Add vendor files for spf13/viper

1 files changed, 376 insertions, 0 deletions

diff --git a/vendor/golang.org/x/crypto/openpgp/clearsign/clearsign.go b/vendor/golang.org/x/crypto/openpgp/clearsign/clearsign.go
new file mode 100644
index 00000000..def4caba
--- /dev/null
+++ b/vendor/golang.org/x/crypto/openpgp/clearsign/clearsign.go
@@ -0,0 +1,376 @@
+// 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.
+
+// Package clearsign generates and processes OpenPGP, clear-signed data. See
+// RFC 4880, section 7.
+//
+// Clearsigned messages are cryptographically signed, but the contents of the
+// message are kept in plaintext so that it can be read without special tools.
+package clearsign // import "golang.org/x/crypto/openpgp/clearsign"
+
+import (
+	"bufio"
+	"bytes"
+	"crypto"
+	"hash"
+	"io"
+	"net/textproto"
+	"strconv"
+
+	"golang.org/x/crypto/openpgp/armor"
+	"golang.org/x/crypto/openpgp/errors"
+	"golang.org/x/crypto/openpgp/packet"
+)
+
+// A Block represents a clearsigned message. A signature on a Block can
+// be checked by passing Bytes into openpgp.CheckDetachedSignature.
+type Block struct {
+	Headers          textproto.MIMEHeader // Optional message headers
+	Plaintext        []byte               // The original message text
+	Bytes            []byte               // The signed message
+	ArmoredSignature *armor.Block         // The signature block
+}
+
+// start is the marker which denotes the beginning of a clearsigned message.
+var start = []byte("\n-----BEGIN PGP SIGNED MESSAGE-----")
+
+// dashEscape is prefixed to any lines that begin with a hyphen so that they
+// can't be confused with endText.
+var dashEscape = []byte("- ")
+
+// endText is a marker which denotes the end of the message and the start of
+// an armored signature.
+var endText = []byte("-----BEGIN PGP SIGNATURE-----")
+
+// end is a marker which denotes the end of the armored signature.
+var end = []byte("\n-----END PGP SIGNATURE-----")
+
+var crlf = []byte("\r\n")
+var lf = byte('\n')
+
+// getLine returns the first \r\n or \n delineated line from the given byte
+// array. The line does not include the \r\n or \n. The remainder of the byte
+// array (also not including the new line bytes) is also returned and this will
+// always be smaller than the original argument.
+func getLine(data []byte) (line, rest []byte) {
+	i := bytes.Index(data, []byte{'\n'})
+	var j int
+	if i < 0 {
+		i = len(data)
+		j = i
+	} else {
+		j = i + 1
+		if i > 0 && data[i-1] == '\r' {
+			i--
+		}
+	}
+	return data[0:i], data[j:]
+}
+
+// Decode finds the first clearsigned message in data and returns it, as well
+// as the suffix of data which remains after the message.
+func Decode(data []byte) (b *Block, rest []byte) {
+	// start begins with a newline. However, at the very beginning of
+	// the byte array, we'll accept the start string without it.
+	rest = data
+	if bytes.HasPrefix(data, start[1:]) {
+		rest = rest[len(start)-1:]
+	} else if i := bytes.Index(data, start); i >= 0 {
+		rest = rest[i+len(start):]
+	} else {
+		return nil, data
+	}
+
+	// Consume the start line.
+	_, rest = getLine(rest)
+
+	var line []byte
+	b = &Block{
+		Headers: make(textproto.MIMEHeader),
+	}
+
+	// Next come a series of header lines.
+	for {
+		// This loop terminates because getLine's second result is
+		// always smaller than its argument.
+		if len(rest) == 0 {
+			return nil, data
+		}
+		// An empty line marks the end of the headers.
