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-rw-r--r--src/pkg/syscall/unzip_nacl.go685
1 files changed, 685 insertions, 0 deletions
diff --git a/src/pkg/syscall/unzip_nacl.go b/src/pkg/syscall/unzip_nacl.go
new file mode 100644
index 000000000..5845e44f0
--- /dev/null
+++ b/src/pkg/syscall/unzip_nacl.go
@@ -0,0 +1,685 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Small in-memory unzip implementation.
+// A simplified copy of the pre-Go 1 compress/flate/inflate.go
+// and a modified copy of the zip reader in package time.
+// (The one in package time does not support decompression; this one does.)
+
+package syscall
+
+const (
+ maxCodeLen = 16 // max length of Huffman code
+ maxHist = 32768 // max history required
+ maxLit = 286
+ maxDist = 32
+ numCodes = 19 // number of codes in Huffman meta-code
+)
+
+type decompressor struct {
+ in string // compressed input
+ out []byte // uncompressed output
+ b uint32 // input bits, at top of b
+ nb uint
+ err bool // invalid input
+ eof bool // reached EOF
+
+ h1, h2 huffmanDecoder // decoders for literal/length, distance
+ bits [maxLit + maxDist]int // lengths defining Huffman codes
+ codebits [numCodes]int
+}
+
+func (f *decompressor) nextBlock() {
+ for f.nb < 1+2 {
+ if f.moreBits(); f.err {
+ return
+ }
+ }
+ f.eof = f.b&1 == 1
+ f.b >>= 1
+ typ := f.b & 3
+ f.b >>= 2
+ f.nb -= 1 + 2
+ switch typ {
+ case 0:
+ f.dataBlock()
+ case 1:
+ // compressed, fixed Huffman tables
+ f.huffmanBlock(&fixedHuffmanDecoder, nil)
+ case 2:
+ // compressed, dynamic Huffman tables
+ if f.readHuffman(); f.err {
+ break
+ }
+ f.huffmanBlock(&f.h1, &f.h2)
+ default:
+ // 3 is reserved.
+ f.err = true
+ }
+}
+
+// RFC 1951 section 3.2.7.
+// Compression with dynamic Huffman codes
+
+var codeOrder = [...]int{16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15}
+
+func (f *decompressor) readHuffman() {
+ // HLIT[5], HDIST[5], HCLEN[4].
+ for f.nb < 5+5+4 {
+ if f.moreBits(); f.err {
+ return
+ }
+ }
+ nlit := int(f.b&0x1F) + 257
+ f.b >>= 5
+ ndist := int(f.b&0x1F) + 1
+ f.b >>= 5
+ nclen := int(f.b&0xF) + 4
+ f.b >>= 4
+ f.nb -= 5 + 5 + 4
+
+ // (HCLEN+4)*3 bits: code lengths in the magic codeOrder order.
+ for i := 0; i < nclen; i++ {
+ for f.nb < 3 {
+ if f.moreBits(); f.err {
+ return
+ }
+ }
+ f.codebits[codeOrder[i]] = int(f.b & 0x7)
+ f.b >>= 3
+ f.nb -= 3
+ }
+ for i := nclen; i < len(codeOrder); i++ {
+ f.codebits[codeOrder[i]] = 0
+ }
+ if !f.h1.init(f.codebits[0:]) {
+ f.err = true
+ return
+ }
+
+ // HLIT + 257 code lengths, HDIST + 1 code lengths,
+ // using the code length Huffman code.
+ for i, n := 0, nlit+ndist; i < n; {
+ x := f.huffSym(&f.h1)
+ if f.err {
+ return
+ }
+ if x < 16 {
+ // Actual length.
+ f.bits[i] = x
+ i++
+ continue
+ }
+ // Repeat previous length or zero.
