diff --git a/seaweed-volume/proto/volume_server.proto b/seaweed-volume/proto/volume_server.proto
index 8db9f15e6..da1b941bd 100644
--- a/seaweed-volume/proto/volume_server.proto
+++ b/seaweed-volume/proto/volume_server.proto
@@ -442,6 +442,7 @@ message VolumeEcShardsCopyRequest {
bool copy_ecj_file = 6;
bool copy_vif_file = 7;
uint32 disk_id = 8; // Target disk ID for storing EC shards
+ bool copy_ecsum_file = 9; // copy the bitrot checksum sidecar (.ecsum) when present; tolerant of a missing source (no-op), since this non-2PC path has no Prepare backstop
}
message VolumeEcShardsCopyResponse {
}
@@ -587,6 +588,29 @@ message EcShardConfig {
uint32 parity_shards = 2; // Number of parity shards (e.g., 4)
int64 encode_ts_ns = 3; // encode time (unix nanos); a read served from a shard of a different encode run is rejected
}
+// EcBitrotProtection is the entire content of a bitrot checksum sidecar
+// (.ecsum for the legacy generation, .ecsum.v for vacuum
+// generation N): per-shard, per-block CRC32C so a CHECKSUM scrub can detect
+// silent bit rot in any shard (including parity) without decoding. Field
+// numbers and types match weed/pb/volume_server.proto byte-for-byte so the
+// serialized sidecar payload is wire-identical across the Go and Rust binaries.
+message EcBitrotProtection {
+ ChecksumAlgorithm algorithm = 1; // CRC32C (Castagnoli)
+ uint32 block_size = 2; // bytes per checksum block; default 16777216 (16 MiB), a power-of-two multiple of 1 MiB
+ uint32 generation = 3; // EC vacuum generation these checksums describe (0 = legacy/fresh); must match the sidecar filename version
+ EcShardConfig ec_shard_config = 4; // data/parity shard counts at encode time
+ repeated EcShardChecksums shards = 5; // one entry per shard id in the active layout
+ bytes encode_uuid = 6; // random per-encode identity, for stale-sidecar detection across in-place re-encodes
+}
+message EcShardChecksums {
+ uint32 shard_id = 1; // 0..MaxShardCount-1 (custom EC ratios go up to 32)
+ int64 covered_size = 2; // shard byte length these checksums cover (must equal the on-disk shard length)
+ bytes block_crc32c = 3; // packed little-endian uint32[] = ceil(covered_size/block_size) entries
+}
+enum ChecksumAlgorithm {
+ CHECKSUM_NONE = 0;
+ CHECKSUM_CRC32C = 1;
+}
message OldVersionVolumeInfo {
repeated RemoteFile files = 1;
uint32 version = 2;
@@ -664,6 +688,7 @@ enum VolumeScrubMode {
INDEX = 1;
FULL = 2;
LOCAL = 3;
+ CHECKSUM = 4; // EC only: verify each local shard's raw bytes against the bitrot checksum sidecar
}
message ScrubVolumeRequest {
diff --git a/seaweed-volume/src/server/grpc_server.rs b/seaweed-volume/src/server/grpc_server.rs
index e1535f7b1..1371a4820 100644
--- a/seaweed-volume/src/server/grpc_server.rs
+++ b/seaweed-volume/src/server/grpc_server.rs
@@ -37,6 +37,7 @@ fn scrub_mode_label(mode: i32) -> &'static str {
1 => "INDEX",
2 => "FULL",
3 => "LOCAL",
+ 4 => "CHECKSUM",
_ => "UNKNOWN",
}
}
@@ -2765,6 +2766,58 @@ impl VolumeServer for VolumeGrpcService {
}
}
+ // Copy the generation-0 bitrot checksum sidecar (.ecsum) when requested, so
+ // protection travels with the shards. Tolerant of a missing source (no-op):
+ // this non-2PC path has no Prepare backstop, and an unprotected source
+ // simply leaves the copy unprotected.
+ if req.copy_ecsum_file {
+ let copy_req = volume_server_pb::CopyFileRequest {
+ volume_id: req.volume_id,
+ collection: req.collection.clone(),
+ is_ec_volume: true,
+ ext: ".ecsum".to_string(),
+ compaction_revision: u32::MAX,
+ stop_offset: i64::MAX as u64,
+ ignore_source_file_not_found: true,
+ ..Default::default()
+ };
+ let mut stream = client
+ .copy_file(copy_req)
+ .await
+ .map_err(|e| {
+ Status::internal(format!(
+ "VolumeEcShardsCopy volume {} copy .ecsum: {}",
+ vid, e
+ ))
+ })?
+ .into_inner();
+
+ let file_path = {
+ let base =
+ crate::storage::volume::volume_file_name(&dest_dir, &req.collection, vid);
+ format!("{}.ecsum", base)
+ };
+ let mut file = std::fs::File::create(&file_path)
+ .map_err(|e| Status::internal(format!("create {}: {}", file_path, e)))?;
+ let mut written: u64 = 0;
+ while let Some(chunk) = stream
+ .message()
+ .await
+ .map_err(|e| Status::internal(format!("recv .ecsum: {}", e)))?
+ {
+ use std::io::Write;
+ file.write_all(&chunk.file_content)
+ .map_err(|e| Status::internal(format!("write {}: {}", file_path, e)))?;
+ written += chunk.file_content.len() as u64;
+ }
+ // A missing source yields an empty stream; drop the 0-byte file so mount
+ // sees no sidecar (protection Off) rather than a truncated/invalid one.
+ if written == 0 {
+ drop(file);
+ let _ = std::fs::remove_file(&file_path);
+ }
+ }
+
Ok(Response::new(
volume_server_pb::VolumeEcShardsCopyResponse {},
))
@@ -3911,7 +3964,7 @@ impl VolumeServer for VolumeGrpcService {
// Validate mode
let mode = req.mode;
match mode {
- 1 | 2 | 3 => {} // INDEX=1, FULL=2, LOCAL=3
+ 1 | 2 | 3 | 4 => {} // INDEX=1, FULL=2, LOCAL=3, CHECKSUM=4
_ => {
return Err(Status::invalid_argument(format!(
"unsupported EC volume scrub mode {}",
@@ -4058,6 +4111,36 @@ impl VolumeServer for VolumeGrpcService {
}
}
}
+ 4 => {
+ // CHECKSUM: verify each local shard's raw bytes against the
+ // bitrot checksum sidecar, exercising cold parity shards.
+ // Read-only. Mirrors Go's v.ChecksumScrub().
+ let (blocks_scanned, broken, errs, collection) = {
+ let store = self.state.store.read().unwrap();
+ let ecv = store.find_ec_volume(vid).ok_or_else(|| {
+ Status::not_found(format!("EC volume id {} not found", vid.0))
+ })?;
+ let collection = ecv.collection.clone();
+ let (blocks, broken, errs) = ecv.checksum_scrub();
+ (blocks, broken, errs, collection)
+ };
+ total_volumes += 1;
+ total_files += blocks_scanned;
+ if !errs.is_empty() || !broken.is_empty() {
+ broken_volume_ids.push(vid.0);
+ for b in broken {
+ broken_shard_infos.push(volume_server_pb::EcShardInfo {
+ volume_id: vid.0,
+ collection: collection.clone(),
+ shard_id: b,
+ ..Default::default()
+ });
+ }
+ for msg in errs {
+ details.push(format!("ecvol {}: {}", vid.0, msg));
+ }
+ }
+ }
_ => unreachable!(), // validated above
}
}
diff --git a/seaweed-volume/src/storage/disk_location.rs b/seaweed-volume/src/storage/disk_location.rs
index 86d7fbadd..a8458fb6b 100644
--- a/seaweed-volume/src/storage/disk_location.rs
+++ b/seaweed-volume/src/storage/disk_location.rs
@@ -401,6 +401,12 @@ impl DiskLocation {
for i in 0..MAX_SHARD_COUNT {
rm_if_present(format!("{}.ec{:02}", base, i))?;
}
+
+ // Remove the bitrot checksum sidecars from both the data and idx dirs.
+ remove_bitrot_sidecars(&base)?;
+ if self.idx_directory != self.directory {
+ remove_bitrot_sidecars(&idx_base)?;
+ }
Ok(())
}
@@ -1089,6 +1095,49 @@ fn rm_if_present(path: String) -> io::Result<()> {
}
}
+/// Remove the bitrot checksum sidecars for a base file name: the legacy
+/// `.ecsum` (generation 0) and any versioned `.ecsum.v`.
+/// Already-gone is success; returns the first real removal failure (and surfaces
+/// a directory-scan error) so a stale sidecar left behind is not reported as
+/// cleaned. Mirrors Go's removeBitrotSidecars.
