minio/cmd/object-api-utils.go
Harshavardhana 4223ebab8d
fix: remove auto-close GetObjectReader (#12009)
locks can get relinquished when Read() sees io.EOF
leading to prematurely closing of the readers

concurrent writes on the same object can have
undesired consequences here when these locks
are relinquished.
2021-04-07 13:29:27 -07:00

988 lines
29 KiB
Go

/*
* MinIO Cloud Storage, (C) 2015-2019 MinIO, Inc.
*
* 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.
*/
package cmd
import (
"bytes"
"context"
"encoding/hex"
"errors"
"fmt"
"io"
"math/rand"
"net"
"net/http"
"path"
"runtime"
"strconv"
"strings"
"sync"
"time"
"unicode/utf8"
"github.com/google/uuid"
"github.com/klauspost/compress/s2"
"github.com/klauspost/readahead"
"github.com/minio/minio-go/v7/pkg/s3utils"
"github.com/minio/minio/cmd/config/compress"
"github.com/minio/minio/cmd/config/dns"
"github.com/minio/minio/cmd/config/storageclass"
"github.com/minio/minio/cmd/crypto"
xhttp "github.com/minio/minio/cmd/http"
"github.com/minio/minio/cmd/logger"
"github.com/minio/minio/pkg/bucket/lifecycle"
"github.com/minio/minio/pkg/hash"
"github.com/minio/minio/pkg/ioutil"
"github.com/minio/minio/pkg/trie"
"github.com/minio/minio/pkg/wildcard"
)
const (
// MinIO meta bucket.
minioMetaBucket = ".minio.sys"
// Multipart meta prefix.
mpartMetaPrefix = "multipart"
// MinIO Multipart meta prefix.
minioMetaMultipartBucket = minioMetaBucket + SlashSeparator + mpartMetaPrefix
// MinIO tmp meta prefix.
minioMetaTmpBucket = minioMetaBucket + "/tmp"
// MinIO tmp meta prefix for deleted objects.
minioMetaTmpDeletedBucket = minioMetaTmpBucket + "/.trash"
// DNS separator (period), used for bucket name validation.
dnsDelimiter = "."
// On compressed files bigger than this;
compReadAheadSize = 100 << 20
// Read this many buffers ahead.
compReadAheadBuffers = 5
// Size of each buffer.
compReadAheadBufSize = 1 << 20
)
// isMinioBucket returns true if given bucket is a MinIO internal
// bucket and false otherwise.
func isMinioMetaBucketName(bucket string) bool {
return bucket == minioMetaBucket ||
bucket == minioMetaMultipartBucket ||
bucket == minioMetaTmpBucket ||
bucket == dataUsageBucket
}
// IsValidBucketName verifies that a bucket name is in accordance with
// Amazon's requirements (i.e. DNS naming conventions). It must be 3-63
// characters long, and it must be a sequence of one or more labels
// separated by periods. Each label can contain lowercase ascii
// letters, decimal digits and hyphens, but must not begin or end with
// a hyphen. See:
// http://docs.aws.amazon.com/AmazonS3/latest/dev/BucketRestrictions.html
func IsValidBucketName(bucket string) bool {
// Special case when bucket is equal to one of the meta buckets.
if isMinioMetaBucketName(bucket) {
return true
}
if len(bucket) < 3 || len(bucket) > 63 {
return false
}
// Split on dot and check each piece conforms to rules.
allNumbers := true
pieces := strings.Split(bucket, dnsDelimiter)
for _, piece := range pieces {
if len(piece) == 0 || piece[0] == '-' ||
piece[len(piece)-1] == '-' {
// Current piece has 0-length or starts or
// ends with a hyphen.
return false
}
// Now only need to check if each piece is a valid
// 'label' in AWS terminology and if the bucket looks
// like an IP address.
isNotNumber := false
for i := 0; i < len(piece); i++ {
switch {
case (piece[i] >= 'a' && piece[i] <= 'z' ||
piece[i] == '-'):
// Found a non-digit character, so
// this piece is not a number.
isNotNumber = true
case piece[i] >= '0' && piece[i] <= '9':
// Nothing to do.
default:
// Found invalid character.
return false
}
}
allNumbers = allNumbers && !isNotNumber
}
// Does the bucket name look like an IP address?
return !(len(pieces) == 4 && allNumbers)
}
// IsValidObjectName verifies an object name in accordance with Amazon's
// requirements. It cannot exceed 1024 characters and must be a valid UTF8
// string.
