-/* $OpenBSD: exec.c,v 1.23 2016/03/13 18:34:20 guenther Exp $ */
-/*-
- * Copyright (c) 1991, 1993
- * The Regents of the University of California. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * 3. Neither the name of the University nor the names of its contributors
- * may be used to endorse or promote products derived from this software
- * without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- */
-
-#include "includes.h"
-
-#include <sys/types.h>
-#include <sys/uio.h>
-
-#include <errno.h>
-#include <limits.h>
-#include <paths.h>
-#include <stdarg.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-
-int
-execvpe(const char *name, char *const *argv, char *const *envp)
-{
- char **memp;
- int cnt;
- size_t lp, ln, len;
- char *p;
- int eacces = 0;
- char *bp, *cur, *path, buf[PATH_MAX];
-
- /*
- * Do not allow null name
- */
- if (name == NULL || *name == '\0') {
- errno = ENOENT;
- return (-1);
- }
-
- /* If it's an absolute or relative path name, it's easy. */
- if (strchr(name, '/')) {
- bp = (char *)name;
- cur = path = NULL;
- goto retry;
- }
- bp = buf;
-
- /* Get the path we're searching. */
- if (!(path = getenv("PATH")))
- path = _PATH_DEFPATH;
- len = strlen(path) + 1;
- cur = alloca(len);
- if (cur == NULL) {
- errno = ENOMEM;
- return (-1);
- }
- strlcpy(cur, path, len);
- path = cur;
- while ((p = strsep(&cur, ":"))) {
- /*
- * It's a SHELL path -- double, leading and trailing colons
- * mean the current directory.
- */
- if (!*p) {
- p = ".";
- lp = 1;
- } else
- lp = strlen(p);
- ln = strlen(name);
-
- /*
- * If the path is too long complain. This is a possible
- * security issue; given a way to make the path too long
- * the user may execute the wrong program.
- */
- if (lp + ln + 2 > sizeof(buf)) {
- struct iovec iov[3];
-
- iov[0].iov_base = "execvp: ";
- iov[0].iov_len = 8;
- iov[1].iov_base = p;
- iov[1].iov_len = lp;
- iov[2].iov_base = ": path too long\n";
- iov[2].iov_len = 16;
- (void)writev(STDERR_FILENO, iov, 3);
- continue;
- }
- bcopy(p, buf, lp);
- buf[lp] = '/';
- bcopy(name, buf + lp + 1, ln);
- buf[lp + ln + 1] = '\0';
-
-retry: (void)execve(bp, argv, envp);
- switch(errno) {
- case E2BIG:
- goto done;
- case EISDIR:
- case ELOOP:
- case ENAMETOOLONG:
- case ENOENT:
- break;
- case ENOEXEC:
- for (cnt = 0; argv[cnt]; ++cnt)
- ;
- memp = alloca((cnt + 2) * sizeof(char *));
- if (memp == NULL)
- goto done;
- memp[0] = "sh";
- memp[1] = bp;
- bcopy(argv + 1, memp + 2, cnt * sizeof(char *));
- (void)execve(_PATH_BSHELL, memp, envp);
- goto done;
- case ENOMEM:
- goto done;
- case ENOTDIR:
- break;
- case ETXTBSY:
- /*
- * We used to retry here, but sh(1) doesn't.
- */
- goto done;
- case EACCES:
- eacces = 1;
- break;
- default:
- goto done;
- }
- }
- if (eacces)
- errno = EACCES;
- else if (!errno)
- errno = ENOENT;
-done:
- return (-1);
-}