1 | /* vi: set sw=4 ts=4: */
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2 | /*
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3 | * Utility routines.
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4 | *
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5 | * Copyright (C) tons of folks. Tracking down who wrote what
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6 | * isn't something I'm going to worry about... If you wrote something
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7 | * here, please feel free to acknowledge your work.
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8 | *
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9 | * Based in part on code from sash, Copyright (c) 1999 by David I. Bell
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10 | * Permission has been granted to redistribute this code under GPL.
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11 | *
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12 | * Licensed under GPLv2 or later, see file LICENSE in this source tree.
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13 | */
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14 |
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15 | /* We are trying to not use printf, this benefits the case when selected
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16 | * applets are really simple. Example:
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17 | *
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18 | * $ ./busybox
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19 | * ...
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20 | * Currently defined functions:
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21 | * basename, false, true
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22 | *
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23 | * $ size busybox
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24 | * text data bss dec hex filename
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25 | * 4473 52 72 4597 11f5 busybox
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26 | *
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27 | * FEATURE_INSTALLER or FEATURE_SUID will still link printf routines in. :(
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28 | */
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29 | #include "busybox.h"
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30 |
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31 | #if !(defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__NetBSD__) \
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32 | || defined(__APPLE__) \
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33 | )
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34 | # include <malloc.h> /* for mallopt */
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35 | #endif
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36 |
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37 |
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38 | /* Declare <applet>_main() */
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39 | #define PROTOTYPES
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40 | #include "applets.h"
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41 | #undef PROTOTYPES
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42 |
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43 | /* Include generated applet names, pointers to <applet>_main, etc */
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44 | #include "applet_tables.h"
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45 | /* ...and if applet_tables generator says we have only one applet... */
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46 | #ifdef SINGLE_APPLET_MAIN
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47 | # undef ENABLE_FEATURE_INDIVIDUAL
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48 | # define ENABLE_FEATURE_INDIVIDUAL 1
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49 | # undef IF_FEATURE_INDIVIDUAL
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50 | # define IF_FEATURE_INDIVIDUAL(...) __VA_ARGS__
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51 | #endif
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52 |
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53 | #include "usage_compressed.h"
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54 |
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55 |
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56 | #if ENABLE_SHOW_USAGE && !ENABLE_FEATURE_COMPRESS_USAGE
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57 | static const char usage_messages[] ALIGN1 = UNPACKED_USAGE;
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58 | #else
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59 | # define usage_messages 0
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60 | #endif
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61 |
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62 | #if ENABLE_FEATURE_COMPRESS_USAGE
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63 |
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64 | static const char packed_usage[] ALIGN1 = { PACKED_USAGE };
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65 | # include "bb_archive.h"
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66 | static const char *unpack_usage_messages(void)
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67 | {
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68 | char *outbuf = NULL;
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69 | bunzip_data *bd;
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70 | int i;
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71 |
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72 | i = start_bunzip(&bd,
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73 | /* src_fd: */ -1,
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74 | /* inbuf: */ packed_usage,
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75 | /* len: */ sizeof(packed_usage));
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76 | /* read_bunzip can longjmp to start_bunzip, and ultimately
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77 | * end up here with i != 0 on read data errors! Not trivial */
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78 | if (!i) {
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79 | /* Cannot use xmalloc: will leak bd in NOFORK case! */
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80 | outbuf = malloc_or_warn(sizeof(UNPACKED_USAGE));
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81 | if (outbuf)
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82 | read_bunzip(bd, outbuf, sizeof(UNPACKED_USAGE));
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83 | }
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84 | dealloc_bunzip(bd);
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85 | return outbuf;
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86 | }
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87 | # define dealloc_usage_messages(s) free(s)
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88 |
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89 | #else
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90 |
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91 | # define unpack_usage_messages() usage_messages
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92 | # define dealloc_usage_messages(s) ((void)(s))
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93 |
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94 | #endif /* FEATURE_COMPRESS_USAGE */
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95 |
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96 |
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97 | void FAST_FUNC bb_show_usage(void)
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98 | {
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99 | if (ENABLE_SHOW_USAGE) {
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100 | #ifdef SINGLE_APPLET_STR
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101 | /* Imagine that this applet is "true". Dont suck in printf! */
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102 | const char *usage_string = unpack_usage_messages();
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103 |
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104 | if (*usage_string == '\b') {
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105 | full_write2_str("No help available.\n\n");
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106 | } else {
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107 | full_write2_str("Usage: "SINGLE_APPLET_STR" ");