//
// See:
// http://docs.aws.amazon.com/AmazonS3/latest/dev/UsingMetadata.html
//
// You should avoid the following characters in a key name because of
// significant special handling for consistency across all
// applications.
//
// Rejects strings with following characters.
//
// - Backslash ("\")
//
// additionally minio does not support object names with trailing SlashSeparator.
func IsValidObjectName(object string) bool {
if len(object) == 0 {
return false
}
if HasSuffix(object, SlashSeparator) {
return false
}
return IsValidObjectPrefix(object)
}
// IsValidObjectPrefix verifies whether the prefix is a valid object name.
// Its valid to have a empty prefix.
func IsValidObjectPrefix(object string) bool {
if hasBadPathComponent(object) {
return false
}
if !utf8.ValidString(object) {
return false
}
if strings.Contains(object, `//`) {
return false
}
return true
}
// checkObjectNameForLengthAndSlash -check for the validity of object name length and prefis as slash
func checkObjectNameForLengthAndSlash(bucket, object string) error {
// Check for the length of object name
if len(object) > 1024 {
return ObjectNameTooLong{
Bucket: bucket,
Object: object,
}
}
// Check for slash as prefix in object name
if HasPrefix(object, SlashSeparator) {
return ObjectNamePrefixAsSlash{
Bucket: bucket,
Object: object,
}
}
if runtime.GOOS == globalWindowsOSName {
// Explicitly disallowed characters on windows.
// Avoids most problematic names.
if strings.ContainsAny(object, `:*?"|<>`) {
return ObjectNameInvalid{
Bucket: bucket,
Object: object,
}
}
}
return nil
}
// SlashSeparator - slash separator.
const SlashSeparator = "/"
// retainSlash - retains slash from a path.
func retainSlash(s string) string {
if s == "" {
return s
}
return strings.TrimSuffix(s, SlashSeparator) + SlashSeparator
}
// pathsJoinPrefix - like pathJoin retains trailing SlashSeparator
// for all elements, prepends them with 'prefix' respectively.
func pathsJoinPrefix(prefix string, elem ...string) (paths []string) {
paths = make([]string, len(elem))
for i, e := range elem {
paths[i] = pathJoin(prefix, e)
}
return paths
}
// pathJoin - like path.Join() but retains trailing SlashSeparator of the last element
func pathJoin(elem ...string) string {
trailingSlash := ""
if len(elem) > 0 {
if HasSuffix(elem[len(elem)-1], SlashSeparator) {
trailingSlash = SlashSeparator
}
}
return path.Join(elem...) + trailingSlash
}
// mustGetUUID - get a random UUID.
func mustGetUUID() string {
u, err := uuid.NewRandom()
if err != nil {
logger.CriticalIf(GlobalContext, err)
}
return u.String()
}
// Create an s3 compatible MD5sum for complete multipart transaction.
func getCompleteMultipartMD5(parts []CompletePart) string {
var finalMD5Bytes []byte
for _, part := range parts {
md5Bytes, err := hex.DecodeString(canonicalizeETag(part.ETag))
if err != nil {
finalMD5Bytes = append(finalMD5Bytes, []byte(part.ETag)...)
} else {
finalMD5Bytes = append(finalMD5Bytes, md5Bytes...)
