proxmox-backup/src/bin/proxmox_client_tools/key_source.rs
Stefan Reiter 9d8ab62769 client-tools: add crypto_parameters_keep_fd
same functionality as crypto_parameters, except it keeps the file
descriptor passed as "keyfd" open (and seeks to the beginning after
reading), if one is given.

Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
2021-04-22 17:55:30 +02:00

586 lines
22 KiB
Rust

use std::convert::TryFrom;
use std::path::PathBuf;
use std::os::unix::io::{FromRawFd, RawFd};
use std::io::Read;
use anyhow::{bail, format_err, Error};
use serde_json::Value;
use proxmox::api::schema::*;
use proxmox::sys::linux::tty;
use proxmox::tools::fs::file_get_contents;
use proxmox_backup::backup::CryptMode;
pub const DEFAULT_ENCRYPTION_KEY_FILE_NAME: &str = "encryption-key.json";
pub const DEFAULT_MASTER_PUBKEY_FILE_NAME: &str = "master-public.pem";
pub const KEYFILE_SCHEMA: Schema =
StringSchema::new("Path to encryption key. All data will be encrypted using this key.")
.schema();
pub const KEYFD_SCHEMA: Schema =
IntegerSchema::new("Pass an encryption key via an already opened file descriptor.")
.minimum(0)
.schema();
pub const MASTER_PUBKEY_FILE_SCHEMA: Schema = StringSchema::new(
"Path to master public key. The encryption key used for a backup will be encrypted using this key and appended to the backup.")
.schema();
pub const MASTER_PUBKEY_FD_SCHEMA: Schema =
IntegerSchema::new("Pass a master public key via an already opened file descriptor.")
.minimum(0)
.schema();
#[derive(Clone, Debug, Eq, PartialEq)]
pub enum KeySource {
DefaultKey,
Fd,
Path(String),
}
pub fn format_key_source(source: &KeySource, key_type: &str) -> String {
match source {
KeySource::DefaultKey => format!("Using default {} key..", key_type),
KeySource::Fd => format!("Using {} key from file descriptor..", key_type),
KeySource::Path(path) => format!("Using {} key from '{}'..", key_type, path),
}
}
#[derive(Clone, Debug, Eq, PartialEq)]
pub struct KeyWithSource {
pub source: KeySource,
pub key: Vec<u8>,
}
impl KeyWithSource {
pub fn from_fd(key: Vec<u8>) -> Self {
Self {
source: KeySource::Fd,
key,
}
}
pub fn from_default(key: Vec<u8>) -> Self {
Self {
source: KeySource::DefaultKey,
key,
}
}
pub fn from_path(path: String, key: Vec<u8>) -> Self {
Self {
source: KeySource::Path(path),
key,
}
}
}
#[derive(Debug, Eq, PartialEq)]
pub struct CryptoParams {
pub mode: CryptMode,
pub enc_key: Option<KeyWithSource>,
// FIXME switch to openssl::rsa::rsa<openssl::pkey::Public> once that is Eq?
pub master_pubkey: Option<KeyWithSource>,
}
pub fn crypto_parameters(param: &Value) -> Result<CryptoParams, Error> {
do_crypto_parameters(param, false)
}
pub fn crypto_parameters_keep_fd(param: &Value) -> Result<CryptoParams, Error> {
do_crypto_parameters(param, true)
}
fn do_crypto_parameters(param: &Value, keep_keyfd_open: bool) -> Result<CryptoParams, Error> {
let keyfile = match param.get("keyfile") {
Some(Value::String(keyfile)) => Some(keyfile),
Some(_) => bail!("bad --keyfile parameter type"),
None => None,
};
let key_fd = match param.get("keyfd") {
Some(Value::Number(key_fd)) => Some(
RawFd::try_from(key_fd
.as_i64()
.ok_or_else(|| format_err!("bad key fd: {:?}", key_fd))?