+ var rep int
+ var nb uint
+ var b int
+ switch x {
+ default:
+ f.err = true
+ return
+ case 16:
+ rep = 3
+ nb = 2
+ if i == 0 {
+ f.err = true
+ return
+ }
+ b = f.bits[i-1]
+ case 17:
+ rep = 3
+ nb = 3
+ b = 0
+ case 18:
+ rep = 11
+ nb = 7
+ b = 0
+ }
+ for f.nb < nb {
+ if f.moreBits(); f.err {
+ return
+ }
+ }
+ rep += int(f.b & uint32(1<<nb-1))
+ f.b >>= nb
+ f.nb -= nb
+ if i+rep > n {
+ f.err = true
+ return
+ }
+ for j := 0; j < rep; j++ {
+ f.bits[i] = b
+ i++
+ }
+ }
+
+ if !f.h1.init(f.bits[0:nlit]) || !f.h2.init(f.bits[nlit:nlit+ndist]) {
+ f.err = true
+ return
+ }
+}
+
+// Decode a single Huffman block from f.
+// hl and hd are the Huffman states for the lit/length values
+// and the distance values, respectively. If hd == nil, using the
+// fixed distance encoding associated with fixed Huffman blocks.
+func (f *decompressor) huffmanBlock(hl, hd *huffmanDecoder) {
+ for {
+ v := f.huffSym(hl)
+ if f.err {
+ return
+ }
+ var n uint // number of bits extra
+ var length int
+ switch {
+ case v < 256:
+ f.out = append(f.out, byte(v))
+ continue
+ case v == 256:
+ // Done with huffman block; read next block.
+ return
+ // otherwise, reference to older data
+ case v < 265:
+ length = v - (257 - 3)
+ n = 0
+ case v < 269:
+ length = v*2 - (265*2 - 11)
+ n = 1
+ case v < 273:
+ length = v*4 - (269*4 - 19)
+ n = 2
+ case v < 277:
+ length = v*8 - (273*8 - 35)
+ n = 3
+ case v < 281:
+ length = v*16 - (277*16 - 67)
+ n = 4
+ case v < 285:
+ length = v*32 - (281*32 - 131)
+ n = 5
+ default:
+ length = 258
+ n = 0
+ }
+ if n > 0 {
+ for f.nb < n {
+ if f.moreBits(); f.err {
+ return
+ }
+ }
+ length += int(f.b & uint32(1<<n-1))
+ f.b >>= n
+ f.nb -= n
+ }
+
+ var dist int
+ if hd == nil {
+ for f.nb < 5 {
+ if f.moreBits(); f.err {
+ return
+ }
+ }
+ dist = int(reverseByte[(f.b&0x1F)<<3])
+ f.b >>= 5
+ f.nb -= 5
+ } else {
+ if dist = f.huffSym(hd); f.err {
+ return
+ }
+ }
+
+ switch {
+ case dist < 4:
+ dist++
+ case dist >= 30:
+ f.err = true
+ return
+ default:
+ nb := uint(dist-2) >> 1
+ // have 1 bit in bottom of dist, need nb more.
+ extra := (dist & 1) << nb
+ for f.nb < nb {
+ if f.moreBits(); f.err {
+ return
+ }
+ }
+ extra |= int(f.b & uint32(1<<nb-1))
+ f.b >>= nb
+ f.nb -= nb
+ dist = 1<<(nb+1) + 1 + extra
+ }
+
+ // Copy [-dist:-dist+length] into output.
+ // Encoding can be prescient, so no check on length.
+ if dist > len(f.out) {
+ f.err = true
+ return
+ }
+
+ p := len(f.out) - dist
+ for i := 0; i < length; i++ {
+ f.out = append(f.out, f.out[p])
+ p++
+ }
+ }
+}
+
+// Copy a single uncompressed data block from input to output.
+func (f *decompressor) dataBlock() {
+ // Uncompressed.
+ // Discard current half-byte.
+ f.nb = 0
+ f.b = 0
+
+ if len(f.in) < 4 {
+ f.err = true
+ return
+ }
+
+ buf := f.in[:4]
+ f.in = f.in[4:]
+ n := int(buf[0]) | int(buf[1])<<8
+ nn := int(buf[2]) | int(buf[3])<<8
+ if uint16(nn) != uint16(^n) {
+ f.err = true
+ return
+ }
+
+ if len(f.in) < n {
+ f.err = true
+ return
+ }
+ f.out = append(f.out, f.in[:n]...)
