X-Git-Url: https://git.immae.eu/?a=blobdiff_plain;f=vendor%2Fgolang.org%2Fx%2Fcrypto%2Fopenpgp%2Fwrite.go;fp=vendor%2Fgolang.org%2Fx%2Fcrypto%2Fopenpgp%2Fwrite.go;h=65a304cc8679662991f1e865a97bf7976f62410f;hb=c680a8e1622ed0f18751d9d167c836ee24f5e897;hp=0000000000000000000000000000000000000000;hpb=38f8880ac81bfabc6d7f82e4dc89661f20fc559e;p=github%2Ffretlink%2Fterraform-provider-statuscake.git diff --git a/vendor/golang.org/x/crypto/openpgp/write.go b/vendor/golang.org/x/crypto/openpgp/write.go new file mode 100644 index 0000000..65a304c --- /dev/null +++ b/vendor/golang.org/x/crypto/openpgp/write.go @@ -0,0 +1,378 @@ +// 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 openpgp + +import ( + "crypto" + "hash" + "io" + "strconv" + "time" + + "golang.org/x/crypto/openpgp/armor" + "golang.org/x/crypto/openpgp/errors" + "golang.org/x/crypto/openpgp/packet" + "golang.org/x/crypto/openpgp/s2k" +) + +// DetachSign signs message with the private key from signer (which must +// already have been decrypted) and writes the signature to w. +// If config is nil, sensible defaults will be used. +func DetachSign(w io.Writer, signer *Entity, message io.Reader, config *packet.Config) error { + return detachSign(w, signer, message, packet.SigTypeBinary, config) +} + +// ArmoredDetachSign signs message with the private key from signer (which +// must already have been decrypted) and writes an armored signature to w. +// If config is nil, sensible defaults will be used. +func ArmoredDetachSign(w io.Writer, signer *Entity, message io.Reader, config *packet.Config) (err error) { + return armoredDetachSign(w, signer, message, packet.SigTypeBinary, config) +} + +// DetachSignText signs message (after canonicalising the line endings) with +// the private key from signer (which must already have been decrypted) and +// writes the signature to w. +// If config is nil, sensible defaults will be used. +func DetachSignText(w io.Writer, signer *Entity, message io.Reader, config *packet.Config) error { + return detachSign(w, signer, message, packet.SigTypeText, config) +} + +// ArmoredDetachSignText signs message (after canonicalising the line endings) +// with the private key from signer (which must already have been decrypted) +// and writes an armored signature to w. +// If config is nil, sensible defaults will be used. +func ArmoredDetachSignText(w io.Writer, signer *Entity, message io.Reader, config *packet.Config) error { + return armoredDetachSign(w, signer, message, packet.SigTypeText, config) +} + +func armoredDetachSign(w io.Writer, signer *Entity, message io.Reader, sigType packet.SignatureType, config *packet.Config) (err error) { + out, err := armor.Encode(w, SignatureType, nil) + if err != nil { + return + } + err = detachSign(out, signer, message, sigType, config) + if err != nil { + return + } + return out.Close() +} + +func detachSign(w io.Writer, signer *Entity, message io.Reader, sigType packet.SignatureType, config *packet.Config) (err error) { + if signer.PrivateKey == nil { + return errors.InvalidArgumentError("signing key doesn't have a private key") + } + if signer.PrivateKey.Encrypted { + return errors.InvalidArgumentError("signing key is encrypted") + } + + sig := new(packet.Signature) + sig.SigType = sigType + sig.PubKeyAlgo = signer.PrivateKey.PubKeyAlgo + sig.Hash = config.Hash() + sig.CreationTime = config.Now() + sig.IssuerKeyId = &signer.PrivateKey.KeyId + + h, wrappedHash, err := hashForSignature(sig.Hash, sig.SigType) + if err != nil { + return + } + io.Copy(wrappedHash, message) + + err = sig.Sign(h, signer.PrivateKey, config) + if err != nil { + return + } + + return sig.Serialize(w) +} + +// FileHints contains metadata about encrypted files. This metadata is, itself, +// encrypted. +type FileHints struct { + // IsBinary can be set to hint that the contents are binary data. + IsBinary bool + // FileName hints at the name of the file that should be written. It's + // truncated to 255 bytes if longer. It may be empty to suggest that the + // file should not be written to disk. It may be equal to "_CONSOLE" to + // suggest the data