Source code
Revision control
Copy as Markdown
Other Tools
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// option. This file may not be copied, modified, or distributed
// except according to those terms.
use std::{
ops::{Deref, DerefMut},
os::raw::c_uint,
ptr::null_mut,
time::{Duration, Instant},
};
use crate::{
err::Res,
ssl::PRFileDesc,
time::{Interval, PRTime, Time},
};
// This is an opaque struct in NSS.
#[allow(clippy::upper_case_acronyms)]
#[allow(clippy::empty_enum)]
pub enum SSLAntiReplayContext {}
experimental_api!(SSL_CreateAntiReplayContext(
now: PRTime,
window: PRTime,
k: c_uint,
bits: c_uint,
ctx: *mut *mut SSLAntiReplayContext,
));
experimental_api!(SSL_ReleaseAntiReplayContext(ctx: *mut SSLAntiReplayContext));
experimental_api!(SSL_SetAntiReplayContext(
fd: *mut PRFileDesc,
ctx: *mut SSLAntiReplayContext,
));
scoped_ptr!(
AntiReplayContext,
SSLAntiReplayContext,
SSL_ReleaseAntiReplayContext
);
/// `AntiReplay` is used by servers when processing 0-RTT handshakes.
/// It limits the exposure of servers to replay attack by rejecting 0-RTT
/// if it appears to be a replay. There is a false-positive rate that can be
/// managed by tuning the parameters used to create the context.
#[allow(clippy::module_name_repetitions)]
pub struct AntiReplay {
ctx: AntiReplayContext,
}
impl AntiReplay {
/// Make a new anti-replay context.
/// See the documentation in NSS for advice on how to set these values.
///
/// # Errors
///
/// Returns an error if `now` is in the past relative to our baseline or
/// NSS is unable to generate an anti-replay context.
pub fn new(now: Instant, window: Duration, k: usize, bits: usize) -> Res<Self> {
let mut ctx: *mut SSLAntiReplayContext = null_mut();
unsafe {
SSL_CreateAntiReplayContext(
Time::from(now).try_into()?,
Interval::from(window).try_into()?,
c_uint::try_from(k)?,
c_uint::try_from(bits)?,
&mut ctx,
)
}?;
Ok(Self {
ctx: AntiReplayContext::from_ptr(ctx)?,
})
}
/// Configure the provided socket with this anti-replay context.
pub(crate) fn config_socket(&self, fd: *mut PRFileDesc) -> Res<()> {
unsafe { SSL_SetAntiReplayContext(fd, *self.ctx) }
}
}