+ f.in = f.in[n:]
+}
+
+func (f *decompressor) moreBits() {
+ if len(f.in) == 0 {
+ f.err = true
+ return
+ }
+ c := f.in[0]
+ f.in = f.in[1:]
+ f.b |= uint32(c) << f.nb
+ f.nb += 8
+}
+
+// Read the next Huffman-encoded symbol from f according to h.
+func (f *decompressor) huffSym(h *huffmanDecoder) int {
+ for n := uint(h.min); n <= uint(h.max); n++ {
+ lim := h.limit[n]
+ if lim == -1 {
+ continue
+ }
+ for f.nb < n {
+ if f.moreBits(); f.err {
+ return 0
+ }
+ }
+ v := int(f.b & uint32(1<<n-1))
+ v <<= 16 - n
+ v = int(reverseByte[v>>8]) | int(reverseByte[v&0xFF])<<8 // reverse bits
+ if v <= lim {
+ f.b >>= n
+ f.nb -= n
+ return h.codes[v-h.base[n]]
+ }
+ }
+ f.err = true
+ return 0
+}
+
+var reverseByte = [256]byte{
+ 0x00, 0x80, 0x40, 0xc0, 0x20, 0xa0, 0x60, 0xe0,
+ 0x10, 0x90, 0x50, 0xd0, 0x30, 0xb0, 0x70, 0xf0,
+ 0x08, 0x88, 0x48, 0xc8, 0x28, 0xa8, 0x68, 0xe8,
+ 0x18, 0x98, 0x58, 0xd8, 0x38, 0xb8, 0x78, 0xf8,
+ 0x04, 0x84, 0x44, 0xc4, 0x24, 0xa4, 0x64, 0xe4,
+ 0x14, 0x94, 0x54, 0xd4, 0x34, 0xb4, 0x74, 0xf4,
+ 0x0c, 0x8c, 0x4c, 0xcc, 0x2c, 0xac, 0x6c, 0xec,
+ 0x1c, 0x9c, 0x5c, 0xdc, 0x3c, 0xbc, 0x7c, 0xfc,
+ 0x02, 0x82, 0x42, 0xc2, 0x22, 0xa2, 0x62, 0xe2,
+ 0x12, 0x92, 0x52, 0xd2, 0x32, 0xb2, 0x72, 0xf2,
+ 0x0a, 0x8a, 0x4a, 0xca, 0x2a, 0xaa, 0x6a, 0xea,
+ 0x1a, 0x9a, 0x5a, 0xda, 0x3a, 0xba, 0x7a, 0xfa,
+ 0x06, 0x86, 0x46, 0xc6, 0x26, 0xa6, 0x66, 0xe6,
+ 0x16, 0x96, 0x56, 0xd6, 0x36, 0xb6, 0x76, 0xf6,
+ 0x0e, 0x8e, 0x4e, 0xce, 0x2e, 0xae, 0x6e, 0xee,
+ 0x1e, 0x9e, 0x5e, 0xde, 0x3e, 0xbe, 0x7e, 0xfe,
+ 0x01, 0x81, 0x41, 0xc1, 0x21, 0xa1, 0x61, 0xe1,
+ 0x11, 0x91, 0x51, 0xd1, 0x31, 0xb1, 0x71, 0xf1,
+ 0x09, 0x89, 0x49, 0xc9, 0x29, 0xa9, 0x69, 0xe9,
+ 0x19, 0x99, 0x59, 0xd9, 0x39, 0xb9, 0x79, 0xf9,
+ 0x05, 0x85, 0x45, 0xc5, 0x25, 0xa5, 0x65, 0xe5,
+ 0x15, 0x95, 0x55, 0xd5, 0x35, 0xb5, 0x75, 0xf5,
+ 0x0d, 0x8d, 0x4d, 0xcd, 0x2d, 0xad, 0x6d, 0xed,
+ 0x1d, 0x9d, 0x5d, 0xdd, 0x3d, 0xbd, 0x7d, 0xfd,
+ 0x03, 0x83, 0x43, 0xc3, 0x23, 0xa3, 0x63, 0xe3,
+ 0x13, 0x93, 0x53, 0xd3, 0x33, 0xb3, 0x73, 0xf3,
+ 0x0b, 0x8b, 0x4b, 0xcb, 0x2b, 0xab, 0x6b, 0xeb,
+ 0x1b, 0x9b, 0x5b, 0xdb, 0x3b, 0xbb, 0x7b, 0xfb,
