1 /*-------------------------------------------------------------------------
2 *
3 * mkdtemp.c
4 * create a mode-0700 temporary directory
5 *
6 * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
7 *
8 *
9 * IDENTIFICATION
10 * src/port/mkdtemp.c
11 *
12 * This code was taken from NetBSD to provide an implementation for platforms
13 * that lack it. (Among compatibly-licensed implementations, the OpenBSD
14 * version better resists denial-of-service attacks. However, it has a
15 * cryptographic dependency.) The NetBSD copyright terms follow.
16 *-------------------------------------------------------------------------
17 */
18
19 #include "c.h"
20
21 #define _DIAGASSERT(x) do {} while (0)
22
23
24 /* $NetBSD: gettemp.c,v 1.17 2014/01/21 19:09:48 seanb Exp $ */
25
26 /*
27 * Copyright (c) 1987, 1993
28 * The Regents of the University of California. All rights reserved.
29 *
30 * Redistribution and use in source and binary forms, with or without
31 * modification, are permitted provided that the following conditions
32 * are met:
33 * 1. Redistributions of source code must retain the above copyright
34 * notice, this list of conditions and the following disclaimer.
35 * 2. Redistributions in binary form must reproduce the above copyright
36 * notice, this list of conditions and the following disclaimer in the
37 * documentation and/or other materials provided with the distribution.
38 * 3. Neither the name of the University nor the names of its contributors
39 * may be used to endorse or promote products derived from this software
40 * without specific prior written permission.
41 *
42 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
43 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
44 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
45 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
46 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
47 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
48 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
49 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
50 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
51 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
52 * SUCH DAMAGE.
53 */
54
55 #if HAVE_NBTOOL_CONFIG_H
56 #include "nbtool_config.h"
57 #endif
58
59 #if !HAVE_NBTOOL_CONFIG_H || !HAVE_MKSTEMP || !HAVE_MKDTEMP
60
61 #ifdef NOT_POSTGRESQL
62 #include <sys/cdefs.h>
63 #if defined(LIBC_SCCS) && !defined(lint)
64 #if 0
65 static char sccsid[] = "@(#)mktemp.c 8.1 (Berkeley) 6/4/93";
66 #else
67 __RCSID("$NetBSD: gettemp.c,v 1.17 2014/01/21 19:09:48 seanb Exp $");
68 #endif
69 #endif /* LIBC_SCCS and not lint */
70 #endif
71
72 #include <sys/types.h>
73 #include <sys/stat.h>
74
75 #include <assert.h>
76 #include <ctype.h>
77 #include <errno.h>
78 #include <fcntl.h>
79 #include <stdio.h>
80 #include <stdlib.h>
81 #include <unistd.h>
82
83 #ifdef NOT_POSTGRESQL
84 #if HAVE_NBTOOL_CONFIG_H
85 #define GETTEMP __nbcompat_gettemp
86 #else
87 #include "reentrant.h"
88 #include "local.h"
89 #define GETTEMP __gettemp
90 #endif
91 #endif
92
93 static int
GETTEMP(char * path,int * doopen,int domkdir)94 GETTEMP(char *path, int *doopen, int domkdir)
95 {
96 char *start,
97 *trv;
98 struct stat sbuf;
99 u_int pid;
100
101 /*
102 * To guarantee multiple calls generate unique names even if the file is
103 * not created. 676 different possibilities with 7 or more X's, 26 with 6
104 * or less.
105 */
106 static char xtra[2] = "aa";
107 int xcnt = 0;
108
109 _DIAGASSERT(path != NULL);
110 /* doopen may be NULL */
111
112 pid = getpid();
113
114 /* Move to end of path and count trailing X's. */
115 for (trv = path; *trv; ++trv)
116 if (*trv == 'X')
117 xcnt++;
118 else
119 xcnt = 0;
120
121 /* Use at least one from xtra. Use 2 if more than 6 X's. */
122 if (xcnt > 0)
123 {
124 *--trv = xtra[0];
125 xcnt--;
126 }
127 if (xcnt > 5)
128 {
129 *--trv = xtra[1];
130 xcnt--;
131 }
132
133 /* Set remaining X's to pid digits with 0's to the left. */
134 for (; xcnt > 0; xcnt--)
135 {
136 *--trv = (pid % 10) + '0';
137 pid /= 10;
138 }
139
140 /* update xtra for next call. */
141 if (xtra[0] != 'z')
142 xtra[0]++;
143 else
144 {
145 xtra[0] = 'a';
146 if (xtra[1] != 'z')
147 xtra[1]++;
148 else
149 xtra[1] = 'a';
150 }
151
152 /*
153 * check the target directory; if you have six X's and it doesn't exist
154 * this runs for a *very* long time.
