| // Copyright (C) 2018-2019, Cloudflare, Inc. |
| // All rights reserved. |
| // |
| // Redistribution and use in source and binary forms, with or without |
| // modification, are permitted provided that the following conditions are |
| // met: |
| // |
| // * Redistributions of source code must retain the above copyright notice, |
| // this list of conditions and the following disclaimer. |
| // |
| // * Redistributions in binary form must reproduce the above copyright |
| // notice, this list of conditions and the following disclaimer in the |
| // documentation and/or other materials provided with the distribution. |
| // |
| // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS |
| // IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, |
| // THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| // PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR |
| // CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
| // EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
| // PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
| // PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF |
| // LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING |
| // NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS |
| // SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| |
| pub fn rand_bytes(buf: &mut [u8]) { |
| unsafe { |
| RAND_bytes(buf.as_mut_ptr(), buf.len()); |
| } |
| } |
| |
| pub fn rand_u8() -> u8 { |
| let mut buf = [0; 1]; |
| |
| rand_bytes(&mut buf); |
| |
| buf[0] |
| } |
| |
| pub fn rand_u64() -> u64 { |
| let mut buf = [0; 8]; |
| |
| rand_bytes(&mut buf); |
| |
| u64::from_ne_bytes(buf) |
| } |
| |
| pub fn rand_u64_uniform(max: u64) -> u64 { |
| let chunk_size = u64::max_value() / max; |
| let end_of_last_chunk = chunk_size * max; |
| |
| let mut r = rand_u64(); |
| |
| while r >= end_of_last_chunk { |
| r = rand_u64(); |
| } |
| |
| r / chunk_size |
| } |
| |
| extern { |
| fn RAND_bytes(buf: *mut u8, len: libc::size_t) -> libc::c_int; |
| } |