+		if line, rest = getLine(rest); len(line) == 0 {
+			break
+		}
+
+		i := bytes.Index(line, []byte{':'})
+		if i == -1 {
+			return nil, data
+		}
+
+		key, val := line[0:i], line[i+1:]
+		key = bytes.TrimSpace(key)
+		val = bytes.TrimSpace(val)
+		b.Headers.Add(string(key), string(val))
+	}
+
+	firstLine := true
+	for {
+		start := rest
+
+		line, rest = getLine(rest)
+		if len(line) == 0 && len(rest) == 0 {
+			// No armored data was found, so this isn't a complete message.
+			return nil, data
+		}
+		if bytes.Equal(line, endText) {
+			// Back up to the start of the line because armor expects to see the
+			// header line.
+			rest = start
+			break
+		}
+
+		// The final CRLF isn't included in the hash so we don't write it until
+		// we've seen the next line.
+		if firstLine {
+			firstLine = false
+		} else {
+			b.Bytes = append(b.Bytes, crlf...)
+		}
+
+		if bytes.HasPrefix(line, dashEscape) {
+			line = line[2:]
+		}
+		line = bytes.TrimRight(line, " \t")
+		b.Bytes = append(b.Bytes, line...)
+
+		b.Plaintext = append(b.Plaintext, line...)
+		b.Plaintext = append(b.Plaintext, lf)
+	}
+
+	// We want to find the extent of the armored data (including any newlines at
+	// the end).
+	i := bytes.Index(rest, end)
+	if i == -1 {
+		return nil, data
+	}
+	i += len(end)
+	for i < len(rest) && (rest[i] == '\r' || rest[i] == '\n') {
+		i++
+	}
+	armored := rest[:i]
+	rest = rest[i:]
+
+	var err error
+	b.ArmoredSignature, err = armor.Decode(bytes.NewBuffer(armored))
+	if err != nil {
+		return nil, data
+	}
+
+	return b, rest
+}
+
+// A dashEscaper is an io.WriteCloser which processes the body of a clear-signed
+// message. The clear-signed message is written to buffered and a hash, suitable
+// for signing, is maintained in h.
+//
+// When closed, an armored signature is created and written to complete the
+// message.
+type dashEscaper struct {
+	buffered *bufio.Writer
+	h        hash.Hash
+	hashType crypto.Hash
+
+	atBeginningOfLine bool
+	isFirstLine       bool
+
+	whitespace []byte
+	byteBuf    []byte // a one byte buffer to save allocations
+
+	privateKey *packet.PrivateKey
+	config     *packet.Config
+}
+
+func (d *dashEscaper) Write(data []byte) (n int, err error) {
+	for _, b := range data {
+		d.byteBuf[0] = b
+
+		if d.atBeginningOfLine {
+			// The final CRLF isn't included in the hash so we have to wait
+			// until this point (the start of the next line) before writing it.
+			if !d.isFirstLine {
+				d.h.Write(crlf)
+			}
+			d.isFirstLine = false
+		}
+
+		// Any whitespace at the end of the line has to be removed so we
+		// buffer it until we find out whether there's more on this line.
+		if b == ' ' || b == '\t' || b == '\r' {
+			d.whitespace = append(d.whitespace, b)
+			d.atBeginningOfLine = false
+			continue
+		}
+
+		if d.atBeginningOfLine {
+			// At the beginning of a line, hyphens have to be escaped.
+			if b == '-' {
+				// The signature isn't calculated over the dash-escaped text so
+				// the escape is only written to buffered.
+				if _, err = d.buffered.Write(dashEscape); err != nil {
+					return
+				}
+				d.h.Write(d.byteBuf)
+				d.atBeginningOfLine = false
+			} else if b == '\n' {
+				// Nothing to do because we delay writing CRLF to the hash.
+			} else {
+				d.h.Write(d.byteBuf)
+				d.atBeginningOfLine = false
+			}
+			if err = d.buffered.WriteByte(b); err != nil {
+				return
+			}
+		} else {
+			if b == '\n' {
+				// We got a raw \n. Drop any trailing whitespace and write a
+				// CRLF.
+				d.whitespace = d.whitespace[:0]
+				// We delay writing CRLF to the hash until the start of the
+				// next line.