+fn remove_bitrot_sidecars(base: &str) -> io::Result<()> {
+ use crate::storage::erasure_coding::ec_bitrot::BITROT_SIDECAR_EXT;
+ let rm = |path: std::path::PathBuf| -> io::Result<()> {
+ match fs::remove_file(&path) {
+ Err(e) if e.kind() != io::ErrorKind::NotFound => Err(e),
+ _ => Ok(()),
+ }
+ };
+ let mut first_err: Option = None;
+ let mut record = |res: io::Result<()>| {
+ if let Err(e) = res {
+ if first_err.is_none() {
+ first_err = Some(e);
+ }
+ }
+ };
+ record(rm(format!("{}{}", base, BITROT_SIDECAR_EXT).into()));
+ let path = std::path::Path::new(base);
+ if let (Some(parent), Some(fname)) = (path.parent(), path.file_name()) {
+ let prefix = format!("{}{}.v", fname.to_string_lossy(), BITROT_SIDECAR_EXT);
+ match fs::read_dir(parent) {
+ Ok(entries) => {
+ for entry in entries.flatten() {
+ if entry.file_name().to_string_lossy().starts_with(&prefix) {
+ record(rm(entry.path()));
+ }
+ }
+ }
+ Err(e) if e.kind() != io::ErrorKind::NotFound => record(Err(e)),
+ Err(_) => {}
+ }
+ }
+ match first_err {
+ Some(e) => Err(e),
+ None => Ok(()),
+ }
+}
+
fn ec_data_shards_from_vif(directory: &str, idx_directory: &str, collection: &str, vid: VolumeId) -> usize {
for dir in [directory, idx_directory] {
let vif = format!("{}.vif", volume_file_name(dir, collection, vid));
diff --git a/seaweed-volume/src/storage/erasure_coding/ec_bitrot.rs b/seaweed-volume/src/storage/erasure_coding/ec_bitrot.rs
new file mode 100644
index 000000000..06a31167f
--- /dev/null
+++ b/seaweed-volume/src/storage/erasure_coding/ec_bitrot.rs
@@ -0,0 +1,827 @@
+//! EC bitrot detection — checksum sidecar.
+//!
+//! A per-volume sidecar file stores a CRC32C (Castagnoli) checksum for every
+//! fixed-size block of every EC shard, so a scrub (and the reconstruction path)
+//! can detect silent disk corruption in any shard — including cold parity shards
+//! that are never read during normal serving.
+//!
+//! The sidecar is OPTIONAL: an absent or generation-mismatched sidecar simply
+//! means "feature off" for that generation, so old binaries, JSON-only nodes,
+//! and rollback deployments ignore it and degrade gracefully.
+//!
+//! On-disk layout of `.ecsum` (legacy/generation 0) and `.ecsum.v`:
+//!
+//! ```text
+//! [ magic(4) | format_version(2) | payload_len(4) | payload_crc32c(4) ] [ proto payload ]
+//! ```
+//!
+//! All header fields are BIG-ENDIAN. The header's `payload_crc32c` lets a loader
+//! detect corruption of the sidecar itself BEFORE trusting any contents, so a
+//! rotted sidecar can never be mistaken for shard corruption. This format is
+//! byte-identical to the Go implementation in
+//! `weed/storage/erasure_coding/ec_bitrot.go`.
+
+use std::fs::File;
+use std::io::{self, Read, Write};
+
+use prost::Message;
+
+use crate::pb::volume_server_pb::{
+ ChecksumAlgorithm, EcBitrotProtection, EcShardChecksums, EcShardConfig,
+};
+use crate::storage::erasure_coding::ec_shard::MAX_SHARD_COUNT;
+use crate::storage::needle::crc::CRC;
+
+/// Canonical extension for the checksum sidecar. Generation 0 (legacy/fresh
+/// encode) uses `.ecsum`; vacuum generation N uses `.ecsum.v`,
+/// mirroring the `.vif`/`.ecx` versioned convention.
+pub const BITROT_SIDECAR_EXT: &str = ".ecsum";
+
+/// Default checksum granularity (16 MiB). It is a power-of-two multiple of
+/// `ERASURE_CODING_SMALL_BLOCK_SIZE` (1 MiB) and keeps the sidecar tiny
+/// (~11 KB for a 30 GB volume) while localizing corruption to a 16 MiB region.
+pub const DEFAULT_BITROT_BLOCK_SIZE: usize = 16 * 1024 * 1024;
+
+/// Caps the block granularity so a loaded sidecar cannot force a huge
+/// scrub/verify scratch buffer. Power-of-two multiple of 1 MiB.
+pub const MAX_BITROT_BLOCK_SIZE: u32 = 64 * 1024 * 1024;
+
+/// Magic "ECSU".
+pub const BITROT_MAGIC: u32 = 0x4543_5355;
+/// On-disk format version.
+pub const BITROT_FORMAT_VERSION: u16 = 1;
+/// Header size: magic(4) + version(2) + payload_len(4) + payload_crc32c(4).
+pub const BITROT_HEADER_SIZE: usize = 14;
+
+/// Resolved protection state of an EC volume's active generation after loading
+/// and validating its sidecar.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum BitrotStatus {
+ /// No sidecar, or a sidecar that does not describe the active generation.
+ /// The generation is unprotected; this is NOT corruption.
+ Off,
+ /// A complete, well-formed, generation-matching sidecar is loaded.
+ On,
+ /// A generation-matching sidecar that is malformed, incomplete, or
+ /// self-integrity-failed. The generation is unprotected pending repair of
+ /// the sidecar, and an integrity alarm should fire. The rebuild path treats
+ /// this as fail-closed.
+ Invalid,
+}
+
+impl std::fmt::Display for BitrotStatus {
+ fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+ let s = match self {
+ BitrotStatus::On => "on",
+ BitrotStatus::Invalid => "invalid",
+ BitrotStatus::Off => "off",
+ };
+ f.write_str(s)
+ }
+}
+
+/// Error returned by [`load_bitrot_sidecar`]. A self-integrity failure is a
+/// sidecar-integrity problem (the caller maps it to [`BitrotStatus::Invalid`]),
+/// never a shard-corruption signal.
+#[derive(Debug)]
+pub enum BitrotLoadError {
+ /// File missing or other underlying I/O error.
+ Io(io::Error),
+ /// File shorter than the fixed header.
+ TooShort(usize),
+ /// Header magic did not match.
+ BadMagic(u32),
+ /// Header format version is unsupported.
+ UnsupportedVersion(u16),
+ /// Header payload_len disagrees with the actual payload length.
+ LengthMismatch { header: u32, actual: usize },
+ /// Header payload_crc32c disagrees with the computed CRC32C of the payload.
+ CrcMismatch { header: u32, computed: u32 },
+ /// Protobuf payload failed to decode.
+ Decode(prost::DecodeError),
+}
+
+impl std::fmt::Display for BitrotLoadError {
+ fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+ match self {
+ BitrotLoadError::Io(e) => write!(f, "bitrot sidecar io error: {}", e),
+ BitrotLoadError::TooShort(n) => {
+ write!(f, "bitrot sidecar too short ({} bytes)", n)
+ }
+ BitrotLoadError::BadMagic(m) => write!(f, "bitrot sidecar bad magic {:#x}", m),
+ BitrotLoadError::UnsupportedVersion(v) => {
+ write!(f, "bitrot sidecar unsupported format version {}", v)
+ }
+ BitrotLoadError::LengthMismatch { header, actual } => write!(
+ f,
+ "bitrot sidecar length mismatch: header {}, actual {}",
+ header, actual
+ ),
+ BitrotLoadError::CrcMismatch { header, computed } => write!(
+ f,
+ "bitrot sidecar self-integrity CRC mismatch: header {:#x}, computed {:#x}",
+ header, computed
+ ),
+ BitrotLoadError::Decode(e) => write!(f, "unmarshal bitrot sidecar: {}", e),
+ }
+ }
+}
+
+impl std::error::Error for BitrotLoadError {}
+
+impl From for BitrotLoadError {
+ fn from(e: io::Error) -> Self {
+ BitrotLoadError::Io(e)
+ }
+}
+
+/// Returns the sidecar path for a base file name and EC generation. Generation
+/// 0 is the un-suffixed legacy path; generation N>0 is the versioned path,
+/// consistent with how `.vif`/`.ecx` are versioned by the 2PC switch.
+pub fn bitrot_sidecar_path(base: &str, generation: u32) -> String {
+ if generation == 0 {
+ format!("{}{}", base, BITROT_SIDECAR_EXT)
+ } else {
+ format!("{}{}.v{}", base, BITROT_SIDECAR_EXT, generation)
+ }
+}
+
+/// Returns a fresh random per-encode identity used to detect a stale sidecar
+/// left behind by an in-place re-encode.
+pub fn new_encode_uuid() -> Vec {
+ use rand::RngCore;
+ let mut b = vec![0u8; 16];
+ rand::thread_rng().fill_bytes(&mut b);
+ b
+}
+
+/// Reports whether `block_size` is a power of two in [1 MiB, MAX_BITROT_BLOCK_SIZE].
+pub fn is_pow2_multiple_of_1mib(block_size: u32) -> bool {
+ block_size >= (1 << 20) && block_size <= MAX_BITROT_BLOCK_SIZE && block_size.count_ones() == 1
+}
+
+/// Returns ceil(covered_size / block_size).
