a5f75648d8
exceeds MAXSHELLCMDLEN to avoid secondary /bin/sh execution. Update execve man page to reflect change. Increase MAXSHELLCMDLEN to a slightly more meaningful value. PR: kern/32106 Submitted by: b@etek.chalmers.se Reviewed by: bsd MFC after: 2 weeks
133 lines
3.7 KiB
C
133 lines
3.7 KiB
C
/*
|
|
* Copyright (c) 1993, David Greenman
|
|
* 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 THE AUTHOR 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 AUTHOR 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.
|
|
*
|
|
* $FreeBSD$
|
|
*/
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/sysproto.h>
|
|
#include <sys/exec.h>
|
|
#include <sys/imgact.h>
|
|
#include <sys/kernel.h>
|
|
|
|
#if BYTE_ORDER == LITTLE_ENDIAN
|
|
#define SHELLMAGIC 0x2123 /* #! */
|
|
#else
|
|
#define SHELLMAGIC 0x2321
|
|
#endif
|
|
|
|
/*
|
|
* Shell interpreter image activator. A interpreter name beginning
|
|
* at imgp->stringbase is the minimal successful exit requirement.
|
|
*/
|
|
int
|
|
exec_shell_imgact(imgp)
|
|
struct image_params *imgp;
|
|
{
|
|
const char *image_header = imgp->image_header;
|
|
const char *ihp, *line_endp;
|
|
char *interp;
|
|
|
|
/* a shell script? */
|
|
if (((const short *) image_header)[0] != SHELLMAGIC)
|
|
return(-1);
|
|
|
|
/*
|
|
* Don't allow a shell script to be the shell for a shell
|
|
* script. :-)
|
|
*/
|
|
if (imgp->interpreted)
|
|
return(ENOEXEC);
|
|
|
|
imgp->interpreted = 1;
|
|
|
|
/*
|
|
* Copy shell name and arguments from image_header into string
|
|
* buffer.
|
|
*/
|
|
|
|
/*
|
|
* Find end of line; return if the line > MAXSHELLCMDLEN long.
|
|
*/
|
|
for (ihp = &image_header[2]; *ihp != '\n' && *ihp != '#'; ++ihp) {
|
|
if (ihp >= &image_header[MAXSHELLCMDLEN])
|
|
return(ENAMETOOLONG);
|
|
}
|
|
line_endp = ihp;
|
|
|
|
/* reset for another pass */
|
|
ihp = &image_header[2];
|
|
|
|
/* Skip over leading spaces - until the interpreter name */
|
|
while ((*ihp == ' ') || (*ihp == '\t')) ihp++;
|
|
|
|
/* copy the interpreter name */
|
|
interp = imgp->interpreter_name;
|
|
while ((ihp < line_endp) && (*ihp != ' ') && (*ihp != '\t'))
|
|
*interp++ = *ihp++;
|
|
*interp = '\0';
|
|
|
|
/* Disallow a null interpreter filename */
|
|
if (*imgp->interpreter_name == '\0')
|
|
return(ENOEXEC);
|
|
|
|
/* reset for another pass */
|
|
ihp = &image_header[2];
|
|
|
|
/* copy the interpreter name and arguments */
|
|
while (ihp < line_endp) {
|
|
/* Skip over leading spaces */
|
|
while ((*ihp == ' ') || (*ihp == '\t')) ihp++;
|
|
|
|
if (ihp < line_endp) {
|
|
/*
|
|
* Copy to end of token. No need to watch stringspace
|
|
* because this is at the front of the string buffer
|
|
* and the maximum shell command length is tiny.
|
|
*/
|
|
while ((ihp < line_endp) && (*ihp != ' ') && (*ihp != '\t')) {
|
|
*imgp->stringp++ = *ihp++;
|
|
imgp->stringspace--;
|
|
}
|
|
|
|
*imgp->stringp++ = 0;
|
|
imgp->stringspace--;
|
|
|
|
imgp->argc++;
|
|
}
|
|
}
|
|
|
|
imgp->argv0 = imgp->uap->fname;
|
|
|
|
return(0);
|
|
}
|
|
|
|
/*
|
|
* Tell kern_execve.c about it, with a little help from the linker.
|
|
*/
|
|
static struct execsw shell_execsw = { exec_shell_imgact, "#!" };
|
|
EXEC_SET(shell, shell_execsw);
|