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author | Daniel J Walsh <dwalsh@redhat.com> | 2018-07-08 07:55:30 -0400 |
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committer | Atomic Bot <atomic-devel@projectatomic.io> | 2018-07-19 18:43:32 +0000 |
commit | 98703eb204923f06555605c648fc165a55214520 (patch) | |
tree | a407bae8b3489d4f9b0f0d0f228658bbfe95a38e /vendor/github.com/ulikunitz/xz/lzma/header.go | |
parent | c020db8cd21cb221cfbe36b264e0ec02999596ed (diff) | |
download | podman-98703eb204923f06555605c648fc165a55214520.tar.gz podman-98703eb204923f06555605c648fc165a55214520.tar.bz2 podman-98703eb204923f06555605c648fc165a55214520.zip |
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')
-rw-r--r-- | vendor/github.com/ulikunitz/xz/lzma/header.go | 167 |
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 --- /dev/null +++ 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 +} |