+fn expected_block_count(covered_size: i64, block_size: i64) -> usize {
+ if block_size <= 0 {
+ return 0;
+ }
+ ((covered_size + block_size - 1) / block_size) as usize
+}
+
+/// Packs a slice of u32 into little-endian bytes.
+fn pack_u32_le(vals: &[u32]) -> Vec {
+ let mut out = Vec::with_capacity(vals.len() * 4);
+ for v in vals {
+ out.extend_from_slice(&v.to_le_bytes());
+ }
+ out
+}
+
+/// Unpacks little-endian bytes into a Vec. Trailing bytes (len % 4) are
+/// ignored, matching the Go implementation's `len(b)/4` truncation.
+fn unpack_u32_le(b: &[u8]) -> Vec {
+ let n = b.len() / 4;
+ let mut out = Vec::with_capacity(n);
+ for i in 0..n {
+ out.push(u32::from_le_bytes([
+ b[i * 4],
+ b[i * 4 + 1],
+ b[i * 4 + 2],
+ b[i * 4 + 3],
+ ]));
+ }
+ out
+}
+
+/// Accumulates the per-block CRC32C of a single shard's byte stream as it is
+/// written. Tolerates arbitrary chunk sizes that cross block boundaries, so it
+/// works for both small encode buffers and the larger rebuild buffers.
+pub struct ShardChecksumBuilder {
+ block_size: i64,
+ cur: CRC,
+ cur_len: i64,
+ total: i64,
+ blocks: Vec,
+}
+
+impl ShardChecksumBuilder {
+ /// Creates a builder over a given block size in bytes.
+ pub fn new(block_size: i64) -> Self {
+ ShardChecksumBuilder {
+ block_size,
+ cur: CRC(0),
+ cur_len: 0,
+ total: 0,
+ blocks: Vec::new(),
+ }
+ }
+
+ /// Feeds a chunk of arbitrary size, splitting it across block boundaries.
+ pub fn write(&mut self, mut p: &[u8]) {
+ while !p.is_empty() {
+ let room = self.block_size - self.cur_len;
+ let n = (p.len() as i64).min(room) as usize;
+ self.cur = self.cur.update(&p[..n]);
+ self.cur_len += n as i64;
+ self.total += n as i64;
+ p = &p[n..];
+ if self.cur_len == self.block_size {
+ self.blocks.push(self.cur.0);
+ self.cur = CRC(0);
+ self.cur_len = 0;
+ }
+ }
+ }
+
+ /// Flushes any partial last block and returns the covered size and the
+ /// packed little-endian u32 CRC array.
+ pub fn finalize(mut self) -> (i64, Vec) {
+ if self.cur_len > 0 {
+ self.blocks.push(self.cur.0);
+ self.cur = CRC(0);
+ self.cur_len = 0;
+ }
+ (self.total, pack_u32_le(&self.blocks))
+ }
+}
+
+/// Atomically writes `prot` to `path`, wrapped in the on-disk header with a
+/// CRC32C over the serialized payload (temp file + rename).
+pub fn save_bitrot_sidecar(path: &str, prot: &EcBitrotProtection) -> io::Result<()> {
+ let payload = prot.encode_to_vec();
+ let mut buf = Vec::with_capacity(BITROT_HEADER_SIZE + payload.len());
+ buf.extend_from_slice(&BITROT_MAGIC.to_be_bytes());
+ buf.extend_from_slice(&BITROT_FORMAT_VERSION.to_be_bytes());
+ buf.extend_from_slice(&(payload.len() as u32).to_be_bytes());
+ buf.extend_from_slice(&CRC::new(&payload).0.to_be_bytes());
+ buf.extend_from_slice(&payload);
+
+ let tmp = format!("{}.tmp", path);
+ {
+ let mut f = File::create(&tmp)?;
+ f.write_all(&buf)?;
+ f.sync_all()?;
+ }
+ if let Err(e) = std::fs::rename(&tmp, path) {
+ let _ = std::fs::remove_file(&tmp);
+ return Err(e);
+ }
+ Ok(())
+}
+
+/// Reads and self-integrity-checks a sidecar file. Returns the parsed message,
+/// or an error if the file is missing, truncated, has a bad magic/version, or
+/// fails the payload CRC. A self-integrity failure is a sidecar-integrity
+/// problem (caller maps it to [`BitrotStatus::Invalid`]), never a shard
+/// corruption signal.
+pub fn load_bitrot_sidecar(path: &str) -> Result {
+ let mut data = Vec::new();
+ File::open(path)?.read_to_end(&mut data)?;
+ if data.len() < BITROT_HEADER_SIZE {
+ return Err(BitrotLoadError::TooShort(data.len()));
+ }
+ let magic = u32::from_be_bytes([data[0], data[1], data[2], data[3]]);
+ if magic != BITROT_MAGIC {
+ return Err(BitrotLoadError::BadMagic(magic));
+ }
+ let ver = u16::from_be_bytes([data[4], data[5]]);
+ if ver != BITROT_FORMAT_VERSION {
+ return Err(BitrotLoadError::UnsupportedVersion(ver));
+ }
+ let payload_len = u32::from_be_bytes([data[6], data[7], data[8], data[9]]);
+ let want_crc = u32::from_be_bytes([data[10], data[11], data[12], data[13]]);
+ let payload = &data[BITROT_HEADER_SIZE..];
+ if payload_len as usize != payload.len() {
+ return Err(BitrotLoadError::LengthMismatch {
+ header: payload_len,
+ actual: payload.len(),
+ });
+ }
+ let got = CRC::new(payload).0;
+ if got != want_crc {
+ return Err(BitrotLoadError::CrcMismatch {
+ header: want_crc,
+ computed: got,
+ });
+ }
+ EcBitrotProtection::decode(payload).map_err(BitrotLoadError::Decode)
+}
+
+/// Performs the disk-free manifest/syntax checks that every loader runs:
+/// supported algorithm, valid block size, exactly one entry per shard id in the
+/// active layout (no duplicates, no out-of-range ids), positive covered_size,
+/// and a packed-CRC count consistent with covered_size.
+///
+/// It does NOT compare covered_size against on-disk shard lengths — that is a
+/// per-node physical check done only for locally-held shards.
+pub fn validate_manifest(
+ prot: &EcBitrotProtection,
+ data_shards: usize,
+ parity_shards: usize,
+) -> Result<(), String> {
+ if prot.algorithm != ChecksumAlgorithm::ChecksumCrc32c as i32 {
+ return Err(format!("unsupported checksum algorithm {}", prot.algorithm));
+ }
+ if !is_pow2_multiple_of_1mib(prot.block_size) {
+ return Err(format!(
+ "invalid block_size {} (must be a power-of-two multiple of 1 MiB, at most {})",
+ prot.block_size, MAX_BITROT_BLOCK_SIZE
+ ));
+ }
+ let bs = prot.block_size as i64;
+ let total = data_shards + parity_shards;
+ if total == 0 || total > MAX_SHARD_COUNT {
+ return Err(format!(
+ "invalid active layout: data={} parity={}",
+ data_shards, parity_shards
+ ));
+ }
+ if prot.shards.len() != total {
+ return Err(format!(
+ "incomplete manifest: {} shard entries, expected {}",
+ prot.shards.len(),
+ total
+ ));
+ }
+ let mut seen = vec![false; MAX_SHARD_COUNT];
+ for s in &prot.shards {
+ if s.shard_id >= total as u32 {
+ return Err(format!(
+ "shard id {} out of range [0,{})",
+ s.shard_id, total
+ ));
+ }
+ if seen[s.shard_id as usize] {
+ return Err(format!("duplicate shard id {}", s.shard_id));
+ }
+ seen[s.shard_id as usize] = true;
+ if s.covered_size <= 0 {
+ return Err(format!(
+ "shard {} has non-positive covered_size {}",
+ s.shard_id, s.covered_size
+ ));
+ }
+ let want_count = expected_block_count(s.covered_size, bs);
+ if s.block_crc32c.len() != want_count * 4 {
+ return Err(format!(
+ "shard {} crc count mismatch: {} bytes, expected {} (covered_size={} block_size={})",
+ s.shard_id,
+ s.block_crc32c.len(),
+ want_count * 4,
+ s.covered_size,
+ prot.block_size
+ ));
+ }
+ }
+ Ok(())
+}
+
+/// Resolves the protection status of a loaded-or-missing sidecar against the
+/// active generation and layout. `loaded` is the result of attempting to load
+/// the sidecar at the active generation's path.
