open-nomad/vendor/golang.org/x/crypto/ssh/connection.go
Seth Hoenig 435c0d9fc8 deps: Switch to Go modules for dependency management
This PR switches the Nomad repository from using govendor to Go modules
for managing dependencies. Aspects of the Nomad workflow remain pretty
much the same. The usual Makefile targets should continue to work as
they always did. The API submodule simply defers to the parent Nomad
version on the repository, keeping the semantics of API versioning that
currently exists.
2020-06-02 14:30:36 -05:00

144 lines
3.3 KiB
Go

// Copyright 2013 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 ssh
import (
"fmt"
"net"
)
// OpenChannelError is returned if the other side rejects an
// OpenChannel request.
type OpenChannelError struct {
Reason RejectionReason
Message string
}
func (e *OpenChannelError) Error() string {
return fmt.Sprintf("ssh: rejected: %s (%s)", e.Reason, e.Message)
}
// ConnMetadata holds metadata for the connection.
type ConnMetadata interface {
// User returns the user ID for this connection.
User() string
// SessionID returns the session hash, also denoted by H.
SessionID() []byte
// ClientVersion returns the client's version string as hashed
// into the session ID.
ClientVersion() []byte
// ServerVersion returns the server's version string as hashed
// into the session ID.
ServerVersion() []byte
// RemoteAddr returns the remote address for this connection.
RemoteAddr() net.Addr
// LocalAddr returns the local address for this connection.
LocalAddr() net.Addr
}
// Conn represents an SSH connection for both server and client roles.
// Conn is the basis for implementing an application layer, such
// as ClientConn, which implements the traditional shell access for
// clients.
type Conn interface {
ConnMetadata
// SendRequest sends a global request, and returns the
// reply. If wantReply is true, it returns the response status
// and payload. See also RFC4254, section 4.
SendRequest(name string, wantReply bool, payload []byte) (bool, []byte, error)
// OpenChannel tries to open an channel. If the request is
// rejected, it returns *OpenChannelError. On success it returns
// the SSH Channel and a Go channel for incoming, out-of-band
// requests. The Go channel must be serviced, or the
// connection will hang.
OpenChannel(name string, data []byte) (Channel, <-chan *Request, error)
// Close closes the underlying network connection
Close() error
// Wait blocks until the connection has shut down, and returns the
// error causing the shutdown.
Wait() error
// TODO(hanwen): consider exposing:
// RequestKeyChange
// Disconnect
}
// DiscardRequests consumes and rejects all requests from the
// passed-in channel.
func DiscardRequests(in <-chan *Request) {
for req := range in {
if req.WantReply {
req.Reply(false, nil)
}
}
}
// A connection represents an incoming connection.
type connection struct {
transport *handshakeTransport
sshConn
// The connection protocol.
*mux
}
func (c *connection) Close() error {
return c.sshConn.conn.Close()
}
// sshconn provides net.Conn metadata, but disallows direct reads and
// writes.
type sshConn struct {
conn net.Conn
user string
sessionID []byte
clientVersion []byte
serverVersion []byte
}
func dup(src []byte) []byte {
dst := make([]byte, len(src))
copy(dst, src)
return dst
}
func (c *sshConn) User() string {
return c.user
}
func (c *sshConn) RemoteAddr() net.Addr {
return c.conn.RemoteAddr()
}
func (c *sshConn) Close() error {
return c.conn.Close()
}
func (c *sshConn) LocalAddr() net.Addr {
return c.conn.LocalAddr()
}
func (c *sshConn) SessionID() []byte {
return dup(c.sessionID)
}
func (c *sshConn) ClientVersion() []byte {
return dup(c.clientVersion)
}
func (c *sshConn) ServerVersion() []byte {
return dup(c.serverVersion)
}