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-rw-r--r--src/crypto/md5/gen.go259
1 files changed, 259 insertions, 0 deletions
diff --git a/src/crypto/md5/gen.go b/src/crypto/md5/gen.go
new file mode 100644
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+++ b/src/crypto/md5/gen.go
@@ -0,0 +1,259 @@
+// Copyright 2012 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.
+
+//go:build ignore
+
+// This program generates md5block.go
+// Invoke as
+//
+// go run gen.go -output md5block.go
+
+package main
+
+import (
+ "bytes"
+ "flag"
+ "go/format"
+ "log"
+ "os"
+ "strings"
+ "text/template"
+)
+
+var filename = flag.String("output", "md5block.go", "output file name")
+
+func main() {
+ flag.Parse()
+
+ var buf bytes.Buffer
+
+ t := template.Must(template.New("main").Funcs(funcs).Parse(program))
+ if err := t.Execute(&buf, data); err != nil {
+ log.Fatal(err)
+ }
+
+ data, err := format.Source(buf.Bytes())
+ if err != nil {
+ log.Fatal(err)
+ }
+ err = os.WriteFile(*filename, data, 0644)
+ if err != nil {
+ log.Fatal(err)
+ }
+}
+
+type Data struct {
+ a, b, c, d string
+ Shift1 []int
+ Shift2 []int
+ Shift3 []int
+ Shift4 []int
+ Table1 []uint32
+ Table2 []uint32
+ Table3 []uint32
+ Table4 []uint32
+}
+
+var funcs = template.FuncMap{
+ "dup": dup,
+ "relabel": relabel,
+ "rotate": rotate,
+ "idx": idx,
+ "seq": seq,
+}
+
+func dup(count int, x []int) []int {
+ var out []int
+ for i := 0; i < count; i++ {
+ out = append(out, x...)
+ }
+ return out
+}
+
+func relabel(s string) string {
+ return strings.NewReplacer("arg0", data.a, "arg1", data.b, "arg2", data.c, "arg3", data.d).Replace(s)
+}
+
+func rotate() string {
+ data.a, data.b, data.c, data.d = data.d, data.a, data.b, data.c
+ return "" // no output
+}
+
+func idx(round, index int) int {
+ v := 0
+ switch round {
+ case 1:
+ v = index
+ case 2:
+ v = (1 + 5*index) & 15
+ case 3:
+ v = (5 + 3*index) & 15
+ case 4:
+ v = (7 * index) & 15
+ }
+ return v
+}
+
+func seq(i int) []int {
+ s := make([]int, i)
+ for i := range s {
+ s[i] = i
+ }
+ return s
+}
+
+var data = Data{
+ a: "a",
+ b: "b",
+ c: "c",
+ d: "d",
+ Shift1: []int{7, 12, 17, 22},
+ Shift2: []int{5, 9, 14, 20},
+ Shift3: []int{4, 11, 16, 23},
+ Shift4: []int{6, 10, 15, 21},
+
+ // table[i] = int((1<<32) * abs(sin(i+1 radians))).
