From 393f9e998b1b40aa59d3fb8794c3a73da38c3fb7 Mon Sep 17 00:00:00 2001 From: Wim Date: Sun, 24 May 2020 00:06:21 +0200 Subject: Update dependencies / vendor (#1146) --- .../ssh/internal/bcrypt_pbkdf/bcrypt_pbkdf.go | 93 ++++++++++++++++++++++ 1 file changed, 93 insertions(+) create mode 100644 vendor/golang.org/x/crypto/ssh/internal/bcrypt_pbkdf/bcrypt_pbkdf.go (limited to 'vendor/golang.org/x/crypto/ssh/internal') diff --git a/vendor/golang.org/x/crypto/ssh/internal/bcrypt_pbkdf/bcrypt_pbkdf.go b/vendor/golang.org/x/crypto/ssh/internal/bcrypt_pbkdf/bcrypt_pbkdf.go new file mode 100644 index 00000000..af81d266 --- /dev/null +++ b/vendor/golang.org/x/crypto/ssh/internal/bcrypt_pbkdf/bcrypt_pbkdf.go @@ -0,0 +1,93 @@ +// Copyright 2014 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. + +// Package bcrypt_pbkdf implements bcrypt_pbkdf(3) from OpenBSD. +// +// See https://flak.tedunangst.com/post/bcrypt-pbkdf and +// https://cvsweb.openbsd.org/cgi-bin/cvsweb/src/lib/libutil/bcrypt_pbkdf.c. +package bcrypt_pbkdf + +import ( + "crypto/sha512" + "errors" + "golang.org/x/crypto/blowfish" +) + +const blockSize = 32 + +// Key derives a key from the password, salt and rounds count, returning a +// []byte of length keyLen that can be used as cryptographic key. +func Key(password, salt []byte, rounds, keyLen int) ([]byte, error) { + if rounds < 1 { + return nil, errors.New("bcrypt_pbkdf: number of rounds is too small") + } + if len(password) == 0 { + return nil, errors.New("bcrypt_pbkdf: empty password") + } + if len(salt) == 0 || len(salt) > 1<<20 { + return nil, errors.New("bcrypt_pbkdf: bad salt length") + } + if keyLen > 1024 { + return nil, errors.New("bcrypt_pbkdf: keyLen is too large") + } + + numBlocks := (keyLen + blockSize - 1) / blockSize + key := make([]byte, numBlocks*blockSize) + + h := sha512.New() + h.Write(password) + shapass := h.Sum(nil) + + shasalt := make([]byte, 0, sha512.Size) + cnt, tmp := make([]byte, 4), make([]byte, blockSize) + for block := 1; block <= numBlocks; block++ { + h.Reset() + h.Write(salt) + cnt[0] = byte(block >> 24) + cnt[1] = byte(block >> 16) + cnt[2] = byte(block >> 8) + cnt[3] = byte(block) + h.Write(cnt) + bcryptHash(tmp, shapass, h.Sum(shasalt)) + + out := make([]byte, blockSize) + copy(out, tmp) + for i := 2; i <= rounds; i++ { + h.Reset() + h.Write(tmp) + bcryptHash(tmp, shapass, h.Sum(shasalt)) + for j := 0; j < len(out); j++ { + out[j] ^= tmp[j] + } + } + + for i, v := range out { + key[i*numBlocks+(block-1)] = v + } + } + return key[:keyLen], nil +} + +var magic = []byte("OxychromaticBlowfishSwatDynamite") + +func bcryptHash(out, shapass, shasalt []byte) { + c, err := blowfish.NewSaltedCipher(shapass, shasalt) + if err != nil { + panic(err) + } + for i := 0; i < 64; i++ { + blowfish.ExpandKey(shasalt, c) + blowfish.ExpandKey(shapass, c) + } + copy(out, magic) + for i := 0; i < 32; i += 8 { + for j := 0; j < 64; j++ { + c.Encrypt(out[i:i+8], out[i:i+8]) + } + } + // Swap bytes due to different endianness. + for i := 0; i < 32; i += 4 { + out[i+3], out[i+2], out[i+1], out[i] = out[i], out[i+1], out[i+2], out[i+3] + } +} -- cgit v1.2.3