+///
+/// - missing sidecar (NotFound) => [`BitrotStatus::Off`]
+/// - load/self-integrity failure => [`BitrotStatus::Invalid`]
+/// - generation mismatch => [`BitrotStatus::Off`]
+/// - manifest validation failure => [`BitrotStatus::Invalid`]
+/// - otherwise => [`BitrotStatus::On`]
+pub fn resolve_status(
+ loaded: &Result,
+ active_generation: u32,
+ data_shards: usize,
+ parity_shards: usize,
+) -> BitrotStatus {
+ match loaded {
+ Err(BitrotLoadError::Io(e)) if e.kind() == io::ErrorKind::NotFound => BitrotStatus::Off,
+ Err(_) => BitrotStatus::Invalid,
+ Ok(prot) => {
+ if prot.generation != active_generation {
+ return BitrotStatus::Off;
+ }
+ if validate_manifest(prot, data_shards, parity_shards).is_err() {
+ return BitrotStatus::Invalid;
+ }
+ BitrotStatus::On
+ }
+ }
+}
+
+/// Returns the [`EcShardChecksums`] entry for a shard id, or `None`.
+pub fn shard_checksums(prot: &EcBitrotProtection, shard_id: u32) -> Option<&EcShardChecksums> {
+ prot.shards.iter().find(|s| s.shard_id == shard_id)
+}
+
+/// Reads a shard file at `path` in `block_size` chunks and compares each block's
+/// CRC32C against the manifest entry. Returns the list of mismatching block
+/// indices (empty == clean), or a fatal `io::Error` for genuine I/O problems.
+///
+/// A length mismatch (truncation or unexpected trailing bytes) is itself shard
+/// corruption: every block index is reported as mismatched so the caller treats
+/// the shard as bad. It does not interpret the result — the caller (scrub /
+/// rebuild) arbitrates shard-vs-sidecar via Reed-Solomon before acting.
+pub fn verify_shard_file_blocks(
+ path: &str,
+ entry: &EcShardChecksums,
+ block_size: i64,
+) -> io::Result> {
+ let f = File::open(path)?;
+ let file_size = f.metadata()?.len() as i64;
+ let want = unpack_u32_le(&entry.block_crc32c);
+
+ if file_size != entry.covered_size {
+ // Length drift is shard corruption: report every block as mismatched.
+ return Ok((0..want.len()).collect());
+ }
+
+ let mut mismatched = Vec::new();
+ let mut buf = vec![0u8; block_size.max(1) as usize];
+ let mut offset: i64 = 0;
+ for (i, want_crc) in want.iter().enumerate() {
+ let to_read = (entry.covered_size - offset).min(block_size);
+ if to_read <= 0 {
+ break;
+ }
+ let to_read = to_read as usize;
+ read_full_at(&f, &mut buf[..to_read], offset as u64)?;
+ if CRC::new(&buf[..to_read]).0 != *want_crc {
+ mismatched.push(i);
+ }
+ offset += to_read as i64;
+ }
+ Ok(mismatched)
+}
+
+/// Reads exactly `buf.len()` bytes from `f` at `offset`, erroring on early EOF.
+fn read_full_at(f: &File, buf: &mut [u8], offset: u64) -> io::Result<()> {
+ let mut total = 0usize;
+ while total < buf.len() {
+ #[cfg(unix)]
+ let n = {
+ use std::os::unix::fs::FileExt;
+ f.read_at(&mut buf[total..], offset + total as u64)?
+ };
+ #[cfg(not(unix))]
+ let n = {
+ use std::io::{Read, Seek, SeekFrom};
+ let mut fc = f.try_clone()?;
+ fc.seek(SeekFrom::Start(offset + total as u64))?;
+ fc.read(&mut buf[total..])?
+ };
+ if n == 0 {
+ return Err(io::Error::new(
+ io::ErrorKind::UnexpectedEof,
+ "short read on shard block",
+ ));
+ }
+ total += n;
+ }
+ Ok(())
+}
+
+/// Builds the `EcShardConfig` proto for the given layout. The bitrot sidecar
+/// carries its own top-level encode_uuid, so the nested config leaves it empty.
+pub fn ec_shard_config(data_shards: u32, parity_shards: u32) -> EcShardConfig {
+ EcShardConfig {
+ data_shards,
+ parity_shards,
+ encode_ts_ns: 0,
+ }
+}
+
+#[cfg(test)]
+mod tests {
+ use super::*;
+
+ /// Cross-binary byte-exact proof: CANONICAL_HEX equals `canonicalInteropHex`
+ /// in weed/storage/erasure_coding/ec_bitrot_interop_test.go (the Go reference
+ /// asserts the same constant). Both binaries port the same format, so a
+ /// sidecar written by either must be byte-identical; this pins the Rust side
+ /// of that guarantee. If you change the format, regenerate and update BOTH.
+ #[test]
+ fn test_byte_exact_go_interop() {
+ const CANONICAL_HEX: &str = "45435355000100000039cc1b826a080110808080082204080a10042a0a108080401a04040302012a0c0801108080401a04080706053210000102030405060708090a0b0c0d0e0f";
+ let prot = EcBitrotProtection {
+ algorithm: ChecksumAlgorithm::ChecksumCrc32c as i32,
+ block_size: DEFAULT_BITROT_BLOCK_SIZE as u32,
+ generation: 0,
+ ec_shard_config: Some(EcShardConfig {
+ data_shards: 10,
+ parity_shards: 4,
+ encode_ts_ns: 0,
+ }),
+ shards: vec![
+ EcShardChecksums {
+ shard_id: 0,
+ covered_size: 1024 * 1024,
+ block_crc32c: pack_u32_le(&[0x0102_0304]),
+ },
+ EcShardChecksums {
+ shard_id: 1,
+ covered_size: 1024 * 1024,
+ block_crc32c: pack_u32_le(&[0x0506_0708]),
+ },
+ ],
+ encode_uuid: (0..16u8).collect(),
+ };
+ let dir = std::env::temp_dir().join(format!("ecsum_interop_{}", std::process::id()));
+ std::fs::create_dir_all(&dir).unwrap();
+ let path = dir.join("v1.ecsum");
+ let path = path.to_str().unwrap();
+ save_bitrot_sidecar(path, &prot).unwrap();
+ let bytes = std::fs::read(path).unwrap();
+ let hex: String = bytes.iter().map(|b| format!("{:02x}", b)).collect();
+ assert_eq!(hex, CANONICAL_HEX, "Rust .ecsum bytes drifted from the Go canonical form");
+ let _ = std::fs::remove_file(path);
+ }
+
+ #[test]
+ fn test_sidecar_path_generations() {
+ assert_eq!(bitrot_sidecar_path("/d/1", 0), "/d/1.ecsum");
+ assert_eq!(bitrot_sidecar_path("/d/1", 3), "/d/1.ecsum.v3");
+ }
+
+ #[test]
+ fn test_is_pow2_multiple_of_1mib() {
+ assert!(is_pow2_multiple_of_1mib(1 << 20)); // 1 MiB
+ assert!(is_pow2_multiple_of_1mib(16 * 1024 * 1024)); // 16 MiB default
+ assert!(is_pow2_multiple_of_1mib(1 << 25));
+ assert!(is_pow2_multiple_of_1mib(MAX_BITROT_BLOCK_SIZE)); // 64 MiB boundary
+ assert!(!is_pow2_multiple_of_1mib(0));
+ assert!(!is_pow2_multiple_of_1mib(1 << 19)); // 512 KiB, too small
+ assert!(!is_pow2_multiple_of_1mib(3 << 20)); // 3 MiB, not pow2
+ assert!(!is_pow2_multiple_of_1mib(128 * 1024 * 1024)); // pow2 but > MAX_BITROT_BLOCK_SIZE
+ assert!(!is_pow2_multiple_of_1mib(DEFAULT_BITROT_BLOCK_SIZE as u32 + 1));
+ }
+
+ #[test]
+ fn test_expected_block_count() {
+ assert_eq!(expected_block_count(0, 16), 0);
+ assert_eq!(expected_block_count(1, 16), 1);
+ assert_eq!(expected_block_count(16, 16), 1);
+ assert_eq!(expected_block_count(17, 16), 2);
+ assert_eq!(expected_block_count(32, 16), 2);
+ assert_eq!(expected_block_count(100, 0), 0);
+ }
+
+ #[test]
+ fn test_pack_unpack_roundtrip() {
+ let vals = vec![0x0102_0304u32, 0xdead_beef, 0, u32::MAX];
+ let packed = pack_u32_le(&vals);
+ assert_eq!(packed.len(), 16);
+ // Verify little-endian byte order of the first entry.
+ assert_eq!(&packed[0..4], &[0x04, 0x03, 0x02, 0x01]);
+ assert_eq!(unpack_u32_le(&packed), vals);
+ }
+
+ #[test]
+ fn test_builder_block_boundaries() {
+ // block_size = 4; feed 10 bytes in chunks that cross boundaries.
+ let mut b = ShardChecksumBuilder::new(4);
+ let data = b"0123456789";
+ b.write(&data[0..3]); // partial block 0
+ b.write(&data[3..7]); // completes block 0 (idx 3), fills block 1
+ b.write(&data[7..10]); // partial block 2
+ let (covered, packed) = b.finalize();
+ assert_eq!(covered, 10);
+ let crcs = unpack_u32_le(&packed);
+ // ceil(10/4) = 3 blocks
+ assert_eq!(crcs.len(), 3);
+ // Compare against direct per-block CRCs.
