1 /* Toybox infrastructure.
2 *
3 * Copyright 2006 Rob Landley <rob@landley.net>
4 */
5
6 #include "toys.h"
7
8 #ifndef TOYBOX_VERSION
9 #define TOYBOX_VERSION "0.5.2"
10 #endif
11
12 // Populate toy_list[].
13
14 #undef NEWTOY
15 #undef OLDTOY
16 #define NEWTOY(name, opts, flags) {#name, name##_main, opts, flags},
17 #define OLDTOY(name, oldname, flags) \
18 {#name, oldname##_main, OPTSTR_##oldname, flags},
19
20 struct toy_list toy_list[] = {
21 #include "generated/newtoys.h"
22 };
23
24 // global context for this command.
25
26 struct toy_context toys;
27 union global_union this;
28 char toybuf[4096], libbuf[4096];
29
toy_find(char * name)30 struct toy_list *toy_find(char *name)
31 {
32 int top, bottom, middle;
33
34 if (!CFG_TOYBOX) return 0;
35
36 // If the name starts with "toybox" accept that as a match. Otherwise
37 // skip the first entry, which is out of order.
38
39 if (!strncmp(name,"toybox",6)) return toy_list;
40 bottom = 1;
41
42 // Binary search to find this command.
43
44 top = ARRAY_LEN(toy_list)-1;
45 for (;;) {
46 int result;
47
48 middle = (top+bottom)/2;
49 if (middle<bottom || middle>top) return NULL;
50 result = strcmp(name,toy_list[middle].name);
51 if (!result) return toy_list+middle;
52 if (result<0) top=--middle;
53 else bottom = ++middle;
54 }
55 }
56
57 // Figure out whether or not anything is using the option parsing logic,
58 // because the compiler can't figure out whether or not to optimize it away
59 // on its' own. NEED_OPTIONS becomes a constant allowing if() to optimize
60 // stuff out via dead code elimination.
61
62 #undef NEWTOY
63 #undef OLDTOY
64 #define NEWTOY(name, opts, flags) opts ||
65 #define OLDTOY(name, oldname, flags) OPTSTR_##oldname ||
66 static const int NEED_OPTIONS =
67 #include "generated/newtoys.h"
68 0; // Ends the opts || opts || opts...
69
70 // Subset of init needed by singlemain
toy_singleinit(struct toy_list * which,char * argv[])71 static void toy_singleinit(struct toy_list *which, char *argv[])
72 {
73 toys.which = which;
74 toys.argv = argv;
75
76 if (CFG_TOYBOX_I18N) setlocale(LC_ALL, "C"+!!(which->flags & TOYFLAG_LOCALE));
77
78 if (CFG_TOYBOX_HELP_DASHDASH && argv[1] && !strcmp(argv[1], "--help")) {
79 if (CFG_TOYBOX && toys.which == toy_list && toys.argv[2])
80 if (!(toys.which = toy_find(toys.argv[2]))) return;
81 show_help();
82 xexit();
83 }
84
85 if (NEED_OPTIONS && which->options) get_optflags();
86 else {
87 toys.optargs = argv+1;
88 for (toys.optc=0; toys.optargs[toys.optc]; toys.optc++);
89 }
90 toys.old_umask = umask(0);
91 if (!(which->flags & TOYFLAG_UMASK)) umask(toys.old_umask);
92 toys.signalfd--;
93 toys.toycount = ARRAY_LEN(toy_list);
94 }
95
96 // Setup toybox global state for this command.
97
toy_init(struct toy_list * which,char * argv[])98 void toy_init(struct toy_list *which, char *argv[])
99 {
100 // Drop permissions for non-suid commands.
101
102 if (CFG_TOYBOX_SUID) {
103 uid_t uid = getuid(), euid = geteuid();
104
105 if (!(which->flags & TOYFLAG_STAYROOT)) {
106 if (uid != euid) {
107 if (!setuid(uid)) perror_exit("setuid %d->%d", euid, uid); // drop root
108 else euid = uid;
109 }
110 } else if (CFG_TOYBOX_DEBUG && uid && which != toy_list)
111 error_msg("Not installed suid root");
112
113 if ((which->flags & TOYFLAG_NEEDROOT) && euid) {
114 toys.exithelp++;
115 error_exit("Not root");
116 }
117 }
118
119 // Free old toys contents (to be reentrant), but leave rebound if any
120
121 if (toys.optargs != toys.argv+1) free(toys.optargs);
122 memset(&toys, 0, offsetof(struct toy_context, rebound));
123 if (toys.recursion > 1) memset(&this, 0, sizeof(this));
124
125 // Subset of init needed by singlemain.
126 toy_singleinit(which, argv);
127 }
128
129 // Like exec() but runs an internal toybox command instead of another file.
130 // Only returns if it can't run command internally, otherwise exit() when done.
toy_exec(char * argv[])131 void toy_exec(char *argv[])
132 {
133 struct toy_list *which;
134
135 // Return if we can't find it, or need to re-exec to acquire root,
136 // or if stack depth is getting silly.
137 if (!(which = toy_find(argv[0]))) return;
138 if (toys.recursion && (which->flags & TOYFLAG_ROOTONLY) && getuid()) return;
139 if (toys.recursion++ > 5) return;
140
141 // don't blank old optargs if our new argc lives in the old optargs.
142 if (argv>=toys.optargs && argv<=toys.optargs+toys.optc) toys.optargs = 0;
143
144 // Run command
145 toy_init(which, argv);
146 if (toys.which) toys.which->toy_main();
147 xexit();
148 }
149
150 // Multiplexer command, first argument is command to run, rest are args to that.
151 // If first argument starts with - output list of command install paths.
152
toybox_main(void)153 void toybox_main(void)
154 {
155 static char *toy_paths[]={"usr/","bin/","sbin/",0};
156 int i, len = 0;
157
158 toys.which = toy_list;
159 if (toys.argv[1]) {
160 toys.optc = toys.recursion = 0;
161 toy_exec(toys.argv+1);
162 if (!strcmp("--version", toys.argv[1])) {
163 xputs(TOYBOX_VERSION);
164 xexit();
165 }
166 if (toys.argv[1][0] != '-') error_exit("Unknown command %s", toys.argv[1]);
167 }
168
169 // Output list of command.
170 for (i=1; i<ARRAY_LEN(toy_list); i++) {
171 int fl = toy_list[i].flags;
172 if (fl & TOYMASK_LOCATION) {
173 if (toys.argv[1]) {
174 int j;
175 for (j=0; toy_paths[j]; j++)
176 if (fl & (1<<j)) len += printf("%s", toy_paths[j]);
177 }
178 len += printf("%s",toy_list[i].name);
179 if (++len > 65) len = 0;
180 xputc(len ? ' ' : '\n');
181 }
182 }
183 xputc('\n');
184 }
185
main(int argc,char * argv[])186 int main(int argc, char *argv[])
187 {
188 // We check our own stdout errors, disable sigpipe killer
189 signal(SIGPIPE, SIG_IGN);
190
191 if (CFG_TOYBOX) {
192 // Trim path off of command name
193 *argv = basename(*argv);
194
195 // Call the multiplexer, adjusting this argv[] to be its' argv[1].
196 // (It will adjust it back before calling toy_exec().)
197 toys.argv = argv-1;
198 toybox_main();
199 } else {
200 // a single toybox command built standalone with no multiplexer
201 toy_singleinit(toy_list, argv);
202 toy_list->toy_main();
203 }
204
205 xexit();
206 }
207