should not be written to disk. + FileName string + // ModTime contains the modification time of the file, or the zero time if not applicable. + ModTime time.Time +} + +// SymmetricallyEncrypt acts like gpg -c: it encrypts a file with a passphrase. +// The resulting WriteCloser must be closed after the contents of the file have +// been written. +// If config is nil, sensible defaults will be used. +func SymmetricallyEncrypt(ciphertext io.Writer, passphrase []byte, hints *FileHints, config *packet.Config) (plaintext io.WriteCloser, err error) { + if hints == nil { + hints = &FileHints{} + } + + key, err := packet.SerializeSymmetricKeyEncrypted(ciphertext, passphrase, config) + if err != nil { + return + } + w, err := packet.SerializeSymmetricallyEncrypted(ciphertext, config.Cipher(), key, config) + if err != nil { + return + } + + literaldata := w + if algo := config.Compression(); algo != packet.CompressionNone { + var compConfig *packet.CompressionConfig + if config != nil { + compConfig = config.CompressionConfig + } + literaldata, err = packet.SerializeCompressed(w, algo, compConfig) + if err != nil { + return + } + } + + var epochSeconds uint32 + if !hints.ModTime.IsZero() { + epochSeconds = uint32(hints.ModTime.Unix()) + } + return packet.SerializeLiteral(literaldata, hints.IsBinary, hints.FileName, epochSeconds) +} + +// intersectPreferences mutates and returns a prefix of a that contains only +// the values in the intersection of a and b. The order of a is preserved. +func intersectPreferences(a []uint8, b []uint8) (intersection []uint8) { + var j int + for _, v := range a { + for _, v2 := range b { + if v == v2 { + a[j] = v + j++ + break + } + } + } + + return a[:j] +} + +func hashToHashId(h crypto.Hash) uint8 { + v, ok := s2k.HashToHashId(h) + if !ok { + panic("tried to convert unknown hash") + } + return v +} + +// Encrypt encrypts a message to a number of recipients and, optionally, signs +// it. hints contains optional information, that is also encrypted, that aids +// the recipients in processing the message. The resulting WriteCloser must +// be closed after the contents of the file have been written. +// If config is nil, sensible defaults will be used. +func Encrypt(ciphertext io.Writer, to []*Entity, signed *Entity, hints *FileHints, config *packet.Config) (plaintext io.WriteCloser, err error) { + var signer *packet.PrivateKey + if signed != nil { + signKey, ok := signed.signingKey(config.Now()) + if !ok { + return nil, errors.InvalidArgumentError("no valid signing keys") + } + signer = signKey.PrivateKey + if signer == nil { + return nil, errors.InvalidArgumentError("no private key in signing key") + } + if signer.Encrypted { + return nil, errors.InvalidArgumentError("signing key must be decrypted") + } + } + + // These are the possible ciphers that we'll use for the message. + candidateCiphers := []uint8{ + uint8(packet.CipherAES128), + uint8(packet.CipherAES256), + uint8(packet.CipherCAST5), + } + // These are the possible hash functions that we'll use for the signature. + candidateHashes := []uint8{ + hashToHashId(crypto.SHA256), + hashToHashId(crypto.SHA512), + hashToHashId(crypto.SHA1), + hashToHashId(crypto.RIPEMD160), + } + // In the event that a recipient doesn't specify any supported ciphers + // or hash functions, these are the ones that we assume that every + // implementation supports. + defaultCiphers := candidateCiphers[len(candidateCiphers)-1:] + defaultHashes := candidateHashes[len(candidateHashes)-1:] + + encryptKeys := make([]Key, len(to)) + for i := range to { + var ok bool + encryptKeys[i], ok = to[i].encryptionKey(config.Now()) + if !ok { + return nil, errors.InvalidArgumentError("cannot encrypt a message to key id " + strconv.FormatUint(to[i].PrimaryKey.KeyId, 16) + " because it has no encryption keys") + } + + sig := to[i].primaryIdentity().SelfSignature + + preferredSymmetric := sig.PreferredSymmetric + if len(preferredSymmetric) == 0 { + preferredSymmetric = defaultCiphers + } + preferredHashes := sig.PreferredHash + if len(preferredHashes) == 0 { + preferredHashes = defaultHashes + } + candidateCiphers = intersectPreferences(candidateCiphers, preferredSymmetric) + candidateHashes = intersectPreferences(candidateHashes, preferredHashes) + } + + if len(candidateCiphers) == 0 || len(candidateHashes) == 0 { + return nil, errors.InvalidArgumentError("cannot encrypt because recipient set shares no common algorithms") + } + + cipher := packet.CipherFunction(candidateCiphers[0]) + // If the cipher specified by config is a candidate, we'll use that. + configuredCipher := config.Cipher() + for _, c := range candidateCiphers { + cipherFunc := packet.CipherFunction(c) + if cipherFunc == configuredCipher { + cipher = cipherFunc + break + } + } + + var hash crypto.Hash + for _, hashId := range candidateHashes { + if h, ok := s2k.HashIdToHash(hashId); ok && h.Available() { + hash = h + break + } + } + + // If the hash specified by config is a candidate, we'll use that. + if configuredHash := config.Hash(); configuredHash.Available() { + for _, hashId := range candidateHashes { + if h, ok := s2k.HashIdToHash(hashId); ok && h == configuredHash { + hash = h + break + } + } + } + + if hash == 0 { + hashId := candidateHashes[0] + name, ok := s2k.HashIdToString(hashId) + if !ok { + name = "#" + strconv.Itoa(int(hashId)) + } + return nil, errors.InvalidArgumentError("cannot encrypt because no candidate hash functions are compiled in. (Wanted " + name + " in this case.)") + } + + symKey := make([]byte, cipher.KeySize()) + if _, err := io.ReadFull(config.Random(), symKey); err != nil { + return nil, err + } + + for _, key := range encryptKeys { + if err := packet.SerializeEncryptedKey(ciphertext, key.PublicKey, cipher, symKey, config); err != nil { + return nil, err + } + } + + encryptedData, err := packet.SerializeSymmetricallyEncrypted(ciphertext, cipher, symKey, config) + if err != nil { + return + } + + if signer != nil { + ops := &packet.OnePassSignature{ + SigType: packet.SigTypeBinary, + Hash: hash, + PubKeyAlgo: signer.PubKeyAlgo, + KeyId: signer.KeyId, + IsLast: true, + } + if err := ops.Serialize(encryptedData); err != nil { + return nil, err + } + } + + if hints == nil { + hints = &FileHints{} + } + + w := encryptedData + if signer != nil { + // If we need to write a signature packet after the literal + // data then we need to stop literalData from closing + // encryptedData. + w = noOpCloser{encryptedData} + + } + var epochSeconds uint32 + if !hints.ModTime.IsZero() { + epochSeconds = uint32(hints.ModTime.Unix()) + } + literalData, err := packet.SerializeLiteral(w, hints.IsBinary, hints.FileName, epochSeconds) + if err != nil { + return nil, err + } + + if signer != nil { + return signatureWriter{encryptedData, literalData, hash, hash.New(), signer, config}, nil + } + return literalData, nil +} + +// signatureWriter hashes the contents of a message while passing it along to +// literalData. When closed, it closes literalData, writes a signature packet +// to encryptedData and then also closes encryptedData. +type signatureWriter struct { + encryptedData io.WriteCloser + literalData io.WriteCloser + hashType crypto.Hash + h hash.Hash + signer *packet.PrivateKey + config *packet.Config +} + +func (s signatureWriter) Write(data []byte) (int, error) { + s.h.Write(data) + return s.literalData.Write(data) +} + +func (s signatureWriter) Close() error { + sig := &packet.Signature{ + SigType: packet.SigTypeBinary, + PubKeyAlgo: s.signer.PubKeyAlgo, + Hash: s.hashType, + CreationTime: s.config.Now(), + IssuerKeyId: &s.signer.KeyId, + } + + if err := sig.Sign(s.h, s.signer, s.config); err != nil { + return err + } + if err := s.literalData.Close(); err != nil { + return err + } + if err := sig.Serialize(s.encryptedData); err != nil { + return err + } + return s.encryptedData.Close() +} + +// noOpCloser is like an ioutil.NopCloser, but for an io.Writer. +// TODO: we have two of these in OpenPGP packages alone. This probably needs +// to be promoted somewhere more common. +type noOpCloser struct { + w io.Writer +} + +func (c noOpCloser) Write(data []byte) (n int, err error) { + return c.w.Write(data) +} + +func (c noOpCloser) Close() error { + return nil +}