| //! Implementation for the Solaris family |
| //! |
| //! `/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` (and use GRND_RANDOM). |
| //! |
| //! Solaris 11.3 and late-2018 illumos added the getrandom(2) libc function. |
| //! To make sure we can compile on both Solaris and its derivatives, as well as |
| //! function, we check for the existence of getrandom(2) in libc by calling |
| //! libc::dlsym. |
| use crate::{ |
| use_file, |
| util_libc::{sys_fill_exact, Weak}, |
| Error, |
| }; |
| use core::mem::{self, MaybeUninit}; |
| |
| static GETRANDOM: Weak = unsafe { Weak::new("getrandom\0") }; |
| type GetRandomFn = |
| unsafe extern "C" fn(*mut libc::c_void, libc::size_t, libc::c_uint) -> libc::ssize_t; |
| |
| pub fn getrandom_inner(dest: &mut [MaybeUninit<u8>]) -> Result<(), Error> { |
| if let Some(fptr) = GETRANDOM.ptr() { |
| let func: GetRandomFn = unsafe { mem::transmute(fptr) }; |
| // 256 bytes is the lowest common denominator across all the Solaris |
| // derived platforms for atomically obtaining random data. |
| for chunk in dest.chunks_mut(256) { |
| sys_fill_exact(chunk, |buf| unsafe { |
| // A cast is needed for the flags as libc uses the wrong type. |
| func( |
| buf.as_mut_ptr() as *mut libc::c_void, |
| buf.len(), |
| libc::GRND_RANDOM as libc::c_uint, |
| ) |
| })? |
| } |
| Ok(()) |
| } else { |
| use_file::getrandom_inner(dest) |
| } |
| } |