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use mem;
use slice;
pub fn hashmap_random_keys() -> (u64, u64) {
let mut v = (0, 0);
unsafe {
let view = slice::from_raw_parts_mut(&mut v as *mut _ as *mut u8,
mem::size_of_val(&v));
imp::fill_bytes(view);
}
return v
}
#[cfg(all(unix,
not(target_os = "ios"),
not(target_os = "openbsd"),
not(target_os = "freebsd"),
not(target_os = "fuchsia")))]
mod imp {
use fs::File;
use io::Read;
use libc;
use sys::os::errno;
#[cfg(any(target_os = "linux", target_os = "android"))]
fn getrandom(buf: &mut [u8]) -> libc::c_long {
unsafe {
libc::syscall(libc::SYS_getrandom, buf.as_mut_ptr(), buf.len(), libc::GRND_NONBLOCK)
}
}
#[cfg(not(any(target_os = "linux", target_os = "android")))]
fn getrandom(_buf: &mut [u8]) -> libc::c_long { -1 }
fn getrandom_fill_bytes(v: &mut [u8]) -> bool {
let mut read = 0;
while read < v.len() {
let result = getrandom(&mut v[read..]);
if result == -1 {
let err = errno() as libc::c_int;
if err == libc::EINTR {
continue;
} else if err == libc::EAGAIN {
return false
} else {
panic!("unexpected getrandom error: {}", err);
}
} else {
read += result as usize;
}
}
return true
}
#[cfg(any(target_os = "linux", target_os = "android"))]
fn is_getrandom_available() -> bool {
use io;
use sync::atomic::{AtomicBool, Ordering};
use sync::Once;
static CHECKER: Once = Once::new();
static AVAILABLE: AtomicBool = AtomicBool::new(false);
CHECKER.call_once(|| {
let mut buf: [u8; 0] = [];
let result = getrandom(&mut buf);
let available = if result == -1 {
let err = io::Error::last_os_error().raw_os_error();
err != Some(libc::ENOSYS)
} else {
true
};
AVAILABLE.store(available, Ordering::Relaxed);
});
AVAILABLE.load(Ordering::Relaxed)
}
#[cfg(not(any(target_os = "linux", target_os = "android")))]
fn is_getrandom_available() -> bool { false }
pub fn fill_bytes(v: &mut [u8]) {
if is_getrandom_available() && getrandom_fill_bytes(v) {
return
}
let mut file = File::open("/dev/urandom")
.expect("failed to open /dev/urandom");
file.read_exact(v).expect("failed to read /dev/urandom");
}
}
#[cfg(target_os = "openbsd")]
mod imp {
use libc;
use sys::os::errno;
pub fn fill_bytes(v: &mut [u8]) {
for s in v.chunks_mut(256) {
let ret = unsafe {
libc::getentropy(s.as_mut_ptr() as *mut libc::c_void, s.len())
};
if ret == -1 {
panic!("unexpected getentropy error: {}", errno());
}
}
}
}
#[cfg(target_os = "ios")]
mod imp {
use io;
use libc::{c_int, size_t};
use ptr;
enum SecRandom {}
#[allow(non_upper_case_globals)]
const kSecRandomDefault: *const SecRandom = ptr::null();
extern {
fn SecRandomCopyBytes(rnd: *const SecRandom,
count: size_t,
bytes: *mut u8) -> c_int;
}
pub fn fill_bytes(v: &mut [u8]) {
let ret = unsafe {
SecRandomCopyBytes(kSecRandomDefault,
v.len(),
v.as_mut_ptr())
};
if ret == -1 {
panic!("couldn't generate random bytes: {}",
io::Error::last_os_error());
}
}
}
#[cfg(target_os = "freebsd")]
mod imp {
use libc;
use ptr;
pub fn fill_bytes(v: &mut [u8]) {
let mib = [libc::CTL_KERN, libc::KERN_ARND];
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(target_os = "fuchsia")]
mod imp {
#[link(name = "zircon")]
extern {
fn zx_cprng_draw(buffer: *mut u8, len: usize, actual: *mut usize) -> i32;
}
fn getrandom(buf: &mut [u8]) -> Result<usize, i32> {
unsafe {
let mut actual = 0;
let status = zx_cprng_draw(buf.as_mut_ptr(), buf.len(), &mut actual);
if status == 0 {
Ok(actual)
} else {
Err(status)
}
}
}
pub fn fill_bytes(v: &mut [u8]) {
let mut buf = v;
while !buf.is_empty() {
let ret = getrandom(buf);
match ret {
Err(err) => {
panic!("kernel zx_cprng_draw call failed! (returned {}, buf.len() {})",
err, buf.len())
}
Ok(actual) => {
let move_buf = buf;
buf = &mut move_buf[(actual as usize)..];
}
}
}
}
}