fix #3139: add key fingerprint to manifest

if the manifest is signed/the contained archives/blobs are encrypted.
stored in 'unprotected' area, since there is already a strong binding
between key and manifest via the signature, and this avoids breaking
backwards compatibility for a simple usability improvement.

Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
This commit is contained in:
Fabian Grünbichler 2020-11-20 17:38:35 +01:00 committed by Dietmar Maurer
parent 5e17dbf2bb
commit 6b127e6ea0
1 changed files with 37 additions and 1 deletions

View File

@ -5,7 +5,7 @@ use std::path::Path;
use serde_json::{json, Value};
use ::serde::{Deserialize, Serialize};
use crate::backup::{BackupDir, CryptMode, CryptConfig};
use crate::backup::{BackupDir, CryptMode, CryptConfig, Fingerprint};
pub const MANIFEST_BLOB_NAME: &str = "index.json.blob";
pub const MANIFEST_LOCK_NAME: &str = ".index.json.lck";
@ -223,12 +223,48 @@ impl BackupManifest {
if let Some(crypt_config) = crypt_config {
let sig = self.signature(crypt_config)?;
manifest["signature"] = proxmox::tools::digest_to_hex(&sig).into();
let fingerprint = &crypt_config.fingerprint();
manifest["unprotected"]["key-fingerprint"] = serde_json::to_value(fingerprint)?;
}
let manifest = serde_json::to_string_pretty(&manifest).unwrap().into();
Ok(manifest)
}
pub fn fingerprint(&self) -> Result<Option<Fingerprint>, Error> {
match &self.unprotected["key-fingerprint"] {
Value::Null => Ok(None),
value => Ok(Some(serde_json::from_value(value.clone())?))
}
}
/// Checks if a BackupManifest and a CryptConfig share a valid fingerprint combination.
///
/// An unsigned manifest is valid with any or no CryptConfig.
/// A signed manifest is only valid with a matching CryptConfig.
pub fn check_fingerprint(&self, crypt_config: Option<&CryptConfig>) -> Result<(), Error> {
if let Some(fingerprint) = self.fingerprint()? {
match crypt_config {
None => bail!(
"missing key - manifest was created with key {}",
fingerprint,
),
Some(crypt_config) => {
let config_fp = crypt_config.fingerprint();
if config_fp != fingerprint {
bail!(
"wrong key - manifest's key {} does not match provided key {}",
fingerprint,
config_fp
);
}
}
}
};
Ok(())
}
/// Try to read the manifest. This verifies the signature if there is a crypt_config.
pub fn from_data(data: &[u8], crypt_config: Option<&CryptConfig>) -> Result<BackupManifest, Error> {
let json: Value = serde_json::from_slice(data)?;