1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
|
/*
* Copyright (c) 1989 - 1994, Julianne Frances Haugh
* Copyright (c) 1996 - 1997, Marek Michałkiewicz
* Copyright (c) 2005 , Tomasz Kłoczko
* Copyright (c) 2008 , Nicolas François
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the copyright holders or contributors may not be used to
* endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
* PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <config.h>
#ident "$Id$"
#include <stdio.h>
#include <ctype.h>
#include <errno.h>
#include "defines.h"
#include "prototypes.h"
#include "port.h"
static FILE *ports;
/*
* portcmp - compare the name of a port to a /etc/porttime entry
*
* portcmp works like strcmp, except that if the last character
* in a failing match is a '*', the match is considered to have
* passed. The "*" match is suppressed whenever the port is "SU",
* which is the token the "su" command uses to validate access.
* A match returns 0, failure returns non-zero.
*/
static int portcmp (const char *pattern, const char *port)
{
const char *orig = port;
while (('\0' != *pattern) && (*pattern == *port)) {
pattern++;
port++;
}
if (('\0' == *pattern) && ('\0' == *port)) {
return 0;
}
if (('S' == orig[0]) && ('U' == orig[1]) && ('\0' == orig[2])) {
return 1;
}
return (*pattern == '*') ? 0 : 1;
}
/*
* setportent - open /etc/porttime file or rewind
*
* the /etc/porttime file is rewound if already open, or
* opened for reading.
*/
static void setportent (void)
{
if (NULL != ports) {
rewind (ports);
} else {
ports = fopen (PORTS, "r");
}
}
/*
* endportent - close the /etc/porttime file
*
* the /etc/porttime file is closed and the ports variable set
* to NULL to indicate that the /etc/porttime file is no longer
* open.
*/
static void endportent (void)
{
if (NULL != ports) {
(void) fclose (ports);
}
ports = (FILE *) 0;
}
/*
* getportent - read a single entry from /etc/porttime
*
* the next line in /etc/porttime is converted to a (struct port)
* and a pointer to a static (struct port) is returned to the
* invoker. NULL is returned on either EOF or error. errno is
* set to EINVAL on error to distinguish the two conditions.
*/
static struct port *getportent (void)
{
static struct port port; /* static struct to point to */
static char buf[BUFSIZ]; /* some space for stuff */
static char *ttys[PORT_TTY + 1]; /* some pointers to tty names */
static char *users[PORT_IDS + 1]; /* some pointers to user ids */
static struct pt_time ptimes[PORT_TIMES + 1]; /* time ranges */
char *cp; /* pointer into line */
int dtime; /* scratch time of day */
int i, j;
int saveerr = errno; /* errno value on entry */
/*
* If the ports file is not open, open the file. Do not rewind
* since we want to search from the beginning each time.
*/
if (NULL == ports) {
setportent ();
}
if (NULL == ports) {
errno = saveerr;
return 0;
}
/*
* Common point for beginning a new line -
*
* - read a line, and NUL terminate
* - skip lines which begin with '#'
* - parse off the tty names
* - parse off a list of user names
* - parse off a list of days and times
*/
again:
/*
* Get the next line and remove the last character, which
* is a '\n'. Lines which begin with '#' are all ignored.
*/
if (fgets (buf, (int) sizeof buf, ports) == 0) {
errno = saveerr;
return 0;
}
if ('#' == buf[0]) {
goto again;
}
/*
* Get the name of the TTY device. It is the first colon
* separated field, and is the name of the TTY with no
* leading "/dev". The entry '*' is used to specify all
* TTY devices.
*/
buf[strlen (buf) - 1] = 0;
port.pt_names = ttys;
for (cp = buf, j = 0; j < PORT_TTY; j++) {
port.pt_names[j] = cp;
while (('\0' != *cp) && (':' != *cp) && (',' != *cp)) {
cp++;
}
if ('\0' == *cp) {
goto again; /* line format error */
}
if (':' == *cp) { /* end of tty name list */
break;
}
if (',' == *cp) { /* end of current tty name */
*cp++ = '\0';
}
}
*cp = '\0';
cp++;
port.pt_names[j + 1] = (char *) 0;
/*
* Get the list of user names. It is the second colon
* separated field, and is a comma separated list of user
* names. The entry '*' is used to specify all usernames.
* The last entry in the list is a (char *) 0 pointer.
*/
if (':' != *cp) {
port.pt_users = users;
port.pt_users[0] = cp;
for (j = 1; ':' != *cp; cp++) {
if ((',' == *cp) && (j < PORT_IDS)) {
*cp = '\0';
cp++;
port.pt_users[j] = cp;
j++;
}
}
port.pt_users[j] = 0;
} else {
port.pt_users = 0;
}
if (':' != *cp) {
goto again;
}
*cp = '\0';
cp++;
/*
* Get the list of valid times. The times field is the third
* colon separated field and is a list of days of the week and
* times during which this port may be used by this user. The
* valid days are 'Su', 'Mo', 'Tu', 'We', 'Th', 'Fr', and 'Sa'.
*
* In addition, the value 'Al' represents all 7 days, and 'Wk'
* represents the 5 weekdays.
*
* Times are given as HHMM-HHMM. The ending time may be before
* the starting time. Days are presumed to wrap at 0000.