+ Table1: []uint32{
+ // round 1
+ 0xd76aa478,
+ 0xe8c7b756,
+ 0x242070db,
+ 0xc1bdceee,
+ 0xf57c0faf,
+ 0x4787c62a,
+ 0xa8304613,
+ 0xfd469501,
+ 0x698098d8,
+ 0x8b44f7af,
+ 0xffff5bb1,
+ 0x895cd7be,
+ 0x6b901122,
+ 0xfd987193,
+ 0xa679438e,
+ 0x49b40821,
+ },
+ Table2: []uint32{
+ // round 2
+ 0xf61e2562,
+ 0xc040b340,
+ 0x265e5a51,
+ 0xe9b6c7aa,
+ 0xd62f105d,
+ 0x2441453,
+ 0xd8a1e681,
+ 0xe7d3fbc8,
+ 0x21e1cde6,
+ 0xc33707d6,
+ 0xf4d50d87,
+ 0x455a14ed,
+ 0xa9e3e905,
+ 0xfcefa3f8,
+ 0x676f02d9,
+ 0x8d2a4c8a,
+ },
+ Table3: []uint32{
+ // round3
+ 0xfffa3942,
+ 0x8771f681,
+ 0x6d9d6122,
+ 0xfde5380c,
+ 0xa4beea44,
+ 0x4bdecfa9,
+ 0xf6bb4b60,
+ 0xbebfbc70,
+ 0x289b7ec6,
+ 0xeaa127fa,
+ 0xd4ef3085,
+ 0x4881d05,
+ 0xd9d4d039,
+ 0xe6db99e5,
+ 0x1fa27cf8,
+ 0xc4ac5665,
+ },
+ Table4: []uint32{
+ // round 4
+ 0xf4292244,
+ 0x432aff97,
+ 0xab9423a7,
+ 0xfc93a039,
+ 0x655b59c3,
+ 0x8f0ccc92,
+ 0xffeff47d,
+ 0x85845dd1,
+ 0x6fa87e4f,
+ 0xfe2ce6e0,
+ 0xa3014314,
+ 0x4e0811a1,
+ 0xf7537e82,
+ 0xbd3af235,
+ 0x2ad7d2bb,
+ 0xeb86d391,
+ },
+}
+
+var program = `// Copyright 2013 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.
+
+// Code generated by go run gen.go -output md5block.go; DO NOT EDIT.
+
+package md5
+
+import (
+ "encoding/binary"
+ "math/bits"
+)
+
+func blockGeneric(dig *digest, p []byte) {
+ // load state
+ a, b, c, d := dig.s[0], dig.s[1], dig.s[2], dig.s[3]
+
+ for i := 0; i <= len(p)-BlockSize; i += BlockSize {
+ // eliminate bounds checks on p
+ q := p[i:]
+ q = q[:BlockSize:BlockSize]
+
+ // save current state
+ aa, bb, cc, dd := a, b, c, d
+
+ // load input block
+ {{range $i := seq 16 -}}
+ {{printf "x%x := binary.LittleEndian.Uint32(q[4*%#x:])" $i $i}}
+ {{end}}
+
+ // round 1
+ {{range $i, $s := dup 4 .Shift1 -}}
+ {{printf "arg0 = arg1 + bits.RotateLeft32((((arg2^arg3)&arg1)^arg3)+arg0+x%x+%#08x, %d)" (idx 1 $i) (index $.Table1 $i) $s | relabel}}
+ {{rotate -}}
+ {{end}}
+
+ // round 2
+ {{range $i, $s := dup 4 .Shift2 -}}
+ {{printf "arg0 = arg1 + bits.RotateLeft32((((arg1^arg2)&arg3)^arg2)+arg0+x%x+%#08x, %d)" (idx 2 $i) (index $.Table2 $i) $s | relabel}}
+ {{rotate -}}
+ {{end}}
+
+ // round 3
+ {{range $i, $s := dup 4 .Shift3 -}}
+ {{printf "arg0 = arg1 + bits.RotateLeft32((arg1^arg2^arg3)+arg0+x%x+%#08x, %d)" (idx 3 $i) (index $.Table3 $i) $s | relabel}}
+ {{rotate -}}
+ {{end}}
+
+ // round 4
+ {{range $i, $s := dup 4 .Shift4 -}}
+ {{printf "arg0 = arg1 + bits.RotateLeft32((arg2^(arg1|^arg3))+arg0+x%x+%#08x, %d)" (idx 4 $i) (index $.Table4 $i) $s | relabel}}
+ {{rotate -}}
+ {{end}}
+
+ // add saved state
+ a += aa
+ b += bb
+ c += cc
+ d += dd
+ }
+
+ // save state
+ dig.s[0], dig.s[1], dig.s[2], dig.s[3] = a, b, c, d
+}
+`