1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21 /*
22 * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
23 */
24
25 /*
26 * smbd NIC monitor.
27 */
28
29 #include <sys/types.h>
30 #include <stdlib.h>
31 #include <errno.h>
32 #include <string.h>
33 #include <unistd.h>
34 #include <signal.h>
35 #include <stdio.h>
36 #include <net/if.h>
37 #include <net/route.h>
38 #include <sys/sockio.h>
39 #include <sys/socket.h>
40 #include <netinet/in.h>
41 #include <arpa/inet.h>
42 #include <fcntl.h>
43 #include <pthread.h>
44 #include <syslog.h>
45 #include <smbsrv/libsmb.h>
46 #include "smbd.h"
47
48 #define SMBD_NICMON_ENABLE "nicmon_enable"
49 #define SMBD_NICMON_THROTTLE 100
50 #define SMBD_NICMON_DEBOUNCE 2
51
52 extern smbd_t smbd;
53
54 static boolean_t smbd_nicmon_enabled = B_TRUE;
55
56 /* Use this to stop monitoring */
57 static int eventpipe_write = -1;
58
59 /* Use this to refresh service instance */
60 static char *smbd_nicmon_caller_fmri = NULL;
61
62 static void smbd_nicmon_run_check(void);
63 static int smbd_nicmon_setup_rtsock(int);
64 static int smbd_nicmon_needscan(int);
65 static int smbd_nicmon_setup_eventpipe(int *, int *);
66 static void *smbd_nicmon_daemon(void *);
67
68 /*
69 * Start the nic monitor thread.
70 */
71 int
smbd_nicmon_start(const char * svc_fmri)72 smbd_nicmon_start(const char *svc_fmri)
73 {
74 pthread_t smbd_nicmon_tid;
75 int rc;
76
77 if (smb_nic_init() != SMB_NIC_SUCCESS)
78 return (-1);
79
80 rc = pthread_create(&smbd_nicmon_tid, NULL, smbd_nicmon_daemon, NULL);
81 if (rc != 0)
82 return (-1);
83
84 if (svc_fmri)
85 smbd_nicmon_caller_fmri = (char *)svc_fmri;
86
87 smbd_nicmon_run_check();
88 return (0);
89 }
90
91 void
smbd_nicmon_stop(void)92 smbd_nicmon_stop(void)
93 {
94 uchar_t buf = 1;
95
96 if (eventpipe_write < 0)
97 return;
98
99 (void) write(eventpipe_write, &buf, sizeof (buf));
100 smbd_nicmon_caller_fmri = NULL;
101 smb_nic_fini();
102 }
103
104 int
smbd_nicmon_refresh(void)105 smbd_nicmon_refresh(void)
106 {
107 if (smb_nic_init() != SMB_NIC_SUCCESS)
108 return (-1);
109
110 smbd_nicmon_run_check();
111 return (0);
112 }
113
114 /*
115 * The monitor is enabled unless it is explicitly
116 * disabled by setting smbd/nicmon_enable to false.
117 * smbd/nicmon_enable is not defined by default.
118 */
119 static void
smbd_nicmon_run_check(void)120 smbd_nicmon_run_check(void)
121 {
122 smb_scfhandle_t *hd;
123 uint8_t status;
124 int rc;
125
126 smbd_nicmon_enabled = B_TRUE;
127
128 if ((hd = smb_smf_scf_init(SMBD_FMRI_PREFIX)) == NULL) {
129 syslog(LOG_DEBUG,
130 "smbd_nicmon: smb_smf_scf_init failed");
131 return;
132 }
133
134 rc = smb_smf_create_service_pgroup(hd, SMBD_PG_NAME);
135 if (rc != SMBD_SMF_OK) {
136 smb_smf_scf_fini(hd);
137 syslog(LOG_DEBUG,
138 "smbd_nicmon: smb_smf_create_service_pgroup failed");
139 return;
140 }
141
142 rc = smb_smf_get_boolean_property(hd, SMBD_NICMON_ENABLE, &status);
143 if (rc == SMBD_SMF_OK && status == 0)
144 smbd_nicmon_enabled = B_FALSE;
145
146 smb_smf_scf_fini(hd);
147 }
148
149 /*
150 * Setup routing socket for getting RTM messages.
