Files
rustfs/crates/rio/src/checksum.rs
T

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36 KiB
Rust

// Copyright 2024 RustFS Team
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
use crate::errors::ChecksumMismatch;
use base64::{Engine as _, engine::general_purpose};
use bytes::Bytes;
use http::HeaderMap;
use sha1::Sha1;
use sha2::{Digest, Sha256};
use std::collections::HashMap;
use std::io::Write;
pub const SHA256_SIZE: usize = 32;
/// RustFS multipart checksum metadata key
pub const RUSTFS_MULTIPART_CHECKSUM: &str = "x-rustfs-multipart-checksum";
/// RustFS multipart checksum type metadata key
pub const RUSTFS_MULTIPART_CHECKSUM_TYPE: &str = "x-rustfs-multipart-checksum-type";
/// Checksum type enumeration with flags
#[derive(Debug, Clone, Copy, PartialEq, Eq, Default)]
pub struct ChecksumType(pub u32);
impl ChecksumType {
/// Checksum will be sent in trailing header
pub const TRAILING: ChecksumType = ChecksumType(1 << 0);
/// SHA256 checksum
pub const SHA256: ChecksumType = ChecksumType(1 << 1);
/// SHA1 checksum
pub const SHA1: ChecksumType = ChecksumType(1 << 2);
/// CRC32 checksum with IEEE table
pub const CRC32: ChecksumType = ChecksumType(1 << 3);
/// CRC32 checksum with Castagnoli table
pub const CRC32C: ChecksumType = ChecksumType(1 << 4);
/// Invalid checksum
pub const INVALID: ChecksumType = ChecksumType(1 << 5);
/// Multipart checksum
pub const MULTIPART: ChecksumType = ChecksumType(1 << 6);
/// Checksum includes multipart checksums
pub const INCLUDES_MULTIPART: ChecksumType = ChecksumType(1 << 7);
/// CRC64 with NVME polynomial
pub const CRC64_NVME: ChecksumType = ChecksumType(1 << 8);
/// Full object checksum
pub const FULL_OBJECT: ChecksumType = ChecksumType(1 << 9);
/// No checksum
pub const NONE: ChecksumType = ChecksumType(0);
const BASE_TYPE_MASK: u32 = Self::SHA256.0 | Self::SHA1.0 | Self::CRC32.0 | Self::CRC32C.0 | Self::CRC64_NVME.0;
/// Check if this checksum type has all flags of the given type
pub fn is(self, t: ChecksumType) -> bool {
if t == Self::NONE {
return self == Self::NONE;
}
(self.0 & t.0) == t.0
}
/// Merge another checksum type into this one
pub fn merge(&mut self, other: ChecksumType) -> &mut Self {
self.0 |= other.0;
self
}
/// Get the base checksum type (without flags)
pub fn base(self) -> ChecksumType {
ChecksumType(self.0 & Self::BASE_TYPE_MASK)
}
/// Get the header key for this checksum type
pub fn key(self) -> Option<&'static str> {
match self.base() {
Self::CRC32 => Some("x-amz-checksum-crc32"),
Self::CRC32C => Some("x-amz-checksum-crc32c"),
Self::SHA1 => Some("x-amz-checksum-sha1"),
Self::SHA256 => Some("x-amz-checksum-sha256"),
Self::CRC64_NVME => Some("x-amz-checksum-crc64nvme"),
_ => None,
}
}
/// Get the size of the raw (unencoded) checksum in bytes
pub fn raw_byte_len(self) -> usize {
match self.base() {
Self::CRC32 | Self::CRC32C => 4,
Self::SHA1 => 20,
Self::SHA256 => SHA256_SIZE,
Self::CRC64_NVME => 8,
_ => 0,
}
}
/// Check if the checksum type is set and valid
pub fn is_set(self) -> bool {
!self.is(Self::INVALID) && !self.base().is(Self::NONE)
}
/// Check if this checksum type can be merged
pub fn can_merge(self) -> bool {
self.is(Self::CRC64_NVME) || self.is(Self::CRC32C) || self.is(Self::CRC32)
}
/// Create a hasher for this checksum type
pub fn hasher(self) -> Option<Box<dyn ChecksumHasher>> {
match self.base() {
Self::CRC32 => Some(Box::new(Crc32IeeeHasher::new())),
Self::CRC32C => Some(Box::new(Crc32CastagnoliHasher::new())),
Self::SHA1 => Some(Box::new(Sha1Hasher::new())),