)
.map_err(|err| format_err!("bad key fd: {:?}: {}", key_fd, err))?
),
Some(_) => bail!("bad --keyfd parameter type"),
None => None,
};
let master_pubkey_file = match param.get("master-pubkey-file") {
Some(Value::String(keyfile)) => Some(keyfile),
Some(_) => bail!("bad --master-pubkey-file parameter type"),
None => None,
};
let master_pubkey_fd = match param.get("master-pubkey-fd") {
Some(Value::Number(key_fd)) => Some(
RawFd::try_from(key_fd
.as_i64()
.ok_or_else(|| format_err!("bad master public key fd: {:?}", key_fd))?
)
.map_err(|err| format_err!("bad public master key fd: {:?}: {}", key_fd, err))?
),
Some(_) => bail!("bad --master-pubkey-fd parameter type"),
None => None,
};
let mode: Option<CryptMode> = match param.get("crypt-mode") {
Some(mode) => Some(serde_json::from_value(mode.clone())?),
None => None,
};
let key = match (keyfile, key_fd) {
(None, None) => None,
(Some(_), Some(_)) => bail!("--keyfile and --keyfd are mutually exclusive"),
(Some(keyfile), None) => Some(KeyWithSource::from_path(
keyfile.clone(),
file_get_contents(keyfile)?,
)),
(None, Some(fd)) => {
let mut input = unsafe { std::fs::File::from_raw_fd(fd) };
let mut data = Vec::new();
let _len: usize = input.read_to_end(&mut data).map_err(|err| {
format_err!("error reading encryption key from fd {}: {}", fd, err)
})?;
if keep_keyfd_open {
// don't close fd if requested, and try to reset seek position
std::mem::forget(input);
unsafe { libc::lseek(fd, 0, libc::SEEK_SET); }
}
Some(KeyWithSource::from_fd(data))
}
};
let master_pubkey = match (master_pubkey_file, master_pubkey_fd) {
(None, None) => None,
(Some(_), Some(_)) => bail!("--keyfile and --keyfd are mutually exclusive"),
(Some(keyfile), None) => Some(KeyWithSource::from_path(
keyfile.clone(),
file_get_contents(keyfile)?,
)),
(None, Some(fd)) => {
let input = unsafe { std::fs::File::from_raw_fd(fd) };
let mut data = Vec::new();
let _len: usize = { input }
.read_to_end(&mut data)
.map_err(|err| format_err!("error reading master key from fd {}: {}", fd, err))?;
Some(KeyWithSource::from_fd(data))
}
};
let res = match mode {
// no crypt mode, enable encryption if keys are available
None => match (key, master_pubkey) {
// only default keys if available
(None, None) => match read_optional_default_encryption_key()? {
None => CryptoParams { mode: CryptMode::None, enc_key: None, master_pubkey: None },
enc_key => {
let master_pubkey = read_optional_default_master_pubkey()?;
CryptoParams {
mode: CryptMode::Encrypt,
enc_key,
master_pubkey,
}
},
},
// explicit master key, default enc key needed
(None, master_pubkey) => match read_optional_default_encryption_key()? {
None => bail!("--master-pubkey-file/--master-pubkey-fd specified, but no key available"),
enc_key => {
CryptoParams {
mode: CryptMode::Encrypt,
enc_key,
master_pubkey,
}
},
},
// explicit keyfile, maybe default master key
(enc_key, None) => CryptoParams { mode: CryptMode::Encrypt, enc_key, master_pubkey: read_optional_default_master_pubkey()? },
// explicit keyfile and master key
(enc_key, master_pubkey) => CryptoParams { mode: CryptMode::Encrypt, enc_key, master_pubkey },
},
// explicitly disabled encryption
Some(CryptMode::None) => match (key, master_pubkey) {
