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Diffstat (limited to 'vendor/golang.org/x/crypto/openpgp/packet/symmetric_key_encrypted.go')
-rw-r--r--vendor/golang.org/x/crypto/openpgp/packet/symmetric_key_encrypted.go155
1 files changed, 0 insertions, 155 deletions
diff --git a/vendor/golang.org/x/crypto/openpgp/packet/symmetric_key_encrypted.go b/vendor/golang.org/x/crypto/openpgp/packet/symmetric_key_encrypted.go
deleted file mode 100644
index 744c2d2..0000000
--- a/vendor/golang.org/x/crypto/openpgp/packet/symmetric_key_encrypted.go
+++ /dev/null
@@ -1,155 +0,0 @@
-// Copyright 2011 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 packet
-
-import (
- "bytes"
- "crypto/cipher"
- "io"
- "strconv"
-
- "golang.org/x/crypto/openpgp/errors"
- "golang.org/x/crypto/openpgp/s2k"
-)
-
-// This is the largest session key that we'll support. Since no 512-bit cipher
-// has even been seriously used, this is comfortably large.
-const maxSessionKeySizeInBytes = 64
-
-// SymmetricKeyEncrypted represents a passphrase protected session key. See RFC
-// 4880, section 5.3.
-type SymmetricKeyEncrypted struct {
- CipherFunc CipherFunction
- s2k func(out, in []byte)
- encryptedKey []byte
-}
-
-const symmetricKeyEncryptedVersion = 4
-
-func (ske *SymmetricKeyEncrypted) parse(r io.Reader) error {
- // RFC 4880, section 5.3.
- var buf [2]byte
- if _, err := readFull(r, buf[:]); err != nil {
- return err
- }
- if buf[0] != symmetricKeyEncryptedVersion {
- return errors.UnsupportedError("SymmetricKeyEncrypted version")
- }
- ske.CipherFunc = CipherFunction(buf[1])
-
- if ske.CipherFunc.KeySize() == 0 {
- return errors.UnsupportedError("unknown cipher: " + strconv.Itoa(int(buf[1])))
- }
-
- var err error
- ske.s2k, err = s2k.Parse(r)
- if err != nil {
- return err
- }
-
- encryptedKey := make([]byte, maxSessionKeySizeInBytes)
- // The session key may follow. We just have to try and read to find
- // out. If it exists then we limit it to maxSessionKeySizeInBytes.
- n, err := readFull(r, encryptedKey)
- if err != nil && err != io.ErrUnexpectedEOF {
- return err
- }
-
- if n != 0 {
- if n == maxSessionKeySizeInBytes {
- return errors.UnsupportedError("oversized encrypted session key")
- }
- ske.encryptedKey = encryptedKey[:n]
- }
-
- return nil
-}
-
-// Decrypt attempts to decrypt an encrypted session key and returns the key and
-// the cipher to use when decrypting a subsequent Symmetrically Encrypted Data
-// packet.
-func (ske *SymmetricKeyEncrypted) Decrypt(passphrase []byte) ([]byte, CipherFunction, error) {
- key := make([]byte, ske.CipherFunc.KeySize())
- ske.s2k(key, passphrase)
-
- if len(ske.encryptedKey) == 0 {
- return key, ske.CipherFunc, nil
- }
-
- // the IV is all zeros
- iv := make([]byte, ske.CipherFunc.blockSize())
- c := cipher.NewCFBDecrypter(ske.CipherFunc.new(key), iv)
- plaintextKey := make([]byte, len(ske.encryptedKey))
- c.XORKeyStream(plaintextKey, ske.encryptedKey)
- cipherFunc := CipherFunction(plaintextKey[0])
- if cipherFunc.blockSize() == 0 {
- return nil, ske.CipherFunc, errors.UnsupportedError("unknown cipher: " + strconv.Itoa(int(cipherFunc)))
- }
- plaintextKey = plaintextKey[1:]
- if l, cipherKeySize := len(plaintextKey), cipherFunc.KeySize(); l != cipherFunc.KeySize() {
- return nil, cipherFunc, errors.StructuralError("length of decrypted key (" + strconv.Itoa(l) + ") " +
- "not equal to cipher keysize (" + strconv.Itoa(cipherKeySize) + ")")
- }
- return plaintextKey, cipherFunc, nil
-}
-
-// SerializeSymmetricKeyEncrypted serializes a symmetric key packet to w. The
-// packet contains a random session key, encrypted by a key derived from the
-// given passphrase. The session key is returned and must be passed to
-// SerializeSymmetricallyEncrypted.
-// If config is nil, sensible defaults will be used.
-func SerializeSymmetricKeyEncrypted(w io.Writer, passphrase []byte, config *Config) (key []byte, err error) {
- cipherFunc := config.Cipher()
- keySize := cipherFunc.KeySize()
- if keySize == 0 {
- return nil, errors.UnsupportedError("unknown cipher: " + strconv.Itoa(int(cipherFunc)))
- }
-
- s2kBuf := new(bytes.Buffer)
- keyEncryptingKey := make([]byte, keySize)
- // s2k.Serialize salts and stretches the passphrase, and writes the
- // resulting key to keyEncryptingKey and the s2k descriptor to s2kBuf.
- err = s2k.Serialize(s2kBuf, keyEncryptingKey, config.Random(), passphrase, &s2k.Config{Hash: config.Hash(), S2KCount: config.PasswordHashIterations()})
- if err != nil {
- return
- }
- s2kBytes := s2kBuf.Bytes()
-
- packetLength := 2 /* header */ + len(s2kBytes) + 1 /* cipher type */ + keySize
- err = serializeHeader(w, packetTypeSymmetricKeyEncrypted, packetLength)
- if err != nil {
- return
- }
-
- var buf [2]byte
- buf[0] = symmetricKeyEncryptedVersion
- buf[1] = byte(cipherFunc)
- _, err = w.Write(buf[:])
- if err != nil {
- return
- }
- _, err = w.Write(s2kBytes)
- if err != nil {
- return
- }
-
- sessionKey := make([]byte, keySize)
- _, err = io.ReadFull(config.Random(), sessionKey)
- if err != nil {
- return
- }
- iv := make([]byte, cipherFunc.blockSize())
- c := cipher.NewCFBEncrypter(cipherFunc.new(keyEncryptingKey), iv)
- encryptedCipherAndKey := make([]byte, keySize+1)
- c.XORKeyStream(encryptedCipherAndKey, buf[1:])
- c.XORKeyStream(encryptedCipherAndKey[1:], sessionKey)
- _, err = w.Write(encryptedCipherAndKey)
- if err != nil {
- return
- }
-
- key = sessionKey
- return
-}