knownhosts

Documentation

Overview

Package knownhosts implements a parser for the OpenSSH known_hosts host key database, and provides utility functions for writing OpenSSH compliant known_hosts files.

Index

• func HashHostname(hostname string) string
• func Line(addresses []string, key ssh.PublicKey) string
• func New(files ...string) (ssh.HostKeyCallback, error)
• func Normalize(address string) string
• type KeyError
  • func (u *KeyError) Error() string
• type KnownKey
  • func (k *KnownKey) String() string
• type RevokedError
  • func (r *RevokedError) Error() string

Functions

func HashHostname

func HashHostname(hostname string) string

HashHostname hashes the given hostname. The hostname is not normalized before hashing.

func Line

func Line(addresses []string, key ssh.PublicKey) string

Line returns a line to add append to the known_hosts files.

func New

func New(files ...string) (ssh.HostKeyCallback, error)

New creates a host key callback from the given OpenSSH host key files. The returned callback is for use in ssh.ClientConfig.HostKeyCallback. By preference, the key check operates on the hostname if available, i.e. if a server changes its IP address, the host key check will still succeed, even though a record of the new IP address is not available.

func Normalize

func Normalize(address string) string

Normalize normalizes an address into the form used in known_hosts

Types

type KeyError

type KeyError struct {
	// Want holds the accepted host keys. For each key algorithm,
	// there can be one hostkey.  If Want is empty, the host is
	// unknown. If Want is non-empty, there was a mismatch, which
	// can signify a MITM attack.
	Want []KnownKey
}

KeyError is returned if we did not find the key in the host key database, or there was a mismatch. Typically, in batch applications, this should be interpreted as failure. Interactive applications can offer an interactive prompt to the user.

func (*KeyError) Error

func (u *KeyError) Error() string

type KnownKey

type KnownKey struct {
	Key      ssh.PublicKey
	Filename string
	Line     int
}

KnownKey represents a key declared in a known_hosts file.

func (*KnownKey) String

func (k *KnownKey) String() string

type RevokedError

type RevokedError struct {
	Revoked KnownKey
}

RevokedError is returned if we found a key that was revoked.

func (*RevokedError) Error

func (r *RevokedError) Error() string