xref: /titanic_41/usr/src/cmd/ssh/libopenbsd-compat/common/mktemp.c (revision 4a6ec905b96eb96a398c346f59e034a90ce8ad37)
1 /* THIS FILE HAS BEEN MODIFIED FROM THE ORIGINAL OPENBSD SOURCE */
2 /* Changes: Removed mktemp */
3 
4 /*
5  * Copyright (c) 1987, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #include "includes.h"
38 
39 #ifndef HAVE_MKDTEMP
40 
41 #if defined(LIBC_SCCS) && !defined(lint)
42 static char rcsid[] = "$OpenBSD: mktemp.c,v 1.16 2002/05/27 18:20:45 millert Exp $";
43 #endif /* LIBC_SCCS and not lint */
44 
45 #ifdef HAVE_CYGWIN
46 #define open binary_open
47 extern int binary_open();
48 #endif
49 
50 static int _gettemp(char *, int *, int, int);
51 
52 int
53 mkstemps(path, slen)
54 	char *path;
55 	int slen;
56 {
57 	int fd;
58 
59 	return (_gettemp(path, &fd, 0, slen) ? fd : -1);
60 }
61 
62 int
63 mkstemp(path)
64 	char *path;
65 {
66 	int fd;
67 
68 	return (_gettemp(path, &fd, 0, 0) ? fd : -1);
69 }
70 
71 char *
72 mkdtemp(path)
73 	char *path;
74 {
75 	return(_gettemp(path, (int *)NULL, 1, 0) ? path : (char *)NULL);
76 }
77 
78 static int
79 _gettemp(path, doopen, domkdir, slen)
80 	char *path;
81 	register int *doopen;
82 	int domkdir;
83 	int slen;
84 {
85 	register char *start, *trv, *suffp;
86 	struct stat sbuf;
87 	int rval;
88 	pid_t pid;
89 
90 	if (doopen && domkdir) {
91 		errno = EINVAL;
92 		return(0);
93 	}
94 
95 	for (trv = path; *trv; ++trv)
96 		;
97 	trv -= slen;
98 	suffp = trv;
99 	--trv;
100 	if (trv < path) {
101 		errno = EINVAL;
102 		return (0);
103 	}
104 	pid = getpid();
105 	while (trv >= path && *trv == 'X' && pid != 0) {
106 		*trv-- = (pid % 10) + '0';
107 		pid /= 10;
108 	}
109 	while (trv >= path && *trv == 'X') {
110 		char c;
111 
112 		pid = (arc4random() & 0xffff) % (26+26);
113 		if (pid < 26)
114 			c = pid + 'A';
115 		else
116 			c = (pid - 26) + 'a';
117 		*trv-- = c;
118 	}
119 	start = trv + 1;
120 
121 	/*
122 	 * check the target directory; if you have six X's and it
123 	 * doesn't exist this runs for a *very* long time.
124 	 */
125 	if (doopen || domkdir) {
126 		for (;; --trv) {
127 			if (trv <= path)
128 				break;
129 			if (*trv == '/') {
130 				*trv = '\0';
131 				rval = stat(path, &sbuf);
132 				*trv = '/';
133 				if (rval != 0)
134 					return(0);
135 				if (!S_ISDIR(sbuf.st_mode)) {
136 					errno = ENOTDIR;
137 					return(0);
138 				}
139 				break;
140 			}
141 		}
142 	}
143 
144 	for (;;) {
145 		if (doopen) {
146 			if ((*doopen =
147 			    open(path, O_CREAT|O_EXCL|O_RDWR, 0600)) >= 0)
148 				return(1);
149 			if (errno != EEXIST)
150 				return(0);
151 		} else if (domkdir) {
152 			if (mkdir(path, 0700) == 0)
153 				return(1);
154 			if (errno != EEXIST)
155 				return(0);
156 		} else if (lstat(path, &sbuf))
157 			return(errno == ENOENT ? 1 : 0);
158 
159 		/* tricky little algorithm for backward compatibility */
160 		for (trv = start;;) {
161 			if (!*trv)
162 				return (0);
163 			if (*trv == 'Z') {
164 				if (trv == suffp)
165 					return (0);
166 				*trv++ = 'a';
167 			} else {
168 				if (isdigit(*trv))
169 					*trv = 'a';
170 				else if (*trv == 'z')	/* inc from z to A */
171 					*trv = 'A';
172 				else {
173 					if (trv == suffp)
174 						return (0);
175 					++*trv;
176 				}
177 				break;
178 			}
179 		}
180 	}
181 	/*NOTREACHED*/
182 }
183 
184 #endif /* !HAVE_MKDTEMP */
185 
186 #pragma ident	"%Z%%M%	%I%	%E% SMI"
187