blob: 6025d43fe2b3b97fb6d0b3cc071aae14cb37c429 [file] [log] [blame]
/* Toybox infrastructure.
*
* Copyright 2006 Rob Landley <rob@landley.net>
*/
#include "toys.h"
#ifndef TOYBOX_VERSION
#define TOYBOX_VERSION "0.7.4"
#endif
// Populate toy_list[].
#undef NEWTOY
#undef OLDTOY
#define NEWTOY(name, opts, flags) {#name, name##_main, OPTSTR_##name, flags},
#define OLDTOY(name, oldname, flags) \
{#name, oldname##_main, OPTSTR_##oldname, flags},
struct toy_list toy_list[] = {
#include "generated/newtoys.h"
};
// global context for this command.
struct toy_context toys;
union global_union this;
char toybuf[4096], libbuf[4096];
struct toy_list *toy_find(char *name)
{
int top, bottom, middle;
if (!CFG_TOYBOX) return 0;
// If the name starts with "toybox" accept that as a match. Otherwise
// skip the first entry, which is out of order.
if (!strncmp(name,"toybox",6)) return toy_list;
bottom = 1;
// Binary search to find this command.
top = ARRAY_LEN(toy_list)-1;
for (;;) {
int result;
middle = (top+bottom)/2;
if (middle<bottom || middle>top) return NULL;
result = strcmp(name,toy_list[middle].name);
if (!result) return toy_list+middle;
if (result<0) top = --middle;
else bottom = ++middle;
}
}
// Figure out whether or not anything is using the option parsing logic,
// because the compiler can't figure out whether or not to optimize it away
// on its' own. NEED_OPTIONS becomes a constant allowing if() to optimize
// stuff out via dead code elimination.
#undef NEWTOY
#undef OLDTOY
#define NEWTOY(name, opts, flags) opts ||
#define OLDTOY(name, oldname, flags) OPTSTR_##oldname ||
static const int NEED_OPTIONS =
#include "generated/newtoys.h"
0; // Ends the opts || opts || opts...
static void unknown(char *name)
{
toys.exitval = 127;
toys.which = toy_list;
error_exit("Unknown command %s", name);
}
// Setup toybox global state for this command.
static void toy_singleinit(struct toy_list *which, char *argv[])
{
toys.which = which;
toys.argv = argv;
if (CFG_TOYBOX_I18N) setlocale(LC_ALL, "C"+!!(which->flags & TOYFLAG_LOCALE));
// Parse --help and --version for (almost) all commands
if (CFG_TOYBOX_HELP_DASHDASH && !(which->flags & TOYFLAG_NOHELP) && argv[1]) {
if (!strcmp(argv[1], "--help")) {
if (CFG_TOYBOX && toys.which == toy_list && toys.argv[2])
if (!(toys.which = toy_find(toys.argv[2]))) unknown(toys.argv[2]);
show_help(stdout);
xexit();
}
if (!strcmp(argv[1], "--version")) {
xputs("toybox "TOYBOX_VERSION);
xexit();
}
}
if (NEED_OPTIONS && which->options) get_optflags();
else {
toys.optargs = argv+1;
for (toys.optc = 0; toys.optargs[toys.optc]; toys.optc++);
}
toys.old_umask = umask(0);
if (!(which->flags & TOYFLAG_UMASK)) umask(toys.old_umask);
toys.signalfd--;
toys.toycount = ARRAY_LEN(toy_list);
}
// Full init needed by multiplexer or reentrant calls, calls singleinit at end
void toy_init(struct toy_list *which, char *argv[])
{
void *oldwhich = toys.which;
// Drop permissions for non-suid commands.
if (CFG_TOYBOX_SUID) {
if (!toys.which) toys.which = toy_list;
uid_t uid = getuid(), euid = geteuid();
if (!(which->flags & TOYFLAG_STAYROOT)) {
if (uid != euid) {
if (setuid(uid)) perror_exit("setuid %d->%d", euid, uid); // drop root
euid = uid;
toys.wasroot++;
}
} else if (CFG_TOYBOX_DEBUG && uid && which != toy_list)
error_msg("Not installed suid root");
if ((which->flags & TOYFLAG_NEEDROOT) && euid) help_exit("Not root");
}
// Free old toys contents (to be reentrant), but leave rebound if any
// don't blank old optargs if our new argc lives in the old optargs.