Self::SHA256 => Some(Box::new(Sha256Hasher::new())),
Self::CRC64_NVME => Some(Box::new(Crc64NvmeHasher::new())),
_ => None,
}
}
/// Check if checksum is trailing
pub fn trailing(self) -> bool {
self.is(Self::TRAILING)
}
/// Check if full object checksum was requested
pub fn full_object_requested(self) -> bool {
(self.0 & Self::FULL_OBJECT.0) == Self::FULL_OBJECT.0 || self.is(Self::CRC64_NVME)
}
/// Get object type string for x-amz-checksum-type header
pub fn obj_type(self) -> &'static str {
if self.full_object_requested() {
"FULL_OBJECT"
} else if self.is_set() {
"COMPOSITE"
} else {
""
}
}
pub fn from_header(headers: &HeaderMap) -> Self {
Self::from_string_with_obj_type(
headers
.get("x-amz-checksum-algorithm")
.and_then(|v| v.to_str().ok())
.unwrap_or(""),
headers.get("x-amz-checksum-type").and_then(|v| v.to_str().ok()).unwrap_or(""),
)
}
/// Create checksum type from string algorithm
pub fn from_string(alg: &str) -> Self {
Self::from_string_with_obj_type(alg, "")
}
/// Create checksum type from algorithm and object type
pub fn from_string_with_obj_type(alg: &str, obj_type: &str) -> Self {
let full = match obj_type {
"FULL_OBJECT" => Self::FULL_OBJECT,
"COMPOSITE" | "" => Self::NONE,
_ => return Self::INVALID,
};
match alg.to_uppercase().as_str() {
"CRC32" => ChecksumType(Self::CRC32.0 | full.0),
"CRC32C" => ChecksumType(Self::CRC32C.0 | full.0),
"SHA1" => {
if full != Self::NONE {
return Self::INVALID;
}
Self::SHA1
}
"SHA256" => {
if full != Self::NONE {
return Self::INVALID;
}
Self::SHA256
}
"CRC64NVME" => {
// AWS seems to ignore full value and just assume it
Self::CRC64_NVME
}
"" => {
if full != Self::NONE {
return Self::INVALID;
}
Self::NONE
}
_ => Self::INVALID,
}
}
}
impl std::fmt::Display for ChecksumType {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
match self.base() {
Self::CRC32 => write!(f, "CRC32"),
Self::CRC32C => write!(f, "CRC32C"),
Self::SHA1 => write!(f, "SHA1"),
Self::SHA256 => write!(f, "SHA256"),
Self::CRC64_NVME => write!(f, "CRC64NVME"),
Self::NONE => write!(f, ""),
_ => write!(f, "invalid"),
}
}
}
/// Base checksum types list
pub const BASE_CHECKSUM_TYPES: &[ChecksumType] = &[
ChecksumType::SHA256,
ChecksumType::SHA1,
ChecksumType::CRC32,
ChecksumType::CRC64_NVME,
ChecksumType::CRC32C,
];
/// Checksum structure containing type and encoded value
#[derive(Debug, Clone, PartialEq, Default)]
pub struct Checksum {
pub checksum_type: ChecksumType,
pub encoded: String,
pub raw: Vec<u8>,
pub want_parts: i32,
}
impl Checksum {
/// Create a new checksum from data
pub fn new_from_data(checksum_type: ChecksumType, data: &[u8]) -> Option<Self> {
if !checksum_type.is_set() {
return None;
}
let mut hasher = checksum_type.hasher()?;
hasher.write_all(data).ok()?;
let raw = hasher.finalize();
let encoded = general_purpose::STANDARD.encode(&raw);
let checksum = Checksum {
checksum_type,
encoded,
raw,
want_parts: 0,
};
if checksum.valid() { Some(checksum) } else { None }
}
/// Create a new checksum from algorithm string and base64 value
pub fn new_from_string(alg: &str, value: &str) -> Option<Self> {
Self::new_with_type(ChecksumType::from_string(alg), value)
}
/// Create a new checksum with specific type and value
pub fn new_with_type(mut checksum_type: ChecksumType, value: &str) -> Option<Self> {
if !checksum_type.is_set() {
return None;
}
let mut want_parts = 0;
let value_string;
// Handle multipart format (value-parts)
if value.contains('-') {
let parts: Vec<&str> = value.split('-').collect();
if parts.len() != 2 {