151 */
152 static int
smbd_nicmon_setup_rtsock(int af)153 smbd_nicmon_setup_rtsock(int af)
154 {
155 int sd;
156 int flags;
157
158 if ((sd = socket(PF_ROUTE, SOCK_RAW, af)) == -1) {
159 syslog(LOG_ERR,
160 "smbd_nicmon: routing socket failed: %d", errno);
161 return (-1);
162 }
163
164 if ((flags = fcntl(sd, F_GETFL, 0)) < 0) {
165 syslog(LOG_ERR,
166 "smbd_nicmon: fcntl F_GETFL failed: %d", errno);
167 (void) close(sd);
168 return (-1);
169 }
170
171 if ((fcntl(sd, F_SETFL, flags | O_NONBLOCK)) < 0) {
172 syslog(LOG_ERR,
173 "smbd_nicmon: fcntl F_SETFL failed: %d", errno);
174 (void) close(sd);
175 return (-1);
176 }
177
178 return (sd);
179 }
180
181 static int
smbd_nicmon_needscan(int sock)182 smbd_nicmon_needscan(int sock)
183 {
184 static uint32_t throttle;
185 struct rt_msghdr *rtm;
186 int64_t msg[2048 / 8];
187 int need_if_scan = 0;
188 int nbytes;
189
190 /* Read as many messages as possible and try to empty the sockets */
191 for (;;) {
192 nbytes = read(sock, msg, sizeof (msg));
193 if (nbytes <= 0)
194 break;
195
196 rtm = (struct rt_msghdr *)msg;
197 if (rtm->rtm_version != RTM_VERSION)
198 continue;
199
200 if (nbytes < rtm->rtm_msglen) {
201 if ((throttle % SMBD_NICMON_THROTTLE) == 0) {
202 syslog(LOG_DEBUG,
203 "smbd_nicmon: short read: %d of %d",
204 nbytes, rtm->rtm_msglen);
205 }
206 ++throttle;
207 continue;
208 }
209
210 switch (rtm->rtm_type) {
211 case RTM_NEWADDR:
212 case RTM_DELADDR:
213 case RTM_IFINFO:
214 need_if_scan = 1;
215 break;
216 default:
217 break;
218 }
219 }
220
221 return (need_if_scan);
222 }
223
224 /*
225 * Create pipe for signal delivery and set up signal handlers.
226 */
227 static int
smbd_nicmon_setup_eventpipe(int * read_pipe,int * write_pipe)228 smbd_nicmon_setup_eventpipe(int *read_pipe, int *write_pipe)
229 {
230 int fds[2];
231
232 if ((pipe(fds)) < 0) {
233 syslog(LOG_ERR,
234 "smbd_nicmon: event pipe failed: %d", errno);
235 return (-1);
236 }
237
238 *read_pipe = fds[0];
239 *write_pipe = fds[1];
240 return (0);
241 }
242
243 /*
244 * Create the global routing socket to monitor changes in NIC interfaces.
245 * We are only interested in new inerface addition/deletion and changes
246 * in UP/DOWN status.
247 *
248 * Note: only supports AF_INET routing socket. Need to add AF_INET6 to
249 * support IPv6.
250 */
251 /*ARGSUSED*/
252 static void *
smbd_nicmon_daemon(void * arg)253 smbd_nicmon_daemon(void *arg)
254 {
255 static uint32_t throttle;
256 static int rtsock_v4;
257 static int eventpipe_read = -1;
258 struct pollfd pollfds[2];
259 int pollfd_num = 2;
260 int i, nic_changed;
261 int rc;
262
263 if ((rtsock_v4 = smbd_nicmon_setup_rtsock(AF_INET)) == -1)
264 return (NULL);
265
266 rc = smbd_nicmon_setup_eventpipe(&eventpipe_read, &eventpipe_write);
267 if (rc != 0)
268 return (NULL);
269
270 /*
271 * Listen for activity on any of the sockets.
272 * The delay before checking the rtsock will hopefully
273 * smooth things out when there is a lot of activity.
274 */
275 for (;;) {
276 errno = 0;
277 nic_changed = 0;
278 pollfds[0].fd = rtsock_v4;
279 pollfds[0].events = POLLIN;
280 pollfds[1].fd = eventpipe_read;
281 pollfds[1].events = POLLIN;
282
283 if (poll(pollfds, pollfd_num, -1) < 0) {
284 if (errno == EINTR)
285 continue;
286 if ((throttle % SMBD_NICMON_THROTTLE) == 0)
287 syslog(LOG_DEBUG,
288 "smbd_nicmon: poll failed: %d", errno);
289 ++throttle;
290 break;
291 }
292
293 for (i = 0; i < pollfd_num; i++) {
294 if ((pollfds[i].fd < 0) ||
295 !(pollfds[i].revents & POLLIN))
296 continue;
297 if (pollfds[i].fd == rtsock_v4) {
298 (void) sleep(SMBD_NICMON_DEBOUNCE);
299 nic_changed = smbd_nicmon_needscan(rtsock_v4);
300 }
301 if (pollfds[i].fd == eventpipe_read)
302 goto done;
303 }
304
305 /*
306 * If the monitor is enabled and something has changed,
307 * refresh the registered SMF service.
308 */
309 if (smbd_nicmon_enabled && nic_changed &&
310 smbd_nicmon_caller_fmri) {
311 if (smf_refresh_instance(smbd_nicmon_caller_fmri) != 0)
312 syslog(LOG_ERR,
313 "smbd_nicmon: %s refresh failed",
314 smbd_nicmon_caller_fmri);
315 }
316 }
317 done:
318 (void) close(rtsock_v4);
319 (void) close(eventpipe_read);
320 (void) close(eventpipe_write);
321 eventpipe_write = -1;
322 return (NULL);
323 }
324