SGX target: implement user memory management

Author: Jethro Beekman

src/libstd/lib.rs

@@ -312,7 +312,8 @@
 #![feature(non_exhaustive)]
 #![feature(alloc_layout_extra)]
 #![feature(maybe_uninit)]
-#![cfg_attr(target_env = "sgx", feature(global_asm, range_contains))]
+#![cfg_attr(target_env = "sgx", feature(global_asm, range_contains, slice_index_methods,
+                                        decl_macro, coerce_unsized))]
 
 #![default_lib_allocator]
 

src/libstd/sys/sgx/abi/mem.rs

@@ -11,13 +11,17 @@
 // Do not remove inline: will result in relocation failure
 #[inline(always)]
 pub unsafe fn rel_ptr<T>(offset: u64) -> *const T {
-    (image_base()+offset) as *const T
+    (image_base() + offset) as *const T
 }
 
 // Do not remove inline: will result in relocation failure
 #[inline(always)]
 pub unsafe fn rel_ptr_mut<T>(offset: u64) -> *mut T {
-    (image_base()+offset) as *mut T
+    (image_base() + offset) as *mut T
+}
+
+extern {
+    static ENCLAVE_SIZE: usize;
 }
 
 // Do not remove inline: will result in relocation failure
@@ -26,6 +30,20 @@ pub unsafe fn rel_ptr_mut<T>(offset: u64) -> *mut T {
 #[inline(always)]
 fn image_base() -> u64 {
     let base;
-    unsafe{asm!("lea IMAGE_BASE(%rip),$0":"=r"(base))};
+    unsafe { asm!("lea IMAGE_BASE(%rip),$0":"=r"(base)) };
     base
 }
+
+pub fn is_enclave_range(p: *const u8, len: usize) -> bool {
+    let start=p as u64;
+    let end=start + (len as u64);
+    start >= image_base() &&
+        end <= image_base() + (unsafe { ENCLAVE_SIZE } as u64) // unsafe ok: link-time constant
+}
+
+pub fn is_user_range(p: *const u8, len: usize) -> bool {
+    let start=p as u64;
+    let end=start + (len as u64);
+    end <= image_base() ||
+        start >= image_base() + (unsafe { ENCLAVE_SIZE } as u64) // unsafe ok: link-time constant
+}

src/libstd/sys/sgx/abi/mod.rs

@@ -96,5 +96,5 @@ pub(super) fn exit_with_code(code: isize) -> ! {
             let _ = write!(out, "Exited with status code {}", code);
         }
     }
-    unsafe { usercalls::raw::exit(code != 0) };
+    usercalls::exit(code != 0);
 }