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108 | full_write2_str(usage_string);
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109 | full_write2_str("\n\n");
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110 | }
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111 | if (ENABLE_FEATURE_CLEAN_UP)
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112 | dealloc_usage_messages((char*)usage_string);
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113 | #else
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114 | const char *p;
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115 | const char *usage_string = p = unpack_usage_messages();
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116 | int ap = find_applet_by_name(applet_name);
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117 |
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118 | if (ap < 0) /* never happens, paranoia */
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119 | xfunc_die();
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120 | while (ap) {
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121 | while (*p++) continue;
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122 | ap--;
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123 | }
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124 | full_write2_str(bb_banner);
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125 | full_write2_str(" multi-call binary.\n");
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126 | if (*p == '\b')
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127 | full_write2_str("\nNo help available.\n\n");
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128 | else {
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129 | full_write2_str("\nUsage: ");
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130 | full_write2_str(applet_name);
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131 | full_write2_str(" ");
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132 | full_write2_str(p);
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133 | full_write2_str("\n\n");
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134 | }
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135 | if (ENABLE_FEATURE_CLEAN_UP)
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136 | dealloc_usage_messages((char*)usage_string);
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137 | #endif
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138 | }
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139 | xfunc_die();
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140 | }
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141 |
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142 | #if NUM_APPLETS > 8
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143 | static int applet_name_compare(const void *name, const void *idx)
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144 | {
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145 | int i = (int)(ptrdiff_t)idx - 1;
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146 | return strcmp(name, APPLET_NAME(i));
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147 | }
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148 | #endif
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149 | int FAST_FUNC find_applet_by_name(const char *name)
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150 | {
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151 | #if NUM_APPLETS > 8
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152 | /* Do a binary search to find the applet entry given the name. */
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153 | const char *p;
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154 | p = bsearch(name, (void*)(ptrdiff_t)1, ARRAY_SIZE(applet_main), 1, applet_name_compare);
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155 | /*
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156 | * if (!p) return -1;
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157 | * ^^^^^^^^^^^^^^^^^^ the code below will do this if p == NULL :)
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158 | */
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159 | return (int)(ptrdiff_t)p - 1;
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160 | #else
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161 | /* A version which does not pull in bsearch */
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162 | int i = 0;
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163 | const char *p = applet_names;
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164 | while (i < NUM_APPLETS) {
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165 | if (strcmp(name, p) == 0)
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166 | return i;
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167 | p += strlen(p) + 1;
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168 | i++;
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169 | }
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170 | return -1;
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171 | #endif
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172 | }
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173 |
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174 |
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175 | void lbb_prepare(const char *applet
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176 | IF_FEATURE_INDIVIDUAL(, char **argv))
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177 | MAIN_EXTERNALLY_VISIBLE;
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178 | void lbb_prepare(const char *applet
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179 | IF_FEATURE_INDIVIDUAL(, char **argv))
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180 | {
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181 | #ifdef __GLIBC__
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182 | (*(int **)&bb_errno) = __errno_location();
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183 | barrier();
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184 | #endif
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185 | applet_name = applet;
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186 |
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187 | /* Set locale for everybody except 'init' */
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188 | if (ENABLE_LOCALE_SUPPORT && getpid() != 1)
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189 | setlocale(LC_ALL, "");
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190 |
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191 | #if ENABLE_FEATURE_INDIVIDUAL
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192 | /* Redundant for busybox (run_applet_and_exit covers that case)
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193 | * but needed for "individual applet" mode */
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194 | if (argv[1]
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195 | && !argv[2]
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196 | && strcmp(argv[1], "--help") == 0
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197 | && strncmp(applet, "busybox", 7) != 0
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198 | ) {
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199 | /* Special case. POSIX says "test --help"
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200 | * should be no different from e.g. "test --foo". */
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201 | if (!ENABLE_TEST || strcmp(applet_name, "test") != 0)
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202 | bb_show_usage();
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203 | }
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204 | #endif
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205 | }
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206 |
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207 | /* The code below can well be in applets/applets.c, as it is used only
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208 | * for busybox binary, not "individual" binaries.
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209 | * However, keeping it here and linking it into libbusybox.so
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210 | * (together with remaining tiny applets/applets.o)
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211 | * makes it possible to avoid --whole-archive at link time.
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212 | * This makes (shared busybox) + libbusybox smaller.
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213 | * (--gc-sections would be even better....)
