aboutsummaryrefslogtreecommitdiff
path: root/main.c
diff options
context:
space:
mode:
Diffstat (limited to 'main.c')
-rw-r--r--main.c63
1 files changed, 40 insertions, 23 deletions
diff --git a/main.c b/main.c
index dcd486eb..1e562b06 100644
--- a/main.c
+++ b/main.c
@@ -67,7 +67,7 @@ static const int NEED_OPTIONS =
#include "generated/newtoys.h"
0; // Ends the opts || opts || opts...
-// Subset of init needed by singlemain
+// Setup toybox global state for this command.
static void toy_singleinit(struct toy_list *which, char *argv[])
{
toys.which = which;
@@ -85,7 +85,7 @@ static void toy_singleinit(struct toy_list *which, char *argv[])
if (NEED_OPTIONS && which->options) get_optflags();
else {
toys.optargs = argv+1;
- for (toys.optc=0; toys.optargs[toys.optc]; toys.optc++);
+ for (toys.optc = 0; toys.optargs[toys.optc]; toys.optc++);
}
toys.old_umask = umask(0);
if (!(which->flags & TOYFLAG_UMASK)) umask(toys.old_umask);
@@ -93,8 +93,7 @@ static void toy_singleinit(struct toy_list *which, char *argv[])
toys.toycount = ARRAY_LEN(toy_list);
}
-// Setup toybox global state for this command.
-
+// Full init needed by multiplexer or reentrant calls, calls singleinit at end
void toy_init(struct toy_list *which, char *argv[])
{
// Drop permissions for non-suid commands.
@@ -114,12 +113,12 @@ void toy_init(struct toy_list *which, char *argv[])
}
// Free old toys contents (to be reentrant), but leave rebound if any
-
- if (toys.optargs != toys.argv+1) free(toys.optargs);
+ // 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 (toys.recursion > 1) memset(&this, 0, sizeof(this));
+ if (toys.which) memset(&this, 0, sizeof(this));
- // Subset of init needed by singlemain.
+ // Continue to portion of init needed by standalone commands
toy_singleinit(which, argv);
}
@@ -129,14 +128,15 @@ void toy_exec(char *argv[])
{
struct toy_list *which;
- // Return if we can't find it, or need to re-exec to acquire root,
- // or if stack depth is getting silly.
- if (!(which = toy_find(argv[0]))) return;
- if (toys.recursion && (which->flags & TOYFLAG_ROOTONLY) && getuid()) return;
- if (toys.recursion++ > 5) return;
+ // Return if we can't find it (which includes no multiplexer case),
+ if (!(which = toy_find(*argv))) return;
- // don't blank old optargs if our new argc lives in the old optargs.
- if (argv>=toys.optargs && argv<=toys.optargs+toys.optc) toys.optargs = 0;
+ // Return if stack depth getting noticeable (proxy for leaked heap, etc).
+ if (toys.stacktop && labs((char *)toys.stacktop-(char *)&which)>6000)
+ return;
+
+ // Return if we need to re-exec to acquire root via suid bit.
+ if (toys.which && (which->flags&TOYFLAG_ROOTONLY) && getuid()) return;
// Run command
toy_init(which, argv);
@@ -146,16 +146,19 @@ void toy_exec(char *argv[])
// 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.optc = toys.recursion = 0;
- toy_exec(toys.argv+1);
if (!strcmp("--version", toys.argv[1])) {
xputs(TOYBOX_VERSION);
xexit();
@@ -185,13 +188,27 @@ void toybox_main(void)
int main(int argc, char *argv[])
{
- // We check our own stdout errors, disable sigpipe killer
- signal(SIGPIPE, SIG_IGN);
+ if (!*argv) return 127;
- if (CFG_TOYBOX) {
- // Trim path off of command name
- *argv = basename(*argv);
+ // 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 = basename_r(*argv);
+
+ // 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;