/*-
* Copyright (c) 2005-2010
* Jeffrey Allen Neitzel <jan (at) v6shell (dot) org>.
* 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.
*
* THIS SOFTWARE IS PROVIDED BY JEFFREY ALLEN NEITZEL ``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 JEFFREY ALLEN NEITZEL 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.
*
* @(#)$Id$
*/
/*
* Derived from:
* - /usr/src/lib/libc/gen/execvp.c:
* $NetBSD: execvp.c,v 1.24 2003/08/07 16:42:47 agc 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.
*
* @(#)exec.c 8.1 (Berkeley) 6/4/93
*/
#include "defs.h"
#include "err.h"
#include "pexec.h"
extern char **environ;
/*
* Execute a file or path name.
*/
int
pexec(const char *file, char *const *argv)
{
const char **esh_argv;
size_t dlen, flen;
int cnt, eacces = 0;
const char *d, *esh, *f, *pnp, *upp;
char pnbuf[PATHMAX];
/*
* Fail if the value of file, argv, or argv[0] is invalid.
*/
errno = 0;
if (file == NULL || argv == NULL || argv[0] == NULL) {
errno = EINVAL;
goto fail;
}
if (*file == EOS || *argv[0] == EOS)
goto fail;
flen = strlen(file);
/*
* If the name of the specified file contains one or more
* `/' characters, it is used as the path name to execute.
*/
for (f = file; *f != EOS; f++)
if (*f == SLASH) {
pnp = file;
upp = "";
goto exec_pathname;
}
*pnbuf = EOS;
pnp = pnbuf;
/*
* Get the user's PATH. Fail if PATH is unset or is
* set to the empty string, as no PATH search shall be
* performed in such a case.
*/
upp = getenv("PATH");
if (upp == NULL || *upp == EOS)
goto fail;
do {
/* Find the end of this PATH element. */
for (d = upp; *upp != COLON && *upp != EOS; upp++)
; /* nothing */
/*
* Since this is a shell PATH, double, leading, and/or
* trailing colons indicate the current directory.
*/
if (d == upp) {
d = ".";
dlen = 1;
} else
dlen = (size_t)(upp - d);
/*
* Complain if this path name for file would be too long.
* Otherwise, use this PATH element to build a possible
* path name for file. Then, attempt to execve(2) it.
*/
if (dlen + flen + 1 >= sizeof(pnbuf)) {
struct iovec msg[3];
msg[0].iov_base = (char *)"pexec: ";
msg[0].iov_len = (size_t)7;
msg[1].iov_base = (char *)d;
msg[1].iov_len = dlen;
msg[2].iov_base = (char *)": path too long\n";
msg[2].iov_len = (size_t)16;
(void)writev(FD2, msg, 3);
continue;
}
(void)memcpy(pnbuf, d, dlen);
pnbuf[dlen] = SLASH;
(void)memcpy(pnbuf + dlen + 1, file, flen);
pnbuf[dlen + flen + 1] = EOS;
exec_pathname:
(void)execve(pnp, argv, environ);
switch (errno) {
case EACCES:
#if defined(__OpenBSD__)
case EISDIR: /* Treat it as an EACCES error. */
#endif
eacces = 1;
/*FALLTHROUGH*/
case ELOOP:
case ENAMETOOLONG:
case ENOENT:
case ENOTDIR:
break;
case ENOEXEC:
/*
* Get the user's EXECSHELL.
* Fail if it is unset or is set to an unusable value.
*/
esh = getenv("EXECSHELL");
if (esh==NULL||*esh==EOS||strlen(esh)>=sizeof(pnbuf))
goto fail;
for (cnt = 0; argv[cnt] != NULL; cnt++)
; /* nothing */
esh_argv = malloc((cnt + 2) * sizeof(char *));
if (esh_argv == NULL)
goto fail;
esh_argv[0] = esh;
esh_argv[1] = pnp;
(void)memcpy(&esh_argv[2],&argv[1],cnt*sizeof(char *));
(void)execve(esh, (char *const *)esh_argv, environ);
free(esh_argv);
errno = (errno == E2BIG) ? E2BIG : ENOEXEC;
/*FALLTHROUGH*/
default:
goto fail;
}
} while (*upp++ == COLON); /* Otherwise, *upp was NUL. */
if (eacces != 0)
errno = EACCES;
fail:
if (errno == 0)
errno = ENOENT;
return -1;
}
/*
* Execute a file or path name w/ error handling.
* This function never returns.
*/
void
err_pexec(const char *file, char *const *argv)
{
const char *f, *n;
(void)pexec(file, argv);
f = (file == NULL) ? "(null)" : file;
n = getmyname();
if (errno == ENOEXEC) err(125,FMT3S,n,f,ERR_NOSHELL);
if (errno == E2BIG) err(126,FMT3S,n,f,ERR_E2BIG);
if (errno != ENOENT && errno != ENOTDIR) err(126,FMT3S,n,f,ERR_EXEC);
err(127,FMT3S,n,f,ERR_NOTFOUND);
}