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214 | */
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215 |
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216 | const char *applet_name;
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217 | #if !BB_MMU
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218 | bool re_execed;
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219 | #endif
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220 |
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221 |
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222 | /* If not built as a single-applet executable... */
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223 | #if !defined(SINGLE_APPLET_MAIN)
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224 |
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225 | IF_FEATURE_SUID(static uid_t ruid;) /* real uid */
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226 |
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227 | # if ENABLE_FEATURE_SUID_CONFIG
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228 |
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229 | static struct suid_config_t {
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230 | /* next ptr must be first: this struct needs to be llist-compatible */
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231 | struct suid_config_t *m_next;
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232 | struct bb_uidgid_t m_ugid;
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233 | int m_applet;
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234 | mode_t m_mode;
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235 | } *suid_config;
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236 |
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237 | static bool suid_cfg_readable;
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238 |
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239 | /* check if u is member of group g */
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240 | static int ingroup(uid_t u, gid_t g)
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241 | {
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242 | struct group *grp = getgrgid(g);
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243 | if (grp) {
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244 | char **mem;
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245 | for (mem = grp->gr_mem; *mem; mem++) {
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246 | struct passwd *pwd = getpwnam(*mem);
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247 | if (pwd && (pwd->pw_uid == u))
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248 | return 1;
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249 | }
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250 | }
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251 | return 0;
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252 | }
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253 |
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254 | /* libbb candidate */
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255 | static char *get_trimmed_slice(char *s, char *e)
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256 | {
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257 | /* First, consider the value at e to be nul and back up until we
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258 | * reach a non-space char. Set the char after that (possibly at
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259 | * the original e) to nul. */
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260 | while (e-- > s) {
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261 | if (!isspace(*e)) {
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262 | break;
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263 | }
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264 | }
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265 | e[1] = '\0';
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266 |
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267 | /* Next, advance past all leading space and return a ptr to the
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268 | * first non-space char; possibly the terminating nul. */
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269 | return skip_whitespace(s);
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270 | }
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271 |
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272 | static void parse_config_file(void)
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273 | {
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274 | /* Don't depend on the tools to combine strings. */
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275 | static const char config_file[] ALIGN1 = "/etc/busybox.conf";
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276 |
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277 | struct suid_config_t *sct_head;
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278 | int applet_no;
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279 | FILE *f;
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280 | const char *errmsg;
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281 | unsigned lc;
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282 | smallint section;
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283 | struct stat st;
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284 |
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285 | ruid = getuid();
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286 | if (ruid == 0) /* run by root - don't need to even read config file */
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287 | return;
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288 |
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289 | if ((stat(config_file, &st) != 0) /* No config file? */
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290 | || !S_ISREG(st.st_mode) /* Not a regular file? */
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291 | || (st.st_uid != 0) /* Not owned by root? */
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292 | || (st.st_mode & (S_IWGRP | S_IWOTH)) /* Writable by non-root? */
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293 | || !(f = fopen_for_read(config_file)) /* Cannot open? */
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294 | ) {
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295 | return;
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296 | }
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297 |
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298 | suid_cfg_readable = 1;
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299 | sct_head = NULL;
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300 | section = lc = 0;
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301 |
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302 | while (1) {
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303 | char buffer[256];
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304 | char *s;
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305 |
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306 | if (!fgets(buffer, sizeof(buffer), f)) { /* Are we done? */
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307 | // Looks like bloat
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308 | //if (ferror(f)) { /* Make sure it wasn't a read error. */
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309 | // errmsg = "reading";
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310 | // goto pe_label;
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311 | //}
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312 | fclose(f);
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313 | suid_config = sct_head; /* Success, so set the pointer. */
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314 | return;
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315 | }
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316 |
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317 | s = buffer;
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318 | lc++; /* Got a (partial) line. */
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319 |
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320 | /* If a line is too long for our buffer, we consider it an error.
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321 | * The following test does mistreat one corner case though.
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322 | * If the final line of the file does not end with a newline and
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323 | * yet exactly fills the buffer, it will be treated as too long
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324 | * even though there isn't really a problem. But it isn't really
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325 | * worth adding code to deal with such an unlikely situation, and
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326 | * we do err on the side of caution. Besides, the line would be
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327 | * too long if it did end with a newline. */
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328 | if (!strchr(s, '\n') && !feof(f)) {
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329 | errmsg = "line too long";
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330 | goto pe_label;
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331 | }
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332 |
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333 | /* Trim leading and trailing whitespace, ignoring comments, and
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334 | * check if the resulting string is empty. */
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335 | s = get_trimmed_slice(s, strchrnul(s, '#'));
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336 | if (!*s) {
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337 | continue;
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338 | }
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339 |
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340 | /* Check for a section header. */
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341 |
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342 | if (*s == '[') {
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343 | /* Unlike the old code, we ignore leading and trailing
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344 | * whitespace for the section name. We also require that
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345 | * there are no stray characters after the closing bracket. */
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346 | char *e = strchr(s, ']');
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347 | if (!e /* Missing right bracket? */
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348 | || e[1] /* Trailing characters? */
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349 | || !*(s = get_trimmed_slice(s+1, e)) /* Missing name? */
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350 | ) {
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351 | errmsg = "section header";
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352 | goto pe_label;
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353 | }
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354 | /* Right now we only have one section so just check it.