+ 0x07, 0x87, 0x47, 0xc7, 0x27, 0xa7, 0x67, 0xe7,
+ 0x17, 0x97, 0x57, 0xd7, 0x37, 0xb7, 0x77, 0xf7,
+ 0x0f, 0x8f, 0x4f, 0xcf, 0x2f, 0xaf, 0x6f, 0xef,
+ 0x1f, 0x9f, 0x5f, 0xdf, 0x3f, 0xbf, 0x7f, 0xff,
+}
+
+// Hard-coded Huffman tables for DEFLATE algorithm.
+// See RFC 1951, section 3.2.6.
+var fixedHuffmanDecoder = huffmanDecoder{
+ 7, 9,
+ [maxCodeLen + 1]int{7: 23, 199, 511},
+ [maxCodeLen + 1]int{7: 0, 24, 224},
+ []int{
+ // length 7: 256-279
+ 256, 257, 258, 259, 260, 261, 262,
+ 263, 264, 265, 266, 267, 268, 269,
+ 270, 271, 272, 273, 274, 275, 276,
+ 277, 278, 279,
+
+ // length 8: 0-143
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11,
+ 12, 13, 14, 15, 16, 17, 18, 19, 20, 21,
+ 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
+ 32, 33, 34, 35, 36, 37, 38, 39, 40, 41,
+ 42, 43, 44, 45, 46, 47, 48, 49, 50, 51,
+ 52, 53, 54, 55, 56, 57, 58, 59, 60, 61,
+ 62, 63, 64, 65, 66, 67, 68, 69, 70, 71,
+ 72, 73, 74, 75, 76, 77, 78, 79, 80, 81,
+ 82, 83, 84, 85, 86, 87, 88, 89, 90, 91,
+ 92, 93, 94, 95, 96, 97, 98, 99, 100,
+ 101, 102, 103, 104, 105, 106, 107, 108,
+ 109, 110, 111, 112, 113, 114, 115, 116,
+ 117, 118, 119, 120, 121, 122, 123, 124,
+ 125, 126, 127, 128, 129, 130, 131, 132,
+ 133, 134, 135, 136, 137, 138, 139, 140,
+ 141, 142, 143,
+
+ // length 8: 280-287
+ 280, 281, 282, 283, 284, 285, 286, 287,
+
+ // length 9: 144-255
+ 144, 145, 146, 147, 148, 149, 150, 151,
+ 152, 153, 154, 155, 156, 157, 158, 159,
+ 160, 161, 162, 163, 164, 165, 166, 167,
+ 168, 169, 170, 171, 172, 173, 174, 175,
+ 176, 177, 178, 179, 180, 181, 182, 183,
+ 184, 185, 186, 187, 188, 189, 190, 191,
+ 192, 193, 194, 195, 196, 197, 198, 199,
+ 200, 201, 202, 203, 204, 205, 206, 207,
+ 208, 209, 210, 211, 212, 213, 214, 215,
+ 216, 217, 218, 219, 220, 221, 222, 223,
+ 224, 225, 226, 227, 228, 229, 230, 231,
+ 232, 233, 234, 235, 236, 237, 238, 239,
+ 240, 241, 242, 243, 244, 245, 246, 247,
+ 248, 249, 250, 251, 252, 253, 254, 255,
+ },
+}
+
+// Huffman decoder is based on
+// J. Brian Connell, ``A Huffman-Shannon-Fano Code,''
+// Proceedings of the IEEE, 61(7) (July 1973), pp 1046-1047.
