1 files changed, 163 insertions, 0 deletions

diff --git a/src/lib/libc/stdlib/mktemp.c b/src/lib/libc/stdlib/mktemp.c
new file mode 100644
index 0000000000..3b8bba7846
--- /dev/null
+++ b/src/lib/libc/stdlib/mktemp.c
@@ -0,0 +1,163 @@
+/*      $OpenBSD: mktemp.c,v 1.1 2024/01/19 16:30:28 millert Exp $ */
+/*
+ * Copyright (c) 1996-1998, 2008 Theo de Raadt
+ * Copyright (c) 1997, 2008-2009 Todd C. Miller
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+#include <unistd.h>
+
+#define MKTEMP_NAME     0
+#define MKTEMP_FILE     1
+#define MKTEMP_DIR      2
+
+#define TEMPCHARS       "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"
+#define NUM_CHARS       (sizeof(TEMPCHARS) - 1)
+#define MIN_X           6
+
+#define MKOTEMP_FLAGS   (O_APPEND | O_CLOEXEC | O_DSYNC | O_RSYNC | O_SYNC)
+
+#ifndef nitems
+#define nitems(_a)      (sizeof((_a)) / sizeof((_a)[0]))
+#endif
+
+static int
+mktemp_internal(char *path, int slen, int mode, int flags)
+{
+        char *start, *cp, *ep;
+        const char tempchars[] = TEMPCHARS;
+        unsigned int tries;
+        struct stat sb;
+        size_t len;
+        int fd;
+
+        len = strlen(path);
+        if (len < MIN_X || slen < 0 || (size_t)slen > len - MIN_X) {
+                errno = EINVAL;
+                return(-1);
+        }
+        ep = path + len - slen;
+
+        for (start = ep; start > path && start[-1] == 'X'; start--)
+                ;
+        if (ep - start < MIN_X) {
+                errno = EINVAL;
+                return(-1);
+        }
+
+        if (flags & ~MKOTEMP_FLAGS) {
+                errno = EINVAL;
+                return(-1);
+        }
+        flags |= O_CREAT | O_EXCL | O_RDWR;
+
+        tries = INT_MAX;
+        do {
+                cp = start;
+                do {
+                        unsigned short rbuf[16];
+                        unsigned int i;
+
+                        /*
+                         * Avoid lots of arc4random() calls by using
+                         * a buffer sized for up to 16 Xs at a time.
+                         */
+                        arc4random_buf(rbuf, sizeof(rbuf));
+                        for (i = 0; i < nitems(rbuf) && cp != ep; i++)
+                                *cp++ = tempchars[rbuf[i] % NUM_CHARS];
+                } while (cp != ep);
+
+                switch (mode) {
+                case MKTEMP_NAME:
+                        if (lstat(path, &sb) != 0)
+                                return(errno == ENOENT ? 0 : -1);
+                        break;
+                case MKTEMP_FILE:
+                        fd = open(path, flags, S_IRUSR|S_IWUSR);
+                        if (fd != -1 || errno != EEXIST)
+                                return(fd);
+                        break;
+                case MKTEMP_DIR:
+                        if (mkdir(path, S_IRUSR|S_IWUSR|S_IXUSR) == 0)
+                                return(0);
+                        if (errno != EEXIST)
+                                return(-1);
+                        break;
+                }
+        } while (--tries);
+
+        errno = EEXIST;
+        return(-1);
+}
+
+char *
+_mktemp(char *path)
+{
+        if (mktemp_internal(path, 0, MKTEMP_NAME, 0) == -1)
+                return(NULL);
+        return(path);
+}
+
+__warn_references(mktemp,
+    "mktemp() possibly used unsafely; consider using mkstemp()");
+
+char *
+mktemp(char *path)
+{
+        return(_mktemp(path));
+}
+
+int
+mkostemps(char *path, int slen, int flags)
+{
+        return(mktemp_internal(path, slen, MKTEMP_FILE, flags));
+}
+
+int
+mkstemp(char *path)
+{
+        return(mktemp_internal(path, 0, MKTEMP_FILE, 0));
+}
+DEF_WEAK(mkstemp);
+
+int
+mkostemp(char *path, int flags)
+{
+        return(mktemp_internal(path, 0, MKTEMP_FILE, flags));
+}
+DEF_WEAK(mkostemp);
+
+int
+mkstemps(char *path, int slen)
+{
+        return(mktemp_internal(path, slen, MKTEMP_FILE, 0));
+}
+
+char *
+mkdtemp(char *path)
+{
+        int error;
+
+        error = mktemp_internal(path, 0, MKTEMP_DIR, 0);
+        return(error ? NULL : path);
+}