From 63cb2f345484a34bac9086e8e389d4bf5d96b77f Mon Sep 17 00:00:00 2001
From: Jeremy Soller <jeremy@system76.com>
Date: Sat, 13 Apr 2019 21:14:52 -0600
Subject: [PATCH] ld.so: Add auxv support, get ld_library_path from env
---
src/ld_so/start.rs | 72 ++++++++++++++++++++++++++++++++++++++++++----
1 file changed, 67 insertions(+), 5 deletions(-)
diff --git a/src/ld_so/start.rs b/src/ld_so/start.rs
index 88437c43..73110e7b 100644
--- a/src/ld_so/start.rs
+++ b/src/ld_so/start.rs
@@ -20,19 +20,77 @@ pub extern "C" fn relibc_ld_so_start(sp: &'static mut Stack) -> usize {
loop {}
}
+ // Some variables that will be overridden by environment and auxiliary vectors
+ let mut library_path = "/lib";
+ let mut page_size = 4096;
+
// Pop the first argument (path to ld_so), and get the path of the program
- // TODO: Also retrieve LD_LIBRARY_PATH this way
let path_c = unsafe {
- let mut argv = &mut sp.argv0 as *mut *const c_char;
+ let mut argv = &mut sp.argv0 as *mut *const c_char as *mut usize;
+
+ // Move arguments
loop {
let next_argv = argv.add(1);
let arg = *next_argv;
*argv = arg;
argv = next_argv;
- if arg.is_null() {
+ if arg == 0 {
+ break;
+ }
+
+ if let Ok(arg_str) = CStr::from_ptr(arg as *const c_char).to_str() {
+ println!(" arg: '{}'", arg_str);
+ }
+ }
+
+ // Move environment
+ loop {
+ let next_argv = argv.add(1);
+ let arg = *next_argv;
+ *argv = arg;
+ argv = next_argv;
+ if arg == 0 {
+ break;
+ }
+
+ if let Ok(arg_str) = CStr::from_ptr(arg as *const c_char).to_str() {
+ println!(" env: '{}'", arg_str);
+
+ let mut parts = arg_str.splitn(2, '=');
+ if let Some(key) = parts.next() {
+ if let Some(value) = parts.next() {
+ match key {
+ "LD_LIBRARY_PATH" => library_path = value,
+ _ => ()
+ }
+ }
+ }
+ }
+ }
+
+ // Move auxiliary vectors
+ loop {
+ let next_argv = argv.add(1);
+ let kind = *next_argv;
+ *argv = kind;
+ argv = next_argv;
+
+ let next_argv = argv.add(1);
+ let value = *next_argv;
+ *argv = value;
+ argv = next_argv;
+
+ if kind == 0 {
break;
}
+
+ println!(" aux: {}={:#x}", kind, value);
+ match kind {
+ 6 => page_size = value,
+ _ => (),
+ }
}
+
sp.argc -= 1;
CStr::from_ptr(sp.argv0)
@@ -47,7 +105,7 @@ pub extern "C" fn relibc_ld_so_start(sp: &'static mut Stack) -> usize {
}
};
- let mut linker = Linker::new("/usr/local/lib:/lib/x86_64-linux-gnu");
+ let mut linker = Linker::new(library_path);
match linker.load(&path, &path) {
Ok(()) => (),
Err(err) => {
@@ -58,7 +116,11 @@ pub extern "C" fn relibc_ld_so_start(sp: &'static mut Stack) -> usize {
}
match linker.link(&path) {
- Ok(entry) => entry,
+ Ok(entry) => {
+ eprintln!("ld.so: entry '{}': {:#x}", path, entry);
+ //unistd::_exit(0);
+ entry
+ },
Err(err) => {
eprintln!("ld.so: failed to link '{}': {}", path, err);
unistd::_exit(1);
--
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