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355 | * If more sections are added in the future, please don't
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356 | * resort to cascading ifs with multiple strcasecmp calls.
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357 | * That kind of bloated code is all too common. A loop
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358 | * and a string table would be a better choice unless the
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359 | * number of sections is very small. */
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360 | if (strcasecmp(s, "SUID") == 0) {
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361 | section = 1;
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362 | continue;
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363 | }
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364 | section = -1; /* Unknown section so set to skip. */
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365 | continue;
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366 | }
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367 |
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368 | /* Process sections. */
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369 |
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370 | if (section == 1) { /* SUID */
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371 | /* Since we trimmed leading and trailing space above, we're
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372 | * now looking for strings of the form
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373 | * <key>[::space::]*=[::space::]*<value>
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374 | * where both key and value could contain inner whitespace. */
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375 |
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376 | /* First get the key (an applet name in our case). */
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377 | char *e = strchr(s, '=');
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378 | if (e) {
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379 | s = get_trimmed_slice(s, e);
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380 | }
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381 | if (!e || !*s) { /* Missing '=' or empty key. */
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382 | errmsg = "keyword";
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383 | goto pe_label;
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384 | }
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385 |
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386 | /* Ok, we have an applet name. Process the rhs if this
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387 | * applet is currently built in and ignore it otherwise.
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388 | * Note: this can hide config file bugs which only pop
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389 | * up when the busybox configuration is changed. */
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390 | applet_no = find_applet_by_name(s);
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391 | if (applet_no >= 0) {
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392 | unsigned i;
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393 | struct suid_config_t *sct;
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394 |
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395 | /* Note: We currently don't check for duplicates!
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396 | * The last config line for each applet will be the
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397 | * one used since we insert at the head of the list.
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398 | * I suppose this could be considered a feature. */
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399 | sct = xzalloc(sizeof(*sct));
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400 | sct->m_applet = applet_no;
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401 | /*sct->m_mode = 0;*/
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402 | sct->m_next = sct_head;
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403 | sct_head = sct;
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404 |
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405 | /* Get the specified mode. */
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406 |
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407 | e = skip_whitespace(e+1);
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408 |
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409 | for (i = 0; i < 3; i++) {
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410 | /* There are 4 chars for each of user/group/other.
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411 | * "x-xx" instead of "x-" are to make
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412 | * "idx > 3" check catch invalid chars.
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413 | */
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414 | static const char mode_chars[] ALIGN1 = "Ssx-" "Ssx-" "x-xx";
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415 | static const unsigned short mode_mask[] ALIGN2 = {
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416 | S_ISUID, S_ISUID|S_IXUSR, S_IXUSR, 0, /* Ssx- */
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417 | S_ISGID, S_ISGID|S_IXGRP, S_IXGRP, 0, /* Ssx- */
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418 | S_IXOTH, 0 /* x- */
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419 | };
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420 | const char *q = strchrnul(mode_chars + 4*i, *e);
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421 | unsigned idx = q - (mode_chars + 4*i);
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422 | if (idx > 3) {
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423 | errmsg = "mode";
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424 | goto pe_label;
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425 | }
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426 | sct->m_mode |= mode_mask[q - mode_chars];
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427 | e++;
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428 | }
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429 |
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430 | /* Now get the user/group info. */
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431 |
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432 | s = skip_whitespace(e);
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433 | /* Default is 0.0, else parse USER.GROUP: */
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434 | if (*s) {
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435 | /* We require whitespace between mode and USER.GROUP */
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436 | if ((s == e) || !(e = strchr(s, '.'))) {
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437 | errmsg = "uid.gid";
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438 | goto pe_label;
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439 | }
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440 | *e = ':'; /* get_uidgid needs USER:GROUP syntax */
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441 | if (get_uidgid(&sct->m_ugid, s, /*allow_numeric:*/ 1) == 0) {
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442 | errmsg = "unknown user/group";
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443 | goto pe_label;
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444 | }
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445 | }
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446 | }
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447 | continue;
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448 | }
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449 |
|
---|
450 | /* Unknown sections are ignored. */
|
---|
451 |
|
---|
452 | /* Encountering configuration lines prior to seeing a
|
---|
453 | * section header is treated as an error. This is how
|
---|
454 | * the old code worked, but it may not be desirable.