+				if err = d.buffered.WriteByte(b); err != nil {
+					return
+				}
+				d.atBeginningOfLine = true
+			} else {
+				// Any buffered whitespace wasn't at the end of the line so
+				// we need to write it out.
+				if len(d.whitespace) > 0 {
+					d.h.Write(d.whitespace)
+					if _, err = d.buffered.Write(d.whitespace); err != nil {
+						return
+					}
+					d.whitespace = d.whitespace[:0]
+				}
+				d.h.Write(d.byteBuf)
+				if err = d.buffered.WriteByte(b); err != nil {
+					return
+				}
+			}
+		}
+	}
+
+	n = len(data)
+	return
+}
+
+func (d *dashEscaper) Close() (err error) {
+	if !d.atBeginningOfLine {
+		if err = d.buffered.WriteByte(lf); err != nil {
+			return
+		}
+	}
+	sig := new(packet.Signature)
+	sig.SigType = packet.SigTypeText
+	sig.PubKeyAlgo = d.privateKey.PubKeyAlgo
+	sig.Hash = d.hashType
+	sig.CreationTime = d.config.Now()
+	sig.IssuerKeyId = &d.privateKey.KeyId
+
+	if err = sig.Sign(d.h, d.privateKey, d.config); err != nil {
+		return
+	}
+
+	out, err := armor.Encode(d.buffered, "PGP SIGNATURE", nil)
+	if err != nil {
+		return
+	}
+
+	if err = sig.Serialize(out); err != nil {
+		return
+	}
+	if err = out.Close(); err != nil {
+		return
+	}
+	if err = d.buffered.Flush(); err != nil {
+		return
+	}
+	return
+}
+
+// Encode returns a WriteCloser which will clear-sign a message with privateKey
+// and write it to w. If config is nil, sensible defaults are used.
+func Encode(w io.Writer, privateKey *packet.PrivateKey, config *packet.Config) (plaintext io.WriteCloser, err error) {
+	if privateKey.Encrypted {
+		return nil, errors.InvalidArgumentError("signing key is encrypted")
+	}
+
+	hashType := config.Hash()
+	name := nameOfHash(hashType)
+	if len(name) == 0 {
+		return nil, errors.UnsupportedError("unknown hash type: " + strconv.Itoa(int(hashType)))
+	}
+
+	if !hashType.Available() {
+		return nil, errors.UnsupportedError("unsupported hash type: " + strconv.Itoa(int(hashType)))
+	}
+	h := hashType.New()
+
+	buffered := bufio.NewWriter(w)
+	// start has a \n at the beginning that we don't want here.
+	if _, err = buffered.Write(start[1:]); err != nil {
+		return
+	}
+	if err = buffered.WriteByte(lf); err != nil {
+		return
+	}
+	if _, err = buffered.WriteString("Hash: "); err != nil {
+		return
+	}
+	if _, err = buffered.WriteString(name); err != nil {
+		return
+	}
+	if err = buffered.WriteByte(lf); err != nil {
+		return
+	}
+	if err = buffered.WriteByte(lf); err != nil {
+		return
+	}
+
+	plaintext = &dashEscaper{
+		buffered: buffered,
+		h:        h,
+		hashType: hashType,
+
+		atBeginningOfLine: true,
+		isFirstLine:       true,
+
+		byteBuf: make([]byte, 1),
+
+		privateKey: privateKey,
+		config:     config,
+	}
+
+	return
+}
+
+// nameOfHash returns the OpenPGP name for the given hash, or the empty string
+// if the name isn't known. See RFC 4880, section 9.4.
+func nameOfHash(h crypto.Hash) string {
+	switch h {
+	case crypto.MD5:
+		return "MD5"
+	case crypto.SHA1:
+		return "SHA1"
+	case crypto.RIPEMD160:
+		return "RIPEMD160"
+	case crypto.SHA224:
+		return "SHA224"
+	case crypto.SHA256:
+		return "SHA256"
+	case crypto.SHA384:
+		return "SHA384"
+	case crypto.SHA512:
+		return "SHA512"
+	}
+	return ""
+}