}
}
s3MD5 := fmt.Sprintf("%s-%d", getMD5Hash(finalMD5Bytes), len(parts))
return s3MD5
}
// Clean unwanted fields from metadata
func cleanMetadata(metadata map[string]string) map[string]string {
// Remove STANDARD StorageClass
metadata = removeStandardStorageClass(metadata)
// Clean meta etag keys 'md5Sum', 'etag', "expires", "x-amz-tagging".
return cleanMetadataKeys(metadata, "md5Sum", "etag", "expires", xhttp.AmzObjectTagging, "last-modified")
}
// Filter X-Amz-Storage-Class field only if it is set to STANDARD.
// This is done since AWS S3 doesn't return STANDARD Storage class as response header.
func removeStandardStorageClass(metadata map[string]string) map[string]string {
if metadata[xhttp.AmzStorageClass] == storageclass.STANDARD {
delete(metadata, xhttp.AmzStorageClass)
}
return metadata
}
// cleanMetadataKeys takes keyNames to be filtered
// and returns a new map with all the entries with keyNames removed.
func cleanMetadataKeys(metadata map[string]string, keyNames ...string) map[string]string {
var newMeta = make(map[string]string, len(metadata))
for k, v := range metadata {
if contains(keyNames, k) {
continue
}
newMeta[k] = v
}
return newMeta
}
// Extracts etag value from the metadata.
func extractETag(metadata map[string]string) string {
// md5Sum tag is kept for backward compatibility.
etag, ok := metadata["md5Sum"]
if !ok {
etag = metadata["etag"]
}
// Success.
return etag
}
// HasPrefix - Prefix matcher string matches prefix in a platform specific way.
// For example on windows since its case insensitive we are supposed
// to do case insensitive checks.
func HasPrefix(s string, prefix string) bool {
if runtime.GOOS == globalWindowsOSName {
return strings.HasPrefix(strings.ToLower(s), strings.ToLower(prefix))
}
return strings.HasPrefix(s, prefix)
}
// HasSuffix - Suffix matcher string matches suffix in a platform specific way.
// For example on windows since its case insensitive we are supposed
// to do case insensitive checks.
func HasSuffix(s string, suffix string) bool {
if runtime.GOOS == globalWindowsOSName {
return strings.HasSuffix(strings.ToLower(s), strings.ToLower(suffix))
}
return strings.HasSuffix(s, suffix)
}
// Validates if two strings are equal.
func isStringEqual(s1 string, s2 string) bool {
if runtime.GOOS == globalWindowsOSName {
return strings.EqualFold(s1, s2)
}
return s1 == s2
}
// Ignores all reserved bucket names or invalid bucket names.
func isReservedOrInvalidBucket(bucketEntry string, strict bool) bool {
if bucketEntry == "" {
return true
}
bucketEntry = strings.TrimSuffix(bucketEntry, SlashSeparator)
if strict {
if err := s3utils.CheckValidBucketNameStrict(bucketEntry); err != nil {
return true
}
} else {
if err := s3utils.CheckValidBucketName(bucketEntry); err != nil {
return true
}
}
return isMinioMetaBucket(bucketEntry) || isMinioReservedBucket(bucketEntry)
}
// Returns true if input bucket is a reserved minio meta bucket '.minio.sys'.
func isMinioMetaBucket(bucketName string) bool {
return bucketName == minioMetaBucket
}
// Returns true if input bucket is a reserved minio bucket 'minio'.
func isMinioReservedBucket(bucketName string) bool {
return bucketName == minioReservedBucket
}
// returns a slice of hosts by reading a slice of DNS records
func getHostsSlice(records []dns.SrvRecord) []string {
hosts := make([]string, len(records))
for i, r := range records {
hosts[i] = net.JoinHostPort(r.Host, string(r.Port))
}
return hosts
}
// returns an online host (and corresponding port) from a slice of DNS records
func getHostFromSrv(records []dns.SrvRecord) (host string) {
hosts := getHostsSlice(records)
rng := rand.New(rand.NewSource(time.Now().UTC().UnixNano()))
var d net.Dialer
var retry int
for retry < len(hosts) {
ctx, cancel := context.WithTimeout(GlobalContext, 300*time.Millisecond)
host = hosts[rng.Intn(len(hosts))]
conn, err := d.DialContext(ctx, "tcp", host)
cancel()
if err != nil {
retry++
continue
}
conn.Close()
break
}
return host
}
// IsCompressed returns true if the object is marked as compressed.
