/* ====================================================================
* The Apache Software License, Version 1.1
*
* Copyright (c) 2000 The Apache Software Foundation. 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. The end-user documentation included with the redistribution,
* if any, must include the following acknowledgment:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgment may appear in the software itself,
* if and wherever such third-party acknowledgments normally appear.
*
* 4. The names "Apache" and "Apache Software Foundation" must
* not be used to endorse or promote products derived from this
* software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache",
* nor may "Apache" appear in their name, without prior written
* permission of the Apache Software Foundation.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED 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 APACHE SOFTWARE FOUNDATION OR
* ITS 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.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*
* Portions of this software are based upon public domain software
* originally written at the National Center for Supercomputing Applications,
* University of Illinois, Urbana-Champaign.
*/
/*
* Portions of this code are under this license:
*
* Copyright (c) 1980, 1991 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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 "httpd.h"
/*---------------------------------------------------------------*/
#ifdef NEED_HASHBANG_EMUL
#undef execle
#undef execve
static const char **hashbang(const char *filename, char * const *argv);
/* Historically, a list of arguments on the stack was often treated as
* being equivalent to an array (since they already were "contiguous"
* on the stack, and the arguments were pushed in the correct order).
* On today's processors, this is not necessarily equivalent, because
* often arguments are padded or passed partially in registers,
* or the stack direction is backwards.
* To be on the safe side, we copy the argument list to our own
* local argv[] array. The va_arg logic makes sure we do the right thing.
* XXX: malloc() is used because we expect to be overlaid soon.
*/
int ap_execle(const char *filename, const char *argv0, ...)
{
va_list adummy;
char **envp;
char **argv;
int argc, ret;
/* First pass: Count arguments on stack */
va_start(adummy, argv0);
for (argc = 1; va_arg(adummy, char *) != NULL; ++argc) {
continue;
}
va_end(adummy);
if ((argv = (char **) malloc((argc + 2) * sizeof(*argv))) == NULL) {
fprintf(stderr, "Ouch! Out of memory in ap_execle()!\n");
return -1;
}
/* Pass two --- copy the argument strings into the result space */
va_start(adummy, argv0);
argv[0] = (char *)argv0;
for (argc = 1; (argv[argc] = va_arg(adummy, char *)) != NULL; ++argc) {
continue;
}
envp = va_arg(adummy, char **);
va_end(adummy);
ret = ap_execve(filename, argv, envp);
free(argv);
return ret;
}
/* Count number of entries in vector "args", including the trailing NULL entry
*/
static int
count_args(char * const *args)
{
int i;
for (i = 0; args[i] != NULL; ++i) {
continue;
}
return i+1;
}
/* Emulate the execve call, respecting a #!/interpreter line if present.
* On "real" unixes, the kernel does this.
* We have to fiddle with the argv array to make it work on platforms
* which don't support the "hashbang" interpreter line by default.
*/
int ap_execve(const char *filename, char * const argv[],
char * const envp[])
{
char **script_argv;
extern char **environ;
if (envp == NULL) {
envp = (char * const *) environ;
}
/* Try to execute the file directly first: */
execve(filename, argv, envp);
/* Still with us? Then something went seriously wrong.
* From the (linux) man page:
* EACCES The file is not a regular file.
* EACCES Execute permission is denied for the file.
* EACCES Search permission is denied on a component of the path prefix.
* EPERM The file system is mounted noexec.
* EPERM The file system is mounted nosuid and the file has an SUID
* or SGID bit set.
* E2BIG The argument list is too big.
* ENOEXEC The magic number in the file is incorrect.
* EFAULT filename points outside your accessible address space.
* ENAMETOOLONG filename is too long.
* ENOENT The file does not exist.
* ENOMEM Insufficient kernel memory was available.
* ENOTDIR A component of the path prefix is not a directory.
* ELOOP filename contains a circular reference (i.e., via a symbolic link)
*/
if (errno == ENOEXEC) {
/* Probably a script.
* Have a look; if there's a "#!" header then try to emulate
* the feature found in all modern OS's:
* Interpret the line following the #! as a command line
* in shell style.
*/
if ((script_argv = (char **)hashbang(filename, argv)) != NULL) {
/* new filename is the interpreter to call */
filename = script_argv[0];
/* Restore argv[0] as on entry */
if (argv[0] != NULL) {
script_argv[0] = argv[0];
}
execve(filename, script_argv, envp);
free(script_argv);
}
/*
* Script doesn't start with a hashbang line!
* So, try to have the default shell execute it.
* For this, the size of argv must be increased by one
* entry: the shell's name. The remaining args are appended.