return None;
}
value_string = parts[0].to_string();
want_parts = parts[1].parse().ok()?;
checksum_type = ChecksumType(checksum_type.0 | ChecksumType::MULTIPART.0);
} else {
value_string = value.to_string();
}
// let raw = base64_simd::URL_SAFE_NO_PAD.decode_to_vec(&value_string).ok()?;
let raw = general_purpose::STANDARD.decode(&value_string).ok()?;
let checksum = Checksum {
checksum_type,
encoded: value_string,
raw,
want_parts,
};
if checksum.valid() { Some(checksum) } else { None }
}
/// Check if checksum is valid
pub fn valid(&self) -> bool {
if self.checksum_type == ChecksumType::INVALID {
return false;
}
if self.encoded.is_empty() || self.checksum_type.trailing() {
return self.checksum_type.is(ChecksumType::NONE) || self.checksum_type.trailing();
}
self.checksum_type.raw_byte_len() == self.raw.len()
}
/// Check if content matches this checksum
pub fn matches(&self, content: &[u8], parts: i32) -> Result<(), ChecksumMismatch> {
if self.encoded.is_empty() {
return Ok(());
}
let mut hasher = self.checksum_type.hasher().ok_or_else(|| ChecksumMismatch {
want: self.encoded.clone(),
got: "no hasher available".to_string(),
})?;
hasher.write_all(content).map_err(|_| ChecksumMismatch {
want: self.encoded.clone(),
got: "write error".to_string(),
})?;
let sum = hasher.finalize();
if self.want_parts > 0 && self.want_parts != parts {
return Err(ChecksumMismatch {
want: format!("{}-{}", self.encoded, self.want_parts),
got: format!("{}-{}", general_purpose::STANDARD.encode(&sum), parts),
});
}
if sum != self.raw {
return Err(ChecksumMismatch {
want: self.encoded.clone(),
got: general_purpose::STANDARD.encode(&sum),
});
}
Ok(())
}
/// Convert checksum to map representation
pub fn as_map(&self) -> Option<HashMap<String, String>> {
if !self.valid() {
return None;
}
let mut map = HashMap::new();
map.insert(self.checksum_type.to_string(), self.encoded.clone());
Some(map)
}
pub fn to_bytes(&self, parts: &[u8]) -> Bytes {
self.append_to(Vec::new(), parts).into()
}
/// Append checksum to byte buffer
pub fn append_to(&self, mut buffer: Vec<u8>, parts: &[u8]) -> Vec<u8> {
// Encode checksum type as varint
let mut type_bytes = Vec::new();
encode_varint(&mut type_bytes, self.checksum_type.0 as u64);
buffer.extend_from_slice(&type_bytes);
// Remove trailing flag when serializing
let crc = self.raw.clone();
if self.checksum_type.trailing() {
// When serializing, we don't care if it was trailing
}
if crc.len() != self.checksum_type.raw_byte_len() {
return buffer;
}
buffer.extend_from_slice(&crc);
if self.checksum_type.is(ChecksumType::MULTIPART) {
let mut checksums = 0;
if self.want_parts > 0 && !self.checksum_type.is(ChecksumType::INCLUDES_MULTIPART) {
checksums = self.want_parts;
}
// Ensure we don't divide by 0
let raw_len = self.checksum_type.raw_byte_len();
if raw_len == 0 || !parts.len().is_multiple_of(raw_len) {
checksums = 0;
} else if !parts.is_empty() {
checksums = (parts.len() / raw_len) as i32;
}
let parts_to_append = if self.checksum_type.is(ChecksumType::INCLUDES_MULTIPART) {
parts
} else {
&[]
};
let mut checksums_bytes = Vec::new();
encode_varint(&mut checksums_bytes, checksums as u64);
buffer.extend_from_slice(&checksums_bytes);
if !parts_to_append.is_empty() {
buffer.extend_from_slice(parts_to_append);
}
}
buffer
}
/// Add a part checksum into the current checksum, as if the content of each was appended.
/// The size of the content that produced the second checksum must be provided.
/// Not all checksum types can be merged, use the can_merge method to check.