// no keys => OK, no encryption
(None, None) => CryptoParams { mode: CryptMode::None, enc_key: None, master_pubkey: None },
// --keyfile and --crypt-mode=none
(Some(_), _) => bail!("--keyfile/--keyfd and --crypt-mode=none are mutually exclusive"),
// --master-pubkey-file and --crypt-mode=none
(_, Some(_)) => bail!("--master-pubkey-file/--master-pubkey-fd and --crypt-mode=none are mutually exclusive"),
},
// explicitly enabled encryption
Some(mode) => match (key, master_pubkey) {
// no key, maybe master key
(None, master_pubkey) => match read_optional_default_encryption_key()? {
None => bail!("--crypt-mode without --keyfile and no default key file available"),
enc_key => {
eprintln!("Encrypting with default encryption key!");
let master_pubkey = match master_pubkey {
None => read_optional_default_master_pubkey()?,
master_pubkey => master_pubkey,
};
CryptoParams {
mode,
enc_key,
master_pubkey,
}
},
},
// --keyfile and --crypt-mode other than none
(enc_key, master_pubkey) => {
let master_pubkey = match master_pubkey {
None => read_optional_default_master_pubkey()?,
master_pubkey => master_pubkey,
};
CryptoParams { mode, enc_key, master_pubkey }
},
},
};
Ok(res)
}
pub fn find_default_master_pubkey() -> Result<Option<PathBuf>, Error> {
super::find_xdg_file(
DEFAULT_MASTER_PUBKEY_FILE_NAME,
"default master public key file",
)
}
pub fn place_default_master_pubkey() -> Result<PathBuf, Error> {
super::place_xdg_file(
DEFAULT_MASTER_PUBKEY_FILE_NAME,
"default master public key file",
)
}
pub fn find_default_encryption_key() -> Result<Option<PathBuf>, Error> {
super::find_xdg_file(
DEFAULT_ENCRYPTION_KEY_FILE_NAME,
"default encryption key file",
)
}
pub fn place_default_encryption_key() -> Result<PathBuf, Error> {
super::place_xdg_file(
DEFAULT_ENCRYPTION_KEY_FILE_NAME,
"default encryption key file",
)
}
#[cfg(not(test))]
pub(crate) fn read_optional_default_encryption_key() -> Result<Option<KeyWithSource>, Error> {
find_default_encryption_key()?
.map(|path| file_get_contents(path).map(KeyWithSource::from_default))
.transpose()
}
#[cfg(not(test))]
pub(crate) fn read_optional_default_master_pubkey() -> Result<Option<KeyWithSource>, Error> {
find_default_master_pubkey()?
.map(|path| file_get_contents(path).map(KeyWithSource::from_default))
.transpose()
}
#[cfg(test)]
static mut TEST_DEFAULT_ENCRYPTION_KEY: Result<Option<Vec<u8>>, Error> = Ok(None);
#[cfg(test)]
pub(crate) fn read_optional_default_encryption_key() -> Result<Option<KeyWithSource>, Error> {
// not safe when multiple concurrent test cases end up here!
unsafe {
match &TEST_DEFAULT_ENCRYPTION_KEY {
Ok(Some(key)) => Ok(Some(KeyWithSource::from_default(key.clone()))),
Ok(None) => Ok(None),
Err(_) => bail!("test error"),
}
}
}
#[cfg(test)]
// not safe when multiple concurrent test cases end up here!
pub(crate) unsafe fn set_test_encryption_key(value: Result<Option<Vec<u8>>, Error>) {
TEST_DEFAULT_ENCRYPTION_KEY = value;
}
#[cfg(test)]
static mut TEST_DEFAULT_MASTER_PUBKEY: Result<Option<Vec<u8>>, Error> = Ok(None);
#[cfg(test)]
pub(crate) fn read_optional_default_master_pubkey() -> Result<Option<KeyWithSource>, Error> {
// not safe when multiple concurrent test cases end up here!
