp(map,"hosts.byname") == 0) {
212 if (ip_list = lookup_byname_backend(key, &count)) {
213 for (i = count; i ; i--) {
214 addr = inet_ntoa(ip_list[i-1]);
215 size = strlen(addr) + 1;
216 if (size > len) {
217 free(ip_list);
218 return NSD_ERROR;
220 len -= size;
221 if (i != 0)
222 response[strlen(response)-1] = ' ';
223 strncat(response,addr,size);
224 strncat(response,"\t",1);
226 size = strlen(key) + 1;
227 if (size > len) {
228 free(ip_list);
229 return NSD_ERROR;
231 strncat(response,key,size);
232 strncat(response,"\n",1);
233 found = True;
234 free(ip_list);
238 if (found) {
239 nsd_logprintf(NSD_LOG_LOW, "lookup (wins %s) %s\n",map,response);
240 nsd_set_result(rq,NS_SUCCESS,response,strlen(response),VOLATILE);
241 return NSD_OK;
243 nsd_logprintf(NSD_LOG_LOW, "lookup (wins) not found\n");
244 rq->f_status = NS_NOTFOUND;
245 return NSD_NEXT;
248 #else
250 /* Allocate some space from the nss static buffer. The buffer and buflen
251 are the pointers passed in by the C library to the _nss_*_*
252 functions. */
254 static char *get_static(char **buffer, size_t *buflen, int len)
256 char *result;
258 /* Error check. We return false if things aren't set up right, or
259 there isn't enough buffer space left. */
261 if ((buffer == NULL) || (buflen == NULL) || (*buflen < len)) {
262 return NULL;
265 /* Return an index into the static buffer */
267 result = *buffer;
268 *buffer += len;
269 *buflen -= len;
271 return result;
274 /****************************************************************************
275 gethostbyname() - we ignore any domain portion of the name and only
276 handle names that are at most 15 characters long
277 **************************************************************************/
278 NSS_STATUS
279 _nss_wins_gethostbyname_r(const char *hostname, struct hostent *he,
280 char *buffer, size_t buflen, int *h_errnop)
282 NSS_STATUS nss_status = NSS_STATUS_SUCCESS;
283 struct in_addr *ip_list;
284 int i, count;
285 fstring name;
286 size_t namelen;
287 TALLOC_CTX *frame;
289 #if HAVE_PTHREAD
290 pthread_mutex_lock(&wins_nss_mutex);
291 #endif
293 frame = talloc_stackframe();
295 memset(he, '\0', sizeof(*he));
296 fstrcpy(name, hostname);
298 /* Do lookup */
300 ip_list = lookup_byname_backend(name, &count);
302 if (!ip_list) {
303 nss_status = NSS_STATUS_NOTFOUND;
304 goto out;
307 /* Copy h_name */
309 namelen = strlen(name) + 1;
311 if ((he->h_name = get_static(&buffer, &buflen, namelen)) == NULL) {
312 free(ip_list);
313 nss_status = NSS_STATUS_TRYAGAIN;
314 goto out;
317 memcpy(he->h_name, name, namelen);
319 /* Copy h_addr_list, align to pointer boundary first */
321 if ((i = (unsigned long)(buffer) % sizeof(char*)) != 0)
322 i = sizeof(char*) - i;
324 if (get_static(&buffer, &buflen, i) == NULL) {
325 free(ip_list);
326 nss_status = NSS_STATUS_TRYAGAIN;
327 goto out;
330 if ((he->h_addr_list = (char **)get_static(
331 &buffer, &buflen, (count + 1) * sizeof(char *))) == NULL) {
332 free(ip_list);
333 nss_status = NSS_STATUS_TRYAGAIN;
334 goto out;
337 for (i = 0; i < count; i++) {
338 if ((he->h_addr_list[i] = get_static(&buffer, &buflen,
339 INADDRSZ)) == NULL) {
340 free(ip_list);
341 nss_status = NSS_STATUS_TRYAGAIN;
342 goto out;
344 memcpy(he->h_addr_list[i], &ip_list[i], INADDRSZ);
347 he->h_addr_list[count] = NULL;
349 free(ip_list);
351 /* Set h_addr_type and h_length */
353 he->h_addrtype = AF_INET;
354 he->h_length = INADDRSZ;
356 /* Set h_aliases */
358 if ((i = (unsigned long)(buffer) % sizeof(char*)) != 0)
359 i = sizeof(char*) - i;
361 if (get_static(&buffer, &buflen, i) == NULL) {
362 nss_status = NSS_STATUS_TRYAGAIN;
363 goto out;
366 if ((he->h_aliases = (char **)get_static(
367 &buffer, &buflen, sizeof(char *))) == NULL) {
368 nss_status = NSS_STATUS_TRYAGAIN;
369 goto out;
372 he->h_aliases[0] = NULL;
374 nss_status = NSS_STATUS_SUCCESS;
376 out:
378 TALLOC_FREE(frame);
380 #if HAVE_PTHREAD
381 pthread_mutex_unlock(&wins_nss_mutex);
382 #endif
383 return nss_status;
387 NSS_STATUS
388 _nss_wins_gethostbyname2_r(const char *name, int af, struct hostent *he,
389 char *buffer, size_t buflen, int *h_errnop)
391 NSS_STATUS nss_status;
393 if(af!=AF_INET) {
394 *h_errnop = NO_DATA;
395 nss_status = NSS_STATUS_UNAVAIL;
396 } else {
397 nss_status = _nss_wins_gethostbyname_r(
398 name, he, buffer, buflen, h_errnop);
400 return nss_status;
402 #endif