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authorDaniel J Walsh <dwalsh@redhat.com>2018-07-08 07:55:30 -0400
committerAtomic Bot <atomic-devel@projectatomic.io>2018-07-19 18:43:32 +0000
commit98703eb204923f06555605c648fc165a55214520 (patch)
treea407bae8b3489d4f9b0f0d0f228658bbfe95a38e /vendor/github.com/ulikunitz/xz/lzma/header.go
parentc020db8cd21cb221cfbe36b264e0ec02999596ed (diff)
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Vendor in latest code for storage,image, buildah
vendor in containers/storage vendor in containers/image vendor in projectatomic/buildah Signed-off-by: Daniel J Walsh <dwalsh@redhat.com> Closes: #1114 Approved by: mheon
Diffstat (limited to 'vendor/github.com/ulikunitz/xz/lzma/header.go')
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1 files changed, 167 insertions, 0 deletions
diff --git a/vendor/github.com/ulikunitz/xz/lzma/header.go b/vendor/github.com/ulikunitz/xz/lzma/header.go
new file mode 100644
index 000000000..bc708969f
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+++ b/vendor/github.com/ulikunitz/xz/lzma/header.go
@@ -0,0 +1,167 @@
+// Copyright 2014-2017 Ulrich Kunitz. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package lzma
+
+import (
+ "errors"
+ "fmt"
+)
+
+// uint32LE reads an uint32 integer from a byte slice
+func uint32LE(b []byte) uint32 {
+ x := uint32(b[3]) << 24
+ x |= uint32(b[2]) << 16
+ x |= uint32(b[1]) << 8
+ x |= uint32(b[0])
+ return x
+}
+
+// uint64LE converts the uint64 value stored as little endian to an uint64
+// value.
+func uint64LE(b []byte) uint64 {
+ x := uint64(b[7]) << 56
+ x |= uint64(b[6]) << 48
+ x |= uint64(b[5]) << 40
+ x |= uint64(b[4]) << 32
+ x |= uint64(b[3]) << 24
+ x |= uint64(b[2]) << 16
+ x |= uint64(b[1]) << 8
+ x |= uint64(b[0])
+ return x
+}
+
+// putUint32LE puts an uint32 integer into a byte slice that must have at least
+// a length of 4 bytes.
+func putUint32LE(b []byte, x uint32) {
+ b[0] = byte(x)
+ b[1] = byte(x >> 8)
+ b[2] = byte(x >> 16)
+ b[3] = byte(x >> 24)
+}
+
+// putUint64LE puts the uint64 value into the byte slice as little endian
+// value. The byte slice b must have at least place for 8 bytes.
+func putUint64LE(b []byte, x uint64) {
+ b[0] = byte(x)
+ b[1] = byte(x >> 8)
+ b[2] = byte(x >> 16)
+ b[3] = byte(x >> 24)
+ b[4] = byte(x >> 32)
+ b[5] = byte(x >> 40)
+ b[6] = byte(x >> 48)
+ b[7] = byte(x >> 56)
+}
+
+// noHeaderSize defines the value of the length field in the LZMA header.
+const noHeaderSize uint64 = 1<<64 - 1
+
+// HeaderLen provides the length of the LZMA file header.
+const HeaderLen = 13
+
+// header represents the header of an LZMA file.
+type header struct {
+ properties Properties
+ dictCap int
+ // uncompressed size; negative value if no size is given
+ size int64
+}
+
+// marshalBinary marshals the header.
+func (h *header) marshalBinary() (data []byte, err error) {
+ if err = h.properties.verify(); err != nil {
+ return nil, err
+ }
+ if !(0 <= h.dictCap && int64(h.dictCap) <= MaxDictCap) {
+ return nil, fmt.Errorf("lzma: DictCap %d out of range",
+ h.dictCap)
+ }
+
+ data = make([]byte, 13)
+
+ // property byte
+ data[0] = h.properties.Code()
+
+ // dictionary capacity
+ putUint32LE(data[1:5], uint32(h.dictCap))
+
+ // uncompressed size
+ var s uint64
+ if h.size > 0 {
+ s = uint64(h.size)
+ } else {
+ s = noHeaderSize
+ }
+ putUint64LE(data[5:], s)
+
+ return data, nil
+}
+
+// unmarshalBinary unmarshals the header.
+func (h *header) unmarshalBinary(data []byte) error {
+ if len(data) != HeaderLen {
+ return errors.New("lzma.unmarshalBinary: data has wrong length")
+ }
+
+ // properties
+ var err error
+ if h.properties, err = PropertiesForCode(data[0]); err != nil {
+ return err
+ }
+
+ // dictionary capacity
+ h.dictCap = int(uint32LE(data[1:]))
+ if h.dictCap < 0 {
+ return errors.New(
+ "LZMA header: dictionary capacity exceeds maximum " +
+ "integer")
+ }
+
+ // uncompressed size
+ s := uint64LE(data[5:])
+ if s == noHeaderSize {
+ h.size = -1
+ } else {
+ h.size = int64(s)
+ if h.size < 0 {
+ return errors.New(
+ "LZMA header: uncompressed size " +
+ "out of int64 range")
+ }
+ }
+
+ return nil
+}
+
+// validDictCap checks whether the dictionary capacity is correct. This
+// is used to weed out wrong file headers.
+func validDictCap(dictcap int) bool {
+ if int64(dictcap) == MaxDictCap {
+ return true
+ }
+ for n := uint(10); n < 32; n++ {
+ if dictcap == 1<<n {
+ return true
+ }
+ if dictcap == 1<<n+1<<(n-1) {
+ return true
+ }
+ }
+ return false
+}
+
+// ValidHeader checks for a valid LZMA file header. It allows only
+// dictionary sizes of 2^n or 2^n+2^(n-1) with n >= 10 or 2^32-1. If
+// there is an explicit size it must not exceed 256 GiB. The length of
+// the data argument must be HeaderLen.
+func ValidHeader(data []byte) bool {
+ var h header
+ if err := h.unmarshalBinary(data); err != nil {
+ return false
+ }
+ if !validDictCap(h.dictCap) {
+ return false
+ }
+ return h.size < 0 || h.size <= 1<<38
+}