unsafe {
match &TEST_DEFAULT_MASTER_PUBKEY {
Ok(Some(key)) => Ok(Some(KeyWithSource::from_default(key.clone()))),
Ok(None) => Ok(None),
Err(_) => bail!("test error"),
}
}
}
#[cfg(test)]
// not safe when multiple concurrent test cases end up here!
pub(crate) unsafe fn set_test_default_master_pubkey(value: Result<Option<Vec<u8>>, Error>) {
TEST_DEFAULT_MASTER_PUBKEY = value;
}
pub fn get_encryption_key_password() -> Result<Vec<u8>, Error> {
// fixme: implement other input methods
use std::env::VarError::*;
match std::env::var("PBS_ENCRYPTION_PASSWORD") {
Ok(p) => return Ok(p.as_bytes().to_vec()),
Err(NotUnicode(_)) => bail!("PBS_ENCRYPTION_PASSWORD contains bad characters"),
Err(NotPresent) => {
// Try another method
}
}
// If we're on a TTY, query the user for a password
if tty::stdin_isatty() {
return Ok(tty::read_password("Encryption Key Password: ")?);
}
bail!("no password input mechanism available");
}
#[test]
// WARNING: there must only be one test for crypto_parameters as the default key handling is not
// safe w.r.t. concurrency
fn test_crypto_parameters_handling() -> Result<(), Error> {
use serde_json::json;
use proxmox::tools::fs::{replace_file, CreateOptions};
let some_key = vec![1;1];
let default_key = vec![2;1];
let some_master_key = vec![3;1];
let default_master_key = vec![4;1];
let keypath = "./target/testout/keyfile.test";
let master_keypath = "./target/testout/masterkeyfile.test";
let invalid_keypath = "./target/testout/invalid_keyfile.test";
let no_key_res = CryptoParams {
enc_key: None,
master_pubkey: None,
mode: CryptMode::None,
};
let some_key_res = CryptoParams {
enc_key: Some(KeyWithSource::from_path(
keypath.to_string(),
some_key.clone(),
)),
master_pubkey: None,
mode: CryptMode::Encrypt,
};
let some_key_some_master_res = CryptoParams {
enc_key: Some(KeyWithSource::from_path(
keypath.to_string(),
some_key.clone(),
)),
master_pubkey: Some(KeyWithSource::from_path(
master_keypath.to_string(),
some_master_key.clone(),
)),
mode: CryptMode::Encrypt,
};
let some_key_default_master_res = CryptoParams {
enc_key: Some(KeyWithSource::from_path(
keypath.to_string(),
some_key.clone(),
)),
master_pubkey: Some(KeyWithSource::from_default(default_master_key.clone())),
mode: CryptMode::Encrypt,
};
let some_key_sign_res = CryptoParams {
enc_key: Some(KeyWithSource::from_path(
keypath.to_string(),
some_key.clone(),
)),
master_pubkey: None,
mode: CryptMode::SignOnly,
};
let default_key_res = CryptoParams {
enc_key: Some(KeyWithSource::from_default(default_key.clone())),
master_pubkey: None,
mode: CryptMode::Encrypt,
};
let default_key_sign_res = CryptoParams {
enc_key: Some(KeyWithSource::from_default(default_key.clone())),
master_pubkey: None,
mode: CryptMode::SignOnly,
};
replace_file(&keypath, &some_key, CreateOptions::default())?;
replace_file(&master_keypath, &some_master_key, CreateOptions::default())?;
// no params, no default key == no key
let res = crypto_parameters(&json!({}));
assert_eq!(res.unwrap(), no_key_res);
// keyfile param == key from keyfile
let res = crypto_parameters(&json!({"keyfile": keypath}));
assert_eq!(res.unwrap(), some_key_res);
// crypt mode none == no key
let res = crypto_parameters(&json!({"crypt-mode": "none"}));
assert_eq!(res.unwrap(), no_key_res);
// crypt mode encrypt/sign-only, no keyfile, no default key == Error
assert!(crypto_parameters(&json!({"crypt-mode": "sign-only"})).is_err());
