ChecksumIncludesMultipart

	// ChecksumNone indicates no checksum.
	ChecksumNone ChecksumType = 0
)

// Checksum is a type and base 64 encoded value.
type Checksum struct {
	Type    ChecksumType
	Encoded string
	Raw     []byte
}

// Is returns if c is all of t.
func (c ChecksumType) Is(t ChecksumType) bool {
	if t == ChecksumNone {
		return c == ChecksumNone
	}

	// MD5 checksum.
	ErrMissingCustomerKeyMD5 = Errorf("The SSE-C request is missing the customer key MD5")

	// ErrInvalidCustomerKey indicates that the SSE-C client key is not valid - e.g. not a
	// base64-encoded string or not 256 bits long.
	ErrInvalidCustomerKey = Errorf("The SSE-C client key is invalid")

	// ErrSecretKeyMismatch indicates that the provided secret key (SSE-C client key / SSE-S3 KMS key)

	return d, nil
}

// configReader returns a PutObjReader and ObjectOptions needed to save config
// using a PutObject API. PutObjReader encrypts json encoded tier configurations
// if KMS is enabled, otherwise simply yields the json encoded bytes as is.
// Similarly, ObjectOptions value depends on KMS' status.
func (config *TierConfigMgr) configReader(ctx context.Context) (*PutObjReader, *ObjectOptions, error) {

)

// getDataBlockLen - get length of data blocks from encoded blocks.
func getDataBlockLen(enBlocks [][]byte, dataBlocks int) int {
	size := 0
	// Figure out the data block length.
	for _, block := range enBlocks[:dataBlocks] {
		size += len(block)
	}
	return size
}

// Writes all the data blocks from encoded blocks until requested
// outSize length. Provides a way to skip bytes until the offset.

//
// returns ErrNone if matches. S3 errors otherwise.
func doesPresignV2SignatureMatch(r *http.Request) APIErrorCode {
	// r.RequestURI will have raw encoded URI as sent by the client.
	tokens := strings.SplitN(r.RequestURI, "?", 2)
	encodedResource := tokens[0]
	encodedQuery := ""
	if len(tokens) == 2 {
		encodedQuery = tokens[1]
	}

	var (

		gotv := got.Cache[wkey]
		if !equalAsJSON(gotv, wval) {
			t.Errorf("deserialize mismatch, key %v\nwant: %#v\ngot:  %#v", wkey, wval, gotv)
		}
	}
}

// equalAsJSON returns whether the values are equal when encoded as JSON.
func equalAsJSON(a, b interface{}) bool {
	aj, err := json.Marshal(a)
	if err != nil {
		panic(err)
	}
	bj, err := json.Marshal(b)
	if err != nil {
		panic(err)
	}

	}

	// Check if a session policy is set. If so, decode it here.
	sp, spok := claims.Lookup(policy.SessionPolicyName)
	if spok {
		// Looks like subpolicy is set and is a string, if set then its
		// base64 encoded, decode it. Decoding fails reject such
		// requests.
		spBytes, err := base64.StdEncoding.DecodeString(sp)
		if err != nil {
			// Base64 decoding fails, we should log to indicate

		return key, err
	}
	err = key.Unseal(unsealKey, sealedKey, s3.String(), bucket, object)
	return key, err
}

// CreateMetadata encodes the sealed object key into the metadata and returns
// the modified metadata. If the keyID and the kmsKey is not empty it encodes
// both into the metadata as well. It allocates a new metadata map if metadata
// is nil.

		}
		if b == ';' { // separating character
			break
		}

		// Manually deserialize the size since AWS specified
		// the chunk size to be of variable width. In particular,
		// a size of 16 is encoded as `10` while a size of 64 KB
		// is `10000`.
		switch {
		case b >= '0' && b <= '9':
			size = size<<4 | int(b-'0')
		case b >= 'a' && b <= 'f':
			size = size<<4 | int(b-('a'-10))

				ok = false
				continue
			}
			// Delete first shard and reconstruct...
			first := encoded[0]
			encoded[0] = nil
			failOnErr(e.DecodeDataBlocks(encoded))
			if a, b := first, encoded[0]; !bytes.Equal(a, b) {
				fmt.Fprintf(os.Stderr, "%v: error on self-test [d:%d,p:%d]: want %#v, got %#v\n", algo, conf[0], conf[1], hex.EncodeToString(a), hex.EncodeToString(b))