1 /* THIS FILE HAS BEEN MODIFIED FROM THE ORIGINAL OPENBSD SOURCE */
2 /* Changes: Removed mktemp */
3
4 /* $OpenBSD: mktemp.c,v 1.30 2010/03/21 23:09:30 schwarze Exp $ */
5 /*
6 * Copyright (c) 1996-1998, 2008 Theo de Raadt
7 * Copyright (c) 1997, 2008-2009 Todd C. Miller
8 *
9 * Permission to use, copy, modify, and distribute this software for any
10 * purpose with or without fee is hereby granted, provided that the above
11 * copyright notice and this permission notice appear in all copies.
12 *
13 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
14 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
15 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
16 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
17 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
18 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
19 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
20 */
21
22 /* OPENBSD ORIGINAL: lib/libc/stdio/mktemp.c */
23
24 #include "includes.h"
25
26 #include <sys/types.h>
27 #include <sys/stat.h>
28 #include <errno.h>
29 #include <fcntl.h>
30 #include <limits.h>
31 #include <stdio.h>
32 #include <stdlib.h>
33 #include <string.h>
34 #include <ctype.h>
35 #include <unistd.h>
36
37 #ifdef mkstemp
38 #undef mkstemp
39 #endif
40 int mkstemp(char *);
41
42 /*
43 * From glibc man page: 'In glibc versions 2.06 and earlier, the file is
44 * created with permissions 0666, that is, read and write for all users.'
45 * Provide a wrapper to make sure the mask is reasonable (POSIX requires
46 * mode 0600, so mask off any other bits).
47 */
48 int
_ssh_mkstemp(char * template)49 _ssh_mkstemp(char *template)
50 {
51 mode_t mask;
52 int ret;
53
54 mask = umask(0177);
55 ret = mkstemp(template);
56 (void)umask(mask);
57 return ret;
58 }
59
60 #if !defined(HAVE_MKDTEMP)
61
62 #define MKTEMP_NAME 0
63 #define MKTEMP_FILE 1
64 #define MKTEMP_DIR 2
65
66 #define TEMPCHARS "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"
67 #define NUM_CHARS (sizeof(TEMPCHARS) - 1)
68
69 static int
mktemp_internal(char * path,int slen,int mode)70 mktemp_internal(char *path, int slen, int mode)
71 {
72 char *start, *cp, *ep;
73 const char *tempchars = TEMPCHARS;
74 unsigned int r, tries;
75 struct stat sb;
76 size_t len;
77 int fd;
78
79 len = strlen(path);
80 if (len == 0 || slen < 0 || (size_t)slen >= len) {
81 errno = EINVAL;
82 return(-1);
83 }
84 ep = path + len - slen;
85
86 tries = 1;
87 for (start = ep; start > path && start[-1] == 'X'; start--) {
88 if (tries < INT_MAX / NUM_CHARS)
89 tries *= NUM_CHARS;
90 }
91 tries *= 2;
92
93 do {
94 for (cp = start; cp != ep; cp++) {
95 r = arc4random_uniform(NUM_CHARS);
96 *cp = tempchars[r];
97 }
98
99 switch (mode) {
100 case MKTEMP_NAME:
101 if (lstat(path, &sb) != 0)
102 return(errno == ENOENT ? 0 : -1);
103 break;
104 case MKTEMP_FILE:
105 fd = open(path, O_CREAT|O_EXCL|O_RDWR, S_IRUSR|S_IWUSR);
106 if (fd != -1 || errno != EEXIST)
107 return(fd);
108 break;
109 case MKTEMP_DIR:
110 if (mkdir(path, S_IRUSR|S_IWUSR|S_IXUSR) == 0)
111 return(0);
112 if (errno != EEXIST)
113 return(-1);
114 break;
115 }
116 } while (--tries);
117
118 errno = EEXIST;
119 return(-1);
120 }
121
122 #if 0
123 char *_mktemp(char *);
124
125 char *
126 _mktemp(char *path)
127 {
128 if (mktemp_internal(path, 0, MKTEMP_NAME) == -1)
129 return(NULL);
130 return(path);
131 }
132
133 __warn_references(mktemp,
134 "warning: mktemp() possibly used unsafely; consider using mkstemp()");
135
136 char *
137 mktemp(char *path)
138 {
139 return(_mktemp(path));
140 }
141 #endif
142
143 int
mkstemp(char * path)144 mkstemp(char *path)
145 {
146 return(mktemp_internal(path, 0, MKTEMP_FILE));
147 }
148
149 int
mkstemps(char * path,int slen)150 mkstemps(char *path, int slen)
151 {
152 return(mktemp_internal(path, slen, MKTEMP_FILE));
153 }
154
155 char *
mkdtemp(char * path)156 mkdtemp(char *path)
157 {
158 int error;
159
160 error = mktemp_internal(path, 0, MKTEMP_DIR);
161 return(error ? NULL : path);
162 }
163
164 #endif /* !defined(HAVE_MKDTEMP) */
165