assert!(crypto_parameters(&json!({"crypt-mode": "encrypt"})).is_err());
// crypt mode none with explicit key == Error
assert!(crypto_parameters(&json!({"crypt-mode": "none", "keyfile": keypath})).is_err());
// crypt mode sign-only/encrypt with keyfile == key from keyfile with correct mode
let res = crypto_parameters(&json!({"crypt-mode": "sign-only", "keyfile": keypath}));
assert_eq!(res.unwrap(), some_key_sign_res);
let res = crypto_parameters(&json!({"crypt-mode": "encrypt", "keyfile": keypath}));
assert_eq!(res.unwrap(), some_key_res);
// invalid keyfile parameter always errors
assert!(crypto_parameters(&json!({"keyfile": invalid_keypath})).is_err());
assert!(crypto_parameters(&json!({"keyfile": invalid_keypath, "crypt-mode": "none"})).is_err());
assert!(crypto_parameters(&json!({"keyfile": invalid_keypath, "crypt-mode": "sign-only"})).is_err());
assert!(crypto_parameters(&json!({"keyfile": invalid_keypath, "crypt-mode": "encrypt"})).is_err());
// now set a default key
unsafe { set_test_encryption_key(Ok(Some(default_key.clone()))); }
// and repeat
// no params but default key == default key
let res = crypto_parameters(&json!({}));
assert_eq!(res.unwrap(), default_key_res);
// keyfile param == key from keyfile
let res = crypto_parameters(&json!({"keyfile": keypath}));
assert_eq!(res.unwrap(), some_key_res);
// crypt mode none == no key
let res = crypto_parameters(&json!({"crypt-mode": "none"}));
assert_eq!(res.unwrap(), no_key_res);
// crypt mode encrypt/sign-only, no keyfile, default key == default key with correct mode
let res = crypto_parameters(&json!({"crypt-mode": "sign-only"}));
assert_eq!(res.unwrap(), default_key_sign_res);
let res = crypto_parameters(&json!({"crypt-mode": "encrypt"}));
assert_eq!(res.unwrap(), default_key_res);
// crypt mode none with explicit key == Error
assert!(crypto_parameters(&json!({"crypt-mode": "none", "keyfile": keypath})).is_err());
// crypt mode sign-only/encrypt with keyfile == key from keyfile with correct mode
let res = crypto_parameters(&json!({"crypt-mode": "sign-only", "keyfile": keypath}));
assert_eq!(res.unwrap(), some_key_sign_res);
let res = crypto_parameters(&json!({"crypt-mode": "encrypt", "keyfile": keypath}));
assert_eq!(res.unwrap(), some_key_res);
// invalid keyfile parameter always errors
assert!(crypto_parameters(&json!({"keyfile": invalid_keypath})).is_err());
assert!(crypto_parameters(&json!({"keyfile": invalid_keypath, "crypt-mode": "none"})).is_err());
assert!(crypto_parameters(&json!({"keyfile": invalid_keypath, "crypt-mode": "sign-only"})).is_err());
assert!(crypto_parameters(&json!({"keyfile": invalid_keypath, "crypt-mode": "encrypt"})).is_err());
// now make default key retrieval error
unsafe { set_test_encryption_key(Err(format_err!("test error"))); }
// and repeat
// no params, default key retrieval errors == Error
assert!(crypto_parameters(&json!({})).is_err());
// keyfile param == key from keyfile
let res = crypto_parameters(&json!({"keyfile": keypath}));
assert_eq!(res.unwrap(), some_key_res);
// crypt mode none == no key
let res = crypto_parameters(&json!({"crypt-mode": "none"}));
assert_eq!(res.unwrap(), no_key_res);
// crypt mode encrypt/sign-only, no keyfile, default key error == Error
assert!(crypto_parameters(&json!({"crypt-mode": "sign-only"})).is_err());
assert!(crypto_parameters(&json!({"crypt-mode": "encrypt"})).is_err());
// crypt mode none with explicit key == Error
