1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1989, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 #include <sys/cdefs.h>
33 __SCCSID("@(#)getttyent.c 8.1 (Berkeley) 6/4/93");
34 __FBSDID("$FreeBSD$");
35
36 #include <sys/types.h>
37 #include <sys/stat.h>
38 #include <sys/sysctl.h>
39
40 #include <ctype.h>
41 #include <stdio.h>
42 #include <stdlib.h>
43 #include <string.h>
44 #include <ttyent.h>
45
46 static char zapchar;
47 static FILE *tf;
48 static size_t lbsize;
49 static char *line;
50
51 #define MALLOCCHUNK 100
52
53 static char *skip(char *);
54 static char *value(char *);
55
56 struct ttyent *
getttynam(const char * tty)57 getttynam(const char *tty)
58 {
59 struct ttyent *t;
60
61 if (strncmp(tty, "/dev/", 5) == 0)
62 tty += 5;
63 setttyent();
64 while ( (t = getttyent()) )
65 if (!strcmp(tty, t->ty_name))
66 break;
67 endttyent();
68 return (t);
69 }
70
71 static int
auto_tty_status(const char * ty_name)72 auto_tty_status(const char *ty_name)
73 {
74 size_t len;
75 char *buf, *cons, *nextcons;
76 int rv;
77
78 rv = TTY_IFCONSOLE;
79
80 /* Check if this is an enabled kernel console line */
81 buf = NULL;
82 if (sysctlbyname("kern.console", NULL, &len, NULL, 0) == -1)
83 return (rv); /* Errors mean don't enable */
84 buf = malloc(len);
85 if (sysctlbyname("kern.console", buf, &len, NULL, 0) == -1)
86 goto done;
87
88 if ((cons = strchr(buf, '/')) == NULL)
89 goto done;
90 *cons = '\0';
91 nextcons = buf;
92 while ((cons = strsep(&nextcons, ",")) != NULL && strlen(cons) != 0) {
93 if (strcmp(cons, ty_name) == 0) {
94 rv |= TTY_ON;
95 break;
96 }
97 }
98
99 done:
100 free(buf);
101 return (rv);
102 }
103
104 static int
auto_exists_status(const char * ty_name)105 auto_exists_status(const char *ty_name)
106 {
107 struct stat sb;
108 char *dev;
109 int rv;
110
111 rv = TTY_IFEXISTS;
112 if (*ty_name == '/')
113 asprintf(&dev, "%s", ty_name);
114 else
115 asprintf(&dev, "/dev/%s", ty_name);
116 if (dev != NULL && stat(dev, &sb) == 0)
117 rv |= TTY_ON;
118 free(dev);
119 return (rv);
120 }
121
122 struct ttyent *
getttyent(void)123 getttyent(void)
124 {
125 static struct ttyent tty;
126 char *p;
127 int c;
128 size_t i;
129
130 if (!tf && !setttyent())
131 return (NULL);
132 for (;;) {
133 if (!fgets(p = line, lbsize, tf))
134 return (NULL);
135 /* extend buffer if line was too big, and retry */
136 while (!strchr(p, '\n') && !feof(tf)) {
137 i = strlen(p);
138 lbsize += MALLOCCHUNK;
139 if ((p = realloc(line, lbsize)) == NULL) {
140 (void)endttyent();
141 return (NULL);
142 }
143 line = p;
144 if (!fgets(&line[i], lbsize - i, tf))
145 return (NULL);
146 }
147 while (isspace((unsigned char)*p))
148 ++p;
149 if (*p && *p != '#')
150 break;
151 }
152
153 #define scmp(e) !strncmp(p, e, sizeof(e) - 1) && isspace((unsigned char)p[sizeof(e) - 1])
154 #define vcmp(e) !strncmp(p, e, sizeof(e) - 1) && p[sizeof(e) - 1] == '='
155
156 zapchar = 0;
157 tty.ty_name = p;
158 tty.ty_status = 0;
159 tty.ty_window = NULL;
160 tty.ty_group = _TTYS_NOGROUP;
161
162 p = skip(p);
163 if (!*(tty.ty_getty = p))
164 tty.ty_getty = tty.ty_type = NULL;
165 else {
166 p = skip(p);
167 if (!*(tty.ty_type = p))