/// Checksum types must match.
pub fn add_part(&mut self, other: &Checksum, size: i64) -> Result<(), String> {
if !other.checksum_type.can_merge() {
return Err("checksum type cannot be merged".to_string());
}
if size == 0 {
return Ok(());
}
if !self.checksum_type.is(other.checksum_type.base()) {
return Err(format!(
"checksum type does not match got {} and {}",
self.checksum_type, other.checksum_type
));
}
// If never set, just add first checksum
if self.raw.is_empty() {
self.raw = other.raw.clone();
self.encoded = other.encoded.clone();
return Ok(());
}
if !self.valid() {
return Err("invalid base checksum".to_string());
}
if !other.valid() {
return Err("invalid part checksum".to_string());
}
match self.checksum_type.base() {
ChecksumType::CRC32 => {
let crc1 = u32::from_be_bytes([self.raw[0], self.raw[1], self.raw[2], self.raw[3]]);
let crc2 = u32::from_be_bytes([other.raw[0], other.raw[1], other.raw[2], other.raw[3]]);
let combined = crc32_combine(0xEDB88320, crc1, crc2, size); // IEEE polynomial
self.raw = combined.to_be_bytes().to_vec();
}
ChecksumType::CRC32C => {
let crc1 = u32::from_be_bytes([self.raw[0], self.raw[1], self.raw[2], self.raw[3]]);
let crc2 = u32::from_be_bytes([other.raw[0], other.raw[1], other.raw[2], other.raw[3]]);
let combined = crc32_combine(0x82F63B78, crc1, crc2, size); // Castagnoli polynomial
self.raw = combined.to_be_bytes().to_vec();
}
ChecksumType::CRC64_NVME => {
let crc1 = u64::from_be_bytes([
self.raw[0],
self.raw[1],
self.raw[2],
self.raw[3],
self.raw[4],
self.raw[5],
self.raw[6],
self.raw[7],
]);
let crc2 = u64::from_be_bytes([
other.raw[0],
other.raw[1],
other.raw[2],
other.raw[3],
other.raw[4],
other.raw[5],
other.raw[6],
other.raw[7],
]);
let combined = crc64_combine(CRC64_NVME_POLYNOMIAL.reverse_bits(), crc1, crc2, size);
self.raw = combined.to_be_bytes().to_vec();
}
_ => {
return Err(format!("unknown checksum type: {}", self.checksum_type));
}
}
self.encoded = general_purpose::STANDARD.encode(&self.raw);
Ok(())
}
}
/// Get content checksum from headers
pub fn get_content_checksum(headers: &HeaderMap) -> Result<Option<Checksum>, std::io::Error> {
// Check for trailing checksums
if let Some(trailer_header) = headers.get("x-amz-trailer") {
let mut result = None;
let trailer_str = trailer_header
.to_str()
.map_err(|_| std::io::Error::new(std::io::ErrorKind::InvalidData, "Invalid header value"))?;
let trailing_headers: Vec<&str> = trailer_str.split(',').map(|s| s.trim()).collect();
for header in trailing_headers {
let mut duplicates = false;
for &checksum_type in BASE_CHECKSUM_TYPES {
if let Some(key) = checksum_type.key()
&& header.eq_ignore_ascii_case(key)
{
duplicates = result.is_some();
result = Some(Checksum {
checksum_type: ChecksumType(checksum_type.0 | ChecksumType::TRAILING.0),
encoded: String::new(),
raw: Vec::new(),
want_parts: 0,
});
}
}
if duplicates {
return Err(std::io::Error::new(std::io::ErrorKind::InvalidData, "Invalid checksum"));
}
}
if let Some(mut res) = result {
match headers.get("x-amz-checksum-type").and_then(|v| v.to_str().ok()) {
Some("FULL_OBJECT") => {
if !res.checksum_type.can_merge() {
return Err(std::io::Error::new(std::io::ErrorKind::InvalidData, "Invalid checksum"));
}
res.checksum_type = ChecksumType(res.checksum_type.0 | ChecksumType::FULL_OBJECT.0);
}