+ assert_eq!(crcs[0], CRC::new(&data[0..4]).0);
+ assert_eq!(crcs[1], CRC::new(&data[4..8]).0);
+ assert_eq!(crcs[2], CRC::new(&data[8..10]).0);
+ }
+
+ #[test]
+ fn test_builder_exact_block_multiple() {
+ let mut b = ShardChecksumBuilder::new(4);
+ b.write(b"01234567"); // exactly 2 blocks, no partial
+ let (covered, packed) = b.finalize();
+ assert_eq!(covered, 8);
+ assert_eq!(unpack_u32_le(&packed).len(), 2);
+ }
+
+ #[test]
+ fn test_save_load_roundtrip() {
+ let tmp = tempfile::TempDir::new().unwrap();
+ let path = tmp
+ .path()
+ .join("vol.ecsum")
+ .to_str()
+ .unwrap()
+ .to_string();
+
+ let mut builder = ShardChecksumBuilder::new(DEFAULT_BITROT_BLOCK_SIZE as i64);
+ builder.write(b"hello world");
+ let (covered, packed) = builder.finalize();
+
+ let prot = EcBitrotProtection {
+ algorithm: ChecksumAlgorithm::ChecksumCrc32c as i32,
+ block_size: DEFAULT_BITROT_BLOCK_SIZE as u32,
+ generation: 0,
+ ec_shard_config: Some(ec_shard_config(10, 4)),
+ shards: vec![EcShardChecksums {
+ shard_id: 0,
+ covered_size: covered,
+ block_crc32c: packed,
+ }],
+ encode_uuid: new_encode_uuid(),
+ };
+
+ save_bitrot_sidecar(&path, &prot).unwrap();
+ let loaded = load_bitrot_sidecar(&path).unwrap();
+ assert_eq!(loaded, prot);
+ }
+
+ #[test]
+ fn test_load_rejects_bad_magic() {
+ let tmp = tempfile::TempDir::new().unwrap();
+ let path = tmp.path().join("bad.ecsum").to_str().unwrap().to_string();
+ std::fs::write(&path, vec![0u8; BITROT_HEADER_SIZE + 4]).unwrap();
+ match load_bitrot_sidecar(&path) {
+ Err(BitrotLoadError::BadMagic(_)) => {}
+ other => panic!("expected BadMagic, got {:?}", other),
+ }
+ }
+
+ #[test]
+ fn test_load_rejects_corrupted_payload() {
+ let tmp = tempfile::TempDir::new().unwrap();
+ let path = tmp
+ .path()
+ .join("corrupt.ecsum")
+ .to_str()
+ .unwrap()
+ .to_string();
+ let prot = EcBitrotProtection {
+ algorithm: ChecksumAlgorithm::ChecksumCrc32c as i32,
+ block_size: DEFAULT_BITROT_BLOCK_SIZE as u32,
+ generation: 0,
+ ec_shard_config: Some(ec_shard_config(10, 4)),
+ shards: vec![EcShardChecksums {
+ shard_id: 0,
+ covered_size: 5,
+ block_crc32c: pack_u32_le(&[CRC::new(b"hello").0]),
+ }],
+ encode_uuid: vec![0u8; 16],
+ };
+ save_bitrot_sidecar(&path, &prot).unwrap();
+
+ // Flip a byte in the payload (after the 14-byte header).
+ let mut data = std::fs::read(&path).unwrap();
+ let last = data.len() - 1;
+ data[last] ^= 0xff;
+ std::fs::write(&path, &data).unwrap();
+
+ match load_bitrot_sidecar(&path) {
+ Err(BitrotLoadError::CrcMismatch { .. }) => {}
+ other => panic!("expected CrcMismatch, got {:?}", other),
+ }
+ }
+
+ #[test]
+ fn test_load_missing_is_notfound() {
+ let res = load_bitrot_sidecar("/nonexistent/path/x.ecsum");
+ match res {
+ Err(BitrotLoadError::Io(e)) => assert_eq!(e.kind(), io::ErrorKind::NotFound),
+ other => panic!("expected Io(NotFound), got {:?}", other),
+ }
+ }
+
+ fn good_manifest() -> EcBitrotProtection {
+ let mut shards = Vec::new();
+ for id in 0..14u32 {
+ shards.push(EcShardChecksums {
+ shard_id: id,
+ covered_size: 5,
+ block_crc32c: pack_u32_le(&[CRC::new(b"hello").0]),
+ });
+ }
+ EcBitrotProtection {
+ algorithm: ChecksumAlgorithm::ChecksumCrc32c as i32,
+ block_size: DEFAULT_BITROT_BLOCK_SIZE as u32,
+ generation: 0,
+ ec_shard_config: Some(ec_shard_config(10, 4)),
+ shards,
+ encode_uuid: vec![0u8; 16],
+ }
+ }
+
+ #[test]
+ fn test_validate_manifest_ok() {
+ assert!(validate_manifest(&good_manifest(), 10, 4).is_ok());
+ }
+
+ #[test]
+ fn test_validate_rejects_wrong_algorithm() {
+ let mut m = good_manifest();
+ m.algorithm = ChecksumAlgorithm::ChecksumNone as i32;
+ assert!(validate_manifest(&m, 10, 4).is_err());
+ }
+
+ #[test]
+ fn test_validate_rejects_bad_block_size() {
+ let mut m = good_manifest();
+ m.block_size = 3 << 20;
+ assert!(validate_manifest(&m, 10, 4).is_err());
+ }
+
+ #[test]
+ fn test_validate_rejects_incomplete() {
+ let mut m = good_manifest();
+ m.shards.pop();
+ assert!(validate_manifest(&m, 10, 4).is_err());
+ }
+
+ #[test]
+ fn test_validate_rejects_duplicate_shard_id() {
+ let mut m = good_manifest();
+ m.shards[1].shard_id = 0;
+ assert!(validate_manifest(&m, 10, 4).is_err());
+ }
+
+ #[test]
+ fn test_validate_rejects_out_of_range_id() {
+ let mut m = good_manifest();
+ m.shards[13].shard_id = 14;
+ assert!(validate_manifest(&m, 10, 4).is_err());
+ }
+
+ #[test]
+ fn test_validate_rejects_nonpositive_covered_size() {
+ let mut m = good_manifest();
+ m.shards[0].covered_size = 0;
+ assert!(validate_manifest(&m, 10, 4).is_err());
+ }
+
+ #[test]
+ fn test_validate_rejects_crc_count_mismatch() {
+ let mut m = good_manifest();
+ m.shards[0].block_crc32c = vec![0u8; 8]; // 2 entries but covered_size=5 => want 1
+ assert!(validate_manifest(&m, 10, 4).is_err());
+ }
+
+ #[test]
+ fn test_resolve_status() {
+ // Missing => Off.
+ let notfound: Result = Err(BitrotLoadError::Io(
+ io::Error::new(io::ErrorKind::NotFound, "x"),
+ ));
+ assert_eq!(resolve_status(¬found, 0, 10, 4), BitrotStatus::Off);
+
+ // Integrity failure => Invalid.
+ let bad: Result =
+ Err(BitrotLoadError::BadMagic(0));
+ assert_eq!(resolve_status(&bad, 0, 10, 4), BitrotStatus::Invalid);
+
+ // Generation mismatch => Off.
+ let mut m = good_manifest();
+ m.generation = 7;
+ let ok: Result = Ok(m);
+ assert_eq!(resolve_status(&ok, 0, 10, 4), BitrotStatus::Off);
+
+ // Matching + valid => On.
+ let ok2: Result = Ok(good_manifest());
+ assert_eq!(resolve_status(&ok2, 0, 10, 4), BitrotStatus::On);
+
+ // Matching generation but invalid manifest => Invalid.
+ let mut bad_m = good_manifest();
+ bad_m.shards.pop();
+ let ok3: Result = Ok(bad_m);
+ assert_eq!(resolve_status(&ok3, 0, 10, 4), BitrotStatus::Invalid);
+ }
+
+ #[test]
+ fn test_verify_shard_file_blocks() {
+ let tmp = tempfile::TempDir::new().unwrap();
+ let path = tmp.path().join("s.ec00").to_str().unwrap().to_string();
+ let block_size: i64 = 4;
+ let data = b"0123456789"; // 10 bytes, 3 blocks
+ std::fs::write(&path, data).unwrap();
+
+ let mut b = ShardChecksumBuilder::new(block_size);
+ b.write(data);
+ let (covered, packed) = b.finalize();
+ let entry = EcShardChecksums {
+ shard_id: 0,
+ covered_size: covered,
+ block_crc32c: packed,
+ };
+
+ // Clean file => no mismatches.
+ let mm = verify_shard_file_blocks(&path, &entry, block_size).unwrap();
+ assert!(mm.is_empty());
+
+ // Corrupt block index 1 (bytes 4..8).
