/*--------------------------------------------------------------------*/
/*--- User-mode execve() for #! scripts. m_ume_script.c ---*/
/*--------------------------------------------------------------------*/
/*
This file is part of Valgrind, a dynamic binary instrumentation
framework.
Copyright (C) 2000-2013 Julian Seward
jseward@acm.org
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307, USA.
The GNU General Public License is contained in the file COPYING.
*/
#include "pub_core_basics.h"
#include "pub_core_vki.h"
#include "pub_core_libcbase.h"
#include "pub_core_libcassert.h" // VG_(exit), vg_assert
#include "pub_core_libcfile.h" // VG_(close) et al
#include "pub_core_libcprint.h"
#include "pub_core_clientstate.h" // VG_(args_the_exename)
#include "pub_core_mallocfree.h" // VG_(strdup)
#include "pub_core_ume.h" // self
#include "priv_ume.h"
Bool VG_(match_script)(const void *hdr, SizeT len)
{
const HChar* script = hdr;
const HChar* end = script + len;
const HChar* interp = script + 2;
// len < 4: need '#', '!', plus at least a '/' and one more char
if (len < 4) return False;
if (0 != VG_(memcmp)(hdr, "#!", 2)) return False;
// Find interpreter name, make sure it's an absolute path (starts with
// '/') and has at least one more char. First, skip over any space
// between the #! and the start of the interpreter name
while (interp < end && (*interp == ' ' || *interp == '\t')) interp++;
// overrun?
if (interp >= end) return False; // can't find start of interp name
// interp should now point at the /
if (*interp != '/') return False; // absolute path only for interpreter
// check for something plausible after the /
interp++;
if (interp >= end) return False;
if (VG_(isspace)(*interp)) return False;
// Here we should get the full interpreter name and check it with
// check_executable(). See the "EXEC FAILED" failure when running shell
// for an example.
return True; // looks like a #! script
}
/* returns: 0 = success, non-0 is failure */
Int VG_(load_script)(Int fd, const HChar* name, ExeInfo* info)
{
HChar hdr[4096];
Int len = sizeof hdr;
Int eol;
HChar* interp;
HChar* end;
HChar* cp;
HChar* arg = NULL;
SysRes res;
// Read the first part of the file.
res = VG_(pread)(fd, hdr, len, 0);
if (sr_isError(res)) {
VG_(close)(fd);
return VKI_EACCES;
} else {
len = sr_Res(res);
}
vg_assert('#' == hdr[0] && '!' == hdr[1]);
end = hdr + len;
interp = hdr + 2;
while (interp < end && (*interp == ' ' || *interp == '\t'))
interp++;
vg_assert(*interp == '/'); /* absolute path only for interpreter */
/* skip over interpreter name */
for (cp = interp; cp < end && !VG_(isspace)(*cp); cp++)
;
eol = (*cp == '\n');
*cp++ = '\0';
if (!eol && cp < end) {
/* skip space before arg */
while (cp < end && VG_(isspace)(*cp) && *cp != '\n')
cp++;
/* arg is from here to eol */
arg = cp;
while (cp < end && *cp != '\n')
cp++;
*cp = '\0';
}
info->interp_name = VG_(strdup)("ume.ls.1", interp);
vg_assert(NULL != info->interp_name);
if (arg != NULL && *arg != '\0') {
info->interp_args = VG_(strdup)("ume.ls.2", arg);
vg_assert(NULL != info->interp_args);
}
if (info->argv && info->argv[0] != NULL)
info->argv[0] = name;
VG_(args_the_exename) = name;
if (0)
VG_(printf)("#! script: interp_name=\"%s\" interp_args=\"%s\"\n",
info->interp_name, info->interp_args);
return VG_(do_exec_inner)(interp, info);
}
/*--------------------------------------------------------------------*/
/*--- end ---*/
/*--------------------------------------------------------------------*/