xref: /freebsd/crypto/openssh/openbsd-compat/bsd-cygwin_util.c (revision f7c32ed617858bcd22f8d1b03199099d50125721)
1 /*
2  * Copyright (c) 2000, 2001, 2011, 2013 Corinna Vinschen <vinschen@redhat.com>
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  * Created: Sat Sep 02 12:17:00 2000 cv
25  *
26  * This file contains functions for forcing opened file descriptors to
27  * binary mode on Windows systems.
28  */
29 
30 #define NO_BINARY_OPEN	/* Avoid redefining open to binary_open for this file */
31 #include "includes.h"
32 
33 #ifdef HAVE_CYGWIN
34 
35 #include <sys/types.h>
36 #include <fcntl.h>
37 #include <string.h>
38 #include <unistd.h>
39 #include <stdarg.h>
40 #include <stdlib.h>
41 #include <wchar.h>
42 #include <wctype.h>
43 
44 #include "xmalloc.h"
45 
46 int
47 binary_open(const char *filename, int flags, ...)
48 {
49 	va_list ap;
50 	mode_t mode;
51 
52 	va_start(ap, flags);
53 	mode = va_arg(ap, mode_t);
54 	va_end(ap);
55 	return (open(filename, flags | O_BINARY, mode));
56 }
57 
58 int
59 check_ntsec(const char *filename)
60 {
61 	return (pathconf(filename, _PC_POSIX_PERMISSIONS));
62 }
63 
64 const char *
65 cygwin_ssh_privsep_user()
66 {
67   static char cyg_privsep_user[DNLEN + UNLEN + 2];
68 
69   if (!cyg_privsep_user[0])
70     {
71 #ifdef CW_CYGNAME_FROM_WINNAME
72       if (cygwin_internal (CW_CYGNAME_FROM_WINNAME, "sshd", cyg_privsep_user,
73 			   sizeof cyg_privsep_user) != 0)
74 #endif
75 	strlcpy(cyg_privsep_user, "sshd", sizeof(cyg_privsep_user));
76     }
77   return cyg_privsep_user;
78 }
79 
80 #define NL(x) x, (sizeof (x) - 1)
81 #define WENV_SIZ (sizeof (wenv_arr) / sizeof (wenv_arr[0]))
82 
83 static struct wenv {
84 	const char *name;
85 	size_t namelen;
86 } wenv_arr[] = {
87 	{ NL("ALLUSERSPROFILE=") },
88 	{ NL("COMPUTERNAME=") },
89 	{ NL("COMSPEC=") },
90 	{ NL("CYGWIN=") },
91 	{ NL("OS=") },
92 	{ NL("PATH=") },
93 	{ NL("PATHEXT=") },
94 	{ NL("PROGRAMFILES=") },
95 	{ NL("SYSTEMDRIVE=") },
96 	{ NL("SYSTEMROOT=") },
97 	{ NL("WINDIR=") }
98 };
99 
100 char **
101 fetch_windows_environment(void)
102 {
103 	char **e, **p;
104 	unsigned int i, idx = 0;
105 
106 	p = xcalloc(WENV_SIZ + 1, sizeof(char *));
107 	for (e = environ; *e != NULL; ++e) {
108 		for (i = 0; i < WENV_SIZ; ++i) {
109 			if (!strncmp(*e, wenv_arr[i].name, wenv_arr[i].namelen))
110 				p[idx++] = *e;
111 		}
112 	}
113 	p[idx] = NULL;
114 	return p;
115 }
116 
117 void
118 free_windows_environment(char **p)
119 {
120 	free(p);
121 }
122 
123 /*
124  * Returns true if the given string matches the pattern (which may contain ?
125  * and * as wildcards), and zero if it does not match.
126  *
127  * The Cygwin version of this function must be case-insensitive and take
128  * Unicode characters into account.