155 */
156 for (start = trv + 1;; --trv)
157 {
158 if (trv <= path)
159 break;
160 if (*trv == '/')
161 {
162 int e;
163
164 *trv = '\0';
165 e = stat(path, &sbuf);
166 *trv = '/';
167 if (e == -1)
168 return doopen == NULL && !domkdir;
169 if (!S_ISDIR(sbuf.st_mode))
170 {
171 errno = ENOTDIR;
172 return doopen == NULL && !domkdir;
173 }
174 break;
175 }
176 }
177
178 for (;;)
179 {
180 if (doopen)
181 {
182 if ((*doopen =
183 open(path, O_CREAT | O_EXCL | O_RDWR, 0600)) >= 0)
184 return 1;
185 if (errno != EEXIST)
186 return 0;
187 }
188 else if (domkdir)
189 {
190 if (mkdir(path, 0700) >= 0)
191 return 1;
192 if (errno != EEXIST)
193 return 0;
194 }
195 else if (lstat(path, &sbuf))
196 return errno == ENOENT ? 1 : 0;
197
198 /* tricky little algorithm for backward compatibility */
199 for (trv = start;;)
200 {
201 if (!*trv)
202 return 0;
203 if (*trv == 'z')
204 *trv++ = 'a';
205 else
206 {
207 if (isdigit((unsigned char) *trv))
208 *trv = 'a';
209 else
210 ++*trv;
211 break;
212 }
213 }
214 }
215 /* NOTREACHED */
216 }
217
218 #endif /* !HAVE_NBTOOL_CONFIG_H || !HAVE_MKSTEMP ||
219 * !HAVE_MKDTEMP */
220
221
222 /* $NetBSD: mkdtemp.c,v 1.11 2012/03/15 18:22:30 christos Exp $ */
223
224 /*
225 * Copyright (c) 1987, 1993
226 * The Regents of the University of California. All rights reserved.
227 *
228 * Redistribution and use in source and binary forms, with or without
229 * modification, are permitted provided that the following conditions
230 * are met:
231 * 1. Redistributions of source code must retain the above copyright
232 * notice, this list of conditions and the following disclaimer.
233 * 2. Redistributions in binary form must reproduce the above copyright
234 * notice, this list of conditions and the following disclaimer in the
235 * documentation and/or other materials provided with the distribution.
236 * 3. Neither the name of the University nor the names of its contributors
237 * may be used to endorse or promote products derived from this software
238 * without specific prior written permission.
239 *
240 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
241 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
242 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
243 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
244 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
245 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
246 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
247 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
248 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
249 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
250 * SUCH DAMAGE.
251 */
252
253 #if HAVE_NBTOOL_CONFIG_H
254 #include "nbtool_config.h"
255 #endif
256
257 #if !HAVE_NBTOOL_CONFIG_H || !HAVE_MKDTEMP
258
259 #ifdef NOT_POSTGRESQL
260
261 #include <sys/cdefs.h>
262 #if defined(LIBC_SCCS) && !defined(lint)
263 #if 0
264 static char sccsid[] = "@(#)mktemp.c 8.1 (Berkeley) 6/4/93";
265 #else
266 __RCSID("$NetBSD: mkdtemp.c,v 1.11 2012/03/15 18:22:30 christos Exp $");
267 #endif
268 #endif /* LIBC_SCCS and not lint */
269
270 #if HAVE_NBTOOL_CONFIG_H
271 #define GETTEMP __nbcompat_gettemp
272 #else
273 #include <assert.h>
274 #include <errno.h>
275 #include <stdio.h>
276 #include <stdlib.h>
277 #include <unistd.h>
278 #include "reentrant.h"
279 #include "local.h"
280 #define GETTEMP __gettemp
281 #endif
282
283 #endif
284
285 char *
mkdtemp(char * path)286 mkdtemp(char *path)
287 {
288 _DIAGASSERT(path != NULL);
289
290 return GETTEMP(path, NULL, 1) ? path : NULL;
291 }
292
293 #endif /* !HAVE_NBTOOL_CONFIG_H || !HAVE_MKDTEMP */
294