Revision control

Copy as Markdown

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
use crate::util::{ensure_nss_initialized, map_nss_secstatus, sec_item_as_slice, ScopedPtr};
use crate::{
error::*,
pk11::{
slot::get_internal_slot,
types::{AlgorithmID, SymKey},
},
};
// Expose for consumers to choose the hashing algorithm
// Currently only SHA256 supported
pub use crate::pk11::context::HashAlgorithm;
use nss_sys::SECOidTag;
// ***** BASED ON THE FOLLOWING IMPLEMENTATION *****
pub fn pbkdf2_key_derive(
password: &[u8],
salt: &[u8],
iterations: u32,
hash_algorithm: HashAlgorithm,
out: &mut [u8],
) -> Result<()> {
ensure_nss_initialized();
let oid_tag = match hash_algorithm {
HashAlgorithm::SHA256 => SECOidTag::SEC_OID_HMAC_SHA256 as u32,
HashAlgorithm::SHA384 => SECOidTag::SEC_OID_HMAC_SHA384 as u32,
};
let mut sec_salt = nss_sys::SECItem {
len: u32::try_from(salt.len())?,
data: salt.as_ptr() as *mut u8,
type_: 0,
};
let alg_id = unsafe {
AlgorithmID::from_ptr(nss_sys::PK11_CreatePBEV2AlgorithmID(
SECOidTag::SEC_OID_PKCS5_PBKDF2 as u32,
SECOidTag::SEC_OID_HMAC_SHA1 as u32,
oid_tag,
i32::try_from(out.len())?,
i32::try_from(iterations)?,
&mut sec_salt as *mut nss_sys::SECItem,
))?
};
let slot = get_internal_slot()?;
let mut sec_pw = nss_sys::SECItem {
len: u32::try_from(password.len())?,
data: password.as_ptr() as *mut u8,
type_: 0,
};
let sym_key = unsafe {
SymKey::from_ptr(nss_sys::PK11_PBEKeyGen(
slot.as_mut_ptr(),
alg_id.as_mut_ptr(),
&mut sec_pw as *mut nss_sys::SECItem,
nss_sys::PR_FALSE,
std::ptr::null_mut(),
))?
};
map_nss_secstatus(|| unsafe { nss_sys::PK11_ExtractKeyValue(sym_key.as_mut_ptr()) })?;
// This doesn't leak, because the SECItem* returned by PK11_GetKeyData
// just refers to a buffer managed by `sym_key` which we copy into `buf`
let mut key_data = unsafe { *nss_sys::PK11_GetKeyData(sym_key.as_mut_ptr()) };
let buf = unsafe { sec_item_as_slice(&mut key_data)? };
// Stop panic in swap_with_slice by returning an error if the sizes mismatch
if buf.len() != out.len() {
return Err(ErrorKind::InternalError.into());
}
out.swap_with_slice(buf);
Ok(())
}