if (argv<toys.optargs || argv>toys.optargs+toys.optc) free(toys.optargs);
memset(&toys, 0, offsetof(struct toy_context, rebound));
if (oldwhich) memset(&this, 0, sizeof(this));
// Continue to portion of init needed by standalone commands
toy_singleinit(which, argv);
}
// Like exec() but runs an internal toybox command instead of another file.
// Only returns if it can't run command internally, otherwise exit() when done.
void toy_exec(char *argv[])
{
struct toy_list *which;
// Return if we can't find it (which includes no multiplexer case),
if (!(which = toy_find(*argv))) return;
// Return if stack depth getting noticeable (proxy for leaked heap, etc).
// Compiler writers have decided subtracting char * is undefined behavior,
// so convert to integers. (LP64 says sizeof(long)==sizeof(pointer).)
if (!CFG_TOYBOX_NORECURSE)
if (toys.stacktop && labs((long)toys.stacktop-(long)&which)>6000) return;
// Return if we need to re-exec to acquire root via suid bit.
if (toys.which && (which->flags&TOYFLAG_ROOTONLY) && toys.wasroot) return;
// Run command
toy_init(which, argv);
if (toys.which) toys.which->toy_main();
xexit();
}
// Multiplexer command, first argument is command to run, rest are args to that.
// If first argument starts with - output list of command install paths.
void toybox_main(void)
{
static char *toy_paths[]={"usr/","bin/","sbin/",0};
int i, len = 0;
// fast path: try to exec immediately.
// (Leave toys.which null to disable suid return logic.)
if (toys.argv[1]) toy_exec(toys.argv+1);
// For early error reporting
toys.which = toy_list;
if (toys.argv[1] && toys.argv[1][0] != '-') unknown(toys.argv[1]);
// Output list of command.
for (i=1; i<ARRAY_LEN(toy_list); i++) {
int fl = toy_list[i].flags;
if (fl & TOYMASK_LOCATION) {
if (toys.argv[1]) {
int j;
for (j=0; toy_paths[j]; j++)
if (fl & (1<<j)) len += printf("%s", toy_paths[j]);
}
len += printf("%s",toy_list[i].name);
if (++len > 65) len = 0;
xputc(len ? ' ' : '\n');
}
}
xputc('\n');
}
int main(int argc, char *argv[])
{
if (!*argv) return 127;
// Snapshot stack location so we can detect recursion depth later.
// This is its own block so probe doesn't permanently consume stack.
else {
int stack;
toys.stacktop = &stack;
}
*argv = getbasename(*argv);
// Up to and including Android M, bionic's dynamic linker added a handler to
// cause a crash dump on SIGPIPE. That was removed in Android N, but adbd
// was still setting the SIGPIPE disposition to SIG_IGN, and its children
// were inheriting that. In Android O, adbd is fixed, but manually asking
// for the default disposition is harmless, and it'll be a long time before
// no one's using anything older than O!
if (CFG_TOYBOX_ON_ANDROID) signal(SIGPIPE, SIG_DFL);
// If nommu can't fork, special reentry path.
// Use !stacktop to signal "vfork happened", both before and after xexec()
if (!CFG_TOYBOX_FORK) {
if (0x80 & **argv) {
**argv &= 0x7f;
toys.stacktop = 0;
}
}
if (CFG_TOYBOX) {
// Call the multiplexer, adjusting this argv[] to be its' argv[1].
// (It will adjust it back before calling toy_exec().)
toys.argv = argv-1;
toybox_main();
} else {
// a single toybox command built standalone with no multiplexer
toy_singleinit(toy_list, argv);
toy_list->toy_main();
}
xexit();
}