Some("COMPOSITE") | Some("") | None => {}
_ => return Err(std::io::Error::new(std::io::ErrorKind::InvalidData, "Invalid checksum")),
}
return Ok(Some(res));
}
}
let (checksum_type, value) = get_content_checksum_direct(headers);
if checksum_type == ChecksumType::NONE {
if value.is_empty() {
return Ok(None);
}
return Err(std::io::Error::new(std::io::ErrorKind::InvalidData, "Invalid checksum"));
}
if checksum_type == ChecksumType::INVALID {
return Err(std::io::Error::new(
std::io::ErrorKind::InvalidData,
crate::errors::ChecksumMismatch {
want: "valid checksum header".to_string(),
got: "invalid or duplicate checksum headers".to_string(),
},
));
}
let checksum = Checksum::new_with_type(checksum_type, &value);
if checksum.is_none() && !value.is_empty() {
return Err(std::io::Error::new(
std::io::ErrorKind::InvalidData,
crate::errors::ChecksumMismatch {
want: value,
got: "invalid checksum value".to_string(),
},
));
}
Ok(checksum)
}
/// Get content checksum type and value directly from headers
fn get_content_checksum_direct(headers: &HeaderMap) -> (ChecksumType, String) {
let mut checksum_type = ChecksumType::NONE;
if let Some(alg) = headers.get("x-amz-checksum-algorithm").and_then(|v| v.to_str().ok()) {
checksum_type = ChecksumType::from_string_with_obj_type(
alg,
headers.get("x-amz-checksum-type").and_then(|s| s.to_str().ok()).unwrap_or(""),
);
if headers.get("x-amz-checksum-type").and_then(|v| v.to_str().ok()) == Some("FULL_OBJECT") {
if !checksum_type.can_merge() {
return (ChecksumType::INVALID, String::new());
}
checksum_type = ChecksumType(checksum_type.0 | ChecksumType::FULL_OBJECT.0);
}
if checksum_type.is_set()
&& let Some(key) = checksum_type.key()
{
return if let Some(value) = headers.get(key).and_then(|v| v.to_str().ok()) {
(checksum_type, value.to_string())
} else {
(ChecksumType::NONE, String::new())
};
}
return (checksum_type, String::new());
}
// Check individual checksum headers
for &ct in BASE_CHECKSUM_TYPES {
if let Some(key) = ct.key()
&& let Some(value) = headers.get(key).and_then(|v| v.to_str().ok())
{
// If already set, invalid
if checksum_type != ChecksumType::NONE {
return (ChecksumType::INVALID, String::new());
}
checksum_type = ct;
if headers.get("x-amz-checksum-type").and_then(|v| v.to_str().ok()) == Some("FULL_OBJECT") {
if !checksum_type.can_merge() {
return (ChecksumType::INVALID, String::new());
}
checksum_type = ChecksumType(checksum_type.0 | ChecksumType::FULL_OBJECT.0);
}
return (checksum_type, value.to_string());
}
}
(checksum_type, String::new())
}
/// Trait for checksum hashers
pub trait ChecksumHasher: Write + Send + Sync {
fn finalize(&mut self) -> Vec<u8>;
fn reset(&mut self);
}
/// CRC32 IEEE hasher
pub struct Crc32IeeeHasher {
hasher: crc_fast::Digest,
}
impl Default for Crc32IeeeHasher {
fn default() -> Self {
Self::new()
}
}
impl Crc32IeeeHasher {
pub fn new() -> Self {
Self {
hasher: crc_fast::Digest::new(crc_fast::CrcAlgorithm::Crc32IsoHdlc),
}
}
}
impl Write for Crc32IeeeHasher {
fn write(&mut self, buf: &[u8]) -> std::io::Result<usize> {
self.hasher.update(buf);
Ok(buf.len())
}
fn flush(&mut self) -> std::io::Result<()> {
Ok(())
}
}
impl ChecksumHasher for Crc32IeeeHasher {
fn finalize(&mut self) -> Vec<u8> {
(self.hasher.clone().finalize() as u32).to_be_bytes().to_vec()
}
fn reset(&mut self) {
