glider-ssh/_examples/ssh-remoteforward/portforward.go

32 lines
730 B
Go
Raw Permalink Normal View History

Remote forwarding (#88) * context: fixed documentation to be more specific about ContextKeyConn being the key for a gossh.ServerConn Signed-off-by: Jeff Lindsay <progrium@gmail.com> * server: fixes handler setup, changed to interface based handlers, added global request handler map * tcpip: working remote forwarding Signed-off-by: Jeff Lindsay <progrium@gmail.com> * context: docs typo Signed-off-by: Jeff Lindsay <progrium@gmail.com> * session: always reply to unblock clients trying something Signed-off-by: Jeff Lindsay <progrium@gmail.com> * tcpip: stop listening when ssh clients disconnect Signed-off-by: Jeff Lindsay <progrium@gmail.com> * Remote forwarding (#87) * Update generateSigner key size to 2048 (#62) Fixes #58 * Add syntax highlighting to readme (#67) * small api updates (#69) These updates make it easier to implement and pass custom Session and Context implementations No compatibilty breaking, all tests pass * Move channelHandlers to avoid data race (#59) * Update tests to work with go 1.10+ (#73) Fixes #72 * Update shutdown to use a WaitGroup rather than sleeping (#74) * Fix race condition in TestServerClose (#75) In test server close, 3 things need to happen in order: - Client session start - Server.Close - Client session exit (With io.EOF) This fix ensures the client won't do anything until after the call to close which ensure's we'll get io.EOF rather than a different error. * Update circleci config to test multiple go versions * Update CircleCI config to test 1.9 and the latest The x/crypto/ssh library dropped support go < 1.9 as that's the first version to have the math/bits library. https://github.com/golang/crypto/commit/83c378c48d6ee2ca9c20551b599aa74cb7765785 * Wait for connections to finish when shutting down PR #74 introduced a WaitGroup for listeners, but it doesn't wait for open connections before closing the server. This patch waits until all conns are closed before returning from Shutdown. * Support port forwarding of literal IPv6 addresses (#85) * Support port forwarding of literal IPv6 addresses To disambiguate between colons as host:port separators and as IPv6 address separators, literal IPv6 addresses use square brackets around the address (https://en.wikipedia.org/wiki/IPv6_address#Literal_IPv6_addresses_in_network_resource_identifiers). So host ::1, port 22 is written as [::1]:22, and therefore a simple concatenation of host, colon, and port doesn't work. Fortunately net.JoinHostPort already implements this functionality, so with a bit of type gymnastics we can generate dest in an IPv6-safe way. * Support port forwarding of literal IPv6 addresses To disambiguate between colons as host:port separators and as IPv6 address separators, literal IPv6 addresses use square brackets around the address (https://en.wikipedia.org/wiki/IPv6_address#Literal_IPv6_addresses_in_network_resource_identifiers). So host ::1, port 22 is written as [::1]:22, and therefore a simple concatenation of host, colon, and port doesn't work. Fortunately net.JoinHostPort already implements this functionality, so with a bit of type gymnastics we can generate dest in an IPv6-safe way. * Reverse port forwarding callback added * garbage removed
2018-11-13 16:04:02 +00:00
package main
import (
"io"
"log"
"github.com/gliderlabs/ssh"
)
func main() {
log.Println("starting ssh server on port 2222...")
server := ssh.Server{
LocalPortForwardingCallback: ssh.LocalPortForwardingCallback(func(ctx ssh.Context, dhost string, dport uint32) bool {
log.Println("Accepted forward", dhost, dport)
return true
}),
Addr: ":2222",
Handler: ssh.Handler(func(s ssh.Session) {
io.WriteString(s, "Remote forwarding available...\n")
select {}
}),
ReversePortForwardingCallback: ssh.ReversePortForwardingCallback(func(ctx ssh.Context, host string, port uint32) bool {
log.Println("attempt to bind", host, port, "granted")
return true
}),
}
log.Fatal(server.ListenAndServe())
}