diff options
Diffstat (limited to 'sys/kern/imgact_shell.c')
| -rw-r--r-- | sys/kern/imgact_shell.c | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/sys/kern/imgact_shell.c b/sys/kern/imgact_shell.c new file mode 100644 index 0000000..2884231 --- /dev/null +++ b/sys/kern/imgact_shell.c @@ -0,0 +1,145 @@ +/* + * 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. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by David Greenman + * 4. The name of the developer may be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * 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 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. + * + * $Id: imgact_shell.c,v 1.4 1994/08/13 03:50:23 wollman Exp $ + */ + +#include <sys/param.h> +#include <sys/systm.h> +#include <sys/resourcevar.h> +#include <sys/exec.h> +#include <sys/imgact.h> +#include <sys/kernel.h> +#include <machine/endian.h> + +#if BYTE_ORDER == LITTLE_ENDIAN +#define SHELLMAGIC 0x2123 /* #! */ +#else +#define SHELLMAGIC 0x2321 +#endif + +#define MAXSHELLCMDLEN 64 + +/* + * Shell interpreter image activator. A interpreter name beginning + * at iparams->stringbase is the minimal successful exit requirement. + */ +int +exec_shell_imgact(iparams) + struct image_params *iparams; +{ + const char *image_header = iparams->image_header; + const char *ihp, *line_endp; + int length; + char *interp; + char **argv; + + /* a shell script? */ + if (((short *) image_header)[0] != SHELLMAGIC) + return(-1); + + /* + * Don't allow a shell script to be the shell for a shell + * script. :-) + */ + if (iparams->interpreted) + return(ENOEXEC); + + iparams->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) { + if (ihp >= &image_header[MAXSHELLCMDLEN]) + return(ENOEXEC); + } + 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 = iparams->interpreter_name; + while ((ihp < line_endp) && (*ihp != ' ') && (*ihp != '\t')) + *interp++ = *ihp++; + *interp = '\0'; + + /* Disallow a null interpreter filename */ + if (*iparams->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')) { + *iparams->stringp++ = *ihp++; + iparams->stringspace--; + } + + *iparams->stringp++ = 0; + iparams->stringspace--; + + iparams->argc++; + } + } + + /* set argv[0] to point to original file name */ + suword(iparams->uap->argv, (int)iparams->uap->fname); + + return(0); +} + +/* + * Tell kern_execve.c about it, with a little help from the linker. + * Since `const' objects end up in the text segment, TEXT_SET is the + * correct directive to use. + */ +static const struct execsw shell_execsw = { exec_shell_imgact, "#!" }; +TEXT_SET(execsw_set, shell_execsw); |