assert!(crypto_parameters(&json!({"crypt-mode": "none", "keyfile": keypath})).is_err());
// crypt mode sign-only/encrypt with keyfile == key from keyfile with correct mode
let res = crypto_parameters(&json!({"crypt-mode": "sign-only", "keyfile": keypath}));
assert_eq!(res.unwrap(), some_key_sign_res);
let res = crypto_parameters(&json!({"crypt-mode": "encrypt", "keyfile": keypath}));
assert_eq!(res.unwrap(), some_key_res);
// invalid keyfile parameter always errors
assert!(crypto_parameters(&json!({"keyfile": invalid_keypath})).is_err());
assert!(crypto_parameters(&json!({"keyfile": invalid_keypath, "crypt-mode": "none"})).is_err());
assert!(crypto_parameters(&json!({"keyfile": invalid_keypath, "crypt-mode": "sign-only"})).is_err());
assert!(crypto_parameters(&json!({"keyfile": invalid_keypath, "crypt-mode": "encrypt"})).is_err());
// now remove default key again
unsafe { set_test_encryption_key(Ok(None)); }
// set a default master key
unsafe { set_test_default_master_pubkey(Ok(Some(default_master_key.clone()))); }
// and use an explicit master key
assert!(crypto_parameters(&json!({"master-pubkey-file": master_keypath})).is_err());
// just a default == no key
let res = crypto_parameters(&json!({}));
assert_eq!(res.unwrap(), no_key_res);
// keyfile param == key from keyfile
let res = crypto_parameters(&json!({"keyfile": keypath, "master-pubkey-file": master_keypath}));
assert_eq!(res.unwrap(), some_key_some_master_res);
// same with fallback to default master key
let res = crypto_parameters(&json!({"keyfile": keypath}));
assert_eq!(res.unwrap(), some_key_default_master_res);
// crypt mode none == error
assert!(crypto_parameters(&json!({"crypt-mode": "none", "master-pubkey-file": master_keypath})).is_err());
// with just default master key == no key
let res = crypto_parameters(&json!({"crypt-mode": "none"}));
assert_eq!(res.unwrap(), no_key_res);
// crypt mode encrypt without enc key == error
assert!(crypto_parameters(&json!({"crypt-mode": "encrypt", "master-pubkey-file": master_keypath})).is_err());
assert!(crypto_parameters(&json!({"crypt-mode": "encrypt"})).is_err());
// crypt mode none with explicit key == Error
assert!(crypto_parameters(&json!({"crypt-mode": "none", "keyfile": keypath, "master-pubkey-file": master_keypath})).is_err());
assert!(crypto_parameters(&json!({"crypt-mode": "none", "keyfile": keypath})).is_err());
// crypt mode encrypt with keyfile == key from keyfile with correct mode
let res = crypto_parameters(&json!({"crypt-mode": "encrypt", "keyfile": keypath, "master-pubkey-file": master_keypath}));
assert_eq!(res.unwrap(), some_key_some_master_res);
let res = crypto_parameters(&json!({"crypt-mode": "encrypt", "keyfile": keypath}));
assert_eq!(res.unwrap(), some_key_default_master_res);
// invalid master keyfile parameter always errors when a key is passed, even with a valid
// default master key
assert!(crypto_parameters(&json!({"keyfile": keypath, "master-pubkey-file": invalid_keypath})).is_err());
assert!(crypto_parameters(&json!({"keyfile": keypath, "master-pubkey-file": invalid_keypath,"crypt-mode": "none"})).is_err());
assert!(crypto_parameters(&json!({"keyfile": keypath, "master-pubkey-file": invalid_keypath,"crypt-mode": "sign-only"})).is_err());
assert!(crypto_parameters(&json!({"keyfile": keypath, "master-pubkey-file": invalid_keypath,"crypt-mode": "encrypt"})).is_err());
Ok(())
}