func (o ObjectInfo) IsCompressed() bool {
_, ok := o.UserDefined[ReservedMetadataPrefix+"compression"]
return ok
}
// IsCompressedOK returns whether the object is compressed and can be decompressed.
func (o ObjectInfo) IsCompressedOK() (bool, error) {
scheme, ok := o.UserDefined[ReservedMetadataPrefix+"compression"]
if !ok {
return false, nil
}
switch scheme {
case compressionAlgorithmV1, compressionAlgorithmV2:
return true, nil
}
return true, fmt.Errorf("unknown compression scheme: %s", scheme)
}
// GetActualETag - returns the actual etag of the stored object
// decrypts SSE objects.
func (o ObjectInfo) GetActualETag(h http.Header) string {
if _, ok := crypto.IsEncrypted(o.UserDefined); !ok {
return o.ETag
}
return getDecryptedETag(h, o, false)
}
// GetActualSize - returns the actual size of the stored object
func (o ObjectInfo) GetActualSize() (int64, error) {
if o.IsCompressed() {
sizeStr, ok := o.UserDefined[ReservedMetadataPrefix+"actual-size"]
if !ok {
return -1, errInvalidDecompressedSize
}
size, err := strconv.ParseInt(sizeStr, 10, 64)
if err != nil {
return -1, errInvalidDecompressedSize
}
return size, nil
}
if _, ok := crypto.IsEncrypted(o.UserDefined); ok {
return o.DecryptedSize()
}
return o.Size, nil
}
// Disabling compression for encrypted enabled requests.
// Using compression and encryption together enables room for side channel attacks.
// Eliminate non-compressible objects by extensions/content-types.
func isCompressible(header http.Header, object string) bool {
globalCompressConfigMu.Lock()
cfg := globalCompressConfig
globalCompressConfigMu.Unlock()
_, ok := crypto.IsRequested(header)
if !cfg.Enabled || (ok && !cfg.AllowEncrypted) || excludeForCompression(header, object, cfg) {
return false
}
return true
}
// Eliminate the non-compressible objects.
func excludeForCompression(header http.Header, object string, cfg compress.Config) bool {
objStr := object
contentType := header.Get(xhttp.ContentType)
if !cfg.Enabled {
return true
}
// We strictly disable compression for standard extensions/content-types (`compressed`).
if hasStringSuffixInSlice(objStr, standardExcludeCompressExtensions) || hasPattern(standardExcludeCompressContentTypes, contentType) {
return true
}
// Filter compression includes.
exclude := len(cfg.Extensions) > 0 || len(cfg.MimeTypes) > 0
if len(cfg.Extensions) > 0 && hasStringSuffixInSlice(objStr, cfg.Extensions) {
exclude = false
}
if len(cfg.MimeTypes) > 0 && hasPattern(cfg.MimeTypes, contentType) {
exclude = false
}
return exclude
}
// Utility which returns if a string is present in the list.
// Comparison is case insensitive.
func hasStringSuffixInSlice(str string, list []string) bool {
str = strings.ToLower(str)
for _, v := range list {
if strings.HasSuffix(str, strings.ToLower(v)) {
return true
}
}
return false
}
// Returns true if any of the given wildcard patterns match the matchStr.
func hasPattern(patterns []string, matchStr string) bool {
for _, pattern := range patterns {
if ok := wildcard.MatchSimple(pattern, matchStr); ok {
return true
}
}
return false
}
// Returns the part file name which matches the partNumber and etag.
func getPartFile(entriesTrie *trie.Trie, partNumber int, etag string) (partFile string) {
for _, match := range entriesTrie.PrefixMatch(fmt.Sprintf("%.5d.%s.", partNumber, etag)) {
partFile = match
break
}
return partFile
}
func partNumberToRangeSpec(oi ObjectInfo, partNumber int) *HTTPRangeSpec {
if oi.Size == 0 || len(oi.Parts) == 0 {
return nil
}
var start int64
var end = int64(-1)
for i := 0; i < len(oi.Parts) && i < partNumber; i++ {
start = end + 1
end = start + oi.Parts[i].ActualSize - 1
}
return &HTTPRangeSpec{Start: start, End: end}
}
// Returns the compressed offset which should be skipped.
