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Diffstat (limited to 'rand/rand_os/src/linux_android.rs')
| -rw-r--r-- | rand/rand_os/src/linux_android.rs | 182 |
1 files changed, 0 insertions, 182 deletions
diff --git a/rand/rand_os/src/linux_android.rs b/rand/rand_os/src/linux_android.rs deleted file mode 100644 index 9622f93..0000000 --- a/rand/rand_os/src/linux_android.rs +++ /dev/null @@ -1,182 +0,0 @@ -// Copyright 2018 Developers of the Rand project. -// -// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or -// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license -// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your -// option. This file may not be copied, modified, or distributed -// except according to those terms. - -//! Implementation for Linux / Android - -extern crate libc; - -use rand_core::{Error, ErrorKind}; -use super::random_device; -use super::OsRngImpl; - -use std::io; -use std::io::Read; -use std::fs::{File, OpenOptions}; -use std::os::unix::fs::OpenOptionsExt; -use std::sync::atomic::{AtomicBool, ATOMIC_BOOL_INIT, Ordering}; -use std::sync::{Once, ONCE_INIT}; - -#[derive(Clone, Debug)] -pub struct OsRng { - method: OsRngMethod, - initialized: bool, -} - -#[derive(Clone, Debug)] -enum OsRngMethod { - GetRandom, - RandomDevice, -} - -impl OsRngImpl for OsRng { - fn new() -> Result<OsRng, Error> { - if is_getrandom_available() { - return Ok(OsRng { method: OsRngMethod::GetRandom, - initialized: false }); - } - random_device::open("/dev/urandom", &|p| File::open(p))?; - Ok(OsRng { method: OsRngMethod::RandomDevice, initialized: false }) - } - - fn fill_chunk(&mut self, dest: &mut [u8]) -> Result<(), Error> { - match self.method { - OsRngMethod::GetRandom => getrandom_try_fill(dest, false), - OsRngMethod::RandomDevice => random_device::read(dest), - } - } - - fn test_initialized(&mut self, dest: &mut [u8], blocking: bool) - -> Result<usize, Error> - { - static OS_RNG_INITIALIZED: AtomicBool = ATOMIC_BOOL_INIT; - if !self.initialized { - self.initialized = OS_RNG_INITIALIZED.load(Ordering::Relaxed); - } - if self.initialized { return Ok(0); } - - let result = match self.method { - OsRngMethod::GetRandom => { - getrandom_try_fill(dest, blocking)?; - Ok(dest.len()) - } - OsRngMethod::RandomDevice => { - info!("OsRng: testing random device /dev/random"); - let mut file = OpenOptions::new() - .read(true) - .custom_flags(if blocking { 0 } else { libc::O_NONBLOCK }) - .open("/dev/random") - .map_err(random_device::map_err)?; - file.read(&mut dest[..1]).map_err(random_device::map_err)?; - Ok(1) - } - }; - OS_RNG_INITIALIZED.store(true, Ordering::Relaxed); - self.initialized = true; - result - } - - fn method_str(&self) -> &'static str { - match self.method { - OsRngMethod::GetRandom => "getrandom", - OsRngMethod::RandomDevice => "/dev/urandom", - } - } -} - -#[cfg(target_arch = "x86_64")] -const NR_GETRANDOM: libc::c_long = 318; -#[cfg(target_arch = "x86")] -const NR_GETRANDOM: libc::c_long = 355; -#[cfg(target_arch = "arm")] -const NR_GETRANDOM: libc::c_long = 384; -#[cfg(target_arch = "aarch64")] -const NR_GETRANDOM: libc::c_long = 278; - #[cfg(target_arch = "s390x")] -const NR_GETRANDOM: libc::c_long = 349; -#[cfg(target_arch = "powerpc")] -const NR_GETRANDOM: libc::c_long = 359; -#[cfg(target_arch = "powerpc64")] -const NR_GETRANDOM: libc::c_long = 359; -#[cfg(target_arch = "mips")] // old ABI -const NR_GETRANDOM: libc::c_long = 4353; -#[cfg(target_arch = "mips64")] -const NR_GETRANDOM: libc::c_long = 5313; -#[cfg(target_arch = "sparc")] -const NR_GETRANDOM: libc::c_long = 347; -#[cfg(target_arch = "sparc64")] -const NR_GETRANDOM: libc::c_long = 347; -#[cfg(not(any(target_arch = "x86_64", target_arch = "x86", - target_arch = "arm", target_arch = "aarch64", - target_arch = "s390x", target_arch = "powerpc", - target_arch = "powerpc64", target_arch = "mips", - target_arch = "mips64", target_arch = "sparc", - target_arch = "sparc64")))] -const NR_GETRANDOM: libc::c_long = 0; - -fn getrandom(buf: &mut [u8], blocking: bool) -> libc::c_long { - const GRND_NONBLOCK: libc::c_uint = 0x0001; - - if NR_GETRANDOM == 0 { return -1 }; - - unsafe { - libc::syscall(NR_GETRANDOM, buf.as_mut_ptr(), buf.len(), - if blocking { 0 } else { GRND_NONBLOCK }) - } -} - -fn getrandom_try_fill(dest: &mut [u8], blocking: bool) -> Result<(), Error> { - let mut read = 0; - while read < dest.len() { - let result = getrandom(&mut dest[read..], blocking); - if result == -1 { - let err = io::Error::last_os_error(); - let kind = err.kind(); - if kind == io::ErrorKind::Interrupted { - continue; - } else if kind == io::ErrorKind::WouldBlock { - return Err(Error::with_cause( - ErrorKind::NotReady, - "getrandom not ready", - err, - )); - } else { - return Err(Error::with_cause( - ErrorKind::Unavailable, - "unexpected getrandom error", - err, - )); - } - } else { - read += result as usize; - } - } - Ok(()) -} - -fn is_getrandom_available() -> bool { - static CHECKER: Once = ONCE_INIT; - static AVAILABLE: AtomicBool = ATOMIC_BOOL_INIT; - - if NR_GETRANDOM == 0 { return false }; - - CHECKER.call_once(|| { - debug!("OsRng: testing getrandom"); - let mut buf: [u8; 0] = []; - let result = getrandom(&mut buf, false); - 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); - info!("OsRng: using {}", if available { "getrandom" } else { "/dev/urandom" }); - }); - - AVAILABLE.load(Ordering::Relaxed) -} |