+ let mut corrupt = data.to_vec();
+ corrupt[5] ^= 0xff;
+ std::fs::write(&path, &corrupt).unwrap();
+ let mm = verify_shard_file_blocks(&path, &entry, block_size).unwrap();
+ assert_eq!(mm, vec![1]);
+
+ // Truncation => all blocks mismatched.
+ std::fs::write(&path, b"012").unwrap();
+ let mm = verify_shard_file_blocks(&path, &entry, block_size).unwrap();
+ assert_eq!(mm, vec![0, 1, 2]);
+ }
+}
diff --git a/seaweed-volume/src/storage/erasure_coding/ec_encoder.rs b/seaweed-volume/src/storage/erasure_coding/ec_encoder.rs
index ad01f2012..c66e63c07 100644
--- a/seaweed-volume/src/storage/erasure_coding/ec_encoder.rs
+++ b/seaweed-volume/src/storage/erasure_coding/ec_encoder.rs
@@ -10,6 +10,12 @@ use std::io::{Read, Seek, SeekFrom};
use reed_solomon_erasure::galois_8::ReedSolomon;
+use crate::pb::volume_server_pb::{
+ ChecksumAlgorithm, EcBitrotProtection, EcShardChecksums,
+};
+use crate::storage::erasure_coding::ec_bitrot::{
+ self, ShardChecksumBuilder, DEFAULT_BITROT_BLOCK_SIZE,
+};
use crate::storage::erasure_coding::ec_shard::*;
use crate::storage::idx;
use crate::storage::types::*;
@@ -52,12 +58,21 @@ pub fn write_ec_files(
shard.create()?;
}
+ // Per-shard bitrot checksum builders: accumulate a CRC32C for every
+ // DEFAULT_BITROT_BLOCK_SIZE block of each shard's byte stream as it is
+ // written, so the resulting `.ecsum` sidecar can later detect silent
+ // corruption in any shard (including cold parity).
+ let mut builders: Vec = (0..total_shards)
+ .map(|_| ShardChecksumBuilder::new(DEFAULT_BITROT_BLOCK_SIZE as i64))
+ .collect();
+
// Encode in large blocks, then small blocks
encode_dat_file(
&dat_file,
dat_size,
&rs,
&mut shards,
+ &mut builders,
data_shards,
parity_shards,
)?;
@@ -67,6 +82,42 @@ pub fn write_ec_files(
shard.close();
}
+ // Write the generation-0 bitrot sidecar (`.ecsum`). Finalizing each
+ // builder yields covered_size (== total bytes written to that shard) and
+ // the packed little-endian CRC32C array.
+ let mut shard_checksums: Vec = Vec::with_capacity(total_shards);
+ for (i, builder) in builders.into_iter().enumerate() {
+ let (covered_size, packed) = builder.finalize();
+ shard_checksums.push(EcShardChecksums {
+ shard_id: i as u32,
+ covered_size,
+ block_crc32c: packed,
+ });
+ }
+ let prot = EcBitrotProtection {
+ algorithm: ChecksumAlgorithm::ChecksumCrc32c as i32,
+ block_size: DEFAULT_BITROT_BLOCK_SIZE as u32,
+ generation: 0,
+ ec_shard_config: Some(ec_bitrot::ec_shard_config(
+ data_shards as u32,
+ parity_shards as u32,
+ )),
+ shards: shard_checksums,
+ encode_uuid: ec_bitrot::new_encode_uuid(),
+ };
+ let sidecar_path = ec_bitrot::bitrot_sidecar_path(&base, 0);
+ if let Err(e) = ec_bitrot::save_bitrot_sidecar(&sidecar_path, &prot) {
+ // A failed sidecar must not fail the encode — the shards are already
+ // written and valid. The volume simply runs with bitrot protection
+ // off for this generation until the sidecar is regenerated.
+ tracing::warn!(
+ volume_id = volume_id.0,
+ path = %sidecar_path,
+ error = %e,
+ "ec encode: failed to write bitrot sidecar; protection off for this generation",
+ );
+ }
+
Ok(())
}
@@ -536,6 +587,7 @@ fn encode_dat_file(
dat_size: i64,
rs: &ReedSolomon,
shards: &mut [EcVolumeShard],
+ builders: &mut [ShardChecksumBuilder],
data_shards: usize,
parity_shards: usize,
) -> io::Result<()> {
@@ -553,6 +605,7 @@ fn encode_dat_file(
large_block_size,
rs,
shards,
+ builders,
data_shards,
parity_shards,
)?;
@@ -572,6 +625,7 @@ fn encode_dat_file(
small_block_size,
rs,
shards,
+ builders,
data_shards,
parity_shards,
)?;
@@ -589,6 +643,7 @@ fn encode_one_batch(
block_size: usize,
rs: &ReedSolomon,
shards: &mut [EcVolumeShard],
+ builders: &mut [ShardChecksumBuilder],
data_shards: usize,
parity_shards: usize,
) -> io::Result<()> {
@@ -642,9 +697,11 @@ fn encode_one_batch(
)
})?;
- // Write all shard buffers to files
+ // Write all shard buffers to files and feed the same bytes to each
+ // shard's bitrot checksum builder, keeping covered_size == on-disk length.
for (i, buf) in buffers.iter().enumerate() {
shards[i].write_all(buf)?;
+ builders[i].write(buf);
}
Ok(())
@@ -712,6 +769,84 @@ mod tests {
assert!(std::path::Path::new(&ecx_path).exists());
}
+ fn make_volume_with_needles(n: u64) -> TempDir {
+ let tmp = TempDir::new().unwrap();
+ let dir = tmp.path().to_str().unwrap();
+ let mut v = Volume::new(
+ dir,
+ dir,
+ "",
+ VolumeId(1),
+ NeedleMapKind::InMemory,
+ None,
+ None,
+ 0,
+ Version::current(),
+ )
+ .unwrap();
+ for i in 1..=n {
+ // Larger payloads so encoded shards span multiple bitrot blocks
+ // would require huge data; small payloads are fine for correctness.
+ let data = format!("test data for needle {} {}", i, "x".repeat(64));
+ let mut needle = Needle {
+ id: NeedleId(i),
+ cookie: Cookie(i as u32),
+ data: data.as_bytes().to_vec(),
+ data_size: data.len() as u32,
+ ..Needle::default()
+ };
+ v.write_needle(&mut needle, true).unwrap();
+ }
+ v.sync_to_disk().unwrap();
+ v.close();
+ tmp
+ }
+
+ /// Encode-time capture writes a valid generation-0 `.ecsum` sidecar whose
+ /// recorded checksums match the actual on-disk shards.
+ #[test]
+ fn test_encode_writes_valid_bitrot_sidecar() {
+ use crate::storage::erasure_coding::ec_bitrot;
+
+ let tmp = make_volume_with_needles(5);
+ let dir = tmp.path().to_str().unwrap();
+ write_ec_files(dir, dir, "", VolumeId(1), 10, 4).unwrap();
+
+ let base = format!("{}/1", dir);
+ let sidecar_path = ec_bitrot::bitrot_sidecar_path(&base, 0);
+ assert!(
+ std::path::Path::new(&sidecar_path).exists(),
+ "generation-0 .ecsum sidecar should exist after encode"
+ );
+
+ let prot = ec_bitrot::load_bitrot_sidecar(&sidecar_path).unwrap();
+ ec_bitrot::validate_manifest(&prot, 10, 4).unwrap();
+ assert_eq!(prot.generation, 0);
+ assert_eq!(prot.shards.len(), 14);
+ assert_eq!(prot.encode_uuid.len(), 16);
+ assert_eq!(prot.block_size, ec_bitrot::DEFAULT_BITROT_BLOCK_SIZE as u32);
+
+ // Every shard's recorded covered_size must equal its on-disk length and
+ // its block CRCs must verify clean.
+ let bs = prot.block_size as i64;
+ for entry in &prot.shards {
+ let path = format!("{}.ec{:02}", base, entry.shard_id);
+ let on_disk = std::fs::metadata(&path).unwrap().len() as i64;
+ assert_eq!(
+ entry.covered_size, on_disk,
+ "covered_size must equal on-disk length for shard {}",
+ entry.shard_id
+ );
+ let mm = ec_bitrot::verify_shard_file_blocks(&path, entry, bs).unwrap();
+ assert!(
+ mm.is_empty(),
+ "shard {} should verify clean, got mismatches {:?}",
+ entry.shard_id,
+ mm
+ );
+ }
+ }
+
// encode_sample_volume writes a small volume and EC-encodes it, returning
// the dir path so a test can drop/truncate shards and rebuild.
fn encode_sample_volume(tmp: &TempDir) -> String {
diff --git a/seaweed-volume/src/storage/erasure_coding/ec_volume.rs b/seaweed-volume/src/storage/erasure_coding/ec_volume.rs
index eff6d3047..e67418a8b 100644
--- a/seaweed-volume/src/storage/erasure_coding/ec_volume.rs
+++ b/seaweed-volume/src/storage/erasure_coding/ec_volume.rs
@@ -61,6 +61,13 @@ pub struct EcVolume {
/// served from a shard of a different encode run is rejected (server- and
/// client-side); 0 for a pre-feature volume, which is treated leniently.
pub encode_ts_ns: i64,
+ /// Active-generation EC bitrot checksum sidecar (`.ecsum`), loaded and
+ /// validated at mount. `None` unless `bitrot_status == On`.