|
---|
455 | * We may want to simply ignore such lines in case they
|
---|
456 | * are used in some future version of busybox. */
|
---|
457 | if (!section) {
|
---|
458 | errmsg = "keyword outside section";
|
---|
459 | goto pe_label;
|
---|
460 | }
|
---|
461 |
|
---|
462 | } /* while (1) */
|
---|
463 |
|
---|
464 | pe_label:
|
---|
465 | fclose(f);
|
---|
466 | bb_error_msg("parse error in %s, line %u: %s", config_file, lc, errmsg);
|
---|
467 |
|
---|
468 | /* Release any allocated memory before returning. */
|
---|
469 | llist_free((llist_t*)sct_head, NULL);
|
---|
470 | }
|
---|
471 | # else
|
---|
472 | static inline void parse_config_file(void)
|
---|
473 | {
|
---|
474 | IF_FEATURE_SUID(ruid = getuid();)
|
---|
475 | }
|
---|
476 | # endif /* FEATURE_SUID_CONFIG */
|
---|
477 |
|
---|
478 |
|
---|
479 | # if ENABLE_FEATURE_SUID
|
---|
480 | static void check_suid(int applet_no)
|
---|
481 | {
|
---|
482 | gid_t rgid; /* real gid */
|
---|
483 |
|
---|
484 | if (ruid == 0) /* set by parse_config_file() */
|
---|
485 | return; /* run by root - no need to check more */
|
---|
486 | rgid = getgid();
|
---|
487 |
|
---|
488 | # if ENABLE_FEATURE_SUID_CONFIG
|
---|
489 | if (suid_cfg_readable) {
|
---|
490 | uid_t uid;
|
---|
491 | struct suid_config_t *sct;
|
---|
492 | mode_t m;
|
---|
493 |
|
---|
494 | for (sct = suid_config; sct; sct = sct->m_next) {
|
---|
495 | if (sct->m_applet == applet_no)
|
---|
496 | goto found;
|
---|
497 | }
|
---|
498 | goto check_need_suid;
|
---|
499 | found:
|
---|
500 | /* Is this user allowed to run this applet? */
|
---|
501 | m = sct->m_mode;
|
---|
502 | if (sct->m_ugid.uid == ruid)
|
---|
503 | /* same uid */
|
---|
504 | m >>= 6;
|
---|
505 | else if ((sct->m_ugid.gid == rgid) || ingroup(ruid, sct->m_ugid.gid))
|
---|
506 | /* same group / in group */
|
---|
507 | m >>= 3;
|
---|
508 | if (!(m & S_IXOTH)) /* is x bit not set? */
|
---|
509 | bb_error_msg_and_die("you have no permission to run this applet");
|
---|
510 |
|
---|
511 | /* We set effective AND saved ids. If saved-id is not set
|
---|
512 | * like we do below, seteuid(0) can still later succeed! */
|
---|
513 |
|
---|
514 | /* Are we directed to change gid
|
---|
515 | * (APPLET = *s* USER.GROUP or APPLET = *S* USER.GROUP)?
|
---|
516 | */
|
---|
517 | if (sct->m_mode & S_ISGID)
|
---|
518 | rgid = sct->m_ugid.gid;
|
---|
519 | /* else: we will set egid = rgid, thus dropping sgid effect */
|
---|
520 | if (setresgid(-1, rgid, rgid))
|
---|
521 | bb_perror_msg_and_die("setresgid");
|
---|
522 |
|
---|
523 | /* Are we directed to change uid
|
---|
524 | * (APPLET = s** USER.GROUP or APPLET = S** USER.GROUP)?
|
---|
525 | */
|
---|
526 | uid = ruid;
|
---|
527 | if (sct->m_mode & S_ISUID)
|
---|
528 | uid = sct->m_ugid.uid;
|
---|
529 | /* else: we will set euid = ruid, thus dropping suid effect */
|
---|
530 | if (setresuid(-1, uid, uid))
|
---|
531 | bb_perror_msg_and_die("setresuid");
|
---|
532 |
|
---|
533 | goto ret;
|
---|
534 | }
|
---|
535 | # if !ENABLE_FEATURE_SUID_CONFIG_QUIET
|
---|
536 | {
|
---|
537 | static bool onetime = 0;
|
---|
538 |
|
---|
539 | if (!onetime) {
|
---|
540 | onetime = 1;
|
---|
541 | bb_error_msg("using fallback suid method");
|
---|
542 | }
|
---|
543 | }
|
---|
544 | # endif
|
---|
545 | check_need_suid:
|
---|
546 | # endif
|
---|
547 | if (APPLET_SUID(applet_no) == BB_SUID_REQUIRE) {
|
---|
548 | /* Real uid is not 0. If euid isn't 0 too, suid bit
|
---|
549 | * is most probably not set on our executable */
|
---|
