xref: /openbsd/usr.bin/ssh/misc.c (revision db3296cf)
1 /*
2  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  *
13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
14  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
15  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
16  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
17  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
18  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
19  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
20  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
21  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
22  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
23  */
24 
25 #include "includes.h"
26 RCSID("$OpenBSD: misc.c,v 1.21 2003/04/12 10:15:36 markus Exp $");
27 
28 #include "misc.h"
29 #include "log.h"
30 #include "xmalloc.h"
31 
32 /* remove newline at end of string */
33 char *
34 chop(char *s)
35 {
36 	char *t = s;
37 	while (*t) {
38 		if (*t == '\n' || *t == '\r') {
39 			*t = '\0';
40 			return s;
41 		}
42 		t++;
43 	}
44 	return s;
45 
46 }
47 
48 /* set/unset filedescriptor to non-blocking */
49 void
50 set_nonblock(int fd)
51 {
52 	int val;
53 
54 	val = fcntl(fd, F_GETFL, 0);
55 	if (val < 0) {
56 		error("fcntl(%d, F_GETFL, 0): %s", fd, strerror(errno));
57 		return;
58 	}
59 	if (val & O_NONBLOCK) {
60 		debug2("fd %d is O_NONBLOCK", fd);
61 		return;
62 	}
63 	debug2("fd %d setting O_NONBLOCK", fd);
64 	val |= O_NONBLOCK;
65 	if (fcntl(fd, F_SETFL, val) == -1)
66 		debug("fcntl(%d, F_SETFL, O_NONBLOCK): %s",
67 		    fd, strerror(errno));
68 }
69 
70 void
71 unset_nonblock(int fd)
72 {
73 	int val;
74 
75 	val = fcntl(fd, F_GETFL, 0);
76 	if (val < 0) {
77 		error("fcntl(%d, F_GETFL, 0): %s", fd, strerror(errno));
78 		return;
79 	}
80 	if (!(val & O_NONBLOCK)) {
81 		debug2("fd %d is not O_NONBLOCK", fd);
82 		return;
83 	}
84 	debug("fd %d clearing O_NONBLOCK", fd);
85 	val &= ~O_NONBLOCK;
86 	if (fcntl(fd, F_SETFL, val) == -1)
87 		debug("fcntl(%d, F_SETFL, O_NONBLOCK): %s",
88 		    fd, strerror(errno));
89 }
90 
91 /* disable nagle on socket */
92 void
93 set_nodelay(int fd)
94 {
95 	int opt;
96 	socklen_t optlen;
97 
98 	optlen = sizeof opt;
99 	if (getsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &opt, &optlen) == -1) {
100 		error("getsockopt TCP_NODELAY: %.100s", strerror(errno));
101 		return;
102 	}
103 	if (opt == 1) {
104 		debug2("fd %d is TCP_NODELAY", fd);
105 		return;
106 	}
107 	opt = 1;
108 	debug2("fd %d setting TCP_NODELAY", fd);
109 	if (setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &opt, sizeof opt) == -1)
110 		error("setsockopt TCP_NODELAY: %.100s", strerror(errno));
111 }
112 
113 /* Characters considered whitespace in strsep calls. */
114 #define WHITESPACE " \t\r\n"
115 
116 /* return next token in configuration line */
117 char *
118 strdelim(char **s)
119 {
120 	char *old;
121 	int wspace = 0;
122 
123 	if (*s == NULL)
124 		return NULL;
125 
126 	old = *s;
127 
128 	*s = strpbrk(*s, WHITESPACE "=");
129 	if (*s == NULL)
130 		return (old);
131 
132 	/* Allow only one '=' to be skipped */
133 	if (*s[0] == '=')
134 		wspace = 1;
135 	*s[0] = '\0';
136 
137 	*s += strspn(*s + 1, WHITESPACE) + 1;
138 	if (*s[0] == '=' && !wspace)
139 		*s += strspn(*s + 1, WHITESPACE) + 1;
140 
141 	return (old);
142 }
143 
144 struct passwd *
145 pwcopy(struct passwd *pw)
146 {
147 	struct passwd *copy = xmalloc(sizeof(*copy));
148 
149 	memset(copy, 0, sizeof(*copy));
150 	copy->pw_name = xstrdup(pw->pw_name);
151 	copy->pw_passwd = xstrdup(pw->pw_passwd);
152 	copy->pw_gecos = xstrdup(pw->pw_gecos);
153 	copy->pw_uid = pw->pw_uid;
154 	copy->pw_gid = pw->pw_gid;
155 	copy->pw_expire = pw->pw_expire;
156 	copy->pw_change = pw->pw_change;
157 	copy->pw_class = xstrdup(pw->pw_class);
158 	copy->pw_dir = xstrdup(pw->pw_dir);
159 	copy->pw_shell = xstrdup(pw->pw_shell);
160 	return copy;
161 }
162 
163 /*
164  * Convert ASCII string to TCP/IP port number.
