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 #include <sys/types.h>
35 #include <sys/stat.h>
36 #include <sys/sysctl.h>
37
38 #include <ctype.h>
39 #include <stdio.h>
40 #include <stdlib.h>
41 #include <string.h>
42 #include <ttyent.h>
43
44 static char zapchar;
45 static FILE *tf;
46 static size_t lbsize;
47 static char *line;
48
49 #define MALLOCCHUNK 100
50
51 static char *skip(char *);
52 static char *value(char *);
53
54 struct ttyent *
getttynam(const char * tty)55 getttynam(const char *tty)
56 {
57 struct ttyent *t;
58
59 if (strncmp(tty, "/dev/", 5) == 0)
60 tty += 5;
61 setttyent();
62 while ( (t = getttyent()) )
63 if (!strcmp(tty, t->ty_name))
64 break;
65 endttyent();
66 return (t);
67 }
68
69 static int
auto_tty_status(const char * ty_name)70 auto_tty_status(const char *ty_name)
71 {
72 size_t len;
73 char *buf, *cons, *nextcons;
74 int rv;
75
76 rv = TTY_IFCONSOLE;
77
78 /* Check if this is an enabled kernel console line */
79 buf = NULL;
80 if (sysctlbyname("kern.console", NULL, &len, NULL, 0) == -1)
81 return (rv); /* Errors mean don't enable */
82 buf = malloc(len);
83 if (sysctlbyname("kern.console", buf, &len, NULL, 0) == -1)
84 goto done;
85
86 if ((cons = strchr(buf, '/')) == NULL)
87 goto done;
88 *cons = '\0';
89 nextcons = buf;
90 while ((cons = strsep(&nextcons, ",")) != NULL && strlen(cons) != 0) {
91 if (strcmp(cons, ty_name) == 0) {
92 rv |= TTY_ON;
93 break;
94 }
95 }
96
97 done:
98 free(buf);
99 return (rv);
100 }
101
102 static int
auto_exists_status(const char * ty_name)103 auto_exists_status(const char *ty_name)
104 {
105 struct stat sb;
106 char *dev;
107 int rv;
108
109 rv = TTY_IFEXISTS;
110 if (*ty_name == '/')
111 asprintf(&dev, "%s", ty_name);
112 else
113 asprintf(&dev, "/dev/%s", ty_name);
114 if (dev != NULL && stat(dev, &sb) == 0)
115 rv |= TTY_ON;
116 free(dev);
117 return (rv);
118 }
119
120 struct ttyent *
getttyent(void)121 getttyent(void)
122 {
123 static struct ttyent tty;
124 char *p;
125 int c;
126 size_t i;
127
128 if (!tf && !setttyent())
129 return (NULL);
130 for (;;) {
131 if (!fgets(p = line, lbsize, tf))
132 return (NULL);
133 /* extend buffer if line was too big, and retry */
134 while (!strchr(p, '\n') && !feof(tf)) {
135 i = strlen(p);
136 lbsize += MALLOCCHUNK;
137 if ((p = realloc(line, lbsize)) == NULL) {
138 (void)endttyent();
139 return (NULL);
140 }
141 line = p;
142 if (!fgets(&line[i], lbsize - i, tf))
143 return (NULL);
144 }
145 while (isspace((unsigned char)*p))
146 ++p;
147 if (*p && *p != '#')
148 break;
149 }
150
151 #define scmp(e) !strncmp(p, e, sizeof(e) - 1) && isspace((unsigned char)p[sizeof(e) - 1])
152 #define vcmp(e) !strncmp(p, e, sizeof(e) - 1) && p[sizeof(e) - 1] == '='
153
154 zapchar = 0;
155 tty.ty_name = p;
156 tty.ty_status = 0;
157 tty.ty_window = NULL;
158 tty.ty_group = _TTYS_NOGROUP;
159
160 p = skip(p);
161 if (!*(tty.ty_getty = p))
162 tty.ty_getty = tty.ty_type = NULL;
163 else {
164 p = skip(p);
165 if (!*(tty.ty_type = p))
166 tty.ty_type = NULL;
167 else {
168 /* compatibility kludge: handle network/dialup specially */