+type huffmanDecoder struct {
+ // min, max code length
+ min, max int
+
+ // limit[i] = largest code word of length i
+ // Given code v of length n,
+ // need more bits if v > limit[n].
+ limit [maxCodeLen + 1]int
+
+ // base[i] = smallest code word of length i - seq number
+ base [maxCodeLen + 1]int
+
+ // codes[seq number] = output code.
+ // Given code v of length n, value is
+ // codes[v - base[n]].
+ codes []int
+}
+
+// Initialize Huffman decoding tables from array of code lengths.
+func (h *huffmanDecoder) init(bits []int) bool {
+ // Count number of codes of each length,
+ // compute min and max length.
+ var count [maxCodeLen + 1]int
+ var min, max int
+ for _, n := range bits {
+ if n == 0 {
+ continue
+ }
+ if min == 0 || n < min {
+ min = n
+ }
+ if n > max {
+ max = n
+ }
+ count[n]++
+ }
+ if max == 0 {
+ return false
+ }
+
+ h.min = min
+ h.max = max
+
+ // For each code range, compute
+ // nextcode (first code of that length),
+ // limit (last code of that length), and
+ // base (offset from first code to sequence number).
+ code := 0
+ seq := 0
+ var nextcode [maxCodeLen]int
+ for i := min; i <= max; i++ {
+ n := count[i]
+ nextcode[i] = code
+ h.base[i] = code - seq
+ code += n
+ seq += n
+ h.limit[i] = code - 1
+ code <<= 1
+ }
+
+ // Make array mapping sequence numbers to codes.
+ if len(h.codes) < len(bits) {
+ h.codes = make([]int, len(bits))
+ }
+ for i, n := range bits {
+ if n == 0 {
+ continue
+ }
+ code := nextcode[n]
+ nextcode[n]++
+ seq := code - h.base[n]
+ h.codes[seq] = i
+ }
+ return true
+}
+
+func inflate(in string) (out []byte) {
+ var d decompressor
+ d.in = in
+ for !d.err && !d.eof {
+ d.nextBlock()
+ }
+ if len(d.in) != 0 {
+ println("fs unzip: junk at end of compressed data")
+ return nil
+ }
+ return d.out
+}
+
+// get4 returns the little-endian 32-bit value in b.
+func zget4(b string) int {
+ if len(b) < 4 {
+ return 0
+ }
+ return int(b[0]) | int(b[1])<<8 | int(b[2])<<16 | int(b[3])<<24
+}
+
+// get2 returns the little-endian 16-bit value in b.
+func zget2(b string) int {
+ if len(b) < 2 {
+ return 0
+ }
+ return int(b[0]) | int(b[1])<<8
+}
+
+func unzip(data string) {
+ const (
+ zecheader = 0x06054b50
+ zcheader = 0x02014b50
+ ztailsize = 22
+ zheadersize = 30
+ zheader = 0x04034b50
+ )
+
+ buf := data[len(data)-ztailsize:]
+ n := zget2(buf[10:])
+ size := zget4(buf[12:])
+ off := zget4(buf[16:])
+
+ hdr := data[off : off+size]
+ for i := 0; i < n; i++ {
+ // zip entry layout:
+ // 0 magic[4]
+ // 4 madevers[1]
+ // 5 madeos[1]
+ // 6 extvers[1]
+ // 7 extos[1]
+ // 8 flags[2]
+ // 10 meth[2]
+ // 12 modtime[2]
+ // 14 moddate[2]
+ // 16 crc[4]
+ // 20 csize[4]
+ // 24 uncsize[4]
+ // 28 namelen[2]
+ // 30 xlen[2]
+ // 32 fclen[2]
+ // 34 disknum[2]
+ // 36 iattr[2]
+ // 38 eattr[4]
