tyler/proxmox-backup
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

debug: recover: allow ignoring missing/corrupt chunks

Browse Source 
replacing them with chunks of zero bytes.

Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
Tested-by: Hannes Laimer <h.laimer@proxmox.com>
This commit is contained in:
Fabian Grünbichler 2022-05-23 16:11:33 +02:00 committed by Thomas Lamprecht
parent 8bec3ff691
commit 53435bc4d5
1 changed files with 84 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

98
src/bin/proxmox_backup_debug/recover.rs
View File

@ -38,7 +38,19 @@ use pbs_tools::crypt_config::CryptConfig;
type: Boolean,
optional: true,
default: false,
}
},
"ignore-missing-chunks": {
description: "If a chunk is missing, warn and write 0-bytes instead to attempt partial recovery.",
type: Boolean,
optional: true,
default: false,
},
"ignore-corrupt-chunks": {
description: "If a chunk is corrupt, warn and write 0-bytes instead to attempt partial recovery.",
type: Boolean,
optional: true,
default: false,
},
}
}
)]
@ -49,6 +61,8 @@ fn recover_index(
chunks: String,
keyfile: Option<String>,
skip_crc: bool,
ignore_missing_chunks: bool,
ignore_corrupt_chunks: bool,
_param: Value,
) -> Result<(), Error> {
let file_path = Path::new(&file);
@ -89,22 +103,78 @@ fn recover_index(
let digest_str = hex::encode(chunk_digest);
let digest_prefix = &digest_str[0..4];
let chunk_path = chunks_path.join(digest_prefix).join(digest_str);
let mut chunk_file = std::fs::File::open(&chunk_path)
.map_err(|e| format_err!("could not open chunk file - {}", e))?;
data.clear();
chunk_file.read_to_end(&mut data)?;
let chunk_blob = DataBlob::from_raw(data.clone())?;
let create_zero_chunk = |msg: String| -> Result<(DataBlob, Option<&[u8; 32]>), Error> {
let info = index
.chunk_info(pos)
.ok_or_else(|| format_err!("Couldn't read chunk info from index at {pos}"))?;
let size = info.size();
if !skip_crc {
chunk_blob.verify_crc()?;
}
eprintln!("WARN: chunk {:?} {}", chunk_path, msg);
eprintln!("WARN: replacing output file {:?} with '\\0'", info.range,);
output_file.write_all(
chunk_blob
.decode(crypt_conf_opt.as_ref(), Some(chunk_digest))?
.as_slice(),
)?;
Ok((
DataBlob::encode(&vec![0; size as usize], crypt_conf_opt.as_ref(), true)?,
None,
))
};
let (chunk_blob, chunk_digest) = match std::fs::File::open(&chunk_path) {
Ok(mut chunk_file) => {
data.clear();
chunk_file.read_to_end(&mut data)?;
// first chance for corrupt chunk - handling magic fails
DataBlob::from_raw(data.clone())
.map(|blob| (blob, Some(chunk_digest)))
.or_else(|err| {
if ignore_corrupt_chunks {
create_zero_chunk(format!("is corrupt - {err}"))
} else {
bail!("{err}");
}
})?
}
Err(err) => {
if ignore_missing_chunks && err.kind() == std::io::ErrorKind::NotFound {
create_zero_chunk(format!("is missing"))?
} else {
bail!("could not open chunk file - {}", err);
}
}
};
// second chance - we need CRC to detect truncated chunks!
let crc_res = if skip_crc {
Ok(())
} else {
chunk_blob.verify_crc()
};
let (chunk_blob, chunk_digest) = if let Err(crc_err) = crc_res {
if ignore_corrupt_chunks {
create_zero_chunk(format!("is corrupt - {crc_err}"))?
} else {
bail!("Error at chunk {:?} - {crc_err}", chunk_path);
}
} else {
(chunk_blob, chunk_digest)
};
// third chance - decoding might fail (digest, compression, encryption)
let decoded = chunk_blob
.decode(crypt_conf_opt.as_ref(), chunk_digest)
.or_else(|err| {
if ignore_corrupt_chunks {
create_zero_chunk(format!("fails to decode - {err}"))?
.0
.decode(crypt_conf_opt.as_ref(), None)
} else {
bail!("Failed to decode chunk {:?} = {}", chunk_path, err);
}
})?;
output_file.write_all(decoded.as_slice())?;
}
Ok(())