168 tty.ty_type = NULL;
169 else {
170 /* compatibility kludge: handle network/dialup specially */
171 if (scmp(_TTYS_DIALUP))
172 tty.ty_status |= TTY_DIALUP;
173 else if (scmp(_TTYS_NETWORK))
174 tty.ty_status |= TTY_NETWORK;
175 p = skip(p);
176 }
177 }
178
179 for (; *p; p = skip(p)) {
180 if (scmp(_TTYS_OFF))
181 tty.ty_status &= ~TTY_ON;
182 else if (scmp(_TTYS_ON))
183 tty.ty_status |= TTY_ON;
184 else if (scmp(_TTYS_ONIFCONSOLE))
185 tty.ty_status |= auto_tty_status(tty.ty_name);
186 else if (scmp(_TTYS_ONIFEXISTS))
187 tty.ty_status |= auto_exists_status(tty.ty_name);
188 else if (scmp(_TTYS_SECURE))
189 tty.ty_status |= TTY_SECURE;
190 else if (scmp(_TTYS_INSECURE))
191 tty.ty_status &= ~TTY_SECURE;
192 else if (scmp(_TTYS_DIALUP))
193 tty.ty_status |= TTY_DIALUP;
194 else if (scmp(_TTYS_NETWORK))
195 tty.ty_status |= TTY_NETWORK;
196 else if (vcmp(_TTYS_WINDOW))
197 tty.ty_window = value(p);
198 else if (vcmp(_TTYS_GROUP))
199 tty.ty_group = value(p);
200 else
201 break;
202 }
203
204 if (zapchar == '#' || *p == '#')
205 while ((c = *++p) == ' ' || c == '\t')
206 ;
207 tty.ty_comment = p;
208 if (*p == 0)
209 tty.ty_comment = 0;
210 if ((p = strchr(p, '\n')))
211 *p = '\0';
212 return (&tty);
213 }
214
215 #define QUOTED 1
216
217 /*
218 * Skip over the current field, removing quotes, and return a pointer to
219 * the next field.
220 */
221 static char *
skip(char * p)222 skip(char *p)
223 {
224 char *t;
225 int c, q;
226
227 for (q = 0, t = p; (c = *p) != '\0'; p++) {
228 if (c == '"') {
229 q ^= QUOTED; /* obscure, but nice */
230 continue;
231 }
232 if (q == QUOTED && *p == '\\' && *(p+1) == '"')
233 p++;
234 *t++ = *p;
235 if (q == QUOTED)
236 continue;
237 if (c == '#') {
238 zapchar = c;
239 *p = 0;
240 break;
241 }
242 if (c == '\t' || c == ' ' || c == '\n') {
243 zapchar = c;
244 *p++ = 0;
245 while ((c = *p) == '\t' || c == ' ' || c == '\n')
246 p++;
247 break;
248 }
249 }
250 *--t = '\0';
251 return (p);
252 }
253
254 static char *
value(char * p)255 value(char *p)
256 {
257
258 return ((p = strchr(p, '=')) ? ++p : NULL);
259 }
260
261 int
setttyent(void)262 setttyent(void)
263 {
264
265 if (line == NULL) {
266 if ((line = malloc(MALLOCCHUNK)) == NULL)
267 return (0);
268 lbsize = MALLOCCHUNK;
269 }
270 if (tf) {
271 rewind(tf);
272 return (1);
273 } else if ( (tf = fopen(_PATH_TTYS, "re")) )
274 return (1);
275 return (0);
276 }
277
278 int
endttyent(void)279 endttyent(void)
280 {
281 int rval;
282
283 /*
284 * NB: Don't free `line' because getttynam()
285 * may still be referencing it
286 */
287 if (tf) {
288 rval = (fclose(tf) != EOF);
289 tf = NULL;
290 return (rval);
291 }
292 return (1);
293 }
294
295 static int
isttystat(const char * tty,int flag)296 isttystat(const char *tty, int flag)
297 {
298 struct ttyent *t;
299
300 return ((t = getttynam(tty)) == NULL) ? 0 : !!(t->ty_status & flag);
301 }
302
303
304 int
isdialuptty(const char * tty)305 isdialuptty(const char *tty)
306 {
307
308 return isttystat(tty, TTY_DIALUP);
309 }
310
311 int
isnettty(const char * tty)312 isnettty(const char *tty)
313 {
314
315 return isttystat(tty, TTY_NETWORK);
316 }
317