blob: ec473e9cb1eb0f0ef34bad61e7475de4423c4977
| 1 | /* vi: set sw=4 ts=4: */ |
| 2 | /* |
| 3 | * linux32/linux64 allows for changing uname emulation. |
| 4 | * |
| 5 | * Copyright 2002 Andi Kleen, SuSE Labs. |
| 6 | * |
| 7 | * Licensed under GPLv2 or later, see file LICENSE in this source tree. |
| 8 | */ |
| 9 | //config:config SETARCH |
| 10 | //config: bool "setarch" |
| 11 | //config: default y |
| 12 | //config: select PLATFORM_LINUX |
| 13 | //config: help |
| 14 | //config: The linux32 utility is used to create a 32bit environment for the |
| 15 | //config: specified program (usually a shell). It only makes sense to have |
| 16 | //config: this util on a system that supports both 64bit and 32bit userland |
| 17 | //config: (like amd64/x86, ppc64/ppc, sparc64/sparc, etc...). |
| 18 | //config: |
| 19 | //config:config LINUX32 |
| 20 | //config: bool "linux32" |
| 21 | //config: default y |
| 22 | //config: select PLATFORM_LINUX |
| 23 | //config: help |
| 24 | //config: Alias to "setarch linux32". |
| 25 | //config: |
| 26 | //config:config LINUX64 |
| 27 | //config: bool "linux64" |
| 28 | //config: default y |
| 29 | //config: select PLATFORM_LINUX |
| 30 | //config: help |
| 31 | //config: Alias to "setarch linux64". |
| 32 | |
| 33 | //applet:IF_SETARCH(APPLET(setarch, BB_DIR_BIN, BB_SUID_DROP)) |
| 34 | //applet:IF_LINUX32(APPLET_ODDNAME(linux32, setarch, BB_DIR_BIN, BB_SUID_DROP, linux32)) |
| 35 | //applet:IF_LINUX64(APPLET_ODDNAME(linux64, setarch, BB_DIR_BIN, BB_SUID_DROP, linux64)) |
| 36 | |
| 37 | //kbuild:lib-$(CONFIG_SETARCH) += setarch.o |
| 38 | //kbuild:lib-$(CONFIG_LINUX32) += setarch.o |
| 39 | //kbuild:lib-$(CONFIG_LINUX64) += setarch.o |
| 40 | |
| 41 | //usage:#define setarch_trivial_usage |
| 42 | //usage: "PERSONALITY [-R] PROG ARGS" |
| 43 | //usage:#define setarch_full_usage "\n\n" |
| 44 | //usage: "PERSONALITY may be:" |
| 45 | //usage: "\n"" linux32 Set 32bit uname emulation" |
| 46 | //usage: "\n"" linux64 Set 64bit uname emulation" |
| 47 | //usage: "\n" |
| 48 | //usage: "\n"" -R Disable address space randomization" |
| 49 | //usage: |
| 50 | //usage:#define linux32_trivial_usage NOUSAGE_STR |
| 51 | //usage:#define linux32_full_usage "" |
| 52 | //usage: |
| 53 | //usage:#define linux64_trivial_usage NOUSAGE_STR |
| 54 | //usage:#define linux64_full_usage "" |
| 55 | |
| 56 | #include "libbb.h" |
| 57 | #include <sys/personality.h> |
| 58 | |
| 59 | #ifndef ADDR_NO_RANDOMIZE |
| 60 | # define ADDR_NO_RANDOMIZE 0x0040000 |
| 61 | #endif |
| 62 | |
| 63 | int setarch_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
| 64 | int setarch_main(int argc UNUSED_PARAM, char **argv) |
| 65 | { |
| 66 | unsigned opts; |
| 67 | unsigned long pers; |
| 68 | |
| 69 | /* Figure out what personality we are supposed to switch to ... |
| 70 | * we can be invoked as either: |
| 71 | * argv[0],argv[1] == "setarch","personality" |
| 72 | * argv[0] == "personality" |
| 73 | */ |
| 74 | if (ENABLE_SETARCH && applet_name[0] == 's' |
| 75 | && argv[1] && is_prefixed_with(argv[1], "linux") |
| 76 | ) { |
| 77 | argv++; |
| 78 | applet_name = argv[0]; |
| 79 | } |
| 80 | if ((!ENABLE_SETARCH && !ENABLE_LINUX32) || applet_name[5] == '6') |
| 81 | /* linux64 */ |
| 82 | pers = PER_LINUX; |
| 83 | else |
| 84 | if ((!ENABLE_SETARCH && !ENABLE_LINUX64) || applet_name[5] == '3') |
| 85 | /* linux32 */ |
| 86 | pers = PER_LINUX32; |
| 87 | else |
| 88 | bb_show_usage(); |
| 89 | |
| 90 | opts = getopt32(argv, "+R"); /* '+': stop at first non-option */ |
| 91 | if (opts) |
| 92 | pers |= ADDR_NO_RANDOMIZE; |
| 93 | |
| 94 | /* Try to set personality */ |
| 95 | if (personality(pers) < 0) |
| 96 | bb_perror_msg_and_die("personality(0x%lx)", pers); |
| 97 | |
| 98 | argv += optind; |
| 99 | if (!argv[0]) |
| 100 | (--argv)[0] = (char*)"/bin/sh"; |
| 101 | |
| 102 | /* Try to execute the program */ |
| 103 | BB_EXECVP_or_die(argv); |
| 104 | } |
| 105 |