njn | 91772d1 | 2009-01-21 02:26:56 +0000 | [diff] [blame] | 1 | |
| 2 | /*--------------------------------------------------------------------*/ |
| 3 | /*--- User-mode execve() for #! scripts. m_ume_script.c ---*/ |
| 4 | /*--------------------------------------------------------------------*/ |
| 5 | |
| 6 | /* |
| 7 | This file is part of Valgrind, a dynamic binary instrumentation |
| 8 | framework. |
| 9 | |
njn | 9f20746 | 2009-03-10 22:02:09 +0000 | [diff] [blame] | 10 | Copyright (C) 2000-2009 Julian Seward |
njn | 91772d1 | 2009-01-21 02:26:56 +0000 | [diff] [blame] | 11 | jseward@acm.org |
| 12 | |
| 13 | This program is free software; you can redistribute it and/or |
| 14 | modify it under the terms of the GNU General Public License as |
| 15 | published by the Free Software Foundation; either version 2 of the |
| 16 | License, or (at your option) any later version. |
| 17 | |
| 18 | This program is distributed in the hope that it will be useful, but |
| 19 | WITHOUT ANY WARRANTY; without even the implied warranty of |
| 20 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 21 | General Public License for more details. |
| 22 | |
| 23 | You should have received a copy of the GNU General Public License |
| 24 | along with this program; if not, write to the Free Software |
| 25 | Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 26 | 02111-1307, USA. |
| 27 | |
| 28 | The GNU General Public License is contained in the file COPYING. |
| 29 | */ |
| 30 | |
| 31 | #include "pub_core_basics.h" |
| 32 | #include "pub_core_vki.h" |
| 33 | |
| 34 | #include "pub_core_libcbase.h" |
| 35 | #include "pub_core_libcassert.h" // VG_(exit), vg_assert |
| 36 | #include "pub_core_libcfile.h" // VG_(close) et al |
| 37 | #include "pub_core_libcprint.h" |
| 38 | #include "pub_core_mallocfree.h" // VG_(strdup) |
| 39 | #include "pub_core_ume.h" // self |
| 40 | |
| 41 | #include "priv_ume.h" // self |
| 42 | |
| 43 | |
| 44 | #if defined(HAVE_SCRIPT) |
| 45 | |
| 46 | Bool VG_(match_script)(Char *hdr, Int len) |
| 47 | { |
| 48 | Char* end = hdr + len; |
| 49 | Char* interp = hdr + 2; |
| 50 | |
| 51 | // len < 4: need '#', '!', plus at least a '/' and one more char |
| 52 | if (len < 4) return False; |
| 53 | if (0 != VG_(memcmp)(hdr, "#!", 2)) return False; |
| 54 | |
| 55 | // Find interpreter name, make sure it's an absolute path (starts with |
| 56 | // '/') and has at least one more char. First, skip over any space |
| 57 | // between the #! and the start of the interpreter name |
| 58 | while (interp < end && VG_(isspace)(*interp)) interp++; |
| 59 | |
| 60 | // overrun? |
| 61 | if (interp >= end) return False; // can't find start of interp name |
| 62 | |
| 63 | // interp should now point at the / |
| 64 | if (*interp != '/') return False; // absolute path only for interpreter |
| 65 | |
| 66 | // check for something plausible after the / |
| 67 | interp++; |
| 68 | if (interp >= end) return False; |
| 69 | if (VG_(isspace)(*interp)) return False; |
| 70 | |
| 71 | // Here we should get the full interpreter name and check it with |
| 72 | // check_executable(). See the "EXEC FAILED" failure when running shell |
| 73 | // for an example. |
| 74 | |
| 75 | return True; // looks like a #! script |
| 76 | } |
| 77 | |
| 78 | |
| 79 | /* returns: 0 = success, non-0 is failure */ |
| 80 | Int VG_(load_script)(Int fd, const HChar* name, ExeInfo* info) |
| 81 | { |
| 82 | Char hdr[4096]; |
| 83 | Int len = 4096; |
| 84 | Int eol; |
| 85 | Char* interp; |
| 86 | Char* end; |
| 87 | Char* cp; |
| 88 | Char* arg = NULL; |
| 89 | SysRes res; |
| 90 | |
| 91 | // Read the first part of the file. |
| 92 | res = VG_(pread)(fd, hdr, len, 0); |
njn | cda2f0f | 2009-05-18 02:12:08 +0000 | [diff] [blame^] | 93 | if (sr_isError(res)) { |
njn | 91772d1 | 2009-01-21 02:26:56 +0000 | [diff] [blame] | 94 | VG_(close)(fd); |
| 95 | return VKI_EACCES; |
| 96 | } else { |
njn | cda2f0f | 2009-05-18 02:12:08 +0000 | [diff] [blame^] | 97 | len = sr_Res(res); |
njn | 91772d1 | 2009-01-21 02:26:56 +0000 | [diff] [blame] | 98 | } |
| 99 | |
| 100 | vg_assert('#' == hdr[0] && '!' == hdr[1]); |
| 101 | |
| 102 | end = hdr + len; |
| 103 | interp = hdr + 2; |
| 104 | while (interp < end && VG_(isspace)(*interp)) |
| 105 | interp++; |
| 106 | |
| 107 | vg_assert(*interp == '/'); /* absolute path only for interpreter */ |
| 108 | |
| 109 | /* skip over interpreter name */ |
| 110 | for (cp = interp; cp < end && !VG_(isspace)(*cp); cp++) |
| 111 | ; |
| 112 | |
| 113 | eol = (*cp == '\n'); |
| 114 | |
| 115 | *cp++ = '\0'; |
| 116 | |
| 117 | if (!eol && cp < end) { |
| 118 | /* skip space before arg */ |
| 119 | while (cp < end && VG_(isspace)(*cp) && *cp != '\n') |
| 120 | cp++; |
| 121 | |
| 122 | /* arg is from here to eol */ |
| 123 | arg = cp; |
| 124 | while (cp < end && *cp != '\n') |
| 125 | cp++; |
| 126 | *cp = '\0'; |
| 127 | } |
| 128 | |
| 129 | info->interp_name = VG_(strdup)("ume.ls.1", interp); |
| 130 | vg_assert(NULL != info->interp_name); |
| 131 | if (arg != NULL && *arg != '\0') { |
| 132 | info->interp_args = VG_(strdup)("ume.ls.2", arg); |
| 133 | vg_assert(NULL != info->interp_args); |
| 134 | } |
| 135 | |
| 136 | if (info->argv && info->argv[0] != NULL) |
| 137 | info->argv[0] = (char *)name; |
| 138 | |
| 139 | if (0) |
| 140 | VG_(printf)("#! script: interp_name=\"%s\" interp_args=\"%s\"\n", |
| 141 | info->interp_name, info->interp_args); |
| 142 | |
| 143 | return VG_(do_exec_inner)(interp, info); |
| 144 | } |
| 145 | |
| 146 | #endif /* defined(HAVE_SCRIPT) */ |
| 147 | |
| 148 | /*--------------------------------------------------------------------*/ |
| 149 | /*--- end ---*/ |
| 150 | /*--------------------------------------------------------------------*/ |