self.hasher = crc_fast::Digest::new(crc_fast::CrcAlgorithm::Crc32IsoHdlc);
}
}
/// CRC32 Castagnoli hasher
pub struct Crc32CastagnoliHasher {
hasher: crc_fast::Digest,
}
impl Default for Crc32CastagnoliHasher {
fn default() -> Self {
Self::new()
}
}
impl Crc32CastagnoliHasher {
pub fn new() -> Self {
Self {
hasher: crc_fast::Digest::new(crc_fast::CrcAlgorithm::Crc32Iscsi),
}
}
}
impl Write for Crc32CastagnoliHasher {
fn write(&mut self, buf: &[u8]) -> std::io::Result<usize> {
self.hasher.update(buf);
Ok(buf.len())
}
fn flush(&mut self) -> std::io::Result<()> {
Ok(())
}
}
impl ChecksumHasher for Crc32CastagnoliHasher {
fn finalize(&mut self) -> Vec<u8> {
(self.hasher.clone().finalize() as u32).to_be_bytes().to_vec()
}
fn reset(&mut self) {
self.hasher = crc_fast::Digest::new(crc_fast::CrcAlgorithm::Crc32Iscsi);
}
}
/// SHA1 hasher
pub struct Sha1Hasher {
hasher: Sha1,
}
impl Default for Sha1Hasher {
fn default() -> Self {
Self::new()
}
}
impl Sha1Hasher {
pub fn new() -> Self {
Self { hasher: Sha1::new() }
}
}
impl Write for Sha1Hasher {
fn write(&mut self, buf: &[u8]) -> std::io::Result<usize> {
self.hasher.update(buf);
Ok(buf.len())
}
fn flush(&mut self) -> std::io::Result<()> {
Ok(())
}
}
impl ChecksumHasher for Sha1Hasher {
fn finalize(&mut self) -> Vec<u8> {
self.hasher.clone().finalize().to_vec()
}
fn reset(&mut self) {
self.hasher = Sha1::new();
}
}
/// SHA256 hasher
pub struct Sha256Hasher {
hasher: Sha256,
}
impl Default for Sha256Hasher {
fn default() -> Self {
Self::new()
}
}
impl Sha256Hasher {
pub fn new() -> Self {
Self { hasher: Sha256::new() }
}
}
impl Write for Sha256Hasher {
fn write(&mut self, buf: &[u8]) -> std::io::Result<usize> {
self.hasher.update(buf);
Ok(buf.len())
}
fn flush(&mut self) -> std::io::Result<()> {
Ok(())
}
}
impl ChecksumHasher for Sha256Hasher {
fn finalize(&mut self) -> Vec<u8> {
self.hasher.clone().finalize().to_vec()
}
fn reset(&mut self) {
self.hasher = Sha256::new();
}
}
/// CRC64 NVME hasher
pub struct Crc64NvmeHasher {
hasher: crc_fast::Digest,
}
impl Default for Crc64NvmeHasher {
fn default() -> Self {
Self::new()
}
}
impl Crc64NvmeHasher {
pub fn new() -> Self {
Self {
hasher: crc_fast::Digest::new(crc_fast::CrcAlgorithm::Crc64Nvme),
}
}
}
impl Write for Crc64NvmeHasher {
fn write(&mut self, buf: &[u8]) -> std::io::Result<usize> {
self.hasher.update(buf);
Ok(buf.len())
}
fn flush(&mut self) -> std::io::Result<()> {
Ok(())
}
}
impl ChecksumHasher for Crc64NvmeHasher {
fn finalize(&mut self) -> Vec<u8> {
self.hasher.clone().finalize().to_be_bytes().to_vec()
}
fn reset(&mut self) {
self.hasher = crc_fast::Digest::new(crc_fast::CrcAlgorithm::Crc64Nvme);
}
}
/// Encode unsigned integer as varint
fn encode_varint(buf: &mut Vec<u8>, mut value: u64) {
while value >= 0x80 {
buf.push((value as u8) | 0x80);
value >>= 7;
}
buf.push(value as u8);
}
/// Decode varint from buffer
pub fn decode_varint(buf: &[u8]) -> Option<(u64, usize)> {
let mut result = 0u64;
let mut shift = 0;
let mut pos = 0;
for &byte in buf {
pos += 1;
result |= ((byte & 0x7F) as u64) << shift;
if byte & 0x80 == 0 {
return Some((result, pos));
}
shift += 7;
if shift >= 64 {
return None; // Overflow
}
}
None // Incomplete varint
}
/// Read checksums from byte buffer
pub fn read_checksums(mut buf: &[u8], part: i32) -> (HashMap<String, String>, bool) {