169 if (scmp(_TTYS_DIALUP))
170 tty.ty_status |= TTY_DIALUP;
171 else if (scmp(_TTYS_NETWORK))
172 tty.ty_status |= TTY_NETWORK;
173 p = skip(p);
174 }
175 }
176
177 for (; *p; p = skip(p)) {
178 if (scmp(_TTYS_OFF))
179 tty.ty_status &= ~TTY_ON;
180 else if (scmp(_TTYS_ON))
181 tty.ty_status |= TTY_ON;
182 else if (scmp(_TTYS_ONIFCONSOLE))
183 tty.ty_status |= auto_tty_status(tty.ty_name);
184 else if (scmp(_TTYS_ONIFEXISTS))
185 tty.ty_status |= auto_exists_status(tty.ty_name);
186 else if (scmp(_TTYS_SECURE))
187 tty.ty_status |= TTY_SECURE;
188 else if (scmp(_TTYS_INSECURE))
189 tty.ty_status &= ~TTY_SECURE;
190 else if (scmp(_TTYS_DIALUP))
191 tty.ty_status |= TTY_DIALUP;
192 else if (scmp(_TTYS_NETWORK))
193 tty.ty_status |= TTY_NETWORK;
194 else if (vcmp(_TTYS_WINDOW))
195 tty.ty_window = value(p);
196 else if (vcmp(_TTYS_GROUP))
197 tty.ty_group = value(p);
198 else
199 break;
200 }
201
202 if (zapchar == '#' || *p == '#')
203 while ((c = *++p) == ' ' || c == '\t')
204 ;
205 tty.ty_comment = p;
206 if (*p == 0)
207 tty.ty_comment = 0;
208 if ((p = strchr(p, '\n')))
209 *p = '\0';
210 return (&tty);
211 }
212
213 #define QUOTED 1
214
215 /*
216 * Skip over the current field, removing quotes, and return a pointer to
217 * the next field.
218 */
219 static char *
skip(char * p)220 skip(char *p)
221 {
222 char *t;
223 int c, q;
224
225 for (q = 0, t = p; (c = *p) != '\0'; p++) {
226 if (c == '"') {
227 q ^= QUOTED; /* obscure, but nice */
228 continue;
229 }
230 if (q == QUOTED && *p == '\\' && *(p+1) == '"')
231 p++;
232 *t++ = *p;
233 if (q == QUOTED)
234 continue;
235 if (c == '#') {
236 zapchar = c;
237 *p = 0;
238 break;
239 }
240 if (c == '\t' || c == ' ' || c == '\n') {
241 zapchar = c;
242 *p++ = 0;
243 while ((c = *p) == '\t' || c == ' ' || c == '\n')
244 p++;
245 break;
246 }
247 }
248 *--t = '\0';
249 return (p);
250 }
251
252 static char *
value(char * p)253 value(char *p)
254 {
255
256 return ((p = strchr(p, '=')) ? ++p : NULL);
257 }
258
259 int
setttyent(void)260 setttyent(void)
261 {
262
263 if (line == NULL) {
264 if ((line = malloc(MALLOCCHUNK)) == NULL)
265 return (0);
266 lbsize = MALLOCCHUNK;
267 }
268 if (tf) {
269 rewind(tf);
270 return (1);
271 } else if ( (tf = fopen(_PATH_TTYS, "re")) )
272 return (1);
273 return (0);
274 }
275
276 int
endttyent(void)277 endttyent(void)
278 {
279 int rval;
280
281 /*
282 * NB: Don't free `line' because getttynam()
283 * may still be referencing it
284 */
285 if (tf) {
286 rval = (fclose(tf) != EOF);
287 tf = NULL;
288 return (rval);
289 }
290 return (1);
291 }
292
293 static int
isttystat(const char * tty,int flag)294 isttystat(const char *tty, int flag)
295 {
296 struct ttyent *t;
297
298 return ((t = getttynam(tty)) == NULL) ? 0 : !!(t->ty_status & flag);
299 }
300
301
302 int
isdialuptty(const char * tty)303 isdialuptty(const char *tty)
304 {
305
306 return isttystat(tty, TTY_DIALUP);
307 }
308
309 int
isnettty(const char * tty)310 isnettty(const char *tty)
311 {
312
313 return isttystat(tty, TTY_NETWORK);
314 }
315