550 | if (geteuid())
|
---|
551 | bb_error_msg_and_die("must be suid to work properly");
|
---|
552 | } else if (APPLET_SUID(applet_no) == BB_SUID_DROP) {
|
---|
553 | xsetgid(rgid); /* drop all privileges */
|
---|
554 | xsetuid(ruid);
|
---|
555 | }
|
---|
556 | # if ENABLE_FEATURE_SUID_CONFIG
|
---|
557 | ret: ;
|
---|
558 | llist_free((llist_t*)suid_config, NULL);
|
---|
559 | # endif
|
---|
560 | }
|
---|
561 | # else
|
---|
562 | # define check_suid(x) ((void)0)
|
---|
563 | # endif /* FEATURE_SUID */
|
---|
564 |
|
---|
565 |
|
---|
566 | # if ENABLE_FEATURE_INSTALLER
|
---|
567 | static const char usr_bin [] ALIGN1 = "/usr/bin/";
|
---|
568 | static const char usr_sbin[] ALIGN1 = "/usr/sbin/";
|
---|
569 | static const char *const install_dir[] = {
|
---|
570 | &usr_bin [8], /* "/" */
|
---|
571 | &usr_bin [4], /* "/bin/" */
|
---|
572 | &usr_sbin[4] /* "/sbin/" */
|
---|
573 | # if !ENABLE_INSTALL_NO_USR
|
---|
574 | ,usr_bin
|
---|
575 | ,usr_sbin
|
---|
576 | # endif
|
---|
577 | };
|
---|
578 |
|
---|
579 | /* create (sym)links for each applet */
|
---|
580 | static void install_links(const char *busybox, int use_symbolic_links,
|
---|
581 | char *custom_install_dir)
|
---|
582 | {
|
---|
583 | /* directory table
|
---|
584 | * this should be consistent w/ the enum,
|
---|
585 | * busybox.h::bb_install_loc_t, or else... */
|
---|
586 | int (*lf)(const char *, const char *);
|
---|
587 | char *fpc;
|
---|
588 | unsigned i;
|
---|
589 | int rc;
|
---|
590 |
|
---|
591 | lf = link;
|
---|
592 | if (use_symbolic_links)
|
---|
593 | lf = symlink;
|
---|
594 |
|
---|
595 | for (i = 0; i < ARRAY_SIZE(applet_main); i++) {
|
---|
596 | fpc = concat_path_file(
|
---|
597 | custom_install_dir ? custom_install_dir : install_dir[APPLET_INSTALL_LOC(i)],
|
---|
598 | APPLET_NAME(i));
|
---|
599 | // debug: bb_error_msg("%slinking %s to busybox",
|
---|
600 | // use_symbolic_links ? "sym" : "", fpc);
|
---|
601 | rc = lf(busybox, fpc);
|
---|
602 | if (rc != 0 && errno != EEXIST) {
|
---|
603 | bb_simple_perror_msg(fpc);
|
---|
604 | }
|
---|
605 | free(fpc);
|
---|
606 | }
|
---|
607 | }
|
---|
608 | # else
|
---|
609 | # define install_links(x,y,z) ((void)0)
|
---|
610 | # endif
|
---|
611 |
|
---|
612 | /* If we were called as "busybox..." */
|
---|
613 | static int busybox_main(char **argv)
|
---|
614 | {
|
---|
615 | if (!argv[1]) {
|
---|
616 | /* Called without arguments */
|
---|
617 | const char *a;
|
---|
618 | int col;
|
---|
619 | unsigned output_width;
|
---|
620 | help:
|
---|
621 | output_width = 80;
|
---|
622 | if (ENABLE_FEATURE_AUTOWIDTH) {
|
---|
623 | /* Obtain the terminal width */
|
---|
624 | get_terminal_width_height(0, &output_width, NULL);
|
---|
625 | }
|
---|
626 |
|
---|
627 | dup2(1, 2);
|
---|
628 | full_write2_str(bb_banner); /* reuse const string */
|
---|
629 | full_write2_str(" multi-call binary.\n"); /* reuse */
|
---|
630 | full_write2_str(
|
---|
631 | "BusyBox is copyrighted by many authors between 1998-2012.\n"
|
---|
632 | "Licensed under GPLv2. See source distribution for detailed\n"
|
---|
633 | "copyright notices.\n"
|
---|
634 | "\n"
|
---|
635 | "Usage: busybox [function [arguments]...]\n"
|
---|
636 | " or: busybox --list"IF_FEATURE_INSTALLER("[-full]")"\n"
|
---|
637 | IF_FEATURE_INSTALLER(
|
---|
638 | " or: busybox --install [-s] [DIR]\n"
|
---|
639 | )
|
---|
640 | " or: function [arguments]...\n"
|
---|
641 | "\n"
|
---|
642 | "\tBusyBox is a multi-call binary that combines many common Unix\n"
|
---|