+ pub(crate) bitrot: Option,
+ /// Resolved protection state of the loaded sidecar. Cached alongside `bitrot`
+ /// so `bitrot_protection()` can return the `Off`/`Invalid` distinction without
+ /// re-reading, mirroring Go's `EcVolume.bitrotStatus`.
+ pub(crate) bitrot_status: crate::storage::erasure_coding::ec_bitrot::BitrotStatus,
}
/// Locate the `.vif` for a (collection, vid) by preferring the data dir
@@ -191,6 +198,8 @@ impl EcVolume {
shard_locations_refresh_time: std::sync::Mutex::new(None),
expire_at_sec,
encode_ts_ns,
+ bitrot: None,
+ bitrot_status: crate::storage::erasure_coding::ec_bitrot::BitrotStatus::Off,
};
// Open .ecx file (sorted index) in read/write mode for in-place deletion marking.
@@ -237,9 +246,189 @@ impl EcVolume {
// Seed the in-memory deleted set from the journal.
vol.load_deleted_needles_from_ecj()?;
+ // Load the generation-0 EC bitrot checksum sidecar (optional; best-effort).
+ vol.load_active_bitrot_sidecar();
+
Ok(vol)
}
+ /// Load the generation-0 checksum sidecar into `self.bitrot`/`self.bitrot_status`.
+ /// OSS only produces generation-0 (fresh-encode) sidecars, mirroring Go's
+ /// `loadActiveBitrotSidecar`.
+ fn load_active_bitrot_sidecar(&mut self) {
+ self.load_bitrot_for_generation(0);
+ }
+
+ /// Load and validate the sidecar describing `generation`, setting
+ /// `self.bitrot`/`self.bitrot_status`. Absent or generation/config-mismatched
+ /// => `Off` (protection off, not corruption); self-integrity or manifest
+ /// failure => `Invalid` with a warning (protection off pending repair); usable
+ /// => `On`. Mirrors Go's `loadBitrotForGeneration`.
+ fn load_bitrot_for_generation(&mut self, generation: u32) {
+ use crate::storage::erasure_coding::ec_bitrot;
+ let base = self.base_name();
+ let path = ec_bitrot::bitrot_sidecar_path(&base, generation);
+ let loaded = ec_bitrot::load_bitrot_sidecar(&path);
+ let status = ec_bitrot::resolve_status(
+ &loaded,
+ generation,
+ self.data_shards as usize,
+ self.parity_shards as usize,
+ );
+ self.bitrot = None;
+ self.bitrot_status = status;
+ match status {
+ ec_bitrot::BitrotStatus::On => self.bitrot = loaded.ok(),
+ ec_bitrot::BitrotStatus::Off => {}
+ ec_bitrot::BitrotStatus::Invalid => {
+ tracing::warn!(
+ volume_id = self.volume_id.0,
+ path = %path,
+ generation,
+ "ec volume: bitrot sidecar present but invalid; protection off pending repair",
+ );
+ }
+ }
+ }
+
+ /// The active-generation bitrot protection AND its status (cached at mount),
+ /// mirroring Go's `EcVolume.BitrotProtection()`. Preserves the distinction
+ /// `checksum_scrub` needs: an absent/generation-mismatched sidecar is `Off`
+ /// (a clean no-op), a present-but-malformed one is `Invalid` (a real integrity
+ /// error). Returns `Some(prot)` only for `On`.
+ pub(crate) fn bitrot_protection(
+ &self,
+ ) -> (
+ Option,
+ crate::storage::erasure_coding::ec_bitrot::BitrotStatus,
+ ) {
+ (self.bitrot.clone(), self.bitrot_status)
+ }
+
+ /// Read-only EC bitrot checksum scrub of the LOCAL shards of this volume's
+ /// active generation.
+ ///
+ /// Loads the active-generation `.ecsum` sidecar and, for each locally-held
+ /// shard, reads the on-disk shard file in `block_size` chunks and compares
+ /// each block's CRC32C against the sidecar. Returns
+ /// `(blocks_scanned, mismatched_shards, errors)`.
+ ///
+ /// If more than `parity_shards` shards mismatch wholesale (i.e. every block
+ /// of those shards is wrong — the signature of a stale/wrong sidecar rather
+ /// than localized disk rot), the result is classified as a suspect sidecar:
+ /// `mismatched_shards` is cleared and an integrity note is added to `errors`
+ /// instead. A genuine multi-shard disk failure of that magnitude is
+ /// already unrecoverable, so treating it as a sidecar-integrity issue avoids
+ /// raising false shard-corruption alarms.
+ ///
+ /// This method NEVER deletes or mutates anything — it is purely diagnostic.
+ pub fn checksum_scrub(&self) -> (u64, Vec, Vec) {
+ use crate::storage::erasure_coding::ec_bitrot;
+ use crate::storage::erasure_coding::ec_bitrot::BitrotStatus;
+
+ let mut errors: Vec = Vec::new();
+
+ // Resolve the active-generation protection AND its status, mirroring
+ // Go's `ChecksumScrub` (`prot, status := ecv.BitrotProtection()`):
+ // - BitrotOff => sidecars are OPTIONAL; an absent (or generation/
+ // config-mismatched) sidecar simply means protection is not enabled
+ // for this generation. Return a CLEAN, EMPTY result — NOT an error —
+ // so legacy/intentionally-unprotected volumes are never reported
+ // broken. (Go: `case BitrotOff: return 0, nil, nil`.)
+ // - BitrotInvalid => the sidecar is PRESENT but malformed/unverifiable
+ // (self-integrity or manifest failure). That is the only status that
+ // yields an integrity error here.
+ // - BitrotOn => scan local shards against it.
+ let prot = match self.bitrot_protection() {
+ (_, BitrotStatus::Off) => {
+ // Unprotected generation: nothing to verify. Not an error.
+ return (0, Vec::new(), Vec::new());
+ }
+ (_, BitrotStatus::Invalid) => {
+ return (
+ 0,
+ Vec::new(),
+ vec![format!(
+ "EC volume {} bitrot sidecar is malformed/unverifiable (sidecar integrity)",
+ self.volume_id.0
+ )],
+ );
+ }
+ (Some(p), BitrotStatus::On) => p,
+ (None, BitrotStatus::On) => {
+ // Unreachable: BitrotOn always carries a loaded sidecar. Treat a
+ // missing payload defensively as protection off (clean no-op).
+ return (0, Vec::new(), Vec::new());
+ }
+ };
+
+ let block_size = prot.block_size as i64;
+ let generation = prot.generation;
+ let base = self.base_name();
+
+ let mut blocks_scanned: u64 = 0;
+ let mut mismatched_shards: Vec = Vec::new();
+ // Track shards whose blocks ALL mismatch (wholesale) to detect a
+ // stale/wrong sidecar.
+ let mut wholesale_mismatch = 0usize;
+
+ for (i, slot) in self.shards.iter().enumerate() {
+ if slot.is_none() {
+ continue; // not local
+ }
+ let shard_id = i as u32;
+ let Some(entry) = ec_bitrot::shard_checksums(&prot, shard_id) else {
+ errors.push(format!(
+ "EC volume {} shard {} present but missing from sidecar manifest",
+ self.volume_id.0, shard_id
+ ));
+ continue;
+ };
+
+ // Resolve the on-disk shard file path for the active generation,
+ // mirroring EcVolumeShard::reopen_against_generation's convention.
+ let path = if generation == 0 {
+ format!("{}.ec{:02}", base, shard_id)
+ } else {
+ format!("{}.ec{:02}.v{}", base, shard_id, generation)
+ };
+
+ let expected_blocks = entry.block_crc32c.len() / 4;
+ match ec_bitrot::verify_shard_file_blocks(&path, entry, block_size) {
+ Ok(mismatched) => {
+ blocks_scanned += expected_blocks as u64;
+ if !mismatched.is_empty() {
+ mismatched_shards.push(shard_id);
+ if expected_blocks > 0 && mismatched.len() == expected_blocks {
+ wholesale_mismatch += 1;
+ }
+ }
+ }
+ Err(e) => {
+ errors.push(format!(
+ "EC volume {} shard {} scrub read error: {}",
+ self.volume_id.0, shard_id, e
+ ));
+ }
+ }
+ }
+
+ // If more shards mismatch wholesale than parity can mask, the sidecar
+ // itself is the likely culprit (stale generation / wrong volume), so
+ // suppress the shard-corruption verdict and flag a sidecar-integrity
+ // issue instead.
