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