// If encrypted offsets are adjusted for encrypted block headers/trailers.
// Since de-compression is after decryption encryption overhead is only added to compressedOffset.
func getCompressedOffsets(objectInfo ObjectInfo, offset int64) (compressedOffset int64, partSkip int64, firstPart int) {
var skipLength int64
var cumulativeActualSize int64
var firstPartIdx int
if len(objectInfo.Parts) > 0 {
for i, part := range objectInfo.Parts {
cumulativeActualSize += part.ActualSize
if cumulativeActualSize <= offset {
compressedOffset += part.Size
} else {
firstPartIdx = i
skipLength = cumulativeActualSize - part.ActualSize
break
}
}
}
if isEncryptedMultipart(objectInfo) && firstPartIdx > 0 {
off, _, _, _, _, err := objectInfo.GetDecryptedRange(partNumberToRangeSpec(objectInfo, firstPartIdx))
logger.LogIf(context.Background(), err)
compressedOffset += off
}
return compressedOffset, offset - skipLength, firstPartIdx
}
// GetObjectReader is a type that wraps a reader with a lock to
// provide a ReadCloser interface that unlocks on Close()
type GetObjectReader struct {
ObjInfo ObjectInfo
pReader io.Reader
cleanUpFns []func()
opts ObjectOptions
once sync.Once
}
// NewGetObjectReaderFromReader sets up a GetObjectReader with a given
// reader. This ignores any object properties.
func NewGetObjectReaderFromReader(r io.Reader, oi ObjectInfo, opts ObjectOptions, cleanupFns ...func()) (*GetObjectReader, error) {
if opts.CheckPrecondFn != nil && opts.CheckPrecondFn(oi) {
// Call the cleanup funcs
for i := len(cleanupFns) - 1; i >= 0; i-- {
cleanupFns[i]()
}
return nil, PreConditionFailed{}
}
return &GetObjectReader{
ObjInfo: oi,
pReader: r,
cleanUpFns: cleanupFns,
opts: opts,
}, nil
}
// ObjReaderFn is a function type that takes a reader and returns
// GetObjectReader and an error. Request headers are passed to provide
// encryption parameters. cleanupFns allow cleanup funcs to be
// registered for calling after usage of the reader.
type ObjReaderFn func(inputReader io.Reader, h http.Header, pcfn CheckPreconditionFn, cleanupFns ...func()) (r *GetObjectReader, err error)
// NewGetObjectReader creates a new GetObjectReader. The cleanUpFns
// are called on Close() in reverse order as passed here. NOTE: It is
// assumed that clean up functions do not panic (otherwise, they may
// not all run!).
func NewGetObjectReader(rs *HTTPRangeSpec, oi ObjectInfo, opts ObjectOptions, cleanUpFns ...func()) (
fn ObjReaderFn, off, length int64, err error) {
if rs == nil && opts.PartNumber > 0 {
rs = partNumberToRangeSpec(oi, opts.PartNumber)
}
// Call the clean-up functions immediately in case of exit
// with error
defer func() {
if err != nil {
for i := len(cleanUpFns) - 1; i >= 0; i-- {
cleanUpFns[i]()
}
}
}()
_, isEncrypted := crypto.IsEncrypted(oi.UserDefined)
isCompressed, err := oi.IsCompressedOK()
if err != nil {
return nil, 0, 0, err
}
// if object is encrypted, transition content without decrypting.
if opts.TransitionStatus == lifecycle.TransitionPending && (isEncrypted || isCompressed) {
isEncrypted = false
isCompressed = false
}
// Calculate range to read (different for encrypted/compressed objects)
switch {
case isCompressed:
var firstPart int
if opts.PartNumber > 0 {
// firstPart is an index to Parts slice,
// make sure that PartNumber uses the
// index value properly.
firstPart = opts.PartNumber - 1
}
// If compressed, we start from the beginning of the part.