*/
if ('\0' == *cp) {
port.pt_times = 0;
return &port;
}
port.pt_times = ptimes;
/*
* Get the next comma separated entry
*/
for (j = 0; ('\0' != *cp) && (j < PORT_TIMES); j++) {
/*
* Start off with no days of the week
*/
port.pt_times[j].t_days = 0;
/*
* Check each two letter sequence to see if it is
* one of the abbreviations for the days of the
* week or the other two values.
*/
for (i = 0;
('\0' != cp[i]) && ('\0' != cp[i + 1]) && isalpha (cp[i]);
i += 2) {
switch ((cp[i] << 8) | (cp[i + 1])) {
case ('S' << 8) | 'u':
port.pt_times[j].t_days |= 01;
break;
case ('M' << 8) | 'o':
port.pt_times[j].t_days |= 02;
break;
case ('T' << 8) | 'u':
port.pt_times[j].t_days |= 04;
break;
case ('W' << 8) | 'e':
port.pt_times[j].t_days |= 010;
break;
case ('T' << 8) | 'h':
port.pt_times[j].t_days |= 020;
break;
case ('F' << 8) | 'r':
port.pt_times[j].t_days |= 040;
break;
case ('S' << 8) | 'a':
port.pt_times[j].t_days |= 0100;
break;
case ('W' << 8) | 'k':
port.pt_times[j].t_days |= 076;
break;
case ('A' << 8) | 'l':
port.pt_times[j].t_days |= 0177;
break;
default:
errno = EINVAL;
return 0;
}
}
/*
* The default is 'Al' if no days were seen.
*/
if (0 == i) {
port.pt_times[j].t_days = 0177;
}
/*
* The start and end times are separated from each
* other by a '-'. The times are four digit numbers
* representing the times of day.
*/
for (dtime = 0; ('\0' != cp[i]) && isdigit (cp[i]); i++) {
dtime = dtime * 10 + cp[i] - '0';
}
if (('-' != cp[i]) || (dtime > 2400) || ((dtime % 100) > 59)) {
goto again;
}
port.pt_times[j].t_start = dtime;
cp = cp + i + 1;
for (dtime = 0, i = 0;
('\0' != cp[i]) && isdigit (cp[i]);
i++) {
dtime = dtime * 10 + cp[i] - '0';
}
if ( ((',' != cp[i]) && ('\0' != cp[i]))
|| (dtime > 2400)
|| ((dtime % 100) > 59)) {
goto again;
}
port.pt_times[j].t_end = dtime;
cp = cp + i + 1;
}
/*
* The end of the list is indicated by a pair of -1's for the
* start and end times.
*/
port.pt_times[j].t_start = port.pt_times[j].t_end = -1;
return &port;
}
/*
* getttyuser - get ports information for user and tty
*
* getttyuser() searches the ports file for an entry with a TTY
* and user field both of which match the supplied TTY and
* user name. The file is searched from the beginning, so the
* entries are treated as an ordered list.
*/
static struct port *getttyuser (const char *tty, const char *user)
{
int i, j;
struct port *port;
setportent ();
while ((port = getportent ()) != NULL) {
if ( (0 == port->pt_names)
|| (0 == port->pt_users)) {
continue;
}
for (i = 0; NULL != port->pt_names[i]; i++) {
if (portcmp (port->pt_names[i], tty) == 0) {
break;
}
}
if (port->pt_names[i] == 0) {
continue;
}
for (j = 0; NULL != port->pt_users[j]; j++) {
if ( (strcmp (user, port->pt_users[j]) == 0)
|| (strcmp (port->pt_users[j], "*") == 0)) {
break;
}
}
if (port->pt_users[j] != 0) {
break;
}
}
endportent ();
return port;
}
/*
* isttytime - tell if a given user may login at a particular time
*
* isttytime searches the ports file for an entry which matches
* the user name and TTY given.
*/
bool isttytime (const char *id, const char *port, time_t when)
{
int i;
int dtime;
struct port *pp;
struct tm *tm;
/*
* Try to find a matching entry for this user. Default to
* letting the user in - there are plenty of ways to have an
* entry to match all users.
*/
pp = getttyuser (port, id);
if (NULL == pp) {
return true;
}
/*
* The entry is there, but has no time entries - don't
* ever let them login.
*/
if (0 == pp->pt_times) {
return false;
}
/*
* The current time is converted to HHMM format for
* comparison against the time values in the TTY entry.
*/
tm = localtime (&when);
dtime = tm->tm_hour * 100 + tm->tm_min;
/*
* Each time entry is compared against the current
* time. For entries with the start after the end time,
* the comparison is made so that the time is between
* midnight and either the start or end time.
*/
for (i = 0; pp->pt_times[i].t_start != -1; i++) {
if (!(pp->pt_times[i].t_days & PORT_DAY (tm->tm_wday))) {
continue;
}
if (pp->pt_times[i].t_start <= pp->pt_times[i].t_end) {
if ( (dtime >= pp->pt_times[i].t_start)
&& (dtime <= pp->pt_times[i].t_end)) {
return true;
}
} else {
if ( (dtime >= pp->pt_times[i].t_start)
|| (dtime <= pp->pt_times[i].t_end)) {
return true;
}
}
}
/*
* No matching time entry was found, user shouldn't
* be let in right now.
*/
return false;
}
|