Add support for x86_64-fortanix-unknown-sgx target

CHANGELOG.md

@@ -4,6 +4,10 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
+## [0.4.4] - 2018-01-06
+### Added
+- SGX support
+
 ## [0.4.3] - 2018-08-16
 ### Fixed
 - Use correct syscall number for PowerPC (#589)

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "rand"
-version = "0.4.3"
+version = "0.4.4"
 authors = ["The Rust Project Developers"]
 license = "MIT/Apache-2.0"
 readme = "README.md"
@@ -33,3 +33,7 @@ members = ["rand-derive"]
 
 [target.'cfg(target_os = "fuchsia")'.dependencies]
 fuchsia-zircon = "0.3.2"
+
+[target.'cfg(target_env = "sgx")'.dependencies]
+rdrand = "0.4.0"
+rand_core = "0.3.0"

src/lib.rs

@@ -250,6 +250,12 @@
 #[cfg(feature="std")] extern crate std as core;
 #[cfg(all(feature = "alloc", not(feature="std")))] extern crate alloc;
 
+#[cfg(target_env = "sgx")]
+extern crate rdrand;
+
+#[cfg(target_env = "sgx")]
+extern crate rand_core;
+
 use core::marker;
 use core::mem;
 #[cfg(feature="std")] use std::cell::RefCell;

src/os.rs

@@ -11,7 +11,11 @@
 //! Interfaces to the operating system provided random number
 //! generators.
 
-use std::{io, mem, fmt};
+use std::{io, fmt};
+
+#[cfg(not(target_env = "sgx"))]
+use std::mem;
+
 use Rng;
 
 /// A random number generator that retrieves randomness straight from
@@ -53,12 +57,14 @@ impl fmt::Debug for OsRng {
     }
 }
 
+#[cfg(not(target_env = "sgx"))]
 fn next_u32(fill_buf: &mut FnMut(&mut [u8])) -> u32 {
     let mut buf: [u8; 4] = [0; 4];
     fill_buf(&mut buf);
     unsafe { mem::transmute::<[u8; 4], u32>(buf) }
 }
 
+#[cfg(not(target_env = "sgx"))]
 fn next_u64(fill_buf: &mut FnMut(&mut [u8])) -> u64 {
     let mut buf: [u8; 8] = [0; 8];
     fill_buf(&mut buf);
@@ -562,6 +568,47 @@ mod imp {
     }
 }
 
+#[cfg(target_env = "sgx")]
+mod imp {
+    use rdrand::RdRand;
+    use std::io;
+    use rand_core::RngCore;
+
+    pub struct OsRng{
+        gen: RdRand
+    }
+
+    impl OsRng {
+        pub fn new() -> io::Result<OsRng> {
+            match RdRand::new() {
+                Ok(rng) => Ok(OsRng { gen: rng }),
+                Err(_) => Err(io::Error::new(io::ErrorKind::Other, "Not supported"))
+            }
+        }
+
+        pub(crate) fn next_u32(&mut self) -> u32 {
+            match self.gen.try_next_u32() {
+                Some(n) => n,
+                None => panic!("Non-recoverable hardware failure has occured")
+            }
+        }
+
+        pub(crate) fn next_u64(&mut self) -> u64 {
+            match self.gen.try_next_u64() {
+                Some(n) => n,
+                None => panic!("Non-recoverable hardware failure has occured")
+            }
+        }
+
+        pub(crate) fn fill_bytes(&mut self, v: &mut [u8]) {
+            match self.gen.try_fill_bytes(v) {
+                Ok(_) => {},
+                Err(_) => panic!("Non-recoverable hardware failure has occured")
+            }
+        }
+    }
+}
+
 #[cfg(test)]
 mod test {
     use std::sync::mpsc::channel;