Revert "auth: 'crypt' is not thread safe"

With this I'm getting coredumps on every log in:

> Process 20957 (proxmox-backup-) of user 34 dumped core.
>
> Stack trace of thread 20987:
> #0  0x0000563dec9ac37f _ZN3std3sys4unix14stack_overflow3imp14signal_handler17ha95ed06a038ca319E.llvm.11547235952357801165 (proxmox-backup-proxy)
> #1  0x00007f2638de9840 __restore_rt (libc.so.6)
> #2  0x00007f2638e51dac __stpncpy_sse2_unaligned (libc.so.6)
> #3  0x00007f26393b1340 __sha256_crypt_r (libcrypt.so.1)
> #4  0x00007f26393b0553 __crypt_r (libcrypt.so.1)
> #5  0x0000563dec6e44df _ZN14proxmox_backup4auth5crypt17hd5165f960093dfe7E (proxmox-backup-proxy)

This reverts commit acefa2bb6e.
This commit is contained in:
Thomas Lamprecht 2021-07-26 16:38:16 +02:00
parent 3841301ee9
commit 94f6127711

View File

@ -4,7 +4,7 @@
use std::process::{Command, Stdio};
use std::io::Write;
use std::ffi::CStr;
use std::ffi::{CString, CStr};
use anyhow::{bail, format_err, Error};
use serde_json::json;
@ -70,51 +70,24 @@ impl ProxmoxAuthenticator for PAM {
pub struct PBS();
// from libcrypt1, 'lib/crypt.h.in'
const CRYPT_OUTPUT_SIZE: usize = 384;
const CRYPT_MAX_PASSPHRASE_SIZE: usize = 512;
const CRYPT_DATA_RESERVED_SIZE: usize = 767;
const CRYPT_DATA_INTERNAL_SIZE: usize = 30720;
pub fn crypt(password: &[u8], salt: &str) -> Result<String, Error> {
#[repr(C)]
struct crypt_data {
output: [libc::c_char; CRYPT_OUTPUT_SIZE],
setting: [libc::c_char; CRYPT_OUTPUT_SIZE],
input: [libc::c_char; CRYPT_MAX_PASSPHRASE_SIZE],
reserved: [libc::c_char; CRYPT_DATA_RESERVED_SIZE],
initialized: libc::c_char,
internal: [libc::c_char; CRYPT_DATA_INTERNAL_SIZE],
}
pub fn crypt(password: &[u8], salt: &[u8]) -> Result<String, Error> {
#[link(name = "crypt")]
#[link(name="crypt")]
extern "C" {
#[link_name = "crypt_r"]
fn __crypt_r(
key: *const libc::c_char,
salt: *const libc::c_char,
data: *mut crypt_data,
) -> *mut libc::c_char;
#[link_name = "crypt"]
fn __crypt(key: *const libc::c_char, salt: *const libc::c_char) -> * mut libc::c_char;
}
let mut data: crypt_data = unsafe { std::mem::zeroed() };
for (i, c) in salt.iter().take(data.setting.len() - 1).enumerate() {
data.setting[i] = *c as libc::c_char;
}
for (i, c) in password.iter().take(data.input.len() - 1).enumerate() {
data.input[i] = *c as libc::c_char;
}
let salt = CString::new(salt)?;
let password = CString::new(password)?;
let res = unsafe {
let status = __crypt_r(
&data.input as *const _,
&data.setting as *const _,
&mut data as *mut _,
);
if status.is_null() {
bail!("internal error: crypt_r returned null pointer");
}
CStr::from_ptr(&data.output as *const _)
CStr::from_ptr(
__crypt(
password.as_c_str().as_ptr(),
salt.as_c_str().as_ptr()
)
)
};
Ok(String::from(res.to_str()?))
}
@ -125,11 +98,11 @@ pub fn encrypt_pw(password: &str) -> Result<String, Error> {
let salt = proxmox::sys::linux::random_data(8)?;
let salt = format!("$5${}$", base64::encode_config(&salt, base64::CRYPT));
crypt(password.as_bytes(), salt.as_bytes())
crypt(password.as_bytes(), &salt)
}
pub fn verify_crypt_pw(password: &str, enc_password: &str) -> Result<(), Error> {
let verify = crypt(password.as_bytes(), enc_password.as_bytes())?;
let verify = crypt(password.as_bytes(), enc_password)?;
if verify != enc_password {
bail!("invalid credentials");
}