643 | "\tutilities into a single executable. Most people will create a\n"
|
---|
644 | "\tlink to busybox for each function they wish to use and BusyBox\n"
|
---|
645 | "\twill act like whatever it was invoked as.\n"
|
---|
646 | "\n"
|
---|
647 | "Currently defined functions:\n"
|
---|
648 | );
|
---|
649 | col = 0;
|
---|
650 | a = applet_names;
|
---|
651 | /* prevent last comma to be in the very last pos */
|
---|
652 | output_width--;
|
---|
653 | while (*a) {
|
---|
654 | int len2 = strlen(a) + 2;
|
---|
655 | if (col >= (int)output_width - len2) {
|
---|
656 | full_write2_str(",\n");
|
---|
657 | col = 0;
|
---|
658 | }
|
---|
659 | if (col == 0) {
|
---|
660 | col = 6;
|
---|
661 | full_write2_str("\t");
|
---|
662 | } else {
|
---|
663 | full_write2_str(", ");
|
---|
664 | }
|
---|
665 | full_write2_str(a);
|
---|
666 | col += len2;
|
---|
667 | a += len2 - 1;
|
---|
668 | }
|
---|
669 | full_write2_str("\n\n");
|
---|
670 | return 0;
|
---|
671 | }
|
---|
672 |
|
---|
673 | if (strncmp(argv[1], "--list", 6) == 0) {
|
---|
674 | unsigned i = 0;
|
---|
675 | const char *a = applet_names;
|
---|
676 | dup2(1, 2);
|
---|
677 | while (*a) {
|
---|
678 | # if ENABLE_FEATURE_INSTALLER
|
---|
679 | if (argv[1][6]) /* --list-full? */
|
---|
680 | full_write2_str(install_dir[APPLET_INSTALL_LOC(i)] + 1);
|
---|
681 | # endif
|
---|
682 | full_write2_str(a);
|
---|
683 | full_write2_str("\n");
|
---|
684 | i++;
|
---|
685 | a += strlen(a) + 1;
|
---|
686 | }
|
---|
687 | return 0;
|
---|
688 | }
|
---|
689 |
|
---|
690 | if (ENABLE_FEATURE_INSTALLER && strcmp(argv[1], "--install") == 0) {
|
---|
691 | int use_symbolic_links;
|
---|
692 | const char *busybox;
|
---|
693 |
|
---|
694 | busybox = xmalloc_readlink(bb_busybox_exec_path);
|
---|
695 | if (!busybox) {
|
---|
696 | /* bb_busybox_exec_path is usually "/proc/self/exe".
|
---|
697 | * In chroot, readlink("/proc/self/exe") usually fails.
|
---|
698 | * In such case, better use argv[0] as symlink target
|
---|
699 | * if it is a full path name.
|
---|
700 | */
|
---|
701 | if (argv[0][0] != '/')
|
---|
702 | bb_error_msg_and_die("'%s' is not an absolute path", argv[0]);
|
---|
703 | busybox = argv[0];
|
---|
704 | }
|
---|
705 | /* busybox --install [-s] [DIR]:
|
---|
706 | * -s: make symlinks
|
---|
707 | * DIR: directory to install links to
|
---|
708 | */
|
---|
709 | use_symbolic_links = (argv[2] && strcmp(argv[2], "-s") == 0 && ++argv);
|
---|
710 | install_links(busybox, use_symbolic_links, argv[2]);
|
---|
711 | return 0;
|
---|
712 | }
|
---|
713 |
|
---|
714 | if (strcmp(argv[1], "--help") == 0) {
|
---|
715 | /* "busybox --help [<applet>]" */
|
---|
716 | if (!argv[2])
|
---|
717 | goto help;
|
---|
718 | /* convert to "<applet> --help" */
|
---|
719 | argv[0] = argv[2];
|
---|
720 | argv[2] = NULL;
|
---|
721 | } else {
|
---|
722 | /* "busybox <applet> arg1 arg2 ..." */
|
---|
723 | argv++;
|
---|
724 | }
|
---|
725 | /* We support "busybox /a/path/to/applet args..." too. Allows for
|
---|
726 | * "#!/bin/busybox"-style wrappers */
|
---|
727 | applet_name = bb_get_last_path_component_nostrip(argv[0]);
|
---|
728 | run_applet_and_exit(applet_name, argv);
|
---|
729 |
|
---|
730 | /*bb_error_msg_and_die("applet not found"); - sucks in printf */
|
---|
731 | full_write2_str(applet_name);
|
---|
732 | full_write2_str(": applet not found\n");
|
---|
733 | xfunc_die();
|
---|
734 | }
|
---|
735 |
|
---|
736 | void FAST_FUNC run_applet_no_and_exit(int applet_no, char **argv)
|
---|
737 | {
|
---|
738 | int argc = 1;
