clearsign

Documentation

Overview

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.

Index

• func Encode(w io.Writer, privateKey *packet.PrivateKey, config *packet.Config) (plaintext io.WriteCloser, err error)
• func EncodeMulti(w io.Writer, privateKeys []*packet.PrivateKey, config *packet.Config) (plaintext io.WriteCloser, err error)
• type Block
  • func Decode(data []byte) (b *Block, rest []byte)
  • func (b *Block) VerifySignature(keyring openpgp.KeyRing, config *packet.Config) (signer *openpgp.Entity, err error)

Functions

func Encode

func Encode(w io.Writer, privateKey *packet.PrivateKey, config *packet.Config) (plaintext io.WriteCloser, err error)

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 EncodeMulti

func EncodeMulti(w io.Writer, privateKeys []*packet.PrivateKey, config *packet.Config) (plaintext io.WriteCloser, err error)

EncodeMulti returns a WriteCloser which will clear-sign a message with all the private keys indicated and write it to w. If config is nil, sensible defaults are used.

Types

type Block

type Block struct {
	Headers          textproto.MIMEHeader // Optional unverified Hash headers
	Plaintext        []byte               // The original message text
	Bytes            []byte               // The signed message
	ArmoredSignature *armor.Block         // The signature block
}

A Block represents a clearsigned message. A signature on a Block can be checked by calling Block.VerifySignature.

func Decode

func Decode(data []byte) (b *Block, rest []byte)

Decode finds the first clearsigned message in data and returns it, as well as the suffix of data which remains after the message. Any prefix data is discarded.

If no message is found, or if the message is invalid, Decode returns nil and the whole data slice. The only allowed header type is Hash, and it is not verified against the signature hash.

func (*Block) VerifySignature

func (b *Block) VerifySignature(keyring openpgp.KeyRing, config *packet.Config) (signer *openpgp.Entity, err error)

VerifySignature checks a clearsigned message signature, and checks that the hash algorithm in the header matches the hash algorithm in the signature.