// Read the decompressed size from the meta.json.
actualSize, err := oi.GetActualSize()
if err != nil {
return nil, 0, 0, err
}
off, length = int64(0), oi.Size
decOff, decLength := int64(0), actualSize
if rs != nil {
off, length, err = rs.GetOffsetLength(actualSize)
if err != nil {
return nil, 0, 0, err
}
// In case of range based queries on multiparts, the offset and length are reduced.
off, decOff, firstPart = getCompressedOffsets(oi, off)
decLength = length
length = oi.Size - off
// For negative length we read everything.
if decLength < 0 {
decLength = actualSize - decOff
}
// Reply back invalid range if the input offset and length fall out of range.
if decOff > actualSize || decOff+decLength > actualSize {
return nil, 0, 0, errInvalidRange
}
}
fn = func(inputReader io.Reader, h http.Header, pcfn CheckPreconditionFn, cFns ...func()) (r *GetObjectReader, err error) {
cFns = append(cleanUpFns, cFns...)
if opts.CheckPrecondFn != nil && opts.CheckPrecondFn(oi) {
// Call the cleanup funcs
for i := len(cFns) - 1; i >= 0; i-- {
cFns[i]()
}
return nil, PreConditionFailed{}
}
if isEncrypted {
copySource := h.Get(xhttp.AmzServerSideEncryptionCopyCustomerAlgorithm) != ""
// Attach decrypter on inputReader
inputReader, err = DecryptBlocksRequestR(inputReader, h, 0, firstPart, oi, copySource)
if err != nil {
// Call the cleanup funcs
for i := len(cFns) - 1; i >= 0; i-- {
cFns[i]()
}
return nil, err
}
oi.Size = decLength
}
// Decompression reader.
s2Reader := s2.NewReader(inputReader)
// Apply the skipLen and limit on the decompressed stream.
if decOff > 0 {
if err = s2Reader.Skip(decOff); err != nil {
// Call the cleanup funcs
for i := len(cFns) - 1; i >= 0; i-- {
cFns[i]()
}
return nil, err
}
}
decReader := io.LimitReader(s2Reader, decLength)
if decLength > compReadAheadSize {
rah, err := readahead.NewReaderSize(decReader, compReadAheadBuffers, compReadAheadBufSize)
if err == nil {
decReader = rah
cFns = append(cFns, func() {
rah.Close()
})
}
}
oi.Size = decLength
// Assemble the GetObjectReader
r = &GetObjectReader{
ObjInfo: oi,
pReader: decReader,
cleanUpFns: cFns,
opts: opts,
}
return r, nil
}
case isEncrypted:
var seqNumber uint32
var partStart int
var skipLen int64
off, length, skipLen, seqNumber, partStart, err = oi.GetDecryptedRange(rs)
if err != nil {
return nil, 0, 0, err
}
var decSize int64
decSize, err = oi.DecryptedSize()
if err != nil {
return nil, 0, 0, err
}
var decRangeLength int64
decRangeLength, err = rs.GetLength(decSize)
if err != nil {
return nil, 0, 0, err
}
// We define a closure that performs decryption given
// a reader that returns the desired range of
// encrypted bytes. The header parameter is used to
// provide encryption parameters.
fn = func(inputReader io.Reader, h http.Header, pcfn CheckPreconditionFn, cFns ...func()) (r *GetObjectReader, err error) {
copySource := h.Get(xhttp.AmzServerSideEncryptionCopyCustomerAlgorithm) != ""
cFns = append(cleanUpFns, cFns...)
