Merge pull request #112 from habnabit/freebsd-kernel-osrng
Use arc4rand(9) on FreeBSD
diff --git a/src/os.rs b/src/os.rs
index fc36012..4cfad6b 100644
--- a/src/os.rs
+++ b/src/os.rs
@@ -11,7 +11,7 @@
//! Interfaces to the operating system provided random number
//! generators.
-use std::io;
+use std::{io, mem};
use Rng;
/// A random number generator that retrieves randomness straight from
@@ -40,18 +40,31 @@
fn fill_bytes(&mut self, v: &mut [u8]) { self.0.fill_bytes(v) }
}
+fn next_u32(mut 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) }
+}
+
+fn next_u64(mut fill_buf: &mut FnMut(&mut [u8])) -> u64 {
+ let mut buf: [u8; 8] = [0; 8];
+ fill_buf(&mut buf);
+ unsafe { mem::transmute::<[u8; 8], u64>(buf) }
+}
+
#[cfg(all(unix, not(target_os = "ios"),
- not(target_os = "nacl")))]
+ not(target_os = "nacl"),
+ not(target_os = "freebsd")))]
mod imp {
extern crate libc;
+ use super::{next_u32, next_u64};
use self::OsRngInner::*;
use std::io;
use std::fs::File;
use Rng;
use read::ReadRng;
- use std::mem;
#[cfg(all(target_os = "linux",
any(target_arch = "x86_64",
@@ -106,18 +119,6 @@
}
}
- fn getrandom_next_u32() -> u32 {
- let mut buf: [u8; 4] = [0u8; 4];
- getrandom_fill_bytes(&mut buf);
- unsafe { mem::transmute::<[u8; 4], u32>(buf) }
- }
-
- fn getrandom_next_u64() -> u64 {
- let mut buf: [u8; 8] = [0u8; 8];
- getrandom_fill_bytes(&mut buf);
- unsafe { mem::transmute::<[u8; 8], u64>(buf) }
- }
-
#[cfg(all(target_os = "linux",
any(target_arch = "x86_64",
target_arch = "x86",
@@ -179,13 +180,13 @@
impl Rng for OsRng {
fn next_u32(&mut self) -> u32 {
match self.inner {
- OsGetrandomRng => getrandom_next_u32(),
+ OsGetrandomRng => next_u32(&mut getrandom_fill_bytes),
OsReadRng(ref mut rng) => rng.next_u32(),
}
}
fn next_u64(&mut self) -> u64 {
match self.inner {
- OsGetrandomRng => getrandom_next_u64(),
+ OsGetrandomRng => next_u64(&mut getrandom_fill_bytes),
OsReadRng(ref mut rng) => rng.next_u64(),
}
}
@@ -202,8 +203,9 @@
mod imp {
extern crate libc;
+ use super::{next_u32, next_u64};
+
use std::io;
- use std::mem;
use Rng;
use self::libc::{c_int, size_t};
@@ -228,14 +230,10 @@
impl Rng for OsRng {
fn next_u32(&mut self) -> u32 {
- let mut v = [0u8; 4];
- self.fill_bytes(&mut v);
- unsafe { mem::transmute(v) }
+ next_u32(&mut |v| self.fill_bytes(v))
}
fn next_u64(&mut self) -> u64 {
- let mut v = [0u8; 8];
- self.fill_bytes(&mut v);
- unsafe { mem::transmute(v) }
+ next_u64(&mut |v| self.fill_bytes(v))
}
fn fill_bytes(&mut self, v: &mut [u8]) {
let ret = unsafe {
@@ -248,13 +246,57 @@
}
}
+#[cfg(target_os = "freebsd")]
+mod imp {
+ extern crate libc;
+
+ use std::{io, ptr};
+ use Rng;
+
+ use super::{next_u32, next_u64};
+
+ pub struct OsRng;
+
+ impl OsRng {
+ pub fn new() -> io::Result<OsRng> {
+ Ok(OsRng)
+ }
+ }
+
+ impl Rng for OsRng {
+ fn next_u32(&mut self) -> u32 {
+ next_u32(&mut |v| self.fill_bytes(v))
+ }
+ fn next_u64(&mut self) -> u64 {
+ next_u64(&mut |v| self.fill_bytes(v))
+ }
+ fn fill_bytes(&mut self, v: &mut [u8]) {
+ let mib = [libc::CTL_KERN, libc::KERN_ARND];
+ // kern.arandom permits a maximum buffer size of 256 bytes
+ for s in v.chunks_mut(256) {
+ let mut s_len = s.len();
+ let ret = unsafe {
+ libc::sysctl(mib.as_ptr(), mib.len() as libc::c_uint,
+ s.as_mut_ptr() as *mut _, &mut s_len,
+ ptr::null(), 0)
+ };
+ if ret == -1 || s_len != s.len() {
+ panic!("kern.arandom sysctl failed! (returned {}, s.len() {}, oldlenp {})",
+ ret, s.len(), s_len);
+ }
+ }
+ }
+ }
+}
+
#[cfg(windows)]
mod imp {
use std::io;
- use std::mem;
use std::ptr;
use Rng;
+ use super::{next_u32, next_u64};
+
type BOOL = i32;
type LPCSTR = *const i8;
type DWORD = u32;
@@ -301,14 +343,10 @@
impl Rng for OsRng {
fn next_u32(&mut self) -> u32 {
- let mut v = [0u8; 4];
- self.fill_bytes(&mut v);
- unsafe { mem::transmute(v) }
+ next_u32(&mut |v| self.fill_bytes(v))
}
fn next_u64(&mut self) -> u64 {
- let mut v = [0u8; 8];
- self.fill_bytes(&mut v);
- unsafe { mem::transmute(v) }
+ next_u64(&mut |v| self.fill_bytes(v))
}
fn fill_bytes(&mut self, v: &mut [u8]) {
// CryptGenRandom takes a DWORD (u32) for the length so we need to
@@ -347,6 +385,8 @@
use std::mem;
use Rng;
+ use super::{next_u32, next_u64};
+
pub struct OsRng(extern fn(dest: *mut libc::c_void,
bytes: libc::size_t,
read: *mut libc::size_t) -> libc::c_int);
@@ -390,14 +430,10 @@
impl Rng for OsRng {
fn next_u32(&mut self) -> u32 {
- let mut v = [0u8; 4];
- self.fill_bytes(&mut v);
- unsafe { mem::transmute(v) }
+ next_u32(&mut |v| self.fill_bytes(v))
}
fn next_u64(&mut self) -> u64 {
- let mut v = [0u8; 8];
- self.fill_bytes(&mut v);
- unsafe { mem::transmute(v) }
+ next_u64(&mut |v| self.fill_bytes(v))
}
fn fill_bytes(&mut self, v: &mut [u8]) {
let mut read = 0;