*/
else {
int i = count_args(argv) + 1; /* +1 for leading SHELL_PATH */
if ((script_argv = malloc(sizeof(*script_argv) * i)) == NULL) {
fprintf(stderr, "Ouch! Out of memory in ap_execve()!\n");
return -1;
}
script_argv[0] = SHELL_PATH;
while (i > 0) {
script_argv[i] = argv[i-1];
--i;
}
execve(SHELL_PATH, script_argv, envp);
free(script_argv);
}
}
return -1;
}
/*---------------------------------------------------------------*/
/*
* From: peter@zeus.dialix.oz.au (Peter Wemm)
* (taken from tcsh)
* If exec() fails look first for a #! [word] [word] ....
* If it is, splice the header into the argument list and retry.
* Return value: the original argv array (sans argv[0]), with the
* script's argument list prepended.
* XXX: malloc() is used so that everything can be free()ed after a failure.
*/
#define HACKBUFSZ 1024 /* Max chars in #! vector */
#define HACKVECSZ 128 /* Max words in #! vector */
static const char **hashbang(const char *filename, char * const *argv)
{
char lbuf[HACKBUFSZ];
char *sargv[HACKVECSZ];
const char **newargv;
char *p, *ws;
int fd;
int sargc = 0;
int i, j;
#ifdef WIN32
int fw = 0; /* found at least one word */
int first_word = 0;
#endif /* WIN32 */
if ((fd = open(filename, O_RDONLY)) == -1) {
return NULL;
}
if (read(fd, (char *) lbuf, 2) != 2
|| lbuf[0] != '#' || lbuf[1] != '!'
|| read(fd, (char *) lbuf, HACKBUFSZ) <= 0) {
close(fd);
return NULL;
}
close(fd);
ws = NULL; /* word started = 0 */
for (p = lbuf; p < &lbuf[HACKBUFSZ];) {
switch (*p) {
case ' ':
case '\t':
#ifdef NEW_CRLF
case '\r':
#endif /*NEW_CRLF */
if (ws) { /* a blank after a word.. save it */
*p = '\0';
#ifndef WIN32
if (sargc < HACKVECSZ - 1) {
sargv[sargc++] = ws;
}
ws = NULL;
#else /* WIN32 */
if (sargc < HACKVECSZ - 1) {
sargv[sargc] = first_word ? NULL : hb_subst(ws);
if (sargv[sargc] == NULL) {
sargv[sargc] = ws;
}
sargc++;
}
ws = NULL;
fw = 1;
first_word = 1;
#endif /* WIN32 */
}
p++;
continue;
case '\0': /* Whoa!! what the hell happened */
return NULL;
case '\n': /* The end of the line. */
if (
#ifdef WIN32
fw ||
#endif /* WIN32 */
ws) { /* terminate the last word */
*p = '\0';
#ifndef WIN32
if (sargc < HACKVECSZ - 1) {
sargv[sargc++] = ws;
}
#else /* WIN32 */
if (sargc < HACKVECSZ - 1) { /* deal with the 1-word case */
sargv[sargc] = first_word ? NULL : hb_subst(ws);
if (sargv[sargc] == NULL) {
sargv[sargc] = ws;
}
sargc++;
}
#endif /* !WIN32 */
sargv[sargc] = NULL;
}
/* Count number of entries in the old argv vector */
for (i = 0; argv[i] != NULL; ++i) {
continue;
}
++i;
newargv = (const char **) malloc((p - lbuf + 1)
+ (i + sargc + 1) * sizeof(*newargv));
if (newargv == NULL) {
fprintf(stderr, "Ouch! Out of memory in hashbang()!\n");
return NULL;
}
ws = &((char *) newargv)[(i + sargc + 1) * sizeof(*newargv)];
/* Copy entries to allocated memory */
for (j = 0; j < sargc; ++j) {
newargv[j] = strcpy(ws, sargv[j]);
ws += strlen(ws) + 1; /* skip trailing '\0' */
}
newargv[sargc] = filename;
/* Append the old array. The old argv[0] is skipped. */
if (i > 1) {
memcpy(&newargv[sargc + 1], &argv[1],
(i - 1) * sizeof(*newargv));
}
newargv[sargc + i] = NULL;
ws = NULL;
return newargv;
default:
if (!ws) { /* Start a new word? */
ws = p;
}
p++;
break;
}
}
return NULL;
}
#else
extern void ap_execve_is_not_here(void);
void ap_execve_is_not_here(void) {}
#endif /* NEED_HASHBANG_EMUL */