// Attach decrypter on inputReader
var decReader io.Reader
decReader, err = DecryptBlocksRequestR(inputReader, h, seqNumber, partStart, oi, copySource)
if err != nil {
// Call the cleanup funcs
for i := len(cFns) - 1; i >= 0; i-- {
cFns[i]()
}
return nil, err
}
if opts.CheckPrecondFn != nil && opts.CheckPrecondFn(oi) {
// Call the cleanup funcs
for i := len(cFns) - 1; i >= 0; i-- {
cFns[i]()
}
return nil, PreConditionFailed{}
}
oi.ETag = getDecryptedETag(h, oi, false)
// Apply the skipLen and limit on the
// decrypted stream
decReader = io.LimitReader(ioutil.NewSkipReader(decReader, skipLen), decRangeLength)
// Assemble the GetObjectReader
r = &GetObjectReader{
ObjInfo: oi,
pReader: decReader,
cleanUpFns: cFns,
opts: opts,
}
return r, nil
}
default:
off, length, err = rs.GetOffsetLength(oi.Size)
if err != nil {
return nil, 0, 0, err
}
fn = func(inputReader io.Reader, _ http.Header, pcfn CheckPreconditionFn, cFns ...func()) (r *GetObjectReader, err error) {
cFns = append(cleanUpFns, cFns...)
if opts.CheckPrecondFn != nil && opts.CheckPrecondFn(oi) {
// Call the cleanup funcs
for i := len(cFns) - 1; i >= 0; i-- {
cFns[i]()
}
return nil, PreConditionFailed{}
}
r = &GetObjectReader{
ObjInfo: oi,
pReader: inputReader,
cleanUpFns: cFns,
opts: opts,
}
return r, nil
}
}
return fn, off, length, nil
}
// Close - calls the cleanup actions in reverse order
func (g *GetObjectReader) Close() error {
// sync.Once is used here to ensure that Close() is
// idempotent.
g.once.Do(func() {
for i := len(g.cleanUpFns) - 1; i >= 0; i-- {
g.cleanUpFns[i]()
}
})
return nil
}
// Read - to implement Reader interface.
func (g *GetObjectReader) Read(p []byte) (n int, err error) {
return g.pReader.Read(p)
}
//SealMD5CurrFn seals md5sum with object encryption key and returns sealed
// md5sum
type SealMD5CurrFn func([]byte) []byte
// PutObjReader is a type that wraps sio.EncryptReader and
// underlying hash.Reader in a struct
type PutObjReader struct {
*hash.Reader // actual data stream
rawReader *hash.Reader // original data stream
sealMD5Fn SealMD5CurrFn
}
// Size returns the absolute number of bytes the Reader
// will return during reading. It returns -1 for unlimited
// data.
func (p *PutObjReader) Size() int64 {
return p.Reader.Size()
}
// MD5CurrentHexString returns the current MD5Sum or encrypted MD5Sum
// as a hex encoded string
func (p *PutObjReader) MD5CurrentHexString() string {
md5sumCurr := p.rawReader.MD5Current()
var appendHyphen bool
// md5sumcurr is not empty in two scenarios
// - server is running in strict compatibility mode
// - client set Content-Md5 during PUT operation
if len(md5sumCurr) == 0 {
// md5sumCurr is only empty when we are running
// in non-compatibility mode.
md5sumCurr = make([]byte, 16)
rand.Read(md5sumCurr)
appendHyphen = true
}
if p.sealMD5Fn != nil {
md5sumCurr = p.sealMD5Fn(md5sumCurr)
}
if appendHyphen {
// Make sure to return etag string upto 32 length, for SSE
// requests ETag might be longer and the code decrypting the
// ETag ignores ETag in multipart ETag form i.e <hex>-N
return hex.EncodeToString(md5sumCurr)[:32] + "-1"
}
return hex.EncodeToString(md5sumCurr)
}
// WithEncryption sets up encrypted reader and the sealing for content md5sum
// using objEncKey. Unsealed md5sum is computed from the rawReader setup when
// NewPutObjReader was called. It returns an error if called on an uninitialized
// PutObjReader.
