src/auth_helpers.rs

   1 use anyhow::{bail, format_err, Error};
   2 use lazy_static::lazy_static;
   3
   4 use openssl::rsa::{Rsa};
   5 use openssl::pkey::{PKey, Public, Private};
   6 use openssl::sha;
   7
   8 use std::path::PathBuf;
   9
  10 use proxmox::tools::fs::{file_get_contents, replace_file, CreateOptions};
  11 use proxmox::try_block;
  12
  13 use crate::api2::types::Userid;
  14
  15 fn compute_csrf_secret_digest(
  16     timestamp: i64,
  17     secret: &[u8],
  18     userid: &Userid,
  19 ) -> String {
  20
  21     let mut hasher = sha::Sha256::new();
  22     let data = format!("{:08X}:{}:", timestamp, userid);
  23     hasher.update(data.as_bytes());
  24     hasher.update(secret);
  25
  26     base64::encode_config(&hasher.finish(), base64::STANDARD_NO_PAD)
  27 }
  28
  29 pub fn assemble_csrf_prevention_token(
  30     secret: &[u8],
  31     userid: &Userid,
  32 ) -> String {
  33
  34     let epoch = proxmox::tools::time::epoch_i64();
  35
  36     let digest = compute_csrf_secret_digest(epoch, secret, userid);
  37
  38     format!("{:08X}:{}", epoch, digest)
  39 }
  40
  41 pub fn verify_csrf_prevention_token(
  42     secret: &[u8],
  43     userid: &Userid,
  44     token: &str,
  45     min_age: i64,
  46     max_age: i64,
  47 ) -> Result<i64, Error> {
  48
  49     use std::collections::VecDeque;
  50
  51     let mut parts: VecDeque<&str> = token.split(':').collect();
  52
  53     try_block!({
  54
  55         if parts.len() != 2 {
  56             bail!("format error - wrong number of parts.");
  57         }
  58
  59         let timestamp = parts.pop_front().unwrap();
  60         let sig = parts.pop_front().unwrap();
  61
  62         let ttime = i64::from_str_radix(timestamp, 16).
  63             map_err(|err| format_err!("timestamp format error - {}", err))?;
  64
  65         let digest = compute_csrf_secret_digest(ttime, secret, userid);
  66
  67         if digest != sig {
  68             bail!("invalid signature.");
  69         }
  70
  71         let now = proxmox::tools::time::epoch_i64();
  72
  73         let age = now - ttime;
  74         if age < min_age {
  75             bail!("timestamp newer than expected.");
  76         }
  77
  78         if age > max_age {
  79             bail!("timestamp too old.");
  80         }
  81
  82         Ok(age)
  83     }).map_err(|err| format_err!("invalid csrf token - {}", err))
  84 }
  85
  86 pub fn generate_csrf_key() -> Result<(), Error> {
  87
  88     let path = PathBuf::from(configdir!("/csrf.key"));
  89
  90     if path.exists() { return Ok(()); }
  91
  92     let rsa = Rsa::generate(2048).unwrap();
  93
  94     let pem = rsa.private_key_to_pem()?;
  95
  96     use nix::sys::stat::Mode;
  97
  98     let backup_user = crate::backup::backup_user()?;
  99
 100     replace_file(
 101         &path,
 102         &pem,
 103         CreateOptions::new()
 104             .perm(Mode::from_bits_truncate(0o0640))
 105             .owner(nix::unistd::ROOT)
 106             .group(backup_user.gid),
 107     )?;
 108
 109     Ok(())
 110 }
 111
 112 pub fn generate_auth_key() -> Result<(), Error> {
 113
 114     let priv_path = PathBuf::from(configdir!("/authkey.key"));
 115
 116     let mut public_path = priv_path.clone();
 117     public_path.set_extension("pub");
 118
 119     if priv_path.exists() && public_path.exists() { return Ok(()); }
 120
 121     let rsa = Rsa::generate(4096).unwrap();
 122
 123     let priv_pem = rsa.private_key_to_pem()?;
 124
 125     use nix::sys::stat::Mode;
 126
 127     replace_file(
 128         &priv_path, &priv_pem, CreateOptions::new().perm(Mode::from_bits_truncate(0o0600)))?;
 129
 130     let public_pem = rsa.public_key_to_pem()?;
 131
 132     let backup_user = crate::backup::backup_user()?;
 133
 134     replace_file(
 135         &public_path,
 136         &public_pem,
 137         CreateOptions::new()
 138             .perm(Mode::from_bits_truncate(0o0640))
 139             .owner(nix::unistd::ROOT)
 140             .group(backup_user.gid),
 141     )?;
 142
 143     Ok(())
 144 }
 145
 146 pub fn csrf_secret() -> &'static [u8] {
 147
 148     lazy_static! {
 149         static ref SECRET: Vec<u8> =
 150             file_get_contents(configdir!("/csrf.key")).unwrap();
 151     }
 152
 153     &SECRET
 154 }
 155
 156 fn load_private_auth_key() -> Result<PKey<Private>, Error> {
 157
 158     let pem = file_get_contents(configdir!("/authkey.key"))?;
 159     let rsa = Rsa::private_key_from_pem(&pem)?;
 160     let key = PKey::from_rsa(rsa)?;
 161
 162     Ok(key)
 163 }
 164
 165 pub fn private_auth_key() -> &'static PKey<Private> {
 166
 167     lazy_static! {
 168         static ref KEY: PKey<Private> = load_private_auth_key().unwrap();
 169     }
 170
 171     &KEY
 172 }
 173
 174 fn load_public_auth_key() -> Result<PKey<Public>, Error> {
 175
 176     let pem = file_get_contents(configdir!("/authkey.pub"))?;
 177     let rsa = Rsa::public_key_from_pem(&pem)?;
 178     let key = PKey::from_rsa(rsa)?;
 179
 180     Ok(key)
 181 }
 182
 183 pub fn public_auth_key() -> &'static PKey<Public> {
 184
 185     lazy_static! {
 186         static ref KEY: PKey<Public> = load_public_auth_key().unwrap();
 187     }
 188
 189     &KEY
 190 }