+ if wholesale_mismatch > self.parity_shards as usize {
+ errors.push(format!(
+ "EC volume {}: {} shards mismatch wholesale (> {} parity); suspect stale/wrong sidecar, not shard corruption",
+ self.volume_id.0, wholesale_mismatch, self.parity_shards
+ ));
+ mismatched_shards.clear();
+ }
+
+ mismatched_shards.sort_unstable();
+ (blocks_scanned, mismatched_shards, errors)
+ }
+
/// Walk the .ecj journal and populate `deleted_needles`. Called once
/// from `new()` under exclusive ownership of the just-constructed
/// EcVolume, so locking is not strictly required — but we take the
@@ -1274,6 +1463,118 @@ mod tests {
use super::*;
use tempfile::TempDir;
+ /// Mounting an EC volume loads and validates its generation-0 `.ecsum`
+ /// sidecar, so `bitrot_protection()` reports `On` with the parsed manifest.
+ #[test]
+ fn test_mount_loads_bitrot_sidecar() {
+ use crate::storage::erasure_coding::ec_bitrot::BitrotStatus;
+ use crate::storage::needle_map::NeedleMapKind;
+ use crate::storage::volume::Volume;
+
+ let tmp = TempDir::new().unwrap();
+ let dir = tmp.path().to_str().unwrap();
+ let mut v = Volume::new(
+ dir,
+ dir,
+ "",
+ VolumeId(1),
+ NeedleMapKind::InMemory,
+ None,
+ None,
+ 0,
+ Version::current(),
+ )
+ .unwrap();
+ for i in 1..=5 {
+ let data = format!("test data for needle {}", i);
+ let mut n = Needle {
+ id: NeedleId(i),
+ cookie: Cookie(i as u32),
+ data: data.as_bytes().to_vec(),
+ data_size: data.len() as u32,
+ ..Needle::default()
+ };
+ v.write_needle(&mut n, true).unwrap();
+ }
+ v.sync_to_disk().unwrap();
+ v.close();
+ crate::storage::erasure_coding::ec_encoder::write_ec_files(dir, dir, "", VolumeId(1), 10, 4)
+ .unwrap();
+
+ let vol = EcVolume::new(dir, dir, "", VolumeId(1)).unwrap();
+ assert!(
+ vol.bitrot.is_some(),
+ "mount should load the generation-0 .ecsum sidecar"
+ );
+ let (prot, status) = vol.bitrot_protection();
+ assert_eq!(status, BitrotStatus::On);
+ assert_eq!(prot.unwrap().shards.len(), 14);
+ }
+
+ /// CHECKSUM scrub verifies clean shards against the sidecar and flags a shard
+ /// whose bytes are corrupted after encode.
+ #[test]
+ fn test_checksum_scrub_clean_and_detects_corruption() {
+ use crate::storage::needle_map::NeedleMapKind;
+ use crate::storage::volume::Volume;
+
+ let tmp = TempDir::new().unwrap();
+ let dir = tmp.path().to_str().unwrap();
+ let mut v = Volume::new(
+ dir,
+ dir,
+ "",
+ VolumeId(1),
+ NeedleMapKind::InMemory,
+ None,
+ None,
+ 0,
+ Version::current(),
+ )
+ .unwrap();
+ for i in 1..=8 {
+ let data = format!("test data for needle {} with a bit more length", i);
+ let mut n = Needle {
+ id: NeedleId(i),
+ cookie: Cookie(i as u32),
+ data: data.as_bytes().to_vec(),
+ data_size: data.len() as u32,
+ ..Needle::default()
+ };
+ v.write_needle(&mut n, true).unwrap();
+ }
+ v.sync_to_disk().unwrap();
+ v.close();
+ crate::storage::erasure_coding::ec_encoder::write_ec_files(dir, dir, "", VolumeId(1), 10, 4)
+ .unwrap();
+
+ let mut vol = EcVolume::new(dir, dir, "", VolumeId(1)).unwrap();
+ for id in 0..14u8 {
+ vol.add_shard(EcVolumeShard::new(dir, "", VolumeId(1), id))
+ .unwrap();
+ }
+
+ // Clean scrub: no mismatches, no errors, blocks scanned > 0.
+ let (scanned, broken, errs) = vol.checksum_scrub();
+ assert!(errs.is_empty(), "unexpected scrub errors: {:?}", errs);
+ assert!(broken.is_empty(), "unexpected mismatches: {:?}", broken);
+ assert!(scanned > 0, "scrub should scan at least one block");
+
+ // Corrupt one byte of shard 3 on disk; re-scrub must report shard 3.
+ let shard3 = format!("{}/1.ec03", dir);
+ let mut bytes = std::fs::read(&shard3).unwrap();
+ assert!(!bytes.is_empty());
+ bytes[0] ^= 0xFF;
+ std::fs::write(&shard3, &bytes).unwrap();
+
+ let (_, broken2, _) = vol.checksum_scrub();
+ assert!(
+ broken2.contains(&3),
+ "corrupted shard 3 should be flagged, got {:?}",
+ broken2
+ );
+ }
+
fn write_ecx_file(
dir: &str,
collection: &str,
diff --git a/seaweed-volume/src/storage/erasure_coding/mod.rs b/seaweed-volume/src/storage/erasure_coding/mod.rs
index b6c07b450..fd1dab928 100644
--- a/seaweed-volume/src/storage/erasure_coding/mod.rs
+++ b/seaweed-volume/src/storage/erasure_coding/mod.rs
@@ -3,6 +3,7 @@
//! Encodes a volume's .dat file into 10 data + 4 parity shards using
//! Reed-Solomon erasure coding. Can reconstruct from any 10 of 14 shards.
+pub mod ec_bitrot;
pub mod ec_decoder;
pub mod ec_encoder;
pub mod ec_locate;
diff --git a/weed/storage/erasure_coding/ec_bitrot_interop_test.go b/weed/storage/erasure_coding/ec_bitrot_interop_test.go
new file mode 100644
index 000000000..df5ea15c5
--- /dev/null
+++ b/weed/storage/erasure_coding/ec_bitrot_interop_test.go
@@ -0,0 +1,60 @@
+package erasure_coding
+
+import (
+ "encoding/hex"
+ "os"
+ "path/filepath"
+ "testing"
+
+ "github.com/seaweedfs/seaweedfs/weed/pb/volume_server_pb"
+)
+
+// interopSample is the fully-deterministic sidecar shared with the Rust port's
+// ec_bitrot.rs `sample()`. Both binaries must serialize it to identical bytes.
+func interopSample() *volume_server_pb.EcBitrotProtection {
+ return &volume_server_pb.EcBitrotProtection{
+ Algorithm: volume_server_pb.ChecksumAlgorithm_CHECKSUM_CRC32C,
+ BlockSize: uint32(DefaultBitrotBlockSize),
+ EcShardConfig: &volume_server_pb.EcShardConfig{
+ DataShards: 10,
+ ParityShards: 4,
+ },
+ Shards: []*volume_server_pb.EcShardChecksums{
+ {ShardId: 0, CoveredSize: 1024 * 1024, BlockCrc32C: packUint32LE([]uint32{0x01020304})},
+ {ShardId: 1, CoveredSize: 1024 * 1024, BlockCrc32C: packUint32LE([]uint32{0x05060708})},
+ },
+ EncodeUuid: []byte{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15},
+ }
+}
+
+// canonicalInteropHex is the exact on-disk bytes of interopSample(). The Rust
+// port's ec_bitrot.rs test_byte_exact_go_interop pins the SAME constant, so a
+// format change in EITHER binary (new always-serialized field, renumber,
+// EcShardConfig default flip, protobuf canonicalization change) fails that
+// binary's test instead of silently desyncing a Go-written sidecar from a
+// Rust-written one. If you intentionally change the format, regenerate this
+// (run with -v to print the hex) and update the Rust constant in lock-step.
+const canonicalInteropHex = "45435355000100000039cc1b826a080110808080082204080a10042a0a108080401a04040302012a0c0801108080401a04080706053210000102030405060708090a0b0c0d0e0f"
+
+// TestBitrotSidecarBytes_RustInterop pins the on-disk bytes so a Go-side format
+// drift fails here, and the Rust port asserts the same constant (cross-binary
+// sidecar interop).
+func TestBitrotSidecarBytes_RustInterop(t *testing.T) {
+ dir := t.TempDir()
+ path := filepath.Join(dir, "v1.ecsum")
+ if err := SaveBitrotSidecar(path, interopSample()); err != nil {
+ t.Fatalf("save: %v", err)
+ }
+ data, err := os.ReadFile(path)
+ if err != nil {
+ t.Fatalf("read: %v", err)
+ }
+ if got := hex.EncodeToString(data); got != canonicalInteropHex {
+ t.Fatalf("bitrot sidecar bytes drifted from the cross-binary canonical form;\n got=%s\nwant=%s\n(regenerate and update the Rust constant in lock-step)", got, canonicalInteropHex)
+ }
+
+ // Round-trips through the loader.
+ if _, err := LoadBitrotSidecar(path); err != nil {
+ t.Fatalf("load: %v", err)
+ }
+}