+ // 42 off[4]
+ // 46 name[namelen]
+ // 46+namelen+xlen+fclen - next header
+ //
+ if zget4(hdr) != zcheader {
+ println("fs unzip: bad magic")
+ break
+ }
+ meth := zget2(hdr[10:])
+ mtime := zget2(hdr[12:])
+ mdate := zget2(hdr[14:])
+ csize := zget4(hdr[20:])
+ size := zget4(hdr[24:])
+ namelen := zget2(hdr[28:])
+ xlen := zget2(hdr[30:])
+ fclen := zget2(hdr[32:])
+ xattr := uint32(zget4(hdr[38:])) >> 16
+ off := zget4(hdr[42:])
+ name := hdr[46 : 46+namelen]
+ hdr = hdr[46+namelen+xlen+fclen:]
+
+ // zip per-file header layout:
+ // 0 magic[4]
+ // 4 extvers[1]
+ // 5 extos[1]
+ // 6 flags[2]
+ // 8 meth[2]
+ // 10 modtime[2]
+ // 12 moddate[2]
+ // 14 crc[4]
+ // 18 csize[4]
+ // 22 uncsize[4]
+ // 26 namelen[2]
+ // 28 xlen[2]
+ // 30 name[namelen]
+ // 30+namelen+xlen - file data
+ //
+ buf := data[off : off+zheadersize+namelen]
+ if zget4(buf) != zheader ||
+ zget2(buf[8:]) != meth ||
+ zget2(buf[26:]) != namelen ||
+ buf[30:30+namelen] != name {
+ println("fs unzip: inconsistent zip file")
+ return
+ }
+ xlen = zget2(buf[28:])
+
+ off += zheadersize + namelen + xlen
+
+ var fdata []byte
+ switch meth {
+ case 0:
+ // buf is uncompressed
+ buf = data[off : off+size]
+ fdata = []byte(buf)
+ case 8:
+ // buf is deflate-compressed
+ buf = data[off : off+csize]
+ fdata = inflate(buf)
+ if len(fdata) != size {
+ println("fs unzip: inconsistent size in zip file")
+ return
+ }
+ }
+
+ if xattr&S_IFMT == 0 {
+ if xattr&0777 == 0 {
+ xattr |= 0666
+ }
+ if len(name) > 0 && name[len(name)-1] == '/' {
+ xattr |= S_IFDIR
+ xattr |= 0111
+ } else {
+ xattr |= S_IFREG
+ }
+ }
+
+ if err := create(name, xattr, zipToTime(mdate, mtime), fdata); err != nil {
+ print("fs unzip: create ", name, ": ", err.Error(), "\n")
+ }
+ }
+
+ chdirEnv()
+}
+
+func zipToTime(date, time int) int64 {
+ dd := date & 0x1f
+ mm := date >> 5 & 0xf
+ yy := date >> 9 // since 1980
+
+ sec := int64(315532800) // jan 1 1980
+ sec += int64(yy) * 365 * 86400
+ sec += int64(yy) / 4 * 86400
+ if yy%4 > 0 || mm >= 3 {
+ sec += 86400
+ }
+ sec += int64(daysBeforeMonth[mm]) * 86400
+ sec += int64(dd-1) * 86400
+
+ h := time >> 11
+ m := time >> 5 & 0x3F
+ s := time & 0x1f * 2
+ sec += int64(h*3600 + m*60 + s)
+
+ return sec
+}
+
+var daysBeforeMonth = [...]int32{
+ 0,
+ 0,
+ 31,
+ 31 + 28,
+ 31 + 28 + 31,
+ 31 + 28 + 31 + 30,
+ 31 + 28 + 31 + 30 + 31,
+ 31 + 28 + 31 + 30 + 31 + 30,
+ 31 + 28 + 31 + 30 + 31 + 30 + 31,
+ 31 + 28 + 31 + 30 + 31 + 30 + 31 + 31,
+ 31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30,
+ 31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31,
+ 31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31 + 30,
+ 31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31 + 30 + 31,
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-17 07:34:02 +0000