func (p *PutObjReader) WithEncryption(encReader *hash.Reader, objEncKey *crypto.ObjectKey) (*PutObjReader, error) {
if p.Reader == nil {
return nil, errors.New("put-object reader uninitialized")
}
p.Reader = encReader
p.sealMD5Fn = sealETagFn(*objEncKey)
return p, nil
}
// NewPutObjReader returns a new PutObjReader. It uses given hash.Reader's
// MD5Current method to construct md5sum when requested downstream.
func NewPutObjReader(rawReader *hash.Reader) *PutObjReader {
return &PutObjReader{Reader: rawReader, rawReader: rawReader}
}
func sealETag(encKey crypto.ObjectKey, md5CurrSum []byte) []byte {
var emptyKey [32]byte
if bytes.Equal(encKey[:], emptyKey[:]) {
return md5CurrSum
}
return encKey.SealETag(md5CurrSum)
}
func sealETagFn(key crypto.ObjectKey) SealMD5CurrFn {
fn := func(md5sumcurr []byte) []byte {
return sealETag(key, md5sumcurr)
}
return fn
}
// CleanMinioInternalMetadataKeys removes X-Amz-Meta- prefix from minio internal
// encryption metadata that was sent by minio gateway
func CleanMinioInternalMetadataKeys(metadata map[string]string) map[string]string {
var newMeta = make(map[string]string, len(metadata))
for k, v := range metadata {
if strings.HasPrefix(k, "X-Amz-Meta-X-Minio-Internal-") {
newMeta[strings.TrimPrefix(k, "X-Amz-Meta-")] = v
} else {
newMeta[k] = v
}
}
return newMeta
}
// newS2CompressReader will read data from r, compress it and return the compressed data as a Reader.
// Use Close to ensure resources are released on incomplete streams.
//
// input 'on' is always recommended such that this function works
// properly, because we do not wish to create an object even if
// client closed the stream prematurely.
func newS2CompressReader(r io.Reader, on int64) io.ReadCloser {
pr, pw := io.Pipe()
comp := s2.NewWriter(pw)
// Copy input to compressor
go func() {
cn, err := io.Copy(comp, r)
if err != nil {
comp.Close()
pw.CloseWithError(err)
return
}
if on > 0 && on != cn {
// if client didn't sent all data
// from the client verify here.
comp.Close()
pw.CloseWithError(IncompleteBody{})
return
}
// Close the stream.
if err = comp.Close(); err != nil {
pw.CloseWithError(err)
return
}
// Everything ok, do regular close.
pw.Close()
}()
return pr
}
// compressSelfTest performs a self-test to ensure that compression
// algorithms completes a roundtrip. If any algorithm
// produces an incorrect checksum it fails with a hard error.
//
// compressSelfTest tries to catch any issue in the compression implementation
// early instead of silently corrupting data.
func compressSelfTest() {
// 4 MB block.
// Approx runtime ~30ms
data := make([]byte, 4<<20)
rng := rand.New(rand.NewSource(0))
for i := range data {
// Generate compressible stream...
data[i] = byte(rng.Int63() & 3)
}
failOnErr := func(err error) {
if err != nil {
logger.Fatal(errSelfTestFailure, "compress: error on self-test: %v", err)
}
}
const skip = 2<<20 + 511
r := newS2CompressReader(bytes.NewBuffer(data), int64(len(data)))
b, err := io.ReadAll(r)
failOnErr(err)
failOnErr(r.Close())
// Decompression reader.
s2Reader := s2.NewReader(bytes.NewBuffer(b))
// Apply the skipLen on the decompressed stream.
failOnErr(s2Reader.Skip(skip))
got, err := io.ReadAll(s2Reader)
failOnErr(err)
if !bytes.Equal(got, data[skip:]) {
logger.Fatal(errSelfTestFailure, "compress: self-test roundtrip mismatch.")
}
}