|
---|
739 |
|
---|
740 | while (argv[argc])
|
---|
741 | argc++;
|
---|
742 |
|
---|
743 | /* Reinit some shared global data */
|
---|
744 | xfunc_error_retval = EXIT_FAILURE;
|
---|
745 |
|
---|
746 | applet_name = APPLET_NAME(applet_no);
|
---|
747 | if (argc == 2 && strcmp(argv[1], "--help") == 0) {
|
---|
748 | /* Special case. POSIX says "test --help"
|
---|
749 | * should be no different from e.g. "test --foo". */
|
---|
750 | //TODO: just compare applet_no with APPLET_NO_test
|
---|
751 | if (!ENABLE_TEST || strcmp(applet_name, "test") != 0) {
|
---|
752 | /* If you want "foo --help" to return 0: */
|
---|
753 | /*xfunc_error_retval = 0;*/
|
---|
754 | bb_show_usage();
|
---|
755 | }
|
---|
756 | }
|
---|
757 | if (ENABLE_FEATURE_SUID)
|
---|
758 | check_suid(applet_no);
|
---|
759 | exit(applet_main[applet_no](argc, argv));
|
---|
760 | }
|
---|
761 |
|
---|
762 | void FAST_FUNC run_applet_and_exit(const char *name, char **argv)
|
---|
763 | {
|
---|
764 | int applet = find_applet_by_name(name);
|
---|
765 | if (applet >= 0)
|
---|
766 | run_applet_no_and_exit(applet, argv);
|
---|
767 | if (strncmp(name, "busybox", 7) == 0)
|
---|
768 | exit(busybox_main(argv));
|
---|
769 | }
|
---|
770 |
|
---|
771 | #endif /* !defined(SINGLE_APPLET_MAIN) */
|
---|
772 |
|
---|
773 |
|
---|
774 |
|
---|
775 | #if ENABLE_BUILD_LIBBUSYBOX
|
---|
776 | int lbb_main(char **argv)
|
---|
777 | #else
|
---|
778 | int main(int argc UNUSED_PARAM, char **argv)
|
---|
779 | #endif
|
---|
780 | {
|
---|
781 | /* Tweak malloc for reduced memory consumption */
|
---|
782 | #ifdef M_TRIM_THRESHOLD
|
---|
783 | /* M_TRIM_THRESHOLD is the maximum amount of freed top-most memory
|
---|
784 | * to keep before releasing to the OS
|
---|
785 | * Default is way too big: 256k
|
---|
786 | */
|
---|
787 | mallopt(M_TRIM_THRESHOLD, 8 * 1024);
|
---|
788 | #endif
|
---|
789 | #ifdef M_MMAP_THRESHOLD
|
---|
790 | /* M_MMAP_THRESHOLD is the request size threshold for using mmap()
|
---|
791 | * Default is too big: 256k
|
---|
792 | */
|
---|
793 | mallopt(M_MMAP_THRESHOLD, 32 * 1024 - 256);
|
---|
794 | #endif
|
---|
795 |
|
---|
796 | #if !BB_MMU
|
---|
797 | /* NOMMU re-exec trick sets high-order bit in first byte of name */
|
---|
798 | if (argv[0][0] & 0x80) {
|
---|
799 | re_execed = 1;
|
---|
800 | argv[0][0] &= 0x7f;
|
---|
801 | }
|
---|
802 | #endif
|
---|
803 |
|
---|
804 | #if defined(SINGLE_APPLET_MAIN)
|
---|
805 | /* Only one applet is selected in .config */
|
---|
806 | if (argv[1] && strncmp(argv[0], "busybox", 7) == 0) {
|
---|
807 | /* "busybox <applet> <params>" should still work as expected */
|
---|
808 | argv++;
|
---|
809 | }
|
---|
810 | /* applet_names in this case is just "applet\0\0" */
|
---|
811 | lbb_prepare(applet_names IF_FEATURE_INDIVIDUAL(, argv));
|
---|
812 | return SINGLE_APPLET_MAIN(argc, argv);
|
---|
813 | #else
|
---|
814 | lbb_prepare("busybox" IF_FEATURE_INDIVIDUAL(, argv));
|
---|
815 |
|
---|
816 | applet_name = argv[0];
|
---|
817 | if (applet_name[0] == '-')
|
---|
818 | applet_name++;
|
---|
819 | applet_name = bb_basename(applet_name);
|
---|
820 |
|
---|
821 | parse_config_file(); /* ...maybe, if FEATURE_SUID_CONFIG */
|
---|
822 |
|
---|
823 | run_applet_and_exit(applet_name, argv);
|
---|
824 |
|
---|
825 | /*bb_error_msg_and_die("applet not found"); - sucks in printf */
|
---|
826 | full_write2_str(applet_name);
|
---|
827 | full_write2_str(": applet not found\n");
|
---|
828 | xfunc_die();
|
---|
829 | #endif
|
---|
830 | }
|
---|