Documentation
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Index ¶
- Constants
- func GenerateBundle() (BundlePub, BundlePriv, error)
- func GenerateExchange() (ExchangePub, ExchangePriv, error)
- func GenerateIdentity() (IdentityPub, IdentityPriv, error)
- type BackwardExchangeParams
- type BundlePriv
- type BundlePub
- type DoubleRatchet
- type ExchangePriv
- type ExchangePub
- type ForwardExchangeParams
- type IdentityPriv
- type IdentityPub
- type MessageKey
- type SharedSecret
- type Signature
Constants ¶
const ExchangePubSize = curve25519.PointSize
const ExchangeSecretSize = curve25519.PointSize
const IdentityPubSize = ed25519.PublicKeySize
const MessageKeySize = 32
MessageKeySize is the number of bytes in a message key
SharedSecretSize is the number of bytes in a shared secret
Variables ¶
This section is empty.
Functions ¶
func GenerateBundle ¶
func GenerateBundle() (BundlePub, BundlePriv, error)
GenerateBundle generates a new bundle of exchange keys, possibly failing
func GenerateExchange ¶
func GenerateExchange() (ExchangePub, ExchangePriv, error)
GenerateExchange creates a new exchange key-pair
This will use a secure source of randomness.
An error may be returned if generation fails.
func GenerateIdentity ¶
func GenerateIdentity() (IdentityPub, IdentityPriv, error)
GenerateIdentity creates a new identity key-pair.
This generates a new key, using a secure source of randomness.
An error may be returned if generation fails.
Types ¶
type BackwardExchangeParams ¶
type BackwardExchangeParams struct {
// The public identity of the initiator
Them IdentityPub
// The Ephemeral key used by the initiator
Ephemeral ExchangePub
// The private Identity of the recipient
Identity IdentityPriv
// The private Prekey of the recipient
Prekey ExchangePriv
// The private OneTime key of the recipient
OneTime ExchangePriv
}
BackwardExchangeParams contains the parameters for an exchange from a recipient
type BundlePriv ¶
type BundlePriv []ExchangePriv
BundlePriv is a collection of the private counterparts to single-use exchange keys
type BundlePub ¶
type BundlePub []byte
BundlePub is a collection of single-use exchange keys
func BundleFromBytes ¶
BundleFromBytes converts a slice of bytes into a public bundle.
This will fail if the length of the data doesn't match an expected length for a bundle.
func (BundlePub) Get ¶
func (bundle BundlePub) Get(index int) ExchangePub
Get returns the exchange key at a given index.
This will panic if the index is < 0 or >= bundle.Len().
type DoubleRatchet ¶
type DoubleRatchet struct {
// contains filtered or unexported fields
}
DoubleRatchet holds the state used for the Diffie Hellman double ratchet.
This will be setup based on the exchange to derive a secret, and then updated as messages arrive.
func DoubleRatchetFromInitiator ¶
func DoubleRatchetFromInitiator(secret SharedSecret, receivingPub ExchangePub) (ratchet DoubleRatchet, err error)
DoubleRatchetFromInitiator creates a double ratchet, with information by the initiator of an exchange.
The parameters passed by this function should be known to the initiator of an X3DH exchange.
The receivingPub should be the signed prekey.
func DoubleRatchetFromReceiver ¶
func DoubleRatchetFromReceiver(secret SharedSecret, pub ExchangePub, priv ExchangePriv) DoubleRatchet
DoubleRatchetFromReceiver creates a double ratchet, with information from the receiver of an exchange.
We use the shared secret we've derived from an exchange, as well as our signed prekey.
func (*DoubleRatchet) Decrypt ¶
func (ratchet *DoubleRatchet) Decrypt(ciphertext, additional []byte) ([]byte, error)
Decrypt uses the current state of the ratchet to decrypt a piece of data.
The ciphertext will contain the necessary headers.
This will also advance the state of the ratchet accordingly.
type ExchangePriv ¶
type ExchangePriv []byte
ExchangePriv is the private component of an exchange key
type ExchangePub ¶
type ExchangePub []byte
ExchangePub is the public component of an exchange key
func ExchangePubFromBytes ¶
func ExchangePubFromBytes(pubBytes []byte) (ExchangePub, error)
ExchangePubFromBytes creates a public exchange key from bytes
This will return an error if the number of bytes is incorrect.
type ForwardExchangeParams ¶
type ForwardExchangeParams struct {
// The private identity key for the initiator
Me IdentityPriv
// The private part of an Ephemeral exchange key
Ephemeral ExchangePriv
// The public Identity key for the recipient
Identity IdentityPub
// The signed Prekey for the recipient
Prekey ExchangePub
// The OneTime key for the recipient
OneTime ExchangePub
}
ForwardExchangeParams is the information to do an exchange, from a person initiating the exchange
type IdentityPriv ¶
type IdentityPriv ed25519.PrivateKey
IdentityPriv is the private component of an identity key
This can be used to generate signatures for an identity.
func (IdentityPriv) Sign ¶
func (priv IdentityPriv) Sign(data []byte) Signature
Sign uses an identity to generate signature for some data
Forging this signature should be impossible without having acess to the private key. Anyone with the public part of an identity key can verify the signature.
func (IdentityPriv) SignBundle ¶
func (priv IdentityPriv) SignBundle(bundle BundlePub) Signature
SignBundle uses an identity key to sign a bundle of exchange keys
type IdentityPub ¶
IdentityPub is the public component of an identity key
This can be used to verify signatures from an identity.
func IdentityPubFromBase64 ¶
func IdentityPubFromBase64(data string) (IdentityPub, error)
IdentityPubFromBase64 attempts to convert URL-safe Base64 into a public identity key
This will return an error if decoding fails, or if the number of bytes doesn't match the size of a public key.
func IdentityPubFromString ¶
func IdentityPubFromString(s string) (IdentityPub, error)
IdentityPubFromString attempts to parse an identity from a string, potentially failing
func (IdentityPub) String ¶
func (pub IdentityPub) String() string
String returns the string representation of an identity
func (IdentityPub) Verify ¶
func (pub IdentityPub) Verify(data []byte, sig Signature) bool
Verify uses the public part of an identity to verify a signature on some data
func (IdentityPub) VerifyBundle ¶
func (pub IdentityPub) VerifyBundle(bundle BundlePub, sig Signature) bool
VerifyBundle verifies a signature generated over a bundle of exchange keys
type MessageKey ¶
type MessageKey []byte
messageKey represents a key used for encrypting messages
type SharedSecret ¶
type SharedSecret []byte
SharedSecret is derived between two parties, exchanging only public information
func BackwardExchange ¶
func BackwardExchange(params *BackwardExchangeParams) (SharedSecret, error)
BackwardExchange derives a shared secret, using the initiators public information
This is the corollary to ForwardExchange, allow the recipient to derive a shared secret with an initiator. This is done with the recipient's private information, and the initiator's public information.
func ForwardExchange ¶
func ForwardExchange(params *ForwardExchangeParams) (SharedSecret, error)
ForwardExchange performs an exchange with the parameters, deriving a shared secret.
This exchange is used by an initiator, with their private information, to derive a shared secret with a recipient, using their public information.
Source Files