let mut result = HashMap::new();
let mut is_multipart = false;
while !buf.is_empty() {
let (checksum_type_val, n) = match decode_varint(buf) {
Some((val, n)) => (val, n),
None => break,
};
buf = &buf[n..];
let checksum_type = ChecksumType(checksum_type_val as u32);
let length = checksum_type.raw_byte_len();
if length == 0 || buf.len() < length {
break;
}
let checksum_bytes = &buf[..length];
buf = &buf[length..];
let mut checksum_str = general_purpose::STANDARD.encode(checksum_bytes);
if checksum_type.is(ChecksumType::MULTIPART) {
is_multipart = true;
let (parts_count, n) = match decode_varint(buf) {
Some((val, n)) => (val, n),
None => break,
};
buf = &buf[n..];
if !checksum_type.full_object_requested() {
checksum_str = format!("{checksum_str}-{parts_count}");
} else if part <= 0 {
result.insert("x-amz-checksum-type".to_string(), "FULL_OBJECT".to_string());
}
if part > 0 {
checksum_str.clear();
}
if checksum_type.is(ChecksumType::INCLUDES_MULTIPART) {
let want_len = parts_count as usize * length;
if buf.len() < want_len {
break;
}
// Read part checksum
if part > 0 && (part as u64) <= parts_count {
let offset = ((part - 1) as usize) * length;
let part_checksum = &buf[offset..offset + length];
checksum_str = general_purpose::STANDARD.encode(part_checksum);
}
buf = &buf[want_len..];
}
} else if part > 1 {
// For non-multipart, checksum is part 1
checksum_str.clear();
}
if !checksum_str.is_empty() {
result.insert(checksum_type.to_string(), checksum_str);
}
}
(result, is_multipart)
}
/// Read all part checksums from buffer
pub fn read_part_checksums(mut buf: &[u8]) -> Vec<HashMap<String, String>> {
let mut result = Vec::new();
while !buf.is_empty() {
let (checksum_type_val, n) = match decode_varint(buf) {
Some((val, n)) => (val, n),
None => break,
};
buf = &buf[n..];
let checksum_type = ChecksumType(checksum_type_val as u32);
let length = checksum_type.raw_byte_len();
if length == 0 || buf.len() < length {
break;
}
// Skip main checksum
buf = &buf[length..];
let (parts_count, n) = match decode_varint(buf) {
Some((val, n)) => (val, n),
None => break,
};
buf = &buf[n..];
if !checksum_type.is(ChecksumType::INCLUDES_MULTIPART) {
continue;
}
if result.is_empty() {
result.resize(parts_count as usize, HashMap::new());
}
for part_checksum in result.iter_mut() {
if buf.len() < length {
break;
}
let checksum_bytes = &buf[..length];
buf = &buf[length..];
let checksum_str = general_purpose::STANDARD.encode(checksum_bytes);
part_checksum.insert(checksum_type.to_string(), checksum_str);
}
}
result
}
/// CRC64 NVME polynomial constant
const CRC64_NVME_POLYNOMIAL: u64 = 0xad93d23594c93659;
/// GF(2) matrix multiplication
fn gf2_matrix_times(mat: &[u64], mut vec: u64) -> u64 {
let mut sum = 0u64;
for &m in mat {
if vec == 0 {
break;
}
if vec & 1 != 0 {
sum ^= m;
}
vec >>= 1;
}
sum
}
/// Square a GF(2) matrix
fn gf2_matrix_square(square: &mut [u64], mat: &[u64]) {
if square.len() != mat.len() {
panic!("square matrix size mismatch");
}
for (i, &m) in mat.iter().enumerate() {
square[i] = gf2_matrix_times(mat, m);
}
}
/// Combine two CRC32 values
///
/// Returns the combined CRC-32 hash value of the two passed CRC-32
/// hash values crc1 and crc2. poly represents the generator polynomial
/// and len2 specifies the byte length that the crc2 hash covers.