165  * Port must be >0 and <=65535.
166  * Return 0 if invalid.
167  */
168 int
169 a2port(const char *s)
170 {
171 	long port;
172 	char *endp;
173 
174 	errno = 0;
175 	port = strtol(s, &endp, 0);
176 	if (s == endp || *endp != '\0' ||
177 	    (errno == ERANGE && (port == LONG_MIN || port == LONG_MAX)) ||
178 	    port <= 0 || port > 65535)
179 		return 0;
180 
181 	return port;
182 }
183 
184 #define SECONDS		1
185 #define MINUTES		(SECONDS * 60)
186 #define HOURS		(MINUTES * 60)
187 #define DAYS		(HOURS * 24)
188 #define WEEKS		(DAYS * 7)
189 
190 /*
191  * Convert a time string into seconds; format is
192  * a sequence of:
193  *      time[qualifier]
194  *
195  * Valid time qualifiers are:
196  *      <none>  seconds
197  *      s|S     seconds
198  *      m|M     minutes
199  *      h|H     hours
200  *      d|D     days
201  *      w|W     weeks
202  *
203  * Examples:
204  *      90m     90 minutes
205  *      1h30m   90 minutes
206  *      2d      2 days
207  *      1w      1 week
208  *
209  * Return -1 if time string is invalid.
210  */
211 long
212 convtime(const char *s)
213 {
214 	long total, secs;
215 	const char *p;
216 	char *endp;
217 
218 	errno = 0;
219 	total = 0;
220 	p = s;
221 
222 	if (p == NULL || *p == '\0')
223 		return -1;
224 
225 	while (*p) {
226 		secs = strtol(p, &endp, 10);
227 		if (p == endp ||
228 		    (errno == ERANGE && (secs == LONG_MIN || secs == LONG_MAX)) ||
229 		    secs < 0)
230 			return -1;
231 
232 		switch (*endp++) {
233 		case '\0':
234 			endp--;
235 		case 's':
236 		case 'S':
237 			break;
238 		case 'm':
239 		case 'M':
240 			secs *= MINUTES;
241 			break;
242 		case 'h':
243 		case 'H':
244 			secs *= HOURS;
245 			break;
246 		case 'd':
247 		case 'D':
248 			secs *= DAYS;
249 			break;
250 		case 'w':
251 		case 'W':
252 			secs *= WEEKS;
253 			break;
254 		default:
255 			return -1;
256 		}
257 		total += secs;
258 		if (total < 0)
259 			return -1;
260 		p = endp;
261 	}
262 
263 	return total;
264 }
265 
266 char *
267 cleanhostname(char *host)
268 {
269 	if (*host == '[' && host[strlen(host) - 1] == ']') {
270 		host[strlen(host) - 1] = '\0';
271 		return (host + 1);
272 	} else
273 		return host;
274 }
275 
276 char *
277 colon(char *cp)
278 {
279 	int flag = 0;
280 
281 	if (*cp == ':')		/* Leading colon is part of file name. */
282 		return (0);
283 	if (*cp == '[')
284 		flag = 1;
285 
286 	for (; *cp; ++cp) {
287 		if (*cp == '@' && *(cp+1) == '[')
288 			flag = 1;
289 		if (*cp == ']' && *(cp+1) == ':' && flag)
290 			return (cp+1);
291 		if (*cp == ':' && !flag)
292 			return (cp);
293 		if (*cp == '/')
294 			return (0);
295 	}
296 	return (0);
297 }
298 
299 /* function to assist building execv() arguments */
300 void
301 addargs(arglist *args, char *fmt, ...)
302 {
303 	va_list ap;
304 	char buf[1024];
305 
306 	va_start(ap, fmt);
307 	vsnprintf(buf, sizeof(buf), fmt, ap);
308 	va_end(ap);
309 
310 	if (args->list == NULL) {
311 		args->nalloc = 32;
312 		args->num = 0;
313 	} else if (args->num+2 >= args->nalloc)
314 		args->nalloc *= 2;
315 
316 	args->list = xrealloc(args->list, args->nalloc * sizeof(char *));
317 	args->list[args->num++] = xstrdup(buf);
318 	args->list[args->num] = NULL;
319 }
320