| |
| /*--------------------------------------------------------------------*/ |
| /*--- 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 ---*/ |
| /*--------------------------------------------------------------------*/ |