fn crc32_combine(poly: u32, crc1: u32, crc2: u32, len2: i64) -> u32 {
// Degenerate case (also disallow negative lengths)
if len2 <= 0 {
return crc1;
}
let mut even = [0u64; 32]; // even-power-of-two zeros operator
let mut odd = [0u64; 32]; // odd-power-of-two zeros operator
// Put operator for one zero bit in odd
odd[0] = poly as u64; // CRC-32 polynomial
let mut row = 1u64;
for (_i, odd_val) in odd.iter_mut().enumerate().skip(1) {
*odd_val = row;
row <<= 1;
}
// Put operator for two zero bits in even
gf2_matrix_square(&mut even, &odd);
// Put operator for four zero bits in odd
gf2_matrix_square(&mut odd, &even);
// Apply len2 zeros to crc1 (first square will put the operator for one
// zero byte, eight zero bits, in even)
let mut crc1n = crc1 as u64;
let mut len2 = len2;
loop {
// Apply zeros operator for this bit of len2
gf2_matrix_square(&mut even, &odd);
if len2 & 1 != 0 {
crc1n = gf2_matrix_times(&even, crc1n);
}
len2 >>= 1;
// If no more bits set, then done
if len2 == 0 {
break;
}
// Another iteration of the loop with odd and even swapped
gf2_matrix_square(&mut odd, &even);
if len2 & 1 != 0 {
crc1n = gf2_matrix_times(&odd, crc1n);
}
len2 >>= 1;
// If no more bits set, then done
if len2 == 0 {
break;
}
}
// Return combined crc
crc1n ^= crc2 as u64;
crc1n as u32
}
/// Combine two CRC64 values
fn crc64_combine(poly: u64, crc1: u64, crc2: u64, len2: i64) -> u64 {
// Degenerate case (also disallow negative lengths)
if len2 <= 0 {
return crc1;
}
let mut even = [0u64; 64]; // even-power-of-two zeros operator
let mut odd = [0u64; 64]; // odd-power-of-two zeros operator
// Put operator for one zero bit in odd
odd[0] = poly; // CRC-64 polynomial
let mut row = 1u64;
for (_i, odd_val) in odd.iter_mut().enumerate().skip(1) {
*odd_val = row;
row <<= 1;
}
// Put operator for two zero bits in even
gf2_matrix_square(&mut even, &odd);
// Put operator for four zero bits in odd
gf2_matrix_square(&mut odd, &even);
// Apply len2 zeros to crc1 (first square will put the operator for one
// zero byte, eight zero bits, in even)
let mut crc1n = crc1;
let mut len2 = len2;
loop {
// Apply zeros operator for this bit of len2
gf2_matrix_square(&mut even, &odd);
if len2 & 1 != 0 {
crc1n = gf2_matrix_times(&even, crc1n);
}
len2 >>= 1;
// If no more bits set, then done
if len2 == 0 {
break;
}
// Another iteration of the loop with odd and even swapped
gf2_matrix_square(&mut odd, &even);
if len2 & 1 != 0 {
crc1n = gf2_matrix_times(&odd, crc1n);
}
len2 >>= 1;
// If no more bits set, then done
if len2 == 0 {
break;
}
}
// Return combined crc
crc1n ^ crc2
}
#[cfg(test)]
mod tests {
use super::{Checksum, ChecksumType};
#[test]
fn crc64_nvme_add_part_matches_full_object_checksum() {
let data = (0..200_000).map(|i| (i % 251) as u8).collect::<Vec<_>>();
let split_at = 73_421;
let (first, second) = data.split_at(split_at);
let expected = Checksum::new_from_data(ChecksumType::CRC64_NVME, &data).expect("full checksum");
let first_checksum = Checksum::new_from_data(ChecksumType::CRC64_NVME, first).expect("first checksum");
let second_checksum = Checksum::new_from_data(ChecksumType::CRC64_NVME, second).expect("second checksum");
let mut combined = Checksum {
checksum_type: ChecksumType::CRC64_NVME,
..Default::default()
};
combined
.add_part(&first_checksum, first.len() as i64)
.expect("add first part");
combined
.add_part(&second_checksum, second.len() as i64)
.expect("add second part");
assert_eq!(combined.encoded, expected.encoded);
assert_eq!(combined.raw, expected.raw);
}
#[test]
fn crc32c_add_part_matches_full_object_checksum() {
let data = (0..32_768).map(|i| (255 - (i % 251)) as u8).collect::<Vec<_>>();
let (first, rest) = data.split_at(7_777);
let (second, third) = rest.split_at(13_333);
let expected = Checksum::new_from_data(ChecksumType::CRC32C, &data).expect("full checksum");
let first_checksum = Checksum::new_from_data(ChecksumType::CRC32C, first).expect("first checksum");
let second_checksum = Checksum::new_from_data(ChecksumType::CRC32C, second).expect("second checksum");
let third_checksum = Checksum::new_from_data(ChecksumType::CRC32C, third).expect("third checksum");
let mut combined = Checksum {
checksum_type: ChecksumType::CRC32C,
..Default::default()
};
combined
.add_part(&first_checksum, first.len() as i64)
.expect("add first part");
combined
.add_part(&second_checksum, second.len() as i64)
.expect("add second part");
combined
.add_part(&third_checksum, third.len() as i64)
.expect("add third part");
assert_eq!(combined.encoded, expected.encoded);
assert_eq!(combined.raw, expected.raw);
}
}