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author | Daniel Mueller <deso@posteo.net> | 2019-01-16 17:26:30 -0800 |
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committer | Daniel Mueller <deso@posteo.net> | 2019-01-16 17:26:30 -0800 |
commit | 8350ac6afb2d678b74581000a6aafe1994b72231 (patch) | |
tree | 2330da01a806921b3849c9e64d2b9f506495e2c0 /rand/rand_os/src/solaris.rs | |
parent | d6652b913b33e432a748187f9f5623cec1e9926e (diff) | |
download | nitrocli-8350ac6afb2d678b74581000a6aafe1994b72231.tar.gz nitrocli-8350ac6afb2d678b74581000a6aafe1994b72231.tar.bz2 |
Update nitrokey crate to 0.3.3
This change updates the nitrokey crate to version 0.3.3. Along with that
change we update rand to 0.6.4 because rand 0.6.1 does not yet contain a
publicly accessible rand_os. Note that we no longer require all
crates in rand's workspace, but only rand_os and rand_core, which is a
significant reduction in the number of lines of code compiled.
Import subrepo nitrokey/:nitrokey at 7cf747d56ddc0b7eeedc3caf36dcc909907a171c
Import subrepo rand/:rand at 4336232dda03323634b10ec72ddf27914aebc3a2
Diffstat (limited to 'rand/rand_os/src/solaris.rs')
-rw-r--r-- | rand/rand_os/src/solaris.rs | 175 |
1 files changed, 175 insertions, 0 deletions
diff --git a/rand/rand_os/src/solaris.rs b/rand/rand_os/src/solaris.rs new file mode 100644 index 0000000..e8965fd --- /dev/null +++ b/rand/rand_os/src/solaris.rs @@ -0,0 +1,175 @@ +// 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 the Solaris family +//! +//! Read from `/dev/random`, with chunks of limited size (1040 bytes). +//! `/dev/random` uses the Hash_DRBG with SHA512 algorithm from NIST SP 800-90A. +//! `/dev/urandom` uses the FIPS 186-2 algorithm, which is considered less +//! secure. We choose to read from `/dev/random`. +//! +//! Since Solaris 11.3 the `getrandom` syscall is available. To make sure we can +//! compile on both Solaris and on OpenSolaris derivatives, that do not have the +//! function, we do a direct syscall instead of calling a library function. +//! +//! We have no way to differentiate between Solaris, illumos, SmartOS, etc. +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::cmp; + +#[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 }); + } + let open = |p| OpenOptions::new() + .read(true) + .custom_flags(libc::O_NONBLOCK) + .open(p); + random_device::open("/dev/random", &open)?; + 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 chunk_len = cmp::min(1024, dest.len()); + let dest = &mut dest[..chunk_len]; + + match self.method { + OsRngMethod::GetRandom => getrandom_try_fill(dest, blocking)?, + OsRngMethod::RandomDevice => { + if blocking { + info!("OsRng: testing random device /dev/random"); + // We already have a non-blocking handle, but now need a + // blocking one. Not much choice except opening it twice + let mut file = File::open("/dev/random") + .map_err(random_device::map_err)?; + file.read(dest).map_err(random_device::map_err)?; + } else { + self.fill_chunk(dest)?; + } + } + }; + OS_RNG_INITIALIZED.store(true, Ordering::Relaxed); + self.initialized = true; + Ok(chunk_len) + } + + fn max_chunk_size(&self) -> usize { + // The documentation says 1024 is the maximum for getrandom, but + // 1040 for /dev/random. + 1024 + } + + fn method_str(&self) -> &'static str { + match self.method { + OsRngMethod::GetRandom => "getrandom", + OsRngMethod::RandomDevice => "/dev/random", + } + } +} + +fn getrandom(buf: &mut [u8], blocking: bool) -> libc::c_long { + extern "C" { + fn syscall(number: libc::c_long, ...) -> libc::c_long; + } + + const SYS_GETRANDOM: libc::c_long = 143; + const GRND_NONBLOCK: libc::c_uint = 0x0001; + const GRND_RANDOM: libc::c_uint = 0x0002; + + unsafe { + syscall(SYS_GETRANDOM, buf.as_mut_ptr(), buf.len(), + if blocking { 0 } else { GRND_NONBLOCK } | GRND_RANDOM) + } +} + +fn getrandom_try_fill(dest: &mut [u8], blocking: bool) -> Result<(), Error> { + let result = getrandom(dest, blocking); + if result == -1 || result == 0 { + let err = io::Error::last_os_error(); + let kind = err.kind(); + 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 if result != dest.len() as i64 { + return Err(Error::new(ErrorKind::Unavailable, + "unexpected getrandom error")); + } + Ok(()) +} + +fn is_getrandom_available() -> bool { + use std::sync::atomic::{AtomicBool, ATOMIC_BOOL_INIT, Ordering}; + use std::sync::{Once, ONCE_INIT}; + + static CHECKER: Once = ONCE_INIT; + static AVAILABLE: AtomicBool = ATOMIC_BOOL_INIT; + + 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/random" }); + }); + + AVAILABLE.load(Ordering::Relaxed) +} |