129  */
130 
131 static int
132 __match_pattern (const wchar_t *s, const wchar_t *pattern)
133 {
134 	for (;;) {
135 		/* If at end of pattern, accept if also at end of string. */
136 		if (!*pattern)
137 			return !*s;
138 
139 		if (*pattern == '*') {
140 			/* Skip the asterisk. */
141 			pattern++;
142 
143 			/* If at end of pattern, accept immediately. */
144 			if (!*pattern)
145 				return 1;
146 
147 			/* If next character in pattern is known, optimize. */
148 			if (*pattern != '?' && *pattern != '*') {
149 				/*
150 				 * Look instances of the next character in
151 				 * pattern, and try to match starting from
152 				 * those.
153 				 */
154 				for (; *s; s++)
155 					if (*s == *pattern &&
156 					    __match_pattern(s + 1, pattern + 1))
157 						return 1;
158 				/* Failed. */
159 				return 0;
160 			}
161 			/*
162 			 * Move ahead one character at a time and try to
163 			 * match at each position.
164 			 */
165 			for (; *s; s++)
166 				if (__match_pattern(s, pattern))
167 					return 1;
168 			/* Failed. */
169 			return 0;
170 		}
171 		/*
172 		 * There must be at least one more character in the string.
173 		 * If we are at the end, fail.
174 		 */
175 		if (!*s)
176 			return 0;
177 
178 		/* Check if the next character of the string is acceptable. */
179 		if (*pattern != '?' && towlower(*pattern) != towlower(*s))
180 			return 0;
181 
182 		/* Move to the next character, both in string and in pattern. */
183 		s++;
184 		pattern++;
185 	}
186 	/* NOTREACHED */
187 }
188 
189 static int
190 _match_pattern(const char *s, const char *pattern)
191 {
192 	wchar_t *ws;
193 	wchar_t *wpattern;
194 	size_t len;
195 	int ret;
196 
197 	if ((len = mbstowcs(NULL, s, 0)) < 0)
198 		return 0;
199 	ws = (wchar_t *) xcalloc(len + 1, sizeof (wchar_t));
200 	mbstowcs(ws, s, len + 1);
201 	if ((len = mbstowcs(NULL, pattern, 0)) < 0)
202 		return 0;
203 	wpattern = (wchar_t *) xcalloc(len + 1, sizeof (wchar_t));
204 	mbstowcs(wpattern, pattern, len + 1);
205 	ret = __match_pattern (ws, wpattern);
206 	free(ws);
207 	free(wpattern);
208 	return ret;
209 }
210 
211 /*
212  * Tries to match the string against the
213  * comma-separated sequence of subpatterns (each possibly preceded by ! to
214  * indicate negation).  Returns -1 if negation matches, 1 if there is
215  * a positive match, 0 if there is no match at all.
216  */
217 int
218 cygwin_ug_match_pattern_list(const char *string, const char *pattern)
219 {
220 	char sub[1024];
221 	int negated;
222 	int got_positive;
223 	u_int i, subi, len = strlen(pattern);
224 
225 	got_positive = 0;
226 	for (i = 0; i < len;) {
227 		/* Check if the subpattern is negated. */
228 		if (pattern[i] == '!') {
229 			negated = 1;
230 			i++;
231 		} else
232 			negated = 0;
233 
234 		/*
235 		 * Extract the subpattern up to a comma or end.  Convert the
236 		 * subpattern to lowercase.
237 		 */
238 		for (subi = 0;
239 		    i < len && subi < sizeof(sub) - 1 && pattern[i] != ',';
240 		    subi++, i++)
241 			sub[subi] = pattern[i];
242 		/* If subpattern too long, return failure (no match). */
243 		if (subi >= sizeof(sub) - 1)
244 			return 0;
245 
246 		/* If the subpattern was terminated by a comma, then skip it. */
247 		if (i < len && pattern[i] == ',')
248 			i++;
249 
250 		/* Null-terminate the subpattern. */
251 		sub[subi] = '\0';
252 
253 		/* Try to match the subpattern against the string. */
254 		if (_match_pattern(string, sub)) {
255 			if (negated)
256 				return -1;		/* Negative */
257 			else
258 				got_positive = 1;	/* Positive */
259 		}
260 	}
261 
262 	/*
263 	 * Return success if got a positive match.  If there was a negative
264 	 * match, we have already returned -1 and never get here.
265 	 */
266 	return got_positive;
267 }
268 
269 #endif /* HAVE_CYGWIN */
270