minio/cmd/object-api-utils.go

272 lines
7.8 KiB
Go

/*
* Minio Cloud Storage, (C) 2015, 2016 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 (
"encoding/hex"
"fmt"
"path"
"runtime"
"strings"
"unicode/utf8"
"github.com/minio/minio/pkg/errors"
"github.com/skyrings/skyring-common/tools/uuid"
)
const (
// Minio meta bucket.
minioMetaBucket = ".minio.sys"
// Multipart meta prefix.
mpartMetaPrefix = "multipart"
// Minio Multipart meta prefix.
minioMetaMultipartBucket = minioMetaBucket + "/" + mpartMetaPrefix
// Minio Tmp meta prefix.
minioMetaTmpBucket = minioMetaBucket + "/tmp"
// DNS separator (period), used for bucket name validation.
dnsDelimiter = "."
)
// 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
}
// 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 "/".
func IsValidObjectName(object string) bool {
if len(object) == 0 {
return false
}
if hasSuffix(object, slashSeparator) || hasPrefix(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 len(object) > 1024 {
return false
}
if !utf8.ValidString(object) {
return false
}
// Reject unsupported characters in object name.
if strings.ContainsAny(object, "\\") {
return false
}
return true
}
// Slash separator.
const slashSeparator = "/"
// retainSlash - retains slash from a path.
func retainSlash(s string) string {
return strings.TrimSuffix(s, slashSeparator) + slashSeparator
}
// pathJoin - like path.Join() but retains trailing "/" of the last element
func pathJoin(elem ...string) string {
trailingSlash := ""
if len(elem) > 0 {
if hasSuffix(elem[len(elem)-1], slashSeparator) {
trailingSlash = "/"
}
}
return path.Join(elem...) + trailingSlash
}
// mustGetUUID - get a random UUID.
func mustGetUUID() string {
uuid, err := uuid.New()
if err != nil {
panic(fmt.Sprintf("Random UUID generation failed. Error: %s", err))
}
return uuid.String()
}
// Create an s3 compatible MD5sum for complete multipart transaction.
func getCompleteMultipartMD5(parts []CompletePart) (string, error) {
var finalMD5Bytes []byte
for _, part := range parts {
md5Bytes, err := hex.DecodeString(part.ETag)
if err != nil {
return "", errors.Trace(err)
}
finalMD5Bytes = append(finalMD5Bytes, md5Bytes...)
}
s3MD5 := fmt.Sprintf("%s-%d", getMD5Hash(finalMD5Bytes), len(parts))
return s3MD5, nil
}
// Clean meta etag keys 'md5Sum', 'etag'.
func cleanMetaETag(metadata map[string]string) map[string]string {
return cleanMetadata(metadata, "md5Sum", "etag")
}
// Clean metadata takes keys to be filtered
// and returns a new map with the keys filtered.
func cleanMetadata(metadata map[string]string, keyNames ...string) map[string]string {
var newMeta = make(map[string]string)
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
}
// 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)
}
// 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) bool {
bucketEntry = strings.TrimSuffix(bucketEntry, slashSeparator)
if !IsValidBucketName(bucketEntry) {
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
}
// byBucketName is a collection satisfying sort.Interface.
type byBucketName []BucketInfo
func (d byBucketName) Len() int { return len(d) }
func (d byBucketName) Swap(i, j int) { d[i], d[j] = d[j], d[i] }
func (d byBucketName) Less(i, j int) bool { return d[i].Name < d[j].Name }