From: Shannon Sterz <s.sterz@proxmox.com>
To: pbs-devel@lists.proxmox.com
Subject: [pbs-devel] [PATCH proxmox-backup] auth: add locking to `PbsAuthenticator` to avoid race conditions
Date: Thu, 23 May 2024 13:25:59 +0200 [thread overview]
Message-ID: <20240523112559.257547-1-s.sterz@proxmox.com> (raw)
currently we don't lock the shadow file when removing or storing a
password. by adding locking here we avoid a situation where storing
and/or removing a password concurrently could lead to a race
condition. in this scenario it is possible that a password isn't
persisted or a password isn't removed. we already do this for
the "token.shadow" file, so just use the same mechanism here.
Signed-off-by: Shannon Sterz <s.sterz@proxmox.com>
---
src/auth.rs | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/src/auth.rs b/src/auth.rs
index 21468d4b..5134e41e 100644
--- a/src/auth.rs
+++ b/src/auth.rs
@@ -9,6 +9,7 @@ use std::pin::Pin;
use anyhow::{bail, Error};
use futures::Future;
use once_cell::sync::{Lazy, OnceCell};
+use pbs_config::open_backup_lockfile;
use proxmox_router::http_bail;
use serde_json::json;
@@ -31,6 +32,7 @@ pub const TERM_PREFIX: &str = "PBSTERM";
struct PbsAuthenticator;
pub(crate) const SHADOW_CONFIG_FILENAME: &str = configdir!("/shadow.json");
+pub(crate) const SHADOW_LOCK_FILENAME: &str = configdir!("/shadow.json.lock");
impl Authenticator for PbsAuthenticator {
fn authenticate_user<'a>(
@@ -69,6 +71,8 @@ impl Authenticator for PbsAuthenticator {
_client_ip: Option<&IpAddr>,
) -> Result<(), Error> {
let enc_password = proxmox_sys::crypt::encrypt_pw(password)?;
+
+ let _guard = open_backup_lockfile(SHADOW_LOCK_FILENAME, None, true);
let mut data = proxmox_sys::fs::file_get_json(SHADOW_CONFIG_FILENAME, Some(json!({})))?;
data[username.as_str()] = enc_password.into();
@@ -85,6 +89,8 @@ impl Authenticator for PbsAuthenticator {
}
fn remove_password(&self, username: &UsernameRef) -> Result<(), Error> {
+ let _guard = open_backup_lockfile(SHADOW_LOCK_FILENAME, None, true);
+
let mut data = proxmox_sys::fs::file_get_json(SHADOW_CONFIG_FILENAME, Some(json!({})))?;
if let Some(map) = data.as_object_mut() {
map.remove(username.as_str());
--
2.39.2
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next reply other threads:[~2024-05-23 11:25 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-05-23 11:25 Shannon Sterz [this message]
2024-05-23 11:46 ` Gabriel Goller
2024-05-23 12:06 ` Shannon Sterz
2024-06-03 9:00 ` Wolfgang Bumiller
2024-06-03 9:12 ` Gabriel Goller
2024-06-03 9:02 ` [pbs-devel] applied: " Wolfgang Bumiller
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